US4427741A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polarizing film
Assignee: Nitto Denko Corp
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Filing: 1981-07-31
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Granted: 1984-01-24
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Expires: 2001-07-31
Abstract
Abstract A polarizing film comprising (a) a polarizer and (b) a film formed on at least one surface of the polarizer from a member selected from the group consisting of thermoplastic polycarbonates, polysulfones, polyethersulfones, polyesters, polyamides and poly(estercarbonate)s' and having a retardation δ of about 500 nm or less with the retardation δ being calculated by the following equation: δ=Δn·d wherein δ is the value at which the polarizing direction of the incident light is directed 45° to the longitudinal axis direction of the film, Δn is a birefringence and d is a thickness of the film in m.
Inventors
- 👤 Kaoru Aizawa
- 👤 Yozo Oishi
- 👤 Tatsuya Kubozono
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 09:11
CPC Classifications
G; G02; G02B; G02B5/00; G02B5/30; G02B5/3083; G02B5/3025; G02B5/3033; C; C09; C09K; C09K2323/00; C09K2323/03; C09K2323/031; Y; Y10; Y10T; Y10T428/00; Y10T428/26; Y10T428/269; Y10T428/31504; Y10T428/31507; Y10T428/31533; Y10T428/31725; Y10T428/31739; Y10T428/31743; Y10T428/31746; Y10T428/3175; Y10T428/31786; Y10T428/31797
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
102 words
A polarizing film comprising (a) a polarizer and (b) a heat-treated film formed on at least one surface of the polarizer from a member selected from the group consisting of thermoplastic polycarbonates, polysulfones, polyethersulfones, polyesters, polyamides and poly(estercarbonate)s' and having a retardation δ of about 500 nm or less with the retardation δ being calculated by the following equation: δ=Δn·d wherein δ is the value at which the polarizing direction of the incident light is directed 45° to the longitudinal axis direction of the film, Δn is the birefringence of the film and d is a thickness of the film in meters.
Claim 2
Dependent Claim
102 words
A polarizing film comprising (a) a polarizer and (b) a heat-treated film formed on at least one surface of the polarizer from a member selected from the group consisting of thermoplastic polycarbonates, polysulfones, polyethersulfones, polyesters, polyamides and poly(estercarbonate)s' and having a retardation δ of about 500 nm or less with the retardation δ being calculated by the following equation: δ=Δn·d wherein δ is the value at which the polarizing direction of the incident light is directed 45° to the longitudinal axis direction of the film, Δn is the birefringence of the film and d is a thickness of the film in meters.
Claim 3
Dependent Claim
14 words
The polarizing film of claim 1, wherein said retardation is 100 nm or less.
Claim 4
Dependent Claim
20 words
The polarizing film of claim 1, wherein said film (b) has a thickness of about 0.01 to about 1.0 mm.
Claim 5
Dependent Claim
26 words
The polarizing film of claim 1, wherein said polarizer is an iodine and/or dichroic dye polarizer, a polyene polarizer or a polyene and dichroic dye polarizer.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-01-23 | 1987-07-25 | 1988-01-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-01-23 | 1991-07-25 | 1992-01-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-01-23 | 1995-07-25 | 1996-01-24 | $7700.00 | Window Closed / Lapsed |