Abstract: A surface processing machine employing a processing tape cartridge for polishing or grinding disks or the like. The machine employs a processing tape cartridge which rotatably accommodates in a casing a pair of reels for the winding of processing tape. The machine comprises a cartridge holder for holding the tape cartridge; a tape drawing mechanism to draw out a portion of the processing tape in the cartridge; a guide roller mechanism for setting and transporting the processing tape on a predetermined path of travel; a work holder mechanism adapted to hold and rotate a work at its machining position; and a tape pressing mechanism for pressing the processing tape against the work.

Abstract: Described herein is a surface treating tape cartridge packaging a surface treating tape in a casing ready for loading the tape on a surface treating machine, and a surface treating machine capable of automatically loading a surface treating tape in position from such a cartridge, the tape cartridge being basically composed of: a casing formed by separably joined upper and lower halves; and a pair of reels carrying a roll of surface treating tape and rotatably accommodated between the upper and lower halves of the casing.

Abstract: A magnetic recording medium employing the ferromagnetic film as the magnetic layer is disclosed in which the non-magnetic metal and/or the non-magnetic metal oxide are diffused into the ferromagnetic film along the direction of film thickness so that the concentration distribution will become substantially uniform. The magnetic recording medium has a high rectangular ratio and a low dispersion of the coercive force.

Abstract: A magnetic recording medium having a non-magnetic substrate on which a first bismuth Bi under layer, a first magnetic metal layer, a compound layer made of the magnetic metal, a second bismuth Bi under layer and a second magnetic metal layer are sequentially formed in this order.

Abstract: A magnetic recording medium is disclosed which includes a non-magnetic substrate, a first layer made of bismuth formed on the substrate in a discontinuous island shape, and a ferromagnetic metal layer formed over the first layer and the substrates and also a magnetic recording medium is disclosed which includes a non-magnetic substrate, a first layer formed continuously covering the substrate made of amorphous silicon and/or silicon compound, a second layer made of bismuth formed on the substrate in a discontinuous island shape and a ferromagnetic metal layer formed over the first and second layers.

Abstract: A magnetic recording medium having a non-magnetic substrate, a bismuth layer of less than 100 .ANG. thick formed on one major surface of the non-magnetic substrate and a magnetic metal thin film formed on the bismuth layer.

Abstract: A method of preparing gamma ferric hydroxyoxide in which ferrous ions are reacted in an alkaline solution to produce a suspension of ferric hydroxide, the resulting suspension is treated with an oxidizing gas in a first oxidizing step at a relatively high oxidation rate, sufficient to cause nucleation of gamma ferric hydroxyoxide to occur, and then the oxidation rate is reduced in a second oxidizing step to cause crystal growth to occur on the nuclei formed in the first oxidizing step. The resulting product has magnetic and physical characteristics making it extremely suitable for use in the manufacture of magnetic recording media.