Patent US4362895A successfully refreshed from Google Patents.
US4362895A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ultraviolet absorbing copolymers
Assignee: California Institute of Technology
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Filing: 1981-09-21
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Granted: 1982-12-07
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Expires: 2001-09-21
Abstract
Abstract Photostable and weather stable absorping copolymers have been prepared from acrylic esters such as methyl methacrylate containing 0.1 to 5% of an 2-hydroxy-allyl benzophenone, preferably the 4,4' dimethoxy derivative thereof. The pendant benzophenone chromophores protect the acrylic backbone and when photoexcited do not degrade the ester side chain, nor abstract hydrogen from the backbone.
Inventors
- 👤 Amitava Gupta
- 👤 Andre H. Yavrouian
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 13:09
CPC Classifications
C; C08; C08F; C08F212/00; C08F212/02; C08F212/32; C08F220/00; C08F220/02; C08F220/10; C08F220/12; H; H10; H10F; H10F77/00; H10F77/30; H10F77/306; H10F77/311; Y; Y02; Y02E; Y02E10/00; Y02E10/50; Y10; Y10S; Y10S428/00; Y10S428/913; Y10T; Y10T428/00; Y10T428/26; Y10T428/263; Y10T428/31504; Y10T428/31855; Y10T428/31909; Y10T428/31928; Y10T428/31935
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
51 words
A coated article comprising a photolabile substrate containing a coating of an addition polymerized copolymer of a monomer mixture comprising: an acrylic ester of the formula: ##STR3## where R 1 is hydrogen, alkyl of 1 to 6 carbon atoms and R 2 is alkyl of 1 to 6 carbon atoms; and
Claim 2
Dependent Claim
51 words
A coated article comprising a photolabile substrate containing a coating of an addition polymerized copolymer of a monomer mixture comprising: an acrylic ester of the formula: ##STR3## where R 1 is hydrogen, alkyl of 1 to 6 carbon atoms and R 2 is alkyl of 1 to 6 carbon atoms; and
Claim 3
Dependent Claim
88 words
1 to 5% of hydroxy-benzophenone of the formula ##STR4## where R 3 , R 4 , R 5 , R 3' , R 4' , R 5' are individually selected from H, OR 6 or Z where R 6 is methyl, ethyl or propyl and Z is --CH 2 ) m --CH═CH 2 where m is 1 or 2 and at least one but no more than two of R 3 , R 4 , R 5 , R 3' , R 4' or R 5' are Z.
Claim 4
Dependent Claim
88 words
1 to 5% of hydroxy-benzophenone of the formula ##STR4## where R 3 , R 4 , R 5 , R 3' , R 4' , R 5' are individually selected from H, OR 6 or Z where R 6 is methyl, ethyl or propyl and Z is --CH 2 ) m --CH═CH 2 where m is 1 or 2 and at least one but no more than two of R 3 , R 4 , R 5 , R 3' , R 4' or R 5' are Z.
Claim 5
Dependent Claim
19 words
An article according to claim 1 in which the coating has a thickness from 1 mm to 1 cm.
Claim 6
Dependent Claim
15 words
A coated article according to claim 1 in which the substrate is a photovoltaic cell.
Claim 7
Dependent Claim
15 words
A copolymer according to claim 1 in which R 1 and R 2 are methyl.
Claim 8
Dependent Claim
24 words
A copolymer according to claim 1 in which R 3 is Z and at least one of R 4 and R 4' are alkoxy.
Claim 9
Dependent Claim
31 words
A copolymer according to claim 5 in which R 3' , R 5 and R 5' are H, and R 4 and R 4' are both methoxy and m is 1.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-12-06 | 1986-06-07 | 1986-12-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-12-06 | 1990-06-07 | 1990-12-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-12-06 | 1994-06-07 | 1994-12-07 | $7700.00 | Window Closed / Lapsed |