| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain an aqueous ink composition capable of suppressing a viscosity change of the ink and excellent in viscosity stabilizing property even on preserving the same for a long period of time by containing a natural polysaccharide and an alkali metal compound. SOLUTION: This aqueous ink composition contains (A) 0.01-4 wt.%, preferably 0.3-2 wt.% natural polysaccharide (preferably a microorganism product- based polysaccharide, especially a xanthane gum, gelan gum, rhamzan gum, or the like), (B) an alkali metal compound (e.g.; sodium hydroxide and a sodium carboxylate) so as to become 1.0×10<-3> -1.0×10<-1> mol, preferably 3.0×10<-3> -5.0×10<-2> mol alkali metal atom based on 100 g ink, and preferably further a metallic powder pigment (e.g.; a brass powder pigment and an aluminum powder pigment).</p> |
