Decorative grip and method for making

A decorative grip system including a decorative grip having a label with decorative indicia located thereon, the label being formed in a generally closed shape. The decorative grip system further includes an underlay layer located generally inside of the label and a generally translucent overlay layer located generally outside of the label and having a thickness of less than about 5/32 inch.

The present invention is directed to a grip and a method for manufacturing a grip, and more particularly, to a grip having decorative features and a method for manufacturing a grip having decorative features.

BACKGROUND

Golf grips are typically made of wrapped leather, molded natural leather or molded solid colored synthetic materials. Such materials limit the ability to incorporate graphics and color into the grips due to the relatively dark color of the materials, as well as the difficulties of printing on such materials. As an alternative, the outer surface of golf grips may be etched or molded to form a recess and the recessed area may be filled with paint or other colorants to provide basic designs and patterns. However, this method for forming decorative patterns is difficult to implement, expensive to manufacture, and lacks durability.

Another method for creating a golf club with graphics displayed in the grip area involves attaching a printed label directly to the club shaft and sliding a clear (i.e. “water-clear”—which has a lower light tranmisivity than, for example “ultra-clear”) thermoplastic grip shell over the attached label such that the attached label is visible through the clear thermoplastic grip. However, this type of decorative grip is cumbersome and difficult to assemble. In particular, in order to assemble such a grip, the golf club shaft must first be cleaned to a like-new condition such that the shaft is free of all tape and residue from any previous grips. A label-type sticker bearing the decorative features is then wrapped over the clean shaft, and great care must be taken at this time to align the sticker so that the sticker is properly centered in relation to the central vertical axis of the shaft. Care must also be taken not to wrinkle the sticker during such application.

The sticker is then sprayed with a sealant such as hairspray or the like, and the sealant is also sprayed onto the inside of a clear thermoplastic grip shell. The clear grip shell is then slid over the label, while taking care not to move or wrinkle the label underneath. The walls of the grip shell must be relatively thick to ensure that the grip shell does not rupture during the assembly process and to provide the necessary thickness to the finished grip.

This multi-step process for assembling a decorative grip is labor intensive and inefficient. Furthermore, a drawback to a golf grip assembled in this manner is that the grip shell is relatively thick which limits the visibility of the decorative label, distorts the graphics, and thereby reduces aesthetic appeal. Specifically, the thickness of the water-clear thermoplastic grip creates a hazing effect, thereby reducing aesthetic appeal. Additionally, the thickness of the grip wall can produce an angle of refraction thereby distorting the visible features of the decorative label.

Accordingly, there is a need for a grip for a component, such as a golf club, which has decorative features yet which is durable and robust. There is also a need for a method for forming such a grip.

SUMMARY

The present invention is a decorative grip which is durable and robust. In particular, in one embodiment, the invention is a decorative grip system including a decorative grip having a label with decorative indicia located thereon, the label being formed in a generally closed shape. The decorative grip system further includes an underlay layer located generally inside of the label and a generally translucent overlay layer located generally outside of the label and having a thickness of less than about 5/32 inch.

In another embodiment the invention is a decorative grip system including a decorative grip having a label with decorative indicia located thereon, the label being formed in a generally closed shape. The decorative grip system further includes an underlay layer located generally inside of the label and a generally translucent overlay layer located generally outside of the label. The decorative grip is formed in a generally tubular shape and includes a central opening for receiving a component to be gripped therein. The decorative grip includes a pair of ends, one of the ends being an open end to provide access to the central opening, the other one of the ends being generally closed.

In another embodiment the invention is a decorative grip system including a decorative grip having a label with decorative indicia located thereon, the label being formed in a generally closed shape. The decorative grip system further includes an underlay layer located generally inside of and fused to the label, and a generally translucent overlay layer located generally outside of the label.

In another embodiment the invention is a method for manufacturing a decorative grip system including the steps of providing a label having decorative indicia located thereon and forming the label into a generally closed shape. The method further includes the steps of forming an underlay layer inside the label and forming a generally translucent overlay layer outside of the label.

These and other objects and advantages of the present invention will be apparent from the following description, the accompanying drawings and the appended claims.

DETAILED DESCRIPTION

FIGS. 1-11illustrate one set of steps which may be utilized to manufacture the decorative grip or handle of the present invention.FIGS. 1-11show the steps for manufacturing a single grip, although it should be understood that a number of grips may be simultaneously manufactured in bulk manner. It should also be understood that the grip of the present invention can be manufactured by a wide variety of methods, and the method shown herein is merely one illustrative example. Furthermore, various ones of the steps disclosed herein may be reversed or carried out in the various orders besides the specific order disclosed herein.

As shown inFIG. 1, the process may begin by first printing or creating a decorative label10by printing a decorative design12on a substrate14to form the decorative label10. The decorative design12may include any of a wide variety of decorative features, including text, patterns, pictures, photographs, logos, slogans, designs, drawings, artwork, colors, sketches, etc. The decorative design12can be created by a wide variety of manners, includes graphic design computer programs, freehand drawing, computer generated images, digital or analog photographs, prints or the like. In the illustrated example, the decorative design12is the text “Underscore Golf.”

The substrate14upon which the decorative design12is printed may be any of a wide variety of materials, and may be a microporous silica-based printing sheet, or a microporous, highly filled polyethylene matrix printing sheet (for example, a sheet of TESLIN® material manufactured by PPG Industries, Inc. of Pittsburgh, Pa.), and may have a thickness of between about 1 and about 100 mils, preferably about 10 mils. The substrate14may be microporous so that the substrate14can readily absorb ink, dyes, etc. printed thereon. The substrate14may also have a relatively low coefficient of friction so that injection molded material can flow smoothly across the surface of the decorative label10. The decorative design12may be deposited or printed on the substrate14by any of a wide variety of printing methods, such as digital printing, flexographic printing, lithography, graveure printing, etc.

The decorative label10is then coated with a protective coating (not shown) on the printed surface of the substrate14/decorative label10to stabilize the ink on the substrate14to improve durability for subsequent handling. The protective coating may be a UV protective or UV resistant material to provide extensive UV resistance to the substrate14. The protective coating may include UV energy cross-linkable coatings that reduce the tendency of the substrate14to stretch during injection molding. For example, the coating may be a lacquer-type coating, or a clear, transparent or translucent variant of an ink optimized for microporous sheets, such as GRA-C501 and the GRA series of coatings available from Pinnacle Products Group, Ltd. of Dayton Ohio.

If not already cut to the desired shape, the decorative label10is then cut into the desired shape by any desired manner, such as die cutting. The decorative label10may take any of a wide variety of shapes and sizes. However, in the illustrated embodiment, the decorative label10is generally rectangular having a pair of opposed end edges16,18and a pair of opposed longitudinal edges20,22, and may have dimensions of about 10 inches by about 3 inches or various other dimensions as desired. If desired, the decorative label10may be formed with fold lines24, or fold lines24may be created on the decorative label10after printing. The decorative label10may include more or less fold lines than those shown inFIG. 1.

Next the decorative label10is folded outwardly about the fold lines24to form the decorative label10into a generally closed shape (i.e., a generally cylindrical or tube shape), as shown inFIG. 2. It should be noted that the term “tubular” as used herein means a generally closed shape and does not denote any particular shape in cross section. Thus a tubular shape may include components that are generally circular, square, triangular, hexagonal, irregular, etc. in cross section.

If desired, the decorative label10may be folded about a mandrel to aid in the folding process at this step. The decorative label10may be folded such that the decorative design12/protective coating is on the outer surface of the folded decorative label10. The folded decorative label10may be folded or shaped to generally match the shape of the component to which the grip will be mounted, such as, for example, the shaft of a golf club.

Once the decorative label10is folded, the outer longitudinal edges20,22of the decorative label10may overlap slightly (by, for example, about 1-2 mm) and may be adhered together by any of a variety of methods. For example, a narrow line of acid free, photo-safe permanent adhesive may be applied at various spaced points26(i.e., about four to about seven points as shown inFIG. 3) along the length of the overlapping edges20,22to secure the overlapping edges20,22together, to thereby provide the decorative label10as shown inFIG. 3. The steps of folding the decorative labels10and adhering the overlapping edges20,22may be carried out either manually or by an automated process, or by some combination thereof.

The folded printed decorative label10is then placed into a cavity injection mold30, such as that shown inFIG. 4. The illustrated mold30includes two mold halves32,34which, when brought together, join seamlessly to form a mold inner cavity36. As shown inFIGS. 4 and 5, the mold cavity36includes a label-receiving portion38which is sized and located to generally closely receive the folded label10therein. The label-receiving portion38is defined by and located between a pair of radially inwardly-extending flanges40that extend circumferentially about the mold cavity36. The mold cavity36further includes an end cap portion42(located axially outside one of the flanges40) and a grip collar portion44located axially outside the other flange40. The mold cavity36may include an open end46located adjacent to the grip collar portion44and a closed end48located adjacent to the end cap portion42. The closed end48may have an end protrusion50extending into the mold cavity. The end protrusion50may include a relief opening (not shown) formed therein to provide pressure relief during the molding process36.

The mold cavity36and label10are shown as having a straight (i.e., non-tapered) shape. However, it should be understood that the mold cavity36and label10may have a variety of shapes, includes angled (i.e. tapered) cylinders, tubes, etc.

With reference toFIG. 5, when the label10is inserted into the mold cavity36, the label10is generally closely received in the label-receiving portion38and held between the flanges40(FIG. 5illustrates the label10somewhat spaced away from the walls66of the mold cavity36and from the flanges40for illustrative purposes; in actuality the label10may be quite closely received in the mold cavity36). The label10should be inserted into the mold cavity36such that the overlapping edges20,22are not aligned with the split39in the mold30(i.e., where the two mold halves32,34join), and the label10may have a registration mark printed thereon to ensure the label10is properly aligned in the mold cavity36.

Once the label10is properly located inside the mold cavity36, a core pin52is inserted into the mold cavity36and received through the label10(FIG. 6). The core pin52is generally solid and includes a central artery or central opening54, and includes relatively small end relief opening60at its distal end58that is aligned with and receives the end protrusion50therein.

The core pin52also includes an injection opening or gate62communicating with the central opening54. The gate62may form an angle with the central axis of the core pin52. The angle may have a wide variety of ranges, such as between about 0 degrees and about 65 degrees, preferably about 5 degrees. As will be discussed in greater detail below, the angled nature of the gate62directs injected material towards the closed end48of the mold cavity36. The gate62may be located at or generally adjacent to the open end46of the mold cavity36. In particular, the gate62may be located within about 1 inch, or within about 3 inches of the open end46of the mold cavity36. Thus the gate62may be adjacent to the open end46such that the gate62is located within a distance of about 5% or about 30% of the length of the mold cavity36from the open end46of the mold cavity36. The gate62may also be located within a distance of about 5%, or about 30%, of the length of the core pin52from the open end46.

After the core pin52is inserted into the mold cavity36and through the label10, the core pin52is then locked into position (i.e., by securing the core pin52to one of the mold halves32,34). The mold halves32,34are then brought together to close the mold, and the mold30is locked shut. When the mold30is locked shut, it is desired that the outer surface of the label10rest against the cavity wall66. The shape, size and curve of the label10should match that of the cavity wall66to ensure that the label10is kept stable during the injection molding process. Further, because the outer surface of the core pin52defines the inner diameter of the finished grip, the outer diameter and shape of the core pin52should be carefully selected to provide the desired shape to the inner diameter of the finished grip.

The material which is desired to form the inner portion of the molded grip (i.e., the underlay material70) is then injection molded into the mold cavity36via the core pin52. The injected material70may be any of a wide variety of materials which have sufficient flexibility and can be injection molded, including, but not limited to, thermoplastic materials, vulcanizable rubbers, or thermoplastic elastomers such as DYNAFLEX® thermoplastic rubber or elastomer sold by GLS Corporation of McHenry, Ill. or ®SANTOPRENE® thermoplastic elastomer made by Advanced Elastomer Systems of Akron, Ohio. The injection molded material70forms an underlay layer that, when cured, may have a hardness of between about 20 Shore A and about 60 Shore A or 55 Shore A.

The injection-molded material70may be injected at temperatures of about 190° F. and about 400° F. and at pressures between about 50 psi and about 500 psi. The injection molded material70may be a non-metallic material and may have nearly any desired thickness, such as, for example, greater than or less than about 1/64″ greater than or less than about 1/32″, greater than or less than about 1/16″, greater than or less than about ⅛″, greater or less than about 5/32″, greater than or less than about ¼″ or greater than or less than about ½″.

The injection-molded material70is introduced under pressure into the core pin52and fills the central opening54and exits through the gate62. As the injected material70is injected into the mold cavity36via the gate62, the injected material70impinges against the inner surface of the label10and presses the label10against the wall66of the cavity36(FIG. 7). The injected material70progressively moves along the length of the mold cavity36, forcing the label10against the inner wall66of the mold cavity36as the injected material70moves toward the closed end48. As noted above, although the label10may already lie flush against the inner wall66of the mold cavity36,FIGS. 5-7illustrate the label10slightly spaced away from the inner wall66of the mold cavity36such that the label10is forced against the inner wall66of the mold cavity36by the injected material70during the injection process.

Because the gate62is located near the open end46of the mold cavity36and is angled to inject material toward the closed end48, the gate62forces the injected material70away from the open end46until the closed end48is filled. Once the closed end48and the end cap42portion of the mold cavity36are filled with injection material70, the front (or collar portion44) of the mold cavity36is filled with the injected material70.

This arrangement and location of the gate62helps to ensure that introduction of the injected material70between the label10and wall66at the axial ends of the mold cavity36is minimized. In particular, if the injected material70were to be inserted between the label10and the cavity wall66, the injected material70would block the visibility of part of the label10and the appearance of the grip would be degraded. Because the injected material70is injected at a location relatively remote from the edge18, by the time the injected material70reaches the edge18the majority of the length of the label10has been pressed against the wall66of the mold cavity. Accordingly, when the injected material70reaches the edge18, it is difficult to peel the edge18away from the cavity wall66such that the introduction of the injected material70between the label10and the wall66is minimized. Similarly, by the time the injected material70reaches the edge16, nearly the entire label10is pressed against the wall66, thereby reducing the chance for the injected material to be forced between edge16and cavity wall66. Thus by the time the injected material reaches the label edges16,18, the risk of the injected material70overtaking the label edges will have been greatly diminished.

The end flanges40trap the label10therebetween during the molding process, and thereby contribute to the stability of the molding process. Thus, the end flanges40, the precision sizing and placement of the label10within the mold cavity36, the position and angle of the gate62and the rate of flow of material70through the gate62helps to securely retain the label10in position, and eliminates the need to hold the label10in place through other means, such as electrostatic energy. As the hot injected material70presses against the label10, the injected material chemically reacts with the interior surface of the label (i.e. the substrate14), thereby permanently fusing the label10and injected material70(as described in, for example, U.S. Pat. No. 6,544,634, the contents of which are hereby incorporated by reference).

In those areas of the cavity36where the label10is not located (i.e., the end cap portion42and the collar portion44), the injected material70fills those recesses of the mold cavity36to form the end cap82and grip collar84of the grip80(FIG. 8). The timing of the molding cycle is continuously monitored and adjusted to account for changes in the interior and exterior mold temperatures. Thus, a mold cycle can last for any of a wide variety of times, such as between about 5 and about 90 seconds. Once the mold cavity36is completely filled with injectable material70, the flow of material70through the core pin52and gate62is terminated, and the mold halves32,34are opened. The core pin52is then retracted from the mold cavity36(FIG. 9) and the formed grip80is removed from the mold30, thereby resulting in the grip80shown inFIG. 10having a central opening81.

The molded grip80may then be treated with an overlay material90to protect the printed label10from ambient conditions and friction of use, and also to provide an improved tactile material for gripping. The overlay90may be made of any of a wide variety of materials which provide the desired tactile feel and are generally transparent, translucent, or see-through, such as, for example, a clear, translucent or transparent elastomer or thermoplastic material having a hardness of between 30 Shore A and55or 60 Shore A, or less than about 60 Shore A, or less than about 55 Shore A, or less than about 30 Shore A. The overlay material90may have a sufficient light transparency so as to be classified as “ultra-clear.” The overlay material90may have a thickness of greater than or less than about ¼″, or greater than or less than about 5/32″, or greater than or less than about ⅛″, or greater than or less than about 1/16″, or greater than or less than about 1/32″. The overlay material90may bond or be bonded to the label10.

The overlay material90may be made of a wide variety of materials, including but not limited to silicone rubber, synthetic polyisoprene, polyurethane, a clear, translucent or transparent thermoplastic elastomer alloy such as VERSAFLEX® thermoplastic rubber sold by GLS Corporation of McHenry, Ill., a clear, translucent or transparent thermoplastic elastomer, KRATON® thermoplastic rubber sold by Shell Oil Company of Houston, Tex., or OPTIFLEX™ material sold by Star Thermoplastic Alloy & Rubbers, Inc. of Chicago, Ill. The overlay material90may be silicon, such as a medical grade silicon, deposited on the grip80by an extrusion method, or other generally transparent or translucent materials with the desired tactile properties. The overlay material90may have a soft or tacky feel to aid a user of the grip, and may have UVA/UVB protective qualities to further protect the decorative design12of the label10from sun or light damage, in addition to acting as a protectant to minimize the effects of solvents and perspiration on the label10.

The overlay90may be located on the grip80by a wide variety of methods, including but not limited to depositing the overlay90in an overmolding process. In particular, a second mold may be provided such that the freshly molded grip80, while still located on the core pin52from the original molding process, can be inserted into a second (overmolding) mold machine. The overlay material90may then be shot into the mold cavity and directly onto the decorated surface of the grip80. In this case only the decorated portions of the grip80(i.e. the portions of the grip80located radially adjacent to the decorative label10) may be coated with the overmold. Alternately, the entire outer surface of the grip80(including the surfaces of the end cap82and the grip collar84) may be coated with the overlay material90. Further alternately, the overlay material90may first be molded to the decorative (outer) surface of the label10prior to the molding of the underlay layer70to the inner surface of the label10. The overlay material90may be located on the entire outer surface of the grip80, or may be located only between the end cap82and grip collar84, as shown inFIG. 11.

Rather than overmolding the overlay material90, the overlay material90may be deposited simply by dipping the grip80in a liquid vat of overlay material90or spraying the grip with the overlay material90or the like. The overlay90is then allowed to cure (for example, at room temperature). If desired, the end cap82and grip collar84of the grips80may be masked off while depositing the overlay material90to ensure that the overlay material90covers only the decorative surface of the grip80. Because the decorative surface (i.e., adjacent to the label10) may be radially recessed with respect to the end cap82and grip collar84, the deposited overlay material90may have a thickness equal to that of the recess such that the overlay material90is generally flush with the end cap82and grip collar84(as shown inFIG. 10). As can be seen the end cap82and grip collar84extend beyond the label10, which has a length extending in the axial direction. Although the end cap82and grip collar84may have any of a variety of lengths, in one embodiment the injected material or underlay layer70has a length extending in said axial direction that is less than about 150%, or less than about 120% of the length of said label10.

Once the grips80are molded and the overlay material90is formed thereon, the grips80may be shipped to a customer/end user. In addition, or alternately, the grips80may then be slipped over the gripping surface of a component, such as a golf club (including putters, irons and woods). In the case of golf clubs, because the grip80of the present invention may be shaped to fit over a standard golf club shaft86, the grip may be mounted or applied using standard instrumentation and method of traditional golf grip application (i.e. simply lubricating the golf or club shaft and/or placing a lubricating two-ply tape around the golf club shaft and sliding the grip over the end of the shaft).FIG. 12illustrates a finished grip80. The end cap82of the grip80shown inFIG. 12is somewhat shorter than the end cap82shown inFIGS. 8-11.FIG. 13illustrates the grip80mounted onto the shaft86of a golf club88. The inner diameter of the grips may be equal to or slightly smaller than the diameter of the shaft to which the grip is mounted to ensure a tight fit.

Thus, the method of the present invention provides grips having high quality printed graphic designs with durable performance-enhancing tactile gripping surface in a one-piece standard installation golf grip. In particular, the grips can display high-resolution photographic images, graphic designs, logos, colors, and/or text. Furthermore, the grips may be covered by a thin, transparent or translucent overlay material that allows the images, designs, colors or text to be visible through the overlay material with minimal thickness and therefore minimal distortion. The overlay material protects the images, designs, color and text from the abrasive effects of gripping and aging due to exposure to the elements, and also serves as a primary gripping surface.

Besides golf grips, the method of the present invention, and the grips themselves, may be utilized in a wide variety of devices and industries, including but not limited to, bicycles, tool handles, kitchen utensils, appliances, motor vehicles, racket sports, etc.

Having described the invention in detail and by reference to the preferred embodiments, it will be apparent that modifications and variations thereof are possible without departing from the scope of the invention.