A composition of matter includes a flexible substrate and a coating disposed on the substrate. The coating comprises about 10-60 wt-% of a waxy compound and about 90-40 wt-% of a diluent. The coating forms a stable liquid mixture at a temperature between about 35° C. and about 100° C., has a liquefaction temperature of at least about 30° C., and has a contact angle with a flat surface of the substrate of less than about 35° when measured at a temperature of 60° C.