JPH0752306B2 - Capsule toner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention can be visualized by an electric latent image method such as an electrophotographic method, an electrostatic printing method, an electrostatic recording method or a magnetic latent image method by a magnetic recording method. The present invention relates to a capsule toner for forming an image, and more specifically to a capsule toner that can be suitably used as a pressure fixing type toner.

[Prior art and its problems]

In recent years, electric latent images and magnetic latent images are formed by electrophotography, electrostatic printing, electrostatic recording, magnetic recording, etc., developed with toner of a developer, and transferred to transfer paper, It is fixed and a visible image is formed.

As a method for fixing a toner image on a medium such as the transfer paper, generally, there are known three kinds of fixing methods, that is, a heat fixing method using heating, a solvent fixing method using a solvent, and a pressure fixing method using pressure. .

The heat fixing method and the solvent fixing method have better fixability than the pressure fixing method, but various troubles are likely to occur due to heat, solvent, etc., and the access time is also slow, which hinders high-speed fixing. .

On the other hand, the pressure fixing method does not use heat or solvent, so various obstacles associated with heat and solvent do not occur, the access time is fast, and high-speed fixing is possible. However, there is a drawback that a high pressure must be applied in order to increase the fixing power, and therefore the high pressure lowers the strength of the paper and the surface gloss becomes excessive.

For this reason, capsule toners in which toner is enclosed in microcapsules have also been studied and developed, but conventionally known capsule toners have the powder characteristics originally required as toners and the fixability to a transfer medium. It was not always satisfactory.

[Object of the Invention]

The present invention has been made to solve various problems in the pressure fixing method described above, and provides a capsule toner that is not easily affected by humidity, has excellent powder characteristics and storage stability, and can be fixed at a low pressure. That is the purpose.

[Means for solving problems]

The capsule toner of the present invention is a capsule toner comprising a core substance containing a display recording material and a solvent, and an outer shell formed around the core substance, and the core substance contains an unsaturated compound having an iodine value of 100 or less. As a result, it is possible to obtain a capsule toner that can be satisfactorily fixed at a low pressure, and that has excellent powder characteristics and storage stability.

[Preferred embodiment]

As the display recording material in the capsule toner of the present invention, known dyes and pigments conventionally used in heating, solvent and pressure fixing methods can be used.

For example, various carbon black, aniline black,
Examples thereof include naphthol yellow, rhodamine lake, methyl violet lake, phthalocyanine blue, quinoline yellow and the like.

When the capsule toner of the present invention is used as a magnetic toner, the core substance contains magnetic elements such as iron, cobalt, nickel and manganese, and magnetic powders such as magnetite and ferrite containing these, alloys and compounds containing these. It is a thing.

The core substance solvent in the present invention is preferably a hydrophobic solvent having a boiling point of 100 to 200 ° C., cyclohexanone,
Aliphatic hydrocarbon solvents such as methylcyclohexanone, methylcyclohexane, phenylcyclohexane, bicyclohexyl, mineral spirits, paraffin hydrocarbon solvents having 8 or more carbon atoms; toluene, xylene, amylbenzene, amyltoluene, diamyltoluene, diphenylethane, Aromatic hydrocarbon solvents such as tetralin, decalin, ethylbenzene, diethylbenzene, triethylbenzene, cumene, cymen, hydrogenated petroleum naphtha; perchlorethylene, hexachloroethane, dichlorobutane, hexachloropropylene, hexachlorobutadiene, 2-ethylhexyl chloride. , Chlorobenzene, dichlorobenzene, trichlorobenzene, chlorotoluene,
Halogenated hydrocarbons such as; ketones such as methylhexyl ketone, valerone; etc .; ethers such as amyl ether, hexyl ether, butyl phenyl ether, butyl cellosolve, benzyl cellosolve, ethylhexyl cellosolve; amyl acetate, methylamyl acetate, acetic acid-2- Ethylbutyl, 2-ethylhexyl acetate, cyclohexyl acetate, methylcyclohexyl acetate, phenyl acetate, benzyl acetate, butyl carbitol acetate, methoxybutyl acetate, propyl propionate, butyl propionate, isobutyl propionate, ethyl butyrate, butyl butyrate, isoamyl butyrate. , Butyl oxalate, ethyl crotonate, benzyl benzoate, and other plasticizers such as esters can be used.

A particularly important point when selecting a solvent is to select a solvent that satisfies both the retention of the encapsulated ink and the sharp particle size in emulsification.

In the present invention, dispersion of the core substance, dissolution, by making a mixture containing one or more of each of the solvents and plasticizers having a boiling point of 100 ~ 200 ℃ as a solvent for adjusting the viscosity of the encapsulated ink It was found that both retentivity and sharp particle size in emulsification can be satisfied.

Further, in the present invention, if a plasticizer for dispersing, dissolving, and adjusting the viscosity of the core substance is used together with the solvent for the core substance, the particle size distribution is excellent and a uniform capsule toner can be obtained. , Phosphate esters such as tryptyl phosphate, tri-2-ethylhexyl phosphate, tricresyl phosphate; dimethyl phthalate, diethyl phthalate,
Dibutyl phthalate, di-n-octyl phthalate, diisooctyl phthalate, dicapryl phthalate, di-phthalate
Phthalates such as 2-ethylhexyl, dioctyldecyl phthalate, diisodecyl phthalate, butylbenzyl phthalate and butoxyethyl phthalate; aliphatic monobasic acids such as butyl oleate, tetrahydrofurfuryl oleate and glycerin monooleate. Ester; dibutyl adipate, n-hexyl adipate, di-2-ethylhexyl adipate, di-2-ethylbutyl azelate, di-2-ethylhexyl azelate, dibutyl sebacate, di-2-ethylhexyl sebacate, sebacin Aliphatic dibasic acid esters such as acid dicapryl; polyhydric alcohol esters such as triethylene glycol-di-2-ethylbutyrate and triethylene glycol-di-2-ethylhexoate; methyl acetylricinoleate, acetylri Nord butyl, acetyl ricinoleate methoxyethyl, butyl phthalyl butyl glycolate, tri-acetyl citrate (2-ethylhexyl)
And the like; chlorinated paraffin, chlorinated biphenyl, dinonylnaphthalene, o- and p-toluenesulfone ethylamide, methyl abietic acid and the like.

Furthermore, in the present invention, by encapsulating an unsaturated compound having an iodine value of 100 or less in a capsule, it is possible to further improve the fixability without causing curing development in the capsule. Hyresin # 60, # 75, # 90, QP as unsaturated compounds up to 100
A, QP, NX, 60MN, AX, Corporex # 2100, DRA-100P
(Both products are manufactured by Toho Petroleum Resin Co., Ltd.) Castor oil, coconut oil and the like can be mentioned.

Next, in order to produce the encapsulated toner of the present invention, the interfacial polymerization method, in situ method, coacervation method, submerged curing coating method (orifice method), submerged liquid method, which are known in the microcapsule production technology, are used. Although methods such as a drying method and a spraying / granulating method can be used, particularly in the interfacial polymerization method, it is possible to produce a capsule toner that is not easily affected by humidity and has excellent powder characteristics and storage stability. Further, in the interfacial polymerization method, a polyurea resin, a polyurethane resin, a polyester resin is used as an outer shell of the capsule toner of the present invention made of a polymer material formed by using a reaction material such as a monomer or a low molecular weight prepolymer. , A polyamide resin and a composite material thereof are preferable, and a polyurea resin or a polyurethane resin and a composite material thereof are particularly preferable.

Further, a metal-containing material conventionally used for toner in a capsule outer shell resin, a charge control agent such as a nigrosine dye,
Various additives may be included to form the capsule shell.

〔Example〕

Examples of encapsulation of the encapsulated toner of the present invention will be shown below, but the method for obtaining the intended encapsulated toner is not necessarily limited to these.

Example 1 Preparation of encapsulation ink "EPT500" (trade name; magnetite manufactured by Toda Kogyo Co., Ltd.) 55
Parts, polyethylene wax (average molecular weight 3500) 5 parts,
5 parts of "AC-430" (trade name; ethylene vinegar vinyl copolymer manufactured by Allied Chemical Co., Ltd.), "Solvesso 100" (trade name: aromatic hydrocarbon manufactured by Exxon Chemical Co., distillation range; initial boiling point 164
℃, 5% 166 ℃, 10% 167 ℃, 50% 169 ℃, 90% 172 ℃, 95
% 174 ° C, dry point 176 ° C) 20 parts, dioctyl phthalate 10
5 parts of "COPOLEX # 2100" (trade name; unsaturated adhesive resin manufactured by Toho Petroleum Resin Co., iodine value 70) are kneaded with a triple roll.

248 g of ink prepared by emulsification and encapsulation was heated to 50 ° C, and "MR-200"
(Product name: Isocyanate made by Nippon Polyurethane Co.) 17.5
Add g and mix. 1400 g of 0.75% PVA solution is heated to 50 ° C., a mixture of ink and isocyanate is added, and the mixture is emulsified with an ultra homogenizer to a particle size of 5 to 25 μm. 121 g of water and diethylenetriamine were added to this emulsion.
5.7 g of the mixture is added and the encapsulation reaction is performed at room temperature for 10 hours.

The capsule toner dispersion obtained by washing and spray drying is allowed to stand, the supernatant is discarded, and water is newly added. This washing step is repeated 3 times, and 0.5 g of "DS-102" (trade name; fluorine-based surfactant manufactured by Daikin Industries, Ltd.) is added and spray-dried at an inlet temperature of 250 ° C and an outlet temperature of 80 ° C to obtain a capsule toner. Obtained.

Example 2 Preparation of encapsulated ink "EPT500" (trade name; magnetite manufactured by Toda Kogyo Co., Ltd.) 55
Part, "AC-430" (trade name; ethylene vinegar vinyl copolymer manufactured by Allied Chemical Co., Ltd.), 10 parts, "Solvesso 100" (trade name; aromatic hydrocarbon manufactured by Exxon Chemical Co., Ltd.), 10 parts dibutyl phthalate, "high resin"# 60 "(trade name; unsaturated adhesive resin manufactured by Toho Petroleum Resin Co., iodine value 80) is kneaded with a three-roll mill.

248 g of ink prepared by emulsification and encapsulation was heated to 50 ° C, and "MR-300"
(Product name: Isocyanate made by Nippon Polyurethane Co.) 17.5
Add g and mix well. 1400g of 0.75% PVA solution at 50 ℃
The temperature is raised to, the mixture of ink and isocyanate is added, and the mixture is emulsified with an ultra homogenizer to a particle size of 5 to 25 μm. 121g of water and "SP-200" in this emulsion
(Product name: Polyethyleneimine manufactured by Nippon Shokubai Chemical Co., Ltd.)
Add 5.5 g of the mixture and carry out the encapsulation reaction at room temperature for 10 hours.

Washing and Spray Drying Washing and spray drying were performed in the same manner as in Example 1 to obtain a capsule toner.

Example 3 Preparation of encapsulation ink "EPT-500" (trade name; magnetite manufactured by Toda Kogyo Co., Ltd.) 55
Part, "AC-430" 10 parts, "Solvesso 100" 20 parts, dibutyl phthalate 10 parts, "HIRESIN AX" (trade name; Toho Petroleum Resin Co., unsaturated adhesive resin, iodine value 50) 5 parts Is kneaded with three rolls.

248 g of ink prepared by emulsification and encapsulation was heated to 50 ° C, and 17.5 g of "M
R-200 "and 1 g of dibutyl phthalate are added with a solution of 1.4 g of chloradic terephthalate dissolved therein and mixed well. 0.75
% PVA solution (1400 g) is heated to 50 ° C., a mixed solution of ink and isocyanate is added, and emulsification is performed by an ultra homogenizer so that the particle size becomes 5 to 25 μm. Water in emulsion 12
A solution prepared by dissolving 1 g, 3.8 g of diethylenetriamine and 2.3 g of sodium carbonate is added, and the encapsulation reaction is performed at room temperature for 10 hours.

Washing and Spray Drying Washing and spray drying were performed in the same manner as in Example 1 to obtain a capsule toner.

Example 4 A capsulated toner was obtained in the same manner as in Example 3 except that castor oil (iodine value 90) was used instead of “High Resin AX” in Example 3.

Comparative Example 1 “Corporex # 2100” in Example 1 was replaced with “High Resin LR” (trade name; manufactured by Toho Petroleum Resin Co., unsaturated compound,
A capsule toner was obtained in the same manner as in Example 1 except that the iodine value was changed to 120).

Comparative Example 2 Capsule toner was obtained in the same manner as in Example 1 except that "Corporex # 2100" in Example 1 was replaced with safflower oil (iodine value 140).

Comparative Example 3 Capsule toner was obtained in the same manner as in Example 2 except that “Coporex # 2100” in Example 1 was replaced with linseed oil (iodine value 170).

Comparative Example 4 “Corporex # 2100” in Example 1 was replaced with “DRA-10
[0P] (trade name; liquid tackifier manufactured by Toho Petroleum Resin Co., Ltd.), and a capsule toner was obtained in the same manner as in Example 3.

Each of the capsule toners obtained in Examples 1 to 4 and Comparative Examples 1 to 4 was electrophotographic copying machine "CP-55N [manufactured by Kyocera Corporation].
Was used as a developer to develop an electrostatic charge image, and a visible image "solid black" was obtained by pressure fixing. This image was rubbed and fixed 25 times with a high-quality paper having a continuous weight of 55 kg by a paperboard abrasion tester manufactured by Kumagai Riki Kogyo Co., Ltd. The results are shown in Table 1.

In the table, the mark “◯” has a sufficient fixing property in practical use, and the mark “Δ” has a certain fixing property, but there is a problem in practical use. Further, X has extremely poor fixing property and is not practically used at all.

Ink rubbing stain test; "Solveso 200" (trade name; instead of "Solveso 100" in Example 1 and the capsule toner obtained in Example 1)
Exxon Chemical's aromatic hydrocarbons, distillation range; initial boiling point 23
1 ° C, 5% 234 ° C, 10% 237 ° C, 50% 244 ° C, 90% 260 ° C, 9
Using the capsule toner obtained in the same manner as in Example 1 using 5% 265 ° C. and dry point 276 ° C.), development was performed in the same manner as above and pressure fixing was performed to obtain a test paper. While using a paperboard abrasion resistance tester [Kumagaya Riki Kogyo Co., Ltd.], a test paper with a width of 20 mm and white fine paper (55 kg) are brought into contact with each other at a pressure of 500 g / 1.5 mm × 1.5 mm, It was reciprocated 50 times and rubbed, and the stain due to the toner transferred to the high-quality paper was judged by a sensory test. The results are shown in Table 2.

It can be seen from Table 2 that the use of a solvent having a boiling point of 200 ° C. or higher (Solvesso 200) is not preferable because the ink stains greatly after the toner is fixed on the paper.

[Effects of the Invention] As can be understood from Table 1, the encapsulated toner of the present invention is extremely excellent in fixing performance at low pressure. In addition, it is excellent in storage stability and powder characteristics without being affected by humidity, which is a very useful invention in industry.

Claims (2)

[Claims] 1. A core substance containing a display recording material and a solvent,
A capsule toner comprising an outer shell formed around a core substance, wherein the solvent is a solvent having a boiling point of 100 to 200 ° C., and the core substance contains an unsaturated compound having an iodine value of 100 or less. Capsule toner to be used. 2. The capsule toner according to claim 1, wherein the core substance solvent of the capsule toner contains one or more kinds of each of a plasticizer and a solvent having a boiling point of 100 to 200 ° C.