To provide a releasing polyester film for polarizing plate protection or retardation plate protection, in which the mechanical axis direction and optical axis direction of a film are highly precisely matched with each other and the optical axis direction of the film is uniform in the film surface, to provide the base film of the polyester film, and to provide a method of manufacturing the releasing polyester film for polarizing plate protection or retardation plate protection.
A biaxially-oriented polyester film which is used by being stuck to a polarizing plate or a retardation plate and is used as the base material of the releasing film supplied for an inspection by a Crossed Nicols method is characterized in that: (1) the polyester film has a molecular orientation main axis in the film longitudinal direction and (2) a difference between the refractive index in the film longitudinal direction and refractive index in the film width direction is in the range of ≥0.03 to ≤0.10.
SASAKI YASUSHI
INAGAKI JUN
| JP2002040250A | 2002-02-06 | |||
| JP2003029028A | 2003-01-29 | |||
| JPS61173916A | 1986-08-05 | |||
| JP2007031496A | 2007-02-08 | |||
| JP2005179486A | 2005-07-07 |
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