| US 7,601,409 B2 | ||
| Stretch film | ||
| Stefan Bertil Ohlsson, Wespelaar (Belgium) | ||
| Assigned to ExxonMobil Chemical Patents Inc., Houston, Tex. (US) | ||
| Filed on Aug. 22, 2003, as Appl. No. 10/646,239. | ||
| Claims priority of provisional application 60/408318, filed on Sep. 05, 2002. | ||
| Prior Publication US 2004/0048019 A1, Mar. 11, 2004 | ||
| Int. Cl. B32B 27/32 (2006.01); B32B 1/08 (2006.01) | ||
| U.S. Cl. 428—35.7 [428/34.1; 428/34.2; 428/35.9; 428/36.92; 428/500; 428/515; 428/521; 428/523; 526/88; 526/160; 526/340.2; 526/348; 526/348.1; 526/348.2; 526/943] | 7 Claims |
| 1. A wrapped article comprising:
an article;
a stretch film;
wherein the stretch film is elongated to the yield plateau and less than the natural draw ratio; and
the article is wrapped with the stretch film, the stretch film comprising:
at least one first layer; and
at least one second layer not comprising a LDPE, wherein any one or more layers comprises a polyethylene copolymer with a
Compositional Distribution Breadth Index (CDBI) of at least 70%, a melt index I2.16 of from 0.1 to 15 g/10 min., a density of from 0.910 to 0.940 g/cm3, a melt index ratio I21.6/I2.16 of from 30 to 80, and an Mw/Mn ratio of from 2.5 to 5.5 and from 0.25 to 6 wt % of one or more tackifiers, wherein:
the film having a natural draw ratio of at least 250%, a tensile stress at the natural draw ratio of at least 22 MPa, and
a tensile stress at second yield point of at least 12 MPa, as measured according to ASTM D-882/97; and
the film having a yield plateau having a linear portion with a slope of at least 0.020 MPa per % elongation interposed between
the second yield point and the natural draw ratio.
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