JP2001098198A - Oily ink for electrostatic type ink jet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an oily ink which is used for electrostatic type ink jets, has excellent ink extrusion stability and excellent brilliant image-forming property, gives images having excellent strengths, and enables the formation of printing plates that can form many printed products having brilliant images. SOLUTION: This oily ink for electrostatic ink jet is obtained by dispersing copolymer resin particles in a non-aqueous carrier liquid having an electric resistance of >=109 Ω.cm and a dielectric constant of <=3.5. The copolymer resin particles are obtained by subjecting a solution containing (A) a monofunctional monomer which is soluble in non-aqueous solvents but can be polymerized into a polymer insoluble in the solvents, (B) a monofunctional monomer which contains an amino group and can be copolymerized with the monomer (A), (C) a monofunctional monomer which contains a SO3H group and/or a SO2H group and can be copolymerized with the monomer (A), and (P) a dispersion-stabilizing resin whose main chain is partially cross-linked and is soluble in the non-aqueous solvents, to a copolymerizing and particularizing treatment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil-based ink for an electrostatic ink jet used for forming an image by an electrostatic (electrostatic attraction or electrostatic attraction) ink jet recording system.

[0002]

2. Description of the Related Art Ink jet recording is a recording method capable of high-speed printing with low noise, and is a recording method that has been rapidly spreading recently. Ink jet recording is a method in which a liquid ink having a high fluidity is ejected from fine nozzles and is recorded on recording paper, and there are an on-demand (optional ejection) and a continuous (continuous ejection) method. Further, a recording method called an electrostatic method (Sweet type or Hertz type) is known as a continuous type, and a piezo piezoelectric method, a thermal inkjet method, or an electrostatic acceleration type is known as an on-demand type.

As an on-demand type ink jet system using electrostatic force, Susumu Ichinose, Yuji Ohba, IEICE Transactions vol.J66-C (No.1), p47 (1983), Tadayoshi Ohno, Mamoru Mizuguchi, The Institute of Image Electronics Engineers of Japan Magazine vol. 10, (No. 3), p157 (1981), etc., a method called an electrostatic acceleration type ink jet or a slit jet is known.Specific embodiments are, for example, JP-A-56-170, No. 56-4467, No. 5
No. 7,151,374. This involves supplying ink to a slit-shaped ink chamber in which a large number of electrodes are arranged on the inner surface of a slit-shaped ink holding unit from an ink tank, and selectively applying a high voltage to these electrodes to form a slit-shaped ink chamber. Ink is recorded by ejecting ink near the electrodes onto the recording paper that is in close proximity.

As another system which does not use a slit-shaped recording head, Japanese Patent Application Laid-Open No. 61-2111048 discloses a method in which ink is filled in a hole of a film-shaped ink support having a plurality of minute holes and a multi-needle is provided. There is disclosed means for selectively applying a voltage by an electrode to move ink in a hole to recording paper.

[0005] The principle of the flight of these inks is that a high voltage applied to the arranged electrodes causes electric charges to be injected into the ink in contact with the electrodes, and the ink near the electrodes to be charged, thereby generating an electrostatic force. It is interpreted that ink is ejected. Therefore, the ink is not normally charged, and only when a voltage is applied, the ink near the electrodes is charged by energization to obtain a discharging force. Inks used in these methods have an electric resistance of about 10 ⁶ to 10 ⁸ Ω · cm. Since water has a low electric resistance, a material in which a colorant composed of a dye is dispersed in an oily solvent with a dispersing aid such as a surfactant to adjust the electric resistance is generally used.

Further, a method of controlling the viscosity and specific resistance of the oil-based ink used (Japanese Patent Publication No. 52-13127).
), A method of controlling the relative permittivity of the dispersion medium used for the ink and the specific resistance of the ink (JP-A-53-29808), changing the type of the dispersion medium of the oil-based ink, or using a specific compound as the ink composition. Method for containing (JP-A-3-79
677, JP-A-3-64377, JP-A-4-202
386, JP-A-7-109431) and the like. However, these prior arts are not suitable for the storage stability of oil-based ink, the reproducibility of recorded images after repeated use, the bleeding resistance of the ink on the ink receiving material, the clogging resistance in the nozzle and the ink supply path, and the ink. Discharge stability and the like are not yet sufficiently satisfactory, and further improvement in performance is desired.

On the other hand, another electrostatic ink jet technology is
It is disclosed in WO93 / 11866. In this method, an insulating liquid is supplied to an ink ejection device with ink in which charged particles or particles exhibiting chargeability under an electric field are dispersed, and an ink meniscus is formed at an ejection electrode tip for ejecting the ink. It has a series of steps of forming an electric field between a counter electrode on which a recording medium is mounted and an ejection electrode to fly aggregated particles by electrophoresis and concentrating the particle concentration in the ink meniscus. I have.

[0008] Unlike the conventional method, the feature of this method that does not require an ink nozzle structure is that an ink containing dispersed particles such as a pigment can be ejected in a fine droplet size of about several μm. It is possible to change the dot size of an image by changing the droplet size by controlling the ejection signal, and the like. Accordingly, it is possible to draw an image based on the light- and water-resistant pigment and form a clear image of a continuous halftone image at high resolution and high density.

The oily ink used has an electric resistance value of 1
0 ⁹ Ω · cm while more insulating liquid and chargeable particles insoluble ones of the content containing the charge agent WO95 / 140
No. 4, WO 96/10058. Further, those in which the charge amount of charged particles or the average particle size of the particles is specified (Japanese Patent Application Laid-Open Nos. 9-193389 and 8-291)
No. 267) or those in which the thermophysical properties of a dried ink composition are specified (Japanese Patent Application Laid-Open No. 9-137094).

However, when ink-jet recording is performed using these oil-based inks, instability of ink ejection or insufficient concentration of pigment particles in the ink occurs, resulting in lack of formed images and blurring of images. Or an insufficient image density (particularly, a solid image portion). In addition, when the ink that has been stored for a long time is used, the ejection conditions (applied voltage, etc.) vary with the case of using fresh ink, and the ratio of concentrated and ejected ink changes significantly. In such a case, a problem such as change occurs.

On the other hand, with the recent development of office equipment and the progress of OA, in the field of light printing, lithographic printing plate precursors having an image receiving layer on a water-resistant support are subjected to plate making, that is, image formation by various methods. A plate making method for creating an offset printing plate has become widespread, and as one of the plate making methods, plate making is performed by an ink jet method. When a printing plate on which a clear image is formed using conventional oil-based ink is actually printed, the number of prints that can obtain a clear print without losing an image portion is limited to several hundreds at most. It was enough. That is, the offset printing has a problem that the fixing strength of an image composed of ink particles is insufficient.

[0012]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an oil-based ink for electrostatic ink jet which is excellent in ink ejection stability, clear image forming property and image strength. Another object of the present invention is to provide an oil-based ink for an electrostatic inkjet that can form a printing plate capable of printing a large number of printed images with clear images. Another object of the present invention is to provide an oil-based ink for electrostatic ink jet which is excellent in redispersibility and storage stability of dispersed particles, does not become clogged in an ink supply path, and can stably eject ink.

[0013]

It has been found that the above-mentioned object is achieved by the following constitutions.

(1) An oil-based ink for electrostatic ink-jet printing, comprising at least charged resin particles dispersed in a non-aqueous carrier liquid having an electric resistance of 10 ⁹ Ω · cm or more and a dielectric constant of 3.5 or less. The resin particles are soluble in a non-aqueous solvent and contain at least one monofunctional monomer (A) which becomes insoluble by polymerization, and an amino group represented by the general formula (I), at least one monomer (a) copolymerizable with the monofunctional monomer (B), containing a -SO ₃ H group and / or -SO ₂ H group, copolymerized with the monomer (a) A polymer containing at least one of the possible monofunctional monomers (C) and a component represented by the following general formula (II), wherein a part of the main chain of the polymer is crosslinked, Contains at least one dispersion stabilizing resin (P) soluble in non-aqueous solvents That the solution electrostatic inkjet oil green ink, which is a copolymer resin particles obtained by the polymerizing granulation.

[0015]

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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 bonded to each other. A ring may be formed together with the nitrogen atom.

[0017]

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In the general formula (II), V ⁰ is -COO-, -O
_{CO -, - (CH 2)} r COO -, - (CH 2) r OCO-,
-O- or

[0019]

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(Where X is a mere bond, -O-, -OC
O- or -COO-). r represents an integer of 1 to 12. L represents an alkyl group having 8 to 32 carbon atoms or an alkenyl group having 8 to 32 carbon atoms. b ¹ and b ² may be the same or different, each represents a hydrogen atom, a halogen atom, a cyano group, a hydrocarbon group having 1 to 7 carbon atoms, -C
OO-D ¹ or —COO-D ¹ via a hydrocarbon group
(Where D ¹ represents a hydrogen atom or a hydrocarbon group having 1 to 22 carbon atoms).

(2) A dispersion stabilizing resin (P) is provided at one end of at least one polymer main chain with -PO ₃ H ₂ , -SO
_{3 H, -COOH, -P (=} O) (OH) R 11 [wherein R ¹¹ represents a hydrocarbon group or -OR ^12, (R ¹² represents a hydrocarbon group)], -OH, a formyl group , -CONR ¹³
R ¹⁴ , —SO ₂ R ¹³ R ¹⁴ (where R ¹³ and R ¹⁴ may be the same or different and each represent a hydrogen atom or a hydrocarbon group), a cyclic acid anhydride-containing group, and an amino group The oil-based ink for electrostatic ink jet according to the above (1), which contains at least one polar group.

(3) A dispersion stabilizing resin (P) is attached to one end of at least one polymer main chain by the following general formula (III):
The electrostatic oil-based ink for electrostatic inkjet recording according to the above (1), wherein the oil-based ink is formed by bonding a polymerizable double bond group represented by the following formula:

[0023]

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In the general formula (III), V ¹ is -COO-, -O
_{CO -, - (CH 2)} t COO -, - (CH 2) t OCO-,
_{-O -, - SO 2 -,} - CONHCOO -, - CONH
^{CONH -, - CON (D 2} ) -, - SON (D 2) - or a phenylene group (wherein D ² represents a hydrogen atom or a hydrocarbon group having 1 to 22 carbon atoms, t is 1 to 4 Indicates an integer). c ¹ and c ² may be the same or different from each other, and have the same meanings as b ¹ and b ² in the formula (III).

(4) The dispersed resin particles further contain at least one monofunctional monomer (D) represented by the following general formula (IV) copolymerizable with the monomer (A). The oil ink for electrostatic inkjet according to any one of the above (1) to (3), which is a copolymer resin particle obtained by polymerizing and granulating a solution.

[0026]

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In the general formula (IV), U¹Is -COO-, -C
ONH-, -CON (E^Two)-(Where E^TwoIs an aliphatic group
Or a substituent represented by the following general formula (IVa)),
-OCO-, -CONHCOO-, -CH_TwoCOO-,
− (CH_Two)_SOCO-, wherein s is an integer of 1 to 4
), -O- or -C₆H_FourRepresents -COO-. c¹
And c^TwoAre the same or different and each represents a hydrogen atom,
Alkyl group, halogen atom, cyano group, -COO-E^ThreeMa
Or -CH_TwoCOO-E^Three(Where E^ThreeRepresents an aliphatic group
Represents). E¹Is an aliphatic group with 8 or more carbon atoms or
8 or more (but directly bonded to carbon atom and nitrogen atom
A hydrogen atom is excluded) represented by the following general formula (IVa)
Represents a group. General formula (IVa)-(A¹-B¹)_m-(A^Two-B^Two)_n-R^{twenty one} In the general formula (IVa), R^{twenty one}Is a hydrogen atom or a carbon number of 1 to 1
8 represents an aliphatic group. B¹And B^TwoAre the same or different
Thus, -O-, -S-, -CO-, -CO _Two−, −
OCO-, -SO_Two-, -N (R^{twenty two})-, -CON (R
^{twenty two})-, -N (R^{twenty two}) CO-, -N (R^{twenty two}) SO_Two−,
-SO_TwoN (R^{twenty two})-, -NHCO_Two-Or -NHCO
NH- (where R^{twenty two}Is the above R^{twenty one}Synonymous with
). A¹And A^TwoAre the same or different,
A group represented by the formula (IVb) and a hydrocarbon having 1 to 18 carbon atoms:
Represents at least one group selected from groups. m
And n are the same or different and each represents an integer of 0 to 4
Represent. However, the sum of m and n does not become zero.

[0028]

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In the general formula (IVb), B ³ and B ⁴ are the same or different and have the same meaning as B ¹ and B ² above, A ⁴ represents a hydrocarbon group having 1 to 18 carbon atoms, and R ²³ It has the same meaning as above R ^21. p represents an integer of 0 to 4.

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The oil-based ink of the present invention will be described below. The non-aqueous carrier liquid having an electric resistance of 10 ⁹ Ω · cm or more and a dielectric constant of 3.5 or less used in the present invention is preferably a linear or branched aliphatic hydrocarbon, alicyclic hydrocarbon, or aromatic hydrocarbon. Examples include hydrogen, halogen-substituted products of these hydrocarbons, and silicone solvents such as silicone liquid and silicone oil.

For example, examples of the hydrocarbon solvent 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 (Isoper; trade name of Exxon), Shellsol 70,
Shellsol 71 (Shellsol; trade name of Shell Oil), Amsco OMS, Amsco 460 solvent (Amsco; trade name of Spirits) and the like.

As the halogen-substituted hydrocarbon solvent, there is a fluorocarbon solvent. For example, perfluoroalkanes represented by C _n F _{2n + 2} such as C ₇ F ₁₆ and C ₈ F ₁₈ (“Fluorinert” manufactured by Sumitomo 3M) PF5080 "," Florinert PF5070 "(trade name), fluorinated inert liquid (" Fluorinert FC series "(trade name) manufactured by Sumitomo 3M), fluorocarbons (" Crytox GPL series manufactured by DuPont Japan Limited ") "(Trade name) etc.), CFCs (" HCF "manufactured by Daikin Industries, Ltd.)
C-141b ”(trade name), [F (CF ₂ ) ₄ CH ₂ C
Iodinated fluorocarbons such as [H ₂ I] and [F (CF ₂ ) ₆ I] (“I-14 manufactured by Daikin Fine Chemical Laboratory)
20 "," I-1600 "(product name) and the like.

As the silicone solvent for the silicone liquid and silicone oil, dialkylpolysiloxanes (for example, hexamethyldisiloxane, tetramethyldisiloxane, octamethyltrisiloxane, hexamethyltrisiloxane, heptamethyltrisiloxane, decamethyltetrasiloxane, Trifluoropropyl heptamethyltrisiloxane, diethyltetramethyldisiloxane, etc.), cyclic dialkylpolysiloxane (for example, hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane,
Examples thereof include tetra (trifluoropropyl) tetramethylcyclotetrasiloxane and the like, methylphenyl silicone oil (for example, KF56, KF58 (trade name, manufactured by Shin-Etsu Silicon Co., Ltd.)) 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 carrier liquid is preferably about 10 ¹⁶ Ω · cm, and the lower limit of the dielectric constant is preferably about 1.80.

The non-aqueous dispersed resin particles (hereinafter sometimes referred to as dispersed resin particles or latex particles), which are the most important constituents in the oil-based ink of the present invention, contain specific components (formula (II)) in a non-aqueous solvent. )) And in the presence of a dispersion-stabilizing resin (P) having a crosslinked structure, a monofunctional monomer containing at least one monofunctional monomer (A) and an amino group represented by the general formula (I) at least one kind and -SO ₃ H groups and / or one containing -SO ₂ H group functionality monomers at least one of (C) polymerized granulated sex monomer (B).

Here, as the non-aqueous solvent, basically,
Any ink that can be mixed with the non-aqueous carrier liquid of the oil-based ink can be used.

That is, the solvent used for producing the dispersed resin particles may be any solvent that is miscible with the carrier liquid, and is preferably a linear or branched aliphatic hydrocarbon, an alicyclic hydrocarbon, or an aromatic hydrocarbon. Group hydrocarbons and their halogen-substituted products. For example, octane, isooctane, decane, isodecane, decalin, nonane,
Dodecane, isododecane, isoper E, isoper G, isoper H, isoper L, shelsol 70,
Shellsol 71, AMSCO OMS, AMSCO 460 solvent and the like are used alone or in combination.

Organic solvents which can be used in combination with these non-aqueous solvents include alcohols (for example, ethyl alcohol, propyl alcohol, butyl alcohol, and the like).
Ethylene glycol monomethyl ether, fluorinated alcohols, etc., ketones (eg, methyl ethyl ketone, acetophenone, cyclohexanone, etc.), carboxylic 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 and the like).

It is desirable that the organic solvent used by mixing these is distilled off under heating or under reduced pressure after the polymerization granulation. However, even if the organic solvent is brought into the oil-based ink as a latex particle dispersion, the resistance of the ink is reduced. There is no problem as long as the conditions satisfy the condition of 10 ⁹ Ω · cm or more and the dielectric constant of 3.5 or less.

In general, it is preferable to use the same solvent as the carrier liquid at the stage of preparing the resin dispersion. As described above, a linear or branched aliphatic hydrocarbon, an alicyclic hydrocarbon,
Examples include aromatic hydrocarbons and halogenated hydrocarbons.

The monofunctional monomer (A) in the present invention comprises:
Any monofunctional monomer that is soluble in a nonaqueous solvent but insolubilized by polymerization may be used. Specifically, for example, a monomer represented by the following general formula (V) can be mentioned.

[0042]

[Formula 13]

In the general formula (V), V ² represents —COO—, —O
_{CO -, - CH 2 OCO -} , - CH 2 COO -, - O-,
-CONHCOO-, -CONHOCO-, -SO
^{_{2 -, - CON (G 1}} ) -, - SO 2 N (G 1) -., Or a phenylene group (hereinafter sometimes to be referred to as a phenylene group and "-Ph-" Incidentally, phenylene group 1,2 −,
Includes 1,3- and 1,4-phenylene groups. ). Here, G ¹ is a hydrogen atom or an optionally substituted aliphatic group having 1 to 8 carbon atoms (for example, a methyl group, an ethyl group, a propyl group, a butyl group, a 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-methoxyethyl group, 3-methoxypropyl group, etc.).

W is a hydrogen atom or an optionally substituted aliphatic group having 1 to 6 carbon atoms (for example, methyl, ethyl, propyl, butyl, 2-chloroethyl, 2,2-dichloroethyl, 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.).

D ¹ and d ² may be the same or different from each other, and are preferably a hydrogen atom, a halogen atom (eg, a chlorine atom, a bromine atom, etc.), a cyano group, and a carbon number of 1 to 3.
Alkyl group (e.g. methyl group, ethyl group, propyl group, etc.), - COO-G ² or -CH ^₂ -COO-G ₂ [wherein G ² is 1 hydrogen atom or a carbon atoms which may be substituted,
And 0 or less hydrocarbon groups (for example, representing an alkyl group, an alkenyl group, an aralkyl group, an aryl group, etc.).

Specific monofunctional monomers (A) include:
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.); unsaturated acids such as acrylic acid, methacrylic acid, crotonic acid, itaconic acid, and maleic acid Alkyl esters or amides of carboxylic acid having 1 to 4 carbon atoms which may be substituted. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a 2-chloroethyl group, a 2-bromoethyl group and a 2-hydroxy 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-carboxyamidoethyl group, etc .;

Styrene derivatives (for example, styrene, vinyltoluene, α-methylstyrene, vinylnaphthalene,
Chlorostyrene, dichlorostyrene, bromostyrene,
Vinylbenzenecarboxylic acid, chloromethylstyrene, hydroxymethylstyrene, methoxymethylstyrene, vinylbenzenecarboxamide, vinylbenzenesulfonamide, etc.); acrylic acid, methacrylic acid, crotonic acid,
Unsaturated carboxylic acids such as maleic acid and itaconic acid; cyclic acid anhydrides such as maleic acid and itaconic acid; acrylonitrile; methacrylonitrile; a heterocyclic compound containing a polymerizable double bond group (specifically, for example, a polymer Academic Society, "Polymer Data Handbook -Basic Edition-", p.175-184,
Compounds described in Baifukan (1986), for example, N-
Vinylpyridine, N-vinylimidazole, N-vinylpyrrolidone, vinylthiophene, vinyltetrahydrofuran, vinyloxazoline, vinylthiazole, N-vinylmorpholine and the like.

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

Next, the monofunctional monomer (B) used in the present invention will be described. The monofunctional monomer (B) is a monomer containing an amino group represented by the general formula (I) and copolymerizable with the monomer (A). In the monofunctional monomer (B), the polymerizable double bond 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 atom having 1 to 2 carbon atoms.
2 optionally substituted alkyl groups (for example, methyl group,
Ethyl group, propyl group, butyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, dodecyl group,
Tridecyl, tetradecyl, hexadecyl, octadecyl, eicosyl, docosyl, 2-chloroethyl, 2-bromoethyl, 2-cyanoethyl, 2
-Methoxycarbonylethyl group, 2-methoxyethyl group, 3-bromopropyl group and the like, and an optionally substituted alkenyl group having 4 to 18 carbon atoms (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.),

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

R ¹ and R ² may combine with each other to form a ring together with a nitrogen atom, and specifically may contain a hetero atom (for example, an oxygen atom, a nitrogen atom, a sulfur atom, etc.). Represents a ring-forming organic residue. Examples of the formed cyclic amino group include a morpholino group, a piperidino group, a pyridyl group, an imidazolyl group, and a quinolyl group. A plurality of these 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 have an electric detection property, the charge amount of the particles increases, and environmental conditions (low temperature / low humidity to low (High temperature / high humidity) or long-term storage greatly reduces the change in charging characteristics. As a result,
The formed image has a stable image quality. The monomer (B) is preferably used in an amount of 1 to 45% by mass, more preferably 5 to 30% by mass, based on the total amount of the monomer (A).

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

[0054]

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Next, the monofunctional monomer (C) used in the present invention will be described. The monofunctional monomer (C) is-
It is a monomer containing an acidic group selected from SO ₃ H group and —SO ₂ H group and copolymerizable with the monomer (A). The monomer (C) may contain a plurality of the above acidic groups in the molecule. The monomer (C) complements the effect of the monomer (B), further improves the charge characteristics of the resin particles, and acts to always provide a stable and excellent image. The monomer (C) is preferably used in a molar ratio of monomer (B) / monomer (C) of preferably 0.1%.
It is used in the range of 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.

[0057]

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[0058]

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Next, the dispersion stabilizing resin (P) used in the present invention will be described. In the oil-based ink of the present invention, the dispersion stabilizing resin (P) used for forming a stable resin dispersion from a solvent-insoluble polymer formed by polymerizing a monomer in a non-aqueous solvent is the general resin described above. It is a polymer containing at least one repeating unit represented by the formula (II) and soluble in a non-aqueous solvent in which a part of the polymer main chain is crosslinked. The component represented by the general formula (II) is a component that is soluble in the dispersion medium used in the oil-based ink.

In the formula (II), V ⁰ is preferably-
COO -, - OCO -, - CH 2 COO -, - CH 2 OC
O- or -O-, more preferably -COO-,-
OCO- or represents a -CH ₂ COO-.

L is preferably an alkyl or alkenyl group having 8 to 32 carbon atoms which may be substituted. Examples of the substituent include a halogen atom (for example, a fluorine atom,
A chlorine atom, a bromine atom, ^{etc.), - O-D 3,} -COO-D 3,
—OCO—D ³ (where D ³ represents an alkyl group having 6 to 22 carbon atoms, and examples thereof include a hexyl group, an octyl group, a decyl group, a dodecyl group, a hexadecyl group, and an octadecyl group). . More preferably, L represents an alkyl or alkenyl group having 10 to 22 carbon atoms. For example, decyl, dodecyl, tridecyl, tetradecyl, hexadecyl, octadecyl, docosyl, eicosyl, decenyl, dodecenyl, tridecenyl, tetradecenyl, pentadecenyl, hexadecenyl, heptadecenyl, octadecenyl,
And a docosenyl group.

B¹And b^TwoAre the same or different
Preferably, a hydrogen atom, a halogen atom (for example, a fluorine atom)
Atom, chlorine atom, bromine atom, etc.), cyano group, carbon number 1-3
An alkyl group of -COO-D¹Or -CH_TwoCOO-D
¹(Where D¹Is preferably an aliphatic group having 1 to 22 carbon atoms
Represents, for example, a methyl group, an ethyl group, a propyl group,
Tyl, hexyl, octyl, decyl, dodecyl
Group, tridecyl group, tetradecyl group, hexadecyl group,
Octadecyl, docosyl, pentenyl, hexenic
Group, heptenyl group, octenyl group, decenyl group, dode
Senyl, tetradecenyl, hexadecenyl, octyl
Tadecenyl group and the like, and these aliphatic groups are
Which may have the same substituents as those described above). Yo
More preferably, b¹And b^TwoRepresents a hydrogen atom and a carbon atom, respectively.
An alkyl group of Formulas 1 to 3 (for example, a methyl group, an ethyl group,
Propyl group), -COO-D¹Or -CH_TwoCOO-
D ¹(Where D¹Is more preferably an C 1 -C 12
Represents an alkyl group or an alkenyl group, for example, methyl
Group, ethyl group, propyl group, butyl group, hexyl group,
Octyl, decyl, dodecyl, pentenyl, hexyl
Cenyl, heptenyl, octenyl, decenyl,
And the like. These alkyl groups and alkenyl groups are the same as those described above.
L may have the same substituents as those represented by L)
You.

The dispersion stabilizing resin (P) of the present invention comprises: a monomer corresponding to the repeating unit represented by the above general formula (II);
It may be a polymer obtained by copolymerizing the monomer with another monomer that can be copolymerized, and in which a part of the polymer main chain is crosslinked.

The other monomer which can be copolymerized may be any as long as it contains a polymerizable double bond group. Examples thereof include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid and itaconic acid; Ester derivatives or amide derivatives of unsaturated carboxylic acids having a number of 6 or less; vinyl esters or allyl esters of carboxylic acids; styrenes; methacrylonitrile; acrylonitrile; heterocyclic compounds containing a polymerizable double bond group. . More specifically, a compound having the same content as the above-mentioned monomer (A) to be insolubilized may be used.

In the polymer component of the dispersion stabilizing resin (P), the content of the repeating unit represented by the general formula (II) is at least 50% by mass, preferably at least 60% by mass, more preferably at least 70% by mass. % Or more.

As a method for introducing a crosslinked structure into the polymer of the dispersion stabilizing resin (P), a generally known method can be used. That is, in the polymerization reaction of the monomer, a method of performing polymerization in the presence of a polyfunctional monomer, and a method of including a functional group in the polymer that allows a crosslinking reaction to proceed and crosslinking by a polymer reaction.

In the production of the dispersion stabilizing resin (P) of the present invention, the production method is simple (for example, a long-term reaction is required, the reaction is not quantitative, or a reaction promoting aid is used to remove impurities. Therefore, the crosslinking reaction by polymerization is effective.

The crosslinking reaction by polymerization is preferably a polymerization reaction for producing a dispersion stabilizing resin (P), wherein a monomer having two or more polymerizable functional groups (polyfunctional monomer) is preferably used. This is a method of crosslinking between polymer chains by polymerizing with a monomer corresponding to the repeating unit represented by the formula (II).

As the polymerizable functional group, specifically, CH ₂ ＝
CH—, CH ₂ ＣＨCH—CH ₂ —, CH ₂ ＣＨCH—CO
—O—, CH ₂ ＣC (CH ₃ ) —CO—O—, CH ₃ —C
H = CH-CO-O-, CH 2 = CH-CONH-, C
H ₂ ＣC (CH ₃ ) —CONH—, CH ₂ ＣＨC (CH ₂ ) —
_{CONHCOO-, CH 2 = C (CH} 3) -CONHCO
_{NH-, CH 3 -CH = CH-} CONH-, CH 2 = C
_{H-O-CO-, CH 2} = C (CH 3) -O-CO-, C
_{H 2 = CH-CH 2 -O} -CO-, CH 2 = CH-NH
_{CO-, CH 2 = CH-CH} 2 -NHCO-, CH 2 =
CH—SO ₂ —, CH ₂ ＣＨCH—CO—, CH ₂ ＣＨCH
—O—, CH ₂ ＣＨCH—S— and the like can be mentioned.
The monomer having two or more polymerizable functional groups may be a monomer having two or more same or different polymerizable functional groups.

Specific examples of the monomer having two or more polymerizable functional groups include, as monomers having the same polymerizable functional group, styrene derivatives such as divinylbenzene and trivinylbenzene; Alcohols (eg, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol # 200, # 400,
# 600, 1,3-butylene glycol, neopentyl glycol, dipropyl glycol, polypropylene glycol, trimethylolpropane, trimethylolethane, pentaerythritol, etc.) or polyhydroxyphenol (eg, hydroquinone, resorcin, catechol and derivatives thereof) Esters, vinyl ethers or allyl ethers of methacrylic acid, acrylic acid or crotonic acid; dibasic acids (eg, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid,
Vinyl esters, allyl esters, vinyl amides or allyl amides of maleic acid, phthalic acid, itaconic acid and the like; polyamines (for example, ethylenediamine,
Condensates of 1,3-propylenediamine, 1,4-butylenediamine, etc.) with carboxylic acids having a vinyl group (eg, methacrylic acid, acrylic acid, crotonic acid, allyl acetic acid, etc.).

Further, as a monomer having a different polymerizable functional group, for example, a carboxylic acid having a vinyl group [for example, methacrylic acid, acrylic acid, methacryloyl acetic acid,
Reactants of acryloyl acetic acid, methacryloyl propionic acid, acryloyl propionic acid, itaconiloyl acetic acid, itaconiloyl propionic acid, carboxylic anhydride and alcohol or amine (for example, allyloxycarbonylpropionic acid, allyloxycarbonylacetic acid, 2-allyloxycarbonyl Ester derivatives or amide derivatives containing vinyl groups such as benzoic acid, allylaminocarbonylpropionic acid, etc.) (for example, vinyl methacrylate, vinyl acrylate, vinyl itaconate, allyl methacrylate, allyl acrylate, allyl itaconate, Vinyl methacryloyl acetate, vinyl methacryloyl propionate, allyl methacryloyl propionate, vinyl oxycarbonyl methyl methacrylate, vinyl oxycarboxy acrylate Methyloxycarbonylethylene ester, N-allylacrylamide, N-allylmethacrylamide, N-allylitaconamide, methacryloylpropionylallylamide, etc.); or allyl alcohols (for example, allylethanol, 1-allylpropanol, 1-allyl) Butanol, 1-allylhexanol, 2-allylbutanol, etc.) and a carboxylic acid containing a vinyl group.

The monomer having two or more polymerizable functional groups used in the present invention preferably accounts for 10% by mass of all the monomers.
The polymerization is carried out below, more preferably 8% by mass or less, to form the dispersion stabilizing resin soluble in the non-aqueous solvent of the present invention.

The dispersion stabilizing resin (P) used in the present invention
In a preferred embodiment, at least one of the polymer main chains is
One having a specific polar group bonded to one end [hereinafter referred to as dispersion stabilizing resin (PA) or resin (P
A). Specific polar groups include-
_{PO 3 H 2, -SO 3 H} , -COOH, -P (= O) (O
H) R ¹¹ [where R ¹¹ is a hydrocarbon group or —OR
¹² (R ¹² represents a hydrocarbon group)], -OH, formyl group, -CONR ¹³ R ¹⁴ , -SO ₂ NR ¹³ R ¹⁴ wherein R ¹³ and R ¹⁴ may be the same or different Often represents a hydrogen atom or a hydrocarbon group], a cyclic acid anhydride-containing group, and an amino group.

In the above polar group represented by —P (＝ O) (OH) R ¹¹ , the hydrocarbon group represented by R ¹¹ or R ¹² is preferably a hydrocarbon group having 1 to 10 carbon atoms. More preferably, an aliphatic group having 1 to 8 carbon atoms which may be substituted (for example, methyl, ethyl, propyl, butyl, pentyl, hexyl, butenyl, pentenyl, hexenyl, 2-chloroethyl) Group, 2-cyanoethyl group, cyclopentyl group, cyclohexyl group, benzyl group, phenethyl group, chlorobenzyl group, bromobenzyl group, etc.) or an aromatic group which may be substituted (for example,
Phenyl, tolyl, xylyl, mesityl, chlorophenyl, bromophenyl, methoxyphenyl, cyanophenyl, etc.).

The above -CONR ¹³ R ¹⁴ and -SO ₂ NR
^{In the} polar group represented by ¹³ R ¹⁴ , R ¹³ and R ¹⁴ are
Each may be the same or different and represents a hydrogen atom or a hydrocarbon group (preferably a hydrocarbon group having 1 to 8 carbon atoms which may be substituted). Specific examples of the hydrocarbon groups represented by R ¹³ and R ¹⁴ include the same as the hydrocarbon groups represented by R ¹¹ and R ¹² .

The cyclic acid anhydride-containing group is a group containing at least one cyclic acid anhydride. Examples of the cyclic acid anhydride include aliphatic dicarboxylic anhydride and aromatic dicarboxylic anhydride. Things.

Examples of the aliphatic dicarboxylic anhydride include:
Succinic anhydride, glutaconic anhydride, maleic anhydride, cyclopentane-1,2-dicarboxylic anhydride, cyclohexa-1,2-dicarboxylic anhydride, cyclohexene-1,2-dicarboxylic anhydride, 2,3-bicyclo [2.2.2] octanedicarboxylic anhydride and the like. These aliphatic dicarboxylic acids may be substituted with, for example, a halogen atom such as a chlorine atom or a bromine atom, or an alkyl group such as a methyl group, an ethyl group, a butyl group or a hexyl group.

Examples of the aromatic dicarboxylic anhydride include phthalic anhydride, naphthalene-dicarboxylic anhydride, pyridine-dicarboxylic anhydride, thiophene-dicarboxylic anhydride and the like. These aromatic dicarboxylic anhydrides include, for example, chlorine atoms, halogen atoms such as bromine atoms, alkyl groups such as methyl, ethyl, propyl, and butyl groups, hydroxyl groups, cyano groups, nitro groups, and alkoxycarbonyl groups. (As the alkoxy group,
For example, it may be substituted with a methoxy group, an ethoxy group and the like.

In the polar group, the amino group is represented by —NH ₂ ,
It represents an -NHR ¹⁵ or -NR ¹⁵ R ^16. R ¹⁵ and R ¹⁶ are
Each represents a hydrocarbon group having 1 to 8 carbon atoms, and preferably represents a hydrocarbon group having 1 to 7 carbon atoms.
And the same as the hydrocarbon group represented by

In the dispersion stabilizing resin (PA), the specific polar group may be directly bonded to one end of the polymer main chain, or may be bonded via a linking group. Examples of the linking group for linking the main chain portion and the specific polar group-containing component include a carbon atom-carbon atom bond (single bond or double bond) and a carbon atom-hetero atom bond (hetero atoms include, for example, oxygen atom, Sulfur atom, nitrogen atom, silicon atom, etc.) and any combination of heteroatom-heteroatom bond atomic groups.

[0081] As specific examples of the linking group, -CR ¹⁷ R ¹⁸ -
[Wherein R ¹⁷ and R ¹⁸ may be the same or different, and each represents a hydrogen atom, a halogen atom (a fluorine atom, a chlorine atom,
Bromine atom, etc.), cyano group, hydroxyl group, alkyl group (methyl group, ethyl group, propyl group, etc.). ],
- (CH = CH) -, - C 6 H 10 -, ( wherein, -C ₆
H ₁₀ - is, 1,2, 1,3, representing a 1,4-cyclohexylene. The same applies hereinafter), -Ph-, -O-, -S-,
^{-CO -, - NR 19 -,} - COO -, - SO 2 -, - C
_{^{ONR 19 -, - SO 2 NR}} 19 -, - NHCOO -, - N
^{HCONH -, - SiR 19 R 20} - [wherein, R ^19, R ²⁰
Represents a hydrogen atom or a hydrocarbon group having the same content as R11 in the above-mentioned polar group.], Or a single linking group selected from atomic groups or a combination of any two or more atomic groups. And a linking group.

The dispersion stabilizing resin (P) used in the present invention
A) is a mixture of a monomer corresponding to the repeating unit represented by the general formula (II), the above-mentioned polyfunctional monomer, and the above-mentioned chain transfer agent having a specific polar group. System compound, peroxide, etc.), in the above, without using the chain transfer agent, a method of polymerizing using a polymerization initiator containing the polar group,
In the above, a method using a compound containing the polar group for both the chain transfer agent and the polymerization initiator,
In the above three methods, a polymerization reaction is performed using a compound containing a functional group such as an amino group, a halogen atom, an epoxy group, or an acid halide group instead of the polar group as a substituent of a chain transfer agent or a polymerization initiator. Thereafter, it can be produced by a method of introducing the polar group by reacting with these functional groups by a polymer reaction.

Specifically, P. Dreyfuss, RPQuirk, Enc
ycl. Poly. Sci. Eng., 7, 551 (1987), Yoshiki Nakajo, Yuya Yamashita, "Dyes and Chemicals", 30, 232 (1985), Akira Ueda, Susumu Nagai, "Chemistry and Industry" 60, 57 (1986) ), Etc. and the literature cited therein.

As the chain transfer agent to be used, for example, a mercapto compound containing the specific polar group or a substituent which can be derived to the specific polar group (for example, thioglycolic acid,
Thiomalic acid, thiosalicylic acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid, 3-mercaptobutyric acid, N- (2-mercaptopropionyl) glycine,
2-mercaptonicotinic acid, 3- [N- (2-mercaptoethyl) carbamoyl] propionic acid, 3- [N-
(2-Mercaptoethyl) amino] propionic acid, N-
(3-mercaptopropionyl) alanine, 2-mercaptoethanesulfonic acid, 3-mercaptopropanesulfonic acid, 4-mercaptobutanesulfonic acid, 2-mercaptoethanol, 1-mercapto-2-propanol, 3
-Mercapto-2-butanol, mercaptophenol, 2-mercaptoethylamine, 2-mercaptoimidazole, 2-mergato-3-pyridinol, etc.) or the specific reactive group or a substituent which can be derived to the specific reactive group (E.g., iodoacetic acid, iodopropionic acid, 2-iodoethanol, 2-iodoethanesulfonic acid, 3-iodopropanesulfonic acid, etc.). Preferably, a mercapto compound is used.

Examples of the polymerization initiator containing a specific polar group or a substituent which can be derived to a specific polar group include, for example, azobis compounds {eg, 4,4′-azobis (4-cyanovaleric acid), 4'-azobis (4-cyanovaleric acid chloride), 2,2'-azobis (2-cyanopropanol), 2,2'-azobis (2-cyanopentanol), 2,2'-azobis [2- ( 5-hydroxy-
3,4,5,6-tetrahydropyrimidin-2-yl)
Propane], 2,2'-azobis {2-methyl-N-
[1,1-bis (hydroxymethyl) -2-hydroxyethyl] propioamide}, 2,2′-azobis {2-
Methyl-N- [1,1-bis (hydroxymethyl) ethyl] propioamide}, 2,2′-azobis [2-methyl-N- (2-hydroxyethyl) -propioamide], 2,2′-azobis (2 -Amidinopropane)｝, or a dithiocarbamate compound ｛for example,
Benzyl N-methyl-N-hydroxyethyldithiocarbamate, 2-carboxyethyl N, N-diethyldithiocarbamate, 3-hydroxypropyl N, N
-Dimethyldithiocarbamate} and the like.

The amount of use of these chain transfer agents or polymerization initiators is 0.05 to 100 parts by mass of all monomers.
15 parts by mass, preferably 0.1 to 10 parts by mass.

In another preferred embodiment of the dispersion stabilizing resin (P) of the present invention, a polymerizable double bond group represented by the above general formula (III) is attached to at least one terminal of the polymer main chain. Examples thereof include those formed by bonding (hereinafter, sometimes referred to as dispersion stabilizing resin (PB) or resin (PB)). The polymerizable double bond group may be any functional group that copolymerizes with the monomer (A) constituting the dispersed resin particles.

In the formula (III), V ¹ represents —COO—,
_{-OCO -, - (CH 2)} t COO -, - (CH 2) t OCO
-, - O -, - SO 2 -, - CONHCOO -, - CO
^{NHCONH -, - CON (D 2} ), - SO 2 N (D 2)
Or represents a phenylene group (here, D ² preferably represents a hydrogen atom or an alkyl group having 1 to 22 carbon atoms, and t represents an integer of 1 to 4). Specific embodiments of the phenylene group are the same as the phenylene group for V ² in the formula (V).

C ¹ and c ² may be the same or different and have the same meaning as b ¹ and b ^{2 in} formula (II), and represent the same contents. More preferably, one of b ¹ and b ² is a hydrogen atom.

In V ¹ , -CON (D ² )-,
-SO ^₂ N (D ₂₎ - in D ² is preferably a hydrogen atom or a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, heptyl group, octyl group, decyl group, a dodecyl group Represents an alkyl group.

The polymerizable double bond group may be directly bonded to one end of the polymer main chain, or may be bonded via an optional linking group. Examples of the connecting group include a carbon atom-carbon atom bond (single bond or double bond), a carbon atom-hetero atom bond (for example, an oxygen atom, a sulfur atom, a nitrogen atom, a silicon atom, etc.), a hetero atom -It is composed of any combination of heteroatom bond atomic groups. For example,

[0092]

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In the formula, z ¹ and z ² are each a hydrogen atom, a halogen atom (eg, a fluorine atom, a chlorine atom, a bromine atom, etc.), a cyano group, a hydroxyl group, an alkyl group (eg, a methyl group, an ethyl group, Propyl group). z
³ and z ⁴ are each a hydrogen atom, a hydrocarbon group having 1 to 8 carbon atoms (for example, methyl, ethyl, propyl, butyl, pentyl, hexyl, benzyl, phenethyl, phenyl, tolyl) group) or -OZ ⁵ (z
⁵ represents shown) the same contents as the hydrocarbon group in the z ^3), and the like.

The polymerizable double bond group represented by the general formula (III) bonded to one terminal of the polymer main chain as described above is specifically described below. In the following specific examples, A is -H,
Represents -CH ₃ or -CH ₂ COOCH _3, B represents -H or -CH _3. Further, n represents an integer of 2 to 10, m represents 2 or 3, t represents 1, 2 or 3, p represents an integer of 1 to 4, and q represents 1 or 2.

[0095]

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[0096]

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[0097]

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[0098]

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The dispersion stabilizing resin (PB) of the present invention having a polymerizable double bond group bonded to one end of the polymer main chain can be prepared by a conventional known radical polymerization (for example, iniferter method), anionic polymerization or cationic polymerization. The terminal of the living polymer obtained by polymerization is reacted with a reagent containing various double bond groups, or a specific reactive group (for example, -OH, -COOH, -SO
_{3 H, -NH 2, -SH,} -PO 3 H 2, -NCO, -NC
S,

[0100]

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-COCl, -SO ₂ Cl, etc.), and then introducing a polymerizable double bond group by a polymer reaction (method by ionic polymerization), or the above-mentioned specific compound in the molecule. After radical polymerization using a polymerization initiator and / or a chain transfer agent containing a reactive group of
It can be easily produced by a synthesis method such as a method of introducing a polymerizable double bond group by a polymer reaction utilizing a specific reactive group bonded to one end of the polymer main chain.

Specifically, Takayuki Otsu, Polymer, 33 (No.
3), 222 (1984), P. Dreyfuss & RPQuirk, Encycl. P
olym.Sci. Eng., 7, 551 (1987), Yoshiki Chujo, Yuya Yamashita, "Dyes and Chemicals", 30, 232 (1985), Akira Ueda, Susumu Nagai, "Chemistry and Industry", 60, 57 (1986), PFRempp & E.Franta,
Advances in Polymer Science, 58, 1 (1984), Koichi Ito `` Polymer Processing '', 35, 262 (1986), V. Percec, Applied
A polymerizable double bond group can be introduced according to a method described in a review such as Poymer Science, 285, 97 (1984) and the literature cited therein.

Specifically, the dispersion stabilizing resin (PB) is
(i) A mixture of at least one kind of monomer corresponding to the repeating unit represented by the general formula (II), the above-mentioned polyfunctional monomer and a chain transfer agent containing the above-mentioned specific reactive group in a molecule. Polymerization initiator (eg, azobis compound, peroxide, etc.)
(Ii) in (i), without using the chain transfer agent, a method of polymerizing using a polymerization initiator containing the specific reactive group in the molecule, or (iii) (i ), A method using a compound containing the above-mentioned specific reactive group in the molecule for both the chain transfer agent and the polymerization initiator, etc., having a cross-linked structure, and a specific terminal at one end of the polymer main chain A method in which a polymer having a reactive group bonded thereto is synthesized, and then a polymerizable double bond is introduced by a polymer reaction using the specific reactive group is used.

The amount of these chain transfer agents or polymerization initiators used is 0.1 to 1 with respect to 100 parts by mass of all monomers.
5 parts by mass, preferably 0.5 to 10 parts by mass. The chain transfer agent and the polymerization initiator used are the same as those of the resin (P
The same compounds as those exemplified in A) can be mentioned.

The dispersion stabilizing resin (P) of the present invention [resin (P
A) and the resin (PB)).
w) is preferably 2 × 10 ⁴ to 1 × 10 ⁶ , more preferably 3 × 10 ⁴ to 2 × 10 ⁵ .

By using a dispersion stabilizing resin (PA) having a specific polar group bonded to one end of the polymer main chain, the dispersion stabilizing resin (PA) is easily adsorbed on the insoluble resin particles. Further, by using a dispersion stabilizing resin (PB) containing a polymerizable double bond group at one end of the polymer main chain, the resin (PB) chemically bonds to the insoluble resin particles. Due to these facts, the so-called steric repulsion effect is brought about by the improvement of the affinity of the soluble component of the dispersion stabilizing resin (P) sufficiently adsorbed or chemically bonded to the dispersion resin particles to the dispersion medium, and the dispersibility is further improved. Can be

Next, in the present invention, a monofunctional compound having a specific substituent represented by the general formula (IV) and copolymerizable with the monomer (A), which is preferably used as a copolymer component of the resin particles. The functional monomer (D) will be described.

First, in the general formula (IV), the case where E ¹ represents an aliphatic group having 8 or more carbon atoms will be described in detail. As the aliphatic group having 8 or more carbon atoms of E ¹ , preferably an alkyl group having 10 or more carbon atoms which may be substituted or an alkenyl group having 10 or more carbon atoms which may be substituted is preferable.

U ¹ is preferably -COO-, -CON
^{H -, - CON (E 2} ) - ( wherein, E ² is preferably aliphatic group (the aliphatic group of 1 to 32 carbon atoms, such as alkyl groups, and the like alkenyl group or an aralkyl group) Or a substituent represented by the formula (IVa)), —OCO—, —CH ₂ OCO— or —O—.

C ¹ and c ² are the same or different and
Preferably a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, a cyano group, a methyl group, -COO-E ³ or -CH ₂
Represents COO-E ³ (however, E ³ preferably represents an alkyl group, alkenyl group, aralkyl group or cycloalkyl group having 32 or less carbon atoms).

In the formula (IV), U ¹ is -COO-, -CON
H- or -CON (E ²⁾ - represents, c ¹ and c
More preferably, ² is the same or different and represents a hydrogen atom, a fluorine atom, a chlorine atom, a cyano group or a methyl group.

In the monomer (D) represented by the above general formula (IV), when E ¹ represents an aliphatic group having 8 or more carbon atoms, specific examples thereof include a total of 10 to 10 carbon atoms. 32 aliphatic groups (the aliphatic group may contain a substituent such as a halogen atom, a hydroxyl group, an amino group, or an alkoxy group;
Or an oxygen atom, a sulfur atom, a hetero atom such as a nitrogen atom, and the like, and a carbon atom-carbon atom bond in its main chain may be interposed).
Esters of unsaturated carboxylic acids such as chloroacrylic acid, α-cyanoacrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid (for example, aliphatic groups such as decyl, dodecyl, tridecyl, tetradecyl,
Hexadecyl group, octadecyl group, docosyl group, dodecenyl group, hexadecenyl group, oleyl group, linoleyl group, docosenyl group, etc.); amides of the above-mentioned saturated carboxylic acids (the same as those shown in the above-mentioned esters as the aliphatic group) Vinyl esters or allyl esters of higher fatty acids (higher fatty acids include, for example, lauric acid, myristic acid, stearic acid, oleic acid, linoleic acid, behenic acid, etc.); or total carbon Vinyl ethers in which several 10 to 32 aliphatic groups are bonded to an oxygen atom (the aliphatic groups include the same aliphatic groups as those exemplified for the above unsaturated carboxylic esters) and the like. .

In the monomer (D) represented by the general formula (IV), E ¹ has a total number of atoms of 8 or more (excluding a hydrogen atom directly bonded to a carbon atom or a nitrogen atom).
The case of representing the substituent represented by a) will be described in detail.

A ¹ and A ² are the same or different and
It represents at least one group selected from the group represented by the general formula (IVb) and the hydrocarbon group having 1 to 18 carbon atoms. Here, when two or more groups are selected, it represents a group in which these two or more groups are bonded. Specifically, A ¹ and A ² are, for example, —C (R ²⁴ ) (R ²⁵ ) —
(Where R ²⁴ and R ²⁵ are the same or different and each represent a hydrogen atom, an alkyl group, a halogen atom, etc.),-
(CH = CH) -, cyclohexylene group (hereinafter, a cyclohexylene group - expressed in, "" -C ₆ H ₁₀ "- C ₆ H ₁₀
-"Includes 1,2-cyclohexylene group, 1,3-cyclohexylene group, 1,4-cyclohexylene group), and any combination of atomic groups such as the group represented by the general formula (IVb). It is composed.

When E ¹ represents a substituent represented by the general formula (IVa) having a total number of atoms of 8 or more, the bonding group (-U ¹ ) in the formula (IV)
-(A ¹ -B ¹ ) _m- (A ² -B ² ) _n -R ²¹ )
A “linking main chain” composed of U ¹ to R ²¹ (that is, U ¹ , A ¹ , B ¹ , A ² , B ² and R ²¹ ) has a total number of atoms constituting the linking main chain of 8 It is preferable that it is above.

Here, the number of atoms constituting the “linking main chain” means, for example, when U ¹ represents —COO— or —CONH—, an oxo group (＝ O group) or a hydrogen atom The carbon atoms, ether-type oxygen atoms, and nitrogen atoms that constitute the connecting main chain are included in the number of atoms. Therefore, -COO- and -CONH- have 2 atoms.
Counted as At the same time, when R ²¹ represents —C ₉ H ₁₉ , a hydrogen atom is not included in the number of atoms, and a carbon atom is included. Therefore, in this case, it is counted as 9 atoms.

Note that U ¹ represents —CON (E ² ) — and E ² represents a substituent represented by the general formula (IVa), that is, (− (A ¹ -B ¹ ) _m- (A ² -B ²⁾ when it represents an _n -R ^21), also connected backbone consists of E ² contained in the "binding main chain". Moreover A ^1, A ² is the formula (-B in case of having a group represented by ^{(IVb) 3 - (A 4} -B 4) p-R
²³ ) The group is also included in the aforementioned “linking main chain”.

In the above monomer (D) represented by the general formula (IV), when E ¹ represents a substituent represented by the general formula (IVa), specific examples include the following compounds. Can be mentioned.

The following formulas (D-1) to (D-19)
Here, each symbol represents the following contents. r ₁ : —H, —CH ₃ , —Cl or —CN, r ₂ : —H or —CH ₃ l: an integer of 2 to 10, p: an integer of 2 to 6, q: an integer of 2 to 4, m : An integer of 1 to 12, n: an integer of 4 to 18,

[0120]

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[0121]

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[0122]

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By using the monomer (D), the dispersion stability and redispersibility of the dispersed resin particles are further improved. This is because the copolymerization component corresponding to the monomer (D) has a high affinity for the dispersion medium and is oriented on the particle surface portion, whereby the affinity for the dispersion medium of the particle itself with the dispersion medium is obtained. This is presumed to increase the properties and suppress the aggregation and precipitation of the particles. When the monomer (D) is used, the amount used is preferably 0.5 to 20% by mass, more preferably 1 to 15% by mass of all the monomers.
It is.

In order to produce the dispersed resin particles used in the present invention, generally, the dispersion stabilizing resin (P) as described above,
The monomer (A), the monomer (B) and the monomer (C), and if necessary, the monomer (D) are mixed with benzoyl peroxide, azobisisobutyronitrile, butyl in a non-aqueous solvent. Heat polymerization may be performed in the presence of a polymerization initiator such as lithium. Specifically, in a mixed solution of the dispersion stabilizing resin (P), the monomer (A), the monomer (B) and the monomer (C), and if necessary, the monomer (D). A method in which a polymerization initiator is added, a monomer (A), a monomer (B), a monomer (C), and a monomer ( D) together with the polymerization initiator, or a mixture of the monomer (A) and the monomer (B) in a solution in which the dispersion stabilizing resin (P) is dissolved. Half of (A),
There is a method in which the monomer (C) and, if necessary, a mixture of the monomer (D) and the polymerization initiator are respectively simultaneously dropped, and any method can be used for the production.

The total amount of the monomers (A), (B), (C) and (D) is preferably from 10 to 100 parts by mass relative to 100 parts by mass of the non-aqueous solvent. Parts, more preferably 10 to 80 parts by mass. The amount of the dispersion stabilizing resin (P) is preferably 3 to 25 parts by mass, more preferably 5 to 20 parts by mass, based on 100 parts by mass of all the monomers used above. The amount of the polymerization initiator is suitably from 0.1 to 10% by mass of all the monomers. Further, the polymerization temperature is preferably about 40 to 180 ° C, more preferably 5 to 180 ° C.
0-120 ° C. The reaction time is preferably 3 to 15 hours.

When the above-mentioned polar solvents such as alcohols, ketones, ethers and esters are used in combination in the non-aqueous solvent used in the reaction, or unreacted products of monomers to be polymerized and granulated remain. In this case, it is preferable to remove the solvent by heating it to a temperature higher than the boiling point of the polar solvent or the monomer, or to remove the solvent by distillation under reduced pressure.

The non-aqueous dispersed resin particles produced according to the present invention as described above exist as fine particles having a uniform particle size distribution. Its average particle size is preferably 0.15
To 5 μm, more preferably 0.2 to 1.5 μm.
This particle size can be determined by CAPA-500 (manufactured by Horiba, Ltd.).

The weight average molecular weight (Mw) of the resin constituting the dispersed resin particles of the present invention (in terms of polystyrene by GPC method) is preferably 5 × 10 ³ to 1 × 10 ⁶ , more preferably 8 × 10 3. ³ is a to 5 × 10 ^5. As the thermophysical properties, the glass transition point is preferably from 0 ° C to 80 ° C or the softening point is preferably from 35 ° C to 120 ° C, more preferably from 10 ° C to 70 ° C or from 38 ° C to 9 ° C.
0 ° C.

The oil-based ink of the present invention is excellent in charge characteristics, dispersion stability, re-dispersibility, and storage stability of dispersed resin particles, and has good fast fixability after image formation, and is sufficient for printing. It maintains strength and shows high printing durability. That is, it shows very stable dispersibility, and particularly in a recording apparatus, has good dispersibility even when used repeatedly for a long time, and is easily redispersed.
No adhesion to any part of the device and no fouling is observed.

Furthermore, because of good fixability, a solid film is easily formed on the surface of the lithographic printing plate precursor when fixing by rapid processing such as heating after forming an ink image. Thereby, even in offset printing, printing of a large number of sheets (high printing durability) becomes possible. The oil-based ink of the present invention having the above effects is made possible by the non-aqueous latex provided by the present invention.

The dispersed resin particles in the oil-based ink used in the present invention exhibit positive charge. In order to adjust the charging characteristics of the oil-based ink, a technique of a wet developer for electrophotography can be appropriately used. Specifically, “Recent development and practical application of electrophotographic development systems and toner materials”, pp. 139-148, “Basic and Application of Electrophotographic Technology”, ed.
Page 05 (Corona Publishing, 1988), Yuji Harasaki "Electrophotography"
16 (No. 2), p. 44 (1977), etc.
This is done by using D) and other additives.

Examples of the charge adjusting agent include metal soaps, organic phosphoric acids or salts thereof, organic sulfonic acids or salts thereof,
Amphoteric surfactant compounds are useful. For example, as metal soaps, fatty acids having 6 to 24 carbon atoms (for example, 2-ethylhexanoic acid, 2-ethylcaproic acid, lauric acid,
Metal salts such as palmitic acid, elaidic acid, linoleic acid, ricinoleic acid, oleic acid, stearic acid, enanthic acid, naphthenic acid, ethylenediaminetetraacetic acid), resin acids, dialkyl succinic acids, alkyl phthalic acids, and alkyl salicylic acids Na, K, Li, as metals of
B, Al, Ti, Ca, Pb, Mn, Co, Zn, M
g, Ce, Ag, Cd, Zr, Cu, Fe, Ba, etc.)
(For example, US Pat. Nos. 3,411,936 and 3,90
0,412, JP-B-49-27707, JP-A-Sho 51
-37651, 52-38937, and 52-10
7837 and 53-123138).

The organic phosphoric acid or salts thereof have 3 carbon atoms.
Mono-, di- or trialkylphosphoric acid or dialkyldithiophosphoric acid or the like comprising alkyl groups (for example, British Patent Nos. 1,411,739 and 1,276,3)
63, etc.). Examples of the organic sulfonic acids and salts thereof include long-chain aliphatic sulfonic acids, long-chain alkylbenzenesulfonic acids, dialkylsulfosuccinic acids, and metal salts thereof (for example, Japanese Patent Publication No. 47-128128).
And JP-A-53-123138 and JP-A-51-47437.
No. 50-79640, and No. 53-30340).

Examples of the amphoteric surfactant include phospholipids such as lecithin and kephalin (for example, JP-B-51-47046).
Metal complexes of β-diketones such as β-alanines containing an alkyl group having 8 or more carbon atoms (JP-A-50-17642 and JP-A-49-17774).
707) and copolymers containing a maleic acid half-amide component (for example, JP-B-6-19596 and JP-B6-1959).
No. 5, No. 6-23865, etc.).

These charge control agents (CD) can be used alone or in combination of two or more. The charge control agent is preferably used in an amount of 0.001 to 1.0 part by mass with respect to 1000 parts by mass of the dispersion medium as the carrier liquid.

The oil-based ink of the present invention contains dispersed resin particles composed of at least the monomer (A), the monomer (B) and the monomer (C), and preferably contains a charge control agent (CD). It is made.

The oil-based ink of the present invention was prepared according to the above-mentioned WO 93/1.
When used in the method of forming an image by an electrostatic ink jet recording method involving concentration or coagulation disclosed in Japanese Patent No. 1866, loss of ink dots and deformation of the dot shape to be printed even at high printing speeds can be achieved. A high-definition image is formed without occurrence, and the thickness of the printed dot image is sufficiently maintained at 1 μm or more. This means that the positively charged resin particles in the oil-based ink are rapidly electrophoresed in the ink meniscus formed at the tip of the ejection electrode under an electrostatic field, and the particles are concentrated, resulting in an image signal. It is considered that the ejection is performed completely in response to the pulse voltage application.

Further, the oil-based ink of the present invention may be used after being stored for a long period of time or at a high temperature and high humidity (for example, 40 ° C./80 RH).
%), Shows the same performance as a fresh product immediately after ink production even when ink-jet recording is performed after storage. This is considered to be due to the fact that the charging characteristics of the oil-based ink of the present invention, in particular, the charging characteristics of the positively charged particles are stably maintained, and that the aggregation and precipitation of the particles are prevented by maintaining the above-mentioned dispersion stability.

If desired, various additives may be added. The upper limit of the total amount of these additives is regulated by the electric resistance of the oil-based ink. That is, if the electric resistance of the ink from which the dispersed particles are removed is lower than 10 ⁹ Ω · cm, it becomes difficult to obtain a high-quality continuous tone image. Therefore, the amount of each additive must be controlled within this limit. Is desirable.

The oil-based ink of the present invention preferably contains a coloring material as a coloring component together with the above-mentioned dispersed resin particles, for example, for plate inspection of a plate after plate making.

As the coloring material, any pigments and dyes conventionally used in oil-based ink compositions or liquid developers for electrophotography can be used.

Regarding pigments, those generally used in the technical field of printing can be used irrespective of inorganic pigments and organic pigments. 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 pigment, phthalocyanine pigment , Quinacridone pigments, isoindolinone pigments, dioxazine pigments, threne pigments, perylene pigments, perinone pigments, thioindigo pigments, quinophthalone pigments, metal complex pigments, and other conventionally known pigments are particularly limited. It can be used without.

As the dyes, azo dyes, metal complex 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 preferred.

These pigments and dyes may be used alone or in appropriate combination, but may be contained in the range of 0.05 to 20% by mass based on the whole ink. desirable.

These coloring materials may be dispersed in a non-aqueous solvent as dispersed particles in the non-aqueous solvent separately from the dispersed resin particles, or may be contained in the dispersed resin particles. One of the methods for adding the dye is to dye the dispersed resin material with an appropriate dye as described in JP-A-57-48738. Another method is disclosed in JP-A-53-5 / 78.
As disclosed in JP-A No. 4029 and the like, there is a method of chemically bonding a dispersing resin and a dye.
As described in, for example, No. 22555, there is a method of producing a dye-containing copolymer by using a monomer containing a dye in advance when producing by a polymerization granulation method.

Next, an image forming method by an electrostatic ink jet method using the oil-based ink of the present invention will be described. Here, a method of forming an image (plate making) using a printing original plate as an ink receiving material to form a printing plate will be described as an example.

The printing original plate is roughly classified into an original plate having a hydrophilic surface capable of lithographic printing and an original plate having a hydrophobic surface, and any of them can be used. The former printing original plate includes those in which the support itself has a hydrophilic surface and those in which a layer having a hydrophilic surface is provided on the support.

The water-resistant support having a lithographically printable hydrophilic surface may be any as long as it provides a hydrophilic surface suitable for lithographic printing, and the support conventionally used for offset printing plates can be used as it is. it can. Specifically, bimetal plates such as aluminum plates, zinc plates, copper-aluminum plates, copper-stainless steel plates, chromium-copper plates, chromium-copper-aluminum plates, chromium-lead-iron plates, chromium-copper-stainless steel plates, etc. A substrate having a hydrophilic surface such as a trimetal plate is used. Its thickness is 0.1-3 mm, especially 0.1
１1 mm is preferred.

In the case of a support having an aluminum surface, a surface treatment such as graining treatment, immersion treatment in an aqueous solution of sodium silicate, potassium fluorozirconate, phosphate or the like, or anodic oxidation treatment is performed. Is preferred. Further, as described in U.S. Pat. No. 2,714,066, an aluminum plate grained and then immersed in an aqueous solution of sodium silicate is disclosed in JP-B-47-51.
As described in No. 25, a material obtained by subjecting an aluminum plate to anodizing treatment and then immersing the plate in an aqueous solution of an alkali metal silicate is also preferably used.

The anodizing treatment may be performed, for example, by using one or more of an aqueous solution or a non-aqueous solution of an inorganic acid such as phosphoric acid, chromic acid, sulfur, boric acid, or an organic acid such as oxalic acid or sulfamic acid, or a salt thereof. It is carried out by flowing a current in the combined electrolyte using the aluminum plate as an anode. Also, silicate electrodeposition as described in U.S. Pat. No. 3,658,662 is effective. The treatment with polyvinyl sulfonic acid described in West German Patent Publication No. 1,621,478 is also suitable.

According to the combination of the ink and the recording method of the present invention, even when an image is formed on a metal surface, the ink is printed in a state in which the particles in the ink are sufficiently concentrated so that the ink bleeds on the printed surface. No image bleeding occurs.

These surface treatments are performed not only to make the surface of the support hydrophilic, but also to improve the adhesion to the ink image provided thereon. A surface layer may be provided on the surface of the support in order to adjust the adhesion between the support and the ink image.

When a plastic sheet or paper is used as a support, a portion provided with a hydrophilic surface layer is provided since the portion other than the ink image portion must be hydrophilic. Specifically, a known direct-drawing lithographic printing original plate or a plate material having a layer similar to the image receiving layer of the original plate can be used.

For example, as the image receiving layer, there is an image receiving layer composed mainly of a water-soluble binder, an inorganic pigment and a waterproofing agent. As the binder, PVA, modified PVA such as carboxy PVA, starch and its derivatives, CM
Water-soluble resins such as C, hydroxyethylcellulose, casein, gelatin, polyvinylpyrrolidone, vinyl acetate-crotonic acid copolymer, and styrene-maleic acid copolymer are used.

Examples of the water-proofing agent include initial condensates of aminoblasts such as glyoxal, melamine formaldehyde resin and urea formaldehyde resin, modified polyamide resins such as methylolated polyamide resins, polyamide / polyamine / epichlorohydrin adducts, polyamide epichlorohydrin resins, modified Polyamide polyimide resin and the like can be mentioned. Examples of the inorganic pigment include kaolin, clay, calcium carbonate, silica, titanium oxide, zinc oxide, barium sulfate, and alumina, and silica is preferred.

In addition, a crosslinking agent such as ammonium chloride and a silane coupling agent can be used in the image receiving layer.

On the other hand, in a printing master having an image receiving layer composed of a hydrophobic surface, after forming an image, the non-image portion is rendered insensitive by a desensitizing treatment (that is, the non-image portion is treated with a hydrophilic surface which is repellent to printing ink). Conversion) to make a printing plate.

These printing masters include a printing master having an image receiving layer containing at least zinc oxide and a binder resin, and a hydrophobic binder formed by a desensitizing treatment (treatment liquid, light irradiation, heat treatment, etc.). A printing plate having an image receiving layer containing at least a binder resin which chemically converts the binder resin into a hydrophilic binder resin (for example, JP-A-1-226394,
Japanese Patent Publication No. 7-94191).

The lithographic printing plate precursor having an image receiving layer containing at least zinc oxide and a binder resin will be described.

The zinc oxide to be used is described in, for example, “Pigment Handbook”, pages 319, edited by Japan Pigment Technical Association, Seibundo Co., Ltd.
(1968), zinc oxide, zinc white,
Any of those commercially available as wet zinc white or activated zinc white may be used. That is, zinc oxide includes, as a dry method, a French method (indirect method), an American method (direct method) and a wet method, depending on the starting materials and the production method. For example, Shodo Chemical Co., Ltd., Sakai Chemical ( Co., Ltd.), Hakusui Chemical Co., Ltd., Honjo Chemical Co., Ltd., Toho Zinc Co., Ltd.,
Examples include those commercially available from various companies such as Mitsui Kinzoku Kogyo.

The content of zinc oxide in the image receiving layer was 7
It is preferably from 5 to 90% by mass, more preferably from 78 to 88% by mass. If the amount of zinc oxide is too small, hydrophilization of the surface of the image receiving layer by the desensitizing treatment becomes insufficient. On the other hand, if the amount is too large, the necessary strength of the image receiving layer cannot be secured, which is not preferable.

As described above, the binder resin provided to the image receiving layer is a hydrophobic resin constituting the image receiving layer together with zinc oxide, and has a molecular weight of a mass average molecular weight Mw.
Preferably from 10 ³ to 10 ⁶ , more preferably from 5 × 10 ³ to
It is 5 × 10 ⁵ . Further, the glass transition point of this resin is preferably 0 ° C to 120 ° C, more preferably 10 ° C to 90 ° C.
° C.

Specifically, styrene copolymer, methacrylate copolymer, acrylate copolymer, vinyl acetate copolymer, polyvinyl butyral, alkyd resin, epoxy resin, epoxy ester resin, polyester resin, polyurethane resin and the like can be mentioned. Can be These resins may be used alone or in combination of two or more.

In the image receiving layer, together with the above components,
Other components may be contained. Other components that may be included are other inorganic pigments of zinc oxide, such as kaolin, clay, calcium carbonate, barium carbonate, calcium sulfate, barium sulfate, magnesium carbonate, oxides Examples include titanium, silica, and alumina. When these other inorganic pigments are used in combination, it is desirable to use them in a range not exceeding 20 parts by mass with respect to 100 parts by mass of zinc oxide.

Further, in order to improve the desensitization of the image receiving layer, JP-A-4-201387 and JP-A-4-223196 are known.
No. 4-319494, No. 5-58071, No. 4
Resin particles such as acrylic acid resin particles containing a specific functional group described in JP-A-353495 and JP-A-5-119545 may also be contained. These resin particles are usually spherical, and preferably have an average particle size of 0.1 to 2 μm. The content of the resin particles is preferably 20% by mass or less of the components of the image receiving layer.

By using these other inorganic pigments or resin particles, the non-image area is sufficiently desensitized (hydrophilic) by the desensitization treatment, the background stain on the printed matter is suppressed, and the image area is reduced. It is sufficiently adhered to the image receiving layer, and sufficient printing durability can be obtained without causing image defects even when the number of printed sheets increases.

In addition, a crosslinking agent may be added to the image receiving layer in order to further improve the film strength.

The binder resin is preferably cured by light and / or heat after the application of the image receiving layer composition. In order to carry out thermosetting, for example, the drying conditions are made stricter than the drying conditions at the time of preparing the conventional image receiving layer. For example, it is preferable to set the drying conditions to a high temperature and / or a long time, or to further heat after drying the coating solvent.
For example, the treatment is performed at 60 ° C to 150 ° C for 5 to 120 minutes. When a reaction accelerator is used in combination, the treatment can be performed under milder conditions.

As a method of curing by irradiation with light, a specific functional group in the resin may be irradiated with light by chemically active light. The chemical actinic ray may be any of visible ray, ultraviolet ray, far ultraviolet ray, electron beam, X-ray, γ ray, α ray and the like, but is preferably ultraviolet ray, more preferably a ray having a wavelength of 310 nm to 500 nm. . Generally, a low-pressure, high-pressure or ultra-high-pressure mercury lamp, a halogen lamp, or the like is used. The light irradiation treatment can be sufficiently carried out by irradiation from a distance of 5 cm to 50 cm for 10 seconds to 10 minutes.

The thickness of the image receiving layer is from 3 to 3 in terms of the coating amount of the image receiving layer composition per m ^{2 of} the printing plate precursor (after drying).
It is preferred to be about 30 g. The image receiving layer is usually 3 to 50 vol%, preferably 10 to 40 vol%.
It is preferable to have a porosity of the order.

The image receiving layer is provided on a water-resistant support. As the water-resistant support, paper, a plastic film or a paper or a plastic film laminated with a metal foil, which has been subjected to a water-resistant treatment can be used.

The support preferably has a highly smooth surface. That is, the smoothness of the surface on the side adjacent to the image receiving layer is adjusted to a Beck smoothness of 300 (sec / 10 ml) or more, preferably 900 to 3000 (sec / 10 ml), and more preferably. 1000-300
It is preferably 0 (second / 10 ml).

By regulating the smoothness of the surface of the support on the side adjacent to the image receiving layer to a Beck smoothness of 300 (sec / 10 ml) or more, image reproducibility and printing durability can be further improved. . Such an improvement effect is obtained even if the smoothness of the image receiving layer surface itself is the same, and the adhesion between the image portion and the image receiving layer is improved by increasing the smoothness of the support surface. it is conceivable that.

Here, the Beck smoothness can be measured by a Beck smoothness tester. A Beck smoothness tester presses a test piece at a constant pressure (1 kg / cm ² ) on a highly smooth finished circular glass plate with a hole in the center, and a fixed amount (10 ml) under reduced pressure. It measures the time required for air to pass between the glass surface and the specimen.

The highly smooth surface of such a water-resistant support refers to a surface to which an image receiving layer is directly applied. For example, when an underlayer or an overcoat layer described later is provided on the support, , The surface of the underlayer or overcoat layer. As a result, the image receiving layer whose surface condition has been adjusted as described above is sufficiently retained without receiving the unevenness of the surface of the support, and the image quality can be further improved.

As a method for setting the smoothness within the range, various conventionally known methods can be used. Specifically, by a method of melting and bonding the substrate surface with a resin, a method such as a calendar strengthening method using a highly smooth heat roller,
A method of adjusting the Beck smoothness of the surface of the support can be used.

As a method for melting and bonding the above resins, it is preferable that the resin is coated by an extrusion lamination method. By coating by this extrusion lamination method, a support having a desired smoothness can be produced. The extrusion laminating method is a method in which a resin is melted, formed into a film, immediately pressure-bonded to base paper, and then cooled and laminated, and various apparatuses are known. The thickness of the resin layer laminated in this manner is 10 μm from the viewpoint of production stability.
That is all. Preferably it is 10 μm to 30 μm.

Further, as described above, an under layer is provided between the support and the image receiving layer for the purpose of improving water resistance and interlayer adhesion, and a curl is provided on the surface of the support opposite to the image receiving layer to prevent curling. A back coat layer (back layer) can be provided, and the back coat layer has a smoothness of 150 to
It is preferably in the range of 700 (sec / 10 ml).
Accordingly, when the printing plate is supplied to the offset printing press, the printing plate is accurately set on the printing press without causing displacement or slippage.

When the smoothness of the underlayer and the backcoat layer of such a support are individually adjusted, for example, calendering is performed once after the underlayer is formed, and calendering is performed again after the backcoat layer is formed. In addition, the process of calendar processing is performed multiple times,
It is desirable to control the smoothness by a combination of adjusting the composition of the under layer and the back coat layer, for example, the proportion and particle size of the pigment, and adjusting the calendering conditions as described below.

Examples of the substrate used for the printing original plate include substrates such as wood pulp paper, synthetic pulp paper, mixed paper of wood pulp and synthetic pulp, non-woven fabric, plastic film, cloth, metal sheet, and composite sheet materials thereof. Can be used as it is. Also, to obtain a specific smoothness,
And in order to adjust the water resistance and other properties, the above substrate is impregnated with a coating material composed of a hydrophobic resin, a water-dispersible or water-soluble resin, a pigment, or the like used for an under layer or a back coat layer described below. You may.

In order to satisfy the printing suitability required for the lithographic printing plate precursor, for example, recording characteristics, water resistance, durability and the like, and to adjust the desired smoothness as described above, an under layer and a back coat layer are formed on the substrate. It is preferable to use a support provided with. Such an under layer and a back coat layer are formed by applying a coating solution containing a resin, a pigment, and the like on a support, drying and laminating the coating solution.
Various resins are appropriately selected and used as the resin used here. Specifically, examples of the hydrophobic resin include an acrylic resin, a vinyl chloride resin, a styrene resin, a urethane resin, a vinylidene chloride resin, and a vinyl acetate resin.Examples of the hydrophilic resin include polyvinyl resin. Alcohol resins, cellulose derivatives, starch and derivatives thereof, polyacrylamide resins, styrene-maleic anhydride copolymers and the like can be mentioned.

Examples of the pigment include clay, kaolin, talc, diatomaceous earth, calcium carbonate, aluminum hydroxide, magnesium hydroxide, titanium oxide, mica and the like. These pigments are used to achieve the desired smoothness.
It is preferable to appropriately select and use the particle size. For example, since a relatively high degree of smoothness is required in the under layer, a small particle size or a large particle is cut to specifically 8 μm or less, preferably Preferably, a pigment having a particle size of about 0.5 to 5 μm is used. Further, since a lower smoothness is required in the back coat layer as compared with the under layer, a larger particle size, specifically, 0.5 to 10
A pigment having a particle size of about μm is preferably used. The pigment as described above is preferably used in a ratio of 80 to 150 parts by mass in the under layer and 80 to 200 parts by mass in the back coat layer, based on 100 parts by mass of the resin. In order to obtain excellent water resistance, it is effective for the under layer and the back coat layer to contain a water-resistant agent such as a melamine resin or a polyamide epichlorohydrin resin. The particle size can be measured by a scanning electron microscope (SEM) photograph. When the particles are not spherical, the diameter is obtained by converting the projected area into a circle.

To prepare a lithographic printing plate precursor, a solution containing an underlayer component is coated on one side of the support, if necessary, to form an underlayer by drying, and if necessary, a backing layer is formed on the other side. After forming a back coat layer by applying and drying a solution containing a coating layer component, a coating solution containing an image receiving layer component may be applied and dried to form an image receiving layer. Note that the image-receiving layer, the under layer, the coating amount of the backcoat layer are each 1 to 30 g / m ^2, in particular 6~20g / m ² is suitable. Preferably, the water-resistant support provided with an under layer or a back coat layer has a thickness of 90 to 1
It is in the range of 30 μm, more preferably in the range of 100 to 120 μm.

Next, a method of forming an image on the lithographic printing original plate (hereinafter also referred to as “master”) will be described. FIG. 1 shows an example of an apparatus system for performing such a method. The apparatus system shown in FIG. 1 has an ink jet recording apparatus 1 using oil-based ink.

As shown in FIG. 1, first, pattern information of an image (figure or text) to be formed on the master 2 is transmitted from an information supply source such as a computer 3 through a transmission means such as a bus 4 to an oil-based ink. Is supplied to the ink jet recording apparatus 1 that uses. The ink jet recording head 10 of the recording apparatus 1 stores oil-based ink therein, and when the master 2 passes through the recording apparatus 1, ejects minute droplets of the ink to the master 2 according to the information. Thereby, ink adheres to the master 2 in the pattern. Thus, an image is formed on the master 2 to obtain a plate-making master (plate-making printing original plate).

FIGS. 2 and 3 show examples of the structure of an ink jet recording apparatus as in the apparatus system shown in FIG. FIG. 2 is a view showing a part of the head of such an ink jet recording apparatus, and FIG. 3 is a view for further explaining the structure thereof.

As shown in FIG. 2, the ink jet recording head 10 provided in the ink jet recording apparatus comprises a head body 14 made of an insulating material such as plastic or ceramic, and meniscus regulating plates 15 and 16. In the figure, reference numeral 17 denotes an ejection electrode for applying a voltage to perform ejection. Fig. 3 with the restriction plate removed from the head
The head body will be described in detail below.

The head main body 14 is provided with a plurality of ink grooves 18 for circulating ink, perpendicular to the edge of the head main body, and an ejection electrode 17 is provided therein.
Two adjacent ink grooves form one cell, and ejection parts 20, 20 'are provided at the end of the partition wall 19 at the center. In the ejection portions 20 and 20 ′, the partition walls are thinner than the other partition portions 25 and are sharpened. The tip of the discharge unit may be slightly chamfered as in 20 '. Although only two cells are shown in the figure, the cells are separated by a partition 21 and the tip 22 thereof is formed by a discharge unit 20.
It is chamfered so as to be retracted from 20 '.

[0189] Ink is supplied to the head from an I direction through an ink groove by an ink supply means (not shown) to supply the ink to a discharge section. Excess ink is collected in the O direction by an ink collecting means (not shown).
As a result, fresh ink is always supplied to the ejection unit. In this state, by applying a voltage to the discharge electrode against a counter electrode (not shown) which is provided in a form opposing the discharge unit and holds the printing original on the surface, ink is discharged from the discharge unit, and An image is formed on the original.

As described above, on the lithographic printing original plate,
An image is formed by an ink-jet method using oil-based ink, and plate making is performed. When the lithographic printing plate precursor used comprises a hydrophilic surface layer, it is used as it is as a printing plate for offset printing.

On the other hand, in the case of a lithographic printing original plate accompanied by desensitization, a non-image portion is desensitized by surface treatment with a desensitizing solution to prepare a printing plate. Desensitization of zinc oxide
Conventionally, as this type of desensitizing treatment solution, a cyanide-containing treatment solution containing ferrocyanide salt, ferricyan salt as a main component, an ammine cobalt complex, phytic acid and derivatives thereof, and a cyan-free treatment containing a guanidine derivative as a main component Liquids, treatment liquids containing an inorganic or organic acid which forms a chelate with zinc ions as a main component, treatment liquids containing a water-soluble polymer, and the like are known.

For example, as a cyanide-containing treatment solution,
JP-B-44-9045, JP-B-46-39403, JP-A-52-76101, JP-A-57-107889, and JP-A-57-107889.
4-117201 and the like. Phytic acid-based compound-containing treatment solutions are disclosed in JP-A-53-83.
No. 807, No. 53-83805, No. 53-10210
No. 2, No. 53-109701, No. 53-127003
And Nos. 54-2803 and 54-44901.

Examples of the treating solution containing a metal complex compound such as a cobalt complex include JP-A-53-104301 and JP-A-53-104301.
No. 140103, No. 54-18304, Tokuhei 43-
No. 28404. As an inorganic or organic acid-containing treatment solution, JP-B-39-13702,
Nos. 40-10308, 43-28408, 40
-26124 and JP-A-51-118501.

Examples of the guanidine compound-containing treating solution include those described in JP-A-56-11695. As a processing solution containing a water-soluble polymer, Japanese Patent Application Laid-Open
-126302, 52-134501, 53-
49506, 53-59022, 53-104
No. 302, JP-B-38-9665 and 39-2226
3, No. 40-763, No. 40-2202, and JP-A-49-36402.

In any of the above desensitizing treatments,
Zinc oxide in the surface layer ionizes into zinc ions,
It is believed that these ions cause a chelation reaction with a compound forming a chelate in the desensitizing solution to form a zinc chelate, which is deposited in the surface layer and hydrophilized.

The desensitizing treatment is usually performed at room temperature (15 ° C. to 35 ° C.).
) For about 2 to 60 seconds. Using this printing plate, several thousand sheets of offset printing are possible using dampening water.

[0197]

The following are examples of the dispersion stabilizing resin used in the present invention,
The present invention will be described in more detail with reference to Production Examples and Examples of resin particles (latex particles), but the present invention is not limited thereto.

Production Example 1 of Dispersion Stabilizing Resin (P) 1: Resin (P-1) A mixed solution of 100 g of octadecyl methacrylate, 1.0 g of divinylbenzene and 200 g of toluene was heated to 85 ° C. while stirring under a nitrogen stream. . 2,2'-azobis (isobutyronitrile) (abbreviated as AIB.
N. ) Was added and reacted for 4 hours. Further, A. I.
B. N. Was added and reacted for 2 hours. I.
B. N. Was added and reacted for 2 hours. After cooling, the mixed solution was reprecipitated in 1.5 l of methanol, and the powder was collected by filtration and dried to obtain 88 g of a white powder. The mass average molecular weight (Mw) of the obtained polymer was 3.3 × 10 ⁴ (polystyrene-equivalent value according to GPC; the same applies hereinafter).

Production Examples 2 to 6 of Dispersion Stabilizing Resin (P): Resins (P-2) to (P-6) In Production Example 1 of Dispersion Stabilizing Resin (P), instead of octadecyl methacrylate and divinylbenzene, Each dispersion stabilizing resin was produced in exactly the same manner as in Production Example 1 except that the monomers and polyfunctional monomers shown in Table-A below were used. Mw of each resin was in the range of 3 × 10 ^{4 to} 5 × 10 ⁴ .

[0200]

[Table 1]

Production Example 1 of Resin for Stabilizing Dispersion (PA) 1: Resin (PA-1) 95 g of octadecyl methacrylate, 3 g of thioglycolic acid, 5.0 g of divinylbenzene and 200 g of toluene
g of the mixed solution was heated to a temperature of 85 ° C. while stirring under a nitrogen stream. 0.8 g of 1,1'-azobis (cyclohexane-1-carbonitrile) (abbreviated as ACHN) was added and reacted for 4 hours. Further, A. C. H. N. Was added and reacted for 2 hours. C. H. N. Was added and reacted for 2 hours. After cooling, the mixed solution was reprecipitated in 1.5 l of methanol, and the powder was collected by filtration and dried to obtain 88 g of a white powder. Mw of the obtained polymer is 3
× 10 ⁴ .

Production Examples 2-8 of Dispersion Stabilizing Resin (PA):
Resins (PA-2) to (PA-8) In Production Example 1 of dispersion stabilizing resin (PA), in place of octadecyl methacrylate and divinylbenzene, monomers and polyfunctional monomers shown in Table B below were used. Is
Each dispersion stabilizing resin was produced in exactly the same manner as in Production Example 1. The Mw of each resin ranged from 2.5 × 10 ⁴ to 4 × 10 ⁴ .

[0203]

[Table 2]

Production Examples of Dispersion Stabilizing Resin (PA) 9 to 14:
Resins (PA-9) to (PA-14) Except for using the mercapto compounds shown in Table C below in place of thioglycolic acid in Production Example 1 of dispersion stabilizing resin (PA), the same procedure as in Production Example 1 was carried out. By operation, each dispersion stabilizing resin was manufactured.

[0205]

[Table 3]

Production Example 15 of Dispersion Stabilizing Resin (PA) Resin (PA-15) A mixed solution of 99.5 g of hexadecyl methacrylate, 0.5 g of divinylbenzene, 150 g of toluene and 50 g of isopropyl alcohol was stirred under a nitrogen stream. Heated to a temperature of 90 ° C. 6 g of 2,2'-azobis (4-cyanovaleric acid) (abbreviated as ACV) was added and reacted for 8 hours. After cooling, the mixed solution was reprecipitated in 1.5 liters of methanol, and the powder was collected by filtration and dried to obtain 83 g of a white powder.
I got Mw of the obtained polymer was 6.5 × 10 ⁴ .

Production Example 16 of Dispersion Stabilizing Resin (PA) Resin (PA-16) 92 g of docosyl methacrylate, polyethylene glycol diacrylate # 400 (manufactured by Okamura Oil Co., Ltd.) 1.5
g, 150 g of toluene and 50 g of ethanol were heated to a temperature of 80 ° C. while stirring under a nitrogen stream.
8 g of 4,4'-azobis (4-cyanopentanol)
The reaction was performed for 8 hours. After cooling, the mixed solution was reprecipitated in 1.5 liter of methanol, and the powder was collected by filtration and dried to obtain 78 g of a white powder. Mw of the obtained polymer was 4.1 × 10 ⁴ .

Production Example 17 of Dispersion Stabilizing Resin (PA) Resin (PA-17) A mixed solution of 95 g of octadecyl methacrylate, 5 g of 2-mercaptoethylamine, 5 g of divinylbenzene and 200 g of toluene was stirred at a temperature of 85 under a nitrogen stream.
Warmed to ° C. A. C. H. N. Was added and reacted for 8 hours. Next, 8 g of glutaconic anhydride and 1 ml of concentrated sulfuric acid were added and reacted at a temperature of 100 ° C. for 6 hours. After cooling, the mixed solution was reprecipitated in 1.5 liters of methanol, and the powder was collected by filtration and dried to obtain 83 g of a white powder.
I got Mw of the obtained polymer was 3.1 × 10 ⁴ .

Production Example of Dispersion Stabilizing Resin (PB) 1: Resin (PB-1) 100 g of octadecyl methacrylate, 3 g of thioglycolic acid, 5.0 g of divinylbenzene and toluene 20
0 g of the mixed solution was heated to a temperature of 85 ° C. while stirring under a nitrogen stream. A. C. H. N. Was added and reacted for 4 hours. Further, A. C. H. N. Was added and reacted for 2 hours. C. H. Add 0.2 g of N and add 2
Reacted for hours. After cooling, 10 g of 2-hydroxyethyl methacrylate was added and the temperature was set at 25C. To this solution, a mixed solution of 16 g of dicyclohexylcarbodiimide (abbreviated DCC), 0.2 g of 4- (N, N-diethylamino) pyridine and 40 g of methylene chloride was added dropwise with stirring for 1 hour. Further, the reaction was continued for 3 hours to complete the reaction. Next, 80%
After adding 10 g of formic acid and stirring for 1 hour, the insoluble matter was filtered off,
The filtrate was reprecipitated in 2.5 liters of methanol. After collecting the precipitate by filtration, the precipitate was dissolved again in 200 g of toluene, the insoluble matter was filtered off, and the filtrate was reprecipitated in 1 liter of methanol.
The precipitate was collected by filtration and dried. The yield of the obtained polymer is 7
At 0 g, the Mw was 4.5 × 10 ⁴ .

Production Examples 2-10 of Dispersion Stabilizing Resin (PB)
Resins (PB-2) to (PB-10) In Production Example 1 of dispersion stabilizing resin (PB), instead of octadecyl methacrylate and divinylbenzene, monomers and polyfunctional monomers shown in Table D below are used. Except for the above, the dispersion stabilizing resins were manufactured in exactly the same manner as in Production Example 1. Mw of each resin (PB) is 4 × 10 ^{4 to} 6 × 1
0 was ⁴ of range.

[0211]

[Table 4]

Production Examples 11 to 14 of Dispersion Stabilizing Resin (PB):
Resins (PB-11) to (PB-14) Production Example 1 of the dispersion stabilizing resin (PB) was the same as Production Example 1 except that the mercapto compound shown in Table E below was used in place of 3 g of thioglycolic acid. The same operation was performed to produce dispersion stabilizing resins (PB-11) to (PB-14).

[0213]

[Table 5]

Production Example 15 of Dispersion Stabilizing Resin (PB) Resin (PB-15) A mixed solution of 100 g of octadecyl methacrylate, 3 g of 2-mercaptoethanol, 4.5 g of divinylbenzene, 150 g of toluene and 50 g of ethanol was placed in a nitrogen stream. Was heated to a temperature of 60 ° C. A. I. B. N. Was added and reacted for 5 hours. I. B. N. Was added and reacted for 3 hours. I. B. N.
Was added and reacted for 3 hours.

Next, the reaction mixture was cooled to 25 ° C.
To this, 8 g of vinyl acetic acid was added, and D.I. C. C.
, A mixed solution of 0.4 g of 4- (N, N-diethylamino) pyridine and 30 g of methylene chloride was added dropwise over 1 hour, and the mixture was further stirred for 4 hours. Next, 30
A 5% ethanol solution of hydrogen chloride and 5 g of water were added, and the mixture was stirred as it was for 1 hour. After filtering off insolubles, the filtrate was reprecipitated in 2 liters of methanol. The precipitate was collected by filtration and dried. Mw of the obtained polymer was 5 × 10 ⁴ .

Production Examples of Dispersion Stabilizing Resin (PB) 16 to 23:
Resins (PB-16) to (PB-23) Production Example 15 of Production Example 15 of Dispersion Stabilizing Resin (PB) except that a polymerizable group-containing carboxylic acid compound shown in Table F below was used instead of vinyl acetic acid. Each dispersion stabilizing resin was manufactured in exactly the same manner as described above. The Mw of each of the obtained resins was about 5 × 10 ⁴ .

[0219]

[Table 6]

Production Example 24 of dispersion stabilizing resin (PB) Resin (PB-24) 100 g of octadecyl acrylate, 1.1 g of ethylene glycol diacrylate and tetrahydrofuran 2
While stirring under a nitrogen stream, 00 g of the mixed solution was heated at a temperature of 7 g.
Warmed to 0 ° C. 6 g of 4,4'-azobis (4-cyanopentanol) was added and reacted for 5 hours. Further, 1.0 g of the above azobis compound was added and reacted for 5 hours. The reaction mixture was cooled to a temperature of 20 ° C. in a water bath, and 3.2 g of pyridine and 1.0 g of 2,2′-methylenebis- (6-t-butyl-p-cresol) were added thereto, followed by stirring. To this mixed solution, 4.2 g of methacrylic acid chloride was added dropwise over 30 minutes so that the reaction temperature did not exceed 25 ° C. The mixture was stirred at a temperature of 20 ° C to 25 ° C for 4 hours. Next, the reaction product was reprecipitated in a mixture of 1.5 liter of methanol / 0.5 liter of water, and a white powder was collected by filtration and dried. With a yield of 82 g,
The Mw of the polymer was 7.5 × 10 ⁴ .

Production Example 1 of Resin Particles (L)
-1) Dispersion stabilizing resin (P-1) 12 g, vinyl acetate 89 g,
2- (N, N-diethylamino) ethyl crotonate 5
g, 6 g of 3-sulfopropylcrotonate, 10 g of ethanol and 230 g of Isopar H,
The mixture was heated to 70 ° C. while stirring under a nitrogen stream. 2,2'-azobis (isovaletonitrile) as a polymerization initiator
(Abbreviation AIVN) was added and reacted for 3 hours. Further, the initiator A. I. B. N. 0.8 g was added, and the mixture was heated to a temperature of 80 ° C. and reacted for 4 hours. Subsequently, the temperature was raised to 100 ° C. and the mixture was stirred for 2 hours to distill off unreacted monomers. After cooling, the mixture was passed through a 200-mesh nylon cloth, and the resulting white dispersion was 95% polymerized and had an average particle size of 0.45 μm.
Latex. The particle size was measured with CAPA-500 (manufactured by Horiba, Ltd.) (the same applies hereinafter).

A part of the white dispersion was centrifuged (rotation speed: 1 × 10 ⁴ rpm, rotation time: 1 hour), and the precipitated resin particles were collected and dried, and the mass average molecular weight of the resin particles was measured. When (Mw) and the glass transition point (Tg) were measured, Mw was 1 × 10 ⁵ and Tg was 40 ° C.

Production Examples 2 to 6 of Resin Particles (L): Resin Particles (L-2) to (L-6) Resin for stabilizing dispersion (P-1) used in Production Example 1 of resin particles (L) Was replaced with each other, and resin particles were produced in the same manner as in Production Example 1 except that the compounds shown in Table-G below were used. The polymerization rate of each of the obtained resin particles is 93 to
At 96%, the average particle size was in the range of 0.40 to 0.45 μm and the monodispersity was good. Further, Mw of each resin particle is 1 × 10 ^{5 to} 3 × 10 ⁵ , and Tg is 37 to 40 ° C.
Was in the range.

[0222]

[Table 7]

Production Example 1 of Resin Particles (LA) 12 g of Resin Particles (LA-1) Dispersion Stabilizing Resin (PA-1) and Isopar H2
82 g of the mixture was heated to a temperature of 70 ° C. while stirring under a nitrogen stream. 30 g of methyl methacrylate, 40 g of methyl acrylate, 2- (N, N-diethylamino)
6 g of ethyl methacrylate, 5 g of 6-sulfohexyl methacrylate and A.I. I. V. N. 1.5 g of the mixture was added dropwise over 1 hour, and the mixture was stirred for 2 hours. Next, A.
I. V. N. And heated to a temperature of 75 ° C.
Stir for an hour. I. B. N. 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 unreacted monomers. After cooling, the mixture was passed through a 200-mesh nylon cloth, and the obtained white dispersion was a latex having a conversion of 99% and an average particle size of 0.42 μm. The Mw of the resin particles was 2 × 10 ⁵ , and the Tg was 40 ° C.

Production Examples 2-4 of Resin Particles (LA): Resin Particles (LA-2)-(LA-4) In Production Example 1 of resin particles (LA), resins (PA-1) and Each of the resin particles was prepared in the same manner as in Production Example 1 except that the dispersion stabilizing resin (PA) and the monomer (B) shown in Table-H below were used instead of-(N, N-diethylamino) ethyl methacrylate. Manufactured. The average particle diameter of each of the obtained particles was a latex in the range of 0.40 to 0.45 μm. Mw of resin particles is 1 × 10 ^{5 to} 3 × 10
⁵ , Tg was in the range of 40-45 ° C.

[0225]

[Table 8]

Production Example 5 of Resin Particles (LA): Resin Particles (LA-5) 10 g of Dispersion Stabilizing Resin (PA-4) and Isopar G2
70 g of the mixture was heated to a temperature of 70 ° C. while stirring under a stream of nitrogen. To this, 15 g of methyl methacrylate, 30 g of methyl acrylate, 2- (N, N-dimethylamino)
7 g of ethyl methacrylate, 4 g of octadecyl acrylate and I. V. N. 1.5 g of the mixture, and 3
A mixture of 5 g of sulfopropyl methacrylate, 15 g of methyl methacrylate, 28 g of methyl acrylate and 10 g of ethanol was simultaneously added dropwise over 1 hour, and the mixture was stirred for 2 hours. Next, A. I. V. N. To 1.0
g, heated to a temperature of 75 ° C., and stirred for 3 hours.
A. I. B. N. 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, the mixture was passed through a nylon cloth of 200 mesh, and the obtained white dispersion was a latex having a conversion of 99% and an average particle size of 0.48 μm. M of resin particles
w was 2 × 10 ⁵ and Tg was 42 ° C.

Production Examples 6 to 13 of Resin Particles (LA): Resin Particles (LA-6) to (LA-13) Dispersion stabilizing resin (PA-4) used in Production Example 5 of resin particles (LA) Was replaced with each of the compounds shown in Table I below, and resin particles were produced in the same manner as in Production Example 5 above. The polymerization rate of each of the obtained resin particles is 9
8 to 100%, the average particle size was in the range of 0.45 to 0.50 μm, and the monodispersity was good. M for each resin particle
w was in the range of 1 × 10 ^{5 to} 3 × 10 ⁵ , and Tg was in the range of 40 to 43 ° C.

[0228]

[Table 9]

Production Example 1 of Resin Particles (LB) 8 g of Resin Particles (LB-1) Dispersion Stabilizing Resin (PB-1) and Isopar H29
0 g of the mixture was heated to a temperature of 70 ° C. while stirring under a nitrogen stream. 20 g of methyl methacrylate, 30 g of ethyl acrylate, 6 g of 2- (N, N-diethylamino) ethyl methacrylate, and I. V. N. , 1.
5 g of the mixture and a mixture of 15 g of methyl methacrylate, 25 g of methyl acrylate, 4 g of 4-sulfobutyl methacrylate and 10 g of ethanol were each added simultaneously at the same time.
The mixture was added dropwise over time, and the mixture was stirred for 2 hours. Next, A. I.
V. N. Was added, and the mixture was heated to a temperature of 75 ° C. and stirred for 3 hours. I. B. N. Was added, and the mixture was heated to a temperature of 80 ° C. and stirred for 3 hours. Then raise the temperature to 100
C. and stirred for 2 hours under a reduced pressure of 200 mmHg to distill off ethanol and unreacted monomers. After cooling, the mixture was passed through a nylon cloth of 200 mesh, and the obtained white dispersion was a latex having a conversion of 99% and an average particle size of 0.48 μm.
The Mw of the resin particles was 3 × 10 ⁵ , and the Tg was 40 ° C.

Production Example 2 of Resin Particles (LB): Resin Particles (LB-2) 8 g of Dispersion Stabilizing Resin (PB-12) and Isopar G2
80 g of the mixture was heated to 70 ° C. while stirring under a nitrogen stream. 15 g of methyl methacrylate, 30 g of methyl acrylate, 3- (N, N-diethylamino)
6 g of propyl methacrylate, 1 g of 2,3-dioctanoyloxypropyl methacrylate and I. V.
N. 2.0 g of a mixture of methyl methacrylate 15
g, 35 g of methyl acrylate, 3 g of 2-sulfoethyl methacrylate, and 15 g of ethanol were each added dropwise at the same time for 1 hour, and the mixture was stirred for 2 hours.
Next, A. I. V. N. Was added, and the mixture was heated to a temperature of 75 ° C. and stirred for 3 hours. I. B. N. To 0.8
g 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, the mixture was passed through a 200-mesh nylon cloth, and the resulting white dispersion was a latex having a conversion of 99% and an average particle size of 0.45 μm. The Mw of the resin particles was 2 × 10 ⁵ , and the Tg was 41 ° C.

Production Examples 3 to 12 of Resin Particles (LB): Resin Particles (LB-3) to (LB-12) In Production Example 2 of resin particles (LB), resins (PB-12) and Production was carried out in the same manner as in Production Example 2 except that each of the compounds shown in Table J below was used instead of 2,3-dioctanoyloxypropyl methacrylate. The polymerization rate of each of the obtained particles is 97 to 99%, and the average particle size is 0.1%.
The monodispersity was good within the range of 45 to 0.50 μm. The Mw of the resin particles is 9 × 10 ⁴ to 4 × 10 ⁵ ,
Tg was in the range of 40-43 ° C.

[0232]

[Table 10]

Production Examples 13 to 17 of Resin Particles (LB): Resin Particles (LB-13) to (LB-17) In Production Example 2 of resin particles (LB), 3- (N, N-
Instead of 6 g of diethylamino) propyl methacrylate, 0.027 mol of the monomer (B) shown in the following Table-K was used, and instead of 2-sulfoethyl methacrylate, the following table was used.
Each particle was produced in the same manner as in Production Example 2 except that 0.02 mol of the K monomer (C) was used. The average particle diameter of each of the obtained particles was latex in the range of 0.35 to 0.45 μm. Mw for resin particles is 9 × 10 ⁴ to 2 × 1
0 ⁵ , Tg was in the range of 40 to 48 ° C.

[0234]

[Table 11]

Production Example of Comparative Resin Particles 1: Resin Particles (L
R-1) In the same manner as in Production Example 1 except that 95 g of vinyl acetate and 5 g of 2- (N, N-diethylamino) ethylcrotonate were used as monomers to be polymerized in Production Example 1 of resin particles (L). To produce resin particles. The obtained white dispersion had a conversion of 96% and an average particle size of 0.40 μm. The Mw of the resin particles was 2 × 10 ⁵ , and the Tg was 37 ° C.

Example 1 <Preparation of a lithographic printing plate precursor> A composition having the following contents was added to a paint shaker (Toyo Seiki Co., Ltd.) together with glass beads.
And dispersed for 60 minutes, and then the glass beads were separated by filtration to obtain a dispersion.

・ Gelatin 8 g ・ Alkoxysilane-modified polyvinyl alcohol R1130 (manufactured by Kuraray Co., Ltd.) 4 g ・ Silica: Thylysia 310 (manufactured by Fuji Silysia Chemical Ltd.) 8 g ・ Colloidal silica 20% solution: Snowtech C 38 g (Nissan Chemical Industrial Co., Ltd.)-Fluorinated alkyl ester FC430 (manufactured by 3M) 0.8 g-Hardening compound 0.24 g CH ₂ = CHSO ₂ CH ₂ CONH (CH ₂ ) ₃ NHCOCH ₂ SO ₂ CH = CH _2. 54 g of water

An ELP-1X master known as an electrophotographic planographic printing plate precursor (Fuji Photo Film Co., Ltd.)
The above composition was coated on the support using a wire bar and dried at 100 ° C. for 10 minutes to form an image receiving layer having a coating amount of 8 g / m ^2. I got The surface smoothness of the obtained image-receiving layer was measured using a Beck smoothness tester (manufactured by Kumagai Riko Co., Ltd.) and the air volume was 10 ml.
The smoothness (sec / 10ml) was measured under the conditions of
(Sec / 10 ml). Further, 2 μl of distilled water was placed on the surface of the image receiving layer, and the surface contact angle (degree) after 30 seconds was measured using a surface contact meter CA-D (manufactured by Kyowa Interface Science Co., Ltd.). The contact angle of the surface of the image receiving layer with water was 0 degree.

<Preparation of oil-based ink (IK-1)> 10 g of polydodecyl methacrylate, 10 g of alkali blue
And 30 g of Shellsol 71 were placed in a paint shaker (manufactured by Toyo Seiki Co., Ltd.) together with 30 g of glass beads, dispersed for 4 hours, and the glass beads were filtered off to obtain a fine blue dispersion. 50 g (as a solid content) of the resin particles (L-1) produced in Production Example 1 of the resin particles (L), 18 g of the alkali blue dispersion, and 0.1 g of cobalt octenoate.
A blue oil-based ink was prepared by diluting 15 g to 1 liter of Isopar E.

Comparative Example A The procedure of Example 1 was repeated, except that the oil-based ink (IKR-1) was replaced with the oil-based ink (IKR-1) described below. <Preparation of Comparative Oil-Based Ink (IKR-1)> In the preparation of the oil-based ink (IK-1), except that the comparative resin particles (LR-1) were used instead of the resin particles (L-1), inks were used. It was prepared in the same manner as (IK-1).

The charging characteristics, ejection characteristics,
The shape of print dots, image reproducibility, printing durability, etc. were examined, and the results are shown in Table-L.

[0242]

[Table 12]

The evaluation items described in Table-L were performed according to the following contents. Note 1) Charging characteristics-AC electric conductivity AC electric conductivity (pS / cm) was measured as the amount of charge of the ink. The AC electrical conductivity of the ink was measured with an LCR meter (AG-4311, manufactured by Ando Electric Co., Ltd.). At the time of measurement, a liquid electrode placed in a self-made aluminum shield box was filled with 2.3 ml of the ink to be measured via a test lead (AG-4912, manufactured by Ando Electric Co., Ltd.) using an LCR meter. (LP- manufactured by Kawaguchi Electric Co., Ltd.)
05, electrode constant 198), conductance was measured at an applied voltage of 5 V and a measurement frequency of 1 kHz, and the value was converted to an electric conductivity by dividing the value by the electrode constant. In the measurement, the measurement parameters of the LCR meter were set to capacitance, and the circuit mode was set to parallel mode.

Particle Charge Ratio Indicates the ratio of the amount of charge of the dispersed particles in the ink.

[0245]

(Equation 1)

Here, the charge amount of the supernatant is determined by measuring the AC electrical conductivity of the transparent liquid obtained by sedimenting the ink by centrifugation (conditions: 1 × 10 ⁴ rpm, 1 hour). Represent.

Further, the conditions I and II show changes in the time-lapse state after the ink production, and the condition I means that the ink obtained by mixing all the components was allowed to stand naturally for one week (normal temperature, normal humidity). )
(Fresh product), while condition II is
The fresh product was stored under high-temperature and high-humidity (40 ° C., 85% RH) conditions for 2 weeks and was forcibly aged (aged product).

Note 2) Dischargeability Dischargeability was measured by an apparatus using an injection needle as shown in FIG. The injection needle is made of stainless steel and has an inner diameter of 36.
0 μm, an outer diameter of 615 μm, a cutting angle at the tip of 19 °, a radius of curvature of 13 μm, and an ink tank 36 at the tip of the needle.
Is always supplied from the inside of the needle by the liquid sending pump 35, and the excess ink is naturally transmitted to the needle surface and collected in the waste liquid tank 37. The ink flow rate at this time is 0.75
ml / min. This injection needle is arranged at a distance of 300 μm from the surface of the plate material as the recording medium 32 mounted on the drum-shaped counter electrode 31, and a power supply 33 supplies a bias voltage of 700 V, a discharge voltage of 800 V, and a pulse voltage of 100 μSec width of 5 μm. Printing was performed by superimposing and applying at a frequency of 0.0 kHz. The polarity of the bias and the pulse voltage was determined so that the ink was repelled from the injection needle. The ejection rate was calculated from the number of dots actually printed with respect to the number of applied pulses (%). Conditions I and II are the same as in Note 1).

Note 3) Shape of Print Dots and Film Thickness The film thickness of the print dots of the sample subjected to the discharge test was measured from a scanning electron microscope (SEM) photograph in the discharge property evaluation item. The larger the film thickness is, the more concentrated the particles in the ink are ejected.

Shape Similarly, using the above sample, the presence or absence of dot bleeding, distortion, and the like was examined by optical microscope and SEM photograph observation.

Note 4) Image reproducibility Using the lithographic printing plate precursor prepared as described above, a Servo Proter DA8400 manufactured by Graphtec Co., Ltd., capable of drawing the output of a personal computer, was modified, and the Ben Plotter part shown in FIG. 2 was used. The ink ejection head was mounted, and printing was performed on the lithographic printing original plate placed on the counter electrode spaced at a distance of 500 μm using the above oil-based ink to make a plate. At this time, printing was performed at a bias voltage of 650 V, an ejection voltage of 700 V,
The test was performed under the condition that a pulse voltage having a width of 0 μsec and a frequency of 2.0 kHz were used. Next, RICOFUUSER model 5
Using 92 (manufactured by Ricoh Co., Ltd.), the surface temperature of the ink image was adjusted to 95 ° C. and heated for 20 seconds to sufficiently fix the image area. A copy image of the obtained plate (ie, printing plate) was visually observed at a magnification of 200 times with an optical microscope.

Note 5) Printing durability Using a printing plate obtained according to the method of Note 4), using a solution obtained by diluting SLM-OD (manufactured by Mitsubishi Paper Mills) 30 times with water as immersion water. Oliver 94 type (manufactured by Sakurai Seisakusho Co., Ltd.) was used as a printing machine, and printing was performed using black ink for offset printing. The number of prints on which a clear image with no background stains and no missing fine lines or characters is obtained is represented as printing durability.

As shown in Table-L, Example 1 showed a good result in the charging characteristics, and the change was small even in the aged sample, which was within a range in which there was no practical problem. On the other hand, Comparative Example A had a small charge amount and a low charge fraction of particles. In addition, due to aging, the change in chargeability is large,
In particular, the charge fraction of the particles was significantly reduced.

Next, from the results of the ejection property and the shape of the dots on the printed plate material, Example 1 showed good performance in both the fresh product (condition I) and the aging product (condition II). . That is, in Comparative Example A, the film thickness was thin, and the dot shape was also blurred. Only the image of Example 1 showed good performance in both the fresh product and the aged product.

Further, when printing was performed using this printing plate, the printing durability of Example 1 was 3,000 or more. In Comparative Example A, the image portion was missing from printing and was unusable, and the formed image portion was lost after printing about 1,000 sheets.

From the above results, it can be seen that the ink of the present invention has a large charge amount of the whole ink even if the storage state changes and the charge fraction to the particles is as high as 88% or more. Good properties, no aggregation / precipitation. By these things, in the ink discharge of the electrostatic ink jet system, the ink meniscus is stably formed on the discharge electrode, and the charged particles in the ink are also electrophoresed quickly under voltage suppression, and the particles are concentrated. In this state, printing is performed on a printing original plate that is an ink receiving material. Therefore, the print dots on the plate material have a thick film thickness of 1.3 μm, and the dots do not bleed in a circular shape, and no generation of distortion or the like is observed. Furthermore, when actually printing as a printing plate, since the thickness of the image portion is sufficient,
The printing durability was as good as 3,000 sheets or more.

On the other hand, in Comparative Example A, since the charge amount of the ink was small and the charge fraction of the particles was as low as 70% or less, both the ejection property and the concentration property of the particles were insufficient, and the plate-making image formed was unsatisfactory. Was something. Further, the chargeability deteriorated with time. From the above, only the oil-based ink of the present invention showed stable and good performance over time.

Examples 2 to 15 In Example 1, instead of 50 g of the resin particles (L-1) in the oil-based ink (IK-1), 50 g of each of the resin particles shown in the following Table-M (as solid content) was used. Otherwise, each oil-based ink was prepared in the same manner as in the oil-based ink (IK-1) and evaluated in the same manner as in Example 1.

[0259]

[Table 13]

Each oil-based ink (IK-2) to (IK-15)
Show the same charging characteristics as the oil-based ink (IK-1), and the sample under condition II has an AC electric conductivity of 330 to 380 (pS / cm) and a charged fraction of particles of 88.
９５95%. Actual dischargeability, dot shape,
Both image reproducibility and printing durability were equal to or better than those of Example 1. Further, even with the lapse of time, no aggregation or precipitation of particles was observed, and the dispersibility was good.

Example 16 <Preparation of a lithographic printing original plate> A composition having the following contents was put together with glass beads in a paint shaker and dispersed for 80 minutes. Then, the glass beads were separated by filtration to obtain a dispersion.

• Silica: 40 g of Sylysia 445 (manufactured by Fuji Silysia Chemical Ltd.) • 20% colloidal silica solution: 200 g of Snowtec C (manufactured by Nissan Chemical Industries, Ltd.) • 40 g of clay dispersion 40 g • polyvinyl alcohol: PVA -117, 10% solution 120 g (manufactured by Kuraray Co., Ltd.)-Melamine resin 2.0 g-Ammonium chloride 0.2 g-Water 50 g

An ELP-2X type master known as an electrophotographic lithographic printing plate precursor (Fuji Photo Film Co., Ltd.)
The above composition was coated on the support using a wire bar and heated at 110 ° C. for 10 minutes to form an image receiving layer having a coating amount of 6 g / m ^2. I got The surface smoothness of the obtained image receiving layer was 300 (sec / 10 ml) in Beck's smoothness, and the contact angle of the surface with water was 0 degree. This printing original plate was made in the same manner as in Example 1. However, the oil-based ink (IK-1) used in Example 1
Was replaced by an oil-based ink (IK-16) having the following content.

<Preparation of Oil-Based Ink (IK-16)> The resin particles (LB) obtained in Production Example 1 of the resin particles (LB) were obtained.
-1) A mixture of 50 g (as solid content) and 3 g of Victoria Blue B was heated to a temperature of 100 ° C., and heated and stirred for 3 hours. After cooling to room temperature, the mixture was passed through a 200-mesh nylon cloth to remove the remaining dye.
A 48 μm blue resin dispersion was obtained. 25 g of the above-mentioned blue resin dispersion (as solid content) and 0.15 g of cobalt naphthenate as a charge control agent were diluted in a mixed solution of hexamethyldisiloxane / Isoper G (3/2 mass ratio) to make a total volume of 1 liter. Thus, a blue oil-based ink was prepared.

The properties of the obtained ink were measured in the same manner as in Example 1, and the results as shown in Table N below were obtained. The chargeability, dischargeability, and dot shape were good even with the lapse of time.

[0266]

[Table 14]

Next, after making a plate in the same manner as in Example 1,
Printing was done. The obtained printed matter had a clear image quality with no stain on the non-image area, as in the printed matter of Example 1, and had excellent printing durability of 10,000 sheets or more. In addition, when the performance was examined using an ink (condition II) that had been stored for a long time under high temperature and high humidity, no aggregation or precipitation of particles was observed and the dispersibility was good, and the results of actual plate making and printing were equivalent to fresh products. Was a good result.

Examples 17 to 32 Plate-making was performed in the same manner as in Example 16, except that the oil-based ink (IK-16) was replaced with each of the oil-based inks shown in Table O below. The oil-based ink used was the same as the oil-based ink (IK-16) in Example 16 except for the resin particles (LB-1) used in Table 16 below.
It was prepared in the same manner except that 50 g (as a solid content) of each resin particle shown in O was used.

[0269]

[Table 15]

When the characteristics of the ink were evaluated in the same manner as in Example 16, the AC electric conductivity of the ink was 48 for each ink.
0 to 530 (pS / cm), and the charged fraction of particles is 90 to 9
It was in the range of 5%. The image reproducibility was excellent, showing exactly the same performance as that of Example 16. Further, when printing was performed as a printing plate, all plates exhibited a printing durability of 10,000 sheets or more. Further, with respect to the aged ink (Condition II), Example 16 was used.
The image reproducibility and printing durability were equivalent to those of the fresh product.

Example 33 <Preparation of Water-Resistant Support> Weighing 100 g / m ² as a substrate
Using a high-quality paper, a coating for underlayer having the following composition was applied to one surface of the substrate using a wire bar to provide an underlayer with a dry coating amount of 10 g / m ² . The smoothness of the under layer surface was 150 seconds / 10 ml, and the smoothness was adjusted to 1500 (second / 10 ml) by calendering.

<Coating for Under Layer>-10 parts by mass of silica gel-92 parts by mass of SBR latex (50% by mass aqueous dispersion, Tg: 25 ° C)-110 parts by mass of clay (45% by mass aqueous dispersion)-Melamine (80 5% by mass ・ Water 191 parts by mass

Further, a coating material for a back coat having the following composition was applied to the other surface of the substrate using a wire bar to provide a back coat layer having a dry coating amount of 12 g / m ² . Calendar processing was performed by setting calendar conditions so that the smoothness was about 50 (seconds / 10 ml).

<Coating for Back Coat Layer> 200 parts kaolin (50% aqueous dispersion) 60 parts aqueous polyvinyl alcohol solution (10%) 100 parts SBR latex (solid content 49%, Tg: 0 ° C.) 100 parts melamine resin Initial condensate 5 parts (solid content 80%, Sumiretz Resin SR-613)

<Preparation of a lithographic printing plate precursor> Zinc oxide 100
g, 16 g of binder resin (B-1) having the following structure, 2 g of binder resin (B-2), 0.15 g of benzoic acid, and 1 part of toluene
55 g of the mixture was dispersed at a rotation speed of 6 × 10 ³ rpm for 8 minutes using a wet disperser homogenizer (manufactured by Nippon Seiki Co., Ltd.).

[0276]

Embedded image

This dispersion was coated on the above water-resistant support using a wire bar so that the coating amount was 10 g / m ² .
By coating and drying, a lithographic printing original plate having a surface smoothness of 250 (seconds / 10 ml) was prepared. Surface contact angle with water is 10
It was twice.

<Preparation of Oil-Based Ink (IK-33)> 10 g of dispersion stabilizing resin (P-1) and black pigment (Microlith Bl)
ack CT, Ciba-Geigy) 10 g and Isopar E,
113 g was placed in a paint shaker together with the glass beads and dispersed for 6 hours, and the glass beads were separated by filtration to obtain a black dispersion. 60 g (as solid content) of resin particles (LB-12) produced in Production Example 12 of resin particles (LB), 66 g of the above black dispersion and 0.18 g of zirconium naphthenate
Was diluted with hexamethyldisiloxane so that the total amount became 1 liter, to prepare a black oil-based ink (IK-33). The AC conductivity of the obtained ink was 480 (pS /
cm), and the charged fraction of the particles was 92%.

The printing original plate and oil-based ink (IK-3)
A plate was made in the same manner as in Example 1, except that 3) was used, to obtain a plate having a clear image without any loss of fine lines and characters. The thickness of the dot was 2.3 μm, and it was a good circular dot without bleeding or distortion. The sample under condition II shown in Example 1 also had good dispersibility and a small change in chargeability.

[0280] Next, with respect to the plate-making products prepared using the oily ink of the fresh product and the aging product, a desensitizing solution (ELP-E2, manufactured by Fuji Photo Film Co., Ltd.) was applied to a fully automatic printing machine (AM). -2850, put in an etcher part of ASM Co., Ltd., and as a fountain solution, a desensitizing solution (E
A solution obtained by diluting LP-E2) four times with distilled water was placed in a fountain solution tray, and printing was performed using black ink for offset printing. As a result, more than 3,000 printed images with clear images free of background stains were obtained.

Examples 34 to 36 Plate making was performed in the same manner as in Example 16 except that the oil-based ink (IK-16) was replaced with each of the oil-based inks shown in Table P below. The oil-based ink used was replaced with the resin particles (LB-1) used in the oil-based ink (IK-16) in Example 16 by using the following Table-P
Was prepared in the same manner except that 50 g (as a solid content) of each resin particle shown in (1) was used.

[0282]

[Table 16]

Oily inks (IK-34) to (IK-3)
Table-P shows the charging characteristics, ejection properties, and dot shapes under the condition II of 6). Very good results were obtained in the same manner as in Example 16 in the sample aged as in the case of the fresh product. As a result of actual printing, printing durability of 10,000 sheets or more was shown.

[0284]

By using the oil-based ink of the present invention, it is possible to form an image excellent in ink ejection stability, clear image forming property and image strength, and to obtain a clear image in an electrostatic ink jet recording system. A printing plate capable of printing a large number of printed matters can be provided.
Further, according to the oil-based ink for electrostatic ink jet of the present invention, the dispersibility of the dispersed particles and the storage stability are excellent, the ink is not clogged in the ink supply path, and the ejection of the ink is stabilized.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an example of an apparatus system to which the oil-based ink of the present invention can be applied.

FIG. 2 is a diagram showing a part of a head of an ink jet recording apparatus to which the oil-based ink of the present invention can be applied.

FIG. 3 is a diagram in which a meniscus regulating plate is removed from the head shown in FIG. 2;

FIG. 4 is a view showing a discharge test apparatus used in the examples.

[Explanation of symbols]

 1 Inkjet recording apparatus 2 Lithographic printing master (master) 3 Computer 4 Bus 10 Inkjet recording head 13 Inkjet recording head 14 Head body 15, 16 Meniscus regulating plate 17 Ejection electrode 18 Ink groove 19, 21 Partition 20, 20 'Ejection Part 22 Tip part 31 Drum-shaped counter electrode 32 Recording medium 33 Power supply 34 Recording head 35 Liquid feed pump 36 Ink tank 37 Waste liquid tank

Claims (4)

[Claims] 1. An oil ink for electrostatic inkjet comprising at least charged resin particles dispersed in a non-aqueous carrier liquid having an electric resistance of not less than 10 ⁹ Ω · cm and a dielectric constant of not more than 3.5. A resin particle which is soluble in a non-aqueous solvent and which contains at least one monofunctional monomer (A) which is insoluble by polymerization, containing an amino group represented by the general formula (I). At least one monofunctional monomer (B) copolymerizable with the monomer (A), containing -SO ₃ H and / or -SO ₂ H groups and copolymerizable with the monomer (A) A polymer containing at least one monofunctional monomer (C) and a component represented by the following general formula (II), wherein a part of the main chain of the polymer is cross-linked, Contains at least one dispersion stabilizing resin (P) that is soluble in an aqueous solvent Electrostatic inkjet oil green ink, wherein the solution is a copolymer resin particles obtained by the polymerizing granulation. Embedded image 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 bonded together with a nitrogen atom. A ring may be formed. Embedded image In the general formula (II), V ⁰ is -COO-, -OCO-,-
(CH ₂ ) _r COO-,-(CH ₂ ) _r OCO-, -O- or (Where X is a mere bond, -O-, -OCO- or -C
OO-). r represents an integer of 1 to 12. L
Represents an alkyl group having 8 to 32 carbon atoms or an alkyl group having 8 to 32 carbon atoms.
Represents an alkenyl group. b ¹ and b ² may be the same or different, and each represents a hydrogen atom, a halogen atom, a cyano group, a hydrocarbon group having 1 to 7 carbon atoms, —COO-D ¹ ,
Or an -COO-D ¹ via a hydrocarbon group (wherein by D ¹ represents a hydrogen atom or a hydrocarbon group having 1 to 22 carbon atoms). 2. A dispersion stabilizing resin (P) is provided at one end of at least one polymer main chain with -PO ₃ H ₂ , -SO ₃ H,-
COOH, -P (= O) ( OH) R 11 [wherein R ¹¹ represents a hydrocarbon group or -OR ^12, (R ¹² represents a hydrocarbon group)
The representative], -OH, formyl group, -CONR ¹³ R ^14, -
SO ₂ R ¹³ R ¹⁴ wherein R ¹³ and R ¹⁴ may be the same or different and each represent a hydrogen atom or a hydrocarbon group], a cyclic acid anhydride-containing group, and at least one selected from an amino group The oil-based ink for electrostatic ink jet according to claim 1, further comprising a polar group. 3. A dispersion stabilizing resin (P) comprising a polymerizable double bond group represented by the following general formula (III) bonded to one end of at least one polymer main chain. The oil-based ink for electrostatic inkjet according to claim 1. Embedded image In the general formula (III), V ¹ represents -COO-, -OCO-,-
_{(CH 2) t COO -,} - (CH 2) t OCO -, - O -, -
SO _2- , -CONHCOO-, -CONHCONH
—, —CON (D ² ) —, —SON (D ² ) — or a phenylene group (where D ² is a hydrogen atom or a carbon atom
To 22 and t represents an integer of 1 to 4). c ¹ and c ² may be the same or different from each other, and have the same meanings as b ¹ and b ² in the formula (III). 4. The dispersed resin particles further comprise a monomer
One of the following general formula (IV) copolymerizable with (A)
Solution containing at least one functional monomer (D)
Copolymerized resin particles obtained by granulation
The electrostatic device according to any one of claims 1 to 3, wherein
Oil-based ink for inkjet. Embedded imageIn the general formula (IV), U¹Is -COO-, -CONH-,-
CON (E^Two)-(Where E^TwoIs an aliphatic group or one of the following
Represents a substituent represented by the general formula (IVa)), -OCO-,
-CONHCOO-, -CH_TwoCOO-,-(CH_Two)_S
OCO-, (where s represents an integer of 1 to 4), -O
-Or -C₆H_FourRepresents -COO-. c¹And c^TwoIs
Same or different, hydrogen atom, alkyl group, halo
Gen atom, cyano group, -COO-E^ThreeOr -CH_TwoCO
OE^Three(Where E^ThreeRepresents an aliphatic group). E¹Is
An aliphatic group having 8 or more carbon atoms or a total of 8 or more atoms (however,
Excluding hydrogen atoms that are directly bonded to carbon and nitrogen atoms)
Represents a substituent represented by the following general formula (IVa). General formula (IVa)-(A¹-B¹)_m-(A^Two-B^Two)_n-R^{twenty one} In the general formula (IVa), R^{twenty one}Is a hydrogen atom or a carbon number of 1 to 1
8 represents an aliphatic group. B¹And B^TwoAre the same or different
Thus, -O-, -S-, -CO-, -CO _Two−, −
OCO-, -SO_Two-, -N (R^{twenty two})-, -CON (R
^{twenty two})-, -N (R^{twenty two}) CO-, -N (R^{twenty two}) SO_Two−,
-SO_TwoN (R^{twenty two})-, -NHCO_Two-Or -NHCO
NH- (where R^{twenty two}Is the above R^{twenty one}Synonymous with
). A¹And A^TwoAre the same or different,
A group represented by the formula (IVb) and a hydrocarbon having 1 to 18 carbon atoms:
Represents at least one group selected from groups. m
And n are the same or different and each represents an integer of 0 to 4
Represent. However, the sum of m and n does not become zero. Embedded imageIn the general formula (IVb), B^ThreeAnd B^FourAre the same or different
And the above B¹, B^TwoIs synonymous with A^FourHas 1 to 18 carbon atoms
A hydrocarbon group of R^{twenty three}Is R^{twenty one}Is synonymous with p
Represents an integer of 0 to 4.