Patent attributes
The present invention addresses a problem of providing a composite seal material that has performances, such as a vacuum sealing performance, plasma resistance, and corrosive gas resistance, in combination, that does not require a strong pressing force during use, that does not have a possibility of generating particles, and that is capable of maintaining the vacuum sealing performance for a long period of time. Characteristics of a solution to the problem is a composite seal material having an annular shape and including a first member and a second member adjacent to each other on left and right. The first member includes a seal body portion, and a lip portion extending from the seal body portion upwardly in the thickness direction of the composite seal material. The lip portion of the first member extends in an inclined orientation outwardly on a side opposite to the second member adjacent thereto.