Process for forming a protective coating on zinciferous metal surfaces
First Claim
1. A process of forming, over a specified period of time, a protective coating on one or more zinciferous surface(s) by contacting the surface(s) with at least a portion of a specified total volume of an aqueous liquid treatment composition comprising water, transition metal cations, and fluorometallate anions, said process including steps of:
- (I) measuring a pH value of, a transition metal cations concentrations in, and a fluorometallate anions concentrations in, the specified total volume of treatment composition as it is used;
(II) at at least one specified time after beginning use of the specified total volume of the treatment composition, said specified time being within said specified period of time over which the process is operated and being not more than 200 minutes, and, if the specified period of time is at least 400 minutes, also at one or more successive times thereafter, removing a specified fraction of the total volume of the treatment composition from contact with the remainder of the total volume of the treatment composition, said one or more successive times thereafter being selected so that not more than 200 minutes elapses between any such successive time and a most nearly preceding time at which a specified total fraction of the specified total volume of the treatment composition has been removed from contact with the remainder of the specified total volume of the treatment composition, said specified fraction or fractions of the specified total volume of the treatment being selected so that a ratio of said specified period of time, measured in hours, to a sum of all said specified fraction or fractions of the specified total volume that are removed from contact with the remainder of the specified total volume during said period of time has a numerical value not greater than 100; and
(III) adding one or more suitable replenisher compositions to the treatment composition, in order to maintain the pH value of the composition, the transition metal cations concentration of the composition, and the fluorometallate anions concentrations of the composition within respectively specified ranges for each of the pH value, the transition metal cations concentration, and the fluorometallate anions concentration.
1 Assignment
0 Petitions
Accused Products
Abstract
More nearly consistent quality of the coatings formed by contacting a zinciferous surface with an aqueous liquid treatment composition comprising water, transition metal cations, and fluorometallate anions, and, optionally, acidity adjustment agents can be achieved by (I) measuring the pH value of and the concentrations of transition metal cations and of fluorometallate anions in the treatment composition as it is used, (II) removing a specified fraction of the treatment composition from contact with the remainder of the treatment composition, and (III) adding one or more suitable replenisher compositions to the treatment composition, in order to maintain the measured pH and concentration values within specified ranges.
3 Citations
20 Claims
-
1. A process of forming, over a specified period of time, a protective coating on one or more zinciferous surface(s) by contacting the surface(s) with at least a portion of a specified total volume of an aqueous liquid treatment composition comprising water, transition metal cations, and fluorometallate anions, said process including steps of:
-
(I) measuring a pH value of, a transition metal cations concentrations in, and a fluorometallate anions concentrations in, the specified total volume of treatment composition as it is used; (II) at at least one specified time after beginning use of the specified total volume of the treatment composition, said specified time being within said specified period of time over which the process is operated and being not more than 200 minutes, and, if the specified period of time is at least 400 minutes, also at one or more successive times thereafter, removing a specified fraction of the total volume of the treatment composition from contact with the remainder of the total volume of the treatment composition, said one or more successive times thereafter being selected so that not more than 200 minutes elapses between any such successive time and a most nearly preceding time at which a specified total fraction of the specified total volume of the treatment composition has been removed from contact with the remainder of the specified total volume of the treatment composition, said specified fraction or fractions of the specified total volume of the treatment being selected so that a ratio of said specified period of time, measured in hours, to a sum of all said specified fraction or fractions of the specified total volume that are removed from contact with the remainder of the specified total volume during said period of time has a numerical value not greater than 100; and (III) adding one or more suitable replenisher compositions to the treatment composition, in order to maintain the pH value of the composition, the transition metal cations concentration of the composition, and the fluorometallate anions concentrations of the composition within respectively specified ranges for each of the pH value, the transition metal cations concentration, and the fluorometallate anions concentration. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20)
-
Specification