Separating method for dark ceramics sintered body

A separating method for separating a dark ceramics sintered body and a conductive ceramics sintered body, using an aqueous solution for separation having a hydrofluoric acid concentration of 0.05 to 0.75 mol/l, from a glass formed with both of the dark ceramics sintered body and the conductive ceramics sintered body on a surface thereof, the method comprising:

• separating the conductive ceramics sintered body from the glass formed with both of the dark ceramics sintered body and the conductive ceramics sintered body on the surface thereof by immersing the glass in the aqueous solution for separation during a first separation time period;
• separating the dark ceramics sintered body from the glass formed with both of the dark ceramics sintered body and the conductive ceramics sintered body on the surface thereof by immersing the glass in the aqueous solution for separation during a second separation time period longer than the first separation time period, wherein a difference in length between the first separation time period and the second separation time period is not less than one minute;
• wherein the glass, the dark ceramics sintered body, and the conductive ceramics sintered body are separately collected utilizing the difference in length between the first separation time period and the second separation time period.