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:
Dec. 14, 1999
Filed:
Aug. 15, 1997
Mark Dwight Clark, Kingsport, TN (US);
Hieu Duy Phan, Kingsport, TN (US);
James Russell Salisbury, Kingsport, TN (US);
Glen Dennis Shields, Kingsport, TN (US);
Eastman Chemical Company, Kingsport, TN (US);
Abstract
This invention provides the preparation of water-dispersible polyester/acrylic hybrids via a two-stage emulsion polymerization process. For example, methacrylic acid and/or 2-hydroxyethyl methacrylate are copolymerized with styrene/acrylic monomers to yield a relatively hydrophilic and hydro-plasticized first stage. Subsequent additions of hydrophobic monomers to this first stage 'seed' results in an inversion of the latex such that the more hydrophilic first stage is at the particle surface. This results not only in improved stability of the resulting latex without the use of additional surfactants, as evidenced by the production of reduced amounts of coagulum, while it also offers relatively low minimum filming temperatures due to the hydroplasticization of the shell of the particle. Furthermore, the use of the water-dispersible polyester results in extremely fine latex particle sizes which can significantly enhance coating properties such as film gloss and clarity.