Abstract: A method of supplying ink to ink ejection nozzles on a printhead for an inkjet printer with a print engine controller for controlling the printhead operation involving the provision a printhead IC having an array of the ink ejection nozzles formed on a substrate, the provision of circuitry for electrical connection to the print engine controller, the provision of a support member for supporting the printhead integrated circuit and the circuitry within the printer, the provision of a thermoplastic polymer sealing film, and securing the polymer film to a mounting surface of the support member by applying heat and pressure for a predetermined time, mounting the printhead integrated circuit and the circuitry to the support member via the polymer film and, electrically connecting the circuitry to the printhead integrated circuit. The mounting surface has ink feed channels formed in it and the polymer film is attached to the mounting surface between the ink feed channels and the printhead integrated circuits.