Method of inhibiting darkening, blackening or tarnishing of aluminium and aluminium alloys and compositions therefore

• Main Authors: DAVID C. SILVERMAN, TIMOTHY K. HIRZEL
• Format: Patent
• Language: English
• Published: 14.02.2000
• Edition: 7
• Subjects: CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; FUELS; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; LUBRICANTS; LUBRICATING COMPOSITIONS; METALLURGY; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLICMATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASSC23 AND AT LEAST ONEPROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25; NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; PEAT; PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATINGINGREDIENTS IN A LUBRICATING COMPOSITION

There is disclosed a method of inhibiting darkening, blackening or tarnishing of aluminium and aluminium alloys comprising contacting an aluminium alloy with a fluid composition containing a composition in an amount effective to inhibit darkening, blackening or tarnishing of the surface of the aluminium or aluminium alloy at an effective pH, and compositions therefore. Also disclosed are aqueous metal working fluid compositions containing the compositions of the invention.