Process for metallizing nonconductive plastic surfaces

Abstract

The present invention relates to a process for metallizing nonconductive plastics using an etching solution free of hexavalent chromium. The etching solution is based on an sulphuric acidic solution comprising a source of chlorate ions and a vanadium compound. After the treatment of the plastics with the etching solution, the plastics are metallized by means of known processes.

1 - 9 . (canceled) 
     
     
         10 . Process for metallizing electrically nonconductive plastic surfaces of articles, comprising the process steps of:
 A) etching the plastic surface with an etching solution Error! Reference source not found. comprising:
 a) one or more chlorate ion sources, 
 b) one or more vanadium compounds, and 
 c) sulphuric acid; 
   B) treating the plastic surface with a solution of a metal colloid or of a compound of a metal, the metal being selected from the metals of transition group I of the Periodic Table of the Elements and transition group VIII of the Periodic Table of the Elements, and   C) metallizing the plastic surface with a metallizing solution.   
     
     
         11 . Process according to  claim 10 , characterized in that the temperature during process step A) is kept between 20 and 65° C. 
     
     
         12 . Process according to  claim 10 , characterized in that the temperature during process step A) is kept between 40 and 65° C. 
     
     
         13 . Process according to  claim 10 , characterized in that the metal in process step B) is palladium. 
     
     
         14 . Process according to  claim 10 ,
 characterized in that the plastic surface has been manufactured from at least one electrically nonconductive plastic and the at least one electrically nonconductive plastic is selected from an acrylonitrile-butadiene-styrene copolymer, a polyamide, a polycarbonate and a mixture of an acrylonitrile-butadiene-styrene copolymer with at least one further polymer.   
     
     
         15 . Process according to  claim 10 , characterized in that the following further process step is performed between process steps A) and B):
 A i) treating the plastic surface in a solution comprising a reducing agent for chlorate ions.   
     
     
         16 . Process according to  claim 15 , characterized in that the reducing agent is selected from the group consisting of hydroxylammonium sulphate, hydroxylammonium chloride and hydrogen peroxide. 
     
     
         17 . Process according to  claim 10 , characterized in that the following further process step is performed between process steps A) and B):
 A i) treating the plastic surface in a solution comprising a neutralizing agent comprising a source of hydroxide ions.   
     
     
         18 . Process according to  claim 10 , characterized in that the following further process steps are performed between process steps B) and C):
 B i) treating the plastic surface in an aqueous acidic solution and   B ii) electrolessly metallizing the plastic surface in a metallizing solution.   
     
     
         19 . Process according to  claim 15 , characterized in that the following further process steps are performed between process steps B) and C):
 B i) treating the plastic surface in an aqueous acidic solution and   B ii) electrolessly metallizing the plastic surface in a metallizing solution.   
     
     
         20 . Process according to  claim 17 , characterized in that the following further process steps are performed between process steps B) and C):
 B i) treating the plastic surface in an aqueous acidic solution and   B ii) electrolessly metallizing the plastic surface in a metallizing solution.