Porous stamp assembly, and manufacturing method and apparatus of the same

A manufacturing method of a porous stamp assembly, comprising the steps of

• hermetically adhering a thin porous impression die member of thermoplastic resin to a front end face of a frame, for preparing a die member adhered frame, wherein the thin porous impression die member has a rear, ink impregnating face and a front, impression surface,
• fixing the die member adhered frame onto a mount having a recipient major surface that is to be in face-to-face relation with a thermal head attached to a seal carving device, with the recipient major surface of the mount in contact with the rear, ink impregnating face of the thin porous impression die member, wherein the recipient major surface of the mount is planar and of sufficient hardness to protect the mount from deformation when the thin porous impression die member comes into contact with the thermal head,
• carving the impression surface of the thin porous impression die member into an impression die without deforming the mount at the recipient major surface thereof, by putting the thermal head in contact with the impression surface of the thin porous impression die member, with a resin film interposed therebetween, and moving the thermal head and the thin porous impression die member relative to each other in a direction parallel to the plane of the recipient major surface of the mount,
• removing the die member adhered frame from the mount after the carving step, and
• after step of removing the die member adhered frame from the mount, fitting the die member adhered frame in a holder holding an ink retainer soaked with ink, with the rear, ink impregnating face of the thin porous impression die member in contact with the ink retainer soaked with ink, to impregnate the carved thin porous impression die member with ink.