Patent ID: 7862874

Claim:
A welded resin material comprising a resin member having transmissibility to laser light, a resin member having absorptivity to laser light, a joined part comprising a contact part of the resin members superimposed to each other that has been welded with laser light, and a closed space that is adjacent to the contact part and faces one end of the contact part, the closed space having housed therein a resin excluded from the contact part melted and solidified; wherein the contact part of the resin members is formed by making an annular projection of one of the resin members in contact with the other of the resin members, and the other of the resin members has an annular projection that extends from the other resin member toward the one resin member, overlaps a peripheral surface of the annular projection of the one resin member, is interdigitated with the annular projection of the one of the resin members on a side of the contact part opposite to the closed space, and prevents the melted resin from being excluded to a side of the contact part opposite to the closed space.