Patent Description:
Current industry practice is to use a machine known as a Hot Vacuum Applicator (HVA) machine in which the part to which a laminate is to be applied is supported, the laminate is lowered onto the part from above, and a flexible membrane is positioned over the laminate to form an air tight seal. A vacuum is then drawn, forming the flexible membrane and laminate onto the part while heat is applied. A typical HVA machine is set to dwell or bake the membrane, laminate, and part together as a stack until a critical activation temperature is reached at all regions of the laminate in contact with the part to melt and adhere the adhesive to the part, thus bonding the laminate to the surface of the part.

United States patent application <CIT> discloses a process and apparatus for veneering a thin layer on a support panel by means of an upper plate and lower plate. The upper plate supports a support frame for an elastic rubber sheet stretched perimetrically by a stretching system to form an airtight upper chamber. The upper chamber and lower chamber are connected with vacuum and pressure means that co-operate with respective inlets/outlets between the plates to shape under pressure the rubber sheet to the contour of the panel and effect the gluing of veneer thereto.

United States patent application <CIT> discloses an apparatus and process for coating three-dimensional solids, particularly doors, with plastic. A clamping frame is used to clamp a sheet of plastic, which is then coated onto the solid by a pressure cushion. The apparatus and process allow the plastic to conform to the solid without folds, even at the corners.

A typical bank of infrared (IR) heaters including lamps uniformly spaced in an array is best suited for uniformly heating generally planar structures. Parts that are highly contoured, for example having convex and/or concave surface features, may be non-uniformly heated or may reach uniform temperatures only through lengthy baking procedures using slowly rising temperatures. Such practices are energy inefficient and require considerable processing time per part.

Accordingly, a method, preferably a HVA method, is needed in which parts of all shapes, including those with complex or highly contoured surfaces, can be laminated with time and energy efficiencies.

To achieve the foregoing and other advantages, the present invention provides a method of laminating a contoured part according to claim <NUM>.

In some embodiments, the laminate is conformed to a surface of the contoured part by applying a vacuum between the flexible membrane and the contoured part.

In some embodiments, the laminate includes a first side for facing the contoured part, a second side for facing the flexible membrane, and a heat activated adhesive applied on the first side.

In some embodiments, heating the conformed laminate and contoured part includes heating the heat activated adhesive at least to an activation temperature at which the heat activated adhesive melts.

In some embodiments, heating the flexible membrane includes heating the flexible membrane to a predetermined temperature greater than the activation temperature.

In some embodiments, the predetermined temperature is at least fifty degrees Celsius greater than the activation temperature.

In some embodiments, the predetermined temperature is at least eighty degrees Celsius greater than the activation temperature.

In some embodiments, the predetermined temperature is at least one hundred degrees Celsius greater than the activation temperature.

In some embodiments, before heating the heat activated adhesive at least to the activation temperature, the laminate is conformed to the surface of the contoured part until the heat activated adhesive cools to a setting temperature that is below the activation temperature.

In some embodiments, the activation temperature is at least one hundred degrees Celsius, and, the setting temperature is below fifty degrees Celsius.

In some embodiments, positioning the heated flexible membrane into thermal contact with the contoured part includes applying a vacuum between the flexible membrane and the contoured part.

In some embodiments, maintaining the heated flexible membrane in thermal contact with the contoured part includes maintaining the vacuum.

In some embodiments, heating the flexible membrane and heating the conformed laminate and contoured part include heating with a common heat source.

In some embodiments, positioning the heated flexible membrane into thermal contact with the contoured part includes conforming the heated flexible membrane to the surface of the contoured part.

In some embodiments, conforming the heated flexible membrane to the surface of the contoured part includes applying a vacuum between the flexible membrane and the contoured part.

Embodiments of the present invention may include one or more or any combination, within the scope of the invention as defined in the claims, of the above aspects, features and configurations.

The present invention may be better understood when consideration is given to the following detailed description thereof. Such description makes reference to the included drawings, which are not necessarily to scale, and in which some features may be exaggerated, and some features may be omitted or may be represented schematically in the interest of clarity. Like reference numbers in the drawings may represent and refer to the same or similar element, feature, or function. In the drawings:.

The description set forth below in connection with the appended drawings is intended to be a description of various, illustrative embodiments of the present invention. Specific features and functionalities are described in connection with each illustrative embodiment; however, it will be apparent to those skilled in the art that the disclosed embodiments comprise at least all features of claim <NUM> and may further be practiced without each of those other specific features and functionalities. The features and functions described below in connection with one embodiment are intended to be applicable to the other embodiments described below except where expressly stated or where a feature or function is incompatible with an embodiment.

These descriptions, of which the drawings are a part, detail a method of applying a laminate to a part in a Hot Vacuum Applicator (HVA) process or method. The inventive method or process utilizes a flexible membrane to apply a laminate to the part in an HVA process. Preceding the laminate/adhesive application, the part is preheated by the heated flexible membrane thru close conformed contact, such as with the application of a vacuum, such that the part is heated (i.e., preheated) prior to the introduction of the laminate/adhesive between the flexible membrane and part. An advantage of preheating the part to be laminated is that heat transfer from the preheated part nearly instantaneously brings the adhesive on the laminate up to its activation temperature, in contrast to existing conventional methods in which a cool part has a chilling effect on the laminate/adhesive. This inventive benefit advantageously saves considerable time and energy in laminating a part, and particularly a contoured part, relative to existing conventional lamination methods in which a membrane, laminate, and cool part are stacked, a vacuum formed, and the stack heated to a process temperature required for lamination bonding without preheating the part.

The inventive method or process particularly benefits, for example, the lamination of highly contoured parts, where previous methods required considerable dwell or bake time of the stack in order to bring all portions of the laminate and part to a required activation temperature, at which the laminate adhesive melts bonding the laminate and part. To prepare the flexible membrane to preheat the part, prior to the introduction of the laminate, the membrane is superheated to a temperature above the activation temperature of the adhesive, thus imparting into the membrane sufficient thermal energy to transfer heat to the part by conduction. By the inventive use of a heated HVA flexible membrane to both preheat the part by close conformed contact and heat conduction, and subsequently conform the laminate to the preheated part, a minimum necessary delivery of heat energy into the part is achieved along the contoured surface of the part saving both time and energy. The process time for laminating a part, and the energy consumed, can each be significantly reduced while the bond strength between the laminate and the part can meet or that of prior standards or be improved.

<FIG> sequentially illustrate steps in laminating a contoured part according to the inventive method or process. A non-limiting example of a part is represented for a consistent example throughout the drawings to foster an understanding of the inventive process or method. The part represents many types of components and structures on which a laminate is to be applied for decorative, colorizing, texturizing, protective, or strengthening purposes. <FIG>, for example, particularly shows the part <NUM> mounted on a supporting fixture prior to the application of a laminate. <FIG> shows the part <NUM> dismounted from the supporting fixture and with a laminate <NUM> applied. By illustration of this example part in these and the other drawings, no limitation is made upon the inventive process or method.

The part <NUM> is chosen in the example of the drawings for having a contoured, generally non-planar geometry, with surface features that are inward recessed or concave, and surface features that are outward protruding or convex. A part to which a lamination is applied by the inventive method or process can be planar or non-planar and may have areas of each. The inventive method or process is particularly useful for applying laminates to non-planar and planar panels for example, which may be interior aircraft cabin components for use as walls, dividers, partitions and other large to small area parts.

<FIG> particularly shows a flexible membrane <NUM> being heated for use in laminating the part <NUM>. The flexible membrane <NUM> is generally fluid impermeable. The membrane <NUM> can be constructed of or with silicon. When deformation forces are applied, the flexible membrane <NUM> can closely conform to the outer surface of arbitrarily contoured parts, for example as shown in <FIG>, by mechanical stretching, and/or vacuum. The flexible membrane is resilient, returning to its neutral generally planar or sheet form as represented in <FIG> and <FIG> when deformation forces as removed. The membrane is preferably durable and able to undergo many transitions from neutral, to conformed, and back to neutral many times without replacement.

A row of arrows, referenced as heating <NUM>, is directed toward the membrane <NUM> in <FIG> to represent heating elements, heat flux, or radiant heat energy. The heating <NUM> of the flexible membrane <NUM> can be conducted using an HVA machine <NUM> as represented in <FIG>, in which a bank of infrared (IR) lamps serving as heaters <NUM> are uniformly spaced in a planar array. The periphery of the flexible membrane <NUM> in that example is attached to a hood <NUM> that carries the heaters <NUM>. The machine <NUM> raises (<FIG>) and lowers (<FIG>) the hood <NUM> relative to a table <NUM> on which the part <NUM> to be laminated is supported by a supporting fixture <NUM>. The hood <NUM> and table <NUM> form an approximate peripheral seal as the hood is lowered. The machine <NUM> includes pumping or vacuum equipment <NUM> that evacuates air <NUM> between the membrane <NUM> and part <NUM>, thus applying a vacuum and conforming the membrane <NUM> to the part <NUM> in close conformed contact as shown in <FIG>. As the air <NUM> is evacuated, a pressure differential drop develops from ambient conditions outside or above the membrane <NUM> to the evacuated interior space between the membrane <NUM> and part <NUM>, thus stretching and closely conforming the flexible membrane <NUM> to the part <NUM>.

The flexible membrane <NUM>, the part <NUM>, and the heating <NUM> are described and illustrated without further detailing the HVA machine <NUM> and without necessitating its use in the described inventive method or process. Returning to <FIG>, and in terms generic as to whether the particularly illustrated HVA machine is used, <FIG> particularly shows the heating <NUM> of the flexible membrane <NUM> for use in laminating the part <NUM>. In order to impart sufficient thermal energy into the membrane <NUM> to sufficiently preheat the part <NUM>, the membrane <NUM> is superheated to a temperature above the activation temperature of the adhesive of a selected laminate. For example, the membrane <NUM> in some examples is heated to at least fifty degrees Celsius (<NUM>) above the activation temperature, preferably at least eighty degrees Celsius (<NUM>) above the activation temperature, more preferably at least one hundred degrees Celsius (<NUM>) above the activation temperature, and even more preferably at least one hundred and twenty degrees Celsius (<NUM>) above the activation temperature. In a particular example, in which the activation temperature of the selected laminate is one hundred and three degrees Celsius (<NUM>), the membrane <NUM> is heated to at least one hundred degrees Celsius (<NUM>) above the activation temperature to a preheated temperature of at least two hundred and three degrees Celsius (<NUM>). As selected membranes may vary in differing implementations of the inventive method or process, and as selected laminates and adhesives may vary, not all implementations will follow this particular example.

In differing implementations, the material, density, and thermal properties such as heat capacity and thermal conductance of the membrane <NUM>, laminate, and part <NUM> may differ. Thus, specific temperatures and dwell times can be determined in establishing any particular implementation in view of these descriptions.

<FIG> returns to the example in which an HVA machine is used to heat the membrane <NUM> and shows the heated membrane <NUM> positioned above the supported contoured part <NUM>, which is to be laminated, in preparation for preheating the part <NUM>. In <FIG>, the heated flexible membrane <NUM> is positioned into thermal contact with the contoured part <NUM>, for example, by lowering of the hood <NUM> and evacuation of the air <NUM> previously between the membrane <NUM> and part <NUM>, thus conforming the heated membrane <NUM> to the part <NUM> in close conformed contact.

<FIG> is an enlarged view of a portion <NUM>, referenced in <FIG>, of the heated membrane <NUM> and the contoured part <NUM>. <FIG> illustrates the heated flexible membrane <NUM> conforming to the part <NUM> in thermal contact. Thermal energy is transferred by conductance from the heated flexible membrane <NUM> to the contoured part <NUM> as represented by heat flow <NUM>. The flexible membrane <NUM> is maintained in thermal contact with the contoured part <NUM> as shown in <FIG> for a dwell time to raise the surface temperature of the contoured part <NUM>. For a thin part <NUM>, a consistent temperature may be reached throughout. For thicker parts, a skin or surface depth may be particularly heated while deeper substrate portions further from the surface may be less heated or unaffected. As represented in <FIG>, heating <NUM> of the flexible membrane <NUM>, for example by the heaters <NUM> of the HVA machine <NUM>, may continue as the flexible membrane <NUM> is maintained in thermal contact with the contoured part <NUM>.

<FIG> shows the membrane <NUM> moved out of thermal contact with the contoured part <NUM>. At this stage, the contoured part <NUM> is preheated and ready for laminate application. Subsequently, in <FIG>, a laminate <NUM> is positioned between the flexible membrane <NUM> and the preheated contoured part <NUM>. The laminate <NUM>, having a first side <NUM> on which a heat activated adhesive <NUM> is applied, and a second side <NUM> opposite the first side, is oriented with the first side <NUM> and adhesive <NUM> facing the preheated contoured part <NUM>. Accordingly, the second side <NUM> faces the flexible membrane <NUM>. The laminate <NUM> is then conformed to the surface <NUM> of the contoured part <NUM> into close conformed and thermal contact with the contoured part <NUM> as shown in <FIG>. Once the membrane <NUM> is moved out of thermal contact with the contoured part <NUM> (<FIG>) the laminate <NUM> is brought into position (<FIG>), and conformed into thermal contact (<FIG>) in a prompt manner to assure the contoured part <NUM> has not cooled greatly from its preheated condition.

Returning to the example in which the HVA machine is used, the hood <NUM> is raised to lift the flexible membrane <NUM> as in <FIG> from the preheated contoured part <NUM>, permitting the laminate <NUM> to be introduced as in <FIG>, and the hood <NUM> is lowered and air previously between the membrane <NUM> and part <NUM> is evacuated, which traps and conforms the laminate <NUM> as shown in <FIG> by pressure differential.

As represented in <FIG> and <FIG>, heating <NUM> of the stacked contoured part <NUM>, conformed laminate <NUM>, and flexible membrane <NUM> may continue as the flexible membrane <NUM> is maintained in thermal contact with the contoured part <NUM>. Heating of the conformed laminate <NUM> and contoured part <NUM> may continue or be provided, for example, by heating of the flexible membrane <NUM> by the heaters <NUM> of the HVA machine as the flexible membrane <NUM> is maintained in thermal contact with the conformed laminate <NUM>, and the conformed laminate is maintained in thermal contact with the preheated contoured part <NUM>. Thus, as illustrated, heating of the flexible membrane <NUM> and heating the conformed laminate <NUM> and preheated contoured part <NUM> may be applied by a common heat source, for example the heaters <NUM>. In other embodiments, multiple heat sources may be used, for example by the heaters <NUM> from above and a separate heat source from below.

<FIG> is an enlarged view of a portion <NUM>, referenced in <FIG>, of the conformed membrane <NUM>, conformed laminate <NUM>, and contoured part <NUM>. <FIG> shows the first side <NUM> of the laminate <NUM> in close conformed and thermal contact with the preheated contoured part <NUM>, and the second side <NUM> of the laminate in close conformed and thermal contact with the flexible membrane <NUM>. <FIG> shows that the conformed laminate <NUM> and contoured part <NUM> are heated <NUM> to adhere the conformed laminate to the surface <NUM> of the contoured part <NUM>. For example, the conformed laminate <NUM> and contoured part <NUM> are heated to heat the heat activated adhesive <NUM> (<FIG>) at least to an activation temperature at which the heat activated adhesive melts.

<FIG> particularly shows that thermal energy is transferred by conductance from the heated flexible membrane <NUM> to the laminate <NUM> as represented by heat flow <NUM>, and thermal energy is transferred by conductance from the preheated contoured part <NUM> to the laminate as represented by oppositely directed heat flow <NUM>. Thus, the laminate <NUM> is heated from two opposing sides in the inventive method or process.

In at least one example, the condition represented in <FIG> and <FIG> is maintained for a dwell time to maintain the heat activated adhesive <NUM> at or above the activation temperature to facilitate adhesion to the contoured part <NUM>. For example, a heat activated adhesive that melts can flow or deform into bonding condition with the contoured part <NUM>. The dwell time also permits time for any internal stresses in the conformed laminate <NUM> to decrease or abate by plastic deformation as the laminate assumes its new shape in close conformation with the contoured part <NUM>. In a particular example in which the activation temperature of the selected laminate is one hundred and three degrees Celsius (<NUM>), the dwell time may be approximately four minutes. Other dwell times are within the scope of these descriptions according to other selected laminates and their heat activated adhesives for example.

In at least one example, after heating the heat activated adhesive <NUM> at least to the activation temperature, the laminate <NUM> is maintained as conformed to the surface <NUM> of the contoured part <NUM> until the heat activated adhesive cools to a setting temperature that is below the activation temperature. This is represented by the condition of the laminate <NUM> conformed to the contoured part <NUM> as in <FIG> and <FIG> without the heating. In returning to the example in which the HVA machine <NUM> is used, heating <NUM> is discontinued as the stacked contoured part <NUM>, conformed laminate <NUM>, and conformed membrane <NUM> cool. The pressure differential applied by vacuum is maintained to keep the stack in the conformed configuration as cooling occurs. In a particular example, in which the activation temperature of the selected laminate is one hundred and three degrees Celsius (<NUM>), the setting temperature may be approximately forty degree Celsius (<NUM>). Other setting temperatures are within the scope of these descriptions according to other selected laminates and their heat activated adhesives for example.

After the laminate <NUM> is adhered to the contoured part <NUM>, for example by cooling of the heat activated adhesive <NUM> to or below the setting temperature, the membrane <NUM> is moved out of thermal contact with the laminate and contoured part <NUM> as shown in <FIG>. The now laminated contoured part <NUM> can then be removed from the supporting fixture <NUM> and table as shown in <FIG>. Any excess laminate material can be trimmed from the periphery and from any apertures or holes in the design of the contoured part <NUM>.

In a production environment in which multiple contoured parts are to be laminated, a next contoured part <NUM> is mounted on the same or another supporting fixture <NUM>, and the flexible membrane <NUM> is again heated, as represented in <FIG>, in preparation for preheating the next contoured part <NUM>.

<FIG> is a flow chart representing a method of laminating a contoured part. <FIG> is a flow chart representing a method of preheating a contoured part to which a laminate is to be applied. Both methods are described in the following with reference to numbered steps as shown in the respective drawings and with additional reference to <FIG>, which illustrate exemplary but non-limiting implementations by which the methods of <FIG> and <FIG> can be practiced. The methods thus described should be understood in view of these combined descriptions as a whole, in view of which modifications and variation are possible. The methods of <FIG> and <FIG> can be practiced by other implementations than those expressly illustrated in <FIG>, and the implementations taught by <FIG> and their descriptions can practice methods other than those of <FIG> and <FIG>. Furthermore, steps preceding, following, and intervening between the steps expressly shown in <FIG> and <FIG> may be added without escaping the scope of these descriptions.

<FIG>, in particular, represents a method <NUM>, according to the present invention, of laminating a contoured part. In a first expressly shown step <NUM>, a flexible membrane is heated. See <FIG>, and descriptions thereof, for particular non-limiting implementations of heating a flexible membrane according to step <NUM>.

In step <NUM>, the heated flexible membrane is positioned into thermal contact with the contoured part. In step <NUM>, the heated flexible membrane is maintained in thermal contact with the contoured part to raise a surface temperature of the contoured part. <FIG> and descriptions thereof detail a particular non-limiting implementation according to steps <NUM> and <NUM>. The flexible membrane <NUM>, the part <NUM>, and the machine <NUM> particularly illustrated in <FIG> are provided as non-limiting examples.

In step <NUM>, the flexible membrane is moved out of thermal contact with the contoured part. For example, as described with reference to <FIG>, and in the example in which the HVA machine <NUM> (<FIG>) is used, the hood <NUM> is raised to lift the flexible membrane <NUM> from the preheated contoured part <NUM>, permitting the permitting the laminate <NUM> to be introduced as in <FIG>.

In step <NUM>, a laminate is positioned between the flexible membrane and the contoured part. See, for example, the implementation illustrated and described with reference to <FIG>. Placement of the laminate <NUM> may be practiced manually or may be automated. Where the laminate and part <NUM> have particular features requiring alignment, registration marks or features may facilitate accurate placement.

In step <NUM>, the laminate is conformed to the surface of the contoured part. See, for example, the implementation illustrated and described with reference to <FIG> and <FIG>, in which, in the example in which the HVA machine <NUM> (<FIG>) is used, the hood <NUM> is lowered and air previously between the membrane <NUM> and part <NUM> is evacuated, trapping and conforming the laminate <NUM> as shown in <FIG> by pressure differential. The temperature at which the laminate may be conformed to the substrate part can be around, for example, <NUM> below the activation temperature of the adhesive. This is because the softening temperature of decorative laminate products is typically lower than the activation/melt temperature of the adhesive. The laminate conforming may therefore take place before the laminate and adhesive has reached the adhesive activation temperature.

In step <NUM> (<FIG>), the conformed laminate and contoured part are heated to adhere the conformed laminate to the surface of the contoured part. See, for example, the implementation illustrated and described with reference to <FIG> and <FIG>, in which heating <NUM> of the stacked contoured part <NUM>, conformed laminate <NUM>, and flexible membrane <NUM> is shown. In the example in which the HVA machine <NUM> is used, the heaters <NUM> heat the stacked flexible membrane <NUM>, conformed laminate <NUM>, and contoured part <NUM> from above. Other implementations may use, additionally or alternatively, other heating elements, for example applying heat from below.

<FIG> is a flow chart representing a method <NUM> of preheating a contoured part to which a laminate is to be applied. In step <NUM>, a flexible membrane is heated. In step <NUM>, the heated flexible membrane is positioned into thermal contact with the contoured part. In step <NUM>, the heated flexible membrane is maintained in thermal contact with the contoured part to raise a surface temperature of the contoured part. Thus, steps <NUM>-<NUM> of the method <NUM> correspond to the steps <NUM>-<NUM> of the method <NUM> (<FIG>), and examples of implementations are provided in <FIG>. In step <NUM>, the flexible membrane is moved out of thermal contact with the contoured part, for example, as described with reference to <FIG>. Thus, in the method <NUM>, a contoured part is preheated in preparation for applying a laminate to the part. Further steps may follow, for example, as expressly included in the method <NUM>. The method <NUM>, however, is novel and non-obvious in that contoured parts were not previously preheated by conduction by use of a heated flexible membrane. Instead, a membrane, laminate, and part were stacked and heated together from above until a critical activation temperature was reached.

Thus, the present invention that is described and illustrated herein may include: a) pre-heating and sustaining the membrane at an elevated temperature prior to commencing the laminating cycle; b) raising the temperature of the membrane to a superheated state, for example <NUM> or greater above a standard HVA processing temperatures; c) pre-heating the substrate material immediately prior to the application of the laminate by bringing the super-heated membrane into direct contact with the part and applying vacuum pressure; d) sustaining the heating of the membrane in conjunction with pressurized contact with the substrate for a short time to bring the temperature of the surface of the substrate close to standard HVA processing temperatures; and e) releasing and removing the membrane followed by application of the laminate sufficiently quickly to ensure that the substrate surface does not cool significantly and remains close to standard HVA processing temperatures as the laminate makes contact. The surface of the substrate part can thus be heated to the target process temperature by direct contact with a super-heated membrane.

The inventive method, and implementations thereof, facilitate greatly shortened process cycle times, and increase the bond strength of a laminate to the substrate material, thus reducing the risk of in-service failure of laminated parts. Greater uniformity in adhesion strength may also be achieved. Less energy is input into a substrate part using this heating technique, reducing the risk of heat deformation and increasing the rate at which the part may be cooled back to room temperature. In addition, the new method or process can be carried out in an elevated temperature environment, such as within a conventional oven at <NUM>, and contrasting this to existing conventional oven systems that need to be sustained at around <NUM>.

The speed at which the substrate surface can be brought to the required process temperature is much faster through direct contact with the super-heated membrane through other possible techniques, such as heating the part first by infra-red radiation, or by placing the part in a pre-heated (convection) oven.

Heat intensity that impinges on a surface from a point source is proportional to the inverse of the square of the distance from the source of the heat. This means that a radiating heat source (e.g. IR lamps) that is optimized for the heating of laminate material (nominally flat) is not optimized for heating a contoured part. Areas of the substrate part that are further away from the heat source heat up much more slowly than areas closer to the source. This leads to uneven surface temperature over a contoured part. Some areas may become too hot, resulting in damaged material, while other areas may be too cold, resulting in poor adhesion. Using heat transfer through contact of the part with a pre-heated membrane in lieu of irradiation of the part provides a much more even temperature across the part surface.

The time taken to cool parts at the end of a process cycle is affected by the heat energy stored within the parts. The HVA process requires the substrate to have adequate surface temperature to allow for melting of the adhesive. An elevated through-body temperature, far from the surface to which a laminate is to be applied, is not needed for the process. The technique of heating the substrate using the hot membrane allows for the required surface temperatures to be reached while minimizing overall heat transfer deep into the part. The lower heat energy in the part results in faster cooling times.

<FIG> shows a plot of laminate temperature vs. time as measured for a prior process (see the temperature plot without circles) and for the new process (see the temperature plot with circles) described above as the inventive method or process. In the prior process, the membrane, laminate, and part as a stack were heated together until a critical activation temperature was reached at all regions of the laminate in contact with the part to melt and adhere the adhesive to the part thus bonding the laminate to the surface of the part, and the stack was then cooled, but the part was not preheated prior to introduction of the laminate. In each, the laminate is ultimately brought from room temperature (approx. <NUM>) to the glue activation temperature (above or near <NUM>) and then cooled to below <NUM>. <FIG> shows the new process as completing such a cycle in approximately <NUM> minutes, while the prior process required approximately <NUM> minutes. Other tests have confirmed that processing times are reduced by the new process while the adhesion strengths of panels produced using the new process meet and exceed quality standards for adhesion of the laminate onto a substrate.

Claim 1:
A method of laminating a contoured part (<NUM>), the method comprising the step of:
heating a flexible membrane (<NUM>);
characterized by the following steps which are performed sequentially:
preheating the contoured part (<NUM>) by positioning the heated flexible membrane (<NUM>) into direct conformed thermal contact with the contoured part (<NUM>);
maintaining the heated flexible membrane (<NUM>) in direct conformed thermal contact with the contoured part (<NUM>) to raise a surface temperature of the contoured part (<NUM>);
moving the flexible membrane (<NUM>) out of direct conformed thermal contact with the contoured part (<NUM>);
positioning a laminate (<NUM>) between the heated flexible membrane (<NUM>) and the preheated contoured part (<NUM>);
conforming, using the heated flexible membrane, the laminate (<NUM>) to a surface (<NUM>) of the contoured part (<NUM>); and
heating (<NUM>) the conformed laminate (<NUM>) and contoured part (<NUM>) to adhere the conformed laminate (<NUM>) to the surface (<NUM>) of the preheated contoured part (<NUM>).