Film-forming composition containing tannic acid derivatives

Abstract

The invention provides a film-forming composition containing a tannic acid derivative in which hydrogen atoms in at least some of hydroxyl groups of tannic acid are substituted by a chain hydrocarbon group having 3 to 18 carbon atoms. The film-forming composition of the invention can provide a good enough film on a variety of substrate materials, having improved effects on rust prevention or the like.

1 . A film-forming composition, which contains a tannic acid derivative in which hydrogen atoms in at least some of hydroxyl groups of tannic acid are substituted by a chain hydrocarbon group having 3 to 18 carbon atoms. 
     
     
         2 . A film-forming composition as recited in  claim 1 , wherein said chain hydrocarbon group is an alkyl group. 
     
     
         3 . A film-forming composition as recited in  claim 1 , wherein 10% to 80% of hydroxyl groups of said tannic acid derivative is substituted by said chain hydrocarbon group. 
     
     
         4 . A film-forming composition as recited in  claim 1 , which further includes a solvent and prevails in a solution or paste form. 
     
     
         5 . A film-forming composition as recited in  claim 1 , which further includes water and prevails in an emulsion form. 
     
     
         6 . A film-forming composition as recited in  claim 1 , which further includes an inert gas and prevails in a spray form. 
     
     
         7 . A film-forming composition as recited in  claim 1 , which provides a rust preventive composition. 
     
     
         8 . A film-forming composition as recited in  claim 1 , which provides a composition for disinfection, pasteurization, sterilization or bactericidal activity.