THREE-WAY STOPCOCK UNIT, CHECK VALVE, AND FLUID SUBSTANCE TRANSFER DEVICE

摘要

Provided are a three-way valve unit, a non-return valve, and a fluid material transfer device that are readily made more compact and have high yields and low production costs. The non-return valve in the three-way valve unit comprises: a first housing with a valve seat and with an opening disposed therein; a second housing that is inserted into the first housing; and a valve sandwiched between the valve seat in the first housing and an opening end section in the second housing. The valve has a substantially U-shaped slit provided further outside than an outer peripheral edge section of the opening provided in the valve seat in the first housing and further inside than an inner peripheral edge section in the second housing. The inside part of the slit is used as an open-close valve and the first housing valve seat and the second housing opening end section are blocked in a liquid-tight state by an outside section of the slit.