JPS60147484A - Ink composition for screen printing curable with active rays - Google Patents

Abstract

PURPOSE:The titled composition that is composed of a reaction product from an epoxy compound and an aromatic monocarboxylic acid and an unsaturated compound having a polymerizable double bond, thus being readily curable by irradiation with ultraviolet rays or the like in a short time and showing good processability such as high adhesion to base materials and folding properties. CONSTITUTION:The objective composition is obtained by using (A) a reaction product from (i) an epoxy compound having 1 or more epoxy groups per molecule (such as bisphenol type or novolak type of 200-4,000mol.wt) and (ii) an aromatic monocarboxylic acid free from polymerizable double bonds, preferably the product softening below 120 deg.C, (B) an unsaturated compound bearing polymerizable double bonds and, when necessary, (C) a radical polymerization initiator.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ink composition for silk screen printing that can be easily converted into active energy rays.
Moreover, the present invention relates to an ink composition that has excellent adhesion to substrates and processability such as foldability.

In recent years, research on compositions curable with active energy rays has
It is actively being carried out from the viewpoints of energy saving, resource saving, and prevention of air pollution, and among these, practical application is progressing in the field of one-ink printing (for example, Japanese Patent Application Laid-Open No. 128067/1983).

Kowara consists of a radically polymerizable prepolymer and monomer and, if necessary, a radical polymerization initiator. Examples of the prepolymer include alkyd acrylate, polyester acrylate, epoxy acrylate, urethane acrylate, etc. As monomers, acrylates of aliphatic alcohols, acrylates of alkylene oxide adducts of phenolic hydroxyl groups, acrylates of glycidyl compounds, etc. are used. However, alkyd acrylates are plasticized by resin acids, resulting in a softened cured film and poor solvent resistance. Epoxy acrylate has excellent curability but poor adhesion. In addition, acrylate using a polyisocyanate medium of fatty acid-modified alkyd has poor workability because it becomes highly viscous due to the urethane bonds in the molecule.In order to lower the viscosity, the proportion of monomer as a reactive diluent increases, resulting in poor curing. It had disadvantages such as causing

``Also, when using these active energy ray-curable compositions as an ink tack for silk screen printing, adjusting the ink viscosity may cause problems such as difficulty in achieving a balance between adhesion and processability.'' Therefore, a method has been considered in which a resin that does not have radical polymerizability is added to the composition for the purpose of increasing adhesiveness, workability, etc. -23
Publication No. 812, etc.). Problems such as stiffness, stiffness, and strong ink tack are still unsatisfactory, and workability is significantly reduced.

As a result of intensive research aimed at improving these drawbacks, the inventors of the present invention have developed a material that has excellent curing properties, excellent adhesion to metal plates, painted metal plates, various glass films, etc., and is flexible. , 1. Processability and printing suitability, which is important for silk screen printing,
For example, we have succeeded in obtaining an ink composition that has sufficient performance and leveling properties, resulting in the present invention.

That is, the present invention provides a reaction product of r (a) an epoxy compound having one or more epoxy groups per molecule and an aromatic monocarboxylic acid having no polymerizable double bond (bl having a polymerizable double bond ff Unsaturated compound (c)
It is an active ray-curable silicic acid product that is characterized by containing a radical polymerization initiator if necessary.

In the present invention, epoxy compounds refer to epoxy resins, glycidyl ester type epoxy resins; glycidyl amine type epoxy resins, linear aliphatic epoxy resins, alicyclic epoxy resins, and glycidyl ester type epoxy resins; Resin etc. can be suitably used. Examples of the glycidyl ether type epoxy resin include bisphenol A diglycidyl ether, bisphenol A di-β methyl glycidyl ether, bisphenol F diglyphidyl ether,
There are bisphenol A alkino boral lyph glycidyl ether, polyalkylene glycol sidalicidyl ether, epoxy urethane tree 111, etc., and glycidyl ester type epoxy resin In& includes phthalic acid diglycidyl ester, rimer acid diglycidyl ester, etc. ,
Glycidylamine type epoxy resins include triglycidyl isocyanurate, linear aliphatic epoxy resins include epoxidized polybutadiene, epoxidized soybean oil, etc., and alicyclic epoxy resins include bis(3 , 4-epoxy-6-methylcyclohexylmethyl)adipate, 3,4-epoxy-6-methylcyclohexylmethyl, 3,4-epoxy-6-methylcyclohexanecarboxylate, etc., all of which can be used. However, in order to particularly improve processability, it is preferable to use a bisphenol-rutaib epoxy compound.

The molecular weight range of the epoxy compound is preferably 200 to 4,000. If an epoxy compound with a molecular weight lower than 200 is used, the viscosity of the obtained reaction product (a) will be low, so the amount of unsaturated compound (bl) containing polymerizable double bond gold will be reduced, and the nitrified film will be formed. It's getting weaker and I'm sorry.

In addition, if a compound with a molecular weight exceeding 400 (l) is used, the viscosity of the reaction product (a) obtained will increase, and therefore the amount of unsaturated compound (b) used will increase7, which will increase the crosslinking density and increase the adhesion. Deterioration in properties and workability is observed, which is not preferable.

What is an aromatic monocarboxylic acid that does not have a polymerizable double bond?
In general, derivatives of benzoic acid can be used, such as alkyl-substituted benzoic acids such as benzoic acid, methylbenzoic acid, propylbenzoic acid, and nitrobenzoic acid. Also, α,
Condensed carboxylic acids such as β-naphthenic acid and anthranilic acid can also be used.

The reaction between an epoxy compound and an aromatic monocarboxylic acid is 70
It can be carried out at a temperature in the range of 300°C to 300°C under an inert gas flow, and the amount of carboxylic acid group is 0.5% per equivalent of epoxy group.
It is preferable to react in an amount of 5 equivalents or more in order to improve adhesiveness. Further, a catalyst can also be used in this esterification reaction. As a catalyst, it is possible to react at a low temperature by using an amine catalyst in the ring-opening reaction of an epoxy group, and the reaction with a secondary hydroxyl group after ring-opening esterification can be performed at a high temperature of 2oO to 309℃. Alternatively, the reaction can be carried out at 200° C. or lower using an acid catalyst. A solvent is used as necessary to remove water generated by the reaction and to prevent the reaction vessel from burning.

Moreover, the softening point of the reaction product (a) of the epoxy compound and the aromatic monocarboxylic acid is preferably 120° C. or lower. When the softening point is higher than 120°C, a large amount of unsaturated compound (b) is required, processability deteriorates, and the reaction product (a)? It is preferable because gelation tends to occur when diluting with the unsaturated compound (b). <No.

The reaction product of an epoxy compound and an aromatic monocarboxylic acid (al) and the unsaturated compound (bl) are not particularly limited in proportion, but are preferably (a) 1o to 88.
1. )2o~90! ! :1%,! : &, b, r
Good blending ratio.

Unsaturated substances with polymerizable double bonds (0) are acrylic acid or methacrylic acid ester monomers that add alkylene oxides such as ethylene oxide and propylene oxide to phenols such as ali, phenol, alkylphenol, resorcinol, and bisphenol. It is a (meth)acrylic acid ester monomer obtained by esterifying , acrylic acid, or methacrylic acid.

In the present invention, when the active energy ray is ultraviolet rays, it is necessary to add all the radical polymerization initiators (photosensitizers), including benzoin, pen, twin methyl ether, benzoin ethyl ni, thyl, and benzoin iso-10 vinyl. 4. Benzoin sensitizers such as ether, α-chlorobenzoin and α-acrylic benzoin; aryl ketone sensitizers such as benzophenone, p-methylbenzophenone, p-chlorobenzophenone, methyl 0-benzoylbenzoate and acetophenone; 4. Dialkylaminoaryl ketone sensitizers such as 4'-bisdiethylaminobenzophenone, p-thumef/l/7-isoamyl benzoate, p-tsumethylaminoacetophenone, polycyclic carbonyls such as thioxanthone, xanthone, and their halogen-substituted products The sensitizers may be used alone or in appropriate combinations.

These photosensitizers can be used in the a-paraboloid in an amount of 0 to 30% by weight, preferably 0 to 15% by weight.

In the present invention, organic or inorganic pigments,
Extender pigments, plasticizers, various resins, organic solvents, curing accelerators, antifoaming agents, surfactants, etc. can be added.

Further, other monomers and prepolymers may be used in combination as long as they do not completely inhibit the effects of the present invention.

Below, Himi BEI will be explained using a specific example. All parts in the examples indicate parts by weight.

Synthesis Example 1 248 parts of Epicoat 1001 (bisphenol type epoxy mat, epoxy mat 11568 manufactured by Shell Chemical Co., Ltd.),
61.1 parts of benzoic acid and 74.3 parts of triethylamine were added and heated at 100 to 120°C while blowing nitrogen gas.
411-IIn(A-) was reacted for several hours.

The acid value of the resin (Al) was 1.8, and the molecular weight was measured by GPC and was 498 in terms of styrene.The softening point was measured by TMA method and was 65°C.

Synthesis Example 2 Epicote 1004 (epoxy equivalent: 983) 196
．． 4 parts, 35.6 parts of pt-butylbenzoic acid, and 3.0 parts of triethylamine were charged and reacted in the same manner as in Synthesis Example 1 to obtain a resin. The acid value of (in the resin) is 3.0, the molecular weight is]
032, the softening point was 52°C.

Synthesis example 3 DEN438 (Dow chemical acid novolac type epoxy resin, epoxy equivalent: 1923192 parts, benzoic acid 12
2 parts and 2.9 parts of triethylamine were charged, and the reaction was carried out in the same manner as in Synthesis Example 1 to obtain a resin (Cl).The resin (e) had an acid value of 0.8, a molecular weight of 1208, and a softening point of 32°C.

Synthesis Example 4 192 parts of Epicote 828 (epoxy equivalent: 192), 72 parts of acrylic acid, 0.5 part of triethylamine, 0.25 parts of hydroquinone! Bffi preparation, under air blowing, 11
The mixture was reacted at 0° C. for 24 hours, and after confirming that the acid value was 5.0, it was taken out to obtain 411 fat (d). The viscosity of resin (d) was 167.00 at 40°C using a B-type viscometer.
It was 0C'p8.

Example Sample A1.3.5 shown in Table 1 was used as an example and sample 17, and sample &7 was used as a comparative example. Each composition was printed on a 100μ thick untreated polyethylene terephthalate film using a 350mm, 7mm silk screen plate to a thickness of 20μ. At a distance of 180W10n at a distance of 10cm under an ozone-less type high-pressure mercury lamp, 5m/
It was cured at a speed of 1 minute. Table 2 shows the results of physical property tests of this cured printed film.

Table 1 Note) Unsaturated compounds (1) Bisphenol A diacrylate with ethylene oxide addition Unsaturated compound (2) Phenol ethylene oxide addition acrylate, unsaturated compound (3) Dipentaerythritol hexaacrylate sensitizer (4) Dipentaerythritol hexaacrylate sensitizer Isoglobil thiozane/
II) BM/Irgacure-651=2:l:2'Table 2 Note") (1) Sample A2.4.6 shown in Table 1 was used as an example, and sample A8 was used as a comparative example. Each composition was irradiated with IgR4rad on an untreated polyethylene terephthalate film using a 350-mesh silk screen plate using a curtain beam electron beam irradiation device to create a cured film.This cured printed film Table 3 shows the results of the property test.

Claims (1)

[Scope of Claims] 1(a) A reaction product of an epoxy compound having one or more epoxy groups per molecule and an aromatic monocarboxylic acid having no polymerizable double bond) having a polymerizable double bond An active energy ray-curable ink composition for silk screen printing, which comprises an unsaturated compound (c) and a radical polymerization initiator if necessary. 2. The active energy-curing ink composition for silk screen printing according to claim 1, wherein the epoxy compound has a molecular weight of 200 to 4,000. 3. The active energy ray-curable silk screen printing ink composition according to claim 1 or 2, wherein the epoxy compound is at least one selected from bisphenol type epoxy compounds and novolac type epoxy compounds. 4 Active energy ray-curable silk screen printing according to any one of claims 1 to 3, wherein the reaction product of an epoxy compound and an aromatic monocarboxylic acid (al has a softening point of 120°C or lower) Ink composition for use.