JPS60228582A - Adhesive for ultraviolet curing plastic - Google Patents

Abstract

PURPOSE:To provide the titled adhesive which can firmly bond plastics without detriment to mechanical characteristics and light transmission, by blending a urethane poly(meth)acrylate, an arom. vinyl monomer and a photopolymerization initiator. CONSTITUTION:10-150pts.wt. arom. vinyl monomer such as styrene and 1- 10pts.wt. photopolymerization initiator such as benzoin methyl ether are blended with 100pts.wt. urethane poly(meth)acrylate contg. at least two (meth)acryloyl groups (e.g. a reaction product of a diisocyanate compd. with 2-hydroxypropyl acrylate). The resulting resin compsn. is useful as an adhesive for acrylic resins such as polymethyl methacrylate.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to adhesives for plastics, and more particularly to adhesives for transparent plastics.

[Prior art]

Plastic materials, especially translucent plastic materials, such as methacrylic resin, styrene resin, vinyl chloride resin, ester resin, nylon resin, carbonate resin, etc., have (1) a lower specific gravity and are lighter than inorganic glass (6Y) (2)
It has the following characteristics: it has excellent impact resistance and is difficult to break; (3) it is easy to process, has a high degree of freedom in shape, is easy to mass produce, and is inexpensive; it is used in lens materials, building materials, lighting equipment, crafts, etc. It is used in a wide range of fields.

Conventional technology for gluing transparent plastic materials
There are (1) a method of adhesion using a solvent, (11) a method of using a thermosetting adhesive, and (iii) a method of using a redonx adhesive. At present, it is extremely difficult to achieve sufficient adhesion of translucent plastic materials, as this may lead to mechanical deterioration, loss of translucency, or deformation of the plastic due to heat. .

[Purpose of the invention]

An object of the present invention is to provide an ultraviolet curable adhesive that can firmly bond plastics without impairing their mechanical properties or translucency.

[Structure of the invention]

The present invention is directed to urethane poly(meth)acrylate having at least two (meth)acryloyl groups in one molecule), an aromatic vinyl monomer 03) and a photoinitiator (C).
This is an ultraviolet curing adhesive for plastics characterized by comprising:

The urethane poly(meth)acrylate having at least two or more (meth)acryloyl groups in one molecule used in the present invention) is a compound having two or more isocyanate groups in the molecule and a (meth)acrylate monomer containing a hydroxyl group. It can be produced by addition reaction with.

Examples of compounds having two or more incyanate groups in the molecule include aliphatic, aromatic or alicyclic polyisocyanates, such as tetramethylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, and dimer isocyanate. , cyclohexane diisocyanate, inphorone diisocyanate, tolylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, m-
Two or more incyanates in the molecule obtained by the reaction of these polyisocyanates such as phenylene diisocyanate and naphthalene diisocyanate with a compound having at least two or more active hydrogen atoms such as an amine group, a hydroxyl group, a carboxyl group, or water. Compounds having groups or trimers to pentamers of the above diisocyanate compounds can be used.

The hydroxyl group-containing (meth)agelylate monomers to be reacted with the isocyanate compound include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl ( Meth)acrylates and monoepoxy7 compounds such as butyl glycidyl ether, 2-ethylhexyl glycidyl ether, addition reaction products of phenyl glycidyl ether and (meth)acrylic acid, and the like.

The polyisocyanate and hydroxyl group-containing (meth)
The addition reaction with acrylate can be carried out using known methods, for example, in the presence of a polyisocyanate compound containing hydroxyl groups (
It can be produced by dropping a mixture of meth)acrylate and a catalyst such as dibutyltin dilaurate at 60 to 90°C. Among the urethane poly(meth)acrylates obtained, urethane diacrylate, which is a reaction product of a diisocyanate compound and 2hydroxyglobyl acrylate, is particularly suitable.

Examples of the aromatic vinyl hexamer-03) which is the second component of the present invention include styrene, vinyltoluene, 0-chlorostyrene, P-chlorostyrene, and mixtures thereof.

Examples of the photoinitiator (C) which is the third component of the present invention include benzoin methyl ether, benzoin ethyl ether, benzoin butyl ether, benzophenone, acetophenone, jetoxyacetophenone, 1,1-dimethoxy-
Usual ones such as 1-phenylacetophenone, benzyl, anthraquinone, 2-ethylanthraquinone, 2-ethylanthraquinone, and 1-chloroanthraquinone can be used without any particular limitation.

In the present invention, °C is urethane poly(meth)acrylate) (
A) Aromatic vinyl monomer (B) per 100 parts by weight
It is preferable to mix 10 to 150 parts by weight of the photoinitiator (C) and 1 to 10 parts by weight of the photoinitiator (C).

Furthermore, the adhesive of the present invention exhibits excellent effects particularly on acrylic resins, especially polymethyl methacrylate.

In the present invention, various monomers, oligomers, resins, additives, etc. can be added to the adhesive of the present invention depending on the purpose and within a range that does not impair the effects of the present invention.

The present invention will be explained in more detail with reference to Examples below. still,
In the examples, "parts" means parts by weight.

Example 1 Production of urethane acrylate (1)> 160 parts of 2-hydroxypropyl acrylate, 1 part of hydroquinone monomethyl ether α, and 0.5 part of dibutyl tin sylate were placed in a three-necked flask, and the mixture was stirred at 60°C to form trimethyl. 100 parts of xamethylene diisocyanate was added dropwise over 6 hours. After the dropwise addition was completed, the reaction was further continued at 60° C. for 15 hours to obtain urethane diacrylate (1).

Production of urethane methacrylate (2)> Urethane dimethacrylate (2) was produced in exactly the same manner as above, except that 130 parts of 2-hydroxyethyl methacrylate was used instead of 2-hydroxyglobyl methacrylate. I got it.

<Production of urethane acrylate (3)> The previous day, in place of trimethylhexamethylene diisocyanate, 172 parts of a trimer of hexamethylene diisocyanate was added to the method for producing urethane diacrylate (1).
Urethane trimethacrylate (4) was obtained in exactly the same manner except that 150 parts of 2-hydroxyethyl methacrylate of hydroxyglopylacrylate was used.

To 100 parts of the urethane poly(meth)acrylate, 60 parts of vinyltoluene, 4 parts of benzoin isobutyl ether
The UV-curable adhesives (1) to (4) were obtained by mixing and dissolving the following parts. Further, 8 parts of a thermoplastic polymer, acryloid B-44 (manufactured by Rohm and Haas), was added to the adhesive (1) to obtain an adhesive (5).

After applying these adhesives to an acrylic resin plate with a thickness of 11111 (manufactured by Mitsubishi Rayon Co., Ltd.), the voltage was 80v/cm.
When cured by irradiating ultraviolet rays for 30 seconds at an irradiation distance of 10α using a high-pressure mercury lamp, the cured films were subjected to a sellotape peel test, and good adhesive strength was obtained in all cases.

Next, an attempt was made to bond acrylic resins together using the adhesive described above.

That is, using acrylic resin with a width of 20 m, a length of 100 m, and a thickness of 1 WR, the bonding area was 200-1400 m2, and then an 80 W/α high-pressure mercury lamp was used to irradiate ultraviolet rays at an irradiation distance of 103 m. It was irradiated for 30 seconds. The thus obtained adhesive-treated methacrylic resin plate was subjected to a 6-point bending test (span width 50 m, cross head heat 2 tm/
min) to determine the peel load. This result is the first
Shown in the table.

Comparative Example 1 Urethane acrylate (1) with adhesive (1) of Example 1
Instead of Epicote +828 (manufactured by Yuka Shell Co., Ltd.)
The adhesive (6) was prepared in the same manner as in Example 1, except that an epoxy acrylate obtained by the addition reaction of 100% with acrylic acid was used, and methyl methacrylate was used instead of vinyltoluene. Glue (7) in the same way
) was obtained.

The adhesives (6) and (7) were adhered under the same conditions as in Example 1, and the peel load was examined. Table 1 shows the results.

Table 1 Example 2 Adhesives (8) to Q4 were experimentally produced by mixing various amounts of vinyltoluene and the photoinitiator jetoxyacetophenone with 100 parts by weight of the urethane diacrylate (1) obtained in Example 1.

The adhesive strength of these adhesives to acrylic resin was investigated using the same method as in Example 1, and the results are shown in Table 2.

Table 2 Example 3 Using the adhesive (1) obtained in Example 1, an attempt was made to adhere a styrene resin sheet, a polycarbonate sheet, and a vinyl chloride resin sheet to each other under the same conditions as in Example 1. When the adhesive-treated plates were subjected to a three-point bending test, it was observed that the base material of each material was destroyed, indicating that good adhesive treatment could be performed.

〔Effect of the invention〕

As detailed above, the adhesive of the present invention can firmly bond plastics without impairing the properties of glasstic, and its effect is remarkable.

Claims (1)

[Claims] 11 molecules are characterized by consisting of at least (urethane poly(meth)acrylate having two or more methane acryloyl groups), an aromatic vinyl monomer (provided), and a photoinitiator (C) Ultraviolet curing adhesive for plastic snacks. 2. The UV-curable adhesive for plastics according to claim 1, wherein the urethane poly(meth)acrylate) is urethane diacrylate which is an addition reaction product of 2-hydroxyglobyl acrylate and a diisocyanate compound. agent. (5) A patent claim characterized in that 10 to 150 parts by weight of aromatic vinyl chloride 03) and 1 to 10 parts by weight of a photoinitiator (C) are contained in 100 parts by weight of urethane poly(meth)acrylate. An ultraviolet curing adhesive for glass as described in Item 1.