PURPOSE: To obtain a thermoplastic molding composition from which the binder can be removed within a short time when sintered by heating by mixing a ceramics with a specified antioxidant containing a hindered phenol or the like.

CONSTITUTION: This composition is prepared by mixing (A) a sinterable ceramics or metal with (B) thermoplastic binder containing (C) an antioxidant at the softening point of component B or higher. Component B is a mixture of a thermoplastic polymer with an organic wax, etc., and desirably has a softening point of 50-150°C. It is desirable that component C is effective at 200°C or above, and needs to have a boiling point of 250°C or above. Component C is desirably a hindered phenol or aromatic amine or one containing a divalent sulfur or trivalent phosphorus compound, and is used in an amount of about 0.01 to 5 wt.% based on component B. More desirably, 1-70 wt.%, based on component B, silicone resin is used. When sintered, this composition can give a non- defective highly dense object.