EP0491504A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Polyester film
Assignee: Zeneca Inc
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Filing: 1991-12-05
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Granted: —
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Expires: 2011-12-05
Abstract
Abstract The invention relates to films of linear polyester containing glass spheres having a certain particle size distribution and in a certain amount. The addition of the glass spheres improves, inter alia, the dynamic coefficient of friction of the film. Preferably, a second film additive, fumed silica, of a controlled particle size distribution and weight is added to the film. The addition of the fumed silica improves, inter alia, the static coefficient of friction of the film.
Inventors
- 👤 Junaid Ahmed Siddiqui
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 19:08
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/18; C08L; C08L67/00; C08K; C08K7/00; C08K7/16; C08K7/18; C08K7/20; C08J2367/00; C08J2367/02
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
72 words
A film of a linear polyester containing glass spheres having an average particle size of about 3 to about 4 microns and a particle distribution of 99.9 percent below about 10 microns, 75 percent below about 6 microns and 50 percent below about 3.8 microns in an amount that ranges between about 30 parts per million to about 150 parts per million based upon the weight of the film of linear polyester.
Claim 2
Dependent Claim
27 words
A film according to claim 1 wherein the weight range of the glass spheres is between about 40 parts per million and about 80 parts per million.
Claim 3
Dependent Claim
71 words
A film according to either one of claims 1 and 2 wherein the film additionally comprises fumed silica having a discrete particle size distribution of 100 percent below 1 micron with the average discrete particle size ranging between about 0.10 to about 0.50 microns in an amount that ranges between about 200 parts per million to about 2000 parts per million based upon the weight of the film of linear polyester.
Claim 4
Dependent Claim
29 words
A film according to claim 3 wherein the average discrete particle size distribution of the fumed silica is in the range between about 0.20 microns to about 0.40 microns.
Claim 5
Dependent Claim
33 words
A film according to either one of claims 3 and 4 wherein the average discrete particle size distribution of the fumed silica is in the range between about 0.25 to about 0.35 microns.
Claim 6
Dependent Claim
39 words
A film according to anyone of claims 3 to 5 wherein the amount of fumed silica that is present in the film ranges between about 600 to about 1000 parts per million based upon the weight of the film.
Claim 7
Dependent Claim
17 words
A film according to anyone of the preceding claims wherein the glass spheres have an etched surface.
Claim 8
Dependent Claim
24 words
A film according to anyone of the preceding claims wherein the film is of a thickness of about 400 gauge to about 500 gauge.
References Cited (Backward Citations)
No citation records indexed.
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