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

• US 4,242,406 A
• Filed: 04/30/1979
• Issued: 12/30/1980
• Est. Priority Date: 04/30/1979
• Status: Expired due to Term

• Current Assignee: United States Gypsum Company (GEBR Knauf Verwaltungsgesellschaft KG), PPG Industries Incorporated (Nouryon BV)
• Original Assignee: United States Gypsum Company (GEBR Knauf Verwaltungsgesellschaft KG), PPG Industries Incorporated (Nouryon BV)
• Inventors: Fitzpatrick, Thomas J., Hoffman, Robert M., Knoll, Wayne M., El Bouhnini, Larbi, Harwick, Donald M.
• Primary Examiner(s): Cannon, James C.
• Application Number:
  US06/034,695
• Time in Patent Office: 610 Days
• Field of Search: 264/171, 264/258, 264/309, 264/337, 52/309.13, 52/309.14, 52/309.15, 52/454, 52/612, 156/39, 156/42, 156/44, 428/236, 428/246, 428/268, 428/284, 428/285, 428/272, 428/286, 428/287, 428/414, 428/302, 428/415, 428/417, 428/431, 428/432, 428/482, 428/483, 428/500, 428/521
• US Class Current: 442/373
• CPC Class Codes: B28B 1/522 for producing multi-layered articles B28B1/526, B28B1/527 take precedence
• CPC Class Codes: B29C 37/0082 Mechanical anchoring B29C66/303 takes precedence
• CPC Class Codes: B29C 70/00 Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
• CPC Class Codes: B29K 2309/08 Glass
• CPC Class Codes: E04C 2/26 composed of materials covered by two or more of groups E04C2/04, E04C2/08, E04C2/10 or of materials covered by one of these groups with a material not specified in one of the groups of cement and mineral fibres E04C2/04
• CPC Class Codes: Y10T 428/24994 Fiber embedded in or on the surface of a polymeric matrix
• CPC Class Codes: Y10T 428/31515 As intermediate layer
• CPC Class Codes: Y10T 428/31518 Next to glass or quartz
• CPC Class Codes: Y10T 428/31525 Next to glass or quartz
• CPC Class Codes: Y10T 428/3162 Cross-linked polyester [e.g., glycerol maleate-styrene, etc.]
• CPC Class Codes: Y10T 428/31794 Of cross-linked polyester
• CPC Class Codes: Y10T 428/31797 Next to addition polymer from unsaturated monomers
• CPC Class Codes: Y10T 428/31855 Of addition polymer from unsaturated monomers
• CPC Class Codes: Y10T 428/31931 Polyene monomer-containing
• CPC Class Codes: Y10T 442/651 Plural fabric layers
• CPC Class Codes: Y10T 442/652 Nonwoven fabric is coated, impregnated, or autogenously bonded

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.

Claims

1. 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.

2. A structural laminate in accordance with claim 1 in which the plastic surface finish coat is selected from the group consisting of polyester resins, acrylic resins and acrylonitrile-butadiene-styrene resins and the reinforcing layer comprises a polyester resin.

3. A structural laminate in accordance with claim 1 in which the plastic surface finish coat is an epoxy resin, the reinforcing layer comprises an epoxy resin and the glass fibers comprising the bonding layer are mist coated with a polyester resin.

4. A structural laminate in accordance with claim 2 in which the glass fibers comprising the bonding layer are mist coated with a polyester resin.

5. A structural laminate in accordance with claim 1 in which the reinforcing fibers in the reinforcing layer are selected from chopped glass roving, glass strand mat, inorganic fibers and organic fibers.

6. 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.

7. A process in accordance with claim 6 in which the curable plastic finish coat is a polyester resin, the organic resin of the reinforcing layer and the organic resin applied to the protruding glass fibers are both polyester resins, and the chopped glass fibers comprising the bonding layer are present in an amount to provide surface density of 0.65 ounces per square foot of reinforcing layer surface area.

8. A process in accordance with claim 6 in which the curable plastic finish coat is an epoxy resin, the organic resin of the reinforcing layer and the organic resin applied to the protruding glass fibers are both epoxy resins, and the chopped glass fibers comprising the bonding layer are present in an amount to provide a surface density of 0.25 to 0.65 ounces per square foot of reinforcing layer surface area.

9. A process for making a structural laminate comprising

(a) applying a reinforcing layer of polyester resin containing reinforcing fibers to a shell material selected from an acrylic resin and an acrylonitrile-butadiene-styrene resin by spraying said polyester resin and reinforcing fibers onto the interior surface of said shell material;

(b) densifying said reinforcing layer to remove entrapped air;

(c) 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;

(d) applying a light mist of polyester resin coating by spraying a limited amount of catalyzed polyester resin over the surface of the protruding glass fibers;

(e) allowing the polyester resin coating on the protruding glass fibers and the polyester resin of the reinforcing layer to cure to at least the gel state;

(f) applying a neat coat of plaster containing no glass fibers by spraying the plaster onto the protruding glass fibers;

(g) 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

(h) drying the plaster to form a hard gypsum structural base.

10. A process in accordance with claim 9 in which the chopped glass fibers comprising the bonding layer are present in an amount to provide a surface density of 0.25 to 0.65 ounces per square foot of reinforcing layer surface.