| 摘要 |
A THERMOPLASTIC AND THERMOFORMABLE PIGMENT-CONTAINING METALLIC AUTOMOTIVE PAINT IS SOLVENT CAST AND DRIED TO FORM A FINISHED METALLIC AUTOMOTIVE PAINT COAT FOR A DECORATIVE FILM USED IN A THERMOFORMING PROCESS TO FORM AN EXTERIOR PAINT LAYER ON A MOLDED PLASTIC ANTOMOTIVE BODY PANEL. THE PAINT COAT CONTAINS A PIGMENT UNIFORMLY DISPERSED IN A POLYMERIC BINDER MATERIAL PREFERABLY COMPRISING AN ALLOY OF A POLYVINYLIDENE FLUORIDE (PVDF) COPOLYMER AND AN ACRYLIC RESIN IN WHICH THE PVDF COPOLYMER IS PROVIDED AS A DISPERSION IN THE ACRYLIC RESIN. PREFERABLY, THE DISPERSED FORM OF THE PVDF COPOLYMER HAS A MAXIMUM PARTICLE SIZE LESS THAN ABOUT 35 MICRONS, AND MORE PREFERABLY 20 MICRONS, WITH A MEAN PARTICLE SIZE RANGE OF 6 TO 10 MICRONS. THE DISPERSION RATIO IS PREFERABLY FROM 80TO 2040024108VDF COPOLYMER AND FROM 20TO 80ACRYLIC RESIN, RESPECTIVELY, BY WEIGHT. A LOW MOLECULAR WEIGHT FORM OF THE PVDF COPOLYMER IS PREFERRED AND CHARACTERIZED BY A MELT VISCOSITY OF 17,000 TO 20,000 CENTIPOISE AT 230°C. REFLECTIVE FLAKES ARE UNIFORMLY DISPERSED IN THE POLYMERIC DISPERSION MATERIAL AND THE DISPERSION FORM OF THE PVDF COPOLYMER INHIBITS PARALLEL ORIENTATION OF THE REFLECTIVE FLAKES TO PRODUCE A MORE RANDOM ORIENTATION THAT ACHIEVES A METALLIC APPEARANCE SIMILAR TO STANDARD SPRAY PAINTED METALLIC PAINT COATS. THE CLOSE RESEMBLANCE OF THE METALLIC PAINT COATS IS QUANTIFIED BY SIMILAR TRAVEL INDEX CURVES WHICH INDICATE THE REFLECTANCE OF A SOURCE LAMP AT DIFFERENT VIEWING ANGLES. THE APPEARANCE IS PRODUCED NOT ONLY IN FLEXIBLE DECORATIVE SHEET FORM BUT ALSO WHEN THERMOFORMED TO A THREE-DIMENSIONAL SHAPE WHILE AVOIDING SIGNIFICANT HAZING IN THE THERMOFORMED ARTICLE.
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