Water-repellent film-coated articles, water-repellent film-coating liquid composition and process for preparation of water-repellent film-coated articles

Abstract

There are provided articles coated with high-performance water-repellent films with high hardness that can withstand outdoor use, which are water-repellent film-coated articles that comprise a substrate and a water-repellent film composed mainly of silicon oxide and having a water-repellent group coated on the surface of the substrate, and are characterized by containing at least one type of metal oxide selected from the group consisting of magnesium oxide, calcium oxide, strontium oxide and boron oxide, as well as a process for preparation of such water-repellent film-coated articles at a high rate of productivity and a coating liquid composition for preparation of such water-repellent film-coated articles.

What is claimed is:  
     
         1 . A water-repellent film-coated article comprising 
 a substrate and    a water-repellent film, composed of silicon oxide and at least one of metal oxide selected from the group consisting of magnesium oxide, calcium oxide, strontium oxide and boron oxide and having a water-repellent group, coated on the surface of the substrate.    
     
     
         2 . A water-repellent film-coated article according to  claim 1 , wherein said water-repellent film contains 
 silicon oxide at 70-99 mole percent (based on SiO 2 ),    at least one of metal oxide selected from the group consisting of magnesium oxide, calcium oxide, strontium oxide and boron oxide at a total of 1-30 mole percent (based on MgO, CaO, SrO and BO 3/2 ), and    a water-repellent group at 0.01-20 wt %.    
     
     
         3 . A water-repellent film-coated article according to  claim 2 , wherein said water-repellent film further contains, in terms of mole percent, at least one of metal oxide selected from the group consisting of zirconium oxide, aluminum oxide, gallium oxide, indium oxide, scandium oxide, yttrium oxide, lanthanum oxide, cerium oxide, cobalt oxide, iron oxide, nickel oxide, copper oxide and zinc oxide at 0.5-5%, based on ZrO 2 , AlO 3/2 , GaO 3/2 , InO 3/2 , ScO 3/2 , YO 3/2 , LaO 3/2 , CeO 3/2 , CoO, FeO 3/2 , NiO 2 , CuO and ZnO.  
     
     
         4 . A water-repellent film-coated article according to  claim 1 , wherein said water-repellent film contains 
 silicon oxide at 70-98 mole percent (based on SiO 2 ),    magnesium oxide and/or calcium oxide at 1-29 mole percent (based on MgO and CaO),    boron oxide and/or zirconium oxide at 1-29 mole percent (based on BO 3/2  and ZrO 2 ) and    a water-repellent group at 0.01-20 wt %.    
     
     
         5 . A water-repellent film-coated article according to  claim 4 , wherein said water-repellent film further contains, in terms of mole percent, at least one of metal oxide selected from the group consisting of aluminum oxide, gallium oxide, indium oxide, scandium oxide, yttrium oxide, lanthanum oxide, cerium oxide, cobalt oxide, iron oxide, nickel oxide, copper oxide and zinc oxide at 0.5-5%, based on AlO 3/2 , GaO 3/2 , InO 3/2 , ScO 3/2 , YO 3/2 , LaO 3/2 , CeO 3/2 , CoO, FeO 3/2 , NiO 2 , CuO and ZnO.  
     
     
         6 . A water-repellent film-coated article according to any one of  claims 1  to  5 , wherein said water-repellent group is an alkyl group or fluoroalkyl group.  
     
     
         7 . A water-repellent film-coating composition containing 
 (A) a thoroughly hydrolyzable silane compound,    (B) a silane compound with a water-repellent group,    (C) an acid and    (D) a compound of at least one of metal selected from the group consisting of magnesium, calcium, strontium and boron.    
     
     
         8 . A water-repellent film-coating composition according to  claim 7  which contains said silane compound (A) at 0.01-2 wt % based on SiO 2 , said silane compound (B) at 0.00001-0.15 wt % based on SiO 2 , said acid at 0.001-3 N, water at 0-5 wt % and said compound (D) at a molar ratio of 0.01-0.4, based on MgO, CaO, SrO and BO 3/2 , with respect to said silane compound (A).  
     
     
         9 . A water-repellent film-coating composition according to  claim 7  or  8  which contains an alcohol as a solvent.  
     
     
         10 . A water-repellent film-coating composition containing 
 (A) a thoroughly hydrolyzable silane compound or its hydrolysate at 0.01-2 wt % (based on SiO 2 ),    (B) a silane compound with a water-repellent group at 0.00001-0.15 wt % (based on SiO 2 ),    (C) an acid at 0.001-3 N,    (D-1) a magnesium and/or calcium compound at a molar ratio of 0.01-0.4, based on MgO and CaO, with respect to said silane compound (A) (based on SiO 2 ),    (D-2) a boron and/or zirconium compound at a molar ratio of 0.01-0.4, based on BO 3/2  and ZrO 2 , with respect to said silane compound (A) (based on SiO 2 ),    (E) a compound of at least one of metal selected from the group consisting of cobalt, iron, nickel, copper, aluminum, gallium, indium, scandium, yttrium, lanthanum, cerium and zinc at a molar ratio of 0-0.4, based on CoO, FeO 3/2 , NiO 2 , CuO, AlO 3/2 , GaO 3/2 , InO 3/2 , ScO 3/2 , YO 3/2 , LaO 3/2 , CeO 3/2  and ZnO, with respect to said silane compound (A) (based on SiO 2 ), and    (F) water at 0-20 wt %.    
     
     
         11 . A water-repellent film-coating composition according to  claim 10  which contains an alcohol as the solvent.  
     
     
         12 . A water-repellent film-coating composition according to any one of  claims 7  to  11 , wherein said silane compound (A) is a tetraalkoxysilane or tetrachlorosilane.  
     
     
         13 . A water-repellent film-coating composition according to any one of  claims 7  to  12 , wherein said acid is hydrochloric acid, nitric acid, acetic acid, formic acid or trifluoroacetic acid.  
     
     
         14 . A process for preparation of a water-repellent film-coated article, characterized by applying a water-repellent film-coating composition according to any one of  claims 7  to  13  onto a substrate surface and drying it.  
     
     
         15 . A process for preparation of a water-repellent film-coated article according to  claim 14 , wherein said drying is carried out at room temperature.  
     
     
         16 . A process for preparation of a water-repellent film-coated article according to  claim 14  or  15 , wherein said drying is carried out in an atmosphere at 40% relative humidity or lower.  
     
     
         17 . A process for preparation of a water-repellent film-coated article according to any one of  claims 14  to  16 , wherein said drying is followed by heating at a temperature of from room temperature up to 300° C.  
     
     
         18 . A process for preparation of a water-repellent film-coated article according to any one of  claims 14  to  16 , wherein said drying is followed by heating at a temperature of from room temperature up to 150° C.