JPH06317925A - Thermocompression fixing capsule toner and its production - Google Patents

Abstract

PURPOSE:To improve the offset resistance and storage stability and to make possible low temp. fixing by adding vinyl polymerizable monomers and vinyl polymn. initiator to a water-base suspension of precursor particles whose core surface is coated with a hydrophilic shell material and polymetizing the monomer component in the precursor particles. CONSTITUTION:Precursor particles are obtd. by coating the core surface by in-situ polymn. with a hydrophilic shell material, for example, a shell material containing amorphous polyester as the main component (reaction in the first stage). At least a vinyl polymerizable monomer and a vinyl polymn. initiator are added to a water-base suspension of the precursor particles so that the monomer and initiator are absorbed in the precursor particles. Then, the monomer component in precursor particles is polymerized by seed polymn. method (reaction in the second stage). Namely, a polymerizable compsn. is prepared by mixing 69 pts.wt. of styrene, 31 pts.wt. of 2- ethylhexylacrylate, etc., and heated to effect the reaction for the first polymn. to obtain the precursor as seed particles. Then 13 pts.wt. of styrene is added to the water-base suspension of the precursor and the second polymn. is performed to obtain the capsule toner.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a heat and pressure fixing capsule toner used for developing an electrostatic latent image formed in electrophotography, electrostatic printing, electrostatic recording, etc.
And a heat and pressure fixing capsule toner obtained by the method.

[0002]

2. Description of the Related Art Conventional electrophotographic methods include US Pat. Nos. 2,297,691 and 235780.
As described in, for example, No. 9, the photoconductive insulating layer is uniformly charged, and then the layer is exposed to light to dissipate the charge on the exposed portion to form an electrical latent image. After being formed, and further visualized by adhering a fine powder having a colored charge called a toner to the latent image (developing step), after transferring the obtained visible image to a transfer material such as transfer paper (Transfer step), permanent fixing by heating, pressure or other suitable fixing method (fixing step). As described above, the toner must have the functions required not only in the developing step but also in the transfer step and the fixing step.

Generally, toner is subjected to a mechanical frictional force due to a shearing force and an impact force received during mechanical operation in a developing device,
It deteriorates during the copying of thousands to tens of thousands of sheets. To prevent such toner deterioration, a tough resin having a large molecular weight that can withstand mechanical friction may be used, but these resins generally have a high softening point and are a non-contact fixing method such as oven fixing and infrared fixing. In the radiant fixing method, the heat efficiency is poor and therefore the fixing is not sufficiently performed.Also, in the heat pressure fixing method which is widely used because the heat efficiency is good in the contact fixing method, it is necessary to fix the heat roller It is necessary to raise the temperature, which not only causes deterioration of the fixing device, curling of the paper, increase of energy consumption, etc., but also when such a resin is used, the pulverizability is poor,
When manufacturing a toner, the manufacturing efficiency is significantly reduced. Therefore, a binder resin having a too high degree of polymerization and a softening point cannot be used.

On the other hand, the heat pressure fixing method using a heat roller or the like has remarkably good thermal efficiency because the surface of the heat roller and the toner image surface of the sheet to be fixed are in pressure contact, and is widely used from low speed to high speed. When the surface and the toner image surface come into contact with each other, the toner tends to adhere to the surface of the heating roller and transferred to the subsequent transfer paper or the like, so-called offset phenomenon occurs. In order to prevent this phenomenon, the surface of the heating roller is processed with a material having an excellent releasing property such as a fluororesin, and a releasing agent such as silicone oil is applied to the surface of the heating roller to deal with the problem. However, the method of applying silicone oil or the like is not preferable because it easily causes a trouble because the fixing device becomes large and the cost becomes high, and it becomes complicated. Further, as described in JP-B-57-493, JP-A-50-44836, and JP-A-57-37353, there is a method of improving the offset phenomenon by asymmetrically or cross-linking the resin, but there is a fixing point. Has not been improved.

Generally, since the minimum fixing temperature is between the low temperature offset and the high temperature offset, the usable temperature range is between the minimum fixing temperature and the high temperature offset, and the minimum fixing temperature should be lowered as much as possible and the high temperature offset generation temperature should be as high as possible. By raising the temperature, the fixing temperature can be lowered and the usable temperature range can be widened, energy saving, high speed fixing and paper curl can be prevented. Therefore, there is always a demand for a toner having good fixability and offset resistance.

Conventionally, there has been proposed a technique for attaining low-temperature fixability by using a capsule toner composed of a core material and an outer shell provided so as to cover the surface of the core material as the toner. . Among them, when a low melting point wax that is easily plastically deformed is used as the core material (US Pat. No. 3,
269,626, Japanese Patent Publication No. 46-15876, Japanese Patent Publication No. 44-9880,
JP-A-48-75032 and JP-A-48-75033), fixing is possible only by pressure, but the fixing strength is poor and it can be used only in limited applications. Also, when a liquid core material is used, if the strength of the shell material is low, fixing can be done only by pressure, but it may crack inside the developing device and stain the inside of the machine. It takes a lot of pressure to break, resulting in images that are too glossy,
It was difficult to adjust the strength of the shell material.

Therefore, when used alone as a core material for heat and pressure fixing, blocking occurs at high temperatures, but a resin having a low glass transition point which improves the fixing strength is used, and blocking resistance and the like are provided as an outer shell. For this purpose, a heat roller fixing capsule toner in which a resin wall having a high melting point is formed by interfacial polymerization has been devised. However, in JP-A-61-56352, the wall material has a high melting point,
Furthermore, since it is tough and hard to crack, the performance of the core material has not been fully achieved. Further, a heat roller fixing capsule toner having an improved fixing strength of a core material has been proposed in the same way (Japanese Patent Laid-Open Nos. 58-205162 and 58-2051).
63 publication, 63-128357 publication, 63-128358 publication,
63-128359, 63-128360, and 63-1283.
No. 61, 63-128362), the manufacturing method is a spray-drying method, which imposes a burden on the manufacturing equipment, and the shell material has not been devised so that the performance of the core material has not been fully drawn out. . Further, in the capsule toner proposed in JP-A-63-281168, it is described that the shell material is thermotropic liquid crystal polyester, and in the capsule toner proposed in JP-A-4-184358, the crystalline property is Although polyester is used, the polyester melts sharply because the polyester is not amorphous, but the amount of energy required for melting is large, and the Tg of the core material is high, so the fixability is poor. In addition, Japanese Examined Patent Publication No.
The toner manufacturing methods proposed in JP-A 2-41748 and JP-A 3-35660 use seed polymerization, but when a material having a low glass transition point is used as the core material, the precursor particles are encapsulated. Therefore, the storage stability of the obtained toner was poor.

On the other hand, there is an attempt to control the chargeability of the capsule toner by allowing a charge control agent to exist in the outer shell of the capsule toner or on the surface of the capsule toner. For example, the toner is charged by friction with the carrier during the developing process. The control agent is detached and adheres to the carrier, the charge amount of the toner is reduced, and as a result, scumming and toner contamination in the machine occur.
There was a problem. Further, when the charge control agent is not present on the surface of the toner, the charging speed may be slow depending on the type of carrier, and when high speed printing is performed, scumming may occur.
Toner scattering and the like sometimes occurred.

The present invention has been made under the circumstances described above, and its purpose is to provide excellent offset resistance in a heat pressure fixing system such as a heat roller, which can be fixed at a low temperature, and has an anti-blocking property. It is an object of the present invention to provide a method for producing a heat and pressure fixing capsule toner having excellent properties, and a heat and pressure fixing capsule toner obtained by the method.

[0010]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found that the amount of a crosslinking agent used in the preparation of a core material should be improved offset resistance and fixability. By adjusting the Tg of the resin component of the core material and the presence of a hydrophilic outer shell material such as an amorphous polyester resin on the surface of the capsule toner, a clear image without background stain can be stably formed many times. I found that I could do it. That is, by controlling the distribution of the low molecular weight component and the high molecular weight component in the toner and by using a shell material composition with good blocking resistance, it is excellent in offset resistance in a heat pressure fixing method such as a heat roll. It was found that a capsule toner for heat and pressure fixing which can be fixed at a low temperature and has good storage stability is obtained, and the present invention has been completed.

That is, the gist of the present invention is: (1) a heat-melting core material containing at least a thermoplastic resin and a colorant, and a heat shell formed so as to cover the surface of the core material. In a method for producing a pressure-fixing capsule toner, a hydrophilic outer shell material is coated on the surface of a core material to give precursor particles, and then an aqueous suspension of the precursor particles is subjected to at least vinyl-polymerizable monomer and vinyl-polymerization initiation. A method for producing a capsule toner for heat-and-pressure fixing, which comprises adding an agent to the precursor particles to absorb them, and then polymerizing a monomer component in the precursor particles, and (2) at least thermoplasticity In a heat and pressure fixing capsule toner composed of a heat-meltable core material containing a resin and a colorant, and an outer shell provided so as to cover the surface of the core material, a hydrophilic outer shell material is provided on the surface of the core material. Coat to precursor particles, then At least a vinyl-polymerizable monomer and a vinyl polymerization initiator are added to an aqueous suspension of the precursor particles and absorbed in the precursor particles, and then the monomer components in the precursor particles are polymerized. The present invention relates to a capsule toner for heat and pressure fixing, which is obtained.

The method for producing the capsule toner for heat and pressure fixing of the present invention is produced by a two-step polymerization reaction of a first-step reaction and a second-step reaction. That is, in the production method of the present invention, a shell material containing, for example, an amorphous polyester as a main component as a hydrophilic outer shell material is coated on the surface of the core material by an in situ polymerization method to form a precursor particle (first step reaction). ), At least a vinyl-polymerizable monomer and a vinyl polymerization initiator are added to an aqueous suspension of the precursor particles so that they are absorbed in the precursor particles, and then a unit amount in the precursor particles is obtained by a seed polymerization method. It is preferable to polymerize the body component (second step reaction). Here, the term “precursor particles” means polymerization of the monomer component of the present invention (second stage reaction)
Particles used as the precursor of the capsule toner, which may be referred to as encapsulated particles in the present specification.

First, the precursor particles used in the present invention will be described. The core material of the precursor particles in the present invention is a core material of the capsule toner of the present invention, and is therefore a heat-meltable core material containing at least a thermoplastic resin and a colorant. The resin component of the core material in the precursor particles may be one in which a cross-linking structure was formed by using a cross-linking agent in the preparation as described below, or prepared without adding the cross-linking agent. It may be one. The precursor particles in the present invention are encapsulated particles obtained by coating the surface of a core material with a hydrophilic outer shell material.

The hydrophilic outer shell material is a property capable of forming an outer shell by being unevenly distributed on the surface of a droplet when an in situ polymerization is carried out by dispersing a mixed liquid of a core material constituting material in an aqueous dispersion medium. Refers to a material having. Such a hydrophilic shell material is not particularly limited as long as it has the property, and for example, a hydrophilic functional group such as a carboxyl group, an acid anhydride group, a hydroxyl group, an amino group, or an ammonium ion. Examples thereof include vinyl resins, amorphous polyesters, amorphous polyesteramides, amorphous polyamides, and epoxy resins. Among them, vinyl resin having an acid anhydride group, amorphous polyester and the like are particularly preferable.

In the present specification, the case where a vinyl resin having an acid anhydride group or an amorphous polyester as a main component is used as the hydrophilic outer shell material will be described below as an example, but the present invention is not limited to these. It is not limited to.

Examples of the above vinyl resin having an acid anhydride group include copolymers having one or more acid anhydride groups, and for example, α, β-ethylenic copolymerizable monomer containing an acid anhydride group. Examples thereof include copolymers of monomers and other α, β-ethylenic copolymerizable monomers. Here, as the α, β-ethylenic copolymerizable monomer containing an acid anhydride group,
Itaconic anhydride, crotonic anhydride and the like, compounds represented by the following general formula,

[0017]

[Chemical 1]

(In the formula, Q ₁ and Q ₂ independently represent H, an alkyl group having 1 to 3 carbon atoms, or a halogen atom.)
For example, maleic anhydride, citraconic anhydride, a few anhydrous
-Dimethylmaleic acid, chloromaleic anhydride, dichloromaleic anhydride, bromomaleic anhydride, dibromomaleic anhydride and the like can be mentioned, and maleic anhydride and citraconic anhydride are preferable. Also,
Other α, β-ethylenic copolymerizable monomers include
The same polymerizable monomer as the vinyl resin for core material described later is used.

The amorphous polyester in the present invention is usually one or more divalent alcohol monomers and / or trivalent or higher polyhydric alcohol monomers, and divalent carboxylic acid monomers and / or Those obtained by polycondensation of one or more trivalent or higher polycarboxylic acid monomers are used. In the present invention, in particular, as a constituent monomer, one or more divalent alcohol monomers and one or more divalent carboxylic acid monomers, and further, at least trivalent or more polyhydric alcohol monomers and / or 3 Those obtained by polycondensation using a polycarboxylic acid monomer having a valence of 3 or more are preferred. Such an amorphous polyester is usually contained in an amount of 50 to 100% by weight based on the total weight of the outer shell, and as other components contained in the outer shell, the above-mentioned hydrophilic vinyl resin and amorphous polyamide are used. , Amorphous polyesteramide, epoxy resin and the like can be used in an amount of 0 to 50% by weight.

Examples of the dihydric alcohol component include polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (3.3) -2,
2-bis (4-hydroxyphenyl) propane, polyoxypropylene (2.0) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (2.0) -polyoxyethylene (2.0) -2,2-bis (4-Hydroxyphenyl) propane, polyoxypropylene (6) -2,2-
Alkylene oxide adducts of bisphenol A such as bis (4-hydroxyphenyl) propane, ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl Glycol, 1,4-butenediol, 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, bisphenol A, bisphenol A
Propylene adduct, bisphenol A ethylene adduct, hydrogenated bisphenol A and the like.

Examples of trihydric or higher alcohol components include sorbitol, 1,2,3,6-hexanetetrol, and 1,4.
-Sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,
4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxymethylbenzene and the like can be mentioned. Trivalent alcohol is preferably used. In the present invention, these dihydric alcohol monomers and trihydric or higher polyhydric alcohol monomers can be used alone or in combination.

The acid component is a carboxylic acid component and is a divalent monomer such as maleic acid or fumaric acid.
Citraconic acid, itaconic acid, glutaconic acid, phthalic acid,
Isophthalic acid, terephthalic acid, succinic acid, adipic acid,
Sebacic acid, azelaic acid, malonic acid, n-dodecenylsuccinic acid, n-dodecylsuccinic acid, n-octylsuccinic acid, isooctenylsuccinic acid, isooctylsuccinic acid,
And anhydrides of these acids, or lower alkyl esters.

Examples of the trivalent or higher carboxylic acid component include 1,2,4-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid and 1,2,4- Butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-
2-methylenecarboxypropane, 1,2,4-cyclohexanetricarboxylic acid, tetra (methylenecarboxyl)
Methane, 1,2,7,8-octanetetracarboxylic acid, pyromellitic acid, empol trimer acid and their acid anhydrides,
Lower alkyl ester and the like can be mentioned. Preferably 3
A valent carboxylic acid or its derivative is used. In the present invention, these divalent carboxylic acid monomers and 3
A carboxylic acid monomer having a valence of 3 or more can be used alone or in combination of two or more.

The method for producing the amorphous polyester in the present invention is not particularly limited, and it can be produced by esterification or transesterification reaction using the above monomer. Here, amorphous is one that does not have a definite melting point, and when crystalline polyester is used in the present invention, the amount of energy required for melting is large and the fixability of the resulting toner cannot be improved, which is not preferable.

The amorphous polyester thus obtained has a glass transition point of preferably 50 to 80 ° C, more preferably 55 to 70 ° C.
If it is lower than 50 ° C, the storage stability of the obtained toner will be poor, and if it is higher than 80 ° C, the fixing property of the toner will be poor. In the present invention, the glass transition point is a differential scanning calorimeter (manufactured by Seiko Denshi Kogyo Co., Ltd.) and the temperature rising rate is 10 ° C./min.
The temperature at the intersection of the extension line of the base line below the glass transition point and the tangent line showing the maximum slope from the rising portion of the peak to the apex of the peak, when measured by.

The acid value of the amorphous polyester is an important factor in adjusting the hydrophilic / lipophilic balance. In the present invention, the acid value is 3 to 50 (KOHmg /
g), more preferably 10 to 30
(KOHmg / g). When it is less than 3 (KOHmg / g), the amorphous polyester as the shell material is in si
During the tu polymerization, the toner is less likely to come out at the interface, and the storage stability of the obtained toner is poor, and when it exceeds 50 (KOHmg / g), the polyester is easily transferred to the aqueous phase and the production stability is deteriorated. Here, the method for measuring the acid value is according to JIS K0070.

On the other hand, since the core material of the precursor particles used in the present invention becomes the core material of the capsule toner of the present invention as described above, it is preferable to use a heat-meltable core material containing at least a thermoplastic resin and a colorant. In addition, various components contained in a normal toner may be contained. Examples of the thermoplastic resin include thermoplastic resins such as polyester resin, polyester / polyamide resin, polyamide resin, and vinyl resin,
Preferably, a vinyl resin is used. The glass transition point derived from the thermoplastic resin which is the main component of the heat-fusible core material is preferably 10 to 50 ° C., more preferably 20 to 40 ° C., and the glass transition point is 10.
If it is less than 50 ° C, the storage stability of the obtained capsule toner is deteriorated, and if it exceeds 50 ° C, the fixing strength of the capsule toner is deteriorated, which is not preferable. Such a glass transition point can be adjusted by the resin monomer of the precursor particles, polymerization conditions, etc., but can also be adjusted by the kind of vinyl polymerizable monomer to be absorbed in the precursor particles, the conditions of the second stage reaction, etc. It is possible.

Among the above-mentioned thermoplastic resins, examples of the monomer constituting the vinyl resin (also used as a vinyl polymerizable monomer to be absorbed in the precursor particles described later) include, for example, styrene and o-methyl. Styrene or styrene derivatives such as styrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, p-chlorostyrene, vinylnaphthalene, etc., such as ethylene, propylene, butylene, Ethylenically unsaturated monoolefins such as isobutylene and the like, vinyl esters such as vinyl chloride, vinyl bromide, vinyl fluoride, vinyl acetate, vinyl propionate, vinyl formate and vinyl caproate, for example acrylic acid,
Methyl acrylate, ethyl acrylate, acrylic acid n-
Propyl, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, t-butyl acrylate,
Amyl acrylate, cyclohexyl acrylate, n-octyl acrylate, isooctyl acrylate, decyl acrylate, lauryl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, methoxyethyl acrylate, 2-hydroxyethyl acrylate, acrylic acid Glycidyl, 2-chloroethyl acrylate, phenyl acrylate, α-chloromethyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, T-Butyl methacrylate, amyl methacrylate, cyclohexyl methacrylate, n-octyl methacrylate, isooctyl methacrylate, decyl methacrylate, lauryl methacrylate, methacrylic acid Ethylenic monocarboxylic acids such as 2-ethylhexyl acid, stearyl methacrylate, methoxyethyl methacrylate, 2-hydroxyethyl methacrylate, glycidyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate and their esters. , Ethylenic monocarboxylic acid substitution products such as acrylonitrile, methacrylonitrile, acrylamide, etc., ethylenic dicarboxylic acids such as dimethyl maleate and substitution products thereof, vinyl ketones such as vinyl methyl ketone, for example vinyl methyl ether Vinyl ethers such as vinylidene chloride, vinylidene halides such as vinylidene chloride, N-vinyl compounds such as N-vinylpyrrole, N-vinylpyrrolidone, etc. Is mentioned.

Of the components constituting the resin for the core material according to the present invention, 50 to 90% by weight of styrene or a styrene derivative is used to form the main skeleton of the resin, and ethylenic is used to adjust the thermal characteristics such as the softening temperature of the resin. It is preferable to use 10 to 50% by weight of monocarboxylic acid or its ester because the glass transition point of the resin for core material can be easily controlled.

A crosslinking agent is preferably used in the monomer composition constituting the resin for the core material according to the present invention. In this case, the method of using the cross-linking agent is not particularly limited, but, for example, when preparing the precursor particles (first step reaction)
A mode in which a cross-linking agent is used for polymerization by the second-step reaction, or a cross-linking agent is added for reaction in the case of further absorbing the polymerizable monomer in the precursor particles, or crosslinking is performed in the first-step reaction Examples include a mode in which the agent is not used and only the second step reaction is used.

By thus adding the crosslinking agent and reacting, the molecular weight distribution of the resin component constituting the core material can be adjusted, and it is effective to widen the offset range. In particular, in the embodiment in which the cross-linking agent is added in both the first-step reaction and the second-step reaction, a cross-linking structure is formed in the resin component of the core material in the precursor particles, and a cross-linking structure is further formed in the second-step reaction. Therefore, the offset resistance can be improved not only in high-speed fixing but also in low-speed fixing method.

Examples of the crosslinking agent to be added include divinylbenzene, divinylnaphthalene, polyethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, 1,3
-Butylene glycol dimethacrylate, 1,6-hexylene glycol dimethacrylate, neopentyl glycol dimethacrylate, dipropylene glycol dimethacrylate, polypropylene glycol dimethacrylate, 2,2'-bis (4-methacryloxydiethoxyphenyl) propane, 2,2'-bis (4-acryloxydiethoxyphenyl) propane, trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, dibromoneopentyl glycol dimethacrylate, diallyl phthalate, etc. Appropriate cross-linking agent (2 if necessary)
A combination of two or more species can be used. Divinylbenzene and polyethylene glycol dimethacrylate are preferably used.

The amount of these cross-linking agents used is the total amount used in both the first-step reaction and the second-step reaction, or for the second-step reaction when used only in the second-step reaction. It is recommended to use 0.001 to 15% by weight, preferably 0.1 to 10% by weight, based on the vinyl polymerizable monomer.
When the amount of these cross-linking agents used is more than 15% by weight, the toner obtained is less likely to be melted by heat, resulting in poor heat fixing property or heat pressure fixing property. When the amount used is less than 0.001% by weight, it is difficult to prevent the offset phenomenon in which a part of the toner adheres to the roller surface without being completely fixed to the paper and is transferred to the next paper during thermal pressure fixing. When used in both the first-step reaction and the second-step reaction, the amount of the first-step reaction is 0.1 to 5.0% by weight, preferably 0.5.
~ 3.0% by weight 0.1-5.0 for second stage reaction
%, Preferably 1.0 to 3.0% by weight.
Further, the above monomer may be polymerized in the presence of unsaturated polyester to give a graft or crosslinked polymer, which may be used as a resin for the core material.

Further, as the polymerization initiator used when producing the thermoplastic resin for the core material (also used as a vinyl polymerization initiator to be absorbed in the precursor particles described later), 2,
2'-azobis (2,4-dimethylvaleronitrile), 2,2 '
-Azobisisobutyronitrile, 1,1'-azobis (cyclohexane-1-carbonitrile), 2,2'-azobis-
4-Methoxy-2,4-dimethylvaleronitrile, other azo or diazo polymerization initiators: benzoyl peroxide, methyl ethyl ketone peroxide, isopropyl peroxy carbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide,
Examples thereof include peroxide type polymerization initiators such as lauroyl peroxide and dicumyl peroxide.

Two or more kinds of polymerization initiators may be mixed and used for the purpose of controlling the molecular weight and the molecular weight distribution of the polymer, the reaction time or the like. The amount of the polymerization initiator used is 0.1 to 20 parts by weight, preferably 1 to 10 parts by weight, based on 100 parts by weight of the polymerized monomer.

In the present invention, if the outer shell is an amorphous polyester, it has a negative charge property, but a charge control agent may be added to the core material for adjusting the charge amount, and the negative charge property added. The charge control agent is not particularly limited and may be, for example, a metal-containing azo dye “Varifast Black 3”.
804 "," Bontron S-31 "(above, manufactured by Orient Chemical Co., Ltd.)," T-77 "(manufactured by Hodogaya Chemical Co., Ltd.)," Bontron S-32 "," Bontron S-34 "(above,
Orient Chemical Co., Ltd.), "Aizen Spyron Black T
RH "(manufactured by Hodogaya Chemical Co., Ltd.) and the like, a metal complex of a copper phthalocyanine dye, an alkyl derivative of salicylic acid, for example," Bontron E-81 "," Bontron E-82 ",
"Bontron E-85" (above, manufactured by Orient Chemical Company), quaternary ammonium salt, for example, "COPY CHARGE NX V
P434 "(manufactured by Hoechst), nitroimidazole derivatives and the like. Preferably, T-77 can be used.

The positively chargeable charge control agent is not particularly limited, and examples thereof include nigrosine dyes such as "Nigrosine Base EX", "Oil Black BS", "Oil Black SO", "Bontron N-01", and "Bontron". N-07 "," Bontron N-11 "(above, manufactured by Orient Chemical Co., Ltd.), triphenylmethane dye containing a tertiary amine as a side chain, quaternary ammonium salt compound, for example," Bontron P-51 "( Orient Chemical Co., Ltd.),
Cetyl trimethyl ammonium bromide, "COPY CHARG
Examples thereof include EPX VP435 "(manufactured by Hoechst) and the like, and polyamine resins such as" AFP-B "(manufactured by Orient Chemical Co.) and imidazole derivatives. Preferably, Bontron N-01 can be used.

The above charge control agent is contained in the core material in an amount of 0.1 to 8.0% by weight, preferably 0.2 to 5.0% by weight. In the core material, if necessary, for the purpose of improving offset resistance in heat and pressure fixing, for example, polyolefin, fatty acid metal salt, fatty acid ester, partially saponified fatty acid ester, higher fatty acid, higher alcohol, paraffin wax, amide series Any one or more kinds of offset preventing agents such as wax, polyhydric alcohol ester, silicon varnish, aliphatic fluorocarbon, and silicone oil may be contained.

The above-mentioned polyolefin is, for example, a resin such as polypropylene, polyethylene or polybutene, and has a softening point of 80 to 160 ° C. Examples of the fatty acid metal salt include maleic acid and zinc, magnesium,
Metal salts with calcium, etc .; Metal salts with stearic acid and zinc, cadmium, barium, lead, iron, nickel, cobalt, copper, aluminum, magnesium, etc .; Dibasic lead stearate; Oleic acid and zinc, magnesium, iron , Metal salts with cobalt, copper, lead, calcium, etc .; metal salts with palmitic acid, aluminum, calcium, etc .; caprylate; lead caproate; metal salts with linoleic acid, zinc, cobalt, etc .; calcium ricinoleate; Examples thereof include metal salts of ricinoleic acid and zinc, cadmium, and the like, and mixtures thereof. Examples of the fatty acid ester include maleic acid ethyl ester, maleic acid butyl ester, stearic acid methyl ester, stearic acid butyl ester, palmitic acid cetyl ester, montanic acid ethylene glycol ester and the like. Examples of the partially saponified fatty acid ester include partially saponified calcium of montanic acid ester. Examples of the higher fatty acid include dodecanoic acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, ricinoleic acid, arachidic acid, behenic acid, lignoceric acid, ceracoleic acid, and mixtures thereof. You can Examples of the higher alcohols include dodecyl alcohol, lauryl alcohol, myristyl alcohol, palmityl alcohol, stearyl alcohol, aralkyl alcohol, and behenyl alcohol. Examples of the paraffin wax include natural paraffin, microwax, synthetic paraffin, and chlorinated hydrocarbon. Examples of the amide wax include stearic acid amide, oleic acid amide, palmitic acid amide, lauric acid amide, behenic acid amide, methylenebisstearamide, ethylenebisstearamide, N, N'-m-xylylenebis. Examples thereof include stearic acid amide, N, N'-m-xylylenebis-12-hydroxystearic acid amide, N, N'-isophthalic acid bisstearylamide, and N, N'-isophthalic acid bis-12-hydroxystearylamide. Examples of the polyhydric alcohol ester include glycerin stearate,
Glycerin ricinoleate, glycerin monobehenate,
Examples thereof include sorbitan monostearate, propylene glycol monostearate and sorbitan trioleate. Examples of the silicon varnish include methyl silicon varnish and phenyl silicon varnish. Examples of the aliphatic fluorocarbon include low-polymerization compounds of tetrafluoroethylene and propylene hexafluoride, and fluorine-containing surfactants described in JP-A-53-124428. Of the above offset preventing agents, polyolefin is preferably used, and polypropylene is particularly preferably used. The ratio of these offset preventing agents to the resin in the core material is preferably 1 to 20% by weight.

In the present invention, the colorant is contained in the core material of the encapsulated toner, that is, the precursor particles, but any of the dyes and pigments used in the conventional colorant for toner can be used. Examples of the colorant used in the present invention include various carbon blacks produced by a thermal black method, an acetylene black method, a channel black method, a lamp black method, etc., and a grafted carbon black obtained by coating the surface of the carbon black with a resin. , Nigrosine dye, Phthalocyanine blue, Permanent brown FG,
Brilliant First Scarlet, Pigment Green B, Rhodamine-B Base, Solvent Red 49,
Solvent Red 146, Solvent Blue 35, etc. and mixtures thereof can be mentioned. Usually, the resin in the core material 1
About 1 to 15 parts by weight is used with respect to 00 parts by weight.

In order to produce the magnetic capsule toner, magnetic particles may be added to the core material. As magnetic particles,
For example, ferromagnets such as ferrite and magnetite, metals or alloys exhibiting ferromagnetism such as cobalt, nickel, etc., or compounds containing these elements, or ferromagnetism not containing ferromagnetic elements but exhibiting ferromagnetism by appropriate heat treatment. An alloy such as Manganese-Copper-Aluminum, a type of alloy called Heusler alloy containing manganese and copper such as manganese-copper-tin, or chromium dioxide.
Others can be mentioned. A compound containing a ferromagnetic element is preferably used, and magnetite is particularly preferably used. These magnetic materials have an average particle size of 0.1-1 μm.
It is evenly dispersed in the core material in the form of fine powder. The content is 20 to 70 parts by weight, preferably 30 to 70 parts by weight, per 100 parts by weight of the encapsulated toner. When the fine magnetic powder is added to the toner to make it a magnetic toner, it may be treated in the same manner as in the case of the colorant, but as it is, it has a low affinity for organic materials such as core materials and monomers. Therefore, when the magnetic fine powder is used together with a titanium coupling agent, a silane coupling agent, a so-called coupling agent such as lecithin, preferably a titanium coupling agent or after being treated with the coupling agent, the magnetic fine powder is obtained. It can be dispersed evenly.

The method for producing the precursor particles (first stage reaction) in the present invention using the above raw materials uses the in situ polymerization method from the viewpoint of simplifying the production equipment and the production process.

The method for producing the precursor particles (encapsulated particles) by the in situ polymerization method will be described below. In this production method, the outer shell is formed by dispersing a mixed liquid of a core material constituent material and a hydrophilic outer shell material (for example, amorphous polyester) in an aqueous dispersion medium, and the hydrophilic outer shell material is the surface of the droplet. It can be performed by utilizing the property of being unevenly distributed. That is,
Due to the difference in the solubility index, the core material-constituting material and the hydrophilic outer shell material are separated from each other in the droplets of the mixed solution, and in that state, the polymerization proceeds to form a capsule structure. As a result, an aqueous suspension of precursor particles in which the surface of the core material is coated with the hydrophilic outer shell material is obtained. According to this method, the outer shell is formed as a layer made of a hydrophilic outer shell material having a substantially uniform thickness, so that the toner obtained has the characteristic that the charging characteristics are uniform. It is particularly effective when a material having chargeability such as amorphous polyester is used as the shell material. Specifically, the precursor particles in the present invention can be manufactured by the following steps (a) to (c). (A) a step of dissolving a hydrophilic outer shell material in a mixture composed of a core material constituent material and a coloring agent; and (b) a mixture obtained in step (a) dispersed in an aqueous dispersion medium to obtain a polymerizable composition. And a step (c) of polymerizing the polymerizable composition obtained in the step (b) by an in situ polymerization method.

In the case of this method, it is necessary to contain a dispersion stabilizer in the dispersion medium in order to prevent aggregation and coalescence of dispersoids. Examples of the dispersion stabilizer include gelatin, gelatin derivatives, polyvinyl alcohol, polystyrene sulfonic acid, hydroxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, sodium carboxymethyl cellulose, sodium polyacrylate, sodium dodecylbenzene sulfonate, sodium tetradecyl sulfate, and pentadecyl sulfate. Sodium, sodium octyl sulfate, sodium allyl-alkyl-polyethersulfonate, sodium oleate, sodium laurate, sodium caprate, sodium caprylate, sodium caproate, potassium stearate, calcium oleate, 3,3-disulfonediphenyl Urea-4,4-diazo-bis-amino-β-
Naphthol-6-sulfonate, ortho-carboxybenzene-azo-dimethylaniline, 2,2,5,5-
Tetramethyl-triphenylmethane-4,4-diazo-bis-β-naphthol-sodium disulfonate, colloidal silica, alumina, tricalcium phosphate, ferric hydroxide, titanium hydroxide, aluminum hydroxide and others are used. can do. Preferably, tricalcium phosphate and sodium dodecylbenzene sulfonate can be used. Two or more kinds of these dispersion stabilizers may be used in combination.

Examples of the dispersion medium of the dispersion stabilizer include water, methanol, ethanol, propanol, butanol, ethylene glycol, glycerin, acetonitrile, acetone, isopropyl ether, tetrahydrofuran and dioxane. These can be used alone or as a mixture, but it is preferable to use water as an essential component. Two or more kinds of these dispersion media may be used in combination.

In the production of the precursor particles (the first stage reaction by the in situ polymerization method), the addition amount of the hydrophilic outer shell material such as the amorphous polyester is usually 3 to 100 parts by weight of the core material. 50 parts by weight, preferably 5 to 40 parts by weight,
It is more preferably 5 to 30 parts by weight. If it is less than 3 parts by weight, the outer shell film becomes too thin, resulting in poor storage stability of the toner, and if it exceeds 50 parts by weight, the dispersoid becomes highly viscous, and atomization becomes difficult. Stability deteriorates.

For the purpose of charge control, an appropriate amount of the charge control agent as exemplified above may be added to the outer shell material of the precursor particles of the present invention (that is, the outer shell material of the capsule toner). The charge control agent may be mixed with a toner capable of being used, but the chargeability is controlled by the outer shell itself, so that the addition amount thereof may be small even when they are added.

Next, a method for producing the heat and pressure fixing capsule toner of the present invention in which the seed polymerization method (second step reaction) is carried out using the precursor particles obtained as described above will be described. The production method of the present invention, after adding at least a vinyl polymerizable monomer and a vinyl polymerization initiator to the aqueous suspension of the precursor particles and absorbing them in the precursor particles, It is for polymerizing a monomer component. In the production method of the present invention, immediately after the production of the precursor particles by the in situ polymerization method, at least the vinyl polymerizable monomer and the vinyl polymerization initiator are added to the precursor particles in a suspended state. You may make it absorb and carry out seed polymerization of the monomer component in this precursor particle. By doing so, the manufacturing process can be further simplified. The vinyl polymerizable monomer or the like to be absorbed in the precursor particles may be added in advance as a water emulsion.

The water emulsion to be added is obtained by emulsifying and dispersing a vinyl polymerizable monomer and a vinyl polymerization initiator in water together with a dispersion stabilizer. In addition, a crosslinking agent, an offset preventing agent, a charge control agent, etc. Can also be included. The vinyl polymerizable monomer used in the second step reaction may be the same as that used in the production of the precursor particles by the first step reaction. Also, vinyl polymerization initiator, crosslinking agent, dispersion stabilizer,
The same precursor particles as described above can be used.
The amount of the crosslinking agent used in the second reaction is also as described above.

Further, in order to further improve the storage stability of the toner, the hydrophilic shell material such as the above-mentioned amorphous polyester may be added to the water emulsion. The amount added at that time is usually 1 to 20 parts by weight, preferably 3 to 15 parts by weight, based on 100 parts by weight of the core material. Therefore, for example, in the first step reaction, amorphous polyester is used as the hydrophilic shell material,
Amorphous polyester is added also in the stage reaction, or a vinyl resin having an acid anhydride group is used in the first stage,
There are various modes such as addition of amorphous polyester in the second stage reaction. Such a water emulsion can be prepared by uniformly dispersing it with an ultrasonic oscillator or the like.

The acid value of the amorphous polyester used in the second step reaction is 3 to 50 (K) as in the case of the first step reaction.
OHmg / g), and more preferably 10 to 30 (KOHmg / g). 3 (KOHmg
If less than 50 g / g), the amorphous polyester as the shell material is less likely to come out at the interface during seed polymerization, and the storage stability of the obtained toner is poor. If it exceeds 50 (KOHmg / g), the polyester is in the aqueous phase. It is easy to shift to, and manufacturing stability deteriorates. Here, the method for measuring the acid value is according to JIS K0070.

The water emulsion is added in such an amount that the vinyl polymerizable monomer is used in an amount of 10 to 20 relative to 100 parts by weight of the precursor particles.
Adjust so that it is 0 parts by weight. If it is less than 10 parts by weight, the fixing property is not improved, and if it exceeds 200 parts by weight, it becomes difficult to uniformly absorb the monomer in the precursor particles.

By the addition of the water emulsion, the vinyl polymerizable monomer is absorbed in the precursor particles and the precursor particles swell. The present invention polymerizes the monomer component in the precursor particles in this state (second stage reaction), and can be said to be a seed polymerization method using the precursor particles as seed particles.

According to the manufacturing method of the present invention as described above,
The following points are further improved as compared with the case where the capsule toner is manufactured by the in situ polymerization method alone. That is, the capsule toner produced by the in situ polymerization method is superior to the conventional one in terms of low-temperature fixability and storage stability, but by further performing the seed polymerization method, a more uniform outer shell is formed in terms of interface science. Further, the storage stability is further improved. In addition, since the polymerizable monomer of the core material can be polymerized in two stages (first stage reaction and second stage reaction), the heat in the core substance can be further improved by appropriately using a crosslinking agent. The molecular weight of the plastic resin can be easily controlled, and the low temperature fixing property and the offset resistance can be improved. In particular, it is possible to provide a toner suitable not only for high-speed fixing but also for low-speed fixing.

The particle diameter of the capsule toner of the present invention produced by the above method is not particularly limited, but the average particle diameter is usually 3 to 30 μm. The thickness of the outer shell of the capsule toner is preferably 0.01 to 1 .mu.m. If it is less than 0.01 .mu.m, the blocking resistance deteriorates, and if it exceeds 1 .mu.m, the heat melting property deteriorates, which is not preferable.

If necessary, a fluidity improver, a cleaning property improver and the like can be used in the encapsulated toner of the present invention. As the fluidity improver, for example, silica,
Alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, silica sand, clay, mica, wollastonite, diatomaceous earth, chromium oxide, cerium oxide, red iron oxide, antimony trioxide, Magnesium oxide, zirconium oxide,
Examples thereof include barium sulfate, barium carbonate, calcium carbonate, silicon carbide and silicon nitride. Fine silica powder is particularly preferable. The fine silica powder is Si
It is a fine powder having a —O—Si bond and may be produced by a dry method or a wet method. In addition to anhydrous silicon dioxide, it may be any of aluminum silicate, sodium silicate, potassium silicate, magnesium silicate, zinc silicate, etc., but 85% by weight of SiO ₂
Those including the above are preferable. Further, a fine powder of silica surface-treated with a silane coupling agent, a titanium coupling agent, a silicone oil, a silicone oil having an amine in a side chain, or the like can be used.

Examples of the cleaning property improver include metal salts of higher fatty acids typified by zinc stearate and fine particles of fluorine-based high molecular weight particles. Further additives for adjusting the developability, for example, methacrylic acid methyl ester,
Fine particles of a polymer such as methacrylic acid butyl ester may be used. Further, a small amount of carbon black may be used to reduce the electric resistance on the toner surface.
As the carbon black, conventionally known ones, for example, various ones such as furnace black, channel black and acetylene black can be used.

The capsule toner of the present invention is used alone as a developer when it contains magnetic fine powder, and it is a non-magnetic one-component developer when it does not contain magnetic fine powder. Alternatively, a two-component developer can be prepared and used by mixing with a carrier. The carrier is not particularly limited, but iron powder, ferrite, glass beads or the like, or those coated with a resin thereof, further magnetite fine powder, a resin carrier obtained by kneading ferrite fine powder into a resin is used, and is mixed with a toner carrier. The ratio is 0.5 to 20% by weight. The carrier has a particle size of 15 to 500 μm.

The capsule toner of the present invention gives good fixing strength by fixing to a recording material such as paper by using heat and pressure together. As a heat and pressure fixing method, if heat and pressure are used together. , A known heat roller fixing method, or, for example, as described in JP-A-2-190870, an unfixed toner image on a recording material is passed through the heat-resistant sheet by a heating means composed of a heating section and a heat-resistant sheet. To heat and melt,
A fixing method of fixing, or a heating body fixedly supported as described in, for example, Japanese Patent Laid-Open No. 162356/1990, and a pressurizing member that is in pressure contact with the heating body and is in close contact with the heating body through a film. A method such as a method of heating and fixing the visible image of the toner on the recording material depending on the member is suitable for fixing the capsule toner of the present invention.

[0060]

EXAMPLES The present invention will be described in more detail with reference to Examples, Comparative Examples and Test Examples, but the present invention is not limited to these Examples.

Resin Production Example Propylene oxide adduct of bisphenol A 36
7.5 g (hereinafter abbreviated as BPA / PO), 146.4 g of ethylene oxide adduct of bisphenol A (hereinafter BP
A. EO), 126.0 g of terephthalic acid (hereinafter T
PA), 40.2 g of dodecenyl succinic anhydride (abbreviated as DSA below) and 77.7 g of trimellitic anhydride (abbreviated as TMA hereinafter) were placed in a glass 2-liter four-necked flask, a thermometer, and a stainless steel stirring rod. , A down-flow type condenser, and a nitrogen introduction tube were attached, and the reaction was carried out at 220 ° C. under a nitrogen stream in a mantle heater. The degree of polymerization was traced from the softening point according to ASTM E28-67, and the reaction was terminated when the softening point reached 110 ° C. This resin is called resin A. The composition of this resin A is shown in Table 1.
Shown in. The glass transition point of the obtained resin was measured by a differential scanning calorimeter (manufactured by Seiko Denshi Kogyo Co., Ltd.), and the value, softening point, and acid value are shown in Table 2 together. The acid value is JI
It was measured by a method according to S K0070. In the present invention, the softening point is a Koka type flow tester (manufactured by Shimadzu Corporation), and a load of 20 Kg / cm ² is applied by a plunger while heating a 1 cm ³ sample at a heating rate of 6 ° C./min. A nozzle with a diameter of 1 mm and a length of 1 mm is pushed out, whereby the plunger drop amount (flow value) of the flow tester-temperature curve is drawn and the temperature corresponding to h / 2 when the height of the S curve is h Say.

[0062]

[Table 1]

[0063]

[Table 2]

Example 1 69.0 parts by weight of styrene, 31.0 parts by weight of 2-ethylhexyl acrylate, 6.0 parts by weight of 2,2'-azobisisobutyronitrile, 15.0 parts by weight of resin A, and carbon. 7.0 parts by weight of black "# 44" (manufactured by Mitsubishi Kasei Co., Ltd.) was added and charged into an attritor (manufactured by Mitsui Miike Kakoki Co., Ltd.) and dispersed at 10 ° C for 5 hours to obtain a polymerizable composition. . Then, 240 g of the above polymerizable composition was added to 560 g of an aqueous colloidal solution containing 4% by weight of tricalcium phosphate, which had been prepared in advance in a 2 liter glass separable flask, and a TK homomixer (made by Tokushu Kika Kogyo Co., Ltd.). Was emulsified and dispersed at room temperature for 2 minutes at 10,000 rpm. Then, a 4-port glass lid was attached, a reflux cooling tube, a thermometer, a nitrogen introduction tube, and a stainless steel stirring rod were attached, and the glass was installed in an electric heating mantle heater. While continuing stirring under nitrogen, the temperature was raised to 85 ° C. as the first stage polymerization, and the reaction was performed for 10 hours to obtain seed particles. This was cooled to room temperature to obtain precursor particles. Next, 13.0 parts by weight of styrene prepared by an ultrasonic oscillator (US-150, manufactured by Nippon Seiki Seisakusho Ltd.) in an aqueous suspension of the precursor particles, 2
-Ethylhexyl acrylate 7.0 parts by weight, 2,2 '
-Azobisisobutyronitrile 0.4 part by weight, divinylbenzene 0.22 part by weight, sodium lauryl sulphate 0.
40.7 parts by weight of a water emulsion comprising 1 part by weight and 20 parts by weight of water was added dropwise to swell the precursor particles. Immediately after dropping, observation with an optical microscope revealed that no emulsion droplets were observed and that swelling was completed within an extremely short time. Therefore, the temperature was raised to 85 ° C. and reacted for 10 hours as the second stage polymerization while continuing stirring under nitrogen. After cooling, the dispersion medium is dissolved with a 10% hydrochloric acid aqueous solution, filtered, washed with water, air-dried, and then at 45 ° C. for 12 hours, 2
It was dried under reduced pressure at 0 mmHg and classified by an air classifier to obtain a capsule toner having an outer shell of amorphous polyester with an average particle diameter of 8 μm. To 100 parts by weight of this capsule toner, 0.4 parts by weight of hydrophobic silica fine powder "Aerosil R-972" (manufactured by Nippon Aerosil Co., Ltd.) was added and mixed to obtain a capsule toner of the present invention. This is designated as Toner 1. The glass transition point derived from the resin in the core material was 27.4 ° C., and the softening point of Toner 1 was 108.2 ° C.

Example 2 65.0 parts by weight of styrene, 31.0 parts by weight of 2-ethylhexyl acrylate, and 6.0 parts by weight of 2,2'-azobisisobutyronitrile were added with 15.0 parts by weight of Resin A. ,
Resin A was dissolved. Carbon black "GPE-3" grafted with styrene after the resin A was dissolved
20 parts by weight (manufactured by Ryoyu Kogyo Co., Ltd.) was added and dispersed for 1 hour with a magnetic stirrer to obtain a polymerizable composition. Next, in a 2 liter glass separable flask, an aqueous colloidal solution 5 containing 4% by weight of tricalcium phosphate was prepared in advance.
240 g of the above polymerizable composition was added to 60 g,
It was emulsified and dispersed using a TK homomixer. Then, a 4-port glass lid was attached, a reflux cooling tube, a thermometer, a nitrogen introduction tube, and a stainless steel stirring rod were attached, and the glass was installed in an electric heating mantle heater. While continuing stirring under nitrogen, the temperature of the first stage polymerization was raised to 85 ° C., a polymerization reaction was carried out for 10 hours to obtain seed particles, and the particles were cooled to room temperature to obtain precursor particles. Then, 26.0 parts by weight of styrene and 1 part of 2-ethylhexyl acrylate were added to the aqueous suspension of the precursor particles.
A mixture of 4.0 parts by weight, 0.8 parts by weight of 2,2′-azobisisobutyronitrile, and 0.40 parts by weight of divinylbenzene was added dropwise, and the mixture was stirred at room temperature for 3 hours under nitrogen with stirring. As the second stage polymerization, the temperature was raised to 85 ° C. and the reaction was carried out for 10 hours. After cooling, dissolve the dispersion medium with 10% aqueous hydrochloric acid, filter, wash with water, air-dry, and then at 45 ° C. for 12 hours, 2
It was dried under reduced pressure at 0 mmHg and classified by an air classifier to obtain a capsule toner having an outer shell of amorphous polyester with an average particle diameter of 8 μm. To 100 parts by weight of this capsule toner, 0.4 parts by weight of hydrophobic silica fine powder "Aerosil R-972" was added and mixed to obtain an encapsulated toner of the present invention. This is designated as toner 2. The glass transition point derived from the resin in the core material is 28.5 ° C, and the softening point of Toner 2 is 115.0 ° C.
Met.

Example 3 65.0 parts by weight of styrene, 31.0 parts by weight of 2-ethylhexyl acrylate and 6.0 parts by weight of 2,2'-azobisisobutyronitrile were added with 15.0 parts by weight of Resin A. ,
Resin A was dissolved. Carbon black "GPE-3" grafted with styrene after the resin A was dissolved
20 parts by weight (manufactured by Ryoyu Kogyo Co., Ltd.) was added and dispersed for 1 hour with a magnetic stirrer to obtain a polymerizable composition. Next, in a 2 liter glass separable flask, an aqueous colloidal solution 5 containing 4% by weight of tricalcium phosphate was prepared in advance.
240 g of the above polymerizable composition was added to 60 g,
It was emulsified and dispersed using a TK homomixer. Then, a 4-port glass lid was attached, a reflux cooling tube, a thermometer, a nitrogen introduction tube, and a stainless steel stirring rod were attached, and the glass was installed in an electric heating mantle heater. While continuing stirring under nitrogen, the temperature of the first stage polymerization was raised to 85 ° C., a polymerization reaction was carried out for 10 hours to obtain seed particles, and the particles were cooled to room temperature to obtain precursor particles. Next, 13.0 parts by weight of styrene and 7.0 parts by weight of 2-ethylhexyl acrylate prepared by an ultrasonic oscillator (US-150, manufactured by Nippon Seiki Seisakusho Co., Ltd.) in an aqueous suspension of the precursor particles. Parts, 2,2'-azobisisobutyronitrile 0.4 parts by weight, divinylbenzene 0.22 parts by weight, resin A 2.0 parts by weight, sodium lauryl sulfate 0.1 parts by weight, and water 20 parts by weight. Emulsion 42.7
By weight, a second part of the polymerization was carried out by raising the temperature to 85 ° C. and reacting for 10 hours while continuing stirring under nitrogen.
After cooling, dissolve the dispersion medium with 10% hydrochloric acid aqueous solution, filter, wash with water, air-dry, then dry under reduced pressure at 20 mmHg for 12 hours at 45 ° C., classify with an air classifier, and an outer shell with an average particle size of 8 μm is obtained. An amorphous polyester capsule toner was obtained. To 100 parts by weight of this capsule toner, 0.4 parts by weight of hydrophobic silica fine powder "Aerosil R-972" was added and mixed to obtain an encapsulated toner of the present invention. This is designated as toner 3. The glass transition point derived from the resin in the core material is 2
The softening point of Toner 3 was 8.0 ° C. and 108.5 ° C.

Example 4 In Example 1, instead of 15.0 parts by weight of Resin A, polyester-amide resin (propylene oxide adduct of bisphenol A / terephthalic acid / meta-xylylenediamine = 95/90/5 molar ratio, Using 15.0 parts by weight of a softening point of 105 ° C., a glass transition point of 60 ° C. and an acid value of 15 KOHmg / g), the surface treatment was performed in the same manner as in Example 1 to obtain a capsule toner. This is designated as toner 4. Glass transition point due to resin in core material is 27.5 ° C
And the softening point of Toner 4 was 105.9 ° C.

Example 5 69.0 parts by weight of styrene, 31.0 parts by weight of 2-ethylhexyl acrylate, 6.0 parts by weight of 2,2'-azobisisobutyronitrile, 0.5 part by weight of divinylbenzene and Resin A were added. 15.0 parts by weight of was added to dissolve Resin A.
After the resin A was dissolved, 20 parts by weight of carbon black "GPE-3" (manufactured by Ryoyu Kogyo Co., Ltd.) grafted with styrene was added and dispersed for 1 hour with a magnetic stirrer to obtain a polymerizable composition. Then, 240 g of the above polymerizable composition was added to 560 g of an aqueous colloidal solution containing 4% by weight of tricalcium phosphate prepared in a 2 liter glass separable flask, and TK homomixer (made by Tokushu Kika Kogyo Co., Ltd.) was added. ) Was used for emulsion dispersion. Next, put a 4-port glass lid, attach a reflux condenser, a thermometer, a nitrogen inlet tube, and a stainless steel stirring rod, and install it in an electric heating mantle heater. As eye polymerization, the temperature was raised to 85 ° C., a polymerization reaction was carried out for 10 hours, and seed particles were cooled to room temperature to obtain precursor particles. Then, 26.0 parts by weight of styrene and 14.0 parts by weight of 2-ethylhexyl acrylate prepared by an ultrasonic oscillator (US-150, manufactured by Nippon Seiki Seisakusho Co., Ltd.) in an aqueous suspension of the precursor particles. Parts, 2,2'-azobisisobutyronitrile 1.6 parts by weight, divinylbenzene 0.8 parts by weight, sodium lauryl sulfate 0.2 parts by weight, and water emulsion 802.6 parts by weight 122.6 parts by weight. The mixture was added dropwise, and the temperature was raised to 85 ° C. as a second stage polymerization while reacting for 10 hours while continuing stirring under nitrogen. 10% after cooling
The dispersion medium is dissolved in an aqueous solution of hydrochloric acid, filtered, washed with water, air-dried, and then dried under reduced pressure at 20 mmHg at 45 ° C. for 12 hours.
The particles were classified by an air classifier to obtain a capsule toner having an average particle diameter of 8 μm and an outer shell made of amorphous polyester. To 100 parts by weight of this capsule toner, 0.4 parts by weight of hydrophobic silica fine powder "Aerosil R-972" was added and mixed to obtain an encapsulated toner of the present invention. This is designated as toner 5. The glass transition point derived from the resin in the core material was 33.0 ° C, and the softening point of Toner 5 was 112.5 ° C.

Example 6 69.0 parts by weight of styrene, 31.0 parts by weight of 2-ethylhexyl acrylate, 6.0 parts by weight of 2,2'-azobisisobutyronitrile, 0.8 parts by weight of divinylbenzene and Resin A were added. 15.0 parts by weight of was added to dissolve Resin A.
After the resin A was dissolved, 20 parts by weight of carbon black "GPE-3" (manufactured by Ryoyu Kogyo Co., Ltd.) grafted with styrene was added and dispersed for 1 hour with a magnetic stirrer to obtain a polymerizable composition. Then, 240 g of the above polymerizable composition was added to 560 g of an aqueous colloidal solution containing 4% by weight of tricalcium phosphate prepared in a 2 liter glass separable flask and emulsified and dispersed using a TK homomixer. . Next, put a glass lid with 4 mouths,
A reflux condenser, a thermometer, a nitrogen inlet tube, and a stainless steel stirring rod were attached, and the reactor was placed in an electric heating mantle heater. While continuing stirring under nitrogen, the temperature was raised to 85 ° C for the first stage polymerization for 10 hours. Polymerization reaction was performed to obtain seed particles, and the particles were cooled to room temperature to obtain precursor particles. Then, 26.0 parts by weight of styrene and 14.0 parts by weight of 2-ethylhexyl acrylate prepared by an ultrasonic oscillator (US-150, manufactured by Nippon Seiki Seisakusho Co., Ltd.) in an aqueous suspension of the precursor particles. Department,
1.6 parts by weight of 2,2′-azobisisobutyronitrile,
122.6 parts by weight of an emulsion solution consisting of 0.8 parts by weight of divinylbenzene, 0.2 parts by weight of sodium lauryl sulfate, and 80 parts by weight of water was added dropwise, and stirring was continued under nitrogen to conduct a second-stage polymerization of 85 parts. The temperature was raised to ° C and the reaction was carried out for 10 hours. After cooling, dissolve the dispersion medium with 10% aqueous hydrochloric acid, filter, wash with water, air-dry, and then at 45 ° C. for 12 hours, 2
It was dried under reduced pressure at 0 mmHg and classified by an air classifier to obtain a capsule toner having an outer shell of amorphous polyester with an average particle diameter of 8 μm. To 100 parts by weight of this capsule toner, 0.4 parts by weight of hydrophobic silica fine powder "Aerosil R-972" was added and mixed to obtain an encapsulated toner of the present invention. This is designated as toner 6. The glass transition point derived from the resin in the core material is 35.6 ° C, and the softening point of Toner 6 is 122.0 ° C.
Met.

Example 7 69.0 parts by weight of styrene, 31.0 parts by weight of 2-ethylhexyl acrylate, 6.0 parts by weight of 2,2'-azobisisobutyronitrile, 0.8 parts by weight of divinylbenzene and Resin A were added. 15.0 parts by weight of was added to dissolve Resin A.
After the resin A was dissolved, 20 parts by weight of carbon black "GPE-3" (manufactured by Ryoyu Kogyo Co., Ltd.) grafted with styrene was added and dispersed for 1 hour with a magnetic stirrer to obtain a polymerizable composition. Then, 240 g of the above polymerizable composition was added to 560 g of an aqueous colloidal solution containing 4% by weight of tricalcium phosphate prepared in a 2 liter glass separable flask and emulsified and dispersed using a TK homomixer. It was Next, put a 4-port glass lid, attach a reflux condenser, a thermometer, a nitrogen inlet tube, and a stainless steel stirring rod, and install it in an electric heating mantle heater. 85 ° C for eye polymerization
The temperature was raised to 10 ° C. and the polymerization reaction was carried out for 10 hours to obtain seed particles, which were cooled to room temperature to obtain precursor particles. Then, 26.0 parts by weight of styrene prepared by an ultrasonic oscillator and 2-ethylhexyl acrylate 1 were added to an aqueous suspension of the precursor particles.
An emulsion solution consisting of 4.0 parts by weight, 2,2′-azobisisobutyronitrile 2.4 parts by weight, divinylbenzene 0.8 parts by weight, sodium lauryl sulfate 0.2 parts by weight, and water 80 parts by weight 123. 4 parts by weight was added dropwise, and while continuing stirring under nitrogen, the temperature was raised to 85 ° C. as the second stage polymerization and reacted for 10 hours. After cooling, dissolve the dispersion medium with 10% hydrochloric acid aqueous solution, filter, wash with water, air-dry, then dry under reduced pressure at 20 mmHg for 12 hours at 45 ° C., classify with an air classifier, and an outer shell with an average particle size of 8 μm is obtained. An amorphous polyester capsule toner was obtained. This capsule toner 10
Hydrophobic silica fine powder "Aerosil R-97" in 0 part by weight
2 "0.4 parts by weight was added and mixed to obtain a capsule toner of the present invention. This is designated as toner 7. The glass transition point derived from the resin in the core material was 36.1 ° C, and the softening point of Toner 7 was 118.5 ° C.

Comparative Example 1 70.0 parts by weight of styrene, 30.0 parts by weight of 2-ethylhexyl acrylate, 1.0 part by weight of divinylbenzene,
Carbon black "# 44" (manufactured by Mitsubishi Kasei) 10.0
2,2'-azobisisobutyronitrile 3.
5 parts by weight, 9.5 parts by weight of 4,4′-diphenylmethane diisocyanate “Millionate MT” (manufactured by Nippon Polyurethane Industry Co., Ltd.) were added, and the mixture was put into an attritor (manufactured by Mitsui Miike Kakoki Co., Ltd.) and heated at 10 ° C. for 5 minutes. Time dispersed,
A polymerizable composition was obtained. Then, 240 g of the above polymerizable composition was added to 560 g of an aqueous colloidal solution containing 4% by weight of tricalcium phosphate prepared in advance in a 2 liter glass separable flask, and TK homomixer (made by Tokushu Kika Kogyo Co., Ltd. ), The rotation speed is 120 at 5 ° C.
It was emulsified and dispersed at 00 rpm for 2 minutes. Next, a 4-port glass lid was attached, a reflux cooling tube, a thermometer, a nitrogen introduction tube, and a stainless steel stirring rod were attached, and the lid was placed in an electric heating mantle heater. 7.5 parts by weight of ethylenediamine,
Dibutyltin dilaurate 0.5 part by weight, ion-exchanged water 4
0 g of a mixed solution was prepared and added dropwise over 30 minutes while stirring with a dropping funnel. Then, while continuing stirring under nitrogen, the temperature was raised to 80 ° C. and the reaction was performed for 10 hours.
After cooling, dissolve the dispersion medium with 10% aqueous hydrochloric acid, filter,
After washing with water, it was dried under reduced pressure at 20 mmHg for 12 hours at 45 ° C., and classified by an air classifier to obtain a capsule toner having an average particle diameter of 8 μm and an outer shell made of polyurea resin. To 100 parts by weight of this capsule toner, hydrophobic silica fine powder "Aerosil R-972" (manufactured by Nippon Aerosil Co., Ltd.) was added.
4 parts by weight were added and mixed to obtain a capsule toner. This is designated as comparative toner 1. The glass transition point derived from the resin in the core material is 33.5 ° C, and the softening point of Comparative Toner 1 is 13
It was 7.0 ° C.

Comparative Example 2 69.0 parts by weight of styrene, 31.0 parts by weight of 2-ethylhexyl acrylate, 7.0 parts by weight of carbon black "# 44" (manufactured by Mitsubishi Kasei Co., Ltd.), low molecular weight polyethylene (Mitsui Petrochemical Co., Ltd.) Industry, Mitsui High Wax 210
P) (2.0 parts by weight) and a charge control agent (Hodogaya Chemical Co., Ltd., Aizenspirone Black TRH) (1.5 parts by weight) were mixed for 10 hours with an attritor. To this dispersion was added 2,2'-azobisisobutyronitrile 6.
A polymerizable composition was obtained by dissolving 0 part by weight. Then 2
To a liter glass separable flask, 240 g of the above polymerizable composition was added to 560 g of an aqueous colloidal solution containing 4% by weight of tricalcium phosphate, and a TK homomixer (made by Tokushu Kika Kogyo Co., Ltd.) was used. 1
It was emulsified and dispersed at 0 ° C. for 10 hours. Next, cover the glass with four ports, attach a reflux condenser, a thermometer, a nitrogen inlet tube, and a stainless steel stirring rod, and install the heater in an electric heating mantle heater. While continuing stirring under nitrogen, As the second stage polymerization, the temperature was raised to 85 ° C., a polymerization reaction was carried out for 10 hours to obtain seed particles, and the particles were cooled to room temperature to obtain precursor particles. Then
In the aqueous suspension of the precursor particles, an ultrasonic oscillator (US-
150, manufactured by Nippon Seiki Seisakusho Ltd.), 13.0 parts by weight of styrene, 7.0 parts by weight of 2-ethylhexyl acrylate, 0.4 parts by weight of 2,2′-azobisisobutyronitrile, divinylbenzene. 40.7 parts by weight of a water emulsion consisting of 0.22 parts by weight, sodium lauryl sulfate 0.1 part by weight, and water 20 parts by weight 40.7 parts by weight were added dropwise, and the stirring was continued under nitrogen while the second stage polymerization was carried out at 85 ° C. The temperature was raised to 10 minutes and the reaction was allowed to proceed for 10 hours. After cooling, the dispersion medium is dissolved with a 10% aqueous hydrochloric acid solution, filtered, washed with water, air-dried, dried under reduced pressure at 20 mmHg for 12 hours at 20 ° C., and classified with an air classifier to obtain a seed polymerization toner having an average particle size of 8 μm. Got To 100 parts by weight of this synthetic toner, 0.4 parts by weight of hydrophobic silica fine powder "Aerosil R-972" (manufactured by Nippon Aerosil Co., Ltd.) was added and mixed to obtain a synthetic toner. Compare this with Toner 2
And Comparative Toner 2 had a glass transition point of 30.6 ° C. and a softening point of 109.0 ° C.

Comparative Example 3 69.0 parts by weight of styrene, 31.0 parts by weight of 2-ethylhexyl acrylate, 0.9 parts by weight of divinylbenzene,
To 7.0 parts by weight of carbon black "# 44" (manufactured by Mitsubishi Kasei Co., Ltd.), 20 parts by weight of Resin A and 3.5 parts by weight of 2,2'-azobisisobutyronitrile were added, and an attritor (Mitsui Miike Kakoki Co., Ltd.) and dispersed at 10 ° C. for 5 hours to obtain a polymerizable composition. Then, 240 g of the above polymerizable composition was added to 560 g of an aqueous colloidal solution containing 4% by weight of tricalcium phosphate prepared in advance in a 2 liter glass separable flask, and a TK homomixer (made by Tokushu Kika Kogyo Co., Ltd. ), The rotation speed is 120 at 5 ° C.
It was emulsified and dispersed at 00 rpm for 5 minutes. Then, a 4-port glass lid was attached, a reflux cooling tube, a thermometer, a nitrogen introduction tube, and a stainless steel stirring rod were attached, and the glass was placed in an electric heating mantle heater. While continuing to stir under nitrogen, 85
The temperature was raised to ° C and the reaction was carried out for 10 hours. After cooling, 10%
Dissolve the dispersion medium with aqueous hydrochloric acid, filter, wash with water, and then
It was dried under reduced pressure at 20 mmHg for 12 hours at 5 ° C., and then classified by an air classifier to obtain a capsule toner having an outer shell of amorphous polyester having an average particle diameter of 8 μm. To 100 parts by weight of this capsule toner, hydrophobic silica fine powder "Aerosil"
R-972 "(manufactured by Nippon Aerosil Co., Ltd.) (0.4 parts by weight) was added and mixed to obtain a capsule toner. This is designated as comparative toner 3. The glass transition point derived from the resin in the core material is 3
0.6 ° C., and the softening point of comparative toner 3 is 125.5 ° C.
Met.

Test Example For each of the toners obtained in the above Examples and Comparative Examples,
The storage stability, the charge amount measurement, and the fixability test were evaluated. At this time, the storage stability test evaluated the toner alone. Further, the charge amount measurement and the fixing property test were carried out by placing 6 parts by weight of each toner and 94 parts by weight of spherical ferrite powder coated with styrene / methylmethacrylate resin having a particle size of 250-400 mesh in a poly container and rotating at 150 rpm.
The developer was prepared by rotating and mixing the entire container on a roller for 20 minutes at m. The resulting developer was evaluated for storage stability, charge amount and fixability.

(1) Regarding storage stability, each toner 5
g is weighed in a 90 mmφ aluminum cup and the temperature is 50 ° C.
The degree of agglomeration generated when left for 24 hours under the condition of relative humidity of 40% was evaluated. The results are shown in Table 3. (2) The charge amount was measured by the blow-off type charge amount measuring device described below. That is, using a specific charge measuring device equipped with a Faraday cage, a condenser, and an electrometer, first, prepare a brass-type measuring cell equipped with a 500-mesh (measurable size that does not allow carrier particles to pass) stainless steel mesh. W (g) (0.15 to 0.20 g) was added to the developer. Next, after suctioning for 5 seconds from the suction port, the air pressure regulator is 0.6 kg.
Blow was performed for 5 seconds at a pressure indicating f / cm ² to remove only the toner from the cell. At this time, the voltage of the electrometer 2 seconds after the start of blowing was defined as V (volt). Here, if the electric capacity of the condenser is C (μF), the specific charge Q / m of this toner is obtained by the following equation. Q / m (μC / g) = C × V / m Here, m is the weight of the toner contained in the developer in W (g), and the weight in the developer is T (g), When the weight of the agent is D (g), the toner concentration of the sample is T / D
It is expressed as × 100 (%), and m is calculated by the following formula. m (g) = W x (T / D) Table 3 shows the result of measurement of the charge amount of the developer prepared under the normal environment.
Shown in.

(3) The fixability was evaluated by the method described below. That is, a commercially available electrophotographic copying machine (photoreceptor: toner 1 to 7, comparative toner 2 to
In the case of No. 3, selenium-arsenic was used, in the case of Comparative toner 1, the organic photoconductor was used, and the rotation speed of the fixing roller was 255 mm /
sec (toner 1 to 4, comparative toner 1 to 3) or 80 m
Images were printed using m / sec (toner 5 to 7), the thermal pressure temperature in the fixing device was made variable, and the oil coating device was removed). The fixing temperature was controlled from 70 to 240 ° C., and the fixing property and offset property of the image were evaluated.
The results are shown in Table 3. The minimum fixing temperature here is a reflection densitometer of Macbeth Co. before and after rubbing 5 times on the image fixed through a fixing machine by putting a load of 500 g on a sand eraser with a bottom of 15 mm × 7.5 mm and rubbing. The optical reflection density is measured by means of, and it means the temperature of the fixing roller when the fixing rate exceeds 70% as defined below. Fixing rate = (image density after rubbing / image density before rubbing) ×
100 Offset resistance was evaluated by measuring the low temperature offset disappearance temperature and the high temperature offset generation temperature. That is, the temperature of the surface of the heat roller was raised by 5 ° C. in the range of 70 to 240 ° C. to perform a copy test, and the adhesion of the toner on the surface of the heat roller was visually evaluated at each temperature.

[0077]

[Table 3]

As is clear from Table 3, the toners 1 to 7 of the present invention maintained a good image although their charge amount values were slightly higher. Regarding the storage stability (blocking resistance), the toners 1 to 7 of the present invention and the comparative toners 1 and 3 have good storage stability, whereas the comparative toner 2 does not have a capsule structure. Moreover, since the glass transition point was low, the storage stability was poor. Further, all of the toners 1 to 7 of the present invention had a low minimum fixing temperature and a wide non-offset region, but the comparative toner 1 had a high melting point of polyurea (300 ° C. or higher) and a high minimum fixing temperature (200). ℃ or more). In particular, in toners 5 to 7, the core material in the precursor particles had a crosslinked structure and had a wide non-offset region in the fixing system at a low speed. Comparative toner 2 had a low minimum fixing temperature, but had a slightly narrow non-offset region. Comparative Toner 3 had good fixability, but since it did not undergo seed polymerization, Toners 1 to 7 of the present invention
Showed better fixability.

[0079]

INDUSTRIAL APPLICABILITY In the production method of the present invention, the surface of the core material is coated with a hydrophilic outer shell material such as amorphous polyester to obtain precursor particles, and the vinyl polymerizable monomer is absorbed in the precursor particles. The toner obtained by polymerizing after being allowed to have not only improved storage stability, but also excellent offset resistance in the thermal pressure fixing method, can be fixed at a low temperature, and is clear without fog. An image can be formed. Further, by making the resin component in the core material a crosslinked structure, the offset resistance becomes more excellent not only in the fixing method at a high speed but also at a low speed.

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Claims (17)

[Claims] 1. A process for producing a heat and pressure fixing capsule toner comprising a heat-fusible core material containing at least a thermoplastic resin and a colorant, and an outer shell provided so as to cover the surface of the core material. , Precursor particles by coating the surface of the core material with a hydrophilic outer shell material, and then adding at least a vinyl polymerizable monomer and a vinyl polymerizable initiator to an aqueous suspension of the precursor particles. A method for producing a capsulated toner for heat and pressure fixing, characterized in that the monomer component in the precursor particles is polymerized after being absorbed therein. 2. Encapsulation in which precursor particles are prepared by dispersing a core material constituting material and a hydrophilic outer shell material in an aqueous dispersion medium and coating the hydrophilic outer shell material on the surface of the core material by an in situ polymerization method. It is a particle, The manufacturing method of Claim 1 characterized by the above-mentioned. 3. 10 to 10 parts by weight of the precursor particles
3. The method according to claim 1, wherein the vinyl polymerizable monomer is used in a proportion of 200 parts by weight. 4. The method according to claim 1, 2 or 3, wherein the hydrophilic outer shell material is a shell material containing amorphous polyester as a main component. 5. The acid value of the amorphous polyester is 3 to 50K.
OH mg / g, The manufacturing method of Claim 4 characterized by the above-mentioned. 6. The production method according to claim 1, wherein a crosslinking agent is added to the aqueous suspension of the precursor particles and the mixture is reacted. 7. The method of preparing a precursor particle, wherein a crosslinking agent is added and reacted, and a crosslinking agent is further added to the obtained aqueous suspension of the precursor particle to react. ~ The method according to any one of 5 to 5. 8. The method according to claim 1, wherein a hydrophilic outer shell material is further added to the aqueous suspension of the precursor particles. 9. A heat-and-pressure fixing capsule toner comprising a heat-fusible core material containing at least a thermoplastic resin and a colorant, and an outer shell provided so as to cover the surface of the core material. The outer shell material is coated on the surface of the core material to form precursor particles, and then at least a vinyl polymerizable monomer and a vinyl polymerization initiator are added to an aqueous suspension of the precursor particles so that the precursor particles are absorbed. And then obtained by polymerizing the monomer component in the precursor particles, and a heat and pressure fixing capsule toner. 10. The heat and pressure fixing capsule toner according to claim 9, wherein the hydrophilic outer shell material is a shell material containing amorphous polyester as a main component. 11. The capsule toner for thermal pressure fixing according to claim 10, wherein the amorphous polyester has a glass transition point of 50 to 80 ° C. 12. The acid value of the amorphous polyester is 3 to 50.
The capsule toner for heat and pressure fixing according to claim 10 or 11, which has a KOH mg / g. 13. A glass transition point derived from a thermoplastic resin as a main component of a core material in an encapsulated toner is 10 to 50 ° C.
The capsule toner for heat and pressure fixing according to any one of claims 9 to 12, wherein 14. The capsule toner for heat and pressure fixing according to claim 9, wherein the precursor particles are obtained by using 3 to 50 parts by weight of the hydrophilic outer shell material with respect to 100 parts by weight of the core material. . 15. The heat and pressure fixing capsule toner according to claim 9, which is obtained by adding a crosslinking agent to an aqueous suspension of precursor particles and reacting them. 16. When the precursor particles are prepared, a cross-linking agent is added and reacted, and at the same time, a cross-linking agent is further added to an aqueous suspension of the precursor particles to be obtained and reacted. The capsule toner for heat and pressure fixing according to any one of claims 9 to 14. 17. The heat and pressure fixing capsule toner according to claim 9, further comprising a hydrophilic outer shell material added to the aqueous suspension of the precursor particles.