PURPOSE: To shorten the time for degreasing by specifying the flow rate of a heating gas to be passed during degreasing at the time of subjecting the molding obtd. by injection molding of the kneaded matter composed of ceramics powder and org. binder powder to degreasing and calcining.

CONSTITUTION: The kneaded matter is prepd. by mixing the ceramics powder and the org. binder powder and heating the mixture to soften and melt the org. binder. The injection molding is obtd. by injection molding of this kneaded matter. While the gas is kept flowing, the above-mentioned molding is heated to remove the org. binder in the molding. The heated nonoxidizing gas of 1atm is passed in this degreasing stage and the flow rate of the gas near the surface of the molding is controlled to 0.5W20cm/min at this time. The speed of removing the org. binder is thereby increased without cracking and deforming the molding.