JPS61124956A - Electrostatic charge image developing color toner - Google Patents

Abstract

PURPOSE:To enhance triboelectrifiability characteristics, heat fixability characteristics, and image density by using a binder resin made of a specified vinyl type polymer contg. a positively chargeable electrostatic charge controller made of a specified compd. dispersed into the binder resin particles and having an Mw/Mn ratio of >=3.5, where Mw, Mn are each weight and number average mol.wt., respectively. CONSTITUTION:The binder resin has an Mw/Mn ratio of >=3.5, where Mw, Mn are each weight and number average mol.wt., respectively; and it is a vinyl type polymer contg. a compd., preferably, in an amt. of 0.1-10pts.wt. per 100pts. wt. of the binder resin, represented by formula [I] in which each of R<1>-R<4> is, independent of each other,. optionally substd. lower alkyl or such aryl; X is -CO- or -CnH2n<1>-; and n is an integer of 1-4. The vinyl type monomer is exemplified by styrene, m-methylstyrene, p-ethylstyrene, ethylene, propylene, vinyl chloride, etc.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a color toner for developing electrostatic images formed in electrophotography, electrostatic printing, electrostatic recording, etc. This invention relates to chargeable color toner.

[Technology background]

For example, in electrophotography, an electrostatic image is generally formed on a photoreceptor made of a photoconductive material by various means,
Next, this electrostatic charge image is developed with a toner having a charge of opposite polarity to that of the electrostatic charge image, and the resulting toner g4 is transferred to a transfer material such as paper and further fixed, thereby producing a visible image! A ti image is formed.

As described above, the toner used for developing an electrostatic image is required to have the following properties since it is used not only for developing the electrostatic image but also for the subsequent transfer and fixing steps. .

(I) Having good triboelectric properties.

That is, in order to achieve good development of an electrostatic image,
The proper polarity is achieved by the toner being in frictional contact with the carrier, for example. It is necessary to possess a charge with an amount of E as well as a proper range of bands.0(2) to have good thermal layer properties.

A contact heat fixing method is widely used to fix a toner image, in which a heated member such as a heat roller is pressed against the toner image, and a binder resin constituting the toner is melted and fixed to the transfer material. Although this contact heating fixing method has high thermal efficiency and can achieve high-speed fixing, which is particularly required in recent years, it also causes the so-called offset phenomenon due to the high temperature of the heat roller. In order to achieve good fixing, it is necessary to have a high minimum temperature at which the above-mentioned offset phenomenon occurs (hereinafter referred to as "offset occurrence temperature") and excellent non-offset properties. The toner is required to have a low minimum fixing temperature and excellent low-temperature fixing properties.

By the way, carbon black, which is used as a colorant for black toner, has a browning control effect, and charge control agents with unique colors can also be used without restrictions, so it is possible to use custom-made triboelectrification in toner. It can be said that control is relatively easy.

However, for color toners that require vivid coloring, it is generally not desirable to use charge control agents that have a unique color that would impair the tone of the toner, and it is generally preferable to use charge control agents as chromatic colorants. Since pigments or dyes themselves rarely have charge control properties, there are many restrictions on the selection of charge formation control agents.

Controlling the triboelectric properties of toner is not always easy.

In addition, in the case of color toners, chromatic colorants generally have larger particle sizes than the carbon black in black toners, and their dispersibility in the binder resin is insufficient. Almost no increase in the elastic modulus can be expected. Therefore, color toner has a higher toner bullet f when melted than black toner. E'
A problem arises in that S is low and the offset phenomenon occurs immediately.

As described above, in the case of color toners, even when selecting a binder resin, there are actually more restrictions than in terms of heat fixing properties.

[Purpose of the invention]

The present invention was made against the above-mentioned background, and its purpose is to provide a high quality image with excellent friction zone t% properties and thermal constant N properties, high image density, and no fogging. An object of the present invention is to provide a color toner for developing an electrostatic image that can stably obtain a color image.

[Structure of the invention]

The present invention is characterized in that in a color toner for electrostatic charge development which is formed by dispersing a chromatic colorant in a binder resin, the binder resin marked with # has a number average molecular fi
: Ratio of weight average molecular weight Niw to Pvin Mw/
It contains a vinyl monomer polymer having an Mn value of 3.5 or more and a compound represented by general E(I) below.

General formula (I) [empty, "i", "2% R5 and R4Fi represent a hydrogen atom, a substituted or unsubstituted lower alkyl group, or a substituted or unsubstituted aryl group, and may be the same or different Often, X is -co- or -CnH
2rr- (however, n#'' is 11.1 to 4C1 integer and is 6.

). ] The present invention will be explained in detail below.

The color toner for developing electrostatic images of the present invention has a weight average molecular weight M with respect to a number average molecular weight Mn as a binder resin.
A specific vinyl polymer having a ratio Mw/Mn of 3.5 or more is used, and particles of the binder resin are positively charged with an M coloring agent and a compound represented by the general formula (I). It is constructed by dispersing a static charge control agent and other additives added as necessary.

Examples of vinyl-based single nine bodies that can be used in the synthesis of the vinyl-based polymer include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-ethylstyrene, 2, 4-dimethylstyrene, p-n-butylstyrene, p-tert-7
'Tils fL/n, p-n-hexylstyrene% p-
”-octylstyrene, p-n-nonylstyrene% p
-n-decylstyrene, p-n-)"decylstyrene,
Preferred examples include styrene monomers such as p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, and 3,4-dichlorostyrene. In addition, ethylenically unsaturated monoolefins such as ethylene, propylene, butylene, and imbutylene; vinyl halides such as vinyl chloride, vinylidene chloride, vinyl bromide, and vinyl fluoride; vinyl acetate, vinyl fluoropionate, and benzoic acid. Vinyl esters such as vinyl acrylate, vinyl butyrate; methyl acrylate, ethyl acrylate, n-butyl acrylate, inbutyl acrylate, ethyl acrylate, n-octyl acrylate, dodefur acrylate, lauryl acrylate, 2-acrylate Ethylhexyl, stearyl acrylate, 2-chloroethyl acrylate, acrylic #
phenyl, methyl α-chloroacrylate, ethyl methacrylate, ethyl methacrylate, propyl methacrylate, inbutyl methacrylate, inbutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, methacrylic acid α-methylene aliphatic carboxylic acid esters such as lauryl, methacrylic acid, 2-ethylhexyl, stearyl methacrylate, ethyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate; acrylonitrile, methacrylonitrile, acrylamide Acrylic acid or methacrylic acid derivatives such as; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether; vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, methyl impropenyl ketone etc. tA: N-vinyl pyrrole, N-vinyl ON-vinyl compounds such as carbazole, N-vinylindole, N-vinylpyrrolidone, etc.: vinyl f7 talenes, and others. These monomers can be used alone or in combination.

In addition, in order to obtain a polymer with a ratio Mw, /Mn of 3.5 or more, (a) a method of performing "'C polymerization using a crosslinking agent," (b) a method of using multiple polymerization initiators with different half-lives, (C) a method in which the polymerization is carried out by mixing a high molecular weight polymer; (fd) a method in which the polymerization is carried out in the presence of a reactive prepolymer; Incidentally, the molecular weight of the polymer is determined by what is required for Gel Permini-7 Yon Chromatography.

As the crosslinking agent used in the method (a) above, any known crosslinking agent can be used as long as it can cause string polymerization of the monomer according to the present invention. This crosslinking agent is preferably a compound having at least two polymerizable vinyl groups. Specifically, aromatic divinyl compounds such as divinylbenzene, divinylnaphthalene, and derivatives thereof; ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, trimethylol triacrylate, allyl methacrylate, t- Butylaminoethyl methacrylate, tetraethylene glycol dimethacrylate,
All divinyl compounds such as diethylenically unsaturated carbonic acid esters such as 1,3-butanediol (11 relay), KN-divinylaniline, divinyl ether, divinyl sulfide, divinyl sulfone, etc. and compounds having three or more vinyl groups are It can be used alone or in combination of two or more t-m. Furthermore, ethylene glycol, triethylene glycol, 1,2-7'ropylene glycol, 1,3-globylene glycol, l, 4-
Butanediol, neopentyl glycol, l, 4-
Butynediol, '1,4-bis(hydroxy7methyl)
7 chlorhexane, bisphenol-A, water gi7J11
Bisphenol-A, polyoxyethylated bisphenol-human, 7-propylenated bisphenol-A in polio
Divalent fluors such as maleic acid, fumaric acid, mesaconic acid, citraconic acid, itaconic acid, glutacone R1
71krR, dibasic acids such as isophthalic acid, terephthalic acid, cyclohequinanedicarboxylic acid, succinic acid, adipic acid, sepatic acid, malonic acid, anhydrides thereof or esters with lower allols thereof, and derivatives thereof;
Trihydric or higher hydric alcohols such as glycerin, trimethylolpropane, and pentaerythritol, and trivalent or higher hydric carbon tRs such as trimetate acid and pyromellitic powder are uninventively used as crosslinking agents. The amount of such a crosslinking agent added to the monomer is selected to be in the range of 0.005 to 20% by weight, preferably 0.1 to 5% by weight.

The problem with method (b) above is that at a certain temperature, a polymerization initiator with a short half-life forms a so-called rapid initiation system, and a polymerization initiator with a long half-life forms a so-called slow initiation system. In a rapid initiation system, a polymer with a low degree of polymerization and a low molecular weight is formed, and at the same time, in a slow initiation system, a polymer with a high degree of polymerization and a high molecular weight is formed, and as a result, the ratio Mw/Mn is Polymers with a value of 3.5 or higher are obtained.

Preferred examples of polymerization initiators with short half-lives include 2.2
'-Azohis-4-methoxy-2,4-dimethylvaleronitrile % 212'-7/l: 'X-2,4-dimethylvaleronitrile and the like can be mentioned; Preferred examples include 1,1'-azobis (cyclocarbonitrile) and the like.

The prepolymers used in the method (d) above include butadiene polymer, α,W-polybutadiene homopolymer, α,ω-polybutadiene glycol, α,
Examples of polybutadiene prepolymers include ω-polybutadiene dicarboxylic acid, maleated polybutadiene, acrylic-terminated polybutadiene, and half-ester-terminated polybutadiene, which can be used alone or in appropriate combinations. .゛Such a reactive prepolymer has a molecular weight of 1 to 4 with respect to the polymerizable monomer.
0! It is sufficient if it is contained in the polymer composition in a range of 3% by weight, preferably in a range of 5 to 20% by weight.

Of course, the methods (a) to (d) above may be used in combination.

The above vinyl polymer has a Mw of 7'h! n is 3.5
Among those having the above values, in order to improve the non-offset property, it is desirable to have an M5 value of 5 or more, and in particular, one having a molecular weight of about 2,000 to 30,000 in terms of Mn! Delicious. The values of Mw, Mn and Mw/Kn can be measured by various methods, and there are slight variations depending on the measurement method. Therefore, in the present invention, 1 is defined as the value of Mw%Mn and Mw, /Mn measured by the following measuring method.

That is, all of these values are values measured by gel permeation chromatography under the conditions described below. At a temperature of 25°C, the solvent (tetrahydro 7 run) was flowed at a flow rate of 1/min, and concentrated KO, 4f/d
1, Tetrahuman I:+7 run sample solution as sample weight? Inject and measure. When measuring the molecular weight of a sample, the measurement conditions are such that the molecular weight distribution of the sample falls within a range where the logarithm of the molecular weight and the count number of a calibration curve prepared using several types of monodisperse polystyrene standard samples are linear. Select. In addition, the reliability of this measurement was determined using the NB8706 boristyrene standard sample (M
w-28,8XIO', Mix 13.7 X 10
' , M'w/Mn w 2.11) Mw/Mn is 2
．． Confirm that it is 11±0.10.

Further, the vinyl polymer has a peak molecular weight of go, o.
It is desirable to be a so-called mixed polymer consisting of a high molecular weight polymer component having a peak molecular weight in the range of oo to soo, ooo and a low molecular weight polymer component having a peak molecular weight in the range of i, ooo to 5,000. As such a polymer, a styrene-acrylic copolymer is particularly preferred. Such a mixed polymer has a polymer component ratio of 10 to 60 parts by weight, particularly 10 to 60 parts by weight, based on too and it parts of the low molecular weight polymer.
It is preferably within the range of 40 parts by weight. If this proportion is less than 10 parts by weight, the offset generation temperature will be low, and if it is 60 parts by weight or more, the softening point will be high and the minimum temperature at which fixing can be achieved will be high. Also, if the peak molecular weight of the high molecular weight IT polymer component is less than 8,000, or if the peak molecular weight of the low molecular weight polymer component is i, ooo, the offset generation temperature will not be low; When the peak molecular weight of the polymer exceeds 500,000 or the peak molecular weight of the low molecular weight polymer component exceeds 50,000i, the softening point becomes high.

The above-mentioned mixed polymer is, for example, a) such a polymer 1
A mixing method in which a polymer and a low-molecular-weight polymer are produced separately and both are melt-kneaded, or both are dissolved and mixed in a common solvent; It can be produced by a method of conducting polymerization for , and other methods, but the method described above is preferred. The magnitude of the peak molecular weight may be adjusted within the desired range by, for example, changing the polymerization conditions t'.

Furthermore, vinyl polymers as mentioned above vary depending on the type of monomers contained as constituent components, but in general, those having a softening point of about 100 to 170°C by the ring and ball method are particularly effective. Furthermore, those having a glass transition point of 40° C. or higher are particularly effective. That is, the softening point is 10
If the temperature is 0° C. or lower, excessive pulverization is likely to occur, and the photoconductive photoreceptor is likely to be contaminated due to toner filming. Furthermore, if the softening point exceeds 170° C., it is hard and difficult to crush, and furthermore, a large amount of heat is required during fixing, resulting in poor fixing efficiency. On the other hand, if the glass transition point is 40°C or lower, the storage condition of the toner is usually 40°C.
From the following, it is assumed that agglomeration due to the cold 7e+- phenomenon is the main cause.In general, the glass transition point of vinyl-based monomers has a range as the value of Mw/Mn increases, and reaches a specific value. It may be difficult to measure the glass transition point of polymers with a large value of Mw7Mn because they tend to be thin.

The above-mentioned vinyl polymers can be produced using commonly used suspension polymerization methods, bulk polymerization methods, emulsion polymerization methods, and the like.

As the compound represented by the general formula (f), the following can be exemplified.

[Exemplary compounds]

The above compounds can be used alone or in combinations of 2.11 or more. The addition ratio of such a compound to the binder resin is preferably 0.1 to 10! 'IL
%, preferably 0.5 to 5M.

The chromatic coloring agent includes various organic pigments, inorganic pigments, and various dyes, but organic pigments with clear colors, high light resistance, and high hiding properties are preferable, and examples include the following.

(Pigments are Color Index 3rd edition 1971 same supplement 19.
0) C, 1, Pigment Red 5 (Permanent Car In FB, manufactured by Hoechst Japan)
C-■・Pigment Red 48:1 (Sumikabrint V Tsudo C, made by custom chemical ■) C・Ko・Pigment Red 53:1 (Chromo 7 Tar Magenta G, Ciba Geigy #) C
- Engineering φ Pigment Red 57; 1 (Sumika Print Carin 6BC1 manufactured by Sumitomo Chemical Co., Ltd.) Ca
' I. Pigment Red 123 (Kayaset Red E-B1 Nippon Kayaku ■M) C, 1, Pigment Red 139 (Kayaset Red E-GR, Nippon Kayaku ■M) C, 1,
Pigment Red 144 (Chromophthal Red BRN, manufactured by Chinoku Geigy) C,1, Pigment Red 149 (PV Fast Red B1 manufactured by Hoechst Schatz)
C, 1, Pigment Red 166 (Chromophthal Scarlet R1 Tinoku, Geigy IA) C, 1, Pigment Red 177 (Chromophthal Blue A3B, Ten (Geigy) C, Engineering, Pigment Red 178 (Kaya) Set Red E-GG, manufactured by Nippon Kayaku ■) C・Engineering・
Pigment Red 222 (Chromo 7 Tar Red Magenta 01 Chino (Geigy M) C, 1, Pigment Orange 31 (Chromo 7 Tar Orange 4R, Chino-Geigy) C, 1, Pigment Orange 43 (Hosta Palm Orange GR, Hoechst Co., Ltd.) C, 1,
Pigment Yellow 17 (Fast Yellow GBFN, Custom Chemical Co., Ltd. J!lli C. Engineering) Pigment Yellow 14 (Benzidine Yellow OT, F Yubon Co., Ltd.) C, 1, Pigment Yellow 138 (Variotol Yellow LO960HD, Bus 7) #
) C, 1, Pigment Yellow 93 (Chromo7 Tar Yellow 3G, Chipa Geigy Company j!
iRiC・Ko・Pigment Yellow 94 (Chromo 7 Tar Yellow 6G, Ciba Geigy M)
C, Engineering, Pigment Green 7 (Crow T Near Tar Green GF, Ciba-Geigy Mluri C, 1, Pigment Blue 15:3 (Carmine Blue GNR-0, Order Kagaku) C, I
・Pigment Blue 60 (Chromo7 Tar Blue A3R, published by Ciba Geigy)
In addition to the above organic pigments, red iron oxide, titanium oxide, carbon fiber, etc. can also be used.

These chromatic colorants can be used alone or in combination of two or more. The ratio of the chromatic colorant to be used is preferably 3 to 20 times the binder resin.

As the additives added as necessary, those commonly used in toners can be used. For example, it is desirable to use various m-type agents in order to improve the non-offset properties of the toner. A certain number of such mold release agents are known, and the most preferred one is an olefin polymer.

The above-mentioned olefin polymer may be a homopolymer type obtained from a single olefin monomer, or a copolymer type obtained by copolymerizing the olefin monomer with another monomer copolymerizable with it. .

The olefin monomers include, for example, ethylene, propylene, butene-1, intene-1, hexene-1, heptene-1, octene-1, nonene-11-decene-1, and those having different positions of unsaturated bonds. isomers and those having a branched chain consisting of an alkyl group, such as 3-methyl-1-butene, 3-methyl-2-2-pentene, 3-propyl-5-methyl-2-hexene, and other Includes all olefin monomers.

Other polymers that can be copolymerized with olefin monomers include, in addition to other olefin monomers, vinyl ethers such as vinyl methyl ether, vinyl n-butyl ether, and vinyl phenyl ether; vinyl esters such as vinyl fluoride, vinylidene fluoride, tetrafluoroethylene, vinyl chloride, vinylidene chloride, haloolefins such as tetrachloroethylene, such as methyl acrylate, ethyl acrylate, n-butyl acrylate, methyl methacrylate, ethyl methacrylate,
Acrylic esters or methacrylic esters such as n-butyl methacrylate, stearyl methacrylate, N,N-dimethylaminoethyl methacrylate, t-butylaminoethyl methacrylate,
Examples include acrylic acid derivatives such as acrylonitrile, N,N-dimethylacrylamide, organic acids such as acrylic acid, methacrylic acid, maleic acid, 7-mal powder, itaconic acid, diethyl 7-malate, β-binene, etc. be able to.

Therefore, when the polyolefin component is a copolymer type, an olefin copolymer type obtained by copolymerizing at least 2 m or more of the above-mentioned olefin monomers, such as ethylene-propylene copolymer, ethylene-propylene copolymer, etc. Butene copolymers, ethylene-pentene copolymers, propylene-butene copolymers, propylene-pentene copolymers, ethylene-3-methyl-1-butene copolymers, ethylene-propynone-butene copolymers, etc.; Polymer type, or olefin copolymer type obtained by copolymerizing at least one of the above olefin monomers and at least 1 m of monomers other than the above olefin monomers, such as ethylene-vinyl acetate copolymer , ethylene-vinyl methyl ether copolymer, ethylene-vinyl chloride copolymer, ethylene-methyl acrylate copolymer, ethylene-
Methyl methacrylate copolymer, ethylene-acrylic acid copolymer, propylene-vinyl acetate copolymer,
Propylene-vinyl methyl ether copolymer, propylene-ethyl acrylate copolymer, propylene-methacrylic acid copolymer, butene-vinyl methyl ether copolymer, butene-methyl methacrylate copolymer, pentene-vinyl acetate copolymer Copolymers, hexene-vinyl butyrate copolymers, ethylene-propylene-vinyl acetate copolymers, ethylene-vinyl acetate-vinyl methyl ether copolymers, and other copolymer types can be used.

When making a copolymer type using a polymer other than an olefin monomer, it is preferable to use a copolymer type in which the proportion of the olefin moiety due to the olefin monomer in the polyolefin component is, for example, 50 mole or more. This is because if the ratio of the thin reflex portion becomes small, the effect of improving the non-offset property of the toner will not be sufficiently exhibited.

Such olefin polymers are JI8=, r2531
Those having a softening point of 100 to 180°C, particularly 130 to 160°C, as measured by the ring and ball method specified in Japan-1960 are preferred. The amount of this olefin polymer used is 1 to 10 parts by weight per 100 parts by weight of the binder resin component of the toner.
parts by weight, preferably 2 to 5 parts by weight. If the amount of the olefin polymer used is less than 1 part by weight, it will not have a sufficient anti-offset effect.On the other hand, if it exceeds 10 parts by weight, the fluidity or developability of the toner will be significantly reduced, which is undesirable.0 This invention The color toner for developing electrostatic images is produced by rolling toner components consisting of the binder resin described above, a compound represented by the general formula CI), chromatic colored ground powder, and additives added as necessary, using a heating roll or the like. The toner of the present invention can be produced by melt-kneading, cooling, pulverizing, and classifying if necessary.In addition, the toner of the present invention can be produced by not using the above-mentioned pulverizing and granulating method, but also using a suspension polymerization granulating method. It can be manufactured by engineering.

That is, a composition obtained by mixing a monomer to be formed with a binder resin and other toner components is dispersed in an aqueous dispersion medium in the presence of a dispersant (for example, polyvinyl alcohol, dotecylbenzenesulfonic acid, etc.). A spherical color toner can be obtained by polymerizing the monomers using a polymerization initiator (eg, benzoyl peroxide, azobisin butyronitrile, etc.).

Although the average particle diameter of the toner particles of the color toner for developing electrostatic images of the present invention is not particularly limited, it is preferably 5 to 20 μm.

〔Effect of the invention〕

The color toner for developing electrostatic images of the present invention uses a vinyl polymer as a binder resin, and the vinyl polymer has an M%V7'? of 3.5 or more. dnO value and contains a high molecular weight component and a low molecular weight component,
The high molecular weight component provides the toner with non-offset properties, and the low molecular weight component provides the toner with sufficient fixation at a low fixing temperature and provides good low-temperature fixing properties, resulting in excellent heat constant properties. be able to.

Further, the color toner for developing electrostatic images of the present invention has the general formula (I) having an excellent positive charging function as a charge control agent.
) is used, so it has good positive friction band resistance. Furthermore, since this compound is light-colored, it does not impair the color tone of the intended color toner.

As described above, since the color toner of the present invention uses a specific binder resin and charge control agent, the synergistic effect of the two provides excellent triboelectric charging properties and heat fixing properties, resulting in image density. It is possible to stably obtain high-quality color images with a high level of image quality and no fog.

[Embodiments of the invention]

Examples of the present invention will be described below, but the present invention is not limited thereto. Note that "parts" represent parts by weight.

Example 1 100 parts of vinyl polymer (obtained by copolymerizing styrene, methyl methacrylate, and acrylic e,n-butyl in a ratio of 75:5:20 by weight, peak molecular weight ?>1330. High OOO) A product with a peak molecular weight of 10, obtained by copolymerizing 40 parts of Kaoroku 1 combined component, and styrene, methyl methacrylate, and acrylic gl!n-butyl in a weight ratio of 70:15:15.
000 low molecular weight polymer component: MWxl 11,000, Mf1!5,500,
Mw/Mn=20.2) C0I. Pigment Red 5 EflS "Harmanent Carin FBJ (Hoechst Chaban ↓) Low molecular weight polypropylene 3 parts "Bisuru 660P
J (manufactured by Sanyo Chemical Co., Ltd.) Charge control agent
2 parts (Exemplary compound c2)) The above substances were melt-kneaded in a roll mill, cooled, and then finely pulverized in a jet mill. The resulting fine powder was classified in a zigzag classifier to obtain a color toner with an average particle size of 10 μm. . This is referred to as "toner 1".

Example 2 100 parts of vinyl polymer (copolymerized by copolymerizing styrene, methyl methacrylate, and n-butyl methacrylate in a weight/weight ratio of 50:20:30, with a peak molecular weight of 230.000) , 1,000 parts of polymer component, and 50:20 by weight of styrene, methyl methacrylate, and n-butyl methacrylate: "aOO
The peak molecular weight obtained by copolymerization on the side is 13,
Mixed resin consisting of 100 parts of a low molecular weight polymer component of 000: M! ”95.0001Mnm9.500, Mw/
Mn-1o,o) C,1, Pigment Blue 15:3
Part 7 “Sumika blintocyanine blue NR-
0” (Order Kagakusha M) Low molecular weight polypropylene
3 parts Viscoll 660PJ charge control agent 3 parts (exemplary compound (I)) The procedure was repeated in the same manner as in Example 1 using the above substances, with an average particle size of 10
A .mu.m color toner was obtained. This will be referred to as "toner 2".

Example 3 100 parts of vinyl polymer (obtained by copolymerizing styrene and n-butyl acrylate at a ratio of 80:20 by weight, with a peak molecular weight of 265,00
For 0, the molecular valuable coalescing component is 50 and styrene, methyl methacrylate, and n-butyl methacrylate are 75 in it.
: A mixed system consisting of 100 parts of a low molecular weight polymer component with a peak molecular weight of 9,100 obtained by copolymerizing at a ratio of 15:10: Mw-103,000, Mn-6
, 300, Mw/Mn=16-3) C, 1, Pigment Red 149 10 parts rPV7 Earthstred BJ (manufactured by Hoechst Japan) 2 parts low molecular weight polypropylene Viscole 660Pj Charge control agent 5 parts (exemplified compound (3)) The average particle size was 10 in the same manner as in Example 1 using
A .mu.m color toner was obtained. This will be referred to as "toner 3."

Comparative Example 1 100 parts of vinyl polymer (copolymer obtained by copolymerizing styrene, methyl methacrylate, and n-butyl acrylate in a ratio of 50:20:30 by weight: Mw = 5 o, o O01Mn -25,00
0, Mw/Mn-2, g) A color toner was obtained in the same manner as in Example 1, except that the above vinyl polymer was used instead of the vinyl 1 polymer in Example 1. This 1t-
"r comparison toner 1".

Comparative Example 2 A color toner was obtained in the same manner as in Example 1 except that the charge control agent in Example 1 was not used.

This is referred to as "comparison toner 2."

5 copies each of the above toners 1 to 3, and carrier "D"
95 parts of sP-179DJ (manufactured by Dowa Iron Powder Co., Ltd.) were mixed to prepare two-component developers.

Using these developers, an anthrone pigment as CGM (carrier generation layer) and CTM (carrier transfer layer)
Negatively charged two-layer structure O using a carbazole derivative as
An electrophotographic copying machine equipped with a PC photoreceptor ~-Bixe'' (
Using a modified machine (manufactured by Konishiroku Photo Industry Co., Ltd.), the temperature was 30℃ and the relative humidity was 80%, and the temperature was 10℃ and the relative humidity was 20%.
When images were taken in this atmosphere, clear images with no capri were obtained in either case. Next, when 20,000 sheets were continuously copied in an atmosphere of 20°C and 50% relative @fake, clear images with no misalignment or capri were obtained even after 20,000 copies, and the developer No fatigue was observed. Furthermore, there was no toner scattering and no contamination of equipment was observed.

On the other hand, when a developer similar to that described above was prepared using Comparative Toner 2 and an image was produced under the same conditions, an image with low image density and blurring was obtained.

Furthermore, the lowest fixing temperature and offset occurrence temperature were determined for each of Toners 1 to 3 and Comparative Toner I. Regarding the minimum fixing temperature, we used a heat roller whose surface layer was made of Teflon (polytetrafluoroethylene manufactured by DuPont) and
Toner gRt - Linear velocity 1 of the sample toner transferred onto a 6497 m2 transfer paper using a fixing device consisting of a pressure roller formed by 0RTYJ ((II! Kagaku Kogyo Co., Ltd.))
The fixing operation at 20 m/sec was repeated by increasing the set temperature of the heat roller by 5 degrees Celsius from 140 degrees Celsius, and the formed fixed image was rubbed and rubbed to ensure sufficient durability. The lowest fixing temperature was set as the lowest setting temperature for a fixed image exhibiting abrasion properties.

Note that the fixing device used here does not have a silicone oil supply mechanism.

Regarding the offset occurrence temperature, in accordance with the measurement of the minimum fixing temperature, the toner image is transferred and fixed by the above-mentioned fixing device, and then a blank transfer paper is sent to the fixing device under the same conditions. The operation of observing whether or not toner staining occurred was repeated while the set temperature of the heat roller of the fixing device was successively increased, and the lowest set temperature at which toner staining occurred was taken as the offset occurrence temperature.

The above results are shown in Part 1.

From the results shown in Table 1, it is clear that the toners according to the present invention have a low minimum fixing temperature and a high offset generation temperature, and therefore have a wide fixable temperature range and excellent constant N properties, and are superior to Capri. It is possible to stably form clear images. On the other hand, the toner in Comparative Example 1 was M
Since the value of w/Mn is outside the range of the present invention and is too small, there is no fixable area and it is not practical. In addition, since the toner produced in Comparative Example 2 does not contain a charge control agent, the quality of the resulting image is extremely low, which is also not practical.

Claims (1)

[Scope of Claims] 1) In a color toner for developing an electrostatic image formed by dispersing a chromatic colorant in a binder resin, the binder resin has a ratio Mw/Mn of a weight average molecular weight Mw to a number average molecular weight Mn. 1. A color toner for developing electrostatic images, comprising a vinyl polymer having a value of 3.5 or more, and further containing a compound represented by the following general formula (I). General formula (I) ▲ Numerical formulas, chemical formulas, tables, etc. are available▼ [In the formula, R_1, R_2, R_3 and R_4 represent a hydrogen atom, a substituted or unsubstituted lower alkyl group, or a substituted or unsubstituted aryl group, They may be the same or different, and X represents -CO- or -CnH_2_n- (where n is an integer from 1 to 4). ] 2) The binder resin contains a high molecular weight polymer component with a peak molecular weight in the range of 8 x 10^4 to 5 x 10^5, and a high molecular weight polymer component with a peak molecular weight in the range of 1 x 10^3 to 5 x 10^.
4. The color toner for developing electrostatic images according to claim 1, which is a styrene-acrylic copolymer comprising a polymer component having a low molecular weight within the range of 4.