JP3251608B2 - Method for producing urethane (meth) acrylate oligomer and photocurable resin composition using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a urethane (meth) acrylate oligomer or a mixture of urethane (meth) acrylate oligomers and a photocurable resin composition using the oligomer or the oligomer mixture.

[0002]

2. Description of the Related Art Conventionally, a photocurable resin composition is applied to the surface of various substrates such as plastics and cured by irradiation with ultraviolet rays to improve the fragility which is a drawback of plastics.
The photo-curable resin composition was mainly composed of a polyester (meth) acrylate oligomer, a polyether (meth) acrylate oligomer, a urethane (meth) acrylate oligomer, etc., and was compounded with various (meth) acrylate monomers and a photopolymerizable initiator. Things are used. Of these, urethane (meth) acrylate oligomers include isocyanates having two or three isocyanate groups in a molecule such as tolylene diisocyanate, hexamethylene diisocyanate, isocyanurate of isophorone diisocyanate, and hydroxyethyl (meth). ) And a hydroxyl-containing (meth) acrylate monomer having 1 to 3 (meth) acryloyloxy groups such as acrylate and pentaerythritol tri (meth) acrylate. Also, isocyanates having two or three isocyanate groups in a molecule such as tolylene diisocyanate, hexamethylene diisocyanate, isocyanurate of isophorone diisocyanate and ethylene glycol, propylene glycol,
In some cases, a urethane (meth) acrylate oligomer is obtained by reacting a hydroxyl group-containing acrylate monomer with a urethane prepolymer obtained by reacting with an alcohol having two hydroxyl groups in a molecule such as 1,6-hexanediol.

[0003]

However, when a photo-curable resin composition containing these urethane (meth) acrylate oligomers is applied and then photo-cured, the curability, hardness, internal cohesion, and adhesion are reduced. At present, satisfactory physical properties have not been obtained.

[0004]

The inventors of the present invention have conducted intensive studies and have found that various photo-curable resin compositions containing a specific urethane (meth) acrylate oligomer as an essential component are applied to various substrates and irradiated with ultraviolet rays. It was found that when cured, the composition exhibited excellent curability and cured physical properties, and the present invention was completed.

The present invention relates to [A] (a) isocyanates having three or more isocyanate groups in the molecule, and (b) polyisocyanates having at least one hydroxyl group and at least two (meth) acryloyloxy groups in the molecule. A urethane (meth) acrylate oligomer or a urethane (meth) acrylate oligomer mixture obtained by reacting a functional (meth) acrylate and a polyhydric alcohol having at least two hydroxyl groups in the molecule (c) are essential components. Accordingly, a photocurable resin composition obtained by blending one or more monomers copolymerizable with the urethane (meth) acrylate oligomer or the urethane (meth) acrylate oligomer mixture, and [B] the (a) Isocyanates, polyfunctional (meth) acrylates of (b) and A method for producing a urethane (meth) acrylate oligomer or a urethane (meth) acrylate oligomer mixture comprises reacting the polyhydric alcohols of the (c).

Hereinafter, the contents of the present invention will be described in detail. Isocyanates having 3 or more isocyanate groups in the molecule can be used alone or two or more, triphenylmethane triisocyanate specific examples, dimethylene triphenyl triisocyanate, the following formulas 13
And a compound represented by the following chemical formula 14 .

[0007]

(Wherein R is a compound represented by the following formulas 15 , 16 and 17)
Or an organic group represented by Chemical Formula 18 ).

[0008]

Embedded image (Wherein, R represents the following chemical formula 15 , chemical formula 16 , chemical formula 17 or chemical formula 1)
And the organic group represented by 8 ).

[0009]

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[0010]

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[0011]

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[0012]

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[0013] The compounds represented by Formula 13 and Formula 14, (which is an organic group of R is of 15 In formula 13 compound) respectively isocyanurate of isophorone diisocyanate, the isocyanurate body (of 13 of hexamethylene diisocyanate compound R is an organic group of 16), the compound is an organic group of R is of 17 in isocyanurate (of 13 tolylene diisocyanate), R is of the isocyanurate (of 13 methylene bis cyclohexyl diisocyanate 18 is an organic group of compounds), and the compound is an organic group of R is of 15 in biuret (of 14 isophorone diisocyanate), is an organic group of R is of 16 in biuret (Formula 14 of hexamethylene diisocyanate Compounds) and the like That. Suitable isocyanates having three or more isocyanate groups in the molecule include isocyanurate of isophorone diisocyanate, isocyanurate of hexamethylene diisocyanate, biuret of isophorone diisocyanate and biuret of hexamethylene diisocyanate.

One or more polyfunctional (meth) acrylates having at least one hydroxyl group and at least two (meth) acryloyloxy groups in the molecule can be used. Specific examples thereof include trimethylolpropane di (meth) acrylate, ditrimethylolpropane di (meth) acrylate, ditrimethylolpropane tri (meth) acrylate, glycerin di (meth) acrylate, pentaerythritol di (meth) acrylate, and pentaerythritol Tri (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, polypentaerythritol poly (meth) acrylate, etc., among which trimethylolpropane diacrylate, ditrimethylolpropane triacrylate , Pentaerythritol triacrylate,
Dipentaerythritol pentaacrylate and polypentaerythritol polyacrylate are preferred.
Commercially available polyfunctional (meth) acrylates having at least one hydroxyl group and at least two (meth) acryloyloxy groups in the molecule usually contain a full ester corresponding to the polyfunctional (meth) acrylate. I have. Since this full ester does not adversely affect the production method and the photocurable resin composition of the present invention, the commercially available product has at least one hydroxyl group and at least two (meth) acryloyloxy groups in the molecule. It can be used as polyfunctional (meth) acrylates. Examples of the full ester include trimethylolpropane tri (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, glycerin tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, and dipentaerythritol hexa (meth) acrylate. Can be

One or more polyhydric alcohols having at least two hydroxyl groups in the molecule can be used. Specific examples include ethylene glycol,
Diethylene glycol, propylene glycol, dipropylene glycol, 1,4-butanediol, 1,6-
Hexanediol, glycerin, trimethylolpropane, ditrimethylolpropane, neopentyl glycol, spiroglycol, 2-methyl-2-butyl-1,
3-propanediol, pentaerythritol, dipentaerythritol, polypentaerythritol, neopentylglycol monohydroxypivalate monoester, and the like, among which trimethylolpropane, ditrimethylolpropane, glycerin, pentaerythritol, dipentaerythritol and polypentaner Erythritol is preferred.

Isocyanates having three or more isocyanate groups in the molecule (hereinafter referred to as isocyanates)
Polyfunctional (meth) acrylates having at least one hydroxyl group and at least two (meth) acrylate groups in the molecule (hereinafter referred to as hydroxyl group-containing polyfunctional (meth) acrylates); and at least two hydroxyl groups in the molecule. Regarding the reaction with polyhydric alcohols (hereinafter referred to as polyhydric alcohols), it is also possible to react isocyanates with polyhydric alcohols first and then react with hydroxyl group-containing polyfunctional (meth) acrylates. After reacting isocyanates with hydroxyl-containing polyfunctional (meth) acrylates first and then reacting with polyhydric alcohols, the mixture of polyhydric alcohols and hydroxyl-containing polyfunctional (meth) acrylates It may be reacted with isocyanates. When the reaction is carried out using at least one of isocyanates, hydroxyl-containing polyfunctional (meth) acrylates and polyhydric alcohols with two or more compounds, two or more urethanes are obtained as reaction products. A mixture of (meth) acrylate oligomers is obtained.

Isocyanate group 1 in isocyanates
The total hydroxyl group of the hydroxyl group in the polyhydric alcohol and the hydroxyl group in the hydroxyl group-containing polyfunctional (meth) acrylate relative to the equivalent is 0.9 to 1.8 equivalents, preferably 1.0 to 1.8 equivalents.
1.5 equivalents are better, and more preferably 1.1 to 1.3.
Good equivalent. When the total hydroxyl group equivalent is less than 0.9 equivalent, the amount of isocyanate groups remaining in the reaction product increases,
The stability as a resin composition tends to deteriorate. If the amount exceeds 1.8 equivalents, the cured physical properties tend to deteriorate.

The molar ratio of the hydroxyl group-containing polyfunctional (meth) acrylate to the polyhydric alcohol is preferably from 5 to 15 mol, and more preferably from 8 to 12 mol, per mol of the polyhydric alcohol. When the amount of the hydroxyl group-containing polyfunctional (meth) acrylate is less than 5 moles per mole of the polyhydric alcohol, gelation may occur during the reaction, or sufficient curability may not be obtained even without gelling during the reaction. It is in. On the other hand, if it exceeds 15 mol, the cured physical properties tend to deteriorate.

The reaction is usually carried out at 40 ° C. to 80 ° C. for 3 hours to 25 hours.
Done in time. In order to promote the reaction, an amine or tin compound generally used in urethane synthesis may be used.
Further, a polymerization inhibitor generally used as a radical polymerization inhibitor such as hydroquinone, hydroquinone monomethyl ether, and p-tert-butylcatechol may be added. Solvents inert to the reaction during the reaction, such as toluene, xylene, ethyl acetate, butyl acetate, acetone,
Methyl ethyl ketone, methyl isobutyl ketone and the like are usually used.

The urethane (meth) thus obtained
When an acrylate oligomer or a urethane (meth) acrylate oligomer mixture is an essential component, and if necessary, one or more monomers copolymerizable with the urethane (meth) acrylate oligomer or the urethane (meth) acrylate oligomer mixture are blended. ,
The photocurable resin composition of the present invention is obtained. Examples of the monomers include the above-mentioned full esters, hydroxyl-containing polyfunctional (meth) acrylates, tetrahydrofurfuryl (meth)
Acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate,
Cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, phenoxy-2-hydroxypropyl (meth) acrylate, N-vinylpyrrolidone, styrene, acrylonitrile, vinyl acetate, acrylamide, 1,4-butanediol di (meth) acrylate 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate,
Examples include spiroglycol di (meth) acrylate, isobornyl di (meth) acrylate, and bisphenol A type epoxy (meth) acrylic acid adduct. When the monomers are blended, curability, hardness and the like are improved. The compounding amount is usually 65 to 300 parts by weight based on 100 parts by weight of the urethane (meth) acrylate oligomer.

The reaction solution obtained according to the above-mentioned production method after the reaction is substantially free of isocyanates and polyhydric alcohols, but is unreacted together with the urethane (meth) acrylate oligomer of the product. It may contain hydroxyl group-containing polyfunctional (meth) acrylates and / or the above-mentioned full ester. Unreacted hydroxyl group-containing polyfunctional (meth) acrylates and full esters do not adversely affect the curability and cured properties of the photocurable resin composition of the present invention even when incorporated into the photocurable resin composition of the present invention. A reaction solution containing polyfunctional (meth) acrylates and / or the above-mentioned full ester can be used as it is in the photocurable resin composition of the present invention.

When the photocurable resin composition of the present invention is cured by ultraviolet irradiation, a photopolymerization initiator is usually added. Benzoin, benzoin ethyl ether, benzoin butyl ether, benzoin isopropyl ether, 2-hydroxy-2-methyl-
1-phenylpropan-1-one, 1-hydroxycyclohexylphenyl ketone, benzophenone, benzyl, benzyldimethylketal, 2,2-diethoxyacetophenone, xanthone, thioxanthone, azobisisobutyronitrile, benzoyl peroxide, and other generally known compounds Photopolymerization initiators. The amount of the photopolymerization initiator is preferably 0.01 to 10 parts by weight, and more preferably 1 to 7 parts by weight, based on 100 parts by weight of the photocurable resin component. When the amount of the photopolymerization initiator is less than 0.01 part by weight, the curing becomes insufficient, and when the amount exceeds 10 parts by weight, a problem such as coloring of the cured film occurs. Further, the photocurable resin composition of the present invention can also be cured by electron beam. In this case, a photopolymerization initiator is unnecessary.

The photocurable resin composition of the present invention may contain a solvent. Examples of the solvent include alcohols such as ethanol, propanol, isopropanol and butanol, aromatic hydrocarbons such as toluene and xylene, acetates such as ethyl acetate and butyl acetate, acetone,
Ketones such as methyl ethyl ketone and methyl isobutyl ketone, 2-ethoxyethanol (hereinafter, referred to as ethyl cellosolve), 2-butoxyethanol (hereinafter, referred to as butyl cellosolve), 2-methoxyethanol (hereinafter, referred to as
Ethers such as methylcellosolve) and 1,4-dioxane.

The photocurable resin composition of the present invention may further comprise additives such as a surface modifier, a light stabilizer, an antioxidant, and an ultraviolet absorber, and, if necessary, an inorganic matting agent such as fine powder silica. A matting material of a material or fine particles such as polyethylene, polycarbonate, polystyrene, and acrylic may be blended.

Further, since the photocurable resin composition of the present invention has a high internal cohesive force, it is coated on a non-release treated surface of a film such as a polyester film or a polyethylene film which has been subjected to a release treatment on one side, and is wound into a roll. Is pressed against the surface of the acrylic plate while rolling the roll during extrusion molding of acrylic resin, for example, and is irradiated with ultraviolet light through the film.
When applied to the so-called transfer method, after which the film is peeled off, the phenomenon in which the photocurable resin composition sticks to the release surface of the film during roll development does not occur, and smooth peeling can be performed, and therefore, after ultraviolet irradiation. It was found that the coating appearance was extremely good and the cured physical properties were satisfactory.

Known methods such as a roll coating method, a spray coating method, a curtain coating method, a dip coating method, and a spin coating method can be applied to the method for coating the photocurable resin composition of the present invention. The photocurable resin composition of the present invention can be applied to various substrates such as plastic, metal, wood, paper, ceramic, and glass.

[0027]

EXAMPLES The present invention will be described below with reference to specific examples, but these are merely examples and the present invention is not limited to these examples. Example 1 1 equipped with a reflux condenser, stirrer, thermometer and dropping funnel
l In a four-necked flask, isocyanurate of hexamethylene diisocyanate (Sumidur N-3500 manufactured by Sumitomo Bayer Urethane Co., NCO content: 21.6%) 9
7.2 g (NCO: 0.5 equivalent), 211 g of toluene and 0.3 g of dibutyltin dilaurate were added, and the temperature was raised to 60 ° C. with stirring. When the temperature reaches 60 ° C., 201.3 g (OH: 0.45 equivalent) of commercially available pentaerythritol acrylate (containing pentaerythritol triacrylate and pentaerythritol tetraacrylate in a weight ratio of 67% and 33%, respectively) from the dropping funnel.
Was added dropwise over 2 hours, and then kept at the same temperature for 4 hours. Further, 7.2 g of trimethylolpropane (O
H: 0.16 equivalent) dissolved in 113 g of ethyl acetate was added dropwise over 2 hours, and then kept at the same temperature for 6 hours to obtain a solid content of urethane acrylate oligomer (hereinafter referred to as oligomer A) and pentaerythritol tetraacrylate of 48. A reaction solution of 0.6% by weight was obtained. GPC analysis of this reaction solution did not detect any isocyanurate of pentaerythritol triacrylate or hexamethylene diisocyanate. In addition, only the trace amount of trimethylolpropane was detected.

Example 2 Using the same reaction vessel as in Example 1, 246 g (OH: 0.55 equivalent) of commercially available pentaerythritol acrylate and 6.7 g of trimethylolpropane, which are the same as those used in Example 1 (OH: 0.15 equivalent), 0.15 g of dibutyltin dilaurate and 253 g of toluene were added,
The temperature was raised to 60 ° C. while stirring. When it reaches 60 ° C,
Isocyanurate of hexamethylene diisocyanate (Sumidur N-3500) 116.6 from the dropping funnel.
g (NCO: 0.6 equivalent) and 116 g of toluene
And then kept at the same temperature for 10 hours, and urethane acrylate oligomer (hereinafter referred to as oligomer B)
And a reaction solution of pentaerythritol tetraacrylate having a solid content of 50% by weight. GPC analysis of this reaction solution showed that pentaerythritol triacrylate, the isocyanurate of hexamethylene diisocyanate, and trimethylolpropane were not detected.

Example 3 Using the same reaction vessel as in Example 1, an isocyanurate of isophorone diisocyanate (Desmodur Z-4370 manufactured by Sumitomo Bayer Urethane, NCO content: 1)
210.5 g (NCO: 0.1%, concentration: 70%)
58 equivalents), 258 g of toluene and 0.45 g of dibutyltin dilaurate, and the mixture was heated to 60 ° C. with stirring. When the temperature reached 60 ° C., 226.2 g (OH: 0.51 equivalent) of the same commercially available pentaerythritol acrylate as that used in Example 1 was added dropwise from the dropping funnel over 2 hours, and then at the same temperature for 4 hours. Insulated. Further, 6.6 g of trimethylolpropane (OH: 0.1
5 equivalents) and 107.5 g of ethyl acetate were added dropwise over 2 hours, and then kept at the same temperature for 6 hours to give a reaction solution containing 47% by weight of a solid content of a urethane acrylate oligomer (hereinafter referred to as oligomer C) and pentaerythritol tetraacrylate. Obtained. GPC analysis of this reaction solution showed that pentaerythritol triacrylate, the isocyanurate of isophorone diisocyanate, and trimethylolpropane were not detected.

Example 4 Using the same reaction vessel as in Example 1, the same commercially available acrylate of pentaerythritol as used in Example 1 (259.9 g, OH: 0.58 equivalent), trimethylolpropane 6 6.6 g (OH: 0.15 equivalent), 0.45 g of dibutyltin dilaurate and 166.4 g of toluene
Was added and the temperature was raised to 60 ° C. while stirring. When the temperature reaches 60 ° C., an isocyanurate of isophorone diisocyanate (Desmodur Z-4370) 22 is added through a dropping funnel.
8.6 g (NCO: 0.63 equivalent) and toluene 20
0 g was added dropwise over 2 hours and then kept at the same temperature for 13 hours to obtain a reaction liquid having a solid content of 49.5% by weight composed of urethane acrylate oligomer (hereinafter referred to as oligomer D), pentaerythritol tetraacrylate and pentaerythritol triacrylate. Was. G
As a result of PC analysis, no isocyanurate of isophorone diisocyanate and trimethylolpropane were detected.

Example-5 In Example-4, instead of the isocyanurate of isophorone diisocyanate, the biuret of hexamethylene diisocyanate (Sumitomo Bayer Urethane Co., Ltd., Sumidur N-75MX, NCO content: 16.5%, concentration: (75%) A urethane acrylate oligomer was prepared in the same manner as in Example 4 except that 160.3 g (NCO: 0.63 equivalent) was used, and the amounts of toluene and dibutyltin dilaurate were changed to 260 g and 0.15 g, respectively. (Hereinafter referred to as oligomer E), a reaction solution containing pentaerythritol tetraacrylate and pentaerythritol triacrylate at a solid content of 50% by weight was obtained. GPC analysis of this reaction solution did not detect any biuret of hexamethylene diisocyanate or trimethylolpropane.

Example-6 A urethane acrylate oligomer (hereinafter referred to as oligomer F) was prepared in the same manner as in Example-4 except that 4.6 g (OH: 0.15 equivalent) of glycerin was used instead of trimethylolpropane. Pentaerythritol tetraacrylate and pentaerythritol triacrylate with a solid content of 49.4% by weight. GPC analysis of the reaction mixture showed no isocyanurate of isophorone diisocyanate or glycerin.

Example -7 A commercially available acrylate of pentaerythritol (containing 67% and 33% by weight of pentaerythritol triacrylate and pentaerythritol tetraacrylate, respectively) in the same reaction vessel as in Example 1 20
1.3 g (OH: 0.45 equivalent), 7.2 g (OH: 0.16 equivalent) of trimethylolpropane, 0.25 g of dibutyltin dilaurate and 211 g of toluene were added, and the temperature was raised to 60 ° C. with stirring. When the temperature reached 60 ° C., 48.6 g of an isocyanurate form of isophorone diisocyanate (Desmodur Z-4370) was added through a dropping funnel.
CO: 0.25 equivalent), biuret of hexamethylene diisocyanate (Sumidur N-75MX)
6 g (NCO: 0.25 equivalent) and 113 g of toluene
Was added dropwise over 2 hours, and then kept at the same temperature for 8 hours to obtain a reaction solution having a solid content of 47.5% by weight composed of urethane acrylate oligomer (hereinafter referred to as oligomer G), pentaerythritol tetraacrylate and pentaerythritol triacrylate. . GPC analysis of this reaction solution showed no isocyanurate form of isophorone diisocyanate, the biuret form of hexamethylene diisocyanate, or trimethylolpropane.

Comparative Example 1 In Example 2, the isocyanurate of hexamethylene diisocyanate was changed to 50.5 g of hexamethylene diisocyanate (NCO: 0.6 equivalent), and the amounts of toluene and dibutyltin dilaurate were changed to 5 respectively.
A reaction solution containing a urethane acrylate oligomer (hereinafter referred to as oligomer H) and pentaerythritol tetraacrylate having a solid content of 50% by weight was obtained in the same manner as in Example 2 except that the amounts were 0.5 g and 0.08 g. GPC analysis of this reaction solution showed that pentaerythritol triacrylate, hexamethylene diisocyanate and trimethylolpropane were not detected.

Comparative Example 2 In Example 2, the isocyanurate of hexamethylene diisocyanate was replaced with isophorone diisocyanate 6
6.7 g (NCO: 0.6 equivalent), and the amounts of toluene and dibutyltin dilaurate used were 67
A reaction liquid having a solid content of 50% by weight comprising a urethane acrylate oligomer (hereinafter, referred to as oligomer I) and pentaerythritol tetraacrylate was obtained in the same manner as in Example 2 except that g and 0.3 g were used. GPC analysis of this reaction solution showed that pentaerythritol triacrylate, isophorone diisocyanate, and trimethylolpropane were not detected.

Comparative Example 3 259.9 g (OH: 0.58 equivalent) of the same commercially available pentaerythritol acrylate as used in Example 1 and dibutyltin dilaurate 0 in the same reaction vessel as in Example 4 .45 g and 166.4 g of toluene were added, and the temperature was raised to 60 ° C. while stirring. When the temperature reached 60 ° C., an isocyanurate form of isophorone diisocyanate (Desmodur Z-4370) was added through a dropping funnel.
5 g (NCO: 0.58 equivalent) and 200 g of toluene
Was added dropwise over 2 hours and then kept at the same temperature for 2 hours to obtain a reaction solution composed of a urethane acrylate oligomer (hereinafter referred to as oligomer J) and pentaerythritol tetraacrylate with a solid content of 48.7% by weight. GPC analysis of this reaction solution did not detect any isocyanurate of pentaerythritol triacrylate or isophorone diisocyanate. After 6.6 g (OH: 0.15 equivalent) of trimethylolpropane was added to the obtained reaction solution, the mixture was stirred at the same temperature for 1 hour to obtain a mixture (referred to as mixture K).

Comparative Example 4 316.7 g (OH: 0.70 equivalent) of the same commercially available pentaerythritol acrylate as used in Example 1 and dibutyltin dilaurate in the same reaction vessel as in Example 1 were used. 6 g and 400 g of toluene were added, and the temperature was raised to 60 ° C. while stirring. When the temperature reached 60 ° C., 210.5 g of an isocyanurate form of isophorone diisocyanate (Desmodur Z-4370) was added through a dropping funnel.
(NCO: 0.58 equivalents) was added dropwise over 2 hours, and then kept at the same temperature for 2 hours to obtain a reaction solution containing a urethane acrylate oligomer (hereinafter referred to as oligomer L) and pentaerythritol tetraacrylate with a solid content of 50% by weight. Was. GPC analysis of this reaction solution did not detect any isocyanurate of isophorone diisocyanate.

Examples -8 to 16 and Comparative Examples -5 to 11 Reaction solutions containing oligomers A to J and L and oligomer J obtained in Examples -1 to 7 and Comparative Examples -1 to 4 were prepared. Mixture K was converted to urethane (meth) as shown in Table 1.
Monomers 40 copolymerizable with acrylate oligomer
Parts by weight and 1 part by weight of the photoinitiator shown in Table 1,
Each photocurable resin composition was obtained. These photocurable resin compositions were cured under the following coating conditions, drying conditions, and ultraviolet irradiation conditions, respectively. Table 1 shows the results (curability, adhesion, and appearance). The amount of each reaction solution and mixture K was 60 parts by weight in terms of solid content.

(Coating conditions)-Coating method: using bar coat method # 8 bar coater-Base material: PMMA extruded plate (Drying condition) Using far-infrared dryer-Drying temperature: 60 ° C-Drying time: 3 minutes (UV irradiation conditions) ultraviolet lamp: 80W / cm, 1 lamp, irradiation distance: 15cm-conveying speed: 2m / min irradiation energy: 0.5J / cm ² (provided that when the curing test, 0.1 J / cm ² Met)

[0040]

[Table 1]

Note) DPE6A: Kayarad DPHA (dipentaerythritol hexaacrylate) manufactured by Nippon Kayaku Co., Ltd. PE3A: Kayarad PET-30 (pentaerythritol triacrylate) manufactured by Nippon Kayaku Co., Ltd. TMP3A: Biscoat 295 manufactured by Osaka Organic Chemical Industry Co., Ltd. (Trimethylolpropane triacrylate) I-184: Irgacure-184 (1-hydroxycyclohexyl phenyl ketone) manufactured by Ciba Geigy BzP: Benzophenone (Evaluation item) Curability: The presence or absence of curing of the coating film is examined. Those that cure are marked with 〇, and those that do not cure are marked with x (the same applies hereinafter).・ Adhesiveness: 100 cut lines of 1 mm are made by inserting 11 cut lines of the coating film reaching the substrate at 1 mm intervals in the coating film, and cellophane tape is stuck on it and rapidly peeled off. After repeating the operation of the cellophane tape at the same location three times, the number of stitches not peeled off is indicated.・ Appearance: Check for cracks, yellowing, whitening, etc.

Examples 17 to 23 and Comparative Examples 12 to
16 The reaction solution or mixture K containing the oligomers A to J and L and the oligomer J obtained in Examples -1 to 7 and Comparative examples -1 to 4 was used as urethane (meth) shown in Table 2.
Monomers 50 copolymerizable with acrylate oligomer
Parts by weight and 5 parts by weight of the photoinitiator shown in Table 2,
Each photocurable resin composition was obtained. Each of these photocurable resin compositions is coated on a non-release treated surface of a polyethylene film subjected to a single-side release treatment with a bar coater (# 8), dried at 70 ° C. for 1 minute, and pressed on an acrylic extruded plate. After that, the film was further set at 70 ° C. for 10 minutes and then cured by irradiation with ultraviolet rays. Table 2 shows the results (curability, adhesion, SW hardness). The amount of each reaction solution and mixture K was 50 parts by weight in terms of solid content.
In addition, after the coated film was dried, a release test was performed after the release-treated polyester film was overlaid. Table 2 shows the results. The photocurable resin compositions (Examples 17 to 23) using the oligomers (A to G) having strong internal cohesion had better peelability and cured physical properties.

[0043]

[Table 2]

The appearances of Examples 17 to 23 were all good. (Evaluation items) Curability: The presence or absence of curing of the coating film is examined.・ Adhesiveness: 11 cut lines of the coating film reaching the substrate at 1 mm intervals are inserted into the coating film at 11 mm intervals each to make 100 stitches of 1 mm, and cellophane tape is stuck on it and rapidly peeled off. After repeating the operation of the cellophane tape at the same location three times, the number of stitches not peeled off is indicated. SW hardness: Using # 0000 steel wool, count the number of scratches when rubbing 10 reciprocations under a load of 1 kg. A: No scratch, B: 1 to 10, C: 11 to 30, D: 31 or more-Peelability: Coat the non-release treated surface of the polyester film with a bar coater (# 8) and dry. After that, the release-treated polyester film is overlaid and pressed, and then slowly peeled off. When the coat layer does not adhere to the release treated surface, it is rated as ○, and when it adheres to the release treated surface and the coat layer is cleaved, it is rated as x.・ Appearance: Check for cracks, yellowing, whitening, etc.

[0045]

When the urethane (meth) acrylate oligomer obtained by the production method of the present invention is used as a photocurable resin composition, a cured product having excellent curability and excellent cured properties can be obtained. Since the photocurable resin composition of the present invention contains such an oligomer, it is an excellent plastic surface protective coating agent. Also, it is excellent in suitability as a UV coating agent for transfer.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-115213 (JP, A) JP-A-59-179619 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08G 18/00-18/87 C08F 290/06

Claims (14)

(57) [Claims] 1. A polyfunctional (meth) acrylate having (a) an isocyanate having three or more isocyanate groups in a molecule, and (b) a polyfunctional (meth) acrylate having at least one hydroxyl group and at least two (meth) acryloyloxy groups in a molecule. And (c) polyhydric alcohols having at least two hydroxyl groups in the molecule, and polyhydric alcohols having at least two hydroxyl groups in the molecule.
Reduce the number of hydroxyl groups in the molecule per mole of the polyhydric alcohol
And at least two (meth) acryloyloxy groups
5 to 15 moles of polyfunctional (meth) acrylates
Urethane (meta) characterized by using and reacting
A method for producing an acrylate oligomer or a urethane (meth) acrylate oligomer mixture. 2. Polyhydric alcohols having at least two hydroxyl groups in the molecule, at least one hydroxyl group in the molecule and at least two (meth) acryloyloxy groups in the molecule.
Total hydroxyl groups of the polyfunctional (meth) hydroxyl group of acrylates having number is, it 0.9-1.8 is equivalent to isocyanate groups 1 equivalent of isocyanate in having three or more isocyanate groups in the molecule Claim 1 characterized by the following:
The manufacturing method as described. 3. An isocyanate having three or more isocyanate groups in a molecule is represented by the following formula: (Wherein, R represents an organic group represented by the following Chemical Formula 3, Chemical Formula 4, Chemical Formula 5 or Chemical Formula 6) and a compound represented by the following formula: 2. The method according to claim 1, wherein R is at least one selected from compounds represented by the following chemical formulas 3, 4, 5, or 6. 6. Embedded image Embedded image Embedded image Embedded image 4. A compound represented by the formula 1 is an isocyanurate of isophorone diisocyanate (R 1
Is an organic group of formula 3), an isocyanurate of hexamethylene diisocyanate (a compound in which R is an organic group of formula 4), and an isocyanurate of tolylene diisocyanate (in which R is At least one compound selected from the group consisting of an organic group compound) and an isocyanurate of methylenebiscyclohexyl diisocyanate (a compound in which R is an organic group of formula 6).
4. The method according to claim 3, wherein the number is at least one species. 5. The compound represented by the formula (2) is a biuret of isophorone diisocyanate (wherein R is a compound of the formula (3))
4. The method according to claim 3, wherein the compound is at least one selected from the group consisting of a compound represented by the formula (1) and a biuret of hexamethylene diisocyanate (compound represented by the formula (2) wherein R is an organic group represented by the formula (4)). 6. Polyfunctional (meth) acrylates having at least one hydroxyl group and at least two (meth) acryloyloxy groups in the molecule are pentaerythritol tri (meth) acrylate and dipentaerythritol penta (meth) acrylate. The method according to any one of claims 1 to 5, which is at least one selected from trimethylolpropane di (meth) acrylate, ditrimethylolpropane tri (meth) acrylate and polypentaerythritol poly (meth) acrylate. 7. The polyhydric alcohol having at least two hydroxyl groups in the molecule is at least one selected from trimethylolpropane, ditrimethylolpropane, glycerin, pentaerythritol, dipentaerythritol and polypentaerythritol. Item 1
7. The method according to any one of items 1 to 6, above. 8. (a) isocyanates having three or more isocyanate groups in the molecule, (b) polyfunctional (meth) acrylate having at least one hydroxyl group and at least two (meth) acryloyloxy groups in the molecule. And (c) polyhydric alcohols having at least two hydroxyl groups in the molecule, and polyhydric alcohols having at least two hydroxyl groups in the molecule.
Reduce the number of hydroxyl groups in the molecule per mole of the polyhydric alcohol
And at least two (meth) acryloyloxy groups
5 to 15 moles of polyfunctional (meth) acrylates
The urethane (meth) acrylate oligomer or urethane (meth) acrylate oligomer mixture obtained by using and reacting as an essential component can be copolymerized with the urethane (meth) acrylate oligomer or urethane (meth) acrylate oligomer mixture as necessary. A photocurable resin composition comprising one or more kinds of monomers. 9. An isocyanate having three or more isocyanate groups in a molecule is represented by the following formula: (Wherein, R represents the following Chemical Formula 9, Chemical Formula 11, Chemical Formula 11, or Chemical Formula 12)
A compound represented by an organic group represented by the formula: (Wherein, R represents the following Chemical Formula 9, Chemical Formula 11, Chemical Formula 11, or Chemical Formula 12)
The composition according to claim 8, which is at least one compound selected from compounds represented by the following formula: Embedded image Embedded image Embedded image Embedded image 10. A compound represented by Chemical Formula 7 is an isocyanurate of isophorone diisocyanate (a compound in which R is an organic group of Chemical Formula 9), or an isocyanurate of hexamethylene diisocyanate (R is a chemical compound of Chemical Formula 7). 10), an isocyanurate of tolylene diisocyanate (a compound in which R is an organic group of the formula (11)) and an isocyanurate of methylenebiscyclohexyl diisocyanate (the compound in which R is an organic compound of the formula (12)) 10. The composition according to claim 9, which is at least one member selected from the group consisting of: 11. A compound represented by the formula 8 is a biuret of isophorone diisocyanate (a compound in which R is an organic group of the formula 9) and a biuret of hexamethylene diisocyanate (a compound in which R is a compound of the formula 10). 10. The composition according to claim 9, which is at least one or more compounds selected from organic compounds. 12. A polyfunctional (meth) acrylate having at least one hydroxyl group and at least two (meth) acryloyloxy groups in the molecule is pentaerythritol tri (meth) acrylate or dipentaerythritol penta (meth) acrylate. At least one selected from trimethylolpropane di (meth) acrylate, ditrimethylolpropane tri (meth) acrylate and polypentaerythritol poly (meth) acrylate
A composition according to any of claims 8 to 11, which is at least one species. 13. The polyhydric alcohol having at least two hydroxyl groups in the molecule is at least one or more selected from trimethylolpropane, ditrimethylolpropane, glycerin, pentaerythritol, dipentaerythritol and polypentaerythritol. Item 13. The composition according to any one of Items 8 to 12. 14. The composition according to claim 8, further comprising a photopolymerization initiator.
14. The composition according to any one of claims to 13.