PURPOSE: To realize extraordinarily weight reduction of the title box body by making the box body ultrathin without deteriorating rigidity, fitting properties, shock resistance and weld stability, by forming singly of thermoplastic resin or composite material obtained by filling at least one kind of reinforcement material selected out of specific material into the thermoplastic resin and molded extraordinarily thin.
CONSTITUTION: For example, a portable telephone enclosure 1 with a plane antenna aiming at miniaturization and weight reduction is formed of cases each such as a U case 1A in which a speaker part 3, display part 4 and operation button part 5 are arranged, an L case 1B for installation of a plane antenna and a slide case 1C for holding the secondary battery, the cases each are integrated by fitting in each other after they are molded separately by an injection molding method. Then the respective cases are formed of either thermoplastic resin singly or a composite material obtained by filling at least one kind of reinfocement material to be selected out of a carbon fiber, glass fiber, organic filler and inorganic filler into the thermoplastic resin and formed extraordinarily thin having a thickness of not exceeding 0.1mm.
NISHI SHIRO
NAKAMURA KOZABURO
URABE SHUJI
