Method of forming a composite component

A composite component such as a seat back for a vehicle comprises a support portion and at least one reinforcing composite layer. The support portion comprises a thermoplastic material and the reinforcing composite layer comprises a polymeric material impregnating a plurality of fibers. The polymeric material of the reinforcing composite layer is integrated with the thermoplastic of the support portion. A method of forming the composite component includes placing the composite layer into a mold, heating the thermoplastic material to a molten state, and disposing the thermoplastic material in the molten state into contact with the composite layer. The method further includes promoting interaction between the thermoplastic material and the polymeric material to integrate the support portion and the reinforcing composite layer. The thermoplastic material supports the reinforcing composite layer and the reinforcing composite layer reinforces the thermoplastic material to prevent failure when subjected to a load.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention is related to a composite component including a support portion and a reinforcement composite layer and a method of forming the same.

2. Description of the Related Art

A composite component is formed of at least two diverse materials that are combined together to form a single unit. Composite components are used in a variety of settings including seat backs for a vehicle and structural beams. Seat backs for vehicles are assembled in a seat assembly and the seat assembly is disposed in the vehicle, such as an automobile, for supporting occupants of the vehicle.

Seat backs must meet structural requirements by having sufficient stiffness to support repeated loads commonly exerted on the seat back such as loads exerted by passengers. Seat backs must also have sufficient impact strength to withstand cracking or breaking during impacts such as impacts created by cargo moving in the vehicle and occupant loads during crash events. For example, cargo may move in the vehicle if the cargo is not secured and the vehicle is involved in an accident.

As such, the seat back is generally formed from metal such as steel. Steel meets the structural requirements by providing sufficient stiffness and sufficient impact strength to satisfy the above mentioned concerns. However, the steel seat back is comprised of several individual components and the assembly of these components makes such a construction relatively expensive. Additionally, steel is a relatively heavy material. Generally in vehicles, heavy material such as steel is avoided, where possible, in favor of lighter materials. With respect to the seat back, replacing heavy material with lighter material increases fuel economy of the vehicle. In addition, lighter material is more easily handled in the assembly process of the seat back and the assembly process of the vehicle.

It is known in the art to form the seat back from a relatively light material such as plastic. Plastic is beneficial in such an application not only because plastic is lighter than steel, but also because seat back features may be integrated into the frame portion made of plastic. Such seat back features include headrest guides that are integrally formed on the frame portion during an injection molding process. Also, plastic has the benefit of being able to produce a seat back in a single injection molded process.

However, the use of plastic in such applications is limited due to the relatively low stiffness and low impact strength of plastic in comparison to steel. Seat backs made of plastic must be thicker than those made of steel to achieve sufficient stiffness and impact strength. As a result, seat backs made from plastic may be too thick to accommodate packaging constraints in vehicles.

It is known in the art to form seat backs from composite materials to increase the stiffness and impact strength of the seat back. An example of such a seat back includes a plastic support portion and a metal reinforcing portion attached to the support portion for reinforcing the support portion. Adequate interaction between the plastic of the support portion and the metal of the reinforcement portion is difficult to obtain. In addition, further weight reduction could be obtained by replacing the metal reinforcement portion with a lighter material. Further, such a seat back is not easily recyclable because the seat back is formed of both plastic and metal.

Accordingly, it would be desirable to manufacture a composite component such as a seat back having the relatively light weight and the capability of integration of features as provided by the plastic while also having sufficient stiffness and impact strength without significantly increasing the thickness of the seat back. It would also be desirable to manufacture a composite component which is easily recyclable. Further, it would also be desirable to establish a method of increasing the stiffness and the impact strength of the composite component while also improving the interaction between the materials of the composite component.

SUMMARY OF THE INVENTION AND ADVANTAGES

The present invention is a composite component. The composite component comprises a support portion comprising a thermoplastic material and presents a connecting end. At least one reinforcing composite layer abuts the connecting end of the support portion. The at least one reinforcing composite layer comprises a polymeric material and a plurality of fibers impregnated in the polymeric material. The polymeric material presents a connecting portion of the at least one reinforcing composite layer integrated with the connecting end of the support portion.

The present invention also includes a method of forming the composite component including the support portion comprising the thermoplastic material and the reinforcing composite layer including at least one composite reinforcing layer comprising the polymeric material and the plurality of fibers impregnated in the polymeric material. The method comprises placing the composite layer into a mold. The method further includes heating the thermoplastic material to a molten state and disposing the thermoplastic material in the molten state into contact with the reinforcing composite layer. The method further includes promoting interaction between the thermoplastic material of the support portion and the polymeric material of the composite layer to integrate the support portion and the reinforcing composite layer.

Accordingly, the thermoplastic material that forms the connecting end of the support portion is integrated with the polymeric material that forms the connecting portion of the reinforcing composite layer. The combination of the thermoplastic material and the reinforcing composite layer results in an advantageous combination with the thermoplastic material supporting the reinforcing composite layer and with the reinforcing composite layer reinforcing the thermoplastic material. Specifically, the thermoplastic material of the support portion by itself may be subject to failure when subjected to a load and the reinforcing composite layer by itself is subject to failure when subjected to a load. When the thermoplastic material and the reinforcing composite layer are integrated with each other, the thermoplastic material supports the reinforcing composite layer and the reinforcing composite layer reinforces the thermoplastic material to prevent failure when subjected to a load.

Further, the reinforcing composite layer is relatively light compared to the prior art thereby decreasing the weight of the composite component. In addition, the thermoplastic material of the support portion and the polymeric material of the reinforcing composite layer are easily integrated with each other to combine the support portion and the reinforcing composite layer into a single unit. Further, due to the types of materials used to form the composite component, the composite component is easily recyclable because the thermoplastic material and the reinforcing composite layer are recyclable together thereby eliminating any need to separate diverse materials that are not recyclable together.

DETAILED DESCRIPTION OF THE INVENTION

Referring to the Figures, wherein like numerals indicate corresponding parts throughout the several views, a composite component, is shown generally at20. It should be appreciated that the composite component20may be any type of composite component20for a variety of uses. For example, the composite component20may be a seat back22or a structural beam (not shown). In the embodiments shown in the Figures, the composite component20is the seat back22for a vehicle, such as an automobile. The seat back22is assembled in a seat assembly (not shown) including a seat bottom extending generally horizontally for supporting a seated passenger or cargo. It should be appreciated that the seat back22may be used in any type of vehicle including, for example, a bus, an airplane, and a boat. Although not required, the seat back22typically includes foam surrounding the support portion24and the reinforcing composite layer26and a covering over the foam.

As shown inFIGS. 1-3 and 8A-C, the composite component20includes a support portion24and at least one reinforcing composite layer26. As described additionally below, the composite component20may have more than one reinforcing composite layer26. The support portion24comprises a thermoplastic material and the reinforcing composite layer26is integrated with the thermoplastic material of the support portion24. In other words, as will be discussed below, the support portion24and the reinforcing composite layer26are mounted to each other to form a single unit. The reinforcing composite layer26is thin relative to the support portion24. Each of the reinforcing composite layers26may be approximately 0.1 to 0.5 mm thick.

As best shown inFIGS. 5A-C, the reinforcing composite layer26comprises a polymeric material and a plurality of fibers28impregnated in the polymeric material. The reinforcing composite layer26may be integrated with the thermoplastic material in a variety of ways. For example, the reinforcing composite layer26may be in the form of a continuous fiber reinforced mat that is preformed and subsequently integrated with the thermoplastic material. An example of such a continuous fiber reinforced mat is that which is commercially available from Baycomp Canada in Burlington, Ontario, Canada under the tradename CFRT. Alternatively, for example, the plurality of fibers28and the polymeric material are simultaneously integrated with the thermoplastic material.

As best shown inFIGS. 8A-C, the support portion24presents a connecting end32and the reinforcing composite layer26abuts the connecting end32of the support portion24. Specifically, the polymeric material defines a connecting portion34of the reinforcing composite layer26and the connecting portion34is integrated with the connecting end32of the support portion24. The polymeric material of the reinforcing composite layer26is integrated with the thermoplastic material of the support portion24to attach the reinforcing composite layer26and the support portion24to each other.

The combination of the thermoplastic material of the support portion24and the reinforcing composite layer26attached to each other results in an advantageous combination. Specifically, the thermoplastic of the support portion24by itself may fracture when subjected to a load. The reinforcing composite layer26may buckle and/or fracture when subjected to a load. When the thermoplastic material and the reinforcing composite layer26are integrated with each other, the thermoplastic material supports the reinforcing composite layer26to prevent buckling and/or fracturing of the reinforcing composite layer26, i.e., to provide torsional stiffness, and the reinforcing composite layer26reinforces the thermoplastic material to prevent fracturing of the thermoplastic material under a load. In other words, the reinforcing composite layer26provides increased stiffness and impact strength to the composite component20.

Preferably the thermoplastic material is of the type capable of being injection molded such that the thermoplastic material may be molded into variety of configurations and shapes. As known to one skilled in the art, plastic injection molding is performed by heating the thermoplastic material such that the thermoplastic material is in a molten state and injecting the thermoplastic material into a mold66, and more specifically, an injection mold36. For example, the injection mold36is shown schematically inFIG. 7. The thermoplastic material is then cooled to solidify the thermoplastic material and the thermoplastic material is thereafter removed from the injection mold36. The thermoplastic material is preferably of the type that produces a net-shaped product resulting from injection molding. As known to one skilled in the art, the net-shaped product is defined as a product of injection molding that is finished when removed from the injection mold36. In other words, the composite component20is finished and requires no secondary finishing operations after removal from the injection mold36.

For example, the thermoplastic material of the support portion24comprises a first nylon. Specifically, for example, the nylon is fiber reinforced nylon and an example of such fiber reinforced nylon is a glass fiber reinforced nylon that is commercially available from BASF Corporation in Florham Park, N.J. under the tradename Ultramid® TG7S PA6. It should be appreciated that the support portion24may be formed from any type of suitable thermoplastic material, reinforced or not, without departing from the nature of the present invention.

The polymeric material of the reinforcing composite layer26typically comprises a second thermoplastic material different than the thermoplastic material of the support portion24. In one embodiment, the second thermoplastic material is a second nylon different than the first nylon of the support portion24. Alternatively, the first nylon of the support portion24and the second nylon of the reinforcing composite layer26are the same type of material. It should be appreciated that the polymer may be a thermoset material without departing from the nature of the present invention.

As best shown inFIGS. 8A and 8B, the connecting end32of the support portion24is melt bonded to the connecting portion34of the reinforcing composite layer26. In such a configuration, preferably the second thermoplastic material of the reinforcing composite layer26has a lower melting temperature than the thermoplastic of the support portion24. Specifically, the thermoplastic material of the support portion24has a first melting temperature and the second thermoplastic material of the reinforcing composite layer26has a second melting temperature with the first melting temperature greater than the second melting temperature. For example, the first melting temperature is 560-600° F. and the second melting temperature is 400-560° F.

In the configuration where the connecting end32is melt bonded to the connecting portion34, the integration of the connecting end32and the connecting portion34preferably extends along a relatively long uninterrupted interface. This uninterrupted interface increases the strength of the integration between the connecting end32and the connecting portion34.

In the configuration where the connecting end32is melt bonded to the connecting portion34, preferably the thermoplastic material of the support portion24and the second thermoplastic material of the reinforcing composite layer26are compatible such that the thermoplastic material and the second thermoplastic material melt together and integrate with one another.

In one configuration, the composite component20includes a polyurethane layer dispose between the thermoplastic material of the support portion24and the reinforcing composite layer26. In such a configuration, the polyurethane is selected to have properties such that the polyurethane layer is conducive to melt bonding with both the thermoplastic material of the support portion24and the polymeric material of the reinforcing composite layer26. Such a configuration increases the range of materials from which the thermoplastic material and the polymeric material may be selected from because in such a configuration the thermoplastic material and the polymeric material are not required to be melt bondable to each other but rather to the polyurethane layer.

As best shown inFIG. 8C, in the alternative or in addition to melt bonding, the connecting end32of the support portion24is mechanically interlocked with the connecting portion34of the reinforcing composite layer26. Specifically, the connecting portion34of the reinforcing composite layer26defines a hole38and the connecting end32of the support portion24is further defined as a plug40extending through and engaging the reinforcing composite layer26through the hole38.

As best shown inFIGS. 5A-C, preferably the plurality of fibers28is further defined as a plurality of continuous fibers30as opposed to discontinuous fibers, i.e., short fibers. The continuous fibers30are elongated such that stress on the reinforcing composite layer26is transmitted from the polymeric material to the continuous fibers30such that the continuous fibers30reinforce the polymeric material. In other words, the stress is transferred to the continuous fibers30such that the polymeric material does not deform around the continuous fibers30when the reinforcing composite layer26is subjected to a load. The continuous fibers30impregnated and uniformly coated with the polymeric material. For example, the continuous fibers30each extend in generally the same direction and extend along a length of the reinforcing composite layer26. In the configuration where the reinforcing composite layer26comprises continuous fibers30, the reinforcing composite layer26by itself is flexible about an axis extending along the continuous fibers30and is subject to buckling when subjected to a load. The support portion24supports the reinforcing composite layer26to prevent flexing about the axis and to prevent buckling when subjected to a load. It should be appreciated that, alternatively, the plurality of fibers28are discontinuous, i.e., short fibers. In the configuration where the plurality of fibers28are discontinuous, the polymeric material deforms around the fibers28and little stress is transferred from the polymeric material to the fibers28.

Whether continuous, discontinuous, or otherwise, each of the plurality of fibers28preferably extend generally in the same direction. Alternatively, the plurality of fibers may extend in different directions or may be woven, i.e., interlaced with each other. The plurality of fibers28of the reinforcing composite layer26are preferably glass fibers. Alternatively, the plurality of fibers28are carbon fiber; however, it should be appreciated that the fiber28may be of any type known to one skilled in the art.

As best shown inFIGS. 5A-C, preferably the composite component20includes a plurality of reinforcing composite layers42. In such a configuration, preferably each of the plurality of reinforcing composite layers42are integrally stacked upon each other forming a single stack48. The stiffness and impact strength of the composite component20is increased with the addition of each reinforcing composite layer42. The plurality of reinforcing composite layers42forming the single stack48may have a total thickness of approximately 1 to 2 mm.

The plurality of reinforcing composite layers42may include any combination of reinforcing composite layers26having continuous or discontinuous fibers. For example, the plurality of reinforcing composite layers42may include a plurality of reinforcing composite layers42having the continuous fibers30, a plurality of reinforcing composite layers42having woven fibers, or a combination of at least one reinforcing composite layer26having continuous fibers30and at least one reinforcing composite layer26having woven fibers.

In the configuration where the composite component20includes the plurality of reinforcing composite layers42, the material of the fibers28of each reinforcing composite layer26may be the same as or different than the fibers28of each of the other reinforcing composite layers26. For example, the fibers28of each of the reinforcing composite layers26may be glass fibers, the fibers28of each of the reinforcing composite layers26may be carbon fibers, or the plurality of reinforcing composite layers42may include a combination of one or more reinforcing composite layers26having glass fibers and one or more reinforcing composite layers26having carbon fibers.

As shown inFIGS. 5A-C, in the configuration where each of the composite layers26has continuous fibers30, preferably at least a first reinforcing composite layer44is oriented with the continuous fibers30extending in a first direction D and at least a second reinforcing composite layer46is oriented with the continuous fibers30extending angularly relative to the first direction D. In other words, the plurality of reinforcing composite layers42may be arranged such that the fibers28of at least one reinforcing composite layer26extend angularly relative to the fibers28of other reinforcing composite layers26. Alternatively, the plurality of reinforcing composite layers42may be arranged such that the continuous fibers30of each reinforcing composite layer42extends in parallel with the fibers28of the other reinforcing composite layers26.

Several configurations of the plurality of reinforcing composite layers42are shown inFIGS. 5A-C. Specifically,FIG. 5Ashows an exploded view of a configuration of the plurality of reinforcing composite layers42including six reinforcing composite layers26each having continuous fibers30. Moving upwardly from the bottom in the configuration shown inFIG. 5A, one reinforcing composite layer26has fibers28extending in the first direction D, the next reinforcing composite layer26has fibers28extending generally at 90° relative to the first direction D, the next two reinforcing composite layers26each have fibers28extending generally along the first direction D, the next reinforcing composite layer26has fibers28extending generally at 90° relative to the first direction D, and the next reinforcing composite layer has fibers28extending along the first direction D.

FIG. 5Bshows an exploded view of another configuration of the plurality of reinforcing composite layers42including six reinforcing composite layers26each having continuous fibers30. Moving upwardly from the bottom in the configuration shown inFIG. 5B, two reinforcing composite layers26each have fibers28extending in the first direction D, the next two reinforcing composite layers26each have fibers28extending generally at 90° relative to the first direction D, and the next two reinforcing composite layers26each have fibers28extending generally in the first direction D.

FIG. 5Cshows an exploded view of another configuration of the plurality of reinforcing composite layers42including seven reinforcing composite layers26each having continuous fibers30. Moving upwardly from the bottom in the configuration shown inFIG. 5C, three reinforcing composite layers26each have fibers28extending in the first direction D, the next reinforcing composite layer26has fibers28extending at 90° relative to the first direction D, and the next three reinforcing composite layers26each have fibers28extending in the first direction D.

As shown inFIGS. 1-3 and 8A-C, the support portion24defines ribs25and the ribs25present the connecting end32. The reinforcing composite layer26defines a cavity50and the ribs25are disposed in the cavity50. Specifically, the reinforcing composite layer26is concave with a base52and a pair of sides54. Each of the pair of sides54is spaced from the other and extend from the base52defining the cavity50therebetween. As best shown inFIGS. 8A-C, the reinforcing composite layer26is U-shaped. The ribs25extend between and are integrated with the pair of sides54and the base52.

As shown inFIG. 8B, the support portion24includes a thermal mass abutting the reinforcing composite layer26. It should be appreciated that the thermal mass is disposed at an interface of the support portion24and the reinforcing composite layer26and, as shown inFIG. 8B, the ribs25include the thermal mass56abutting the reinforcing composite layer26. As will be discussed below, in the configuration where the support portion24is melt bonded to the reinforcing composite layer26, the thermal mass56heats the reinforcing composite layer26for melting the polymeric material reinforcing composite layer26.

With respect to the seat back22as shown inFIGS. 1-3, the seat back22includes a second support portion58spaced from the support portion24and another reinforcing composite layer59integrated with the second support portion58. The second support portion58comprises the same type of thermoplastic material as the support portion24and the another reinforcing composite layer59comprises the same type of material as the reinforcing composite layer26. Typically, the second support portion58and the another reinforcing composite layer59are a mirror image of the support portion24and the reinforcing composite layer26.

The seat back22typically includes at least one cross member60extending between the support portion24and the second support portion58for increasing the strength and stiffness of the seat back22. The cross member60comprises the thermoplastic material and is integral with the support portion24and the second support portion58. Specifically, as shown inFIGS. 1-3, the seat back22is generally U-shaped with a pair of legs62spaced from each other and extending generally in parallel. The cross member60extends between and is coupled to the pair of legs62. One of the pair of legs62is defined by the support portion24and the reinforcing composite layer26and the other of the pair of legs62is defined by the second support portion58and the other reinforcing composite layer59. The reinforcing composite layer26and the other composite layer59extend along one of the pair of legs62, respectively, to reinforce the support portion24and the second support portion58, respectively. Specifically, the reinforcing composite layer26and the second reinforcing composite layer28reinforce the support portion24and the second support portion58, respectively, from buckling or cracking when subjected to loads. The reinforcing composite layer26may be located at critical areas of the seat back22to increase the impact stiffness of the seat back22.

The thermoplastic material defines seat back features integral, i.e., one-piece, with the support portion24, the second support portion58, and/or the cross member60. Specifically, as shown inFIGS. 1-3, the cross member60defines headrest guides64. The cross member60receives a headrest (not shown) in the headrest guides64. It should be appreciated that the support portion24, the second support portion58, and the cross member60may define any seat back feature known to one skilled in the art such as, but not limited to, a back panel, side bolsters, trim attachments, foam supports, back supports, armrest mounts, lumbar support, airbag mounts and/or housing, back suspension mounts, and any combination thereof. It should also be appreciated that the seat back features such as the back panel and the side bolsters may present class A surfaces, i.e., surfaces that are exposed to occupants of the vehicle. For example, in the scenario where the support portion is formed by plastic injection molding, the seat back features are also formed along with the support portion by plastic injection molding.

In one configuration, cross member composite layer61is integrated with the cross member60to reinforce the cross member60. The cross member composite layer61typically comprises the same materials such as that described herein with respect to the reinforcing composite layer26and is typically formed in a manner such as that described herein with respect to the reinforcing composite layer26. The cross member composite layer61is also typically integrated with the cross member60in a manner such as that described herein with respect to the integration of the support portion24and the reinforcing composite layer26. It should be appreciated that the seat back22may include any number of reinforcing composite layers26and each reinforcing composite layer26may be located anywhere along the seat back22.

The present invention further includes a method of forming the composite component20. The composite component20is formed with a mold66. Specifically, the method includes the steps of placing the reinforcing composite layer26into the mold66, heating the thermoplastic material to a molten state, and disposing the thermoplastic material in the molten state into contact with the reinforcing composite layer26. The method further includes promoting interaction between the thermoplastic material of the support portion24and the polymeric material of the reinforcing composite layer26to integrate the support portion24and the reinforcing composite layer26.

Typically, the step of heating the thermoplastic material and disposing the thermoplastic material in to the mold66is further defined as injection molding with the use of the injection mold36. In such a configuration, the step of disposing the thermoplastic material into the mold66includes injecting the thermoplastic material into the injection mold36under pressure.

As shown inFIG. 7, the injection mold36includes a main cavity68and a main core70. The main cavity68and the main core70are moveable relative to each other between a closed position for plastic injection into the injection mold36and an open position for removal of the composite component20from the injection mold36. Specifically, as shown inFIG. 7, the injection mold36for the composite component20includes the main cavity68, the main core70, a first side core72, and a second side core74. In such a configuration, preferably the main cavity68remains stationary and the main core70, the first side core72, and the second side core74are moveable between the open and closed positions. Arrows A are shown inFIG. 7to illustrate the movement of the main core70, the first side core72, and the second side core74.

The method of the present invention includes the steps of moving the injection mold36to the open position, placing the reinforcing composite layer26in the injection mold36, and moving the injection mold36to the closed position. The method further includes the step of injecting the thermoplastic material into the injection mold36such that the support portion24is formed by the thermoplastic material and is integrated with the reinforcing composite layer26. Specifically, the reinforcing composite layer26presents a contact surface79and the thermoplastic material is introduced into contact with the reinforcing composite layer26along the contact surface79.

The step of promoting the interaction between the thermoplastic material of the support portion24and the polymeric material of the reinforcing composite layer26combines the thermoplastic material and the reinforcing composite layer26into a single unit. In other words, when the thermoplastic material in the molten state is introduced into contact with the reinforcing composite layer, the thermoplastic material of the support portion24and the polymeric material of the reinforcing composite layer26interact with one another such that upon cooling, the support portion24and the reinforcing composite layer26are integral with each other, i.e., one-piece.

The step of promoting interaction is further defined as melt bonding the thermoplastic of the support portion24and the polymeric material of the reinforcing composite layer26. Specifically, the method includes melting at least a portion of the polymeric material of the reinforcing composite layer26in contact with the thermoplastic material in the molten state to melt bond the composite and the thermoplastic material upon cooling. Melt bonding occurs when the thermoplastic material in the molten state interacts with the polymer of the reinforcing composite layer26while the polymeric material is in a heated softened state or a molten state. The thermoplastic material and the polymeric material interact with one another such that upon cooling the thermoplastic material and the polymeric material are bonded together. Specifically, heat may be transferred from the thermoplastic material in molten state to the polymeric material. The heat softens or melts the polymeric material and the softened or melted polymeric material interacts with the thermoplastic material in the molten state.

In the configuration where the first melting temperature of the thermoplastic material is greater than the second melting temperature of the polymeric material, the step of melting the polymeric material is further defined as disposing the thermoplastic material at the first melting temperature into contact with the reinforcing composite layer26such that the second melting temperature is realized during contact. When the thermoplastic material at the first melting temperature is introduced into contact with the reinforcing composite layer26, heat is transferred from the thermoplastic material to the polymeric material such that the temperature of the polymeric material is increased to the first melting temperature, thereby melting the polymeric material.

The step of melting the polymeric material is further defined as disposing the thermal mass56of thermoplastic material in the molten state into contact with the composite layer to transfer heat from the thermal mass56to the polymeric material. The thermal mass56is best shown inFIG. 8B. The thermal mass56heats the reinforcing composite layer26at the interface of the reinforcing composite layer26and the thermoplastic to melt the polymeric material of the reinforcing composite layer26. The thermal mass56is thicker than the rib25to provide a larger contact area with the thermoplastic material and holds more heat energy than the rib25alone.

In addition to heat transfer from the thermoplastic material, the melting of the polymeric material of the reinforcing composite layer26may be promoted in a variety of ways. For example, the step of melting the polymeric material is further defined as heating the mold66to conductively heat the reinforcing composite layer26. The reinforcing composite layer26is heated such that less heat energy is required from thermoplastic material in the molten state to raise the polymeric material to the second melting temperature.

Alternatively, or in addition, the method may include heating the reinforcing composite layer26prior to disposing the thermoplastic material in the molten state into contact with the reinforcing composite layer26. For example, the method may include heating the reinforcing composite layer26prior to placing the reinforcing composite layer26into the mold66. Alternatively or in addition, the method may include the step of heating the reinforcing composite layer26while the reinforcing composite layer26is disposed in the mold66.

For example, the method may include the step of insulating the mold66near the interface of the thermoplastic material and the reinforcing composite layer26. Specifically, in the configuration where introduction of the thermoplastic material into the mold66is further defined as plastic injection molding, the process of plastic injection molding heats the injection mold36and the step of insulating the injection mold36maintains heat in the injection mold36. The heat of the injection mold36softens the polymeric material of the reinforcing composite layer26to foster melt bonding between the thermoplastic material and the polymeric material when the thermoplastic material is injected into the injection mold36.

The method may include the step of heating the mold66near the interface of the thermoplastic material and the reinforcing composite layer26. For example, the mold66may include heated oil lines carrying heated oil. Heat is transmitted from the oil to the mold66to heat the mold66. The heat transferred to the mold66by the oil lines softens the polymeric material to foster melt bonding between the thermoplastic material and the polymeric material when the thermoplastic material is introduced into contact with the polymeric material.

The method may include the step of blowing heated air on the reinforcing composite layer26to heat the reinforcing composite layer26. For example, the mold66may include an air pocket and heated air is blown from the air pocket onto the reinforcing composite layer26when the reinforcing composite layer26is disposed in the mold66. The heated air may be directed to blow on the reinforcing composite layer26at the interface of the thermoplastic material and the reinforcing composite layer26prior to introduction of the thermoplastic material to the interface. The heated air softens the polymeric material of the reinforcing composite layer26to foster melt bonding between the thermoplastic material and the reinforcing composite layer26when the thermoplastic material is introduced into contact with the reinforcing composite layer26.

The method may include the step of plasma treating or flame treating the reinforcing composite layer26to relieve surface tension of the reinforcing composite layer26. The plasma treatment or flame treatment is applied to the reinforcing composite layer26at the interface of the thermoplastic material and the reinforcing composite layer26prior to introduction of the thermoplastic material to the interface. The plasma treatment or flame treatment of the reinforcing composite layer26reduces surface tension and which promotes melt bonding between the thermoplastic material and the reinforcing composite layer26.

The method may include the step of contacting the reinforcing composite layer26with plasma treat inserts to heat the reinforcing composite layer26. The plasma treat inserts are contacted with the reinforcing composite layer26at the interface of the thermoplastic material and the reinforcing composite layer26prior to introduction of the thermoplastic material to the interface. The plasma treat inserts are removed from the reinforcing composite layer26prior to the introduction of the thermoplastic material to the interface. The plasma treat inserts soften the reinforcing composite layer26to foster melt bonding between the thermoplastic material and the reinforcing composite layer26when the thermoplastic material is introduced into contact with the reinforcing composite layer26.

Alternatively, the step of promoting interaction is further defined as mechanically interlocking the support portion24and the reinforcing composite layer26. Specifically, the step is further defined as introducing the thermoplastic material in the molten state through the hole38to define the plug40extending through and engaging the reinforcing composite layer26through the hole38upon cooling of the thermoplastic material. Upon cooling, the thermoplastic material is mechanically interlocked with the reinforcing composite layer26.

Alternatively, or in addition to melt bonding and mechanical interlocking, the step of promoting interaction is further defined as scarifying the contact surface79prior to disposing the thermoplastic material in the molten state into contact with the reinforcing composite layer26. In other words, the contact surface79is roughened to promote melting of the reinforcing composite layer26at the contact surface.

The step of promoting interaction is further defined as applying an adhesion promoter onto the reinforcing composite layer26prior to disposing the thermoplastic material in the molten state into contact with the reinforcing composite layer26. For example, the adhesion promoter is applied to the reinforcing composite layer26by spraying, brushing, and/or bathing. The adhesion promoter promotes the melt bonding between the thermoplastic material of the support portion24and the polymeric material of the reinforcing composite layer26. An example of such an adhesion promoter is Gamma-aminopropyl triethoxysilane such as that commercially available from Dow Corning located in Midland, Mich. under the tradename Z-6011 Silane. Another example of such an adhesion promoter is Methylendiphenylbishexahydroazepincarboxamid such as that commercially available from EMS-Primid located in Sumter, S.C. under the tradename Grilbond IL-6.

The method also typically includes the step of preforming the reinforcing composite layer26into a predetermined shape prior to placing the reinforcing composite layer26into the mold66. The step of preforming is further defined as thermoforming. Alternatively, the step of preforming is further defined as compression molding. In the configuration including the plurality of reinforcing composite layers42, the plurality of reinforcing composite layers42are combined as the single stack48by compression thermoforming or compression molding. It should also be appreciated that the mold66is configured such that the reinforcing composite layer26is bent or deformed when placed in the mold66. In such a configuration, the reinforcing composite layer26maintains such a bend or deformation after the thermoplastic material is integrated with the reinforcing composite layer26.

The reinforcing composite layer26is typically preformed with the use of a preforming mold76. The preforming mold76includes a female preforming mold half78having a preforming cavity80corresponding to the predetermined shape and a male preforming mold half82corresponding to the preforming cavity80. In the configuration where the reinforcing composite layer26is preformed by thermoforming, reinforcing composite layer26is heated and placed in the preforming cavity80whereby the male preforming mold half82exerts force on the reinforcing composite layer26to permanently deform the reinforcing composite layer26in the preforming cavity80. In the configuration where the reinforcing composite layer26is preformed by compression molding, the reinforcing composite layer26is placed in the preforming cavity80and the male preforming mold half82exerts force on the reinforcing composite layer26to permanently deform the reinforcing composite layer26in the preforming cavity80.

The predetermined shape is determined based on the structural reinforcement that the reinforcing composite layer26is to provide to the composite component20. In the configuration where the thermoplastic is injection molded, the predetermined shape corresponds to the shape of the main cavity68or the shape of the main core70. The reinforcing composite layer26is typically positioned flush with the main cavity68or the main core70when the reinforcing composite layer26is disposed in the injection mold36. In such a configuration, the thermoplastic material contacts one side54of the reinforcing composite layer26such that the reinforcing composite layer26partially forms an exterior of the composite component20. Specifically, with the seat back22, the reinforcing composite layer26is shaped to correspond to the shape of one of the legs62. It should be appreciated that the reinforcing composite layer26may also be positioned in the injection mold36such that the plastic encapsulates the reinforcing composite layer26.

The method further includes the step of combining the plurality of composite layers42into the single stack48. The step of combining the plurality of composite layers42includes positioning at least one of the plurality of reinforcing composite layers with the continuous fibers30extending in the first direction D and positioning at least another of the plurality of reinforcing composite layers42with the continuous fibers30extending angularly relative the first direction D.