Patent Publication Number: US-2011049394-A1

Title: Ionizing disinfectant surface

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims priority from U.S. Provisional Patent Application Ser. No. 61/238,818, filed Sep. 1, 2009 and incorporated herein by reference in its entirety. 
    
    
     FIELD OF THE INVENTION 
     The present invention generally relates to devices having ionizing radiation, and in particular to such devices which are used for disinfection purposes. 
     BACKGROUND OF THE INVENTION 
     In various practical settings there are work surfaces, such as table-like support surfaces in the food processing industry, or means useful in artificial life support, such as tracheal tubes or feeding tubes, that need to be maintained in a sterile condition and resistant to bacteriological film growth for health and safety reasons but cannot be easily or continuously disinfected. 
     In view of the above, it would be beneficial to have surfaces that reduce the need for disinfectant processes to improve the efficiency of the industrial processes that use such surfaces. 
     SUMMARY OF THE INVENTION 
     In one embodiment, the present invention provides a disinfectant surface, comprising a material layer and alpha-particle emitters embedded in the material layer and located in proximity to a surface of the material layer for emitting alpha particles through the surface for disinfecting any matter contacting the surface. 
     The alpha-particle emitters may be radium. The surface may further comprise a shielding layer formed on the surface to control the range of emission of the alpha particles. The material layer may be ceramic or metal. The material layer may be formed on a substrate. 
     Another embodiment of the present invention provides a method for manufacturing a disinfectant surface, comprising the step of forming a metal or ceramic layer with alpha-particle emitters located in proximity to a surface thereof using liquid chemical deposition. The constituents of the metal or ceramic layer and the alpha-particle emitters may be simultaneously formed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
       The present invention is illustratively shown and described in reference to the accompanying  FIG. 1 , which is a sectional side view of a device constructed with an ionizing disinfectant surface. 
     
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a sectional side view of a piece of material  10  having a material layer  12 , which is optionally formed on a substrate  14 . Embedded within material layer  12  are number alpha-particle emitters  16 , which are each represented by an alpha particle range  18 . Alpha-particle emitters  16  are located either adjacent or sufficiently close to a contact surface  20  of material layer  12  such that the alpha particle range  18  extends past contact surface  20 . This location allows alpha particles to reach anything in contact with contact surface  20  for purposes of disinfection. Alpha-particle emitters  16  are optionally show to be located at different depths with respect to contact surface  20 , but may also be located at approximately the same depth. 
     Surface  20  is optionally shown to have a shielding layer  22 , which creates an alternative contact surface  24 . The alpha particle range  18  is shown to extend slightly beyond alternative contact surface  24 . In this manner, shielding layer  22  may be used to more precisely adjust the distance that the alpha particle range  18  extends beyond the contact surface of the device  10 . It may optional be used for creating a customized surface for a particular purpose. 
     The present invention may be constructed using the Liquid Chemical Deposition methods disclosed in U.S. patent application Ser. No. 12/843,112, filed Jul. 26, 2010 entitled LIQUID CHEMICAL DEPOSITION APPARATUS AND PROCESS AND PRODUCTS THEREFROM, the contents of which are hereby incorporated by reference herein. Using those methods, the material layer  12  may easily be formed of metal or ceramic and applied to a substrate  14 . Alpha-particle emitters  16  may be incorporated into material layer  12  during its formation, and located at any desired depth from the surface  20  of material layer  12 . Any suitable alpha-particle emitters, such as radium, may be used. The intrinsic value for using alpha-particles as the ionizing source to disinfect a surface  24  from bacteriological contamination is that the range (penetration depth) of alpha particles is limited to a couple of millimeters in air, and to shorter distances in solids. As such, alpha-particle radiation is ideal in applications that require a surface to be irradiated, but for adjacent tissue to remain largely unharmed. In this manner, shielding layer  22  may be used to limit alpha-particle penetration to a mere microns past alternative contact surface  24 . 
     The present invention is illustratively described above in reference to the disclosed embodiments. Various modifications and changes may be made to the disclosed embodiments by persons skilled in the art without departing from the scope of the present invention as defined in the appended claims.