Coating agent

Abstract

A coating agent includes a main component containing a polyphenol derivative and a polymerizing agent. The coating agent has a pH of no greater than 9, and the polymerizing agent contains a compound having two or more functional groups selected from the group consisting of an amino group and a mercapto group per molecule.

What is claimed is: 
     
         1 . A coating agent comprising a main component containing a polyphenol derivative and a polymerizing agent, wherein:
 the coating agent has a pH of no greater than 9, and   the polymerizing agent contains a compound having two or more functional groups selected from the group consisting of an amino group and a mercapto group per molecule.   
     
     
         2 . The coating agent according to  claim 1 , wherein the polyphenol derivative is a compound having two or more hydroxyl groups positioned adjacent to one another and bonded together in at least one aromatic ring. 
     
     
         3 . The coating agent according to  claim 1 , wherein the polyphenol derivative is at least one compound selected from the group consisting of catechol and a catechol derivative. 
     
     
         4 . The coating agent according to  claim 3 , wherein the catechol derivative is at least one compound selected from the group consisting of dopamine, dihydroxybenzoic acid and dihydroxyphenylalanine. 
     
     
         5 . The coating agent according to  claim 1 , wherein the compound having two or more functional groups selected from the group consisting of an amino group and a mercapto group per molecule is at least one compound selected from the group consisting of diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, hexamethylenediamine, N-(2-aminoethyl)-1,3-propanediamine, N,N′-1,2-ethanediylbis-1,3-propanediamine, dipropylene-triamine, m-xylylenediamine, p-xylylenediamine, 1,3-bisaminocyclohexylamine, isophoronediamine, 4,4′-methylenebiscyclohexaneamine, 4,4′-methylenebis-(2-methyl-cyclohexaneamine), m-phenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, N-aminoethylpiperazine, 3,9-bis(3-aminopropyl)-2,4,8,10-tetraoxaspiro(5,5)undecane, 4,7-dioxadecane-1,10-diamine, 1-propanamine, 3,3′-(oxybis(2,1-ethanediyloxy))bis (diaminopropylated diethylene glycol), poly(oxy(methyl-1,2-ethanediyl)α-(2-aminomethylethyl)ω-(2-aminomethylethoxy), triethylene glycol diamine, poly(oxy(methyl-1,2-ethanediyl))α,α′-(oxydi-2,1-ethanediyl)bis(ω-aminomethylethoxy)), bis(3-aminopropyl)polytetrahydrofuran, bis(3-aminopropyl) polytetrahydrofuran 750, poly(oxy(methyl-1,2-ethanediyl))α-hydro-ω-(2-aminomethylethoxy) ether, diaminopropyldipropylene glycol having 2-ethyl-2-(hydroxymethyl)-1,3-propanediol, 1,2-ethanedithiol, 1,3-propanedithiol, 1,4-butanedithiol, 1,6-hexanedithiol, 2,2′-thiodiethanethiol, 3,6-dioxa-1,8-octanedithiol, 1,2-benzenedithiol, 1,4-benzenedithiol, toluene-3,4-dithiol, 3-mercaptobutylate and 2-aminoethanedithiol. 
     
     
         6 . The coating agent according to  claim 1 , wherein the molar ratio of the compound having two or more functional groups selected from the group consisting of an amino group and a mercapto group with respect to the polyphenol derivative is no less than 0.1 to no greater than 10. 
     
     
         7 . The coating agent according to  claim 3 , wherein the molar ratio of the compound having two or more functional groups selected from the group consisting of an amino group and a mercapto group with respect to the catechol or catechol derivative is no less than 0.1 to no greater than 10. 
     
     
         8 . The coating agent according to  claim 1 , which contains a pH regulator.