Abstract: A gel coat for a surface of a composite article contains a curable urethane acrylate resin preferably based on aliphatic polyester polyols and aliphatic polyisocyanates. The gel coat provides a surface that has high gloss and color retention after prolonged exposure to ultraviolet radiation. The gel coat composition contains resin and acrylic diluents, including optional difunctional and trifunctional diluents. The gel coat is optionally pigmented to produce an article that may be used without further surface treatment.

Abstract: A composite article is manufactured in an open tool molding process, advantageously with a mold made of a polymer material. A coating layer is applied onto the mold surface and physically deformed to provide a textured surface away from the mold prior to complete cure. Thereafter a composite material is applied onto the textured coating surface such that the composite material adjacent to textured coating surface substantially conforms to the shape of the textured coating surface. The composite article may be a gel coat material from which the coating layer is removed after de-molding to reveal a textured surface layer in the gel coat.

Abstract: A multilayer composite contains a gel coat layer, a laminate layer, and a barrier layer disposed between the gel coat and the laminate layer. The laminate contains from 40-80% by weight paste and from 20-60% by weight reinforcing fibers. The barrier coat also comprises a cured polyester resin, and contains reinforcing fibers shorter than those in the laminate layer. The barrier layer has sufficient flexibility to avoid cracking during demolding and handling. Preferably, the barrier layer exhibits an elongation at break of more than 1%, and more preferably about 2% or more. The resin of the barrier layer can contain up to about 25% by weight of the resin of an isophthalic acid based polyester resin. The composites can be made using an open tool molding process.

Abstract: Composite articles are prepared by a spray up operation. In a first step, a gel coat is applied onto a mold surface which has been optionally pretreated with a mold release coating. Next, a barrier coat is applied over the gel coat in the mold and thereafter a laminate formula is applied over the barrier coat. The laminate contains from 40-80% by weight paste and from 20-60% by weight reinforcing fibers. In a preferred embodiment, the paste comprises 90% or more by weight resin, up to 5% filler, and an initiator composition capable of initiating cure at a temperature of 50° C. or lower. In a preferred embodiment, the multilayer composite has a thickness of about 15 mm or less, and is useful as an automobile body panel. The laminate preferably comprises a low shrink, low density glass fiber filled polyester resin.

Abstract: Composite articles are prepared by a spray up operation. In a first step, a gel coat is applied onto a mold surface which has been optionally pretreated with a mold release coating. Next, a barrier coat is applied over the gel coat in the mold and thereafter a laminate formula is applied over the barrier coat. The laminate contains from 20-60% by weight reinforcing fibers. In a preferred embodiment, the multilayer composite has a thickness of about 15 mm or less, and is useful as an automobile body panel. The gel coat contains a curable polyester polyurethane acrylate resin, and the composite article has a surface that has high gloss and color retention after prolonged exposure to ultraviolet radiation. The laminate preferably comprises a low shrink, low density glass fiber filled polyester resin.

Abstract: In accordance with the teachings of the present invention, a method for producing a vehicle door is disclosed. Interior door components such as a window lift mechanism, a lock assembly, and a horizontal energy absorbing member are coupled to a door substructure. A finished exterior door panel having a class-A surface is adhesively bonded to the substructure, disposing the door interior components between the finished exterior door panel and a portion of the door substructure. The assembled door is coupled to a previously painted vehicle body.

Abstract: A balanced pressure compression molding method in which a first charge of a plastic material that will at least constitute the reinforcing means, i.e., the ribs and/or bosses, is first placed in the mold and compressed, the mold is then opened and a second charge of the plastic material is placed in the mold to constitute the flat or panel portion of the panel part after compression. A force is applied to the ejector means of the molding apparatus such that a pressure between 500 to 1500 psi is generated inside the rib sections. This force is removed before the end of the molding cycle. A plastic part having a perfect appearance surface without sink mark defects can be produced.

Abstract: A dual charge compression molding method in which a first charge of a plastic material that will at least constitute the reinforcing means, i.e., the ribs and/or bosses, is first placed in the mold and compressed, the mold is then opened and a second charge of the plastic material is placed in the mold to constitute the flat or panel portion of the panel part after compression. A plastic part having a perfect appearance surface without sink mark defects can be produced.

Abstract: A method of producing glass fiber mat reinforced plastic panels having at least one smooth appearance surface in a set of two matched mold members having interior mold surfaces defining a mold cavity contained therein of which at least one interior surface is the mirror image of the appearance surface of the panel. The method includes the steps of placing at least one layer of glass fiber mat in a mold cavity, pouring a polymeric material into the cavity saturating the glass fiber mat, closing the two mold members together with at least one layer of a flexible sheeting material disposed over and adjacent to the interior mold surface opposing the interior mold surface producing the appearance surface of the panel, clamping the two mold members together, curing the polymeric material for a sufficient time into a hard plastic panel, and opening the matched mold members and demold a finished panel having at least one smooth appearance surface.

Abstract: A method of molding and forming a laminated foamable sheet which contains a solid catalyst that is activated at the molding temperature of the laminate. A laminated foamable sheet is first provided by saturating a glass fiber mat with a urethane foam composition containing a solid catalyst of stearate salt and then sandwich it between two layers of cover sheet. The solid catalyst contained in the urethane composition cannot be activated until it is heated to the molding temperature of the laminated sheet. The laminated foamable sheet is then positioned into a mold having two heated platens and a cavity defined therein with the mold temperature set at a temperature of at least that of the melting point of the solid catalyst contained in the urethane composition. The solid catalyst in the composition melts and causes the urethane precursors to start the foaming reaction such that the laminate expands and fills the cavity of the mold.

Abstract: A method of producing a smooth surface on a premolded glass fiber reinforced plastic panel where protruding fibers would otherwise produce a rough surface. The method is practiced by coating the surface of a premolded glass fiber reinforced plastic panel maintained at or near the molding temperature with a polyurethane composition, and applying molding pressure on the coated surface to cause the coating resin to flow and fill the valleys between the protruding fibers. The molding pressure is released while the coating resin is still in its fluid state. A finished, smooth panel is made by this process which can be readily painted and used as an automotive exterior body panel. Optionally, a layer of a predecorated sheet material can first be placed in the upper mold cavity of a mold, then compressed against a premolded panel positioned in the lower mold cavity with a layer of coating resin sandwiched in between.

Abstract: A laminated foamable and moldable sheet which contains a solid catalyst that is activated at the molding temperature of the laminate.