JPH0757783B2 - Method for producing photocurable resin - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a resin that is cured by light to form a transparent film.

(Prior Art) A resin that is cured by light to form a transparent film is known as a photocurable resin.

JP-A-58-199342 describes the use of a copolymer of a hydroxyl group-containing monomer and a nitrogen-containing monomer as a photocurable resin. The copolymer has a general formula as a hydroxyl group-containing monomer. A compound represented by the general formula Or The compound represented by is to be included. here,
R ₁ and R ₂ represent H, CH ₃ or C ₂ H ₅ , n represents an integer of 1-3, R ₃ represents H or CH ₃ , X represents O or NH, R ₄ represents An alkylene group having 2 or 3 carbon atoms is represented, R ₅ , R ₆ and R ₇ are H or an alkyl group having 1 to 4 carbon atoms, and Y is an acid group.

JP-A-58-199342 discloses that the above copolymer contains the hydroxyl group-containing monomer in a proportion of 20-70% by weight and the nitrogen-containing monomer in a proportion of 5-80% by weight. Must be provided. Further, the above-mentioned publication describes that, in order to use it as a photocurable resin for the above-mentioned copolymer, it is necessary to first make a copolymer and then use this by dissolving it in water or another solvent. There is. Moreover, the above publication merely teaches that an organic solvent such as cellosolve, amide or ether is used for the copolymerization to make the copolymer.

However, the teaching of this publication has drawbacks. Its biggest drawback is that an organic solvent has to be used for the copolymerization. Organic solvents such as cellosolve are harmful to the human body.Therefore, when copolymerization is performed, special consideration must be taken so as not to damage the health of workers.In addition, the solvent is collected in the manufacturing equipment and the waste liquid is treated. It required a special device. Because of this, implementations according to this teaching are costly. Further, this teaching was also complicated in that an organic solvent must be used during the copolymerization and redissolved in water or another solvent during coating.

The reason why organic solvents have been exclusively used for copolymerization so far is that the resulting copolymers are poorly soluble in water, so when the copolymerization is carried out in an aqueous solvent, turbidity or insoluble matter is generated. ,
This is because precipitation or phase separation occurs in an extreme case and a uniform copolymer cannot be obtained. This is because if the copolymer is not uniform, the photocurability will be uneven and the photocurable resin will not be of good quality.

(Problems to be Solved by the Invention) The present invention is to use a non-toxic aqueous solvent instead of an organic solvent as a main solvent when producing a resin, and to obtain an aqueous solution of the resulting copolymer. It was made in an attempt to make it usable as a photocurable resin as it is.

(Means for Solving the Problem) This inventor decides to copolymerize by selecting a specific one from the hydroxyl group-containing monomer and the nitrogen-containing monomer taught in JP-A-58-199342. Further, it was found that when an aqueous solvent added with acetic acid is used, the obtained copolymer can be copolymerized to the end while being dissolved, and thus a uniform copolymer can be obtained using the aqueous solvent. . Further, the present inventor has found that, as described above, the copolymerization ratio is not limited to the monomer mixing ratio as specified in JP-A-58-199342, and a wider copolymerization ratio can be obtained. . The present invention was made based on such knowledge.

(Summary of Invention) A hydroxyl-containing monomer represented by and a smaller amount of the general formula Or A nitrogen-containing monomer represented by is dissolved in an aqueous solvent, acetic acid is added, and copolymerized with a water-soluble polymerization initiator, which is a method for producing a photocurable resin. To do. Here, R ₁ , R ₂ and R ₃ are all H
Or represents CH _3, R ₄ represents CH ₃ or C ₂ H _5, X represents a halogen.

(Explanation for Each Requirement) The hydroxyl group-containing monomer represented by [Formula 1] is all water-soluble. Therefore, this monomer can be dissolved in water and polymerized during the polymerization. Specific examples of this monomer are 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate and 2-vidroxypropyl methacrylate.

The nitrogen-containing monomers represented by [Formula 2] and [Formula 3] are also
All are water soluble. Therefore, this monomer can also be dissolved in water and polymerized during the polymerization. Among these, specific examples of the monomer belonging to [Formula 2] are dimethylaminopropyl acrylamide, dimethylaminopropyl methacrylamide, and the like. Further, specific examples of the monomer belonging to [Formula 3] are acrylamidopropyltrimethylammonium chloride, methacrylamideamidopropyltrimethylammonium chloride, etc. corresponding to the chloride of the monomer of [Formula 2].

In the present invention, when the monomer of [Formula 1] and the monomer of [Formula 2] or [Formula 3] are copolymerized, the monomer of [Formula 1] is represented by [Formula 2] or More than the monomer of the formula [3] is used. This is because the obtained copolymer requires that the amount of the monomer of [Formula 1] is larger than that of the monomer of [Formula 2] or [Formula 3]. The two types of monomers are copolymerized at a coexisting ratio to form a copolymer. That is, the monomer of [Formula 1] is 60% by weight, and the monomer of [Formula 2] is
When they are mixed and copolymerized at a ratio of 40% by weight, a copolymer copolymerized at about this ratio is obtained.

When a copolymer containing a large amount of the monomer of the formula 1 is to be obtained, it is desirable that the monomer of the formula 1 is not added all at once but added later. . The same applies when the concentration of the polymerization initiator is low. The reason is,
This is because in such a case, the increase in viscosity becomes large during the polymerization process and the entire aqueous solution tends to gel, which is to prevent this.

In the present invention, in addition to the monomers of [Formula 1] to [Formula 3], other monomers may be added to form a ternary or higher copolymer. Other monomers include dimethylacrylamide, N
-Vinylpyrrolidone, diacetone acrylamide, N-
Methylolacrylamide, methoxymethylacrylamide, ethoxymethylacrylamide, acrylic acid, methacrylic acid, acrylamide, methacrylamide, methoxymethylacrylamide, ethoxymethylacrylamide, acryloylmorpholine, glycerin monoacrylate, diethylene glycol mono (meth) acrylate, triethylene glycol mono (meth ) Acrylate and the like can be used. Since these monomers are also water-soluble, they can be polymerized as water-soluble. The amount of these other monomers should be 20% by weight or less in the copolymer.

In this invention, the above-mentioned monomer mixture is dissolved in an aqueous solvent and copolymerized. The aqueous solvent is a solvent whose main component is water. Thus, the aqueous solvent may consist of water only, such as deionized water, or it may have a small amount of water-soluble liquid added to it.

This invention is most characterized by adding acetic acid to an aqueous solvent. Although the total amount of acetic acid may be added to the aqueous solvent from the beginning of the polymerization, acetic acid may be added as the copolymerization proceeds. Regarding the amount of acetic acid to be added, firstly, when the amount of the monomer of the formula [3] is large, the amount of acetic acid is increased, and secondly, the copolymer of the formula [1] having a large amount of monomer is obtained. Also in this case, the amount of acetic acid is increased, and thirdly, also in the case of obtaining a copolymer having a high degree of polymerization, the amount of acetic acid is increased.
The amount of acetic acid is suitably 5 to 25% by weight in the aqueous solvent.

Various kinds of water-soluble polymerization initiators can be used. For example, 2,2'-azobis (N, N '
-Dimethylene isobutylamidine) dihydrochloride, 2,2
-'Azobis (2-amidinopropane) dihydrochloride,
4,4-'azobis (4-cyanopentanoic acid), 2,
2'-azobis (2-methyl-N- [1,1-bis (hydroxymethyl) 2-hydroxyethyl] propionamide, 2,2'-azobis [2-methyl-N- (2-hydroxyethyl)] propion Amide, 2,2'-azobis (isobutylamide) dihydrate, ammonium persulfate, etc. can be used, and the amount of the polymerization initiator is preferably 0.1 to 2% by weight based on the monomer.

In the present invention, the order of addition of the monomer, acetic acid and the polymerization initiator is arbitrary. By heating the aqueous solvent to which these are added, copolymerization is promoted to obtain a copolymer. Suitable heating temperature is 50-90 ℃, especially 60-80 ℃
Is preferred. A heating time of several hours is suitable.

The copolymer is obtained in a state of being dissolved in an aqueous solvent. The product obtained according to the invention is therefore a viscous liquid. The liquid is usually transparent although it may be slightly colored. The coloring is, for example, light yellow red. The product leaves only a small amount of residual monomer. The amount of residual monomer is usually less than 1% by weight.

This product can be used as it is as a photocurable resin. When it is used as a photocurable resin, it is disclosed in
The diazo or azide compound is added to this product, as taught in 58-199342. A desired solution may be applied to the surface of the article, dried, covered with a masking material, and exposed to light. Then, the residual monomer and acetic acid are evaporated from the solution, the copolymer remains behind, the part exposed to the light hardens, and the part not exposed to the light remains as it is. It can be treated with a suitable solvent to leave only the cured part.
Therefore, this product can be directly used as a photocurable resin.

The product obtained according to the present invention contains a copolymer consisting of a hydroxyl group-containing monomer and a nitrogen-containing monomer, so that when a film is formed from this, the film is tough and dye-based. This makes it easy to color. In particular, it is easy to dye with an acid dye. Therefore, by coloring this film, a photographic filter, a printing filter,
It can be used as an image pickup device of a video camera, a color filter of a liquid crystal display device, and the like.

(Effect of the Invention) According to the present invention, a hydroxyl group-containing monomer represented by [Formula 1] and a smaller amount of a nitrogen-containing monomer represented by [Formula 2] or [Formula 3] are used as an aqueous solution. Since it was dissolved in a solvent, acetic acid was added to an aqueous solvent, and copolymerization was performed with a water-soluble polymerization initiator, the resulting copolymer can be allowed to proceed without making it difficult to dissolve. Thus, it is possible to prepare a copolymer solution having a uniform composition. There, since no organic solvent is used, there is no risk of degrading the health of workers, no special consideration is required for solvent recovery or solvent disposal, and therefore it is possible to produce a copolymer in a safe and advantageous manner. it can. Moreover, since the obtained product is uniform and exhibits good photocurability, it has a wide range of uses as a photocurable resin. Further, the resin produced here contains many hydroxyl group-containing monomers of [Formula 1], and [Formula 2] or [Formula 3]
Since it contains a small amount of the above-mentioned nitrogen-containing monomer, it is tough as a film and has good dyeability with dyes, and is therefore suitable for making a colored film. Furthermore, since the product obtained according to the present invention contains only a small amount of residual monomer, acetic acid and water in addition to the copolymer, the product can be directly used on the surface of a desired article. Since it can be applied to form a film, it is convenient for use. The present invention provides such benefits.

(Examples) The advantages of the present invention will be specifically described with reference to the following examples and comparative examples. In the following, simply "parts" means "parts by weight".

Example 1 2-Hydroxyethylmethacrylate 75 parts Dimethylaminopropylmethacrylamide 15 Methacrylamide 10 2,2'-Azobis- (2-amidinopropane) .2 hydrochloric acid group 0.8 Acetic acid 50 Deionized water 250 4 of the above mixtures The mixture was placed in a neck flask, immersed in a water bath at 75 ° C., purged with nitrogen, and the mixture was added dropwise using a metering pump in 4 hours. Furthermore, it stirred for 4 hours after that. The liquid temperature was maintained at 72-73 ° C from the start of the addition to the end of the reaction.

The reaction product was a pale yellow-red transparent liquid. When this was measured by liquid chromatography, the residual monomer concentration was 0.8% by weight of the charged amount. 20% solids of this reaction product
The viscosity at 20 ° C. was measured with a Brutsk Field viscometer to find that it was 280 cp and was easy to apply.

A diazo resin was added to this reaction product as a sensitizer and used as a photocurable resist material as described below.

10 parts of the above reaction product was diluted with 15 parts of deionized water and passed through a membrane filter having a pore size of 0.45 μm, followed by a membrane filter having a pore size of 0.20 μm. Diazo resin 0.
After adding 2 parts and dissolving uniformly with a shaker, the pore size of 0.2
It was passed through a μm filter to obtain a photosensitive solution. The photosensitive solution was poured into a glass disk, spin-coated at 1500 rpm and then prebaked at 70 ° C. for 3 minutes to obtain a photosensitive solution.

A photo mask is overlaid on this photosensitive solution, and 80mJ with an ultra-high pressure mercury lamp.
/ cm ² exposure. This was developed with water at 25 ° C. for 1 minute, dried and then heat-treated at 130 ° C. for 20 minutes.

Place this sample plate in a dyeing bath of the following composition containing a blue dye.
After shaking for 3 minutes at 70 ° C., washing with warm water and drying, a clear blue image was obtained.

Composition of dyeing bath Blue 5P (manufactured by Nippon Kayaku Co., Ltd.) 5 parts Deionized water (adjusted to pH 4 with acetic acid) 995 parts Comparative Example 1 In Example 1, acetic acid was not used, and deionized water was 300 parts. Except for carrying out, the reaction was carried out in the same manner as in Example 1. The reaction liquid began to become cloudy 3 hours after the start of the addition of the monomer liquid, and after 6 hours the viscosity became so high that stirring was difficult and the liquid became opaque.

Example 2 2-Hydroxyethyl methacrylate 65 parts 2-Hydroxypropyl methacrylate 10 Dimethylaminopropyl methacrylamide 15 Dimethylacrylamide 102,2'-azobis- (2-amidinopropane) dihydrochloride 0.8 Acetic acid 50 Deionized water 250 Above The mixture was added dropwise in the same manner as in Example 1 over 4 hours, and the mixture was stirred for 4 hours to complete the reaction. The reaction solution was slightly turbid, but no precipitate was observed even after standing for 1 week.

Comparative Example 2 The procedure of Example 2 was repeated, except that acetic acid was replaced with water, and white turbidity started 2 hours after the start of dropping the monomer and after 5 hours. A suspension containing many lumps was formed. When this was left overnight, it separated into a sediment and a supernatant.

Example 3 83 parts 2-Hydroxyethyl methacrylate Methacrylamidopropyltrimethylammonium chloride 10 Dimethylacrylamide 72,2'-Azobis- (2-amidinopropane) dihydrochloride 0.8 Acetic acid 50 Deionized water 250 The above mixture was added to Example 1 Was treated and reacted in exactly the same manner as in.

The reaction product is a slightly yellow transparent liquid with a solid content of 20
The% viscosity at 20 ° C. was 315 cp.

Claims (1)

[Claims] 1. A general formula A hydroxyl-containing monomer represented by and a smaller amount of the general formula Or A method for producing a photocurable resin, which comprises dissolving a nitrogen-containing monomer represented by the following in an aqueous solvent, adding acetic acid, and copolymerizing with a water-soluble polymerization initiator. However, R ₁ ,
R ₂ and R ₃ each represent H or CH ₃ , and R ₄ is CH ₃ or
C ₂ H ₅ and X is halogen.