Golf Club Head

This disclosure relates generally to golf clubs, and more particularly to a wood-type golf club head having a high-mass, high-volume sole-mounted weight.

Modern “wood-type” golf clubs (notably, “drivers,” “fairway woods,” and “utility or hybrid clubs”), are generally called “metalwoods” since they tend to be made of strong, lightweight metals, such as titanium. An exemplary metalwood golf club, such as a driver or fairway wood, typically includes a hollow shaft and a golf club head coupled to a lower end of the shaft. Most modern versions of driver-type club heads are made, at least in part, from a lightweight but strong metal, such as a titanium alloy. In most cases, the golf club head is includes a hollow body with a face portion. The face portion has a front surface, known as a strike face, configured to contact the golf ball during a proper golf swing.

Some fairway woods are made of a titanium alloy. However, shortcomings in conventional titanium alloys require thicker walls and additional reinforcements to ensure the fairway woods are durable enough to withstand repeated impacts with a golf ball. These compensations for the shortcomings of conventional titanium alloys can have a negative impact on the performance of the golf club head. For example, thicker walls and additional reinforcements can undesirably raise the center-of-gravity of the golf club head.

The subject matter of the present application has been developed in response to the present state of the art, and in particular, in response to the shortcomings of golf clubs and associated golf club heads, that have not yet been fully solved by currently available techniques. Accordingly, the subject matter of the present application has been developed to provide a golf club and golf club head that overcome at least some of the above-discussed shortcomings of prior art techniques.

In some examples, the golf club heads of the present disclosure help to improve performance characteristics of wood-type golf club heads by, for example, lower the center-of-gravity of the golf club heads. The center-of-gravity is lowered by making a body of the golf club head out of a material with a lower density and attaching a large weight, made of a higher density material, to the sole of the golf club head. The particular size, shape, and mass of the large weight, relative to the size, shape, and mass of the body, results in a golf club head that achieved improved performance and durability over conventional golf club heads.

Disclosed herein are examples of a golf club head that comprises a body, defining an interior cavity. The body also comprises a sole portion, positioned at a bottom region of the golf club head, a crown portion, positioned at a top region of the golf club head, a skirt portion, positioned around a periphery of the golf club head between the sole portion and the crown portion, and a face portion, positioned at a forward region of the golf club head, opposite a rearward region of the golf club head, and extending from a toe region to a heel region of the golf club head. At least a portion of the body is made of a titanium alloy. The golf club head also comprises a large weight, coupled to the sole portion of the body and made of a steel alloy. A mass of the large weight is at least 40% of a mass of the portion of the body made of the titanium alloy. A total mass of the large weight and the portion of the body made of the titanium alloy is at least 210 grams.

Also disclosed herein are examples of a golf club head that comprises a body, made of a first material having a first material density and comprising a face portion. The golf club head also comprises a large weight, attached to the body and made of a second material having a second material density. A ratio of the second material density to the first material density is at least 1.70, inclusive. The second material of the large weight has a mass that is at least 23%, inclusive, of a mass of the first material of the body. At least 60%, inclusive, of a total mass of the large weight is forward of a theoretical forward-rearward midplane (MP3) of the golf club head that extends parallel to an x-axis of a golf club head origin coordinate system of the golf club head at a midpoint between a forwardmost point of the golf club head and a rearwardmost point of the golf club head. The body comprises a weight mating recess, configured to receive at least a portion of the large weight. The weight mating recess has a depth that varies in a direction away from the face portion of the body. The depth of the weight mating recess is greater proximal the face portion than distal the face portion.

Additionally disclosed herein are examples of a golf club that comprises a shaft comprising a butt end and a tip end. The golf club further comprises a golf club head comprising a body, defining an interior cavity of the golf club head, and further comprising a sole defining a bottom portion of the golf club head, a crown defining a top portion of the golf club head, a skirt portion defining a periphery of the golf club head between the sole and the crown, a face defining a forward portion of the golf club head, and a hosel defining a hosel bore. The body further comprises a shaft attachment port positioned in the sole and extending into the interior cavity. The shaft attachment port has a port width and is located proximate a bottom end of the hosel such that a passage in the bottom end of the hosel provides communication between the hosel bore and the shaft attachment port. The golf club additionally comprises a sleeve mounted on the tip end of the shaft and adapted to be inserted into the hosel bore. The golf club further comprises a fastener having a head portion located in the shaft attachment port and a shaft portion extending through the passage. The shaft portion is selectively attachable to the sleeve when the sleeve is inserted into the hosel bore. The golf club head further comprises a weight attached to a sole portion of the body and defining at least a portion of the sole of the golf club head. The golf club head also comprises a weight recess formed in the sole portion of the body of the golf club head and extending into the interior cavity of the golf club head. The weight recess is configured to receive at least a portion of the weight. The weight recess has a variable depth. At least a portion of the weight recess is located proximate the shaft attachment port. A depth of the weight recess proximate the face is greater than the depth of the weight recess distal the face. The golf club head has an overall height less than about 45 millimeters (mm). The golf club head has a total volume between about 120 cubic centimeters (cc) and about 240 cc inclusive.

Also disclosed herein are examples of a golf club head that comprises a body, comprising a face portion and defining an interior cavity. The golf club head further comprises a large weight that is attached to the body. The body is made of a first material having a first material density of no more than 8 g/cc. The large weight is made of a second material having a second material density of no less than 7 g/cc. The first material density is less than the second material density. A ratio of the second material density to the first material density is at least 1.70, inclusive. At least 60%, inclusive, of a total mass of the large weight is forward of a theoretical forward-rearward midplane (MP3) of the golf club head that extends parallel to an x-axis of a golf club head origin coordinate system of the golf club head at a midpoint between a forwardmost point of the golf club head and a rearwardmost point of the golf club head. The body comprises a weight mating recess, configured to receive at least a portion of the large weight. The weight mating recess has a depth that varies in a direction away from the face portion of the body. The depth of the weight mating recess is greater proximal the face portion than distal the face portion. At least a portion of the large weight crosses the theoretical forward-rearward midplane (MP3) of the golf club head. The large weight has a volume of at least 3 cubic centimeters, inclusive. The large weight defines a portion of a sole of the golf club head. The large weight defines at least 6 square centimeters of a surface area of the sole.

The described features, structures, advantages, and/or characteristics of the subject matter of the present disclosure may be combined in any suitable manner in one or more examples and/or implementations. In the following description, numerous specific details are provided to impart a thorough understanding of examples of the subject matter of the present disclosure. One skilled in the relevant art will recognize that the subject matter of the present disclosure may be practiced without one or more of the specific features, details, components, materials, and/or methods of a particular example or implementation. In other instances, additional features and advantages may be recognized in certain examples and/or implementations that may not be present in all examples or implementations. Further, in some instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the subject matter of the present disclosure. The features and advantages of the subject matter of the present disclosure will become more fully apparent from the following description and appended claims, or may be learned by the practice of the subject matter as set forth hereinafter.

The following describes examples of golf club heads in the context of a fairway wood golf club head, but the principles, methods and designs described may be applicable in whole or in part to drivers, utility clubs (also known as hybrid clubs), and the like.

U.S. Patent Application Publication No. 2014/0302946 A1 ('946 App), published Oct. 9, 2014, which is incorporated herein by reference in its entirety, describes a “reference position” similar to the address position used to measure the various parameters discussed throughout this application. The address or reference position is based on the procedures described in the United States Golf Association and R&A Rules Limited, “Procedure for Measuring the Club Head Size of Wood Clubs,” Revision 1.0.0, (Nov. 21, 2003). Unless otherwise indicated, all parameters are specified with the club head in the reference position.

are examples that show a golf club headin the address position, i.e. the golf club headis positioned such that a hosel axisof the golf club headis at a 60-degree lie angle relative to a ground planeand a strike faceof the golf club headis square relative to an imaginary target line. As shown in, positioning the golf club headin the reference position lends itself to using a club head origin coordinate systemfor making various measurements. Additionally, the USGA methodology may be used to measure the various parameters described throughout this application including head height, club head center of gravity (CG) location, and moments of inertia (MOI) about the various axes.

For further details or clarity, the reader is advised to refer to the measurement methods described in the '946 App and the USGA procedure. Notably, however, the origin and axes used in this application may not necessarily be aligned or oriented in the same manner as those described in the '946 App or the USGA procedure. Further details are provided below on locating the club head origin coordinate system.

The golf club headdescribed herein may be a driver-type golf club head with a relatively large strike face of at least 3500 mm{circumflex over ( )}2, preferably at least 3800 mm{circumflex over ( )}2, and even more preferably at least 3900 mm{circumflex over ( )}2. Additionally, the golf club head may include a center of gravity (CG) projection proximate center facethat may be at most 3 mm above or below center faceof the strike face, and preferably may be at most 1 mm above or below center face, as measured along a vertical axis (z-axis). Moreover, the golf club headmay have a relatively high moment of inertia about the vertical z-axis e.g. Izz>350 kg-mm{circumflex over ( )}2 and preferably Izz>400 kg-mm{circumflex over ( )}2, a relatively high moment of inertia about the horizontal x-axis e.g. Ixx>200 kg-mm{circumflex over ( )}2 and preferably Ixx>250 kg-mm{circumflex over ( )}2, and preferably a ratio of Ixx/Izz>0.55.

In other examples, the golf club headis a fairway-type golf club head with a strike face that is relatively smaller than a driver-type golf club head. For example, the strike facehas an area of at least 1,500 mm{circumflex over ( )}2 and at most 3,000 mm{circumflex over ( )}2, in some implementations. Furthermore, in some examples, the loft of the golf club headis between 15-degrees and 30-degrees, inclusive. Additionally, in certain examples, the golf club headhas a CG projection proximate center facethat may be at most 5 mm above or below center faceof the strike face, and preferably may be at most 3 mm above or below center face, as measured along a vertical axis (z-axis). Moreover, the golf club headmay have a moment of inertia about the vertical z-axis (e.g. Izz>150 kg-mm{circumflex over ( )}2 and Izz<370 kg-mm{circumflex over ( )}2, or Izz>180 kg-mm{circumflex over ( )}2 and Izz<300 kg-mm{circumflex over ( )}2) and a moment of inertia about the horizontal x-axis (e.g. Ixx). In certain examples, Izz is at least 1.5 times Ixx, such as at least 1.75 times Ixx. Additionally, the golf club headof these examples may have a Zup value that is greater than about 20 mm.

The golf club headdisclosed herein may have a volume equal to the volumetric displacement of the bodyof the golf club head. For example, the golf club headof the present application can be configured to have a head volume between about 110 cmand about 600 cm, such as greater than 150 cm. In more particular examples, the head volume may be between about 120 cmand about 240 cmor between about 250 cmand about 500 cm. In yet more specific embodiments, the head volume may be between about 300 cmand about 500 cm, between about 300 cmand about 360 cm, between about 300 cmand about 420 cmor between about 420 cmand about 500 cm. In the case of a driver, the golf club headmay have a volume between about 300 cmand about 460 cm, and a total mass between about 145 grams (g) and about 245 g. In the case of a fairway wood, the golf club headmay have a volume between about 100 cmand about 250 cm, and a total mass between about 145 g and about 260 g. In the case of a utility or hybrid club the golf club headmay have a volume between about 60 cmand about 150 cm, and a total mass between about 145 g and about 280 g.

Referring to, the golf club headof the present disclosure includes a body. The bodyhas a toe regionand a heel region, opposite the toe region. Additionally, the bodyincludes a forward regionand a rearward region, opposite the forward region. The bodyfurther includes a face portionat the forward regionof the body. The bodyof the golf club headadditionally includes a sole portion, at a bottom regionof the golf club headand at least partially defining a soleof the golf club head, and a crown portion, opposite the sole portionand at a top regionof the golf club headand defining a crown of the golf club head. Also, the bodyof the golf club headincludes a skirt portionthat defines a transition region where the bodyof the golf club headtransitions between the crown portionand the sole portion. Accordingly, the skirt portionis located between the crown portionand the sole portionand extends about a periphery of the golf club headto define a skirt of the golf club head. The face portionextends along the forward regionfrom the sole portionto the crown portion. Moreover, the exterior surface, and at least a portion of the interior surface, of the face portionis planar in a top-to-bottom direction. As further defined, the face portionis the portion of the bodyat the forward regionwith an exterior surface that faces in the generally forward direction.

In some examples, as shown in, the face portionincludes a front apertureand a strike platecoupled to and closing the front aperture. The strike platedefines a strike faceconfigured to impact and drive the golf ball during a normal swing of the golf club head. In certain implementations, the strike plateis made from the same material as or a different material than a cast frameof the bodyto which the strike plateis attached. For example, the strike platecan be made from a first titanium alloy and the cast framecan be made from a second titanium alloy that is different than the first titanium alloy. Although inthe strike plateis formed separately from a cast frameof the bodyand attached (e.g., welded, braised, soldered, screwed, or otherwise coupled) to the cast frame, in other examples, the strike faceis co-formed (e.g., co-cast) with the cast frameto form the face portionof the bodyas a one-piece monolithic construction with the cast frame.

In some examples, the strike faceincludes undulations as shown and described in U.S. patent application Ser. No. 16/160,974, filed Oct. 15, 2018, and U.S. patent application Ser. No. 16/160,884, filed Oct. 15, 2018, which are both incorporated herein by reference in their entirety.

The cast frameis the portion of the bodythat is made of metal and cast as a single one-piece monolithic construction. Generally, the cast frameprovides a framework or skeleton of the golf club headto strengthen the golf club headin areas of high stress caused by the impact of a golf ball with the face portion. Such areas include a transition region where the golf club headtransitions from the face portionto the crown portion, the sole portion, and the skirt portionof the body. As shown in, internal surfaces of the cast framepartially defines the interior cavityof the golf club head. The internal surfaces of the cast frameincludes several interconnected surfaces that are angled relative to each other. According to one example, the golf club headhas no internal ribs intercoupling or extending between any two interconnected surfaces, of the internal surfaces of the cast frame, that are angled relative to each other. In other words, the cast frameis rib-less. As defined herein a rib is a tall and thin structure with a height or length that is at least 2-times, at least 3-times, or at least 4-times a thickness of the structure and with a height that is at least 1.5 mm. Normally, ribs are required to stiffen a golf club head and to dampen the acoustics of the golf club head when impacted by a golf ball. However, because the large weight, described below, helps to stiffen the golf club headand dampen the acoustics of the golf club head, no ribs are necessary. Moreover, because ribs add mass to the golf club head, getting rid of the ribs increases the discretionary mass of the golf clubthat can be relocated to other areas of the golf club headfor improving the performance of the golf club head.

When cast together, the strike faceand the cast frameare made of the same material, such as any of various materials described below. However, welding a strike plateto the cast frame, as opposed to co-forming the strike faceas a one-piece construction with the cast frame, allows the strike plateand strike faceto be made from a different material, such as any of those described below, and/or made by a different manufacturing process, than the cast frame. According to certain implementations, the forward regionof the body, defining the strike face, includes variable thickness features similar to those described in more detail in U.S. patent application Ser. No. 12/006,060; and U.S. Pat. Nos. 6,997,820; 6,800,038; and 6,824,475, which are incorporated herein by reference in their entirety.

The golf club headalso includes a hoselextending from the heel regionof the golf club head. As shown in, a tip end of a shaftof a golf clubmay be attached directly to the hoselor, alternatively, attached indirectly to the hosel, such as via a flight control technology (FCT) component(e.g., an adjustable lie/loft assembly) coupled with the hosel. The golf clubalso includes a grip fitted around a distal end or butt end of the shaft. The grip of the golf clubhelps promote the handling of the golf clubby a user during a golf swing. The hosel axis, which is coaxial with the shaft, defining a central axis of the hosel.

In some examples, the bodyof the golf club headincludes one or more inserts coupled to the cast frame. For example, the crown portionof the bodyincludes a crown insertattached to the cast frameat the top regionof the golf club head. For example, the cast frameof the bodyincludes a crown apertureor crown opening, sized and configured to receive the crown insert. The crown aperturereceives and fixedly secures the crown insert. The crown apertureis formed to have a peripheral lipor recess to seat the crown insert, such that the crown insertis either flush with the cast frameto provide a smooth seamless outer surface or, alternatively, slightly recessed. It is recognized that in some examples, instead of a crown insert, an entirety of the crown portionis co-formed with the cast frameto form a one-piece monolithic construction with the cast frame.

In some examples, the body(e.g., just the cast frameof the body) and/or the face portionis made of a titanium alloy (including but not limited to 9-1-1, 6-4, 3-2.5, 6-4, SP700, 15-3-3-3, 10-2-3, or other alpha/near alpha, alpha-beta (e.g., ZA1300), and beta/near beta titanium alloys) or mixtures thereof. In one example, the titanium alloy of the bodyis a 9-1-1 titanium alloy. Titanium alloys comprising aluminum (e.g., 8.5-9.5% Al), vanadium (e.g., 0.9-1.3% V), and molybdenum (e.g., 0.8-1.1% Mo), optionally with other minor alloying elements and impurities, herein collectively referred to a “9-1-1 Ti”, can have less significant alpha case, which renders HF acid etching unnecessary or at least less necessary compared to faces made from conventional 6-4 Ti and other titanium alloys. Further, 9-1-1 Ti can have minimum mechanical properties of 820 MPa yield strength, 958 MPa tensile strength, and 10.2% elongation. These minimum properties can be significantly superior to typical cast titanium alloys, such as 6-4 Ti, which can have minimum mechanical properties of 812 MPa yield strength, 936 MPa tensile strength, and ˜6% elongation. In certain examples, the titanium alloy is 8-1-1 Ti.

In another example, the titanium alloy of the bodyis an alpha-beta titanium alloy comprising 6.5% to 10% Al by weight, 0.5% to 3.25% Mo by weight, 1.0% to 3.0% Cr by weight, 0.25% to 1.75% V by weight, and/or 0.25% to 1% Fe by weight, with the balance comprising Ti (one example is sometimes referred to as “1300” or “ZA1300” titanium alloy). In another representative example, the alloy may comprise 6.75% to 9.75% Al by weight, 0.75% to 3.25% or 2.75% Mo by weight, 1.0% to 3.0% Cr by weight, 0.25% to 1.75% V by weight, and/or 0.25% to 1% Fe by weight, with the balance comprising Ti. In yet another representative example, the alloy may comprise 7% to 9% Al by weight, 1.75% to 3.25% Mo by weight, 1.25% to 2.75% Cr by weight, 0.5% to 1.5% V by weight, and/or 0.25% to 0.75% Fe by weight, with the balance comprising Ti. In a further representative example, the alloy may comprise 7.5% to 8.5% Al by weight, 2.0% to 3.0% Mo by weight, 1.5% to 2.5% Cr by weight, 0.75% to 1.25% V by weight, and/or 0.375% to 0.625% Fe by weight, with the balance comprising Ti. In another representative example, the alloy may comprise 8% Al by weight, 2.5% Mo by weight, 2% Cr by weight, 1% V by weight, and/or 0.5% Fe by weight, with the balance comprising Ti (such titanium alloys can have the formula Ti-8A1-2.5Mo-2Cr-1V-0.5Fe). As used herein, reference to “Ti-8A1-2.5Mo-2Cr-1V-0.5Fe” refers to a titanium alloy including the referenced elements in any of the proportions given above. Certain embodiments may also comprise trace quantities of K, Mn, and/or Zr, and/or various impurities.

Ti-8A1-2.5Mo-2Cr-1V-0.5Fe can have minimum mechanical properties of 1150 MPa yield strength, 1180 MPa ultimate tensile strength, and 8% elongation. These minimum properties can be significantly superior to other cast titanium alloys, including 6-4 Ti and 9-1-1 Ti, which can have the minimum mechanical properties noted above. In some embodiments, Ti-8A1-2.5Mo-2Cr-1V-0.5Fe can have a tensile strength of from about 1180 MPa to about 1460 MPa, a yield strength of from about 1150 MPa to about 1415 MPa, an elongation of from about 8% to about 12%, a modulus of elasticity of about 110 GPa, a density of about 4.45 g/cm, and a hardness of about 43 on the Rockwell C scale (43 HRC). In particular examples, the Ti-8A1-2.5Mo-2Cr-1V-0.5Fe alloy can have a tensile strength of about 1320 MPa, a yield strength of about 1284 MPa, and an elongation of about 10%. The Ti-8Al-2.5Mo-2Cr-1V-0.5Fe alloy, particularly when used to cast golf club head bodies, promotes less deflection for the same thickness due to a higher ultimate tensile strength compared to other materials. In some implementations, providing less deflection with the same thickness benefits golfers with higher swing speeds because over time the strike faceof the golf club headwill maintain its original shape over time.

According to some examples, the face portionis made of a first alloy of a first material and other portions of the bodyare made of a second alloy of the first material. The first alloy is different than the second alloy. For example, the first alloy can be ZA 1300 titanium alloy and the second alloy can be 6-4 titanium alloy. In another example, the first alloy is 9-1-1 titanium alloy and the second alloy is 6-4 titanium alloy. Accordingly, in some examples, the ultimate tensile strength (UTS) of the titanium alloy of the face portionis greater than (e.g., 10% greater than) the UTS of the titanium alloy of the body. In certain examples, the material of the face portionhas a UTS greater than 1,000 MPa, greater than 1,100 MPa, or greater than 1,200 MPa, and the material of the bodyhas a UTS less than 1,100 MPa or less than 1,000 MPa. According to some examples, the material of the face portionand the material of the bodyinclude aluminum such that the mass percentage of aluminum in the face portionis greater than 7% and the mass percentage of aluminum in the bodyis less than 7%. In certain examples, the difference in the mass percentage of aluminum in the material of the face portionand the mass percentage of aluminum in the material of the bodyis at least 0.5%. According to some examples, the material of the face portionand the material of the bodyinclude molybdenum such that the mass percentage of molybdenum in the face portionis greater than 1.9% and the mass percentage of molybdenum in the bodyis less than 1.9%.

In certain examples described in this paragraph, the strike platehas a thickness of between 2.6 mm and 2.8 mm, such as 2.7 mm, or between 2.8 mm and 3.0 mm, such as 2.9 mm. Correspondingly, a thickness of the face portion, at locations above the strike plateand within 20 mm toeward and heelward of centerface, is between 2.5 mm and 2.7 mm, such as 2.6 mm, or between 2.7 mm and 2.9 mm, such as 2.8 mm. A thickness of the face portion, at locations below the strike plateand within 10 mm toeward and heelward of centerface, is between 2.4 mm and 2.6 mm, such as 2.5 mm, or between 2.6 mm and 2.8 mm, such as 2.7 mm. A thickness of the face portion, at locations below the strike plateand at least 20 mm toeward and heelward of centerface, is between 1.7 mm and 1.9 mm, such as 1.8 mm, or between 1.9 mm and 2.1 mm, such as 2.0 mm. A thickness of the face portion, at locations heelward and toeward of the strike plate, is between 1.7 mm and 1.9 mm, such as 1.8 mm, or between 1.9 mm and 2.1 mm, such as 2.0 mm.

According to some examples, the crown insertand/or the face portionare formed of a non-metal material with a density less than about 2 g/cc, such as between about 1 g/cc to about 2 g/cc. The non-metal material may include a polymer or polymer-reinforced composite material (e.g., a carbon fiber material having a matrix made of the non-metal material). The polymer can be either thermoset or thermoplastic, and can be amorphous, crystalline and/or a semi-crystalline structure.

The polymer may also be formed of an engineering plastic such as a crystalline or semi-crystalline engineering plastic or an amorphous engineering plastic. Potential engineering plastic candidates include polyphenylene sulfide ether (PPS), polyamides, polypropylene, thermoplastic polyurethanes, thermoplastic polyureas, polyamide-amides (PAI), polyethelipide (PEI), polycarbonate (PC), polypropylene (PP), acrylonitrile-butadience styrene plastics (ABS), polyoxymethylene plastic (POM), nylon 6, nylon 6-6, nylon 12, polymethyl methacrylate (PMMA), polypheylene oxide (PPO), polybothlene terephthalate (PBT), polysulfone (PSU), polyether sulfone (PES), polyether ether ketone (PEEK) or mixtures thereof. Organic fibers, such as fiberglass, carbon fiber, or metallic fiber, can be added into the engineering plastic, so as to enhance structural strength. The reinforcing fibers can be continuous long fibers or short fibers. One of the advantages of PSU is that it is relatively stiff with relatively low damping which produces a better sounding or more metallic sounding golf club compared to other polymers which may be overdamped. Additionally, PSU requires less post processing in that it does not require a finish or paint to achieve a final finished golf club head.

Other polymeric materials may include, without limitation, synthetic and natural rubbers, thermoset polymers such as thermoset polyurethanes or thermoset polyureas, as well as thermoplastic polymers including thermoplastic elastomers such as thermoplastic polyurethanes, thermoplastic polyureas, metallocene catalyzed polymer, unimodalethylene/carboxylic acid copolymers, unimodal ethylene/carboxylic acid/carboxylate terpolymers, bimodal ethylene/carboxylic acid copolymers, bimodal ethylene/carboxylic acid/carboxylate terpolymers, polyamides (PA), polyketones (PK), copolyamides, polyesters, copolyesters, polycarbonates, polyphenylene sulfide (PPS), cyclic olefin copolymers (COC), polyolefins, halogenated polyolefins [e.g. chlorinated polyethylene (CPE)], halogenated polyalkylene compounds, polyalkenamer, polyphenylene oxides, polyphenylene sulfides, diallylphthalate polymers, polyimides, polyvinyl chlorides, polyamide-ionomers, polyurethane ionomers, polyvinyl alcohols, polyarylates, polyacrylates, polyphenylene ethers, impact-modified polyphenylene ethers, polystyrenes, high impact polystyrenes, acrylonitrile-butadiene-styrene copolymers, styrene-acrylonitriles (SAN), acrylonitrile-styrene-acrylonitriles, styrene-maleic anhydride (S/MA) polymers, styrenic block copolymers including styrene-butadiene-styrene (SBS), styrene-ethylene-butylene-styrene, (SEBS) and styrene-ethylene-propylene-styrene (SEPS), styrenic terpolymers, functionalized styrenic block copolymers including hydroxylated, functionalized styrenic copolymers, and terpolymers, cellulosic polymers, liquid crystal polymers (LCP), ethylene-propylene-diene terpolymers (EPDM), ethylene-vinyl acetate copolymers (EVA), ethylene-propylene copolymers, propylene elastomers (such as those described in U.S. Pat. No. 6,525,157, to Kim et al, the entire contents of which is hereby incorporated by reference), ethylene vinyl acetates, polyureas, and polysiloxanes and any and all combinations thereof.

Of these preferred are polyamides (PA), polyphthalimide (PPA), polyketones (PK), copolyamides, polyesters, copolyesters, polycarbonates, polyphenylene sulfide (PPS), cyclic olefin copolymers (COC), polyphenylene oxides, diallylphthalate polymers, polyarylates, polyacrylates, polyphenylene ethers, and impact-modified polyphenylene ethers. Especially preferred polymers for use in the golf club heads of the present invention are the family of so called high performance engineering thermoplastics which are known for their toughness and stability at high temperatures. These polymers include the polysulfones, the polyethelipides, and the polyamide-imides. Of these, the most preferred are the polysufones.

Aromatic polysulfones are a family of polymers produced from the condensation polymerization of 4,4′-dichlorodiphenylsulfone with itself or one or more dihydric phenols. The aromatic polysulfones include the thermoplastics sometimes called polyether sulfones, and the general structure of their repeating unit has a diaryl sulfone structure which may be represented as -arylene-SO2-arylene-. These units may be linked to one another by carbon-to-carbon bonds, carbon-oxygen-carbon bonds, carbon-sulfur-carbon bonds, or via a short alkylene linkage, so as to form a thermally stable thermoplastic polymer. Polymers in this family are completely amorphous, exhibit high glass-transition temperatures, and offer high strength and stiffness properties even at high temperatures, making them useful for demanding engineering applications. The polymers also possess good ductility and toughness and are transparent in their natural state by virtue of their fully amorphous nature. Additional key attributes include resistance to hydrolysis by hot water/steam and excellent resistance to acids and bases. The polysulfones are fully thermoplastic, allowing fabrication by most standard methods such as injection molding, extrusion, and thermoforming. They also enjoy a broad range of high temperature engineering uses.

Three commercially important polysulfones are a) polysulfone (PSU); b) Polyethersulfone (PES also referred to as PESU); and c) Polyphenylene sulfoner (PPSU).

Particularly important and preferred aromatic polysulfones are those comprised of repeating units of the structure —C6H4SO2-C6H4-O— where C6H4 represents a m- or p-phenylene structure. The polymer chain can also comprise repeating units such as —C6H4—, C6H4-O—, —C6H4-(lower-alkylene)-C6H4-O—, —C6H4-O-C6H4-O—, —C6H4-S—C6H4-O—, and other thermally stable substantially-aromatic difunctional groups known in the art of engineering thermoplastics. Also included are the so called modified polysulfones where the individual aromatic rings are further substituted in one or substituents including

wherein R is independently at each occurrence, a hydrogen atom, a halogen atom or a hydrocarbon group or a combination thereof. The halogen atom includes fluorine, chlorine, bromine and iodine atoms. The hydrocarbon group includes, for example, a C1-C20 alkyl group, a C2-C20 alkenyl group, a C3-C20 cycloalkyl group, a C3-C20 cycloalkenyl group, and a C6-C20 aromatic hydrocarbon group. These hydrocarbon groups may be partly substituted by a halogen atom or atoms, or may be partly substituted by a polar group or groups other than the halogen atom or atoms. As specific examples of the C1-C20 alkyl group, there can be mentioned methyl, ethyl, propyl, isopropyl, amyl, hexyl, octyl, decyl and dodecyl groups. As specific examples of the C2-C20 alkenyl group, there can be mentioned propenyl, isopropepyl, butenyl, isobutenyl, pentenyland hexenyl groups. As specific examples of the C3-C20 cycloalkyl group, there can be mentioned cyclopentyl and cyclohexyl groups. As specific examples of the C3-C20 cycloalkenyl group, there can be mentioned cyclopentenyl and cyclohexenyl groups. As specific examples of the aromatic hydrocarbon group, there can be mentioned phenyl and naphthyl groups or a combination thereof.

Individual preferred polymers include (a) the polysulfone made by condensation polymerization of bisphenol A and 4,4′-dichlorodiphenyl sulfone in the presence of base, and having the main repeating structure

and the abbreviation PSF and sold under the tradenames Udel®, Ultrason® S, Eviva®, RTP PSU, (b) the polysulfone made by condensation polymerization of 4,4′-dihydroxydiphenyl and 4,4′-dichlorodiphenyl sulfone in the presence of base, and having the main repeating structure

and the abbreviation PPSF and sold under the tradenames RADEL® resin; and (c) a condensation polymer made from 4,4′-dichlorodiphenyl sulfone in the presence of base and having the principle repeating structure

and the abbreviation PPSF and sometimes called a “polyether sulfone” and sold under the tradenames Ultrason® E, LNP™, Veradel®PESU, Sumikaexce, and VICTREX® resin,” and any and all combinations thereof.

In some embodiments, a composite material, such as a carbon composite, made of a composite including multiple plies or layers of a fibrous material (e.g., graphite, or carbon fiber including turbostratic or graphitic carbon fiber or a hybrid structure with both graphitic and turbostratic parts present). Examples of some of these composite materials for use in the metalwood golf clubs and their fabrication procedures are described in U.S. patent application Ser. No. 10/442,348 (now U.S. Pat. No. 7,267,620), Ser. No. 10/831,496 (now U.S. Pat. No. 7,140,974), Ser. Nos. 11/642,310, 11/825,138, 11/998,436, 11/895,195, 11/823,638, 12/004,386, 12,004,387, 11/960,609, 11/960,610, and 12/156,947, which are incorporated herein by reference. The composite material may be manufactured according to the methods described at least in U.S. patent application Ser. No. 11/825,138, the entire contents of which are herein incorporated by reference.

Alternatively, short or long fiber-reinforced formulations of the previously referenced polymers can be used. Exemplary formulations include a Nylon 6/6 polyamide formulation, which is 30% Carbon Fiber Filled and available commercially from RTP Company under the trade name RTP 285. This material has a Tensile Strength of 35000 psi (241 MPa) as measured by ASTM D 638; a Tensile Elongation of 2.0-3.0% as measured by ASTM D 638; a Tensile Modulus of 3.30×106 psi (22754 MPa) as measured by ASTM D 638; a Flexural Strength of 50000 psi (345 MPa) as measured by ASTM D 790; and a Flexural Modulus of 2.60×106 psi (17927 MPa) as measured by ASTM D 790.

Other materials also include is a polyphthalamide (PPA) formulation which is 40% Carbon Fiber Filled and available commercially from RTP Company under the trade name RTP 4087 UP. This material has a Tensile Strength of 360 MPa as measured by ISO 527; a Tensile Elongation of 1.4% as measured by ISO 527; a Tensile Modulus of 41500 MPa as measured by ISO 527; a Flexural Strength of 580 MPa as measured by ISO 178; and a Flexural Modulus of 34500 MPa as measured by ISO 178.

Yet other materials include is a polyphenylene sulfide (PPS) formulation which is 30% Carbon Fiber Filled and available commercially from RTP Company under the trade name RTP 1385 UP. This material has a Tensile Strength of 255 MPa as measured by ISO 527; a Tensile Elongation of 1.3% as measured by ISO 527; a Tensile Modulus of 28500 MPa as measured by ISO 527; a Flexural Strength of 385 MPa as measured by ISO 178; and a Flexural Modulus of 23,000 MPa as measured by ISO 178.

Especially preferred materials include a polysulfone (PSU) formulation which is 20% Carbon Fiber Filled and available commercially from RTP Company under the trade name RTP 983. This material has a Tensile Strength of 124 MPa as measured by ISO 527; a Tensile Elongation of 2% as measured by ISO 527; a Tensile Modulus of 11032 MPa as measured by ISO 527; a Flexural Strength of 186 MPa as measured by ISO 178; and a Flexural Modulus of 9653 MPa as measured by ISO 178.