Patent ID: 7879169

Claim:
A method for producing a ceramic compact, comprising: a laminate-preparing step of preparing an unfired laminate including a base layer and a constraining layer, the base layer including a ceramic powder and a glass material, and the constraining layer being arranged in contact with at least one principal surface of the base layer and primarily including a burnable material which does not burn off when the burnable material is fired in a low-oxygen atmosphere but which burns off when the burnable material is fired at an oxygen partial pressure greater than that of the low-oxygen atmosphere; and a firing step of firing the unfired laminate to sinter the base layer; wherein the firing step includes a first firing sub-step of firing the laminate including the constraining layer to sinter the base layer and a second firing sub-step of firing at an oxygen partial pressure greater than that of the first firing sub-step such that the constraining layer burns off; the burnable material is a carbon powder; and the carbon powder has a particle size of about 1 μm to about 5 μm.