JP2675041B2 - Developer - Google Patents

Description

TECHNICAL FIELD The present invention relates to a developer, and more particularly to a developer in which deterioration of characteristics of the developer is prevented.

(Prior Art and its Problems) As a developing method applied to an electrophotographic method or an electrostatic recording method, a toner is triboelectrically charged to give an electric charge, and this toner forms an electrostatic latent image on a photoconductor or an electrostatic recording material. A method of visualizing is known. The toner electrostatically adhered to the photoconductor or the electrostatic recording medium is transferred to a transfer paper and then fixed to form a copy. Ideally, it is desirable that the transfer of the toner to the transfer paper is completed completely, but the toner that could not be transferred actually remains on the photoconductor or the electrostatic recording material. This residual toner is cleaned by various methods.

In the cleaning of the residual toner, the toner that cannot be removed is gradually accumulated on the surface of the photoconductor or the like thousands of times or tens of thousands of times during the copying process, and so-called cleaning failure or toner filming occurs.

In order to improve such a phenomenon, for example, Japanese Patent Publication No. 48-
Japanese Patent No. 8141 discloses a method of adding an organic polymer having a low surface energy such as polytetrafluoroethylene or polyvinylidene fluoride to toner powder. In addition,
In JP-A-52-84741 and JP-A-60-186851, polystyrene particles or acrylic resin particles are added to a developer to prevent cleaning failure or toner filming due to a decrease in adhesion or a polishing effect. .

These methods are useful to some extent in terms of preventing cleaning failure or toner filming, but the triboelectric chargeability of the toner is lowered as compared with the case where the developer containing such an additive is not mixed, Especially, it appears remarkably under high temperature and high humidity. Therefore, the image density is lowered and the fog is increased. This is based on the above-mentioned JP-A-52-1
Even the methods such as 84741 and JP-A-60-186851 are not sufficiently satisfactory.

(Means for Solving the Problems) The inventors of the present invention provide a developer capable of preventing the cleaning failure or the toner filming without lowering the triboelectric chargeability of the toner. That is, according to the present invention, in a developer containing toner powder and polymer fine powder having an average particle size smaller than the toner powder, the constituent components of the polymer fine particles are (1) a zwitterionic group and (2) an amino group, There is provided a developer having a group selected from the group consisting of a group containing a silicon atom, an acid group and a halogen element.

In the present invention, the toner powder has an average particle size smaller than that of the toner powder, and its constituent components are (1) a zwitterionic group and (2) an amino group, a group containing a silicon atom, an acid group and a halogen element. There is provided a method for controlling charging characteristics of a toner, which comprises adding a polymer fine powder having a group selected from the group consisting of 0.01 to 10% by weight based on the amount of the toner powder.

As the polymer fine powder used in the present invention, those polymerized by various polymerization methods such as emulsion polymerization, soap-free emulsion polymerization, suspension polymerization and non-aqueous dispersion polymerization can be used. Also,
It is possible to use a fine powder obtained by dissolving the polymer obtained by each of the above-mentioned polymerization methods, solution polymerization, bulk polymerization, etc. in a solvent and then granulating by a spray drying method.

However, fine particles obtained by emulsion polymerization or seed emulsion polymerization are preferably used. In particular, it is preferable that the particles have almost the same size, that the electric characteristics of the surface of the particles are substantially uniform, and that the triboelectrification capacity and the charging resistance value are uniform and that the particles have a nearly spherical shape.

The molecular weight of the polymer used for the fine powder according to the present invention is not particularly limited, and a polymer having any molecular weight can be used within a range not departing from the object of the present invention, and it may be crosslinked in some cases. It does not matter even if it is an ultra high molecular weight polymer.

The glass transition temperature of the polymer used in the fine powder according to the present invention is preferably room temperature or higher, but a polymer having a glass transition temperature of room temperature or lower is used within the allowable range of the fluidity and blocking property of the toner. You can

The zwitterionic group present in the constituent components of the polymer fine powder of the present invention is [Wherein A represents a C _{1 to} C ₆ linear or branched alkylene group, a phenylene group or a substituted phenylene group], and is an amino (sulfonic) acid-type zwitterionic group or a sulfobetaine-type zwitterionic group. is there. The introduction of amino (sulfonic acid) type zwitterionic groups can be carried out by the formula as described in JP-A-57-139111. [In the formula, R ₁ is a substituent containing a radically polymerizable ethylenically unsaturated group, and R ₂ is H or a carbon atom of C _{1 to} C ₃₀ which may contain various substituents. It is a hydrogen-based substituent, R ₃ is a C ₁ -C ₆ hydrocarbon-based substituent, and B is a —COOH group or a —SO ₃ H group. ]
You may use at least 1 sort (s) chosen from the polymeric amino acid compound shown by as a polymeric monomer. As the polymerizable amino acid compound, a monomer (for example, N- (vinylbenzyl) taurine, N-methyl-N- (vinyl) which can be produced by an addition reaction of a benzyl halide and an aminosulfonic acid compound having a primary or secondary amino group is used. Benzyl) taurine, N- (isopropenylbenzyl) taurine, etc.); A monomer (eg, N- (2-hydroxy-3-) which can be produced by reacting an oxirane compound with an amino acid compound having a primary or secondary amino group. Aryloxypropyl) taurine, 2- [N- (2-hydroxy-3-allyloxypropyl)] taurine, N- (2
-Hydroxy-3-allyloxypropyl) alanine and the like).

formula: [In the formula, A represents a C _{1 to} C ₆ linear or branched alkylene group, a phenylene group, or a substituted phenylene group. ] The aminosulfonic acid type zwitterionic group represented by the formula (1) is a polymer compound containing such a group (see, for example, JP-A-55-6054).
No. 8 discloses a polyester resin, JP-A No. 57-40522 discloses an epoxy resin, and JP-A No. 54-24357 discloses an acrylic resin) as a dispersion stabilizer or an emulsion stabilizer. Good.

A polyester resin containing an aminosulfonic acid type zwitterionic group has the formula: [Wherein R ₄ has at least one hydroxyl group,
C _{1 which} may contain —O— or —COO— in the molecular group
To C ₂₀ alkyl group, R ₅ is hydrogen atom, C _{1 to} C ₂₀ alkyl group, alkyl group or cyclic group having at least one hydroxyl group and / or sulfonic acid group, and A is
It represents a C _{1 to} C ₆ linear or branched alkylene group, a phenylene group or a substituted phenylene group. ] The hydroxyl group-containing aminosulfonic acid type zwitterionic compound represented by the above is used in an amount of 0.05 to 50% by weight based on all reaction components, and a polybasic acid compound and, if necessary, a polyhydric alcohol and / or an oxirane compound. It is obtained by reacting. Examples of the hydroxyl group-containing aminosulfonic acid type zwitterionic compound include hydroxyethyl taurine, dihydroxyethyl taurine, dihydroxypropyl taurine and the like.

An epoxy resin containing an aminosulfonic acid type zwitterionic group has the formula: [In the formula, R ₆ and R ₇ represent hydrogen or a methyl group. Epoxy resin having terminal groups represented by, the formula: in _{R 8 -NH-R 9 -SO 3} M [ wherein, R ₈ is an alkyl group or substituted alkyl group of which a hydrogen or a C ₁ ~C _20, R ₉ is C ₁ -C ₆ alkylene or substituted alkylene group, M represents amine, alkali metal or ammonia. ] The amino sulfonate of [] is reacted, and then the reaction product is treated with an acid.

Formula: Examples of the amino acid salt of _{R 8 -NH-R 9 -SO 3} M is taurine, 2-amino-propanesulfonic acid, 3-amino butane sulfonic acid, 1-amino-2-methylpropanesulfonic acid, N-
Included are alkali metal salts such as ethyl taurine, amine salts and ammonium salts.

Acrylic resins containing aminosulphonic acid type zwitterionic groups have the formula: [In the formula, R ₁ is a substituent containing a radically polymerizable ethylenically unsaturated group, and R ₂ is H or a carbon atom of C _{1 to} C ₃₀ which may contain various substituents. It is a hydrogen-based substituent, R ₃ is a C ₁ -C ₆ hydrocarbon-based substituent, and B is a —COOH group or a —SO ₃ H group. ] It is obtained by polymerizing or copolymerizing at least one monomer selected from the polymerizable amino acid compounds represented by

Sulfobetaine-type zwitterionic groups are described, for example, in JP-A-53-
Formula as disclosed in 72090: [Wherein R ₁₀ is a hydrogen atom or a methyl group, R ₁₁ and R ₁₂
Are the same or different and are C _{1 to} C ₆ alkyl groups, A ₂ is O or NH, and m ₁ and n ₁ are the same or different and represent an integer of 1 to 12. ] Or a compound represented by the formula: [In the formula, R ₁₃ is a hydrogen atom or a methyl group, R ₁₄ is a hydrogen atom or a C _{1 to} C ₃ alkyl group, m ₂ is an integer of 0 to 6 and n ₂
Represents an integer of 1 to 6, and A ₂ has the same meaning as above. ] It is introduced by a method of using a resin obtained by polymerizing or copolymerizing the compound represented by: as a dispersion stabilizer or a surfactant, or a method of copolymerizing these compounds as other polymerizable monomers with other polymerizable monomers. You can

Examples of the compound represented by the above formula include N, N-dimethyl-N-methacryloxyethyl-N- (3-sulfopropyl) -ammonium betaine, N, N-dimethyl-
Examples thereof include N-methacrylamidopropyl-N- (3-sulfopropyl) -ammonium betaine and 1- (3-sulfopropyl) -2-vinylpyridinium betaine.

The polymer fine powder of the present invention, in addition to the above-mentioned zwitterionic group,
It has a group selected from the group consisting of an amino group, a group containing a silicon atom, an acid group and a halogen element. The method of introducing each group will be described.

The introduction of the amino group copolymerizes the amino group-containing polymerizable monomer during the synthesis of the polymer fine powder. Examples of the amino group-containing polymerizable monomer include N, N-dimethylaminomethyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate and the like. , N-dialkylaminoalkyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylamide, N, N-dialkylaminoalkyl (meth) acrylamide such as N, N-dimethylaminopropyl (meth) acrylamide . Further, the amino group may be introduced by using an amino group-containing polyester or an amino group-containing acryl as a dispersion stabilizer or a surfactant during the synthesis of the polymer fine powder. Amino group-containing polyesters are prepared by a known polyester synthesis reaction using alkanolamines such as ethanolamine, diethanolamine and triethanolamine as one of the components, and amino group-containing acrylics are prepared by using the above amino group-containing polymerizable monomers. It is produced by polymerization or copolymerization.

For the introduction of silicon atoms, during the synthesis of the polymer fine powder, a silicon atom-containing polymerizable monomer is copolymerized, or a silicon atom-containing acrylic resin obtained by copolymerizing this is used as a dispersion stabilizer or a surfactant. The polymerizable monomer containing a silicon atom has the general formula: [In the formula, R ₁₅ is H or CH ₃ , R ₁₆ is an alkylene group, R ₁₇ is an alkyl group or a phenyl group, and n is an integer of 1 to 5. ] Is mentioned. As a concrete example, Is mentioned.

The introduction of the acid group is carried out by copolymerizing an acid group-containing polymerizable monomer such as a carboxyl group, a sulfonic acid group and a phosphoric acid group during the synthesis of the polymer fine powder.

Examples of the carboxyl group-containing monomer include acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid, fumaric acid, monobutyl itaconate, monobutyl maleate and the like. Examples of the phosphoric acid group-containing monomer include acid phosphooxyethyl methacrylate, acid phosphooxypropyl methacrylate, 3-chloro-2-acid phosphooxypropyl methacrylate and the like.

Furthermore, examples of the sulfonic acid group-containing monomer include 2-
Acrylamide-2-methylpropanesulfonic acid, 2-
Examples thereof include sulfoethyl methacrylate. The acid group may be introduced by using the above-mentioned acid group-containing polyester, acryl, polyvinyl alcohol, epoxy or the like as a dispersion stabilizer or a surfactant during the synthesis of the polymer fine powder. These are polymerization of the above-mentioned acid group-containing monomer,
It can be produced by copolymerization or polyester synthesis using sulfophthalic anhydride as a raw material.

The halogen element is introduced by copolymerizing a halogen-containing polymerizable monomer during the synthesis of the polymer fine powder or by using a halogen-containing acryl obtained by copolymerizing the polymerizable monomer as a dispersion stabilizer or a surfactant. it can.

Examples of the halogen-containing monomer include, for example, 2,2,2
-Fluorine-containing monomers such as trifluoroethyl acrylate, 1H, 1H, 5H-octafluoropentyne acrylate, 1H, 1H, 2H, 2H-heptadecafluorodecyl acrylate and hydroxyl group-containing monomers and tetrachlorophthalic anhydride Examples of the chlorine-containing monomer such as the reaction product of Examples of vinyl compounds include vinyl acetate and vinyl propionate. Furthermore, examples of the diene compound include butadiene and isoprene.

In addition to the above polymerizable monomer, a multi-ethylenic monomer may be blended in order to adjust the glass transition temperature and the molecular weight of the obtained particles. Examples of multi-ethylenic monomers include ethylene glycol diacrylate, ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate,
1,3-butylene glycol dimethacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, 1,4-butanediol diacrylate, neopentyl glycol diacrylate,
6-hexanediol diacrylate, pentaerythritol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate,
Pentaerythritol dimethacrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, glycerol dimethacrylate,
Examples are glycerol diacrylate, glycerol acryloxydimethacrylate, 1,1,1-trishydroxymethylethane diacrylate, divinylbenzene, meta-diisopropenylbenzene, para-diisopropenylbenzene or mixtures thereof. These multi-ethylenic monomers are usually used at 0.50% by weight with respect to the monomers, but may be used in excess of 50% by weight.

The polymerization is usually carried out using a polymerization initiator. Conventional polymerization initiators may be used. For example, benzoyl peroxide, di-t-butyl peroxide, cumene hydroperoxide, peroxides such as t-butylperoxy 2-ethylhexanoate, azobisisobutyronitrile, 2,2'-azobis (2,4 -Dimethylvaleronitrile), 2,2'-azobis (4-methoxy-2,4-dimethylvaleronitrile), dimethyl 2,2'-azobisisobutyrate and other azo compounds are solution-polymerized, bulk-polymerized, suspension-polymerized. It is used for polymerization. Further, in emulsion polymerization or seed emulsion polymerization, 2,2'-azubis (2-amidinopropane) dihydrochloride, 2,2'-azobis (N, N '
-Dimethylene isobutylamidine), 2,2 '-(N, N'-
Introducing an amino group by using a polymerization initiator such as dimethyleneisobutylamidine) dihydrochloride leads to the initiation of polymerization such as 4,4′-azobis (4-cyanopentanoic acid), potassium persulfate and ammonium persulfate. An acid group can be introduced by using an agent. These are used alone or as a mixture of two or more.

The fine powder according to the present invention is not limited to using only one type, and a plurality of types can be used in combination. The fine powder according to the present invention can be used in combination with other additives.

The average particle size of the fine powder according to the present invention needs to be smaller than the average particle size of the toner powder, but is preferably 0.01 to 5 μm.
Those having a particle size of m, more preferably 0.02 to 2 μm give good results.

The addition amount of the fine powder according to the present invention is 0.01-10 with respect to the toner.
% By weight, preferably 0.05 to 2.0% by weight, gives good results.

The developer of the present invention is a mixture of a known toner in addition to the above-mentioned polymer or copolymer additive, and the binder resin used in this toner includes a styrene resin and an olefin resin. , Acrylic resin, vinyl ketone resin, polyester resin, and the like. The toner may be colored if necessary. Also, a magnetic toner containing a magnetic material can be used. A toner having an average particle size of less than about 30 μm, preferably 3 to 20 μm can be used, but the toner is not particularly limited.

The developer of the present invention in which the above-mentioned additives are mixed is a so-called two-component developer having a carrier and a toner,
A so-called one-component developer which does not use a carrier may be used.

The developer of the present invention can develop an electrostatic latent image formed on a photoconductor or an electrostatic recording material. That is, an electrostatic latent image is electrophotographically formed on a photoreceptor made of an inorganic photoconductive material such as selenium, zinc oxide, cadmium sulfide, or amorphous silicon, or an organic photoconductive material such as a phthalocyanine pigment or a bisazo pigment, or polyethylene. An electrostatic latent image is formed on a electrostatic recording body having a dielectric material such as terephthalate by a needle electrode or the like, and the electrostatic latent image is formed on the electrostatic latent image by a developing method such as a magnetic brush method, a cascade method or a touchdown method. A developer is attached to form a toner image. This toner image is transferred to a transfer material such as paper and then fixed to form a copy, and the toner remaining on the surface of the photoconductor or the like is cleaned. As the cleaning method, various methods such as a blade method, a brush method, a web method and a roll method can be used.

(Effects of the Invention) The developing ability of the developer, especially the triboelectric charging ability, gradually decreases. In particular, in the case of a developer using a conventional additive,
This drop was likely to occur. However, the developer according to the present invention hardly causes a decrease in developing ability, and even after copying 50,000 sheets, there is almost no decrease in copy image density. In particular, it has a characteristic that it is not affected even in an environment of high temperature and high humidity, and this is considered to be because the zwitterionic group has a buffering effect that does not lower the function of the charge control group by adsorbing water under high humidity. Further, when cleaning the toner remaining on the photoreceptor or the like, according to the developer containing the fine powder of the present invention,
Even if 50,000 copies are copied, cleaning failure does not occur. On the other hand, in the case of the developer using the conventionally known additive, sufficient cleaning can be performed in the initial stage, but the cleaning performance gradually deteriorates, and
When the number of sheets exceeds 30,000, toner remains in an image form on the photoconductor, and afterimages or band-shaped black streaks occur in the next copy. Especially under high temperature and high humidity, the same phenomenon occurs even when the number of copies is smaller. Furthermore, it is recognized that the photoconductor is not easily damaged and that toner filming does not occur.

(Examples) The present invention will be described in more detail with reference to examples. The present invention is not limited to these examples.

Reference Example 1 (Production of Fine Particles) 400 parts by weight of deionized water was added to a 1-separable flask equipped with a stirrer, a thermometer, a N ₂ introducing tube, a condenser, and a dropping port, and the temperature was raised to 80 ° C. Add 2.2 parts by weight of an aqueous solution prepared by dissolving 0.2 parts by weight of dimethylethanolamine and 2 parts by weight of azobiscyanovaleric acid in 20 parts by weight of deionized water.
After standing for 0 minutes, 12 parts by weight of N, N-dimethyl-N-methacryloxyethyl-N- (3-sulfopropyl) -ammonium-betaine prepared separately from the aqueous solution was added to deionized water.
Liquid dissolved in 48 parts by weight, and further methyl methacrylate 10
A mixed solution of 4 parts by weight, 68 parts by weight of n-butyl acrylate, and 16 parts by weight of ethylene glycol dimethacrylate was added dropwise over 2 hours. After the completion of dropping, the temperature was kept at the same temperature for 2 hours to obtain an emulsion having a nonvolatile content of 29.6% and an average particle diameter of 0.3 micron. Water was removed from this using a freeze dryer to prepare sulfobetaine-containing acrylic resin particles.

Reference Example 2 (Production of Fine Particles) Using the same synthesizer as in Reference Example 1, 370 parts by weight of deionized water was added and the temperature was raised to 80 ° C. 2,2 in 20 parts by weight of deionized water
After adding an aqueous solution in which 2 parts by weight of azobis (2-amidinopropane) dihydrochloride was dissolved and allowing to stand for 5 minutes, 22 parts by weight of separately prepared 1- (3-sulfopropyl) -2-vinylpyridinium betaine was removed. 12 parts by weight of a mixed solution of 15 parts by weight dissolved in 198 parts by weight of ionized water, 122 parts by weight of styrene, 16 parts by weight of n-butyl methacrylate, 36 parts by weight of n-butyl acrylate and 4 parts by weight of dimethylaminoethyl methacrylate. Parts were added. After keeping for 10 minutes, the above two solutions were added separately over 1 hour,
When kept at the same temperature for 3 hours, an emulsion having a nonvolatile content of 25.2% and an average particle size of 0.1 micron was obtained. The water was removed from this using a freeze dryer to prepare acrylic resin particles containing a sulfobetaine group, an amino group, and an amidino group.

Reference Example 3 (Production of fine particles) 213 parts by weight of dihydroxyethyl taurine, 208 parts by weight of neopentyl glycol, 296 parts by weight of phthalic anhydride, 404 parts by weight of sebacic acid and 34 parts by weight of xylene were used to obtain an acid value of 164 mg by a conventional polyester synthesis method. After reacting up to KOH / g, add 500 parts by weight of Cardura E (Shell Chemical Co., Versatic acid glycidyl ester) to obtain acid value of 49 mg KO
The reaction was carried out to H / g to obtain a polyester resin containing an aminosulfonic acid type zwitterionic group. 22.5 parts by weight of this polyester resin, 2.3 parts by weight of dimethylethanolamine, and 440 parts by weight of deionized water were added to the same synthesizer as in Reference Example 1 and heated to 83 ° C. 127 parts by weight of styrene, n
A mixture of 69 parts by weight of butyl acrylate and 84 parts by weight of ethylene glycol dimethacrylate and 2.8 parts by weight of ammonium persulfate prepared separately in 28 parts by weight of deionized water was added dropwise over 2 hours. After the completion of the dropping, the temperature was kept at the same temperature for 2 hours to complete the reaction.
An emulsion with 38.7% and an average particle size of 0.08 micron was obtained. The water was removed from this using a freeze dryer to prepare acrylic resin particles containing an aminosulfonic acid type zwitterionic group, a sulfonium group and a carboxyl group.

Reference Example 4 (Production of fine particles) Using the same synthesizer as in Reference Example 1, 464 parts by weight of deionized water and 13 parts by weight of N-octadecyl-2-alanine were added.
The temperature was raised to 80 ° C. An aqueous solution prepared by dissolving 0.3 parts by weight of dimethylethanolamine and 2.6 parts by weight of azobiscyanovaleric acid in 60 parts by weight of deionized water was added dropwise over 2 hours. After 10 minutes from the beginning of the dropping of the aqueous solution, a mixed solution of 150 parts by weight of methyl methacrylate, 64 parts by weight of 2-ethylhexyl acrylate, 7 parts by weight of dimethylaminopropyl methacrylamide, and 39 parts by weight of neopentyl glycol dimethacrylate prepared separately was added dropwise. It was added dropwise in 1 hour and 30 minutes. Then, the same temperature was maintained for 2 hours to complete the reaction. An emulsion having a nonvolatile content of 32.2% and an average particle size of 0.25 micron was obtained. Water was removed from this by a lyophilizer to prepare acrylic resin particles containing amino acid type zwitterionic groups, amino groups and carboxyl groups.

Reference Example 5 (Production of Fine Particles) Using the same synthetic resin as in Reference Example 1, 434 parts by weight of isopropyl alcohol, 214 parts by weight of deionized water, and 5.6 parts by weight of mercaptoized polyvinyl alcohol were added, and the temperature was raised to 75 ° C. To this, a solution prepared by dissolving 2.4 parts by weight of benzoyl peroxide in 67 parts by weight of styrene and a solution prepared by dissolving 3 parts by weight of N-methyl-N- (vinylbenzyl) taurine in 30 parts by weight of deionized water were added, and the mixture was kept for 2 hours. After standing, the temperature was raised to 85 ° C. and the reaction was continued for 16 hours to obtain a resin dispersion liquid having a nonvolatile content of 10.1% and an average particle diameter of 0.8 micron. This was filtered, washed with water, and then water was removed by a freeze dryer to prepare styrene resin particles containing an aminosulfonic acid type zwitterionic group.

Reference Example 6 (Production of Fine Particles) 213 parts by weight of dihydroxyethyl taurine, 320 parts by weight of 1,9-nonanediol, 308 parts by weight of hexahydrophthalic anhydride, 376 parts by weight of azelaic acid, and 36 parts by weight of xylene were prepared by a conventional polyester synthesis method. Acid value to 146 mg KOH / g, and then add 250 parts by weight of Cardura E (Shell Chemical Co., glycidyl ester of versatic acid) and 114 parts by weight of allyl glycidyl ether until the acid value becomes 41 mg KOH / g. The reaction was carried out to synthesize a polyester resin having an allyl group and an aminosulfonic acid type zwitterionic group. 29 parts by weight of this polyester resin was added to dimethylethanolamine 3
Make a liquid dissolved in 20 parts by weight of deionized water and 203 parts by weight,
While stirring, a mixed solution of 106 parts by weight of styrene, 21 parts by weight of methyl methacrylate, 48 parts by weight of n-butyl acrylate, 60 parts by weight of trimethylolpropane trimethacrylate and 5 parts by weight of diethylaminoethyl methacrylate was added to form a pre-emulsion. It was Using the same synthesizer as in Reference Example 1, adding 368 parts by weight of deionized water
The temperature was raised to 8 ° C. Separately prepared 2,2'-azobis [N-
A solution prepared by dissolving 2.4 parts by weight of (4-aminophenyl) -2-methylpropionamidine] tetrahydrochloride in 36 parts by weight of deionized water and the pre-emulsion prepared above were added dropwise over 45 minutes, and then at the same temperature 4 When the reaction was completed by leaving it for a period of time, an emulsion having a nonvolatile content of 30.3% and an average particle size of 0.06 micron was obtained. The water was removed from this using a freeze dryer to prepare acrylic resin particles having an aminosulfonic acid type zwitterionic group, an amino group and an amidino group.

Example 1 Styrene-acrylic copolymer resin (manufactured by Sanyo Chemical Industries,
TB-1000) 90 parts by weight Carbon black (Cabot, R330) 8 parts by weight Nigrosine 7 parts by weight, Viscole 66
5 parts by weight of 0P (manufactured by Sanyo Chemical Industry Co., Ltd., polypropylene wax) was melt-kneaded, pulverized and classified by a conventional method to obtain a toner. The volume average particle size by Coulter counter was 11.5 microns. To 100 parts by weight of this toner, 1.5 parts by weight of the sulfobetaine-containing acrylic resin particles obtained in Reference Example 1 were added and dispersed for 10 minutes with a Henschel mixer.

When this was observed with an electron microscope, fine particles adhered to the toner surface. 10 parts of iron powder to 3 parts by weight of this developer
Table 1 shows the results of measurement of the chargeability such as the average charge amount and charge distribution by the blow-off tribo method in which 0 part by weight was mixed. Further, when a continuous actual machine running test of 100,000 sheets was carried out with a copying machine, no image quality defect due to poor cleaning was recognized, and the developer was not deteriorated.

Example 2 To 100 parts by weight of the same toner as in Example 1, the amino acid type amphoteric ion machine and the amino machine obtained in Reference Example 4 and 0.8 parts by weight of acrylic resin particles containing a carboxyl group were added, and the mixture was mixed with a Henschel mixer 5 times. Dispersed for minutes. When this was observed with an electron microscope, fine particles adhered to the toner surface. Table 1 shows the measurement results of the average charge amount and chargeability obtained by mixing 100 parts by weight of iron powder with 3 parts by weight of this developer. Moreover, when a continuous actual machine running test of 100,000 sheets was conducted with a copying machine, no image quality defect due to poor cleaning was recognized and the developer was not deteriorated.

Example 3 A toner was prepared in the same manner by using 2 parts by weight of E-81 (chromium-containing dye) manufactured by Orient Chemical Co. instead of the nigrosine used in Example 1. The volume average particle size by Coulter counter was 12 microns. To 100 parts by weight of this toner, 1 part by weight of the acrylic resin particles containing the aminosulfonic acid type zwitterionic group obtained in Reference Example 5 was added,
Disperse with a Henschel mixer for 10 minutes. When this was observed with an electron microscope, fine particles adhered to the toner surface. Table 1 shows the measurement results of the average charge amount and chargeability obtained by mixing 100 parts by weight of iron powder with 3 parts by weight of this developer. Further, when a continuous actual machine running test of 100,000 sheets was carried out with a copying machine, no image quality defect due to poor cleaning was recognized, and the developer was not deteriorated.

Example 4 A toner was prepared in the same manner except that the nigrosine used in Example 1 was removed. To 100 parts by weight of this toner, 1.8 parts by weight of the acrylic resin particles containing the aminosulfonic acid type zwitterionic group, sulfonium group and carboxyl group obtained in Reference Example 3 were added and the mixture was mixed with a Henschel mixer.
Dispersed for 5 minutes. When this was observed with an electron microscope, fine particles adhered to the toner surface. Table 1 shows the measurement results of the average charge amount and chargeability obtained by mixing 100 parts by weight of iron powder with 3 parts by weight of this developer. Further, when a continuous actual machine running test of 100,000 sheets was carried out with a copying machine, no image quality defect due to poor cleaning was recognized, and the developer was not deteriorated.

Example 5 Reference Example 6 with respect to 100 parts by weight of the toner used in Example 4
2 parts by weight of the acrylic resin particles containing the aminosulfonic acid type zwitterionic group, amino group and amidino group obtained in (2) were added and dispersed for 15 minutes with a Henschel mixer. When this was observed with an electron microscope, fine particles adhered to the toner surface. Table 1 shows the measurement results of the average charge amount and chargeability obtained by mixing 100 parts by weight of iron powder with 3 parts by weight of this developer. Further, when a 100,000-sheet continuous running test with a copying machine was conducted, no image quality defect resulting from defective cleaning was observed, and the developer was not deteriorated.

Example 6 4 parts by weight of polyvinyl alcohol (PVA-M300 manufactured by Kuraray Co., Ltd.), 0.04 parts by weight of sodium dialkylsulfosuccinate (Perex TR manufactured by Kao Co.), and 400 parts by weight of deionized water were charged in the same synthesis apparatus as in Reference Example 1. The temperature was raised to 65 ° C. To this, a mixed solution of 85 parts by weight of styrene, 15 parts by weight of 2-ethylhexyl acrylate, 10 parts by weight of IC Solvent Red 24, and 2 parts by weight of lauroyl peroxide was added and reacted for 12 hours, followed by filtration, washing with water and freeze-drying. Water was removed by a machine and classified to obtain a toner. The volume average particle diameter measured by a Coulter counter was 7 microns. To 100 parts by weight of this toner, 1.7 parts by weight of the acrylic resin particles containing the sulfobetaine group, the amino group and the amidino group obtained in Reference Example 2 were added and dispersed for 30 minutes with a Henschel mixer.

When this was observed with an electron microscope, fine particles adhered to the toner surface. Table 1 shows the measurement results of the average charge amount and chargeability obtained by mixing 100 parts by weight of iron powder with 1.8 parts by weight of this developer. Further, when a continuous actual machine running test of 100,000 sheets was carried out with a copying machine, no image quality defect due to poor cleaning was recognized, and the developer was not deteriorated.

Comparative Example 1 Iron powder 100 parts to 3 parts by weight of the toner prepared in Example 1
Table 1 shows the measurement results of the average charge amount and chargeability obtained by mixing parts by weight.
It was shown to. In addition, a running test of an actual machine was conducted, but poor cleaning frequently occurred and satisfactory image quality was not obtained.

Comparative Example 2 1 part by weight of polyethylene powder was added to 100 parts by weight of the toner prepared in Example 3 and mixed with a Henschel mixer.
Table 1 shows the results of measurement of the average charge amount and chargeability obtained by mixing 3 parts by weight of the developer dispersed for 1 minute and mixing 100 parts by weight of iron powder. When a running test was conducted on an actual machine, there was no image quality defect due to cleaning, but fog occurred from about the 50,000th sheet, and toner stain inside the machine was severe, resulting in poor image stability.

Comparative Example 3 The results of characteristics measured in the same manner as in Comparative Example 2 are shown in Table 1 except that the toner prepared in Example 4 is used. In the actual machine running test, there was a lot of fog and satisfactory image quality was not obtained.

Comparative Example 4 80 parts by weight of methyl methacrylate, 20 parts by weight of n-butyl acrylate, 4 of dimethylaminoethyl methacrylate
Parts by weight, 200 parts by weight of distilled water, 0.6 part by weight of potassium persulfate,
4 parts by weight of polyoxyethylene nonylphenol and 1 part by weight of sodium lauryl sulfate were polymerized for 4 hours by a conventional emulsion polymerization method. After the polymerization was completed, the reaction solution was cooled to 20 ° C., and an acrylic resin fine particle having an average particle size of 0.1 micron was obtained using an ultrafiltration device and a freeze dryer. To 100 parts by weight of the toner prepared in Example 1, 1 part of the fine particles was added.
Parts by weight were added and dispersed for 10 minutes with a Henschel mixer.

When this was observed with an electron microscope, fine particles adhered to the toner surface. Iron powder 100 for 3 parts by weight of this developer
Table 1 shows the measurement results of the average charge amount and chargeability obtained by mixing parts by weight.
It was shown to. In addition, a continuous running test of 100,000 sheets by a copying machine was performed, and although no image quality defect due to poor cleaning was observed, the developer stored in an environment of 30% at 80% deteriorated and was satisfactory. The image quality was not obtained.

Comparative Example 5 Acrylic resin fine particles were obtained by the same method except that the dimethylaminoethyl methacrylate used in Comparative Example 4 was removed. To 100 parts by weight of the toner prepared in Example 3, 1.3 parts by weight of the fine particles were added and the mixture was mixed with a Henschel mixer to obtain 10 parts.
Dispersed for minutes. When this was observed with an electron microscope, fine particles adhered to the toner surface. Table 1 shows the measurement results of the average charge amount and chargeability obtained by mixing 100 parts by weight of iron powder with 3 parts by weight of this developer. In addition, a continuous running test of 100,000 sheets by a copying machine was performed, and although no image quality defect due to poor cleaning was observed, the developer stored in an environment of 30% at 80% deteriorated and was satisfactory. The image quality was not obtained.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Katsuaki Takada 19-17 Ikedanaka-cho, Neyagawa-shi, Osaka Japan Paint Co., Ltd. (56) References JP 58-150969 (JP, A) JP 57-53756 (JP, A) JP 57-139111 (JP, A) JP 60-186853 (JP, A)

Claims (8)

(57) [Claims] 1. A developer containing a toner powder and a polymer fine powder having an average particle size smaller than that of the toner powder, wherein the polymer fine particles comprise (1) a zwitterionic group and (2) an amino group, A developer having a group selected from the group consisting of a group containing a silicon atom, an acid group and a halogen element. 2. A zwitterionic group is [In the formula, A represents a C _{1 to} C ₆ linear or branched alkylene group, a phenylene group, or a substituted phenylene group. ] The developer according to claim 1, which is an amino (sulfonic acid) -type zwitterionic group represented by: 3. A zwitterionic group is [In the formula, A has the same meaning as described above. ] The developer according to claim 1, which is a sulfobetaine-type zwitterionic group represented by: 4. The developer according to claim 1, wherein the polymer fine particles have an average particle diameter of 0.01 to 5 μm. 5. The polymer fine particles are added to the toner powder in an amount of 0.01-10.
The developer according to claim 1, which is added in a weight percentage. 6. A toner powder having an average particle size smaller than that of the toner powder, and the constituents thereof are (1) a zwitterionic group and (2) an amino group, a group containing a silicon atom, an acid group and a halogen element. A method for controlling charging characteristics of a toner, comprising adding a polymer fine powder having a group selected from the group consisting of 0.01 to 10% by weight based on the amount of the toner powder. 7. A zwitterionic group is [In the formula, A represents a C _{1 to} C ₆ linear or branched alkylene group, a phenylene group, or a substituted phenylene group. ] The method according to claim 6, which is a zwitterionic group of amino (sulfonic acid) type represented by: 8. A zwitterionic group is [In the formula, A has the same meaning as described above. ] The method according to claim 6, which is a sulfobetaine-type zwitterionic group represented by: