A cartridge detachably mountable to a main assembly of an image forming apparatus, comprising: a cartridge frame formed of a first resin material; and a plurality of resin members (14, 15, 16, 17) molded on said cartridge frame by injection molding of a second resin material different from the first resin material, wherein the cartridge frame includes a plurality of contact surfaces (13a, 13b, 13c, 13d) with which metal molds (50, 51, 52, 53) corresponding to the resin members (14, 15, 16, 17) contact so as to form molding spaces between said metal molds (50, 51, 52, 53) and said cartridge frame when the resin members (14, 15, 16, 17) are molded, characterized in that said cartridge frame further includes (i) a plurality of resin material inlet ports (25, 26, 27, 28, 28a, 28b) arranged at a side of said cartridge frame opposite to a second side of said cartridge frame where the contact surfaces (13a, 13b, 13c, 13d) are provided, (ii) a plurality of resin material outlet ports arranged at the second side of said cartridge, and (iii) passages penetrating said cartridge frame from the plurality of resin material inlet ports (25, 26, 27, 28, 28a, 28b) to associated ones of the plurality of resin material outlet ports, wherein the resin members (14, 15, 16, 17) are molded on the cartridge frame by the second resin material being injected into the molding spaces from the plurality of resin material inlet ports (25, 26, 27, 28, 28a, 28b) so to flow through the passages and the plurality of resin material outlet ports, and wherein the plurality of resin material inlet ports (25, 26, 27, 28, 28a, 28b) are arranged so as to overlap with the associated ones of the plurality of resin material outlet ports when viewed in a direction in which the second resin material is injected into the plurality of resin material inlet ports (25, 26, 27, 28, 28a, 28b). a cartridge frame formed of a first resin material; and a plurality of resin members (14, 15, 16, 17) molded on said cartridge frame by injection molding of a second resin material different from the first resin material, wherein the cartridge frame includes a plurality of contact surfaces (13a, 13b, 13c, 13d) with which metal molds (50, 51, 52, 53) corresponding to the resin members (14, 15, 16, 17) contact so as to form molding spaces between said metal molds (50, 51, 52, 53) and said cartridge frame when the resin members (14, 15, 16, 17) are molded, characterized in that said cartridge frame further includes (i) a plurality of resin material inlet ports (25, 26, 27, 28, 28a, 28b) arranged at a side of said cartridge frame opposite to a second side of said cartridge frame where the contact surfaces (13a, 13b, 13c, 13d) are provided, (ii) a plurality of resin material outlet ports arranged at the second side of said cartridge, and (iii) passages penetrating said cartridge frame from the plurality of resin material inlet ports (25, 26, 27, 28, 28a, 28b) to associated ones of the plurality of resin material outlet ports, wherein the resin members (14, 15, 16, 17) are molded on the cartridge frame by the second resin material being injected into the molding spaces from the plurality of resin material inlet ports (25, 26, 27, 28, 28a, 28b) so to flow through the passages and the plurality of resin material outlet ports, and wherein the plurality of resin material inlet ports (25, 26, 27, 28, 28a, 28b) are arranged so as to overlap with the associated ones of the plurality of resin material outlet ports when viewed in a direction in which the second resin material is injected into the plurality of resin material inlet ports (25, 26, 27, 28, 28a, 28b).