Specific examples of the water soluble organic solvent include: alkyl alcohols having from 1 to 4 carbon atoms such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol and tert-butyl alcohol; amides such as dimethylformamide and dimethylacetamide; one of ketones and ketoalcohols such as acetone and diacetone alcohol; ethers such as tetrahydrofu