US Patent 7281566 Method for manufacturing mold

A method for manufacturing a mold (70), which comprises a step of forming a layer (31) of combustible powdery particles (32) around a wax mold (21), which is a lost pattern, a step of forming a film (51) of a ceramic precursor slurry (52) around the wax mold (21) having powdery particles (32) formed thereon, a step of subjecting the resultant product to a heat treatment, to thereby dewax the wax mold (21), and a step of firing the slurry film (51), to thereby burn and vanish the powdery particles (32) in the slurry film (51) and form a shell (71). The mold (70) has the shell (71) and a porous layer (74) formed on the surface (76) of the cavity of the shell. The mold can be suitably used for manufacturing a porous body (90) having a porous layer (94) on the surface thereof.