US4661394A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low glare polycarbonate sheet with improved optical properties
Assignee: General Electric Co
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Filing: 1985-01-30
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Granted: 1987-04-28
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Expires: 2005-01-30
Abstract
Abstract This disclosure describes transparent, low glare, thermoplastic sheet having improved weatherability and reduced distortion levels comprising a textured thermoplastic substrate and a methacrylic coating.
Inventors
- 👤 Herbert L. Curry
- 👤 Ernest E. Roberts
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 12:32
CPC Classifications
B; B29; B29C; B29C59/00; B29C59/02; C; C08; C08J; C08J7/00; C08J7/04; C08J7/0427; C08J7/043; C08J7/06; C08J7/065; C09; C09D; C09D133/00; C09D133/04; C09D133/06; C09D133/10; C09D133/12; C08J2433/00; Y; Y10; Y10S; Y10S428/00; Y10S428/911; Y10T; Y10T428/00; Y10T428/24; Y10T428/24942; Y10T428/31504; Y10T428/31507; Y10T428/31511; Y10T428/31533; Y10T428/31855; Y10T428/31909; Y10T428/31928; Y10T428/31935
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
163 words
A transparent, low glare, thermoplastic composite comprising: (a) a transparent polycarbonate sheet having at least one textured surface with a roughness corresponding to that imprinted by the surface of a 5 to 65 microinch RMS finish roller at a temperature of from about 125° C. to about 145° C.; and, (b) adhered to at least one textured surface of said sheet, a protective coating comprising a methyl methacrylic copolymer consisting essentially of: (i) methyl methacrylate units; (ii) from about 1/2 percent to about 10 percent by number of other methacrylate units selected from the group consisting of ethyl methacrylate, n-butyl methacrylate, i-butyl methacrylate, or mixtures thereof; and (iii) from about 0 percent to about 5 percent by number of other alpha-beta ethylenically unsaturated units; wherein said units are combined in such ratio and polymerized to result in a copolymer material having a tensile elongation at break of greater than about 3.5 percent and a glass transition temperature of greater than about 87° C.
Claim 2
Dependent Claim
163 words
A transparent, low glare, thermoplastic composite comprising: (a) a transparent polycarbonate sheet having at least one textured surface with a roughness corresponding to that imprinted by the surface of a 5 to 65 microinch RMS finish roller at a temperature of from about 125° C. to about 145° C.; and, (b) adhered to at least one textured surface of said sheet, a protective coating comprising a methyl methacrylic copolymer consisting essentially of: (i) methyl methacrylate units; (ii) from about 1/2 percent to about 10 percent by number of other methacrylate units selected from the group consisting of ethyl methacrylate, n-butyl methacrylate, i-butyl methacrylate, or mixtures thereof; and (iii) from about 0 percent to about 5 percent by number of other alpha-beta ethylenically unsaturated units; wherein said units are combined in such ratio and polymerized to result in a copolymer material having a tensile elongation at break of greater than about 3.5 percent and a glass transition temperature of greater than about 87° C.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-04-27 | 1990-10-27 | 1991-04-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-04-27 | 1994-10-27 | 1995-04-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-04-27 | 1998-10-27 | 1999-04-28 | $7700.00 | Window Closed / Lapsed |