| 摘要 |
PROBLEM TO BE SOLVED: To provide an alumina short fiber aggregate having a high tensile strength and 3 to 8μm mean fiber diameter, and a method for producing the same. SOLUTION: This alumina short fiber aggregate is provided by having≥99 mass% (including 100%) Al<SB>2</SB>O<SB>3</SB>content, 3 to 8μm mean fiber diameter and 300 to 500 MPa mean tensile strength. The method for producing the alumina short fiber aggregate is characterized by passing through the following (1) to (3) processes: (1) a process of preparing an aqueous solution containing 25 to 30 mass% basic aluminum chloride in Al<SB>2</SB>O<SB>3</SB>, 1.5 to 3.5 mass% polyvinyl alcohol and 0.5 to 1.5 mass% polyethylene oxide and having 1,500 to 6,000 mPa s viscosity at 20°C, (2) a process of using the aqueous solution as spinning stock liquid, ejecting from a plurality of fine holes installed at the sidewall of a rotary hollow disc and forming liquid fibers to make precursor fibers, and (3) a process of collecting the precursor fibers, burning and then cooling. COPYRIGHT: (C)2011,JPO&INPIT |
