Patent ID: 8162152

Claim:
A blood filter device comprising: a housing that includes a dome provided with a blood inlet and forming an upper part of the housing, a filter retaining portion positioned below the dome and forming a middle part of the housing, and a bottom portion disposed below the filter retaining portion and provided with a blood outlet; and a filter mounted in a cavity of the filter retaining portion and partitioning a cavity of the housing into a dome side and a bottom portion side, the filter formed of a sheet-like filter member folded to have a plurality of pleats, and disposed so that ridgelines of the plurality of pleats traverse respectively the cavity of the filter retaining portion in parallel, wherein the blood filter device comprises: an annular holder disposed to intervene between an inner peripheral surface of the filter retaining portion and an outer peripheral surface of the filter; an annular rib substrate, which is an annular member including a plurality of ribs that is formed separately from the annular holder, and is disposed on the ridgelines of the plurality of pleats in an outer peripheral region of the filter so that the ribs are inserted respectively between the ridgelines of the plurality of pleats; an auxiliary bonding resin that bonds an outer periphery of the filter to an inner peripheral surface of the annular holder, positioning the annular rib substrate at an area inside the auxiliary bonding resin, with an interval provided in a radial direction between an outer peripheral edge of the annular rib substrate and an inner peripheral edge of the auxiliary bonding resin; and a bonding resin that is supplied into outer peripheral portions of the filter including the annular holder and the annular rib substrate and bonds the outer peripheral portion of the filter to the filter retaining portion.