US4617207A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thermoplastic resin sheet
Assignee: Mitsui Toatsu Chemicals Inc
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Filing: 1984-08-09
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Granted: 1986-10-14
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Expires: 2004-08-09
Abstract
Abstract Disclosed herein are thermoplastic resin sheets having a thermal shrinkage within +/-0.3%, and a process for producing thermoplastic resin sheets by co-extruding a first thermoplastic resin and a second thermoplastic resin which is nonadhesive to the first thermoplastic resin, into a sheet-like structure so that the first thermoplastic resin is covered on both surfaces thereof with the second thermoplastic resin and then peeling off the resulting outer layers of the second thermoplastic resin B to obtain a sheet of the first thermoplastic resin. The thermoplastic resin sheets obtained in accordance with the above production process have an extremely small thermal shrinkage, undergo an extremely low degree of mechanical strain, and exhibits a little optical anisotropy. Because of the small thermal shrinkage, they may be used in liquid crystal displays (LCDs), poultice or sticker. Because of their little optical anisotropy, they may also be used as supports for plate-like polarizers, coating films for plate-like polarizers or optical recording materials.
Inventors
- 👤 Toru Ueki
- 👤 Yoshiaki Fukuda
- 👤 Katsuyuki Usami
- 👤 Kazuharu Kanasaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 09:33
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/18; B; B29; B29C; B29C48/00; B29C48/16; B29C48/18; G; G02; G02B; G02B5/00; G02B5/30; G02B5/3025; G02B5/3033; B29C48/03; B29C48/07; B29C48/08; C09; C09K; C09K2323/00; C09K2323/03; C09K2323/031; Y; Y10; Y10T; Y10T428/00; Y10T428/14; Y10T428/1452; Y10T428/1462; Y10T428/26; Y10T428/31504; Y10T428/31507; Y10T428/31533; Y10T428/31725; Y10T428/31728; Y10T428/31736; Y10T428/31761; Y10T428/31779; Y10T428/31786; Y10T428/3179; Y10T428/31797; Y10T428/31855; Y10T428/3188; Y10T428/31909; Y10T428/31913; Y10T428/31917; Y10T428/3192; Y10T428/31924; Y10T428/31928
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
155 words
Thermoplastic resin sheet having a thermal shrinkage within ±0.3 percent and double refractive index of 8×10 -5 or smaller, said thermoplastic resin sheet being produced by co-extruding a first thermoplastic resin and a second thermoplastic resin which is nonadhesive to said first thermoplastic resin, said first thermoplastic resin being a rigid polyvinyl chloride resin, polystyrene resin or methylpentene resin and said second thermoplastic resin being a low-density polyethylene resin, high-density polyethylene, polyproplylene resin, polystyrene resin or cellulose-base resin, into a three-layered sheet in which a core layer of said first thermoplastic resin is covered on both surfaces thereof with outer layers of the second thermoplastic resin, the proportion of the thickness of said first thermoplastic resin being controlled to below 90 percent of the total thickness of said co-extruded sheet, and by peeling the outer layers of said second thermoplastic resin off said co-extruded three-layered sheet to obtain a sheet of said first thermoplastic resin.
Claim 2
Dependent Claim
155 words
Thermoplastic resin sheet having a thermal shrinkage within ±0.3 percent and double refractive index of 8×10 -5 or smaller, said thermoplastic resin sheet being produced by co-extruding a first thermoplastic resin and a second thermoplastic resin which is nonadhesive to said first thermoplastic resin, said first thermoplastic resin being a rigid polyvinyl chloride resin, polystyrene resin or methylpentene resin and said second thermoplastic resin being a low-density polyethylene resin, high-density polyethylene, polyproplylene resin, polystyrene resin or cellulose-base resin, into a three-layered sheet in which a core layer of said first thermoplastic resin is covered on both surfaces thereof with outer layers of the second thermoplastic resin, the proportion of the thickness of said first thermoplastic resin being controlled to below 90 percent of the total thickness of said co-extruded sheet, and by peeling the outer layers of said second thermoplastic resin off said co-extruded three-layered sheet to obtain a sheet of said first thermoplastic resin.
Claim 3
Dependent Claim
27 words
The plate-like polarizer comprising as its support a thermoplastic resin sheet as claimed in claim 1, which thermoplastic resin sheet has a low level of optical anisotropy.
Claim 4
Dependent Claim
22 words
The plate-like polarizer as claimed in claim 2, wherein the retardation value of the thermoplastic resin sheet is 20 mμ or smaller.
Claim 5
Dependent Claim
22 words
The plate-like polarizer as claimed in claim 2, wherein the thermoplastic resin sheet has been obtained from a polyvinyl chloride resin composition.
Claim 6
Dependent Claim
29 words
The plate-like polarizer as claimed in claim 1 comprising as a coating film a thermoplastic resin sheet as claimed in claim 1 having a low level of optical anisotropy.
Claim 7
Dependent Claim
24 words
The plate-like polarizer as claimed in claim 5, wherein the moisture permeability of the thermoplastic resin sheet is 200 g/m 2 · 24 hrs.
Claim 8
Dependent Claim
22 words
The plate-like polarizer as claimed in claim 5, wherein the retardation value of the thermoplastic resin sheet is 20 mμ or smaller.
Claim 9
Dependent Claim
21 words
A plate-like polarizer as claimed in claim 5, wherein the thermoplastic resin sheet has been obtained from a polyvinyl chloride resin.
Claim 10
Dependent Claim
25 words
The optical recording material comprising a thermoplastic resin sheet as claimed in claim 1, which thermoplastic resin sheet has a low level of optical anisotropy.
Claim 11
Dependent Claim
23 words
The optical recording material as claimed in claim 9 wherein the thermoplastic resin sheet has a retardation value of 100 mμ or smaller.
Claim 12
Dependent Claim
27 words
The optical recording material as claimed in claim 9 wherein the thermoplastic resin sheet has been obtained from a rigid polyvinyl chloride resin, Polycarbonate or methylpentene resin.
Claim 13
Dependent Claim
16 words
The poultice comprising a substrate which is a thermoplastic resin sheet as claimed in claim 1.
Claim 14
Dependent Claim
19 words
The liquid crystal display comprising a film covering which is a thermoplastic resin sheet as claimed in claim 1.
Claim 15
Dependent Claim
57 words
The thermoplastic resin sheet as claimed in claim 1, wherein the first thermoplastic resin is a vinyl chloride resin, polymethacrylate resin, polystyrene resin, acrylonitrile-butadiene-styrene resin, cellulose-base resin, polyethylene resin, polypropylene resin, acetal resin, polyamide resin, polyester resin, polycarbonate resin, polyphenylene oxide resin, polysulfone resin, methylpentene resin, ionomer resin, polyether sulfone resin, polyphenylene sulfide resin or high-nitrile resin.
Claim 16
Dependent Claim
70 words
The thermoplastic resin sheet as claimed in claim 1, wherein the second thermoplastic resin is nonadhesive to the first thermoplastic resin and is selected from a vinyl chloride resin, polymethacrylate resin, polystyrene resin, acrylonitrile-butadiene-styrene resin, cellulose-base resin, low-density or high-density polyethylene resin, polypropylene resin, acetal resin, polyamide resin, polyester resin, polycarbonate resin, polyphenylene oxide resin, polysulfone resin, methylpentene resin, ionomer resin, polyether sulfone resin, polyphenylene sulfide resin or high-nitrile resin.
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) | 1989-10-13 | 1990-04-14 | 1990-10-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-10-13 | 1994-04-14 | 1994-10-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-10-13 | 1998-04-14 | 1998-10-14 | $7700.00 | Window Closed / Lapsed |