JPH0323906B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a toner for developing electrostatic images formed in electrophotography, electrostatic printing, electrostatic recording, etc., and a method for manufacturing the same. [Prior Art] An electrostatic image formed on an electrostatic image carrier such as a photoconductive photoreceptor is generally developed with a toner made of fine particles of binder resin containing a coloring agent, etc. . The obtained toner image is usually transferred onto an image support such as paper and fixed by a fixing process to obtain a desired recorded matter. Various methods are known for fixing toner images, but the contact heat fixing method represented by the heat roller fixer has higher thermal efficiency than the non-contact heating method such as the hot plate fixer. In particular, it has the advantage of being capable of high-speed fixing, and is widely used. However, in this method, the toner is brought into direct pressure contact with the high-temperature fixing roller surface and becomes thermally molten, so that the molten toner adheres to the fixing roller surface. The toner adhering to the fixing roller transfers onto the next image support and stains it, causing a so-called "offset" phenomenon.Furthermore, the image support is transferred to the fixing roller via the toner. It is necessary to prevent this phenomenon since it may cause the so-called "winding" phenomenon in which the film adheres and wraps around itself. In particular, it has been found that one of the causes of "wrapping" is that the temperature of the fixing roller decreases as a large number of copies are made. Various proposals have been made in the past to prevent these phenomena. For example, Japanese Patent Application Laid-Open Nos. 50-134652, 1982-144446, and 1984-3304 have methods for preventing the offset phenomenon. Although hard toner resins and toners have been disclosed, even these measures have not yet led to a satisfactory solution. Generally, vinyl resins are widely used as binders for toners, but one way to improve the offset resistance of toners using vinyl resins as binders is to use high molecular weight resins with high softening points. It is. However, when such a resin is used, the temperature required to fix the toner (hereinafter referred to as minimum fixing temperature) increases, and the advantages of the contact heat fixing method are lost. Naturally, it is desirable that the minimum fixing temperature be low, and the toner used in the recently developed method of forming toner images on both sides of a sheet of transfer paper is required to be able to be fixed at a low temperature. Improvements are desired. In addition, in order to reduce the adhesion force between the fixing roller surface and toner, the fixing roller is coated with a fluororesin or the like, and a lubricating liquid such as silicone oil is supplied to the surface to form a liquid layer on the fixing roller surface. A method is used in which a mold release effect is provided by using a mold release method. However, this method requires a high-precision device to stably supply the liquid, or the lubricating liquid may be heated and emit an odor, and the image recording device as a whole becomes complicated and expensive, resulting in environmental disadvantages. It was hot. Furthermore, as a method for preventing "offset" and "wrapping" without supplying a lubricating liquid to the surface of the fixing roller, Japanese Patent Application Laid-Open No. 153944/1983 discloses a method of containing polyolefin wax as a release agent in the toner. is disclosed. On the other hand, various methods are used to manufacture toner, such as kneading molten resin and colorant, cooling and solidifying it, and finely pulverizing it to form toner, and further spraying and heating to form spherical shapes. A method of obtaining a toner by polymerizing a mixture of a coloring agent and a polymerizable monomer and then finely pulverizing it to obtain a toner, or a method of obtaining a toner by polymerizing a mixture of a colorant and a polymerizable monomer, or adding a mixture of a colorant and a polymerizable monomer to a medium such as water in the form of fine particles. There are methods of producing toner particles by dispersing the toner particles in a liquid and polymerizing them in a suspended state. Particularly, a method using suspension polymerization has the advantage that the process is relatively short and that spherical particles can be obtained. It has been found that the effect of the release agent added to the toner differs depending on the method of manufacturing the toner as described above. For example, it has been found that when a toner is manufactured by a suspension polymerization method, even if a release agent is added to the polymerizable monomer, the effect of preventing "offset" and "wrapping" is reduced. To produce toner containing a release agent using the suspension polymerization method, a colorant and a release agent such as wax are usually added to liquid polymerizable monomers, and the mixture is subjected to strong shearing using a sand stirrer or other device. The colorant is uniformly dispersed by applying force to form a polymerizable composition, and at this time the release agent is also dispersed in the form of extremely fine particles. The polymerizable composition can be suspended in an aqueous medium to proceed with the polymerization reaction, but since the mold release agent is generally lipophilic and strongly hydrophobic, it gets buried inside the oil droplets of the polymerizable composition when suspended. When it becomes toner particles, it does not appear on the surface of the toner particles, so it is no longer effective as a release agent. As can be inferred from this example, the effect of the release agent added to the toner depends on the state of the release agent in the toner. As mentioned above, it is difficult to obtain a toner with a low minimum fixing temperature while achieving sufficient offset resistance, and it is extremely difficult to solve this problem, especially when vinyl monomers are used. It happened. [Object of the Invention] The object of the present invention is to provide a toner for developing electrostatic images that has excellent releasability from the surface of a fixing roller, does not cause "offset" or "wrapping", and can be fixed at a low fixing temperature, and the same. The purpose is to provide a manufacturing method. Another object of the present invention is to provide a toner for developing electrostatic images that can be fixed at low temperatures and has excellent blocking resistance, and a method thereof. Another object of the present invention is to provide a toner for developing electrostatic images that has excellent fluidity, cohesiveness, and powder properties, and has good replenishment and storage stability, and a method for producing the same. Another object of the present invention is to provide a two-component toner for developing electrostatic images that is free from carrier contamination caused by carrier adhesion and fusing, and a method for producing the same. Another object of the present invention is to provide a method for producing a toner for developing electrostatic images that is easy to produce, allows stable production, and is inexpensive. [Structure of the Invention] The above object is to disperse a polymerizable composition formed by dispersing a colorant, a polyolefin wax, and a non-polyolefin wax other than polyolefin in a polymerizable monomer in an aqueous solvent, and to carry out suspension polymerization. In a method for producing a toner for electrostatic image development (hereinafter sometimes simply referred to as toner), the ratio of the average particle size D ₁ of the polyolefin wax to the average particle size D ₂ of the toner
This was achieved by a method for producing a toner for electrostatic image development, characterized in that D ₁ /D ₂ is 0.4 to 2, and the polyolefin wax is pulverized in advance to have D ₁ of 2 to 60 μm. The "offset" and "wrapping" prevention effects of polyolefin waxes in toners produced by polymerization methods are synergistically enhanced when used in combination with non-polyolefin waxes.
In this case, the present inventors made the particle size D ₁ of the polyolefin wax in the toner relatively larger than the toner particle size D ₂ and set D ₁ /D ₂ to 0.4 to 2 to further significantly strengthen the wax. This discovery led to the present invention. The effect of making the particle size of the polyolefin wax a certain ratio with the particle size of the toner is that the polymerizable composition consisting of the colorant, polyolefin wax, non-polyolefin wax, polymerizable monomer, etc. This is particularly effective when producing a toner by a suspension polymerization method in which the toner is dispersed and suspended in an aqueous medium and then polymerized. If the ratio D ₁ /D ₂ of the average particle diameter of polyolefin particles and toner particles is less than 0.4, there will be no releasing effect or strengthening effect, and if it is more than 2, it will be difficult to contain polyolefin particles in the toner particles, so this is a preferred toner. is not obtained. The polyolefin wax preferably used in the present invention may be either a homopolymer obtained from a single olefin monomer or a copolymer obtained by copolymerizing the olefin monomer with another monomer copolymerizable therewith. Examples of the olefin monomer include ethylene, proprene, butene-1, pentene-1,
Hexene-1, heptene-1, octene-1, nonene-1, decene-1, and their isomers with different positions of the unsaturated bond, as well as e.g. 3-methyl-1-butene, 3-methyl-2 -Pentene, 3
- Acrylic acid derivatives such as proacrylonitrile, N,N-dimethylacrylamide, organic acids such as acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, diethyl fumarate, β-pinene, etc. can be mentioned. Further, as a useful wax, a modified polyolefin obtained by blocking or grafting the above-mentioned polyolefin with other components can also be used. Examples of modification components in this case include styrene, p-methylstyrene, α-methylstyrene,
Aromatic vinyl monomers such as 3,4-dichloro-styrene, unsaturated fatty acid monomers such as acrylic acid, methacrylic acid, ethyl acrylate, methyl methacrylate, and their esters are useful. The monomers include those having a branched alkyl group such as pyru-5-methyl-2-hexene, and all other olefin monomers, but ethylene and propylene are particularly preferred. Other monomers copolymerizable with the olefin monomer include other olefin monomers, such as vinyl methyl ether, vinyl-n-
Vinyl ethers such as butyl ether and vinyl phenyl ether; vinyl esters such as vinyl acetate and vinyl butyrate; haloolefins such as vinyl fluoride, vinylidene fluoride, tetrafluoroethylene, vinyl chloride, vinylidene chloride, and tetrachloroethylene; For example, methyl acrylate, ethyl acrylate, n-butyl acrylate, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate,
Acrylic acid esters or methacrylic acid esters such as stearyl methacrylate, N,N-dimethylaminoethyl methacrylate, t-butylaminoethyl methacrylate, acrylic acid derivatives such as acrylonitrile, N,N-dimethylacrylamide, etc. acrylic acid,
Organic acids such as methacrylic acid, maleic acid, fumaric acid, itaconic acid, diethyl fumarate, β-
Various examples can be mentioned, such as vinylene. Further, as a useful wax, a modified polyolefin obtained by blocking or grafting the above-mentioned polyolefin with other components can also be used. Examples of modification components in this case include styrene, p-methylstyrene, α-methylstyrene,
Aromatic vinyl monomers such as 3,4-dichloro-styrene, unsaturated fatty acid monomers such as acrylic acid, methacrylic acid, ethyl acrylate, methyl methacrylate, and their esters are useful. These polyolefin waxes can be used alone or in combination of two or more. The preferred amount of polyolefin wax used is the polymerizable monomer
Preferably 3 to 40 parts by weight per 100 parts by weight, and 5 parts by weight.
It is particularly preferred that the amount is from 35 parts by weight. Specific examples of polyolefin waxes useful in the present invention are listed below, but it goes without saying that the polyolefin waxes used in the present invention are not limited to these. Polyoleviscol 330-P,
Viscole 550-P, Viscole 660-P (and above,
Manufactured by Sanyo Chemical Co., Ltd., polypropylene), Hiwax
320P, Hiwatux 310P, Hiwatux 410P,
Hiwax 405P, Hiwax 400P, Hiwax 200P (manufactured by Mitsui Petrochemical Co., Ltd., polyethylene), Sanwax 131-P, Sanwax 151
-P, Sunwax 161-P, Sunwax 165-
P, Sanwax 171-P (manufactured by Sanyo Chemical Co., Ltd., polyethylene), Polywax 400, Polywax
500, Polywax 465, Polywax 1040 (polyethylene manufactured by Toyo Petrolite Co., Ltd.). Any method can be used to adjust the D ₁ /D ₂ ratio in the toner to the value of the present invention, but the most preferred method is to crush the polyolefin wax in advance with a jet mill, sand mill, etc. Alternatively, it is made into a fine powder with the required particle size by methods such as spray drying, recrystallization, reprecipitation, etc., and this is added to a polymerizable composition consisting of a colorant, etc. in a polymerizable monomer, and dispersed to cause polymerization. Alternatively, the mold release agent may be added to the polymerizable composition as it is, and the polymerization may be carried out by submergedly crushing the mold release agent to a predetermined particle size using a shearing force dispersion device such as a sand mill. The average particle size _D2 of commonly used toners is in the range of 5 to 30 μm,
The average part D ₁ of the part of the mold release agent is 2 to 60 μm accordingly.
However, the average diameter of the toner is not limited to this range and may be set as necessary, and the average diameter of the release agent part is also adjusted to D ₁ /D ₂ = 0.2 to 2.0 accordingly. Just adjust it accordingly. The average diameter referred to herein is the weight average particle diameter measured with a Coulter Counter (manufactured by Coulter Inc.). Particularly preferred non-polyolefin waxes to be used in combination with the polyolefin wax are:
For example, Ceresin, paraffin wax 150, paraffin wax 155, paraffin wax-140, paraffin wax-135, paraffin wax 130,
Parafine wax-125, parfine wax-120, parfine wax-115, parfine wax-SP-0145, parfine wax-SP-
1035, paraffin wax-SP-1030, paraffin wax-SP-3040, paraffin wax-SP-3035, paraffin wax-SP-3050
(The above are manufactured by Nippon Seisaku Co., Ltd.) Nisseki No. 1 Candle Wax, Nisseki No. 2 Candle Wax, 140° Paraffin, 135° Paraffin, 125° Paraffin, Paraffin Wax M, 125° Special Paraffin (made by Nippon Oil Co., Ltd.) and other paraffin waxes,
Petrolite WB-5, Petrolite WB-16,
Petrite WB-17 (manufactured by Bareyu), NPS-
Oxidized paraffin waxes such as 6115, NPS-9210 (manufactured by Nippon Seiwa Co., Ltd.), tristearin, Hoechstwax F, Hoechstwax E, Hoechstwax KFO, Hoechstwax KP, Hoechstwax KSS ( (Manufactured by Hoechst AG) etc. Partially saponified fatty acid ester waxes, Hoechstwax- such as fatty acid ester waxes, Hoechstwax OP, Hoechstwax C (Hoechst AG)
Fatty acid amide S, fatty acid amide T, fatty acid amide P, fatty acid amide C, fatty acid amide O, fatty acid amide O-3, Kaoh wax EB
(manufactured by Kao Soap Co., Ltd.), fatty acid amide waxes such as Aramide C, Aramide O, Aramide HT, Aramide 18, Armowax, Armowax EBS (manufactured by Lion Akzo Co., Ltd.), Nisseki Micro Wax 155, Nisseki Micro Watkus 180 (manufactured by Nippon Oil Co., Ltd.), Hi-Mic-2095, Hi-Mic-
1080, Hi-Mic-1070, Hi-Mic-2065, Hi-
Mic-1045, Hi-Mic-2045 (Nippon Seiro Co., Ltd.)
microcrystalline waxes such as (precious), other polyamides, and rice waxes No. 1 as a mixed product.
1. Rice wax L-301-J, rice wax F-1, rice wax M-200, Naba wax, beeswax, K-1, popko-201,
popko-202, popko-203 (Noda Wax Co., Ltd.)
(manufactured by), etc., but is not limited to these. The polyolefin waxes and non-polyolefin waxes may be used alone or in combination of two or more. The preferred amount of the polyolefin wax and non-polyolefin wax added is in the range of 7 to 50 parts by weight based on 100 parts by weight of the polymerizable monomer used in the toner. If the amount of wax is 7 parts by weight, the release effect of the wax will be insufficient, and if it is more than 50 parts by weight, the viscosity of the polymerizable composition will become extremely high, making production difficult. The ratio of polyolefin wax to non-polyolefin wax used is preferably 90:10 to 10:90. Even if the ratio of non-polyolefin wax is below or above the above range, the releasability of the resulting toner will be reduced and "offset" and "wrapping" may occur.
is more likely to occur. Examples of the polymerizable monomer that can be used in the present invention include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene,
α-methylstyrene, p-ethylstyrene, 2,
4-dimethylstyrene, p-n-butylstyrene, p-tert-butylstyrene, p-n-hexylstyrene, p-n-octylstyrene, p-n
-nonylstyrene, p-n-decylstyrene, p
Preferred examples include styrene monomers such as -n-dodecylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, and 3,4-dichlorostyrene. In addition, for example, ethylenically unsaturated monoolefins such as ethylene, propylene, butylene, and isobutylene; vinyl halides such as vinyl chloride, vinylidene chloride, vinyl bromide, and vinyl fluoride; vinyl acetate, vinyl propionate, and vinyl benzoate. ,
Vinyl esters such as vinyl butyrate; methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, propyl acrylate, n-octyl acrylate, dodecyl acrylate, lauryl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, acrylic acid 2
-Chlorethyl, phenyl acrylate, methyl α-chloroacrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate,
n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethyl methacrylate α-methylene aliphatic monocarboxylic acid esters such as aminoethyl and diethylaminoethyl methacrylate; Acrylic acid or methacrylic acid derivatives such as acrylonitrile, methacrylonitrile, and acrylamide; Vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, etc. Vinyl ethers; vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, and methyl isopropenyl ketone; N-vinyl compounds such as N-vinylpyrrole, N-vinylcarbazole, N-vinylindole, and N-vinylpyrrolidone; vinylnaphthalenes, Others can be mentioned. These monomers can be used alone or in combination, or can be polymerized to form a co-assembly. Although the molecular weight of the polymer according to the present invention is arbitrary,
Preferably, the weight average molecular weight is 50,000 to 1,000,000, and the number average molecular weight is 1,000 to 1,000,000. The polymer according to the present invention may be polymerized in the presence of a crosslinking agent to form a crosslinked polymer. Preferably used crosslinking agents are mainly compounds having two or more polymerizable double bonds, such as aromatic divinyl compounds such as divinylbenzene, divinylnaphthalene, and derivatives thereof, such as ethylene glycol dimethacrylate, diethylene glycol methacrylate. , diethylene glycol methacrylate, trimethylolpropane triacrylate, allyl methacrylate, t-butylaminoethyl methacrylate, tetraethylene glycol dimethacrylate, 1,3-butanediol dimethacrylate, etc., N,N divinylaniline , divinyl ether, divinyl sulfide, divinyl sulfone, and compounds having three or more vinyl groups are selected singly or as a mixture. For the polymerization of vinyl monomers as described above, a polymerization initiator is usually used in an amount of 0.1 to 10% by weight based on the polymerizable monomer. Specific examples of typical polymerization initiators include acetylcyclohexylsulfonyl peroxide, isodibutyl peroxide, diisopropyl peroxydicarbonate, di-2-ethylhexyl peroxydicarbonate, 2,4-dichlorobenzoyl peroxide, t -butyl peroxypivalate, 3,
5,5-trimethylhexanoyl peroxide, octanoyl peroxide, decanoyl peroxide, lauroyl peroxide, stearoyl peroxide, propionyl peroxide, succinic acid peroxide,
Acetyl peroxide, t-butylperoxy-2-ethylhexanoate, benzoyl peroxide, parachlorobenzoyl peroxide, t-butylperoxyisobutyrate, t-
Butyl peroxymale acid, t-butyl peroxylaurate, cyclohexanone peroxide, t-butyl peroxyisopropyl carbonate, 2,5-dimethyl-2,5-dibenzoyl peroxyhexane, t-butyl peroxy Acetate, t-butyl peroxybenzoate, diisobutyl diperoxy phthalate, methyl ethyl ketone peroxide, dicumyl peroxide, 2,5-dimethyl-2,5-di t-
Butyl peroxyhexane, t-butylcumyl peroxide, t-butyl hydroperoxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-di-t-butyl peroxyhexane, diisopropylenenzene hydroperoxide , peroxide initiators such as paramethane hydroperoxide, pinane hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, cumene hydroperoxide,
2,2'-azobisisobutyronitrile, 1,1'-
Azobis(cyclohexane-1-carbonitrile), 2,2'-azobis4-methoxy-2,4-
Dimethylvaleronitrile, 2,2'-azobis-
Examples include azo initiators such as 2,4-dimethylvaleronitrile. In carrying out the method of the present invention, a plurality of polymerization initiators having different radical half-lives can be used. In this case, at a certain polymerization temperature, a polymerization initiator with a short half-life forms a so-called rapid initiation system, and a polymerization initiator with a long half-life forms a so-called slow initiation system, and a rapid initiation system is formed with a polymerization initiator with a long half-life. In the initiation system, a polymer with a low degree of polymerization and a low molecular weight is formed, and at the same time, in the slow initiation system, a polymer with a high degree of polymerization and a high molecular weight is formed. According to a toner made of a polymer consisting of a low molecular weight polymer portion and a high molecular weight polymer portion, the minimum fixing temperature is low due to the low molecular weight polymer portion, and offset occurs due to the high molecular weight polymer portion. The temperature becomes high. A preferred example of a polymerization initiator with a short half-life is 2,2'-azobis-4-methoxy-2,4-
Dimethylvaleronitrile, 2,2'-azobis-
Examples include 2,4-dimethylvaleronitrile, and preferred examples of polymerization initiators with a long half-life include 1,1'-azobis(cyclohexane-1-carbonitrile). Coloring agents include carbon black, nigrosine dye (CI No. 50415B), and aniline blue (CI No.
50405), Calco Oil Blue (CINo.azoic
Blue8), Chrome Yellow (CINo.14090), Ultramarine Blue (CINo.77103), Dupont Oil Red (CINo.26105), Quinoline Yellow (CI
No.47005), methylene blue chloride (CINo.
52015), Phthalocyanine Blue (CINo.74160),
Malachite Green Oxalate (CINo.
42000), lampblack (CI No. 77266), rose bengal (CI No. 45435), mixtures thereof, and others. These colorants need to be contained in a sufficient proportion to form a visible image of sufficient concentration, and are usually used in binder resins.
The proportion is about 1 to 20 parts by weight per 100 parts by weight. When polymerization is carried out by the suspension polymerization method, the polymer composition is dispersed and suspended in a dispersion medium such as water as fractional particles of the desired particle size by mechanical stirring, and the polymerization is carried out. It is necessary to prevent the dispersed particles from coalescing into large particles due to their increasing stickiness as the process progresses, and a suspension stabilizer is used for this purpose. The suspension stabilizers used as such suspension stabilizers are generally divided into water-soluble polymeric substances and fine powders of poorly soluble inorganic compounds.The former includes gelatin, starch, polyvinyl alcohol, and others, and the latter includes Barium sulfate, calcium sulfate, barium carbonate, calcium carbonate, calcium phosphate, and other sparingly soluble salts, and combinations of sparingly soluble salts and surfactants such as sodium dodecylbenzenesulfonate and sodium dodecyl sulfate, talc, viscosity, silicic acid,
Includes inorganic polymer substances such as diatomaceous earth, metal oxides, and other powders. In addition, the polymer composition is an ionic substance,
For example, by containing a cationic substance or anionic substance such as a nitrogen-containing polymerizable monomer or poorly water-soluble amines, the dispersed particles become positively or negatively charged when dispersed in water. In such cases, ionic dispersants that are charged to the other polarity when dispersed in water, such as negatively charged colloidal silica or positively charged aluminum oxide, can be effectively used as suspension stabilizers. . In addition to these, the toner of the present invention may contain a magnetic substance, a charge control agent, a dispersant, etc., as necessary. Magnetic materials include ferrite, magnetite, iron, cobalt, nickel, and other ferromagnetic metals or alloys, or compounds containing these elements, or materials that do not contain ferromagnetic elements but can be made by applying appropriate heat treatment. Mention may be made of alloys which become ferromagnetic over time, such as alloys of the type called Heusler alloys containing manganese and copper, such as manganese-copper-aluminum, manganese-copper-tin, or chromium dioxide, among others. To produce the toner of the present invention by suspension polymerization, first add the required amount of colorant, polyolefin wax, non-polyolefin wax, other additives, etc. to the polymerizable monomer, and then sand the toner. Stir and disperse well using a stirrer etc. to obtain a polymerizable composition. After adding a polymerization initiator, add it to an aqueous suspension medium containing a suspension stabilizer and disperse using a high speed stirrer etc. The suspension is maintained under appropriate temperature conditions to allow the polymerization reaction to proceed. The polymerizable composition suspended as fine oil droplets in the medium is directly polymerized and solidified to obtain spherical resin particles containing colorant, wax, etc. The size of the resulting resin particles is determined by the dispersion state of the suspended polymerizable composition, so if you adjust the dispersion conditions and suspend the toner to the desired particle size, the resin particles obtained will remain as they are. Can be used as a toner. The toner of the present invention is mixed with a carrier made of iron powder, glass beads, etc. to form a two-component developer, but when it contains a magnetic material, it can be directly subjected to the electrostatic image phenomenon as a one-component developer. Ru. [Example] The present invention will be specifically explained below with reference to Examples, but the embodiments of the present invention are not limited thereto. Note that the numbers in this example represent parts by weight unless otherwise specified. Example 1 Polypropylene “Viscol 660P” (Sanyo Chemical Co., Ltd.)
Co., Ltd.) was ground in methanol with a sand stirrer to obtain a fine powder, which was measured using a Coulter Counter (Coulter Co., Ltd.), and the weight average particle size was 10.4 μm. Styrene 90 parts (n)butyl acrylate 10 parts Carbon Black #30 (manufactured by Mitsubishi Kasei Corporation) 10 parts POPKO-201 (manufactured by Noda Wax Co., Ltd.) 8 parts 2,2'-azobis(2,4-methyl After mixing and dispersing 3 parts of (valeronitrile) with a sand stirrer, the previously obtained "Viscol 660P" 8 with a weight average particle size of 10.4 μm
A polymerizable composition was obtained.
Add this to an aqueous solution containing 3.0% by weight of calcium phosphate (based on the polymerization composition) and 0.04% by weight of sodium dodecylbenzenesulfonate (based on the polymerization composition) in an amount to give 20% by weight (solid content concentration). A suspension was obtained by dispersing the particles to a particle size of 7 to 15 μm using a TK homogenizer (manufactured by Tokushu Kika Kogyo Co., Ltd.).Then, this suspension was heated at 50°C for 20 hours and then heated to 85°C.
The mixture was polymerized by heating at ℃ for 3 hours, treated with hydrochloric acid, filtered, washed, and dried to obtain the toner of the present invention. This toner has a weight average particle size of 11.3 μm as measured by Coulter Counter, and the weight average particle size ratio of polypropylene and toner is
It was 10.4/11.3=0.92. 2 parts of this toner and hydrophobic silica (manufactured by Degussa)
A developer consisting of 0.016 parts was prepared and evaluated as follows. [1] Measuring the temperature at which "winding" occurs. For testing, we used an electronic copying machine U-Bix1600 (manufactured by Konishiroku Photo Industry Co., Ltd.) that had been modified so that the temperature of the fixing heat roller could be variably set. A transfer paper with a solid black toner image formed on the leading edge is fixed while gradually lowering the temperature from 230°C in 5°C increments, and the temperature at which the transfer paper starts to wrap around the heated roller (wrapping temperature) is determined. The surfaces of the fixing roller and pressure roller were made of Teflon and silicone rubber "KE-1300R-TV", respectively, and the transfer material passing speed was 120 mm/sec. Silicone oil is not supplied to the fixing section. [2] Measurement of minimum fixing temperature and offset occurrence temperature Using the same test electronic copying machine as in the previous section, the transfer paper on which the toner image was formed was heated at 146 mm/sec while increasing the set temperature of the fixing heat roller in steps of 5°C. The surface of the resulting image was rubbed with paper to check its abrasion resistance, and the temperature at which the image had sufficient abrasion resistance was determined as the lowest fixing temperature. Further, following the transfer paper with an image, a transfer paper without an image was passed through the fixing section and observed whether or not toner staining occurred due to the offset phenomenon, and the temperature at which the staining occurred was taken as the offset occurrence temperature. In addition, the "winding" occurrence temperature, minimum fixing temperature, and offset occurrence temperature measured using this method were each 200%.
℃ or lower, 170℃ or lower, and 230℃ or higher are practically preferable. The measurement results for the sample toner showed that the curling temperature was 175°C and the minimum fixing temperature was 180°C, and no offset occurred in the entire range of measured temperatures, indicating excellent characteristics. Examples 2 to 8 Polyolefin wax “Viscol 660P” of Example 1 and non-polyolefin wax “POPKO・
Samples 2 to 8 were prepared in the same manner as in Example 1 except that "201" was replaced with a polyolefin wax or a non-polyolefin wax shown in Table 1, respectively.

[Table] Using these toner samples, developers were prepared in the same manner as in Example 1, and the "wrapping" occurrence temperature, minimum fixing temperature, and offset occurrence temperature were measured. Furthermore, D ₁ /D ₂ was determined for each toner. The measurement results are shown in Table 2. Example 9 Low molecular weight polypropylene “Viscol 550P”
(manufactured by Sanyo Chemical Co., Ltd.) was ground in advance in methanol with a sand stirrer and measured with a Coulter counter (manufactured by Coulter Co., Ltd.) to obtain particles with a weight average particle diameter of 10.0 μm. On the other hand, styrene 85 parts (n)butyl methacrylate 15 parts ethylene glycol dimethacrylate 0.4 parts Carbon black "MONARCH880" (manufactured by Cabot) 10 parts Ceresin 8 parts 2,2'-azobis(2,4-dimethylvaleronitrile) ) 3 parts were mixed and dispersed using a sand stirrer, and then the previously obtained polypropylene 8 having a weight average particle size of 10.0 μm was mixed and dispersed.
of the mixture was added and uniformly dispersed to obtain a polymerizable composition. Thereafter, suspension polymerization was carried out in the same manner as in Example 1 to obtain a toner sample, and the same evaluation as in Example 1 was performed using this sample. The evaluation results are shown in Table 2. Example 10 Using polyethylene wax "Polywax 500" (manufactured by Toyo Petrolite Co., Ltd.), a polyethylene wax having a weight average particle size of 9.5 μm was obtained in the same manner as in Example 1. Styrene 82 parts 2-methylhexyl acrylate 18 parts popko-201 8 parts Carbon black "Elftex 8" (manufactured by Cabot) 15 parts Polyester resin 3 parts 2,2'-azobis(2,4-dimethylvaleronitrile) 5 After mixing and dispersing 1 part with a sand stirrer, 8 parts of the previously obtained finely powdered polyethylene wax were added and uniformly dispersed to obtain a polymerizable composition. The polyester resin in the above formulation is an unsaturated polyester with a softening point of 110°C obtained by condensing bisphenol A, polyethylene glycol (average molecular weight 1000), terephthalic acid, and fumaric acid (weight ratio 200:20:100:70). . The obtained polymerizable composition was added to water containing 3% by weight of calcium phosphate (based on the polymerizable composition) and 0.04% by weight of sodium dodecylbenzenesulfonate (based on the polymerizable composition) to give a concentration of 30% by weight (solid content). A certain amount was added and dispersed using a TK homogiator. The suspension thus obtained was heated at 60°C for 20 hours to polymerize, then treated with hydrochloric acid, filtered, washed, and then
The toner of the present invention was obtained by drying. The weight average particle size of the toner thus obtained was 10.0 μm, and the polyethylone/toner particle size ratio was 0.95. This toner was evaluated in the same manner as in Example 1. In this case, the offset phenomenon did not occur over the entire range of measured temperatures. Also, recently the fixing temperature was 180°C. Comparative Example 1 Example 1, which is a non-polyolefin wax
The same operation as in Example 1 was performed except that POPKO-201 was not used, and the coiling temperature was 230°C.
Minimum fixing temperature 230℃ or higher, offset occurrence temperature 220℃
℃ occurred. That is, unless a wax other than polyolefin is used, the wrapping is insufficient, the offset property is poor, and the minimum fixing temperature is too high. Comparative Example 2 Polypropylene "Viscoll 660P" having a weight average particle diameter of 4.0 μm was obtained by reprecipitating polypropylene from a toluene solution into methanol. In place of the 12.6 μm polypropylene in Example 1, this
A comparative toner having a weight average particle size of 11.8 μm was obtained in the same manner as in Example 1 except that 8 parts of 4.0 μm polypropylene was used. In this case, the ratio of the weight average particle diameters of polypropylene and toner was 0.34. This sample was tested in the same manner as in Example 1.
Obtained the results in the table. Due to the small particle size ratio, sufficient effects could not be obtained even when a polyolefin wax and a non-polyolefin wax were used together. Comparative Example 3 Polyethylene "Hiwax 320P" (manufactured by Mitsui Petrochemicals) was reprecipitated from a toluene solution into methanol to obtain a polyethylene having a weight average of 3.8 μm. Meanwhile, styrene 85 parts n-butyl acrylate 15 parts ethylene glycol dimethacrylate 0.4 parts Carbon Black #30 (manufactured by Mitsubishi Chemical Corporation) 10 parts Ceresin 8 parts 2,2'-azobis(2,4-dimethylvaleronitrile) 3 parts After mixing and dispersing with a sand grinder, 8 parts of the previously obtained polyethylene having a weight average particle size of 3.8 μm was added and uniformly dispersed to obtain a polymerizable composition. The subsequent operations were performed in the same manner as in Example 1. The particle size of the comparative sample toner obtained was 12.0 μm, and the particle size ratio to that of the polyolefin wax was 0.32. This toner was evaluated in the same manner as in Example 1, and the results shown in Table 2 were obtained. As in Comparative Example 2, good results could not be obtained because the particle size ratio was inappropriate. Table 2 summarizes the experimental results for each toner obtained in Examples 1 to 10 and Comparative Examples 1 to 3 above.

〔Effect of the invention〕

As is clear from the above examples, the present invention makes it possible to obtain an excellent toner that has high releasability from the fixing roller surface, high offset resistance and wrapping resistance, and can be fixed at low temperatures. . By using the toner of the present invention, there is no need to supply lubricating liquid to the surface of the fixing roller.
It has become possible to perform good hot roller fixing without occurrence of "winding".

Claims (1)

[Claims] 1. Production of toner for electrostatic image development by dispersing a polymerizable composition comprising a colorant, a polyolefin wax, and a non-polyolefin wax other than polyolefin dispersed in a polymerizable monomer in an aqueous solvent and polymerizing the suspension. In the method, the ratio D ₁ /of the average particle diameter D ₁ of the polyolefin wax to the average particle diameter D ₂ of the toner is
A method for producing a toner for electrostatic image development, characterized in that D ₂ is from 0.4 to 2, and the polyolefin wax is pulverized in advance to have D ₁ from 2 to 60 μm.