TWI457160B - Golf ball having high initial velocity - Google Patents

Description

Golf ball with high initial speed Cross-references to related applications

This application is based on 35 USC § 119(e), entitled "Golf Ball Having High Initial Velocity", and U.S. Provisional Patent Application No. 61/375,775, filed on Aug. 20, 2010. Priority is hereby incorporated by reference.

field

The present invention is generally directed to a golf ball having a plurality of layers. The layers are designed to have a specific relationship between the recovery factor and compression to achieve a high initial velocity.

background

Making golf balls with most layers is standard in the industry. Individual designers in the industry will feel that certain characteristics are more important than others, and a golf ball will be designed to optimize certain characteristics. Individual designers will also feel that certain characteristics are more important or needed than others.

In many cases, the golfer wants the golf ball to provide the longer the better the kickoff. In addition to the golfer's control, the length of the tee shot is also controlled by a number of factors, such as the tee box and the relative height of the fairway, obstacles at or near the fairway, wind speed, and climate. The length of the tee shot is also controlled by the golfer's swing parameters, such as his or her club head speed, his or her health status, and the club he or she chooses for a particular kickoff. The length of the tee shot is also affected by the departure of the driver. The initial speed control.

In other situations, for example, when playing a short game, the golfer needs to have a good feel and a good spin/rotation golf ball when hitting the ball. The sensing of a golf ball is often controlled by the material from which one or more cover layers are made. The choice of the covering material can also be determined based on durability, rub resistance, and color.

Many golfers need a balance between the length of the ball track and the sensing of the ball. While some golfers only want one or the other, it is more likely that a golfer will want to balance one of these features.

Therefore, there is a need to develop a ball that includes a combination of good sensing and a feature of a maximum initial velocity. A golfer generally considers a combination of these features necessary when hitting the ball.

summary

In an embodiment, a golf ball is provided. The golf ball can have a center of the ball and a cover that surrounds the center of the ball. The cover comprises a highly neutralized polymer. The core may comprise a mildening material. The ball core can have a first recovery factor and the ball can have a second recovery factor. The difference between the first recovery factor and the second recovery coefficient is less than about 0.032.

In another embodiment, a golf ball is provided. The golf ball can have a center of the ball and a cover that surrounds the center of the ball. The center of the sphere can have a compression x. The recovery coefficient of the ball can be expressed by the formula 0.6511-0.024x ² + 0.1165x. The coefficient of recovery of the center of the sphere can be expressed by the formula 0.7951-0.0121x ² +0.416x. The recovery factor of any ball made according to this trend line can be capped to produce a qualified ball. The use of the tempered material as the cover allows a designer to produce a qualified ball that uses a high energy center.

A golf ball can be designed to have a special relationship between compression, recovery factor, and initial speed. The material of the core and the coefficient of restitution can be designed to produce an expected initial velocity above one ball and/or a rotation of a ball. The material of the sphere and the coefficient of restitution can be designed to produce a recovery factor that is different from the expected one of the sphere as a whole. In particular, for a given recovery factor, a ball made in accordance with the present invention will tend to have an initial velocity that is higher than expected. This means that a golfer can have sufficient initial speed to achieve a good tee shot distance while having greater rotatability due to the low recovery factor when hitting the short rod, particularly at the time of the semi-trick shot.

These benefits are obtained by including, in the center of the sphere, a high energy material such as a highly neutralized polymer, and a ball comprising, for example, a thermoplastic polyurethane and a buffering or cushioning material in the cover. A ball having a given high energy center can give a designer more coverage options to achieve the desired ball performance parameters.

Other systems, methods, features, and advantages of the present invention will be or become apparent to those skilled in the <RTIgt; All such additional systems, methods, features, and advantages are intended to be included within the scope of the invention and are intended to be within the scope of the invention and

Simple illustration

The invention will be better understood with reference to the following drawings and description. The components in the figures are not necessarily to scale, In addition, in the drawings, like reference characters refer to the

1 is a side view of a golf ball according to the present invention; FIG. 2 is a cross-sectional view of an embodiment of a ball according to the present invention; and FIG. 3 is a view of another embodiment of the ball according to the present invention. Cross-sectional view; Figure 4 is a cross-sectional view of another embodiment of the ball in accordance with the present invention; Figure 5 is a graph comparing the initial velocity of the ball when tested with a driver of the ball and the recovery factor of the ball; Figure 6 is a graph comparing the recovery coefficients and compression of the two spheres and their corresponding spheres; and Figure 7 is a graph showing various trend lines from the various spheres of Figures 5 and 6.

Detailed description

The present invention discloses a multilayer ball. Although the embodiments described herein are limited to golf balls, the invention is not so limited. The techniques described herein are applicable to any multi-layer article, particularly a projectile, ball, entertainment device, or component thereof.

1 is a side view of a ball 100 made in accordance with the techniques disclosed herein. FIG. 1 shows a general pit pattern applied to one of the outer surfaces 102 of the ball 100. While the dimple pattern on the ball 100 affects the flight path of the ball 100, the absence of a particular dimple pattern is important to the disclosed embodiment. A designer can be selected by any suitable dimple pattern to be applied to the ball 100.

Figure 2 is a cross-sectional view of a first embodiment of a ball 100 taken along line 2-2 of Figure 1. As shown in Fig. 2, a ball 200 can have two layers. The ball 200 can include a ball 204 and a cover 206 that surrounds the ball 204. Any of the embodiments of the golf ball described herein can be made according to any conventional technique, such as compression and ejection molding of the core, injection molding any outer layer, optionally with an adhesive to the majority of the golf ball. Stick together and apply or coat the ball, for example by spraying, painting, dipping, and pad printing.

The core 204 can be made of a high energy efficient material. A high energy efficiency material will hit the material in a highly elastic manner. In certain embodiments, the core 204 can be made primarily or entirely of a highly neutralized polymer. In certain embodiments, the highly neutralized polymer can be HPF 1000 or HPF 2000 available from E.I. DuPont de Nemours and Company. In certain embodiments, the core 204 can have a diameter of between about 38 and about 41 mm. In certain embodiments, the cover 206 can be made of a lower energy efficiency or mildening material. A lower energy efficient material will hit the material in a less elastic manner. In certain embodiments, the cover 206 can be made primarily or entirely of a thermoplastic urethane resin. In certain embodiments, the cover 206 can have a thickness of at least 2.1 mm.

In some embodiments, one or more additional outer layers may be included, but are not shown in FIG. 2 or any of the remaining figures. A top coat can be applied to the cover 206 in Figure 2. The top coat can be a coating that is coated to improve or adjust the appearance of the ball 200. For example, the top coat can be applied to change the color of the ball 200 or to change the gloss on the ball 200. In another embodiment, an additional coating may take the form of applying a logo or other print to the outer surface 202 of the ball 200. It will be appreciated by those of ordinary skill in the art that these outer coatings can be applied to any of the embodiments described herein and, therefore, such optional coatings will not be described in conjunction with the following examples. It should be noted that golf balls are typically coated. All of the tested balls described in this application have coatings, such as coatings and protective coatings. While such coatings may have some effect on the recovery factor of the sphere, it is generally believed that this effect is negligible for consideration of these embodiments. However, if the coatings are made thick enough or made of a very hard or very soft material, this effect will be apparent for design purposes in accordance with embodiments of the present invention.

Figure 3 is a cross-sectional view of a second embodiment of a ball 100 taken along line 2-2 of Figure 1. As shown in Fig. 3, a ball 300 can have three layers. The ball 300 can include a core 304, an inner cover 308 surrounding the core 304, and a cover 310 surrounding the inner cover 308.

The core 304 can be made of a high energy efficient material. A high energy efficiency material will hit the material in a highly elastic manner. In certain embodiments, the core 304 can be made primarily or entirely of a highly neutralized polymer. In certain embodiments, the highly neutralized polymer can be HPF 1000 or HPF 2000 available from E.I. DuPont de Nemours and Company. In certain embodiments, the core 304 can have a diameter of between about 38 mm and about 41 mm. In certain embodiments, any layer other than the (equal) cover layer can comprise a highly neutralized ionic polymer. In some embodiments, all of the layers other than the (equal) cover layer can be gathered into a size between about 38 mm and 41 mm. In some embodiments, all of the layers other than the (equal) cover layer may aggregate to approximately 38.6 mm.

In certain embodiments, inner cover 308 and outer cover 310 may be made of one or more lower energy efficient or milder materials. In certain embodiments, inner cover 308, outer cover 310, or both may be made primarily or entirely of a thermoplastic urethane resin or a thermoplastic polyurethane resin. In other embodiments, inner cover 308, outer cover 310, or both may be made primarily or entirely of an ionic polymeric resin. In certain embodiments, the ionic polymeric resin can be SURLYN® available from E. I. DuPont de Nemours and Company. In some embodiments, the combined thickness of inner cover layer 308 and outer cover layer 310 can be about 2.1 mm.

Figure 4 is a cross-sectional view of the ball 100 taken along line 2-2 of Figure 1. As shown in Fig. 4, a ball 400 can have four layers. A first layer 412 can be an inner core layer, and a second layer 414 can be an outer core layer and can surround the first layer 412. A third layer 416 can be an inner cover layer and can surround the second layer 414. A fourth layer 418 can be an outer cover layer and can surround the third layer 416. The first layer 412 or the inner core layer and the second layer 414 or outer core layer may be considered together and referred to as the center 420. The third layer 416 or the inner cover layer and the fourth layer 414 or the outer cover layer may be considered together and referred to as a cover 422.

The core 420 can be made of one or more high energy efficient materials, and the layers of the first layer 412 and the second layer 414 can be made of a high efficiency material of a different formulation. In certain embodiments, at least one of the cores 420 can be made primarily or entirely of a highly neutralized polymer. In certain embodiments, the highly neutralizing polymer can be HPF 1000 or HPF 2000 available from E. I. DuPont de Nemours and Company. The cover 422 can be made of a less efficient or slower material. In some embodiments, the third layer 416, the fourth layer 418, Or both may be made primarily or entirely of a thermoplastic urethane resin. In other embodiments, the third layer 416, the fourth layer 418, or both may be made primarily or entirely of an ionic polymeric resin. In certain embodiments, the ionic polymeric resin can be SURLYN® available from E. I. DuPont de Nemours and Company. In some embodiments, the combined thickness of the third layer (inner cover layer) 416 and the fourth layer (outer cover layer) 418 can be about 2.1 mm. In certain embodiments, any layer other than the (equal) cover layer can comprise a highly neutralized ionic polymer. In some embodiments, all of the layers other than the (equal) cover layer can be gathered into a size between about 38 mm and 41 mm. In some embodiments, all of the layers other than the (equal) cover layer may aggregate to approximately 38.6 mm.

In Figure 4, ball 400 has been illustrated and shown as having a plurality of layers. In some embodiments, another layer can be added. For example, in some embodiments, an outer shell layer can be added between the core 420 and the cover 422. In other embodiments, an intermediate cover layer can be interposed between the third layer (inner cover layer) 416 and the fourth layer (outer cover layer) 418. In other embodiments, an intermediate core layer can be inserted between the first layer (inner core layer) 412 and the second layer (outer core layer) 414.

It will also be appreciated by those of ordinary skill in the art that many similar modifications may be made to any embodiment of the embodiments, depending on the particular needs of the designer, without departing from the embodiments. For example, a four-layer ball may include an inner core layer, an intermediate core layer, an outer core layer, and a single cover layer. Similarly, a ball and four layers may include a single cover layer and an inner cover layer, an intermediate cover layer, and an outer cover layer. Those of ordinary skill in the art will also be aware of balls having other numbers of intermediate layers. Accordingly, the illustrated embodiments are exemplary in nature and are not intended to be limiting.

Referring now to Figure 5, there is shown a diagram illustrating the difference between the disclosed embodiment and the currently available ball on the market. These balls will be explained in more detail below. The value on the left y-axis is the initial velocity of the ball when tested with a tee shot. Each ball system is struck with a 9.5 loft Nike SQ kicking wood under the same conditions (head speed, angle of impact, etc.).

The initial speed is shown in the figure by the height of each strip on the bar graph. The initial speed as shown in the bar graph is displayed in inches per hour. The initial speed of 150 miles per hour is equal to approximately 220 inches per second. The initial speed of approximately 170 inches per hour is equal to approximately 250 inches per second.

The value on the right side of the figure indicates the coefficient of restitution of the ball as a whole. To measure the recovery factor of an object, the object is fired by an air cannon at an initial velocity of about 40 meters per second. A steel plate is positioned about 1.2 meters from the gun, and a speed monitoring device is disposed at a distance of about 0.6 to about 0.9 meters from the gun. The object is launched by the air cannon and passed through the speed monitoring device to determine an initial velocity. The object then strikes the steel plate and bounces back through the speed monitoring device to determine a return speed. The recovery factor is the ratio of the return speed to the initial speed. The recovery coefficients for each ball are shown by line 544 appearing on the graph.

The x-axis represents the ball being tested. Each tested ball was tested for initial speed and recovery factor. The first nine balls (numbers 1-9) are commercially available golf balls. Each of these golf balls has a spherical core made of a butadiene rubber compound having a diameter of about 40 mm. The exact formula of the ball is slightly different for each ball. The spherical core of each ball is made of a different additive or different size of butadiene rubber that produces different compression and recovery coefficients. It is generally believed that there is a correlation between the coefficient of restitution and the size of the center of the sphere, and there may be a strong correlation, such that small changes in the size of the sphere have a non-negligible effect on the coefficient of recovery. The cover of each ball is approximately 1.4mm thick and is primarily made up of SURLYN production.

On the other hand, the ball labeled 10 is a ball made in accordance with this embodiment. The ball labeled 10 was changed to have a core made mainly of highly neutralized polymer resin having a diameter of about 38 mm. The diameter of the center of the ball can be as large as about 41 mm. The cover of the ball is about 2.1 mm thick, but can be as thin as about 0.9 mm. If desired, a cover layer can be included to ensure that the ball meets the minimum USGA size specification of 42.67 mm (1.680 inch).

In comparing the relationship between the initial velocity and the recovery factor, it should be noted that for the balls 1-9 there is a substantial correlation between the recovery factor and the initial velocity. For example, for balls 1, 2, 4, and 5 with a recovery factor below 0.795, the initial velocity drops below about 150.2. For balls 3, 6, 7 and 8 with a recovery factor above 0.800, the initial velocity is above about 150.8. For a ball 9 with a recovery factor of approximately 0.800, the initial velocity is approximately 150.5. Thus, the figure shows a general correlation between the recovery factor and the initial velocity.

However, the graph shown in Figure 5 shows that the initial velocity of the ball 10 deviates from the expected initial velocity of a conventional ball having a recovery factor of 0.774. For the ball 10, the coefficient of restitution has a value of approximately 0.774. The initial velocity is not less than 150 miles per hour as predicted by conventional balls 1-9, and the initial velocity of the ball 10 is maintained at 150.8, which is almost the same as the initial velocity of a ball having a recovery coefficient that is much higher than the ball 10. high. Thus, by using the ball structure described above, the ball recovery factor can be maintained relatively low to achieve better sensing and rotation while the short rod is being struck while maintaining a suitably high initial speed to achieve a longer distance with a tee shot.

This is especially important for half-trick strikes. With a lower recovery factor ball, the golfer will tend to hit the ball harder, i.e., at a higher club head speed to achieve the same distance as a ball with a higher recovery factor. This harder hit (higher club head speed) gives the ball more rotation. Therefore, a golfer can have a lower recovery coefficient ball that has a good initial speed and a teeing distance when the short rod is hit but has a higher degree of rotation.

Another feature that can be compared between the existing ball and the ball of the present invention can be seen in Figure 6. Fig. 6 is a graph showing the relationship between the compression amount and the recovery coefficient of various balls and centers. The value on the x-axis represents the amount of compression of the core layer within the ball. The amount of compression is determined in a manner well known in the art. The spherical center and/or the ball is placed under an initial load of 10 kg. The measurement of the diameter of the ball, typically millimeters, is taken at one or more points, such as at the or the ball pole, the seam, or an arbitrary point. Record a single value or an average of the values. The second measurement of the diameter of the ball, which is increased to 130 kg and is also millimeters, is taken at the same point or at most the same point. Record a single value or an average of the values under the larger load. The difference in millimeters between the recorded values is the amount of compression.

The value on the y-axis represents the coefficient of restitution of each of the four objects under consideration. Line 650 represents the relationship between the compression and recovery coefficients of a core made of a butadiene rubber compound having a diameter of about 38 mm. This rubber ball trend line is expressed by the following formula

y=0.7531-0.0128x ² +0.055x Equation 1

Where x is the inner core compression and y is the corresponding recovery coefficient.

Line 660 represents the relationship between the compression and recovery coefficients of a ball including one of the cores shown in cover line 650. This line is expressed by

y=0.6794-0.0179x ² +0.0831x Equation 2

Where x is the compression of the sphere and y is the recovery factor of the sphere as a whole. The difference between the relative recovery coefficient of the center of the sphere and the recovery factor of the sphere is in the range between about 0.035 and about 0.037.

However, a comparison of the relative recovery coefficients of the sphere comprising one of the spheres made primarily or entirely of a highly neutralized polymer shows a difference. Line 670 represents the relationship between this compression and recovery factor at a core of approximately 38 mm in diameter and made primarily or entirely of a highly neutralized polymer. This line is expressed by

y=0.7951-0.0121x ² +0.0416x Equation 3

Where x is the compression of the center of the sphere and y is the corresponding recovery factor.

Line 680 represents the relationship between the compression and recovery coefficients of a ball including one of the cores shown in cover line 670. The cover is the same cover structure as the cover of the ball determined by line 650. This line is expressed by

y=0.6511-0.024x ² +0.1165x Equation 4

Where x is the compression of the sphere and y is the recovery factor of the sphere as a whole. The difference between the relative recovery coefficient of the center of the sphere and the recovery factor of the sphere is in the range between about 0.026 and about 0.031.

Thus, as clearly shown in Figure 6, for a given inner core compression, one of the balls having a rubber core will have a ball than a sphere having a HNP (highly neutralized polymer) A lower recovery factor. Furthermore, in order to maximize the effect of the retarding material, the difference between the coefficient of recovery of the sphere and the coefficient of recovery of the sphere should be at least 0.026, but can be significantly higher, such as 0.037, 0.05, 0.1 or even higher. The lower the coefficient of recovery of the ball, the more the ball will rotate, so a ball having a higher recovery coefficient difference of, for example, at least 0.037 or at least 0.05 may be required. Since the overall coefficient of recovery of the ball can still be within the highest performance range when a gentle and grading cover is provided, the relatively high recovery factor of the spherical core made in accordance with the present invention as described above can be used in selecting the covering material. Significantly flexible.

These benefits are more simply shown in Figure 7, where the rubber centerline trend line 762 shows a spherical core compression that is consistently lower than the HNP centerline trend line 760 for a given recovery factor. The HNP Ball Heart Trend Line 764 (a trend line with one complete sphere of a HNP center) is shown for reference.

Therefore, replacing the rubber core having one of the same specific recovery coefficients with one of the resin cores having a specific recovery coefficient makes the relative recovery coefficient of the sphere and the center of the sphere greatly different. This is especially true when the resin core recovery coefficient exceeds the recovery factor given by the rubber core trend line and wherein the ball has a recovery factor less than the recovery factor expressed by

y=-0.0103x+0.8419 Equation 5

Where y is the recovery factor and x is an inner spherical compression.

This can usually be achieved by at least one inner layer (non-cover layer) being neutralized by a height. Ionic polymer/polymer to achieve. The nature of the cover does not have to change between the butadiene rubber core and the highly neutralized polymer core. However, the difference in the coefficient of restitution between the center of the sphere and the sphere is at least about 0.004 less when using the height to neutralize the polymer core. This allows one of the balls having a higher recovery factor to be made of the same covering material.

Other limitations may need to be observed when following the above-mentioned coefficient of recovery trend line of highly neutralized polymer spheres and spheres made of highly neutralized polymer spheres. For example, a qualified ball will have a recovery factor that is lower than the trend expressed by Equation 5 or, more conservatively, as shown below.

y=-0.0103x+0.8299 Equation 6

Where y is the recovery factor and x is an inner spherical compression. Therefore, a designer would like to set an upper limit on the recovery coefficient of a ball following Equation 4 so that the recovery coefficient does not exceed the recovery coefficient expressed by Equation 6.

A ball made within the scope of the above disclosure is considered to have better properties. Such a ball is considered to have a higher initial velocity than expected. Such balls can also use a wider variety of covering materials, particularly those with lower cost. Such a ball can provide a golfer with a less expensive ball and the ball has a longer trajectory than the other balls.

Other configurations of the multilayer article may also enhance these benefits. For example, a golf ball may be applied in accordance with the present invention and in the United States under the name "Golf Ball Having Layers with Specified Moduli and Hardnesses" and applied for on August 20, 2010. The teachings of the articles described in the application Serial No. 12/860,785, the disclosure of which is incorporated herein by reference.

Although various embodiments of the invention have been described, the description is illustrative, and not restrictive, and those of ordinary skill in the art will understand that many embodiments and implementations are possible within the scope of the invention. the way. Therefore, the invention is not limited except in the scope of the appended claims and their equivalents. In addition, various modifications and changes can be made within the scope of the appended claims.

100. . . ball

102. . . The outer surface

200. . . ball

202. . . The outer surface

204. . . Heart

206. . . cover

300. . . ball

304. . . Heart

308. . . Inner cover

310. . . Outer cover

400. . . ball

412. . . level one

414. . . Second floor

416. . . the third floor

418. . . Fourth floor

420. . . Heart

422. . . cover

Figure 1 is a side view of a golf ball in accordance with the present invention;

Figure 2 is a cross-sectional view of one embodiment of a ball in accordance with the present invention;

Figure 3 is a cross-sectional view of another embodiment of a ball in accordance with the present invention;

Figure 4 is a cross-sectional view of another embodiment of a ball in accordance with the present invention;

Figure 5 is a graph comparing the initial velocity of a ball with a kick-off wood and the recovery factor of the ball;

Figure 6 is a comparison of the recovery coefficients and compression of the two spheres and their corresponding spheres; and

Figure 7 is a diagram showing various trend lines from the various spheres of Figures 5 and 6.

200. . . ball

204. . . Heart

206. . . cover

Claims (20)

A golf ball comprising: a spherical core comprising a highly neutralizing polymer and having a diameter between 38 mm and 41 mm; and a covering comprising a mildening material and the retarding material having Highly neutralizing the lower energy efficiency of the polymer, wherein the cover is radially disposed outside the core and surrounding the core; wherein the core has a first recovery coefficient and the ball has a second recovery factor And wherein the difference between the first recovery coefficient and the second recovery coefficient is greater than approximately 0.026. The golf ball of claim 1, wherein the first coefficient of restitution is greater than 0.78. The golf ball of claim 1, wherein the second coefficient of restitution is less than 0.79. The golf ball of claim 3, wherein the second coefficient of restitution is about 0.774. The golf ball of claim 1, wherein the core has at least two layers, at least one layer comprising a highly neutralized polymer, and wherein the cover has at least two layers, at least one layer comprising a thermoplastic polyurethane. A golf ball according to claim 1, wherein the golf ball has a higher initial speed than a rubber ball having a similar non-spherical layer. A golf ball comprising: a ball core having a diameter between 38 mm and 41 mm and having a compression amount "x"; and a covering surrounding the center of the ball; wherein the ball has a recovery coefficient of: 0.6511-0.024x ² +0.1165x; and wherein the recovery coefficient of the center of the sphere is represented by: 0.7951-0.0121x ² +0.0416x. The golf ball of claim 7, wherein the center of the sphere has a coefficient of restitution greater than 0.78. The golf ball of claim 7, wherein the ball has a coefficient of restitution of less than 0.79. The golf ball of claim 7, wherein the core has at least one layer comprising a highly neutralizing polymer. The golf ball of claim 7, wherein the covering has at least one layer comprising a thermoplastic polyurethane. The golf ball of claim 7, wherein the golf ball has a coefficient of restitution that is less than a recovery factor expressed by: -0.0103x + 0.8419. A golf ball comprising: a spherical core comprising one or more layers; a covering comprising one or more layers, wherein the covering is radially positioned outside the spherical core and surrounding the spherical center; wherein the spherical core Having a diameter of 38 mm to 41 mm; wherein at least one of the core layers comprises a highly neutralizing ionic polymer; and wherein the core has a coefficient of restitution greater than a rubber core trend line recovery coefficient, wherein the rubber The centerline trend line recovery coefficient is expressed by the following formula: y = 0.7531 - 0.0128 x ² + 0.055x, where "y" is the recovery coefficient and "x" is an inner core compression amount. A golf ball according to claim 13, wherein the golf ball has a higher initial velocity than a rubber ball having a similar non-spherical layer. The golf ball of claim 13, wherein the ball has a coefficient of restitution that is less than a coefficient of restitution expressed by the formula: y = -0.0103x + 0.8419. A golf ball according to claim 13 wherein the core comprises a highly neutralizing polymer. The golf ball of claim 16, wherein the covering comprises a thermoplastic polyurethane. A golf ball according to claim 13, wherein the center of the sphere is composed of two layers, wherein at least one of the two layers of the core is composed of a highly neutralized polymer. The golf ball of claim 13, wherein the cover is comprised of two layers, wherein at least one of the two layers of the cover is comprised of a thermoplastic polyurethane. The golf ball of claim 13, wherein the recovery coefficient of the ball is less than a recovery coefficient expressed by the formula: y=-0.0103x+0.8299.