JPS60222869A - Microcapsule type toner - Google Patents

Abstract

PURPOSE:To obtain a toner which is provided with resilience to an outside wall and is provided with fixing ability to the outside wall itself by using an epoxy urea resin or epoxy urethane resin obtd. by using respectively >=1 kind of bifunctional isocyanate and tri- or higher functional isocyanate. CONSTITUTION:A core material contg. a pressure fixable material is coated by the outside wall consisting essentially of the epoxy urea resin or epoxy urethane resin obtd. by bringing bisphenol, an epoxy resin such as A type epoxy resin, novolak type epoxy resin or epoxylated soybean oil, the mixture composed of the bifunctional isocyanate and tri- and higher functional isocyanate and the polyol or amine which reacts with the epoxy group into reaction, thereby producing the microcapsule type tone. The toner which has excellent pressure fixability, obviates flocculating and blocking during storage and has good electrifying property and excellent fluidity is thus obtd.

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a toner for developing electrostatic images, and more particularly to a microcapsule type toner that can be suitably used as a pressure fixing type toner. .

[Prior art]

In recent years, electrophotographic methods, electrostatic printing methods, electrostatic recording methods, etc. are used to form an electrostatic charge image based on image information, and this is developed with a developer toner to form a toner image. It is widely practiced to form a visible image by transferring the image to a transfer paper or the like and then fixing it.

Conventionally, as a toner for developing electrostatic images, a powdered toner obtained by finely pulverizing a thermoplastic resin as a binder and a coloring agent such as carbon black dispersed therein has been widely used.

If it is a two-component toner, it is mixed and stirred with a carrier such as iron powder or glass beads, or if it is a one-component toner containing fine magnetic powder, it is stirred itself. The toner image is triboelectrically charged, an electrostatic charge image is developed using the electrostatic force, and the resulting toner image is transferred, for example, and then heated and fixed using a heating roller or the like. However, in such toners, during agitation for triboelectric charging, the gutter particles are crushed and fine toner particles are generated, resulting in poor visible image quality or the need to replace the toner with new ones prematurely. Not only is this necessary, but since fusing is achieved using a heat fusing method, a long waiting time is required until the temperature of the fusing device rises to the required set temperature, and the heating This requires a large amount of energy and can even cause a fire if a paper jam occurs. Moreover, in order to achieve reliable fixing, it is necessary to satisfy quite strict conditions such as temperature conditions.

Under these circumstances, a pressure fixing method has been proposed. That is, pressure fixing methods have been proposed in which toner particles are fixed to an image forming support by applying pressure to the toner; for example, the method described in U.S. Pat. No. 3,269,626 is known. There is. This method has the advantage that it does not require the use of heat or solvent, so it does not cause various problems, it does not require warm amplifier time, and it requires less energy for fixing.

However, the above-mentioned pressure fixing method has poor fixing properties compared to fixing methods using heat, etc., and is easily peeled off when rubbed.
Since high pressure is required, the fibers of the image forming support, such as copy paper, are destroyed, resulting in weakened paper, and the surface of the copy paper becomes excessively glossy.

In order to solve these drawbacks, research has recently begun on the use of so-called microcapsules as toners for developing electrostatic images. The microcapsule type toner is a powder in which a liquid substance or soft solid exhibiting pressure fixability and a colorant are enclosed as a core material in fine resin capsules.

This microcapsule type toner is capable of enclosing sticky soft solids within the core material.

Compared to conventional pressure fixing toners made of a single resin, this toner is expected to have advantages such as better powder characteristics, fixing at low pressure, and no aggregation or blocking during toner production or storage.

However, conventional microcapsule toners have various drawbacks. For example, JP-A-5
In the publication No. 4-76233.

It has been disclosed that the outer wall of a microcapsule type toner is formed using a polyamide resin, but because the outer wall has low strength, a drying process is necessary to isolate the toner particles and turn them into powder during production. Since it is necessary to carry out spray drying and vigorous agitation must be avoided, it is not possible to obtain a sufficient amount of charge, and therefore the visible image formed tends to have a low image density. . Furthermore, the polymerization reaction of the polymer that forms the capsules of this toner must be carried out at high temperatures, and when magnetic fine powder is included as a magnetic toner, the polymerization reaction of the polymer forming the toner capsule must be carried out at high temperatures. Hydrochloric acid, which is produced in the magnetic material, begins to attack the magnetic material, sacrificing the desired properties.

Further, the same publication describes a microcapsule type toner having an outer wall made of epoxy resin, but it has the disadvantage that the reaction time is long due to the slow reaction rate of the epoxy resin.

Further, JP-A-57-179860 describes a microcapsule type toner having an outer wall made of polyurethane resin or polyurea resin.

This technology has the advantage of fast outer wall formation speed, but
The strength of the wall material is high.

The disadvantage is that the pressure required for fixing is high.

Furthermore, since the outer wall is hard, it has no effect on fixing performance, and merely retains the interior, which actually deteriorates fixing performance. Furthermore, there is a drawback that it is difficult to control the amount of charge. Furthermore, during the polymerization of incyanate and polyamine or polyol, a W10 emulsion in which an organic phase is dispersed in water is unstable and tends to cause aggregation. Furthermore, since a crosslinkable isocyanate is used, crosslinking increases the film strength and rigidity of the outer wall resin, but on the other hand, when used as a toner, the impact strength decreases and the brittleness becomes strong. There is a drawback in that when mechanical force such as stirring or classification of toner particles is applied to the toner particles in the developing device, part of the outer wall tends to be destroyed, resulting in a decrease in fluidity.

[Purpose of the invention]

The purpose of the present invention is to solve all the drawbacks of the above-mentioned prior art, and its first purpose is to provide flexibility to the outer wall,
To provide a microcapsule type toner that not only protects a core material but also has a fixing ability on the outer wall itself.

A second object of the present invention is to provide a microcapsule type toner that does not cause aggregation and is easy to manufacture.

A third object of the present invention is to provide a microcapsule type toner whose charge can be easily controlled.

A fourth object of the present invention is to provide a microcapsule type toner in which the degree of crosslinking of the outer wall resin can be controlled and, as a result, the mechanical strength of the resin can be adjusted to appropriate physical properties.

[Structure of the invention]

The above object of the present invention is to provide a microcapsule type toner having a core material containing a pressure fixing substance and an outer wall for covering the core material, wherein the outer wall is obtained using two or more kinds of incyanates. This was achieved using a microcapsule type toner characterized by containing epoxyurea resin or epoxyurethane resin as a main component.

The present invention will be described in detail below.

The microcapsule type toner of the present invention is composed of an outer wall and a core material. The outer wall has the above structure, and the core material contains a pressure fixing substance and a coloring agent. Note that the coloring agent may be contained in the outer wall instead of the core material, or may be contained in both the core material and the outer wall.

The epoxy urea resin or epoxy urethane resin constituting the outer wall may be a 100% polymer in the outer wall material, or may be a partial polymer instead of a 100% polymer, or may be a partial polymer in the outer wall material. The epoxy resin and the urea or urethane resin may be present in a mixed form.

The above substance can be obtained as follows.

That is, it is obtained by reacting a mixture of two or more isocyanates, which are the raw materials for urea and urethane resins, and an epoxy resin prepolymer or a compound having an epoxy group, which is the raw material for epoxy resins, with a polyvalent amine compound or polyol. . That is, a urea bond is generated by the reaction between an isocyanate and an amine or a polyol, and an epoxy ring is opened by a reaction between an epoxy m-lipid prepolymer or a compound having an epoxy group and an amine. Therefore, it is thought that a substance with the following structure is produced in the outer wall.

10HOH -NH-几'-Nl-1-) (Respectively, 几, 几', R1'' represent a divalent bonding group ψ Furthermore, the form of a mixture of urethane or urea resin and epoxy ring-opening polymer There is a possibility that it exists.

The material obtained as described above constitutes an outer wall and is shaped into a capsule.

One of the two or more isocyanates used in the present invention is a difunctional incyanate, and the others are trifunctional or higher polyfunctional isocyanates.

Examples of the difunctional incyanate include the following.

(1) Hexamethylene diisocyanate 0ON (OH
[ Hiren TMJ (manufactured by Devon) (4) 2.4-Tolylene diisocyanate Commercial product name:
Violet 1-le T' (manufactured by Sumitomo Peyer Cretan) (6-3,3'-dimethyl-diphenyl-4,4'-
Diisocyanate commercial product name: "Hyren H" (manufactured by DuPont) [Suminate B T j (manufactured by Sumima Kagaku Kogyo Co., Ltd.) (6) Diphenylmethane diisocyanate commercial product name 2 [Millione] MTJ (manufactured by Nippon Polyurethane Kogyo Co., Ltd.) r l5onate l 25M J (manufactured by Kasei Upsilon) "Sumidur 44S" (manufactured by Sumitomo Bayer Urethane) (7) 3.3'-dimethyl-diphenylmethane-4
．． 4'-Diincyanate Commercial product name 2 "Hiren D~L" (manufactured by DuPont) (8) Naphthalene diisocyanate OO Commercial product name: [Sumidur 15J (manufactured by Sumitomo Bayer Urethane) (9) Dicyclohexylmethane-diisocyanate Commercial product name: ""DesmoduleW" (Bayer Urethane Co., Ltd. 1 αQ diphenyl ether diisocyanate Commercial product name:
"Suminate E" (manufactured by Ousui Kagaku Shiba Co., Ltd.) Examples of modified bifunctional incyanates other than those mentioned above include "Sumidur 44F-90,""Sumidur3062," [Sumidur PFJ, and "Sumidur." Juul ODJ, [Sumiseal 0632J, Sumidur POJ (manufactured by Sumitomo Bayer Urethane), [Coronet] 2014J.

“Coronate Person P”, “Coronate 2501j.

[Millionate MS-50J, "Coronate 3041"
(manufactured by Nippon Polyurethane Kogyo Co., Ltd.), [Deslanate 2]
4A-900XJ, r Deslanate EXPD-1011
(manufactured by Mukasei Kogyo Co., Ltd.), [Takenate M-402J,
"Takenate F-513", "Takenate I) -10
2J, Takenate L-11504 (manufactured by NiB1 Yakuhin Kogyo Co., Ltd.), etc., and generally any compound having two isocyanate groups can be used.

As the bifunctional incyanate used in the present invention, the above-mentioned ones may be used alone, or two or more may be used in combination.

Examples of trifunctional isocyanates include the following.

(1) Hexamethylene diisocyanate adduct Commercial product name: "Sumidur N" (manufactured by Sumitomo Bayer Urethane) (++)) Reaction product of lylene incyanate and trimethylolpropane Commercial product name: "Sumidur L" (manufactured by Sumitomo Bayer Urethane Co., Ltd.) Commercial product name: "Coronate L" (manufactured by Nippon Polyurethane Industries Co., Ltd.) (ill) ) Liphenylmethane-triisocyanate CO Commercial product name: "Sumidur 几" (manufactured by Sumitomo Bayer Urethane Co., Ltd.) Gy) Reaction product of xamethylene diisocyanate and trimethylolpropane 1 ++ Commercial product name 2 [Coronate] (LJ (manufactured by Nippon Polyurethane Industries) (■) Hexamethylene diisocyanate adduct 11
＼OH2+6NOO Commercial product name: Desmodur El-IJ (manufactured by Sumitomo Bayer Urethane Co., Ltd.) (vD Diphenylmethane diisocyanate cycloaddition product name: r Iaonate L43L J (manufactured by Kasei Upjohn Co., Ltd.) Incyanate hexanoate OO 00N4CJH2+4(3-H 0-(J(-OH2S2NOO) 1 Commercial product name: rT-1004 (Toshisha'R) As a polyfunctional incyanate exceeding trifunctionality, 3For example, the following I can list things.

(n=2.3.4---) (11) Adduct of diphenylmethane diisocyanate and polyvalent polyol (0il)) Adduct of fluorine diisocyanate and polyvalent polyol These do not exist as pure products. However, commercially available products containing difunctionality and polyfunctionality (trifunctionality or more) include the following.

"Sumijoul 44V-10j," Sumijur 44
V-20j, r S B U -l5ocya*1+
e O389J (manufactured by Bayer Urethane) s
"Millione, -to MRJ (manufactured by Nippon Bolikretan Kogyo Co., Ltd.)"
, rPAP1135'', and rPAP20J (manufactured by Kasei Atsubujisen Co., Ltd.).

The trifunctional or higher polyfunctional incyanate may be used alone or in combination of two or more.

The mixing ratio of two or more types of incyanate is such that 1 to 5 polyfunctional incyanates of trifunctionality or more are mixed in the total incyanate.
It is preferable to contain 0 mol%, more preferably 2 to
It is 30 mol%.

Examples of the compound containing an epoxy group include the following, but there are no particular limitations as long as it has two or more epoxy groups in one molecule.

l) Bisphenol A type n = o or integer C Unless otherwise specified, the following is the same ψCommercial products: "Epicoat 80i, rEpicoat 807", "
Epicoat 815J, r Epicoat 819", "Epicoat 827", "Epicoat 828j, r Epicoat 8
34”, “Epicoat 152”, “Epicoat 190”
, “Epicoat YX-310J, [Epicoat DX-2
55, J.

[Epicote 1045-A-70J (manufactured by Yuka Shell Epoxy Co., Ltd.), etc.

2) Resorcinol type 3) Bisphenol F type H 4) Tetrahydroxyphenylmethane type Commercially available products such as Epicote 1031j (manufactured by Yuka Shell Epoxy Co., Ltd.).

5) Novolac type epoxy resin (n = integer of 0 to 4) Commercial products: "Epicoat 152", "Epicoat 154J"
(manufactured by Yuka Shell Epoxy Co., Ltd.) etc.

6) Polyalcohol, polyglycol type epoxy resin (R = H, OH3 group or 0H2CH3 group, etc.) 7) Glycerin triether type commercial product 2 "Epicote 812" (manufactured by Yuka Shell Epoxy Co., Ltd.) etc.

8) Polyolefin type epoxy resin Q representing an aralkyl group 9) Epoxidized soybean oil (m is 0 or an integer) 10) Epoxidized linseed oil 11) Halogenated bisphenol type (X represents at or BrQ Commercial product: "Epicote 1O45-A-70".

[Epicoat 1050J (manufactured by Yuka Shell Epoxy Co., Ltd.) etc.

12) Vinylcyclohexene dioxide 13) Dicyclopentadiene dioxide 14) 3.4-Epoxy-6
-methylcyclohexylmethyl-3,4-epoxy-6
-Methylcyclohexane carbonate 1 The quantitative ratio of the two or more isocyanates of the present invention and the compound containing an epoxy group is 20:80 to 80:20 in terms of isocyanate:compound containing an epoxy group, Preferably the ratio is 30:0 to 60:40.

The polyols or polyamines used in the IMK of the present invention include the following.

l) Voriol Ethylene glycol, propylene glycol.

Diols such as butylene glycol and hexamethylene glycol, glycerin, triols such as trimethylolpropane, trimethylolethane, 1,2.6-hexandriol, pentaerythritol, water, etc. 2) Polyamines ethylene diamine, hexamethylene diamine , diethylenetriamine, iminobispropylamine, phenylenediamine, glycylylenediamine, triethylenetetramine, piperazine, and others.The above-mentioned polyols and polyamines may be used alone or in combination, or in combination with different functional numbers. good.

The mixing ratio of the incyanate and epoxy to the polyol or polyamine is 1:1 to 50%, preferably 1:1.
．． It is 1 to 40 equivalents.

In the present invention, another third resin may be copolymerized or blended with the outer wall containing the epoxy polyurethane resin or the epoxy polyurea resin.

Examples of the third resin include polyamide resin, polyester resin, acrylic resin, styrene resin, and styrene-acrylic resin.

As the core material constituting the microcapsule type toner of the present invention, a pressure fixing material such as a liquid material or a soft solid material containing a colorant is used. Any material may be used as long as it has fluidity or plasticity, and the viscosity is 10 to 1 at a temperature of 60°C.
0,000,000 cps is preferred. Specific examples include liquid polybutene, liquid polychloroprene, liquid polybutadiene, epoxidized soybean oil, and epoxidized triglyceride.

Epoxidized monoester, adipic acid polyester,
Liquid polyester, chlorinated paraffin, trimellitic acid ester, vegetable oils such as soybean oil, silicone oil, mineral oil, polymethyl acrylate, polybutyl acrylate, and polylauryl methacrylate.

Acrylic acid ester oligomers, styrene monomer oligomers, styrene and alkyl acrylate copolymer oligomers, styrene and alkyl methacrylate copolymer oligomers, petroleum residues such as polyvinyl acetate, asphalt, and kiltnide, as well as linoleic acid, linolic acid, Esters of unsaturated fatty acids such as oleic acid, elaidic acid, eleostearic acid, lyrinelaidic acid, gadolenic acid, erucic acid, arachidonic acid, clupanodonic acid, α-lycanic acid, linseed oil, eno oil, tung oil.

Castor oil, hemp demonstration, kapok oil, poppy demonstration, sesame oil,
Vegetable oils that are drying or semi-drying oils such as rice bran oil, safflower oil, soybean oil, corn oil, rapeseed oil, sunflower oil, cottonseed oil, copolymers of acetylene and butadiene, dicyclopentadiene oligomers such as " Examples include synthetic drying oils such as "Finton" (manufactured by Nippon Zeon Co., Ltd.), and others.

A coloring agent is contained in the core material, and in order to obtain a microcapsule type toner suitable as a magnetic toner used as a -component toner, for example.

Fine magnetic powder is contained as part or all of the colorant.

As a coloring agent, carbon black, nigrosine dye (
0,1, fish 50415B), aniline blue (0,1,
Nagi 50405), Calco Oil Blue (0°I, N
azoia Blue 3), chrome ye o
-(0,1,No.

14090), Ultramarine Blue (0,1, 77
103), Debon Oil Red (0・■・N.

26105), quinoline yellow (0,1, 470
05), methylene blue chloride (0,1, Nct5)
2015), Phthalocyanine Blue (0,1,N.

74160), malachite green offsalate (0,
1, fish 42000), lamp black (0, I.

Fish 77266), Rose Bengal (0,1, Nα454
35), mixtures thereof, and others. These colorants need to be contained in a sufficient proportion to form a visible image with sufficient concentration.1 Usually, 1 to 20 parts by weight per 100 parts by weight of the liquid substance, etc. It is considered to be the same.

The magnetic material may be a ferromagnetic metal or alloy such as iron, cobalt, or nickel, including ferrite and magnetite, or a compound containing these elements, or a material that does not contain a ferromagnetic element or is made by subjecting it to appropriate heat treatment. Mention may be made of alloys which exhibit ferromagnetic properties, such as alloys of the type called Heusler alloys containing manganese and copper, such as manganese-copper-aluminum, manganese-copper-tin, or chromium dioxide, among others. These magnetic substances are uniformly dispersed in a liquid substance in the form of fine powder with an average particle size of 0.1-1 μm. And its content is toner 1
20 to 70 parts by weight per 00 parts by weight, preferably 40 to 7 parts by weight
It is 0 parts by weight.

The microcapsule type toner of the present invention can be suitably produced, for example, as follows. That is.

For example, an example of a manufacturing method preferably used in the present invention is as follows.

[0 Two or more of the above incyanates (oil-soluble monomers)
After uniformly mixing the pressure fixing substance and the colorant (if necessary, a curing agent for epoxy resin such as an acid anhydride,
Lewis acids, tertiary amines.

Q.Organic metal salts etc. may be added.Pour this mixture into a dispersion medium such as water containing a suitable dispersion stabilizer,
The mixture is dispersed and suspended by stirring or the like (the processing up to this point is preferably carried out at room temperature or below). Thereafter, the temperature of the yarn is raised (there are two ways to raise the temperature: sudden and gradual).The temperature is maintained at the reaction temperature, and the above-mentioned two or more isocyanates and the epoxy group-reacting amine are added to the water. Alternatively, polyols (water-soluble monomers) are added, allowed to react, and stirring is continued until the reaction is completed.The solids are then separated and dried to produce a microcapsule type toner.

(2) When the pressure-fixable substance is a polymeric substance in the method C1) above, the monomer of the pressure-fixable substance and its polymerization initiator are added, and the monomer is first formed with epoxyurea or epoxyurethane resin. The material may be encapsulated with a pressure-fixable material and then polymerized to form a pressure-fixable material.

(3J When adding two types of water-soluble monomers, they may be added simultaneously or separately.

In methods such as [1] to [2] above, in order to control the particle size of the toner obtained, it is sufficient to control the particle size of the fine particles of the mixture in the reaction system.

For example, this can be achieved by controlling the stirring force while monitoring the particle size and dispersion degree of the fine particles using a microscope.

In order to mix and disperse the colorant into the mixture, a ball mill, attritor, sand grinder, etc. may be used, but the colorant may be treated with a silane coupling agent, a titanium coupling agent, etc. ,
Alternatively, a dispersion improver such as lecithin for dispersing inorganic substances into organic substances may be added.

As a means for dispersing the mixture of the liquid substances and the like in the dispersion medium, a stirring means using mechanical force such as a homomixer, a homogiec, a Waring blender, or an ultrasonic dispersion is used. It is actually necessary to add a dispersion stabilizer to the dispersion medium, thereby maintaining a stable suspension state during the polymerization reaction.

Examples of dispersion stabilizers include water-soluble polymer substances such as gelatin, gelatin derivatives, polyvinyl alcohol, bolistire/sulfonic acid, hydroxymethyl cellulose, hydroxyethyl cellulose, hydroxyglopyl cellulose, sodium carboxymethyl cellulose, and sodium polyacrylate, and anionic substances. Hydrophilic surfactants such as surfactants, nonionic surfactants, cationic surfactants, colloidal silica, alumina, tricalcium phosphate, ferric hydroxide, titanium hydroxide, aluminum hydroxide, etc. Inorganic colloidal substances and others can be effectively used. Of course, two or more of these dispersion stabilizers may be used in combination, and appropriate auxiliary agents may also be used together.

Although the particle size of the microcapsule type 1 toner according to the present invention is not subject to any lateral restrictions, the average particle size is usually 5 to 50 μm, preferably 5 to 30 μm. Further, the particle size of the outer wall and the core material may be the same as in the case of the conventional microcapsule type toner.

When the microcapsule type toner of the present invention contains magnetic fine powder, it can be used alone as a developer,
When the developer does not contain magnetic fine powder, it can be mixed with a carrier to prepare a two-component developer.

The carrier is not particularly limited, but iron powder, glass beads, etc., or resin-coated versions thereof are used, and the toner concentration in the developer consisting of the carrier and toner is 0.
It is 2 to 1Qwt%, preferably 1 to 5wt%. Also, the particle size of the carrier.

The thickness used is 25 to 1000 pm, preferably 30 to 500 pm.

〔Effect of the invention〕

According to the present invention, since two or more types of isocyanates are used, the degree of crosslinking can be freely controlled, and as a result, it was possible to obtain a microcapsule-seeking toner that provides appropriate physical properties such as mechanical strength. In particular, the content of crosslinking components is 2 to 3
When the degree of crosslinking was controlled to be 0 mol%,
It has been found that the toner has extremely good fluidity.

In addition, when developing an electrostatic charge image, frictional electricity is applied due to stirring, and the outer wall of the toner is made of epoxy urea or epoxy urethane resin, which has great durability against friction. Because of this, it will not be crushed even if it is stirred quite vigorously, so it can retain a sufficient amount of charge, and as a result, a visible image with a sufficient 1% of the image density can be formed. ,
The outer wall is made of epoxy urea resin or epoxy urethane resin, and the resin is not affected by moisture, so it retains its fluidity as a powder for a long period of time and does not aggregate. When used as a toner for developing a charge image, a visible image of good quality can be stably formed.

Further, the toner of the present invention is easily torn by a pressure roller with a linear pressure of, for example, 10 to 30 kg/an, although this varies depending on the toughness of its outer wall, particle size, etc.

For example, by constructing the fixing device with such a pressure roller, the toner image made of the toner can be easily fixed onto a supporting paper, for example, a transfer paper. That is, when the capsule is ruptured, the core material sealed inside is released, but since this core material is a pressure-fixable material containing a colorant, it has sufficient visibility and Since pressure is applied to areas that have fluidity or plasticity, the image pressure fixing substance enters or is pushed between the fibers of paper such as transfer paper and is captured, resulting in the toner In the method in which the image is disturbed, inexpensive water can be used as a dispersion medium without any danger, and the resulting particles are essentially spherical, which is one of the important physical properties in electrophotography. It is possible to reliably produce a toner with high fluidity.

〔Example〕

Examples of the present invention will be described below, but the embodiments of the present invention are not limited to these. In addition"
"Parts" means parts by weight unless otherwise specified.

Toner No. of the present invention, l-N113 and comparative toner N
The materials used in the preparation of α1 were mixed and stirred for about 1 hour using a sand grinder to uniformly mix and disperse the mixture to obtain a magnetic ink.

Separately, add 14 g of colloidal tricalcium phosphate prepared with tristrium phosphate and calcium chloride, and 0.06 g of sodium dotesylbenzenesulfonate to 800 mff of water.
Prepare a dispersion liquid in which 1 is uniformly dispersed.

Next, the magnetic ink was added to this dispersion.

Using a homo jetter (manufactured by Tokushu Kika Kogyo Co., Ltd.), the number of revolutions is 8.
Approximately 5-2 000-9000 rpm under optical microscope observation
The mixture was dispersed for about 10 minutes to form fine oil droplets with a diameter of 0 μm.

Next, the dispersion was transferred to a four-bottle flask with a diameter of 2ρ, and under low-speed stirring, an aqueous solution containing υ) was dissolved at room temperature for about 15
Added over a period of minutes. The mixture was stirred at room temperature for 15 minutes, and then the temperature was gradually raised to react at 80° C. for 7 hours to obtain microcapsules having the polymer (5) as a core material and an epoxy polymer and a urethane polymer as an outer wall.

Next, this was cooled and 40-0 concentrated hydrochloric acid was added.

Tricalcium phosphate, which is a dispersion stabilizer, is decomposed and removed, and PI3. The microcapsule type toner of the present invention was obtained by washing with water and drying.

In the above, , ), L'l, and ■ are respectively expressed as ~l
A toner of the present invention with Nα1-No.3 was obtained using the substance shown in FIG.

Comparative toner fish 1 was also obtained in the same manner as above without using only (0).

Experimental Example Fluidity Evaluation Fluidity was measured for each of the present invention toners 1 to 3 and comparative toner Storm 1 obtained as described above. The evaluation method was based on the quietness density described below.

This method is one of the evaluation methods for fluidity, and is a simple method for evaluating fluidity in systems where there is no large difference in density, such as heathered yarn, and the larger the value, the better the fluidity. be.

(Measurement method) To simplify the method used in an actual check room, a cone-shaped funnel was placed on top of a 20-mesh graduated cylinder, and the microcapsule-type toner was gently dropped through a 100-mesh sieve from above, resulting in 20 ml of toner! The weight was measured and the quietness density was calculated.

(Measurement Results) The results are shown in Table 1, and it can be seen that the toner of the present invention has good fluidity.

The aggregation status was visually observed and evaluated. The evaluation results are based on a three-level system: ○... Not at all. △... A little bit.

×・・・・・・There is a kana page. ” as shown in Table ■.

The measurement was performed by mixing 20 parts of iron powder carrier with 1 part of the toner of the present invention and measuring by the pull-off method.

The charge amount values are as shown in Table 1.

Evaluation of Fixability Next, using each of the above-mentioned toners as a developer, an electrophotographic copying machine ru-Eix-1200J (manufactured by Konishi Roku Photo Industries Co., Ltd.) was subjected to pressure fixing m (pressure fixing machine 20 kg /
An electrostatic charge image was developed and the toner image was transferred to a fusing member made of plain paper.

The fixability of the transferred image was evaluated. The results are shown in Table-1. In addition, the evaluation of fixability is U-Bix55k.
The Koyoshi test using g-vapor and the tape using Sellotape were evaluated using a $1 grain tester.

In the table, ◯ indicates good and × indicates poor.

Margin below

Claims (1)

[Claims] A microcapsule type toner having a core material containing a pressure fixing substance and an outer wall for covering the core material,
A microcapsule type toner characterized in that the outer wall contains as a main component an epoxyurea resin or an epoxyurethane resin obtained using two or more types of isocyanates.