The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 20, 1992
Filed:
Oct. 12, 1990
Do I Lee, Midland, MI (US);
Michael R Mulders, Essexville, MI (US);
Dwayne J Nicholson, Sanford, MI (US);
Arthur N Leadbetter, Midland, MI (US);
The Dow Chemical Company, Midland, MI (US);
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.