Patent attributes
Certain embodiments of the present technology provide a capacitor film comprising a polypropylene material. The capacitor film comprises xylene solubles of at least 0.5 percent by weight. In certain embodiments the xylene solubles are in a range of 0.5 to 1.5 percent by weight. The film also comprises a crystalline fraction melting in the temperature range of 200° C. to 105° C. determined by stepwise isothermal segregation technique. The crystalline fraction comprises a part, the part representing at least 10 percent by weight of said crystalline fraction, and wherein the part melts at a melting rate of 10° C./min. Certain embodiments present a capacitor film where the part melts at or below 140° C. In other embodiments, the said part melts at or below the temperature T=Tm−3° C., wherein Tm is the melting temperature of the capacitor film and/or the polypropylene material, and the part represents at least 45 percent by weight of the crystalline fraction.
