JPS58100855A - Capsulated toner - Google Patents

Abstract

PURPOSE:To prevent an offsetting phenomenon by forming a capsulated toner for pressure fixing with grafted carbon black as the core substance, a binder and a specified resin as the material of the shell which is formed around the core substance. CONSTITUTION:Polystyrene-grafted carbon black is used as the core substance of a capsulated toner for recordong by converting a latent image on an electrophotographic receptor into a visible image, and the toner is formed with the grafted carbon black kneaded with DBP as the core substance and polyurethane resin or polyurea resin as the material of the shell which is formed around the core substance. By mixing 5pts.wt. of the capsulated toner with 95pts.wt. iron powder as a carrier, a developer is obtd. The developer is patternwise transferred on prescribed paper and pressure fixed by means of a roller to obtain a high-quality image without causing an offsetting phenomenon.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a toner used for converting a latent image formed in an electric or magnetic recording method such as electrophotography or magnetic recording method into a visible image. It is. More specifically, the present invention relates to capsule toners used for these applications.

Various electrical or magnetic recording methods are known, such as electrophotography, electrostatic recording, or magnetic recording. What they have in common is that a latent image formed electrically or magnetically is converted into a visible image using a toner containing a display recording material such as a colorant in the form of a powder or a dispersed layer, and this is transferred to a transfer paper or other material. Transfer and fix onto the medium,
The point is to make it a duplicate image.

In order to turn a latent image into a visible image using toner, it is generally necessary to use a developer consisting of carrier particles and toner, or a developer consisting only of toner, and an electric or magnetic force that acts between the latent image and the latent image. A method is used in which a toner image is formed on the latent image by attracting toner to the latent image using an attractive force, and the latent image is developed into a visible image. Here, the former development method using a developer consisting of carrier particles and toner is called a two-component development method, and the latter development method using a developer consisting only of toner is called a one-component development method. ing.

The toner image formed on the latent image is then transferred onto a medium such as transfer paper and fixed onto the medium. There are three known methods for fixing toner images on media such as transfer paper: heat fixing, solvent fixing, and pressure fixing. The present invention provides a method for manufacturing.

Pressure fusing methods, in which toner particles are fused onto a media by applying pressure to the toner particles transferred onto the media, are described in US Pat. No. 3,289,528. Since this method does not use heat or solvent, it does not suffer from the various problems associated with methods such as heat fixing or solvent fixing, and the access time is fast, making it compatible with high-speed fixing methods. It inherently has various advantages.

However, the pressure fixing method has poor fixing properties compared to fixing methods such as heat fixing, the fixed image is easily peeled off when rubbed, and it requires considerably high pressure for fixing, so it cannot be used with media such as transfer paper. Fatigue of the media tends to occur due to breakage of the fibers of the media, the surface of the media tends to become excessively glossy, and there are limits to miniaturization of the pressure rollers used to apply high pressure. Therefore, there are problems in that miniaturization of the entire copying apparatus is restricted.

In order to solve the above-mentioned problems associated with the pressure fixing method, capsule toner in which toner is contained in microcapsules has already been developed. Capsule toner is a toner in the form of microcapsules obtained by forming an outer shell around a core material containing a display recording material such as carbon black, which has the property of being destroyed by the application of pressure. Capsule toner is said to be a toner suitable for the pressure fixing method because it does not require high pressure for fixing and has excellent fixing properties. It cannot be said that the various properties that are originally needed are necessarily satisfactory.

That is, for example, a toner used as a developer for dry electrophotography has good powder characteristics, excellent development performance, and WI
It is necessary that the surface of the photoreceptor, which is the surface on which the image is formed, is not contaminated, and in the case of a two-component development method, it is necessary that the surface of the carrier particles used is not contaminated. be done. In addition, the toner used in the pressure fixing method must have good pressure fixing properties and be unlikely to cause an offset phenomenon (a phenomenon in which the toner adheres to the surface of the pressure roller) to the pressure roller used for pressure fixing. Is required.

However, the capsule toners known so far have not always been satisfactory for the above-mentioned properties.

Among these objects, the primary object of the present invention is to provide a capsule toner that is particularly improved in pressure fixing properties.

Another object of the present invention is to provide a capsule toner that is improved not only in pressure fixing properties but also in offset properties.

Furthermore, the present invention provides a capsule toner that has improved pressure fixing properties and offset properties, and also exhibits excellent properties such as not being destroyed by impact within a developing device but easily being destroyed only at the pressure fixing position. Also,
That is the purpose.

As a result of intensive research to achieve the above-mentioned object, the present inventors have discovered that 1. By using grafted carbon black instead of carbon black, which has been commonly used as a display recording material, It has been found that the above objects can be achieved by using specific materials as the shell material of the capsule.

Therefore, the present invention provides a capsule toner comprising a core material containing a display recording material made of grafted carbon black and a binder, and an outer shell formed around the core material. It is.

Next, the present invention will be explained in detail.

Methods for preparing microcapsules by forming an outer shell around a core material containing a display recording material and a binder in a liquid medium are already known, and these methods can also be used to produce the capsule toner of the present invention. Known methods can be used.

An example of a method for producing microcapsules that can be used in the present invention is an interfacial polymerization method.

Other examples of methods for producing microcapsules that can be used in the present invention include internal polymerization method, phase separation method,
External polymerization method, melt dispersion cooling method, and core cell page binding method can be mentioned.

Note that the method for manufacturing microcapsules that can be used in the present invention is not limited to those exemplified above, and other methods for manufacturing microcapsules can also be used. Moreover, these various methods can also be used in combination.

Among examples of methods for producing microcapsules, a preferred method for the present invention is an interfacial polymerization method.

Among these, the following method is particularly preferable.

First, prepare substances A and B that have the following properties.

Substance A: A hydrophobic liquid itself, or a substance that dissolves or disperses well in a hydrophobic liquid.

Substance B: A substance that is either a hydrophilic liquid itself or has the property of dissolving or dispersing well in a hydrophilic liquid.

Substances A and B react with each other to form polyurethane resins, polyamide resins, polyester resins, polysulfonamide resins, polyurea resins, epoxy resins, and polysulfanate resins that are insoluble in both the wood-philic liquid and the hydrophobic liquid. or polycarbonate resin.

Next, the hydrophilic liquid and the hydrophobic liquid are separated by a method such as dispersing the hydrophobic liquid consisting of the A substance and the core substance into microdroplets in the woody liquid containing the B substance and then heating. By reacting both at the interface, polyurethane resin, polyamide resin, polyester resin, polysulfonamide resin, polyurea, which is insoluble in both the hydrophilic liquid and the hydrophobic liquid, is formed around the hydrophobic liquid consisting of substance A and the core substance. Microcapsules containing a core material with an outer shell made of resin, epoxy resin, polysulfanate resin, or polycarbonate resin (i.e.,
Prepare a dispersion liquid in which capsule toner) is dispersed.

In the present invention, a particularly preferred combination of substance A and substance B is such that a polyurethane resin or polyurea resin is formed by the reaction of both substances.

Examples of substances A suitable for such combinations include the following compounds containing incyanato or isothiocyanato groups.

(1) Diisocyanate m-phenylene diisocyanate, p-phenylene diisocyanate, 2.6-dolylene diisocyanate, 2
．． 4-) Lylene diisocyanate, naphthalene-1,4
-diisocyanate, diphenylmethane-4,41-diisocyanate, 3,3'-dimethoxy-4,4°-biphenyl diisocyanate, 3,3'-dimethyldiphenylmethane-4,4'-diincyanate, xylylene-1 , 4-diisocyanate, xylylene-1゜3-diisocyanate, 4.4゛-diphenylpropane diisocyanate, trimethylene diisocyanate, hexamethylene diisocyanate, propylene-1,2-diisocyanate, Butylene-1,2-diisocyanate, ethyridine diisocyanate', cyclohexylene-1,
2-diisocyanate, cyclohexylene-1,4-diisocyanate, tolylene diisocyanate, triphenylmethane diisocyanate.

(2) Triisocyanate 4.4',4''-)liphenylmethane triisocyanate, polymethylene polyphenylisocyanate.

(3) Tetraisocyanate 4.4'-dimethyldiphenylmethane-2°2', 5.
5'-Tetraisocyanate.

(4) Polyincyanate prepolymer adduct of hexamethylene diisocyanate and hexanetriol, 2.
4-1 Adduct of lylene diisocyanate and catechol,
Adducts of tolylene diisocyanate and hexanetriol, adducts of tolylene diisocyanate and trimethylolpropane, adducts of xylylene diisocyanate and trimethylolpropane.

(5) Diisothiocyanate tetramethylene dithiocyanate, hexamethylene diisothiocyanate, p-phenylene dithiocyanate, xylylene-1,4-diisothiocyanate,
Ethyridine dithiocyanate.

Similarly, examples of the B substance suitable for such a combination include the following compounds.

1 (1) water (2) polyol and polythiol ethylene glycol, l, 4-butanediol, cate,
Cole, resorcinol, hydroquinone, 1.2-dihydroxy-4-methylbenzene, 1.3-dihydroxy-5-methylbenzene, 3.4-dihydroxy-1-
Methylbenzene, 3゜5-dihydroxy-1-methylbenzene, 2.4-dihydroxy-1-ethylbenzene,
1.3-naphthalene diol, 1.5-naphthalene diol, 2.3-naphthalene diol, 2.7-naphthalene diol, polythiol (3) Polyamine ethylene diamine, tetramethylene diamine, pentamethylene diamine, hexamethylene diamine, P-phenylene diol Diarmine 1m-phenylenediamine, 2-hydroxytrimethylenediamine, diethylenetriamine, triethylenetetraamine, diethylaminopropylamine, tetraethylenepentamine, adduct of epoxy compound and amine.

(4) PiperazinePiperazine, 2-methylbiperazine, 2,5-dimethylpiperazine.

Furthermore, in the above combination of A substance and B substance, A
The substances can also be replaced by acid chlorides, sulfonyl chlorides or bischloroformates, such as those exemplified below.

(1) Acid chloride oxazoloyl chloride, succinoyl chloride,
Adipoyl chloride, sebacoyl chloride, phthaloyl chloride, inphthaloyl chloride, terephthaloyl chloride, fumaroyl chloride, 1,4-cyclohexane dicarbonyl chloride, polyester with acid chloride functional group, acid chloride functional group Polyamide with.

(2) Sulfonyl chloride 1,3-benzenedisulfonyl chloride, 1,4-benzenedisulfonyl chloride, 1,5-naphthalenedisulfonyl chloride, 2,7-naphthalenedisulfonyl chloride, p,p'-monooxybis(benzene disulfonyl chloride), 1,6-hexanedisulfonyl chloride.

(3) Bischloroformate ethylene bis(chloroformate), tetramethylene bis(chloroformate), 2,2'-dimethyl-1,3
-Propane bis(chloroformate), p-propane bis(chloroformate).

Furthermore, when dispersing a hydrophobic liquid consisting of substance A and a core substance into microdroplets in a hydrophilic liquid containing substance B,
It is preferable to mix a low boiling point solvent or a polar solvent with the hydrophobic liquid consisting of the substance and the core substance. These low boiling point solvents or polar solvents contribute to promoting the formation of an outer shell, which is a reaction product between substance A and substance B. Examples of low-boiling or polar solvents that can be used for such purposes include methyl alcohol, ethyl alcohol,
Ethyl ether, tetrahydrofuran, dioxane, methyl acetate, ethyl acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, n-pentane, n-hexane, benzene, petroleum ether, chloroform, carbon tetrachloride, methylene chloride, ethylene chloride, disulfide Examples include carbon, dimethylformamide, and the like.

The core material used in the present invention is one containing grafted carbon black as a display recording material for converting a latent image into a visible image.

In the present invention, grafted carbon refers to carbon black particles in which a polymer group is irreversibly bonded to the surface of the particles. In order to bond a polymer group to the carbon black surface, for example, (1) a method of growing a polymer chain at the polymerization initiation site of the carbon black particle surface, (2) a method of adding a low molecular compound to the carbon black particle surface in advance, (3) A method in which the polymer chains being polymerized in a continuous phase are transferred to the active region on the surface of the carbon black particles. These methods are described in J. B. Donnet & A.

Voet: Carbon Black, Mars
l Dekker, Inc. (1976) [Translator:
Carbon Black, J. B., Donne A.

Detailed information can be found in the book written by John Poet and published by Kodansha.

Preferred grafted carbon blacks used in the present invention include polystyrene-grafted carbon black, polyisoprene-blatted carbon black, polymethyl methacrylate-grafted carbon black, polyethyl methacrylate-grafted carbon black, and polymethyl ethacrylate-grafted carbon black. Mention may be made of carbon black, polyethyl ethacrylate-grafted carbon black, and poly-N-vinylcarbazole-grafted carbon black.

The amount of grafted carbon black used in the present invention to be added to the core material can be determined in accordance with the amount of conventionally known ordinary carbon black added to the core material. In addition, if desired, out of the total amount of grafted carbon black contained in the core material of the capsule toner of the present invention,
Less than 50% by weight can also be replaced by conventional carbon black.

The binder used in the present invention disperses and holds the display recording material in the core material, and when transferring the visible image made of the display recording material formed on the latent image to a medium such as copy paper. It functions to fix the image on the medium. Therefore, as pine and goo, conventionally,
High boiling point organic solvents that are used or proposed to be used when finely dispersing oil-soluble photographic additives in an aqueous medium and incorporating them into silver halide color photographic materials, or conventional pressure fixing agents. It is preferable to use a polymer that has been used or studied as a binder for inclusion in the core material of a capsule toner.

Examples of such high boiling point organic solvents include the following compounds.

(1) Phthalate esters dibutyl phthalate, dioctyl phthalate, dioctyl phthalate, dioctyl phthalate.

Dinonyl phthalate, didecyl phthalate, butylphthalyl butyl glycolate, dibutyl monochlorophthalate.

(2) Phosphate esters tricresyl phosphate, tricresyl phosphate, tris(isopropylphenyl) phosphate, tributyl phosphate, trihexyl phosphate, trioctyl phosphate, trinonyl phosphate, tridecyl phosphate, trioleyl phosphate, tris(butoxy) ethyl) phosphate, tris(chlorethyl) phosphate, tris(dichloropropyl)bosphate.

(3) Citric acid esters 0-acetyl triethyl citrate, 0-acetyl tributyl citrate, 0-acetyl trihexyl citrate, 0-acetyl trioctyl citrate, 0-acetyl trinonyl citrate, O-acetyl tride Sil citrate, triethyl citrate, tributyl citrate, trihexyl citrate, trioctyl citrate,
Trinonyl citrate, tridecyl citrate.

(4) Benzoic acid esters butyl benzoate, hexyl benzoate, heptyl benzoate, octyl benzoate, nonyl benzoate, decyl benzoate, dodecyl benzoate, tridecyl benzoate, tetradecyl benzoate, hexadecyl benzoate, octadecyl benzoate,
Oleyl benzoate, pentyl 0-methylbenzoate, decyl p-methylbenzoate, octyl 0-chlorobenzoate, lauryl p-chlorobenzoate, propyl 2,4-dichlorobenzoate, octyl 2,4
-dichlorobenzoate, stearyl 2.4-dichlorobenzoate, oleyl 2.4-dichlorobenzoate, octyl p-methoxybenzoate.

(5) Fatty acid esters hexadecyl myristate, dibutoxyethyl succinate, dioctyl adipate, dioctyl azelate,
Decamethylene-1,10-diol, diacetate, triacetin, tributin, benzyl caprate, pentaerythritol tetracapronate, isosorbite cyacrylate/(6) Amides N, N-dimethyl lauramide, N, N-diethyl Caprylamide, N-butylbenzenesulfonamide.

(7) Others Trioctyl trimellitate, chlorinated paraffin.

In addition, for examples of the above-mentioned high-boiling point solvents and other high-boiling point solvents that can be used in the present invention, 1.
For example, it is described in the following patent publications:

JP 4B-23233, JP 49-29481: JP 47-1031, JP 50-1121332, JP 50-82078, JP 51-28035, JP 5l-
2f10313, 51-28037, 51-2
No. 7921, No. 51-2713/22: U.S. Patent No. 2
, No. 322,027, No. 2,353,282, No. 2,533,514, No. 2,835.5713,
2.85.

2.383, 3,287,134, 3,5
No. 54,755, No. 3,8711,137, No. 3
, 876.142, 3°700.454, 3,748,141, 3,837,863, 3.11138.303: British Patent No. 958.441; Same No. 1,222,753
No. 2 West German Open Gazette (OLS) No. 2,538,889.

Preferred examples of polymers that can be used in the present invention include the following compounds; however, it is desirable that these polymers used in the present invention have a low molecular weight.

polyolefin, olefin polymer, styrene resin,
Epoxy resin, polyester, rubber, polyvinylpyrrolidone, polyamide, coumaron-indene copolymer, methyl vinyl ether-containing maleic anhydride copolymer, maleic acid-modified phenolic resin, phenol-modified terpene resin, silicone resin, epoxy-modified phenolic resin, natural Resin-modified phenolic resin, amino resin, polyurethane, polyurea, copolymer oligomer of acrylic acid and long-chain alkyl methacrylate, polystyrene, polyvinyl acetate, polyvinyl chloride.

Further, examples of the above-mentioned polymers and other polymers that can be used in the present invention are described in, for example, the following patent publications.

JP 413-1588, JP 54-8104: JP 48-75032, JP 4B-78931, JP 48
-17739, 51-132838, 52-1
No. 18531, No. 52-108134, No. 52-11
No. 9937, No. 53-1028, No. 53-38243
No. 53-118049, No. 55-8!11854
No. 55-11113855: U.S. Patent No. 3,893,933.

The binder used in the present invention has conventionally been used when an oil-soluble photographic additive is finely dispersed in an aqueous medium and incorporated into a silver halide color photosensitive material. It is also possible to use polymers that have been described in the art, and such polymers are described, for example, in Japanese Patent Publication No. 48-30494.

In the present invention, the binder may be one of the various high-boiling organic solvents or polymers described above, or may be a mixture of any compound in any proportion.

The core material of the capsule toner produced according to the present invention contains the display recording material and the binder as described above, but it can also contain various additive materials as desired. Examples of such additive substances include mold release agents such as fluorocarbon resins, and metal elements, alloys, or metal compounds such as cobalt, iron, and nickel for producing toners used in -component development systems. Mention may be made of magnetic particles.

On the other hand, the outer shell of the capsule toner produced according to the present invention is made of a polymer or high molecular substance, and if desired, this outer shell may also be coated with a metal-containing dye, a charge control agent such as nigrosine, or hydrophobic silica. Glidants such as, or any other additives may be added.

These additive substances can be incorporated into the outer shell of the capsule toner at any time, such as when the outer shell is formed, after the capsule toner is separated and dried, or after the heat treatment according to the present invention.

After preparing microcapsules by forming an outer shell around a core material containing a display recording material and a binder in a liquid medium, the microcapsules are separated from the liquid phase and dried. This separation and drying operation is usually carried out by spray drying a dispersion containing microcapsules.

In the present invention, it is desirable that the microcapsules separated and dried by the method described above are then subjected to heat treatment.This heat treatment further improves the powder properties of the capsule toner of the present invention. -300℃
Preferably, the temperature is in the range of 80-
It is particularly preferred to heat at a temperature in the range of 150" O. The heating time will vary depending on the heating temperature and the type of binder used, but will usually be selected from the range of 10 minutes to 48 hours, more typically 2. - Selected from the range of 24 hours.

There are no particular restrictions on the equipment and instruments used for the heat treatment; for example, any heat drying equipment and heat drying equipment such as an electric furnace, Matsufuru furnace, photoplate, electric dryer, fluidized bed dryer, infrared dryer, etc. Can be used.

Next, Examples and Comparative Examples of the present invention will be shown.

[Example 1] Polystyrene graft, carbon black 2.5g
A primary liquid was prepared by mixing 18 g of a mixed solvent consisting of 4 g of 1,4-naphthalidiol and 12 g of tetrahydrofuran with 25 g of a dispersion in which 22.5 g of dibutyl phthalate was dispersed. To the mixture, 6 g of diphenylmethane-4,4'-diisocyanate and 0.05 g of N-ethylmorpholine as a catalyst were added at room temperature to prepare a secondary liquid.

Separately, dissolve 1 g of gum arabic in 19 g of water at 20°C,
While vigorously stirring this solution, the above-mentioned secondary liquid was gradually poured into it to obtain an oil-in-water emulsion having an average oil droplet diameter of 1θ to 20.

This operation was carried out while cooling the area around the container so that the temperature of the emulsion did not exceed 30°C.

After emulsion formation is complete, loosen the stirring and add 70%
70 g of warm water at 10°C was added, and then the temperature of the emulsion was gradually increased to 80°C over 10 minutes. The emulsion was maintained at this temperature for an additional 30 minutes with continued stirring to complete the encapsulation. Next, this microcapsule dispersion was centrifuged at 5000 rpfit to separate the microcapsules and the gum arabic aqueous solution, thereby obtaining a microcapsule slurry from which the gum arabic was removed.

100 cc of water was added to this microcapsule slurry and dried in a spray dryer to obtain a powdered capsule toner. Next, this capsule toner was subjected to heat treatment at 110° C. using an infrared dryer.

The capsule toner obtained above was evaluated by the following method.

A developer was prepared by thoroughly mixing 5 parts by weight of capsule toner and 85 parts by weight of iron powder carrier using a shaker. When the state of the capsule toner after mixing with the carrier was similarly observed under a microscope, no broken capsules were found.

Next, the electrostatic latent image formed by a conventional electrophotographic method was developed with the above developer to form a toner image, and the toner image was transferred to transfer paper to obtain a visible image. When this visible image was fixed under pressure using a pressure fixing roller at a pressure of 350 kg/crn', a copied image with good fixability and high sharpness was obtained. Even when the surface of the copied image was rubbed with a finger, there was almost no change in the image. In addition, almost no toner adhered to the roller.

[Example 2-6] In Example 1, polymethyl methacrylate-grafted carbon black, polymethacrylic ethyl methacrylate-grafted carbon black, polymethyl ethacrylate-grafted carbon black, Polyethyl ethacrylate grafted carbon black, and polyN-
Similar operations were performed using each of the vinyl carbazole grafted carbon blacks to obtain five types of capsule toners.

Example 1 using each of these five types of capsule toners
When the images were transferred to transfer paper and fixed under pressure in the same manner as described above, a copied image with good fixability and high sharpness was obtained by pressure fixing operation using any of the capsule toners. Even when the surface of each copy image was rubbed with a finger, there was almost no change in the image. Further, in all cases, almost no toner adhered to the roller.

[Comparative Example 1] A capsule toner was obtained by carrying out the same operation as in Example 1 but using ordinary carbon black instead of the polystyrene-grafted carpump stick.

When this capsule toner was transferred to transfer paper and fixed under pressure in the same manner as in Example 1, a copied image was obtained that lacked sharpness in some parts. When the surface of the copied image was rubbed with a finger, the carbon black was easily peeled off and the image became extremely dirty. Additionally, toner adhesion to the roller occurred partially.

[Example 7] 1 g of polyisoprene grafted carbon black)
A primary liquid was prepared by dispersing the mixture in 13 cc of tricresyl phosphate and dissolving 1 g of toluleylene diisocyanate/hexanetriol addition compound therein.

Separately, a secondary liquid was prepared by adding 7 g of polyvinyl alcohol to 100 cc of water. The primary liquid was added dropwise to the secondary liquid while stirring to form an emulsion in the form of microdroplets, and then the emulsion was maintained at room temperature for about 2 hours, and then the liquid temperature was raised to 8000°C and the emulsion was maintained for about 1 hour. Ta.

- The toluylene diisocyanate/hexanetriol addition compound contained in the primary liquid reacted with water to form a film around the microdroplets of the primary liquid. 100 cc of water was added to the microcapsule slurry thus obtained and spray-dried to obtain a powdered capsule toner. Next, this capsule toner is dried using an infrared dryer.
Heat treatment was performed at 10°C.

Next, the strength and pressure fixing properties of the outer shell of the capsule toner obtained above were examined in the same manner as in Example 1, and it was found that this capsule toner did not break even when mixed with a carrier, and was not fixed well. A copy image with good quality and high sharpness was obtained. Even when the surface of the copied image was rubbed with a finger, there was almost no change in the image. Furthermore, almost no toner adhered to the pressure fixing roller.

[Comparative Example 2] A capsule toner was obtained by carrying out the same operation as in Example 2 but using ordinary carbon black instead of polyisoprene grafted carbon black.

When this capsule toner was transferred to transfer paper and fixed under pressure in the same manner as in Example 1, a copied image was obtained that lacked sharpness in some parts. When the surface of the copied image was rubbed with a finger, the carbon black was easily peeled off and one image was significantly stained. Additionally, toner adhesion to the roller occurred partially.

Patent applicant Fuji Photo Film Co., Ltd. Agent
Patent attorney Yasuo Yanagawa 519-

Claims (1)

[Claims] 1. A capsule toner comprising a core material containing a display recording material made of glazed carbon black and a binder, and an outer shell formed around the core material. . 2゜Grafted carbon black includes polystyrene grafted carbon black, polyisoprene grafted carbon black, polymethyl methacrylate grafted carbon black, polyethyl methacrylate grafted carbon black, polymethyl ethacrylate grafted carbon black, and polyethyl ethyl methacrylate. The capsule toner according to claim 1, wherein the capsule toner is selected from the group consisting of grafted carbon black and poly-N-vinylcarbazole grafted carbon black. 36 The material of the outer shell formed around the core material is polyurethane resin, polyamide resin, polyester resin, polysulfonamide resin, polyurea resin, epoxy resin, polysulfanate resin, or polycarbonate resin. A capsule toner according to claim 1. 2. The capsule toner according to claim 1, wherein the material of the outer shell formed around the 4° core material is either polyurethane resin or polyurea resin.