Degassing unit for high performance liquid chromatography

In a degassing unit to be used for high performance liquid chromatography systems, which draws an eluent from a reservoir by a fluid delivery pump and which, removes gases dissolved in the eluent and delivers the gas removed eluent via a sample injection valve to a detection means including a separation column, the degassing unit being installed between the reservoir and the fluid delivery pump, and the degassing unit being characterized by having a degassing module comprising:

• a flat hollow enclosure consisting of two degassable film sheets having fringes which are sealed hermetically to form an internal space, and having two independent openings at separate positions;
• one for an inlet to feed eluent in and the other for an outlet to feed said eluent out;
• two sheet plates having a plurality of holes, of the same shape as that of said film sheets, each of which is closely fitted to either side of the film sheets to prevent the expansion of the internal spaces of said hollow enclosure;
• a pair of holding frames about said fringes of said hollow enclosure and the fringes of the sheet plates and which permits exposure of said surface areas of said sheet plates;
• and a vacuum chamber for accommodating said degassing module and also providing a surrounding space around said degassing module, and, a vacuum pump which reduces pressure inside the said vacuum chamber.