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US 5,079,273 AGranted
Dulled stretched molding and process for producing the same
AssigneeChisso Corporation
InventorsTakashi Kuroda, Kazuhiro Yamada, Tadao Ishibashi
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AssigneeChisso Corporation
InventorsTakashi Kuroda, Kazuhiro Yamada, Tadao Ishibashi
Estimating the term…
The disclosed dulled stretched molding of at most 30% in gloss value, which is useful as a general-purpose packaging material, printing paper, tracing paper, etc., is produced from a composition comprising 100 parts by weight of a propylene-ethylene lock copolymer and 3 to 40 parts by weight of a cyclopentadiene type petroleum resin having a ring and ball softening point of at least 160.degree. C. through melt extrusion thereof and stretching of the resulting flat extrudate. There also is disclosed a heat-shrinkable foamed molding of at most 0.85 in density and at least 10% in heat shrinkability at 100.degree. C., which is useful as a packaging material, a tying material, a label material, etc. This heat-shrinkable foamed molding is produced from a composition comprising a crystalline propylene-.alpha.-olefin copolymer having a crystal melting point of at most 150.degree. C. and 5 to 40 wt. %, based on the copolymer, of a hydrogenated cyclopentadiene type resin having a ring and ball softening point of at least 160.degree. C. through melt extrusion thereof and stretching of the resulting flat extrudate.
A dulled stretched molding produced by melt-kneading and melt-extruding a blend composition comprising 100 parts by weight of a propylene-ethylene block copolymer and 3 to 40 parts by weight of a cyclopentadiene type petroleum resin having a ring and ball softening point of at least 160.degree. C. and stretching the resulting flat molding in at least one direction in such a way as to make the resulting stretched molding have a roughened surface of at most 30% in gloss value with a high density of unevenness.
A process for producing a stretched molding, comprising (a) melt-extruding a blend composition comprising 100 parts by weight of a propylene-ethylene block copolymer and 3 to 40 parts by weight of a cyclopentadiene type petroleum resin having a ring and ball softening point of at least 160.degree. C. to form a raw sheet and (b) stretching said raw sheet in at least one direction at a draw ratio of at least 2 at a stretching temperature of at most said ring and ball softening temperature of said cyclopentadiene type petroleum resin.
A heat-shrinkable foamed molding of at most 0.85 in density and at least 10% in heat shrinkability at 100.degree. C., produced by melt-kneading and melt-extruding a blend composition comprising a crystalline propylene-.alpha.-olefin copolymer having a crystal melting point of at most 150.degree. C. and 5 to 40 wt. %, based on said copolymer, of a hydrogenated cyclopentadiene type resin having a ring and ball softening point of at least 160.degree. C. and stretching the resulting extrudate in at least one direction.
A process for producing a heat-shrinkable foamed molding, comprising (a) melt-extruding a blend composition comprising a crystalline propylene-.alpha.-olefin copolymer having a crystal melting point of at most 150.degree. C. and 5 to 40 wt. %, based on said copolymer, of a hydrogenated cyclopentadiene type resin having a ring and ball softening point of at least 160.degree. C. to form a raw sheet and (b) stretching said raw sheet in at least one direction at a draw ratio of at least 3 at a stretching temperature 10.degree. C. or more lower than said crystal melting point of said copolymer.
Dependencies are inferred from the claim text.