JPH0340380B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a photosensitive composition suitable for producing lithographic printing plates. More specifically, the present invention relates to a photosensitive composition comprising an o-quinonediazide compound and an alkali-soluble polymer compound. Lithographic printing is a printing method that skillfully takes advantage of the property that water and oil essentially do not mix.The printing plate surface has two areas: one area that accepts water and repels oil-based ink, and the other area that repels water and accepts oil-based ink. The stronger these properties are, the easier it is to produce high-quality printed matter. Conventionally, in order to improve these properties, a method has been used in which developing ink is applied to the image surface in the plate-making process after exposure to improve ink receptivity (oil sensitivity). However, this method complicated the plate-making process and required time and effort since the plate was coated with developing ink. For this purpose, a method of adding a substituted phenolic aldehyde resin, particularly a tertiary-butylphenol formaldehyde resin, to a photosensitive composition containing an o-quinonediazide compound was disclosed in JP-A-50-125806. The addition of tertiary butylphenol formaldehyde resin certainly improves the oil sensitivity of the image area compared to the case without the addition, but on the other hand, a portion of the photosensitive composition tends to remain in the non-image area after development. Summer.
In particular, when absorbent cotton, sponge, etc. are soaked with a developer and developed by rubbing the printing plate, the photosensitive composition remains partially in the non-image area, which not only spoils the appearance but also often causes scumming. As a method for solving this problem, Japanese Patent Application Laid-open No. 50-36206 discloses the use of a photosensitive resin obtained by condensing a resin insoluble in an alkaline aqueous solution such as a tertiary butylphenol formaldehyde resin with a sulfonyl chloride of o-quinonediazide. A method was proposed. However, since the resin to be condensed with the sulfonyl chloride of o-quinonediazide is insoluble in the alkaline aqueous solution, there were problems such as a decrease in sensitivity. Therefore, the object of the present invention is to improve ink receptivity (oil sensitivity).
An object of the present invention is to provide a photosensitive composition that provides an image rich in color. Another object of the present invention is to provide a photosensitive composition that has high sensitivity, does not easily leave the photosensitive composition in non-image areas after development, and is unlikely to cause scumming. In order to achieve the above object, the present inventors have conducted various studies and found that a condensation product of a sulfonyl halide such as the sulfonyl chloride of o-quinonediazide and a polymer compound having a structure represented by the following general formula () It has been found that a photosensitive composition characterized by containing the above objects achieves the above object. (In the formula, R ₁ and R ₂ are each a hydrogen atom or a carbon number 1
~4 lower alkyl groups, R ₃ is an alkyl group having 4 to 15 carbon atoms or a cycloalkyl group having 4 to 15 carbon atoms, R ₄ and R ₅ are each a hydrogen atom, lower alkyl having 1 to 3 carbon atoms represents a group or a halogen atom, x is
Shows 10-90 mol%. ) The polymer compound represented by the general formula () is The present invention is essentially different from the invention disclosed in JP-A-50-36206 because the constituent components represented by are soluble in a developer (alkaline aqueous solution). Also, special public service in 1977
-24361 Publication describes at least one type of lower phenol selected from phenol, cresol and xylenol, and the general formula

Disclosed is a photosensitive resin obtained by reacting a quinonediazide compound with a co-condensate of at least one higher phenol represented by the formula [Formula] (wherein R is a 10-20 hydrocarbon group) and formaldehyde. . However, the invention is characterized in that the hydrocarbon group attached to the polyhydric phenol having two hydroxyl groups on the same benzene ring is higher (10 to 20 carbon atoms); The phenols have a relatively high-grade hydrocarbon group. Furthermore, since the objectives of the two inventions are also different, it can be said that the two inventions are essentially different. In the general formula (), R ₁ and R ₂ each represent a hydrogen atom or a lower alkyl group having 1 to 4 carbon atoms, preferably a hydrogen atom, a methyl group, or an ethyl group, and more preferably a hydrogen atom. R ₃ is an alkyl group having 4 to 15 carbon atoms or a cycloalkyl group having 4 to 15 carbon atoms, and preferred examples thereof include tertiary butyl group, tertiary octyl group, normal octyl group, cyclohexyl group, pentadecyl group, etc. . R ₄ and R ₅ are a hydrogen atom, a lower alkyl group having 1 to 3 carbon atoms, or a halogen atom, preferably a methyl group, an ethyl group, a chlorine atom, or a hydrogen atom, and more preferably a hydrogen atom. It is.
x is 10 to 90 mol%, preferably 20 to 70 mol%. In addition, the molecular weight of the polymer compound represented by the general formula () may be approximately 500 to 10,000 in order to effectively serve the purpose of the present invention, but preferably approximately 800 to 4,000. is appropriate. The polymer compound represented by the general formula () in the present invention is synthesized as follows. That is, resorcin, 4-tert-butylphenol, 4-n-octylphenol, 4-
A mixture of phenols such as pentadecylphenol at a molar ratio of 1:9 to 9:1, formaldehyde, acetone, acetaldehyde,
Aldehyde ketones such as methyl ethyl ketone are dissolved alone or in a solvent such as alcohol or dioxane, and an acid such as hydrochloric acid or oxalic acid or an alkali such as sodium hydroxide or aqueous ammonia is used as a catalyst.
The desired polymer compound can be obtained by condensing the aldehyde or ketone in an amount of 0.85 to 1.0 mol part per 1 mol part of the mixture of resorcinol and phenol. At this time, phenols and aldehydes/ketones can be freely combined with each other, and two or more types may be mixed and co-condensed. Examples of the sulfonyl chloride compound of o-quinonediazide used in the present invention include 1,2
Examples include -benzoquinone-2-diazide-4-sulfonyl chloride, 1,2-naphthoquinone-2-diazide-4-sulfonyl chloride, and 1,2-naphthoquinone-2-diazide-5-sulfonyl chloride. A condensation product of a sulfonyl halide such as the sulfonyl chloride of o-quinonediazide and a polymer compound represented by the general formula () is synthesized as follows. That is, o-quinonediazide such as sulfonyl chloride and the polymer compound are mixed with dioxane, methyl ethyl ketone, tetrahydrofuran, dimethylformamide (DMF).
Dissolved in a solvent such as room temperature or 40~50℃
It is easily esterified by adding an alkali such as sodium carbonate to the mixture under heating and stirring. The reaction ratio of acid chloride to the polymer compound represented by the general formula () is 1:0.1 to 1:2 by weight.
can be used, but the optimum ratio is between 1:0.3 and 1:1. A typical synthesis example of the condensation product of the o-quinonediazide compound and the polymer compound represented by the general formula () in the present invention will be shown. Synthesis Example 1 110 g of resorcin and 206 g of p-n-octylphenol were dissolved in 500 ml of 1,4-dioxane, and 162 g of 37% formalin was added thereto with stirring. Further, 1 ml of 5N hydrochloric acid was added as a catalyst, and the mixture was gently heated to reflux while being careful not to cause bumping. After 5 hours, the reaction mixture was poured into cold water 3, and the precipitated pale yellow resin was separated and dried. As a result, 306 g
was gotten. The molecular weight of this resin was determined to be approximately 2,200 using a light scattering method. 17g of this resin was mixed with methyl ethyl ketone/DMF.
(5/1) 1 and 2 dissolved in 60ml and prepared separately
-Naphthoquinone-2-diazide-5-sulfonyl chloride 17g of methyl ethyl ketone/DMF
(5/1) Added to 90ml solution. After stirring at room temperature for 1 hour, 6.4g of triethylamine was added dropwise, 5ml of water was added, and the reaction system was quenched with triethylamine.
The pH was adjusted to 6.0-6.5. This reaction solution was poured into 1.2 liters of cold water while stirring, and the precipitated yellow powder was collected. After purification by reprecipitation and drying, 27 g was obtained. The esterification rate per unit skeleton of the resin calculated from the UV spectrum was 44%. Synthesis Example 2 132 g of resorcinol and 243 g of m-pentadecylphenol were dissolved in 500 ml of 1,4-dioxane, and 162 g of 37% formalin was added thereto with stirring. Further, 1 ml of 5N hydrochloric acid was added as a catalyst, and the mixture was gently heated to reflux while being careful not to cause bumping. After 5 hours, the reaction mixture was poured into cold water 3, and the precipitated pale yellow resin was separated and dried. As a result, 310 g
was gotten. The molecular weight of this resin was measured using a light scattering method and was found to be approximately 1,500. 20g of this resin was mixed with methyl ethyl ketone/DMF.
(5/1) 1 and 2 dissolved in 60ml and prepared separately
-Naphthoquinone-2-diazide-5-sulfonyl chloride 20g of methyl ethyl ketone/DMF
(5/1) Added to 90ml solution. After stirring at room temperature for 1 hour, 7.5g of triethylamine was added dropwise.
Furthermore, 5 ml of water was added, and the pH of the reaction system was adjusted to 6.0 to 6.5 with triethylamine. This reaction solution was poured into 1.2 liters of cold water while stirring, and the precipitated yellow powder was collected. After purification by reprecipitation, 31 g was obtained as a result of drying. The esterification rate per unit skeleton of the resin calculated from the UV spectrum was 52%. The amount of the o-quinonediazide compound in the present invention in the photosensitive composition is 0.1 to 50% by weight, more preferably 0.5 to 20% by weight, and most preferably
It is 0.5 to 5% by weight. Although the o-quinonediazide compound of the present invention alone may be used as a photosensitive component in the photosensitive composition of the present invention, it is preferable to use it together with a known o-naphthoquinonediazide compound. Known o-naphthoquinone diazide compounds include 1, which is described in Japanese Patent Publication No. 43-28403;
Most preferred is an ester of 2-naphthoquinone-2-diazido-5-sulfonyl chloride and pyrogallol-acetone resin. Other suitable known orthoquinone diazide compounds include esters of 1,2-diazonaphthoquinone sulfonic acid chloride and phenol-formaldehyde resins as described in U.S. Pat. Nos. 3,046,120 and 3,188,210. Other known o-naphthoquinone diazide compounds that can be used in the present invention include JP-A-47-5303 and JP-A-48-
No. 63802, No. 63803, No. 96575,
No. 49-38701, No. 13354 (1973), Special Publication No. 41-1973
Publications such as No. 11222, No. 45-9610, and No. 17481, U.S. Patent No. 2797213, U.S. Patent No. 3454400
No. 3544323, No. 3573917, No. 3573917, No. 3544323, No. 3573917, No.
No. 3674495, No. 3785825, British Patent No. 1227602
No. 1251345, No. 1267005, No. 1267005, No. 1251345, No. 1267005, No.
No. 1329888, No. 1330932, German Patent No. 854890
Examples include those listed in each specification, such as No. The amount of o-quinonediazide compounds in the photosensitive composition of the present invention is preferably 10 to 50% by weight in total of the known compounds and the compounds used in the present invention.
It is 20-40% by weight. In the composition of the present invention, phenol formaldehyde resin, cresol formaldehyde resin,
Phenol-modified xylene resin, polyhydroxystyrene, polyhalogenated hydroxystyrene, etc.
A known alkali-soluble polymer compound can be included. Such alkali-soluble polymer compound is used in an amount of 90% by weight or less of the total composition. The composition of the present invention may contain a cyclic acid anhydride to increase sensitivity, a print-out agent to obtain a visible image immediately after exposure, and a dye or other filler as an image coloring agent. Examples of the cyclic acid anhydride include phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, 3,6-endooxy- ^Δ4 -tetrahydrophthalic anhydride, and tetrachloro as described in US Pat. No. 4,115,128. Phthalic anhydride, maleic anhydride, chloromaleic anhydride, α-phenyl maleic anhydride,
Examples include succinic anhydride and pyromellitic acid. By containing these cyclic acid anhydrides in an amount of 1 to 15% by weight based on the total composition, sensitivity can be increased up to three times. Typical print-out agents for obtaining a visible image immediately after exposure include a combination of a photosensitive compound that releases an acid upon exposure and an organic dye that can form a salt. Specifically, the combination of o-naphthoquinonediazide-4-sulfonic acid halide and a salt-forming organic dye described in JP-A-50-36209 and JP-A-53-8128, and JP-A-53-8128. Combinations of trihalomethyl compounds and salt-forming organic dyes described in JP-A No. 36223 and JP-A-54-74728 can be mentioned. In addition to the above-mentioned salt-forming organic dyes, other dyes can also be used as image coloring agents. Suitable dyes include oil-soluble dyes and basic dyes, including salt-forming organic dyes. Specifically, oil yellow #101, oil yellow #130, oil pink #312, oil green BG, oil blue BOS, oil blue #603, oil black.
BY, Oil Black BS, Oil Black T-
505 (manufactured by Orient Chemical Industry Co., Ltd.), Crystal Violet (CI 42555), Methyl Violet (CI42535), Rhodamine B (CI45170B),
Examples include malachite green (CI 42000) and methylene blue (CI 52015). The composition of the present invention is applied onto a 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, and ethyl acetate, and these solvents can be used alone or in combination. do. and,
The concentration (solid content) in the above components is 2 to 50% by weight. Further, although the coating amount varies depending on the application, for example, for photosensitive planographic printing plates, it is generally preferable to have a solid content of 0.5 to 3.0 g/m ² . As the coating amount decreases, the photosensitivity increases, but the physical properties of the photosensitive film deteriorate. When producing a lithographic printing plate using the photosensitive composition of the present invention, the support may be a hydrophilized aluminum plate, such as a silicate-treated aluminum plate, an anodized aluminum plate, a grained aluminum plate, or a silicate plate. There is a coated aluminum plate, as well as zinc plate, stainless steel plate,
Examples include chromium-treated steel sheets, hydrophilized plastic films, and paper. Examples of developing solutions for the photosensitive composition of the present invention include sodium silicate, potassium silicate, sodium hydroxide, potassium hydroxide, lithium hydroxide, tribasic sodium phosphate, dibasic sodium phosphate, tribasic ammonium phosphate, ammonium diphosphate,
Aqueous solutions of inorganic alkaline agents such as sodium metasilicate, sodium bicarbonate, aqueous ammonia, etc. are suitable, and are added at a concentration of 0.1 to 10% by weight, preferably 0.5 to 5% by weight. Moreover, a surfactant and an organic solvent such as alcohol can be added to the alkaline aqueous solution as necessary. Next, the present invention will be explained in more detail by giving Examples. All percentages in the examples below are by weight unless otherwise specified. Example 1 A 2S aluminum plate with a thickness of 0.24 mm was degreased by immersing it in a 10% aqueous solution of tertiary sodium phosphate kept at 80°C for 3 minutes, grained with a nylon brush, and then etched with sodium aluminate for about 10 seconds. Then, desmut treatment was performed with a 3% aqueous solution of sodium hydrogen sulfate. This aluminum plate was anodized in 20% sulfuric acid at a current density of 2 A/d for 2 minutes to produce an aluminum plate ( ). Apply the following photosensitive liquid [A] to this aluminum plate ().
was coated and dried at 100°C for 2 minutes to prepare a photosensitive lithographic printing plate [A]. Photosensitive liquid [A] Esterified product of 1,2-naphthoquinone-2-diazide-5-sulfonyl chloride and cresol-formaldehyde resin 0.80 g Compound obtained in Synthesis Example 1 0.10 g Cresol-formaldehyde resin 1.9 g Oil-soluble dye ( CI42595) 0.04g 1,2-naphthoquinone-2-diazide-4-sulfonyl chloride 0.02g Methyl cellosolve 20g Methyl ethyl ketone 20g The coating weight of the photosensitive lithographic printing plate [A] is 2.5g/
It was ^m2 . Positive transparent originals of line drawings and halftone dot images were brought into close contact with the photosensitive layer of this photosensitive lithographic printing plate [A], and exposure was carried out from a distance of 70 cm using a 30 ampere carbon arc lamp. When the exposed photosensitive lithographic printing plate [A] was developed by rubbing it with a sponge impregnated with a 4% aqueous sodium metasilicate solution, the photosensitive layer was completely removed from the non-image areas. After washing with water, a 14°Be′ gum arabic solution was applied to the plate surface and buff-dried. After leaving the plate for 3 days, I attached it to the lithographic printing machine and started feeding the paper at the same time as the printing machine started, and when printing, the ink was completely deposited on the image area on the 5th or 6th page, and a good, clean print was obtained. Obtained. Comparative Example 1 A photosensitive solution [B] was prepared using p-n-octylphenol formaldehyde resin instead of "the compound obtained in Synthesis Example 1" in the photosensitive solution [A] of Example 1 in the same manner as in Example 1. The mixture was coated on an aluminum plate (I) to prepare a photosensitive lithographic printing plate [B]. When this photosensitive lithographic printing plate [B] was exposed and developed in the same manner as in Example 1, some of the photosensitive layer remained unevenly in the non-image area. When printed in the same manner as in Example 1, the ink receptivity was comparable to that of photosensitive lithographic printing plate [A], but some non-image areas of the printed matter were smudged. Comparative Example 2 In the photosensitive solution [A] of Example 1, except for “the compound obtained in Synthesis Example 1”, “1,2-naphthoquinone-
A photosensitive solution [C] containing 0.80 g to 0.90 g of "esterified product of 2-diazide-5-sulfonyl chloride and cresol-formaldehyde resin" was applied onto an aluminum plate (I) in the same manner as in Example 1, A photosensitive planographic printing plate [C] was produced. This photosensitive lithographic printing plate [C] was plate-made and printed in the same manner as in Example 1, and the ink was completely deposited on the image area at the 20th to 30th sheet after printing. Comparative Example 3 In the photosensitive solution [A] of Example 1, "p-n-octylphenol formaldehyde resin and 1,2-naphthoquinone-2-diazide-5-sulfonyl" were used instead of "the compound obtained in Synthesis Example 1". A photosensitive solution [D] using "esterified product with chloride" was applied onto an aluminum plate (I) in the same manner as in Example 1 to prepare a photosensitive lithographic printing plate [D]. When this photosensitive lithographic printing plate [D] was exposed and developed in the same manner as in Example 1, a portion of the photosensitive layer remained in the non-image area, resulting in slight unevenness. In addition, in order to obtain the same tone reproducibility as the photosensitive planographic printing plate [A] of Example 1, this photosensitive planographic printing plate [D] has an exposure time of 1.2 times longer than that of the photosensitive planographic printing plate [A]. It required twice the exposure time. Comparative Example 4 In the photosensitive solution [A] of Example 1, "the compound obtained in Synthesis Example 1" was replaced by the compound described in Comparative Example 2 of JP-A-56-1045. Photosensitive liquid [E] using "condensation product of 1,2-naphthoquinone-2-diazido-5-sulfonyl chloride and resorcinol-acetaldehyde resin" and JP-A-1044-1988
The photosensitive solution [F] using the "condensation product of 1,2-naphthoquinone-2-diazide-5-sulfonyl chloride and resorcinol-formaldehyde resin" described in Comparative Example 2 of the publication was prepared as Example 1. Photosensitive lithographic printing plates [E] and [F] were prepared by coating in the same manner. These photosensitive lithographic printing plates [E] and [F]
When plate making and printing were carried out in the same manner as in Example 1, the ink was completely deposited on the image area after 15 to 20 sheets had been printed. Comparative Example 5 The "compound obtained in Synthesis Example 1" in Example 1 is synthesized using equimolar amounts of resorcinol and pn-octylphenol as shown in Synthesis Example 1. Compound [a] was synthesized in the same manner as in Synthesis Example 1 using resorcinol and p-n-octylphenol in a molar ratio of 5:95, and compound [b] was synthesized in the same manner as in Synthesis Example 1 using resorcinol and p-n-octylphenol in a molar ratio of 95:5. Photosensitive liquids [G] and [H] used in place of "compound obtained in Synthesis Example 1" in photosensitive liquid [A] of Example 1
were coated in the same manner as in Example 1 to produce photosensitive lithographic printing plates [G] and [H], respectively. When the photosensitive lithographic printing plate [G] was exposed and developed in the same manner as in Example 1, as in Comparative Example 2, a portion of the photosensitive layer remained unevenly in the non-image area. On the other hand, when the photosensitive lithographic printing plate [H] was exposed and developed in the same manner as in Example 1, no unevenness occurred in the non-image area. However, after 15 to 20 prints, the ink was completely applied to the image area. Example 2 The following photosensitive solution [I] was applied to the aluminum plate (I) of Example 1 and dried at 100°C for 2 minutes to produce a photosensitive lithographic printing plate [I]. Photosensitive liquid [I] Esterified product of 1,2-naphthoquinone-2-diazide-5-sulfonyl chloride and pyrogallol-acetone resin 0.80 g (as described in Example 1 of US Pat. No. 3,635,709) Synthesis example Compound obtained in step 2 0.10g Cresol formaldehyde resin 1.9g Oil-soluble dye (CI 42595) 0.03g Phthalic anhydride 0.2g 2-(p-butoxyphenyl)-4,6-bis(trichloromethyl)-s-triazine 0.02g 1,2-naphthoquinone-2-diazide-4-sulfonyl chloride 0.02g Ethylene dichloride 15g Methyl cellosolve 8g Coating weight of photosensitive planographic print [I] is 2.5g/
It was ^m2 . When this photosensitive lithographic printing plate [I] was exposed and developed in the same manner as in Example 1, the photosensitive layer was completely removed from the non-image areas. Gum printing was performed in the same manner as in Example 1, and from the beginning of printing, 4 to 5
On the second sheet, the ink was completely applied to the image area, and a good print without stains was obtained. Comparative Example 6 In the photosensitive solution [I] of Example 2, a photosensitive solution [J] using m-pentadecylphenol-formaldehyde resin instead of "the compound obtained in Synthesis Example 2" was used in the same manner as in Example 1. A photosensitive lithographic printing plate [J] was prepared by coating an aluminum plate (I) using the following method. When this photosensitive lithographic printing plate [J] was exposed and developed in the same manner as in Example 1, a portion of the photosensitive layer remained unevenly in the non-image area. When printed in the same manner as in Example 1, it exhibited ink receptivity equivalent to that of photosensitive lithographic printing plate [I], but some non-image areas of the printed matter were smudged. Comparative Example 7 In the photosensitive solution [I] of Example 2, except for “the compound obtained in Synthesis Example 2”, “1,2-naphthoquinone-2
- esterified product of diazide-5-sulfonyl chloride and pyrogallol-acetone resin" at 0.80
The photosensitive solution [K], which was reduced in weight from g to 0.90 g, was applied onto an aluminum plate (I) in the same manner as in Example 1 to produce a photosensitive lithographic printing plate [K]. This photosensitive lithographic printing plate [K] was plate-made and printed in the same manner as in Example 1.
The ink was finally completely applied to the image area. Comparative Example 8 In the photosensitive solution [I] of Example 2, "m-pentadienephenol formaldehyde resin and 1,2-naphthoquinone-2-diazide-5-sulfonyl chloride" were used instead of "the compound obtained in Synthesis Example 2". A photosensitive liquid [L] using the esterified product of 1 was applied onto an aluminum plate (I) in the same manner as in Example 1 to produce a photosensitive lithographic printing plate [L]. When this photosensitive lithographic printing plate [L] was exposed and developed in the same manner as in Example 1, a portion of the photosensitive layer remained in the non-image area, resulting in slight unevenness. In addition, in order to obtain the same tone reproducibility as the photosensitive planographic printing plate [I] of Example 2, this photosensitive planographic printing plate [L] has an exposure time that is 1.2 times longer than that of the photosensitive planographic printing plate [I]. required an exposure time of

Claims (1)

[Scope of Claims] 1. A photosensitive composition comprising a condensation product of a sulfonyl halide of o-quinonediazide and a polymer compound having a structure represented by the following general formula (). (In the formula, R ₁ and R ₂ are each a hydrogen atom or a carbon number 1
~4 lower alkyl groups, R ₃ is an alkyl group having 4 to 15 carbon atoms or a cycloalkyl group having 4 to 15 carbon atoms, R ₄ and R ₅ are each a hydrogen atom, lower alkyl having 1 to 3 carbon atoms represents a group or a halogen atom, x is
Shows 10-90 mol%. )