Patent ID: 8371835

Claim:
A mold for extrusion forming of ceramic articles comprising: a die having a plurality of back holes which are provided in a supply end and through which a kneaded clay is supplied, and slits which are provided in an extrusion end so as to communicate with the plurality of back holes and through which the kneaded clay is extruded to form the ceramic articles; a back pressing plate and a back spacer which are arranged on an outer peripheral side of the supply end of the die to adjust an amount of the kneaded clay to be supplied; and a pressing plate and a spacer which are provided on an outer peripheral side of the extrusion end of the die to regulate a shape and a size of the formed ceramic articles, wherein at least a portion of the supply end of the die which overlaps with the back pressing plate is flattened so that over any distance between adjacent back holes, a height difference between protrusions and recesses, which were formed by electrical chemical machining (ECM), does not exceed 65 μm, a surface roughness (Ra) of the portion of the supply end is in a range of 0.05 μm to 10 μm, and a distance between the centers of the adjacent back holes is 0.5 mm to 1.8 mm.