Ultraviolet-curable adhesive composition for bonding opaque substrates

• US 6,284,185 B1
• Filed: 03/09/2000
• Issued: 09/04/2001
• Est. Priority Date: 04/28/1995
• Status: Expired due to Fees

• Current Assignee: Nippon Kayaku Company Limited
• Original Assignee: Nippon Kayaku Company Limited
• Inventors: Tokuda, Kiyohisa, Ishii, Kazuhiko
• Primary Examiner(s): Berman, Susan W.
• Application Number:
  US09/521,547
• Time in Patent Office: 544 Days
• Field of Search: 522/39, 522/42, 522/53, 522/18, 522/64, 522/182, 522/96, 522/103, 428/64.2, 428/65.2, 430/270.11, 430/278.1, 264/494
• US Class Current: 264/494
• CPC Class Codes: C08F 220/281 and containing only one oxygen, e.g. furfuryl (meth)acrylate or 2-methoxyethyl (meth)acrylate
• CPC Class Codes: C08F 220/301 and one oxygen in the alcohol moiety
• CPC Class Codes: C08F 222/102 of dialcohols, e.g. ethylene glycol di(meth)acrylate or 1,4-butanediol dimethacrylate
• CPC Class Codes: C08F 290/067 Polyurethanes; Polyureas
• CPC Class Codes: C08F 290/14 Polymers provided for in subclass C08G
• CPC Class Codes: C09J 4/00 Adhesives based on organic non-macromolecular compounds having at least one polymerisable carbon-to-carbon unsaturated bond ; adhesives, based on monomers of macromolecular compounds of groups C09J183/00 - C09J183/16
• CPC Class Codes: C09J 4/06 Organic non-macromolecular compounds having at least one polymerisable carbon-to-carbon unsaturated bond in combination with a macromolecular compound other than an unsaturated polymer of groups C09J159/00 - C09J187/00
• CPC Class Codes: G11B 7/2533 comprising resins
• CPC Class Codes: G11B 7/2534 polycarbonates [PC]
• CPC Class Codes: G11B 7/256 of layers improving adhesion between layers
• CPC Class Codes: G11B 7/258 of reflective layers
• CPC Class Codes: G11B 7/26 Apparatus or processes specially adapted for the manufacture of record carriers

Abstract

An ultraviolet-curable adhesive composition comprising a photopolymerization initiator whose molar absorption coefficient at a wavelength of 360-450 nm is at least 400 and an ultraviolet-curable compound. The adhesive composition of this invention can bond substrates which show transmittances of 0.01-20% to all of energy beams of a wavelength of 280-380 nm, to one another such as base boards for an optical disk.

Claims

1. A method for preparing an information recording medium comprising coating the ultraviolet-curable adhesive composition on a substrate which is a base board for an optical disk, said base board showing transmittance of 0.01-20% at all wavelengths of energy beams in the region not less than 280 nm but not more than 380 nm, and thereafter firmly contacting the coating surface of this substrate with another substrate, and then irradiating any of said substrate, said another substrate, or both with ultraviolet rays without the use of heat;

said ultraviolet-curable adhesive composition comprising 2,4,6trimethylbenzoldiphenylphosphie oxide as a photopolymerization initiator and an ultraviolet-curable compound which is a resin composed of 20-95 w/w % of a monomer having at least one (meth)acryloyl group in the molecule and 5-80 w/w % of an oligomer having at least two (meth)acryloyl groups in the molecule;

said another substrate shows transmittance of 0.01-20% at all wavelengths of energy beams in the region not less than 280 nm but no more than 380 nm.

2. The method of claim 1, wherein the content of the photopolymerization initiator in the ultraviolet-curable adhesive composition is 0.01-20% byweight.

3. The method of claim 2, wherein said content is 0.5-20% by weight.

4. The method of claim 1, wherein said monomer having at least one (meth)acrylolyl group in the molecule is selected from the group consisting of phenyloxyethyl (meth)acrylate triecyclodecane (meth)acrylate, isobornyl (meth)acrylate, tetrhydrofurfuryl (meth)acrylate, morpholine acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl, (meth)acrylate, neopentylglycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentylglycol hydroxypivalate di(meth)acrylate caprolactone-modified neopentylglycol hydroxypivarate di(meth)acrylate, dipentacrythritol penta(meth)acrylate, dipentacythritol hexa(meth)acrylate, tris((meth)-acryloxyethyl)isocyanurate and carpolactone-modified tris(meth)acryloxyethyl) isocyanurate and said oligomer having at least two (meth)acryloyl groups in the molecule is epoxy (meth)acrylate or urethane (meth)acrylate.

5. The method of claim 1, wherein said information recording medium is a digital video disc.