Patent US5286420A successfully refreshed from Google Patents.
US5286420A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of light polarizing films
Assignee: Bayer AG
•
Filing: 1992-07-14
•
Granted: 1994-02-15
•
Expires: 2012-07-14
Abstract
Abstract A process for the production of light-polarizing films containing polyvinyl alcohol, dichroic dye-producing components, optionally other dye-producing components, optionally additives, and optionally surface active compounds, wherein the films comprise two or more layers and said film layers have a sudden change in composition at the layer phase boundaries between at least two layers, and said layers are applied to a substrate by means of a multiple coater.
Inventors
- 👤 Uwe Claussen
- 👤 Friedrich-Wilhelm Krock
- 👤 Edouard Roche
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 16:06
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/18; B; B29; B29C; B29C39/00; B29C39/02; B29C39/12; B29C39/123; B29C41/00; B29C41/24; B29C41/28; B29C41/32; B29C55/00; B29C55/02; B29C55/023; C08K; C08K5/00; C08K5/0008; C08K5/0041; G; G02; G02B; G02B1/00; G02B1/08; B29K; B29K2029/00; B29K2029/04; B29K2995/00; B29K2995/0018; B29K2995/002; C08J2329/00; C08J2329/02; C08J2329/04
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
75 words
A process for the production of light-polarizing cast films that comprise two or more layers and have a sudden change in their composition at the phase boundary between at least two layers, comprising applying aqueous solutions of polyvinyl alcohol and dichroic dye-producing components to a substrate in two or more layers by means of a multiple coater and drying said layers, after which the dried film is removed from the substrate and is monoaxially stretched.
Claim 2
Dependent Claim
75 words
A process for the production of light-polarizing cast films that comprise two or more layers and have a sudden change in their composition at the phase boundary between at least two layers, comprising applying aqueous solutions of polyvinyl alcohol and dichroic dye-producing components to a substrate in two or more layers by means of a multiple coater and drying said layers, after which the dried film is removed from the substrate and is monoaxially stretched.
Claim 3
Dependent Claim
21 words
A process as claimed in claim 1 in which the layers are applied in wet thicknesses of 10 to 500 μm.
Claim 4
Dependent Claim
28 words
A process as claimed in claim 1 in which the film removed from the substrate is stretched by 300 to 1000% at temperatures of 60° to 180° C.
References Cited (Backward Citations)
US3015989A
Cited
US2996956A
Cited
US3058393A
Cited
US4448823A
Cited
GB2144760A
Cited
US4854995A
Cited
US4960552A
Cited
US4992218A
Cited
US5071906A
Cited
US4941997A
Cited
US5007942A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-02-14 | 1997-08-16 | 1998-02-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-02-14 | 2001-08-16 | 2002-02-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-02-14 | 2005-08-16 | 2006-02-15 | $7700.00 | Window Closed / Lapsed |