A method for activating a surface of a non-conductive or carbon-fibres containing substrate for metallization

Abstract

Method for activating a surface of a non-conductive or carbon-fibres containing substrate for metallization, the method including: (a) providing said substrate, (b) providing an aqueous, palladium-free activation composition comprising (i) a first species of dissolved transition metal ions and additionally metal particles thereof, (ii) at least one complexing agent, (iii) permanently or temporarily at least one reducing agent, (iv) optionally one or more second species of dissolved metal ions different from the first species, (c) contacting the substrate with said activation composition such that a transition metal or a transition metal alloy is deposited on the surface of said substrate and an activated surface for metallization is obtained.

1 . A method for activating a surface of a non-conductive or carbon-fibres containing substrate for metallization, the method comprising the steps
 (a) providing said substrate,   (b) providing an aqueous, palladium-free activation composition comprising
 (i) a first species of dissolved transition metal ions and additionally metal particles thereof, 
 (ii) one or more than one complexing agent, 
 (iii) permanently or temporarily one or more than one reducing agent, 
 (iv) optionally one or more than one second species of dissolved metal ions being different from the first species, 
 wherein
 at least of the first species, the dissolved transition metal ions and the metal particles thereof are present in a reversible equilibrium, with the proviso that
 the metal particles are formed from the dissolved transition metal ions through a continuous or semi-continuous reduction through the one or more than one reducing agent, 
 the dissolved transition metal ions are formed from the metal particles through continuous or semi-continuous oxidation of said particles, and 
 the dissolved transition metal ions and the metal particles thereof, respectively, are repeatedly involved in said reduction and said oxidation such that no precipitating agglomerates of said metal particles are formed, 
 
 
   (c) contacting the substrate with said activation composition such that a transition metal or a transition metal alloy is deposited on the surface of said substrate and an activated surface for metallization is obtained.   
     
     
         2 . The method of  claim 1 , wherein during and/or after step (c) the majority of said metal particles is subjected to said oxidation. 
     
     
         3 . The method of  claim 1 , wherein the first species is copper or cobalt. 
     
     
         4 . The method of  claim 1 , wherein the metal particles of the first species in the activation composition are colloidal metal particles. 
     
     
         5 . The method of  claim 1 , wherein the metal particles of the first species are continually or semi-continually formed in situ in the activation composition by said reduction after and/or during one or more than one step (c) is carried out. 
     
     
         6 . The method of  claim 1 , wherein the one or more than one reducing agent comprises a boron-containing reducing agent. 
     
     
         7 . The method of  claim 1 , wherein the activation composition is substantially free of or does not comprise any of tin ions, lead ions, germanium ions, gallium ions, antimony ions, bismuth ions, and aluminium ions. 
     
     
         8 . The method of  claim 1 , wherein the activation composition is substantially free of or does not comprise a compound preventing the oxidation of the metal particles and/or is substantially free of or does not comprise a stabilizer compound to stabilize the metal particles. 
     
     
         9 . The method of  claim 1 , wherein the one or more than one reducing agent is continually or semi-continually added to the activation composition such that further metal particles are continually or semi-continually, respectively, formed from the dissolved transition metal ions of the first species. 
     
     
         10 . The method of  claim 1 , wherein the dissolved transition metal ions are formed from the metal particles through oxidation by ambient air and/or oxygen gas. 
     
     
         11 . The method of  claim 1 , further comprising a pre-treatment step for the substrate prior to step (c):
 (a-1) treating said substrate with a pre-treatment solution comprising a nitrogen-containing compound.   
     
     
         12 . A method for metallizing an activated surface of a non-conductive or carbon-fibres containing substrate, the method comprising the steps
 (A) providing the non-conductive or carbon-fibres containing substrate with the activated surface for metallization obtained by a method for activating according to  claim 1 ,   (B) metallizing the activated surface by contacting the activated surface with a first metallizing solution such that a first metallization layer is deposited on the activated surface.   
     
     
         13 . A method for preparing an aqueous, palladium-free activation composition for activating a surface of a non-conductive or carbon-fibres containing substrate for metallization, the method comprising the steps:
 (1) providing an aqueous starting solution comprising:
 a first species of dissolved transition metal ions, 
 one or more than one complexing agent, and 
 optionally one or more than one second species of dissolved metal ions being different from the first species, 
   (2) continually or semi-continually adding one or more than one reducing agent to the starting solution such that metal particles of at last the first species of dissolved transition metal ions are continually or semi-continually, respectively, formed in the solution,   with the proviso that said metal particles are continually or semi-continually oxidized to form dissolved transition metal ions of the first species.   
     
     
         14 . (canceled) 
     
     
         15 . An aqueous, palladium-free activation composition for activating a surface of a non-conductive or carbon-fibres containing substrate for metallization, the composition comprising
 (i) a first species of dissolved transition metal ions and additionally metal particles thereof,   (ii) one or more than one complexing agent,   (iii) permanently or temporarily one or more than one reducing agent,   (iv) optionally one or more than one second species of dissolved metal ions being different from the first species,   wherein
 at least of the first species, the dissolved transition metal ions and the metal particles thereof are present in an reversible equilibrium, with the proviso that
 the metal particles are formed from the dissolved transition metal ions through a continuous or semi-continuous reduction through the one or more than one reducing agent, 
 the dissolved transition metal ions are formed from the metal particles through continuous or semi-continuous oxidation of said particles, and 
 the dissolved transition metal ions and the metal particles thereof, respectively, are repeatedly involved in said reduction and said oxidation such that no precipitating agglomerates of said metal particles are formed.