JP2003149875A - Liquid developer for electrostatic photography - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid developer excellent in charge stability, dispersion stability, re-dispersing property and fixing property of particles and capable of exhibiting excellent sensitivity for printing ink and printing durability even in an electrophotographic plate making system including a fast developing-fixing process and using a large-size master plate. SOLUTION: The liquid developer for electrostatic photography is prepared by dispersing at least resin particles in a nonwater solvent having >=10<9> Ωcm resistivity and <=3.5 dielectric constant. The resin particles are copolymer resin particles obtained by polymerization and granulation in the presence of a monomer (A) which is soluble in a nonwater solvent and changes into insoluble by polymerization, a monofunctional monomer (B) having an amino group, a monofunctional monomer (C) having an acidic group selected from -PO3 H2 group, -SO3 H group and -SO2 H group, a monofunctional monomer (D) having a substituent containing a fluorine atom and/or a silicon atom, and a resin (P) for stabilization of dispersion containing a specified polymer component and dispersed in a colloidal state in the nonwater solvent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid developer for electrophotography, and particularly to dispersibility, storability, stability,
The present invention relates to a liquid developer for electrostatic photography, which has excellent redispersibility, image reproducibility, and fixability.

[0002]

2. Description of the Related Art A general liquid developer for electrostatic photography is an organic or inorganic pigment or dye such as carbon black, nigrosine or phthalocyanine blue, and a natural or synthetic resin such as alkyd resin, acrylic resin, rosin or synthetic rubber. Dispersed in liquids with high insulation and low dielectric constant such as aliphatic hydrocarbons, metal soap, lecithin, linseed oil,
A charge control agent such as a polymer containing a higher fatty acid or vinylpyrrolidone is added. In such a developer, the resin has a diameter of several nm as insoluble latex particles.
Although dispersed in the form of particles of several hundreds of nm, in the conventional liquid developer, the soluble dispersion stabilizing resin and the charge adjusting agent and the insoluble latex particles are insufficiently bonded to each other, so that the soluble dispersion stabilizing resin and the charge adjusting agent are The agent was in a state of being easily diffused in the solution. Therefore, there is a drawback that the soluble dispersion stabilizing resin is desorbed from the insoluble latex particles due to long-term storage and repeated use, and the particles settle, aggregate, and accumulate, or the polarity becomes unclear. Further, since particles once aggregated and accumulated are difficult to redisperse, the particles remain attached to various parts of the developing machine, leading to the failure of the developing machine such as dirt on the image area and clogging of the liquid feeding pump. In order to improve such problems, insoluble dispersed resin particles made of a copolymer of an insolubilizing monomer and a monomer containing a long-chain alkyl moiety or a monomer containing two or more polar components are used. A method for improving the dispersibility, storage stability and redispersibility of particles by using them is disclosed in JP-A-60-179751 and JP-A-62-151.
No. 868, etc. In addition, an insoluble dispersion resin composed of a copolymer of a monomer that becomes insoluble and a monomer that contains a long-chain alkyl moiety in the presence of a polymer that uses a bifunctional monomer or a polymer that uses a macromolecular reaction A method for improving the dispersibility, storage stability and redispersibility of particles by using particles is disclosed in JP-A Nos. 62-166362 and 63-66567. Furthermore, as a dispersion stabilizing resin, storage stability and redispersion are achieved by using a block copolymer composed of a solvating polymer part and a non-solvating polymer part, instead of a conventional random copolymer. To improve the properties is disclosed in JP-A-3-12666 and 3-7.
No. 7965, No. 3-225353, No. 4-46354
No., etc.

[0003]

On the other hand, in recent years, a method of printing a large number of 5000 or more sheets by using a master plate for offset printing by an electrophotographic system has been attempted. It has become possible to print more than 10,000 sheets in plate size. or,
The operation time of the electrophotographic plate making system has been shortened, and the development-fixing process has been accelerated. JP-A-60-179751, JP-A-62-151868, JP-A-62-166362, JP-A-63-66567, JP-A-3-12666, JP-A-3-77965, and JP-A-3-225.
No. 353 and No. 4-46354, the dispersed resin particles produced according to the means disclosed herein are those in the case where the developing speed is increased, the dispersibility and redispersibility of the particles are increased, and the fixing time is shortened. Alternatively, a large plate size (for example, A-
In the case of using a master plate of 3 sizes or more), the performance was not always satisfactory in terms of printing durability.

The present invention solves the above problems of the conventional liquid developer. Therefore, an object of the present invention is to provide excellent charge stability, dispersion stability, redispersibility, and fixability of particles even in an electrophotographic plate making system in which a development-fixing process is accelerated and a large plate size master plate is used. Another object is to provide a liquid developer. Another object of the present invention is to provide a liquid developer which enables the production of an offset printing plate having excellent printing ink oil sensitivity and printing durability by electrophotography. Another object of the present invention is to provide a liquid developer suitable for various ordinary electrophotography.

[0005]

It has been found that the above object can be achieved by the following constitution. (1) In a liquid developer for electrostatic photography, wherein at least resin particles are dispersed in a non-aqueous solvent having an electric resistance of 10 ⁹ Ωcm or more and a dielectric constant of 3.5 or less, the dispersed resin particles are Monomer (A) containing at least one monofunctional monomer (A) which is soluble in an aqueous solvent and becomes insoluble by polymerization, which contains an amino group represented by the general formula (I)
Monomer containing at least one monofunctional monomer (B) copolymerizable with B, at least one acidic group selected from a —PO ₃ H ₂ group, a —SO ₃ H group and a —SO ₂ H group. Monofunctional Copolymerizable with Monomer (A) Having at least One Monofunctional Monomer (C) Copolymerizable with Body (A), Fluorine Atom and / or Silicon Atom-Containing Substituent Presence of at least one dispersion stabilizing resin (P) which is at least one of the monomer (D) and at least a polymerization component represented by the following general formula (PI) and is colloidally dispersed in the non-aqueous solvent. Below is a liquid developer for electrostatic photography, characterized in that it is a copolymer resin particle obtained by polymerization granulation.

[0006]

[Chemical 4]

In the general formula (I), R ¹ and R ² may be the same or different and each represents a hydrogen atom or a hydrocarbon group having 1 to 22 carbon atoms, or R ¹ and R ² are combined to form a nitrogen atom. You may form a ring with an atom.

[0008]

[Chemical 5] In general formula (PI), V ⁰ is -COO-, -OCO-,-.
_{(CH 2) r COO -,} - (CH 2) r OCO -, - O- or

[Chemical 6] (Where X is a direct bond, -O-, -OCO- or -CO
Represents O-). r represents an integer of 1 to 12. L
Is an alkyl group having 8 to 32 carbon atoms or 8 to 32 carbon atoms
Represents an alkenyl group. b ¹ and b ² may be the same as or different from each other and each represents a hydrogen atom, a halogen atom, a cyano group, a hydrocarbon group, —COO-D ¹ , or —COO-D ¹ via a hydrocarbon group ( Here, D ¹ represents a hydrogen atom or an optionally substituted hydrocarbon group).

(2) The dispersion stabilizing resin (P) comprises a block containing at least a polymerization component represented by the general formula (PI) and a block not containing the polymerization component represented by the general formula (PI). A liquid developer for electrostatic photography according to (1) above, which is a block copolymer.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The liquid developer for electrostatic photography of the present invention will be described below. The non-aqueous solvent having an electric resistance of 10 ⁹ Ω · cm or more and a dielectric constant of 3.5 or less used in the liquid developer for electrostatic photography of the present invention is preferably a linear or branched aliphatic hydrocarbon or alicyclic ring. Formula hydrocarbons, aromatic hydrocarbons, halogen-substituted products of these hydrocarbons, silicone liquids, silicone solvents such as silicone oil, and the like can be mentioned.

For example, hydrocarbon solvents include pentane, isoheptane, octane, isooctane, decane,
Isodecane, decalin, nonane, dodecane, isododecane, cyclohexane, cyclooctane, cyclodecane,
Benzene, toluene, xylene, mesitylene, Isopar E, Isopar G, Isopar H, Isopar L (Isopar; trade name of Exxon Corporation), Shersol 70,
Shelsol 71 (Shellsol; trade name of Shell Oil Co.), Amsco OMS, Amsco 460 solvent (Amsco; trade name of Spirits Co., Ltd.) and the like.

There is a fluorocarbon solvent as the halogen-substituted hydrocarbon solvent, and for example, perfluoroalkanes represented by C _n F _{2n + 2} such as C ₇ F ₁₆ and C ₈ F ₁₈ (“Fluorinate manufactured by Sumitomo 3M Ltd.”). PF5080 "," Florinert PF5070 "(trade name), etc., fluorine-based inert liquid (" Fluorinert FC series "(trade name) manufactured by Sumitomo 3M, etc.), fluorocarbons (" Krightox GPL series "manufactured by DuPont Japan Limited) (Brand name), CFCs (“HCF manufactured by Daikin Industries, Ltd.”
C-141b "(trade name), _{etc.), F (CF 2) 4} CH 2 CH
₂ I, F (CF ₂ ) ₆ I, etc. iodinated fluorocarbons (“I-142 manufactured by Daikin Fine Chemical Laboratories”
0 "," I-1600 "(trade name), etc.

Examples of silicone solvents for silicone liquids and silicone oils include dialkyl polysiloxanes (eg, hexamethyldisiloxane, tetramethyldisiloxane, octamethyltrisiloxane, hexamethyltrisiloxane, heptamethyltrisiloxane, decamethyltetrasiloxane, Trifluoropropylheptamethyltrisiloxane, diethyltetramethyldisiloxane, etc.), cyclic dialkylpolysiloxane (eg, hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane,
Tetra (trifluoropropyl) tetramethylcyclotetrasiloxane, etc.), methylphenyl silicone oil (eg, KF56, KF58 (trade name of Shin-Etsu Silicon Co., Ltd.), etc.) and the like.

In the present invention, these solvents are used alone or as a mixture. The upper limit of the electric resistance of such a non-aqueous solvent is preferably about 10 ¹⁶ Ωcm, and the lower limit of the dielectric constant is preferably about 1.80.

The non-aqueous dispersion resin particles (hereinafter sometimes referred to as "resin particles" or "latex particles"), which is the most important constituent part of the liquid developer of the present invention, is a specific component in the non-aqueous solvent. In the presence of the dispersion-stabilizing resin (P) containing (formula (PI)), at least one kind of monofunctional monomer (A), a monofunctional group containing an amino group represented by the general formula (II) A monofunctional monomer (C) containing at least one acidic group selected from at least one of the monomer (B), a —PO ₃ H ₂ group, a —SO ₃ H group and a —SO ₂ H group. At least one, and fluorine atom and /
Alternatively, the monofunctional monomer (D) having a silicon atom-containing substituent is polymerized and granulated.

Here, as the non-aqueous solvent, basically,
Any material that is miscible with the non-aqueous solvent of the liquid developer can be used.

That is, the solvent used for producing the dispersed resin particles is preferably linear or branched aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons and halogen-substituted products thereof. To be For example, octane, isooctane, decane, isodecane, decalin, nonane, dodecane, isododecane, isoper E,
Isopar G, Isopar H, Isopar L, Shelsol 70, Shelsol 71, Amsco OMS, Amsco 460 solvent and the like are used alone or in combination.

Organic solvents that can be used in combination with these non-aqueous solvents include alcohols (eg, ethyl alcohol, propyl alcohol, butyl alcohol,
Ethylene glycol monomethyl ether, fluoroalcohol, etc.), ketones (eg, methyl ethyl ketone, acetophenone, cyclohexanone, etc.), carboxylic acid esters (eg, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methyl propionate, ethyl propionate) , Ethylene glycol monomethyl ether acetate etc.), ethers (eg dipropyl ether, ethylene glycol dimethyl ether, tetrahydrofuran, dioxane etc.), halogenated hydrocarbons (eg
Chloroform, dichloroethane, methyl chloroform, etc.) and the like.

It is desirable that these organic solvents to be mixed and used are distilled off under heating or under reduced pressure after polymerization and granulation. There is no problem as long as the condition that the resistance is 10 ⁹ Ωcm or more and the dielectric constant is 3.5 or less is satisfied.

Usually, it is preferable to use the same solvent as the non-aqueous solvent of the liquid developer in the step of producing the resin particle dispersion,
As described above, linear or branched aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, halogenated hydrocarbons and the like can be mentioned.

The monofunctional monomer (A) in the present invention is
Any monofunctional monomer that is soluble in the non-aqueous solvent but is insolubilized by polymerization may be used. Specific examples include monomers represented by the following general formula (II).

[0022]

[Chemical 7]

In the general formula (II), V ¹ is --COO-- or --O.
_{CO -, - CH 2 OCO -} , - CH 2 COO -, - O-,
-CONHCOO-, -CONHOCO-, -SO
^{_{2 -, - CON (Q 1}} ) -, - SO 2 N (Q 1) -., Or a phenylene group (hereinafter sometimes to be referred to as a phenylene group and "-Ph-" Incidentally, phenylene group 1,2 -, 1,
Includes 3- and 1,4-phenylene groups. ) Represents. Here, Q ¹ is a hydrogen atom or an optionally substituted aliphatic group having 1 to 8 carbon atoms (eg, methyl group, ethyl group, propyl group, butyl group, 2-chloroethyl group, 2
-Bromoethyl group, 2-cyanoethyl group, 2-hydroxyethyl group, benzyl group, chlorobenzyl group, methylbenzyl group, methoxybenzyl group, phenethyl group, 3-phenylpropyl group, dimethylbenzyl group, fluorobenzyl group, 2-methoxy Ethyl group, 3-methoxypropyl group and the like).

T is a hydrogen atom or an optionally substituted aliphatic group having 1 to 6 carbon atoms (eg, methyl group, ethyl group, propyl group, butyl group, 2-chloroethyl group, 2,2-dichloroethyl group, 2-bromoethyl group, 2-hydroxyethyl group, 2-hydroxypropyl group, 2,3-dihydroxypropyl group, 2-hydroxy-3-chloropropyl group, 2-cyanoethyl group, 3-cyanopropyl group, 2
-Nitroethyl group, 2-methoxyethyl group, 2-methanesulfonylethyl group, 2-ethoxyethyl group, 3-bromopropyl group, 4-hydroxybutyl group, 2-furfurylethyl group, 2-thienylethyl group, 2- Carboxyethyl group, 3-carboxypropyl group, 4-carboxybutyl group, 2-carboxyamidoethyl group, 2-N-methylcarboxyamidoethyl group, cyclopentyl group, chlorocyclohexyl group, dichlorohexyl group, etc.).

B ¹ and b ² may be the same as or different from each other, and preferably a hydrogen atom or a halogen atom (for example,
Chlorine atom, bromine atom, etc.), cyano group, alkyl group having 1 to 3 carbon atoms (eg, methyl group, ethyl group, propyl group, etc.), —COO-Q ² or —CH ₂ —COO-Q ² [wherein Q ² is a hydrogen atom or optionally substituted carbon atom 1
It represents a hydrocarbon group of 0 or less (for example, an alkyl group, an alkenyl group, an aralkyl group, an aryl group, or the like).

As a specific monofunctional monomer (A),
For example, vinyl esters or allyl esters of aliphatic carboxylic acids having 1 to 6 carbon atoms (acetic acid, propionic acid, butyric acid, monochloroacetic acid, etc.); Unsaturation of acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid, etc. Alkyl esters or amides of carboxylic acid having 1 to 4 carbon atoms which may be substituted (for example, methyl group, ethyl group, propyl group, butyl group, 2-chloroethyl group, 2-bromoethyl group, 2-hydroxy group as alkyl group) Ethyl group, 2-cyanoethyl group, 2-nitroethyl group, 2-methoxyethyl group, 2-methanesulfonylethyl group, 2-
Benzenesulfonylethyl group, 2-carboxyethyl group, 4-carboxybutyl group, 3-chloropropyl group,
2-hydroxy-3-chloropropyl group, 2-furfurylethyl group, 2-thienylethyl group, 2-carboxamidoethyl group, etc.);

Styrene derivatives (for example, styrene, vinyltoluene, α-methylstyrene, vinylnaphthalene,
Chlorostyrene, dichlorostyrene, bromostyrene,
Vinylbenzenecarboxylic acid, chloromethylstyrene, hydroxymethylstyrene, methoxymethylstyrene, vinylbenzenecarboxamide, vinylbenzenesulfoamide, etc.); acrylic acid, methacrylic acid, crotonic acid,
Unsaturated carboxylic acids such as maleic acid and itaconic acid; cyclic acid anhydrides of maleic acid and itaconic acid; acrylonitrile;
Methacrylonitrile; a heterocyclic compound containing a polymerizable double bond group (specifically, for example, described in "Polymer Data Handbook-Basic Edition", edited by The Polymer Society of Japan, p175-184, Baifukan (1986). Compounds such as N-vinylpyridine, N-vinylimidazole, N-vinylpyrrolidone, vinylthiophene, vinyltetrahydrofuran, vinyloxazoline, vinylthiazole and N-vinylmorpholine). The monomer (A) may be used in combination of two or more kinds.

Next, the monofunctional monomer (B) containing an amino group represented by the above general formula (I), which is copolymerizable with the monomer (A) used in the present invention, will be explained. In the monofunctional monomer (B), the polymerizable double bond group and the amino group are not directly bonded.

In the formula (I), R ¹ and R ² may be the same or different and are preferably a hydrogen atom or a carbon number of 1 to 22.
Optionally substituted alkyl group (for example, methyl group, ethyl group, propyl group, butyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, dodecyl group, tridecyl group, tetradecyl group, hexadecyl group, Octadecyl group, eicosyl group, docosyl group, 2-chloroethyl group, 2-bromoethyl group, 2-cyanoethyl group, 2-
Methoxycarbonylethyl group, 2-methoxyethyl group,
3-bromopropyl group, etc.), an alkenyl group having 4 to 18 carbon atoms and which may be substituted (for example, 2-methyl-1-propenyl group, 2-butenyl group, 2-pentenyl group, 3-methyl-2-pentenyl group). Group, 1-pentenyl group, 1-hexenyl group, 2-hexenyl group, 4-methyl-2-hexenyl group, decenyl group, dodecenyl group, tridecenyl group,
Hexadecenyl group, octadecenyl group, linolenyl group, etc.),

Aralkyl group having 7 to 12 carbon atoms which may be substituted (eg, benzyl group, phenethyl group, 3-phenylpropyl group, naphthylmethyl group, 2-naphthylethyl group, chlorobenzyl group, bromobenzyl group, methyl group). Benzyl group, ethylbenzyl group, methoxybenzyl group, dimethylbenzyl group, dimethoxybenzyl group, etc.), alicyclic group having 5 to 8 carbon atoms which may be substituted (for example, cyclohexyl group, 2-cyclohexylethyl group, 2- Cyclopentylethyl group) or an optionally substituted aromatic group having 6 to 12 carbon atoms (eg, phenyl group, naphthyl group, tolyl group, xylyl group, propylphenyl group, butylphenyl group, octylphenyl group, dodecylphenyl group) , Methoxyphenyl group, ethoxyphenyl group, butoxyphenyl group, decyl Shifeniru group, chlorophenyl group,
(Dichlorophenyl group, bromophenyl group, cyanophenyl group, acetylphenyl group, methoxycarbonylphenyl group, ethoxycarbonylphenyl group, butoxycarbonylphenyl group, acetamidophenyl group, propionamidophenyl group, dodecyloylamidophenyl group, etc.)
Is mentioned.

R ¹ and R ² may represent an organic residue which is bonded to form a ring with a nitrogen atom. The organic residue may further contain a hetero atom (eg, oxygen atom, nitrogen atom, sulfur atom, etc.). Examples of the formed cyclic group include a morpholino group, a piperidino group, a pyridinyl group, an imidazolyl group, and a quinolinyl group. A plurality of amino groups may be contained in the molecule of the monomer (B). The resin particles of the present invention contain an amino group-containing monomer (B) as a copolymerization component, so that the particles become electrophoretic, the charge amount of the particles increases, and the environmental conditions (low temperature / low humidity to The change in the charging characteristics is remarkably reduced even by the fluctuation of high temperature and high humidity or the storage for a long period of time, and as a result, the formed image has stable image quality. Monomer (B)
Is preferably 1 to 45 with respect to the total amount of the monomer (A).
Mass%, more preferably 5 to 30 mass%.

Specific examples of the monomer (B) are shown below.
The present invention is not limited to these.

[0033]

[Chemical 8]

Next, the monofunctional monomer (C) used in the present invention will be described. The monofunctional monomer (C) is-
It is a monomer copolymerizable with the monomer (A), containing at least one acidic group selected from PO ₃ H ₂ group, —SO ₃ H group and —SO ₂ H group. The monomer (C) may contain a plurality of the above acidic groups in the molecule. The monomer (C) supplements the effect of the monomer (B), further improves the charging characteristics of the resin particles, and acts to always provide a stable and excellent image quality. Monomer (C) is monomer (B) / monomer (C)
The molar ratio is preferably 0.2 to 2.5, more preferably 0.5 to 2.0.

Specific examples of the monomer (C) are shown below.
The present invention is not limited to these.

[0036]

[Chemical 9]

[0037]

[Chemical 10]

Next, the monofunctional monomer (D) used in the present invention will be described. The monomer (D) is a monofunctional monomer copolymerizable with the monomer (A) containing a fluorine atom and / or a silicon atom in the side chain substituent of the polymerizable double bond group. is there.

Examples of the substituent containing a fluorine atom include the following monovalent or divalent organic residues. −
_{C n (F) 2n + 1} (n is 1 to 22 integer), - CFH _{2,
-CFHCl, -CFCl 2, -CF 2 Cl} , - (C
F ₂ ) _m CF ₂ H (m is 0 or an integer of 1 to 17), -CF
_2- , -CFH-, -CFCl-

These fluorine atom-containing organic residues may be constituted in combination, and in that case, they may be directly bonded or may be combined via another linking group. The linking radicals, specifically include divalent organic residues, -O -, - S -, - N (g 1) -, - CO
-, - SO -, - SO 2 -, - COO -, - OCO-,
-CONHCO -, - NHCONH -, - CON (g 1)
A divalent aliphatic group or a divalent aromatic group which may have a bonding group selected from —, —SO ₂ N (g ¹ ) — and the like,
Alternatively, an organic residue composed of a combination of these divalent residues can be mentioned. Here, g ¹ represents an alkyl group having 1 to 3 carbon atoms.

As the substituent containing a silicon atom, those containing the following siloxane structure (or silyloxy structure) or silyl group are preferable.

[0042]

[Chemical 11]

In the above structure, R¹¹And R¹²And R
¹³, R¹⁴And R¹⁵Can be the same or different from each other
Each represents an aliphatic group, an aromatic group or a heterocyclic group. R¹¹~ R¹⁵
Each preferably has 1 to 18 carbon atoms which may be substituted.
Linear or branched alkyl group (eg, methyl group, ethyl
Group, propyl group, butyl group, hexyl group, heptyl group,
Octyl group, nonyl group, decyl group, dodecyl group, tridecyl group
Syl group, tetradecyl group, hexadecyl group, octadecyl
Group, 2-fluoroethyl group, trifluoromethyl group, 2-
Chloroethyl group, 2-bromoethyl group, 2-cyanoethyl
Group, 2-methoxycarbonylethyl group, 2-methoxy
Ethyl group, 3-bromopropyl group, 2-methylcarboni
Ruethyl group, 2,3-dimethoxypropyl group, fluorinated group
Rukyl group [eg-(CH₂)_hC_iF_{2i + 1}Group (however, h is 1
~ Integer of 6, i represents an integer of 1 to 12) group,-(CH
₂)_h-(CF₂)_j-R¹⁶Group (where j is 0 or an integer of 1 to 12)
Number, R¹⁶The group is an alkyl group having 1 to 12 carbon atoms, -CF
₂H, -CFH₂, -CF₃Represents), -CH (C
F₃)₂, -CF₂Cl, -CFCl₂, -CFClH,
-CF (CF₃) OC_iF_{2i + 1}, -OC_iF_{2i + 1}, -C (C
F₃)₂OC_iF _{2i + 1}etc〕,

An alkenyl group having 4 to 18 carbon atoms which may be substituted (eg, 2-methyl-1-propenyl group, 2-
Butenyl group, 2-pentenyl group, 3-methyl-2-pentenyl group, 1-pentenyl group, 1-hexenyl group, 2-
Hexenyl group, 4-methyl-2-hexenyl group, decenyl group, dodecenyl group, tridecenyl group, hexadecenyl group, octadecenyl group, linolenyl group, etc.), carbon number 7 to
12 optionally substituted aralkyl groups (eg, benzyl group, phenethyl group, 3-phenylpropyl group, naphthylmethyl group, 2-naphthylethyl group, chlorobenzyl group, bromobenzyl group, methylbenzyl group, ethylbenzyl group, Methoxybenzyl group, dimethylbenzyl group, dimethoxybenzyl group, etc.), alicyclic group having 5 to 8 carbon atoms which may be substituted (for example, cyclopentyl group, cyclohexyl group, 2-cyclohexylethyl group, 2-cyclopentylethyl group, Polyfluorohexyl group, methylcyclohexyl group, methoxycyclohexyl group, etc.), 6 to 6 carbon atoms
12 optionally substituted aromatic groups (eg, phenyl group, naphthyl group, tolyl group, xylyl group, propylphenyl group, butylphenyl group, octylphenyl group, dodecylphenyl group, methoxyphenyl group, ethoxyphenyl group, butoxy group Phenyl group, fluorophenyl group, chlorophenyl group, difluorophenyl group, bromophenyl group,
Cyanophenyl group, acetylphenyl group, methoxycarbonylphenyl group, ethoxycarbonylphenyl group, butoxycarbonylphenyl group, acetamidophenyl group, propioamidophenyl group, trifluoromethylphenyl group, etc.), or nitrogen atom, oxygen atom, sulfur atom A heterocyclic group which may be condensed with at least one atom selected from (for example, the heterocycle includes pyran ring, furan ring, thiophene ring, morpholine ring, pyrrole ring, thiazole ring, oxazole ring, pyridine ring) , Piperidine ring, pyrrolidone ring, benzothiazole ring, benzoxazole ring, quinoline ring, tetrahydrofuran ring and the like).

Particularly preferably, R¹¹And R¹²One of
Substituent of R, and R¹³, R¹⁴And R ¹⁵Two or more in
Each of the substituents is composed of an alkyl group or an alkenyl group.
Is Rukoto. Fluorine atom-containing substituents and silicon atom-containing
A plurality of substituents are contained in the molecule of the monomer (D).
Good. Monomer (D) is better than the total amount of all monomers.
It is preferably 1 to 15% by mass, more preferably 2 to 10% by mass.
% Used.

Specific examples of the monomer (D) are shown below.
The present invention is not limited to this.

[0047]

[Chemical 12]

[0048]

[Chemical 13]

[0049]

[Chemical 14] Next, the dispersion stabilizing resin (P) used in the present invention will be described.

In the present invention, the dispersion stabilizing resin (P) used to form a non-aqueous solvent-insoluble polymer produced by polymerizing a monomer in a non-aqueous solvent into a stable resin dispersion is
At least one polymerization component represented by the general formula (PI) is used.
It is a copolymer containing seeds and dispersed in a colloidal form in the non-aqueous solvent. The copolymer is a block composed of a block containing at least a polymerization component soluble in a non-aqueous solvent represented by the general formula (PI) (hereinafter referred to as block A) and a block not containing it (hereinafter referred to as block B). It is a copolymer and includes an AB block type (including ABA type and star type) and a graft type (also referred to as comb type). That is, the block A part is a part soluble in the non-aqueous solvent, the block B is an insoluble part in the non-aqueous solvent, and such a block copolymer of the soluble part and the insoluble part is used as the dispersion stabilizing resin (P). This makes it easy to disperse the dispersion stabilizing resin (P) in a colloidal form.

The dispersion stabilizing resin (P) of the present invention is preferably a resin which is dispersed in the non-aqueous solvent in a colloidal form having an average particle size of 0.15 μm or less, more preferably 0.1 μm or less. is there. The polymerization pattern of the block copolymer in the dispersion stabilizing resin (P) of the present invention is illustrated below.

[0052]

[Chemical 15]

Next, the repeating unit represented by the general formula (PI), which is the main component in the block A of the dispersion stabilizing resin of the present invention, will be described. -V ⁰ in the general formula (PI) -
Preferably represents -COO-, -OCO- or -O-. L preferably represents an alkyl group or an alkenyl group having 10 or more carbon atoms, which may be linear or branched. Specific examples thereof include a decyl group, a dodecyl group, a tridecyl group, a tetradecyl group, a hexadecyl group, an octadecyl group, an eicosanyl group, a docosanyl group, a decenyl group, a dodecenyl group, a tridecenyl group, a hexadecenyl group, an octadecenyl group, and a linolel group.

B ¹ and b ² may be the same or different from each other, preferably a hydrogen atom, a halogen atom (eg chlorine atom, bromine atom etc.), a cyano group, a carbon atom 1 to
3 alkyl group (eg, methyl group, ethyl group, propyl group, etc.), —COO-Z ¹ or —CH ₂ COO-Z ¹ [Z ¹
Represents a hydrogen atom or an optionally substituted hydrocarbon group having 22 or less carbon atoms (for example, an alkyl group, an alkenyl group, an aralkyl group, an alicyclic group, an aryl group, etc.).

Z ¹ is specifically a hydrogen atom, and as a preferable hydrocarbon group, an optionally substituted alkyl group having 1 to 22 carbon atoms (eg, methyl group, ethyl group, propyl group, butyl group) is preferable. Group, heptyl group, hexyl group, octyl group, nonyl group, decyl group, dodecyl group, tridecyl group, tetradecyl group, hexadecyl group, octadecyl group, eicosanyl group, docosanyl group, 2-chloroethyl group, 2-bromoethyl group, 2- Cyanoethyl group, 2-methoxycarbonylethyl group, 2-methoxyethyl group, 3
-Bromopropyl group, etc., an alkenyl group having 4 to 18 carbon atoms which may be substituted (for example, 2-methyl-1-propenyl group, 2-butenyl group, 2-pentenyl group, 3-methyl-2-pentenyl group) , 1-pentenyl group, 1-hexenyl group, 2-hexenyl group, 4-methyl-2-hexenyl group, decenyl group, dodecenyl group, tridecenyl group,
Hexadecenyl group, octadecenyl group, linolel group, etc.), aralkyl group having 7 to 12 carbon atoms which may be substituted (for example, benzyl group, phenethyl group, 3-phenylpropyl group, naphthylmethyl group, 2-naphthylethyl group, chloro) Benzyl group, bromobenzyl group, methylbenzyl group, ethylbenzyl group, methoxybenzyl group, dimethylbenzyl group, dimethoxybenzyl group, etc.), an alicyclic group having 5 to 8 carbon atoms which may be substituted (eg, cyclohexyl group, 2-cyclohexylethyl group, 2-cyclopentylethyl group, etc.) and optionally substituted aromatic group having 6 to 12 carbon atoms (eg, phenyl group, naphthyl group, tolyl group, xylyl group, propylphenyl group, butylphenyl) Group, octylphenyl group, dodecylphenyl group, methoxyphenyl group, etoxy Phenyl 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, dodecyloylamidophenyl group, etc.) To be

In the block A part, other repeating unit may be contained as a copolymerization component in addition to the repeating unit represented by the general formula (PI). The other copolymerization component may be any compound as long as it is a monomer copolymerizable with the monomer corresponding to the repeating unit of the general formula (PI).
However, it is preferable that the other components are not contained, and at most 20% by mass or less, more preferably 10% by mass or less in the block A is used. If it exceeds 20% by mass, the dispersion stability of the colloidal dispersed resin particles deteriorates. In the block A, the repeating unit represented by the general formula (PI) may be used in combination of two or more kinds.

The polymer component constituting the block B of the dispersion stabilizing resin used in the present invention includes a polymer component corresponding to the monofunctional monomer (A), a phosphono group and a carboxyl group. Group, sulfo group, hydroxyl group, formyl group, amino group, -P (= O) (OH) R ³¹ group [R
³¹ represents -R ³² group or -OR ³² group, R ³² represents a hydrocarbon group], -CONR ³³ R ³⁴ group, -SO ₂ NR ³³ R ³⁴ group [R ³³ and R ³⁴ are each independently , A hydrogen atom or a hydrocarbon group] and a polymer component containing at least one polar group selected from cyclic acid anhydride-containing groups.

Each of the above-mentioned hydrocarbon groups represents a hydrocarbon group having 1 to 10 carbon atoms. The hydrocarbon group for R ³² is preferably an optionally substituted aliphatic group having 1 to 8 carbon atoms (eg, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, butenyl group, pentenyl group). , A hexenyl group, a 2-chloroethyl group, a 2-cyanoethyl group, a cyclopentyl group, a cyclohexyl group, a benzyl group, a phenethyl group, a chlorobenzyl group, a bromobenzyl group, and the like, and an aromatic group which may be substituted (for example, a phenyl group, Tolyl group, xylyl group, mesityl group, chlorophenyl group,
Bromophenyl group, methoxyphenyl group, cyanophenyl group, etc.).

The cyclic acid anhydride-containing group is a group containing at least one cyclic acid anhydride, and the cyclic acid anhydride to be contained is an aliphatic dicarboxylic acid anhydride or an aromatic dicarboxylic acid anhydride. Things can be mentioned. Examples of the aliphatic dicarboxylic acid anhydride include succinic anhydride, glutaconic anhydride, maleic anhydride, cyclopentane-1,2.
-Dicarboxylic acid anhydride, cyclohexane-1,2-dicarboxylic acid anhydride, cyclohexene-1,2-dicarboxylic acid anhydride, 2,3-bicyclo [2,2,2] octanedicarboxylic acid anhydride, and the like, These aliphatic dicarboxylic acid anhydrides may be substituted with, for example, a halogen atom such as a chlorine atom or a bromine atom, an alkyl group such as a methyl group, an ethyl group, a butyl group or a hexyl group. Further, examples of aromatic dicarboxylic acid anhydrides include phthalic anhydride,
Naphthalene-dicarboxylic acid anhydride, pyridine-dicarboxylic acid anhydride, thiophene-dicarboxylic acid anhydride and the like, and these aromatic dicarboxylic acid anhydrides, for example,
Chlorine atom, halogen atom such as bromine atom, methyl group, ethyl group, propyl group, butyl group, alkyl group such as hydroxyl group, cyano group, nitro group, alkoxycarbonyl group (as the alkoxy group, for example, a methoxy group, Ethoxy group, etc.) and the like.

The block B part is preferably a polymer component corresponding to the monofunctional monomer (A). When the above-mentioned specific polar group-containing polymer component is contained, it is preferably not more than 30 parts by mass of the total polymer component in the block B part. If it exceeds 30 parts by mass, the ejection response of the ink containing the dispersed resin particle dispersion of the present invention may be adversely affected.

The mass average molecular weight (Mw) of the dispersion stabilizing resin (P) of the present invention is preferably 2 × 10 ⁴ to 1 × 10 ⁶ , and more preferably 3 × 10 ⁴ to 1 × 10 ⁵ . . The composition ratio of the block A part and the block B part in the dispersion stabilizing resin (P) of the present invention is preferably 30/70 to 90/10 (mass ratio), and more preferably 40/60 to 80 /.
20 (mass ratio).

The case where the dispersion stabilizing resin (P) of the present invention is a star block copolymer will be described in more detail. The star-type block polymer is formed by binding at least three polymer chains composed of block A and block B shown below.

[0063]

[Chemical 16]

Here, each polymer chain is composed of the same contents, and the order of arrangement in the polymer chains of block A and block B is such that the end of the polymer main chain of block A which is connected to block B of the main chain. It is formed by binding to an organic molecule at one end on the side opposite to.

In the above, X represents an organic molecule,
(A) represents block A, (B) represents block B,
(A)-(B) represents a polymer chain. Also, such AB
The upper limit of the type block polymer chains contained in the organic molecule is at most 15, usually about 10. The organic molecule formed by binding at least three polymer chains is not particularly limited as long as the molecular weight of the molecule is 1,000 or less. Examples include the trivalent hydrocarbon residues described below.

[0066]

[Chemical 17]

[0067]

[Chemical 18]

The block copolymer (P) can be synthesized by a conventionally known block copolymer synthesizing method of a monomer having a polymerizable dipolymerization bond group. For example, one of them is a polymerization reaction using a carbanion as an initiator. Specifically, M. Morton, TE Helminiak et al.
“J. Polym. Sci.” 57, 471 (1962), B. Gordon III,
M, Blumenthal, JE Loftus et al “Polym. Bul
l. ”11, 349 (1984), RB Bates, WA Beavers et a
It can be synthesized according to the method described in “J. Org. Chem.” 44, 3800 (1979). However, when this reaction is used, the "specific polar group" of the present invention is used as a protected functional group to polymerize, and then the protective group is removed. The protection of the specific polar group of the invention with a protecting group and the elimination of the protecting group (deprotection reaction) can be easily carried out by utilizing the conventionally known knowledge. For example, various references are given in the above cited document, and further, Yoshio Iwakura, Keisuke Kurita "Reactive Polymer" Kodansha Ltd. (1977), TM Greene "Pr.
otective Groups in Organic Synthesis ”(John Wiley
& Sons, 1981), JFW McOmic “Protective Gro
ups in Organic Chemistry ”(Plenum Press, 1973)
The method described in detail in the review article can be selected as appropriate.

As another method, a monomer of the present invention which does not protect a specific polar group is used, and a compound containing a dithiocarbament group and / or a compound containing a xanthate group is used as an initiator. It can also be synthesized by performing a polymerization reaction under light irradiation. For example, Takayuki Otsu "Polymer" 3
7, 248 (1988), Shunichi Hinomori, Ryuichi Otsu “Polym. Rep. Ja
p. "37, 3508 (1988), Japanese Unexamined Patent Publication No. 64-111, Japanese Unexamined Patent Publication No. 64-26619, Nobuyuki Azuma et al.," Polymer Preprints, "
Japan ”36 (6), 1511 (1987), M. Niwa, N. Higashi
et al “J. Macromol. Sci. Chem.” A24 (5), 567 (19
87) and the like.

Within the above range, the dispersion resin particles in the oil-based ink of the present invention are excellent in dispersion stability, re-dispersion stability and storage stability, and the rapid fixing property after image formation is good. In addition, it retains sufficient strength during printing and exhibits high printing performance. At the same time, it exhibits very stable dispersibility, and even if it is used repeatedly for a long time in the recording apparatus, it has good dispersibility and is easy to re-disperse, and it is completely adhered to each part of the apparatus to cause stains. unacceptable.

Furthermore, when fixing was carried out by rapid processing such as heating after the formation of an ink image, a strong coating was easily formed on the surface of the lithographic printing plate support, and good fixing properties were exhibited. As a result, it is possible to print a large number of sheets (high printing durability) even in offset printing. The oil-based ink of the present invention which brings about the above effects is made possible by the insoluble latex provided by the present invention.

Such remarkable performance-improving effect of the present invention depends on the copolymer (P) which is composed of specific blocks as constituents and is dispersed in a non-aqueous solvent in a colloidal state. Is. That is, the dispersion stabilizing resin (P) of the present invention has a block A composed of a polymer component containing a linear aliphatic group having a high affinity for the non-aqueous solvent and an affinity for the non-aqueous solvent. Is a copolymer consisting of a polymer chain of a block bound to a block B composed of a polymerization component having a small affinity for the insoluble monomer (A) and being colloidal in a non-aqueous carrier liquid. It is characterized by being dispersed in. As a result, in the polymerization granulation reaction of the dispersed resin particles, the block B portion is sufficiently adsorbed by physicochemical interaction during the polymerization granulation, and the block portion having a large affinity for the non-aqueous dispersion medium is the solvent. On the other hand, since there is a polymer chain that is sufficiently solvated with respect to the polymer chain and sufficiently acts on the steric repulsion effect, the adsorption effect and the steric repulsion effect are sufficiently efficiently expressed, and thus the effect is exerted in the present invention. Presumed to be done.

On the other hand, in the conventionally known random copolymer of the polymer component used in the block A and the polymer component used in the block B, the component serving as the adsorbing portion is composed of a solvating component. Since they are randomly bonded in the polymer chain, they are not sufficiently adsorbed on the dispersed resin particles, and the adsorption pattern is looped, which also hinders the steric repulsion effect, resulting in insufficient dispersion stability. There wasn't. Furthermore, A composed of block A and block B
By using the -B type block copolymer, the effect of improving the dispersion stability was recognized as compared with the above random copolymer. However, the block copolymer (P) obtained by colloidally dispersing in the non-aqueous solvent of the present invention is more adsorbed on the dispersed particles than the dispersion stabilizing resin composed of the block copolymer soluble in the solvent. It was found to be excellent and the dispersibility was extremely excellent.

As described above, the oil-based ink of the present invention is improved in dispersion stability and the like and various problems are improved by using the block copolymer having a specific block bond in combination. .

To produce the dispersed resin particles used in the present invention, generally, the dispersion stabilizing resin (P) as described above,
Polymerization of monomer (A), monomer (B), monomer (C), and monomer (D) in a non-aqueous solvent such as benzoyl peroxide, azobisisobutyronitrile, and butyllithium. The polymerization may be carried out by heating in the presence of an initiator. Specifically, a polymerization initiator is added to a mixed solution of the dispersion stabilizing resin (P), the monomer (A), the monomer (B), the monomer (C), and the monomer (D). Method of addition, monomer (A), monomer (B), monomer (C), and monomer (D) together with a polymerization initiator in a solution in which the dispersion stabilizing resin (P) is dissolved How to drop
Alternatively, in a solution in which the dispersion stabilizing resin (P) is dissolved,
A mixture of half amount of monomer (A) and monomer (B) and half amount of monomer (A), monomer (C), monomer (D) and polymerization initiator are added dropwise at the same time. There are ways to do it,
It can be manufactured by any method. The monomer (A), the monomer (B), the monomer (C), and the monomer (D) used in the present invention are copolymerized by a polymerization reaction to form a resin insoluble in a non-aqueous solvent. Become.

The total amount of the monomer (A), the monomer (B), the monomer (C) and the monomer (D) is preferably 10 to 100 relative to 100 parts by mass of the non-aqueous solvent. It is about 10 parts by mass, more preferably 10 to 80 parts by mass. The dispersion stabilizing resin (P) is preferably about 3 to 25 parts by weight, and more preferably 5 to 20 parts by weight, based on 100 parts by weight of all the monomers used above. The amount of the polymerization initiator is appropriately about 0.1 to 10% by mass based on all monomers. Also,
The polymerization temperature is preferably about 40 to 180 ° C, more preferably 50 to 120 ° C. The reaction time is preferably about 3 to 15 hours.

When a polar solvent such as the above-mentioned alcohols, ketones, ethers and esters is used in combination in the non-aqueous solvent used in the reaction, or the unreacted monomer of the polymerized granulation is When it remains, it is preferably removed by heating it to a temperature above the boiling point of the polar solvent or monomer and distilling it off, or by distilling it off under reduced pressure.

The non-aqueous dispersion resin particles produced according to the present invention as described above exist as fine particles having a uniform particle size distribution. The average particle size is preferably 0.15
˜1.5 μm, more preferably 0.2 to 1.0 μm. This particle size is CAPA-500 (Horiba Ltd.)
Manufactured). Further, the dispersed resin particles of the present invention show positive chargeability due to the action of the polymerization components corresponding to the monomer (B) and the monomer (C).

The weight average molecular weight (M
w) (polystyrene conversion value by GPC method) is preferably 5 × 10 ³ to 1 × 10 ⁶ , and more preferably 8 × 1.
It is 0 ^{3 to} 5 × 10 ⁵ . As the thermophysical properties, the glass transition point is 0 ° C to 80 ° C or the softening point is 35 ° C to 12 ° C.
0 ° C is preferable, and more preferably the glass transition point is 10 ° C.
˜70 ° C. or softening point is 38 ° C. to 90 ° C.

The liquid developer of the present invention is excellent in dispersibility, storability, stability and redispersibility of dispersed resin particles, has good fixability after image formation, and maintains sufficient image strength during printing. Shows high printing durability. That is, it shows very stable dispersibility,
In particular, in the developing device, the dispersibility is good even after repeated use for a long time, and the redispersion is easy, and it is not observed that it adheres to each part of the device and causes stains.

Further, because of its good fixing property, when fixing is carried out by rapid processing such as heating after image formation, a strong coating film is easily formed on the surface of the lithographic printing plate precursor. As a result, even in offset printing, printing on a large number of sheets (high printing durability) becomes possible. The liquid developer of the present invention which brings about the above effects is made possible by the non-aqueous latex provided by the present invention.

The liquid developer of the present invention comprises a charge control agent (C
D) is used. Charge control agents are well known in the technical field of liquid developers for electrostatic photography, and specifically, "Development and practical use of recent electrophotographic development systems and toner materials" 139-1
48 pages, “The Basics and Applications of Electrophotographic Technology” edited by The Institute of Electrophotography 49
The compounds described on pages 7 to 505 (Corona Publishing, 1988), Yuji Harazaki “Electrophotography” 16 (N0.2), 44 (1977) and the like can be used. Preferred charge control agents include
Examples thereof include metal soaps, organic phosphoric acid or salts thereof, organic sulfonic acids or salts thereof, and amphoteric surface active compounds.

For example, as metal soaps, fatty acids having 6 to 24 carbon atoms (for example, 2-ethylhexynic acid, 2-
Ethylcaproic acid, lauric acid, palmitic acid, elaidic acid, linoleic acid, ricinoleic acid, oleic acid, stearic acid, enanthic acid, naphthenic acid, ethylenediaminetetraacetic acid, etc.), resin acid, dialkylsuccinic acid, alkylphthalic acid, alkylsalicylic acid Metal salt such as Na, K, Li, B, Al, Ti, Ca
Pb, Mn, Co, Zn, Mg, Ce, Ag, Cd, Z
r, Cu, Fe, Ba, etc.) (eg US Pat.
No. 11, 936, No. 3, 900, 412, Japanese Patent Publication No. 49
-27707, JP-A-51-37651, JP-A-52-
38937, 52-107837, 53-12.
3138, etc.).

Examples of the organic phosphoric acid or salts thereof include mono-, di- or trialkyl phosphoric acid or dialkyldithiophosphoric acid composed of an alkyl group having 3 to 18 carbon atoms (for example, British Patents 1, 411, 739, 1, 276,3
No. 63). Examples of the organic sulfonic acids or salts thereof include long-chain aliphatic sulfonic acids, long-chain alkylbenzene sulfonic acids, dialkyl sulfosuccinic acids and the like or metal salts thereof (for example, Japanese Patent Publication No. 47-3712).
No. 8, JP-A Nos. 53-123138 and 51-4743.
No. 7, No. 50-79640, No. 53-30340, etc.).

As the amphoteric surface active compound, lecithin,
Phospholipids such as kephalin (for example, Japanese Examined Patent Publication No. 51-470)
46, etc.), β containing an alkyl group having 8 or more carbon atoms
-Alanines (for example, described in JP-A Nos. 50-17642 and 49-17741), metal complexes of β-diketones (for example, described in JP-B-49-27707),
A copolymer containing a maleic acid half amide component (for example,
Japanese Patent Publication No. 6-19596, No. 6-19595, No. 6-
No. 23865).

The charge control agents can be used alone or in combination of two or more kinds. The charge control agent is added in an amount of 0.001 to 1,000 parts by mass of the non-aqueous solvent that is a carrier liquid.
It is preferable to use about 1.0 part by mass.

As described above, the dispersed resin particles of the present invention have positive chargeability themselves, but a sufficient amount of charge can be maintained by further using a charge control agent. Further, it is possible to maintain a state in which the ratio of the charge amount of dispersed particles (charge fraction of particles) in the liquid developer is extremely high. The charge fraction of particles will be described in detail in Examples.

As a result, in the liquid developer of the present invention, the charge amount of the dispersed particles is selectively increased, and the particles quickly and electrically correspond to the electrostatic latent image on the electrostatic recording body. It migrates and adheres to form a high-definition image. By the way, even if the total charge amount of the liquid developer is high, if the charge amount of the carrier liquid is large, these soluble ionic components adhere to the electrostatic latent image, and the adhesion of charged particles that should originally adhere is hindered. Or, the adhesion of particles is reduced due to the reduction of the charge of the latent image, and as a result, the reproduction of the fine dots becomes insufficient, or the edge portion of the image portion bleeds or flows, resulting in an image defect. Further, the liquid developer of the present invention is almost selectively and strongly retained on the particles, so that it is hardly affected by moisture due to a change in humidity, and the plate making environment changes from low humidity to high humidity. Even in this case, it is possible to stably form an image with good reproducibility.
Furthermore, the liquid developer of the present invention may be stored for a long period of time or under high temperature / high humidity (for example, 35 ° C./80% RH).
Even if plate making is carried out, the performance is completely the same as the case of using a fresh product immediately after the production of the liquid developer. This is because the charge characteristics of the liquid developer of the present invention, particularly the chargeability of positively charged particles, are stably maintained, and sufficient dispersibility is maintained without causing aggregation or precipitation between dispersed particles. It is believed that

If desired, various additives may be added to the liquid developer of the present invention, and the upper limit of the total amount of these additives is restricted by the electric resistance of the liquid developer. That is, the electric resistance of the ink with the dispersed particles removed is 10
^If it is lower than ⁹ Ωcm, it becomes difficult to obtain a good quality continuous tone image. Therefore, it is desirable to control the addition amount of each additive within this limit.

In the liquid developer of the present invention, it is preferable to include a coloring material as a coloring component together with the above-mentioned dispersed resin particles in order to inspect the plate after plate making. As the color material, any pigment and dye conventionally used in oil-based ink compositions or liquid developers for electrostatic photography can be used.

As the pigment, regardless of whether it is an inorganic pigment or an organic pigment, those generally used in the technical field of printing can be used. Specifically, for example, carbon black, cadmium red, molybdenum red, chrome yellow, cadmium yellow, titanium yellow, chromium oxide, pyridian, cobalt green, ultramarine blue, Prussian blue, cobalt blue, azo pigments, phthalocyanine pigments. , Quinacridone pigments, isoindolinone pigments, dioxazine pigments, slene pigments, perylene pigments, perinone pigments, thioindigo pigments, quinophthalone pigments, metal complex pigments, etc. Can be used without.

As the dyes, azo dyes, metal complex salt dyes,
Naphthol dye, anthraquinone dye, indigo dye,
Oil-soluble dyes such as carbonium dyes, quinone imine dyes, xanthene dyes, cyanine dyes, quinoline dyes, nitro dyes, nitroso dyes, benzoquinone dyes, naphthoquinone dyes, phthalocyanine dyes and metal phthalocyanine dyes are preferable.

These pigments and dyes may be used alone or in appropriate combination, but they are contained in the range of 0.05 to 5 mass% with respect to the entire liquid developer. Is desirable.

These coloring materials may be dispersed in the non-aqueous solvent as the coloring materials themselves as the dispersed particles in addition to the dispersed resin particles, or may be contained in the dispersed resin particles. As one of the methods for incorporating it, there is a method of dyeing a dispersed resin material with an appropriate dye as described in JP-A-57-48738. As another method, JP-A-53-54
As disclosed in No. 029, there is a method of chemically bonding a dispersion resin and a dye. Also, Japanese Patent Publication No.
As described in No. 2955 and the like, there is a method in which a dye-containing copolymer is prepared by using a dye-containing monomer in advance in the production by the polymerization granulation method. The production of a printing plate by the electrophotographic method using the liquid developer for electrostatic photography of the present invention can be carried out by a conventional method. Further, the liquid developer of the present invention,
It can also be used for ordinary electrostatographic copying.

[0095]

EXAMPLES The present invention will be described in more detail below with reference to production examples and examples of resin particles used in the present invention, but the present invention is not limited thereto.

Synthesis Example of Dispersion Stabilizing Resin (P) 1: Resin (P-1) Methyl Methacrylate 50 g, Ethyl Acrylate 50
g, a mixture of 7.8 g of an initiator (I-1) having the following structure and 100 g of tetrahydrofuran under a nitrogen stream at a temperature of 50 ° C.
Warmed to. 10c of this solution with 400W high pressure mercury lamp
Light was irradiated from a distance of m through a glass filter for 8 hours to perform photopolymerization. The polymer was reprecipitated in 1 liter of methanol, and the precipitate was collected and dried. Next, the above polymer 5
A mixed solution of 5 g, 45 g of stearyl methacrylate and 100 g of tetrahydrofuran was heated again to a temperature of 50 ° C. under a nitrogen stream. Next, in the same manner as above, after performing light irradiation for 16 hours, the obtained reaction product was treated with methanol 1.5
It is reprecipitated in liter, the precipitate is collected, dried and the weight average molecular weight [Mw: Mw is a value by polystyrene conversion GPO method (GPC: size exclusion chromatography)] is 6 × 10 ⁴ at a yield of 80 g. A polymer of Moreover, 5% by mass of the obtained resin and Isopar H (manufactured by Exxon)
After thoroughly stirring the mixture, the mixture became a bluish-white liquid. A sample was prepared from this solution, and fine particles with an average particle size of 0.14 μm were observed from a scanning electron microscope (hereinafter referred to as SEM) photograph.

[0097]

[Chemical 19]

Synthesis Example 2 of Dispersion Stabilizing Resin (P): Resin (P-2) A mixture of 50 g of octadecyl acrylate, 10.0 g of the initiator (I-2) having the following structure and 50 g of tetrahydrofuran was heated under a nitrogen stream at temperature. Warmed to 50 ° C. This solution was irradiated with light from a high pressure mercury lamp of 400 W at a distance of 10 cm through a glass filter for 8 hours to perform photopolymerization. The polymer was reprecipitated in 1 liter of methanol, and the precipitate was collected and dried. Next, a mixed solution of 30 g of the above polymer, 36 g of methyl acrylate, 4 g of acrylic acid and 70 g of tetrahydrofuran was heated again to a temperature of 50 ° C. under a nitrogen stream. Next, after performing light irradiation for 8 hours in the same manner as above, the obtained reaction product was reprecipitated in 1.5 liter of methanol, and the precipitate was collected and dried. Further, a mixed solution of 35 g of this polymer, 15 g of octadecyl acrylate and 50 g of tetrahydrofuran was heated again to a temperature of 50 ° C. under a nitrogen stream. Then, after performing light irradiation for 8 hours in the same manner as above, the obtained reaction product was reprecipitated in 1.5 liters of methanol, and the precipitate was collected and dried to obtain a yield of 4
A polymer having an Mw of 6.5 × 10 ⁴ was obtained with 2 g. In the same manner as in Synthesis Example 1, particles having an average particle size of 0.13 μm were found by SEM photograph observation of a sample of the Isopar H mixture.

[0099]

[Chemical 20]

Synthesis Example 3 of dispersion stabilizing resin (P): Resin (P-3) 22 g of methyl methacrylate, 33 of methyl acrylate
g and a mixture of 45 g of a macromonomer (MM-1) having the following structure and 185 g of toluene at a temperature of 80 ° C. under a nitrogen stream.
Warmed to. 1.5 g of 2,2-azobisisobutyronitrile (abbreviation AIBN) was added to this mixed solution and reacted for 3 hours. Furthermore, 0.8 g of AIBN was added and reacted for 2 hours, and subsequently 0.5 g of AIBN was added, and then the temperature was raised to 85 ° C. and reacted for 3 hours. The resulting reaction product was a pale white, bright mixture. The reaction product was reprecipitated in 2 liters of methanol, and the precipitate was collected and dried to obtain a yield of 85 g.
Thus, a polymer having Mw of 4.5 × 10 ⁴ was obtained. Synthesis example (P-
As a result of SEM observation of the colloidal dispersion in the same manner as in 1), it was a particle of 0.10 μm.

[0101]

[Chemical 21]

Synthesis Examples 4 to 14 of Dispersion Stabilizing Resin (P):
Resin (P-4) to (P-14) Methyl methacrylate 35 g, methyl acrylate 55
A mixture of 0.01 mol of each initiator (I) shown in Table-A and 100 g of tetrahydrofuran was heated to 50 ° C under a nitrogen stream with respect to all monomers using g. This solution was irradiated with light for 12 hours to carry out a polymerization reaction in the same manner as in Synthesis Example 1. Next, 55 g of each polymer obtained, 45 g of tridecyl methacrylate and 12 g of tetrahydrofuran
The mixed solution containing 0 g was again heated to a temperature of 55 ° C. under a nitrogen stream.
Warmed to. Next, after performing light irradiation for 16 hours in the same manner as above, the obtained reaction product was reprecipitated in 1.5 liter of methanol, and the precipitate was collected and dried. Yield 60 ~
80 g of each polymer having Mw of ⁴ × 10 ^{4 to} 7 × 10 ⁴ was obtained.
As a result of SEM observation of the colloidal dispersion of each polymer, particles of each polymer in Isopar H were 0.10 to 0.15.
was μm.

Synthesis Examples 15 to 1 of Dispersion Stabilizing Resin (P)
8: Resins (P-15) to (P-18) In Synthesis Example 1 of the resin (P) for dispersion stabilization, instead of 50 g of methyl methacrylate, 50 g of ethyl acrylate and 45 g of stearyl methacrylate, the block copolymer shown in Table-B was used. Each copolymer was synthesized in the same manner as in Synthesis Example 1 except that a monomer corresponding to each repeating unit of the united body was used. The yield of the obtained polymer is 80 to 90 g and the Mw is 5
The range was ˜6 × 10 ⁴ . Further, the particle size of the fine particles of the 5 mass% mixture of Isopar H of each polymer is 0.10 to 0.1.
It was 5 μm.

[0104]

[Table 1]

[0105]

[Table 2]

[0106]

[Table 3]

[0107]

[Table 4]

Production Example of Resin Particles (L) 1: Resin Particles (L)
-1) A mixture of 12 g of a dispersion stabilizing resin (P-19) having the following structure and 280 g of Isopar G was heated to 70 ° C while stirring under a nitrogen stream. Methyl methacrylate 1
5 g, methyl acrylate 25.8 g, monomer (D-1) 4 g having the following structure, 2- (N, N-dimethylamino) ethyl methacrylate 6 g and 2,2-azobisisovaleronitrile (abbreviation: AI .V.N.), A mixture of 1.5 g and 15 g of methyl methacrylate, 30.2 g of methyl acrylate, 4 g of 3-sulfopropyl methacrylate and 10 g of ethanol were added dropwise at the same time in 1 hour and the mixture was stirred for 2 hours as it was.

Next, A. I. V. N. Add 1.0g and warm
The mixture was heated to 75 ° C. and stirred for 4 hours. I. B.
N. 0.8g and warm to 80 ° C and stir for 4 hours
did. Then raise the temperature to 100 ° C and reduce the pressure to 200mm.
Stir for 2 hours under Hg to remove ethanol and unreacted monomer
Was distilled off. After cooling, pass through a 200 mesh nylon cloth
Then, the obtained white dispersion had a polymerization rate of 99% and an average particle size of 0.
It was a 25 μm latex. Particle size is CAPA-50
0 (manufactured by HORIBA, Ltd.). The above white dispersion
Part of the centrifuge (rotation speed 1 × 10^Fourr. p. m. ,
The rotation time is 1 hour), and the settled resin particles are collected,
After drying, the resin particles have a mass average molecular weight (Mw) and
When the transition point (Tg) was measured, Mw was 2 × 10
^Five(Polystyrene conversion value by G.P.C.
,) And Tg was 41 ° C.

[0110]

[Chemical formula 22]

Production Example 2 of Resin Particles (L): Resin Particles (L)
-2) A mixture of 14 g of a dispersion stabilizing resin (P-20) having the following structure and 283 g of Isopar G was heated to 70 ° C while stirring under a nitrogen stream. Methyl methacrylate 2
0 g, 26 g of ethyl acrylate, 3 g of monomer (D-2) having the following structure, 8 g of 2- (N, N-diethylamino) ethyl methacrylate and A.I. I. V. N. , 1.5 g
And a mixture of 15 g of methyl methacrylate, 23.6 g of methyl acrylate, 4.4 g of 3-sulfopropyl acrylate and 10 g of ethanol were added dropwise at the same time in 1 hour, and the mixture was stirred for 2 hours as it was. Then A. I. V. N. 1.0 g was added and the mixture was heated to a temperature of 75 ° C. and stirred for 3 hours. I. B. N. 0.8 g was added, and the mixture was heated to a temperature of 80 ° C. and stirred for 3 hours. Then, the temperature was raised to 100 ° C., and the mixture was stirred under a reduced pressure of 200 mmHg for 2 hours to distill off ethanol and unreacted monomers. After cooling, it was passed through a nylon cloth of 200 mesh, and the obtained white dispersion was a latex having a polymerization rate of 99% and an average particle size of 0.23 μm. Mw of resin particles is 3 × 10 ⁵ , Tg41
It was ℃.

[0112]

[Chemical formula 23]

[0113]

[Chemical formula 24]

Production Examples 3 to 5 of Resin Particles (L): Resin Particles (L-3) to (L-5) In Production Example 1 of resin particles (L), 10 g of the dispersion stabilizing resin (P-19) and Instead of 6 g of 2 (N, N-dimethylamino) ethyl methacrylate and 4 g of the monomer (D-1), 11 g of the dispersion stabilizing resin (P-1) having the above structure
Each particle was produced in the same manner as in Production Example 1 except that 6 g of each monomer (B) and 4 g of monomer (D) shown in Table C below were used. The average particle size of the obtained particles is 0.20
It was a latex in the range of 0.25 μm. The resin particles had an Mw of 1 × 10 ^{5 to} 3 × 10 ⁵ and a Tg of 40 to 50 ° C.

[0115]

[Table 5]

Production Example 6 of Resin Particles (L): Resin Particles (L)
-6) A mixture of 12 g of the dispersion stabilizing resin (P-3) having the above structure and 280 g of Isopar G was heated to a temperature of 80 ° C while stirring under a nitrogen stream. To this, 15 g of styrene, 22 g of vinyltoluene, 3 g of monomer (D) having the following structure, 4-
8 g of (N, N-dimethylamino) methylstyrene and A.I. I. B. N. , 1.5 g of a mixture and 10 g of methyl methacrylate, 35.4 g of methyl acrylate and 4
-Sulfomethylstyrene 6.6g and ethanol 15g
The above mixture was added dropwise at the same time in 1 hour, and the mixture was stirred as it was for 2 hours. Then A. I. B. N. Add 1.0 g of 3
Stir for a period of time and then I. B. N. 0.8 g was added, and the mixture was heated to a temperature of 80 ° C. and stirred for 3 hours. Then set the temperature to 1
The temperature was raised to 00 ° C., and the mixture was stirred under a reduced pressure of 200 mmHg for 2 hours to distill off ethanol and unreacted monomers. After cooling 2
The resulting white dispersion was a latex having a polymerization rate of 98% and an average particle size of 0.28 μm. Mw of resin particles is 9 × 10 ⁴ , Tg is 48 ° C.
Met.

[0117]

[Chemical 25]

Production Examples 7 to 16 of Resin Particles (L): Resin Particles (L-7) to (L-16) In Production Example 1 of resin particles (L), 12 g of a resin (P-19) for dispersion stabilization and Instead of 4 g of the monomer (D-1), 12 g of the resin (P) for dispersion stabilization and 4 g of the monomer (D) shown in Table D below were used, and each particle was prepared in the same manner as in Production Example 1 above. Manufactured. The average particle size of the obtained particles was latex in the range of 0.20 to 0.25 μm.
Mw of resin particles is 8 × 10 ⁴ to 2 × 10 ⁵ , and Tg is 38.
It was each range of -42 degreeC.

[0119]

[Table 6]

Production Example 17 of Resin Particles (L): Resin Particles (L-17) A mixture of 10 g of the dispersion stabilizing resin (P-13) having the above structure and 380 g of Isopar G was stirred at a temperature of 75 ° C. under a nitrogen stream. Heated. 42g of vinyl acetate, 2
-(N, N-Dimethylamino) ethyl crotonate 7
g, 5 g of monomer (D-2), and A. I. B. N. ,
A mixture of 1.5 g of the mixture and 40 g of vinyl acetate, 6 g of 3-sulfopropyl crotonate and 10 g of ethanol were added dropwise at the same time in 30 minutes, and the mixture was stirred for 3.5 hours as it was. Then A. I. B. N. 1.0 g was added and the mixture was heated to a temperature of 80 ° C. and stirred for 3 hours. I. B.
N. Of 0.8 g was added and the mixture was heated to a temperature of 85 ° C. and stirred for 3 hours. Next, the temperature is raised to 100 ° C and the pressure reduction degree is 200 mm.
The mixture was stirred under Hg for 2 hours, and ethanol and unreacted monomers were distilled off. After cooling, it was passed through a nylon cloth of 200 mesh, and the obtained white dispersion had a polymerization rate of 90% and an average particle size of 0.1.
It was a 23 μm latex. The resin particles thus obtained had Mw of 8 × 10 ⁴ and Tg of 45 ° C.

Production Examples 18 to 23 of Resin Particles (L): Resin Particles (L-18) to (L-23) In Production Example 2 of resin particles (L), 14 g of dispersion stabilizing resin (P-20) Instead, 14 g of the resin (P) for dispersion stabilization shown in Table E below, 2- (N, N-diethylamino)
Instead of 8 g of ethyl methacrylate, 0.043 mol of the monomer (B) shown in the following table-E and 0.03 mol of monomer (D) of the following table-E instead of 4.4 g of 3-sulfopropyl acrylate. Each colored particle (L) was produced in the same manner as in Production Example 2 except that was used. Each of the obtained colored dispersions was a latex having an average particle size of 0.25 to 0.40 μm. .

[0122]

[Table 7]

Production Example of Comparative Resin Particles 1: Resin Particles (L
L-1) In Production Example 1 of resin particles (L), 15 g of methyl methacrylate and 4 g of 3-sulfopropyl pyrmethacrylate
Particles were produced in the same manner as in Production Example 1 of resin particles (L), except that was changed to 19 g of methyl methacrylate. The white dispersion obtained had a polymerization rate of 99% and an average particle size of 0.24 μm.
m latex. Mw of resin particles is 2 × 10
⁵ , Tg was 41 ° C.

Production Example 2 of Comparative Resin Particles: Resin Particles (L
L-2) Production example of resin particles (L) except that 15 g of methyl methacrylate and 6 g of 2- (N, N-dimethylamino) ethyl methacrylate were changed to 21 g of methyl methacrylate in Production Example 1 of resin particles (L). Particles were prepared as in 1. The obtained white dispersion was a latex having a polymerization rate of 99% and an average particle size of 0.23 μm. The resin particles had Mw of 2 × 10 ⁵ and Tg of 43 ° C.

Production Example 3 of Resin Particles for Comparison: Resin Particles (L
L-3) In Production Example 2 of resin particles (L), 15 g of methyl methacrylate and 4.4 of 3-sulfopropyl acrylate were used.
Particles were produced in the same manner as in Production Example 2 of resin particles (L) except that g was changed to 19.4 g of methyl methacrylate. The obtained white dispersion was a latex having a polymerization rate of 99% and an average particle size of 0.23 μm. Mw of resin particles
Was 3 × 10 ⁵ , and Tg was 38 ° C.

Production Example 4 of Comparative Resin Particles: Resin Particles (L
L-4) Production Example 2 of resin particles (L) except that 20 g of methyl methacrylate and 8 g of 2- (N, N-diethylamino) ethyl acrylate were changed to 28 g of methyl methacrylate in Production Example 2 of resin particles (L). The particles were produced in the same manner as in. The obtained white dispersion was a latex having a polymerization rate of 99% and an average particle size of 0.23 μm. The resin particles had Mw of 3 × 10 ⁵ and Tg of 42 ° C.

Example 1 and Comparative Examples A to B <Preparation of printing plate> 200 g of photoconductive zinc oxide, 2 g of resin (B-1) having the following structure, resin (B-2) having the following structure
18 g, 0.018 g of the cyanine dye (1) having the following structure,
A mixture of 0.15 g of phthalic anhydride and 300 g of toluene was placed in a homogenizer (manufactured by Nippon Seiki Co., Ltd.) to rotate at a rotation speed of 6 ×.
A photosensitive layer-forming composition was prepared by dispersing at 10 ³ rpm for 10 minutes, and the composition was coated on a support for ELP master 2X type (manufactured by Fuji Photo Film Co., Ltd.) so that the dry adhesion amount was 20 g /
As a m ^2, it was coated by a wire bar, 1 at 110 ° C.
A printing original plate was prepared by drying for 0 seconds and then leaving it in the dark at 20 ° C. and 65% RH for 24 hours.

[0128]

[Chemical formula 26]

<Preparation of Liquid Developer (LD-1)> 10 g of a dodecyl methacrylate / acrylic acid (95/5 mass ratio) copolymer, 10 g of alkali blue and 30 g of Isopar H were used together with glass beads in a paint shaker (Toyo Seiki ( Co., Ltd.) and dispersed for 4 hours to obtain a fine blue dispersion of alkali blue.

Production of Resin Particles (L) Resin Particles (L
-1) 6 g (as solid content), 1.0 of the blue dispersion
g (as solid content), hexadecyl alcohol (FO
Liquid developer for electrostatic photography (LD-1) by diluting C-1600, Nissan Chemical Co., Ltd.) 10 g and cobalt naphthenate salt 0.01 g to 1 liter of Isopar G.
Was produced.

<Production of Comparative Developers A and B> In the production of the above liquid developer (LD-1), resin particles (L-
Comparative liquid developers A and B were prepared in the same manner except that 1) was replaced with the following resin particles. Comparative liquid developer A: Resin particles (LL-1) obtained in Production Example 1 of comparative resin particles. Comparative liquid developer B: Resin particles (LL-2) obtained in Production Example 2 of comparative resin particles. The charge characteristics, image reproducibility, printability, etc. of these liquid developers were examined, and the results are shown in Table-F.

[0132]

[Table 8]

The evaluations shown in Table-E were carried out as follows. Note 1) Charging characteristics / AC electric conductivity AC electric conductivity (pS / c)
m) is an LCR meter (Ando Electric Co., Ltd. AG-431)
It was measured using 1). At the time of measurement, an LCR meter was placed in a self-made aluminum shield box containing 2.3 ml of the liquid developer to be measured through a test lead (Ando Electric Co., Ltd. AG-4912). It is connected to a special electrode (LP-05 manufactured by Kawaguchi Electric Co., Ltd., electrode constant 198), conductance is measured at an applied voltage of 5 V and a measurement frequency of 1 kHz, and the value is divided by the electrode constant to be converted into electric conductivity. did. At the time of measurement, the measurement parameter of the LCR meter was set to capacitance, and the circuit mode was set to parallel mode.

Particle Charge Fraction As shown by the following equation, it represents the ratio of the charge amount of dispersed particles in the liquid developer.

[0135]

[Equation 1]

Here, the charge amount of the supernatant was determined by centrifuging the liquid developer (conditions: 1 × 10 ⁴ rpm 2 hours).
Represents the AC electric conductivity of a transparent liquid which is a supernatant obtained by allowing the particles to settle.

Conditions I and II indicate that the aging state after the liquid developer is manufactured is changed. Condition I is that the liquid developer obtained by mixing all the components is subjected to normal temperature and normal humidity ( 25 ° C,
65% RH) aged for 1 week (fresh product)
On the other hand, the condition II is to store the fresh product under conditions of high temperature and high humidity (35 ° C., 85% RH) for 2 months,
It is a product that has been forcibly aged (aged product).

Note 2) Image reproducibility The above printing original plate was charged at -6 kV and 2.8 as a light source.
A mW-output gallium-aluminum-arsenic semiconductor laser (oscillation wavelength 780 nm) was used to irradiate 6.4 μjoul / cm ² on the surface of the printing original plate, exposed at a pitch of 25 μm and a scanning speed of 300 m / sec, and then a liquid developer. Is developed using each of the liquid developers described above, and Isopar G (Esso Chemical Co., Ltd.), which is an isoparaffinic solvent, is used.
After rinsing with a rinsing solution (1), the image was formed by fixing at a plate surface temperature of 70 ° C. for 10 seconds. Fogging, image quality of the image and the like of the obtained plate-making image were visually evaluated. Note 3) Printability The original plate on which an image was formed according to the method of image reproducibility described above was used as a desensitizing solution ELP-E2 (Fuji Photo Film Co., Ltd.).
(Manufactured by K.K.) was used to make a printing plate by passing through an etching machine once. The printing plate thus obtained was printed using a solution of ELP-E2 (manufactured by Fuji Photo Film Co., Ltd.) diluted 20 times with water as fountain solution, and neutral paper as the base paper for printing. Printing was performed by using a Hamada Star 800SX type (manufactured by Hamada Star Co., Ltd.) as a machine, and the quality of the printed matter of the 10th printed sheet and the number of printed sheets in which there was no omission in the image portion of the printed matter were examined. As shown in Table-E, the charge characteristics of the liquid developer of the present invention were extremely stable even when stored under severe conditions with almost no change in the total charge amount and the particle charge fraction. . On the other hand, in Comparative Example A, the change amount of the total charge amount with time was relatively small, but the change of the charge fraction of the particles was large. In Comparative Example B, the total charge amount and the particle charge fraction were low, and further decreased with time. When an image was actually formed, the liquid development of the present invention was good under both conditions I and II. In Comparative Example A, the occurrence of background fog was observed under Condition II, and in Comparative Example B, image smearing occurred on the entire surface. When printed as a printing plate, when the liquid developer of the present invention was used, clear printed matter of 10,000 sheets or more was obtained even under the condition II.
On the other hand, Comparative Examples A and B could not be put to practical use as printed matter after printing.

Example 2 and Comparative Examples C to D <Preparation of liquid developer (LD-2)> Tetradecyl methacrylate / methacrylic acid (95/5 mass ratio) copolymer 1
0g, Nigrosine 10g and Isopar G 30g together with glass beads Paint shaker (Toyo Seiki Co., Ltd.)
Manufactured) and dispersed for 6 hours to obtain a fine dispersion of nigrosine. 6 g of resin particles (L-2) (as solid content),
1 g of the above nigrosine dispersion (as solid content), vinyl acetate / semi-maleic acid tetradecylamide copolymer 0.0
1 g and branched octadecyl alcohol (FOC-180
0, manufactured by Nissan Kagaku Co., Ltd., and diluted with 1 liter of Isopar G to obtain a liquid developer for electrostatic photography (LD-).
2) was produced. <Production of Comparative Developers C and D> The liquid developer (LD
-2), except that the resin particles (L-2) are replaced with the following resin particles, the liquid developer C for comparison is similarly used.
And D were made. Comparative liquid developer C: Resin particles (LL-3) obtained in Production Example 3 of comparative resin particles. Comparative liquid developer D: Resin particles (LL-4) obtained in Production Example 4 of comparative resin particles.

The above liquid developer was applied to a fully automatic plate-making machine ELP58.
ELP, which is an electrophotographic light-sensitive material, is used as a developer of 0RX (manufactured by Fuji Photo Film Co., Ltd.) and a desensitizing solution ELP-PEX (manufactured by Fuji Photo Film Co., Ltd.) is used.
A master 2X type (manufactured by Fuji Photo Film Co., Ltd.) was exposed, developed and desensitized. Blackening rate (image area)
A 35% original was used. The plate making speed was 6 plates / minute. After processing 10,000 sheets of the ELP master 2X type, the presence or absence of toner adhesion stains on the developing device was observed. The results are shown in Table-G.

[0141]

[Table 9]

A plate made using the liquid developer of the present invention,
Even after 10,000 plates, the developing device did not become dirty. Comparative Example C
In D and D, stains on the developing device due to adhesion of toner dust were observed. Further, printing was carried out by a conventional method using the 10,000th printing plate for offset obtained by plate-making, and the number of printed sheets until the occurrence of character loss in the image of the printed matter, scraping of the solid portion, etc. was examined. The printing plate obtained using the developer of the present invention was good even at 10,000 sheets or more. On the other hand, in Comparative Examples C and D, image defects and the like of the printed matter occurred after printing. Further, a developer (LD-2) aged under the condition II of the example (stored under 35 ° C./85% RH for 2 months) was subjected to the same test as above, and the performance was almost the same as that of the fresh product. showed that. From the above results, it is understood that the liquid developer of the present invention does not stain the developing device at all, and at the same time, the printing plate obtained has excellent printing durability.

Example 3 <Preparation of printing original plate> The following photoconductive layer coating solution was applied on a grained and positively oxidized aluminum plate with a bar coater and dried at 120 ° C. for 10 minutes to form a film. Thickness 3.
An original plate for printing of 0 μm was prepared.

X-type metal-free phthalocyanine 20 parts Copolymer of butyl methacrylate and methacrylic acid (methacrylic acid 35 mol%) 140 parts 1-methoxy-2-propanol 555 parts Methyl ethyl ketone 555 parts A mixture having the above composition was added at a high speed. It was dispersed for 2 hours with a dispersion mixer Dynamill (KDL-5, manufactured by WABACHOFEN) to obtain a coating liquid for a photoconductive layer.

<Preparation of Liquid Developer (LD-3)> 9 g (as solid content) of resin particles (L-1) of Production Example 1 of resin particles (L), tetradecyl alcohol (FOC140).
0) 10 g and 0.011 g of zirconium naphthenate
Was prepared with Isopar H to a volume of 1 liter to prepare a liquid developer (LD-3). When the charging characteristics were measured by the same method as described in Example 1, the results shown in Table H below were obtained.

[0146]

[Table 10]

Even after the passage of time under severe conditions, it showed a charge characteristic almost equivalent to that of the fresh product and extremely stable.

The printing plate having the above photoconductive layer was subjected to corona discharge so that the surface of the photoconductive layer was uniformly charged to +400 V, and then 3 μjoul / cm ² on the surface using a semiconductor laser (light source wavelength 780 nm). Under irradiation, pitch 25μ
m and a scanning speed of 300 m / sec.
Subsequently, the liquid developer (LD-3) of the present invention was used to perform reversal development under the condition of a bias voltage of +180 V, and then the image was fixed by heating at a temperature of 120 ° C. for 1 minute. 40 parts of potassium silicate, 10 parts of potassium hydroxide, 20 parts of benzyl alcohol, and 20 parts of ethanol were mixed with 900 parts of water.
A non-image area was removed by immersing in a diluted etching solution for 10 seconds, washed sufficiently with water and dried to prepare a printing plate. When this printing plate was visually evaluated with a magnifying glass of 60 times (manufactured by PEAK Co., Ltd.), no fine lines or fine characters in the image area were observed and the image was extremely clear. Next, this printing plate
After gumming treatment, offset printing machine (Oliver 52
The pattern was printed on Sakurai Seisakusho Co., Ltd. Even after printing 100,000 sheets or more, the image quality of the printed matter was clear and no background fog was observed. Further, when the liquid developer under the condition II was used to carry out plate making, etching treatment and printing in the same manner as described above, the same result as that of the fresh product was obtained.

Further, the printing plate precursor was made into a 5000 plate, and the stains on the developing portion were examined. No stain such as adhesion of toner dust was found, and the liquid developer had very good redispersibility. showed that. In addition, when the image on the printing plate after the 5000th plate was etched was visually evaluated, fine lines and fine characters were clear and no difference was seen from the printing plate of the first plate. As described above, the liquid developer of the present invention shows stable charging characteristics even when aged under severe conditions in an electrophotographic plate making system in which a non-image area is eluted to form a printing plate, and has excellent dispersibility. , Showed redispersibility. Further, the printing durability was also satisfactory.

Examples 4 to 19 Each liquid was prepared in the same manner as in Example 1 except that the resin particles shown in Table I below were used in place of the resin particles (L-1) in Example 1. A developer was prepared. The AC electric conductivity of the obtained developer was 95 to 100 (pS / cm), and the charge fraction of the particles was 90 to 95%. Also, in the case of condition II, almost no change occurred.

[0151]

[Table 11]

Each of the obtained liquid developers was used in an electrophotographic plate making system in the same manner as in Example 1, and its performance was examined. Each liquid developer exhibits the same performance as in Example 1,
The image reproducibility, dispersibility, and printability were good. Also,
Under the condition II, all the developers exhibited the same performance and were good.

Examples 20 to 28 In the same manner as in Example 2, except that the resin particles shown in Table J below were used in place of the resin particles (L-2) in Example 2, each liquid was prepared. A developer was prepared.

[0154]

[Table 12]

Each of the obtained liquid developers was used in an electrophotographic plate making system in the same manner as in Example 2 and its performance was examined. Each liquid developer exhibits the same performance as in Example 2,
The image reproducibility, dispersibility, and printability were good. Further, the developing device did not stain as in the second embodiment. Further, each developer exhibited the same performance even under the condition II and was good.

Example 29 A photosensitive drum made of amorphous silicon was rotated at a peripheral speed of 10 mm / sec, and the following dispersion liquid was supplied to the surface of the photosensitive member by using a slit electrodeposition apparatus while the photosensitive member side was grounded and slit electric charge was applied. A voltage of +200 V was applied to the electrode side of the deposition device to electrodeposit the resin particles. Then, the dispersion liquid was removed by air squeeze and the film was melted and filmed by an infrared line heater to form a thermoplastic resin transfer layer having a film thickness of 1.5 μm on the photoconductor. <Transfer Layer Forming Dispersion> Dispersion stabilizing resin [octadecyl methacrylate / acrylamide (97/3 mass ratio) copolymer, mass average molecular weight: 4 × 10 ⁴ ] 12 g, vinyl acetate 96 g, tetradecyl methacrylate 4 g and Isopar H384 g The mixed solution of was heated to 70 ° C. while stirring under a nitrogen stream. 2,2′-azobis (isovaleronitrile) (abbreviation AIVN) as a polymerization initiator
0.8 g was added and reacted for 3 hours. Twenty minutes after the addition of the initiator, white turbidity occurred and the reaction temperature rose to 88 ° C. Further, 0.5 g of the above initiator was added and reacted for 2 hours, then the temperature was raised to 100 ° C. and stirred for 2 hours to distill off unreacted vinyl acetate. After cooling, pass through a 200-mesh nylon cloth to give a white dispersion (polymerization rate 90%, average particle size 0.21
μm) was obtained. 10 g of the thermoplastic resin dispersion (as a solid content) and 0.001 g of zirconium naphthenate were added to 1 liter of Isopar H to prepare a positively charged resin particle dispersion liquid. An electrophotographic process was immediately performed while maintaining the surface temperature of the photoconductor at 40 ° C. First, after corona charging this photoreceptor to + 700V in the dark, read it from the original document in advance and expose it with 780 nm light using a semiconductor laser based on the information stored in the hard disk in the system as digital image data. did. The potential of the exposed portion was + 220V and that of the unexposed portion was + 660V. Then, after pre-bathing with Isopar H by a pre-bath device incorporated in the developing unit, the following positively charged liquid developer of the present invention was supplied from the developing unit to the surface of the photoreceptor. At this time, a developing bias voltage of +500 V was applied to the developing unit side to carry out reversal development so that the toner was electrodeposited on the unexposed portion. Then, rinsed in a bath of Isopar H alone to remove stains on the non-image area, the liquid was drained by an air squeeze, passed through an infrared line heater and dried. <Preparation of liquid developer (LD-4)> Blue pigment (Lionol Bl
ue FG-7350, manufactured by Toyo Ink Co., Ltd./Octadecyl methacrylate-methyl methacrylate (7/3 mass ratio) 4 g of Isopar G dispersion (as solid content) consisting of 1/1 mass ratio of block copolymer, resin particles (L-20) 8g
(As solid content) and octadecyl vinyl ether-
A liquid developer (LD-4) was prepared by diluting 0.01 g of a maleic acid dodecylamide copolymer with 1 L of Isopar G. Next, after passing under an infrared line heater to measure the surface temperature with a radiation thermometer and preheating to about 80 ° C., the coated paper is superposed on the photoreceptor having a transfer layer, and 10 kgf / cm ² (980kP
15mm / s under the heating rubber roller whose surface temperature is controlled to 120 ℃ under the pressure of a).
It was passed at a speed of ec. After that, after passing the bottom of the cooling roller to cool and peeling off the coated paper,
The toner on the photoconductor was transferred to the coated paper side together with the transfer layer, and a color image was obtained. The color image obtained was extremely clear and no fog was observed in the non-image area. Also, when the liquid developer (CD-4) was forcibly aged as in Example 1 (Condition II), no difference was seen between the fresh product and the product was clear.

[0157]

INDUSTRIAL APPLICABILITY The liquid developer of the present invention accelerates the developing-fixing process by using specific resin particles, and stabilizes the charge of particles even in an electrophotographic plate making system using a large plate master plate. It is possible to provide an offset printing plate having excellent properties, dispersion stability, redispersibility, and fixability, and having excellent printing ink oil sensitivity and printing durability.

Claims (2)

[Claims] 1. A liquid developer for electrostatic photography comprising at least resin particles dispersed in a non-aqueous solvent having an electric resistance of 10 ⁹ Ωcm or more and a dielectric constant of 3.5 or less, wherein the dispersed resin particles are A monomer (A containing at least one monofunctional monomer (A) which is soluble in a non-aqueous solvent and becomes insoluble by polymerization, and an amino group represented by the general formula (I). ) and at least one copolymerizable monofunctional monomer (B), -PO ₃ H ₂ group, -SO ₃ H group and -SO ₂ H
At least one monofunctional monomer (C) copolymerizable with the monomer (A), containing at least one acidic group selected from the group, and having a substituent containing a fluorine atom and / or a silicon atom. , At least one monofunctional monomer (D) copolymerizable with the monomer (A), and the following general formula (PI)
Copolymer resin particles obtained by polymerizing and granulating in the presence of at least one dispersion stabilizing resin (P), which comprises at least a polymerization component represented by, and is dispersed colloidally in the non-aqueous solvent. A liquid developer for electrostatic photography, characterized by being present. [Chemical 1] In formula (I), R ¹ and R ² may be the same or different and each represents a hydrogen atom or a hydrocarbon group having 1 to 22 carbon atoms, or R ¹ and R ² are bonded to each other to form a ring together with a nitrogen atom. May be formed. [Chemical 2] In general formula (PI), V ⁰ is -COO-, -OCO-,-.
_{(CH 2) r COO -,} - (CH 2) r OCO -, - O- or ## STR3 ## (Where X is a direct bond, -O-, -OCO- or -CO
Represents O-). r represents an integer of 1 to 12. L
Is an alkyl group having 8 to 32 carbon atoms or 8 to 32 carbon atoms
Represents an alkenyl group. b ¹ and b ² may be the same as or different from each other and each represents a hydrogen atom, a halogen atom, a cyano group, a hydrocarbon group, —COO-D ¹ , or —COO-D ¹ via a hydrocarbon group ( Here, D ¹ represents a hydrogen atom or an optionally substituted hydrocarbon group). 2. The dispersion stabilizing resin (P) has the general formula (P
The electrostatic block according to claim 1, which is a block copolymer comprising a block containing at least a polymerization component represented by I) and a block containing no polymerization component represented by the general formula (PI). Liquid developer for photography.