Roger E Democh

US Patent:

40512789, Sep 27, 1977

Filed:

Jun 6, 1975

Appl. No.:

5/584322

Inventors:

Roger E. Democh - Rochester NY

Assignee:

Eastman Kodak Company - Rochester NY

International Classification:

B05D 300
B05D 304

US Classification:

427326

Abstract:

In coating a support, such as a flexible web of synthetic organic polymer, with a coating composition comprising a film-forming material in an evaporable liquid vehicle, at least two of (1) the temperature of the atmosphere in the coating zone, (2) the temperature of the coating composition at the point where it is coated on the support, and (3) the temperature of the support at the point where the coating composition is applied thereto, are maintained at a temperature substantially equivalent to the equilibrium surface temperature of the coated layer within the coating zone. The equilibrium surface temperature is defined as the temperature assumed by the surface of a layer of the coating composition under steady state conditions of heat transfer following evaporative cooling of the layer in the coating zone. Such temperature control minimizes thermal gradients within the coated layer and significantly reduces the formation of mottle and similar coating defects. The method is especially useful in the coating of organic solvent solutions of polymeric resins and finds particular application in the manufacture of photographic elements.