PATENTS GRANTED In the Metal Finishing Field Printed copies of patents are furnished by the Patent and Trademark Office for $3.00 each. Address orders to: Commissioner of Patents and Trademarks, Washington, D.C. 20231.

Basecoat/Clearcoat U.S. Patent 5,523,164. June 4, 1996 K. Shibato et aL, assignors to BASF Lacke + Farben AG, Muenster-Hiltrup, Germany

A method for forming a paint film com- prising applying a basecoat including a col- oring and then applying a clearcoat paint and subsequently curing the basecoat and clearcoat simultaneously by heating, wherein the clearcoat paint includes a resin component comprising a copolymer of a vinyl monomer mixture containing at least 20% by weight cycloalkyl esters of acrylic acid or methacrylic acid 40-90% by weight, an alkyl-etherified melamine resin 5-50%, and blocked polyisocyanate com- pounds 5-50%, and the basecoat paint in- cludes a resin component comprising a co- polymer of a vinyl monomer mixture containing at least 10% by weight mono- mers, an alkyl-etherified melamine resin 10-50%, blocked polyisocyanate com- pounds 0-40%, a cellulose resin 0-20%, and crosslinked organic fine particles hav- ing a particle size of 0.01-5 ~am 0-30%.

Waterborne Epoxy U.S. Patent 5,523,336. June 4, 1996 P. Schreiber et aL, assignors to Herberts GmbH, Wuppertal, Germany

An aqueous one-component coating composition for repair of plastic substrates.

In-Mold Coating U.S. Patent 5,523,337. June 4, 1996 K.G. Banerjee et al., assignors to GenCorp Inc., Fairlawn, Ohio

A thermosetting coating composition comprising at least one polymerizable vi- nyl ester resin; 80 to 200 parts by weight of at least one copolymerizable ethylenically unsaturated monomer; 5 to 90 parts by weight of a low profile additive; an effec- tive amount of a mold release agent; and one or more block copolymers.

Powder Coating Composition U.S. Patent 5,523,349. June 4, 1996 Y. Shiomi et aL, assignors to Nippon Paint Co. Ltd., Osaka, Japan

A powder coating composition compris- ing acrylic resin as a main component com- prising at least about 40% by weight of a

glycidyl-group-containing monomer; a sur- face modifier; and polyvalent carboxylic acid.

Resin Composition for Aqueous Coating U.S. Patent 5,523,363. June 4, 1996 T. Fujibayashi and H. Nagaoka, assignors to Kansai Paint Co. Ltd., Hyogo, Japan

A resin composition for aqueous coating characterized by comprising as the main components a resin obtained by reacting an epoxy having at least three epoxy group containing functional groups and an epoxi- dized novolac-substituted phenolic resin.

Method for Shrinking Nickel Electro forms U.S. Patent 5,524,342. June 11, 1996 E.A. Swain et aL, assignors to Xerox Corp., Stamford, Conn.

A method comprising heating a portion of an electroformed hollow cylinder, wherein the cylinder is comprised of nickel and possesses an internal stress sufficient to shrink the diameter of the cylinder upon application of heat, thereby shrinking the diameter of the heated portion; and posi- tioning a part of a member in the portion of the cylinder to be subjected to the heating prior to the shrinkage of the cylinder por- tion, wherein subsequent to the heating the inner surface of the shrunken cylinder por- tion contacts the outer surface of the mem- ber part.

Automotive Paint Booth U.S. Patent 5,524,395. June 11, 1996 M. Boiron, assignor to Omia, Saint Yrieix, France

A painting booth with one end having an opening through which a vehicle can pass; at least one door for closing the opening when a vehicle is enclosed in the booth; a dual section ramp always contained en- tirely within the booth; a first space exist- ing between a lower surface of the ramp and the underlying booth floor; a hinge connecting the fixed section to the move- able section; and a seal extending along the hinge to prevent circulation between a space portion under the moveable section and the space portion under the fixed sec- tion.

Etching Apparatus U.S. Patent 5,524,654. June 11, 1996 T. Nakano, assignor to Kabushi Gaisha Ishfi Hyoki, Hiroshima, Japan

An etching, developing, and peeling ap- paratus for a printed board, the apparatus being provided a fixed height above a con- veyor device having a plurality of juxta- posed shafts and rubber rollers ranked on each shaft at suitable intervals in a length- wise direction so as to carry a printed board in a horizontal posture.

Regeneration of Copper Etchant U.S. Patent 5,524,780. June 11, 1996 G.A. Krulik et aL, assignors to Applied Electroless Concepts Inc., San Clemente, Calif.

A method for the purification of spent ammoniacal alkaline copper etchant contain- ing more than a desired amount of copper in solution, which comprises diluting the spent ammoniacal etchant with substantially iden- tical fresh ammoniacal copper etchant con- taining little or no copper; contacting the diluted spent etchant with at least 20% of the stoichiometric quantity of aluminum metal to react with and precipitate at least some of the copper; allowing the reaction to continue to reduce the amount of copper to less than half of the initial amount; separating the purified etchant solution from the solid copper and aluminum hydroxide precipitates formed by the same reaction, thereby forming a sepa- rated ammoniacal etchant solution; treating the separated etchant solution with suitable additions of an additional solution to recon- stitute the pH, specific gravity, and chemical composition, thereby forming an ammonia- cal alkaline copper etchant suitable for reuse.

Cleaning Apparatus U.S. Patent 5,525,093. June 11, 1996' C.E. Palmer, assignor to Westinghouse Electric Corp., Pittsburgh

A method for cleaning the surface of an object comprising subjecting a portion of liquified carbon dioxide contained in a storage vessel to adiabatic expansion to produce a solid phase carbon dioxide; com- pressing the solid phase carbon dioxide to form a plurality of pellets; producing a first volume of gaseous carbon dioxide at above atmospheric pressure by passing a portion of the liquified carbon dioxide through a

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