bond nonwoven fabric a spun bond nonwoven fabric a chemical bond nonwoven fabric an air laid nonwoven fabric and a mixture thereof may be used as the porous substrate 20 further a cloth styrofoam paper or a mesh that has pores may be used as the porous substrate 20 in addition to the nonwoven fabric the porous substrate 20 may have a black or different color and a method of coating the pigment may employ gravure printing coating and may also employ a dope dye scheme the porous nanoweb 10 is formed into a shape having a plurality of pores 12 by making ultra fine fiber strands 14 by electrospinning the polymer material to which the black or different color pigment is added and accumulating the ultra fine fiber strands the polymer material used to make the porous nanoweb 10 in the present invention may be a resin that may be dissolved in an organic solvent for electrospinning and that may be capable of forming nanofibers by electrospinning but are not specifically limited thereto for example the polymer materials used in the present invention may be polyvinylidene fluoride pvdf poly vinylidene fluoride co hexafluoropropylene a perfluoropolymer polyvinyl chloride polyvinylidene chloride or a copolymer thereof a polyethylene glycol derivative containing polyethylene glycol dialkylether and polyethylene glycol dialkylester poly oxymethylene oligo oxyethylene polyoxide containing polyethylene oxide and polypropylene oxide polyvinyl acetate poly vinyl pyrrolidone vinyl acetate polystyrene and.