Patent US5466531A successfully refreshed from Google Patents.
US5466531A
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US
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Polytetrafluoroethylene laminate and method of producing same
Assignee: Textiles Coated International
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Filing: 1994-08-03
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Granted: 1995-11-14
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Expires: 2014-08-03
Abstract
Abstract A flexible fluoroplastic laminate comprising a plurality of unsintered oriented PTFE films laminated under conditions of elevated temperature and pressure. At least one of the films has its direction of orientation disposed angularly with respect to that of at least one other of the films. The films retain their orientation following lamination.
Inventors
- 👤 Stephen W. Tippett
- 👤 Robert C. Ribbans
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:15
CPC Classifications
B; B32; B32B; B32B7/00; B32B7/03; B32B7/04; B29; B29C; B29C65/00; B29C65/02; B29C65/18; B29C66/00; B29C66/01; B29C66/05; B29C66/10; B29C66/11; B29C66/112; B29C66/1122; B29C66/40; B29C66/41; B29C66/45; B29C66/70; B29C66/71; B29C66/72; B29C66/723; B29C66/7234; B29C70/00; B29C70/04; B32B27/00; B32B27/06; B32B27/08; B32B27/32; B32B27/322; B32B37/00; B32B37/10; B32B37/14; B32B37/144; B32B7/12; C; C08; C08J; C08J5/00; C08J5/12; C08J5/121; B29K; B29K2027/00; B29K2027/12; B29K2027/18; B29K2995/00; B29K2995/0037; B29K2995/005; B29K2995/0051; B29L; B29L2009/00; B32B2305/00; B32B2305/80; B32B2307/00; B32B2307/50; B32B2307/514; B32B2307/516; B32B2309/00; B32B2309/02; B32B2309/022; B32B2309/025; B32B2327/00; B32B2327/12; B32B2327/18; C08J2327/00; C08J2327/02; C08J2327/12; C08J2327/18; Y; Y10; Y10S; Y10S277/00; Y10S277/935; Y10S277/944; Y10S277/945; Y10S277/946; Y10S428/00; Y10S428/91; Y10T; Y10T428/00; Y10T428/24; Y10T428/24058; Y10T428/31504; Y10T428/3154; Y10T428/31544
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
90 words
A flexible fluoroplastic chemical barrier laminate having improved toughness, said laminate comprising a plurality of axially oriented unsintered polytetrafiuoroethylene films laminated directly together without entrapped air or the interposition of an adhesive therebetween at a temperature above the melt temperature of said films but below 900° F., said films being sintered during lamination and remaining axially oriented following lamination, with at least one of said films having its direction of orientation disposed angularly with respect to that of at least one other of said films adjacent to said one film.
Claim 2
Dependent Claim
90 words
A flexible fluoroplastic chemical barrier laminate having improved toughness, said laminate comprising a plurality of axially oriented unsintered polytetrafiuoroethylene films laminated directly together without entrapped air or the interposition of an adhesive therebetween at a temperature above the melt temperature of said films but below 900° F., said films being sintered during lamination and remaining axially oriented following lamination, with at least one of said films having its direction of orientation disposed angularly with respect to that of at least one other of said films adjacent to said one film.
Claim 3
Dependent Claim
18 words
The laminate of claim 1 wherein said films are laminated at a pressure of 1 to 60 p.s.i.
Claim 4
Dependent Claim
19 words
The laminate of claim 2 wherein said films are laminated for a time period of 20 to 70 seconds.
Claim 5
Dependent Claim
21 words
The laminate of claims 1, 2 or 3 wherein said films are laminated at a temperature of 660° to 760° F.
Claim 6
Dependent Claim
20 words
The laminate of claim 1 wherein said films are uniaxially oriented and range in thickness from 1 to 10 mils.
Claim 7
Dependent Claim
24 words
The laminate of claim 1 wherein the molecules of adjacent films are commingled to form interphase zones at the bond lines between said films.
Claim 8
Independent Claim
109 words
A method of producing a flexible fluoroplastic chemical barrier laminate having improved toughness, said method comprising: a.) stacking a plurality of axially oriented unsintered polytetrafiuoroethylene films without interposing an adhesive therebetween, with at least one of said films having its direction of orientation disposed angularly with respect to that of at least one other of said films adjacent to said one film; and b.) confining the stacked films between heated platens to expel entrapped air from between said films while laminating said films at a temperature above the melt temperature of said films but below 900° F., said films being sintered during lamination and remaining axially oriented following lamination.
Claim 9
Independent Claim
109 words
A method of producing a flexible fluoroplastic chemical barrier laminate having improved toughness, said method comprising: a.) stacking a plurality of axially oriented unsintered polytetrafiuoroethylene films without interposing an adhesive therebetween, with at least one of said films having its direction of orientation disposed angularly with respect to that of at least one other of said films adjacent to said one film; and b.) confining the stacked films between heated platens to expel entrapped air from between said films while laminating said films at a temperature above the melt temperature of said films but below 900° F., said films being sintered during lamination and remaining axially oriented following lamination.
Claim 10
Dependent Claim
23 words
The method of claim 7 wherein lamination is effected by heating said films to a temperature of between about 660° and 760° F.
Claim 11
Dependent Claim
21 words
The method of claim 7 wherein lamination is effected while subjecting said films to a pressure of 1 to 60 p.s.i.
Claim 12
Dependent Claim
20 words
The method of claim 7 wherein lamination is effected for a time period of between about 20 to 70 seconds.
Claim 13
Dependent Claim
24 words
The method of claim 7 wherein the molecules of adjacent films commingle to create molecular interphase zones at the bond lines between said films.
Claim 14
Dependent Claim
20 words
The method of claim 7 wherein prior to lamination, at least some of said films are integrally combined into sublaminates.
Claim 15
Dependent Claim
57 words
The method of claim 12 wherein said sublaminates are formed by pressing said films together under conditions of elevated pressure and temperature for a time interval sufficient to effect adhesion at the interface between adjacent films, said adhesion being such that the films of the sublaminate may be readily delaminated without distorting, stretching or degrading said films.
Claim 16
Dependent Claim
21 words
The method of claim 13 wherein said sublaminates are formed by subjecting said films to a pressure of about 40 p.s.i.
Claim 17
Dependent Claim
24 words
The method of claim 13 wherein said sublaminates are formed by heating said films to a temperature of between about 250° and 300° F.
Claim 18
Dependent Claim
31 words
The method of claim 13 wherein said sublaminates are formed by subjecting said films to conditions of elevated pressure and temperature for a time period of about 15 to 25 seconds.
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