Abstract: Cellulose diester films that include a cellulose diester; a plasticizer; a colorant; and an opacity additive may be useful for playing cards. In some instances, forming cellulose diester films may include preparing a dope that comprises a cellulose diester, a plasticizer, and a solvent; introducing a colorant and an opacity additive into the dope to yield a casting dope; and casting the casting dope into a cellulose diester film. Playing cards may then be produced by methods including, for example, cutting the cellulose diester film and printing on the cellulose diester film.