초록 ▼

A method for producing a porous plastic molded product of uniform, predictable porosity throughout. A fluidized airstream of moldable plastic powder is formed. Water may be injected into said fluidized powder airstream for maintaining said powder in a uniform, fluidized dispersion. The moisturized,

A method for producing a porous plastic molded product of uniform, predictable porosity throughout. A fluidized airstream of moldable plastic powder is formed. Water may be injected into said fluidized powder airstream for maintaining said powder in a uniform, fluidized dispersion. The moisturized, fluidized, powder airstream is injected into a cavity of a closed mold to fill said mold cavity with said powder. The mold is maintained at a temperature and for a time sufficient to at least partially fuse said powder particles together without melting said particles, thereby to form a porous, plastic molded product. The mold is partially separated for cooling the product which is then discharged from the mold. The product may be further cured by heating the molded product in an oven at a temperature and for a time sufficient to cure said molded product without melting said plastic or glazing said product.

대표청구항 ▼

A method of producing a porous plastic molded product of predictable porosity throughout, comprising the steps of forming a fluidized stream of ultra-high-molecular-weight moldable-plastic powder solid particles and air; injecting said fluidized powder airstream into a cavity of a closed mold, compo

A method of producing a porous plastic molded product of predictable porosity throughout, comprising the steps of forming a fluidized stream of ultra-high-molecular-weight moldable-plastic powder solid particles and air; injecting said fluidized powder airstream into a cavity of a closed mold, composed of mating portions which define said cavity when mutually closed together and which confines said powder within its interior, to fill said mold cavity with said powder while said airstream leaves said cavity through means for escape of said air while precluding flow of said particles from said cavity; maintaining said mold at a temperature and for a time sufficient to fuse or sinter said powder particles together, in situ within said mold, without needing the imposition upon said powder of any molding pressure beyond that developed by said injecting in order to fuse or sinter said particles, without opening said portions apart and without melting said particles, thereby to form a porous plastic molded product of uniform predictable porosity and the exterior of which has a determined size and shape defined by and conformed to the shape and size of said interior; and subsequently discharging said porous plastic molded product from said mold without first having to have cooled said mold.