JPH0619131A - Photosensitive composition - Google Patents

Abstract

PURPOSE:To improve sensitivity and development allowance and resistance against chemicals used for printing by using a phenol resin having specified glass transition temp. as a polymer having phenol-type hydroxyl groups. CONSTITUTION:This compsn. contains a quinone diazide compd. and a polymer having phenyl-type hydroxyl groups. The polymer having phenol-type hydroxyl groups is a phenol resin having 120-250 deg.C glass transition temp. Tg. This phenyl resin is obtd. by condensing phenols and formaldehyde in the presence of an acid catalyst. By dissolving these components in a solvent, applied on the surface of a proper supporting body, and drying, a photosensitive layer is obtd. The obtd. layer has excellent resistance against treating chemicals to be used and has higher sensitivity and development allowance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photosensitive composition suitable for a photosensitive lithographic printing plate, and more specifically, it has excellent resistance to a processing chemical used for printing, high sensitivity, and excellent development acceptability. The present invention relates to a photosensitive composition suitable for a lithographic printing plate.

[0002]

BACKGROUND OF THE INVENTION Positive-working photosensitive lithographic printing plates are resistant to various processing chemicals used during printing, such as isopropyl alcohol contained in fountain solution and solvents contained in ink, plate cleaners and the like. Is low and, as a result, the printing durability is reduced. Further, the development processing of the positive type photosensitive lithographic printing plate is usually carried out in a developing solution containing an alkaline aqueous solution, but the developing ability of the developing solution is susceptible to fluctuations under various conditions, for example, fatigue due to large-scale processing or air oxidation. In some cases, the developing ability is deteriorated due to deterioration, and the photosensitive layer in the non-image area of the printing plate may not be completely dissolved even if processed. Even with a developing solution with a low processing capacity,
It is desired to have a wide range of development acceptability that exhibits the same developability as in the case of processing with a standard developing solution (hereinafter, the allowable range of the decrease in developing ability for obtaining an appropriate development result is referred to as "underdeveloping property". ). As an attempt to improve resistance to processing chemicals used for printing, it is known to add a vinyl polymer or an acrylic polymer having a Tg of 100 to 300 ° C. having a phenolic hydroxyl group to the photosensitive composition (special feature). Kaihei 1-291245, Japanese Patent Laid-Open No. 1-291244). However, the vinyl polymer or acrylic polymer having a Tg of 100 to 300 ° C. having a phenolic hydroxyl group has the drawbacks of low sensitivity and low development tolerance.

[0003]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to have excellent resistance to processing chemicals used for printing and high sensitivity.
It is to provide a photosensitive composition suitable for a photosensitive lithographic printing plate having excellent development tolerance.

[0004]

The above object of the present invention is to provide a photosensitive composition containing at least a quinonediazide compound and a polymer having a phenolic hydroxyl group, wherein the polymer having a phenolic hydroxyl group is a phenol resin and a glass. It was achieved by providing a photosensitive composition characterized by a transition temperature (Tg) of 120-250 ° C.

The present invention will be described in more detail below.

Examples of the quinonediazide compound in the present invention include ester compounds of o-naphthoquinonediazide sulfonic acid and a polycondensation resin of phenols and aldehydes or ketones.

Examples of the above-mentioned phenols include monohydric phenols such as phenol, o-cresol, m-cresol, p-cresol, 3,5-xylenol, carvacrol and thymol, and divalent phenols such as catechol, resorcinol and hydroquinone. Examples include trihydric phenols such as phenol, pyrogallol, and phloroglucin. Examples of the aldehyde include formaldehyde, benzaldehyde, acetaldehyde, crotonaldehyde, furfural and the like. Preferred of these are formaldehyde and benzaldehyde. In addition, examples of the ketone include acetone and methyl ethyl ketone.

Specific examples of the polycondensation resin include phenol / formaldehyde resin, m-cresol / formaldehyde resin, m- and p-mixed cresol / formaldehyde resin, resorcin / benzaldehyde resin, pyrogallol / acetone resin. To be

The condensation rate of o-naphthoquinonediazide sulfonic acid with respect to the OH group of the phenol of the o-naphthoquinonediazide compound (reaction rate for one OH group) is
It is preferably 15 to 80%, more preferably 20 to 45%.

Further, as the quinonediazide compound used in the present invention, the following compounds described in JP-A-58-43451 can also be used. That is, for example, known 1,2-quinonediazide such as 1,2-benzoquinonediazidesulfonate, 1,2-naphthoquinonediazidesulfonate, 1,2-benzoquinonediazidesulfonate, 1,2-naphthoquinonediazidesulfonate. Compounds, more specifically J. Kosar, "Light-Sensitive Systems", pages 339-352 (1965), John Willie & Sons (Joh).
n Wiley & Sons (New York) and W.S. De Forest
Written "Photoresist"("Photoresist") Volume 50,
(1975), 1,2-benzoquinonediazide-4-sulfonic acid phenyl ester, 1,2, described in McGraw-Hill, Inc. (New York).
1 ', 2'-di- (benzoquinonediazide-4-sulfonyl) -dihydroxybiphenyl, 1,2-benzoquinonediazide-4- (N-ethyl-N-β-naphthyl)-
Sulfonamide, 1,2-naphthoquinonediazide-5-
Sulfonic acid cyclohexyl ester, 1- (1,2-naphthoquinonediazide-5-sulfonyl) -3,5-dimethylpyrazole, 1,2-naphthoquinonediazide-5-
Sulfonic acid-4 ″ -hydroxydiphenyl-4 ″ -azo-β-naphthol ester, N, N-di- (1,2-naphthoquinonediazide-5-sulfonyl) -aniline,
2 '-(1,2-naphthoquinonediazide-5-sulfonyloxy) -1-hydroxy-anthraquinone, 1,2
-Naphthoquinonediazide-5-sulfonic acid-2,4-dihydroxybenzophenone ester, 1,2-naphthoquinonediazide-5-sulfonic acid-2,3,4-trihydroxybenzophenone ester, 1,2-naphthoquinonediazide-5-sulfone 2 moles of acid chloride and 4,4'-
Condensate of diaminobenzophenone 1 mol, 1,2-naphthoquinonediazide-5-sulfonic acid chloride 2 mol and 4,4'-dihydroxy-1,1'-diphenylsulfone 1 mol, 1,2-naphthoquinonediazide- 5
Examples include 1,2-quinonediazide compounds such as a condensate of 1 mol of sulfonic acid chloride and 1 mol of purpurogallin, and 1,2-naphthoquinonediazide-5- (N-dihydroabietyl) -sulfonamide. In addition, Japanese Examined Japanese Patent Publication Nos. 37-1953, 37-3627, 37-13109, and 40-26126
No. 40, No. 40-3801, No. 45-5604, No. 45-27345, No. 51-1
3013, JP-A-48-96575, 48-63802, 48-63803
The 1,2-quinonediazide compounds described in each publication can also be mentioned.

As the orthoquinonediazide compound used in the present invention, the above compounds may be used alone or in combination of two or more kinds. The proportion of the quinonediazide compound used in the present invention in the photosensitive composition is preferably 5 to 60% by weight, particularly preferably 10 to
50% by weight.

The phenol resin of the present invention having a glass transition temperature of 120 to 250 ° C. (hereinafter referred to as “polymer compound of the present invention”) is a resin obtained by condensing phenols and formaldehyde in the presence of an acid catalyst. Examples of the phenols include phenol, o-cresol, m-cresol, p-cresol, 3,5-xylenol, 2,
4-xylenol, 2,5-xylenol, carvacrol, thymol, catechol, resorcin, hydroquinone, pyrogallol, phloroglucin and the like can be mentioned. The above phenol compounds may be used alone or in combination of two or more to condense with formaldehyde to obtain a resin.
Of these, preferred phenolic resins are phenol,
A resin obtained by copolycondensing at least one selected from m-cresol (or o-cresol) and p-cresol with formaldehyde, for example, phenol-formaldehyde resin, m-cresol-formaldehyde resin, o- Cresol / formaldehyde resin, phenol / p-cresol / formaldehyde copolymer resin, m-cresol / p-cresol / formaldehyde copolycondensate resin, o-cresol / p-cresol / formaldehyde copolycondensate resin, phenol / m -Cresol / p-cresol / formaldehyde copolycondensate resin and phenol / o-cresol / p-cresol / formaldehyde copolycondensate resin may be mentioned. In the present invention, among the above-mentioned phenol resins, phenol / m-cresol / p-cresol / formaldehyde resins represented by the following general formula are preferable.

[0013]

[Chemical 1]

In the present invention, the above phenolic resins may be used alone or in combination of two or more kinds.

In the phenol / m-cresol / p-cresol / formaldehyde resin, the amount of phenol is 0 to 50 mol%, preferably 0 to 20 mol%, more preferably 0 to 10 mol%, and m The amount of cresol is 10 to 60 mol%, preferably 20 to 50 mol%,
The amount of p-cresol is 10 to 50 mol%, preferably 20 to
40 mol%.

In the polymer compound of the present invention,
The amount of unreacted monomer is 5 mol% or less, preferably 2
It is not more than mol%.

Weight average molecular weight M of the polymer of the present invention
w is preferably 3.0 × 10 ^{2 to} 2.0 × 10 ⁴ , and more preferably 1.0 × 10 ^{3 to} 1.0 × 10 ⁴ .

The polymer compound of the present invention may have a glass transition temperature of 120 to 250 ° C., preferably the glass transition temperature is 120 to 200 ° C., more preferably 120 to 1 ° C.
60 ° C.

The proportion of the polymer compound of the present invention in the photosensitive composition of the present invention is 30 to 95% by weight, more preferably 50 to 90% by weight.

The photosensitive composition of the present invention may contain other additives, if necessary, in addition to the materials described above. Typical examples are various low molecular weight compounds as plasticizers such as phthalic acid esters, triphenyl phosphates and maleic acid esters, and surfactants as coatability improvers such as fluorochemical surfactants and ethyl cellulose polyalkylene ether. Examples include nonionic activators and the like, and printout materials and the like for forming a visible image by exposure. The printout material is composed of a compound that generates an acid or a free radical upon exposure to light and an organic dye that changes its color tone by interacting with the compound. Examples of the compound that generates an acid or a free radical upon exposure to light include O-naphthoquinonediazide-4-sulfonic acid halogenide described in JP-A-50-36209, JP-A-53-53
-36223, trihalomethyl-2-pyrone and trihalomethyl-triazine, and o-naphthoquinonediazide-4-, described in JP-A-55-6244.
Ester compounds of sulfonic acid chloride and phenols or anilines having electron-withdrawing substituents
Halomethyl-vinyl-described in 55-77742
Examples include oxadiazole compounds and diazonium salts.

Of these, halomethyl-vinyl-oxadiazole compounds are preferable, and especially JP-A-60-138539.
2-containing a heterocyclic group containing oxygen, such as a benzofuryl group, at the 5-position via a vinyl group,
More preferred are halomethyl-1,3,4-oxadiazole compounds.

Examples of the organic dyes include Victoria Pure Blue BOH [Hodogaya Chemical], Oil Blue # 603 [Orient Chemical], Patent Pure Blue [Sumitomo Mikuni Chemical], Crystal Violet,
Typical examples include brilliant green, ethyl violet, methyl green, erythrosine B, basic fuchsin, malachite green, oil red, m-cresol purple, rhodamine B, auramine, 4-p-diethylaminophenyliminonaphthoquinone, cyano-p-diethylaminophenylacetanilide. Examples thereof include triphenylmethane-based, diphenylmethane-based, oxazine-based, xanthene-based, iminonaphthoquinone-based, azomethine-based, and anthraquinone-based dyes. Of these, triphenylmethane dyes are preferable.

Further, a sensitizer for improving sensitivity can be added to the photosensitive composition of the present invention. Examples of the sensitizer include gallic acid derivatives described in JP-A-57-118237 and 5-membered cyclic acid anhydrides described in JP-A-52-80022, such as phthalic anhydride. , Tetrahydrophthalic anhydride, hexahydrophthalic anhydride, maleic anhydride, succinic anhydride, etc., and 6-membered cyclic acid anhydrides such as those described in JP-A-58-11932, for example glutaric anhydride and its Examples include derivatives. Of these, cyclic acid anhydrides are preferable, and 6-membered cyclic acid anhydrides are particularly preferable.

Further, a lipophilic resin may be added to the photosensitive composition of the present invention in order to improve the oil sensitivity of the photosensitive composition.

Each of these components is dissolved in the following solvent,
Further, by coating this on the surface of a suitable support and drying it, a photosensitive layer can be provided to form a photosensitive lithographic printing plate.

Solvents that can be used for dissolving each component of the photosensitive composition of the present invention include methyl cellosolve, methyl cellosolve acetate, ethyl cellosolve, cellosolves such as ethyl cellosolve acetate, dimethylformamide, dimethylsulfoxide, dioxane. , Acetone, cyclohexanone, trichloroethylene, methyl ethyl ketone and the like. These solvents may be used alone or in admixture of two or more.

As the coating method used for coating the above-mentioned photosensitive composition on the surface of the support, conventionally known methods such as spin coating, wire bar coating, dip coating, air knife coating, roll coating, blade coating and Curtain coating etc. are possible. At this time, the coating amount varies depending on the application, but for example, the solid content is preferably 0.5 to 5.0 g / m ² .

In the photosensitive lithographic printing plate of the present invention, the support on which the photosensitive layer is provided is a metal plate of aluminum, zinc, steel, copper or the like, and chromium, zinc, copper, nickel, aluminum, iron or the like is plated or vapor-deposited. Examples of the metal plate, paper, plastic film and glass plate, paper coated with resin, paper coated with metal foil such as aluminum, and plastic film subjected to hydrophilic treatment. Of these, the aluminum plate is preferable. As the support of the photosensitive lithographic printing plate of the present invention, it is more preferable to use an aluminum plate which has been subjected to surface treatment such as graining treatment, anodic oxidation treatment and, if necessary, sealing treatment.

Known methods can be applied to these treatments.

Examples of the graining treatment method include a mechanical method and an electrolytic etching method. Examples of mechanical methods include a ball polishing method, a brush polishing method, a liquid honing polishing method, and a buff polishing method. The above-mentioned various methods can be used alone or in combination depending on the composition of the aluminum material. The method by electrolytic etching is preferable.

Electrolytic etching is performed using phosphoric acid, sulfuric acid, hydrochloric acid,
It is carried out in a bath containing one or more inorganic acids such as nitric acid. After the graining treatment, if necessary, desmut treatment is performed with an aqueous solution of alkali or acid to neutralize and wash with water.

In the anodizing treatment, sulfuric acid, chromic acid, oxalic acid, phosphoric acid, malonic acid, etc. may be used alone or in combination as an electrolytic solution.
Electrolysis is performed using a solution containing at least one species and using an aluminum plate as an anode. The amount of anodized film formed is 1 to 50
mg / dm ² are suitable, preferably from 10 to 40 mg / dm ^2. The amount of anodic oxide film is, for example, a phosphoric acid chromic acid solution (phosphoric acid 85% solution: 35 ml, chromium oxide (V
I): 20 g dissolved in 1 liter of water)
It is determined by dissolving the oxide film and measuring the change in weight of the plate before and after the film is dissolved.

Specific examples of the sealing treatment include boiling water treatment, steam treatment, sodium silicate treatment, and dichromate aqueous solution treatment. In addition to this, the aluminum plate support may be subjected to an undercoating treatment with an aqueous solution of a water-soluble polymer compound or a metal salt such as fluorinated zirconic acid.

The photosensitive lithographic printing plate of the present invention can be developed by a usual method. For example, it is exposed through a transparent positive film with a light source such as an ultra-high pressure mercury lamp, a metal halide lamp, a xenon lamp, a tungsten lamp, and the like, and then developed with various alkaline developers. As a result, only the unexposed portion remains on the surface of the support, and a positive-positive relief image is formed.

Examples of the alkaline developer include alkali metal salts such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium metasilicate, potassium metasilicate, sodium diphosphate, and sodium triphosphate. An aqueous solution of The concentration of the alkali metal salt is preferably 0.1 to 10% by weight. If necessary, an anionic surfactant, an amphoteric surfactant, or an organic solvent such as alcohol can be added to the developer.

[0036]

【Example】

(Production of aluminum plate) A 0.24 mm thick aluminum plate (material 1050, tempered H16) was degreased in 5 wt% sodium hydroxide aqueous solution at 60 ° C for 1 minute, and then 1 liter of 0.5 mol hydrochloric acid was added. Electrolytic etching treatment was performed in an aqueous solution under the conditions of temperature: 25 ° C., current density: 60 A / dm ² , treatment time: 30 seconds. Then, after desmutting at 60 ° C. for 10 seconds in a 5 wt% sodium hydroxide aqueous solution,
Temperature in 20% by weight sulfuric acid solution; 20 ° C, current density; 3 A / dm
^2. Treatment time: Anodizing treatment was performed for 1 minute.
Further, hot water sealing treatment was performed with hot water at 30 ° C. for 20 seconds to prepare an aluminum plate as a support for a lithographic printing plate material.

A photosensitive composition coating solution having the following composition was applied to the aluminum plate prepared as described above using a wire bar and dried at 90 ° C. for 4 minutes to obtain a positive photosensitive lithographic printing plate sample. (Photosensitive composition coating liquid composition) -Quinonediazide compound 1.4 g-Polymer compound of the present invention shown in Table 1 (or comparative acrylic resin) 5.0 g-2-Trichloromethyl-5- (p-methoxystyryl) -1 , 3,4-Oxadiazole (Compound described in Example 1 of Japanese Examined Patent Publication No. 54-74728) 0.11 g-Victoria Pure Blue BOH (Hodogaya Chemical Co., Ltd.) 0.07 g-Methylcellosolve 100 ml Quinonediazide compound having the above composition Using the polymer compound of the present invention as shown in Table 1, photosensitive lithographic printing plate samples 1 to 4 were obtained.

A positive type film having a pattern was adhered to each of the obtained photosensitive lithographic printing plate samples 1 to 4 and a 2 KW metal halide lamp (Idlefin 2000 manufactured by Iwasaki Electric Co., Ltd.)
Was used as a light source under the conditions of 8.0 mW / cm. Next, SDR-1 (manufactured by Konica Corp.) was diluted 6 times with water to obtain a developing solution (standard developing solution), and 8 to 11 times with a developing solution (under developing solution). Development was performed at 25 ° C for 40 seconds. Visually observe the surface of the sample after treatment,
The evaluation was performed according to the evaluation criteria shown below. The results are shown in Table 1. Evaluation Criteria for Underdevelopment ◯: The photosensitive layer in the non-image area is completely dissolved and removed Δ: The photosensitive layer in the non-image area remains partially ×: Most of the photosensitive layer in the non-image area Not dissolved

In order to examine the chemical resistance to treatment, an ultra plate cleaner (UPC) (A.
B. C. Durability with respect to the developing ink PI-2 (manufactured by Fuji Photo Film Co., Ltd.) used in the developing ink plate and the developing ink plate was examined. The printing plate on which the image was formed was immersed in each of the processing solutions for a predetermined time (UPC: 2 hours, PI-
(2:30 minutes) After immersing, it was washed with water, and the degree of erosion of the image area with respect to the treatment chemical was determined by comparing with the image area before immersion. However, in the evaluation of the chemical resistance to treatment, the symbol "○" represents the state where the image area was not eroded.

The above results are shown in Table 1.

The clear sensitivity was determined according to the following method. The results are shown in Table 1. Clear sensitivity evaluation method Step tablets for sensitivity measurement on a photosensitive lithographic printing plate (Eastman Kodak No. 2, density difference 0.5 each 21
A 2 KW metal halide lamp (Idle Fin 2000, manufactured by Iwasaki Electric Co., Ltd.) was used as a light source and exposed under a condition of 8.0 mW / cm. Then add S to this sample
A developing solution (standard developing solution) obtained by diluting DR-1 (manufactured by Konica Corp.) 6 times with water was developed at 25 ° C. for 40 seconds. After processing, the number of stages in which the step tablet was completely developed was defined as the clear sensitivity.

[0042]

[Table 1]

[0043]

[Chemical 2]

As is clear from Table 1, the photosensitive lithographic printing plate of the invention was found to have excellent resistance to processing chemicals, high clear sensitivity, and excellent development acceptability.

[0045]

As described in detail above, a photosensitive composition suitable for a photosensitive lithographic printing plate which is excellent in resistance to a processing chemical used in printing according to the present invention, high in sensitivity, and excellent in development acceptability. Could be provided.

Front page continuation (72) Inventor Hideyuki Nakai 1 Sakura-cho, Hino-shi, Tokyo Konica stock company (72) Inventor Mitsuru Sasaki 1000 Kamoshida-cho, Midori-ku, Yokohama, Kanagawa Sanryo Kasei Co., Ltd. (72 ) Inventor Daisuke Kanazawa 1000 Kamoshida-cho, Midori-ku, Yokohama-shi, Kanagawa Sanryo Kasei Co., Ltd.

Claims (1)

[Claims] 1. A photosensitive composition containing at least a quinonediazide compound and a polymer having a phenolic hydroxyl group, wherein the polymer having a phenolic hydroxyl group is a phenol resin and has a glass transition temperature (Tg).
Is 120 to 250 ° C., a photosensitive composition.