Gauge lens with embedded anti-fog film and method of making the same

Abstract

The gauge lens with anti-fog film includes a substantially planar transparent lens substrate having an outer surface and an inner surface and a thin film possessing anti-fog properties adjacent and substantially covering the inner surface of the lens substrate to provide a low angle of contact for water and moisture. The anti-fog film is bonded to the lens substrate during the molding process that produces the lens substrate shape. The anti-fog film comprises a hydrophilic material or is coated with a hydrophilic coating. In addition to the anti-fog film, in another embodiment, the outer surface of the lens substrate has a hard coat film adjacent and substantially covering the outer surface of said lens. The materials for the lens substrate, anti-fog film, and hard coat film are selected based on the application, performance, and stability of the gauge lens in the environment that it is operated.

1 . An anti-fog gauge lens, comprising: 
 a substantially planar transparent lens substrate having an outer surface and an inner surface; and    a film having a first surface and a second surface, said first surface of said film is adjacent and substantially covering said inner surface of said lens, and said second surface having hydrophilic properties for preventing moisture condensation from forming on said second surface of said film.    
     
     
         2 . The anti-fog gauge lens of  claim 1 , wherein said first surface of said film is bonded to said inner surface of said lens during the molding process of said lens.  
     
     
         3 . The anti-fog gauge lens of  claim 1 , wherein said lens substrate comprises a thermoplastic material.  
     
     
         4 . The anti-fog gauge lens of  claim 1 , wherein said lens substrate comprises a polymer selected from the group consisting of polyvinyl chloride, nylon, fluorocarbons, linear polyethylene, polyethylenes, polyethylene terephthalate, polyurethane prepolymer, polyesters, polycarbonates, polystyrene, polypropylene, cellulosic resins, acrylic resins, acrylates, methyl methacrylate, polymethyl-methacrylate, epoxides, epoxies, plastics, and polymers or copolymers of acrylic acid, methacrylic acid, esters of these acids, and acrylonitrile.  
     
     
         5 . The anti-fog gauge lens of  claim 1 , wherein said film comprises a material selected from linear polyethylene, polyethylenes, plastics, polycarbonates, polyethylene terephthalate, and acrylics.  
     
     
         6 . The anti-fog gauge lens of  claim 5 , wherein said second surface of said film is coated with a hydrophilic coating.  
     
     
         7 . The anti-fog gauge lens of  claim 1 , wherein said lens substrate is between 0.1 to about 10 millimeters in thickness.  
     
     
         8 . The anti-fog gauge lens of  claim 1 , wherein said lens substrate is between 1 to about 3 millimeters in thickness.  
     
     
         9 . The anti-fog gauge lens of  claim 1 , wherein said film is between 0.002 to about 0.020 inches in thickness.  
     
     
         10 . The anti-fog gauge lens of  claim 1 , wherein said film is between 0.007 to about 0.010 inches in thickness.  
     
     
         11 . The anti-fog gauge lens of  claim 1 , further comprising a hard coat film having a first surface and a second surface, said first surface adjacent and substantially covering said outer surface of said lens.  
     
     
         12 . The anti-fog gauge lens of  claim 11 , wherein said first surface of said hard coat film is bonded to said outer surface of said lens during the molding process of said lens.  
     
     
         13 . The anti-fog gauge lens of  claim 12 , wherein said hard coat film comprises a material selected from the group consisting of polyvinyl chloride, fluorocarbons, polyethylenes, polyethylene terephthalate, polyurethane prepolymer, polycarbonates, polystyrene, polypropylene, cellulosic resins, acrylic resins, acrylates, methyl methacrylate, polymethyl-methacrylate, epoxides, epoxies, plastics, and polymers or copolymers of acrylic acid, methacrylic acid, esters of these acids, and acrylonitrile.  
     
     
         14 . A lens having anti-fog properties for use with a gauge body, comprising: 
 a substantially planar transparent lens substrate terminating at its periphery in a sidewall, said lens substrate and said sidewall having an outer surface and an inner surface; and    a film having a first surface and a second surface, said first surface of said film is adjacent and substantially covering said inner surface of said lens, and said second surface providing a water wettability of less than about 10 in terms of contact angle for preventing moisture condensation from forming on said second surface of said film.    
     
     
         15 . The lens of  claim 14 , wherein said first surface of said film is bonded to said inner surface of said lens during the molding process of said lens.  
     
     
         16 . The lens of  claim 14 , wherein said first surface of said film covers a portion of said inner surface of said sidewall.  
     
     
         17 . The lens of  claim 16 , wherein said first surface of said film is bonded to a portion of said inner surface of said sidewall during the molding process of said lens.  
     
     
         18 . The lens of  claim 14 , wherein said lens substrate comprises a thermoplastic material.  
     
     
         19 . The lens of  claim 14 , wherein said lens substrate comprises a polymer selected from the group consisting of polyvinyl chloride, nylon, fluorocarbons, linear polyethylene, polyethylenes, polyethylene terephthalate, polyurethane prepolymer, polyesters, polycarbonates, polystyrene, polypropylene, cellulosic resins, acrylic resins, acrylates, methyl methacrylate, polymethyl-methacrylate, epoxides, epoxies, plastics, and polymers or copolymers of acrylic acid, methacrylic acid, esters of these acids, and acrylonitrile.  
     
     
         20 . The lens of  claim 14 , wherein said film comprises a material selected from linear polyethylene, polyethylenes, plastics, polycarbonates, polyethylene terephthalate, and acrylics.  
     
     
         21 . The lens of  claim 14 , wherein said second surface of said film is coated with a hydrophilic coating.  
     
     
         22 . The lens of  claim 14 , wherein said second surface of said film is coated with a hydrophobic coating.  
     
     
         23 . The lens of  claim 14 , further comprising a hard coat film having a first surface and a second surface, said first surface adjacent and substantially covering said outer surface of said lens.  
     
     
         24 . The lens of  claim 23 , wherein said hard coat film comprises a material selected from the group consisting of polyvinyl chloride, fluorocarbons, polyethylenes, polyethylene terephthalate, polyurethane prepolymer, polycarbonates, polystyrene, polypropylene, cellulosic resins, acrylic resins, acrylates, methyl methacrylate, polymethyl-methacrylate, epoxides, epoxies, plastics, and polymers or copolymers of acrylic acid, methacrylic acid, esters of these acids, and acrylonitrile.  
     
     
         25 . A method for manufacturing an anti-fog gauge lens having a substantially planar transparent lens substrate having an outer surface and an inner surface, and a film having a first surface and a second surface, in an injection mold comprising a gate, a core side for molding said inner surface of said lens, and a cavity side for molding said outer surface of said lens; said method comprising: 
 cutting said film to substantially fit the shape of said inner surface of said lens;    positioning said second surface of said film on said core side of said mold;    preparing said mold for accepting a resin material comprising said lens substrate;    injecting said resin material into said mold;    cooling said mold; and    removing said anti-fog gauge lens from said mold.    
     
     
         26 . The method of  claim 25 , wherein said positioning further comprises: 
 positioning said film between a peripheral rim on said core side of said mold.    
     
     
         27 . The method of  claim 25 , further comprising: 
 forming said film to fit snugly onto the core side of said mold.    
     
     
         28 . The method of  claim 25 , wherein said preparing said mold further comprises: 
 heating said mold to a temperature to facilitate the complete charging of said mold by said resin material.    
     
     
         29 . A method for manufacturing an anti-fog gauge lens having a substantially planar transparent lens substrate having an outer surface and an inner surface, a film having a first surface and a second surface, and a hard coat film having a first surface and a second surface, in an injection mold comprising a gate, a core side for molding said inner surface of said lens, and a cavity side for molding said outer surface of said lens; said method comprising: 
 cutting said film to substantially fit the shape of said inner surface of said lens and said hard coat film to substantially fit the shape of said outer surface of said lens;    positioning said second surface of said film on said core side of said mold and said second surface of said hard coat film on said cavity side of said mold;    preparing said mold for accepting a resin material comprising said lens substrate;    injecting said resin material into said mold;    cooling said mold; and    removing said anti-fog gauge lens from said mold.    
     
     
         30 . The method of  claim 29 , wherein said positioning further comprises: 
 positioning said film between a peripheral rim on said core side of said mold.    
     
     
         31 . The method of  claim 29 , further comprising: 
 forming said film to fit snugly onto the core side of said mold and said hard coat film to fit snugly into said cavity side of said mold.    
     
     
         32 . The method of  claim 29 , wherein said preparing said mold further comprises: 
 heating said mold to a temperature to facilitate the complete charging of said mold by said resin material.