초록 ▼

Method for making a molded resin-impregnated fibrous article having relatively dense surface layers separated by a less dense region. The article is made by disposing curable resin-impregnated compressible fibrous layers in a mold cavity the layers being separated by a medium which is collapsible by

Method for making a molded resin-impregnated fibrous article having relatively dense surface layers separated by a less dense region. The article is made by disposing curable resin-impregnated compressible fibrous layers in a mold cavity the layers being separated by a medium which is collapsible by heat before impregnating resin cures in fiber regions adjacent said medium. Upon heating, the collapsible medium shrinks or is absorbed and the adjacent fibrous material expands to fill the space left by the collapsing medium.

대표청구항 ▼

A method for producing as a porous molded end product, a member adapted to serve as a thermal and/or acoustic barrier and having improved thermal and/or acoustic properties comprising the steps of: compressing a plurality of porous resilient compressible blankets of loosely gathered fibers treated w

A method for producing as a porous molded end product, a member adapted to serve as a thermal and/or acoustic barrier and having improved thermal and/or acoustic properties comprising the steps of: compressing a plurality of porous resilient compressible blankets of loosely gathered fibers treated with an uncured binder within a closed mold having a shape conforming to the desired configuration of the molded end product; interposing a collapsible medium formed of thermoplastic material and having a predetermined thickness between adjacent ones of said blankets, said medium occupying a predetermined region of said mold whereby said mold compresses a major portion of said blankets by a substantial amount and only slightly compresses an associated portion of said medium; heating said mold to develop a varying temperature profile across the interior of said mold to thereby heat said blankets and said medium, the temperature level in the region of said medium being such that said medium initially softens and contracts significantly and ultimately disperses into the interstices of said blankets while the binder adjacent to the region of said medium is uncured allowing adjacent uncured resilient portions of said compressed blankets to correspondingly expand into the region previously occupied by the contracting medium while portions of said blankets remote from said medium are being cured, said uncured binder ultimately being cured to thereby create a porous end product which gradually decreases in density from both major surfaces toward the center thereof.