Glaze composition and antifouling ceramic ware
View Patent ↗A glaze composition can be used to provide a glaze layer having excellent antifouling performance and visual beauty. The glaze composition contains a glaze forming material, which has a composition determined such that a baked product obtained by baking the glaze composition comprises 55.0 to 67.0 wt % of SiO 2 ; 8.0 to 11.0 wt % of Al 2 O 3 ; 2.0 to 8.0 wt % of SnO 2 ; 15.0 to 21.0 wt % of a divalent metal oxide; and 4.0 to 6.0 wt % of a monovalent metal oxide, with respect to a total weight of the baked product. When a glaze layer is formed by use of this glaze composition, it resists contamination. Even when a dirt deposits on the glaze layer, the dirt can be easily removed from the glaze layer. In addition, the glaze composition can provide a beautiful semi-opaque glaze layer with luster and a reduction in pore generation amount.
1. A glaze composition containing a glaze forming material, wherein a median diameter after grinding and mixing of said glaze forming material is within a range of 4 to 5 μm, and upon baking, said glaze forming material forming a baked product comprising constituents:
(a) 55.0 to 67.0 wt % of SiO 2 ;
(b) 8.0 to 11.0 wt % of Al 2 O 3 ;
(c) 2.0 to 8.0 wt % of SnO 2 ;
(d) 15.0 to 21.0 wt % of a divalent metal oxide; and
(e) 4.0 to 6.0 wt % of a monovalent metal oxide;
with respect to a total weight of said baked product.
2. The glaze composition as set forth in claim 1 , wherein said glaze forming material comprises, with respect to a total weight of said glaze forming material,
(a) 63.0 to 67.0 wt % of SiO 2 ;
(b) 8.0 to 10.0 wt % of Al 2 O 3 ;
(c) 2.0 to 4.0 wt % of SnO 2 ;
(d) 16.0 to 20.0 wt % of a divalent metal oxide; and
(e) 4.0 to 6.0 wt % of a monovalent metal oxide.
3. The glaze composition as set forth in claim 1 , wherein the constituent (d) comprises, with respect to the total weight of said glaze forming material,
(d1) 10.0 to 12.0 wt % of CaO conversion; and
(d2) 5.0 to 8.0 wt % of ZnO.
4. The glaze composition as set forth in claim 3 , wherein the constituent (d) comprises (d3) 1.0 wt % or less of MgO, with respect to the total weight of said glaze forming material.
5. The glaze composition as set forth in claim 1 , wherein said monovalent metal oxide (e) comprises, with respect to the total weight of said glaze forming material,
(e1) 1.0 wt % or more of Na 2 O; and
(e2) 1.0 wt % or more of K 2 O.
6. The glaze composition as set forth in claim 1 , wherein said glaze forming material contains a frit, which is obtained by vitrifying a material containing at least one of the constituents (a) to (e) and grinding the vitrified material.
7. The glaze composition as set forth in claim 1 , wherein a material containing the constituent (a) of said glaze forming material is a powder having a particle size of 30 pm or less.
8. The glaze composition as set forth in claim 1 , wherein a material containing the constituent (c) of said glaze forming material is a powder having a median diameter of 0.2 to 4.0 μm.
9. The glaze composition as set forth in claim 1 , wherein said glaze forming material is prepared by grinding a material containing at least one of the constituents (a) and (c) to obtain a powder or a slurry, then mixing materials containing the remaining constituents with said powder or said slurry, and grinding a resultant-mixture to obtain a powder of said glaze forming material having a required particle size or a slurry thereof.
10. The glaze composition as set forth in claim 9 , wherein said glaze forming material is prepared by grinding a material containing the constituent (a) to obtain a powder having a median diameter of 5 μm or less or a slurry thereof, then mixing materials containing the remaining constituents (b) to (e) with said powder or said slurry, and grinding a resultant mixture to obtain a powder of said glaze forming material having a required particle size or a slurry thereof.
11. The glaze composition as set forth in claim 9 , wherein said glaze forming material is prepared by grinding a material containing the constituent (c) to obtain a powder having a median diameter of 1.5 to 2 μm or a slurry thereof, then mixing materials containing the remaining constituents (a), (b), (d) and (e) with said powder or said slurry, and grinding a resultant mixture to obtain a powder of said glaze forming material having a required particle size or a slurry thereof.
12. The glaze composition as set forth in claim 9 , wherein said glaze forming material is prepared by grinding materials containing the constituents (a) and (c) to obtain a mixed powder having a median diameter of 5 μm or less or a slurry thereof, then mixing materials containing the remaining constituents (b), (d) and (e) with said mixed powder or said slurry, and grinding a resultant mixture to obtain a powder of said glaze forming material having a required particle size or a slurry thereof.
13. The glaze composition as set forth in claim 9 , wherein said glaze forming material is prepared by grinding a material containing the constituent (a) to obtain a powder having a median diameter of 5 μm or less or a slurry thereof, then mixing materials containing the remaining constituents (b) to (e) with said powder or said slurry, and grinding a resultant mixture to obtain a powder of said glaze forming material having a median diameter of 4 to 5 μm or a slurry thereof.
14. The glaze composition as set forth in claim 9 , wherein said glaze forming material is prepared by grinding a material containing the constituent (c) to obtain a powder having a median diameter of 1.5 to 2 μm or a slurry thereof, then mixing materials containing the remaining constituents (a), (b), (d) and (e) with said powder or said slurry, and grinding a resultant mixture to obtain a powder of said glaze forming material having a median diameter of 4 to 5 μm or a slurry thereof.
15. The glaze composition as set forth in claim 9 , wherein said glaze forming material is prepared by grinding materials containing the constituents (a) and (c) to obtain a mixed powder having a median diameter of 5 μm or less or a slurry thereof, then mixing materials containing the remaining constituents (b), (d) and (e) with said mixed powder or said slurry, and grinding a resultant mixture to obtain a powder of said glaze forming material having a median diameter of 4 to 5 μm or a slurry thereof.
16. The glaze composition as set forth in claim 1 , wherein the materials containing the constituents of said glaze forming material are ground by means of ball milling using alumina balls.
17. The glaze composition as set forth in claim 1 , wherein materials containing the constituents of said glaze forming material are ground by means of ball milling using a pot with an alumina liner and alumina balls.
18. The glaze composition as set forth in claim 1 , comprising a pigment.
19. An antifouling ceramic ware produced by forming a layer of said glaze composition as set forth in claim 1 on a dried base surface of a raw ceramic ware, and baking said layer at a temperature of 1150 to 1250° C. for 8 hours or more to obtain a glaze layer on a baked base surface of the ceramic ware.
20. The antifouling ceramic ware as set forth in claim 19 , wherein an X-ray diffraction profile of said glaze layer has only diffraction peaks resulting from SnO 2 crystal.
21. The antifouling ceramic ware as set forth in claim 19 , wherein an X-ray diffraction profile of said glaze layer has only diffraction peaks resulting from CaSnSiO 5 crystal.
22. The antifouling ceramic ware as set forth in claim 19 , wherein an X-ray ray diffraction profile of said glaze layer has only diffraction peaks resulting from crystals of SnO 2 and CaSnSiO 5 .
23. The antifouling ceramic ware as set forth in claim 19 , wherein a thickness of said glaze layer is within a range of 0.2 to 1.2 mm.