JPS6026125B2 - photosensitizer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a photosensitizer with high sensitivity and excellent storage stability.

Many photosensitizers have been known that generate radicals when irradiated with ultraviolet light and can act as polymerization initiators for radically polymerizable compounds with ethylenically unsaturated bonds. Penzoin sensitizers such as methyl ether, benzoin ethyl ether, benzoin isopropyl ether and benzoin, and aromatic ketone sensitizers such as benzophenone and Michler's ketone are well known.

However, when these compounds are used as photosensitizers in photosensitive coating compositions, benzoine-based sensitizers have excellent sensitivity but may not have sufficient storage stability, and aromatic ketone-based sensitizers Although sensitizers have excellent storage stability, they have the problem of poor sensitivity.

As a result of intensive studies to solve these problems, the present inventors found that by combining bis(dialkylamino)penzophenone and a specific aromatic carbonyl compound,
The present invention was achieved by discovering that a photosensitizer with dramatically increased sensitivity and excellent storage stability can be obtained compared to when each of these is used alone.

That is, the present invention is a photosensitizer comprising bis(dialkylamino)penzophenone and at least one aromatic carbonyl compound represented by the following general formula (1).

(However, Ar is a substituted or unsubstituted aromatic nucleus, × is -
NR- or S, R represents a lower alkyl group or an acyl group. ) In formula (1), Ar is a substituted or unsubstituted aromatic nucleus, and a substituted aromatic nucleus means that the hydrogen atom of the aromatic nucleus is a lower alkyl group, halogen, hydroxyl group, alkoxy group, carpoxyl group, alkoxycarbonyl group, Refers to those substituted with cyano groups, nitro groups, etc.

Bis(dialkylamino)penzophenone, which is a component of the present invention, includes 4,4'-bis(dimethylamino)
Penzophenone [Michler's ketone] 4,4′-bis (
Examples include diethylamino)penzophenone and 4,4-bis(diprobilami/)penzophenone.

Further, as the compound represented by the general formula (1),
Examples include, but are not limited to, 9-acridone, thioxanthone, 2-chlorothioxanthone, and N-methyl-9-acridone. The mixing ratio of bis(dialkylamino)penzophenone and the compound represented by the general formula (1) is 1:10 to 10:1 by weight.
, preferably in the range of 1:5 to 5:1.

The unexpectedly high sensitivity obtained by the photosensitizer system consisting of a combination of bis(dialkylamino)penzophenone and an aromatic carbonyl compound similar to the above general formula (1) is because bis(dialkylamino)penzophenone It has a large absorption intensity for ultraviolet rays, efficiently absorbs the irradiated ultraviolet rays, and bis(dialkylamino)penzophenone which is excited by absorbing the ultraviolet rays and the general formula (1)
This is thought to be because the aromatic carbonyl compound represented by the formula forms a molecular compound in an excited state, and this excited molecular compound efficiently generates radicals.

The photosensitizer system of the present invention exhibits an excellent photosensitizing effect through the mechanism described above, and therefore contains one or more radically polymerizable ethylenically unsaturated bond-containing monomers, prepolymers, and polymers. It exhibits particularly excellent effects when used as a photosensitizer component in a thin-film photosensitive coating composition.

Thin film property here means that the film thickness of the photosensitive film is 0.1 mm or more.
It means 50 Buddhas. The radically polymerizable ethylenically unsaturated bond-containing monomers, prepolymers, and polymers that are essential constituents of the thin-film photosensitive coating composition include known compounds having an acroyl group or methacroyl group with a boiling point of 10 or more. Either is fine, and a typical example is given below.

'11 Acrylic acid or methacrylic acid ester of the following alcohols.

Methanol, ethanol, pro/enol, hexanol, octanol, cyclohexanol, ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol,
Glycerin, trimethylolpropane, bentaerythritol, etc.

(2) Reaction products of the following amines or carboxylic acids with glycidyl acrylate or glycidyl methacrylate.

Methylamine, ethylamine, butylamine, benzylamine, ethylenediamine, diethylenetriamine, hexamethylenediamine, P-xylylenediamine, m-xylylenediamine, ethanolamine, dimethylamine, diethylamine, diethanolamine, aniline, etc.

Acetic acid, propionic acid, benzoic acid, acrylic acid, methacrylic acid, succinic acid, maleic acid, phthalic acid, tartaric acid, citric acid.

Glue Amide derivatives as shown below.

Acrylamide, methacrylamide, N-methylolacrylamide, methylenepisacrylamide, diacetone acrylamide, etc.

{Reaction product of 4' epoxy compound and acrylic acid or methacrylic acid.

{5} A reaction product of an isocyanate-containing compound and 8-hydroxyethyl acrylate or 8-hydroxyethyl methacrylate.

One or more of these compounds can be used as a constituent component, and if necessary, it is also possible to add an organic polymer compound that can be mixed with these compounds.

Examples of such organic polymer compounds include the following polymers and copolymers.

{1} Acrylic acid ester, methacrylic acid ester,
Polymers of acrylonitrile, such as polyethyl acrylate, polymethyl methacrylate, polybutyl acrylate, etc., and copolymers thereof.

'21 Unvulcanized rubber, such as polybutadiene, polyisobutylene, polychloroprene, styrene-butadiene rubber, etc.

'3} Pinyl polymers, such as polypynylacetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl chloride, and copolymers thereof.

■ Polyethers, such as polyethylene oxide.

■ Polyesters, such as phthalic acid, isophthalic acid,
Maleic acid, adipic acid, etc. and ethylene glycol, 1,
Reaction products such as 4-butanediol, 1,6-hexanediol, neobentyl glycol, etc.

'6} Polyurethane, such as toluene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, etc. and 1,4-butanediol, 1,6-hexanediol, '4' polyether polyol,
Reaction product with polyester polyol etc. obtained in {5}.

'7} Epoxy resin (8' Polyamide thin film photosensitive coating composition contains 10 to 98% by weight of one or more of the radically polymerizable ethylenically unsaturated bond-containing monomers, prepolymers, and polymers). If necessary, 1 to 8 parts by weight of an organic polymer compound is added, and the weight ratio of bis(dialkylamino)penzophenone to the aromatic carbonyl compound represented by the general formula (1) is 1:10 to 10: 1 preferably < is 1:5 to 5; 1
It can be obtained by adding 0.5 to 1 part by weight of the mixture.

In addition to the above-mentioned components, additives such as dyes and polymerization inhibitors may be added as necessary.

As a preferred application example of using the combination of the bis(dialkylamino)penzophenone of the present invention and the aromatic carbonyl compound represented by the general formula (1) as a photosensitizer component, the thin film photosensitivity obtained as described above is A photosensitive printing plate for lithography that does not require dampening water can be obtained by providing a silicone rubber layer with a thickness of 0.5 to 50 m thick on the upper or lower layer of the coating. The silicone rubber used here is obtained by sparsely crosslinking a linear diorganopolysiloxane (preferably dimethylpolysiloxane) having an appropriate molecular weight.

This crosslinking density can be expressed by the R/Si ratio in the figure below, and is 1.90 to 2.10 for useful silicone rubbers. A typical silicone rubber has the following repeating units. Here, n is an integer of 2 or more.

R is an alkyl group having 1 to 10 carbon atoms, an alkyl group, or a vinyl group.

Such silicone rubbers can be sparsely sealed by adding organic peroxides, but silicone rubbers that perform condensation type crosslinking (RTV, LT) as shown below
A more preferable silicone rubber film can be obtained by using V-type silicone rubber). In the case of a condensed type, a diorganopolysiloxane chain in which a portion of R is substituted with H' is also used, but crosslinking is usually achieved by condensation of terminal groups as described below. Here, R has the same meaning as R explained above, R' is a monovalent alkyl such as methyl or ethyl, and Ac is an acetyl group.

The present invention will be explained in detail below with reference to Examples.

Example 1 A photosensitive coating composition having the following composition was applied onto a tin plate using an applicator to a thickness of 9 microns.

'a'"Teisan Resin SBIIIC-1" (manufactured by Teikoku Kagaku Sangyo Co., Ltd.) Solid content of copolymer of butyl acrylate and acrylonitrile 6% by weight (b} N
,N,N',N'-tetrakis-2-hydroxy-3-methacroyloxypropylethylenediamine (4'1 molar ratio reaction product of glycidyl methacrylate and ethylenediamine) 3% by weight'c- Photosensitizer
4% by weight This film was irradiated with light from a pink W high-pressure mercury lamp from a distance of 1 skin in the air, and the sensitivity was defined as the number of seconds until the film lost its tackiness.

The results are shown in Table 1.

If a photosensitizer is used alone, enter 100% in the ratio column.
When mixed, the ratio of each to the total photosensitizer is described in %. As is clear from Table 1, when 4,4'-bis(dimethylaminobenzophenone or aromatic carbonyl compound) is used alone, the sensitivity is low (it takes a long time for the stickiness to disappear). , 4,4'-bis(dimethylamino)penzophenone and an aromatic carbonyl compound are used in combination, the sensitivity is high.

Claims (1)

[Scope of Claims] 1. A photosensitizer comprising bis(dialkylamino)benzophenone and at least one aromatic carbonyl compound represented by the following general formula (I). ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (However, Ar is a substituted or unsubstituted aromatic nucleus, X is -NR- or S, and R is H, a lower alkyl group, or an acyl group.