초록 ▼

A process for solvent casting acrylic films having superior properties by casting a solution comprising an organic solvent and a polymer system of one or more acrylic polymers onto a carrier, removing the solvent thereby forming the film on the carrier, and stripping the film from the carrier, is di

A process for solvent casting acrylic films having superior properties by casting a solution comprising an organic solvent and a polymer system of one or more acrylic polymers onto a carrier, removing the solvent thereby forming the film on the carrier, and stripping the film from the carrier, is disclosed. The polymer system comprises at least one polymer having the following properties: Total Elongation (%) of about 120-250; Tear Resistance of about 4.5-12.5 g/mil (which is about 177-492 mg/micron); Tensile Strength of about 4500-5000 lbs/in2 (about 317-387 kg/cm2); Molecular Weight (amu) of about 250,000-500,000; Acid Content (%) of about 0.05-5.0; and Tucon hardness (Knoop No.) of about 6-12. The acrylic film has Total Elongation, Tensile Strength, Tear Resistance, Acid Content and Tucon hardness in the aforesaid ranges, and is substantially free of reactive groups, such as hydroxy groups. The residual solvent in the film is (weight %) about 0-3. The film has dimensional stability (% shrinkage at about 130°C. for films of 0.5-5.0 mils, which is about 13-127 microns) of about 0.3. The thickness of the films is generally about 0.5-5.0 mils (which is about 13-127 microns). The films have excellent flexibility and extensibility, are completely free of pinholes, gels and imperfections, and have excellent weatherability.

대표청구항 ▼

A process for producing an acrylic film comprising the steps of: (1) adding an organic solvent to a mixer; (2) adding a polymer system to said organic solvent in said mixer; (3) mixing said solvent and said polymer system to form a mixture that is a true solution of all components; (4) degassing sai

A process for producing an acrylic film comprising the steps of: (1) adding an organic solvent to a mixer; (2) adding a polymer system to said organic solvent in said mixer; (3) mixing said solvent and said polymer system to form a mixture that is a true solution of all components; (4) degassing said mixture to remove all bubbles; (5) casting said degassed mixture on a casting surface; (6) removing said organic solvent from said cast, degassed mixture on said casting surface thereby forming said acrylic film on said casting surface; wherein said acrylic film consists essentially of about 97-100% of said polymer system and about 0-3% of said organic solvent; said polymer system consisting essentially of a polymer or mixture of polymers, each of said polymers consisting essentially of monomers of formula (I): [Figure] wherein R1 is selected from the group consisting of hydrogen and methyl, and R2 is selected from the group consisting of straight or branched alkyl groups of from 1 to 20 carbon atoms, each of said polymers having the following properties: (a) a total elongation of about 120-250%; (b) a tear resistance of about 4.5-12.5 g/mil (177-492 mg/micron); (c) a tensile strength of about 4500-5000 lbs/in2 (about 317-387 kg/cm2); (d) a molecular weight of about 250,000-500,000 amu; (e) an acid content of about 0.0-5.0%; (f) a Tucon hardness in Knoop numbers of about 6-12; (g) being substantially free of reactive groups; said film having each of the aforesaid properties (a) through (c) and (e) through (g), having a thickness of about 0.5-5.0 mils (13-127 microns), having dimensional stability of less than 3.0% shrinkage, being completely free of pinholes and gels.