JPS6388546A - Positive type photosensitive composition - Google Patents

Abstract

PURPOSE:To obtain the titled composition having high sensitivity and to enlarge developing latitude of the titled composition by specifying a novolak resin in the titled composition composed of a o-quinone diazido compd. and an alkaline soluble novolak resin. CONSTITUTION:In the titled composition composed of the o-quinone diazido compd. and the alkaline soluble novolak resin, 5-40wt% of the novolak resin contains <=6 of phenol nucleuses and >=75wt% a o-cresol resin. The aldehyde usable for synthesizing a dimethylol compd. is exemplified by formaldehyde or paraformaldehyde, etc. The alkali used comprises sodium hydroxide and potassium hydroxide. The used amount of the aldehyde is 1.5-3mol per 1mol of o-cresol. The used amount of the alkali is 0.1-1.2mol. The reaction temp. is preferably 30-90 deg.C. Thus, even in case of raising the sensitivity of the titled composition to 2 times of usual sensitivity, the change of sensitivity of the titled composition is remarkably small in case of changing processing time, rate of dilution of a developing solution and developing temp. etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of the Invention] The present invention relates to a positive-working photosensitive composition, and more particularly to a positive-working photosensitive composition having high sensitivity and a wide development latitude.

[Prior art]

Photosensitive compositions containing 0-quinonediazide compounds have been used industrially as excellent positive-working photosensitive compositions in the production of lithographic printing plates and as photoresists. Various proposals have been made regarding methods of increasing the sensitivity of this composition, but none have been found to be satisfactory. For example, if the amount of the O-quinonediazide compound is reduced, the sensitivity will increase, but there will be a drawback that the development latitude will become narrower. When over-developed, unexposed areas dissolve, resulting in a significant increase in sensitivity and a decrease in rigidity. The addition of a cyclic acid anhydride described in JP-A No. 52-80022 increases sensitivity and causes a relatively small decrease in development latitude, but if the amount added is increased to sufficiently increase sensitivity, development The disadvantage is that the attitude is reduced.

Gallic acid and the like described in JP-A-57-118237 also have similar drawbacks.

[Purpose of the invention]

Therefore, an object of the present invention is to provide a positive-working photosensitive composition comprising an 0-quinonediazide compound and an alkali-soluble novolac resin, which has high sensitivity and a wide development latitude.

[Structure of the Invention] As a result of repeated studies, the present inventors have found that the above object can be achieved by using an appropriate amount of a specific 7-borabuku resin. That is, the present invention provides a positive weight photosensitive II' resin composition comprising an 0-quinone diazide compound and an alkali-soluble novolac resin, in which 5 to 40% by weight of the novolac resin contains 0-
This is a positive photosensitive composition characterized by being a cresol resin.

Alkali-soluble novolak resins in conventionally used positive-working photosensitive compositions have an average number of nuclei of about 5 to 10, including from 1 to 15 nuclei, but the present inventors It has been found that a photosensitive composition with high sensitivity and a wide development latitude can be obtained by using an appropriate amount of 0-cresol containing a small amount of 7-nuclear atoms or more, that is, 75% by weight or more of 6-nuclear atoms or more. Ta.

If the content of the O-cresol resin having 7 or more nuclear bodies exceeds 25% by weight based on the total O-cresol resin, the effect of increasing sensitivity will be small. Furthermore, even if the 0-cresol resin contains 75% by weight or more of 6-nuclear bodies or less, if the amount used is 5% by weight or less of the alkali-soluble novolac resin, the effect of increasing sensitivity will be small, and -
If the strength is 40% by weight or more, the resistance to chemicals containing organic solvents and acids, such as cleaners and blanket cleaning agents, decreases.

The weight ratio of each nuclear body is calculated by cutting out the adjacent portion of each peak serum in the chart obtained by GPC and using the weight method (see Journal of the Chemical Society of Japan, 1972, Nα4, p801). G
The PC measurements were conducted under the following conditions.

Equipment: Toyo Soda Kogyo ■ (High Speed Liquid Chromatograph HLC-802UR) Column: G4000H, +G2000) 1g Solvent: Diluted tetrahydrofuran Flow rate + 1.5 me/m 1n6 nuclear bodies and below are 75 times heavier! % or more of 0-cresol/borac resin, 0-cresol may be condensed with aldehydes in the presence of an acidic catalyst according to a conventional method, but preferably
~ Suitably prepared by reacting an 0-cresol dinuclear dimethylol compound (hereinafter referred to as a dimethylol compound) obtained by reacting cresol and aldehydes in the presence of an alkali with Q-cresol in the presence of an acidic catalyst. Can be done.

Specific examples of aldehydes for preparing the dimethylol compound include formaldehyde, paraformaldehyde, and the like. The alkali to be used is not particularly limited, but sodium hydroxide and potassium hydroxide are preferred. The amount of aldehyde used is preferably 1.5 to 3 mol per 1 mol of 0-cresol, and the amount of alkali used is preferably 0.1 to 1.2 mol. The reaction temperature is not particularly limited, but is preferably 30 to 90°C. Examples of acid catalysts used to prepare 0-talesol novolak from dimethylol compounds include inorganic acids such as hydrochloric acid and sulfuric acid, formic acid, acetic acid, sychoic acid, p. ) Organic acids such as luenesulfonic acid can be used.

The amount of acid catalyst used is 0.1 to 0.1 to dimethylol compound.
10% by weight is preferred. The amount of 0-cresol per mol is preferably in the range of 2 to 15 mol per mol of the dimethylol compound, and the reaction temperature is preferably 40 to 12[deg.]C.

Other alkali-soluble novolak resins used in the compositions of the present invention include conventional m,p-cresol-formaldehyde resins, m-cresol-formaldehyde resins, phenol-formaldehyde resins, p-cresol-phenol-formaldehyde resins, etc. These usually have 15 nuclei, and the proportion of 7 or more nuclei exceeds 40% by weight.

The composition of the present invention may contain alkali-soluble resins other than the above-mentioned alkali-soluble novolak resins, if necessary. For example, styrene-acrylic acid copolymer, methyl methacrylate-methacrylic acid copolymer,
Examples include alkali-soluble polyurethane resin and alkali-soluble polybutyral resin. Such alkali-soluble resin can be added up to 100% by weight, preferably up to 50% by weight, based on the alkali-soluble novolac resin. .

Particularly preferred 0-quinonediazide compounds for use in the present invention are 0-naphthoquinonediazide compounds, such as U.S. Pat.
No. 11, No. 3.046.121, No. 3.046.
No. 115, No. 3.046.118, No. 3. (1
No. 46,139, No. 3, No. 046.120, No. 3.
No. 046.121, No. 3.046.122, No. 3
．． 046.123, 3.061.430, 3.102.809, 3.106.465, 3.635.709, 3.647.443 It is described in numerous publications including the specifications of , and these can be suitably used. Among these,
In particular, 0-naphthoquinonediazide sulfonic acid esters or 0-naphthoquinonediazidecarboxylic acid esters of aromatic hydroxy compounds, and O-
Naphthoquinonediazide sulfonic acid amide or O-naphthoquinonediazidecarboxylic acid amide is preferred, especially the ester of O-naphthoquinonediazide sulfonic acid to the condensate of pyrogallol and acetone as described in U.S. Pat. No. 3,635,709. A product obtained by subjecting a polyester having a hydroxy group at the end to an ester reaction with 0-naphthoquinonediazide sulfonic acid or 0-naphthoquinonediazidecarboxylic acid as described in U.S. Patent No. 4.028.111, U.S. Patent No. 4.13
0-naphthoquinonediazide sulfonic acid or Q-naphthoquinonediazidecarboxylic acid is added to a homopolymer of p-hydroxystyrene or a copolymer thereof with other copolymerizable monomers as described in No. 9.384. Ester-reacted product, U.S. Patent No. 3.759.71
A copolymer of p-aminostyrene and other copolymerizable monomers as described in Specification No. 1 is subjected to an amide reaction with 0-naphthoquinonediazide sulfonic acid or 0-naphthoquinonediazidecarboxylic acid. Excellent.

Further, as described in U.S. Pat. No. 4,123,279, in addition to the above-mentioned phenolic resins, t-butylphenol formaldehyde resins R'tt, n-octylphenol formaldehyde resins having 3 carbon atoms, etc.
A condensate of phenol or cresol substituted with an alkyl group of 8 to 8 and formaldehyde may be used in combination. The mixing ratio of the 0-quinonediazide compound to the alkali-soluble resin is suitably in the range of 50:50 to 15:85 by weight, more preferably in the range of 40:60 to 20:80.

The positive photosensitive composition according to the present invention may further contain other dyes, pigments, plasticizers, etc., if necessary. Other suitable dyes include oil-soluble dyes and basic dyes. Specifically, oil yellow #101 oil yellow #130, oil pink #312, oil green BG, oil blue BO3, oil blue #603
, Oil Black BY, Oil Black BS, Oil Black T-505 (manufactured by Orient Chemical Industry Co., Ltd.), Crystal Violet (C142555), Methyl Violet (CI 42535), Rhodamine B
(CI45170B>, malachite green (CI42
000), methylene blue (CI52015), etc.

Such dyes can be contained in an amount of 1% by weight or less based on the total weight of the positive photosensitive composition according to the present invention.

The positive photosensitive composition according to the present invention is coated on a desired support after being dissolved in a solvent that dissolves each of the above components. Solvents used here include ethylene dichloride, cyclohexanone, methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2-, methoxyethyl acetate, toluene, ethyl ester, propylene glycol monomethyl ether acetate, propylene glycol methyl ether, etc. These solvents can be used alone or in combination. And the concentration (solid content) in the above ingredients is 2 to 50% by weight? It is 6. The coating amount varies depending on the application, but for example, for photosensitive planographic printing plates, a solid content of 0.45 to 7 g/m' is generally appropriate, and more preferably a solid content of 1.5 to 3 g/m'. range.

In order to improve the visual contrast after exposure, the positive-working photosensitive composition according to the present invention may contain a compound that generates an acid that changes the color scale of the dye when exposed to light, such as the one described in the US patent. 0-naphthoquinonediazide-4-sulfonyl chloride as described in U.S. Pat. No. 3.969.118, 2-styryl-5- as described in U.S. Pat. Trihalomethyl-1,3,4 oxazole, U.S. Patent No. 3.
It is preferable to add vinyltrihalomethyl-S-triazine compounds such as those described in No. 987.037.

Further, in order to improve the coating surface quality, it is preferable to contain a fluorine-based surfactant or the like.

Still other additives include U.S. Patent No. 4.115.12
A small amount of a cyclic acid anhydride described in No. 8 may be added. When applying a positive-working photosensitive composition to a lithographic printing plate, a photosensitive liquid is applied onto a support.

As a support for such a positive-working 28 plate, any material having a hydrophilic surface can be used, and various materials conventionally usable as supports for lithographic printing plates are included, but an aluminum plate is particularly preferred. . Suitable aluminum plates include pure aluminum plates and aluminum alloy plates, as well as plastic films laminated or vapor-deposited with aluminum. The surface of the aluminum plate is preferably subjected to a surface treatment such as graining treatment, immersion treatment in an aqueous solution of sodium silicate, potassium fluorozirconate, phosphate, or the like, or anodization treatment. Also, after graining, US Patent No. 2.714.
Aluminum plate immersed in an aqueous IJ solution as described in U.S. Pat. As described in TGT, No. 461, an aluminum plate is anodized and then immersed in an aqueous solution of an alkali metal silicate.
3.461, which is anodized and then immersed in an aqueous solution of polyvinylphosphonic acid, is also preferably used. The above anodizing treatment may be performed using an inorganic acid such as phosphoric acid, chromic acid, sulfuric acid, or boric acid.
Alternatively, the method may be carried out by passing an electric current through an aluminum plate in an electrolytic solution of an organic acid such as oxalic acid or sulfamic acid or a salt thereof or a non-aqueous solution thereof alone or in combination of two or more.

Also effective is silicate electrodeposition as described in US Pat. No. 3,658,662.

Further, a support coated with electrolytic grains as disclosed in U.S. Pat. Also useful are those that have been anodized.

Also preferred are grained, chemically etched, and then anodized aluminum plates as described in U.S. Pat. No. 3,834,998.

The positive type 28 plate according to the present invention is produced by exposing the transparent original image to a light source rich in actinic rays such as a carbon arc lamp, mercury lamp, metal halide lamp, or xenon lamp in the same way as in the past, and then developing it with a developer to form a photosensitive layer. The exposed areas are removed to expose the hydrophilic surface of the support underneath and the lithographic stamp is printed. Preferred developing solutions include sodium silicate, potassium silicate, sodium hydroxide 5, potassium e-zeta oxide, lithium hydroxide, and tertiary F2.
alkaline agents such as sodium acid, dibasic sodium phosphate, potassium phosphate, dibasic potassium phosphate, dibasic ammonium phosphate, dibasic ammonium phosphate, sodium metasilicate, sodium bicarbonate, aqueous ammonia, etc., e.g. monoethanol An aqueous alkaline solution containing at least one alkali such as an organic alkaline agent such as amine, jetanolamine, etc. is used, and a particularly preferred composition of the aqueous alkaline solution is detailed in U.S. Pat. No. 4,259,434. There is. The developing method can be carried out by various means such as an automatic developing machine having both a developing and gum section, a normal automatic developing machine having a water washing section, dish development, and manual development.

The photosensitive lithographic printing plate using the positive-working photosensitive composition containing the 0-cresol resin of the present invention does not change the development time, developer dilution rate, development temperature, etc. even if the sensitivity is doubled compared to the conventional one. It was found that the change in sensitivity was extremely small. or,
It was found that ink receptivity and printing durability did not deteriorate.

The present invention will be explained below with reference to Examples. However, the present invention is not limited to these. Note that % indicates weight % unless otherwise specified.

Synthesis Example 1 108g of 0-cresol, 90g of rose formaldehyde
And 200m1 of water! into a 1000-ml flask,
40% sodium hydroxide aqueous solution 1 at room temperature with stirring
00g was added at a temperature below 50°C, and then reacted at 50°C for 3 hours. After the reaction was completed, it was cooled to room temperature, neutralized with 10% aqueous hydrochloric acid solution, and 300 mI of methyl isobutyl ketone was added. added. After washing with water and separating, 200 g of 0-cresol was added, the temperature was raised to 50°C, concentrated hydrochloric acid 5- was added, and the mixture was reacted for 1 hour. Concentration under reduced pressure gave 150 g of a yellow solid. This yellow solid contains 15% by weight of heptadons or more and 85% by weight of hexanuclides or less.
- It was a cresol novolak resin.

Example 1 The surface of an aluminum slope with a thickness of 0.24 mm was grained using a nylon brush and 400 mesh of vamisu water suspension, and then thoroughly washed with water.

After etching was carried out by immersion in an IJium aqueous solution (10% hydroxide) at 50°C for 20 seconds, it was washed with running water (20°C) for 1 minute.

Next, using a 1.5% nitric acid aqueous solution, the voltage was 1 at 20°C.
Using a sine wave alternating current of 0 ■, the amount of electricity is 900 coulombs/d.
After performing electrochemical graining for 20 seconds at 70°C for 20 seconds, desmutting was performed by immersing the grain in 20% phosphoric acid at 70°C for 30 seconds.After thorough washing with water, 15% aqueous sulfuric acid
3.0 g /
An anodized film of m'' was provided.

On this support, the following photosensitive solution was spread and dried to form a photosensitive layer having a dry weight of 2.5 g/m'' to obtain a positive SP plate.

Photosensitive liquid: Esterified product of naphthoquinone-(1,2)-diazide-(2)-5-sulfonic acid chloride and pyrogallol acetone resin (as described in Example 1 of U.S. Pat. No. 3,635,709). ) 0.8 g Cresol formaldehyde resin 1.708 p-t-butylphenol resin 0.05 g Victoria Pure Blue BOHO, 05 g 2-trichloromethyl-5-p-butoxystyrene 1,3°4-oxa Diazole 0.06 g Ethylene dichloride 18 g 2-methoxyethyl acetate) 12 g As the cresol formaldehyde resin, the following were used.

Δ m-p-cresol novolac resin (m-form = p-form =
60: 40.50% by weight of 7-nuclear bodies or more, 50% by weight of 6-nuclear bodies or less) 1.7 gB <^
) with 1.3 g of resin and 7 or more nuclear bodies obtained in Synthesis Example 1.
0-cresol novolak resin with 5% by weight and 85% by weight of 6-nuclear bodies or less 0.4gC(A)
of resin and hexahydrophthalic anhydride
0.4g of this positive type 25 plate for one week.
After being left at room temperature and humidity, the film was exposed to light for 60 seconds through Fuji Photo Film (Gray Scale) from a distance of 1 m using a 3KW metal halide lamp as a light source. Then SiO
□/Na, O molar ratio is 1.2 and 5iOz content is 1.5
% sodium silicate aqueous solution at 25° C. for 1 minute and 5 minutes, and washed with water. The number of grayscale steps at each development time was read to determine the sensitivity value.

The relative sensitivity was as follows when the sensitivity of 1 minute development was set as 100.

Table 1 As shown in Table 1, although B shows 1.8 times the sensitivity as A, the change in sensitivity due to development time is slightly larger than A. On the other hand, C has a sensitivity of B
However, it can be seen that the sensitivity change due to development time is much larger than 8.

Claims (1)

[Claims] A positive photosensitive composition comprising an o-quinone diazide compound and an alkali-soluble novolak resin, characterized in that 5 to 40% by weight of the novolak resin is an o-cresol resin containing 75% by weight or more of hexanuclear bodies or less. A positive photosensitive composition.