Chemistry: electrical and wave energy – Processes and products
Patent
1977-08-23
1979-05-01
Skapars, Anthony
Chemistry: electrical and wave energy
Processes and products
204 38A, 204 58, C25D 1112, C25D 1122
Patent
active
041522222
ABSTRACT:
Anodized aluminium having an anodic oxide film of at least 3 microns thickness is colored by electrolytically depositing inorganic pigment from metallic salt solutions, particularly nickel, cobalt, tin and copper salts and mixtures. The pigment deposits are characterized by outer ends of an average size in excess of 260 A lying at a distance of 500 - 3000 A from the aluminium/aluminium oxide interface.
In a preferred method of production the anodic oxide coating is formed under conventional anodizing conditions in a sulphuric acid-based electrolyte. The anodized aluminium is then treated in phosphoric acid at a voltage of 8 - 50 volts to enlarge the pores to above 260 A in a region at the base of the pores adjacent the barrier layer. The pigment is then deposited in the pores to the specified depth and interesting new color shades are obtained as a result of optical interference due to the presence of the large size shallow inorganic pigment deposits.
REFERENCES:
patent: 3382160 (1978-05-01), Asada
patent: 4066816 (1978-01-01), Sheasby
Wood et al., "The Anodizing of Aluminum in Sulphate Solutions"; Electrochimica Acta (1970) vol. 15 pp. 1865-1876.
Cheetham Graham
Sheasby Peter G.
Alcan Research and Development Limited
Leader William
Skapars Anthony
LandOfFree
Electrolytic coloring of anodized aluminium by means of optical does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Electrolytic coloring of anodized aluminium by means of optical , we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Electrolytic coloring of anodized aluminium by means of optical will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-629975