JP4188246B2 - Golf ball - Google Patents

Description

Detailed Description of the Invention

Cross-reference of related applications This application is a provisional application of US Provisional Patent Application No. 60 / 337,123 filed on Dec. 4, 2001, and US Provisional Patent Application No. 60 / 356,400, filed Feb. 11, 2002, 2002. Priority is claimed based on US Provisional Patent Application No. 60 / 422,198 filed on October 30, and US Provisional Patent Application No. 60 / 422,333 filed on October 30, 2002. .

TECHNICAL FIELD OF THE INVENTION The present invention relates to golf balls, and in particular to golf balls having a core defining at least one indentation along an outer surface and a cover having at least one hole extending through the layer to the core.

Technical Field of the Invention far, many one-piece, two-piece (solid elastic core or core with a molded cover), multi-layer (mantle or cover layer of a liquid or solid core and multiple) golf balls have been made. Different types of materials and manufacturing methods used to mold these ball cores, mantles, covers and the like have been used, which have greatly changed the performance of the entire ball.

  For certain applications, it is required to produce a golf ball with a very thin cover layer. Therefore, it would be beneficial to provide a technique for producing a relatively thin cover layer.

  In addition, pullable pins have been used to hold the core or core while molding the outer cover layer (or other layer) thereon. These pins are pulled out with a somewhat fluid cover or mantle still during the molding process, filling the voids by the pins.

  However, pullable pins sometimes cause centering difficulties when pulled and decorative issues in lands and dimples (ie pin flashes, pin marks, etc.), which in turn is suitable for use and sales of golf balls. Requires additional steps to produce Furthermore, as the viscosity of the mantle or cover material decreases, the withdrawal pin becomes difficult to move due to material build-up, and it is necessary to stop and periodically clean the mold. In addition, the pins also create a “cold weld” when the void is filled during the molding process. This is detrimental to durability as many hits are made later and cracks are generated from the filled pin voids.

  Accordingly, it would be desirable to provide a method for forming an outer cover or intermediate layer on a golf ball without using a pull pin.

SUMMARY OF THE INVENTION One aspect of the present invention provides a golf ball having a cover that can be manufactured more cost-effectively than conventional balls, has favorable operability, and eliminates the problems associated with conventional balls. That is.

  Furthermore, another aspect of the present invention is to provide a golf ball having desirable spin, elasticity and durability characteristics.

  It is a further aspect of the present invention to provide a golf ball having a cover with dimples thinner than a conventional cover layer.

  Another aspect of the present invention is to provide a golf ball having an outer cover layer having deep dimples extending to at least the next inner layer or core of the ball.

  In yet another aspect of the invention, the invention is directed to a golf ball having a core and a cover. The cover has at least one indentation on its outer surface. The cover has at least one hole that passes through the cover and reaches the core. The holes in the cover are aligned with the core depressions to form deep dimples.

  In a further aspect of the invention, the golf ball has a core and a cover layer provided around the core. The core defines a plurality of depressions along the outer surface of the core. The cover layer defines a plurality of holes through the cover layer and reaching the core. At least one of the holes in the cover overlaps at least one recess defined by the cover to form a deep dimple.

  Thus, the present invention has multiple compositions and elements and interrelated steps. Furthermore, the present invention is directed to the relationship between articles having features and characteristics and the exemplified elements described in detail below.

BRIEF DESCRIPTION OF THE DRAWINGS The following is a brief description of the drawings, which are presented to illustrate the invention and are not intended to identify the invention.
FIG. 1 shows a golf ball according to a preferred embodiment of the present invention, which has a core and a cover layer having a single dimple, and one or more dimples extend through the cover to the core below or into the core. ing.
FIG. 2 is an opposing cross-sectional view of the preferred embodiment golf ball shown in FIG.
FIG. 3 shows a golf ball according to another embodiment of the present invention, which has a core element and a cover element. The cover element includes an outer cover layer formed with an inner cover layer and dimples, and one or more outer cover layers are formed. The dimples extend to the inner cover layer or into the inner cover layer.
FIG. 4 is an opposing cross-sectional view of the preferred embodiment golf ball shown in FIG.
FIG. 5 is a partial detailed cross-sectional view of a golf ball having a core and cover of a preferred embodiment according to the present invention, showing a double radius dimple extending through the cover to the underlying core.
FIG. 6 is a cross-sectional view of a golf ball having a core and cover according to a preferred embodiment of the present invention, showing a double radius dimple extending through the cover layer to the outer surface of the core.
FIG. 7 is a partial cross-sectional detail view of a golf ball having a core, an inner cover layer, and an outer cover layer of a preferred embodiment of the present invention, the outer cover layer having double radius dimples extending to the inner cover layer. ing.
FIG. 8 is a partial cross-sectional detail view of a golf ball having a core, an inner cover layer, and an outer cover layer of a preferred embodiment of the present invention, with a double radius extending through the outer cover layer of the golf ball to the inner cover layer. Shows dimples.
FIG. 9 is a plan view of the golf ball of the preferred embodiment of the present invention having a first normal dimple with three deep dimples arranged in a triangular shape around the golf ball pole.
FIG. 10 is a plan view of the golf ball of the preferred embodiment of the present invention having a first normal dimple with four deep dimples in a diamond shape around the pole of the golf ball.
FIG. 11 shows a golf ball having a core, an inner cover, a mantle layer, and an outer cover layer according to a preferred embodiment of the present invention, and showing dimples extending from the outer cover layer to the mantle layer.
FIG. 12 is a plan view of a golf ball having dimples formed on two cover layers according to a preferred embodiment of the present invention, showing the dimples formed on the inner cover layer and the outer dimples formed on the outer cover layer. .
FIG. 13 is a graph showing the relationship between the position of several dimples on a golf ball according to the present invention and the acting force in a self-supporting cavity during molding.
FIG. 14 is a perspective view of a golf ball showing an area defined along the outer surface of the ball.
FIG. 15 is a schematic view of a preferred embodiment of the molding apparatus and golf ball core according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION The preferred embodiment relates to a golf ball which is improved to a golf ball having a particularly cover one or more layers around the core. The cover has deep dimples or holes extending through one or more, preferably a plurality of outer covers, to the lower layer and / or to the lower layer or further lower layers. The core may be a wound core, such as a liquid surrounding or hollow, metal, or solid, but a solid core is most preferred. The golf ball of the present invention may be of standard size or large size, but has a special combination of cover layer thickness and dimple shape. As described in detail herein, the present invention also relates to one or more “deep dimples”. These deep dimples have a greater depth than the other dimples of the ball. Such deep dimples extend through at least one layer to the underlying ball element or layer and / or into it.

  With respect to the dimple shape or geometric cross section, the present invention is based on the recognition of special preferred properties as described below. Typically, for circular dimples, the dimple diameter is used to characterize the size of the dimple rather than about the perimeter of the dimple. Typical dimple diameters range from about 0.050 inches to 0.150 inches. A typical preferred dimple diameter is about 0.150 inches. The deep dimples can be as large as these or as described in more detail here. As will be appreciated, the circumference of the dimple can be obtained by multiplying the diameter by π.

Typical dimple depths that have been used commercially to date have been about 0.002 inches to about 0.020 inches, or more depending on cover thickness and / or flight characteristics. A depth of about 0.010 inches is typical of normal dimples. These dimples are used for golf balls having a typical cover with a thickness of 0.030 to 0.100 inches.

  However, the depth of the deep dimples of the present invention described here is deeper than the depth of normal dimples. Preferably the deep dimple penetrates at least the outer cover layer of the ball. More preferably, the deep dimple is 0.002 inches deeper than the normal dimple depth.

  In this regard, traditional traditional balls typically have a dimple depth of about 0.010 inches less than the cover thickness, and the dimples extend to, or contact, the next layer. There is nothing. Therefore, there is a minimum cover thickness to provide the desired depth of dimples. The golf ball of the present invention can form dimples in one or more layers, and therefore each layer can be very thin (0.010 inches), so that the cover has a greater depth than the desired dimple depth. Does not require thickness.

  In particular, the depth of the dimple can be defined by at least two ways. The first approach stretches a string from one side of the dimple to the other and measures the maximum dimension from that string to the bottom of the dimple. This is referred to herein as “string depth”. Another approach is to extend a virtual line corresponding to the curved surface of the entire surface of the ball so that it is over the dimple to be measured. Next, the dimension from this imaginary line to the bottom of the bottom of the dimple is measured. This is referred to herein as “surface depth”. Unless otherwise stated, the latter way of determining the dimple depth is used here.

  As explained in more detail below, the deep dimples included in the present invention are particularly advantageous when forming particular layers or elements around the core or intermediate ball assembly. The depth (ie, surface depth) of the deep dimples described herein ranges from about 0.002 inches to about 0.140 inches, more preferably from about 0.002 inches to about 0.05 inches, most preferably Is about 0.005 inch to 0.040 inch. Preferably, the overall depth is 0.025 inches. The deep dimple depth here is deeper than the typical dimple depth and extends at least to the outermost region of the mantle or core. Alternatively, the deep dimples can reach the bottom of the mated set of dimples on the mantle or core. Usually given in terms of the surface depth from the outer surface of the product ball unless otherwise stated.

  The diameter of the deep dimples may not be similar, but is preferably the same as the other dimples on the ball and is about 0.025 inches to about 0.250 inches, more preferably about 0.050 inches to 0. .200 inches. A preferred diameter is about 0.150 inch.

  In a further embodiment, the present invention relates to a golf ball having a core and a cover layer, wherein the cover layer includes one or more deep dimples extending to or into the next inner layer or element. Giving dimples. The cover may be a single layer or a plurality of layers such as two layers, three layers, four layers, and five layers. If the cover is a multi-layer cover, the dimples extend at least into or into the first inner layer and can also penetrate to further inner layers, mantles, intermediate layers, and / or cores. If the cover is a single layer, the deep dimples can extend to the mantle layer or core, or even into the interior. The cover layer can be formed of any material used for cover materials including, but not limited to, ionomers, non-ionomers, and ionomer and non-ionomer composites.

  In another embodiment, the invention relates to a golf ball having a core, cover layer, wherein the cover layer provides dimples that extend to the outer surface of the core. Golf balls may have a thin barrier coating between the core and cover that selectively prevents moisture from entering the core. This barrier coating preferably has a thickness of at least 0.0001 inches. Preferably, this barrier layer is at least 0.003 inches. In a two-piece golf ball, it is desirable to provide a barrier coating between the core and the cover.

  In a further embodiment, the present invention relates to a golf ball having a plurality of dimples along an outer surface. According to the present invention, one or more of these dimples are preferably two or more, more preferably three or more dimples completely penetrating the cover of the ball and the underlying layers or elements of the ball. Deep dimples extending inward. For example, for a golf ball having a core and a cover layer provided around the core, deep dimples extend through the cover and into the core.

  Further, the core or mantle layer may be formed with dimples such that the dimples on the core or mantle layer supplement and receive “deep dimples” from the mold. If one or more layers, such as an intermediate layer, are provided between the core and the cover layer, the deep dimples preferably extend through the cover layer to one or more of those layers and / or to the interior. This deep dimple may further extend to the core. The deep dimples of the present invention may be spherical or non-spherical. Further, the deep dimple portion that extends to or into the next inner layer or element may be the same size or a different size as the outer portion of the dimple.

  Furthermore, the deep dimples of the present invention can also be used for finished processing (eg, deburring, painting, printing, etc.) of the molded ball. For example, deep dimples can be used to support or secure a molded ball for surface treatment and / or coating.

  1 and 2 show a preferred embodiment golf ball according to the present invention. In particular, FIGS. 1 and 2 show a golf ball 10 having a core 20 with a cover layer 30 around it. The cover layer 30 defines a plurality of dimples 40 along the surface 35. One or more dimples, preferably two or more dimples, extend into the core 20 below the cover layer 30. These dimples are referred to herein as deep dimples and are shown as dimples 42 in the figure.

  3 and 4 show another preferred embodiment golf ball 110 according to the present invention. The golf ball 110 has a core 120, an inner cover layer 150 provided thereon, and an outer cover layer 160 formed around the inner cover layer 150. Cover layers 160 and 150 define a plurality of dimples 140 along the outer surface of cover layer 160. One or more dimples per hemisphere, preferably 2 or more, more preferably 3 or more, extend completely through the outer cover layer 160 and at least partially into the inner cover layer 150. These dimples that penetrate the outer cover layer are again referred to herein as deep dimples and are shown as dimples 142 in the figure.

  FIG. 11 shows a partial cross section of a golf ball 810 defining a deep dimple 850 formed in an outer cover layer 820 disposed on a mantle layer (or inner cover) 830 provided on a core 840. The deep dimples 850 have a common curved surface. Alternatively, deep dimples or depressions may be defined by different curved surfaces or shapes depending on the region. This will be described in detail below.

  Deep dimples may be circular, non-circular, combinations thereof, or other shapes. They may be of the same or different shapes, such as large circular dimples with small elliptical dimples in circular dimples, or circular or other shaped dimples in larger dimples. The dimples need not be symmetrical. Forming deep dimples in multiple layers allows the dimple depth to be distributed across two or more layers. FIG. 12 shows dimples 940 formed on both the inner and outer cover layers. A dimple inner portion 946 is formed in the inner layer and a dimple outer portion 948 is formed in the outer cover layer. For two-piece balls, the dimples are formed in the core and a single cover layer as described above. Further, if necessary, the dimples are formed in a cover and / or core layer that is greater than two.

  In another preferred embodiment, a multi-layer golf ball is produced having one or more deep dimples that project into the ball through at least one layer, such as an outer cover layer. In a further preferred embodiment, the deep dimples protrude through at least two layers. At least two layers of dimples are formed in the same geometric coordinate system (ie, the centers of both dimples are at the same position, and thus the dimples are concentric with each other) and span the layers in which the dimples are formed. To form a golf ball having dimples. This allows for thinner layers with conventional dimples. The dimples in one or more layers can be varied in depth, diameter, semi-system, and alignment with the dimples in the outer layer. This also allows for dimples in the dimples, with at least one smaller dimple in the inner or mantle layer within the larger diameter dimple in the outer layer, as shown in FIGS.

  FIGS. 5-8 show double radius dimples, double region dimples, or intra-dimple dimples (these terms are used interchangeably herein).

  One advantage of the double radius dimple is that the deep portion of the double radius can be filled with a coating or other material. This provides an effective method for forming a desired dimple depth as compared to other dimple formation methods. The shape of the dimple may be any desired shape, and the shape of each dimple may be the same or different. The shape of the dimple and its area are given when viewed from the direction extending along the diameter of the golf ball. Each region of the double dimple can be of various different or identical shapes, such as a circle, ellipse, square, triangle, polygon.

  Preferably, the depth of the second or deepest portion of the double radius dimple can be expressed as a percentage of the total depth of the dimple. In particular, the portion or region of the dimple that extends to the outermost surface of the ball is referred to herein as the “major dimple”. Similarly, the dimple extending in the deepest part of the dimple is referred to herein as a “minor dimple”. Accordingly, the preferred depth of the major dimple is approximately 20% to 60% of the total depth of the dimple. The depth is measured from the string of the major dimple between the major and minor parts to the bottom of the minor dimple. Here, as will be explained in more detail, this depth is measured with respect to a string extending over the span of the dimple, so it is a “string depth”. Regarding the diameter, the preferred diameter of the minor dimple is 10% to 70% of the major dimple.

  FIG. 5 is a partial detail view of a golf ball according to a preferred embodiment of the present invention. The golf ball 210 of this preferred embodiment has a core 220 with a cover layer 230 thereon. The cover layer has at least one dimple 240 along its outer surface 235. As described in connection with FIGS. 1 and 2, the core has one or more (preferably two or more per hemisphere, more preferably three or more) dimples completely penetrating the cover layer and under the cover layer. It extends in.

FIG. 5 further shows a deep dimple having two different curved surfaces. Referring to FIG. 5, the first radius R ₁ defines the portion of the dimple from the outer surface 235 of the golf ball 210 to the point where the deep dimple extends to the layer below the cover layer. Curved dimples changes in this respect, has been determined a radius R _2.

Preferably, R ₁ is about 0.130 inches to about 0.190 inches, and most preferably R ₁ is about 0.140 inches to about 1.80 inches. In some embodiments, R ₁ is about 0.100 inches to about 1.000 inches, and most preferably about 0.200 inches to 0.800 inches.

R ₂ is preferably about 0.025 inches to about 0.075 inches, and most preferably R2 is about 0.050 inches to about 0.065 inches. In some embodiments, R ₂ is in the range of about 0.002 inches to 0.50 inches, most preferably about 0.010 inches to about 0.200 inches. The overall diameter, or span, of the dimple 240 is referred to as the “major chord diameter” and is denoted here as D ₁ . The diameter or span portions of dimples extending in a layer beneath the outer cover, usually referred to as "minor chord diameter", here represented by D _2.

D ₁ is preferably about 0.030 inches to about 0.250 inches, more preferably about 0.100 inches to about 0.186 inches, and most preferably D ₁ is about 0.140 inches to about 0.186 inches. 0.180 inch.

D ₂ is preferably about 0.020 inches to 0.160 inches, more preferably about 0.030 inches to about 0.080 inches, and most preferably D ₂ is about 0.040 inches to about 0.0. 060 inches.

Therefore, the overall depth of the deep dimple portion defined by R ₁ is shown here as H _1, the depth of the dimple portion defined by R ₂ is shown here with H ₂ in. H ₁ is preferably from about 0.005 inches to about 0.135 inches, more preferably from about 0.005 inches to about 0.025 inches, and even more preferably from about 0.010 inches to about 0.015 inches. and most preferably, _{H 1} is about 0.015 inches. In one embodiment, H _{1 is} quickly from 0.005 inches to 0.015 inches. H ₂ is preferably in the range of about 0.005 inches to about 0.135 inches, more preferably about 0.005 inches to about 0.050 inches. H ₂ is preferably in the range of about 0.005 inches to about 0.030 inches. In some embodiments, H ₂ is about 0.005 inches to about 0.015 inches.

Referring to FIG. 6, another preferred embodiment golf ball 310 is shown. In this version of the invention, the golf ball 310 has a core 320 and a cover layer 330 thereon. The cover layer 330 defines one deep dimple 340 along the outermost surface of the golf ball 310. As can be observed, dimple 340 is defined by two different curved surfaces, each defined by radii R ₂ and R ₁ as described with respect to FIG. The other parameters D ₁ , D ₂ , H ₁ , H ₂ are as described with respect to FIG. FIG. 6 shows an embodiment in which the dimple 340 extends to the core 320 and does not extend into the core. On the other hand, FIG. 5 is directed to a dimple shape in which the dimples extend considerably into the core.

FIG. 7 illustrates a preferred embodiment of a golf ball 410 having a core 420, a mantle or inner cover 450, and an outer cover layer 460. The outer cover layer 460 defines at least one deep dimple 440 along the outermost surface of the golf ball 410. Dimples 440 two distinct regions, i.e. defined by two curved surfaces, each is defined by a radius R ₂ and R ₁ sequentially. The other parameters D ₁ , D ₂ , H ₁ , H ₂ are as described for FIG. As seen in FIG. 7, the dimple 440 extends through the outer cover layer 460 and into the inner cover layer, ie, the mantle layer 450.

FIG. 8 shows another preferred embodiment golf ball 510 according to the present invention. Golf ball 510 has a core 520 with an inner cover layer, ie, mantle layer 550 and outer cover layer 560 thereon. At least one deep dimple 540 is defined around the ball 510, that is, on the outer peripheral surface. The dimple 540 is defined along the outer surface 535 of the golf ball 510. As described above, the dimple 540 has two different regions or curved surfaces defined by the radii R ₁ and R ₂ . The other parameters D ₁ , D ₂ , H ₁ , H ₂ are the same as those described for FIG. The variant shown in FIG. 8 discloses a dimple 540 that does not extend significantly into the mantle layer or inner cover layer 550. Instead, the dimple 540 extends to the region of the outermost peripheral surface of the mantle layer or the inner cover layer 550.

  In various double radius dimples, double region dimples, or dimples within the dimples described herein, the present invention includes filling either region, or both regions, with various materials. The filling material is preferably a material different from the cover material, but can include it. Preferably, the filler material includes one or more color agents.

  An important characteristic of the dimple shape is the volume ratio. This volume ratio is the sum of the volume below the string that traverses the top of the dimple is slowed by the total volume of the ball.

  This volume ratio is an important parameter for ball flight. A high volume ratio usually results in a low flying ball. A low volume ratio often results in a high flying ball. A preferred volume ratio is about 1%. However, the ball of the present invention may have a large or small volume ratio.

  The number and / or arrangement of dimples does not necessarily change the coverage, ie the surface area. A typical coverage of the golf ball of the present invention is about 60% to about 95%, preferably about 83.8%. In other embodiments, the preferred coverage is from about 84% to about 85%. These percentages are the percentage of the surface area of the ball occupied by dimples. It will be appreciated that the golf balls of the present invention exhibit a coverage that is greater or less than that value.

  For a shape using a dimple having two or more different curved surfaces, i.e., dimples within a dimple, the volume ratio has less influence than a deep dimple. If there are enough dimples in the dimple or deep dimples that affect the result, the aerodynamics of the golf ball is greatly affected.

  The number of preferred or optimal deep dimples per ball varies. The preferred number is that required to fix or center the core during molding without adversely affecting aerodynamics. However, the present invention includes a relatively large number of deep dimples. That is, most of the aim of the present invention is directed to the use of a small number of deep dimples per golf ball, ie 1 to 10, preferably 1 to 8, more preferably 1 to 6, The invention also includes the use of fairly large numbers from about 50 to 250. It will also be appreciated that in certain applications, it may be desirable to form substantially all of the golf ball dimples, for example about 50 to 500, as deep dimples.

  In general, when the dimples are deepened, the ball flies lower than those with shallow dimples. As the number of deep dimples increases, the ball exhibits low trajectory flight. Therefore, it is a preferred approach to reduce the number of deep dimples. However, in other applications, the present invention includes a ball having many deep dimples.

  Deep dimples can hold the core and mantle during molding. Normally, deep dimples extend from the mold into the core and touch the core. However, the core is restored to its original shape to some extent, and the dimple volume is smaller at the point of contact than otherwise. This will be described in detail below.

  The overall shape of the dimple including the deep dimple may be any shape. For example, hexagons, pentagons, triangles, ellipses, and circles are all suitable. Some shapes are preferred over others, but there is no limit on the number of shapes. Currently, circular dimples are preferred. As for the cross-sectional shape, the dimple can use any geometric shape. For example, the dimple may be defined by a constant curvature or a plurality of curvatures, or a double radius shape, an elliptical shape, or a water drop shaped region.

Cover layer The cover has at least one layer. In a multi-layer cover, the cover has at least two layers and can have as many layers as desired, such as 2, 3, 4, 5, 6. The two-piece cover has a first or inner layer ply (also referred to as a mantle layer) and a second or outer layer or ply.

  The inner layer can be an ionomer, an ionomer blend, a non-ionomer, a non-ionomer blend, or a blend of ionomer and non-ionomer. Also, the outer layer can be an ionomer, an ionomer blend, a non-ionomer, a non-ionomer blend, or a blend of ionomer and non-ionomer, and can be the same or different material as the inner cover layer. For multilayer covers with three or more layers, they can be ionomers, ionomer blends, non-ionomers, non-ionomer blends, or blends of ionomers and non-ionomers, the layers being the same or different materials It can be.

  In another preferred embodiment of the golf ball, the inner layer or single cover layer comprises a higher acid (ie, 16% by weight or more) ionomer resin, or a higher acid mixture. More preferably, the inner cover layer comprises a higher acid (i.e., 16 wt% or more) ionomer resin neutralized to varying degrees with two or more different metal cations. The purpose of the stearic acid metal salt or other metal fatty acid salt is to reduce the overall manufacturing cost of the final product golf ball.

  In a further embodiment, the inner layer or single cover layer comprises a lower acid (ie, up to 16% by weight acid) ionomer resin or a lower acid ionomer blend. Preferably, the inner layer or single layer consists of a mixture of lower acid (ie, up to 16% by weight acid) ionomer resin neutralized to varying degrees with two or more different metal cations. With respect to the higher acid inner cover implemented, the inner cover layer may or may not include a metal stearate (ie, zinc stearate) salt or other fatty acid metal salt.

  In golf balls with a multi-layer cover, hard layers and / or low driver spins have been found to substantially increase elasticity (ie, superior flight distance) over known multi-layer cover balls. The softer outer layer provides the desired feel and high spin rate while maintaining the desired elasticity. The softer outer layer allows for greater deformation of the cover during impact and increases the contact area between the club face and the cover, thereby imparting greater spin to the ball. As a result, the soft cover provides a feel and operational characteristics similar to balata while maintaining flight distance and durability. Accordingly, the entire combination of the inner layer and the outer layer provides excellent elasticity (excellent flight distance) and durability (ie damage resistance) characteristics while maintaining the operability of the ball in all situations.

  The combination of the hard inner layer and the soft outer layer provides an excellent overall coefficient of restitution (eg, excellent elasticity) due to the improved elasticity of the inner cover layer created by the inner cover layer. Although some improvement in elasticity is created by the outer cover layer, the outer cover layer usually provides a more desirable feel and spin, especially at high lofts and low swing speeds such as half wedge shots.

  In one preferred embodiment, the inner cover layer is harder than the outer cover layer, typically a 1.68 inch ball, in the range of 0.0005 to 0.15 inch, preferably 0.001 to 0.10 inch. With a 1.72 (or more) inch ball, it is sometimes slightly thicker. The core and inner cover layer (if available) cooperate to be inner, i.e. with a coefficient of restitution of 0.780 or higher, more preferably 0.790 or higher, from 1.48 for 1.68 inch balls. Form an inner or intermediate ball for a 1.66 inch diameter, 1.72 inch (or larger) ball with a diameter of 1.50 to 1.70 inch.

The inner cover layer preferably has a hardness of at least 60 Shore D (or at least 100 Shore C). The golf ball of the present invention is particularly advantageous when the inner layer has a Shore D hardness of 65 or more (Shore C100 or more). These measurements are typically made according to ASTM unless the measurement is on the ball itself and not on the plaque.
If the inner layer is too soft or too thin, the shore D measurement of the inner layer becomes difficult because the layer bursts during the measurement. For such situations, an alternative Shore C measurement is utilized. Furthermore, if the core (or inner layer) is harder than the layer being measured, this sometimes affects the measurement.

  Furthermore, if Shore C or Shore D is measured on the plaque of the material, it will result in a value different from that measured on the ball. Therefore, when referring to the measurement of Shore hardness, the measurement is performed on the ball, and special mention is made when measuring the plaque.

  The properties of the inner cover layer described above provide an inner ball with a PGA compression of 100 or less. When the inner ball has a PGA compression of 90 or less, excellent operability is provided.

  The composition of the inner layer of the examples described herein is E.E. I. Higher acid ionomers such as the trademark Surlyn (R) developed by Dupont de Nemours & Company and the trademarks Escor (R) or lotek (R) by Exxon Corporation may be included. Examples of compositions used as the inner layer herein are described in detail in US Pat. No. 5,688,869, incorporated herein by reference. Of course, the inner layer of the higher acid ionomer composition does not limit the composition defined in this patent in any way. Their composition is incorporated for illustration only.

  The higher acid ionomer suitably used to form the composition of the inner layer is a metal salt of a reaction product of an olefin having 2 to 8 carbon atoms and an unsaturated monocarboxylic acid having 3 to 8 carbon atoms ( Sodium, zinc, magnesium, and the like). Preferably, the ionomer resin is a copolymer of ethylene and acrylic acid or methacrylic acid. In some situations, an acrylic ester (eg, iso-, or n-butyl acrylate, etc.) comonomer can be included to produce a softer terpolymer. The carboxylic acid group of the copolymer is partially neutralized (eg, approximately 10-100%, preferably 30-70%) with metal ions. Each higher acid ionomer resin included in the composition of the inner cover layer of the present invention contains greater than 16% by weight carboxylic acid, preferably from about 17 to about 25% by weight carboxylic acid, more preferably from about 18.5 to 21.5%. Contains weight percent carboxylic acid.

  The higher acid resins available from Exxon under the designation Escor or lotek are somewhat similar to the higher acid ionomer resins available under the trademark Surlyn®. However, Escor® or lotek® ionomer resins are poly (ethylene acrylic acid) sodium, zinc, etc. salts, and Surlyn® resin is poly (ethylene-methacrylic acid) zinc, There are distinct differences in properties due to the sodium and magnesium salts. Also, for example, use of a commercially available resin modified with an ethylene / acrylic acid resin may be considered.

  Examples of higher acid-based ionomers suitable for use in the present invention include Surlyn 8220 (R) and 8240 (both known as the composition of Surlyn (R) AD-8422), Surlyn (R) 9220 ( Zinc cation), Surlyn (R) SEP-503-1 (zinc cation), and Surlyn (R) 503-2 (magnesium cation), but are not limited thereto. According to Du Pont, all these ionomers contain about 18.5 to 21.5% by weight methacrylic acid.

  Examples of higher acid acrylic acid based ionomer resins used in the present invention include Escor® or lotek such as Ex1001, 1002, 959, 960, 989, 990, 1003, 1004 and 994 manufactured by Exxon. (Registered trademark), but is not limited to this. In this regard, Escor® or lotek® 959 is an ethylene-acryl neutralized ethylene acrylic acid copolymer that is neutralized by sodium ions. According to Exxon, lotek® 959 and 960 are from about 19.0 to about 21.0% by weight with a group of acids neutralized with about 30 to about 70% sodium and zinc ions, respectively. Contains acrylic acid.

  In addition, as a result of the applicant's previous development of many higher acid ionomers that have been neutralized to varying degrees by metal cations such as manganese, lithium, potassium, calcium, and nickel cations, Several higher acid ionomers and / or higher acid ionomer mixtures are available for making golf ball covers in addition to sodium, zinc, and magnesium higher acid ionomers or ionomer mixtures. These added cationic neutralized higher acid ionomer mixtures have been found to produce an inner cover layer that exhibits excellent elasticity and hardness based on the interactions that occur during the processing steps. Accordingly, these metal cation neutralized higher acid ionomer resins are now substantially higher in C.I. than the commercially available lower acid ionomer inner cover composition. O. Can be mixed to produce R.

  In addition, in particular, several cationic neutralized higher acid ionomers have been used by the applicant of the present invention to use alpha-orphene and alpha, beta-unsaturated carboxylic acids with various ranges of different metal cations, Manufactured by neutralizing to various degrees. This discovery is the subject of US Pat. No. 5,688,869, incorporated herein by reference. Higher acid copolymers (ie copolymers containing more than 16% by weight acid, preferably 17 to 25% by weight, more preferably 20% by weight acid) to the desired range (eg 10% to 90%) It has been found that many metal cation neutralized higher acid ionomers can be obtained by reaction with a metal cation salt that can be ionized or neutralized.

  The copolymer base is made with more than 16% by weight of alpha, beta-unsaturated carboxylic acid and alpha-olefin. Optionally, a comonomer softener can be included in the copolymer. Usually, the alpha-olefin has 2 to 10 carbon atoms and is preferably ethylene, and the unsaturated carboxylic acid is a carboxylic acid having 3 to 8 carbon atoms. Examples of such acids include acrylic acid, methacrylic acid, ethacrylic acid, chloroacrylic acid, crotonic acid, maleic acid, fumaric acid, and itaconic acid, with acrylic acid being preferred.

  The softener comonomer that can be selectively included in the inner layer of the golf ball of the present invention comprises a vinyl ether having an acid group of 2 to 10 carbon atoms, an alkyl group containing 1 to 10 carbon atoms, and an alkyl group of 1 Can be selected from the group consisting of vinyl esters of aliphatic carboxylic acids which are alkyl acrylic acid or methacrylic acid containing from 10 to 10 carbon atoms. Suitable softener copolymers include vinyl acetate, methyl acrylic acid, methyl methacrylic acid, ethyl acrylic acid, ethyl methacrylic acid, butyl acrylic acid and the like.

Thus, many examples of suitable copolymers used to make the higher acid ionomers included in the present invention include higher acid examples of ethylene / acrylic acid copolymers, ethylene / methacrylic acid copolymers, ethylene / itaconic acid. Copolymers, ethylene / maleic acid copolymers, ethylene / methacrylic acid / vinyl acetate acid copolymers, ethylene / acrylic acid / vinyl alcohol copolymers and the like are included but are not limited thereto.
The copolymer substrate broadly comprises greater than 16% by weight unsaturated carboxylic acid, about 39 to 89% by weight ethylene and 0 to about 40% by weight softener copolymer. Preferably, the copolymer comprises about 20% by weight unsaturated carboxylic acid and about 80% by weight ethylene. Most preferably, the copolymer comprises about 20% by weight acrylic acid and the remaining ethylene.

  Accordingly, a preferred higher acid-based copolymer that meets the above criteria is a series of ethylene-acrylic copolymers designated as Primacor® commercially available from The Dow Chemical; Company, Midland, Michigan. The metal cation salt used in the present invention is a salt that provides a metal cation capable of neutralizing the carboxyl group of the higher acid copolymer in various ranges. These include lithium acetate, calcium, zinc, sodium, potassium, nickel, magnesium, and manganese oxide acetate or hydroxide acetate salts.

  Such lithium ion sources include lithium hydroxide monohydrate, lithium hydroxide, lithium oxide, and lithium acetate. Calcium ion sources include calcium hydroxide, calcium acetate, and calcium oxide. Suitable zinc ion sources include zinc dioxide acetate, zinc acetate, and a mixture of zinc oxide and acetic acid. Examples of sodium ion sources are sodium hydroxide and sodium acetate. Potassium ion sources include potassium hydroxide and potassium acetate. Suitable nickel ion sources include nickel acetate, nickel oxide, nickel hydroxide. Magnesium sources include magnesium oxide, magnesium hydroxide, and magnesium acetate. Manganese sources include magnesium acetate and magnesium oxide.

  Metal ion neutralized higher acid ionomers ”are higher acid based copolymers and various metal cation salts of the copolymers, such as from about 200 ° F. to about 500 ° F., preferably from about 250 ° F. to about 350 ° F. Produced by reacting under high shear conditions of about 10 psi to 10,000 psi above the crystallization melting point. Other well known blending techniques can also be used. The amount of metal cation salt used to produce this new metal cation neutralized higher acid-based ionomer is sufficient to neutralize the desired proportion of the carboxylic acid group of the higher acid copolymer. is there. The neutralization range is usually 10% to 90%.

  Many different types of metal cation neutralized higher acid ionomers are produced by the process described above. These include higher acid ionomers neutralized to various ranges with magnesium, lithium, potassium, calcium, and nickel cations. In addition, higher acid ethylene / acrylic acid copolymers are used as the base copolymer component of the present invention, which is then neutralized by cations such as sodium, potassium, lithium, zinc, magnesium, manganese, calcium, and nickel. When the acrylic acid-based higher acid ionomer is neutralized to various ranges using a metal cation salt that generates acrylic acid, various cationic neutralized acrylic acid-based higher acid ionomer resins are produced.

  Compared to similar lower acid basis cation neutralized ionomer resins, metal cation neutralized higher acid ionomer resins exhibit superior hardness and elastic properties. These are properties that are particularly desired in the field of many thermoplastic resins, including the production of golf balls.

  Lower acid ionomers suitable for forming the composition of the inner layer of the inventive subject matter are reactive organisms of olefins having 2 to 8 carbon atoms and unsaturated monocarboxylic acids having 3 to 8 carbon atoms. Metal (sodium, zinc, magnesium, etc.) salts. Preferably, the ionomer resin is a copolymer of ethylene and acrylic or methacrylic acid. In some situations, additional comonomers such as acrylate esters (eg, iso- or n-butyl acrylate, etc.) can be included to produce a softer terpolymer. The carboxylic acid group of the copolymer is partially neutralized by metal ions (eg, about 10 to 100%, preferably 30 to 70%). Each lower acid ionomer resin contained in the inner cover layer component of the present invention contains 16% by weight or less of carboxylic acid.

  The components of the inner layer include E.I. I. Produced and sold by DuPont de Nemours & Company The trademark Surlyn (registered trademark), Escor (registered trademark), or Exxon Corporation under the name of Lotek (registered trademark), manufactured and sold by the low-acid ionomer originally manufactured Or as a blend of them.

  In one embodiment of the inner cover layer, a mixture of higher and lower acid ionomer resins is used. These may be a combination of the above-mentioned ionomers, preferably higher acid and lower acid ionomer resins in a weight proportion of 10 to 90%, 90 to 10%.

  Another embodiment of the inner layer comprises a non-ionomer thermoplastic resin or a thermosetting resin material. Preferred non-ionomer resin materials include, but are not limited to, metallocene catalyzed polyolefins or polyamides, polyamide / ionomer blends, polyphenylene ether / ionomer blends, and the like, which have a Shore D hardness of at least 60 (ie, m Shore C hardness). At least 90) with a flex modulus greater than about 30,000 psi, preferably greater than about 50,000 psi, which have other hardness and flexural factors that can be compared to the properties of the ionomer described above. Other suitable materials include, but are not limited to, thermoplastic or thermoset polyurethanes, thermoplastic block polyesters, such as polyester elastomers as marketed by DuPont under the trademark Hytrel®, or, for example, , EIf Atochem S .; A. Thermoplastic block polyamides, such as those on the market more under the trademark Pebax®, mixtures of these two or more non-ionomer thermoplastic elastomers, one or more ionomers and one or more non-ionomer thermoplastics Contains a mixture of elastomers. These materials can be blended with the above-mentioned ionomers to reduce costs compared to using good quality specific ionomers. Hytrel (R) and Pebax (R) are sometimes more expensive than certain ionomers, but these materials are typically more dense than ionomers and have different elastic properties at low impact Can therefore be desirable.

  Other suitable materials used for the inner cover layer or single cover layer of the present invention include polyurethane. These are described in detail below.

  Any number of inner layers can be used. Each layer may be the same or different material as the other layers, and each may have the same or different thickness. If possible, the inner layer or layers may be the same as the outer layer.

  A core having a hard inner layer thereon typically provides a multi-layer golf ball with elasticity and flight distance. In one preferred embodiment, the outer cover layer is relatively softer than the inner cover layer. For a golf ball having a core and a single cover layer, the cover layer can be a soft cover, as described herein. This softness gives the feel and operability that balata or balata blend balls usually have.

  The soft outer cover layer or ply is a relatively soft, low bending modulus (about 500 psi to about 50,000 psi, preferably about 1,000 psi to about 25,000 psi, more preferably 5,000 psi to 20,000 psi) material Or formed of a mixture. The outer cover layer (or single cover layer if possible) consists of ionomer, non-ionomer, ionomer mixture, non-ionomer mixture, ionomer and non-ionomer mixture. Preferably, the outer cover layer comprises polyurethane, polyurea), a mixture of two or more polyurethane / polyurea, preferably a thermoplastic polyurethane, or a polyurethane / polyurea to be molded (described in detail below). Consists of.

  The outer layer is 0.0005 to about 0.15 inches thick, preferably about 0.001 to about 0.10 inches thick, sometimes a little thicker for 1.72 inch balls, but at a lower cost. The thickness is required to obtain a desired operability. The thickness is determined as the average thickness of the cover layer without dimples. The outer cover layer is preferably 60 or less in Shore D hardness (or 90 or less in Shore C hardness), and more preferably 55 or less in Shore D hardness (or 80 or less in Shore C hardness).

  In other preferred embodiments, the outer cover layer is relatively harder than the inner cover layer. The outer cover layer is made of a relatively hard material with a high bending modulus (about 40,000 psi or higher) or a mixture thereof. The inner cover layer can be a softer material such as polyurethane or other non-ionomer, or mixtures thereof, and the outer cover layer can be a hard material such as hard ionomers, non-ionomers, or mixtures thereof. Can do.

  Further, in an alternative embodiment, both the inner and / or outer cover layers (if possible, a single cover layer) can be further non-ionomer thermoplastic or thermoset with a soft, low bend factor of 100 wt%. It is possible to further include a functional resin. The non-ionomer material is suitable as long as it provides operability and durability without adversely affecting the properties of the cover layer. These include, but are not limited to, functionalized styrene-butadiene-styrene block copolymers, styrene-ethylene-butadiene-styrene (SEBC) block copolymers, such as Shell ChemCo, Kraton®, and functionalized. SEBS block copolymer; metallocene-catalyzed polyolefin, ionomer / rubber blends such as Spalding US Pat. Nos. 4,986,545 and 5,187,013, and Hytrel® polyester elastomer from Dupont, EIF Atochem S. A. A styrene-butadiene-styrene block copolymer comprising Pebax® from

  The outer cover layer of the present invention is formed on the core (and inner cover layer or multilayer cover layer) and has a coefficient of restitution of at least 0.777, more preferably at least 0.780, and most preferably at least 0.790. A ball is completed. The coefficient of restitution of the ball depends on the characteristics of both the core and the cover. The PGA compression of the ball is 100 or less, preferably 90 or less.

  In one preferred embodiment, the outer cover layer is polyurethane, polyurea or a polyurethane / polyurea mixture. Polyurethane is a polymer used to form a wide range of products. They are generally formed by mixing two primary ingredients in the manufacturing process. For most commonly used polyurethanes, the two primary gradients are polysotianate (eg, 4,4-diphenylmethane diisocyanate monomer (“MDI”) and toluene diisocyanate (“TDI”) and Their derivatives) and polyols (eg polyester polyols or polyether polyols).

  Many combinations of polyisocyanates and polyols are available as well as other ingredients. In addition, the end-use properties of polyurethane are the polyurethanes used, such as whether the material is thermosetting (cross-linked molecular structure that does not become fluid by heat) or thermoplastic (linear molecular structure that becomes fluid by heat). It can be adjusted according to the type.

Crosslinking occurs between the isocyanate group (—NCO) and the hydroxylated end group (—OH) of the polyol. Cross-linking also occurs with the NH ₂ group of amines and the NCO group of isocyanates to form polyureas. Furthermore, the end-use properties of polyurethane can be controlled by different types of reactants and processing parameters. For example, a catalyst is used to adjust the polymerization rate. Depending on the processing method, the reaction rate can be very fast (as in the case of injection molding (“RIM”) reactions, or on the order of hours or longer (some like casting methods) Thus, very large changes in polyurethane make it suitable for different end uses.

  Polyurethanes are typically classified as thermosetting and thermoplastic. When the polyurethane polymer is cross-linked by a polyfunctional curing agent such as a polyamine or polyol, the polyurethane is “reversibly” “set”. Prepolymers are typically made from polyethers or polyesters. The prepolymer is typically an isocyanate-terminated polymer produced by reacting an isocyanate with a moiety having an active hydroxyl group such as a polyester and / or polyether polyol. The reactive moiety is a hydroxyl group. Diisocyanate polyether is preferred because of its water resistance.

  The physical properties of the thermosetting polyurethane can be substantially adjusted by the degree of crosslinking and the content of curing agent or softener. A strongly crosslinked polyurethane is very hard and strong. When the crosslinking is low, the material has flexibility and elasticity. Thermoplastic polyurethanes are somewhat crosslinked, but are basically by physical means such as hydroxyl bonds. Crosslinks are reversibly broken by raising the temperature, such as during the molding and drawing steps. In this regard, thermoplastic polyurethane can be injection molded or extruded like a sheet or blown film. They can be used up to about 400 ° F. and are available in a wide range of hardness.

  Polyurethane materials suitable for the present invention are produced by polyisocyanates, polyols, and optionally one or more chain extenders. The polyol component includes suitable polyether- or polyester polyols. Further, in an alternative embodiment, the polyol component is a polybutadiene diol. Conjunctive bulking agents include, but are not limited to, diols, avian all, and amine bulking agents. Any suitable polyisocyanate can be used to produce the polyurethanes according to the present invention. The polyisocyanate is preferably, but not limited to, 4,4′-diphenylmethane diisocyanate (“XDI”); 2,4-toluene diisocyanate (“TDI”); m-xylene diisocyanate. Nert ("XDI"); methylene bis- (4-cyclohexyl isocyanate) ("HMDI"); hexamethylene diisocyanate ("HDI"); naphthalene-1,5, -diisocyanate ("NDI"); 3,3′-dimethyl-4,4′-biphenyl diisocyanate (“TODI”); 1,4-diisocyanate benzene (“PPDI”); phenylene-1,4-diisocyanate; and 2,2 , 4- or 2,4,4-trimethyl hexamethylene diisocyanate ("TMDI") Selected from a group of

  Other less preferred diisocyanates include, but are not limited to, isophorone diisocyanate (“IPDI”); 1,4-cyclohexyl diisocyanate (“CHDI”); diphenyl ether-4,4′-diisocyanate. P, p'-diphenyl diisocyanate; lysine diisocyanate ("LDI"); 1.3-bis (isocyanatomethyl) cyclohexane; and polymethylene polyphenyl isocyanate ("PMDI").

  Additional polyurethane components that can be used in the present invention incorporate TMXDI ("META") fatty acid isocyanate (Cytec Industries, West Patterson, NJ). Polyurethanes based on meta-tetramethylxylene diisocyanate (TMXDI) as a whole have improved UV resistance, heat stability and water resistance. Further, TMXDI (“META”) fatty acid isocyanate exhibits favorable toxicity properties. Furthermore, because it has a low clay, it can be used with a wide range of diols (up to polyurethane) and diamines (up to polyurea). If TMDXI is used, it is typically not necessarily required, but is added as a direct replacement with all or part of other fatty acid isocyanates according to supplier recommendations. Because of the slow reactivity of TMDXI, it is useful to use a catalyst to make the part removal time practical. Hardness, ductile strength, and elongation can be adjusted by adding more materials according to the supplier's instructions.

  The polyurethane selected for use in the golf ball cover is preferably a soft cover layer with a Shore D hardness (plaque) of about 10 to about 55 (Shore C hardness, about 15 to about 75), more preferably About 25 to 55 (Shore C hardness, about 40 to about 75), and most preferably about 30 to about 55 (Shore C hardness, about 45 to about 75), about 20 to about 90 with a hard cover layer, Preferably from about 30 to about 80, more preferably from about 40 to about 70.

  The polyurethane used in the cover layer is preferably about 1 to 310 Kpsi, more preferably about 3 to about 100 Kpsi, and most preferably 3 to 40310 Kpsi for the soft cover layer and for the hard cover layer. 40 to 90 Kpsi.

  Examples of suitable polyurethanes for use in the outer cover layer (or inner cover layer) include, but are not limited to, Bayer Corporation's Texin (R) polyester polyurethane (Texin (R) DP7-1097 and Texin). (Registered trademark) 285 grade) and B.I. F. Thermoplastic polyester polyurethanes, such as Goodrich Company's Estane® polyester polyurethane (such as Estane® X-4517). The thermoplastic polyurethane material can also be mixed with soft ionomers or other ionomers. For example, there are polyamides that blend well with soft ionomers.

Other soft, relatively low bend non-ionomer thermoplastics or thermoset polyurethanes also provide the desired operability without negatively impacting the superior flight distance that non-ionomer materials can be obtained with higher acid ionomer components. Can be used to produce an outer cover layer or other inner cover layer as long as durability is achieved. These include, but are not limited to, thermoplastic polyurethanes, such as, but not limited to, Dow Chemical's Pellethane® thermoplastic polyurethanes; U.S. Pat. Non-ionomer thermoset polyurethanes including those disclosed in US Pat. No. 5,334,673. There are two types of thermoplastic polyurethanes; fatty acid polyurethanes and aromatic polyurethanes. The fatty acid material is made from a polyol or polyols and a fatty acid isocyanate such as H ₁₂ MDI or HDI, and the aromatic material is produced from an aromatic isocyanate such as MDI or TDI and a polyol or polyols. Thermoplastic polyurethanes are produced from mixtures of fatty acids and aromatic materials such as mixtures of HDI and TDI with polyols or polyols.

  In general, fatty acid thermoplastic polyurethanes have light resistance which means that they will not yellow when exposed to ultraviolet light. On the other hand, aromatic thermoplastic polyurethane is easily yellowed by irradiation with ultraviolet rays. One way to reduce the yellowing of the aromatic material is to coat the final ball product with a pigment such as titanium oxide so that the ultraviolet light does not reach the surface of the ball. Another method is to add UV absorbers, optical brighteners and stabilizers to the clear coating of the outer cover, or to the thermoplastic polyurethane itself. By adding UV absorbers and stabilizers to thermoplastic polyurethanes and coatings, aromatic polyurethanes can be effectively used as an outer cover layer for golf balls. This is advantageous because aromatic polyurethanes typically have better damage resistance than fatty acid polyurethanes, and aromatic polyurethanes are typically less costly than fatty polyurethanes.

  Other suitable polyurethane materials for use in the golf balls of the present invention include injection molded reaction ("RIM") polyurethanes. RIM is a highly reactive liquid that is injected into a mold, usually mixed by impingement, and / or mechanically mixed in an in-line device such as a “peanut mixer”, whereby it is primarily polymerized and homogeneous in the mold. A molded product is formed. This RIM process typically reacts one or more reactive components, such as polyether polyols or polyester polyols, rapidly with activated hydrogen oxide and one or more isocyanate coating components, sometimes in the presence of a catalyst. Including that. The components are stored in a separate tank before molding, first mixed in a mixing head upstream of the mold and then injected into the mold. The liquid stream is measured to the desired weight ratio, fed to the impingement mixing head, and stirred under high pressure, for example, 1500 psi to 3,000 psi. The liquid streams collide with each other in the mixing chamber of the mixing head, and the mixture is injected into the mold. One of the liquid streams typically contains a reaction catalyst. The components after they are mixed in a gel form react rapidly to form a polyurethane polymer. Polyurea, epoxy, and various unsaturated polyesters are molded by RIM.

  Examples of suitable RIMs that can be used in the present invention include, but are not limited to, Bayer Corp. Bayflex® Elastomer Polyurethane RIM System from Pittsburgh, Baydur® GS Solid Polyurethane Urethane RIM System, Prism® Solid Polyurethane RIM System, and Dow Chemical (Michigan, Michigan, USA) Spectrim® MM 373-A (isocyanate) and Spectrim® reaction moldable polyurethane and polyurea system including 373-B (polyol), Elastrit® from BASF (Persippany, NJ) There is an SR system. Preferred RIM systems include Bayflex (R) MP-10000, Bayflex (R) MP-7500 Bayflex (R) 110-50, with or without increased weight. Further preferred examples are polyols, polyamines and isocyanates formed by recycling polyurethanes and polyureas. Further, these various systems can be modified by incorporating a butadiene component in the diol agent.

  A preferred embodiment of a golf ball having at least one inner cover layer and / or outer cover layer has a fast chemical reaction component. This component comprises at least one material selected from the group consisting of at least polyurethane, polyurea, polyurethane ionomer, epoxy, and unsaturated polyester, and is preferably polyurethane, polyurea or a mixture of polyurethane and / or polymer. . A particularly preferred form of the present invention is a golf ball having a cover made of a polyurethane or polyurea mixture.

  Polyol components typically include stabilizers, flow modifiers, catalysts, combustion modifiers, blowing agents, extenders, pigments, optical brighteners, and release agents that change the physical properties of the cover. Contains additives. The polyurethane / polyurea component molecules obtained from the recycled polyurethane can be added to the polyol component.

  The golf ball inner cover layer or single cover layer according to the present invention formed from a polyurethane material is typically 0 to about 60% by weight, more preferably about 1 to 30% by weight, most preferably 1 to 20% by weight. Contains a bulking agent.

  Additional materials can be added to the inner and outer cover layers according to the present invention as long as they do not affect the operational characteristics of the ball. Such materials include dyes and optical brighteners (see, for example, Ultramarine Blue® from Whittaker, Clark, Danies, South Plainsfield, NJ) (see US Pat. No. 4,679,795); titanium oxide Pigments such as zinc oxide, barium sulfide, and zinc sulfide; UV absorbers; antioxidants; antistatic agents; and stabilizers. In addition, the cover components of the present invention also include those such as plasticizers, metal stearates, process acids, etc., so long as the desired properties achieved by the golf ball cover of the present invention are not lost. Includes softeners such as those disclosed in US Pat. Nos. 5,312,857 and 5,306,857, and glass fibers and inorganic extenders.

Core layer The core of a golf ball is a solid, liquid that will be the core or inner ball (when the ball is a multi-layer ball, at least one cover layer) with the desired COR, compression, hardness and other physical properties. Or other materials.

  The core of the golf ball of the present invention typically has a coefficient of restitution of 0.750 or more, more preferably 0,770 or more, and a PGA compression of 90 or less, preferably 70 or less. Further, in certain applications, the coefficient of restitution is about 0.780 to 0.790 or higher.

  The core of the golf ball of the present invention is preferably a solid, but can be any other type of core known in the art, such as spools, liquids, hollow bodies, metals, and the like. The term “solid core” is used herein not only for one-piece cores but also for cores having a separate solid layer above the central core and below the cover. The core usually has a weight of about 25 to about 40 grams, preferably about 30 to 40 grams. U. S. G. A. Alternatively, heavy and large cores and light and small cores can also be used if the R & A criteria need not be met.

  When the golf ball of the present invention has a solid core, this core is pre-cured consisting of a high cis content polybutadiene and a metal salt of an alpha, beta, ethylenically unsaturated carboxylic acid, such as zinc mono- or diacrylate or methacrylate. Or a lightly cured elastomer composition. In order to achieve a high coefficient of restitution and / or increase the hardness of the core, the manufacturer can include a small amount of metal, such as a small amount of zinc oxide. In addition, the final product may contain U.S. by adding more metal oxide than is necessary to obtain the desired modulus to increase the core weight. S. G. A. Approaching the 1.620 ounce limit.

  Other materials used in the core composition include, but are not limited to, compatible rubbers or ionomers, including low molecular weight fatty acids such as stearic acid. A free radical initiator such as a peroxide may be mixed into the core composition in order to cause a curing or crosslinking reaction by application of heat and pressure. The core may be formed by other golf ball molding methods known in the art.

  The wound core can have a liquid, solid, gel or multilayer core. A wound core is typically a natural or artificial rubber thread or a thermoplastic or thermoset elastomeric thread such as polyurethane, polyester, polyamide, etc., on a solid, liquid, gel or gas filled core. Can be obtained by wrapping and forming a rubber thread layer and then covering with one or more mantles or cover layers. Furthermore, before applying the cover layer, the pincushion core further improves the binding of the pincushion core during application of the cover to the adhesive layer, protective layer, or pincushion core, or ultimately as a golf ball. It may be treated or coated with other materials.

  Since the core material is not an integral part of the present invention, the particular core material used with the cover composition of the present invention is not specifically described herein.

Golf Ball Manufacture The golf ball of the present invention reduces or eliminates the need for a pullable pin that supports the core (core or inner cover) within the mold. However, there may be a “knock-out” pin useful for pulling the member out of the mold. In the prior art, pullable pins are used to support the core or core and additional layers. The pin is withdrawn when it is supported by the cover material until it is supported by the cover material until sufficient cover material is filled into the mold and supports the core without the need for help. Forming a golf ball without using a pullable pin reduces the amount of processing incidental to making the ball product. Furthermore, the cover material adheres to the pullable pins, eliminating the need for frequent cleaning of the mold.

  According to a preferred technique of the present invention, one or more deep dimples are formed to extend to or into the inner layer or golf ball components. In particular, each layer has dimples formed by cavities formed with dimples having the same geometric coordinate pattern as cavities formed with other corresponding dimples. The core or core and inner layer are aligned such that dimples are formed to overlap each other in successive layers.

  For example, for the dimple of the preferred embodiment of the present invention, the outer layer is responsible for part of the entire depth and the inner layer is responsible for the remaining part. In conventional golf balls, the dimple depth, which is typically about 0.010 inches, is usually less than the cover thickness and does not touch the next layer or even close to the next layer. there were. Therefore, a minimum cover thickness is required to have a desired depth of dimples. In the golf ball of the present invention, two or more layers can form dimples, and therefore each layer can be very thin (less than 0.010 inches), so the cover thickness is greater than the dimple depth. Removed the need.

  Further, as described above, the golf ball of the present invention can incorporate deep dimples and double dimples (in-dimple dimples) or dimples formed in multiple layers.

  In making a golf ball according to a preferred embodiment of the present invention, a single cover layer or inner cover layer (or mantle layer) is formed around a core (preferably a solid core). The cover layer is formed by any forming method already known in the art. Examples of molding methods include, but are not limited to, injection molding, transfer molding, reaction injection molding, liquid injection molding, casting, compression molding, and the like.

  In a multi-layer golf ball as shown in FIGS. 3 and 4, the outer layer 160 is molded around the inner layer 150. The core (or core and inner layer) is supported by one or more, preferably two or more, support pins or protrusions that form deep dimples in contact with the core or intermediate layer. That is, the outer surface of the support pin or protrusion forms the inner surface of the deep dimple.

  The core (or core and inner layer) is held by the holding force produced by the dimple design, i.e. by making the core or intermediate ball assembly deep enough to grip the ball by applying a slight load. The Neglecting the friction, only the force generated is radial, and the radial loading is proportional to the radial interference between the deep dimple and the core, or the core and the inner layer.

  The number of deep dimples in the golf ball of the present invention varies as desired. A certain number and geometric pattern is preferred, but any number and pattern of deep dimples may be used. The geometric pattern is preferably arranged approximately in the center around the pole of the ball. Given the limited number of coordinates, i.e. points, it is generally not possible to precisely center a particular geometric pattern with a certain shape, such as a triangle. In addition, it is desirable to move the pattern slightly to absorb other forces on the other side of the ball (due to forming a layer).

  9 and 10 are plan views (ball hemispheres) of a golf ball having a preferred deep dimple arrangement. FIG. 9 shows a golf ball having a triangular arrangement of three deep dimples arranged approximately symmetrically around the pole 44. FIG. 10 shows a golf ball having a diamond-like arrangement of three deep dimples arranged approximately symmetrically around the pole 44. These figures are for illustration purposes and any number, i.e. deep dimples 1, 2, 3, 4, 5, 6, etc. can be used. Deep dimples have aerodynamic effects with a symmetrical arrangement, but do not have to be symmetrical. This will result in the final product ball reaching deep dimples from the outer layer to the next inner layer and / or core. To this ball, a multilayer cover layer with the same or different material and thickness may be added by using this method.

  The position of the deep dimple may be any position such as a latitude of about 30 degrees, 40 to 45 degrees, 50 to 60 degrees in each hemisphere. That is, deep dimples can be located in one or both hemispheres at a latitude of about 60 degrees from a grid of about 30 degrees in the region along the outer surface of the ball. Preferably, the deep dimples are located at or above a latitude of about 40 to 45 degrees in each hemisphere. As used herein, the latitude for the position of the ball dimple is defined as 0 degrees latitude on the equator and 90 degrees latitude on each pole.

  FIG. 13 is a graph showing the relationship between the position of deep dimples on the golf ball and the acting force on the core. Table 1 below shows the data shown in FIG.

他の好ましい実施例においては、コア又は中間ボール（コアプラス一又は複数のマントル又は内側カバー層）がコアに近接して、又はコアまで延びる一又は複数の深いディンプルにより支持される。深いディンプルの位置はボール上のどこでもよく、各半球の緯度３０度、緯度４０度から４５度、緯度５０度から６０度などの位置とすることがｋでいる。好ましくは、深いディンプルは、各半球について緯度４０度から４５度、或いはそれ以上である。深いディンプルの数は所望により種々のものとすることができる。幾何学的パターンは好ましくはボールの極の回りの略中央に位置する。三角のような特定の形状のパターンはでは正確に極の回りに配置することは難しい。更に、パターンを僅かに移動させてボールの他の側の別の力（層の形成に起因する）を吸収するようにすることが望ましい。これにより、外側層から次の内側層又はコアに延びる深いディンプルが存在する最終製品のボールが得られる。上述のように、同一の又は異なる材料と厚さを持つ多層カバー層をこの方法を用いてボールに加えることができる。

In another preferred embodiment, the core or intermediate ball (core plus one or more mantles or inner cover layer) is supported by one or more deep dimples that extend close to or to the core. The position of the deep dimple may be anywhere on the ball, and it is k that the position of each hemisphere is 30 degrees latitude, 40 degrees to 45 degrees latitude, 50 degrees to 60 degrees latitude, and the like. Preferably, the deep dimples are 40 to 45 degrees latitude or more for each hemisphere. The number of deep dimples can be varied as desired. The geometric pattern is preferably located approximately in the center around the pole of the ball. It is difficult to place a pattern with a specific shape such as a triangle precisely around a pole. It is further desirable to move the pattern slightly to absorb other forces on the other side of the ball (due to layer formation). This provides a final product ball with deep dimples extending from the outer layer to the next inner layer or core. As mentioned above, a multi-layer cover layer with the same or different material and thickness can be applied to the ball using this method.

  FIG. 14 is an external view of a golf ball according to a preferred embodiment of the present invention. This represents the peripheral area defined along the outer surface of the ball. This region corresponds to a preferred region in which one or more deep dimples described herein are defined. In particular, a preferred location for deep dimples is a region along the outer surface of the ball that extends between about 30 degrees and about 60 degrees latitude. The pole of the ball is an axis passing through the ball indicated by PP in FIG. In FIG. 14, the equator is shown as a circumference E that extends around 0 degrees latitude of the ball.

  Many cover and / or mantle layer numbers can be used, and the deep dimples extend over as many layers as desired. For example, a golf ball having a core and three cover layers (first inner cover layer, second inner cover layer, outer cover layer) can be made in accordance with the present invention. The deep dimples may penetrate the first cover layer, the first and second cover layers, or the deep dimples may penetrate all the cover layers to reach the core.

  In addition, if desired, the mantle layer may be colored, visible through the cover layer, or include cosmetic features. The cover layer may also be transparent, translucent, or opaque to enhance the mantle layer.

  Other golf ball manufacturing methods that do not use a core pin include using a tab on the equator of the core and accepting the tab to support the core in which the cavity with the dimples is placed. . Alternatively, the golf ball can have one or more keyways or openings. The cover mold is provided with a side puller that engages the key and holds the placed core.

  The core of the ball is preferably solid and can be used in the range of about 1.0 to 2.0 inches, although a diameter of about 1.2 to about 1.6 inches is preferred. If the ball has a single cover layer, the core size can be up to about 1.660 inches.

  The present invention includes one or more auxiliary layers disposed on the core, preferably adjacent to the core surface. For example, in certain applications, it is preferable to provide a barrier coating to limit moisture transfer to the core. As already mentioned, such barrier coatings or layers are relatively thin. Generally, the thickness of such a coating is at least 0.0001 inches, preferably at least 0.003 inches. Furthermore, an adhesion-enhancing layer can be used between the cover layer and / or the core, or between the cover and the core on which the barrier coating is provided. Such adhesion enhancing layers are well known in the art and can be used with the inventive features described herein. See, for example, US Pat. No. 5,820,488, incorporated herein by reference.

  The inner cover layer molded over the core is preferably about 0.0005 inches to about 0.15 inches in thickness. The inner ball, including the core and inner layer, or two-piece ball core, is preferably 1.25 to 1.60 inches in diameter. The cover layer has a thickness of about 0.0005 inches to about 0.15 inches. The core, inner cover layer, and outer cover layer (or core and single cover layer) are generally U.D. S. G. A. Forms a luffball with a diameter of 1.680 inches in diameter, which is the smallest diameter allowed by the rule, or larger and weighs less than 1.62 ounces. If S. G. A. The rules are not a problem and golf balls with different weights and diameters can be formed if desired.

  In a particularly preferred embodiment of the present invention, the golf ball has a dimple pattern with a dimple occupancy of 65% or more, preferably 75% or more, more preferably 80 to 85%. In a preferred embodiment of the invention, there are 300 to less than 500, preferably 340 to 440 dimples.

  In particular, the arrangement and the total number of dimples are not fixed, and may be appropriately selected within a well-known range. For example, the dimples can be arranged in an octagon, dodecagon, or decagon. The total number of dimples is generally about 250 to 600, especially about 300 to 500.

  In a preferred embodiment, the golf ball is typically durable, abrasion resistant, and can be coated with a non-yellowing finish if desired. The finish coat may have certain optical brighteners and / or pigments to improve the gloss of the final product golf ball. In a preferred embodiment, 0.001 to about 10% optical brightener can be added to one or more finish coatings. If desired, an optical brightener may be added to the cover material. One preferred finish coating type is a solvent-based urethane coating, which is well known in the art. It is also possible to apply a transparent outer coating on the final product ball.

  Golf balls typically include a logo and other marks printed on the surface of the dimpled ball. A paint, typically clear paint, is applied to protect the cover and improve the appearance before it is finished as a product. FIG. 11 is an enlarged view of the cross section of the dimple formed on the surface of the golf ball prior to coating. Most often, the dimples are planar and circular. Normally, deep dimples as shown in FIG. 11 are formed as recesses or depressions. The cross-sectional shape of the dimple is defined by a part of a curved surface such as a circle, an ellipse, or a super ellipse. For example, the cross-sectional shape of the dimple shown in FIG. 11 is a part of a circle. The dimples are circumscribed by an upper edge that is continuously connected to a land area on the outer surface of the golf ball where no dimples are formed. This edge is substantially inclined from the land region as a steep slope forming a dimple. The edge is usually rough before painting, and becomes a little bit after painting.

  The cover layers of various compositions of the present invention can be produced by conventional melt mixing methods and other methods known in the art. For example, the cover material can be mixed in a two-roll mill, a Banbury® type mixer, or an extruder prior to neutralization. After mixing, neutralization takes place in the molten state in a Banbury® type mixer. The mixed composition is then formed into slabs, pellets, etc. and held in that state until needed for molding. Apart from that, a simple dry mixture of pelletized or powdered material (if neutralized if necessary) and color masterbatch is prepared and fed directly to the injection molding machine where the mold Prior to the injection, the agitation part of the barrel is agitated. If necessary, additives such as ionomer extenders are added and stirred uniformly before the molding process begins.

  The golf balls of the present invention are manufactured by a molding process, which includes but is not limited to methods currently well known in the art. As already mentioned, golf balls can be manufactured, for example, by injection molding, reaction injection molding (RIM), liquid injection, compression molding, etc., and new around a spool, solid, or other type of core. It is manufactured by molding a cover composition and typically producing an inner ball with a diameter of 1.50 to 1.67 inches.

  Alternatively, the cover layer may be injected around the core or core and inner layer, such as by a cast polyurethane system. An outer layer is subsequently molded around the inner layer to produce a golf ball having a diameter of 1.620 inches or more, preferably 1.680 inches or more. This is not currently preferred because it is difficult to inject material around deep dimple protrusions. Any type of core, such as a solid core or a pincushion core, can be used in the present invention, but a solid molded core is preferred over a pincushion core because of its low cost and excellent operability. Standards for both minimum diameter and maximum weight are established by the United States Golf Association (USGA), but all golf balls must be designed to meet these standards. Not in.

  In compression molding, a hemispherical shell (preformed) with a smooth surface is placed around the core in a mold with the desired inner cover thickness. The core and shell are then fired at 200 ° F. to 300 ° F. for 2 minutes to 10 minutes to melt the shell and form a single intermediate ball. Furthermore, the intermediate balls can be manufactured by injection molding, in which a cover layer is injected directly around a centrally located core in a 50 ° F. to 100 ° F. intermediate ball mold. Subsequently, the outer cover layer is molded around the core and inner layer by similar techniques to form dimples of 1.680 inches or larger. Adhesion promoters may be used to improve adhesion between the inner cover layer and the outer cover layer, or between any cover layer and / or core. Several adhesion promoters such as surface abrasives, corona treatments, etc. are well known in the art. Preferred adhesion promoters are chemical adhesives such as silanes or preferably other silicon compounds such as N- (2-aminoethyl-3) -aminopropyl trimethoxysilane. The intermediate golf ball (core and inner cover layer) is dipped into the drug or sprayed with the drug, and then the outer cover layer is formed over the drug-treated inner cover layer. Multi-layer cover layers are processed one or more times if necessary or desired.

  A typical method of casting the cover around the core or core and inner layer consists of molding using two molds (eg, book type) heated to about 80-180 ° F. Cover materials such as polyurethane are heated to about 80-180 ° F. The material gel time is approximately 20 to 90 seconds and the molding stop time (heating step) is about 2 to 8 minutes. After the material forms the cover, the mold is opened and the ball is removed from the mold.

  After molding, the manufactured golf ball is subjected to various processing steps such as buffing, trimming, cutting, tumbling, painting, etc. as disclosed in US Pat. No. 4,911,451, incorporated herein by reference. Is called.

  The resulting ball can be manufactured more efficiently and at a lower cost than conventional golf balls. In addition, the golf ball multilayer cover layers of the present invention can be provided, some of which are very thin (less than 0.03 inches, preferably less than 0.02 inches, more preferably less than 0.03 inches) as required. Less than 01 inches) and can produce golf balls with special performance. For example, a golf ball having a softer outer cover layer and a hard inner cover layer can be manufactured. Alternatively, a golf ball having a hard outer cover layer and a soft inner cover layer can be manufactured. Furthermore, a golf ball in which the inner cover layer and the outer cover layer have the same hardness can be envisaged by the present invention.

  For golf balls having three or more layers, the hardness of the layers may be changed to each other, can be made hard-soft-hard, soft-hard-soft, and whether the hardness has a gradient. You can also make golf balls with bars. The hardness gradient may begin with a hard inner cover adjacent to the core and soften with the outer cover and vice versa. This allows control and flexibility of the characteristics of the golf ball. As already mentioned, the layers may be of the same material or different materials and may be of the same or different thickness.

  Further, as already mentioned, golf balls of the present invention having polyurethane / polyurea (or other suitable material) in either the inner or outer cover layer are produced by a reaction injection molding process (RIM). be able to.

  Golf balls, particularly cover layers, are described in application number no. 09 / 040,798, preferably by RIM or by methods similar to RIM.

  RIM differs from non-reaction injection molding in many ways. The main difference is that in RIM, a chemical reaction takes place in the mold, the monomer or adduct is modified into a polymer, and the composition is liquid. Thus, the RIM mold need not be made to withstand the pressures that occur in normal injection molding.

  Apart from this, the injection molding method is performed at a high molding pressure in the mold cavity by melting a solid resin, using a melted resin having a temperature of about 150 ° C. to 350 ° C., and supplying it to the mold. Is called. Due to this high temperature, the viscosity of the molten resin is usually from about 50,000 to about 1,000,000 centipoise, typically about 200,000 centipoise. In the injection molding method, depending on the size of the molded product, temperature and heat transfer conditions, and the hardness of the material to be injection-molded, resin solidification starts after about 10 to 90 seconds. Thereafter, the molded product is removed from the mold. In the injection molding method, no significant chemical change occurs when the thermoplastic resin is introduced into the mold.

  On the other hand, in the RIM method, the chemical reaction takes less than about 5 minutes, often less than 2 minutes, preferably less than 1 minute, more preferably less than 30 seconds, and often less than 10 seconds. Set the material with.

  The catalyst can be added to the starting material of the RIM polyurethane system as long as the catalyst does not react with the components to which it is bound. Suitable catalysts include those known to be useful for polyurethanes and polyureas.

  Polyol components are typically added to alter the physical properties of the cover, such as stabilizers, flow modifiers, catalysts, combustion modifiers, expansion agents, fillers, pigments, optical brighteners, and release agents. Contains agents. Recycled polyurethane / polyurea component molecules obtained from recycled polyurethane can be added to the polyol component.

  The mold cavity includes support pins and is typically structured similarly to a mold cavity, such as used for injection molding thermoplastic materials such as, for example, ionomer golf covers. However, when RIM is used, there are two different things, one is that tighter pin tolerances are usually required and one is that lower injection pressures are used. The mold is also made from a low strength material such as aluminum.

  The RIM process can provide many improvements to the cover layer. If a plastic product is manufactured to some extent by combining multiple components, this can cause defects in the cover seam, i.e., along the mold separation line, as well as the location of the core pin. This portion is essentially different from the other portions of the cover layer, and becomes brittle or more stressed. The cover layer produced by RIM improves the durability of the golf ball cover by making it uniform or seamless, where the properties of the cover material along the separation line are the other parts including the poles of the cover. Same as cover material. The increase in durability is believed to be the result of the reaction mixture being evenly distributed within the sealed mold. This uniform distribution of the injected material suppresses the occurrence of knit-lines and molding defects caused by temperature differences and / or differences in material reactions. RIM typically provides a uniform molecular structure, density and stress distribution compared to conventional injection molding methods.

  The golf balls of the present invention, in particular the cover layer, can be formed by liquid injection molding techniques or other techniques known in the art.

  Golf balls formed in accordance with the present invention can be applied using conventional two-component spray coating, or can be applied during RIM processing using, for example, an in-mold coating method.

  FIG. 15 shows a preferred embodiment molding apparatus 1000 according to the present invention. The molding apparatus 1000 has two halves 020, 1040, each defining a hemispherical portion of the molding chamber 1024, 1040. There are a plurality of raised protrusions or support pins 1032 along the outer surface of the hemispherical portion of the molding chamber 1024. These raised areas or support pins form dimples in the golf ball cover layer formed using the molding apparatus 1000. There are also a plurality of support pins 1026, 1028, 1030 along the outer surface of the hemispherical molding chamber 1024. These raised areas are higher than the raised area 1032. In particular, the raised regions 1026, 1028, 1030 form the deep dimples described herein. These raised areas are used to hold a golf ball core (or intermediate ball assembly) placed in the mold. A passage 1022 is provided in the half mold 1020 so that it can be understood. The passage 1022 is for communication and is for introducing a fluid molding material into the molding chamber. The molding apparatus 1000 also has a second mold part or plate 1040. Plate 1040 also defines a hemispherical molding chamber 1044 having a plurality of raised areas or support pins on the outer surface. In particular, the raised areas 1046, 1048 are provided in the same manner as the raised areas 1026, 1028, 1030 already described. The forming plate 1040 also defines a channel 1042 that extends from the forming chamber 1044 to the outside of the plate. Most preferably, the mold channel 1042 is aligned with the channel 1022 of the other plate 1020 when the mold is closed to provide a single passage that communicates the mold chamber and the exterior of the mold. Golf ball cores placed in the molding chambers 1020, 1040 are supported by various raised regions 1026, 1028, 1030, 1046, 1048, as described above. A golf ball 1010 or element is manufactured.

  With respect to forming various golf balls, the present invention also provides a method of forming a golf ball having at least one deep dimple. Preferably, the method is as follows. A golf ball assembly is provided that includes a core or core and / or one or more intermediate layers disposed thereon. The molding apparatus includes a spherical molding chamber having a raised region having a first number or group defined along a mold surface for forming a plurality of dimples on the outer layer of the golf ball. The molding chamber also includes at least one other raised region having a height greater than or equal to the thickness of the cover layer formed on the golf ball. The method also includes placing an intermediate golf ball assembly in a molding chamber and supplying a flowable material, such as a flowable cover material, to the mold. The material is introduced so as to be fed around an intermediate ball assembly disposed in the molding chamber. Preferably, the method also includes the step of curing the flowable material thereby forming the outer cover layer. A key feature of this technology is that when the intermediate golf ball assembly is placed in the mold, the other raised areas of the mold chamber preferably support and support the intermediate golf ball assembly in the mold chamber. is there.

  In particular, the golf ball of the present invention is not particularly limited with respect to the structure. Solid golf balls, including one-piece golf balls, two-piece golf balls, and multilayer golf balls having three or more layers and wound golf balls, are manufactured using well-known ball materials and conventional manufacturing methods.

  The invention is further illustrated by the following examples, in which specific component proportions are given by weight. It will be understood that the present invention is not limited to these examples, and that various modifications and variations are possible without departing from the spirit and scope of the present invention.

EXAMPLE A golf ball according to the present invention was produced. A golf ball has a core, a mantle or inner cover, and an outer cover. The mantle was an ionomer, and the outer cover was a polyurethane cover formed by the RIM method (ball type A). The used mold has six support pins (for each hemisphere) that form deep dimples located in a triangular shape as shown in FIG. 9 in each hemisphere. The balls were tested against other balls as shown below. The results are shown in Tables 3 to 5 below.

Type B balls are golf balls that have a dual core, an ionomer mantle, and an injection molded polyurethane cover. Type C balls are balls having a single core, an ionomer mantle, and an ionomer cover. Type D balls are commercial grade Strata (R) Tour Professional ^TM balls, Type E balls are commercial grade Top-Flite (TM) Z-Balata ( ^TM ) 90 golf balls, Type F balls Is a commercial grade Nicke® Tour Accuracy TW ^™ ball and the Type G ball is a commercial grade Titleist® Pro VI ^™ ball.

  The coefficient of restitution (COR) was measured by firing with an air gun at a speed of 125 feet per second towards an iron plate 12 feet away from the muzzle. The speed of rebound was measured. The coefficient of restitution is the rebound rate divided by the rate of fire.

The damage test was carried out as shown below. A sand wedge (56 degree loft) with sharp grooves was attached to a mechanical swing machine. The club swing speed was 60 mph. The club face was cleaned with a nylon bristol brush after every hit. A minimum of 3 samples of each ball were tested. Each ball hit at a different position so as not to overlap three times. The details of the club face are important and include the following:
Groove width-0.025 inch (cut with a mill cutter, leaving a sharp edge in the groove; do not sandblast or post-process after cutting)
Groove depth-0.016 inch Groove spacing (from groove edge to nearest edge)-0.105 inch For each impact, a point value was given for the worst damage according to Table 2 below.

打撃の終了後、平均のポイント値が決定された。この平均ポイント値は、即ちランクは下記のチャートに相関される。

After the hit, the average point value was determined. This average point value, ie, rank, is correlated to the chart below.

耐損傷性は下記の手順により測定された：ゴルフボールが毎秒１３５フィートの速度で、リーディングエッジの曲率半径が１／３２インチで、ロフト角が５１度、ソールの曲率半径が２．５インチ、バウンス角が７度のピッチングウエッジのリードエッジに向けて発射される。

Damage resistance was measured by the following procedure: golf ball at 135 feet per second, leading edge radius of curvature of 1/32 inch, loft angle 51 degrees, sole radius of curvature 2.5 inches, Fired toward the lead edge of a pitching wedge with a bounce angle of 7 degrees.

  The ball to be tested was evaluated for damage resistance on a scale of 1 to 5. 1 represents a complete cut up to the cover color core. 2 indicates that the cover is not completely penetrated but the surface is destroyed. 3 represents that which does not destroy the surface but leaves a permanent depression. 4 represents a slight fold, but 3 is not as bad. 5 represents that no damage is found by just looking.

  Cut and scratch tests were performed on the golf balls of the present invention (type A balls), two test golf balls (types B and C), and two commercial grade golf balls (type FtoG).

  The initial speed is U.V. S. G. A. The speed of the ball when hit with a hammer at a speed of 143.8 feet per second according to the test specified in.

  Here, the “Shore D hardness” or “Shore C hardness” of the core or cover element is usually measured according to ASTM D-2240, except when measured on the surface of a curved molded element rather than a piece. . Furthermore, the Shore C and Shore D hardness of the cover is measured with the cover remaining on the core. When measured on a dimple-formed cover, the Shore C and Shore D hardnesses are measured at the land portion of the cover where the dimple is formed.

  The spin rate test was performed on the multi-layer golf ball product of the present invention (type A) and two other test multi-layer cover golf balls (type B and type C) with a driver, 5 iron, 9 iron and pitching iron.

  For comparison, two commercial grade golf balls (types D and E) were also tested. A golf ball test machine was set to emulate an average tour pro hit for each club.

タイプＡのボールは、カット及び擦り傷に対する結果は、仮によくないとしても、ほとんどの他のタイプのボールと同様であることを留意されたい。

It should be noted that Type A balls have similar results to most other types of balls, even if the results for cuts and scratches are not good.

  Below are the spin rate and distance test results.

タイプＡのボールは他の種類のボールと比較し得るものであることを留意されたい。

Note that Type A balls can be compared to other types of balls.

  The above description is considered to be the preferred embodiment of the invention at the present time. However, it will be understood that variations and modifications apparent to those skilled in the art may be made without departing from the invention. Accordingly, the foregoing description is intended to cover all modifications and improvements, including equivalents made within the spirit and scope of the present invention.

1 illustrates a golf ball of a preferred embodiment of the present invention having a core and a cover layer having a single dimple, with one or more dimples extending through the cover to the core below or into the core. . FIG. 2 is an opposing cross-sectional view of the preferred embodiment golf ball shown in FIG. 1. FIG. 6 shows a golf ball of another embodiment of the present invention, having a core element and a cover element, the cover element including an outer cover layer formed with an inner cover layer and dimples, wherein one or more dimples of the outer cover layer are provided. It extends to the inner cover layer or into the inner cover layer. FIG. 4 is an opposing cross-sectional view of the preferred embodiment golf ball shown in FIG. 3. 1 is a partial detailed cross-sectional view of a preferred embodiment golf ball having a core and cover according to the present invention, showing a double radius dimple extending through the cover to the underlying core. FIG. FIG. 2 is a cross-sectional view of a golf ball having a core and cover according to a preferred embodiment of the present invention, showing double radius dimples extending through the cover layer to the outer surface of the core. 1 is a partial cross-sectional detail view of a golf ball having a core, an inner cover layer, and an outer cover layer of a preferred embodiment of the present invention, the outer cover layer having double radius dimples extending into the inner cover layer. 1 is a partial cross-sectional detail view of a golf ball having a core, an inner cover layer, and an outer cover layer of a preferred embodiment of the present invention, showing a double radius dimple extending through the outer cover layer of the golf ball to the inner cover layer. ing. In the top view of the golf ball of the preferred embodiment of the present invention, it has a first normal dimple with three deep dimples arranged in a triangle around the golf ball pole. FIG. 2 is a plan view of a golf ball of the preferred embodiment of the present invention having a first normal dimple with four deep dimples in a diamond shape around the pole of the golf ball. 1 is a view showing a golf ball having a core, an inner cover, a mantle layer, and an outer cover layer according to a preferred embodiment of the present invention, showing dimples extending from the outer cover layer to the mantle layer. FIG. 2 is a plan view of a golf ball having dimples formed on two cover layers according to a preferred embodiment of the present invention, showing dimples formed on the inner cover layer and outer dimples formed on the outer cover layer. 4 is a graph showing the relationship between the position of several dimples on a golf ball according to the present invention and the acting force in a self-supporting cavity during molding. 1 is a perspective view of a golf ball showing an area defined along the outer surface of the ball. FIG. 1 is a schematic view of a preferred embodiment of a molding apparatus and a golf ball core according to the present invention.

Claims (19)

A core defining a plurality of depressions along the outer surface;
A cover layer provided on the core and defining a plurality of holes extending through the cover layer to the core;
Golf ball having.   The golf ball according to claim 1, wherein at least one hole defined by the cover layer overlaps at least one recess defined by the core.   The golf ball according to claim 1, wherein all of the holes overlap the depression.   The golf ball according to claim 1, further comprising a mantle layer provided between the core and the cover layer and defining a plurality of holes.   The golf ball of claim 4, wherein at least one hole defined in the mantle layer overlaps at least one of the holes in the cover layer.   The golf ball of claim 1, wherein each hole has a depth in the range of about 0.51 mm (0.002 inch) to about 3.56 mm (0.140 inch).   The golf ball of claim 1, wherein each of the holes has a diameter in the range of about 0.025 inches to about 0.25 inches.   The golf ball according to claim 1, wherein the cover layer is made of an ionomer.   The golf ball of claim 1, wherein the cover layer comprises a polyurethane material selected from the group consisting of polyurethane, polyurea, polyurethane / polyurea, polyurethane / ionomer, or a mixture thereof. A core defining at least one indentation along the outer surface;
A plurality of holes provided on the core and extending through the cover layer to the core, wherein the holes overlap the recesses of the core and the cover layer;
Golf ball having. The golf ball according to claim 10, further comprising a mantle layer that is disposed between the core and the cover layer and defines a hole in which a hole of the cover layer and a recess of the cover overlap each other .   The golf ball of claim 10, wherein each hole has a depth in the range of about 0.002 inches to about 0.140 inches.   The golf ball of claim 10, wherein each hole has a diameter in the range of about 0.025 inches to about 0.25 inches.   The golf ball according to claim 10, wherein the cover layer is made of an ionomer material.   The golf ball according to claim 10, wherein the cover layer is made of a polyurethane material. With the core;
At least one intermediate layer provided around the core, the intermediate layer defining at least one hole extending through the intermediate layer to the core;
A cover layer provided around the intermediate layer, the cover layer extending through the cover layer and defining at least one hole overlapping the hole of the intermediate layer;
Have
Each of the holes is a golf ball having a depth in the range of about 0.51 mm (0.002 inch) to about 3.56 mm (0.140 inch).   The golf ball of claim 16, wherein each hole has a diameter in the range of about 0.025 inches to about 0.25 inches.   The golf ball according to claim 16, wherein the cover layer is made of an ionomer material.   The golf ball according to claim 16, wherein the cover layer is made of a polyurethane material.

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