Examples of the solvent which can be used in the present invention include aromatic hydrocarbons such as toluene and xylene, ketones such as cyclohexane and methyl ethyl ketone, CELLOSOLVES such as ETHYLCELLOSOLVE, an ester such as ethyl acetate, alcohols such as methanol, ethanol and propanol, acetates such as ETHYLCELLOSOLVE acetate and METHYLCELLOSOLVE acetate, tetrahydrofuran and water.