Coating or plastic compositions specialized for use in producing surfaces which are intended to receive marks, and from which the marks may be readily removed, e.g., blackboards, slates and analogous surfaces.
SEE OR SEARCH CLASS
428, Stock Material or Miscellaneous Articles,
687, for metallic stock material having a special surface feature, e.g., glossy.
434, Education and Demonstration,
425, for devices having erasable surfaces wherein the structure is claimed in combination with special materials used in its construction, and including devices which are merely coated bases.
