公开(公告)号：US11186931B2

公开(公告)日：2021-11-30

申请号：US16603937

申请日：2018-04-10

Applicant: UNITIKA LTD.

Inventor： Kazutoshi Hanaya ,  Toru Takahashi ,  Hideaki Kaminokado ,  Masaya Akao ,  Yusuke Nagatsuka

IPC: D04H1/485 ,  D04H1/4382 ,  D04H1/541 ,  A47L13/16 ,  D04H1/435 ,  D04H1/559

Abstract: [Problem] To provide a process for producing a needle-punched nonwoven fabric with which, when finished by embossing, it is possible to obtain a hardly fluffing and distinct rugged pattern.
[Solution] Sheath-core composite fibers are accumulated and a fibrous web is formed. The core component of the sheath-core composite fiber is formed from a copolymer of ethylene glycol and terephthalic acid. The sheath component is formed from a copolymer of ethylene glycol, adipic acid, terephthalic acid, isophthalic acid and diethylene glycol. The sheath-core composite fibers are three dimensionally interlaced with each other by needle-punching the web, to obtain the needle-punched nonwoven fabric. The needle-punched nonwoven fabric is passed through heated embossed roll to provide a rugged pattern on a surface. During the process, the sheath component are softening melted and melt bonded between the sheath-core composite fibers to obtain an embossed nonwoven fabric having a distinct rugged pattern.

公开(公告)号：US11525220B2

公开(公告)日：2022-12-13

申请号：US16605385

申请日：2018-04-18

Applicant: UNITIKA LTD.

Inventor： Kazutoshi Hanaya ,  Masaya Akao ,  Yusuke Nagatsuka

IPC: D21J1/04 ,  D21H13/24 ,  D21H15/10 ,  D04H1/48 ,  D01F8/14 ,  D04H1/541

Abstract: An object of the present invention is to provide a process for producing fiberous board with which fiberous board exhibiting high bending strength and high stiffness at a wide range of heating temperatures and a wide range of compressing and heating times. In the present invention, fiberous board having an initial flexural modulus of at least 300 MPa in three point bending test is obtained by forming a web by correcting sheath-core composite fibers of which a core component is formed from a copolymer of ethylene glycol and terephthalic acid and the sheath component is formed from ethylene glycol, adipic acid, terephthalic acid, isophthalic acid; and/or diethylene glycol. The web is then compressed in a direction of thickness and heated, so that the sheath component softens and melts and the sheath-core composite fibers are melt bonded together and molded into a flat plate shape.