JPS6354420A - Photocurable resin composition - Google Patents

Abstract

PURPOSE:To obtain the title composition which can give a cured film excellent in adhesion to glass, metal, etc. and water resistance, by mixing a reaction product of a glycidylamine with (meth)acrylic acid with a specified polymerizable compound and a photopolymerization initiator. CONSTITUTION:A glycidylamine of formula I, II or III (wherein Y is a group of formula IV), obtained by reacting epichlorohydrin with a prim. or sec, amine is reacted with (meth)acrylic acid at 60-120 deg.C for 2-10hr in the presence of a catalyst or a polymerization initiator to obtain a reaction product (A) having at least three (meth)acryloyl groups on molecular ends. 100pts.wt. in total of 10-80wt% component A and 90-20wt% polymerizable compound (B), other than component A, containing a polymerizable C-C double bond in the molecule [e.g., 2-ethylhexyl (meth)acrylate] is mixed with 0.1-10pts.wt. photopolymerization initiator (C) (e.g., benzoin) to obtain a photopolymerizable resin composition of a viscosity (at 25 deg.C) of 10-10,000cP.

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 that use 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. Products using meth)acrylate oligomers provide cured coatings with good mechanical strength, so they are expected to be applied to various uses such as printed circuit boards and coating materials for electronic components.

[Problem that the invention seeks to solve]

However, all of the conventionally known photocurable resin compositions described above have poor adhesion to inorganic materials such as glass and metals, have poor curability, and furthermore, the water resistance of the cured coating film is not sufficient. . 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 printed circuit boards and electronic components that can form cured coatings with excellent adhesion and water resistance on the surfaces of inorganic materials such as glass and metals. The purpose of the present invention is to provide a photocurable resin composition that is particularly useful as a coating material.

[Means for solving problems]

As a result of intensive studies to achieve the above object, the inventors discovered that a reaction product of glycidylamine type epoxy and (meth)acrylic acid and various other polymers were used as the main components of the photocurable resin composition. When used in combination with a chemical compound, by applying it to an inorganic material such as glass or a metal surface and irradiating it with light such as ultraviolet rays, it can be used in combination with a chemical compound that has excellent adhesion to the surface of the object and has good water resistance. It was discovered that a cured coating film with good curability could be formed, and this invention was made.

That is, this invention is directed to a) a reaction product of a glycidylamine type epoxy and (meth)acrylic acid, b) a polymerizable component other than the above-mentioned component a, which contains one or more polymerizable carbon-carbon double bonds in one molecule. The present invention relates to a photocurable resin composition characterized by containing a compound (C) and 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 reaction product as component a used in this invention is a mixture of glycidylamine type epoxy and (meth)acrylic acid at 60 to 120°C for 2 to 10 hours in the presence of a catalyst such as an amine compound or a polymerization inhibitor such as hydroquinone. It is a compound containing at least 3, usually 4 (meth)acryloyl groups at the end of the molecule, which is obtained by reacting for a period of time.

The above-mentioned glycidylamine-type epoxy is obtained by reacting shrimp chlorlyhydrin with a primary or secondary amine, and representative examples include the following 2(1):
There is an epoxy compound represented by (21, (3)).

The polymerizable compound used as component b used in this invention is a component that mainly improves the adhesion and water resistance of the cured coating film to glass and metal, and also contributes to improving curability. On the other hand, the elongation of the cured coating 2
It is used to adjust physical properties such as mechanical strength and 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, nonylphenol ethylene oxide adduct (meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, bisphenol diethylene glycol di(meth)acrylate, hydrogenated bisphenol triethylene glycol di(meth)acrylate, fat Cyclic 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 a is too small, the adhesion and water resistance of the cured coating to glass, metal, etc. In addition to this, the curability also deteriorates, and 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,
The proportion of a component in the total amount of a and b components is 10 to 8
It is desirable that the amount is 0% by weight, preferably 20 to 70% 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, methyl orthobenzoylbenzoate, 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 0.1 to 10 parts by weight, based on the total amount of components a and b. f
It is about i part, preferably 1 to 5 parts by weight. 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 to a range of 10,000 centivoises (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.
00 μm, and then cure the coated surface by irradiating it with a high-pressure mercury lamp of about 80 to 120 W/mark at a dose of 10 to 500 mJ/cal. . As a result, a cured coating film with excellent adhesion and water resistance can be formed on the surface of the object to be coated, such as glass or metal, with good curability.

〔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 good water resistance. Since it can form an excellent cured coating film, 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 mole of tetraglycidyldiaminodiphenylmethane represented by the above formula (11) and 4 moles of acrylic acid were reacted at 90 to 110°C for 5 hours in the presence of 0.5 part of triethylamine and 0.01 part of hydroquinone, Acid value (sample 1g
The number of KOH required to neutralize the reaction mixture was reduced to 2 or less to obtain a reaction product containing 4 acryloyl groups at the end of the molecule.

To 50 parts of the above reaction product, 50 parts of alicyclic diacrylate (trade name 5A1002 manufactured by Mitsubishi Yuka Fine Co., Ltd.) and 2 parts of benzyl dimethyl ketal were mixed, and the mixture had a viscosity of 3.000.
A photocurable resin composition of apl (25° C.) was obtained.

Example 2 1 mole of tetraglycidyl metaxylene diamine represented by the above formula (2) and 4 moles of acrylic acid were reacted in the same manner as in Example 1 until the acid value became 2 or less, and acryloyl was added to the end of the molecule. A reaction product containing 4 groups was obtained.

50 parts of 5A1002 (mentioned above) and 2 parts of benzyl dimethyl ketal were mixed with 50 parts of this reaction product, and the viscosity was 8.
A photocurable resin composition of 00 cps (25° C.) was obtained.

Example 3 Tetraglycidyl-1,3- represented by the above formula (3)
1 mol of bisaminomethylcyclohexane and 4 mol of acrylic acid
The reaction product was reacted in the same manner as in Example 1 until the acid value became 2 or less to obtain a reaction product containing 4 acryloyl groups at the end of the molecule. To 50 parts of this reaction product, 5A1
002 (supra) and 2 parts of benzyl dimethyl ketal were mixed to obtain a photocurable resin composition with a viscosity of 400 cps (25°C).

Comparative Example 5 100 parts of A1002 (mentioned above) and 2 parts of benzyl dimethyl ketal were mixed to give a viscosity of 7 Qcps (25°C).
A photocurable resin composition was obtained.

Each of the photocurable resin compositions of Examples 1 to 3 and Comparative Examples above was applied to a thickness of 10 to 20 μm on a glass plate, and completely cured by light irradiation using a high-pressure mercury lamp (80 w/cn). The irradiation amount (mJ/d) required for curing and the adhesion and water resistance of the cured coating film after complete curing were investigated. The results were as shown in the table below. In addition, adhesion and water resistance were measured by the following method.

Adhesion〉 Make 100 dimples at IR intervals on the cured coating film, and apply pressure-sensitive adhesive tape (trade name NO. manufactured by Nitto Electric Kogyo Co., Ltd.) on top of this.
, 21) was pressed and then the number of remaining pieces when the tape was peeled off was investigated.

<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 was peeled off. ×, if you do
rated it 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 can provide a cured coating film with excellent water resistance. It turns out that there is something.

Claims (1)

[Claims] (1) a) a reaction product of glycidylamine type epoxy 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 ) A photocurable resin composition comprising a photopolymerization initiator.