Abstract: According to a preferred embodiment of this invention, the exterior surface of an evaporator carries a coating of dried paint resistant to microbial growth and suitable for forming an adhered layer on cooling surfaces of an air conditioner. This paint comprises a pigment, a liquid, a binder to promote formation and adherence of the coating after the paint is applied and dried, and a metallic constituent which inhibits microbial growth. Preferably, the metallic constituent is inorganic and includes one or more of: copper, cupric carbonate, cuptic hydroxide, cuptic oxide, cuprous oxide, silver, silver oxide, zinc oxide, and zinc peroxide. The coating is preferably applied to the integral core after assembling and brazing the several plates and fins of the core.

Abstract: In a preferred embodiment of the invention, an evaporator core for an automotive air conditioning system or the like comprises a brazed plate-and-fin heat exchanger formed of aluminum alloy and having air passages opening at an upstream face. The evaporator core further comprises a biocidal fixture attached to the heat exchanger upstream face. The fixture comprises a carrier formed of an electrically nonconductive polymer and metallic copper plate deposited on the surface of the carrier spaced apart from the heat exchanger. During air conditioning operations, condensate collecting on the cooper surfaces reacts with the copper to generate cupric ions that disperse in the condensate to inhibit biological growth within the heat exchanger passages. Moreover, the carrier electrically, as well as physically, isolated the copper from the aluminum to prevent galvanic coupling that would otherwise produce accelerated corrosion of the heat exchanger.

Abstract: A method of preparing the surface of molded mineral-filled nylon to receive an adherent electrodeposited metal coating comprising the steps of: exposing the surface to a plasma glow discharge; vacuum depositing a film of chromium or titanium onto the plasma-treated surface; vacuum depositing a nickel film onto the chromium or titanium film to prevent oxidation thereof; and then vacuum depositing a copper film onto the nickel film. The plasma gas is preferably inert (e.g., argon, helium, etc.) and metal deposition is effected so as to avoid oxidation of the chromium/titanium and nickel films during processing.

Abstract: A method of forming adherent electrodeposited coatings on ABS and PPO comprising the steps of etching and bonding oxygen to an ABS or PPO surface in an RF oxygen glow discharge, vacuum depositing a metal having an affinity for oxygen, and then vacuum depositing a readily electroplatable metal. Even decorative chrome electroplatings can be performed without producing blistering or peeling.

Abstract: A process and apparatus designed to recover metal ions from a solution in which the anode is in the form of a vortex diffuser. The vortex diffuser radiates an electrolyte solution upon an ion collector plate in such a manner that the fluid impinges upon the collector perpendicular and then turning parallel to its surface to thereby wipe away any tendency toward dendritic metal formation.