TWI600454B - Golf ball and method and golf ball mold for making the same - Google Patents

Description

Golf ball, and method for manufacturing golf ball and golf mold

The present disclosure generally relates to an injection mold for injection molded articles. In particular, the present disclosure relates to an injection mold for molding a golf ball.

Background of the invention

Golf is a sport that is increasingly popular both at the amateur level and at the professional level. A variety of techniques related to the manufacture and design of golf balls are known in the art. For example, one method of making a golf ball involves a layer of an injection molded golf ball. This method obtains a layer having a shape similar to a mold. In order to inject material into the mold, the mold contains a gate through which the hot material flows. As the material cools, the material hardens within the mold and between the molds surrounding the ball's equator with the gate and inside the gate. Thus, the molding layer of the golf ball includes a flash line around the equator of the ball and a gate runner with the gate set. In order to have a uniform finish on the outer surface of the golf ball, the overflow line and gate flow path are removed by grinding, buffing, and other processes. However, even after these removal processes, the gate marks at the locations where the gate runners are located are still visible. Gate mark defect rate can be checked by manual inspection or automated inspection 100 Or 1,000 golf balls to determine. According to predetermined criteria, if there are more than 4 gate marks or have a single deep gate mark, it is considered a defective ball. It would be advantageous to be able to mold a golf ball with reduced gate marking defects.

Summary of invention

A method of manufacturing a golf ball is disclosed. Golf balls produced by this method can have reduced gate defects. A method of making a golf ball can include injection molding a cover layer over a golf ball core and/or an inner cover layer. Molds for injection molding may have particular features that help reduce gate defects in golf balls.

In one aspect, the present disclosure provides a method of making a golf ball that can include the steps of providing a golf mold that includes a first mold cavity and a second mold cavity that is configured to mate with the first mold cavity. The first mold cavity may have a first mold chamber and a first parting edge disposed along a perimeter of the first mold chamber. The first gate may be disposed on the first mold edge. The first gate may provide a path for injecting the cover material into the first mold chamber and may have a first edge that forms a first round between the first edge and the first mold chamber. The method can include forming a golf ball core and placing the golf ball core between the first mold cavity and the second mold cavity. The method can also include mating the first mold cavity and the second mold cavity together. The method can include injecting a golf ball covering material into the first mold cavity and the second mold cavity. The step of injecting the golf covering material into the first mold cavity and the second mold cavity may include injecting the golf ball covering material through the gate of the first mold cavity. The first chamfer of the first gate may include a radius of curvature ranging from about 0.2 mm to about 0.5 mm. The path can have a generally rectangular cross section. The path can have a cross-sectional area ranging from about 0.3 mm ² to about 2 mm ² . The generally rectangular cross section may have a vertical height ranging from about 0.3 mm to about 1.5 mm. The cross section of the first gate may include at least one fillet. The at least one rounded corner may comprise a radius of curvature ranging from about 0.2 mm to about 0.5 mm.

The first gate may include a flat central surface joined by the first side surface and the second side surface disposed opposite the first side surface. The central surface, the first side surface, and the second side surface may collectively form a generally U-shaped cross section. The golf covering material may comprise a thermoplastic polyurethane. The golf covering material may comprise a crosslinked thermoplastic polyurethane elastomer. The method can also include forming an inner cover layer surrounding the core, wherein the inner cover layer has a surface Shore D hardness of at least 65. The step of forming the golf ball core may include injection molding the inner core layer and compression molding the outer core layer around the inner core layer. The inner core layer can comprise a highly neutralized acidic polymer composition. The second mold cavity can have a second mold chamber and a second mold edge disposed along a perimeter of the second mold chamber. The second gate may be disposed on the second mold edge. The second gate may provide a path for injecting the cover material into the second mold chamber and may have a second edge forming a second chamfer between the second edge and the second mold chamber. The first clamping edge may comprise 9 gates, the second clamping edge may comprise 9 gates, and when the first clamping edge is aligned with the second clamping edge, 18 paths may be arranged in the first Between the die edge and the second die edge.

The method can also include injecting a golf ball covering material having a flexural modulus of 200 psi to 1,000 psi into the first mold cavity and the second mold cavity. The first path may be offset from the second path in the vertical direction. Both the first clamping edge and the second clamping edge may have corresponding contoured surfaces such that the first cavity is capable of mating with the second cavity along the first clamping surface and the second clamping surface. The first gate may be aligned with a portion of the second mold edge to provide a first path for injecting the cover material into the first mold chamber when the first mold edge is mated with the second mold edge; The portion of the bi-mold edge that is aligned with the first gate may be concave such that the portion of the second clamping edge is outwardly curved away from the first gate. Forming the golf ball core can include compression molding the outer core layer around the inner core layer, and the outer core layer can have a surface Shore D hardness that is at least about 5 greater than the surface hardness of the inner core layer.

In another aspect, the present disclosure provides a method of making a golf ball. The method can include the step of providing a golf mold. The golf mold may include a first mold cavity having a first mold chamber and a first gate, the first mold chamber including a first mold edge disposed along a circumference of the first mold chamber, the first gate being disposed On the edge of the first clamping. The golf mold may further include a second mold cavity having a second mold chamber and a second gate, the second mold chamber including a second mold edge disposed along a circumference of the second mold chamber, the second gate being Arranged on the edge of the second mold. The second mold edge may have a shape corresponding to the first mold edge such that the first mold cavity may match the second mold cavity. The method can include forming a golf ball core. The golf ball core can comprise a thermoplastic material. The method can include placing a golf ball between the first mold cavity and the second mold cavity. The method can also include first clamping The edge matches the second clamping edge. When the two clamping edges are matched, the first gate can be aligned with a portion of the second clamping edge to provide a first path for injecting the covering material into the first mold cavity and the second mold cavity. Similarly, the second gate can be aligned with a portion of the first mold edge to provide a second path for injecting the cover material into the first mold cavity and the second mold cavity. The method can include injecting a golf ball covering material having a flexural modulus of 200 psi to 1,000 psi into the first mold cavity and the second mold cavity. The step of injecting the golf covering material into the first mold cavity and the second mold cavity may include injecting the golf ball covering material through the first gate and the second gate. The first path can have a generally rectangular cross section. The second path can have a generally rectangular cross section. The first path may be offset from the second path in the vertical direction.

In another aspect, the present disclosure provides a method of making a golf ball. The method can include the step of providing a golf mold. The golf mold may include a first mold cavity having a first mold chamber and a first gate, the first mold chamber including a first mold edge disposed along a circumference of the first mold chamber, the first gate being disposed On the edge of the first clamping. The golf mold may further include a second mold cavity having a second mold chamber and a second gate, the second mold chamber including a second mold edge disposed along a circumference of the second mold chamber, the second gate being Arranged on the edge of the second mold. Both the first clamping edge and the second clamping edge may have corresponding contoured surfaces such that the first cavity is capable of mating with the second cavity along the first clamping surface and the second clamping surface. The method can include forming a golf ball core. The method can include placing a golf ball between the first mold cavity and the second mold cavity. The method can also include mating the first mold cavity and the second mold cavity together. The method can include injecting a golf ball covering material into the first mold cavity and the second mold cavity. The first gate may be aligned with a portion of the second mold edge to provide a first path for injecting the cover material into the first mold cavity when the first mold edge is mated with the second mold edge. The portion of the second clamping edge that is aligned with the first gate may be concave such that a portion of the second clamping edge is outwardly curved away from the first gate. The step of forming a golf ball may include injection molding the inner core layer. The step of forming a golf ball may include compression molding the outer core layer around the inner core layer. The first path can have a generally rectangular cross section. The path can have a cross-sectional area ranging from about 0.3 mm ² to about 2 mm ² .

The generally rectangular cross section may have a vertical height ranging from about 0.3 mm to about 1.5 mm. The step of forming a golf ball may include compression molding the outer core layer around the inner core layer. The outer core layer can have a surface Shore D hardness that is at least about 5 greater than the surface hardness of the inner core layer. The first clamping edge may include 9 gates, the second clamping edge may include 9 gates, and when the first clamping edge is aligned with the second clamping edge, 18 paths may be arranged at the first Between the clamping edge and the second clamping edge. The first gate may have a first edge that forms a first chamfer between the first edge and the first mold chamber. The first chamfer may include a radius of curvature ranging from about 0.2 mm to about 0.5 mm.

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

100‧‧‧ cavity

102,702‧‧‧Mold room

104,704‧‧‧Protruding

106, 606‧‧ ‧ clamping edge

110,610‧‧‧ aperture

112,712‧‧‧ gate

208,708‧‧‧ middle surface

214,714‧‧‧ side surface

216,716‧‧‧ corner

218,718‧‧‧Side gate edge

220, 720‧‧‧ middle gate edge

600‧‧‧Second cavity

800, 1300 ‧ golf

802‧‧‧ dimple

804‧‧‧Circle

806‧‧‧gate runner

R ₁ , R ₂ ‧‧‧ radius of curvature

H _G , H _R ‧‧‧ Height

W _F , W _G ‧‧‧Width

L _S , L _E ‧‧‧ Length

D _B , D _M , D _P ‧‧‧ distance

1020, 1130, 1240‧‧‧Chamfered parts

1132‧‧‧ edge

1310‧‧‧ inner core layer

1320‧‧‧ outer core layer

1330‧‧‧ inner cover

1340‧‧‧ outer cover

1400‧‧‧ method

1402-1414‧‧‧Steps

The invention may be better understood with reference to the drawings and the description below. The components in the figures are not necessarily to scale, the Moreover, in the figures, like reference numerals refer to the

1 is a perspective view of a golf ball mold cavity according to an embodiment; FIG. 2 is an enlarged view of a portion of FIG. 1; FIG. 3 is an enlarged view of a portion of FIG. 1; Top plan view of a golf ball cavity; FIG. 5 is an enlarged view of a portion of FIG. 4; FIG. 6 is a golf ball cavity according to the embodiment shown in FIG. 1 pressed together with a correspondingly formed golf ball cavity Figure 7 is an enlarged view of the interior of the mold cavity mated together as shown in Figure 6; Figure 8 is a perspective view of a golf ball according to one embodiment; Figure 9 is a golf ball according to the embodiment of Figure 8 Figure 10 is an enlarged view of a portion of Figure 9; Figure 11 is a cross-sectional view of Figure 10; Figure 12 is a cross-sectional view of Figure 11; Figure 13 illustrates an exemplary fabrication made by the disclosed method Golf ball; and Figure 14 illustrates an exemplary embodiment of a method of making a golf ball.

Detailed description

A method of manufacturing a golf ball is disclosed. Golf balls produced by this method can have reduced gate defects. A golf ball typically includes a core that is substantially surrounded by one or more layers. For example, a golf ball may have a two-part construction with only a core and a cover layer, or a golf ball may have one or more intermediate layers between the core and the cover layer. A golf ball within the scope of the present disclosure may have a two-part construction or may have an additional intermediate layer between the core and the cover layer. The disclosed method can be used to form all types of golf balls.

The method can include injection molding the cover material around the core and/or the inner cover. The cover layer material may comprise a polymer such as a thermoplastic material, an elastomeric material or a thermoset material. In order to perform the disclosed method, a golf mold can be used. 1-7 illustrate a golf ball cavity 100 in accordance with an embodiment. 1 is a perspective view of a cavity 100 and FIG. 4 is a top plan view of a cavity 100. The mold cavity 100 can have a mold chamber 102 and a mold clamping edge 106. The mold chamber 102 may have an inverted hemispherical shape corresponding to a general shape of a half portion of the golf ball. The plurality of protrusions 104 may be dispersed throughout the surface of the mold chamber 102. The protrusion 104 of the mold chamber 102 may correspond to a dimple formed on the cover layer of the golf ball. The plurality of protrusions may generally be arranged such that the dimples are formed on the cover layer in any pattern, as may be known in the golf ball art. For example, the dimple pattern of a golf ball may generally be based on dividing a spherical surface of the ball into discrete polygonal surfaces. The edges of the surface can be joined to form a geometry that approximates the spherical surface of the golf ball. These geometries may include, for example, regular octahedral, regular icosahedral, and regular polyhedral arrangements. Once the geometry is selected, then The surface of the polyhedron can be filled with dimple patterns that can be repeated on the surface, respectively. The dimples can generally have any shape, such as circular, triangular or polygonal. The size of the dimples can vary. In one embodiment, the dimple diameter is between about 1 mm and about 5 mm. The depth of the dimples can also be varied based on the desired flight performance. In one embodiment, the dimple depth is between about 0.1 mm to about 0.3 mm. The dimples may have a uniform shape and size, or the dimple patterns may be composed of two or more different types of dimples having, for example, different sizes or different shapes. In certain embodiments, the mold cavity 100 can include a plurality of mold chambers to simultaneously mold a plurality of golf ball cover layers.

The mold cavity 100 can have a port 110 disposed on the mold edge 106 and a gate 112 of every other adjacent hole 110 on the mold edge 106. The gate 112 can be disposed between every other orifice 110 and the mold chamber 102. The orifice 110 and the gate 112 may provide a fluid path from the source of the cover material to the mold chamber 102.

In certain embodiments, a golf ball cover layer can be formed by placing a golf ball core between a plurality of golf ball molds. For example, Figures 6 and 7 illustrate how the mold cavity 100 can be pressed together with a second mold cavity 600 that is shaped to complement the mold cavity 100. The cavity 100 and the cavity 600 may together constitute a golf ball mold. In certain embodiments, a golf ball mold can include more than two cavities that collectively form a golf ball mold. For example, the mold cavity 100 can be divided into two mold cavities and/or the mold cavity 600 can be divided into two mold cavities. Thus, in such an embodiment, the golf ball mold will consist of three or four mold cavities. In certain embodiments, a core can be placed between the mold cavity 100 and the mold cavity 600. The cavity 600 may have a corresponding corresponding to the mold chamber 102, Die edge 106, orifice 110 and gate 112 mold chamber 702, mold edge 606, orifice 610 and gate 712. In embodiments where the mold cavity 100 has multiple mold chambers, the mold cavity 600 can have a plurality of corresponding mold chambers to simultaneously mold a plurality of golf ball cover layers. In embodiments where the golf mold is constructed of more than two mold cavities, the core can be placed between the mold cavities such that the mold cavity can surround the core.

The mold cavity 100 and the mold cavity 600 can be pressed together to enclose the core within the mold cavity. When the mold cavity and the mold cavity 600 are pressed together, the orifices can be aligned such that the orifices 110 and the orifices 610 together form a larger orifice through which the cover material can flow. Figure 7 is an enlarged view of the interior of the mold cavity mated together as shown in Figure 6. Figure 7 illustrates how the gate 112 can be aligned with a portion of the clamping edge 606 to form a generally rectangular opening. Similarly, the gate 712 can be aligned with a portion of the clamping edge 106 to form a generally rectangular opening. Each of the larger apertures can be in communication with a generally rectangular opening such that fluid can flow from the larger orifice through the generally rectangular opening into the mold chamber 102. In certain embodiments, a collapsible pin can be placed within the mold cavity to support the core such that the space can be retained between the core and the inner wall of the mold chamber. The cover layer material can be injected into the space between one or more of the apertures 110 and the apertures 610. The cover material can flow from the orifice to the mold chamber through one or more of the gate 112 and the gate 712. The cover material can fill the space between the core and the mold chamber. As the material cools, it can solidify and form a cover layer around the core.

Figure 2 is an enlarged plan view of a portion of Figure 1 including one of the gates. 3 is an enlarged view of a portion of FIG. 1 including another gate. Figure 5 is a diagram 4 includes an enlarged view of one of the apertures and a portion of one of the gates. In certain embodiments, the orifice 110 can be defined as a recessed region in which the width of the clamping edge 106 tapers toward the gate 112. The size and shape of the orifice 110 can be selected based on a variety of factors. For example, the size and shape of the orifice 110 can be selected based on the temperature of the mold cavity, the materials used in the injection molding process, and/or the size of the gate 112. The orifice 110 can be configured to direct material from the outer region of the mold edge 106 to the gate 112 and through the gate 112. In certain embodiments, the aperture 610 can have a different size and/or shape than the aperture 110. In certain embodiments, for example, as shown in FIGS. 6-7, the aperture 610 can have the same size and shape as the aperture 110.

Gate 112 can have a generally U-shaped cross section. In certain embodiments, the gate 112 can have two side surfaces 214 disposed opposite one another and a middle surface 208 disposed between the two side surfaces 214. In certain embodiments, the central surface 208 can join the side surfaces 214 at the corners 216. In certain embodiments, the side surface 214 can be substantially flat. The central surface 208 can be generally flat. In certain embodiments, the side surface 214 can contact the mold cavity 102 at the side gate edge 218. The central surface 208 can contact the mold chamber 102 at the middle gate edge 220. In certain embodiments, the side surface 214 and the middle surface 208 can each include a rounded or chamfered outer corner where the gate 112 contacts the mold chamber 102. For example, as shown in FIG. 5, the side edge of the gate portion 218 may be chamfered to have a radius of curvature of about 0.2mm to about 0.5mm R _1. In certain embodiments, the middle leading edge 220 may be chamfered to have from about 0.2mm to about 0.5mm radius of curvature R _1. , D _M vertical distance between the bottom-most central and central surface 208 of the leading edge 220 may be in the range shown in FIG. 7 from about 0.2mm to about 0.5mm. In certain embodiments, the corners 216 of the gate 112 can be chamfered to form rounded or chamfered interior corners. For example, as shown in FIG. 7, the rounded corner 216 may be formed having a radius of curvature R of from about 0.2mm to about 0.5mm _2. The chamfering of the gate corners and/or edges can help disperse the stresses in the covering material that have been placed in the mold during the injection.

In certain embodiments, as shown in FIG. 3, the gate 112 can have a height H _G ranging from about 0.3 mm to about 1.0 mm. In certain embodiments, as shown in FIG. 5, the gate 112 can have a width W _G along the side surface 214. W _G can range from about 1.0 mm to about 2.0 mm. In certain embodiments, the width shown in Figure 5, the gate 112 in FIG. 218 may be extended to a range of about 1.5mm to about 2.5mm final width W _F along the leading edge. In certain embodiments, the side surfaces 214 as shown in Figure 5 may have a length in the range of from about 0.5mm to about 1.5mm L _S. In certain embodiments, as shown in FIG. 5, the side gate edge 218 can have a length L _E ranging from about 0.2 mm to about 0.5 mm. The entire length of the gate 112 may include the sum of the length L _S and the length L _E .

In some embodiments, the gate can have a different size and/or shape than the gate 112. In certain embodiments, for example, as shown in FIG. 7, gate 712 can have the same size and shape as gate 112. Gate 712 can have a side surface 714 and a middle surface 708. The middle surface 708 can join the side surfaces 714 at the corners 716. In certain embodiments, the side surface 714 can contact the mold cavity 702 of the mold cavity 600 at the side gate edge 718. The middle surface 708 can contact the mold chamber 702 at the middle gate edge 720.

The size and shape of gate 112 and/or gate 712 can be selected based on a variety of factors. For example, the size and shape of the gate 112 and/or gate 712 can be selected based on the temperature of the mold cavity, the materials used in the injection molding process, and/or the size of the platform region disposed between the protrusions 104. In certain embodiments, the gates 112 and/or gates 712 can be configured to lie flat on a platform area that is disposed between the protrusions 104. In certain embodiments, the gates 112 and/or 712 can have a generally rectangular cross-section to provide a cross-section having a sufficient area to allow material to flow while maintaining the dimensions of the generally rectangular cross-section small enough to fit. On the platform area that is disposed between the protrusions 104 and/or the protrusions 704. For example, the height H _G can be selected to be small enough to fit between the protrusions 104. In order to provide a cross section having an area that is sufficiently large for the effective implant material, the width W _G and the width W _F may be selected to be large enough to compensate for the smaller height H _G . In certain embodiments, the length of the gate can be selected to be sufficiently long for the finishing station that is modified from the gate flow path of the golf ball after molding. In certain embodiments, the length of the gate can be selected to be short enough to prevent the material from cooling and hardening too quickly.

In certain embodiments, as shown in Figure 7, the clamping edge 106 can have a wavy surface and the clamping edge 606 can have a surface with a corresponding shape such that the two clamping edges can be mated together. Each waveform of the first clamping edge 106 and the clamping edge 606 may have a peak. As mentioned above, the gate 112 can be aligned with a portion of the clamping edge 606 to form a generally rectangular opening or path, and the gate 712 can be aligned with a portion of the clamping edge 106 to form a generally rectangular opening or path. . As shown in Figure 7, the portion of the clamping edge that is aligned with the gate may be concave such that the portion of the clamping edge is outwardly curved away from the gate. The generally rectangular opening may have a height H _R ranging from about 0.3 mm to about 1.5 mm or from 0.3 mm to 0.8 mm. The generally rectangular opening may have a cross-sectional area ranging from about 0.3 mm ² to about 2 mm ² . The waveform of the clamping edge 106 and/or the clamping edge 606 may be such that H _{R is} slightly greater than H _G . For example, in certain embodiments, H _R can be from about 0.01 mm to about 0.5 mm greater than H _G . When the mold cavity 100 and the mold cavity 600 are placed together, as shown in Figures 6 and 7, the gate 112 may face the first direction and the gate 712 may face the second direction opposite the first direction. By having the first portion of the gate on one of the cavities and the second portion of the gate on the other of the cavities, the projections can be spaced closer to each other near the edge of the clamping. In other words, this configuration can provide more flexibility when designing the protrusions.

The generally rectangular opening formed by gate 112 may be offset in the vertical direction from the generally rectangular opening formed by gate 712. The waveform of the clamping edge 106 and/or the clamping edge 606 may be such that the offset is less than the offset if the clamping edge is completely flat. The size and shape of the waveform can be selected based on a variety of factors. For example, the size and shape of the waveform may be selected based on the size and/or shape of the gate, the size and/or shape of the mold chamber, and/or the size, shape, and/or position of the protrusion. In certain embodiments, the size and/or shape of the waveform can be selected to be sufficiently small that the flash lines produced during the molding process are not difficult to remove. In certain embodiments, the distance D _B between the bottommost point of the middle gate edge 220 and the bottommost point of the middle gate edge 720 can range from about 0.1 mm to about 1.0 mm. In certain embodiments, H _R can be from about 0.01 mm to about 0.5 mm than D _B . In certain embodiments, the clamping edge peak between peaks 106 and clamping edge 606 a distance D _P can range from about 0.5mm to about 2.0mm in. In certain embodiments, the clamping edge peak between peaks 106 and clamping edge 606 a distance D _P can range from about 0.5mm to about 1.0mm in. In certain embodiments, D _P may be about 0.05mm to about 0.5mm than the sum of D _M and H _R.

Although Figures 1 and 4 show a mold cavity 100 having 18 orifices 110 and 9 gates 112, the number of orifices and/or gates can vary. For example, the mold cavity 100 can include from about 10 orifices to about 24 orifices and from about 5 gates to about 12 gates. The number of orifices and/or gates can be selected based on a variety of factors. For example, the number of orifices and/or gates can be selected based on the temperature of the mold cavity, the materials used in the injection molding process, and/or the dimensions of the mold cavity. Increasing the number of gates may allow the gate to have a smaller cross-sectional dimension, which may reduce the size of the gate flow path left by hardening of the material in the gate during injection molding. In addition, reducing the size of the cross-sectional dimension of the gate can result in higher pressure to inject material through the gate.

Table 1 shows the results of testing a test mold comprising a mold according to an embodiment prepared in accordance with the present disclosure and a mold of a comparative embodiment having different gate shapes and sizes. Comparative examples include test results from molds manufactured during development. Golf molds in accordance with the present disclosure include embodiments A and B, with gate details shown in Table 1. The molds of the comparative examples having different gate shapes and sizes included Comparative Examples C, D, E, and F, the gate details of which are shown in Table 1. In Table 1, "opening shape" means the shape of an opening created by a gate and an edge aligned with a gate when the golf ball mold is assembled. In Table 1, "total opening height" means the total height of the opening created by the gate and the edge aligned with the gate. "Chamfer radius" It means the radius of the chamfer disposed along the edge formed between the gate and the mold chamber of the mold. The mold was tested by using a mold to create a cover layer around a core or inner ball having a diameter of 40.5 mm. The covering material having the composition shown in Table 2 was injection molded at a temperature of about 215 ° C to 230 ° C using a conventional injection machine. The amount of material is shown in Table 2 in parts by weight (pbw) or weight percent. PTMEG is a polytetramethylene ether glycol having a number average molecular weight of 2,000. PTMEG is commercially available under the tradename TERATHANE® from INVISTA. BG is 1,4-butanediol and is commercially available from BASF Corporation and other suppliers. TMPMP is trimethylolpropane monoallyl ether commercially available from Perstorp Specialty Chemicals AB. DCP is dicumyl peroxide. MDI is diphenylmethane diisocyanate commercially available from Hunstman International LLC under the trade name Suprasec® 1100. The cover material was formed by mixing PTMEG, BG, TMPME, DCP, and MDI in the ratios indicated. Specifically, these materials were prepared by mixing the components with high agitation for 1 minute, starting at a temperature of about 70 ° C, followed by a 10 hour post-cure process at a temperature of about 100 ° C. The cured polyurethane elastomer is ground into small pieces.

For each mold, 1,000 balls were made. The defect rate of the gate mark listed in Table 1 was determined by manually inspecting 1,000 golf balls. According to predetermined criteria, if there are more than 4 gate marks or 1 deep gate mark, the ball is considered a defective ball. As indicated by the test data, the mold prepared according to the present disclosure has a gate mark defect rate lower than that of the mold of the comparative example.

8-12 illustrate an exemplary golf ball 800 as it appears after the mold cavity 100 and cavity 600 are used to mold a cover layer around the core. Figure 8 is a perspective view of a golf ball in accordance with one embodiment. The dimples 802 on the golf ball 800 may correspond to the protrusions 104 of the mold chamber 102 and the protrusions 704 of the mold chamber 702. Golf ball 800 can include a loop 804 and a gate runner 806. The circulation passage 804 can be formed as the molten material flows through the flow passage to the orifice 110 and the gate 112 during the molding process. Gate runner 806 may be a by-product formed by gate 112 and gate 712 during the molding process. Gate runner 806 It can have substantially the same size and shape as gate 112 and gate 712. In certain embodiments, the golf ball 800 can include a flash line (not shown) that is disposed around the mid-latitude line of the ball where the mold line 106 and the mold line 606 are in contact during molding.

After the cover layer is molded, in order to have a uniform finish on the outer surface of the golf ball, the loop runner 804, gate runner 806, and flash line can be removed by modification, grinding, buffing, and/or other processes. The golf ball 800 can then be subjected to surface modification work. For example, the golf ball 800 can be spray coated with a protective coating or a coating that imparts aerodynamic properties to the golf ball 800. These coating materials can be liquid when they are applied to the ball. The ball 800 may be static or may be rotating before, during, and/or after the coating material is applied to the golf ball 800. The golf ball 800 can also be subjected to a surface treatment and/or stamping process before the protective coating is applied to the surface of the ball.

Figure 9 is a top plan view of a golf ball in accordance with the embodiment of Figure 8. Figure 10 is an enlarged plan view of a portion of Figure 9. The gate runner 806 can have a chamfered portion 1020 that forms a rounded corner where the gate runner 806 contacts the golf ball 800. The chamfered portion 1020 can be formed by the side gate edge 218 during molding. Figure 11 is a cross-sectional view of Figure 10. The gate runner 806 can have a chamfered portion 1130 that forms a rounded corner where the gate runner 806 contacts the golf ball 800. The chamfered portion 1130 can be formed by the central gate edge 218 during molding. The gate runner 806 can have an edge 1132 where the gate runner 806 contacts the golf ball 800 on the side opposite the chamfered portion 1130. In some embodiments, the portion of the clamping edge 606 opposite the gate 112 can be adjacent the mold cavity 602 with the middle gate edge 220 can be chamfered in the same manner as chamfering. Similarly, the portion of the clamping edge 106 opposite the gate 712 can be chamfered adjacent the mold cavity 102 in the same manner as the middle gate edge 720 can be chamfered. In such an embodiment, the edge 1132 can be chamfered in the same manner as the chamfered portion 1130.

Figure 12 is a cross-sectional view of Figure 11 . Gate runner 806 can include a chamfered portion 1240 that forms a chamfer. The chamfered portion 1020 can be formed by the corner 216 of the gate 112 and/or the corner 716 of the gate 712 during molding.

FIG. 13 illustrates an exemplary golf ball 1300 made by the disclosed method, which is described in detail below. The golf ball 1300 can include an inner core layer 1310, an outer core layer 1320 that substantially surrounds the inner core layer 1310, an inner cover layer 1330 that substantially surrounds the outer core layer 1320, and an outer cover layer 1340 that substantially surrounds the inner cover layer 1330.

As used herein, unless otherwise stated, compression set, hardness, COR, flexural modulus, and Vicat softening temperature are measured as follows:

A. Compression Deformation: Compression Deformation In this paper, the amount of deformation of the ball under the force is indicated; specifically, when the force is increased from 10kg to 130kg, the deformation of the ball under the force of 130kg minus the force of the ball at 10kg The amount of deformation below becomes the compression deformation value of the ball.

B. Hardness: The hardness of the golf ball layer is typically measured according to ASTM D-2240, but is measured on the platform area of the curved surface of the molded ball.

C. Method of Measuring COR: The golf ball used for testing was launched by an air cannon at an initial speed of 40/sec, and the speed monitoring device was positioned at a distance of 0.6 to 0.9 meters above the cannon. When the hit is positioned about 1.2 meters from the air cannon When the steel plate is used, the golf ball bounces back through the speed monitoring device. The return speed divided by the initial speed is COR.

D. Flexural modulus: measured according to ASTM D-790.

E. Vicat softening temperature: measured according to ASTM D-1525.

In certain embodiments, the cover layer 1310 can comprise a thermoplastic polyurethane. The thermoplastic polyurethane can be a crosslinked thermoplastic polyurethane elastomer. The crosslinked thermoplastic polyurethane elastomer may comprise crosslinks formed from pendant allyl ether groups. In certain embodiments, the crosslinked thermoplastic polyurethane elastomer can be a product that reacts an organic isocyanate with a mixture of the following reactants: (a) an unsaturated diol chain extender having the formula wherein the unsaturated diol is unsaturated The chain extender has two primary alcoholic hydroxyl groups and at least one pendant side of allyl ether.

Wherein R is an alkyl group with or without a modifying functional group, and x and y are integers from 1 to 4; (b) a secondary chain extender having at least two reactive sites with isocyanate and having a ratio of less than about 450 a molecular weight; (c) a long chain polyol having a molecular weight ranging from about 500 to about 4,000; and (d) a sufficient amount of a free radical initiator to be capable of generating a crosslinked structure in the hard segment by free radical initiation. Free radicals.

The unsaturated diol chain extender can generally be any diol having at least one unsaturated bond. As is generally known, the unsaturated bond can be in two carbonogens A double bond between the two (such as in an olefin) or a triple bond (as in an alkyne). In certain embodiments, the unsaturated diol chain extender can have two primary alcohol groups. The presence of two primary alcohol groups can result in favorable reaction kinetics such that the crosslinked thermoplastic polyurethane can be formed in a "one-step" continuous process that is easily controlled.

In certain embodiments, the unsaturated diol chain extender can have two primary alcohol hydroxyl groups and at least one allyl ether pendant group, thereby having the formula:

Wherein R is an alkyl group with or without a modifying functional group, and x and y are integers of 1 to 4. In certain embodiments, x and y can both have values of 1, 2, 3 or 4. In other embodiments, x and y can each have a different value between 1 and 4.

In certain embodiments, the unsaturated diol chain extender can be trimethylolpropane monoallyl ether ("TMPME"). TMPME may also be referred to as "trimethylolpropane monoallyl ether", "trimethylolpropane monoallyl ether" or "trimethylolpropane monoallyl ether". TMPME has a CAS number 682-11-1. TMPME may also be referred to as 1,3-propanediol, 2-ethyl-2-[(2-propen-1-yloxy)methyl] or 2-allyloxymethyl-2-ethyl -1,3-propanediol. TMPME is commercially available from Perstorp Specialty Chemicals AB.

The outer cover 1340 can have a surface Shore D hardness ranging from about 45 to about 60 or 45 to 55. The outer cover 1340 can have a flexural modulus ranging from about 200 psi to about 1,000 psi.

In certain embodiments, the inner cover 1330 can comprise a thermoplastic material material. The thermoplastic material of the inner cover layer 1330 may include at least one of an ionomer resin, a highly neutralized acidic polymer composition, a polyamide resin, a polyurethane resin, a polyester resin, and combinations thereof.

In certain embodiments, the inner cover 1330 can have a thickness of less than about 2 millimeters. In certain embodiments, the inner cover 1330 can have a thickness of less than about 1.5 millimeters. In certain embodiments, the inner cover layer 1330 can have a thickness of less than about 1 millimeter. In certain embodiments, the inner cover 1330 can be relatively thin compared to the remaining layers of the golf ball 1300, however it can also have the highest surface Shore D hardness in all layers. In certain embodiments, the inner cover layer 1330 can have a surface Shore D hardness of at least about 65, as measured on a curved face. Additionally, inner cover 1330 can have a high flexural modulus ranging from about 60,000 psi to about 100,000 psi or from about 70,000 psi to about 85,000 psi. In certain embodiments, the inner cover layer 1330 can have a specific gravity ranging from about 1.05 g/mm ² to about 1.5 g/mm ² to produce a large moment of inertia.

In certain embodiments, the material comprising the outer core layer 1320 can be a thermoset rubber. The outer core layer 1320 can be fabricated by crosslinking a polybutadiene rubber composition. In certain embodiments, polybutadiene can be the most important component when other rubbers are used in combination with polybutadiene. For example, the proportion of polybutadiene in the entire base rubber may be equal to or greater than 50% by weight. In another embodiment, the proportion of polybutadiene in the overall base rubber may be equal to or greater than 80% by weight. In certain embodiments, the outer core layer 1320 can have a surface Shore D hardness ranging from about 45 to about 65 or from about 50 to about 60. In certain embodiments, the outer core layer 1320 can have a inner core layer The surface hardness of 1310 is at least about 5 or at least about 10 Shore D hardness. The outer core layer 1320 can have a thickness ranging from about 4 mm to about 9 mm.

The inner core layer 1310 can have a COR value ranging from about 0.79 to about 0.85. The inner core layer 1310 may have a first recovery factor, and the golf ball 1300 may have a second recovery coefficient, and the first recovery coefficient may be at least about 0.01 higher than the second recovery coefficient. Golf ball 1300 can have a recovery factor ranging from about 0.77 to about 0.81.

Inner core layer 1310 can comprise a thermoplastic material. For example, inner core layer 1310 can comprise a highly neutralized acidic polymer composition. The highly neutralized acidic polymer composition can have a Vicat softening temperature ranging from about 50 °C to about 60 °C. In certain embodiments, the highly neutralized acidic polymer composition can include HPF resins such as HPF 1000, HPF 2000, HPF AD 1027, HPF AD 1035, HPF AD 1040, all of which are manufactured by E. I. Dupont de Nemours and Company.

The inner core layer 1310 may have a diameter ranging from about 21 mm to about 30 mm. Inner core layer 1310 can have a Shore D hardness ranging from about 45 to about 55. In order to have a lower ball rotation rate, the inner core layer 1310 may have a compression set ranging from about 3 mm to 5 mm.

FIG. 14 illustrates an exemplary embodiment of a method 1400 of manufacturing a golf ball. Method 1400 can include the step 1402 of providing a golf mold consistent with the present disclosure. For example, in certain embodiments, a method of making a golf ball can include the steps of providing a golf mold (shown in Figures 1-7 and discussed above). In certain embodiments, step 1404 can include forming a golf ball and/or layer. As described above, in the present disclosure The golf ball within the scope of the content may have a two-part construction or may have an additional intermediate layer between the core and the cover layer. Thus, in certain embodiments, step 1404 can include forming only a single core. In other embodiments, step 1404 can include forming an inner core layer and an outer core layer. In certain embodiments, step 1404 can include forming an inner core layer, an outer core layer, an outer sheath layer, and/or one or more inner cover layers.

In certain embodiments, forming a single core or inner core layer can include injection molding the core material into a generally spherical shape. In certain embodiments, the outer core layer can be formed by compression molding the outer core material around the inner core layer. Suitable vulcanization conditions can include a vulcanization temperature between about 130 ° C and about 190 ° C and a vulcanization time between 5 and 20 minutes. In order to obtain the desired rubber crosslinked body for use as the outer core layer, the vulcanization temperature may be at least about 140 °C.

In certain embodiments, the vulcanization step can be divided into two stages: first, the outer core material can be placed in a mold that forms the outer core layer and subjected to initial vulcanization to produce a pair of semi-vulcanized hemispheres. Cup. The pre-manufactured inner core layer can then be placed in one of the hemispherical cups and can be covered by another hemispherical cup, in which case complete vulcanization can be carried out. The surface of the inner core layer may be roughened prior to placement in the interior of the hemispherical cup to enhance adhesion between the inner core layer and the outer core layer.

In certain embodiments, the inner core layer can be formed by injection molding the inner core material. In certain embodiments, the inner core surface may be pre-coated with or pre-treated with a binder prior to molding the outer core layer to enhance the durability of the golf ball and enable high rebound.

In certain embodiments, step 1406 can include putting a golf ball core And/or layers are placed between the mold cavities of the golf mold provided in step 1402. In certain embodiments, step 1406 can include placing a golf ball between two complementary mold cavities. In embodiments where a single mold cavity has multiple mold chambers, step 1406 can include placing a plurality of golf ball cores between respective mold chambers to simultaneously mold a plurality of golf ball cover layers. In embodiments where the golf mold is comprised of more than two mold cavities, the core can be placed between the mold cavities such that the mold cavity can enclose the core.

In certain embodiments, step 1408 can include mating the cavities together to enclose a mold chamber surrounding the golf ball core and/or the cover layer. In certain embodiments, step 1410 can include injecting a golf ball cover material into a gate of a mold cavity. In certain embodiments, step 1410 can include injecting a golf ball cover material into the orifices and gates of the mold cavity. In certain embodiments, the golf ball cover material being injected during step 1410 can comprise any of the materials discussed above.

In certain embodiments, step 1412 can include removing the molded golf ball from the golf mold. In certain embodiments, step 1414 can include removing excess golf covering material from the golf ball. For example, the golf ball may include a circulation channel and/or a gate flow path caused by the golf ball covering material remaining in the gate during the molding process and remaining between the edges of the clamping.

It will be understood that any of the steps disclosed above can be performed in any order. For example, step 1402 can be performed at the same time as step 1404. In another embodiment, step 1404 can be performed prior to step 1402.

Although various embodiments of the invention have been described, the specification The intent is intended to be illustrative, and not restrictive, and it is obvious to those skilled in the art that many more embodiments and implementations are possible within the scope of the invention. Accordingly, the invention is not to be limited, except in the scope of the appended claims and their equivalents. In addition, various modifications and changes can be made within the scope of the claimed invention.

100‧‧‧ cavity

102‧‧‧Mold room

104‧‧‧Protruding

106‧‧‧Clamping edge

110‧‧‧孔口

112‧‧‧ gate

Claims (24)

A method of manufacturing a golf ball that reduces a gate mark defect rate, comprising: providing a golf mold including a first mold cavity and a second mold cavity configured to match the first mold cavity, the first mold cavity having a a first mold chamber and a first mold edge disposed along a periphery of the first mold chamber, wherein a first gate is disposed along the first mold edge, and the second mold has a second a mold chamber and a second mold edge disposed along a periphery of the second mold chamber, wherein the first mold cavity and the second mold cavity are matched to the first mold edge and the second mold edge Wherein the first gate has a flat central surface connected by a first side surface and a second side surface disposed opposite the first side surface, and wherein the middle surface, the first side surface, and the first surface The two side surfaces collectively define a generally U-shaped cross section, the first gate providing a first path for injecting a cover material into the first mold chamber having a generally rectangular cross section and Having a first edge, the first edge forming the first edge a first chamfer between the edge and the first mold cavity, wherein the substantially rectangular cross section has the first side surface, the second side surface, and the middle surface as its three sides, and a portion of the second clamping edge of one of the sides, wherein the first chamfer comprises a range of from about 0.2 mm to about 0.5 mm a radius of curvature; forming a golf ball core; placing the golf ball core between the first mold cavity and the second mold cavity; matching the first mold cavity and the second mold cavity; and A golf covering material is injected into the first mold cavity and the second mold cavity. A method of manufacturing a golf ball according to claim 1, wherein a second gate is disposed along the second mold edge, wherein the second gate has a first side surface of a second gate and a flat central surface of a second gate to which the second side surface of the second gate opposite to the first gate surface of the second gate is opposite to the first gate, and the second gate intermediate surface, the second gate The first side surface of the mouth and the second side surface of the second gate collectively form a cross section of the substantially U-shaped second gate, and the first mold edge as the one side A portion collectively provides a generally rectangular path for injecting a cover material into the second mold chamber, wherein further the second gate has a second edge at the second edge and the second A second chamfer is formed between the mold chambers. A method of manufacturing a golf ball according to claim 1, wherein the step of injecting a golf ball covering material into the first cavity and the second cavity comprises injecting through the first gate of the first cavity The golf ball covers the material. A method of manufacturing a golf ball according to claim 1, wherein the first The gate or the cross section of the second gate includes at least one round. A method of manufacturing a golf ball according to claim 1, wherein the golf ball covering material comprises a thermoplastic polyurethane. A method of manufacturing a golf ball according to claim 1, wherein forming a golf ball core comprises injection molding an inner core layer and compression molding a core layer surrounding the inner core layer, wherein the inner core layer comprises a height neutralization Acidic polymer composition. A method of manufacturing a golf ball according to claim 1, wherein the path has a cross-sectional area ranging from about 0.3 mm ² to about 2 mm ² . A method of manufacturing a golf ball according to claim 1, wherein the substantially rectangular cross section has a vertical height ranging from about 0.3 mm to about 1.5 mm. A method of manufacturing a golf ball according to claim 4, wherein the at least one rounded corner may comprise a radius of curvature ranging from about 0.2 mm to about 0.5 mm. A method of manufacturing a golf ball according to claim 5, wherein the golf ball covering material comprises a crosslinked thermoplastic polyurethane elastomer. A method of manufacturing a golf ball according to claim 1, further comprising forming an inner cover layer surrounding the core, wherein the inner cover layer has a surface Shore D hardness of at least 65. A method of manufacturing a golf ball according to claim 2, wherein the golf ball mold includes nine substantially U-shaped gates along the first mold edge, wherein the nine gates and the second portion are combined The die edges collectively provide nine generally rectangular paths; and the golf mold along the The second clamping edge includes nine generally U-shaped gates, wherein the nine gates collectively provide nine generally rectangular paths in conjunction with a portion of the first clamping edge. A method of making a golf ball, comprising: providing a golf ball mold including a first mold cavity having a first mold cavity, including a first mold edge along a perimeter configuration of the first mold cavity, And a first gate having a substantially U-shaped cross section disposed along the first mold edge; the golf mold further comprising a second mold cavity having a second mold chamber, including along the a second mold edge of the periphery of the two mold chambers, and a second gate disposed along the second mold edge, wherein the second mold edge has a shape corresponding to the first mold edge Aligning the first mold cavity with the second mold cavity; forming a golf ball core, the golf ball core comprising a thermoplastic material; placing the golf ball core in the first mold cavity and the second mold cavity Matching the first clamping edge and the second clamping edge together such that the first gate is aligned with a portion of the second clamping edge to provide a first cross-section that is generally rectangular a path having one of the second clamping edges The first path as a side is used to inject a cover material into the first mold cavity and the second mold cavity, and the second gate is aligned with a portion of the first mold edge to provide a a second path for injecting a cover material into the first mold cavity and In the second mold cavity; and injecting a golf ball covering material having a flexural modulus of 200 psi to 1,000 psi into the first mold cavity and the second mold cavity. A method of manufacturing a golf ball according to claim 13, wherein injecting the covering material into the first mold cavity and the second mold cavity comprises injecting the golf ball covering material through the first gate and the second gate. A method of manufacturing a golf ball according to claim 13, wherein the second path has a substantially U-shaped cross section, the U-shaped shape when the first clamping edge matches the second clamping edge The cross section forms a path having a generally rectangular cross section, wherein the rectangular cross section has the first clamping edge as a side. A method of manufacturing a golf ball according to claim 13, wherein the first path is offset from the second path in a vertical direction. A method of manufacturing a golf ball for reducing a gate mark defect rate, comprising: providing a golf ball mold including a first mold cavity having a first mold chamber, including one of peripheral configurations along the first mold chamber a first mold clamping edge, and a first gate disposed along the first mold edge, and a second mold chamber, and a second mold edge of the peripheral configuration of the second mold chamber a second cavity, wherein the first gate has a first edge, and the first edge forms a first chamfer between the first edge and the first mold cavity, the first chamfer includes a range from a radius of curvature of from about 0.2 mm to about 0.5 mm; and wherein both the first clamping edge and the second clamping edge have Corresponding waveform surface, such that the first mold cavity can be matched with the second mold cavity along the first mold surface and the second mold surface, so that the first gate and the rectangular cross section are One portion of the second mold edge of the side provides a first path having a generally rectangular cross section for injecting a cover material into the first mold cavity having the first mold chamber; The golf mold further includes a second gate disposed along the second mold edge; forming a golf ball core; placing the golf ball between the first mold cavity and the second mold cavity; The first mold cavity and the second mold cavity are mated together; and a golf ball covering material is injected into the first mold cavity and the second mold cavity. A method of manufacturing a golf ball according to claim 17, wherein the first gate is aligned with a portion of the second mold edge for providing when the first mold edge is matched with the second mold edge a first path for injecting a cover material into the first mold chamber, and wherein a portion of the second mold edge aligned with the first gate is concave such that the second mold edge The portion is bent outwardly away from the first gate. A method of manufacturing a golf ball according to claim 17, wherein the path has a cross-sectional area ranging from about 0.3 mm ² to about 2 mm ² . A method of manufacturing a golf ball according to claim 17, wherein the general body The cross section above the rectangle has a vertical height ranging from about 0.3 mm to about 1.5 mm. The method of manufacturing a golf ball according to claim 17, wherein forming a golf ball core comprises compression molding a core layer surrounding the inner core layer, and the outer core layer has a surface hardness higher than the inner core layer by at least about 5 The surface Shore D hardness. A method of manufacturing a golf ball according to claim 18, wherein when the first cavity is matched with the second cavity, wherein the golf mold includes nine gates along the first clamping edge, wherein The nine gates collectively provide nine substantially rectangular paths along with a portion of the second mold edge; and the golf mold includes nine gates along the second mold edge, wherein the nine gates A generally rectangular path is provided in conjunction with a portion of the first clamping edge. A golf ball mold for use in the method of any one of claims 1 to 22, comprising a first mold cavity and a second mold cavity configured to match the first mold cavity, the first mold cavity Having a first mold chamber and a first mold edge disposed along a periphery of the first mold chamber, wherein a first gate is disposed along the first mold edge, the second mold cavity has a a second mold chamber and a second mold edge disposed along a periphery of the second mold chamber, wherein the first mold cavity and the second mold cavity are matched to the first mold edge and the second mold a die edge; wherein the first gate has a flat central surface connected by a first side surface and a second side surface disposed opposite the first side surface, and wherein the middle surface, the first side surface And the second side surface Forming a substantially U-shaped cross section, the first gate providing a first path having a substantially rectangular cross section for injecting a cover material into the first mold chamber and having a first An edge forming a first chamfer between the first edge and the first mold cavity, wherein the substantially rectangular cross section has the first side surface as its three sides, a second side surface, and the middle surface, and a portion of the second mold edge as a side thereof, wherein the first chamfer includes a radius of curvature ranging from about 0.2 mm to about 0.5 mm. A golf ball manufactured by the method described in any one of claims 1 to 22.