JPH0659506A - Electrostatic charge image developing toner - Google Patents

Abstract

PURPOSE:To decrease melt viscosity and to increase glass transition temp. by incorporating a resin which is obtd. by the reaction of epichlorohydrin and bisphenol A and has bisphenol A at least at one end. CONSTITUTION:The toner contains a resin which is obtd. by the reaction of epichlorohydrin and bisphenol IVA and has bisphenol A at least at one end. The electrostatic charge image developing toner is especially preferable when the resin having bisphenol A at least at one end is expressed by formula. In formula,(n)is 1-10. The resin having bisphenol A at least at one end is produced from epichlorohydrin and bisphenol A by the advance method which is usually used for the production of epoxy resin. Further, any coloring agent, mold release agent, antistatic agent, magnetic material, etc., may be used for the electrostatic charge image developing toner as far as the toner contains the resin above described as the binder resin.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to electrophotography, electrostatic recording,
The present invention relates to an electrostatic charge developing toner used for developing an electrostatic charge image in electrostatic printing or the like.

[0002]

2. Description of the Related Art In electrophotography, an electrostatic latent image is usually formed on a latent electrostatic image bearing member made of a photoconductive photosensitive member by charging and exposure, and then the electrostatic latent image is formed in a binder resin. It is a method of forming a visible image by developing with a toner composition containing a colorant and transferring and fixing the obtained toner image to a support such as transfer paper.

In a toner composition for obtaining such a visible image, a binder resin is generally used as a binder resin, and polystyrene, a styrene- (meth) acrylic acid ester copolymer is used as a binder resin, Styrene
Butadiene copolymer, polyester resin, epoxy resin, butyral resin, xylene resin, coumarone indene resin, etc. may be mentioned, but in the current copying machines, toner is used in order to lower the fixing temperature and improve the fixing strength. It is desired that the resin viscosity at the time of fixing is lower than that of the toner for general copying machine which has been conventionally used, and the glass transition temperature of the binder resin by differential thermal analysis is preferably 50 ° C. or higher. More preferably, the temperature is 55 ° C. or higher. If the glass transition temperature is too low, the toner tends to block. The glass transition temperature represents an endothermic peak temperature in differential thermal analysis. The melt viscosity of the binder resin measured by the flow tester method is 1 × 10 ⁴ to 1 × 10 ⁶ poise at 100 ° C.
Preferably, 3 × 10 ^{4 to} 5 × 10 ⁵ poise is suitable.
If the melt viscosity is too low, the offset resistance becomes poor, and if it is too high, good fixing strength cannot be obtained. However, the melt viscosity is based on Shimadzu's flow tester CFT-
Nozzle diameter 1 mm, load 30 kg, temperature rising rate 3
It is a value at 100 ° C measured under the condition of ° C / min.

As a colorant in a toner composition, a black colorant such as carbon black dispersed in a binder resin is often used. In recent years, a blue pigment,
Color toners in which a red pigment or a yellow pigment is dispersed in a binder are also used.

[0005]

However, with the progress of electrophotographic technology, the speed and color of the system have advanced, and in the toner using the binder resin system of the prior art, sufficient fixability and heat-resistant storage stability are obtained. Vivid color reproduction,
It is difficult to maintain both color transparency of the OHP film, and it is also difficult to stably maintain a visible image. Examples of binder resins that solve these problems include polyester resins and epoxy resins. That is, styrene resin, styrene-acrylic resin, styrene-
With the above-mentioned melt viscosity, the glass transition temperature of the butadiene-based resin and others is too low, and the toner blocking property is lowered, so that it cannot be put to practical use. However, in these polyester resins and epoxy resins, a large number of hydrophilic groups such as carboxyl groups and hydroxyl groups are present in the molecule, and therefore these resins have hygroscopicity as compared with polystyrene and styrene-acrylic copolymer resins. As a result, the charge quantity tends to fluctuate due to environmental changes, and in addition, in epoxy resins, the reactivity to heat is affected by the effect of the epoxy group, which is a characteristic of the structure. In some cases, the melt viscosity may increase in the heat-melting and kneading step of forming a toner, and a chemical effect on the photoconductor may occur.

The problem to be solved by the present invention is to provide a new resin system satisfying these characteristics.

[0007]

As a result of intensive studies to solve the above-mentioned problems, the present inventors have reached the development of a new resin system having a low melt viscosity and a high glass transition temperature.

In other words, in order to solve the above-mentioned problems, the present invention provides that at least one of the terminals obtained by reacting epichlorhydrin with bisphenol A is bisphenol A.
A toner for developing an electrostatic charge image, which comprises a resin represented by the general formula (1):

[0009]

[Chemical 2]

A toner for developing an electrostatic charge image, which is a resin represented by the formula (n represents 1 to 10), is provided.

Next, the present invention will be described in detail.

The resin represented by the general formula (I) in which at least one of the terminals is bisphenol A used in the present invention is produced from epichlorohydrin and bisphenol A. The manufacturing method at this time is an advance method generally used for manufacturing an epoxy resin. In this method, a low molecular weight epoxy resin is produced by reacting epichlorohydrin and bisphenol A by a usual method as a first step reaction, and a low molecular weight epoxy resin is added as a second step reaction to the low molecular weight epoxy resin.
Further, bisphenol A and a polymerization catalyst are added, and heat polymerization is carried out. In this method, as in the present invention,
In order to obtain a resin in which at least one of the terminals is bisphenol A, the amount of the phenolic hydroxyl group of bisphenol A used in the second step reaction is the epoxy equivalent of 1 equivalent of the low molecular weight epoxy resin obtained in the first step reaction. As opposed to
It is necessary to make it 1 equivalent or more. If the amount of this phenolic hydroxyl group is less than 1 equivalent, the terminal group of the obtained resin will be a glycidyl ether group, and a reaction product having bisphenol A at the target terminal cannot be obtained. On the other hand, if the amount of the phenolic hydroxyl group is too large, the molecular weight of the obtained reaction product becomes small, and the fixing property of the resulting toner tends to deteriorate, which is not preferable. Therefore, the amount of the phenolic hydroxyl group of bisphenol A used in the second-stage reaction is usually in the range of 1.01 to 3.5 equivalents per 1 equivalent of epoxy equivalent of the low molecular weight epoxy resin. As the polymerization catalyst in the second-stage reaction, a catalyst used in ordinary epoxy resin polymerization, for example, alkali metal hydroxides and salts thereof, tertiary amines, quaternary ammonium salts, imidazoles, phosphines , Phosphonium salts or mixtures thereof can be used.

The toner for electrostatic charge development of the present invention may contain the above-mentioned resin system as a binder resin, and the use of colorants, release agents, charge control agents, magnetic materials and other additives is limited. Not to receive.

That is, as the colorant, carbon black is generally used for the black toner, and depending on the case,
A blackened toner is used by appropriately selecting and mixing yellow dye / pigment, red dye / pigment, orange dye / pigment, brown dye / pigment, blue dye / pigment, and the like. Sometimes. Examples of these dyes and pigments include azo dyes and pigments, quinoline dyes and pigments, isoindoline dyes and pigments, tetrachloro-isoindolinone dyes and pigments, imidazolone dyes and pigments, anthraquinone dyes and pigments, xanthene dyes and pigments. Perylene dyes and pigments, quinacridone dyes and pigments,
Examples include phthalocyanine dyes and pigments.

Further, it can be sufficiently used for a color toner, and the colorant component in that case is not limited.
Examples of the colorant include azo dyes, anthraquinone dyes, phthalocyanine dyes, indigo dyes, thioindigo dyes, diphenylmethane dyes, triphenylmethane dyes, polymethine dyes, azomethine dyes, xanthene dyes, acridine dyes, quinoneimine dyes, cyanine dyes, and quinoline dyes. Dyes, nitro dyes, naphthoquinone dyes, perylene dyes, nitro pigments, nitroso pigments, acid dye lake pigments, basic dye lake pigments, mordant dye lake pigments,
Soluble azo pigment, insoluble azo pigment, azo complex salt pigment, condensed azo pigment, benzimidazolone pigment, phthalocyanine pigment, anthraquinone pigment, thioindigo pigment, perylene pigment, perinone pigment, quinacridone pigment, dioxane pigment, quinophthalone pigment, isoindolinone pigment, Examples thereof include metal complex salt pigments. The content of the colorant component is 1 with respect to 100 parts by weight of the binder resin constituting the toner.
The range of 10 to 10 parts by weight is preferable. If it is less than 1 part by weight, the hiding power tends to be insufficient, and a sufficient color density tends not to be obtained,
On the other hand, if the amount exceeds 10 parts by weight, unfavorable effects on the fixing properties and charging properties and effects such as impairing the color saturation tend to appear.

As the release agent, low molecular weight polyethylene,
Waxes such as low molecular weight polypropylene, liquid paraffin, fatty acid esters, fatty acid amides, and ethylene-vinyl acetate copolymers can be used.

Various charge control agents can be used in the toner of the present invention. Typical examples thereof include nigrosine dyes, triphenylmethane dyes, quaternary ammonium salt complexes and their derivatives, and various metals. Examples thereof include complex azo dyes, salicylic acid metal complexes, copper phthalocyanine sulfonylamines, and chlorinated paraffins.

Examples of the magnetic material include metal powders such as iron, manganese, nickel and cobalt, alloys, fine particles of oxides, iron alloys such as ferrite and magnetite, and other magnetic materials.

Further, in the toner of the present invention, for the purpose of improving the fluidity and the cleaning property of the toner, fine powder of an oxide such as silicon, titanium, aluminum or cerium which has been subjected to a hydrophobic treatment or a fatty acid metal salt. Fine powder or the like can be added.

To manufacture the toner, a binder resin,
The colorant, the charge control agent and the like are well mixed beforehand with a ball mill or the like, sufficiently melt-kneaded with various kneaders, cooled, and then finely pulverized with a jet mill or the like to classify to a desired particle size. If necessary, a fluidity improver and the like are added and mixed.

[0021]

EXAMPLES The present invention will be described in more detail below with reference to examples. In the examples, "part" means "part by weight".

Resin Production Example 1 Epichlorohydrin 450 was placed in a four-necked flask equipped with a thermometer, a stirrer and a heater.
Part and heat under a nitrogen stream to bring the temperature inside the flask to 7
The temperature was raised to 0 ° C., 0.48 parts of an aqueous sodium hydroxide solution was added as a catalyst, and the mixture was sufficiently stirred and then heated to 100 ° C.
Increase the temperature to, then bisphenol A51
After adding 5.16 parts and completely dissolving it, the reaction was carried out for 5 hours in a nitrogen atmosphere while maintaining the temperature at 160 ° C. to obtain a reaction product having bisphenol A at the terminal. The weight average molecular weight of this resin is 1,300, Tg is 70 ° C.,
The melt viscosity was 3 × 10 ⁴ poise.

Example 1 <Preparation of Toner> 93 parts of the resin obtained in the above Production Example 1 and carbon black “Elftex 8” (E
5 parts of "lftex8; Cabot Corporation" and "Bontron E-84" as a charge control agent (Orient Chemical Industry)
(Manufactured by K.K.) 2 parts by melt-kneading, and after cooling, finely pulverized by a jet mill and classified to obtain a toner having an average particle size of 11 μm (hereinafter,
It is referred to as "toner (1)". ) Was produced.

<Preparation of Developer> 4 parts of Toner (1) and "Ferrite Carrier F-150" (Powder Tech Co., Ltd.)
A developer was prepared by frictionally mixing 96 parts).

<Measurement of Charge Amount> The prepared developer was subjected to high temperature and high humidity (40 ° C., 90% RH), normal temperature and normal humidity (20 ° C., 50).
% RH) and low temperature and low humidity (10 ° C., 20% RH) were left for 1 hour in three different environments, and immediately after that, the charge amount was measured. The fluctuation range of charge amount due to environmental changes was calculated and evaluated. The results are shown in Table 1. In the table, HH is the high temperature and high humidity environmental conditions, MM is the normal temperature and normal temperature environmental conditions, LL is the low temperature and low humidity environmental conditions, and the environmental difference is the value obtained by subtracting HH from LL.

<Evaluation of storability> Obtained toner (1) 5
After weighing g in a 50 cm ³ glass bottle and leaving it in an atmosphere adjusted to 50 ° C. for 24 hours, the degree of aggregation was evaluated. The results are shown in Table 1.

<Evaluation of Toner Strength> The printed matter developed with the developer prepared using Toner (1) was evaluated for the strength of the melt-fixed toner against bending. The results are shown in Table 1.

(Resin Production Example 2) In resin production example 1,
A reaction product was obtained in the same manner as in Resin Production Example 1 except that 0.65 parts of an aqueous sodium hydroxide solution and 675 parts of bisphenol A were used. The weight average molecular weight of this resin is
1,800, Tg is 78 ° C., melt viscosity is 1 × 10 ⁵
It was a poise.

Example 2 <Preparation of Toner> Example 1 was repeated except that the resin obtained in Resin Production Example 1 was replaced with 93 parts of the resin obtained in Resin Production Example 2 in Example 1. In the same manner as
A toner of μm (hereinafter, referred to as “toner (2)”) was prepared.

<Preparation of Developer> A developer was prepared by frictionally mixing 4 parts of Toner (2) and 96 parts of "Ferrite Carrier F-150".

<Measurement of Charge Amount> The prepared developer was measured for charge amount in the same manner as in Example 1, and the variation range of charge amount due to environmental changes was calculated and evaluated. The results are shown in Table 1.

<Evaluation of storability> The toner (2) thus obtained was evaluated in the same manner as in Example 1 to evaluate the degree of aggregation. The results are shown in Table 1.

<Evaluation of Toner Strength> The printed matter developed with the developer prepared using Toner (2) was evaluated for the strength of the melt-fixed toner against bending. The results are shown in Table 1.

(Resin Production Example 3) In resin production example 1,
A reaction product was obtained in the same manner as in Resin Production Example 1 except that 0.79 parts of an aqueous sodium hydroxide solution and 810 parts of bisphenol A were used. The weight average molecular weight of this resin is
2,200, Tg 82 ° C, melt viscosity 5 × 10 ⁵
It was a poise.

Example 3 <Preparation of Toner> Example 1 was repeated except that the resin obtained in Resin Production Example 1 was replaced with 93 parts of the resin obtained in Resin Production Example 2 in Example 1. In the same manner as
A toner of μm (hereinafter referred to as “toner (3)”) was prepared.

<Preparation of Developer> A developer was prepared by frictionally mixing 4 parts of Toner (3) and 96 parts of “Ferrite Carrier F-150”.

<Measurement of Charge Amount> The charge amount of the prepared developer was measured in the same manner as in Example 1, and the fluctuation range of the charge amount due to environmental changes was calculated and evaluated. The results are shown in Table 1.

<Evaluation of storability> The toner (3) thus obtained was evaluated in the same manner as in Example 1 for the degree of aggregation. The results are shown in Table 1.

<Evaluation of Toner Strength> The printed matter developed with the developer prepared using Toner (3) was evaluated for the bending strength of the melt-fixed toner. The results are shown in Table 1.

Example 4 <Preparation of Toner> 95 parts of the resin obtained in the above Resin Production Example 1 and a copper phthalocyanine pigment “KET BL as a colorant.
3 parts of "UE 111" (manufactured by Dainippon Ink and Chemicals, Inc.) and 2 parts of "Bontron E-84" as a charge control agent were melt-kneaded, and after cooling, finely pulverized by a jet mill and classified to have an average particle diameter. A 11 μm toner (hereinafter referred to as “toner (4)”) was prepared.

<Preparation of Developer> 4 parts of Toner (4) and 96 parts of "Ferrite Carrier F-150" were frictionally mixed to prepare a developer.

<Measurement of Charge Amount> The developer thus prepared was measured for charge amount in the same manner as in Example 1 to calculate and evaluate the fluctuation range of charge amount due to environmental changes. The results are shown in Table 1.

<Evaluation of storability> The toner (4) obtained was evaluated in the same manner as in Example 1 to evaluate the degree of aggregation. The results are shown in Table 1.

<Evaluation of Toner Strength> The printed matter developed with the developer prepared using Toner (4) was evaluated for the bending strength of the melt-fixed toner. The results are shown in Table 1.

Comparative Example 1 <Preparation of Toner> Epoxy Resin “Epiclon 405”
0 ”(manufactured by Dainippon Ink and Chemicals, Inc., Tg: 65 ° C., weight average molecular weight: 4,500) and 93 parts and the same colorant and charge control agent as in Example 1 were used in the same manner as in Example 1. Toner (hereinafter referred to as "toner (5)") was prepared.

<Preparation of Developer> 4 parts of Toner (5) and 96 parts of "Ferrite Carrier F-150" were frictionally mixed to prepare a developer.

<Measurement of Charge Amount> The charge amount of the prepared developer was measured in the same manner as in Example 1 and the fluctuation range of the charge amount due to environmental changes was calculated and evaluated. The results are shown in Table 1.

<Evaluation of storability> The toner (5) obtained was evaluated in the same manner as in Example 1 to evaluate the degree of aggregation. The results are shown in Table 1.

<Evaluation of Toner Strength> The printed matter developed with the developer prepared using Toner (5) was evaluated for the strength of the melt-fixed toner against bending. The results are shown in Table 1.

Comparative Example 2 <Preparation of Toner> In Example 1, 64 parts of 2,2′-bis [p- (2-hydroxyethoxy) -phenyl] propane was used instead of the resin of Resin Production Example 1. Isophthalic acid 1
6 parts, terephthalic acid 16 parts, maleic anhydride 0.6 parts,
Polyester resin obtained by reacting 0.06 part of dibutyltin oxide (melt viscosity: 5 × 10 ⁴ poise, Tg:
A toner (hereinafter referred to as “toner (6)”) was produced in the same manner as in Example 1 except that 93 parts of 59 ° C. and weight average molecular weight of 10,000 were used.

<Preparation of Developer> 4 parts of Toner (6) and 96 parts of "Ferrite Carrier F-150" were frictionally mixed to prepare a developer.

<Measurement of Charge Amount> The developer thus prepared was measured for charge amount in the same manner as in Example 1, and the variation range of charge amount due to environmental changes was calculated and evaluated. The results are shown in Table 1.

<Evaluation of storability> The toner (6) thus obtained was evaluated in the same manner as in Example 1 for the degree of aggregation. The results are shown in Table 1.

<Evaluation of Toner Strength> The printed matter developed with the developer prepared using Toner (6) was evaluated for the strength of the melt-fixed toner against bending. The results are shown in Table 1.

Comparative Example 3 <Preparation of Toner> In Example 1, instead of the resin of Resin Production Example 1, a styrene / acrylic resin “Haimer SB” was used.
M-100 "(manufactured by Sanyo Kasei Co., Ltd., Tg: 54 ° C, weight average molecular weight: 13,000)" in the same manner as in Example 1 except that 93 parts were used. ]) Was produced.

<Preparation of Developer> A developer was prepared by frictionally mixing 4 parts of Toner (7) and 96 parts of “Ferrite Carrier F-150”.

<Measurement of Charge Amount> The prepared developer was measured for charge amount in the same manner as in Example 1, and the variation range of charge amount due to environmental changes was calculated and evaluated. The results are shown in Table 1.

<Evaluation of storability> The toner (7) obtained was evaluated in the same manner as in Example 1 to evaluate the degree of aggregation. The results are shown in Table 1.

<Evaluation of Toner Strength> The printed matter developed with the developer prepared using Toner (7) was evaluated for the strength of the melt-fixed toner against bending. The results are shown in Table 1.

[0060]

[Table 1]

[0061]

The toner using the resin system according to the present invention has a low melt viscosity and a high glass transition temperature,
Sufficient heat-resistant storage stability and sufficient fixing strength can be obtained.

Claims (2)

[Claims] 1. Epichlorhydrin and bispheno A
A toner for developing an electrostatic image, which comprises a resin having at least one of bisphenol A obtained by reacting with. 2. A compound represented by the general formula (1): The toner for developing an electrostatic charge image according to claim 1, containing a resin represented by the formula (n represents 1 to 10).