Seat cushion, and method for manufacturing same

A method for producing a seat cushion comprising a three-dimensional filaments-linked structure of a thermoplastic resin or a thermoplastic elastomer, the method comprising:

• a molten filament supplying step of discharging a plurality of molten filaments of a thermoplastic resin or a thermoplastic elastomer downward in a thermal vertical direction from a plurality of nozzle holes,
• a three-dimensional filaments fused body forming step of fusion-bonding contact points between the plurality of molten filaments while three-dimensionally entangling the molten filaments to form a three-dimensional filaments fused body, and
• a three-dimensional filaments-linked structure forming step of cooling and solidifying the three-dimensional filaments fused body while drawing the three-dimensional filaments fused body with an underwater drawing machine arranged in cooling water, to thereby form a three-dimensional filaments-linked structure,
• the three-dimensional filaments-linked structure forming step including a three-dimensional filaments-linked structure density controlling step of controlling a density of the three-dimensional filaments fused body by varying a drawing speed of the underwater drawing machine,
• the drawing speed of the underwater drawing machine being varied, based on a standard upper body weight and a standard width of buttocks of a group of humans who are to use the seat cushion, and a drawing speed of the underwater drawing machine in an area for producing a seat surface left-right direction central part corresponding to the standard width of buttocks being higher than a drawing speed of the underwater drawing machine in areas for producing both seat surface left-right direction end parts outside the standard width of buttocks.