JPS63142006A - Photocurable resin composition - Google Patents

Abstract

PURPOSE:To provide a composition, outstanding in adhesivity to objects to be coated such as glass, high in curing rate, capable of forming coating film of high water resistance, etc., comprising an ester from hydantoin type diol an (meth)acrylic acid polymerizable compound and photopolymerization initiator. CONSTITUTION:The objective composition comprising (A) an ester from a hydantoin type diol [e.g., a compound of formula (R1 and R2 are each H or CH3; R3 and R4 are each 1-5C alkyl, etc., m and n are each 1-4)] and (meth) acrylic acid. (B) a polymerizable compound other than the component A, containing in one molecule at least one polymerizable C=C bond (e.g., diallyl adipate, N,N-dimethylamino-ethyl acrylate), and (C) a photopolymerization initiator (e.g., benzoin, anthracene) in such amounts as to be, in general, 1-5pts. by wt. per 100pts. by wt. of the components A plus B, of the component C. this composition can be used in printed circuit based plates coating materials for electronic parts, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to a photocurable resin composition useful as a coating material for printed circuit boards, electronic parts, and the like.

[Conventional technology]

Photocurable resin compositions save resources and energy.

In recent years, it has attracted particular attention as a curable material that can replace conventional thermosetting materials using organic solvents from the viewpoint of being non-polluting.

Various types of photocurable resin compositions are known that use epoxy (meth)acrylate oligomers, polyester (meth)acrylate oligomers, urethane (meth)acrylate oligomers, etc. as main components. Since those using meth)acrylate oligomers provide cured coatings with good mechanical strength, they are expected to be applied to various uses such as printed circuit boards and coating materials for electronic parts.

[Problem that the invention seeks to solve]

However, the conventionally known photocurable resin compositions as described above have poor adhesion to inorganic substances such as glass and metals, have poor curability, and furthermore, the water resistance and heat resistance of the cured coating film are not sufficient. Ta. For this reason, although it has various advantages of being photocurable, the current situation is that its application to various uses has not progressed dramatically.

Therefore, the present invention solves the above-mentioned conventional problems and provides a printing method that can form a cured coating film with good adhesion and water resistance and heat resistance on the surface of inorganic materials such as glass and metals. The object of the present invention is to provide a photocurable resin composition particularly useful as a coating material for circuit boards and electronic components.

[Means for solving problems]

As a result of intensive studies to achieve the above object, the inventors found that esters of hydantoin diol and (meth)acrylic acid and various other polymerizable compounds were used as the main components of the photocurable resin composition. When used in combination, by applying this to an inorganic material such as glass or a metal surface and irradiating it with light such as ultraviolet rays, it is possible to create a product that has excellent adhesion to the surface of the object to be coated and has good water resistance and heat resistance. It was discovered that a cured coating film with good curability could be formed, and this invention was made.

That is, this invention provides a) an ester of a hydantoin diol and (meth)acrylic acid, b) a polymerizable compound other than the above component a containing one or more polymerizable carbon-carbon double bonds in one molecule, C ) The present invention relates to a photocurable resin composition characterized by containing a photopolymerization initiator.

In addition, in this specification, the (meth)acryloyl group refers to an acryloyl group and/or a methacryloyl group,
(Meth)acrylate means acrylate and/or methacrylate, (meth)acrylic acid means acrylic acid and/or methacrylic acid, and viscosity means a value measured by a Brookfield viscometer.

[Structure and operation of the invention]

The ester as component a used in this invention is
A hydantoin type diol and (meth)acrylic acid are usually used as a catalyst in an amount of 0.1 to 10% by weight, preferably 0.5 to 10% by weight of an acidic compound such as hydrochloric acid, sulfuric acid, or p-toluenesulfonic acid.
A compound containing two (meth) molecules in the molecule, obtained by esterification reaction at 80 to 120°C for 5 to 20 hours in the presence of a polymerization inhibitor such as hydroquinone, using It is a compound containing an acryloyl group.

The above-mentioned hydantoin-type diol is a diol derived from hydantoin or its substituted product, and a typical example is a hydantoin substituted with an alkyl group at the 5-5 position, to which ethylene oxide or propylene oxide is added. There is a di(hydroxyalkyl)hydantoin represented by the following formula which is obtained by reaction.

R.

■ 0=CN(CHz -CHO)-, H (wherein R,, R2 are hydrogen or methyl group, R
3 and R4 are each an alkyl group having 1 to 5 carbon atoms, or a pentamethylene group that together forms a cyclohexane ring with the 5th carbon of the hydantoin, and m and n are each (an integer of 1 to 4) The polymerizable compound used as component b used in this invention is the above-mentioned a
The components mainly improve the adhesion, water resistance, and heat resistance of the cured coating film to glass and metal, and also contribute to the improvement of curability, whereas the elongation of the cured coating film 1 mechanical strength.

It is used to adjust physical properties such as flexibility, and also serves as a reactive diluent for component a to adjust the viscosity of the composition.

Component b broadly includes polymerizable compounds containing one or more polymerizable carbon-carbon double bonds in one molecule,
Its molecular weight is generally about 90 to 5,000. A typical example of this b component is (
There are (meth)acrylate compounds having a meth)acryloyl group.

Specific examples of the above (meth)acrylate compounds include 2
- Ethylhexyl (meth)acrylate, tetrahydrofurfuryl alcohol caprolactone adduct (meth)
Acrylate, (meth)acrylate of nonylphenol ethylene oxide adduct, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, bisphenol diethylene glycol di(meth)acrylate, hydrogenated bisphenol triethylene glycol di(meth)acrylate , alicyclic di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri
Examples include (meth)acrylate.

As component b, in addition to the above-mentioned (meth)acrylate compounds, allyl esters such as diallyl adipate, diallyl phthalate, and triallyl isocyanurate, styrene, vinyl acetate, N-vinylpyrrolidone, N-N
Various vinyl compounds such as -dimethylacrylamide, N-N-dimethylaminopropylacrylamide, and N-N-dimethylaminoethyl acrylate can be used.

The ratio of components a and b used in this invention is determined by the viscosity of the composition, the physical properties of the cured coating, etc., but if the amount of component C is too small, the adhesion and water resistance of the cured coating to glass, metal, etc. ``In addition to deteriorating heat resistance, curability also deteriorates; conversely, if too much is used, the cured coating film becomes hard and physical properties such as toughness deteriorate. In order to satisfy all of these characteristics, it is desirable that the proportion of component C in the total amount of components a and b be 3θ to 90% by weight, preferably 40 to 80% by weight.

As the photopolymerization initiator used as component C in this invention, various kinds of initiators generally used as initiators and aggravating agents for ultraviolet curable coatings can be used. For example, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, 2-methylbenzoin, benzophenone, Michler's ketone, benzyl, benzyl dimethyl ketal, benzyl diethyl ketal, anthraquinone, methylanthraquinone, 2,2-jethoxyacetophenone , 2-methylthioxanthone, 2-isopropylthioxanthone, 2-chlorothioxanthone,
Examples include anthracene, 1.1-dichloroacetophenone, methylorthobenzoylbenzoate, and those used in combination with small amounts of sensitizing aids such as amines.

The amount of these photopolymerization initiators to be used is usually about 0.1 to 10 parts by weight, preferably 1 to 5 parts by weight, based on 100 parts by weight of the total amount of components a and b. If this amount is too small, the curability cannot be satisfied, and even if it is used in excess of a predetermined amount, no further improvement in the curing rate can be expected.

The photocurable resin composition of the present invention may optionally contain various modifying resins such as acrylic resin, polyamide resin, polyester resin, polyether resin, polyurethane resin, silicone resin, and phenol resin, as well as organic silicon compounds, Various additives such as surfactants may be added, and the viscosity of the entire composition is usually from 10 to 10, from the viewpoint of coating workability.
It is desirable that the temperature be adjusted within the range of 10,000 centivoise (cps) (25° C.).

When using the photocurable resin composition of the present invention, for example, the thickness of the surface of the object to be coated after curing is usually 10 to 2.
After applying it by an appropriate means to a thickness of 00 μm, the coated surface may be cured by irradiating it with a high-pressure mercury lamp of about 80 to 120 W/piece at an irradiation dose of 10 to 500 mJ/aa. . As a result, it is possible to form a cured coating film having excellent adhesion to the surface of the object to be coated, such as glass or metal, and having excellent water resistance and heat resistance.

〔Effect of the invention〕

As described above, the photocurable resin composition using the a, b, and c components of the present invention has a fast curing speed, good adhesion to coated objects such as glass and metal, and has water resistance and Because it can form a cured coating film with excellent heat resistance,
It can be advantageously applied to various uses such as printed circuit boards and coating materials for electronic parts.

〔Example〕

EXAMPLES Below, examples of the present invention will be described in more detail. In addition, in the following, parts shall mean parts by weight.

Example 1 1,3-di(2-hydroxyethyl)-5,5-dimethylhydantoin [R,, R2=hydrogen, R3 in the above formula
, R4'' methyl group, m, diol with n=1] and 2 moles of acrylic acid were combined with 5 parts of P-toluenesulfonic acid, 0.01 part of hydroquinone, and an amount of benzene that can remove the produced water. After reacting at 90-110° C. for 15 hours in the presence of the ester, it was washed with water and benzene was removed under reduced pressure to obtain an ester containing two acryloyl groups in the molecule (hereinafter referred to as ester A).

50 parts of alicyclic diacrylate (trade name 5A1002 manufactured by Mitsubishi Yuka Fine Co., Ltd.) and 2 parts of benzyl dimethyl ketal were mixed with 50 parts of the above ester A, and the mixture had a viscosity of 450 cp.
A photocurable resin composition of 25° C. was obtained.

Example 2 50 parts of bisphenol diethylene glycol diacrylate and 2 parts of benzyl dimethyl ketal were mixed with 50 parts of ester A obtained in Example 1, and the mixture had a viscosity of 700 cps.
(25° C.) A photocurable resin composition was obtained.

Example 3 20 parts of N-vinylpyrrolidone and 2 parts of benzyl dimethyl ketal were mixed with 80 parts of the ester A obtained in Example 1 to obtain a photocurable resin composition with a viscosity of 220 cps (25°C).

Example 4 Instead of 1,3-di(2-hydroxyethyl)-5,5-dimethylhydantoin, ■,3-di(2-hydroxyethyl)-5,5-pentamethylenehydantoin [R in the above formula ,, R, = hydrogen, R3, RJ = pentamethylene group in which both groups together form a cyclohexane ring with the 5-position carbon of hydantoin, diol with m and n = 1] were used in the same amount. An ester (hereinafter referred to as ester B) was obtained in the same manner as in Example 1.

Using this ester B, a photocurable resin composition having a viscosity of 450 cps (25° C.) was obtained with the same formulation as in Example 1.

Example 5 Instead of 1,3-di(2-hydroxyethyl)-5,5-dimethylhydantoin, 1,3-(γ-hydroxypropyl)-5,5-diethylhydantoin [R in the above formula, R2=methyl group, R:1. R4=ethyl group,
An ester (hereinafter referred to as ester C) was obtained in the same manner as in Example 1, except that the same amount of diol with m and n=1 was used.

Using this ester C, a photocurable resin composition with a viscosity of 600 cps (25° C.) was obtained with the same formulation as in Example 1.

Comparative Example 5 100 parts of A1002 (described above) and 2 parts of benzyl dimethyl ketal were mixed to obtain a photocurable resin composition with a viscosity of 7 Qcps (25°C).

Each of the photocurable resin compositions of the above examples and comparative examples,
It was coated on a glass plate to a thickness of lO to 20 μm and cured by light irradiation using a high-pressure mercury lamp (80w/C0I). The adhesion, heat resistance, and water resistance of the film were examined. The results were as shown in the table below. Note that adhesion, heat resistance, and water resistance were measured by the following methods.

<Adhesion> 100 dimples are made on the cured coating film at intervals of 1 am,
A pressure-sensitive adhesive tape (trade name No. 21, manufactured by Nitto Electric Industry Co., Ltd.) was crimped onto this, and the number of pieces remaining when the tape was peeled off was examined.

<Heat resistance> 100 cuts are made in the cured coating film at 1 fin intervals, and 80
After being left in the air at .degree. C. for 30 days, a pressure-sensitive adhesive tape (trade name No. 21, manufactured by Nitto Electric Industry Co., Ltd.) was crimped thereon, and the number of pieces remaining when the tape was peeled off was examined.

Water resistance> The cured coating film was immersed in warm water at 80℃ for 24 hours, and the condition of the coating film at this time was examined. If the coating film adhered well to the glass surface, it was evaluated as ○, and the coating film did not peel off. Cases in which this occurred were rated as ×.

As is clear from the above test results, the photocurable resin composition according to the present invention has a fast curing speed, excellent adhesion to glass plates, and is water resistant.

It can be seen that this material provides a cured coating film with excellent heat resistance.

Claims (1)

[Claims] (1) a) Ester of hydantoin type diol and (meth)acrylic acid, b) Polymerizable compound other than the above component a containing one or more polymerizable carbon-carbon double bonds in one molecule, c
) A photocurable resin composition comprising a photopolymerization initiator.