JPS6317903A - Photo-setting resin composition - Google Patents

Abstract

PURPOSE:To obtain a resin composition curable by irradiation of light of visible range as well as ultraviolet range and useful as a plate-making material, image- forming material, etc., by dispersing minute resin particles in a specific photo-sensitive liquid resin. CONSTITUTION:The objective composition can be produced by dispersing minute resin particles having particle diameter of 0.01-6mu [e.g. internally crosslinked (co)polymer of a monomer having polymerizable ethylenic unsaturated group] in a photosensitive liquid resin such as a photo-polymerizable resin containing a compound giving a polymerization initiator by the irradiation of light of visible range (400-800nm) (e.g. arylthiomethyl benzophenone) or a compound system (e.g. porphine and diaryl iodonium salt, etc.) or a photo-crosslinkable resin having a functional group sensitive to light of visible range. The amount of the resin particles is preferably 0.1-40pts.(wt.) per 100pts. of the above liquid resin.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a photocurable resin composition that can be cured by light irradiation not only with ultraviolet rays but also with visible light.

Such compositions are attracting attention as photoresists, inks, paints, festivals, and printing plate-making materials, as well as image-forming materials that use laser light and photosensitive materials that can replace silver salts.

One of the characteristics of such photocurable resin compositions is that they contain a compound or a compound system that becomes a polymerization initiator when irradiated with light in the visible light region.
No. 78442. On the other hand, photocrosslinkable resin compositions incorporating functional groups having photosensitivity in the visible light region have also been proposed.

In general, photocurable resin compositions do not contain volatile solvents so that they do not require drying or setting of the solvent by raising the temperature, so they must have a viscosity that allows sufficient workability without a solvent. Must. Therefore, for example, in the case of paint, although there is no problem with a low film thickness, in a thick film coating system, sagging occurs and it is not possible to apply a thick enough film in one application. To enable thick coating, it is possible to incorporate silica, extender pigments, etc. that improve sagging performance, but inorganic fine particles have drawbacks such as deterioration of weather resistance and appearance of the film, and deterioration of physical performance. There is. In addition, inorganic fine particles absorb and scatter light due to differences in refractive index, particle distribution, and elemental composition compared to resins, resulting in insufficient curing due to light not reaching the necessary areas, and conversely, inorganic particles absorbing and scattering light due to differences in refractive index, particle distribution, and elemental composition. There are disadvantages such as hardening.

Furthermore, since the cured film is difficult to be sufficiently crosslinked three-dimensionally, there are disadvantages such as poor physical properties such as tensile strength, hardness, adhesion, abrasion resistance, and printing resistance.

An object of the present invention is to control the viscosity and improve the physical properties of a photocurable resin composition without the above-mentioned drawbacks.

This invention involves dispersing minute resin particles with a particle size of 0.01 to 6 μm in a photosensitive liquid resin containing a compound or compound system that becomes a polymerization initiator when irradiated with light in the visible light region. The present invention provides a photocurable resin composition comprising:

Preferably, the fine resin particles are made of a polymer or copolymer of a monomer having an internally crosslinked polymerizable ethylenically unsaturated group, and contain 0 parts by weight per 100 parts by weight of the photosensitive liquid resin.
．． Preferably, it is used in a proportion of 1 to 40 parts by weight.

According to the present invention, by incorporating minute resin particles into a photocurable resin composition, the viscosity of the composition can be controlled to have a yield value. In other words, the apparent viscosity of the composition when it is at rest is high, which increases the film thickness limit at which no sagging occurs, but when shear stress is applied, the apparent viscosity decreases, so workability is not impaired ( Thick film coating is possible.

Since the fine resin particles are similar in chemical and optical composition to the matrix resin, they impart optical transparency to the composition and do not reduce the efficiency of sensitivity to light irradiation. Therefore, it is less likely that some parts will be insufficiently cured, or that unnecessary parts will be hardened. Furthermore, the appearance of the composition after curing is not impaired.

The photocurable resin composition of the present invention has improved physical properties such as tensile strength, hardness, adhesion, bending strength, and abrasion resistance, even when compared to a composition that does not contain minute resin particles. This is because the physical interaction between the fine resin particles and the matrix resin causes a relaxation phenomenon when external stress is applied to the film.

As described above, according to the present invention, the irradiated light is not scattered or absorbed, is optically transparent, does not become cloudy, or blurred, and furthermore, the physical properties can be improved by physical interaction with the matrix resin. Moreover, it is possible to control the rheology of the photocurable resin composition.

Various methods have been proposed to produce fine resin particles, one of which involves mixing an ethylenically unsaturated monomer with a crosslinkable comonomer in an aqueous medium. A fine resin particle dispersion is created by suspension polymerization or emulsion polymerization, and water is removed by solvent substitution, azeotropy, centrifugation, drying, etc. to obtain fine resin particles.Other methods include aliphatic hydrocarbons, etc. Ethylenically unsaturated monomers and crosslinkable copolymers in low SP organic solvents or non-aqueous organic solvents that dissolve monomers but do not dissolve polymers, such as high SP organic solvents such as esters, ketones, and alcohols. This is a method called the NAD method or precipitation method, in which the resulting fine resin particle copolymer is copolymerized with the NAD method or precipitation method.

The fine resin particles of the present invention may be produced by any of the above methods. The method for producing minute resin particles using a water-soluble resin having an amphoteric group described in JP-A-58-129066 by the present inventors may also be used. The particle size needs to be 0.01 to 6 μm from the viewpoint of miscibility, reactivity, and storage stability.

Examples of ethylenically unsaturated monomers include methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate. Alkyl esters of acrylic acid or methacrylic acid and other monomers having ethylenically unsaturated bonds that can be copolymerized with them, such as styrene, α-methylstyrene, vinyltoluene, t-butylstyrene, ethylene, propylene, acetic acid Vinyl, vinyl propionate, acrylonitrile, methacrylate trile, dimethylaminoethyl (meth)acrylate, etc. Two or more types of these monomers may be used.

Crosslinkable comonomers are monomers and/or monomers having two or more radically polymerizable ethylenically unsaturated bonds in the molecule.
Alternatively, it contains two types of ethylenically unsaturated group-containing monomers each carrying groups that can react with each other.

Examples of monomers having two or more radically polymerizable ethylenically unsaturated groups in the molecule include polymerizable unsaturated monocarphonic acid esters of polyhydric alcohols, polymerizable unsaturated alcohol esters of polybasic acids, and two or more radically polymerizable ethylenically unsaturated groups. There are aromatic compounds substituted with the above vinyl groups, examples of which include the following compounds.

Ethylene glycol diacrylate, ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, 1,4-butanediol dimethacrylate Acrylate, neopentyl glycol diacrylate, 1,6-hexanediol diacrylate, pentaerythritol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, pentaerythritol dimethacrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, glycerol dimethacrylate , glycerol diacrylate, glycerol allyloxy dimethacrylate, 1,1.1-1-lishydroxymethylethane diacrylate, LLI-) lishydroxymethylethane triacrylate, LLI-
Trishydroxymethylethane dimethacrylate, 1.
1.1-) Lishydroxymethylethane trimethacrylate, LLI-) Lishydroxymethylpropane diacrylate, 1. Ll-) lishydroxymethylpropane triacrylate, 1. Ll-) Lishydroxymethylpropane dimethacrylate, 1, Ll-trishydroxymethylpropane tritacrylate, triallyl cyanurate, triallyl isocyanurate, triallyl trimellitate, diallyl terephthalate, diallyl phthalate and divinylbenzene.

In addition, examples of monomers having two types of ethylenically unsaturated groups each carrying mutually reactive groups include epoxy group-containing ethylenically unsaturated monomers such as glycidyl acrylate and glycidyl methacrylate, and acrylic acid and methacrylic acid. Carboxyl group-containing ethylenically unsaturated monomers such as acid and crotonic acid are the most representative, but mutually reactive groups are not limited to these.
For example, various compounds have been proposed, such as amine and carbonyl, epoxide and carboxylic acid anhydride, amine and carboxylic acid chloride, alkyleneimine and carbonyl, organoalkoxysilane and carboxyl, hydroxyl and isocyanate, etc., and the present invention broadly encompasses these. It is something to do.

Micro resin particles produced in an aqueous medium or a non-aqueous organic medium can be isolated by a method such as filtration, spray drying, or freeze drying, and then cut into appropriate particle sizes by using a mill or the like. It can be used after being pulverized, or a synthesized dispersion can be used by replacing the medium with the solvent.

Generally speaking, it is desirable to control the particle size of the particles obtained by the polymerization method. 0.01~0.6μ
For particles of 0.2 to 2, the emulsion polymerization method and NAD method
The precipitation method is most suitable for particles with a size of 1 to 6 μ, and the suspension polymerization method is most suitable for particles with a size of 1 to 6 μ. In addition, rheology control is possible by adjusting the particle size distribution by the polymerization process or by mixing the particles after polymerization, if necessary. The fine resin particles have their own glass transition point and solubility parameter in relation to the matrix resin.
The refractive index can be controlled by the components. In addition, in the structure, by arranging functional groups or unsaturated groups that can react with each other or with the matrix resin on the surface of the resin particles, the interaction between the resin particles and between the resin particles and the matrix resin can be further enhanced. Furthermore, a sensitizer that is effective during photocuring, a promoter substance that promotes the reaction, and a functional substance that allows the composition to exhibit high functionality after curing may be loaded and included on the surface or inside of the resin particles. Of course it is possible.

The fine resin particles preferably account for 0.1 to 40 parts by weight per 100 parts by weight of the photosensitive liquid resin in order to control the rheology of the composition and improve the physical performance after curing.

The photosensitive liquid resin used in the present invention can be selected from these known liquid resins depending on the purpose.

For example, the resin composition of the present invention used as a resist or plate-making material is selected to be one that can be dissolved in water, alkali, organic solvents, etc. so that the parts not irradiated with light can be removed from the base sheet. be done.

Photocurable resins generally have the following basic composition: +1) Photocrosslinkable (or non-crosslinkable) polymer or oligomer (2) Photopolymerizable monomer or low molecular weight oligomer (3)
Contains a photopolymerization initiator (or sensitizer) (4) thermal polymerization inhibitor (or stabilizer), and optionally contains additives such as a sensitizer and a coloring agent.

Examples of the polymer or oligomer (1) include unsaturated polyester resin, urethane acrylate resin, epoxy acrylate resin, polyester acrylate resin,
Spiran acrylate resin, polyether acrylate resin, etc. are well known.

The photopolymerizable monomer or low molecular weight oligomer in (2) includes the low molecular weight oligomer of the polymer in +1) above, as well as styrene, vinyltoluene, divinylbenzene, vinyl acetate, (meth)acrylonitrile, and (meth)acrylic acid ester. [Methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, (meth)
2-ethylhexyl acrylate, glycidyl (meth)acrylate, ethylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, etc.], diethyl itaconate, dibutyl itaconate, diethyl fumarate, diethyl maleate, etc. It is being

Among photocurable resin compositions that can be cured by light irradiation even in the visible light region, photopolymerizable resin compositions must contain a compound or compound system that becomes a polymerization initiator by light irradiation in the visible light region as (3). .

Many of these compounds include a sensitizer alone or a combination of a sensitizer and a radical generator. Examples of these include eosin/amines, riboflavin, cyanine pigments, and carponic acid imide (JP-A-47-32).
819), a compound having a trihalomethyl group conjugated to a triazine ring due to ethylenic unsaturation (JP-A-48-
36281), triphenylimidazolyl dimer (Japanese Patent Publication No. 48-38403), Ori-ruthiomethylbenzophenone (Japanese Patent Application Publication No. 48-67377), cobalt complex (Japanese Patent Publication No. 10724-1987, No. 59-10731), p. - Unsaturated ketone conjugated with dialkylaminoallylidene (JP-A-54-155292), polycyclic quinone and tertiary amine (
JP-A-52-134692), porphine or metal porphine and diaryliodonium salt (JP-A-6O-7)
8442).

Sensitizers such as merocyanine dyes, aromatic conjugated ketones, acyl-substituted clarin and acridine derivatives, and 0-acyl oximes such as 3-phenyl-5-isoxazoline, 2.4.6-tris(trichloromethyl)-L3 ,5
-) Combination with radical generators such as halides such as riazine and thiols such as 2-mercaptobenzimidazole (Journal of the Chemical Society of Japan 1984. (lLp, 192)
etc.

In addition, photo-crosslinkable types such as those with styrylquinolinium introduced into the side chain of PVA and those with p-phenylene bis (α-cyanobutadienecarboxylic acid) as a photosensitive group are good even under high illuminance and short exposure. It can be cited as indicating a high degree of sensitivity.

These may be added directly to the photosensitive liquid resin, or may be partially or completely supported on fine resin particles. The amount added is 0.01 to 40 parts by weight per 100 parts by weight of the photosensitive liquid resin.

The photocurable resin composition of the present invention may optionally contain other initiators (having absorption on the relatively long wavelength side), non-reactive resins, thermal polymerization inhibitors, plasticizers, inorganic particles, It can contain thinner and the like.

As light sources suitable for the photocurable resin composition of the present invention, laser beams such as high-pressure mercury lamps, ultra-high-pressure mercury lamps, high-pressure xenon lamps, halogen lamps, fluorescent lamps, He-Ne, He-Cd + Ar, etc. can be used. .

In particular, Ar laser has 488.0 and 514.5 parts m, H
The e-Ne laser has a strong emission energy of 633 parts m, and the He-Cd laser has a strong emission energy of 441.6 parts m, and can be used advantageously.

The present invention performs rheology control of photocurable resin before curing by using micro resin particles instead of inorganic additives, thereby forming a bond between the matrix resin and the optical,
Various drawbacks caused by the presence of inorganic additives having chemically different properties can be eliminated.

Furthermore, in the cured film, the physical performance of the film can be increased (improved) due to the effect of the interaction between the polymer and the fine resin particles.

Therefore, it can be advantageously used when it is desired to improve both the hardness and flexibility of the film, when curing is insufficient due to high-speed exposure, or when special printing resistance is required as a plate material. .

Applications of these technologies include letterpress, flat plate, intaglio, and screen printing plate materials or hardening printing inks in the printing industry, paints, packaging materials, and adhesives in the color material industry, and shadow masks, shadow masks, and other applications in the electronics industry. As a resist, dry film, or sealant for electronic components such as printed wiring, IC, and LSI, and plates and parts in the metal surface treatment industry, ceramics industry, glass industry, precision machinery industry, building materials industry, automobile industry, and shipbuilding industry. It can be applied as a material obtained by a curing method using light energy, such as as a photoresist in the textile industry, as a surface treatment agent in the textile industry, and as an enzyme fixative or cavity filling agent in the biomedical industry.

The present invention will be explained in detail below with reference to examples, but these examples do not in any way imply that the present invention can be used. "Parts" and "%" in the examples are based on weight.

Reference Example 1 Ion system equipped with a stirrer, nitrogen inlet tube, temperature control device, condenser, and decanter. 134 parts of bishydroxyethyl taurine, 130 parts of neopentyl glycol, 236 parts of azelaic acid, 186 parts of phthalic anhydride, and 27 parts of xylene are charged into a Kolben, and the temperature is raised. The water produced by the reaction is removed by azeotroping with the xycin.

The temperature was raised to 190°C over about 2 hours from the start of refluxing, stirring and dehydration were continued until the acid value equivalent to carboxylic acid reached 145, and then the mixture was cooled to 140°C.

Next, the temperature was maintained at 140°C, and "Cardura E10"
314 parts of persatic acid glycidyl ester (manufactured by Shell) were added dropwise over 30 minutes, and stirring was continued for 2 hours to complete the reaction. The resulting polyester resin has an acid value of 59. The hydroxyl value was 90 and the Mn was 1054.

Reference Example 2 II equipped with a stirrer, a cooler, and a temperature control device. In a reaction vessel, 380 parts of deionized water, 50 parts of the emulsifier having amphoteric group obtained in Reference Example 1, and 5 parts of dimethylethanolamine were charged, and dissolved while stirring at a temperature of 80°C. 2.5 parts deionized water 5 parts
0 parts and a solution dissolved in 1.6 parts of dimethylethanolamine, and 75 parts of methyl methacrylate, 75 parts of ethylene glycol dimethacrylate, 40 parts of styrene, and n
- A mixed solution consisting of 35 parts of butyl acrylate was added dropwise over a period of 90 minutes, and stirring was continued for an additional 90 minutes to obtain an aqueous dispersion of fine resin particles with a non-volatile content of 38% and an average particle diameter of 55 mμ. .

By freeze-drying this dispersion, fine resin particles could be obtained in powder form.

Example 1 In a container, 30 parts of N,N-dimethylacrylamide, 20 parts of N-vinylpyrrolidone, 100 parts of polyether urethane acrylate resin obtained by modifying polyethylene glycol with a molecular weight of 500, 3 parts of 2,4-diethylthioxanthone, and Fine resin particle powder 1 obtained in Reference Example 2
A photocurable resin composition was obtained by taking 0 parts and sufficiently stirring and mixing.

When this composition was applied to a glass plate and its sag limit was examined, it was found to be 350μ. Next, 100 on the same glass plate.
It was coated so as to have a particle diameter of μ and cured by irradiating it with an ultra-high pressure mercury lamp for 5 minutes under a filter that cant out short wavelengths of 400 nm or less. The obtained film had a hardness of 2H. In addition, the wear wheel C3-1 was measured using a taper wear tester.
The amount of wear reduction in the wear test using No. 7 was 15 cm/100 times.

Comparative Example 1 A photocurable resin composition was obtained in exactly the same manner as in Example 1 except that the fine resin particles were not used. The sagging limit of this composition was 200μ.

The hardness of the cured film was 2H, and the amount of abrasion reduction was 25 cm/100 times.

Example 2 In a container, 1:100 parts of pentaerythritol methacrylate, 50 parts of epoxy diacrylate obtained by modifying a bis-epi type epoxy resin, 2,4.6-tris(trichloromethyl)-L3,5-) liazine 2 parts of merocyanine dye, 100 parts of methyl ethyl ketone, and 15 parts of the fine resin particle powder obtained in Reference Example 2 were taken, stirred thoroughly, and then coated on an aluminum plate to a thickness of 2 μm. After sufficient drying, a cured phase resin film could be obtained by irradiating with light using an ultra-high pressure mercury lamp. Next, the composition previously coated with 2 μm was irradiated with an argon laser having a wavelength of 488 μm as a light source with a beam diameter of 100 μm, and its curability was evaluated by line sensitometric measurement. The obtained line adhered to the material without dissolving even during washout.

Claims (3)

[Claims] (1) Photopolymerizable resins containing a compound or compound system that becomes a polymerization initiator when irradiated with light in the visible light region of 400 to 800 nm, or photocrosslinkable resins that have a functional group that is photosensitive in the visible light region. A photocurable resin composition comprising fine resin particles having a particle size of 0.01 to 6μ dispersed in a photosensitive liquid resin. (2) The photocurable resin composition according to item 1, wherein the minute resin particles are a polymer or copolymer of a monomer having an internally crosslinked polymerizable ethylenically unsaturated group. (3) The photocurable resin composition according to item 1 or 2, in which the fine resin particles are added in an amount of 0.1 to 40 parts by weight per 100 parts by weight of the photosensitive liquid resin.