US Patent 9527645 Waterproof box structure

A waterproof box structure includes a composite plate and an external frame. The composite plate includes a chemical hardened layer and a thermoplastic resin layer attached to each other, and a surface of the thermoplastic resin layer is attached onto the chemical hardened layer, and the external periphery of the thermoplastic resin layer is extended and protruded from the external periphery of the chemical hardened layer. The external frame is formed and covered onto the external periphery of the composite plate by an injection molding method, and the internal periphery of the external frame is covered onto the external periphery of thermoplastic resin layer and combined with the thermoplastic resin layer.