JPH101659A - Adhesive composition for optical disk, cured product, article and adhesion - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition comprising a polyesterpolyurethane (meth)acrylate, an unsaturated group-containing compound and a photopolymerization initiator, and giving cured products excellent in physical properties such as an adhesive property and a recording film-protecting property. SOLUTION: This adhesive composition comprises (A) a polyesterpolyurethane (meth)acrylate obtained by reacting a polyesterdiol with an organic polyisocyanate and a hydroxyl group-containing(meth) acrylate, (B) an unsaturated group-containing compound [e.g. 2-hydroxyethyl (meth)acrylate] except the component A, and (C) a photopolymerization initiator (e.g. 2-hydroxy-2-methyl-1- phenylpropan-1-one). The adhesive composition for optical disks can adhere substrates having the maximum full light transmittance of <=45% in energy light having wavelengths of 280-380nm to each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adhesive composition for an optical disk, and more particularly, to a wavelength of 280 nm or more and 380 nm.
m is 45% or less for energy rays below m
The present invention relates to an adhesive composition for an optical disk which is cured by ultraviolet light capable of adhering substrates as follows, and a cured product thereof.

[0002]

2. Description of the Related Art Conventionally, as a method for bonding opaque substrates, a bonding method using heat has been adopted. Many of the bonding methods using heat are based on epoxy-based, melamine-based, alkyd-based, urethane-based, and acrylic-based resins and a thermosetting agent, and hot-melt-based and the like are also known.

[0003] However, in the bonding method using heat, there is a problem that the substrate is warped or deformed by heat, so that the applicable range of the substrate is limited. Further, the hot melt system has poor thermal stability and weather resistance, and is difficult to use in a high temperature environment. Furthermore, there is a problem that productivity is inferior because the bonding method using heat requires several tens of minutes of curing time. As a result, adhesives on opaque substrates have not yet been provided with satisfactory adhesiveness in productivity.

[0004]

In the above-mentioned conventional heat bonding method, the substrate is warped or deformed, and there is a problem in productivity, and it is desired to solve the problem. In particular, in the case of optical discs that require a higher recording density in the future, there is a need to use an adhesive that is more excellent in adhesiveness, warpage of the disc, protection of the recording film, and deformation. Remains.

[0005]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems. As a result, the present invention can be cured with an opaque substrate, and has an adhesive property, a warp of a disk, and a property of preventing corrosion of a recording film. The present invention has succeeded in providing an adhesive composition, a cured product, an article, and a bonding method for an optical disk which are excellent in deformation and deformation.

That is, the present invention provides (1) a polyester polyurethane (meth) acrylate (A) in which a polyester diol (a) and an organic polyisocyanate (b) are a reaction product of a hydroxyl group-containing (meth) acrylate (c);
(A) an adhesive composition containing an unsaturated group-containing compound (B) other than the component (B) and a photopolymerization initiator (C), in particular, an adhesive composition for a disk; (3) an article having a cured product of the adhesive composition of (1) as an adhesive layer, (4) an article of (3), wherein the article is a DVD, and (5) an article of (1). 28. The adhesive composition
After applying to a substrate having a maximum total transmittance of energy rays of 45% or less at a wavelength of 0 nm to 380 nm, another substrate is brought into close contact with the coated surface, and then irradiated with ultraviolet rays. The method of bonding.

In the present invention, the polyester diol (a)
And organic polyisocyanate (b) and hydroxyl group-containing (meth)
A polyester polyurethane (meth) acrylate (A) which is a reactant of acrylate (c) is used. The polyester polyurethane (meth) acrylate (A) is obtained, for example, by reacting a polyester diol (a) with an organic polyisocyanate (b), and then reacting with a hydroxyl group-containing (meth)
It can be obtained by reacting acrylate (c). Specific examples of the polyester diol (a) include, for example, ethylene glycol, propylene glycol, neopentyl glycol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,9-
Diols such as nonanediol, 1,4-butanediol, diethylene glycol, tripropylene glycol, 1,4-dimethylolbenzene, 1,4-dimethylolcyclohexane, bisphenol A polyethoxydiol and succinic acid, maleic acid, itaconic acid , Phthalic acid,
Isophthalic acid, terephthalic acid, adipic acid, a reaction product of dibasic acids such as dimer acid or acid anhydrides thereof, the diols and ε-caprolactone adduct, the diols and the dibasic acid or These acid anhydrides and ε-
Reaction products with caprolactone and the like can be mentioned. Specific examples of the organic polyisocyanate (b) include, for example, tolylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, diphenylmethane-4,4'-diisocyanate, dicyclopentanyl diisocyanate, hexamethylene diisocyanate,
Examples thereof include 2,4,4'-trimethylhexamethylene diisocyanate and 2,2 ', 4-trimethylhexamethylene diisocyanate.

Specific examples of the hydroxyl group-containing (meth) acrylate (c) include, for example, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 1,4-butanediol mono (meth) acrylate, Reaction product of 2-hydroxyethyl (meth) acrylate and ε-caprolactone, 2-hydroxy-3-
Examples thereof include phenyloxypropyl (meth) acrylate, pentaerythritol tri (meth) acrylate, and glycerin di (meth) acrylate. In the reaction between the polyester diol (a) and the organic polyisocyanate (b), 1.1 to 2.5 equivalents of isocyanate groups of the organic polyisocyanate (b) are reacted with 1 equivalent of the hydroxyl group of the polyester diol (a). It is particularly preferable that the amount is 1.3 to 2.0 equivalents. The reaction temperature is preferably 70 to 100 ° C, and the reaction time is 5
-20 hours are preferred. Next, the reaction product (I) of the polyester diol (a) and the organic polyisocyanate (b) is reacted with the hydroxyl group-containing (meth) acrylate (c). It is preferable to react 0.95 to 1.5 equivalents of the hydroxyl group of the hydroxyl group-containing (meth) acrylate (c) with respect to 1 equivalent of the isocyanate group of the reactant (I),
Particularly preferably, it is 1.0 to 1.1 equivalent. The reaction temperature is preferably from 60 to 100C, and the reaction time is from 5 to 20C.
Time. During the reaction, a polymerization inhibitor (for example, p-methoxyphenol, methylhydroquinone, etc.) to prevent polymerization, and a reaction catalyst (for example,
Di-n-butyltin) can also be used.

[0009] The amount of the polyester polyurethane (meth) acrylate (A) used in the present invention is preferably 5 to 40% by weight, particularly preferably 10 to 30% by weight, in the adhesive composition of the present invention.

In the present invention, an unsaturated group-containing compound (B) other than the component (A) is used. Specific examples of the component (B) include, for example, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate,
1,4-butanediol mono (meth) acrylate, 2
-Ethylhexyl polyethoxy (meth) acrylate,
Benzyl (meth) acrylate, phenyloxyethyl (meth) acrylate, phenyloxyethyloxyethyl (meth) acrylate, tricyclodecane mono (meth) acrylate, isobornyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, dicyclopentenyl Oxyethyl (meth) acrylate,
Acryloyl morpholine, N-vinylcaprolactam,
2-hydroxy-3-phenyloxypropyl (meth)
Acrylate, neopentyl glycol di (meth) acrylate, neopentyl glycol dipropoxy di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, tricyclodegan dimethyl di (meth) acrylate, trimethylolpropane tri (Meth) acrylate monomers such as (meth) acrylate, tris [(meth) acryloxyethyl] isocyanurate and caprolactone-modified tris [(meth) acryloxyethyl] isocyanurate, 2-hydroxyethyl vinyl ether, triethylene glycol divinyl ether Vinyl ether compounds such as cyclohexane-1,4-dimethylol divinyl ether, polyethylene glycol divinyl ether, and epoxy (meth) acrylate {for example, Lumpur A type epoxy resin (e.g., Yuka Shell Epoxy Co., Ltd., Epikote 82
8, epicoat 1001, epicoat 1004, etc.) and epoxy resins such as bisphenol F type epoxy resin and oligomers such as (meth) obtained by reacting with meta (acrylic acid).

The amount of the component (B) used in the present invention is as follows:
In the adhesive composition of the present invention, the content is preferably 59 to 94% by weight, particularly preferably 69 to 89% by weight.

Specific examples of the photopolymerization initiator (C) used in the present invention include, for example, 2-hydroxy-2-methyl-
1-phenylpropan-1-one, hydroxycyclohexylphenyl ketone, methylphenylglyoxylate, benzyldimethyl ketal, Michler's ketone, 2
-Benzyl-2-dimethylamino-1- (4-morpholinophenyl) butanone-1, 2-chlorothioxanthone, 2,4-diethylthioxanthone, 2-isopropylthioxanthone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2,6-Dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide and the like. More preferred initiators include compounds having a maximum molar extinction coefficient of 1000 or more at a wavelength of 360 to 450 nm, for example, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2-chloro. Thioxanthone, 2,4-diethylthioxanthone, 2-isopropylthioxanthone, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide and the like can be mentioned.

In the present invention, a photopolymerization initiator such as an amine can be used in combination. Examples of photopolymerization initiation aids such as amines include 2-dimethylaminoethyl benzoate,
Examples include dimethylaminoacetophenone, ethyl P-dimethylaminobenzoate, and isoamyl P-dimethylaminobenzoate. The amount of the photopolymerization initiator to be used is usually preferably 0 to 15% by weight, more preferably 0 to 15% by weight in the composition.
About 10% by weight.

The amount of the component (C) used in the present invention is as follows:
In the adhesive composition of the present invention, it is preferably 0.5 to 20% by weight, particularly preferably 1 to 15% by weight.

The adhesive composition of the present invention can be prepared by mixing, heating, dissolving and dispersing the components (A) to (C). The cured product of the adhesive composition of the present invention preferably has a refractive index (25 ° C.) of about 1.50 to 1.58. The adhesive composition of the present invention, if necessary, as a polymer, for example, a polyester elastomer, polyacrylic, polyurethane-based, polycarbonate-based resin and the like can be used, and further, if necessary, a silane coupling agent, Polymerization inhibitors, leveling agents, surface lubricants,
Antifoaming agent, light stabilizer, antioxidant, solvating agent, antistatic agent,
Additives such as fillers can also be used in combination.

The cured product of the composition of the present invention can be obtained by irradiating a light beam such as an ultraviolet ray or a visible light laser by a conventional method. The curing of the adhesive composition of the present invention by irradiation of energy rays such as ultraviolet rays is specifically performed by irradiating ultraviolet rays using a low-pressure or high-pressure mercury lamp, a metal halide lamp, a xenon lamp or the like. In particular, 350-4
Lamps with a high energy intensity at 50 nm are preferred.

The composition of the present invention has a wavelength of 280 nm.
The maximum total transmittance at 380 nm or less is about 45
% Or less is useful as an adhesive between opaque substrates. Of course, the case where one is a transparent substrate and the other is an opaque substrate is also applicable. Particularly suitable substrates include substrates for optical disks. The adhesive composition of the present invention is applied on an opaque substrate using a coating apparatus such as a roll coater, a spin coater, or a screen printing method so that a dry coating film thickness is 1 to 50 μm, and ultraviolet rays are applied to the opaque substrate. The substrates can be adhered to each other by irradiating and curing from above the material or from above the transparent substrate. In these methods, the curing of the present composition can be performed by a visible light laser instead of ultraviolet light.

The opaque substrate is an optical disk substrate (for example, polycarbonate resin, amorphous polyolefin resin, etc.) on which an inorganic sputtered film,
In particular, a substrate on which a metal sputtered film is formed, and further, an inorganic sputtered film, particularly a substrate on which an ultraviolet-curable protective film is formed on a metal sputtered film.

[0019]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. The parts in the examples are parts by weight. Examples 1 to 3 and Comparative Examples 1 and 2 An adhesive composition was prepared in accordance with the composition shown in Table 1 and an optical disk substrate (aluminum-deposited polycarbonate substrate at 280 nm to 380 nm An optical disc substrate (gold-sputtered polycarbonate substrate having a maximum total line transmittance of 0.05%) and a gold sputtered film is formed thereon.
The maximum total transmittance at 380 nm or less is 40% or more.
About 10 μm on the gold sputtered film side
m, and was irradiated with ultraviolet rays from the optical disk substrate side of the gold sputtered film to be cured to obtain a test piece. Thereafter, the adhered substrate was peeled off, and the state of the surface was observed. The result of the observation was taken as the curability. In Table 1, ○: no tack was observed. Δ: slight tack was observed.

A peel test was performed using the test pieces obtained above, and the peel value (g / cm) was measured. The results are shown in Table 1.

[0021]

Table 1 Example 1 Comparative Example 1 2 3 12 Aronix M-1200 * 1 30 20 KAYARAD UX-4101 * 2 20 KAYARAD UV-6101 * 3 30 20 KAYARAD R-114 * 4 40 40 40 Aronix M- 315 * 5 20 20 KAYARAD TC-101 * 6 20 20 20 20 KAYARAD R-561 * 7 20 20 20 Acryloylmorpholine 20 20 FA-513A * 8 5 20 20 20 5 Irgacure 1800 * 9 2 22 2 2 Irgacure 184 * 10 55 55 55 Curability ○ ○ ○ ○ ○ Peel value (g / cm) 10 11 11 13

Note) * 1 Aronix M-12
00: Toa Gosei Chemical Co., Ltd., polyester polyurethane acrylate * 2 KAYARAD UX-4101: Nippon Kayaku Co., Ltd., polycaprolactone polyurethane acrylate * 3 KAYARAD UX-6101: Nippon Kayaku Co., Ltd., polyether polyurethane Acrylate * 4 KAYARAD R-114: Nippon Kayaku Co., Ltd., bisphenol A type epoxy acrylate * 5 Aronix M-315: Toa Gosei Chemical Co., Ltd., tris (acryloxyethyl) isocyanurate * 6 KAYARAD TC-101 : Nippon Kayaku Co., Ltd., tetrahydrofurthryl acrylate * 7 KAYARAD R-561: Nippon Kayaku Co., Ltd., phenoxyethyl acrylate * 8 FA-513A: Hitachi Chemical Co., Ltd., tricyclodecane monoacrylate * 9 Irgacure 1800: a mixture of 1-hydroxycyclohexyl phenyl ketone and bis (2,6-dimethoxybenzoyl) 2,4,4-trimethylpentylphosphine oxide, manufactured by Ciba Geigy, photopolymerization initiator * 10 Irgacure 184 : 1-hydroxyclohexyl phenyl ketone, manufactured by Ciba-Geigy, photopolymerization initiator

As is clear from Table 1, the compositions of Examples 1 to 3 are superior in adhesion to the compositions of Comparative Examples 1 and 2.

The adhesive composition for an optical disk of the present invention gives a cured product having excellent properties such as adhesiveness and protection of a recording film.

Claims (6)

[Claims] 1. A polyester polyurethane (meth) acrylate (A) which is a reaction product of a polyester diol (a), an organic polyisocyanate (b) and a hydroxyl group-containing (meth) acrylate (c), and an unsaturated component other than the component (A). An adhesive composition comprising a group-containing compound (B) and a photopolymerization initiator (C). 2. An adhesive composition for an optical disk comprising the above (A), (B) and (C). 3. A cured product of the adhesive composition according to claim 1. 4. An article having a cured product of the adhesive composition according to claim 1 as an adhesive layer. 5. The article is a DVD (digital video disc)
The article of claim 4 which is: 6. The adhesive composition according to claim 1, wherein
After applying to a substrate having a maximum total transmittance of energy rays of 45% or less at a wavelength of 0 nm to 380 nm, another substrate is brought into close contact with the coated surface, and then irradiated with ultraviolet rays. Bonding method.