Abstract: A beam recorder comprises a beam generator, a deflector for deflecting the beam to scan the beam, and a light intensity control unit for controlling a light intensity of the beam. The deflection has a plurality of deflection planes to which the beam is directed, and at least one of the deflection planes in a non-scan plane. The light intensity control is effected by utilizing a period in which the beam is directed to the non-scan plane.

Abstract: A card including a rotatory system optical recording medium, comprises a rotatory system optical recording medium, a case body having a holding space which holds said optical recording medium freely detachably and a protective cover which protects the surface of said optical recording medium held on said case body, said case body being provided with an opening means for the protective cover so that said optical recording medium can be detached from said holding space.A recording and/or reproducing device for a card including a rotatory system optical recording medium comprises a means for releasing from a case body a rotatory system optical recording medium held on the case body having a protective cover by utilizing the opening formed by removal of the protective cover, a means for rotating said optical recording medium and a means for returning said optical recording medium to the holding space after recording and/or reproduction.

Abstract: A chlorinated rubber having a chlorine content of 10 to 45% by weight based on the weight of the chlorinated rubber and a Mooney viscosity, ML.sub.1+4 (121.degree. C.), of 10 to 190 is obtained by chlorinating an ethylene/alpha-olefin/non-conjugated diene copolymer rubber containing 5-vinyl-2-norbornene as the non-conjugated diene. The chlorinated rubber has excellent processability in roll milling, extrusion, etc.

Abstract: An optical recording carrier for recording and/or reading information by irradiation with light comprises a conductive material layer capable of being electrostatically charged.An optical card comprises a recording layer and a substrate, wherein said optical card has a conductive material layer capable of being electrostatically charged.A recording and/or reading apparatus employing an optical recording carrier or an optical card comprises a means for keeping electrostatically charged a plate constituting an optical recording carrier or optical card holder of which an optical recording carrier or optical card having a conductive material layer capable of being electrostatically charged is placed, to attract said optical recording carrier or optical card to said optical recording carrier or optical card holder by Coulomb's power, and a means for driving said optical recording carrier or optical card.

Abstract: An optical memory card subjected to optical information recording and reproduction, comprising, a card-like card body, an optical recording portion provided on said card body, and a light-transmitting portion formed in said card body for detecting an insertion state of said optical memory card in a card reader and/or writer.

Abstract: A chlorinated rubber having a chlorine content of 10 to 45% by weight based on the weight of the chlorinated rubber and a Mooney Viscosity, ML.sub.1+4 (121.degree. C.), of 10 to 190 is obtained by chlorinating an ethylene/alpha-olefin/non-conjugated diene copolymer rubber containing 5-vinyl-2-norbornene as the non-conjugated diene. The chlorinated rubber has excellent processability in roll milling, extrusion, etc.

Abstract: A chlorinated rubber having a chlorine content of 10 to 45% by weight based on the weight of the chlorinated rubber and a Mooney viscosity, ML.sub.1+4 (121.degree. C.), of 10 to 190 is obtained by chlorinating an ethylene/alpha-olefin/non-conjugated diene copolymer rubber containing 5-vinyl-2-norbornene as the non-conjugated diene. The chlorinated rubber has excellent processability in roll milling, extrusion, etc.