Continuously manufactured colored metallic products and method of manufacture of such products
View Patent ↗Metallic tube, pipe and conduit are made in a continuous process that includes a zinc galvanization stage, a first passivation stage, a second passivation stage and a third passivation stage. A colorant is added to the tube, pipe or conduit during the continuous manufacturing process, and the colorant imparts the appearance of a color, such as red. The continuous movement of the tube, pipe or conduit is not halted during normal operation of the tube, pipe or conduit manufacturing and coloring process.
1. A method for imparting a colorant to a metallic surface during a continuous manufacturing process, comprising:
in a continuous manufacturing process providing movement of a metallic tube there through, said continuous manufacturing process comprising the steps of:
galvanizing a surface of said metallic tube;
applying first, second and third passivation layers to the galvanized surface; and
providing a colorant on or within at least one of the first, second and third passivation layers;
wherein the colorant is applied in a quench material applied to the tube after galvanizing.
2. The method of claim 1 , wherein the third passivation layer is applied over the second passivation layer before the second and third passivation layers set or fully dry so that said second and third passivation layers intermingle to provide increased interconnectivity there between.
3. The method of claim 1 , wherein at least one of the first, second and third passivation layers contains said colorant, and said passivation layer containing said colorant is applied as a pattern.
4. The method of claim 3 , wherein said patterned passivation layer provides a patterned color appearance to the metallic tube.
5. The method of claim 1 , wherein the colorant is provided on or within the third passivation layer.