Title:
SOUND ABSORBING MATERIAL
Document Type and Number:
Japanese Patent JP2021177238
Kind Code:
A
Abstract:
To provide a sound absorbing material capable of achieving a high sound absorbing coefficient α over a wide frequency band, in particular, to provide a sound absorbing material which exhibits excellent sound absorbing performance by an aggregate of resin fibers such as polypropylene fiber, with high quality and high production efficiency.SOLUTION: In a sound absorbing material made of an aggregate of resin fibers, an average fiber diameter of the resin fibers is 3000 nm or more and less than 8000 nm, and a porosity of the aggregate is 0.95 or more and 0.99 or less. Alternatively, the average fiber diameter of the resin fibers may be 4450 nm or more and less than 7700 nm, and the porosity of the aggregate may be 0.92 or more and 0.99 or less. It is desirable that flow resistance of the aggregate is 100,000 [Ns/m4] or less. It is desirable that the resin fibers constituting the aggregate are made of a thermoplastic resin. Preferably, the thermoplastic resin has a melting point of less than 200°C. As such a thermoplastic resin, polyolefin, particularly polypropylene, can be used.SELECTED DRAWING: Figure 17
Inventors:
SODA HIROYOSHI
WU WEI
WU WEI
Application Number:
JP2021076577A
Publication Date:
November 11, 2021
Filing Date:
April 28, 2021
Export Citation:
Assignee:
M TECHX INC
WU WEI
WU WEI
International Classes:
G10K11/162
Attorney, Agent or Firm:
Patent business corporation Prospec patent office
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