Patent US4626304A successfully refreshed from Google Patents.
US4626304A
Expired / Lapsed
US
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Method of making a light-polarizing plate
Assignee: Sumitomo Chemical Co Ltd
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Filing: 1985-09-17
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Granted: 1986-12-02
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Expires: 2005-09-17
Abstract
Abstract A light-polarizing plate for display use is improved in its humid, thermal and weather durabilities by controlling moisture content of a light-polarizing film made of polyvinylalcohol prior to be laminated with protector film and also by using as protector film a hydrophobic polymer film having low water vapor transmission.
Inventors
- 👤 Takuzo Okumura
- 👤 Masataka Yanase
- 👤 Hitoshi Kikui
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 22:59
CPC Classifications
B; B32; B32B; B32B27/00; B32B27/30; B32B27/306; G; G02; G02B; G02B5/00; G02B5/30; B32B27/06; B32B27/08; B32B27/32; G02B5/3025; G02B5/3033; B32B2307/00; B32B2307/40; B32B2307/42; B32B2307/70; B32B2307/728; B32B2323/00; B32B2323/04; B32B2323/043; Y; Y10; Y10S; Y10S428/00; Y10S428/91; Y10S428/913; Y10T; Y10T428/00; Y10T428/23; Y10T428/239; Y10T428/31504; Y10T428/3154; Y10T428/31544; Y10T428/31725; Y10T428/31739; Y10T428/31743
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
71 words
A process for producing a light-polarizing plate comprising a hydrophilic light-producing film covered with high polymer film protector comprising reducing the moisture content of said hydrophilic light-polarizing film to 5% or less then covering the hydrophilic film with a hydrophobic high polymer film protector having a water vapor transmission of not more than 10 g/m 2 day and an average light transmission in the visible region of not less than 30%.
Claim 2
Dependent Claim
71 words
A process for producing a light-polarizing plate comprising a hydrophilic light-producing film covered with high polymer film protector comprising reducing the moisture content of said hydrophilic light-polarizing film to 5% or less then covering the hydrophilic film with a hydrophobic high polymer film protector having a water vapor transmission of not more than 10 g/m 2 day and an average light transmission in the visible region of not less than 30%.
Claim 3
Dependent Claim
16 words
A process according to claim 1 wherein the hydrophobic high polymer film protector is uniaxially stretched.
Claim 4
Dependent Claim
20 words
A process according to claim 1 comprising laminating the hydrophobic high polymer film protector on the hydrophilic light polarizing film.
Claim 5
Dependent Claim
20 words
A process according to claim 1 comprises coating the hydrophobic high polymer film protector on the hydrophilic light polarizing film.
Claim 6
Dependent Claim
24 words
A process according to claim 1 wherein the average light transmission in the visible region of the hydrophobic high polymer is at least 80%.
Claim 7
Dependent Claim
24 words
A process according to claim 5 wherein the average light transmission in the visible region of the hydrophobic high polymer is 80 to 88%.
References Cited (Backward Citations)
US3075857A
Cited
US3244582A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-12-01 | 1990-06-02 | 1990-12-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-12-01 | 1994-06-02 | 1994-12-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-12-01 | 1998-06-02 | 1998-12-02 | $7700.00 | Window Closed / Lapsed |