Golf ball with rubber core
By using a rubber core composed of butadiene homopolymer rubber and auxiliary rubber in golf balls, and adjusting the rebound coefficient and contact time, the problem of excessively long flight distance of golf balls has been solved, achieving the flight distance requirements that meet the new competition rules.
Patent Information
- Application Number
- CN202410670367.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-28
- Publication Date
- 2025-11-28
AI Technical Summary
The high rebound coefficient of existing golf balls leads to increased flight distance, which violates the regulations of the new competition. Therefore, it is necessary to reduce the flight distance through material improvements.
The golf ball uses a rubber core, with the core layer composed of butadiene homopolymer rubber and auxiliary rubber. The auxiliary rubber is selected from styrene/butadiene rubber, nitrile rubber, butyl rubber, brominated butyl rubber and ethylene/propylene rubber. By adjusting the rubber composition and distribution, the rebound coefficient and contact time are reduced.
Under the conditions of complying with the new competition rules, the flight distance of the golf ball has been reduced, resulting in a shorter contact time and rebound coefficient, in line with the standards of the USGA and R&A.
Smart Images
Figure CN121016151A_ABST
Abstract
Description
Technical Field
[0001] This application relates to a golf ball, and more particularly to a golf ball with a rubber core. Background Technology
[0002] Golf has always been regarded as a leisure activity for Western gentlemen. In recent years, with the improvement of people's living standards and the importance attached to leisure life, more and more people from all walks of life and different age groups have come to love this sport, making golf a sport for all.
[0003] The properties of a golf ball itself affect its flight direction and distance after impact, and also determine its controllability. Excellent golf balls possess properties such as high initial velocity, excellent feel at impact, and high spin.
[0004] However, the coefficient of restitution (COR) of current golf balls is too high, leading to a gradual increase in the flight distance. To assess a player's ability, the total fairway length needs to be continuously increased, creating numerous difficulties.
[0005] Therefore, the United States Golf Association (USGA) and the Royal and Ancient Golf Club (R&A) in the UK have jointly decided to completely ban existing golf balls starting in 2028. Under the new regulations, a golf ball, when hit at a test speed of 125 mph, an angle of 11 degrees, and 2200 rpm, must not travel more than 317 yards.
[0006] Therefore, how to improve materials to provide golf balls that meet the new competition rules has become one of the important issues that this project aims to address. Summary of the Invention
[0007] The technical problem to be solved by this application is to provide a golf ball with a rubber core, which addresses the shortcomings of the prior art.
[0008] To address the aforementioned technical problems, one technical solution adopted by this invention is to provide a golf ball with a rubber core. The golf ball includes a core layer and a shell, with the shell covering the core layer. The core layer is made of a rubber material, including butadiene homopolymer rubber and auxiliary rubber. The butadiene homopolymer rubber content is between 10% and 95% by weight, based on 100% of the total weight of the rubber material. The auxiliary rubber is selected from the group consisting of styrene / butadiene rubber, nitrile rubber, butyl rubber, brominated butyl rubber, and ethylene / propylene rubber. According to the initial velocity test method TPX3007 (Rev. 2.1) jointly established by the Royal and Ancient Golf Rules Ltd. and the United States Golf Association, the contact time of the golf ball is between 300 and 600 microseconds.
[0009] Furthermore, when the golf ball is hit at a test speed of 115 mph, a striking angle of 12.5 degrees, and 2600 rpm, the golf ball travels less than 270 yards in the air.
[0010] Furthermore, based on the total weight of the rubber material as 100% by weight, the content of butadiene homopolymer rubber is 50% to 95% by weight.
[0011] Furthermore, the number average molecular weight of butadiene homopolymer rubber is from 50,000 g / mol to 2,000,000 g / mol.
[0012] Furthermore, the number average molecular weight of the auxiliary rubber is from 25,000 g / mol to 2,500,000 g / mol.
[0013] Furthermore, the auxiliary rubber is a desulfurized rubber.
[0014] Furthermore, the ratio of the contact time of the golf ball, measured according to the Royal and Ancient Rules of Golf, Inc. and the United States Golf Association standard TPX3007 (Rev. 2.1), to the rebound coefficient of the golf ball, measured according to the Royal and Ancient Rules of Golf, Inc. and the United States Golf Association standard TPX3009 (Rev. 2.0), is between 560.5 and 600.
[0015] Furthermore, butadiene homopolymer rubber and auxiliary rubber exist in the rubber material as a continuous phase.
[0016] Furthermore, the auxiliary rubber is dispersed in the form of a dispersed phase within the butadiene homopolymer rubber, which exists in the form of a continuous phase.
[0017] Furthermore, the core layer accounts for 50% to 98% of the volume of a golf ball.
[0018] One of the beneficial effects of the present invention is that the golf ball with a rubber core provided by the present invention can reduce the flight distance of the golf ball by reducing the contact time and rebound coefficient during impact through the technical solution that "the rubber material includes butadiene homopolymer rubber and auxiliary rubber" and "the auxiliary rubber is selected from the group consisting of styrene / butadiene rubber, nitrile rubber, butyl rubber, brominated butyl rubber and ethylene / propylene rubber".
[0019] To further understand the features and technical content of this application, please refer to the following detailed description and drawings. However, the drawings provided are for reference and illustration only and are not intended to limit this application. Attached Figure Description
[0020] Figure 1 This is a three-dimensional schematic diagram of the golf ball with a rubber core according to the present invention.
[0021] Figure 2 This is a cross-sectional schematic diagram of a golf ball with a rubber core according to the first embodiment of the present invention.
[0022] Figure 3 This is a cross-sectional schematic diagram of a golf ball with a rubber core according to the second embodiment of the present invention. Detailed Implementation
[0023] The following specific examples illustrate the embodiments of the "golf ball with a rubber core" disclosed in this invention. Those skilled in the art can understand the advantages and effects of this invention from the content disclosed in this specification. This invention can be implemented or applied through other different specific embodiments, and the details in this specification can also be modified and changed based on different viewpoints and applications without departing from the concept of this invention. Furthermore, the accompanying drawings of this invention are for simple illustrative purposes only and are not depictions of actual dimensions, as stated in advance. The following embodiments will further describe the relevant technical content of this invention in detail, but the disclosed content is not intended to limit the scope of protection of this invention. In addition, the term "or" used herein may, depending on the actual situation, include any combination of any one or more of the associated listed items.
[0024] This invention provides a golf ball that conforms to new regulations. By adjusting the core material of the golf ball, this invention alters the characteristics of the golf ball at the moment of impact, thereby reducing the flight distance of the golf ball.
[0025] The flight distance of a golf ball is positively correlated with its initial velocity after being hit. However, the flight distance is also affected by wind direction and terrain. Therefore, the instruction manual will first discuss the relationship between the core material of the golf ball and its rebound coefficient and contact time after impact. After the material selection is determined, the flight distance of the golf ball will be measured in a field test.
[0026] Further analysis reveals that the initial speed of a golf ball is affected by the test speed, striking angle, contact time, and the ball's rebound coefficient. Generally, the most intuitive way to reduce the initial speed of a golf ball is to reduce its rebound coefficient. However, the rebound coefficient of most commercially available materials is negatively correlated with contact time. When the rebound coefficient of a golf ball decreases, the contact time at impact increases, so this must also be considered.
[0027] This invention improves the material of the core layer of the ball, and finds that the rebound coefficient is generally positively correlated with the contact time. Furthermore, it can reduce the rebound coefficient of the golf ball while also reducing the contact time, thereby reducing the initial speed and flight distance of the golf ball after impact.
[0028] To quantify the characteristics of the golf ball of this invention, the golf ball of this invention travels less than 270 yards when struck at a test speed of 115 mph, a striking angle of 12.5 degrees, and 2600 rpm. Furthermore, according to the Initial Speed Test Protocol TPX3007 (Rev. 2.1) jointly established by the Royal and Ancient Golf Rules, Ltd. and the United States Golf Association, the contact time of the golf ball of this invention is less than 440 microseconds.
[0029] [First Embodiment]
[0030] Please refer to both together. Figure 1 and Figure 2 As shown, the golf ball G of the first embodiment of the present invention includes a core layer 1 and a shell 2, with the shell 2 completely covering the core layer 1. Based on the overall volume of the golf ball, the volume ratio of the core layer 1 in the golf ball is 50% to 98%, for example: 60%, 70%, 80%, or 90%.
[0031] The core layer 1 is mainly composed of a rubber material, which includes butadiene homopolymer rubber and auxiliary rubbers. The butadiene homopolymer rubber content ranges from 10% to 95% by weight, with the total weight of the rubber material as 100% by weight.
[0032] When the rubber material contains only butadiene homopolymer rubber, the contact time of the golf ball during impact is relatively long. This invention, by adding auxiliary rubber, can reduce the rebound coefficient and contact time of the golf ball, thus giving it the desired characteristics. In other words, the design concept of this invention is to reduce the rebound coefficient and contact time of the golf ball through the blending of different rubber components.
[0033] Specifically, the auxiliary rubber may be selected from the group consisting of styrene / butadiene rubber (SBR), nitrile rubber (NBR), butyl rubber (IIR), brominated butyl rubber (BIIR), and ethylene / propylene rubber (EPDM), but the present invention is not limited thereto.
[0034] The properties (e.g., molecular weight) of the butadiene homopolymer and the auxiliary rubber also affect the properties of the core layer 1. Experimental testing has shown that the most suitable number-average molecular weight for the butadiene homopolymer is 50,000 g / mol to 2,000,000 g / mol, and the most suitable number-average molecular weight for the auxiliary rubber is 25,000 g / mol to 2,500,000 g / mol, but the invention is not limited to these values.
[0035] In some embodiments, the number average molecular weight of the butadiene homopolymer rubber is 100,000 g / mol, 200,000 g / mol, 300,000 g / mol, 400,000 g / mol, 500,000 g / mol, 600,000 g / mol, 700,000 g / mol, 800,000 g / mol, 900,000 g / mol, 1,000,000 g / mol, 1,100,000 g / mol, 1,200,000 g / mol, 1,300,000 g / mol, 1,400,000 g / mol, 1,500,000 g / mol, 1,600,000 g / mol, 1,700,000 g / mol, 1,800,000 g / mol, or 1,900,000 g / mol.
[0036] In some embodiments, the number average molecular weight of the auxiliary rubber is 50,000 g / mol, 100,000 g / mol, 200,000 g / mol, 300,000 g / mol, 400,000 g / mol, 500,000 g / mol, 600,000 g / mol, 700,000 g / mol, 800,000 g / mol, 900,000 g / mol, 1,000,000 g / mol, 1,100,000 g / mol, or 1,200,000 g / mol. 0 g / mol, 1,300,000 g / mol, 1,400,000 g / mol, 1,500,000 g / mol, 1,600,000 g / mol, 1,700,000 g / mol, 1,800,000 g / mol, 1,900,000 g / mol, 2,000,000 g / mol, 2,100,000 g / mol, 2,200,000 g / mol, 2,300,000 g / mol, or 2,400,000 g / mol.
[0037] In some embodiments, butadiene homopolymer rubber and auxiliary rubber are uniformly mixed and exist as a continuous phase in the rubber material. In other embodiments, the auxiliary rubber may also be dispersed as a dispersed phase within the butadiene homopolymer rubber, which exists as a continuous phase. By adjusting the distribution of the rubber components in the core material, the contact time and impact characteristics of the golf ball at impact can also be adjusted.
[0038] To prevent delamination due to material incompatibility, which could cause golf balls to break upon impact, butadiene homopolymer rubber can be used as the main component of the rubber material to improve the structural stability of the golf ball. In other words, the content of butadiene homopolymer rubber can be controlled to be greater than the content of auxiliary rubbers.
[0039] With the total weight of the rubber material as 100% by weight, the content of butadiene homopolymer rubber is 50% to 95% by weight, for example: 55% by weight, 60% by weight, 65% by weight, 70% by weight, 75% by weight, 80% by weight, 85% by weight or 90% by weight.
[0040] Furthermore, the rubber material may further include recycled rubber (desulfurized rubber). Compared to synthetic rubber, recycled rubber has a lower resilience coefficient due to the desulfurization process, thus reducing the contact time of the golf ball during impact. Moreover, the addition of recycled rubber can save on the amount of rubber material used, thereby reducing costs.
[0041] In practical applications, the material used to form the core layer of the golf ball may further include crosslinking agents and fillers. Specific examples of crosslinking agents include zinc acrylate and magnesium acrylate. Fillers can be dispersed as a dispersed phase in the rubber material. Fillers can be materials with a low specific gravity, so that the amount of rubber material added can be slightly reduced after adding fillers, thereby achieving cost savings and adjusting the properties of the golf ball.
[0042] Specifically, the filler has a lower specific gravity than the rubber material. The filler can exist in the form of fibrous structures, round particles, angular particles, or sheet-like structures, but this invention is not limited thereto. The filler can be zinc oxide, barium sulfate, or other high-specific-gravity metal powders (e.g., tungsten powder), but this invention is not limited thereto.
[0043] The outer surface of the shell 2 has multiple regularly arranged circular recesses 20, which can serve as a wind tunnel. The recesses 20 allow the airflow to generate a turbulent boundary layer on the spherical surface, reducing the void area behind the sphere and thus reducing air resistance.
[0044] The material of the shell 2 can be an elastomer or a polymer. The elastomer can be thermoplastic polyurethane (TPU), thermosetting polyurethane elastomer (TSU), or thermoplastic polyester elastomer (TPEE). The polymer can be an ionomer (e.g., Surlyn resin) or an ethylene / methacrylic acid copolymer, but the invention is not limited thereto.
[0045] [Second Embodiment]
[0046] Please refer to both together. Figure 1 and Figure 3 As shown, the golf ball G of the second embodiment of the present invention includes a core layer 1, a middle film layer 3, and a shell 2, wherein the middle film layer 3 is disposed between the shell 2 and the core layer 1. The structure and materials of the core layer 1 and the shell 2 are similar to those of the first embodiment, and therefore will not be described again here.
[0047] The intermediate film layer 3 can be selectively fixed between the core layer 1 and the shell 2 via an adhesive layer. The material of the intermediate film layer 3 can be thermosetting polyurethane elastomer (TSU), polyether ester elastomer (TPEE), ion-crosslinked polymer (e.g., HPF series resins from Dow), or thermoplastic.
[0048] For example, the thickness of the middle film layer 3 can be from 0.5 mm to 5.0 mm, such as: 0.6 mm, 0.8 mm, 1.0 mm, 1.2 mm, 1.4 mm, 1.6 mm, 1.8 mm, 2.0 mm, 2.2 mm, 2.4 mm, 2.6 mm, 2.8 mm, 3.0 mm, 3.2 mm, 3.4 mm, 3.6 mm, 3.8 mm, 4.0 mm, 4.2 mm, 4.4 mm, 4.6 mm, or 4.8 mm.
[0049] To demonstrate that the golf ball of the present invention can have a shorter contact time upon impact, according to the structure shown in the first embodiment (e.g. Figure 2 Golf balls (as shown) were made into samples 1 to 7. All golf balls in samples 1 to 7 had a core layer covered with thermoplastic polyurethane as the shell, the difference being that different rubber materials were used to manufacture the core layer.
[0050] In Samples 1 and 2, the core layer material consists only of butadiene homopolymer rubber. The butadiene homopolymer rubber can be neodymium-based catalyst-catalyzed butadiene homopolymer rubber (NdBR) or cobalt-based catalyst-catalyzed butadiene homopolymer rubber (KBR). The number average molecular weight of the butadiene homopolymer rubber ranges from 50,000 g / mol to 2,000,000 g / mol. In Sample 1, zinc pentachlorothiophenol (ZnPCTP) is further added to the rubber material, which enhances the softness and elasticity of the golf ball's core layer.
[0051] In samples 3 to 5, the core layer was made of butadiene homopolymer rubber and an auxiliary rubber. The auxiliary rubber was styrene / butadiene rubber (SBR) with a number-average molecular weight of 25,000 g / mol to 2,500,000 g / mol.
[0052] In sample 6, the core layer material only includes auxiliary rubber (styrene / butadiene rubber (SBR)).
[0053] In sample 7, the core layer material includes butadiene homopolymer rubber and desulfurized rubber. The desulfurized rubber is derived from tires and its components include styrene-butadiene rubber, polybutadiene rubber, and natural rubber. The number average molecular weight of the desulfurized rubber ranges from 25,000 g / mol to 2,500,000 g / mol.
[0054] In Table 1, the compression hardness of golf balls in samples 1 to 7 was measured using a compression tester manufactured by Precision ADCs. The Shore C hardness of the golf balls was measured according to the ASTM-D2240 standard test method. In addition, the coefficient of restitution of the golf balls was measured using a rebound coefficient measuring instrument manufactured by Precision ADCs at average test speeds of 125 ft / s and 175 ft / s, respectively.
[0055] Table 2 shows the initial velocity and contact time of the golf balls in samples 1 through 7, measured according to the Initial Velocity Testing Protocol TPX3007 (Rev. 2.1) jointly established by the Royal and Ancient Golf Rules, Ltd. and the United States Golf Association. Additionally, the rebound coefficient of the golf balls in samples 1 through 7 was measured at an average test velocity of 143 ft / s, according to the standard TPX3007 (Rev. 2.1) jointly established by the Royal and Ancient Golf Rules, Ltd. and the United States Golf Association. The values listed in Table 2 are averages after 12 tests.
[0056] Table 1
[0057]
[0058]
[0059] Table 2
[0060]
[0061]
[0062] The results in Tables 1 and 2 show that when the core material includes butadiene homopolymer rubber and auxiliary rubber, the rebound coefficient and contact time of the golf ball decrease with increasing auxiliary rubber content. Furthermore, the rebound coefficient and contact time are generally positively correlated. Given the decrease in both rebound coefficient and contact time, it is foreseeable that the flight distance of the golf ball will also decrease.
[0063] Similar effects can be achieved when recycled desulfurized rubber is added. Compared to the sample without added desulfurized rubber, the golf ball in sample 7 had a lower rebound coefficient and contact time. Therefore, recycled desulfurized rubber can also be used to replace auxiliary rubber to reduce the flight distance of golf balls.
[0064] Furthermore, to differentiate it from commercially available materials where the springback coefficient is generally negatively correlated with contact time, Table 2 lists the ratio of contact time to springback coefficient, demonstrating that the selection of materials in this invention does indeed adjust the relationship between springback coefficient and contact time. The results in Table 2 show that the ratio of contact time (TPX3007 (Rev. 2.1)) to springback coefficient (TPX3009 (Rev. 2.0)) can be between 560.5 and 600.
[0065] After determining the material selection, golf balls from samples 1 to 7 were tested in the field to measure their flight distance. The tests were conducted at a fixed speed of 115 mph and a backspin of 2600 rpm, and the results are listed in Table 3.
[0066] Table 3
[0067]
[0068] As shown in Table 3, the flight distance of a golf ball gradually decreases with increasing auxiliary rubber content. Good results are also achieved when recycled desulfurized rubber is incorporated. Therefore, this invention can reduce the flight distance of golf balls by adding auxiliary rubber, thus complying with the regulations of the new competition rules.
[0069] Beneficial effects of the embodiments
[0070] One of the beneficial effects of the present invention is that the golf ball with a rubber core provided by the present invention can reduce the flight distance of the golf ball by reducing the contact time and elastic coefficient during impact through the technical solution that "the rubber material includes butadiene homopolymer rubber and auxiliary rubber" and "the auxiliary rubber is selected from the group consisting of styrene / butadiene rubber, nitrile rubber, butyl rubber, brominated butyl rubber and ethylene / propylene rubber".
[0071] The content disclosed above is only a preferred and feasible embodiment of this application, and is not intended to limit the scope of protection of the claims of this application. Therefore, all equivalent technical changes made based on the content of this application specification and drawings are included within the scope of protection of the claims of this application.
Claims
1. A golf ball, characterized in that, The golf ball includes: A core layer is formed of a rubber material comprising butadiene homopolymer rubber and auxiliary rubbers; wherein, based on 100% by weight of the total weight of the rubber material, the butadiene homopolymer rubber content is between 10% and 95% by weight, and the auxiliary rubbers are selected from the group consisting of styrene / butadiene rubber, nitrile rubber, butyl rubber, brominated butyl rubber, and ethylene / propylene rubber; and A shell that covers the core layer of the sphere; Specifically, according to the initial velocity test method TPX3007 (Rev.2.1) jointly established by the Royal and Ancient Golf Rules Ltd. and the United States Golf Association, the contact time of the golf ball is 300 microseconds to 600 microseconds.
2. The golf ball according to claim 1, characterized in that, The golf ball travels less than 270 yards when hit at a test speed of 115 mph, a striking angle of 12.5 degrees, and 2600 rpm.
3. The golf ball according to claim 1, characterized in that, The butadiene homopolymer rubber content is 50% to 95% by weight, with the total weight of the rubber material being 100% by weight.
4. The golf ball according to claim 1, characterized in that, The number average molecular weight of the butadiene homopolymer rubber is from 50,000 g / mol to 2,000,000 g / mol.
5. The golf ball according to claim 1, characterized in that, The number average molecular weight of the auxiliary rubber is from 25,000 g / mol to 2,500,000 g / mol.
6. The golf ball according to claim 1, characterized in that, The auxiliary rubber is a desulfurized rubber.
7. The golf ball according to claim 1, characterized in that, The contact time of the golf ball is measured according to standard TPX3007 (Rev. 2.1) jointly established by Royal and Ancient Golf Rules Ltd. and the United States Golf Association, and the rebound coefficient of the golf ball is measured according to standard TPX3009 (Rev. 2.0) jointly established by Royal and Ancient Golf Rules Ltd. and the United States Golf Association, with the ratio of the contact time to the rebound coefficient being 560.5 to 600.
8. The golf ball according to claim 1, characterized in that, The butadiene homopolymer rubber and the auxiliary rubber exist in the rubber material in the form of a continuous phase.
9. The golf ball according to claim 1, characterized in that, The auxiliary rubber is dispersed in the form of a dispersed phase in the butadiene homopolymer rubber, which exists in the form of a continuous phase.
10. The golf ball according to claim 1, characterized in that, The core layer accounts for 50% to 98% of the volume of the golf ball.