Process of making hollow polymer latex particles
US5157084A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 12, 1990 |
| Grant date | Oct 20, 1992 |
| Priority date | — |
| Expiry date | Oct 12, 2010 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S525/902
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
This invention relates to a process of making hollow polymer latex particles without the use of acid in the swellable polymer core; the latexes are useful as opacifying plastic pigments for various coatings and particularly as gloss-enhancing plastic pigments for paper and paperboard coatings. Known methods for preparing hollow latexes require cores containing acid or acidic monomers to enable swelling to core at room temperature. The existence of acid in the polymer disadvantageously increases the polymer's affinity to water. Applicants have discovered that non-carboxylated latexes having a variety of T.sub.g 's will also swell at higher temperatures. The mechanism entails the use of acrylate and methacrylate ester monomers which are hydrolyzable and swellable at higher temperatures in alkaline environments. Such mechanisms for making swollen latexes provide for a wide variety of potential end-uses as well as a wide variety of potential latexes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.