Patent Application
20120165129
The present invention relates generally to a golf ball, and a method of manufacturing the golf ball. In particular, a cover layer on the golf ball includes areas having a higher hardness and areas having a lower hardness.
The game of golf is an increasingly popular sport at both the amateur and professional levels. A wide range of technologies related to the manufacture and design of golf balls are known in the art. Such technologies have resulted in golf balls with a variety of play characteristics. For example, different golf balls are manufactured and marketed to players having different golfing abilities, such as different swing speeds.
Similarly, a golfer may use different golf balls having different play characteristics depending on the golfer's preferences. For example, different dimple patterns may affect the aerodynamic properties of the golf ball during flight, or a difference in the hardness of the cover layer may affect the rate of backspin. With regard to hardness in particular, a golfer may choose to use a golf ball having a cover layer and/or a core that is harder or softer. A golf ball with a harder cover layer will generally achieve reduced driver spin, and achieve greater distances. However, a harder cover layer will generally cause a lower rate of spin, such that the golf ball will be better for drives but more difficult to control on shorter shots. On the other hand, a golf ball with a softer cover will generally experience more spin and therefore be easier to control and stop on the green, but will lack distance off the tee.
A wide range of golf balls having a variety of hardness characteristics are known in the art. Generally, the hardness of a golf ball is determined by the chemical composition and physical arrangement of the various layers making up the golf ball. Accordingly, a number of different golf ball materials are mixed and matched in various combinations and arrangements to create golf balls having different hardness values and different hardness profiles.
However, designing golf balls to achieve desired hardness characteristics suffers from at least several difficulties. Generally, the construction of known golf balls requires that a wide range of design variables such as layer arrangement, materials used in each layer, and layer thickness be balanced against each other. Changes to any of these variables may therefore improve a desired hardness only at the expense of other play characteristics. Additionally, materials costs and design costs associated with known golf ball constructions may unduly increase the cost of the golf ball to the end consumer. Perhaps most importantly, known golf balls generally cannot simultaneously achieve the advantageous play characteristics associated with high cover hardness (greater distances) while also achieving the advantageous play characteristics associated with low cover hardness (greater spin).
Therefore, there is a need in the art for a system and method that addresses the shortcomings of the prior art discussed above.
Generally, this disclosure provides golf balls having a cover layer where certain portions of the cover layer are made from an ionomer material, and other portions of the cover layer are made from a polyurethane material. The different materials may have different physical properties, such as hardness or compressibility, that result in the golf ball exhibiting various play characteristics.
In one aspect, this disclosure provides a golf ball comprising: a core; and a cover layer, the cover layer substantially surrounding the core and including a plurality of dimples and at least one land area separating the dimples; wherein the cover layer includes a first portion, the first portion of the cover layer having a first hardness, and a second portion, the second portion of the cover layer having a second hardness; the first portion and the second portion being laterally adjacent to each other within the cover layer; the first portion comprising a polyurethane material; the second portion comprising a ionomer material; and the first hardness is different from the second hardness.
In another aspect, this disclosure provides a golf ball comprising: a core; and a cover layer substantially surrounding the core, the cover layer being formed of a first material having a first hardness, and the cover layer having a plurality of dimples and at least one land area thereon; the plurality of dimples being arranged on the cover layer in a first pattern; the at least one land area being arranged on the cover layer in a second pattern, the first pattern and the second pattern being non-overlapping patterns; wherein the cover layer is coated with a second material, the second material having a second hardness, such that the coating material overlaps at least a portion of one of the first pattern and the second pattern but substantially does not overlap the other of the first pattern and the second pattern; the second hardness is different from the first hardness; the first material comprises a material that is selected from the group consisting of: an ionomer material, and a polyurethane material; the second material comprises a material that is selected from the group consisting of: an ionomer material, and a polyurethane material; and the second material is different from the first material.
In yet another aspect, this disclosure provides a golf ball comprising: a core; a cover layer substantially surrounding the core; the cover layer being formed of a cover material; the cover material comprising a material that is selected from the group consisting of: an ionomer material, and a polyurethane material; the cover material having a first hardness and a first compressibility; the cover layer including one or more grooves extending radially inward from an outer surface of the cover layer; and a groove material disposed within the one or more grooves; the groove material having a second hardness and a second compressibility; wherein the groove material comprises a material that is selected from the group consisting of: an ionomer material, and a polyurethane material; the groove material being different from the cover material; the first hardness being different from the second hardness, and the first compressibility is different from the second compressibility.
Other systems, methods, features and advantages of the invention will be, or will become, apparent to one of ordinary skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages be included within this description and this summary, be within the scope of the invention, and be protected by the following claims.
The invention can be better understood with reference to the following drawings and description. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. Moreover, in the figures, like reference numerals designate corresponding parts throughout the different views.
Generally, the present disclosure relates to a golf ball having areas on the cover layer that are relatively hard and areas on the cover layer that are relatively soft. The hard areas may be made of a ionomer material, and the soft areas may be made of a polyurethane material.
The relatively hard areas may correspond to at least some of the dimples in the cover layer, and the relatively soft areas may correspond to at least part of at least one land area between the dimples. Alternatively, the hard areas (or soft areas) may be configured in one or more grooves in the otherwise soft (or hard, respectively) cover layer.
As a result of these arrangements, the golf ball may experience a lower rate of spin when struck with a larger force (such as during a drive) while also experiencing a higher rate of spin and increased control when struck with a smaller force (such as during a chip). The golf ball therefore achieves improved play characteristics associated with harder cover layers (such as longer distance) during drives, while also achieving improved play characteristics associated with softer cover layers (such as higher spin) during short shots.
This disclosure further relates to methods of manufacturing such a golf ball.
The plurality of dimples 104 may generally be arranged on the cover layer in any pattern, as may be known in the art of golf balls. Various known dimple packing patterns are known in the art. Dimples 104 may generally be of any shape, such as circular, triangular, or multi-sided. Dimples 104 may be of uniform shape and size, or the dimple pattern may be made up of two or more different types of dimples having (for example) different sizes or different shapes. At least one land area 106 is a part of the cover layer that separates at least two dimples 104 and that is not indented or otherwise part of a dimple. Generally, land area 106 is the “ridge” or “fret” between adjoining dimples 104. Golf ball 100 may include one continuous land area 106 across the entire cover layer, as is shown in
As shown in
After the selective treatment, cover layer 200 generally includes a first portion having a first hardness, and a second portion having a second hardness. The first portion generally includes those sections 204 of cover layer 200 having at least one dimple 104 thereon. The first portion may include all sections 204 of cover layer 200 having dimples 104 thereon, or the first portion may include some of the sections 204 but not others. In other words, the first portion as a whole may include all of the dimples 104 thereon, or a subset of fewer than all of the plurality of dimples 104 thereon. Generally, the first portion of cover layer 200 can be made up of any number and arrangement of the sections 204. Similarly, the second portion of cover layer 200 generally includes those sections 208 having at least a part of at least one land area 108 thereon. The second portion may also be made up of all sections 208, or fewer than all of the sections 208. In other words, the second portion as a whole may include the entirety of all of the land area(s) thereon, or may include less than the entirety of all of the land area(s) thereon.
Either of the first or the second portion may extend through the entire cross-sectional thickness of the cover layer 200, as shown in
Each of the first portion and the second portions are non-overlapping portions of a continuous cover layer material. Namely, as shown in
The first hardness, associated with the first portion of cover layer 200, is higher than the second hardness, associated with the second portion of cover layer 200. Accordingly, the portions of cover layer 200 associated with dimples 104 are generally relatively hard, while the portions of cover layer 200 associated with land areas 108 are generally relatively soft. The degree of difference in hardness between the first portion and the second portion may be any non-trivial difference in hardness. In certain embodiments, the hardness of the first portion may be at least about 3 units on the Shore D scale harder than the hardness of the second portion. In other embodiments, the first potion may be at least about 5 units on the Shore D scale harder than the second portion.
Generally, the present disclosure encompasses two or more zones of differing hardness of the cover layer. For example, a golf ball may have three zones of hardness. In such an embodiment, cover layer 200 includes a third portion. The first portion, the second portion, and the third portion are all non-overlapping portions of the continuous cover layer material.
For example, a second embodiment of a dimple pattern that may be used in conjunction with the present disclosure is shown in
This cover layer 200 as shown in
Cover layer 200 is generally made of any material that can change in hardness in response to a selective treatment. In particular embodiments where the selective treatment comprises heating, cover layer 200 may comprise a phase transition material as described in U.S. Patent Application Publication No. 2008/0081710 (hereinafter referred to as “the '710 Publication”), the disclosure of which is hereby incorporated in its entirety. Specifically, the phase transition material described in the '710 Publication is an acid copolymer that comprises copolymerized residues of at least one alpha olefin having from two to six carbon atoms and copolymerized residues of at least one α, β-ethylenically unsaturated carboxylic acid having from 3 to 8 carbon atoms.
As described in the '710 Publication, this phase transition material changes hardness in response to heating. Specifically, heat energy decreases the hardness by disrupting the material's secondary crystal structure. As is generally known in the arts of polymer science, the hardness of a semi-crystalline polymer material can be proportional to the degree of crystallinity of the polymer material. The degree of crystallinity is the amount of the material that is in a crystalline phase, as compared to the amount of the material that is in an amorphous phase. The crystalline phase is generally harder than the amorphous phase, due to the close-packing crystal structure of the polymer molecules therein.
Therefore, golf ball 100 may be heated in a heating device 300 as shown in
Specifically, as shown in
Although
In another embodiment, the cover layer 220 may comprise a semi-crystalline thermoplastic material. Methods for changing the hardness of semi-crystalline thermoplastic materials are fully described in U.S. Pat. No. ______, currently U.S. patent application Ser. No. 12/690,493, entitled Methods and Systems for Customizing a Golf Ball, and filed on Jan. 20, 2010, the disclosure of which is hereby incorporated in its entirety.
Specifically, as is shown in
Heating element 306 or heating element 308, as used in the methods described above, may generally be any heating mechanism that is capable of selectively heating the desired portions of the cover layer. In a particular embodiment, as mentioned above and shown in
In particular,
In the embodiment shown in
As mentioned, portions 404 may be comprised of a first material, while portions 408 may be comprised of a second material. In embodiments, the first material may be a polyurethane material or an ionomer material, while the second material may also be a polyurethane material or an ionomer material, where the first material and the second material are different materials. For example, the first material may be a polyurethane while the second material is an ionomer. Alternatively, the first material may be an ionomer while the second material is a polyurethane.
Polyurethane materials are known to be used in golf ball construction. Generally, polyurethane polymers are formed from the reaction of a long-chain polyol and a polyisocyanate. Polyurethane includes thermosetting urethane and thermoplastic polyurethanes. A wide range of polyurethane formulations are known to a person having ordinary skill in the art of golf ball manufacturing. Example representative polyurethane compositions are disclosed in: U.S. Pat. No. 6,392,002 to Wu, entitled “Urethane Golf Ball” and issued on May 21, 2002; U.S. Pat. No. 6,835,793 to Yokota et al., entitled “Golf Ball having a Polyurethane Cover” and issued on Dec. 2, 2004; and U.S. Pat. No. 6,422,954 to Dewanjee, entitled “Golf Ball having a Polyurethane Cover” and issued on Jul. 23, 2002. The disclosures of these three U.S. patents are hereby incorporated by reference.
Ionomer materials are also known to be used in golf ball construction. Generally, ionomer polymers include any polymer formed from both an electrically neutral monomer and an ionized monomer. Ionomer polymers that are commonly used in golf ball construction are often formed from an short-chain alkene and an organic acid. Ionomer materials include the category of materials referred to as high acid ionomers, and includes the category of materials referred to as highly-neutralized polymers, among many others. Example representative ionomer materials are disclosed in: U.S. Pat. No. 5,994,472 to Egashira et al., entitled “Ionomer Covered Golf Ball” and issued on Nov. 20, 1999; U.S. Pat. No. 5,873,796 to Cavallaro et al., entitled “Multi-Layer Golf Ball Comprising a Cover of Ionomer Blends” and issued on Feb. 23, 1999; and U.S. Pat. No. 6,433,094 to Nesbitt et al., entitled “Golf Ball Covers Containing High Acid Ionomers” and issued on Aug. 13, 2002. The disclosures of these three U.S. patents are hereby incorporated by reference. In particular, commonly used ionomer materials include the Surlyn® line of materials commercially available from E.I. du Pont de Nemours and Company.
Polyurethane materials and ionomer materials may have different physical properties, and this difference in physical properties may be used in the construction of the present golf ball to achieve desired play characteristics. In particular, polyurethane materials and ionomer materials may have different hardnesses. Hardness is generally measure in accordance with ASTM D-2240, and is given in units of Shore D unless otherwise noted.
Generally, polyurethane materials used in golf ball construction may have a hardness of from about 20 to about 60 Shore D. Ionomer materials used in golf ball construction may have a hardness of from about 40 to about 80 Shore D. Generally, the two materials used should have different hardness values. Typically, in some embodiments, polyurethane materials used in golf ball construction have a lower hardness than ionomer materials used in golf ball construction.
The degree of difference in hardness between the polyurethane material and the ionomer material may be any non-trivial difference in hardness. In certain embodiments, the hardness of the ionomer material may be at least about 3 units on the Shore D scale harder than the hardness of the polyurethane material. In other embodiments, the ionomer material may be at least about 5 units on the Shore D scale harder than the polyurethane material, or at least about 10 units, or at least about 15 units.
Portions 604 and portions 608 may be laterally adjacent to each other at boundary 670. In the particular embodiment shown in
In the embodiment shown in
Generally, in each of
In different embodiments than those discussed variously above, the difference in hardness between the dimples and the land areas can be achieved through the use of a coating material.
In the embodiment shown in
When coating material 810 is coated on cover layer 802 having pockets 812 therein, coating material 810 fills the pockets 812 as well as coats the surface of cover layer 802 with a top section 814 of coating material 810. The top section 814 of coating material 810 may be left in place on the second pattern on top of land areas 806, if desired, or may be removed to leave coating material 810 only in the pockets 812.
In these embodiments including pockets 812 and/or pockets 816, generally, the coating material may be used to change the hardness of the second pattern in accordance with this disclosure, without changing the diameter or aerodynamic performance of the golf ball. Therefore a wider range of golf ball designs may be used in accordance with the present disclosure, without the need to redesign the physical structure of the golf ball or sacrifice advantageous aerodynamic properties.
The coating material may generally be selected in accordance with the desired hardness. In embodiments, such as are shown in
In other embodiments, the coating material may be polyurethane or an ionomer in particular. For example, cover layer 802 may be comprised of a polyurethane or an ionomer, while the coating material may be comprised of the other of a polyurethane or an ionomer. In the embodiment of
Similarly, in the embodiment of
Additionally, the coating material may be a metal plating. Nearly any typical metal may be used, as most metals have a hardness at conventional temperatures that is higher than polymer materials conventionally used to form golf ball cover layers. Exemplary metals that may be used as the coating material include aluminum, steel, tungsten, titanium, magnesium, and iron alloys, among a variety of others. The metal coating material may be selected based on hardness, workability, and cost effectiveness.
Next, method 900 of manufacturing the golf ball may take either of two general routes. In a first step 906 of a first route, the entire cover layer is coated with the coating mater. The coating may be a physical coating step, such as by brushing, dipping, spraying or other physical application means. Alternatively, the coating may be a chemical coating step, such as chemical vapor deposition (CVD), plasma spray coating, or other chemical application means. The coating material is then selectively removed in step 908, such that the coating layer remains only on either of the first or second pattern, as desired. The removal of the coating material may be a physical grinding away of the coating, or may be a chemical removal such as by chemical etching using a mask to protect selected coated areas to prevent the removal of selected coated areas.
Alternatively, in step 910 a mask may be applied over the golf ball. The mask may be a physical mask having a pattern of holes corresponding to either of the first pattern or the second pattern. The coating material is then 912 applied on top of the mask, after which 914 the mask is removed, leaving the coating material on only the pattern corresponding to the holes in the mask.
Finally, if the golf ball underwent step 904 to create pockets, the surface portion of the coating material 814 may be removed in step 916. This step leaves the coating material in only the pockets, and not otherwise substantially overlapping the surface of the cover layer.
For purposes of this disclosure, the terms “compressible,” “compressibility,” and the like refer to the amount deformation exhibited by an object when compressed under a predetermined set of loading parameters. As used in the present disclosure, compressibility shall refer to compression deformation, which is the deformation amount (in millimeters) of an object when compressed by a force, specifically, the deformation of the object when the compression force is increased from 10 kg to 130 kg. The deformation amount of the object under the force of 10 kg is subtracted from the deformation amount of the object under the force of 130 kg to obtain the compression deformation value of the object. While compressibility (and compression deformation) is a parameter that may be measured for entire golf balls, compressibility can also be measured for individual components of golf balls. In the present disclosure, compressibility of a golf ball groove material is measured and discussed in detail.
As mentioned above, these embodiments may be applicable to golf balls having any internal structural configuration.
Cover layer 1105 may be formed of a relatively soft but durable material. For example, cover layer 1105 may be formed of a material that compresses/flexes when struck by a golf club, in order to provide spin of the ball and feel to the player. Although relatively soft, the material may also be durable, in order to withstand scuffing from the club and/or the golf course. Generally, the cover layer may be formed of either a polyurethane material or an ionomer material. Polyurethane materials and ionomer materials are discussed above, and are well known to a person having ordinary skill in the art.
In addition,
Outer core layer 1110 may be formed of a relatively firm and suitably resilient material. Outer core layer 1110 may be configured to provide a relatively high launch angle and a relatively low spin rate when the ball is struck by a driver, and a relatively higher spin rate and increased control when struck with irons. This may provide distance off the tee with spin and control around the greens. Inner core layer 1115 may be formed of a relatively firm material in order to provide distance.
The thickness of the golf ball layers may be varied in order to achieve desired performance characteristics. In some embodiments, inner core layer 1115 may have a diameter in the range of about 19 mm to 30 mm. For example, in some embodiments, inner core layer 1115 may be spherical with a diameter 120 of approximately 24 mm to 28 mm.
As shown in
In the present disclosure and drawings, golf ball 1200 is described and illustrated as having four layers. In some embodiments, at least one additional layer may be added. For example, in some embodiments, a mantle layer may be added between outer core layer 1215 and inner cover layer 1210. In some embodiments, an intermediate cover layer may be inserted between inner cover layer 1210 and outer cover layer 1205. Further, in some embodiments, an intermediate core layer may be inserted between inner core layer 1220 and outer core layer 1215. Other layers may be added on either side of any disclosed layer as desired to achieve certain performance characteristics and/or attributes.
In some embodiments, golf ball 1200 may have a diameter of at least 42.67 mm (1.680 inches), in accordance with the Rules of Golf. For example, in some embodiments, golf ball 1200 may have a ball diameter between about 42.67 mm and about 42.9 mm, and may, in some embodiments, have a ball diameter of about 42.7 mm. Golf ball 1200 may have a ball weight between about 45 g and about 45.8 g and may, in some embodiments, have a ball weight of about 45.4 g.
The thickness of the layers of golf ball 1200 may be varied in order to achieve desired performance characteristics. In some embodiments, outer cover layer 1205 may have a thickness of approximately 0.5 mm to 2 mm. In addition, in some embodiments, inner cover layer 1210 may have a thickness of approximately 0.5 mm to 2 mm. In some embodiments, outer cover layer 1205 and/or inner cover layer 1210 may have a thickness of approximately 0.8 mm to 2 mm. In some embodiments, outer cover layer 1205 and/or inner cover layer 1210 may have a thickness of approximately 1 mm to 1.5 mm.
In some embodiments, outer core layer 1215 may have a thickness of at least about 5 mm. In some embodiments, inner core layer 1220 may be a sphere having a diameter 1225 in the range of approximately 21 mm to 30 mm. In some embodiments, diameter 1225 of inner core layer 1220 may be in the range of approximately 24 mm to 28 mm. For example, in some embodiments, diameter 1225 may be 24 mm. In other embodiments, diameter 1225 may be 28 mm.
In some embodiments, the inner core layer may be formed by any suitable process, such as injection molding or compression molding. Further the inner core layer may be formed of any suitable material, such as a thermoplastic material, for example. In some embodiments, suitable thermoplastic materials may include, for example, an ionomer resin, such as Surlyn®, produced by E. I. Dupont de Nemours and Company. In some embodiments, the inner core layer may be formed from a highly neutralized acid polymer composition. Exemplary highly neutralized acid polymer compositions suitable for forming the inner core layer may include, for example, HPF resins such as HPF1000, HPF2000, HPF AD1024, HPF AD1027, HPF AD1030, HPF AD1035, HPF AD1040, all produced by E. I. Dupont de Nemours and Company.
The acid polymer may be neutralized to 80% or higher, including up to 100%, with a suitable cation source, such as magnesium, sodium, zinc, or potassium. Suitable highly neutralized acid polymer compositions for use in forming the inner core layer may include a highly neutralized acid polymer composition and optionally additives, fillers, and/or melt flow modifiers.
Suitable additives and fillers may include, for example, blowing and foaming agents, optical brighteners, coloring agents, fluorescent agents, whitening agents, UV absorbers, light stabilizers, defoaming agents, processing aids, antioxidants, stabilizers, softening agents, fragrance components, plasticizers, impact modifiers, acid copolymer wax, surfactants. In some embodiments, the additives and fillers may include, for example, inorganic fillers, such as zinc oxide, titanium dioxide, tin oxide, calcium oxide, magnesium oxide, barium sulfate, zinc sulfate, calcium carbonate, zinc carbonate, barium carbonate, mica, talc, clay, silica, lead silicate, and other types of organic fillers. In some embodiments, the additives and fillers may include, for example, high specific gravity metal powder fillers, such as tungsten powder, molybdenum powder, and others. In some embodiments the additives and fillers may include regrind, that is, core material that is ground and recycled.
Any suitable melt flow modifiers may be included in the highly neutralized acid polymer composition. Exemplary suitable melt flow modifiers may include, for example, fatty acids and salts thereof, polyamides, polyesters, polyacrylates, polyurethanes, polyethers, polyureas, polyhydric alcohols, and combinations thereof.
The outer core layer may be formed by any suitable method, such as compression molding. Further, the outer core layer may be formed of any suitable material, such as a thermoset material. For example, in some embodiments, outer core layer 1215 may be formed by crosslinking a polybutadiene rubber composition. When other rubber is used in combination with a polybutadiene, polybutadiene may be included as a principal component. For example, a proportion of polybutadiene in the entire base rubber may be equal to or greater than 50% by weight and, in some embodiments, may be equal to or greater than 80% by weight. In some embodiments, outer core layer 215 may be formed of a polybutadiene rubber composition including a polybutadiene having a proportion of cis-1,4 bonds of equal to or greater than 60 mol %. For example, in some embodiments, the proportion may be equal to or greater than 80 mol %.
In some embodiments, cis-1,4-polybutadiene may be used as the base rubber and mixed with other ingredients. In some embodiments, the amount of cis-1,4-polybutadiene may be at least 50 parts by weight, based on 100 parts by weight of the rubber compound. Various additives may be added to the base rubber to form a compound. The additives may include a cross-linking agent and a filler. In some embodiments, the cross-linking agent may be zinc diacrylate, magnesium acrylate, zinc methacrylate, or magnesium methacrylate. In some embodiments, zinc diacrylate may provide advantageous resilience properties.
In some embodiments, the filler may include zinc oxide, barium sulfate, calcium carbonate, or magnesium carbonate. In some embodiments, zinc oxide may be selected for its advantageous properties. In some embodiments, the filler may be used to increase the specific gravity of the material. For example, metal powder, such as tungsten, may alternatively be used as a filler to achieve a desired specific gravity. In some embodiments, the specific gravity of outer core layer 215 may be in the range of about 1.05 g/cm{circumflex over (0)}3 to about 1.35 g/cm̂3.
In some embodiments, a polybutadiene synthesized using a rare earth element catalyst is preferred. Using this polybutadiene may provide golf ball 200 with increased resilience. Examples of rare earth element catalysts include lanthanum series rare earth element compound, organoaluminum compound, and almoxane and halogen containing compound. A lanthanum series rare earth element compound is preferred. Polybutadiene obtained by using lanthanum rare earth-based catalysts usually employ a combination of a lanthanum rare earth (atomic number of 57 to 71) compound, but particularly preferred is a neodymium compound.
In some embodiments, the polybutadiene rubber composition may comprise at least from about 0.5 parts by weight to about 5 parts by weight of a halogenated organosulfur compound. In some embodiments, the polybutadiene rubber composition may comprise at least from about 1 part by weight to about 4 parts by weight of a halogenated organosulfur compound. The halogenated organosulfur compound may be selected from the group consisting of pentachlorothiophenol; 2-chlorothiophenol; 3-chlorothiophenol; 4-chlorothiophenol; 2,3-chlorothiophenol; 2,4-chlorothiophenol; 3,4-chlorothiophenol; 3,5-chlorothiophenol; 2,3,4-chlorothiophenol; 3,4,5-chlorothiophenol; 2,3,4,5-tetrachlorothiophenol; 2,3,5,6-tetrachlorothiophenol; pentafluorothiophenol; 2-fluorothiophenol; 3-fluorothiophenol; 4-fluorothiophenol; 2,3-fluorothiophenol; 2,4-fluorothiophenol; 3,4-fluorothiophenol; 3,5-fluorothiophenol 2,3,4-fluorothiophenol; 3,4,5-fluorothiophenol; 2,3,4,5-tetrafluorothiophenol; 2,3,5,6-tetrafluorothiophenol; 4-chlorotetrafluorothiophenol; pentaiodothiophenol; 2-iodothiophenol; 3-iodothiophenol; 4-iodothiophenol; 2,3-iodothiophenol; 2,4-iodothiophenol; 3,4-iodothiophenol; 3,5-iodothiophenol; 2,3,4-iodothiophenol; 3,4,5-iodothiophenol; 2,3,4,5-tetraiodothiophenol; 2,3,5,6-tetraiodothiophenol; pentabromothiophenol; 2-bromothiophenol; 3-bromothiophenol 4-bromothiophenol; 2,3-bromothiophenol; 2,4-bromothiophenol; 3,4-bromothiophenol; 3,5-bromothiophenol; 2,3,4-bromothiophenol; 3,4,5-bromothiophenol; 2,3,4,5-tetrabromothiophenol; 2,3,5,6-tetrabromothiophenol; and their zinc salts, the metal salts thereof and mixtures thereof.
One or more cover layers may be molded to enclose the outer core layer. Generally, the cover layers may be formed of any suitable materials. For example, in some embodiments, cover layers may be formed from thermoplastic or thermoset materials. In some embodiments, inner cover layer 1210 and/or outer cover layer 1205 may be made from a thermoplastic material including at least one of an ionomer resin, a highly neutralized acid polymer composition, a polyamide resin, a polyester resin, and a polyurethane resin. In some embodiments, inner cover layer 1210 may be formed of the same type of material as outer cover layer 1205. In other embodiments, inner cover layer 1210 may be formed of a different type of material from outer cover layer 1205. In some embodiments, outer cover layer may be comprised of either polyurethane or ionomer, in particular. For example, the outer cover layer may be comprised of an ionomer such as Surlyn®.
The disclosed concepts may be implemented in golf balls having three-layer construction, four-layer construction, five-layer construction, or any other suitable configuration. Exemplary such concepts are discussed below.
In some embodiments, an exemplary disclosed golf ball may include features that provide increased spin and/or feel when struck. In order to provide such characteristics, the golf ball may be provided with one or more components formed of a material having an increased compressibility. That is, the material may deflect a greater amount when exposed to a given amount of force than a relatively less compressible material. In order to provide increased spin and/or feel, such compressible material may be disposed radially outward from the center of the ball, for example at or near the outer surface of the ball.
It is generally desirable for a golf ball to exhibit minimal spin when struck with a driver. Further, when a golf ball is struck with a club moving at a relatively high club head speed, such as a driver, the amount of deformation of the ball is significant, such that the properties of the core and other inner layers of the ball determine the playing characteristics, particularly distance. For these reasons, it may be desirable to provide a golf ball with a relatively hard and incompressible outer cover layer. An outer cover layer that is too compressible may be too “grippy” and thus produce more spin, even when struck with a driver. Further, a compressible outer cover layer would tend to absorb some of the energy of the impact with the club head and, therefore, reduce the distance achievable with the ball.
During short game play, however, it may be desirable for a golf ball to exhibit greater amounts of spin and feel. Greater amounts of spin facilitate greater control of the ball. During short game play, where club head speeds are relatively slower, the compressibility of the cover layers of the ball determine the playing characteristics, since the ball is not typically struck hard enough to compress the inner layers of the ball. Increased spin may be provided by a compressible outer cover layer material. Further, such a compressible outer cover layer may also provide improved feel of the ball when struck at relatively slow club head speeds. Thus, the desirability of having a compressible cover for short game play (e.g., playing with irons) may be in conflict with the desirability of having a relatively incompressible cover for long game play (e.g., hitting with a driver).
The present disclosure provides ball configurations, which implement both compressible and incompressible materials in the cover in order to produce a ball that has both good distance with low spin when struck with a driver, and increased spin and feel when struck with a short game club (e.g., irons, pitching wedge, sand wedge). In some embodiments, an exemplary disclosed golf ball may include one or more core layers and one or more cover layers. In some embodiments, an outermost cover layer, formed of a first material, having formed therein one or more grooves. For example, such grooves may include one or more channels, which may be formed in any suitable configuration. In some embodiments, for example, the outermost cover layer may include at least one spiral channel. In some embodiments, the cover layer may include circular grooves or circumferential grooves, which may be arranged in a grid about the outer surface of the ball.
In order to provide the increased spin and/or feel, a relatively compressible material may be disposed within the one or more grooves. Such material may have a compressibility that is less than the compressibility of the outermost cover layer material. In some embodiments, the outer cover layer material may constitute a substantial majority of the outer surface area of the golf ball and the outer surface of the material disposed in the grooves may constitute a substantial minority of the outer surface area of the golf ball. In some embodiments, the compressible material in the grooves, i.e. the groove material, may be selected from a polyurethane and an ionomer. Specifically, in some embodiments, the groove material may be polyurethane.
Similarly, in some embodiments, the outermost cover layer material may also be selected from a polyurethane and an ionomer, so long as the groove material and the cover material are different. For example, when the groove material is polyurethane the cover material may be an ionomer. However, in other embodiments, the groove material may be an ionomer while the cover material may be a polyurethane.
In some embodiments, the golf ball may include features that affect the aerodynamics of the ball. For example, in some embodiments, the outer surface of the material disposed in the grooves may extend beyond or may be recessed from the outer surface of the outermost cover layer. Therefore, the ball may include either bulges and/or recesses in the outer surface, which may have an effect on aerodynamics. In some embodiments the aerodynamic effect may be a reduction in drag coefficient, to improve distance and/or spin. In other embodiments, the effect may be an increase in drag coefficient, possibly in exchange for increased or decreased spin and/or control. In some embodiments, the orientation of the bulges and/or recesses may induce spin during flight. For example, a spiral arrangement of elongate bulges and/or recesses may cause a particular spin of the ball during flight.
For purposes of this disclosure and claims, the outer cover layer shall be referred to, in some cases, as the “outermost layer” of the golf ball. Similarly, the term “outermost surface area” of the golf ball is used in reference to the outer surface of the disclosed layers. It will be understood by those having ordinary skill in the art, however, that one or more finish coatings, including paint or other colorations, as well as one or more topcoats or clearcoats may be applied to an outer surface of the disclosed layers. These finish coatings have relatively insignificant thickness and, therefore, the outer surfaces of the disclosed layers are effectively the outermost surfaces of the golf ball, from a structural standpoint.
According to exemplary disclosed embodiments, spin and/or feel of the golf ball may be increased by the inclusion of a relatively compressible material at and/or near the outer surface of the outer cover layer. In some embodiments, a second material may be molded into the grooves of the outer cover layer, wherein the second material has a compressibility that is different than the compressibility of the outer cover layer material. For example, in some embodiments, a material that is more compressible than the outer cover layer material may be molded into the grooves. In other embodiments, the outer cover layer material may be more compressible than the material molded into the grooves. Although the material molded into the grooves (“groove material”) may be more or less compressible than the outer cover layer, for purposes of discussion, the embodiments discussed below, unless otherwise noted, will be described as having a groove material that is more compressible than the outer cover layer material.
In some embodiments, the outer surface of the groove material forms a portion of the outer surface of the ball. The surface area and thickness of the groove material may be factors in the extent to which the groove material affects the spin and feel of the ball. Generally, the greater the amount of exposed surface area and/or thickness of a compressible material, the greater the increases in spin and feel will be. A compressible material will exhibit more grip against the club face, much like a soft compound tire provides more road grip. Therefore the amount of compressible material surface area will affect the amount of grip the ball will have against the club face. This increase in grip provides more spin and feel when striking the ball. In addition, the thickness of the compressible material has a similar effect on grip, the thickness of the compressible material is related to the amount of compressible material present at the outer portion of the ball. The more compressible material present at the outer portion of the ball, the more the outer portion deforms when struck, even on short game strikes, which tend to be less forceful.
In order to limit the increase in spin provided by the inclusion of compressible groove material, the groove material may constitute a limited amount of the outer surface area of the ball. For example, in some embodiments, the outer surface of the outer cover layer may constitute a substantial majority of the overall surface area of the ball, and the outer surface of the groove material may constitute a substantial minority of the outer surface of the ball. In other embodiments, the outer surface of the groove material may constitute a substantial majority of the outer surface area of the ball, and the outer surface of the outer cover layer may constitute a substantial minority of the outer surface area of the ball. This configuration may be advantageous, for example, when the outer cover layer material is more compressible than the groove material.
In addition, the extent to which the groove material extends radially beyond the outer surface of the outer cover layer may also influence the spin and feel. In some embodiments, the groove material may partially fill the grooves, and thus, may have an outer surface that is recessed from the outer surface of the outer cover layer. In some embodiments, the groove material may completely fill the grooves. For example, in some embodiments, the outer surface of the groove material may be substantially flush with the outer surface of the outer cover layer. In some embodiments, the outer surface of the groove material may overfill the grooves, bulging out such that the outer surface of the groove material extends radially outward beyond the outer surface of the outer cover layer. Generally, the greater the distance of a groove material from the center of the ball (relative to the outer surface of the outer cover layer), the greater the increases in spin and feel. The further the groove material extends radially, the more surface area of the groove material will be engaged by the club face and the less surface area of the outer cover layer will be engaged by the club face, thus providing increased grip against the club face, resulting in increased spin and feel.
In some embodiments, outer cover layer 1325 may include a groove 1330 extending radially inward from an outer surface 1340 of outer cover layer 1325. In some embodiments, groove 1330 may have the form of an elongate channel. Such channels may have any suitable configuration, such as, for example a spiral arrangement, as shown in
Ball 1300 may include a groove material 1335 disposed within groove 1330. In some embodiments, groove material 1335 may have a compressibility that is different from the compressibility of the material from which outer cover layer 1325 is formed. In some embodiments, groove material 1335 may be more compressible than the material of outer cover layer 1325. In other embodiments, groove material 1335 may be less compressible than outer cover layer 1325. In particular embodiments, groove material 1335 may be selected from an ionomer and a polyurethane, while outer cover layer 1325 may be made of a material selected from an ionomer and a polyurethane, where outer cover layer 1325 is made from a different material than the groove material 1335. Accordingly, in a particular embodiment, outer cover layer 1325 may comprise an ionomer while groove material 1335 may comprise a polyurethane. Generally, as is known to a person having ordinary skill in the art, a polyurethane material may be more compressible than an ionomer material.
In some embodiments, groove material 1335 may have a hardness that is different than the hardness of outer cover layer 1325. For example, in some embodiments, groove material 1335 may have a hardness that is lower than the hardness of outer cover layer material 1325. Specifically, in one embodiment, groove material 1335 may comprise a polyurethane while outer cover layer 1325 may comprise an ionomer. As discussed variously above, a polyurethane may have a hardness that is less than a hardness of an ionomer.
In such embodiments, the harder outer cover layer material may provide durability to the outer surface 1345 of ball 1300, while the softer groove material 1335 may provide increased spin and/or feel. In other embodiments, groove material 1335 may have a hardness that is greater than the hardness of outer cover layer 1325.
The placement of the relatively compressible groove material 1335 in the cover region of ball 1300, radially displaced from the center of ball 1300, may enhance the increase in spin and/or feel provided by compressible groove material 1335. In addition, the compressible groove material 1335 may further enhance the increase in spin and/or feel in some embodiments where groove material 1335 extends radially outward beyond outer surface 1340 of outer cover layer 1325. For example, as shown in
The cross-sectional shape and the depth of groove 1330 within outer cover layer 1325 may have a number of possible configurations, as shown and discussed with respect to several exemplary disclosed embodiments. In one possible configuration shown in
The bulging of groove material 1335 beyond outer surface 1340 of outer cover layer 1325 may provide at least two benefits. First, the bulging groove material 1335 may provide ball 1300 with a different surface area when struck hard, such as with a driver, than when struck more easily, such as on short game strokes. When struck hard, the compressibility of groove material 1335 may allow groove material 1335 to deflect (compress) such that outer surface 1350 of groove material 1335 becomes substantially flush with outer surface 1340 of outer cover layer 1325. Thus, the surface area of outer surface 1345 of ball 1300 that contacts the club face when struck hard, will be constituted of all of outer surface 1340 and outer surface 1350 in the area of ball 1300 struck by the club face. In such situations, since the surface area of outer cover layer 1325 may constitute a substantial majority of outer surface 1345 of ball 1300, when ball 1300 is struck hard, more of the contact area between ball 1300 and the club face will be constituted by outer surface 1340 of outer cover layer 1325. Since outer cover layer 1325 may be less compressible than groove material 1335, this may be beneficial when driving the ball, because less spin is desired for drives.
When struck lightly, groove material 1335 may not compress completely. Accordingly, a larger proportion of the surface area of ball 1300 contacting the club face will be constituted by outer surface 1350 of groove material 1335. This may provide a grippier surface of ball 1300, thus producing more spin and providing increased feel.
A second benefit is that the bulging of groove material 1335 may provide an aerodynamic effect. The bulges of groove material 1335 may disrupt airflow around ball 1300, disrupting airflow in much the same way dimples do on a conventional golf ball. In addition, the pattern of bulging groove material 1335 may induce other aerodynamic effects. For example, a spiral arrangement, such as that shown in
In addition to aerodynamic effects provided by groove material 1335, ball 1300 may be provided with other aerodynamic effects by other structural features. For example, in some embodiments, ball 1300 may include dimples 1375 on outer surface 1340 of at least a portion of outer cover layer 1325. Alternatively, or additionally, in some embodiments, ball 1300 may have dimples in outer surface 1350 of groove material 1335 (not shown). Dimples 1375 may have any suitable configuration. In some embodiments, dimples 1375 may have an arrangement that is based on one or more dimple patterns known to those having ordinary skill in the art.
As shown in
Similar to the embodiment shown in
Groove 1430 may have side walls 1445. In some embodiments, side walls 1445 may be angled with respect to outer surface 1440 of outer cover layer 1425. For example, as shown in
Also unlike groove 1330 in
As illustrated in
As also illustrated in
In some embodiments, grooves may extend completely through the outer cover layer of the golf ball. In some such embodiments, the inner surface of the groove material may be in contact with the outer surface of the inner cover layer. In other embodiments, a portion of an underlying, inner cover layer may extend radially outward into (and in some cases through) the groove to form the groove material. These configurations may provide still further increases in manufacturability and/or durability of the assembly.
In some embodiments, groove material may be recessed from the outer surface of the outer cover layer. In some such embodiments, the outer cover layer may be formed of a more compressible material than the groove material. This configuration may operate on similar principles to embodiments, wherein a bulging groove material is more compressible than an outer cover layer into which it is molded. In some embodiments, this may provide a larger surface area of the ball formed of the more compressible material. Thus, such an embodiment could be implemented to provide even greater amounts of spin and/or feel.
In some embodiments, recessed groove material may be formed of a material that is more compressible than the outer cover layer. For example, the outer cover layer may be an ionomer when the groove material is a polyurethane. Such configurations may be implemented to provide a golf ball with a more durable outer surface. In a recessed groove material embodiment, contact between the outer surface of the groove material with clubs and the ground may be limited. By having a less compressible, and possibly harder, material disposed further radially outward than the more compressible groove material, and thus, exposed to more contact with the clubs and the ground, a more durable material may be subjected to a substantial majority of the abuse.
In addition to the benefits (discussed above) of adding a compressible material in the cover region of a golf ball having a recessed groove material, the recesses in the grooves may also provide an aerodynamic effect. As discussed above regarding the embodiment shown in
Groove material 1835 may have a compressibility, and/or hardness, that are different than outer cover layer 825. In some embodiments, outer cover layer 1825 may be more compressible than groove material 1835. For example, as mentioned above with respect to other embodiments, outer cover layer 1825 may comprise a polyurethane while groove material 1835 may comprise an ionomer. In other embodiments, groove material 1835 may be more compressible than outer cover layer 1825. For example, again as mentioned above with respect to other embodiments, outer cover layer 1825 may comprise an ionomer while groove material 1835 may comprise a polyurethane. In determining whether to utilize a more compressible material for outer cover layer 1825 or for groove material 1835, a ball designer may consider, as a factor, the desirability of performance characteristics provided by a more compressible material (e.g., spin, feel, control), and performance characteristics provided by a less compressible material (e.g., distance, durability). In order to achieve more compressible material characteristics, the more compressible material may be used to form outer cover layer 1825, which generally makes more contact with the club face. In order to achieve more incompressible material characteristics, the less compressible material may be used to form outer cover layer 1825.
Performance characteristics may also be determined by the relative surface areas of outer cover layer 1825 and groove material 1835 that make up the overall outer surface 1845 of ball 1800. For example, although a more compressible material may be utilized for recessed groove material 1835, the ball may be provided with more compressible material characteristics by making grooves 1830 wider and providing a higher ratio of groove material surface area to outer cover layer surface area.
Groove 1830 may have any suitable shape. As shown in
Golf ball 1800 may also include other surface features. For example, in some embodiments, ball 1800 may include dimples 1875 on at least a portion of outer surface 1840 of outer cover layer 1825 or in other portions of golf ball 1800.
In some embodiments, groove 2030 may have sidewalls 2055 that are angled relative to outer surface 2040 of outer cover layer 2025. In some embodiments, opposing sidewalls 2055 may be angled farther away from one another at outer surface 2040 of outer cover layer 2025, as shown in
As shown in
As also shown in
As shown in
Outer surfaces 2440 of outer cover layer 2425 and outer surfaces 2450 of groove material 2435 may constitute an outer surface 2445 of ball 2400. The size of grooves 2430 may vary and, accordingly, the ratio of surface area between outer surface 2440 and outer surface 2450 may also be varied to provide the desired performance characteristics.
Groove material 2435 may bulge beyond outer surface 2440 as indicated by a dimension 2460. In addition, grooves 2430 may include side walls 2455 that are angled with respect to outer surface 2440 of outer cover layer 2425.
As shown in
Golf ball 2400 may also include other surface features. For example, in some embodiments, ball 2400 may include dimples 2475 on at least a portion of outer surface 2440 of outer cover layer 2425 or in other portions of golf ball 2400.
As shown in
Outer surfaces 2540 of outer cover layer 2525 and outer surfaces 2550 of groove material 2535 may constitute an outer surface 2545 of ball 2500. The size of grooves 2530 may vary and, accordingly, the ratio of surface area between outer surface 2540 and outer surface 2550 may also be varied to provide the desired performance characteristics.
Outer surface 2550 of groove material 2535 may be recessed from outer surface 2540. In some embodiments, outer surfaces 2550 of groove material 2535 may be substantially planar, as shown in
As shown in
Golf ball 2500 may also include other surface features. For example, in some embodiments, ball 2500 may include dimples 2575 on at least a portion of outer surface 2540 of outer cover layer 2525 or in other portions of golf ball 2500.
As shown in
In some embodiments, outer cover layer 2625 may be formed as a grid, wherein the gridlines of the grid are formed by intersecting bands of material. For example, a first set of bands 2655 may intersect with a second set of bands 2660. Grid bands 2655 and 2660 may have any suitable configuration and orientation. As shown in
The openings in the outer cover layer grid may define grooves 2630. In some embodiments, as shown in
In some embodiments, groove material 2635 may be more compressible than outer cover layer 2625. In other embodiments, groove material 1635 may be less compressible than outer cover layer 2625. The advantages of each such configuration are discussed above in conjunction with other similar embodiments.
Golf ball 2600 may also include other surface features. For example, in some embodiments, ball 2600 may include dimples 2675 on at least a portion of outer surface 2640 of outer cover layer 2625 or in other portions of golf ball 2600.
The disclosed golf ball embodiments as shown in
The layers of a golf ball may be made using any of a number of molding processes, such as injection molding and compression molding. In some embodiments, outer layers may be molded on top of pre-molded inner layers. In some embodiments, an inner layer may be injection molded within a pre-molded outer shell.
In addition, pre-formed inner and/or outer layers may be supported during the process of co-molding an adjacent layer using a plurality of support pins. In some embodiments, the support pins may be a retractable part of the mold apparatus. In some embodiments, the support pins may be extensions of the pre-molded layer. For example, in some embodiments, support mold pins may be formed as part of a core layer and may meld with inner cover layer material during injection of the inner cover layer material. In such embodiments, the support pins may be formed of a material that is readily compatible with the material of the layer to be added. This compatibility may prevent or inhibit the formation of voids and/or delamination at the pin sites.
Use of support pins in molding processes are well-known in the art and, accordingly, one of ordinary skill would readily recognize support pin configurations that may be suitable for use in the methods described below.
An exemplary method of making a golf ball according to the present disclosure may include molding at least one core layer. In some embodiments the method may include molding multiple core layers, such as an inner core layer and an outer core layer. The formation of these core layers may be accomplished by injection molding and/or compression molding. Various techniques for forming golf ball core layers will be readily recognized by those having ordinary skill in the art.
In addition, the method may also include molding an outer cover layer radially outward of the core layer. The molding of this outer cover layer may be performed using injection molding or compression molding. In some embodiments, the method may include formation of an inner cover layer radially inward of the outer cover layer. In some embodiments, the inner cover layer may be formed first, and the outer cover layer may be molded afterward. In other embodiments, the outer cover layer may be pre-molded as a shell and then the inner cover layer may be injection molded under the pre-molded shell between the outer cover layer and the core layers. In some embodiments, the shell may be formed as two hemispherical shells, in order to enable a pre-molded core to be placed inside the shell before injecting the inner cover layer material.
The method may further include injecting a groove material 2735 through gates 2720 into the cavity within mold 2700 where it may flow into the void under shell 2725. Groove material 2735 may further flow radially outward through grooves 2730 (which may be formed completely through outer cover layer shell 2725), into recesses 2715. Molding groove material 2735 in this manner may form the groove material from portions of inner cover layer material that extend radially outward into grooves 2730.
As noted above, the groove material 2735 may be formed of a more or less compressible material than outer cover layer shell 2725.
Similar molds and methods may be used to form golf balls having other features of embodiments discussed above. For example, exemplary methods of making golf balls may include forming the grooves completely through the outer cover layer, and molding the groove material such that an inner surface of the groove material is in contact with an outer surface of the inner cover layer. Further, similar molds and methods may be used for form the grooves in any suitable size, shape, and arrangement, including those discussed above. For example, such molds and methods may be used to form grooves having angled side walls, rounded bottom surfaces, planar bottom surfaces, and other configurations discussed above. Also, similar molds and methods may be implemented to form the groove material in any of the various configurations discussed above.
Although not wishing to be bound by any particular theory of action, it is believed that golf balls according to the present disclosure achieve superior play characteristics due to the interaction between a golf club face and the golf ball as is shown in
In
In
In particular, as seen in the second zoomed-in section of
Thus, the present golf ball appears to be softer when hit with less force, but harder when hit with more force. Thereby, the present golf ball achieves improved play characteristics associated with harder cover layers (such as longer distance) during drives, while also achieving improved play characteristics associated with softer cover layers (such as higher spin) during short shots. Furthermore, golf balls made in accordance with this disclosure may also simultaneously achieve improved play characteristics that are unrelated to the hardness.
While various embodiments of the invention have been described, the description is intended to be exemplary, rather than limiting and it will be apparent to those of ordinary skill in the art that many more embodiments and implementations are possible that are within the scope of the invention. Accordingly, the invention is not to be restricted except in light of the attached claims and their equivalents. Also, various modifications and changes may be made within the scope of the attached claims.
This application is a Continuation-in-Part of co-pending application Ser. No. 13/004,829 filed Jan. 11, 2011, the disclosure of which is hereby incorporated by reference. This application is a Continuation-in-Part of co-pending application Ser. No. 12/690,761 filed Jan. 20, 2010, the disclosure of which is hereby incorporated by reference.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 12690761 | Jan 2010 | US |
| Child | 13004829 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 13004829 | Jan 2011 | US |
| Child | 13337989 | US |
