| 摘要 |
PROBLEM TO BE SOLVED: To produce a fibrous aluminum compd. AACH and its fired body optimum for producingα-alumina single-crystalline particles having a fibrous form and alumina type oxide fibers. SOLUTION: An aq. soln. or suspension of a water-soluble or slightly water- soluble aluminum compd. such as aluminum sulfate, aluminum chloride, aluminum ammonium sulfate, aluminum hydroxide, aluminum ethoxide, aluminum isopropoxide or acetylacetonatoaluminum and, etc., is injected into an aq. NH4 HCO3 soln. having such a sufficiently high concn. of CO3 <2-> ions as >=0.01 mol/l or a basic aq. soln. having a sufficiently high concn. of CO3 <2-> ions and contg. NH4 <+> ions and aging is carried out by heating at >=100 deg.C to produce the objective fibrous single-crystalline particles of AlNH4 CO3 (OH)2 having an aspect ratio of >=10, >=0.5μm length and >=0.01μm thickness. The objective fired body of the fibrous particles is produced by heating the fibrous particles to >=1,000 deg.C.
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