JPH10279616A - Energy-ray-curable composition and cured item thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an energy-ray-curable compsn. which exhibits an excellent curability esp. when it contains a pigment by compounding a cationically polymerizable substance (e.g. an epoxy compd.), a cationically polymerizable sulfonium salt having a specified max. molar absorptivity coefficient at a specified wavelength, and a photo free-radical initiator. SOLUTION: This compsn. contains a cationically polymerizable substance (A), a cationically polymerizable sulfonium salt (B) having a max. molar absorptivity coefficient of 100 or higher at a wavelength range of 360-500 nm, and a photo free-radical polymn. initiator (C). Ingredient A is an epoxy compd., a vinyl compd., an oxetane compd., etc. Ingredient B is a sulfonium salt having a thioxanthone, anthraquinone, or acridone structure. Ingredient C is a benzoin compd., an acetophenone compd., an acylphosphine oxide, etc. The compsn. may further contain a pigment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an energy ray-curable composition and a cured product thereof, and more particularly, to a cationically polymerizable composition which is cured by light irradiation or light irradiation and, if necessary, heat and a cured product thereof. About. Particularly, the present invention relates to an energy ray-curable composition excellent in curability and a cured product thereof even in the case of a composition containing a pigment.

[0002]

2. Description of the Related Art Examples of a catalyst for curing a cationically polymerizable compound such as an epoxy compound by light irradiation and a composition thereof are disclosed in JP-A-50-151997 and JP-A-50-1.
No. 58680 and the like. JP-A-56-152833 and JP-A-58-3700 disclose catalysts for curing cationically polymerizable compounds such as epoxy compounds by heating and compositions thereof.
No. 3, JP-A-63-223002 and the like are known. Further, a catalyst for curing a cationically polymerizable compound such as an epoxy compound by light irradiation and heat and a composition thereof are described in Japanese Patent Publication No. 2-196812.

[0003]

As described above, various studies have been made on compositions containing cationically polymerizable compounds such as epoxy compounds which are cured by light irradiation or light irradiation and, if necessary, heat. However, the curability of the composition containing a pigment is insufficient, and suggestions for improvement are not sufficient. Under such circumstances, as the field of use of the photopolymerizable composition expands, the demand of the market, for example, the provision of a novel composition having a sufficient curing ability even for a composition containing a pigment. Has become an important technical issue.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, in a composition containing a cationic polymerizable substance, the maximum molar extinction coefficient in the wavelength range of 360 to 500 nm was found. By containing a sulfonium salt having a photocationic polymerization initiation ability of 100 or more and a photoradical polymerization initiator, an energy ray-curable composition excellent in curability, particularly in a composition containing a pigment, can be obtained. The inventors have found that the present invention has been completed.

That is, the present invention relates to (1) a cationically polymerizable substance (A) and a sulfonium salt (B) having a photocationic polymerization initiation ability and having a maximum molar extinction coefficient of 100 or more in a wavelength range of 360 to 500 nm. An energy ray-curable composition comprising a radical polymerization initiator (C), (2) the energy ray-curable composition according to (1), wherein the sulfonium salt (B) is a sulfonium salt having a thioxanthone structure, (3) the energy ray-curable composition of (1), wherein the photo-radical polymerization initiator (C) is an acylphosphine oxide compound, and (4) the pigment (D)
(1) to (3), (5) a cured product of the energy ray-curable composition according to any one of (1) to (4), ,
(6) An article having a film made of the cured product according to (5).

The present invention will be described in detail. In the energy ray-curable composition of the present invention, preferred specific examples of the cationically polymerizable substance (A) include, for example, a compound having an epoxy group, a vinyl compound, an oxetane compound,
Spiro orthocarbonate compounds and the like. Specific examples of the compound having an epoxy group that can be used include, for example, bisphenol-type epoxy resin which is a reaction product of bisphenol A such as bisphenol A and bisphenol F with epichlorohydrin, and novolak which is a reaction product of novolak resin such as phenol novolak and epichlorohydrin. Epoxy resin, trisphenolmethane epoxy resin, glycidyl ether compounds such as phenylglycidyl ether, polyglycidyl ether of polyhydric alcohols, and 3,4-epoxycyclohexylmethyl-3,4
-Epoxycyclohexanecarboxylate, bis (3,4-epoxycyclohexyl) adipate, vinylcyclohexene dioxide, 2- [3,4-epoxycyclohexyl-5,5-spiro-3,4-epoxy]
Cyclohexanemetadioxane, 1,2-epoxy-p
-Alicyclic epoxy compounds such as vinylcyclohexene;

Specific examples of usable vinyl compounds include styrenes such as styrene, α-methylstyrene and p-chloromethylstyrene; n-butyl vinyl ether, isobutyl vinyl ether, cyclohexyl vinyl ether, hydroxybutyl vinyl ether, hydroxy Alkyl vinyl ethers such as ethyl vinyl ether; alkenyl vinyl ethers such as allyl vinyl ether and 1-octahydronaphthyl vinyl ether; alkynyl vinyl ethers such as ethynyl vinyl ether and 1-methyl-2-propenyl vinyl ether; and phenyl vinyl ether and p-methoxyphenyl vinyl ether Aryl vinyl ethers; butanediol divinyl ether, triethylene glycol divinyl ether, cyclohexa Alkyl polyvinyl ethers such as diol divinyl ether and trimethylolpropane trivinyl ether; aralkyl divinyl ethers such as 1,4-benzenedimethanol divinyl ether and m-phenylenebis (ethylene glycol) divinyl ether: hydroquinone divinyl ether and resorcinol divinyl ether Aryl divinyl ethers; polyester polyvinyl ethers; polyurethane vinyl ethers and the like.

Further, specific examples of spiro orthocarbonate compounds that can be used include, for example, 1,5,7,11-
Tetraoxaspiro [5,5] undecane, 3,9-dibenzyl-1,5,7,11-tetraoxaspiro [5,5] undecane, and 1,4,6-trioxaspiro [4,4] nonane And spiroorthoester compounds such as 1,2-methyl-1,4,6-trioxaspiro [4,4]) nan and 1,4,6-trioxaspiro [4,5] decane. These cationically polymerizable substances (A)
May be used alone or in combination of two or more. Further, among these cationically polymerizable substances (A), a compound having an epoxy group is particularly preferably used.

The sulfonium salt having a maximum molar extinction coefficient of 100 or more in the wavelength range of 360 to 500 nm, which is the component (B) used in the present invention, acts as a photocationic polymerization initiator and is decomposed by light irradiation. It initiates cationic polymerization. Specific examples of such a cationic photopolymerization initiator include a sulfonium salt having a thioxanthone structure, a sulfonium salt having an anthraquinone structure, and a sulfonium salt having an acridone structure. Among them, a sulfonium salt having a thioxanthone structure includes, for example, the following general formula (1)

[0010]

Embedded image

(Wherein R ₁ and R ₂ each independently represent a hydrogen atom, an alkyl group, a halogen atom, a hydroxyalkyl group or an alkoxy group, and R _{3 to} R ₅ each independently represent a hydrogen atom, a halogen atom, X represents SbF ₆ , PF ₆ or B (C ₆ F ₅ );
₄ respectively. )). Here, examples of the alkyl group include C _{1 to} C ₁₅ alkyl groups such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, and a butyl group. Examples of the halogen atom include F, Cl, Br, I and the like. Examples of the alkoxy group include a C ₁ -C ₅ alkoxy group such as a methoxy group, an ethoxy group, and a butoxy group. The hydroxyalkyl group, e.g., hydroxymethyl group, and a hydroxyalkyl group of C ₁ -C _5, such as hydroxyethyl group. Next, specific examples of the compound represented by the general formula (1) are shown in Table 1.

[0012]

Table 1 Compound No. R ₁ R ₂ R ₃ R ₄ R ₅ X 1-1 —CH ₃ —CH ₃ —H—C ₂ H ₅ —C ₂ H ₅ PF ₆ 1-2 —CH ₃ —CH _{3 -H -C 2 H 5 -C 2 H} 5 SbF 6 1-3 -F -F -H -C 2 H 5 -C 2 H 5 SbF 6 1-4 -CH 3 -CH 3 -H -C 3 H _{7 (iso) -H PF 6 1-5} -F -F -H -C 3 H 7 (iso) -H PF 6 1-6 -F -F -H -C 3 H 7 (iso) -H SbF 6 _{1-7 A A -H -C 3 H 7} (iso) -H PF 6 1-8 -OCH 3 -OCH 3 -H -C 3 H 7 (iso) -H B (C 6 F 5) 4 1- _{9 -H -H -Cl -H -OC 4 H} 9 PF 6 1-10 -H -H -Cl -H -OC 4 H 9 SbF 6 1-11 -F -F -H -Cl -H PF 6 1 _{-12 -F -F -H -Cl -H SbF 6} 1-13 -CH 3 -CH 3 -H -Cl -H PF 6 1-14 _{CH 3 -CH 3 -H -Cl -H B} (C 6 F 5) 4 1-15 -H -H -H -Cl -H PF 6 A = -OC 2 H 4 OH

As the sulfonium salt having an anthraquinone structure, for example, the following general formula (2)

[0014]

Embedded image

(Wherein, R ₆ and R ₇ each independently represent a hydrogen atom, an alkyl group, a halogen atom, a hydroxyalkyloxy group or an alkoxy group, and X represents SbF ₆ , PF
₆ or B (C ₆ F ₅ ) ₄ . )). Here, examples of the alkyl group include C _{1 to} C ₅ alkyl groups such as a methyl group, an ethyl group, an n-propyl group, and a butyl group. Examples of the halogen atom include F, Cl, Br, and I. No. Examples of the alkoxy group include C ₁ groups such as a methoxy group, an ethoxy group, an n-propoxy group, and an isopropoxy group.
Alkoxy group -C ₅ thereof. The hydroxyalkyl group, e.g., hydroxymethyl group, hydroxyethyl group, and a hydroxyalkyl group of C ₁ -C _5, such as hydroxybutyl group. Next, specific examples of the compound represented by the general formula (2) are shown in Table 2.

[0016]

TABLE 2 Compound No. substitution position _{R 6 R 7 X 2-1 1 -CH} 3 -CH 3 PF 6 2-2 1 -CH 3 -CH 3 SbF 6 2-3 1 -F -F SbF 6 2- _{4 1 -F -F PF 6 2-5 1} -F -F B (C 6 F 5) 4 2-6 1 -H -H B (C 6 F 5) 4 2-7 2 -OC 2 H 4 OH -OC ₂ H ₄ OH PF ₆

(Note) The substitution position is a bonding position of a sulfur atom on the anthraquinone skeleton.

Further, as the sulfonium salt having an acridone structure, for example, the following general formula (3)

[0019]

Embedded image

(Wherein R ₈ , R ₁₀ and R ₁₁ are each independently a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group or a hydroxyalkyloxy group, R ₉ is an alkyl group, X is SbF ₆ , PF ₆ or B (C ₆ F ₅ ) _4. ). Here, examples of the alkyl group include C ₁ -C 4 groups such as methyl group, ethyl group, n-propyl group, isopropyl group and t-butyl group.
_{And 5} alkyl groups. As the alkoxy group,
For example, a methoxy group, an ethoxy group, an n-propoxy group,
C ₁ -C ₅ alkoxy groups such as isopropoxy group. As the hydroxyethyloxy group, for example,
Hydroxymethyl group, hydroxyethyl group, and a hydroxyalkyl group of C ₁ -C _5, such as hydroxybutyl group. Examples of the halogen atom include F, Cl, Br, I and the like. Next, specific examples of the compound represented by the general formula (3) are shown in Table 3.

[0021]

[Table 3] Compound No. R₈ R₉ R_Ten R₁₁ X3-1-Cl- (n-C_FourH₉) -F -F SbF₆ 3-2-Cl- (n-C_FourH₉) -F -F PF₆ 3-3-Cl- (n-C_FourH₉) -H -H B (C₆F_Five)_Four 3-4-Cl- (n-C_ThreeH₇) -CH_Three -CH_Three SbF₆ 3-5-Cl- (n-C_ThreeH₇) -CH_Three -CH_Three PF₆ 3-6-Cl- (n-C_FourH₉) -OCH_Three -OCH_Three SbF₆  3-7 -Cl- (n-C_FourH₉) A A PF₆ A = -OC_TwoH_FourOH

The component (B) used in the present invention includes:
In addition to these sulfonium salts, for example, JP-A-8-1
Compounds described in No. 65290 are exemplified. The component (B) used in the present invention has a wavelength of 360.
The maximum molar extinction coefficient in the region of ~ 500 nm is 100
It is preferably at least 1,000, particularly preferably at least 2,000. Wavelength 360-500n
In the case where there is no absorption in the region of m or the molar extinction coefficient is 100 or less, particularly in a composition containing a pigment, there is a problem that the composition does not cure or the curing is delayed.

Preferred examples of these sulfonium salts include, for example, 1-
5, No. 1-6, No. 1-7, no. 1-8, N
o. 1-9, no. 1-10, no. 1-11, No. 1;
Examples thereof include sulfonium salts having a thioxanthone structure such as 1-12.

The photo-radical polymerization initiator (C) used in the present invention is a component that contributes to further improving the curability of the energy ray-curable composition of the present invention. Specific examples of the component (C) include benzoin such as benzoin, benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether, and alkyl ethers thereof; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, and 2,2-diethoxy. -2-phenylacetophenone, 1,1-dichloroacetophenone,
Acetophenones such as 1-hydroxycyclohexylphenyl ketone and 2-hydroxycyclohexylphenyl ketone; anthraquinones such as 2-methylanthraquinone and 2-ethylanthraquinone; 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone and 2-chlorothioxanthone Thioxanthones such as isopropylphenone, 2-isopropylthioxanthone; ketals such as acetophenone dimethyl ketal and benzyldimethyl ketal; benzophenones such as benzophenone; 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, bis (2,6-dimethoxybenzoyl) Acylphosphine oxides such as -2,4,4-trimethylpentylphosphine oxide and the like can be mentioned. Of these, particularly preferred are acylphosphine oxides such as 2,4,6-trimethylbenzoyl-diphenylphosphine oxide and bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide. Can be mentioned.

In the present invention, the pigment (D) is used as an optional component. Specific examples of the pigment (D) that can be used include, for example, the following. ○ black pigment carbon black, acetylene black, run black, aniline black ○ yellow pigment: graphite, zinc yellow, cadmium yellow, yellow iron oxide, mineral fast yellow, nickel titanium yellow, navels yellow, naphthol yellow S, Hansa yellow G, Hansa Yellow 10G, Benzidine Yellow G,
Benzidine yellow GR, Quinoline yellow lake, Permanent yellow NCG, Tartrazine lake ○ Orange pigment Red mouth graphite, Molybdenum orange, Permanent orange GTR, Pyrazolone orange, Vulcan orange, Indaslen brilliant orange RK, Benzidine orange G, Indaslen brilliant orange GK ○ Red pigment Bengala, Cadnium Red, Lead Tan, Mercury Sulfide Cadmium, Permanent Red 4R, Risor Red, Pyrazolone Red, Watching Red Calcium Salt, Lake Red D, Brilliant Carmine 6B, Eosin Lake, Rhodamine Lake B, Alizarin Lake , Brilliant Carmine 3B ○ Purple pigment Manganese purple, Fast Violet B, Methyl Violet Lake ○ Blue pigment Navy blue, Baltic blue, alkali blue lake, Victoria blue lake, phthalocyanine blue, metal-free phthalocyanine blue, phthalocyanine blue, partially chlorinated, Fast Sky Blue, Indus Ren Blue BC ○ green pigment chrome green, chromium oxide, Pigment Green B,
Malachite green lake, Fanal yellow green G ○ White pigment Zinc white, titanium oxide, antimony white, zinc sulfide ○ Constituent pigment Barite powder, barium carbonate, clay, silica, white carbon, talc, alumina white

The content ratio of each component (A) to (D) in the energy ray-curable composition of the present invention is as follows.
In the composition of the present invention, the amount is preferably 34.7 to 99.7% by weight, particularly preferably 49.7 to 99.7% by weight.
The component (B) accounts for 0.3 to 15% by weight in the composition of the present invention.
Is preferred, and particularly preferably 1 to 10% by weight.
Component (C) is preferably 0.01 to 10% by weight, and particularly preferably 0.05 to 5% by weight, in the composition of the present invention. The component (D) is preferably from 0 to 70% by weight, particularly preferably from 10 to 60% by weight.

The energy ray-curable composition of the present invention comprises:
Solvents for dilution and resins for modification (for example, acrylic polymer, polyurethane polymer, polyester elastomer, polyvinyl chloride polymer, acrylonitrile rubber, etc.) as long as polymerization is not impaired, and, for example, to improve electrical properties It is possible to use organic carboxylic acids or acid anhydrides, or to mix polyols or other flexible prepolymers for the purpose of imparting rubber elasticity, and further, dyes, fillers, antistatic agents, flame retardants And additives such as an antifoaming agent, a flow regulator, a light stabilizer, a coupling agent, and an organic solvent.

The energy ray-curable composition of the present invention comprises the components (A) to (D) and, if necessary, other components,
It can be prepared by mixing, dissolving, dispersing and kneading.

The energy ray-curable composition of the present invention has a thickness of usually 1 to 100 μm, preferably 2 to 50 μm on the substrate.
After application so as to obtain a value of m, the film can be cured to a dry state to the touch or a solvent-insoluble state after 0.1 seconds to several minutes by irradiating energy rays such as ultraviolet rays. Examples of the substrate include metal, wood, paper, rubber, plastic, glass, and ceramic products. Examples of the method of applying the energy ray-curable composition of the present invention to a substrate include printing methods such as screen printing and dry offset printing, and methods using a coater such as a roll coater, a spin coater, and a per coater. In curing the energy ray-curable composition of the present invention, the energy ray is obtained from a high-pressure mercury lamp, a low-pressure mercury lamp, a xenon lamp, a metal halide lamp, a germicidal lamp, a laser beam, or the like,
It is preferable to use an energy ray having a wavelength of 200 nm to 500 nm. Exposure to an energy ray depends on the intensity of the energy ray, but usually about 0.1 to 10 seconds is sufficient. However, for relatively thick painted objects,
It is preferable to spend more time. The resin is cured by polymerization 0.1 second to several minutes after the irradiation with the energy beam, but it is preferable to perform heating (for example, 40 to 150 ° C.) during or after the irradiation with the energy beam in order to promote the polymerization reaction.

Specific uses of the energy ray-curable composition of the present invention include, for example, white ink for metal cans such as food cans, various printing inks, paint resist inks, fillers, adhesives and the like. Can be Examples of the article having the cured film of the energy ray-curable composition of the present invention include metal cans such as metal cans such as food cans.

[0031]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. Parts in Examples are parts by weight.

Examples 1 to 3 and Comparative Examples 1 and 2 Compounding and kneading (using a three-roll mill) were carried out according to the composition shown in Table 4 (the numerical values are parts by weight). An energy ray-curable composition was obtained. 10 μm of these energy ray-curable compositions were placed on an aluminum plate.
m with a bar coater, and apply 25 UV rays from a distance of 8 cm with a metal halide lamp (80 w / cm ² ).
It was irradiated with 0 mJ / cm ² and cured. The following tests were conducted on the curability of the prepared composition and the gloss of a cured coating film obtained by curing the composition. Table 4 shows the results.

Curability: After the cured coating film was left for 24 hours, it was rubbed with absorbent cotton impregnated with methyl ethyl ketone, and the number of times until the coating film did not change was measured. Gloss: The surface of the cured coating film was visually judged. A: The gloss is extremely good.・ ・ ・: Good gloss. Δ: There is slight cloudiness. X: No gloss at all.

[0034]

Table 4 Example Comparative Example 12 3 12 2 ○ Composition Composition (A) Component 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate 84 68 84 84 84 Bisphenol A diglycidyl ether 20 (B) Component Compound No. 1-5 33 Compound No. 1-6 3 Compound No. 1-113 (C) component 2,4,6-trimethylbenzoyl-diphenylphosphine oxide 11 1 (D) component titanium dioxide (rutile type) 100 100 100 100 100 Others UVI-6990 * 16 Polyester resin * 2 10 6 10 10 10 Surfactant (L-7604) * 3 0.4 0.4 0.4 0.4 0.4 ○ Physical properties Curability (number of rubbing) 100 times 100 times 100 times 5 times 1 time or more Gloss ○ ○ ○ ○ ×

(Note) * 1 UVI-6990: a cationic cationic polymerization initiator manufactured by Union Carbide Co., Ltd. Propylene carbonate 50% diluted product, no absorption at a wavelength of 360 nm or more. * 2 Polyester resin: “Byron 20” manufactured by Toyobo
0 "Molecular weight 2000-3000. * 3 L-7604: manufactured by Nippon Unicar, a surfactant. * 4 Compound No. 1-5: Photocationic polymerization initiator, molar extinction coefficient 5000 at a wavelength of 384 nm. * 5 Compound No. 1-6: Photocationic polymerization initiator, molar extinction coefficient 5090 at a wavelength of 382 nm. * 6 Compound No. 1-11: Photocationic polymerization initiator,
Molar extinction coefficient 4580 at a wavelength of 387 nm.

As is clear from the results shown in Table 4, the composition of the present invention has excellent curability by ultraviolet rays even in a composition containing a pigment, and the obtained cured product has excellent gloss and the like.

[0037]

The energy ray-curable composition of the present invention comprises:
It comprises a sulfonium salt (B) having a cationic photopolymerization ability and a photoradical polymerization initiator (C) having a maximum molar extinction coefficient of 100 or more in a wavelength range of 360 to 500 nm, and has excellent curability. However, the cured product is excellent in physical properties such as gloss. In particular, even when the energy ray-curable composition of the present invention contains a pigment,
Excellent curability, gloss, etc.

Claims (6)

[Claims] 1. A cationic polymerizable substance (A) having a wavelength of 360 to 360.
An energy ray-curable composition comprising a sulfonium salt (B) having a photocationic polymerization ability having a maximum molar extinction coefficient of 100 or more in a 500 nm region and a photoradical polymerization initiator (C). 2. The energy ray-curable composition according to claim 1, wherein the sulfonium salt (B) is a sulfonium salt having a thioxanthone structure. 3. The energy ray-curable composition according to claim 1, wherein the photo-radical polymerization initiator (C) is an acylphosphine oxide compound. 4. The energy ray-curable composition according to claim 1, further comprising a pigment (D). 5. A cured product of the energy ray-curable composition according to any one of claims 1 to 4. 6. An article having a film comprising the cured product according to claim 5.