JP2640288B2 - Non-aqueous dispersant and liquid developer for electrostatography - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a dispersant in an electrostatographic liquid developer, a printing ink, a paint and the like, and an electrostatographic image produced by using the dispersant and having improved dispersion characteristics. The present invention relates to a liquid developer.

"Prior art" Electrostatic liquid developers, printing inks, paints, and the like are pigments and dyes, and a colorant or fixing resin in which the pigment or dye is coated with a fixing resin is finely dispersed and stably dispersed. Is required. In particular, in a liquid developer for electrophotography, a colorant called a toner dispersed in a non-aqueous solvent having a high electrical resistance affects the quality of a developed image, so that good toner dispersibility is required.

Generally, in an electrostatographic process, there are a dry developing method and a liquid developing method as a method of visualizing a formed electrostatic latent image. The liquid developing method is capable of making toner particles finer than the dry developing method, and is an excellent method for faithfully reproducing fine images and halftones.

In general, a liquid developer for electrostatography is a coloring agent such as various kinds of pigments and dyes typified by carbon black, a coating agent for adjusting or fixing a charge by adsorbing or coating on the coloring agent, and dispersibility in toner particles. Dispersant to be applied, charge control agent to control polarity and amount of charge of toner particles, and volume resistivity of 10 ⁹ Ωc
It is composed of a non-aqueous solvent carrier liquid having a high electrical resistance of at least m and a dielectric constant of 3 or less. Pigments and dyes may not be used for those requiring only ink adhesion to a toner image, such as printing plates, and those requiring only resistive properties to an etching solution at the time of preparing a printing plate. Liquid developers, printing inks, and paints are generally produced by the following method. Pigment or dye, fixing resin, pigment photographic dye coated with fixing resin is pulverized as it is or dry, and wet dispersion such as ball mill, paint shaker, sand mill, etc. with high resistance non-aqueous solvent in which dispersant is dissolved Disperse to the desired size using a machine to make a concentrated dispersion. The concentrated dispersion is used as it is or after being diluted with a solvent. In the case of a liquid developer, this concentrated dispersion is added to a carrier liquid containing a charge control agent to obtain a liquid developer having a positive or negative polarity.

Non-aqueous dispersant for wet dispersion, as described above, using a wet disperser such as a ball mill, paint shaker, sand mill, for the purpose of dispersing fine particles when dispersing a pigment or resin in a non-aqueous solvent. Means the compound used.

Examples of the non-aqueous dispersant used herein include oils and fats soluble in the carrier liquid, long-chain carboxylic acids such as oleic acid, oil-modified alkyd resins, abietic acid esters,
Homopolymers of long-chain alkyl acrylates and methacrylates such as ethylhexyl (meth) acrylate and stearyl (meth) acrylate, and random copolymers thereof with styrene, vinyltoluene, methyl (meth) acrylate and ethyl (meth) acrylate It has been commonly used.

However, these dispersants can achieve a certain degree of dispersibility and dispersion stability after dispersion when pigments and dyes are used alone.However, coloring agents such as pigments and dyes coated with a fixing resin and the fixing resin itself are used. When dispersing is attempted, the dispersibility is remarkably reduced. In some cases, the resin of the dispersant and the resin of the coating agent may unite to form an aggregate or a lump. A liquid developer used for a printing plate produced by eluting a non-image area with an etching solution requires resist resistance. Therefore, generally, a hard-dispersing fixing resin is used. It is impossible to disperse.

In Japanese Patent Publication No. 59-37826, a vinyl copolymer containing a morpholino group is filed as a dispersant for a liquid developer for electrostatography. The dispersion effect is insufficient for dispersion. In JP-A-60-10263, a block copolymer of styrene and a long-chain alkyl methacrylate is filed as a pigment dispersant. Here, only the dispersing effect of the pigment alone is described because a fixing effect is exerted on the block copolymer itself. Therefore, the dispersing effect of the pigment coated with the fixing resin is unknown. Also, the synthesis of these block copolymers is complicated. JP-A-57-128350 has filed an application for a graft copolymer of a soluble vinyl copolymer and an insoluble vinyl copolymer via a urethane bond, which is disclosed as a dispersant for a pigment or dye alone. No mention is made of the dispersing effect of the colorant coated with the fixing resin.

In JP-B-56-10619 and JP-B-60-18985, a vinyl polymer and glycidyl methacrylate for imparting a graft active site are copolymerized to synthesize a trunk polymer, which is esterified with acrylic acid, and then other vinyl monomers are synthesized. A liquid developer using a graft copolymer obtained by copolymerization is shown. Although the graft copolymer shown here functions as toner particles by itself, it is disclosed as being used in combination with a pigment and having a dispersing action on the pigment. Further, in JP-B-52-3306 and JP-B-57-12985, after a copolymer of a vinyl monomer and glycidyl methacrylate is esterified with an unsaturated carboxylic acid,
1 shows a graft copolymer obtained by copolymerizing one or more vinyl monomers. These patents disclose the dispersing effect of the graft copolymer on the pigment, but do not mention the dispersing effect on the colorant coated with the fixing resin and the fixing resin itself. It is also known that the graft copolymer thus obtained often forms a gel due to difficulty in controlling the crosslinking reaction (Japanese Patent Publication No. 1-24302, JP-A-58-150970). Further, it is also known that the produced homopolymer is eluted into the carrier liquid over time to lower the dispersion stability and the charge stability (JP-A-59-34540).

In general, a graft copolymer is generally obtained by first polymerizing a trunk portion in which a plurality of graft active sites are introduced in one molecule, then bonding a portion to be a graft (branch) to the active site of the trunk portion, and then forming a branch portion. It polymerizes.

This method has problems such as difficulty in controlling the polymerization due to the complicated reaction, causing a cross-linking reaction to give a gelled product, formation of a homopolymer having a branched portion, and poor reproducibility of synthesis. It is also known that when a large number of graft active sites are introduced, gelation is more likely to occur.
It is considered that this is because the prepolymer into which a plurality of graft active sites have been introduced is a so-called polyfunctional monomer having a plurality of polymerizable sites in one molecule, and thus is easily gelled by a crosslinking reaction. When these graft copolymers are used as a dispersant, poor reproducibility of dispersion has been obtained due to the problems described above.

As a dispersant, a styrene / butadiene copolymer is also known. However, a dispersion obtained by dispersing the styrene / butadiene copolymer may sometimes cause gelation during long-term storage due to double bonds remaining in butadiene. May give.

[Problems to be Solved by the Invention] Synthesize an effective dispersant and a dispersant described above for dispersing a colorant coated with a pigment, a dye and a fixing resin, and further a fixing resin itself by a wet dispersion method. No solution to the above problem has yet been found.

"Object of the Invention" A first object of the present invention is to provide a non-aqueous dispersion for wet dispersion in which any of a pigment or dye, a pigment or dye coated with a fixing resin, and a fixing resin can be dispersed by wet dispersion. To provide an agent.

A second object of the present invention is to provide a graft copolymer for dispersion which does not have a complicated reaction and has few by-products such as gels and homopolymers.

A third object of the present invention is to provide an electrostatographic liquid developer having improved dispersing properties provided by the above dispersant.

A fourth object of the present invention is to provide a printing plate liquid developer having excellent resist properties to an etching solution and having improved dispersion characteristics.

A fifth object of the present invention is to provide a liquid developer for electrostatic photography which has good re-dispersibility and improved stability over time and has good image reproducibility.

`` Means for solving the problem '' An object of the present invention is to provide a non-aqueous dispersant for wet dispersion soluble in a non-aqueous solvent having a volume resistivity of 10 ⁹ Ωcm or more and a dielectric constant of 3 or less and the non-aqueous solvent carrier liquid, At least, a pigment or dye, a resin insoluble or swellable in the carrier liquid, a liquid developer for electrophotography containing at least one of a dye or pigment coated with the resin, a dispersant and a charge control agent, A dispersant is polymerized at only one end of a polymer main chain containing at least one of the polymer components represented by the following general formula (IIa) or (IIb): Weight average molecular weight 1 × 10 ³ -4 formed by bonding a reactive double bond group
This was achieved by forming a graft copolymer comprising × 10 ⁴ monofunctional macromonomer (M) and at least one monomer represented by the following general formula (III).

General formula (I) Wherein (I), V is _{-COO -, - OCO-, CH 2} l OCO
_{-, CH 2 l COO -,} - O -, - CONHCOO -, - CONHCO
_{-, - SO 2 -, -} CO-, Or Represents

Here, Z ₁ represents a hydrogen atom or a hydrocarbon group, and 1 represents an integer of 1 to 3.

a ₁ and a ₂ may be the same or different, and each represents a hydrogen atom, a halogen atom, a cyano group, a hydrocarbon group, -CO
O—Z ₂ or —COO—Z ₂ via a hydrocarbon (Z ₂ represents a hydrogen atom or a hydrocarbon group which may be substituted).

General formula (IIa) General formula (IIb) In formula (IIa), X ₀ has the same content as V in formula (I).

Q ₀ represents an aliphatic group having 1 to 22 carbon atoms or an aromatic group having 6 to 12 carbon atoms.

Q is -CN or Represents Here, Y represents a hydrogen atom, a halogen atom, an alkoxy group or —COOZ ₃ (Z ₃ represents an alkyl group, an aralkyl group or an aryl group).

b ₁ and b ₂ may be the same or different from each other, and have the formula (I)
It represents the same contents as a ₁ and a ₂ in the table.

General formula (III) In formula (III), X ₁ has the same content as X ₀ in formula (IIa), and Q ₁ has the same content as Q ₀ in formula (IIa) and a hydrogen atom. d ₁ and d ₂ may be the same or different from each other and represent the same contents as a ₁ and a ₂ in the formula (I).

However, the macromonomer (M) represented by the general formula (II)
In the component and the monomer component represented by the general formula (III), at least _one of Q ₀ and Q ₁ represents an aliphatic group having 8 to 22 carbon atoms.

As the dispersant of the present invention, -PO at one end of the polymer main chain
₃ H ₂ group, -SO ₃ H group, -COOH group, -OH group, -SH group, (Here, Z ₀ represents -Z ₁₀ group or -OZ ₁₀ group, and Z ₁₀ represents a hydrocarbon group), a graft copolymer formed by bonding a polar group selected from a formyl group and an amino group is also used. I can do it.

 Next, the present invention will be described in detail.

In general, a dispersant is a substance to be dispersed (here, a colorant, a colorant coated with a fixing resin, a fixing resin, and a dispersed substance is a dispersion, particularly a dispersed dispersion in the case of a liquid developer. It is known that it is important to have a component that has an affinity for a component and a solvent that adsorbs as an anchor and a solvate with respect to the solvent. Therefore, as the molecular structure of the dispersant, it is desirable to have a solvent-insoluble component and a solvent-soluble component in one polymer molecule.

A copolymer having components having different properties as described above can be easily obtained by copolymerizing two kinds of monomers.

However, if the two components are simply random copolymerized, the colorant alone such as pigment or dye can be dispersed in the fine particles, but the colorant or fixing resin itself coated with the fixing resin is dispersed in the fine particles. It is impossible.

In the case of a random copolymer, since a component adsorbed on toner particles and a component solvated exist randomly in one molecule, a dispersant is adsorbed across a plurality of toner particles, causing aggregation of the toner particles and causing a dispersing action. It is considered that the effect of stabilization on aggregation between particles is small because the dispersion is hindered or the adsorption layer of the dispersed polymer is thin.

On the other hand, in the case of a graft copolymer or a block copolymer, 1
Since the components adsorbed on the toner particles and the components solvated in the molecule are regularly arranged in the molecule, the thickness of the adsorption layer is large, stabilization based on steric effect and thermodynamic stability based on solvation It is thought that the dispersing action is brought about by this.

The dispersant of the present invention comprises at least one monofunctional macromonomer (M) and at least one monomer represented by the general formula (III).
A graft copolymer obtained by containing at least one kind of polymer and characterized by being substantially soluble in the non-aqueous solvent. Further, a graft copolymer obtained by bonding the above-mentioned specific polar group to one end of the polymer main chain of the graft copolymer can also be included. The method for obtaining a graft copolymer by the method of the present invention is called a macromonomer method.

The weight average molecular weight of the graft copolymer is 1 × 10 ^{4 to} 5
× 10 ⁵ , preferably 2 × 10 ⁴ to 2 × 10 ⁵ . When the weight-average molecular weight is less than 1 × 10 ⁴ or more than 5 × 10 ⁵ , the particle size of the dispersion becomes coarse or the distribution of the particle size becomes wide, and a preferable dispersion is not obtained. In general, when the molecular weight is low, an agglomerate is given instead of coarse particles or fine dispersion as a decrease in dispersing power. On the other hand, if the molecular weight is too high, the solubility of the dispersant in the non-aqueous solvent may decrease, and the dispersant may become substantially insoluble. When the molecular weight is in the above-mentioned range, these phenomena hardly occur, which is advantageous.

Here, the term "substantially soluble" means that when completely dissolved and dissolved when dissolved in a carrier liquid,
When translucent but homogeneously dissolved, it means any case where a swelling or cloudy state becomes a uniform solution or dispersion and shows a substantially uniform liquid state.

As a cause showing the cloudy state, the graft copolymer is
Micelles that are synthesized from two or more monomer components having different solubilities and form stems and branches and exhibit amphipathic properties , Aggregate with highly soluble parts oriented outward)
It is interpreted as being based on the formation of

The proportion of the monofunctional macromonomer (M) as a copolymer component of the graft copolymer is from 1% by weight to 90% by weight.
And preferably from 3% by weight to 70% by weight. If the proportion is less than 1% by weight, the number of grafted parts is significantly reduced, resulting in a chemical structure similar to that of a polymer composed of a one-component monomer. I will not be able to see it. On the other hand, when the proportion exceeds 90% by weight, the copolymerizability with the monomer represented by the general formula (III) becomes insufficient.

The proportion of the other copolymer component represented by the general formula (III) in the graft copolymer is 10%.
9999% by weight, preferably 30-97% by weight.

On the other hand, the macromonomer (M) of the present invention, which becomes the graft portion of the graft copolymer, has a weight average molecular weight of 1 ×.
It is 10 ³ -4 × 10 ⁴ , preferably 2 × 10 ^{3 -3} × 10 ⁴ . When the weight average molecular weight is less than 1 × 10 ³ , the redispersibility of the obtained dispersed resin particles is reduced. Also 4 × 10
^If it exceeds ⁴ , the copolymerizability with the monomer represented by the general formula (III) decreases, and a graft copolymer cannot be obtained.

Since the graft copolymer of the present invention as described above is substantially soluble in the non-aqueous solvent, it contains a repeating unit which becomes soluble in one or both of the polymer main chain and the graft. Therefore, in the macromonomer (M) component represented by the general formula (IIa) and the monomer component represented by the general formula (III), at least _one of Q ₀ and Q ₁ has 8 carbon atoms. Represents up to 22 aliphatic groups.

That is, as a repeating unit of the macromonomer (M) as a graft portion, Q ₀ in the general formula (IIa) has 8 carbon atoms.
In the case of representing less than an aliphatic group or an aromatic group and the case of a repeating unit represented by the general formula (IIb), the monomer represented by the general formula (III) constituting the polymer main chain has a Q ₁ represents an aliphatic group having 8 to 22 carbon atoms. When Q ₁ in the general formula (III) is an aliphatic group or an aromatic group having less than 8 carbon atoms, the repeating unit of the macromonomer (M) to be combined includes at least Q in the general formula (IIa) ₀
Represents a repeating unit of an aliphatic group having 8 to 22 carbon atoms.

Hereinafter, the content of the graft copolymer will be further described.

The monofunctional macromonomer (M) comprises a monomer represented by the general formula (III) only in one of the main chains of the polymer comprising the repeating unit represented by the general formula (IIa) or (IIb). Having a weight average molecular weight of 1 × 10 ³ to 4 × 10 ^{4 formed} by bonding a polymerizable double bond group represented by the general formula (I) which can be copolymerized with a polymer.
Is a macromonomer.

In the general formulas (I) and (IIa) and (IIb), a ₁ ,
The hydrocarbon groups contained in a ₂ , V, b ₁ , b ₂ , X ₀ , Q ₀ and Q each have the indicated carbon number (as an unsubstituted hydrocarbon group). It may be substituted.

In the formula (I), Z ₁ in the substituent represented by V is a hydrogen atom, and a preferred hydrocarbon group is a group having 1 to 1 carbon atoms.
22 optionally substituted alkyl groups (e.g., methyl, ethyl, propyl, butyl, heptyl, hexyl, octyl, decyl, dodecyl, tridecyl, tetradecyl, hexadecyl, octadecyl, 2-chloroethyl group, 2-bromoethyl group, 2-cyanoethyl group, 2-methoxycarbonylethyl group, 2-
A methoxyethyl group, a 2-bromopropyl group and the like), an optionally substituted alkenyl group having 4 to 18 carbon atoms (for example, a 2-methyl-1-propenyl group, a 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, etc.), having 7 to 7 carbon atoms.
12 aralkyl groups which may be substituted (for example, benzyl group, phenethyl group, 3-phenylpropyl group, naphthylmethyl group, 2-naphthylethyl group, chlorobenzyl group,
A bromobenzyl group, a methylbenzyl group, an ethylbenzyl group, a methoxybenzyl group, a dimethylbenzyl group, a dimethoxybenzyl group, etc.), an optionally substituted alicyclic group having 5 to 8 carbon atoms (for example, cyclohexyl group, Cyclohexylethyl group, 2-cyclopentylethyl group, etc.),
Or, an aromatic group which may be substituted having 6 to 12 carbon atoms (for example, a phenyl group, a naphthyl group, a tolyl group, a xylyl group,
Propylphenyl group, butylphenyl group, octylphenyl group, dodecylphenyl group, methoxyphenyl group, ethoxyphenyl group, butoxyphenyl group, decyloxyphenyl group, chlorophenyl group, dichlorophenyl group,
Bromophenyl group, cyanophenyl group, acetylphenyl group, methoxycarbonylphenyl group, ethoxycarbonylphenyl group, butoxycarbonylphenyl group, acetamidophenyl group, propioamidophenyl group, dodecyloylamidophenyl group, etc.) Groups consisting of 18 bridged hydrocarbons (eg, bicyclo [1,1,0] butane, bicyclo [3,2,1] octane, bicyclo [5,2,0] nonane, bicyclo [4,3,2] Undecane, adamantane, etc.).

V is In the case where is represented, the benzene ring may have a substituent.
Examples of the substituent include a halogen atom (eg, chlorine atom, bromine atom, etc.) and an alkyl group (eg, methyl group, ethyl group, propyl group, butyl group, chloromethyl group, methoxymethyl group, etc.).

a ₁ and a ₂ may be the same or different from each other, and are preferably a hydrogen atom, a halogen atom (for example, a chlorine atom,
Bromine atom), cyano group, alkyl group having 1 to 3 carbon atoms (eg, methyl group, ethyl group, propyl group, etc.), -CO
O-Z ₂ or -CH ₂ COOZ ₂ (Z ₂ is preferably a hydrogen atom or an alkyl group having 1 to 18 carbon atoms, an alkenyl group, an aralkyl group, an alicyclic group or an aryl group, which is substituted even if well, specifically, represent represent) the same contents as those described above Z _1.

In formula (IIa), X ₀ has the same meaning as V in formula (I), and b ₁ and b ₂ may be the same or different from each other;
It is synonymous with a ₁ or a ₂ in the above formula (I).

Q ₀ preferably represents an aliphatic group having 1 to 22 carbon atoms, and specifically, has the same content as the alkyl group described for Z ₁ described above.

The alkyl residue in the case where Y is an alkoxy group, specifically, those similar to the examples shown in the Q ₀ can be mentioned. Z ₃ represents an alkyl group, an aralkyl group or an aryl group, and specific examples thereof include the same examples as those described for Q ₀ .

Preferred ranges of X ₀ , b ₁ and b ₂ are each V,
The same contents as those described for a ₁ and a _2.

A ₁ and a ₂ of the formula (I) or b _{1 of the} formulas (II a) and (II b)
And more preferably one of b ₂ is a hydrogen atom.

The repeating unit of the macromonomer (M) of the present invention contains at least one unit represented by the general formula (IIa) or (IIb), and specific examples will be described below.
However, the scope of the present invention is not limited to this.

In the ^{_{following, Q a: -C p H 2p}} + 1 (p: 1~18 integer) or (Q: 1 to 4 integer) b: H or -CH ₃ l: 2 to 12 integer R ^a: represents a: (1-8 integer r) H or -C _r H _{2r + 1.}

The macromonomer (M) used in the present invention is, as described above, only at one end of a polymer main chain containing at least one kind of a repeating unit represented by the general formula (IIa) or (IIb). Having a chemical structure in which the polymerizable double bond group represented by the general formula (I) is directly bonded or bonded by an arbitrary linking group. Formula (I) component and formula (II
Examples of the group connecting the components a) and (II b) include a carbon-carbon bond (single bond or double bond) and a carbon-hetero atom bond (hetero atoms include, for example, an oxygen atom, a sulfur atom, a nitrogen atom, and a silicon atom. Atoms) and any combination of heteroatom-heteroatom bond atomic groups.

Preferred among the macromonomers (M) of the present invention are those represented by the formula (V).

Equation (V) In the formula, a ₁ , a ₂ , b ₁ , b ₂ , and V represent the same contents as those described in Formula (I), Formula (IIa), and (IIb), respectively.

T represents -Q represented by -X ₀ -Q ₀ or general formula represented by the general formula (II a) (II b) , respectively formula (II a),
Represents the same content as described in (IIb).

W ₁ is a simple bond or [Z ₄ and Z _{5 each} represent a hydrogen atom, a halogen atom (eg, a fluorine atom, a chlorine atom, a bromine atom, etc.), a lower alkyl group (eg, a methyl group, a propyl group, etc.), a cyano group, a hydroxyl group, etc.], CH = CH, -O-, -S-, -COO -, - SO ₂ -, -NHCOO-, -NHCONH-, [Z ₆ and Z ₇ represent a hydrogen atom, a hydrocarbon group or the like having the same content as Z ₁ above] or a single linking group selected from an atomic group such as Express.

In the general formulas (I), (IIa), (IIb) and (V), particularly preferred examples of each of X ₀ , Y, V, a ₁ , a ₂ , b ₁ and b ₂ are as follows. Shown in

The _{X 0 -COO -, - OCO -} , - O -, - CH 2 COO- or -CH ₂ OCO- is, Y is an alkyl or alkenyl group having 18 or less carbon atoms, as the V those of the (Wherein Z ₁ is a hydrogen atom), but a ₁ , a ₂ , b ₁ , and b ₂ include a hydrogen atom or a methyl group.

Hereinafter, in the general formula (V) Specific examples of the group represented by are shown below. However, the content of the present invention is not limited to these.

In the following, m ₁ represents an integer of _{1 to} 12, n ₁ represents an integer of 2 to 12, a: H or —CH ₃ .

(B) -20 CH ₂ = CH-OCO (CH _{2 m1} S- (B) -26 CH ₂ = CH-CH ₂ OCO (CH _{2 m1} S- The macromonomer (M) of the present invention can be produced by a conventionally known synthesis method. For example, a method by an ionic polymerization method in which various reagents are reacted with the terminal of a living polymer obtained by anionic polymerization or cationic polymerization to form a macromer, a reactive group such as a carboxyl group, a hydroxyl group, or an amino group in a molecule. Using the contained polymerization initiator and / or chain transfer agent, an oligomer having a terminal reactive group bond obtained by radical polymerization is reacted with various reagents to obtain a macromer by a radical polymerization method, polyaddition or polymerization. A method by a polyaddition condensation method in which a polymerizable double bond group is introduced into the oligomer obtained by the condensation reaction in the same manner as in the radical polymerization method, may be mentioned.

Specifically, P. Dreyfuss & RPQuirk, Encyclopedia Polymer Science Engineering (Encycl.Polym.Sci.Eng.), 7 , 551 (1987), PFRem
pp & E.Franta, Advanced Polymer Science (Adv.Polym.Sci.), 58 , 1 (1984), V.Percec, Applied Polymer Science (Appl.Polym.Sci.), 28
5 , 95 (1984), R. Asami, M. TakaRi, Macromolecular Chemie Supplement (Makromol. Chem. Suppl.), 1
2 , 163 (1985), P. Rempp, et al, supra (Makvomol. Chem. Sup.
pl.), 8 , 3 (1984), Yusuke Kawakami, Chemical Industry, 38 , 56 (19)
87), Yuya Yamashita, Polymer, 31 , 988 (1982), Shiro Kobayashi,
Polymer, 30 , 625 (1981), Toshinobu Higashimura, Journal of the Adhesion Society of Japan,
18 , 536 (1982), Koichi Ito, Polymer Processing, 35 , 262 (198
6), can be synthesized according to the methods described in the reviews of Kishiro Higashi, Takashi Tsuda, Functional Materials, 1987 , No. 10, 5, etc. and references and patents cited therein.

Next, together with the macromonomer (M) described above, a monomer represented by the general formula (III), which is a copolymer component of the graft copolymer, will be described.

In the formula (III), X ₁ has the same content as X ₀ in the formula (IIa), and preferably represents —COO—, —OCO—, —CH ₂ O
_{CO -, - CH 2 COO -} , - O-, or Is mentioned.

Q ₁ represents the same content and hydrogen atom as Q ₀ in formula (IIa), and preferably represents an aliphatic group having 1 to 22 carbon atoms,
Specifically, the same meaning as the aliphatic group Z ₁ of the formula (I).

d ₁ and d ₂ may be the same or different from each other, and specifically represent the same contents as a ₁ and a _{2 in} the formula (I). Preferably
One of d ₁ and d ₂ represents a hydrogen atom.

The graft copolymer may contain, in addition to the monomer represented by the general formula (III), which is a copolymer component, another monomer copolymerizable with the monomer. For example, acrylonitrile, methacrylonitrile, acrylamide,
Methacrylamide, styrene, chlorostyrene, bromostyrene, vinylnaphthalene, polymerizable double bond-containing heterocyclic compound (eg, vinylpyridine, vinylimidazoline, vinylthiophene, vinyldioxane, vinylpyrrolidone, etc.), unsaturated carboxylic acid ( For example, acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, etc.), itaconic anhydride, maleic anhydride and the like.

The monomer other than the general formula (III) may be any monomer as long as it is a copolymerizable monomer, and preferably, the proportion of these other monomers in all the polymerization components of the graft copolymer is , 30% by weight or less.

Further, the graft copolymer of the present invention may have the following specific polar group bonded only to one terminal of the polymer main chain.

That, -PO ₃ H ₂ group, -SO ₃ H group, -COOH group, -OH group, -S
H group, (Here, Z ₀ represents a —Z ₁₀ group or —OZ ₁₀ group, and Z ₁₀ represents a hydrocarbon group), a formyl group, and an amino group.

In polar groups, In the formula, Z ₀ represents a —Z ₁₀ group or —OZ ₁₀ group, and Z ₁₀ preferably represents a hydrocarbon group having 1 to 18 carbon atoms. Is more preferably a hydrocarbon group of Z _10, an optionally substituted aliphatic group (e.g., methyl group having 1 to 8 carbon atoms, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, butenyl group, pentenyl group Hexenyl group, 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 group, Tolyl, xylyl, mesityl, chlorophenyl, bromophenyl, methoxyphenyl, cyanophenyl, etc.).

Further, in a polar group of the present invention, an amino group, -NH _2, -NHZ ₁₁ or Represents Z ₁₁ and Z ₁₂ each independently represent a hydrocarbon group having 1 to 18 carbon atoms, preferably a hydrocarbon group having 1 to 8 carbon atoms, and specifically, the hydrocarbon group of Z ₁ described above. Represents the same content as.

Still more preferably, the hydrocarbon group of Z ₁₀ , Z ₁₁ and Z ₁₂ is an alkyl group having 1 to 4 carbon atoms which may be substituted, a benzyl group which may be substituted, or a phenyl group which may be substituted. No.

Here, the polar group has a chemical structure in which the polar group is directly bonded to one end of the polymer main chain or is bonded via an arbitrary linking group. Examples of the group connecting the graft copolymer component and the polar group include a carbon-carbon bond (single bond or double bond) and a carbon-hetero atom bond (hetero atoms include, for example, an oxygen atom, a sulfur atom, a nitrogen atom, and a silicon atom. Atoms), and any combination of heteroatom-heteroatom bond atomic groups.

Among the graft copolymers having a specific polar group bonded to one end of the polymer main chain of the present invention, preferred are those of the formula (VIa)
Or, as shown by the formula (VI b).

Wherein (V a) and _{(V b), a 1,} a 2, b 1, b 2, d 1, d 2,
X ₁ , Q ₁ , V, W ₁ , and T are represented by formulas (I) to (III) and (I
Indicates the same content as each symbol in V).

U represents the above-mentioned polar group bonded to one end of the graft copolymer.

W ₂ represents a mere bond or a group for linking the polar group U having the characteristic with the polymer main chain, and specifically has the same contents as described for W ₁ .

As described above, in the case of a graft copolymer having a specific polar group bonded to the terminal of the polymer main chain, a phosphono group, a carboxyl group, a sulfo group, a hydroxyl group, a formyl group are contained in the polymer main chain. , Amino group, mercapto group, Those which do not contain a copolymer component containing a polar group are preferred.

In order to produce a graft copolymer in which a specific polar group is bonded only to one terminal of these polymer main chains, various reagents are reacted with the terminal of a living polymer obtained by conventionally known anionic or cationic polymerization. Method (method by ionic polymerization method), method of radical polymerization using a polymerization initiator and / or a chain transfer agent containing a specific polar group in the molecule (method by radical polymerization method),
Alternatively, it can be easily produced by a synthesis method such as a method of converting a polymer having a terminal reactive group obtained by the ionic polymerization method or the radical polymerization method into a specific polar group of the present invention by a polymer reaction. Can be.

Specifically, P. Dreyfuss & RPQuirk, Encyclopedia Polymer Science Engineering (Encycl.Polym.Sci.Eng.), 7 , 551 (1987), Yoshiki Nakajo, Yuya Yamashita, "Dyes and Chemicals", 30 , 232 (1985), Akira Ueda, Susumu Nagai, "Science and Industry", 60 , 57 (1986), and the methods described in the references cited therein.

Examples of the polymerization initiator containing a specific polar group in the above-mentioned molecule include 4,4'-azobis (4-cyanovaleric acid), 4,4'-azobis (4-cyanovaleric chloride), 2,2 '-Azobis (2-cyanopropanol),
2,2'-azobis (2-cyanopentanol), 2,2'-
Azobis [2-methyl-N- (2-hydroxyethyl)
-Propioamide], 2,2'-azobis {2-methyl-
N- [1,1-bis (hydroxymethyl) ethyl] propioamide}, 2,2'-azobis {2-methyl-N- [1,1
-Bis (hydroxymethyl) -2-hydroxyethyl]
Propioamide｝, 2,2'-azobis [2- (5-methyl-2-imidazolin-2-yl) propane], 2,2 '
-Azobis [2- (4,5,6,7-tetrahydro-1H-1,3-
Diazepin-2-yl) propane], 2,2'-azobis [2- (3,4,5,6-tetrahydropyrimidin-2-yl) propane], 2,2'-azobis [2- (5-hydroxy -3,4,5,6-tetrapyrimidin-2-yl) propane], 2,2'-azobis {2- [1- (2-hydroxyethyl) -2-imidazolin-2-yl] propane},
2,2'-azobis [N- (2-hydroxyethyl) -2
-Methyl-propionamidine] and 2,2'-azobis [N- (4-aminophenyl) -2-methylpropionamidine].

As a chain transfer agent containing a specific polar group in the molecule, for example, a mercapto compound containing the polar group or a substituent derivable to the polar group (for example, thioglycolic acid, thiomalic acid, thiosalicylic acid, 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, 3-mercapto-1,2-propanediol, 1-mercapto- 2-propanol, 3-mercapto-2-butanol, mercaptophenol, 2-mercaptoethylamine, 2-mercaptoimidazole,
2-mercapto-3-pyridinol or the like, or an iodized alkyl compound containing the above polar group or substituent (eg, iodoacetic acid, iodopropionic acid, 2-iodoethanol, 2-iodoethanesulfonic acid, 3-iodopropanesulfone) Acid and the like). Preferably, a mercapto compound is used.

These chain transfer agents or polymerization initiators are each used in an amount of 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight, based on 100 parts by weight of the total monomers.

In the graft copolymer of the present invention having a polar group bonded to one end of the polymer main chain, the above-mentioned general formula (VI
a) or (VI b), where U
-W ₂ - further illustrates a specific example below moiety represented by. However, the scope of the present invention is not limited to these.

In the following, k ₁ represents an integer of 1 or 2, k ₂ represents an integer of _{2 to} 16, and k ₃ represents an integer of 1 or 3.

(C) -1 HOOCCH _{2 k1} S- (C) -3 HOOC (CH _{2 k2} OOC (CH _{2 k1} S− (C) -4 HOOC (CH _{2 k2} NHCO (CH _{2 k1} S− (C) -7 HO (CH _{2 k1} S- (C) -8 H ₂ N (CH _{2 k2} S- _{(C) -12 HO 3 S (} CH 2) 2 S- (C) -29 HOOC (CH ₂ ) ₂ NH (CH _{2 k1} S− (C) -30 HOOC (CH _{2 k2} CONH (CH _{2 k2} S−, etc.) As the macromonomer having a bonding group, various commercially available macromonomers can be used, and a polymerization product obtained by copolymerizing the macromonomer with the monomer represented by the general formula (III) can be used. Is very effective as the non-aqueous dispersant of the present invention.

Commercially available macromonomers are marketed by Satomer, Toa Gosei Chemical Industry Co., Ltd., Soken Chemical Co., Ltd., and Nippon Yushi Co., Ltd.

The following are commercially available macromonomers, which are sold by Toa Gosei Chemical Industry Co., Ltd.

Molecular weight; number average molecular weight by GPC method Here, a segment indicates a polymer portion of a macromonomer and corresponds to the general formulas (IIa) and (IIb). or,
The terminal groups correspond to the general formula (I).

In the present invention, the carrier liquid has an electric resistance of 1 × 10
A nonaqueous solvent having a resistivity of ⁹ Ω · cm or more and a dielectric constant of 3 or less can be used. Examples of the non-aqueous solvent include solvents such as linear or branched aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, and halogenated hydrocarbons. Octane, isooctane, decane, isodecane, dodecane, isododecane, nonane, isopar E, isoper G, isoper H, and isoper L, which are isoparaffinic petroleum solvents, in terms of their properties and odors
(Isopar “Isopar” is a trade name of Exxon), Isododecane (BP Chemical), Shell Sol 71 (manufactured by Shell)
IP Solvent 1620 (Idemitsu Petrochemical) is suitable.

As the pigments and dyes used in the present invention, various known inorganic pigments, organic pigments and dyes can be used.

For example, metal powder such as aluminum, magnetic iron oxide,
Metal oxides such as zinc oxide, titanium oxide and silicon dioxide; metal salts such as powdered cadmium lead selenchromate;
Hansa Yellow (CI11680), Benzidine Yellow G
(CI21090), benzidine orange (CI21110), fast red (CI37085), brilliant carmine 3
B (CI16015-Lake), phthalocyanine blue (CI74
160), phthalocyanine green (CI, 74260), Victoria blue (CI42595-Lake), spirit black (CI50415), oil blue (CI74350), alkali blue (CI42770A), first scarlet (CI
12315), Rhodamine 6B (CI45160), Fast Sky Blue (CI74200-Lake), Nigrosine (CI5041)
5), and carbon black. Surface-treated pigments,
For example, carbon black dyed with nigrosine, graft carbon obtained by graft polymerization of a polymer, and the like can be used.

As the charge control agent for the liquid developer used in the present invention, conventionally known charge control agents can be used. For example, metal salts of fatty acids such as naphthenic acid, octenoic acid, oleic acid and stearic acid, metal salts of sulfosuccinates, JP-B-45-556, JP-A-52-37435 and JP-A-52-37435
Oil-soluble sulfonic acid metal salts described in JP-B-37049, etc .; metal salts of phosphate esters described in JP-B-45-9954; abietic acid or hydrogenated abitin shown in JP-B-48-25666. Metal salts of acids, Ca salts of alkylbenzene sulfonic acids shown in JP-B-55-2620, JP-A-52-107837, JP-A-52-38937, JP-A-57-906
No. 43, metal salts of aromatic carboxylic acids or sulfonic acids described in JP-A-57-139753, nonionic surfactants such as polyoxyethylated alkylamines, fats and oils such as lecithin and linseed oil , Polyvinyl prolidone, organic acid esters of polyhydric alcohols, phosphate ester surfactants described in JP-A-57-210345, JP-B-56-210345
Sulfonic acid resins and the like shown in JP-A-24944 can be used. JP-A-60-21056, JP-A-61-50951
The amino acid derivatives described in the above item can also be used. The amino acid derivative is a compound represented by the following general formula (IV) or (V), or a reaction mixture obtained by further reacting a reaction mixture obtained by reacting an amino acid with a titanium compound in an organic solvent with water. .

(Wherein, R ₁ and R ₂ are a hydrogen atom, an alkyl group having 1 to 22 carbon atoms, a substituted alkyl group (dialkylamino group, alkyloxy group, alkylthio group as a substituent),
To 24 aryl groups, substituted aryl groups (substituents include dialkylamino, alkyloxy, alkylthio, chloro, bromo, cyano, nitro, and hydroxyl groups), aralkyl groups, and 1 to 22 carbon atoms , An arylsulfonyl group, an alkylphosphonyl group, an arylsulfonyl group and an arylphosphonyl group having 6 to 24 carbon atoms. R ₁ and R ₂ may be the same or different, and may form a ring with R ₁ -R ₂ , but are not hydrogen atoms at the same time. A represents an alkylene group having 1 to 10 carbon atoms or a substituted alkylene group. X represents a hydrogen atom, a monovalent to tetravalent metal, or a quaternary ammonium cation. n shows a positive integer. Furthermore, quaternized amine polymers described in JP-A-54-31739 and JP-B-56-24944 can be exemplified.

Among these, preferred are metal salts of naphthenic acid, metal salts of dioctylsulfosuccinic acid, lecithin,
The amino acid derivatives can be mentioned. More preferred examples include zirconium, cobalt, and manganese salts of naphthenic acid, calcium and sodium salts of dioctylsulfosuccinic acid, and metal salts of the compound of the general formula (IV). As the metal salt of the compound of the general formula (IV), a salt of titanium, cobalt, zirconium or nickel is particularly preferred.

As these charge control agents, two or more compounds can be used in combination.

In the present invention, various known resins which are insoluble or swellable in a carrier liquid can be used as a coating resin for imparting fixability to a colorant such as a pigment or a dye.

For example, butadiene rubber, styrene-butadiene rubber, loaminated rubber, rubbers such as natural rubber, styrene resin,
Synthetic resins such as vinyl toluene resin, acrylic resin, methacrylic resin, polyester resin, polycarbonates, polyvinyl acetate, rosin resin, hydrogenated rosin resin, and alkyd including modified alkyd such as linseed oil-modified alkyd Natural resins such as resins and polyterpenes are exemplified. Other phenolic resins including modified phenolic resins such as phenol formalin resins, natural resin modified maleic acid resin, pentaerythritol phthalate, chroman-indene resins, ester gum resins,
Vegetable oil polyamides and the like are also useful.

Of these, JP-A-58-121047, JP-A-58-127939, JP-A-58-127939
139155, JP-A-61-162058 and Japanese Patent Application No. 63-227831,
63-227832, 63-229161, 63-229162, 63-2291
No. 65 or other methacrylate-based copolymers or binary or ternary copolymers of methacrylate and styrene and its derivatives are prepared by eluting a photosensitive layer on an aluminum substrate with an alkaline etching solution. It is used as a resin for toner having good resist properties to an alkaline etching solution for printing plates.

As other good resins, JP-A-63-41272 and JP-A-63-4
The ethylene-based copolymer shown in No. 1273 can be mentioned. Generally, it is difficult for a resin for a toner having a good resist property to an alkali etching solution to be finely divided by wet dispersion. If a long-chain alkyl group having an affinity for the carrier liquid is introduced into the resin to improve the dispersibility, the resist properties decrease. Therefore, a styrene-based copolymer having a high styrene content and a strong resist property against alkali is often used as the resin.

The graft copolymer of the present invention, for these resins,
It has been found that fine particles can be dispersed and exhibit good dispersibility. In particular, even a resin alone can be wet-dispersed, and is suitable as a dispersant for a liquid developer for an electrophotographic printing plate.

The liquid developer of the present invention can be manufactured by a conventionally known method.

When a colorant such as a pigment or a dye is used alone as toner particles, it is wet-dispersed together with the dispersant of the present invention, and the concentrated liquid is diluted with a carrier liquid containing a charge control agent.

When the fixing resin is used alone without a colorant,
After the resin is pulverized once, it is similarly wet-dispersed.

Next, when the colorant is coated with a fixing resin, first, a colorant comprising a pigment or a dye, or both, and the fixing resin are mixed with a ball mill, a roll mill, a paint shaker, or the like in a lipophilic solvent of the resin. Is dispersed and kneaded using a disperser described above, and the solvent is removed by heating or the like to obtain a mixture.

Alternatively, the kneaded material is poured into a liquid in which the resin is not dissolved, and the mixture is obtained by reprecipitation.

Alternatively, the colorant and the resin are kneaded using a kneader such as a kneader, a three-roll mill or a Banbury mixer while being heated to a temperature equal to or higher than the melting point of the resin, and the mixture is cooled to obtain an admixture.

The thus obtained mixture is dry-pulverized or wet-dispersed as it is with a dispersant to obtain a toner concentrate. The solvent in the wet dispersion may be the carrier liquid itself, or may be a solution obtained by adding 1 to 20% by weight of a solvent having the above-mentioned resin such as toluene and acetone.

As a wet disperser, a ball mill, a paint shaker, a dyno mill and various sand grinders are used. In particular, a dispersing machine using fine glass beads as a dispersion media, such as a dyno mill, is suitable. The graft copolymer synthesized by the macromonomer method of the present invention is used by coexisting during the wet dispersion.

Here, it is important that the dispersant coexists during wet dispersion. When added after wet dispersion, it is effective for some degree of dispersion stabilization, but is not sufficient. During wet dispersion, the dispersant not only adsorbs on the toner particles, but also adsorbs on the pulverized toner particles between the rotating media or between the media and the wall of the disperser container, and agglomerates between the pulverized particles. In addition, the efficiency of wet dispersion is improved, and fine particles can be dispersed, so that the dispersing agent is adsorbed on the pulverized particles and coagulation is prevented. If the dispersant is not present, only pulverization occurs, and dispersion is not stabilized, causing aggregation between particles and dispersing into fine particles by repeating pulverization-aggregation as if it were pulverized again. It is impossible. In the case of adding a dispersant after wet dispersion, it is possible to maintain the particle size at the time of dispersion, but it is impossible to further reduce the particle size.

The dispersing agent may be added at the time of kneading since a dispersing effect is exhibited if it coexists at the time of dispersion.

However, during kneading, care must be taken so that the coating property of the fixing resin on the pigment or dye is not impaired. Therefore, it is preferable to add the dispersant during wet dispersion.

The amount of the dispersant to be added is 0.01 to 20 parts by weight, preferably 0.1 to 10 parts by weight, per 1 part by weight of the toner-forming particles. The amount of the dispersant to be added depends on the difficulty of dispersion of the toner-forming particles to be dispersed. In other words, a relatively small amount may be used when dispersion is relatively easy, such as in the case of a colorant alone, or when a colorant coated with a hardly dispersible coating agent is dispersed,
More dispersant is needed.

Although the toner particle concentration in the developer is not particularly limited, it is usually 0.01 g to 50 g, preferably 0.1 g to 20 g, based on the carrier liquid 1.
g. When a colorant is contained in the toner particles, the resin is used in an amount of 0.1 to 20 parts by weight, preferably 1 part by weight of the colorant.
0.5 to 10 parts by weight can be used.

The concentration of the dispersant is usually 0.01 g to 5
0 g, preferably 0.1 to 20 g. The charge control agent may be added by an addition method other than the above method. That is, they may be added at the time of kneading or wet dispersion, or may be used in combination. It is desirable to adjust the amount of the charge control agent to be contained in an amount of 0.001 g to 10 g per developer 1. More preferably, it is in the range of 0.01 g to 1 g.

As the photoconductor used in the present invention, a known organic photoconductor or inorganic photoconductor can be used. Also, a dielectric charged by a charging needle can be used.

Organic photoconductors include a wide range of well-known organic photoconductors. A specific example is “Research Disclosure”
(Research Disclosure) Magazine # 10938 (May 1973, p. 61 or later, a paper entitled "Electrophotographic Elements, Materials, and Processes").

Practical examples include, for example, poly-N-
Vinylcarbazole and 2,4,7-trinitrofluorene-
Electrophotographic photoreceptor comprising 9-one (US Pat. No. 3,484,23)
7), poly-N-vinylcarbazole sensitized with a pyrylium salt dye (Japanese Patent Publication No. 48-25658), an electrophotographic photoreceptor containing an organic pigment as a main component (JP-A-49-37543), a dye and a resin And an electrophotographic photosensitive member containing copper phthalocyanine dispersed in a resin (Japanese Patent Publication No. 52-1667). In addition, Journal of the Institute of Electrophotography, Vol. 25, No. 3 (1986)
On page 62 to page 76.

"Electoro photography" RMS as the inorganic photoconductor used in the present invention
Focal Press (London) by chaffert (1975) 26
Typical examples are various inorganic compounds disclosed on pages 0 to 374 and the like. Specific examples include zinc oxide, zinc sulfide, cadmium sulfide, selenium, tellurium alloy, selenium-arsenic alloy,
And selenium-tellurium-arsenic alloys.

(Examples) Production Examples and Examples of Example 1 for a dispersant of the present invention will be described below, but the present invention is not limited thereto.

Production example 1 of macromonomer 1: M-1 methyl methacrylate 100 g, mercaptopropionic acid
A mixed solution of 2 g and 200 g of toluene was heated to a temperature of 75 ° C. while stirring under a nitrogen stream. 1.0 g of 2,2'-azobisisobutyronitrile (abbreviation: AIBN) was added and reacted for 4 hours.
Further, 0.5 g of AIBN was added and reacted for 3 hours, and 0.3 g of AIBN was further added and reacted for 3 hours. Next, 8 g of glycidyl methacrylate, 1.0 g of N, N-dimethyldodecylamine and 0.5 g of t-butylhydroquinone were added to the reaction solution, and the mixture was stirred at a temperature of 100 ° C. for 12 hours. After cooling, the reaction solution was reprecipitated in methanol 2 to obtain 90 g of a white powder. The weight average molecular weight of the polymer was 11,000.

Macromonomer M-1: The molecular weight is a value in terms of polystyrene by the GPC method.

Macromonomer Preparation Examples 2 to 27: M-2 to M-27 The reaction was carried out in the same manner as in Preparation Example 1 except that in Example 1 of macromonomer, only the methacrylate was replaced with a compound corresponding to Table 1 below. Macro-monomers M-2 to M-
27 was synthesized. The weight average molecular weight of each obtained macromonomer was in the range of 10,000 to 15,000.

Production Example 28 of Macromonomer: M-28 A mixed solution of 100 g of dodecyl methacrylate, 5 g of thioethanol, and 200 g of toluene was stirred under a nitrogen stream while stirring.
Heated to a temperature of 70 ° C. 1.0 g of AIBN was added and reacted for 4 hours. Furthermore, 0.5g of AIBN is added, and for 3 hours,
0.3 g of AIBN was added and reacted for 3 hours. This reaction solution is
Cool to room temperature and add 2-carboxyethyl methacrylate 1
8.2 g was added, and a mixed solution of 24 g of dicyclohexylcarbodiimide (abbreviated as DCC) and 150 g of methylene chloride was added dropwise over 1 hour. 1.0 g of t-butylhydroquinone was added, and the mixture was stirred for 4 hours.

The filtrate obtained by filtering out the precipitated crystals was separated into methanol 2
Re-sinked inside. The precipitated oil was collected by decantation, dissolved in 150 ml of methylene chloride and reprecipitated in methanol 1. The oil was collected and dried under reduced pressure to obtain a polymer having a weight average molecular weight of 5,800 in a yield of 54 g.

Macromonomer M-28: Production Examples 29 to 35 of Macromonomer: M-29 to M-35 In the production examples of Macromonomer M-28, a methacrylate monomer (corresponding to dodecyl methacrylate) and an unsaturated carboxylic acid (corresponding to 2-carboxyethyl methacrylate) were used, respectively. Instead, similar to the production example of M-28,
Each of the macromonomers shown in Table 2 below was produced. The weight average molecular weight of each obtained macromonomer was 5,000 to 7,000.

Production Example 36 of Macromonomer: M-36 A mixed solution of 70 g of n-dodecyl methacrylate, 30 g of t-butyl methacrylate, 4 g of 2-mercaptoethylamine and 200 g of tetrahydrofuran was heated to 70 ° C. under a nitrogen stream. Add 1.0g of AIBN and react for 4 hours.
0.5 g of BN was added and reacted for 4 hours. Next, the reaction solution was cooled in a water bath to a temperature of 20 ° C., 6.5 g of triethylamine was added, and 5.6 g of acrylic acid chloride was added dropwise with stirring at a temperature of 25 ° C. or lower. After the addition, the mixture was further stirred for 1 hour. Thereafter, 0.5 g of t-butylhydroquinone was added, the mixture was heated to a temperature of 60 ° C., and stirred for 4 hours. After cooling, reprecipitation in methanol 2 was performed twice to obtain 63 g of a pale yellow viscous substance.
The weight average molecular weight was 6,600.

Macromonomer M-36: Production Example 37 of Macromonomer: M-37 A mixed solution of 100 g of octadecyl methacrylate, 150 g of tetrahydrofuran and 50 g of isopropyl alcohol was heated to a temperature of 75 ° C. under a nitrogen stream. 4.0 g of 4,4'-azobis (4-cyanovaleric acid) (abbreviation: ACV) was added and reacted for 5 hours, and 1.0 g of ACV was further added and reacted for 4 hours. After cooling, the reaction solution was reprecipitated in 1.5 of methanol, and the oil was collected by decantation and dried under reduced pressure. Yield 85
g.

50 g of the obtained oil (oligomer), 15 g of glycidyl methacrylate, 1.0 g of N, N-dimethyldodecylamine
And 1.0 g of 2,2'-methylenebis (6-t-butyl-p-cresol), and the mixture was stirred at a temperature of 100 ° C for 15 hours. After cooling, the reaction solution was reprecipitated in petroleum ether 1 to obtain 42 g of a white powder. The weight average molecular weight was 7,500.

Macromonomer M-37: Macromonomer Preparation Example 38: M-38 In Macromonomer Preparation Example 37, 50 g of the obtained intermediate oligomer, a mixed solution of 2-hydroxyethyl methacrylate 2.8 g and methylene chloride 100 g, were stirred at room temperature with DCC. 4.0 g, 4-dimethylaminopyridine 0.5 g
And a mixed solution of 10 g of methylene chloride was added dropwise over 1 hour.
The mixture was further stirred for 4 hours. The precipitated crystals are filtered off,
The operation of reprecipitating the filtrate in methanol 1 was performed twice,
The obtained powder was dried under reduced pressure. The yield was 43 g and the weight average molecular weight was 7,300.

Macromonomer M-38: Production Example of Resin for Dispersant-1: P-1 A mixed solution of 50 g of styrene, 50 g of macromonomer M-10 and 200 g of toluene was placed in a four-necked flask and heated to 80 ° C. while stirring under a nitrogen stream.

As a polymerization initiator, 1 g of 1,1′-azobis (1-cyclohexanecarbonitrile) was added, and the mixture was polymerized at 80 ° C. for 24 hours. After the polymerization, the mixture was cooled to room temperature, 200 g of toluene was further added, and the precipitate was reprecipitated in methanol 4. After filtration, the obtained white powder was dried, and powder 92 having a weight average molecular weight of 5.2 × 10 ⁴ was obtained.
g was obtained.

Dispersant P-1 Copolymerization ratio is above wt Production Examples 2 to 15 of Resin for Dispersant: P-2 to P-15 Production Examples except that styrene and macromonomer M-10 were replaced with the compounds shown in Table 3 below in Production Example 1 of P-1. By reacting in the same manner as in Example 1, each resin for a dispersant was produced. The weight average molecular weight of each resin was 3.0 × 10 ^{4 to} 6.0 × 10 ⁴ .

Production Example 16 of resin for dispersant: P-16 30 g of methyl methacrylate, 7% of macromonomer M-10
A mixed solution of 0 g, 0.8 g of thiomalic acid, 100 g of toluene and 50 g of isopropyl alcohol was heated to a temperature of 80 ° C. under a nitrogen stream. 1.0 g of 1,1'-azobis (1-cyclohexanecarbonitrile) (abbreviation: ABCC) was added and reacted for 24 hours. After cooling, the precipitate was reprecipitated in methanol 2, collected by filtration and dried to obtain 78 g of a white powder. Weight average molecular weight is 4.1 × 10 ⁴
Met.

Resin for resin P-16: Production Examples 17 to 25 of Resin for Dispersant: P-17 to P-25 In the production examples of P-16, methyl methacrylate, macromonomer M-10 and mercapto compound (thiomalic acid) are compounds corresponding to Table 4 below. And the same reaction as in Production Example 16 to produce each of the resins P-17 to P-25. The weight average molecular weight of each resin was 3.0 × 10 ^{4 to} 6 × 10 ⁴ .

Production Examples 26 to 31 of dispersant resin: P-26 to P-31 The same operation as in Production Example 1 except that in Example 1, azobis compounds shown in Table 5 below were used in place of the polymer initiator ABCC. Thus, each resin was manufactured.

The weight average molecular weight of each of the obtained resins is 3.0 × 10 ^{4 to} 6 × 10
^{Was 4} .

Production Example 32 of resin for dispersant: P-32 n-dodecyl methacrylate 85 g, macromonomer M
A mixed solution of -28 (15 g) and toluene (150 g) was heated to a temperature of 75 ° C under a nitrogen stream. Add 1.0g of AIBN for 4 hours,
Further, 0.5 g of AIBN was added and reacted for 3 hours. Or even AI
After adding 0.3 g of BN, the mixture was heated to a temperature of 90 ° C. and reacted for 2 hours. After cooling, the reaction product was reprecipitated in methanol 2 and the precipitated viscous substance was collected by decantation and dried under reduced pressure. The yield of the transparent viscous material is 76 g and the weight average molecular weight is 4.3
× 10 ⁴

Resin P-32 for dispersant: Production Examples 33 to 42 of Resin for Dispersant: P-33 to P-42 Except that in the production examples of P-32, n-dodecyl methacrylate and macromonomer M-28 were replaced with a mixture corresponding to Table 6 below. In the same manner as in Production Example 32, each resin P
-33 to P-42 were produced. The weight average molecular weight of each resin is 3.
It was 5 × 10 ^{4 to} 4.5 × 10 ⁴ .

Production Example 43 of Dispersant Resin: P-43 Octadecyl methacrylate 80 g, Macromonomer M
A mixed solution of 20 g of -1 and 150 g of toluene was heated to a temperature of 75 ° C. while stirring under a nitrogen stream. Add 1.0 g of ACV and react for 4 hours, then add 0.3 g of ACV and add 2 hours and AC
0.3 g of V. was added and reacted for 3 hours. After cooling, methanol 2
After reprecipitation, the resulting white powder was dried to obtain 76 g of a powder having a weight average molecular weight of 4.8 × 10 ⁴ .

Resin for resin P-43: Production Examples 44 to 57 of Resin for Dispersant: P-44 to P-57 Production Example 1 except that octadecyl methacrylate and macromonomer M-1 were replaced with the compounds shown in Table 3 below in Production Example 1 of P-1. By reacting in the same manner as in Example 1, each dispersion stabilizing resin was produced. Weight average molecular weight of each resin 3.5 × 10 ⁴ 〜
It was 5.0 × 10 ⁴ .

Production Example of Resin for Dispersant-58: P-58 A graft copolymer was synthesized using a styrene macromonomer sold as AS-6 by Toa Gosei Chemical Co., Ltd.

AS-6, 10 g, stearyl methacrylate (comonomer) 90 g, toluene 200 g are placed in a 500 ml four-necked flask equipped with a stirrer, thermometer, cooler and nitrogen gas inlet tube, and heated and stirred at 80 ° C. for 1 hour while sending nitrogen gas. After that, 1 g of 1,1'-azobis (1-cyclohexanecarbonitrile) was added as a polymerization initiator, and the mixture was polymerized at 80 ° C. for 24 hours. After the polymerization, the mixture was cooled to room temperature, 200 g of toluene was further added, and the precipitate was reprecipitated in methanol 4. The reprecipitate was further washed several times with methanol and dried in vacuo. Weight average molecular weight 6.0 × 1
0 ⁴ white powdery solid was obtained.

Production Example of Dispersion Resin -59 to 67: P-59 to P-67 In the same manner as in the production example of P-58, commercially available macromonomer AS-6 (styrene macromonomer) and AA-6 (methyl methacrylate macromer) ), A resin for a dispersant was synthesized.

Production Example 1 of Comparative Dispersant Resin: R-1 10 g of styrene, 90 g of stearyl methacrylate, and 200 g of toluene were placed in a four-necked flask in the same manner as in Production Example 1 of the dispersion resin, and nitrogen gas was passed through at 80 ° C. for 1 hour. After heating for 1 hour, 1 g of a polymerization initiator, 1,1'-azobis (1-cyclohexanecarbonitrile) was added, and the mixture was polymerized at 80 ° C for 24 hours. The polymer was reprecipitated in methanol in the same manner as in Production Example 1 to obtain a polymer. The polymer obtained here is a random copolymer.

Comparative Production Example-2,3: R-2-3 The molecular weight is 5.7 × 10 ⁴ -6.4 × 10 ⁴ in terms of weight average molecular weight. In addition, the molecular weight is a St-converted value by the GPC method.In Comparative Production Example-1, lauryl methacrylate and 2-ethylhexyl methacrylate were used in place of stearyl methacrylate, and Comparative Production Example 2 of a random copolymer was similarly used. 3 was synthesized.

Comparative Production Example 4, 5, 6: R-4 to 6 Comparative Production Example of Random Copolymer in Comparative Production Example 1, 2, 3 except that methyl methacrylate was used instead of styrene. 4,5,6 were synthesized.

Copolymerization ratio 10/90 weight ratio Comparative Production Example-4 Methyl methacrylate / ster R-4 Allyl methacrylate Comparative Production Example-5 Methyl methacrylate / lau R-5 Ryl methacrylate Comparative Production Example-6 Methyl methacrylate / 2-R-6 Ethylhexyl Methacrylate Comparative Production Example-7: R-7 A graft copolymer was synthesized by a method according to the method described in JP-B-60-18985 and JP-B-57-12985. This was synthesized by a method different from the macromonomer method graft copolymer as in the present invention.

Heat 300 g of toluene to 90 ° C. while passing nitrogen gas. A mixed solution of 180 g of lauryl methacrylate, 5 g of glycidyl methacrylate and g of benzoyl peroxide was added dropwise over 2 hours. After heating and stirring for 1 hour, 0.5 g of lauryl dimethylamine, 3 g of methacrylic acid and 0.1 g of hydroquinone were added. Allowed to react for hours. Toluene in this reaction
300 g was added, and a solution of 20 g of styrene and 1 g of azobisisobutylnitrile was added dropwise at 90 ° C. over 1 hour, followed by stirring for 1 hour.

After cooling to room temperature, the precipitate was reprecipitated in methanol 8, washed several times with methanol, and dried in vacuum. The molecular weight was 4.5 × 10 ⁴ in weight average. In this method, after copolymerizing a trunk monomer and glycidyl methacrylate as a graft active site, glycidyl methacrylate and acrylic acid are esterified, and a double bond is introduced into the trunk copolymer through an ester bond. . Next, a graft copolymer is obtained by copolymerizing with a monomer which becomes a branch.

Here, when the amount of glycidyl methacrylate was increased to increase the number of graft active sites, gelation occurred when the amount of glycidyl methacrylate was 15 g or more.

Example 1 Regarding the dispersibility of the pigment alone, the graft copolymer synthesized by the macromonomer method of the present invention (Production Example P-3,
Random copolymer (R-1,3) with the same monomer composition as in 8)
And a graft copolymer (Comparative Example-R-7) synthesized according to Japanese Patent Publication Nos. 57-12985 and 60-18985.
(Table-3).

Was dispersed for 2 hours with a paint shaker (manufactured by Toyo Seiki) using glass beads as a dispersion media.

After the dispersed liquid was diluted with Isopar H, the dispersion state was observed and the particle size was measured. The particle size is a value measured with a Naicizer (manufactured by Nikkaki).

Each of them showed a certain degree of dispersibility, but Comparative Examples R-1, R
-3 based on an undispersed material dispersed in the copolymer,
There was a lumpy lump. On the other hand, the comb-type graft copolymer of the present invention and the graft copolymer synthesized according to Japanese Patent Publication Nos. 57-12985 and 60-18985 showed uniform dispersibility.

The dispersion state was obtained by placing a diluent having a concentration of 1 g / solid dispersed solid in a glass container and visually observing the same.

Example 2 The dispersion was performed in exactly the same manner as in Example 1, except that the carbon black was changed to titanium oxide (wurtz type).

 Table 4 shows the dispersion results.

The graft copolymer of the present invention showed good dispersibility.
Similar results were obtained with zinc oxide powder, and the graft copolymer of the present invention showed good dispersibility.

Example 3 Here, the dispersibility of a colorant obtained by coating a pigment with a fixing resin was examined.

Kneading with a three-roll mill heated to 120 ° C (20 minutes)
did. After pulverizing with a pin mill, the mixture was wet-dispersed with the following composition.

It disperse | distributed using the paint shaker like Example-1. The dispersants used here are Synthesis Example P-3,8 and Comparative Synthesis Example R-1,3,7.

When Comparative Synthesis Examples R-1 and R-3 were used, the pulverized material became sticky and could not be dispersed at all.

On the other hand, in the case of using Synthesis Examples P-3 and 8 and Comparative Synthesis Example R-7, dispersion was possible without forming such a lump.

It diluted like dispersion | distribution and particle size were measured like Example-1. (-5) The dispersion dispersed with the dispersant of Comparative Example R-7 was prepared in Synthesis Example P
Compared with those dispersed with −3,8 dispersants, the particle size was large, the sediment of the diluent was large, and the dispersibility was poor.

Example-4 A pigment solid content of 1 g of the dispersion liquid dispersed in Example 3 (dispersion liquid dispersed with the dispersant of Synthesis Example P-3,8, Comparative Example R-7) was obtained.
/ Was diluted with Isopar G (manufactured by Exxon Chemical). At this time, as charge control agents, R ₁ = n-C ₈ H ₁₇ , R ₂ = n-C ₁₃ H ₂₇ CO, X = Ti, in general formula (IV) of the present specification.
A = C ₂ H ₄ and n = 2 were added so as to be 1 × 10 ⁻⁴ M per isopar G to prepare a liquid developer. The polarity was negative.

The liquid developer obtained here was used for Panacopy KV-3000.
When developed by Matsushita Electric Industrial Co., Ltd., a good image with high resolution and tone reproduction was obtained. Comparative Example R-7
In the case of the liquid developer obtained by dispersing in the above, toner having a large particle size adhered to the peripheral portion of the image, giving a rough image.

Further, when the stains of the developing portion of Panacopy KV-3000 were compared, the developer dispersed using the dispersant of the present invention showed that almost no stain was observed, but the dispersant of Comparative Example R-7 was used. With the dispersed developer, significant stains were generated (compared after taking 100 slides).

Next, when these liquid developers were aged at room temperature for 3 months, those dispersed with the graft copolymers of Synthesis Examples P-3 and P8 had a small amount of sedimentation and good redispersibility. However, those dispersed with the graft copolymer of Comparative Example R-7 had a large amount of sedimentation and poor redispersibility. When the same development was performed using the aged liquid developer, the former gave almost the same image as before the aging, whereas the latter not only increased the roughness of the image but also caused the image flow. did.

In Examples -1 and 3, the graft copolymers of the present invention both exhibited good dispersibility, but the random copolymers of Comparative Examples having the same monomer composition were dispersible in the case of pigment alone. However, the pigment coated with the fixing resin could not be dispersed at all. On the other hand, the graft copolymer of R-7 showed a certain degree of dispersibility for both the pigment alone and the coated pigment, but the dispersibility of the coated pigment was unsatisfactory. A good image could not be given.

Example-5 Dispersion was carried out in exactly the same manner except that the dispersant in Example-2 was changed to the copolymer of Synthesis Example P-61 and Comparative Example R-2. When the copolymer of Comparative Example R-2 was used as a dispersant, the whole formed one lump during dispersion and could not be dispersed at all.

On the other hand, those dispersed using the dispersant of Synthesis Example P-61 were uniformly dispersed.

Example-6 In Example-5, a dispersion liquid dispersed with the dispersant resin of Synthesis Example P-61 of the present invention was developed in the same manner as in Example-4 by adding the same charge control as in Example-4. An image having excellent fine line and gradation reproducibility was obtained.

Example-7 Here, the case where a fixing resin alone, in which a colorant such as a pigment or a dye was not present, was dispersed was examined.

(The fixing resin was previously pulverized by a pulverizer such as a pin mill.) The composition was dispersed in a paint shaker for 4 hours in the same manner as in Example-1.

The dispersant used here was Synthesis Example P-3, Comparative Example R-1,7
Is a copolymer of The results are shown in Table-7.

Although the graft copolymer of Synthesis Example P-3 of the present invention showed good dispersibility, the graft copolymer of Comparative Example R-7 could not be dispersed. In the Sendam copolymer of Comparative Example R-1, the fixing resin formed one lump and could not be dispersed at all.

Example-8 The dispersion liquid dispersed in Synthesis Example-2 of Example-7 was diluted with Isopar G so that the fixing resin content was 1 g /. As a charge control agent, zirconium naphthenate was added to a concentration of 1 × 10 ⁻⁵ M to prepare a positively chargeable liquid developer.

The printing plate precursor described below was charged positively with a corona charger, exposed to images, and subjected to reversal development according to a conventional method. The printing plate was heated at 140 ° C. for 2 minutes to fix the image.

40 parts of potassium silicate, potassium hydroxide
10 parts, benzyl alcohol 10 parts, ethanol 90 parts water 90
It was immersed in an etching solution diluted to 0 parts to remove non-image parts, and was sufficiently washed with water. The obtained printing plate sufficiently reproduced a dot image of 5% to 95% at 150 lines / inch.

The liquid developer of the present embodiment is obtained by dispersing only a fixing resin, and can be used in a field requiring only the resist property or the ink adhesion property such as a printing plate.

Preparation of printing master plate The surface of a JIS1050 aluminum sheet was grained with a rotating nylon brush using a Pumice-water suspension as an abrasive. At this time, the surface roughness (center line average roughness) was 0.5 μm. After washing with water, it was immersed in a 10% aqueous solution of caustic soda at 70 ° C. and etched so that the amount of aluminum dissolved was 6 g / m ² . After washing with water, it was neutralized by immersion in a 30% aqueous nitric acid solution for 1 minute, and washed thoroughly with water. Thereafter, electrolytic roughening was performed in a 0.7% nitric acid aqueous solution for 20 seconds using a short-wave alternating waveform having a voltage of 13 volts at the anode and a voltage of 6 volts at the cathode (described in Japanese Patent Publication No. 55-19,191). The surface was washed by immersion in a 50% solution of 50% sulfuric acid, and then washed with water. Further, the substrate was subjected to anodizing treatment in a 20% sulfuric acid aqueous solution so that the weight of the anodized film became 3.0 g / m ² , washed with water, and dried to prepare a substrate.

Next, the following coating solution for a photoconductive layer was applied to the above-mentioned substrate with a bar coater, and dried at 120 ° C. for 10 minutes to prepare a substrate.

(Coating solution for photoconductive layer) 1. 2.5 parts of hydrazone compound shown below 2. Copolymer of benzyl methacrylate and methacrylic acid (40% by mole of methacrylic acid) 75 parts 3. The following thiopyrylium salt compound 1.18 parts 4. Methylene chloride 510 parts 5. Methylcellosolve acetate 150 parts The printing plate thus prepared had a dry film thickness of 4 μm.

Examples 9 to 13 The dispersibility of carbon black coated with the fixing resin of Example 2 was examined for graft copolymers in which the copolymerization ratio of AS-6 (styrene macromonomer) and stearyl methacrylate was changed. Table 8 shows the results.

In each case, the uniformity of dispersion was good and excellent dispersibility was exhibited. In the case of Examples 11 and 12, a part of the dispersant behaves as insoluble particles in Isopar H or G, but a difference in dispersibility (dispersion ability) is found as compared with Examples -5 and 6. Did not.

Example -14 The same charge control agent as in Example 2 was added to these dispersions to prepare a negatively chargeable liquid developer.

When these liquid developers were developed using a photoreceptor described later, an image having excellent resolution, less roughness at edge portions, and good tone reproducibility was obtained.

These liquid developers had little sediment even when left at room temperature for three months or more, and the redispersibility of the sediment was good.

In addition, an image obtained after one year or more in a room gave almost the same image quality as the initial one.

Preparation of photoreceptor 10 g of polycarbonate (trade name “Lexan 121” manufactured by GE), 6 g of a diarylamine compound shown below,
60 mg of a styryl dye shown below as a sensitizer was dissolved in 80 ml of methylene chloride.

Next, this solution is coated on a 100-micron-thick polyethylene terephthalate film having a palladium vapor-deposited layer using an ear bar, and then dried to remove a coating solvent, to provide a 6-micron-thick photoconductive layer. A photographic light-sensitive material was prepared. The surface of the film was charged to +400 V and exposed to an image through a positive original to produce an electrostatic latent image.

Example -15 The liquid developer of Example -14 was loaded into the cassette file 7000R.
(Electronic file system manufactured by Fuji Photo Film Co., Ltd.), an image was developed, and an image having excellent resolution and good tone reproducibility was obtained.

Observation of the developed portion after continuous 10,000 frames of photographing with the same developer revealed that there was very little contamination with any of the developers.

[Effect of the Invention] The graft copolymer synthesized by the macromonomer method of the present invention has good dispersibility in any of a coloring agent such as a pigment or a dye, a coloring agent coated with a fixing resin and a fixing resin. showed that. Further, the liquid developer prepared using this dispersant had high resolution and excellent gradation reproducibility, and exhibited long-term storage stability and good redispersibility.

Claims (7)

(57) [Claims] (1) a monomer constituting a graft portion of the graft copolymer is at least one macromonomer having a polymerizable functional group at a terminal, and the graft copolymer has a volume resistivity of at least 10 ⁹ Ωcm; A non-aqueous dispersant which is substantially soluble in a non-aqueous solvent having a dielectric constant of 3 or less. 2. A non-aqueous dispersant for wet dispersion substantially soluble in a non-aqueous solvent having a volume resistivity of 10 ⁹ Ωcm or more and a dielectric constant of 3 or less, wherein the dispersant is represented by the following general formula (IIa) or (II): b)
And a weight average molecular weight of 1 × obtained by bonding a polymerizable double bond group represented by the following general formula (I) to only one end of a polymer main chain containing at least one of the polymer components represented by Patents comprising a graft copolymer comprising at least one of 10 ³ to 4 × 10 ⁴ monofunctional macromonomers (M) and at least one of monomers represented by the following general formula (III): The non-aqueous dispersant for wet dispersion according to claim 1. General formula (I) Wherein (I), V is _{-COO -, - OCO-, CH 2} l OCO-,
_{CH 2 l COO -, - O} -, - CONHCOO -, - CONHCO -, -
SO ₂ −, −CO−, Or Represents Here, Z ₁ represents a hydrogen atom or a hydrocarbon group, and l is 1
Represents an integer of ~ 3. a ₁ and a ₂ may be the same or different, and each represents a hydrogen atom, a halogen atom, a cyano group, a hydrocarbon group, -COO
-Z ₂ or -COO-Z ₂ via a hydrocarbon (Z ₂ represents a hydrogen atom or an optionally substituted hydrocarbon group). General formula (IIa) General formula (IIb) In formula (IIa), X ₀ has the same content as V in formula (I). Q ₀ represents a hydrogen atom, 6 aliphatic group or a carbon number of 1 to 22 carbon atoms
Represents 12 aromatic groups. Q is -CN or Represents Here, Y represents a hydrogen atom, a halogen atom, an alkoxy group or —COOZ ₃ (Z ₃ represents an alkyl group, an aralkyl group or an aryl group). b ₁ and b ₂ may be the same or different from each other, and represent the same contents as a ₁ and a ₂ in the formula (I). General formula (III) In formula (III), X ₁ has the same content as X ₀ in formula (IIa), and Q ₁ has the same content as Q ₀ in formula (II a). d ₁ and d ₂ may be the same or different from each other and represent the same contents as a ₁ and a ₂ in the formula (I). However, in the macromonomer (M) component represented by the general formula (II) and the monomer component represented by the general formula (III), Q
_At least _one of ₀ and Q ₁ has 8 to 2 carbon atoms.
Represents an aliphatic group of 2. 3. The method according to claim 1, wherein the dispersant is -PO at one end of the polymer main chain.
₃ H ₂ group, -SO ₃ H group, -COOH group, -OH group, -SH group, (Here, Z ₀ represents -Z ₁₀ group or -OZ ₁₀ group, and Z ₁₀ represents a hydrocarbon group.) It is a graft copolymer formed by bonding polar groups selected from formyl group and amino group. The non-aqueous dispersant for wet dispersion according to claim 2, characterized in that: 4. A non-aqueous solvent carrier liquid having a volume resistivity of 10 ⁹ Ωcm or more and a dielectric constant of 3 or less, comprising at least a pigment or a dye;
A liquid developer for electrophotography comprising a resin insoluble or swellable in the carrier liquid, one or more dyes or pigments coated with the resin, and a dispersant and a charge control agent, wherein the dispersant is described in claim 3. A liquid developer for electrostatography, which is the graft copolymer according to item 2. 5. A non-aqueous solvent carrier liquid having a volume resistivity of 10 ⁹ Ωcm or more and a dielectric constant of 3 or less, comprising at least a pigment or a dye;
A liquid developer for electrophotography comprising a resin insoluble or swellable in the carrier liquid, one or more dyes or pigments coated with the resin, and a dispersant and a charge control agent, wherein the dispersant is described in claim 4. A liquid developer for electrostatography, which is the graft copolymer according to claim 3. 6. A method for producing a printing plate by developing an electrostatic latent image formed on the surface of a printing original plate provided with an electrophotographic photosensitive layer on a conductive substrate with a liquid developer and then eluting a non-image portion. In, the liquid developer in a non-aqueous solvent carrier liquid having a volume resistivity of 10 ⁹ Ωcm or more and a dielectric constant of 3 or less, at least containing a resin insoluble or swellable in the carrier liquid, a dispersant and a charge control agent, 3. A liquid developer for a printing plate, wherein the dispersant is the graft copolymer according to claim 2. 7. A method for producing a printing plate by developing an electrostatic latent image formed on the surface of a printing original plate provided with an electrophotographic photosensitive layer on a conductive substrate with a liquid developer and then eluting a non-image portion. In, the liquid developer in a non-aqueous solvent carrier liquid having a volume resistivity of 10 ⁹ Ωcm or more and a dielectric constant of 3 or less, at least containing a resin insoluble or swellable in the carrier liquid, a dispersant and a charge control agent, A liquid developer for a printing plate, wherein the dispersant is the graft copolymer according to claim 3.