TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The porous base material has a pore size of 0.01-50 mu m, porosity of 10-95 %. The particle size of the inorganic material is 0.01-10 mu m. The weight ratio of the binder and the inorganic material is 50:50-99:1. The porous coating layer has a pore size of 0.01-10 mu m, porosity of 5-95 %, and thickness of the porous coating layer of 0.01-20 mu m.    TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The acrylic copolymer includes hydroxide group and carboxylic acid group consisting of an amine functional group and an amide functional group containing a first functional group and a second functional group. The acrylic copolymer is derived from monomers having the first functional group and the second functional group, where a repeating unit is derived from the monomer. The monomer having first functional group includes 1-(meth)acrylic acid, 2-(meth)acryloyloxy acetic acid, 3-(meth)acryloyloxy propyl acid, 4-(meth)acryloyloxy butyric acid, acrylic acid dimer, itaconic acid, maleic acid, maleic anhydride, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, 2-hydroxy ethylene glycol (meth) acrylate and 2-hydroxypropylene glycol (meth)acrylate. The monomer having second functional group consists of 2 -(((butoxy amino) carbonyl) oxy)ethyl(meth)acrylate, 2-(diethylamino) ethyl (meth) acrylate, 2-(dimethylamino) ethyl (meth) acrylate, 3-(diethylamino) propyl (meth) acrylate, 3-(dimethylamino) propyl (meth) acrylate, methyl 2-aceto amido (meth) acrylate, 2-(meth) acrylamidoglycolic acid, 2-(meth) acryl amide-2-methyl-1-propansulfonic acid, (3-(meth) acrylamido propyl) trimethyl ammonium chloride, N-(meth) acryloyl amido-ethoxyethanol, 3-(meth) acryloylamino-1-propanol, N-(butoxymethyl) (meth)acrylo amide, N-tert-butyl (meth)acrylamide, diacetone (meth)acrylamide, N,N-dimethyl (meth)acrylamide, N-(isobutoxymethyl) acrylamide, N-(isopropyl) (meth)acrylamide, 1-(meth) acrylamide, N-phenyl (meth) acrylamide, N-(tris (hydroxymethyl) methyl) (meth) acrylamide, N-N'-(1,3-phenylene) dimaleimide and N-N'-(1,4-phenylene) dimaleimide. The polyvinylidene fluoride copolymer includes N-N'-(1,2-dihydroxy ethylene) bis acrylamide. The acrylic copolymer includes ethyl acrylate-acrylic acid-N,N-dimethylacrylamide copolymer and ethyl acrylate-acrylic acid-2-(dimethylamino) ethyl acrylate. The polyvinylidene fluoride copolymer includes polyvinylidene fluoride-co-hexafluoropropylene, polyvinylidene fluoride-co-trichloroethylene, polyvinylidene fluoride-co-tetrafluoroethylene, polyvinylidene fluoride-co-trifluoroethylene and polyvinylidene fluoride-co-trifluorochloroethylene. The porous base material is made of polyolefin-group porous film. The porous base material is formed by mixing nonwoven fabric and polymers consisting of polyethyleneterephthalate, polybutyleneterephthalate, polyester, polyacetal, polyamide, polycarbonate, polyimide, polyetheretherketone, polyaryletherketone, polyetherimide, polyamideimide, polybenzimidazole, polyethersulfone, polyphenyleneoxide, cyclic olefin copolymer, polyphenylenesulfide and polyethylenenaphthalene. EXAMPLE - No suitable example given.