ANNULAR DIE FOR PRODUCING RESIN FOAM, APPARATUS FOR PRODUCING RESIN FOAM, AND METHOD FOR PRODUCING RESIN FOAM

摘要

PROBLEM TO BE SOLVED: To provide an annular die for producing a resin foam capable of avoiding streaks generated on the resin foam, an apparatus for producing the resin foam, and a method for producing the resin foam.SOLUTION: The annular die for producing a resin foam is provided with an outer die and an inner die fixed within the outer die. The annular die has: an opening opened at one end; a resin flow passage extended from the opening in a predetermined direction; a foaming part narrowed relative to the resin flow passage; and a foam-forming part widened relative to the foaming part, and extended toward the outside from the extended direction of the resin flow passage. The foaming part is constituted by an r-part of the outer die, and an r-part of the inner die disposed along the r-part of the outer die.The ratio (RI/RO) of a corner radius RI of the r-part of the inner die to a corner radius RO of the r-part of the outer die is not less than 7.