JP5510092B2 - Method for producing modified cellulose fiber dispersion and method for producing cellulose composite material - Google Patents

Description

  The present invention relates to a method for producing a modified cellulose fiber dispersion and a modified cellulose fiber sheet, and a method for producing a cellulose composite material using the produced modified cellulose fiber dispersion or modified cellulose fiber sheet. By controlling the modification group of the fiber and further the modification rate, the productivity was improved and the required properties such as high heat resistance, high transparency, non-colorability, low linear expansion coefficient, and high elastic modulus were improved. A cellulose composite material is provided.

  In general, glass plates are widely used for display substrates such as liquid crystal and organic EL. However, glass plates have a high specific gravity and are difficult to reduce in weight, and also have drawbacks such as being easily broken, not being bent, and requiring a certain thickness. Is being considered. Specifically, a display substrate using polycarbonate or polyethylene terephthalate is used.

  However, these conventional plastic materials for glass replacement have a larger coefficient of linear expansion than glass plates, so in the process of depositing a device layer such as a thin film transistor on a substrate at a high temperature, warping, cracking of the deposited film, disconnection of the semiconductor Such problems are likely to occur and practical use is difficult.

  That is, for these applications, a plastic material having high transparency, high heat resistance, low water absorption, low linear expansion coefficient, and high strength is required.

  In recent years, composite materials using fine cellulose fibers such as bacterial cellulose have been actively studied. Since cellulose has an extended chain crystal, it is known to exhibit a low linear expansion coefficient, a high elastic modulus, and a high strength. Finer and finer cellulose nanofibers with a fiber diameter in the range of several nanometers to 200 nm can be obtained by miniaturization, and high transparency and low linear expansion can be obtained by filling the gaps between the fibers with a matrix material. It has been reported that composite materials having a modulus can be obtained.

  For example, Patent Document 1 describes a composite material of a nonwoven fabric made of cellulose fine fibers and a photocurable resin. By chemically modifying the cellulose fine fibers, water absorption is reduced and transparency is improved. Obtaining improved composite materials. Patent Document 1 discloses aliphatic substituents as modified substituents for cellulose, and particularly acetyl groups and methacryloyl groups are preferred.

  Patent Document 2 discloses a nonwoven fabric composed of modified fibers into which a compound having an aromatic ring structure is introduced as a compound for controlling optical anisotropy.

  Non-Patent Document 1 discloses benzoylated bacterial cellulose exhibiting thermotropic liquid crystal characteristics.

JP 2007-51266 A JP 2008-274461 A

Carbohydrr Polym, Vol. 74, no. 4, P875-879 (2008)

The method for producing a cellulose fine fiber nonwoven fabric (cellulose sheet) specifically disclosed in Patent Document 1 described above is a mechanically defibrated cellulose fine fiber aqueous suspension filtered through a glass filter and dehydrated. This is a method of forming a film.
However, when the present inventors manufactured a cellulose composite material according to the method disclosed in Patent Document 1, it was used for filtration for dehydration of an aqueous suspension of cellulose fine fibers when manufacturing a cellulose sheet. It was found that such a time was long and practical productivity could not be obtained.

The nonwoven fabric (cellulose sheet) specifically disclosed in Patent Document 2 is a hemp (for example, abaca used in Comparative Examples 3 to 5 described later) derived pulp, bagasse derived pulp, kenaf derived pulp as a cellulose raw material, Bamboo-derived pulp is used.
However, when the present inventors manufactured a cellulose sheet according to the method disclosed in Patent Document 2, it was found that hemp-derived pulp, bagasse-derived pulp, kenaf-derived pulp, and bamboo-derived pulp are difficult to be refined. . Therefore, even if the cellulose sheet obtained from the cellulose raw material disclosed in Patent Document 2 and the polymer material are combined, a cellulose composite material having a low linear expansion coefficient, a high elastic modulus, and a high strength is not obtained.

  The benzoylated bacterial cellulose obtained by the method of Non-Patent Document 1 is amorphous because it has a glass transition temperature. What is a composite material having a low linear expansion coefficient even if it is combined with a polymer material? It turned out not to be.

  In view of the above situation, an object of the present invention is to provide a cellulose composite material that realizes high productivity in the production of a cellulose sheet and has excellent transparency, non-coloring property, low linear expansion coefficient, and high elastic modulus. And

  As a result of intensive studies to solve the above problems, the present inventors have defibrated modified cellulose modified with an aromatic ring-containing substituent to an average fiber diameter of 100 nm or less to obtain a modified cellulose fiber dispersion. The present inventors have found that the above filtration time when producing a cellulose sheet is remarkably shortened. In addition, woody materials are used as cellulose raw materials, and together with the modified substituents and modification rate of modified cellulose fibers, the fiber diameter and crystal structure are controlled to provide excellent transparency and non-coloring properties. It has been found that a cellulose composite material having a low linear expansion coefficient and a high elastic modulus can be obtained.

  The present invention has been achieved on the basis of such knowledge, and the gist thereof is as follows.

[1] A method for producing a dispersion of modified cellulose fibers having an average fiber diameter of 100 nm or less and having a cellulose I-type crystal structure modified with an aromatic ring-containing substituent,
(1) A process of obtaining modified cellulose by modifying cellulose before defibration obtained from wood with an aromatic ring-containing substituent
(2) A method for producing a modified cellulose fiber dispersion, comprising sequentially performing a step of defibrating the modified cellulose obtained in (1) to an average fiber diameter of 100 nm or less to obtain a modified cellulose fiber dispersion.

[2] The method for producing a modified cellulose fiber dispersion according to [1], wherein the aromatic ring-containing substituent is an aromatic ring-containing ester group.

[3] The method for producing a modified cellulose fiber dispersion according to [1] or [2], wherein the modification ratio of cellulose to all hydroxyl groups is 9 mol% or less.

[4] A method for producing a modified cellulose fiber sheet, comprising a step of papermaking the modified cellulose fiber dispersion obtained by the method according to any one of [1] to [3].
(Hereinafter, cellulose fiber sheets may be referred to as “cellulose sheets”.)

[5] Cellulose fibers contained in the modified cellulose fiber dispersion obtained by the method according to any one of [1] to [3], or modified cellulose fiber sheet obtained by the method according to [4], and other than cellulose The manufacturing method of a cellulose composite material which has the process of combining with the polymer | macromolecule.

[6] A modified cellulose fiber dispersion obtained by the method according to any one of [1] to [3].

[7] A modified cellulose fiber sheet obtained by the method according to [4].

[8] A cellulose composite material obtained by the method according to [5].

  According to the present invention, using woody cellulose raw material, by controlling the modification substituent of the modified cellulose fiber, further the modification rate, the fiber diameter and the crystal structure, to achieve high productivity in the production of the cellulose sheet, When a composite material is used, excellent transparency, non-colorability, a low linear expansion coefficient, and a high elastic modulus can be realized. Furthermore, it can be expected that the affinity between the cellulose fiber and the polymer is improved, and the transparency and strength are further enhanced.

  Embodiments of the present invention will be specifically described below, but the present invention is not limited to the following embodiments, and various modifications can be made within the scope of the gist of the present invention.

[1] Method for Producing Modified Cellulose Fiber Dispersion The method for producing a modified cellulose fiber dispersion of the present invention is a modification having an average fiber diameter of 100 nm or less and having a cellulose type I crystal structure modified with an aromatic ring-containing substituent. A method for producing a dispersion of cellulose fibers, comprising:
(1) A step of modifying a cellulose before defibration obtained from wood with an aromatic ring-containing substituent to obtain a modified cellulose (hereinafter, this step may be referred to as a “modification step”).
(2) A step of defibrating the modified cellulose obtained in (1) to an average fiber diameter of 100 nm or less to obtain a modified cellulose fiber dispersion (hereinafter, this step may be referred to as “defibration step”).
Are performed in order.

[Cellulose before defibration]
The cellulose before defibration obtained from the wood in the present invention is produced by removing impurities from a woody cellulose-containing material as shown below through a general purification treatment.

<Cellulose-containing material>
Examples of the cellulose-containing material include woods such as conifers and hardwoods. These natural celluloses are preferable because they have high crystallinity and can realize a low linear expansion coefficient and a high elastic modulus. Furthermore, wood of conifers and hardwoods with fine fiber diameters can be obtained, and it is the largest amount of biological resources on the earth, and it is a sustainable resource that produces about 70 billion tons per year. Therefore, it contributes greatly to the reduction of carbon dioxide that affects global warming, which is advantageous from an economic point of view.

<Purification method of cellulose-containing material>
The cellulose before defibration used in the present invention is obtained by purifying the above cellulose-containing material by a usual method. Examples of the purification treatment include a method of defatting with benzene and ethanol or sodium carbonate, then subjecting to delignification treatment by the Wise method, and further subjecting to dehemicellulose treatment in an alkali. Or the chemical pulping method used with the general paper pulp can also be applied. In this case, for example, according to a method for producing kraft pulp, sulphide pulp, or alkali pulp, a method in which a cellulose-containing material is heat-treated with a digester to perform delignification and the like, followed by bleaching or the like.

  The fiber diameter of the cellulose before defibration used in the present invention is generally about a number average fiber diameter of a few millimeters after subjecting the above-mentioned cellulose-containing material to a general purification treatment. For example, in the case of cellulose obtained by refining a chip or the like having a size of several centimeters, it is preferable to further perform mechanical treatment with a disintegrator such as a refiner or beater so that the average fiber diameter is 100 nm or less.

[Modification process]
The modified cellulose used in the present invention is a cellulose having a cellulose type I crystal structure modified with an aromatic ring-containing substituent. Here, the modification means that a hydroxyl group in cellulose is chemically modified by reacting with a chemical modifier.

<Modified substituent>
In the present invention, the functional group introduced into cellulose by chemical modification is an aromatic ring-containing substituent. Introducing an aromatic ring-containing substituent as a modified substituent is preferable for achieving easy defibration and high productivity.

The aromatic ring-containing substituent is a substituent derived from an aromatic ring-containing compound such as a hydrocarbon aromatic compound, a heterocyclic aromatic compound, or a non-benzenoid aromatic compound. Here, the hydrocarbon-based aromatic compound is a compound obtained by condensing 2 to 12, preferably 2 to 6, benzene rings, such as benzene, naphthalene, anthracene, etc., and a heterocyclic aromatic compound. Is a 5- to 10-membered heterocyclic monocycle such as furan, thiophene, pyrrole or imidazole, or 2 to 12, preferably 2 to 6 condensed ring compounds thereof. Non-benzenoid aromatic compounds include azulene, annulene, cyclopentadienyl anion, cycloheptatrienyl cation, tropolone, metallocene, acepreazilene and the like. In these, the substituent derived from a hydrocarbon-type aromatic compound is preferable, and the substituent derived from benzene, naphthalene, and anthracene is especially preferable.

  In these aromatic ring-containing compounds, the hydrogen may be substituted with an alkyl group having 1 to 12 carbon atoms. Further, it may be a compound in which two or more aromatic rings are connected by a single bond or an alkylene group having 1 to 3 carbon atoms.

  The substituent that binds the aromatic ring-containing compound and cellulose is not particularly limited as long as it reacts with the hydroxyl group of cellulose, but is preferably an ester group, an ether group, or a carbamate group, and particularly preferably an ester group. preferable.

  That is, in the present invention, the aromatic ring-containing substituent of the modified substituent introduced into cellulose is preferably a benzoyl group, a naphthoyl group, an anthroyl group or the like, and particularly preferably a benzoyl group.

<Chemical modifier>
The method for modifying cellulose with the above-described modifying substituent is not particularly limited, and there is a method of reacting cellulose with a chemical modifier as described below. Although there are no particular limitations on the reaction conditions, a solvent, a catalyst, or the like may be used, or heating, decompression, or the like may be performed as necessary. This modification method will be described in detail in the section <Modification method> described later.

  As a kind of chemical modifier, for example, when an ester group is formed as a substituent for binding the above-described aromatic ring-containing compound and cellulose, an acid, an acid anhydride, a halogenating reagent, or the like forms an ether group In the case where a cyclic ether such as a phenol compound, phenoxysilane, or oxirane (epoxy) forms a carbamate group, an isocyanate or the like may be used.

  Examples of the acid that is a chemical modifier that forms an ester group include benzoic acid and naphthalenecarboxylic acid, and examples of the acid anhydride include benzoic anhydride and phthalic anhydride.

  Examples of the halogenating reagent include benzoyl halide and naphthoyl halide.

  Examples of the phenolic compound that is a chemical modifier that forms an ether group include phenol and naphthol, and phenoxysilane and cyclic ethers such as phenyloxirane (epoxy).

  Examples of the isocyanate that is a chemical modifier that forms a carbamate group include phenyl isocyanate.

  Among these, benzoyl halide, naphthoyl halide, and benzoic anhydride are particularly preferable.

  These chemical modifiers may be used alone or in combination of two or more.

<Modification method>
When the modified cellulose is used as a cellulose composite material in applications requiring transparency, it is necessary to fibrillate the cellulose into fine fibers. In the method for producing a modified cellulose fiber dispersion of the present invention, cellulose modification is performed on cellulose before defibration obtained by purifying the aforementioned cellulose-containing material. When the cellulose obtained after purification is modified and then defibrated, it is easy to defibrate and the filtration time for dehydration is shortened, which is preferable in terms of productivity. On the other hand, when modification is performed after the refined cellulose is fibrillated into fine fibers, labor is required to remove water. For this reason, it is preferable to modify the cellulose after purification and before defibration.

  Although chemical modification can be carried out in the usual manner, since cellulose after purification is usually in a water-containing state, this water can be replaced with a reaction solvent or the like to suppress the reaction between the chemical modifier and water as much as possible. is important. In addition, if drying is performed to remove water here, it is difficult to proceed with further miniaturization, so it is not preferable to include a drying step.

  That is, chemical modification can be performed by reacting the above-described chemical modifier with the above-described chemical modifier according to a conventional method on the purified cellulose that has been substituted with a reaction solvent or the like as necessary. At this time, if necessary, a solvent or a catalyst may be used, or heating, decompression, or the like may be performed. As the solvent, it is preferable to use a polar solvent that does not inhibit esterification.

Examples of the catalyst include pyridine, N, N-dimethylaminopyridine, triethylamine, sodium hydride, tert-butyllithium, lithium diisopropylamide, potassium te
rt-butoxide, sodium methoxide, sodium ethoxide, sodium hydroxide,
A basic catalyst such as sodium acetate or an acidic catalyst such as acetic acid, sulfuric acid or perchloric acid can be used. It is preferable to use a basic catalyst such as pyridine in order to increase the reaction rate and prevent the polymerization degree from decreasing. Sodium acetate is preferable in that there is no problem of coloring the cellulose by chemical modification and the modification rate can be increased by raising the reaction temperature. In addition, perchloric acid or sulfuric acid is preferred in that there is no problem of cellulose coloring due to chemical modification, and the modification rate can be increased under reaction conditions with a small amount of chemical modifier added at room temperature for a short time.

As the temperature condition at the time of reaction, if it is too high, there is a concern about yellowing of cellulose, a decrease in polymerization degree, etc., and if it is too low, the reaction rate decreases, so 10 to 130 ° C. is preferable. The reaction time is usually from several minutes to several tens of hours depending on the chemical modifier used and the target modification rate.

<Modification rate>
The modification rate here refers to the proportion of all hydroxyl groups in cellulose modified, and the modification rate can be measured by the following titration method.

(Method of measuring the modification rate)
0.05 g of the modified cellulose fiber or cellulose sheet is precisely weighed, and 6 ml of methanol and 2 ml of distilled water are added thereto. This is stirred at 60-70 ° C. for 30 minutes, and then 10 ml of 0.05N aqueous sodium hydroxide solution is added. The mixture is stirred at 60 to 70 ° C. for 15 minutes and further stirred at room temperature for one day. Titrate with 0.02N aqueous hydrochloric acid using phenolphthalein.
Here, from the amount Z (ml) of the 0.02N hydrochloric acid aqueous solution required for the titration, the number of moles Q of the substituent introduced by chemical modification is obtained by the following formula.
Q (mol) = 0.05 (N) × 10 (ml) / 1000
−0.02 (N) × Z (ml) / 1000
The relationship between the number of moles Q of the substituent and the modification rate X (mol%) is calculated by the following formula (cellulose = (C ₆ O ₅ H ₁₀ ) _n = (162.14) _n , repeating unit. Number of hydroxyl groups per piece = 3, molecular weight of OH = 17). In the following, T is the molecular weight of the substituent.

Solving this, it is as follows.

  The modification rate of the modified cellulose used in the present invention is preferably 9 mol% or less, more preferably 7 mol% or less, preferably 3 mol% or more, more preferably 5 mol%, based on the total hydroxyl groups of cellulose. That's it.

By chemically modifying cellulose with an aromatic ring-containing substituent, the decomposition temperature of the cellulose is increased, heat resistance is increased, and coloring during heating is preferably reduced. In particular, an aromatic ring-containing substituent is introduced as a modified substituent. Thus, as described above, it is possible to improve easy defibration and high productivity, which is preferable. However, if the modification rate is too high, the crystal structure of cellulose is destroyed and the crystallinity is lowered, so that there is a problem that the linear expansion coefficient of the resulting composite material becomes large, which is not preferable.
Further, if the modification rate is too low, the above effect due to the introduction of the aromatic ring-containing substituent cannot be sufficiently obtained, the hydrophilicity becomes high, and the filtration time at the time of dehydration becomes long. The moisture content of the cellulose fiber is undesirably high. In particular, when wood is used as the cellulose raw material, if the modification rate is low, it is not preferable because it is colored when heated in the post-treatment of the composite.

[Defibration process]
In order to obtain a transparent cellulose composite material, it is necessary to defibrate cellulose into fine fibers (cellulose nanofibers). A method for performing a defibrating step in order to obtain fine cellulose fibers from the modified cellulose will be described below.

The specific method of the defibration process is not particularly limited, but for example, a cellulose concentration of 0.1
Water, water-soluble organic solvent (this water-soluble organic solvent will be described in detail in the section of <Post-treatment> described later), acid or alkali aqueous solution, Ceramic beads having a diameter of about 1 mm are placed in a modified cellulose dispersion (hereinafter referred to as “modified cellulose dispersion”) prepared using a surfactant aqueous solution, an inorganic salt aqueous solution, etc., and a paint shaker or a bead mill is used. For example, a method of defibrating cellulose by applying vibration.

Cellulose fibers can also be obtained by blending with a blender-type disperser or slits rotating at high speed, using a cellulose dispersion such as shearing force (high-speed rotating homogenizer) or by suddenly reducing pressure from high pressure. Examples include a method in which a shearing force is generated in the middle (high pressure homogenizer method), a method using a counter-impact type disperser (Masuko Sangyo) such as the massomizer X, and the like. In particular, high-speed rotation homogenizer and high-pressure homogenizer treatment are preferable because of high defibration efficiency.

  In the case of defibration by these treatments, the solid content (modified cellulose) concentration of the modified cellulose dispersion is preferably 0.2% by weight to 10% by weight, particularly 0.3% by weight to 6% by weight. . If the solid content concentration in the modified cellulose dispersion to be subjected to this defibrating process is too low, the amount of liquid will increase with respect to the amount of modified cellulose to be treated, and the efficiency will be poor, and if the solid content concentration is too high, the fluidity will be poor The concentration of the modified cellulose dispersion subjected to the defibrating treatment is adjusted by adding water as appropriate.

  In the case of a high-speed rotation homogenizer, the higher the rotation speed, the higher the fibrillation efficiency due to the applied shear force. For example, the rotation speed is preferably 10,000 rpm or more, more preferably 15000 rpm or more, and particularly preferably 20000 rpm or more. The time is preferably 1 minute or longer, more preferably 5 minutes or longer, and particularly preferably 10 minutes or longer. When heat is generated by shearing, it is preferable to cool the solution so that the liquid temperature does not exceed 50 ° C. Moreover, it is preferable to stir or circulate so that a shearing force is applied uniformly to the dispersion.

  In the case of using a high-pressure homogenizer, the modified cellulose dispersion is pressurized with a pressure intensifier, ejected from a nozzle having a pore diameter of 50 μm or more and 200 μm or less, and a pressure difference is generated by reducing the pressure from a high pressure. The modified cellulose is defibrated by the cleavage phenomenon caused by this pressure difference. Here, when the pressure under the high pressure condition is low, or when the pressure difference from the high pressure to the decompression condition is small, the defibrating efficiency is lowered, and it is necessary to increase the number of repeated ejections to obtain a desired fiber diameter. Absent. In addition, even when the pore diameter of the pores through which the modified cellulose dispersion is ejected is too large, a sufficient fibrillation effect cannot be obtained.In this case, even if the ejection treatment is repeated, the desired fiber diameter can be obtained. There is also a possibility that the modified cellulose fiber cannot be obtained.

  By repeating the ejection of the modified cellulose dispersion a plurality of times as necessary, the degree of refinement can be increased and cellulose fibers having a desired fiber diameter can be obtained. The number of repetitions (pass number) is usually 1 or more, preferably 3 or more, and usually 20 or less, preferably 15 or less. As the number of passes increases, the degree of miniaturization can be increased. However, an excessively large number of passes is not preferable because the cost increases.

Although there is no restriction | limiting in particular in the temperature at the time of ejection (temperature of a modified cellulose dispersion liquid), Usually, they are 5 degreeC or more and 100 degrees C or less. If this temperature is too high, there is a possibility that deterioration of the apparatus, specifically, a liquid feed pump, a high-pressure seal part, etc. may be accelerated.
The number of the ejection nozzles may be one or two, and the ejected cellulose may be hit against a wall, ball, or ring provided at the ejection destination. Furthermore, when there are two nozzles, celluloses may collide with each other at the ejection destination.

[Modified cellulose fiber dispersion]
<Average fiber diameter>
The modified cellulose fiber dispersion defibrated by the above method (hereinafter simply referred to as “modified cellulose fiber dispersion of the present invention”, and the modified cellulose in this modified cellulose fiber dispersion is referred to as “modified cellulose of the present invention”. The fiber diameter of the cellulose fibers in the medium can be measured and determined by observing with SEM, TEM or the like after drying and removing the dispersion medium in the dispersion.
In the present invention, the average fiber diameter (number average fiber diameter) of the fibrillated modified cellulose fiber is 100 nm or less in order to obtain a highly transparent cellulose composite material. Is preferably 80 nm or less, and particularly preferably 50 nm or less. In addition, the minimum of this average fiber diameter is 4 nm or more normally.

<Cellulose type I crystal>
The cellulose fiber contained in the modified cellulose fiber dispersion of the present invention has cellulose I type crystals.

Cellulose type I crystal structure is, for example, “Encyclopedia of Cellulose” published by Asakura Shoten. 81-P. 86, or P.I. 93-99, and most natural cellulose has a cellulose I type crystal structure. On the other hand, not cellulose I type crystal structure but cellulose fibers of, for example, cellulose II, III, and IV type are derived from cellulose having cellulose I type crystal structure. Above all, the I-type crystal structure has a higher crystal elastic modulus than other structures.
The present invention is characterized in that fine cellulose fibers are provided by cellulose fibers having a cellulose I-type crystal structure. When it is an I-type crystal, a composite material having a low linear expansion coefficient and a high elastic modulus can be obtained when a composite material of cellulose fibers and a matrix is used.

  The fact that the cellulose fiber has the I-type crystal structure is a typical peak at two positions near 2θ = 14-17 ° and 2θ = 22-23 ° in the diffraction profile obtained by wide-angle X-ray diffraction image measurement. Can be identified.

<Thermal decomposition temperature>
The modified cellulose fiber contained in the modified cellulose fiber dispersion of the present invention preferably has a thermal decomposition temperature measured by the following method of 300 ° C. or higher, particularly 330 ° C. or higher. When this temperature is low, sufficient heat resistance cannot be obtained, which is not preferable.

(Measurement method of thermal decomposition temperature)
The modified cellulose fiber was conditioned at a temperature of 23 ° C. and a humidity of 50% for 48 hours or more, and this was converted to TG-D
The intersection of tangents obtained from TG (thermogravimetry) when the temperature was raised from room temperature to 600 ° C at 10 ° C / min using TA (differential thermogravimetric simultaneous measurement device) was determined as the pyrolysis temperature. It was.

<Post-processing>
The modified cellulose fiber dispersion of the present invention can be appropriately subjected to adjustment of the dispersion medium (solvent) concentration, substitution of the dispersion medium, addition of various additives, etc., after passing through the defibrating step. .

  Since the defibrating liquid after the defibrating step basically uses water as a dispersion medium, when water is used as a dispersion medium (solvent), it can be diluted as it is or with water. In addition, an organic solvent other than water can be added, and the organic solvent can be added and then concentrated to a desired composition ratio. When a solvent other than water is used, the solvent must be replaced. In this case, after adding a solvent, it is preferable to remove water out of the system by concentration. Care should be taken when concentrating so that the system does not become non-uniform. When the inside of the system becomes non-uniform, the cellulose fibers may be aggregated, and the haze of the resulting cellulose composite material is increased, so care must be taken.

  The solvent used as the dispersion medium is preferably water and / or a water-soluble organic solvent. That is, since the defibrating process is basically performed using water and / or a water-soluble organic solvent as a dispersion medium, in order to replace the solvent of the defibrating liquid after the defibrating process with a water-insoluble organic solvent. A large amount of solvent and time are not preferable for substitution.

  The water-soluble organic solvent as used herein refers to a solvent that maintains a uniform appearance even after the flow has subsided when gently mixed with the same volume of pure water at 20 degrees Celsius at one atmospheric pressure. Specific examples of the water-soluble organic solvent include monovalent alcohols such as n-propyl alcohol, isopropyl alcohol, t-butyl alcohol, and allyl alcohol; ethylene glycol, butyl glycol, t-butyl glycol, methyl diglycol, Polyhydric alcohols (glycols) such as ethyl diglycol, butyl diglycol, methyldipropylene glycol, glycerin; 1-methoxy-2-propanol, 2-ethoxyethanol, 2-n-butoxyethanol, 3-methoxybutanol, 3-methyl-3-methoxybutanol, ethylene glycol monomethyl ether, ethylene glycol dimethyl ether, ethylene glycol monophenyl ether, propylene glycol monomethyl ether, propylene glycol dimethyl ester Ether, diethylene glycol monomethyl ether, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, diethylene glycol monoethyl ether, diethylene glycol diethyl ether, diethylene glycol monobutyl ether, diethylene glycol butyl methyl ether, diethylene glycol dibutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, triethylene glycol Monomethyl ether, triethylene glycol dimethyl ether, triethylene glycol butyl methyl ether, tripropylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, polyethylene glycol monomethyl ether, Alkyl ethers of the above glycols such as reethylene glycol dimethyl ether; Esters such as diethylene glycol monobutyl ether acetate, ethylene glycol monomethyl ether acetate and ethyl lactate; Ethers such as tetrahydrofuran and 1,4-dioxane; Ketones such as diacetone alcohol Nitrogenous solvents such as acetonitrile, pyridine, N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone; organic acids such as acetic acid, acrylic acid, methacrylic acid, butyric acid; .

[productivity]
Cellulose modified with an aromatic ring-containing substituent is less defibrated as described below compared to unmodified cellulose into which no modified substituent is introduced and cellulose modified with an aliphatic substituent described in Patent Document 1. Excellent defibration in processing. Therefore, when the defibrating process is performed under the same conditions as the conventional product, fine fibers having a smaller fiber diameter can be obtained. For this reason, after reducing the fibrillation treatment, it is possible to obtain ultrafine cellulose fibers effective for improving the transparency and the like of the cellulose composite material.

  In addition, in the production of a cellulose sheet to be described later, as shown in Examples below, the modified cellulose fiber dispersion obtained by the method of the present invention is a dispersion of unmodified cellulose fibers. It is much shorter than the above, and even shorter than the dispersion of cellulose fibers modified with an aliphatic substituent.

  Although the details of the reason why the filtration time during sheeting is reduced in this way by the modified cellulose fiber dispersion obtained by the method of the present invention are not clear, the aromatic ring-containing substituent is more hydrophobic than the aliphatic substituent. It is considered that the introduction of an aromatic ring-containing substituent causes the cellulose fibers to be smoothly filtered and separated from the aqueous dispersion of cellulose fibers. In addition, since the aromatic ring-containing substituent has a bulky steric structure, it is considered that distortion occurs between the fibers, and a finer fiber is more easily obtained than the aliphatic substituent.

  In addition, the filtration time of an Example and a comparative example of a postscript is a thing of a laboratory level, and pressure reduction or pressure filtration of a smaller differential pressure is performed with respect to a larger amount of cellulose dispersion liquid by industrial mass production. In this case, the difference in the filtration time is very large.

  As described above, the modified cellulose fiber contained in the modified cellulose fiber dispersion of the present invention is effective for improving the productivity of a cellulose composite material using the modified cellulose fiber.

[2] Method for Producing Modified Cellulose Sheet When the modified cellulose fiber of the present invention is used as a cellulose composite material, it can be used after being formed into a sheet shape. By using a cellulose sheet, a cellulose composite material can be impregnated with a resin, or a cellulose composite material can be formed between resin sheets. By using the modified cellulose fiber dispersion of the present invention that has been subjected to the above-described defibrating process for producing a modified cellulose sheet, a cellulose composite material having high transparency, a low linear expansion coefficient, and a high elastic modulus can be obtained, which is preferable. In this case, the modified cellulose fiber dispersion of the present invention subjected to the above-described defibrating process is made by paper, specifically, the modified cellulose fiber dispersion of the present invention is filtered or applied to an appropriate substrate. And a cellulose sheet can be manufactured by setting it as a sheet form.

[Paper making process]
When the cellulose sheet is produced by filtering the modified cellulose fiber dispersion of the present invention, the cellulose concentration of the modified cellulose fiber dispersion of the present invention used for filtration is 0.01% by weight or more, preferably 0. 0%. It is preferable that the content is 05% by weight or more, more preferably 0.1% by weight or more. If the cellulose concentration is too low, filtration takes an enormous amount of time, which is not preferable. The concentration of the modified cellulose fiber dispersion of the present invention is 1.5% by weight or less, preferably 1.2% by weight or less, more preferably 1.0% by weight or less. If the cellulose concentration is too high, a uniform sheet cannot be obtained, which is not preferable.

  Moreover, as a filter cloth used for filtration, it is important that the refined cellulose fiber does not pass through and the filtration rate is not too slow. As such a filter cloth, a sheet made of an organic polymer, a woven fabric, and a porous membrane are preferable. The organic polymer is preferably a non-cellulose organic polymer such as polyethylene terephthalate, polyethylene, polypropylene, polytetrafluoroethylene (PTFE) or the like.

  Specific examples of the filter cloth include a polytetrafluoroethylene porous membrane having a pore diameter of 0.1 to 20 μm, for example, 1 μm, and a polyethylene terephthalate or polyethylene fabric having a pore diameter of 0.1 to 20 μm, for example, 1 μm.

  The cellulose sheet can have various porosity depending on the production method. Examples of a method for obtaining a cellulose sheet having a high porosity include a method of finally replacing water in an object to be filtered on a filter cloth with an organic solvent such as alcohol in a papermaking process (film formation process by filtration). . In this method, water is removed by filtration, and an organic solvent such as alcohol is added when the cellulose content of the material to be filtered on the filter cloth reaches 5 to 99% by weight. Alternatively, after adding the modified cellulose fiber dispersion of the present invention to a filtration device, an organic solvent such as alcohol can be added to the upper part of the filtered dispersion by gently pouring the organic solvent such as alcohol at the end of the filtration. Can be substituted.

  The organic solvent such as alcohol used here is not particularly limited, but for example, alcohols such as methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, acetone, methyl ethyl ketone, tetrahydrofuran, cyclohexane 1 type, or 2 or more types of organic solvents, such as toluene and carbon tetrachloride. When using a water-insoluble organic solvent, it is preferable to use a water-soluble organic solvent or a mixed solvent with the water-soluble organic solvent, and then replace with a water-insoluble organic solvent.

  In this paper making process (film formation process by filtration), by using the modified cellulose fiber dispersion of the present invention, a dispersion of cellulose fiber modified with other unmodified cellulose fibers or aliphatic substituents and In comparison, when the obtained sheet can be filtered at a high speed and the obtained sheet is made into a cellulose composite material, a highly transparent cellulose composite material can be obtained.

  After the filtration, drying is performed. This drying may be air drying, vacuum drying, or pressure drying. Moreover, you may heat-dry. When heating, the temperature is preferably 50 ° C or higher, more preferably 80 ° C or higher, 250 ° C or lower is more preferable, and 150 ° C or lower is more preferable. If the heating temperature is too low, drying may take time or drying may be insufficient. If the heating temperature is too high, the cellulose sheet may be colored or the cellulose may be decomposed. Moreover, when pressurizing, 0.01 MPa or more is preferable, 0.1 MPa or more is more preferable, 5 MPa or less is preferable, and 1 MPa or less is more preferable. If the pressure is too low, drying may be insufficient, and if the pressure is too high, the cellulose sheet may be crushed or cellulose may be decomposed.

  As a method for obtaining a cellulose sheet having a small porosity, drying is performed without performing substitution with the above-mentioned organic solvent after filtration or application of the modified cellulose fiber dispersion of the present invention. Drying is as described above.

  In addition, the chemical modification of cellulose can be further performed after the cellulose sheet is thus formed. In this case, chemical modification may be performed after the sheet obtained as described above is dried, or may be performed before the sheet is dried. The cellulose sheet is reacted with the chemical modifier according to the above-described method, then washed with water and / or an organic solvent, and then dried to obtain a modified cellulose sheet.

  The thickness of the modified cellulose sheet thus produced is not particularly limited, but is preferably 100 nm or more and 1 cm or less. More preferably, they are 1 micrometer or more and 1 mm or less, More preferably, they are 10 micrometers or more and 500 micrometers or less, Especially preferably, they are 30 micrometers or more and 250 micrometers or less. The thickness of the modified cellulose sheet is preferably thicker than the above lower limit from the viewpoints of production stability and strength, and is preferably thinner than the upper limit from the viewpoint of productivity, uniformity, and impregnation property of the matrix material described later.

[3] Method for Producing Modified Cellulose Particles The modified cellulose fiber contained in the modified cellulose fiber dispersion of the present invention can be used in the form of particles (hereinafter, cellulose fibers are referred to as “cellulose particles”). May be referred to.) These modified cellulose particles are particularly suitably used when they are combined with a thermoplastic resin by kneading. By taking advantage of their properties such as high elastic modulus, low linear expansion coefficient, and surface smoothness, various structural materials, especially surface It is useful for automotive panels with excellent design and exterior wall panels for buildings.

  As a method for granulating the modified cellulose fiber, the modified cellulose fiber dispersion of the present invention in which the modified cellulose fiber is dispersed in water, a water-soluble organic solvent, an acid or alkali aqueous solution, a surfactant aqueous solution, an inorganic salt aqueous solution, or the like. For example, a method of removing the dispersion medium and granulating by spraying from a spray nozzle or the like using a known spray drying apparatus may be mentioned. Specific examples of the injection method include a method using a rotating disk, a method using a pressure nozzle, and a method using a two-fluid nozzle. You may dry the particle | grains obtained by spray-drying further using another drying apparatus. In this case, infrared rays or microwaves can be used as the thermal energy source.

  Further, modified cellulose particles can also be obtained by freeze-drying and then pulverizing the modified cellulose fiber dispersion of the present invention. In this case, specifically, there is a method in which the modified cellulose fiber dispersion of the present invention is cooled with liquid nitrogen and then pulverized with a grinder or a rotary blade.

  Since such modified cellulose fibers are made into modified cellulose fibers after chemical modification, productivity is higher than when the above-mentioned chemical modification is performed after cellulose fibers that have not been modified are made into cellulose particles. This is preferable.

  The particle size of the modified cellulose particles is not particularly limited, but is preferably 1 μm or more and 1 mm or less. The particle size is more preferably 5 μm or more and 100 μm or less, and particularly preferably 5 μm or more and 50 μm or less. When the particle size of the modified cellulose particles is too large, poor dispersion occurs when they are combined with a polymer, and when they are too small, they are fluffy and difficult to handle.

[4] Manufacturing method of cellulose composite material [Composite method]
The modified cellulose fiber dispersion of the present invention can be made into a cellulose composite material by complexing with a polymer as a modified cellulose sheet or modified cellulose particles or as it is.

  Thus, the cellulose composite material of the present invention is a modified cellulose fiber contained in the modified cellulose fiber dispersion of the present invention, or a modified cellulose sheet formed from the same, or a modified cellulose particle formed from the same, preferably modified. Cellulose sheets or modified cellulose particles are composited with a polymer other than cellulose as a matrix material, and various display substrate materials and solar cells are utilized by taking advantage of their high transparency, low linear expansion coefficient, and non-coloring properties. It is useful for battery substrates, window materials, etc., and by taking advantage of its properties such as high elastic modulus, low linear expansion coefficient, and surface smoothness, various structural materials, especially automotive panels with excellent surface design, Useful for exterior wall panels in buildings.

  Hereinafter, the manufacturing method of the cellulose composite material of this invention formed by complexing the modified cellulose fiber contained in the modified cellulose fiber dispersion of this invention with polymers other than cellulose which is a matrix material will be described.

  Here, the matrix material refers to a polymer material or a precursor thereof (for example, a monomer) that is bonded to a cellulose sheet, filled with voids, or kneaded with granulated cellulose particles.

The polymer or the precursor thereof as a matrix material of the cellulose composite material of the present invention is one of the base materials of the cellulose composite material, and can produce a cellulose composite material satisfying suitable physical properties described later. If there is, there is no particular limitation.
Suitable as the matrix material is a thermoplastic resin that becomes a fluid liquid by heating, a thermosetting resin that polymerizes by heating, and is cured by irradiation with active energy rays such as ultraviolet rays and electron beams. , At least one resin (polymer material) selected from active energy ray-curable resins and the like, or a precursor thereof.
In the present invention, the precursor of the polymer material is a so-called monomer or oligomer, for example, each monomer described later as a polymerization or copolymerization component in the section of thermoplastic resin (hereinafter referred to as thermoplastic resin precursor). And the precursors described later in the section of thermosetting resin / photocurable resin.

As a method for producing a cellulose composite material of the present invention, that is, a method of contacting and compositing a matrix material with a modified cellulose sheet, modified cellulose particles, etc. (hereinafter sometimes referred to as “cellulose sheet, particles, etc.”) The following methods (a) to (h) are mentioned.
(A) Method of impregnating cellulose sheet, particles, etc. with liquid thermoplastic resin precursor and polymerizing (b) Impregnating cellulose sheet, particles, etc. with thermosetting resin precursor or active energy ray curable resin precursor (C) Cellulose sheet, particle and the like contain resin solution (one or more solutes selected from thermoplastic resin, thermoplastic resin precursor, thermosetting resin precursor, and photocurable resin precursor) A method of impregnating a solution) and drying, and then adhering with a hot press or the like, and polymerizing and curing if necessary (d) impregnating a cellulose sheet, particles or the like with a thermoplastic resin melt and adhering with a hot press or the like Method (e) A method in which thermoplastic resin sheets (or films) and cellulose sheets are alternately arranged and adhered with a heating press or the like (f) One side or both sides of the cellulose sheet A method of polymerizing and curing a liquid thermoplastic resin precursor, thermosetting resin precursor or active energy ray curable resin precursor on a resin sheet (thermoplastic resin, heat A solution containing at least one solute selected from a plastic resin precursor, a thermosetting resin precursor, and a photocurable resin precursor), removing the solvent, and then polymerizing and curing as necessary. (H) A method of melt-kneading cellulose particles and a thermoplastic resin and then molding the sheet into a desired shape

  The modified cellulose fiber dispersion of the present invention is combined with a polymer other than cellulose in water without drying, and then the water is removed or the organic solvent is replaced with another organic solvent from the water. A cellulose composite material can also be produced by complexing with a polymer other than cellulose, and then removing the organic solvent.

  Among them, the methods (a), (b), (c), (d), (e), (f), and (g) are preferable for the modified cellulose sheet, and (h) for the modified cellulose particles. This method is preferred.

(A) As a method of polymerizing by impregnating a cellulose sheet, particles or the like with a liquid thermoplastic resin precursor, the cellulose monomer or oligomer is impregnated with a polymerizable monomer or oligomer, and the monomer is polymerized by heat treatment or the like. The method of obtaining a cellulose composite material by this is mentioned. Generally, a polymerization catalyst used for polymerization of monomers can be used as a polymerization initiator.

(B) As a method of impregnating a cellulose sheet, particles or the like with a thermosetting resin precursor or an active energy ray curable resin precursor and polymerizing and curing, a thermosetting resin precursor such as an epoxy resin monomer, or an acrylic resin A cellulose sheet or particle is impregnated with a mixture of an active energy ray curable resin precursor such as a monomer and a curing agent, and the thermosetting resin precursor or the active energy ray curable resin precursor is formed by heat or active energy rays or the like. The method of obtaining a cellulose composite material by hardening is mentioned.

(C) One or more solutes (hereinafter referred to as “resin component”) selected from a resin solution (thermoplastic resin, thermoplastic resin precursor, thermosetting resin precursor, and photocurable resin precursor) in a cellulose sheet, particles, etc. After the impregnated solution is dried with a hot press or the like, the resin component is dissolved in a solvent in which the resin component is dissolved. A method of obtaining a cellulose composite material by impregnating the solution into a cellulose sheet, particles or the like and drying it. In this case, a method of obtaining a higher-performance cellulose composite material by adhering the voids in which the solvent is dried by a heating press or the like after drying is mentioned. In the case of a photo-curing resin, polymerization curing with active energy rays or the like is further performed as necessary.
The solvent for dissolving the resin component may be selected in consideration of the affinity with the modified cellulose fiber and the solubility of the resin component, and specifically, those exemplified as the dispersion medium of the modified cellulose fiber dispersion What is necessary is just to select from the inside according to the solubility of a resin component.

(D) As a method of impregnating a cellulose sheet, particles or the like with a thermoplastic resin melt and closely adhering with a hot press or the like, the thermoplastic resin is melted by heat treatment at a glass transition temperature or higher or a melting point or higher, There is a method in which a cellulose composite material is obtained by impregnating a cellulose sheet, particles, and the like, and closely adhering with a hot press or the like. The heat treatment is desirably performed under pressure, and the use of equipment having a vacuum heating press function is effective.

(E) As a method of alternately arranging a thermoplastic resin sheet (or film) and a cellulose sheet and closely adhering them with a hot press or the like, a sheet (or film) of a thermoplastic resin is disposed on one side or both sides of the modified cellulose sheet. A method of laminating a thermoplastic resin sheet (or film) and a modified cellulose sheet by heating or pressing as necessary is mentioned. In this case, an adhesive or a primer may be applied in advance to the surface of the modified cellulose sheet and bonded. A method of passing between two pressurized rolls or a method of pressing in a vacuum state can be used so that bubbles are not embraced at the time of bonding.

(F) One or both sides of the modified cellulose sheet may be applied by applying a liquid thermoplastic resin precursor, thermosetting resin precursor or active energy ray curable resin precursor to one side or both sides of the cellulose sheet and curing. Applying a thermosetting resin precursor formulated with a thermal polymerization initiator to the resin and curing it by heating, or adhering both, active energy rays formulated with a photopolymerization initiator on one or both sides of the modified cellulose sheet An example is a method in which an curable resin precursor is applied and then irradiated with an active energy ray such as ultraviolet rays to be cured. After applying the heat or active energy ray-curable resin precursor to the modified cellulose sheet, it may be cured after forming a multilayer structure such as by further stacking the modified cellulose sheet.

(G) One or both surfaces of the cellulose sheet contain a resin solution (one or more solutes (resin components) selected from a thermoplastic resin, a thermoplastic resin precursor, a thermosetting resin precursor, and a photocurable resin precursor). As a method of compounding by applying a solution), removing the solvent, and then polymerizing and curing as necessary, a resin solution in which a resin component soluble in the solvent is dissolved in the solvent is prepared, and the modified cellulose The method of apply | coating to the single side | surface or both surfaces of a sheet | seat, and removing a solvent by heating is mentioned. In the case of a photo-curing resin, polymerization curing with active energy rays or the like is further performed as necessary.
Here, the solvent for dissolving the resin component may be selected in consideration of the affinity with the modified cellulose fiber and the solubility of the resin component. Specifically, those exemplified as the dispersion medium for the modified cellulose fiber dispersion From the above, it may be selected according to the solubility of the resin component.

  A laminate can be obtained by stacking a plurality of cellulose composite materials of a modified cellulose sheet and a resin thus produced. In that case, you may laminate | stack the resin sheet which does not contain the cellulose composite material containing a modified cellulose sheet. In order to adhere the cellulose composite materials or the resin sheet and the cellulose composite material, an adhesive may be applied or an adhesive sheet may be interposed. Moreover, it can also integrate by adding a heat press process to a laminated body.

(H) After melt-kneading the cellulose particles and the thermoplastic resin, a method of forming into a sheet shape or a desired shape includes a method of melting the modified cellulose particles and the thermoplastic resin after dry blending, a method of melt-kneading , Etc. are preferred. In the method of melting after dry blending, both are uniformly mixed with a tumbler blender, ribbon blender, V-type blender, Henschel mixer, etc., and then an additive such as an antioxidant used as necessary is added to the mixture. It is added and made into a cellulose composite material through a molten state. Specifically, for example, the mixture is simply melted or melt-kneaded by a single or twin screw extruder, roll, Banbury mixer, kneader, Brabender, or the like. Thereafter, it is extruded from a T-die and formed into a sheet shape, or injected into a mold to form a desired shape.

[Specific examples of matrix materials]
Specific examples and preferred examples of the matrix material used in the cellulose composite material of the present invention are exemplified below, but the matrix material used in the present invention is not limited to the following. In addition, the thermoplastic resin, thermosetting resin, and light (active energy ray) curable resin in the present invention can be used in combination of two or more.

  In the present invention, among the following matrix materials (polymer materials or precursors thereof), in the case of polymer materials or precursors, the polymer is an amorphous compound having a high glass transition temperature (Tg). A polymer is preferable for obtaining a highly durable cellulose composite material excellent in transparency. Among them, the degree of amorphousness is preferably 10% or less, particularly 5% or less in terms of crystallinity, and Tg is preferably room temperature or higher, particularly 100 ° C. or higher, particularly 130 ° C. or higher. The polymer Tg can be determined by a general method. For example, it is obtained by measurement by the DSC method. The degree of crystallinity of the polymer can be calculated from the density of the amorphous part and the crystalline part, and can also be calculated from the tan δ, which is the ratio of the elastic modulus to the viscosity, by dynamic viscoelasticity measurement. .

<Thermoplastic resin>
The thermoplastic resin is not particularly limited as long as the physical properties of the cellulose composite material described later can be satisfied. For example, styrene resin, acrylic resin, aromatic polycarbonate resin, aliphatic polycarbonate resin, aromatic Polyester resin, aliphatic polyester resin, aliphatic polyolefin resin, cyclic olefin resin, polyamide resin, polyphenylene ether resin, thermoplastic polyimide resin, polyacetal resin, polysulfone resin, amorphous fluorine resin Etc.

  Examples of the styrenic resin include polymers and copolymers such as styrene, chlorostyrene, divinylbenzene, and α-methylstyrene.

  Examples of the acrylic resin include polymers and copolymers such as (meth) acrylic acid, (meth) acrylonitrile, (meth) acrylic acid ester, and (meth) acrylamide. Here, “(meth) acryl” means “acryl and / or methacryl”.

  Examples of (meth) acrylic acid esters include (meth) acrylic acid alkyl esters, (meth) acrylic acid monomers having a cycloalkyl ester group, and (meth) acrylic acid alkoxyalkyl esters. Examples of the (meth) acrylic acid alkyl ester include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, ( Examples include benzyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, hydroxyethyl (meth) acrylate, and the like. Examples of the (meth) acrylic acid monomer having a cycloalkyl group include cyclohexyl (meth) acrylate and isobornyl (meth) acrylate. Examples of (meth) acrylic acid alkoxyalkyl esters include 2-methoxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate, and 2-butoxyethyl (meth) acrylate.

  As (meth) acrylamide, (meth) acrylamide, N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N- Examples thereof include N-substituted (meth) acrylamides such as isopropyl (meth) acrylamide and Nt-octyl (meth) acrylamide.

  Aromatic polycarbonate resin is produced by the reaction of one or more bisphenols that can contain polyhydric phenols having three or more valences as copolymerization components and carbonates such as bisalkyl carbonate, bisaryl carbonate, and phosgene. Copolymer. If necessary, an aromatic dicarboxylic acid such as terephthalic acid or isophthalic acid or a derivative thereof (for example, an aromatic dicarboxylic acid diester or an aromatic dicarboxylic acid chloride) is used as a copolymerization component to form an aromatic polyester carbonate. May be used.

  Examples of the bisphenols include bisphenol A, bisphenol C, bisphenol E, bisphenol F, bisphenol M, bisphenol P, bisphenol S, and bisphenol Z (for abbreviations, refer to the Aldrich reagent catalog), among which bisphenol A and bisphenol Z (Where the central carbon participates in the cyclohexane ring) is preferred, and bisphenol A is particularly preferred. Examples of copolymerizable trihydric phenols include 1,1,1- (4-hydroxyphenyl) ethane and phloroglucinol.

  The aliphatic polycarbonate resin is a copolymer produced by a reaction between an aliphatic diol component and / or an alicyclic diol component and a carbonic ester such as bisalkyl carbonate or phosgene. Examples of the alicyclic diol include cyclohexane dimethanol and isosorbite.

  Examples of aromatic polyester resins include copolymers of diols such as ethylene glycol, propylene glycol, and 1,4-butanediol and aromatic carboxylic acids such as terephthalic acid. Moreover, the copolymer of diols, such as bisphenol A, and aromatic carboxylic acids, such as a terephthalic acid and isophthalic acid, is mentioned like polyarylate.

  Examples of the aliphatic polyester-based resin include a copolymer of the diol and an aliphatic dicarboxylic acid such as succinic acid and valeric acid, and a copolymer of hydroxydicarboxylic acid such as glycolic acid and lactic acid.

Specific examples of the aliphatic polyolefin resin include homopolymers of α-olefins having about 2 to 8 carbon atoms such as ethylene, propylene and 1-butene, those α-olefins, ethylene, propylene, 1-butene, 3-methyl-1-butene, 1-pentene, 4-methyl-1-pentene, 4,4-dimethyl-1-pentene, 1-hexene, 4-methyl-1-hexene, 1-heptene, Examples thereof include binary or ternary copolymers with other α-olefins having about 2 to 18 carbon atoms such as 1-octene, 1-decene and 1-octadecene. Specifically, ethylene homopolymers such as branched low density polyethylene and linear high density polyethylene, ethylene-propylene copolymer, ethylene-1-butene copolymer, ethylene-propylene-1-butene copolymer Ethylene resins such as ethylene-4-methyl-1-pentene copolymer, ethylene-1-hexene copolymer, ethylene-1-heptene copolymer, ethylene-1-octene copolymer, and propylene homopolymer Propylene resins such as propylene-ethylene copolymer, propylene-ethylene-1-butene copolymer, 1-butene homopolymer, 1-butene-ethylene copolymer, 1-butene-propylene copolymer, etc. 1-butene resin, 4-methyl-1-pentene homopolymer, 4-methyl-1-pentene-ethylene copolymer, etc. Resins such as chill-1-pentene-based resin, and a copolymer of ethylene and other α- olefins, copolymers of 1-butene and another α- olefin.
Further, for example, 1,4-hexadiene, 4-methyl-1,4-hexadiene, 5-methyl-1,4-hexadiene, 6-methyl-1,5-heptadiene, 1,4-octadiene, 7-methyl- 1,6-octadiene, cyclohexadiene, cyclooctadiene, dicyclopentadiene, 5-methylene-2-norbornene, 5-ethylidene-2-norbornene, 5-butylidene-2-norbornene, 5-isopropenyl-2-norbornene, etc. And binary or ternary copolymers with non-conjugated dienes. Specifically, an olefin rubber such as an ethylene-propylene copolymer, an ethylene-propylene-nonconjugated diene copolymer, an ethylene-1-butene copolymer, an ethylene-1-butene-nonconjugated diene copolymer is used. Can be mentioned. Two or more of these olefin polymers may be used in combination.

  The cyclic olefin-based resin is a polymer containing a cyclic olefin skeleton in a polymer chain, such as norbornene or cyclohexadiene, or a copolymer containing these. For example, a norbornene-based resin composed of a repeating unit of a norbornene skeleton or a copolymer of a norbornene skeleton and a methylene skeleton can be mentioned, and commercially available products include “Arton” manufactured by JSR, “Xennex” and “Zeonor” manufactured by Nippon Zeon. "Appel" manufactured by Mitsui Chemicals, "Topas" manufactured by Chicona, etc.

  Examples of polyamide resins include aliphatic amide resins such as 6,6-nylon, 6-nylon, 11-nylon, 12-nylon, 4,6-nylon, 6,10-nylon, 6,12-nylon, An aromatic polyamide comprising an aromatic diamine such as phenylenediamine and an aromatic dicarboxylic acid such as terephthaloyl chloride or isophthaloyl chloride or a derivative thereof can be mentioned.

  Examples of the polyphenylene ether resin include poly (2,6-dimethyl-1,4-phenylene ether), poly (2-methyl-6-ethyl-1,4-phenylene ether), and poly (2,6-dichloro ether). -1,4-phenylene ether), and a copolymer of 2,6-dimethylphenol and other phenols.

  Examples of polyimide resins include pyromellitic acid-type imides such as polymellitic anhydride and 4,4′-diaminodiphenyl ether, aromatic diamines and diisocyanates such as anhydrous chlorotrimellitic acid and p-phenylenediamine, and the like. Trimellitic acid-type polyimide, biphenyltetracarboxylic acid, 4,4'-diaminodiphenyl ether, biphenyl-type polyimide consisting of p-phenylenediamine, benzophenone tetracarboxylic acid and 4,4'-diaminodiphenyl ether Examples thereof include benzophenone-type polyimides made of, bismaleimide, bismaleimide-type polyimides made of 4,4′-diaminodiphenylmethane, and the like.

  Examples of the polyacetal resin include a homopolymer having an oxymethylene structure as a unit structure and a copolymer containing an oxyethylene unit.

  Examples of the polysulfone resin include copolymers such as 4,4'-dichlorodiphenylsulfone and bisphenol A.

  Examples of the amorphous fluorine-based resin include homopolymers or copolymers such as tetrafluoroethylene, hexafluoropropylene, chlorotrifluoroethylene, vinylidene fluoride, vinyl fluoride, and perfluoroalkyl vinyl ether.

  These thermoplastic resins may be used individually by 1 type, and may use 2 or more types together.

<Curable resin>
A thermosetting resin and an active energy ray-curable resin mean a resin cured product obtained by curing a precursor. Here, the precursor means a substance that is liquid, semi-solid or solid at room temperature and exhibits fluidity at room temperature or under heating. These can be an insoluble and infusible resin formed by forming a network-like three-dimensional structure while causing a polymerization reaction or a crosslinking reaction to increase the molecular weight by the action of a curing agent, a catalyst, heat or light. The resin cured product means a resin obtained by curing the thermosetting resin precursor or the active energy ray curable resin precursor.

<Thermosetting resin>
The thermosetting resin precursor in the present invention is not particularly limited, but epoxy resin, acrylic resin, oxetane resin, phenol resin, urea resin, melamine resin, unsaturated polyester resin, silicon resin, polyurethane resin, diallyl phthalate resin, etc. The precursor of this is mentioned.

  The epoxy resin precursor refers to an organic compound having at least one epoxy group. The number of epoxy groups in the epoxy resin precursor is preferably 1 or more and 7 or less per molecule, and more preferably 2 or more per molecule. Here, the number of epoxy groups per molecule of the precursor is obtained by dividing the total number of epoxy groups in the epoxy resin precursor by the total number of molecules in the epoxy resin.

  It does not specifically limit as said epoxy resin precursor, For example, the precursor of the epoxy resin shown below is mentioned. These epoxy resin precursors may be used alone or in combination of two or more. The epoxy resin is usually obtained by curing the epoxy resin precursor using a curing agent.

Examples of the epoxy resin precursor include bisphenol type epoxy resins such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, and cresol novolak type epoxy resin. And other precursors such as novolak-type epoxy resins, aromatic epoxy resins such as trisphenolmethane triglycidyl ether, and hydrogenated products and brominated products thereof.
3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, 3,4-epoxy-2-methylcyclohexyl-3,4-epoxy-2-methylcyclohexanecarboxylate, bis (3,4-epoxy Cyclohexyl) adipate, bis (3,4-epoxycyclohexyl) methyl adipate, bis (3,4-epoxy-6-methylcyclohexyl) methyl adipate, bis (2,3-epoxycyclopentyl) ether and other alicyclic epoxy resin precursors The body is mentioned.
Also, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin triglycidyl ether, trimethylolpropane triglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl Examples include aliphatic epoxy resin precursors such as ethers, polyglycidyl ethers of long-chain polyols containing polyoxyalkylene glycols containing 2 to 9 (preferably 2 to 4) carbon atoms alkylene groups, polytetramethylene ether glycols, and the like. .
In addition, glycidyl ester type epoxy resins such as phthalic acid diglycidyl ester, tetrahydrophthalic acid diglycidyl ester, hexadrophthalic acid diglycidyl ester, diglycidyl-p-oxybenzoic acid, salicylic acid glycidyl ether-glycidyl ester, dimer acid glycidyl ester, etc. Examples thereof include precursors and hydrogenated products thereof.
Further, triglycidyl isocyanurate, N, N′-diglycidyl derivative of cyclic alkylene urea, precursor of glycidyl amine type epoxy resin of N, N, O-triglycidyl derivative of p-aminophenol, and hydrogenated products thereof. Can be mentioned.
Moreover, the copolymer etc. of radical polymerizable monomers, such as glycidyl (meth) acrylate, ethylene, vinyl acetate, (meth) acrylic acid ester, etc. are mentioned. In addition, a polymer mainly composed of a conjugated diene compound such as epoxidized polybutadiene or a partially hydrogenated polymer obtained by epoxidizing an unsaturated carbon double bond may be used. Further, a polymer block mainly composed of a vinyl aromatic compound, such as epoxidized SBS, and a polymer block mainly composed of a conjugated diene compound or a polymer block of a partially hydrogenated product thereof are contained in the same molecule. Examples include epoxidized unsaturated carbon double bonds of a conjugated diene compound in a block copolymer. Moreover, the polyester resin etc. which have 1 or more per molecule, Preferably 2 or more epoxy groups are mentioned. Further, urethane-modified epoxy resins and polycaprolactone-modified epoxy resins in which urethane bonds and polycaprolactone bonds are introduced into the structure of the epoxy resin are exemplified. Examples of the modified epoxy resin include a rubber-modified epoxy resin in which a rubber component such as NBR, CTBN, polybutadiene, and acrylic rubber is contained in the epoxy resin. In addition to the epoxy resin, a resin or oligomer having at least one oxirane ring may be added. Moreover, the thermosetting resin and composition containing a fluorene containing epoxy resin, a fluorene group, or its hardened | cured material is also mentioned. These fluorene-containing epoxy resins are suitably used because of their high heat resistance.

  The curing agent used for the curing reaction of the epoxy resin precursor is not particularly limited. For example, amine compounds, compounds such as polyaminoamide compounds synthesized from amine compounds, tertiary amine compounds, imidazole compounds, hydrazide compounds, Examples include melamine compounds, acid anhydrides, phenol compounds, thermal latent cationic polymerization catalysts, photolatent cationic polymerization initiators, dicyanamide and derivatives thereof. These curing agents may be used alone or in combination of two or more.

  The acrylic resin precursor includes a monofunctional (meth) acrylate compound having one (meth) acryloyl group in the molecule, and a polyfunctional (meth) acrylate having two or three (meth) acryloyl groups in the molecule. Examples thereof include compounds, acrylic acid derivatives, acrylate compounds having 4 to 8 (meth) acryloyl groups in the molecule, epoxy (meth) acrylate compounds, (meth) acrylate compounds having a urethane bond, and the like.

  Monofunctional (meth) acrylate compounds having one (meth) acryloyl group in the molecule include methyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, phenyl (meth) acrylate, benzyl (meth) acrylate, Examples thereof include cyclohexyl (meth) acrylate and alkyl (meth) acrylate having an alkyl group having 1 to 30 carbon atoms.

In particular, mono (meth) acrylate having an alicyclic skeleton has high heat resistance and can be suitably used. Specific examples of the alicyclic skeleton mono (meth) acrylate compound include (hydroxy-acryloyloxy) tricyclo [5.2.1.0 ^2,6 ] decane, (hydroxy-methacryloyloxy) tricyclo [5.2.1]. .0 ^2,6] decane, (hydroxy - acryloyloxy) pentacyclo [6.5.1.1 ^{3, 6.} 0 ^2,7 . 0 ^9,13 ] pentadecane, (hydroxy-methacryloyloxy) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, (hydroxymethyl-acryloyloxymethyl) tricyclo [5.2.1.0 ^2,6 ] decane, (hydroxymethyl-methacryloyloxymethyl) tricyclo [5.2.1.0 ^2,6 Decane, (hydroxymethyl-acryloyloxymethyl) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, (hydroxymethyl-methacryloyloxymethyl) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, (hydroxyethyl-acryloyloxyethyl) tricyclo [5.2.1.0 ^2,6 ] decane, (hydroxyethyl-methacryloyloxyethyl) tricyclo [5.2.1.0 ^2,6 ] Decane, (hydroxyethyl-acryloyloxyethyl) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, (hydroxyethyl-methacryloyloxyethyl) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane and the like. Mixtures of these can also be used.

Polyfunctional (meth) acrylate compounds having 2 or 3 (meth) acryloyl groups in the molecule include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, Tetraethylene glycol or higher polyethylene glycol di (meth) acrylate, 1,3-butylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, alkyl having 1 to 30 carbon atoms in the alkyl group Diol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 2-hydroxy-1,3-di (meth) acryloxypropane, 2,2-bis [4- (meth) acryloyloxyphenyl] propane, tri Methylol propane tri ) Acrylate, bis (hydroxy) tricyclo [5.2.1.0 ^2,6 ] decane = diacrylate, bis (hydroxy) tricyclo [5.2.1.0 ^2,6 ] decane = dimethacrylate, bis ( Hydroxy) tricyclo [5.2.1.0 ^2,6 ] decane = acrylate methacrylate, bis (hydroxy) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane = diacrylate, bis (hydroxy) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane = dimethacrylate, bis (hydroxy) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane = acrylate methacrylate, 2,2-bis [4- (β- (meth) acryloyloxyethoxy) phenyl] propane, 2,2-bis [4- (β- (meth) acryloyloxyethoxy) Cyclohexyl] propane, 1,4-bis [(meth) acryloyloxymethyl] cyclohexane, and the like.

  Examples of (meth) acrylic acid derivatives other than esters include acrylamide, methacrylamide, acrylonitrile, methacrylonitrile and the like.

Among these, an alicyclic ring skeleton bis (meth) acrylate compound is preferably used.
For example, bis (acryloyloxy) tricyclo [5.2.1.0 ^2,6 ] decane, bis (methacryloyloxy) tricyclo [5.2.1.0 ^2,6 ] decane, (acryloyloxy-methacryloyloxy) tricyclo [5.2.1.0 ^2,6 ] decane, bis (acryloyloxy) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, bis (methacryloyloxy) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, (acryloyloxy-methacryloyloxy) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, bis (acryloyloxymethyl) tricyclo [5.2.1.0 ^2,6 ] decane, bis (methacryloyloxymethyl) tricyclo [5.2.1.0 ^2,6 ] decane, ( Acryloyloxymethyl-methacryloyloxymethyl) tricyclo [5.2.1.0 ^2,6 ] decane, bis (acryloyloxymethyl) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, bis (methacryloyloxymethyl) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, (acryloyloxymethyl-methacryloyloxymethyl) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, bis (acryloyloxyethyl) tricyclo [5.2.1.0 ^2,6 ] decane, bis (methacryloyloxyethyl) tricyclo [5.2.1.0 ^2,6 ] decane, ( Acryloyloxyethyl-methacryloyloxyethyl) tricyclo [5.2.1.0 ^2,6 ] decane, bis (acryloyloxyethyl) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, bis (methacryloyloxyethyl) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, (acryloyloxyethyl-methacryloyloxyethyl) pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13 ] pentadecane, etc., and mixtures thereof.

Of these, bis (acryloyloxymethyl) tricyclo [5.2.1.0 ^2,6 ] decane, bis (methacryloyloxymethyl) tricyclo [5.2.1.0 ^2,6 ] decane and (acryloyloxymethyl) -Methacryloyloxymethyl) tricyclo [5.2.1.0 ^2,6 ] decane is preferred. Two or more of these bis (meth) acrylates can be used in combination.

As the (meth) acrylate having 4 to 8 (meth) acryloyl groups in the molecule, a (meth) acrylic ester of a polyol can be used.
Specifically, pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipenta Erythritol tri (meth) acrylate, tripentaerythritol octa (meth) acrylate, tripentaerythritol septa (meth) acrylate, tripentaerythritol hexa (meth) acrylate, tripentaerythritol penta (meth) acrylate, tripentaerythritol tetra (meth) Examples include acrylate and tripentaerythritol tri (meth) acrylate.

Specific examples of the epoxy (meth) acrylate include, for example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolac type epoxy resin, compound having an alicyclic epoxy group, and bisphenol A type propylene oxide addition type terminal glycidyl. A reaction product of ether, fluorene epoxy resin or the like and (meth) acrylic acid can be mentioned.
Specifically, bisphenol A diglycidyl ether = di (meth) acrylate, bisphenol A dipropylene oxide diglycidyl ether = di (meth) acrylate, ethylene glycol diglycidyl ether = di (meth) acrylate, propylene glycol diglycidyl ether = Di (meth) acrylate, neopentyl glycol diglycidyl ether = di (meth) acrylate, 1,6-hexanediol diglycidyl ether = di (meth) acrylate, glycerin diglycidyl ether = di (meth) acrylate, trimethylolpropane tri Glycidyl ether = tri (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, 3,4-epoxycyclohexylmethyl (meth) acrylate DOO, 3,4-epoxycyclohexyl ethyl (meth) acrylate, 3,4-epoxycyclohexyl-butyl (meth) acrylate, 3,4-epoxycyclohexylmethyl-amino (meth) acrylate.

  Examples of the (meth) acrylate having a urethane bond in the molecule include urethane oligomers having 2 to 10 (preferably 2 to 5) (meth) acryloyl groups in one molecule. For example, there is a (meth) acryloyl group-containing urethane oligomer produced by reacting a urethane prepolymer obtained by reacting diols and diisocyanates with a hydroxy group-containing (meth) acrylate.

The diols used here include ring-opening copolymerization of polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyhexamethylene glycol, polyheptamethylene glycol, polydecamethylene glycol, or two or more ion-polymerizable cyclic compounds. The polyether diol obtained is mentioned.
Examples of the ion polymerizable cyclic compound include ethylene oxide, propylene oxide, butene-1-oxide, isobutene oxide, 3,3-bischloromethyloxetane, tetrahydrofuran, dioxane, trioxane, tetraoxane, cyclohexene oxide, styrene oxide, epichlorohydrin, glycidyl methacrylate, Examples include cyclic ethers such as allyl glycidyl ether, allyl glycidyl carbonate, butadiene monooxide, isoprene monooxide, vinyl oxetane, vinyl tetrahydrofuran, vinylcyclohexene oxide, phenyl glycidyl ether, butyl glycidyl ether, and benzoic acid glycidyl ester. Further, a polyether obtained by ring-opening copolymerization of the ionic polymerizable cyclic compound with a cyclic imine such as ethyleneimine, a cyclic lactone acid such as β-propiolactone or glycolic acid lactide, or dimethylcyclopolysiloxane. Diols can also be used.
Specific combinations of the two or more ion-polymerizable cyclic compounds include tetrahydrofuran and propylene oxide, tetrahydrofuran and 2-methyltetrahydrofuran, tetrahydrofuran and 3-methyltetrahydrofuran, tetrahydrofuran and ethylene oxide, propylene oxide and ethylene oxide, butene oxide and ethylene oxide. Etc. The ring-opening copolymer of these ion-polymerizable cyclic compounds may be bonded at random or may be bonded in a block form.

  These polyether diols described so far include, for example, PTMG1000, PTMG2000 (manufactured by Mitsubishi Chemical Corporation), PPG1000, EXCENOL2020, 1020 (manufactured by Asahi Ohrin Co., Ltd.), PEG1000, Unisafe DC1100, DC1800 ( As described above, manufactured by NOF Corporation), PPTG2000, PPTG1000, PTG400, PTGL2000 (above, manufactured by Hodogaya Chemical Co., Ltd.), Z-3001-4, Z-3001-5, PBG2000A, PBG2000B (above, Daiichi Kogyo Seiyaku Co., Ltd.) It can also be obtained as a commercial product such as (made by Co., Ltd.).

  In addition to the above polyether diols, polyester diols, polycarbonate diols, polycaprolactone diols, and the like can be given. These diols can be used in combination with polyether diols. The polymerization mode of these structural units is not particularly limited, and any of random polymerization, block polymerization, and graft polymerization may be used. Examples of the polyester diol used here include ethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol, tetramethylene glycol, polytetramethylene glycol, 1,6-hexanediol, neopentyl glycol, 1,4-cyclohexanedimethanol, 3 -Polyhydric alcohols such as methyl-1,5-pentanediol, 1,9-nonanediol, 2-methyl-1,8-octanediol, phthalic acid, isophthalic acid, terephthalic acid, maleic acid, fumaric acid, adipine Mention may be made of polyester polyols obtained by reacting acids and polybasic acids such as sebacic acid. Commercially available products include Kurapol P-2010, PMIPA, PKA-A, PKA-A2, PNA-2000 (above, manufactured by Kuraray Co., Ltd.) and the like.

  Examples of the polycarbonate diol include 1,6-hexane polycarbonate, and commercially available products include DN-980, 981, 982, 983 (manufactured by Nippon Polyurethane Co., Ltd.), PC-8000 (US PPG ( Etc.).

  Furthermore, as polycaprolactone diol, for example, ε-caprolactone and ethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol, tetramethylene glycol, polytetramethylene glycol, 1,2-polybutylene glycol, 1,6-hexanediol, neo Examples thereof include polycaprolactone diols obtained by reacting divalent diols such as pentyl glycol, 1,4-cyclohexanedimethanol and 1,4-butanediol. These diols are commercially available from Plaxel 205, 205AL, 212, 212AL, 220, 220AL (above, manufactured by Daicel Corporation).

  Many diols other than those described above can also be used. Examples of such diols include ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, 1,4-cyclohexanedimethanol, and bisphenol A. Ethylene oxide addition diol, bisphenol A butylene oxide addition diol, bisphenol F ethylene oxide addition diol, bisphenol F butylene oxide addition diol, hydrogenated bisphenol A ethylene oxide addition diol, hydrogenated bisphenol A butylene oxide addition diol, Ethylene oxide addition diol of hydrogenated bisphenol F, Butylene oxide addition diol of hydrogenated bisphenol F, Dimethylolation of dicyclopentadiene Products, tricyclodecane dimethanol, β-methyl-δ-valerolactone, hydroxy-terminated polybutadiene, hydroxy-terminated hydrogenated polybutadiene, castor oil-modified polyol, polydimethylsiloxane-terminated diol compound, polydimethylsiloxane carbitol-modified polyol, etc. It is done.

  In addition to using the diol as described above, it is also possible to use a diamine together with a diol having a polyoxyalkylene structure. Examples of such a diamine include ethylenediamine, tetramethylenediamine, hexamethylenediamine, and paraphenylenediamine. Diamines such as 4,4'-diaminodiphenylmethane, diamines containing heteroatoms, polyether diamines, and the like.

  A preferable diol includes polytetramethylene ether glycol which is a polymer of 1,4-butanediol. The preferred molecular weight of this diol is usually 50 to 15,000, particularly 500 to 3,000, in terms of number average molecular weight.

On the other hand, examples of diisocyanates include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, 1,5-naphthalene diisocyanate, and m-phenylene. Diisocyanate, p-phenylene diisocyanate, 3,3'-dimethyl-4,4'-diphenyl metadiisocyanate, 4,4'-diphenylmethane diisocyanate, 3,3'-dimethylphenylene diisocyanate, 4,4'-biphenylene diisocyanate, 1, 6-hexamethylene diisocyanate, methylene dicyclohexyl diisocyanate, methylene bis (4-cyclohexyl isocyanate), 2,2,4-trimethylhexamethylene diisocyanate, 1,4- Hexamethylene diisocyanate, bis (2-isocyanatoethyl) fumarate, 6-isopropyl-1,3-phenyl diisocyanate, isophorone diisocyanate, norbornane diisocyanate, lysine diisocyanate, and the like. These diisocyanates may be used singly or in combination of two or more.
Of these, diisocyanates having an alicyclic skeleton such as isophorone diisocyanate, norbornane diisocyanate, and methylene dicyclohexyl diisocyanate are preferably used.

  Examples of the hydroxy group-containing (meth) acrylate compound used in the reaction include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, and 2-hydroxy-3. -Phenyloxypropyl (meth) acrylate, 1,4-butanediol mono (meth) acrylate, 2-hydroxyalkyl (meth) acryloyl phosphate, 4-hydroxycyclohexyl (meth) acrylate, 1,6-hexanediol mono (meth) ) Acrylate, neopentyl glycol mono (meth) acrylate, trimethylolpropane di (meth) acrylate, trimethylolethane di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipen Erythritol penta (meth) acrylate, further the alkyl glycidyl ether, allyl glycidyl ether, may also include compounds obtained by addition reaction of glycidyl (meth) glycidyl group-containing compounds such as acrylates and (meth) acrylic acid. Of these, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and the like are particularly preferable.

  Commercially available urethane oligomers include EB2ECRYL220 (Daicel Cytec), Art Resin UN-3320HA (Negami Kogyo), Art Resin UN-3320HB (Negami Kogyo), Art Resin UN-3320HC (Negami Kogyo), Art Resin UN-330 ( Negami Kogyo) and Art Resin UN-901T (Negami Kogyo), NK-oligo U-4HA (Shin Nakamura Chemical), NK-oligo U-6HA (Shin Nakamura Chemical), NK-oligo U-324A (Shin Nakamura Chemical), NK-oligo U-15HA (Shin Nakamura Chemical), NK-oligo U-108A (Shin Nakamura Chemical), NK-oligo U-200AX (Shin Nakamura Chemical), NK-oligo U-122P (Shin Nakamura Chemical), NK- Oligo U-5201 (Shin Nakamura Chemical), NK-Oligo U-340AX (Shin Nakamura Chemical), NK-Oligo U-511 (Shin Nakamura Chemical), NK-Oligo U-512 (Shin Nakamura Chemical), NK-Oligo U -311 (Shin Nakamura Chemical), NK-oligo UA-W1 (Shin Nakamura Chemical), NK-oligo UA-W2 (Shin Nakamura Chemical), NK-oligo UA-W3 (Shin Nakamura Chemical), NK-oligo UA-W4 (Shin Nakamura Chemical , NK-oligo UA-4000 (Shin-Nakamura Chemical), NK-oligo UA-100 (Shin-Nakamura Chemical), Purple light UV-1400B (Nippon Synthetic Chemical Industry), Purple light UV-1700B (Nippon Synthetic Chemical Industry), Purple light UV- 6300B (Nippon Synthetic Chemical Industry), purple light UV-7550B (Nippon Synthetic Chemical Industry), purple light UV-7600B (Nippon Synthetic Chemical Industry), purple light UV-7605B (Nippon Synthetic Chemical Industry), purple light UV-7610B (Nippon Synthetic Chemical Industry) ), Purple light UV-7620EA (Nippon Synthetic Chemical Industry), purple light UV-7630B (Nippon Synthetic Chemical Industry), purple light UV-7640B (Nippon Synthetic Chemical Industry), purple light UV-6630B (Nippon Synthetic Chemical Industry), purple light UV-7000B (Nippon Synthetic Chemical Industry), Purple Light UV-7510B (Nippon Synthetic Chemical Industry), Purple Light UV-7461TE (Nippon Synthetic Chemical Industry), Purple Light UV-3000B (Nippon Synthetic Chemical Industry), Purple Light UV-3200B (Nippon Synthetic Chemical Industry) , Purple light UV-3210EA (Nippon Synthetic Chemical Industry), purple light UV-3310B (Nippon Synthetic Chemical Industry), purple light UV-3500BA (Nippon Synthetic Chemical Industry), purple light UV-3520T L (Nippon Synthetic Chemical Industry), purple light UV-3700B (Nippon Synthetic Chemical Industry), purple light UV-6100B (Nippon Synthetic Chemical Industry), purple light UV-6640B (Nippon Synthetic Chemical Industry), etc. can be used.

  The number average molecular weight of the (meth) acrylate having a urethane bond in the molecule is preferably 1,000 to 100,000, and more preferably 2,000 to 10,000.

  Among these, urethane acrylates having methylene dicyclohexyl diisocyanate and polytetramethylene ether glycol are excellent in terms of transparency, low birefringence, flexibility and the like, and can be suitably used.

  Examples of the oxetane resin precursor include compounds having at least one oxetane ring. The number of oxetane rings in the oxetane resin precursor is preferably 1 or more and 4 or less per molecule. Examples of the compound having one oxetane in the molecule include 3-ethyl-3-hydroxymethyloxetane, 3-ethyl-3- (phenoxymethyl) oxetane, and 3-ethyl-3- (2-ethylhexyloxymethyl) oxetane. , 3-ethyl {[-3- (triethoxysilyl) propoxy] methyl} oxetane, 3-ethyl-3-methacryloxymethyloxetane, and the like. Compounds having two oxetanes in the molecule include di [1-ethyl (3-oxetanyl)] methyl ether, 1,4-bis {[(3-ethyl-3-oxetanyl) methoxy] methyl} benzene, 4 , 4'-bis [(3-ethyl-3-oxetanyl) methoxymethyl] biphenyl, and the like. Examples of the compound having 3 to 4 oxetane rings include a branched polyalkyleneoxy group and a reaction product of a polysiloxy group and 3-alkyl-3-methyloxetane.

  The curing agent used for the curing reaction of the oxetane resin precursor is not particularly limited. For example, amine compounds, compounds such as polyaminoamide compounds synthesized from amine compounds, tertiary amine compounds, imidazole compounds, hydrazide compounds, Examples include melamine compounds, acid anhydrides, phenol compounds, thermal latent cationic polymerization catalysts, photolatent cationic polymerization initiators, dicyanamide and derivatives thereof. These curing agents may be used alone or in combination of two or more. In particular, the photocuring agent is preferably used from the viewpoint of effective use of energy. Here, the photo-curing agent is a compound that initiates cationic polymerization by irradiation with active energy rays, and examples thereof include diaryliodonium salts and triarylsulfonium salts.

  Examples of the phenol resin precursor include those obtained by reacting phenols such as phenol and cresol with formaldehyde and the like to synthesize novolak and the like and curing the resultant with hexamethylenetetramine or the like.

  Examples of the urea resin precursor include polymerization reaction products such as urea and formaldehyde.

  Examples of the melamine resin precursor include melamine and a polymerization reaction product such as formaldehyde.

  Examples of the unsaturated polyester resin include a resin obtained by dissolving an unsaturated polyester obtained from an unsaturated polybasic acid or the like and a polyhydric alcohol or the like in a monomer to be polymerized therewith, and the like.

  Examples of the silicon resin precursor include those having an organopolysiloxane as a main skeleton.

  Examples of the polyurethane resin precursor include polymerization reaction products composed of diols such as glycol and diisocyanate.

  Examples of the diallyl phthalate resin precursor include reactants comprising diallyl phthalate monomers and diallyl phthalate prepolymers.

  There are no particular limitations on the curing agent and curing catalyst of these thermosetting resins. Examples of the curing agent include polyfunctional amines, polyamides, acid anhydrides, and phenol resins, and examples of the curing catalyst include imidazole. It is done. These can be used alone or as a mixture of two or more.

<Active energy ray curable resin>
Although it does not specifically limit as active energy ray curable resin in this invention, Precursors, such as an epoxy resin illustrated in the description of the above-mentioned thermosetting resin, an acrylic resin, and an oxetane resin, are mentioned.

  Although there is no limitation in particular as a hardening | curing agent of these active energy ray hardening resin, For example, a diaryl iodonium salt, a triaryl sulfonium salt, etc. are mentioned.

<Other ingredients>
The above-mentioned thermosetting resin precursor and active energy ray curable resin precursor can be used as a curable composition appropriately blended with a chain transfer agent, an ultraviolet absorber, a filler, a silane coupling agent, and the like.

(Chain transfer agent)
For the purpose of allowing the reaction to proceed uniformly, the curable composition may contain a chain transfer agent.
As the chain transfer agent, for example, a polyfunctional mercaptan compound having two or more thiol groups in the molecule can be used, whereby moderate toughness can be imparted to the cured product. Examples of the mercaptan compound include pentaerythritol tetrakis (β-thiopropionate), pentaerythritol tetrakis (β-thioglycolate), trimethylolpropane tris (β-thiopropionate), trimethylolpropane tris (β- Thioglycolate), diethylene glycol bis (β-thiopropionate), diethylene glycol bis (β-thioglycolate), dipentaerythritol hexakis (β-thiopropionate), dipentaerythritol hexakis (β-thioglycolate) 2) to 6-valent thioglycolic acid ester or thiopropionic acid ester; tris [2- (β-thiopropionyloxy) ethyl] triisocyanurate, tris [2- (β-thioglyconyloxy) ethyl] Triisocyanate , Tris [2- (β-thiopropionyloxyethoxy) ethyl] triisocyanurate, tris [2- (β-thioglycolyloxyethoxy) ethyl] triisocyanurate, tris [2- (β-thiopropionyloxy) Ω-SH group-containing triisocyanurates such as propyl] triisocyanurate and tris [2- (β-thioglyconyloxy) propyl] triisocyanurate; benzene dimercaptan, xylylene dimercaptan, 4,4′-dimercaptodiphenyl Examples include α, ω-SH group-containing compounds such as sulfide. Among these, pentaerythritol tetrakis (β-thiopropionate), trimethylolpropane tris (β-thiopropionate), tris [2- (β-thiopropionyloxyethoxy) ethyl] triisocyanurate, and the like can be given. These may be used alone or in combination of two or more. When a mercaptan compound is added, it is usually contained in a proportion of 30% by weight or less with respect to the total of radically polymerizable compounds.

(UV absorber)
For the purpose of preventing coloring, the curable composition may contain an ultraviolet absorber. For example, the ultraviolet absorber is selected from a benzophenone ultraviolet absorber and a benzotriazole ultraviolet absorber. These may be used alone or in combination of two or more.
Specifically, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy-4-octadecyloxybenzophenone, 2,2′-dihydroxy-4 Benzophenone compounds such as -methoxybenzophenone and 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2- (2'-hydroxy-5-methylphenyl) benzotriazole, 2- (2'-hydroxy-3 ' , 5′-ditertiarybutylphenyl) benzotriazole, benzotriazole compounds such as 2- (2′-hydroxy-3′-tertiarybutyl-5′-methylphenyl) benzotriazole, and other malonate ester hostabin PR -25 (Clariant), Anil oxalate And other compounds such as Sandebore VSU (Clariant). When an ultraviolet absorber is added, it is usually contained at a ratio of 0.01 to 1 part by weight with respect to 100 parts by weight of the total of radically polymerizable compounds.

(Fillers other than cellulose)
Moreover, this curable composition may also contain fillers other than a cellulose fiber. Examples of the filler include inorganic particles and organic polymers. Specific examples include inorganic particles such as silica particles, titania particles and alumina particles, transparent cycloolefin polymers such as Zeonex (Nippon Zeon) and Arton (JSR), and general-purpose thermoplastic polymers such as polycarbonate and PMMA. . Among these, use of nano-sized silica particles is preferable because transparency can be maintained. In addition, it is preferable to use a polymer having a structure similar to that of the active energy ray-curable monomer because the polymer can be dissolved to a high concentration.

(Silane coupling agent)
Moreover, you may add a silane coupling agent to this curable composition. Examples of the silane coupling agent include vinyltrichlorosilane, vinyltris (β-methoxyethoxy) silane, vinyltriethoxysilane, vinyltrimethoxysilane, γ-((meth) acryloxypropyl) trimethoxysilane, β- (3 , 4epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β ( Aminoethyl) γ-aminopropylmethyldimethoxysilane, γ-aminopropyltrimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane and the like.
Among them, γ-((meth) acryloxypropyl) trimethoxysilane, γ-((meth) acryloxypropyl) methyldimethoxysilane, γ-((meth) acryloxypropyl) methyldiethoxysilane, γ-(( (Meth) acryloxypropyl) triethoxysilane, γ- (acryloxypropyl) trimethoxysilane and the like have a (meth) acryl group in the molecule and can be copolymerized with other monomers, which is preferable.
The silane coupling agent is contained in an amount of usually 0.1 to 50% by weight, preferably 1 to 20% by weight, based on the total of radically polymerizable compounds. If the blending amount is too small, the effect of containing it is not sufficiently obtained, and if it is too large, optical properties such as transparency of the cured product may be impaired.

<Curing process>
When a precursor of a polymer material (for example, a thermosetting resin precursor or an active energy ray curable resin precursor) is used as a matrix material, a curing process for curing the precursor is performed as necessary. May be.

  The curing method is appropriately selected depending on the type of precursor used, and examples thereof include heat curing and radiation curing. Radiation curing is preferable. Examples of the radiation include infrared rays, visible rays, ultraviolet rays, electron beams, and the like, preferably light. More preferred is light having a wavelength of about 200 nm to 450 nm, and even more preferred is ultraviolet light having a wavelength of 300 to 400 nm.

  Specifically, a method of adding a thermal polymerization initiator that generates radicals by heating to a precursor of a polymer material in advance and polymerizing by heating (hereinafter sometimes referred to as “thermal polymerization”), a polymer in advance A method in which a photopolymerization initiator that generates radicals by radiation such as ultraviolet rays is added to the precursor of the material and polymerized by irradiation with radiation (hereinafter sometimes referred to as “photopolymerization”), etc., and a thermal polymerization initiator And a photopolymerization initiator are added in advance and polymerized by a combination of heat and light. Photopolymerization is more preferred in the present invention.

  As the photopolymerization initiator, a photoradical generator is usually used. As the photoradical generator, a known compound that can be used for this purpose can be used. Examples include benzophenone, benzoin methyl ether, benzoin propyl ether, diethoxyacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2,6-dimethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, and the like. Among these, 2,4,6-trimethylbenzoyldiphenylphosphine oxide is preferable. These photopolymerization initiators may be used alone or in combination of two or more.

  The amount of the photopolymerization initiator used is 0.001 part by weight or more, preferably 0.01 part by weight or more, more preferably 0.05 part by weight or more when the total amount of radically polymerizable compounds is 100 parts by weight. is there. The upper limit is usually 1 part by weight or less, preferably 0.5 part by weight or less, more preferably 0.1 part by weight or less. When the addition amount of the photopolymerization initiator is too large, the polymerization proceeds rapidly, and not only the birefringence of the resulting cured product is increased, but also the hue is deteriorated. For example, when the amount of the initiator is 5 parts by weight, absorption of the initiator causes light to not reach the side opposite to the irradiation of the ultraviolet rays, resulting in an uncured portion. Further, it is colored yellow and the hue is markedly deteriorated. On the other hand, if the amount is too small, the polymerization may not proceed sufficiently even if ultraviolet irradiation is performed.

The amount of radiation irradiated upon curing is arbitrary as long as the photopolymerization initiator is in a range that generates radicals. If it is extremely small, the polymerization will be incomplete, and the heat resistance and mechanical properties of the cured product will not be sufficiently expressed. Conversely, if it is extremely excessive, the cured product will deteriorate due to light such as yellowing. , the type of the monomer composition and a photopolymerization initiator, according to the amount, the ultraviolet rays having a wavelength of 300 to 450 nm, preferably irradiated with 0.1 J / cm ² or more 200 J / cm ² or less. More preferably, irradiation is performed in the range of 1 J / cm ² or more and 20 J / cm ² . More preferably, the radiation is divided into a plurality of times. That is, when the first irradiation is performed for about 1/20 to 1/3 of the total irradiation amount and the necessary remaining amount is irradiated for the second and subsequent times, a cured product with smaller birefringence is obtained. Specific examples of the lamp to be used include a metal halide lamp, a high pressure mercury lamp lamp, an ultraviolet LED lamp and the like.

  In the case of simultaneously performing photopolymerization and thermal polymerization for the purpose of promptly completing the polymerization, curing is performed by heating in the range of 30 ° C. or more and 300 ° C. or less simultaneously with radiation irradiation. In this case, a thermal polymerization initiator may be added to complete the polymerization. However, if added in a large amount, the birefringence of the cured product is increased and the hue is deteriorated. Therefore, the thermal polymerization initiator can be radically polymerized. It is used so that it may become 0.1 to 2 weight% normally with respect to the sum total of a compound, More preferably, it is 0.3 to 1 weight%.

  Examples of the thermal polymerization initiator include hydroperoxide, dialkyl peroxide, peroxy ester, diacyl peroxide, peroxy carbonate, peroxy ketal, and ketone peroxide. Specifically, benzoyl peroxide, diisopropyl peroxy carbonate, t-butyl peroxy (2-ethylhexanoate) dicumyl peroxide, di-t-butyl peroxide, t-butyl peroxybenzoate, t-butyl hydro Peroxide, diisopropylbenzene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide and the like can be used. When thermal polymerization is initiated at the time of light irradiation, it becomes difficult to control the polymerization. Therefore, these thermal polymerization initiators preferably have a one-minute half-life temperature of 120 ° C. or higher. These polymerization initiators may be used alone or in combination of two or more.

[Laminated structure]
The cellulose composite material of the present invention may be a laminated structure of a layer of the modified cellulose fiber sheet of the present invention and a planar structure layer (for example, a sheet or a film) made of a polymer other than cellulose as described above. A laminated structure of the modified cellulose fiber sheet of the present invention and the cellulose composite material of the present invention may be used, and the number of laminated layers and the laminated structure are not particularly limited.

  In addition, the cellulose composite material of the present invention may be obtained by further laminating an inorganic film depending on its use, or may be obtained by further laminating an inorganic film on the above-mentioned laminate. .

The inorganic film used here is appropriately determined according to the use of the cellulose composite material, for example, metal such as platinum, silver, aluminum, gold, copper, silicon, ITO, SiO ₂ , SiN, SiOxNy, ZnO, etc., TFT The combination and the film thickness can be designed arbitrarily.

[Characteristics and physical properties of cellulose composite materials]
Hereinafter, suitable characteristics or physical properties of the cellulose composite material of the present invention will be described.

<Cellulose content>
The content of the modified cellulose fiber of the present invention in the cellulose composite material of the present invention is usually 1% by weight to 99% by weight, and the content of polymers other than cellulose is 1% by weight to 99% by weight. In order to express low linear expansion, it is necessary that the content of the modified cellulose fiber is 1% by weight or more and the content of a polymer other than cellulose is 99% by weight or less. In order to express transparency, it is necessary that the content of cellulose fibers is 99% by weight or less and the content of polymers other than cellulose is 1% by weight or more. A preferred range is 5% to 90% by weight of cellulose fibers, a polymer other than cellulose is 10% to 95% by weight, and a more preferred range is 10% to 80% by weight of cellulose fibers. The polymer other than cellulose is 20% by weight or more and 90% by weight or less. In particular, the content of cellulose is preferably 30% by weight or more and 70% by weight or less, and the content of polymers other than cellulose is preferably 30% by weight or more and 70% by weight or less.

  The content of the modified cellulose fiber and the polymer other than cellulose in the cellulose composite material can be determined, for example, from the weight of the modified cellulose fiber before complexing and the weight of the cellulose composite material after complexing. Alternatively, the cellulose composite material can be immersed in a solvent in which the polymer is soluble to remove only the polymer, and the weight can be determined from the weight of the remaining cellulose fibers. In addition, the functional group of a polymer or a cellulose fiber can also be quantified and determined using a method of determining from the specific gravity of the polymer, NMR, or IR.

<Thickness>
The thickness of the cellulose composite material of the present invention is preferably 10 μm or more and 10 cm or less, and by setting it to such a thickness, the strength as a structural material can be maintained. The thickness of the cellulose composite material is more preferably 50 μm to 1 cm, and still more preferably 80 μm to 250 μm.
The cellulose composite material of the present invention is, for example, a film shape (film shape) or a plate shape having such a thickness, but is not limited to a flat film or a flat plate, and may be a film shape or a plate shape having a curved surface. it can. Other irregular shapes may also be used. Further, the thickness is not necessarily uniform, and may be partially different.

<Coloring>
The cellulose composite material of the present invention is less colored.
Cellulose is sometimes yellowish by using raw materials derived from wood. In this case, there are a case where the cellulose itself is colored and a case where a substance other than the remaining cellulose is colored depending on the degree of purification. Generally, it is not colored at the stage of cellulose alone, but it may be colored by heating when it is combined with a polymer. The modified cellulose fiber and cellulose composite material of the present invention are less colored even when a heating step is performed. The degree of coloring of the cellulose composite material of the present invention is preferably 20 or less as a YI value, more preferably 15 or less, and further preferably 10 or less. The YI value can be measured using, for example, a color computer manufactured by Suga Test Instruments.

<Haze>
The cellulose composite material of the present invention can be a cellulose composite material having high transparency, that is, low haze. When used as various transparent materials, the haze value of the cellulose composite material is preferably 30 or less, more preferably 25 or less, and particularly preferably 20 or less. The haze is measured using, for example, a haze meter manufactured by Suga Test Instruments, and the value of C light is used.

<Total light transmittance>
When the cellulose composite material of the present invention is used as various transparent materials, the total light transmittance measured in the thickness direction of the cellulose composite material in accordance with JIS standard K7105 is 60% or more, more preferably 70% or more. It is preferable that it is 80% or more. If this total light transmittance is less than 60%, it becomes translucent or opaque, and it may be difficult to use it in applications requiring transparency. The total light transmittance can be measured, for example, for a cellulose composite material having a thickness of 10 to 100 μm, using a Suga Test Instruments haze meter, and the value of C light is used.

<Linear expansion coefficient>
The cellulose composite material of the present invention can be made into a cellulose composite material having a low linear expansion coefficient by using cellulose having a low linear expansion coefficient (elongation rate per 1K). The linear expansion coefficient of the cellulose composite material is preferably 1 to 50 ppm / K, more preferably 1 to 40 ppm / K, and particularly preferably 1 to 30 ppm / K.
In addition, a linear expansion coefficient is measured by the method described in the term of the below-mentioned Example.

<Tensile strength>
The tensile strength of the cellulose composite material of the present invention is preferably 40 MPa or more, more preferably 100 MPa or more. If the tensile strength is lower than 40 MPa, sufficient strength cannot be obtained, which may affect the use of a structural material or the like to which a force is applied.

<Tensile modulus>
The tensile elastic modulus of the cellulose composite material of the present invention is preferably 0.2 to 100 GPa, more preferably 1 to 50 GPa. When the tensile elastic modulus is lower than 0.2 GPa, sufficient strength cannot be obtained, which may affect the use of a structural material or the like to which a force is applied.

[Usage]
The cellulose composite material of the present invention has high transparency, high strength, low water absorption, high transparency, low coloration, and excellent optical properties. Therefore, the liquid crystal display, plasma display, organic EL display, field emission display, rear projection television. It is suitable as a display, a substrate or a panel. Moreover, it is suitable for substrates for solar cells such as silicon-based solar cells and dye-sensitized solar cells. The substrate may be laminated with a barrier film, ITO, TFT, or the like. Further, it is suitably used for window materials for automobiles, window materials for railway vehicles, window materials for houses, window materials for offices and factories, and the like. As the window material, a film such as a fluorine film or a hard coat film or a material having impact resistance or light resistance may be laminated as necessary.
Further, it can be used as a structure other than the transparent material utilizing the characteristics such as low linear expansion coefficient, high elasticity, and high strength. In particular, it is suitably used as automobile materials such as interior materials, outer plates, bumpers, etc., personal computer casings, home appliance parts, packaging materials, building materials, civil engineering materials, marine materials, and other industrial materials.

  Hereinafter, the present invention will be described more specifically with reference to production examples, examples, and comparative examples. However, the present invention is not limited to the following examples unless it exceeds the gist.

  In addition, the evaluation method of the physical property thru | or characteristic of the manufactured modified cellulose fiber and a cellulose composite material is as follows.

<Chemical modification rate of modified cellulose fiber>
0.05 g of the dried modified cellulose fiber was precisely weighed, 6 ml of methanol and 2 ml of distilled water were added thereto, stirred at 60 to 70 ° C. for 30 minutes, 10 ml of 0.05N aqueous sodium hydroxide solution was added, and 60 to 70 The mixture was stirred at ° C for 15 minutes and further stirred at room temperature for one day. This was titrated with 0.02N aqueous hydrochloric acid using phenolphthalein, and the chemical modification rate was calculated from the following formula.

これを解いていくと、以下の通りである。

Here, from the amount Z (ml) of the 0.02N hydrochloric acid aqueous solution required for the titration, the number of moles Q of the substituent introduced by chemical modification is obtained by the following formula.
Q (mol) = 0.05 (N) × 10 (ml) / 1000
−0.02 (N) × Z (ml) / 1000
The relationship between the number of moles Q of the substituent and the modification rate X (mol%) is calculated by the following formula (cellulose = (C ₆ O ₅ H ₁₀ ) _n = (162.14) _n , repeating unit. Number of hydroxyl groups per piece = 3, molecular weight of OH = 17). In the following, T is the molecular weight of the substituent.

Solving this, it is as follows.

<Thermal decomposition temperature of cellulose>
The cellulose sheet was conditioned at a temperature of 23 ° C. and a humidity of 50% for 48 hours or more, and the temperature was increased from room temperature to 600 ° C. at a rate of 10 ° C./min. The intersection of the tangent lines obtained from the TG at that time was defined as the thermal decomposition temperature.

<Average fiber diameter>
The fiber diameter of the cellulose fiber was measured and determined by observing with a SEM, TEM or the like. The average of 10 points excluding the maximum and minimum of 12 points extracted at random was defined as the average fiber diameter.

<Measurement of wide-angle X-ray diffraction image of cellulose>
Using an X-ray generator (“PW1700” manufactured by PANalytical) for the cellulose sheet, target Cu / Kα ray, monochromator, voltage 40 kV, current 30 mA, scanning angle (2θ) 3.0 to 50.0 °, step angle 0 Measurement was performed under the measurement condition of .05 °.

<Cellulose fiber content of cellulose composite material>
The cellulose fiber content (% by weight) was determined from the weight of the cellulose sheet used for the composite and the weight of the cellulose composite material.

<YI value of cellulose composite material>
The YI value was measured using a color computer manufactured by Suga Test Instruments.

<Haze of cellulose composite material>
The haze value by C light was measured using a Suga Test Instruments haze meter.

<Total light transmittance of cellulose composite material>
About the obtained cellulose composite material, based on JIS specification K7105, the total light transmittance by C light was measured using the Suga Test Instruments haze meter.

<Linear expansion coefficient of cellulose composite material>
The cellulose composite material was cut into 3 mm width × 40 mm length with a laser cutter.
This was stretched using a TMA6100 manufactured by SII in a tensile mode at a temperature of 5 ° C./min. And then from 180 ° C. to 25 ° C. at 5 ° C./min. At 25 ° C. and then from 25 ° C. to 180 ° C. at 5 ° C./min. The linear expansion coefficient was determined from the measured value from 60 ° C. to 100 ° C. during the second temperature increase.

<Tensile modulus of cellulose composite material>
The cellulose composite material was cut into a 10 mm width × 40 mm length with a laser cutter. This was subjected to DMA (dynamic viscoelasticity) measurement in tensile mode using DMS6100 manufactured by SII, and storage elastic modulus E ′ (unit: GPa) at a frequency of 10 Hz and 23 ° C. was measured.

<Production Example 1>
Bay pine wood flour (Miyashita Wood Co., Ltd./particle size 50 to 250 μm (average particle size 138 μm)) was prepared as a raw material. Next, the purification process of the cellulose was implemented in the process described below. A sodium carbonate aqueous solution adjusted to 2% by weight was added to the wood flour material, and the mixture was heated at a liquid temperature of 78 to 82 ° C. for 6 hours with constant stirring. After this treatment, the liquid was filtered off, and the remaining wood flour was washed with water and filtered off. Next, an aqueous solution adjusted to 0.27% by weight of acetic acid and 1.33% by weight of sodium chlorite was added to the remaining wood flour, and heated at a liquid temperature of 78 to 82 ° C. for 5 hours. After the treatment, the liquid was filtered off, and the remaining wood flour was washed with water and filtered off. Next, a sodium hydroxide aqueous solution adjusted to 5% by weight was added to the remaining wood flour, and left at room temperature to 30 ° C. for 16 hours. Finally, the remaining wood flour was washed with water and filtered to obtain cellulose. In addition, when carrying out this purification treatment, the cellulose was always wetted (water content 10% by weight or more) without completely drying the cellulose, including when it was filtered.

<Production Example 2>
Abaca fiber cut into 1 cm was prepared as a raw material, and purification treatment was performed in the same process as in Production Example 1.

<Example 1>
5 g of the water-containing cellulose obtained in Production Example 1 was weighed out as a solid content, and the water content was replaced with acetone. To this was added 150 ml of N, N-dimethylformamide, 18.2 ml of pyridine, and 17.5 ml of benzoyl chloride, and the mixture was stirred and reacted at room temperature for 1 hour. Thereafter, the reaction solution was filtered, washed with methanol, and further washed with a large amount of demineralized water until neutral.
The modification rate of the obtained benzoylated cellulose was 9 mol%. Moreover, the thermal decomposition temperature computed from TG-DTA was 337 degreeC.

  The obtained benzoylated cellulose is made into a 0.5% by weight aqueous suspension, and a gap between the gaps is obtained by using a stone mortar supermass colloider MKCA6-2 of Masuko Sangyo Co., Ltd. and a stone mortar of GC6-80. It was charged from the raw material charging port at a rotation speed of 1500 rpm at 80 μm. The treated cellulose dispersion that passed through this mill was again charged into the raw material inlet, and passed through the mill twice in total. Then, it was passed 10 times at 245 MPa through an ultra-high pressure homogenizer (Sugino Machine Ultimate).

  This cellulose dispersion was diluted with water to a concentration of 0.13% by weight, and 150 g was put into a 90 mm diameter vacuum filter (KG-90 Advantech) using a PTFE membrane filter (T100A090C Advantech) with a pore size of 1 μm. Filtration was started under reduced pressure conditions (−0.09 MPa). When the solid content of the material to be filtered on the filter reached about 5% by weight, 2-propanol was added and replaced. In this filtration treatment, the filtration time required to complete the filtration was 13 minutes. Then, it was press-dried at 120 ° C. and 0.14 MPa for 5 minutes to obtain a white modified cellulose sheet having a thickness of 66 μm.

The average fiber diameter of the modified cellulose fiber calculated from SEM observation on the surface of this modified cellulose sheet was 31 nm.
Further, from the wide-angle X-ray diffraction image, it was confirmed that the crystal structure was a cellulose I type crystal structure.

This modified cellulose sheet was mixed with 96 parts by weight of bis (methacryloyloxymethyl) tricyclo [5.2.1.0 ^2,6 ] decane, ⁶ parts by weight of pentaerythritol tetrakis (β-thiopropionate), 2,4,6. -Trimethylbenzoyldiphenylphosphine oxide (BASF's Lucillin TPO) 0.05 parts by weight and benzophenone 0.05 parts by weight were impregnated and left under reduced pressure overnight. This was sandwiched between two glass plates and irradiated using an electrodeless mercury lamp (“D bulb” manufactured by Fusion UV Systems) under an irradiance of 400 mW / cm ² at a line speed of 7 m / min. The irradiation dose at this time was 0.12 J / cm ² . This operation was performed twice by inverting the glass surface. The temperature of the glass surface after ultraviolet irradiation was 25 ° C.

Next, irradiation was performed under an irradiance of 1900 mW / cm ^{2 at} a line speed of 2 m / min. The irradiation dose at this time was 2.7 J / cm ² . This operation was performed 8 times by inverting the glass surface. The temperature of the glass surface after ultraviolet irradiation was 44 ° C. The irradiation dose was 21.8 J / cm ² . After completion of the ultraviolet irradiation, the glass plate was removed and heated in a vacuum oven at 190 ° C. for 4 hours to obtain a composite material. In addition, the irradiance of ultraviolet rays was measured at 23 ° C. by using an ultraviolet ray illuminance meter “UV-M02” manufactured by Oak Seisakusho and using an attachment “UV-35”.

<Example 2>
5 g of the water-containing cellulose obtained in Production Example 1 was taken as a solid, and the water was replaced with acetone. To this, 150 ml of N, N-dimethylformamide, 18.2 ml of pyridine and 17.6 g of 2-naphthoyl chloride were added and stirred, and reacted at room temperature for 1 hour. Thereafter, the reaction solution was filtered, washed with methanol, and further washed with a large amount of demineralized water until neutral.
The modification rate of the obtained naphthoylated cellulose was 5 mol%. Moreover, the thermal decomposition temperature computed from TG-DTA was 315 degreeC.

  The obtained naphthoylated cellulose was refined and formed into a sheet in the same manner as in Example 1. The filtration time required to form a sheet was 60 minutes. Moreover, the thickness of the obtained modified cellulose sheet was 70 micrometers.

  The average fiber diameter of the modified cellulose fiber calculated from SEM observation of the surface of this modified cellulose sheet was 22 nm.

  A cellulose composite material was obtained in the same manner as in Example 1 using the obtained modified cellulose sheet.

  The physical properties and characteristics of the modified cellulose fibers and cellulose composite materials in Examples 1 and 2 are shown in Table 1 together with the filtration time during the production of the cellulose sheet.

<Comparative Example 1>
The cellulose obtained in Production Example 1 was weighed out in a solid content of 5 g, and water was replaced with acetic acid. 250 ml of toluene, 200 ml of acetic acid, and 1 ml of a 60 wt% perchloric acid aqueous solution were mixed, and the cellulose was added thereto, and then 9 ml of acetic anhydride was added and reacted at room temperature for 1 hour with stirring. After the reaction, the reaction solution was filtered and washed with methanol and demineralized water in this order.
The modification rate of the obtained acetylated cellulose was 30 mol%. Moreover, the thermal decomposition temperature computed from TG-DTA was 348 degreeC.

  The obtained acetylated cellulose was made into a 0.5% by weight aqueous suspension, passed through a grinder under the same conditions as in Example 1, and then passed through an ultrahigh pressure homogenizer. The cellulose dispersion diluted with water was filtered in the same manner as in Example 1. At this time, the filtration time required to complete the filtration was 29 minutes. Thereafter, it was press-dried at 120 ° C. and 0.14 MPa for 5 minutes to obtain a white cellulose sheet.

The average fiber diameter of the modified cellulose fiber calculated from SEM observation of the surface of this cellulose sheet was 32 nm.
Further, from the wide-angle X-ray diffraction image, it was confirmed that the crystal structure was a cellulose I type crystal structure.

Using this cellulose sheet, a cellulose composite material was obtained in the same manner as in Example 1.
The physical properties and characteristics of the modified cellulose and the cellulose composite material in this comparative example are shown in Table 1 together with the filtration time during the production of the cellulose sheet.

<Comparative example 2>
The cellulose obtained in Production Example 1 was made into a 0.5% by weight aqueous suspension, charged into a high-speed rotary homogenizer, and subjected to defibration for 60 minutes at 20,000 rpm. This cellulose dispersion was diluted with water to a concentration of 0.13% by weight and filtered in the same manner as in Example 1. At this time, the filtration time required to complete the filtration was 150 minutes. Thereafter, it was press-dried at 120 ° C. and 0.14 MPa for 5 minutes to obtain a white cellulose sheet.

The average fiber diameter of the cellulose fiber calculated from SEM observation of the surface of this cellulose sheet was 26 nm.
Further, from the wide-angle X-ray diffraction image, it was confirmed that the crystal structure was a cellulose I type crystal structure.

Using this cellulose sheet, a cellulose composite material was obtained in the same manner as in Example 1.
The physical properties and characteristics of cellulose and cellulose composite material in this comparative example are shown in Table 1 together with the filtration time during the production of the cellulose sheet.

<Comparative Example 3>
The purified abaca obtained in Production Example 2 was chemically modified in the same manner as in Example 1 to obtain benzoylated cellulose. The modification rate of the obtained benzoylated cellulose was 9 mol%. Moreover, the thermal decomposition temperature computed from TG-DTA was 325 degreeC.

The obtained benzoylated cellulose was refined and made into a sheet in the same manner as in Example 1. The filtration time required to form a sheet was 5 minutes. Moreover, the thickness of the obtained modified cellulose sheet was 75 micrometers.
The average fiber diameter of the modified cellulose fiber calculated from SEM observation of the surface of this modified cellulose sheet was 104 nm.
A cellulose composite material was obtained in the same manner as in Example 1 using the obtained modified cellulose sheet.

<Comparative Example 4>
The refined abaca obtained in Production Example 2 was subjected to the same treatment as Comparative Example 3 except that the cellulose sheet was not chemically modified and a cellulose composite material was prepared using this cellulose sheet.
The filtration time required to form a sheet was 111 minutes. Moreover, the thickness of the obtained cellulose sheet was 62 μm.
The average fiber diameter of the modified cellulose fiber calculated from SEM observation of the surface of this cellulose sheet was 38 nm.

  The physical properties and characteristics of the cellulose fibers and cellulose composite materials in Comparative Examples 3 to 4 are shown in Table 1 together with the filtration time during the production of the cellulose sheet.

Table 1 shows the following: The modified cellulose fibers of the present invention obtained in Examples 1 and 2 have a higher thermal decomposition temperature and excellent heat resistance than the unmodified cellulose of Comparative Example 2. Further, when comparing the filtration time required to obtain a cellulose sheet from a cellulose aqueous dispersion having a similar fiber diameter, the benzoylated cellulose and naphthylated cellulose of Examples 1 and 2 modified with an aromatic ring-containing substituent are: The time required for filtration is significantly shorter than the unmodified cellulose of Comparative Example 2, and the benzoylated cellulose of Example 1 was modified with an aliphatic-containing substituent even though the modification rate was about one third. Even shorter than the acetylated cellulose of Comparative Example 1. From this, it can be said that the cellulose modified with an aromatic ring-containing substituent has high productivity. In the case of industrial filtration, the difference in filtration time is further increased because the pressure difference is smaller than the differential pressure shown in Examples 1 and 2, so the difference in filtration time between Example and Comparative Example is practical. It can be said that there is a very advantageous difference.
In addition, when looking at the physical properties of the cellulose composite material, as described above, the cellulose composite material using the modified cellulose fiber of the present invention has higher transparency, non-coloring property, low linear expansion coefficient, and high elastic modulus. Excellent in.

  In Comparative Examples 3 to 4, the raw material derived from hemp (Abaca) is used as the cellulose raw material instead of the woody cellulose raw material, but the benzoylated cellulose of Comparative Example 3 in which Abaca was modified with an aromatic ring-containing substituent was Compared with the benzoylated cellulose of Example 1, the fiber diameter is large and it is difficult to make fine. Therefore, even if the benzoylated cellulose sheet of Comparative Example 3 is combined with a polymer material, a highly transparent and low linear expansion coefficient composite material cannot be obtained.

The cellulose composite material of the present invention using the modified cellulose fiber of the present invention is highly transparent and excellent in high strength, low water absorption, low coloration and optical properties, so that it is a liquid crystal display, plasma display, organic EL display, field emission. It is suitable as a display, a substrate or a panel of a display, a rear projection television or the like. Moreover, it is suitable for substrates for solar cells such as silicon-based solar cells and dye-sensitized solar cells. The substrate may be laminated with a barrier film, ITO, TFT, or the like. Further, it is suitably used for window materials for automobiles, window materials for railway vehicles, window materials for houses, window materials for offices and factories, and the like. As the window material, a film such as a fluorine film or a hard coat film or a material having impact resistance or light resistance may be laminated as necessary.
Further, it can be used as a structure other than the transparent material utilizing the characteristics such as low linear expansion coefficient, high elasticity, and high strength. In particular, it is suitably used as automotive materials such as interior materials, outer plates, bumpers, etc., personal computer casings, home appliance parts, packaging materials, building materials, civil engineering materials, marine products, and other industrial materials.

Claims (8)

A method for producing a dispersion of a modified cellulose fiber having an average fiber diameter of 100 nm or less and having a cellulose type I crystal structure modified with an aromatic ring-containing substituent,
(1) A process of obtaining modified cellulose by modifying cellulose before defibration obtained from wood with an aromatic ring-containing substituent
(2) A method for producing a modified cellulose fiber dispersion, comprising sequentially performing a step of defibrating the modified cellulose obtained in (1) to an average fiber diameter of 100 nm or less to obtain a modified cellulose fiber dispersion.   The method for producing a modified cellulose fiber dispersion according to claim 1, wherein the aromatic ring-containing substituent is an aromatic ring-containing ester group.   The method for producing a modified cellulose fiber dispersion according to claim 1 or 2, wherein the modification rate of cellulose with respect to all hydroxyl groups is 9 mol% or less.   A method for producing a modified cellulose fiber sheet, comprising a step of papermaking the modified cellulose fiber dispersion obtained by the method according to claim 1.   A cellulose fiber contained in the modified cellulose fiber dispersion obtained by the method according to any one of claims 1 to 3, or a modified cellulose fiber sheet obtained by the method according to claim 4, and a polymer other than cellulose. A method for producing a cellulose composite material, comprising a step of compositing.   A modified cellulose fiber dispersion obtained by the method according to claim 1.   A modified cellulose fiber sheet obtained by the method according to claim 4.   A cellulose composite material obtained by the method according to claim 5.