Golf Club Heads with a Multi-Material Striking Surface

This is a continuation of U.S. patent application Ser. No. 18/596,055, filed on Mar. 5, 2024, which is a continuation of U.S. patent application Ser. No. 17/816,633, filed on Aug. 1, 2022, now U.S. Pat. No. 11,918,864, issued on Mar. 5, 2024, which claims the benefit of U.S. Provisional Patent Application No. 63/203,817, filed on Jul. 30, 2021, and is a continuation-in-part of U.S. patent application Ser. No. 17/645,267, filed on Dec. 20, 2021, now U.S. Pat. No. 12,280,301, issued on Apr. 22, 2025, which is a continuation of U.S. patent application Ser. No. 16/983,924, filed on Aug. 3, 2020, now U.S. Pat. No. 11,207,572, issued on Dec. 28, 2021, which claims the benefit of U.S. Provisional Patent Application No. 62/881,463, filed on Aug. 1, 2019, and U.S. Provisional Patent Application No. 63/046,505, filed on Jun. 30, 2020, the contents of all of which are entirely incorporated herein by reference.

This disclosure relates generally to golf club heads and more particularly to a putter-type golf club head with a multi-material striking surface.

As golf clubs are the sole instruments that set golf balls in motion during play, the golf industry has seen improvements in putters and golf club head designs in recent years. However, it is known, that when it comes to designing putter-type club heads, golfers tend to prioritize personal preference characteristics (i.e. club head feel, club head aesthetics, club head sound etc.) over performance.

To putt a golf ball in the hole, a golfer must successfully impact the golf ball (with a golf club head and more particularly a putter-type golf club head) at a proper speed and face angle. This provides a challenge to all golfers, as many struggle to consistently impact the golf ball at the same location putt after putt. Striking the golf ball at various locations on the putter-type club head can alter the amount of energy transferred from the putter head to the golf ball during initial contact, impact feel, impact sound and/or travel direction of the golf ball. Specifically, variation in strike location can cause differences in ball speed across the striking surface, causing putts to travel unpredictable distances. There is a need in the art to create a putter-type golf club head that balances golfers' personal preference characteristics while considering various impact locations.

Directed herein are golf club heads, and in particular, a putter-type golf club heads comprising a striking surface capable of achieving consistent ball speeds across the striking surface to account for various ball impact locations. This striking surface has at least two materials that differs in concentration away from the geometric center (or center region) of the striking surface to provide this consistency. Consistent (or uniform) ball speed is achieved throughout the striking surface as the portion of the golf ball that contacts the striking surface interacts with at least two materials having a differing material property (or characteristic).

The differing material property can be (but not an exhaustive list of) tensile strength, flexural modulus, or material hardness. A uniform ball speed is accomplished by the combination of a dual material striking surface and varying the amount of the first material and/or the second material away from the geometric center (or center region) of the striking surface. In many embodiments, the first and second material cooperate to form a softer, more flexible center region and opposing the center region either in a heel or toe direction, the first and second material cooperate to form a harder, stiffer, and less flexible region. This is because contact outside the geometric center of the striking surface (or club head sweet spot) results in less energy transfer from the club head to the golf ball.

Creating a center region that is less responsive than the corresponding heel and toe regions can be accomplished in many ways. For example, in embodiments, where a first soft material dominates a less soft second material, a less responsive center region can be formed. In other embodiments, a less responsive center region can be formed by controlling the void and/or recess patterns to form larger first material land areas at the center region than at adjacent heel and toe regions.

The term or phrase “lie angle” used herein can be defined as being the angle between a golf shaft (not shown) and a playing surface once the sole contacts the playing surface. The lie angle of a golf club head can also be referred to as the angle formed by the intersection of the centerline of the golf shaft and the playing surface when the sole of the golf club head is resting on the playing surface.

The term or phrase “integral” used herein can be defined as two or more elements if they are comprised of the same piece of material. As defined herein, two or more elements are “non-integral” if each element is comprised of a different piece of material.

The term or phrase “couple”, “coupled”, “couples”, and “coupling” used herein can be defined as connecting two or more elements, mechanically or otherwise. Coupling (whether mechanical or otherwise) can be for any length of time, e.g. permanent or semi-permanent or only for an instant. Mechanical coupling and the like should be broadly understood and include mechanical coupling of all types. The absence of the word “removably,” “removable,” and the like near the word “coupled,” and the like does not mean that the coupling, in question is or is not removable.

The term or phrase “head weight” or “head mass” used herein can be defined as the total mass or weight of the putter.

The term or phrase “attach”, “attached”, “attaches, and “attaching” used herein can be defined as connecting or being joined to something. Attaching can be permanent or semi-permanent. Mechanically attaching and the like should be broadly understood and include all types of mechanical attachment means. Integral attachment means should be broadly understood and include all types of integral attachment means that permanently connects two or more objects together.

The term or phrase “loft angle” used herein can be defined as the angle between the striking surface and the golf shaft. In other embodiments, the loft angle can be defined herein as such: the striking surface comprises a striking surface center point and a loft plane. The striking surface center point is equidistant from (1) the lower edge and upper edge of the strike face, as well as, (2) equidistant from the heel end and toe end of strike face. The loft plane is tangent to the strike surface of the putter type golf club head. The golf shaft comprises a centerline axis that extends the entire length of the golf shaft. The loft angle is between the centerline axis of the golf shaft and the loft plane of the putter. The loft angle of the putter-type golf club head can also be defined herein as the angle between the striking surface and the golf shaft (not shown) when a centerline of the golf shaft is generally vertical (i.e. forms a generally 90° angle with the playing surface).

The terms “first,” “second,” “third,” “fourth,” and the like in the description and in the claims, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein. Furthermore, the terms “include,” and “have,” and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, device, or apparatus that comprises a list of elements is not necessarily limited to those elements but may include other elements not expressly listed or inherent to such process, method, system, article, device, or apparatus.

The terms “left,” “right,” “front,” “back,” “top,” “bottom,” “over,” “under,” and the like in the description and in the claims, if any, are used for descriptive purposes and not necessarily for describing permanent relative positions. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the apparatus, methods, and/or articles of manufacture described herein are, for example, capable of operation in other orientations than those illustrated or otherwise described herein.

The term “center region” can be defined as the region on the striking surface that includes the geometric center. The center region can extend from the upper border of the striking surface to the lower border of the striking surface and have a heel-to-toe span of approximately 0.1 inch, 0.2 inch, 0.3 inch, 0.4 inch, 0.5 inch, 0.6 inch, 0.7 inch, 0.8 inch, 0.9 inch, 1.0 inch, 1.1 inch, 1.2 inch, 1.3 inch, 1.4 inch, 1.5 inch, 1.6 inch, 1.7 inch, 1.8 inch, 1.9 inch, or 2.0 inch.

The term “heel region” can be defined as the region on the striking surface that extends from the heel end of the striking surface (and/or club head) up to the center region heel side border. The term “toe region” can be defined as the region on the striking surface that extends from the toe end of the striking surface (and/or club head) up to the center region toe side border.

“A,” “an,” “the,” “at least one,” and “one or more” are used interchangeably to indicate that at least one of the item is present; a plurality of such items may be present unless the context clearly indicates otherwise. All numerical values of parameters (e.g., of quantities or conditions) in this specification, including the appended claims, are to be understood as being modified in all instances by the term “about” whether or not “about” actually appears before the numerical value. “About” indicates that the stated numerical value allows some slight imprecision (with some approach to exactness in the value; about or reasonably close to the value; nearly). If the imprecision provided by “about” is not otherwise understood in the art with this ordinary meaning, then “about” as used herein indicates at least variations that may arise from ordinary methods of measuring and using such parameters. In addition, disclosure of ranges includes disclosure of all values and further divided ranges within the entire range. Each value within a range and the endpoints of a range are hereby all disclosed as separate embodiment. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated items, but do not preclude the presence of other items. As used in this specification, the term “or” includes any and all combinations of one or more of the listed items. When the terms first, second, third, etc. are used to differentiate various items from each other, these designations are merely for convenience and do not limit the items.

In many examples as used herein, the term “approximately” can be used when comparing one or more values, ranges of values, relationships (e.g., position, orientation, etc.) or parameters (e.g., velocity, acceleration, mass, temperature, spin rate, spin direction, etc.) to one or more other values, ranges of values, or parameters, respectively, and/or when describing a condition (e.g., with respect to time), such as, for example, a condition of remaining constant with respect to time. In these examples, use of the word “approximately” can mean that the value(s), range(s) of values, relationship(s), parameter(s), or condition(s) are within ±0.5%, ±1.0%, ±2.0%, ±3.0%, ±5.0%, and/or ±10.0% of the related value(s), range(s) of values, relationship(s), parameter(s), or condition(s), as applicable.

Before any embodiments of the disclosure are explained in detail, it is to be understood that the disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The disclosure is capable of other embodiments and of being practiced or of being carried out in various ways.

Presented herein are putter-type golf club heads comprising a plurality of striking surfaces capable of achieving consistent ball speeds across the striking surface to account for various ball impact locations. In many embodiments, the putter-type golf club head described herein includes a putter body comprising a dual-material striking surface having a first material and a second material. The first and second material varies in concentration away from the geometric center of the striking surface in a heel-to-toe direction to provide consistent ball speeds.

For example, in many embodiments, the proportion (or relationship) between the first material and the second material differs to account for where the ball could impact the striking surface (i.e. towards the toe portion, towards the heel portion, or towards the center portion). Altering the striking surface material relationship directly correlates to the impact efficiency or ball speed produced between the golf club head and the golf ball upon impact.

In many of the embodiments described herein, the golf club head is a putter-type golf club head.illustrates exemplary embodiments of putter-type golf club heads having a multi-material striking surface capable of controlling ball speeds across the striking surface, while accounting for impact feel and impact sound upon ball impact.

In many embodiments, the putter-type golf club head can have a loft angle less than 10 degrees. In many embodiments, the loft angle of the club head can be between 0 and 5 degrees, between 0 and 6 degrees, between 0 and 7 degrees, or between 0 and 8 degrees. For example, the loft angle of the club head can be less than 10 degrees, less than 9 degrees, less than 8 degrees, less than 7 degrees, less than 6 degrees, less than 5 degrees, less than 4 degrees, less than 3 degrees, or less than 2 degrees. For further example, the loft angle of the club head can be 0 degrees, 1 degree, 2 degrees, 3 degrees, 4 degrees, 5 degrees, 6 degrees, 7 degrees, 8 degrees, 9 degrees, or 10 degrees.

In many embodiments, the putter-type golf club head can have a weight that ranges between 320 and 385 grams. In other embodiments, the putter-type golf club head can range between 320 grams-325 grams, 325 grams-330 grams, 330 grams-335 grams, 335 grams-340 grams, 340 grams-345 grams, 345 grams-350 grams, 350 grams-355 grams, 355 grams-360 grams, 360 grams-365 grams, 365 grams-370 grams, 370 grams-375 grams, 375 grams-380 grams, or 380 grams-385 grams. In some embodiments, the weight of the putter-type golf club head can be 320 grams, 321 grams, 322 grams, 323 grams, 324 grams, 325 grams, 326 grams, 327 grams, 328 grams, 329 grams, 330 grams, 331 grams, 332 grams, 333 grams, 334 grams, 335 grams, 336 grams, 337 grams, 338 grams, 339 grams, 340 grams, 341 grams, 342 grams, 343 grams, 344 grams, 345 grams, 346 grams, 347 grams, 348 grams, 349 grams, 350 grams, 351 grams, 352 grams, 353 grams, 354 grams, 355 grams, 356 grams, 357 grams, 358 grams, 359 grams, 360 grams, 361 grams, 362 grams, 363 grams, 364 grams, 365 grams, 366 grams, 367 grams, 368 grams, 369 grams, 370 grams, 371 grams, 372 grams, 373 grams, 374 grams, 375 grams, 376 grams, 377 grams, 378 grams, 379 grams, 380 grams, 381 grams, 382 grams, 383 grams, 384 grams, or 385 grams.

The material of the putter-type golf club head can be constructed from any material used to construct a conventional club head. For example, the material of the putter-type golf club head can be constructed from any one or combination of the following: 8620 alloy steel, S25C steel, carbon steel, maraging steel, 17-4 stainless steel, 1380 stainless steel, 303 stainless steel, stainless steel alloys, or any metal or combination of metals for creating a golf club head. In other embodiments, the putter-type golf club heads can be constructed from non-metal materials such as a thermoplastic polyurethane material, a thermoplastic elastomer, and/or a thermoplastic composite material.

In many embodiments, the putter-type golf club head comprises a club head body (may also be referred to as “body” or “putter body”). The club head body comprises a toe portion, a heel portion, a top rail portion, a sole portion, a striking surface (or a portion of a striking surface), and a rear portion. The striking surface can provide a surface adapted for impact with a golf ball. The rear portion is rearwardly spaced from the striking surface. The sole portion is defined as being between the striking surface and the rear portion and resting on a ground plane (or playing surface) at an address position. The top rail can be formed opposite the sole portion. The striking surface is defined by the sole portion, the top rail portion, a heel portion and a toe portion, which is opposite the heel portion.

As mentioned above, in many embodiments, the putter-type golf club head can be configured to reside in the “address position”. Unless other described or stated, the putter-type golf club head is in an address position for all reference measurements, ratios, and/or descriptive parameters. The address position can be referred to as being in a state where (1) the sole portion of the putter-type golf club head rests on the ground plane which contacts and is parallel to a playing surface and/or ground plane and (2) the striking surface is substantially perpendicular to the ground plane and/or playing surface.

In many embodiments, the striking surface can be defined by at least the toe portion, the heel portion, the top rail portion, and the sole portion of the putter body. Further, as previously described, the striking surface can comprise of a multi-material striking surface. For example, the striking surface can include at least a first material and a second material that cooperate such that when a golf ball impacts the striking surface, the golf ball engages with two or more materials (i.e. a first material, a second material, etc.) having unique material characteristics to normalize ball speed across the club head while improving personal preference characteristics for a wide range of individuals (i.e. impact sound and/or impact feel).

In many embodiments, the first material can be softer, more flexible, and more deformable then the second material. In other embodiments, the second material can be harder, less flexible, and less deformable than the first material. In many embodiments, the second material can surround, border, or envelope the first material.

The first material of the striking surface can vary based upon the selection of the second material, as the second material comprises the majority of the striking surface. In many embodiments, the first material can be defined by a predetermined material characteristic (but not limited to) the hardness, the tensile strength, the flexure modulus, or the specific gravity of the material.

The hardness of the first material is generally softer than the hardness of the second material. In many embodiments, the hardness of the first material can have a Shore A value that varies between 30A and 95A. In some embodiments, the hardness of the first material can have a Shore A hardness value between 30A-40A, 40A-50A, 50A-60A, 70A-80A, 80A-90A, or 90A-95A. In alternative embodiments, the hardness of the first material can have a Shore A hardness value between 30A-35A, 35A-40A, 40A-45A, 45A-50A, 50A-55A, 55A-60A, 60A-65A, 65A-70A, 70A-75A, 75A-80A, 80A-85A, 85A-90A, or 90A-95A. In additional embodiments, the hardness of the first material can have a Shore A less than 95A, less than 90A, less than 85A, less than 80A, less than 75A, less than 70A, less than 65A, less than 60A, less than 55A, less than 50A, less than 45A, less than 40A, or less than 35A. In other embodiments, the hardness of the first material can have a Shore A hardness of 30A, 31A, 32A, 33A, 34A, 35A, 36A, 37A, 38A, 39A, 40A, 41A, 42A, 43A, 44A, 45A, 46A, 47A, 48A, 49A, 50A, 51A, 52A, 53A, 54A, 55A, 56A, 57A, 58A, 59A, 60A, 61A, 62A, 63A, 64A, 65A, 66A, 67A, 68A, 69A, 70A, 71A, 72A, 73A, 74A, 75A, 76A, 77A, 78A, 79A, 80A, 81A, 82A, 83A, 84A, 85A, 86A, 87A, 88A, 89A, 90A, 91A, 92A, 93A, 94A, or 95A.

The tensile strength of the first material is generally less than the tensile strength of the second material. The tensile strength of the first material can be between 0.5 MPa and 50 MPa. In many embodiments, the tensile strength of the first material can be between 0.5 MPa to 5.5 MPa, 5.5 MPa to 10.5 MPa, 10.5 MPa to 15.5 MPa, 15.5 MPa to 20.5 MPa, 20.5 MPa to 25.5 MPa, 25.5 MPa to 30.5 MPa, 30.5 MPa to 35.5 MPa, 35.5 MPa to 40 MPa, 40 MPa to 45.5 MPa, or 45.5 MPa to 50 MPa. In alternative embodiments, the tensile strength of the first material can be less than 50 MPa, less than 45 MPa, less than 40 MPa, less than 35 MPa, less than 30 MPa, less than 25 MPa, less than 20 MPa, less than 15 MPa, less than 10 MPa, or less than 5 MPa. In specific embodiments, the tensile strength of the first material can be approximately 0.5 MPa, approximately 5 MPa, approximately 10 MPa, approximately 15 MPa, approximately 20 MPa, approximately 25 MPa, approximately 30 MPa, approximately 35 MPa, approximately 40 MPa, approximately 45 MPa, or approximately 50 MPa.

The flexure modulus of the first material is generally lower than the flexure modulus of the second material. The flexure modulus of the first material can be between 0.5 MPa and 90 MPa. In many embodiments, the flexure modulus of the first material can be between 0.5 MPa and 5.5 MPa, 5.5 MPa and 10.5 MPa, 10.5 MPa to 15.5 MPa, 15.5 MPa to 20.5 MPa, 20.5 MPa to 25.5 MPa, 25.5 MPa to 30.5 MPa, 30.5 MPa to 35.5 MPa, 35.5 MPa to 40 MPa, 40 MPa to 45.5 MPa, 45.5 MPa to 50 MPa, 50 MPa to 55 MPa, 55 MPa to 60 MPa, 60 MPa to 65 MPa, 65 MPa to 70 MPa, 70 MPa to 75 MPa, 75 MPa to 80 MPa, 80 MPa to 85 MPa, or 85 MPa to 90 MPa. In alternative embodiments, the flexure modulus of the first material can be less than 90 MPa, less than 85 MPa, less than 80 MPa, less than 75 MPa, less than 70 MPa, less than 65 MPa, less than 60 MPa, less than 55 MPa, less than 50 MPa, less than 45 MPa, less than 40 MPa, less than 35 MPa, less than 30 MPa, less than 25 MPa, less than 20 MPa, less than 15 MPa, less than 10 MPa, or less than 5 MPa. In specific embodiments, the flexure modulus of the first material can be approximately 0.5 MPa, approximately 5 MPa, approximately 10 MPa, approximately 15 MPa, approximately 20 MPa, approximately 25 MPa, approximately 30 MPa, approximately 35 MPa, approximately 40 MPa, approximately 45 MPa, approximately 50 MPa, approximately 55 MPa, approximately 60 MPa, approximately 65 MPa, approximately 70 MPa, approximately 75 MPa, approximately 80 MPa, approximately 85 MPa, or approximately 90 MPa.

The specific gravity of the first material is generally lower (or can be the same) as the specific gravity of the second material. The specific gravity of the first material can be between 0.5 and 2. In many embodiments, the specific gravity of the first material can be between 0.5-0.75, 0.75-1, 1-1.25, 1.25-1.5, 1.5-1.75, or 1.75-2.0. In alternative embodiments, the specific gravity of the first material can be less than 2, less than 1.5, or less than 1.0.

The first material is generally comprised from a substantially non-metallic material and more preferably a polymeric material. For example, in many embodiments, the first material can be formed from an elastomer, a polyurethane, a thermoplastic elastomer, a thermoset elastomer, a thermoplastic polyurethane, a thermoset polyurethane, a viscoelastic material, a urethane, other polymers, other polymeric materials with doped metal portions, or combinations thereof. In many embodiments, the first material is selected from one of the categories listed above to satisfy one or more of the material characteristics listed above.

The second material of the striking surface can vary based upon the selection of the first material, as the first material provides certain ball impact characteristics. In many embodiments, the second material can be defined by a predetermined material characteristic (but not limited to) the hardness, tensile strength, flexure modulus, and specific gravity of the material.

The hardness of the second material is generally harder than the hardness of the first material. In many embodiments, the hardness of the second material can have a Shore D value that varies between 60D and 100D. In some embodiments, the hardness of the second material can have a Shore D hardness value between 60D-70D, 70D-80D, 80D-90D, or 90D-100D. In alternative embodiments, the hardness of the second material can have a Shore D hardness between 60D-65D, 65D-70D, 70D-75D, 75D-80D, 80D-85D, 85D-90D, 90D-95D, or 95D-100D. In additional embodiments, the hardness of the second material can have a Shore D hardness greater than 60D, greater than 65D, greater than 70D, greater than 75D, greater than 80D, greater than 85D, greater than 90D, greater than 95D, or greater than 100D. In other embodiments, the hardness of the second material can have a Shore D hardness of 60D, 61D, 62D, 63D, 64D, 65D, 66D, 67D, 68D, 69D, 70D, 71D, 72D, 73D, 74D, 75D, 76D, 77D, 78D, 79D, 80D, 81D, 82D, 83D, 84D, 85D, 86D, 87D, 88D, 89D, 90D, 91D, 92D, 93D, 94D, 95D, 96D, 97D, 98D, 99D, or 100D.

The tensile strength of the second material is generally greater than the tensile strength of the first material. The tensile strength of the second material can be between 40 MPa and 1040 MPa. In many embodiments, the tensile strength of the second material can be between 40 MPa to 140 MPa, 140 MPa to 240 MPa, 240 MPa to 340 MPa, 340 MPa to 440 MPa, 440 MPa to 540 MPa, 540 MPa to 640 MPa, 640 MPa to 740 MPa, 840 MPa to 940 MPa, or 940 MPa to 1040 MPa. In alternative embodiments, the tensile strength of the second material can be greater than 40 MPa, greater than 140 MPa, greater than 240 MPa, greater than 340 MPa, greater than 440 MPa, greater than 540 MPa, greater than 640 MPa, greater than 740 MPa, greater than 840 MPa, greater than 940 MPa, or greater than 1040 MPa. In specific embodiments, the tensile strength of the second material can be approximately 41 MPa, 42 MPa, 43 MPa, 44 MPa, 45 MPa, 46 MPa, 47 MPa, 48 MPa, 49 MPa, 50 MPa, 51 MPa, 52 MPa, 53 MPa, 54 MPa, 55 MPa, 56 MPa, 57 MPa, 58 MPa, 59 MPa, 60 MPa, 61 MPa, 62 MPa, 63 MPa, 64 MPa, 65 MPa, 66 MPa, 67 MPa, 68 MPa, 69 MPa, or 70 MPa. In alternative embodiments, the tensile strength of the second material can be 141 MPa, 241 MPa, 341 MPa, 441 MPa, 541 MPa, 641 MPa, 741 MPa, 841 MPa, or 941 MPa.

The flexure modulus of the second material is generally higher than the flexure modulus of the first material. The flexure modulus of the second material can be between 0.5 MPa and 300 MPa. In many embodiments, the flexure modulus of the second material can be between 0.5 MPa and 5.5 MPa, 5.5 MPa and 10.5 MPa, 10.5 MPa to 15.5 MPa, 15.5 MPa to 20.5 MPa, 20.5 MPa to 25.5 MPa, 25.5 MPa to 30.5 MPa, 30.5 MPa to 35.5 MPa, 35.5 MPa to 40 MPa, 40 MPa to 45.5 MPa, 45.5 MPa to 50 MPa, 50 MPa to 55 MPa, 55 MPa to 60 MPa, 60 MPa to 70 MPa, 70 MPa to 75 MPa, 75 MPa to 80 MPa, 80 MPa to 85 MPa, 85 MPa to 90 MPa, 90 MPa to 100 MPa, 100 MPa to 110 MPa, 110 MPa to 120 MPa, 120 MPa to 130 MPa, 130 MPa to 140 MPa, 140 MPa to 150 MPa, 150 MPa to 160 MPa, 160 MPa to 170 MPa, 170 MPa to 180 MPa, 180 MPa to 190 MPa, 190 MPa to 200 MPa, 200 MPa to 210 MPa, 210 MPa to 220 MPa, 220 MPa to 230 MPa, 240 MPa to 250 MPa, 250 MPa to 260 MPa, 260 MPa to 270 MPa, 270 MPa to 280 MPa, 280 MPa to 290 MPa, or 290 MPa to 300 MPa. In alternative embodiments, the flexure modulus of the second material can be less than 300 MPa, less than 275 MPa, less than 250 MPa, less than 225 MPa, less than 200 MPa, less than 175 MPa, less than 150 MPa, less than 125 MPa, less than 100 MPa, less than 75 MPa, less than 50 MPa, or less than 25 MPa. In specific embodiments, the flexural modulus of the second material be approximately 0.6 MPa, 5.6 MPa, 10.6 MPa, 15.6 MPa, 20.6 MPa, 25.6 MPa, 30.6 MPa, 35.6 MPa, 40.1 MPa, 45.6 MPa, 50.1 MPa, 55.1 MPa, 60.1 MPa, 70.1 MPa, 75.1 MPa, 80.1 MPa, 85.1 MPa, 90.1 MPa, 100.1 MPa, 110.1 MPa, 120.1 MPa, 130.1 MPa, 140.1 MPa, 150.1 MPa, 160.1 MPa, 170.1 MPa, 180.1 MPa, 190.1 MPa, 200.1 MPa, 210.1 MPa, 220.1 MPa, 230.1 MPa, 240.1 MPa, 250.1 MPa, 260.1 MPa, 270.1 MPa, 280.1 MPa, or 290.1 MPa.

The specific gravity of the second material is generally greater (or the same as) than the specific gravity of the first material. The specific gravity of the second material can be between 0.5 and 13.5. In many embodiments, the specific gravity of the second material can be between 0.5-1.5, 1.5-2.5, 2.5-3.5, 3.5-4.5, 4.5-5.5, 5.5-6.5, 6.5-7.5, 7.5-8.5, 8.5-9.5, 9.5-10.5, 10.5-11.5, 11.5-12.5, or 12.5-13.5. In alternative embodiments, the specific gravity of the second material can be approximately 0.5, approximately 1.0, approximately 1.5, approximately 2.5, approximately 3.5, approximately 4.5, approximately 5.5, approximately 6.5, approximately 7.5, approximately 8.5, approximately 9.5, approximately 10.5, approximately 11.5, approximately 12.5, or approximately 13.5

The second material can be generally comprised from a substantially non-metallic material or metallic material. For example, in many embodiments, the second material can be formed from a non-metallic material (i.e. an elastomer, a polyurethane, a thermoplastic elastomer, a thermoset elastomer, a thermoplastic polyurethane, a thermoset polyurethane, a viscoelastic material, a urethane, other polymers, other polymeric materials with doped metal portions, or combinations thereof). In alternative embodiments, the second material can be constructed from a metal material. For example, the second material can be constructed from any one or combination of the following: 8620 alloy steel, S25C steel, carbon steel, maraging steel, 17-4 stainless steel, 1380 stainless steel, 303 stainless steel, stainless steel alloys, tungsten, aluminum, aluminum alloys, ADC-12, titanium, or titanium alloys. In many embodiments, the second material is selected from one of the categories listed above to satisfy one or more of the material characteristics listed above.

In many embodiments, the second material can define a plurality of recesses or voids that resemble any shape. The characteristics (i.e. geometry, shape, dimensions, and spacing distance) of the recesses or voids formed by the second material can vary to achieved desired performance, aesthetics, and feel attributes. For example, in many embodiments, the second material can define a plurality of discrete voids or recesses that generally define a pill shape, a hexagonal shape, a split hexagonal shape, a circular shape, a rectangular shape, a triangular shape, a pentagonal shape, an octagonal shape, a curvilinear shape, a diamond shape, and/or a trapezoidal shape. In alternative embodiments, the second material, can form continuous voids or recesses that can generally be defined by one or more continuous curvilinear groove(s), one or more continuous arcuate groove(s), one or more continuous arc like grooves, one or more continuous linear groove(s), or one or more combinations thereof.

The first material can be configured to fill, partially fill, reside, occupy and/or be complimentary with one or more of the plurality of discrete recesses or voids defined by the second material. For example, in many embodiments, the first material can partially or entirely fill one or more of the plurality of voids or recess described above. In alternative embodiments, the first material can fill, partially fill, reside, and/or be complimentary with one or more of the continuous voids or recesses mentioned above. In embodiments, where the first material partially fills the plurality of recesses or voids, air can occupy the remaining unfilled portion.

The first and second materials can be configured to cooperate with each other to create different material characteristic regions. In many embodiments, the center region of the striking surface can be softer than adjacent heel and toe regions. In alternative embodiments, the center region of the striking surface can be more flexible than adjacent heel and toe regions. In other embodiments, the center region of the striking surface can be more deformable than adjacent heel and toe regions. Creating a center region that is more flexible, deformable, softer, and/or less responsive than adjacent heel and/or toe regions creates more uniform ball speed and sensory feedback characteristics (i.e. impact sound, impact feel, impact feedback, etc) across the striking surface.

Creating a center region that is less responsive than the corresponding heel and toe regions can be accomplished in many ways. For example, in embodiments, where a first soft material dominates a less soft second material, a less responsive center region is formed. In other embodiments, a less responsive center region can be formed by controlling the void and/or recess patterns to form larger first material land areas at the center region than at adjacent heel and toe regions.

illustrate an exemplary embodiment. More particularly,illustrate an example of a putter-type golf club headcomprising a dual-material striking surfacehaving a first materialand a second material. The putter-type golf club head comprises a putter bodyhaving a toe portion, a heel portionopposite the toe portion, a top rail portion, a sole portionopposite the top rail portion, a portion of a striking surface, and a rear portionopposite the striking surface portion.

Further,illustrate the striking surfaceof the putter bodyforming a plurality of continuous groove recesses. These continuous groove recessescan separate the striking surfaceinto second material land areas that form ball contact surfaces and continuous groove areas that form non-ball contact surfaces (upon golf ball impact). Through a combination of continuous recesses being entirely arcuate or having arcuate portions, the proportion of ball contact surfaces and non-ball contact surfaces can vary across the striking surface, yet create a consistent ball speed upon impact across the striking surface.

For example,illustrates a possible arrangement where the arcuate portions of each the continuous groove recessesare arranged to form a denser, more packed center region. This causes the center region to be less responsive to ball impacts than at areas (or regions) away from the center region (i.e. towards the heel or toe) as more continuous groove areas (non-ball contact surfaces) are present than ball contact surfaces. Additionally, to create a more densely packed center region towards the top rail and sole (at the center of the strike face), are entirely arcuate recesses (also referred to as semi-circle recesses) to increase the amount of continuous recesses (nonball contact surfaces). These semi-circle recesses are not present moving away from the center region and at the heel end and toe end. The arrangement can be progressive, or asymmetrically arranged from the center to the heel end and/or the center to toe end of the striking surface.

Moving away from the center region toward the heel or toe, the spacing distance between adjacent arcuate portions can gradually increase to introduce more ball contact surface. Increasing the amount of ball contact surfaces (in a heel-to-toe direction) creates a more responsive region when compared to the less responsive center region. As the response of the striking surface changes, this aids in creating a consistent ball speed across the striking surface.