(19)
(11) EP 1 180 763 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
12.03.2003 Bulletin 2003/11

(43) Date of publication A2:
20.02.2002 Bulletin 2002/08

(21) Application number: 01110763.8

(22) Date of filing: 03.05.2001
(51) International Patent Classification (IPC)7: G10K 11/162
(84) Designated Contracting States:
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR
Designated Extension States:
AL LT LV MK RO SI

(30) Priority: 15.08.2000 JP 2000246111
23.08.2000 JP 2000251880

(71) Applicant: Mitsubishi Heavy Industries, Ltd.
Tokyo (JP)

(72) Inventors:
  • Hasezaki, Kazuhiro, Nagasaki R & D Center
    Nagasaki, Nagasaki-ken (JP)
  • Motomura, Hikaru, Nagasaki R & D Center
    Nagasaki, Nagasaki-ken (JP)
  • Seki, Shiro, Nagasaki Shipyard & Machinery Works
    Nagasaki, Nagasaki-ken (JP)
  • Shibata Seizou, Nagasaki Shipyard Machinery Works
    Nagasaki, Nagasaki-ken (JP)

(74) Representative: Henkel, Feiler, Hänzel 
Möhlstrasse 37
81675 München
81675 München (DE)

   


(54) Ceramic sound absorbing material and manufacturing method therefor


(57) An object of the present invention is to reuse wastes of used or defective sound absorbing material body as a raw material for sound absorbing material body. As aggregates for the sound absorbing material of the present invention, ground mullite particles with an average particle size of about 0.5 to 1 mm are used. As a binder, polyethylene terephthalate (hereinafter referred to as PET) resin, which is a thermoplastic resin, of a form of pellet not larger than 1 mm is used. The aggregates are heated to a temperature in the range of 245°C to 290°C, which is the melting point of PET resin. In order to ensure the smoothness of surface layer when a mixture is poured into a mold, pressing with a pressure of 40 to 1000 kgf/cm2 is performed. After pressing, the product is cooled and solidified, and then is removed from the mold, whereby a sound absorbing board with a thickness of 8 mm is obtained.






Search report