Zirconia pre-sintered body for dental cutting and machining molded at different press pressure and manufacturing method thereof

A method of manufacturing a zirconia pre-sintered body for dental cutting and machining which has a multilayer structure in which two or more layers are stacked, comprising steps of:

• forming a green compact that constitutes a first layer by filling a mold with a zirconia powder for stacking and by powder compacting,
• forming a multilayer zirconia green compact by forming a second or more layers by filling a position adjacent the formed green compact in the mold with a zirconia powder for stacking and by powder compacting,
• performing isostatic press process on multilayer zirconia green compact, and pre-sintering the multilayer zirconia green compact performed with the isostatic press process, wherein
• in the step of forming a second or more layers,
• a zirconia powder for layering used in a green compact constituting each layer is different from a zirconia powder for layering used in a green compact constituting adjacent layer in relative density to the perfect sintered body in the green compact pressed at a press pressure of 4.78 kN/cm2, and
• each press pressure of the powder compacting in forming the green compact that constitutes each layer is adjusted so that the difference in relative density between the green compacts constituting respective layers is 2 or less, and
• in the step of pre-sintering,
• the multilayer zirconia green compact is pre-sintered at a temperature at which the processing coefficients of respective layers after pre-sintering are substantially equal.