JPH11305479A - Full-color capsulated toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a full-color capsulated toner for heat pressure fixation excellent in transparency and excellent also in shelf stability and bending resistance. SOLUTION: The full-color capsulated toner consists of a heat-meltable core material contg. at least a vinyl polymer resin and a shell comprising a non- crystalline polyester or a hybrid resin disposed so as to coat the surface of the core material. The amt. of a THF-insoluble component in the capsulated toner is <=10 wt.% and the wt. average mol.wt. of a THF-soluble component is 15,000-150,000. The core material further contains liquid paraffin having 20-600 mm<2> /s kinematic viscosity at 37.78 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-pressure fixing full-color capsule toner used for developing an electrostatic latent image formed in electrophotography, electrostatic printing, electrostatic recording, and the like.

[0002]

2. Description of the Related Art In recent years, with the development of electrophotography, many studies and practical applications of full-color toners used in two-color color copying machines, full-color copying machines, and the like have been made. Full-color toner is used in full-color electrophotography, which requires multiple developments and the superposition of several different color toner layers on the same support, thus preventing the different color tone of the underlying toner layer. It must be a colored toner having no transparency.

In order to obtain excellent transparency, for example, a method of reducing the molecular weight of a resin (Fine Chemical, 1993, Vol.
22 , p. 7) is known, but when the resin is reduced in molecular weight, the image is peeled off from a fixing medium such as paper when the image after fixing is bent, or the storage stability is significantly reduced. Problems arise. Therefore, a full-color toner excellent in transparency, folding resistance, and storage stability has not been known.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a full-color capsule toner for heat and pressure fixing which is excellent in transparency, storage stability and bending resistance.

[0005]

SUMMARY OF THE INVENTION The gist of the present invention is to provide a heat-fusible core material containing at least a vinyl polymer resin and an amorphous polyester or hybrid provided so as to cover the surface of the heat-fusible core material. In a full-color capsule toner for heat and pressure fixing comprising a resin shell, the capsule toner has a tetrahydrofuran-insoluble content of 10% by weight or less, and a tetrahydrofuran-soluble component has a weight average molecular weight of 15,000 to 150,000. 20-600 mm ² / s at 37.78 ° C.
The present invention relates to a full-color capsule toner for heat and pressure fixing, characterized by containing a liquid paraffin having a kinematic viscosity of

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION A full-color capsule toner for heat and pressure fixing according to the present invention comprises a heat-fusible core material containing at least a vinyl polymer resin and an amorphous material provided so as to cover the surface of the heat-fusible core material. Is a full-color capsule toner for heat and pressure fixing comprising an outer shell made of porous polyester or a hybrid resin.

The raw material monomers for the vinyl polymer resin include, for example, styrene and styrene derivatives such as styrene and α-methylstyrene; for example, ethylenically unsaturated monoolefins such as ethylene and propylene; diolefins such as butadiene; Halovinyls such as vinyl chloride; vinyl esters such as vinyl acetate and vinyl propionate; ethylenic monocarboxylic acids such as (meth) acrylic acid; alkyl (1-18 carbon) esters of (meth) acrylic acid , (Meth) acrylic acid 2-
Hydroxyethyl, glycidyl (meth) acrylate,
Esters of ethylenic monocarboxylic acids such as dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate; vinyl ethers such as vinyl methyl ether; vinylidene halides such as vinylidene chloride; N-vinyl pyrrole; And N-vinyl compounds such as N-vinylpyrrolidone. Of these, styrene, ethylenically unsaturated monoolefins, ethylenic monocarboxylic acids and esters thereof are preferred.

In the present invention, from the viewpoint of controlling the thermal properties such as the softening point and the glass transition point of the resin, the styrene or styrene derivative forming the main skeleton of the resin is 50 to 50% in the monomer of the vinyl polymer resin. 90% by weight, and preferably 10 to 50% by weight of an ethylenic monocarboxylic acid or an ester thereof.

Examples of the polymerization initiator used for polymerizing the raw material monomer of the vinyl polymerization resin include known azo or diazo polymerization initiators and peroxide polymerization initiators. It is preferably 0.1 to 20 parts by weight based on 100 parts by weight of the raw material monomer of the vinyl polymer resin.

When polymerizing the raw material monomer of the vinyl polymer resin, if necessary, a known crosslinking agent, preferably divinylbenzene and polyethylene glycol di (meth)
Acrylate may be used, and the amount of the acrylate may be 0.0 to 100 parts by weight of the raw material monomer of the vinyl polymer resin.
It is preferably from 01 to 15 parts by weight.

In the present invention, the heat-meltable core material contains liquid paraffin efficiently and the liquid paraffin plasticizes only the core material efficiently, so that the transparency is maintained without impairing the storage stability. It is presumed to be improved.

The "liquid paraffin" used in the present specification is a mixture of liquid saturated hydrocarbons of extremely high purity, which belongs to a lubricating oil fraction in terms of boiling point, and is a chemically stable hydrocarbon. Active, non-polar saturated hydrocarbon. Specifically, it is a paraffinic hydrocarbon, a naphthenic hydrocarbon or an organic liquid mixture containing these as a main component. Incidentally, paraffinic hydrocarbons are aliphatic hydrocarbons having a molecular formula represented by C _n H _{2n + 2} , those having a linear structure or those having a branched structure, and naphthenic hydrocarbons. is a cyclic saturated hydrocarbon represented by C _n H _2n, usually those having a cyclic structure of 5 to 6 carbon atoms. These are generally obtained from a high-boiling fraction of petroleum through each refining process, and are usually commercially available as a mixture of a paraffinic hydrocarbon and a naphthenic hydrocarbon.

The kinematic viscosity of liquid paraffin at 37.78 ° C. is 20 to 600 mm ² / s, preferably 20 to 600 mm ² / s.
５００500 mm ² / s, more preferably 20-1
20 mm ² / s, particularly preferably 30 to 100 m
m ² / s. That is, from the viewpoint of storage stability, 20 m
m ² / s or more, preferably 30 mm ² / s or more;
From the viewpoint of transparency, 600 mm ² / s or less, preferably 500 mm ² / s or less, more preferably 120 mm ² / s.
s or less, particularly preferably 100 mm ² / s or less.
In the present invention, the kinematic viscosity of the liquid paraffin is determined according to JIS.
It can be measured according to a method according to K2283.

The liquid paraffin preferably used in the present invention includes, for example, “Moresco White P-380”,
Moresco White P-200, Moresco White P-100, Moresco White P-300, Moresco White P-260, Moresco White P-
150 (manufactured by Matsumura Oil Research Co., Ltd.), "White Rex 247", "White Rex 221"
Commercially available products such as "0" (above, manufactured by Mobil Oil Co., Ltd.) may be used, and these may be used as a mixture.

The content of the liquid paraffin is preferably 0.1 to 20 parts by weight, more preferably 1 to 15 parts by weight, based on 100 parts by weight of the vinyl polymer resin. That is,
In order to improve the transparency, the amount is preferably 0.1 part by weight or more, preferably 1 part by weight or more based on 100 parts by weight of the vinyl polymer resin. It is desirable that the amount be 20 parts by weight or less, preferably 15 parts by weight or less based on 100 parts by weight of the resin.

In the present invention, the heat-meltable core material may optionally contain additives as needed. Here, as an additive, a coloring agent, a charge control agent, a fluidity improver,
Cleanability improvers, conductive substances, extenders, reinforcing fillers such as fibrous substances, antioxidants, anti-aging agents, anti-offset agents and the like, and these may be used alone or as a mixture of two or more. You may. Further, in the present invention, the additive may be contained in the outer shell by kneading with the resin which becomes the outer shell.

As the colorant used in the present invention, all dyes and pigments used as conventional colorants for toners can be used. For example, carbon black, phthalocyanine blue, permanent brown FG,
Brilliant First Scarlet, Pigment Green B, Rhodamine-B Base, Solvent Red 49,
Solvent Red 146, Solvent Blue 35, Quinacridone, Carmine 6B, Disazo Yellow and the like, and these can be used alone or in combination of two or more. The amount of the colorant used is preferably about 2 to 25 parts by weight based on 100 parts by weight of the vinyl polymer resin.

The outer shell of the capsule toner of the present invention comprises an amorphous polyester or a hybrid resin.

The amorphous polyester used in the present invention can be produced, for example, by using the compounds described in JP-A-7-175260 and by referring to the method described therein. In the present invention, the term "amorphous polyester" refers to a polyester having no clear melting point, and in particular, a polyester having a difference between a softening point and a glass transition point of 10C or more, preferably 20C or more.

In the above method, the starting monomer for the amorphous polyester may be a divalent or trivalent or higher alcohol component and a carboxylic acid such as a divalent or trivalent or higher carboxylic acid, carboxylic anhydride, or carboxylic ester. Ingredients are used.

As the dihydric alcohol component, for example,
Polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, polyoxyethylene (2.2)-
Examples include alkylene oxide adducts of bisphenol A such as 2,2-bis (4-hydroxyphenyl) propane, ethylene glycol, propylene glycol, 1,6-hexanediol, bisphenol A, and hydrogenated bisphenol A.

Examples of the trihydric or higher alcohol component include sorbitol, 1,4-sorbitan, pentaerythritol, glycerol, trimethylolpropane and the like.

Examples of the divalent carboxylic acid component include various dicarboxylic acids, succinic acid substituted with an alkyl group having 1 to 20 carbon atoms or alkenyl group having 2 to 20 carbon atoms, anhydrides of these acids, and alkyl groups. (C1-C12) ester etc. are mentioned. Among these, maleic acid, fumaric acid, terephthalic acid, and succinic acid substituted with an alkenyl group having 2 to 20 carbon atoms are preferable.

Examples of the trivalent or higher carboxylic acid component include 1,2,4-benzenetricarboxylic acid (trimellitic acid)
And acid anhydrides and alkyl (C1 to C12) esters thereof.

It is preferable to use a monomer having a benzene skeleton as a part of the raw material monomer from the viewpoint of improving the amorphous property.

When the raw material monomer of the amorphous polyester is polymerized, a commonly used esterification catalyst such as dibutyltin oxide may be appropriately used to accelerate the reaction.

In the present invention, the hybrid resin is
As described in JP-A-8-171231, it is obtained by mixing a mixture of two monomer monomers of a polymerization system each having an independent reaction path, and performing two polymerization reactions in the same reaction vessel. It is something that can be done.

In the present invention, the two polymerization reactions are carried out mainly by independent reaction paths, and are preferably reactions that produce a condensation polymerization resin and an addition polymerization resin, respectively. Representative examples of the condensation polymerization resin include polyester, polyester / polyamide, polyamide, and the like, and typical examples of the addition polymerization resin include:
Examples include a vinyl polymer resin obtained by a radical polymerization reaction.

Among these, the polyester component is obtained by using a divalent or trivalent or higher alcohol component and a divalent or trivalent or higher carboxylic acid, carboxylic anhydride or carboxylic acid ester as a raw material monomer. be able to.

As the alcohol component and the carboxylic acid component, those similar to those exemplified as the alcohol component and the carboxylic acid component of the amorphous polyester can be used.

The raw material monomer used for forming the polyester polyamide obtained by the polycondensation reaction or the amide component in the polyamide includes various known polyamines, aminocarboxylic acids, amino alcohols and the like. Diamine and ε-caprolactam.

As the raw material monomer used to form the vinyl polymer resin obtained by the addition polymerization reaction, for example, the monomers exemplified as the raw material monomer of the vinyl polymer resin contained in the heat-meltable core material may be used. it can.

The hybrid resin is prepared, for example, by mixing a raw material monomer of a polycondensation resin, a raw material monomer of an addition polymerization resin, a polymerization initiator, and the like. To obtain an addition-polymerized resin component having various functional groups,
After the reaction temperature is increased, the condensation polymerization resin component is preferably formed mainly by the condensation polymerization reaction. By such a method of allowing two independent reactions to proceed in one reaction vessel, a resin in which the compatibility of the two resins is improved can be effectively obtained.

In the present invention, the weight ratio of the condensation polymerization resin to the addition polymerization resin, that is, the weight ratio of the raw material monomer of the condensation polymerization resin to the raw material monomer of the addition polymerization resin is determined by the dispersibility of the addition polymerization resin. From a viewpoint, usually 50/5
It is desirably 0 to 95/5, preferably 60/40 to 95/5.

The hybrid resin can react with any of the raw material monomers of the two polymerization resins, for example, compounds such as acrylic acid, fumaric acid, methacrylic acid, citraconic acid, and maleic acid (hereinafter referred to as bireactive compounds). Can further improve the dispersibility of the resin.

In the capsule toner of the present invention, the softening point of the amorphous polyester and the hybrid resin is preferably from 90 to 140 ° C. from the viewpoint of high-temperature offset property, storage stability, stress resistance and low-temperature fixability. .

The glass transition point of the amorphous polyester and the hybrid resin is preferably from 50 to 80 ° C. from the viewpoint of storage stability and fixability of the toner.

The acid value of the amorphous polyester and the hybrid resin is preferably 1 to 30 (KOH mg / g) from the viewpoints of storage stability and production stability of the toner.

Since the amorphous polyester and the hybrid resin require an outer shell having an appropriate thickness in order to obtain blocking resistance and heat melting property, 3 to 100 parts by weight of the vinyl polymer resin is used. It is preferable to use about 20 parts by weight.

The full-color capsule toner for heat and pressure fixing according to the present invention has the following advantages in terms of simplification of manufacturing equipment and manufacturing steps.
It is preferable to produce by an in situ polymerization method.
The in situ polymerization method of the present invention is disclosed in
This is the same as the polymerization method disclosed in detail in JP-A-17925, JP-A-7-175260, JP-A-9-15900 and the like.

That is, in the in situ polymerization method,
Due to the difference in solubility index between the amorphous polyester or hybrid resin as the outer shell and the raw monomer of the vinyl polymer resin, the raw monomer of the vinyl polymer resin as the core material in the droplets of the mixed solution, and the outer shell Separation of the resin occurs, and in this state, the polymerization of the raw material monomer of the vinyl polymer resin proceeds to form a capsule structure.

In the present invention, the liquid paraffin can be contained in the core material by being added to the aqueous dispersion medium together with the raw material monomer of the vinyl polymer resin, the amorphous polyester or the hybrid resin. The amount of the liquid paraffin to be used is about 0.1 to 20 parts by weight, preferably 1 to 15 parts by weight, based on 100 parts by weight of the raw material monomer of the vinyl polymer resin.

The content of tetrahydrofuran insoluble in the full-color capsule toner for heat and pressure fixing of the present invention is 10% by weight or less, preferably 8% by weight or less from the viewpoint of transparency.

The weight average molecular weight of the tetrahydrofuran-soluble component of the full-color capsule toner for heat and pressure fixing of the present invention is from 15,000 to 150,000, preferably from 20,000 to 120,000, and more preferably from 4 to 120,000.
000 to 100,000. That is, from the viewpoint of bending resistance, it is 15,000 or more, preferably 20,000 or more, more preferably 40,000 or more, and from the viewpoint of transparency, 150,000 or less, preferably 12,000 or less.
0 or less, more preferably 100000 or less.

The glass transition point of the full-color capsule toner for heat and pressure fixing of the present invention derived from the vinyl polymer resin contained in the core material is preferably from 15 to 60 ° C., and more preferably from 20 to 50 ° C. That is, in order to maintain the storage stability of the capsule toner, the temperature is 15 ° C. or higher, preferably 2 ° C.
The temperature is desirably 0 ° C. or higher, and desirably 60 ° C. or lower, preferably 50 ° C. or lower in order to maintain the fixing strength of the capsule toner. The glass transition point can be adjusted, for example, by appropriately selecting the type of the raw material monomer. In the present invention, the vinyl polymer-based resin contained in the core material contains liquid paraffin, and the glass transition point means a value in a state containing liquid paraffin.

The softening point of the full-color capsule toner for heat and pressure fixing of the present invention is 70 to 160 ° C., and the average particle diameter is usually 3
It is preferably about 30 μm.

The full-color capsule toner for heat and pressure fixing of the present invention can be used as a non-magnetic one-component developer or as a two-component developer by mixing with a carrier.

The full-color capsule toner for heat and pressure fixing according to the present invention is disclosed in, for example, JP-A-2-190870 and JP-A-2-190870.
As described in JP-A-162356 or the like, by fixing heat and pressure together on a recording material such as paper, it is possible to give a good fixing strength to an image formed.

[0049]

EXAMPLES The softening point, glass transition point, acid value, kinematic viscosity, tetrahydrofuran insoluble matter and tetrahydrofuran soluble matter weight average molecular weights described in the examples are measured by the following methods.

[Softening point] Koka type flow tester (Co., Ltd.)
Using CFT-500 (manufactured by Shimadzu Corporation), the temperature at which half of the resin flows out is taken as the softening point (sample: 1 g, heating rate:
6 ° C / min, load: 20kg / cm ² , nozzle: 1mmφ
× 1 mm).

[Glass Transition Point] The glass transition point is measured at a heating rate of 10 ° C./min using a differential scanning calorimeter (DSC210, manufactured by Seiko Instruments Inc.).

[Acid value] It is measured according to a method according to JIS K0070.

[Kinematic viscosity] Measured according to a method according to JIS K2283.

[Tetrahydrofuran-insoluble matter]
The measurement is carried out in the same manner as “chloroform-insoluble matter measurement” described on page 11 of JP-A-547553. That is, 5.0 g of the toner, 5.0 g of radiolite and 100 g of tetrahydrofuran are stirred at room temperature for 5 hours or more to sufficiently dissolve the toner. Next, a filter paper (N) having a diameter of 7 cm, which was uniformly pre-coated with 5.0 g of radiolite, was placed in a pressure filter.
o. 2) is placed, the solution obtained by the above operation is poured into a pressure filter, and pressure filtration (about 4 kg / cm ² ) is performed. After the filtration is completed, the filter paper and the residue on the filter paper are removed at 80 ° C. and 100 mm
After drying for 10 hours under the condition of Hg, tetrahydrofuran insoluble matter is calculated.

[Weight average molecular weight of tetrahydrofuran-soluble component] Measured by gel permeation chromatography (sample concentration: 0.5% by weight, eluent: tetrahydrofuran, flow rate: 1 ml / min, temperature: 40 ° C., column: GMH
LX / G3000HXL (manufactured by Tosoh Corporation), standard sample: monodisperse polystyrene).

Resin Production Example 1 (Production of Amorphous Polyester) Polyoxypropylene (2.2) -2,2-bis (4-
550 g of hydroxyphenyl) propane, 180 g of polyoxyethylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, 337 g of terephthalic acid, 8.0 g of trimellitic anhydride, and 2.0 g of dibutyltin oxide
Is reacted at 220 ° C. under a nitrogen atmosphere, and the softening point (A
The reaction was terminated when STM E28-67) reached 118 ° C. The obtained resin is referred to as resin A. Resin A had a softening point of 120.1 ° C., a glass transition point of 72 ° C., and an acid value of 8 (KOH mg / g).

Resin Production Example 2 (Production of Hybrid Resin) Styrene 49 was used as a raw material monomer of the vinyl polymer resin.
0 g, 2-ethylhexyl acrylate 73 g, acrylic acid 25 g as a bi-reactive compound, and ditertiary butyl peroxide 22 g as a polymerization initiator were placed in a dropping funnel. As raw material monomers for polyester, 1425 g of polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane and polyoxyethylene (2.2) -2,2-bis (4-hydroxyphenyl) propane 273 g, 790 g of terephthalic acid, and 5 g of dibutyltin oxide as an esterification catalyst were placed in a 5 liter four-necked flask, and stirred at 160 ° C. under a nitrogen atmosphere, and the starting monomer of the vinyl polymer resin was dropped from the dropping funnel, The bi-reactive compound and the polymerization initiator were added dropwise over 1 hour. After aging the addition polymerization reaction for 2 hours while maintaining the temperature at 160 ° C., the temperature was raised to 230 ° C. to cause the condensation polymerization reaction, and the reaction was terminated when the softening point reached 110 ° C. in the same manner as described above. I let it. The obtained resin is referred to as resin B. Resin B had a softening point of 111.6 ° C., a glass transition point of one peak at 65.2 ° C., and an acid value of 11 (KOH mg / g).

Example 1 Resin A 75 parts by weight, magenta pigment "Hostaperm Pink EB"
(Manufactured by Hoechst) 25 parts by weight using a Henschel mixer, kneading using a twin-screw extruder equipped with a barrel cooling device, cooling the obtained kneaded material, and kneading by pulverizing. The product A was obtained.

75 parts by weight of styrene, 25 parts by weight of 2-ethylhexyl acrylate and 20 parts by weight of kneaded material A, liquid paraffin "Moresco White P-380" [mixture of paraffinic hydrocarbon and naphthenic hydrocarbon (paraffinic hydrocarbon) : Naphthenic hydrocarbon = 7: 3 (weight ratio), kinematic viscosity at 37.78 ° C. is 83.32 mm.
² / s, manufactured by Matsumura Oil Laboratory Co., Ltd.] 6 parts by weight and 2,
3.5 parts by weight of 2′-azobisisobutyronitrile were mixed in a beaker, and the mixture was stirred using a magnetic stirrer for 2 hours to obtain 240 g of a polymerizable composition. Then, an aqueous colloid solution 56% of 4% by weight of tricalcium phosphate previously prepared was placed in a 2-liter glass separable flask.
0 g, the polymerizable composition 240 g was added. K.
15 ° C using a homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.)
And emulsified and dispersed at 12,000 rpm for 5 minutes.

Next, a four-necked glass lid was fitted, a reflux condenser, a thermometer, a nitrogen inlet tube, and a stainless steel stirrer were attached, and the flask was set on a mantle heater. While stirring the mixture under a nitrogen atmosphere, the temperature was raised to 70 ° C., and the polymerization reaction was performed for 5 hours. Then, the reaction was further performed at 95 ° C. for 5 hours.
After cooling, a 10% by weight aqueous hydrochloric acid solution was added to dissolve the dispersion stabilizer, followed by filtration and washing with water.
The capsule toner was dried under reduced pressure at 0 mmHg and classified using an air classifier to obtain a capsule toner having an average particle diameter of 8 μm.

To 100 parts by weight of the encapsulated toner, 0.4 parts by weight of hydrophobic silica fine powder "Aerosil silica R-972" (manufactured by Nippon Aerosil Co., Ltd.) is added and mixed to give a surface treatment to the encapsulated toner. To obtain a toner 1.

Example 2 In Example 1, the amount of 2,2'-azobisisobutyronitrile used was changed from 3.5 parts by weight to 2 parts by weight, and styrene and 2-ethylhexyl acrylate were used together with divinyl. Surface treatment was performed in the same manner as in Example 1 except that 0.2 parts by weight of benzene was used, to obtain Toner 2.

Example 3 In Example 1, resin B was used instead of resin A75 parts by weight.
Surface treatment was carried out in the same manner as in Example 1 except that 75 parts by weight was used, to obtain Toner 3.

Example 4 In Example 2, “Moresco White P-260” [a mixture of paraffinic and naphthenic hydrocarbons, 37 A kinematic viscosity at 78 ° C. of 5
5.2 mm ² / s, manufactured by Matsumura Oil Laboratory Co., Ltd.] The same procedure as in Example 2 was carried out except that 6 parts by weight was used, to obtain a toner 4.

Example 5 In Example 2, "Moresco White P-150" [a mixture of paraffinic and naphthenic hydrocarbons, 37 A kinematic viscosity at 78 ° C. of 3
2.9 mm ² / s, manufactured by Matsumura Oil Laboratory Co., Ltd.] Toner 5 was obtained in the same manner as in Example 2 except that 6 parts by weight was used.

Example 6 In Example 2, "Moresco White P-380" was used together with "Moresco White P-380" as liquid paraffin.
150 "[kinematic viscosity at 37.78 ° C. is 32.9 mm
² / s, manufactured by Matsumura Oil Laboratory Co., Ltd.] The same procedure as in Example 2 was carried out except that 3 parts by weight was used, to obtain a toner 6.

Example 7 In Example 1, “White Rex 2210” [having a kinematic viscosity at 37.78 ° C. of 45 was used instead of 6 parts by weight of “Moresco White P-380” as a liquid paraffin.
4 mm ² / s, manufactured by Mobile Oil Co., Ltd.] except that 6 parts by weight were used, and the same procedure as in Example 1 was performed until surface treatment.
Toner 7 was obtained.

Comparative Example 1 The procedure of Example 1 was repeated except that 6 parts by weight of liquid paraffin “Moresco White P-380” was not used.
By performing the same operations up to the surface treatment, Comparative Toner 1 was obtained.

Comparative Example 2 In Example 1, 6 parts by weight of liquid paraffin “Moresco White P-380” was not used, and the amount of 2,2′-azobisisobutyronitrile was changed from 3.5 parts by weight. After changing the polymerization reaction temperature to 70 ° C. and performing the reaction for 5 hours, the temperature was raised to 85 ° C. for 5 hours, and then the reaction temperature was further increased to 95 ° C. for 5 hours. A surface treatment was carried out in the same manner as in Example 1 except that the operation was carried out to obtain Comparative Toner 2.

Comparative Example 3 In Example 1, “Moresco White P-55” (a kinematic viscosity at 37.78 ° C. of 9.9) was used instead of 6 parts by weight of “Moresco White P-380” as a liquid paraffin.
Comparative toner 3 was obtained in the same manner as in Example 1, except that 85 mm ² / s and 6 parts by weight (manufactured by Matsumura Oil Research Laboratory Co., Ltd.) were used.

Comparative Example 4 A comparative toner 4 was obtained in the same manner as in Example 1, except that 0.8 parts by weight of divinylbenzene was used together with styrene and 2-ethylhexyl acrylate. Was.

The softening point (Tm) of the toner obtained by the above method, the glass transition point (Tg) derived from the vinyl polymer resin in the core material, the tetrahydrofuran-insoluble component (THF-insoluble component) and the tetrahydrofuran-soluble component Table 1 shows the weight average molecular weight (Mw).

[0073]

[Table 1]

Test Example 1 6 parts by weight of each of toners 1 to 7 and comparative toners 1 to 4
Spherical ferrite powder 94 coated with a styrene-methyl methacrylate resin having a particle size of 50 to 400 mesh
Parts by weight and placed in a plastic container.
The container was rotated and mixed on a roller for 0 minutes to prepare a developer.

Using the obtained developer, the transparency and folding resistance of the toner were evaluated according to the following methods. Table 2 shows the results.

(1) Transparency of Toner Using a commercially available full-color copying machine (in which the surface temperature of an oil coating type fixing device is made variable), the developing bias voltage is adjusted on the OHP sheet to adjust the toner adhesion amount ( 0.5mg
/ Cm ² ) is constant. The transparency is evaluated by measuring the transmittance of the obtained image at 480 nm using a spectral colorimeter (SZ- # 80, manufactured by Nippon Denshoku Industries Co., Ltd.). The fixing temperature is adjusted to 160 ° C.

(2) Bending resistance Using a full-color copying machine similar to that used in the evaluation of the transparency of the toner, the developing bias voltage was adjusted so that the toner adhesion amount was 0.5 mg / cm ^2. After the image is formed on paper and fixed at 160 ° C., the same operation is repeated on the same paper. That is, the adhesion amount of the toner is twice the evaluation of the transparency, and two toner layers are fixed. Next, the solid image portion of the paper is folded in two, the peeling state of the obtained image is observed according to the following evaluation criteria, and the bending resistance is evaluated.

[Evaluation Criteria] A: Almost no peeling X: Remarkable peeling

Test Example 2 10 g of each of toners 1 to 7 and comparative toners 1 to 4
The sample was precisely weighed, placed in a glass container, sealed, and left for 48 hours in a thermostat in which the temperature in the vessel was adjusted to 50 ° C. The aggregation degree of the toner after standing was determined according to the method described below, and the storage stability was evaluated. Table 2 shows the results.

[Agglomeration degree] Using a powder tester manufactured by Hosokawa Micron Co., Ltd., each had a diameter of 70 mm and a sieve of 250 μm (sieve 1), 14
A sieve of 9 μm (Sieve 2) and a sieve of 74 μm (Sieve 3) are set, and 2 g of toner is placed on the sieve. Vibration having an amplitude of 1 mm is applied for 1 minute to perform measurement, and the amount of toner remaining on each sieve (% by weight) ) Is calculated, and the degree of aggregation is calculated by the following equation. Cohesion (%) = (Sieve 1) ^* x 1 + (Sieve 2) ^* x
0.6+ (Sieve 3) ^* × 0.2 * Amount of toner remaining on each sieve (% by weight)

[0081]

[Table 2]

From the results shown in Table 2, it can be seen that the toners 1 to 7 obtained in the examples have excellent transparency, bending resistance and storage stability. On the other hand, Comparative Toner 1 lacked transparency because liquid paraffin was not added.
It can be seen that, since the resin having a reduced molecular weight is used as the core resin, the bending resistance is extremely poor.
Further, it can be seen that the comparative toner 3 has a very low storage stability due to the use of low-viscosity liquid paraffin, and the comparative toner 4 is inferior in transparency due to a large amount of tetrahydrofuran insoluble matter.

[0083]

According to the present invention, it is possible to provide a full-color capsule toner for heat and pressure fixing which is excellent in transparency, storage stability and folding resistance.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI G03G 9/08 365

Claims (3)

[Claims] 1. A heat-fusible core material containing at least a vinyl polymer resin and an outer shell made of an amorphous polyester or hybrid resin provided so as to cover the surface of the heat-fusible core material. In the full-color capsule toner for heat and pressure fixing, the tetrahydrofuran-insoluble content of the capsule toner is 10% by weight or less, and the weight average molecular weight of the tetrahydrofuran-soluble component is 15,000 to 15,000.
0 at 37.78 ° C.
A full-color capsule toner for heat and pressure fixing, comprising liquid paraffin having a kinematic viscosity of 0 to 600 mm ² / s. 2. The liquid paraffin is a vinyl polymer resin 10
2. The full-color capsule toner for heat and pressure fixing according to claim 1, which is contained in an amount of 0.1 to 20 parts by weight based on 0 part by weight. 3. The full-color capsule toner for heat and pressure fixing according to claim 1, wherein the glass transition point of the capsule toner derived from the vinyl polymer resin is 15 to 60 ° C.