Continuous plasma carrier coating process and apparatus for preparing same

Abstract

The disclosure relates to processes of preparing coated carrier particles by means of plasma activation and apparatus for use thereof.

What is claimed is: 
     
         1 . A process for preparing a coated carrier particle for use in developer compositions, comprising:
 providing a carrier core in a carrier gas;   producing a plasma;   irradiating the carrier core with the plasma to generate a charged carrier core; and   continuously coating the charged carrier core with a polymer to form a polymeric coating.   
     
     
         2 . The process of  claim 1 , wherein the plasma is produced by microwave energy. 
     
     
         3 . The process of  claim 1 , wherein the carrier core has an average particle size of from about 20 μm to about 400 μm in diameter. 
     
     
         4 . The process of  claim 1 , wherein the carrier core comprises a metal, a polymer, or mixtures thereof. 
     
     
         5 . The process of  claim 4 , wherein the metal is selected from the group consisting of iron, steel, ferrites, magnetites, nickel, and mixtures thereof. 
     
     
         6 . The process of  claim 1 , wherein the polymer is selected from the group consisting of acrylates, polyvinylidine flouride, nylons, urethanes, and mixtures thereof. 
     
     
         7 . The process of  claim 1 , wherein the the polymeric coating comprises a copolymer derived from monomers comprising an aliphatic cycloacrylate and an acidic acrylate monomer. 
     
     
         8 . The process of  claim 7 , wherein the aliphatic cycloacrylate is selected from the group consisting of cyclohexylmethacrylate, cyclopropyl acrylate, cyclobutyl acrylate, cyclopentyl acrylate, cyclohexyl acrylate, cyclopropyl methacrylate, cyclobutyl methacrylate, cyclopentyl methacrylate, and mixtures thereof, 
     
     
         9 . The process of  claim 7 , wherein the acidic acrylate monomer is selected from the group consisting of acrylic acid, methacrylic acid, beta-carboxyethyl acrylate, and mixtures thereof. 
     
     
         10 . The process of  claim 7 , wherein the aliphatic cycloacrylate is present in an amount of from about 85% by weight to about 99% by weight of the copolymer. 
     
     
         11 . The process of  claim 7 , wherein the acidic acrylate monomer is present in an amount of from about 0.1% by weight to about 5% by weight of the copolymer. 
     
     
         12 . The process of  claim 1 , wherein the the polymeric coating is present in an amount of from about 0.5% to about 10% by weight based on the total weight of the coated carrier particle. 
     
     
         13 . The process of  claim 1 , wherein the polymeric coating has a thickness of from about 50 mils to about 350 mils. 
     
     
         14 . The process of  claim 1 , wherein the process does not require a mixing of the carrier core and the coating polymer. 
     
     
         15 . A process for preparing a coated carrier particle for use in developer compositions, comprising:
 providing a metal core in a carrier gas;   producing a plasma by microwave energy;   irradiating the carrier core with the plasma to generate a charged carrier core; and   continuously coating the charged carrier core with a polymer to form a polymeric coating.   
     
     
         16 . The process of  claim 15 , wherein the metal core comprises ferrites. 
     
     
         17 . The process of  claim 15 , wherein the polymer is selected from the group consisting of acrylates, polyvinylidine flouride, nylons, urethanes, and mixtures thereof. 
     
     
         18 . The process of  claim 15 , wherein the the polymeric coating is present in an amount of from about 0.5% to about 10% by weight based on the total weight of the coated carrier particle. 
     
     
         19 . The process of  claim 15 , wherein the polymeric coating has a thickness of from about 50 mils to about 350 mils. 
     
     
         20 . An apparatus for preparing a coated carrier particle of  claim 1 , comprising
 a reaction tube for feeding of a carrier core and a carrier gas;   a wave guide for producing plasma;   a microwave resonant cavity for exposing the carrier core and carrier gas to the plasma;   a precursor zone for coating the charged carrier core; and   a tubular furnace for adhering the polymeric coating to the charged carrier core.