US 4,242,406 A · Fiber reinforced composite structural laminate composed of two layers tied to one another by embedded fibers bridging both layers

Abstract

This invention relates to a structural laminate having a plastic surface finish coat laminated to a structural base which has exceptional bond strength between the structural base and the plastic layer with which it interfaces. The structural base comprises a glass reinforced gypsum layer. The plastic laminate portion comprises a plastic surface finish coat, preferably a polyester gel coat or an acrylic resin, bonded to a reinforcing layer of curable polyester or epoxy resin reinforced with glass fibers. The reinforcing layer is adhered to a bonding layer which comprises glass fibers protruding from the reinforcing layer and coated with a limited amount of organic resin such as polyester or epoxy resin. The glass reinforced gypsum layer is applied to the protruding fibers of the bonding layer to form an interface having a bond strength of at least about 150 psi as determined by ASTM C297-68.

Claims10

Dependent claims

A structural laminate comprising:

(a) a plastic surface finish coat bonded to
(b) a reinforcing layer of an organic resin selected from polyester resins and epoxy resins containing reinforcing fibers, adhered to
(c) a bonding layer of organic resin coated glass fibers which are bonded to the reinforcing layer and which protrude therefrom, said glass fibers being present in an amount sufficient to provide a surface density of 0.25 to 0.65 ounces per square foot of reinforcing layer surface area, said protruding glass fibers being coated with an amount of the organic resin sufficient to promote adhesion of the fibers to one another at their intersections, but insufficient to encapsulate the fibers so as to prevent the gypsum layer (d) from intimately surrounding and engaging a substantial portion of the individual protruding coated fibers, said coated glass fibers being engaged and surrounded by
(d) a gypsum layer reinforced with glass fibers which functions as the structural base, and said structural laminate is characterized by having a bond strength between the gypsum layer and the plastic layer with which it interfaces of at least about 150 psi as determined by ASTM C297-68.

1 more element

A process for making a structural laminate comprising:

(a) applying a curable plastic finish coat containing a catalyst therefor to the surface of a mold;
(b) partially curing said curable plastic finish coat;
(c) applying a reinforcing layer of organic resin containing reinforcing fibers to said partially cured plastic finish coat by spraying said organic resin and reinforcing fibers onto said plastic finish coat;
(d) densifying said reinforcing layer to remove entrapped air;
(e) while said reinforcing layer is tacky, applying a bonding layer of chopped glass fibers by dry spraying said glass fibers onto said reinforcing layer in such a manner that said glass fibers protrude from said reinforcing layer;
(f) applying a light mist organic resin coating by spraying a limited amount of catalyzed resin over the surface of the protruding glass fibers;
(g) allowing the organic resin coating on the protruding glass fibers and the organic resin of the reinforcing layer to cure to at least the gel state;
(h) applying a neat coat of plaster containing no glass fibers by spraying the plaster onto the protruding glass fibers;
(i) applying a layer of glass reinforced plaster onto the protruding fibers by simultaneously spraying the plaster and operating a glass chopper to supply a stream of chopped glass fibers into the wet plaster;
and
(j) drying the plaster to form a hard gypsum structural base.

8 more elements

Dependencies are inferred from the claim text.

Fiber reinforced composite structural laminate composed of two layers tied to one another by embedded fibers bridging both layers

Life of this patent

Fiber reinforced composite structural laminate composed of two layers tied to one another by embedded fibers bridging both layers

Life of this patent

Abstract

Claims10