DENNISON MANUFACTURING <DSN> TO SELL PAPER UNIT Dennison Manufacturing Co said it has signed a letter of intent to sell its Dunn Paper Co subsidiary to James River Corp <JR> for an undisclosed amount of cash, resulting in a first quarter charge against earnings. The company saiud the loss on the sale may be partly reduced by contingent payments over the next five years and will in the first quarter be more than offset by the gain from the previously-announced sale of its Hygeia Sciences Inc shares. Dunn had sales last year of about 65 mln dlrs. In Richmond, Va., James River said closing is expected by the end of April, subject to approval by both boards and on the reaching of satisfactory labor agreements.