초록 ▼

The invention is directed to a method and apparatus for coating substrates by a liquid spray so as to avoid entrapment of gaseous bubbles, particularly air bubbles, in the coating and desirably to thereby obtain bubble-free coatings. More particularly, the invention involves spray applying the coati

The invention is directed to a method and apparatus for coating substrates by a liquid spray so as to avoid entrapment of gaseous bubbles, particularly air bubbles, in the coating and desirably to thereby obtain bubble-free coatings. More particularly, the invention involves spray applying the coating to a substrate in an atmosphere consisting of gases having appreciable solubility in the applied coating, such as carbon dioxide, such that gas bubbles that may become entrapped in the coating are removed after application by the gases dissolving into the coating and diffusing to the surface.

대표청구항 ▼

[ What is claimed is:] [1.] A method for liquid spray application of coatings onto a substrate which minimizes entrapped non-soluble gaseous bubbles comprising:a) forming a liquid coating composition containing at least one polymeric compound capable of forming a coating on a substrate;b) spraying,

[ What is claimed is:] [1.] A method for liquid spray application of coatings onto a substrate which minimizes entrapped non-soluble gaseous bubbles comprising:a) forming a liquid coating composition containing at least one polymeric compound capable of forming a coating on a substrate;b) spraying, without a viscosity-reducing diluent under supercritical conditions, into an environment of non-soluble gas or gases, said liquid coating composition toward asubstrate;c) providing one or more gases which are soluble in said polymeric coating composition so as to create a first atmosphere encompassing the sprayed liquid coating composition, wherein said soluble gases are provided under conditions which cause the sprayed liquid to be applied to the substrate in said first atmosphere that contains the one or more soluble gases in a sufficiently high portion to alleviate entrapped non-soluble gases in the coating;d) coating the substrate; ande) subjecting the coated substrate to a second atmosphere in which said one or more soluble gases are in lower concentration than in the first atmosphere so that the one or more soluble gases diffeuse from the coated substrate into said second atmosphere.