JP2879563B2 - toner - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner, and more particularly, to an excellent low-temperature fixing property and a non-image fixing property used for developing a latent image formed by an electrostatic printing method or the like. The present invention relates to a toner having a good balance between offset properties and blocking resistance.

[Summary of the Invention]

By using a specific crosslinked polyester as a binder, the toner of the present invention has a well-balanced low-temperature fixing property, non-offset property and blocking resistance, which are extremely useful in the electrostatic recording industry.

[Conventional technology]

Conventionally, in electrophotography, usually, a latent image is formed on a latent image forming roller composed of a photoconductive photoreceptor by charging and exposing, developed with toner, and the obtained toner image is transferred onto paper or the like. The image is fixed on paper by heating and pressing to obtain an image.

It is desired that the image forming process through such a latent image is performed at a high speed. For this reason, a flash fixing system and a heat roller fixing system, which have high thermal efficiency and can be operated at high speed in a fixing process, are widely used.

In recent years, there has been a strong demand for higher speed, and for that purpose, high-speed fixing of toner images is a condition. In order to fix a toner image at a high speed in a heat fixing method, it is required that the toner has a good low-temperature fixing property. To that end, the softening temperature of a binder, which is a main component of the toner, is lowered, and the adhesive property is lowered. Need to be improved. On the other hand, in the heat roller fixing method, when the softening temperature of the binder of the toner is lowered, a part of the toner is transferred to the heat roller during the fixing process, and a phenomenon (offset) that stains the next paper or the like is likely to occur.

Various proposals have been made as a result of various research and development efforts to solve such problems.

A first proposal is to obtain a linear polyester by reacting an etherified bisphenol A component and a dicarboxylic acid component, and then to form a trivalent or higher valent monomer component (for example,
(Trimellitic anhydride) was added to form a crosslinked structure, and a crosslinked polyester obtained as a binder was used.
It relates to a toner having good non-offset properties.

The second proposal relates to a method for improving the flowability of a toner by lowering the molecular weight of a binder in order to improve the low-temperature fixability.

A third proposal relates to a binder having a long-chain aliphatic hydrocarbon unit as a binder in order to improve low-temperature fixability.

[Problems to be solved by the invention]

However, the first proposal has a problem that the fixing performance is not always good, and when high-speed fixing at a fixing speed of 50 sheets / min or more is continuously performed, the toner is not sufficiently heated and the fixing strength is likely to be insufficient. there were.

In the second proposal, it has been clarified that, according to the method for reducing the molecular weight, the offset performance is reduced, and it is impossible to produce a toner that can withstand practical use.

Further, the third proposal has a problem that the glass transition temperature of such a polyester is low and storage stability is poor.

An object of the present invention is to solve the above-mentioned disadvantages, and to provide a toner having excellent low-temperature fixability, non-offset property and blocking resistance in a well-balanced manner.

[Means for solving the problem]

The toner of the present invention is characterized in that the binder is the following crosslinked polyester.

(A) a trihydric or higher polyhydric alcohol unit and / or a trihydric or higher polyhydric carboxylic acid unit, (b) 5 to 80 mol% of an aliphatic dicarboxylic acid having 3 to 8 carbon atoms with respect to all acid units, and At least one kind of a branched aliphatic monomer unit selected from the group consisting of aliphatic diols, (c) an aromatic dicarboxylic acid unit, (d) an aromatic diol unit of 80 mol% or less based on all acid units, and ( e) a non-linear polycondensate comprising ethylene glycol units having an acid value of 0.5 to 16 mg KOH
/ g, a crosslinked polyester having a glass transition temperature of 30 to 68 ° C, a b value of 20 or less, and a softening temperature of 155 ° C or less.

Further, the toner of the present invention is characterized in that the binder is the following crosslinked polyester.

(A) a trihydric or higher polyhydric alcohol unit and / or a trihydric or higher polyhydric carboxylic acid unit, (b) 1 mol% or more of all acid units and a polyoxyalkylene glycol unit having 4 to 20 carbon atoms, A non-linear polycondensate composed of (c) an aromatic dicarboxylic acid unit, (d) an aromatic diol unit of 80 mol% or less based on all acid units, and (e) an ethylene glycol unit, having an acid value of 0.5 ~ 16mgKOH
/ g, a crosslinked polyester having a glass transition temperature of 30 to 68 ° C, a b value of 20 or less, and a softening temperature of 155 ° C or less.

In the present specification, the total acid unit means a total unit of a trivalent or higher polycarboxylic acid unit, an aliphatic dicarboxylic acid unit and an aromatic dicarboxylic acid unit in a branched aliphatic monomer having 3 to 12 carbon atoms. The dicarboxylic acid unit means a total unit of an aliphatic dicarboxylic acid unit and an aromatic dicarboxylic acid unit in a branched aliphatic monomer having 3 to 12 carbon atoms.

The acid value is measured by a neutralization titration method, the glass transition temperature is measured by a differential scanning calorimeter (DSC), the b value is measured by a colorimeter, and the softening temperature is measured by a flow tester (CFT-500, manufactured by Shimadzu Corporation). The value measured by the method of measuring the temperature at which 1/2 of a 1 g sample flows out when measured under a 1 mmφ × 10 mm nozzle, a load of 30 kg, and a constant temperature increase of 3 ° C./min. It is.

The trihydric or higher polyhydric alcohol unit constituting the crosslinked polyester used in the present invention is a unit in which a trihydric or higher polyhydric alcohol is generated in correspondence with a carboxylic acid. is there.

(HO _m R ₁ O-) _n (where m and n are integers satisfying m + n ≧ 3, m ≧ 0, and n ≧ 1, and R ₁ is a hydrocarbon residue.) As polyhydric alcohols,
For example, sorbitol, 1,2,3,6-hexanetetrol, 1,4-sulfitan, pentaerythritol, dipentaerythritol, tripetaerythritol, sucrose, 1,2,4-butanetriol, 1,2,5 -Pentanetriol, glycerol, 2-methylpropanetriol,
2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxymethylbenzene, etc. can be introduced into a crosslinked polyester by reacting with a carboxylic acid component. It is. On the other hand, the trivalent or higher polyvalent carboxylic acid unit is a unit formed by reacting a trivalent or higher polyvalent carboxylic acid component with an alcohol, and is expressed as follows.

(R ₃ OCO _{m ′} R ₂ CO−) _{n ′} (where m ′ and n ′ are m ′ + n ′ ≧ 3, m ′ ≧ 0, n ′
Satisfies ≧ 1), R ₂ is a hydrocarbon residue,
R ₃ is an alkyl group having 6 or less carbon atoms or a hydrogen atom. ) The polyvalent carboxylic acid constituting such a unit includes:
For example, 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid 1,2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxylpropane, tetra (methylenecarboxyl) methane, 1,2,7 , 8
-Octanetetracarboxylic acid, or their acid anhydrides, or their lower alkyl esters having 6 or less carbon atoms can be introduced into a crosslinked polyester by reacting with an alcohol.

The units introduced by these trivalent or higher-valent monomers are not particularly limited, but the total amount is based on the total amount of the acid units in the crosslinked polyester, that is, the units generated by the reaction of the carboxylic acid with the alcohol. On the other hand, 1 to 30 mol% is preferable.

If the content of these units exceeds 30 mol%, the low-temperature fixability of the toner tends to decrease, and if it is less than 1 mol%, a sufficient crosslinked structure cannot be obtained and offset may easily occur.

The branched aliphatic monomer unit having 3 to 12 carbon atoms constituting the crosslinked polyester used in the present invention is introduced by reacting an aliphatic diol or an aliphatic dicarboxylic acid having 3 to 12 carbon atoms having a side chain. The unit is as follows.

[However, i, j, k, i ', j', k 'are i + k = 2,
j ≧ 0, k ≧ 1; j ′ + k ′ = 2, j ′ ≧ 0, and k ′ ≧ 1 are integers, and R ₅ and R ₇ are alkyl groups (provided that i,
When i ′ ≧ 2, different groups may be used), and R ₄ and R ₆
Is a hydrocarbon residue, and R ₈ is an alkyl group having 6 or less carbon atoms or a hydrogen atom. Examples of the branched aliphatic monomer having 3 to 12 carbon atoms constituting such a unit include, for example, 1,2-propylene glycol, 1,3-butanediol, 2,3-butanediol,
Methyl-1,3-propanediol, neopentyl glycol, 1,2-dimethyl-1,3-propanediol, 1,3-
Dimethyl-1,3-propanediol, 1,2,3-trimethyl-1,3-propanediol, 2,3-trimethyl-1,4-butanediol, 3,3-diethyl-1,5-pentanediol, etc. Branched aliphatic glycol, 1,2-propanedicarboxylic acid, 1,3-butanedicarboxylic acid, 2,3-butanedicarboxylic acid, 3-methylglutaric acid, 2,2-dimethyl-1,3-propanedicarboxylic acid, 1,3-dimethyl-1,3-propanedicarboxylic acid, 1,3-dimethyl-1,3-propanedicarboxylic acid, 1,2,3-trimethyl-1,3-propanedicarboxylic acid,
Branched aliphatic dicarboxylic acids such as 2,3-dimethyl-1,4-butanedicarboxylic acid and 3,3-diethyl-1,5-pentanedicarboxylic acid or lower alkyl esters of these having 6 or less carbon atoms, and the like. Units can be introduced into the crosslinked polyester by reacting them with an acid or alcohol.

On the other hand, the polyoxyalkylene glycol unit having 4 to 20 carbon atoms is a unit into which the polyoxyalkylene glycol has been introduced by reacting with the acid component.

HO- (RO-) _i or -O- (RO-) _i (where i is an integer and R is an alkylene group) C4 to C20 polyoxyalkylene glycol constituting such a unit As, for example, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol having an average molecular weight of less than 450, ditrimethylene ether glycol, tritrimethylene diether glycol, ethylene propylene ether glycol, ditetramethylene ether glycol,
Ethylene tetramethylene ether glycol, trimethylene tetramethylene ether glycol, polyoxytetramethylene glycol having a molecular weight of 350 or less,
The units can be introduced into the crosslinked polyester by reacting them with an acid component.

The presence of these units not only is effective in increasing the glass transition temperature and lowering the softening temperature, but also contributes to the improvement of the solubility parameter (SP) of the resin, and provides excellent blocking resistance and low-temperature fixability to the toner. Is to be granted. In the present invention, at least one kind of branched aliphatic monomer unit selected from the group consisting of aliphatic dicarboxylic acids having 3 to 8 carbon atoms and aliphatic diols has the above-mentioned remarkable effect as a toner binder. From the viewpoint, 5 to 5
The range is 80 mol%. When the polyoxyalkylene glycol unit having 4 to 20 carbon atoms is contained in an amount of 1 mol% or more based on all the acid units, the above-mentioned effect as a toner binder can be exhibited. If the proportion of these units is too large, the reactivity will decrease due to the steric structure of the monomer, and a longer time will be required for the polycondensation reaction, and as a result, the productivity will decrease. When these carbon numbers exceed 8 in the branched aliphatic monomer unit and exceed 20 in the polyoxyalkylene glycol unit,
The glass transition temperature tends to decrease, and as a result, the blocking resistance as a toner binder tends to be impaired.

The aromatic dicarboxylic acid unit constituting the crosslinked polyester used in the present invention is a unit formed by reacting an aromatic dicarboxylic acid component with an alcohol, and is represented by the following formula.

(R ₁₀ OCO _{j ″} R ₉ CO−) _{k ″} (where j ″ and k ″ are j ″ + k ″ = 2, j ″ ≧ 0, k ″
Is an integer satisfying ≧ 1, R ₉ is an aromatic hydrocarbon residue, and R ₁₀ is an alkyl group having 6 or less carbon atoms or a hydrogen atom. As the aromatic dicarboxylic acid constituting such a unit, for example, terephthalic acid, isophthalic acid, orthophthalic acid, cyclohexanedicarboxylic acid, 3,5-toluenedicarboxylic acid, 2,4-trienedicarboxylic acid, 2,5- Examples thereof include dicarboxylic acids such as toluenedicarboxylic acid and the like, acid anhydrides thereof and lower alkyl esters having 6 or less carbon atoms, and the units thereof can be introduced into a crosslinked polyester by reacting them with an alcohol. Contributes to the improvement of the glass transition temperature. Among these, units introduced from terephthalic acid and isophthalic acid (respectively referred to as terephthalic acid units and isophthalic acid units) are preferable in order to significantly lower the softening temperature of the crosslinked polyester. The content ratio is preferably such that the terephthalic acid unit is 50 mol% or more based on all dialbonic acid units and the isophthalic acid unit is 50 mol% or less based on all dicarboxylic acid units in consideration of the effect on the glass transition temperature. . If the terephthalic acid unit is too small and the isophthalic acid unit is too large, the glass transition temperature decreases.

The aromatic diol unit constituting the crosslinked polyester used in the present invention refers to a unit generated by reacting an aromatic diol with a carboxylic acid, and is represented by the following formula.

(HO _j R ₉ O−) _k (where j and k are j + k = 2, j ≧ 0, k
Is an integer satisfying ≧ 1, and R ₉ is an aromatic hydrocarbon residue. ) As the aromatic diol constituting such a unit,
For example, polyoxypropylene-2, -bis (4'-hydroxyphenyl) propane, polyoxyethylene-2,2
-Bis (4'-hydroxyphenyl) propane, etc., whose units can be introduced into the crosslinked polyester by reacting them with a carboxylic acid, which contributes to lowering the softening temperature. Among these, to significantly improve the glass transition temperature, and to significantly lower the softening temperature,
Polyoxypropylene-2,2-bis (4'-hydroxyphenyl) propane is preferred. When the diol is used in a proportion exceeding 80% based on the total acid units, the reactivity tends to decrease. It is preferred that On the other hand, the ethylene glycol unit is a unit shown below.

—O—CH ₂ CH ₂ —O— or HO—CH ₂ CH ₂ —O— Such units can be introduced into the crosslinked polyester by reacting ethylene glycol with a carboxylic acid.

The crosslinked polyester used in the present invention needs to have the following physical properties.

Excellent thermal stability and charging stability which is the object of the present invention,
Therefore, the crosslinked polyester as a binder which has little thermal coloring and can be used as a toner for color printing needs to have an acid value of 16 mgKOH / g or less. However, in the case of polyester, in order to synthesize a polyester with an extremely low acid value, although technical methods such as lowering the reaction temperature have already been established, it is actually possible to obtain a polyester of 0.5 mg KOH / g or less. Above, difficult. That is,
The acid value of the crosslinked polyester used in the present invention is 0.5 to 1
If the acid value is out of this range, the thermal stability is extremely reduced as a general property of the polyester, and the charge stability, which is an important property of the toner, the hygroscopicity is increased, and It decreases due to the increase in the negative chargeability due to the group.

Further, the glass transition temperature is an important index for storage stability, but if the glass transition temperature is lower than 30 ° C., practical storage stability cannot be achieved. On the other hand, when the temperature exceeds 68 ° C., the softening time becomes excessively long and the fixing performance is adversely affected. A lower softening temperature is preferable for improving the fixing property,
Actually, there is no problem if the temperature is 155 ° C. or less.

Since the polyester binder according to the present invention is particularly excellent in thermal properties, the b value is easily reduced to 20 or less. As a binder for a thin toner in color printing, the b value is 20 or less, preferably the b value is 10 or less, and more preferably the b value is 6 or less. Of course, in black printing, which is the mainstream, the b value of the binder is not restricted at all.

The crosslinked polyester used in the present invention is prepared by a usual polyester synthesis method, that is, after an acid component and an alcohol component are subjected to an esterification reaction or a transesterification reaction, and then a low-boiling diol is removed from the system under vacuum or a nitrogen stream. It can be synthesized by removing it.

The toner of the present invention is a particle powder in which the above-mentioned crosslinked polyester contains a coloring agent or an additive used as needed.

Examples of the coloring agent include carbon black, methylene blue chloride (CINo. 52015), phthalocyanine blue (CINo. 74160), malachite green oxalate (CINo. 42000), and lamp black (CIN
o.77266), Rose Bengal (CINo.45435), Nigrosine dye (CINo.50415B), aniline blue (CINo.
50405), Calco Oil Blue (CINo.azoec Blue)
3), Chrome Yellow (CINo. 14090), Ultramarine Blue (CINo. 77103), Dupont Oil Red (C.
I. No. 26105), quinoline yellow (CI No. 47005), or a mixture thereof.

These colorants are preferably contained in a ratio sufficient to form a sufficiently thick visible image, and usually about 1 to 20 parts by weight based on 100 parts by weight of the crosslinked polyester.

Other additives include, for example, an anti-offset agent, a fluidity improver, and a charge control agent. Examples of the anti-offset agent include polyolefin-based wax, carnauba wax, and alkylenebisfatty acid amide compounds. Examples of the fluidity improver include, for example, fine silica powder, and examples of the charge control agent include, for example, an electron-donating dye (a nigyrosine-based dye), an alkoxylated amine, and a quaternary ammonium salt (containing an activator). ), Simple substances and compounds of alkylamides, phosphorus and tungsten, molybdate chelate pigments, fluorine-based activators and positive charge control agents such as hydrophobic silica; electron-accepting dyes (metal complex salts of monoazo dyes); Complex, chlorinated polyolefin, chlorinated polyester,
Negative charge control agents such as polyester having excess acid groups, sulfonylamine of copper phthalocyanine, oil black (CI ^* 26150), metal salts of naphthenic acid, metal salts of fatty acids, and resin acid soaps.

In the case of constituting a magnetic toner, a magnetic substance is added to the crosslinked polyester together with the colorant or alone.

As a magnetic material, ferrite, magnetite or other iron, cobalt, nickel, or other ferromagnetic metal or alloy or a compound containing these elements, or an alloy that becomes ferromagnetic when subjected to an appropriate heat treatment For example, an alloy of a type called a Heusler alloy containing manganese and copper, such as manganese-copper-aluminum and manganese-copper-tin, or chromium dioxide can be used.

These magnetic substances are in the form of fine particles having an average particle diameter of 0.1 to 1 μm, and the content thereof is preferably 20 to 70 parts by weight, more preferably 40 to 70 parts by weight, per 100 parts by weight of the toner.

Further, the toner of the present invention has a modifier for improving the pulverizability, an additive for improving the triboelectricity of the toner, or a toner substance attached to the surface of the carrier particles or the surface of the latent image carrier to perform these functions. A property improving agent such as an additive for preventing the occurrence of a so-called toner filming phenomenon, which lowers the property, may be added.

As such a property improver, for example, a fat which is an uncrosslinked polymer and does not contain chloroform-insoluble matter can be preferably used. Examples of the resin to be cut include styrene, parachlorostyrene, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, dodecyl acrylate, and n-acrylate.
Octyl, 2-chloroethyl acrylate, phenyl acrylate, α-methyl methyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, acrylonitrile, methacrylonitrile, acrylamide,
Vinyl methyl ether, vinyl isobutyl ether, vinyl ethyl ether, vinyl methyl ketone, vinyl hexyl ketone, N-vinyl pyrrole, N-vinyl carbazole, N-vinyl indole, N-vinyl pyrrolidone,
Vinyl chloride, vinyl bromide, vinyl fluoride, vinyl acetate,
Examples include homopolymers obtained by polymerizing vinyl monomers such as vinyl propionate, vinyl benzoate, and vinyl acetate, copolymers thereof, and mixtures of the polymers. Such a modifier can be used in a range that does not impair the properties of the crosslinked polyester, and can be used in a range that does not impair the properties of the crosslinked polyester, and is usually in an amount equal to or less than that of the crosslinked polyester. It may be used.

[Action]

The toner of the present invention has excellent non-offset properties because the binder is a cross-linked polyester, has a high glass transition temperature because of containing a branched aliphatic monomer component and the like, has a low softening temperature, and has adhesion to paper and various films. Is excellent. The fact that the glass transition temperature can be kept high is derived from the fact that the aliphatic monomer has a branched chain, and this effect is far greater than that of a linear aliphatic monomer. Further, the phenomenon of lowering the softening temperature is due to the introduction of the aliphatic monomer, and the phenomenon of improving the adhesive performance is due to the optimization of the SP value by the side chain of the branched aliphatic monomer. It is considered that an effect hardly comparable to that of the linear aliphatic monomer can be obtained by using the branched aliphatic monomer. As a result, the toner can stably behave as a single particle without aggregation during storage and during use, and at the time of fixing, high-speed printing can be performed without offsetting the toner to the heat roller.

Further, the crosslinked polyester has a low acid value and thus has not only excellent charge stability but also particularly excellent thermal stability, and is a polymer having low thermal coloring, that is, a low b value.
The development of a binder with less coloring greatly contributes to colorization of a copy or the like.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. In the examples, “parts” and “%” are all on a molar basis.

〔Example〕

Examples 1 to 9 Trivalent or higher carboxylic acids, branched aliphatic dicarboxylic acids, branched aliphatic diols, polyoxyalkylene glycols,
A monomer selected from an aromatic dicarboxylic acid, an aromatic diol and ethylene glycol is charged into an autoclave having a distillation bath and subjected to an esterification reaction. Then, 500 ppm of antimony trioxide is added to the acid component, and the mixture is placed under a vacuum of 3 torr. The polycondensation was carried out while removing the glycol from the system to obtain a crosslinked polyester as shown in Table 1.

Next, carbon black was added to the obtained cross-linked polyester and kneaded, cooled, pulverized, classified, and the average particle size was 10 to 13
As a result, a toner according to the present invention comprising particles of μm was obtained.

The composition, glass transition temperature, softening temperature, acid value and b value of each unit in the crosslinked polyester, the minimum fixing temperature, offset occurrence temperature and blocking resistance of the toner were examined.

The composition of each unit was determined by a liquid chromatograph and a gas chromatograph of a crosslinked polyester decomposed in accordance with a conventional method.

 Glass transition temperature was determined by DSC.

 The softening temperature was measured by a flow tester.

 The acid value was determined by a titration method.

 The b value was measured by a colorimeter.

The minimum fixing temperature consisted of a Teflon roller (heat roller) and a rubber roller. Using a device whose temperature could be set freely, the peripheral speed of the Teflon roller was set at 20 cm / sec and the toner image was transferred between both rollers. It was measured by a method of examining the toner fixing rate of a fixed image obtained by passing through paper. Here, the fixing rate of the toner was measured by using a reflection densitometer (manufactured by Macbeth) to measure the density of the toner before and after the cellotape (Nichiban No. 405) was applied and peeled off. The fixing temperature was the temperature at which the fixing rate reached 95%.

In the measurement of the offset occurrence temperature, the toner image is transferred according to the measurement of the minimum fixing temperature, the fixing process is performed by the above-described fixing device, and then the blank transfer paper is sent to the fixing device under the same conditions, and The operation of observing whether or not toner contamination occurs is performed by repeating the operation in a state configured based on the temperature of the heat roller of the fixing device, and the lowest temperature of the heat roller when toner contamination occurs is referred to as an offset generation temperature. And

The anti-blocking properties were as follows: each sample was kept at 50 ° C and 50% relative humidity.
%, The presence or absence of the temperature when left for 48 hours, and the degree thereof were evaluated. ◎ indicates very good, 良好 indicates good, 良好 indicates slightly poor, and × indicates bad.

Examples 10 to 17 Crosslinked polyesters as shown in Table 2 were obtained in the same manner as in Example 1 except that dibutyltin oxide was used as the condensation polymerization catalyst. The physical properties of the binder and the toner of the present invention produced by the same method as in Example 1 were measured. Example
As for No. 17, a toner of the present invention was obtained by adding 0.8% by weight of R-972 to powder obtained by adding, mixing, cooling, pulverizing and classifying carbon black. The results are shown in Table 2.

Examples 18 to 25 Crosslinked polyesters as shown in Table 3 were obtained in the same manner as in Examples 10 to 17. The physical properties of the crosslinked polyester and the toner produced by the same method as in Example 1 were measured. Third result
Shown in table Comparative Examples 1 to 8 Comparative polyester binders as shown in Table 4 were obtained in the same manner as in Examples 1 to 9. The properties of the binder and the toners manufactured in the same manner as in Examples 1 to 9 were measured. In Comparative Example 1, a toner was prepared by adding 0.8% by weight of R-972 to powder obtained by adding, mixing, cooling, pulverizing, and classifying carbon black. The results are shown in Table 4.

[Effects of the Invention] As described in detail above, the toner of the present invention has a low softening point and good adhesion to a substrate, so that it has excellent low-temperature fixability and also has excellent non-offset properties. In addition, since the lowering of the glass transition temperature was suppressed by the introduction of a branched monomer unit or the like, the blocking resistance was excellent, and the storage problems could be eliminated.

Therefore, high-speed development of a toner image can be stably performed, and high-speed copying and printing can be achieved, and its industrial value is extremely large.

Continuation of the front page (72) Inventor Ryo Funato 4-1-1-60 Sunadabashi, Higashi-ku, Nagoya City, Aichi Prefecture Inside Mitsubishi Rayon Co., Ltd. (72) Inventor Shinji Kubo 4-1-160 Sunadabashi, Higashi-ku, Nagoya City, Aichi Prefecture Mitsubishi Rayon Co., Ltd. In-company (56) References JP-A-54-86342 (JP, A) JP-A-62-78569 (JP, A) JP-A-61-284772 (JP, A) (58) Fields investigated (Int. . ⁶ , DB name) G03G 9/087

Claims (2)

(57) [Claims] 1. A toner, wherein the binder is the following crosslinked polyester. (A) a trihydric or higher polyhydric alcohol unit and / or a trihydric or higher polyhydric carboxylic acid unit, (b) 5 to 80 mol% of an aliphatic dicarboxylic acid having 3 to 8 carbon atoms with respect to all acid units, and At least one kind of a branched aliphatic monomer unit selected from the group consisting of aliphatic diols, (c) an aromatic dicarboxylic acid unit, (d) an aromatic diol unit of 80 mol% or less based on all acid units, and ( e) a non-linear polycondensate composed of ethylene glycol units, having an acid value of 0.5 to 16 mgKOH / g, a glass transition temperature of 30 to 68 ° C, and b
A crosslinked polyester having a value of 20 or less and a softening temperature of 155 ° C or less. 2. A toner wherein the binder is the following crosslinked polyester. (A) a trihydric or higher polyhydric alcohol unit and / or a trihydric or higher polyhydric carboxylic acid unit, (b) 1 mol% or more of all acid units and a polyoxyalkylene glycol unit having 4 to 20 carbon atoms, A non-linear polycondensate comprising (c) an aromatic dicarboxylic acid unit, (d) an aromatic diol unit of not more than 80 mol% based on the total acid units, and (e) an ethylene glycol unit, having an acid value of 0.5 ~ 16mgKOH / g, glass transition temperature 30 ~ 68 ℃, b
A crosslinked polyester having a value of 20 or less and a softening temperature of 155 ° C or less.