PURPOSE: To prevent the defect of a cathode and prevent a reduction in emission by forming a getter material arranged in a color cathode-ray tube by pulverizing, mixing and pressing its component in helium atmosphere.
CONSTITUTION: An electron gun body structure 8 having a cathode 8A installed thereto is arranged in the end part of the neck part 7 of the envelop 30 of a color cathode-ray tube, and a getter body 9 to be connected thereto through a leaf spring 15 is arranged in a funnel part 6. The getter body 9 is formed by housing a getter material mainly consisting of Ba in a cup vessel, and the tube inner part is held at a prescribed reduced pressure value. The getter material is formed by pulverizing, mixing and pressing its component in He atmosphere. The residual gas in the tube is thus mostly occupied by He having a low atomic weight, and even when it is ionized by an electron beam and collided, the impact to the cathode 8A is extremely minimized, and the cathode 8A is never damaged.
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