PURPOSE: To accomplish a bonding of high strength in a short time, by mounting a detachable defoaming vessel on one flat plate to pour therein an adhesive to spread it to small thickness followed by vacuum defoaming then detaching the vessel to press the other flat plate on the above plate.

CONSTITUTION: Through the inlet 17 of vacuum defoaming vessel 13 mounted on flat plate 15, is poured an adhesive on said plate 15 to spread it to small thickness. Following that, defoaming is carried out using vacuum pump 16, then the other plate being mounted on the plate 15 to perform contact bonding to accomplish the objective bonding.