Abstract: A flexible EL device comprises a substrate, which is made of highly polymerized synthetic rubber, polyurethane, or silicon rubber, a conductive layer, a dielectric layer, a fluorescent layer, a transparent conductive layer, and a polymer protection film layer. Due to the high flexibility of the substrate, the flexibility of the flexible EL device according to the present invention is higher than the conventional EL device using PET, and therefore, the durability of the flexible EL device under mechanical impact is improved. As a result, the flexible EL device is not damaged when physical impacts are applied to the flexible EL device. Furthermore, noise is prevented or reduced by simply changing the structure of the flexible EL device and adding material layers, and therefore, electric and physical properties of the flexible EL device are improved. The flexible EL device is applicable to EL dome sheets or EL keypads.

Abstract: An EL sheet keypad comprises a conductive material layer coated on the entire surface of an EL sheet or the surface of the EL sheet where light is not emitted. The conductive material layer is connected to ground of a printed circuit board or to ground of the EL sheet by means of a conductive adhesive tape or conductive paste. According to the present invention, damage to the internal circuits of the mobile phone, which may occur when testing appropriateness of the EL sheet, is prevented. Furthermore, the EL sheet keypad has electrostatic shock and electromagnetic interference shielded functions.

Abstract: A flexible EL dome sheet uses a polymer insulation layer having a thickness of 5 to 50 ?m as a substrate, and therefore, the thickness of the flexible EL dome sheet is 50 to 150 ?m. The flexible EL dome sheet comprises a flexible EL sheet having key patterns formed thereon and metal or poly domes attached to the EL sheet. Since the flexible EL sheet and the metal or poly domes are used, the flexible EL dome sheet has excellent flexibility and durability, and an additional process for silicon molding is not necessary. Furthermore, the tactile feel of the flexible EL dome sheet keypad is improved. Electric connection between an EL driver of a flexible printed circuit board and the flexible EL sheet is achieved using a contact pad terminal structure, whereby no additional connector is necessary, and therefore, an FPC connecting process is not required.