JPS5812580B2 - Toner for developing electrostatic images - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a toner for developing electrostatic images in electrophotography, electrostatic recording, electrostatic printing, and the like.

Methods for developing electrostatic images include the liquid development method, which uses a developer in which various pigments and dyes are finely dispersed in an insulating organic liquid, the cascade method, the bristle brush method, the magnetic brush method, and the impression method. There is a spot dry development method using a fine powder developer called a toner, which is a natural or synthetic resin containing a colorant such as carbon black dispersed therein, such as the powder cloud method. This relates to the toner used.

After developing an electrostatic charge image using toner, fixing is performed. Generally, fixing involves directly fusing the toner image obtained by development onto a photoconductive photoreceptor or electrostatic recording medium that carries the electrostatic charge image. Alternatively, the toner image obtained by development may be transferred from a photoconductive photoreceptor or an electrostatic recording medium onto a transfer sheet such as paper, and then fused onto the transfer sheet. It will be done.

At this time, the toner image is fused either by contact with solvent vapor or by heating, and the heating methods generally include a non-contact heating method using an electric furnace and a compression heating method using a heated roller.

The pressure heating method using a heating roller performs fixing by passing the toner image on the sheet to be fixed while being in pressure contact with the surface of a heating port roller whose surface is made of a material that has releasability for toner. This method is generally called the heating roller constant adhesion method, but since the surface of the heating roller and the toner image surface of the fixing sheet come into pressure contact, it is difficult to fuse the toner image onto the fixing sheet. Since it has extremely good thermal efficiency and can perform fixing quickly, it is extremely effective particularly in transfer-type electrophotographic copying machines intended for high-speed copying.

For example, the thermal efficiency of an ordinary electric furnace type fixing device is generally about 10 to 40%, and the thermal efficiency of a side radiation type fixing device is about 20%, which is relatively low, whereas the thermal efficiency of a roller constant fixing device is said to be about 80%. .

Needless to say, if the thermal efficiency is to be further increased, it is necessary to further reduce the thickness of the coating film on the surface of the roller made of a material having mold releasability.

By the way, in the fixed heating roller fixing method, since the surface of the fixing roller and the toner image come into pressure contact in a heated and molten state, a part of the toner image adheres to the surface of the fixing roller and is transferred, and this is transferred onto the next sheet to be fixed. This transfer occurs again, causing so-called offset development, which often causes stains on the sheet to be fixed.

Therefore, preventing toner from adhering to the roller surface is considered to be one of the essential requirements in the fixed heating roller deposition method.

Conventionally, in order to prevent toner from adhering to the surface of the fixing roller, for example, the roller surface was made of a material with excellent release properties against toner, such as fluorine-based resin, and the surface was further coated with offset prevention material such as silicone oil. It is practiced to supply a liquid to coat the surface of the roller with a thin film of liquid.

Although this method is extremely effective in preventing toner offset, it generates an odor due to heating of the offset prevention liquid and requires a device to supply the offset prevention liquid. However, since the mechanism of the copying machine becomes complex and high precision is required to obtain stable results, the copying machine becomes expensive.

However, if offset prevention liquid is not supplied, toner adheres to the surface of the fixing roller and an offset phenomenon occurs, so despite these drawbacks, it is currently necessary to supply offset prevention liquid. It is.

An object of the present invention is to provide an electrostatic charge image that can be efficiently and consistently fixed to a heated roller without causing toner offset even when a fixing roller that does not supply an offset prevention liquid to the surface of the fixing roller is used. The purpose of the present invention is to provide developing toner.

The present inventors have discovered that a toner for developing electrostatic images containing a colorant, a styrenic resin, and a low molecular weight reflex copolymer achieves the above object.

By using the toner for developing an electrostatic image according to the present invention, even when no offset prevention liquid is supplied to the surface of the fixing roller, it is possible to efficiently and properly adhere to the heating roller without causing an offset phenomenon. Therefore, the mechanism of the fixing device can be simplified and, for example, the accuracy of high-speed copying machines incorporating such a fixing device can be improved.
Stability and reliability can be improved, and costs can also be reduced.

Therefore, it has the advantage of making the design of an ultra-high speed copying machine extremely easy.

Any suitable pigment or dye can be used as a colorant in the toner according to the invention.

For example, carbon black, nigrosine dye, aniline blue, calco oil blue, chrome yellow, ultramarine blue, DuPont oil red, quinoline yellow, methylene blue chloride, phthalocyanine blue, malachite green oxalate, lamp black, rose bengal and mixtures thereof. is used,
These need to be contained in the toner in an amount sufficient to color the toner so that a visible image can be formed by development.

In the toner according to the present invention, a styrene resin is used as a resin component.

The styrenic resin may be a styrene homopolymer,
It may also be a copolymer of styrene and other vinyl monomers.

Monomers for forming these copolymers include P-chlorostyrene, vinylnaphthalene, ethylenically unsaturated monoolefins such as ethylene, propylene, butylene, isobutylene, vinyl chloride, vinyl propionate, bromide, etc. Vinyl esters such as vinyl, vinyl fluoride, vinyl acetate, vinyl benzoate, vinyl butyrate, such as methyl acrylate, isobutyl acrylate, ethyl acrylate, n-butyl acrylate, dodecyl acrylate, n-octyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, methyl alpha-chloroacrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, tert-butyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate , ferul methacrylate, tridecyl methacrylate, stearyl methacrylate, cyclohexyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxybutyric methacrylate, dimethylaminoethyl methacrylate, diethylamino methacrylate Esters of α-methylene aliphatic monocarboxylic acids such as ethyl, glycidyl methacrylate, tetrahydrofurfuryl methacrylate, acrylonitrile, methacrylonitrile, acrylamide, such as vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, etc. vinyl ethers such as vinyl methyl ketone, vinyl hexyl ketone, methyl isopropenyl ketone, and N-vinyl compounds such as N-vinylpyrrole, N-vinylcarbazole, N-vinylidol ζN-vinylcapyrolidene, etc. One or more of these can be copolymerized with a styrene monomer.

Suitable styrenic resins have a weight average molecular weight of about 30,000 or more and have a styrene content of at least about 25% by weight based on the total weight of the styrenic resin.
It is preferable that

A thermoplastic resin system in which a styrene resin is mixed with other resins can also be used as the resin component of the toner according to the present invention.

Other resins that can be mixed with styrenic resins include:
Vinylnaphthalene, such as vinyl chloride, vinyl bromide,
Vinyl esters such as vinyl fluoride, vinyl acetate, vinyl propionate, vinyl benzoate, vinyl butyrate, such as methyl acrylate, isobutyl acrylate, ethyl acrylate, n-butyl acrylate, dodecyl acrylate, n-acrylate -Octyl, AcIJ/L' acid 2
-Chloroethyl, phenyl acrylate, methyl α-chloroacrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, tert-butyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, methacrylate Phenyl methacrylate, tridecyl methacrylate, stearyl methacrylate, cyclohexyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxybutyryl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, methacrylate glycidyl acrylate,
Esters of α-methylene aliphatic monocarboxylic acids such as methacrylic acid tetrahydride and furfuryl, acrylonitrile, methacrylic nitrile, acrylamide, vinyl ethers such as vinyl methyl ether, vinyl ethyl ether and vinyl isobutyl ether, such as vinyl methyl ketone, Polymerization of monomers such as vinyl ketones such as vinylhexyl ketone and methyl isopropenyl ketone, and N-vinyl compounds such as N-vinylpyrrole, N-vinylcarhasol, N-vinylindole, and N-vinylpyrrolidene. homopolymers or copolymers obtained by copolymerizing two or more of these monomers, such as rosin-modified phenol-formalin resins, oil-modified epoxy resins, polyurethane resins, polyamide resins, polyacetal resins, cellulose resins, polyethers, etc. There are non-vinyl thermoplastic resins such as resins.

When these resins are used in combination with a styrenic resin, the two should be mixed in such an amount that the styrene component is present at least about 25% by weight, based on the total weight of the resulting resin. It is preferable to do so.

This is because the releasability of the toner from the fixing roller is closely related to the amount of styrene component present, and as the styrene component is reduced, the releasability of the toner from the fixing roller tends to decrease.

Further, as a resin for toner, one of the physical properties preferable for constant adhesion to a roller is viscoelasticity in a rubber-like region at the fusing temperature of the toner.

This viscoelasticity is mainly based on the structure and molecular weight distribution of the toner resin.

The effective creep modulus of the rubbery region when the roller is fixed without adding an anti-offset liquid to the roller surface is suitably 105 to 109 dyne/ffl.

If the creep modulus is less than this value, there will be a portion that is fixed onto the transfer paper during melting and a portion that is torn off by the fixing roller and remains, and an offset phenomenon is likely to occur.

To prevent the offset phenomenon, it is sufficient to add a large amount of a substance that imparts release properties to the toner, but even if only the offset phenomenon can be prevented, other properties required for the toner, such as fluidity and image quality, etc. It is undesirable because it damages the

Furthermore, if the creep modulus value is above the above range, the degree of fixation is poor and the image tends to peel off from the transfer paper.

Of course, in this case, it would be better to further raise the fixing temperature, but this would exceed the heat resistance limit of the roller material, which is not preferable.

That is, even if the low molecular weight olefin copolymer used in the toner according to the present invention is contained in a toner whose main component is a styrene resin having a creep modulus value,
Further, it is possible to provide a good toner for developing electrostatic images that does not cause offset development even when a toner containing a styrene resin having a creep modulus value outside this creep modulus value as a main component.

The low molecular weight olefin copolymer used in the toner of the present invention is an olefin copolymer containing only olefin as a monomer component or an olefin copolymer containing a monomer other than olefin as a monomer component. It has a relatively low molecular weight.

Examples of olefins as monomer components include ethylene, propylene, butene-1, pentene-1, and hexene-1.
1, heptene-1, octene-1, nonene-1, decene-1 or their homologues with different positions of the unsaturated bond, or for example 3-methyl-1-butene, 3-methyl-2-pentene, 3-probyl All kinds of olefins such as -5-methyl-2-hexene and the like having an argyl group introduced therein as a branched chain are included.

In addition, examples of monomers other than olefin that form a copolymer with olefin include vinyl methyl ether, vinyl-n-phthyl ether,
Vinyl ethers such as vinyl phenyl ether, vinyl esters such as vinyl acetate and vinyl butyrate, haloolefins such as vinyl fluoride, vinylidene fluoride, tetrafluoroethylene, vinyl chloride, vinylidene chloride, tetrafluoroethylene, etc. , such as methyl acrylate, ethyl acrylate, n-butyl acrylate, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, stearyl methacrylate, N,N-
Acrylic esters or methacrylic esters such as dimethylaminoethyl methacrylate and t-butylaminoethyl methacrylate; acrylic type derivatives such as acrylonitrile and N,N-dimethylacrylamide; such as acrylic acid, methacrylic acid, maleic acid; Examples include various acids, organic acids such as fumaric acid and itaconic acid, diethyl fumarate, and β-pinene.

The low molecular weight olefin copolymer according to the present invention is an olefin copolymer consisting only of olefins containing at least two or more of the above-mentioned olefins as monomer components, such as ethylene-propylene copolymers, ethylene-butene copolymers, Ethylene-pentene copolymer, propylene-butene copolymer, propylene-pentene copolymer, ethylene-3-methyl-1-butene copolymer, ethylene-propylene-butene copolymer, etc., or at least one of the above-mentioned olefins. Olefin copolymers containing as monomer components at least one monomer other than olefin, such as ethylene-vinyl acetate copolymer, ethylene-vinyl methyl ether copolymer, ethylene-vinyl Chloride copolymer, ethylene-methyl acrylate copolymer, ethylene-methyl methacrylate copolymer, ethylene-acrylic acid copolymer, propylene-vinyl acetate copolymer, propylene-vinylethyl ether copolymer, propylene-ethyl Acrylate copolymer, propylene-methacrylic acid copolymer, butene-vinyl methyl ether copolymer, butene-methyl methacrylate copolymer, pentene-vinyl acetate copolymer, hexene-vinyl butyrate copolymer, ethylene -Propylene-vinyl acetate copolymers, ethylene-vinyl acetate-vinyl methyl ether copolymers, etc., with a weight average molecular weight of about 10,000 or less, particularly those with a weight average molecular weight of about 3,000 to 8,000 are effective. are effective in the present invention.

Generally, those having a large molecular weight have low compatibility and dispersibility with styrenic resins, and are therefore not desirable for use in the present invention.

Among the low molecular weight olefin copolymers according to the present invention, those containing monomers other than olefin as monomer components preferably contain as much olefin component as possible in the copolymer.

This is because, in general, as the content of the olefin component decreases, the mold releasability decreases, and characteristics such as toner fluidity and image quality tend to deteriorate.

Therefore, it is desirable that the content of the olefin component in the copolymer be as high as possible, and in particular, a copolymer containing about 50 mol% or more of the olefin component is effectively used in the present invention.

The low molecular weight olefin copolymer according to the present invention can be produced by appropriately combining the above-mentioned olefin monomers and monomers other than olefin, oxygen, a peroxide, a polymerization initiator such as azonitrile, a Ziegler-Natsuta catalyst, a Phillips It can be easily obtained by polymerization according to a conventional method in the presence of a catalyst such as a catalyst such as a Friedel-Crafts catalyst.

The copolymer obtained at this time depends on the type and amount of each monomer used, the reaction conditions, and the degree of polymerization, copolymerization composition ratio, molecular weight distribution, etc.
Crystallinity, glass transition point, etc. can be adjusted.

In addition, as a polymerization method, graft polymerization method, block polymerization method, radiation polymerization method, etc. can also be used.

The amount of the low molecular weight olefin copolymer contained in the toner varies depending on the resin components of the toner, the types of colorants and toner additives, and their usage amounts, but is generally 1 to 30 parts by weight per 100 parts by weight of the resin components of the toner. parts, preferably 3 to 20 parts by weight.

In order to incorporate the low molecular weight olefin copolymer into the toner, it may be added during pre-mixing of the resin component, colorant and various toner additives prior to the kneading step.

Note that dyes and pigments as colorants are most commonly incorporated into the toner by melt-kneading, but in some cases they may also be adsorbed onto the surface of the toner.

The low molecular weight olefin copolymer according to the present invention exhibits a low viscosity liquid state when heated, so when a toner containing this comes into contact with a heated fixing roller, the low molecular weight olefin copolymer in the toner liquefies. It is thought that the toner is released on the surface of the toner and coats the surface of the fixing roller, and its releasability reduces the adhesive force at the interface, preventing the fused toner from adhering to the surface of the fixing roller and causing the offset phenomenon. .

Such a release effect is observed not only in a fixing roller whose surface is made of a releasable material, but also when a fixing roller whose surface is made of metal, which is generally considered to have no releasable properties, is used.

Therefore, if the toner according to the present invention is used, it is possible to prevent the toner offset phenomenon even without using a fixing roller whose surface is made of a releasable material, which is extremely advantageous in terms of device design.

The effect of adding the low molecular weight olefin copolymer according to the present invention to the toner is, in addition to improving the release properties as described above, by improving the dispersibility of colorants such as nigrosine and other additives contained in the toner. Uniform charge controllability of particles,
It also has the effect of improving the performance as a developer.

The toner according to the present invention may further contain various compounds having a releasing effect other than the low molecular weight olefin copolymer in combination with the low molecular weight olefin copolymer.

These compounds include, for example, cadmium, barium, lead, iron, nickel, cobalt, copper, strontium, calcium or magnesium salts of stearic acid, zinc, manganese and iron oleic acids. salts, cobalt, copper, lead or magnesium salts, zinc, cobalt, copper, magnesium, aluminum or calcium salts of palmitic acid, zinc, cobalt or calcium salts of linoleic acid, ricinoleic acid Fatty acid metal salts such as zinc salt or cadmium salt, copper salt of caprylic acid, lead salt of caproic acid, higher fatty acids having 38 or more carbon atoms, natural or synthetic paraffins, bis fatty acid amides such as ethylene bisstearamide, Examples include fatty acid esters or partially saponified components thereof, and these compounds may be contained alone or in combination of two or more.

The amount of these compounds added to the toner is generally about 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight, per 100 parts by weight of the resin component of the toner. This further improves the compatibility of the low molecular weight olefin copolymer with the resin component, and also further improves the dispersibility of other toner additives such as colorants and charge control agents.

Further, when the resin component has relatively brittle properties, it is possible to prevent excessive pulverization in the pulverization process during toner production.

Furthermore, the stability of the toner is increased, and the triboelectricity does not change even during long-term use, so that the life of the toner can be significantly extended.

Note that various other toner additives can be added to the toner according to the present invention as necessary.

The toner image formed on the fixing sheet using the toner according to the present invention is efficient and good without causing the toner offset phenomenon even when a fixing roller that does not supply offset prevention liquid to the surface of the fixing roller is used. It is possible to perform constant fixing of the heating roller.

The surface of the fixing roller can be coated with Teflon (
DuPont), Fluon (ICI), Kelu F (
Fluorine resin such as 3M) or KE-130OR
Items with a smooth surface made of room temperature vulcanized silicone rubber such as TV (manufactured by Shin-Etsu Chemical Co., Ltd.) and PRX-305 (manufactured by Toray Industries, Inc.), or those with a metal surface such as hard chrome in some cases, are effective. used.

Next, the present invention will be illustrated by examples, but the embodiments of the present invention are not limited thereto.

In the examples, the number of parts is expressed by weight unless otherwise specified.

Example 1 100 parts by weight of Picolastic D-150 (styrenic resin manufactured by Esso Petrochemical Co., Ltd.), 5 parts of Peerless 155 (manufactured by Columbia Carbon Co., Ltd.), 3 parts of Nigrosine Base EX (manufactured by Orient Chemical Co., Ltd.), and ethylene-propylene copolymer. Polymer (copolymerization molar ratio 20:80, weight average molecular weight 6000)
The mixture was mixed with 8 parts, subjected to a ball mill for about 24 hours, kneaded using a heated roll, cooled and pulverized to prepare a toner having an average particle size of about 12 to 15 microns, which was used as a sample.

A toner was prepared as a comparative sample in exactly the same manner as described above, except that no ethylene-propylene copolymer was added.

Four parts of each of these toners were mixed with 96 parts of iron powder carrier having an average particle size of about 50 to 80 microns to form two developers, and these developers were used to form by conventional electrophotographic methods. After developing the electrostatic charge image, the toner image is transferred onto transfer paper, and a fixing roller whose surface is made of FEP (manufactured by DuPont, a copolymer of tetrafluoroethylene and hexafluoropropylene) is used to transfer the toner image to 165 to 175 mm.
The toner image was fused and fixed by pressure contact at .degree.

After each fusing operation to determine whether the fused toner image is then transferred to the surface of the fusing roller and offset development occurs.

A transfer paper without a toner image was brought into pressure contact with a fixing roller under the same conditions as above, and stains caused by toner offset on the transfer paper were observed.

As a result, when the comparison sample toner was used, significant staining due to toner offset was observed on the transfer paper, but when the sample toner was used, no staining occurred on the transfer paper, and the toner offset phenomenon was observed. It was recognized that this does not occur.

This result was exactly the same even when this fixing operation was repeated.

Example 2 80 parts of Picolastic D-125 (manufactured by Esso Petrochemical Co., Ltd., styrene resin), 20 parts of Eslec BL-1 (manufactured by Sekisui Chemical Co., Ltd., polyvinyltyral resin), and Peerless 1
55, 3 parts of Oril Black BW (manufactured by Orient Chemical Co., Ltd.), and 10 parts of ethylene-propylene copolymer (copolymerization molar ratio 50:50, weight average molecular weight 4000) were mixed to produce Example 1. A toner was prepared in the same manner and used as a sample.

A toner was prepared as a comparative sample in exactly the same manner as described above, except that no ethylene-propylene copolymer was added.

Using these two types of toners, the same operations as in Example 1 were performed except that a fixing roller whose surface was made of Teflon (manufactured by DuPont, polytetrafluoroethylene) was used, and the offset properties of each toner were determined. Examined.

As a result, it was found that a significant toner offset phenomenon occurred when the comparative sample toner was used.
It was found that no toner offset phenomenon occurred when the sample toner was used.

Example 3 100 parts of a copolymer of about 90 parts of styrene and about 10 parts of dimethylaminoethyl methacrylate with a softening point of 120°C and Diablack SH (manufactured by Mitsubishi Chemical Corporation,
Carbon black) and 5 parts of propylene-pentene-1 copolymer (copolymerization molar ratio 70:30, weight average molecular weight 5000) were mixed and treated in the same manner as in Example 1 to prepare a toner. did.

A toner was prepared as a comparative sample in exactly the same manner as described above, except that the propylene-pentene-1 copolymer was not added.

These two types of toner are used to make the surface of the fixing roller.
The same operations as in Example 1 were performed except that a toner whose surface was formed with E-1800RTV (manufactured by Shin-Etsu Chemical Co., Ltd., silicone rubber) was used, and the offset properties of each toner were examined.

As a result, it was found that a significant toner offset phenomenon occurred when the comparative sample toner was used, but it was found that no toner offset phenomenon occurred when the sample toner was used.

Example 4 100 parts of a copolymer of about 80 parts of styrene and about 20 parts of 3-chloro-2-hydroxypropyl methacrylate having a softening point of 140°C according to the ring and ball method, 18 parts of Diablack SH, Oil black BW 5 parts and
AC polyethylene 400 (manufactured by Allied Chemical Co., Ltd., ethylene-vinyl acetate copolymer, copolymerization molar ratio 86:
14, weight average molecular weight 3500) were mixed and treated in the same manner as in Example 1 to prepare a toner, which was used as a sample.

A toner was prepared as a comparative sample in exactly the same manner as described above except that AC polyethylene 400 was not added.

These two types of toner were used, a fixing roller with a Teflon surface was used, and the fusing temperature was set to 1.
The same operation as in Example 1 was performed except that the temperature was 70 to 180°C, and the offset properties of each toner were examined.

As a result, it was found that a significant toner offset phenomenon occurred when the comparative sample toner was used, but it was found that no toner offset phenomenon occurred when the sample toner was used.

Example 5 100 parts of a copolymer of about 85 parts of styrene and about 15 parts of stearyl methacrylate having a softening point of 125° C. according to the ring and ball method, 5 parts of Peerless 155, 15 parts of Nigrosine Base EX, Ethylene-acrylic acid copolymer (copolymerization ratio 70:30, weight average molecular weight 5000) 1
0 parts and processed in the same manner as in Example 1 to prepare a toner and use it as a sample.

A toner was prepared as a comparative sample in exactly the same manner as described above, except that no ethylene-acrylic acid copolymer was added.

These two types of toner were used, a fixing roller with a Teflon surface was used, and the fusing temperature was set to 1.
The same operation as in Example 1 was performed except that the temperature was 60 to 170°C, and the offset properties of each toner were examined.

As a result, it was found that when the comparative sample toner was used, a significant toner offset phenomenon occurred, but when the sample toner was used, no offset phenomenon was observed.

Example 6 100 parts of a copolymer of about 70 parts of styrene and about 30 parts of butyl methacrylate, 5 parts of Diablack SH, part of Oil Black BWB, and an ethylene-butene-1 copolymer (copolymerization ratio of 80 :20, weight average molecular weight 7500
) were mixed with 5 parts and processed in the same manner as in Example 1 to prepare a toner and use it as a sample.

A toner was prepared as a comparative sample in exactly the same manner as above except that the ethylene-butene-1 copolymer was not added.

Using these two types of toner, the fusing temperature was set to 170 to 180.
The same operations as in Example 1 were performed except that the temperature was changed to .degree. C., and the offset properties of each toner were examined.

As a result, it was found that a significant toner offset phenomenon occurred when the comparative sample toner was used.
When the sample toner was used, it was found that no toner offset phenomenon occurred.

Example 7 100 parts of Picolastic D-150, part Diamond Black SHS, 5 parts of Oil Black BS (manufactured by Orient Chemical Co., Ltd.), 4007 parts of AC polyethylene, and 1 part of zinc stearate were mixed, and the same procedure as in Example 1 was carried out. The toner was processed and used as a sample.

A toner was prepared as Comparative Sample A in exactly the same manner as described above except that zinc stearate was not added.

Furthermore, a toner was prepared as Comparative Sample B in exactly the same manner as described above, except that zinc stearate and AC polyethylene 400 were not added.

The same operations as in Example 1 were performed using these three types of toner, and the offset properties of each toner were examined.

A fixing roller whose surface was made of Teflon was used, and the fusing temperature was 175 to 185°C.

As a result, it was found that a significant toner offset phenomenon occurred when Comparative Sample B toner was used, but when Comparative Sample A and Sample toner were used, no toner offset phenomenon occurred. It was approved not to do so.

Further, as a result of repeated use, it was found that the toner of the sample had a longer lifespan with no change in triboelectric charging properties over a long period of time than the toner of Comparative Sample A.

Example 8 100 parts of a copolymer of about 50 parts of styrene, about 30 parts of methyl methacrylate, and about 20 parts of butyl methacrylate, which has a softening point of 140° C. according to the ring and ball method, and Peerless 155 5 1 part, 5 parts of nigrosine base EX, and 8 parts of the ethylene-propylene copolymer used in Example 2.
1 part and 0.5 part of calcium stearate were mixed and treated in the same manner as in Example 1 to prepare a toner and use it as a sample.

A toner was prepared as Comparative Sample A in exactly the same manner as described above except that calcium stearate was not added.

Furthermore, a toner was prepared as Comparative Sample B in exactly the same manner as described above except that calcium stearate and ethylene-propylene copolymer were not added.

Using these three types of toner, the fusing temperature is 170 to 180.
The same operation as in Example 1 was performed except that the temperature was changed to 0.degree. C., and the offset properties of each toner were examined.

As a result, it was found that a significant toner offset phenomenon occurred when Comparative Sample B toner was used, but when Comparative Sample A and Sample toner were used, there was no toner offset phenomenon at all. It was confirmed that this does not occur.

Further, as a result of repeated use, it was found that the toner of the sample did not change its triboelectric charging properties over a long period of time and had a long life compared to the toner of Comparative Sample A.

Example 9 100 parts of a copolymer of about 70 parts of styrene and about 30 parts of butyl methacrylate and 5 parts of Diablack SH;
Oil black BWB part and 5 parts of propylene-vinylethyl ether copolymer (copolymerization ratio 85:15, weight average molecular weight 7800) were mixed and treated in the same manner as in Example 1 to prepare a toner and use it as a sample. .

A toner was prepared as a comparative sample in exactly the same manner as described above, except that the propylene-vinylethyl ether copolymer was not added.

Using these two types of toner, the fusing temperature was set to 170 to 180.
The same operation as in Example 1 was performed except that the temperature was changed to 0.degree. C., and the offset properties of each toner were examined.

As a result, it was found that a significant toner offset phenomenon occurred when the comparative sample toner was used.
When the sample toner was used, it was found that no toner offset phenomenon occurred.

Example 10 100 parts of a copolymer of about 50 parts of styrene, about 30 parts of methyl methacrylate, and about 20 parts of butyl methacrylate, which has a softening point of 140°C according to the ring and ball method, and Peerless 155 5 1 part, 5 parts of nigrosine base EX, and propylene-vinyl acetate copolymer (copolymerization ratio 8
0:20, weight average molecular weight 7000) and 0.5 part of calcium stearate were mixed and treated in the same manner as in Example 1 to prepare a toner and use it as a sample.

A toner was prepared as Comparative Sample A in exactly the same manner as described above except that calcium stearate was not added.

Furthermore, a toner was prepared as Comparative Sample B in exactly the same manner as above except that calcium stearate and propylene-vinyl acetate copolymer were not added.

Using these three types of toner, the fusing temperature is 170 to 180.
The same operation as in Example 1 was performed except that the temperature was changed to 0.degree. C., and the offset properties of each toner were examined.

As a result, it was found that a significant toner offset phenomenon occurred when Comparative Sample B toner was used, but when Comparative Sample A and Sample toner were used, there was no toner offset phenomenon at all. It was confirmed that this does not occur.

Further, as a result of repeated use, it was found that the toner of the sample did not change its triboelectric charging properties over a long period of time and had a long life compared to the toner of Comparative Sample A.

Claims (1)

[Claims] 1 Colorant, styrene resin, and toner resin component 1
A toner containing 1 part by weight or more and 30 parts by weight or less of a low-molecular-weight olefin copolymer based on 00 parts by weight, and having a composition in which the content of the olefin component in the copolymer is determined to be about 50 mol% or more. A toner for developing an electrostatic image, characterized in that it is used in combination with a heating roller fixing device.