Method for preparing plastic particles coated with metal

Abstract

The present invention relates to a method for preparing plastic particles coated with metal, which comprises the following steps. First, mix a plurality of plastic particles with a tin/palladium solution to form a first mixed liquid. Alternatively, first mix the plurality of plastic particles with a stannous chloride/hydrochloric acid solution. Then mix the plurality of plastic particles adsorbing the plurality of stannous ions with a palladium chloride/hydrochloric acid solution and form the first mixed liquid. Next, microwave the first mixed liquid so that the tin/palladium colloidal particles coat the plastic particles and thus forming first metal particles. Afterwards, mix the first metal particles with an electroless nickel solution and form a second mixed liquid. Metal nickel then coats the first metal particles and forming a plurality of second metal particles. Use microwave to activate the plurality of tin/palladium colloidal particles adsorbed on the surfaces of the plastic particles, and hence increasing adsorption of the plated metal layer on the surfaces of the plastic particle. Thereby, roughness and peeling-off of the plated metal layer can be reduced.

1 . A method for preparing plastic particles coated with metal, comprising steps of:
 mixing a plurality of plastic particles with a tin/palladium solution and forming a first mixed liquid, said plurality of plastic particles adsorbing a plurality of tin/palladium colloidal particles in said tin/palladium solution;   microwaving said first mixed liquid such that said plurality of tin/palladium colloidal particles coat said plurality of plastic particles and forming a plurality of first metal particles;   mixing said plurality of first metal particles with an electroless nickel solution and forming a second mixed liquid, said plurality of first metal particles coated with metal nickel and forming a plurality of second metal particles; and   filtering said plurality of second metal particles from said second mixed liquid.   
     
     
         2 . The method for preparing plastic particles coated with metal of  claim 1 , and further comprising a step of stirring said first mixed liquid after said step of mixing said plurality of plastic particles with said tin/palladium solution and forming said first mixed liquid. 
     
     
         3 . The method for preparing plastic particles coated with metal of  claim 1 , and, after said step of microwaving said first mixed liquid, further comprising steps of:
 filtering said plurality of first metal particles;   rinsing said plurality of first metal particles; and   baking said plurality of first metal particles.   
     
     
         4 . The method for preparing plastic particles coated with metal of  claim 1 , and further comprising a step of heating and stirring said second mixed liquid after said step of mixing said plurality of first metal particles with said electroless nickel solution and forming said second mixed liquid. 
     
     
         5 . The method for preparing plastic particles coated with metal of  claim 1 , wherein:
 the ratio in weight of said first metal particles to said electroless nickel solution is 1/200 to 1/500 in said step of mixing said plurality of first metal particles with said electroless nickel solution and forming said second mixed liquid;   the material of said plurality of plastic particles includes polymethylmethacrylate, epoxy resin, or polystyrene, and the shape of said plurality of plastic particles is true-ball, ellipsoid, or hollow-ball shaped in said step of mixing said plurality of plastic particles with said tin/palladium solution and forming said first mixed liquid;   a microwave reactor is used for microwaving said first mixed liquid with power ranging between 30 and 300 Watts for 3 to 30 minutes in said step of microwaving said first mixed liquid;   said plurality of second metal particle have a metal shell made of a material containing nickel, gold, or copper with a thickness around 30 to 300 nanometers in said step of filtering said plurality of second metal particles from said second mixed liquid; and   an air exhauster or a centrifuge is used for filtering said plurality of second metal particles in said step of filtering said plurality of second metal particles from said second mixed liquid.   
     
     
         6 . A method for preparing plastic particles coated with metal, comprising steps of:
 mixing a plurality of plastic particles with a stannous chloride/hydrochloric acid solution such that said plurality of plastic particles adsorb a plurality of stannous ions in said stannous chloride/hydrochloric acid solution;   mixing said plurality of plastic particles adsorbing said plurality of stannous ions with a palladium chloride/hydrochloric acid solution and forming a first mixed liquid, so that said plurality of plastic particles adsorb a plurality of palladium ions;   microwaving said first mixed liquid such that a plurality of tin/palladium colloidal particles coat said plurality of plastic particles and forming a plurality of first metal particles;   mixing said plurality of first metal particles with an electroless nickel solution and forming a second mixed liquid, said plurality of first metal particles coated with metal nickel and forming a plurality of second metal particles; and   filtering said plurality of second metal particles from said second mixed liquid.   
     
     
         7 . The method for preparing plastic particles coated with metal of  claim 6 , and further comprising a step of stirring said stannous chloride/hydrochloric acid solution after said step of mixing said plurality of plastic particles with said stannous chloride/hydrochloric acid solution. 
     
     
         8 . The method for preparing plastic particles coated with metal of  claim 6 , and further comprising a step of stirring said first mixed liquid after said step of mixing said plurality of plastic particles adsorbing said plurality of stannous ions with said palladium chloride/hydrochloric acid solution and forming said first mixed liquid. 
     
     
         9 . The method for preparing plastic particles coated with metal of  claim 6 , and, after said step of microwaving said first mixed liquid, further comprising steps of:
 filtering said plurality of first metal particles;   rinsing said plurality of first metal particles; and   baking said plurality of first metal particles.   
     
     
         10 . The method for preparing plastic particles coated with metal of  claim 6 , wherein:
 after said step of mixing said plurality of first metal particles with said electroless nickel solution and forming said second mixed liquid, a step is further included for heating and stirring said second mixed liquid;   the ratio in weight of said first metal particles to said electroless nickel solution is 1/200 to 1/500 in said step of mixing said plurality of first metal particles with said electroless nickel solution and forming said second mixed liquid;   the material of said plurality of plastic particles includes polymethylmethacrylate, epoxy resin, or polystyrene, and the shape of said plurality of plastic particles is true-ball, ellipsoid, or hollow-ball shaped in said step of mixing said plurality of plastic particles with said tin/palladium solution and forming said first mixed liquid;   a microwave reactor is used for microwaving said first mixed liquid with power ranging between 30 and 300 Watts for 3 to 30 minutes in said step of microwaving said first mixed liquid:   said plurality of second metal particle have a metal shell made of a material containing nickel, gold, or copper with a thickness around 30 to 300 nanometers in said step of filtering said plurality of second metal particles from said second mixed liquid; and   
       an air exhauster or a centrifuge is used for filtering said plurality of second metal particles in said step of filtering said plurality of second metal particles from said second mixed liquid.