JPS59166526A - Photo-setting composition - Google Patents

Abstract

PURPOSE:To prepare the titled composition having high rate of photosetting and excellent impact resistance and nail scratch resistance, by compounding a polyvalent epoxy resin with specific amount of a compound containing unsaturated double bond and hydroxyl group, and adding a specific component such as triaryl sulfonium complex, etc. CONSTITUTION:The objective composition is prepared by compounding (A) 40- 90wt%, preferably 50-80wt% of a polyvalent epoxy resin (e.g. bisphenol A diglycidyl ether) with (B) 60-10wt%, preferably 20-50wt% (A+B is 100wt%) of a compound containing unsaturated double bond and hydroxyl group (e.g. acrylic acid ester of trifunctional polypropylene glycol), (C) a triaryl sulfonium complex salt (preferably triaryl sulfonium hexafluoroantimonate, and its amount is 1- 3wt% of A+B) and (D) a polymerization initiator generating radicals with light or heat (e.g. benzoin).

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a photocurable composition with improved photocuring speed and excellent impact resistance and scratch resistance.

The curing reaction of resins using light is widely used from the viewpoint of safety and health due to labor saving, energy saving, and reduction of organic solvents.
It is starting to be put into practice.

One method of curing resin by irradiating it with light, especially ultraviolet rays, is to use a low-molecular-weight resin with unsaturated groups and a photosensitizer that generates photoradicals, and then irradiate it with light to cause radical polymerization. There is a method of curing the resin and a method of curing the resin by cationic ring-opening polymerization by blending an initiator that generates a Lewis acid when irradiated with light into an epoxy resin.

In addition to poor impact resistance and metal adhesion, the above-mentioned radical polymerization photocuring has the disadvantage of being susceptible to scratches due to the influence of oxygen in the air when forming a thin cured coating film. Polymerization photocuring has the disadvantage that the photocuring speed is slow and, especially when colored with pigments, the hardness in deep parts is insufficient.

The present invention overcomes these drawbacks of the prior art and provides a photocurable composition that has a fast photocuring rate and also has good impact resistance and scratch resistance.

That is, the present invention comprises (A) 40 to 90% by weight of a polyvalent epoxy resin, (B) 60 to 10% by weight of a compound containing both an unsaturated double bond and a hydroxyl group (However, (A) and (B) 100% by weight), (C)) a realylsulfonium complex salt, and (D) an initiator that generates radicals when exposed to light or heat.

Examples of the polyhydric epoxy resin (A) used in the present invention include diglycidyl ethers of polyhydric phenols such as bisphenol A1 tetrabromobisphenol A1 phenol novolak, cresol novolac, and bisphenol S, such as frindiol, Polyglycidyl ethers of polyhydric alcohols such as hexanediol, hydrogenated bisphenol A1 dimethylolbenzene, e.g. glycidyl esters of polybasic acids such as evaterephthalic acid, isophthalic acid, orthophthalic acid, adipic acid, e.g. paraoxybenzoic acid , glycidyl ether esters of oxycarboxylic acids such as metahydroxybenzoic acid, skeletal polyeboxides such as polybutadiene polyeboxide, epoxidized oils, or e.g. 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexane. 3,4-epoxy-2-methylcyclohexylmethyl-3,4-epoxy-2-methylcyclohegysancarboxylate and bis(3,4-epoxy-cyclohexyl)aziberto. An alicyclic polyepoxy resin containing a cyclohexene oxide group is used. The epoxy equivalent of the epoxy resin (A) above is preferably 500 or less, more preferably in the range of 100 to 250 from the viewpoint of photocurability, and two or more types of polyhydric epoxy resins may be used in combination. .

Examples of the above-mentioned (B) compounds containing an unsaturated double bond and a hydroxyl group used in the present invention include (I) hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, or hydroxyl group-containing monomers such as adducts of these hydroxyalkyl group-containing monomers and ε-caprolactone; , compounds containing hydroxyl groups, which are esters of polyhydric alcohols such as pentaerythritol, sorbitol, and cichentaerythritol and unsaturated carboxylic acids such as acrylic acid, methacrylic acid, fumaric acid, and itaconic acid. Hydroxyl group-terminated polyesters of polyhydric alcohols and polybasic acids, or esters of polyesters such as polycaprolactone and unsaturated carboxylic acids, containing hydroxyl groups, such as maleic anhydride, fumaric acid, etc. A hydroxyl-terminated unsaturated polyester resin using a basic acid as a part of a polybasic acid and condensed with a polyhydric alcohol, glycidyl acrylate, glycidyl methacrylate, β- Methyl glycidyl methacrylate or 9- is a resin containing a hydroxyl group and an unsaturated double bond obtained by reacting a glycidyl group-containing unsaturated monomer such as allyl glycidyl ether, (2) the hydroxyl group-containing resin of (1) above. A hydroxyl group and an unsaturated double compound obtained by reacting the glycidyl group-containing unsaturated monomer of (g) above with the carboxyl group of a vinyl copolymer containing a monomer and an unsaturated carboxylic acid as copolymerization components. a resin containing a bond, (1) the hydroxyl group-containing monomer of (I) and (2)
A resin containing a hydroxyl group and an unsaturated double bond obtained by reacting a vinyl copolymer containing an unsaturated monomer containing a glycidyl group as a copolymerization component with an unsaturated carboxylic acid is used.

In the above resins containing hydroxyl groups and unsaturated double bonds, it is preferable that the phase of hydroxyl groups and unsaturated double bonds in one molecule is 3 equivalents or more, and The equivalent ratio of the unsaturated double bond and the unsaturated double bond is 0.
2-0.8: 0.8→, 2 is preferable.

However, there is no problem even if some molecules containing only hydroxyl groups and no unsaturated double bonds or molecules containing only unsaturated double bonds and no hydroxyl groups are mixed.

In the above (B) compound containing an unsaturated double bond and a hydroxyl group, the unsaturated double bond is radically hardened by light or heat, while the hydroxyl group is the above (A).
involved in the termination of cationic polymerization of polyvalent epoxy resins,
-1 = A dense network is formed by the two reactions described below, and a film with excellent impact resistance and scratch resistance is formed.

The blending ratio of the polyvalent epoxy resin (A) and the compound containing an unsaturated double bond and hydroxyl group (B) is based on the total amount of (A) and (B) as 100% by weight.
(A) is in the range of 40 to 90% by weight and B) is in the range of 60 to 10% by weight, more preferably (A) is in the range of 50 to 80% by weight.
(B) is in the range of 20 to 50% by weight. If (A) is less than 40% by weight, the scratch resistance will decrease, and if it exceeds 90% by weight, the photocurability and impact resistance will be insufficient, which is not suitable for the present invention.

In addition to the above components (A) and (B), vinyl monomers such as styrene, paramethylstyrene, methacrylic esters, and acrylic esters, and monoepoxides such as phenyl glycidyl ether and butyl glycidyl ether may also be used. It may be used within a range that does not impede the effects of the present invention.

The doryarylsulfonium complex salt (C) used in the present invention is an initiator for photocationic polymerization, and is involved in photocuring by generating a Lewis acid upon irradiation with light such as ultraviolet rays.

Examples of the triarylsulfonium complex salt (C) include l-liphenylsulfonium hexafluoroantimonate, trinoenylsulfonium tetrafluoroborate, triphenylsulfonium hegisafluorophosphate, tris(4- thiomethoxyphenyl)sulfonium hexafluorophosphate, etc., and doryarylsulfonium hexafluoroane 7-thimonate is particularly preferred from the viewpoint of photocurability and pot life. (A) and ((C) above)
The blending ratio of B) to the total amount is usually n, 2 to 5% by weight, preferably 1 to 3% by weight.

In addition, the triarylsulfonium complex salt (C) is said to act as an initiator for unsaturated double bonds, but since it does not have a sufficient photocuring speed, the radicals cannot be removed by light or heat as described in (D) above. Using generated initiator.

Examples of the initiator (D) that generates radicals by light or heat used in the present invention include benzoins such as benzoin, benzoin methyl ether, benzoin isobutyl ether, benzophenone, 2-
Hydroxy-2-methyl-1-phenyl-propane-1
phenones such as -one, 1=(4-1sopropylphenyl)-2-hydroxy-2-methylpropan-1-one, benzyldimethylketal, 2,2-jetoxyacetophenone, paratertiary-butyltrichloroacetophenone, Anthraquinones such as methylanthraquinone and ethylanthraquinone, thioxanthones such as dimethylthioxane and diisopropylthioxanthone, initiators that generate radicals upon irradiation with light such as Michler's ketone, or for example benzoyl peroxide and lauroyl peroxide. , tertiary-butyl peroxybenzoate, tertiary riftyl hydroperoxide, dicumyl peroxide, cumene hydroperoxide, or azo compounds such as azoisobutyronitrile, azobisvaleronitrile, etc. An initiator that generates radicals is used. An initiator that generates radicals when irradiated with light will generate radicals when irradiated with light such as ultraviolet rays in parallel with the photodecomposition described in (C) above, and an initiator that is decomposed by heat will generate radicals when irradiated with ultraviolet rays. It is decomposed by heat and polymerization heat generated by cationic polymerization, causing crosslinking of the unsaturated groups in the component (B).

Alternatively, the curing reaction may be completed more completely by heating after light irradiation at a temperature of 100 to 200°C.

In the practical use of the photocurable composition of the present invention, for example, titanium oxide, iron oxide, zinc oxide, zinc chromate, strontium chromate, phthalocyanine blue, Fillers such as phthalocyanine IJ-7, calcium carbonate, talc, barium sulfate, mica powder, and glass flakes may be used in combination.

The above-mentioned photocurable composition of the present invention is usually applied to a coated object such as metal to a thickness of about 1 μm to 100 μm, and is applied to a light source that emits wavelengths in the ultraviolet region, such as a mercury lamp, a metal halide lamp, or a carbon arc lamp. It is useful because it can be easily cured by irradiation with light.

Hereinafter, the present invention will be specifically explained with reference to Examples.

Example 1 An esterified product of 60 parts by weight of bisphenol A epoxy resin (manufactured by Yuka Shell Co., Ltd., trade name Epicote 828), 1 mol of trifunctional polypropylene glycol (average molecular weight 672), and 2 mols of acrylic acid (OH content 1. 28 equivalent/
'1000L double bond gold content 2.56 equivalent/1000g
100 parts by weight of trinoenyl sulfonium hexafluoroantimonate and 2 parts by weight of benzoin isobutyl ether were mixed to obtain a photocurable composition (I) of the present invention.

Example 2 40 parts by weight of bisphenol A type epoxy resin (manufactured by Yuka Shell Co., Ltd., trade name Epicote 828), 30 parts by weight of 1.5-bentanediyl diglycidyl ether, and dipentaerythritol triacrylate (OH content: 7.21 equivalents)
/10 G Og, double bond content 7.21 equivalents/'1
000q), 2 parts by weight of trinoenylsulfonium hexafluoroantimonate, and 2 parts by weight of methylanthraquinone were mixed to obtain a photocurable composition (T'I) of the present invention.

Example 3 Alicyclic epoxy resin 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate (trade name manufactured by UCC, ERL-4221) 5
A resin (01 (
Content: 2.55 equivalents/1000 ml, double bond content: 3.
82 equivalents/1000100 O parts by weight and 10 parts by weight of tetraethylene glycol monoacrylate and triphenylsulfonium hexafluoroantimone) 2
Itit part and 2 parts by weight of 2-hydroxy-2-methyl-1-phenyl-propan-1-one were mixed to obtain a photocurable composition (TII) of the present invention.

Example 4 Ring group epoxy resin 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexane carboxylate (UCC company m, H product name E RL-4221) 7
0 parts by weight, 1 mole of fumaric acid, 1 mole of sebacic acid, and 2.5 moles of furopylene gellicol (OH content 2.4 equivalents/'10 (') 0
9. Double bond content 2.3 equivalents/'1000! 7) 20
it t part and hydroxyethyl methacrylate 10
parts by weight, 2 parts by weight of trinoenyl sulfonium hexafluoroantimonate, and 2 parts by weight of tertiary-butyl peroxybenzoate were mixed to obtain a photocurable composition (TV) of the present invention.

Example 5 27.5 parts by weight of bisphenol A type epoxy resin (manufactured by Yuka Shell Co., Ltd., trade name: Pico 815), bis(3,4-epoxy-cyclohexyl) adipe) which is an alicyclic epoxy resin 27. 5 parts by weight, 1 mol of succinic anhydride,
Trimetic anhydride 0.6 mol, hexanediol 1.8
A compound obtained by adding 0.8 moles of glycidyl methacrylate to a polyester containing hydroxyl and carboxyl groups obtained by condensing 2 moles (OH content: 3.2 equivalents/
'10009, double bond content 1.8 equivalent i/1000!
111), 2 parts by weight of triphenylsulfonium hexafluoroandemonate, and 2 parts by weight of benzyl dimethyl ketal were mixed to obtain a photocurable composition (v) of the present invention.

Example 6 40 parts by weight of bisphenol A type epoxy resin (manufactured by Yuka Shell Co., Ltd., trade name Epicote 828) and 3,4-epoxycyclohexylmethyl-3, which is an alicyclic epoxy resin.
4-Epoxycarboxylate (manufactured by UCC, trade name E
RL-4221) 40 parts by weight, butyl acrylate 63.
6% by weight, 13% by weight of hydroxyethyl methacrylate
A compound obtained by reacting an equivalent amount of glycidyl acrylate with acrylic acid and a copolymer consisting of 14.4% by weight of acrylic acid (01-1 content: 2.5g equivalent/'1000
g, double bond content 1.5g equivalent/”1000!7)2
The photocurable composition of the present invention (VT
) was obtained.

Example 7 40 parts by weight of bisphenol A epoxy resin (manufactured by Yuka Shell Co., Ltd., trade name Epicote 828) and alicyclic epoxy resin 3,4-epoxycyclohexylmethyl-
3,4-epoxycyclohexane (3,4-epoxycyclohexane) (
A copolymer consisting of 40 parts by weight of ERL-4221 (manufactured by UCC, trade name), 64.4% by weight of ethyl acrylate, 28.4% by weight of glycidyl methacrylate, and 7.2% by weight of hydroxypropyl methacrylate, and 1% of the glycidyl group
A compound obtained by reacting acrylic acid equivalent to /'2 equivalents (OH content 1.4 equivalents/'1000, double bond content 0.93 equivalents iH/'1000! l') 20 Iit parts,) 2 parts by weight of liphenylsulfonium hexafluoroantimonate and 2 parts by weight of benzyl dimethyl ketal were mixed to obtain a photocurable composition (■) of the present invention.

Example 8 Photocurable compositions (I) to (I) of the present invention obtained in Examples 1 to 7
■) was applied to a 0.5 mm thick galvanized steel plate to a film thickness of 25 μm, and a high-pressure mercury lamp (8 OW/W) was applied.
=) Under 4 lamps (distance between lamp and object is 15c/rL)
), and the passing speed (m7 minutes) at which the stickiness on the surface completely disappears is shown in Table I as the curability.

The impact resistance and scratch resistance at a passing speed of 5 m/min are also shown in Table 3.

Comparative Example] 50 parts by weight of the bisphenol A epoxy resin used in Example 6 (manufactured by Yuka Shell Co., Ltd., trade name Epicote 828),
50 parts by weight of 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate and 2 parts by weight of triphenylsulfonium hexafluoroandemonate were mixed to prepare a photocurable composition (■) as a comparative example.
I got it.

Comparative Example 2 Esterified product of 1 mole of trifunctional polypropylene glycol (average molecular weight 672) shown in Example 1 and 3 moles of acrylic acid 2 parts by weight of benzoin isobutyl ether
Parts by weight were mixed to obtain a photocurable composition (rX) as a comparative example.

Comparative Example 3 60 parts by weight of the bisphenol A epoxy resin used in Example 1 (manufactured by Yuka Shell Co., Ltd., trade name Epicote 828) and trifunctional polypropylene glycol (average molecular weight 672)
) and 2 parts by weight of triphenylsulfonium hexafluoroantisupernate were mixed to obtain a photocurable composition (X) of a comparative example.

Comparative Example 4 Photocurable compositions obtained in Comparative Examples 1 to 3 (Vllll)
~(X) were applied in exactly the same manner as in Example 1,
Light-cured. The evaluation results are listed in Table I.

(Note) *1: Curability was expressed as the passing speed (m/min) of the coated plate under the lamp when the stickiness completely disappeared after photocuring was carried out under the conditions shown in Example 8.

*2: The coating film photocured under the conditions of Example 8 was scratched with a fingernail to determine whether or not scratches were generated on the surface.

*3: Impact resistance was measured by dropping a load of 500 kg using a DuPont impact tester (striking core diameter 1/2 inch) and expressing the drop distance at which cracks occurred on the painted surface.

patent applicant Mitsui Toatsu Chemical Co., Ltd. 19-

Claims (1)

[Claims] 1) (A) 40 to 90% by weight of polyvalent epoxy resin, (B
) 60 to 10% by weight of a compound containing an unsaturated double bond and a hydroxyl group (however, the total amount of (A) and (B) is 100% by weight), (C) ) IJ arylsulfonium complex salt and ( D) A photocurable composition comprising an initiator that generates radicals when exposed to light or heat.