GB2087302A
Expired / Lapsed
GB
⏱️ 0.0 years remaining
Polyester films
Assignee: Teijin Ltd
•
Filing: 1981-10-14
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Granted: —
•
Expires: 2001-10-14
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
GB
Data Source
google_patents
Last Synchronized
2026-10-23 02:15
CPC Classifications
B; B29; B29C; B29C55/00; B29C55/02; B29C55/10; B29C55/12; B29C55/14; G; G11; G11B; G11B5/00; G11B5/62; G11B5/73; G11B5/739; G11B5/73923; G11B5/73927; G11B5/73929; G11B5/73935; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10S428/91; Y10T; Y10T428/00; Y10T428/24; Y10T428/24355; Y10T428/24372; Y10T428/24405; Y10T428/24479; Y10T428/25; Y10T428/259; Y10T428/31504; Y10T428/31786
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
28 words
A polyester film characterized by having many uneven units on its surface, each of said uneven units being composed of a fine projection and a depression existing therearound.
Claim 2
Dependent Claim
28 words
A polyester film characterized by having many uneven units on its surface, each of said uneven units being composed of a fine projection and a depression existing therearound.
Claim 3
Dependent Claim
27 words
A polyester film according to claim 1 wherein each depression has an elliptical shape with along 5 diameter in the range of 2 [im to 50 ptm.
Claim 4
Dependent Claim
66 words
A polyester film according to claim 1 or 2 wherein the following reaction exists between the frequency of occurrence of the uneven units N (per mm') and the long diameter D ([tm) of the depression, when 2 <D<5,200 -- N<3500, when 5 --< D<10, 150 -- N<2000, when 10 --< D<30, 50 -N <800, and when 30 -- D -- 50, 0 -- N -- 5.
Claim 5
Dependent Claim
55 words
A polyester film according to claim 1, 2 or 3 wherein each uneven unit consists of a projection formed owing to an inert additive and/or a catalyst residue contained in the polyester and a depression around it, said depression being of an elliptical shape having a long diameter along the stretching direction of the film.
Claim 6
Dependent Claim
20 words
A polyester film according to claim 1 substantially as described by reference to Figures 2-1 and 2-2 of the drawings.
Claim 7
Dependent Claim
15 words
A polyester film according to claim 1 substantially as describe in anyone of the Examples.
Claim 8
Dependent Claim
114 words
A process for producing a polyester film as claimed in anyone of the preceding claims, which process comprises preheating an unstretched polyesterfilm containing internal particles attributed to an inert additive having an average particle diameter of 0.05 to 5 Itm and/or a catalyst residue to a temperature of 80 to 120OC; stretching the film in a first axial direction to 2.6 to 3.5 times at a temperature of 110 to 145OC; thereafter, stretching the film in a second axial direction at right angles to the first axial direction to 3.0 to 4.0 times at a temperature of 100 to 150'C; and then heat- setting the stretched film at a temperature of 160 to 2400C.
Claim 9
Dependent Claim
49 words
A process according to claim 7 substantially as described with reference to anyone of the Examples. Printed for Her Majesty's Stationery Office, by Croydon Printing Company Limited, Croydon, Surrey, 1982. Published by The Patent Office, 25 Southampton Buildings, London, WC2A lAY, from which copies may be obtained. i. ii,
References Cited (Backward Citations)
No citation records indexed.
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