Claims
- 1. A solid photocurable film adhesive comprising:
- (I) a photocurable material having, on average, more than one acrylic group per molecule consisting essentially of a mixture of (a)(i) a urethane acrylate having, on average, more than one acrylic group per molecule which is a reaction product of an isocyanate-terminated polyurethane prepolymer with a hydroxyl group-containing acrylic compound or (II) a polyester acrylate having, on average, more than one acrylic group per molecule which is a polyester modified after formation by reaction to introduce, on average, more than one acrylic group per molecule or (III) said urethane acrylate and said polyester acrylate with (b) a polyacrylic ester of an epoxide resin, at least 20% of said photocurable material being component (a),
- (II) as sole or major solid film-forming component, a solid polyvinylacetal present in an amount from 20 to 150% by weight of the photocurable material (I), and
- (III) a photoinitiator for photopolymerisation of acrylic compounds.
- 2. A film adhesive according to claim 1, in which the urethane acrylate is an aliphatic or cycloaliphatic urethane acrylate.
- 3. A film adhesive according to claim 1, in which the prepolymer is a reaction product of a polyol with a stoichiometric excess of an aliphatic or cycloaliphatic diisocyanate.
- 4. A film adhesive according to claim 1, in which the hydroxyl-containing acrylic compound is a hydroxyalkyl acrylate or a hydroxyalkyl methacrylate.
- 5. A film adhesive according to claim 1, in which (a) is a polyester acrylate or a mixture thereof with a urethane acrylate.
- 6. A film adhesive according to claim 5, in which the polyester acrylate is a reaction product of a hydroxyl-terminated polyester with an acrylic compound having a hydroxyl-reactive group which is a carboxylic group, a carboxylic acid halide group or an epoxide group.
- 7. A film adhesive according to claim 5, in which the polyester acrylate is a reaction product of a carboxyl-terminated polyester with an acrylic compound having a hydroxyl group or an epoxide group.
- 8. A film adhesive according to claim 5, in which component (I) comprises substantially all of the photocurable content of the adhesive.
- 9. A film adhesive according to claim 5, in which the polyester acrylate is a polyester modified after formation by reaction to introduce, on average, more than one acrylic group per molecule.
- 10. A film adhesive according to claim 1, in which the polyacrylic ester of an epoxide resin is a diacrylic ester of an advanced diglycidyl ether of bisphenol A.
- 11. A film adhesive according to claim 10, in which the polyvinylacetal (II) is a polyvinylbutyral.
- 12. A film adhesive according to claim 1, in which the polyvinylacetal (II) is a polyvinylbutyral.
- 13. A film adhesive according to claim 12, in which the polyvinylbutyral has a softening point of at least 150.degree. C.
- 14. A film adhesive according to claim 12, in which the polyvinylbutyral has a softening point of at least 200.degree. C.
- 15. A film adhesive according to claim 1, in which the photoinitiator (III) is an alpha-substituted acetophenone, a thioxanthone, a benzophenone or a mixture of two or more thereof.
- 16. A film adhesive according to claim 1, which also contains a liquid photopolymerizable monovinyl monomer as reactive diluent.
- 17. A film adhesive according to claim 1, which also contains an elastomeric polymer as toughening agent.
- 18. A film adhesive according to claim 17, in which the elastomeric polymer is a vinyl-terminated butadiene-acrylonitrile copolymer.
- 19. A film adhesive according to claim 1 in solution in a volatile solvent.
- 20. A film adhesive according to claim 1, in which component (a) is a reaction product of an isocyanate-terminated polyurethane prepolymer with a hydroxyl group-containing acrylic compound or a polyester modified after formation by reaction to introduce, on average, more than one acrylic group per molecule, component (b) is a diacrylic ester of an advanced diglycidyl ether of bisphenol A and component (II) is a polyvinyl butyral.
- 21. A film adhesive according to claim 1, in which component (I) comprises substantially all of the photocurable content of the adhesive.
- 22. A film adhesive according to claim 1 consisting essentially of components (I), (II) and (III).
- 23. A data-carrying laminate comprising (A) a data-carrying sheet of paper or thermoplastic polymeric material bonded to (B) a transparent protective plastics sheet by a film adhesive according to claim 1 photocured between, and in contact with, (A) and (B).
- 24. A laminate according to claim 23, in which (A) is a polyester film and (B) is of a polyester or a polyvinyl chloride.
Priority Claims (1)
Number |
Date |
Country |
Kind |
9110783 |
May 1991 |
GBX |
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Parent Case Info
This application is a continuation of application Ser. No. 07/881,574, filed May 12, 1992, now abandoned.
US Referenced Citations (6)
Foreign Referenced Citations (5)
Number |
Date |
Country |
1267478 |
Apr 1990 |
CAX |
0273012 |
Jun 1988 |
EPX |
0348349 |
Dec 1989 |
EPX |
0375609 |
Jun 1990 |
EPX |
0423713 |
Apr 1991 |
EPX |
Non-Patent Literature Citations (7)
Entry |
Derwent Abstract of DE2607955-A, AN: 77-63257Y/36 Sep., 1977. |
Derwent Abst. 87-133662/19 (1987). |
Derwent Abst. 86-322303/49 (1986). |
Derwent Abst. 38080 E/19 (1982). |
Derwent Abst 91-152485/21 (1991). |
Derwent Abst. 88-294864/42 (1988). |
Derwent Abst. 90-362946/49 (1990). |
Continuations (1)
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Number |
Date |
Country |
Parent |
881574 |
May 1992 |
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