Antimicrobial Glaze and Porcelain Enamel via Double Layer Glaze with High Zinc Content

Abstract

A cost-effective and practical antimicrobial glaze system and glazing process is disclosed herein. The antimicrobial glaze/enamel may comprise at least two layers: a base layer and a top layer. The base layer may contain a typical or normal glaze widely used in sanitary ware, having a low level of zinc oxide. The base layer glaze may be directly sprayed on the clay body surface. A thin top glaze layer is sprayed on top of the base glaze layer and the top layer may contain a high level of zinc oxide.

1 . Sanitary ware comprising a multilayer antimicrobial ceramic glaze, the ceramic glaze comprising
 a base glaze layer containing from 0.0 percent by weight to about 8.0 percent by weight ZnO; and   a top glaze layer containing from about 8.0 percent by weight to about 35.0 weight percent ZnO,   wherein the top glaze layer comprises a higher weight percent of ZnO than the base glaze layer.   
     
     
         2 . The sanitary ware of  claim 1 , wherein the top layer contains from about 10.0 weight percent to about 25.0 weight percent ZnO. 
     
     
         3 . The sanitary ware of  claim 1 , wherein the base layer contains ZnO. 
     
     
         4 . The sanitary ware of  claim 1 , wherein the base layer contains from about 0.0 weight percent to about 6.0 weight percent ZnO. 
     
     
         5 . The sanitary ware of  claim 1 , wherein the ceramic glaze is substantially free of surface defects. 
     
     
         6 . The sanitary ware of  claim 1 , wherein the base glaze layer is from about 300 μm to about 1000 μm thick. 
     
     
         7 . The sanitary ware of  claim 1 , wherein the base glaze layer is from about 300 μm to about 600 μm thick. 
     
     
         8 . The sanitary ware of  claim 1 , wherein the top glaze layer is from about 25 μm to about 250 μm thick. 
     
     
         9 . The sanitary ware of  claim 1 , wherein the top glaze layer is from about 25 μm to about 150 μm thick. 
     
     
         10 . The sanitary ware of  claim 1 , wherein the top glaze layer is from about 100 μm to about 200 μm thick. 
     
     
         11 . The sanitary ware of  claim 1 , wherein the top glaze layer is from about 150 μm to about 300 μm thick. 
     
     
         12 . The sanitary ware of  claim 1 , wherein the top glaze layer is from about 200 μm to about 300 μm thick. 
     
     
         13 . The sanitary ware of  claim 1 , wherein a top 10 μm of the top glaze layer contains more than 8 weight percent and less than 35.0 weight percent ZnO. 
     
     
         14 . The sanitary ware of  claim 1 , wherein a top 10 μm of the top glaze layer contains more than 8 weight percent and less than 15.0 weight percent ZnO. 
     
     
         15 . The sanitary ware of  claim 1 , wherein the top glaze layer includes a source of ions selected from one or more of Hg, Ag, Cu, Fe, Pb, Bi, and rare earths. 
     
     
         16 . The sanitary ware of  claim 1 , wherein a total ZnO content in the multilayer glaze is less than 5.0 weight percent. 
     
     
         17 . A method of producing the sanitary ware of  claim 1 , the method comprising
 applying a base glaze material onto a ceramic body to form a base glaze layer;   applying a top glaze material onto the base glaze layer; and   firing the top glaze material in a kiln,   wherein the top glaze material contains a higher weight percent ZnO than the base glaze material.   
     
     
         18 . The method of  claim 17 , comprising firing the base glaze material in a kiln prior to application of the top glaze material. 
     
     
         19 . The method of  claim 17 , comprising air-drying the base glaze material prior to application of the top glaze material. 
     
     
         20 . The method of  claim 17 , comprising applying the base glaze material and/or the top glaze material by spray coating.