Method for preparing solution of cellulose acylate method for producing cellulose acylate film and cellulose acylate film
AssigneeKonica Corporation
InventorsMakoto Honda, Takatoshi Yajima
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Abstract
A method for preparing a solution of cellulose acylate is disclosed. The method comprises comprising the steps of (1) chilling an organic solvent containing no chlorinated organic solvent at a temperature of from −100° C. to −10° C., (2) mixing cellulose acylate containing an alkali-earth metal compound in an amount of from 10 ppm to 100 ppm with said chilled organic solvent to form a mixture, (3) swelling the cellulose acylate in the mixture, and (4) dissolving the mixture containing the swollen cellulose acylate by heating.
Claims20
A method for preparing a solution of cellulose acylate having slight or no turbidity comprising the steps of
- chilling a first organic solvent containing substantially no chlorinated organic solvent at a temperature of from −100° C. to −10° C.,
- mixing cellulose acylate containing an alkali-earth metal compound in an amount of from 10 ppm to 50 ppm with said chilled first organic solvent to form a mixture,
- swelling the cellulose acylate in the mixture, and
- dissolving the mixture containing the swollen cellulose acylate by mixing the mixture containing swollen cellulose acylate with a second organic solvent of temperature of from 0° C. to 120° C. having a composition substantially the same as the first organic solvent.
A method for producing a cellulose acylate film comprising the steps of
- chilling an organic solvent containing no chlorinated organic solvent at a temperature of from −100° C. to −10° C.,
- mixing cellulose acylate containing an alkali-earth metal compound in an amount of from 10 ppm to 50 ppm with said chilled organic solvent to form a mixture,
- swelling the cellulose acylate in the mixture, and
- dissolving the mixture containing the swollen cellulose acylate by heating, and casting the solution to form a film.
A cellulose acylate film produced by the method by casting the solution which is prepared by a method comprising the steps of
- chilling an organic solvent containing no chlorinated organic solvent at a temperature of from −100° C. to −10° C.,
- mixing cellulose acylate containing an alkali-earth metal compound in an mount of from 10 ppm to 50 ppm with said chilled organic solvent to form a mixture,
- swelling the cellulose acylate in the mixture, and
- dissolving the mixture containing the swollen cellulose acylate by heating.
A method for preparing a solution of cellulose acylate comprising the steps of
- mixing cellulose acylate containing an alkali-earth metal compound in an amount of from 10 ppm to 50 ppm with an organic solvent containing no chlorine-containing organic solvent to form a mixture,
- chilling the mixture at a temperature of from −100° C. to −10° C.,
- dissolving the mixture by heating to a temperature of from 0° C. to 50° C.
Dependencies are inferred from the claim text.