Process for making transparent film from vinyl chloride based resins admixed with butadiene-acrylonitrile type copolymers

Claim 1

PROCESS WHICH COMPRISES SUPPLYING (A) A POLYMERIZATION-PRODUCED LATEX OF A COPOLYMER OF (1) A BUTADIENE-TYPE COMPOUND SELECTED FROM THE GROUP CONSISTING OF BUTADIENE, ISOPRENE, 2-METHYL PENTADIENE-1,3, AND MIXTURES OF THESE COMPOUNDS WITH (2) FROM ABOUT 15% TO ABOUT 75%, BASED ON THE WEIGHT OF THE COPOLYMER, OF AN ACRYLONITRILETYPE COMPOUND SELECTED FROM THE GROUP CONSISTING OF ACRYLONITRILE, METHYL ACRYLONITRILE, AND MIXTURES OF THESE COMPOUNDS, SUBSTANTIALLY DEWATERING SAID LATEX WITHOUT THE APPLICATION OF HEAT, DISSOLVING THE COPOLYMER IN AN ORGANIC SOLVENT THEREFOR TO FORM A TRUE SOLUTION THEREOF, INCORPORATING IN SAID SOLVENT, FOR 20 TO 120 PARTS OF THE COPOLYMER, (B) 100 PARTS OF A RESIN SELECTED FROM THE GROUP CONSISTING OF POLYMERS OF VINYL CHLORIDE AND COPOLYMERS THEREOF WITH UP TO 20%, BASED ON THE WEIGHT OF SUCH COPOLYMERS, OF NONCROSS-LINKING UNSATURATED COMPOUNDS COPOLYMERIZABLE THEREWITH, CASTING, UPON A SUPPORT, A FILM FROM THE RESULTING SOLUTION, DRYING SAID FILM, AND STRIPPING SAID FILM FROM SAID SUPPORT.