liquid ion exchanger with a washing water; neutralizing the washing water with lime so as to obtain a neutralized washing water; filtering the neutralized washing water; and recovering copper electrolytically.

Aqueous Spot Fillers U.S. Patent 5,520,955. May 28, 1996 0. Natvotka, assignor to Herberts G&H, Wuppetiaal, Germany

A process for repairing a defective coat- ing of a motor vehicle body, which com- prises applying the following aqueous spot filler to the defective portion of the body, said aqueous spot filler containing at least one water-dilutable, olefinically unsatur- ated binder, conventional pigments, fillers, and adjuvants, corresponding to a solids content of 50-90% by weight, lWO% of water, and O-10% of one or more organic solvents.

Coated Abrasive U.S. Patent 5,520,957. May 28, 1996 D. W Sange et a/, assignors to 3M Co., St. Paul, Minn.

A method of preparing a coated abrasive article containing a pressure-sensitive ad- hesive, comprising providing a coated

abrasive article having a backing bearing on one major surface thereof a layer of abrasive grains, said abrasive grains ad- hered to the backing by at least one binder, providing a pressure-sensitive adhesive comprising a water-emulsifiable, tacky ad- hesive formed from a copolymer of vinyl acetate and at least one terminally unsatur- ated vinyl monomer; coating the adhesive onto a major surface of the backing not bearing the layer of abrasive grains; smoothing the coated adhesive sufficiently to prevent formation of a pattern of ridges in the coating; and drying.

Surface Treatment for Tin-Plated Cans U.S. Patent $520,959. May 28, 1996 S. Tanaka et al, assignors to Heflkel Corp., Plymouth Meeting, Pa.

A method for treating at least the outer surface of a tin-plated, drawn, and ironed can wherein the precleaned surface to be treated is sprayed for at least 5 set at a temperature of at least 40°C with an aqeu- ous surface treatment liquid having a pH between 4 and 6 and comprising 0.03 to 0.3% by weight of acids selected from the group consisting of orthophosphoric acid

and condensed phosphoric acids and a con- centration of at least 0.1% of a water- soluble oligomer.

Plastisol-Based Coating U.S. Patent 5,520,961. May 28, 1996 L. Lysell and /_. Mahbom, assignors to Casco Nobel AB, Stockholm, Sweden

A method for spray coating a surface with a coating composition containing vinyl-chlo- ride-polymer-based plastisol and expandable thermoplastic microspheres, wherein the ex- pandable thermoplastic microspheres have a substantially halogen-free polymer shell, which comprises a copolymer of halogen- free monomers and, in an amount of from 85 to 97% by weight, &rile-containing mono- mers, and the coating composition is applied by airless spraying.

Paint Formulation U.S. Patent 5,520,963. May 28, 1996 TZ. Liu, assignor to DuPont Canada Inc., Mississauga, Canada

A method of spraying an article with urethane paint comprising adding cellulose acetate to the urethane paint; said cellulose acetate butyrate having a viscosity equal to or greater than 0.5 set and less than 20 set;

99% - Removal Efficiency or Greater I

Maximum Corrosion Resistance

Eliminates Orange- Brown

, Plume I

Circle 031 on reader information card Circle 075 on reader information card

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