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AssigneeFuji Photo Film Co., Ltd.
InventorsHidekazu Yamazaki, Toshikazu Nakamura, Hiroshi Miyachi
Estimating the term…
The dope prepared from a mixture solvent and solid contents such as cellulose ester and additives is cast on a drum cooled to −5° C. to form a gel-like film. The gel-like film is peeled off from the drum. Tension of 60 kg/m is applied to the gel-like film in the widthwise direction thereof and the temperature of the gel-like film is kept 120° C., when the content of the solvent to the solid contents in the gel-like film is in a range of 100 wt. % to 20 wt. %. Further the gel-like film is dried to be a cellulose ester film having 40 μm thickness. The IR spectrum of the cellulose ester film has a peak in a range of 520 cm−1 to 480 cm−1 which indicates the crystallization of the polymer. The cellulose ester film has tear strength of 12 g, Rth of 42 nm and Re of 1.2 nm. As crystallization of the polymer proceeds, the cellulose ester film has sufficient strength and optical properties.
A producing method of a cellulose ester film comprising the steps of:
A producing method of a cellulose ester film comprising the steps of:
A producing method of a cellulose ester film, an infrared absorption spectrum of said cellulose ester film having a peak in a range of 520 cm−1 to 480 cm−3, a tear strength being at least 6 g, and retardation in thickness direction (Rth) being at least 35 nm, said producing method comprising the steps of:
A producing method of a cellulose ester film, said cellulose ester film being produced by casting a dope containing a solvent and solid contents such as cellulose ester to form a gel-like film and by drying said gel-like film with applying tension on it, said producing method comprising:
Dependencies are inferred from the claim text.