The inert material 12B can be natural or synthetic waxes, paraffin waxes, microcrystalline waxes, polyolefin resin waxes such as polyethylene, polypropylene, polybutene, polyethylene oxide, polypropylene oxide and their copolymers such as Elvax??? resin from DuPont; ester waxes, polyurethane waxes, silicone resin waxes.