| 摘要 |
<p>Biaxially oriented opaque polypropylene laminated film (I), with a density of 0.4-0.7 g/cm3, has (A) a base layer with a density of 0.35-0.6 g/cm3, which contains vacuoles but no additives of density higher than that of the polypropylene; (B) intermediate layer(s) with no vacuoles; and (C) top layer(s) containing not less than 80 wt.% copolymer of 1.2 to under 2.8 wt.% ethylene and 97.2-98.8 wt.% propylene. Biaxially oriented opaque polypropylene laminated film (I), with a density of 0.4-0.7 g/cm3, has (A) a base layer with a density of 0.35-0.6 g/cm3, which contains vacuoles but no additives of density higher than that of the polypropylene; (B) intermediate layer(s) with no vacuoles; and (C) top layer(s) containing not less than 80 wt.% copolymer of 1.2 to under 2.8 wt.% ethylene and 97.2-98.8 wt.% propylene with melting point 145-160degreesC and melt enthalpy 80-110 J/g. An Independent claim is also included for laminated film (II), which is the same as (I) except that it has a density of 0.45-0.95 g/cm3 and the base layer has a density of 0.4-0.9 g/cm3 and contains titanium dioxide (TiO2).</p> |
