Method of making a composite rigid foamed chair seat or the like

Claim 1

A method for making composite rigid foamed article such as a chair seat or the like, said method comprising: (a) attaching a rigid insert to the first half of a mold with a sheet of air permeable material sandwiched therebetween, said rigid insert being of the general shape of, but smaller than, the article to be produced in order to allow the forming of a resin material around the insert without the insert showing on the finished side of the design and with the design providing for maximum strength contribution from the insert, and said rigid insert and said first half of the mold having said sheet of air permeable material extending from between them outward past the edges of the first half of the mold said sheet of air permeable material having a sufficiently porous structure to allow a gas to pass therethrough even when the material is under compression; (b) introducing a liquid foamable resin reaction mixture into the cavity of a second half of a mold said mixture being capable of foaming and curing to form a rigid supporting form, and said cavity being of the shape of the article being produced; (c) placing the two mold halves together with the air permeable material extending from the cavity of the mold to the exterior thereof thereby forming a passage way for reaction gases to leave the mold; (d) permitting said liquid foamable resin reaction to foam and cure and form a rigid hard cellular structure throughout while expanding around the sides of the rigid insert while at the same time preventing the resin from binding to the air permeable material, and while allowing expansion and reaction gases to pass from the mold by passing through the passageway created by the air permeable material; and (e) removing the finished article from the mold.

Claim 2

A method for making composite rigid foamed article such as a chair seat or the like, said method comprising: (a) attaching a rigid insert to the first half of a mold with a sheet of air permeable material sandwiched therebetween, said rigid insert being of the general shape of, but smaller than, the article to be produced in order to allow the forming of a resin material around the insert without the insert showing on the finished side of the design and with the design providing for maximum strength contribution from the insert, and said rigid insert and said first half of the mold having said sheet of air permeable material extending from between them outward past the edges of the first half of the mold said sheet of air permeable material having a sufficiently porous structure to allow a gas to pass therethrough even when the material is under compression; (b) introducing a liquid foamable resin reaction mixture into the cavity of a second half of a mold said mixture being capable of foaming and curing to form a rigid supporting form, and said cavity being of the shape of the article being produced; (c) placing the two mold halves together with the air permeable material extending from the cavity of the mold to the exterior thereof thereby forming a passage way for reaction gases to leave the mold; (d) permitting said liquid foamable resin reaction to foam and cure and form a rigid hard cellular structure throughout while expanding around the sides of the rigid insert while at the same time preventing the resin from binding to the air permeable material, and while allowing expansion and reaction gases to pass from the mold by passing through the passageway created by the air permeable material; and (e) removing the finished article from the mold.