Patent Publication Number: US-6217656-B1

Title: Pan holder for coating process

Description:
FIELD OF THE INVENTION 
     This invention pertains generally to containers such as pans and other cookware articles and methods for making such articles, and, more particularly, to systems and methods for applying coatings, such as non-stick release coatings, to such articles, and for holding the articles during a coating application process. 
     BACKGROUND OF THE INVENTION 
     Articles of cookware, such as pans of various sizes, may be made of a variety of substrate materials, such as ceramic, glass, or metal materials, such as stainless steel, copper, or aluminum. Often it is desirable to apply a coating to at least the interior surface of such cookware articles. Various types of coatings may be applied, including coatings designed to protect the inside surface of the cookware from damage due to abrasion and/or corrosion, and/or to provide a non-stick release coating on the inside surface of the cookware article so that food cooked in the cookware is easily removed therefrom. 
     Although various methods, such as roller and dip coating, may be used to apply a coating to the inside surface of an article of cookware, coatings are typically applied to cookware by spraying a desired coating material onto the interior surface of the cookware. Modern cookware coatings, such as non-stick release coatings, require several coating material application and curing steps to achieve the desired surface finish. For example, a non-stick release coating may be applied to the interior surface of a metal pan by applying a primer material to the inside pan surface, drying the primer layer in a hot air environment, applying one or more intermediate and top coats of non-stick material over the primer layer, and then curing or baking the pan once again in a hot air environment. 
     Effective and efficient processes have been developed for applying coatings to articles of cookware in a mass production industrial setting. Such industrial processes involve conveying a series of articles of cookware to be coated through each step in a coating process. A typical process for applying a coating to the inside surface of an article of cookware employs a chain-on-edge spray line. A chain-on-edge spray line employs a conveyor chain to transport articles of cookware through various stages in a process whereby coating materials are applied to the cookware and where the applied coating materials are dried or cured. The conveyor chain is formed of a plurality of links. Each link has a central aperture formed therein. A plurality of pan holders are mounted spaced apart on the conveyor chain. Each pan holder includes a pan holder chuck, whereby the pan holder is mounted on the conveyor chain, and a pan holding means, attached to the chuck, for holding a pan or other article which is to be transported through the coating process stages. The pan holder chuck includes a shaft, which extends downward through the central aperture in a link in the conveyor chain, and a pulley mounted to the shaft. The pulley is adapted to be engaged by a drive belt, which rotates the shaft, and, therefore, the entire pan holder, with respect to the conveyor chain. The pan holding means is typically implemented as a cylinder or other receptacle, having an upward facing opening formed therein adapted to receive a pan or other article of cookware to be coated. A pan blank, or other article of cookware to be coated, is dropped into the opening in the pan holding means. The pan is held in place in the holding means by the weight of the pan. 
     A pan held in the pan holder is transported through the various coating process stations by the conveyor chain. At a first processing station, for example, a primer material may be applied onto the interior surface of the pan. This may be achieved by extending a spray nozzle near or into the interior of the pan, and spraying a primer material in liquid form from the nozzle onto the interior surface of the pan. To ensure a relatively even coating of material is applied on the pan surface, the pan is preferably rotated as the primer material is sprayed thereon. A drive belt is thus provided in the primer material application station. The drive belt is positioned such that the pulley on the pan holder chuck engages the drive belt as the conveyor chain transports the pan holder through the primer application station. The drive belt rotates the pan holder, and the pan attached thereto, via the pulley while the primer coating material is sprayed onto the interior surface of the pan. Following the primer application station, the pan may be conveyed by the conveyor chain through a heat curing station, and one or more intermediate and/or top coat application stations, wherein, for example, one or more coats of non-stick coating material may be applied to the interior surface of the pan. Since the pan blank need not be rotated during the curing stage, a drive belt is typically not provided in the curing station. The intermediate and top coats of material may be applied in a manner similar to the manner in which the primer coating is applied, e.g., by spraying the material onto the interior surface of the pan while the pan is rotated. Thus, drive belts are typically provided in all of the coating material application stations to engage the pulley mounted on the pan holder chuck, to thereby rotate the pan holder and the pan held therein during the coating application process. After all coating material layers have been applied, the coated pan blank or other article is removed from the pan holder for further curing and/or processing steps. 
     For most conventional cookware coatings, such as most non-stick release coatings, the coating application process just described is efficient, effective, and economical. The pan holders employed in such a process are relatively inexpensive. The pan holding means employed, however, do not hold pans transported thereby tightly in position during the coating application process. A pan blank, which is held in position in the pan holder by its own weight, will shift position during the coating application process. For many applications, however, this pan movement does not seriously adversely affect the quality of the finished product. 
     Recently, a method has been developed for producing a pattern in the non-stick release coating applied to the interior surface of an article of cookware by magnetically reorienting reflective magnetizable flakes dispersed in the non-stick coating material. Reflective flakes made of a magnetizable material, such as iron, nickel, and alloys containing these metals, such as stainless steel, are mixed in a liquid fluoropolymer non-stick coating material. The non-stick coating material, with the metal flakes mixed therein, is applied to the inside surface of an article of cookware in a conventional manner, e.g., by spraying the material onto the inner surface of the cookware. In the absence of a magnetic field, the magnetizable reflective flakes will be oriented parallel to the cookware surface, i.e., horizontally. However, if a magnetic field is applied to the cookware, either during application of the coating material to the cookware or after application of the coating material but before the coating material dries or hardens, the reflective magnetizable flakes in the magnetic field will become aligned with the magnetic field, i.e., will be reoriented vertically or perpendicular to the cookware surface. When the non-stick coating material is cured, the reoriented magnetizable reflective flakes will be fixed in this vertical position. The horizontally oriented reflective flakes will reflective light back to an observer, the vertically oriented flakes will not. Thus, a pattern, which appears three dimensional to the eye, is created in the non-stick release coating of the cookware. As long as the magnetizable reflective flakes are selected to have the proper dimensions, i.e., no longer than slightly more than the thickness of the fluoropolymer non-stick release coating, the pattern formed in the coating in this manner will not adversely affect the performance of the non-stick release coating. 
     The shape of the pattern produced in the release coating of the cookware is defined by the shape of the magnetic field applied to the cookware while the fluoropolymer release coating material containing the magnetizable flakes is applied thereto in liquid form. A magnetic field of the desired shape can be achieved by placing a die pattern, e.g., a metal plate in the shape of the desired pattern to be produced in the cookware release coating, against an outside of the cookware, with a magnet (either a permanent magnet or an electromagnetic) placed against the die pattern. The magnet and die pattern in combination produce a magnetic field in the shape of the die pattern on the inside surface of the cookware while the fluoropolymer release coating material containing the magnetizable reflective flakes is applied to the interior surface of the cookware, or after the coating is applied, but before the coating solidifies to thereby reorient a portion of the metal flakes in the coating material in the shape of the die pattern. Such a process is described, for example, in Great Britain Patent No. 1,131,038. This process can, however, produce a “fuzzy” pattern, i.e., a pattern which lacks clarity, in the cookware release coating. When a shaped die pattern is laid directly across the top of the magnet, the resultant imprint of the die pattern formed in the release coating is especially fuzzy where the magnetic force of the magnet is directed through the bulk area of the die pattern. The fuzzy image is a manifestation of unwanted field lines (magnetic background effects). If a stronger magnet is used to try to eliminate the fuzziness of the image, i.e., sharpen the image, another unwanted background effect occurs, namely reproduction of the shape of the magnet itself in the pattern formed in the coating. It has been found that a sharper image pattern may be formed in the release coating if the magnetic force applied to the magnetizable reflective flakes is from a diffused magnetic field, rather than directly from the magnet itself. This is achieved by spacing the magnet, which is the source of the magnetic force, away from the substrate being coated. Magnetic force is thus preferably communicated across the space between the magnet and the flakes in the coating from a diffuse magnetic field intervening between the magnet and the coating through the die pattern of magnetizable material positioned between the diffused magnetic field and the coating on the substrate. The diffused magnetic field isolates the coating from direct exposure to the magnetic field of the magnet, eliminating unwanted background effects from the pattern, thereby improving pattern clarity. A diffused magnetic field may be created by placing a magnetizable diffusion plate between the magnet and the die pattern and/or by spacing the magnet from the dye pattern such that the coating on the substrate is not directly exposed to the magnetic force of the magnet. Such a process is described in U.S. patent application Ser. No. 09/144,766, filed on Sep. 1, 1998 now U.S. Pat. No. 6,103,361. 
     It is desirable that conventional industrial processes for applying coating materials to cookware articles be adapted to the production of cookware articles having patterns formed in the non-stick release coatings thereof by the magnetic reorientation of reflective magnetizable flakes in the coating material, in the manner described. 
     SUMMARY OF THE INVENTION 
     The present invention provides a pan holder for holding an article of cookware in position while applying a coating material thereto. A pan holder in accordance with the present invention is especially adaptable for holding an article of cookware in position during the process of applying a non-stick release coating material to the interior thereof. In particular, a pan holder in accordance with the present invention holds an article of cookware in position in the pan holder while a non-stick release coating material is sprayed onto the interior surface of the cookware as the cookware is rotated. The pan holder of the present invention prevents movement of the article of cookware with respect to the pan holder during such rotation. A pan holder in accordance with the present invention will find particular applicability in processes for forming patterns in the non-stick release coatings of articles of cookware by the magnetic orientation of reflective magnetizable flakes in the coating materials applied thereto. For such applications, a pan holder in accordance with the present invention may include a magnetizable die pattern and a magnet for providing magnetic force to the die pattern to produce a magnetic field in the shape of the die pattern through a pan or other article of cookware being held in the pan holder during the application thereto of a release coating material having reflective magnetizable metal flakes mixed therein. The magnetic field thus applied to the article of cookware reorients a portion of the metal flakes in the shape of the die pattern. The pan holder of the present invention holds the pan or other article of cookware tightly against the die pattern during the coating material application process. Thus, fuzziness, or a lack of clarity in the pattern produced in the release coating, which might be caused by movement of the pan with respect to the die pattern during application of the coating material, is prevented. 
     A pan holder in accordance with the present invention includes a pan holding means and a pan holder chuck. The pan holding means includes a bottom support piece and at least two, but preferably three or more, pan support rods extending vertically from the bottom support piece. The bottom support piece may be plate or ring shaped, and is preferably made of a non-magnetic material, such as aluminum. The pan support rods may extend directly from the bottom support piece, or may be attached to the bottom support piece via support arms which extend radially from the bottom support piece. The pan support rods are positioned and spaced from each other on the bottom support piece so as to provide means for holding a pan or other article of cookware between them. 
     Preferably at least one of the support rods is moveable in a radial direction, and is biased inward toward the axial center of the pan holder. For example, a moveable support rod may be attached in a hinged relation to the bottom support piece, or to a support arm extending therefrom. A compression spring may be positioned against the moveable support rod to bias the rod toward the axial center of the pan holder. Thus, when a pan or other article is positioned in the pan holding means, between the pan support rods, the moveable support rod is biased against the pan to press the pan against the other support rods, thereby holding the pan in position on the pan holder. The movable support rod also ensures that a pan or other article is held in position in the pan holder despite slight inconsistencies in the diameter of a pan or other article. 
     The movable vertical support rod preferably also includes a means for engaging the handle studs typically found on a pan blank or article of cookware shell. The handle studs extend from the pan blank for attaching a handle thereto. For example, the movable vertical support rod may include two extending portions extending therefrom, with a notch formed between the extending portions. The handle stud on a pan blank or shell is positioned in the notch when the movable support rod is biased against the pan blank. The means for engaging the handle stud thus provides further support for the pan blank within the pan holder, thereby enhancing the ability of the pan holder to prevent movement of the pan blank in the holder during rotation thereof. 
     The pan holder chuck is attached to the bottom support piece of the pan holding means. The pan holder chuck includes a vertically extending chuck shaft and a pulley attached to and around the shaft. The chuck shaft is designed to extend into the central aperture of a link in a conveyor chain in a chain-on-edge spray line. The pulley is adapted to be engaged by a drive belt as the pan holder is transported by the conveyor chain through a coating material application station. The drive belt rotates the pan holder, and a pan held therein, via the pulley, while a coating material is sprayed onto the interior surface of the pan blank in the coating application station. The pulley may be attached permanently to the shaft, or may be attached thereto using a set screw or other mechanism whereby the position of the pulley on the shaft may be adjusted to accommodate various drive belt positions with respect to the conveyor chain. 
     A pan holder in accordance with the present invention may be adapted for use in an industrial process for forming a pattern in a non-stick release coating applied to a pan or other cookware article by the magnetic reorientation of reflective magnetizable flakes distributed in the coating material. Such a pan holder in accordance with the present invention includes a magnetic die pattern and a magnet attached to the pan holder holding means and chuck. The die pattern is made of a magnetizable material formed in the shape of a desired pattern to be formed in the release coating applied to the cookware article. The die pattern is positioned on the bottom support piece, between the pan support rods. When a pan blank is positioned in the pan holder holding means between the support rods, an outside surface of the pan blank is held in contact with the die pattern thereby. The magnet, which may be an electromagnet or a permanent magnet, is magnetically coupled to the die pattern. The magnet may be attached directly to the die pattern, but is preferably coupled to the die pattern through a spacer piece, which is preferably made of a magnetic material. The spacer piece defuses the magnetic field generated by the magnet as applied to the die pattern, which results in a sharper image produced in the release coating of the cookware. The spacer piece may be attached to the bottom support piece of the pan holding means, between the magnet and the die pattern. Preferably, the spacer piece is attached to a ring shaped bottom support piece in a central aperture thereof. The die pattern is attached directly to the spacer piece, such as by threading the die pattern onto a threaded insert extending vertically from the spacer piece along the axis of the pan holder. The magnet is attached to the spacer piece, and may be held in position thereon by fasteners or by the magnetic force between the magnet and the spacer piece. 
     The magnet is preferably contained in a magnet housing, which is made of a non-magnetic material, such as plastic. The magnet housing may include a recessed top surface and/or notches or other alignment means formed therein for engaging a corresponding stepped bottom notches, or other alignment means formed in the spacer piece, to provide proper alignment between the magnet housing and the spacer piece, and to prevent rotation of the magnet housing with respect to the spacer piece. The pan holder chuck, including the shaft and pulley, may be attached to the pan holder holding means via the magnet housing. Thus, the chuck may be attached to the magnet housing, such that the chuck is attached to the pan holder holding means when the magnet housing is attached to the spacer piece. 
     The spacing between the pan support rods on the pan holding means of a pan holder in accordance with the present invention defines the size of cookware article which may be held by the pan holder. Means may be provided for changing the length of the support rods, to allow the pan holder to hold a cookware article which is larger or smaller in the vertical direction, or for allowing the pan support rods to be moved in a radial direction, to allow the pan holder to hold an article of cookware having a larger or smaller radius. Alternatively, the pan support rods may be mounted at a fixed height and/or in a fixed position on the pan holder. In such a case, different pan holder holding means, having support rods mounted thereon with different spacings between rods, will be required for holding differently sized pans. Preferably, the magnet housing, including the magnet therein, and having the pan holder chuck, including the chuck shaft and pulley, attached thereto, may be provided as a magnet/chuck assembly which is easily detachable from and attachable to the pan holding means of a pan holder in accordance with the present invention. Such a magnet/chuck assembly may be used in combination with pan holder holding means having pan support rods with various spacings therebetween attached thereto. Thus, a single magnet/chuck assembly in accordance with the present invention may be employed with pan holder holding means which are adapted for use with various sized articles of cookware. Since the magnet and chuck components form a significant portion of the cost of a pan holder in accordance with the present invention, significant cost savings can be had if a single magnet/chuck assembly in accordance with the present invention is adapted for use with pan holding means adapted to hold differently sized pans. 
     In operation, a plurality of pan holders in accordance with the present invention are mounted spaced apart on a conveyor chain for transporting pans or other articles of cookware through various stations at which the various steps of a coating process are performed. For example, pan holders in accordance with the present invention may be placed approximately 18″ apart in apertures formed in the links of a conveyor chain in a chain-on-edge spray line. Each pan holder is mounted on the conveyor chain by extending the pan holder chuck shaft through a link in the chain. A pan blank or other cookware shell is positioned in each pan holder holding means between the pan support rods thereof. At least one of the support rods preferably is a movable support rod which is biased radially against the pan blank, to hold the pan blank in place in the pan holding means. A handle stud formed on the pan blank may be positioned in a handle stud engaging means formed on the movable pan support rod, to provide additional support against movement of the pan blank. The pan blank may be held in place against a magnetic die pattern, which may be attached to the pan holder by the support rods. A magnet and spacer piece may be coupled to the die pattern, thereby generating a diffuse magnetic field through the article of cookware in the shape of the die pattern. 
     A pan holder in accordance with the present invention may be employed in various processes for applying coatings to the surfaces of containers, such as articles of cookware. A pan holder in accordance with the present invention will be found particularly useful in processes for applying a non-stick release coating to an article of cookware wherein reflective magnetizable flakes in the coating material are re-oriented in a pattern to form a visible pattern in the release coating. Such a process may involve several processing steps, performed at a series of processing stations. A pan blank, or other article of cookware, which is to have such a patterned release coating formed thereon, is transported through the various processing stations using a pan holder in accordance with the present invention. The pan holder of the present invention holds the pan blank in position against a magnetizable die pattern during the various steps of the coating application process. Such steps may include, for example, the application of a primer coating material to the uncoated pan blank, drying of the primer coating, the application of an intermediate coat of release material, having reflective magnetizable flakes suspended therein, over the primer layer, and the application of a top coat of release coating material over the intermediate coat. The primer, intermediate, and top coats are preferably applied by spraying the coating materials onto the surface, e.g., the interior surface, of the pan blank as the pan blank is rotated. The pan holder in accordance with the present invention holds the pan blank in position in the pan holder during such rotation. Holding the pan blank in position against the magnetized die pattern during the application of a coating material, containing the reflective magnetizable flakes therein, ensures that a minimum number of flakes outside of the magnetic field applied via the pattern are re-oriented, thereby resulting in a clear pattern image formed by the flakes in the release coating. 
     Further objects, features, and advantages of the present invention will be apparent from the following detailed description taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a plan view of an exemplary pan holder in accordance with the present invention, having a star shaped magnetizable die pattern attached thereto. 
     FIG. 2 is a side view, in partial cross-section, of the pan holder of FIG. 1, showing a pan or other article of cookware held thereon, and wherein a magnet/chuck assembly is shown separated from the other portions of the pan holder. 
     FIG. 3 is a schematic illustration of a chain-on-edge spray line for applying a non-stick release coating to the inside surface of a pan or other article of cookware, illustrating an exemplary application of a pan holder in accordance with the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention provides a pan holder for holding a container such as a pan or other article of cookware during the process of applying a coating material thereto. The present invention will be described in detail herein with respect to the exemplary application of a process for applying a non-stick release coating to the interior surface of a pan blank. It should be understood, however, that the present invention is not limited to processes for the application of coatings to cookware, but may find application in processes for applying coatings to a variety of other containers and articles. In addition, it should be understood that a pan holder in accordance with the present invention is not limited to use in processes for the application of a non-stick release coating to the inside surface of a container, but may be applied in processes for applying various other types of coatings to other surfaces of such containers or articles. 
     An exemplary pan holder  10  in accordance with the present invention is illustrated in, and will be described in detail with reference to, FIGS. 1 and 2. The two main components of a pan holder  10  in accordance with the present invention are a pan holding means  12  and a chuck  14  attached to the pan holding means  12 . The pan holding means includes a bottom support piece  16 , and a plurality of pan support rods  18  extending vertically from and attached to the bottom support piece  16 . The bottom support piece  16  may be formed as a round circular or ring-shaped plate, and is preferably made of a non-magnetic material, such as aluminum. It should be understood that the bottom support piece  16  may have a different shape than that illustrated by example in FIGS. 1 and 2, and may be made of other appropriate materials. 
     The support rods  18  may be attached directly to the bottom support piece  16  in a conventional manner. Alternatively, as illustrated in FIGS. 1 and 2, the support rods  18  may be attached to the bottom support piece  16  via support arms  20  which are attached to and extend radially from the bottom support piece  16 . The radially extending support arms  20  may be attached to a bottom surface of the bottom support piece  16  (as illustrated in FIGS.  1  and  2 ), to a top surface of the bottom support piece  16 , or to the radial edge of the bottom support piece  16 . The radially extending support arms  20  may be attached securely to the bottom support piece in a conventional manner, e.g., using conventional fasteners  22 , such as bolts or screws, or may be integrally formed as part of the bottom support piece  16 . 
     The pan support rods  18  may be attached to the support arms  20  (or directly to the bottom support piece  16 ) in a conventional manner. For example, the pan support rods  18  may be formed as threaded rods, made out of stainless steel or another appropriate material, adapted to be threaded into threaded holes formed in the support arms  20  (or bottom support piece  16 ). The support rods  18  preferably extend vertically, or approximately vertically, i.e., at approximately a right angle, from the bottom support piece  16 . The pan support rods  18  are preferably spaced apart from each other at equal distances from each other along the circumference of an imaginary circle, centered on an axis of the pan holder  10 . Thus, the pan support rods  18  are positioned with respect to each other so as to support a round pan blank  24 , or other article of cookware, positioned in the pan holding means  12  between the support rods  18 . Of course, the pan support rods  18  may be positioned in a different configuration with respect to each other for holding a differently shaped article in the pan holder  10 . 
     Each vertical support rod  18  preferably has a cap  26  or other structure attached to the distal end thereof and made of a relatively compliant material, such as silicone or a compliant plastic material. The support rod caps  26  are preferably made of a material selected to provide a high degree of friction between the cap  26  and the pan blank  24  held in the pan holder  10 , to provide a better grip by the support rods  18  on the pan blank  24 , while preventing scratching or other abrasion of the wall of the pan blank  24  where the pan blank  24  and the support rods  18  come in contact. 
     Preferably at least three pan support rods  18  are provided on the pan holding means  12 . Preferably at least one of the support rods  18  is a moveable support rod  18 A. The moveable support rod  18 A is biased inwardly in a radial direction such that when a pan blank  24  is positioned in the pan holding means  12 , between the movable support rod  18 A and the other support rods  18 , the movable support rod  18 A presses the pan blank  24  against the other support rods  18 , thereby to hold the pan blank  24  firmly in position in the pan holding means  12 . 
     Various mechanisms may be employed for biasing the movable support rod  18 A inwardly in a radial direction. For example, the movable support rod  18 A may be attached in a hinged relation to a radially extending support arm  20  with a compression spring mechanism mounted on the support arm  20  to bias the movable support rod  18 A inward in a radial direction about the hinge. For exemplary purposes only, the movable support rod  18 A may be attached to a yoke shaped movable support rod holder  28 , e.g., by threading the movable support rod  18 A into a threaded aperture formed in the top  29  of the movable support rod holder  28 . The movable support rod holder  28  is positioned over the radially extending support arm  20  such that a hole  30  formed in the support rod holder  28  is aligned with a corresponding hole formed through the radially extending support arm  20 . A pin  32  (see FIG.  1 ), such as a cotterless clevis pin, is extended through the aligned holes  30  to thereby attach the movable support rod  18 A via the movable support rod holder  28  in a hinged relation to the radially extending support arm  20 . This mechanism provides the distal end of the movable support rod  18 A with a limited degree of radial movement. The movable support rod  18 A may be biased inward in a radial direction by a compression spring  34  mounted on the radially extending support arm  20 . A conventional compression spring (e.g., Lee Spring part no. LC-095J-2M) may be employed. The compression spring  34  is compressed between two washers, a fixed washer  36  positioned at the distal end of the support arm  20 , and held in place thereon in a conventional manner, such as by a bolt, screw, or other fastener  38  attached to the distal end of the support arm  20 , and a movable washer  40 . (The moveable washer  40  may preferably include a cylindrical extension portion  41  extending axially therefrom and positioned around the support arm  20  between the support arm  20  and the inside surface of the compression spring  34 , to minimize other than axial movement of the washer  40 .) The movable washer  40  is biased by the compression spring  34  against the movable support rod holder  28 . The movable washer  40  thus transfers the spring loaded tension provided by the compression spring  34  to the movable support rod holder  28 . If the support rod  18 A is rotated about the support arm  20 , such that the movable support rod  18 A moves outwardly in a radial direction, the compression spring  34  will bias the movable support rod  18 A back to a near vertical position, i.e., radially inward. Thus, the compression spring  34  acts to bias the movable support rod  18 A in an inward radial direction, to thereby hold a pan blank  24  in position between the movable support rod  18 A and the other support rods  18 . 
     A pan blank  24  or other article of cookware to be held in a pan holder  10  in accordance with the present invention may have one or more handle studs  42  formed on and extending from an outer wall thereof. The handle studs  42  may be formed as an integral part of the pan blank  24 , and are used to attach a handle to the blank  24  to form a complete pan or other article of cookware after a surface coating has been applied thereto and other processing of the pan blank  24  has been completed. Preferably, one of the pan support rods  18  in a pan holder  10  in accordance with the present invention includes a handle stud engaging means attached thereto for engaging the handle studs  42  extending from the pan blank  24 . The pan handle stud engaging means is preferably attached to the distal end of the moveable support rod  18 A. For example, as illustrated in FIGS. 1 and 2, a pan handle stud engaging means  44  may be attached to the distal end of the movable support rod  18 A, e.g., by threading the pan handle stud engaging means  44  onto the distal end of the threaded movable support rod  18 A. The pan handle stud engaging means  44  is preferably made of a semi-rigid material such as Nylatron, or a similar plastic material, which will provide a degree of friction between a surface of the pan handle stud engaging means  44  and the outer surface of the pan blank  24  without scratching or otherwise damaging the outer surface of the pan blank  24 . The pan handle stud engaging means  44  preferably includes two extending portions  45  defining a notch  46  therebetween. The width of the notch  46  is preferably only slightly larger than the width of the pan handle studs  42  extending from the outer surface of the pan blank  24 . Thus, when the pan blank  24  is positioned in the pan holding means  12  between the support rods  18  such that the pan handle studs  42  are positioned in the notch  46  formed in the pan handle stud engaging means  44 , rotational movement of the pan blank  24  in the pan holder  10  is prevented. Thus, the pan handle stud engaging means  44  provides additional support against movement of a pan blank  24  held in position in the pan holder  10  of the present invention. 
     The two main components of the pan holder chuck  14  are a chuck shaft  46  and a pulley  48 . The chuck shaft  46  extends vertically downward from the pan holding means  12 . The chuck shaft  46  is designed to ride in the central aperture of a link in a conveyor chain in a chain-on-edge spray line. The pan holder  10  is mounted on the conveyor chain by extending the shaft  46  through the central aperture of a link in the chain, and is rotated with respect to the chain about the shaft  46 . The shaft  46  may preferably be tapered slightly, as illustrated in FIG.  2 . 
     The pulley  48  is mounted around the shaft  46 . The pulley  48  may be attached to the shaft  46  in a conventional manner, or may be integrally formed as part of the shaft  46 . The pulley  48  may be attached in a fixed position on the shaft  46 , or may be attached to the shaft  46  in a manner such that the position of the pulley  48  on the shaft  46  may be adjusted. For example, the pulley  48  may be attached to the shaft  46  using a set screw (not shown), which may be loosened to adjust the position of the pulley  48  on the shaft  46 . The pulley  48  is positioned on the shaft  46  so as to be engaged by a drive belt as the pan holder  10  is transported through a coating application station by a conveyor chain. The drive belt engages the pulley  48  to rotate the pan holder  10  about the shaft  46  during the application of a coating material to the pan blank  24 . The position of the pulley  48  on the shaft  46  is preferably made adjustable so as to adjust the position of the pulley  48  for engaging drive belts mounted at different distances from a conveyor chain. 
     The pan holder chuck  14  may be attached to the pan holding means  12  in a conventional manner. For example, the chuck shaft  46  may be attached directly to the bottom support piece  16 . 
     A pan holder  10  in accordance with the present invention is preferably adapted for use in a process for forming a pattern in a non-stick coating release layer applied to a pan or other article of cookware by the magnetic reorientation of reflective magnetizable flakes distributed in the non-stick coating material as it is applied to the pan. For such applications, a pan holder  10  in accordance with the present invention preferably includes a magnetizable die pattern  50  and a magnet  52  for applying magnetic force to the die pattern  50 . 
     The die pattern  50  is made out of a magnetizable material, such as stainless steel. The die pattern  50  is formed in the shape of the pattern to be formed in the non-stick release coating applied to the pan blank  24 . The die pattern  50  may be formed in any desired shape. For exemplary purposes only, a die pattern  50  formed as a plate of magnetizable material shaped in a star pattern is illustrated in FIGS. 1 and 2. (It has been found that a star shaped pattern formed by reoriented metal flakes in a non-stick release coating applied to a pan provides improved heat distribution across the pan surface when the pan is used for cooking.) Alternatively, the die pattern  50  may be in the form of sheet metal bent into a desired pattern and mounted on the pan holding means  12  at an angle with respect to the plane of the underside of the pan blank  50  so that the upper edge, and not the face, of the sheet metal forms the pattern (i.e., the die pattern looks like a cookie cutter). The die pattern  50  is attached to the bottom support piece  16  of the pan holding means  12 , between the pan support rods  18 . Thus, when a pan blank  24  is held in position in the pan holding means  16  by the support rods  18 , the bottom outside surface of the pan blank  24  is held in contact with an upper surface of the die pattern  50 . As discussed previously, the support rods  18  function to hold the pan blank  24  in position in the pan holder  10 , and thus hold the pan blank  24  firmly in position with respect to the die pattern  50 . The die pattern  50  may be attached to the bottom support piece  16  in a conventional manner. 
     The magnet  52  may be a permanent magnet or an electromagnet. An exemplary permanent magnet which may be employed is Dexter Magnetics NEO-37 Alloy Rare Earth Magnet, Part. No. CM40978-3714. The magnet  52  may be attached directly to the die pattern  50 , to magnetize the die pattern  50 , thereby generating magnetic lines of force in the shape of the die pattern  50  through the pan blank  24  to the inside surface thereof. It has been found, however, that if the magnet  52  is coupled directly to the die pattern  50  background effects will be present in the magnetic field extending through the pan blank  24 . By background effects is meant magnetic force passing through the pan blank  24  which will operate on magnetizable flakes in a coating material applied to the inside of the pan blank  24  outside of the edges of the desired pattern, causing such flakes to move out of planer configuration. Such background effects cause unwanted fuzziness or increased darkness of the pattern edges. 
     Unwanted background effects can be reduced or eliminated if the magnetic force provided by the magnet  52  is diffused before being applied to the die pattern  50 . The magnetic force provided by the magnet  52  may preferably be diffused by interposing a spacer piece  54  between the magnet  52  and the die pattern  50 . The spacer piece  54  is preferably formed of a magnetic material and is sized so as to provide a desired degree of diffused magnetic force at the die pattern  50  to re-orient reflective magnetizable flakes distributed in a non-stick coating material applied to the inside of the pan blank  24  while eliminating background effects. The size of the spacer piece  54  and magnet  52  are preferably selected such that the area of the face of the magnet  52  is smaller than, and totally contained within, the area of the face of the spacer plate  54 , so that lines of force from the magnet  52  cannot pass directly to the pan blank  24  or other article being coated, thereby creating background effects. 
     The die pattern  50  may be attached to the spacer piece  54  in a conventional manner. For example, the spacer piece  50  may have a threaded hole  56  formed therethrough or thereon. The spacer piece  54  may have a corresponding threaded insert extending therefrom. The die pattern  50  may be attached to the spacer piece  54  by threading the die pattern hole  56  around the threaded insert extending from the spacer piece  54 . 
     The spacer piece  54 , in turn, may be attached to the bottom support piece  16  of the pan holding means  12  in a conventional manner. For example, as described previously, the bottom support piece  16  may be formed in a ring shape, having a central aperture formed therein. The spacer piece  54  may be mounted in the central aperture of the ring-shaped bottom support piece  16 . The spacer piece  54  may be securely attached to the bottom support piece  16  in a conventional manner. For example, a screw, bolt, or other fastener may be extended through a fastener hole  58  formed in the edge of the support piece ring  16  which is aligned with a similar fastener hole formed in a side of the spacer piece  54 . (As described previously, the bottom support piece  16  is preferably made of a non-magnetic material, e.g., aluminum, so as not to effect the magnetic force applied by the magnet  52  through the spacer piece  54  to the die pattern  50 .) 
     The magnet  52  is attached to an end of the spacer piece  54  opposite the die pattern  50 . The magnet  52  may be attached to the spacer piece  54  in a conventional manner. For example, where the spacer piece  54  is made of a magnetic material, magnetic attraction between the magnet  52  and the spacer piece  54  alone is sufficient to attach the magnet  52  to the spacer piece  54 . Alternatively, a conventional fastener structure may be used to attach the magnet  52  to the spacer piece  54 . 
     As illustrated in FIG. 2, the magnet  52  is preferably contained in a magnet housing  60 . The magnet housing  60  is preferably made of a non-magnetic material, such as Nylatron, or another plastic material. The magnet  52  is placed in a recess  62  formed in the upper surface of the magnet housing  60 . A thin piece of plastic  64  or other material may be positioned in a groove  66  formed around the recess  62  formed in the magnet housing  60 , to retain the magnet  52  in the recess  62 . 
     The magnet housing  60  may preferably have the same or similar diameter as the spacer piece  54 . The spacer piece  54  may be provided with a stepped bottom  68 , which corresponds in shape to a portion of the recess  62  formed in the magnet housing  60  which is not occupied by the magnet  52  or magnet retaining piece  66 . The magnet housing  60  may be attached in proper alignment to the spacer piece  54  by inserting the stepped bottom  68  of the spacer piece  54  into the recess  62  formed in the magnet housing  60 . The magnetic force provided by the magnet  52  holds the magnet  52  and the magnet housing  60  in position on the spacer piece  54 . A notch  70  or extending tab may be formed on the spacer piece with a corresponding tab or notch  72  formed on the magnet housing  60 . The tab or notch  70  on the spacer piece  54  is aligned with the notch or tab  72  formed in the magnet housing  60  when the magnet housing  60  is attached to the spacer piece  54 . Engagement between the notch and tab structures  70  and  72  on the spacer piece  54  and magnet housing  60  ensure proper alignment between the spacer piece  54  and magnet housing  60 , and further act to prevent rotation of the spacer piece  54  with respect to the magnet housing  60 . 
     The pan holder chuck  14 , including the shaft  46  and pulley  48 , may be attached to the bottom of the magnet housing  60 , opposite the end of the housing  60  which contains the magnet  52 . A recess  74  may be formed in the bottom of the magnet housing  16 , whereby the chuck  14  may be attached to the housing  60  by inserting an extending portion  75  of the chuck shaft  46  into the recess  74 , and securing the extending portion  75  of the shaft  46  in the recess  74  in a conventional manner, such as by threading the extending portion  75  of the shaft  46  into the recess  74 , or by using a screw, bolt, or other fastener to secure the extending portion  75  of the shaft  46  in the receptacle formed by the recess  74  in the magnet housing  60 . The chuck  14  also may be attached to the magnet housing  60  in any other conventional manner. 
     It is apparent that the spacing between the support rods  18  defines the size of the pan blank  24  which may be held in a pan holder  10  in accordance with the present invention. Of course, the support rods  18  may be spaced apart at any distance, to hold, for example, 7, 8, 10, or 12-inch diameter pan blanks  24  in the pan holder  10 . The height of the support rods  18  may also be optimized for holding pan blanks  24  of selected height between the support rods  18 . For example, the height of the support rods  18  may be selected to hold one quart or two quart capacity pan blanks  24 , or a griddle pan blank  24 . The position and height of the support rods  18  may be made adjustable, so that a particular pan holder  10  may be adjusted to hold variously sized pan blanks  24 . For example, the support rods  18  and/or support arms  20  may be made telescoping to adjust to the sizes thereof. Alternatively, the support rods  18  may be mounted in a fixed position on the pan holding means  16 , such that different pan holding means  16  are required to hold differently sized pan blanks  24 . 
     Where different pan holding means  16  are required to hold differently sized pan blanks  24 , considerable cost savings may be achieved if a single magnet  52  and chuck  14  may be used in combination with various different pan holding means  12  adapted to receive and hold variously sized pan blanks  24 . For this purpose, the magnet housing  60 , including the magnet  52 , and the chuck  14 , including the shaft  46  and pulley  48 , are preferably provided as a magnet/chuck assembly  76 , as illustrated in FIG.  2 . The magnet housing  60  of the magnet/chuck assembly  76  is preferably sized and shaped such that the magnet/chuck assembly  76  is adapted to be attached to various different pan holding means  12  adapted to hold variously sized pan blanks  24 . The bottom surfaces of the spacer pieces  54  employed in variously sized pan holding means  12  may have the same stepped or contoured bottom shape  68  and notch or tab structure  70  such that the universally adapted magnet/chuck assembly  76 , having a correspondingly shaped recess  62  and tab/notch structure  72  formed in the magnet housing  60  thereof, may be attached to the various pan holding means  12  via the spacer pieces  54 . Note that the magnet/chuck assembly  76  may be held in place on the spacer piece  54 , which is made of a magnetic material, by the magnetic force of the magnet  52  in the magnet housing  60 . The magnet  52  provides sufficient magnetic force to hold the magnet/chuck assembly  76  on the spacer piece  54  for most applications. For more demanding applications, a fastener, such as a screw, bolt, or other fastener, may be used to secure the magnet housing  60  to the spacer piece  54 . 
     A pan holder  10  in accordance with the present invention is used for holding a pan blank  24  during the process of applying a coating material to the pan blank  24 . A pan holder  10  in accordance with the present invention is particularly adapted for use on a chain-on-edge spray line. In a chain-in-edge spray line, a pan blank  24  is transported by a conveyor chain through various stations wherein a coating material is applied to the inner surface of the pan blank  24  by spraying the coating material thereon as the pan blank  24  is rotated. 
     A schematic illustration of an exemplary chain-on-edge spray line  78 , with which a pan holder  10  in accordance with the present invention is particularly adapted for use, is presented in FIG.  3 . The chain-on-edge spray line  78  employs a conveyor chain  80  for transporting pan blanks  24  through various coating material application and drying stations. The conveyor chain  80  includes a string of conveyor chain links  82  (only a portion of which are illustrated in FIG.  3 ). Each link  82  in the conveyor chain  80  has a central aperture  84  formed therein, which opens in an upward direction. The central aperture  84  in each conveyor chain link  82  is adapted to receive the shaft  46  extending from the chuck  14  of a pan holder  10  in accordance with the present invention. Multiple pan holders  10  in accordance with the present invention are mounted spaced apart on the conveyor chain  80 , by extending the chuck shaft  46  of each pan holder  10  through a central aperture  84  in one of the links  82  of the conveyor chain  80 . For exemplary purposes only, the conveyor chain  80  may be a 2½ inch pitch chain with chain links  82  positioned thereon such that every 2½ inches along the chain  80  there is a place to mount a pan holder chuck  14  to the chain  80 . (Only two pan holders  10  are shown mounted on the conveyor chain  80  in FIG. 3.) For exemplary purposes only,  55  pan holders  10  in accordance with the present invention may be mounted on a conveyor chain  80  in the manner described, with the centers of each pan holder  10  positioned on the conveyor chain  80  spaced approximately 18 inches apart. 
     An exemplary coating process employing a pan holder  10  in accordance with the present invention will now be described with reference to FIG.  3 . In this exemplary process, a non-stick release coating is formed on the inner surface of a pan blank  24 . A pattern is formed in the release coating by the magnetic re-orientation of reflective magnetizable metal flakes distributed in the release coating material. It should be understood that a pan holder  10  in accordance with the present invention may be used for other coating processes, and for applying coating materials to articles other than a pan blank  24  or another article of cookware. More details on the process of and materials used in the coating process to be described may be found in U.S. patent application Ser. Nos. 09/144,766 and 09/144,775, both filed on Sep. 1, 1998, the disclosures of which are incorporated herein by reference the first respective application now U.S. Pat. No. 6,103,361. 
     The coating application process begins by placing a pan blank  24  in a pan holder  10  in accordance with the present invention which is mounted on the conveyor chain  80 . As described previously, the pan holder  10  includes support rods  18  which hold the pan blank  24  in position on the pan holder  10 . The pan blank  24  may have pan handle studs  42  extending therefrom, which are preferably engaged by a handle stud engaging means  44  attached to a movable support arm  18 A. As described previously, the movable support arm  18 A is biased against an outer surface of the pan blank  24 , to hold the pan blank  24  in position against the other support rods  18 . The support rods  18  also hold the pan blank  24  in position against a magnetized die pattern  50  attached to the pan holder  10 . The pan blank  24  may be any size, provided that a pan holder  10  having support rods  18  of the appropriate height and spacing for holding the pan blank  24  in position is provided. The pan blank  24  may be made of any non-magnetizable material which can withstand the relatively high bake temperatures used to fuse the non-stick release coating materials which will be applied to the pan blank  24 . Such substrate materials include, for example, metals and ceramics, such as aluminum, anodized aluminum, stainless steel, enamel, glass, and pyrocerum, among others. 
     A pan blank  24  placed in a pan holder  10  in accordance with the present invention is transported by the conveyor chain  80 , in the direction indicated by arrow  86 , through a first station  88  wherein a primer coating material is applied to the interior surface of the pan blank  24 . A primer coating material is used to improve adhesion between a non-stick release coating material containing reflective magnetizable metal flakes and the surface of the pan blank substrate  24 . The use of a primer coating layer is optional, but is particularly important where the interior surface of the pan blank  24  is smooth, as preferred. Adhesion to the interior surface of the pan blank  24  can be improved if the interior surface is grit blasted (roughened) prior to coating. For pyrocerum and some glass, improved results are obtained by activation of the substrate surface such as by a slight chemical etch, which is not visible to the naked eye. The substrate can also be chemically treated with an adhesion agent, such as the mist coat of polyamic acid salt disclosed in U.S. Pat. No. 5,079,073 (Tannenbaum), hereby incorporated by reference. 
     The primer coating material, if used, may be derived from an aqueous dispersion of at least one fluoropolymer and a water soluble or water dispersible film-forming polymer binder material. Suitable primer materials are described in U.S. Pat. No. 4,014,834 (Concannon), U.S. Pat. No. 4,087,394 (Concannon), U.S. Pat. No. 5,240,775 (Tannenbaum), U.S. Pat. No. 5,250,356 (Batzar), and U.S. Pat. No. 5,562,991 (Tannenbaum). The film-forming polymer binding component that may be used in forming the primer coating is composed of a polymer which is thermally stable. This component is well known in primer applications for non-stick finishes, for adhering the fluoropolymer-containing primer layer to substrates and for film-forming within and as part of the primer layer. The binder is generally non-fluorine containing and yet adheres to both the fluoropolymer and the substrate. Preferred binders are those that are soluble or solubilized in water or a mixture of water and organic solvent for the binder, which solvent is miscible with water, although solvent-soluble polymer binders can be used in coating compositions in which the liquid vehicle is organic solvent. This solubility aids in the blending of the binder with the fluorocarbon component in the aqueous dispersion form. Polyethersulfone is one example of a thermally stable polymer binder. A preferred binder component is polyamic acid salt, which converts to polyamideimide upon baking of the composition to form the primer layer. An inorganic filler film hardener component may also be present in the primer composition. The film hardener is one or more filler type materials which are inert with respect to the other components of the composition and thermally stable at baking temperatures which fuse the fluoropolymer and binder. Preferably the film hardener is water insoluble so that it is uniformly dispersible but not dissolved in an aqueous dispersion. Examples of a film hardener include one or more metal silicate compounds, such as aluminum silicate, and metal oxides, such as titanium dioxide and aluminum oxide. The primer composition, in aqueous dispersion form, may also contain such other additives as adhesion promoters, such as colloidal silica, or a phosphate compound, such as a metal phosphate, e.g., Zn, Mn, or Fe phosphate. 
     The primer material, in liquid form, is applied to the interior surface of the pan blank  24  by spraying the material from a nozzle (not shown) onto the interior surface of the pan blank  24  in the primer application station  88 . (The primer coating, when used, may be applied to a thickness of 0.5 to 10 micrometers.) To ensure an even application of the primer material onto the pan blank  24 , the pan blank  24  is rotated while the primer material is sprayed onto the interior surface thereof. The pan blank  24  is rotated by a drive belt  90 . The drive belt  90  is positioned in the primer application station  88  adjacent to the conveyor chain  80  such that the pulley  48  on the chuck  14  of the pan holder  10  is engaged by the drive belt  90  when the pan holder  10  transported through the primer application station  88  by the conveyor chain  80 . The moving drive belt  90  engages the pulley  48  to rotate the pan holder  10 , and the pan blank  24  held therein, about the chuck shaft  46 . As the pan holder  10  is transported by the moving conveyor chain  80  out of the primer application station  88 , the pulley  48  is disengaged from the drive belt  90 , and rotation of the pan holder stops. 
     Following the primer application station  88 , the conveyor chain  80  transports the pan holder  10 , with the pan blank  24  held therein, through a drying tunnel  92 . In the drying tunnel  92 , hot air, such as hot air heated by steam, is used to dry the primer coating material applied to the interior surface of the pan blank  24  in the primer application station  88 . Since the pan blank  24  need not be rotated in the drying tunnel  92 , a drive belt  90  is not provided therein. 
     After the primer coating material has been dried in the drying tunnel  92 , the conveyor chain  80  transports the pan blank  24  through an intermediate coating application station  94 , wherein a non-stick release coating material having reflective magnetizable flakes dispersed therein is applied to the interior surface of the pan blank  24 , over the primer coating layer. The intermediate coating layer material may be applied in a manner similar to that by which the primer coating material was applied, i.e., by spraying the intermediate non-stick release coating material onto the interior surface of the pan blank  24  while rotating the pan blank  24 . Thus, as in the primer coating application station  88 , a drive belt  96  is provided in the intermediate coating application station  94 , to engage the pulley  48  on the pan holder  10 , thereby to rotate the pan holder  10 , and the pan blank  24  held therein, while the intermediate coating material is applied thereto. 
     The intermediate release coating material applied to the pan blank  24  in the intermediate coating material application station  94  is preferably a liquid fluoropolymer composition containing magnetizable flakes. The fluoropolymer component is generally commercially available as a dispersion of polymer in water, which is the preferred form of the composition for ease of application and environmental acceptability. The fluoropolymer/flake coating composition is preferably derived from a dispersion of one or more fluoropolymers to which has optionally been added a dispersion of an acrylic polymer. Exemplary fluoropolymer materials which may be employed for the intermediate coating are described in U.S. Pat. No. 4,180,609 (Vassiliou), U.S. Pat. No. 4,118,537 (Vary &amp; Vassiliou), U.S. Pat. No. 4,123,401 (Berghmans &amp; Vary), and U.S. Pat. No. 4,351,882 (Concannon), hereby incorporated by reference. Acrylic polymer dispersions are described in U.S. Pat. No. 4,123,401 (Berghmans &amp; Vary) and U.S. Pat. No. 4,118,537 (Vary &amp; Vassilou), hereby incorporated by reference. The reflective flakes used in the release coating material should be made of a material which, while magnetizable, is ineffected by the high temperatures (350° C. to 420° C.) required to sinter or otherwise fuse the fluoropolymer material forming the release coating. Examples of materials from which the flakes can be made include such metals as iron and nickel and alloys containing these metals, with stainless steel being the preferred material. The magnetizable flakes preferably include flakes which have a longest dimension which is slightly greater than the thickness of the layer formed from the coating composition which contains the flakes. The intermediate coating thickness will generally be from 5 to 40 micrometers. The flake size will then depend on the coating thickness desired. 
     The magnetizable flakes in the intermediate layer of coating material will naturally align themselves parallel with the surface of the interior of the pan blank  24  to which the material is applied. However, while the coating of fluoropolymer composition containing the magnetizable flakes is still liquid, the flakes are mobile, and thus can be re-oriented perpendicular to the interior pan blank surface by an applied magnetic force. In this case, the magnet  52 , spacer piece  54 , and die pattern  50  act to apply a magnetic force in the shape of the die pattern  50  to the coating composition simultaneously with the application of the liquid coating composition to the pan blank  24 . This provides the best opportunity for obtaining perpendicular flake re-orientation. The reoriented reflective magnetizable flakes thus create a pattern, in the shape of the die pattern  50 , in the intermediate release coating layer. As discussed previously, since the pan holder  10  of the present invention holds the pan blank  24  in position with respect to the die pattern  50 , so as to prevent movement of the pan blank  24  with respect to the die pattern  50  during the application of the intermediate non-stick coating material containing the magnetizable flakes thereto, a distinct, sharp-edged pattern is formed in the intermediate release coating layer, i.e., fuzziness of the created pattern is minimized. 
     After the intermediate release coating material, including the re-oriented reflective magnetizable flakes, is applied to the pan blank  24  at the intermediate coating application station  94 , the pan blank  24  may be transported through a top coat application station  98 , wherein a top coat of non-stick release coating material is applied over the intermediate coating layer. The top coat material may be applied over the intermediate coating layer in the same manner as the primer and intermediate coating materials are applied, i.e., the top coat material may be sprayed onto the interior of the pan blank  24 , over the intermediate coating, as the pan blank  24  is rotated. Thus, a drive belt  100  is provided in the top coat application station  98  to engage the pulley  48  attached to the pan holder  10 , to thereby rotate the pan blank  24  held therein. 
     The composition forming the top coat layer is preferably the same as or similar to the non-stick release coating material applied as the intermediate coating layer, but without the magnetizable metal flakes dispersed therethrough. The top coat layer may be applied to a thickness of 2.5 to 10 micrometers. The top coat layer provides additional protection and wear resistance over the non-stick intermediate release coating, and smoothes out the interior surface of the pan blank  24  where vertically re-oriented flakes in the intermediate release coating which are longer than the thickness of the intermediate release coating protrude therefrom. The composition forming the top coat may contain mica particles, or mica particles coated with pigment. Such particles impart scratch resistance to the articles on which they are coated. Exemplary mica particles coated with pigment which may be employed are described in U.S. Pat. No. 3,087,827 (Klenke and Stratton), U.S. Pat. No. 3,087,828 (Linton), and U.S. Pat. No. 3,087,829 (Linton), hereby incorporated by reference. 
     It should be noted that the compositions forming the primer, intermediate, and top coatings may also contain one or more pigments, normally in a mill-base medium that is either soluble in or miscible with the water of the fluoropolymer aqueous dispersion. Pigments for use in cookware applications have limitations imposed on their use by the U.S. Food and Drug Administration (FDA) because of food contact. Pigments to be used in cookware must be heat stable and non-toxic. Suitable pigments include at least one member from the group of: carbon black, titanium dioxide, iron oxide, and zeolites, such as ultra marine blue, and cobalt blue, among others. Preferably, the amount of pigment included in the intermediate and top coatings is sufficient to add a color tone to the non-stick release coating applied to the interior surface of the pan blank  24 , without obscuring the pattern formed by the re-oriented reflective magnetizable flakes in the intermediate coating layer. 
     After the top coat has been applied to the pan blank in the top coat application station  98 , the pan blank  24  may be removed from the pan holder  10  for drying and baking of the coating layers applied thereto, to sinter or otherwise fuse the fluoropolymer layers to form the release coating, by heating the coating layers typically to temperatures of 350° C. to 420° C., depending on the fluoropolymer resins used. The pan blank  24  may then be further processed in a conventional manner to complete the article of cookware. 
     It should be understood that the present invention is not limited to the particular exemplary embodiments and applications illustrated and described herein, but embraces all modified forms thereof as come within the scope of the following claims.