Manufacturing method and manufacturing appartus of an absorbent body

Abstract

A manufacturing method of an absorbent body used for an absorbent article, includes molding the absorbent body by sucking in a gas, mixed with a liquid absorbent fiber and a superabsorbent polymer, using a suction hole at a bottom portion of a mold, and laminating the liquid absorbent fiber and the superabsorbent polymer on the bottom portion, and making a lamination thickness of the absorbent body thin by sucking out gas in the absorbent body placed on a placement surface on which the absorbent body is placed by, after the molding, in a state in which the gas is not supplied, sucking air through the suction hole on the placement surface, and creating an air pressure, in a space in between fibers in the absorbent body while sucking out the air, lower than that in a space in between fibers in the absorbent body while laminating in molding.

1 . A manufacturing apparatus of an absorbent body used for an absorbent article, the apparatus comprising:
 a first apparatus that molds the absorbent body by sucking in a gas mixed with a liquid absorbent fiber and a superabsorbent polymer from a suction hole at a bottom portion of the mold, and laminating the liquid absorbent fiber and the superabsorbent polymer on the bottom portion; and   a second apparatus that makes a lamination thickness of the absorbent body thin by sucking in air in the absorbent body placed on a placement surface on which the absorbent body is placed by,   in a state in which the gas is not supplied, sucking in the air from the suction hole on the placement surface, and making an air pressure in a space in between fibers in the absorbent body while sucking in the air lower than an air pressure in a space in between fibers in the absorbent body while laminating in molding.   
     
     
         2 . A manufacturing apparatus of an absorbent body used for an absorbent article according to  claim 1 , wherein
 the second apparatus includes a covering member that opposes the placement surface and that covers the absorbent body from an opposite side of the placement surface, and   inflow of an outside air into the absorbent body is suppressed by the placement surface and the covering member.   
     
     
         3 . A manufacturing apparatus of an absorbent body used for an absorbent article according to  claim 2 , wherein
 the covering member is arranged in a non-contacting manner with the absorbent body.   
     
     
         4 . A manufacturing apparatus method of an absorbent body used for an absorbent article according to  claim 2 , wherein
 the absorbent body is transported by the placement surface moving along a predetermined travel path,   the covering member is a belt member, and   at least while making the lamination thickness thin, the belt member moves in the travel path together with the movement of the placement surface.   
     
     
         5 . A manufacturing apparatus of an absorbent body used for an absorbent article according to  claim 4 , wherein
 the placement surface is a portion of a predetermined surface included in a predetermined member,   the predetermined surface has width direction intersecting with a direction along the travel path, and   the belt member closely contacts with a portion to an outer side in the width direction than the placement surface of the predetermined surface, in a range in which the belt member moves in the travel path together with the movement of the placement surface.   
     
     
         6 . A manufacturing apparatus of an absorbent body used for an absorbent article according to  claim 2 , wherein,
 the first apparatus has the mold formed in a concave shape on an outer circumferential face,   the first apparatus molds the absorbent body by using a first rotating drum that continuously rotates in one direction of a circumferential direction, a supply duct provided in a predetermined position in the circumferential direction and that supplies a gas with the liquid absorbent fiber and the superabsorbent polymer mixed therein toward the outer circumferential face, and a mold release mechanism that releases the absorbent body from the mold and that is provided to a downstream side than the predetermined position in the circumferential direction,   the placement surface in accordance with the lamination thickness thin is the bottom section of the mold, and   the coving member is arranged opposing the outer circumferential face in a position between the supply duct and the mold release mechanism in the circumferential direction of the first rotating drum.   
     
     
         7 . A manufacturing apparatus of an absorbent body used for an absorbent article according to  claim 2 , wherein
 the first apparatus has the mold formed in a concave shape on an outer circumferential face,   the first apparatus molds the absorbent body by suing a first rotating drum that continuously rotates in one direction of a circumferential direction, and a supply duct provided in a predetermined position of the circumferential direction and that supplies a gas with the liquid absorbent fiber and the superabsorbent polymer mixed therein toward the outer circumferential face, and   in making the lamination thickness thin,   includes a second rotating drum provided to a downstream side than the predetermined position in the circumferential direction, and that receives the absorbent body from the mold of the first rotating drum,   the placement surface in accordance with making the lamination thickness thin is a portion of an outer circumferential face of the second rotating drum, and the second rotating drum rotates in one direction of a circumferential direction, while the placement surface holds the absorbent body received from the first rotating drum on the outer circumferential face, with a suction air from a suction hole on the holding surface, and   the covering member is arranged in a predetermined position in the circumferential direction, while opposing the outer circumferential face of the second rotating drum.   
     
     
         8 . A manufacturing apparatus of an absorbent body for an absorbent article according to  claim 7 , wherein
 the outer circumferential face of the second rotating drum is formed into a substantially smooth surface without a recessed portion that has a depth deeper than a lamination thickness of the absorbent body when receiving the absorbent body from the first rotating drum,   the covering member is a belt member opposing the circumferential face of the second rotating drum and arranged in a predetermined position in the circumferential direction, and   the belt member moves along the outer circumferential face together with the movement of the placement surface, at least while making the lamination thickness thin, and the belt member is sucked toward the outer circumferential face with the suction air from the suction hole and sandwiches and presses the absorbent body with the placement surface on the outer circumferential face.   
     
     
         9 . A manufacturing apparatus of an absorbent body used for an absorbent article according to  claim 1 , wherein
 the placement surface is formed on one side of a moving member that moves along a predetermined travel path, and on an opposite surface of the placement surface of the moving member is oppositely positioned a space that performs suction of the air from the suction hole on the placement surface,   the space is defined into a plurality of zones along the travel path, and a covering member that opposes the placement surface and covers the absorbent body from an opposite side of the placement surface is arranged, in a predetermined range of the travel path,   an air pressure of a zone corresponding to the predetermined range of the plurality of zones is lower than that of a zone corresponding to a position to a downstream side than the predetermined range, and   an air pressure of a zone corresponding to a downstream end in the predetermined range is set to a value between   an air pressure of a zone other than a zone corresponding to the downstream end of the zones corresponding to the predetermined range and   an air pressure of a zone corresponding to a position to a downstream side than the predetermined range.