Ivoclar Vivadent IPS Empress Esthetic - Manual (Page 29)

29
Remove the investment ring from the furnace immediately after the program is completed and close the furnace. Place the
investment ring on the cooling grid and allow it to cool to room temperature. The grid ensures quick and even cooling of
the investment ring and prevents undesired heat accumulation.
Divesting
After cooling to room temperature (after approximately 60 minutes), the investment ring may show cracks. These cracks
developed (immediately around the AlOx plunger) during cooling as a result of the different CTEs of the various materials
(AlOx plunger, investment material, and pressed materials). They do not compromise the press result.
– Mark the length of the AlOx plunger on the cooled investment ring.
– Separate the investment ring using a separating disk. This predetermined breaking point enables reliable separation of
the AlOx plunger and the ceramic material.
– Break the investment ring at the predetermined breaking point using a plaster knife.
– Rough divestment is carried out with glass polishing beads at 4 bar (60 psi) pressure.
– For fine divestment, only 2 bar (30 psi) pressure is applied.
– Do not use Al 2 O 3 for rough or fine divestment
– When divesting the object, blast from the direction indicated in the schematic below
and observe the appropriate distance in order not to damage the object margins.
– The investment material contains quartz powder. Therefore avoid any inhalation of
dust.
– Use Al 2 O 3 to clean the AlOx plunger from any ceramic residue.
Position the investment ring in the press furnace Place the investment ring on the cooling grid
Mark the length of the AlOx plunger
Separate the investment ring using a separating disk and break it at the predetermined breaking point.