Rust preventive film for stretch packaging
US7192652B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Feb 7, 2003 |
| Grant date | Mar 20, 2007 |
| Priority date | — |
| Expiry date | Jun 22, 2023 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31938
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
The stretch film for rustproof stretch packaging has an appropriate roll tack and sufficient self-tack to adhere to and package an object, such as a steel coil. This stretch film has an overall density of 0.870 to 0.935 g/cm3 and is composed of polyolefin resin, rust preventive agents, and an effective amount of a polyolefin polyol adhesive with a number average molecular weight of 500 to 5,000 g/mol. When the film has at least three layers, one surface layer has a density of 0.850 to 0.920 g/cm3, and another surface lever on the opposite side of the film and intermediate layers between them have greater densities. The polyolefin polyol adhesive and the rust preventive agents are present at least in the low density surface layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.