JP2850012B2 - Color toner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a color toner used in color electrophotography, which is particularly excellent in light resistance, high in color saturation, good in charge stability, and A magenta toner having improved offset resistance.

[Prior Art] Magenta toner for color electrophotography requires, as a colorant, 1) excellent spectral reflection characteristics (color characteristics), a clear magenta color, and 2) good dispersibility in resin and high coloring. Having high power and high image density,
3) Excellent stability to light, that is, good light fastness of the copy, 4) Matching to the function required of the copying machine and not giving a significant side effect, for example, charging characteristics which affect development characteristics And adhesion to the fixing roller surface and dyeability.

Conventional magenta colorants for color electrophotography include quinacridone pigments, thioindigo pigments, xanthene dyes, anthraquinone dyes, and azo dyes.

For example, JP-B-49-46951 describes 2,9-dimethylquinacridone pigments, JP-A-55-26574 relates to thioindigo pigments, and JP-A-59-57256 discloses xanthene dyes. There is a description about. JP-B-55-42383 describes an anthraquinone dye. Further, in Japanese Patent Publication No. 53-47174, the present applicant has proposed a magenta toner in combination with a suitable coloring resin using a quinacridone-based or rhodamine-based coloring agent. However, none of the colorants satisfies all of the characteristics 1) to 4), and each has a strength and a disadvantage.

For example, a quinacridone-based organic pigment is a high-grade pigment having a slightly reddish color and excellent in light resistance, but does not have sufficient performance as a magenta color when added alone. That is, with respect to the hue, the reflection in the bluish portion is less than the ideal magenta color, and the hue is reddish. In addition, since it is a pigment, it has disadvantages such as insufficient dispersion in a colored resin, poor chroma and poor vividness with respect to sharpness. When used alone, the quality of the color reproducibility is insufficient. However, when it is used as a toner, it has preferable characteristics in that carrier contamination due to repeated copying is small.

Therefore, it is very difficult to rely on a single dye or pigment as a magenta colorant, and to make up for the disadvantages of each colorant,
It is realistic to use two or more colorants in combination.

For example, the present applicants have proposed a magenta toner using two oil-soluble dyes as disclosed in JP-A-57-130044 and JP-A-57-130046. This magenta toner has a vivid color tone and excellent saturation, but on the other hand, one of the dyes contains a component that contaminates the silicone rubber used in the heating roller fixing device, so that it is gradually copied by continuous copying. The fixing silicon roller is dyed, and finally, a so-called offset phenomenon in which the toner is fused to the heating roller is caused. Also, the combination of these oil-soluble dyes is effective in reducing the toner charge rather than increasing it. Therefore, charge under low temperature and low humidity
Up can be sufficiently prevented, and a preferable image density can be guaranteed. However, conversely, the toner scatters due to insufficient charging under high temperature and high humidity, thereby contaminating the inside of the apparatus, and fogging due to the low-charged toner tends to cause image contamination.

 The above is summarized as follows.

The use of a pigment-based colorant has advantages such as light resistance and carrier contamination, but the color tone is poorly dispersed in the binder resin,
Inferior in saturation. Conversely, when a dye-based colorant is used, a toner having good dispersion and excellent color tone and saturation can be obtained, but has disadvantages such as poor light resistance and poor contamination of the fixing roller.

Therefore, an attempt has been made to use a pigment-based colorant and a dye-based colorant in combination to make use of the advantages while compensating for these disadvantages.

For example, the present applicant has disclosed a method of improving the dispersion of a pigment in a binder resin by treating the pigment with an oil-soluble dye in JP-A-60-192957. By this method, the hue is vivid, and a good image can be obtained even in an environment such as high temperature and high humidity and low temperature and low humidity.

However, the fixability is not yet sufficient.

In addition, although the purpose is different, JP-A-59-100453 discloses that an oil-soluble dye is used as a conductivity-imparting agent for a toner containing an organic pigment containing a polyester resin as a binder resin in order to prevent fogging and edge effects. A method is disclosed. In this method, fogging and edge effects are suppressed due to the conductivity-imparting effect of the oil-soluble dye, but two or more colors are mixed as a color toner to form a toner of another color, or toner of two or more colors is superimposed. In addition, when the toner is fixed on a fixing support, the dispersion of the pigment is not sufficient, so that an image having poor chroma and light transmittance is obtained.

Japanese Patent Application Laid-Open No. Sho 60-66261 discloses a method using a chromatic color pigment and at least one chromatic dye soluble in an organic solvent for a functional color toner. However, in this method, a toner having a high concealment ratio can be obtained.
Light transmission is inferior.

In addition, the applicant of the present invention disclosed in Japanese Patent Application Laid-Open No. Sho 62-15555-7 discloses that a coloring agent is used in combination with a rhodamine-based basic dye and a pigment, and that no dyeing offset to a silicon rubber roller occurs. showed that.

However, in this method, sufficient dispersion of the colorant cannot be obtained, and the colorant tends to aggregate. In particular, the toner adheres to the periphery of the carrier during development, and the carrier is developed together with the toner. "Development called" is likely to occur.

Further, the present applicant has disclosed a method of obtaining a color toner by treating a basic dye with a resin having an acid value of 5 to 120 in JP-A-54-5733. In this method, since the basic dye forms a kind of resin salt, it is possible to obtain a color toner having excellent spectral reflection characteristics and transparency, as well as stable fluidity and triboelectric charging characteristics. However, this method is also inferior in light fastness because only the dye is used, and the image after fading is almost reddish.

Further, in order to improve the dispersion of the pigment, and to obtain a toner having excellent color reproducibility and charging characteristics, Japanese Patent Application Laid-Open No.
No. 0755 discloses a method using a polyester resin as a binder resin and using a pigment treated with a polyester resin having a higher molecular weight than the binder resin. In this method, compared to the conventional pigment-only type, the dispersion of the pigment and the other, the charging characteristics and the like can be considerably improved.However, when the dye-based colorant is used as described above, In comparison, the color tone and saturation are slightly inferior.

JP-A-62-30259 discloses a method of preparing a masterbatch containing a pigment, a dye, a charge control agent, and an offset inhibitor, and diluting the masterbatch.

However, even in this method, the dispersion of the colorant is improved, but the fixability of the toner is not drastically improved.

Also, many improvements in binder resins have been reported for the purpose of improving fixability. For example, JP-A-59-226358, 61-126
No. 562 discloses a molecular weight of 10 ^{3 to} 5 × 1 measured by GPC.
0 ^4, and the color toner is proposed which contains a polymer or copolymer of a vinyl monomer having at least one maximum respectively ^{105 to 106} two regions of.

However, when a polymer having a local maximum in the range of 10 ⁵ to 10 ⁶ is contained in about 70 wt%, the high-temperature offset resistance is certainly improved. Poorly, the resulting image will have poor dull saturation.

Further, the present applicant has proposed in Japanese Patent Publication No. 53-23084 that oligostyrene having a molecular weight of 1,000 or less and polystyrene having a molecular weight of tens of thousands or more are used as a binder resin. Although the fixability is improved, the fixability is still not sufficient when used for full-color toner, especially when the amount of toner that produces black color by overlapping three color toners is large. .

That is, there is no magenta toner having excellent light fastness, high chroma, good charge stability, and excellent offset resistance as a color toner at present.

[Problems to be Solved by the Invention] Accordingly, an object of the present invention is to provide a magenta toner that has solved the above-mentioned problems.

That is, an object of the present invention is to provide a magenta toner that can obtain a clear color, has a large coloring power, and is excellent in light fastness.

Still another object is to provide a magenta toner having a wide fixing area without causing deterioration of a fixing roller or the like during fixing.

Another object of the present invention is to provide a magenta toner capable of forming a smooth fixing surface so that the fixed toner does not hinder color reproduction that is irregularly reflected with respect to light.

Still another object is to provide a magenta toner which is excellent in environmental stability, does not cause a change in charging due to a stained color, and can always be stably charged.

[Means and Actions for Solving the Problems] The present invention relates to a color toner containing at least a styrene resin as a binder resin and containing a phenol resin, a quinacridone pigment and an oil-soluble xanthene dye, In the molecular weight distribution by GPC, the proportion of the area A having a molecular weight of less than 10,000 is 55 to 80%, the proportion of the area B having a molecular weight of 10,000 to 50,000 is 5 to 25%, and 5-20
%.

Further, the styrene resin is preferably a styrene copolymer obtained by copolymerizing a styrene monomer with at least one monomer selected from the group consisting of acrylic acids and methacrylic acids.

 This achieves the above-mentioned object.

When thinking about full color toners, the most important thing is
Color reproducibility. In particular, the cyan toner, the magenta toner, and the yellow toner melt at the time of fixing, and a color is produced by mixing colors. Therefore, the viscosity must be reduced in a short time at the time of melting. However, the second important point of practicality is that the problems of fusing temperature, offset, and wrapping, especially regarding fusing, must be satisfied at the same time as color mixing, which is generally contradictory. Things.

However, as a result of diligent studies, the present inventor has satisfied these to some extent at the same time by adjusting the molecular weight distribution of the binder resin, the glass transition point, and the presence of the phenol resin in the main binder resin. It has been found that a toner for use can be obtained.

In other words, in the molecular weight distribution by gel permeation (GPC), components less than 10,000 are related to the color mixing property and flatness of the fixing surface which are most important especially for full-color toner, and components of 10,000 to 50,000 are particularly dependent on the fixing temperature. Related,
Components exceeding 50,000 are particularly concerned with offset resistance, anti-cracking resistance, colorant dispersibility, developability, durability and the like.

If the amount of the component less than 10,000 is less than 55%, the color mixing property and the flatness of the fixing surface tend to be poor, and if it is more than 80%, the offset resistance, the dispersibility of the colorant and the developability tend to be poor. On the other hand, if the proportion of the component of 10,000 to 50,000 is less than 5%, the dispersibility of the colorant becomes poor, and
If it is more than%, problems such as fixability may occur. If the amount of the component exceeding 50,000 is less than 5%, problems such as offset resistance, anti-cracking property, dispersibility of the colorant, developability, durability, and halftone reproducibility are caused. It tends to be worse. If it is more than 20%, problems such as fixing property, color mixing property, and flatness of the fixing surface are caused.

Further, if the Tg of each component in each range is lower than 50 ° C., blocking occurs, which is problematic. If Tg _A is higher than 70 ° C, fixing properties, color mixing properties, and flatness of the fixing surface become problems.If Tg _{B + C} is higher than 65 ° C, fixing properties, color mixing properties, and flatness of the fixing surface become problems. Come.

Further, it is preferable that the polymer is composed of a monomer having a small number of —COOH groups and —OH groups. In other words, if the developing property is slightly changed due to durability and environmental changes, in the case of full color, a change in color appears in the image, so that it is preferable that the number of -COOH groups and -OH groups which are easily influenced by the environment is small.

For the above reasons, the acid value of the polymer is preferably 90 or less, more preferably 50 or less.

Further, a styrene-acrylic copolymer whose polymer is mainly composed of a styrene-based monomer can be easily and stably charged positively or negatively by a charge control agent. On the contrary, it is particularly important that, since the polymer has little polarity, it is difficult to disperse the dye / pigment for color toner. However, if the molecular weight distribution of the present invention is used, sufficient dispersibility can be obtained. I found something. This is especially true when the proportion of the molecular weight distribution of more than 50,000 and less than 10,000 is 1: 7.5.
~ 2: 5.5. That is,
The dispersibility is improved at an appropriate ratio of 50,000 or more, which is a component that is required to be sheared during heat kneading, and 10,000 or less, which has good wettability.

Further, in the present invention, the quinacridone pigment, the xanthene dye and the phenol resin are used for the following reasons.

As described above, if the colorant is a dye alone, dyeing offset to the fixing roller is likely to occur. Since the polarity of the dye / pigment combination system is the same, sufficient dispersion cannot be obtained in a styrene-acrylic binder resin generally used for toner. In addition, the pigment alone has good light fastness, but produces an image with poor chroma and poor color. The inventor has obtained the following findings as a result of intensive studies.

Xanthene oil-soluble dyes have a poor affinity for non-polar organic substances having an aromatic ring, have strong dyeing power for oils, rubbers, and metal oxides, and have low alcohol, ethers, and ketones. Well soluble in molecular esters. For this reason, iron oxide powder, magnetite, and the like are contained in a toner binder containing a non-polar aromatic ring (introducing an aromatic ring can impart the robustness as an electrophotographic toner).
Ferrite, a developer carrier made of a magnetic alloy, or a sleeve carrying the developer, a silicone rubber used for a fixing device, a silicone oil used as a release agent at a high temperature, etc. Xanthene-based oil-soluble dyes that cause the toner to scatter, fog, and reverse when extremely high charge build-up at high humidity occurs Is extracted, transferred, stains the surroundings, and causes a phenomenon in which the magenta color in the image blurs or fades.

Here, when the phenolic resin having polarity coexists with the xanthene dye, the above-mentioned pollution phenomenon can be significantly prevented.

This is presumably because the xanthene dye does not completely dissolve into the phenolic resin, but the phenolic resin has an effect of suppressing the dye from moving in the main binder resin.

This makes it possible to obtain an image with good light fastness due to the pigment and high color saturation with the dye, and to prevent migration of the dye with the phenol resin.

The resin composition in the toner of the present invention includes styrenes,
Those obtained by polymerizing one or more monomers selected from acrylic acids, methacrylic acids and derivatives thereof are preferable from the viewpoint of developing characteristics and charging characteristics. Examples of monomers that can be used include styrenes such as styrene, α-methylstyrene, vinyltriene, and chlorostyrene. Examples of acrylic acids, methacrylic acids and derivatives thereof include acrylic acid, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, n-tetradecyl acrylate, and n-acrylic acid. Hexadecyl, lauryl acrylate, cyclohexyl acrylate,
Acrylates such as diethylaminoethyl acrylate and dimethylaminoethyl acrylate;
Similarly, methacrylic acid, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, amyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, octyl methacrylate,
Methacryls such as decyl methacrylate, dodecyl methacrylate, lauryl methacrylate, diclohexyl methacrylate, phenyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, dimethylaminoethyl methacrylate, glycidyl methacrylate, stearyl methacrylate Acid esters. In addition to the above-mentioned monomers, a small amount of other monomers within a range that can achieve the object of the present invention, such as acrylonitrile, 2-vinylpyridine, 4-vinylpyridine, vinylcarbazole, vinylmethylether, butadiene, isoprene, maleic anhydride, Maleic acid, maleic acid monoesters, maleic acid diesters, vinyl acetate and the like may be used.

As the crosslinking agent used in the toner of the present invention for adjusting the molecular weight distribution, divinyl benzene, bis (4-acryloxypolyethoxyphenyl) propane, ethylene glycol diacrylate, 1,3
-Butylene glycol diacrylate, 1,4-butanediol diacrylate, 1,5-pentanediol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, tetra Ethylene glycol diacrylate, polyethylene glycol # 200, # 400, and # 600 diacrylates, dipropylene glycol diacrylate, polypropylene glycol diacrylate, polyester type diacrylate (MANDA Nippon Kayaku), and the above acrylates as methacrylates One.

Pentaerythritol triacrylate, trimethylolethane triacrylate, trimethylolpropane triacrylate, tetramethylolmethanetetraacrylate, oligoester acrylate and its methacrylate, 2,2-bis (4-methacryloxy, polyethoxyphenyl) as polyfunctional crosslinking agents Examples thereof include propane, diallyl phthalate, triallyl cyanurate, triallyl asocyanurate, triallyl isocyanurate, triallyl trimellitate, and diarylchlorendate.

As a method for producing the resin, a known method is used.
As the polymerization method, a solution polymerization, a suspension polymerization, a bulk polymerization method, or the like is used, and the polymer of the present invention can be obtained by combining two or more resins.

The mixing of two or more resins may be performed in a heat-kneading step in the production of the toner, but the resins may be mixed in a hot-melt state or dissolved and mixed in advance using a solvent. However, a preferred method of polymerizing the first resin in solution and polymerizing it by dissolving the initiator or the like with the monomer of the second resin before removing the solvent is to obtain the polymer of the present invention. This is because two kinds of resins can be dispersed at a molecular level. When a polymer is prepared by this method, either the low molecular weight component or the high molecular weight component may be prepared first.

Furthermore, in such a two-stage polymerization method, not only a combination of solution polymerization and solution polymerization but also any combination of polymerization methods can be used. good.

Examples of the phenolic resin used in the present invention include phenols, cresols, xylenols, catechols, naphthols, alkylphenols, paraphenylphenols, and phenolic hydroxyl groups, and aldehydes or aldehydes such as formaldehyde, acetaldehyde, paraformaldehyde, hexamethylenetetramine, and furfural. Polycondensation polymers between the phenolic hydroxyl group and an alkyl-condensed polymer, which are called oil-soluble phenols, have high thermal stability. It is advantageous.

As a typical example of the quinacridone pigment used in the present invention, and so on. Above all, 5.CIPigment Red 122 is bright,
Since the color saturation is high, it is particularly suitable as a magenta colorant.

The xanthene-based dye used in the present invention is often used as a basic dye, but the basic dye has a large decrease in charging ability under high humidity, and is free of a salt or free base or acid. It is better to make it in a state, and it is good that a dye classified as an oil-soluble dye has good wettability to a resin and improves dispersibility.

As a xanthene-based oil-soluble dye, CI 45170: 1
(CISolvent Red 49), CI45185, CI45190: 1 (CI
Solvent Violet 10), CI45195, CI45350: 1 (CISol
vent Yellow 94), CI45365 (CISolvent Orange 3)
2), CI45366 (CISolvent Red 42), CI45370: 1
(CISolvent Red 72), CI45371 (CISolvent Oran
ge 18), CI45380: 2 (CISolvent Red 43), CI4538
5 (CISolvent Red 44), CI45386 (CISolvent Red
45), CI45395, CI45396 (CISolvent Orange 1
6), CI45410: 1 (CISolvent Red 48), CI45415, C.
I.45425: 1 (CISolvent Red 73), CI45430 (CISolvent Red 73)
vent Red 140), CI45435: 1 (CISolvent Red 47),
CI45440: 1 (CISolvent Red 141), CI45456 (CI
Solvent Orange 17), CI45457 (CISolvent Red 4
6), CI45550 (CISolvent Green 4) and the like. Among them, CISolvent Re is a combination that can express magenta color in combination with quinacridone pigment.
d 49, CISolvent Violet 10 is suitable.

The effect of the present invention is best exhibited when the dye used in the present invention is treated with a phenol resin before being dispersed in the binder resin. For the purpose of improving the dispersibility of the pigment, it may be added to the monomer when polymerizing the main binder resin, or may be treated together when the dye is subjected to phenol treatment. The method of treating the xanthene dye with the phenol resin in the present invention includes: (1) a method of melting and kneading the xanthene dye and the phenol resin with a two-roll mill, a Banbury mixer, a kneader, a three-roll mill, or the like; Dissolve the phenolic resin in a suitable solvent,
A method of removing and drying the solvent after dissolving or dispersing the xanthene dye, (3) a method of dissolving and dispersing the xanthene dye in a mixture of phenol and formaldehyde, adding an alkali, and subjecting the mixture to three-dimensional heating, (4) phenol A method of dissolving and dispersing a xanthene dye in a mixture of aldehyde and formaldehyde to prepare a novolak resin in the presence of an acid catalyst, and adding a crosslinking agent such as hexamethylenetetramine to cure the resin.

The content of the phenolic resin, the quinawalidone-based pigment, and the oil-soluble xanthene-based dye relative to 100 parts by weight of the styrene-based binder resin is 0.01 to 20 parts, preferably 0.1 to 5 parts, respectively.
0.5 to 20 parts, preferably 1 to 10 parts, 0.01 to 10 parts, preferably 0.
It is desirable to use 1 to 5 parts.

 This is for the following reason.

When the content of the phenolic resin is less than 0.01 part, there is almost no effect of preventing the dye from offsetting to the fixing roller, and the content of the phenolic resin exceeds 20 parts because it is easily colored by heat, light, oxygen and the like. This is because the color saturation of the copy image and the translucency of the OHP film are inferior.

When the amount of the quinacridone pigment is less than 0.5 part, the light resistance becomes poor.
This is because the transparency of the OHP film is inferior.

When the amount of the oil-soluble xanthene dye is less than 0.01 part, the effect of increasing the saturation by adding the dye is not recognized, and when the amount exceeds 10 parts, the light resistance is poor and the dyeing offset to the fixing roller tends to occur.

When the ratio of the oil-soluble xanthene dye to the phenol resin is in the range of 1:10 to 1: 0.1, the effect of preventing the dye of the phenol resin from dyeing to the fixing roller can be more sufficiently exhibited.

The color toner according to the present invention does not limit the negative charge property and the positive charge property. However, when producing a negative charge color toner, a charge control agent is added particularly for the purpose of stabilizing the negative charge property. Is preferred. In this case, a colorless or light-colored negative charge control agent that does not affect the color tone of the toner is preferable. Examples of the negative charge control agent include an organic metal complex such as a metal chain of an alkyl-substituted salicylic acid (for example, a chromium complex or a zinc complex of di-tert-butyl salicylic acid).

In the case of producing a positively chargeable color toner, an aminocarboxylic acid ester such as dimethylaminomethyl methacrylate showing a positive chargeability is used as a monomer in an amount of 0.1 to 40 m.
ol%, preferably 1 to 30 mol%, or a colorless or light-colored positive charge control agent which does not affect the color tone of the toner may be used. Examples of the positive charge control agent include quaternary ammonium salts represented by the structural formulas (II) and (III).

Structural formula (II) R ₁ , R ₂ , R ₃ , R ₄ ; the number of C is 1 to 10 alkyl groups or A phenyl group represented by R '; an alkyl group having 1 to 5 C atoms; R ₅ ; -H, -OH, -COOH, or an alkyl group having 1 to 5 C atoms. Structural formula (III) R ₆ ; an alkyl group having 1 to 5 C atoms R ₇ ; -H, —OH, —COOH, or an alkyl group having 1 to 5 C atoms The quaternary groups represented by the structural formulas (II) and (III) Among the ammonium salts, structural formulas (II) -1, -2 and structural formula (III) -1
It is preferable to use a positive charge control agent represented by the following formula, since it shows good chargeability with little dependence on the environment.

In addition, in the case of using a positively chargeable color toner, as a resin component of the binder resin, a positive charge control agent or a negative charge control agent when aminocarboxylates such as dimethylaminomethyl methacrylate are used. Use as needed.

In the case of a negatively chargeable color toner, the amount of the negative charge control agent used is preferably 0.1 to 15 parts by weight, more preferably 0.5 to 10 parts by weight, based on 100 parts by weight of the binder resin.

In the case of not using an aminocarboxylic acid ester such as dimethylaminomethyl methacrylate showing a positive charge property as a resin component in a positively chargeable color toner, a positive charge control agent is added in an amount of 0.1 to 100 parts by weight of the binder resin. It is desirable to use about 15 parts by weight, preferably 0.5 to 10 parts by weight. When using aminocarboxylic acid esters, if necessary for the purpose of imparting good chargeability with less environmental dependence,
It is desirable to use 0 to 10 parts by weight, preferably 0 to 8 parts by weight of the positive charge control agent and / or the negative charge control agent based on 100 parts by weight of the binder resin.

The color toner according to the present invention comprises these binder resin, colorant, and, if necessary, a charge control agent and / or a flow improver.

The particle size distribution of the color toner in the present invention is 3 to 16 μm, preferably 5 to 14 μm in volume average diameter, 5 μm or less in the number average distribution is 40% or less, preferably 35% or less, and 20.2 in the volume average distribution. μ or more is 8% or less, preferably 5% or less. This is because when the volume average diameter is 16 μ or more and / or 20.2 μ or more of the volume average distribution is 8% or more, the tendency of the image to become rough and bleeding, that is, the so-called scattering is increased. Also, the distribution amount of 5μ or less of the number average distribution, the so-called fine particle amount, is closely related to the scattering amount, and the fine powder amount of 40% or more is more than twice the scattering amount of the 30% fine powder amount in a more preferable embodiment. It has been found that In other words, the scattering causes fogging of the non-image portion and contamination of the charger wire, thereby significantly reducing the quality of the fixed image.

Further, in the color toner of the present invention, a fluidity improver may be added for the purpose of improving the fluidity of the toner.

As the flow improver used in the present invention, any one can be used as long as it can be added to the colorant-containing resin particles to increase the flowability before and after the addition.

For example, fluorine resin powder, that is, vinylidene fluoride fine powder, polytetrafluoroethylene fine powder, or the like; or a fatty acid metal salt, such as zinc stearate, calcium stearate, or lead stearate; or a metal oxide, that is, zinc oxide powder And fine powdered silica, that is, wet-processed silica, dry-processed silica, and surface-treated silica with a silane coupling agent, a titanium coupling agent, silicon oil, or the like.

Preferred flow improvers are fine powders produced by vapor phase oxidation of silicon halide compounds, so-called dry silica or fumed silica,
It is manufactured by a conventionally known technique. For example, it utilizes the thermal decomposition oxidation reaction of silicon tetrachloride gas in an oxyhydrogen flame, and the basic reaction formula is as follows.

SiCl ₄ + 2H ₂ + O ₂ → SiO ₂ 4HCl Also, in this manufacturing process, a composite fine powder of silica and another metal oxide is obtained by using another metal halide such as aluminum chloride or titanium chloride together with a silicon halide. Is possible and encompasses them.

The average particle diameter is preferably in the range of 0.001 to 2 μm, particularly preferably 0.002 to 0.2 μm.
It is preferable to use silica fine powder in the range of μ.

Examples of commercially available fine silica powder produced by vapor phase oxidation of a silicon halide used in the present invention include, for example, those commercially available as the following products.

AEROSIL (Nippon Aerosil) 130 200 300 380 TT600 MOX170 MOX 80 COK 84 Ca-O-SiL (CABOT Co.) M-5 MS-7 MS-75 HS-5 EH-5 Wacker HDK N20 (WACKER-CHEMIE GMB) V15 N20E T30 T40 D-C Fine Silica (Dow Corning Co.) Fransol (Fransil) Furthermore, treated silica fine powder obtained by hydrophobizing silica fine powder generated by gas phase oxidation of the silicon halide compound. More preferably, the body is used. It is particularly preferable that the treated silica fine powder is obtained by treating the silica fine powder such that the degree of hydrophobicity measured by a methanol titration test shows a value in the range of 30 to 80.

Hydrophobizing is applied by reacting with silica fine powder or chemically treating with an organic silicon compound or the like which physically adsorbs.

As a preferred method, silica fine powder produced by vapor phase oxidation of a silicon halide is treated with an organosilicon compound.

Examples of such organosilicon compounds include hexamethyldisilazane, trimethylsilane, trimethylclosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane,
Allylphenyldichlorosilane, benzyldimethylchlorosilane, bromomethyldimethylchlorosilane, α-chloroethyltrichlorosilane, ρ-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilylmercaptan, trimethylsilylmercaptan, triorganosilyl acrylate, Vinyldimethylacetoxysilane, dimethylethoxysilane, dimethyldimethoxysilane, diphenyldiethoxysilane,
Hexamethyldisiloxane, 1,3-divinyltetramethyldisiloxane, 1,3-diphenyltetramethyldicycloxane and 2 to 12 siloxane units per molecule, one for each terminal unit Examples include dimethylpolysiloxane containing a hydroxyl group bonded to Si.
These are used alone or as a mixture of two or more.

The treated silica fine powder preferably has a particle size in the range of 0.003 to 0.1 μm. Commercial products include Taranox-500 (Talco), AEROSIL R-972
(Nippon Aerosil).

For the positively chargeable toner, positively chargeable silica fine particles may be used in order to not only improve the fluidity but also obtain good chargeability that is less dependent on the environment.

In order to obtain such positively charged silica fine particles, it is preferable to treat them with a coupling agent containing an amino group or silicone oil. As such a treating agent, for example, H ₂ NCH ₂ CH ₂ CH ₂ Si (OCH ₃ ) ₃ H ₂ NCH ₂ CH ₂ CH ₂ Si (OC ₂ H ₅ ) ₃ H ₂ NCONHCH ₂ CH ₂ CH ₂ Si (OC ₂ H ₅ ) ₃ H ₂ NCH ₂ CH ₂ NHCH ₂ CH ₂ CH ₂ Si (OCH ₃ ) ₃ H ₂ NCH ₂ CH ₂ NHCH ₂ CH ₂ NHCH ₂ CH ₂ CH _{2 Si (OCH 3) 3 H 3} C 2 OCOCH 2 CH 2 NHCH 2 CH 2 CH 2 Si (OCH 3) 3 H 5 C 2 OCOCH 2 CH 2 NHCH 2 CH 2 NHCH 2 CH 2 CH 2 Si (OCH 3) 3 _{(H 2 CO) 3 SiCH 2} CH 2 CH 2 -NHCH 2 (H 2 CO) 3 SiCH 2 CH 2 CH 2 -NHCH 2 H ₂ CNHCH ₂ CH ₂ CH ₂ Si (OC ₂ H ₅ ) ₃ H ₂ N (CH ₂ CH ₂ NH) ₂ CH ₂ CH ₂ CH ₂ Si (OCH ₃ ) ₃ H ₃ C-NHCONHC ₃ H ₆ Si (OCH ₃ ) There are aminosilane coupling agents such as ₃ .

As the silicone oil, an amino-modified silicone oil having a partial structure having an amino group in a side chain represented by the following formula is generally used.

(Here, R ₁ represents hydrogen, an alkyl group, an aryl group, or an alkoxy group, R ₂ represents an alkylene group, a phenylene group, and R ₃ and R ₄ represent a hydrogen, an alkyl group, or an aryl group. The alkyl group, the aryl group, the alkylene group, and the phenylene group may contain an amine or may have a substituent such as halogen as long as the chargeability is not impaired. The following are examples of such silicone oils having an amino group.

In addition, the amine equivalent is the equivalent (g /
eqiv) is the value obtained by dividing the molecular weight by the number of amines per molecule.

It is preferable to use these silica fine particles treated with a coupling agent or a silicone oil containing an amino group, after further hydrophobizing them with the aforementioned organosilicon compound.

For the color toner of the present invention, the carrier used at the time of development also plays an important role so that the effect can be sufficiently exhibited.

Examples of the carrier used in the present invention include, for example, surface-oxidized or unoxidized iron, nickel, copper, zinc, cobalt,
Metals such as manganese, chromium, and rare earths and alloys or oxides thereof and ferrites can be used. There is no particular restriction on the manufacturing method.

Further, a system in which the surface of the carrier is coated with a resin or the like is particularly preferable in the J / B developing method described above. Conventionally known methods such as a method in which a coating material such as a resin is dissolved or suspended in a solvent and applied and impregnated into a carrier, or a method in which the coating material is simply mixed with a powder, can be applied.

The substance fixed to the carrier surface varies depending on the toner material. Examples thereof include polytetrafluoroethylene, monochlorotrifluoroethylene polymer, polyvinylidene fluoride, silicone resin, polyester resin, metal complex of ditersharry butylsalicylic acid, styrene resin, and acrylic resin. It is appropriate to use one or more of a series resin, polyacid, polyvinyl butyral, nigrosine, amino acrylate resin, basic dye and its lake, fine powder of Irica, fine powder of alumina, etc., but it is not necessarily limited thereto.

The amount of the compound to be treated may be appropriately determined so that the carrier satisfies the above conditions, but is generally desirably 0.1 to 30% by weight (preferably 0.5 to 20% by weight) based on the carrier of the present invention.

The average particle size of these carriers is 10 to 100μ, preferably 2
It is preferred to have 0-70μ.

A particularly preferred embodiment is a ternary ferrite of Cu-Zn-Fe whose surface is a combination of a resin such as a fluorine resin and a styrene resin, for example, polyvinylidene fluoride and a styrene-methyl methacrylate resin; Fluoroethylene and styrene-methyl methacrylate resin, fluorine-based copolymer and styrene-based copolymer; such as 90:10 to 20:80, preferably a mixture of 70:30 to 30:70, 0.01-5% by weight, preferably 0.1-1
Coated ferrite carrier having the above-mentioned average particle size, in which the carrier particles are coated by weight and are 250 mesh pass, 400 mesh on, and 70 mesh% or more. Examples of the fluorine-based copolymer include vinylidene fluoride-tetrafluoroethylene copolymer (10:90 to 90:10), and examples of the styrene-based copolymer include styrene-2-ethylhexyl acrylate (20:80 to 90%). 80:20), styrene-2-ethylhexyne acrylate-methyl methacrylate (20
To 60: 5 to 30:10 to 50).

The coated ferrite carrier has a sharp particle size distribution, provides favorable triboelectrification to the color toner of the present invention, and has the effect of improving electrophotographic properties.

When the two-component developer is prepared by mixing with the color toner according to the present invention, the mixing ratio is 2.0% by weight to 15% by weight, preferably 4% by weight to 13% by weight, as the toner concentration in the developer.
Good results are usually obtained with a percentage by weight. If the toner density is less than 2.0%, the image density becomes low and it becomes impractical
Above, fog and in-machine scattering are increased, and the useful life of the developer is shortened.

 Hereinafter, each measurement method in the present invention will be described.

(1) Measurement of Molecular Weight In the present invention, the maximum value of the molecular weight of a chromatogram by GPC (gel permeation chromatography) is measured under the following conditions.

That is, the column was stabilized in a heat chamber at 40 ° C, and THF was added to the column at this temperature as a solvent.
(Tetrahydrofuran) is flowed at a flow rate of 1 ml per minute, and a THF sample solution of the resin adjusted to a sample concentration of 0.05 to 0.6% by weight is injected and measured. In measuring the molecular weight of the sample, the molecular weight distribution of the sample was calculated from the relationship between the logarithmic value of a calibration curve prepared using several types of monodisperse polystyrene standard samples and the count number. Standard polystyrene samples for preparing calibration curves include, for example, Pressure Chemi
cal Co. or Toyo Soda Kogyo Co., Ltd.
× 10 ² , 2.1 × 10 ³ , 4 × 10 ³ , 1.75 × 10 ⁴ , 5.1 × 10 ⁴ , 1.1 × 10 ⁵ ,
It is suitable to use 3.9 × 10 ⁵ , 8.6 × 10 ⁵ , 2 × 10 ⁶ , 4.48 × 10 ⁶ and at least about 10 standard polystyrene samples. An RI (refractive index) detector is used as the detector.

In order to accurately measure the molecular weight region of 10 ³ to 2 × 10 ^6, a plurality of commercially available polystyrene gel columns are preferably used. For example, μ-styr manufactured by Waters, Inc.
agel 500,10 ³ , 10 ⁴ , 10 ⁵ combination or Showa Denko
shodex KF-80M, KF-801,803,804,805 combination, KA
-802, 803, 804, 805 combination, or Toyo Soda T
SKgel G1000H, G2000H, G2500H, G3000H, G4000H, G5000H, G6
A combination of 000H, G7000H and GMH is preferred.

(2) Measurement of glass transition temperature Tg In the present invention, measurement is performed using a differential thermal analysis measurement device (DSC measurement device), DSC-7 (manufactured by PerkinElmer).

The measurement sample is precisely weighed in an amount of 5 to 20 mg, preferably 10 mg.

Put this in an aluminum pan and use an empty aluminum pan as a reference.
The measurement is performed at normal temperature and normal humidity at a heating rate of 10 ° C./min.

In this heating process, an endothermic peak of a main peak in a temperature range of 40 to 100 ° C. is obtained.

The intersection of the line of the midpoint of the baseline before and after the endothermic peak appears and the differential heat curve is defined as the glass transition temperature Tg in the present invention.

[Examples] Hereinafter, the present invention will be described in detail with reference to Examples.

Example of Resin Synthesis A reactor was charged with 200 parts by weight of cumene and heated to a reflux temperature. A mixture obtained by adding 8 parts by weight of di-tert-butyl peroxide to a monomer mixture having a weight ratio of styrene / butyl acrylate = 91/9 was added dropwise over 4 hours under reflux of cumene. Furthermore, the solution polymerization was completed under cumene reflux (146 ° C to 156 ° C), and cumene was removed. The resulting polymer is
It was soluble in THF, Mw = 5800, Mw / Mn = 2.0, the molecular weight at which the main peak of GPC was located was 4,500, and Tg = 60 ° C.

The GPC chart is shown in FIG. 1 where the polymer is a.

Next, 70 parts by weight of the polymer a was dissolved in 200 parts by weight of cumene, and the same method as above was repeated using 30 parts by weight of a monomer mixture having a weight ratio of styrene / butyl acrylate = 78/22 and 1 part by weight of di-tert-butyl peroxide. Perform solution polymerization with
Cumene was removed to obtain resin A.

Resin A is soluble in THF, Mw = 13000, Mw / Mn = 4.4,
Tg = 59 ° C., the molecular weight at which the main peak of GPC was located was 5,000. The GPC chart is shown in FIG.

FIG. 3 shows the molecular weight distribution of the resin A when the polymer a was not added. Mw = 38000, Mw / Mn = 2.7, GPC peak molecular weight 27,000, Tg = 59 ° C.

Hereinafter, the resins B to G were appropriately synthesized by changing the styrene / acryl ratio, the amount of the initiator, the ratio of the polymer mixture, and the like. In particular, Resin E is a polymer which is polymerized using a crosslinking agent and about 1.0 part by weight of benzoyl peroxide as an initiator and containing a gel component insoluble in THF. Using a Soxhlet extractor, this gel fraction was used for resin 0.5-1.0.
g, determined from the dry weight of the insoluble matter after extraction for 6 hours.

Example 1 Is melt-kneaded by a roll mill, cooled, coarsely crushed, finely crushed, and further classified to have a volume average of 8.0 μm, 5 μm or less.
%, 20.2 μm or more and 0% of a classified product were obtained. A magenta toner was prepared by externally adding 0.5 parts by weight of silica fine powder treated with hexamethyldisilazane as a flow improver and 0.2 parts by weight of aluminum oxide fine powder to 100 parts by weight of the classified product.

As a carrier, styrene-acryl 2-ethylhexyl-methyl methacrylate (copolymer weight ratio 50:20:30)
Using a Cu-Zn-Fe-based ferrite carrier (average particle size 47.2 μm, 250 mesh pass, 400 mesh on 87 wt%) coated with 0.5 wt%, a developer was prepared so that the toner concentration was 5 wt%.

Using these developers and toners, an image output test was performed using a full-color copying machine CLC-1 manufactured by Canon.

As a result, there was no offset to the fixing roll even after printing of 100,000 sheets in the magenta single color mode, and a full-color image faithfully reproducing the original color chart without fog was obtained. The toner transportability in the copying machine was good, and a stable image density was obtained.

Even when an OHP film was used, the transparency of the toner was very favorable. Further, an image output test was conducted by changing the environment to low temperature, low humidity, and high temperature and high humidity. As a result, good results were obtained with stable image density, no fog, and almost no toner scattering.

The image obtained here was irradiated with sunlight for three months, but each color did not fade and was the same as when the image was formed.

Example 2 The same procedure as in Example 1 was carried out except that 100 parts by weight of Resin B of Resin Synthesis Example was used, and the volume average particle size was 8.21 μm and 5 μm or less.
Classified products of 5%, 20.2 μm or more and 0% were obtained. Thereafter, the same operation as in Example 1 was performed to obtain a toner and a developer.

Using these developers and toners, an image output test was performed using a full-color copying machine CLC-1 manufactured by Canon.

As a result, there was no offset to the fixing roll even after printing for 12,000 sheets in the magenta single color mode, and a full-color image faithfully reproducing the original color chart without fog was obtained. The toner transportability in the copying machine was good, and a stable image density was obtained.

Even when an OHP film was used, the transparency of the toner was very favorable. Further, an image output test was conducted by changing the environment to low temperature, low humidity, and high temperature and high humidity. As a result, good results were obtained with stable image density, no fog, and almost no toner scattering.

The image obtained here was irradiated with sunlight for three months, but each color did not fade and was the same as when the image was formed.

Example 3 Was performed in the same manner as in Example 1 except that
Classified products of 98 μm, 5 μm or less 31.0%, 20.2 μm or more and 0% were obtained. Thereafter, the same operation as in Example 1 was performed to obtain a toner and a developer.

Using these developers and toners, an image output test was performed using a full-color copying machine CLC-1 manufactured by Canon.

As a result, there was no offset to the fixing roll even after printing of 11,000 sheets in the magenta single-color mode, and a full-color image faithfully reproducing the original color chart without fog was obtained. The toner transportability in the copying machine was good, and a stable image density was obtained.

Even when an OHP film was used, the transparency of the toner was very favorable. Further, an image output test was conducted by changing the environment to low temperature, low humidity, and high temperature and high humidity. As a result, good results were obtained with stable image density, no fog, and almost no toner scattering.

The image obtained here was irradiated with sunlight for three months, but each color did not fade and was the same as when the image was formed.

Example 4 The same procedure as in Example 1 was carried out except that 100 parts by weight of Resin D of Resin Synthesis Example was used.
%, 20.2 μm or more and 1.2% of a classified product were obtained. Thereafter, the same procedure as in Example 1 was carried out except that aluminum oxide was not used as a flow improver, to obtain a toner and a developer having a toner concentration of 8%.

Using these developers and toners, an image output test was performed using a full-color copying machine CLC-1 manufactured by Canon.

As a result, there was no offset to the fixing roll even after printing of 13,000 sheets in the magenta single-color mode, and a full-color image faithfully reproducing the original color chart without fog was obtained. The toner transportability in the copying machine was good, and a stable image density was obtained.

Even when an OHP film was used, the transparency of the toner was very favorable. Further, an image output test was conducted by changing the environment to low temperature, low humidity, and high temperature and high humidity. As a result, good results were obtained with stable image density, no fog, and almost no toner scattering.

The image obtained here was irradiated with sunlight for three months, but each color did not fade and was the same as when the image was formed.

Example 5 A positive charge control agent represented by the aforementioned structural formula (II) -1 was
Except that 3.0 parts by weight were used, the same procedure as in Example 1 was carried out to obtain a classified product having a volume average particle diameter of 11.8 μm, 5% or less 7.5%, and 20.2 μm or more 0.5%. Thereafter, 0.5 part by weight of silica treated with silicone oil having amino groups (KE-857) as a flow improver was externally added to obtain a magenta toner. Thereafter, a developer having a toner concentration of 8% was obtained in the same manner as in Example 4.

Canon copiers using these developers and toners
An image output test was performed using NP-4835.

As a result, there was no offset to the fixing roll even after printing of 100,000 sheets in the magenta single color mode, and a full-color image faithfully reproducing the original color chart without fog was obtained. The toner transportability in the copying machine was good, and a stable image density was obtained.

Even when an OHP film was used, the transparency of the toner was very favorable. Further, an image output test was conducted by changing the environment to low temperature, low humidity, and high temperature and high humidity. As a result, good results were obtained with stable image density, no fog, and almost no toner scattering.

The image obtained here was irradiated with sunlight for three months, but each color did not fade and was the same as when the image was formed.

Comparative Example 1 The procedure of Example 1 was repeated except that 100 parts by weight of Resin E of Resin Synthesis Example was used, and the volume average particle size was 8.31 μm and 5 μm or less.
Classified products of 0%, 20.2 μm or more and 0% were obtained. Thereafter, the same operation as in Example 1 was performed to obtain a toner and a developer.

Using these developers and toners, an image output test was performed using a full-color copying machine CLC-1 manufactured by Canon.

As a result, there was no offset to the fixing roller even after the endurance of 0.8000 sheets in the magenta single color mode, but the flatness of the copy image fixing surface was poor, so that a dark color image having poor color mixing was obtained.

Comparative Example 2 The same procedure was performed as in Example 3 except that 100 parts by weight of Resin F of Resin Synthesis Example and CI Solvent Violet 10 was not treated with a phenol resin, and the volume average particle size was 8.38 μm, 5.
A classified product having a particle size of 28.0% or less and 20.2% or more and 0% or less was obtained. Thereafter, the same operation as in Example 3 was performed to obtain a toner and a developer.

Using these developers and toners, an image output test was performed using a full-color copying machine CLC-1 manufactured by Canon.

As a result, in the magenta single-color mode, an offset to the fixing roller after printing for 30,000 sheets occurred.

Comparative Example 3 The same procedure as in Example 1 was carried out except that 100 parts by weight of Resin G of Resin Synthesis Example was used, and the volume average particle size was 12.2 μm and 5 μm or less.
%, 20.2 μm or more and 1.6% were obtained. Thereafter, the same operation as in Example 4 was performed to obtain a toner and a developer.

Using these developers and toners, an image output test was performed using a full-color copying machine CLC-1 manufactured by Canon.

As a result, after printing for 200 sheets in the magenta single color mode, the toner that had been offset at a low temperature on the fixing roller began to appear on the copy image, and the entire sheet was offset on 300 sheets.

[Effects of the Invention] According to the toner of the present invention, there is no deterioration in dyeing of the fixing roller and excellent offset resistance, and a smooth fixing surface can be formed, and a very clear color image can be obtained. it can.

[Brief description of the drawings]

FIG. 1 is a GPC chart of polymer a, and FIG. 2 is resin A.
FIG. 3 shows a GPC chart of Resin A when no polymer a was added.

Claims (2)

(57) [Claims] 1. A color toner mainly comprising a styrene resin as a binder resin at least and a phenolic resin, a quinacridone pigment and an oil-soluble xanthene dye, wherein the styrene resin has a molecular weight distribution determined by GPC.
The proportion of the area A having a molecular weight of less than 10,000 is 55 to 80%, the proportion of the area B having a molecular weight of 10,000 to 50,000 is 5 to 25%, and the proportion of the area C having a molecular weight exceeding 50,000 is 5 to 20%. A color toner, characterized in that: 2. The styrenic resin is a styrenic copolymer obtained by copolymerizing a styrenic monomer with one or more monomers selected from the group consisting of acrylic acids and methacrylic acids. Claim 1
2. The color toner according to 1.