JPS63305346A - Photosensitive resin composition - Google Patents

Abstract

PURPOSE:To easily obtain a cured material which has the excellent sensitivity and no amine odor and the sufficient mechanical strength by exposing for a short period, by incorporating an amide compd. having a specified structure with a prescribed ratio together with a photopolymerization initiator in the titled material. CONSTITUTION:The titled composition contains the amide compd. shown by formula I and the photopolymerization initiator, and said amide compd. is necessary to be incorporated in the titled composition in an amount of >=5wt.% of the compd. based on the total weight of the titled composition. In the case that the additional mount of the compd. is about 3wt.%, the sensitivity of the titled composition somewhat increases, but, the sufficient effect is not obtd., in the reduction of an exposure time and the formation on a relief such as a minimum point, etc. The compounding amount of the photopolymerization initiator is usually 0.001-10wt.% based on the total weight of the titled composition. Thus, the cured material which has no amine order the excellent sensitivity measured based on insolubility of the cured material, and the excellent sensitivity measured based on the mechanical strength and the hardness is obtd.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a novel photosensitive resin composition.

More specifically, 1 the present invention is suitable as an image resist for plate making such as planography, letterpress, and gravure, and as a resist for etching processing of printed wiring and integrated circuits, or as a component of photosensitive paints, adhesives, inks, etc. This invention relates to a highly sensitive photosensitive resin composition.

Background of the Invention In recent years, photosensitive resins have undergone rapid development and are used in many fields, such as image resists for plate making such as lithography, letterpress, and gravure, and resists for etching processes such as printed wiring, integrated circuits, and shadow masks. It is widely used as a photoresist and as a photosensitive vehicle for paints, adhesives, printing inks, etc.

The photosensitive resin is usually photopolymerized by irradiation with active light such as ultraviolet rays to form a cured product having a three-dimensional structure and insoluble in water and organic solvents. In such photosensitive resins,
In order to improve productivity and quality, shortening exposure time has become one of the important issues.

By the way, increasing the output of the light source and increasing the sensitivity of the photosensitive resin are effective ways to shorten the exposure time.
For the former, it is unavoidable that costs increase in terms of equipment size and energy consumption, so until now efforts have been made to improve the sensitivity of the photosensitive resin itself, for example, by increasing the photopolymerization initiator or Much effort has been made to improve photosensitizers.

As for the photosensitizer, 1, for example, instead of the conventional benzoin alkyl ether, 2,2-dimethoxy-2-
It has been discovered that phenylacetophenone has the effect of further increasing the sensitivity of M group K materials, and has recently been widely used in photosensitive resin compositions for UV inks, paints, letterpress production, and the like.

However, only with such photoinitiators.

The method for achieving high sensitivity is to use a cured film with a thickness of 0, such as a resist for etching processes such as printed wiring and integrated circuits.
．． Although it is effective when it is as thin as 2fl or less, it is not necessarily effective when it is as thick as 0.4 to 7n, such as for letterpress printing. This is because, although increasing the concentration of the photopolymerization initiator shortens the induction period for surface hardening, the curing speed in the thickness direction actually decreases due to self-absorption of actinic rays by the photopolymerization initiator. This is to do so.

On the other hand, regarding photosensitizers, amine compounds and phosphorus compounds have been widely studied [Japanese Patent Publications No. 52-3431, No. 54-10986, "Painting Techniques" Vol. 20, 1
37 pages (1981)], many have already been put into practical use.

However, this photosensitizer does not increase sensitivity.

Although it does not have the drawbacks tNL mentioned above, it does have the following two serious drawbacks. That is, the first drawback is that when using amine photosensitizers, due to the amine odor, local exhaust equipment is required when handling in small spaces or in large quantities.
In addition, especially when lower alkylamines are used, safety and health considerations must be taken, such as measures against irritation of the skin and mucous membranes. The second drawback is that amine-based
Even with any type of photosensitizer such as a phosphorus-based sensitizer, if these are added to increase the sensitivity, the sensitivity will improve considerably based on insolubilization, but image-forming exposure and post-exposure must be processed separately. In fields that involve processes, such as letterpress printing, there are many cases where post-exposure is performed after image-forming exposure, an uncured resin recovery process (only for liquid photosensitive resins), and a development process. In such cases, during image-forming exposure, physical properties such as mechanical strength of the cured product are not fully expressed, so highlight halftone dots and reliefs of isolated fine lines and dots are susceptible to damage before post-exposure. That's true.

This is when the photosensitizer is used to increase sensitivity.

The concentration of radicals generated in the system increases due to the sensitizing effect of light irradiation, and as a result, the number of polymer molecules generated increases, and the average degree of polymerization per polymer molecule decreases, resulting in failure of three-dimensional crosslinking. It is thought that this is because the mechanical strength of the photocured product at the image forming exposure step decreases. In addition, when sensitizing using a phosphorus compound,
If a proton donor such as a carboxyl group coexists in the system, a problem arises in that it coordinates with the phosphorus compound and inhibits the sensitizing effect.

Furthermore, a photosensitive resin composition with enhanced sensitivity and thermal stability has been proposed using a prepolymer having a specific segment and a specific amine sensitizer (JP-A-59-1999).
232338), this product lacks versatility because the prepolymer segments are limited.

In order to improve these drawbacks of conventional photosensitizers, attempts have been made to use compounds that have a polymerizable double bond and an amino group in the same molecule as a radically polymerizable monomer and photosensitizer. (Japanese Patent Publications No. 58-50611, 58-50612, 58-50613, JP-A-53-98384, 55-362)
No. 40, No. 62-511), such
Compounds having a radically polymerizable double bond and an amine group in the molecule can improve the mechanical strength of the photocured product after image-forming exposure, which is a drawback when using the above-mentioned amine-based sensitizers. However, the problem of amine odor remains unresolved.

This amine odor can be suppressed to some extent by making the alkyl group or hydroxyalkyl group bonded to the nitrogen atom have a large number of carbon atoms. When introducing,
It is not practical because the amine sensitizing activity is significantly reduced.

Problems to be Solved by the Invention The present invention overcomes the drawbacks of such conventional photosensitive resin compositions and provides sufficient mechanical performance even when irradiated with actinic light at a small exposure dose in image forming exposure. Provided is a photosensitive resin composition that has excellent sensitivity, such as giving a photocured product with optical strength, does not cause a decrease in sensitivity even when the cured film is thick, and has a substantially amine odor. It was carefully designed for the purpose of

Means for Solving the Problems The present inventors have developed a highly sensitive photosensitive resin composition that does not have an amine odor and can easily provide a cured product with sufficient mechanical strength by short exposure to light. As a result of intensive research for development, it was discovered that a composition containing an amide compound having a polymerizable double bond with a specific structure in a predetermined ratio together with a photopolymerization initiator was suitable for the purpose. Based on this knowledge, the present invention was completed.

That is, the present invention is based on the general formula (A) (wherein R1 is a hydrogen atom or a methyl group, R2 and R3 are each an alkyl group or a hydroxyalkyl group having 1 to 4 carbon atoms, and Y is a hydroxyalkyl group having 1 to 10 carbon atoms). The present invention provides a photosensitive resin composition containing an amide compound represented by (which is a linear or branched alkylene group) and (B) a photopolymerization initiator.

The present invention will be explained in detail below.

In the composition of the present invention, the amide compound used as component (A) is an acrylic amide derivative or a methacrylic amide derivative represented by the general formula (in which R1R2R5 and Y have the same meanings as above).

The number of carbon atoms in the alkyl group or hydroxyalkyl group of R2 and R3 in the general formula (I) must be in the range of 1 to 4, preferably 1 or 2. When the number of carbon atoms is 5 or more, sufficient improvement in sensitivity cannot be obtained.

In addition, Y in the formula is a linear or branched alkylene group having 1 to 10 carbon atoms, and when the number of carbon atoms is 11 or more, the cured product has sufficient mechanical strength, for example, during short-time image forming exposure. is not obtained. The number of carbon atoms in Y is generally preferably in the range of 1 to 6 from the viewpoint of availability.

As for the amide compound represented by the general formula (1),
For example, N-(N';N'-dimethylaminomethyl)-acrylamide,N-(N',N'-dimethylaminoethyl)-acrylamide,N-(N',N'-dimethylaminepropyl)-acrylamide, N −[3−(N
',N'-dimethylamino)-2-methylpropylaminocouacrylamide, N-(N',N'-diethylamineethyl)-acrylamide, N-(N'-methyl-N'-ethylaminoethyl)-acrylamide, N
-(N', N'-dimethylaminooctyl)-acrylamide, N -(N', N'-diethylaminodecyl)
-acrylamide, N-(N7N'-di-hydroxyethylaminoprobyl)-acrylamide and the corresponding methacrylamide. These may be used alone or in combination of two or more.

In the composition of the present invention, it is necessary to contain the amide compound represented by the general formula (1) in an amount of 5% by weight or more based on the total weight of the composition. Even if this amount is about 3 weight factors, the sensitivity will be improved slightly, but sufficient effects will not be obtained in terms of shortening the exposure time and forming reliefs such as minimum points.

Therefore, in order to obtain a practical effect, it is necessary to use the content in an amount of 5% by weight or more.

In the composition of the present invention, the photopolymerization initiator used as component (B) can be completely irradiated with actinic rays to form an amide compound represented by the general formula (I) and other ethylenic compounds used as desired. There is no particular restriction as long as the ethylenic addition polymerizable group such as an unsaturated monomer or prepolymer can initiate radical addition polymerization.

Examples of such photopolymerization initiators include benzoin, benzoin ethyl ether, benzoin-n-furobyl ether, penzoin-isoglobyl ether, benzoin alkyl ethers such as benzoin isobutyl-ethernato, and 2,2-dimethoxy-2. -Phenylacetophenone, benzophenone, benzyl, diacetyl, diphenyl sulfide, eosin, thionin, 9.10-
Examples include anthraquinone, 2-ethyl-9,10-anthraquinone, and the like.

These photo-1 initiators may be used alone or in combination of two or more, and the amount added is usually 0.001 to 1 liter based on the total weight of the composition.
Selected within the range of 0% by weight.

In addition to the above-mentioned essential components, the composition of the present invention may include a prepolymer, a binder polymer, an ethylenically unsaturated monomer other than the amide compound represented by the above general formula, a thermal polymerization inhibitor, Trace amounts of UV absorbers, dyes, pigments,
A lubricant, a surfactant, etc. can be added.

As the prepolymer, for example, unsaturated polyester,
Unsaturated polyurethane, oligoester acrylate, oligoester methacrylate, unsaturated polyamide, unsaturated polyimide, unsaturated polyether, unsaturated polyacrylate, unsaturated polymethacrylate and various modified products thereof, carbon-carbon double bond' Examples include various rubber compounds that exhibit t'ff. These prepolymers (1) usually have an average molecular weight of substantially 500 or more.

Specific examples of such prepolymers include unsaturated polyesters and alkyds such as maleic acid,
Unsaturated dibasic acids such as fumaric acid and itaconic acid or their acid anhydrides and ethylene glycol, fluoropylene gellicol, diethylene glycol, triethylene glycol, glycerin, trimethylolpropane, pentaerythritol, 1, 4 having a terminal hydroxyl group - polyesters with polyhydric alcohols such as polybutadiene, hydrogenated or non-hydrogenated 1,2-polybutadiene-acrylonitrile copolymers; Examples include polyesters substituted with saturated polybasic acids such as phthalic anhydride and trimellitic acid, or polyesters modified with drying oil fatty acids or semi-drying oil fatty acids. Examples of unsaturated polyurethanes include those with two or more terminal hydroxyl groups. Urethane derived from polyol and polyincyanate A product in which an addition polymerizable unsaturated group is introduced using the terminal incyanate group or hydroxyl group of a compound linked by a urethane base valve 1 For example, the above-mentioned polyhydric alcohol,
1,4-polybutadiene, hydrogenated or non-hydrogenated 1,2-polybutadiene, butadiene-styrene copolymer, butadiene-acrylonitrile copolymer, etc. and toluylene diinocyanate having a polyol terminal hydroxyl group such as polyester polyol and polyether polyol. , diphenylmethane-4,4'-diisocyanate, hexamethylene diisocyanate, and other polyisocyanates into which unsaturated groups are introduced by utilizing the reactivity of the terminal incyanate or hydroxyl groups of polyurethane.

Alternatively, an unsaturated group may be introduced by reacting an incyanate with a compound having an active hydrogen such as a hydroxyl group, a carboxyl group, or an amine group among the unsaturated carboxylic acids or esters thereof, or a reaction between an unsaturated carboxylic acid having a carboxyl group and a hydroxyl group. Examples include compounds into which unsaturated groups have been introduced by reaction, and compounds obtained by linking the above-mentioned unsaturated polyesters with polyisocyanates. In addition, oligoester acrylates can be produced by co-condensing acrylic acid or methacrylic acid in an ester reaction system of polybasic acid and polyhydric alcohol to adjust their respective molar ratios and have a molecular weight of 200 to 500.
Compounds such as adipic acid, phthalic acid, inphthalic acid or acid anhydrides and ethylene glycol, globylene glycol, diethylene glycol, triethylene glycol, glycerin, trimethylolpropane,
Those condensed by coexisting acrylic acid or methacrylic acid in an ester reaction system with a polyhydric alcohol such as pentaerythritol, epoxy acrylates, for example, t is a polyhydric alcohol, polyhydric phenol, or polyphenol and epichlorohydrin or alkylene oxide. Ester of acrylic acid or methacrylic acid with a compound having an epoxy group obtained by polycondensation reaction with polycondensation reaction, addition-polymerizable carbon-
A compound obtained by reacting a polymer compound with a carbon double bond, such as polyvinyl alcohol, a polymer compound with a hydroxyl group such as cellulose, with an unsaturated carboxylic acid or its acid anhydride, or acrylic acid or methacrylic acid. Polymer compounds with carboxyl groups such as acid polymers or copolymers with unsaturated alcohols, glycidyl acrylates, methacrylates, etc. ester-bonded;
Reaction of a copolymer containing glycidyl acrylate or methacrylate with acrylic acid or methacrylic acid, such as a reaction product of a copolymer containing maleic anhydride with allyl alcohol, hydroxyalkyl acrylate or methacrylate, etc. Can list things. In addition, various rubber compounds include (1) 1.4
-Polybutadiene, 1,2-polybutadiene, butadiene-styrene copolymer, butadiene-acrylonitrile copolymer, KPDM.

(It) Hydrogenated product of (1) above, imputely isoprene copolymer, ethylene propylene copolymer, or (
Examples include unsaturated modified rubbers in which ethylenically unsaturated groups are introduced into the various rubber compounds shown in 1) using known techniques. Although the compound (1) above can be used as it is, it is convenient to use various rubber compounds having a terminal functional group as K for introducing the unsaturated group. Further, in the case of a rubber compound having a l,2-polybutadiene segment, the unsaturated group can be easily introduced by adding maleic anhydride to the compound.

As the binder polymer, among the above prepolymers, those having no ethylenically unsaturated groups can be used, and water-soluble or alcohol-soluble polyamides, cellulose, acylated cellulose, etherified cellulose,
Petroleum resins and the like can also be used.

The prepolymer and binder polymer may be used in combination, and the amount of these polymers used varies depending on the use and purpose, but is usually 20 to 90% based on the total weight of the composition.
Selected based on weight.

Furthermore, the molecular weight of these polymers is selected depending on whether the photosensitive resin composition is to be made into a solid molded product at room temperature or kept in a liquid state.

The ethylenically unsaturated monomers include known compounds, such as unsaturated carboxylic acids such as acrylic acid and methacrylic acid, or esters thereof, such as alkyl-, cycloalkyl-, halogenated alkyl-, alkoxyalkyl-,
Hydroxyalkyl, aminoalkyl, tetrahydrofurfuryl, allyl, chrycidyl, benzyl
, phenoxy-acrylates and methacrylates, mono- or diacrylates and methacrylates of alkylene glycols, polyoxyalkylene glycols, trimethylolpropane triacrylates and methacrylates,
Acrylamide, methacrylamide or derivatives thereof, such as pentaerythritol tetraacrylate and methacrylate, e.g.
-substituted or N,N'-substituted acrylamides and methacrylamides, diacetone acrylamides and methacrylamides, N,N'-alkylenebisacrylamides and methacrylamides, allyl compounds such as allyl alcohol, allyl isocyanate, diallyl phthalate, triallyl cyanurate, maleic acid, maleic anhydride, fumaric acid or esters thereof, such as mono- or dimaleates and fumarates of alkyl, alkyl halides, alkoxyalkyl, other unsaturated compounds such as styrene, vinyltoluene, divinylbenzene, Examples include N-vinylcarbazole and N-vinylpyrrolidone. Some of these monomers can be converted into azide compounds 5 such as 4,4'-diazidostilbene, p-phenylene-bisacide, 4,4'-diazidobenzophenone, 4,4'-diazidophenylmethane, 4
, 4'-Diazidochalcone, 2.6-di(4'-diazidobenzal)-cyclohexanone, 4.4'-diazidostilbene-α-carboxylic acid, 4°4'-diazidodiphenyl, 4,4'- A substitute such as sodium diazidostilbene-2,2'-disulfonate may also be used.

There is no particular restriction on the amount of these ethylenically unsaturated monomers used, and it may be selected as appropriate depending on the use and purpose.
Generally, a range of 10 to 95 weight units is used based on the total weight of the composition. .

In addition, examples of thermal polymerization inhibitors include hydroquinone,
Mono-tert-butylhydroquinone, benzoquinone, Z, S
-diphenyl-p-benzoquinone, picric acid, di-p
-Fluorophenylamine.

p-methoxyphenol, 2,6-di-tert-butyl-p-
Examples include cresol. These thermal polymerization inhibitors are intended to prevent thermal polymerization reactions (dark reactions) and therefore the addition of the thermal polymerization inhibitor (t is based on the total weight of the composition).

It is preferable to select it within the range of 0.005 to 5% by weight.

In the composition of the present invention, when a compound that forms an amine salt or an adduct with the amide compound represented by the general formula (1) is used as an optionally added component,
It is necessary to select the amount used within a range smaller than the equivalent amount to the amide compound. Examples of such compounds include protonic acids such as carboxylic acids and sulfonic acids, and Lewis acids.

Effects of the Invention The photosensitive resin composition of the present invention contains an amide compound with a specific structure and a photopolymerization initiator as essential components, has no amine odor, and has a ratio determined based on insolubilization of the cured product. Both sensitivity and specific sensitivity determined based on mechanical strength and hardness are excellent.

In addition, by appropriately selecting components added as desired in addition to the essential components, compositions applicable to various fields can be obtained.For example, for letterpress production, UV ink, UV
Coating agents, mold making agents, photosensitive adhesives, resist materials, etc., printing, paints, electronic components and circuit boards, optics.

It is particularly suitable for use in fields such as biochemistry and medicine, where highly sensitive photosensitive resins are required.

EXAMPLES Next, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these examples in any way.

Examples 1 to 3, Comparative Examples 1 to 3 Photosensitive resin compositions having the compositions shown in Table 1 were prepared and cured to a cured thickness under a constant exposure amount and a film thickness of 50 μm as follows. The amount of exposure required for this was determined. As a result, t-
f: Shown in the gi table.

(1) Measurement of cured thickness under a constant exposure dragon The uncured portion was removed and the thickness was measured.

(2) Measurement of exposure amount required to cure a film thickness of 50 μm The composition was coated on a polyester support to a thickness of t-50 μm, and then exposed to light, and the exposure amount at which residual film was observed was measured.

The unsaturated polyurethane (*1) was prepared as follows.

Polyethylene adipate (diol, Mn-2000)
Toluidine diincyanate (TD
2.4 body / 2,6 body - 372) is 34.8
0.5 parts by weight of dibutyltin dilaurate and t-0.5 parts by weight were added, and the mixture was reacted at 50° C. for 4 hours to obtain polyethylene adipate having incyanate groups at both ends. to this,
Polypropylene glycol (diol, Mn-200
0) 100 parts by weight was added to obtain a polyester-polyether block (terminated incyanate) having an average molecular weight of 6,500. The terminal incyanate block body 30
0 parts by weight.

z5fold i part of 2-hydroxyethyl methacrylate, 0
．． It was added to 1 part by weight of hydroquinone and reacted at 70°C for 2 hours to obtain a prepolymer.

As can be seen from Table 1, the composition of the present invention has higher sensitivity than the comparative composition.

Example 4. Comparative Example 4.5 Photosensitive resin compositions shown in Table 2 were prepared, and the cured thickness under a constant exposure amount was determined in the same manner as above.

In addition, based on the insolubilization sensitivity, the tensile strength (K9/d) ft of the cured product cured for 1 m, measurement temperature 20 ° C, dumbbell shape J Engineering S-1, cross head speed 5 ota, /
It was determined under the condition of min. The results are shown in Table 2.

As you can see from Table 2, even if it is cured to the same thickness,
In the case of the comparative example, the tensile strength was very low and it was not sufficiently cured, but the composition of the present invention showed not only insolubilization sensitivity but also
The tensile strength is also sufficiently high. Further, although all of the comparative examples had a strong amine odor, substantially no amine odor was observed in the composition of the present invention.

Claims (1)

[Claims] 1 (A) General formula ▲ Numerical formula, chemical formula, table, etc. ▼ (R_1 in the formula is a hydrogen atom or a methyl group, R_2 and R
_3 is an alkyl group or hydroxyalkyl group each having 1 to 4 carbon atoms, and Y is a linear or branched alkylene group having 1 to 10 carbon atoms); and (B) a photopolymerization initiator. A photosensitive resin composition comprising: 2. The photosensitive resin composition according to claim 1, wherein the content of the amide compound is at least 5% by weight based on the total weight of the composition.