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US 5,707,566 AGranted
Process for preparing high performance polarizer films
AssigneeHoechst Celanese Corporation
InventorsSunny S. Shen, Tze-Pei Tien, Hyun Nam Yoon
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Abstract
This invention provides a novel process to prepare high performance polarizing film. In one embodiment, the process includes melt-blending a film-forming wholly aromatic thermotropic liquid crystalline polyester and a dichroic dye and then extruding the blend at a suitable temperature to yield polarizer films with superior polarizing efficiency and thermal and humidity stability.
Claims20
A process to prepare a polarizing film, which film possesses a polarizing efficiency of at least 70%, said process comprising:
- (a) bringing together at least one film-forming, wholly aromatic thermotropic liquid crystalline polyester and one or more dichroic dye into a mix;
- (b) blending said mix at a temperature between 170.degree. C. and the melt temperature of said polymer to make an uniform blend;
- and (c) extruding said blend in a suitable extruder at a temperature between 170.degree. C. and the melt temperature of said polymer to yield the polarizing film, wherein said polyester comprises repeat units corresponding to the formula:
- --P.sup.1 !.sub.m --P.sup.2 !.sub.n --P.sup.3 !.sub.q --P.sup.4 !.sub.r --P.sup.5 !.sub.s --
- wherein P.sup.1, P.sup.2, P.sup.3, P.sup.4 and P.sup.5 represent monomeric moieties, with P.sup.1 being an aromatic hydroxy carboxylic acid, P.sup.2 being an aromatic dicarboxylic acid, P.sup.3 being a phenol, P.sup.4 being a second aromatic hydroxy carboxylic acid moiety different from P.sup.1, and P.sup.5 being a second phenolic moiety different from P.sup.3, and m, n, q, r and s represent mole percent of the respective monomers individually with P.sup.1 and P.sup.2 in the range 5-40 mole percent, P.sup.3 in the range 5-30 mole percent, and P.sup.4 and P.sup.5 in the range 5-20 mole percent.
2 more elements
A process to prepare a polarizing film, which film possesses a polarizing efficiency of at least 70%, said process comprising:
- (a) bringing together at least one film-forming, wholly aromatic thermotropic liquid crystalline polyesteramide and one or more dichroic dye into a mix;
- (b) blending said mix at a temperature between 170.degree. C. and the melt temperature of said polymer to make an uniform blend;
- and (c) extruding said blend in a suitable extruder at a temperature between 170.degree. C. and the melt temperature of said polymer to yield the polarizing film, wherein said polyesteramide comprises repeat units corresponding to the formula:
- --P.sup.1 !.sub.m --P.sup.2 !.sub.n --P.sup.3 !.sub.q --P.sup.4 !.sub.r --P.sup.5 !.sub.s --
- wherein P.sup.1, P.sup.2, P.sup.3, P.sup.4 and P.sup.5 represent monomeric moieties, with P.sup.1 being an aromatic amino carboxylic acid, P.sup.2 being an aromatic dicarboxylic acid, P.sup.3 being a phenol, P.sup.4 being an aromatic hydroxy carboxylic acid, and P.sup.5 being a second phenolic moiety different from P.sup.3, and m, n, q, r and s represent mole percent of the respective monomers individually with P.sup.1 and P.sup.2 in the range 5-40 mole percent, P.sup.3 in the range 5-30 mole percent, and P.sup.4 and P.sup.5 in the range 5-20 mole percent.
2 more elements
A process of preparing a polarizing film which film possesses a polarizing efficiency of at least 70%, said process comprising:
- (a) bringing together at least one film-forming, wholly aromatic thermotropic liquid crystalline polyester and one or more dichroic dye into a mix;
- (b) blending said mix at a temperature between 170.degree. C. and the melt temperature of said polymer to make an uniform blend;
- and (c) molding said blend in a suitable molder at temperatures between 170.degree. C. and the melt temperature of said polymer to yield the polarizing film, wherein said polyester comprises repeat units corresponding to the formula:
- --P.sup.1 !.sub.m --P.sup.2 !.sub.n --P.sup.3 !.sub.q --P.sup.4 !.sub.r --P.sup.5 !.sub.s --
- wherein P.sup.1, P.sup.2, P.sup.3, P.sup.4 and P.sup.5 represent monomeric moieties, with P.sup.1 being an aromatic hydroxy carboxylic acid, P.sup.2 being an aromatic dicarboxylic acid, P.sup.3 being a phenol, P.sup.4 being a second aromatic hydroxy carboxylic acid moiety different from P.sup.1, and P.sup.5 being a second phenolic moiety different from P.sup.3, and m, n, q, r and s represent mole percent of the respective monomers individually with P.sup.1 and P.sup.2 in the range 5-40 mole percent, P.sup.3 in the range 5-30 mole percent, and P.sup.4 and P.sup.5 in the range 5-20 mole percent.
2 more elements
Dependencies are inferred from the claim text.