prising a chamber, means at the upper portion for heating the chamber interior and materials contained therein from the top downwardly; means for controlling the heating means so as to vaporize volatile constituents of the materials; and means at the lower portion for exhausting the vapor- ized volatile constituents.

Current Control System U.S. Palent5,352,346. Oct. 4, 1994 D. Rof$iguez, assignor to Novamax Technologies Hddngs Inc., Oniafio, Canada

A current generation and control system for an electrolytic vat.

Process for Metallization of Ceramic Substrates U.S. Pafent5,352,326. Oct. 4, 1995 0. Cywaf ef al., assignors to lntemational Business Machines Corp., EMcofi, N. K

A method for selectively etching metal from a substrate comprising of steps of providing an acrylic negative photoresist; applying the photoresist to the substrate; imaging the photoresist; developing the photoresist; exposing the photoresist to actinic radiation comprising wavelengths

selected from the group consisting of 200-310 nm or 2.4-8 microns; then con- tacting the photoresist coated substrate with an etchant so as to remove portions of the metal not covered by the photoresist.

Autodeposition Coating U.S. Patent 5352,726. Ocf. 4, 1994 MS. Ha//, assignor to Her&e/ Cop., Ambler, Pa.

An autodepositing composition compris- ing an acidic aqueous solution of activator consisting essentially of hydrofluoric acid in an amount sufficient to impart to the composition a pH within the range of 1.6-5.0 and a soluble ferric-iron-containing compound in an amount equivalent to about 0.025-3.5 g/L of ferric iron and having dispersed therein resin solids of an inter- nally stabilized copolymer comprising at least about 80% by weight of vinylidene chloride; one or more monomers selected from the group consisting of methacrylic acid, acrylic acid, methyl methacrylate, methyl acrylate, ethyl acrylate, butyl acrylate, acrylonitrile, methacrylonitrile, vinyl chloride, acrylamide and meth- acrylamide; and a water-soluble ionic ma- terial, which includes an inorganic ioniza- ble sulfonate group.

Pickling and Passivating Stainless Steel Without Nitric Acid U.S. Patent 5,354,383. Oct. 11, 1994 h4. Bianchi, assignor to ITB, S.r./., Milan, My

A process for pickling and passivating stainless steel, consisting of contacting with a bath maintained at a temperature between 30 and 7OT preferably between 45 and WC, and having the following initial composition of at least 150 g/L sulfuric acid; at least 15 g/L ferric ion; at least 40 g/L hydrofluoric acid; l-20 and preferably 2-5 g/L hydrogen peroxide; additives of the nonionic surfactant type and acid attack inhibitor type about 1 g/L in total. Continuously feeding into the bath an air flow of at least 3 m3/hr per m3 of bath, using a suitable distributor device for diffusing the flow into the liquid mass; a quantity of stabilized hydrogen peroxide of between 0.3 and 1 g/L per hour, controlled on the basis of the redox potential of the bath, which must be maintained at 2350 mV, and possibly sufficient quantities of ingredients to maintain their concentration in the bath at optimum levels and the bath pH between 0 and 0.5.

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