Apparatus for manufacturing non-woven fabric, method of manufacturing non-woven fabric, and non-woven fabric

Abstract

A diffusing unit of an apparatus for manufacturing a non-woven fabric is provided with a diffusion space between a jet nozzle and a moving belt of a collecting unit, an opening of a sub nozzle is arranged side-by-side with an opening of the jet nozzle, and the sub nozzle jets air from the opening. The jet nozzle jets, toward the moving belt, plural filaments together with air. The air jetted from the jet nozzle forms a conveying flow that gradually spreads and flows in the diffusion space, and the plural filaments are diffused by this conveying flow and are sent toward the moving belt to be collected. The air jetted from the sub nozzle flows along the air flow around the conveying flow and suppresses air in the diffusion space from entering the conveying flow.

1 . An apparatus for manufacturing a non-woven fabric, the apparatus comprising:
 a collecting unit that collects, on a collecting medium, filaments that are jetted toward the collecting medium;   a diffusing unit comprising a main nozzle that jets, toward the collecting medium, air that is supplied together with the filaments that are to be collected on the collecting medium, and a diffusion space that is provided between the main nozzle and the collecting medium and in which the filaments are diffused by an air flow in which the air jetted, together with the filaments, from the main nozzle is flowing while being diffused; and   an air flow generator that generates, around the air flow of the air jetted from the main nozzle into the diffusion space, an air flow that is close to and follows the air flow.   
     
     
         2 . The apparatus for manufacturing a non-woven fabric according to  claim 1 , wherein the air flow generator comprises a sub nozzle that jets air into the diffusion space. 
     
     
         3 . The apparatus for manufacturing a non-woven fabric according to  claim 1 , wherein the air flow generator comprises a sub nozzle that has an opening portion arranged side-by-side with an opening portion of the main nozzle, and that jets air into the diffusion space. 
     
     
         4 . The apparatus for manufacturing a non-woven fabric according to  claim 2 , wherein the sub nozzle is provided at a machine direction side of the main nozzle and at an opposite side of the main nozzle from the machine direction side. 
     
     
         5 . The apparatus for manufacturing a non-woven fabric according to  claim 2 , wherein a flow velocity of the air jetted from the sub nozzle is equal to or lower than a flow velocity of the air jetted from the main nozzle. 
     
     
         6 . The apparatus for manufacturing a non-woven fabric according to  claim 5 , wherein the flow velocity of the air jetted from the sub nozzle is no lower than 1/10 of the flow velocity of the air jetted from the main nozzle. 
     
     
         7 . A method of manufacturing a non-woven fabric, the method comprising:
 providing, between a main nozzle, from which air is jetted together with filaments, and a collecting medium, that collects the filaments jetted from the main nozzle, a diffusion space in which the filaments are diffused by an air flow in which the air jetted, together with the filaments, from the main nozzle is flowing while being diffused;   jetting, toward the collecting medium, the filaments together with the air from the main nozzle, while generating, by an air flow generator, and around the air flow of the air jetted from the main nozzle into the diffusion space, an air flow that is close to and follows the air flow; and   collecting and depositing, on the collecting medium, the filaments that have been diffused in the diffusion space.   
     
     
         8 . The method of manufacturing a non-woven fabric according to  claim 7 , further comprising jetting, into the diffusion space, air from a sub nozzle that has an opening portion arranged side-by-side with an opening portion of the main nozzle, to generate, around the air flow of the air jetted from the main nozzle into the diffusion space, an air flow that is close to and follows the air flow. 
     
     
         9 . The method of manufacturing a non-woven fabric according to  claim 8 , wherein the sub nozzle is provided at a machine direction side of the main nozzle and at an opposite side of the main nozzle from the machine direction side. 
     
     
         10 . The method of manufacturing a non-woven fabric according to  claim 8 , wherein a flow velocity of the air jetted from the sub nozzle is equal to or lower than a flow velocity of the air jetted from the main nozzle. 
     
     
         11 . The method of manufacturing a non-woven fabric according to  claim 10 , wherein the flow velocity of the air jetted from the sub nozzle is no lower than 1/10 of the flow velocity of the air jetted from the main nozzle. 
     
     
         12 . A non-woven fabric, wherein a ratio of a strength at 5% elongation in a machine direction to a strength at 5% elongation in a direction perpendicular to the machine direction, is 2.0 or less. 
     
     
         13 . The non-woven fabric according to  claim 12 , wherein a maximum strength at a time of elongation in the machine direction is 35.0 (N/25 mm) or more.