Abstract: A reader-writer apparatus for an optical memory card for reading and/or writing data with respect to the optical memory card having a data storing face, which apparatus includes a card holder including a carriage for carrying and holding the card inserted thereon and transporting the card to a reading or writing position and a feeding mechanism for driving the carriage. The reader/writer in another aspect of the present invention includes an optical waveguide holder holding an optical waveguide, which is connected at a base end thereof to the light emitting and receiving section of a reading head, so that another end of the optical waveguide may oppose a data recording face of the optical memory card. The waveguide holder is moved independently of the movement of the card holder.

Abstract: The present invention relates to a magnetic recording medium prepared by the process comprising (1) coating a magnetic coating composition mainly containing ferromagnetic particles and a binder on a support and (2) irradiating the resulting support with electron beams, wherein the binder contains a compound represented by the following formula, ##STR1## wherein A represents a radical of a hydroxy compound containing at least one isocyanurate ring and at least one (meth)acryloyl group; DI represents a radical of an organic diisocyanate compound; B represents a radical of a polyol having at least two hydroxy groups; C represents a radical of a polybasic acid having at least two carboxy groups; m is a number of 1 to 7; and N is a positive number of 7 or less.

Abstract: A magnetic recording medium is described, comprising a support and a magnetic layer disposed thereon, said magnetic layer containing as its binder component a combination of at least one member of each of the following groups of compounds (1) to (3) that has been exposed to electron beams:(1) vinyl chloride type resin, vinyl acetate type resin, vinyl chloride-vinyl acetate type resin, each containing from 5.times.10.sup.-5 to 2.times.10.sup.-3 equivalents of --CO.sub.2 H groups per gram of copolymer, and nitrocellulose resin;(2) urethane resins and urethane-acrylate oligomers; and(3) compounds containing an isocyanurate ring and at least two groups selected from acryloyl and methacryloyl groups.