Polypropylene spunbond fibers and methods for making same
US9212432B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 5, 2008 |
| Grant date | Dec 15, 2015 |
| Priority date | — |
| Expiry date | Oct 21, 2030 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T442/681
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
Disclosed herein is a spunbond fiber of visbroken polypropylene having an Mw/Mn of from 3.5 to 7.0, an Mz/Mw of from greater than 2.0 and a melt flow rate (230/2.16) of from 50 to 100 dg/min. Also disclosed is a process for producing spunbond fibers comprising melt blending a polypropylene having a melt flow rate (230/2.16) of from 10 to 30 dg/min with a peroxide visbreaker such that the resulting melt flow rate of the visbroken polypropylene is from 50 to 100 dg/min; melt extruding the visbroken polypropylene through a die block such that filaments of the visbroken polypropylene being produced are exposed to a cabin pressure of from 4500 to 7000 Pa; and forming fibers of from less than 6.0 denier. Nonwoven fabrics and multiple-layer structures can be made from the fibers described herein that are useful for filtering and absorption related articles.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.