Method for Metallising Objects Which Have at Least Two Different Plastics on the Surface

Abstract

The following method is to improve selectivity during metallisation of surface areas to be metallised on objects 7 having different plastics while not allowing the areas not to be metallised to be metallised: A) etching of the objects 7 with an etching solution; B) treatment of the objects 7 with a solution of a colloid or with a metal compound, the metal being a metal of Group VIIIB or IB of the Periodic Table of the Elements; and C) electrolytic metallisation of the objects 7 with a metallisation solution. The objects 7 are subjected to ultrasonic treatment during the treatment in a further method step following method step B) and before method step C) in order to avoid metallisation of at least one first plastic exposed on the surface of the objects 7 while at least one second plastic exposed on the surface of the objects 7 is metallised.

1 . A method for metallising objects which have at least two different plastics on the surface, comprising the following method steps:
 A) Etching of the objects with an etching solution;   B) Treating the objects with a solution of a colloid or with a solution of a metal compound, the metal being a metal of Group VIIIB or IB of the Periodic Table of the Elements;   C) Electrolytically metallising the objects with a metallisation solution, the method further comprising subjecting the objects to ultrasonic treatment during a treatment in an additional method step performed after performing method step B) and before method step C), not however in electroless depositing of metal, to avoid metallisation of at least one first plastic exposed on the surface of the objects while at least one second plastic exposed on the surface of the objects is metallised.   
     
     
         2 . The method according to  claim 1 , wherein the second plastic is a plastic selected from the group comprising an acrylnitrile-butadiene-styrol copolymer (ABS copolymer), a polyamide, and a mixture of an ABS copolymer with at least one polymer which is different to the ABS copolymer. 
     
     
         3 . The method according to  claim 2 , wherein the at least one other polymer which is different to the ABS polymer is a polycarbonate. 
     
     
         4 . The method according to  claim 2 , wherein the first plastic is a polycarbonate or a covering lacquer used to prevent metallisation of the object. 
     
     
         5 . The method according to  claim 1 , further comprising at least one of the following further method steps between method steps B) and C):
 Ba1) Rinsing the objects in a rinsing solution;   Bb1) Treating the objects in an accelerating solution or a reducing agent solution;   Bc1) Rinsing the objects in a rinsing solution;   Bd1) Electroless metallising the objects in an metallisation solution; and   Be1) Rinsing the objects in a rinsing solution.   
     
     
         6 . The method according to  claim 5 , further comprising subjecting the objects to ultrasonic treatment during treatment in at least one of the method steps Ba1), Bb1), Bc1), Be1). 
     
     
         7 . The method according to  claim 1 , further comprising at least one of the following further method steps between method steps B) and C):
 Ba2) Rinsing the objects in a rinsing solution;   Bb2) Treating the objects in a conversion solution so that an sufficiently electrically conductive layer is formed on the surface of the objects for direct electrolytic metallisation; and   Bc2) Rinsing the objects in a rinsing solution.   
     
     
         8 . The method according to  claim 7 , further comprising subjecting the objects to ultrasonic treatment during treatment in at least one of the method steps Ba2), Bb2), Bc2). 
     
     
         9 . The method according to  claim 1 , further comprising immersing the objects in treatment tanks containing the respective solutions to execute the method steps and providing at least one ultrasound emitter in the respective solution in the treatment tank in which an ultrasonic treatment is carried out to expose the objects to ultrasound. 
     
     
         10 . The method according to  claim 9 , further comprising arranging the ultrasound emitter on one side of the objects and arranging an ultrasound reflector or a further ultrasound emitter on the other side of the objects. 
     
     
         11 . The method according to  claim 1 , wherein the etching solution is a chromic acid/sulfuric acid solution. 
     
     
         12 . The method according to  claim 1 , wherein the solution of the colloid is an activator solution comprising a palladium/tin colloid. 
     
     
         13 . The method according to  claim 3 , wherein the first plastic is a polycarbonate or a covering lacquer used to prevent metallisation of the object.