Meltblown die tip with capillaries for each counterbore
US6579084B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 25, 2000 |
| Grant date | Jun 17, 2003 |
| Priority date | — |
| Expiry date | Oct 18, 2020 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29L2031/731
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A extruded filament die tip, such as meltblown filaments, has a plurality of bores communicating with the main polymer distribution channel. The bores have a plurality of capillary openings, or spinnerettes, drilled into the bore to act as extrusion orifices for the die tip. The present die tip differs from conventional die tips in which capillaries are drilled into a deep slot formed in the die tip for polymer distribution. The invention allows more material to remain in the body of the die tip while facilitating more spinnerette openings per linear inch in the die tip and permitting higher operating pressures and smaller diameter fibers such as between 1 and 4 microns. A resultant nonwoven fabric made with the die tip will have a higher hydrohead resistance due to the increased number of fine filaments per inch for the same osy of fabric.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.