JPS5814149A - Toner - Google Patents

Abstract

PURPOSE:To obtain a toner of uniform magnetic characteristics by incorporating the parts constituted respectively of hydrocarbon monomers having conjugated diene bonds and vinyl type hydrocarbon monomers respectively at specific ratios based on the weight of a binder resin, and specifying the gel content of the binder resin at prescribed %. CONSTITUTION:A copolymer of hydrocarbon monomers having conjugated diene bonds is incorporated as a binder resin in a toner. Here, the parts constituted of the hydrocarbon monomers having conjugated diene bonds are contained at 2- 40wt% (more preferably 5-30wt%) based on the weight of the binder resin, and the parts constituted of vinyl hydrocarbon monomers at >=85wt% (more preferably >=90wt%) based on the weight of the binder resin, and the gel content of the binder resin is specified at 0.01-60% (more preferably 1-50%), whereby the good toner of uniform magnetic characteristics is obtained. It is preferable that the copolymerizing component of the hydrocarbon monomers having conjugated diene bonds is a styrene hydrocarbon monomer.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a toner for developing an electrostatic latent image or a magnetic latent image, and more particularly to a toner suitable for constant deposition on a roller.

Conventionally, as an electrophotographic method, U.S. Patent M2,297,69
A number of methods are known, such as those disclosed in Japanese Patent Publication No. 42-23910 and Japanese Patent Publication No. 43-24748, but generally a photoconductive substance is used and electrical conductivity is applied to the photoreceptor by various means. A latent image is formed, then the latent image is developed using toner, and if necessary, the toner image is transferred to a transfer material such as paper, and then the copy is fixed by heat, pressure, solvent vapor, etc. It's something you get.

Various magnetic recording methods are also known in which a magnetic latent image is formed and developed with magnetic toner.

In these methods, various methods and devices have been developed for the step of fixing the toner image on paper or the like. Currently, the most common method is the so-called hot roll fixing method, which applies heat and pressure at the same time.This method fixes the toner image onto the image-receiving sheet by bringing the image-receiving sheet carrying the toner image into contact with a heated roller. It's a method. However, when such a fixing method is used, problems such as so-called offset occur with conventional toner. Offset is an undesirable phenomenon in which a portion of the toner image carried on the image receiving sheet is transferred to the roller surface.

As described in Japanese Patent Publication No. 51-23354, such an offset phenomenon tends to occur when a low molecular weight resin is used. Therefore, as described in the same publication, it may be possible to prevent the offset phenomenon by using a crosslinked resin, but the present inventors have investigated that simply creating a crosslinked resin does not necessarily result in good results. I found out that it wasn't.

The roller that comes into contact with the toner image usually has at least a surface layer formed of silicone rubber or fluororesin, which has good releasability, but silicone is added to the optical surface to prevent offset and to prevent fatigue on the roller surface. There is also a method of applying a mold release oil such as oil. However, the method of applying oil has problems such as the provision of an oil application system which complicates the fixing device and the evaporation of the oil causing discomfort to the user. Therefore, it is not preferable to try to prevent offset by coating with oil; rather, it is currently desired to develop a toner with good offset resistance over a wide fixing temperature range.

Furthermore, with conventional toners, after the toner image support passes between the fixing rollers, means such as separation claws for separating the toner image support from the fixing roller tend to become contaminated due to multiple copying. Ta. If the separating means such as a separating claw is contaminated with toner, the ability to separate the toner image support from the fixing roller will be significantly reduced, which may cause a jam 9, which is undesirable.

Of course, in addition to fixing properties, toners also need to be excellent in anti-blocking properties, development properties, transferability, cleaning properties, etc., but conventional toners must have the following defects: had one or more.

That is, many toners that are easily melted by heating tend to cake or aggregate during storage or in a copying machine. Many toners have their triboelectric and rheological properties eroded by changes in environmental humidity. In addition, with many toners, the density of the resulting image decreases due to mutual deterioration of the toner, carrier particles, and photosensitive plate due to collisions between the toner particles and carrier particles due to repeated development through continuous use and their contact with the photosensitive plate surface. or increase the background density, reducing the quality of the copy. Furthermore, with many toners, if you try to increase the density of the copied image by increasing the amount of toner that adheres to the surface of the photosensitive plate that has the latent image,
Normally, the background density increases and a so-called fog phenomenon occurs.

Furthermore, as copying machines have become widespread in recent years, the number of cases in which copying machines are used in harsher environments has increased. Particularly when the copy is used under conditions of high temperature and extremely high humidity, the image density of the copy is significantly reduced, making it unusable.

Therefore, there is a need for a toner that has excellent various toner properties 9 and is suitable for the hot roller constant deposition method.

Therefore, it is an object of the present invention to provide a toner having excellent physical and chemical properties that overcomes the above-mentioned toner deficiencies.

SUMMARY OF THE INVENTION An object of the present invention is to provide a toner for constant wear on a hot roller, which has good fixing properties and particularly good anti-offset properties.

Furthermore, it is an object of the present invention that the toner image support has fixed n-9
- It is an object of the present invention to provide a toner that is less likely to contaminate a means such as a separating claw for separating a toner image support from a fixing roller after passing through a fixing roller.

A further object of the present invention is to provide a toner that has good chargeability and always exhibits stable chargeability during use, and provides a clear and capricious image.

Furthermore, the object of the present invention is to have excellent fluidity, not cause agglomeration,
An object of the present invention is to provide a toner that also has excellent impact resistance.

A further object of the present invention is to provide a toner in which the image density of copies hardly decreases even under high-temperature and ultra-high-temperature environments.

A further object of the present invention is to provide a toner with less deposits on the toner holding member or the surface of the photoreceptor.

A further object of the present invention is to provide a magnetic toner that exhibits good and uniform magnetism when used as a magnetic developer.

The feature is that in a toner containing a copolymer of a hydrocarbon monomer having a conjugated diene bond as a binder resin, the portion composed of the hydrocarbon monomer having a conjugated diene bond is 40% by weight (
The portion composed of the vinyl hydrocarbon monomer is preferably 85% by weight or more (preferably 90% by weight or more, particularly preferably 90% by weight or more) of the binder resin. The gel content of the binder resin is 0.01 to 60% (preferably 1 to 50%, particularly preferably 11 to 40%).

In a further preferred embodiment, the copolymerization component of the hydrocarbon monomer having a conjugated diene bond is a styrene hydrocarbon monomer, and the copolymer has a portion composed of the hydrocarbon monomer having a conjugated diene bond. 2 to 40% by weight (preferably 5 to 50% by weight, particularly preferably 7 to 50% by weight)
20% by weight). Alternatively, the copolymer has a gel content of 0.01 to 60% (preferably 1 to 50%, particularly preferably 11 to 40%), and the polymer is contained in the binder resin in an amount of 90% by weight or more. (preferably 95 layers or more).

In the present invention, gel content is defined by a value measured as follows. That is, the binder resin is weighed as a fixed weight (Wig) sample, the toluene-soluble components in the binder resin are removed using an extraction means such as a Soxhlet extractor, and the remaining sample is removed without being extracted. After drying, weigh (W2g). Gel content is W2/Wl
Calculated as x 100 (chi).

The reason why the binder resin has a gel content of 0.01 to 60 inches is because if it is less than 0.01%, the offset resistance will decrease, and if it exceeds 60 inches, the fixing performance will decrease.

Further, the toner-1 of the present invention using the above copolymer has a melt index of 0.01 to 20 g/10 m1n.
It is preferable that it is 0.1 to 10 g/10 m1n. If it is less than 0.01 g/10 min, the toner adhesion point tends to be too high, and 20 g/l 0
This is because if it is more than min, the offset resistance will be insufficient.

Here, the test conditions for the melt index are a temperature of 125℃,
Flow test method for thermoplastic plastics according to Japanese Industrial Standards JIS K7 with a load of 10 kg and a filling amount of 5 to 8 g.
Measurements were carried out by manual cutting method using the apparatus described in No. 210.

The hydrocarbon monomer used in the present invention is a monomer consisting essentially of carbon and hydrogen, and the styrenic hydrocarbon monomer includes styrene and its substituted substances, such as styrene and vinyltoluene. Hydrocarbon monomers having a conjugated diene bond include butadiene, imprene, piperylene, and the like. Further, vinyl hydrocarbon monomers include vinylnaphthalene, ethylene, propylene, butylene, divinylbenzene, divinylnaphthalene, and the like, in addition to the above-mentioned styrene hydrocarbon monomers and hydrocarbon monomers having a conjugated diene bond.

If the content of the portion composed of a hydrocarbon monomer having a conjugated diene bond in the binder resin is less than 2% by weight, the fixing performance will decrease, and if it exceeds 40% by weight, the toner will be damaged. This is because the blocking resistance of . The reason why the content of the vinyl hydrocarbon monomer is 85% by weight or more is that if the content is less than 85% by weight, the developing properties will be poor especially under high temperature and ultrahigh humidity.

Other copolymerizable monomers for the polymer used in the present invention include, for example, p-chlorostyrene.

Acrylic acid, methyl acrylate, methyl acrylate ethacrylate, ethyl methacrylate, butyl methacrylate,
Monocarboxylic acids or substitutes thereof having double bonds such as octyl methacrylate, acrylonitrile, methacrylonitrile, acrylamide, etc.; for example, maleic acid.

Dicarboxylic acids having double bonds such as butyl maleate, methyl maleate, maleate, dimethyl phosphate, etc., and substituted products thereof; for example, vinyl chloride.

Vinyl esters such as vinyl acetate, vinyl benzoate, etc.; Vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, etc.; Vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, etc. , N-vinyl-pyrrolidone and the like may be used alone or in combination of two or more.

As the crosslinking agent, compounds having two or more polymerizable double bonds are mainly used, such as aromatic divinyl compounds such as divinylbenzene, divinylnaphthalene, etc., such as ethylene glycol diacrylate, ethylene glycol diacrylate dimethacrylate, etc. , L3butylene dimethacrylate, etc.; divinyl compounds such as divinyl aniline, divinyl ether, divinyl sulfide, divinyl sulfone, etc. and compounds having 3 or more vinyl groups, singly or as a mixture used. The preferred amount used is 0. O2N20 wt%.

Further, in the present invention, it is preferable that the weight average molecular weight of the crosslinked copolymer is adjusted to about ioo, ooo to 1,000,000, and known molecular weight regulators can be used for this purpose. Examples include mercaptans such as lauryl mercaptan, phenyl mercaptan, butyl mercaptan, and dodecyl mercaptan; and halogenated carbons such as carbon tetrachloride and carbon tetrabromide. The preferred amount used is 0 to 20 wt based on the monomer.

The polymer of the present invention can be produced by emulsion polymerization or solution polymerization.

It is synthesized by well-known methods such as suspension polymerization and bulk polymerization.

For example, it is manufactured as follows.

[Example of production of copolymer used in the present invention]

Styrene 861! , Phtadiene 14II, divinylbenzene 0.25 g, fatty acid sodium 5 g, and water desalted with an ion exchange resin 200 ml were mixed and placed in an autoclave which is a polymerization vessel. Thereafter, 3.5.9, K, S, 0.2 g of n-dodecyl mercaptan was added and emulsion polymerization was carried out at 50° C. for 15 hours to obtain a styrene-butadiene-divinylbenzene copolymer.

The gel content of this copolymer was 14%. Additionally, other resins may be mixed into the toner of the present invention. Monopolymers of styrene and its substituted products, such as polystyrene, poly p-chlorostyrene, and polyvinyltoluene; e.g., styrene-p-chlorostyrene copolymer, styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene - Vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-methyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer Coalescence, styrene-methacrylic acid ether copolymer, styrene-butyl methacrylate copolymer, styrene-alpha chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-
Styrenic copolymers such as vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-acrylonitrile-indene copolymer; silicone resin,
Polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, polyurethane, polyamide, epoxy resin, polyvinyl butyral, rosin, modified rosin, terpene resin, phenolic resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin , chlorinated paraffin, paraffin wax, etc. can be used alone or in combination.

The binder resin of the toner of the present invention contains 85% by weight (85% by weight) of the aforementioned vinyl hydrocarbon monomer.
The content should preferably be 90% by weight or more, particularly preferably 95% by weight. In this regard, the toner of the present invention can provide good images even in particularly high-temperature and ultra-high-temperature environments. Conventionally used toners mainly used a copolymer of styrene and acrylic acid ester or methacrylic acid ester as a binder resin, and contained an acrylic component 'f: 20% or more of violet. The development characteristics under environmental conditions were not favorable. The toner of the present invention is significantly different from conventional toners in this respect, and furthermore, the binder resin contains 2 to 40% of the hydrocarbon monomer component having a conjugated diene bond.
weight percent (preferably 5 to 30 weight percent,
Particularly preferably, the binder resin contains 0.01 to 60 inches (preferably 1 to 50 inches),
By having a gel content (especially preferably 11 to 40%), it has a low fixing point and excellent anti-offset properties in a hot roll fixing system.

Furthermore, the toner of the present invention exhibits much superior fixing properties compared to conventional toners when it is used as a positively charged waxy toner for developing a negative latent image. The present inventor found that, for example, in a toner using a styrene-acrylic polymer, the constant M characteristics of the toner are significantly different when the same toner is made into a positively charged toner using different carriers and when it is made into a negatively charged toner. I found something different. In other words, when a positive latent image is developed thickly as a load* toner, transferred onto plain paper, and fixed with a heat roller (fc), offset resistance is excellent to some extent, but as a positively charged toner, a negative latent image is developed. When the image is developed, transferred onto plain paper, and fixed with a heated roller, the offset resistance is poor. Although the cause of this is still unknown, the present inventors suggest the following. In other words, normally, a fluororesin-coated roller and a silicone rubber roller with good releasability are used in the hot roll fixing method, but when ordinary transfer paper passes between these rollers, it is frictionally charged. Positively charged.

On the other hand, both rollers are negatively charged with respect to the transfer paper. If the toner on the transfer paper is positively charged, the toner is electrically likely to be transferred to the fixing roller. On the other hand, if the toner on the transfer paper is negatively charged, it will be difficult to transfer to the fixing roller. It is thought that the difference in the direction in which the electric force acts on the toner results in a difference in offset resistance. On the other hand, even when the toner of the present invention is a positively charged toner, it has excellent offset resistance because the binder resin contains 2 to 40 weight percent of the hydrocarbon monomer component having a conjugated diene bond, and This is thought to be due to the fact that the toner contains 85 percent by weight or more of the vinyl hydrocarbon monomer component, and its releasability from the fixing roller is superior to toners made of conventional styrene-acrylic copolymers.

In order to make the toner of the present invention a positively charged toner, the polymer used in the toner of the present invention is a polymer synthesized from monomers containing the following monomers, where R1: hydrogen, lower alkyl group, R2: lower Alkylene group, R, jR4: hydrogen, lower alkyl group, allyl group, R: hydrogen, lower alkyl group, nigrosine, substituted quaternary ammonium salt, etc., in an amount of 0.1 to 20% by weight relative to the binder resin. It may also be included.

Further, in order to make the toner of the present invention a negatively charged toner, it may contain a metal complex of a monoazo dye (as described in Japanese Patent Publication No. 41-20153, etc.).

All known coloring substances can be used in the present invention, such as carbon black, iron black, graphite, and nigrosine.

Ultramarine, Phthalocyanine Blue, Hansa Yellow.

Dyes and pigments such as benzidine yellow, quinacridone, and various lake pigments can be used.

For the toner of the present invention, an ethylene-based olefin polymer having a melt viscosity at 140°C of 10 to 10' CPS, preferably 50 to 101 CPS, such as polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, is used. ethylene-ethyl acrylate copolymer.

By containing an extremely small amount of an ionomer having a polyethylene skeleton, 0.1 to 10% by weight (preferably 0.2 to 5% by weight) based on the weight of the toner, fixing characteristics and developing characteristics can be improved. Improved.

Furthermore, the developing powder of the present invention is mixed with carrier particles such as iron powder, glass beads, nickel powder, and 7-elide powder, if necessary, and used as a developer for electrical latent images. Further, fine colloidal silica powder may be added for the purpose of improving the free-flowing property of the powder, and an abrasive such as cerium oxide may be added to prevent toner from sticking.

In addition, in the case of making magnetic toner, the magnetic powder is ferromagnetic elements and alloys and compounds containing them, such as magnetite, hematite, iron of ferrite, cobalt,
It is sufficient to add substances conventionally known as magnetic materials such as alloys and compounds of nickel and manganese, and other ferromagnetic alloys.
．． It may be added as a fine powder of 0.01 to 5 microns, preferably 0.05 to 1 micron, in an amount of about 1 to 60% by weight, preferably 15 to 45% by weight of the weight of the toner.

Furthermore, the developing method applied to the toner of the present invention is not particularly limited, but includes the magnetic brush method described in U.S. Pat. No. 2,874,063, and U.S. Pat.
The cascade development method described in the specification of Japanese Patent Application Laid-open No. 5
4-42141, a method using an insulating magnetic toner described in JP-A-55-18656, and U.S. Patent No. 3
, 909,258, a method using a conductive toner, a method using a high-resistance magnetic toner, and the like.

Alternatively, it may be one that develops a magnetic latent image.

[Example 1] Styrene-butadiene-divinylbenzene copolymer (copolymerization weight ratio 86:14:0.4, gel content a o
%) 100xts / 72 parts by weight of magnetic powder, 50 parts by weight of magnetic powder, melt viscosity at 140°C is 1200PS
2 parts by weight of polyethylene were ground and mixed in a ball mill,
Melt and knead using a roll mill. After cooling, the mixture is coarsely ground using a 1 mm mill. Then, it is finely pulverized using a supersonic jet pulverizer. The obtained powder was classified using an air classifier, and particles of approximately 1 to 35 μm were collected and used as toner. The gel content of the binder resin of the toner is 29 cm. This toner 100
One part by weight of silica fine particles produced by a wet method was added to the part by weight to prepare a developer.

A negative latent image is also formed on the zinc oxide photoreceptor.

This latent image is transferred to a silk sleeve 3 with a diameter of 50 mm as shown in FIG.
Sleeve surface magnetic velocity density 700 Gauss.

The distance between the ear cutting blade 4 and the sleeve surface is 0.25.The dragon sleeve rotating magnet fixed (sleeve circumferential speed is the same as that of the drum L, but the direction is opposite) type developer is set so that the distance between the insulating layer surface and the sleeve surface is 0.25. Set the developing sleeve to -200V DC bias and 1.3KHz 1.3
The image is developed using the developer 6 by applying an alternating current bias of KV, and then the powder image is transferred while irradiating a direct current corona of 17 kV from the back side of the transfer paper. Fixing was performed using a fixing device (NP-200J, manufactured by Canon). A clear image without fogging was obtained. Further, no offset phenomenon was observed and the fixing temperature range was wide. A durability test of 10,000 sheets was conducted, and the image and offset resistance were good. In addition, there was almost no dirt on the separation nail. In addition, images were produced under a high temperature and ultra-high humidity environment (35°C, 90%), but there was very little decrease in image density.
A good image was obtained.

[Comparative Example 1] Using a styrene-butyl acrylate-divinylbenzene copolymer (copolymerization weight ratio 70:30:0.45.Gelcontin 32%) and not using a styrene-butadiene-divinylbenzene copolymer. When the test was carried out in the same manner as in Example 1 except for this, a clear image without capri was obtained, but when a durability test of 10,000 sheets was carried out, the image was smeared by offset toner. In addition, the separation claws were also extremely dirty and jammed frequently. In addition, although images were produced under a high temperature and extremely high humidity environment, the image density decreased.

[Example 2] 100 parts by weight of styrene-butadiene-divinylbenzene copolymer (copolymerization weight ratio 88:12:0.3, gel content 22%), 60 parts by weight of magnetic powder, melt viscosity at 140°C of 1200 PS 2 parts by weight of polyethylene, metal complex dye (trade name).

A toner was prepared from 2 parts by weight of Savon 7 Asto Black B (manufactured by BASF). The gel content of the binder resin of the toner is 22 inches. 0.3 parts by weight of hydrophobic colloidal silica was added to 100 parts by weight of this toner to prepare a developer. Using this developer, a commercially available copying machine (product name, NP
-200J, images were taken using a Canon camera.

A good image was obtained. A durability test of 10,000 sheets was conducted, and the image and offset resistance were good, and there was almost no staining on the separation claw. Furthermore, when images were produced at 35° C. and 90° below, there was very little decrease in image density and clear images were obtained.

[Comparative Example 2] Styrene-butadiene-divinylbenzene 70:30
:0.25. The procedure was carried out in almost the same manner as in Example 2 except that Gelcontin (17%) was used.
The image density decreased significantly below 90 inches. During a durability test of 10,000 sheets, the separation claw became contaminated and jams occurred several times.

[Example 3] Instead of the styrene-butadiene-divinylbenzene copolymer of Example 1, a styrene-butadiene-acrylonitrile-divinylbenzene copolymer (copolymerization weight ratio 80
: 16 : 4 : 0.35) Gel content 27%)
The procedure was carried out in substantially the same manner as in Example 1, except for using , and good results were obtained. The gel content of the binder resin of the toner is 26 inches.

[Example 4] Instead of the styrene-butadiene-divinylbenzene copolymer of Example 1, a styrene-isoprene-butyl methacrylate-divinylbenzene copolymer (copolymerization weight ratio 84
The same procedure as in Example 1 was carried out except that 38%) of Gelcontin: 12; 4: 0.45° Gel Contin) was used, and a clear image was obtained and the offset resistance was also good.

The gel content of the binder resin of the toner is 37 cm.

[Example 5] Instead of the styrene-butadiene-divinylbenzene copolymer of Example 1, a styrene-isoprene-1,3-butylene dimethacrylate copolymer (copolymerization weight ratio 84:16) was used.
:0.4. Good results were obtained when the procedure was carried out in substantially the same manner as in Example 1, except that a gel content of 30 cm) was used. The gel content of the toner binder resin is 2
It is 9%.

[Example 6] Instead of the styrene-butadiene-divinylbenzene copolymer of Example 1, a styrene-butadiene-butyl acrylate-divinylbenzene copolymer (copolymerization weight ratio 77:
When the same procedure as in Example 1 was carried out except for using 15:8:0.5° gel content (35%), a clear image was obtained and the offset resistance was also good.

The gel content of the binder resin of the toner is 34%.

[Example 7] A styrene-butadiene-divinylbenzene copolymer (copolymerization ratio 70:30:0.6, gel content 46%) was used instead of the styrene-butadiene-divinylbenzene copolymer of Example 1. Except for this, the same procedure as in Example 1 was carried out, and good results were obtained. The gel content of the binder resin of the toner is 45 inches.

[Example 8] Styrene-butadiene-butyl acrylate-divinylbenzene copolymer (copolymerization x-m ratio 73:
14:13:0.15°) 0%) 15 times sweetened, styrene-dimethylaminoethyl methacrylate copolymer (
Copolymerization weight ratio 90:10, Gelcontin) (1)
Good results were obtained when the procedure was carried out in substantially the same manner as in Example 1, except that 5 parts by weight was used and nigrosine was not used. The gel content of the binder resin of the toner is 7%.

[Example 9] Example 1 (100 parts by weight of polymer D, nigrosine base 2
Part of N, melt viscosity at 140°C is approximately a o, o o
A toner was prepared in much the same manner as in Example 1 from i parts of 0 cps polyethylene 4 parts and 6 parts by weight of carbon black. Toner binder resin Ge 400 (manufactured by Nippon Tetsuko Co., Ltd.) 8
8 parts by weight were mixed to prepare a developer. Using this developer, reversal development was performed using a commercially available copying machine (trade name: NP-5000, manufactured by Canon). Clear images were obtained and offset resistance was also good.

[Example 1O] Instead of the styrene-butadiene-divinylbenzene copolymer of Example 1, 87 weight of styrene-butazine-divinylbenzene copolymer (copolymerization weight ratio 79:21:0.65, gel content 58%) The same procedure as in Example 1 was conducted except that 13 parts by weight of styrene-butyl acrylate copolymer (copolymerization weight ratio 70:30, gel content 0 parts) was used, and good results were obtained. Ta. The gel content of the binder resin of the toner is 49%.

The fixing properties, anti-offset properties, and image densities at room temperature and humidity and at high temperature and ultra-high humidity on each side are shown below.

A: Fixability B: Offset resistance However, the dramatic offset property and fixing property were measured as follows.

For offset resistance, a pair of heat fixing rollers (Teflon rollers on the image surface) were used, and the paper speed was 110/8.
Use ee to set the fixing roller surface temperature to a predetermined temperature and pass the peta image through. For offset, rub the toner adhering to the roller with white paper (product name: JK Kwai 150. did.

Regarding fixability, rub the image with the above paper 10 times, and if there is no change in the image and the paper is hardly stained, it is rated as ○.
A case where no change was observed in the image but the paper was slightly stained was rated Δ, and a case where a change was observed in the image and the paper was stained was rated X.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view of a developing device using a magnetic developer. 1...Photosensitive drum. 2... Magnet roll. 3...Cylindrical sleeve. 4...Blade. 6...Magnetic developer. Applicant Canon Co., Ltd.

Claims (1)

[Claims] In a toner containing a copolymer of a hydrocarbon monomer having a conjugated diene bond as a binder resin, the portion composed of the hydrocarbon monomer having a conjugated diene bond accounts for 2 to 40% by weight of the binder resin, and the vinyl A toner characterized in that a portion composed of a hydrocarbon monomer has a weight ratio of 85% or more of a binder resin, and a gel content of the binder resin is 0.01 to 60%.