Abstract: A holographic article and method for forming permits the party producing the final document to print the holographic image directly on the final document thereby permitting such party to retain and maintain control of its own embossing shim on which the hologram has been formed and which is utilized for embossing the holographic image on the document. A film upon which a holographic image can be directly stamped upon the final document includes a layer of metal having a thickness in the range of 20 millimicrons to 100 millimicrons, a lacquer coating having a thickness in the range of 0.5 microns to 3 microns and a heat activatible adhesive. The metal layer lacquer coating and heat activatible adhesive are caused to be adhered to the substrate forming the final document during a stamping operation which releases said metal layer, lacquer coating and heat activatible adhesive from a plastic carrier film to which had initially been applied.

Abstract: The invention relates to material silicon nitride powder used for production of silicon nitride ceramics products. Provided herein is a material powder which can offer a compact having a homogeneous packing structure of the powder with good reproducibility and also to provide a method for producing the same. According to the method, a silicon nitride powder is heat treated in two-stage processing, one stage in an inert gas or reducing atmosphere at 100.degree. C.-1000.degree. C. for 5-600 min., and another stage in an oxidizing atmosphere at 300.degree. C.-1200.degree. C. for 5-600 min. As a result of this treatment, a silicon nitride powder is obtained in which its powder particles are crystalline in their interior and are coated with an amorphous layer having a 1-10 nm surface thickness and composed mainly of Si, N, O, and H, an atomic number ratio of oxygen to nitrogen (O/N) of the surface layer being within a range of 0.1-2.0.