JPH01224776A - Color toner and method for fixing same - Google Patents

Abstract

PURPOSE:To enhance durability by using specified polyester resin contg. an etherified diphenol component, dicarboxylic acid and polycarboxylic acid other than dicarboxylic acid as binding resin. CONSTITUTION:Polyester resin contg. at least 40-60mol.% etherified diphenol component basing on the total amt. of all the constituent monomers, 10-40mol.% dicarboxylic acid substd. by 6-16C hydrocarbon group or deriv. thereof and 1-20mol.% polycarboxylic acid other than dicarboxylic acid and/or polyol or deriv. thereof is used as binder resin. The polyester resin has 10<5>-2X10<6>P apparent melt viscosity at 100 deg.C, 2X10<4>-4X10<5>P at 110 deg.C and 55-70 deg.C peak heat absorption temp. in DSC and ensures satisfactory fixability, color mixability, triboelectric chargeability, high glossiness for enhancing the quality of an image and superior durability.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an electrophotographic toner, and more particularly to a color toner in which the durability of a fixing roller is significantly improved.

[Prior Art] Conventionally, as an electrophotographic method, US Pat. No. 2297E191
Specification, Japanese Patent Publication No. 42-23910 and Japanese Patent Publication No. 4
A number of methods are known, such as those described in Japanese Patent No. 3-24748, but generally a photoconductive substance is used to form an electrical latent image on a photoreceptor by various means, and then the latent image is The image is developed using toner, and if necessary, the toner image is transferred to a transfer material such as paper, and then fixed by heating or pressure to obtain a copy.

Furthermore, various developing methods are known in which an electrical latent image is visualized using toner.

For example, the magnetic brush method described in US Pat. No. 2,874,083, the cascade development method described in US Pat. No. 2,818,552, the jumping-brush development method described in JP-A-62-63970, liquid developability, etc. This developing method is known. As toners used in these developing methods, fine powders in which dyes and pigments are dispersed in natural or synthetic resins have conventionally been used. Furthermore, it is also known to use fine developing powder to which a third substance is added for various purposes.

In recent years, there has been a rapid shift from black-and-white copying machines to full-color copying machines, and two-color copying machines and digitized full-color copying machines are also beginning to be released in the market.

Color image formation by full-color electrophotography generally requires 3
All colors are reproduced using toner of the three primary colors of yellow, magenta, and cyan, or four colors including black.

In this numerical method, first, light from an original is passed through a color-separating light transmitting filter whose color is complementary to that of the toner to form an electrostatic latent image on a photoconductive layer. The toner is then held on the support through development and transfer steps. Next, the above-mentioned steps are sequentially performed several times, and the toners are superimposed on the same support while registering, and a final full-color image is obtained by fixing only one time.

In color electrophotography, which requires multiple development steps and the overlapping of several toner layers of different colors on the same support in the fixing process, the fixing properties that color toners should have are extremely important. This is an important element.

That is, the fixed color toner needs to suppress diffused reflection due to toner particles as much as possible and have appropriate gloss and luster.

In addition, the color toner must have transparency that does not prevent toner layers of different tones located below the toner layer, and must have a wide color reproducibility.

As a color toner that can satisfy these requirements, the present applicant et al.
No. 25 and Japanese Unexamined Patent Publication No. 59-57258 have disclosed novel combinations of color binder resins and colorants.

These color toners have considerable sharp melting properties, and when used in combination with a silicone rubber roller that maintains elasticity with a hardness of 20 to 50 degrees and is vulcanized at room temperature or low temperature and can be coated with silicone oil, During fixing, the shape of the toner changes to a state close to complete melting, resulting in favorable gloss and color reproducibility.

These effects, as described in the 4th Non-Impact Printing Technology Symposium Proceedings 2129-(19B?), are based on placing more emphasis on the viscosity term than the elastic term in the viscoelastic properties of the binder resin as the toner fixing property. It means.

That is, when heated, the toner behaves more like a viscous body, has increased thermal meltability, and can also provide gloss.

However, such a binder resin design that emphasizes viscosity inevitably reduces the intermolecular cohesive force during thermal melting, and increases the adhesion of toner to the heated roller when passing through the fixing device. . These causes a high temperature offset phenomenon.

In particular, when a silicone rubber roller is used as a fixing roller, high-temperature offset is likely to occur due to a reduction in the essential mold release properties of the silicone rubber surface due to repeated use, regardless of whether release oil is applied or not. When a silicone rubber roller is first used, it is possible to maintain a certain degree of mold releasability due to the smoothness and cleanliness of the roller surface. However, as color copies continue to be copied, as the image area is large and the amount of toner retained on the support is much larger than that of black and white copies, the releasability of the roller gradually decreases. do. The speed at which the mold releasability deteriorates is several times that of black and white copying.

Further, since the conch itself has almost no elasticity as mentioned above, it is powerless to provide offset resistance. As a result, a toner film or granular deposits are formed on the roller surface after just a few thousand to tens of thousands of copies, and a so-called high-temperature offset occurs in which the upper layer of toner on the image surface that passes through the heated roller is stripped off. .

Various measures have been attempted for fixing devices and toner to solve or alleviate the above problems, but it cannot be said that a sufficient solution has been achieved yet.

As the fixing device, a material with excellent surface releasability is used. Alternatively, efforts have been made to apply oil to the rollers, and most of the thermal roller fixing devices of copying machines currently on the market use some form of oil application. However, applying a large amount of oil to improve mold releasability causes undesirable problems such as oil stains on the sheet and increased cost.

Furthermore, in order to increase releasability, low-molecular-weight polyethylene or wax that melts sufficiently when heated is added to the toner, but although it is effective in preventing offset, the addition of a large amount is difficult for color toners. Adverse effects such as impairing the transparency of OHP images, unstable charging characteristics, and decreased durability are also observed, and it is difficult to say that they are sufficient.

In addition, as a problem unique to color copying, at least three color toner colors, preferably four colors, must be balanced in harmony, and it is meaningless to discuss only the fixing characteristics and color reproducibility of colors. There is no.

In principle, if we have the three primary colors of yellow, magenta, and cyan, it should be possible to reproduce almost all colors using the primary color mixing method, which is why full-color copiers currently on the market has a structure in which three primary color toners are used in a superimposed manner. Ideally, this would make it possible to achieve any color in any density range, but in reality, there are still areas that need to be improved, such as the spectral reflection characteristics of toner, the mixing properties of toners when overlapping and fixing, and the decrease in saturation. have.

When obtaining black by superimposing three colors, as described above, three times as many toner layers are formed on the transfer paper as in the case of a single color, and it is also difficult to maintain offset resistance.

[Problems to be Solved by the Invention] The purpose of the present invention is to: (1) exhibit good fixing properties and color mixing properties, (2) have sufficient triboelectric charging properties, and (2) have high gloss that significantly improves image quality in full-color copying. , ■ To provide a color toner that is resistant to carrier waste and has excellent durability even when repeatedly copied, and another purpose is to: 10 sufficiently prevent high temperature offset and have a wide fixable temperature range; It is an object of the present invention to provide a fixing method that maintains offset resistance even when the fixing sheet is passed through.

[Means and effects for solving the problem] The present inventors,
In order to achieve the above object, the present invention has been completed as a result of intensive research. That is, the color toner of the present invention contains the etherified diphenol component in an amount of 40 to Hmar! of the total monomer amount. %
and a divalent carboxylic acid substituted with a C6 to C16 hydrocarbon group or its derivative component in an amount of 10 to 4 of the total monomer amount.
0 moji% and trivalent or higher polycarboxylic acid or/
and polyols, or their derivative components in an amount of 1 to 20 lof! of the total monomer amount! containing at least % and
100”0.

The apparent melt viscosity at 110°C is 105 to 2x, respectively!
06 poise, 2X104~4x105 voice tear,
The color toner is characterized in that the binder resin is a polyester resin having an endothermic peak temperature of 55 to 70°C in DSC. Furthermore, the fixing method of the present invention is used in color copying, in which an electrostatic latent image obtained by exposing a document to color separation is developed with primary color toners, each toner image is superimposed and transferred onto a transfer paper, and then fixed by a heating roller. , the etherified diphenol component is 40~HmoI of the total monomer amount! %
and a divalent carboxylic acid substituted with a C6 to G+6 hydrocarbon group or a derivative thereof in an amount of 10 to 4 of the total monomer amount.
0 moR% and at least 1 to 20 tea1% of the total monomer amount of trivalent or higher polycarboxylic acid or/and polyols, or their derivative components, and the apparent melting temperature of 100 ° C. and 110 ° C. Viscosity is 105~2X 106 poise, 2X104~4X respectively
105 poise, a color toner with a polyester resin binder having an endothermic peak temperature of 55 to 70°C in DSC, a rubber-like elastic layer on the core metal, and an offset prevention layer on the surface layer. This color toner fixing method is characterized in that it uses a hot roller fixing device comprising a fixing roller made of rubber and a pressure roller having a rubber-like elastic layer on a core metal.

The present invention will be explained in detail below.

The color toner of the present invention using polyester resin is
The melt viscosity is quite high in consideration of high temperature offset, and a temperature of at least 210° C. is required to obtain sufficient color mixing properties and gloss as a color toner in combination with a fixing device having a silicone rubber roller. At this temperature, the silicone rubber roller exceeds its heat resistance limit, so its durability against green-back copying is low.

The present inventors have proposed that the roller used in combination with the color toner of the present invention, which has excellent offset resistance, can produce color copies that are equivalent to or better than those obtained by the combination of a conventional binder resin with sharp melt properties and a silicone rubber roller. Color mixing and
We found a material for the heat roller for fixing that provides sharpness,
The invention has been completed.

The fixing roller used in the fixing method of the present invention does not deform even when a pressure sufficient to transfer heat to the overlapping color toner layer on the transfer material is applied, and the roller surface wraps around the color toner layer. It has a certain degree of elasticity. Moreover, even if color copying is repeated, the releasability of the roller surface is maintained.

The fixing device used in the fixing method of the present invention includes a fixing roller having a rubber-like elastic layer on a core metal and an offset prevention layer on a surface layer, and a pressurizing roller having a rubber-like elastic layer on a core metal. This is a heat roller fixing device consisting of a roller.

Examples of the rubber-like elastic body used in the pressure roller and fixing roller of the present invention include silicone rubber.

Polybutadiene rubber, polychloroprene rubber.

Examples include fluororubber, acrylic rubber, polyisoprene rubber, urethane rubber, and butadiene styrene rubber.

In particular, as the rubber-like elastic body for the fixing roller, vulcanized silicone rubber such as HTV silicone rubber (high temperature vulcanization), LT
V silicone rubber (low temperature vulcanization) and RTV silicone rubber (room temperature vulcanization) are preferred, and their thickness is 0.2 to 5. h+i
, preferably 0.3 to 4.0 times a day. 5.0+++
If it is more than +s, the heat conductivity from the core metal deteriorates, and there is an increased tendency for the fixing roller to be delayed in returning to a predetermined temperature after the transfer paper carrying the toner passes through the natural roller. Also, 0
．． If it is less than 2++ m, the elasticity of the fixing roller decreases and the effect of enveloping the color toner is drastically reduced, resulting in poor color reproducibility and gloss using the toner of the present invention, making it unsuitable for color copy images.

On the other hand, the rubber-like elastic body used in the pressure roller is preferably silicone rubber or fluororubber, and may have a thin film of fluororesin or fluorine latex on its surface in order to further maintain mold release properties.

The thickness of the pressure roller is 0.2 to 9.5+sm, preferably 0.5 to 8.0sm.

Examples of the offset prevention layer on the surface layer of the rubber-like elastic body in the fixing roller include fluororesin, styrene resin, acrylic resin, and polyester resin.

There are styrene-acrylic resins, epoxy resins, urethane resins, polyethylene resins, and polypropylene resins. Fluorine resins and silicone resins are preferable because they reduce surface energy and take shapeability into consideration. Furthermore, consider applying silicone oil to the fixing roller. And silicone resin is particularly preferred.

The thickness of the resin is an important factor determining the durability of the fixing roller, and is from 10.0 to 0.0 pm, preferably from 15.0 to 100.0 μm.

If the thickness is less than 10.0 ILm, the resin surface will be scratched, /\
Scratches occur after only a few thousand copies, and there is no durability at all.

Further, a thickness of 100 mm or more is not preferable because it impairs the effect of the rubber-like elastic body in the lower layer of the resin and deteriorates the color fixation.

Those that can be used as the etherified diphenol component of the polyester resin used in the present invention are polyoxystyrene (I()-2,2-bis(4-hydroxyphenyl)propane, polyhydroxybutylene (2)-2, 2-
Bis(4-hydroxyphenyl)propane, polyoxyethylene(3)-2,2-bis(4-hydroxyphenyl)propane, polyoxypropylene(3)-bis(4)
-hydroxyphenyl)thioether, polyoxyethylene (2)-2,6-dichloro-4-hydroxyphenyl, 2',3',6'-trichloro4'-hydroxyphenylmethane, polyoxypropylene (3)-2- Furomo 4-hydroxyphenyl, 4-hydroxyphenyl ether, polyoxyethylene (2,5)-P-P-bisphenol, polyoxybretin (4) bis(4-hydroxyphenyl) ketone, polyoxystyrene (7)
-bis(4-hydroxyphenyl)ether, polyoxyethylene(3)-2,2-bis(2,6-diaiodo-4-hydroxyphenyl)propane and polyoxypropylene(2,2)2,2-bis( 4-hydroxyphenyl)furopane.

A preferred etherified diphenol group in the present invention is etherified bisphenol. A preferred group of etherified bisphenols are those that are ethoxylated or propoxylated, with a concentration of 2 to 3 per mole of bisphenol.
having moles of oxyethylene or oxypropylene,
R is propylene or a sulfone group. Examples of this group are polyoxyethylene (2,5)-bis(
2,6-dipromo4-hydroxyphenyl)'sulfone, polyoxypropylene (3)-2,2-bis(2,
5-difluoro-4-hydroxyphenyl)propane and polyoxyethylene(1.5)-polyoxypropylene(1,0)-bis(4-hydroxyphenyl)sulfone.

Another preferred group of etherified bisphenols falling into the group characterized by the above formula is polyoxypropylene 2
・2'-bis(4-hydroxyphenyl)propane and polyoxyethylene or polyoxypropylene 2.
2-bis(4-hydroxy.

2,6-dichlorophenyl)furopane (the number of oxyalkylene units per mole of bisphenol is 2.1 to 2.
5).

The content of etherified diphenol is 4% of the total monomer amount.
0-80 tma1%, preferably 45-55 raa
i! %. When it is less than 40 mob%, the amount of acid in the total monomer increases relatively, which affects the moisture resistance properties.

Moreover, if the Go mo is 1% or more, the triboelectric charging property with the carrier will be adversely affected.

In addition, examples of the divalent carboxylic acid substituted with a 06 to C16 hydrocarbon group, particularly an alkyl group or/and an alkenyl group include n-butylsuccinic acid, n-cutylsuccinic acid,
In-octylsuccinic acid, iso-dodecylsuccinic acid, n
- The amount of dodecenylsuccinic acid, etc. is increased. Its content is 10-40 moj)% of the total monomer amount, preferably 1
2~3511Or! %.

Examples of trivalent or higher polycarboxylic acids include 1, 2, and 4 benzenetricarboxylic acid, including its esters.

1,2,5 benzenetricarboxylic acid, 1,2,4 cyclohexanetricarboxylic acid, 2,5,7 naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid.

1,2,4 butanetricarboxylic acid, 1,2,5 hexanetricarboxylic acid, 1,3-dicarboxyl-2-methylenecarboxylpropane, 1,3-dicarboxyl-2
-Methyl-2-methylenecarboxylpropane, tetra(methylenecarboxyl)methane, l.2.-7.8 octane tetracarboxylic acid, etc. can be used.

Particularly preferred trivalent or higher carboxylic acids include trimellitic acid and pyromellitic acid.

The content is 1-20% of the total monomer amount, preferably 3-1511oR%, more preferably 4-12Il
of! %. Examples of trivalent or higher polyols include sorbitol and 1,2,3,8-hexanethetol.

1.4 ~ Sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol.

Sucrose, l-2-4-mesitatriol, glycerin.

2-methylpropanetriol, 2-methyl-1.2.
4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxymethylbenzene, etc. can be used. Polycarboxylic acids and polyols, which are non-linear components, are contained in the polyester in an amount of 1 to 20 m
It is preferable that the polyols are contained in 1OIIOf! % or less is preferable. If the content of the polycarboxylic acid or polyol is 20 mof'% or more, or if the polyol alone is 10 rsoR% or more, the moisture resistance will deteriorate and the charging characteristics will become unstable. Conversely, if the total amount of polycarboxylic acid and polyol is less than 1 ma12%,
Offset resistance tends to deteriorate.

In addition, in the present invention, acid monomers that may be included include divalent carboxylic acids, such as fumaric acid, maleic acid, malonic acid, curtaric acid, cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid, phthalic acid, etc.
and their anhydrides, lower alkyl esters, etc.

In the present invention, the combination of etherified bisphenol and carboxylic acid that can exhibit even greater effects is polyoxypropylene (2.2
)-2,2-bis(4-hydroxyphenyl)propane, polyoxyethylene (2,2)-2,2-bis(4-
Hydroxyphenyl)propane alone or as a mixture; divalent carboxylic acids include terephthalic acid and fumaric acid; carboxylic acids substituted with C6 to C16 hydrocarbon groups include n-dodecenylsuccinic acid and n-cutylsuccinic acid; As the trivalent or higher carboxylic acid, trimellitic acid pyromellitic acid and the like are preferable.

The resulting polyester binder has a glass transition temperature of 55 to 70°C and a weight average molecular weight of 9000 to 1000.
Preferably it is 00. In addition, its acid value is 2.0~
95. It is important that the number is preferably 2 to 50. When the acid value is less than 2, the number of functional groups contributing to triboelectric charging decreases, and charging tends to be insufficient. When it is more than 50, the affinity of the polyester binder with water increases, resulting in poor moisture resistance.

In addition, the present inventors have conducted various studies to improve the dispersion of colorants in polyester binder resins using etherified diphenols, and have found that a small amount of addition has a sufficient effect, and other properties have been improved. We have discovered a new dispersion improver that has no adverse effects. Generally, it is difficult to disperse colorants into polyester resins than in styrene-acrylic resins, and it is particularly difficult to disperse colorants into polyester resins having a network structure as in the present invention.

In other words, in combination with the polyester binder resin of the present invention, it achieves the extremely important performance of a color toner: sharpness of color tone, maintenance of sufficient image density, and wide color reproducibility due to improved dispersibility of the colorant. Possible new materials include:
Examples include organometallic complexes containing metals having an atomic number of 12-14° or 24-30.

Effective organic complexes of the metal salts mentioned above include, for example, impropoxide metal complexes, acetylacetone metal complexes, and salicylate metal complexes, and a specific example thereof is aluminum isopropoxide.

Examples include magnesium acetylacetonate, iron (II) acetylacetonate, zinc salicylate, acetylsalicylic acid, zinc, and aluminum 3.5-di-tert-butylsalicylate. Examples that are particularly suitable for the present invention include aluminum 3,5-di-tert-butylsalicylate, zinc 3,5-di-tert-butylsalicylate, and chromium 3,5-di-tert-butylsalicylate.

The amount added is 0.2 to 10 parts by weight, preferably 0.5 to 7 parts by weight, based on the concentrated Mljfl fat. If the amount is less than 0.2 parts by weight based on the binder resin, there will be almost no dispersion improving effect, and if it exceeds 10 parts by weight, the addition will not substantially improve the effect.

Coloring agents suitable for the purpose of the present invention include the following pigments or dyes. In addition, in the present invention, C,1,Disperse Y1O4,C,I, which has poor light resistance.

5olvent Y7? and C,1,5olvent
Colorants such as Y2O cannot be recommended.

Examples of dyes include C,1, Direct Red 1, C.
, 1, tie left let 4. C, 1, Assured Red 1
．． C, 1, Beige Tsukred 1. C, 1, Modern Red 30, C, 1, Direct Blue 1, C
, 1, Direct Blue 2. C, 1, acid blue 9
．． C:, 1. Acid blue 15. C,1, Basic Blue 3, C,I.

There are basic blue 5, C,1, modern blue, etc.

Pigments include Naphthol Yellow S, Non the Yellow G, Permanent Yellow NCG, Permanent Orange GTR, Hirazolone Orange, Benzidine Orange G, Permanentlet 4R, '7 Otsching Red Calcium Salt, Brilliant Carmiso 3B, Fast Violet. B, methyl violet lake, phthalocyanine blue.

There are First Sky Blue, Indance Blue-BC, etc.

Preferably, the pigments are disazo yellow, insoluble azo, and copper phthalocyanine, and the dyes are basic dyes and oil-soluble dyes.

Particularly preferably C,1, Pigment Yellow 17°C,
T, Pigment Yellow 15, C, 1, Pigment Yellow 13. C,! , Pigment Yellow 14,
C, 1, Pigment Yellow 12. C, 1, Pigment Red 5. C.I.

Pigment Red 3, C,1, Pigment Red 2
゜C,1, Pigment Red 6, C,1, Pigment Red 7, C,1, Pigment Blue 15, c,
, r, Pigment Blue 16 or having 2 to 2 substituents on the phthalocyanine skeleton having the structural formula (1) shown below.
These include triple-substituted copper phthalocyanine pigments.

(Left below) R, R': Alkylene group having 1 to 5 carbon atoms, however, X1 to
Except when all ×4 are −H.

Structural formula (1) As the dye, C,1, Solvent Red 49. C,I
.

Solvent Red 52. C, 1, Solvent Red 10
9.G. ■, Paysic Red 12, C, 1, Paysic Red 1. C, 1, Paysic Red 3b, etc.

The content of yellow toner, which is sensitive to the transparency of OHP films, is 10% of the binder resin.
12 parts by weight or less, preferably 0 parts by weight
．． 5 to 7 parts by weight is desirable.

If the amount is 12 parts by weight or more, the reproducibility of green and red, which are mixed colors of yellow, and human skin color in images is poor.

For other magenta and cyan color toners,
The amount is desirably 15 parts by weight or less, more preferably 0.1 to 9 parts by weight, based on 100 parts by weight of the binder resin.

It is also preferable that a charge control agent is added to the toner according to the present invention in order to stabilize the negative charge characteristics. In this case, a colorless or light-colored negative charge control agent that does not affect the color tone of the toner is preferable.

As the carrier used in the present invention, for example, surface-oxidized or unoxidized metals such as iron, nickel, copper, zinc, cobalt, manganese, chromium, rare earths, alloys or oxides thereof, and ferrites can be used. Moreover, there are no special restrictions on the manufacturing method.

Further, a system in which the surface of the carrier is coated with a resin or the like is particularly preferred in the above-mentioned J/B development method. As a method for this, any conventionally known method can be applied, such as a method in which a coating material such as a resin is dissolved or suspended in a solvent and applied and adhered to the carrier, or a method in which a powder is simply mixed.

Substances that adhere to the carrier surface vary depending on the toner material, but examples include polytetrafluoroethylene and monochlorotrifluoroethylene polymers.

Polyvinylidene fluoride 7 silicone resin, polyester resin, metal complex of ditertiary butylsalicylic acid,
Styrene resin, acrylic resin.

It is appropriate to use polyacid, polyvinyl butyral, nigrosine, aminoacrylate-1 resin, basic dye and its lake, fine silica powder, fine alumina powder, etc. singly or in combination, but the invention is not necessarily limited thereto.

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

It is preferred that these carriers have an average particle size of 20 to 100 g, preferably 25 to 70 g, more preferably 25 to 65 g.

A particularly preferred embodiment is a ternary ferrite of Cu-Zn-Fe, whose surface is coated with a combination of resins such as fluororesin and styrene resin, such as polyvinylidene fluoride and styrene-methyl methacrylate resin; Fluoroethylene and styrene-methyl methacrylate resin, fluorine-based copolymer and styrene-based copolymer;
etc. 90:10 to 20:80, preferably 70:30
A mixture with a ratio of ~30 near 0, 0.01~
Examples include coated ferrite carriers coated with 5% by weight, preferably 0.1-1% by weight, and having carrier particles of 250 mesh bath or 350 mesh ion having the above average particle size of 70 weight % or more. Examples of the fluorocarbon copolymer include vinylidene fluoride-tetrafluoroethylene copolymer (10:90 to 90:10), and examples of the styrene copolymer include styrene-2-ethylhexyl acrylate (20:80). ~80:20),
An example is styrene-2-ethylhexyne acrylate-methyl methacrylate (20-60:5-30:10-50).

The coated ferrite carrier has a sharp particle size distribution, provides favorable triboelectric charging properties for the toner of the present invention, and has the effect of improving electrophotographic characteristics.

When preparing a two-component developer by mixing with the toner according to the present invention, the mixing ratio is 5% as the toner concentration in the developer.
．． Good results are usually obtained from 0% to 15% by weight, preferably from 6% to 13% by weight. If the toner concentration is less than 5.0% by weight, the image density will be low and it will not be practical.
If it exceeds 15% by weight, fogging and in-flight scattering will increase.
Shortens the useful life of the developer.

As the fluidity improver used in the present invention, any fluidity improver may be used as long as it can increase fluidity by comparing before and after addition by adding it to the colorant-containing resin particles.

For example, fluororesin powders, such as vinylidene fluoride fine powder, polytetrafluoroethylene fine powder, etc.; or fatty acid metal salts, such as zinc stearate, calcium stearate, lead stearate, etc.; or metal oxides, such as zinc oxide powder; Alternatively, there are finely powdered silica, that is, wet-processed silica, dry-processed silica, and treated silica that is surface-treated with a silane coupling agent, a titanium coupling agent, silicone oil, etc.

A preferred flow improver is a fine powder produced by vapor phase oxidation of a silicon halide compound, which is called dry process silica or fumed silica.
It is manufactured by a conventionally known technique.

As a city version product, Tarano Scoo 500 (Talco Company)
, AERO3IL R-972 (Japan Aerosil Co., Ltd.).

The amount added to the colorant-containing resin particles is 1
0.01 to 10 parts by weight, preferably 0.1 to 51 parts by weight. If it is less than 0.01 part by weight, it will not be effective in improving fluidity, and if it is more than 10 parts by weight, it will promote fogging, smearing of characters, and scattering inside the machine.

Hereinafter, the present invention will be explained in detail with reference to Examples.

(Production example of polyester binder-1) Put 5.0 cups of polyoxypropylene (2,5)-2,2-bis(4-hydroxyphenyl)propane into four flasks, stirrer, condenser, thermometer, gas Set the inlet pipe and place it inside the mantle heater.

After purging the inside of the reaction vessel with nitrogen gas, the contents were reduced to 50-60%
At the point when the temperature was at °C, terephthalic acid 3, Omoi
', 012 alkenyl group-substituted succinic acid (C
+6H3o04) 1.5mo[, trimellidic acid 0.35
add moj).

This mixture system was heated to 210° C. and stirred. While removing the reaction water, the reaction was monitored by measuring the acid value every hour to check the reading of the reaction after about 5 hours had elapsed. Acid value is about 10
．． When the temperature reaches 0, the reaction is cooled to room temperature.

(Production example of polyester binder-2) Polyoxypropylene (2,5)-2,
3.4 cops of 2-bis(4-hydroxyphenyl)propane and polyoxyethylene(2,2)-2,2-bis(
4-Hydroxyphenyl)propane 1.7ioj? was placed in a flask, purged with nitrogen, and heated to 50°C.

To this, 2.3 moff of terephthalic acid and 2.3 moff of succinic acid substituted with an alkyl group of CI2. Omoj), trimellidic acid Q
, [imol were added, and the mixture was heated to 210° C. and stirred to react, and after the reaction was completed, it was cooled to room temperature.

(Production Example-3 of Polyester Binder) According to the same method as Production Example 1, polyoxypropylene (2,5)-2
, 2-bis(4-hydroxyphenyl)propane 4.8
＋＊of! , 0.2 mo of glycerin, & are placed in a flask, and the mixture is replaced with nitrogen and heated at 50°C. This includes 1.2 cups of terephthalic acid and 1.0 cups of glutaric acid! , Succinyl substituted with C8 alkenyl group ('$2.5raof!
, pyromellitic acid 0.3 aol! are added, and the mixture is heated to 210°C and stirred to react. After the reaction is completed, it is cooled to room temperature.

(Production example of polyester binder-4) According to the same method as production example 1, polyoxypropylene (2,5)-2
, 2-bis(4-hydroxyphenyl)propane 5.4
Place the glass in a flask, replace with nitrogen, and heat to 50°C.

Fumaric acid 4.8■OI in this! are added, and the mixture is heated to 210° C. and stirred to react. After the reaction is completed, it is cooled to room temperature.

Example 1 All parts are by weight.

For 100 parts by weight of the polyester resin of Production Example-1,
The coloring agent and dispersion improver in the following prescribed amounts are premixed using a shell mixer, melt-kneaded using a twin-screw extrusion kneader, and after cooling, coarsely pulverized using a hammer mill to approximately 1 to 2 m², and then air-mixed. 40 with a jet-type pulverizer
It was pulverized to a particle size of less than gm. Furthermore, the obtained finely pulverized product was classified and selected so that the volume average diameter in the particle size distribution was 4 to 15, and 100 parts of the classified product was mixed with fine silica powder treated with hexamethyldisilazane as a flow improver. 0
．． A cyan color toner was prepared by adding 5 parts of external additives.

Further, 8 to 12 parts by weight of this color toner is coated with about 0.35% by weight of vinylidene fluoride polymer and styrene-methyl methacrylate (copolymerization weight ratio B 5:35) at a weight ratio of 40:80. -Zn-Fe
Ferrite carrier (average particle size 48 mm; 250 mesh pass 350 mesh 79% by weight; true density '-5
g/c+++3) were mixed in a total amount of 100 parts by weight to prepare a developer. The developer concentration was 10%.

A copying test was conducted using a color electrophotographic apparatus having an OPC photosensitive drum shown in FIG. At this time, the fixing device 10
The fixing roller used in
It had a two-layer structure including a silicone resin layer with a thickness of 0 μm. The pressure roller used was 3cm HTV silicone rubber.

In addition, the developer of the present invention is made into a constant amount of developer by a developer regulating blade on the developing sleeve, and the J/B development method is used in the opposing portion of the photosensitive drum l having a negatively charged electrostatic latent image. A negatively charged toner is transferred onto a photosensitive drum using a reversal development method. In this example, the distance between the sleeve and the photosensitive drum in the development area was set to 450 gm.

Initial images obtained using this method were bright with good color saturation.

In addition, when this toner is sandwiched between two slide glass plates and heat is applied from the top and bottom to form a toner thin film, which is observed with an optical microscope (hereinafter referred to as the slide glass method), minute amounts of coloring agent are detected. It was found that the particles were uniformly dispersed.

Furthermore, even after printing 20,000 copies, a cyan image that faithfully reproduced the original without fogging was obtained. Further, transport within the copying machine and developer concentration detection were also good, and stable image density was obtained. Even after repeated copying of 20,000 sheets, no offset occurred to the fixing roller.

A magenta image was obtained using the above prescription in the same manner as in Example 1. The resulting image was a bright magenta color with high image density. Next, a durability test was conducted and the result was 5.0.
Even after 10,000 copies, there was no toner offset or wrapping around the fixing roller, and the images were good and free of roughness.

Example 3 A test was carried out in the same manner as in Example 1, except that the polyester binder of Production Example 3 was used, and the colorant was C, 1, Pigment Yellow 17.3.5 fi mini.

Even after 40,000 yen, there was no offset to the fixing roller, and the dispersibility by the slide glass method was extremely uniform.

A black toner was obtained using the same recipe as in Example 1 except for the above recipe. Further, using the cyan, magenta, and yellow color toners obtained in Examples 1 to 3, full-color copying was performed using the color electrophotographic apparatus shown in FIG. 1 in the transfer order of magenta, cyan, yellow, and black. The fixing roller at this time has a two-layer structure: an LTV silicone rubber layer with a thickness of 1.5 layers on the core metal, and a silicone resin layer with a thickness of 30 layers on the surface layer, and the pressure roller 1. h
It has a thin layer of 101 L or less of fluororesin on the HTV silicone rubber of m.

Even after 70,000 full-color copies were made, color copies with excellent color saturation remained unchanged from the initial image. In the case of full-color copying, there are many overlapping parts of four colors on the image, and the load on the fixing roller in terms of offset and durability is much greater than in the case of single-color copying.
In this test, even after 70,000 copies, the offset resistance of the fixing roller was almost unchanged from the initial state.

A developer was prepared and tested in the same manner as in Example 1 using the above formulation, but the resulting image was desaturated and had poor color reproducibility. According to the slide glass method, a number of colorant species were observed to aggregate in the toner, resulting in poor dispersibility.

In addition, due to the decrease in triboelectric charging ability during durability, 0.5
After 10,000 sheets, there was severe scattering inside the plane, and under low temperature and low humidity conditions, there was a significant charge-up with the carrier, and the image density was quite low, at less than 0.8 using a Macbeth reflection densitometer.

Comparative Example 2 In Example 1, the binder was changed to styrene-butyl methacrylate copolymer, and two formulations were used, with and without 3,5-ditertiarybutylaluminum salicylate, and images were produced in the same manner as in Example 1. Obtained.

As for the dispersibility measured by the slide glass method, many aggregates were observed regardless of the presence or absence of the compound, and the colorant was poorly dispersed. The cyan image had low saturation and lacked clarity.

Comparative Example 3 The fixing roller was made of 4.7 mm HTV silicone rubber,
Using a pressure roller made of 1.5+sm LTV silicone rubber coated with fluorine latex and repeating full-color copying in the same manner as in Example 4, offset occurred after only 4.5,000 copies, making it suitable for practical use. It became impossible.

Furthermore, the fixing roller was subject to thermal deterioration, and the roller material was peeling off from the core metal.

At a set temperature of about 160° C., which is below the heat resistance limit of HTV silicone rubber, the fixed image was a dull full-color image with insufficient fixation, reduced saturation, and poor gloss.

For this reason, the repeated copying durability test was conducted at a set temperature of 210°C so as to obtain almost practical images.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view schematically showing a color electrophotographic copying machine to which the color toner of the present invention is applied.

Claims (3)

[Claims] (1) Add etherified diphenol component to 4 of the total monomer amount.
0 to 60 mol%, 10 to 40 mol% of the total monomer amount of divalent carboxylic acid substituted with a C_6 to C_1_6 hydrocarbon group or its derivative component, trivalent or higher polycarboxylic acid or/and polyols, Or, it contains at least 1 to 20 mol% of the total monomer amount of derivative components thereof, and has an apparent melt viscosity of 10^5 to 2 x 10^6 poise and 2 x 10^ at 100°C and 110°C, respectively.
A color toner characterized in that the binder resin is a polyester resin having an endothermic peak temperature of 55 to 70° C. in DSC. (2) The color toner according to claim 1, containing 0.2 to 10 parts by weight of an organometallic complex containing a metal having an atomic number of 12 to 14 or 24 to 30 based on the binder resin. (3) In color copying, in which an electrostatic latent image obtained by color separation exposure of a document is developed with primary color toners, each toner image is superimposed and transferred onto transfer paper, and then fixed by a heated roller, the etherified diphenol component is used. 4 of the total monomer amount
0 to 60 mol%, 10 to 40 mol% of the total monomer amount of divalent carboxylic acid substituted with a C_6 to C_1_6 hydrocarbon group or its derivative component, trivalent or higher polycarboxylic acid or/and polyols, or derivative components thereof at least 1 to 20 mol% of the total monomer amount, and the apparent melt viscosity at 100°C and 110°C is 10^5 to 2 x 10^6 poise and 2 x 1 poise, respectively.
Using a color toner with a polyester resin as a binder resin, which has an endothermic peak temperature of 55 to 70°C in DSC, the color toner has a rubber-like elastic layer on a core metal. A color toner fixing method characterized by using a heat roller fixing device comprising a fixing roller having an anti-offset layer on its surface layer and a pressure roller having a rubber-like elastic layer on a core metal.