JP2003048927A - Energy ray-curable resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an energy-curable resin composition having no reduction in physical properties even in dilution in low viscosity. SOLUTION: This energy-curable resin composition comprises a urethane (meth)acrylate (I) obtained by reacting a polyisocyanate mixture (A) which is prepared by reacting an aliphatic polyisocyanate (a1) with a polyol (a2) in the presence of a uretedione-forming catalyst, has 0.1-1,300 mPa.s viscosity, 20-50% ratio of the number of nitrogen atoms of uretedione group to the total nitrogen atoms, <=20% ratio of the number of nitrogen atoms of isocyanurate group to the total nitrogen atoms, 0.1-40%; ratio of the number of nitrogen atoms of urethane group and allophanate group to the total nitrogen atoms and 67-100% ratio of the number of nitrogen atoms of allophanate group to the number of nitrogen atoms of urethane group and allophanate group with a (meth)acrylate compound (B) containing one hydroxy group.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention requires a urethane (meth) acrylate obtained by reacting a low-viscosity polyisocyanate mixture containing an allophanate group and a uretdione group with a (meth) acrylate compound having one hydroxyl group. The present invention relates to an energy ray-curable resin composition useful as a paint, ink, adhesive, etc. contained as a component.

[0002]

[Prior art]

In recent years, energy ray-curable resins which are cured by ultraviolet rays or electron beams have been highly evaluated for their low pollution and high-speed curing, and prevent damage to woodwork, paper, metal, vinyl chloride, and plastic molded products. Also, it has been put to practical use in surface coating for the purpose of preventing pollution and imparting design characteristics.

For example, as an energy ray curable resin,
In JP-A-2-32133, urethane acrylates obtained from isocyanurate and polyisocyanates having a uretdione structure are used, but all use polyisocyanates obtained from diisocyanate monomers. Since the isocyanurate type is composed of 3 molecules of an aliphatic diisocyanate monomer, the viscosity becomes high and a large amount of a low-functional compound must be used in order to obtain an appropriate coating viscosity.
Reduces solvent resistance and weather resistance. When trying to lower the viscosity, a uretdione structure composed of two molecules of an aliphatic diisocyanate monomer is formed, but such a low molecular weight type necessarily has an isocyanate group only at the molecular weight end, and thus necessarily has a low functional group number. However, there is a problem that the curability and wear resistance are deteriorated.

[0005]

The problem to be solved by the present invention is to provide an energy-curable resin composition having a low viscosity and having no deterioration in physical properties even when diluted.

[0006]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that a polyisocyanate (a) having a total of two or more isocyanate groups bonded to carbon atoms of an aliphatic hydrocarbon
A polyisocyanate mixture obtained by reacting 1) and a polyol (a2) as essential components in the presence of a uretdione-forming catalyst, the polyisocyanate mixture containing a uretdione group containing a large amount of allophanate groups, and one hydroxyl group. The energy ray-curable resin composition containing, as an essential component, a urethane (meth) acrylate obtained by reacting with a (meth) acrylate compound having a low viscosity and a fast curing property, and even when diluted with a diluent. The inventors have found that a cured product having excellent solvent resistance, weather resistance and the like can be obtained, and completed the present invention.

That is, according to the present invention, the polyisocyanate (a1) having a total of two or more isocyanate groups bonded to the carbon atoms of an aliphatic hydrocarbon and the polyol (a2) are essential components in the presence of a uretdione-forming catalyst. Which has a viscosity of 0.1 to 1300 mPa · s at 25 ° C. and a solid content of which is uretdione with respect to the total number of nitrogen atoms contained in the polyisocyanate mixture. The ratio of the number of nitrogen atoms forming the group is 20 to 50%, the ratio of the number of nitrogen atoms forming the isocyanurate group is 20% or less, and the total ratio of the number of nitrogen atoms forming the urethane group and the allophanate group is 0.1. Nitrogen constituting the allophanate group with respect to the total number of nitrogen atoms constituting the urethane group and the allophanate group at 40% Urethane (meth) acrylate (I) obtained by reacting a polyisocyanate mixture (A) having a proportion of the number of children of 67 to 100% with a (meth) acrylate compound (B) having one hydroxyl group is used as an essential component. The present invention provides an energy ray-curable resin composition containing the same.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The urethane (meth) acrylate (I) used in the present invention will be described. The urethane (meth) acrylate (I) is obtained by reacting the polyisocyanate mixture (A) with the (meth) acrylate compound (B) having one hydroxyl group, and the production method is not particularly limited. Examples include a method of reacting at a temperature of 20 to 140 ° C. Reaction temperature is 4
When the temperature is 0 to 80 ° C., the polymerization of the (meth) acryloyl group is unlikely to occur, which is preferable. Although the reaction can be carried out in a nitrogen atmosphere, it is preferable to carry out the reaction in a dry air atmosphere containing oxygen or a mixed atmosphere of oxygen and nitrogen because the acryloyl group is unlikely to cause polymerization.

When the urethane (meth) acrylate (I) is produced, the number of moles of hydroxyl groups (OH) contained in the (meth) acrylate compound (B) and the isocyanate group (A) contained in the polyisocyanate mixture (A). NCO) molar ratio (NCO / OH) is 95/100 to 1
It is preferably 00/95 because the storage stability is good and the amount of unreacted (meth) acrylate compound (B) remaining in the reaction system is small.

In the above reaction, an organic tin catalyst such as dibutyltin diacetate or dibutyltin dilaurate or a tertiary amine compound such as triethylamine may be used in order to accelerate the reaction.

Further, in order to suppress the polymerization of the acrylate group during the reaction, metquinone, hydroquinone,
A polymerization inhibitor such as 2,6-ditertiarybutyl-4-methylphenol (hereinafter abbreviated as BHT) may be used.

Next, the polyisocyanate mixture (A) used for the synthesis of the urethane (meth) acrylate (I)
Will be described. The polyisocyanate mixture (A) used in the present invention comprises a polyisocyanate (a1) having two or more isocyanate groups bonded to carbon of an aliphatic hydrocarbon in total and a polyol (a2) as essential components, and uretdione. A polyisocyanate mixture obtained by reacting in the presence of a cationization catalyst having a solid content of 2
The viscosity at 5 ° C. is 0.1 to 1300 mPa · s, and the ratio of the number of nitrogen atoms constituting the uretdione group to the total number of nitrogen atoms contained in the polyisocyanate mixture is 20 to 50%, and isocyanurate. The ratio of the number of nitrogen atoms constituting the group is 20% or less, and the total ratio of the number of nitrogen atoms constituting the urethane group and the allophanate group is 0.1 to 0.1%.
There is no particular limitation as long as the polyisocyanate mixture is 40% and the ratio of the number of nitrogen atoms forming the allophanate group to the total number of nitrogen atoms forming the urethane group and the allophanate group is 67 to 100%, but However, the solid content has a viscosity of 10 to 1000 mP at 25 ° C.
and the ratio of the number of nitrogen atoms forming the uretdione group to the total number of nitrogen atoms contained in the polyisocyanate mixture is 20 to 40%, and the ratio of the number of nitrogen atoms forming the isocyanurate group is a.s. 10% or less, the total ratio of the number of nitrogen atoms constituting the urethane group and the allophanate group is 1 to 30%, and the number of nitrogen atoms constituting the allophanate group with respect to the total number of nitrogen atoms constituting the urethane group and the allophanate group. The polyisocyanate mixture having a ratio of 85 to 100% is more preferable because an energy ray curable resin composition having a low viscosity and good curability and solvent resistance of the cured coating film can be obtained.

Even an aliphatic isocyanate group-containing polyisocyanate mixture obtained by reacting polyisocyanate (a1) and polyol (a2) as essential components in the presence of a uretdione-forming catalyst is included in the mixture. The ratio of the number of nitrogen atoms constituting the uretdione group to the total number of nitrogen atoms exceeds 50% is 150 ° C.
Stability at high temperatures exceeding 100 ° C will be significantly reduced and decomposed, and highly toxic isocyanate monomers will easily be generated.
The ratio of the number of nitrogen atoms constituting the isocyanurate group is 20.
% (Urethane (meth) acrylate (I)
Since the viscosity of the compound becomes high and it is necessary to add a large amount of a compound having a monofunctional active double bond in order to reduce the viscosity, the curability and the solvent resistance of the cured coating film remarkably decrease. Not preferable. In addition, when the ratio of the number of nitrogen atoms constituting the allophanate group to the total number of nitrogen atoms constituting the urethane group and allophanate group contained in the polyisocyanate mixture is less than 67%, many hydrogen bonds of the urethane group are present. If the viscosity becomes high and the content of isocyanate groups decreases, the amount of (meth) acryloyl groups in the urethane (meth) acrylate (I) decreases, which is not preferable.

The various polyisocyanates in the polyisocyanate mixture contain groups such as uretdione groups, isocyanurate groups, urethane groups, allophanate groups, biuret groups and isocyanate groups, which are starting materials. Since the structure is derived from the isocyanate group of the polyisocyanate (a1) and contains all nitrogen atoms, the ratio of each structure can be confirmed by quantifying the ratio of this nitrogen atom.

The method is 13 C-NMR measurement, and a peak peculiar to the isocyanate group is 122 ppm at 1 ppm.
Peak characteristic of isocyanurate group at 49 ppm, 157
Urethane-specific peaks at ppm, 154 ppm and 156
Peak peculiar to allophanate group at ppm, 158 ppm
Since a peak peculiar to the uretdione group can be observed, the area of each peak is integrated, and the ratio of nitrogen atoms in the polyisocyanate mixture is calculated from the integration ratio.

The viscosity can be measured with a B type viscometer.

A polyisocyanate (a) having a total of two or more isocyanate groups bonded to carbon of an aliphatic hydrocarbon, which is used for preparing the polyisocyanate mixture (A).
1) and the polyol (a2) will be described. In the present invention, the isocyanate group bonded to the carbon of the aliphatic hydrocarbon also includes the isocyanate group bonded to the carbon of the alicyclic ring of the alicyclic hydrocarbon. Further, the polyisocyanate (a1) having a total of two or more isocyanate groups bonded to the carbon of the aliphatic hydrocarbon may be one having an isocyanate group bonded to the carbon of the aliphatic hydrocarbon, for example, xylylene diisocyanate. Such as those including an aromatic ring structure in the structure.

Examples of the polyisocyanate (a1) include tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate (hereinafter abbreviated as HDI), heptamethylene diisocyanate, octamethylene diisocyanate, decamethylene diisocyanate, 2-methyl-isocyanate. 1,5-pentane diisocyanate, 3-methyl-1,5-pentane diisocyanate, xylylene diisocyanate, tetramethyl xylylene diisocyanate, dodecamethylene diisocyanate, 2-methylpentamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-Trimethylhexamethylene diisocyanate, isophorone diisocyanate, norbornane diisocyanate , Hydrogenated diphenylmethane diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated xylylene diisocyanate, hydrogenated tetramethyl xylylene diisocyanate, cycloaliphatic diisocyanate and other alicyclic diisocyanates, polymethylene polyphenylene polyisocyanate and other polymeric type polyisocyanates, etc. Can be mentioned.

These organic isocyanates can be used alone or as a mixture of two or more kinds.

The polyisocyanate (a1) is preferably a diisocyanate having an aliphatic or alicyclic hydrocarbon bonded to an isocyanate group and having 4 to 15 carbon atoms, and more preferably hexamethylene diisocyanate.

Next, the polyol (a2) will be described. Examples of the polyol (a2) include alkylene polyols, polyester polyols, polycarbonate polyols, polyether polyols, polyolefin polyols, animal and plant polyols, and copolyols thereof.

As the alkylene polyol, for example,
Ethylene glycol, 1,2-propylene glycol (hereinafter abbreviated as 1,2-PG), 1,3-propylene glycol, 1,2-butanediol (hereinafter, 1,2)
-Abbreviated as BD. ), 1,3-butanediol (hereinafter,
It is abbreviated as 1,3-BD. ), 1,4-butanediol,
1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol (hereinafter referred to as M
Abbreviated as PD. ), Neopentyl glycol (hereinafter, N
Abbreviated as PG. ), 3,3-dimethylolheptane (hereinafter abbreviated as DMH), 1,8-octanediol,
1,9-nonanediol, 1,10-decanediol,
1,12-dodecanediol, 1,18-octadecanediol, 2-hydroxystearyl alcohol, 12
-Hydroxystearyl alcohol, 1,4-cyclohexanedimethanol, glycerin, trimethylolpropane, pentaerythritol, 1,2,2-trimethyl-1,3-propanediol, 2,2-dimethyl-3-
Isopropyl-1,3-propanediol, 2,2-dimethyl-3-benzyl-1,3-propanediol,
2,2-dimethyl-3-isobutyl-1,3-propanediol, 2,2,3,3-tetramethyl-1,4-butanediol, 2,2,4-trimethyl-1,5-pentanediol ( Hereinafter, abbreviated as TMPD), 2, 2,
4-Trimethyl-1,6-hexanediol, 2-hydroxypalmityl alcohol, 2,2-bis (4-hydroxycyclohexyl) propane (commonly known as hydrogenated bisphenol A) and the like can be mentioned.

Examples of polyester polyols include oxalic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, terephthalic acid, isophthalic acid, orthophthalic acid, hexahydroterephthalic acid, hexahydroisophthalic acid, hexahydroorthophthalic acid, One or more of polycarboxylic acids such as naphthalenedicarboxylic acid, trimellitic acid, pyromellitic acid, (partial) acid ester, or (partial) acid anhydride, and ethylene glycol, 1,2-PG,
1,3-propylene glycol, 1,2-BD, 1,3
-BD, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, MPD, NPG,
DMH, 1,8-octanediol, 1,9-nonanediol, diethylene glycol, DPG, 1,4-cyclohexanedimethanol, ethylene oxide adduct of bisphenol A, propylene oxide adduct of bisphenol A, glycerin, trimethylolpropane,
Examples thereof include polyester polyols obtained by a dehydration condensation reaction with a low molecular weight polyol such as pentaerythritol and a low molecular weight amino alcohol such as monoethanolamine and diethanolamine. Further, a lactone polyester polyol obtained by ring-opening polymerization of a cyclic ester (lactone) monomer such as ε-caprolactone or γ-valerolactone using the low molecular weight polyol as an initiator.

Examples of the polycarbonate polyol include those obtained by reacting the low molecular weight polyol used in the above polyester polyol with ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, diphenyl carbonate and the like.

As the polyether polyol, for example, diethylene glycol, triethylene glycol,
Polyalkylene glycols such as dipropylene glycol and tripropylene glycol; poly (oxyalkylene) polyols obtained by ring-opening polymerization of a single product or a mixture of cyclic ethers such as ethylene oxide, propylene oxide and tetrahydrofuran, and the above-mentioned polyester polyols and polycarbonate polyols. As the initiator, a polyester ether polyol obtained by polymerizing the cyclic ether can be mentioned.

Examples of the polyolefin polyol include hydroxyl group-containing polybutadiene, hydrogenated hydroxyl group-containing polybutadiene, hydroxyl group-containing polyisoprene, hydrogenated hydroxyl group-containing polyisoprene, hydroxyl group-containing chlorinated polypropylene, hydroxyl group-containing chlorinated polyethylene and the like.

Examples of animal and plant polyols include castor oil-based polyols and silk fibroin.

Further, if it has two or more active hydrogen groups, dimer acid type polyol, hydrogenated dimer acid type polyol, epoxy resin, polyamide resin, polyester resin, acrylic resin, rosin resin, urea resin, melamine resin. Resins such as phenol resin, coumarone resin and polyvinyl alcohol can also be preferably used as the polyol (a2).

Among these polyols (a2), low molecular weight alcohols having 2 to 40 carbon atoms are preferable because the isocyanate group content of the polyisocyanate mixture is high, and polyols having 3 to 10 carbon atoms are particularly preferable. Specifically, 1,2-PG, 1,2-BD, 1,
3-BD, MPD, NPG, DMH, DPG, TMP
Particularly preferred are diols having 3 to 10 carbon atoms, such as D and CHDM.

In the present invention, a monofunctional compound may be used in combination in order to adjust the average number of isocyanate groups, compatibility, reactivity and the like. Examples of the monofunctional compound include low molecular weight monoalcohols such as methanol, ethanol, propanol, 2-ethyl-hexanol and benzyl alcohol, high molecular weight monools such as methoxypoly (oxyethylene) glycol and ricinoleic acid alkyl ester, and diethylamine. , Monoamines such as dibutylamine, butyl isocyanate, cyclohexyl isocyanate, octadecyl isocyanate, paratoluene sulfonyl isocyanate, and monoisocyanates such as 2-methacryloyloxyethyl isocyanate. These may be used alone or in combination of two or more. The reaction time of this monofunctional compound is not particularly limited,
It may be appropriately selected depending on the viscosity and the degree of modification.

Next, a method for producing the polyisocyanate mixture (A) will be described. As the method for producing the polyisocyanate mixture (A), polyisocyanate (a
A method of reacting 1) and a polyol (a2) as essential components in the presence of a uretdione-forming catalyst, wherein the solid content of the resulting polyisocyanate mixture at 25 ° C. is 0.1 to 1300 mPa · s. And the ratio of the number of nitrogen atoms constituting the uretdione group to the total number of nitrogen atoms contained in the polyisocyanate mixture is 2
0 to 50%, the ratio of the number of nitrogen atoms constituting the isocyanurate group is 20% or less, the total ratio of the number of nitrogen atoms constituting the urethane group and the allophanate group is 0.1 to 40%,
A method for obtaining a polyisocyanate mixture in which the ratio of the number of nitrogen atoms constituting the allophanate group to the total number of nitrogen atoms constituting the urethane group and the allophanate group is 67 to 100%, for example, polyisocyanate (a1) and polyol (A2) is a molar ratio of isocyanate group (NCO) and hydroxyl group (OH) (NCO / OH)
Is 4/1 to 100/1, preferably 10/1 to 50/1
In the range to be charged, urethanization and subsequent allophanate formation are carried out, then uretdione formation is started in the presence of a uretdione formation catalyst, and after the uretdione formation reaction is stopped, a method of removing unreacted polyisocyanate (a1), The polyisocyanate (a1) is uretdione-ized in the presence of a uretdione-forming catalyst, and after the uretdione-forming reaction is stopped, the polyol (a2) is added to carry out urethanization and subsequent allophanate formation, and then the unreacted polyisocyanate (a1) ), The uretdione formation is initiated in the presence of a uretdione formation catalyst at the same time as or during the urethane formation and the subsequent allophanate formation, and after the uretdione formation reaction is stopped, the unreacted polyisocyanate (a1) is removed. , Etc., among them, the reaction time is short and efficient. From, the method is preferred with.

The reaction between the polyisocyanate (a1) and the polyol (a2) is not to stop the reaction by urethanization for the purpose of lowering the viscosity and polyfunctionalizing the polyisocyanate (a1) to form an allophanate. Since it is necessary to increase the ratio, a temperature of 80 to 150 ° C., which is higher than the usual urethanization conditions, is preferable. More preferably,
90 to 140 ° C. The reaction time for urethanization and subsequent allophanate formation varies depending on the reaction temperature and is not particularly limited, but is usually 1 minute to 24 hours, and is preferably 10 minutes to 12 hours because the reaction is easy to control and the efficiency is good.

As the catalyst for obtaining the polyisocyanate mixture, various uretdione-forming catalysts are used. Specifically, antimony pentafluoride, triethylphosphine,
Dibutylethylphosphine, tri-n-propylphosphine, triisopropylphosphine, tri-n-butylphosphine, triisobutylphosphine, tritertiarybutylphosphine, triamylphosphine, trioctylphosphine, tribenzylphosphine, benzylmethylphosphine, amino Substituted phosphine, imidazole, guanidine and pyridine, boron trifluoride, 1,2-dimethylimidazole, tris- (N, H-dimethylamino)
-Phosphine, tris- (N, N-diethylamino) phosphine, cyclic amidine, 1,8-diazabicyclo- [5,4,0] undecay-7-ene, 4-aminopyridine, 4-dialkylaminopyridine and the like can be mentioned. Among these, triethylphosphine, dibutylethylphosphine, tri-n-propylphosphine, triisopropylphosphine, tri-n-butylphosphine, triisobutylphosphine, tritertiary butylphosphine, triamylphosphine, trioctylphosphine, etc. Trialkylphosphine is preferred.

The reaction temperature for uretdione formation is usually 40 to
The temperature is 140 ° C, preferably 60 to 120 ° C. When the urethanization, the subsequent allophanate formation, and the uretdione formation are carried out simultaneously, the reaction temperature is usually 8
It is in the range of 0 to 140 ° C, preferably 90 to 120 ° C. The reaction time for uretdione formation varies depending on the reaction temperature and is not particularly limited, but is usually 10 minutes to 24 hours, and the reaction time is easy to control and is efficient, so 30 minutes to
12 hours is preferred.

Usually, these reactions can be carried out without a solvent, but if necessary, an inert solvent which is commonly used in the polyurethane industry, such as toluene, xylene or swazol (an aromatic hydrocarbon solvent manufactured by Cosmo Oil Co., Ltd.) is used. ), An aromatic solvent such as Solvesso (an aromatic hydrocarbon solvent manufactured by Exxon Chemical Co., Ltd.), a ketone solvent such as methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone,
Ester solvents such as ethyl acetate, butyl acetate, isobutyl acetate, ethylene glycol ethyl ether acetate, propylene glycol methyl ether acetate,
3-methyl-3-methoxybutyl acetate, ethyl-
Since one or more glycol ether ester type solvents such as 3-ethoxypropionate and ether type solvents such as tetrahydrofuran and dioxane can be used, the viscosity can be adjusted according to the reaction conditions.

After the uretdione-forming reaction, a reaction-terminating agent for the uretdione-forming reaction is added to stop the reaction.

Examples of the uretdione-formation reaction terminator include hydrogen chloride, nitric acid, sulfuric acid, phosphoric acid, acetic acid, monochloroacetic acid, benzoic acid, phthalic acid, benzenesulfonic acid, toluenesulfonic acid, methyl paratoluenesulfonate, and naphthalene. Sulfonic acid, aluminum trichloride, boron trifluoride, boron trichloride, iron trifluoride, iron trichloride, trichlorosilane, diphenyltrichlorosilane, diphenyldichlorosilane, dimethyl sulfate, benzoyl peroxide, perfluorobutanesulfonic acid, sulfur , Sulfonyl isocyanate, silylated acid, organic (hydro) peroxide, peroxycarboxylic acid, oxygen, and a mixture thereof, and the like, but phosphoric acid, benzenesulfonic acid, toluenesulfonic acid, naphthalenesulfone are preferable. Acid, p-toluenesulfonic acid methyl ester , Dimethyl sulfate, benzoyl peroxide, perfluorobutane sulfonic acid, oxygen, and mixtures thereof, among others phosphoric acid, methyl p-toluenesulfonate are preferred.

The free unreacted isocyanate monomer present in the terminated polyisocyanate mixture is extracted, for example, with n-hexane or 0.0
Residual contents of at most 1% by weight are removed by suitable means such as thin film distillation at 120-140 ° C. under high vacuum of 1-1 Torr. The recovered diisocyanate monomer and organic solvent can be reused and effectively utilized after separation and purification.

Next, the (meth) acrylate compound (B) having one hydroxyl group used in the present invention will be explained. Examples of the (meth) acrylate compound (B) include hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, pentanediol mono (meth).
Mono (meth) acrylate of dihydric alcohol such as acrylate, hexanediol mono (meth) acrylate, neopentyl glycol mono (meth) acrylate, and hydroxypivalic acid neopentyl glycol mono (meth) acrylate;

Mono- or di-valent trihydric alcohols such as trimethylolpropane di (meth) acrylate, ethoxylated trimethylolpropane (meth) acrylate, propoxylated trimethylolpropane di (meth) acrylate, glycerin di (meth) acrylate, etc. (Meth) acrylates having one hydroxyl group, and mono- and di (meth) acrylates having one hydroxyl group obtained by modifying a part of the hydroxyl groups of these alcohols with an alkyl group or ε-caprolactone;

Pentaerythritol tri (meth) acrylate, ditrimethylolpropane tri (meth) acrylate, dipentaerythritol pentaacrylate, and other polyfunctional (meth) acrylates of tetravalent or more alcohols having one hydroxyl group, and Examples thereof include polyfunctional (meth) acrylates having a hydroxyl group obtained by modifying a part of the hydroxyl group of alcohol with an alkyl group or ε-caprolactone.

The (meth) acrylate compound (B) includes hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate and hydroxybutyl (meth).
A (meth) acrylate compound having a molecular weight of 100 to 150 or less per (meth) acryloyl group, such as acrylate and pentaerythritol tri (meth) acrylate, is preferable because of good curability, and hydroxyethyl acrylate and hydroxypropyl acrylate. Is particularly preferable.

The energy ray-curable resin composition of the present invention comprises a urethane (meth) acrylate (I) obtained by reacting a polyisocyanate mixture (A) with a (meth) acrylate compound (B) having one hydroxyl group. As long as it is contained, the (meth) acrylate monomer (II) can be added as a diluting monomer in order to adjust the coating viscosity to an appropriate level.

Examples of the (meth) acrylate monomer (II) include 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, isobornyl (meth) acrylate, dipropylene glycol (meth) acrylate and ethoxy. Diethylene glycol (meth) acrylate, hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, dicyclopentenyl (meth)
Acrylate,

Neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, dimethylol tricyclodecane di (meth) acrylate, hydroxypivalin Acid neopentyl glycol di (meth) acrylate, neopentyl glycol modified trimethylolpropane di (meth) acrylate, tripropylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, bis ( (Meta)
Acryloxyethyl) bisphenol A,

Trimethylolpropane tri (meth) acrylate, ethylene oxide modified trimethylolpropane ditri (meth) acrylate, propylene oxide modified trimethylolpropane tri (meth) acrylate, glycerin tri (meth) acrylate, ethylene oxide modified glycerin tri (meth) ) Acrylate, propylene oxide-modified glycerin tri (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate,

Pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate, and a part of these (meth) acrylates as an alkyl group or ε. Examples thereof include polyfunctional (meth) acrylates substituted with caprolactone.

Other acryloylmorpholine having an active double bond, triethylene glycol divinyl ether,
Hydroxyethyldivinyl ether, styrene, divinylbenzene and the like can also be used as the diluting monomer.

The (meth) acrylate monomer (II) is
Since the hydrogen bond due to the urethane bond of the urethane (meth) acrylate (I) is cut, the viscosity is reduced with a small amount of the compound, and the curability and the solvent resistance of the cured coating are less likely to decrease. Hydroxyl group-containing (meth) acrylates such as (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and pentaerythritol triacrylate are preferable.

Further, the (meth) acrylate monomer (I
The amount of (I) used is urethane (meth) acrylate (I) because the solvent resistance and abrasion resistance of the cured coating do not decrease.
And (meth) acrylate monomer (II) weight ratio (I)
/ (II) should be 90/10 to 20/80, 70
/ 30 to 30/70 is more preferable.

In the energy ray-curable resin composition of the present invention, an organic solvent (C), a photopolymerization initiator (D), a matting agent (E), a pigment (F), a natural or synthetic polymer can be used depending on the purpose. Molecular substances (G) and other compounding agents (H) may be additionally used.

The energy ray-curable resin composition of the present invention may contain an organic solvent for viscosity adjustment depending on the use. When an organic solvent is used, it is preferable to remove the organic solvent with a hot air dryer after coating. Therefore, it is preferable that the amount of the organic solvent used is small. Organic solvent (C)
Examples of the ester include esters such as ethyl acetate and butyl acetate; ketones such as methyl ethyl ketone and methyl isobutyl ketone; ethylene glycol monoethyl ether,
Examples thereof include ethers such as propylene glycol monomethyl ether; aromatic hydrocarbons such as toluene and xylene; alcohols such as methanol and isopropyl alcohol; and mixtures thereof. When an organic solvent is used, it is preferable to remove the organic solvent with a hot air dryer after coating, and therefore, it is preferable that the amount of the organic solvent used is small.

As the photopolymerization initiator (D), various ones can be used without limitation. For example, a compound such as benzophenone, benzyl, Michler's ketone, thioxanthone or anthraquinone, which generates a radical by hydrogen abstraction, etc. Is mentioned. These compounds are generally used in combination with tertiary amines such as methylamine, diethanolamine, N-methyldiethanolamine and tributylamine. As another type, for example, a compound of a type that generates a radical by intramolecular splitting, such as benzoin, dialkoxyacetophenone, acyloxime ester, benzyl ketal, hydroxyalkylphenone, acylphosphine oxide, aminoketone and halogenoketone. Can be mentioned.

If necessary, hydroquinone, metoquinone, benzoquinone, 2,6-tert-butyl-
Polymerization inhibitors such as 4-methylphenol can also be added.

Examples of the matting agent (E) include calcium carbonate, talc, mica, clay, silica powder,
Colloidal silica, aluminum hydroxide, zinc stearate, etc. may be mentioned.

Examples of the pigment (F) include pigments such as zinc white, titanium white, red iron oxide, and azo pigment.

Examples of natural or synthetic polymeric substances (G) include various vinyl ester resins, polyisocyanate compounds, polyepoxides, acrylic resins, alkyd resins, urea resins, melamine resins, poly Vinyl acetate, vinyl acetate copolymers, polybutadiene elastomer, saturated polyesters, saturated polyethers, cellulose derivatives such as nitrocellulose or cellulose acetate butyrate, linseed oil, tung oil, soybean oil, castor oil or epoxy Fats and oils such as fossil oils may be mentioned.

Other compounding agents (H) include antioxidants, ultraviolet absorbers, leveling agents, surfactants, slip agents, defoaming agents and the like.

The energy ray-curable resin composition of the present invention is adjusted to an appropriate coating viscosity and applied to a base material, and ultraviolet rays, visible light, laser light, electron rays, X rays, γ rays, plasma, microwaves are used. It is possible to form a coating film, an adhesive layer, and an ink layer by curing by irradiating an energy ray such as.

[0060]

EXAMPLES The present invention will be described below with reference to examples and comparative examples. Unless otherwise specified, “parts” and “%” in the examples mean “parts by weight” and “% by weight”, respectively. Means

In this example, the viscosity of the polyisocyanate mixture was measured using a B type viscometer. Further, the ratio of the total number of nitrogen atoms constituting the isocyanate group, the uretdione group, the isocyanurate group, the urethane group, and the allophanate group to all the nitrogen atoms contained in the polyisocyanate mixture is 122 p by the ¹³ C-NMR measurement.
The peak peculiar to the isocyanate group of pm, the peak peculiar to the isocyanurate group of 149 ppm, the peak peculiar to the urethane of 157 ppm, the peak peculiar to the allophanate group of 154 ppm and 156 ppm, the peak peculiar to the uretdione group of 158 ppm, and the respective peak areas are shown. After integration, the ratio of nitrogen atoms in the polyisocyanate mixture was calculated from the integration ratio.

The viscosity of the energy ray-curable resin composition is
The viscosity at 25 ° C. was measured by the Gardner-type foam viscometer method.

Synthesis Example 1 [Polyisocyanate mixture (A
Synthesis of -1)] A reactor equipped with a stirrer, a thermometer, an Arene cooling pipe, and a nitrogen gas introduction pipe was charged with 293.0 parts of HDI and 7.0 parts of 1,3-butanediol, and the inside of the reactor was filled with nitrogen. After substituting, the temperature was raised to 140 ° C. with stirring, urethanization and allophanate formation were carried out at the same temperature for 8 hours, and then 0.15 parts of tributylphosphine was charged and reacted for uretdione formation. After that, 0.15 parts of methyl paratoluenesulfonate, which is a catalyst poison, was charged to terminate the uretdione-forming reaction, and the liquid temperature was gradually cooled to room temperature. After cooling, the NCO% (weight content of isocyanate groups contained in 1 g of the sample) was 38.0%. Then, using a thin film distillation apparatus, distilled at 130 ° C. and 0.5 Torr,
The free isocyanate monomer was removed to obtain a polyisocyanate mixture (A-1). (A-1) NCO
% Is 21.0% and the viscosity at 25 ° C. is 200 m
Pa · s, free isocyanate monomer content is 1%
The ratio of the number of nitrogen atoms constituting the uretdione group, isocyanurate group, urethane group, allophanate group, and isocyanate group to all nitrogen atoms is 35%, 10%, 1%, 12%, and 42%, respectively. The ratio of the number of nitrogen atoms forming the allophanate group to the total number of nitrogen atoms forming the urethane group and the allophanate group was 92%.

Synthesis Example 2 [Synthesis of Polyisocyanate Mixture (a-2) for Comparative Control] 300.0 parts of HDI was charged into a reactor equipped with a stirrer, a thermometer, an arene cooling pipe, and a nitrogen gas introducing pipe, and the reactor was charged. The inside was replaced with nitrogen, the temperature was raised to 80 ° C. with stirring, and N, N, N-trimethyl-as an isocyanurate-forming catalyst was used.
One part of a 20% solution of N-2-hydroxypropylammonium para-tertiary butyl benzoate was charged, and an isocyanurate-forming reaction was carried out at the same temperature for 6 hours. Thereafter, 0.1 part of 7% monochloroacetic acid, which is a catalyst poison, was charged to terminate the reaction, and the solution was gradually cooled to room temperature. The NCO% after cooling was 44%. Then, using a thin-film distillation apparatus, it distilled at 130 degreeC and 0.5 Torr, the free isocyanate monomer was removed, and the polyisocyanate mixture (a-2) for comparison and control was obtained. (A-2) has an NCO% of 20% and a viscosity at 25 ° C. of 1600 mP.
a · s, free isocyanate monomer content is 1%
The ratios of the numbers of nitrogen atoms constituting the isocyanurate group and the isocyanate group were 53 and 47%, respectively.

Synthesis Example 3 [Urethane acrylate (I-
Synthesis of 1)] The polyisocyanate mixture (A-1) 3 was added to a reactor equipped with a stirrer, a thermometer, an Arene cooling pipe, and a dry air introduction pipe.
01 parts, BHT 1.5 parts, methquinone 0.15 parts, and dibutyltin diacetate 0.05 parts as a catalyst were charged, and the temperature was raised to 80 ° C. with stirring. -200 parts of hydroxypropyl acrylate was charged separately and urethane reaction was carried out at the same temperature for about 8 hours until NCO% became 0.1% or less to obtain urethane acrylate (I-1).

Synthesis Example 4 [Urethane acrylate (I-
Synthesis of 2)] The polyisocyanate mixture (A-1) 3 was added to a reaction device equipped with a stirrer, a thermometer, an Arene cooling pipe, and a dry air introduction pipe.
14 parts, BHT 1.5 parts, methoquinone 0.15 parts, and dibutyltin diacetate 0.05 parts as a catalyst were charged, and the temperature was raised to 80 ° C. with stirring. Ethyl acrylate 18
Six parts were charged separately and urethane reaction was carried out at the same temperature for about 8 hours until the NCO% became 0.1% or less to obtain urethane acrylate (I-2).

Synthesis Example 5 [Synthesis of Comparative Urethane Acrylate (i-3)] A polyisocyanate mixture (a-2) 3 was placed in a reactor equipped with a stirrer, a thermometer, an Arene cooling pipe, and a dry air introducing pipe.
03.4 parts, BHT 1.5 parts, methquinone 0.15 parts,
Dibutyltin diacetate (0.05 parts) was charged as a catalyst, the temperature was raised to 80 ° C. with stirring, and 196.6 parts of hydroxyethyl acrylate was charged in portions while cooling with care to prevent heat generation and NCO% was 0. The urethane reaction was carried out at the same temperature for about 8 hours until the content became 0.1% or less to obtain a urethane acrylate (i-3) for comparison.

Synthesis Example 6 [Synthesis of Comparative Control Urethane Acrylate (i-4)] HDI 196.2 parts, BHT 1.5 parts in a reactor equipped with a stirrer, a thermometer, an arene cooling tube and a dry air introducing tube,
0.15 parts of methoquinone and 0.05 parts of dibutyltin diacetate as a catalyst were charged, the temperature was raised to 80 ° C. with stirring, and 303.7 parts of 2-hydroxypropyl acrylate was cooled while paying attention to heat generation and cooling if necessary. Was dividedly charged, and urethane reaction was carried out at the same temperature for about 8 hours until the NCO% became 0.1% or less to obtain urethane acrylate (i-4) as a comparative control.

Example 1 60 parts of urethane acrylate (I-1), 40 parts of ethylene oxide-modified trimethylolpropane triacrylate [TMP (EO) TA], and 3 parts of Irgacure 184 as a photoinitiator were mixed, and Gardner foam was prepared. Viscometer method (2
An energy ray-curable resin composition having a viscosity at 5 ° C. of XY was obtained. The evaluation results are shown in Table 1 together with the constituent components. The following items were evaluated.

Evaluation item 1; Evaluation of curability The energy ray-curable resin composition was applied to a polycarbonate plate so as to have a dry film thickness of 50 μm, and passed through a high pressure mercury lamp of 80 W / cm at a speed of 10 m / min. The curability of the coating film formed each time it was passed was evaluated by touch with a finger. The number of passages until the coating was not sticky and the curing was good was evaluated.

Evaluation item 2: Evaluation of solvent resistance An energy ray-curable resin composition was applied on a polycarbonate plate so that a dry film thickness was 50 μm, and was exposed under a high pressure mercury lamp of 80 W / cm 5 times at a speed of 10 m / min. It was allowed to pass and a cured coating film was obtained. Using this cured coating, M under a load of 500 g
An EK rubbing test was conducted, and those having a good appearance were evaluated as ◯, and those in which the coating film was whitened or the substrate was visible were evaluated as x.

Evaluation item 3: Evaluation of abrasion resistance After obtaining a cured coating film in the same manner as in evaluation item 2, the evaluation was carried out using a Taber abrasion tester and a CS17 Taber type abrasion wheel. The case where the coating film was scraped and slightly whitened was evaluated as Δ, and the case where the coating film was considerably whitened and the appearance was poor was evaluated as x.

Example 2 60 parts of urethane acrylate (I-1), 40 parts of isobornyl acrylate (IBXA), and 3 parts of Irgacure 184 which is a photoinitiator were blended, and a Gardner-type foam viscometer method (25 ° C.) was used. An energy curable resin composition having a viscosity of TU was obtained. The results of evaluation performed in the same manner as in Example 1 are shown in Table 1.

Example 3 60 parts of urethane acrylate (I-1), 40 parts of hydroxyethyl acrylate (HEA), and 3 parts of Irgacure 184 as a photoinitiator were mixed, and the viscosity (25 An energy ray-curable resin composition having a temperature of (C) of GH ² was obtained. The results of evaluation performed in the same manner as in Example 1 are shown in Table 1.

Example 4 60 parts of urethane acrylate (I-2), 40 parts of hydroxyethyl acrylate (HEA) and 3 parts of Irgacure 184 as a photoinitiator were mixed, and the viscosity (25 An energy ray-curable resin composition having a temperature of (C) of GH ² was obtained. The results of evaluation performed in the same manner as in Example 1 are shown in Table 1.

Example 5 60 parts of urethane acrylate (I-2), 40 parts of ethylene oxide-modified trimethylolpropane triacrylate [TMP (EO) TA], and 3 parts of Irgacure 184 as a photoinitiator were mixed, and Gardner was added. An energy ray curable resin composition having a viscosity (25 ° C.) of Y by a foam froth viscometer method was obtained. The results of evaluation performed in the same manner as in Example 1 are shown in Table 1.

Comparative Example 1 60 parts of urethane acrylate (i-3), 40 parts of ethylene oxide-modified trimethylolpropane triacrylate [TMP (EO) TA], and 3 parts of Irgacure 184 as a photoinitiator were mixed, and Gardner-type foam was prepared. An energy ray-curable resin composition having a viscosity (25 ° C.) according to a viscometer method of Z ₁ -Z ₂ ² was obtained. The results of evaluation performed in the same manner as in Example 1 are shown in Table 2.

Comparative Example 2 When 60 parts of urethane acrylate (i-4), 40 parts of ethylene oxide-modified trimethylolpropane triacrylate [TMP (EO) TA] and 3 parts of Irgacure 184 as a photoinitiator were mixed, 25 ° C. Crystallization was observed at. In Comparative Example 2, the evaluation shown in Example 1 was impossible because of the crystallization of the resin composition.

[0079]

[Table 1]

[0080]

[Table 2]

[0081]

The energy ray-curable resin composition of the present invention has low viscosity and fast curability. Further, the energy ray-curable resin composition of the present invention can provide a cured product having excellent solvent resistance and abrasion resistance. Therefore, it is useful for paints, adhesives, printing inks, etc., and is most suitable for paints.

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 4J027 AA01 AG02 AG03 AG04 AG09                       AG10 AG12 AG13 AG14 AG15                       AG23 AG24 AG27 AG28                 4J034 CA03 CA04 CB01 CB02 CB03                       CB04 CC03 CC37 CC38 DB01                       DB03 DB04 DC01 DC02 DC03                       DC50 DF01 DF02 DG02 DG03                       DG04 HC01 HC03 HC12 HC18                       HC61 HC63 HC71 KA01 RA07                       RA08

Claims (8)

[Claims] 1. A polyisocyanate (a1) having a total of two or more isocyanate groups bonded to carbon atoms of an aliphatic hydrocarbon and a polyol (a2) as essential components,
A polyisocyanate mixture obtained by reacting in the presence of a uretdione-forming catalyst, the solid content of which has a viscosity at 25 ° C. of 0.1 to 1300 mPa · s, and
The ratio of the number of nitrogen atoms forming the uretdione group to the total number of nitrogen atoms contained in the polyisocyanate mixture is 20 to 50%, the ratio of the number of nitrogen atoms forming the isocyanurate group is 20% or less, and the urethane group and allophanate. The total ratio of the number of nitrogen atoms constituting the group is 0.1 to 40%
And a polyisocyanate mixture (A) in which the ratio of the number of nitrogen atoms constituting the allophanate group to the total number of nitrogen atoms constituting the urethane group and allophanate group is 67 to 100%, and one hydroxyl group (meta) ) An energy ray-curable resin composition, comprising a urethane (meth) acrylate (I) obtained by reacting with an acrylate compound (B) as an essential component. 2. A polyisocyanate (a1), wherein the aliphatic hydrocarbon bonded to the isocyanate group has 4 carbon atoms.
The energy ray-curable resin composition according to claim 1, which is an aliphatic diisocyanate of -15. 3. The polyol (a2) has from 2 to 2 carbon atoms.
The energy ray-curable resin composition according to claim 1 or 2, which is 40 polyhydric alcohol. 4. The (meth) acrylate compound (B) having one hydroxyl group is a (meth) acrylate compound having a molecular weight of 100 to 150 per one (meth) acryloyl group. The energy ray-curable resin composition described. 5. A urethane (meth) acrylate (I) and a (meth) acrylate monomer (II) are contained in a weight ratio (I) / (II) of 90/10 to 20/80. The energy ray-curable resin composition according to any one of claims 1 to 4. 6. A (meth) acrylate monomer (II)
Is a hydroxyl group-containing (meth) acrylate, and the energy ray-curable resin composition according to any one of claims 1 to 5. 7. The viscosity of the resin component of the polyisocyanate mixture at 25 ° C. is 10 to 1000 mPa · s, and the number of nitrogen atoms constituting the uretdione group is based on the total number of nitrogen atoms contained in the polyisocyanate mixture. Is 20 to 40%, the ratio of the number of nitrogen atoms constituting the isocyanurate group is 10% or less, and the ratio of the total number of nitrogen atoms constituting the urethane group and the allophanate group is 1 to 30.
%, And the ratio of the number of nitrogen atoms constituting the allophanate group to the total number of nitrogen atoms constituting the urethane group and the allophanate group is 85 to 100%.
The energy ray-curable resin composition according to any one of 6 above. 8. The polyisocyanate mixture (A) comprises a polyisocyanate (a1) and a polyol (a2).
80-150 when the molar ratio (NCO / OH) of isocyanate group to hydroxyl group is 4/1 to 100/1.
Perform urethanation and subsequent allophanate formation at ℃,
After that, uretdione formation is started in the presence of a uretdione formation catalyst at 40 to 140 ° C., and after the uretdione formation reaction is stopped, the unreacted polyisocyanate (a1) is removed.
Alternatively, at 80 to 140 ° C., uretdione formation is started in the presence of a uretdione formation catalyst at the same time as or during urethanization and subsequent allophanate formation, and after the uretdione formation reaction is stopped, unreacted polyisocyanate (a1) Obtained by a method excluding
7. The energy ray curable resin composition according to any one of 7.