Plastic heating composition including high efficiency heating agents and methods of use
US6423953B1 · kind B1 · utility
Inventor
Key dates
| Filing date | Sep 21, 2000 |
| Grant date | Jul 23, 2002 |
| Priority date | — |
| Expiry date | Sep 21, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T442/2598
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A unique class of high efficiency heating agents consisting of fibers and in particular ferromagnetic fibers for use in alternating magnetic fields is disclosed which have remarkably and unexpectedly high heating efficiencies. The fibers operate efficiently at lower field intensities; at lower frequencies; and, with smaller diameters (related to skin depths) than prior art technologies. The heating agents may be formed from a variety of materials, for example fibers including ferromagnetic material selected from the group consisting of: iron, nickel, cobalt, chromium and alloys thereof; preferably, the fibers can be selected from the group consisting of: carbon steel fibers, magnetic stainless steel fibers, nickel, ferromagnetic coated electrically conductive fibers, ferromagnetic coated electrically nonconductive fibers. The fibers, which are associated with a host material to be heated, are sized, in accordance with skin effect theory, to heat effectively at a frequency which is substantially higher than the actual frequency to be utilized. The fibers have lower apparent density and/or smaller diameters and/or higher surface areas and/or substantially higher heating efficiency th…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.