US4087575A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Liquid crystal film
Assignee: Individual
•
Filing: 1976-08-23
•
Granted: 1978-05-02
•
Expires: 1996-08-23
Abstract
Abstract Liquid crystal preparations, for examination of objects by visualizing temperature differences, are made in the form of highly stretchable elastomeric films by dispersing cholesteric liquid crystal esters in a solution of a thermoplastic elastomer such as plasticized polyvinyl butyral solution, and casting a thin film from the solution. Preferably, a light-absorbing lamina is included to enhance the color contrast.
Inventors
- 👤 Kamal F. Bichara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 14:53
CPC Classifications
B; B41; B41M; B41M5/00; B41M5/26; B41M5/28; B41M5/281; C; C09; C09K; C09K19/00; C09K19/52; C09K19/54; C09K19/542; C09K19/544; Y; Y10; Y10S; Y10S428/00; Y10S428/913; Y10T; Y10T428/00; Y10T428/24; Y10T428/24942; Y10T428/2495; Y10T428/24967; Y10T428/26; Y10T428/263; Y10T428/264; Y10T428/269
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
36 words
A color-changing liquid crystal product in self-supporting elastomeric thin film form, comprising cholesteric liquid crystal esters dispersed in direct contact with a matrix of a thermoplastic chemically neutral elastomer in the form of a thin film.
Claim 2
Dependent Claim
36 words
A color-changing liquid crystal product in self-supporting elastomeric thin film form, comprising cholesteric liquid crystal esters dispersed in direct contact with a matrix of a thermoplastic chemically neutral elastomer in the form of a thin film.
Claim 3
Dependent Claim
41 words
A product as in claim 1 in which the elastomer is selected from the class consisting of elastomeric plasticized polyvinyl resins, elastomeric acrylic ester polymers, and elastomeric tri-block polymers with end blocks of a thermoplastic and a central block of elastomer.
Claim 4
Dependent Claim
15 words
A product as in claim 1 in which the elastomer is rubbery plasticized polyvinyl butyral.
Claim 5
Dependent Claim
26 words
A product as in claim 1 in which the film containing the liquid crystal material is laminated to a thin film of black light-absorbing elastomeric material.
Claim 6
Dependent Claim
34 words
A product as in claim 4 in which each film layer consists essentially of elastomeric plasticized polyvinyl butyral, together with, in one layer, cholesteric liquid crystal material, and, in the other layer, black pigment.
Claim 7
Dependent Claim
20 words
A product as in claim 1 in which the elastomeric film has a total thickness not over about 2 mils.
Claim 8
Dependent Claim
20 words
A product as in claim 5 in which the elastomeric film has a total thickness not over about 2 mils.
Claim 9
Dependent Claim
23 words
A product as in claim 1 in which the elastomeric film is in contact with a removable supporting film of essentially inextensible material.
Claim 10
Dependent Claim
23 words
A product as in claim 5 in which the elastomeric film is in contact with a removable supporting film of essentially inextensible material.
Claim 11
Dependent Claim
23 words
A product as in claim 7 in which the elastomeric film is in contact with a removable supporting film of essentially inextensible material.
Claim 12
Dependent Claim
20 words
A product as in claim 10 in which a water-soluble protective film covers the surface opposite to the supporting film.
Claim 13
Dependent Claim
40 words
A process for making a color-changing thin film of elastomeric material, which comprises dissolving a thermoplastic elastomer in a volatile neutral solvent together with cholesteric liquid crystal esters, casting a thin film from the resulting solution, and evaporating the solvent.
Claim 14
Dependent Claim
40 words
A process for making a color-changing thin film of elastomeric material, which comprises dissolving a thermoplastic elastomer in a volatile neutral solvent together with cholesteric liquid crystal esters, casting a thin film from the resulting solution, and evaporating the solvent.
Claim 15
Dependent Claim
26 words
A process as in claim 12, in which the film is cast on an essentially inextensible temporary supporting film of material in soluble in the solvent.
Claim 16
Dependent Claim
27 words
A process as in claim 13, in which the thermoplastic elastomer is polyvinyl butyral together with sufficient plasticizer to make the layer containing the polyvinyl butyral elastomeric.
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) | 1981-05-01 | 1981-10-31 | 1982-05-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-05-01 | 1985-10-31 | 1986-05-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-05-01 | 1989-10-31 | 1990-05-02 | $7700.00 | Window Closed / Lapsed |