JP2623166B2 - Lithographic printing plate - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an electrophotographic lithographic printing original plate made by an electrophotographic method, and in particular, to a surface having specific properties on a photoconductive layer. The present invention relates to a lithographic printing original plate provided with a layer.

(Prior art and its problems) At present, various types of offset masters for direct plate making have been proposed and put into practical use. Among them, photoconductive particles such as zinc oxide and a binder resin are particularly preferred on a conductive support. A photoreceptor provided with a photoconductive layer containing as a main component a normal electrophotographic process to form a toner image having high lipophilicity on the surface of the photoreceptor, and then the surface is made of a desensitizing solution called an etch solution. A technique for obtaining an offset original plate by selectively hydrophilizing a non-image portion by treating the non-image portion is widely used.

In order to obtain good printed matter, first, the original image is faithfully copied onto the offset original plate, and the surface of the photoreceptor is easily compatible with the desensitizing solution. In addition, in printing, the photoconductive layer having an image is not detached, and has good affinity with a fountain solution. Must be maintained.

In particular, as an offset master, the occurrence of background fouling due to insufficient desensitization is a major problem, and in order to improve this, various studies have been made on the development of a zinc oxide binding resin that improves desensitization. For example, Japanese Patent Publication No. 50-31011
No., JP-A-53-54027, JP-A-54-20735, JP-A-57
-202544 and JP-A-58-68046. However, even if these resins are said to be effective in improving the desensitization property, they are still unsatisfactory in background stain and printing durability when actually evaluated.

On the other hand, an electrophotographic member provided on an aluminum substrate having a photoconductive layer grained with an organic photoconductive compound as a photoconductive particle and a binder resin together with a binder resin can also be used.

In order to make a plate of this type, a non-image portion is dissolved and removed with a processing liquid after forming a toner image on the photosensitive layer by a usual electrophotographic method in the same manner as described above. As a result, the non-image portion becomes an aluminum substrate and becomes hydrophilic. For example, JP-B-37-17162, JP-B-46-39405
JP-B-52-2437, JP-A-56-107246, etc., using a photosensitive layer in which an oxadiazole compound or an oxazole compound is bound with an alkali-soluble resin such as a styrene-maleic anhydride copolymer. If or
JP-A-55-105254, JP-A-55-16125, JP-A-58-1
It is known to use a photosensitive layer composed of a phthalocyanine-based pigment or azo pigment and an alkali-soluble phenol resin, as described in JP-A-50953 and JP-A-58-162961, and the like.

However, in this plate-making process, a large-scale apparatus is required because the photosensitive layer in the non-image area must be dissolved and removed, and the plate-making speed becomes slow due to the time required. Furthermore, since ethylene glycol, glycerin, methanol, ethanol and the like are used as the processing liquid (organic solvent), this plate making method requires cost, safety, pollution,
Problems remain in occupational health.

Further, Japanese Patent Publication No. 45-5606 discloses a method for preparing a printing plate of a non-image area surface hydrophilic treatment type which is easy to make a plate by providing a specific resin layer on a usual electrophotographic photosensitive member. That is, a printing plate is disclosed in which a surface layer comprising a vinyl ether-maleic anhydride copolymer and a hydrophobic resin compatible therewith is provided on an electrophotographic photosensitive layer. This layer is a layer (hydrophilizable layer) that can be made hydrophilic by hydrolyzing the acid anhydride ring portion by treating the non-image portion with an alkali after forming the toner image.

The vinyl ether-maleic anhydride copolymer used therein becomes water-soluble when the ring is opened and hydrophilized, so that a layer is formed even if it is compatible with other hydrophobic resins. Even so, the water resistance was extremely poor, and the printing durability was at most 500 to 600 sheets.

Further, JP-A-60-90343, JP-A-60-159756, JP-A-61-217292 and the like disclose a surface layer containing a silylated polyvinyl alcohol as a main component and a crosslinking agent in combination. A method for providing a hydrophilic layer) is shown. That is, this layer hydrolyzes the silylated polyvinyl alcohol in the non-image area after forming the toner image to make it hydrophilic. Further, in order to maintain the film strength after hydrophilicity, the degree of silylation of polyvinyl alcohol is adjusted, and the remaining hydroxyl groups are crosslinked using a crosslinking agent.

It is described that the background stain property of the printed matter is improved and the number of printings is improved. However, when actually evaluated, it is still unsatisfactory, especially in the case of soiling. Further, silylated polyvinyl alcohol is produced by silylating polyvinyl alcohol to a desired ratio with a silylating agent, but since it is a polymer reaction,
It is difficult to manufacture stably. Further, since the chemical structure of the hydrophilized polymer is limited, 1) chargeability, 2) copy image quality (halftone dot reproducibility / resolution of image area, There is a problem that it is difficult to prevent the surface layer from affecting the exposure sensitivity and the like.

Further, the use of a resin containing a functional group that generates a hydrophilic group by decomposition as a surface layer resin is being studied. For example, a resin containing a functional group that generates a hydroxyl group by decomposition (Japanese Patent Application Laid-Open No. No. 272551, JP-A 1-2724
No. 89) and those containing a functional group which generates a carboxyl group upon decomposition (Japanese Patent Application Laid-Open No. 1-070769, Japanese Patent Application Laid-Open No. 63-197964)
No.) is disclosed.

These resins are resins that are hydrolyzed or hydrolyzed by a desensitizing solution or a fountain solution used for printing to generate a hydrophilic group.When these are used as a surface layer resin of a lithographic printing original plate, The hydrophilicity of the non-image part is improved by the generated hydrophilic group, the lipophilicity of the image part and the hydrophilicity of the non-image part become clear, and the printing ink is prevented from adhering to the non-image part during printing. It is described that as a result, it is possible to print a large number of prints of clear image quality without background contamination.

However, even if these resins are used, the background smear and the printing durability are still unsatisfactory. Even when a resin containing a hydrophilic group-forming functional group as described above is used, the hydrophilicity in the non-image area is further increased. When the content is increased in order to improve the content, the hydrophilicity generated by the decomposition increases the hydrophilicity and the surface layer resin becomes water-soluble. I understood.

Further, in order to solve the above problems, those containing a functional group that generates a hydroxyl group by decomposition as a surface layer resin, and those containing a functional group that generates a carboxyl group by decomposition, respectively, It contains a heat / photocurable functional group and has been crosslinked in advance (Japanese Patent Laid-Open No. 1-2549)
Nos. 70 and 1-283572), a heat / photocurable resin used in combination (Japanese Patent Application Laid-Open Nos. 1-262556 and 1-284860), and a crosslinking agent used in combination (Japanese Patent Application Laid-Open Nos. 1-263659 and 1-263659). 1-262861)
A combination of such functions is disclosed.

The combination of a heat / photo-curable functional group, a cross-linking agent, and the like in these resins can prevent the elution of the hydrophilic group-containing resin and improve the continuity of the hydrophilicity, but it has not been satisfactory yet.

Therefore, the effect by the hydrophilicity of the non-image portion is further improved,
The emergence of a technology that further improves sustainability is desired.

Further, in the conventional technique, there is a problem that the allowable range of the composition of the material when the overall balance of the electrophotographic properties, the film properties and the like is narrowed.

The present invention is to improve the problems of the electrophotographic lithographic printing plate precursor as described above.

SUMMARY OF THE INVENTION An object of the present invention is to provide a lithographic printing method that reproduces a faithful copy image with respect to an original image and does not generate not only a uniform background stain but also a dot-like background stain as an offset original plate, and has excellent desensitizing properties. To provide a master version.

Another object of the present invention is to provide a lithographic printing plate precursor having high printing durability, in which the hydrophilicity of the non-image portion is sufficiently maintained even when the number of printed sheets is increased in printing, and the background is not stained. .

Another object of the present invention is to provide a lithographic printing plate precursor having a resin used for a surface layer, which is a resin which can be hydrophilized in a non-image portion, and which is easily manufactured.

Another object of the present invention is to provide a lithographic printing plate precursor having a wide allowable range of the material composition in obtaining an overall balance of electrophotographic characteristics, skin properties, and the like.

(Means for Solving the Problems) The above objects are to provide a lithographic printing method using an electrophotographic photoreceptor having at least one photoconductive layer provided on a conductive support, and further having a surface layer provided on the uppermost layer. In the master plate, at least one of a sulfo group, a phosphono group, a carboxyl group, and a hydroxyl group is generated by decomposition containing at least one of a fluorine atom and a silicon atom as a main component of the surface layer. A functional group-containing monofunctional monomer and at least one of a polymer main chain containing at least one of the polymer components represented by the following general formulas (IIa) and (IIb): Weight average molecular weight 2 × formed by bonding a polymerizable double bond group represented by the following general formula (I)
10 ⁴ was found to be solved by a lithographic printing plate precursor, which comprises at least one at least comprising graft copolymer from the following monofunctional macromonomer.

General formula (I) In the formula (I), X ₁ represents —COO—, —OCO—, CH _{2 n} OCO
_{-, CH 2 m COO -,} - O -, - SO 2 -, - CO-, -CONHCOO-, -CONHCONH- or (D ₁ represents a hydrogen atom or a hydrocarbon group; n,
m represents an integer of 1 to 4).

a ₁ and a ₂ may be the same or different from each other, and represent a hydrogen atom,
A cyano group, a hydrocarbon group, a -COO-Z ₁ or -COO-Z ₁ via a hydrocarbon (Z ₁ represents a hydrogen atom or an optionally substituted hydrocarbon group).

General formula (IIa) General formula (IIb) Formula (II a) or (II b) in, X ₂ represents a X ₁ same contents as in formula (I). R 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).

R ₂ is -CH, -CONH ₂ or Wherein Y represents a hydrogen atom, a halogen atom, an alkoxy group or —COOZ ₂ (Z ₂ represents an alkyl group, an aralkyl group or an aryl group).

The present invention provides at least one hydrophilic group (sulfo group, phosphono group, carboxyl group) containing at least a fluorine atom and / or a silicon atom as a resin used for the surface layer of a lithographic printing plate precursor. ,
And / or a hydroxyl group) is characterized by containing a graft copolymer comprising at least a monofunctional monomer having at least one functional group and a monofunctional macromonomer. As a result, the lithographic printing plate precursor according to the present invention reproduces a copy image faithful to the original image, and has good hydrophilicity of the non-image portion, so that no background smearing occurs, and furthermore, the non-image portion has a long lasting hydrophilicity. There is an advantage that the printing durability is excellent due to the improvement.

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.

As the lithographic printing plate precursor, it is important that the surface portion of the non-image portion is sufficiently hydrophilized, whereas a known resin of a type that generates a hydrophilic group by the decomposition reaction is
It is uniformly dispersed throughout the surface layer. Therefore,
In order to sufficiently hydrophilize the surface of the known resin, a printable hydrophilic state is obtained only when a hydrophilic group-forming functional group is present in the entire surface layer and in a large proportion. On the other hand, in such a state, water is absorbed by the surface layer being hydrophilized, but the film is liable to be abnormally swollen or damaged due to the water absorption. As a result, the performance as a printing original plate is reduced (defects such as background smearing of a non-image portion and missing of an image portion are generated in a printed matter).

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 protecting group containing a fluorine atom and / or a silicon atom and decomposes to form a hydrophilic group. : A polymer component corresponding to a monofunctional macromonomer: segment A, and a graft copolymer comprising a segment B. The resin of the present invention has a specific behavior in the surface layer, unlike the conventionally known random copolymer. That is, it is presumed that a microphase-separated structure is formed due to the difference in compatibility between the segment A and the segment B. Further, there are many segments A which generate a hydrophilic group later on the surface portion of the surface layer. Therefore, it is considered that the effect of improving the hydrophilicity of the non-image portion is further enhanced, and the effect of preventing background stain during printing appears.

Furthermore, in the resin of the present invention in which a hydrophilic group is generated by the desensitizing treatment, the hydrophilic segment A portion faces the surface side, while the lipophilic segment B portion faces the opposite side of the surface, and By forming a microphase by the interaction of the segments B and exerting an anchor effect, the elution of the resin into an etchant and / or a fountain solution at the time of printing is suppressed. It was possible to maintain good hydrophilicity of the printed portions, and it was possible to obtain a large number of printed matter having good image quality.

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 graft copolymer containing a hydrophilic group-forming functional group is a resin containing at least one functional group represented by the general formula (IV).

-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.

The general formula (IV) -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 0 or the integer 2 and m ₂ represents an integer of 1-8) 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 ) ₂ C _m2 H _{2m2 + 1} group or It represents a group, the content of which represents the same content as content to be corresponding, respectively, in R ₁₁ described above.

L ₁ In the case of V ₁ represents an organic residue forming a cyclic imide group, containing a substituent containing a fluorine atom and a silicon atom. Specifically, as the cyclic imide ring residue to be formed,
Examples include a maleic imide group, a glutaconimide group, a succinimide group, and a phthalic imide group. As the substituent containing a fluorine atom and / or silicon atoms, and the hydrocarbon group represented by P _8, and -S-P ₉ group (P ₉ represents the same content as P ₈₎ or the like .

One of the preferred embodiments of the present invention includes a hydroxyl group-forming functional group, and specifically includes the following general formulas (V) to (V).
(VII).

In the general formula (V) -O-L ₂ formula (V), L ₂ is Represents P ₃ , P ₄ , and P ₅ represent the same symbols as described above.

General formula (VI) In the formula (VI), R ₃ and R ₄ may be the same or different from each other and represent a hydrogen atom or a group having the same contents 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 (VII) In the formula (VII), V ₂ , R ₃ and R ₄ are as defined above.

Specific examples of the functional groups represented by formulas (IV) to (VII) 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 As described above, the copolymer components containing the functional groups of the general formulas (IV) to (VII) used in the method for producing a desired resin by a polymerization reaction will be more specifically described.
For example, components represented by the following general formula (VIII) can be mentioned. However, it is not limited to these copolymer components.

General formula (VIII) In the formula (VIII), X ′ represents —O—, —CO—, —COO—,
−OCO−, −SO ₂ −, _{-CH 2 COO -, - CH 2} OCO-, Represents an aromatic group or a heterocyclic group (provided that e ₁ , e ₂ , e ₃ ,
e ₄ represents a hydrogen atom, a hydrocarbon group, or Y′-W in formula (VIII), and f ₁ and f ₂ may be the same or different, and each represents a hydrogen atom, a hydrocarbon group, or a formula Y'-W] in (VIII), and 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 has the formula (IV) ~ Represents a functional group represented by (VII).

c ₁ and c ₂ may be the same or different and include a hydrogen atom, a halogen atom (eg, a chlorine atom, a bromine atom, etc.), a cyano group, a hydrocarbon group (eg, a methyl group, an ethyl group, a propyl group, a butyl group, A methoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group, a butoxycarbonyl group, a hexyloxycarbonyl group, a methoxycarbonylmethyl group, an ethoxycarbonylmethyl group, a butoxycarbonylmethyl group, which may have 1 to 20 carbon atoms which may be substituted.
Alkyl, benzyl, aralkyl such as phenethyl, aryl such as phenyl, tolyl, silyl, chlorophenyl, etc.) or a substituent containing a -W group in formula (VIII). Which may represent an alkyl group, an alkenyl group, an aralkyl group, an alicyclic group, or an aromatic group having 1 to 18 carbon atoms.

Further, the [-X'-Y'-] bonding residue in the formula (VIII) is You may connect a part and -W directly.

W represents the symbolic content represented by the general formulas (IV) to (VII).

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)
It has a weight average molecular weight of 2 × 10 ⁴ or less which is bonded to only one end of a polymer main chain containing at least one of the polymer components represented by b).

In the general formula (I) of the macromonomer (M), X ₁ represents —COO—, —OCO—, CH _{2 n} COO—, CH _{2 m} C
OO -, - O -, - SO 2 -, Represents

 Here, n and m each represent an integer of 1 to 4.

d ₁ is a hydrogen atom, as a preferred hydrocarbon group,
An alkyl group having 1 to 18 carbon atoms which may be substituted (for example,
Methyl, ethyl, propyl, butyl, heptyl, hexyl, octyl, decyl, dodecyl,
Hexadecyl group, octadecyl group, 2-chloroethyl group, 2-bromoethyl group, 2-cyanoethyl group, 2-methoxycarbonylethyl group, 2-methoxyethyl group, 3
-Bromopropyl group and the like, and an optionally substituted alkenyl group having 4 to 18 carbon atoms (eg, 2-methyl-1-propenyl group, 2-butenyl group, 2-pentenyl group, 3-methyl-2-pentenyl group) , A 1-pentenyl group, a 1-hexenyl group, a 2-hexenyl group, a 4-methyl-2-hexenyl group and the like) an aralkyl group having 7 to 12 carbon atoms which may be substituted (for example, benzyl group, phenethyl group, 3 -Phenylpropyl group, naphthylmethyl group, 2-naphthylethyl group,
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, cyclohexyl) Group, 2-cyclohexylethyl group, 2-cyclopentylethyl group, etc.) or 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, dodecylphenyl group, methoxyphenyl group, ethoxyphenyl group, butoxyphenyl group, decyloxyphenyl group, chlorophenyl group, dichlorophenyl group, bromophenyl group, cyanophenyl group, acetylphenyl group, methoxy Carbonylphenyl group, ethoxycarbonyl Phenyl group, butoxycarbonylphenyl group, acetamidophenyl group, propionitrile amido phenyl group, such as dodecane white ylamide phenyl group).

X ₁ In the case where is represented, the benzene ring may have a substituent.
Examples of the substituent include a halogen atom (eg, a chlorine atom, a bromine atom, etc.), an alkyl group (eg, a methyl group, an ethyl group,
A propyl group, a butyl group, a chloromethyl group, a methoxymethyl group and the like; an alkoxy group (for example, a methoxy group, an ethoxy group, 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 (eg, a chlorine atom or a bromine atom), a cyano group, an alkyl group having 1 to 4 carbon atoms (eg, a methyl group, An ethyl group, a propyl group, a butyl group or the like), -COO-Z ₁ or COOZ ₁ via a hydrocarbon (Z ₁ is a hydrogen atom or an alkyl group having 1 to 18 carbon atoms, an alkenyl group,
Represents an aralkyl group, an alicyclic group or an aryl group, which may be substituted, specifically, represent represent) the same contents as those described above d _1.

Examples of the hydrocarbon in the —COO—Z ₁ group via the above hydrocarbon include a methylene group, an ethylene group, and a propylene group.

More preferably, in the general formula (I), X ₁ is -COO
-, - OCO -, - CH 2 OCO -, - CH 2 COO -, - O -, - CON
H, -SO ₂ NH- or Represents a ₁ and a ₂ may be the same or different from each other, and represent a hydrogen atom, a methyl group, -COO-Z ₁ or -CH ₂ COOZ ₁ (Z ₁ is
A hydrogen atom or an alkyl group having 1 to 6 carbon atoms (eg, a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, etc.)
Represents). Even more preferably, one of a ₁ and a ₂ always 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 (II a), X ₂ represents X ₁ same contents as in formula (I). 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).

R 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, phenethyl, 3-phenylpropyl, naphthylmethyl, 2-naphthylethyl,
Aliphatic groups such as chlorobenzyl group, bromobenzyl group, dichlorobenzyl group, methylbenzyl group, chloro-methyl-benzyl group, dimethylbenzyl group, trimethylbenzyl group, and methoxybenzyl group.

Further, an optionally substituted aryl group having 6 to 12 carbon atoms (eg, phenyl, tolyl, xylyl, chlorophenyl, bromophenyl, dichlorophenyl, chloro-methyl-phenyl, methoxyphenyl, methoxycarbonylphenyl) , A naphthyl group, a chloronaphthyl group, etc.). In the formula (IIa), X ₂ is preferably —COO—, —OCO—, CH ₂ COO—, —CH ₂ OCO
-, - O -, - CO -, - 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 formula (IIb), R ₂ represents —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, etc.) or -COOR '(R' 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) may contain two or more polymer components represented by the formula (II).

When R ₁ is an aliphatic group in the formula (IIa), it has 6 carbon atoms.
It is preferable to use the aliphatic groups of 12 to 12 in a range not exceeding 20% by weight of the total polymer components in the macromonomer (M).

Further, when X ₂ in the general formula (IIa) is —COO—, in all the 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), acrylonitrile, methacrylonitrile, acrylamides, etc. may be used as the monomer corresponding to the repeating unit copolymerizable with the polymer component represented by the formula (IIa) and / or (IIb). Methacrylamides, styrene and derivatives thereof (eg, vinyl toluene, chlorostyrene, dichlorostyrene, bromostyrene, hydroxymethylstyrene, N, N-dimethylaminomethylstyrene, etc.), and heterocyclic vinyls (eg, vinylpyridine, vinylimidazole, vinyl) Pyrrolidone, vinyl thiophene, vinyl pyrazole, vinyl dioxane, vinyl oxazine, etc.).

The macromonomer used in the present invention is, as described above, a compound represented by the general formula (I) only at one end of a polymer main chain comprising a repeating unit represented by the general formula (IIa) and / or (IIb). The polymerizable double bond group represented by is directly bonded or has a compound structure bonded by an arbitrary linking group. Formula (I) component and formula (IIa) or (II
b) The group connecting the components includes a carbon-carbon bond (single bond or double bond), a carbon-hetero atom bond (for example, an oxygen atom, a sulfur atom, a nitrogen atom, a silicon atom, etc.) It is composed of any combination of atomic groups of atom-heteroatom bonds.

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

Formula (IIIa) Formula (IIIb) In the formulas (IIIa) and (IIIb), a ₁ , a ₂ , b ₁ , b ₂ , X ₁ ,
X ₂ , R ₁ and R ₂ are each represented by the formulas (I), (IIa) and (II
Represents the same content as described in b).

Y ₁ is a mere bond or [D ₂ and d ₃ represent a hydrogen atom, a halogen atom (eg, a fluorine atom, a chlorine atom, a bromine atom, etc.), a cyano group, a hydroxyl group, an alkyl group (eg, a methyl group, an ethyl group, a propyl group, etc.)] , CH = CH, -O-, -S-, -COO -, - SO ₂ -, -NHCOO-, -NHCONH-, [D ₄ represents a hydrogen atom or a hydrocarbon group having the same content as R ₁ in the formula (IIa)] or a single linking group selected from an atomic group or an arbitrary combination thereof. Represents a linking group.

When the weight average molecular weight of the macromonomer (M) exceeds 2 × 10 ⁴ , the copolymerizability with the monomer represented by the monofunctional monomer of the present invention decreases. On the other hand, if the molecular weight is too small, the effect of improving the electrophotographic properties of the photosensitive layer becomes small.
It is preferably at least × 10 ³ .

The macromonomer (M) of the present invention can be produced by a conventionally known synthesis method. For example, a method by an ionic polymerization method in which various reagents are reacted with a terminal of a living polymer obtained by anionic polymerization or cationic polymerization to form a macromer, a carboxyl group in a molecule,
Using a polymerization initiator and / or a chain transfer agent containing a reactive group such as a hydroxy group or an amino group, an oligomer having a terminal reactive group bond obtained by radical polymerization is reacted with various reagents to form a macromer. And the like, and a method by a polyaddition condensation method in which a polymerizable double bond group is introduced into an oligomer obtained by a polyaddition or polycondensation reaction in the same manner as the above-mentioned radical polymerization method.

Specifically, P.Dreyfuss & R.P.Quirk, Encycl, Polym.S
ci.Eng., 7 , 551 (1987), PFRempp, E.Franta, Adu., Po
lym.Sci., 58 , 1 (1984), V.Percec, Appl., Polym.Sci., 2
85 , 95 (1984), R. Asami, M. TakaRi, Makvamol. Chem. Supp
l. 12 , 163 (1985), P, Rempp. et al, Makvamol. Chem. Supp
l. 8 , 3 (1984), Yusuke Kawakami, Chemical Industry, 38 , 56 (198
7), Yuya Yamashita, Polymer, 31 , 988 (1982), Shiro Kobayashi,
Polymer, 30, 625 (1981), Higashimura Satoshinobe, Journal of the Adhesion Society of Japan 1
8, 536 (1982), Koichi Ito, polymer processing, 35, 262 (198
6), can be synthesized according to the method described in the reviews such as Kishiro Higashi, Takashi Tsuda, Functional Materials, 1987 No. 10,5, and references and patents cited therein.

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.

Also a ₁ in each of the following examples represents -H or -CH _3, b ₁ represents -H, a -CH ₃ or -CH ₂ COOCH _3, b ₂ is -
Represents H or -CH _3, R ₁ is _{-C n H 2n + 1 (n} = 1~18 _{integer), - CH 2 C 6 H} 5, -C 6 H 5 or Are shown, R ₂ is _{-C n H 2n + 1, -} (CH 2) m C 6 H 5 (m = 1~3
Integer) or (Y ₁ is -CH _3, -Cl, -Br, shows a -OCH ₃₎ indicates, R ₃
Is -C _n H _{2n +} 1, shows a -CH ₂ C ₆ H ₅ or -C ₆ H _5, R ₄ is -C _n
H _{2n + 1} or indicates _{-CH 2 C 6 H 5, R} 5 is _{-C n H 2n + 1, -CH} 2 C 6
H ₅ or Y ₁ represents —Cl, —Br, —CH ₃ or —OCH ₃ );
₆ shows a _{-C n H 2n + 1, X} 1 is -COOCH _3, -C ₆ H ₅ or -CN
Are shown, X ₂ is _{-OC n H 2n + 1, -OCOC} q H 2q + 1 (q = 1~18 integer), - COOCH _3, shows a -C ₆ H ₅ or -CN, X ₃ is - CO
OCH _3, -C ₆ H _5, (Y ₂ are -Cl, shows -Br or -CH ₃₎ or indicates -CN, X ₄ represents -Cl, -Br, -F, and -OH, or -CN, X ₅
The _{-OCOC n H 2n + 1, -CN} , shows a -CONH ₂ or -C ₆ H _5, X
₆ represents -CN, a -CONH ₂ or -C ₆ H _5, X ₇ is -COOCH _3,
−C ₆ H ₅ or (Y ₁ is -Cl, -Br, showing a -CH ₃ or -OCH ₃₎ indicates, X ₈ is -H, -CH _3, -Cl, -Br, -OCH ₃ or -COO
CH ₃ is indicated, and P is an integer of 2 to 4.

Furthermore, the graft copolymer of the present invention contains, in addition to the above-mentioned monofunctional monomer containing a hydrophilic group-forming functional group and the above-mentioned monomer (M), other monomers other than these as a copolymerization component. May be.

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 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 photoconductive material is exemplified. 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 combination of a random copolymer of methacrylate and an acidic component-containing monomer having a weight average molecular weight of 20,000 or less and another resin having a weight average molecular weight of 30,000 or more or a compound curable 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 or heat having a weight average molecular weight of 30,000 or less And / or a resin composed of a combination with a compound curable by light (for example, JP-A-1-169455, JP-A-1-280761,
No. 1-214865, No. 2-874, Japanese Patent Application No. 63-221485,
Japanese Patent Application Nos. 63-220442 and 63-220441) may be used in combination.

When the graft-type copolymer of the present invention and the other resin described above are used in combination, the use ratio thereof can be used in any ratio, but preferably, the content of the graft resin is 0.5% in 100 parts by weight of all resins. % To 20% by weight, in particular 1 to 10% by weight.

In particular, when the resin of the present invention is used in combination with another resin (especially one that satisfies electrophotographic properties corresponding to semiconductor laser light), the resin of the present invention may be concentrated on the surface portion of the photoconductive layer. It was confirmed that only a very small amount was required.

As a result, while maintaining excellent electrophotographic properties,
The resin of the present invention, which has developed a hydrophilic group by desensitization treatment, is efficiently present on the surface portion of the surface layer, the hydrophilicity of the resin is effectively achieved, and the image quality and background stain of printed matter are significantly improved. It is now possible.

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 surface layer of the photoconductive layer,
It is presumed that the graft copolymer of the present invention can be concentrated and exist on the surface portion of the surface layer, despite the small amount of use as described above. 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, when the copolymer is used as a resin for a lithographic printing plate precursor as described above, the hydrophilicity of the non-image area to be hydrophilized by the desensitizing solution contains the hydrophilic group generated in the resin. Since the segment A portion is further enhanced by being concentrated on the surface portion of the surface layer, 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 significantly interacts with the zinc oxide and / or other resin in the photoconductive layer. Therefore, the segment B portion acts as an anchor and dissolves. Has the effect of preventing 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, excellent electrophotography using a resin exhibiting good electrophotographic properties even when environmental conditions fluctuate or showing good electrophotographic properties even in a scanning exposure system using a semiconductor laser beam as a light source. The effect of improving hydrophilicity is changed by using the graft copolymer of the present invention in a photoconductive layer exhibiting characteristics and having good reproducibility of the original image of a copied image in a usage amount that does not impair these performances 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.

In order to improve the strength of the surface layer itself that can be hydrophilized, the adhesion to the electrophotographic photosensitive layer or the electrophotographic properties, etc., a resin other than the above-described resin of the present invention is added, or a crosslinking agent or a plasticizer is used. It may be added.

As the crosslinking agent, commonly used organic peroxides, metal soaps, organic silanes, crosslinking agents such as polyurethane, and curing agents such as epoxy resins can be used. Specifically, "Handbook of Crosslinking Agents" edited by Tozo Yamashita and Tosuke Kaneko
It is described in Taiseisha (1981) and the like.

Further, the surface layer that can be made hydrophilic may have a surface that is mechanically matted for the purpose of improving development characteristics at the time of toner development, adhesiveness of a toner image or water retention after a hydrophilic treatment. May contain a matting agent. As a matting agent, silicon dioxide, zinc oxide, titanium oxide,
Examples include fillers such as zirconium oxide, glass particles, alumina, and clay, and polymer particles such as polymethyl methacrylate, polystyrene, and phenol resin.

What is important when constituting the surface layer is, as described above,
That is, the non-image portion changes sufficiently hydrophilicity after the desensitization treatment.

That is, the hydrophilicity can be confirmed, for example, by measuring a contact angle with water. The contact angle of water on the surface of the surface layer (hydrophilizable layer) before desensitizing treatment is about 60 ° to 120 °, but after desensitizing, it decreases to about 5 ° to 20 ° And get very wet with water. For this reason, the printing plate has an image portion made of lipophilic toner and a highly hydrophilic non-image portion formed on its surface. Therefore, the surface layer after the desensitization treatment may have a contact angle with water of 20 degrees or less.

The present invention is particularly excellent in that its hydrophilicity is further better than that of the conventional one.

For the electrophotographic photosensitive layer (photoconductive layer) used in the present invention, any photoconductive substance can be used irrespective of an inorganic photoconductive compound or an organic photoconductive compound.

Examples of the inorganic photoconductive substance include, for example, zinc oxide, titanium oxide, zinc sulfide, selenium, selenium alloy, cadmium sulfide, cadmium selenide, and silicon, which form a photoconductive layer together with a binder resin. Alternatively, the photoconductive layer may be formed alone by vapor deposition or sputtering. As the organic photoconductive substance, for example, in the case of a polymer, the following (1) to (5) can be exemplified.

(1) Polyvinylcarbazole and derivatives thereof described in JP-B-34-10966, (2) Polyvinylpyrene, polyvinylanthracene, poly-2-vinyl- described in JP-B-43-18874 and JP-B-43-19192 Vinyl polymers such as 4- (4'-dimethylaminophenyl) -5-phenyl-oxazole and poly-3-vinyl-N-ethylcarbazole; (3) polyacenaphthylene described in JP-B-43-19193; Polymers such as polyindene, a copolymer of acenaphthylene and styrene, and (4) condensation resins such as pyrene-formaldehyde resin, bromopyrene-formaldehyde resin, ethylcarbazole-formaldehyde resin described in JP-B-56-13940. (5) Various types of triphenylmethane poly described in JP-A-56-90833 and JP-A-56-161550 Over.

Examples of the low molecular weight compounds include the following (6) to (18).

(6) Triazole derivatives described in U.S. Pat. No. 3,112,197, etc., (7) Oxadiazole derivatives described in U.S. Pat. No. 3,189,447, etc., (8) JP-B-37-16096 And imidazole derivatives described in (9) U.S. Pat. Nos. 3615402, 3820989, and 354254
No. 4, JP-B-45-555, JP-B-51-10983, JP-A-51
-93224, JP-A-55-17105, JP-A-56-4148, JP-A-55-108667, JP-A-55-156953, JP-A-56-36
No. 656, polyarylalkane derivatives described in gazettes, etc .; (10) U.S. Pat. Nos. 3,180,729 and 4,278,746;
No.-88064, JP-A-55-88065, JP-A-49-105537,
JP-A-55-51086, JP-A-56-80051, JP-A-56-88
No. 141, JP-A-57-45545, JP-A-54-112637, JP-A-55-74546, pyrazoline derivatives and pyrazolone derivatives described in the gazettes, and the like. (11) U.S. Pat. Description, JP-B-51-10105
No., JP-A-54-83435, JP-A-54-110836, JP-A-5-108
4-119925, JP-B-46-3712, JP-B-47-28336, and phenylenediamine derivatives described in the gazettes, etc. (12) U.S. Patent No. 3,567,450, JP-B-49-35702, West Germany Patent (DAS) 1110518, U.S. Patent No. 3,180,703, U.S. Patent No. 3,240,597, U.S. Patent No. 3,658,520, U.S. Patent No. 42
No. 32103, U.S. Pat.No. 4,175,961, U.S. Pat.No. 4,012,376
No., JP-A-55-144250, JP-A-56-119132, Japanese Patent Publication No.
39-27577, JP-A-56-22437, publications and the like, (13) amino-substituted chalcone derivatives described in U.S. Pat. No. 3,352,501, (14) U.S. Pat. No. 3,542,546 N, N-bicarbazyl derivatives described in Japanese Patent No. 3257203, etc .; (16) styryl anthracene derivatives described in JP-A-56-46234 and the like; (17) fluorenone derivatives described in JP-A-54-110837 and the like; (18) U.S. Patent No. 3717462, JP-A-54-59143, JP-A-55-52063, and JP-A-55-52063 No. 52064, JP-A-55-46760
JP-A-55-85495, JP-A-57-11350, JP-A-57
Hydrazone derivatives disclosed in each specification, publication and the like.

These photoconductive substances may be used in combination of two or more in some cases.

Among these photoconductive materials are poly-N-vinylcarbazole; triarylamines such as tri-p-tolylamine and triphenylamine; 4,4'-bis (diethylamine) -2,2'-dimethyltriazole. Polyarylmethanes such as phenylmethane; and 3- (4-
Unsaturated heterocycle-containing compounds represented by pyrazoline derivatives such as (dimethylaminophenyl) -1,5-diphenyl-2-pyrazoline and the like are preferably used.

As binding agents that can be combined, all conventionally known binding agents can be used. Typical are vinyl chloride-vinyl acetate copolymer, styrene-butadiene copolymer, styrene-butyl methacrylate copolymer, polymethacrylate, polyacrylate, polyvinyl acetate, polyvinyl butyral, alkyd resin, silicone resin, epoxy resin , An epoxy ester resin, a polyester resin and the like. It is also possible to combine with an aqueous acrylic emulsion or acrylic ester emulsion.

For examples of certain polymeric materials useful as binders, see Research Disclos.
ure), Vol. 109, pp. 61-67 under the heading "Electrophotographic Elements, Materials and Methods".

Generally, the amount of binder present in the photoconductive composition used in the present invention can vary. Typically, useful amounts of binder are in the range of about 10 to about 90% by weight, based on the total mixture of photoconductive material and binder.

Further, a conventionally known compound can be added as a spectral sensitizer. Examples thereof include xanthene dyes, triphenylmethane dyes, azine dyes, phthalocyanine dyes (including metals), polymethine dyes, and the like. Specifically, Harumi Miyamoto, Hidehiko Takei, "Imaging" 1973 ( N
o.8), 2; CJ Young, RCA Review 15 469 (1954); Kohei Kiyota, IEICE Transactions J63-C (No. 2), 97 (198)
0); Yuji Harasaki et al., Industrial Chemistry Magazine, 66 , 78 and 188 (196
3); Tadaaki Tani, Journal of the Photographic Society of Japan, 35 , 208 (1972); Resea
rch Disclosure, 1982, 216 , 117-118; Comprehensive technical materials "Recent development and practical application of photoconductive materials and photoconductors" Published by Nihon Kagaku Informatics Co., Ltd. (1986) And the like.

The photoconductive layer may be formed of one layer, or may be formed of two or more layers.

In the case of a multilayer, for example, the inorganic photoconductor or a phthalocyanine pigment, a charge generation layer composed of an organic pigment such as an azo pigment and a binder resin added as necessary, and the above-described polymer compound or low-molecular compound And a so-called function-separated type photoconductive layer in which a charge transport layer made of a binder resin is laminated.

The photoconductive layer used in the present invention can be provided on a commonly used known support. Generally speaking, the support of the electrophotographic photosensitive layer is preferably conductive, and as the conductive support, as in the prior art, for example, metal,
Conductive treatment by impregnating a substrate such as paper or plastic sheet with a low-resistance substance, etc., imparting conductivity to the back surface of the substrate (opposite to the surface on which the photosensitive layer is provided), and further prevent curling, etc. One coated with at least one layer for the purpose of, one provided with a water-resistant adhesive layer on the surface of the support,
If necessary, at least one or more precoat layers may be provided on the surface layer of the support, or a substrate-based plastic obtained by evaporating Al or the like may be laminated on paper.

Specifically, as an example of a conductive substrate or a conductive material, Yukio Sakamoto, “Electrophotography” 14, (No. 1), pp. 2-11 (1975); Molecular Publishing Association (1975); MFHoover, J. Macromol. Sci. Chem., A-4.
(6), pages 1327 to 1417 (1970) and the like can be used.

The coating thickness of the photoconductive composition on a suitable support can vary widely. Usually, it can be applied in a range from about 10 microns to about 300 microns (but before drying). The preferred range of coating thickness before drying has been found to be in the range of about 50 microns to about 150 microns. However, useful results can be obtained outside of this range. The dried thickness of the coating may be in the range of about 1 micron to about 50 microns.

The thickness of the surface area that can be hydrophilized in the present invention is 10 μm or less, and particularly preferably 0.1 to 5 μm for the Carlson process.

If the thickness is more than 5 μm, there may be inconveniences such as a decrease in sensitivity of the lithographic printing plate precursor as an electrophotographic photosensitive member and an increase in residual potential.

To actually prepare the lithographic printing plate precursor of the present invention, generally, first, an electrophotographic photosensitive layer (photoconductive layer) is formed on a conductive support in accordance with a conventional method. Next, on this layer, the boiling point of the resin of the present invention and, if necessary, the above-mentioned additives and the like are added.
It can be produced by dissolving or dispersing in a volatile hydrocarbon solvent at a temperature of 200 ° C. or lower, coating and drying. As the organic solvent to be used, specifically, halogenated hydrocarbons having 1 to 3 carbon atoms such as dichloromethane, chloroform, 1,2-dichloroethane, tetrachloroethane, dichloropropane, and trichloroethane are preferable. Other solvents used in the coating composition, such as aromatic hydrocarbons such as chlorobenzene, toluene, xylene or benzene, ketones such as acetone or 2-butanone, ethers such as tetrahydrofuran, and methylene chloride; Can also be used.

From the original obtained as described above, a toner image is formed on the original according to a usual electrophotographic method. The printing plate can be obtained by treating this with a desensitizing solution (for example, an acidic or alkaline aqueous solution or an aqueous solution in which a reducing agent is dissolved) to change the non-image area to hydrophilic.

As described above, the use of the hydrophilic layer in the invention makes it possible to use any conventionally known electrophotographic photoreceptor as a high-quality lithographic printing original plate. The hydrophilizable layer is a film that achieves both high hydrophilicity and water resistance after the hydrophilic treatment, and also has extremely good adhesion to the toner image. It is extremely suppressed and has high printing durability.

Further, since the printing plate of the present invention can maintain almost the original sensitivity of the electrophotographic photosensitive layer as it is, a printing original plate having a remarkably high sensitivity can be obtained as compared with a conventional printing original plate for electrophotographic plate making. In addition, conventionally, only one material such as zinc oxide can be used because it must have the property that photoconductivity and hydrophilization can be performed in one layer. Since the function is separated into the hydrophilic layer, the selection range of the photoconductive layer is widened. Therefore, if a material having high sensitivity in a long wavelength light region is selected, for example, a He-Ne laser which has been impossible in the past can be obtained. And writing with a semiconductor laser.

Further, in the printing original plate of the present invention, the non-image portion becomes hydrophilic,
Since it can be made only by immersing in the hydrophilic treatment solution for a few seconds, plate making can be performed with a small and simple apparatus.

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

Production Example 1 of Macromonomer 1: A mixed solution of 95 g of MM-1 methyl methacrylate, 5 g of thioglycolic acid and 200 g of toluene was stirred under a nitrogen stream while stirring.
Heated to a temperature of 75 ° C. 1.0 g of 2,2'-azobisisobutyronitrile (abbreviation: AIBN) was added and reacted for 8 hours. Next, 8 g of glycidyl methacrylate and N, N-
1.0 g of dimethyldodecylamine and 0.5 g of t-butylhydroquinone were added, and the mixture was stirred at a temperature of 100 ° C. for 12 hours. After cooling, the reaction solution was reprecipitated in methanol 2 to obtain 82 g of a white powder. The weight average molecular weight (hereinafter, w) of the polymer is
It was 8.3 × 10 ³ .

Production Example 2 of Macromonomer: MM-2 A mixed solution of 95 g of methyl methacrylate, 5 g of thioglycolic acid, and 200 g of toluene was heated to 70 ° C. while stirring under a nitrogen stream. 1.5 g of AIBN was added and reacted for 8 hours. Next, glycidyl methacrylate 7.
5 g, N, N-dimethyldodecylamine 1.0 g and t-butylhydroquinone 0.8 g were added, and the mixture was stirred at a temperature of 100 ° C. for 12 hours. After cooling, the reaction solution was reprecipitated in methanol 2 to obtain 85 g of a colorless and transparent viscous substance. The w of the polymer is 4.5
× was 10 ^3.

Production Example 3 of Macromonomer: A mixed solution of 94 g of MM-3 butyl methacrylate, 6 g of 2-mercaptoethanol and 200 g of toluene was heated to a temperature of 70 ° C. under a nitrogen stream. 1.2 g of AIBN 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, reprecipitate in methanol 2 to give a colorless, transparent, viscous substance.
79 g were obtained. w was 6.3 × 10 ³ .

Production Example 4 of Macromonomer: MM-4 A mixed solution of 95 g of ethyl methacrylate and 200 g of toluene was heated to a temperature of 70 ° C. under a nitrogen stream. 5 g of 2,2'-azobis (cyanoheptanol) was added and reacted for 8 hours.

After cooling, the temperature of the reaction solution was adjusted to 20 ° C. in a water bath, 1.0 g of triethylamine and 21 g of methacrylic anhydride were added, and the mixture was stirred for 1 hour and then at 60 ° C. for 6 hours.

After cooling the obtained reaction product, it was reprecipitated in methanol 2 to obtain 75 g of a colorless and transparent viscous substance. w was 8.6 × 10 ³ .

Production Example 5 of Macromonomer: A mixture of 97 g of MM-5 propyl methacrylate, 3 g of 3-mercaptopropionic acid, and 200 g of toluene was heated at a temperature of 70 g under a nitrogen stream.
The solution was heated to ° C to obtain a homogeneous solution. Add 2.0 g of AIBN, 8
Reacted for hours. After cooling, the precipitate was reprecipitated in methanol 2 and heated to 50 ° C. under reduced pressure to distill off the solvent. The obtained viscous substance was dissolved in 200 g of toluene, and 16 g of glycidyl methacrylate, 1.0 g of N, N-dimethyldodecyl methacrylate and 1.0 g of t-butylhydroquinone were added to the mixed solution, and the mixture was stirred at a temperature of 110 ° C. for 10 hours. This reaction solution was reprecipitated in methanol 2 again. The w of the obtained pale yellow viscous substance was 6.5 × 10 ³ .

Production Example 6 of Macromonomer: MM-6 A mixed solution of 95 g of benzyl methacrylate, 5 g of thioglycolic acid and 200 g of toluene was heated to a temperature of 75 ° C. while stirring under a nitrogen stream. 1.5 g of AIBN was added and reacted for 8 hours. Next, the reaction solution was brought to a temperature of 25 ° C., and a mixed solution of 10 g of dicyclohexylcarbodiimide (abbreviated as DCC) to which 8 g of 2-hydroxyethyl methacrylate was added, 0.2 g of 4- (N, N-dimethylamino) pyridine and 50 g of methylene chloride was added. The mixture was added dropwise with stirring for 30 minutes. The reaction was further continued for 3 hours. Next, formic acid (5 ml) was added, and the mixture was stirred for 1 hour. Then, the insoluble material was suction-filtered using celite, and the obtained filtrate was reprecipitated in hexane (1.5). The precipitated viscous matter was collected by decantation and dissolved using 200 ml of tetrahydrofuran, and a small amount of insoluble matter was filtered by suction filtration using celite in the same manner as described above. The filtrate was reprecipitated in hexane 1 again, and the precipitated viscous matter was collected by decantation and dried under reduced pressure.

The w of the obtained colorless viscous substance was 4.5 × 10 ³ .

Production example 7 of macromonomer: MM-7 methyl methacrylate 40 g, ethyl acrylate 54 g,
A mixture of 6 g of 2-mercaptoethylamine, 150 g of toluene and 50 g of tetrahydrofuran was heated to a temperature of 75 ° C. while stirring under a nitrogen stream. 2.0 g of AIBN was added and reacted for 8 hours. Next, this reaction solution was brought to a temperature of 20 ° C. in a water bath, and 23 g of methacrylic anhydride was added dropwise thereto so as not to exceed a temperature of 25 ° C., followed by further stirring for 1 hour. 2,2'-
Methylenebis- (6-t-butyl-p-cresol) 0.
5 g was added, and the mixture was stirred at a temperature of 40 ° C for 3 hours. After cooling, this solution was reprecipitated in methanol 2 to obtain 83 g of a viscous substance.
w was 7.5 × 10 ³ .

Production Example 8 of Macromonomer: MM-8 A mixed solution of 95 g of methyl methacrylate, 150 g of toluene and 50 g of ethanol was heated to a temperature of 75 ° C. under a nitrogen stream. 5 g of ACV was added and reacted for 8 hours. Next, glycidyl acrylate 15 g, N, N-dimethyldodecylamine 1.0 g
And 1.0 g of 2,2'-methylenebis- (6-t-butyl-p-cresol), and the mixture was stirred at a temperature of 100 ° C for 15 hours. After cooling, the reaction solution was reprecipitated in methanol 2 to obtain 83 g of a transparent viscous substance. w was 5.3 × 10 ³ .

Macromonomer Production Examples 9 to 27: MM-9 to MM-27 In the Macromonomer Production Example 6, the same operation as in Production Example 2 was performed except that the monomers in Table 1 were used instead of propyl methacrylate. Thus, a macromonomer was produced.
The w of each macromonomer was 4 × 10 ^{3 to} 5.5 × 10 ³ .

Binder Resin Preparation Example 1: GP-1 A mixed solution of 70 g of the following compound (A-1), 30 g of macromonomer (MM-1) of Preparation Example 1 of macromonomer and 200 g of toluene was added 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 80 g of the following compound (A-2), 20 g of the macromonomer (MM-6) of Preparation Example 6 for 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 70 g of the following compound (A-3), Production Example 1 of macromonomer
A polymerization solution was prepared in the same manner as in Production Example 1 except that a mixed solution of 30 g of the macromonomer (MM-13) of Example 3 and 200 g of toluene was prepared. The w of the obtained polymer was 5.3 × 10 ⁴ .

Binder Resin Production Examples 4 to 10: GP-4 to GP-10 In Production Example 3, instead of 70 g of the compound (A-3) and 30 g of the macromonomer (MM-13), the respective compounds shown in Table 2 below were used. Except for using each, each polymer was produced in the same manner as in Production Example 3. W of each polymer is 4.5 × 10 ^{4 to} 6 × 10 ⁴
Met.

Example 1 5 g of 4,4'-bis (diethylamino) -2,2'-dimethyltriphenylmethane, 5 g of bisphenol A polycarbonate (manufactured by GE, trade name Lexan 121) as an organic photoconductive substance, the following structural formula Spectral sensitizing dye (A) 40m
g) As a chemical sensitizer, 0.2 g of an anilide compound (B) having the following structural formula was dissolved in a mixture of 30 ml of methylene chloride and 30 ml of ethylene chloride to obtain a photosensitive solution.

This photosensitive solution is applied on a conductive transparent support (a 100 μm polyethylene terephthalate support having a deposited film of indium oxide on a 100 μm polyethylene terephthalate support; a surface resistance of 10 ³ Ω) using a wire round rod to form a photosensitive layer of about 4 μm. Was obtained.

A 5% by weight toluene solution of a binder resin GP-1 and poly (methacrylate) in a (1/9) weight ratio was applied to the surface of the electrophotographic photoreceptor obtained above using a doctor blade, and the solution was applied to a surface of about 2 μm.
m of the surface layer was formed. 0.5% of this photosensitive material
A boric acid aqueous solution having a concentration was used as a desensitizing solution, and immersed in this solution for 5 minutes to perform desensitizing treatment.

A drop of 2 μm of distilled water was placed on this, and the contact angle with the formed water was measured by a goniometer and found to be 10 ° or less. The contact angle before the desensitizing treatment was 85 °, which clearly indicates that the surface layer of the photosensitive material was very well hydrophilized.

The original plate obtained in this way is fully automated plate making machine ELP404V (Fuji Photo Film Co., Ltd.) using a negatively charged liquid developer.
To form a toner image, desensitizing treatment under the same conditions as above, and using this as an offset master, it was printed on a high-quality paper using an offset printing machine (Oliver 52, manufactured by Sakurai Seisakusho Co., Ltd.). .

The number of sheets that can be printed without causing any problem in the background stain on the non-image portion and the image quality of the image portion of the printed matter was 5,000.

Example 2 5 g of a bisazo pigment having the following structural formula, 95 of tetrahydrofuran
g and polyvinyl butyral resin (manufactured by Denki Kagaku Kogyo Co., Ltd .:
A mixture of 30 g of a 5% by weight solution of denkabutyral # 4000-1) in tetrahydrofuran was sufficiently pulverized with a ball mill, and then the mixture was taken out and 520 g of tetrahydrofuran was added with stirring. This dispersion was coated on the conductive transparent support used in Example 1 using a wire round rod to form a charge generation layer of about 0.7 μm.

Next, a mixed solution of 20 g of a hydrazone compound having the following structural formula, 20 g of a polycarbonate resin (manufactured by GE, trade name: Lexan 121) and 160 g of tetrahydrofuran was applied on the charge generating layer using a wire round rod to a thickness of about 18 μm. An electrophotographic photoreceptor having a charge transport layer and having a two-layer photosensitive layer was obtained.

Binder resin GP-7, [methyl methacrylate / methyl acrylate (7/3) weight ratio] copolymer, silica gel
0/5] A dispersion obtained by dispersing 5% by weight of a toluene mixture in a weight ratio with ultrasonic waves for 5 minutes was applied on the photosensitive layer with a doctor blade to form a surface layer of about 2 μm.

The photosensitive material thus prepared was charged to -6 kV with a paper analyzer (SP-428, manufactured by Kawaguchi Electric), and the initial potential (V ₀ ), dark charge retention (DRR), and light attenuation exposure (E
_1/10 ), V ₀ = −500 V, DRR = 83%, and E _1/10 = 15.0 [1 ux · sec].

Further, this was similarly applied to the fully automatic plate making machine ELP404 in the same manner as in Example 1.
When a plate was prepared using ELP-T toner at V, the density of the obtained master plate for offset printing was 1.0 or more and the image quality was clear. Further, after etching and printing with a printing machine, the printed matter after printing 5,000 sheets had no fog in the non-image area and the image was clear.

Example 3 Binder resin GP-9, [weight ratio of methyl methacrylate / glycidyl methacrylate / acrylic acid (89/10/1)] copolymer, silica gel and phthalic anhydride [5/90/5 / 0.01]
A dispersion obtained by dispersing a 5% by weight toluene mixture in a weight ratio by ultrasonic waves for 10 minutes was applied to the surface of the electrophotographic photosensitive member obtained in Example 1 with a doctor blade, and the temperature was 80 ° C. for 30 minutes, and further 100 ° C. For 1 hour to form a surface layer having a thickness of about 2 μm.

The lithographic printing plate precursor thus produced was operated and printed under the same conditions as in Example 1. The number of printable sheets was 6000 or more without causing any problem in the background stain on the non-image portion and the image quality of the image portion of the printed matter.

Example 4 [Methyl methacrylate / ethyl methacrylate / acrylic acid (39/60/1 weight ratio)] 45 g of copolymer (weight average molecular weight 42000), zinc oxide 200 g, rose bengal 0.03 g,
0.02 g of tetrabromophenol blue, 0.1 of phthalic anhydride
A mixture of 5 g and 300 g of toluene was dispersed in a ball mill for 2 hours to prepare a photosensitive layer-formed product, which was coated on a conductive treated paper with a wire bar so that the dry adhesion amount was 25 g / m ^2, and 100 Dried at ℃ for 1 minute.

The surface layer dispersion used in Example 3 was applied to the upper layer of the above photoreceptor with a doctor blade, dried at a temperature of 100 ° C. for 30 seconds, and then heated at 110 ° C. for 2 hours to obtain a film thickness of about 2.1 μm. Was formed.

Then, it was left standing in a dark place at 20 ° C. and 65% RH for 24 hours to prepare an electrophotographic photosensitive material.

This photosensitive material was charged to -6 kV with a paper analyzer, and the initial potential (V ₀ ) was -520 V and the dark charge retention ratio (DRR) was 85.
% And a light attenuation exposure amount (E _1/10 ) of 13.0 [lux · sec].

Further, this was subjected to plate making in the same manner as in Example 2, and the density of the obtained master plate for offset printing was 1.0 or more, and the image quality was clear.

After etching and printing with a printing machine, 50
The printed matter after printing 00 sheets had no fog in the non-image area, and the image was clear.

Examples 5 to 10 In Example 4, the resin of the present invention [GP
-9], except that each resin described in Table 3 was used.
A photosensitive material was produced in the same manner as in Example 4.

When this was subjected to plate making using the same apparatus as in Example 1, the density of the obtained offset printing master plate was 1.0 or more, and the image quality was clear. Further, after printing by a printing machine after etching treatment, the printed matter after printing 5,000 sheets had clear image quality without fog.

Further, after the photographic material was allowed to stand at 45 ° C. and 75% RH, the same processing as described above was performed, but it was not different from that before aging.

(Effects of the Invention) As described above, the electrophotographic lithographic printing plate precursor having the surface layer having the hydrophilic layer containing the resin of the present invention has both high hydrophilicity and water resistance after the hydrophilic treatment. Since it is a film and has extremely good adhesion to a toner image, the resulting lithographic printing plate precursor has excellent quality in terms of both background contamination and printing durability.

 Furthermore, the resin of the present invention is easy to produce.

Claims (1)

(57) [Claims] 1. A lithographic printing plate precursor using an electrophotographic photosensitive member comprising at least one photoconductive layer provided on a conductive support and further having a surface layer provided on the uppermost layer thereof. Monofunctional containing a functional group containing at least one of a fluorine atom and a silicon atom and generating at least one of a sulfo group, a phosphono group, a carboxyl group and a hydroxyl group by decomposition as a component A monomer represented by the following general formula (I) only at one end of a polymer main chain containing at least one of the polymer components represented by the following general formulas (IIa) and (IIb): Weight average molecular weight 2 formed by bonding polymerizable double bond groups
A lithographic printing plate precursor comprising at least one graft-type copolymer comprising at least × 10 ⁴ monofunctional macromonomers. General formula (I) In the formula (I), X ₁ represents —COO—, —OCO—, CH _{2 n} OCO—,
_{CH 2 m COO -, - O} -, - SO 2 -, - CO-, -CONHCOO-, -CONHCONH- or (D ₁ represents a hydrogen atom or a hydrocarbon group; n,
m represents an integer of 1 to 4). a _1, a _2, which may be the same or different, a hydrogen atom, a cyano group, a hydrocarbon group, -COO-Z ₁ or -COO-Z ₁ via a hydrocarbon (Z ₁ are being hydrogen atom or a substituent Represents a good hydrocarbon group). General formula (IIa) General formula (IIb) Formula (II a) or (II b) in, X ₂ represents a X ₁ same contents as in formula (I). R 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). R ₂ is -CH, -CONH ₂ or Wherein Y represents a hydrogen atom, a halogen atom, an alkoxy group or —COOZ ₂ (Z ₂ represents an alkyl group, an aralkyl group or an aryl group).