Method for the production of powder with high tannin content and its use

Abstract

The present invention provides a method of producing powder with a high tannin content, the method including pulverizing a tannin-containing plant such as bark of radiata pine ( Pinus radiata ) and classifying the pulverized material into fine particles having a desired particle size, for example, fine particles having a particle diameter of 100 to 1,000 μm or less, and powder with a high tannin content produced by such a method. The thus obtained powder with a high tannin content exhibits excellent characteristics when used as an adhesive, a binder, etc. for wood materials.

What is claimed is:  
     
         1 . A method for production of powder with a high tannin content, comprising crushing a tannin-containing plant resource and classifying the pulverized plant resource.  
     
     
         2 . A method for production according to  claim 1 , wherein the pulverization is mechanical pulverization.  
     
     
         3 . A method for production according to  claim 2 , wherein the mechanical pulverization is performed by use of an apparatus selected from the group consisting of a hammer mill, a Wiley mill, a ball mill, a roller mill, and a high speed rotary crusher.  
     
     
         4 . A method for production according to  claim 1 , wherein the classification is performed by use of a classifier.  
     
     
         5 . A method for production according to  claim 4 , wherein the classifier is one selected from the group consisting of a screen classifier such as a rotary drum screen and a sieve shaker, and a dry classifier based on gravitational classification, inertial classification and centrifugal classification.  
     
     
         6 . A method for production according to  claim 1 , wherein the powder with a high tannin content which is pulverized and classified has a particle size of 1,000 μm or less.  
     
     
         7 . A method for production according to  claim 1 , wherein the powder with a high tannin content which is pulverized and classified has a particle size of 100 μm or less.  
     
     
         8 . Powder with a high tannin content obtained by a production method according to  claim 1 .  
     
     
         9 . A method of using powder with a high tannin content according to  claim 8  as a substitute for conventional tannin.  
     
     
         10 . A method according to  claim 9 , wherein the powder with a high tannin content is used as a substitute for conventional tannin, in one material selected from the group consisting of an adhesive, a binder, a molded material, a binder for molded materials, a filler, an adhesive enhancer, a health-care food, and a drug.