Polysaccharide suspension, method for its preparation, and use thereof

Abstract

The present invention relates to a novel stable colloidal polysaccharide suspension containing α(1→3)-glucan, a cost-effective method for its preparation, and possible uses of these polysaccharide suspensions.

What is claimed is: 
     
         1 . A phase-stable, colloidal polysaccharide suspension characterized in that the polysaccharide consists at least partly of α(1→3)-glucan, that the α(1→3)-glucan was never dried during its preparation, that the suspension was prepared from a press cake having a polysaccharide content between 4 and 80% by weight, preferably between 15 and 45% by weight, and that the polysaccharide concentration of the suspension is between 0.01 and 50% by weight, preferably between 1.0 and 20% by weight. 
     
     
         2 . A suspension as claimed in  claim 1 , characterized in that the α(1→3)-glucan content of the polysaccharide is between 1 and 100% by weight, more preferably between 80 and 100% by weight. 
     
     
         3 . A polysaccharide suspension as claimed in  claim 1 , wherein at least 90% of the α(1→3)-glucan consist of hexose units and at least 50% of the hexose units are linked via α(1→3)-glycosidic bonds. 
     
     
         4 . A polysaccharide suspension as claimed in  claim 1 , containing apart from the polysaccharide material 1 to 200% by weight, related to the polysaccharide quantity, in incorporated additives selected from the group comprising pigments, titanium oxides, especially substoichiometric titanium dioxide, barium sulfate, ion exchangers, polyethylene, polypropylene, polyester, latex, activated carbon, polymeric superabsorbents, and flame retardants. 
     
     
         5 . A method for preparing a polysaccharide suspension, characterized in that
 a. the base material used is a press cake of an initially moist polysaccharide material consisting at least partly of α(1→3)-glucan,   b. the press cake has a solids content between 4 and 80% by weight (related to the entire press cake), preferably between 15 and 45% by weight,   c. the desired polysaccharide concentration is adjusted to between 0.01 and 50% by weight (related to the entire suspension), preferably to between 1.0 and 20% by weight,   d. subsequently comminution with a dispersing unit is carried out.   
     
     
         6 . A method as claimed in  claim 5 , wherein after step d. an additional treatment with a dispersing unit, preferably with a high pressure homogenizer, is carried out. 
     
     
         7 . A method as claimed in  claim 5 , wherein the degree of polymerization of the α(1-→3)-glucan used, expressed as weight average DP w , is between 200 and 2,000, preferably between 400 and 1,000. 
     
     
         8 . A use of the polysaccharide suspension as claimed in  claim 1  for the production of polysaccharide layers. 
     
     
         9 . A use of the polysaccharide suspension as claimed in  claim 1  as a binder for other materials, wherein the adhesive effect is achieved by drying and the formation of hydrogen bonds. 
     
     
         10 . The use of the polysaccharide suspension as claimed in  claim 9 , wherein the other material is a nonwoven material. 
     
     
         11 . The use of the polysaccharide suspension as claimed in  claim 9 , wherein the other material is present in a quantity of 200 to 1000% by weight, related to the polysaccharide quantity. 
     
     
         12 . A use of the polysaccharide suspension as claimed in  claim 1  for the preparation of dried polysaccharide powder. 
     
     
         13 . A dry polysaccharide powder as claimed in  claim 12 , prepared by spray drying. 
     
     
         14 . A use of the polysaccharide suspension as claimed in  claim 1  as a viscosity modifier.