Abstract: Optical coating compositions containing thin film particulates or pigments that are capable of imparting to the coating preselected optical characteristics or properties, such as selective reflectance, transmission and absorptance of light energy, are comprised of film forming binder and improved high volume pigment particles dispersed in the binder. Each pigment particle is a high volume flake comprised of an inorganic or polymer core having two sides and a thin film optical structure deposited onto each of the two sides of the core. The core occupies a large volume of the coating composition and dramatically reduces the number of flakes and the amount of thin film structures required to produce a coating of given thickness and desired optical properties. The core may also be fabricated to have diffuse and irregular side surfaces in order to render the applied coating visually diffuse and nonspecular. Methods of making the pigment particles are disclosed.

Abstract: A massive article is coated by chemical vapor deposition in a chamber having a horizontal cross-sectional configuration generally matched to the horizontal cross-sectional configuration of the article. For an article which is relatively thin between a pair of opposed faces so that the article is subject to breakage by the force of surging particles of a fluidized particle bed, breakage is reduced in a coating chamber having vertical sidewalls that generally parallel the faces of the article and relatively narrow endwalls. The article is centered in the chamber with its faces parallel to the sidewalls leaving a region between the faces that accommodates an adequate flow of carrier gas and coating vapor without requiring a large charge of particles that would create undue surging force against the article.