JP2684451B2 - Electrophotographic lithographic printing original plate - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to an electrophotographic lithographic printing original plate made by electrophotography, and more particularly, to a binder for forming a photoconductive layer of the lithographic printing original plate. It relates to improvement of resin.

(Prior art) At present, various types of offset masters for direct plate making have been proposed and put into practical use. Among them, a photoconductive particle such as zinc oxide and a binder resin are mainly used on a conductive support. In the photoreceptor provided with the photoconductive layer thus formed, a toner image having high lipophilicity is formed on the surface of the photoreceptor through a normal electrophotographic process, and then the surface is treated with a desensitizing solution called an etch solution. A technique for obtaining an offset original plate by selectively hydrophilizing a non-image portion is widely used.

In order to obtain good printed matter, first,
The original image is faithfully copied, the surface of the photoreceptor is easily compatible with the desensitizing solution, the non-image area is sufficiently hydrophilized, and at the same time, it has water resistance and, in printing, a photoconductive layer having an image. It is necessary to have such properties that the non-image area is not detached, has good compatibility with the dampening solution, and sufficiently retains the hydrophilicity of the non-image area so that no stain is generated even when the number of printed sheets is large.

It is already known that these properties are affected by the ratio of zinc oxide and binder resin in the photoconductive layer. For example, if the ratio of the binder resin to the zinc oxide particles in the photoconductive layer is reduced, the desensitizing property of the photoconductive layer surface is improved, and the background fouling is reduced, but on the other hand, the internal cohesive force of the photoconductive layer itself is reduced. And printing durability is reduced due to insufficient mechanical strength. Conversely, if the ratio of the binder resin is increased, the printing durability is improved,
Background dirt increases. Needless to say, the background stain is a phenomenon related to the quality of the desensitizing property of the surface of the photoconductive layer, but the desensitizing property of the surface of the photoconductive layer is bound to the zinc oxide in the photoconductive layer. It has become clear that not only depends on the resin ratio, but also greatly depends on the type of binder resin.

For example, silicone resins (Japanese Patent Publication No. 34-6670), styrene-butadiene resins (Japanese Patent Publication No. 35-1950), alkyd resins, maleic acid resins,
Polyamide (JP-B-35-11219), vinyl acetate resin (JP-B-41-2425), vinyl acetate copolymer (JP-B-41
No. 2426), an acrylic resin (Japanese Patent Publication No. 35-11216), and an acrylate copolymer (for example, Japanese Patent Publication No. 35-11219).
Nos. JP-B-36-8510, JP-B-41-13946, etc.) are known. However, in electrophotographic photosensitive materials using these resins, 1) the chargeability of the photoconductive layer is low, and 2)
Poor quality (especially halftone dot reproducibility / resolution) of the copied image, 3) low exposure sensitivity, 4) no desensitization even if desensitized for use as an offset master. 5) The surface of the printed matter is smeared when the offset printing is performed. 5) The film strength of the photosensitive layer is not enough, and the offset printing causes the photosensitive layer to be detached. (For example, high temperature and high humidity)
However, there is a problem that the image quality is easily affected.

In particular, as the offset original plate, as described above, there are many problems that scumming occurs due to insufficient desensitizing property, and in order to improve this, development of zinc oxide binder resin to improve desensitizing property is variously studied. Has been done. For example,
No. 31011 discloses a resin having a weight average molecular weight of 1.8 to 10 × 10 ⁴ and a glass transition point of 10 to 80 ° C., which is obtained by copolymerizing a (meth) acrylate monomer with another monomer in the presence of fumaric acid. A combination of a monomer and a copolymer comprising a monomer other than fumaric acid;
No. 54027 uses a terpolymer containing a (meth) acrylate having a substituent having a carboxylic acid group at least 7 atoms away from the ester bond. No. 57-202544 discloses a method involving acrylic acid and hydroxyethyl (meth) acrylate.
Using a terpolymer or a terpolymer, in JP-A-58-68046, a terpolymer containing a (meth) acrylic acid ester having a C6-12 alkyl group as a substituent and a carboxylic acid-containing vinyl monomer It is described that those containing a copolymer are effective in improving the desensitizing property of the photoconductive layer. However, even those resins that are said to be effective in improving the desensitizing property were not sufficient in terms of background stain and printing durability when actually evaluated.

Further, as a binder resin, a resin using a resin containing a functional group that generates a hydrophilic group by decomposition has been studied. For example, a resin containing a functional group that generates a hydroxyl group by decomposition (Japanese Patent Laid-Open No. 195684, JP-A-62-2104
No. 75, JP-A No. 62-258476) and those containing a functional group which generates a carboxyl group by decomposition (JP-A No. 62-212669)
No.) Alternatively, it contains a functional group that generates a hydroxyl group or a carboxyl group by decomposition, and also prevents water solubility and water swelling by bridging between polymers to further prevent background fouling and improve printing durability. (Japanese Patent Application Laid-Open Nos. 1-191157, 1-197765, 1-1918)
No. 60, JP-A-1-185667, JP-A-1-179052, JP-A-1-191158 and the like.

(Problems to be Solved by the Invention) However, when these are actually evaluated in detail as a lithographic printing plate precursor, they are in an amount sufficient to sufficiently enhance the hydrophilicity of the non-image area and to improve the prevention of background fouling. When these resins are used, electrophotographic characteristics (especially charge retention in the dark, light sensitivity, etc.) fluctuate during environmental changes (high temperature / high humidity or low temperature / low humidity),
In some cases, stable and good copied images could not be obtained. As a result, when this was used as a printing original plate, the printed image of the printed matter was deteriorated or the effect of preventing background contamination was reduced.

In addition, in the electrophotographic lithographic printing plate precursor as a digital direct lithographic printing plate precursor, when a scanning exposure method using a semiconductor laser beam is adopted, the exposure time becomes longer than that in the entire surface simultaneous exposure method using visible light, and Since the exposure intensity is also limited, higher performance is required for electrostatic characteristics, particularly dark charge retention characteristics and photosensitivity.

On the other hand, in the above-mentioned known original plate, the electrophotographic characteristics are deteriorated, and the actual copied image is liable to cause ground fog,
In addition, fine lines are skipped and characters are blurred. As a result, when printed as a lithographic printing original plate, the image quality of the printed matter is reduced, and the effect of preventing background contamination by improving the hydrophilicity of the non-image portion of the binder resin is lost. I have.

In view of the above situation, the present invention provides an electrophotographic lithographic printing plate precursor having electrostatic characteristics (particularly dark charge retention and light sensitivity).
Lithographic printing master plate that reproduces a copy image that is faithful to the original image and that does not generate dot smears as well as uniform background smear on the printed material and that has excellent printing durability To provide.

Another object of the present invention is to provide an electrophotographic lithographic printing plate which is effective for a scanning exposure method using a semiconductor laser beam.

(Means for Solving the Problems) An object of the present invention is to provide an electrophotographic photosensitive member comprising a conductive support and a photoconductive layer comprising at least one layer of photoconductive zinc oxide and a binder resin. Wherein the binder resin contains at least one of a fluorine atom and a silicon atom, and has at least one of a sulfo group, a phosphono group, a carboxyl group, and a hydroxyl group by decomposition. And a monofunctional monomer having a functional group capable of forming a compound represented by the following general formula (IIa) or (II
b) at least one of the polymer components
COOH group, -PO ₃ H ₂ group, -SO ₃ H group, -OH group, At least one component containing at least one polar group selected from a group wherein R represents a hydrocarbon group or an -OR 'group (R' represents a hydrocarbon group), a -CHO group and a cyclic acid anhydride-containing group. Weight average molecular weight 2 in which a polymerizable double bond group represented by the following general formula (I) is bonded to only one end of a polymer main chain containing at least one kind of contained polymer component
It has been found that the problem can be solved by an electrophotographic lithographic printing plate precursor containing at least one graft type copolymer comprising at least 10 ⁴ or less monofunctional macromonomers.

General formula (I) Wherein (I), X ₀ is -COO -, - OCO -, - CH 2 OCO -, -
_{CH 2 COO -, - O -} , - SO 2 -, - CO -, - CONHCOO -, -
CONHCONH-, Or Wherein Z ₁ represents a hydrogen atom or a hydrocarbon group.

a ₁ and a ₂ may be the same or different from each other, and each represents a hydrogen atom, a halogen atom, a cyano group, a hydrocarbon group, -COO-Z
₂ represents —COO—Z ₂ (Z ₂ represents a hydrocarbon group) through a hydrocarbon.

General formula (IIa) General formula (IIb) Wherein (II a) or (II b), X ₁ represents the same content as X ₀ in formula (I). Q ₁ represents an aliphatic group having 1 to 18 carbon atoms or an aromatic group having 6 to 12 carbon atoms. b ₁ and b ₂ may be the same as or different from each other, and have the same contents as a ₁ and a ₂ in the formula (I).

Q ₀ is -CN, -CONH ₂ or And 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).

The present invention contains at least one hydrophilic group (sulfo group, phosphono group, carboxyl group by decomposition) containing at least a fluorine atom and / or a silicon atom as at least one binder resin for a photoconductive layer of a lithographic printing plate precursor. Group and / or hydroxyl group) -containing monofunctional monomer containing at least one functional group and a monofunctional macromonomer containing a specific polar group as a monomer component. It is characterized by containing coalescence. Thereby, the lithographic printing plate precursor according to the present invention,
Reproduces a copy image that is faithful to the original image, and because the non-image area has good hydrophilicity, it does not cause scumming, the photoconductive layer has good smoothness and electrostatic characteristics, and printing durability is good. It has the advantage of being excellent.

Furthermore, the lithographic printing plate precursor of the present invention is characterized by being unaffected by the environment during the plate making process and having excellent storage stability before the process.

For a lithographic printing plate, it is important that the surface portion of the non-image portion is sufficiently hydrophilic. On the other hand, a known resin of a type that generates a hydrophilic group by the decomposition reaction is a photoconductive resin. It is uniformly dispersed throughout the layer. Accordingly, in order to sufficiently hydrophilize the surface of the known resin, a hydrophilic group-forming functional group is present in the entire photoconductive layer and in a large proportion thereof. It is considered that the appropriate interaction between the resin and the binder resin is not maintained sufficiently, and environmental fluctuations and a decrease in electrophotographic characteristics in the case of the scanning exposure method are caused.

On the other hand, the binder resin according to the present invention is a polymer component containing a functional group that protects a hydrophilic group with a protective group containing a fluorine atom and / or a silicon atom and decomposes to generate a hydrophilic group. : A graft type copolymer comprising a segment A part and a polymer component corresponding to a monofunctional macromonomer containing a specific polar group as a monomer component: a segment B part. The resin of the present invention has a specific behavior in the photoconductive layer, unlike the conventionally known random copolymer. That is, when the resin of the present invention is used as the binder resin, the segment B portion and the photoconductive zinc oxide appropriately interact with each other, and good electrophotographic characteristics can be maintained, and the segment A portion and the segment B portion are It is presumed that a microphase-separated structure is formed due to the difference in compatibility, and moreover, there is a tendency that there are many segment A portions that later generate hydrophilic groups in the surface layer portion. It is considered that the effect of improving the above is further enhanced, and it appears as an effect of preventing the background stain during printing.

Furthermore, in the resin of the present invention in which a hydrophilic group is generated by the desensitization treatment, the hydrophilic segment A portion faces the surface side, while the lipophilic segment B portion faces the opposite side of the surface, and the like. Interacts with the binder resin and / or zinc oxide to exhibit an anchor effect, thereby suppressing elution of the resin into the etchant and / or the fountain solution during printing. And good hydrophilicity can be maintained, and a large number of prints with good image quality can be obtained.

Hereinafter, a fluorine atom and / or silicon atom-containing functional group which is decomposed to form at least one hydrophilic group (hereinafter, may be simply referred to as a hydrophilic group-forming functional group) used in the present invention. explain in detail.

Although the hydrophilic group-forming functional group of the present invention generates a hydrophilic group by decomposition, the number of hydrophilic groups generated from one functional group may be one or two or more.

According to one preferred embodiment of the present invention, the hydrophilic group-forming functional group-containing graft copolymer has the general formula (III) to (V
It is a resin containing at least one functional group represented by I).

-COOH group as one of the preferred embodiments of the hydrophilic group-forming functional group of the present invention, the functional group which forms a -SO ₃ H group or a -PO ₃ H ₂ group will be described.

Formula (III) -V-O-L 1 V is Represents

L ₁ is -CF ₃ , Or represents the _{CH 2) 2 SO 2 P 8} .

L ₁ In the case of, P ₁ is a hydrogen atom, -CN group, -CF ₃ group,
Represents a —COR ₁₁ group or a —COOR ₁₁ group. However, R ₁₁ has 1 carbon atom
To 6 alkyl groups (for example, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, etc.) and an optionally substituted aralkyl group having 7 to 12 carbon atoms (specifically, a benzyl group, a phenethyl group) , A chlorobenzyl group, a methoxybenzyl group, a chlorophenethyl group, a methylphenethyl group, etc.), an aromatic group (for example, a phenyl group or a naphthyl group which may contain a substituent: specifically, a phenyl group, a chlorophenyl group, a dichlorophenyl) Group, methylphenyl group,
Methoxyphenyl group, acetylphenyl group, acetamidophenyl group, methoxycarbonylphenyl group, a naphthyl group, _{etc.), CH 2 n1 CF 2 m1} CF 2 H ( wherein n ₁ is an integer and m ₁ 1 or 2 for 1-8 Represents an integer), CH _{2 n2} C
_m2 H _{2m2 + 1} (where n ₂ is an integer of 0, 1 or 2 and m ₂ is 1 to
Represents an integer of 8) or [N ₃ represents an integer of 1 to 6 and m ₃ represents an integer of 1 to 4,
Represents a single bond or -O-.

R ₁₂ and R ₁₃ may be the same or different, and each is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms (specifically, a methyl group,
Ethyl group, propyl group, butyl group, etc.).

R ₁₄ , R ₁₅ and R ₁₆ may be the same or different and each represents a hydrocarbon group which may be substituted and has 1 to 12 carbon atoms or an —OR ₁₇ group (R ₁₇ represents a hydrocarbon group). Here, the specific contents of the hydrocarbon group and the hydrocarbon group of R ₁₇ represent the same contents as those of the aforementioned hydrocarbon group of R ₁₁ ].

P ₂ represents a —CF ₃ group, a —COR ₁₁ group, or a —COOR ₁₁ group (provided that R ₁₁ represents the same symbol as described above).

Furthermore, it is necessary to at least substituent fluorine atom or a silicon atom contained in either one is selected at P ₁ and P _2.

L ₁ In the formula, P ₃ , P ₄ and P ₅ represent the same contents as R ₁₄ , R ₁₅ and R ₁₆ .

L ₁ For, P ₆ and P ₇ may be the same or different, and each R ₁₁
Represents the same content as. However, either the P ₆ and P ₇ is at least a fluorine atom or a silicon atom-containing substituents are chosen.

L ₁ is - _{(CH 2) 2 SO 2 P} 8, P 8 is CH _{2 n1} CF _2
m1 CF ₂ H group, CH ₂ ) _n2 C _m2 H _{2 m2 + 1} group or The expressed, the contents represent the same contents as the contents respectively corresponding in R ₁₁ described above.

L ₁ In the case of, V ₁ represents an organic residue forming a cyclic imide group, which contains a substituent containing a fluorine atom and 1 or a silicon atom. Specifically, examples of the cyclic imide ring residue to be formed include a maleimide group, a glutaconimide group, a succinimide group, and a phthalimide group. or,
As the substituent containing a fluorine atom and / or a silicon atom, a hydrocarbon group represented by P _8, and -S-P ₉ group (P ₉
Represents the same content as P _8), and the like.

As one of the preferred embodiments of the present invention, a hydroxyl group-forming functional group can be mentioned, and specifically, the following general formula (IV)
(VI).

In the general formula (IV) -O-L ₂ formula (IV), L ₂ is Represents P ₃ , P ₄ and P ₅ are the same as those described above.

General formula (V) In formula (V), R ₃ and R _{4, which} may be the same or different, each represents a hydrogen atom or a group having the same content as R ₁₁ . However, at least one of R ₃ and R ₄ is selected from a substituent containing a fluorine atom and / or a silicon atom.

V ₂ represents a carbon-carbon bond which may be via a hetero atom (provided that the number of atoms between oxygen atoms is within 5).

General formula (VI) In the formula (VI), V ₂ , R ₃ and R ₄ are as defined above.

Specific examples of the functional groups represented by formulas (III) to (VI) of the present invention are described below. However, the scope of the present invention is:
It is not limited to these.

(14) -SO ₂ -O-CF ₃ (15) -SO ₂ -OCH ₂ ) ₂ SO ₂ CF ₃ (16) -SO ₂ -OCH ₂ ) ₂ SO ₂ CH ₂ CF ₃ (17) -SO _2- OCH ₂ ) ₂ SO ₂ (CH ₂ ) ₂ C ₃ F ₇ (24) -O-Si (C 2 H 5) 3 As described above, the copolymer component containing the functional groups of the general formulas (III) to (VI) used in the method for producing a desired resin by the polymerization reaction will be described more specifically.
For example, a component represented by the following general formula (VII) can be mentioned. However, it is not limited to these copolymer components.

General formula (VII) In formula (VII), X ′ represents —O—, —CO—, —COO—, —
OCO-, _{-CH 2 COO -, - CH 2} OCO-, Represents an aromatic group or a heterocyclic group (provided that e ₁ , e ₂ , e ₃ ,
e ₄ each represents a hydrogen atom, a hydrocarbon group, or Y′-W] in formula (VII), and f ₁ and f ₂ may be the same or different, and a hydrogen atom, a hydrocarbon group, or a formula Y'-W] in (VII), and l represents an integer of 0 to 18].

Y ′ represents a carbon-carbon bond which connects the bonding group X ′ and the bonding group [W] and may be via a hetero atom (hetero atoms represent an oxygen atom, a sulfur atom and a nitrogen atom); For example -(CH = CH, -O-, -S-, -COO -, - CONH -, - SO 2 -, - SO 2 NH -, - NHCOO-,
Which has the constitution alone or in combination of coupling units such as -NHCONH- (where f _3, f _4, f ₅ are each the same meaning as the f _1, f _2).

W represents a functional group represented by formulas (III) to (VI).

c ₁ and c ₂ may be the same or different, and a hydrogen atom, a halogen atom (for example, a chlorine atom, a bromine atom, etc.), a cyano group, a hydrocarbon group (for example, a methyl group, an ethyl group, a propyl group, a butyl group, Alkyl groups having 1 to 12 carbon atoms which may be substituted such as methoxycarbonylmethyl group, ethoxycarbonylmethyl group and butoxycarbonylmethyl group, aralkyl groups such as benzyl group and phenethyl group, phenyl group, tolyl group, xylyl group, chlorophenyl Groups such as aryl groups), or —COOZ ₀ (Z ₀ is an alkyl group, alkenyl group, aralkyl having 1 to 18 carbon atoms, which may be substituted with a substituent including the —W group in formula (VII). Group, alicyclic group, and aromatic group).

In addition, there is no [-X'-Y'-] bond residue in the formula (VII), You may connect a part and -W directly.

Next, the monofunctional macromonomer (M) constituting another copolymer component of the graft copolymer of the present invention will be described.

The monofunctional macromonomer (M) is prepared by adding a polymerizable double bond group represented by the general formula (I) to the general formulas (IIa) and (II)
at least one with a specific polar group (-COOH group of the polymer component represented by b), -PO ₃ H ₂ group, -SO ₃ H group, -OH
Group, A CHO group and / or an acid anhydride-containing group) and a weight-average molecular weight of 2 × 10 ⁴ , which is bound to only one end of a polymer main chain containing at least one of the polymer components.
These are:

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

In the general formula (I), X ₀ represents -COO-, -OCO-,-
_{CH 2 OCO -, - CH 2} COO -, - O -, - SO 2 -, - CO -, - C
ONHCOO−, −CONHCONH−, Or Represents Here, Z ₁ is, in addition to a hydrogen atom, a preferable hydrocarbon group as an optionally substituted alkyl group having 1 to 18 carbon atoms (for example, methyl group, ethyl group, propyl group, butyl group, heptyl group, hexyl group). Group, octyl group, decyl group, dodecyl group, hexadecyl group, octadecyl group, 2
-Chloroethyl group, 2-bromoethyl group, 2-cyanoethyl group, 2-methoxycarbonylethyl group, 2-methoxyethyl group, 3-bromopropyl group, etc.), having 4 to 18 carbon atoms.
An optionally substituted alkenyl group (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, etc.), aralkyl group having 7 to 12 carbon atoms which may be substituted (for example, benzyl group, phenethyl group, 3-phenylpropyl group, naphthylmethyl group, 2-
A naphthylethyl group, a 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, a cyclohexyl group, a 2-cyclohexylethyl group,
2-cyclopentylethyl group or the like and an optionally substituted aromatic group having 6 to 12 carbon atoms (for example, phenyl group, naphthyl group, tolyl group, xylyl group, propylphenyl group, butylphenyl group, octylphenyl group, dodecyl) Phenyl, methoxyphenyl, ethoxyphenyl, butoxyphenyl, decyloxyphenyl, chlorophenyl, dichlorophenyl, bromophenyl, cyanophenyl, acetylphenyl, methoxycarbonylphenyl, ethoxycarbonylphenyl, butoxycarbonyl Phenyl group, acetamidophenyl group, propioamidophenyl group, dodecyloylamidophenyl group, etc.).

X ₀ 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.), an alkyl group (eg, methyl group, ethyl group, propyl group, butyl group, chloromethyl group, methoxymethyl group, etc.), an alkoxy group (eg, methoxy group, Ethoxy groups,
And a propoxy group and a butoxy group).

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, etc.), cyano group, alkyl group having 1 to 4 carbon atoms (eg, methyl group, ethyl group, propyl group, butyl group, etc.), —COO—Z ₂ or COOZ ₂ (Z ₂ is , Preferably an alkyl group having 1 to 18 carbon atoms, an alkenyl group, an aralkyl group, an alicyclic group or an aryl group, which may be substituted, and specifically, those described for Z ₁ above. Represents the same content).

Examples of the hydrocarbon in the —COO—Z ₂ group via the above hydrocarbon include a methylene group, an ethylene group, and a propylene group.

More preferably, for general formula (I), X ₀ is -COO
-, - OCO -, - CH 2 OCO -, - CH 2 COO -, - O -, - CON
HCOO -, - CONHCONH -, - CONH -, - SO 2 NH- or And a ₁ and a ₂ may be the same or different from each other, and each is a hydrogen atom, a methyl group, —COOZ ₄ or —CH ₂ COOZ ₄ {Z
₄ more preferably represents an alkyl group having 1 to 6 carbon atoms (eg, methyl group, ethyl group, propyl group, butyl group, hexyl group, etc.). Represents｝. Even more preferably,
One of a ₁ and a ₂ represents a hydrogen atom.

That is, as the polymerizable double bond group represented by the general formula (I), specifically, And the like.

In the general formula (IIa) or (IIb), X ₁ is a group represented by the formula (I)
Represents the same content as X _{0 in} . b ₁ and b ₂ may be the same or different, and represent the same contents as a ₁ and a ₂ in the formula (I).

Q ₁ represents an aliphatic group having 1 to 18 carbon atoms or an aromatic group having 6 to 12 carbon atoms.

Specifically, an alkyl group having 1 to 18 carbon atoms which may be substituted (for example, a methyl group, an ethyl group, a propyl group, a butyl group, a heptyl group, a hexyl group, an octyl group, a decyl group,
Dodecyl, tridecyl, hexadecyl, octadecyl, 2-chloroethyl, 2-bromoethyl, 2
-Hydroxylethyl group, 2-methoxyethyl group, 2-
Ethoxyethyl group, 2-cyanoethyl group, 3-chloropropyl group, 2- (trimethoxysilyl) ethyl group, 2-
Tetrahydrofuryl group, 2-thienylethyl group, 2-N,
N-dimethylaminoethyl group, 2-N, N-diethylaminoethyl group, etc., C5-C8 cycloalkyl group (for example, cycloheptyl group, cyclohexyl group, cyclooctyl group, etc.), C7-C12 substitution Aralkyl groups (eg, benzyl group, phenethyl group, 3-phenylpropyl group, naphthylmethyl group, 2-naphthylethyl group, chlorobenzyl group, bromobenzyl group, dichlorobenzyl group, methylbenzyl group, chloro-methyl An aliphatic group such as a benzyl group, a dimethylbenzyl group, a trimethylbenzyl group, a methoxybenzyl group, and the like;
Optionally substituted aryl group (for example, phenyl group,
And aromatic groups such as a tolyl group, a xylyl group, a chlorophenyl group, a bromophenyl group, a dichlorophenyl group, a chloro-methyl-phenyl group, a methoxyphenyl group, a methoxycarbonylphenyl group, a naphthyl group and a chloronaphthyl group.

In formula (IIa), preferably X ₁ -COO-, -OCO
_{-, - CH 2 COO -,} - CH 2 OCO -, - O -, - CO -, - CONH
COO -, - CONHCONH -, - CONH -, - SO 2 NH- or Represents

Preferred examples of b ₁ and b ₂ represent the same contents as those of a ₁ and a ₂ described above.

In the general formula (II b), Q ₀ is -CN, -CONH ₂ or Y represents a hydrogen atom, a halogen atom (eg, a chlorine atom, a bromine atom, etc.), an alkoxy group (eg, a methoxy group,
Ethoxy, propoxy, butoxy, etc.) or -CO
OZ ₃ (Z ₃ preferably represents an alkyl group having 1 to 8 carbon atoms, an aralkyl group having 7 to 12 carbon atoms or an aryl group).

The macromonomer (M) has the formula (IIa) and / or (II)
The polymer component represented by b) may be contained in two or more kinds.

Furthermore, in the case where X ₁ in the general formula (II a) is —COO—, in all polymer components in the macromonomer (M),
At least 30% by weight of a polymer component represented by the formula (IIa)
It is preferable to contain the above.

Further, in the macromonomer (M), the compound represented by the formula (IIa)
And / or (II b) are copolymerized as the second component together with the copolymer component represented by a polar group (-COOH group, -PO ₃ H
₂ groups, -SO ₃ H group, -OH group, -CHO group, acid anhydride containing group) as a component containing
Any vinyl compound containing the above polar group that can be copolymerized with the polymer component (IIa) and / or (IIb) can be used.・ Bandbook [Basic] "Baifukan (19
86). Specifically, acrylic acid,
α- and / or β-substituted acrylic acid (for example, α-acetoxy form, α-acetoxymethyl form, α (2-amino) ethyl form, α-chloro form, α-bromo form, α-fluoro form, α-
Tributylsilyl form, α-cyano form, β-chloro form, β
-Bromo form, α-chloro-β-methoxy form, α, β-dichloro form, etc.), methacrylic acid, itaconic acid, itaconic acid half esters, itaconic acid half amides, crotonic acid, 2
-Alkenylcarboxylic acids (eg 2-pentenoic acid,
2-Methyl-2-hexenoic acid, 2-octenoic acid, 4-methyl-2-hexenoic acid, 4-ethyl-2-octenoic acid, etc.), maleic acid, maleic acid half esters, maleic acid half amides, vinyl Benzenecarboxylic acid, vinylbenzenesulfonic acid, vinylsulfonic acid, vinylphosphonic acid, dicarboxylic acids, half-ester derivatives of vinyl groups or allyl groups of alcohols, and substituents of these carboxylic acid or sulfonic acid ester derivatives and amide derivatives Examples thereof include compounds containing the polar group.

In the above, R represents a hydrocarbon group or an -OR 'group (R' represents a hydrocarbon group), and R and R 'are preferably an aliphatic group having 1 to 22 carbon atoms (for example, a methyl group, an ethyl group, Propyl, butyl, hexyl, octyl, decyl, dodecyl, octadecyl, 2-chloroethyl, 2-methoxyethyl, 3-ethoxypropyl,
An allyl group, a crotonyl group, a butenyl group, a cyclohexyl group, a benzyl group, a phenethyl group, a 3-phenylpropyl group, a methylbenzyl group, a chlorobenzyl group, a fluorobenzyl group, a methoxybenzyl group, etc.), or an aryl group which may be substituted ( For example, phenyl group, tolyl group, ethylphenyl group, propylphenyl group, chlorophenyl group, fluorophenyl group, bromophenyl group, chloro-methyl-
Phenyl group, dichlorophenyl group, methoxyphenyl group, cyanophenyl group, acetamidophenyl group, acetylphenyl group, butoxyphenyl group, etc.) and the like.

Further, the cyclic acid anhydride-containing group is a group containing at least one cyclic acid anhydride, and examples of the cyclic acid anhydride contained include aliphatic dicarboxylic anhydride and aromatic dicarboxylic anhydride. Can be

Examples of the aliphatic dicarboxylic anhydride include a succinic anhydride ring, a glutaconic anhydride ring, a maleic anhydride ring,
Cyclopentane-1,2-dicarboxylic anhydride ring, cyclohexane-1,2-dicarboxylic anhydride ring, cyclohexene-1,2-dicarboxylic anhydride ring, 2,3-bicyclo [2.2.
2) octane dicarboxylic acid anhydride ring and the like, these rings, for example, a halogen atom such as chlorine atom, bromine atom, a methyl group, an ethyl group, a butyl group, even if substituted with an alkyl group such as a hexyl group Good.

Examples of the aromatic dicarboxylic anhydride include a phthalic anhydride ring, a naphthalene-dicarboxylic anhydride ring, a pyridine-dicarboxylic anhydride ring, a thiophene-dicarboxylic anhydride ring, and the like. Is, for example, a chlorine atom, a halogen atom such as a bromine atom, an alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group, a hydroxyl group, a cyano group, a nitro group, an alkoxycarbonyl group (for the alkoxy group, for example, Methoxy group, ethoxy group, etc.) may be substituted.

Examples of the OH group include vinyl group or allyl group-containing alcohols (for example, ester substituents such as allyl alcohol, methacrylic acid ester and acrylamide, compounds containing an -OH group in N-substituents), hydroxyphenol or Examples thereof include methacrylic esters or amides containing a hydroxyphenyl group as a substituent.

Examples of the monomer corresponding to the component containing a polar group are shown below, but the scope of the present invention is not limited thereto.

Here, in each of the following examples, Q ₁ is -H, -CH ₃ , -C
l, -Br, -CN, a -CH ₂ COOCH ₃ or -CH ₂ COOH indicated, Q ₂
Represents -H or -CH _3, j represents an integer of 2 to 18, k
Represents an integer of 2 to 5, h represents an integer of 1 to 4, and g represents an integer of 1 to 12.

_{(B-15) CH 2 =} CHCH 2 OCO (CH 2) g COOH (B-16) CH 2 = CHCH 2 h COOH (B-49) CH ₂ = CHCH _{2 h} OH (B-52) CH ₂ = CHCH _{2 h} OCO (CH _{2 j} OH The amount of the polar group-containing copolymer component in all the polymer components in the macromonomer (M) is preferably 0.5 to 50 parts by weight, more preferably 1 part by weight per 100 parts by weight of the total polymer components. ~ 40 parts by weight.

As the polymer component in the macromonomer (M), other polymer components other than the above may be contained. For example, acrylonitrile, methacrylonitrile, acrylamide Kind,
Methacrylamides, styrene and derivatives thereof (for example, vinyl toluene, chlorostyrene, dichlorostyrene,
Bromostyrene, hydroxymethylstyrene, N, N-dimethylaminomethylstyrene, etc., and heterocyclic vinyls (eg, vinylpyridine, vinylimidazole, vinylpyrrolidone, vinylthiophene, vinylpyrazole, vinyldioxane, vinyloxazine, etc.). .

When these other monomers are contained, the amount is preferably 1 to 20 parts by weight based on 100 parts by weight of all polymer components of the macromonomer (M).

Further, in the macromonomer (M), the above general formula (II
In addition to the copolymer component represented by a) or (II b) and the copolymer component containing a polar group, 1 to 20% by weight of a copolymer component containing a heat and / or photocurable functional group is further added. It is preferable to contain it in order to obtain higher mechanical strength.

“Thermal and / or photocurable functional group” refers to a functional group that causes a curing reaction of a resin by at least one of heat and light.

Specific examples of photocurable functional groups include Hideo Inui, Mototaro Nagamatsu, "Photosensitive Polymers" (Kodansha, published in 1977), Takahiro Kakuda, "New Photosensitive Resins" (publishing department of the Printing Society of Japan, published in 1981),
GEGreen and BPStrak, J.Macro.Sci.Reas.Macro Che
m., C21 (2), 187-273 (1981-82), CGRattey, "Ph
otopolymirization of Surface Cootings "(A. Wiley I
nter Science Pub. 1982), and functional groups used in conventionally known photosensitive resins and the like are used as photocurable resins.

Further, the “thermosetting functional group” in the present invention is a functional group other than the above-mentioned acidic group, and includes, for example, Tsuyoshi Endo, “Refinement of thermosetting polymer” (CMC Corporation, 1986), Yuji Harazaki, "Handbook of Latest Binder Technologies", Chapter II-I (Comprehensive Technology Center, published in 1985), Takayuki Otsu, "Synthesis and Design of Acrylic Resins and Development of New Applications" (Chubu Business Development Center Publishing Division,
1985), Emori Omori "Functional Acrylic Resin" (Techno System, 1985), and the like can use the functional groups of the references.

For example, -OH group, -SH group, -NH ₂ group, -NHR _a group [R _a represents a hydrocarbon group, for example, an optionally substituted alkyl group having 1 to 10 carbon atoms (e.g., methyl group, ethyl group, Propyl group, butyl group, hexyl group, octyl group, decyl group, 2
-Chloroethyl group, 2-methoxyethyl group, 2-cyanoethyl group, etc.), C4-8 optionally substituted cycloalkyl group (e.g., cycloheptyl group, cyclohexyl group, etc.), C7-12 substituted group. Aralkyl groups (eg, benzyl group, phenethyl group, 3-phenylpropyl group, chlorobenzyl group, methylbenzyl group, methoxybenzyl group, etc.), and optionally substituted aryl groups (eg, phenyl group, tolyl group, xylyl group) Chlorophenyl group, bromophenyl group, methoxyphenyl group, naphthyl group, etc.) -CONHCH ₂ OR _b [R _b represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms (for example, methyl group, ethyl group, propyl group, butyl group, hexyl group, octyl group, etc.)], -N =
C = O group and {D ₉ and d ₁₀ each represent a hydrogen atom, a halogen atom (eg, a chlorine atom, a bromine atom, etc.) or an alkyl group having 1 to 4 carbon atoms (eg, a methyl group, an ethyl group, etc.)} and the like. . As the polymerizable double bond group, specifically, CH ₂ 2CH—, CH ₂ CHCH—CH ₂ —, _{CH 2 = CH-CH 2 NHCO-} , CH 2 = CH-SO 2 -, CH 2 = CH-CO
_{-, CH 2 = CH-O-} , may be mentioned CH ₂ = CH-S-, and the like.

In the present invention, as a method of incorporating at least one functional group selected from the group of the curable functional group into the macromonomer (M), a method of introducing it into the polymer by a polymer reaction,
Alternatively, one or more monomers containing one or more of the functional groups and a monomer corresponding to the repeating unit of the general formula (IIa) or (IIb) and a "polar group-containing It can be obtained by a method such as a copolymerization reaction with a monomer corresponding to the “copolymer component”.

For the high-molecular reaction, a conventionally known low-molecular-weight synthesis reaction method can be used as it is. For example, the Chemical Society of Japan, “New Experimental Chemistry Course, Vol. 14, Synthesis and Reaction of Organic Compounds [I]-
[V] "(published by Maruzen Co., Ltd.)," Reactive Polymers "by Yoshio Iwakura and Keisuke Kurita, and the like, and are described in detail in publicly known literature and the like.

The macromonomer (M) used in the present invention is a random monomer comprising at least a repeating unit represented by the general formula (IIa) and / or (IIb) and a repeating unit containing a specific polar group as described above. The polymerizable double bond group represented by the general formula (I) is present only at one end of the polymer main chain,
It has a chemical structure which is directly bonded or is bonded by an arbitrary linking group. Formula (I) component and formula (II
Examples of the linking group that links the component (a) or (IIb) or the component containing a polar group include a carbon-carbon bond (single bond or double bond), a carbon-heteroatom bond (for example, an oxygen atom, Sulfur atom, nitrogen atom, silicon atom, etc.) and any combination of heteroatom-heteroatom bond atomic groups.

More specific linking groups include [R ₃₂ and R ₃₃ represent a hydrogen atom, a halogen atom (eg, fluorine atom, chlorine atom, bromine atom, etc.), cyano group, hydroxyl group, alkyl group (eg, methyl group, ethyl group, propyl group, etc.), etc.] , R ₃₄ and R _{35 each} represent a hydrogen atom, a single linking group selected from an atomic group such as a hydrocarbon group having the same content as Q ₁ in the formula (II a) or any combination thereof. Represents two or more linking groups constructed.

The weight average molecular weight of the macromonomer (M) of the present invention is 2
It is not more than × 10 ⁴ , preferably not less than 1 × 10 ³ .

When the weight average molecular weight of the macromonomer (M) exceeds 2 × 10 ⁴ , the copolymerizability with the monofunctional monomer containing a hydrophilic group-forming functional group decreases, which is not preferable. On the other hand, if the weight average molecular weight is too small, the effect of improving the electrophotographic properties of the photosensitive layer is reduced, so that the weight average molecular weight is preferably 1 × 10 ³ or more.

The macromonomer (M) used in the present invention can be produced by a conventionally known synthesis method. In particular,
A terminal obtained by radical polymerization using a polymerization initiator and / or a chain transfer agent containing a reactive group such as a carboxyl group, a carboxy halide group, a hydroxyl group, an amino group, a halogen atom, and an epoxy group in a molecule. It is synthesized by a method such as a radical polymerization method in which an oligomer having a reactive group is reacted with various reagents to form a macromonomer.

Specifically, P. Dreyfuss & RPQuirk, Encycl.Poly
m.Sci.Eng., 7 , 551 (1987), PFRempp, E.Franta,
Adv.Polym.Sci. 58 , 1 (1984), Yusuke Kawakami, Chemical Industry,
38 , 56 (1987), Yuya Yamashita, Polymer, 31 , 988 (198
2), Shiro Kobayashi, Polymer, 30 , Koichi Ito, Polymer Processing, 3
5 , 262 (1986), Takashiro Higashi, Takashi Tsuda, Functional Materials, 1987 ,
It can be synthesized according to the methods described in the reviews of Nos. 10 and 5 and the references and patents cited therein.

However, since the macromonomer (M) of the present invention contains a polar group as a component of its repeating unit, it is synthesized in consideration of, for example, the following.

As one of the methods, for example, as shown in the following reaction formula (I), radical polymerization and terminal reactive group are carried out by the above method using a monomer containing the polar group in the form of a functional group. Is to be introduced.

Polar group (-SO ₃ H groups contained randomly macromonomer (M) to be subjected to the present invention, -PO ₃ H ₂ group, -COO
H group, The protecting group reaction and the deprotection reaction (for example, hydrolysis reaction, hydrogenolysis reaction, oxidative decomposition reaction, etc.) of -OH group, -CHO group, acid anhydride-containing group) can be performed by a conventionally known method. . Specifically, JFWMcOmie, “Protec
tive Gvoups in Organic Chemistry ", Plenum Press (1
973), TWGreene, “Protective Gvoups in Organi
c Synthesis ", John Wiley & Sous (1981), Ryohei Oda" Polymer Fine Chemicals "Kodansha (1976), Yoshio Iwakura, Keisuke Kurita" Reactive Polymers "Kodansha (1977),
Berneretal, J. Radiation Curing, 1986, No. 10, P10,
JP-A-62-212669, JP-A-62-286064, JP-A-62-28664
No. 210475, JP-A-62-195684, JP-A-62-258476,
JP-A-63-260439, JP-A-1-63977, JP-A-1-7
It can be synthesized using the method described in No. 0767 and the like.

As another method, for example, as shown in the following reaction formula (II), after synthesizing an oligomer as described above, a “specific reactive group” bonded to one end of the oligomer is used.
Method of synthesizing by reacting with a reagent containing a polymerizable double bond group that reacts only with a "specific reactive group", utilizing the difference in reactivity between the polar group contained in the oligomer and the polar group contained in the oligomer Is.

As shown in the reaction formula (II), specific examples of combinations of the specific functional groups are shown in Table A as follows. However, the present invention is not limited to these, and it is important that macromonomerization can be achieved without protecting the polar group in the oligomer by utilizing the selectivity of the reaction in a normal organic chemical reaction. That should be done.

As the chain transfer agent that can be used, for example, the polar group, or a mercapto compound containing a substituent that can be subsequently induced to the 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, 3-mercapto-1,2-propanediol, 1-
Mercapto-2-propanol, 3-mercapto-2-
Butanol, mercaptophenol, 2-mercaptoethylamine, 2-mercaptoimidazole, 2-mercapto-3-pyridinol, etc.) or a disulfide compound which is an oxidized form of these mercapto compounds, or the above-mentioned polar group- or substituent-containing iodized alkyl compound ( Examples thereof include iodoacetic acid, iodopropionic acid, 2-iodoethanol, 2-iodoethanesulfonic acid, 3-iodopropanesulfonic acid and the like). Preferably, a mercapto compound is used.

Specific reactive group-containing polymerization initiators that can be used include, for example, 2,2′-azobis (2-cyanopropanol), 2,2′-azobis (2-cyanopentanol), 4,4 ′ -Azobis (4-cyanovaleric acid), 4,4'-
Azobis (4-cyanovaleric acid chloride), 2,2'-azobis [2- (5-methyl-2-imidazolin-2-yl) propane], 2,2'-azobis [2- (2-imidazoline-2) -Yl) propane], 2,2'-azobis [2
-(3,4,5,6-tetrahydropyrimidin-2-yl) propane], 2,2'-azobis {2- [1- (2-hydroxyethyl) -2-imidazolin-2-yl] propane}, 2,2'-azobis [2-methyl-N- (2-hydroxyethyl) -propionamide] and the like and derivatives thereof.

These chain transfer agents or polymerization initiators are each 0.1 to 15 parts by weight with respect to 100 parts by weight of all monomers, preferably
0.5 to 10 parts by weight.

Specific examples of the macromonomer (M) of the present invention include the following compounds. However, the scope of the present invention is not limited to these. In each of the following examples, Q ₂ represents -H or CH ₃ , and Q ₃ represents-
H, indicates -CH ₃ or -CH ₂ COOCH _3, R ₄₁ is -C _n H _{2n +} 1 _(n
Is an integer of _{1~18), - CH 2 C 6} H 5, (Y ₁ and Y ₂ each represent —H, —Cl, —Br, —CH ₃ , —COCH ₃ or —COOCH ₃ ), The illustrated, W ₁ is -CN, -OCOCH _3, shows a -CONH ₂ or -C ₆ H _5, W ₂ represents -Cl, -Br, -CN, or -OCH _3, alpha is 2
Represents an integer of 18, β represents an integer of 2 to 12, and γ represents 2 to 4
Indicates an integer.

Further, the graft copolymer of the present invention comprises, as well as the above-mentioned monofunctional monomer having a hydrophilic group-forming functional group and the above-mentioned macromonomer (M), other monomers other than these as copolymer components. May be contained.

For example, α-olefins, acrylonitrile, methacrylonitrile, acrylamide, methacrylamide,
Styrene, vinyl group-containing naphthalene compounds (eg, vinyl-naphthalene, 1-isopropenylnaphthalene, etc.),
Examples include compounds such as a vinyl group-containing heterocyclic compound (for example, vinylpyridine, vinylpyrrolidone, vinylthiophene, vinyltetrahydrofuran, vinyl-1,3-dioxolan, vinylimidazole, vinylthiazole, vinyloxazoline, and the like).

The polymer component corresponding to the hydrophilic group-forming functional group-containing monomer (A) in the graft copolymer of the present invention accounts for 30 to 90% by weight, particularly 40 to 80% by weight of the whole polymer. Is preferred. The polymer component corresponding to the monofunctional macromonomer (M) in the total polymer is 10 to 70% by weight, particularly 20% by weight.
Preferably it is 6060% by weight. Further, it is preferable that other polymer components other than the above do not exceed at most 30% by weight.

The weight average molecular weight of the copolymer is 10 ³ to 10 ⁶ , especially 5
It is preferably from × 10 ^{3 to} 5 × 10 ⁵ .

When the content of the monomer (A) is 30% by weight or less or the content of the macromonomer (M) is 70% by weight or more, the effect of improving the water retention when desensitized and printed as an offset printing original plate is diminished.

On the other hand, when the content of the monomer (A) is 90% by weight or more or the content of the macromonomer (M) is 10% by weight or less, the effect of improving water retention cannot be maintained when the number of printed sheets in printing increases.

The binder resin in the lithographic printing plate precursor of the present invention may be the graft copolymer of the present invention alone, or may be used in combination with other conventionally known resins.

Examples of the resin used in combination include an alkyd resin, a vinyl acetate resin, a polyester resin, a styrene-butadiene resin, and an acrylic resin as mentioned above.
Specifically, Ryuji Kurita, Jiro Ishiwatari, Polymer, Vol. 17,
278 (1968), Harumiya Miyamoto, Hidehiko Takei, Imaging, 1973 (No. 8), page 9 and other well-known materials mentioned in the review.

Preferably, a random copolymer group containing, as a polymer component, methacrylate known as a binder resin of an electrophotographic photoreceptor using photoconductive zinc oxide as an inorganic photoconductor is cited as one of them. For example, Japanese Patent Publication No. 50-2242
No., JP-B-50-31011, JP-A-50-98324, JP-A-50-98324
-98325, JP-B-54-13977, JP-B-59-35013,
Resins described in JP-A-54-20735 and JP-A-57-202544 are exemplified.

Further, it is composed of a random copolymer having a weight average molecular weight of 20,000 or less and a methacrylate and an acid group-containing monomer, and another resin having a weight average molecular weight of 30,000 or more, or a compound which is cured by heat and / or light. Binder resin (for example, JP-A-63-220148, JP-A-63-220149, JP-A-2-3486)
0, JP-A-2-40660, JP-A-2-53064, JP-A-1-102573, etc.). Alternatively, a polymer having a weight average molecular weight of 20,000 or less and containing a methacrylate component and having an acidic group at one end of the polymer main chain, and another resin having a weight average molecular weight of 30,000 or less or a heat And / or a binder resin composed of a combination with a light-curable compound (for example, JP-A-1-169455 and 1-280761).
No. 1, No. 1-214865, No. 2-874, and Japanese Patent Application No. 63-221485.
No. 63-220442, Japanese Patent Application No. 63-220441, etc.) may be used in combination.

When the graft type copolymer of the present invention and the above-mentioned other binder resin are used in combination, the use ratio thereof can be used at any ratio, but preferably 100 parts by weight of the total binder resin, The content is 0.5% to 20% by weight, particularly 1% to 10% by weight.

In particular, when the resin of the present invention is used in combination with another binder resin (especially one that satisfies electrophotographic properties corresponding to semiconductor laser light), the resin of the present invention is concentrated on the surface portion of the photoconductive layer. Therefore, it was found that a very small amount of use was sufficient.

As a result, while maintaining excellent electrophotographic properties,
The resin of the present invention, which expresses a hydrophilic group by desensitization treatment, is efficiently present on the surface portion, the hydrophilicity of the binder resin is effectively achieved, and the image quality and background stain of printed matter can be significantly improved. Became.

That is, the graft copolymer of the present invention comprises a polymer component containing a fluorine atom and / or a silicon atom (part: segment A) and a polymer component corresponding to the macromonomer (M) (part: segment B). However, when the photoconductive layer is formed, since the segment A portion has remarkable lipophilicity, a transition phenomenon occurs on the surface portion of the photoconductive layer, and despite the small amount of use as described above, It is presumed that the graft copolymer of the present invention can be concentrated and present on the surface portion. Further, the copolymer of the present invention containing the segment A containing a hydrophilic group-forming functional group is hydrolyzed or hydrogenolyzed or photolyzed by a desensitizing solution or a fountain solution used for printing to form a hydrophilic group. I do.

Therefore, as described above, when the copolymer is used as a binder resin for a lithographic printing plate precursor, the hydrophilicity of the non-image portion which is made hydrophilic by the desensitizing solution is changed to the above-mentioned hydrophilic group generated in the resin. Is further enhanced by the concentrated presence of the segment A portion containing on the surface portion, the lipophilicity of the image portion and the hydrophilicity of the non-image portion become clear, and the printing ink adheres to the non-image portion during printing. To prevent

On the other hand, as described above, since the resin of the present invention containing a hydrophilic group formed by decomposition by fountain solution during etching and printing on a printing machine is a graft copolymer, the macromonomer (M The segment B portion corresponding to the portion B) is lipophilic, and the interaction with the zinc oxide and / or other binder resin in the photoconductive layer is significantly increased, so that the segment B portion acts as an anchor. Has the effect of preventing dissolution and elution. Therefore, even if a large number of sheets are printed, the hydrophilicity of the non-image area is maintained, and high printing durability can be achieved.

In a more preferred embodiment, a binder resin that shows good electrophotographic properties even when the environmental conditions fluctuate or shows good electrophotographic properties even in a scanning exposure system using a semiconductor laser beam as a light source is excellent. The effect of improving the hydrophilicity by using the graft type copolymer of the present invention in a photoconductive layer exhibiting electrophotographic properties and having good reproducibility of the original image of a copied image in a usage amount that does not impair these properties at all. It is possible to print a large number of prints of clear image quality without background contamination even when printing conditions such as enlargement of a printing machine or fluctuation of printing pressure become severe.

The inorganic photoconductive material used in the present invention is a photoconductive zinc oxide, and titanium oxide, zinc sulfide, cadmium sulfide, cadmium carbonate, zinc selenide, cadmium selenide, and tellurium selenide as other inorganic photoconductors. , Lead sulfide or the like may be used in combination. However, these other photoconductive materials comprise up to 40% by weight of the photoconductive zinc oxide, preferably up to 20% by weight.

If the content of the other photoconductive material exceeds 40% by weight, the effect of improving the hydrophilicity of the non-image portion as a lithographic printing original plate is diminished.

The total amount of the binder resin used for the inorganic photoconductive material is 10 to 100 parts by weight, preferably 15 to 50 parts by weight, based on 100 parts by weight of the photoconductor.

In the present invention, various dyes can be used as spectral sensitizers as needed. For example, Harumiya Miyamoto, Hidehiko Takei, Imaging 1973 (No.8) page 12, CJ Young, R
CA Review 15, 469 (1954), Kouhei Kiyota, The Institute of Electrical Communication, J 63-C (No. 2), 97 (1980), Yuji Harasaki, etc., Journal of Industrial Chemistry 66 78 and 188 (1963), Tadaaki Tani. , Journal of Japan photographic Society 35, 208 (1972) carbonium-based dyes review references such as, diphenylmethane dyes, triphenylmethane dyes,
Xanthene dyes, phthalein dyes, polymethine dyes (for example, oxonol dyes, merocyanine dyes, cyanine dyes, rhodacyanine dyes, styryl dyes, and the like), phthalocyanine dyes (which may contain metals), and the like.

More specifically, those using mainly carbonium dyes, triphenylmethane dyes, xanthene dyes, and phthalein dyes are described in JP-B-51-452,
-90334, JP-A-50-114227, JP-A-53-39130,
JP-A-53-82353, U.S. Pat. No. 3,052,540, U.S. Pat. No. 4,054,450, and JP-A-57-16456 are examples.

Examples of polymethine dyes such as oxanol dyes, merocyanine dyes, cyanine dyes, and rhodacyanine dyes include F.I.
M. Hamer `` The Cyanine Dyes and Related Compounds ''
Can be used, more specifically, more specifically,
U.S. Patent 3,047,384, U.S. Patent 3,110,591, U.S. Patent 3,121,008, U.S. Patent 3,125,447, U.S. Patent 3,128,179, U.S. Patent 3,132,942, U.S. Pat.
622,317, UK Patent 1,226,892, UK Patent 1,309,
No. 274, British Patent No. 1,405,898, JP-B-48-7814, JP-B-55-18892 and the like.

Further, as a polymethine dye for spectrally sensitizing the near infrared to infrared light region having a long wavelength of 700 nm or more, JP-A-47-840, JP-A-47-44180, JP-B-51-41061, 1949-5034
No., JP-A-49-45122, JP-A-57-46245, JP-A-56
No. -35141, JP-A-57-157254, JP-A-61-26044,
JP-A-6-27551, US Pat. No. 3,619,154, US Pat. No. 4,175,956, “Research Disclosure” 1982, 21
6, pages 117 to 118, and the like. The photoreceptor of the present invention is excellent in that even when various sensitizing dyes are used in combination, the performance is hardly changed by the sensitizing dye.
Further, if necessary, various conventionally known additives for an electrophotographic photosensitive layer such as a chemical sensitizer can be used in combination.
For example, the review mentioned above: Imaging 1973 (No. 8) No. 12
Electron-accepting compounds (for example, halogen, benzoquinone, chloranil, acid anhydrides, organic carboxylic acids, etc.) as a reference article, Hiroshi Komon, et al., "Recent Development and Practical Use of Photoconductive Materials and Photoconductors" Chapters 4 to 6: Polyalalkane compounds, which are the reference articles of the Japanese Science Information Publishing Co., Ltd. (1986),
Examples thereof include hindered phenol compounds and p-phenyldiamine compounds.

The amounts of these various additives are not particularly limited, but are usually 0.0001 to 2.0 parts by weight based on 100 parts by weight of the photoconductor.

The thickness of the photoconductive layer is preferably from 1 to 100 μm, particularly preferably from 10 to 50 μm.

When a photoconductive layer is used as the charge generation layer of the photoreceptor having the charge generation layer and the charge transport layer, the thickness of the charge generation layer is preferably 0.01 to 1 μm, particularly preferably 0.05 to 0.5 μm.

Examples of the charge transport material of the laminated photoreceptor include polyvinyl carbazole, oxazole dyes, pyrazoline dyes, and triphenylmethane dyes. The thickness of the charge transport layer is preferably 5 to 40 μm, particularly preferably 10 to 30 μm.

Typical resins used for forming the charge transport layer include polystyrene resin, polyester resin, cellulose resin, polyether resin, vinyl chloride resin, vinyl acetate resin, vinyl chloride-vinyl chloride copolymer resin, and polyacryl resin. ,
A thermoplastic resin and a curable resin such as a polyolefin resin, a urethane resin, an epoxy resin, a melamine resin, and a silicone resin are appropriately used.

The photoconductive layer according to the present invention can be provided on a conventionally known support. Generally speaking, the support of the electrophotographic photosensitive layer is preferably conductive, and as the conductive support, for example, a substrate such as metal, paper or plastic sheet is impregnated with a low resistance substance as in the conventional case. Those which have been subjected to a conductive treatment, such as those which have been subjected to a conductivity treatment, those which are provided with conductivity on the back surface of the substrate (the surface opposite to the surface on which the photosensitive layer is provided), and have at least one layer coated for the purpose of preventing curling, Water-resistant adhesive layer provided on the surface of the body, at least one precoat layer provided on the surface layer of the support, if necessary, laminated electroconductive plastic substrate such as Al laminated on paper Those that have been made can be used.

Specifically, as an example of a conductive substrate or a conductive material, Yukio Sakamoto, Electrophotography, 14, (No. 1), p2-11 (197)
5), Hiroyuki Moriga, “Chemistry of Introductory Special Papers” Polymer Publishing Association (1
975), MF Hoover, J. Macromol. Sci. Chem. A-4 (6),
Those described in pages 1327 to 1417 (1970) and the like are used.

A printing plate using the lithographic printing plate precursor of the present invention is prepared by forming a copy image on the electrophotographic printing plate having the above-described structure by a conventional method, and then subjecting the non-image portion to desensitization treatment. In the desensitization treatment provided in the present invention, both the desensitization reaction of zinc oxide (hereinafter referred to as A reaction) and the desensitization reaction of the resin (hereinafter referred to as B reaction) proceed. Examples of the method of desensitization include a method of performing an A reaction treatment and then a B reaction treatment, a method of performing a B reaction treatment and then performing an A reaction treatment,
Alternatively, there is a method of simultaneously treating the A reaction and the B reaction, and any of these may be used.

As a method for desensitizing zinc oxide, any of conventionally known treatment solutions can be used. For example, Japanese Patent Application Laid-Open No. Sho 62-62 uses a ferrocyanide compound as a main agent for desensitization.
239158, 62-292492, 63-99993, 63-99994, JP-B-40-7334, JP-B45-33683, JP-A-57-107889, JP-B-46-21244, 44-9045, 47-32681 , 55-9315,
JP-A-52-101102 and the like.

In addition, using a phytic acid-based compound as a main agent,
10003, 53-83805, 53-83806, 53-127002, 5
4-44901, 56-2189, 57-2796, 57-20394, 5
Nos. 9-207290, JP-B-38-96 using a water-soluble polymer capable of forming a metal chelate as a main component.
65, 39-22263, 40-763, 43-28404, 47-296
42, JP-A-52-126302, JP-A-52-134501, JP-A-53-49506,
JP-A-53-59502, JP-A-53-104302, etc.,
JP-A-53-1043 using a metal complex compound as a main component
01, JP-B-55-15313, JP-B-54-41924, or those using inorganic and organic acid compounds as main agents,
Examples thereof include those described in JP-A-51-118501 and JP-A-56-111695.

On the other hand, as a method for desensitizing the resin of the present invention containing a functional group which generates a hydrophilic group by decomposition of the present invention (that is, development of hydrophilicity), a method of hydrolyzing by passing through a treatment liquid or a method of irradiating light There is a method of processing and decomposing.

The treatment solution is an aqueous solution containing a pH adjuster for adjusting the pH to a predetermined value. The set pH differs depending on the type of the hydrophilic group-forming functional group of the present invention, and can be appropriately used from pH 1 to 13.

Further, other compounds may be contained. For example, 1 to 50 parts by weight of an organic solvent soluble in water may be contained in 100 parts by weight of water. Examples of such water-soluble organic solvents include alcohols (methanol, ethanol, propanol, propargyl alcohol, benzyl alcohol, phenethyl alcohol, etc.), ketones (acetone, methyl ethyl ketone, acetophenone, etc.), ethers (dioxane, Trioxane, tetrahydrofuran, ethylene glycol, propylene glycol, ethylene glycol monomethyl ether, propylene glycol monomethyl ether, tetrahydropyran, etc., amides (dimethylformamide, dimethylacetamide, etc.), esters (methyl acetate, ethyl acetate, ethyl formate, etc.), etc. These may be used alone or in combination of two or more.

Further, 0.1 to 20 parts by weight of a surfactant may be contained in 100 parts by weight of water. Examples of the surfactant include conventionally known anionic, cationic or nonionic surfactants. For example, compounds described in Hiroshi Horiguchi "New Surfactants" Mitsui Publishing Co., Ltd. (1975), Ryohei Oda, Kazuhiro Teramura, "Synthesis of Surfactants and Their Applications" Maki Shoten (1980), etc. Can be used.

The scope of the present invention is not limited to the specific compound examples described above.

The conditions of the treatment are preferably a temperature of 15 to 60 ° C. and an immersion time of 10 seconds to 5 minutes.

As a method of decomposing a specific functional group in the resin of the present invention by light irradiation, a step of irradiating light with "chemically active light" between any of after obtaining a toner image in plate making may be included. I just need. That is, after the electrophotographic development, light irradiation may be performed also to fix the toner image at the time of fixing, or after fixing by other conventionally known fixing methods, for example, heat fixing, pressure fixing, solvent fixing, etc. Irradiation is performed.

The “chemically active light” used in the present invention may be any of visible light, ultraviolet light, far ultraviolet light, electron beam, X-ray, γ-ray, α-ray, etc., and preferably includes ultraviolet light. More preferably, it can emit light in a wavelength range of 310 nm to 500 nm, and generally a high-pressure or ultra-high-pressure mercury 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.

(Examples) Examples of the present invention will be described below, but the contents of the present invention are not limited thereto.

Synthesis Example of Macromonomer (M) 1: MM-1 90 g of ethyl methacrylate, 10 g of 2-hydroxyethyl methacrylate, 5 g of thioglycolic acid and 200 of toluene
g of the mixed solution was heated to a temperature of 75 ° C. while stirring under a nitrogen stream. 2,2'-azobisisobutyronitrile (abbreviation)
(AIBN) 1.0 g and reacted for 8 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 n-hexane 2 to obtain 82 g of a white powder. The weight average molecular weight of the polymer was 3.8 × 10 ³ .

Synthesis Example 2 of Macromonomer (M): A mixed solution of 90 g of MM-2 butyl methacrylate, 10 g of methacrylic acid, 4 g of -mercaptoethanol and 200 g of tetrahydrofuran was heated to a temperature of 70 ° C under a nitrogen stream. AIBN 1.2g
Was added and reacted for 8 hours.

Next, the reaction solution was cooled in a water bath to a temperature of 20 ° C.,
Triethylamine (10.2 g) was added, and methacrylic acid chloride (14.5 g) 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, it is dropped into water 1 with stirring (about 10 minutes)
After stirring for 1 hour as it was and standing, water was removed by decantation. After washing twice with water, the residue was dissolved in 100 ml of tetrahydrofuran and reprecipitated in petroleum ether 2. The precipitate was collected by decantation and dried under reduced pressure. The yield of the obtained viscous material was 65 g, and the weight average molecular weight was 5.6 × 10 ³ .

Synthesis Example 3 of Macromonomer (M): MM-3 A mixture of 95 g of benzyl methacrylate, 5 g of 2-phosphonoethyl methacrylate, 4 g of 2-aminoethylmercaptan and 200 g of tetrahydrofuran is heated to 70 ° C. under stirring under a nitrogen stream. did.

Add 1.5g of AIBN and let it react for 4 hours.
0.5 g was added and reacted for 4 hours. Next, the reaction solution was cooled to a temperature of 20 ° C.
Stirred at 0-25 ° C for 1 hour. Next, 1.0 g of t-butylhydroquinone was added, and the mixture was stirred at a temperature of 50 to 60 ° C for 4 hours. After cooling, the reaction mixture was added dropwise to water 1 while stirring for about 10 minutes, stirred for 1 hour and allowed to stand, and water was removed by decantation. After repeating the washing with water twice more, it was dissolved in 100 ml of tetrahydrofuran and reprecipitated in petroleum ether 2. The precipitate was collected by decantation and dried under reduced pressure. The yield of the obtained viscous material is
The weight average molecular weight was 7.4 × 10 ³ at 70 g.

Synthesis Example 4 of Macromonomer (M): MM-4 2-Chlorophenylmethacrylate 95 g, monomer 5 g of the following structure (I), thioglycolic acid 4 g and toluene 20
0 g of the mixed solution was heated to a temperature of 70 ° C. under a nitrogen stream. AI
1.5 g of BN was added and reacted for 5 hours, and 0.5 g of AIBN was further added and reacted for 4 hours. Next, glycidyl methacrylate 12.4
g, 1.0 g of N, N-dimethyldodecylamine and 1.5 g of t-butylhydroquinone were added and reacted at 110 ° C. for 8 hours.
After cooling, the reaction mixture was mixed with 3 g of p-toluenesulfonic acid, 90 g
The solution was added to 100 ml of a vol% aqueous tetrahydrofuran solution and stirred at a temperature of 30 to 35 ° C for 1 hour. Water / ethanol [(1 /
3) The mixture was reprecipitated in a mixed solution 2 (volume ratio), and the precipitate was collected by decantation. This precipitate was dissolved in 200 ml of tetrahydrofuran and n-hexane 2 was added.
It was re-precipitated in the inside to obtain 58 g of powder. Weight average molecular weight is 7.6 × 10
^{Was 3} .

Synthesis Example 5 of Macromonomer (M): MM-5 2,6-dichlorophenyl methacrylate 95 g, 3-
A mixed solution of 5 g of (2′-nitrobenzyloxysulfonyl) propyl methacrylate, 150 g of toluene and 50 g of isopropyl alcohol was heated to a temperature of 80 ° C. under a nitrogen stream. 2,2'-azobis (2-cyanovaleric acid) (abbreviation: AC
V.) 5.0 g was added and reacted for 5 hours, and ACV 1.0 g was further added and reacted for 4 hours. After cooling, the reaction product was reprecipitated in methanol 2, and the powder was collected by filtration and dried under reduced pressure.

50 g of the above powder, 14 g of glycidyl methacrylate, N, N-
Dimethyl dosylamine 0.6g, t-butyl hydroquinone
A mixture of 1.0 g and 100 g of toluene was stirred at a temperature of 110 ° C. for 10 hours. After cooling to room temperature, the mixture was irradiated with light for 1 hour with stirring using a high-pressure mercury lamp of 80 W. Thereafter, the reaction mixture was reprecipitated in methanol 1, and the powder was collected by filtration and dried under reduced pressure.
The yield was 34 g and the weight average molecular weight was 7.3 × 10 ³ .

Synthesis Example 6 of Macromonomer (M): MM-6 60 g of metal methacrylate, 30 g of methyl acrylate,
A mixed solution of 10 g of the monomer of the following structure (II), 3 g of β-mercaptopropionic acid and 200 g of tetrahydrofuran was heated to a temperature of 70 ° C under a nitrogen stream. AIBN 1.5 g was added and reacted for 4 hours, and AIBN 0.5 g was further added and reacted for 3 hours. Then, the reaction mixture was cooled to 25 ° C., 10 g of 2-hydroxyethyl methacrylate was added thereto, and under stirring, 15 g of dicyclohexylcarbodiimide (DCC), 0.4 g of 4- (N, N-dimethylamino) pyridine and 38 g of methylene chloride were added. The mixed solution was added dropwise over 1 hour and then stirred for 4 hours.

Next, 5 g of a 30% hydrogen chloride ethanol solution and 5 g of water were added, and the mixture was stirred for 1 hour as it was. After separating the insoluble matter, the solution was reprecipitated in methanol 1.5, and the precipitate was collected and dried. The w of the obtained polymer was 7.5 × 10 ³ .

Synthesis Examples 7 to 12 of Macromonomer (M): MM-7 to 12 Macromonomers shown in Table 1 below were synthesized by replacing the monomers used in the same manner as in Synthesis Example 6 of macromonomer (M). The resulting macromonomer has a w of 6.0 × 10 ³ to 8 × 10
It was in the range of ³ ).

Binder Resin Production Example 1: GP-1 A mixed solution of 70 g of the following compound (A-1), 30 g of Macromonomer (MM-1) of Synthesis Example 1 of macromonomer and 200 g of toluene was heated to a temperature of 75 ° C. under a nitrogen stream. Warmed. In addition, A.
1.0 g of IBN was added and reacted for 4 hours, and 0.6 g of AIBN was further added and reacted for 4 hours.

The w of the obtained polymer was 4.5 × 10 ⁴ .

Production Example 2 of Binder Resin: GP-2 A mixed solution of 85 g of the following compound (A-2), 15 g of macromonomer (MM-2) of Synthesis Example 2 of macromonomer and 200 g of tetrahydrofuran was added to a temperature of 60 ° C. under a nitrogen stream. Warmed.
2,2'-azobisvaleronitrile (abbreviation: ABVN)
1.5 g was added and reacted for 4 hours. Further, 0.8 g of ABVN was added and reacted for 4 hours.

W of the obtained polymer was 5.0 × 10 ⁴ .

Binder Resin Production Example 3: GP-3 A mixed solution of the following compound (A-3) 80 g, macromonomer Synthesis Example 3 macromonomer (MM-3) 20 g and toluene 200 g was prepared. The polymerization reaction was carried out in the same manner as in Example 1. W of the obtained polymer is 5.3 × 10 ⁴
Met.

Binder Resin Production Examples 4 to 10: GP-4 to GP-10 In Binder Resin Production Example 3, 80 g of compound (A-3) was used.
And each polymer was produced in the same manner as in Production Example 3 except that each compound shown in Table 2 below was used instead of 20 g of the macromonomer (MM-3). W of each polymer is 4.5 × 10 ⁴
It was ˜6 × 10 ⁴ .

Example 1 2 g (as solid content) of the binder resin (GP-1) of the present invention,
38 g of binder resin (B-1) having the following structure, photoconductive zinc oxide 2
A mixture of 00 g, uranine 0.03 g, rose bengal 0.06 g, tetrabromophenol blue 0.02 g, maleic anhydride 0.20 g and toluene 300 g was homogenized (manufactured by Nippon Seiki Co., Ltd.) at a rotation speed of 1 × 10 ⁴ rpm. Dispersed for 10 minutes. The photosensitive layer forming dispersion dry coverage to the conductive treated paper was coated with a wire bar so as to 20g / m ^2, 100
Dried for 3 minutes at ° C. Then, it was left standing in a dark place at 20 ° C. and 65% RH for 24 hours to prepare an electrophotographic photosensitive material.

Example 2 In place of 38 g of the binder resin (B-1) in Example 1, 5.7 g of the binder resin (B-2) and 32.3 g of the binder resin (B-3) having the following structures were used, An electrophotographic photosensitive material was produced in the same manner as in Example 1.

In the above Example 1, two types of comparative photosensitive materials A and B were prepared by replacing the photosensitive layer formed product with the following copolymer.

Comparative photosensitive material A: An electrophotographic photosensitive material was produced in the same manner as in Example 1, except that only 40 g of the resin (B-1) was used as the binder resin.

Comparative photosensitive material B: An electrophotographic photosensitive material was operated in the same manner as in Example 1, except that 2 g of the binder resin (B-4) having the following structure and 38 g of the resin (B-1) were used as the binder resin. Was prepared.

The film properties (surface smoothness), electrostatic properties, imaging properties, desensitizing property of the photoconductive layer (expressed by the contact angle of the photoconductive layer with water after desensitizing treatment) and printing of these photosensitive materials. The sex was examined. The printability is obtained by exposing and developing an image on the fully automatic plate-making machine ELP-404V (manufactured by Fuji Photo Film Co., Ltd.) using the developer ELP-T to form an image, followed by desensitizing treatment. It was examined by using a lithographic printing plate (note that a Hamada Star 800SX type manufactured by Hamada Star Co., Ltd. was used as a printing machine).

 Table 3 summarizes the above results.

The modes of implementation of the evaluation items shown in Table 3 are as follows.

Note 1) Smoothness of photoconductive layer: The obtained photosensitive material was measured for its smoothness (sec / cc) using a Beck smoothness tester (manufactured by Kumagaya Riko Co., Ltd.) under the condition of an air capacity of 1 cc. It was measured.

Note 2) Electrostatic properties: Paper analyzer (Kawaguchi Electric Co., Ltd. paper analyzer) in a dark room at a temperature of 20 ° C and 65% RH.
SP-428 type) using a left for 10 seconds After the 20 seconds corona discharge at -6 KV, and measuring the surface potential V ₁₀ at this time. Next, the potential V ₇₀ after standing still in the dark for 60 seconds was measured, and the potential retention after dark decay for 60 seconds, that is, the dark decay retention rate [DRR (%) was (V ₇₀ / V ₁₀ ) × 100] (%)]. Further, the followed photoconductive layer surface after charging the photoconductive layer surface to -400V irradiated with visible light illumination 2.0 lux by corona discharge, the surface potential V ₁₀ is calculated the time to decay to 1/10, From this, the exposure amount E _1/10 (looks / second) is calculated.

Similarly it obtains the time until V ₁₀ is attenuated to 1/100 to calculate therefrom exposure 1/100 (lux · sec).

Note 3) Imaging: Each photosensitive material and fully automatic plate-making machine ELP404V (manufactured by Fuji Photo Film Co., Ltd.) are left at room temperature and humidity (20 ° C, 65%) for one day and then plate-made to form a copy image. Then, the image (fog, image room) of the obtained copy original plate is visually observed (this is referred to as I). The image quality II of the copied image is tested by the same method as the above I, except that the plate making is performed at high temperature and high humidity (30 ° C., 80%).

Note 4) Raw plate water retention: Each photosensitive material itself (original plate that is not prepressed: abbreviated as raw plate) Fuji Film Co., Ltd. desensitizing solution: An aqueous solution prepared by doubling ELP-EX with distilled water. After passing through the etching machine once, it was immersed in an aqueous solution adjusted to pH 11.0 with a buffer for 30 seconds.

Next, these plates were printed using a Hamadastar 800SX manufactured by Hamadastar Co., Ltd., and the fiftyth printed matter from the start of printing was visually evaluated for the presence of background stain.

Note 5) Background stain on printed matter: After making each photosensitive material in the same manner as in Note 3) above, make a plate through the etching machine once using ELP-EX, and adjust the pH 11 used in Note 4) above. Immersed in an aqueous solution of 0.1 for 30 seconds.

These offset master plates subjected to the desensitization treatment were printed, and the number of printed sheets until the background stain on the printed matter could be visually discriminated was examined.

The electrostatic characteristics of the present invention and Comparative Example A were good, and the actual imaging performance and the copied image were all clear. Further, the photoconductor of Example 2 of the present invention was more excellent in both electrostatic characteristics and imaging property. In Comparative Example B, the environmental conditions were (30
(° C, 80% RH), degradation was observed.

When each of these photoreceptors was desensitized, and the degree of hydrophilicity of the non-image area was evaluated. In Comparative Examples A and B, background stain due to adhesion of printing ink was remarkable, and the non-image area was sufficiently hydrophilized. Not done. Furthermore, after actually making the plate, the plate was desensitized and printed, and the lithographic plate of the present invention showed 5000 to 5,000 prints with no clear image and no clear image.
6000 sheets were obtained.

On the other hand, in Comparative Examples A and B, the background stain in the non-image area became remarkable after printing.

As described above, the electrophotographic lithographic printing plate precursor of the present invention provides good image-capturing properties even when the environmental conditions fluctuate, provides sufficient non-image area hydrophilicity, and does not generate background fog. Was.

Examples 3 to 11 Photosensitive materials were prepared in the same manner as in Example 2 except that 2 g of each resin (as solid content) shown in Table 4 below was used instead of 2 g of the binder resin (GP-1) in Example 2. It was made.

The electrostatic properties and printing properties were evaluated by operating in the same manner as in Example 2.

For each photosensitive material, both the electrostatic characteristics and the imaging properties were the same as those in Example 2.
It showed almost the same characteristics as.

In addition, when the performance of the offset lithographic original plate was evaluated by desensitizing treatment, the water retention of the raw plate was good, and the printing result after the actual plate making could print 6,000 sheets.

Example 12 and Comparative Examples C to D 3 g (as solid content) of the binder resin (GP-6) of the present invention,
4.6g of resin (B-5) having the following structure, resin (B-
6) A mixture of 32.4 g, zinc oxide 200 g, cyanine dye [A] 0.018 g having the following structure and toluene 300 g was dispersed in a homogenizer at a rotation speed of 1 × 10 ⁴ rpm for 10 minutes to prepare a photosensitive layer forming material. Then, apply this to a conductive-treated paper with a wire bar so that the dry adhesion amount will be 20 g / m ^2, and then 100 ℃
For 3 minutes at 24 ° C in the dark at 20 ° C and 65% RH.
After standing for a period of time, an electrophotographic photosensitive material was prepared.

Comparative Example C: A light-sensitive material was prepared in the same manner as in Example 12, except that 3 g of the resin (B-4) was used instead of 3 g of the resin (GP-6) in Example 12.

Comparative Example D: 3 g of the binder resin (GP-6) in Example 12 (B-5)
Instead of 4.6 g and 32.4 g of (B-6), resin (B-4) 2
A light-sensitive material was prepared in the same manner as in Example 12, except that 4 g, 4.6 g of (B-5) and 11.4 g of (B-6) were used.

The film properties (surface smoothness), electrostatic properties, imaging properties, and electrostatic characteristics of the photosensitive material when the environmental conditions were set to 30 ° C. and 80% RH were examined. Furthermore, when these photosensitive materials are used as an offset master master, the photoconductive layer is rendered insensitive to desensitization (expressed by the contact angle of the photoconductive layer with water after the desensitization treatment) and printable (ground stain, Printing durability).

 The above results are summarized in Table-5.

In the evaluation items shown in Table 5, the smoothness of the photoconductive layer and the background stain of the printed matter were the same as in Example 1.

The electrostatic characteristics and the imaging properties were implemented in the following manner.

Note 5) Electrostatic characteristics: Paper analyzer (Paper analyzer manufactured by Kawaguchi Electric Co., Ltd.) in a dark room at a temperature of 20 ° C. and 65% RH.
After the 20 seconds corona discharge -6kV with SP-428 type), allowed to stand for 10 seconds to measure the surface potential V ₁₀ at this time.
Then, the potential V ₁₉₀ after standing still in the dark for 180 seconds was measured, and the retention of the potential after dark decay for 180 seconds, that is, the dark decay retention DRR (%) was [(V ₁₉₀ / V ₁₀ ) × 100
(%)].

After charging the surface of the photoconductive layer to −400 V by corona discharge, the surface is irradiated with monochromatic light having a wavelength of 780 nm, and the surface potential (V ₁₀ ) is reduced.
The time required to decay to 1/10 is determined, and the exposure E
Calculate _1/10 (erg / cm ² ).

The time required for the surface potential (V ₁₀ ) to decay to 1/100 is determined, and the exposure amount E _1/100 (erg / cm ² ) is calculated from this.

Note 6) Imaging performance: Each photosensitive material was left for one day and night under the following environmental conditions. Next, charged at −5 kV, using a gallium-aluminum-arsenic semiconductor laser (oscillation wavelength: 780 nm) with a 2.0 mW output as a light source, a pitch of 25 μm and a scanning speed on the surface of the photosensitive material under an irradiation amount of 45 erg / cm ² After exposure at a speed of 330 m / sec, development was performed using ELP-T (manufactured by Fuji Photo Film Co., Ltd.) as a liquid developer, and the copied image (fog, image quality) obtained by fixing was visually evaluated. .

The photoreceptor of the present invention was excellent in both electrostatic characteristics and image-capturability. In Comparative Example C, E _1/100 was slightly lowered in electrostatic characteristics. However, depending on the type of image to be copied (for example, if it is limited to a text document or a document with a high white background), the imaging performance can be practically used. On the other hand, in Comparative Example D, the electrostatic characteristics were deteriorated, and the influence was remarkably affected especially when environmental conditions fluctuated.
Ground fog and broken character thin lines occurred.

On the other hand, the original plate subjected to desensitization treatment is only the one of the present invention,
The non-image area was sufficiently hydrophilized, and no deposits such as printing ink were observed.

In Comparative Example C, the hydrophilicity was insufficient, and in Comparative Example D, the water retention of the raw plate was sufficient.
Since the copied image has deteriorated, only insufficient printed matter has been obtained from the start of printing due to the influence of the copied image.

Example 13 4.0 g of the binder resin (GP-11) of the present invention having the following structure, 6.0 g of the resin (B-7) having the following structure, and 30 g of the resin (B-8) 30 having the following structure
g, 200 g of photoconductive zinc oxide, 0.018 g of a cyanine dye [B] having the following structure and 300 g of toluene were dispersed in a ball mill for 3 hours to prepare a photosensitive layer-formed product, which was then subjected to conductive treatment on paper. Paint with a wire bar so that the dry adhesion amount becomes 20 g / m ² , dry at 100 ° C for 3 minutes, and then dry in a dark place.
An electrophotographic photosensitive material was produced by leaving the device at 0 ° C. and 65% RH for 24 hours.

The photosensitive material of the present invention was evaluated for electrostatic characteristics and image-capturability by the same operation as in Example 12. The results are shown below (30
° C, 80% RH).

V ₁₀ : −590V DRR: 85% E _1/10 : 25erg / cm ² E _1/100 : 40erg / cm ² Imaging: ◎: Very good The original plate made is 1 at a distance of 10 cm under irradiation of 300 W high pressure mercury lamp. After allowing to stand for a minute, ELP-EX was twice diluted with distilled water to pass through an etching machine once to obtain a printing original plate, which was printed in the same manner as in Example 1. 6000 prints of clear image quality without fog were printed.

Examples 14 to 19 Example 12 except that 3 g of each resin shown in Table 6 below was used in place of 3 g of the binder resin (GP-6) of the present invention.
Each photosensitive material was produced in the same manner as described above.

As shown in Table 6, not only at room temperature and normal humidity (20 ° C., 65% RH) but also at high temperature and high humidity (30 ° C., 80% RH), excellent electrostatic characteristics were obtained in the present invention. In addition, both the imaging performance and the water retention were good, and when printing was performed using the offset master plate, 6,000 or more printed materials with clear image quality without background contamination were obtained.

Example 20 6 g of the resin of the present invention (GP-12) having the following structure, 34 g of a binder resin (B-9) having the following structure, 200 g of photoconductive zinc oxide, 0.03 g of uranine, 0.075 g of rose bengal, and 0.045 g of bromophenol blue g, phthalanol anhydride 0.1 g and toluene 240 g were dispersed in a ball mill for 4 hours. This was applied to a conductive treated paper with a wire bar so as to have a dry adhesion amount of 20 g / m ² and heated at 100 ° C. for 3 minutes. Then 20 ℃, 65% RH
Was left for 24 hours under the above conditions to produce an electrophotographic photosensitive material.

w5.8 × 10 ^{4 The} obtained light-sensitive material was examined in the same manner as in Example 1 for its electrostatic properties and imaging properties. As a result, good results were obtained for the electrostatic characteristics as follows (30 ° C., 80% RH).

V ₁₀ = -550V DRR = 90% E _1/10 (lux-sec): 11.3, E _1/100 (lux-sec): 40 Also, the actual copied image is either normal temperature and normal humidity or high temperature and high humidity. Even under such a severe condition, a clear image with no background fog or fine line skipping was provided.

Further, the plate thus prepared was immersed in a 0.5 mol aqueous solution of monoethanolamine in 60% methyl ethyl ketone for 1 minute, and further passed through an etching machine once using an aqueous solution diluted twice with ELP-EX distilled water. After the desensitization treatment, in the same manner as in Example 1, up to 6000 printed materials at a printed place were obtained with clear image quality without background contamination.

(Effects of the Invention) According to the present invention, an electrophotographic lithographic printing plate precursor has excellent electrostatic characteristics (particularly dark charge retention and photosensitivity), reproduces a copied image faithful to the original image, and has an overall printed surface. It is possible to obtain a lithographic printing original plate which does not generate uniform background stains and of course dot background background stains and has excellent printing durability.

Further, it is possible to obtain an electrophotographic lithographic printing plate precursor that is effective for a scanning exposure method using a semiconductor laser beam.

Claims (1)

(57) [Claims] 1. A lithographic printing original plate utilizing an electrophotographic photoreceptor comprising a photoconductive layer comprising at least one layer of photoconductive zinc oxide and a binder resin on a conductive support. In, the binder resin contains a functional group which has at least one of a fluorine atom and a silicon atom and produces at least one group of a sulfo group, a phosphono group, a carboxyl group and a hydroxyl group by decomposition. one and a functional monomer, at least one and -COOH groups of the polymer component represented by the following general formula (II a) and _{(II b), -PO 3 H} 2 group, -SO ₃ H group , -OH group, At least one component containing at least one polar group selected from a group wherein R represents a hydrocarbon group or an -OR 'group (R' represents a hydrocarbon group), a -CHO group and a cyclic acid anhydride-containing group. Weight average molecular weight 2 in which a polymerizable double bond group represented by the following general formula (I) is bonded to only one end of a polymer main chain containing at least one kind of contained polymer component
An electrophotographic lithographic printing plate precursor comprising at least one graft-type copolymer comprising at least 10 ⁴ or less monofunctional macromonomer. General formula (I) In the formula (I), X ₀ represents —COO—, —OCO—, —CH ₂ OCO—, —CH
_{2 COO -, - O -,} - SO 2 -, - CO -, - CONHCOO -, - CO
NHCONH-, (Wherein Z ₁ represents a hydrogen atom or a hydrocarbon group). a _1, a _2, which may be the same or different, each represents a hydrogen atom, a halogen atom, a cyano group, a hydrocarbon group, -COOZ ₂ (Z ₂ through -COOZ ₂ or hydrocarbon is a hydrocarbon group )
Represents General formula (IIa) General formula (IIb) Wherein (II a) or (II b), X ₁ represents the same content as X ₀ in formula (I). Q ₁ represents an aliphatic group having 1 to 18 carbon atoms or an aromatic group having 6 to 12 carbon atoms. b ₁ and b ₂ may be the same or different, and represent the same contents as a ₁ and a ₂ in the formula (I). Q ₀ is -CN, -CONH ₂ or And 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).