Antibacterial material and antibacterial film and antibacterial member using the same

Abstract

In one embodiment, an antibacterial material includes at least one microparticles selected from tungsten oxide microparticles and tungsten oxide complex microparticles. The microparticles, which are undergone a test to evaluate viable cell count by inoculating in a test piece, to which the microparticles are adhered in a range of 0.02 mg/cm 2 or more and 40 mg/cm 2 or less, at least one bacterium selected from among Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa , methicillin-resistant Staphylococcus aureus , and enterohemorrhagic Escherichia coli , and storing for 24 hours, have an antibacterial activity value R of 0.1 or more expressed by the following: R =log( B 1 /C 1 ) where, B 1 denotes an average value (number) of viable cell count after storing an untreated test piece for 24 hours, and C 1 denotes an average value (number) of viable cell count after storing the test piece on which the microparticles are coated for 24 hours.

What is claimed is: 
     
         1 . An antibacterial material comprising at least one microparticles selected from tungsten oxide microparticles and tungsten oxide complex microparticles,
 wherein the microparticles, which are undergone an antibacterial property evaluation test to evaluate viable cell count by inoculating in a test piece, to which the microparticles are adhered in a range of 0.02 mg/cm 2  or more and 40 mg/cm 2  or less, at least one bacterium selected from among  Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa , methicillin-resistant  Staphylococcus aureus , and enterohemorrhagic  Escherichia coli , and storing for 24 hours by a method according to Antimicrobial products—Test for antimicrobial activity of JIS-Z-2801 (2000), have an antibacterial activity value R of 0.1 or more expressed by the following:
     R =log( B   1   /C   1 ) 
   
       where, B 1  denotes an average value (number) of viable cell count after storing an untreated test piece for 24 hours, and C 1  denotes an average value (number) of viable cell count after storing the test piece on which the microparticles are coated for 24 hours). 
     
     
         2 . The antibacterial material according to  claim 1 ,
 wherein the microparticles, which are undergone the antibacterial property evaluation test in a dark place, have an antibacterial activity value R D  of 0.1 or more expressed by the following:
     R   D =log( B   D   /C   D ) 
   
       where, B D  denotes an average value (number) of viable cell count after storing an untreated test piece in a dark place for 24 hours, and C D  denotes an average value (number) of viable cell count after storing the test piece on which the microparticles are coated in a dark place for 24 hours. 
     
     
         3 . The antibacterial material according to  claim 1 ,
 wherein the antibacterial activity value R of the microparticles is 1 or more.   
     
     
         4 . The antibacterial material according to  claim 2 ,
 wherein the antibacterial activity value R D  of the microparticles is 1 or more.   
     
     
         5 . The antibacterial material according to  claim 1 ,
 wherein the microparticles have an average primary particle size (D50) in a range of 1 nm or more and 200 nm or less.   
     
     
         6 . The antibacterial material according to  claim 1 ,
 wherein the microparticles have a BET specific surface area in a range of 4.1 m 2 /g or more and 820 m 2 /g or less.   
     
     
         7 . The antibacterial material according to  claim 1 ,
 wherein the microparticles measured by an X-ray diffraction method have 2θ with a first peak, a second peak and a third peak in a range of 22.5 degrees or more and 25 degrees or less.   
     
     
         8 . The antibacterial material according to  claim 1 ,
 wherein the microparticles, which are undergone the antibacterial property evaluation test using a white fluorescent lamp and an UV cut filter with visible light having a wavelength of 380 nm or more and an illuminance of 6000 lx irradiated to the test piece, have an antibacterial activity value R L  of 1.0 or more expressed by the following:
     R   L =log( B   L   /C   L ) 
   
       where, B L  denotes an average value (number) of viable cell count after storing an untreated test piece under the visible light for 24 hours, and C L  denotes an average value (number) of viable cell count after storing the test piece on which the microparticles are coated under the visible light for 24 hours. 
     
     
         9 . The antibacterial material according to  claim 1 ,
 wherein the tungsten oxide complex contains a transition metal element in a range of 0.01 mass % or more and 50 mass % or less.   
     
     
         10 . The antibacterial material according to  claim 1 ,
 wherein the tungsten oxide complex contains at least one metal element selected from among Ti, Zr, Mn, Fe, Pd, Pt, Cu, Ag, Zn, Al and Ce in a range of 0.001 mass % or more and 50 mass % or less.   
     
     
         11 . The antibacterial material according to  claim 1 ,
 wherein the tungsten oxide complex contains at least one metal element selected from among Cu, Ag and Zn in a range of 0.001 mass % or more and 1 mass % or less.   
     
     
         12 . The antibacterial material according to  claim 10 ,
 wherein the metal element is contained in the tungsten oxide complex in at least one form selected from among a single element, a compound and a complex compound with tungsten oxide.   
     
     
         13 . An antibacterial film comprising the antibacterial material according to  claim 1 . 
     
     
         14 . The antibacterial film according to  claim 13 ,
 wherein the antibacterial film contains an inorganic binder in a range of 5 mass % or more and 95 mass % or less.   
     
     
         15 . The antibacterial film according to  claim 13 ,
 wherein a thickness of the antibacterial film is in a range of 2 nm or more and 1000 nm or less.   
     
     
         16 . An antibacterial member comprising the antibacterial material according to  claim 1 . 
     
     
         17 . An antibacterial member comprising the antibacterial film according to  claim 13 . 
     
     
         18 . The antibacterial member according to  claim 17 ,
 wherein the antibacterial member is used under irradiation of visible light having an illuminance of 1000 lx or less.   
     
     
         19 . The antibacterial member according to  claim 18 ,
 wherein the antibacterial member is used in a dark place.   
     
     
         20 . The antibacterial member according to  claim 19 ,
 wherein the antibacterial member is used as a member exhibiting antibacterial performance to at least one bacterium selected from among  Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa , methicillin-resistant  Staphylococcus aureus , and enterohemorrhagic  Escherichia coli.