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:
Sep. 07, 1976
Filed:
Sep. 19, 1974
Andrejs Baidins, Wilmington, DE (US);
Edward William Gillow, Wilmington, DE (US);
E. I. Du Pont de Nemours and Company, Wilmington, DE (US);
Abstract
The invention relates to a process for preparing vesiculated cross-linked polyester resin granules by polymerizing a water-in-oil-in-water emulsion formed from a polymerizable water-immiscible oil phase, composed of an ethylenically unsaturated monomer and a polyester condensation product and an aqueous phase. The polymerization is effected essentially instantaneously and substantially immediately following the formation of the emulsion by contacting the water-immiscible oil phase at a temperature from 10.degree. to 40.degree.C. with an aqueous phase containing a strong base and having a temperature from 65.degree. to 95.degree.C. Polymerization is thereby effected while the size of the oil phase globules of the water-in-oil emulsion is at a minimum and before appreciable agglomeration can take place, resulting in a reduction in particle size and particle size distribution. The product is especially useful as an opacifying pigment for latex paints and the like, wherein it contributes improved hiding power.