JPS61130957A - Heat fixing type developing material - Google Patents

Abstract

PURPOSE:To provide a developing material which has a good release property from a heating roll at a high temp., offsets hardly in high-speed copying, has a smaller tendencty to aggregation and has the higher resistance to folding after fixing by incorporating a specific modified polyolefin wax, binder resin and coloring agent into said material. CONSTITUTION:The modified PO wax formed by grafting 2-30pts.wt. unsatd. carboxylate to 98-70pts.wt. polyolefin (PO) wax having 0.007-0.6dl/g intrinsic viscosity (100pts.wt.total of both), binder resin and coloring agent are incorporated into the developing material. The heat fixable developing material constituted in such a manner has the excellent release property from the heating roll, etc. even at a high temp. and therefore said material does not offset even if the fixing speed is increased by increasing the temp. of the heating roll. The material has the smaller tendency to aggregation, the excellent developing characteristic and the good resistance to folding after fixing.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a heat-fixing type electrophotographic developer (toner). More specifically, it relates to a toner that has excellent release properties during fixing, less agglomeration during storage and copying operations, less contamination of the photosensitive drum (good developability), and excellent bending resistance during fixing. It is.

[Conventional technology]

A developing material for electrophotography, so-called electrostatic toner (hereinafter simply referred to as toner), is an image forming material used in the next stage of charging and exposure in electrostatic electrophotography.
It is a charged fine powder in which black and pigments are dispersed. In general, electrostatic toners include dry two-component toners that are used with carriers such as iron powder or glass particles, wet toner dispersion systems that use organic solvents such as isoparaffin, and even dry toners that have magnetic fine powder dispersed within them. - Classified as component toner.

An image developed on a photosensitive plate with electrostatic toner is transferred to paper, and an image developed directly on paper coated with a photosensitive layer is fixed as is with heat or solvent vapor. Among these, fixing using a heated roller is preferable because it is a contact fixing method, has high thermal efficiency, can reliably fix images using a relatively low-temperature heat source, and can also be used for high-speed copying.

However, when fixing an image by contacting a heating body such as a heating roller, there is a risk that a so-called offset phenomenon may occur in which a portion of the electrostatic toner adheres to the heating body and is transferred to a subsequent image portion. Particularly in high-speed copying, raising the temperature of the heating element to increase the fixing effect and fixing speed results in the offset phenomenon becoming more likely to occur. For this reason, for example, when fixing an image formed using a component-based electrostatic toner using a heated roller, the offset phenomenon is eliminated by impregnating the roller surface with silicone oil or supplying silicone oil to the roller surface. However, this results in problems such as stains on the rolls.

On the other hand, thermoplastic resin, which is the main material of electrostatic toner,
Styrenic polymers such as low molecular weight polystyrene, ketone resins, maleic acid resins, coumaron resins, phenolic resins, epoxy resins, terpene resins, styrene (meth)
Acrylic ester copolymer, polyvinyl butyral,
Examples include polybutyl methacrylate, among others, low molecular weight styrene/(meth)acrylic acid ester copolymers have good charging properties, a suitable softening point (around 100°C), good fixing properties, and photoreceptors. It is the most commonly used material because of its characteristics such as easy cleaning, less contamination, less hygroscopicity, good miscibility with the colorant carbon black, and ease of crushing. However, as mentioned above, low molecular weight styrene/(meth)acrylic acid ester copolymers with such characteristics also tend to cause offset phenomenon in high-speed copying. Development of electric toner is desired.

In order to solve the above problems, we used polyolefin wax as a mold release agent in styrene polymer.

For example, the technology to be added is
No. 305, No. 57-52574, No. 58-58664, and Japanese Unexamined Patent Publication No. 58-59455. However, even with this technology, the compatibility between the polyolefin wax and the styrene-based FFI composite component is still insufficient, so not only is the polyolefin wax's performance as a mold release agent not fully demonstrated, but also Or, toner tends to aggregate during copying,
In addition, since wax is more likely to be released than toner, it can easily lead to contamination of photosensitive drums, etc.
There was also a drawback that the bending resistance of i was poor.

The inventors of the present invention have conducted various studies on the wax to be added as a release agent to the toner, and were able to obtain an excellent toner free from the above-mentioned drawbacks.

[Summary of the invention]

That is, the present invention has a limiting viscosity of 0.607 to 0.641.
2 to 30 MMWI of unsaturated carboxylic acid ester per 98 to 70 parts by weight of /g of polioless wax.
(total of both is 100 parts by weight) of a modified polyolefin wax (A), a binder resin (B), and a colorant (C). The purpose of the present invention is to provide a developing material for use in

[Raw material polyolefin wax]

The graft-modified polyolefin wax (A) used in the toner of the present invention is a modified polyolefin wax obtained by graft-modifying a specific polyolefin wax with an unsaturated carboxylic acid ester.

The polyolefin wax to be subjected to graft copolymerization must have an intrinsic viscosity (measured in a decalin solvent at 135°C) in the range of 0.07 to 0.6 dl/g, and must have an intrinsic viscosity of 0.07 to 0.6 dl/g. It is preferably in the range of 0.8 to 0.5 a/g. In this case, when the polyolefin wax has ethylene as the main polymerization unit, it is preferable to use one having an intrinsic viscosity in the range of 0.07 to 0.5. For those whose main polymerization unit is an α-olefin other than ethylene, those obtained by thermal decomposition are in the range of 0.07 to 0.6, and those obtained by direct polymerization of α-olefins are in the range of 0.
It is preferable to use one in the range of 0.09 to 0.6.

If the intrinsic viscosity of the polyolefin wax is less than 0.07, even if the graft-modified polyolefin wax obtained from the polyolefin wax is used as a raw material for a toner composition, the melt viscosity will be too low and a sufficient mold release effect will not be obtained. In addition, it is easy to cause toner aggregation and contamination of the photoreceptor.

Furthermore, if the intrinsic viscosity of the raw material polyolefin wax is greater than 0.6, even if a graft-modified polyolefin wax prepared from the polyolefin wax is similarly used as a toner raw material, it will lack compatibility with the styrene polymer described below. In addition, the melt viscosity is too high, and the mold release effect is not sufficient.

Here, the polyolefin wax includes ethylene, propylene, 1-butene, 1-hexene, 4-methyl-1
- Homopolymers of α-olefins such as pentene and 1-decene, or copolymers of two or more α-olefins, with an intrinsic viscosity within the above-mentioned range. for example,
Polyolefin wax obtained by thermal decomposition of high-pressure polyethylene, high-pressure polymerized polyolefin wax obtained by radical polymerization of ethylene at high pressure, medium-low pressure polymerization of ethylene or ethylene and the above α-olefin in the presence of a transition metal compound catalyst Polyolefin wax or ethylene/α-olefin copolymer wax, polypropylene wax, poly-1
Examples include -butene wax, poly-4-methyl-1-pentene wax, polypropylene/4-methyl-1-pentene copolymer wax, and hexene-1,4-methyl-1-pentene copolymer wax.

Note that the polyolefin wax referred to herein also includes oxides of polyolefin wax. The oxygen content in this case is usually within 10% by weight.

[Unsaturated carboxylic acid ester]

Specifically, the unsaturated carboxylic acid ester (al) used to synthesize the graft-modified polyolefin wax constituting the toner of the present invention.

Methyl acrylate, ethyl acrylate, n-acrylate
Butyl, isobutyl acrylate, propyl acrylate,
n-octyl acrylate, dodecyl acrylate, lauryl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, cyclohexyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, α-methyl chloroacrylate, 2-acrylate -hydroxyethyl,
Diethylaminoethyl acrylate, diethylene glycol ethoxylate acrylate, 2-ethoxy acrylate, 1,4-butanediol diacrylate, 2,2.
Acrylic acid esters such as 2-trifluoroethyl acrylate, 2-acryloyloxyethyl acid phosphate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, methacrylate n-octyl methacrylate, dodecyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, methacrylic acid Ethyl methacrylate such as 2-hydroxyethyl, glycidyl methacrylate, 2.2.2-trifluoroethyl methacrylate, 2-methacyloyloxyethyl acid phosphate, monoethyl maleate, diethyl maleate, monopropyl maleate , dipropyl maleate, monobutyl maleate, dibutyl maleate, di2-ethylhexyl maleate, monoethyl fumarate, diethyl fumarate, dibutyl fumarate, di2-ethylhexyl fumarate, monoethyl itaconate, diethyl itaconate , monobutyl itaconate, di-2-ethylhexyl itaconate, monoethyl citraconate, diethyl citraconate, dibutyl citraconate, di-2-ethylhexyl citraconate, and other unsaturated dibasic acid esters. I can do it.

Two or more of these can also be used simultaneously. child
Among them, those used in the examples described later are particularly preferred.

In addition to the above monomers, other vinyl heptamers (b
), for example, styrene, α-methylstyrene, vinyltoluene, acrylonitrile, N-methylolacrylamide, vinyl acetate, vinylpyrrolidone, vinylpyridine, vinylcarbazole, vinylbutyral, vinylacecool, acrylic acid, methacrylic acid, etc. are simultaneously grafted. It's okay. In particular, when a styrene resin such as styrene (meth)acrylate resin is used as the binder resin, it is preferable to simultaneously graft a styrene thread binder such as styrene or vinyltoluene.

[Properties of modified polyolefin wax, etc.] The grafting ratio of the unsaturated carboxylic acid ester (a) is in the range of 2 to 30 parts by weight to 98 to 70 parts by weight of the polyolefin wax separately described above (the total of both is 100 parts by weight). It is necessary that the amount is in the range of 3 to 25 parts by weight per 97 to 75 N parts of the polyolefin wax.

In addition, when simultaneously grafting other monomers (Tb) such as styrene and vinyltoluene, (al and (
The total grafting proportion with bl is preferably 3 to 50 parts by weight. Also, grafted (aJ and (b)
The weight ratio (b) can be arbitrarily selected depending on the compatibility with the binder resin such as styrene polymer, but the weight ratio (b)
/ (a) preferably does not exceed 2.

If the grafting ratio of the unsaturated carboxylic acid ester grafted onto the polyolefin wax is less than the lower limit of the above-mentioned essential range, the compatibility with binder resins such as styrene resins will be poor, and this will improve as the compatibility improves. The effects of mold releasability, agglomeration resistance, drum stain resistance, bending resistance, etc. will be reduced, and if the upper limit of the essential range is exceeded, the compatibility between the modified polyolefin wax and the binder resin will become too large. During fixing, it becomes difficult for the modified polyolefin wax in the toner to be liberated on the surface of the melt, and the effect as a release agent also becomes poor.

In addition, the graft-modified polyolefin wax used in the present invention not only has excellent compatibility with binder resins such as styrene polymers, but also has various additives such as pigments, dyes, charge control agents, and plasticizers. It also has excellent compatibility or affinity with agents. Therefore, it also has the effect of increasing the dispersibility in these binder resins, increasing the physical uniformity of the toner such as charge controllability, and improving the performance as a developer.

Intrinsic viscosity (η) of the graft-modified polyolefin wax constituting the toner of the present invention [135
Measured at °C] is usually O, OS or 0.8a/g
, preferably in the range of 0.08 to 0.5.

[Production method of modified polyolefin wax] The graft-modified polyolefin wax constituting the toner of the present invention can be produced by a conventionally known method. For example, a method is adopted in which the polyolefin wax and the unsaturated carboxylic acid ester are reacted under heating in a solution state or a molten state, where the reaction is carried out in the presence of a radical initiator if necessary. be able to.

The radical initiators used in the above reaction include organic peroxides, organic peresters, such as benzoyl peroxide, dichlorobenzoyl peroxide, dicumyl peroxide, di-tert-butyl peroxide, 2,5
-dimethyl-2,5-di(peroxide benzoate)
Hexyne-3,1,4-bis(tert-butylperoxyisopropyl)benzene, lauroyl peroxide, tert-butyl peracetate, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexyne-3,2 ,5-dimethyl-2,5-di(tert-
butylperoxy)hexane, tert-butylperphenylacetate, tert-7'tylperisobutyrate, tert-butylperu5ec-octoate, tert-butylperpivalate, cumylpervivalate and tart-butylperdiethyl acetate,
There are other azo compounds, such as azobis-isobutylnitrile, dimethylazoisobutyrate. Among these, dicumyl peroxide, di-tert-butyl peroxide, 2.5-butyl peroxide, 2.5-
Dimethyl-2,5-di(tert-butylperoxy)
Hexyne-3,2,5-dimethyl-2,5-dimethyl-
2,5-di(tert-butylperoxy)hexane,
Dialkyl peroxides such as 1,4-bis(tert-butylperoxyisopropyl)benzene are preferred. The temperature during the reaction is usually in the range of 130 to 350°C, preferably 135 to 300°C.

[Binder resin]

Examples of the binder (thermoplastic) resin (B) such as a styrene polymer used in the toner of the present invention include JP-A-50-2
A styrenic resin as described in No. 7546, that is, a polymer consisting only of styrene monomers or a copolymer of styrene monomers and other vinyl monomers, can be used as is. That is, monomers for forming the copolymer include p-chlorostyrene, vinylnaphthalene, ethylenically unsaturated monoolefins such as ethylene, propylene, butylene, and isobutylene, such as vinyl chloride, vinyl bromide, and vinyl fluoride. Vinyl halides such as vinyl acetate, vinyl propionate, vinyl henzoate, vinyl esters such as vinyl butyrate, such as methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, n-acrylate
of α-methylene aliphatic monocarboxylic acids such as octyl, dodecyl acrylate, 2-chloro-ethyl acrylate, phenyl acrylate, methyl α-chloroacrylate, methyl methacrylate, ethyl methacrylate, and butyl methacrylate. Esters, acrylonitrile, methacrylonitrile, acrylamide, vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, methyl isopropenyl ketone, such as N-vinylpyrrole , N-vinylcarbazole, N-vinylindole, N-vinylpyrrole, and the like, and one or more of these can be copolymerized with a styrene monomer. A suitable styrenic polymer has a molecular weight of about 2,000 or more, particularly preferably 3,000 to 3
It preferably has a number average molecular weight of 0.000 and has a styrene content of at least about 25% by weight, based on the total weight of the styrenic polymer.

Other thermoplastic resins include, for example, ketone resins, maleic acid resins, coumaron resins, phenolic resins, epoxy resins, terpene resins, polyvinyl butyral, polybutyl methacrylate, polyvinyl chloride, polyethylene,
Examples include polypropylene, polybutadiene, ethylene-vinyl acetate copolymer, and the like.

Among the above, styrenic polymers are preferred.

[Coloring 7FI] The coloring agent (C) used in the electrostatic toner of the present invention includes carbon black, fucrocyanine blue, aniline blue, alco oil blue, chrome yellow, ultramarine blue, quinoline yellow, lamp black, rose bengal, diazu yellow, It consists of one or more pigments or dyes such as rhodamine B lake, cardin 6B, and quinacridone derivatives. If necessary, azine-based nigrosine, insulin, ab-based,
Oil-soluble dyes such as anthraquinone-based, triphenylmethane-based, xanthine-based, and phthalocyanine-based dyes may be used in combination.

[Other Components] In addition to the above-mentioned components (A), (B), and (C), other components may be added to the toner of the present invention within a range that does not impair the effects of the present invention. For example, other toner additives such as charge control agents and plasticizers can be included. These addition amounts are arbitrary and appropriate amounts.

[Method for preparing toner of the present invention]

When the electrostatic toner of the present invention is used as a one-component electrostatic toner, the graft-modified polyolefin wax (
A), the binder resin (B) and the colorant (C) are mixed using a known method such as a ball mill or an attritor, then kneaded using a heated twin roll, heated kneader-1 extruder, etc., and cooled and solidified. , coarsely crushed using a hammer mill, crusher, etc., then jet mill, vibration mill, or ball mill by adding water.
The toner is finely pulverized using an attritor or the like, and the average particle size is about 5 to 35 μm, which is used as an electrostatic toner. - When using component-based electrostatic toner as a developing material, it is used in combination with a carrier. As the carrier, known carriers such as silica sand, glass beads, iron balls or powders of magnetic materials such as iron, nickel, and cobalt having a diameter of 200 to 700 μm can be used. - The amount of modified polyolefin wax (A) in the component-based electrostatic toner is:
It is preferably added in an amount of 1 to 20 parts by weight (2 to 10 parts by weight) per 100 parts by weight of the thermoplastic resin including the binder resin (B).

Further, when the electrostatic toner of the present invention is used as a one-component electrostatic toner, the above-mentioned three essential components (A), (B) and (
In addition to C), additives, other thermoplastic resins, and magnetic material powders that may be added as necessary can be prepared in the same manner as in preparing the one-component electrostatic toner. Also in this case, the amount of modified polyolefin wax (A) is 100 parts by weight of the binder thermoplastic resin (B),
It is added in an amount of 1 to 25 parts by weight, preferably 1 to 20 M parts. - As the magnetic material powder added to component-based electrostatic toner, fine magnetite powder of 1μ or less is usually used, but powders of metals such as cobalt, iron, nickel, alloys thereof, oxides, ferrite, and mixtures thereof, etc. can also be used. - The amount of each component in the component-based electrostatic toner is usually such that the total amount of the binder thermoplastic resin and the magnetic material is 100 parts by weight, and the magnetic material is blended at a ratio of 40 to 70 parts by weight.

If the amount of magnetic material is too large, the electrical resistance of the electrostatic toner decreases, the charge retention of the electrostatic toner deteriorates, and the image may be blurred. Furthermore, the softening point of the electrostatic toner may become high, making it difficult to properly fix the toner. On the other hand, if the amount of magnetic material is too small, the function as an electrostatic donor will be lost, the required charging ability will not be obtained, and the magnetic material will be easily scattered.

Further, a known charge control agent may be added to the one-component electrostatic toner or the two-component electrostatic toner, if necessary.

t"8"1"""4141°1001, it has excellent releasability from heating rolls, etc., not only at high temperatures but also at high temperatures, so even if the heating roll, etc. is heated to a high temperature and the fixing speed is increased, offset phenomenon is unlikely to occur. This makes it ideal for high-speed copying. It also has low aggregation, excellent development properties, and excellent bending resistance after fixing.

The effects of the present invention will be explained in more detail with reference to Examples below.

〔Example〕

Example 1 (Preparation of unsaturated carboxylic acid ester grafted polyolefin wax) Intrinsic viscosity [η] 0.2 polymerized with Ziegler type catalyst
3 dl/g polyolefin wax (homopolymer) (
All of the polyethylene waxes used in the following examples were polymerized using a Ziegler type catalyst. ) 5
00g into a 1.51 glass reactor and heated to 160℃
It was dissolved in Next, 105 g of 2-ethylhexyl methacrylate and 8.8 g of di-t-butyl peroxide (hereinafter abbreviated as DTBPO) were added and reacted by heating for 3 hours, and then degassed in a 10 mmHg vacuum for 1 hour in the molten state. It was treated to remove volatiles and then cooled. Next, 20 g of this material was dissolved in 200 ml of rose xylene, and the resulting solution was dissolved in methyl ethyl ketone at 60°C.
0 ml with stirring. The precipitated solid portion was further washed twice with 500 ml of methyl ethyl ketone and dried.

The content of 2-ethylhexyl methacrylate in the obtained solid portion was determined by 'H-NMR.

The amount of graft determined in this manner was 16.3 parts by weight based on 100 parts by weight of the 2-ethylhexyl methacrylate grafted polyethylene wax.

The 2-ethylhexyl methacrylate grafted polyethylene wax is designated as MW-1.

(Preparation of toner and copying test) Styrene/n-butyl methacrylate copolymer Hymer SBM-600 manufactured by Sanyo Chemical Industries) 85 parts by weight, MW
-14 parts by weight, 9 parts by weight of carbon black (Dia Black 5H manufactured by Mitsubishi Kasei Kogyo Co., Ltd.), and 2 parts by weight of alloy dye (Zapon Fast Black B manufactured by BASF) were mixed in a ball mill for 24 hours, and then kneaded with a hot roll. After cooling, the mixture was crushed and classified to produce an electrostatic toner having a size of 13 to 15 μm. Next, iron powder with an average particle size of 50 to 80 μm was mixed as a carrier in a ratio of 2 parts by weight of electrostatic toner to 100 parts by weight of carrier, developed on a selenium photoreceptor by a conventionally known electrophotographic method, and transferred onto transfer paper. The image was transferred and fixed by heating with a heating roll at 200°C. As a result, even after 5,000 copies, a copied image was obtained that was as clear as the initial image and was free from offset development and staining, and no staining of the heat roll or photosensitive drum was observed.

Example 2 In the same manner as in Example 1, 60 g of 2-ethylhexyl acrylate, 55 g of styrene, and DTBPOlo, Og were added to 500 g of polypropylene wax (homopolymer) with (η) of 0.14 polymerized with a Ziegler type catalyst. A styrene/2-ethylhexyl acrylate grafted polypropylene wax containing 10.3 parts by weight of the 2-ethylhexyl acrylate component and 8.9 parts by weight of the styrene component was obtained by heating and reacting at 170°C for 3 hours. (M
W-2) Next, 7 parts by weight of the MW-2 and Hymer SBM-60
A toner was prepared in the same manner as in Example 1 using 82 parts by weight of 0, 9 parts by weight of Diamond Black SH, and 2 parts by weight of Pomegranate Black, and a copying test was conducted. As a result, even after copying 10,000 times, a copied image was obtained that was as clear as the initial image and free of offset development, staining, etc., and no staining of the heat roll or photosensitive drum was observed.

Furthermore, a bending resistance test was conducted. The fixed black image area was repeatedly bent 500 times, and the degree of fixation before and after the bending was visually determined before and after peeling off the cellophane tape. As a result, it was found that the degree of fixation remained almost unchanged even after the bending test, and that the film had excellent bending resistance.

Example 3 Polymerization was carried out using a Ziegler type catalyst in the same manner as in Example 1 [η) 0.31d! / g, ethylene content 3.2m
Add 60 g of n-butyl methacrylate and 5,0 g of DTBPO to 500 g of o1% polypropylene wax,
A heating reaction was carried out at 70° C. for 3 hours to obtain n-butyl methacrylate grafted polypropylene wax (MW-3) containing 9.1 parts by weight of n-butyl methacrylate.

Next, instead of using MW-1 in Example 1, the MW-3
A toner was prepared in the same manner as in Example 1, except that a toner was used, and a copying test was conducted.

As a result, even after 5,000 copies, a copied image was obtained that was as clear as the initial image and free from any offset phenomenon or contamination, and no contamination of the heat roll or photosensitive drum was observed.

Furthermore, changes in toner fluidity with temperature were investigated.

The toner was placed on a petri dish, and its fluidity was visually determined. As a result, the fluidity of the product kept at 50° C. for 48 hours and the product kept at room temperature was almost the same, and it was found that the product had excellent fluidity even in a high-temperature environment.

Example 4 Polyethylene wax 5 with [η) 0.11 g/a and propylene content of 1.6 mo1% was prepared in the same manner as in Example 1.
00g, add 70g of diethyl itaconate, 70g of vinyltoluene, and 5g of DTBPOll, and heat at 160°C.
The reaction was carried out by heating for 3 hours, and the amount of diethyl itaconate grafted was ii, the amount of 4 parts was 1, and the amount of vinyl toluene grafted was 12.
A diethyl itaconate/vinyltoluene grafted polyethylene wax (MW-4) containing 5i parts of O was obtained.

Next, instead of using MW-1 in Example 1, the MW-4
A toner was prepared in the same manner as in Example 1, except that a toner was used, and a copying test was conducted.

As a result, even after 5,000 copies, a copied image was obtained that was as clear as the initial image and free from any offset phenomenon or contamination, and no contamination of the heat roll or photosensitive drum was observed.

Example 5 In the same manner as in Example 1, 60 g of diethyl maleate was added to 500 g of [η) 0.22 g/a polypropylene wax (homopolymer) polymerized using a Ziegler type catalyst.
Added 65g of Sue F-Lev and 0.0g of DTBPOI,
A heating reaction was carried out at 170° C. for 3 hours to obtain a diethyl maleate/styrene grafted polypropylene wax (MW-5) containing 9.7 parts by weight of diethyl maleate graft and 111.2 parts by weight of styrene graft.

Next, instead of using MW-1 in Example 1, the MW-5
A toner was prepared in the same manner as in the example except that a copying test was conducted.

As a result, even after 3,000 copies, a copied image was obtained that was as clear as the initial image and free of offset phenomena, contamination, etc., and no contamination of the heat roll or photosensitive drum was observed.

Furthermore, in the same manner as in Example 3, the temperature change in fluidity of the toner was suppressed. As a result, when the toner was kept at 50° C. for 48 hours, the fluidity was slightly worse than when kept at room temperature, but no lumps were formed, suggesting that there was no problem in practical use.

Example 6 To 500 g of (η) 0.19 g/lU polybutene-1 wax (homopolymer) polymerized using a Ziegler type catalyst in the same manner as in Example 1, 65 g of n-butyl methacrylate, 23 g of styrene, and 3 g of DTBPOT were added. was added and reacted by heating at 160"C for 3 hours to obtain n-butyl methacrylate/styrene grafted polybutene-1 wax (MW- 6) was obtained.

Next, instead of using MW-2 in Example 2, the MW-6
A toner was prepared in the same manner as in Example 1, except that a toner was used, and a copying test was conducted.

As a result, even after 5000 copies, a copied image was obtained that was as clear as the initial image and free from offset development and staining, and no staining of the heat roll or photosensitive drum was observed.

Furthermore, a bending resistance test was conducted in the same manner as in Example 2. As a result, it was found that the fixation retention rate before and after the bending test was extremely high (and it was also excellent in the bending resistance test by 1).

Example 7 In the same manner as in Example 1, 40 g of 2-hydroxyethyl methacrylate and 3.3 g of DTBPO were added to 500 g of polyethylene wax of [η) 0.41 g/dl,
A heating reaction was carried out at 170°C for 4 hours to obtain 2-hydroxyethyl methacrylate grafted polyethylene wax (6.4 parts by weight of 2-hydroxyethyl methacrylate grafted amount).
MW-7) was obtained.

Next, 48 parts by weight of styrene n-butyl acrylate copolymer (Heimer S B M2O3, manufactured by Sanyo Chemical Industries, Ltd.), and carbon black (MA-100, manufactured by Mitsubishi Chemical Industries, Ltd.)
2 parts by weight, magnetic powder (Mabico Black Bt manufactured by Titanium Industries)
, -500) and the MW-82 weight part were mixed in a ball mill for 24 hours, kneaded with a heated roll for 1 hour, then finely pulverized with a jet mill, heat-treated with a spray dryer, and averaged with a zigzag classifier. A magnetic toner having a diameter of 15 μm was obtained. Using the magnetic toner, it was developed on a selenium photoreceptor by a conventionally known electrophotographic method, transferred onto transfer paper, and a durability test of 5,000 copies was conducted with the heating roll temperature set at 200°C. As a result, a good copy image was obtained without staining the heating roll.

Comparative Example 1 500 g of polypropylene wax (homopolymer) with [η) of 0.22 g/a polymerized using a Ziegler type catalyst in the same manner as in Example 1 and 5.0 g of diethyl male)
, and 0.5 g of DTBPO were added thereto and reacted by heating at 170° C. for 2 hours to obtain a diethyl maleate grafted polypropylene wax (MW-8) with a diethyl maleate graft amount of 0.9 parts by weight.

Next, a toner was prepared in the same manner as in Example 2 except that MW-8 was used instead of MW-2 in Example 2, and a copying test was conducted.

As a result, the sharpness of the image began to deteriorate around the 4000th copy. At the same time, a polypropylene wax film (filming phenomenon) was observed partially on the surface of the photoreceptor drum and iron powder carrier.

Furthermore, when a bending resistance test was carried out in the same manner as in Example 2, significant toner peeling was observed along the bending line, and the results were inferior to those in Example 2.

Comparative Example 2 In the same manner as in Example 1, 150 g of 2-ethylhexyl methacrylate and 8.5 g of DTBPO were added to 300 g of polyethylene wax of [η) 0.11 g/J,
Heat reaction at 160°C for 3 hours, graph) 1E3
2.8 parts by weight of 2-ethylhexyl methacrylate grafted polyethylene wax (MW-9) was obtained.

Then, instead of using MW-2 in Example 2, the MW-9
A toner was prepared in the same manner as in Example 2, except that a toner was used, and a copying test was conducted. As a result, the peelability from the hot roll was poor, and an offset phenomenon and staining of the copy paper were observed.

Furthermore, in the same manner as in Example 3, the temperature change in the fluidity of the toner was investigated.
The results showed that lumps of one corner or more were formed and the fluidity was poor, suggesting that there were problems in practical use.

Comparative Example 3 [η31.36/j/g, ethylene content 3.211I
Polypropylene containing 1% O was charged into an autoclave having an internal volume of 11, and thermally decomposed at 340° C. for 3.5 hours while passing a small amount of nitrogen.

Next, using the polypropylene wax, 1 part of 2-ethylhexyl methacrylate grafted polypropylene wax (MW-10) was prepared in the same manner as in Example 1.
I got it.

Next, in Example 1, instead of using MW-1, the M
The toner was prepared in the same manner as in Example 1 except that W-10 was used.
l! i1MI, conducted a copy test.

As a result, the peelability from the hot roll is significantly poor, and
A large amount of filming was observed on the photoreceptor drum and iron powder carrier.

Comparative Example 4 In the same manner as in Example 1, [η) 0.64 dl/H
70 g of 2-ethylhexyl acrylate and 5.8 g of DTBPO were added to 500 g of polyethylene wax.
A heating reaction was carried out at 180°C for 2 hours to obtain a 2-ethylexyl acrylate grafted polyethylene wax (MW-11) with a grafting amount of 11.8 parts by weight of 2-ethylhexyl acrylate.

Next, instead of using MW-1 in Example 1, the MW
A toner was prepared in the same manner as in Example 1, except that Toner-11 was used, and a 1000 copying test was conducted.

As a result, the peelability from the hot roll was poor, and an offset phenomenon and staining of the copy paper were observed.

Comparative Example 5 300 g of polypropylene used to prepare MW-10 of Comparative Example 3 was charged into an autoclave with an internal volume of 11.
Thermal decomposition was carried out at 340° C. for 2.2 hours while passing a small amount of nitrogen. [η
] is 0.10d! /g.

Next, in Example 2, a toner was prepared in the same manner as in Example 2 except that the above polypropylene wax was used instead of MW-2, and a copying test was conducted.

As a result, the sharpness of the image began to deteriorate around the 3500th copy. At the same time, a polypropylene wax film (filming development) was observed partially on the surface of the photoreceptor drum and iron powder carrier.

Furthermore, in the same manner as in Example 3, the temperature change in the fluidity of the toner was investigated.
In addition to producing lumps larger than m square, the fluidity was also extremely poor, suggesting a practical problem.

Applicant: Mitsui Petrochemical Industries, Ltd. Agent Kazu Yamaguchi Procedural amendment (voluntary) Showa ΔO February V day

Claims (1)

[Claims] (1) A modified polyolefin obtained by grafting 2 to 30 parts by weight of an unsaturated carboxylic acid ester to 98 to 70 parts by weight of polyolefin wax with an intrinsic viscosity of 0.07 to 0.6 dl/g (total of both is 100 parts by weight) A heat-fixable electrophotographic developer comprising a wax (A), a binder resin (B), and a colorant (C).