Patent ID: 8042924

Claim:
A method for manufacturing an attachment structure including a liquid supply needle and a holder base, the method comprising: welding the holder base to the liquid supply needle by ultrasonic welding, wherein the holder base includes a base bonding part comprising a first ring which protrudes from a peripheral edge of a filter receiving part which is configured to house a filter and wherein the liquid supply needle includes a needle bondage part formed adjacent to and outside of an opening of the liquid supply needle, the needle bondage part comprising a second ring protruding from a surface of a liquid supply surface facing the holder base, the needle bondage part having flat surface facing the base bonding part with a protruded part formed thereon; and raising the melting point of the protruded part by performing an anneal process, an infrared ray projecting process, or an injection molding process at a molding temperature of 150 degrees Celsius or above, and wherein a horizontal width of the needle bondage part is smaller than a horizontal width of the base bondage part and wherein the horizontal width of the protruded part is smaller than the horizontal width of the needle bondage part.