JPH01201672A - Toner for developing electrostatic charge image - Google Patents

Abstract

PURPOSE:To provide a toner having excellent of set resistance without impairing flowability and fixability by incorporating a copolymer mixture which varies in the compounding ratio of monomers in a 5-40wt.% range between the respective copolymers and has 2.0-3.0 deg. of dispersion as a binder resin into the toner. CONSTITUTION:This toner contains at least >=2 kinds of the copolymers respectively having 1.5X10<4>-5X10<4>, more preferably 2X10<4>-4X10<4> number average mol.wt. and 3X10<4>-14X10<4>, more preferably 5X10<4>-10X10<4> weight average mol.wt. and have 2.0-3.0 deg. of dispersion. The copolymers incorporated into the copolymer mixture are respectively required to contain at least one common monomer as the constituting component and to have the compounding ratios of the monomers respectively varying in the 5-40wt.% range between the copolymers. The region where both the fixability and the offset resistance are good is thereby widened and the flowability of the toner is improved.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to a toner for developing electrostatic images used in the field of electrophotography, and more specifically to a toner for developing electrostatic images suitable for a hot roll fixing method in the field. Regarding toner.

(Prior art) The electrophotographic method is described in US Patent No. 2,297,691, British Patent No. 1,165,406 and British Patent No. 1.16.
As described in No. 5,405.

A charging process that uses a photoconductive substance to apply an electrostatic charge to the photoreceptor, an exposure process that irradiates light to form an electrostatic latent image, a development process that attaches toner to the latent image area, and a toner image support. Transfer process to transfer onto the body.

From the fixing step of fixing the toner image to the image support using heat, pressure, flash light, etc., the cleaning step of removing toner remaining on the photoreceptor, and the static charge removal step of removing static charge on the photoreceptor and returning it to its initial state. However, these steps are repeated to obtain a number of printed materials.

Toners for developing electrostatic images used in the field of electrophotography include toners using polystyrene resin (Japanese Patent Publication No. 44-
16118), toners using styrene/acrylic resins such as toners using styrene-butyl methacrylate copolymer resin (Japanese Patent Publication No. 11143/1983), and bisphenol-type epoxy resins obtained by reacting bisphenol with epichlorohydrin. Toners using a polyester resin obtained by reacting a glycol having a bisphenol skeleton with a polybasic acid (Japanese Patent Publication No. 52-25420) are known. Although it is.

Compared to other resins, styrene/acrylic resin can be controlled over a wide range of resin properties such as molecular weight, glass transition point, and melt viscosity, which is extremely advantageous in toner design, so the majority of toners are made using styrene/acrylic resin. It is occupied by the used toner.

(Problems to be Solved by the Invention) The hot roll fixing method involves passing a support such as paper or mylar carrying a toner image between a heated hot roll and a backup roll, and applying heat and pressure between the rolls. This method is a method of melting a toner image and firmly adhering it to a support such as paper or Mylar.This method has the feature of high thermal efficiency and has become the mainstream fixing method. However, in this method, when the support carrying the toner image passes through the heated roll, a part of the toner image is transferred to the heated roll, and then the transferred toner image is transferred again to the passing support, resulting in contamination. There is a problem that so-called offset is likely to occur.

Toner mixed with low molecular weight polypropylene has been proposed as one method for preventing offset (% Kosho 52-
Publication No. 3304). However, in order to exhibit sufficient offset resistance, it is necessary to contain a large amount of polypropylene, but this results in extremely poor fluidity of the toner, making it impractical. In addition, as another method for preventing offset, a low molecular weight resin and a high molecular weight resin were used together.

That is, the degree of dispersion (weight average molecular weight/number average molecular weight) 11
8651, JP-A-50-134652).

However, with these, there are problems such as a decrease in fixing performance due to the use of high molecular weight resins and a decrease in toner toughness due to the use of low molecular weight resins, which means that a satisfactory toner cannot be obtained. The reality was that there was no such thing.

The present invention solves the above-mentioned problems, and a first object thereof is to provide a toner that has no problems in fluidity and fixing properties and has excellent offset resistance.

A second object of the present invention is to provide a toner with excellent fluidity and fixing properties.

A third object of the present invention is to provide a long-life toner that can maintain the print density and capri resistance necessary for a toner for a long period of time.

(Means for Solving the Problems) The present invention has a number average molecular weight of 1.5 x 10' to 5 x
10' to weight average molecule 13 x 104 ~ 14 x 10'
and a dispersity of 2.0, each copolymer has at least one common monomer as a constituent component, and the blending ratio of the monomers is A toner for developing electrostatic images, characterized in that the binder resin contains a copolymer mixture having a dispersity of 2.0 to 3.0, which differs by weight in the range of 5 to 40 among the copolymers. Regarding.

The copolymer mixture in the present invention has a number average molecular weight of 1.5
X104~5x104, preferably 2X104~4
X 104 and 9 weight average molecule j13X1g4~1
4X104. Preferably 5 x 104 to 10 x 104
Adashi.

A copolymer having a dispersity of zO ~ 3.0 is at least
' also contains two or more types. If the average molecular weight of each copolymer is outside this range, both fixing properties and offset resistance may be achieved.
It is not possible to obtain a binder resin that is effective for high fluidity and long life. 9 In the present invention, different types of copolymers refer to at least one of the constituent monomer components.
Even if the species or more of the constituent monomers are the same, the blending ratio of each monomer is different.

At least 2 contained in the copolymer mixture in the present invention
The above-mentioned copolymers of more than one type each have at least one common monomer as a constituent component, and the blending ratio of the monomers is in the range of 5 to 40% by weight between the respective copolymers. It is necessary to be different. If this value is less than 5% by weight, the balance between fixing properties and anti-offset properties is poor, and if it exceeds 40% by weight, the fixing properties are poor and the toner particles tend to aggregate, making it impossible to maintain the essential characteristics of a toner. It disappears.

When the copolymer mixture is composed of two types of copolymers, the difference in the blending ratio of common constituent monomers is preferably in the range of 5 to 20% by weight.

In addition, in the case of copolymers of class 3a or higher, the difference in the blending ratio of common constituent monomers must be within the range of 5 to 40% by weight between the most distant copolymers. There is.

In the copolymer mixture, each copolymer is blended in an amount of at least 5% by weight, preferably 10% by weight or more. If the amount of each copolymer is too small, it tends to be difficult to achieve both fixing properties and anti-offset properties. In addition, the mutual ratio of the copolymers in the copolymer mixture is 70/70 when the difference in the blending ratio of common constituent monomers is 10% by weight or less from the viewpoint of the balance between fixing properties and anti-offset properties. 30 to 30/70 (weight ratio) is preferable.

More than 10% by weight and less than 20% by weight: 80/20~
20/80 (weight ratio) is preferred, and those exceeding 20% by weight are preferably 9515 to 5/95.

Note that the number average molecular weight and weight average molecular weight in the present invention refer to values measured by the Tohakel permeation chromatography method and determined using a standard polystyrene calibration curve. Further, the degree of dispersion is determined by dividing the measured weight average molecular weight by the number average molecular weight.

Each polymer of the present invention is produced by copolymerizing 9 polymerizable unsaturated monomers described below, for example.

The polymerizable unsaturated monomers are listed below, but the present invention is not limited thereto.

(al Styrene derivatives such as styrene, α-methylstyrene, p-methylsnarene, pt-butylstyrene, p-chlorostyrene, hydroxystyrene, etc. (b) Methyl methacrylate, ethyl methacrylate.

Propyl methacrylate, butyl methacrylate, pentyl methacrylate, hexyl methacrylate, heptyl methacrylate, octyl methacrylate, nonyl methacrylate,
Decyl methacrylate, undecyl methacrylate, dodecyl methacrylate, tridecyl methacrylate, pentadecyl methacrylate.

Cetyl methacrylate, octadecyl methacrylate.

Tocosyl methacrylate, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, pentyl acrylate, hexyl acrylate, butyl acrylate, octyl acrylate, nonyl acrylate, decyl acrylate, undecyl acrylate, acrylic acid Acrylic acid alkyl esters and methacrylic acid alkyl esters (C) such as dodecyl, tridecyl acrylate, pentadecyl acrylate, cetyl acrylate, octadecyl acrylate, tocosyl acrylate, etc. Others having one copolymerizable unsaturated group in the molecule Copolymerizable monomers 9 such as glycidyl methacrylate, methoxyethyl methacrylate, propoxyethyl methacrylate, butoxyethyl methacrylate, methoxydiethylene glycol methacrylate, ethoxydiethylene glycol methacrylate, and methoxyethylene glycol methacrylate.

Butoxytriethylene glycol methacrylate.

Methoxydipropylene glycol methacrylate.

Phenoxyethyl methacrylate, phenoxydiethylene glycol methacrylate, phenoxytetraethylene glycol methacrylate, benzyl methacrylate, cyclohexyl methacrylate, tetrahydrofurfuryl methacrylate, dicyclopentenyl methacrylate, dicyclopentenyloxyethyl methacrylate,
N-vinyl-2-pyrrolidone, methacrylonitrile, methacrylamide, N-methylolmethacrylamide, 2-hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxybutyl methacrylate, 2-hydroxy-3-phenyloxypropyl methacrylate,
Phthalimidoethyl memethacrylate, phthalimidopropyl methacrylate, morpholinoethyl methacrylate, morpholinopropyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, diacetone methacrylamide, glycidyl acrylate.

Methoxyethyl acrylate, propoxyethyl acrylate, butoxyethyl acrylate, methoxydiethylene glycol acrylate, ethoxydiethylene glycol acrylate, methoxyethylene glycol acrylate, butoxytriethylene glycol acrylate, methoxydipropylene glycol acrylate, phenoxyethyl acrylate.

Phenoxydiethylene glycol acrylate, phenoxytetraethylene glycol acrylate.

Benzyl acrylate, cyclohexyl acrylate.

Tetrahydrofurfuryl acrylate, dicyclopentenyl acrylate, dicyclopentenyloxyethyl acrylate, N-heal-2-pyrrolidone acrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxybutyl acrylate, 2-hydroxy acrylate -3-phenyloxypropyl, glycidyl acrylate, acrylonitrile, acrylamide, N-methylolacrylamide, diacetone acrylamide.

Vinylpyridine, phthalimidoethyl acrylate.

Phthalimidopropyl acrylate, morpholinoethyl acrylate, morpholinopropyl acrylate.

Dimethylaminoethyl acrylate, diethylamineethyl acrylate, acrylic acid, methacrylic acid.

maleic acid, fumaric acid, mesaconic acid, -1'conic acid,
citraconic acid, diethyl fumarate, diptyl fumarate,
Dioctyl fumarate etc.

(d) It has two or more copolymerizable unsaturated groups in the molecule. Other polymerizable unsaturated monomers 9 such as divinylbenzene, reaction products of glycol and methacrylic acid or acrylic acid 9 such as ethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate,
1.4-butanediol dimethacrylate, 1.5-bentanediol dimethacrylate, 1.6-hexanediol diacrylate, neopentyl glycol dimethacrylate, diethylene glycol dimethacrylate.

Triethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, tripropylene glycol dimethacrylate, hydroxypivalic acid neopentyl glycol ester dimethacrylate, trimethylolethane trimethacrylate, trimethylolpropane trimethacrylate, pentaerythritol trimethacrylate.

Pentaerythritol tetramethacrylate, trismethacryloxyethyl phosphate, bis(methacryloyloxyethyl)hydroxyethyl isocyanurate, tris(methacryloyloxyethyl)isocyanurate, ethylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,4- Butanediol diacrylate, 1.5-bentanediol diacrylate, 1゜6-hexanediol diacrylate, neopentyl glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, polyethylene glycol diacrylate, tripropylene diacrylate, hydroxy Neopentyl glycol pivalate diacrylate, trimethylolethane triacrylate, trimethylolpropane triacrylate.

Pentaerythritol triacrylate, pentaerythritol tetraacrylate, trisacryloxyethyl phosphate, bis(methacryloyloxyethyl)hydroxyethyl isocyanurate, tris(methacryloyloxyethyl)in cyanurate, glycidyl methacrylate and methacrylic acid or acrylic acid. --7 esterified product.

A half ester of bisphenol type epoxy resin and methacrylic acid or acrylic acid, a half ester of glycidyl acrylate and methacrylic acid or acrylic acid.

Each copolymer in the present invention is preferably a styrene-acrylic copolymer containing the styrene derivative of (al) and the alkyl acrylate and/or alkyl methacrylate of (b).

More preferably, the ratio thereof is (a)/(bl is 90/
10 to 30/70 (weight ratio), preferably 80/70 to 9%
It has a weight ratio of 20 to 40/60. Outside this range, it tends to be difficult to maintain the necessary performance (environmental resistance, fixability, etc.) as a toner. The polymerizable unsaturated monomer (C) is preferably used in an amount of 0 to 40% by weight based on the total monomers constituting each copolymer. The polymerizable unsaturated monomer (d) is preferably used in an amount of 0 to 5% by weight based on the total monomers constituting each copolymer.

In the present invention, styrene, butyl acrylate,
Butyl methacrylate, octyl acrylate, octyl methacrylate, diptyl fumarate.

It is preferable to use a copolymer containing monomers such as phthalimidoethyl acrylate and phthalimidoethyl methacrylate as constituent components.

The above monomers can be polymerized in suspension, solution, or in bulk.

Each copolymer gold can be obtained by copolymerizing by any known method such as emulsion polymerization.

In the polymerization of the polymerizable unsaturated monomer, the polymerization initiator used is 42'-azobisisobutyronitrile,
Azo-based compounds such as 42'-azobis-(2,4-dimethylvaleronitrile), 2,2'-azobis(4-methoxysheath 4-dimethylvaleronitrile), t-butylperoxy(2-ethylhexanony) ), peroxy esters such as 1-butylperoxyisobutyrate, 1.1-
Bis(t-butylperoxy)3,3.5-)riftylcyclohexane. Peroxy ketals such as 1.1-bis(1-butylperoxy)cyclohexane, dicumyl peroxide, dialkyl peroxides such as 2.5-dimethyl-45-di(1-butylperoxy)hexane, benzoyl peroxide , diacyl peroxide such as acetyl peroxide. These are preferably used in an amount of 0.5 to 10% by weight based on the total polymerizable unsaturated monomers.

The resulting copolymer mixture is used as a binder resin for toners in the present invention.

In the present invention, binder resin components other than the above copolymer mixture can also be used in combination. Such binder resins include other vinyl resins, silicone resins, polyester resins, and epoxy resins.

Phenolic resin, xylene resin, coumaron resin.

There are known resins such as amide resins and diene resins.

When these are used together, 50ii of the total binder resin components
It is preferable that the amount is less than 1% by weight, more preferably less than 20% by weight, particularly less than 10% by weight.

The toner according to the present invention contains a colorant and/or magnetic powder. The colorant is carbon black.

Black fabric colorants such as acetylene black, lamp black, graphite, iron black, aniline black, cyanine blank, yellow lead, cadmium yellow, yellow iron oxide, titanium yellow, naphthol yellow, hump yellow, hyment yellow, benzidine yellow .

Permanent yellow, quinoline yellow lake.

Yellow coloring agents such as Acis Labrimidine Yellow, Permanent Orange, Palcan Fast Orange.

Benzidine Orange, Indan Lenz IJ IJ 7
Orange colorants such as orange, iron oxide, and amber.

Brown colorants such as permanent brown, red iron.

Red colorants such as antimony powder, hermanent red, fire red, brilliant carmine, light fast red toner, permanent carmine, pyrazolone red, Bordeaux, heliobordeaux, rhodamine lake, thioindigo red, thioindigo reddon, cobalt purple, fast Purple colorants such as violet and dioxazine violet, cobalt blue, cerulean blue,
Metal-free phthalocyanine blue, phthalocyanine blue,
There are blue colorants such as indanthremble and indigo, green colorants such as chrome green, cobalt green, green gold, phthalocyanine green, polychrome bromine copper phthalocyanine, and carbon black when heat decomposition resistance is required. , iron black, cyanine black, yellow iron oxide.

Titanium Yellow, Hansa Yellow, Benzidine Yellow.

Permanent Orange, Palkan Fast Orange, #
! Ferrite, red iron, firelet, light fast red toner, permanent carmine.

Pyrazolone Red, Bordeaux, Thioindigo Maroon,
Particularly preferred are cobalt purple, cobalt blue, cerulean blue, phthalocyanine blue, cobalt green, phthalocyanine green, polychrome bromine copper phthalocyanine, and the like. These colorants are blended in an amount of 1 to 60% by weight in the total toner components.

If it is less than 1% by weight, the coloring will be opaque, and if it exceeds 60% by weight, the fixing properties of the toner tend to deteriorate.

Magnetic powders include metal powders such as iron, manganese, nickel, and cobalt, as well as aluminum and cobalt.

Steel, lead, magnesium, nickel, tin, zinc.

antimony, beryllium, bismuth, cadmium.

Alloys and mixtures of metals such as calcium, manganese, selenium, titanium, tungsten, vanadium, metal oxides such as aluminum oxide, iron oxide, steel oxide, nickel oxide, zinc oxide, titanium oxide, magnesium oxide, chromium oxide or alloys that exhibit ferromagnetism when heat treated.

Examples Whisker alloys such as evaporated manganese-copper-aluminum, manganese-copper-tin, etc. can be used. The particle size of the magnetic powder is preferably 10 μm or less.

In particular, the thickness is preferably 1 μm or less. These magnetic powders are contained in the toner in an amount of 30-70% by weight. When using magnetic powder, the above-mentioned colorant may be further added, and the amount thereof is preferably 100 weight or less in the toner.

A charge control agent can be appropriately added to the toner according to the present invention. Charge control agents include nigrosine dyes, fatty acid-modified nigrosine dyes, resin-modified dirosine dyes, tetraalkylammonium halides, and trialkylammonium halides.

A compound of the formula: (wherein X' represents a halogen, R represents an alkylene group having 1 to 3 carbon atoms, and n represents 0 or 1).

A nitrile compound having a structural unit of -C-C(CN)- (in the formula, R represents hydrogen or an alkyl group having 1 to 3 carbon atoms).

(In the formula, Rt represents an alkoxy group or a phenoxy group, I R3 represents hydrogen, an alkoxy group, or a phenoxy group), monoalkyltin oxide, dialkyltin oxide, monoaryltin oxide.

Formula: (In the formula, R4, R5, R4 and & are hydrogen, carbon atoms 1 to
Represents a substituent having nine alkyl groups, aromatic rings, or cyclohexene rings, but two or more groups simultaneously represent hydrogen.Me represents Cr, Co, or Fe; 9M represents hydrogen, potassium, sodium, or fatty acid ammonium. Compound 1 of formula 1: (in the formula, R8 and tortoise have 1 to 9 carbon atoms)
9 alkylene groups, aromatic rings or cyclohexene rings, Me and M are as defined above):
(In the formula, T, Y and Z represent hydrogen, - rogene, carboxyl group, hydroxyl group, nitro group, sulfone group or sulfonamide group, and 1M and Me represent the above)
, other metal-containing azo compounds, tetrathiafulvalene, fine alumina powder, and other known compounds can be used, and are usually added to the toner in an amount of 0 to 20% by weight.

The toner according to the present invention may contain known additives such as a fluidity improver, a cleaning performance improver, and an anti-offset agent, if necessary.

Fluidity improvers provide toner with high fluidity.

It facilitates the continuous supply of toner and forms visible images of good quality. Hydrophobic silica powder is most suitable as the fluidity improver. Such hydrophobic silica powder is made by combining fine powder of silicon dioxide whose surface silicon atoms are silanol groups, such as octyltrichlorosilane,
Decyltrichlorosilane, nonyltrichlorosilane, 4
-inpropylphenyltrichlorosilane, 4-t
ert-7'' tylphenyltrichlorosilane, dimethyldichlorosilane, dipentyldichlorosilane, dihexyldichlorosilane, dioctyldichlorosilane, dinonyldichlorosilane, didecyldichlorosilane.

didodecyldichlorosilane, 4-tert-butylphenyloctyldichlorosilane, dioctyldichlorosilane, didecenyldichlorosilane, dinonenyldichlorosilane, di-2-ethylhexyldichlorosilane, di-3
．． 3-dimethylpentyldichlorosilane, trimethylchlorosilane, trihexylchlorosilane, trioctylchlorosilane.

Tridecylchlorosilane, dioctylchlorosilane, octyldimethylchlorosilane, 4-isopropylene. By reacting with a compound such as bilphenyldiethylchlorosilane, a hydrophobic group is bonded to the surface silicon atoms of silicon dioxide particles via oxygen atoms.

These hydrophobic silica powders have an average particle size of 1 m11
m~100. It is preferably within the range of um, especially 2
Preferably, the thickness is between mμm and 50μm.

If it is less than 1 mμm, the powder tends to scatter and is difficult to handle, and if it exceeds 100 μm, the photoreceptor is likely to be damaged.

Such hydrophobic silica powders include Aerosil R972,
Silica D-17, R812, RA200H, R, X-C
(9 or more manufactured by Nippon Aerosil ■) and Taranox 50
0 (manufactured by Tulco), etc.

The toner may be manufactured by blending the hydrophobic silica powder as described above with other toner materials.

In particular, it is preferred to manufacture the toner in part with toner materials excluding the hydrophobic silica powder, and then add the hydrophobic silica powder.

When adding hydrophobic silica powder, hydrophobic silica powder is
It is preferably added in an amount of 0 to 15% by weight based on the toner not containing hydrophobic silica powder.

In particular, the amount added is preferably 0.1 to 10% by weight. Adding more than 15 tons does not increase the effect that much.

A part of the toner component of the cleaning property improving agent adheres to the surface of the photoreceptor or carrier. It prevents the so-called filming phenomenon and always forms clear visible images without fogging even during long-term continuous use.

Cleanability improvers include metal salts of saturated or unsaturated fatty acids such as maleic acid, stearic acid, oleic acid, palmitic acid, and caproic acid.

Linoleic acid, ricinoleic acid or ricylic acid with zinc, magnesium, calcium, cadmium.

Fine particles of salts with lead, iron, nickel, cobalt, copper or aluminum or other resins mentioned above may be mentioned, and zinc stearate, calcium stearate, magnesium stearate or resin particles of 1 to 10 μm are particularly preferred.

When a cleaning performance improver is used, it is particularly preferable that the cleaning performance improvement agent is added in the same manner as the hydrophobic silica powder described above. these are.

0 to 25% by weight based on the toner not containing the additive,
It is preferable to add KO, 1 to 10% by weight.

Even if it is added in excess of 25% by weight, the effect will not be increased.

Anti-offset agents include ethylene, propylene, butene, pentene, hexene, and heptene.

octene, nonene, decene, 3-methyl-1-butene,
Polymers of olefin monomers such as 3-methyl-2-pentene and 3-propyl-5-methyl-2-hexene, or copolymers of the above-mentioned olefin monomers with acrylic acid, methacrylic acid, vinyl acetate, etc., stearin Lower alcohol esters of fatty acids such as butyl stearate and propyl stearate.

Polyhydric alcohol esters of fatty acids such as Casta Wax (manufactured by Ito Oil Co., Ltd.), Diamond Wax (manufactured by Shin Nippon Rika Co., Ltd.), Palm Acetate (manufactured by Nippon Oil & Fats Co., Ltd.), Hoechst Wax E, Hoechst Wax-〇P (Hoechst Wax Co., Ltd.) company).

Higher alcohol ester of fatty acids such as carnauba wax, Bisamide Plast Flow (manufactured by Nitto Chemical Industry ■)
, Amide 6L, 78 and 6H (manufactured by Yoken Fine Chemicals ■), alkylene bis fatty acid amide compounds such as Hoechst Wax C (manufactured by Hoechst Akchengesellschaft), zinc stearate, calcium stearate, magnesium stearate, barium stearate, Copper stearate, aluminum stearate, zinc oleate, magnesium oleate, zinc caprylate, magnesium caprylate, zinc linoleate.

Fatty acid metal salts such as calcium linoleate, Nilapol N
Diene resins with a weight average molecular weight of 50,000 or more, such as BR, 20578, 2007J, and BR1220.

There are hydroxyl group-containing vinyl resins, carboxyl group-containing vinyl resins, and the like. The anti-offset agent is preferably added to the toner in an amount of 1 to 30% by weight based on θ to 50% by weight. When added in an amount exceeding 50% by weight, fixing properties tend to deteriorate.

In the present invention, the various additives described above may be added alone or in combination.

A toner for developing an electrostatic image can be produced by mixing the above-mentioned materials, for example, by the following method.

After pre-mixing the weighed materials using a W cone, ■ blender, Henschel mixer, etc., knead them at a temperature where the resin melts using a pressurized mixer, hot roll, extruder, etc. .After cooling, feather
Coarsely grind it with a mill, bottle mill, pulverizer, etc. Next, the particles are sieved using an Accucut, Albine classifier, etc., and adjusted to a particle size of preferably 5 to 30 μm.

When the toner according to the present invention is used in a two-component manner, the toner and carrier are combined to explode the developer.

Such carriers are flat and spongy.

Coin-shaped, hard spherical, 9-spherical iron powder, ferrite.

The surface of the iron powder or ferrite is coated with Teflon, silicon,
Preferably, the toner is coated with a thermoplastic or thermosetting resin such as vinyl, or the one-component toner of the present invention. Furthermore, the particle size, electrical resistance value, specific surface area, etc. of the carrier are adjusted depending on the purpose of use.

The toner concentration of the two-component developer generally depends on the specific surface area of the carrier, but is generally preferably 1 to 10% by weight.

The toner according to the present invention can be applied to nine different known developing methods.

Furthermore, the toner according to the present invention can be fixed using nine different fixing methods.

For example, it can be used in so-called oil-less and oil-coated heated roll methods, xenon flash irradiation methods, open methods, pressure fixing methods, and the like.

Furthermore, the toner according to the present invention can be used in various cleaning methods such as the so-called fur brush method and blade method.

(Example) Next, examples of the present invention will be shown.

(1) Production of copolymers 几-1 to 几-6 Partially saponified polyvinyl alcohol (Tenkabovar W-
24. In a reaction vessel containing 2000 parts by weight of an aqueous dispersion medium in which 3 parts by weight of Denki Kagaku Kogyo Co., Ltd.) was dissolved, 1000 parts of a polymerizable monomer having the composition shown in Table 1 and ditertiary butyl peroxide as a polymerization initiator were charged. , 80-90
The reaction was carried out at ℃ for 10 hours. The mixture was then cooled, filtered and dried to obtain copolymers R,-1 to R-6.

The number average molecular weight, weight average molecular weight, and dispersity of each copolymer are summarized in Table 1.

Note that the number average molecular weight and weight average molecular weight were determined under the conditions shown below, and the 2-dispersity was calculated from these values.

*Molecular weight measurement conditions Gel permeation chromatography method Measuring device; Hitachi model 635 ((#Newly manufactured by Hitachi Seisakusho) column: 10.
Three columns of 7o+mφ

Product name) is used.

Column pressure: 30 to 9 flon” Solvent: Tetrahydrofuran Flow rate: 2.03mI! / minute Detector; refractive index detector A calibration curve was created using monodisperse polystyrene.

Margin below (2) Production of toner (Examples 1 to 4 and Comparative Examples 1 to 2)
The toner components shown in Table 2 were dry-mixed all at once, and then melt-kneaded at 160° C. using a twin-screw kneader. After cooling, it was pulverized with jet air to obtain a toner having a particle size range of 5 to 25 μm.

(3) Evaluation: 3% by weight of each toner and an apparent density of 25 to 3.09/cm
', electrical resistance value is 108~109Ω"Cm and 44~10
A developer is prepared by mixing 97% by weight of a ferrite carrier containing 90% by weight or more of particles with a particle size of 5 μm, and an organic photoconductive photosensitive material is rotated at a circumferential speed of about 60 cm/sec using the developer. After the body is negatively charged with corona voltage, information is written using a semiconductor laser.

Reversal development was performed using a magnetic brush method. Next, the toner image carried on the recording paper was fixed using a heated roll whose temperature-variable surface was coated with Teflon.

The obtained printed matter was evaluated and summarized in Table 1.

The test method is shown below.

(1) Print density and capri density were measured using a reflection densitometer model TC-6DS manufactured by Tokyo Juishiki ■.

(11) Fixability After attaching cellophane tape (manufactured by Uzukusui Kagaku Kogyo ■) to the printed matter, the cellophane tape was peeled off and the fixing strength was calculated using the 9th equation.

[1ii1 Offset resistance The printed matter was visually judged, and those in which offset did not occur were marked as "No" and those in which offset occurred were marked as "Yes."

The friction coefficient of the toner was measured using an Ovl fluid powder shear tester (manufactured by Tsutsui Rikagaku ■). The smaller the number, the better the fluidity.

Comparative Example 3 Styrene 80w f1% and butyl acrylate 20w ii
The same aqueous @turbidity polymerization as above was carried out using 80% by weight of a low molecular weight polymer produced by the same aqueous @turbidity polymerization as above, 77% by weight of styrene, and 23% butyl acrylate. Manufactured with a number average molecular weight of 18 x 104. A high molecular weight polymer having a weight average molecular weight of 49 x 104 and a number average molecular weight of 1.6 x 104 mixed with 20% weight
87% by weight of a binder resin with a weight average molecular t20xio' and a dispersity of 12.5, carbon black≠4410% by weight, 2% by weight of Hontron 8-44, and Viscoel 660.
A toner was prepared by kneading and classifying P1 with ti% by weight under the same conditions as above. Evaluation was performed in the same manner as above, and the results are shown in Table 3.

Margin below (Effects of the Invention) As is clear from the above results, there is a wide range in which the toner for developing electrostatic images, which is advantageous to the present invention, has good fixing properties and anti-offset properties. It is a long-life toner that shows good print density and capri resistance even after repeated use over a long period of time.

Agent: Patent Attorney Kunihiko Wakabayashi

Claims (1)

[Claims] 1. A number average molecular weight of 1.5 x 10^4 to 5 x 10^4, a weight average molecular weight of 3 x 10^4 to 14 x 10^4, and a dispersity of 2.0 to 3.0. Contains at least two or more types of certain copolymers, each copolymer has at least one common monomer as a constituent component, and the blending ratio of the monomers is 5 to 40% by weight between each copolymer. 1. A toner for developing an electrostatic image, characterized in that it contains a copolymer mixture having a dispersity of 2.0 to 3.0, which differs in percentage, as a binder resin. 2. The toner for developing electrostatic images according to claim 1, wherein the copolymer is a styrene-acrylic copolymer. 3. For electrostatic image development according to claim 1 or 2, wherein the copolymer mixture is composed of two types of copolymers, and the blending ratio of common monomers differs by 5 to 20% by weight. toner. 4. The toner for developing electrostatic images according to claim 1 or 2, wherein the copolymer mixture comprises at least three types of copolymers.