US4166871A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Iodine stained light polarizer
Assignee: Polaroid Corp
•
Filing: 1978-04-27
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Granted: 1979-09-04
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Expires: 1998-04-27
Abstract
Abstract A visible range light polarizer is prepared by staining an oriented film of polyvinyl alcohol with a solution containing iodine and its red light dichroism is enhanced by treating the stained film with a boric acid solution containing a zinc salt.
Inventors
- 👤 Norman W. Schuler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 23:46
CPC Classifications
G; G02; G02B; G02B5/00; G02B5/30; G02B5/3025; G02B5/3033
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
55 words
A method of preparing a light polarizing element which comprises: uniaxially stretching a film of polyvinyl alcohol; and staining the stretched film with an iodine solution; and treating the stained film with an aqueous solution containing zinc ion in a concentration effective to stabilize absorption of red light by the polarizer against degradation on heating.
Claim 2
Independent Claim
55 words
A method of preparing a light polarizing element which comprises: uniaxially stretching a film of polyvinyl alcohol; and staining the stretched film with an iodine solution; and treating the stained film with an aqueous solution containing zinc ion in a concentration effective to stabilize absorption of red light by the polarizer against degradation on heating.
Claim 3
Dependent Claim
18 words
The method of claim 1 wherein the stained film is treated with an aqueous solution of boric acid.
Claim 4
Dependent Claim
15 words
The method of claim 2 wherein said solution of boric acid additionally contains potassium iodide.
Claim 5
Dependent Claim
14 words
The method of claim 2 wherein said boric acid solution contains said zinc ion.
Claim 6
Dependent Claim
17 words
The method of claim 4 wherein said zinc ion results from dissolving zinc chloride in said solution.
Claim 7
Independent Claim
56 words
A method of preparing a light polarizing element which comprises: uniaxially stretching a film of polyvinyl alcohol; and staining the stretched film with an iodine solution; and treating the stained film with an aqueous borating solution containing zinc ion in a concentration effective to stabilize absorption of red light by the polarizer against degradation on heating.
Claim 8
Independent Claim
56 words
A method of preparing a light polarizing element which comprises: uniaxially stretching a film of polyvinyl alcohol; and staining the stretched film with an iodine solution; and treating the stained film with an aqueous borating solution containing zinc ion in a concentration effective to stabilize absorption of red light by the polarizer against degradation on heating.
Claim 9
Dependent Claim
17 words
The method of claim 6 wherein said aqueous borating solution containing zinc ion additionally contains potassium iodide.
Claim 10
Dependent Claim
13 words
The method of claim 7 wherein said aqueous borating solution comprises boric acid.
Claim 11
Dependent Claim
53 words
In a light polarizing sheet comprising a uniaxially stretched film of polyvinyl alcohol stained with iodine, the improvement wherein said film comprises zinc ion which is absorbed by said film after it is stained with iodine, in a concentration whereby absorption of red light by said polarizer is stabilized against degradation on heating.
Claim 12
Dependent Claim
53 words
In a light polarizing sheet comprising a uniaxially stretched film of polyvinyl alcohol stained with iodine, the improvement wherein said film comprises zinc ion which is absorbed by said film after it is stained with iodine, in a concentration whereby absorption of red light by said polarizer is stabilized against degradation on heating.
Claim 13
Dependent Claim
17 words
The polarizer of claim 9 which additionally comprises a complex of said polyvinyl alcohol and boric acid.
Claim 14
Dependent Claim
10 words
The polarizer of claim 10 which additionally comprises potassium iodide.
Claim 15
Dependent Claim
10 words
The polarizer of claim 9 which additionally comprises potassium iodide.
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) | 1982-09-03 | 1983-03-05 | 1983-09-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-09-03 | 1987-03-05 | 1987-09-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-09-03 | 1991-03-05 | 1991-09-04 | $7700.00 | Window Closed / Lapsed |