JP2627012B2 - Photosensitive lithographic printing plate - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a negative-working photosensitive lithographic printing plate, and more particularly, it can be developed with an aqueous alkali developing solution, has good photocrosslinking properties, and has higher resistance to light. A photosensitive lithographic printing plate that has the printing power and does not stick the interleaf paper at a temperature higher than room temperature, and the plates do not stick together even after a long period of time under pressure. It is about.

[Conventional technology and problems to be solved]

The majority of those used as a photosensitive substance in pre-sensitized negative-working printing materials are diazonium compounds, the most commonly used of which is represented by a formaldehyde condensate of p-diazodiphenylamine. There is a diazo resin.

The composition of the photosensitive layer of a photosensitive lithographic printing plate using a diazo resin is, for example, as described in U.S. Pat.No. 2,714,066, a diazo resin alone, that is, without using a binder, for example, As described in JP-A-50-30604, it can be classified into those in which a binder and a diazo resin are mixed.In recent years, many photosensitive lithographic printing plates using a diazonium compound have been It is composed of a diazonium compound and a polymer as a binder to provide high printing durability.

As such a photosensitive layer, as described in JP-A-50-30604, a so-called alkali developing type in which unexposed portions are removed (developed) by an aqueous alkaline developing solution, and an organic solvent-based developing solution The so-called solvent development type, which is removed by the above method, is known, but from the viewpoint of occupational safety and health, the alkali development type has attracted attention. As a binder useful for such an alkali developing type photosensitive layer, a monomer containing a carboxylic acid such as 2-hydroxyethyl (meth) acrylate and methacrylic acid as described in JP-A-50-30604 is mentioned. And a carboxylic acid introduced into the polymer by reacting a hydroxyl group of polyvinyl alcohol with a cyclic anhydride such as phthalic anhydride as described in U.S. Pat.No. 2,861,058. However, the resulting polymer was poor in abrasion resistance due to its structure, and only a lithographic printing plate having a low printing durability was obtained from a photosensitive lithographic printing plate containing such a binder in the photosensitive layer. . On the other hand, polyvinyl acetal forms a tough film and has abrasion resistance, but has a drawback that only an organic solvent developing type photosensitive lithographic printing plate can be obtained.

Further, as a known polymer having excellent abrasion resistance, there is a polyurethane resin, which is disclosed in JP-B-49-36961 and JP-A-56-36961.
JP-94346 discloses a composition combining a diazonium compound and a substantially linear polyurethane resin, and a composition combining a diazonium salt polycondensate and a branched polyurethane resin, respectively. . However, none of these polyurethane resins has an alkali-soluble group, and their solubility in an aqueous alkaline developer is essentially insufficient, so that a photosensitive composition using this polyurethane resin as a binder is used as a photosensitive layer. It was very difficult to develop a photosensitive lithographic printing plate without developing a residual film in a non-exposed area. Furthermore, this polyurethane resin has a disadvantage that an image having sufficient strength is not formed because it does not have a site that causes a photoreaction with the combined diazonium compound at the time of exposure and is efficiently crosslinked.

On the other hand, many attempts have been made to use the photopolymerizable composition as a photosensitive image forming layer of a negative-working photosensitive lithographic printing plate.
As a binder as disclosed in JP-A-32714, a basic composition comprising a monomer and a photopolymerization initiator, and as a binder as disclosed in JP-B-49-34041, an unsaturated double Composition with improved bonding efficiency by introducing bonding, JP-B-48-38403 and JP-B-53
-27605, and compositions using a novel photopolymerization initiator as disclosed in British Patent No. 1,388,492 and the like are known, and some of them are practically used. ,
All of the photosensitive layers have the disadvantage that the sensitivity is greatly affected by the surface temperature of the photosensitive lithographic printing plate at the time of image exposure and the polymerization is strongly inhibited by oxygen at the time of image exposure.

In the past, photosensitive lithographic printing plates were often packaged in units of 20 to 50 sheets with interleaving paper sandwiched between them and supplied to users in cases, but in large quantities at once. For users to use, 500 to 1000 sheets of photosensitive lithographic printing plates must be stacked in a stack without interleaving paper, and supplied with enough pressure from the top so that they do not collapse. Are increasing in recent years. If placed in a high temperature place for a long time in such a packaging form, the surface of the photosensitive layer and the back surface of the plate stacked on it are stuck together, making it impossible for the automatic plate making machine to convey the photosensitive layer. There is a problem that the workability cannot be improved and the workability is remarkably deteriorated.

On the other hand, it is known that a fluorine-based surfactant is contained in a photosensitive composition.For example, JP-A-54-135004 discloses that a photosensitive composition dissolved or dispersed in an organic solvent is applied and dried. In order to provide a uniform photosensitive layer on a support, it is disclosed that a fluorine-based surfactant is contained in the photosensitive composition. However, the fluorinated surfactants used here do not contain any substituent containing a phosphorus atom, and even when such a surfactant is used, the sticking between the plates described above may occur. It cannot be solved. Further, JP-A-59-222843 is characterized in that a photosensitive layer containing a fluorinated surfactant and a quinonediazide compound is provided on a support, and a silicone rubber layer is provided thereon. A method for producing a negative type lithographic printing plate requiring no dampening solution is disclosed. In the present invention, the reason why the fluorine-based surfactant is added is to prevent the occurrence of uneven coating, pinholes and cissing when the coating liquid for the photosensitive layer is applied and dried on the support. It is not intended to solve the above-described problem of sticking between the plates. Because, in such a photosensitive lithographic printing plate, a silicone rubber layer or a laminate layer such as a polypropylene film is further provided on the photosensitive layer, so that the photosensitive layer is formed on the surface of the photosensitive lithographic printing plate. This is because the surface is not exposed at all and the releasability of the surface is very good, so that the problem of sticking between the plates does not originally exist. However, such a photosensitive lithographic printing plate without an overcoat layer, or a photosensitive lithographic printing plate having a dot-shaped mat layer provided on the photosensitive layer in order to shorten the vacuum adhesion time, is not required. Since at least a portion of the photosensitive layer is exposed on the surface of the photosensitive lithographic printing plate, when the plates are stacked without interposing a slip sheet, at least a portion of the surface of the photosensitive layer is stacked on the plate. The plate comes into contact with the back surface of the plate and causes the above-mentioned problem of sticking between the plates. When 50% or more of the surface area of the photosensitive layer is exposed on the surface of the photosensitive lithographic printing plate, the above-described problem of sticking between the plate and the plate is particularly prominent.

As a solution to such a problem, JP-A-61-248054 proposes that a photosensitive layer contain a surfactant having a substituent containing a perfluoroalkyl group and a phosphorus atom. However, as long as this surfactant has two substituents, a perfluoroalkyl group and a substituent containing a phosphorus atom, there are no other restrictions such as the molecular weight and the substitution rate. .

However, in a photosensitive lithographic printing plate provided with a photosensitive layer containing a polyurethane resin having a substituent having an acidic hydrogen atom, many of the surfactants described in JP-A-61-248054 are effective. Was not found.

[Object of the invention]

Therefore, an object of the present invention is to develop a plate with an aqueous alkaline developer, have good photocrosslinking properties, and have a high printing durability, and at the same time, stack the plates without inserting a slip sheet at a temperature of room temperature or higher. An object of the present invention is to provide a photosensitive lithographic printing plate in which the plates do not stick to each other even after a long period of time in the state of being hung.

[Configuration of the invention]

As a result of various studies, the present inventors have found that the photosensitive layer has a polyurethane resin having a substituent having an acidic hydrogen atom and an interface containing an average of 1.2 or more perfluoroalkyl groups per one substituent containing a phosphorus atom. The present inventors have found that the above objects can be achieved by a photosensitive lithographic printing plate containing an activator, and have reached the present invention.

 Hereinafter, the present invention will be described in detail.

The polyurethane resin used in the present invention has a substituent having an acidic hydrogen atom. A substituent having such an acidic hydrogen atom is defined as an acid dissociation constant (pK
a) points to one of 7 or less, for example -COOH, -SO ₂ NHCOO
_{-, - CONHSO 2 -, -} CONHSO 2 NH -, - NHCONHSO 2 - and the like. Particularly preferred is -COOH. The acid content per 1 g of the polyurethane resin is preferably 0.05 to 6 meq. If the amount is less than 0.05 meq, the developability with an alkali developer becomes insufficient, and if it is more than 6 meq, the abrasion resistance deteriorates. Preferably it is 0.2-4 meq.

The polyurethane resin can be produced by various methods. For example, in the case of a suitable polyurethane resin having a carboxyl group as a substituent having an acidic hydrogen atom, a diisocyanate compound represented by the following general formula (I) and a general formula (II), (III) or (IV) A polyurethane resin having, as a basic skeleton, a reaction product with the represented diol compound having a carboxyl group is exemplified.

OCN-R ¹ -NCO (I) Wherein R ¹ is a substituent (eg, alkyl, alkenyl,
Aralkyl, aryl, alkoxy and halogeno groups are preferred. A) a divalent aliphatic or aromatic hydrocarbon which may have If necessary, R ¹ may have another functional group which does not react with an isocyanate group, for example, an ester, urethane, amide, ureido group or carbon-carbon unsaturated bond.

R ² is a hydrogen atom, an alkyl, alkenyl, aralkyl, aryl, alkoxy, which may have a substituent (e.g., preferably an alkyl, aryl, alkoxy, ester, urethane, amide, ureido, halogeno group). And an aryloxy group, preferably a hydrogen atom, an alkyl group having 1 to 8 carbon atoms or an alkenyl group having 2 to 8 carbon atoms, or an aryl group having 6 to 15 carbon atoms.

R ³ , R ⁴ and R ⁵ may be the same or different,
It represents a divalent aliphatic or aromatic hydrocarbon which may have a single bond or a substituent (for example, alkyl, alkenyl, aralkyl, aryl, alkoxy and halogeno groups are preferable). It preferably represents an alkylene group having 1 to 20 carbon atoms, an arylene group having 6 to 15 carbon atoms, and more preferably an alkylene group having 1 to 8 carbon atoms. Further, if necessary, R ³ , R ⁴ , and R ⁵ have other functional groups that do not react with an isocyanate group, such as an ester group, a urethane group, an amide group, a ureido group, and a carbon-carbon unsaturated bond. Is also good.
Incidentally, two or three of R ² , R ³ , R ⁴ and R ⁵ may form a ring.

Ar represents a trivalent aromatic hydrocarbon which may have a substituent, and preferably represents an aromatic group having 6 to 15 carbon atoms.

Specific examples of the diisocyanate compound represented by the general formula (I) include the following.

That is, 2,4-tolylene diisocyanate, a dimer of 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, p-xylylene diisocyanate, m-xylylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 1,5-naphthylene diisocyanate,
Aromatic diisocyanate compounds such as 3,3'-dimethylbiphenyl-4,4'-diisocyanate; aliphatic diisocyanate compounds such as hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, lysine diisocyanate and dimer acid diisocyanate;
Alicyclic diisocyanate compounds such as isophorone diisocyanate, 4,4'-methylenebis (cyclohexyl isocyanate), methylcyclohexane-2,4 (or 2,6) -diisocyanate, 1,3- (isocyanatomethyl) cyclohexane; A diisocyanate compound which is a reaction product of a diol and a diisocyanate, such as an adduct of 1 mol of butylene glycol and 2 mol of tolylene diisocyanate.

Specific examples of the diol compound having a carboxyl group represented by the general formula (II), (III) or (IV) include the following.

That is, 3,5-dihydroxybenzoic acid, 2,2-bis (hydroxymethyl) propionic acid, 2,2-bis (2-hydroxyethyl) propionic acid, 2,2-bis (3-hydroxypropyl) propionic acid, Bis (hydroxymethyl)
Acetic acid, bis (4-hydroxyphenyl) acetic acid, 4,4-bis (4-hydroxyphenyl) pentanoic acid, tartaric acid, N,
N-bis (2-hydroxyethyl) -3-carboxy-
And propionamide.

Examples of the polyurethane resin having a substituent having an acidic hydrogen atom other than a carboxyl group include a diisocyanate compound of the general formula (I) and the following general formulas (V) and (V).
Polyurethane resins having a basic skeleton of a structure represented by a reaction product of (I), (VII) or (VIII) with a diol compound are included.

In the formula, R ² , R ³ , R ⁴ , R ⁵ and Ar are as defined above. R ⁶
Represents a monovalent aliphatic or aromatic hydrocarbon which may have a substituent (for example, preferably an alkyl, alkoxy or halogeno group). Preferred are an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an aryl group having 6 to 15 carbon atoms, and an aralkyl group having 7 to 15 carbon atoms. More preferably, an alkyl group having 1 to 8 carbon atoms,
Or an alkenyl group having 2 to 8 carbon atoms or an aryl group having 6 to 10 carbon atoms.

Y is an N-sulfonylamido group (—CO—NH—SO ₂ —),
An N-sulfonyluureido group (—NH—CO—NH—SO ₂ —),
N-aminosulfonylamide group (—CO—NH—SO ₂ —NH
-) Or a sulfonyluethane group (-O-CO-NH-SO
_2- ) is shown.

The diol compounds represented by the general formulas (V), (VI), (VII), or (VIII) include, for example, the general formulas (II), (II)
After protecting the hydroxy group of the diol compound having a carboxyl group represented by I) or (IV), the compound is reacted with a compound of the general formula (IX), (X), (XI) or (XII) in the presence of a base. Synthesized. Further, it is synthesized by reacting with chlorosulfonyl isocyanate and then reacting with an amine compound of the general formula (XIII).

R ⁶ -SO ₂ -NCO (IX) X-R ³ -CO-NH-SO ₂ -R ⁶ (X) X-R ³ -NH-CO-NH-SO ₂ -R ⁶ (XI) X-R ³ —CO—NH—SO ₂ —NH—R ⁶ (XII) R ⁶ —NH ₂ (XIII) In the formula, X represents a chlorine atom or a bromine atom.

In the case of a sulfonyluethane group, it can be synthesized by reacting one hydroxy group of a trihydroxy compound with a compound of the general formula (IX).

The compound of the general formula (X) is, for example, a reaction of the compound of the following general formulas (XIV) and (XV), and the compound of the general formula (XI) is a reaction of the compound of the following general formulas (XVI) and (XV). The compound of the general formula (XII) is obtained by reacting the following general formula (XVII) with chlorosulfonyl isocyanate,
Respectively, by the reaction with an amine compound.

^{X-R 3 -COCl (XIV)} R 6 -SO 2 -NH 2 (XV) X-R 3 -NCO (XVI) X-R 3 -COOH (XVII) The diol represented further by the general formula (VIII) The compound is, for example, a reaction between the general formula (XIV) and a compound of the following general formula (XVIII), a reaction between the general formula (XVI) and the compound of the following general formula (XVIII), a reaction between the general formula (XVIII) and chlorosulfonyl isocyanate Thereafter, the compound is synthesized by hydroxylation of each obtained compound by reaction with a compound of the following general formula (XIX).

X—R ⁴ —SO ₂ —NH ₂ (XVIII) X—R ⁴ —NH ₂ (XIX) Specifically, as a diol compound represented by the general formulas (II), (III), (IV) and (V) Includes the following.

_{(No.22) HO-CH 2 CO} -NH-SO 2 -C 3 H 6 -OH (No.23) HO-CH 2 CO-NH-SO 2 -NH-C 2 H 4 -OH (No.24 _{) HO-C 3 H 6 CO} -NH-SO 2 -NH-C 2 H 4 -OH polyurethane resin used in the present invention, a diisocyanate compound of the general formula (I) and formula (VI), (VII), or In the presence of a base, a polyurethane resin having a carboxyl group, which is a reaction product with the diol compound of (VIII),
Reacting a compound of the general formula (IX), (X), (XI) or (XII), and further reacting an amine compound of the general formula (XIII) after the reaction of the resin with chlorosulfonyl isocyanate. Can also be synthesized.

Further, a diol compound which does not have a carboxyl group and may have another substituent which does not react with isocyanate can be used in combination to such an extent that alkali developability is not reduced.

Specific examples of such diol compounds include the following.

That is, ethylene glycol, diethylene glycol,
Triethylene glycol, tetraethylene glycol,
Propylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, neopentyl glycol, 1,3-butylene glycol, 1,4-
Butanediol, 1,5-pentanediol, 1,6-hexanediol, 2-butene-1,4-diol, 2-butyne-1,4-diol, 2,2,4-trimethyl-1,3-pentane Diol, 2,2-diethyl-1,3-propanediol, 1,
4-bis-β-hydroxyethoxycyclohexane, cyclohexanediol, cyclohexanedimethanol,
Tricyclodecane dimethanol, hydrogenated bisphenol A, diethyl 2,2-dimethylolmalonate, bis 2-
(Hydroxyethyl) sulfide, hydrogenated bisphenol F, ethylene oxide adduct of bisphenol A, bisphenol A propylene oxide adduct, bisphenol F ethylene oxide adduct, bisphenol F propylene oxide adduct, hydrogenated bisphenol A ethylene oxide adduct Propylene oxide adduct of hydrogenated bisphenol A, hydroquinone dihydroxyethyl ether, p-xylylene glycol, dihydroxyethyl sulfone, bis (2-hydroxyethyl) -2,4-tolylenedicarbamate, 2,4-tolylene-
Bis (2-hydroxyethylcarbamide), bis (2-
(Hydroxyethyl) -m-xylylenedicarbamate,
Bis (2-hydroxyethyl) isophthalate and the like can be mentioned.

The polyurethane resin of the present invention can be reacted with a compound of the -OH group and the general formula of the remaining (IX), to introduce the substituent -SO ₂ NHCOO- having an acidic hydrogen atom.

The polyurethane resin of the present invention is a diisocyanate compound and a diol compound in an aprotic solvent, a known catalyst having an activity corresponding to the respective reactivity, for example, diethylaniline, 2,2,2-diazabicyclooctane, n-dibutyl It is synthesized by adding tindilaurate and the like and heating. The molar ratio of the diisocyanate and the diol compound used is preferably 0.8: 1 to 1.2: 1, and when the isocyanate group remains at the polymer terminal, the isocyanate group is finally treated by treating with an alcohol or an amine. It is synthesized without remaining.

The molecular weight of the polyurethane resin of the present invention is preferably 1,000 or more by weight average, and more preferably in the range of 5,000 to 150,000.

These polyurethane resins may be used alone or in combination. The content of these polyurethane resins contained in the photosensitive layer is 50% by weight or more, preferably 50 to 95%.
%, More preferably about 60-90% by weight.

As the basic composition of the photosensitive layer of the present invention, the polyurethane resin can be used alone, but is preferably used in a system in which the following compositions are combined. That is, (1) the polyurethane resin of the present invention and a photopolymerization initiator and / or
Or a combination system with a sensitizer; (2) a combination system with a polyurethane resin of the present invention and a diazonium compound; and (3) a monomer or oligomer having at least two ethylenically unsaturated groups polymerizable with the polyurethane resin of the present invention. (4) a polyurethane resin of the present invention and a photopolymerization initiator and / or a sensitizer;
Or a combination system of a sensitizer and a diazonium compound, (5) a monomer or oligomer having at least two ethylenically unsaturated groups polymerizable with the polyurethane resin of the present invention, a photopolymerization initiator, and / or a sensitizer and diazonium. Used in combination with compounds.

The system of (2) is particularly preferred. When used in the system (1), it is necessary to introduce a carbon-carbon unsaturated bond into the polyurethane resin.

A method for introducing a carbon-carbon unsaturated bond is disclosed in
It is described in detail in the specification of -113450.

The surfactant used in the present invention has both a perfluoroalkyl group and a substituent containing a phosphorus atom, and contains at least 1.2 perfluoroalkyl groups on average per one substituent containing a phosphorus atom. Although there are no other restrictions, the object of the present invention is not sufficiently achieved if the above conditions are not satisfied. Preferred are surfactants containing an average of 1.5 or more perfluoroalkyl groups per substituent containing a phosphorus atom.

The perfluoroalkyl group referred to here is 50% of the hydrogen atom bonded to the carbon atom of the hydrophobic group of a normal surfactant.
The above refers to those substituted with a fluorine atom.

Hereinafter, typical specific examples of the surfactant of the present invention will be described.

[C ₈ F ₁₇ SO ₂ N (R) CH ₂ CH ₂ O] _x PO [OM] _y R = C ₂ H ₅ or C ₃ H ₇ x = 1.5 or 2.0 (x + y = 3) M = H, Na, NH ₄ or NH ₂ (CH ₂ CH ₂ OH) ₂ [CHF ₂ (CF ₂ ) ₉ CH ₂ O] _x PO [OM] _y x = 1.5 or 2.0 (x + y = 3) M = H or Na [CHF ₂ ( CF ₂ ) ₇ ] _x PO [OM] _y x = 2.0 (y = 1.0) M = H or Na [C ₈ F ₁₇ CH ₂ CH ₂ O] _x PO [OM] _y x = 1.2, 1.5 or 2.0 (x + y = 3) M = H, Na, NH ₄ or NH ₂ (CH ₂ CH ₂ OH) ₂ [C ₈ F ₁₇ SO ₂ N (C ₂ H ₅ ) CH ₂ CH ₂ O] ₂ PO (OCOC ₆ H ₅ ) ₍₁ ) Examples of commercially available surfactants include Surflon S-112 manufactured by Asahi Glass Co., Ltd.

The preferred range of use of the surfactant used in the present invention is 0.01 to 10% by weight of the photosensitive layer, and 0.05 to 2% by weight.
Is particularly preferred. When the amount of the surfactant is less than 0.01% by weight, the effect of the present invention cannot be sufficiently exhibited, and when the amount is more than 10% by weight, the printing performance such as the inking property and printing durability is adversely affected.

In the photosensitive layer of the present invention, the polyurethane resin
Other resins can be incorporated in amounts of up to 50% by weight. Examples of the resin to be mixed include a polyamide resin, an epoxy resin, a polyacetal resin, an acrylic resin, a methacrylic resin, a polystyrene-based resin, and a novolac-type phenol-based resin.

When a diazonium compound is used in combination, the diazonium compound used in the present invention includes U.S. Pat.
No. 147 described diazonium compound, U.S. Pat.No. 2,632,703
And diazo resins represented by a condensate of an aromatic diazonium salt and, for example, an active carbonyl group-containing compound (eg, formaldehyde). Preferred diazo resins include, for example, hexafluorophosphate and tetrafluoroborate of a condensate of p-diazodiphenylamine and formaldehyde or acetaldehyde. Also, p as described in U.S. Pat. No. 3,300,309
A sulfonate of a condensate of diazodiphenylamine and formaldehyde (for example, p-toluenesulfonate, dodecylbenzenesulfonate, 2-methoxy-4
-Hydroxy-5-benzoylbenzenesulfonate, etc.), phosphinates (eg, benzenephosphido acid), hydroxy group-containing compound salts (eg, 2,4-dihydroxybenzophenone salt), and organic carboxylate salts are also preferable. .

Further, 3-methoxy-4-diazo-diphenylamine as disclosed in JP-A-58-27141 is condensed with 4,4'-bis-methoxy-methyl-diphenyl ether,
Mesitylene sulfonate is also suitable.
In addition, JP-A-1-102456, JP-A-1-102457, JP-A-1-254949
And diazo resins as described in JP-A Nos. 1-255246 and 2-66 can also be used.

The content of these diazonium compounds in the photosensitive layer is 1 to 50% by weight, preferably 3 to 20% by weight. If necessary, two or more diazonium compounds may be used in combination.

Various additives can be further added to the photosensitive composition used in the present invention.

For example, alkyl ethers (for example, ethyl cellulose, methyl cellulose) for improving coating properties, surfactants (for example, fluorine-based surfactants), plasticizers for imparting film flexibility and abrasion resistance (for example, , Tricresyl phosphate, dimethyl phthalate, dibutyl phthalate, trioctyl phosphate, tributyl phosphate, tributyl citrate, polyethylene glycol, polypropylene glycol, etc.), acridine dye, cyanine dye as a coloring substance for visualizing the image area after development , Styryl dyes, pigments such as triphenylmethane dyes and phthalocyanines and other general stabilizers for diazo resins (phosphoric acid, phosphorous acid, phenylphosphonic acid, pyrophosphoric acid, acid, boric acid, p-toluenesulfonic acid, benzenesulfone acid,
p-hydroxybenzenesulfonic acid, 2-methoxy-4
-Hydroxy-5-benzoyl-benzenesulfonic acid,
Malic acid, tartaric acid, dipicolinic acid, polyacrylic acid and its copolymer, polyvinylphosphonic acid and its copolymer, polyvinylsulfonic acid and its copolymer, 5-nitronaphthalene-1-phosphonic acid, 4-chlorophenoxymethylphosphone Acid, sodium phenyl-methyl-pyrazolone sulfonate, 2-phosphonobutanetricarboxylic acid-1,2,4,1-phosphonoethanetricarboxylic acid-1,2,
(2, 1-hydroxyethane-1,1-disulfonic acid, etc.) Add a fat-sensitizing agent for improving the inking property described in JP-B-62-60701 and JP-A-63-262642. You can do it. The amount of these additives varies depending on the purpose of use, but is generally 0.5 to 30% by weight based on the total solid content of the photosensitive layer.

Composition for photosensitive layer used in the present invention is dissolved in a suitable organic solvent, dry coating weight on a support having a hydrophilic surface is coated to a 0.5 to 5 g / m ^2, PS plate Can be obtained. The solid concentration of the photosensitive composition at the time of application is desirably in the range of 1 to 50% by weight. As the coating solvent used, methyl cellosolve, ethyl cellosolve, 1-methoxy-2-propanol, methyl cellosolve acetate, acetone, methyl ethyl ketone, methanol, dimethylformamide, dimethyl sulfoxide, ethylene dichloride, methyl lactate, ethyl lactate,
Examples thereof include cyclohexanone, dioxane, and tetrahydrofuran. A mixed solvent obtained by adding a mixed solvent thereof or a solvent which does not dissolve a small amount of water or a diazo resin such as toluene or a high molecular compound to the mixed solvent or the mixed solvent is also suitable. When a photosensitive solution obtained by dissolving the photosensitive composition in these solvents is applied and dried, 50 to 120 ° C.
It is desirable to dry with. Drying may be carried out at a high temperature after a preliminary drying at a lower temperature, but may be carried out directly at a high temperature by selecting an appropriate solvent and concentration.

A mat layer as described in JP-A-58-182636 may be provided on the surface of the photosensitive layer thus provided.

As the support having a hydrophilic surface to which the photosensitive composition of the present invention is applied, an aluminum plate subjected to a hydrophilic treatment is particularly preferable. Mechanical method such as wire brush graining, brush graining, ball graining, etc., which is roughened with a nylon brush while pouring slurry of abrasive particles, chemical gray, using HF, AlCl ₃ , HCl as an etchant After graining the surface by electrolytic graining using nitric acid or hydrochloric acid as an electrolytic solution or by complex graining performed by combining these surface roughening methods, the surface is grained, and if necessary, etched with an acid or alkali, and subsequently It is preferable that a strong passivation film is provided on the aluminum surface by anodic oxidation in a sulfuric acid, a phosphoric acid, an acid, a boric acid, a chromic acid, a sulfamic acid or a mixed acid thereof with a direct current or an alternating current power supply. The aluminum surface is hydrophilized by such a passivation film itself. However, if necessary, the silicate treatment (sodium silicate, sodium silicate, etc.) described in US Pat. No. 2,714,066 or US Pat.
Potassium silicate), a treatment with potassium fluorozirconate described in U.S. Pat.
3201247, phosphomolybdate treatment, British Patent 1108559, alkyl titanate treatment, German Patent 1,091,433, polyacrylic acid treatment, German Patent 1134093 No. 2,304,409, JP-B-44-6409, Phosphonic acid treatment described in U.S. Pat. A composite treatment comprising a hydrophilic organic polymer compound and a divalent metal described in JP-A-58-16893 and JP-A-58-18291;
It is particularly preferable to use a water-soluble polymer having a sulfonic acid group as described in JP-A No. 01651, which has been subjected to a hydrophilic treatment with an undercoat. U.S. Patent for other hydrophilic treatment methods
The silicate electrodeposition described in 3658662 can also be mentioned.

A PS plate having a photosensitive layer coated on a support having a hydrophilic surface can be image-exposed and then developed with a developing solution composed of weak alkaline water to obtain a negative relief image with respect to the original image.

Light sources suitable for exposure include a carbon arc lamp, a mercury lamp, a xenon lamp, a metal halide lamp, a strobe, an ultraviolet laser beam, and the like. JP-A-51-77401 as a PS plate developer having a photosensitive layer of the present invention,
JP-A-51-80228, JP-A-53-44202 and JP-A-55-52054
Organic solvents having a solubility in water of not more than 10% by weight at room temperature (benzyl alcohol,
Ethylene glycol monophenyl ether, etc.), alkalis (triethanolamine, monoethanolamine, etc.) anionic surfactants (aromatic sulfonate, dialkyl sulfosuccinate, alkylnaphthalene sulfonate, A weakly alkaline aqueous solution comprising a branched alkyl sulfate ester salt), water and, if necessary, an antifouling agent (sodium sulfite, sulfopyrazolone sodium salt, etc.) and a water softener (ethylenediaminetetraacetic acid 4Na, NCH ₂ COONa) ₃ etc. be able to.

<Example> Hereinafter, the present invention will be described in more detail with reference to examples.

Synthesis Example 1 75 g of 4,4'-diphenylmethane diisocyanate in a 500 ml three-necked round bottom flask equipped with a condenser and a stirrer
(0.3 mol), 1,6-hexamethylene diisocyanate 3
3.6 g (0.2 mol) and 67 g (0.5 mol) of 2,2-bis (hydroxymethyl) propionic acid were added and dissolved in 290 ml of dioxane. 1 g of N, N-diethylaniline was added as a catalyst, and the mixture was heated under reflux with stirring for 6 hours. Thereafter, the reaction solution was poured into a solution of 4 l of water and 40 ml of acetic acid with stirring to precipitate a white polymer. The polymer was separated by filtration, washed with water, and dried under vacuum to obtain 158 g of a polymer.

The molecular weight was measured by gel permeation chromatography (GPC) and found to be 45,000 in weight average (polystyrene standard). The content of the carboxyl group measured by titration was 2.80 meq / g.

Next, 40 g of this polymer was placed in a 300 ml three-necked round bottom flask equipped with a condenser and a stirrer, and dissolved in 200 ml of DMF. 6.46 g (0.064 mol) of triethylamine was added to this solution, and after heating to 80 ° C., 8.0 g of ethylene bromohydrin was added.
(0.064 mol) was added dropwise over 10 minutes with stirring. Thereafter, stirring was continued for 2 hours.

After completion of the reaction, the reaction solution was poured into a solution of 4 l of water and 200 ml of acetic acid with stirring to precipitate a white polymer. This polymer was separated by filtration, washed with water, and dried under vacuum to obtain 42 g of a polymer.

By NMR measurement, it was confirmed that the hydroxyethyl group was introduced into the carboxyl group, and further the residual carboxyl group content was measured by titration, 1.21meq / g
(Polyurethane (a)).

Examples 1 to 5 and Comparative Examples 1 to 4 The surface of an aluminum plate having a thickness of 0.3 mm was grained using a nylon brush and an aqueous suspension of pumicestone of 400 mesh, and then thoroughly washed with water. This was immersed in a 10% aqueous sodium hydroxide solution at 70 ° C. for 60 minutes for etching, washed with running water, and then neutralized and washed with 20% nitric acid.
No. 07 publication, ie, _VA = 12.7
Using a sinusoidal alternating waveform current of V, V _C = 9.1 V, electrolytic surface roughening treatment was performed in a 1% nitric acid aqueous solution at an anode electricity of 160 clones / dm ² . This aluminum plate was treated in a 10% aqueous sodium hydroxide solution such that the amount of aluminum dissolved was 1.2 g / m ² . Subsequently, the substrate was immersed in a 30% aqueous sulfuric acid solution and desmutted at 55 ° C. for 2 minutes, and then subjected to anodizing treatment in a 7% aqueous sulfuric acid solution so that the coating amount of aluminum oxide was 2.5 g / m ² . Thereafter, it was immersed in a 3% aqueous solution of sodium silicate at 70 ° C. for 1 minute, washed with water and dried.

A photosensitive solution having the following composition was applied to this aluminum plate so that the dry weight of the photosensitive layer was 2.0 g / m ^2, and dried to obtain photosensitive lithographic printing plates A to I.

Photosensitive solution: 5 g of polyurethane (a) of Synthesis Example 1 0.5 g of dodecylbenzene sulfonate of a condensate of 4-diazodiphenylamine and formaldehyde Dye-2 (Victoria Blue BH (Example 2) in JP-A-63-127135) Triarylmethane basic dyes) 1
-Naphthalene sulfonate) 0.1 g Malic acid 0.1 g Fc430 (3M fluorinated surfactant) 0.02 g 2-methoxyethanol 40 g Methyl alcohol 30 g Methyl ethyl ketone 30 g Interface with perfluoroalkyl group and substituent containing phosphorus atom Activator (Table 1) 0.02 g The obtained photosensitive lithographic printing plates A to I were stacked 1000 sheets each without interposing a slip sheet, and were placed under a pressure of 300 kg / cm ² at 45 ° C. for 10 days. After standing, image exposure was performed with a high-speed PS plate making machine FNR-401 manufactured by Fuji Photo Film Co., Ltd.
When plate making was performed using a processing solution obtained by diluting a developer and a gum solution formulation having the following composition 1: 1 with water, as shown in Table 1,
Automatic plate making was possible without any problem (Examples A to
E) and those in which the surface of the photosensitive layer and the back surface of the plate stacked thereon that were in contact with the photosensitive layer were stuck to each other to prevent automatic plate making (Comparative Examples F to I). It can be seen that the photosensitive lithographic printing plates A to E have very good automatic plate making suitability.

(Developer) Gum liquid formulation Urea-phosphorylated starch (raw potato starch: 15% by weight of urea added, 1.1% by weight of bound phosphorus, 20% by weight aqueous solution having a viscosity of 45 cps
(30 ° C.) 50 parts by weight, D-Sorbit 90 parts by weight,
Of sodium alkyldiphenyl ether disulfonate
5.0% by weight of 40% aqueous solution, p-oxybenzoic acid ether 0.2
Parts by weight, citric acid 2.0 parts by weight, diammonium phosphate 2.0
Parts by weight were dissolved in 790.8 parts by weight of pure water to prepare a plate surface protective agent.

Further, when a lithographic printing plate obtained by making a plate from the photosensitive lithographic printing plates A to E by the above method was printed by a GTO printing machine manufactured by Heidelberg Co., a good printed matter of 100,000 or more was obtained. Was done. On the other hand, the photosensitive lithographic printing plate F
-I also provided good printed matter of 100,000 sheets or more.

Claims (1)

(57) [Claims] 1. A photosensitive layer containing a polyurethane resin having a substituent having an acidic hydrogen atom and a surfactant having a perfluoroalkyl group and a substituent having a phosphorus atom, at least a part of which is exposed on the surface. The photosensitive lithographic printing plate as described above, wherein the surfactant contains an average of 1.2 or more perfluoroalkyl groups per one substituent containing a phosphorus atom.