Patent Application
20240009524
The present invention relates generally to a golf club head having a polymer supported striking face. More specifically, the golf club head in accordance with the present invention is further comprised of a striking face portion, an internal support layer, and an intermediary sandwiched layer juxtaposed between the striking face portion and the internal support layer.
Modern day golf club design has evolved since the early days of golf. The good news of all the technological advancements in golf club technology is that it makes the game of golf easier for golfers of all skill levels. However, all these advancements come with tremendous challenges for the golf club engineer.
One of the latest trends in golf club design is the utilization of multiple different materials in the same golf club head to take advantage of the individual performance characteristics the base material, and combining them to create a better performing golf club head. U.S. Pat. No. 5,316,298 to Hutin et al. discloses a club head with a front strike face with a vibration damper on the rear surface. The vibration damper includes a constraining layer connected to the rear surface through an interposed visco-elastic material.
U.S. Pat. No. 9,844,230 to Snyder shows an iron body and a ball striking plate engaged with the iron body. The ball striking plate may include a face layer and a backing layer of a polymeric material to isolate the face layer from the iron body.
It should be noted that although the utilization of multi-material golf club head has been around, the industry has always been perplexed by the utilization of multi-material around the striking face portion of the golf clubhead due to the high amount of stress when impacting a golf ball. The present invention focuses on a golf club head having a multi-layered, multi-material striking face of a golf club head to further improve the performance of a golf club head.
One aspect of the present invention is an iron type golf club comprising a golf club head, a grip and a shaft therebetween, wherein the golf club head comprises has improved COR and feel. The golf club head is preferably comprised of a striking face portion located at a frontal portion and an aft body portion attached to the striking face portion to form a cavity therebetween. The golf club head has a topline, a sole, a toe portion, a heel portion and a hosel. In the invention, the striking face portion preferably has a thickness of between 0.6 mm and 2.4 mm at the face center. The iron type golf club head is further comprised of an internal support layer located in the cavity that is coupled to the aft body portion and an intermediary sandwiched layer juxtaposed between the striking face portion and the internal support layer. The intermediary sandwiched layer is preferably comprised of a polymeric material having a sandwiched face layer hardness less than 75 Shore A and has a thickness of 1 mm and 10 mm at the face center. In an embodiment of the invention, the internal support layer only abuts between 25% and 75% of the intermediary sandwiched layer. Moreover, it is preferred that the intermediary sandwiched layer abuts significantly more of the striking face portion and preferably between 90% and 100% of the striking face portion. Most preferably, the internal support layer comprises a perimeter support portion circumscribing the cavity in the golf club head and has a width of between 2 mm and 20 mm and a thickness of between 0.5 mm and 5 mm. Thus, the intermediary sandwiched layer is supported by the perimeter portion, but a substantial portion is not supported by the internal support layer. In one embodiment, the perimeter support portion has a topline width WTL adjacent the topline that is between 2 mm and 5 mm and a sole width WS adjacent the sole that is between 6 mm and 20 mm. Preferably, the sole width WS is at least 1.5 times greater than the topline width WTL.
Another preferred embodiment of the present invention is an iron type golf club comprising a golf club head, a grip and a shaft therebetween, wherein the golf club head comprises has improved COR and feel. The golf club head is preferably comprised of a striking face portion located at a frontal portion and an aft body portion attached to the striking face portion to form a cavity therebetween. The golf club head has a topline, a sole, a toe portion, a heel portion and a hosel. In the invention, the striking face portion preferably has a thickness of between 0.6 mm and 2.4 mm at the face center. The iron type golf club head is further comprised of an internal support layer located in the cavity that is coupled to the aft body portion and an intermediary sandwiched layer juxtaposed between the striking face portion and the internal support layer. The intermediary sandwiched layer is preferably comprised of a polymeric material having a sandwiched face layer hardness less than 75 Shore A and has a thickness of 1 mm and 10 mm at the face center. The internal support layer only abuts between 25% and 75% of the intermediary sandwiched layer and is comprised of a perimeter support portion circumscribing the cavity in the golf club head and a horizontal support section extending from a heel section of the perimeter support portion to a toe section of the perimeter support portion. Preferably, the horizontal support section has a horizontal support width WH between 5 mm and 10 mm. Moreover, the horizontal support section can have a center portion that is closer to the striking face portion such that the intermediary sandwiched layer has a face center thickness that is between 80% and 40% of an intermediary sandwiched layer thickness closer to the topline, sole, toe portion or heel portion.
In an alternative embodiment of the present invention, the internal support layer only abuts between 25% and 75% of the intermediary sandwiched layer and is comprised of a perimeter support portion circumscribing the cavity in the golf club head and a vertical support section extending from a topline section of the perimeter support portion to a sole section of the perimeter support portion. Preferably, the vertical support section has a vertical support width WV between 8 mm and 15 mm. Moreover, the vertical support section can have a center portion that is closer to the striking face portion such that the intermediary sandwiched layer has a face center thickness that is between 80% and 40% of an intermediary sandwiched layer thickness closer to the topline, sole, toe portion or heel portion.
In a preferred embodiment, the internal support layer is comprised of steel and is integrally cast with the aft body portion. In another preferred embodiment the internal support layer is comprised of a thermoplastic material having a support tensile strength that is at least 10 times greater than a tensile strength of the intermediary sandwiched layer.
In a preferred embodiment of the present invention, the striking face portion of the golf club head is very thin and, more particularly, has a thickness of between 1.4 mm and 1.8 mm at the face center. Furthermore, it is preferred that the intermediary sandwiched layer has a thickness of 4 mm and 7 mm at the face center. Thus, the intermediary sandwiched layer has a thickness that is greater than twice as thick as the striking face portion thickness.
Yet another aspect of the present invention is an iron type golf club comprising a golf club head, a grip and a shaft therebetween, wherein the golf club head comprises has improved COR and feel. The iron type golf club comprises a golf club head, a grip and a shaft therebetween. Preferably, the head comprises a striking face portion located at a frontal portion of the golf club head and an aft body portion attached to the striking face portion forming a cavity therebetween, a topline, a sole, a toe portion, a heel portion and a hosel. Preferably, the striking face portion has a face center and a thickness of between 0.8 mm and 2.4 mm at the face center. Moreover, an internal support layer is coupled to the aft body portion such that it is located in the cavity and has a forward-facing front surface and an intermediary sandwiched layer is juxtaposed between the striking face portion and the internal support layer. Preferably, the intermediary sandwiched layer has a thickness of 1 mm and 10 mm at the face center and is comprised of a polymeric material having a sandwiched face layer tensile strength of between 4 MPa and 20 MPa. Preferably, the internal support layer comprises a thermoplastic material having a support layer tensile strength of between 60 MPa and 300 MPa and comprises a perimeter support portion circumscribing the cavity. Preferably, the perimeter support portion has a perimeter width of between 2 mm and 20 mm and a thickness of between 0.5 mm and 5 mm. Most preferably, the striking face portion has a back surface, and the intermediary sandwiched layer front surface abuts between 90% and 100% of the striking face portion back surface while the internal support layer only abuts between 25% and 75% of the intermediary sandwiched layer. In one embodiment, the internal support layer further comprises a horizontal support section extending from a heel section of the perimeter support portion to a toe section of the perimeter support portion. Preferably, the horizontal support section has a horizontal support width that is at least 10% greater than the perimeter width. In an alternate embodiment, the internal support layer further comprises a vertical support section extending from a topline section of the perimeter support portion to a sole section of the perimeter support portion.
The foregoing and other features and advantages of the invention will be apparent from the following description of the invention as illustrated in the accompanying drawings. The accompanying drawings, which are incorporated herein and form a part of the specification, further serve to explain the principles of the invention and to enable a person skilled in the pertinent art to make and use the invention.
The following detailed description describes the best currently contemplated modes of carrying out the invention. The description is not to be taken as limiting the invention and is provided for the sole purpose of illustrating the general principles of the invention. The scope of the invention is best defined by the appended claims. Various inventive features are described below, and each can be used independently of one another or in combination with other features.
The striking face portion 110 shown in
The external frontal face portion 124 is preferably formed of steel and located at an external frontal portion of the striking face portion 110. The external frontal face portion 124 has a substantially planar striking outer surface 132 that includes a plurality of grooves, not shown. More preferably, the external frontal face portion 124 is formed of a high strength steel having an Ultimate Tensile Strength of greater than 2000 MPa and more preferably greater than 2300 MPa. Most preferably, the external frontal face portion 124 is formed from AerMet 340 or the like. Moreover, it is preferred that the external frontal face portion 124 has a uniform thickness of about 0.6 mm to about 2.4 mm. Most preferably, the external frontal face portion 124 has a uniform thickness of about 1.4 mm to about 1.8 mm. This thin external frontal face portion 124 and its high strength assist in creating the high COR of the golf club head 100.
The internal face support 104 is formed in an internal hollow portion 129 of the golf club head 100. The internal face support 104 is preferably formed from steel having a tensile strength of about 400 MPa or greater and can be cast as a portion of the golf club head body portion 102 or formed of sheet metal, stamped or forged to shape and welded to the golf club head body 102. Preferably, the internal face support 104 has a thickness that is between about 0.5 mm and 5 mm, and more preferably, between about 0.8 mm and 2 mm.
The striking face portion 110 is abutted by the intermediary sandwiched layer 126, which is juxtaposed between the frontal face portion 124 and the internal face support 104. Preferably, intermediary sandwiched layer 126 is supported by the internal face support 104 around its perimeter, i.e., the intermediary sandwiched layer 126 is supported along the topline portion, the toe portion, the sole portion and the heel portion. This helps improve the overall striking face COR.
The intermediary sandwiched layer 126 is a polymeric material having a tensile strength within the range of about 4 MPa and 20 MPa and more preferably, 6 MPa and 12 MPa, when measured according to ASTM D412. The intermediary sandwiched layer 126 can be pre-formed and inserted into the cavity or can be injection molded into the cavity between the back surface of the frontal face portion 124 and the internal face support 104. The very low tensile strength allows the external frontal face portion to deflect during impact and assists in creating a striking face portion with a very high COR. Still further, to keep the striking face portion from being too heavy, the specific gravity of the polymer is preferably between about 0.95 and 1.2 and the polymer has a Shore A hardness of less than 75, and preferably between about 30 and 60. Preferably, the intermediary sandwiched layer 126 is comprised of a silicone material, and more preferably, a silicone rubber such as SH9151U sold by KCC Silicone Corporation. Furthermore, the intermediary sandwiched layer 126 preferably has a substantially uniform thickness of about 1 mm to 10 mm, and more preferably, between about 3 mm and 7 mm. The intermediary sandwiched layer 126 is also preferably at least twice as thick as the external frontal face portion thickness at the face center FC.
As stated above, the intermediary sandwiched layer 126 is supported by the internal face support perimeter support portion 106 near the topline portion 112, the toe portion 114, the sole portion 116, and the heel portion 118. The perimeter support portion 106 preferably has a width of between about 2 mm and 20 mm. More preferably, the perimeter support portion 106 has a first topline width WTL adjacent the topline portion 112 that is between about 2 mm and 5 mm and a second sole width WS that is adjacent the sole portion 116 that is between about 6 mm and 20 mm and is at least 1.5 times greater than the first width WTL. Moreover, the internal face support 104 has a hollow center portion 108 that doesn't support the intermediary sandwiched layer 126 and abuts between 25% and 75% of the intermediary sandwiched layer back surface while the intermediary sandwiched layer 126 covers between 90% and 100% of the back surface of the frontal face portion 124. Thus, the frontal face portion 124 is substantially dampened by the intermediary sandwiched layer 126, but 75% to 25% of the intermediary sandwiched layer 126 is unconstrained by the internal face support 104. Preferably, the center portion 108 circumscribes the face center FC projection to allow the face center FC of the external frontal face portion 124 to deflect at impact to improve the overall striking face COR.
As discussed above, the intermediary sandwiched layer 126 is supported by the internal face support 204 perimeter support portion 206 near the topline portion 212, the toe portion 214, the sole portion 216, and the heel portion 218. The intermediary sandwiched layer 126 is also supported by the vertical support portion 222 of the internal face support 204 behind the face center FC. The perimeter support portion 206 preferably has a width of between about 2 mm and 20 mm. More preferably, the perimeter support portion has a first topline width WTL adjacent the topline portion 212 that is between about 2 mm and 5 mm and a second sole width WS that is adjacent the sole portion 216 that is between about 6 mm and 20 mm and is at least 1.5 times greater than the first topline width WTL. Moreover, the internal face support 204 has hollow center portions 208a and 208b that don't support the intermediary sandwiched layer 126, and the internal face support 204 abuts between 25% and 75% of the back surface of the intermediary sandwiched layer 126 such that 75% to 25% of the intermediary sandwiched layer 126 is unconstrained. In this embodiment, the vertical support portion 222 has vertical support length LV and a vertical support width WV. The vertical support length LV is measured from the topline section of the perimeter support portion 206 to the sole section of the perimeter support portion 206. Preferably, the vertical support length LV is between about 15 mm and 30 mm and the vertical support width WV is between about 8 mm and 15 mm. Most preferably, the vertical support width WV is between about 30% and 70% of the vertical support length LV. In this manner, the COR of the striking face portion 110 at face center FC can be controlled to be similar to the COR at ½ inch from face center FC towards the toe and ½ inch from face center FC towards the heel.
As discussed above, the intermediary sandwiched layer 126 is supported by the internal face support 304 perimeter support portion 306 near the topline portion 312, the toe portion 314, the sole portion 316, and the heel portion 318. The intermediary sandwiched layer 126 is also supported by the horizontal support portion 322 of the internal face support 304 behind the face center FC. The perimeter support portion 306 preferably has a width of between about 2 mm and 20 mm. More preferably, the perimeter support portion has a first topline width WTL adjacent the topline portion 312 that is between about 2 mm and 5 mm and a second sole width WS that is adjacent the sole portion 316 that is between about 6 mm and 20 mm and is at least 1.5 times greater than the first topline width WTL. Moreover, the internal face support 304 has hollow center portions 308a and 308b that don't support the intermediary sandwiched layer 126, and the internal face support 304 abuts between 25% and 75% of the back surface of the intermediary sandwiched layer 126 such that 75% to 25% of the intermediary sandwiched layer 126 is unconstrained. In this embodiment, the horizontal support portion 322 has horizontal support length LH and a horizontal support width WH. The horizontal support length LH is measured from the heel portion of the perimeter support portion 306 to the toe portion of the perimeter support portion 306. Preferably, the horizontal support length LH is between about 40 mm and 80 mm and the horizontal support width WH is between about 5 mm and 10 mm. Most preferably, the horizontal support width WH is between about 5% and 25% of the horizontal support length LH. In this manner, the COR of the striking face portion 110 at face center FC can be controlled across the striking face portion 110 and a solid feel can be achieved.
The striking face portion 410 shown in
An intermediary sandwiched layer such as 426 shown in
The internal face support 404 is secured in an internal hollow portion 429 of the golf club head 400. The internal face support 404 is preferably formed from a thermoplastic material or thermoplastic composite having a tensile strength of about 60 MPa to 300 MPa and a flexural modulus of between about 2000 MPa and 8000 MPa. Preferably, the internal face support 404 has a thickness that is between about 0.5 mm and 5 mm, and more preferably, between about 0.8 mm and 2 mm.
As discussed above, the intermediary sandwiched layer 426 is a polymeric material having a tensile strength within the range of about 4 MPa and 20 MPa and more preferably, 6 MPa and 12 MPa, when measured according to ASTM D412. The very low tensile strength allows the external frontal face portion to deflect during impact and assists in creating a striking face portion with a very high COR. Still further, to keep the striking face portion from being too heavy, the specific gravity of the polymer is preferably between about 0.95 and 1.2 and the polymer has a Shore A hardness of less than 75, and preferably between about 30 and 60. Preferably, the intermediary sandwiched layer 426 is comprised of a silicone material, and more preferably, a silicone rubber such as SH9151U sold by KCC Silicone Corporation. Furthermore, the intermediary sandwiched layer 426 preferably has a substantially uniform thickness of about 1 mm to 10 mm, and more preferably, between about 3 mm and 7 mm. The intermediary sandwiched layer 426 is also preferably at least twice as thick as the external frontal face portion thickness at the face center FC.
As stated above, the perimeter support portion 406 preferably has a width of between about 2 mm and 20 mm. More preferably, the perimeter support portion has a first topline width WTL adjacent the topline portion 412 that is between about 2 mm and 5 mm and a second sole width WS that is adjacent the sole portion 416 that is between about 6 mm and 20 mm and is at least 1.5 times greater than the first width WTL. Moreover, the internal face support 404 has a hollow center portion 408 that doesn't support the intermediary sandwiched layer 426 and abuts between 25% and 75% of the intermediary sandwiched layer back surface while the intermediary sandwiched layer 426 covers between 90% and 100% of the back surface of the external frontal face portion 424. Thus, the external frontal face portion 424 is substantially dampened by the intermediary sandwiched layer 426, but 75% to 25% of the intermediary sandwiched layer 426 is unconstrained by the internal face support 404. In this embodiment, the vertical support portion 422 has vertical support length LV and a vertical support width WV. The vertical support length LV is measured from the topline section of the perimeter support portion 406 to the sole section of the perimeter support portion 406. Preferably, the vertical support length LV is between about 15 mm and 30 mm and the vertical support width WV is between about 8 mm and 15 mm. Most preferably, the vertical support width WV is between about 30% and 70% of the vertical support length LV. In this manner, the COR of the striking face portion 410 at face center FC can be controlled to be similar to the COR at ½ inch from face center FC towards the toe and ½ inch from face center FC towards the heel.
Again, the striking face portion 110 shown in
An intermediary sandwiched layer such as 126 shown in
The internal face support 504 is secured in an internal hollow portion of the golf club head. The internal face support 504 is preferably formed from a thermoplastic material or thermoplastic composite having a tensile strength of about 60 MPa to 300 MPa and a flexural modulus of between about 2000 MPa and 8000 MPa. Preferably, the internal face support 504 has a thickness that is between about 0.5 mm and 5 mm, and more preferably, between about 0.8 mm and 2 mm.
As discussed above, the intermediary sandwiched layer 126 is a polymeric material having a tensile strength within the range of about 4 MPa and 20 MPa and more preferably, 6 MPa and 12 MPa, when measured according to ASTM D412. The very low tensile strength allows the external frontal face portion to deflect during impact and assists in creating a striking face portion with a very high COR. Still further, to keep the striking face portion from being too heavy, the specific gravity of the polymer is preferably between about 0.95 and 1.2 and the polymer has a Shore A hardness of less than 75, and preferably between about 30 and 60. Preferably, the intermediary sandwiched layer 126 is comprised of a silicone material, and more preferably, a silicone rubber such as SH9151U sold by KCC Silicone Corporation. Furthermore, the intermediary sandwiched layer 126 preferably has a substantially uniform thickness of about 1 mm to 10 mm, and more preferably, between about 3 mm and 7 mm. The intermediary sandwiched layer 126 is also preferably at least twice as thick as the external frontal face portion thickness at the face center FC.
As stated above, the perimeter support portion 506 preferably has a width of between about 2 mm and 20 mm. More preferably, the perimeter support portion has a first topline width WTL adjacent the topline portion 512 that is between about 2 mm and 5 mm and a second sole width WS that is adjacent the sole portion 516 that is between about 6 mm and 20 mm and is at least 1.5 times greater than the first width WTL. Moreover, the internal face support 504 has a hollow center portion 508 that doesn't support the intermediary sandwiched layer 126 and abuts between 25% and 75% of the intermediary sandwiched layer back surface while the intermediary sandwiched layer 126 covers between 90% and 100% of the back surface of the external frontal face portion 124. Thus, the external frontal face portion 124 is substantially dampened by the intermediary sandwiched layer 126, but 75% to 25% of the intermediary sandwiched layer 126 is unconstrained by the internal face support 504. In this embodiment, the horizontal support portion 522 has horizontal support length LH and a horizontal support width WH. The horizontal support length LH is measured from the heel portion of the perimeter support portion 506 to the toe portion of the perimeter support portion 506. Preferably, the horizontal support length LH is between about 40 mm and 80 mm and the horizontal support width WH is between about 5 mm and 10 mm. Most preferably, the horizontal support width WH is between about 5% and 25% of the horizontal support length LH. In this manner, the COR of the striking face portion 110 at face center FC can be controlled across the striking face portion 110 and a solid feel can be achieved.
As discussed above, the intermediary sandwiched layer 126 is supported by the internal face support 604 perimeter support portion 606 near the topline portion 612, the toe portion 614, the sole portion 616, and the heel portion 618. The intermediary sandwiched layer 126 is also supported by the vertical support portion 622 of the internal face support 604 behind the face center FC. The perimeter support portion 606 preferably has a width of between about 2 mm and 20 mm. More preferably, the perimeter support portion has a first topline width WTL adjacent the topline portion 612 that is between about 2 mm and 5 mm and a second sole width WS that is adjacent the sole portion 616 that is between about 6 mm and 20 mm and is at least 1.5 times greater than the first topline width WTL. Moreover, the internal face support 604 has hollow center portions 608a and 608b that don't support the intermediary sandwiched layer 126, and the internal face support 604 abuts between 25% and 75% of the back surface of the intermediary sandwiched layer 126 such that 75% to 25% of the intermediary sandwiched layer 126 is unconstrained. In this embodiment, the vertical support portion 622 has vertical support length LVA, LVB, and LVC and a vertical support width WV. The vertical support length LVA, LVB, and LVC is measured from the topline section of the perimeter support portion 606 to the sole section of the perimeter support portion 606. Preferably, the vertical support length LVA, LVB, and LVC is between about 15 mm and 30 mm and the vertical support width WV is between about 8 mm and 15 mm. Most preferably, the vertical support width WV is between about 30% and 70% of the vertical support length LVA, LVB, and LVC. In this manner, the COR of the striking face portion 110 at face center FC can be controlled to be similar to the COR at ½ inch from face center FC towards the toe and ½ inch from face center FC towards the heel. In this embodiment, the vertical support portion 622 is further divided into three portions, the center vertical support portion 622a, the top vertical support portion 622b and the bottom vertical support portion 622c. Preferably, the center vertical support portion 622a is substantially closer to the striking face portion 110 such that the intermediary sandwiched layer 126 has a first thickness at the face center tFC that is less than second perimeter thickness surrounding the face center tr. As shown, the top vertical support portion 622b and the bottom vertical support portion 622c couple the center vertical portion 622 to the perimeter support portion 606 but are angled from the perimeter support portion 606 toward the striking face portion 110. In this manner, the first thickness at the face center tFC is between about 80% and 40% of the second perimeter thickness tP ½ inch from face center toward the toe portion 614 and heel portion 618. Preferably, the center vertical support portion 622a has a center vertical support length LVA, the top vertical support portion 622b has a top vertical support length LVB and the bottom vertical support portion 622c has a bottom vertical support length LVC. In the preferred embodiment, the center vertical support length LVA is at least 20% greater than both the top vertical support length LVB and the bottom vertical support length LVC. In this manner, the COR of the striking face portion 110 can be held more constant in the areas around the face center FC.
An intermediary sandwiched layer such as 726 shown in
As discussed above, the intermediary sandwiched layer 726 is a polymeric material having a tensile strength within the range of about 4 MPa and 20 MPa and more preferably, 6 MPa and 12 MPa, when measured according to ASTM D412. The very low tensile strength allows the external frontal face portion to deflect during impact and assists in creating a striking face portion with a very high COR. Still further, to keep the golf club head 700 from being too heavy, the specific gravity of the polymer is preferably between about 0.95 and 1.2 and the polymer has a Shore A hardness of less than 75, and preferably between about 30 and 60. Preferably, the intermediary sandwiched layer 726 is comprised of a silicone material, and more preferably, a silicone rubber such as SH9151U sold by KCC Silicone Corporation. Furthermore, the intermediary sandwiched layer 726 preferably has a substantially uniform thickness of about 1 mm to 10 mm, and more preferably, between about 3 mm and 7 mm. The intermediary sandwiched layer 726 is also preferably at least twice as thick as the striking face portion 710 thickness at the face center FC.
An intermediary sandwiched layer such as 726 shown in
Other than in the operating example, or unless otherwise expressly specified, all of the numerical ranges, amounts, values and percentages such as those for amounts of materials, moment of inertias, center of gravity locations, loft, draft angles, various performance ratios, and others in the aforementioned portions of the specification may be read as if prefaced by the word “about” even though the term “about” may not expressly appear in the value, amount, or range. Accordingly, unless indicated to the contrary, the numerical parameters set forth in the above specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the present invention. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.
Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements. Furthermore, when numerical ranges of varying scope are set forth herein, it is contemplated that any combination of these values inclusive of the recited values may be used.
It should be understood, of course, that the foregoing relates to exemplary embodiments of the present invention and that modifications may be made without departing from the spirit and scope of the invention as set forth in the following claims.
The present application is a continuation of co-pending U.S. patent application Ser. No. 17/692,576, filed on Mar. 11, 2022, and the entirety of which is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 17692576 | Mar 2022 | US |
| Child | 18475183 | US |
