JPS6259947A - Photosensitive composition - Google Patents

Abstract

PURPOSE:To manufacture a printing plate having good printing resistance power and developability and an excellent visible image characteristic and UV ink adaptability by incorporating a specific diazo resin, high-polymer compd. and oil-soluble dye into a titled compsn. CONSTITUTION:This compsn. is constituted of the diazo resin which is expressed by the formula I (X is PF6 or BF4, n>1) and contains >=15mol% component having >=5 n in the formula, the high-polymer compd. which contains 5-50mol% structural unit having an arom. hydroxyl group, 25-50mol% structural unit expressed by the formula II (R<1> is H, alkyl), 10-70mol% structural unit expressed by the formula III (R<2> is H, alkyl) and 5-15mol% structural unit expressed by the formula IV (R<3> is H, alkyl) and has 10,000-70,000 average mol.wt. and the oil-soluble dye. A (meth)acrylamide, etc. having the arom. hydroxyl group are preferable as the structural unit having the arom. hydroxyl group of the above-mentioned high-polymer compd. The visible image characteristic and particularly the developability at a low temp. is obtd. and the excellent printing resistance power is obtd. even in printing using not only general ink but UV ink as well by using the photosensitive material for copying obtd. by forming the coated film of such compsn. on, for example, an Al sheet.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a photosensitive composition, and in particular, a photosensitive composition having a property that allows visually distinguishing unexposed areas from exposed areas using yellow safe light. (visible image quality), printing durability, developability, and rl
The present invention relates to a negative photosensitive composition that provides a photosensitive layer suitable for V ink.

[Conventional technology]

The majority of materials used as photosensitive substances in printing materials that have been given photosensitivity in advance are diazonium compounds, and the most commonly used ones are diazo resins represented by formaldehyde condensates of p-diazodiphenylamine. There is. When such a diazo resin is coated on a suitable support such as paper, plastic or metal and exposed to actinic light through a transparent negative, the diazo resin in the exposed areas decomposes and becomes insoluble. do. On the other hand,
The surface of the support is exposed by dissolving and removing the unexposed area with water. If a support is used that has a surface that has been previously subjected to a hydrophilic treatment, the hydrophilic layer will be exposed in the unexposed areas through development. Therefore, on an offset printing press, this portion accepts water and repels ink. Furthermore, the diazo resin in the decomposed portion exhibits lipophilic properties, repelling water and accepting ink. Printing materials of this type give so-called negative-working printing plates.

The composition of the photosensitive layer of this type of photosensitive printing material is, for example, a diazo resin alone, that is, without using a polymer compound, as described in US Pat. It can be classified as a mixture of a polymer compound and a diazo resin as described in British Patent No. 1074592 and British Patent No. 1074592. In the former case, printing durability is poor, so the latter composition, which has good printing durability, is generally used.

Such polymer compounds include, for example, Japanese Patent Publication No. 55-3
A copolymer of (meth)acrylic acid and (meth)acrylonitrile having an alcoholic hydroxyl group as described in the specification of JP-A-56-4144, ) Copolymers of alkyl acrylates, (meth)acrylonitrile, and unsaturated carboxylic acids, (meth)acrylamides or (meth)acrylamides having an aromatic hydroxyl group as described in Japanese Patent Publication No. 57-43890 Acrylic ester, (meth)
Copolymers of acrylonitrile and unsaturated carboxylic acids are known.

[Problem that the invention seeks to solve]

However, with conventional photosensitive compositions, visible imageability, printing durability,
The developability was not necessarily sufficient, and improvement was desired.

It is an object of the present invention to provide a photosensitive composition that provides a immersed printing plate with good printing durability and developability, as well as visible imageability and UV ink suitability.

[Means for solving problems]

To summarize the present invention, the present invention relates to a photosensitive composition, and comprises the following components (al, (bl and (C)): (a) the following general formula 1: (wherein, X is PF , or BF, and n is a number of 1 or more), and in the formula, n is 5 or more. 5-5
0 mol%, the following general formula ■: -C horse-〇 -'...(II) N (in the formula, R1 represents hydrogen or an alkyl group) 25 to 50 moles of the structural unit represented by the following general formula ■ : ■ -ctqt-a-...(Ill) ■ 10 to 70 moles of structural units represented by cooa, horse (in the formula, HR represents hydrogen or an alkyl group), and the following general formula ■ ni-OH, -〇-φ...CM>00H Contains 5 to 15 mol% of the structural unit represented by (in the formula, Rs represents hydrogen or an alkyl group), and has a weight average molecular weight of 10,000 to 70,000. It is characterized by containing a polymer compound (Q) an oil-soluble dye.

The present invention will be explained in detail below.

The +al diazo resin component used in the present invention is represented by the general formula T1), and in this formula, n is usually 1 to 2.
00, but it is a diazo resin containing 15 mol or more of a compound with n of 5 or more, preferably 15 to 70 mol of a compound with n of 5 or more.

If the number of diazo resins in which n is 5 or more is less than 15 molar, that is, the diazo resin has a relatively low molecular weight, the adhesion between the photosensitive layer and the support is weak and sufficient printing durability cannot be obtained.

The diazo resin component of the present invention can be prepared by a known method, for example, Photographic Inc. Science and Engineering (Photo, 8ci, Efng, Vol. 17, p. 35 (b973), U.S. Patent Nos. 2063631 and 2679498). According to the method described in the specification,
It is obtained by polycondensing p-diazodiphenylamine and (para)formaldehyde in sulfuric acid, phosphoric acid, or hydrochloric acid.

At that time, p-diazodiphenylamine (para)formaldehyde is charged in a molar ratio of usually 1:α6 to 1:2, preferably 1:α7 to 1:1.5, and heated at a low temperature for a short time, e.g. 10°C or less. A high molecular weight diazo resin can be produced by reacting for about 3 hours. The diazo resin is prepared by a known method), PF6 salt or BP,
It is used as a salt as a diazo resin component of the present invention.

The diazo resin component of the present invention may be contained in the photosensitive composition in an amount of 1 to 30% by weight, preferably 7 to 20% by weight.

The Ctel polymer compound component used in the present invention has a structural unit having an aromatic hydroxyl group, the general formulas (II) to (I
Contains a structural unit represented by V).

Examples of the compound providing the structural unit having an aromatic hydroxyl group include (b) N-(4-hydroxyphenyl)acrylamide, N-(a-hydroxyphenyl)methacrylamide,
Methacrylamides or acrylamides having an aromatic hydroxyl group such as N-('-hydroya7su7tyl)methacrylamide, (2) o-1m-1 or p-hydroxyphenyl methacrylate, 〇-1m-1 or p Examples include methacrylic esters or acrylic esters having an aromatic hydroxyl group such as -hydroxyphenylacrylate, (3) '-1'' -1 or styrenes having an aromatic glacial group such as p-hydroxystyrene, etc. It will be done.

Examples of the compound that provides the structural unit represented by the general formula (U) include acrylonitrile and methacrylonitrile, and examples of the compound that provides the structural unit represented by the general formula (III) include acrylic acid ether. , ethyl methacrylate, and examples of the compound providing the structural unit represented by the general formula (V) include acrylic acid and methacrylic acid.

In the present invention, these compounds are copolymerized with other addition-polymerizable unsaturated compounds according to a conventional method to form the (b) polymer compound component of the present invention. Obtainable. Each structural unit of the polymer compound component obtained (middle) approximately corresponds to the charging ratio.

Examples of the addition polymerizable unsaturated compound include alkyl methacrylates or alkyl acrylates such as propyl methacrylate, propyl acrylate, butyl methacrylate, and butyl acrylate.

The content of the structural unit having an aromatic hydroxyl group in the (bl polymer compound component) used in the present invention is 5 to 50 mol%, preferably 7 to 40 mol%.
When it is low, there is a problem in storage stability, and when it exceeds 50 mol%, the oil sensitivity of the image area is significantly reduced. Also,
The content of the structural unit represented by the general formula (Ill) is 25
~50 mol 5, preferably 30-45 mol %. 2
If it is lower than 5 mol %, the improvement in UV ink suitability and printing durability, which is the object of the present invention, will not be observed, and if it exceeds 50 mol %, the oil sensitivity of the image area will be significantly reduced.

Further, the content of the structural unit represented by the general formula (I) is 10 to 70 mol%, preferably 20 to 60 mol%. If it is less than 10 mol %, the oil sensitivity of the image area will be significantly reduced, and if it exceeds 70 mol %, the improvement in UV ink suitability, which is the object of the present invention, will not be observed. Further, the content of the structural unit represented by the general formula (F/) is 5 to 15
Al in mol%, preferably 7-12 mol%. If it is lower than 5 mol%, it tends to reduce developability, and if it exceeds 15 mol%, it tends to reduce the oil sensitivity of the image area. Further, the weight average molecular weight of the polymer compound used as the 0)l component in the present invention is 10,000 to 70,000, preferably 15,000 to 60,000. If it is lower than 10,000, the film strength of the image area during development will decrease or sufficient sensitivity will not be obtained, and if it exceeds 70,000, the developability at low temperatures, which is the objective of the present invention, will be significantly reduced. do.

The polymer compound used as component (b)l in the present invention may be contained in the photosensitive composition of the present invention in an amount of 40 to 99% by weight, preferably 70 to 95% by weight.

Various known oil-soluble dyes can be used as component (0) in the present invention.

Among them, for example, Victoria Pure Blue B011
, Victoria Blue Base F-J R, Crystal Violet, Victoria Blue, Methyl Violet,
Oil Bruna 603, Rhodaline Blue, Diacrylic Black, etc. are preferred. These oil-soluble dyes are usually used in the photosensitive composition (L5 to 10 weight, preferably 1 to
It is preferable to contain 5 times ffi%.

Various additives can be added to the photosensitive composition of the present invention. Examples include alkyl ethers (e.g. ethyl cellulose, methyl cellulose, fluorine surfactants) and nonionic surfactants (e.g. Pluronic L-64 (manufactured by Asahi Denka Corporation)) to improve coating properties; Plasticizers (e.g., butylphthalyl, polyethylene glycol,
tributyl citrate, diethyl phthalate, diptyl phthalate, dihexyl phthalate, dioctyl phthalate, tricresyl phosphate, tributyl phosphate, trioctyl phosphate, tetrahydrofurfuryl oleate, oligomers of acrylic acid or methacrylic acid), image area Liposensitizing agents for improving oil sensitivity (e.g., alcohol-based styrene-maleic anhydride copolymer described in JP-A No. 55-527), -7 esters, etc.), known stabilizers [
For example, phosphoric acid, phosphorous acid, organic acids (citric acid, oxalic acid, tartaric acid, polyacrylic acid, benzenesulfonic acid, naphthalenesulfonic acid, 4-methoxy-2-hydroxybenzophenone-5-sulfonic acid, etc.)], etc. can be mentioned.

The amount of these additives added varies depending on the purpose of use, but is generally 0.01 to 30]i based on the total solid content.
Decrease by amount%.

The support to which the photosensitive composition of the present invention is applied may be, for example, paper, plastic, zinc, copper, aluminum, stainless steel, or a composite material made by laminating two or more of these materials. Among these, aluminum plates are particularly preferred.

However, if an aluminum plate is used without treatment, it has the disadvantage that the adhesion of the photosensitive composition is poor and the photosensitive composition decomposes. In order to eliminate this drawback, various proposals have been made in the past.

For example, a method in which the surface of an aluminum plate is grained and then treated with silicate (US Pat. No. 2,714,066);
Methods of treatment with organic acid salts (US Pat. No. 2,714,066), methods of treatment with phosphonic acids and their derivatives (US Pat. No. 3,220,832), methods of treatment with potassium hexafluorozirconate (US Pat. No. 29,466).
No. 85), a method of anodizing, and a method of treating with an aqueous solution of an alkali metal silicate after anodizing (US Pat. No. 31)
81461) etc.

In the present invention, the surface of the aluminum plate (including the alumina laminate, the same applies hereinafter) on which the photosensitive composition is installed is degreased, and then brush polishing, pole polishing, chemical polishing, and electrolytic etching are applied. Graining is preferably carried out by an electrolytic etching method that produces deep and uniform grains. The anodizing treatment is carried out in an aqueous solution of an inorganic acid such as phosphoric acid, chromic acid, boric acid, sulfuric acid, or an organic acid such as oxalic acid, or a mixture of two or more of these acids, preferably in an aqueous sulfuric acid solution. This is done by passing electric light through the plate as an anode. The amount of anodic oxide film is 5 to 60 ■/
am" is preferable, more preferably 5 to 50 ■/a
If the ratio is lower than 5 to /am, the adhesion between the photosensitive layer and the aluminum plate will be poor, and if it exceeds 60 to /am, the image reproducibility will be poor. The sealing treatment applied to the present invention is a sodium silicate aqueous solution with a concentration of α1 to 3.
%, by immersion at a temperature of 80 to 95°C for 10 seconds to 2 minutes, preferably followed by immersion in water at 40 to 95°C for 10 seconds to 2 minutes.

The aluminum plate treated as described above has a moderate affinity with the photosensitive composition of the present invention, has high adhesion to the photosensitive layer, and has a high adhesiveness to the photosensitive composition in the non-image area after development. It does not leave any residue on its surface, has high water retention, and has strong surface properties.

The photosensitive material for copying is coated on the support by conventional methods. That is, by exposing a transparent original image having a line image, a halftone image, etc. to light, and then developing it with an aqueous developer, a negative relief image can be obtained with respect to the original image. Light sources suitable for exposure include carbon arc lamps, mercury lamps, xenon lamps, metal noride lamps, strobes, and the like.

The developer used in the development of the photosensitive printing plate according to the present invention may be any known developer, but the following are preferred. That is, the developer for developing the photosensitive printing plate according to the present invention may be water or an aqueous solution containing a specific organic solvent and/or alkaline agent. Here, the specific organic solvent is one that can dissolve or swell the non-exposed area (non-image area) of the above-mentioned photosensitive composition layer when contained in the developer, and that is resistant to water at room temperature (20°C). refers to an organic solvent with a solubility of 10% by weight or less. Such organic solvents only need to have the above-mentioned characteristics, and are not limited to the following, examples of which include ethyl acetate, propyl acetate, etc. Carboxylic acid esters such as , acetic acid brush, diamyl acetate, benzyl acetate, ethylene glycol monobutyl acetate, butyl lactate, butyl levulinate: Ketones such as ethyl butyl ketone, methyl imbutyl ketone, cyclohexanone: ethylene glycol monobutyl ether , ethylene glycol benzyl ether, ethylene glycol monophenyl ether, benzyl alcohol, methylphenyl carbinol, n-7 methyl alcohol, methyl amyl alcohol: Alkyl-substituted aromatic hydrocarbons such as xylene: methylene dichloride , ethylene dichloride, and unahalogenated hydrocarbons such as monochlorobenzene. One or more of these organic solvents may be used. Among these organic solvents, ethylene glycol monophenyl ether and benzyl alcohol are particularly effective. In addition, the content of these organic solvents in the developer is approximately 1 to 1.
More preferable results are obtained when the amount is 20% by weight, especially 2 to 10% by weight.

On the other hand, the alkaline agents contained in the developer include sodium silicate, potassium silicate, potassium hydroxide, sodium hydroxide, lithium hydroxide, sodium or ammonium salts of dibasic or tertiary phosphoric acid, and metasilicic acid. Inorganic alkaline agents such as sodium, sodium carbonate, ammonia, etc. 031 Mono-, di- or trimethylamine, mono-, di- or triethylamine, mono- or diisopropylamine,
Examples include organic amine compounds such as n-bunalamine, mono-, di-, or triethanolamine, mono-, di-, or triisopropano-, ruamine, ethyleneimine, and ethylenediamine.

The content of these alkaline agents in the developer is usually 10
5 to 4% by weight, preferably (L5 to 2% by weight).

Further, in order to improve storage stability, printing durability, etc. to 9 or higher, it is preferable to include a water-soluble sulfite in the developer. Such water-soluble sulfites are preferably alkali or alkaline earth metal salts of sulfite, such as sodium sulfite, potassium sulfite, lithium sulfite, and magnesium sulfite. The content of these sulfites in the developer composition is usually 105 to 4% by weight, preferably 11 to 1% by weight.

Certain solubilizers may also be included to aid in the dissolution of the organic solvents mentioned above in water. As such a solubilizing agent, in order to achieve the desired effect of the present invention, it is preferable to use a low-molecular alcohol or ketone that is easily water-soluble in the organic solvent used. Furthermore, anionic activators, amphoteric activators, etc. can also be used. Examples of such alcohols and ketones include methanol, ethanol,
It is preferable to use propatool, butanol, acetone, methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methoxybutanol, ethoxybutanol, 4-methoxy-4-methylbutanol, N-methylpyrrolidone, and the like. Preferred examples of the activator include sodium inpropylnaphthalene sulfonate, sodium n-butylnaphthalene sulfonate, sodium N-methyl-N-pentadecylaminoacetate, and sodium lauryl sulfate. There are no particular restrictions on the amount of solubilizing agents such as alcohols and ketones used, but it is generally preferred to use an amount of about 30% by weight or less based on the entire developer.

Examples of synthesis of the diazo resin and polymer compound used in the present invention and examples of production of aluminum plates will be shown below.

(Synthesis of diazo resin-1) p-diazodiphenylamine sulfate 1451F (50 mmol) was dissolved in 4α92 concentrated sulfuric acid under water cooling. To this reaction solution, 1.55 t (45 mmol) of rose formaldehyde was slowly added dropwise. At this time, the reaction temperature is 1
It was added so that the temperature did not exceed 0°C. Thereafter, stirring was continued for 2 hours under water cooling.

This reaction mixture was added dropwise to 500-ml ethanol under water cooling, and the resulting precipitate was filtered. After washing with ethanol, this precipitate was dissolved in 100-100% pure water, and 68% pure water was added to this solution. A cold concentrated aqueous solution of zinc chloride was added. The resulting precipitate was filtered, washed with ethanol, and dissolved in 150-pure water. To this liquid was added a cold concentrated aqueous solution in which 82 ammonium hexafluorophosphate was dissolved. The resulting precipitate was collected, washed with water, and then dried at 50° C. for one day and night to obtain diazo resin-1.

When the molecular weight of the diazo resin-1 was measured by gel permeation chromatography (hereinafter abbreviated as GPC), it was found that it contained about 50 mol% of pentamers or more.

(Synthesis of diazo resin-2) The amount of paraformaldehyde was changed to 10 instead of 1.35 f.
Diazo resin-
It was synthesized in the same manner as in 1 to obtain diazo resin-2. When this diazo resin-2 was measured by APA, it was found that 51 or more resins were present in an amount of about 20 mol %.

(Synthesis of diazo resin-3) (Comparative example) When the amount of paraformaldehyde was 1.35 t, α9
Diazo resin-
It was synthesized in the same manner as in 1 to obtain diazo resin-3. When this diazo resin-3 was measured by GPO, it was found that the content of pentamers or more was about 11 mol %.

(Synthesis of diazo resin-4) (Comparative example) Instead of p-diazodiphenylamine sulfate 145F,
5-Methoxy-4-diazodiphenylamine sulfate 14
Diazo resin-1 except that it was changed to 11F (50 mmol)
It was synthesized in the same manner as above to obtain diazo resin-4.

(Synthesis of copolymer-1) H-(a-hydroxyphenyl) methacrylamide 17
．． 7f, acrylonitrile 17. Of.

Ethyl acrylate 4&Of, methacrylic acid a6t (m
yp/hx/xh/Mhh■10/32/A 8/10
molar ratio) was dissolved in a mixed solution of acetone 95- and methanol 95-, and azobisinbutyronitrile 532 was added thereto, and the mixture was heated under reflux (approximately 55 to 60°C) under a nitrogen atmosphere for about 8 hours.
) was subjected to a polymerization reaction. After the reaction was completed, the reaction solution was poured into water to precipitate the copolymer, which was vacuum-dried at 50° C. overnight. The weight average molecular weight of this copolymer-1 was determined to be 41,000 by GPC measurement.

(Synthesis of copolymer-2) p-hydroxyphenyl methacrylate (hereinafter abbreviated as MOP) 55,5f, acrylonitrile 1a6r, ethyl acrylate 2 & OIF, methacrylic acid & 0
(MOP /AN, /HA /MAA =
SO/S s728/7 molar ratio) was dissolved in a mixed solution of 95-acetone and 95-methanol, 53v of azobisisobutyronitrile was added, and the polymerization reaction was carried out at reflux temperature for about 8 hours under a nitrogen atmosphere. went. After the reaction was completed, the reaction solution was poured into water to precipitate the copolymer, which was vacuum-dried at 80° C. for one day. The weight average molecular weight of this copolymer-2 is
From the GPQ measurement, it was 50,000.

(Synthesis of copolymer-3) MOP 44.5 r, acrylonitrile 1 work 5? .

methacrylic acid ether as, 6y, methacrylic acid a6f
(MOP/AN/EMA7/, MAA-25/25
/40/I 0 molar ratio) was dissolved in a mixed solution of 80% of acetone and 80% of methanol, azobisisobutyronitrile was added, and a polymerization reaction was carried out at reflux temperature for about 8 hours under a nitrogen stream. Ta. Post-treatment after the completion of the reaction consists of copolymer-
Copolymer-3 was obtained in the same manner as in Example 2.

The weight average molecular weight was 60,000 as determined by Q PO measurement.

(Synthesis of copolymer-4) p-hydroxystyrene 3&Of, acrylonitrile 1
19? , ethyl acrylate 3[lLo? , methacrylic acid a6t (pHs/Am/ma/Mmu-5o15
The mixture was dissolved in a mixed solution of 90 WIt of acetate and 9 Ω of methanol, 55 tons of azobisisobutyronitrile was added, and a polymerization reaction was carried out at reflux temperature for about 8 hours under a nitrogen stream. Post-treatment after the completion of the reaction was carried out in the same manner as Copolymer-2 to obtain Copolymer-4. The weight average molecular weight was 550,000 as determined by GPO measurement.

(Synthesis of Copolymer-5) (Comparative Example) As the amount of monomer, N-(p-hydroxyphenyl)
Methacrylamide 17.7f, acrylonitrile 1 [L
6F, 7iri IJ le f9 x f le 6αO21 methacrylic acid a 6t (uyp/AN/mA/uaa-1o/
Copolymer-1 except that the molar ratio was 20/60/10
Synthesis was carried out in the same manner as above to obtain copolymer-5.

The weight average molecular weight was 430,000 as measured by GPO.

(Synthesis of copolymer-6) (Comparative example) Ethyl acrylate 4&0? butyl acrylate b
t s t (gyp/AN/nA/uAA-1o/
Copolymer-6 was synthesized in the same manner as Copolymer-1 except that s2/48/1 was used. The weight average molecular weight was 40,000 as measured by GPO.

(Synthesis of Copolymer-7) (Comparative Example) Monomer amounts: 17.7 t of N-(p-hydroxyphenyl)methacrylamide, 31.9 t of acrylonitrile.
F, acrylic acid ether 2α0? , methacrylic acid 11L
6 f (HyP/AN/1!A/MAA -1o/6
Copolymer-7 was synthesized in the same manner as Copolymer-1 except that Copolymer-7 was changed to (o/20/10). The weight average molecular weight was 590,000.

(Synthesis of Copolymer-8) (Comparative Example) Synthesis was carried out in the same manner as Copolymer-1 except that the amount of azobisinbutyronitrile was 1.Of.
I got 8. The weight average molecular weight was 95,000.

(Aluminum plate-1) An aluminum plate was immersed in a 3% sodium hydroxide aqueous solution to degrease it, washed with water, and then soaked in a 1% hydrochloric acid and 1% boric acid aqueous solution at 25°C.
Electrolytically etched for 5 minutes at a current density of 3 A/a-, washed with water, crushed in a 9% aqueous sodium hydroxide solution, washed with water, and etched at 1.5 A/d- in a 40% aqueous sulfuric acid solution at 30°C.
Anodize for 2 minutes at a current density of
It was immersed in Ha5 for 25 seconds, washed with water and dried to produce aluminum plate-1.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to Examples.
The invention is not limited to these examples.

Examples 1 to 5 and Comparative Examples 1 to 3 The photosensitive liquids (b) to (in Table 1) were applied to the aluminum plate-1.
5) and photosensitive solutions (6) to (8) for comparison were applied using a whirler and dried at 80° C. for 3 minutes to obtain photosensitive planographic printing plates (4) to (6). Dry coating weight is 1.7 tons
/ It was Ina 2.

Table-1 Table-1 (continued) After exposing the photosensitive lithographic printing plates (8) to (6) for 30 seconds from a distance of 60°C using a 3kW ultra-high pressure mercury lamp, the exposed and unexposed areas were Macbeth reflection densitometer RD51 to measure density difference
4 was measured through a visual filter, and the results shown in Table 2 below were obtained.

In Table 2, a density difference of 0.20 or more was considered to be good in visible image quality, and a density difference n of less than 20 was considered to be poor in visible image quality.

On the other hand, the photosensitive lithographic printing plate image ~σ field was imagewise exposed for 30 seconds from a distance of 60 images using a 3 kW ultra-high pressure mercury lamp. Then,
Developed at 25°C for 45 seconds using the following developer (b),
A lithographic printing plate was obtained.

Current & Liquid (b) These lithographic printing plates were printed on high-quality paper using a Heidelberg GTO printing machine using general ink (Toyo Ultra King Red), and the printing durability was examined, as shown in Table 2. Various results were obtained.

Furthermore, in order to examine suitability for TJv ink, a 1-immersion test and printing with Uv ink were performed.

In the immersion test, a lithographic printing plate obtained by exposing and developing K1 Best Cure UV Ink Roll Cleaner (manufactured by Natsukusa Shiki Kagaku Kogyo Co., Ltd.), which is a cleaner used in printing with UV ink, was immersed for one day and night. The ratio of the reflection density of the image area before the test to the reflection density of the image area after the test was measured. A ratio of 70% or more was considered good, and a ratio of less than 70% was considered poor. The results are shown in Table-2.

Printing with U4 ink was carried out using a Heidelberg ()To printing machine equipped with an aV irradiation device, and as rJv ink.
Printing was performed on high-quality paper using Best Cure manufactured by Natsuso Shiki Kagaku Kogyo Co., Ltd., and the printing durability was examined, and the results shown in Table 2 were obtained.

Table 2 shows that the photosensitive composition of the present invention exhibits good visible image quality and is significantly superior to conventional compositions not only in printing with general inks but also in printing with inks.

Example 6 The following photosensitive liquid (9) was applied to the aluminum plate-1 in the same manner as in Examples 1 to 5 to obtain a photosensitive lithographic printing plate (b). This was done from a distance of 60611 using a 3kW ultra-high pressure mercury lamp.
After image exposure for 0 seconds, 20
℃ (normal temperature) and 15℃ (low temperature) for 40 seconds,
The obtained planographic printing plate was printed with general ink under the same conditions as in Examples 1 to 5, and the presence or absence of stains in the non-image area and the printing durability of the obtained planographic printing plate were examined at room temperature. I looked into it. The results are shown in Table-3.

Photosensitive liquid (9) Examples 7 to 9 Instead of copolymer-1, copolymers-2, -3, and
Photosensitive iα1, α force, and (6) were prepared in the same manner as photosensitive solution (9) except that the photosensitive solution was changed to −4.

These photosensitive solutions were applied to the aluminum plate-11C Example 1.
- Coated in the same manner as in 5, photosensitive lithographic printing plate (sword, (3),
and - were obtained. After performing exposure and development processing in the same manner as in Example 6, printing was performed in the same manner as in Example 6, and the presence or absence of stains in the non-image area and printing durability were examined. The results are shown in Table 3. Indicated.

Comparative Examples 4 and 5 Copolymer-7 and -8 were used instead of Copolymer-1, respectively.
Add photosensitive liquid (6) in the same manner as photosensitive liquid (9) except that
) and α◆ were prepared. These photosensitive solutions were applied to the aluminum plate-1 in the same manner as in Examples 1 to 5 to obtain photosensitive planographic printing plates (Corporate) and (5). After exposing and developing these in the same manner as in Example 6, printing was performed in the same manner as in Example 6, and the presence or absence of stains in the non-image area and printing durability were examined. The results are shown in Table 3. Indicated.

Table 3 From Table 3, it can be seen that the photosensitive composition of the present invention is excellent in developability, especially developability at low temperatures, and is also excellent in ink receptivity.

Example 10 The following photosensitive liquid was applied to the aluminum plate-1 in Example 1.
Coating was carried out in the same manner as in steps 5 to 5 to obtain a photosensitive planographic printing plate (3).

This was performed for 1 minute from a distance of 6000 using a 5kW high-pressure mercury lamp.
After image exposure, in the development group (b), 25°C, 45°C.
A second development process was performed to obtain a lithographic printing plate. This was printed with I7' ink under the same conditions as Examples 1 to 5, and the printing durability was examined. The results are shown in Table-4.

Photosensitive liquid (total) Comparative Example 6 Except for using diazo resin-4 instead of diazo resin-1,
A photosensitive mast solution was prepared using the same recipe as the photosensitive solution (g).

I got it. These were image-exposed and developed in the same manner as in Example 10 to obtain a lithographic printing plate. This was printed with UV I/O under the same conditions as in Example 10, and the printing durability was examined. The results are shown in Table-4.

Table 4 From Table 4, it can be seen that the photosensitive composition of the present invention has much better suitability for 111rv ink than the conventional composition.

Example 11 The following photosensitive liquid (b) was applied to the aluminum plate-1 in the same manner as in Examples 1 to 5 to obtain a photosensitive lithographic printing plate (5). This was imagewise exposed for 1 minute from a distance of 60 mm using a 5 kW high-pressure mercury lamp, and then developed at 15° C. for 1 minute and 40 seconds using the developer (b) or the developer (2) below. Thereafter, printing was performed using general ink under the same conditions as in Examples 1 to 5, and the presence or absence of stains in the non-image areas was examined.

In addition, printing with Uv ink was performed under the same conditions as in Examples 1 to 5, and the printing durability was examined. The results are shown in Table-5.

Photosensitive solution αη Developer (2) Example 12 A photosensitive solution (to) was prepared using the same recipe as the photosensitive solution α, except that copolymer-21CL was used instead of copolymer-1, and the aluminum plate-1 was prepared. was coated in the same manner as in Example 11 to obtain a photosensitive lithographic printing plate (plow). This was evaluated in the same manner as in Example 11, and the results are shown in Table 5.

Table 5 Table 5 shows that the photosensitive composition of the present invention has excellent developability at low temperatures and excellent suitability for UV inks.

〔Effect of the invention〕

As explained above, if the photosensitive composition of the present invention is used, it has excellent visible image properties and developability, especially developability at low temperatures, and is excellent in printing not only with general inks (but also with trV inks). A remarkable effect is obtained in that a photosensitive layer having high printing durability can be obtained.

Claims (1)

[Claims] 1. Each of the following components (a), (b) and (c): (a)
The following general formula I ▲There are mathematical formulas, chemical formulas, tables, etc.▼...(I) (wherein, Diazo resin containing 15 mol% or more of the above, (b) 5 to 50 mol% of structural units having aromatic hydroxyl groups, the following general formula II: ▲There are mathematical formulas, chemical formulas, tables, etc.▼...(II) ( (In the formula, R^1 represents hydrogen or an alkyl group) 25 to 50 mol% of the structural unit represented by the following general formula III: ▲There are mathematical formulas, chemical formulas, tables, etc.▼...(III) (In the formula, 10 to 70 mol% of the structural unit represented by (R^2 represents hydrogen or an alkyl group), and the following general formula IV: ▲There are numerical formulas, chemical formulas, tables, etc.▼...(IV) (In the formula, R^ 3 represents hydrogen or an alkyl group) and has a weight average molecular weight of 10,000 to 70,000; (c) contains an oil-soluble dye; A photosensitive composition characterized by: 2. The structural unit having an aromatic hydroxyl group in the component (b) is a unit selected from the group consisting of acrylamides, methacrylamides, acrylic esters, methacrylic esters, and styrenes having an aromatic hydroxyl group. The photosensitive composition according to claim 1, which is a structural unit derived from a polymer.