Polyamine brightening agent

Abstract

A zinc electroplating bath includes zinc ions and a brightening agent. The brightening agent is a polyamine or a mixture of polyamines that include a quaternary ammonium group.

Having described the invention, the following is claimed: 
     
         1 . A zinc or zinc alloy electroplating bath comprising:
 zinc ions and a brightening agent, the brightening agent comprising at least one polyamine or a mixture of polyamines, the at least one polyamine or mixture of polyamines including a first repeating unit that has the general formula:   
       
         
           
           
               
               
           
         
       
       and a second repeating unit selected from the group consisting of 
       
         
           
           
               
               
           
         
         and combinations thereof; 
         where Δ 1  is O, N, or S; Δ 2  is O, N, or S, and Δ 2 ≠Δ 1 ; x is an integer from 2 to 6; y is an integer from 1 to 6; z is an integer from 1 to 6; R 1 , R 2 , R 3 , and R 4 , which is the same or different, is methyl, ethyl, isopropyl, n-propyl, hydroxyethyl, or —CH 2 CH 2 (OCH 2 CH 2 ) m OH; m is a number between 0-6; R 5  represents a group of atoms necessary to complete a heterocyclic compound having a five or six membered ring containing at least two nitrogen atoms; and R 6  is nothing or an alkyl group. 
       
     
     
         2 . The zinc or zinc alloy electroplating bath of  claim 1 , the first repeating unit having the following formula: 
       
         
           
           
               
               
           
         
       
     
     
         3 . The zinc or zinc alloy plating bath of  claim 1 , the brightening agent comprising a mixture of polyamines, the mixture of polyamines including a first polyamine of the general formula: 
       
         
           
           
               
               
           
         
       
       and a second polyamine of the general formula: 
       
         
           
           
               
               
           
         
       
     
     
         4 . The zinc or zinc alloy plating bath of  claim 1 , the brightening agent comprising a mixture of polyamines, the mixture of polyamines including a first polyamine of the general formula: 
       
         
           
           
               
               
           
         
       
       and a second polyamine of the general formula: 
       
         
           
           
               
               
           
         
       
     
     
         5 . The zinc or zinc alloy electroplating bath of  claim 1 , the first repeating unit and the second repeating unit being in the same polymer chain. 
     
     
         6 . The zinc or zinc alloy electroplating bath of  claim 1 , the polyamine including a repeating unit having the following general formula: 
       
         
           
           
               
               
           
         
       
       where R 7  is an alkylene group. 
     
     
         7 . The zinc or zinc alloy electroplating bath of  claim 1 , the polyamine including a repeating unit having the following general formula: 
       
         
           
           
               
               
           
         
       
       where v is an integer greater than 1. 
     
     
         8 . The zinc or zinc alloy electroplating bath of  claim 1 , the polyamine including a repeating unit having the following general formula: 
       
         
           
           
               
               
           
         
       
     
     
         9 . The zinc or zinc alloy electroplating bath of  claim 1 , the polyamine including a repeating unit having the following general formula: 
       
         
           
           
               
               
           
         
       
     
     
         10 . A zinc or zinc alloy electroplating bath comprising:
 zinc ions and a brightening agent, the brightening agent comprising at least one polyamine or a mixture of polyamines, the at least one polyamine or mixture of polyamines including a first repeating unit that has the general formula:   
       
         
           
           
               
               
           
         
       
       and a second repeating unit selected from the group consisting of: 
       
         
           
           
               
               
           
         
       
       and combinations thereof;
 where Δ 1  is O, N, or S; Δ 2  is O, N, or S, and Δ 2 ≠Δ 1 ; x is an integer from 2 to 6; y is an integer from 1 to 6; z is an integer from 1 to 6; R 1 , R 2 , R 3 , and R 4 , which is the same or different, is methyl, ethyl, isopropyl, n-propyl, hydroxyethyl, or —CH 2 CH 2 (OCH 2 CH 2 ) m OH; m is a number between 0-6; R 5  represents a group of atoms necessary to complete a heterocyclic compound having a five or six membered ring containing at least two nitrogen atoms, and R 6  is nothing or an alkyl group. 
 
     
     
         11 . The zinc or zinc alloy electroplating bath of  claim 10 , the second repeating unit comprising: 
       
         
           
           
               
               
           
         
       
     
     
         12 . The zinc or zinc alloy electroplating bath of  claim 10 , the second repeating unit comprising: 
       
         
           
           
               
               
           
         
       
     
     
         13 . The zinc or zinc alloy electroplating bath of  claim 10 , the second repeating unit comprising: 
       
         
           
           
               
               
           
         
       
     
     
         14 . The zinc or zinc alloy plating bath of  claim 10 , the brightening agent comprising a mixture of polyamines, the mixture of polyamines including a first polyamine of the general formula: 
       
         
           
           
               
               
           
         
       
       and a second polyamine selected from the group consisting of: 
       
         
           
           
               
               
           
         
       
     
     
         15 . The zinc or zinc alloy electroplating bath of  claim 10 , the first repeating unit and the second repeating unit being in the same polymer chain. 
     
     
         16 . The zinc or zinc alloy electroplating bath of  claim 10 , the polyamine including a repeating unit having the following general formula: 
       
         
           
           
               
               
           
         
       
       where R 7  is an alkylene group. 
     
     
         17 . The zinc or zinc alloy electroplating bath of  claim 10 , the polyamine including a repeating unit having the following general formula: 
       
         
           
           
               
               
           
         
       
       where v is an integer greater than 1. 
     
     
         18 . The zinc or zinc alloy electroplating bath of  claim 10 , the polyamine including a repeating unit having the following general formula: 
       
         
           
           
               
               
           
         
       
     
     
         19 . A brightening agent for an alkaline zinc or zinc alloy electroplating bath, the brightening agent comprising a copolymer of a first monomer having the following formula: 
       
         
           
           
               
               
           
         
       
       and at least two of the following compounds selected from the group consisting of: 
       
         
           
           
               
               
           
         
         where Δ 1  is O, N, or S; Δ 2  is O, N, or S, and Δ 2 ≠Δ 1 ; x is an integer from 2 to 6; R 1 , R 2 , R 3 , and R 4 , which is the same or different, is methyl, ethyl, isopropyl, n-propyl, hydroxyethyl, or —CH 2 CH 2 (OCH 2 CH 2 ) m OH; m is a number between 0-6; R 5  represents a group of atoms necessary to complete a heterocyclic compound having a five or six membered ring containing at least two nitrogen atoms; R 6  is nothing or an alkyl group; R 7  and R 8 , which may be the same or different, is an alkylene group; and X 1 , X 2 , and X 3 , which is the same or different, is a halogen.