JP2010015169A - Photosensitive resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a highly sensitive photosensitive resin composition having a hardness as required. <P>SOLUTION: This photosensitive resin composition for letterpress printing contains a soluble synthetic polymer compound, a photopolymerizable unsaturated compound, and a photopolymerization initiator. The photopolymerizable unsaturated compound is a ring-opening reaction product of a polyglycidyl ether of a polyhydric alcohol, a methacrylic acid and an acrylic acid, and a reaction ratio of the methacrylic acid is within a range of 25-75 mol%. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a photosensitive resin composition that is highly sensitive and has a required hardness. The photosensitive resin composition layer is provided on a metal or plastic substrate to form a photosensitive resin relief plate. Is available

  Conventionally, actinic rays are irradiated through a negative or positive original film having a transparent portion on the photosensitive resin layer, photopolymerization is caused to the photosensitive resin corresponding to the transparent portion of the original film, and then the unphotopolymerized portion is appropriately used. It is known that a relief is formed by removing with a simple solvent and that this is used as a printing plate material.

  In general, the printing quality of the photosensitive resin relief printing plate is greatly influenced by the hardness of the photosensitive resin layer. When the photosensitive resin layer is hard, the deformation of the top of the relief due to the printing pressure is small, so fine lines and dots The image reproducibility is excellent, but the ink transferability tends to deteriorate as the resin hardness increases. Therefore, the resin hardness has an optimum hardness range, and Shore D is between 50 ° and 65 °. Is desired

On the other hand, in order to obtain sufficient resin hardness, it is known that a compound having a methacrylic acid epoxy ester group is effective as a photopolymerizable unsaturated compound. There was a problem of becoming a resin composition.
Therefore, in order to solve the above problems, it is conceivable to increase the amount of the photopolymerization initiator for the purpose of increasing the sensitivity. However, the photocuring at the bottom near the base (support) is absorbed by the absorption of the photopolymerization initiator. This is a problem that the image reproducibility is deteriorated due to insufficient image quality.

  This invention solves the problem of the conventional photosensitive resin letterpress, and makes it a subject to provide the photosensitive resin composition of high hardness and high sensitivity.

  In order to solve the above-mentioned problems, the present inventors have previously proposed a compound having a methacrylic acid epoxy ester as a photopolymerizable unsaturated compound as a conventional example, which is effective for increasing the hardness. Focusing on the problem of the problem, we conducted extensive research to solve the shortcomings. As a result, in order to solve the drawbacks of low sensitivity due to the methacrylic acid epoxy ester group, the acrylic acid epoxy ester group and the methacrylic acid epoxy ester group, which are excellent in photopolymerizability, are contained in a specific range so that the hardness is high. A highly sensitive photosensitive resin composition was achieved, and the present invention was finally completed. That is, the present invention provides a photosensitive resin composition containing at least a soluble synthetic polymer compound, a photopolymerizable unsaturated compound and a photopolymerization initiator, wherein the photopolymerizable unsaturated compound is a polyglycidyl ether of a polyhydric alcohol. It is a ring-opening addition reaction product of methacrylic acid and acrylic acid, and the reaction ratio of methacrylic acid is in the range of 25 to 75 mol%.

  As described above, the present invention having such a configuration greatly contributes to the industry because it has excellent sensitivity and can obtain the hardness required.

  In the present invention, a known synthetic polymer compound can be used as the synthetic polymer compound. For example, polyether amide (for example, JP-A No. 55-79437), polyether ester amide (for example, JP-A No. 58-113537), tertiary nitrogen-containing polyamide (for example, JP-A No. 50-76055), An ammonium salt type tertiary nitrogen atom-containing polyamide (for example, JP-A-53-36555), an addition polymer of an amide compound having at least one amide bond and an organic diisocyanate compound (for example, JP-A-58-140737), Examples include addition polymers of a diamine having no amide bond and an organic diisocyanate compound (for example, JP-A-4-97154), among which tertiary nitrogen atom-containing polyamides and ammonium salt type tertiary nitrogen atom-containing polyamides are preferred.

Next, the photopolymerizable unsaturated compound in the present invention is a ring-opening addition reaction product of polyglycidyl ether of polyhydric alcohol, methacrylic acid and acrylic acid. Examples include pentaerythritol, pentaerythritol, trimethylolpropane, glycerin, ethylene glycol, diethylene glycol, triethylene glycol, and ethylene oxide adducts of phthalic acid, among which trimethylolpropane is preferable.

The reaction ratio of methacrylic acid of the photopolymerizable unsaturated compound in the present invention is preferably in the range of 25 to 75 mol%, preferably 30 to 70 mol%, particularly 35 to 65 mol%. If it is less than 25 mol%, the hardness will be low, while if it exceeds 75 mol%, the sensitivity will be low, such being undesirable.
As a method for obtaining a photopolymerizable unsaturated compound having a reaction ratio of methacrylic acid in the range of 25 to 75 mol%, an addition reaction product of polyglycidyl ether of polyhydric alcohol and methacrylic acid is used as a polyhydric alcohol. Although it may be mixed at a ratio of 25 to 75 mol% with respect to the reaction product of glycidyl ether and acrylic acid, methacrylic acid and acrylic acid are added during the addition reaction with polyglycidyl ether of polyhydric alcohol from the viewpoint of production. It is desirable to mix within an appropriate range. In addition, although the reaction ratio of methacrylic acid and acrylic acid is 25-75 mol%, what is necessary is just to select suitably by the hardness of the photosensitive resin composition requested | required.

In addition, in the photosensitive resin composition of this invention, in order to improve stability at the time of manufacture or storage, it is possible to mix | blend a well-known thermal polymerization inhibitor. Specific examples of the thermal polymerization inhibitor include phenols, hydroquinones, catechols, phenothiazines and the like.
In addition, plasticizers, dyes, pigments, ultraviolet absorbers, fragrances, and the like can be added.

As a method for producing the photosensitive resin composition of the present invention, mixing of a soluble polymer compound, a photopolymerizable unsaturated compound, a photopolymerization initiator, and the like can be performed according to any known method. For example, a method of mixing in a molten state or a method of removing the solvent after mixing with an appropriate solvent such as alcohol may be used.
In addition, the composition of the present invention can be laminated into a sheet-like material such as a plate, film, or foil having a desired thickness by any method such as hot pressing, casting, melt extrusion, solution casting, or the like. it can.
As the support, any material such as steel, aluminum, glass, a plastic film such as a polyester film, and an aluminum-deposited film can be used.

EXAMPLES Next, although this invention is demonstrated concretely using an Example, this invention is not restrict | limited at all by these Examples. The term “parts” means parts by weight. Hardness and sensitivity were measured by the following methods.
1) Hardness: Measured at room temperature (25 ° C.) using a Shore durometer (Shore D type) manufactured by West German Zbic.
2) Sensitivity: A 21-step gray scale made by Stoffer was placed on the photosensitive resin surface, exposed for 2 minutes with a chemical lamp exposure machine made by JEOL Ltd., developed with neutral water at 25 ° C., and 10 at 70 ° C. It was represented by the number of cured steps of the relief obtained by performing 4 minutes post-exposure after drying for 4 minutes.

Example 1
ε-caprolactam 500 parts by weight, N, N′-bisaminopropylpiperazine and nylon salt of adipic acid 450 parts by weight, 1,3-bis (aminomethyl) cyclohexane and adipic acid 50 parts of nylon are polymerized. A polyamide having a tertiary nitrogen atom having a specific viscosity of 2.40 was obtained. 55 parts of the polyamide thus obtained was dissolved in 200 parts of methanol, and 36 parts of a reaction product of 3 parts of methacrylic acid, trimethylolpropane triglycidyl ether, 50 mol% of acrylic acid and 50 mol% of methacrylic acid were added to this solution. Then, 5 parts of N-ethyl-P-toluenesulfonamide, 0.1 part of hydroquinone monomethyl ether and 1 part of benzyldimethyl ketal were added to obtain a photosensitive resin composition solution.
This solution was cast onto a petri dish coated with Teflon (registered trademark), and after removing methanol in a dark room, it was further dried under reduced pressure at 40 ° C. overnight to obtain a composition sheet having a thickness of about 800 μm. This sheet is laminated on a 250 μm PET film coated with 20 μm brown pigment adhesive, and further covered with a 125 μm thick PET film coated with 2 μm polyvinyl alcohol on the upper surface of the composition, and hot-pressed at 110 ° C. for photosensitivity. A photosensitive resin original plate having a resin layer thickness of 700 μm was prepared. Next, the cover film was peeled off from the original plate, and an inspection negative was brought into close contact with the photosensitive resin surface and exposed for 2 minutes. After removing the negative, the film was developed with neutral water at 25 ° C. for 3 minutes and dried at 70 ° C. for 10 minutes. The sensitivity of the obtained photosensitive resin was 15 steps, and the resin hardness was 60 on Shore D, which was satisfactory.

Comparative Example 1
Photosensitivity was the same as in Example 1 except that the reaction product of triglycidyl roll of trimethylolpropane and 80 mol% of acrylic acid and 20 mol% of methacrylic acid was used as the photocurable unsaturated compound in Example 1. A resin composition was prepared. Although the sensitivity of the obtained photosensitive resin was 16 steps, the resin hardness was 48 on Shore D, which was not satisfactory.

Comparative Example 2
A photosensitive resin was prepared in the same manner as in Example 1 except that a reaction product of triglycidyl roll of trimethylolpropane, 20 mol% of acrylic acid and 80 mol% of methacrylic acid was used as the photocurable unsaturated compound. A composition was prepared. The resin hardness of the obtained photosensitive resin was satisfactory at 64 on Shore D, but the sensitivity was as low as 13 and was not satisfactory.

Example 2
A photosensitive resin was prepared in the same manner as in Example 1 except that a reaction product of triglycidyl ether of trimethylolpropane and 25 mol% of acrylic acid and 75 mol% of methacrylic acid was used as the photocurable unsaturated compound. A composition was made and a relief was made. The sensitivity of the obtained photosensitive resin was 15 and the resin hardness was 62 for Shore D, which was satisfactory.

Example 3
A photosensitive resin was prepared in the same manner as in Example 1 except that a reaction product of triglycidyl ether of trimethylolpropane and 70 mol% of acrylic acid and 30 mol% of methacrylic acid was used as the photocurable unsaturated compound of Example 1. A composition was made and a relief was made. The sensitivity of the obtained photosensitive resin was 16 and the resin hardness was 56 for Shore D, which was satisfactory.

Example 4
A photosensitive resin composition was obtained in the same manner as in Example 1 except that a reaction product of ethylene glycol diepoxy ether, 30 mol% acrylic acid and 70 mol% methacrylic acid was used as the photocurable unsaturated compound in Example 1. I made a thing and made a relief. The sensitivity of the obtained photosensitive resin was 15 steps, and the resin hardness was 57 at Shore D, which was satisfactory.

Example 5
Acrylonitrile was added to both ends of polyoxyethylene glycol having a number average molecular weight of 600, and this was hydrogen-reduced to obtain 55 parts by weight of an equimolar salt of α, ω-diaminopolyoxyethylene and adipic acid, ε-caprolactam 25 Parts by weight, and 20 parts by weight of an equimolar salt of hexamethylenediamine and adipic acid were subjected to melt polymerization under normal conditions to obtain a relative viscosity (polymer-1 g was dissolved in 100 ml of hydrated chloride and measured at 25 ° C.). A polyamide of 2.1 was obtained.
55 parts of the obtained polymer was dissolved in 200 parts of methanol, and in this solution, 39 parts of a reaction product of trimethylolpropane triglycidyl ether, acrylic acid 50 mol% and methacrylic acid 50 mol% used in Example 1, N -5 parts of ethyl-P-toluenesulfonamide, 0.1 part of hydroquinone monomethyl ether, and 1 part of benzyl dimethyl ketal were added to obtain a photosensitive resin composition solution. A photosensitive resin composition was prepared from the obtained photosensitive resin composition in the same manner as in Example 1, and a relief was prepared.
The sensitivity of the obtained photosensitive resin was 15 steps, and the resin hardness was 57 on Shore D, which was satisfactory.

Example 6
4-methylpentamethylenediamine 4 parts and N, N'-bis (3-aminopropyl) piperazine 14 parts are dissolved in methanol and reacted with 600 parts of polyethylene glycol (average molecular weight 600) and 370 parts of hexamethylene diisocyanate. 82 parts of urethane oligomer having isocyanate groups at both ends were gradually added to the diamine solution with stirring. Both reactions were completed in 10 minutes. A polymer obtained by taking this solution in a petri dish coated with Teflon (registered trademark), evaporating and removing methanol, and drying under reduced pressure contains 50% of a polyethylene glycol chain in the main chain and has a specific viscosity of 1.55. there were.
55 parts of the obtained polymer was dissolved in 200 parts of methanol, and 3.1 parts of adipic acid was added and dissolved. In this solution, 34 parts of a reaction product of triglycidyl ether of trimethylolpropane used in Example 2 with 25 mol% of acrylic acid and 75 mol% of methacrylic acid, 5 parts of N-ethyl-P-toluenesulfonamide, hydroquinone monomethyl ether 0.1 part and 1 part of benzyl dimethyl ketal were added, and the photosensitive resin composition was similarly created using Example 1, and the relief was created.
The sensitivity of the obtained photosensitive resin was 15 steps, and the resin hardness was 56 on Shore D, which was satisfactory.

Claims (1)

Synthetic polymer compounds such as polyether amides, polyether ester amides, tertiary nitrogen-containing polyamides, ammonium salt type tertiary nitrogen atom-containing polyamides, addition polymers of amide compounds having one or more amide bonds and organic diisocyanate compounds or amide bonds A photosensitive resin composition containing an addition polymer of a diamine and an organic diisocyanate compound, a photopolymerizable unsaturated compound, and a photopolymerization initiator, wherein the photopolymerizable unsaturated compound is a polyvalent trimethylolpropane. It is a ring-opening addition reaction product of polyglycidyl ether of polyhydric alcohol used as alcohol, methacrylic acid and acrylic acid, and the reaction ratio of methacrylic acid is in the range of 25 to 75 mol%. Photosensitive resin composition for letterpress printing.