Abstract: An EL lightening device which can individually switch the luminescence brightness of a plurality of ELs by a single inverter. In this device, a plurality of ELs (3) are connected to the output side of an inverter (1) through AC switches (2) A stabilized DC power supply (4) is connected to the input side of the inverter (1). A control circuit (5) is provided for controlling the lightening of the ELs (3) and is connected to the stabilized DC power supply (4) and the AC switches (2). The control circuit (5) outputs EL lightening signals to control ON/OFF operations of the transfers (2) and also applies an AC voltage to each EL (3) by time division so that said ELs are lightened. At the same time an inverter input voltage control signal is output in accordance with the timing at which the EL is lightened, so that the inverter input voltage of the stabilized DC power supply (4) can be varied.

Abstract: A process for producing a composite finger-touch key with superior fastness, in which the key top layer is chemically bonded to the key base piece even when a silicone resin is employed for the key base piece, which process is characterized by treating the surface of the key base piece to be bonded with the key top layer by exposing to a UV-irradiation or to a plasma discharge in order to subject the surface to a chemical activation, applying then a coupling agent based on silane, such as aminopropyl triethoxysilane, vinyl triethoxysilane and mercaptopropyl trimethoxysilane, to the so-treated surface of the key base piece, providing thereon with a layer of a resin curable by UV-irradiation or by heating, such as those based on, for example, acrylic, epoxy or silicone resin, of an adequate configuration and exposing the resin layer to a UV-irradiation or a heating to cause curing of the resin layer.

Abstract: A finger touch member of an illuminated switch prepared by a process comprising printing or coating a surface of a multicomponent rubber material composed of, as essential components, 90-70% by weight of EPDM and 5-30% by weight of liquid polymerized butadiene rubber, with an ink of contemplated color, covering the entire top face of the resulting printed or coated cover piece with a light blocking coating layer and irradiating the so covered top face with a laser beam to cut out the coating layer in a contemplated pattern.