JP2615912B2 - Electrostatic toner - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel toner for developing an electrostatic image in electrophotography, electrostatic recording, electrostatic printing, and the like, and more particularly, to a toner excellent in positive chargeability. About.

2. Description of the Related Art The development of an electrostatic latent image is performed by applying a negatively or positively triboelectrically charged toner to an electrostatic latent image having a positive or negative charge formed on a photoreceptor by various methods. Then, the toner image is transferred onto the transfer paper and fixed, whereby the developed image is fixed. The toner is first required to have an appropriate charge amount in order to obtain a clear developed image without fog or the like. Further, it is also required that the charge amount does not change with time and that the charge amount does not significantly change or change due to environmental changes, for example, humidity change. This is because if the charge amount attenuates from the initially set value and becomes smaller, toner scattering increases, causing problems such as background fog, toner scattering on blank paper, and toner contamination around the developing device. is there.

In order to meet the above demand, a charge control agent is usually added at the time of toner production. In recent years, colorization has been advanced, and a white or pale yellow charge control agent having excellent color reproducibility has been required.

Colorless, white, or pale yellow negative charge control agents that impart a negative charge are commercially available and have high effects, and the use of these control agents is not particularly limited in practice. However, a positive charge control agent that imparts a positive charge, particularly one that can be used for a color toner, is a colored nigrosine dye, a white quaternary ammonium salt or an imidazole compound (Japanese Patent Application Laid-Open No.
JP-A-62-287262, JP-A-61-259265 and JP-A-59-187350) are known, but the types thereof are very few.

Nigrosine dyes do not consist of a single pure compound, but are a mixture of several compounds, the exact composition and the like of which are unknown. Nigrosine dyes function effectively to impart stable charge to toners used in copying machines whose copying speed is medium to low. The above function cannot be obtained even if it is applied as it is to a toner for a copying machine. As for the color toner, there is a problem in applying the nigrosine dye because it is colored.

The quaternary ammonium salt has problems such as unstable environmental stability of charging performance, large particle size, insolubility at the time of fixing, and odor. Also, the quaternary ammonium salt is insufficient in charging performance like the nigrosine dye.

As the imidazole compound, the following formula; Diorganotin bisimidazole represented by
-287262), the following formula; 2-aminobenzimidazoles represented by
61-217055), the following formula; Vinylimidazoles represented by the formula (JP-A-59-187350)
Is known.

The charge control agent disclosed in the present application is also an imidazole compound, but is completely different from the above compound.

Problems to be Solved by the Invention As described above, a positive charge control agent that imparts a positive charge is
The number is small, and a colorless or white color toner particularly suitable for a color toner is desired.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a positively chargeable toner having excellent charge rising, stability, and environmental resistance.

Another object of the present invention is to provide a positively chargeable toner having excellent color reproducibility and excellent translucency.

Means for Solving the Problems The present invention provides the following general formula [I]; [Wherein R ₁ , R ₂ and R ₃ represent a hydrogen atom, an alkyl group, an aralkyl group or an aryl group, which may be the same or different. n represents an integer of 1 or more. ] It is related with the toner for electrostatic charge development characterized by containing the imidazole derivative represented by these.

In the general formula [I], R ₁ , R ₂ and R ₃ are a hydrogen atom, a C _{1 to} C ₃₅ alkyl group (which may be branched), an aralkyl such as benzyl or phenethyl, or an aryl such as a phenyl group. And may be the same or different.

In the general formula [I], n is an integer of 1 or more, preferably 1 to
It is an integer of 50.

Such an imidazole derivative of the present invention is useful as a charge control agent for a toner, and is particularly used as a charge control agent for a positively chargeable toner.

The imidazole derivative represented by the general formula [I] is different from the imidazole derivative represented by the general formula [II] and the general formula [II]
It can be easily synthesized by reacting the imidazole derivative represented by the formula [I] with paraformaldehyde directly or using a suitable solvent in the presence of a strong inorganic alkali catalyst; [Wherein, R ₁ , R ₂ and R ₃ are the same as described above. As the solvent used for the synthesis, alcohols such as methanol, ethanol, isopropanol, ethylene glycol monoalkyl ether and ethylene glycol are preferable. The reaction temperature depends on the type of solvent, but is 80 to 200.
C is appropriate.

Examples of the derivative represented by the general formula [I] of the present invention include the following, but are not limited thereto.

The imidazole derivative charge control agent represented by the general formula [I] can be applied to known toners, for example, a pulverized toner, a suspension polymerization toner, a capsule toner and the like. General formula [I]
The imidazole derivative represented by the formula (1) may be contained in the inside of the toner, or may be adhered and fixed on the toner surface.

When contained inside, in addition to additives such as a coloring agent, the imidazole metal compound charge control agent of the present invention is further added, and a pulverized toner, a suspension polymerization toner, a capsule toner and the like are prepared by a usual method. Good. In the case of a capsule toner, it is desirable to prepare the outer shell layer so as to contain the charge control agent.

Further, in an embodiment in which the charge control agent is attached to the surface portion of the outer shell layer, the charge control agent is attached to the toner surface by the action of van der Waals force and electrostatic force, and then is fixed by mechanical impact force or the like. Good.

Apparatuses that can be suitably used in such a method include a hybridization system (manufactured by Nara Machinery Co., Ltd.) to which a high-speed airflow impact method is applied, an ng mill (manufactured by Hosokawa Micron), a mechanomill (manufactured by Okada Seiko), and the like. . However, it is of course not limited to such a method.

The content of the imidazole derivative represented by the general formula [I] should be appropriately selected depending on the type of the toner, the toner additive, the type of the binder resin, and the like, and the developing method (two-component or one-component) of the toner. However, when it is contained in the toner by a pulverization method or a suspension method, the amount is 0.1 to 20 parts by weight, preferably 1 to 10 parts by weight, based on 100 parts by weight of the resin constituting the toner. If the amount is less than 0.1 part by weight, a desired amount of charge cannot be obtained. If the amount is more than 20 parts by weight, the amount of charge becomes unstable, and the fixing property is lowered.

When the imidazole derivative is used by being attached and fixed to the toner surface, 0.001 to 10 parts by weight based on 100 parts by weight of the toner particles.
Parts by weight, preferably 0.05 to 2 parts by weight, more preferably
Use 0.1 to 1 part by weight. If the amount is less than 0.001 part by weight, the amount of the charge control agent present on the surface of the toner particles is small and the charge amount is insufficient.If the amount is more than 10 parts by weight, the charge control agent is not sufficiently attached to the toner surface, and The separation of the charge control agent from the toner surface poses a problem. When the charge control agent is adhered and fixed on the toner surface, a stable charge amount can be imparted by using a very small amount as described above, and the imidazole derivative of the present invention is white. Therefore, it is possible to provide a color toner which is excellent in charging performance and can form a clear color image.

When the imidazole derivative represented by the general formula [I] is contained in the toner, it is used in a particle size of 5 μm or less, preferably 3 μm or less, more preferably 1 μm or less. When used with a particle size larger than 5 μm, the dispersion state becomes non-uniform, and various characteristics of the charge amount become non-uniform. 1 μm when the imidazole derivative is attached to the toner surface
The particle size is more preferably 0.5 μm or less. Use of a particle size larger than 1 μm is disadvantageous in that the toner particles are uniformly adhered and fixed to the toner surface.

The charge control agent imidazole derivative of the present invention may be used in combination with another positive charge control agent. Further, in order to stabilize the charging property, a very small amount of a negative charge control agent may be added. As described above, when the charge control agent of the present invention is used in combination with another charge control agent, the total amount thereof is set to be within the above-mentioned usage range.

As the positive charge control agent, for example, Nigrosine Base EX
(Manufactured by Orient Chemical Industries), quaternary ammonium salt P
-51 (manufactured by Orient Chemical Industries), Nigrosine, Bontron N-01 (manufactured by Orient Chemical Industries), Sudan Chief Schwarz BB (Solvent Black 3: Color Index 26)
150), Fettschwarz HBN (CINo. 26150), Brilliant Spirits Schwarz TN (Falben, manufactured by Fabriken Bayer), Pavbon Schwarz X (Falberge Hoechst), and further alkoxylated amines.
Alkyl amides, molybdate chelate pigments, and the like, and examples of the negative charge control agent include oil black (Color Index 26150), oil black BY (manufactured by Orient Chemical Industries, Ltd.), and Bontron S-22 (Orient Chemical Industries, Ltd.). Salicylic acid metal complex E-81 (manufactured by Orient Chemical Industries), thioindigo pigment, sulfonylamine derivative of copper phthalocyanine, Spiron Black TR
H (manufactured by Hodogaya Chemical), Bontron S-34 (manufactured by Orient Chemical), Nigrosine SO (manufactured by Orient Chemical), Celes Schwarz (R) G (manufactured by Farben Fabriken Bayer), black Mogen Schwarz ET
OO (CINo. 14645), Azo Oil Black (R) (manufactured by National Aniline Co., Ltd.) and the like.

The resin constituting the toner is not particularly limited as long as it is generally used as a binder in a toner. For example, the resin can be obtained by polymerizing the following monomers. Styrene resin,
(Meth) acrylic resin, olefin resin, amide resin, carbonate resin, thermoplastic resin such as polyether, polysulfone, polyester resin, epoxy resin, or urea resin, urethane resin, epoxy resin, etc. Various thermosetting resins and their copolymers and polymer blends are used. As the synthetic resin used in the toner for developing an electrostatic latent image of the present invention, not only those in a perfect polymer state as in a thermoplastic resin, but also oligomers or prepolymers as in a thermosetting resin In addition, those containing a prepolymer, a cross-linking agent and the like partially in the polymer can also be used.

Specific examples of the monomers constituting the resin used in the present invention include the following. That is, as the vinyl monomer, for example, styrene, o-
Methylstyrene, m-methylstyrene, p-methylstyrene, p-ethylstyrene, 2,4-dimethylstyrene,
pn-butylstyrene, p-tert-butylstyrene,
p-n-hexylstyrene, p-n-octylstyrene, p-n-nonylstyrene, p-n-decylstyrene, p-n-dodecylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, 3,4
And styrene such as dichlorostyrene and derivatives thereof, among which styrene is most preferred. Other vinyl monomers, for example, ethylene, propylene, butylene, ethylenically unsaturated monoolefins such as isobutylene, vinyl chloride, vinylidene chloride, vinyl bromide, vinyl halides such as vinyl fluoride, vinyl acetate, Vinyl esters such as vinyl propionate, vinyl benzoate and vinyl butyrate, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, propyl acrylate, n-octyl acrylate,
Dodecyl acrylate, 2-ethylhexyl acrylate,
Stearyl acrylate, 2-chloroethyl acrylate,
Phenyl acrylate, α-methyl methyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, propyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, methacrylic acid 2 (Meth) acrylic acid such as α-methylene aliphatic monocarboxylic esters such as ethylhexyl, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, acrylonitrile, methacrylonitrile, acrylamide and the like Derivatives, vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, vinyl methyl ketone, vinyl hexyl ketone, methyl isopropenyl ke And N-vinyl compounds such as N-vinylpyrrole, N-vinylcarbazole, N-vinylindole and N-vinylpyrrolidone, and vinylnaphthalenes.

In addition, as a monomer for obtaining an amide resin, caprolactam, and further as a dibasic acid, terephthalic acid, isophthalic acid, adipic acid, maleic acid, succinic acid, sebacic acid, thioglycolic acid, and the like can be given, and diamines include , Ethylenediamine, diaminoethyl ether, 1,4-diaminobenzene, 1,4-diaminobutane and the like.

As monomers for obtaining urethane resins, diisocyanates include p-phenylene diisocyanate and p-
Xylene diisocyanate, 1,4-tetramethylene diisocyanate, and the like.Examples of glycols include ethylene glycol, diethylene glycol,
Propylene glycol, polyethylene glycol and the like can be mentioned.

As a monomer for obtaining a urea resin, diisocyanates include p-phenylene diisocyanate, p-xylene diisocyanate, 1,4-tetramethylene diisocyanate, and the like.Diamines include ethylenediamine, diaminoethyl ether, 1,4
-Diaminobenzene, 1,4-diaminobutane and the like.

Examples of the monomers for obtaining the epoxy resin include amines such as ethylamine, butylamine, ethylenediamine, 1,4-diaminobenzene, 1,4-diaminobutane, and monoethanolamine.The diepoxy compounds include diglycidyl. Examples thereof include ether, ethylene glycol diglycidyl ether, bisphenol A diglycidyl ether, and hydroquinone diglycidyl ether.

Further, as a monomer for obtaining a polyester resin, as a polyol component, ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,3-butane Diol, 2,3-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, 2-ethyl-1,3-hexanediol, 2,2,4-trimethyl-1,3-pentane Diol, 1,4-bis (2-hydroxymethyl) cyclohexane, 2,2-bis (4-hydroxypropoxyphenyl)
Propane, bisphenol A, hydrogenated bisphenol A, polyoxyethylenated bisphenol A, etc., and as the polybasic acid component, maleic acid, fumaric acid,
Unsaturated carboxylic acids such as mesaconic acid, citraconic acid, itaconic acid, glutaconic acid, 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, phthalic acid,
Terephthalic acid, isophthalic acid, succinic acid, adipic acid,
Malonic acid, sebacic acid, 1,2,4-cyclohexanetricarboxylic acid, 1,2,5-cyclohexanetricarboxylic acid, 1,
2,4-butanetricarboxylic acid, 1,3-dicarboxy-2-
Saturated carboxylic acids such as methyl-2-methylcarboxypropane and tetra (methylcarboxy) methane and the like, and acid anhydrides and esters with lower alcohols thereof can also be used. Maleic acid, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, tetrachlorophthalic anhydride, tetrabromophthalic anhydride, dimethyl terephthalate, and the like can be given. The polyester resin used in the present invention is not limited to the above-described one obtained by polymerizing the polyol component and the other basic acid component one by one in combination. Particularly, as the polybasic acid component, an unsaturated carboxylic acid and a saturated carboxylic acid, or a combination of a polycarboxylic acid and a polycarboxylic anhydride is often used.

It is desirable to further add a low-molecular-weight polyolefin-based wax to the thermoplastic resin, the amount of which is 1 to 10 parts by weight, preferably 2 to 6 parts by weight, per 100 parts by weight of the thermoplastic resin.
Parts by weight. The compound represented by the general formula [I] of the present invention exhibits good positive charge controllability with respect to these compositions, and can impart practically sufficient chargeability.

In recent years, there has been a demand for a technology capable of copying at higher speeds. For toner used for such high-speed development, the fixability of the toner to transfer paper or the like in a short time and the separating property from the fixing roller are improved. There is a need. Therefore, it is used at the time of high-speed development, and the styrene-based monomer (meth)
The homopolymer or copolymer polymer synthesized from an acrylic monomer, (meth) acrylate, or the above-mentioned polyester resin has a number average molecular weight (Mn), a weight average molecular weight (Mw), a Z average molecular weight (Mn). The relationship with Mz) is 1,000 ≦ Mn ≦ 7,000 40 ≦ Mw / Mn ≦ 70 200 ≦ Mz / Mn ≦ 500, and the number average molecular weight (Mn) is further 2,000 ≦ M
It is preferable to use those where n ≦ 7,000.

Polyester resin has attracted attention as a toner constituent resin because of its PVC resistance, translucency as a translucent color toner, and adhesiveness to OHP sheets. And it is difficult to use as a positively chargeable toner resin. These polyester resins have a glass transition temperature of 55 to 70 ° C. and a softening point of 80 when used for translucent toner.
It is desirable to use a linear polyester at ~ 150 ° C.
When used as an oilless fixing toner, a toner containing a gelling component having a glass transition temperature of 55 to 80 ° C., a softening point of 80 to 150 ° C., and 5 to 20% by weight is desirable. But,
The imidazole derivative represented by the general formula [I] of the present invention shows good positive charge controllability even for such a polyester resin, and can impart practically sufficient chargeability.

The imidazole derivative represented by the general formula [I] of the present invention is a resin mainly composed of a linear urethane-modified polyester (C) obtained by reacting a linear polyester resin (A) with a diisocyanate (B). Practically sufficiently good positive charge controllability can be imparted to the formed toner. The linear urethane-modified polyester referred to here is a linear polyester resin (A) 1 comprising a dicarboxylic acid and a diol, having a number average molecular weight of 1,000 to 20,000, an acid value of 5 or less, and substantially having a terminal group consisting of a hydroxyl group. Per mole,
A linear urethane-modified polyester resin obtained by reacting 0.3 to 0.95 mol of diisocyanate (B) (C)
The resin (C) has a glass transition temperature of 40 to 80 ° C. and an acid value of 5 or less as a main component. As the dicarboxylic acid, diol and diisocyanate, those described above can be used.

As the colorant contained in the toner for developing an electrostatic latent image of the present invention, various kinds of organic and inorganic pigments and dyes as shown below can be used.

That is, examples of black pigments include carbon black, copper oxide, manganese dioxide, aniline black, and activated carbon.

As yellow pigments, yellow lead, zinc yellow, cadmium yellow, yellow iron oxide, mineral fast yellow, nickel titanium yellow, navels yellow, naphthol yellow S, banza yellow G, banza yellow 10G, benzidine yellow G, benzidine yellow GR, There are quinoline yellow lake, permanent yellow NCG, tartrazine lake and so on.

As the orange pigment, red lead, molybdenum orange,
There are Permanent Orange GTR, Pyrazolone Orange, Vulcan Orange, Indaslen Brilliant Orange RK, Benzidine Orange G, and Indaslen Brilliant Orange GK.

Red pigments include red iron, cadmium red, lead red, mercury sulfide, cadmium, permanent red 4R, lithol red, pyrazolone red, watching red, calcium salt, lake red D, brilliant carmine 6B, eosin lake, rhodamine lake B, Alizarin Lake, Brilliant Carmine 3B and others.

Examples of purple pigments include manganese purple, fast violet B, and methyl violet lake.

Examples of the blue pigment include navy blue, cobalt blue, alkali blue lake, Victoria blue lake, phthalocyanine blue, metal-free phthalocyanine blue, partially chlorinated phthalocyanine blue, fast sky blue, and indaslen blue BC.

Green pigments include chrome green, chromium oxide, pigment green B, malachite green lake, final yellow green G, and the like.

Examples of white pigments include zinc white, titanium oxide, antimony white, and zinc sulfide.

The extender includes baryte powder, barium carbonate, clay, silica, white carbon, talc, alumina white and the like.

Various dyes such as basic, acidic, disperse, and direct dyes include nigrosine, methylene blue, rose bengal, quinoline yellow, and ultramarine blue.

These colorants can be used alone or in combination of two or more, with respect to 100 parts by weight of the synthetic resin contained in the core particles and 100 parts by weight of the synthetic resin contained in the outer shell layer, more preferably 1 to 20 parts by weight, more preferably It is desirable to use 2 to 10 parts by weight. That is, when the amount is more than 20 parts by weight, the fixability of the toner is reduced, while when the amount is less than 1 part by weight, a desired image density is not obtained. When used as a translucent color toner, the following colorants are used. Various pigments and dyes of various colors can be used as shown in FIG.

Examples of yellow pigments include CI10316 (Naphthol Yellow S), CI11710 (Hanza Yellow 10G), CI11660 (Hanza Yellow 5G), CI11670 (Banza Yellow 3G), CI1
1680 (Banzaero G), CI11730 (Hanzaero G)
R), CI11735 (Hanzaero A), CI11740 (Hanzaero RN), CI12710 (Hanzaero R), CI127
20 (pigment yellow L), CI21090 (benzidine yellow), CI21095 (benzidine yellow G), CI21100
(Benzidine Yellow GR), CI20040 (Permanent Yellow NCG), CI21220 (Vulcan Fast Yellow 5),
CI21135 (Vulcan Fast Yellow R) and the like.

CI12055 (Stalin I) as a red pigment,
CI12075 (Permanent Orange), CI12175 (Resole Fast Orange 3GL), CI12305 (Permanent Orange GTR), CI11725 (Hanzaero 3R), CI21
165 (Vulcan Fast Orange GG), CI21110 (Benzidine Orange G), CI12120 (Permanent Red 4
R), CI1270 (parared), CI12085 (firered), CI12315 (brilliant fast scarlet), CI12310 (permanent red F2R), CI12
335 (permanent red FRL), CI12440 (permanent red FRL), CI12460 (permanent red FRL)
L), CI12420 (Permanent Red F4RH), CI1245
0 (light fast red toner B), CI12490 (permanent carmine FB), CI15850 (brilliant carmine 6B) and the like.

Examples of the blue pigment include CI74100 (metal-free phthalocyanine blue), CI74160 (phthalocyanine blue), and CI74180 (fast sky blue).

These colorants can be used alone or in combination. It is desirable to use 1 to 10 parts by weight, more preferably 2 to 5 parts by weight, based on 100 parts by weight of the resin contained in the toner particles. That is, if the amount is more than 10 parts by weight, the fixing property and the light transmitting property of the toner are reduced.
If the amount is less than the weight part, a desired image density may not be obtained.

An offset preventing agent may be used in combination with the toner of the present invention to improve fixability. As the anti-offset agent, various waxes, in particular, polyolefin waxes such as low molecular weight polypropylene and polyethylene, or oxidized polypropylene and polyethylene are preferably used. Furthermore, these waxes have a number average molecular weight (Mn) of 1000-
Those having a 20,000 and a softening point (Tm) of 80 to 150 ° C are preferred. If the number average molecular weight Mn is 1000 or less, or the softening point Tm is 80 ° C or less, uniform dispersion with the synthetic resin component in the synthetic resin coating layer cannot be performed, only the wax is eluted on the toner surface, and toner storage or This may not only result in undesired results at the time of development, but also cause contamination of a tourist object such as filming. On the other hand, if the number average molecular weight exceeds 20,000 or the Tm exceeds 150 ° C., not only the compatibility with the resin deteriorates but also the effect of containing a wax such as high-temperature offset resistance cannot be obtained. Also,
A wax having a polar group is desirable in terms of compatibility.

A fluidizing agent may be added to and mixed with the toner of the present invention in order to improve fluidity. Examples of the fluidizing agent include silica, aluminum oxide, titanium oxide, a mixture of silica and aluminum oxide, and a mixture of silica and titanium oxide. These substances may be added internally.

The toner of the present invention can be applied to both two-component developers and one-component developers (magnetic and non-magnetic). When used as a two-component developer, carrier powder such as ferrite carrier, coating carrier, iron powder carrier
A known carrier such as a carrier having a composite charged surface can be used.

To prepare the toner for developing an electrostatic image according to the present invention, the charge control agent according to the present invention is made of a thermoplastic resin and a pigment or dye as a colorant, and if necessary, a magnetic material, and other additives are ball milled. After thoroughly mixing with another mixer, the mixture is melted, mixed and kneaded using a heat kneader such as a heating roll or kneader to disperse or disperse the pigment or dye while the resins are mutually compatible, and then cooled and solidified. Subsequent pulverization and classification can provide a toner having a desired average particle size.

Alternatively, a method in which the material is dispersed in a binder resin solution and then obtained by spray drying, or a method in which a predetermined material is mixed with a monomer to constitute the binder resin to form a suspension and then polymerized. A polymerization method of obtaining a toner, a method of producing a toner, a method of including a core material and / or a shell material in a so-called microcapsule toner comprising a core material and a shell material, and the like can be applied.

Further, the method can also be effectively used in a method in which a charge control agent is attached to the surface layer by the action of van der Waals force and electrostatic force, and then fixed by mechanical impact force or the like.

The toners produced by these methods can be used for development for visualizing an electrostatic image in electrophotography, electrostatic recording, electrostatic printing, and the like by conventionally known means.

[Example 1] (Toner A) component parts by weight styrene-n-butyl 100 methacrylate resin (softening point 132 ° C, glass transition point 60)
℃) Carbon black 8 (manufactured by Mitsubishi Kasei Co., Ltd .: MA # 8) Viscol 550P (manufactured by Sanyo Chemical Industry Co., Ltd.) The above materials were sufficiently mixed by a ball mill, and kneaded on three rolls heated to 140 ° C. After cooling the kneaded material,
Coarse pulverization was performed using a feather mill, and fine pulverization was performed using a jet mill. Thereafter, air classification was performed to obtain a fine powder having an average particle diameter of 10 μm. The particles obtained here are referred to as (i).

Further, with respect to 100 parts by weight of the obtained fine particles, 0.3 part by weight of the compound (2) as a charge control agent was put into a Henschel mixer, and mixed and stirred at 1,500 rpm for 2 minutes to obtain a surface of the colorant-containing resin particles. The compound (2) microparticles were electrostatically attached to Van der Vaalska.
Next, Nara Machine Hybridization System NHS-1
Using a mold at 6000 rpm for 3 minutes, the compound (2) was fixed on the surface of the colorant-containing resin particles to obtain a toner A.

[Example 2] (Toner B) Component Parts by weight Polyester resin 100 (manufactured by Kao Corporation: Tuftone NE-382) Brilliant Carmine 6B 3 (CI15850) Compound (4) 4 After the above materials were thoroughly mixed in a ball mill, 140 ° C. And kneaded on a heated three-roll mill. After cooling the kneaded material,
Coarse pulverization was performed using a feather mill, and fine pulverization was performed using a jet mill. Thereafter, air classification was performed to obtain a fine powder having an average particle size of 11 μm.

 The resulting fine powder is referred to as toner B.

[Example 3] (Toner C) Component weight part polyester resin 100 (manufactured by Kao Corporation: NE-1110) Carbon black 8 (manufactured by Mitsubishi Kasei Industries: MA # 8) Low molecular weight oxidized polypropylene 3 Viscol TS-200 ( Compound (7) 5 Compound 11 (average particle size 11 μm) in the same manner as in Example 2 (Toner B)
Was obtained. The obtained fine powder is referred to as a toner C.

[Example 4] (Toner D) Component weight part polyester resin 100 (manufactured by Kao Corporation: NE-382) Phthalocyanine pigment 3 In the same manner as in Example 2, colorant-containing resin particles having an average particle diameter of 8 µm were obtained.

Further, with respect to 100 parts by weight of the obtained fine particles, 0.3 part by weight of a compound (9) as a charge control agent was put into a Henschel mixer, and mixed and stirred at 1,500 rpm for 2 minutes to obtain a surface of the colorant-containing resin particles. The microparticles of compound (9) were electrostatically attached to Van der Vaalska.
Next, Nara Machine Hybridization System NHS-1
Using a mold at 6000 rpm for 3 minutes, the compound (9) was fixed on the surface of the colorant-containing resin particles to obtain a toner D.

Example 5 (Toner E) Monodisperse spherical copolymer of styrene and n-butyl methacrylate obtained by a seed polymerization method (average particle size: 6 μm: glass transition temperature: 54 ° C .: softening point: 128 ° C., gelling component) 100 parts by weight (containing 15% of toluene-insoluble component) and 8 parts by weight of carbon black (MA # 8, manufactured by Mitsubishi Kasei Kogyo Co., Ltd.)
In a Henschel mixer, the mixture was mixed and stirred at 1500 rpm for 2 minutes to deposit carbon black on the surface of the polymer particles. Next, a carbon black was immobilized on the surface of the polymer particles by performing a treatment at 6,000 rpm for 3 minutes using Nara Machine Hybridization System NHS-1.

Polymer particles treated with the above carbon black
100 parts by weight and 10 parts by weight of MMA / iBMA (1: 9) particles MP-4951 (manufactured by Soken Chemical Co., Ltd .: average particle size: 0.2 μm; glass transition temperature: 85 ° C.) A resin coat layer was provided by the same treatment as described above except that the time was set to be minutes. Further, based on 100 parts by weight of the obtained polymer particles, the positive charge control agent compound (14)
0.5 parts by weight of the fine particles of the above were fixed to the surface of the fine particle toner of the compound (14) by performing the same treatment as described above in which the carbon black layer was formed, the average particle diameter was 6.5 μm, the sphericity was 132, and the variation coefficient was 8%. Was obtained.

[Comparative Example 1] (Toner F) The same procedure as in Example 3 (Toner C) was carried out except that Compound (7) was used as the charge control agent and Nigrosine-based Bontron N-01 (manufactured by Orient Chemical Industries) was changed to 5 parts by weight. Fine particles having an average particle size of 11 μm were obtained by the method. The obtained fine particles are referred to as a toner F.

[Comparative Example 2] (Toner G) An average particle diameter of 11 µm was obtained in the same manner as in Example 3 (Toner C) except that the 2-aminobenzimidazole compound was changed to 5 parts by weight instead of compound (7) as the charge control agent. Particles were obtained. The fine particles obtained here are referred to as toner G.

[Example 6] (toner H) component by weight , thermoplastic styrene acrylic resin 100 Mn: 4,200 Mw: 210,900 Mz: 1,323,000 Mw / Mn: 50.2 Mz / Mn: 315 Tg: 62 ° C Softening point: 115 ° C Acid value: 25.8 ・ Carbon black 8 (manufactured by Mitsubishi Kasei Kogyo Co., Ltd .: MA # 8) ・ Low molecular weight polypropylene 4 (manufactured by Sanyo Kasei Kogyo Co., Ltd .: Viscol 605P) ・ Compound (7) 3 Averaged in the same manner as in Example 2 (Toner B) Particle size 11μm
Was obtained. The fine powder obtained here is referred to as toner H.

Example 7 (Toner I) 100 parts by weight of component : thermoplastic polyester resin 100 Mn: 3,400 Mw: 213,400 Mz: 1,183,200 Mw / Mn: 62.8 Mz / Mn: 348 Acid value: 16.7 Softening point: 109 ° C. Tg: 64 ° C. -Lake Red C5 (manufactured by Dainichi Seika Kogyo Co., Ltd.)-Low molecular weight oxidized polypropylene 5 (manufactured by Sanyo Chemical Industry Co., Ltd .: Viscol TS-200)-Compound (4) 3 In the same manner as in Example 2 (Toner B) Average particle size 11μm
Was obtained. The fine powder obtained here is referred to as toner I.

[Example 8] (toner J) component parts by weight : linear urethane-modified polyester resin 100 Mn: 4,000 Mw: 35,400 Mw / Mn: 8.9 Tg: 56 ° C Acid value: 0.8 Copper phthalocyanine 5 (manufactured by Dainichi Seika Kogyo Co., Ltd.)・ Low molecular weight polypropylene 4 (Viscol 605P, manufactured by Sanyo Chemical Industries, Ltd.) ・ Compound (4) 3 Average particle size 11 μm in the same manner as in Example 2 (Toner B)
Was obtained. The fine powder obtained here is referred to as toner J.

Comparative Example 3 A partial powder having an average particle diameter of 11 μm was obtained in the same manner as in Example 7, except that 3 parts by weight of Nigrosine Base EX (manufactured by Orient Chemical Industries) was used instead of the compound of the present invention. The fine powder obtained here is referred to as a toner (K).

Comparative Example 4 A partial powder having an average particle size of 11 μm was obtained in the same manner as in Example 8, except that the compound of the present invention was replaced with 5 parts by weight of a quaternary ammonium salt P-51 (manufactured by Orient Chemical Industries). . The fine powder obtained here is referred to as a toner (L).

[Example 9] Ingredients by weight : polyester resin 100 Mn: 3,400 Mw: 213,400 Mz: 1,183,200 Mw / Mn: 62.8 Mz / Mn: 348 Acid value: 16.7 Softening point: 109 ° C Tg: 64 ° C ・ Oxidized low molecular weight polypropylene 5 (Viscosity at 160 ° C 140
cps acid value 5) Carbon black MA # 88 (manufactured by Mitsubishi Kasei Kogyo Co., Ltd.) Particles of the above material having an average particle diameter of 10.2 μm were obtained in the same manner as in the preparation of particles (i).

Further, with respect to 100 parts by weight of the obtained fine particles, 0.3 part by weight of the compound (8) as a charge control agent was put into a Henschel mixer, and mixed and stirred at a rotation speed of 1,500 rpm for 2 minutes. The microparticles of compound (8) were vandalfarska and electrostatically attached to the sample.
Next, Nara Machine Hybridization System NHS-1
The compound (8) was fixed to the surface of the colorant-containing resin particles by performing a treatment at 6000 rpm for 3 minutes using a mold to obtain a toner M.

[Comparative Example 5] In Example 9, the nigrosine dye Bontron N- was used in place of the compound (8) as the charge control agent for treating the particle surface.
01 (manufactured by Orient Chemical Industry Co., Ltd.) A toner N having an average particle size of 11 μm was obtained by the same composition and method except that the amount was 0.3 parts by weight.

[Example 10] As in Example 4, 100 parts by weight of colorant-containing resin particles having an average particle diameter of 8 µm and MMA / iBMA (1: 9) particles MP-4951 (manufactured by Soken Kagaku Co., Ltd .; average particle diameter of 0.2 µm, glass) (Transition point 85 ° C.) 15 parts by weight, and 1 part by weight of the compound (10) according to the present invention are further placed in a Nara Machine OM dicer and mixed and stirred at 1200 rpm for 2 minutes.
Using a S-1 type, a treatment is performed at 8,000 rpm for 5 minutes to provide a resin coat layer containing the charge control agent compound (10).

Example 11 and Example 12 The thermoplastic resin used in Example 6 was replaced with Example 11
In, thermoplastic styrene-acrylic resin Mn: 12,800 Mw: 178,900 Mz: 957,600 Mw / Mn: 14.0 Mz / Mn: 75 Acid value: 62.3 Softening point: 127 ° C In Example 12, thermoplastic styrene-acrylic resin Mn: 4,800 Mw: 374,400 Mz: 3,321,600 Mw / Mn: 78 Mz / Mn: 692 Acid value: 66.2 Softening point: Toner P and toner each having an average particle size of 11 μm by the same composition and manufacturing method except that the temperature is changed to 138 ° C. Q was obtained.

[Manufacture of Carrier] In order to use the toner for evaluation described below, a binder-type carrier was manufactured as follows. Ingredients by weight・ Polyester resin 100 (manufactured by Kao Corporation: NE-1110) ・ Inorganic magnetic powder 500 (manufactured by Toda Kogyo, EPT-1000) ・ Carbon black 2 (manufactured by Mitsubishi Kasei Corporation, MA # 8) And then pulverized, and then melted and kneaded using an extruder kneader set at 180 ° C. in the cylinder section and 170 ° C. in the cylinder head section. After cooling, the kneaded product was finely pulverized with a jet mill, and then classified using a classifier to obtain a magnetic carrier having an average particle size of 55 μm.

[Measurement of Particle Size] The particle sizes of the toner and the carrier were measured as follows.

(1) Carrier particle size Carrier particle size is microtrack model 7995-10SR
A (measured using Nikkiso Co., Ltd., and the average particle size was determined.

(2) Toner Particle Size The toner average particle size was measured by using a Coulter Counter II (manufactured by Coulter Counter Co.) and measuring the relative weight distribution by particle size using a 100 μm aperture tube.

Evaluation method for various properties Examples 1 to 12 and Comparative Example 1 thus obtained
Various characteristics were evaluated for the toners A to Q of Nos. 1 to 5 as described below. The amount of colloidal silica R-972 (manufactured by Nippon Aerosil Co., Ltd.): 0.1 with respect to 100 parts by weight of each toner.
Post-processing was performed in parts by weight and used for evaluating various properties.

Charge amount (Q / M) and scattering amount 2 g of the surface-treated toner and the carrier 28
In order to check the rise of the charge amount of the toner when put in a plastic bottle of g and 50 cc and put on a rotating frame and rotated at 1200 rpm, the charge amount after stirring for 10 minutes was measured, and the scattering amount at that time was also examined . Similarly, the toner and the carrier were put in a plastic bottle, and the amount of charge and the amount of scattering after storage at 35 ° C. and a relative humidity of 85% for 24 hours were measured to examine the moisture resistance.

The scattering amount was measured with a digital dust meter P5H2 type (manufactured by Shibata Chemical Co., Ltd.). The dust meter and magnet roll are
cm, and after setting 2 g of developer on this magnet roll, when the magnet is rotated at 2000 rpm, the dust meter reads the toner particles that are generated as dust and counts for 1 minute. Display in a few cpm.
A three-step evaluation was performed, in which the obtained scattering amount was 300 cpm or less, 以下, 500 cpm or less, Δ, and when it was more than 500 cpm, x. Although it can be practically used at the rank of Δ or higher, ○ is desirable. Table 1 shows the measurement results of the charge amount and the scattering amount.

Evaluation of Image Deposition The predetermined toner shown in Table 1 and the above carrier were
Carrier was mixed at a ratio of 7/93 to prepare a two-component developer. Using this developer, Examples 1 to 12 and Comparative Examples 1 to 5
The various image evaluations shown in Table 1 were performed using EP-470Z (system speed: 18 cm / sec; manufactured by Minolta Camera Co., Ltd.) (however, EP-470Z was used for Examples 2, 4 and 10).
(A fixing device manufactured by Minolta Camera Co., Ltd.) modified to an oil application method was used.)

1) Fogging on Image In the combination of various toners and carriers as described above, image formation was performed using the above copying machine. For the fog on the image, evaluate the toner fog on the white background image,
The ranking was performed. Although it can be practically used at the rank of Δ or higher, it is preferable that the rank is at least ○.

2) Printing durability test A printing durability test of 100,000 sheets was performed using a chart having a B / W ratio of 6%, and the image and fog were evaluated. The results are shown in Table 1. In the table, ○ means a practically usable area, and × means a practically problematic area.

3) Translucency In Examples 2, 4 and 10, a translucency test was also performed.

The translucency was visually evaluated for the color vividness of the projected image when the fixed image on the OHP sheet was projected by the OHP projector. The results are shown in Table 1. In the table, ○ means a practically usable area in terms of color reproduction.

Moisture resistance test Use EP-470Z equipment for high humidity of 85% (relative humidity) at 35 ℃.
After storage for a time, the image evaluation, the charge amount and the scattering amount were measured.

The results are shown in Table 1. The symbols in the table have the same meanings as described in the above evaluations.

High-speed fixability High-speed fixability of Examples 6, 7, 9, 11, and 12 was evaluated as follows.

The temperature at which high-temperature offset and low-temperature offset occur when a 60 Φ fixing roller coated with a Teflon-based resin and a fixing device pressed under pressure by applying an LTV rubber roller under pressure of 100 kg and fixing the toner at a speed of 45 cm / sec. The fixing strength of ID1.2 and ID0.6 when fixing was performed at 175 ° C. was determined.

High-temperature offset is a phenomenon in which the toner in contact with the hot roll is melted and softened, and the toner attached to the roller is transferred to copy paper in the second rotation. On the other hand, low-temperature offset is a phenomenon in which the toner is not sufficiently melted by the hot roll Since only the surface melted,
This is a phenomenon in which the toner adhering to the heat roll with little fixation to paper is transferred to copy paper at the second rotation.

 The ID is a figure value of the image density measured by a Sakura reflection densitometer.

80% or more is required for ID1.2 and 70% or more for ID0.6.

For fixing strength, the copied image is rubbed with a device having a characteristic of applying a load of 1 kg on sand poppy rubber to erase the toner image.
At this time, the ratio of the reflection temperature before and after rubbing with
Expressed as 0 fraction.

 In the above evaluation, those in the practically usable area were indicated by ○, and those that could not be used were indicated by ×.

Effects of the Invention The toner containing the imidazole derivative of the present invention exhibits a stable and uniform charge amount, and does not cause toner aggregation, fogging on an image, toner scattering, etc. even when used continuously for a long time.

By using the imidazole derivative of the present invention, a toner composed of a negatively chargeable resin can be used in a positively charged state without impairing the above effects.

According to the present invention, it is possible to obtain a color toner which maintains the above characteristics and is excellent in color reproducibility or translucency.

The imidazole derivative of the present invention can be applied to a toner for high-speed development.

Claims (1)

(57) [Claims] 1. A compound represented by the following general formula [I]: [Wherein R ₁ , R ₂ and R ₃ represent a hydrogen atom, an alkyl group, an aralkyl group or an aryl group, which may be the same or different. n represents an integer of 1 or more. ] The toner for electrostatic charge development characterized by containing the imidazole derivative represented by these.