COATING HIGH SOLIDS FILM-FORMING COMPOSITIONS

摘要

Coating high solids film-forming compositions High solids coating methods and apparatus are disclosed which eliminate many of the disadvantages associated with known coating processes. The techniques disclosed require only a minor amount of a volatile solvent to achieve atomization and application of a paint or other coating material. High solids coating compositions containing about 70-99% by weight solids are atomized and coated, This method also enables polymeric compositions having high molecular weight to be employed as coating materials. According to techniques described, liquid compositions containing film-forming solids are kept under pressure with a minor amount of a highly volatile solvent of from about 1 to 30% by weight, even as low as about 1-10% by weight, at a temperature above the normal boiling point of the solvent. Such a composition is then atomized by releasing the pressure upon a stream of the composition at a temperature above the normal boiling point of the solvent and below the minimum foam temperature at atmospheric pressure for the composition. The film-forming solids are thus conveyed with or without an external atomizing means.