JP4548415B2 - UV curable composition - Google Patents

Description

The present invention relates to a cationically curable ultraviolet curable composition suitable as a liquid crystal display, a plasma display, a display such as a touch panel, and an optical material such as an optical lens that requires transparency.
Furthermore, the present invention relates to a novel biphenyl derivative having an oxetane ring capable of cationic polymerization and a method for producing the same.

  The ultraviolet curable composition is widely used as an optical material because it has excellent productivity and can easily give a cured product having a fine shape. For example, a lens sheet for a liquid crystal display is prepared by pouring an ultraviolet curable composition into a mold having a fine concavo-convex shape, covering a transparent plastic base material from above, and irradiating it with ultraviolet light to cure the plastic base material. By releasing the mold resin together, a lens sheet to which the shape of the mold is transferred is formed. Further, the ultraviolet curable composition is also used as a binder for diffusion sheets and as a bonding material for various films.

  Most of the raw materials of the ultraviolet curable composition are acrylic compounds, and the acrylic compounds occupy most of the optical applications as described above. However, in recent years, optical members having various configurations and methods for producing the same have been devised using ultraviolet curable compositions, and accordingly, strict performance is required for ultraviolet curable compositions. For example, UV curable compositions are required to have good adhesion to substrates that are difficult to adhere with conventional acrylic compounds, low shrinkage when cured, and low water absorption. . And the cation curable composition by an epoxy compound or an oxetane compound has the performance better than an acrylic compound at the point of these physical properties. However, it is difficult for these cationic curable ultraviolet curable compositions to reduce yellowing during curing as compared with acrylic compounds. For this reason, it has been difficult to apply a cationically curable ultraviolet curable composition to optical uses such as displays that require strict transparency.

  Oxetane compounds are recently attracting attention as monomers that can be cured by cationic polymerization or the like, and many oxetane compounds have been reported. For example, a bisoxetane ether compound obtained by contacting 3-alkyl-3-hydroxymethyloxetane and α, ω-dibromoalkane in the presence of an aqueous alkali metal hydroxide solution and a phase transfer catalyst has been reported (for example, For example, see Non-Patent Document 1, Non-Patent Document 2, Non-Patent Document 3, and Patent Document 1.) In addition, a bisoxetane ether compound obtained by contacting 3-alkyl-3-halomethyloxetane with an alkali metal phenolate of a dihydric phenol has been reported (for example, see Patent Document 2).

Various bisoxetane ether compounds have been reported (see, for example, Patent Document 3, Patent Document 4, Patent Document 5, Patent Document 6, and Patent Document 7).
Moreover, the oxetane compound represented by Formula (a) has been reported (for example, refer patent document 8).

In formula (a), R _{1 to} R ₄ represent a hydrogen atom or a methyl group, and R ₅ and R ₆ represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

  However, none of these known documents describes or suggests a biphenyl derivative having one osetan ring in one molecule.

Examples of the cationically curable composition include an epoxy compound and / or a cationic polymerizable compound that is an oxetane compound, an aromatic ether compound such as phenylene and naphthalene having a glycidyl group or a 3-ethyl-3-oxetanylmethyl group as an ether bond, In addition, a photocationic curable composition containing a photocationic initiator has been reported (see, for example, Patent Document 9).
Also reported is a UV curable composition for transmission screens characterized in that it contains a bisphenol-type epoxy (meth) acrylate and / or urethane (meth) acrylate, a vinyl ether compound, a cationic photopolymerization initiator and a radical photopolymerization initiator. (For example, see Patent Document 10). Moreover, it is obtained by reacting 5 to 60% of the hydroxyl group in the polymerizable compound and / or phenoxy resin with 5 to 95% of the epoxy group in the epoxy compound and / or α, β-unsaturated monoisocyanate. A curable composition used for a Fresnel lens or the like containing a polymerizable compound and a radical photopolymerization initiator and / or a cationic photopolymerization initiator has been reported (for example, see Patent Document 11).

JP-A-6-16804 German Patent No. 1021858 JP-A-7-53711 JP 7-173279 A Japanese Patent Laid-Open No. 8-245578 JP-A-9-309950 JP-A-10-212343 JP 2001-31665 A JP 2003-096184 A JP 07-199359 A JP 2001-163939 A Bull. Chem. Soc. Jpn. , 61, pp. 1653 (1989) Pure Appl. Chem. , A29 (10), pp. 915 (1992) Pure Appl. Chem. , A30 (2 & 3), pp. 189 (1993)

The problem to be solved by the present invention is to provide a resin with little yellowing that can be used in optical applications where strict colorless transparency is required, and a cationically curable ultraviolet curable composition that gives this resin And a method of manufacturing the same.
Still another object of the present invention is to provide a novel biphenyl derivative capable of cationic polymerization and having one oxetane ring in one molecule and a method for producing the same. Furthermore, it is to provide a composition containing the novel biphenyl derivative and a cured product thereof.

As a result of intensive studies to solve the above problems, the present inventors have found that the above problems can be solved by the following means (1), and have completed the present invention. It describes below with (2)-(7) which is a preferable embodiment.
(1) an ultraviolet curable composition comprising at least one compound represented by the following formula (4) , a compound A having two or more cationically polymerizable groups, and a photocationic polymerization initiator,

(In Formula (4) , R ¹ represents a hydrogen atom or a methyl group, R ² represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, n represents an integer of 0 to 20, and B represents a carbon number. 1 to 6 alkyl groups, C 1 to C 6 alkoxy groups or halogen atoms, B substituent number L represents an integer from 0 to 5, and B substituent number m is an integer from 0 to 4 Represents .)

(2) The ultraviolet curable composition according to (1), further comprising Compound B having one cationically polymerizable group,
(3) The ultraviolet curable composition according to (1) or (2), wherein the cationic photopolymerization initiator is a sulfonium salt,
(4) A cured product obtained by irradiating the composition according to (1) or (2) with ultraviolet rays,
(5) A cured product obtained by irradiating the composition according to (3) with ultraviolet rays,
(6) The cured product according to (4), wherein the cured product is an optical material,
(7) The cured product according to (5), wherein the cured product is an optical material.

Furthermore, it discovered that the said subject could be solved by the following means (8) and (10). It is described below together with (9) which is a preferred embodiment.
(8) a compound represented by the following formula (4),

(In Formula (4), R ¹ represents a hydrogen atom or a methyl group, R ² represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, n represents an integer of 0 to 20, and B represents a carbon number. 1 to 6 alkyl groups, C 1 to C 6 alkoxy groups or halogen atoms, B substituent number L represents an integer from 0 to 5, and B substituent number m is an integer from 0 to 4 Represents.)

(9) A cationic curable composition containing the compound represented by formula (4) according to (8) and a cationic polymerization initiator,
(10) A process for producing a compound represented by the formula (4) , comprising reacting a compound represented by the formula (5) with a compound represented by the formula (6) in the presence of an alkali. is there.

In Formula (5), R ¹ represents a hydrogen atom or a methyl group, n represents an integer of 0 to 20, B represents an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or a halogen atom The number of substituents L of B represents an integer from 0 to 5, and the number of substituents m of B represents an integer from 0 to 4.

In the formula (6), R ² represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

  Since the cationic curable ultraviolet curable composition of the present invention has very little yellowing after curing, it requires transparency for display materials such as liquid crystal displays, plasma displays, touch panels, and optical lenses. It can be suitably used as an optical material. The compound represented by Formula (4) can be suitably used as a raw material for a cured product that requires transparency.

The ultraviolet-visible absorption spectrum of the glass slide and polyethylene terephthalate (PET) film which were used in the Example and the comparative example is shown. The ultraviolet-visible absorption spectrum in evaluation (the 1) of transparency of hardened | cured material is shown. The ultraviolet visible absorption spectrum in evaluation (the 2) of transparency of hardened | cured material is shown. The ultraviolet visible absorption spectrum in evaluation (the 2) of transparency of hardened | cured material is shown.

Explanation of symbols

1-4 horizontal axis: wavelength (nm), vertical axis of FIGS. 1-4: transmittance (%)
Solid line in FIG. 1: slide glass Broken line in FIG. 1: PET film Thick solid line in FIG. 2: transmittance of the composition of Example 3 sandwiched between the glass slides and cured The broken line in FIG. 2: the composition of Example 4 Transmittance of a material cured by being sandwiched between glass slides One-dot broken line in FIG. 2: Permeability of a material cured by sandwiching the composition of Example 5 between slide glasses Thin solid line in FIG. 2: Slide the composition of Comparative Example 1 Transmittance of cured product sandwiched between glass: thick solid line in FIG. 3: Transmittance of cured composition of Example 3 on PMMA Thin solid line of FIG. 3: cured composition of Comparative Example 2 on PMMA Transmission line of FIG. 3: Transmission of the composition of Comparative Example 3 cured on PMMA Thick solid line of FIG. 4: Transmission of the composition of Example 3 cured on PMMA Thin solid line: Transmittance of the composition of Comparative Example 4 cured on PMMA Broken line in FIG. 4: Transmittance of the composition of Comparative Example 5 cured on PMMA

Hereinafter, the present invention will be described in detail.
The ultraviolet curable composition of the present invention comprises at least one compound represented by the following formula (4) , compound A having two or more cationically polymerizable groups, and a photocationic polymerization initiator. The ultraviolet curable composition of the present invention forms a cationically polymerizable resin.

(In Formula (4) , R ¹ represents a hydrogen atom or a methyl group, R ² represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, n represents an integer of 0 to 20, and B represents a carbon number. 1 to 6 alkyl groups, C 1 to C 6 alkoxy groups or halogen atoms, B substituent number L represents an integer from 0 to 5, and B substituent number m is an integer from 0 to 4 Represents .)

Moreover, the compound of this invention is a compound represented by said Formula (4) , and the said compound can be used suitably for cationic polymerization.

○ Although equation n of the compound represented by formula (4) (4) represents an integer of 0 to 20, preferably from 0 to 5, particularly preferably 0. It is preferable that n is 20 or less because the concentration of the biphenyl skeleton is high and the effect of reducing yellowing of the cured product is high. In particular, when n in the formula (4) is 0, not only the effect of reducing yellowing is high, but also the raw material is cheaper than those having n = 1 or more, and the introduction of the oxetani group is facilitated. From this point, it is particularly preferable.

B in the above formula (4) represents a monovalent substituent at an arbitrary position on the aromatic ring, the number of substituents L of B represents an integer of 0 to 5, and the number of substituents m of B is 0 to 4. Represents an integer.
B preferably represents an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or a halogen atom, as long as it does not inhibit the cationic polymerizability of the compound represented by formula (4). Of monovalent substituents can be selected. The alkyl group and the alkoxy group may have a branch. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
Among these, a methyl group, a methoxy group, a fluorine atom, and a bromine atom are preferable, and a methyl group is particularly preferable.
When m and L are 0, it represents that there is no B on the aromatic ring, and when m is 1 to 4, it represents that 1 to 4 Bs are bonded on the aromatic ring. In the case of 1-5, it represents that 1-5 each of B is bonded on the aromatic ring. The L B and m B substituted on the aromatic ring may be the same or different, and can be independently selected.
L and m in the formula (4) are preferably 0 or 2. When L and m in the formula (4) are 2, those bonded to the 3, 5, 3 ′, 5 ′ positions are preferable.

The bonding position of the compound having an oxetanyl group in the above formula (4) of the present invention is the 2-position, 3-position or 4-position, preferably 2-position or 4-position.

The compound represented by formula (4) can be obtained by the oxetane compound represented by the formula compounds represented by the formula (5) (6) are reacted in the presence of an alkali. If necessary in this reaction, a solvent may be used. Further, a phase transfer catalyst may be used.

In Formula (5), R ¹ represents a hydrogen atom or a methyl group, n represents an integer of 0 to 20, B represents an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or a halogen atom The number of substituents L of B represents an integer from 0 to 5, and the number of substituents m of B represents an integer from 0 to 4.

In the formula (6), R ² represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

In the compound represented by the formula (4) , those in which n is other than 0 are obtained by adding ethylene oxide or propylene oxide to 2-phenylphenol, 3-phenylphenol or 4-phenylphenol and their nuclear substitutes It can be synthesized from (a compound represented by the formula (5)). In addition, about the number of n of the compound represented by Formula (4) , it can control by controlling the quantity of the ethylene oxide or propylene oxide to add.
Moreover, the substituent B can be introduce | transduced into a phenyl nucleus of the raw material phenylphenol by a well-known method, for example, a methyl group etc. can be introduce | transduced by Friedel-Crafts reaction.
In addition, when the compound represented by Formula (4) is a single compound, n is an integer, but when it is a mixture of different numbers of n, n may be represented by a number having a decimal point. is there. In this case, n represents the average value of the mixture of the compounds represented by formula (4) with different numbers of n.

  Examples of the oxetane compound represented by the formula (6) used in the present invention include 3-alkyl-3-chloromethyloxetane and 3-chloromethyloxetane. Examples of the 3-alkyl-3-chloromethyloxetane include 3-chloromethyl-3-methyloxetane, 3-chloromethyl-3-ethyloxetane, and 3-chloromethyl-3-propyloxetane. In the present invention, 3-alkyl-3-chloromethyloxetane is preferable, and 3-chloromethyl-3-methyloxetane or 3-chloromethyl-3-ethyloxetane is more preferable.

In the present invention, the alkali used when synthesizing the compound represented by the formula (4) from the compound represented by the formula (5) and the compound represented by the formula (6 ) is an alkali metal or an alkali metal water. Examples thereof include oxides, alkali metal carbonates, alkaline earth metal hydroxides, alkaline earth metal carbonates and alkali metal hydrides, preferably alkali metals, alkali metal hydroxides, or alkali metals. Hydride. A plurality of alkalis may be used in combination. Specific examples of the alkali used in this synthesis are sodium hydroxide, potassium hydroxide, lithium hydroxide, calcium hydroxide, sodium carbonate, potassium carbonate, sodium hydride, potassium hydride, metallic sodium, metallic potassium and the like. . Among these, sodium hydroxide and potassium hydroxide are preferable because a sufficient conversion rate can be obtained in a short time.

As for the usage-amount of the said alkali, 1 mol or more is preferable with respect to the compound represented by 1 mol of Formula (5), It is still more preferable to use 1-8 mol, Most preferably, it is 1-2 mol. In consideration of the post-treatment, the alkali can be used in an amount of less than 1 mol with respect to 1 mol of the compound represented by the formula (5). When used as an alkali aqueous solution or water suspension, the alkali concentration is preferably 1 to 96% by weight, more preferably 20 to 96% by weight.
As the alkali metal hydroxide, a 5 to 60% by weight aqueous solution or powdered sodium hydroxide or potassium hydroxide is preferably used, and a 40 to 50% by weight aqueous solution is more preferably used.

As a solvent for use in the synthesis of the compound represented by the formula (4) , a solvent inert to the raw materials and reaction products can be used. This solvent is preferably a solvent that azeotropes with the water generated in the system at the time of synthesis. Examples of the solvent include benzene, toluene, xylene, ethylbenzene, methylcyclohexane, ethylcyclohexane, n-butyl ether and the like. The reaction time can be shortened by distilling the water produced in the synthesis system together with the solvent.
The amount of the solvent is preferably 0.05 to 100 parts by weight, more preferably 0.1 to 20 parts by weight with respect to 1 part by weight in total of the raw materials and reaction products in the reactor. It is preferable for the amount of the solvent to be in the above range because the yield per unit volume is high, the energy required for recovering the solvent is small, and it is economical. For the synthesis of the compound represented by the formula (4) , toluene, xylene, methylcyclohexane, ethylcyclohexane and the like are suitably used.

As the phase transfer catalyst that can be used in the synthesis of the compound represented by the formula (4) , a known phase transfer catalyst (for example, WP Weber, GW Gokel co-authored by Iwao Tabushi and Takako Nishitani) Any of “phase transfer catalysts” and those described in “Chemical Doujinshi Co., Ltd.” can be used. Of these, organic quaternary ammonium salts and phosphonium salts are preferred because of their high ability as a catalyst. Specific examples include tetra-n-butylammonium bromide, benzyltriethylammonium bromide, trioctylmethylammonium chloride, tetra-n-butylphosphonium chloride, trioctylethylphosphonium bromide and tetraphenylphosphonium chloride.

The reaction temperature when synthesizing the compound represented by the formula (4) is preferably 80 to 150 ° C, particularly preferably 100 to 120 ° C. The reaction time when synthesizing the compound represented by the formula (4) is preferably 4 to 50 hours, although it depends on the reaction temperature and the presence or absence of the use of a phase transfer catalyst.

After the completion of the reaction, the target compound (target product) represented by the formula (4) can be obtained by washing the reaction solution cooled to room temperature with water, distillation and the like. The target product can be confirmed by ¹ H-NMR and ¹³ C-NMR spectra.

R ^{2 in} Formula (4) represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and the alkyl group may have a branch. R ² is preferably a methyl group or an ethyl group.

The composition of the present invention, but contains at least one compound represented by formula (4), the R ^1, R ² Contact and substituent B type and, L, m, n number different of be used compounds are mixed have good.

In addition, when the compound represented by the formula (4) is L = m = n = 0 and the binding position of the compound having an oxetanyl group is the 4th position, the compound is solid at room temperature. On the other hand, when the bonding position is at the 2nd position, the compound is liquid at room temperature, so the composition is liquid even if the number of blending parts is increased. Therefore, the binding position of the compound having an oxetanyl group is preferably the 2-position.
Furthermore, even if it has a substituent B, the binding site of the compound having an oxetanyl group is preferably the 2-position.

In the composition of the present invention, the total amount of the compound represented by the formula (4) is not particularly limited, but the cationic polymerizable component is preferably 100 parts by weight, preferably 10 to 99 parts by weight, more preferably Is 20 to 90 parts by weight, particularly preferably 30 to 80 parts by weight. It is preferable for the number of blended parts to be in the above range since the effect of reducing yellowing of the cured product is high.
The cationic polymerizable component includes the compound represented by the formula (4) , the compound A having two or more cationic polymerizable groups, the compound B having one cationic polymerizable group, and the like. Examples of the cationic polymerizable group include an epoxy group, an oxetane group, and a vinyl ether group.
Moreover, the compound represented by Formula (4) can also be used for the use for which transparency of hardened | cured material is not requested | required.

The cationic polymerization initiator in the present invention is activated by the application of light or heat to generate an acid component, and acts to induce cationic polymerization of a cationic polymerizable group in the composition.
As the cationic polymerization initiator, any photocationic polymerization initiator that is activated by irradiation with light and can induce polymerization of a cationic polymerizable group is preferably used. A photosensitizer can also be used in combination. Furthermore, as the cationic polymerization initiator, any thermal cationic polymerization initiator can be used as long as it is activated by heating and can induce polymerization of the cationic polymerizable group.

The photocationic polymerization initiator in the present invention is a compound that generates an acid that can be cationically polymerized by irradiation with ultraviolet rays. Examples of the photocationic polymerization initiator include onium salts and organometallic complexes.
Examples of organometallic complexes include iron-allene complexes, titanocene complexes, and arylsilanol-aluminum complexes.
Specific examples of onium salts include diazonium salts, iodonium salts, sulfonium salts, selenium salts, pyridinium salts, ferrocenium salts, phosphonium salts, and thiopyrinium salts. In the present invention, when an iodonium salt is used, it may be colored yellow, and therefore, a sulfonium salt such as an aromatic sulfonium salt or a dialkylphenacylsulfonium salt is preferable, and more preferably, in terms of curability and low yellowing. Aromatic sulfonium salts, particularly preferably triarylsulfonium salts.

When an onium salt photocationic polymerization initiator such as an iodonium salt or a sulfonium salt is used in the composition of the present invention, BF ₄ ⁻ , AsF ₆ ⁻ , SbF ₆ ⁻ , PF ₆ ⁻ , and B (C ₆ F _{5) 4} ^- but like, preferably SbF ₆ ^- and the like ^- and PF _6.

  Examples of commercially available triarylsulfonium salts include Syracure UVI-6990, UVI-6922, and UVI-6974 manufactured by Dow Chemical Japan Co., Ltd., and Adekaoptomer SP-150 manufactured by Asahi Denka Kogyo Co., Ltd. Examples include SP-152, SP-170, and SP-172, and WPAG-593, WPAG-596, WPAG-640, and WPAG-641 manufactured by Wako Pure Chemical Industries, Ltd., which can be used in the present invention.

  Commercially available aromatic iodonium salts include GE Toshiba Silicone UV-9380C, Rhodia PHOTOINITIATOR 2074, Wako Pure Chemical Industries, Ltd. WPI-116, WPI-113 and CD-1012 (trade name, manufactured by Sartomer) Etc.

  Among these, UVI-6990 and UVI-6922 are particularly preferable in terms of curability and low yellowing.

  The compounding quantity of the photocationic polymerization initiator in this invention can be suitably adjusted according to the kind and irradiation amount of an ultraviolet-ray. For example, the amount is preferably 0.01 to 5 parts by weight, more preferably 0.1 to 5 parts by weight, and particularly preferably 1 to 3 parts with respect to 100 parts by weight of the cationic polymerizable component. It is preferable that the amount of the cationic photopolymerization initiator is within the above range because sufficient curability can be obtained, and heat resistance and low water absorption after polymerization are sufficient. In addition, the amount of components that are truly necessary for curing is not decreased, and other properties such as a decrease in physical properties of the cured product, yellowing of the cured product, and heat resistance are not decreased.

A sensitizer can be used in combination with the composition of the present invention in order to increase the activity of the photocationic polymerization initiator. As a sensitizer that can be used in the present invention, it is possible to use a compound disclosed by Crivello in Advanced in Polymer Science (Adv. In Polymer Sci., 62, 1 (1984)). Specific examples include pyrene, perylene, acridine orange, thioxanthone, 2-chlorothioxanthone, and benzoflavine.
In addition, compounds widely used as photo radical polymerization initiators can also be used. Particularly, when a compound having a radical polymerizable group in the molecule is blended in the composition of the present invention, the radical polymerization initiator is used. Can also be added. Examples of the radical polymerization initiator include compounds that generate radicals by heat, light, redox reaction, or the like. As such a thing, an organic peroxide, an azo compound, a redox initiator, etc. are mentioned. Specifically, thioxanthones such as benzophenone, 2,4-diethylthioxanthone, 2-isopropylthioxanthone, and 2,4-dichlorothioxanthone, benzoin ethers such as benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether, 2,2 -Benzyldimethylketals such as dimethoxy-1,2-diphenylethane-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1- (4-isopropylphenyl) -2-hydroxy- Examples include α-hydroxyalkylphenones such as 2-methylpropan-1-one and 1-hydroxycyclohexyl phenyl ketone, and α-dicarbonyl compounds such as camphorquinone.

  However, in the composition of the present invention, it is preferable to use a sulfonium salt as a photocationic polymerization initiator and no sensitizer because the yellowing of the cured product can be reduced.

  In the composition of the present invention, the wavelength range of ultraviolet rays used for curing the composition is not particularly limited, but is preferably 200 to 380 nm in consideration of both curability and low yellowing. When considering only the little yellowing, the thickness is preferably 300 to 380 nm, particularly preferably 320 to 380 nm.

Further, the light source that can be used when polymerization is carried out by active energy rays is not particularly limited, but has a light emission distribution at a wavelength of 400 nm or less, for example, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure Mercury lamps, chemical lamps, black light lamps, microwave-excited mercury lamps, metal halide lamps, and the like can be used. The light irradiation intensity to the composition is controlled for each target product and is not particularly limited, but is a light wavelength region effective for activating a cationic polymerization initiator having photolatency ( The light irradiation intensity of (depending on the polymerization initiator) is preferably 0.1 to 100 mW / cm ² . It is preferable that the light irradiation intensity to the composition is within the above range since the reaction time is appropriate. Moreover, it is preferable because the heat radiated from the lamp and the heat generated during the polymerization of the composition do not cause a decrease in cohesion of the obtained cured product, yellowing or deterioration of the support. The light irradiation time to the composition is controlled for each target product and is not particularly limited, but is expressed as a product of the light irradiation intensity and the light irradiation time in the light wavelength region. It is preferable that the integrated light amount is set to be 10 to 5,000 mJ / cm ² . It is preferable that the integrated light amount of the composition is within the above range because active species are sufficiently generated from the initiator and the properties of the resulting cured product are not deteriorated. In addition, the irradiation time is short and productivity is improved, which is preferable. In addition, most compositions are dry to the touch by cationic polymerization after 0.1 to several minutes after irradiation with active energy rays, but it is also preferable in some cases to use heating together to promote the reaction of cationic polymerization. .

The compound A having two or more cationically polymerizable groups to be blended in the composition of the present invention preferably has a cationically polymerizable group of 10 or less, more preferably 5 or less. Examples of the compound A having two or more cationically polymerizable groups include a compound A having an epoxy group, a compound A having an oxetanyl group, and a compound A having a vinyl ether group, and a mixture thereof can be used. it can. As the compound A having two or more cationically polymerizable groups, a bifunctional glycidyl ether type epoxy compound is preferable when importance is attached to the adhesion, and a bifunctional or higher alicyclic type when importance is attached to the curability. Epoxy compounds and / or oxetane compounds are preferred. Moreover, when improving the elasticity modulus above glass transition temperature, trifunctional or more is preferable.
Compound A is preferably contained in an amount of 1 to 80 parts by weight, more preferably 5 to 60 parts by weight, based on 100 parts by weight of the compound component containing a cationically polymerizable group in the composition of the present invention. 10 to 50 parts by weight is more preferable.

  Examples of the compound A having an epoxy group include dicyclopentadiene dioxide, limonene dioxide, 4-vinylcyclohexene dioxide, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, and di (3,4-epoxy). (Cyclohexyl) adipate, bisphenol A type epoxy resin (bisphenol A diglycidyl ether), halogenated bisphenol A type epoxy resin, hydrogenated bisphenol A type epoxy resin, bisphenol S diglycidyl ether, halogenated bisphenol S diglycidyl ether, hydrogenated bisphenol S diglycidyl ether, bisphenol F type epoxy resin, halogenated bisphenol F type epoxy resin, hydrogenated bisphenol F type epoxy resin, 1 6-hexanediol diglycidyl ether, polytetramethylene glycol diglycidyl ether, compounds in which both ends of polybutadiene are glycidyl etherified, epoxy such as o-, m-, p-cresol novolac type epoxy resin and phenol novolac type epoxy resin Novolak resin, trimethylolpropane triglycidyl ether, pentaerythritol tetraglycidyl ether, 3,4-epoxycyclohexylmethyl-3 ′, 4′-epoxycyclohexanecarboxylate, 2- (3,4-epoxycyclohexyl-5,5-spiro -3,4-epoxy) cyclohexane-meta-dioxane, bis (3,4-epoxycyclohexylmethyl) adipate, bis (3,4-epoxy-6-methylcyclohexylmethyl) Adipate, 3,4-epoxy-6-methylcyclohexyl-3 ′, 4′-epoxy-6′-methylcyclohexanecarboxylate, methylenebis (3,4-epoxycyclohexane), dicyclopentadiene diepoxide, diethylene glycol ( 3,4-epoxycyclohexylmethyl) ether, ethylenebis (3,4-epoxycyclohexanecarboxylate), 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin triglycidyl ether, polyethylene glycol Diglycidyl ether, polypropylene glycol diglycidyl ethers; one or two or more kinds of aliphatic polyhydric alcohols such as ethylene glycol, propylene glycol and glycerin Polyglycidyl ethers of polyether polyols obtained by adding xylene oxide; diglycidyl esters of aliphatic long-chain dibasic acids; internal epoxidized products of polybutadiene, partially double bonds of styrene-butadiene copolymer are epoxy Compound (for example, Epofriend manufactured by Daicel Chemical Industries, Ltd.), a compound obtained by epoxidizing a part of polyisoprene of a block copolymer of ethylene-butylene copolymer and polyisoprene (for example, L-207 manufactured by KRATON) , Compounds having a structure in which a vinyl group of a 4-vinylcyclohexene oxide ring-opening polymer is epoxidized (for example, EHPE3150 manufactured by Daicel Chemical Industries, Ltd.), epoxidized vegetable oil (epoxidized soybean oil, epoxidized linseed oil, etc.), etc. Can be illustrated.

As the compound A having an oxetanyl group (the name in parentheses is the trade name or the developed product name, manufactured by Toagosei Co., Ltd.), 1,4-bis {[(3-ethyl-3-oxetanyl) methoxy] methyl} benzene (Aronoxetane OXT-121 (XDO)), di [2- (3-oxetanyl) butyl] ether (Aron oxetane OXT-221 (DOX)), 1,4-bis [(3-ethyloxetane-3-yl) methoxy] benzene (HQOX) 1,3-bis [(3-ethyloxetane-3-yl) methoxy] benzene (RSOX), 1,2-bis [(3-ethyloxetane-3-yl) methoxy] benzene (CTOX), 4,4 '-Bis [(3-ethyloxetane-3-yl) methoxy] biphenyl (4,4'-BPOX), 2,2'-bis [(3-ethyl-3-oxe Nyl) methoxy] biphenyl (2,2′-BPOX), 3,3 ′, 5,5′-tetramethyl [4,4′-bis (3-ethyloxetane-3-yl) methoxy] biphenyl (TM-BPOX) ), 2,7-bis [(3-ethyloxetane-3-yl) methoxy] naphthalene (2,7-NpDOX), 1,6-bis [(3-ethyloxetane-3-yl) methoxy] -2, 2,3,3,4,4,5,5-octafluorohexane (OFH-DOX), 3 (4), 8 (9) -bis [(1-ethyl-3-oxetanyl) methoxymethyl] -tricyclo [ 5.2.1.0 ^2.6 ] decane, 1,2-bis {2-[(1-ethyl-3-oxetanyl) methoxy] ethylthio} ethane, 4,4′-
Bis [(1-ethyl-3-oxetanyl) methyl] thiodibenzenethioether, 2,3-bis [(3-ethyloxetan-3-yl) methoxymethyl] norbornane (NDMOX), 2-ethyl-2-[( 3-ethyloxetane-3-yl) methoxymethyl] -1,3-O-bis [(1-ethyl-3-oxetanyl) methyl] -propane-1,3-diol (TMPTOX), 2,2-dimethyl- 1,3-O-bis [(3-ethyloxetane-3-yl) methyl] -propane-1,3-diol (NPGOX), 2-butyl-2-ethyl-1,3-O-bis [(3 -Ethyloxetane-3-yl) methyl] -propane-1,3-diol, 1,4-O-bis [(3-ethyloxetane-3-yl) methyl] -butane-1,4-diol, 2 4,6-O-tris [(3-ethyloxetane-3-yl) methyl] cyanuric acid, etherified product (BisAOX) of bisphenol A and 3-ethyl-3-chloromethyloxetane (abbreviated OXC), bisphenol F and Etherified product of OXC (BisFOX), etherified product of phenol novolac and OXC (PNOX), etherified product of cresol novolak and OXC (CNOX), oxetanylsilsesquioxane (OX-SQ), 3-ethyl-3-hydroxymethyloxetane Examples thereof include silicon alkoxide (OX-SC).
Further, various oxetane compounds described in JP-A-8-85775 and JP-A-8-134405 are exemplified, and among these, compounds having two or more oxetanyl groups can be used.

  Examples of the compound A having a vinyl ether group include cyclohexane dimethanol divinyl ether, triethylene glycol divinyl ether, and novolak divinyl ether.

Examples of the compound B to be blended in the composition of the present invention include a compound B having an epoxy group, a compound B having an oxetanyl group, and a compound B having a vinyl ether group, and a mixture thereof can also be used.
Compound B is preferably contained in an amount of 5 to 60 parts by weight, more preferably 10 to 50 parts by weight, based on 100 parts by weight of the compound component containing a cationically polymerizable group in the composition of the present invention. .

  As the compound B having an epoxy group, α-olefin epoxide such as vinylcyclohexene oxide, 4-vinylepoxycyclohexane, 1,2-epoxyhexadecane, phenyl glycidyl ether, 2-ethylhexyl glycidyl ether, dodecyl glycidyl ether, glycidyl methacrylate, epoxy Dioctyl hexahydrophthalate, di-2-ethylhexyl epoxyhexahydrophthalate, monoglycidyl ethers of higher aliphatic alcohols; phenol, cresol, butylphenol or monoglycidyl ether of polyether alcohol obtained by adding alkylene oxide to these And monoglycidyl esters of higher fatty acids.

  As compound B having an oxetanyl group (in parentheses are trade names or developed product names, manufactured by Toagosei Co., Ltd.), 3-ethyl-3- (2-ethylhexyloxymethyl) oxetane (Aron oxetane OXT-212 (EHOX)), 3 -Ethyl-3- (hexyloxymethyl) oxetane, 3-ethyl-3- (cyclohexyloxymethyl) oxetane (CHOX), 3-ethyl-3- (dodecyloxymethyl) oxetane (OXR-12), 3-ethyl -3- (octadecyloxymethyl) oxetane (OXR-18), 3-ethyl-3- (phenoxymethyl) oxetane (Aron oxetane OXT-211 (POX)), 3-ethyl-3-hydroxymethyloxetane (OXA) And 3-ethyl-3- (chloromethyl) oxetane.

  Examples of the compound B having a vinyl ether group include hydroxyethyl vinyl ether, hydroxybutyl vinyl ether, dodecyl vinyl ether, propenyl ether propylene carbonate, and cyclohexyl vinyl ether.

  Of these, compounds having an oxetanyl group are excellent in curability and can be preferably blended in the composition of the present invention. In particular, when a monofunctional compound having an oxetanyl group, that is, a compound having one oxetanyl group in one molecule is used, the cured product of the present invention is excellent even for a substrate having difficult adhesion. In order to show adhesiveness, it can apply preferably in such a use. Among them, particularly preferable is 3-ethyl-3- (phenoxymethyl) oxetane (Aron oxetane OXT-211 (POX)).

  In the cation curable composition of the present invention, a compound having at least one radical polymerizable group in the molecule can be blended as a polysynthetic component. Such as (meth) acrylate, (meth) acrylic acid, (meth) acrylamide, N-methylol (meth) acrylamide, N-methoxymethyl (meth) acrylamide and N-methoxybutyl (meth) acrylamide Compounds having a (meth) acryloyl group; monoalkyl esters of unsaturated dicarboxylic acids such as monobutyl ester of fumaric acid and monobutyl ester of maleic acid, and maleic anhydride. The (meth) acryloyl group refers to an acryloyl group and a methacryloyl group.

  Among the compounds having a (meth) acryloyl group, examples of the compound having one (meth) acryloyl group include N-vinylpyrrolidone, tetrahydrofurfuryl (meth) acrylate, 2-ethylhexyl acrylate, and 2-hydroxyethyl (meth). Hydroxyalkyl (meth) acrylates such as acrylate and 2-hydroxypropyl (meth) acrylate, and (meth) acrylates of phenolic alkylene oxide adducts such as ethylene oxide oxide adducts of phenol, and ethylenes of alkylphenols such as nonylphenol (Meth) acrylates of alkylene oxide adducts of alkylphenols such as oxide adducts, and (meth) acrylates of ethylene oxide adducts of 2-ethylhexanol. Rate aliphatic alkylene oxide adduct of an alcohol (meth) acrylates such as and the like. The above alkyl is a lower alkyl group which may be branched, and specifically has 1 to 6 carbon atoms such as ethyl and propyl. Moreover, said alkylene is a lower alkyl group which may have a branch, and is a C1-C6 thing like ethylene, propylene, etc. specifically ,. Moreover, said alkylene oxide consists of good lower alkylene like ethylene and propylene. Two or more of these compounds can be used in combination in the cationic curable composition of the present invention.

  Among the compounds having a (meth) acryloyl group, as a compound having two or more acryloyl groups in one molecule, diacrylate of ethylene oxide-modified bisphenol F (for example, “Aronix M208” manufactured by Toagosei Co., Ltd.), ethylene oxide Diacrylate of modified bisphenol A (for example, “Aronix M210” manufactured by Toagosei Co., Ltd.), diacrylate of propylene oxide modified bisphenol A (for example, “Light acrylate BP-4PA” manufactured by Kyoeisha Chemical Co., Ltd.), ethylene oxide modified isocyanuric acid Diacrylate (for example, “Aronix M215” manufactured by Toagosei Co., Ltd.), polypropylene glycol diacrylate (for example, “Aronix M225” manufactured by Toagosei Co., Ltd.), polyethylene glycol diacrylate (eg, For example, “Aronix M240” manufactured by Toagosei Co., Ltd.), polytetramethylene glycol diacrylate (for example, “Light acrylate PTMGA-250” manufactured by Kyoeisha Chemical Co., Ltd.), pentaerythritol diacrylate monostearate (for example, Toagosei Co., Ltd.) Manufactured by “Aronix M233”), neopentyl glycol diacrylate, hexanediol diacrylate, nonanediol diacrylate, dimethylol tricyclodecane diacrylate (for example, “light acrylate DCP-A” manufactured by Kyoeisha Chemical Co., Ltd.), trimethylolpropane Acrylic acid benzoate ester (for example, “Light acrylate BA-134” manufactured by Kyoeisha Chemical Co., Ltd.), hydroxypivalate neopentyl glycol diacrylate (for example, “Rye acrylate manufactured by Kyoeisha Chemical Co., Ltd.”) Acrylate HPP-A "), pentaerythritol triacrylate (for example," Aronix M305 "manufactured by Toagosei Co., Ltd.), trimethylolpropane triacrylate (for example," Aronix M309 "manufactured by Toagosei Co., Ltd.), alkylene oxide-modified trimethylolpropane Triacrylate (for example, “Aronix M310”, “Aronix M350” manufactured by Toagosei Co., Ltd.), triacrylate of ethylene oxide modified isocyanuric acid (for example, “Aronix M315” manufactured by Toagosei Co., Ltd.), glycerol triacrylate, alkylene oxide modified Glycerol triacrylate (for example, “Kayarad GPO-303” manufactured by Nippon Kayaku Co., Ltd.), pentaerythritol tetraacrylate (for example, “Aronix manufactured by Toagosei Co., Ltd.) M450 "), dipentaerythritol hexaacrylate (for example," Aronix M400 "manufactured by Toagosei Co., Ltd.), ditrimethylolpropane tetraacrylate (for example," Aronix M458 "manufactured by Toagosei Co., Ltd.), urethane acrylate (for example, Toagosei Co., Ltd.) ) "Aronix M1100", "Aronix M1200", "Aronix M1600"), polyester acrylate (for example, "Aronix M6100", "Aronix M7100" manufactured by Toagosei Co., Ltd.), an acrylic acid adduct of alkylene glycol diglycidyl ether ( For example, “Epoxy ester 70PA” manufactured by Kyoeisha Chemical Co., Ltd.), acrylic acid adduct of bisphenol A diglycidyl ether (eg “Lipoxy VR60” manufactured by Showa High Polymer Co., Ltd.), phenol Acrylic acid adduct of volac type epoxy resin (for example, “Lipoxy H600” manufactured by Showa Polymer Co., Ltd.), Acrylic acid adduct of brominated bisphenol A diglycidyl ether (for example “Lipoxy SP510” manufactured by Showa Polymer Co., Ltd.) Etc. Two or more of these compounds may be used as desired.

  In addition to these, various monomers, oligomers, polymers, and the like can be added to the composition of the present invention as long as they do not inhibit cationic polymerization.

You may mix | blend fillers, such as a silica, an alumina, and another metal oxide, with the composition of this invention as needed. Thereby, the thixotropy can be imparted.
In addition, when used as an electrical insulating material or when using a corrosive base material, it is preferable to blend a material having ion exchange capacity, more preferably an inorganic material, and particularly preferably an anion exchange. It has the ability. Examples of suitable inorganic anion exchangers include IXE-500, IXE-530, IXE-550, IXE-700, and IXE-800 (all manufactured by Toagosei Co., Ltd.).

  Furthermore, a coupling agent such as a silane coupling agent can be added to the composition of the present invention for the purpose of improving the adhesion of the cured product to the inorganic material. Suitable silane coupling agents include β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane (manufactured by Shin-Etsu Chemical, KBM-303), γ-glycidoxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical, KBM-403). ), Γ-glycidoxypropyltriethoxysilane (manufactured by Shin-Etsu Chemical, KBE-403), γ-glycidoxypropylmethyldiethoxysilane (manufactured by Shin-Etsu Chemical, KBM-402), 3-ethyl-3-{[3 -(Triethoxysilyl) propoxy] methyl} oxetane (manufactured by Toagosei Co., Ltd., OXT-610).

  For the purpose of improving heat resistance, an antioxidant can be blended in the composition of the present invention. Examples of the antioxidant contained in the composition of the present invention include phenolic antioxidants, sulfur antioxidants, phosphorus antioxidants, and amine antioxidants. Particularly preferred are phenolic antioxidants. It is an agent.

  Examples of phenolic antioxidants include hydroquinone monomethyl ether, 2,6-di-t-butylhydroxytoluene (for example, BHT manufactured by Kawaguchi Chemical), 2,2′-methylenebis- (4-methyl-6-t-butylphenol), 4,4′-butylidenebis- (3-methyl-6-tert-butylphenol), triethylene glycol-bis- [3- (3′-tert-butyl-4-hydroxy-5-methylphenyl)] propionate, pentaerythritol -Tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] (Irganox 1010 manufactured by Ciba Specialty Chemicals), n-octadecyl-3-[(3 ', 5'-di -T-butyl-4′-hydroxyphenyl) propionate], 4,4′-thiobis ( - methyl -6-t-butyl) phenol, and the like.

When the composition of the present invention is used for applications where transparency is not required, powdery reinforcing agents and fillers, for example, metal oxides such as aluminum oxide and magnesium oxide, calcium carbonate, magnesium carbonate Metal carbonates such as diatomaceous earth, basic magnesium silicate, calcined clay, fine powder silica, fused silica, crystalline silica and other metal compounds, aluminum hydroxide and other metal hydroxides, kaolin, mica, quartz It may contain powder, graphite, molybdenum disulfide, etc., and fiber reinforcing agents and fillers such as glass fiber, ceramic fiber, carbon fiber, alumina fiber, silicon carbide fiber, boron fiber, polyester fiber and polyamide fiber. it can. These can be blended in an amount of 10 to 900 parts by weight based on 100 parts by weight of the composition of the present invention.
Furthermore, if necessary, colorants, pigments, flame retardants such as titanium dioxide, iron black, molybdenum red, bitumen, ultramarine, cadmium yellow, cadmium red, antimony trioxide, red phosphorus, bromine compounds and triphenyl phosphate. Can be blended. These can be blended in an amount of 0.1 to 20 parts by weight with respect to 100 parts by weight of the composition of the present invention.

  Furthermore, various curable monomers, oligomers, and synthetic resins can be blended in the composition of the present invention for the purpose of improving the properties of the resin in a molded article or the like. For example, a diluent for epoxy resin such as monoepoxy, phenol resin, alkyd resin, melamine resin, fluorine resin, vinyl chloride resin, acrylic resin, silicone resin, polyester resin, etc. it can. The blending ratio of these resins is preferably 50 parts by weight or less with respect to 100 parts by weight of the composition of the present invention, that is, an amount within a range not impairing the cationic polymerizability that is the original property of the composition of the present invention.

  Examples of the means for blending the composition and optional components of the present invention include heat-melt mixing, roll, melt-kneading using a kneader, wet mixing using an appropriate organic solvent, and dry mixing.

The composition of the present invention is cured by heat when a thermal cationic polymerization initiator is used, and by active energy rays when an active energy ray cationic polymerization initiator is used. In the case of thermal cationic polymerization, the thermal cationic polymerization initiator is usually carried out at a temperature at which the generation of cationic species or Lewis acid is started, and is usually carried out at 50 to 200 ° C.
When polymerization is performed by heat, heat can be applied by a generally known method, and the conditions are not particularly limited.

Since the composition containing the formula (4) of the present invention has a small oxygen inhibition during polymerization, it can be cured by irradiation with a small amount of active energy rays (such as ultraviolet rays). The same applies to polymerization by heat.

Examples of the method of using the composition containing Formula (4) of the present invention include a method of irradiating ultraviolet rays after applying the composition to a substrate. Examples of the base material include molded resin processed products (plastic) such as polycarbonate and polymethyl methacrylate, metal, glass, concrete, wood such as natural wood and synthetic wood, stone, and paper.

Since the cationic curable ultraviolet curable composition of the present invention has very little yellowing after curing, it requires transparency for display materials such as liquid crystal displays, plasma displays, touch panels, and optical lenses. It can be suitably used as an optical material. That is, the cured product of the composition of the present invention can be suitably used for an optical material.
The usage example of the composition of this invention is illustrated below. For example, it can be used for a lens sheet or a light guide plate of a liquid crystal display or the surface thereof. In addition, as a diffusion sheet used as a binder for liquid crystal displays and the like, as a hard coat on the surface of various films such as deflecting films for liquid crystal displays, etc. Can be used as In addition, as other specific examples, as a coating for plasma display and touch panel wiring, as a glue for the screen screen, as a touch panel dot spacer, as a DVD substrate, as a DVD adhesive, As a DVD coating layer, it can be used as an optical waveguide core or cladding, as a lens for various optical devices, as a blue LED sealing portion, and as a white LED sealing portion.

  The cured product of the composition of the present invention has a high refractive index and excellent curability, heat resistance, flame retardancy, and mechanical properties. Therefore, it can be used for paints, coating materials, adhesives and the like.

<Example>
Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. However, the present invention is not limited to these examples. The% described below is% by weight.

<Example 1>
Synthesis of 2-[(3-ethyloxetane-3-yl) methoxy] biphenyl (2-BPMOX) Into a 1000 ml four-necked flask equipped with a thermometer, a condenser, a stirrer and a dropping funnel, 1 mol o- Phenylphenol, 1.2 mol of 3-chloromethyl-3-ethyloxetane (manufactured by Toagosei Co., Ltd.), 0.02 mol of tetrabutylammonium bromide were added, and 140.3 g of 48 was added while stirring at 75 ° C to 90 ° C. % Potassium hydroxide aqueous solution (corresponding to 1.2 mol) was added dropwise. After completion of the dropwise addition, the reaction solution was stirred for 9 hours while maintaining at about 110 ° C. The reaction solution was cooled to room temperature, washed with 250 g of water, and separated into an organic layer and an aqueous layer. The obtained organic layer was washed once with 100 g of water. The obtained organic layer was purified by distillation under reduced pressure (173 ° C. to 174 ° C., 400 Pa), and 2-[(3-ethyloxetane-3-yl) methoxy] biphenyl (the following formula (9)) was 220 as a colorless transparent liquid. 0.7 g (yield: 82%, purity: 99%) was obtained.
¹ H-NMR (CDCl ₃ ; 270 MHz) δ (ppm): 7.50 to 7.29 (7H, m), 7.25 to 7.02 (2H, m), 4.42 (2H, d, J = 6.1 Hz), 4.35 (2H, d, J = 6.1 Hz), 4.08 (2H, s), 1.73 (2H, q, J = 7.6 Hz), 0.81 (3H) , T, J = 7.6 Hz).

<Example 2>
Synthesis of 4-[(3-ethyloxetane-3-yl) methoxy] biphenyl (4-BPMOX) Into a 1000 ml four-necked flask equipped with a thermometer, a condenser, a stirrer and a dropping funnel, 1 mol of p- Phenylphenol, 1.5 mol of 3-chloromethyl-3-ethyloxetane, and 0.04 mol of tetrabutylammonium bromide were added, and while stirring at 90 ° C., 140.3 g of 48% aqueous potassium hydroxide solution (1.2 mol) was added. Equivalent) was added dropwise. After completion of the dropwise addition, the reaction solution was stirred for 14 hours while maintaining at about 110 ° C. Thereafter, 0.3 mol of 3-chloromethyl-3-ethyloxetane and 0.02 mol of tetrabutylammonium bromide were added to the reaction solution, and the reaction solution was further stirred for 3 hours while maintaining the temperature at about 110 ° C. After cooling this reaction liquid to room temperature, 250 g of water and 250 g of toluene were added for extraction, and the organic layer and the aqueous layer were separated. The obtained organic layer was washed with 250 g of water three times. The obtained organic layer was evaporated under reduced pressure to obtain 255 g of a crude product. This crude product was purified by distillation under reduced pressure (192 ° C. to 196 ° C., 400 Pa) to give 223.1 g of 4-[(3-ethyloxetane-3-yl) methoxy] biphenyl (the following formula (10)) as a white solid. (Yield: 83%, purity: 99%).
¹ H-NMR (CDCl ₃ ; 270 MHz) δ (ppm): 7.57 to 7.27 (7H, m), 7.04 to 6.98 (2H, m), 4.59 (2H, d, J = 6.1 Hz), 4.50 (2H, d, J = 6.1 Hz), 4.12 (2H, s), 1.90 (2H, q, J = 7.6 Hz), 0.95 (3H) , T, J = 7.6 Hz).
mp: 67.8-68.3 ° C

Preparation of composition After mixing in accordance with the usual method with the component shown in Table 1, and its ratio, after preparing the cationic curable ultraviolet curable composition, various physical properties were evaluated. The abbreviations in Table 1 indicate the following compounds. The numerical values in Table 1 are parts by weight.
YD128: Bisphenol A type epoxy resin (manufactured by Toto Kasei Co., Ltd.)
OPP-G: Orthophenylphenol glycidyl ether (Sanko)
UVR6110: 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate 2-BPMOX: Compound synthesized above 4-BPMOX: Compound synthesized above POX: 3-ethyl-3- (phenoxymethyl) oxetane (Toagosei) (Aron Oxetane OXT-211)
2,2′-BPDOX: a compound represented by the following formula (11) (developed by Toagosei Co., Ltd.)
RSOX: a compound represented by the following formula (12) (developed by Toagosei Co., Ltd.)
HQOX: a compound represented by the following formula (13) (developed by Toagosei Co., Ltd.)
TMPOX: a compound represented by the following formula (14) (developed by Toagosei Co., Ltd.)
A200: Acrylate having an alicyclic epoxy group (Daicel Chemical Industries, Ltd., Cyclomer A200)
UVI-6992: Triarylsulfonium hexafluorophosphate (manufactured by Dow Chemical Japan, photocationic polymerization initiator)

○ Evaluation of transparency of cured products (Part 1)
Transparency evaluation was performed on the compositions obtained by irradiating the compositions of Examples 3 to 7 and Comparative Example 1 with ultraviolet rays. That is, two double-sided tapes were affixed to one side of a 1 mm thick slide glass to form a spacer, the composition was placed between them, and sandwiched between the same slide glass from above to be irradiated with ultraviolet rays and cured. The ultraviolet irradiation conditions were a 60 W / cm high-pressure mercury lamp, a lamp height of 30 cm (150 mW / cm ² ), an irradiation time of 20 seconds, and irradiation was performed only from one side. For reference, the UV-visible absorption spectrum of the slide glass used is shown in FIG. The thickness of the resin part after curing was about 0.25 mm.
The visible absorption spectrum of this cured product was measured without inserting a substrate or the like on the reference light side in a state of being sandwiched between two glass slides. The measurement results are shown in FIG. 2 (transmittance spectrum at 380 to 700 nm) and Table 3 (transmittance at 400 nm and 380 nm). Compared with Comparative Example 1, the example clearly has a high transmittance around 400 nm and a small yellowing.

○ Evaluation of transparency of cured products (Part 2)
Transparency was evaluated for the compositions of Example 3 and Comparative Examples 2 to 5 that were cured by irradiating with ultraviolet rays. That is, a PET film having a thickness of 50 μm from the top (Toray Industries, Inc.) was used for the purpose of smoothing the cured surface by placing the composition in one side of the PMMA substrate having a thickness of 1 mm using double-sided tape as a spacer. ) Lumirror 50-T60) was laminated and irradiated with ultraviolet rays to be cured. The ultraviolet irradiation conditions were a 60 W / cm high-pressure mercury lamp, a lamp height of 30 cm (150 mW / cm ² ), an irradiation time of 30 seconds, and irradiation was performed only from the PET side. For reference, the UV-visible absorption spectrum of the used PET film is shown in FIG. Thereafter, the PET film was removed and irradiated for 15 seconds in order to see yellowing when the light from the light source was directly irradiated. The thickness of the resin part after curing was about 0.25 mm.
The visible absorption spectrum of this cured product was measured by inserting the PMMA substrate on the reference light side together with the PMMA substrate. The measurement results are shown in FIGS. As compared with Comparative Examples 2 to 5, Example 3 clearly has a high transmittance around 400 nm and small yellowing.

○ Curability and Adhesiveness of Coating Film Evaluations of curability and adhesiveness were carried out for the compositions of Examples 3 to 5, Comparative Example 2 and Comparative Example 3.
That is, each composition was applied to a 20 μm thick bar coater on a 50 μm thick untreated surface PET film (Toray Industries, Ltd., Lumirror 50-T60), and then a 80 W / cm condensing high-pressure mercury lamp ( 1 light), at a lamp height of 10 cm, and passed once at a conveyor speed of 10 m / min or 30 m / min and irradiated with ultraviolet rays, and the curability (the state of the coating film) was examined by touch. The curability results are shown in Table 4. As for the curability in Table 4, “◯” represents a cured coating film without tack, “Δ” represents a cured coating film with tack, and “x” represents a liquid state. As a result, the compositions of Examples 3 and 4 are superior in curability as compared to the compositions of Example 5, Comparative Example 2, and Comparative Example 3. The atmosphere at the time of ultraviolet irradiation is 20 ° C., 54% R.D. H. Met.
About adhesion, the cross-cut peel test was implemented according to JISK-5400, and it determined as follows.
×: Fully peeled at the interface between PET and UV curable resin Δ: Partially peeled ○: No peeling at the interface and no destruction of the substrate or coating film ◎: No peeling at the interface and base The material (PET film) is destroyed. ●: There is no interfacial peeling, and the coating film (ultraviolet curable resin) is destroyed. Also, the refractive index of the cured coating film (cured at 10 m / min) Measured using an Abbe refractometer (25 ° C., sodium D line).
These results are also shown in Table 4.

  When the refractive indexes of Example 3 and Comparative Example 3 are compared, Example 3 is higher. This indicates that it is better to use a compound having one oxetanyl group than a compound having two oxetanyl groups. Further, as can be seen from Example 3 and Example 4, it is shown that a coating film having good adhesion and transparency can be obtained and the refractive index can be controlled.

  Since the cationic curable ultraviolet curable composition of the present invention has very little yellowing after curing, it requires transparency for display materials such as liquid crystal displays, plasma displays, touch panels, and optical lenses. It can be suitably used as an optical material. In addition, the cured product obtained from the composition containing the compound represented by formula (4) of the present invention has a high refractive index and is excellent in curability, heat resistance, flame retardancy, and mechanical properties. It can be used for paints and coating materials, adhesives and the like.

Claims (10)

At least one compound represented by the following formula (4) :
An ultraviolet curable composition comprising Compound A having two or more cationically polymerizable groups and a cationic photopolymerization initiator.

(In Formula (4) , R ¹ represents a hydrogen atom or a methyl group, R ² represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, n represents an integer of 0 to 20, and B represents a carbon number. 1 to 6 alkyl groups, C 1 to C 6 alkoxy groups or halogen atoms, B substituent number L represents an integer from 0 to 5, and B substituent number m is an integer from 0 to 4 Represents .)   The composition according to claim 1, further comprising Compound B having one cationically polymerizable group.   The composition according to claim 1 or 2, wherein the cationic photopolymerization initiator is a sulfonium salt.   Hardened | cured material formed by irradiating an ultraviolet-ray to the composition of Claim 1 or 2.   A cured product obtained by irradiating the composition according to claim 3 with ultraviolet rays.   The cured product according to claim 4, wherein the cured product is an optical material.   The cured product according to claim 5, wherein the cured product is an optical material. A compound represented by the following formula (4).

(In Formula (4), R ¹ represents a hydrogen atom or a methyl group, R ² represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, n represents an integer of 0 to 20, and B represents a carbon number. 1 to 6 alkyl groups, C 1 to C 6 alkoxy groups or halogen atoms, B substituent number L represents an integer from 0 to 5, and B substituent number m is an integer from 0 to 4 Represents.)   A cationic curable composition comprising a compound represented by formula (4) according to claim 8 and a cationic polymerization initiator. A process for producing a compound represented by the formula (4) , comprising reacting a compound represented by the formula (5) with a compound represented by the formula (6) in the presence of an alkali.

(In Formula (5), R < ¹ > represents a hydrogen atom or a methyl group, n represents the integer of 0-20, B is a C1-C6 alkyl group, a C1-C6 alkoxy group, or Represents a halogen atom, the number L of substituents of B represents an integer of 0 to 5, and the number of substituents m of B represents an integer of 0 to 4).

(In Formula (6), R ² represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.)

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