Acid Zinc
Acid zinc is a brightener process for depositing ductile zinc deposits. Acid zinc has strong dispersing ability and uniform thickness.
COLSID AP-HT PROCESS FOR OBTAINING BRIGHT ZINC DEPOSITS FROM FULL AMMONIUM CHLORIDE PLATING BATHS
Description
COLSID AP-HT is a brightener process for depositing outstanding, brilliant, level, ductile zinc deposits. COLSID AP-HT has the ability to produce bright deposits at extreme low current densities, even at high operating temperatures.
COLSID AP-HT baths operate at extremely high temperatures of 125° F+ (52° C+). COLSID AP-HT contains a special ductiliser compound which insures extremely ductile, bright deposits.
COLSID AP-HT operates with a minimal amount of foam and can be used with air agitation and evaporative recovery.
Equipment
Filtration: Continuous filtration through polypropylene filter tubes of approximately 15 microns is recommended for routine operation. When carbon treatment or another bath purification is necessary, 5-10-micron filter tubes should be substituted.
Equipment: All plating tanks, racks, carriers, etc., which come into contact with COLSID AP-HT solutions, should be plastisol, polyethylene, hard rubber or similarly coated to provide adequate protection from corrosion.
Agitation: Unlike many competitive processes, COLSID AP-HT does not foam excessively and both mechanical and air agitation can be used.
Ventilation: The spray from COLSID AP-HT solutions (not fumes) is inherently corrosive. The use of fiberglass, PVC or polyethylene ventilation equipment and exhaust fans is recommended to prolong equipment life.
Cooling: Cooling coils made from Teflon are optimum, but titanium coils may be used as long as they are insulated from the electrical circuit. Lead or steel coils are not suitable.
COLSID K-250 PROCESS FOR NON-AMMONIATED BRIGHT CHLORIDE ZINC PLATING
Description
COLSID K-250 is an economical brightener process for depositing brilliant, level, ductile zinc deposits in acid chloride zinc plating electrolytes. COLSID K-250 baths contain no ammonium salts.
COLSID K-250 additives have excellent bath solubility compared to competitive systems. COLSID K-250 baths readily plate substrates such as malleable iron castings, heat treated and carbonitrided steels.
COLSID K-250 operates at higher temperatures than competitive systems. COLSID K-250 operates with a minimal amount of foam and can be used with air agitation and evaporative recovery systems.
Equipment
During operation, the only chemical maintenance additions normally required are KCl and boric acid for replenishment due to drag-out losses. Low boric acid causes increased high current density burning. Low chloride causes loss of brightness, leveling and covering power in the low current density.
Zinc Metal: is normally maintained by anodic dissolution during electrolysis. High grade zinc slab anodes of minimum 99.99% purity are recommended as an economical anode source. Anodes may be drilled and tapped or used in titanium anode baskets. No dissolution of anodes occurs during idle periods, and anodes do not have to be removed from the bath during shutdowns. It is recommended to maintain as much anode area as possible to promote good current distribution. High drag-out barrel operations may require supplemental additions of zinc chloride. Acid resistant anode bags of cotton, dynel or polypropylene are optional but recommended for rack operation to reduce anode-caused roughness.
Filtration: continuous filtration through polypropylene filter tubes of approximately 15 microns is recommended for routine operation. When carbon treatment or other bath purification is necessary, 5 – 10-micron filter tubes should be substituted.
Equipment: all plating tanks, racks, carriers etc., which come into contact with COLSID K- 250 solutions, should be plastisol, polyethylene, hard rubber or similarly coated to provide adequate protection from corrosion.
Agitation: unlike many competitive systems, COLSID K-250 does not foam excessively and both mechanical and air agitation can be used.
Ventilation: the spray from COLSID K-250 solutions (not fumes) is inherently corrosive. The use fiberglass, PVC or polyethylene ventilation equipment and exhaust fans is recommended to prolong equipment life.
Cooling Coils: made from Teflon are optimum, but titanium coils may be used as long as they are insulated from the electrical circuit. Lead or steel coils are not suitable.