To ensure a high sound absorbing property as well as its strength by laminating an inorganic honeycomb structural body on one surface of open cell foam bodies formed of a curable inorganic composition.
Inorganic honeycomb structural bodies 11, 12 are formed such that a sheet-like matter formed by subjecting an inorganic fiber substance having a sheet forming ability to a paper making process is worked into honeycomb structural bodies 11, 12. In this case, reinforcing material is added as required in a slurry consisting mainly of an inorganic fiber substance having a sheet forming ability. Also, a film of a hydraulic inorganic substance is formed on the surface of the honeycomb structural bodies 11, 12 for purposes of giving a mechanical strength or water resistance reinforcement thereto. Furthermore, a plurality of inorganic honeycomb structural bodies 11, 12 are laminated in multi-layer relation in its opening surface in a manner allowing the structural bodies 11, 12 to cross over in its cross-sectional surface. By setting the diameter of honeycomb cells in 6-60mm, the height in 1-15mm, the number of lamination layer in 2-10 steps, and the total height of lamination in 2-40mm, an sound absorbing property and strength can be ensured.
YOKOYAMA YUZO
KUSANO KUNIO
MINAMI KATSUTOSHI
