JP2001019729A - Resin composition and its cured material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a resin composition having high stability, giving a cured product having faint color and good adhesivity and useful as a printing ink for screen printing, offset printing, gravure printing, intaglio printing, etc., by including a (meth)acrylic acid ester and an oligomer. SOLUTION: The objective composition contains (A) a (meth)acrylic acid ester of formula (R is H or methyl) (e.g. 2,3-carbonatopropyl acrylate) and (B) an oligomer [e.g. an epoxy (meth)acrylate]. The amounts of the components A and B are preferably 2-60 wt.% and 40-98 wt.% based on 100 wt.% of A+B, respectively. The composition may be further incorporated with preferably 0.1-15 wt.% photopolymerization initiator e.g. 2-methyl-1-[4-(methylthio) phenyl]-2-morpholino-propan-1-one}.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a resin composition and a cured product thereof. More specifically, the present invention relates to a resin composition suitable for a printing ink such as a screen printing ink, an offset printing ink, a gravure printing ink, an intaglio printing ink, and a cured product thereof.

[0002]

BACKGROUND OF THE INVENTION Radiation-curable acrylic oligomers often have high viscosities and must be mixed with monomers to produce a composition of suitable viscosity for a particular application. Representative examples of such oligomers include epoxy (meth) acrylate, urethane (meth) acrylate and polyester (meth) acrylate. For example, Japanese Patent Application Laid-Open Nos.
-133491, JP-A-57-83562, and the like, describe a photocurable composition containing a polyurethane (meth) acrylate. Further, the proportion of these used for printing inks, coating agents and the like is increasing.

[0003]

The oligomers are:
Due to its high viscosity, it is necessary to dilute it with a low-viscosity monomer before use. Conventionally, N-vinylpyrrolidone is often used due to the problem of adhesion to various substrates (for example, polycarbonate, poly (meth) acrylate resin, polyester resin, polyvinyl chloride, etc.). By using N-vinylpyrrolidone, it is possible to produce paints, printing inks, coating agents, adhesives, and the like having excellent curability, adhesion, etc. It thickens and gels. or,
This is a problem when the cured product is colored, especially in the case of a composition containing a white pigment (such as titanium oxide).

[0004]

Means for Solving the Problems In order to solve the above-mentioned problems, the present inventors have conducted intensive studies, and as a result, the printing ink has good stability, excellent adhesion, and little coloring of a cured product. Succeeded in providing a resin composition suitable for the present invention, and completed the present invention. That is, the present invention provides the following equation (1):

[0005]

Embedded image

A resin composition comprising a (meth) acrylate (A) represented by the formula (1), wherein R is a hydrogen atom or a methyl group, and an oligomer (B). (2) The resin composition according to (1), wherein the oligomer (B) is at least one member selected from epoxy (meth) acrylate, urethane (meth) acrylate, and polyester (meth) acrylate. (3) The resin composition according to (1) or (2) for printing inks, and (4) any one of (1) to (3) containing a photopolymerization initiator (C). Resin composition of (5)
A cured product of the resin composition according to any one of (1) to (4).

In the resin composition of the present invention, a (meth) acrylate (A) represented by the above formula (1) is used.
This (meth) acrylate (A) is, for example,
As a method, there is a method of reacting glycerin carbonate with (meth) acrylic acid, and as a second method, a method of reacting glycerin carbonate with (meth) acrylic chloride. The first method will be described.
It is preferable to use one or more of non-reactive and organic solvents such as benzene, toluene, n-hexane, n-heptane, and cyclohexane. If necessary, more water-soluble organic solvents (eg, acetone, methyl ethyl ketone, etc.) can be used for post-treatment. The use ratio of glycerin carbonate to (meth) acrylic acid is preferably about 0.9 to 5 mol, particularly preferably about 1 to 3 mol, per mol of glycerin carbonate. To accelerate the reaction, sulfuric acid,
It is preferable to use p-toluenesulfonic acid, methanesulfonic acid and the like. The reaction temperature is preferably about 80 to 150 ° C, and the reaction time is preferably about 1 to 20 hours. During the reaction,
It is preferable to use a polymerization inhibitor to prevent polymerization. Examples of the polymerization inhibitor include hydroquinone, methylhydroquinone, p-methoxyphenol, 2,6-
Examples thereof include di-t-butyl-p-cresol and phenothiazine.

Next, the second method will be explained. For example, using a reaction solvent such as chloroform, 1.0-1.2 mol of (meth) acrylic acid chloride is reacted with 1 mol of glycerol carbonate. Is particularly preferable, and 1.0 to 1.05 mol is particularly preferable. In order to accelerate the reaction, it is preferable to use a dehydrochlorinating agent such as triethylamine, trimethylamine, pyridine or the like, and the amount thereof is preferably equimolar to (meth) acrylic acid chloride. The reaction temperature is preferably about 0-30 ° C, and the reaction time is preferably about 1-5 hours. During the reaction, it is preferable to use the same polymerization inhibitors as described above to prevent polymerization.

In the composition of the present invention, the above-mentioned (meth) acrylate (A) is used. Usually, it is used together with the oligomer (B) described later. This (meth) acrylate (A) has a function as a diluent for the oligomer (B), and the viscosity of the oligomer (B) is reduced. Also,
Excellent storage stability, good curability, adhesion to substrate,
A cured product having excellent coloring properties and the like can be obtained. The oligomer (B) used in combination is an epoxy (meth) acrylate (B-1), a urethane (meth) acrylate (B-
2) and polyester (meth) acrylate (B-3).

Epoxy (meth) acrylate (B-1)
Can be obtained, for example, by reacting an epoxy resin with (meth) acrylic acid. Suitable epoxy resins are bisphenol type epoxy resins obtained by reacting bisphenol A or bisphenol F with epichlorohydrin. In addition, novolak epoxy resins such as phenol novolak epoxy resin and cresol novolak epoxy resin; aliphatic epoxy resins such as hexanediol diglycidyl ether, glycerin diglycidyl ether, and trimethylolpropane triglycidyl ether are also included. You.

Urethane (meth) acrylate (B-2)
For example, a polyol (a) and an organic polyisocyanate (b) are reacted to obtain a urethane prepolymer,
Then, a product obtained by reacting the urethane prepolymer with a hydroxyl group-containing (meth) acrylate (c) or a product obtained by reacting the organic polyisocyanate (b) with a hydroxyl group-containing (meth) acrylate (c) And the like.

Examples of the polyol (a) include ethylene glycol, propylene glycol, 1,3-butylene glycol, neopentyl glycol, 1,6-hexanediol, polypropylene glycol, bisphenol A polyethylene glycol, polytetramethylene glycol, glycerin, Examples thereof include trimethylolpropane, polyester polyol, polycarbonate polyol, polycaprolactone polyol, polybutadiene polyol, polymer polyol, and polysiloxane polyol.

The organic polyisocyanate (b) includes
Aromatic diisocyanates such as, for example, tolylene diisocyanate or diphenylmethane diisocyanate; araliphatic diisocyanates such as tetramethylxylylene diisocyanate; isophorone diisocyanate;
Examples thereof include aliphatic or cycloaliphatic diisocyanates such as bis (4-isocyanatocyclohexyl) methane, hexamethylene diisocyanate, and trimethylhexamethylene diisocyanate.

As the hydroxyl group-containing (meth) acrylate (c), for example, 2-hydroxyethyl (meth)
Monofunctional (meth) acrylate having one acrylic group such as acrylate, 2-hydroxypropyl (meth) acrylate, and 4-hydroxybutyl (meth) acrylate; trimethylolpropane di (meth) acrylate;
Examples thereof include polyfunctional (meth) acrylates having two or more acrylic groups, such as glycerin di (meth) acrylate, pentaerythritol tri (meth) acrylate, and dipentaerythritol penta (meth) acrylate.

The reaction between the polyol (a) and the organic polyisocyanate (b) is carried out in such a manner that 1.1 to 2.5 equivalents of isocyanate groups in the organic polyisocyanate (b) are added to 1 equivalent of hydroxyl groups in the polyol (a). Is preferably reacted, and particularly preferably 1.2 to 2.2 equivalents. The reaction time is preferably 5 to 20 hours. Reaction temperature is 80-1
00 ° C is preferred. Then, the hydroxyl group in the hydroxyl group-containing (meth) acrylate (c) was 0.95 with respect to 1 equivalent of the isocyanate group in the obtained urethane polymer.
The reaction is preferably performed in an amount of from 0.9 to 1.1 equivalents, and particularly preferably from 0.99 to 1.05 equivalents. Reaction temperature is 80 ~
100 ° C. is preferred. The reaction time is preferably 5 to 20 hours, and usually a catalyst is used to promote the reaction. Examples of the catalyst include dibutyltin dilaurate.

Polyester (meth) acrylate (B-
3) comprises, for example, a reaction product of a polyester polyol and (meth) acrylic acid. Suitable polyester polyols include terminally hydroxylated polyester polyols obtained from a wide range of difunctional and polyfunctional carboxylic acids and a wide range of difunctional and polyfunctional alcohols. Suitable carboxylic acids include succinic anhydride, adipic acid, phthalic anhydride, tetrahydrophthalic anhydride. Suitable alcohols include ethylene glycol, propylene glycol, neopentyl glycol, 1,6
-Hexanediol, cyclohexane-1,4-dimethanol, trimethylolpropane and trimethylolethane.

The proportion of the components (A) and (B) constituting the resin composition of the present invention is 2 to 60% by weight when (A) + (B) is 100% by weight. %, Particularly preferably 5 to 50% by weight, and the component (B) is preferably 40 to 98% by weight, particularly preferably 5 to 50% by weight.
0 to 95% by weight.

In the resin composition of the present invention, various known ethylenically unsaturated compounds are preferably used as components other than the components (A) and (B). Examples of the ethylenically unsaturated compound include N-vinylcaprolactone, a monomer having an acryl group, and the like. One or two of these ethylenically unsaturated compounds may be used, if necessary.
At least one kind of compound can be mixed and used at an arbitrary ratio. The amount of the ethylenically unsaturated compound to be used is preferably from 0 to 50% by weight, particularly preferably from 10 to 40% by weight, in the resin composition. These ethylenically unsaturated compounds are readily available on the market.

Examples of the monomer having an acryl group include tetrahydrofurfuryl (meth) acrylate, carbitol (meth) acrylate, phenoxyethyl (meth) acrylate, isobornyl (meth) acrylate, acryloylmorpholine, and 2-ethylhexyldiethoxy (meth) acrylate. A) acrylate, hydrogenated dicyclopentadiene (meth) acrylate, 2-hydroxy-3-phenyloxypropyl (meth) acrylate, tricyclodecane di (meth) acrylate, tripropylene glycol di (meth) acrylate, polyethylene glycol di (meth) A) acrylate, 1,9-nonanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, Methylolpropane polyethoxytri (meth) acrylate, trimethylolpropane polypropoxytri (meth) acrylate, glycerin polypropoxytri (meth) acrylate, bisphenol A polyethoxydi (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra ( (Meth) acrylate, ditrimethylolpropanetetra (meth) acrylate, a mixture of dipentaerythritol penta and hexa (meth) acrylate, dipentaerythritol polyethoxyhexa (meth) acrylate, dipentaerythritol polypropoxyhexa (meth) acrylate, and the like. Can be.

The resin composition of the present invention can be cured by a known method. In the case of curing by ultraviolet rays, it is necessary to use a photopolymerization initiator (C). When it is necessary to use the photopolymerization initiator (C), its amount is usually 0.1 to 15% by weight of the composition, preferably 3 to 15% by weight.
-10% by weight.

The photopolymerization initiator (C) may be any known photopolymerization initiator, but is required to have good storage stability after compounding. Examples of such a photopolymerization initiator include benzoins such as benzoin ethyl ether, benzoin butyl ether and benzoin isopropyl ether, acetophenone, and 2,2-dimethoxy-2.
-Phenylacetophenone, 2,2-diethoxy-2-
Phenylacetophenone, 1,1-dichloroacetophenone, 1-hydroxycyclohexyl phenyl ketone,
2-methyl-1- [4- (methylthio) phenyl] -2
Acetophenones such as morpholino-propan-1-one and N, N-dimethylaminoacetophenone; 2,4-
Diethylthioxanthone, 2-chlorothioxanthone,
Thioxanthones such as 2-isopropylthioxanthone; ketals such as benzyldimethyl ketal and acetophenone dimethyl ketal: benzophenones such as benzophenone, methylbenzophenone, 4,4'-bisdiethylaminobenzophenone and 4-benzoyl-4'-methyldiphenylsulfide; There are phosphine oxides such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide, which can be used alone or in combination of two or more.

Further, a photosensitizer such as a tertiary amine may be used alone or in combination with two or more kinds together with the photopolymerization initiator (C). Examples of the tertiary amines include N, N-dimethylaminobenzoic acid ethyl ester,
N, N-dimethylaminobenzoic acid isoamyl ester,
Pentyl-4-dimethylaminobenzoate, triethylamine, triethanolamine and the like can be mentioned.

The resin composition of the present invention may further contain, if desired, other components such as a coloring agent such as a pigment or a dye; a non-reactive polymer resin such as a polyester elastomer, a polyurethane elastomer, or an acrylic polymer; Additives such as a foaming agent, a silane coupling agent, an antioxidant, an ultraviolet absorber, a light stabilizer, and a polymerization inhibitor; and inorganic fillers such as talc, silica oxide, and barium sulfate can be added. When it is necessary to use the photopolymerization initiator (C), the amount used is usually 0.1 to 15% by weight of the composition.
And preferably 3 to 10% by weight.

The composition of the present invention can be prepared by mixing, heating and dissolving the components (A) and (B), if necessary, the photopolymerization initiator (C) and, if desired, other components. .

The composition containing a photopolymerization initiator is applied, for example, to the surface of a substrate and then cured by irradiating ultraviolet rays. The thickness is preferably about 2 to 30 μm. The composition can be applied on a wide range of substrates including paper, rigid and flexible plastics, metal substrates, cement, glass, stone, ceramic, wood, and others.

The composition of the present invention is suitably used for printing inks such as screen printing inks, offset printing inks, gravure printing inks, intaglio printing inks, etc. In addition, paints, adhesives, resists, lenses, It can be used for others. When the composition of the present invention is used as a screen printing ink, a screen printing method is suitable as a printing method. The substrate (for example, plastic such as polycarbonate, polyvinyl chloride, polyester, and polyacryl) is screen-printed by 10 to 30 μm.
And then cured by UV irradiation.

[0027]

The present invention will be described below in more detail with reference to examples. Parts in Examples are parts by weight. (Synthesis example of urethane (meth) acrylate (B-2)) Synthesis example 1 Polyester diol (polyester diol having molecular weight of 480 and consisting of neopentyl glycol and adipic acid)
230 parts, 244.8 parts of polytetramethylene glycol (average molecular weight: about 2000) and 200 parts of isophorone diisocyanate were charged and reacted at 85 ° C. for about 10 hours, and then 68.7 parts of 2-hydroxyethyl acrylate, p
-Methoxyphenol 0.37 parts, dilauric acid di-n
0.14 parts of -butyltin was charged and reacted at 85 ° C. for about 10 hours until the residual NCO concentration became 0.3% or less, to obtain urethane acrylate (B-2-)). The viscosity of the product was 1510 poise (60 ° C.).

Synthesis Example 2 Polytetramethylene glycol (average molecular weight 2000)
857.9 parts, tricyclodecane dimethylol
7 parts and 620.4 parts of isophorone diisocyanate were reacted at 85 ° C. for about 10 hours, and then 334 parts of 2-hydroxyethyl acrylate, 1.0 part of p-methoxyphenol and 0.4 parts of di-n-butyltin dilaurate were added.
The reaction was carried out at 85 ° C. for about 10 hours until the residual NCO concentration became 0.3% or less to obtain urethane acrylate (B-2-). The viscosity of the product is 800
It was 0 poise (60 ° C.).

Synthesis Example 3 384 parts of polyester diol (average molecular weight of 480 composed of neopentyl glycol and adipic acid), propylene glycol modified polytetramethylene glycol (manufactured by Hodogaya Chemical Co., Ltd., PPTG-2000, average molecular weight 2)
000) and Coronate 2094 (manufactured by Nippon Polyurethane Co., Ltd., diisocyanate compound, 1 mol of hydrogenated bisphenol A and hexamethylene diisocyanate 2)
864 parts, reacted at 85 ° C. for about 10 hours, and then charged 176.4 parts of 2-hydroxyethyl acrylate and 0.9 part of p-methoxyphenol, About 15 hours at 85 ° C, residual N
The reaction was carried out until the CO concentration became about 0.3% or less to obtain urethane acrylate (B-2-). The viscosity of the product was 6,800 poise (60 ° C.).

Synthesis Example 4 (Synthesis example of (meth) acrylate (A)) 118 parts of glycerin carbonate, triethylamine 1
01 parts, 2,6-di-t-butyl-p-cresol 1 part and chloroform 400 parts were charged, and 90.5 parts of acrylic acid chloride was added over about 1 hour while stirring and maintaining at 0 to 10 ° C. It was added dropwise and kept at this temperature for 2 hours. After completion of the reaction, triethylamine hydrochloride was filtered, and 5
The solution was washed successively with a 1% aqueous hydrochloric acid solution and water, and chloroform was removed under reduced pressure to obtain 163 parts of a product (2,3-carbonate propyl acrylate). Product viscosity (25
° C) 335 cps and refractive index (25 ° C) is 1.4713
Met. The measurement results by NMR were as follows.

Table 1 No.Hz ppm No.Hz ppm 1 12507.3 165.743 6 5584.0 73.997 2 11693.5 154.958 7 5000.0 66.259 3 10019.3 132.773 8 4993.2 66.168 4 9618.7 127.465 9 4781.1 63.357 5 5594.3 74.134 10 0.3 0.003

Examples 1 to 3 and Comparative Example 1 Each component was mixed according to the formulation shown in Table 2 (the numerical values indicate parts by weight) and kneaded with a three-roll mill to obtain a resin composition (printing ink composition). ) Was prepared. The stability, curability, colorability and adhesion of the cured product were evaluated, and the results are shown in Table 2. The evaluation was performed by the following method.

Curability: 200 μm in thickness of prepared composition
Is printed by a screen printing method (thickness: 15 μm) on an easy-adhesive polyester sheet, and then irradiated by a high-pressure mercury lamp (lamp output: 2 kW) at a position of 8 cm under a light source arranged in parallel (conveyor speed: 20 m / min) and cured. Was.
The irradiation dose (mJ / cm ² ) until curing was determined.

Colorability: 9% of the printed matter cured by the above method
After standing at 0 ° C. for 24 hours, the degree of coloring of the printed surface was observed.・: Almost no discoloration. Δ: Some discoloration. ×: Discoloration is remarkable.

Adhesion: The printed matter cured by the above method was subjected to a cross-cut cellophane tape peeling test.・: No peeling eyes and no missing eyes occur. Δ: Some missing eyes are observed. X: peeling eyes and chipped eyes occurred.

Liquid stability: 100 g of the prepared composition
Was placed in a brown 100 ml polyvin, left at 70 ° C., and after 30 days, the presence or absence of gelation was observed.・: Not gelled. X: Gelled.

Table 2 Example Comparative Example 1 2 3 1 Urethane acrylate (B-2-) obtained in Synthesis Example 1 28 28 Urethane acrylate (B-2-) obtained in Synthesis Example 2 30 Obtained in Synthesis Example 3 Urethane acrylate (B-2-) 28 Acrylic ester obtained in Synthesis Example 4 42 40 42 N-vinylpyrrolidone 42 1-hydroxycyclophenyl ketone (photopolymerization initiator) 33 33 Irgacure 907 * 1 (photopolymerization Initiator) 11 11 2-isopropylthioxanthone (photopolymerization initiator) 0.2 0.2 0.2 0.2 p-methoxyphenol (polymerization inhibitor) 0.1 0.1 0.1 0.1 Titanium dioxide (white pigment) 30 30 30 30 ---- −−−−−−−−−−−−−−−−−−−−−−−−−−−−− Curability (mJ / cm ² ) 70 70 70 138 Colorability ○ ○ ○ × Adhesion ○ ○ ○ ○ Stability of liquid ○ ○ ○ ×

Note) * 1: Irgacure 907: 2-Methyl-1- [4- (methylmeo) phenyl] -2-morpholino-propane-1-manufactured by Ciba Specialty Chemicals Co., Ltd.
on.

From the evaluation results shown in Table 2, the resin composition using the novel (meth) acrylic acid ester of the present invention is excellent in stability, the cured product is less colored and the adhesion is good.

[0040]

The resin composition of the present invention has good stability of the composition, little coloring of the cured product and good adhesion.
Particularly suitable for printing inks.

Continued on the front page F-term (reference) 4J011 QA03 QA33 QA37 QB14 QB19 QB23 SA01 SA21 SA34 SA51 SA64 SA83 SA84 UA01 WA01 WA02 4J027 AA02 AB01 AE04 AG02 AG03 AG04 AG05 AG15 AG23 AG24 AG27 AG32 BA07 CB10 CC05 CD08 CDAE04BC03 BC16 BC31 BC54 BC55 BC56 BC68 BE27 EA05 EA43 EA44 FA01 FA02 FA04 FA05 FA06 FA07 GA02 GA03 GA10

Claims (5)

[Claims] (1) The following formula (1): (In the formula (1), R is a hydrogen atom or a methyl group.) A resin composition comprising a (meth) acrylate (A) and an oligomer (B) represented by the formula: 2. The resin composition according to claim 1, wherein the oligomer (B) is one or more selected from epoxy (meth) acrylate, urethane (meth) acrylate, and polyester (meth) acrylate. 3. The resin composition according to claim 1, which is for a printing ink. 4. The resin composition according to claim 1, further comprising a photopolymerization initiator (C). 5. A cured product of the resin composition according to any one of claims 1 to 4.