JPH0675421A - Electrophotographic toner composition - Google Patents

Abstract

PURPOSE:To obtain an electrophotographic toner compsn. adaptable to a high- speed copying machine and a copying machine adopting fixation with a small quantity of heat, fixable with a small quantity of heat and excellent in anti- offsetting property by using a specified ABA type block copolymer. CONSTITUTION:This electrophotographic toner compsn. contains an ABA type block copolymer consisting of blocks A of a polymer having <=50 deg.C glass transition temp. and blocks B of a polymer having >=10 deg.C glass transition temp. in (1 :0.05)-(1:2,000) weight ratio. In the blocks A, a polymer of a vinyl monomer represented by the formula and/or a vinyl monomer represented by a formula CH2=CH-QR<2> is contained by 0.3-10wt.%. In the formulae, R<1> is H or methyl and R<2> is 1-13C straight chain or branched alkyl, 1-10C cycloalkyl, alkenyl, alkynyl, aralkyl, (substd.) phenyl, haloalkyl, oxyalkyl, aminoalkyl or thioalkyl.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an electrophotographic toner composition for developing an electrostatic image in electrophotography, electrostatic recording, electrostatic printing and the like.

[0002]

2. Description of the Related Art In recent electrophotographic copying systems, a thermal roll fixing system is generally used because of its high thermal efficiency, excellent fixing property, good image quality, and compact size of the apparatus. . In particular, the heat roll fixing method is suitable for high-speed fixing. However, the fixing method is not preferable because a so-called offset phenomenon occurs in which the toner is softened by heating and becomes sticky, and a part of the toner adheres to the surface of the heat roll. Conventionally, various proposals have been made to prevent this offset phenomenon. For example,
A method is used in which the surface of a heat roll is coated with a fluorine-based resin or the like to impart releasability, and a liquid for offset prevention such as silicone oil is applied to the surface.
This method is extremely effective in preventing the offset phenomenon, but the offset prevention liquid is heated and deteriorates,
There is a drawback that it requires an apparatus for generating an offensive odor and replenishing the offset prevention liquid, the copying machine becomes large in size, its structure becomes complicated, and high accuracy is required for stability, so that it becomes expensive. . Therefore, an offset prevention method that does not require an offset prevention liquid has been studied. For example, JP-A-49-65231 discloses a technique for preventing the offset phenomenon by blending a small amount of low molecular weight polypropylene in a toner composition.

With respect to the binder resin of toner, various studies have been conducted to prevent offset, for example, Japanese Patent Publication Sho.
Japanese Patent Publication No. 51-23354 discloses a technique of using a crosslinkable polymer as a binder resin. Furthermore, JP-A-50-13
Japanese Patent No. 4652 discloses that a resin having a large molecular weight distribution is used as a binder resin. In addition, JP-A-58-68752
In the publication, a polymer obtained by graft-copolymerizing a modified epoxy resin having a vinyl group and a polyester resin having a vinyl group is used as a binder resin. However,
When low molecular weight polypropylene is used as an offset preventive agent, the toner tends to become non-uniform, causing fog and scattering. Therefore, it is preferable that the amount used is as small as possible. Further, when a crosslinkable polymer or a polymer obtained by graft-copolymerization is used, the fixing property generally decreases, and the tendency becomes more remarkable as the fixing speed increases. Further, when a resin having a large molecular weight distribution is used, it is possible to achieve offset prevention without impairing the fixability, but it is generally not easy to produce such a resin, and it is also economically disadvantageous. There is. On the other hand, copiers are oriented toward higher speeds, and the contact time with the fixing roll is inevitably shortened, and there is a demand for toner that melts by heating for a short time.
Further, from the viewpoint of energy saving or safety, there is a need for a toner that melts at a temperature as low as possible and has good fluidity when melted. In order to meet these requirements, it has been attempted to reduce the molecular weight of the resin used, but the decrease in the molecular weight causes an insufficient cohesive force of the resin and an offset phenomenon is likely to occur, which is not preferable.

It is known that a block copolymer has a so-called sea / island structure, and a technique of using this block copolymer as a binder resin for toner has also been disclosed. For example, in Japanese Examined Patent Publication (Kokoku) No. 57-6585, ABA type, which is a soft polymer having a glass transition temperature of A block of less than 20 ° C. and a glass transition temperature of B block of more than 50 ° C. as a resin for pressure fixing toner, is ABA type. A method using a block copolymer is disclosed. Currently, the most common fixing method is a heating method. In particular, the pressure heating method using a heat roller performs fixing by allowing the toner image surface of the sheet to be fixed to pass under pressure while contacting the surface of the heat roller whose surface is formed of a material having releasability for toner. Is. In this method, the surface of the heat roller and the toner image on the sheet to be fixed come into contact with each other under pressure, so the thermal efficiency at the time of fusing the toner image to the sheet to be fixed is extremely good, and quick fixing can be performed. It is very effective in electrophotographic copying machines. However, the temperature inside the machine may rise due to the heat during fixing. For this reason, an undesired phenomenon that the toner blocks may occur in the state where the toner cartridge is set in the machine, and recently, the demand for blocking has also become strict. In such heat fixing, the toner obtained by using a resin having a soft polymer having a glass transition temperature lower than 20 ° C. in the A block is likely to be blocked in the apparatus, and as a result, the fluidity of the powder is poor and a good image is obtained. Hard to get. Further, fixing is possible as described in the heat fixing, but since the soft polymer having a glass transition temperature of lower than 20 ° C. occludes the sea part of the sea / island structure,
There is a problem that high-temperature offset is likely to occur and therefore the fixing temperature range is narrowed for heat fixing.

[0005]

The present invention is applicable to recent high-speed copying machines and low-calorific fixing copiers, is capable of fixing with a low calorific value, and has excellent offset resistance. Is for giving.

[0006]

The present inventors have completed the present invention as a result of studies to solve these problems. That is, the present invention comprises a block A made of a polymer having a glass transition temperature of 50 ° C. or lower and a block B made of a polymer having a glass transition temperature of 10 ° C. or higher, and the weight ratio between the block A and the block B is 1 A block copolymer of ABA type having a:
0.3 to 10 wt% is the general formula (formula 3) and / or the general formula (formula 4)

[0007]

[Chemical 3] (However, in the formula, R ¹ represents hydrogen or a methyl group.)

[0008]

CH ₂ ═CH—OR ² (wherein R ² is a linear or branched alkyl group having 1 to 13 carbon atoms, a cycloalkyl group having 1 to 10 carbon atoms, an alkenyl group, an alkynyl group, An ABA type block copolymer characterized by being a polymer of a vinyl monomer represented by an aralkyl group, a (substituted) phenyl group, a haloalkyl group, an oxyalkyl group, an aminoalkyl group and a thioalkyl group). It is an electrophotographic toner composition as a main constituent.

In the ABA type block copolymer, which is a feature of the present invention, the A block has a sea structure and the B block has an island structure.
By introducing a polymer of isobornyl vinylate and / or vinyl ether into the A block which is the sea, the blocking resistance and the high temperature offset resistance are further improved, and the B block is imparted with a low temperature fixing property. It is a thing.

The A block constituting the ABA type block copolymer is composed of isobornyl vinylates and / or vinyl ethers and the following styrene and / or acrylic and / or methacrylic monomers and / or
Alternatively, it is synthesized from a vinyl monomer containing a carboxyl group and has a glass transition temperature (Tg) of 50 ° C. or higher. In addition, the B block is also synthesized from the same type of styrene-based and / or acrylic-based and / or methacrylic-based monomer used for the A block and / or vinyl monomer containing a carboxyl group, and may be polyfunctional if necessary. It has a glass transition temperature (Tg) of 10 ° C. or less and is synthesized by using a polar ethylene monomer. Further, the polymer of isobornyl vinylate and / or vinyl ether must be contained in the A block in an amount of 0.3 to 10% by weight. When the content in the A block is 0.3% by weight or less, the offset resistance and the blocking resistance, which are the roles of the A block, cannot be obtained in the high-speed / low-calorie copying machine.
If it is more than wt%, excellent offset resistance can be obtained,
The fixing property is inferior, which is not preferable. Further, the block B may have a glass transition temperature (Tg) of 10 ° C. or less, but if a polyfunctional ethylene-based monomer is used in an amount of 0.3 to 10% by weight in order to further improve low temperature fixability. Good. The presence of the polyfunctional ethylene-based monomer improves the elasticity of the B block portion and improves the low temperature fixability. If the amount used is less than 0.3% by weight, there is no improvement effect on the low-temperature fixability, and if the amount used is 10% by weight or more, the low-temperature fixability deteriorates. Further, in order to keep the balance of various physical properties required for the toner composition such as low temperature fixing property, anti-offset property and anti-blocking property, the ratio of A block to B block of the ABA type block copolymer is 1: 0.05-1. :
Must be 2000. If it deviates from this range, the balance of various physical properties will deteriorate.

Examples of isobornyl vinylates contained in the A block include isobornyl acrylate and isobornyl methacrylate, which may be used alone or as a mixture. Examples of vinyl ethers include alkyl vinyl ethers (R =
Methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl,
Isopentyl, 1,2-dimethylpropyl, n-hexyl, isohexyl, 2-ethylbutyl, 1,3-dimethylbutyl, n-
Heptyl, isoheptyl, n-octyl, 1-methylheptyl, 2-ethylhexyl, n-nonyl, 2-methyloctyl,
n-decyl, 1-pentylhexyl, 4-ethyl-1-methyloctyl, n-dodecyl, n-tetradecyl, n-hexadecyl, n-octadecyl, n-eicosyl, n-docosyl, etc.), cycloalkyl vinyl ethers (R = Cyclohexyl, 4-n-butylcyclohexyl, 4- [3- (2,2,4-trimethyl) pentyl] -cyclohexyl, 4-n-dodecylcyclohexyl, 4-cyclohexylcyclohexyl, cyclohexylmethyl, 1-cyclohexylethyl, 2 -Cyclohexylethyl, 2-decahydronaphthyl, terpineyl, menthyl, bornyl, isobornyl, etc.), alkenyl vinyl ethers (R = vinyl, allyl, isopropenyl, 1-methylallyl, 2-methylallyl (methallyl), 3-methyl-2-) Butenyl, 2-pentenyl, cis-1-methyl-2-butenyl, trans-1-methyl-2-butenyl, 3-methyl-2 -Butenyl, 1-ethylallyl, 1,3-dimethyl-2-
Butenyl, 1-methyl-2-hexenyl, 2-cyclopente-1
-Nyl, 2-cyclohexen-1-yl, dicyclopentenyl, 1-octahydronaphthyl, 1- (cyclopent-1-enyl) methyl, 1- (cyclopent-1-enyl) ethyl, etc.), alkynyl vinyl ether (R = ethynyl, propynyl-nyl, propyn-2-nyl, but-1-ynyl, buty-2
-Nyl, but-3-ynyl, 1-methylbut-3-ynyl, 1,1-dimethylprop-2-ynyl, hex-1-ynyl, hex-3-enyl, hept-1-ynyl, hept-3- Nil, 7-methyloctyl
-3-nyl etc.), aralkyl vinyl ethers (R = benzyl, p-methylbenzyl, p-methylbenzyl, p-phenylbenzyl, 1-phenylethyl, 2-phenylethyl,
2-phenylpropyl, 3-phenylpropyl, 1,1-dimethylbenzyl, benzhydryl, cinnamyl, 1-methylcinnamyl, 3-methylcinnamyl, 3-phenylcinnamyl, 2-phenylallyl, 1-methyl-2- Phenylallyl,
3-phenylprop-2-yl etc.),

(Substituted) phenyl vinyl ethers (R =
Phenyl, o-tolyl, m-tolyl, p-tolyl, pt-butyl, mesityl, 2-methyl-5-isopropylphenyl, 5-
Methyl-2-isopropylphenyl, p-isohexylphenyl, p-isooctylphenyl, p-vinylphenyl, o-
Biphenyl, p-biphenyl, p-fluorophenyl, o-chlorophenyl, m-chlorophenyl, p-chlorophenyl,
2,4-dichlorophenyl, 2,3,4-trichlorophenyl, 2,
4,6-trichlorophenyl, pentachlorophenyl, 2-chloro-4-nitrophenyl, o-bromophenyl, m-bromophenyl, p-bromophenyl, 2,6-dibromo-4-nitrophenyl, p-iodophenyl, o-methoxyphenyl, m-
Methoxyphenyl, p-methoxyphenyl, o-ethoxyphenyl, m-ethoxyphenyl, o-nitrophenyl, m-nitrophenyl, p-nitrophenyl, 2,4-dinitrophenyl, p-benzyloxyphenyl, etc.), haloalkyl vinyl Ethers (R = trifluoromethyl, 1-chloroethyl, 2-chloroethyl, 2-bromoethyl, 2-iodoethyl, 2-fluoroethyl, 2,2,2-trifluoroethyl, 3-
Chloropropyl, 1,3,3,3-tetrachloropropyl, 3-bromopropyl, 3-iodopropyl, 3-fluoropropyl, 1-H, 1-H perfluoropropyl, 4-chlorobutyl, 3-bromobutyl, 4 -Bromobutyl, 3-iodobutyl, 4-iodobutyl, 4-fluorobutyl, 1-H, 1-H perfluorobutyl, 6-chlorohexyl, 6-bromohexyl, 6-iodohexyl, 1-H, 1-H per Fluorohexyl, cis, trans-2-bromovinyl, 2-chloroallyl, etc.),

Oxyalkyl vinyl ethers (glycol vinyl ethers) (R = 2-hydroxyethyl, 3-hydroxypropyl, 4-hydroxybutyl, 5-hydroxypentyl, diethylene glycol mono, triethylene glycol mono, 2-methoxyethyl, 2-ethoxy ethyl,
2-phenoxyethyl, 2- (4-methylphenoxy) ethyl, 2- (2,5-dimethylphenoxy) ethyl, 2- (4-n-butylphenoxy) ethyl, 2- (4-isobutylphenoxy) ethyl, 2 -(4-t-Butylphenoxy) ethyl, 2-
(4-octylphenoxy) ethyl, 2- (4-n-dodecylphenoxy) ethyl, 2- (4-n-octadecylphenoxy)
Ethyl, 2- (4-chlorophenoxy) ethyl, 2- (2-naphthoxy) ethyl, acetoxymethyl, 2-acetoxyethyl, 4-ethoxybutyl, 2-vinyloxyethyl, 2-allyloxyethyl, 2- (2-chloro Aryloxy) ethyl, 2- (2-
Methylallyloxy) ethyl, 2- (3-methylallyloxy)
Ethyl, 2-furfuryloxyethyl, 3-vinyloxypropyl, 5-vinyloxypentyl, 4-vinyloxycyclohexyl, 10-vinyloxydecyl, 12-vinyloxyoctadecyl, diethylene glycol methyl, diethylene glycol ethyl, 2- (2-chloroethoxy ) Ethyl, 2- (2-bromoethoxy) ethyl, 2- (2-iodoethoxy) ethyl, triethylene glycol ethyl, 1,2-methyleneglycerin, 1,2-ethylideneglycerin, 1,2-isopropylideneglycerin, 1,2-benzylidene glycerin, diacent glucose, diacent fructose, etc.), aminoalkyl vinyl ethers (R = 2-aminoethyl, 2-
Dimethylaminoethyl, 2-diethylaminoethyl, 2-n-
Butylaminoethyl, 2-di-n-butylaminoethyl, 5-
Diethylaminopentyl, diethanolamine mono, 2-
Phenylaminoethyl, 2-m-tolylaminoethyl, 2-p-
Chlorophenylaminoethyl, 2-diphenylaminoethyl, 2-N-ethyl-N-phenylaminoethyl, 2-Nn-butyl-n-phenylaminoethyl, 2-pyrrolidylethyl, 2-
Hexamethyleneiminoethyl, 2-perhydrocarbazoylethyl, etc.), thioalkyl vinyl ethers (R
= 2-methylthioethyl, 2-ethylthioethyl, 2-n-propylthioethyl, 2-n-butylthioethyl, 2-n-hexylthioethyl, 2-n-heptylthioethyl, 2-allylthioethyl, 2-phenylthioethyl, 2-benzylthioethyl,
3-ethylthiopropyl, 3-n-propylthiopropyl, 3-
nn-butylthiopropyl, 3-neopentylthiopropyl, 3-n-heptylthiopropyl, 3-phenylthiopropyl, 3-benzylthiopropyl, etc., other vinyl ethers (R = 1-methyl-3-oxobutyl, Carbomethoxymethyl, 3-tetrahydrofuryl, 2,5-dimethyltetrahydrofuryl-3-, 4-methoxytetrahydrofuryl-3
-, Tetrahydrofurfuryl, furfuryl, 2-β-pyridylethyl, 2-cyanoethyl, 2-nitrobutyl, 2-nitro-2-methylpropyl, 2,2-dimethyl-2-isocyanatoethyl, 3- (methyldiethylsilyl) ) Propyl and the like), which are used alone or as a mixture. Further, these isobornyl vinylates and vinyl ethers can be used in combination.

Specific examples of the polyfunctional ethylene-based monomer that can be used in the B block include 2,2-bis (4-acryloxypolyethoxyphenyl) propane,
1,3-butylene glycol diacrylate, 1,5-pentanediol diacrylate, neopentyl glycol diacrylate, 1,6-hexanediol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene Glycol diacrylate,
Polyethylene glycol # 400 diacrylate, polyethylene glycol # 600 diacrylate, polypropylene glycol diacrylate, N, N'-methylenebisacrylamide, pentaerythritol triacrylate, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, etc. Polymer, 1,4-butanediol diacrylate, ethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, neopentyl glycol dimethacrylate, 1,6-hexanediol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate , Polyethylene glycol # 200 dimethacrylate, polyethylene glycol # 400 dimethacrylate, polyethylene glycol # 600 Dimethacrylate, dipropylene glycol dimethacrylate, polypropylene glycol dimethacrylate, trimethylolethane trimethacrylate, trimethylolpropane trimethacrylate, 2,2-bis (4-methacryloxypolyethoxyphenyl) propane, aluminum methacrylate, methacryl Methacrylic acid-based monomers such as zinc oxide, calcium methacrylate, magnesium methacrylate, etc., as well as diallyl phthalate, triallyl cyanurate,
Examples include triallyl isocyanurate, triallyl trimellitate, diallyl chlorendate, ethylene glycol diglycidyl ether acrylate, and divinylbenzene.

Specific examples of the vinyl monomer for the B block (soft component) usable in the present invention include methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, acrylic acid. Octyl, cyclohexyl acrylate, lauryl acrylate, stearyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, α-chloromethyl acrylate, benzyl acrylate, furfuryl acrylate, acrylic There are acrylic acid esters such as acid tetrahydrofurfuryl, acrylic acid hydroxyethyl, acrylic acid hydroxybutyl, acrylic acid dimethylaminomethyl ester, and acrylic acid dimethylaminoethyl ester.

Specific examples of the vinyl monomer for the A block (hard component) include methyl methacrylate, ethyl methacrylate, propyl methacrylate and n-methacrylate.
Butyl, isobutyl methacrylate, octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, cyclohexyl methacrylate, lauryl methacrylate, stearyl methacrylate, benzyl methacrylate. Methacrylic acid esters such as furfuryl methacrylate, tetrahydrofurfuryl methacrylate, hydroxyethyl methacrylate, hydroxybutyl methacrylate, dimethylaminomethyl methacrylate ester, and dimethylaminoethyl methacrylate ester; o-methylstyrene, m-
Methylstyrene, p-methylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, pn-butylstyrene, pt-butylstyrene, pn-hexylstyrene, pn-octylstyrene, p- n-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene, p-methoxystyrene, p-phenylstyrene,
3,4-dichlorostyrene, α-methylstyrene, p-
Aromatic vinyl monomers such as chlorostyrene and styrene;
Vinylnaphthalene; Ethylenically unsaturated monoolefins such as ethylene, propylene, butylene, isobutylene; Vinyl esters such as vinyl chloride, vinyl bromide, vinyl fluoride, vinyl acetate, vinyl propionate; Dibutyl maleate, dioctyl maleate Unsaturated dibasic acid dialkyl esters such as dibutyl fumarate and dioctyl fumarate; acrylic acid or methacrylic acid derivatives such as acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, N-substituted methacrylamide, methacrylamide propane sulfonic acid; vinylmethyl Vinyl ethers such as ether, vinyl ethyl ether and vinyl isobutyl ether; vinyl keto such as vinyl methyl ketone, vinyl hexyl ketone and methyl isopropenyl ketone Unsaturated carboxylic acids such as acrylic acid, methacrylic acid and cinnamic acid; maleic acid,
Unsaturated dicarboxylic acids such as maleic anhydride, fumaric acid and itaconic acid; monomethyl maleate, monoethyl maleate, monobutyl maleate, monooctyl maleate, monomethyl fumarate, monoethyl fumarate, monobutyl fumarate, monooctyl fumarate, etc. Unsaturated dicarboxylic acid monoesters; N-vinylpyrrole, N
-N-vinyl compounds such as vinylcarbazole, N-vinylindole and N-vinylpyrrolidene.

The ABA type block copolymer of the present invention is preferably synthesized by using an initiator having a plurality of dithiocarbamate groups. The synthesis itself of an ABA type block copolymer using this initiator having a dithiocarbamate group is already known (for example, Polymer Preprints, Japa).
n, 32 , 1047 (1983)). The ABA type block copolymer of the present invention having an intermediate block B consisting of a specific residue and both terminal blocks A consisting of a specific residue utilizing such a reaction known per se is To be described next 2
Synthesized by stepwise polymerization. First, as the first-stage polymerization, the general formula (Formula 5)

[0018]

[Chemical 5] (In the formula, R ³ represents a hydrocarbon group having 1 to ³ carbon atoms.
Two R ³ may be the same or different. R ⁴
Represents a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms. Two R ⁴ may be the same or different. ) Using a dithiocarbamate compound represented by
Photopolymerize with a mixture of polyfunctional ethylene monomer and other vinyl monomer. This gives the general formula (Formula 6)

[0019]

[Chemical 6] (In the formula, R ³ and R ⁴ are as described above. M ¹ represents a polyfunctional ethylene-based monomer group and another vinyl monomer group.) A dithiocarbamate-modified flexible resin at both terminals A component ethylene polymer is obtained. Further, in the second stage polymerization, such an ethylene polymer having dithiocarbamates at both ends as the soft component ethylene polymer itself is used as an initiator, and a monomer for M ² (hard component monomer), that is, a methacrylic acid ester, a maleimide or an aromatic group is used. Photopolymerize the vinyl derivative. Thereby, an ABA type block copolymer can be manufactured.

It is general that these first-stage and second-stage polymerizations are all carried out by photopolymerization using ultraviolet rays having a wavelength necessary for decomposition / radical generation of the dithiocarbamate, for example, 300 to 500 nm. is there. If the light reaches the dithiocarbamate group, which is the initiation site in both the first and second stages of polymerization, this polymerization can be performed in any of bulk, solution, suspension, dispersion, slurry and emulsion states. You can go in. In the case of producing by the solution polymerization method in both the first-stage and second-stage polymerization, the solvent is 300 to 500
It is preferable to use a solvent that does not have characteristic absorption in ultraviolet rays of nm, has a small chain transfer constant, and can dissolve the monomer and the polymer well. Examples of such a preferable solvent include benzene, toluene, xylene, ethylbenzene, acetone, methyl ethyl ketone, ethyl acetate, dimethylformamide, isopropyl alcohol, butanol, hexane, heptane and the like. Further, the polymerization atmosphere, the polymerization temperature is preferably the same conditions as in ordinary radical polymerization,
Specifically, 10 to 15 in an inert gas such as nitrogen or argon.
A temperature of 0 ° C. is preferred. It is also possible to replace the terminal of the block copolymer by adding a reagent having a large chain transfer constant, such as thiol, while irradiating the synthesized block copolymer with ultraviolet rays.

The binder resin used in the present invention is ABA.
The block copolymer may be contained, but in order to exert the characteristics of the block copolymer more effectively, the block copolymer is contained in an amount of 25 parts by weight or more, preferably 50 parts by weight or more. Is desirable. The resin mixed with the block copolymer is preferably polystyrene resin, styrene-acrylic resin, or polyester resin. The amount of the binder resin of the present invention in the toner composition is usually 50 to 95 parts by weight. Further, if necessary, in a range that does not impair the effects of the present invention, the binder resin mixture, for example, polyvinyl chloride resin, polyolefin resin, polyester resin, polyvinyl butyral, polyurethane resin, polyamide resin, rosin, terpene resin, phenol Resin, epoxy resin, paraffin wax, polyolefin wax, etc. may be added.

A colorant is usually used in the electrophotographic toner composition using the block copolymer of the present invention. Examples of the colorant used include black pigments such as carbon black, acetylene black, lamp black, and magnetite, yellow lead, yellow iron oxide, Hansa Yellow G, quinoline yellow lake, permanent yellow, NCG molybdenum orange, vulcan orange, indance. Len,
Brilliant Orange GK, Bengal, Brilliant Carmine 6B, Frizarin Lake, Fast Violet B, Cobalt Blue, Alkali Blue Lake, Phthalocyanine Blue, Metal Complex of Monoazo Dye, Fast Sky Blue, Pigment Green B, Malachite Green Lake, Oxidation Known pigments such as titanium and zinc white can be used. The amount is usually 5 to 3 per 100 parts by weight of the binder resin.
00 parts by weight.

In the toner composition of the present invention, for example, known charge adjusting agents such as nigrosine, quaternary ammonium salts, metal-containing azo dyes, metal salts of fatty acids, pigment dispersants, offset preventing agents, etc. are appropriately selected and added. However, the toner can be prepared by a known method. That is, after premixing a mixture containing the above various additives with a Henschel mixer, heating and melting and kneading with a kneader such as a kneader, after cooling,
After coarse pulverization and fine pulverization using a jet pulverizer, classification is performed by an air classifier, and particles in the range of 8 to 20 μ are usually collected to obtain a toner. Magnetic powder may be included in order to obtain a magnetic toner. Such magnetic powders include ferromagnetic substances magnetized in a magnetic field, powders of iron, nickel, cobalt, etc., or alloys such as magnetite, ferrite, etc. The ratio of the magnetic powders to the toner weight is 15 to 70 parts by weight is preferred. Further, in the present invention, a releasing agent as described below may be appropriately used during polymerization or during melting / kneading. The release agent referred to here is a substance that acts on the heat roller during fixing to reduce friction, improve releasability, or improve fluidity during melting. For example, paraffin wax, high-grade (saturated) Straight-chain) fatty acids (12 carbon atoms
~ 50), higher alcohols (C8-C32), fatty acid metal salts, fatty acid amides, metal soaps, polyhydric alcohols and the like can be used. Colloidal silica, fatty acid metal salts and the like may be used as the powder fluidity modifier in the toner of the present invention. Further, for the purpose of increasing the amount, a filler such as calcium carbonate or fine powder silica may be blended in the toner in an amount of 0.5 to 20 parts by weight. Further, in order to prevent the toner particles from coagulating with each other and improve the powder fluidity, a flow improver such as Teflon fine powder may be added. The toner using the polymer of the present invention as a binder resin can be applied to all known developing methods. For example, a two-component developing method such as a cascade method, a magnetic brush method or a microtoning method; a one-component developing method containing a magnetic material such as a conductive one-component developing method, an insulating one-component developing method or a jumping developing method; powder clouding. And a fur brush method; a non-magnetic one-component developing method in which the toner is carried on a toner carrier by electrostatic force and conveyed to a developing section.

[0024]

EXAMPLES The present invention will now be described in more detail with reference to examples, but the present invention is not limited to these examples. In the following, “parts” means parts by weight unless otherwise specified. Production Example 1 1 part of p-xylylene bis (N, N-diethyldithiocarbamate) (hereinafter abbreviated as XDC), 95 parts of butyl acrylate, polyethylene glycol # 400 diacrylate
Dissolve it in 5 parts of the mixture and put it in a 1 liter container made of Pyrex glass, sufficiently replace the residual gas in the container with nitrogen and then seal it, and then close it with a 400 W ultraviolet lamp (Toshiba H40
It was irradiated with ultraviolet light for about 10 hours at a position 15 cm away from a 0 L mercury lamp). After the irradiation, when the residual butyl acrylate monomer and polyethylene glycol # 400 diacrylate monomer in the polymer produced by gas chromatography were measured, the residual amount was 1.2%. That is, the conversion rate of the butyl acrylate monomer and the polyethylene glycol # 400 diacrylate monomer was 98.8%. Also,
XD in polymer produced by liquid chromatography
When C was measured, it was not detected at all. Therefore, it is considered that all the XDCs were added to the butyl acrylate / polyethylene glycol # 400 diacrylate copolymer, and the product was a dithiocarbamate-terminated polymer containing a flexible polymer block. Further, the molecular weight of the produced polymer was measured by gel permeation chromatography, and the number average molecular weight (Mn) in terms of polystyrene was 67500, and the weight average molecular weight (M
w) was 135600. Then the resulting polymer
100 parts in the same glass container as above, 95 parts styrene,
5 parts of isobornyl acrylate and 30 parts of toluene were added, these were mixed sufficiently, and ultraviolet rays were irradiated for 10 hours under the same conditions as above to carry out polymerization.

The amounts of styrene monomer, isobornyl acrylate monomer and butyl acrylate monomer, and polyethylene glycol # 400 diacrylate monomer remaining in the produced polymer were measured for the produced solution by gas chromatography. , 0.9%, 0.2%, 0.3% respectively
And 0.1%. Therefore, the final monomer conversion was 98.5%. This product solution was added with 10 L of n-
Purification by reprecipitation using hexane and drying under reduced pressure. The obtained polymer has a molecular weight of Mn of 83400 and Mw of 186500.
Met. The molecular structure of this polymer was examined by the following thermodynamic method and morphological observation.
It was found to be an ABA type resin having a hard polymer block A having a g of 102 ° C. and a soft polymer block B having a Tg of −51 ° C.

Thermodynamic Method The calorific value of the produced polymer was measured using a differential scanning calorimeter (hereinafter abbreviated as DSC).
Tg was observed at 102 ° C. and no other mutation points could be found. The Tg of -51 ° C and 102 ° C are derived from the butyl acrylate / polyethylene glycol # 400 diacrylate copolymer block and the styrene / isobornyl acrylate copolymer block, respectively. Therefore, it was proved that this resin is not a random copolymer or a compatible polymer blend, but a block copolymer or an incompatible polymer blend. Therefore, in order to determine whether the produced resin is a block copolymer or an incompatible polymer blend, the following morphological observation was further performed.

Morphological observation When the morphology of the produced polymer was observed using a phase contrast microscope and a transmission electron microscope (hereinafter abbreviated as TEM), it showed a microphase-separated structure and a domain diameter of 50.
It was less than 0 angstrom. Such a microphase-separated structure is characteristic of block copolymers [Akiyama, Inoue, Nishi, "Polymer Blend" (1981) 1
See page 69 below. For comparison, a butyl acrylate / polyethylene glycol # 400 diacrylate copolymer having the same composition as in Production Example 1 having a Mn of 70100 and Mw of 156200 synthesized by the same apparatus as in Production Example 1 using XDC was used for comparison. 75 parts of polymer, Mn is 9500, Mw is 194
The same as above was prepared by kneading 25 parts of a styrene / isobornyl acrylate copolymer having the same composition as in Production Example 1 of 00 with a Labo Plastomill at 200 ° C. and 100 rpm for 5 minutes. Morphological observation revealed a macrodomain structure with a domain diameter of 100 microns or more. This is a typical incompatible polymer blend, and it is clear that the above-mentioned polymer produced is a block copolymer. Considering that the initiator used for the polymerization is a dithiocarbamate-terminated polymer at both ends,
The resulting polymer is a butyl acrylate / polyethylene glycol # 400 diacrylate copolymer B having a Tg of -51 ° C,
It was confirmed that the polymer was an ABA type block copolymer composed of styrene / isobornyl acrylate copolymer A having a Tg of 102 ° C. The produced polymer was treated with acetone to extract each block, and the blocking rate was calculated. The blocking rate was 98.4%. This is referred to as block copolymer 1.

Production Example 2 A block polymer was synthesized in the same manner as in Example 1 except that 95 parts of methyl methacrylate was used instead of 95 parts of styrene used in Production Example 1. Regarding the molecular weight of the obtained polymer, the number average molecular weight (Mn) was 73800 and the weight average molecular weight (Mw) was 167800. The structure was determined using the same method as in Production Example 1. Derived from butyl acrylate / polyethylene glycol # 400 diacrylate copolymer and methyl methacrylate / isobornyl acrylate copolymer depending on calorimetric measurement -51 ° C and 105 ° C
Other than Tg of No. could not be observed. In addition, it was confirmed from the morphological observation that it was a block copolymer. From the above results and the fact that the initiator is bifunctional, this product is an ABA consisting of butyl acrylate / polyethylene glycol # 400 diacrylate copolymer block B and methyl methacrylate / isobornyl acrylate copolymer block A.
It was found to be a type block copolymer. This is referred to as block copolymer 2.

Production Example 3 Instead of 95 parts of methyl methacrylate used in Production Example 2,
A block polymer was synthesized in the same manner as in Production Example 2 except that a mixed solution of 50 parts of methyl methacrylate and 45 parts of N-phenylmaleimide was used. The molecular weight of the obtained polymer is
Mn was 83800 and Mw was 175900. The structure was determined using the same method as in Production Example 1. Butyl acrylate / polyethylene glycol depending on calorimetry
Nothing other than the Tg of -51 ° C and 182 ° C derived from the # 400 diacrylate copolymer and the methyl methacrylate / N-phenylmaleimide / isobornyl acrylate copolymer was observed. In addition, it was confirmed from the morphological observation that it was a block copolymer. From the above results and the fact that the initiator is bifunctional, the product is butyl acrylate / polyethylene glycol # 400 diacrylate copolymer block B and methyl methacrylate / N-phenylmaleimide / isobornyl acrylate copolymer. It was found to be an ABA type block copolymer consisting of block A. This is referred to as block copolymer 3.

Production Example 4 A block polymer was synthesized in the same manner as in Production Example 1 except that 5 parts of divinylbenzene was used instead of 5 parts of polyethylene glycol # 400 diacrylate used in Production Example 1. As for the molecular weight of the obtained polymer, Mn was 64600 and Mw was 135900. The structure was determined using the same method as in Production Example 1. Derived from butyl acrylate / divinylbenzene copolymer and styrene / isobornyl acrylate copolymer depending on calorimetric measurement -57 ° C
And no Tg of 102 ° C was observed. In addition, it was confirmed from the morphological observation that it was a block copolymer. Based on the above results and the fact that the initiator is bifunctional, this product is an ABA type block copolymer consisting of butyl acrylate / divinylbenzene copolymer block B and styrene / isobornyl acrylate copolymer block A. It turned out to be. This is referred to as block copolymer 4.

Production Example 5 A block polymer was synthesized in the same manner as in Production Example 1 except that 5 parts of n-butyl acrylic ether was used instead of 5 parts of isobornyl acrylate used in Production Example 1. The obtained polymer has a molecular weight of Mn of 74900 and Mw of
It was 157300. The structure was determined using the same method as in Production Example 1. According to the calorimetric measurement, only Tg of -51 ° C. and 114 ° C. derived from butyl acrylate / polyethylene glycol # 400 diacrylate copolymer and styrene / n-butyl acrylic ether copolymer could be observed. In addition, it was confirmed from the morphological observation that it was a block copolymer. Based on the above results and the fact that the initiator is bifunctional, this product is an ABA type consisting of butyl acrylate / polyethylene glycol # 400 diacrylate copolymer block B and styrene / n-butyl acrylic ether copolymer block A. It was found to be a block copolymer. This is referred to as a block copolymer 5.

Production Example 6 A block polymer was synthesized in the same manner as in Production Example 1 except that polyethylene glycol # 400 diacrylate was not used. The molecular weight of the obtained polymer was such that Mn was 7
It was 4300 and Mw was 156700. 1 The confirmation of the structure is
The same method as in Production Example 1 was used. Derived from butyl acrylate polymer and styrene-isobornyl acrylate copolymer by calorimetry at -54 ° C and 102 ° C.
Nothing other than Tg at ° C could be observed. In addition, it was confirmed from the morphological observation that it was a block copolymer. From the above results and the fact that the initiator is bifunctional, it was found that this product is an ABA type block copolymer composed of the butyl acrylate polymerization block B and the styrene / isobornyl acrylate copolymer block A. . This is referred to as block copolymer 6.

Production Example 7 Production Example 1 except that no isobornyl acrylate was used.
A block polymer was synthesized in the same manner as in. As for the molecular weight of the obtained polymer, Mn was 67500 and Mw was 143900. The structure was determined using the same method as in Production Example 1. According to the calorimetric measurement, only Tg at -51 ° C and 100 ° C derived from butyl acrylate / polyethylene glycol # 400 diacrylate copolymer and styrene polymer could be observed. In addition, it was confirmed from the morphological observation that it was a block copolymer. The above results and 2 initiators
This product is butyl acrylate.
AB consisting of polyethylene glycol # 400 diacrylate copolymer block B and styrene polymer block A
It was found to be an A type block copolymer. This is referred to as block copolymer 7.

Production Example 8 Isobornyl acrylate and polyethylene glycol # 4
A block polymer was synthesized in the same manner as in Production Example 1 except that 00 diacrylate was not used. Regarding the molecular weight of the obtained polymer, Mn was 63800 and Mw was 132400. The structure was determined using the same method as in Production Example 1. According to calorimetric measurements, only Tg of -54 ° C and 100 ° C derived from butyl acrylate polymer and styrene polymer could be observed. In addition, it was confirmed from the morphological observation that it was a block copolymer. From the above results and the fact that the initiator is bifunctional, it was revealed that this product was an ABA type block copolymer composed of a butyl acrylate polymer block B and a styrene polymer block A. This is referred to as a block copolymer 8. Table 1 shows the physical properties of the block copolymers obtained by the above production examples.

[0035]

[Table 1]

2. Production and evaluation of toner 100 parts of ABA type block copolymer and carbon black (M
A-100 (manufactured by Mitsubishi Kasei Co., Ltd.) 10 parts, polypropylene wax 5 parts, and Nigrosine dye 1 part as a charge control agent were premixed with a Henschel mixer, and then using a twin-screw kneader, 1
After kneading at 70 ℃, cooling, coarse crushing, fine crushing,
Further, classification was carried out with an air classifier to obtain toner of 8 to 20 μm. Using the above toner, the fixability, offset property, image quality stability, etc. were evaluated. The fixing property and the offset property were used for a copying machine modified so that the heat roll temperature of a commercial copying machine can be arbitrarily changed. Next, an evaluation method will be shown. 70% fixing temperature; 2 cm x 2 cm solid black part of the toner layer on the image quality was applied with a gakushin type friction fastness tester (manufactured by Daiei Kagaku Seiki Co., Ltd.) with a load of 125 g / cm ² and sand eraser. The minimum heat roll temperature was required so that the weight residual ratio of the toner layer after rubbing 50 times exceeded 70%. High temperature offset temperature: The temperature of the hot roll was increased to be the temperature at which offset began to occur. Blocking property: 100 g of toner was placed in a polybin, tapped, kept at 50 ° C. for 50 hours, then returned to room temperature, transferred onto a paraffin paper, and visually judged according to the following judgment criteria. ◎ No blocking at all. ○ There is some blocking, but there is no problem in practical use. △ Very blocking. × Almost one lump. Image quality (fog): 100th and 1st in continuous copying
Compare the white background of the 0,000th sheet, and if the white background is heavily soiled due to the effects of scattering, etc., ○ (good),
It was judged as Δ (stains can be confirmed with a magnifying glass of 30 times) and × (stains can be confirmed with the naked eye). Table 2 shows specific evaluation results.

[0037]

[Table 2]

[0038]

According to the method of the present invention, a stable and high-quality image can always be obtained even in a low heat fixing copying machine which cannot be solved by the conventional technique. That is, the toner composition using the resin of the present invention has a low lower limit fixing temperature and a wide non-offset temperature region, and has excellent performance as a toner composition for electrophotography.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kenji Uchiyama 1190 Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa Mitsui Toatsu Chemicals, Inc. (72) Katsuo Uramoto 1190 Kasama-cho, Sakae-ku, Yokohama, Kanagawa Mitsui Toatsu Chemical Co., Ltd. (72) Inventor Tamami Fukui 1190 Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa Mitsui Toatsu Chemical Co., Ltd.

Claims (2)

[Claims] 1. A block A made of a polymer having a glass transition temperature of 50 ° C. or lower and a block B made of a polymer having a glass transition temperature of 10 ° C. or higher, and the weight ratio of the block A to the block B is 1 :. 0.05 to 1: 2000 ABA type block copolymer, 0.3 to 10 wt% in block A
% Is the general formula (Formula 1) and / or the general formula (Formula 2) (Wherein R ¹ represents hydrogen or a methyl group) CH ₂ ═CH—OR ² (wherein R ² is a linear or branched alkyl group having 1 to 13 carbon atoms, A vinyl-based monomer represented by a cycloalkyl group having 1 to 10 carbon atoms, an alkenyl group, an alkynyl group, an aralkyl group, a (substituted) phenyl group, a haloalkyl group, an oxyalkyl group, an aminoalkyl group, and a thioalkyl group. A toner composition for electrophotography, which comprises an ABA type block copolymer as a main constituent, which is a polymer. 2. A block B of an ABA type block copolymer
The electrophotographic toner composition according to claim 1, wherein 0.3 to 10 wt% of the polyfunctional ethylene monomer is a polymer.