Title:
LIGHT TRANSMISSION CERAMIC, ITS PRODUCTION, AND ARC TUBE AND HIGH-VOLTAGE DISCHARGE LAMP BY USING LIGHT TRANSMISSION CERAMIC
Document Type and Number:
Japanese Patent JPH11157933
Kind Code:
A
Abstract:
To obtain a light transmission ceramic comprising Er2O3, Tm2O3, Ho2O3, Yb2O3 or Lu2O3 and having high transparency and excellent strength.
An aqueous solution containing sulfuric acid ion and an aqueous solution of urea are added to an aqueous solution of mineral acid salts of Er, Tm, Ho, Dy, Yb and Lu and carbonates of the rare earth metals are precipitated in an autoclave. The precipitate is filtered, washed and dried, and the dried precipitate is calcined at about 1,200°C. CaO of 5-1,000 wt.ppm is added to the calcined precipitate and compacted. The compact is sintered in vacuum at about 1,700°C to provide an arc tube 2 in a high-voltage discharge lamp 1.
Inventors:
YANAGIYA TAKAKIMI
ICHIKAWA AKIFUMI
YAMAZAKI HIROO
NISHIGUCHI TAKAKO
UTSUNOMIYA NORIAKI
ICHIKAWA AKIFUMI
YAMAZAKI HIROO
NISHIGUCHI TAKAKO
UTSUNOMIYA NORIAKI
Application Number:
JP33802597A
Publication Date:
June 15, 1999
Filing Date:
November 21, 1997
Export Citation:
Assignee:
KONOSHIMA CHEMICAL
International Classes:
C04B35/50; H01J61/20; H01J61/30; H01J61/36; (IPC1-7): C04B35/50; H01J61/20; H01J61/30; H01J61/36
Attorney, Agent or Firm:
Akira Shioiri (1 person outside)
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