Abstract: A polycarbonate resin reduced in the release of environmental hormones which comprises structural units represented by general formula (A) and structural units represented by general formula (B), the structural units represented by general formula (A) accounting for 5 to 90 mol % of all the structural units, and which has an intrinsic viscosity of 0.30 to 0.60 dl/g. The polycarbonate resin is produced through the copolymerization of a bispenol whose ability to link to estrogen acceptors is low with an aliphatic dihydroxy compound. The resin hence has the basic properties inherent in polycarbonates, i.e. mechanical strength and heat resistance, and is reduced in the release of environmental hormones.

Abstract: A control method of a DC motor is described which comprises a digital control method and an analogue control method, wherein a rotor of the DC motor rotates with high speed under the digital control method until the rotating angle of the rotor comes close to a predetermined rotating angle and then the rotor rotates with high accuracy under the analogue control method to the predetermined rotating angle.