Sealing Device

A sealing device having:

• a slide ring made of a resin;
• and a back ring made of an elastic body joined to an inner peripheral surface or outer peripheral surface of the slide ring as a junction surface;
• the sealing device being configured to seal an annular gap between a housing having a shaft hole, and a shaft inserted through the shaft hole in a manner to conduct a movement relative to the housing;
• wherein the slide ring has:
• a through-cut in a step cut shape, comprising a single circumferential cut extending along a circumferential direction of the slide ring, and two axial cuts extending from both ends of the circumferential cut in mutually opposite directions, respectively, along the axial direction of the slide ring;
• and multiple parting lines formed on a surface of the slide ring along the circumferential direction of the slide ring, where the parting lines have been formed by injection molding the slide ring by a mold dividable into multiple partial molds at multiple junction of molds along the circumferential direction of the mold, and by subsequently parting the mold at the junction of molds;
• and
• wherein the parting lines are arranged so that the parting lines are not overlapped with the circumferential cut exposed at the junction surface of the slide ring with the back ring, throughout the lengthwise direction of the circumferential cut.