USH688H
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for surface modification of polyethylene terephthalate film
Assignee: EIDP Inc
•
Filing: 1988-06-16
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Granted: 1989-10-03
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Expires: 2008-06-16
Abstract
Abstract An improved process for surface modification of polyethylene terephthalate film is provided, involving corona discharge treatment of the film in an atmosphere of nitrogen containing up to about 350 ppm oxygen, and optionally a small amount of acetone vapor. Films so treated exhibit improved surface properties.
Inventors
- 👤 Warren S. Sobataka
- 👤 William R. Wolfe, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 23:00
CPC Classifications
C; C08; C08J; C08J7/00; C08J7/12; C08J7/123; B; B29; B29C; B29C59/00; B29C59/10; B29C59/12; B29K; B29K2067/00; C08J2367/00; C08J2367/02
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
132 words
A process for treating a polyester film with a corona discharge in an apparatus comprising at least one electrode and a housing provided with a means for admitting a gas and substantially excluding ambient air, comprising the steps of: (a) providing an atmosphere, within the housing, of nitrogen containing up to about 350 parts per million molecular oxygen; (b) adjusting the energy density of the corona discharge to a value of about 90 to about 140 watts per square inch; (c) continuously passing said film through said housing; and (d) exposing said film, within said housing provided with said nitrogen atmosphere, to said corona discharge, wherein the exposure of said film to said corona discharge is from about 2 to about 64 watt minutes of corona energy per square foot of film.
Claim 2
Dependent Claim
132 words
A process for treating a polyester film with a corona discharge in an apparatus comprising at least one electrode and a housing provided with a means for admitting a gas and substantially excluding ambient air, comprising the steps of: (a) providing an atmosphere, within the housing, of nitrogen containing up to about 350 parts per million molecular oxygen; (b) adjusting the energy density of the corona discharge to a value of about 90 to about 140 watts per square inch; (c) continuously passing said film through said housing; and (d) exposing said film, within said housing provided with said nitrogen atmosphere, to said corona discharge, wherein the exposure of said film to said corona discharge is from about 2 to about 64 watt minutes of corona energy per square foot of film.
Claim 3
Dependent Claim
19 words
The process of claim 1 wherein the atmosphere of nitrogen contains up to about 175 parts per million oxygen.
Claim 4
Dependent Claim
19 words
The process of claim 2 wherein the atmosphere of nitrogen contains up to about 5 parts per million oxygen.
Claim 5
Dependent Claim
26 words
The process of claim 3 wherein the film is exposed to about 3 to about 10 watts minutes of corona discharge per square foot of film.
Claim 6
Dependent Claim
23 words
The process of claim 4 wherein the energy density of the corona discharge is about 100 to about 140 watts per square inch.
Claim 7
Dependent Claim
33 words
The process of claim 5 wherein the width of said film is about 6 feet and the speed of said film through said housing is about 500 to about 1200 feet per minute.
Claim 8
Dependent Claim
11 words
The process of claim 5 wherein the film is polyethylene terephthalate.
Claim 9
Dependent Claim
12 words
The process of claim claim 3 wherein the nitrogen contains acetone vapor.
Claim 10
Dependent Claim
9 words
A film prepared by the process of claim 1.
Claim 11
Dependent Claim
9 words
A film prepared by the process of claim 4.
Claim 12
Dependent Claim
9 words
A film prepared by the process of claim 6.
Claim 13
Dependent Claim
9 words
A film prepared by the process of claim 7.
References Cited (Backward Citations)
US4024038A
Cited
US3853657A
Cited
US4297187A
Cited
FR2544324B1
Cited
US4536271A
Cited
US4594262A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-10-02 | 1993-04-03 | 1993-10-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-10-02 | 1997-04-03 | 1997-10-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-10-02 | 2001-04-03 | 2001-10-03 | $7700.00 | Window Closed / Lapsed |