JPH02168276A - Liquid developer for electrostatic photography - Google Patents

Abstract

PURPOSE:To obtain a liquid developer for electrostatic photography having improved redispersibility, preservability, stability, reproducibility of picture image, and fixing effect by constituting the developer of particles of a copolymer resin obtd. by a polymn. reaction of a soln. contg. a specified monofunctional monomer and an oligomer. CONSTITUTION:The liquid developer is constituted of particles of a copolymer resin obtd. by polymerizing a monofunctional monomer, which is soluble in a nonaqueous solven but becomes insoluble by the polymn. with a soln. contg. an oligomer having <=10<4> number average mol.wt. formed by bonding only polar groups such as COOH group, sulfo group, OH group, phosphone group, etc. to one terminal of a principal chain of a polymer consisting of recurrent units expressed by the formula I, in the presence of a resin which is soluble in a nonaq. solvent and contains no grafting group polymerizing with the monomer. In the formula I, X is -COO-, -OCO-, CH2OCO-, -CH2COO-, -O-, -SO2-, etc.; Y is a 1-22C hydrocarbon group; each a<1> ad a<2> is an H atom, halogen atom, cyano group, 1-8C hydrocarbon group, etc. Thus, a liquid developer having improved dispersion stability, redispersibility, and fixing effect, is obtd.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention is applicable to electrical resistance of 10'ΩCl11 or more and dielectric constant of 3.5.
The present invention relates to an electrostatographic liquid developer comprising at least a resin dispersed in the following carrier liquid, and particularly relates to a liquid developer having excellent redispersibility, storage stability, stability, image reproducibility, and fixing ability.

(Prior Art) General liquid developers for electrophotography include organic or inorganic pigments or dyes such as carbon black, nigrosine, phthalocyanine blue, acrylic resin, rosin, etc.
Natural or synthetic resins such as synthetic rubber are dispersed in highly insulating and low dielectric constant liquids such as petroleum-based aliphatic hydrocarbons, and polymers containing metal soap, lecithin, linseed oil, higher fatty acids, and vinyl pyrrolidone are also produced. and a polarity control agent.

In such developers, the resin is dispersed as insoluble latex particles with a diameter of several nanometers to several hundred nanometers, but in conventional liquid developers, a soluble dispersion stabilizing resin, a polarity control agent, and insoluble latex particles are dispersed. Due to insufficient bonding, the soluble dispersion stabilizing resin and polarity control agent were likely to diffuse into the solution. For this reason, there has been a drawback that the soluble dispersion stabilizing resin is detached from the insoluble latex particles due to long-term storage or repeated use, causing the particles to settle, aggregate, or accumulate, and the polarity to become unclear. Furthermore, since particles that have aggregated and accumulated are difficult to redisperse, they remain attached to various parts of the developing machine, leading to problems with the developing machine such as staining of the image area and clogging of the liquid feed pump.

In order to improve these drawbacks, a means for chemically bonding a soluble dispersion stabilizing resin and insoluble latex particles has been devised and disclosed in US Pat. No. 3,990,980 and the like. However, although the stability of these liquid developers against natural sedimentation of particles has improved to some extent, it is still not sufficient, and when used in an actual developing device, the toner adhering to various parts of the device may cause a coating film. The redispersion stability is insufficient for practical use, such as solidification, making it difficult to redisperse and causing equipment failure and staining of copied images. In the method for producing resin particles described above, in order to produce monodispersed particles with a narrow particle distribution, there are significant restrictions on the combination of the dispersion stabilizer used and the monomer to be insolubilized; The particles had a wide particle size distribution containing a large amount of coarse particles, or the particles had a polydisperse particle size with two or more average particle sizes. Furthermore, it is difficult to obtain a desired average particle size with monodisperse particles having a narrow particle size distribution, and large particles of 1 mm or more or very fine particles of 0.1 mm or less are formed. Furthermore, there are problems in that the dispersion stabilizer used must be manufactured through a complicated and time-consuming manufacturing process.

Furthermore, in order to improve the above-mentioned drawbacks, an insoluble dispersion resin of a copolymer of a monomer to be insolubilized and a monomer containing a long-chain alkyl moiety or a monomer containing two or more kinds of polar components has been developed. A method of improving the dispersibility, redispersibility, and storage stability of particles by forming them into particles is disclosed in JP-A-60-179751,
It is disclosed in No. 62-151868 and the like.

(Problem to be Solved by the Invention) On the other hand, in recent years, a method of printing 500 or more sheets using a master plate for offset printing using an electrophotographic method has been attempted, and improvements in the master plate in particular have been progressing. It has become possible to print more than 10,000 sheets in plate size. Further, the operating time of electrophotographic engraving systems has been shortened, and improvements have been made to speed up the development and fixing process.

JP-A-60-179751 and JP-A No. 62-15186
Dispersed resin particles produced according to the method disclosed in No. 8, when the development speed increases, the dispersibility of the particles,
The performance is still not necessarily satisfactory in terms of redispersibility, printing durability when the fixing time is shortened, or in the case of large-sized master plates (for example, A-3 size or larger). .

The present invention solves the problems of conventional liquid developers as described above.

An object of the present invention is to provide a liquid developer that can speed up the development and fixation process and has excellent dispersion stability, redispersibility, and fixation properties even in an electrophotolithography system using a large-sized master plate. That's true.

Another object of the present invention is to provide a liquid developer that enables the electrophotographic production of offset printing masters having excellent printing ink oil sensitivity and stiffness resistance.

Another object of the present invention is to provide a liquid developer suitable for various electrostatic photographs and various transfer applications in addition to the above-mentioned applications.

Still another object of the present invention is to provide a liquid developer that can be used in any system where a liquid developer can be used, such as inkjet recording, cathode ray tube recording, and recording of various change processes such as pressure changes or electrostatic changes. That's true.

(Means for Solving the Problems) An object of the present invention is to provide an electrostatic photographic liquid developer comprising at least a resin dispersed in a non-aqueous solvent having an electrical resistance of 10'Ωcm or more and a dielectric constant of 3.5 or less. In the above, the dispersed resin particles are soluble in the well water solvent but do not polymerize in the presence of a resin that does not contain a graph 1 group that is soluble in the nonaqueous solvent and polymerizes with the monomer. Carboxyl group, sulfo group, hydroxyl group, formyl group, At least one oligomer (B) having a number average molecular weight of I04 or less, which is formed by bonding at least one polar group selected from amino group, H or -OR' group (R- represents a hydrocarbon group) This was achieved by an electrostatic photographic liquid developer characterized by copolymer resin particles obtained by polymerizing a solution containing one type of developer.

General formula (+) HX-Y In formula (1), X is -COO--0CO--CIl, 0
CO-1R1at C1l, COO-1-0--3O*--CON--5O
J-1 or 1 to 18 hydrocarbon groups).

Y represents a hydrocarbon group having 1 to 22 carbon atoms.

at and a2 may be the same or different, and each represents a hydrogen atom, a halogen atom, a cyano group, a hydrocarbon group having 1 to 8 carbon atoms, -COO-R3, or a hydrocarbon group having 1 to 8 carbon atoms. -COO-R'(R' represents a hydrogen atom or a hydrocarbon group having 1 to 18 carbon atoms).

Hereinafter, the liquid developer of the present invention will be explained in detail.

The electrical resistance used in the present invention is 109 Ωcm or more, and the dielectric constant is 3.
Preferably, linear or branched aliphatic hydrocarbons, alicyclic hydrocarbons, or aromatic hydrocarbons, and halogen-substituted products thereof can be used as the carrier liquid. For example, octane, isooctane. , Decane, Isodecane, Decalin, Nonane, Dodecane, Isododecane, Isopar E1 Isopar G, Isopar H, Isopar L
(Isopar; Exxon product name), Sherzol 7
0, Shellsol 71 (Shellsol; trade name of Shell Oil Co.), Amsco OMS, Amsco 460 solvent (Amsco: trade name of Spiriff Co.), etc. are used alone or in combination.

Non-aqueous dispersed resin particles (hereinafter sometimes referred to as latex particles), which are the most important component in the present invention, are prepared by dispersing the monomer (A) and oligomer in a non-aqueous solvent in the presence of a dispersion stabilizing resin. (B) (so-called polymerization granulation method).

Here, as the non-aqueous solvent, basically any solvent can be used as long as it is miscible with the carrier liquid of the electrostatic photographic liquid developer.

That is, as a solvent used when manufacturing dispersed resin particles, the above-mentioned solvents are used. Preferred examples include linear or branched aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, and halogen-substituted products thereof, as long as they are miscible with body fluids. For example, hexane, octane, isooctane,
Decane, Isodecane, Decalin, Nonane, Dodecane, Isododecane, Isopar E1 Isopar G, Isopar H1 Isopar L1 Shersol 70. Sherzoll 7
1° Amsco OMS, Amsco 460 solvent, etc. are used alone or in combination.

Solvents that can be used in combination with these solvents include alcohols (e.g., methyl alcohol, ethyl alcohol, propyl alcohol, butyl alcohol, fluorinated alcohol, etc.), ketones (e.g., acetone, methyl ethyl ketone, cyclohexanone, etc.) , carboxylic acid esters (e.g. methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methyl propionate, ethyl propionate, etc.), ethers (e.g. diethyl ether, dipropyl ether, tetrahydrofuran, dioxane, etc.), halogenated hydrocarbons (eg, methylene dichloride, chloroform, carbon tetrachloride, dichloroethane, methyl chloroform, etc.).

It is preferable that the non-aqueous solvent used in the mixture be removed by heating or distillation under reduced pressure after polymerization and granulation, but even if it is brought into the liquid developer as a latex particle dispersion, it will not affect the liquid in the developer. There is no problem as long as the resistance is within a range that satisfies the condition of 10<9 >[Omega]C- or more.

Usually, it is preferable to use the same solvent as the carrier liquid at the stage of resin dispersion production, and as mentioned above, linear or branched aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, halogenated Examples include hydrocarbons.

The dispersion stabilizing resin necessary to make a stable resin dispersion of the solvent-insoluble polymer produced by polymerizing the monomer in a non-aqueous solvent does not contain a graft group that polymerizes with the monomer. As the resin, conventionally known dispersion stabilizing resins can be used. That is, various synthetic resins or natural resins soluble in non-aqueous media may be used alone or in combination of two or more.
For example, an alkyl chain or an alkenyl chain having a total of 6 to 32 carbon atoms [These aliphatic groups may contain substituents such as a halogen atom, a hydroxy group, an amino group, an alkoxy group, or an oxygen atom, a sulfur atom, esters of acrylic acid, methacrylic acid, or crotonic acid, having carbon atoms such as nitrogen atoms and carbon-carbon bonds in the main chain; , alkyl vinyl ethers, or olefins such as butadiene, isoprene, diisobutylene, etc., or a copolymer of a combination of two or more thereof, and furthermore, a polymer soluble in a non-aqueous solvent such as those mentioned above is formed. A copolymer obtained by polymerizing the monomer and one or more of the following various monomers at a ratio within a range that allows the resulting copolymer to be soluble in a non-aqueous solvent can also be used.

Examples of such monomers include vinyl acetate, allyl acetate, methyl, ethyl, or propyl esters of unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, and itaconic acid, and styrene derivatives (such as styrene , vinyltoluene, α-methylstyrene, etc.)
, acrylic acid, methacrylic acid, crotonic acid, maleic acid,
unsaturated carboxylic acids such as itaconic acid or their acid anhydrides;
Hydroxyethyl methacrylate, hydroxoethyl acrylate, diethylaminoethyl methacrylate, N
-vinylpyrrolidone, acrylamide, acrylonitrile, 2-chloroethyl methacrylate, 2.2.2-)
Hydroxy group, such as lyfluoroethyl methacrylate,
Examples include monomers containing various polar groups such as an amino group, an amine F group, a cyano group, a sulfonic acid group, a carbonyl group, a halogen atom, and a heterocycle.

Alternatively, in addition to the above synthetic resins, natural resins such as alkyd resins, alkyd resins modified with various fatty acids, linseed oil, and modified polyurethane resins can also be used.

The monomer (A) in the present invention may be any functional monomer that is soluble in non-aqueous solvents but becomes insolubilized by polymerization. I
Examples include monomers represented by I).

General formula (■) bl b" CH=C -Z In formula (II), T is -000-1-〇COCl1□0C
Represents O-1. Here, Zl is a hydrogen atom or a carbon number of 1 to 18
optionally substituted aliphatic groups (e.g., methyl group, ethyl group, propyl group, butyl group, 2-chloroethyl group, 2
-bromoethyl group, 2-cyanoethyl group, 2-hydroxyethyl group, hensyl group, chlorobenzyl group, methylhensyl group, methoxybenzyl group, phenethyl group, 3-phenylpropyl group, dimethylpencyl group, fluorobenzyl group, 2-methoxy ethyl group, 3-methoxypropyl group, etc.).

Z is a hydrogen atom or an optionally substituted aliphatic group having 1 to 6 carbon atoms (e.g., methyl group, ethyl group, propyl group, butyl group, 2-chloroethyl group, 22-dichloroethyl L
2,2.2-trifluoroethyl group, 2-bromoethyl group, 2-glycidylethyl group, 2-hydroxyethyl group,
2-hydroxypropyl group, 2.3-dihydroxypropyl group, 2-hydroxy-3-chloropropyl group, 2-anoethyl group, 3-cyanopropyl group, 2-nitroethyl group, 2-methoxyethyl group, 2-methanesulfonylethyl group , 2-ethoxyethyl group, N,N-dimethylaminoethyl group, N,N-diethylaminoethyl group, trimethoxysilylpropyl group, 3-bromopropyl group, 4-hydroxybutyl group, 2-furfurylethyl group, 2 -thienylethyl group, 2-pyridylethyl group, 2-morpholinoethyl group, 2-carboxyethyl group, 3-carboxypropyl group, 4-carboxybutyl group, 2-phosphoethyl group, 3-sulfopropyl group, 4-sulfobutyl group , 2-
carboxamidoethyl group, 3-sulfoamidopropyl group, 2-N-methylcarboquinamidoethyl group, cyclopentyl group, chlorocyclohexyl group, dichlorohexyl 7LF).

bl and b2 may be the same or different, and each represents the same content as aI or am in the general formula (1).

As a specific monomer (A), for example, a carbon number of 1 to 6
vinyl esters or allyl esters of aliphatic carboxylic acids (acetic acid, propionic acid, butyric acid, monochloroacetic acid, trifluoropropion fl), unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid, etc. optionally substituted alkyl esters or amides having 1 to 4 carbon atoms (alkyl groups such as methyl group, ethyl group, propyl group, butyl group, 2-chloroethyl i, 2-bromoethyl group, 2-fluoroethyl group,
Trifluoroethyl group, 2-hydroxyethyl group, 2-cyanethyl group, 2-nitroethyl group, 2-methquinethyl group, 2-methanesulfonylethyl group, 2-benzenesulfonylethyl group, 1-(N,N-dimethyl amino)ethyl group, 2(N,N-diethylamino)ethyl group, 2-
Carboquinoethyl group, 2-phosphoethyl group, 4-carboxybutyl group, 3-sulfopropyl group, 4-sulfobutyl group, 3-chloropropyl group, 2-hydroxo-3-chloropropyl group, 2-furfurylethyl group, 2-pyridinylethyl group, 2-thienylethyl group, trimethoxysilylpropyl group, 2-carboxyamidoethyl group, etc.), styrene derivatives (e.g. styrene, vinyltoluene, α
-Methylstyrene, vinylnaphthalene, chlorostyrene, dichlorostyrene, bromostyrene, vinylbenzenesulfonic acid, vinylbenzenesulfonic acid, chloromethylstyrene, hydroquinemethylstyrene, methoxymethylstyrene, N,N-dimethylaminomethylstyrene, vinyl- , benzenecarpoxyamide, vinylbenzenesulfonic acid F, etc.), unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, or cyclic anhydrides of maleic acid and itaconic acid, acrylonitrile, methacrylonitrile , a heterocyclic compound containing a polymerizable double bond group (specifically, for example, "Polymer Data Handbook - Group v! &i-J" edited by The Society of Polymer Science, p. 175-1
84, compounds described in Baifukan (published in 1986), such as N-vinylpyridine, N-vinylimidazole, N-
Vinylpyrrolidone, vinylthiophene, vinyltetrahydrofuran, vinyloxazoline, vinylthiazole,
N-vinylmorpholine, etc.).

Two or more types of monomers (A) may be used in combination.

Oligomer CB) is an oligomer with a number average molecular weight of 104 or less, which is formed by bonding the above-mentioned specific radial group only to one end of the main chain of a polymer consisting of repeating units represented by general formula (1). be.

In the general formula (+), the hydrocarbon groups contained in a'sa'', X and Y each have the indicated number of carbon atoms (as an unsubstituted hydrocarbon group), but these hydrocarbon groups are Good too.

In the formula (R2), in addition to a hydrogen atom, R2 in the substituent represented by X has 1 to 1 carbon atoms.
8 optionally substituted alkyl groups (e.g., methyl group,
Ethyl group, propyl group, butyl group, heptyl group, hequinyl group, octyl group, decyl group, dodecyl group, hexadecyl group, octadecyl group, 2-chloroethyl group, 2-bromoethyl group, 2-cyanoethyl group, 2-methoxycarbonylethyl group group, 2-methoxyethyl group, 3-bromopropyl group, etc.), optionally substituted alkenyl group having 4 to 18 carbon atoms (for example, 2-methyl-1-propenyl L2-
butenyl group, 2-pentenyl group, 3-methyl-2-pentenyl group, 1-pentenyl group, l-hexenyl group, 2-hexenyl group, 4-methyl-2-hexenyl group, etc.), carbon number 7 to 12 optionally substituted aralkyl groups (e.g., benzyl group, phenethyl group, 3-phenylpropyl group, naphthylmethyl group, 2-naphthylethyl group, chlorobenzyl group, bromohensyl group, methylbenzyl group, ethylbenzyl group, methoxybenzyl group) group, dimethylpencyl group, dimethoxybenzyl group, etc.), optionally substituted alicyclic groups having 5 to B carbon atoms (e.g., cyclohexyl group, 2-
cyclohexylethyl group, 2-cyclopentylethyl group, etc.), or an optionally substituted aromatic group having 6 to 12 carbon atoms (e.g. phenyl group, naphthyl group, tolyl group, xylyl group, propylphenyl group, butylphenyl group) group, octylphenyl group, dodecylphenyl group, methoxyphenyl group, ethoxyphenyl group, butoxyphenyl group, decyloxyphenyl group, chlorophenyl group, dichlorophenyl group, bromophenyl group, cyanophenyl group, acetylphenyl group, methoxycarbonylphenyl group, ethoxycarbonylphenyl group, butoxycarbonylphenyl group, acetamidophenyl group, propioamidophenyl group, dobcyroylamidophenyl group, etc.).

Substituents that may have a t^ group include halogen atoms (e.g. chlorine atom, bromine atom, etc.), alkyl groups (e.g. methyl group, ethyl group, propyl group, butyl group, chloromethyl group, methoxymethyl group) , etc.).

Y preferably represents a hydrocarbon group having 1 to 18 carbon atoms,
Specifically, it represents the same content as explained above.

al and R2 may be the same or different from each other,
Preferably a hydrogen atom, a halogen atom (for example, a chlorine atom, a bromine atom, etc.), a cyano group, an alkyl group having at to 3 carbon atoms (for example, a methyl group, an ethyl group, a propyl group, etc.), -
coo-R" or -C11,COO1?co (Rj represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms, an alkenyl group, an aralkyl group, an alicyclic group, or an aryl group, even if these are substituted. Specifically, it represents the same content as that described for R2 above.

It is more preferable that either al or R2 in formula (1) is a hydrogen atom.

Among the polar groups bonded only to one end of the polymer main chain having a number average molecular weight of 1X10' or less and containing at least one type of repeating unit represented by the above-mentioned T-shell type (RI), in the -P-R' group, Ro is a hydrocarbon group having 1 to 18 carbon atoms or -OR
'represents a group. The hydrocarbon group of RO is preferably an optionally substituted aliphatic group having 1 to 8 carbon atoms (e.g., methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, butenyl group, pentenyl group, hexenyl group). basis,
2-chloroethyl group, 2-cyanoethyl group, cyclopentyl group, cyclohexyl group, benzyl group, phenethyl group, chlorobenzyl group, bromohensyl group 71), or an optionally substituted aromatic group (e.g. phenyl group, tolyl group,
xylyl group, mesityl group, chlorophenyl group, bromophenyl group, methoxyphenyl group, cyanophenyl group, etc.)
represents.

When R11 represents an -OR' group, R1 preferably represents the same content as the hydrocarbon group of R6.

Moreover, among the polar groups of the present invention, the amino group is -NHt, a prime number 1
~1B hydrocarbon group, preferably having 1 to 8 carbon atoms
represents a hydrocarbon group, and specific C represents the same content as the hydrocarbon group of Ro described above.

Even more preferably Ro, R1, R4, R5 and R6
Examples of the hydrocarbon group include an optionally substituted alkyl group having 1 to 4 carbon atoms, an optionally substituted benzyl group, and an optionally substituted phenyl group.

Here, the polar group has a chemical structure in which it is directly bonded to one end of the polymer main chain or bonded via an arbitrary linking group. As the group connecting the formula (1) component and the polar group,
carbon-carbon bond (-double bond or double bond), carbon-
It is composed of any combination of atomic groups such as a heteroatom bond (heteroatoms include, for example, an oxygen atom, a sulfur atom, a nitrogen atom, a silicon atom, etc.) and a heteroatom-heteroatom bond.

Among the oligomers (B) of the present invention, preferred ones are of the formula (
IIla) or as shown by the formula (I[lb).

Formula (I[1a) a a” Q -W -4CIl -C)- Formula (I[1b) -(CI-C)-110-Y In formulas (Illa) and (llllb), a', a ” ,
X and Y represent the same contents as the symbols in formula (1).

Q represents the aforementioned polar group bonded to one end of formula (1).

W is a simple bond or -EC)-(R', R'' is water e. Methyl group, ethyl group, proSi-[R”, 1
110 each independently represents a single linking group selected from a hydrogen atom, a hydrocarbon group having the same content as 16 pt above, or a linking group composed of any combination thereof.

If the upper limit of the number average molecular weight of the oligomer CB) exceeds 1×10', the rigidity resistance will decrease. On the other hand, if the molecular weight is too small, stains tend to occur, so it is preferably lXl0'' or more.

The oligomer (B) of the present invention is a homopolymer component or a copolymer component selected from the repeating units represented by the general formula (1) or a monomer corresponding to the repeating unit represented by the general formula ([). It is composed of a copolymer component obtained by polymerizing the monomer and other monomers that can be copolymerized with the monomer. Examples of other monomers that become copolymer components together with the polymer component of formula (1) include acrylonitrile, methacrylonitrile, and heterocyclic compounds containing polymerizable double bond groups (specifically, monomers). (compounds similar to the heterocyclic compounds described for mer (A)), compounds containing a carboxamide group or sulfamide group and a polymerizable double bond group (for example, acrylamide, methacrylamide, diacetone acrylamide, 2-carboamide xoamidoethyl methacrylate, vinylhenzenecarpoxyamide, vinylbenzene sulfamide, 3-sulfoamidopropyl methacrylate-1, etc.)
etc.

The repeating unit represented by the above general formula (1) accounts for 30% by weight to 10% by weight in the oligomer (B) used in the present invention.
0% by weight is appropriate, preferably 50% to 100% by weight.
It is a heavy weight%.

In addition, the main chain of the polymer contains phosphono groups, carboxyl groups, sulfo groups, hydroxyl groups, formyl groups, amino groups, -P
A copolymerized acid containing a polar group of -R' group and containing no H content is preferred.

The dispersion stabilizing resin of the present invention, which has a specific polar group bonded only to one end of the polymer main chain, can be obtained by reacting various reagents with the ends of living polymers obtained by conventionally known anionic or cationic polymerization. (ionic polymerization method), radical polymerization method using a polymerization initiator and/or chain transfer agent containing a specific polar group in the molecule (radical polymerization method), or the above ionic polymerization method or It can be easily produced by a synthetic method such as a method in which a polymer containing a reactive group at the end obtained by a radical polymerization method is converted into the specific polar group of the present invention by a polymer reaction.

Specifically, P, 0reyfuss, R, P, Q
uirk.

Encycle, Po1yI11. Sci,εng,
, 7, 551 (1987), Yoshiki Nakajo, Yuya Yamashita [Dye and Pharmaceutical J, 30.232 (1985), Akira Ueda, Susumu Nagai [Science and Industry, 60.57 (198)
It can be produced by the method described in reviews such as 6) and the literature cited therein.

More specifically, the oligomer (B) of the present invention can be exemplified by the following compounds. However, the scope of the present invention is not limited to these.

(1) C1h snow 1100C (CIll)-t-5 (C1h-C)-0O
R n = integer from 1 to 10, C1(3 (8) CI!3110 (C
0 Shuttle 1s-(C1l.-C)-■ 0OR (4) CH.

1100C-(C1h)rcONII (CI+2)-
5(C11!-C)-0OR C1lYupal~4 integer+1O-CI+□ C11°C11°It(hS-C1hCIh-5(Clh-0-OOR 0OIl l1ff C)l, C00I+ (Cllz C)-C0NIIC11 0OR CIl, COO11 LH,ul, UI+ C11°C11°C11°<1h-C)-COOII 0OR CIl.

OOR The dispersion resin of the present invention comprises a monomer (A) and an oligomer (B
), and the important thing is that if the resin synthesized from these monomers is insoluble in the non-aqueous solvent, a desired dispersed resin can be obtained. More specifically, for the monomer (A) to be insolubilized, general formula (1)
It is preferable to use the oligomer (B) represented by 0.05 to 10% by weight, more preferably 0.1 to 5% by weight.

Even more preferably it is 0.3 to 3% by weight. Further, the molecular weight of the dispersion resin of the present invention is 103 to 106, preferably 104 to 5XlO'.

To produce the dispersion resin used in the present invention as described above, generally, the above-mentioned dispersion stabilizing resin, monomer (A), and oligomer (B) are mixed in a non-aqueous solvent with benzoyl peroxide, azo The polymerization may be carried out by heating in the presence of a polymerization initiator such as bisisobutyronitrile or butyllithium.
) A method of adding a polymerization initiator to a mixed solution of (2) a method of dropping monomer (A) and an oligomer (B) together with a polymerization initiator into a solution in which a dispersion stabilizing resin is dissolved; A method of optionally adding the remaining monomer mixture together with a polymerization initiator into a mixed solution containing the entire amount of the dispersion stabilizing resin and a part of the mixture of monomer (A) and oligomer (B); There is a method of optionally adding a mixed solution of a dispersion stabilizing resin, monomer (A), and oligomer (B) together with a polymerization initiator to a non-aqueous solvent, and any method can be used for production. Can be done.

The amount of monomer (A) and oligomer (B) is about 5 to 80 parts by weight, preferably 10 to 50 parts by weight, based on 100 parts by weight of the nonaqueous solvent.

The amount of the soluble resin which is the dispersion stabilizing resin is 1 to b parts, preferably 5 to 50 parts by weight, based on 100 parts by weight of the total monomers used above.

The amount of polymerization initiator is 0.1 to 5% (weight) of the total monomer amount
is appropriate.

Further, the polymerization temperature is about 50 to 180°C, preferably 60 to 120°C.The zero reaction time is preferably 1 to 15 hours.

When a polar solvent such as the above-mentioned alcohols, ketones, ethers, and esters is used in combination with the nonaqueous solvent used in the reaction, or when unreacted monomers (A) to be polymerized and granulated are If it remains, it is preferable to remove it by heating it to a temperature above the boiling point of the solvent or monomer or distilling it off under reduced pressure.

The non-aqueous dispersion resin produced according to the present invention as described above exists as fine particles with a uniform particle size distribution, and at the same time exhibits extremely stable dispersibility. The dispersibility is good even when the developing speed is increased, and redispersion is easy even when the developing speed is increased, and no stains are observed at all on various parts of the device.

Furthermore, when fixed by heating or the like, a strong film was formed and exhibited excellent fixing properties.

Furthermore, the liquid developer of the present invention speeds up the development and fixation process, and has excellent dispersion stability, redispersibility, and fixation properties even when a large-sized master plate is used.

Although the details of the reason why the redispersion and toner image fixing properties are significantly improved as described above when the resin particles of the present invention are used as a liquid developer are unknown, in the polymerization granulation method of the resin particles of the present invention, Even when oligomer (B) was added as a post-addition after polymerization granulation without using oligomer ([3)], the above effect was not observed. This is considered to be because the oligomer (B) used in the resin particles of the present invention modifies the surface of the resin particles.

In other words, since the positive group specified and bonded only to one end of the polymer main chain is polymerized and granulated in a non-aqueous solvent, it is bonded to the resin particle by an anchor effect, and the polymer main chain One of the main factors is presumed to be that the moiety modifies the surface of the resin particles and improves the affinity with the dispersion medium.

A coloring agent may be used in the liquid developer of the present invention if desired.

The colorant is not particularly limited; various conventionally known 1!71tj4 or dyes can be used.

When coloring the dispersion resin itself, for example, one method of coloring is to physically disperse it in the dispersion resin using pigments or dyes, and there are many known pigments or dyes. Examples of such materials include magnetic iron oxide powder, powdered lead iodide, carbon black, nigrosine, alkali blue, Hanzai Elo, quinacridone red, and phthalocyanine blue.

Another coloring method is disclosed in Japanese Patent Application Laid-open No. 57-4873.
There is a method of dyeing the dispersed resin with a preferred dye, as described in No. 8 and others. Alternatively, as another method, there is a method of chemically bonding a dispersion resin and a dye, as disclosed in JP-A No. 53-54029, or as described in JP-B No. 44-22955, etc. There is a method of producing a dye-containing copolymer by using a monomer containing a dye in advance during production by a polymerization granulation method.

Various additives may be added to the liquid developer of the present invention, as necessary, in order to strengthen charging characteristics or improve image characteristics. No., page 44, those specifically described are used.

For example, di-2-ethylhexyl sulfosuccinate metal salt,
Examples include naphthenic acid metal salts, higher fatty acid metal salts, lecithin, poly(vinylpyrrolidone), and copolymers containing half-maleic acid amide components.

The amounts of each main component of the liquid developer of the present invention are explained below.

The toner particles mainly composed of a resin and an optional colorant are used in an amount of 0.00 parts by weight based on 1000 parts by weight of the carrier liquid.
It is preferably 5 parts by weight to 50 parts by weight. If it is less than 0.5 parts by weight, image density will be insufficient, and if it exceeds 50 parts by weight, fogging will easily occur in non-image areas. Furthermore, the above-mentioned carrier for dispersion stabilization. A liquid soluble resin may also be used if necessary, and can be added in an amount of about 100 parts by weight to 100 parts by weight per 1000 parts by weight of the carrier liquid.

The charge control agent as described above is preferably used in an amount of 0.001 to 1.0 parts by weight per 1000 parts by weight of the carrier liquid.Additionally, various additives may be added as necessary, and the total amount of these additives is: The upper limit is regulated by the electrical resistance of the developer.

That is, if the electrical resistance of the liquid developer with toner particles removed becomes lower than 109 Ωcm, it becomes difficult to obtain a continuous tone image of good quality, so it is necessary to control the amount of each additive added within this limit. is necessary.

(Example) Examples of the present invention are illustrated below, but the content of the present invention is not limited thereto.

Oligomer °″-1 = 100 g of oligomer B-1 methyl methacrylate, 5 g of thioglycolic acid
A mixed solution of 150 g of toluene and 50 g of methanol was heated to 70° C. while stirring under a nitrogen stream.

2.2'-azobis(isobutyronitrile) (abbreviation A,
1. B, N,) was added at a pressure of 1.5 g and reacted for 4 hours.

Furthermore, A.1. 0.4 g of B and N were added and reacted for 4 hours.

After cooling, this reaction solution was reprecipitated into methanol/water ((4/l) volume ratio) mixed solution 21, the methanol solution was separated by decantation, the viscous substance was dried, and the colorless viscous substance was 75g was obtained.The number average molecular weight of the polymer was 2.800.
Met.

In Production Example 1, 5 g of thioglycolic acid,
Oligomers B-2 to B-12 were produced in the same manner as in Production Example 1, except that the mercapto compounds shown in Table 1 below were used. The number average molecular weight of the obtained oligomer was 2,50
It was 0 to 3,500.

Table 1 Table 2 Sesame's ″ 13-23N τ Sesame 8-13 Same as Production Example 1 except that the monomer in Table 2 was used instead of methyl methacrylate. Each oligomer B-13 to B-23 was manufactured by operating the following procedure.The number average molecular weight of the obtained oligomer was 2.500 to 3.500.

A mixture of 100 g of methyl methacrylate of O sesame I sesame B-24, 150 g of toluene, and 50 g of ethanol? The 8 liquid was heated to a temperature of 75°C while stirring under a nitrogen stream. 2. Add 8 g of 2'-Azobis (Cyanovaler M) (abbreviations A, C, V) and SEi
The mixture was reacted for 4 hours, and then 2 g of ^, C, and V were added and reacted for 4 hours. After cooling the obtained reaction solution, methanol/water ((4/
1) Volume ratio) After reprecipitation in a mixed aqueous solution and separating the methanol aqueous solution with decanethisilane, the viscous material was dried. Collection 1
At 70 g, the number average molecular weight of the polymer was 2,600.

Production Example 2 except that the azobis compounds shown in Table 3 below were used in place of "ζ" and polymerization initiators A, C, and V in Production Example 24.
Oligomers B-25 to B-33 were produced in the same manner as in 4. The number average molecular weight of the obtained oligomer was 2.0
It was 00-4,000.

Table-3 R-N=N-R: Azobis compound (continued) Latex 1 = Manufacture of Latex D-1 20 g of poly (octadecyl methacrylate), vinyl acetate + OOg, 1.0 g of oligomer B-1 and 380 g of Isoper H The mixed solution was heated to 70°C while stirring under a nitrogen stream.
The mixture was added and reacted for 6 hours. 20 minutes after the addition of the initiator, white turbidity occurred and the reaction temperature rose to 88°C. /! 1 degree is 1
The temperature was raised to 00'C, and the mixture was stirred for 2 hours to distill off unreacted vinyl acetate. After cooling, pass through 200 mesh nylon cloth.
The obtained white dispersion had a polymerization rate of 88% and an average particle size of 0.2.
It was 4zu latex.

It was a prisoner's range.

Table 4 In production example 1 of Latinx particles, oligomer B-1
A white dispersion was obtained in the same manner as in Production Example 1, except that the oligomer shown in Table 4 below was used instead. The polymerization rate of each white dispersion was 85 to 9 leaves. In addition, the average particle diameter of each latex was 0.23 to 0.27.
A white dispersion was obtained in the same manner as in Production Example 1, except that each dispersion stabilizing resin and oligomer listed in Table 5 below was used instead of Example 1. The polymerization rate of the obtained dispersion was 85-90
%Met.

- 1x & 35x D - Reacted for 362 hours. After cooling, 200 g of nylon poly(octadecyl methacrylate), vinyl acetate too
g, 5 g of crotonic acid 1.0 g of oligomer B-3
A mixed solution of 468 g of Isopar E and Isopar E was heated to 70° C. while stirring under a nitrogen stream. ^, B, V, N
After 6 hours of reaction, the temperature was raised to 100°C and the mixture was stirred for 1 hour to distill off the remaining vinyl acetate. After cooling, the resulting white dispersion was passed through a 200-mesh nylon cloth, with a polymerization rate of 85% and an average particle size of 0.2.
It was 3- latex.

The resulting white dispersion was passed through a cloth with an average particle size of 0.24-
It was made of latex.

A mixed solution of 85 g of vinyl acetate, 15 g of N-vinylpyrrolidone, 1.2 g of oligo 7-B-9, and 380 g of n-decane was heated to a temperature of 75° C. with stirring under a nitrogen stream. 7g of A, 1B, and N were added and reacted for 4 hours, and then A, 1. 0.5 g of n, l+ was added and reacted for 2 hours.

After cooling, the resulting white dispersion was passed through a 200-mesh nylon cloth, and the resulting white dispersion was latex with an average particle size of 0.20.

Poly (dodecyl methacrylate) 20g, vinyl acetate long, 4-pentenoic acid 6.0g, oligomer B-1
Mixture of 0.8 g of 5 and 380 g of Isopar G l6
The liquid was heated to a temperature of 70°C while stirring under a nitrogen stream. Add 0.7g of hendyl peroxide and react for 4 hours.
Furthermore, 0.5 g of hendyl peroxide was added, and a mixed solution of 20 g of poly(octadecyl methacrylate), methyl methacrylate long, 1.0 g of oligomer B-19, and 470 g of n-decane was heated at 70°C with stirring under a nitrogen stream. It was heated to

^, 1. B, N, 1. Og was added and reacted for 2 hours.

A few minutes after adding the initiator, a cloudy blue color started and the reaction temperature was 90°C.
It rose to After cooling, coarse particles were removed through a 200-mesh nylon cloth, and the resulting white dispersion was latex with an average particle size of 0.45.

In Production Example 1 of 14OA Latex Particles, the same procedure as Production Example 1 was carried out except that oligomer B-1 was removed. The obtained white dispersion was a latex with a polymerization rate of 85% and an average particle size of 0.25 m.

In production example 1 of 41 B latex particles, 18 g of poly(octadecyl methacrylate-N, 100 g of vinyl acetate, 1.0 g of octadecyl methacrylate, and 385 g of Isopar 11)
Mixing of g/8. The operation was carried out in the same manner as in Production Example 1 except that & was used.

The obtained white dispersion had a polymerization rate of 85% and an average particle size of 0.22.
% latex.

In production example 1 of 42C latex particles, 18 g of poly(octadecyl methacrylate), 100 g of vinyl acetate, 1 g of a monomer (+) having the following chemical structure, and 3 g of Isopar H were added.
85g of mixture? The operation was carried out in the same manner as in Production Example 1 except that 8Wi was used.

The obtained white dispersion had a polymerization rate of 86% and an average particle size of 0.24.
It was latex that caught my eye.

Monomer (+) CH.

Example 1 10 g of dodecyl methacrylate/acrylic acid copolymer [copolymerization ratio (9515) weight ratio], 10 g of nigrosine, and 30 g of Shell Silua 1 were placed in a paint shaker (Tokyo't # machine @ 3) with glass beads and stirred for 4 hours. A fine dispersion of nigrosine was obtained.

30g of latex D-1 of latex particle production example 1
A liquid developer for electrostatic photography was prepared by diluting 2.5 g of the above nigrosine dispersion and 0.08 g of the octadecene-half-maleic acid octadesolamide copolymer to 12 parts of 71 parts of sol.

(Comparative Developer A-C) In the manufacturing example of the liquid developer described above, latex D-1 was replaced with the following latex, and comparative liquid developers A, B,
Three types of C were produced.

Comparative liquid developer A Latex of Nilatex particle production example 40 Comparative liquid developer B Latex of Nilatex particle production example 41 Comparative liquid developer C; Latex of latex particle production example 42 These liquid developers Using this as a developer in a fully automatic plate making machine ELP404ν (manufactured by X-Shi Photo Film), an electrophotographic light-sensitive material ELP Master ■ type (manufactured by Fuji Photo Film@J) was exposed and developed.

The plate making speed was 5 plates/min. Furthermore, after processing 2,000 sheets of the ELP master ■ type, the presence or absence of toner adhesion stains on the developing device was observed. Darkening rate of copied image (
(image area) was performed using 20% of the manuscript. The results are shown in Table-6.

Table 6 When each developer was plate-made under the above-mentioned plate-making conditions, the developer of the present invention was the only one that did not stain the developing device and provided a clear image on the 2000th plate-making plate.

On the other hand, off-cent printing master plates (ELP masters) obtained by plate making using each developer were printed using a conventional method, and the number of prints was compared until the printed image showed missing characters, fading in solid areas, etc. However, in the master plates obtained using the developers of the present invention, Comparative Example A, and Comparative Example C, the problem did not occur even after 10,000 sheets or more, but in the mask plate using Comparative Example B, the problem occurred after 8,000 sheets.

As shown in the above results, only the developer made from the resin particles of the present invention caused no staining of the developing device and at the same time significantly increased the number of master plates printed.

That is, in the case of Comparative Example A, there was no problem with the number of prints, but the developing device was extremely dirty and could not withstand continuous use.

In addition, in the case of Comparative Example B and Comparative Example C, the plate making speed was 5.
When used at a fast plate-making speed of 2 to 3 sheets/min (conventionally, plate making speed of 2 to 3 sheets/min), the developing device (especially the rear ring #If
After 2,000 copies, the image quality of the copied images on the plate is affected (D ff1ax).
(deterioration of color, fading of thin lines, etc.) started to appear. The number of master plates printed was not a problem in Comparative Example C, but decreased in Comparative Example B.

These results demonstrate that the resin particles of the present invention are clearly superior.

Example 2 White dispersion too obtained in latex particle production example 2
A mixture of 1.5 g of Sumikalon Plaque and 1.5 g of Sumikalon Plaque was heated to 100°C and stirred for 4 hours. After cooling to room temperature, the remaining dye was removed by passing it through a 200-mesh nylon cloth to obtain a black resin dispersion with an average particle size of o and 20.

32g of the above black resin dispersion, 0 zirconium naphthenate
．． A liquid developer was prepared by diluting 15 g of a higher alcohol FOC-1400 (manufactured by Nissan Chemical Company) with Shell Silua 1 le.

When this was developed using the same apparatus as in Example I, it was found that 200
Even after developing 0 sheets, no toner adhesion stains occurred on the device.

Furthermore, the image quality of the obtained master plate for offset/two-print printing was clear, and the image quality of the printed matter after printing 10,000 sheets was also extremely clear.

Example 3 White dispersion 10 obtained in latex particle production example 36
A mixture of 0 g and 3 g of Biku [・Ria Blue B] was heated to a temperature of 7.
The mixture was heated to 0°C to 80°C and stirred for 6 hours. After cooling to room temperature, the remaining dye was removed by passing it through a 200 mensier nylon cloth to obtain a blue resin dispersion with an average particle size of 0.16.

32g of the above blue resin dispersion, 0 zirconium naphthenate
．． A liquid developer was prepared by diluting 15 g of higher alcohol FOC-1600 (manufactured by Nichikagaku Kagaku) to 11 of Isopar 14.

When this was developed using the same device as in Example 1, 20
Even after developing 00 sheets, no toner adhesion stains were observed on the device. Moreover, the image quality of the obtained master plate for offset printing was clear, and the image quality of the printed matter after single-sheet printing was also very clear.

Example 4 32 g of white resin dispersion obtained in latex particle production example 3
, semi-docosanylamidation of 2.5 g of the nigrosone dispersion obtained in Example 1 and the copolymer of diisobutylene and maleic anhydride'j:! IJ0.02 g to Isopar G 12
A liquid developer was prepared by diluting it to .

This was developed using the same device as in Example].
Even after developing 0 sheets, no toner adhesion stains were observed on the device. Furthermore, the image quality of the obtained master plate for offset printing and the image quality of the printed matter after single-sheet printing were both very clear.

Furthermore, after leaving this developer for 3 months, the same treatment as above was carried out, but there was no difference at all from before aging.

Example 5 Poly (denel methacrylate) 10g, Isopar H
30 g and 8 g of alkali blue were placed in a paint Sony car together with glass beads and dispersed for 2 hours to obtain a fine dispersion of alkali blue.

30 g of the white resin dispersion D-13 obtained in Production Example 13 of Latex Particles, and the above alkali blue dispersion Pa4.
A liquid developer was prepared by diluting 2 g of a copolymer of octadecyl vinyl ether and maleic anhydride, 0.06 g of a semi-docosanylamidate, and 15 g of higher alcohol FOC-1400 into Isopar G IP.

When this was developed using the same device as in Example 1, the result was 200
Even after developing 0 sheets, no toner adhesion to the device was observed. In addition, both the image quality of the obtained master plate for offset printing and the image quality of 11 prints after single printing were very clear.

Examples 6 to 26 Each liquid developer was produced in the same manner as in Example 5, except that resin particles shown in Table 7 below were used instead of resin particles D-13.

Table 7 When this was developed using the same device as in Example 1, 200
Even after developing 0 sheets, little or no toner adhesion to the device was observed.

In addition, both the image quality of the obtained master plate for offset printing and the image quality of the printed matter after single-sheet printing were very clear.

(Effects of the Invention) According to the present invention, a developer with excellent dispersion stability, redispersibility, and fixing properties was obtained. In particular, even when used under plate-making conditions with extremely high plate-making speeds, no lag occurs in the developing device, and both the image quality of the obtained offset printing master plate and the image quality of printed matter after printing 10,000 sheets are extremely clear. there were.

Claims (1)

[Scope of Claims] An electrostatic photographic liquid developer comprising at least a resin dispersed in a non-aqueous solvent having an electrical resistance of 10^9 Ωcm or more and a dielectric constant of 3.5 or less, wherein the dispersed resin particles A monofunctional monomer (A) that is soluble in the nonaqueous solvent but becomes insolubilized by polymerization in the presence of a resin that is soluble in an aqueous solvent and does not contain a graft group that polymerizes with the monomer. and the following general formula (I)
A carboxyl group, a sulfo group, a hydroxyl group,
There are formyl groups, amino groups, phosphono groups, and ▲mathematical formulas, chemical formulas, tables, etc.▼ groups [R^0 is a hydrocarbon group or -
OR^1 group (R^1 represents a hydrocarbon group)] At least one type of oligomer (B) having a number average molecular weight of 10^4 or less, which is formed by bonding at least one type of polar group selected from 1. A liquid developer for electrostatic photography, characterized in that it is a copolymer resin particle obtained by polymerizing a solution containing the developer. General formula (I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ In formula (I), X is -COO-, -OCO-, -CH
_2OCO-, -CH_2COO-, -O-, -SO_
Represents 2-, -CON-, -SO_2N-, or ▲There are mathematical formulas, chemical formulas, tables, etc.▼. (R^2 represents a hydrogen atom or a hydrocarbon group having 1 to 18 carbon atoms). Y represents a hydrocarbon group having 1 to 22 carbon atoms. a^1 and a^2 may be the same or different from each other,
Each hydrogen atom, halogen atom, cyano group, carbon number 1-8
-COO-R^3 or -COO-R^3 via a hydrocarbon group having 1 to 8 carbon atoms (R^3 represents a hydrogen atom or a hydrocarbon group having 1 to 18 carbon atoms) represents.