EP0484818A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Modification of LCP film by nip rolls
Assignee: CNA Holdings LLC
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Filing: 1991-10-30
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Granted: —
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Expires: 2011-10-30
Abstract
Abstract A method for reducing the anisotropy of an LCP film and producing a film having modified or more balanced properties. The film is calendered by one or more nip rolls in the transverse direction at a temperature sufficient to soften the polymer film so that it will flow under pressure from the rolls, but not so high as to melt the polymer. The nip roll gap and pressure may be set to produce various drawdown ratios. Generally, the greater is the drawdown ratio, the greater is the modification in the film's properties.
Inventors
- 👤 Douglas Duane Dr. Roth
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 21:12
CPC Classifications
B; B29; B29C; B29C55/00; B29C55/02; B29C55/04; B29C55/08; B29C55/18; B29K; B29K2105/00; B29K2105/0079
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
38 words
A process for reducing the anisotropy of an anisotropic polymer film comprising calendering said film, in a direction other than that in which said film is oriented, with a roll having a temperature sufficient to soften said film.
Claim 2
Dependent Claim
43 words
A process according to claim 1 wherein said film is calendered by passing said film between two nip rolls having a gap therebetween that is smaller than the thickness of said film, both said rolls having a temperature sufficient to soften said film.
Claim 3
Dependent Claim
18 words
A process according to claim 2 wherein said calendering direction is approximately perpendicular to said direction of orientation.
Claim 4
Dependent Claim
18 words
A process according to claim 1 wherein said calendering direction is approximately perpendicular to said direction of orientation.
Claim 5
Dependent Claim
31 words
A process according to claim 1 further comprising placing a release film between said polymer film and said roll to prevent adhesion of said polymer film to said roll during calendering.
Claim 6
Dependent Claim
16 words
A process according to claim 1 wherein said temperature is in the approximate range of 150-270°C.
Claim 7
Dependent Claim
74 words
A process for treating a polymer film having an anisotropic molecular orientation comprising the steps of: - heating a pair of nip rolls to a temperature sufficient to soften said film; - adjusting the gap between said rolls to a size less than the thickness of said film; and, - calendering said film by feeding said film through said gap in said rolls in a direction approximately perpendicular to the direction of anisotropic orientation.
Claim 8
Dependent Claim
86 words
A process for treating a polymer film having an anisotropic orientation comprising the steps of: - heating a pair of nip rolls to a temperature sufficient to soften said film; - sandwiching said film between layers of a release film; - adjusting the gap between said rolls to a size less than the thickness of said film sandwich; and, - calendering said polymer film by feeding said film sandwich through said gap in said rolls in a direction approximately perpendicular to the direction of anisotropic orientation.
Claim 9
Dependent Claim
16 words
A process according to claim 8 wherein said temperature is in the approximate range of 150-270°C.
Claim 10
Dependent Claim
17 words
A polymer film obtainable according to a process as claimed in any of claims 1 to 9.
References Cited (Backward Citations)
No citation records indexed.
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