US4654249A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Biaxially drawn, filled polyester film substrates
Assignee: Rhone Poulenc Films SA
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Filing: 1984-07-13
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Granted: 1987-03-31
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Expires: 2004-07-13
Abstract
Abstract Biaxially drawn, filled polyester film substrates, well adapted for the manufacture of magnetic recording tapes, are comprised of a biaxially stretched thermoplastic film matrix including a particulate filler material distributed therethrough, said filler material comprising (a) from about 0.01% to 1% by weight thereof of kaolinite particles having a mean particle size no greater than about 1 micron, and (b) from about 0.01% to 1% by weight thereof of titanium oxide particles also having a mean particle size no greater than about 1 micron.
Inventors
- 👤 Jacques Barbey
- 👤 Marie-Oldile Jacquier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 04:34
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/18; C08K; C08K3/00; C08K3/18; C08K3/20; C08K3/22; C08K3/34; C08K3/346; G; G11; G11B; G11B5/00; G11B5/62; G11B5/73; G11B5/739; G11B5/73923; G11B5/73927; G11B5/73935; C08J2367/00; C08J2367/02; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10S428/91; Y10T; Y10T428/00; Y10T428/24; Y10T428/24479; Y10T428/24612; Y10T428/25; Y10T428/252; Y10T428/256; Y10T428/26; Y10T428/269; Y10T428/31504; Y10T428/31786
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
123 words
A biaxially drawn, filled thermoplastic polyester film substrate, which comprises a biaxially stretched thermoplastic polyester film matrix comprising a particulate filler material distributed therethrough, said filler material comprising (a) from about 0.01% to 1% by weight thereof of kaolinite particles having a mean particle size no greater than about 1 micron, (b) from about 0.01% to 1% by weight thereof of titanium oxide particles also having a mean particle size no greater than about 1 micron, wherein the ratio by weight of said kaolinite particles (a) to said titanium oxide particles (b) ranges from 0.2 to 5, and the total amount of said kaolinite particles (a) and said titanium oxide particles (b) comprise from 0.05% to 1.2% by weight of said thermoplastic polyester.
Claim 2
Dependent Claim
123 words
A biaxially drawn, filled thermoplastic polyester film substrate, which comprises a biaxially stretched thermoplastic polyester film matrix comprising a particulate filler material distributed therethrough, said filler material comprising (a) from about 0.01% to 1% by weight thereof of kaolinite particles having a mean particle size no greater than about 1 micron, (b) from about 0.01% to 1% by weight thereof of titanium oxide particles also having a mean particle size no greater than about 1 micron, wherein the ratio by weight of said kaolinite particles (a) to said titanium oxide particles (b) ranges from 0.2 to 5, and the total amount of said kaolinite particles (a) and said titanium oxide particles (b) comprise from 0.05% to 1.2% by weight of said thermoplastic polyester.
Claim 3
Dependent Claim
42 words
The polyester film substrate as defined by claim 1, said kaolinite particles (a) having a mean particle size no greater than about 0.7 micron and said titanium oxide particles (b) having a mean particle size also no greater than about 0.7 micron.
Claim 4
Dependent Claim
24 words
The polyester film substrate as defined by claim 1, said thermoplastic polyester comprising at least 80% by weight of ethylene glycol terephthalate recurring units.
Claim 5
Dependent Claim
24 words
The polyester film substrate as defined by claim 3, said thermoplastic polyester comprising at least 90% by weight of ethylene glycol terephthalate recurring units.
Claim 6
Dependent Claim
29 words
The polyester film substrate as defined by claim 1, the ratio by weight of said kaolinite particles (a) to said titanium oxide particles (b) ranging from 0.5 to 2.
Claim 7
Dependent Claim
34 words
The polyester film substrate as defined by claim 1, the total amount of said kaolinite particles (a) and said titanium oxide particles (b) comprising from 0.1% to 0.7% by weight of said thermoplastic polyester.
Claim 8
Dependent Claim
28 words
The polyester film substrate as defined by claim 1, biaxially stretched to a draw ratio of from about 3 to 5 in both the longitudinal and transverse directions.
Claim 9
Dependent Claim
23 words
The polyester film substrate as defined by claim 7, having a total surface roughness, R t , ranging from about 0.05 to 0.5.
Claim 10
Dependent Claim
22 words
The polyester film substrate as defined by claim 8 having an average surface roughness, R a , ranging from about 0.005 0.05.
Claim 11
Dependent Claim
24 words
The polyester film substrate as defined by claim 9, having a coefficient of dynamic friction, μ k , ranging from about 0.15 to 0.5.
Claim 12
Dependent Claim
19 words
The polyester film substrate as defined by claim 1, having a thickness ranging from about 1 to 50 microns.
Claim 13
Dependent Claim
14 words
A magnetic recording tape comprising the polyester film substrate as defined by claim 1.
Claim 14
Dependent Claim
17 words
A capacitor comprising as a dielectric layer thereof, the polyester film substrate as defined by claim 1.
Claim 15
Dependent Claim
24 words
The polyester film substrate as defined by claim 9, having a coefficient of dynamic friction, μ k , ranging from about 0.15 to 0.2.
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) | 1990-03-30 | 1990-09-29 | 1991-03-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-03-30 | 1994-09-29 | 1995-03-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-03-30 | 1998-09-29 | 1999-03-31 | $7700.00 | Window Closed / Lapsed |