Anti-corrosive material
US6224957A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 24, 1996 |
| Grant date | May 1, 2001 |
| Priority date | — |
| Expiry date | Jun 24, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31913
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
An improved anti-corrosive material used to protect buried conduits from corrosion. The material is a multi-layered co-extruded, calendered, or laminated polyolefin. The material has an outer layer, or environment contacting layer, preferably comprised of a low density polyethylene having characteristically strong tensile strength and elongation properties to provide conventional protection from soil, water, air, or other potentially damaging elements. The material has a center layer preferably comprised of a high density polyethylene having superior tensile strength to provide a high density barrier between the outer layer and an inner layer. The inner layer, or conduit contacting layer, is preferably comprised of a low density polyethylene impregnated with a biocide, a volatile corrosion inhibitor (VCI), or both. The biocide and VCI are able to migrate through the low density polymer matrix but the rate of migration of the biocide is considerably slowed through the high density polymer and the VCI is essentially unable to penetrate it. Thus, the biocide and VCI are substantially prevented from escaping into the surrounding environment, but rather, are trapped within a "protection…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.