Nonwoven fabrics and method for producing them
US4818587A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 15, 1987 |
| Grant date | Apr 4, 1989 |
| Priority date | — |
| Expiry date | Oct 15, 2007 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T442/641
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
Nonwoven fabrics contain at least 30% by weight of heat-adhesive composite fibers consisting of core portion and sheath portion, said core portion being of the side-by-side type composite structure comprising two core components of different polypropylene base polymers in a composite ratio of 1:2 to 2:1, one of said core components having a Q value, expressed in terms of the weight-average molecular weight/the number-average molecular weight, equal to or higher than 6 and the other having a Q value equal to or lower than 5, and said sheath portion meeting at least the requirement that it should comprise a sheath component of a polyethylene base polymer having a melting point lower by at least 20.degree. C. than the lower one of the melting points of said two core components. The nonwoven fabrics are bulky and soft due to the crimps of the heat-adhesive composite fibers resultant from the core portion and are stabilized by the inter-fiber bonds of the sheath portion.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.