Slide bead coating method
US6511711B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 21, 2000 |
| Grant date | Jan 28, 2003 |
| Priority date | — |
| Expiry date | Dec 21, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C2001/7411
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A method of bead coating a liquid composition onto the surface of a moving web is taught which provides uniform coatings over a wider range of operating parameters including new coating windows. In addition, the bead coating method typically demonstrates a reduction in coating sensitivity to vacuum pressure noise below the coating bead. The method comprises the steps of forming a bottom layer on a slide surface of a slide bead coating apparatus with a pseudoplastic liquid composition having a viscosity between 8 and 200 centipoises at a shear rate of 100 sec−1 and a viscosity below 10 centipoises at a shear rate of 100,000 sec−1; forming at least one other liquid coating layer above the bottom layer on the slide surface of the slide bead coating apparatus; establishing a coating bead between a lip of the slide bead coating apparatus and the moving web supported on a back-up roller, generating an electrostatic field in an air gap between the coating bead and the moving web just prior to a dynamic wetting line by creating a potential difference across the air gap of between about 300 and about 2000 volts.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.