JPH0545877A - Photopolymerizable composition - Google Patents

Abstract

PURPOSE:To obtain high sensitivity and to prevent stains due to dye when the compsn. is used for plate-making printing by incorporating a salt of anion dye and cation latex containing quaternary nitrogen atom or quaternary phosphorus atom. CONSTITUTION:The compsn. contains a salt of anion dye and a cation latex containing quaternary nitrogen atom or quaternary phosphorus atom. The salt of anion dye and a cation latex containing quaternary nitrogen atom or quaternary phosphorus atom is produced from a cation latex polymer containing quaternary nitrogen atom or quaternary phosphorus atom and from a dye containing counteranion. As for the anion dye, well-known dyes can be used, and preferably, dyes having counteranion groups for the cation latex, for example, -SO3<->H<+>, -COO<->H<+> or -O<->H<+>, are used. Moreover, although the anion dye acts as a photopolymn. initiator, another photopolymn. initiator can be used together with the anion dye.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a photopolymerizable composition,
Particularly, it relates to a photopolymerizable composition which can be used for a plate making printing plate with high sensitivity.

[0002]

BACKGROUND OF THE INVENTION Conventionally, as a photopolymerizable composition used for a plate making printing plate, one containing a binder resin, an ethylenically unsaturated compound and a photopolymerization initiator has been used, and particularly, a quaternary nitrogen. A photopolymerizable composition containing a cationic latex having an atom or a quaternary phosphorus atom is disclosed in Japanese Patent Publication No. 2-15056. However, in the case of the photopolymerizable composition as described above, the polymerization efficiency is low, and therefore it is insufficient in particular in terms of sensitivity for use in a plate making printing plate or the like.

Further, in these plate-making printing plates, the dye is adsorbed on the substrate (support) and causes stains.
It has been desired to improve this stain.

An object of the present invention is to provide a photopolymerizable composition which has high sensitivity and does not cause stains due to dyes when used in a plate-making printing plate.

[0005]

The present inventors have conducted extensive studies in view of the above problems, and as a result, the above object of the present invention is to provide a salt of a cationic latex having a quaternary nitrogen atom or a quaternary phosphorus atom with an anionic dye. It has been found to be achieved by providing a photopolymerizable composition containing. The present invention will be described in more detail below.

The salt of a cation latex containing a quaternary nitrogen atom or a quaternary phosphorus atom and an anionic dye used in the present invention is a dye having a cationic latex polymer containing a quaternary nitrogen atom or a quaternary phosphorus atom and a counter anion. It is formed from and.

The quaternary nitrogen-containing cationic latex polymer used in the present invention is disclosed in JP-B-2-47738, column 3, line 33 to column 13, line 14 and line 31, line 31. Can be mentioned.

As the anionic dye, those already known can be used. As such, a dye for example, -SO ₃ having a counter anion group of cationic latex ^- H ^+, -COO ^- H ⁺ or -O ^- dye having an H ⁺ are preferred. These anionic dyes are described in the following materials. (A) "Chemistry of synthetic dyes" (Konoki, Kuroki; Maki Shobo) (b) "Review Synthetic dyes" (Horiguchi: Sankyo Publishing) (c) "Photosensitive dyes" (Ogata: Sankaido) (d) "Photosensitizing dyes and their applications"(Ogata; Kawade Shobo) (e) "Introduction to photographic dyes"(Kimura; Industrial book KK) (f) "Recent advances in cyanine dye synthesis"(Hiba; Organic synthetic chemistry) (Journal of the Society, 32, 971-988) (G) "Recent advances in the use of cyanine dyes and research on physical properties" (Hiba, Journal of the Photographic Society of Japan, 38, 5, 42)
(Pp. 1-436)

In the present invention, the anionic dye acts as a photopolymerization initiator, but it can be used in combination with other photopolymerization initiators.

The cation latex containing a quaternary nitrogen atom or quaternary phosphorus atom and a salt of an anionic dye used in the present invention have a solid content of 20 to 90 in the polymerizable composition of the present invention.
It is preferably contained in an amount of 40% by weight, particularly 40 to 70% by weight.

Specific examples of synthesizing a salt of the above cation latex containing a quaternary nitrogen atom or a quaternary phosphorus atom and an anionic dye are shown below.

Synthesis Example 1 [Synthesis of Salt-1 of Cationic Latex Containing Quaternary Nitrogen Atom and Anionic Dye] Dispersion of 10% solid content of quaternary nitrogen-containing cationic latex polymer represented by the following formula (I): The precipitate obtained by mixing water and an aqueous solution of the dye represented by the following formula (II) was collected by suction filtration and washed with water to obtain the desired product.

[0013]

[Chemical 1]

Synthesis Example 2 [Synthesis of Salt-2 of Quaternary Nitrogen Atom-Containing Cationic Latex and Anionic Dye] A quaternary nitrogen atom-containing cationic latex polymer represented by the formula (I) of Synthesis Example 1 is described below. According to the method of Synthesis Example 1 except that the dye represented by the formula (III) or the dye represented by the formula (II) is changed to the dye represented by the following formula (IV), a quaternary nitrogen atom-containing cationic latex and an anion are used. Salt-2 with a sex dye was obtained as a powder.

[0015]

[Chemical 2]

Synthesis Example 3 [Synthesis of Salt-3 of Quaternary Nitrogen Atom-Containing Cationic Latex and Anionic Dye] A quaternary nitrogen atom-containing cationic latex polymer represented by the formula (I) of Synthesis Example 1 is described below. According to the method of Synthesis Example 1 except that the dye represented by the formula (V) or the dye represented by the formula (II) is replaced by the dye represented by the formula (VI), a quaternary nitrogen atom-containing cationic latex and an anion are used. Salt-3 with a sex dye was obtained as a powder.

[0017]

[Chemical 3]

Synthesis Example 4 [Synthesis of Salt-4 of Quaternary Nitrogen Atom-Containing Cationic Latex and Anionic Dye] A quaternary nitrogen atom-containing cationic latex polymer represented by the formula (I) of Synthesis Example 1 is described below. The target product was obtained according to the method of Synthesis Example 1 except that the dye represented by the formula (VII) and the dye represented by the formula (II) were changed to the dye represented by the following formula (VIII).

[0019]

[Chemical 4]

Examples of the photopolymerization initiator that can be used in the present invention include those described in J. Carbonyl compounds, organic sulfur compounds, superfluids, redox compounds, azo and diazo compounds, halogen compounds, photoreducing agents as described in Chapter 5 of "Light Sensitive Systems" by J. Kosar. Examples include dyes. More specific compounds are disclosed in British Patent No. 1,459,563.

That is, the following can be used as the photopolymerization initiator. For example, benzoin methyl ether, benzoin isopropyl ether, benzoin derivatives such as α, α-dimethoxy-α-phenylacetophenone; benzophenone, 2,4-dichlorobenzophenone, methyl o-benzoylbenzoate, 4,4′-bis (dimethylamino) ) Benzophenone, benzophenone derivatives such as 4,4′-bis (diethylamino) benzophenone; thioxanthone derivatives such as 2-chlorothioxanthone and 2-isopropylthioxanthone; anthraquinone derivatives such as 2-chloroanthraquinone and 2-methylanthraquinone; N-methylacryne Acridone derivatives such as don and N-butylacridone; α, α-diethoxyacetophenone; benzyl; fluorenone; xanthone;
Uranyl compounds; halogen compounds and the like.

The photopolymerizable composition of the present invention may contain a binder resin, if desired. As the binder resin, various known polymers can be used. For specific binder details, see US Pat.
072,527, more preferably JP-A-54-
A monomer having an aromatic hydroxyl group, such as N- (4-hydroxyphenyl), as described in Japanese Patent Publication No. 98613.
Copolymers of acrylamide, N- (4-hydroxyphenyl) methacrylamide, o-, m-, or p-hydroxystyrene, o-, m-, or p-hydroxyphenylmethacrylate with other monomers, U.S. Patent No. 4,
Polymers containing hydroxyethyl acrylate units or hydroxyethyl methacrylate units as the main repeating unit as described in 123,276, natural resins such as shellac and rosin, polyvinyl alcohol, U.S. Pat.No. 3,751,257 in Polyamide resin as described, linear polyurethane resin as described in U.S. Pat.No. 3,660,097,
A phthalated resin of polyvinyl alcohol, an epoxy resin condensed from bisphenol A and epichlorohydrin, and celluloses such as cellulose acetate and cellulose acetate phthalate are included.

The photopolymerizable composition of the present invention includes an oil sensitizer,
Additives such as surfactants, sensitizers, stabilizers, thermal polymerization inhibitors, plasticizers, dyes such as dyes and pigments may be contained.

The use of the photopolymerizable composition of the present invention is not particularly limited, but it is preferably used as a plate-making printing plate material, and in particular, it is coated on a support to form a photosensitive layer. Then, it is suitable for use as an image forming material such as a lithographic printing plate and a mask material. When the plate-making printing plate is prepared by applying the photopolymerizable composition according to the present invention, the support used is a metal plate such as aluminum, iron, copper, or an alloy thereof, a paper support, particularly a synthetic paper. (polypropylene,
Polyethylene laminated paper etc.) and plastic supports (especially cellulose acetate, polyethylene terephthalate, polypropylene, polystyrene, vinylidene chloride etc.) can be mentioned. Such a support is preferably surface-treated electrically, chemically and mechanically for the purpose of improving adhesion. Further, it may have an undercoat layer.
Further, in order to control curling and surface slippage, a curl prevention layer or a mat layer may be processed on the surface opposite to the photosensitive layer.

To produce an image-forming material using the photopolymerizable composition according to the present invention, a spin coating method, a brush coating method, a doctor blade coating method or a hopper coating method is typically used. Apply and dry. As a coating solvent, water, acetone, methanol, ethanol, methyl cellosolve, ethyl cellosolve, halogenated hydrocarbon, ethyl acetate, etc. are generally used, and coating is carried out as a solution thereof. Further, in order to control the surface physical properties of the image forming material, a protective layer or a matte layer which is soluble or penetrable in developing water may be provided.

The coating amount of the photosensitive layer due to the photopolymerizable composition according to the present ^{invention, 0.1g / m 2 ~20g / m} 2 range is better, more preferably at 0.5g / m ² ~5g / m ² If it is too thin, the film strength of the photosensitive layer will be insufficient, and if it is too thick, the sensitivity will be lowered and the resolution will be insufficient.

[0027]

The present invention will be described more specifically with reference to the following examples.

Example 1 A recording material was obtained by coating the following photopolymerizable composition on a grained and anodized aluminum plate so that the film thickness after drying would be 3.0 μm.

Photopolymerizable composition Salt of cation latex containing quaternary nitrogen atom and anionic dye-1 45 parts by weight Pentaerythritol triacrylate 40 parts by weight Methyl cellosolve 500 parts by weight

This recording material was irradiated with an argon ion laser at an output of 2.5 W and a beam diameter of 1.25 mm, developed with water, and the irradiation time required for the diameter of the insoluble portion to become 1.00 mm was measured. The irradiation energy was calculated. The results are shown in Table 1.

Example 2 Except that in Example 1, the cation latex containing a quaternary nitrogen atom and an anionic dye salt-1 was changed to a cation latex containing a quaternary nitrogen atom and an anionic dye salt-2.
The same procedure as in Example 1 was performed.

Example 3 In Example 1, the quaternary nitrogen atom-containing cation latex and anionic dye salt-1 were changed to a quaternary nitrogen atom-containing cation latex and anionic dye salt-3, and 2 parts by weight of diisopropylthioxanthone was used. The same procedure as in Example 1 was performed except that the addition was made.

The results of Examples 1, 2 and 3 are shown in Table 1.

[0034]

[Table 1] As is clear from Table 1, the photopolymerizable composition of the present invention has extremely high sensitivity.

Example 4 An aluminum plate having a thickness of 0.3 mm was immersed in a 20% aqueous solution of sodium phosphate for degreasing, electrolytic polishing was carried out, followed by anodization in sulfuric acid, and further treatment with an aqueous solution of sodium metasilicate. It was washed with water and dried.

A sample was obtained by coating this substrate (support) with a photosensitive solution having the following composition so that the film thickness after drying was 3.0 μm.

Photosensitive solution composition Quaternary nitrogen-containing cation latex and salt of anionic dye-4 50 parts by weight trimethylolpropane triacrylate 40 parts by weight Michler's ketone 10 parts by weight Methyl cellosolve 400 parts by weight

A negative film and a Kodak step tablet No. 2 were adhered onto the above sample and idle fin 2000
[2KW metal halide lamp manufactured by Iwasaki Electric Co., Ltd.]
Exposure for 30 seconds and rubbed with a sponge for 1 minute in water at 25 ° C. to remove the unexposed portion to obtain a printing plate.

When this printing plate was printed on a high-quality paper by using a sheet-fed offset printing machine, 30,000 or more good prints without background stains were obtained.

Comparative Example 1 In Example 4, the quaternary nitrogen-containing cation latex and the salt of an anionic dye were changed to -4, and (VI of Synthesis Example 4) was used.
I) a quaternary nitrogen-containing cation latex represented by the formula
When 5 parts by weight and 5 parts by weight of the dye represented by the formula (VIII) were used and the same procedure as in Example 4 was carried out, the blue-violet dye remained on the non-image part of the printing plate, and the printed matter was stained from 20,000 sheets. Occurred.

[0041]

By using a salt of a cationic latex having a quaternary nitrogen atom or a quaternary phosphorus atom and an anionic dye, the initiation efficiency of photopolymerization is improved and a highly sensitive photopolymerizable composition is obtained. Be done. When the photopolymerizable composition is used in a plate-making printing plate, the dye is removed by development without adsorbing to the support (causing stains), and thus a stain-free printed matter can be obtained.

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Claims (1)

[Claims] 1. A photopolymerizable composition comprising a salt of a cationic latex having a quaternary nitrogen atom or a quaternary phosphorus atom and an anionic dye.