JP2000089466A - Production of supporting body for photosensitive lithographic printing plate, supporting body for lithographic printing plate and photosensitive lithographic printing plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain enough eliminating property without contamination in the eliminated part during printing or without deterioration in contamination-free property of the nonpicture part by forming an anodized film on an aluminum or aluminum alloy plate and treating the plate with an aq. soln. containing fluorine and titanium. SOLUTION: After an anodized film is formed on an aluminum or aluminum alloy plate, the plate is treated with an aq. soln. containing fluorine and titanium. When the treating liquid contains zinc, the eliminating property is further improved. In this case, any form of fluorine, titanium and zinc such as single ions, complex ions and colloid may be used as far as these elements are uniformly dissolved or dispersed in the aq. soln. Further, inorg. compds. of fluorine such as potassium fluoride, acid ammonium fluoride, org. compds. such as tetrafluorosuccinate, trifluoromethane sulfonate can be used. As for titanium, inorg. compds. of titanium, for example, titanium halides such as titanium chloride, titanates such as barium titanate and compds. such as titanium oxide can be used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a support for a photosensitive lithographic printing plate. More particularly, the present invention relates to a method for producing a support for a photosensitive lithographic printing plate, which has improved erasability and does not deteriorate the stain performance caused by fingerprint traces and the stain performance caused by easy dispensing of ink during printing.

[0002]

2. Description of the Related Art A lithographic printing plate is made of aluminum or its alloy plate (hereinafter simply referred to as "aluminum plate").
The photosensitive lithographic printing plate on which the photosensitive composition is applied in a thin layer form is developed by image exposure and developed. The aluminum plate is first subjected to a surface roughening treatment, such as a mechanical method such as a brush grain method or a ball grain method, an electrochemical method such as an electrolytic grain method, or a method combining the two, and the surface thereof has a satin finish. To be. Next, the substrate is etched with an aqueous solution of an acid or an alkali, and further subjected to an anodic oxidation treatment, and then, if desired, subjected to a hydrophilic treatment to obtain a lithographic printing plate support. A photosensitive layer made of a photosensitive composition is provided on the support to form a photosensitive lithographic printing plate (so-called PS plate).

A photosensitive composition comprising an o-quinonediazide compound is widely used. Such a photosensitive substance is used alone or in an alkali-soluble resin such as a novolak-type phenol resin or a cresol resin, an acrylic resin, a polyurethane resin or the like. And the like, and then applied on a support. When a support having a hydrophilic surface is used, the exposed portion is easily removed by an alkali developing solution because the o-quinonediazide compound is decomposed and changes to alkali-soluble. As a result, the hydrophilic surface of the support is exposed, which receives water and repels the ink. On the other hand, unexposed portions remaining as images are lipophilic and accept ink. This PS version is
Usually, a lithographic printing plate is subjected to image exposure, development, correction, and gumming steps, and is mounted on a printing press for printing.

In the process of making a photosensitive lithographic printing plate, generally, a step of providing a photosensitive layer on an anodized aluminum plate, a step of exposing the photosensitive layer through a transparent original film, and a step of developing an exposed portion of the photosensitive layer are performed. The developing step of dissolving and removing with a liquid, after the developing step, remains on the anodized aluminum plate as a support due to insufficient exposure due to the edge portion of the original film or dust attached thereto, There is a correction step of erasing the photosensitive layer that should be removed with an erasing liquid. In this correction process, the length of time required for the photosensitive layer to be erased to be dissolved and erased with the erasing liquid is called erasability. If erased in a short time, the erasability is excellent, and it takes a long time to erase. Is described as poor erasability. If the erasability can be improved, the repair work can be completed in a short time, leading to an increase in work efficiency.

As a method for improving the erasability in the above-mentioned repairing process,
Conventionally, sealing treatment of the anodic oxide film of the support with hot water or steam, treatment of the anodic oxide film of the support with nitrite (JP-A-4-10989), and treatment with an inclusion compound (JP-A-8-106157) No. Gazette) has been reported. However, in these conventional erasability improving methods, the non-image area after the removal of the positive photosensitive layer is easily stained, and particularly when the tired developer is reused in the development step, the non-image area is significantly stained. Problem.

On the other hand, as a method of treating with a metal salt of an aliphatic monocarboxylic acid, a method disclosed in Japanese Patent Publication No. 7-90669 is known. In this method, a high temperature of 80 to 95 ° C. is used for 1 to 2 minutes. The purpose of this treatment is to improve the adhesion to the photosensitive layer by forming a fine structure on the surface of the anodized film. With such a support, the erasability is improved, but the stain on the non-image area during printing, especially fingerprints The stain caused by the mark is significantly deteriorated, and in some cases, the ink may adhere to the erased portion and become stained.

[0007] Further, there has long been a strong demand for a positive photosensitive lithographic printing plate to have higher durability against printing. However, a general novolak type phenol resin has a brittle coating film and has poor abrasion resistance. There were limitations in inferior applications. To solve this, for example,
Attempts have been made to use resins having urethane bonds as disclosed in JP-A-0039, JP-B-7-120040, and JP-B-7-120041. If the photosensitive layer contains 5% or more of a resin having a urethane bond shown in these known examples, the printing durability can be significantly improved up to 120 to 300% when the resin is not contained. There is a drawback that the above-mentioned erasability deteriorates remarkably due to a decrease in the property and an increase in the adsorptivity to the support. For this reason, if the erasability of a lithographic printing plate using a photosensitive layer containing a polyurethane resin can be improved, the erasability can be improved without deteriorating the printing durability, even though the number of prints is increased and the cost is greatly reduced. Cannot be achieved by the above-mentioned known examples, and it has been practically difficult to use a polyurethane resin as a binder.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for sufficiently improving the erasability of a photosensitive layer in a repairing step and also improving the easiness of staining of a non-image area. .

It is another object of the present invention to further improve the printing durability and to obtain sufficient erasability in the correction step without deteriorating both the contamination of the erased portion during printing and the difficulty of staining the non-image portion. It is to provide a method to be performed.

[0010]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above-mentioned object. As a result, after forming an anodic oxide film on an aluminum or aluminum alloy plate, the film was treated with an aqueous solution containing at least fluorine and titanium. By doing so, it has been found that the erasability of the photosensitive layer in the repairing step can be sufficiently improved, and the easiness of contamination of the non-image portion can be improved. Thus, the present invention has been completed based on this finding.

[0011] The present inventors furthermore, by adding zinc to the above-mentioned aqueous solution, or by providing a compound having an amino group or an amine layer on the prepared support, In a positive photosensitive lithographic printing plate provided with a photosensitive layer, a resin component having a urethane bond in the positive photosensitive layer is mixed with 5% of the total solid content of the photosensitive layer.
It has been found that the above object can be more preferably achieved by adding t% or more.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.

[Aluminum Support] The aluminum support used in the present invention is a dimensionally stable metal containing aluminum as a main component, and is made of aluminum or an aluminum alloy. In addition to pure aluminum plates, alloy plates containing aluminum as a main component and containing trace amounts of foreign elements,
Alternatively, it is selected from a plastic film or paper on which aluminum (alloy) is laminated or evaporated. Further, a composite sheet in which an aluminum sheet is bonded to a polyethylene terephthalate film as described in JP-B-48-18327 may be used.

In the following description, the above-mentioned plates made of aluminum or aluminum alloy are collectively referred to as aluminum plates. The different elements contained in the aluminum alloy include silicon, iron, manganese, copper, magnesium, chromium, zinc, bismuth, nickel, titanium, and the like.
The content of the foreign element in the alloy is 10% by weight or less. In the present invention, a pure aluminum plate is preferable, but completely pure aluminum is difficult to produce due to smelting technology, and therefore may contain a slightly different element. As described above, the composition of the aluminum plate applied to the present invention is not specified.
IS A 1050, JIS A 1100, JIS A 3
103, JIS A 3005, etc. can be used as appropriate.

The aluminum plate used in the present invention is usually processed while continuously running in the form of a web, and has a width of about 400 mm to 2000 mm and a thickness of about 0.2 mm.
It is about 1 mm to 0.6 mm. This thickness can be appropriately changed according to the size of the printing press, the size of the printing plate, and the user's request.

The aluminum plate is appropriately subjected to a substrate surface treatment described later.

[Graining] The graining method includes mechanical graining, chemical etching and electrolytic graining as disclosed in JP-A-56-28893. Furthermore, an electrochemical graining method in which the aluminum surface is electrochemically grained in a hydrochloric acid or nitric acid electrolyte, a wire brush graining method in which the aluminum surface is scratched with a metal wire, and a ball graining method in which the aluminum surface is grained with a polishing ball and an abrasive. Alternatively, a mechanical graining method such as a brush grain method for graining the surface with a nylon brush and an abrasive can be used, and the above graining methods can be used alone or in combination.

Among them, a method for producing a surface roughness usefully used in the present invention is an electrochemical method in which the surface is chemically grained in a hydrochloric acid or nitric acid electrolytic solution.
00 to 400 C / dm ² , preferably 150 to 300 C
/ Dm ² . More specifically, 0.1 to 5
In an electrolyte containing 0% by weight, preferably 0.5 to 10% by weight of hydrochloric acid or nitric acid, at a temperature of 20 to 100 ° C, preferably 30 to 70 ° C, for a time of 1 second to 30 minutes, preferably 2 seconds to 1 hour.
The electrolysis is preferably performed under the conditions of a current density of 100 to 400 C / dm ² .

The grained aluminum plate is chemically etched with an acid or an alkali. When an acid is used as an etching agent, it takes time to destroy a fine structure, which is disadvantageous in industrially applying the present invention. However, it can be improved by using an alkali as an etching agent.

The alkaline agent preferably used in the present invention includes caustic soda, sodium carbonate, sodium aluminate, sodium metasilicate, sodium phosphate, potassium hydroxide, lithium hydroxide, and the like. 1 to 50% by weight, especially 2 to 20% by weight, 20 to 10%
0 ° C., especially 30 to 70 ° C., and the amount of Al dissolved is 5 to 2
It is preferable that the condition be 0 g / m ² .

After the etching, pickling is performed to remove dirt (smut) remaining on the surface. As the acid used, nitric acid, sulfuric acid, phosphoric acid, chromic acid, hydrofluoric acid, borofluoric acid and the like are used. In particular, as a method for removing the smut after the electrochemical surface-roughening treatment, it is preferable to use a method of removing 50 to 50 as described in JP-A-53-12739.
A method of contacting with sulfuric acid of 15 to 65% by weight at a temperature of 90 ° C. and a method of alkali etching described in Japanese Patent Publication No. 48-28123 are exemplified.

[Anodizing treatment] The aluminum plate thus treated is subjected to anodizing treatment. The anodizing treatment can be performed by a method conventionally performed in this field. Specifically, sulfuric acid, phosphoric acid, oxalic acid,
And the like are mainly used as an electrolytic bath. In some cases, chromic acid, sulfamic acid, benzenesulfonic acid, or the like, or an aqueous solution or a non-aqueous solution in which two or more of these are combined may be used. An anodic oxide film can be formed on the surface of the aluminum support by applying a direct current or an alternating current to aluminum in the electrolytic bath as described above.

The conditions of the anodic oxidation treatment vary depending on the electrolytic solution to be used, and thus cannot be unconditionally determined. In general, the concentration of the electrolytic solution is 1 to 80% by weight, preferably 5 to 80% by weight.
20% by weight, liquid temperature 5 to 70 ° C, preferably 10 to 60
° C, current density 0.5 to 60 A / dm ² , preferably 1 to
30 A / dm ² , voltage 1 to 100 V, preferably 5 to 5
0 V, electrolysis time 10 to 100 seconds, preferably 20 to 60
A range of seconds is appropriate.

Among these anodizing treatments, those described in GB 1,412,768 are particularly useful.
A method of performing anodic oxidation at a high current density in sulfuric acid is preferred.

In the present invention, the anodic oxide film has a thickness of 1-1.
It is preferably 0 g / m ² , and if it is 1 g / m ² or less, the plate is easily damaged, and if it is 10 g / m ² or more, a large amount of power is required for production, which is economically disadvantageous. Preferably, it is 1.5 to 7 g / m ² . More preferably, 2-5
g / m ² .

[Treatment with an aqueous solution containing fluorine and titanium] After the anodizing treatment, immersion treatment is performed with an aqueous solution containing fluorine and titanium. At least fluorine and titanium are required in the processing solution, but if zinc is present, the erasability is further improved. At this time, fluorine, titanium, and zinc may be in any form such as a simple ion, a complex ion, and a colloid as long as they are dissolved or uniformly dispersed in an aqueous solution.

Fluorine is an inorganic compound such as potassium fluoride, ammonium acid fluoride, zinc fluoride, potassium fluoride, potassium zirconium fluoride, strontium fluoride, copper fluoride, sodium fluoride, magnesium fluoride, and fluoride. Salts of barium, lithium fluoride, tin fluoride, ammonium fluoride, aluminum trifluoride, etc., potassium titanium fluoride, (potassium hexafluorotitanate), hexafluorosilicic acid, ammonium hexafluorosilicate, potassium hexafluorosilicate, hexa Sodium fluorosilicate, ammonium hexafluorotitanate, ammonium hexafluorogermanate (IV), potassium hexafluorozirconate, ammonium hexafluorophosphate, potassium hexafluorophosphate, lithium hexafluorophosphate Hexafluoro inorganic acid salts such as sodium, trifluoro compounds such as sodium trifluoroborate, tetrafluoro compounds such as ammonium tetrafluoroborate and tetrafluoroferrate, and organic compounds such as tetrafluorosuccinate and trifluorofluoride Lomethanesulfonic acid, hexafluoroisopropanol and the like can be used.

Titanium is an inorganic compound such as titanium chloride (I
Titanium halides, potassium titanium fluoride, etc.
(Potassium hexafluorotitanate), titanates such as ammonium hexafluorotitanate and barium titanate, and compounds such as potassium titanium oxalate, titanium sulfate and titanium oxide can be used.

As zinc, for example, compounds such as zinc sulfate, zinc chloride and zinc acetate, zinc oxalate, zinc nitrate, zinc carbonate, zinc lactate, zinc fluoride, zinc phosphate and zinc tartrate can be used.

Other added elements and compounds may be simultaneously present in the aqueous solution. As the concentration, the concentration of fluorine is about 0.0001 to 10 g / l as an element,
Preferably about 0.001 to 5 g / l is appropriate. The concentration of titanium is about 0.0001 to 10 g / l as an element, preferably about 0.001 to 5 g / l. Further, the concentration of zinc is 0.0005 to 5 g as an element.
/ L, preferably about 0.1 / l.
It is in the range of 001 to 2 g / l. Processing temperature is 10 to 80
° C, preferably 20 to 60 ° C. Immersion treatment time is 1
３００300 seconds, preferably 5-60 seconds. After the anodizing treatment, the substrate is washed with water, treated under the above conditions and dried. What is necessary is just to bring the aqueous solution containing at least fluorine and titanium into contact with the surface of the aluminum plate having the anodic oxide film, and for the treatment, it is also possible to cover the surface with a sponge or a waste moistened with this aqueous solution.

A photosensitive layer is provided on the aluminum plate which has been subjected to the above-mentioned treatment, and a hydrophilic undercoat layer may be provided if necessary.

[Hydrophilic undercoat layer] The hydrophilic undercoat layer used in the present invention comprises, for example, at least one amino group disclosed in JP-A-60-149491;
A hydrophilic layer comprising a compound having a carboxyl group and a salt group thereof and at least one group selected from the group consisting of a sulfo group and a salt group thereof, JP-A-60-23299
JP-A No. 62-194, disclosed in Japanese Patent Application Laid-Open No. Sho 62-194, disclosed in JP-A-62-194
No. 94, a hydrophilic layer containing a phosphate, and a polymer compound containing at least one kind of a monomer unit having a sulfo group disclosed in JP-A-59-101651 as a repeating unit in a molecule. A hydrophilic layer consisting of R as disclosed in JP-A-4-282637.
¹ (PO (OH) ₂ ) _n or R ^1- (PO (OH)
(R ²⁾⁾ aliphatic substituted or unsubstituted represented by _n compounds or aromatic compounds (n is 1 or 2, n = 1 when R ^1, R ² is a substituted or unsubstituted alkyl group, Represents an alkoxy group, an aryloxy group, an aryl group, an acyl group, or an acyloxy group. When n = 2, R ¹ represents a substituted or unsubstituted alkylene group or an arylene group, and R ² is as defined above. And an organic layer containing at least one compound selected from the group consisting of the following compounds. Preferred are compounds having an amino group and amines. Examples thereof include amino acids and their salts (such as alkali metal salts such as Na salts and K salts, ammonium salts, and hydrochlorides) disclosed in JP-A-60-149491. Oxalates, acetates, phosphates, etc.), amines having a hydroxyl group and their salts (hydrochlorides, oxalates, acetates, phosphates, etc.) disclosed in JP-A-60-232998; 63-165183
And compounds having an amino group and a phosphonic acid group, or salts thereof, disclosed in Japanese Patent Application Laid-Open Publication No. H11-163,036. The application amount is 0.1
About 100 mg / m ² is appropriate.

[Photosensitive layer] As the composition of the photosensitive layer used in the present invention, any composition can be used as long as its solubility or swelling property in a developer changes before and after exposure. Hereinafter, representative ones will be described.

Examples of the photosensitive compound of the positive photosensitive composition include an o-quinonediazide compound, and a representative example thereof is an o-naphthoquinonediazide compound.

The o-naphthoquinonediazide compound is preferably an esterified compound of 1,2-diazonaphthoquinonesulfonic acid chloride and pyrogallol-acetone resin described in JP-B-43-28403. Other suitable o-quinonediazide compounds include U.S. Pat. Nos. 3,046,120 and 3,18.
There is an ester of 1,2-diazonaphthoquinone sulfonic acid chloride and phenol-formaldehyde resin described in U.S. Pat. No. 8,210. Other useful o
-Naphthoquinonediazide compounds include those reported and known in numerous patents. For example, JP-A-47-5303, JP-A-48-63802,
No. 48-63803, No. 48-96575, No. 49
No. 38701, No. 48-13354, Japanese Patent Publication No. 37-
No. 18015, No. 41-11222, No. 45-961
Nos. 0 and 49-17481, U.S. Pat.
No. 97,213, No. 3,454,400, No. 3,
Nos. 544,323, 3,573,917, 3,674,495, 3,785,825, British Patents 1,227,602 and 1,251,34.
No. 5, No. 1,267,005, No. 1,329,88
No. 8, No. 1, 330, 932, German Patent No. 85
No. 4,890 and the like can be mentioned.

An o-naphthoquinonediazide compound obtained by reacting a polyhydroxy compound having a molecular weight of 1,000 or less with 1,2-diazonaphthoquinonesulfonic acid chloride can also be used. Specific examples of such compounds are described in JP-A-51-139402 and JP-A-58-15094.
No. 8, No. 58-203434, No. 59-165053
No., No. 60-112445, No. 60-134235
No., No. 60-163443, No. 61-118744
Nos. 62-10645, 62-10646, 62-153950, 62-178562, and 6
4-76047, U.S. Pat. No. 3,102,809,
No. 3,126,281, No. 3,130,047,
No. 3,148,983, No. 3,184,310, No. 3,188,210, No. 4,639,406 and the like, each of which is described in each gazette or specification. be able to.

When synthesizing these o-naphthoquinonediazide compounds, it is preferable to react 0.2 to 1.2 equivalents of 1,2-diazonaphthoquinonesulfonic acid chloride with respect to the hydroxy groups of the polyhydroxy compound.
More preferably, the reaction is performed in an amount of 0.3 to 1.0 equivalent.
As the 1,2-diazonaphthoquinonesulfonic acid chloride, 1,2-diazonaphthoquinone-5-sulfonic acid chloride is preferred, but 1,2-diazonaphthoquinone-4-chloride is preferred.
Sulfonyl chloride can also be used.

The resulting o-naphthoquinonediazide compound is a mixture of various 1,2-diazonaphthoquinonesulfonic acid ester groups having different positions and amounts of introduction, but all the hydroxyl groups are 1,2-diazonaphthoquinonesulfonic acid esters. The ratio of the compound converted to the above to the mixture (the content of the completely esterified compound) is preferably 5 mol% or more, more preferably 20 to 99 mol%.

As a photosensitive compound which acts positively without using an o-naphthoquinonediazide compound, for example, a polymer compound having an o-nitrocarbinol ester group described in JP-B-56-2696 is also included in the present invention. Can be used.

A compound capable of generating an acid by photolysis,
-CO-C- group or -CO-Si dissociated by acid
A combination system with a compound having a group can also be used in the present invention.

For example, a combination of a compound capable of generating an acid by photolysis with an acetal or an O, N-acetal compound (Japanese Patent Application Laid-Open No. 48-89003), a combination with an orthoester or an amide acetal compound (Japanese Patent Application Laid-Open No. 1
20714), a combination with a polymer having an acetal or ketal group in the main chain (JP-A-53-13342).
No. 9), a combination with an enol ether compound (JP-A-55-12995), a combination with an N-acylimino carbon compound (JP-A-55-126236),
Combination with a polymer having an orthoester group in the main chain (JP-A-56-17345), combination with a silyl ester compound (JP-A-60-10247) and combination with a silyl ether compound (JP-A-60-17247) 60-375
49, JP-A-60-112446) and the like.

The amount of these positive-acting photosensitive compounds (including the above combinations) in the photosensitive composition of the present invention is suitably from 10 to 50% by weight, more preferably from 15 to 50% by weight. 40% by weight.

The o-quinonediazide compound alone can constitute the photosensitive layer, but is preferably used together with a resin soluble in alkaline water as a binder. Such resins soluble in alkaline water include novolak resins having this property, such as phenol formaldehyde resin, m-cresol formaldehyde resin, p-cresol formaldehyde resin, and m- / p.
-Mixed cresol formaldehyde resin, phenol /
Cresol (may be m-, p-, or m- / p-mixed) Cresol formaldehyde resin such as mixed formaldehyde resin, phenol-modified xylene resin, polyhydroxystyrene, polyhalogenated hydroxystyrene, JP-A-51-34711 Acrylic resin containing a phenolic hydroxyl group as disclosed in
Various alkali-soluble polymer compounds such as an acrylic resin having a sulfonamide group described in JP-A-2-866 and a urethane-based resin can be contained.
These alkali-soluble polymer compounds have a weight average molecular weight of 500-20,000 and a number average molecular weight of 200-6.
000 is preferred.

Such an alkali-soluble polymer compound is used in an amount of not more than 70% by weight of the total composition.

Further, as described in US Pat. No. 4,123,279, a compound having an alkyl group having 3 to 8 carbon atoms as a substituent, such as a t-butylphenol formaldehyde resin and an octylphenol formaldehyde resin. It is preferable to use a condensate of phenol and formaldehyde or an o-naphthoquinonediazidosulfonic acid ester of these condensates (for example, those described in JP-A-61-243446) in order to improve the oil sensitivity of an image. .

In the photosensitive composition of the present invention, a cyclic acid anhydride for increasing the sensitivity, a printing-out agent for obtaining a visible image immediately after exposure, a dye or other filler as an image coloring agent, and the like are included. Can be added. The cyclic acid anhydride U.S. Pat phthalic anhydride as described in 4,115,128 Pat, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, 3,6-oxy - [delta ⁴ -
Examples include tetrahydrophthalic anhydride, tetrachlorophthalic anhydride, maleic anhydride, chloromaleic anhydride, α-phenylmaleic anhydride, succinic anhydride, and pyromellitic anhydride. By containing these cyclic anhydrides in an amount of 1 to 15% by weight based on the total weight of the composition, the sensitivity can be increased up to about three times. As a printing-out agent for obtaining a visible image immediately after exposure, a combination of a photosensitive compound that releases an acid upon exposure and an organic dye capable of forming a salt can be exemplified.

Specifically, o-type compounds described in JP-A-50-36209 and JP-A-53-8128 are disclosed.
Combinations of naphthoquinonediazide-4-sulfonic acid halide and salt-forming organic dyes and JP-A-53-36223, JP-A-54-74728, JP-A-60-3626, and JP-A-61-1
No. 43748, No. 61-151644, No. 63-58
No. 440, and combinations of trihalomethyl compounds and salt-forming organic dyes. Other dyes besides the above-mentioned salt-forming organic dyes can be used as image coloring agents. Suitable dyes, including salt-forming organic dyes, include oil-soluble dyes and basic dyes. Specifically, Oil Yellow # 101, Oil Yellow # 130, Oil Pink # 312, Oil Green BG, Oil Blue BOS, Oil Blue # 60
3. Oil black BY, oil black BS, oil black T-505 (all manufactured by Orient Chemical Industries, Ltd.), Victoria Pure Blue, crystal violet (CI142555), ethyl violet (CI
42600), methyl violet (CI42535),
Rhodamine B (CI45170B), malachite green (CI42000), methylene blue (CI5201)
5) and the like. Also, JP-A-62-29
The dyes described in 3247 are particularly preferred.

In the present invention, the photosensitive composition is dissolved in a solvent capable of dissolving each of the above components and applied on a support. As the solvent used here, ethylene dichloride, cyclohexanone, methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2-methoxyethyl acetate, 1-methoxy-2-propanol, 1-methoxy-2-propyl acetate, toluene , Ethyl acetate, methyl lactate, ethyl lactate, dimethyl sulfoxide, dimethylacetamide,
Examples include dimethylformamide, water, N-methylpyrrolidone, tetrasdrofluryl alcohol, acetone, diacetone alcohol, methanol, ethanol, isopropanol, diethylene glycol, and dimethyl ether. These solvents are used alone or in combination. The concentration (solid content) of the above components in the solution is 2 to 50.
% By weight. The coating amount varies depending on the application, but for example, in the case of a photosensitive lithographic printing plate, it is generally preferable that the solid content be 0.5 to 3.0 g / m ² . As the amount of coating decreases, the photosensitivity increases, but the physical properties of the photosensitive film deteriorate.

In the photosensitive composition of the present invention, a surfactant for improving coating properties, for example, JP-A-62-1
A fluorine-based surfactant as described in JP-A-70950 can be added. A preferable addition amount is 0.01 to 1% by weight, more preferably 0.05 to 0.5% by weight of the whole photosensitive composition.

The thickness of the photosensitive layer can be 0.1 to 30 μm, more preferably 0.5 to 10 μm. The amount of the photosensitive layer provided on the support (fixed frequency) from about 0.1 to about 7 g / m ^2, preferably in the range of 0.5-4 g / m ^2. The surface of the photosensitive layer provided as described above is preferably matted in order to shorten the time for evacuation during contact exposure using a vacuum printing frame and to prevent printing blur. Specifically, a method of providing a mat layer as described in JP-A-50-125805, JP-B-57-6582 and JP-B-61-28986 is described in JP-B-62-62337. And a method of thermally fusing such a solid powder. After the imagewise exposure of the photosensitive lithographic printing plate of the present invention, the lithographic printing plate is made into a lithographic printing plate by a process including development by a conventional method.

In the case of a positive type lithographic printing plate, after image exposure,
U.S. Pat. No. 4,259,434 and JP-A-3-903.
By developing with an alkaline aqueous solution as described in JP-A-88-88, the exposed portion of the photosensitive layer is removed to obtain a lithographic printing plate.

The photosensitive lithographic printing plate of the present invention is disclosed in
JP-A-8002, JP-A-55-115045 and JP-A-59-15045.
It goes without saying that the plate-making process may be performed by the method described in each of the publications of No. 58431. That is, after the development processing,
A desensitization treatment after washing with water, a desensitization treatment as it is, a treatment with an aqueous solution containing an acid, or a treatment with an aqueous solution containing an acid may be followed by a desensitization treatment. Furthermore, in the development process of this type of photosensitive lithographic printing plate, the alkali aqueous solution is consumed depending on the processing amount, and the alkali concentration is reduced, or the alkali concentration is reduced by air due to long-time operation of the automatic developing solution. The processing capacity is reduced. At this time, a fresh unused developer (replenisher) is added, or processing is performed using a replenisher having a high alkalinity as described in JP-A-54-62004. You may restore your abilities. In this case, a method of adding a replenisher in an amount proportional to the length of one piece of the PS plate to be processed or US Pat.
It is preferred to replenish by the method described in US Pat. No. 2,246.

The plate making process described above is disclosed in
It is preferably carried out using an automatic developing machine as described in JP-A-7054 and JP-A-2-32357.

Further, when the photosensitive lithographic printing plate of the present invention is subjected to image exposure, development, washing or rinsing, and then unnecessary image portions are to be erased, it is described in JP-B-2-13293. It is preferable to use such an erasing liquid. Examples of the desensitized gum which is applied as required in the final step of the plate making process include JP-B-62-16834, JP-B-62-25118, JP-B-63-52600 and JP-A-6-52600.
Nos. 2-7595, 62-11693 and 62-83
What is described in each gazette of No. 194 is preferable.

Further, when the photosensitive lithographic printing plate of the present invention is subjected to image exposure, development, washing or rinsing, erasing if desired, and washing with water, and then burning, before burning, the lithographic printing plate is prepared before burning. No. 2518, 55-2806
No. 2, JP-A Nos. 62-31859 and 61-15965.
It is preferable to carry out treatment with a surface-regulating liquid as described in each publication of No. 5.

Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. However, the present invention is not limited to the examples, and particularly for the photosensitive layer, an acrylic resin other than the novolak resin, urethane It can be easily applied to resins.

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EXAMPLE The surface of an aluminum plate having a thickness of 0.30 mm was grained with a nylon brush and an aqueous suspension of pumicestone of 400 mesh, and then washed thoroughly with water. 1
After being immersed in 0% sodium hydroxide at 70 ° C. for 60 seconds for etching, it was washed with running water. Then, 20% HNO
Washing with neutralization and washing with ₃ were performed. This was subjected to electrolytic surface roughening treatment in a 1% nitric acid aqueous solution at an anode electricity of 260 coulombs / dm ² using a sine wave alternating current under the condition of V _A = 12.7 V. The surface roughness was measured to be 0.55.
μ (Surfcom 575, cutoff manufactured by Tokyo Seimitsu)
0.8, Ra display using a stylus of 2 μmR).
Then immersed in a 30% aqueous solution of H ₂ SO ₄ at 55 ° C.
And then anodized at 33 ° C. in a 15% H ₂ SO ₄ aqueous solution at a current density of 5 A / dm ² for 45 seconds.
A substrate was prepared.

After that, the substrate was immersed under the conditions shown in Table 2, washed with running water, air-dried, and then adjusted to a coating amount of 10 mg / m ² as a solid of the following undercoat liquid. It was applied by rod coating and dried at 100 ° C. for 20 seconds.

[Undercoat liquid] Pure water 5 g Methyl alcohol 95 g β-alanine 0.16 g

Next, the following photosensitive solution was applied by rod coating at 25 ml / m ^{2 and} dried at 100 ° C. for 1 minute to obtain a positive photosensitive lithographic printing plate. The coated amount after drying was about 1.5 g / m ² .

[Photosensitive solution] Esterified product of 1,2-diazonaphthoquinone-5-sulfonyl chloride and pyrogallol-acetone resin (as described in Example 1 of US Pat. No. 3,635,709) 0.90 g Phenol / p-cresol aldehyde resin having a weight average molecular weight of 7,000 (phenol / p-cresol molar ratio: 5/5, containing 0.7% g of unreacted cresol) 1.30 g Using the indicated diisocyanate and diol compounds, a polyurethane resin having a carboxyl group (molecular weight was 47000 in terms of weight average (polystyrene standard)) synthesized in the same manner as in Synthesis Example 1 in Examples of JP-B-7-120039. M-cresol-formaldehyde novolak resin (weight average molecular weight 1,700, number average molecular weight 60) 0.3 g P-normal octylphenol-formaldehyde resin (described in U.S. Pat. No. 4,123,279) 0.02 g naphthoquinonediazide-1,2- Diazide-4-sulfonic acid chloride 0.01 g Tetrahydrophthalic anhydride 0.02 g Dye in which the counter anion of Victoria Pure-BOH [manufactured by Hodogaya Chemical Co., Ltd.] is changed to 1-naphthalenesulfonic acid 0.05 g Megafac F- 176 (fluorinated surfactant manufactured by Dainippon Ink and Chemicals, Inc.) 0.01 g methyl ethyl ketone 55 g

Based on the method described in Example 1 of JP-B-61-28986, a plate of (methyl methacrylate / ethyl acrylate / sodium acrylate: 68/20/12) was placed on the plate thus coated. A mat layer was provided by dissolving 0.1 g of tartrazine in 100 g of the aqueous copolymer solution and electrostatically spraying.

Using the photosensitive lithographic printing plate thus obtained as a light source, a 2KW metal halide lamp (idle fin manufactured by Iwasaki Electric Co., Ltd.) was used, and the exposure time was adjusted to four steps by a step guide manufactured by Fuji Photo Film Co., Ltd. It was adjusted. After the exposure, the planographic image quality of the printing plate was visually evaluated, and as a developing solution, DP-4 (9) manufactured by Fuji Photo Film Co., Ltd. was used.
Double-dilution) was passed through an automatic developing machine, Stavlon 900V, manufactured by Fuji Photo Film Co., Ltd., in which FR-3 manufactured by Fuji Photo Film Co., Ltd. was charged as a finisher solution. The details were as described in the explanation of the treatment liquid.

After erasing and rinsing the image area as necessary,
Processing was performed through a gum coater G800H manufactured by Fuji Photo Film Co., Ltd. charged with a gum solution GU-7 manufactured by Fuji Photo Film.

On the other hand, Table 3 shows the results of production evaluation in the same manner as in Example 2 except that the components of the undercoat liquid were changed. Excluding the polyurethane resin, the amount of the phenol / p-cresol aldehyde resin having a weight average molecular weight of 8000 (phenol / p-cresol molar ratio: 5/5, containing 0.7% of unreacted cresol) was 1. Table 4 shows the results of production evaluation in the same manner as in Example 1 except that the treatment after the anodizing treatment was performed under the conditions shown in Table 4 with the photosensitive layer formulation of 60 g.

<Evaluation method> Erasability: The image area of the printing plate after development was dissolved with an erasing solution (erasing solution RP-2, manufactured by Fuji Photo Film Co., Ltd.) until the photosensitive layer appeared to be completely removed. Time (time during which the remaining photosensitive layer in the image area cannot be completely discriminated) Print smear: When water supply and paper feed are started simultaneously with the printing plate attached to the offset printing machine and ink applied to the entire surface of the plate, Initially, ink adheres to the portion corresponding to the non-image portion on the printed matter and becomes stained, but as printing progresses, the ink is removed and eventually the original non-image where the ink does not adhere to the printed matter. Department. In particular, the number of damaged sheets up to this state regarding the stain on the erased non-image portion is used as an index of print stain. Printing durability: Printed on high quality paper using a commercially available ink with a Lithrone printing machine manufactured by Komori Corporation, and the number of printed sheets when the density of the solid image began to decrease was examined.

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[Table 1]

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[Table 2]

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[Table 3]

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[Table 4]

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According to the present invention, it is possible to provide a photosensitive lithographic printing plate support having excellent erasability of the photosensitive layer in the repairing step and excellent stain performance of the non-image area.

Claims (4)

[Claims] 1. A method for producing a photosensitive lithographic printing plate support, comprising: forming an anodic oxide film on an aluminum or aluminum alloy plate; and treating the plate with an aqueous solution containing at least fluorine and titanium. 2. The method for producing a photosensitive lithographic printing plate support according to claim 1, wherein the aqueous solution further contains zinc. 3. A lithographic printing plate support comprising a support treated by the method according to claim 1 and a compound having an amino group or an amine layer provided on the support. 4. A positive photosensitive lithographic printing plate comprising a lithographic printing plate support according to claim 3 and a photosensitive layer provided on the support, wherein a resin component having a urethane bond in the positive photosensitive layer comprises a photosensitive layer. A photosensitive lithographic printing plate comprising 5 wt% to 25 wt% of the total solids.