Press die for molding sipe blade and method for making the press die

Provided is a press die for molding a sipe blade which can efficiently mold a sipe blade having a complicated shape such as three-dimensional shape and having excellent mechanical strength characteristics and which can reduce production cost due to its simple structure, and further provided is a method for simply and efficiently making a press die for molding a sipe blade having a complicated shape such as a three-dimensional shape by a casting method. The press die 10 for molding the sipe blade of the present invention is composed of a pair of the divided parts composing a press die 1 and 2, and a material 3 for the sipe blade is interposed and pressed between the pair of the divided parts composing a press die to mold a sipe blade 4 having a desired shape, and is characterized in that portions 1a and 2a to which is applied a load caused by a molding pressure in contact with the material 3 for the sipe blade for giving a desired shape to the sipe blade 4 have the shapes corresponding to a desired shape of the sipe blade 4, and portions 1b and 2b to which is not applied a load caused by molding pressure without contacting with the material 3 for the sipe blade are provided with first relief parts 5 which do not correspond to the desired shape of the sipe blade 4 and do not substantially contact with the sipe blade after molded.