Abstract: A particulate magnetic recording media wherein the magnetic particles are substantially spherical. The spherical particle shape makes possible a media which is magnetically isotropic, well dispersed and low in noise, and free of magnetically inferior broken particles.

Abstract: A plastic structure comprising:a plastic media, such as a plastic card; anda thin film amorphous inorganic or DLC coating on the plastic media, the coating being hard, transparent or semi-transparent, and wear resistant.

Abstract: An identification card comprising a card stock comprising a plastic material having magnetic particles uniformly dispersed throughout, the card stock also having an image-receiving layer located on the outermost surface of at least one side of the card stock, the image-receiving layer comprising a polycarbonate having a Tg of less than about 80.degree. C.

Abstract: There is disclosed a magnetic head particularly suited for high frequency applications. The head has a ceramic body of a new ceramic material which provides longer service life together with a high level of operating efficiency and cost effectiveness. The head includes a core of magnetic material, such as thin layers of the metal FeAlSi, bonded to pieces of the ceramic material. The coefficients of thermal expansion of the ceramic and the core are suitably matched to permit wide temperature excursions (e.g., 500.degree. C.) during manufacture of the head. The ceramic is a matrix of a material such as a metal titanate in which are distributed hard inclusions such as a metal oxide which are tightly bound to the matrix to preclude pull out of the inclusions during machining of the ceramic. The wear resistance and other characteristics of the magnetic head are greatly improved compared to a comparable head made with manganese nickel oxide ceramic, for example.

Abstract: There are described a glass composition and a magnetic head containing the same, wherein the glass composition comprises an oxide of an alkali metal or alkaline earth, and at least one non-alkali metal oxide in an amount sufficient to provide a coefficient of thermal expansion of 80-170.times.10.sup.-7 .degree. C..sup.-1, the composition featuring from 5-15 mole % Al.sub.2 O.sub.3 and an amount of a compatible glass former sufficient to insure the Al.sub.2 O.sub.3 is soluble in the composition.