JPS61177450A - Photosensitive lithography plate - Google Patents

Abstract

PURPOSE:To improve a durability of the titled plate against a treating chemicals by applying a photosensitive composition contg. o-quinone diazido sulfonic acid ester of a polycondensation resin of a compd. having a specific structure and an aldehyde or a ketone to a sensitive layer. CONSTITUTION:Said o-quinone diazido sulfonic acid ester is prepared by condensating o-quinone diazido sulfonic acid ester and the polycondensate of a compd. shown by the formula and the aldehyde or the ketone. Said ester has at least one of o-quinone diazido sulfonyl group and an average mol.wt. of 5.00X10<2>-4.00X10<3> range. The substrate is an Al plate treated with an anodic oxidation on a base plate. The photosensitive layer is provided on said substrate in such a way that the coated surface treated with the anodic oxidation forms a surface of the titled plate having a specific surface state. A roughness of the surface of the substrate is 2.0mum a cutting depth of a profile R. A peak count S1, S2 and a bur count T1, T2 of the Al substrate has a following relation 30<S2<400:S1, T1 and T2<30.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a photosensitive lithographic printing plate, and more particularly to a photosensitive lithographic printing plate that has high sensitivity and a large dot reduction effect. .

(Background of the Invention and Prior Art) It is known that when an 0-quinonediazide compound is irradiated with actinic rays, it decomposes to produce indenecarboxylic acid, which becomes alkali-soluble. Therefore, 0-quinonediazide compounds are widely used in lithographic printing plate materials as photosensitive components for producing positive-type images.

However, photosensitive lithographic printing plates using photosensitive compositions containing 0-quinone di7dide compounds have low sensitivity, and therefore require a long time for exposure during plate-making work, reducing work time and improving work efficiency. number is requested.

In addition, good prints (especially color prints) cannot be obtained unless the film original is faithfully reproduced on printing paper, but with lithographic printing plates, the dots in the halftone image area on the printing plate are Due to the pressure, the area becomes larger (hereinafter referred to as "dot thickening") and printed on the printing paper. Therefore, in order to correct this dot thickening and faithfully reproduce the halftone dots of the film original on printing paper, the halftone dots of the film original are corrected.

When printing with light photolithographic printing plate K11l light, the area of the halftone dot image area on the plate after development is smaller than the halftone dots of the film original (hereinafter referred to as "
It is necessary to reproduce the result (called a point deduction).

Normally, in order to reduce this point, printing is performed using a longer exposure time than the appropriate exposure time. For this reason,
In order to improve work efficiency, a photosensitive lithographic printing plate that has a sufficient dot reduction effect even with short exposure is desired.

Attempts to improve the sensitivity and dot reduction effect of photosensitive lithographic printing plates using photosensitive compositions containing 0-quinone di7dide compounds include, for example, JP-A-57-118237 and JP-A-59-15244. The publication describes a method of increasing the sensitivity and dot reduction effect by adding gallic acid or its derivatives to the photosensitive layer, but this method does not include various processing chemicals used during printing operations, especially those containing acids. Processing chemicals, such as Ultra Plate Cleaner (A, B,
C. (manufactured by Chemical Co., Ltd.)).

On the other hand, as an attempt to improve the dot reduction effect by devising the support, Japanese Patent Application Laid-Open No. 162693/1983 discloses that the amount of anodized film on the aluminum support of a photosensitive lithographic printing plate was increased from 25,119/dm" to 50/dm". dffl'' is described. However, the effect of point reduction by this method is not significant and does not have the effect of increasing sensitivity. Furthermore, JP-A-54-92804 discloses a technique for increasing the effective sensitivity (point reduction effect) by using an aluminum support having a specific center line average surface roughness (Ra) and a surface reflectance above a specific value. is listed. However, even if an aluminum support with a high surface reflectance is used, the dot reduction effect is not necessarily improved, and even if it is improved, it is not significant.

In addition, Japanese Patent Application Laid-Open No. 58-167196 discloses that an aluminum support having grains expressed by a specific pore size distribution and a specific directional dependence of roughness is used to create continuous-tone manuscripts. Although a technology for manufacturing without taking pictures is described, the sensitivity and dot reduction effect are not improved. Also, Japanese Patent Application Publication No. 1973-
Publication No. 133903 uses an aluminum support characterized by the depth of the grain defined by the center line average roughness, and the average diameter and distribution of the openings on the surface of the grain. Techniques to improve this are described. However, this technique has the drawback that the point reduction effect is extremely poor. Furthermore, JP-A-56-47041 describes a technique for increasing sensitivity by using an aluminum support that has been electrolytically etched in a nitric acid bath, alkaline etched, and anodized; Similarly, there is a drawback that the point reduction effect is poor. Also, Japanese Patent Application Publication No. 1973
Publication No. 103102 describes a technique using an aluminum support which is grained, anodized, and then reacted with a silicate aqueous solution and an anodic oxide film.

This promotes the solubility of non-image areas during development and improves developability, but does not have a dot reduction effect. Furthermore, JP-A-55
JP-A-137993 describes a technique using an aluminum support grained by a combination of mechanical polishing and electrolytic etching. This technique increases the water retention and reflectance of the support, but does not contribute to improved sensitivity or point reduction effects.

(Object of the Invention) Therefore, an object of the present invention is to provide a photosensitive lithographic printing plate which is highly sensitive, has a remarkable dot reduction effect, and has excellent durability against processing chemicals.

(Structure of the Invention) The object of the present invention is to obtain a peak count (Sl.

S2) and Barry Count (Tt eT2) are 30
<82<400, 8. , T1. T2 < 30
O-quinonediazide sulfonic acid, which is a polycondensation resin of at least one compound selected from the following general formula (1) and aldehyde or ketone, is placed on a support made of anodized aluminum material as a base material. Ester (weight average molecular weight 5.00 x 102 - 4.00 x l
This is achieved by a photosensitive lithographic printing plate provided with a photosensitive composition containing □a) as a photosensitive layer.

General formula [I] L3 In the formula, s R1 represents a hydrogen atom, a hydroxy group, or a halogen atom, and R2 represents a hydrogen atom, a hydrogen atom, a lower fulkyl group having 1 to 4 carbon atoms, or a lower fulkyl group having 1 to 4 carbon atoms. represents a flukoxy group, R3 is a hydrogen atom, a Hagn atom, and has a carbon number of 1
-8 alkyl group or C1-4 flukoxy group.

The present invention will be explained in detail below.

The 0-quinonediazide sulfonic acid ester used in the present invention is a condensation product of o-quinonediazide sulfonic acid, a polycondensation resin of the compound represented by the above general formula (1), and an aldehyde or ketone, and at least one It is a compound having an 0-quinone di7didosulfonyl group, preferably an 0-benzoquinonedi7didosulfonyl group or an 0-naphthoquinone di7didosulfonyl group.

The polycondensation resin is preferably a resin obtained by condensing the compound represented by the general formula [I] with an aldehyde or a ketone in the presence of an acidic catalyst.

Specific examples of the compound represented by the general formula [I] include:
Phenol, m-cresol, p-cresol, 2-coolphenol, 3-coolphenol, 3-ethylphenol, 3-butylphenol, 3-methoxyphenol, 4-coolphenol, 4-ethylphenol,
4-glutylphenol, 4-octylphenol, 4-
Examples include methoxyphenol, bipgal μm, 5-coolbirogatur, 5-methoxypyrogallol, 5-methylpyrogallol, 5-ethylpyrogallol, S-, methylpyrogallol, and 5-octylpyrogallol. Among these, preferred are phenol, m-cresol, p-cresol and Pigal.

In addition, examples of the aldehyde include formaldehyde, benzaldehyde, acetaldehyde,
Examples include furfural. Among these, formaldehyde is preferred.

Further, examples of the ketone include 7-setone, methyl ethyl ketone, etc., and 7-setone is preferred.

Specific examples of the polycondensation resin include phenol formaldehyde resin, cresol formaldehyde resin, phenol cresol formaldehyde resin,
4-Butylphenol formaldehyde resin, 4-
Octylphenol/formaldehyde resin, 4-methoxyphenol/formaldehyde resin, phenol/
Benzformaldehyde resin, cresol benzformaldehyde resin, pyrogallol 7 setone resin, 5
Examples include -methylpyrogallol/7setone resin, 5-octylpyrogallol/7setone resin, biru-N-roll benzaldehyde resin, phenol/birogallol benzaldehyde resin, and the like.

Preferred among these are cresol formaldehyde resin and pyrogallol acetone resin.

The o-quinonediazide sulfonic acid ester can be obtained by dissolving the polycondensation resin in an appropriate solvent such as dioxane, adding o-quinonediazide sulfonic acid chloride, and adding alkali carbonate dropwise to the equivalence point. Further, the condensation rate of o-quinonediazide sulfonic acid with respect to the OH group of the phenol of the esterified product (% relative to one OH group) is preferably 20 to 80%, more preferably 25 to 70%. , more preferably 30 to 60%.

The o-quinonediazide sulfonic acid ester of the present invention has a weight average molecular weight of 5.00 x 102 to 4.00 x 1
03 range, preferably ? , 00 x 102~
3. The range is QQ x 103. The number average molecular weight is preferably in the range of 3.00 x 102 to zoo x 103, more preferably 4.00 x
It is in the range of 102 to 1.50 x 103.

When the weight average molecular weight is less than 5.00 x 102, the durability against ÷ + processing chemicals used during printing is outstanding!
In addition, the weight average molecular weight is 4.00 x 103
When the value exceeds 1, the sensitivity and point reduction effect are significantly reduced.

Number average molecular weight and weight average molecular weight of the esterified product
The determination is carried out by GPC (gel permeation chromatography). The number average molecular weight Mn%The weight average molecular weight Mw is calculated by smoothing the peaks in the oligomer region (the peaks of the peaks are and the center of the valley).

The content of the esterified product in the photosensitive layer is preferably 5 to 60% by weight, particularly preferably 10 to 50% by weight, based on the total solid content of the photosensitive layer.

The photosensitive composition layer constituting the photosensitive layer of the photosensitive lithographic printing plate of the present invention may contain an alkali-soluble resin as a binder in order to improve film strength, processing chemical resistance, and alkali solubility. Novolak resin is usually used as the alkali-soluble resin.

The novolac resin is obtained by copolycondensing at least one selected from phenol, m-cresol (or 0-cresol), and p-cresol with an aldehyde in the presence of an acidic catalyst. Examples of the aldehyde include formaldehyde. , acetaldehyde, penzflutehyde,
Examples include aliphatic and aromatic aldehydes such as p-rein and furfural. Among these, formaldehyde is preferred.

Specific examples of novolak resins include phenol/formaldehyde resin, m-cresol/formaldehyde resin, 0-cresol/formaldehyde resin, phenol/cresol/formaldehyde copolycondensate resin, and m-cresol/formaldehyde resin.
-Cresol/p-cresol/formaldehyde copolycondensate resin, 0-cresol/p-cresol/formaldehyde copolymer resin, JP-A-55-5784
Phenol/m-cresol/p-cresol/formaldehyde copolycondensate resin described in Publication No. 1,
Examples include phenol 1o-cresol jp-cresol/formaldehyde copolycondensate resin.

In addition, a polycondensation resin of polyhydroxyfer/aldehyde can also be used. For example, JP-A-57
Resorcinol-formaldehyde resin, resorcinol-benzaldehyde resin, pilgalur-benzaldehyde resin described in JP-A-101833 and JP-A-57-101834, catechol-ho/L- as described in JP-A-59-86046. A Furtecht tree M
1, hydroquinone/formaldehye F: resin, etc.

Among the above novolak resins, phenol/m-cresol/p-cresol/formaldehyde resins are preferred.

The content of the alkali-soluble resin in the photosensitive layer is
The amount is preferably 30 to 95% by weight, more preferably 50 to 85% by weight based on the total solid content of the photosensitive layer.

The molecular weight of the alkali-soluble resin is preferably such that the number average molecular weight is 3.00 x 102 to 5.00 x 10
3, weight average molecular weight is 1.00 x 103-Zo
o X 104, better *shi<)! Mn is 1.00
X 102~3.00 X 10B, Mw is 6.0
0 x 103 to 1.50 x 104. The molecular weight of the resin was measured as described above. - Proceed in the same manner as for quinone di7dide sulfonic acid ester.

In addition to the materials described above, the photosensitive layer of the present invention can also contain other additives as necessary. Various low-molecular compounds such as phthalate esters, triphenyl phosphates, maleate esters can be used as plasticizers, and surfactants such as fluorine surfactants, ethyl cellulose-suborifulkylene ether, etc. can be used as coating properties improvers. Typical examples include nonionic activators, printout materials for forming visible images upon exposure to light, and the like.

The print material consists of a compound that generates acid or free radicals upon exposure to light, and an organic dye that changes its color tone by interacting with it.As a compound that generates acid or free radicals upon exposure to light, For example, 0-naphthoquinonediazide-4-sulfo/acid halognide described in JP-A-50-36209, JP-A-50-36209.
Trihameromethyl-2-pyrone and trihameromethyl-tri7dine described in Publication No. 3-36223, %
0-S7 described in IJ Publication No. 55-6244
Hameromethyl-vinyl-oxadi-7zole, an ester compound of toquinone diazido-4-sulfonic acid coolide and phenol or 7-niline having an electron-withdrawing substituent, described in JP-A-55-77742 Examples include compounds and diazonium salts.

In addition, examples of the organic dye include Victoria Pure Glue BOH [Hodogaya Chemical Co., Ltd.], Oil Blue≠60
3 (Orient Chemical), Patent Pure 7-Plue [manufactured by Sumitomo Mikuni Chemical], Crystal Violet, Zuriri 7-T Green, Ethyl Bioleft, Methyl Green, Erythrosin B, Paysic Fukushi Malachite Green, Oil Red, m-Cresol Purple, Triphenylmethane type, diphenylmethane type, oxazine type, xanthine type, represented by rhodamine B1 auramine, 4-p-diethyl 7minophenyliminona 7toquinone, Schifno p-diethyl 7minophenyl 7ceto7nilide, etc.
Garbage/naphthoquinone-based, 7zomethine-based, or 7-anthraquinone-based dyes may be mentioned.

Furthermore, in order to improve oil sensitivity, a photosensitive resin obtained by condensing lipophilic phenol formaldehyde resin and p-substituted phenol formaldehyde resin with sulfonic acid chloride of 0-quinonediazide can be added. These oil sensitizers account for 0.1 to 2 of the total composition of the photosensitive layer.
Preferably, the content is % by weight.

Further, a sensitizer for improving sensitivity can also be added to the photosensitive composition of the photosensitive layer of the present invention.

As a sensitizer, Q! f Gallic acid derivatives described in JP-A-57-118237, JP-A-52-800
5-membered cyclic acid anhydride as described in Publication No. 22,
For example, phthalic anhydride, tetrahydrophthalic anhydride.

Hexahydrophthalic anhydride, maleic anhydride, succinic anhydride, pyromellitic acid, itafonic acid, etc., and JP-A-58
Examples include 6-membered cyclic acid anhydrides such as those described in Japanese Patent No. 11932, such as glutaric anhydride and its derivatives. Among these, preferred are cyclic acid anhydrides,
Particularly preferred are 6-membered cyclic acid anhydrides.

In the photosensitive lithographic printing plate of the present invention, the photosensitive composition constituting the photosensitive layer can be mixed with various solvents such as methyl selon rub, ethyl selon lub, methyl selon lubricant, methyl selon lubricant, ethyl heptochloride, etc.
Cepunlubs such as nlupu acetate, dimethylform 7
Mido, dimethyl sulfoxide, dioxane, 7setone,
It can be formed by dissolving it in cyclohexanone, trichloroethylene, methyl ethyl ketone, etc. and a mixed solvent of two or more of the above to prepare a photosensitive coating solution, and coating this on the surface of the anodic oxide film side of the support of the present invention and drying it. .

In the present invention, an anodized aluminum material is used as a base material for the support, but in addition to pure aluminum, alloys containing aluminum as a main component, such as silicon, magnesium, iron, steel, zinc, etc. , aluminum alloys containing manganese, chromium, bismuth, nickel, etc.

As the aluminum material used in the present invention, rolling method,
A plate-shaped (including foil-shaped) aluminum material manufactured by hot-dip aluminum plating or the like can be used. Aluminum materials manufactured by hot-dip aluminum plating are
A metal plate such as a steel plate is plated in a molten fluminic bath and has an aluminum layer preferably having a thickness of 7 μm or more.

Surface roughness pull file B of the above base material in the present invention
is defined by the M-system shown in German standard DIN 4768 when surface roughness is measured with a stylus type surface roughness needle, and is based on the difference between the traced P file and the center line. A curve expressed as a line. In addition, the peak count (81182) in the invention is the number of peaks per inch that exceed the cutting line set parallel to the center line in the roughness profile R, and Sl is centered at 5 as shown in FIG. The number of peaks that exceed cutting line 2 above line 1 (the number of peak marks in Figure 1) is s 82
is the number of peaks that exceed cutting line 3 below the center line (first
The number of marks in the figure).

Furthermore, the burry count T1 in the invention is defined as the upper cut m2 in the roughness profile R as shown in FIG.
Beyond that, the next valley part is the lower cut IIi!
T2 is the number per inch of peaks exceeding 3 (the tens number in the second factor, and Barry Callan)
As shown in the figure, 5 is the number of peaks (the number of 0 marks in Figure 3) in the roughness profile R that exceeds the upper cutting line 2 and the subsequent valley exceeds the center line. .

In addition, the upper cutting line and the lower cutting line are installed symmetrically with respect to the center line in both the peak count and the burry count, and the distance from each center line is the cutting depth C). be. In the present invention, this cutting depth C) is 2.0 μm.0 The peak count (Sl, S
2) and the number (T1#T2) is 30<
S2<400;Sl+TtyT2<30,
Preferably, 40<Sz<300; 8
l+Ts TT2<20, more preferably 50
< 82 < Zoo. Furthermore, 40≦82/81 is preferable, and S2Δ1. S2/T2≧5 is preferred. Most preferred is 51=Tt=T2=O.

When S2≦30, the adhesion between the photosensitive layer and the support is poor, and the chemical resistance and printing durability are poor. 400≦82 s 51
When eTl and T2≧30, the point reduction effect decreases.

When measuring the above-mentioned peak count and burry count, measurements are taken at 10 different locations on the sample surface, and the average value is taken as the measured value. Also, this measurement is performed in a direction perpendicular to the direction in which the plate is stretched. The measurement length is preferably about 4.0 mark.

Furthermore, the centerline average roughness a) of the surface of the substrate used in the present invention is preferably 0.1 to 3 μm, more preferably 0.3 to 2 μm, and particularly 0.6 to 0.9 μm.
The most preferable case is from the viewpoint of water retention. Here, the center line average roughness (Ra) is the arithmetic mean of the absolute values of the distances from the center line to each point on the roughness profile as shown in the German standard DIN 4768, The horizontal center line is the X axis, the vertical direction is the Y axis,
When a point on the roughness profile is expressed as (x, y),
The Ra value obtained by the following formula for the measurement length Am is μm
It is expressed in units.

(Formula) The values of the peak count (8L182), sbury count (T11T2), and center line average roughness (Ra) can be measured using, for example, Perthometer 85P manufactured by Perthen.

Next, methods for forming the surface shape of the base material in the present invention include, for example, a mechanical method and an electrolytic etching method. Mechanical methods include, for example, ball polishing, brush polishing, liquid honing,
Examples include a puff polishing method. Among these, the method of etching by electrolysis is preferred. Abrasives used in mechanical polishing include alumina, silicon carbide, chromium oxide, red iron, tungsten carbide,
Pawn carbide, diamond, sand, silica, granite, limestone, artificial emery, steel ball, iron piece, 7 random,
Examples include bumiston, magnesium oxide, and the like. Examples of the electrolytic etching method include etching using a solution containing phosphoric acid, sulfuric acid, perchloric acid, hydrochloric acid, nitric acid, biphosphoric acid, heptanoic acid, and the like. In producing roughened aluminum lattice, the various methods described above can be used alone or in combination depending on the composition of the aluminum material.

Electrolytic etching is carried out in a bath containing the above-mentioned inorganic acids alone or in a mixture for 2 seconds or more. Among these, preferred are sulfuric acid, phosphoric acid, hydrochloric acid, nitric acid, or a mixture of two or more of these, and particularly preferred is a bath containing nitric acid or hydrochloric acid as a main component. In addition, organic acids such as furfur, acetic anhydride, and unsaturated carboxylic acids, inorganic substances such as potassium chloride, and hydrogen peroxide, colloids such as gelatin and starch, glycerin, and other viscous products, and surfactants can be added to the bath as additives. These additives may be used alone or in combination of two or more. The electrolytic etching bath is prepared by adding the above-mentioned acids and, if necessary, the above-mentioned additives to water.

The bath temperature during electrolytic etching is preferably in the range of 10°C to 50°C, and the current density is preferably in the range of 10 to 200 A/drrl. When performing electrolytic etching, it is possible to remove grease, rust, dirt, etc. from the surface of the aluminum material by degreasing and cleaning. For degreasing, use petroleum-based solvents, trichlorethylene, perchlorethylene, etc. Solvent degreasing uses chlorinated hydrocarbons to remove stains, emulsion degreasing uses a solution made by emulsifying a nonionic surfactant, a solvent such as trichlorethylene or kelsin, and water, and boiling with a treatment solution containing alkaline chemicals. Examples include alkaline degreasing and electrolytic degreasing.

Alkaline chemicals used for alkaline degreasing include sodium hydroxide, sodium carbonate, sodium silicate,
Examples include sodium phosphate, and surfactants can also be added.

After graining, if necessary, desmutting is performed using an aqueous alkali or acid solution to neutralize the material, followed by washing with water.

The aluminum material used in the present invention is then subjected to anodization treatment. When electrolysis is carried out using sulfuric acid, chromic acid, citric acid, phosphoric acid, malonic acid, etc., or a mixture of two or more of these as the electrolyte, and aluminum is used as an anode, an anodic oxide film is formed on the aluminum surface. is formed. Suitable electrolytic conditions are an acid concentration of 5 to 85% by weight, a current density of 1 to 60 A/dm', and a bath temperature of θ to 80°C. For example, in a 1% sulfuric acid aqueous solution of 10 to 2011 J, the bath temperature is 10 to 30°C, the voltage is 15 to 20 V, and the current density is [1 to 2 A/dm'.

Conditions for time 2 to 10 minutes and concentration 1 to 30% by weight
in a phosphoric acid aqueous solution, bath @20~70℃, voltage 20~S
OV, current density [1-2 klrid, time 0.5-10
Examples include a method in which the test is carried out under conditions of minutes. The surface of the anodic oxide film thus formed is suitably 5 to 70 η/da', preferably 15 to 50 η/dry? It is more preferably in the range of 25 to 40 Q/di. The amount of anodized film can be determined by, for example, dipping an aluminum plate in a phosphoric acid term acid solution (85% phosphoric acid solution 35W11.Chromium oxide (Vl) 2 (prepared by dissolving 11L in water) and dissolving the oxide film. , which can be determined by measuring changes in weight before and after dissolving the film on the plate.

In the present invention, "using an anodized aluminum material as a base material" means an anodized film surface of an aluminum material (the film surface has a specific surface shape of the base material of the present invention).
It means that a photosensitive layer is provided on the surface of the printing plate, and the anodized film includes those obtained by subjecting the film surface to a surface treatment. For example, in the present invention, an anodized aluminum material may be used as a support so that a photosensitive layer is coated on the anodized film surface, or an anodized aluminum material may be used as a support so that a photosensitive layer is coated on the anodized film surface of the anodized aluminum material. As a support, the surface treatment is applied to
The support may be used so that a photosensitive layer is provided on the surface treated, or an anodized aluminum material subjected to a treatment such as lining may be used as the support. This surface treatment includes, for example, pore sealing treatment, undercoating with an aqueous solution of a water-soluble polymer compound and a water-soluble salt, etc., performed on the anodized surface. Examples of the sealing treatment include boiling water treatment, steam treatment, sodium silicate treatment, and bitermate solution treatment. The sealing treatment is performed immediately after the anodizing treatment.

If the roughened aluminum material is as thin as foil,
A metal plate, plastic film, paper, etc. may be attached to the back surface directly or via an adhesive layer.

The above-mentioned water-soluble polymer compound preferably has a solubility of 0.01% or more. Preferred water-soluble polymer compounds include natural polymer compounds such as gum arabic, starch, textrin, sodium alginate, and gelatin, water-soluble cellulose compounds, such as water-soluble salts of carboxyfurkyl cellulose (as furkyl) (methyl, ethyl, propyl, etc.), furkylcellulose,
For example, methylcellulose, hydroxymethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, polyacrylic acid or a water-soluble salt thereof, polymethacrylic acid or a water-soluble salt thereof, acrylic acid copolymer or a water-soluble salt thereof, Synthetic polymer compounds such as methacrylic acid copolymer or its water-soluble salt, styrene/maleic anhydride copolymer, polyvinylfurfur, polyacrylamide, polyvinylpyrrolidone, etc., and examples of the water-soluble salt of the polymer compound include sodium salt, Examples include potassium salts. The above six water-soluble polymer compounds may be used alone or in combination of two or more. Among the water-soluble polymer compounds, natural polymer compounds such as starch and dextrin, and water-soluble cellulose compounds are preferred. Also, the molecular weight is 500~
1,000,000 is preferably used.

Water-soluble salts used with water-soluble polymer compounds are preferably those having a solubility of 0.01% or more, particularly inorganic or organic acids such as calcium, magnesium, zinc, barium, strontium, fupartite, manganese, and nickel. and silicon salts. Representative organic acid salts are salts of carboxylic acids such as acetic acid, propionic acid, butyric acid, succinic acid, benzoic acid, salicylic acid, and the 7-cetyl-7-cetone complex salt. Representative inorganic acid salts are chloride, bromide, chlorate, bromate, iodide, iodate, nitrate, sulfate and phosphate. The water-soluble salts may be used alone or in combination of two or more.

As water-soluble salts, organic acid salts are particularly preferred, and calcium, magnesium, barium and zinc salts are particularly preferred. The coating amount of the layer containing the water-soluble polymer compound and the water-soluble salt formed by this method is preferably 0.001 to 1 q/d, and especially 0.05 to 0.5 q/l.
di is preferred. In addition to this, the surface can also be treated with an aqueous solution of fluorinated zirconate.

When using the photosensitive lithographic printing plate of the present invention, a known method is applied, in which a positive F1 film is adhered, exposed with an ultra-high pressure mercury lamp, metal halide lamp, etc., developed with an alkaline developer, and used as a printing plate. be done.

Examples of the alkaline developer include aqueous solutions of sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, potassium metasilicate, sodium diphosphate, sodium triphosphate, etc.
The concentration of the alkaline agent is preferably 0.61 to 10% by weight.

The present invention will be explained below with reference to examples, but the present invention is not limited thereto.

Example 1 Aluminum plate with a thickness of 0.24 mm (material: 1050 mm)
1 Trade H16) was degreased for 1 minute at 60"Q in a 5% aqueous solution of caustic soda, neutralized by immersing it in 30% sulfuric acid at 25°C for 4 seconds, and then washed with water. In a 5 molar aqueous hydrochloric acid solution, temperature = 25°C, current density = 55 A/
Electrolytic etching treatment was performed under the conditions of dm' and treatment time = 35 seconds. Then, in a 5% aqueous solution of caustic soda,
℃, after 10 seconds of Tesmut treatment, in sulfuric acid solution temperature = 40℃, voltage: 20V, current density 23A
/da', time: anodizing treatment was performed for 9 minutes. In order to measure the amount of anodic oxide film, the anodic oxide film was dissolved and removed by immersion in a phosphoric acid solution (35 ju of 85% phosphoric acid solution and 20 g of chromium oxide (Vl) dissolved in 111 C of water). When I calculated the difference in weight of the board before and after koshira, it was 24Q.
/dm.

Next, the anodized aluminum plate was immersed in a 90'Q hot water solution for 5 minutes to seal the holes.

Next, the surface roughness of this support was measured. The surface roughness was measured using a Perthometer 85P manufactured by Perthen under the following measurement conditions.

Needle cartridge: RT-500 (diamond needle, needle tip radius 5 μm) Needle sensitivity adjustment: Pen-10-1, adjusted based on 90 μm Profile: Roughness profile R Vertical magnification: 25 μm horizontal magnification
Rate: 250 μm Cutting depth C: ZO μm Measurement length: 4.0 mm Cutoff value: 0.8 wx The values of the peak count, burry count, and center line average roughness of the obtained aluminum support are as follows: It is.

Peak count 52 = 194 # 51 = 0 Burry count T2 = 0 # T1 = 0 Center line average roughness Ra = 0.70 μm The above value is the average value of the measured values at 10 different locations, and the measurement was performed in the direction of plate extension and It was done at right angles. Note that the surface reflectance of the support was 47%. The reflectance was measured using MgO as a reference using a 200-20 type double beam spectrophotometer manufactured by Hitachi, Ltd. and its integrating sphere attachment.
The measurement was carried out in 1.

Next, a photosensitive coating solution having the following composition was applied to the aluminum support (1) using a rotary coating machine, and the temperature was heated at 100°C.
The plate was dried for 4 minutes to obtain a photosensitive planographic printing plate (A).

(Photosensitive coating liquid composition) 0 Naphthoquinone-(1,2)-diazide-(2)-5-
Esterified product of sulfonic acid chloride and m-cresol/formaldehyde novolac resin (condensation rate 25 mol%, number average molecular weight Mn = 1200, weight average molecular weight Mw = 1800) 1910 phenol/m-cresol/p-cresol/formaldehyde copolymer Condensation resins (phenol, m-cresol and p-
The molar ratio of each cresol is 39:38:23, number average molecular weight Mn = 1400, weight average molecular weight Mw = 920
0) 5.3 JilO Oil Pruner 603 (manufactured by Oriental Co., Ltd.) o, os 11 0 Ethyl Sepenlup 100d The coating weight after drying was about 22 mf/drtt.

The molecular weights of the esterified product of the 0-quinonediazide compound and m-cresol novolak resin and the ternary copolycondensation resin as the binder were measured using GPC (Kölperminex chromatography). GPC
'lt+ constant conditions are as follows.

Equipment: Model 635 manufactured by Futachi, Separation column: Showa Denko (
5hodex A 802, A303 and A 8 manufactured by Co., Ltd.
04 were connected in series, temperature: room temperature, solvent: tetrahydrofuran, flow rate: 1.5a#/min, and a calibration curve was prepared using polystyrene as a standard.

A step tablet for sensitivity measurement (manufactured by Eastman Hudak Company/1) was placed on the thus obtained photosensitive lithographic printing plate.
62, 21-step gray scale with a density difference of 0 and 15), and a halftone dot scale of 150 lines/inch (Sakura Step Tablet Type Tps-B manufactured by Konishiroku Photo Industry Co., Ltd.). Using a 2 Kw metal halide lamp (IDOLFI Y2000, manufactured by Iwasaki Electric Co., Ltd.) as a light source, under the condition of 8.0 mW/cd, 35
Samples were prepared that were exposed to light for 2 seconds, 50 seconds, 70 seconds, and 100 seconds. Next, these four samples were developed with a 4% potassium metasilicate aqueous solution at 25° C. for 45 seconds, and the non-image areas were completely removed to obtain a lithographic printing plate. This is 49% of the original area on the lithographic printing plate after applying developing ink.
We measured the reproducibility of the halftone dot area and examined the dot reduction effect.

The size of the dot loss is determined by the area ratio of each halftone dot obtained by the above 35, 50, 70 and 100 second exposure using a halftone dot analyzer (Sakura Area Duck-1000, manufactured by Konishiroku Photo Industry Co., Ltd.). The difference in area ratio between the original halftone dots and the halftone dots on the lithographic printing plate is determined by comparing with the original halftone dots measured in the same way, and from this K, the size of the reduction in halftone dots relative to the original is expressed. did. In this way, the relationship between exposure time and point loss % is determined, and from this relationship, if point loss 10% is used as a standard, this is Kl! The exposure time was 88 seconds.

The shorter the exposure time, the greater the halftone dot reduction effect.

Furthermore, when the sensitivity at an exposure time of 70 seconds was measured using the gray scale of the step tablet, it was 3! The first stage was completely developed (clear).

Furthermore, in order to examine processing chemical resistance, we used Ultra Plate Cleaner (A), which is used as a cleaning liquid to remove background stains that occur in non-image areas during printing.

The durability against B and C (manufactured by Chemical Co., Ltd.) was examined.

After immersing the printing plate obtained by the 70-second exposure, on which an image with density differences on gray scale steps was formed, in Ultra Plate Cleaner stock solution at room temperature for 20 minutes,
By washing with water and comparing with the image area before immersion, the degree of attack of the image area against the treatment chemicals was determined. As a result, the printing plate had no erosion in the image area, and the halftone dots were preserved up to the halftone dots with an area ratio of 3%, showing good resistance to processing chemicals.

Comparative Example 1 Aluminum plate with a thickness of 0.24 m (material:
y4jtH16) at the bottom of the polishing machine box, place a steel ball (10-20m in diameter) on top of it, and add silica sand (100m
~250 mesh) and a small amount of water were mixed with this and the plate was eccentrically rotated horizontally. After washing with water, it was subjected to alkaline etching in a 10% caustic soda aqueous solution, then neutralized with 30% sulfuric acid, washed with water and dried. Furthermore, in a sulfuric acid solution, the temperature f: 40
C., voltage: 20 V, current density: 3 A/d, l, time: 9 minutes. Example 1: Anodic oxide film amount
When measured in the same manner as above, 24 erg/dy
Met. Next, the anodized aluminum plate was
It was immersed in a hot water solution at 0° C. for 5 minutes to seal the holes.

When the surface roughness of the support was measured in the same manner as in Example 1, the following results were obtained.

Peak count 82=216 S1=137 Barry count T2”130 tr T1=86 Center line average roughness Ra = 0.67 μm or more, Sz 1T21T1 > 30, and the surface shape is different from that of the support of the present invention. have.

Next, the surface reflectance of the support was measured in the same manner as in Example 1, and was found to be 48%.

Thus obtained aluminum plate [■] - Example 1 on top
The same photosensitive coating solution as above was applied and dried in the same manner to obtain a photosensitive lithographic printing plate [F]).

The coating weight after drying is approximately 2289/dy? Met.

Next, using this photosensitive lithographic printing plate (B), as in Example 1, K, dot reduction effect, sensitivity measurement based on the number of gray scale clear steps, and processing chemical resistance were examined. Table 1 shows the results.
1C is shown.

Comparative Example 2 Aluminum plate [I]K of the support produced in Example 1,
The following photosensitive coating liquid was applied and dried in the same manner as in Example 1 to obtain a photosensitive lithographic printing plate (C).

(Photosensitive coating liquid composition) 0s7toquinone-(1,2)-diazide-(21-5-
Esterified product of sulfonic acid chloride F and resorcinol-benzaldehyde resin (4! Synthesized by the same method as in 1982-1044, Example 1, condensation rate 25
Mol%, number average molecular weight Mn = 1500, weight average 'molecular weight Mw = 1600) 16 Iiophenol/m-cresol/p-cresol/formaldehyde copolycondensation resin (7 ethanol, m-cresol and p-cresol)
The molar ratio of each cresol is 39:38:23
, number average molecular weight Mn = 1400, weight average molecular weight -J
I Mw = 9200 ) 5.610
Oil Blue 4P603 (manufactured by Oriental Co., Ltd.) 0
．． 08.9 0 Methyl Sep Solp 100111
The coating weight after drying was approximately 22 η/dm''.

As mentioned above, the photosensitive lithographic printing plate of Example 1 and the photosensitive lithographic printing plate (C) of Comparative Example 2 differ only in the 0-naphthoquinonediazide sulfonic acid ester used, and other materials and The supports are the same. The total number of moles of 0-naphthoquinonediazide sulfone residues in both photosensitive layers is the same.

Next, using this photosensitive lithographic printing plate (C), the dot reduction effect, sensitivity, and processing chemical resistance were examined in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 3 On the aluminum support [■] prepared in Comparative Example 1, gallic acid (JP-A-57-118) was added to the photosensitive coating solution of Example 1.
described in Example 1 of Publication No. 237).
A photosensitive coating liquid containing No. 241 was applied and dried in the same manner as in Example 1 to obtain a photosensitive lithographic printing plate.

The coating weight after drying was approximately 2211 g/d7@. Next, using this photosensitive lithographic printing plate (D), the dot reduction effect was obtained in the same manner as in Example 1. G& and treatment chemical resistance were investigated.

The results are shown in Table 1.

Comparative Example 4 The aluminum support (II) prepared in Comparative Example 1 was anodized under the following conditions: bath: 15% sulfuric acid solution, temperature: 40°C, voltage: 10V, current density: 2A/dm.
An aluminum support [■] was obtained in the same manner as in Comparative Example 1 except that the time was changed to 5 minutes. When the amount of this anodic oxide film was measured in the same manner as in Example 1, it was 50 y/d.
, l.

Next, the anodized aluminum plate was immersed in a hot water solution at 90° C. for 5 minutes to seal the holes.

The surface roughness of the aluminum support (III) was measured in the same manner as in Example 1, and the following results were obtained.

Peak count M = 210 81 = 140 Barry Cuff 7) T2 = 138 Barry count TI = 84 Center line average roughness Ra = 0.66 μm or more, almost different from the surface roughness of the aluminum support (IT) of Comparative Example 1 There was no. In addition, the surface reflectance was measured in Example 1.
When measured in the same manner as above, it was 50%.

The same photosensitive coating solution as in Example 1 was applied to the thus obtained aluminum support [■] and dried in the same manner to obtain a photosensitive lithographic printing plate @).

The coating weight after drying was approximately 2211 g/d-.

Next, using this photosensitive lithographic printing (Iida), the dot reduction effect, sensitivity, and processing chemical resistance were examined in the same manner as in Example 1.

The results are shown in Table 1.

Comparative Example 5 Aluminum plate with a thickness of 0.24 m (material 1050,
Tempering H16) K was grained with a rotating nylon brush in a suspension of pumice stone and water, and after washing with water,
Alkaline etching was performed in a 10% caustic soda aqueous solution.

After washing with water, the surface was washed and neutralized by immersing it in a 30% nitric acid aqueous solution for 1 minute at room temperature. Thereafter, alternating current electrolysis was carried out at a current density of 20 persons/drl in an electrolytic bath containing 0.1 mol/l of salt dispersion. Next, after desmutting in a 5% caustic soda aqueous solution at 60°C for 10 seconds, in a sulfuric acid solution at a temperature of 40°C.
C., voltage: 20 V, current density: 3 A/d/, time: 9 minutes. Example 1: Anodic oxide film amount
When measured in the same manner as above, 24 wi/dvpl
Met. Next, the anodized aluminum plate was
It was immersed in a hot water solution at 0° C. for 5 minutes to seal the holes.

When the surface roughness of the support was measured in the same manner as in Example 1, the following results were obtained.

Peak count 82 = 197 # 81 = 83 1 count T2 = 87 z T1 = 41 Center line average roughness A = 0.70 μm or more 5 K 81. T2. TI > 30,
It has a different surface shape from the support of the present invention.

Next, the surface reflectance of the support was measured in the same manner as in Example 1, and was found to be 65%.

On the thus obtained aluminum plate [■], the same photosensitive coating solution as in Example 1 was applied and dried in the same manner to obtain a photosensitive lithographic printing plate (F).The coating weight after drying was approximately 22■/ Using this photosensitive lithographic printing plate (F) of 0 order which was dd, the dot reduction effect, sensitivity and treatment chemical resistance were examined in the same manner as in Example 1. The results are shown in Table 1.

Table 1 summarizes the results of the study of point reduction effect, sensitivity, and treatment chemical resistance conducted for Example 1 and Comparative Examples 1 to 5.

Margin below In the treatment chemical resistance in Table 1, "A" shows almost no erosion in the image area (・.

"B" shows slight erosion of the above. "C" shows significant erosion of the same as above, and the grains of the support below the photosensitive layer are completely exposed.

It means that.

As is clear from Comparative Example 1, when a support with a surface shape different from that of the support of the present invention is used, the point reduction effect is significantly reduced and the clear sensitivity is also reduced. When the support of the present invention is used, and even if the weight average molecular weight of the 0-quinonediazide sulfonic acid ester used is 4.00 x 103 or less, the composition differs from that of the present invention. It can be seen that the point reduction effect is reduced.Furthermore, as can be seen from Comparative Example 3, if gallic acid is added to the photosensitive layer, the point reduction effect can be enhanced to some extent even if a support other than the one of the present invention is used. However, in return, the treatment chemical resistance was significantly reduced.Also, from Comparative Example 4,
It can be seen that if the support is different from that of the present invention, even if the amount of anodic oxide film is increased, the point reduction effect does not reach the present invention, and on the contrary, the clear sensitivity decreases.

Furthermore, as is clear from Comparative Example 5, if the support is different from that of the present invention, even if the surface reflectance is increased, the dot reduction effect and sensitivity will not be as good as those of Example 1 of the present invention.

Example 2 A 0.24 m thick full minilam board (material 1050, tempered H16) K was subjected to surface roughening treatment with a rotating nylon brush using an abrasive and water suspension, and after washing with water,
% caustic soda aqueous solution. After washing with water, it was immersed in a 20% nitric acid aqueous solution at room temperature to perform desmutting. Next, in a sulfuric acid solution, temperature: 40°C, voltage: 20 V, current density: 3 A/dm', time: 9
Anodized in minutes.

The amount of anodic oxide film was measured in the same manner as in Example 1 and was found to be 24 my/drl. Next, the anodized Fluminilam board was immersed in a hot water solution at 90° C. for 5 minutes to seal the holes.

When the surface roughness of the support was measured in the same manner as in Example 1, the following results were obtained.

Peak count 82 = 110 Peak count 5r = 8 Barry count T2 = 8 1 Tr = 8 Center line average roughness Ra = 0.65 μm A photosensitive coating liquid with the following composition was applied on the aluminum support (V) thus obtained. It was coated using a spin coater and dried at 100° C. for 4 minutes to obtain a photosensitive planographic printing plate (Gl).

(Photosensitive coating liquid composition) 0 Naphthoquinone-(1,2)-diazide-(21-5-
Esterified product of sulfonic acid koolide and pyrogallol φ7 seven ton resin (number average molecular weight Mn" 1500, weight average molecular weight MW = 1800°, condensation rate 50 mol%)
1.7 NO Phenol'
m-cresol/p-cresol/formaldehyde copolycondensation resin (the molar ratio of phenol, m-cresol, and p-cresol is 40:36:24, number average molecular weight Mn = 1400, weight average molecular weight Mw = 92
00 ) 6.5110 Victoria Vinifoop Blue BOHO, 151 (manufactured by Odougaya Kagaku Co., Ltd.) 0 Methylselon Lupe The coating weight after drying for 100 d was approximately 2211 i+/dm.

Next, using this photosensitive lithographic printing plate (Gl), K, dot reduction effect, sensitivity, and processing chemical resistance were examined in the same manner as in Example 1.

As a result, the sensitivity was 1 step clear 3 on the step tablet gray scale, the exposure time required for 10% point reduction was 95 seconds, and the processing chemical resistance was good with no erosion observed in the image area, as mentioned above. It was a person in the evaluation rank of clothes IK.

Comparative Example 6 A photosensitive coating liquid having the same composition as that of Example 2 was prepared except that naphthoquinonediazide sulfonic acid ester therein was replaced with the following.

0 Naphthoquinone-(1,2)-Diazil''-(2)-
Esterified product of 5-sulfonic acid p-ride and pyrogallol/7cetone resin (number average molecular weight Mn = 2670,
Weight average molecular weight Mw = 4800, condensation rate 50 mol%
) 1.71i The above newly prepared photosensitive coating solution was similarly coated on the aluminum support (V) prepared in Example 2 and dried to obtain a photosensitive lithographic printing plate circle.

The coating weight after drying was approximately 22 q/di.

The difference between the photosensitive lithographic printing plate [Gl of Example 2] and the photosensitive lithographic printing plate circle of Comparative Example 6 is that the naphthoquinonediazide sulfonic acid esters used are the same in type but have different molecular weights. The photosensitive lithographic printing plate (2) is outside the scope of the present invention.

Next, using this photosensitive lithographic printing plate B), the one-point reduction effect, sensitivity, and processing chemical resistance were examined in the same manner as in Example 1.

As a result, the sensitivity was 1 step clear 2 on the step tablet gray scale, the exposure time required for a 10% point reduction was 120 seconds, and the processing chemical resistance was A in the evaluation rank.

From the above results, the naphtho-? Even if the type of di7didosulfonic acid ester is the same as that of the present invention,
It can be seen that when the weight average molecular weight exceeds 4.00 x 1G3, the dot reduction effect and sensitivity of a photosensitive lithographic printing plate using it are significantly reduced.

(Effects of the Invention) The photosensitive lithographic printing plate of the present invention has a photosensitive layer to which an o-quinonediazide sulfonic acid ester having a specific composition and molecular weight is added, and a surface shape characterized by a peak count and Barry Callan) K. By combining the aluminum support, it has a remarkable dot reduction effect and is highly sensitive. Further, there is no reduction in treatment chemical resistance.

[Brief explanation of the drawing]

Figure 1 is a graph of the roughness profile showing the peak count (81, Sz), Figure 2 is Barry Callan) (T1)
FIG. 3 is a graph of the roughness profile showing Barry Callan) (T2). 1... Center a 2... Upper cutting line 3
・・・・・・Bottom cutting line

Claims (1)

[Scope of Claims] A photosensitive lithographic printing plate comprising a photosensitive layer containing a photosensitive composition containing an o-quinonediazide compound on a support made of anodized aluminum material. The quinonediazide compound is an o-quinonediazide sulfonic acid ester of a polycondensation resin of at least one compound selected from the following general formula [I] and an aldehyde or ketone, and the weight average of the o-quinonediazide sulfonic acid ester is Molecular weight is 5.00×10^2~
4.00×10^3, and the peak count (S_1, S_2) and burry count (T_1, T_2) at a cutting depth of 20 μm of the roughness profile R of the surface of the photosensitive layer side of the base material are 30<S_2 <400, S_1,
A photosensitive lithographic printing plate characterized in that T_1, T_2<30. General formula [I] ▲ Numerical formulas, chemical formulas, tables, etc. Represents an alkoxy group having 1 to 4 carbon atoms, and R_3 represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 8 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms.)