US3744295A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photochromic-thermochromic coating composition
Assignee: United States Department of the Air Force
•
Filing: 1971-11-24
•
Granted: 1973-07-10
•
Expires: 1991-11-24
Abstract
Abstract A photochromic-thermochromic coating composition is provided that comprises a resin base paint, a dye and an enzyme. The coating composition is sensitive to light and heat, thereby rendering it particularly useful in the non-destructive testing of structures to determine the presence of possible flaws.
Inventors
- 👤 S Allinikov
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 18:54
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/84; G01N21/88; G01N21/91; Y; Y10; Y10S; Y10S252/00; Y10S252/96
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
88 words
The method according to claim 1 in which the paint is a resin base paint; and the enzyme is a member selected from the group consisting of papain, amylase, glucose oxidase, urease and cellulase, the amount of the dye being in the range of about 0.25 to 1.0 part by weight and the amount of the enzyme being in the range of about 0.05 to 0.15 part by weight, both amounts being based on 100 parts by weight of the paint, said dye having the following structural formula:
Claim 2
Dependent Claim
13 words
The method according to claim 1 in which the structure is a laminate.
Claim 3
Dependent Claim
51 words
The method according to claim 2 in which the paint comprises about five to 20 parts by weight of a resin, about 75 to 95 parts by weight of a solvent, and about zero to five parts by weight of a pigment, based on a total of 100 parts by weight.
Claim 4
Dependent Claim
78 words
The method according to claim 4 in which the resin is a member selected from the group consisting of polyvinyl acetate, a copolymer of vinyl chloride and vinyl acetate, polyvinyl chloride, polymethacrylate and a polymer of butyl acrylate; the solvent is a member selected from the group consisting of water, aromatic hydrocarbons, chlorinated hydrocarbons, alcohols, ketones, and esters, and the pigment is a member selected from the group consisting of a titanium dioxide, zinc oxide and calcium carbonate.
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) | 1976-07-09 | 1977-01-08 | 1977-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-09 | 1981-01-08 | 1981-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-09 | 1985-01-08 | 1985-07-10 | $7700.00 | Window Closed / Lapsed |