Method of Surface Treatment for Metal and Nonmetal Surfaces

Abstract

A method of treating the surface of each of a plurality of objects comprising washing the objects; positioning the objects on each of a plurality of structural members; depositing a thin coating on each object; drying the thin coatings; placing the objects and the structural members on a tray in a heating chamber wherein an electric heating unit is disposed in the heating chamber for forming a first metal coat on the thin coating of each object and a second metal coat on each structural member by evaporation; placing the objects and the structural members in a tank filled with electro-coating solution such that after conducting the electro-coating solution positive or negative ions of the electro-coating solution are dissociated and move to the surfaces of the objects for depositing an outer layer thereon; and removing the objects from each structural member.

1 . A method of treating the surface of each of a plurality of objects comprising the steps of:
 (a) washing the objects;   (b) positioning the objects on each of a plurality of structural members;   (c) depositing a thin coating on each object wherein the thin coating is made of acrylic resin, epoxy resin, or nylon resin, and the thin coating is adapted to fill cavities on the surface of each object;   (d) drying the thin coatings;   (e) placing the objects together with the structural members on a tray in a heating chamber wherein an electric heating unit is disposed in the heating chamber and comprises two electrodes of opposite polarities and a tungsten filament interconnecting the electrodes, the tungsten filament being wrapped by metal for evaporation such that evacuating the air in the heating chamber to be vacuum and energizing the heating unit by flowing electric current thereto will evaporate the metal on the tungsten filament into fine particles which are adapted to adhere to the thin coating on each object and each structural member, thereby forming a first metal coat on the thin coating of each object and a second metal coat on each structural member so as to be conductive;   (f) placing the objects and the structural members in a tank filled with electro-coating solution such that after conducting the electro-coating solution positive or negative ions of the electro-coating solution are dissociated and move to the surfaces of the objects for depositing an outer layer thereon wherein the electro-coating solution is either positive electro-coating solution or negative electro-coating solution; and   (g) removing the objects from each structural member;   the method further comprising a conveying device, and wherein the structural member comprises a mating member adapted to secure to a corresponding mating member of the heating chamber for securing the structural member to the heating chamber, a hook adapted to hang on the conveying device, and a plurality of branches adapted to position the objects.   
     
     
         2 . The method of  claim 1 , wherein the objects are metal. 
     
     
         3 . The method of  claim 1 , wherein the objects are nonmetal. 
     
     
         4 . The method of  claim 1 , further comprising a step of drying between steps (f) and (g). 
     
     
         5 . The method of  claim 1 , wherein the thin coatings are dried by heating in a temperature between about 70° C. and 180° C. for a time period between about 20 minutes and about 70 minutes. 
     
     
         6 . The method of  claim 1 , wherein the positive electro-coating solution is formed of positive acrylic resin, positive epoxy resin, or positive polyurethane resin. 
     
     
         7 . The method of  claim 1 , wherein the negative electro-coating solution is formed of negative acrylic resin or negative polyurethane resin. 
     
     
         8 . The method of  claim 1 , wherein each of the first metal coat and the second metal coat has a thickness in a range of about 0.1 μm to about 1.0 μm. 
     
     
         9 . The method of  claim 1 , wherein step (f) is adapted to be replaced by the substeps of:
 (f-1) mixing a coloring agent with the electro-coating solution prior to pouring same into a vessel;   (f-2) placing the objects processed in step (e) in the vessel for dying; and   (f-3) removing the objects to wash and dry so as to form a dyed outer layer on each object.   
     
     
         10 . The method of  claim 9 , wherein the weight of the coloring agent in the electro-coating solution is about 6% to 14% of the weight of the electro-coating solution. 
     
     
         11 . The method of  claim 9 , wherein the vessel is provided with an anode and a cathode, and wherein in electro-coating a direct current is applied to the electro-coating solution for a predetermined period of time and an operating voltage of the electro-coating is in a range of about 40 volts to 190 volts. 
     
     
         12 . The method of  claim 11 , wherein the predetermined period of time is between about 10 seconds to about 50 seconds. 
     
     
         13 . The method of  claim 1 , wherein step (f) is adapted to be replaced by the substeps of:
 (f-4) mixing the electro-coating solution with water and pouring same into a first vessel;   (f-5) placing the objects processed in step (e) in the first vessel;   (f-6) removing the objects to wash and dry;   (f-7) pouring dying agent into a second vessel;   (f-8) placing the objects in the second vessel for dying; and   (f-9) removing the objects to wash and dry so as to form a dyed outer layer on each object.   
     
     
         14 . The method of  claim 1 , wherein the structural members are metal. 
     
     
         15 . The method of  claim 1 , wherein the structural members are nonmetal.