Transparent laminate and adhesive film

• US 4,137,364 A
• Filed: 11/05/1976
• Issued: 01/30/1979
• Est. Priority Date: 11/05/1976
• Status: Expired due to Term

• Current Assignee: Monsanto Research Corporation (Bayer AG)
• Original Assignee: Monsanto Research Corporation (Bayer AG)
• Inventors: Salyer, Ival O., Ball, George L. III, Werkmeister, Dennis W.
• Primary Examiner(s): Robinson, Ellis
• Application Number:
  US05/739,367
• Time in Patent Office: 816 Days
• Field of Search: 526/9, 526/11, 526/331, 428/430, 428/429, 428/442, 428/412, 428/520, 428/426, 428/435, 204/159.14, 156/272
• US Class Current: 428/412
• CPC Class Codes: B32B 17/10486 photochromic
• CPC Class Codes: B32B 17/10697 being cross-linked
• CPC Class Codes: B32B 17/10761 containing vinyl acetal
• CPC Class Codes: B32B 17/10788 containing ethylene vinylacetate
• CPC Class Codes: B32B 2305/72 Cured, e.g. vulcanised, cross-linked
• CPC Class Codes: B32B 2307/412 Transparent
• CPC Class Codes: C09J 7/22 Plastics; Metallised plastics
• CPC Class Codes: C09J 7/35 Heat-activated
• CPC Class Codes: Y10T 428/31507 Of polycarbonate
• CPC Class Codes: Y10T 428/31612 As silicone, silane or siloxane
• CPC Class Codes: Y10T 428/31623 Next to polyamide or polyimide
• CPC Class Codes: Y10T 428/31649 Ester, halide or nitrile of addition polymer
• CPC Class Codes: Y10T 428/31928 Ester, halide or nitrile of addition polymer

Abstract

The invention relates to transparent or optically clear laminates and adhesive films used to make these laminates having a temperature utility range far greater than those previously developed and which are especially useful for windshields of high speed aircraft which need such a broad temperature range. These transparent adhesive films have a temperature utility in the range of -65° F to at least 350° F in laminates and comprise an ethylene/vinyl acetate copolymer having a vinyl acetate content in the range of 40% to 60%, the copolymer being partially hydrolyzed to form a terpolymer having a hydroxyl content in the range of 1% to 6%, the terpolymer in film form and/or laminate being heat treated and cross-linked to give the adhesive film. The laminates are made from transparent layers of glass and/or plastic bound together with the transparent adhesive film.

Claims

1. An optically clear adhesive film useful in laminates comprising an ethylene/vinyl acetate/vinyl alcohol terpolymer having a hydroxyl content in the range of 1% to 6%, said terpolymer having been formed by partial hydrolysis of an ethylene/vinyl acetate copolymer having a vinyl acetate content in the range of 40% to 60%, and said terpolymer in film form having been heat treated and crosslinked by means of radiation or curing in the presence of an effective amount of a crosslinking agent selected from the group consisting of vinyl triethoxy silane and isophthaloyl biscaprolactam to give said adhesive film having a temperature utility in laminates in the range of -65°

F. to at least 350°

F.

2. An adhesive film of claim 1 wherein said ethylene/vinyl acetate copolymer has a vinyl acetate content in the range of 45% to 55% and said terpolymer has a hydroxyl content in the range of 2% to 4%.

3. An adhesive of claim 1 wherein said ethylene/vinyl acetate copolymer has a vinyl acetate content of about 50% and said terpolymer has a hydroxyl content of about 3%.

4. An adhesive of claim 1 wherein vinyl triethoxy silane was used as a crosslinking agent.

5. An adhesive of claim 1 wherein isophthaloyl biscaprolactam was used as a crosslinking agent.

6. An adhesive of claim 1 wherein said adhesive film was crosslinked by means of electron bombardment.

7. An adhesive of claim 1 wherein the heat treating was in the range of about 200°

F. to about 400°

F.

8. An optically clear laminate which comprises optically clear layers of glass and/or plastic bound together with an optically clear adhesive film of claim 1.

9. A laminate of claim 8 wherein said layers are glass.

10. A laminate of claim 8 wherein said layers are polycarbonate.

11. A laminate of claim 8 wherein said layers are glass and polycarbonate.

12. A laminate of claim 8 wherein said layers are polycarbonate and acrylic.