Method for determining quality of dispersion of glass fibers in a thermoplastic resin preform layer and preform layer characterized thereby
US5436980A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 22, 1992 |
| Grant date | Jul 25, 1995 |
| Priority date | — |
| Expiry date | Dec 22, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/30124
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A method for determining the quality of dispersion of glass fibers in a thermoplastic resin preform layer compares the mean characteristic length of the glass fiber bundles in the preform layer to a predetermined value indicative of dispersion of the glass fibers. The thermoplastic resin preform layer characterized by this method comprises a plurality of individual glass fibers and some degree of undispersed glass fiber bundles intimately mixed with a plurality of discrete thermoplastic fibers. The glass fibers are introduced to the mixture having a length of about 1 cm. to about 8 cm. After mixing, some of the glass fiber bundles break up, and some residual glass fiber bundles remain. A preform layer which has acceptable dispersion has residual glass fiber bundles having a mean apparent length of less about 1.365 mm.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.