Abstract: Expandable thermoplastic resin beads coated with a novel very high frequency energy absorbing material are expanded with microwave energy.

Abstract: An apparatus utilizing cryogenic material to brand the hide of a live animal. The apparatus includes a cup-shaped applicator having a mechanism for defining an aperture of varying configuration in accordance with a desired brand insignia and a mechanism to retain the cryogenic material and to prevent exposure of the animal hide to the cryogenic material except at the aperture. The orifice perimeter is pressed into contact with the hide of the animal to be marked. The cryogenic material retained by the applicator passes through the aperture and contacts an area of animal hide conforming to the configuration of the aperture. The cryogenic material freezes this area of hide long enough to kill the pigment-producing cells (melanocytes) of the hair. The hair in the exposed area is replaced by a growth of white hair, creating a permanent and discernible brand of desired configuration.