Coating film, and method and apparatus for producing the same

Abstract

A compound represented by a general formula (1) ABXn (where A is a carbon-containing group; B is at least one element selected from Si, Ge, Sn, Ti and Zr; X is a hydrolyzable group; and n is 1, 2 or 3), for example, a chlorosilane compound having a fluorocarbon group, is measured in an amount required for one time application, and dropped from a nozzle on a surface of a substrate having an active hydrogen on the surface, and simultaneously it is rubbed with a coater made of a sponge or a nonwoven fabric, etc. Furthermore, it is rubbed with a coater made of a sponge or a nonwoven fabric, etc. while blowing a dry warm air, and an elimination reaction is caused between the active hydrogen on the surface of the substrate and the hydrolyzable group of the compound. Thus, the compound is covalently bonded to the substrate. The molecules of the is silane compound also are polymerized with one another to be fixed. Thus can be provided a coating film and a method and an apparatus for producing the same, in which: an amount of a liquid required for forming a film is decreased even when the substrate has an irregular shape and a large size; it is not necessary to be concerned for the pot life of a coating solution; the substrate is manipulated easily; and cost is low.

What is claimed is:  
     
         1 . A method for producing a coating film using a compound (1) represented by a general formula (1) ABXn (where A is a carbon-containing group; B is at least one element selected from Si, Ge, Sn, Ti and Zr; X is a hydrolyzable group; and n is 1, 2 or 3) as a raw material, comprising: 
 measuring the compound (1) in an amount required for one time application on a surface of a substrate having an active hydrogen on the surface, and supplying it to the surface of the substrate at each time of application;    in an atmosphere having a water vapor concentration of more than 0.0076 kg/M 3 ,    bringing the compound (1) into contact with the surface of the substrate, causing an elimination reaction between the active hydrogen on the surface of the substrate and the hydrolyzable group in parts of the molecules of the compound (1), thereby covalently bonding the parts of the molecules of the compound (1) to the surface of the substrate, as well as polymerizing parts of the molecules of the compound (1) with one another using water molecules present in the atmosphere.    
     
     
         2 . The method according to  claim 1 , wherein at least one solvent not having an active hydrogen is further added to the compound (1).  
     
     
         3 . The method according to  claim 1 , further comprising washing the substrate and the coating film formed on the substrate after the steps shown in  claim 1 .  
     
     
         4 . The method according to  claim 1 , wherein A in the formula (1) is at least one organic group selected from hydrocarbon groups, fluorocarbon groups, and fluorocarbon-hydrocarbon groups.  
     
     
         5 . The method according to  claim 1 , wherein X in the formula (1) is at least one selected from an isocyanate group, an alkoxyl group, and halogen atoms.  
     
     
         6 . The method according to  claim 1 , wherein the group having an active hydrogen formed on the surface of the substrate is at least one selected from —OH, —NH 2 , >NH and —COOH groups.  
     
     
         7 . The method according to  claim 1 , wherein the chemical reaction is an isocyanic acid elimination reaction, an alcohol elimination reaction, or a halogenohydrogen elimination reaction.  
     
     
         8 . The method according to  claim 1 , wherein the formed coating film has a thickness of at least 1 nm but not more than 0.5 μm.  
     
     
         9 . The method according to  claim 1 , wherein the substrate is at least one selected from glass, metals, metal oxides, ceramics, polymer compounds, and composites thereof.  
     
     
         10 . The method according to  claim 1 , wherein the substrate is a product made from an inorganic oxide as a raw material, and is at least one selected from glass products including glass sheets and mirrors, ceramic products, enameled products, and composites thereof.  
     
     
         11 . The method according to  claim 1 , wherein the water vapor concentration is in a range of 0.077 to 0.0168 kg/m 3 .  
     
     
         12 . The method according to  claim 1 , wherein the compound (1) is brought into contact with the surface of the substrate by impregnating a porous material with the compound (1) and bringing it into contact with the surface of the substrate, and wherein the porous material is at least one selected from resin foams, woven fabrics, knitted fabrics, nonwoven fabrics, and fiber aggregates.  
     
     
         13 . The method according to  claim 1 , wherein means for bringing the compound (1) into contact with the surface of the substrate is rubbing a body impregnated with the compound (1) on the surface of the substrate, while supplying a solution containing the compound (1) on the surface of the substrate.  
     
     
         14 . The method according to  claim 1 , wherein after bringing the compound (1) into contact with the surface of the substrate, a body impregnated with the compound (1) is rubbed on the surface of the substrate, while blowing a dry warm air to the surface of the substrate.  
     
     
         15 . A method for producing a coating film, comprising: applying a coating solution containing a silane-based compound having at least one reactive group selected from at least halogen atoms, an alkoxyl group, and an isocyanate group, to a surface of a substrate having an active hydrogen on the surface; causing an elimination reaction between the active hydrogen on the surface of the substrate and the reactive group of the silane-based compound, thereby covalently bonding the silane-based compound to the surface of the substrate, wherein the method comprises: 
 conveying the substrate into a chamber in which a water vapor concentration in an atmosphere is maintained at more than 0.0076 kg/m 3 ;    measuring a coating solution containing the silane-based compound and at least one solvent not having an active hydrogen in an amount required for one time application (a required amount), and supplying it to a coating device present in the chamber at each time of application;    spreading and rubbing the coating solution uniformly on the surface of the substrate with the coating device;    then changing the atmosphere in the chamber and increasing a concentration of the silane-based compound, thereby accelerating an elimination reaction between the reactive group in parts of the molecules of the silane-based compound and the active hydrogen on the surface of the substrate, and thereby covalently bonding the silane-based compound to the surface of the substrate;    then removing the solvent, and wherein polymerizing parts of the molecules of the silane-based compound with one another using water molecules present in the atmosphere also occurs.    
     
     
         16 . The method according to  claim 15 , wherein when accelerating the elimination reaction, the coating device is operated so that a liquid containing the silane-based compound is further brought into contact with the surface of the substrate.  
     
     
         17 . The method according to  claim 15 , wherein when changing the atmosphere in the chamber and increasing the concentration of the silane-based compound, at least one treatment selected from changing a temperature in the chamber, changing a gas flow rate in the chamber, and changing a temperature of the substrate, is carried out.  
     
     
         18 . The method according to  claim 15 , wherein the solvent not having an active hydrogen is at least one selected from hydrocarbon compounds, siloxane-based compounds, and halogenated hydrocarbons.  
     
     
         19 . The method according to  claim 15 , wherein the coating device comprises a body in a form that makes it impregnated with the coating solution.  
     
     
         20 . The method according to  claim 19 , wherein the body of the coating device in a form that makes it impregnated with the coating solution is a porous material, and wherein the porous material is at least one selected from resin foams, woven fabrics, knitted fabrics, nonwoven fabrics, and fiber aggregates.  
     
     
         21 . The method according to  claim 15 , wherein when spreading the coating solution uniformly on the surface of the substrate using the coating device, the substrate is fixed, and the coating device is rotated or moved in at least one direction selected from a longitudinal direction and a transverse direction.  
     
     
         22 . The method according to  claim 15 , wherein the process of spreading the coating solution uniformly on the surface of the substrate and the process of accelerating the elimination reaction between the reactive group of the silane-based compound in an amount required for one time application and the active hydrogen on the surface of the substrate are carried out in two independent chambers.  
     
     
         23 . The method according to  claim 15 , wherein means for bringing the silane-based compound into contact with the surface of the substrate is rubbing a body impregnated with the silane-based compound on the surface of the substrate, while supplying a solution containing the silane-based compound to the surface of the substrate.  
     
     
         24 . The method according to  claim 15 , wherein after bringing the silane-based compound into contact with the surface of the substrate, a body impregnated with the silane-based compound is rubbed on the surface of the substrate, while blowing a dry warm air to the surface of the substrate.  
     
     
         25 . An apparatus for producing a coating film, comprising: 
 a device for transporting a substrate from an inlet to an outlet in a chamber,    a device for measuring a coating solution containing a silane-based compound and at least one solvent not having an active hydrogen in an amount required for one time application, and supplying it to a coating device present in the chamber at each time of application;    a coating device for applying and spreading the coating solution uniformly, and for accelerating an elimination reaction between the reactive group of the silane-based compound in an amount required for one time application and the active hydrogen on the surface of the substrate;    a device for controlling and maintaining a water vapor concentration in an atmosphere in the chamber at more than 0.0076 kg/m 3 ; and    a device for removing the solvent in the coating solution.    
     
     
         26 . The apparatus according to  claim 25 , wherein the device for transporting the substrate in the chamber is of a belting system or a roller system.  
     
     
         27 . The apparatus according to  claim 25 , wherein the device for supplying the coating solution containing the silane-based compound and the solvent on the surface of the substrate is of a nozzle system or a spray system.  
     
     
         28 . The apparatus according to  claim 25 , wherein the coating device comprises a body in a form that makes it impregnated with the coating solution.  
     
     
         29 . The apparatus according to  claim 25 , wherein the body of the coating device in a form that makes it impregnated with the coating solution is a porous material, and wherein the porous material is at least one selected from resin foams, woven fabrics, knitted fabrics, nonwoven fabrics, and fiber aggregates.  
     
     
         30 . The apparatus according to  claim 25 , wherein the coating device is rotated or moved in a longitudinal direction and/or a transverse direction.  
     
     
         31 . The apparatus according to  claim 25 , wherein a coating device for spreading the coating solution uniformly on the surface of the substrate is different from a coating device for increasing the concentration of the silane-based compound and accelerating the elimination reaction between the reactive group of the silane-based compound at least in an amount required for one time application and the active hydrogen on the surface of the substrate.  
     
     
         32 . The apparatus according to  claim 25 , wherein a chamber in which the coating solution is spread uniformly on the surface of the substrate and a chamber in which the elimination reaction between the reactive group of the silane-based compound in an amount required for one time application and the active hydrogen on the surface of the substrate is accelerated are two independent chambers.  
     
     
         33 . The apparatus according to  claim 25 , wherein the device for bringing the silane-based compound into contact with the surface of the substrate rubs a body impregnated with the silane-based compound on the surface of the substrate, while supplying a solution containing the silane-based compound to the surface of the substrate.  
     
     
         34 . The apparatus according to  claim 25 , wherein after bringing the silane-based compound into contact with the surface of the substrate, a body impregnated with the silane-based compound is rubbed on the surface of the substrate, while blowing a dry warm air to the surface of the substrate.  
     
     
         35 . A coating film characterized in that: 
 the film is transparent;    the film has a thickness of 1 nm to 0.5 μm;    the film has a durability of at least five times for an abrasion resistance test in which a mixture of sugar and soy source (1:1 by weight ratio) is applied, heated at a high temperature of 300° C. for 20 minutes, and cooled, then a fouling baked and adhered can be removed by rubbing with a wet cloth by hand;    parts of the molecules of the film are covalently bonded to a surface of a substrate via at least one element selected from Si, Ge, Sn, Ti and Zr; and    parts of the molecules of the film are polymerized with one another.    
     
     
         36 . The coating film according to  claim 35 , wherein the substrate is at least one selected from glass, metals, metal oxides, ceramics, resins, porcelains, enamel, and composites thereof.