JPH0466349B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a highly sensitive photopolymerizable composition. By applying this composition to various substrates, it has a wide range of uses as an image forming material such as printing plate materials, contact films for plate making, masking films, proof papers, recording films, and photoresists. [Prior Art] Conventionally, as a means of increasing the sensitivity of photopolymerizable compositions to light, there has been a method of adding 4,4'-bis(dimethylamino)benzophenone (common name: Michler's ketone) to benzophenone (for example, Kiyomi Kato, Shoji Nakahara, "Introduction to UV Curing Technology," p. 65, Kobunshi Publishing Co., Ltd. (1984)) and a method of adding an organic peroxide to this method (Japanese Patent Application Laid-open No. 60-35725), which certainly have an effect on the polymerization rate. However, the sensitivity obtained with the former is not sufficient for use in photoresists and other applications, and with the latter, when the amount of organic peroxide required to obtain high sensitivity is used, the photosensitive resin liquid and coating The stability over time (hereinafter simply referred to as stability), including thermal stability, of the resulting film is not sufficient. Furthermore, JP-A-60-76503 describes a photoinitiator composition that uses a special organic peroxide and an organic dye compound, but this also has high sensitivity but is not as stable as above. Not enough. [Problems to be solved by the invention] Sensitivity is the most important characteristic of photopolymerizable compositions, and even when work efficiency is taken into account, the appearance of products with higher sensitivity is currently awaited. . In addition, if the stability of the photopolymerizable composition is insufficient, when the drying temperature after applying the photosensitive liquid is high,
Exposure time is not constant, which causes variations in quality and makes it impossible to obtain clear images with good reproducibility.
A so-called "fogging" phenomenon occurs. An object of the present invention is to obtain a photopolymerizable composition which is highly sensitive and has improved stability of a photosensitive solution and a coated film. [Means for Solving the Problems] The present inventors have achieved photopolymerization with high sensitivity and excellent stability by using a combination of a specific organic peroxide and a photosensitizer as a photopolymerization initiator. The inventors have discovered that a sexual composition can be obtained, leading to the present invention. That is, the present invention relates to a compound having an ethylenically unsaturated double bond, a benzophenone group-containing polyhydric peroxyester represented by the following general formula (), and a 4,4'-bis(dialkylamino) represented by the general formula (). The present invention provides a highly sensitive photopolymerizable composition containing a photopolymerization initiator consisting of benzophenone. General formula () [In the formula, R ₁ and R′ ₁ each have a carbon number of 4 to 8
tertiary alkyl group, or a tertiary alkyl group having 9 to 12 carbon atoms
The aralkyl groups R ₂ and R' ₂ each represent a hydrogen atom, a tertiary alkoxy group having 4 to 8 carbon atoms, or a tertiary aralkyloxy group having 9 to 12 carbon atoms. ] General formula () [However, R represents an alkyl group, a cycloalkyl group, or a hydroxyalkyl group having 1 to 6 carbon atoms. ] The compound having an ethylenically unsaturated double bond used in the present invention may be any compound that can be polymerized with a photopolymerization initiator, such as acrylic acid, methacrylic acid, itaconic acid, maleic acid and its anhydride, phthalate, etc. Acids and their anhydrides, unsaturated acids such as fumaric acid, methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, glycidyl (meth)acrylate, hydroxyethyl (meth)acrylate, Unsaturated acid esters such as dimethyl maleate, diethyl maleate, dimethyl fumarate, pentaerythritol tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, etc. and styrene, acrylamide, acrylonitrile, N-vinylpyrrolidone, vinyl acetate, and various unsaturated polyesters, unsaturated polyethers, unsaturated polyurethanes, and (meth)acrylate compounds having epoxy groups. In addition, the general formula () used as a photopolymerization initiator in the present invention [In the formula, R ₁ and R′ ₁ each have a carbon number of 4 to 8
tertiary alkyl group, or a tertiary alkyl group having 9 to 12 carbon atoms
The aralkyl groups R ₂ and R' ₂ each represent a hydrogen atom, a tertiary alkoxy group having 4 to 8 carbon atoms, or a tertiary aralkyloxy group having 9 to 12 carbon atoms. ] Examples of benzophenone group-containing polyhydric peroxyesters include 3,3',4,4'-tetra-(tert-butylperoxycarbonyl)benzophenone, 3,3',4,4'-tetra-( tertiary amylperoxycarbonyl)benzophenone, 3,
3',4,4'-tetra(tertiary hexylperoxycarbonyl)benzophenone, 3,3',4,4'-tetra(tertiary octylperoxycarbonyl)benzophenone, 3,3',4,4'-tetra( cumylperoxycarbonyl)benzophenone, 3,3′,
4,4'-tetra(p-isopropylcumylperoxycarbonyl)benzophenone, and the like. General formula () used in the present invention [However, R represents an alkyl group, a cycloalkyl group, or a hydroxyalkyl group having 1 to 6 carbon atoms. ] Examples of the compounds represented by include 4,4'-bis(dimethylamino)benzophenone, 4,4'-bis(diethylamino)benzophenone, 4,4'-bis(dicyclohexylamino)benzophenone,
Examples include 4,4'-bis(dihydroxyethylamino)benzophenone. Among these, 4,4'-bis(dimethylamino)benzophenone and 4,4'-
Particularly preferred is bis(diethylamino)benzophenone. The blending ratio of each of the above components is 0.01 to 0.01 to 100 parts by weight of the compound having an ethylenically unsaturated double bond, and the benzophenone group-containing polyhydric peroxyester represented by the general formula () and the compound represented by the general formula (), respectively. 100 parts by weight, preferably 0.1 to 30 parts by weight, particularly preferably 1 to 30 parts by weight. The compounding ratio of compound (a) represented by general formula () and compound (b) represented by general formula () is a:b in weight ratio.
is preferably 1:10 to 10:1. A photopolymerizable composition with excellent performance cannot be obtained outside the range of the above-mentioned blending amount and blending ratio. The photopolymerizable composition of the present invention has as an essential component a compound having an ethylenically unsaturated double bond that is polymerizable with the photopolymerization initiator, but may optionally include a binder resin, a polymerization inhibitor, a dye, etc. can be used by appropriately blending them. Binder resin is used as a coating film forming aid for printing plate materials and photoresists for the purpose of improving physical properties, and is usually used in an amount of 50 to 500 parts by weight per 100 parts by weight of a compound having an ethylenically unsaturated double bond. It is preferable to use it in moderation. Examples of the binder resin include (meth)acrylate resin, vinylpyrrolidone resin, and vinyl alcohol resin, and the resin may or may not contain a polymeric group. Examples of polymerization inhibitors include p-methoxyphenol and hydroquinone, and examples of dyes include brilliant green, ethyl violet, eosin, and erythrosin B. The photopolymerizable composition of the present invention is used as a photosensitive resin sheet by coating on various substrates,
At this time, the photopolymerizable composition is methyl ethyl ketone,
Dilute it approximately 5 to 100 times with a solvent such as isopropanol or methyl cellosolve, and apply it on the substrate using a method such as spin coating, roll coating, or bar coating.
It is used by applying it evenly to a thickness of 0.5 to 50 μm. The thus obtained photosensitive resin sheet undergoes a photopolymerization reaction by being irradiated with actinic light such as ultraviolet rays, and a predetermined image is obtained by developing the sheet. [Effects of the Invention] The photopolymerizable composition of the present invention uses a combination of the compound represented by the general formula () and the compound represented by the general formula () as a photopolymerization initiator. It has significantly higher sensitivity than other compositions, and also has superior stability. Therefore,
It can be used in many photopolymerization reactions, and can be applied to a wide variety of fields such as various image forming materials, photocurable resins, paints, and printing inks. [Examples] The present invention will be explained in more detail below using Examples and Comparative Examples. Parts in the examples indicate parts by weight. Examples 1 to 2 and Comparative Examples 1 to 3 A photosensitive liquid was prepared by uniformly mixing photopolymerizable compositions having the following composition. These photosensitive solutions were applied onto a grained anodized aluminum plate using a whirler so that the dry film thickness was 2 μm, and dried at 40° C. for 5 minutes to obtain a photosensitive substrate. - 100 parts of epoxy acrylate (EA-800 manufactured by Shin-Nakamura Chemical Co., Ltd.) - 100 parts of poly(butyl acrylate/ethyl acrylate/methacrylic acid) (mole ratio 50/40/10, molecular weight 100,000) - 3,3',4,4'-tetra-(tert-butylperoxycarbonyl)benzophenone (hereinafter
Parts shown in Table 1: 4,4'-bis(diethylamino)benzophenone (hereinafter referred to as EMK) Parts: Benzophenone (hereinafter referred to as BP) Parts: Di-tert-butylperoxyisophthalate (hereinafter referred to as PBIF) 1,800 parts of methyl cellosolve A step tablet (No. 2 manufactured by Kodaku Corporation) was placed on top of this photosensitive substrate and adhered in vacuum, and exposed for 1.5 seconds with a 2K.W. ultra-high pressure mercury lamp from a distance of 60cm.
Commercially available alkaline developer (manufactured by Fuji Photo Film Co., Ltd.)
Development was carried out with DN-3C (water-diluted product), and after drying, the number of steps in the exposed area by the step tablet obtained was determined by visual judgment, and this was taken as the initial sensitivity. The results are shown in Table 1. The higher the number of steps, the higher the sensitivity.If there is a difference of 2 steps, the sensitivity will be 2.
Double. Next, place the photosensitive substrate before exposure in a heat insulator at 55℃.
After standing still for 48 hours, post-exposure development was performed in the same manner as above to examine stability. The results are shown in Table 1. In addition,
Here, "normal" indicates that normal development is possible after exposure, and "impossible" indicates that "fogging" occurs and normal development is impossible.

[Table] *Image cannot be taken. **Not exposed to light at all.
As is clear from the results in Table 1, BTTB and
All of the products of the present invention that are used in combination with EMK have higher sensitivity and better stability than those of comparative examples. It is clear from Comparative Examples 1 and 2 that the present invention is based on the synergistic effect of BTTB and EMK, but in addition, in Example 1, 5 parts of EMK have a benzophenone group and a peroxy group in the same molecule. The excellent synergistic effect is also recognized by the fact that by using a small amount of 8 parts of BTTB, a significantly superior performance is obtained than when 34 parts of BP and PBIF were used separately in Comparative Example 3. Example 3 and Comparative Examples 4 to 5 A photosensitive solution having the following composition was prepared according to Example 1, and coated on coated paper (Pearl Coat #100, manufactured by Mitsubishi Paper Mills Co., Ltd.) using a bar coater. A photosensitive sheet was obtained by uniformly applying the film to a dry film thickness of 1 μm and drying. Using this photosensitive sheet, the initial sensitivity and stability were examined in the same manner as in Example 1 except that water was used for development. The results are shown in Table 2.・Pentaerythritol triacrylate
100 parts/Poly-N-vinylpyrrolidone (molecular weight 360,000)
100 parts ・ BTTB Shown in Table 2 ・ 4,4'-bis(dimethylamino)benzophenone (hereinafter referred to as MK) 〃 〃 ・ BP 〃 〃 ・ PBIF 〃 〃 ・ Methyl cellosolve 5000〃

[Table] From the results in Table 2, it is clear that the samples of the present invention have higher sensitivity and better stability than those of the comparative examples. Example 4 and Comparative Examples 6 to 7 A photosensitive solution having the following composition was prepared according to Example 1, and it was coated on a copper plate (JISH3100 (C1100P) manufactured by Japan Test Panel Industry Co., Ltd.) polished to a near mirror surface. To,
The coating was applied uniformly using a rotary coating machine so that the dry coating thickness was 5 μm, and the coating was dried to obtain a photosensitive copper plate. Using this photosensitive copper plate, the initial sensitivity and stability were examined in the same manner as in Example 1, except that isopropanol/water (weight ratio 50/50) was used for development. The results are shown in Table 3.・Trimethylolpropane triacrylate
50 parts Poly(methyl methacrylate/methacrylic acid) (mole ratio 50/50, molecular weight 80,000) 150 parts 3,3',4,4'-tetra(tertiary hexylperoxycarbonyl)benzophenone (hereinafter
BTTH) The parts shown in Table 3 EMK 〃 〃 ・ BP 〃 〃 ・ PBIF 〃 〃 ・ 2,4,6-tri(4-methoxyphenyl)
Thiapyrylium fluoroborate (MTF)
) Ethyl violet 2〃 ・ P-methoxyphenol 0.1〃 ・ Methyl ethyl ketone 500〃 ・ Isopropanol 500〃

[Table] From the results in Table 3, it is clear that the product of the present invention has higher sensitivity and better stability than Comparative Example 6 and Comparative Example 7 in which a special organic dye was used instead of EMK.

Claims (1)

[Scope of Claims] 1. A compound having an ethylenically unsaturated double bond, a benzophenone group-containing polyhydric peroxyester represented by the following general formula (), and a 4,4'-bis(dialkylamino) represented by the general formula (). ) A highly sensitive photopolymerizable composition containing a photopolymerization initiator consisting of benzophenone. general formula [In the formula, R ₁ and R′ ₁ each have a carbon number of 4 to 8
tertiary alkyl group, or a tertiary alkyl group having 9 to 12 carbon atoms
The aralkyl groups R ₂ and R' ₂ each represent a hydrogen atom, a tertiary alkoxy group having 4 to 8 carbon atoms, or a tertiary aralkyloxy group having 9 to 12 carbon atoms. ] General formula [However, R represents an alkyl group, a cycloalkyl group, or a hydroxyalkyl group having 1 to 6 carbon atoms. ]