JPS5988736A - Photosensitive composition - Google Patents

Abstract

PURPOSE:To obtain a photosensitive composition giving an image with high ink receptivity by adding a specified high molecular compound and an o-naphthoquinone diazide compound. CONSTITUTION:A high molecular compound having a structure represented by formula I or II (where each of R1, R2 and R3 is H or 1-4C alkyl; R4 is 4-15C alkyl or 4-15C cycloalkyl; each of R5 and R6 is H, 1-3C alkyl or halogen; and (x) is 10-90mol%) and an o-naphthoquinone diazide compound such as the ester of 1,2-naphthoquinone-2-diazido-5-sulfonic acid chloride with pyrogallol-acetone resin as a photosensitive compound are added to obtain a photosensitive composition. The high molecular compound has high sensitivity owing to a constituent component represented by formula III, and it dissolves in an aqueous alkali soln. as a developer owing to a constituent component represented by formula IV or V. The photosensitive composition gives an image with high ink receptivity, remains scarcely on a non-image part after development, and causes hardly scumming.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a groove photosensitive composition suitable for producing lithographic printing plates. More specifically, the present invention relates to a photosensitive composition comprising an 0-naphthoquinone diazide compound and an alkali-soluble polymer compound. Lithographic printing is a printing method that skillfully takes advantage of the property that water and oil do not mix with each other. The ability to accept oil-based ink is required, and because of these characteristics, the stronger the ink, the easier it is to produce high-quality printed matter. Conventionally, in order to improve this property, developing ink is applied to the image surface in the plate-making process after exposure to improve ink receptivity ( However, this method complicated the plate-making process and involved coating with developing ink, which took time and effort.

For this purpose, there is a method of adding a substituted phenol albut resin, especially a tertiary butylphenol formaldehyde resin, to a photosensitive composition containing an 0-quinonediazide compound! It was disclosed in Japanese Patent Publication No. 50-125806. The addition of tertiary leaf thylphenol (pol-15 al-15)' resin did improve the oil-sensitivity of the image area compared to the case without the additive, but on the other hand, the photosensitive composition remained in the non-image area after development. Part of the object tends to remain, especially when developing by soaking a developing solution into absorbent cotton or a sponge and rubbing the printing plate, the photosensitive composition may remain partially in the non-image area, which may spoil the appearance. Without,
Scumming often occurred.

Accordingly, an object of the present invention is to provide a photosensitive composition that provides images with high ink receptivity.

Another object of the present invention is to provide a photosensitive composition that does not leave any residual photosensitive composition in non-image areas after development and is free from scumming.

As a result of various studies to achieve the above object, the present inventors have discovered that a polymer compound having a structure represented by the following general formula (1) and general formula (11) and a photosensitive composition. The present invention has been achieved by discovering that a photosensitive composition characterized by containing a 0-naphthoquinonediazide compound can achieve the above object.

(In the formula, R1, R2, R3 are each a hydrogen atom or a lower alkyl group having 1 to 4 carbon atoms, R4 is an alkyl group having 4 to 15 carbon atoms or a cycloalkyl group having 4 to 15 carbon atoms, R5
, R6 each represents a hydrogen atom, a lower alkyl group having 1 to 6 carbon atoms, or a halogen atom, and X represents a molar ratio of 10 to 90. ) The polymer compound in the present invention has a structure represented by general formula (11 to general formula (n>), and is characterized by being soluble in a developer (alkaline water). In (U) R1,f(
2°R3 is each 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. R4 is an alkyl group having 4 to 15 carbon atoms or a cycloalkyl group having 4 to 15 carbon atoms, and as a preferable example, tertiary
Butyl group, tertiary octyl group, normal octyl group, normal hexyl group, -? Examples include tadecyl group.

R5 and R6 are each a hydrogen atom, a lower alkyl group having 1 to 4 carbon atoms, or a halogen atom, preferably a methyl group, an ethyl group, a chlorine atom, or a hydrogen atom, but more preferably a hydrogen atom. . X has a molar ratio of 10 to 90%, preferably 20 to 70%.

In order to effectively serve the purpose of the present invention, the molecular weight of the polymer compound in the present invention is approximately 500.
~io, oooO can be used, but preferably about 800 to 4,000.

The polymer compounds represented by general formula (1) and general formula (II) in the present invention are synthesized as follows.

That is, catechols such as catechol, 4-methylcatechol, and 4-tert-butylcatechol (in the case of general formula (I)), hydroquinones such as hydroquinone, 2-methylhydroquinone, and 2-ethylhydroquinone (in the case of general formula (II)), etc. ) and phenols such as 4-tert-butylphenol, 4-n-octylphenol, and 4-tertatecylphenol in a molar ratio of 1:9 to 9:1. Aldehydes and ketones such as formaldehyde, acetone, acetaldehyde, and methyl ethyl ketone can be prepared either alone or dissolved in a solvent such as alcohol at pH, using an acid such as hydrochloric acid, oxalic acid, or an alkali such as sodium hydroxide or aqueous ammonia as a catalyst to produce aldehydes or ketones. The desired polymer compound can be obtained by condensing the same compound using 0.85 to 10 mole parts per 1 mole part of the mixture of polyhydric phenols and phenols. At this time, polyhydric phenols, phenols, and aldehyde V/ketones can be freely combined with each other, and two or more of them may be mixed for co-condensation.

Next, a typical synthesis example of a polymer compound represented by the general formula m or (IJ) in the present invention will be shown.

Synthesis Example 1 - Catechol 55j? , P-t-butylphenol 225
,! 9 was dissolved in 1,4-dioxane 5QQme, and 162 g of formalin No. 37 was added thereto with stirring. Furthermore, 1 ml of 5N hydrochloric acid was added as a catalyst.

The mixture was gently heated to reflux while being careful not to cause bumping. After 5 hours, the reaction mixture was poured into a cold water filter, and the precipitated pale yellow resin was separated and dried, yielding 260.9. The molecular weight of this 4bJ fat was determined to be approximately 2,000 using a light scattering method.

Synthesis example 2゜110 g of highzoquinone and 206 g of p-n-octylphenol were dissolved in 1.4-dioxane 50011-,
To this was added 162 ml of formalin 67 with stirring. Furthermore, 5N hydrochloric acid (1 ml) was added as a catalyst, and the mixture was gently heated to reflux while being careful not to cause bumping. 5
After a period of time, the reaction mixture was poured into cold water 61, and the precipitated pale yellow resin was separated and dried to obtain 275 g. The molecular weight of this resin was measured using a light scattering method and was approximately 19.
It was 00.

Synthesis Example 6゜4-Methylcatechol 999, ρ-t-butylphenol 180,! i' to 1,4-dioxa 7500mA
! 67% formalin 162I was added thereto with stirring. Furthermore, 5N base acid 1 hemp 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 31, and the precipitated Tankosha resin was dried to obtain a bundle of 278.9 f. The molecular weight of this resin was determined to be approximately 2,600 using a light scattering method.

In the present invention, the amount of the polymer compound in the photosensitive composition is 0.1 to 60% by weight, more preferably 0.5 to 2% by weight.
It has a weight of 0, most has a weight of 0.5 to 2.

The O-naphthoquinone diazide compound used in the present invention is an ester of 1,2-naphthoquinone-2-diazide-5-sulfonic acid chloride and pyrogallol-acetone resin described in Japanese Patent Publication No. 43-28403. It is most preferable that Other suitable orthoquinonediazide compounds include U.S. Pat.
No. 120 and No. 3.188.210+! There are esters of 1,2-naphthoquinone-2-diazide-5-sulfonic acid chloride r and phenol-formaldehyde resins described in the specification. Other useful o −
Naphthoquinone diazide compounds are reported and known in numerous patents. For example, JP-A No. 47-53
No. 03, No. 48-63802 of the same town, No. 48-6380 of the same town
No. 3, No. 48-96575 of the same town, No. 49-38701 of the same town
No. 48-13354, Special Publication No. 11222-1973
No. 45-9610, U.S. Patent No. 49-17481, U.S. Patent No. 2.797,213, U.S. Patent No. 6.454
, No. 400, No. 3,544,323, No. 6,57
6.917, same No. 3, . No. 674,495, same No. 5.
No. 785.825, British Patent No. 1.227,602;
Same No. 1.251.345 No. 1.267.005,
Examples include those described in German Patent No. 1.329.888, German Patent No. 1.330,932, and German Patent No. 854.890.

The amount of O-naphthoquinonediazide compound in the photosensitive composition of the present invention is 10 to 50% by weight, more preferably 2% by weight.
0 to 40 weight.

In addition to the polymer compound of the present invention, the composition of the present invention includes phenol formaldehyde resin, cresol formaldehyde f4fR fat, phenol-modified xylene m fat,
Known alkali-soluble polymer compounds such as yl#lyhydroxystyrene and polyhalogenated hydroxystyrene can be contained. The alkali-soluble polymer compound is used in an amount of less than 70% by weight 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 its filler as an image fixing agent. reactor. As a cyclic acid anhydride, US Pat. No. 4.115.
As described in No. 128 Mei IYl111-, phthalic anhydride, tetrahydrophthalic anhydride, hexahyphthalic anhydride ME, 3,6-oxy-Δ-tetrahydrophthalic anhydride, tetrachlorophthalic anhydride, maleic anhydride. acids, chloromaleic anhydride, α-phenylmaleic anhydride, succinic anhydride, pyromellitic acid, and the like. By including these cyclic acid anhydrides in an amount of 1 to 15% by weight in the total composition, the sensitivity can be increased up to about 6 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 r and a salt-forming organic dye described in JP-A-50-36209 and JP-A-56-8128, and JP-A-53 Combinations of trihalomethyl compounds and salt-forming organic dyes described in Japanese Patent Application Laid-open No. 36223 and Japanese Patent Application Laid-Open No. 74728/1986 can be mentioned. In addition to the above-mentioned background-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 #10
1. Oil yellow #130. Oil pink #312.
Oil Green BG, Oil Blue BO8, Oil Blue #603, Oil Black BY, Oil Black BS
, Oil Black T-505 (manufactured by Orient Chemical Industry Co., Ltd.), Crystal Violet (CI42)
535), Methyl Violet (CI42535), Rhodamine B (CI45170B), Malachite Green (CI4') [100), Methylene Pur=(CI520)
15) I can name l:c.

The composition of the present invention is applied onto a support after being dissolved in a solvent that dissolves each of the above components. The solvent used here is
Examples 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 are used alone or in combination. The concentration If (solid content) in the above components is 2 to 50% by weight. In addition, the coating amount is generally 0.5 to 3.0 as solid content.
g/d is preferred. As the coating amount decreases, the photosensitivity improves, 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 aluminum plate. 1! There is a plated aluminum plate, and other plated lead plate,
Stainless steel plates, chromium-treated steel plates, hydrophilized plastic films and paper can be used.

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, diphosphoric acid, Aqueous solutions of inorganic alkaline agents such as ammonium chloride, sodium metasilicate, sodium bicarbonate, aqueous ammonia, etc. are suitable, their concentration being 01-10% by weight,
It is preferably added in an amount of 0.5 to 5% by weight.

Furthermore, a buttock activator or an organic solvent such as alcohol can be added to the alkaline aqueous solution if necessary.

Next, the present invention will be explained in more detail by giving examples. ? τOh, is the percentage that can be applied to the following example different from the other 1? t], all heavy (-w section).

Example 1 A 28 aluminum rod with a thickness of 0.24 mm was immersed for 3 minutes in a 10% aqueous solution of sodium tertiary acid maintained at 8,000 to degrease it, and then grained with an iron brush. The film was etched for about 10 seconds, and then desmutted with a 6-part aqueous solution of sodium hydrogen sulfate. In this aluminum plate 'aj 20% sulfur σΦ, the current density is 2A/
Ctrt? An aluminum plate (1) was prepared by performing Il ita oxidation for 2 minutes at I.
), then apply σ)lit'(, light, ru [A], 1[1
Dry at 0°C for 2 minutes and prepare a 7d4 photolithographic printing plate [A].

Photosensitive solution [A] 1. Esterified product of 2-naphthoquinone-2-diazide-5-sulfonylchloride r and Talesol-Formaldehy YmT fat 0.90.9 Cresol-Formaldehyde Kage 1.9 9 Synthesis example Compound obtained in 1
[3,05g oil-soluble dye (CI, 42595
) 0.0351.2-naphthoquinone-
2-diazidi-4-sulfonylchloride)-''
0.02,9 methyl cellosolve
20.9 Methyl ethyl ketone
20g Next, as a comparative example, a photosensitive solution [A] in which pt-butylphenol-formaldehy V resin was used instead of the compound obtained in Synthesis Example 1 in the photosensitive solution CB) was added to an aluminum plate (II vc photosensitive solution [A]). ] to prepare a photosensitive planographic printing plate [B). In addition, as another comparative example, in photosensitive liquid [A], Synthesis Example 1
Photosensitive liquid with cresol formaldehyde resin reduced from 1.9g to 1.95.9g by excluding the compound obtained in [0]
was applied in the same manner as the photosensitive liquid [A], and a photosensitive planographic printing plate [C
] was created. The coating weight of the photosensitive lithographic printing plates [A], [B] and [C] after drying was all 2.09/-. Positive transparent originals of line drawings and halftone dot images were brought into close contact with the photosensitive layers of these photosensitive lithographic printing plates, and exposure was carried out from a distance of 70 cm using a 60 annia carbon arc lamp.

Exposed prestige lithographic printing plates rA], [B] and [0
] It was developed by rubbing with a sponge impregnated with a 6-functional aqueous solution of sodium metasilicate (nase hydrate). The photosensitive lithographic printing plates [A"l and [C] can be developed quickly and the non-image area I
C is mostly a photosensitive composition...Shira/I (a beautiful printing plate was obtained. Comparative example photosensitive lithographic printing plate CB) is
Although the image could be developed quickly, some of the photosensitive composition remained in the non-image area, and the unevenness did not disappear even after the image was developed again. After washing with water, each lithographic printing plate was heated at 14°B.
/An aqueous gum arabic solution was applied to the printing plate and puffed. After placing the filter plate, it was attached to the lithographic printing machine, and paper feeding was started at the same time as the printing machine started, and printing was performed. The lithographic printing plate [A] and [
B], the ink completely adhered to the image area on the 5th to 6th sheet, but in the lithographic printing plate [0] according to the comparative example, the ink completely adhered on the 30th sheet. Versions [A) and [0]
The printed matter was free from stains, whereas the lithographic printing plate [B] according to the comparative example had some stains.

Example 2 The following photosensitive liquid CD was coated on the aluminum plate of Example 1 in the same manner as in Example 1 to prepare a photosensitive lithographic printing plate of the present invention [D].
] was created.

Photosensitive liquid [D] Esterified product of 1.2-naphthoquinone-2-diadi V-5-sulfonyl chloride 9 and pyrogallol-acetone resin 080 g (U.S. Patent No. 3.635,7
09 Specification Example 1) Compound obtained in Synthesis Example 2 0.1 (L
9 Cresol-formaldehyde resin 1.7,
9 Oil-soluble dye (GI 42595) Phthalic anhydride 0.20,
92-(p-butoxyphenyl)-4,6-bis(trichloromethyl)-I-triazine
0. Oi ethylene dichloride)' 15.9 methyl cellosolve 8 gNext, as a comparative example, a photosensitive solution [D] was prepared using p-n-octyl-formaldehy V resin instead of the compound obtained in Synthesis Example 2. E] was applied in the same manner as the photosensitive liquid [A] to prepare a photosensitive lithographic printing plate [1'E]. As another comparative example, photosensitive liquid [D] was prepared by removing the proboscis of the compound injected in Synthesis Example 2 and adding 17.9 to 18 g of cresol-formaldehy V resin. An electrophotographic lithographic printing plate [F] was prepared. J”+t&
Photolithographic printing plate [D].

[E'3 and [F] coated molds (tubes)'' after drying were all 2.2β/rr? These photosensitive lithographic printing plates were exposed and developed in the same manner as in Example 1. Photosensitivity The printing plates [D] and [F] can be developed quickly, and almost no photosensitive composition remains in the non-image areas. [E]1: Although it was developed smoothly, the photosensitive composition remained in the non-image area in an uneven manner, and the unevenness did not disappear even after developing it again.;'('Jl It After washing the lithographic printing plate with water, it was heated to 14°B.
C' An aqueous solution of gum arabic was applied to the printing plate and buffed and V-dried. On the 6th, the plate rk was installed on the lithographic printing machine, the pressure was started at the same time as the printing machine started, and printing was carried out, lithographic printing plate C
D] and [E), the ink was completely applied to the image area on the 5th to 6th sheet, but for the comparative lithographic printing plate [F] made by I911, the ink was finally inked on the 20th sheet. D] and CF
In contrast, the lithographic printing plate [E] according to the comparative example had stains in some parts, whereas the plate obtained in the case of 'l' had a lot of stains.

Representative Patent Attorney (8107) Takashi Sasaki RFT (
and 6 others)

Claims (1)

[Scope of Claims] (11) A polymer compound having a structure represented by the following general formula (1) to general formula (11) and O as a photosensitive composition
- a naphthoquinone diazide compound. (In the formula, R,, R2, R3 are each hydrogen JJ?f 51M
, a lower alkyl group having 1 to 4 carbon atoms, R4 is a lower alkyl group having 4 to 4 carbon atoms
15 alkyl group or cycloalkyl group having 4 to 15 carbon atoms, R5 and R6 each represent a hydrogen atom, a lower alkyl group having 1 to 6 carbon atoms, or a halogen atom, and X is 10 to 90
Indicates the mole officer. )