The solvents for the aqueous ink include water and a variety of hydrophilic organic solvents, for example, alkyl alcohols of 1 to 4 carbon atoms such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol and isobutyl alcohol; amides such as dimethyl-formamide and dimethylacetamide; ketones or ketone alcohols such as acetone an