As the hydrophilic organic solvent which can be used in the concentrated solution composition of the present invention, for example, there are monovalent alcohol (e.g. lower alcohol such as ethanol, n-propyl alcohol, iso-propanol, n-butanol, etc. and diacetone alcohol; monoalkyl ether of diol such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monoethyl ethe