Heat-expandable microspheres, method for producing the same, and application thereof
US8324286B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 16, 2006 |
| Grant date | Dec 4, 2012 |
| Priority date | — |
| Expiry date | May 14, 2030 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2984
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Heat-expandable microspheres include a shell of thermoplastic resin and a blowing agent encapsulated therein having a boiling point not higher than the softening point of the thermoplastic resin, have a maximum expanding ratio not lower than 50 times, and are thermally expanded into hollow particulates having a repeated-compression durability not lower than 75 percent. The method of producing the heat-expandable microspheres includes the steps of dispersing an oily mixture containing a polymerizable component and the blowing agent in an aqueous dispersing medium containing a specific water-soluble compound and polymerizing the polymerizable component contained in the oily mixture.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.