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. 20, 1977
Filed:
Jun. 02, 1975
Simon Babil, Trumbull, CT (US);
James A Claar, Monroeville, PA (US);
Rodger G Temple, Gibsonia, PA (US);
PPG Industries, Inc., Pittsburgh, PA (US);
Abstract
Microcapsules are produced in-situ in a film or during the manufacturing process of a water-based coating composition from which the film is formed. A principal process involves the in-situ production of void-containing microcapsules in a film formed from a water-based coating. This principal process involves as a first step the preparation of a polymer composition which may be a homogeneous solution containing a water-immiscible organic polymer, a water-immiscible solvent for the polymer, and a water-immiscible lower volatility non-solvent which is miscible with the solvent; or an emulsion containing as the continuous phase a water-immiscible organic polymer dissolved in a water-immiscible solvent for the polymer and, as the discontinuous phase, droplets of a lower volatility non-solvent dispersed in the continuous phase. This polymer composition is then emulsified under agitation and in the presence of a surfactant into a water-based coating composition. The water-based coating composition containing this emulsified polymer composition is then applied to a substrate and the solvent is evaporated from the polymer composition to produce microcapsules containing discrete droplets of the non-solvent. Subsequent drying of the water-based coating and evaporation of the non-solvent from the microcapsules produces a film having incorporated therein structured, closed-cell, void-containing microcapsules with the voids serving to provide opacity and gloss control to the film. In an alternative to the principal process, microcapsules containing the non-solvent are produced in-situ in the water-based coating composition prior to forming a film therefrom.