JPH04142554A - Capsule toner - Google Patents

Abstract

PURPOSE:To obtain excellent fixability without deteriorating the quality of a photosensitive body by using an aliphat. satd. hydrocarbon solvent as a high boiling solvent and forming a core material by using a polymer which dissolves therein. CONSTITUTION:The ore material contains at least the high boiling solvent and the polymer. The high boiling solvent is the aliphat. satd. hydrocarbon solvent. The polymer dissolved in the aliphat. satd. hydrocarbon solvent is used. The aliphat. satd. hydrocarbon solvent is aliphat. satd. hydrocarbon having >=140 deg.C b. p. or liquid essentially consisting of this aliphat. satd. hydrocarbon. The polymer is preferably a high-polymer compd. contg. the vinyl monomer expressed by formulas as its monomer component and may be the homopolymer of the vinyl monomer or a copolymer with other monomers; for example, the polymer includes a lauryl methacrylate/styrene copolymer.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a capsule toner for electrophotography.

[Conventional technology]

Conventionally, microcapsule toner formed from a core material and an outer shell has been known as an electrophotographic toner for developing electrostatic images formed on the surfaces of electrophotographic photoreceptors, electrostatic recording materials, etc. Various proposals have been made. For example, JP-A-58-145964 and JP-A-400-8395
No. 8 discloses a capsule toner containing at least a high boiling point solvent and a polymer in the core material. Also,
JP-A-63-163373 and JP-A No. 51-132831
Publication No. 1 discloses a capsule toner using a specific chlorinated paraffin as a high boiling point solvent in the core material.

[Problem to be solved by the invention]

However, JP-A-58-145964 and JP-A-80-
The high boiling point solvent disclosed in JP 83958 and the like is a so-called plasticizer, and has a large dissolving power for resin.
When an organic photoreceptor is used as a photoreceptor, the surface of the photoreceptor may be damaged by the high boiling point solvent present in the capsule toner, and the high boiling point solvent may ooze out from the capsule with a thin outer shell or evaporate. It has been found that there is a drawback that the photoreceptor changes in quality due to the boiling point solvent. In addition, chlorinated paraffin, which is a high boiling point solvent described in JP-A-63-1.63373, has essentially a dissolving power for general-purpose resins such as acrylic resins, polycarbonate resins, and polyester resins. It has the disadvantage of altering the quality of the organic photoreceptor. Also, JP-A-51-132838
The publication discloses an example containing an aliphatic saturated hydrocarbon and a polymer as the core material, or in the second case, the polymer is contained in a dispersed state in the aliphatic hydrocarbon.

Further, in other examples, a core material in which a polymer is dissolved using an aromatic hydrocarbon such as toluene is exemplified. However, when the polymer is used in a dispersed state, the polymer does not penetrate or adhere to the adherend sufficiently, and
As a result, satisfactory fixing performance cannot be obtained.

Furthermore, when an aromatic hydrocarbon material such as toluene is used, it has the disadvantage of altering the quality of the organic photoreceptor.

The present invention has been made in view of the above-mentioned conventional problems.

An object of the present invention is to provide a microcapsule toner that does not alter the quality of an organic photoreceptor and has excellent fixing properties.

[Means to solve the problem]

The present invention provides a capsule toner comprising a core material and an outer shell covering the core material, wherein the core material contains at least a high boiling point solvent and a polymer, and the high boiling point solvent is an aliphatic saturated hydrocarbon solvent. It is characterized in that the polymer is dissolved in the aliphatic saturated hydrocarbon solvent.

The present invention will be explained in detail below.

In the present invention, the high boiling point solvent, which is one of the constituent components of the core substance, is an aliphatic saturated hydrocarbon solvent. The aliphatic saturated hydrocarbon solvent in the present invention has a boiling point of 140°C.
The above preferably means an aliphatic saturated hydrocarbon having a temperature of 160° C. or higher or a liquid containing an aliphatic saturated hydrocarbon as a main component. Specific examples of aliphatic saturated hydrocarbon solvents suitable for use in the present invention include l5opa, manufactured by Exxon Chemical Co., Ltd.
r HSIsoparL, 1soparM, l5op
ar HSEXXSOL D40, EXXSOLD80
, EXXSOL DIIO can be listed.

The polymer, which is another component of the core material, is a polymer compound that dissolves in the aliphatic saturated hydrocarbon solvent,
Preferably, it is a polymer compound containing a vinyl monomer represented by the following general formula as a monomer component.

(In the formula, R represents a hydrogen atom or a methyl group, and n represents an integer from 7 to 17.) The above-mentioned polymer compound used in the present invention is a homopolymer of vinyl monomers represented by the above-mentioned general formula. It may be present, or it may be a copolymer with other monomers. A preferred example of the copolymer is a lauryl methacrylate-styrene copolymer.

Further, in the present invention, it is preferable that the core material polymer contains a petroleum resin or a rosin resin in addition to the above-mentioned polymer compound. This is particularly effective when the above polymer alone has fluidity, and can improve fixing speed and fixing strength.

Petroleum resins include aliphatic resins, aromatic resins, copolymer resins, aliphatic hydrogenated petroleum resins, alkyl phenol resins, and chroman indene resins. Among these, aromatic petroleum resins are particularly preferred since they have excellent compatibility with the polymer compound. Examples of the rosin resin include rosin, modified rosin, glycerin ester of the rosin, and pentaerythritol ester of the rosin.

These petroleum resins and rosin resins account for 1% of all polymers.
% to 80%, preferably 5% to 50% (wt).

In the core material of the present invention, for the purpose of preventing offset,
In addition to the above-mentioned polymer compound and petroleum resin, wax may also be included as a component of the core material. Also,
Silicone oil can also be included as a component of the core material. Examples of the wax include natural waxes such as paraffin wax, microlistalline wax, montan wax, carnauba wax, candelilla wax, beeswax, and synthetic waxes such as polyethylene wax, modified wax, cetyl alcohol, and stearic acid.

Furthermore, a coloring agent can also be included.

Coloring materials include carbon black, red iron, dark blue,
Inorganic pigments such as titanium oxide, azo pigments such as Fast Yellow, Disazo Yellow, Pyrazolonelet, Killet Red, Brilliant Carmine, and Rose Brown, phthalocyanine pigments such as copper phthalocyanine, metal-free phthalocyanine,
Examples include fused polycyclic pigments such as flavanthrone yellow, dibromoanthrone orange, perylene red, quinacrylon red, and dioxazine violet.

Further, disperse dyes, oil-soluble dyes, etc. can also be used.

Furthermore, as a magnetic one-component toner, all or part of the black colorant can be replaced with magnetic powder. As the magnetic powder, magnetite, ferrite, a single metal such as cobalt, iron, or nickel, or an alloy thereof can be used.

The outer shell of the capsule toner of the present invention includes polyurea resin, polyurethane resin, polyamide resin, polyester resin,
Epoxy resins, epoxy urea resins, and epoxy urethane resins are preferred, and among these, polyurea resins or polyurethane resins alone, or a mixture of both, or epoxy urea resins or epoxy urethane resins alone, or mixtures of both are preferred. It is more preferable.

There are no particular restrictions on the encapsulation method, but in consideration of the completeness of the coating and the mechanical strength of the outer shell, a carcelization method using interfacial polymerization is superior. A known method can be used to manufacture the capsule toner by interfacial polymerization. (
For example, JP-A-57-179860, JP-A No. 58-6894
No. 8, No. 59-148066 and No. 59-1625
(No. 62) The thickness of the outer shell is desirably different depending on whether the purpose is pressure fixing or heat fixing, and the types or composition ratios of the constituent components may also be changed. As the core material, if the purpose is pressure fixing, a core material mainly consisting of a component having pressure fixing properties is used, and if the purpose is heat fixing, a core material mainly consisting of a component having heat fixing properties is used. Substances are used. The polymer compound is added to 1 in the core material.
The method of incorporating the component into the capsule is to make it into a polymer state in advance, add it together with other core material components, a low boiling point solvent, and an outer shell forming component, and then simultaneously form the outer shell through interfacial polymerization, or at the same time as the outer shell is formed. Later, a method can be used in which the low boiling point solvent is forced out of the system to form a core material.

Further, the particle size of the capsule toner of the present invention is preferably in the range of 5 to 25 in terms of volume average particle size.

〔Example〕

Example 1 (Preparation of capsule particles) Polylauryl methacrylate (MW-5XIO') 5
0g and 15g of petroleum resin (FTREfL25: manufactured by Mitsui Petrochemicals) were treated with an aliphatic saturated hydrocarbon solvent (Isop).
25g (manufactured by Exxon Chemical Co., Ltd.), 30g of ethyl acetate
It was dissolved in a mixture of g. Add magnetic powder (EPT) to this solution.
-1000, manufactured by Toda Kogyo Co., Ltd.) was added thereto, and the mixture was subjected to a dispersion treatment for 20 hours in a ball mill. Next, to 100 g of this dispersion, 15 g of isonanate (Sumidur L, manufactured by Sumitomo Bayer Urethane) and 15 g of ethyl acetate were added.
The mixture was thoroughly mixed (this liquid is referred to as liquid A).

On the other hand, add 200 g of ion-exchanged water to 150 g of human quinpropyl methylcellulose (Metrose 65: manufactured by Shin-Etsu Chemical Co., Ltd.)
10g was dissolved and cooled to 5°C (this liquid is referred to as liquid B). Emulsifying machine (autohomogen mixer: manufactured by Shukikaku Co., Ltd.)
The B solution was stirred, and the A solution was slowly added thereto to effect emulsification. In this way, an O/W emulsion in which the average particle size of oil droplets in the emulsion was about 12 knots was obtained.

Next, instead of the emulsifier, a stirrer equipped with propeller-type stirring blades (Three-One Motor: manufactured by Shinto Kagaku Co., Ltd.) was used.
Stirring was carried out at 400 rpm. After 10 minutes, a 5% aqueous solution of diethylenetriamine LO[Ig was added dropwise thereto.

After the dropwise addition was completed, the mixture was poured into 2 liters of ion-exchanged water, thoroughly stirred, and allowed to stand still. After the capsule particles had settled, the supernatant was removed. This operation was repeated seven more times to wash the capsule particles. In this way, capsule particles of the present invention were obtained. Ion-exchanged water was added to the capsule particles to prepare a suspension with a solid content concentration of 4,096.

(Tonerization of capsule particles) Suspension 125 of capsule particles prepared as described above
g (equivalent to 50 g of capsule particles) was added with 125 g of ion-exchanged water and stirred at 200 revolutions using a stirrer equipped with a propeller-type stirring blade (Three-One Motor: manufactured by Shinto Kagaku Co., Ltd.). After adding 5 g of IN nitric acid and 4 g of a 10% aqueous cerium sulfate solution, 0.5 g of ethylene glycol dimethacrylate was added thereto, and the mixture was reacted at 15° C. for 3 hours. After the reaction was completed, the mixture was poured into 1 g of ion-exchanged water, thoroughly stirred, and allowed to stand still. After the capsule particles had settled, the supernatant was removed. This operation was repeated two more times to wash the capsule particles.

In this way, capsule particles in which ethylene glycol dimethacrylate was graft-polymerized on the surface of the capsule shell were obtained.

This was resuspended in ion-exchanged water again, and a stirrer equipped with propeller-type stirring blades (Three-One Motor, manufactured by Shinto Kagaku Co., Ltd.) was used.
The mixture was stirred at 200 rpm. Next, 0.4 g of potassium persulfate, trifluoroethyl methacrylate LK, and 016 g of sodium bisulfite were added in this order, and the reaction was carried out at 25° C. for 3 hours. After the reaction was completed, the mixture was poured into 2 g of ion-exchanged water, thoroughly stirred, and left to stand still. After the capsule particles had settled, the supernatant was removed. This operation was repeated four more times to wash the capsule particles. In this way, a capsule toner in which trifluoromethyl methacrylate was graft-polymerized on the surface of the capsule shell was obtained.

The obtained capsule suspension was poured into a stainless steel vat and dried in a dryer at 60° C. for 10 hours. 3 g of the obtained capsule toner and 100 g of iron powder carrier whose surface was coated with phenol resin were mixed in an environment with a temperature of 20° C. and a humidity of 50%. When the charge amount of the capsule toner was measured by a blow-off method, it was -16 μC/g. Similarly, when mixed in an environment with a temperature of 28°C and a humidity of 80%, the charge amount of the capsule toner was measured using the blow-off method.
It was 4μC/g.

Next, hydrophobic silica (R972) was added to 100 parts of this toner.
, manufactured by Nippon Aerosil Co., Ltd.) was added and thoroughly mixed, and image quality was evaluated under an environment of a temperature of 20° C. and a humidity of 50%. The copying machine used was a Fuji Xerox PX2700 equipped with an organic photoreceptor modified to use capsule toner, and copy samples were obtained by reverse development. As a result, no deterioration was observed on the photoreceptor until the 5000th copy, and stable copies with no image quality defects were obtained.

Comparative Example 1 A capsule toner containing dioctyl adipate as a high boiling point solvent was obtained by carrying out the same process as in Example 1 except that the aliphatic saturated hydrocarbon solvent was replaced with dioctyl adipate. 3 g of the obtained capsule toner and 100 g of iron powder carrier whose surface was coated with phenol resin were heated at a temperature of 2.
The mixture was mixed in an environment of 0° C. and 50% humidity. The amount of charge was measured by the blow-off method and was found to be -14 μC/g. Next (hydrophobic silica (R9) for 100 parts of toner here)
72 (manufactured by Nippon Aerosil Co., Ltd.) was added and thoroughly mixed, image quality was evaluated in the same manner as in Example 2 under an environment of a temperature of 20° C. and a humidity of 50%. When the 3000th sheet is completed,
When the surface of the photoreceptor was closely observed, it was observed that fine cracks had occurred. If you exceed 3500 sheets,
Fine black lines corresponding to the cracks appeared on the copy, resulting in image quality defects.

Example 2 A capsule toner of the present invention was obtained by carrying out the same process as in Example 1, except that the petroleum resin was replaced with a rosin resin (ester gum tlP, manufactured by Arayo Kagaku Co., Ltd.).

3 g of the obtained capsule toner and 100 g of iron powder carrier whose surface was coated with phenol resin were heated at a temperature of 20°C and a humidity of 5.
Mixed in a 0% environment. When the amount of charge was measured by the blow-all method, it was -15 μC/g. Next, 1 part of hydrophobic silica (R972, manufactured by Nippon Aerosil Co., Ltd.) was added to 100 parts of this toner, mixed thoroughly, and then heated to 20°C.
When image quality was evaluated in the same manner as in Example 2 under an environment of 50% humidity, no deterioration was observed on the photoreceptor until the 5000th copy, and stable copies without image quality defects were obtained.

Example 3 (Preparation of capsule particles) Polystearyl methacrylate (Mw"5X10')
50 g of l5opar L and 30 g of ethyl acetate were added to 20 g of petroleum resin (FTR6070: manufactured by Mitsui Petrochemicals) and dissolved therein. Add 5g of red pigment (Hosta Balm Scarlet GO, manufactured by Bayer) here,
The mixture was dispersed in a ball mill for 20 hours. Next, this dispersion 10
10 g of Epotote YD-8125 (manufactured by Tobu Kasei Co., Ltd.) and 5 g of toluylene diisocyanate (manufactured by Coronate Tony Nippon Polyurethane Co., Ltd.) were added and mixed to 0 g (this liquid is referred to as liquid A). On the other hand, hydroxypropyl methylcellulose (Metrose 65) was added to ion exchange water 2502.
)150: manufactured by Shin-Etsu Chemical Co., Ltd.) 10g was dissolved and cooled to 5°C (this liquid is referred to as liquid B). Solution B was stirred using an emulsifier (auto homo mixer, manufactured by Shukki Kako Co., Ltd.), and solution A was slowly added thereto to perform emulsification. In this way, an O/W emulsion with an average particle size of about 12 particles of Uradori in the emulsion was obtained. Next, instead of the emulsifier, a stirrer equipped with propeller-type stirring blades (Three-One Motor: manufactured by Shinraikagakusha Co., Ltd.) was used, and the mixture was stirred at 4 (] (1 rotation/minute).

After 10 minutes, 100 g of a 2.5% diethylenetriamine aqueous solution was added dropwise thereto. After the dropwise addition was completed, stirring was continued to carry out the capsule reaction for 3 hours. After the reaction was completed, the mixture was poured into 2 g of ion-exchanged water and thoroughly stirred, followed by centrifugation and the supernatant liquid was removed. This operation was repeated five more times for washing. In this way, red capsule particles of the present invention were obtained. Ion-exchanged water was added to the capsule particles to prepare a suspension with a solid content concentration of 40%.

(Tonerization of capsule particles) 125 g of the suspension of capsule particles prepared as above
(equivalent to 50 g of capsule particles) and 12 ml of ion-exchanged water.
Add 5 g and use a stirrer equipped with a propeller-type stirring blade (
Three-one motor: 200 revolutions/manufactured by Shinraikagakusha
Stir for 1 minute. After adding 5 g of IN sulfuric acid and 4 g of a 10% aqueous cerium sulfate solution, 0.5 g of ethylene glycol dimethacrylate was added thereto, and the mixture was reacted at 15° C. for 3 hours. After the reaction was completed, the mixture was poured into 1 fl ion-exchanged water, thoroughly stirred, and allowed to stand still. After the capsule particles had settled, the supernatant was removed. This operation was repeated two more times to wash the capsule particles. In this way, capsule particles in which ethylene glycol dimethacrylate was graft-polymerized on the surface of the capsule shell were obtained. This was resuspended in ion-exchanged water and stirred at 200 rpm using a stirrer equipped with propeller-type stirring blades (Three-One Motor: manufactured by Shinraikagakusha). Next, 0.4 g of potassium persulfate, a mixed solution of 1.5 g of trifluoroethyl methacrylate and 1 g of vinyl acetic acid, and 0.18 g of sodium bisulfite were sequentially added to this.
The reaction was carried out at 25°C for 3 hours. After the reaction was completed, the mixture was poured into 2 g of ion-exchanged water, thoroughly stirred, and allowed to stand still. After the capsule particles had settled, the supernatant was removed. This operation was repeated four more times to wash the capsule particles. In this way, a capsule toner in which trifluoroethyl methacrylate was graft-polymerized on the surface of the capsule shell was obtained.

Pour the obtained capsule suspension into a stainless steel hat,
It was dried in a dryer at 60°C for 10 hours. 3 g of the obtained capsule toner and 100 g of iron powder carrier whose surface was coated with phenol resin were mixed in an environment with a temperature of 20° C. and a humidity of 50%. When the charge amount of the capsule toner was measured by the blow-off method, it was -2 .mu.c/g. Next, 1 part of hydrophobic silica (R972: manufactured by Nippon Aerosil Co., Ltd.) was added to 100 parts of this toner, and after thorough mixing, the image quality was evaluated in the same environment as in Example 2 at a temperature of 20°C and a humidity of 50%. I did it. As a result, no deterioration was observed on the photoreceptor until the 5000th copy, and stable copies with no image quality defects were obtained.

〔Effect of the invention〕

As mentioned above, the capsule toner of the present invention uses an aliphatic saturated hydrocarbon solvent as a high boiling point solvent and forms a core substance using a polymer dissolved in the solvent. When the developer is used on an organic photoreceptor, it does not damage or change the quality of the photoreceptor.

Procedural amendment (spontaneous) January 13, 1990 Director General of the Patent Office Toshi Uematsu 1゜2゜3゜4゜Indication of case 1990 Patent Application No. 265171, title of invention Capsule Toner Supplement 1E Case Relationship Patent applicant address 3-3-5 Akasaka, Minato-ku, Tokyo Name (
549) Fuji Xerox Co., Ltd. Representative Yotabe Kobayashi

Claims (5)

[Claims] (1) In a capsule toner consisting of a core material and an outer shell covering the core material, the core material contains at least a high boiling point solvent and a polymer, and the high boiling point solvent is an aliphatic saturated hydrocarbon solvent. , a capsule toner characterized in that the polymer is dissolved in the aliphatic saturated hydrocarbon solvent. (2) The capsule toner according to claim 1, wherein the core material polymer is a polymer compound containing a vinyl monomer represented by the following general formula as a monomer component. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, R represents a hydrogen atom or a methyl group, and n represents an integer from 7 to 17.) (3) The capsule toner according to claim 1, wherein the core material polymer further contains a petroleum resin. (4) The capsule toner according to claim 1, wherein the core material polymer further contains a rosin resin. (5) The capsule toner according to claim 1, wherein the outer shell is made of a polyurea resin and/or a polyurethane resin, or an epoxyurea resin and/or an epoxyurethane resin.