Process for producing polyurethane foam
US8314029B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 29, 2008 |
| Grant date | Nov 20, 2012 |
| Priority date | — |
| Expiry date | Jun 18, 2029 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08J2375/04
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A method for manufacturing a polishing pad containing substantially spherical cells and having high thickness accuracy includes preparing a cell-dispersed urethane composition by a mechanical foaming method; continuously discharging the cell-dispersed urethane composition from a single discharge port to a substantially central portion in the width direction of a face material A, while feeding the face material A; laminating a face material B on the cell-dispersed urethane composition; then uniformly adjusting the thickness of the cell-dispersed urethane composition by thickness adjusting means; curing the cell-dispersed urethane composition with the thickness adjusted in the preceding step without applying any additional load to the composition so that a polishing sheet including a polyurethane foam is formed; and cutting the polishing sheet.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.