U.S. patent application number 11/198589 was filed with the patent office on 2005-12-22 for high compression multi-layer rim golf balls.
Invention is credited to Kennedy, Thomas J. III, Melanson, David M., Tzivanis, Michael J..
Application Number | 20050282659 11/198589 |
Document ID | / |
Family ID | 37727963 |
Filed Date | 2005-12-22 |
United States Patent
Application |
20050282659 |
Kind Code |
A1 |
Kennedy, Thomas J. III ; et
al. |
December 22, 2005 |
High compression multi-layer RIM golf balls
Abstract
Disclosed herein, in various embodiments, are multi-layer golf
balls. In particular, disclosed herein are high compression
multi-layer golf balls covered with relatively thin and/or hard
reaction injection molded (RIM) covers. The golf balls exhibit such
characteristics as enhanced distance, low driver spin, high initial
velocity, and good feel and playability characteristics.
Inventors: |
Kennedy, Thomas J. III;
(Wilbraham, MA) ; Tzivanis, Michael J.; (Chicopee,
MA) ; Melanson, David M.; (Northampton, MA) |
Correspondence
Address: |
MICHAEL A. CATANIA
CALLAWAY GOLF COMPANY
2180 RUTHERFORD ROAD
CARLSBAD
CA
92008-7328
US
|
Family ID: |
37727963 |
Appl. No.: |
11/198589 |
Filed: |
August 4, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11198589 |
Aug 4, 2005 |
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11152446 |
Jun 13, 2005 |
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11152446 |
Jun 13, 2005 |
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09877600 |
Jun 8, 2001 |
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6905424 |
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09877600 |
Jun 8, 2001 |
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09411690 |
Oct 1, 1999 |
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6290614 |
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09411690 |
Oct 1, 1999 |
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09040798 |
Mar 18, 1998 |
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6855073 |
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Current U.S.
Class: |
473/371 ;
473/378 |
Current CPC
Class: |
A63B 37/0031 20130101;
A63B 37/0033 20130101; C08G 18/4854 20130101; A63B 45/00 20130101;
C08G 18/6685 20130101; A63B 37/0087 20130101; C08G 18/10 20130101;
A63B 37/0022 20130101; C08L 75/04 20130101; A63B 37/0003 20130101;
A63B 37/0045 20130101; A63B 2209/00 20130101; C08G 2120/00
20130101; C08G 18/10 20130101; A63B 45/02 20130101; A63B 37/0043
20130101; A63B 37/0078 20130101; A63B 37/12 20130101 |
Class at
Publication: |
473/371 ;
473/378 |
International
Class: |
A63B 037/12 |
Claims
1. A multi-layer golf ball comprising: a core; an intermediate
layer; and, a reaction injection molded cover; wherein the golf
ball has an Instron compression of 0.0950 or less.
2. The multi-layer golf ball of claim 1, wherein the ball has an
Instron compression of 0.0920 or less.
3. The multi-layer golf ball of claim 1, wherein the cover of the
ball has a thickness of 0.050 inches or less.
4. The multi-layer golf ball of claim 1, wherein the cover of the
ball has a thickness of 0.025 inches or less.
5. The multi-layer golf ball of claim 1, wherein the cover of the
ball has a thickness of from about 0.012 inches to about 0.018
inches.
6. The multi-layer golf ball of claim 1, wherein the cover of the
ball has a Shore B hardness of from about 50 to about 100.
7. The multi-layer golf ball of claim 1 wherein the cover of the
ball has a Shore B hardness of from about 80 to about 95.
8. The golf ball of claim 1, wherein the reaction injection molded
cover is comprised of a PTMEG polyol, an MDI prepolymer and a DETDA
amine.
9. The golf ball of claim 1, wherein the mantle comprises an
ionomer or a blend of ionomers.
10. The golf ball of claim 9 where the ionomer or blend further
comprises a fatty acid or fatty acid metal salt.
11. The golf ball of claim 1, wherein the cover defines a plurality
of dimples along the outer surface, wherein at least one of the
dimples extends through the cover layer to the mantle layer.
12. The golf ball of claim 1, wherein the cover is coated with a
coating composition comprising a white pigment.
13. The golf ball of claim 1, wherein a marking indicia is applied
to the exterior surface of the ball.
14. The golf ball of claim 1, wherein said core is produced from a
core composition comprising an organic sulfur compound.
15. The golf ball of claim 14, wherein the organic sulfur compound
is PCTP or a metal salt thereof.
16. A multilayer golf ball, comprising: a molded rubber core; an
intermediate layer between the cover and the core that has a Shore
D hardness measurement of greater than 60; and a thermoset
polyurethane/polyurea reaction injection molded cover having a
thickness of from about 0.010 inches to about 0.050 inches; wherein
the ball has an Instron compression of from about 0.0750 to 0.1000
and a resilience of greater than 0.790.
17. The multi-layer golf ball of claim 16, wherein the ball has an
Instron compression from about 0.0800 to about 0.0950.
18. The multi-layer golf ball of claim 16, wherein the cover of the
ball has a thickness of 0.025 inches or less.
19. The multi-layer golf ball of claim 16, wherein the cover of the
ball has a thickness of from about 0.012 inches to about 0.018
inches.
20. The multi-layer golf ball of claim 16, wherein the cover of the
ball has a Shore B hardness of from about 80 to about 95.
21. The golf ball of claim 16, wherein the mantle comprises an
ionomer or a blend of ionomers.
22. The golf ball of claim 21 where the mantle comprises an ionomer
that is greater than 80% neutralized and further comprises 5 to 50%
fatty acid or fatty acid metal salt.
23. The golf ball of claim 16, wherein the cover defines a
plurality of dimples along the outer surface, wherein at least one
of the dimples extends through the cover layer to the mantle
layer.
24. The golf ball of claim 16, wherein the cover is coated with a
coating composition comprising a white pigment.
25. The golf ball of claim 16, wherein a marking indicia is applied
to the exterior surface of the ball.
26. The golf ball of claim 16, wherein said core is produced from a
core composition comprising an organic sulfur compound.
27. The golf ball of claim 26, wherein the organic sulfur compound
is PCTP or a metal salt thereof.
28. A multi-layer golf ball comprising: a thermoplastic or
thermoset core; an intermediate layer; and, a reaction injection
molded cover; wherein the golf ball has an Instron compression of
0.0950 or less.
29. The golf ball of claim 28, wherein the reaction injection
molded cover is comprised of a PTMEG polyol, an MDI prepolymer and
a DETDA amine.
30. The multi-layer ball of claim 28, wherein the ball has a
resilience (as measured by the coefficient of restitution) of at
least about 0.790.
31. The multi-layer golf ball of claim 28, wherein the ball has an
Instron compression of 0.0920 or less.
32. The multi-layer golf ball of claim 28, where the core is
comprised of a thermoplastic.
33. The multi-layer golf ball of claim 32, where the thermoplastic
core is comprised of an ionomer or ionomer blend in which one or
more of the ionomers is neutralized to 80% or more and further
comprises 5 to 50% of a fatty acid or fatty acid metal salt.
34. The golf ball of claim 28, wherein the cover defines a
plurality of dimples along the outer surface, wherein at least one
of the dimples extends through the cover layer to the mantle
layer.
35. The golf ball of claim 28, wherein the cover is coated with a
coating composition comprising a white pigment.
36. The golf ball of claim 28, wherein a marking indicia is applied
to the exterior surface of the ball.
37. The golf ball of claim 28, wherein said core is produced from a
core composition comprising an organic sulfur compound.
38. The golf ball of claim 37, wherein the organic sulfur compound
is PCTP or a metal salt thereof.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The Present Application is a continuation-in-part
application of U.S. patent application Ser. No. 11/152,446, filed
Jun. 13, 2005, which is a continuation application of U.S. patent
application Ser. No. 09/877,600, filed Jun. 8, 2001, now U.S. Pat.
No. 6,905,424, which is a continuation application of U.S. patent
application Ser. No. 09/411,690, filed Oct. 1, 1999, now U.S. Pat.
No. 6,290,614, which is a continuation-in-part application of U.S.
patent application Ser. No. 09/040,798, filed Mar. 18, 1998, now
U.S. Pat. No. 6,855,073.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present disclosure relates, in various embodiments, to
multi-layer golf balls having a reaction injection molded (RIM)
cover. In particular, the disclosure is directed to high
compression, multi-layer golf balls covered with a relatively thin
and/or hard RIM cover. The golf balls exhibit, among other things,
improved ball speed and distance. Methods of preparing such golf
balls are also disclosed.
[0004] 2. Description of the Related Art
[0005] Golf balls have been generally categorized into three
different groups. These groups are, namely, one-piece or unitary
balls, wound balls, and multi-piece solid balls.
[0006] A one-piece ball typically is formed from a solid mass of
moldable material, such as an elastomer, which has been cured to
develop the necessary degree of hardness, durability, etc.,
desired. The one-piece ball generally possesses the same overall
composition between the interior and exterior of the ball. One
piece balls are described, for example, in U.S. Pat. No. 3,313,545;
U.S. Pat. No. 3,373,123; and U.S. Pat. No. 3,384,612.
[0007] A wound ball has frequently been referred to as a
"three-piece ball" since it is produced by winding vulcanized
rubber thread under tension around a solid or semi-solid center to
form a wound core. The wound core is then enclosed in a single or
multi-layer covering of tough protective material. Until relatively
recently, the wound ball was generally desired by many skilled, low
handicap golfers due to a number of characteristics, i.e., feel,
playability, etc.
[0008] For example, the three-piece wound ball has been produced
utilizing a balata, or balata like, cover material which is
relatively soft and flexible. Upon impact, it compresses against
the surface of the club producing high spin. Consequently, the soft
and flexible balata covers along with wound cores provide an
experienced golfer with the ability to apply a spin to control the
ball in flight in order to produce a draw or a fade or a backspin
which causes the ball to "bite" or stop abruptly on contact with
the green. Moreover, the balata cover produces a soft "feel" to the
low handicap player. Such playability properties of workability,
feel, etc., are particularly important in short iron play and low
swing speeds and are exploited significantly by highly skilled
players.
[0009] However, a three-piece wound ball has several disadvantages
both from a manufacturing standpoint and a playability standpoint.
In this regard, a thread wound ball is relatively difficult to
manufacture due to the number of production steps required and the
careful control which must be exercised in each stage of
manufacture to achieve suitable roundness, velocity, rebound,
"click", "feel", and the like.
[0010] Additionally, a soft thread wound (three-piece) ball is not
well suited for use by the less skilled and/or high handicap golfer
who cannot intentionally control the spin of the ball. For example,
the unintentional application of side spin by a less skilled golfer
produces hooking or slicing. The side spin reduces the golfer's
control over the ball as well as reduces travel distance.
[0011] Similarly, despite all of the benefits of balata, balata
covered balls are easily "cut" and/or damaged if mishit.
Consequently, golf balls produced with balata or balata containing
cover compositions can exhibit a relatively short life span. As a
result of this negative property, balata and its synthetic
substitute, trans-polyisoprene, and resin blends, have been
essentially replaced as the cover materials of choice by golf ball
manufacturers by materials comprising ionomeric resins and other
elastomers such as polyurethanes.
[0012] Multi-piece solid golf balls, on the other hand, include a
solid resilient core and a cover having single or multiple layers
employing different types of material molded on the core. The core
can also include one or more layers. Additionally, one or more
intermediate, or mantle, layers can also be included between the
core and cover layer(s).
[0013] By utilizing different types of materials and different
construction combinations, multi-piece solid golf balls have now
been designed to match and/or surpass the beneficial properties
produced by three-piece wound balls. Additionally, the multi-piece
solid golf balls do not possess the manufacturing difficulties,
etc., that are associated with the three-piece wound balls.
[0014] As a result, a wide variety of multi-piece solid golf balls
are now commercially available to suit an individual player's game.
In essence, different types of balls have been, and are being,
specifically designed to suit various skill levels. Moreover,
improved golf balls are continually being produced by golf ball
manufacturers with technological advancements in materials and
manufacturing processes.
[0015] In the past, the molding processes used for forming the
cover and/or the intermediate or mantle layer of a golf ball
usually involved either compression molding or injection molding
techniques.
[0016] In compression molding, the golf ball core is inserted into
a central area of a two piece die and pre-sized sections of cover
material are placed in each half of the die, which then clamps
shut. The application of heat and pressure molds the cover material
about the core.
[0017] Polymeric materials, or blends thereof, have been used for
modern golf ball covers because different grades and combinations
offer certain levels of hardness, damage resistance when the ball
is struck with a club, and elasticity, thereby providing
responsiveness when hit. Some of these materials facilitate
processing by compression molding, yet disadvantages have also
arisen. These disadvantages include the presence of seams in the
cover, which occur where the pre-sized sections of cover material
are joined, and high process cycle times which are required to heat
the cover material and complete the molding process.
[0018] Injection molding of golf ball covers arose as a processing
technique to overcome some of the disadvantages of compression
molding. The process basically involves inserting a golf ball core
into a die, closing the die and forcing a heated, viscous polymeric
material into the die. The material is then cooled and the golf
ball is removed from the die. Injection molding is well-suited for
thermoplastic materials, but has generally limited applications
with some thermosetting polymers. However, several of these
thermosetting polymers often exhibit the hardness and elasticity
properties desired in golf ball cover construction.
[0019] Furthermore, some of the most promising thermosetting
materials are reactive, requiring two or more components to be
mixed and rapidly transferred into a die before a polymerization
reaction is complete. As a result, traditional injection molding
techniques do not provide proper processing when applied to these
materials.
[0020] Reaction injection molding ("RIM") is a processing technique
used specifically for certain reactive thermosetting polymers. By
"reactive" it is meant that the polymer is formed from two or more
components which react. Generally, the components, prior to
reacting, exhibit relatively low viscosities. The low viscosities
of the components allow the use of lower temperatures and pressures
than those utilized in traditional injection molding. In reaction
injection molding, the two or more components are combined and
react to produce the final polymerized material.
[0021] Due to the continuous importance of improving the properties
of a golf ball, it would be beneficial to make a multi-layer golf
ball, such as a RIM covered multi-layer golf ball, that exhibits
improved properties for certain golfers.
[0022] These and other non-limiting objects and features of the
disclosure will be apparent from the following description and from
the claims.
BRIEF SUMMARY OF THE INVENTION
[0023] Disclosed herein, in various embodiments, are multi-layer
golf balls. In particular, disclosed herein are high compression
multi-layer golf balls covered with relatively thin and/or hard
reaction injection molded (RIM) covers. The golf balls exhibit such
characteristics as enhanced distance, low driver spin, high initial
velocity, and good feel and playability characteristics.
[0024] It has been found that the distance property in multi-layer
RIM covered golf balls can be improved, especially at high club
head speeds, by increasing the hardness (compression) of the ball.
Additionally, in order to reduce spin off the tee and yet maintain
the higher spin desired around the green, a harder and/or thinner
polyurethane/polyurea RIM cover can be utilized. In this regard, it
has been found that this combination mitigates the "anvil" effect
generally produced when striking the ball as the club "pinches" the
cover between the club face and the harder mantle or core of the
ball. This produces, in part, lower spin and greater distance. The
preferred multi-layer golf balls of this disclosure comprise a high
compression core, a mantle layer, and a relatively thin and/or
hard, polyurethane/polyurea RIM cover. This results in an improved
RIM covered golf ball having increased distance with acceptable
spin and playability properties.
[0025] In the exemplary embodiments, the core comprises a high
cis-polybutadiene crosslinked with a difunctional acrylate. In
further embodiments, the polybutadiene is a mid to high Mooney
viscosity polybutadiene or blends thereof. In other embodiments,
the solid core further comprises a peptizer to further increase the
resilience of the core. This results in a harder, high velocity
core, having a compression (Instron) of greater (softer) than
0.0750, including from about 0.0750 to about 0.130, and a
resilience (as measured indicated by the coefficient of
restitution) of from about 0.750 to about 0.830, including from
about 0.780 to about 0.810, from about 0.785 to about 0.805, and
from about 0.790 to about 0.805.
[0026] Additionally, in the exemplary embodiments, the mantle or
mantle layer comprises a relatively hard, high resilience material.
Examples of such materials include ionomers or ionomer blends.
Preferably, the ionomers are a blend of high acid ionomers,
including a blend of sodium, zinc and magnesium high acid ionomers,
among others. These thermoplastic materials produce a relatively
hard, high compression mantle layer with high resilience having a
thickness of about 0.020 inches to about 0.090 inches. The mantle
has a Shore D hardness, as measured on the mantled core, of from
about 50 to about 90, including from about 60 to about 72, and from
about 67 to about 72, a compression (Instron) of from about 0.0600
to about 0.1250, including from about 0.0700 to about 0.1000, and
about 0.0900, and a resilience (as measured by the coefficient of
restitution) of from about 0.750 to about 0.830, including from
about 0.805 to about 0.815 and about 0.810.
[0027] Moreover, in the exemplary embodiments, the cover comprises
a thermoset polyurethane/polyurea RIM material. The cover has a
Shore B hardness as measured on the molded cover of from about 50
to about 100 including from about 70 to about 100 and about 80 to
about 100. Additionally, the cover has a thickness, when measured
from the inside surface to the top of the land areas, of from about
0.010 inches to about 0.050 inches, including from about 0.010
inches to about 0.025 inches, from about 0.014 inches to about
0.021 inches and from about 0.014 inches to about 0.016 inches. The
covered ball has a compression (Instron) of from about 0.0750 to
about 0.1000, including from about 0.0850 to about 0.0920 and from
about 0.0860 to about 0.0900. The resilience of the ball (as
measured by the coefficient of restitution) is from about 0.770 to
about 0.820, including from about 0.790 to about 0.816 and from
about 0.805 to about 0.816.
[0028] Other embodiments of the balls and/or the components thereof
are more particularly described below. Methods for producing such
golf balls are also disclosed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] The following is a brief description of the drawings, which
are presented for the purposes of illustrating the disclosure set
forth herein and not for the purposes of limiting the same.
[0030] FIG. 1 is a cross-sectional view of one exemplary embodiment
of the present disclosure.
DETAILED DESCRIPTION
[0031] Disclosed herein, in various embodiments, are multi-layered
RIM covered golf balls having improved structural configurations
and characteristics. The balls exhibit low spin when struck by a
driver off the tee and high initial velocity, resulting in
increased distance. Furthermore, the balls produce acceptable spin
around the green when struck with a high lofted club.
[0032] A more complete understanding of the compositions, products,
processes and apparatuses disclosed herein can be obtained by
reference to the accompanying drawing. This figure is merely a
schematic representation based on convenience and the present
development, and is, therefore, not intended to indicate relative
size and dimensions of the golf balls and/or components
thereof.
[0033] Although specific terms are used in the following
description for the sake of clarity, these terms are intended to
refer only to the particular structure of the embodiments selected
for illustration in the drawing, and are not intended to define or
limit the scope of the disclosure. In the drawing and the following
description below, it is to be understood that like numeric
designations refer to component of like function.
[0034] Referring to FIG. 1, a multi-layer golf ball 10 is
illustrated. In this embodiment, golf ball 10 comprises core 12,
mantle 14, and cover 16.
[0035] The above noted properties and/or characteristics, as well
as the principle features of the various components of the balls,
are more particularly described below.
Properties and Characteristics
[0036] Two principal properties involved in golf ball performance
are resilience and compression. Resilience is determined by the
coefficient of restitution (COR), i.e., the constant "e" which is
the ratio of the relative velocity of an elastic sphere after
direct impact to that before impact. As a result, the coefficient
of restitution ("e") can vary from 0 to 1, with 1 being equivalent
to a perfectly or completely elastic collision and 0 being
equivalent to a perfectly or completely inelastic collision.
[0037] Resilience, along with additional factors such as club head
speed, angle of trajectory, and ball construction and surface
configuration (i.e., dimple pattern), generally determines the
distance a ball will travel when hit. Since club head speed and the
angle of trajectory are factors not easily controllable by a
manufacturer, factors of concern among manufacturers are the COR,
the ball construction and the surface configuration of the
ball.
[0038] The COR in solid core balls is a function of the composition
of the molded core and of the cover. In balls containing a wound
core (i.e., balls comprising a liquid or solid center, elastic
windings, and a cover), the COR is a function of not only the
composition of the center and the cover, but also the composition
and tension of the elastomeric windings.
[0039] The COR is the ratio of the outgoing velocity to the
incoming velocity. In the examples of this application, the COR of
a golf ball was measured by propelling a ball horizontally at a
speed of 125.+-.1 feet per second (fps) against a generally
vertical, hard, flat steel plate and measuring the ball's incoming
and outgoing velocity electronically. Speeds were measured with a
pair of Ohler Mark 55 ballistic screens, which provide a timing
pulse when an object passes through them. The screens are separated
by 36 inches and are located 25.25 inches and 61.25 inches from the
rebound wall. The ball speed was measured by timing the pulses from
screen 1 to screen 2 on the way into the rebound wall (as the
average speed of the ball over 36 inches), and then the exit speed
was timed from screen 2 to screen 1 over the same distance. The
rebound wall was tilted 2 degrees from a vertical plane to allow
the ball to rebound slightly downward in order to miss the edge of
the cannon that fired it.
[0040] As indicated above, the incoming speed should be 125.+-.1
fps. Furthermore, the correlation between COR and forward or
incoming speed has been studied and a correction has been made over
the .+-.1 fps range so that the COR is reported as if the ball had
an incoming speed of exactly 125.0 fps.
[0041] Compression is another important property involved in the
performance of a golf ball. The compression of the ball can affect
the playability of the ball on striking and the sound or "click"
produced. Similarly, compression can affect the "feel" of the ball
(i.e., hard or soft responsive feel), particularly in chipping and
putting.
[0042] Moreover, while compression itself has little bearing on the
distance performance of a ball, compression can affect the
playability of the ball on striking. The degree of compression of a
ball against the club face and the softness of the cover influences
the resultant spin rate.
[0043] The term "compression" utilized in the golf ball trade
generally defines the overall deflection that a golf ball undergoes
when subjected to a compressive load. For example, compression
indicates the amount of change in golf ball's shape upon striking.
The development of solid core technology in two-piece or
multi-piece solid balls has allowed for much more precise control
of compression in comparison to thread wound three-piece balls.
This is because in the manufacture of solid core balls, the amount
of deflection or deformation is precisely controlled by the
chemical formula used in making the cores. This differs from wound
three-piece balls wherein compression is controlled in part by the
winding process of the elastic thread. Thus, two-piece and
multi-layer solid core balls exhibit much more consistent
compression readings than balls having wound cores such as the
thread wound three-piece balls.
[0044] In the past, PGA compression related to a scale of from 0 to
200 given to a golf ball. The lower PGA compression value, the
softer the feel of the ball upon striking. In practice, tournament
quality balls have compression ratings around 40 to 110, and
preferably around 50 to 100.
[0045] In determining PGA compression using the 0 to 200 scale, a
standard force is applied to the external surface of the ball. A
ball which exhibits no deflection (0.0 inches in deflection) is
rated 200 and a ball which deflects {fraction (2/10)}th of an inch
(0.2 inches) is rated 0. Every change of 0.001 of an inch in
deflection represents a 1 point drop in compression. Consequently,
a ball which deflects 0.1 inches (100.times.0.001 inches) has a PGA
compression value of 100 (i.e., 200 to 100) and a ball which
deflects 0.110 inches (110.times.0.001 inches) has a PGA
compression of 90 (i.e., 200 to 110).
[0046] In order to assist in the determination of compression,
several devices have been employed by the industry. For example,
PGA compression is determined by an apparatus fashioned in the form
of a small press with an upper and lower anvil. The upper anvil is
at rest against a 200-pound die spring, and the lower anvil is
movable through 0.300 inches by means of a crank mechanism. In its
open position, the gap between the anvils is 1.780 inches, allowing
a clearance of 0.200 inches for insertion of the ball. As the lower
anvil is raised by the crank, it compresses the ball against the
upper anvil, such compression occurring during the last 0.200
inches of stroke of the lower anvil, the ball then loading the
upper anvil which in turn loads the spring. The equilibrium point
of the upper anvil is measured by a dial micrometer if the anvil is
deflected by the ball more than 0.100 inches (less deflection is
simply regarded as zero compression) and the reading on the
micrometer dial is referred to as the compression of the ball. When
golf ball components (i.e., centers, cores, mantled core, etc.)
smaller than 1.680 inches in diameter are utilized, metallic shims
are included to produce the combined diameter of the shims and the
component to be 1.680 inches.
[0047] An example to determine PGA compression can be shown by
utilizing a golf ball compression tester produced by OK Automation,
Sinking Spring, Pa. (formerly, Atti Engineering Corporation of
Newark, N.J.). The compression tester produced by OK Automation is
calibrated against a calibration spring provided by the
manufacturer. The value obtained by this tester relates to an
arbitrary value expressed by a number which may range from 0 to
100, although a value of 200 can be measured as indicated by two
revolutions of the dial indicator on the apparatus. The value
obtained defines the deflection that a golf ball undergoes when
subjected to compressive loading. The Atti test apparatus consists
of a lower movable platform and an upper movable spring-loaded
anvil. The dial indicator is mounted such that is measures the
upward movement of the spring-loaded anvil. The golf ball to be
tested is placed in the lower platform, which is then raised a
fixed distance. The upper portion of the golf ball comes in contact
with and exerts a pressure on the spring-loaded anvil. Depending
upon the distance of the golf ball to be compressed, the upper
anvil is forced upward against the spring.
[0048] Furthermore, additional compression devices may also be
utilized to monitor golf ball compression such as a Whitney Tester,
Whitney Systems, Inc., Chelsford, Mass., or an Instron Device,
Instron Corporation, Canton, Mass. Herein, compression was measured
using an Instron.TM. Device (model 5544), Instron Corporation,
Canton, Mass. Compression of a golf ball, core, or golf ball
component is measured to be the deflection (in inches) caused by a
200 lb. load applied in a Load Control Mode at the rate of 15 kips,
and approach speed of 20 inches per minute, with a preload of 0.2
lbf plus the system compliance of the device.
[0049] As used herein, "Shore D hardness" of a cover is measured
generally in accordance with ASTM D-2240, except the measurements
are made on the curved surface of a molded cover, rather than on a
plaque. Furthermore, the Shore D hardness of the cover is measured
while the cover remains over the core. When a hardness measurement
is made on a dimpled cover, Shore D hardness is measured at a land
area of the dimpled cover.
[0050] "Shore B hardness" is similar to "Shore D hardness" set
forth above, except a different tension on the stylus is utilized.
This tension is lower to avoid puncturing the material which may
occur when softer materials are being measured.
[0051] A "Mooney unit" is an arbitrary unit used to measure the
plasticity of raw or unvulcanized rubber. The plasticity in Mooney
units is equal to the torque, measured on an arbitrary scale, on a
disk in a vessel that contains rubber at a temperature of
212.degree. F. (100.degree. C.) and that rotates at two revolutions
per minute. The measurement of Mooney viscosity, i.e. Mooney
viscosity [ML.sub.1+4(100.degree. C.], is defined according to the
standard ASTM D-1646, herein incorporated by reference. In ASTM
D-1646, it is stated that the Mooney viscosity is not a true
viscosity, but a measure of shearing torque over a range of
shearing stresses. Measurement of Mooney viscosity is also
described in the Vanderbilt Rubber Handbook, 13th Ed., (1990),
pages 565-566, also herein incorporated by reference. Generally,
polybutadiene rubbers have Mooney viscosities, measured at
212.degree. F., of from about 25 to about 65. Instruments for
measuring Mooney viscosities are commercially available such as a
Monsanto Mooney Viscometer, Model MV 2000. Another commercially
available device is a Mooney viscometer made by Shimadzu Seisakusho
Ltd.
[0052] As used herein, the term "phr" refers to the number of parts
by weight of a particular component in an elastomeric or rubber
mixture, relative to 100 parts by weight of the total elastomeric
or rubber mixture.
The Core
[0053] The core 12 of the golf ball of the present disclosure is a
relatively hard, high compression, molded core. In embodiments, it
is a molded core comprising a polybutadiene composition containing
at least one curing agent. Polybutadiene has been found to be
particularly useful because it imparts to the golf balls a
relatively high COR. Polybutadiene can be cured using a free
radical initiator such as a peroxide. A broad range for the Mw of
the polybutadiene composition is from about 50,000 to about
1,000,000; a narrower range is from about 50,000 to about 500,000.
A high cis-polybutadiene, such as a cis-1-4-polybutadiene, is
preferably employed, or a blend of high cis-1-4-polybutadiene with
other elastomers may also be utilized. In specific embodiments, a
high cis-1-4-polybutadiene having a M.sub.w of from about 100,000
to about 500,000 is employed.
[0054] A specific polybutadiene which may be used in the core of
certain embodiments of the present disclosure features a cis-1,4
content of at least 90% and preferably greater than 96% such as
Cariflex.RTM. BR-1220 currently available from Dow Chemical,
France; and Taktene.RTM. 220 currently available from Bayer,
Orange, Tex.
[0055] For example, Cariflex.RTM. BR-1220 polybutadiene and
Taktene.RTM. 220 polybutadiene may be utilized alone, in
combination with one another, or in combination with other
polybutadienes. Generally, these other polybutadienes have Mooney
viscosities in the range of about 25 to 65 or higher. The general
properties of BR-1220 and Taktene.RTM. 220 are set forth below.
[0056] A. Properties of Cariflex.RTM. BR-1220 Polybutadiene
1 Physical Properties: Polybutadiene Rubber CIS 1,4 Content -
97%-99% Min. Stabilizer Type - Non Staining Total Ash - 0.5% Max.
Specific Gravity - 0.90-0.92 Color - Transparent, clear, Lt. Amber
Moisture - 0.3% max. ASTM .RTM. 1416.76 Hot Mill Method Polymer
Mooney Viscosity - (35-45 Cariflex .RTM.) (ML.sub.1+4 @ 212.degree.
F.) 90% Cure - 10.0-13.0 Polydispersity 2.5-3.5 Molecular Weight
Data: Trial 1 Trial 2 M.sub.n 80,000 73,000 M.sub.w 220,000 220,000
M.sub.z 550,000 M.sub.peak 110,000
[0057] B. Properties of Taktene.RTM. 220 Polybutadiene
2 Physical Properties: Polybutadiene Rubber CIS 1,4 Content (%) -
98% Typical Stabilizer Type - Non Staining 1.0-1.3% Total Ash -
0.25 Max. Raw Polymer Mooney Visc. -35-45 40 Typical
(ML.sub.1+4'@212 Deg. F./212.degree. F.) Specific Gravity - 0.91
Color - Transparent - almost colorless (15 APHA Max.) Moisture % -
0.30% Max. ASTM .RTM. 1416-76 Hot Mill Method Product A relatively
low to mid Mooney viscosity, non-staining, Description solution
polymerized, high cis-1,4-polybutadiene rubber. Raw Polymer
Properties Property Range Test Method Mooney viscosity 40
.A-inverted. 5 ASTM .RTM. D 1646 ML.sub.1+4(212.degree. F.)
Volatile matter (wt %) 0.3 max. ASTM .RTM. D 1416 Total Ash (wt %)
0.25 max. ASTM .RTM. D 1416 Cure.sup.(1)(2) Minimum torque
Characteristics M.sub.L (dN .multidot. m) 9.7 .A-inverted. 2.2 ASTM
.RTM. D 2084 (lbf) .multidot. in) 8.6 .A-inverted. 1.9 ASTM .RTM. D
2084 Maximum torque M.sub.H (dN .multidot. m) 35.7 .A-inverted. 4.8
ASTM .RTM. D 2084 (lbf .multidot. in) 31.6 .A-inverted. 4.2 ASTM
.RTM. D 2084 t.sub.21 (min) 4 .A-inverted. 1.1 ASTM .RTM. D 2084
t'50 (min) 9.6 .A-inverted. 2.5 ASTM .RTM. D 2084 t'90 (min) 12.9
.A-inverted. 3.1 ASTM .RTM. D 2084 Other Product Features Property
Typical Value Specific gravity 0.91 Stabilizer type Non-staining
.sup.(1)Monsanto Rheometer at 160.degree. C., 1.7 Hz (100 cpm), 1
degree arc, micro-die .sup.(2)Cure characteristics determined on
ASTM .RTM. D 3189 MIM mixed compound: TAKTENE .RTM. 220 100 (parts
by mass) Zinc oxide 3 Stearic acid 2 IRB #6 black (N330) 60
Naphthenic oil 15 TBBS 0.9 Sulfur 1.5 * This specification refers
to product manufactured by Bayer Corp., Orange, Texas, U.S.A.
[0058] An example of a high Mooney viscosity polybutadiene suitable
for use with the present development includes Cariflex.RTM. BCP
820, from Shell Chimie of France. Although this polybutadiene
produces cores exhibiting higher COR values, it is somewhat
difficult to process using conventional equipment. The properties
and characteristics of this preferred polybutadiene are set forth
below.
Properties of Shell Chimie BCP 820 (Also Known As BR-1202J)
[0059]
3 Property Value Mooney Viscosity (approximate) 70-83 Volatiles
Content 0.5% maximum Ash Content 0.1% maximum Cis 1,4-polybutadiene
Content 95.0% minimum Stabilizer Content 0.2 to 0.3% Polydispersity
2.4-3.1 Molecular Weight Data: Trial 1 Trial 2 M.sub.n 110,000
111,000 M.sub.w 300,000 304,000 M.sub.z 680,000 M.sub.peak
175,000
[0060] Examples of further polybutadienes include those obtained by
using a neodymium-based catalyst, such as Neo Cis 40 and Neo Cis 60
from Enichem, Polimeri Europa America, 200 West Loop South, Suite
2010, Houston, Tex. 77027, and those obtained by using a neodymium
based catalyst, such as CB-22, CB-23, and CB-24 from Bayer Co.,
Pittsburgh, Pa. The properties of these polybutadienes are given
below.
[0061] A. Properties of Neo Cis 40 and 60
4 Properties of Raw Polymer Microstructure 1,4 cis (typical) 97.5%
1,4 trans (typical) 1.7% Vinyl (typical) 0.8% Volatile Matter (max)
0.75% Ash (max) 0.30% Stabilizer (typical) 0.50% Mooney Viscosity,
ML.sub.1+4 at 100.degree. C. 38-48 and 60-66 Properties of compound
(typical) Vulcanization at 145.degree. C. Tensile strength, 35'
cure, 16 MPa Elongation, 35' cure, 440% 300% modulus, 35' cure, 9.5
MPa
[0062] B. Properties of CB-22
5 TESTS RESULTS SPECIFICATIONS 1. Mooney-Viscosity ML1 + 4 100
Cel/ASTM .RTM.-sheet ML1 + 1 Minimum 58 MIN. 58 ME Maximum 63 MAX.
68 ME Median 60 58-68 ME 2. Content of ash DIN 53568 Ash 0.1 MAX.
0.5% 3. Volatile matter heating 3 h/105 Cel Loss in weight 0.11
MAX. 0.5% 4. Organic acid Bayer Nr.18 Acid 0.33 MAX.1.0% 5. CIS-1,4
content IR-spectroscopy CIS 1,4 97.62 MIN.96.0% 6. Vulcanization
behavior Monsanto MDR/160 Cel DIN 53529 Compound after ts01 3.2
2.5-4.1 min t50 8.3 6.4-9.6 min t90 13.2 9.2-14.0 min s'min 4.2
3.4-4.4 dN .multidot. m s'max 21.5 17.5-21.5 dN .multidot. m 7.
Informative data Vulcanization 150 Cel 30 min Tensile ca. 15.0
Elongation at break ca. 450 Stress at 300% elongation ca. 9.5
[0063] C. Properties of CB-23
6 TESTS RESULTS SPECIFICATIONS 1. Mooney-Viscosity ML1 + 4 100
Cel/ASTM .RTM.-sheet ML1 + 4 Minimum 50 MIN. 46 ME Maximum 54 MAX.
56 ME Median 51 46-56 ME 2. Content of ash DIN 53568 0.09 MAX. 0.5%
Ash 3. Volatile matter DIN 53526 Loss in weight 0.19 MAX. 0.5% 4.
Organic acid Bayer Nr.18 Acid 0.33 MAX. 1.0% 5. CIS-1,4 content
IR-spectroscopy CIS 1,4 97.09 MIN. 96.0% 6. Vulcanization behavior
Monsanto MDR/160 Cel DIN 53529 Compound after MIN. 96.0 ts01 3.4
2.4-4.0 min t50 8.7 5.8-9.0 min t90 13.5 8.7-13.5 min s'min 3.1
2.7-3.8 dN .multidot. m s'max 20.9 17.7-21.7 dN .multidot. m 7.
Vulcanization test with ring Informative data Tensile ca. 15.5
Elongation at break ca. 470 Stress at 300% elongation ca. 9.3
[0064] D. Properties of CB-24
7 TESTS RESULTS SPECIFICATIONS 1. Mooney-Viscosity ML1 + 4 100
Cel/ASTM .RTM.-sheet ML1 + 4 Minimum 44 MIN. 39 ME Maximum 46 MAX.
49 ME Median 45 39-49 ME 2. Content of ash DIN 53568 Ash 0.12 MAX.
0.5% 3. Volatile matter DIN 53526 Loss in weight 0.1 MAX. 0.5% 4.
Organic acid Bayer Nr.18 Acid 0.29 MAX. 1.0% 5. CIS-1,4 content
IR-spectroscopy CIS 1,4 96.73 MIN. 96.0% 6. Vulcanization behavior
Monsanto MDR/160 Cel DIN 53529 Compound after masticator ts01 3.4
2.6-4.2 min t50 8.0 6.2-9.4 min 190 12.5 9.6-14.4 min s'min 2.8
2.0-3.0 dN .multidot. m s'max 19.2 16.3-20.3 dN .multidot. m 7.
Informative data Vulcanization 150 Cel 30 min Tensile ca 15.0
Elongation at break ca. 470 Stress at 300% elongation ca. 9.1
[0065] Alternative polybutadienes include fairly high Mooney
viscosity polybutadienes including the commercially available
BUNA.RTM. CB series polybutadiene rubbers manufactured by the Bayer
Co., Pittsburgh, Pa. The BUNA.RTM. CB series polybutadiene rubbers
are generally of a relatively high purity and light color. The low
gel content of the BUNA.RTM. CB series polybutadiene rubbers
ensures almost complete solubility in styrene. The BUNA.RTM. CB
series polybutadiene rubbers have a relatively high cis-1,4
content. Preferably, each BUNA.RTM. CB series polybutadiene rubber
has a cis-1,4 content of at least 96%. Additionally, each BUNA.RTM.
CB series polybutadiene rubber exhibits a different solution
viscosity, preferably from about 42 mPa.s to about 170 mPa.s, while
maintaining a relatively constant solid Mooney viscosity value
range, preferably of from about 38 to about 52. The BUNA.RTM. CB
series polybutadiene rubbers preferably have a vinyl content of
less than about 12%, more preferably a vinyl content of about 2%.
In this regard, below is a listing of commercially available
BUNA.RTM. CB series polybutadiene rubbers and the solution
viscosity and Mooney viscosity of each BUNA.RTM. CB series
polybutadiene rubber.
8 Solution Viscosity and Mooney Viscosity of BUNA .RTM. CB Series
Polybutadiene Rubbers BUNA .RTM. CB BUNA .RTM. CB BUNA .RTM. CB
BUNA .RTM. CB BUNA .RTM. CB Property 1405 1406 1407 1409 1410
Solution 50 +/- 7 60 +/- 7 70 +/- 10 90 +/- 10 100 +/- 10 Viscosity
mPa.multidot.s Mooney 45 +/- 5 45 +/- 5 45 +/- 5 45 +/- 5 45 +/- 5
Viscosity mL 1 + 4 100.degree. C. BUNA .RTM. CB BUNA .RTM. CB BUNA
.RTM. CB BUNA .RTM. CB BUNA .RTM. CB Property 1412 1414 1415 1416
10 Solution 120 +/- 10 140 +/- 10 150 +/- 10 160 +/- 10 140 +/- 20
Viscosity mPa.multidot.s Mooney 45 +/- 5 45 +/- 5 45 +/- 5 45 +/- 5
47 +/- 5 Viscosity mL 1 + 4 100.degree. C.
Properties
[0066]
9 BUNA .RTM. BUNA .RTM. BUNA .RTM. BUNA .RTM. Property Test Method
Units CB 1406 CB 1407 CB 1409 CB 1410 Catalyst Cobalt Cobalt Cobalt
Cobalt Cis-1,4 IR % .gtoreq.96 .gtoreq.96 .gtoreq.96 .gtoreq.96
Content Spectroscopy; AN-SAA 0422 Volatile ISO 248/ % .ltoreq.0.5
.ltoreq.0.5 .ltoreq.0.5 .ltoreq.0.5 Matter ASTM D 1416 Ash Content
ISO 247/ % .ltoreq.0.1 .ltoreq.0.1 .ltoreq.0.1 .ltoreq.0.1 ASTM D
1416 Mooney ISO 289/DIN MU 45 .+-. 5 45 .+-. 5 45 .+-. 5 45 .+-. 5
Viscosity ML 53 523/ASTM (1 + 4) 100.degree. C. D 1646 Solution
ASTM D 445/ mPa .multidot. s 60 .+-. 7 70 .+-. 7 90 .+-. 10 100
.+-. 10 Viscosity, 5% DIN 51 562 in styrene Styrene 08-02.08.CB ppm
.ltoreq.100 .ltoreq.100 .ltoreq.100 .ltoreq.100 insoluble: dry gel
Color in ISO 6271/ APHA .ltoreq.10 .ltoreq.10 .ltoreq.10 .ltoreq.10
styrene ASTM D 1209 Solubility in in in in aliphatic aliphatic
aliphatic aliphatic hydrocarbons hydrocarbons hydrocarbons
hydrocarbons Total Amount AN-SAA 0583 % 0.2 0.2 0.2 0.2 of
Stabilizer BUNA .RTM. BUNA .RTM. BUNA .RTM. BUNA .RTM. Property
Test Method Units CB 1412 CB 1414 CB 1415 CB 1416 Catalyst Cobalt
Cobalt Cobalt Cobalt Cis-1,4 IR % .gtoreq.96 .gtoreq.96 .gtoreq.96
.gtoreq.96 Content Spectroscopy; AN-SAA 0422 Volatile ISO 248/ %
.ltoreq.0.5 .ltoreq.0.5 .ltoreq.0.5 .ltoreq.0.5 Matter ASTM D 1416
Ash Content ISO 247/ % .ltoreq.0.1 .ltoreq.0.1 .ltoreq.0.1
.ltoreq.0.1 ASTM D 1416 Mooney ISO 289/DIN MU 45 .+-. 5 45 .+-. 5
45 .+-. 5 45 .+-. 5 Viscosity ML 53 523/ASTM (1 + 4) 100.degree. C.
D 1646 Solution ASTM D 445/ mPa .multidot. s 120 .+-. 10 140 .+-.
10 150 .+-. 10 160 .+-. 10 Viscosity, 5% DIN 51 562 in styrene
Styrene 08-02.08.CB Ppm .ltoreq.100 .ltoreq.100 .ltoreq.100
.ltoreq.100 insoluble: dry gel Color in ISO 6271/ APHA .ltoreq.10
.ltoreq.10 .ltoreq.10 .ltoreq.10 styrene ASTM D 1209 Solubility in
in in in aliphatic aliphatic aliphatic aliphatic hydrocarbons
hydrocarbons hydrocarbons hydrocarbons Total Amount AN-SAA 0583 %
0.2 0.2 0.2 0.2 of Stabilizer
[0067] In addition to the polybutadiene rubbers noted above,
BUNA.RTM. CB 10 polybutadiene rubber is also very desirous to be
included in the composition of the present development. BUNA.RTM.
CB 10 polybutadiene rubber has a relatively high cis-1,4 content,
good resistance to reversion, abrasion and flex cracking, good low
temperature flexibility and high resilience. The BUNA.RTM. CB 10
polybutadiene rubber preferably has a vinyl content of less than
about 12%, more preferably about 2% or less. Listed below is a
brief description of the properties of the BUNA.RTM. CB 10
polybutadiene rubber.
Properties of BUNA.RTM. CB 10 Polybutadiene Rubber
[0068]
10 Value Unit Test method Raw Material Properties Volatile Matter
.ltoreq.0.5 wt-% ISO 248/ASTM D 5668 Mooney viscosity ML(1 + 4) @
100.degree. C. 47 .+-. 5 MU ISO 289/ASTM D 1646 Solution viscosity,
5.43 wt % in 140 .+-. 20 mPa .multidot. s ASTM D 445/ISO 3105 (5%
toluene in toluene) Cis-1,4 content .gtoreq.96 wt-% IR
Spectroscopy, AN-SAA 0422 Color, Yellowness Index .ltoreq.10 ASTM E
313-98 Cobalt content .ltoreq.5 ppm DIN 38 406 E22 Total Stabilizer
content .gtoreq.0.15 wt-% AN-SAA 0583 Specific Gravity 0.91
Monsanto Rheometer MDR 2000E, 160"C/30 min./.alpha. = .+-.0.5"C
Vulcanization Properties (Test formulation from ISO 2476/ ASTM D
3189 (based on IRB 7)) Torque Minimum (ML) 3.5 .+-. 0.7 dNm ISO
6502/ASTM D5289 Torque Maximum (MH) 19.9 .+-. 2.4 dNm ISO 6502/ASTM
D5289 Scorch Time, t.s..sub.1 2.9 .+-. 0.6 min ISO 6502/ASTM D5289
Cure Time, t.c..sub.50 8.7 .+-. 1.7 min ISO 6502/ASTM D5289 Cure
Time, t.c..sub.90 12.8 .+-. 2.4 min ISO 6502/ASTM D5289
[0069] The polybutadiene utilized in the present development can
also be mixed with other elastomers. These include natural rubbers,
polyisoprene rubber, SBR rubber (styrene-butadiene rubber) and
others to produce certain desired core properties.
[0070] The elastomeric rubber composition also includes a curing
agent. The curing agent is the reaction product of a carboxylic
acid or acids and an oxide or carbonate of a metal such as zinc,
magnesium, barium, calcium, lithium, sodium, potassium, cadmium,
lead, tin, and the like. Exemplary unsaturated carboxylic acids are
acrylic acid, methacrylic acid, itaconic acid, crotonic acid,
sorbic acid, and the like, and mixtures thereof. Usually, the
selected acid is either acrylic or methacrylic acid. From about 15
to about 50, and specifically from about 17 to about 35 parts by
weight of the carboxylic acid salt, such as zinc diacrylate (ZDA),
is included per 100 parts of the elastomer components in the core
when a curing agent is included. The unsaturated carboxylic acids
and metal salts thereof are generally soluble in the elastomeric
base, or are readily dispersible. Examples of such commercially
available curing agents include the zinc acrylates and zinc
diacrylates available from Sartomer Company, Inc., 502 Thomas Jones
Way, Exton, Pa.
[0071] A free radical initiator is optionally included in the
elastomeric rubber composition; it is any known polymerization
initiator (a co-crosslinking agent) which decomposes during the
cure cycle. The term "free radical initiator" as used herein refers
to a chemical which, when added to the elastomeric blend, promotes
crosslinking of the elastomers. The amount of the selected
initiator present is dictated only by the requirements of catalytic
activity as a polymerization initiator. Suitable initiators include
peroxides, persulfates, azo compounds and hydrazides. Peroxides
which are readily commercially available are conveniently used in
the present development, generally in amounts of from about 0.1 to
about 10.0 and preferably in amounts of from about 0.3 to about 3.0
parts by weight per each 100 parts of elastomer, wherein the
peroxide has a 40% level of active peroxide.
[0072] Exemplary of suitable peroxides are dicumyl peroxide,
n-butyl 4,4'-bis (butylperoxy) valerate,
1,1-bis(t-butylperoxy)-3,3,5-trimethyl cyclohexane, di-t-butyl
peroxide and 2,5-di-(t-butylperoxy)-2,5 dimethyl hexane and the
like, as well as mixtures thereof. It will be understood that the
total amount of initiators used will vary depending on the specific
end product desired and the particular initiators employed.
[0073] Examples of such commercial available peroxides are
Luperco.TM. 230 or 231 XL, a peroxyketal manufactured and sold by
Atochem, Lucidol Division, Buffalo, N.Y., and Trigonox.TM. 17/40 or
29/40, a peroxyketal manufactured and sold by Akzo Chemie America,
Chicago, Ill. The one hour half life of Luperco.TM. 231 XL and
Trigonox.TM. 29/40 is about 112.degree. C., and the one hour half
life of Luperco.TM. 230 XL and Trigonox.TM. 17/40 is about
129.degree. C. Luperco.TM. 230 XL and Trigonox.TM. 17/40 are
n-butyl-4,4-bis(t-butylperoxy) valerate and Luperco.TM. 231 XL and
Trigonox.TM. 29/40 are 1,1-di(t-butylperoxy) 3,3,5-trimethyl
cyclohexane. Trigonox.TM. 42-40B is tert-Butyl
peroxy-3,5,5-trimethylhexanoate and is available from Akzo Nobel;
the liquid form of this agent is available from Akzo under the
designation Trigonox.TM. 42S.
[0074] Preferred co-agents which can be used with the above
peroxide polymerization agents include zinc diacrylate (ZDA), zinc
dimethacrylate (ZDMA), trimethylol propane triacrylate, and
trimethylol propane trimethacrylate, most preferably zinc
diacrylate. Other co-agents may also be employed and are known in
the art.
[0075] In further embodiments, the molded core includes a
difunctional acrylate. It serves the dual function of being a
curing agent and a co-agent to the free radical initiator. In
specific embodiments, the molded core includes zinc diacrylate.
[0076] The elastomeric polybutadiene compositions of the present
development can also optionally include one or more halogenated
organic sulfur compounds which serve as a peptizer. The peptizer is
usually a halogenated thiophenol of the formula below: 1
[0077] wherein R.sub.1-R.sub.5 are independently halogen, hydrogen,
alkyl, thiol, or carboxylated groups. At least one halogen group is
included, preferably 3-5 of the same halogenated groups are
included, and most preferably 5 of the same halogenated groups are
part of the compound. Examples of such fluoro-, chloro-, bromo-,
and iodo-thiophenols include, but are not limited to
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-tetrafluorothioph- enol;
2,3,5,6-tetrafluorothiophenol; 4-chlorotetrafluorothiophenol;
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; pentabromothiophenol;
2-bromothiophenol; 3-bromothiophenol; 4-bromothiophehol;
2,3-bromothiophenol; 2,4-bromothiophenol; 3,4-bromothiophenol;
3,5-bromothiophenol; 2,3,4-bromothiophenol; 3,4,5-bromothiophenol;
2,3,4,5-tetrabromothiopheno- l; 2,3,5,6-tetrabromothiophenol;
pentaiodothiophenol; 2-iodothiophenol; 3-iodothiophenol;
4-iodothiophenol; 2,3-iodothiophenol; 2,4-iodothiophenol;
3,4-iodothiophenol; 3,5-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; and their metal salts thereof, and
mixtures thereof. The metal salt may be salts of zinc, calcium,
potassium, magnesium, sodium, and lithium. Another material is
dodecanethiol.
[0078] In a specific embodiment, pentachlorothiophenol or zinc
pentachlorothiophenol is included in the elastomeric composition.
For example, RD 1302 of Rheim Chemie of Trenton, N.J. can be
included therein. RD 1302 is a 75% masterbatch of Zn PCTP in a
high-cis polybutadiene rubber.
[0079] Other suitable pentachlorothiphenols include those available
from Dannier Chemical, Inc., Tustin, Calif., under the designation
Dansof P.TM.. The product specifications of Dansof P.TM. are set
forth below:
11 Compound Name Pentachlorothiophenol Synonym (PCTP) CAS # n/a
Molecular Formula: C6CI5SH Molecular Weight: 282.4 Grade: Dansof P
Purity: 97.0% (by HLPC) Physical State: Free Flowing Powder
Appearance Light Yellow to Gray Moisture Content (K.F.) <0.4%
Loss on Drying (% by Wt.): <0.4% Particle Size: 80 mesh
[0080] A representative metallic salt of pentachlorothiophenol is
the zinc salt of pentachlorothiophenol (ZnPCTP) sold by Dannier
Chemical, Inc. under the designation Dansof Z.TM.. The properties
of this material are as follows:
12 Compound Name Zinc Salt of Pentachlorothiophenol Synonym
Zn(PCTP) CAS # n/a Molecular Formula: Molecular Weight: Grade: DR
14 Purity: =99.0% Physical State: Free Flowing Powder Appearance
Off-white/Gray Odor: Odorless Moisture Content (K.F.) <0.5% Loss
on Drying (% by Wt.): <0.5% Mesh Size: 100 Specific Gravity
2.33
[0081] The pentachlorothiophenol or metallic salt thereof is added
in an amount of 0.01 to 5.0 parts by weight, preferably 0.1 to 2.0
parts by weight, more preferably 0.5 to 1.0 parts by weight, on the
basis of 100 parts by weight of the elastomer.
[0082] In addition to the foregoing, filler materials can be
employed in the compositions of the development to control the
weight and density of the ball. Fillers which are incorporated into
the compositions should be in finely divided form, typically in a
size generally less than about 20 mesh, preferably less than about
100 mesh U.S. standard size. Preferably, the filler is one with a
specific gravity of from about 0.5 to about 19.0. Examples of
fillers which may be employed include, for example, silica, clay,
talc, mica, asbestos, glass, glass fibers, barytes (barium
sulfate), limestone, lithophone (zinc sulphide-barium sulfate),
zinc oxide, titanium dioxide, zinc sulphide, calcium metasilicate,
silicon carbide, diatomaceous earth, particulate carbonaceous
materials, micro balloons, aramid fibers, particulate synthetic
plastics such as high molecular weight polyethylene, polystyrene,
polyethylene, polypropylene, ionomer resins and the like, as well
as cotton flock, cellulose flock and leather fiber. Powdered metals
such as titanium, tungsten, aluminum, bismuth, nickel, molybdenum,
copper, brass and their alloys also may be used as fillers.
[0083] The amount of filler employed is primarily a function of
weight restrictions on the weight of a golf ball made from those
compositions. In this regard, the amount and type of filler will be
determined by the characteristics of the golf ball desired and the
amount and weight of the other ingredients in the core composition.
The overall objective is to closely approach the maximum golf ball
weight of 1.620 ounces (45.92 grams) set forth by the U.S.G.A.
[0084] The compositions of the development also may include various
processing aids known in the rubber and molding arts, such as fatty
acids. Generally, free fatty acids having from about 10 carbon
atoms to about 40 carbon atoms, preferably having from about 15
carbon atoms to about 20 carbon atoms, may be used. Fatty acids
which may be used include stearic acid and linoleic acids, as well
as mixtures thereof. When included in the compositions of the
development, the fatty acid component is present in amounts of from
about 1 part by weight per 100 parts elastomer, preferably in
amounts of from about 2 parts by weight per 100 parts elastomer to
about 5 parts by weight per 100 parts elastomer. Examples of
processing aids which may be employed include, for example, calcium
stearate, barium stearate, zinc stearate, lead stearate, basic lead
stearate, dibasic lead phosphite, dibutyltin dilaurate, dibutyltin
dimealeate, dibutyltin mercaptide, as well as dioctyltin and
stannane diol derivatives.
[0085] Furthermore, other additives known to those skilled in the
art can also be included in the core components of the embodiments
disclosed herein. These additions are included in amounts
sufficient to produce the desired characteristics.
[0086] The core may be made by conventional mixing and compounding
procedures used in the rubber industry. Different types and various
amounts of materials are utilized to produce a molded core
composition having the compression, resiliency, etc., properties
desired.
[0087] For example, the ingredients may be intimately mixed using,
for example, two roll mills or a BANBURY.RTM. mixer, until the
composition is uniform, usually over a period of from about 5 to 20
minutes. The sequence of addition of components is not critical.
One blending sequence is as follows.
[0088] The elastomer, such as the polybutadienes, Cariflex.RTM.
1220, Neo-Cis.RTM. 60, Taktene.RTM., or blends thereof, zinc
pentachlorothiophenol (optional), and other components comprising
the elastomeric rubber composition are blended for about 7 minutes
in an internal mixer such as a BANBURY.RTM. mixer. As a result of
shear during mixing, the temperature rises to about 200.degree. F.
The initiator and diisocyanate (optional) are then added and the
mixing continued until the temperature reaches about 220.degree. F.
whereupon the batch is discharged onto a two roll mill, mixed for
about one minute and sheeted out. The mixing is desirably conducted
in such a manner that the composition does not reach incipient
polymerization temperature during the blending of the various
components.
[0089] The composition can be formed into a core by any one of a
variety of molding techniques, e.g. compression, transfer molding,
etc. If the core is compression molded, the sheet is then rolled
into a "pig" and then placed in a BARWELL.RTM. preformer and slugs
are produced. The slugs are then subjected to compression molding
at about 320.degree. F. for about 14 minutes. After molding, the
molded cores are cooled at room temperature for about 4 hours or in
cold water for about one hour.
[0090] Usually the curable component of the composition will be
cured by heating the composition at elevated temperatures on the
order of from about 275.degree. F. to about 350.degree. F.,
preferably and usually from about 290.degree. F. to about
325.degree. F., with molding of the composition effected
simultaneously with the curing thereof. When the composition is
cured by heating, the time required for heating will normally be
short, generally from about 10 to about 20 minutes, depending upon
the particular curing agent used. Those of ordinary skill in the
art relating to free radical curing agents for polymers are
conversant with adjustments to cure times and temperatures required
to effect optimum results with any specific free radical agent.
[0091] After molding, the core is removed from the mold and the
surface may be treated to facilitate adhesion thereof to the
covering materials. Surface treatment can be effected by any of the
several techniques known in the art, such as corona discharge,
ozone treatment, sand blasting, centerless grinding, and the like.
Alternatively, the cores are used in the as-molded state with no
surface treatment.
[0092] Further embodiments of the present invention may also
include thermoplastic cores. These cores may comprise a highly
neutralized ionomer (greater than 80%) and may comprise a fatty
acid or fatty acid metal salt, such as disclosed in co-pending U.S.
patent application Ser. No. 10/905,925, filed on Jan. 26, 2005, for
a Golf Ball With Thermoplastic Material, which is hereby
incorporated by reference in its entirety.
[0093] The resulting molded core generally has a diameter of about
1.0 to about 2.0 inches, preferably about 1.40 to about 1.60 inches
and more preferably from about 1.520 to about 1.550 inches.
Additionally, the weight of the core is adjusted so that the
finished golf ball closely approaches the U.S.G.A. upper weight
limit of 1.620 ounces. It has the high resiliency and hardness
(i.e., high compression) desired. The molded core exhibits a COR of
greater than 0.750, and preferably from about 0.780 to about 0.810,
and more preferably from about 0.785 to about 0.805, and a
compression (Instron) of greater than 0.0700, including from about
0.0750 to about 0.1300.
The Mantle
[0094] The mantle 14 of the golf ball of the present disclosure
preferably comprises an ionomeric resin, more preferably a blend of
high acid ionomer resins. Ionomeric resins are polymers containing
interchain ionic bonding. They are generally ionic copolymers of an
olefin, such as ethylene, and a metal salt of an unsaturated
carboxylic acid, such as acrylic acid, methacrylic acid, or maleic
acid. Metal ions, such as sodium, zinc, magnesium, etc., are used
to neutralize some portion of the acidic group in the copolymer
resulting in a thermoplastic elastomer exhibiting enhanced
properties, such as increased durability and hardness. There are
many commercial grades of ionomers available both from DuPont.RTM.
and Exxon.RTM., with a wide range of properties which vary
according to the type and amount of metal cations, molecular
weight, composition of the base resin (such as relative content of
ethylene and methacrylic and/or acrylic acid groups) and additive
ingredients such as reinforcement agents, and the like.
[0095] A suitable ionomer is a copolymer of an alpha-olefin and an
alpha, beta-unsaturated carboxylic acid. The acid copolymer may
contain anywhere from 1 to 30 percent by weight acid. A high acid
copolymer containing greater than 16% by weight acid, preferably
from about 17 to about 25 weight percent acid, and more preferably
about 20 weight percent acid, or a low acid copolymer containing
16% by weight or less acid may be used as desired. The acid
copolymer is neutralized with a metal cation salt capable of
ionizing or neutralizing the copolymer to the extent desired,
generally from about 10% to 100%. The amount of metal cation salt
needed is that which has enough metal to neutralize up to 100% of
the acid groups as desired.
[0096] Generally, the alpha-olefin has from 2 to 10 carbon atoms
and is preferably ethylene, and the unsaturated carboxylic acid is
a carboxylic acid having from about 3 to 8 carbons. Examples of
such acids include, but are not limited to, acrylic acid,
methacrylic acid, ethacrylic acid, chloroacrylic acid, crotonic
acid, maleic acid, fumaric acid, and itaconic acid. The carboxylic
acid of the acid copolymer is, in embodiments, acrylic acid or
methacrylic acid.
[0097] The ionomer mantle layer comprises any suitable ionomer
resin having the characteristics desired. Examples of such suitable
ionomer resins are commercially available from DuPont.RTM. under
the designation Surlyn.RTM. or from Exxon.RTM. under the
designation lotek.RTM.. The ionomers preferably have a high flex
modulus of from about 40 kpsi to about 100 kpsi, or from about 50
kpsi to about 85 kpsi, and in specific embodiments from about 60
kpsi to about 75 kpsi. The flex modulus is measured in accordance
to ASTM 6272-98, with the test specimen conditioned for 14
days.
[0098] Further embodiments of the present invention may include
intermediate layers comprising one or more ionomers which are
neutralized to greater than 80%. The intermediate layer may also
comprise ionomers comprising a fatty acid or fatty acid metal
salt.
[0099] The various compositions of the mantle may be produced
according to conventional melt blending procedures. In one
embodiment, a simple dry blend of the pelletized or granulated
copolymers which have previously been neutralized to a desired
extent (and colored masterbatch, if desired) may be prepared and
fed directly into the injection molding machine where
homogenization occurs in the mixing section of the barrel prior to
injection into the mold. If necessary, further additives, such as
an inorganic filler, may be added and uniformly mixed before
initiation of the molding process.
[0100] The resulting mantle has a Shore D hardness of from about 50
to about 80, including from about 60 to about 72, and in specific
embodiments from about 67 to about 72. It has a resilience of from
about 0.750 to about 0.830, including from about 0.805 to about
0.815, and about 0.810.
The Polyurethane/Polyurea Rim Cover
[0101] The outer layer, or cover layer 16, of the golf ball is a
polyurethane/polyurea RIM cover. As used here, the term
"polyurethane/polyurea" means a polyurethane, a polyurea,
combinations thereof, and blends thereof.
[0102] The exemplary embodiments also include methods of producing
golf balls, such as by RIM, which contain a
fast-chemical-reaction-produced component at the overall properties
desired. Particularly preferred forms of the exemplary embodiments
also provide for a golf ball with a thin, relatively hard,
fast-chemical-reaction-produced cover having good scuff and cut
resistance.
[0103] More specifically, the preferred method of forming a
fast-chemical-reaction-produced component for a golf ball according
to the disclosure is by a RIM process. In a RIM process, highly
reactive liquids are injected into a closed mold, mixed usually by
impingement and/or mechanical mixing and secondarily mixed in an
in-line device such as a peanut mixer, where they polymerize
primarily in the mold to form a coherent, molded article. The RIM
processes usually involve a rapid reaction between one or more
reactive components such as polyether--or polyester--polyol,
polyamine, or other material with an active hydrogen, and one or
more isocyanate--containing constituents, often in the presence of
a catalyst. The constituents are stored in separate tanks prior to
molding and may be first mixed in a mix head upstream of a mold and
then injected into the mold. The liquid streams are metered in the
desired weight to weight ratio, such that the ratio of the --NCO
groups to the active hydrogen groups is within a desired ration,
and fed into an impingement mix head, with mixing occurring under
high pressure, e.g., 1500 to 3000 psi. The liquid streams impinge
upon each other in the mixing chamber of the mix head and the
mixture is injected into the mold. One of the liquid streams
typically contains a catalyst for the reaction. The constituents
react rapidly after mixing to gel and form polyurethane/polyurea
polymers. Epoxies and various unsaturated polyesters also can be
molded by RIM.
[0104] RIM differs from non-reaction injection molding processes in
a number of ways. The main distinction is that in RIM a chemical
reaction takes place in the mold to transform a monomer or adducts
to polymers and the components are in liquid form. Thus, a RIM mold
need not be made to withstand the pressures which occur in a
conventional injection molding. In contrast, injection molding is
conducted at high molding pressures in the mold cavity by melting a
solid resin and conveying it into a mold, with the molten resin
often being at about 150 to about 350.degree. C. At this elevated
temperature, the viscosity of the molten resin usually is in the
range of 50,000 to about 1,000,000 centipoise, and is typically
around 200,000 centipoise. In an injection molding process, the
solidification of the resins occurs after about 10 to 90 seconds,
depending upon the size of the molded product, the temperature and
heat transfer conditions, and the hardness of the injection molded
material. Subsequently, the molded product is removed from the
mold. There is no significant chemical reaction taking place in an
injection molding process when the thermoplastic resin is
introduced into the mold. In contrast, in a RIM process, the
chemical reaction typically takes place in less than about 2
minutes, preferably in under one minute, and in many cases in about
30 seconds or less.
[0105] The fast-chemical-reaction-produced component can
incorporate suitable additives and/or fillers. When the component
is an outer cover layer, pigments or dyes, accelerators and UV
stabilizers can be added. Examples of suitable optical brighteners
which probably can be used include Uvitex.TM. and Eastobrite.TM.
OB-1. An example of a suitable white pigment is titanium dioxide.
Examples of suitable and UV light stabilizers are provided in
commonly assigned U.S. Pat. No. 5,494,291. Fillers which can be
incorporated into the fast-chemical-reaction-produce- d cover or
core component include those listed below in the definitions
section. Furthermore, compatible polymeric materials, such as
polyurethane ionomers, polyamides, etc., can be added.
[0106] Catalysts can be added to the RIM polyurethane/polyurea
system starting materials as long as the catalysts generally do not
react with the constituent with which they are combined. Suitable
catalysts include those which are known to be useful with
polyurethanes and polyureas. These catalysts include dibutyl tin
dilaurate or triethylenediamine.
[0107] The reaction mixture viscosity should be sufficiently low to
ensure that the mold is completely filled. The reactant materials
generally are preheated to about 80.degree. F. to about 200.degree.
F. and preferably to 100.degree. F. to about 180.degree. F. before
they are mixed. In most cases it is necessary to preheat the mold
to, e.g., from about 80.degree. F. to about 200.degree. F., to
provide for proper injection viscosity and system reactivity.
[0108] Molding at lower temperatures is beneficial when, for
example, the cover is molded over a core. Normally, at higher
temperature molding processes, the core may expand during molding.
Such core expansion is not of such a concern when molding at lower
temperatures utilizing RIM.
[0109] Polyurethanes/polyureas are polymers which are used to form
a broad range of products. Polyurethane and/or polyurea polymers
are typically made from three reactants: alcohols, amines, and
isocyanate-containing compounds. They react with the
isocyanate-containing compound, which is generally referred to as
an "isocyanate." The constituent containing the alcohols, amines or
other reactive hydrogen groups is sometimes referred to
collectively as the polyol constituent of the RIM formulation. The
constituent containing the isocyanate or isocyanate prepolymer is
usually referred to as the isocyanate constituent of the RIM
formulation.
[0110] Several chemical reactions may occur during polymerization
of isocyanate and polyol. Isocyanate groups (--N.dbd.C.dbd.O) that
react with alcohols form a polyurethane, whereas isocyanate groups
that react with an amine group form a polyurea. A polyurethane
itself may react with an isocyanate to form an allophanate and a
polyurea can react with an isocyanate to form a biuret. Because the
biuret and allophanate reactions occur on an already-substituted
nitrogen atom of the polyurethane or polyurea, these reactions
increase cross-linking within the polymer.
[0111] The polyol component typically contains additives, such as
stabilizers, flow modifiers, catalysts, combustion modifiers,
blowing agents, fillers, pigments, optical brighteners, surfactants
and release agents to modify physical characteristics of the cover.
Polyurethane/polyurea constituent molecules that were derived from
recycled polyurethane can be added in the polyol component.
[0112] Cross linking occurs between the isocyanate groups (--NCO)
and the polyol's hydroxyl end-groups (--OH) and/or the active
hydrogens (--H) of the amines or polyamines. Additionally, the
end-use characteristics of polyurethanes can also be controlled by
different types of reactive chemicals and processing parameters.
For example, catalysts are utilized to control polymerization
rates. Depending upon the processing method, reaction rates can be
very quick (as in the case for some reaction injection molding
systems (i.e., RIM).
[0113] A wide range of combinations of polyisocyanates and polyols,
as well as other ingredients, are available. Furthermore, the
end-use properties of polyurethanes can be controlled by the type
of polyurethane utilized, i.e., whether the material is thermoset
(cross linked molecular structure) or thermoplastic (linear
molecular structure). In the present RIM process, thermosetting
polyurethanes/polyureas are utilized.
[0114] In this regard, polyurethanes are typically classified as
thermosetting or thermoplastic. A polyurethane becomes irreversibly
"set" when a polyurethane prepolymer is cross linked with a
polyfunctional curing agent, such as a polyamine or a polyol. The
prepolymer typically is made from polyether or polyester.
Diisocyanate polyethers are sometimes preferred because of their
water resistance.
[0115] The physical properties of thermoset polyurethanes are
controlled substantially by the degree of cross linking. Tightly
cross linked polyurethanes/polyureas are fairly rigid and strong. A
lower amount of cross linking results in materials that are
flexible and resilient. Thermoplastic polyurethanes have some cross
linking, but primarily by physical means. The crosslinkings bonds
can be reversibly broken by increasing temperature, as occurs
during molding or extrusion.
[0116] Polyurethane materials suitable for the exemplary
embodiments are formed by the reaction of a polyisocyanate, a
polyol, and optionally one or more chain extenders. The polyol
component includes any suitable polyether- or polyesterpolyol.
Additionally, in an alternative embodiment, the polyol component
may contain polybutadiene diol as a chain extender. The chain
extenders include, but are not limited, to diols, triols and amine
extenders. Any suitable polyisocyanate may be used to form a
polyurethane according to the exemplary embodiment. The
polyisocyanate is preferably selected from the group of
diisocyanates including, but not limited, to 4,4N-diphenylmethane
diisocyanate ("MDI"); 2,4-toluene diisocyanate ("TDI"); m-xylylene
diisocyanate ("XDI"); methylene bis-(4-cyclohexyl isocyanate)
("HMDI"); hexamthylene diisocyanate (HDI);
naphthalene-1,5,-diisocyanate ("NDI"); 3,3N-dimethyl-4,4N-biphenyl
diisocyanate ("TODI"); 1,4-diisocyanate benzene ("PPDI");
phenylene-1,4-diisocyanate; and 2,2,4- or 2,4,4-trimethyl
hexamethylene diisocyanate ("TMDI").
[0117] Other less preferred diisocyanates include, but are not
limited to, isophorone diisocyanate ("IPDI"); 1,4-cyclohexyl
diisocyanate ("CHDI"); diphenylether-4,4N-diisocyanate;
p,pN-diphenyl diisocyanate; lysine diisocyanate ("LDI"); 1,3-bis
(isocyanato methyl) cyclohexane; and polymethylene polyphenyl
isocyanate ("PMDI").
[0118] One polyurethane component which can be used in the
exemplary embodiment incorporates TMXDI (META) aliphatic isocyanate
(Cytec Industries, West Paterson, N.J.). Polyurethanes based on
meta-tetramethylxylyliene diisocyanate can provide improved gloss
retention, UV light stability, thermal stability and hydrolytic
stability. Additionally, TMXDI (META) aliphatic isocyanate has
demonstrated favorable toxicological properties. Furthermore,
because it has a low viscosity, it is usable with a wider range of
diols (to polyurethane) and diamines (to polyureas). If TMXDI is
used, it typically, but not necessarily, is added as a direct
replacement for some or all of the other aliphatic isocyanates in
accordance with the suggestions of the supplier. Because of slow
reactivity of TMXDI, it may be useful or necessary to use catalysts
to have practical demolding times. Hardness, tensile strength and
elongation can be adjusted by adding further materials in
accordance with the supplier's instructions.
[0119] Suitable glycol chain extenders include, but are not limited
to ethylene glycol; propane glycol; butane glycol; pentane glycol;
hexane glycol; benzene glycol; xylenene glycol; 1,4-butane diol;
1,3-butane diol; 2,3-dimethyl-2,3-butane diol; and dipropylene
glycol.
[0120] Suitable amine extenders include, but are not limited to,
tetramethyl-ethylenediamine; dimethylbenzylamine;
diethylbenzylamine; pentamethyldiethylenetriamine; dimethyl
cyclohexylamine; tetramethyl-1,3-butanediamine;
1,2-dimethylimidazole; 2-methylimidazole;
pentamethyidipropylenetriamine; diethyl toluene diamine (DETDA) and
bis-(dismethylaminoethylether).
[0121] The polyurethane/polyurea which is selected for use as the
golf ball cover preferably has a Shore D hardness of 20 to 80, more
preferably 50 to 70, and most preferably 60 to 68. Alternatively,
Shore B can be utilized to characterize the cover hardness.
Comparably, Shore B values are from about 50 to about 100,
including from about 70 to about 100 and from about 80 to about
100. The polyurethane which is to be used for a cover layer
preferably has a flex modulus of 1 to 310 kpsi, more preferably 5
to 100 kpsi, and most preferably 5 to 20 kpsi for a soft cover
layer and 30 to 100 kpsi for a hard cover layer.
[0122] Non-limiting examples of polyurethanes/polyureas suitable
for use in the layers include Bayer Bayflex.RTM. 110-50; Bayer
Bayflex.RTM. MP-10,000; Crompton.RTM. Vibra RIM 813A and Vibra RIM
813B; and Dow.RTM. Spectrim RD, amongst others. The general
characteristics of these materials are briefly described below.
[0123] BAYFLEX MP-10,000 is a two component system, consisting of
Component A and Component B. Component A comprises the diisocyanate
and Component B comprises the polyether polyol plus additional
curatives, extenders, etc. The following information is provided by
the BAYFLEX MP-10,000 MSDS sheet, regarding the constituent
components.
[0124] Component A
13 1. Chemical Product Information (Section 1) Product Name:
BAYFLEX MP-10,000 Component A Chemical Family: Aromatic Isocyanate
Prepolymer Chemical Name: Diphenylmethane Diisocyanate (MDI)
Prepolymer Synonyms: Modified Diphenylmethane Diisocyanate 2.
Composition/Information on Ingredients (Section 2) Ingredient
Concentration 4,4'-Diphenylmethane Diisocyanate (MDI) 53-54%
Diphenylmethane Diisocyanate (MDI) (2,2; 2,4) 1-10% 3. Physical and
Chemical Properties (Section 9) Molecular Weight: Average 600-700
4. Regulatory Information (Section 15) Component Concentration
4,4'-Diphenylmethane Diisocyanate (MDI) 53-54% Diphenylmethane
Diisocyanate (MDI) (2,2; 2,4) 1-10% Polyurethane Prepolymer
40-50%
[0125] Component B
14 1. Chemical Product Information (Section 1) Product Name:
BAYFLEX MP-10,000 Component B Chemical Family: Polyether Polyol
System Chemical Name: Polyether Polyol containing
Diethyltoluenediamine 2. Composition/Information on Ingredients
(Section 2) Ingredient Concentration Diethyltoluenediamine 5-15% 3.
Transportation Information (Section 14) Technical Shipping Name:
Polyether Polyol System Freight Class Bulk: Polypropylene Glycol
Freight Class Package: Polypropylene Glycol 4. Regulatory
Information (Section 15) Component Name Concentration
Diethyltoluenediamine 5-15% Pigment dispersion Less than 5%
Polyether Polyol 80-90%
[0126] Additionally, Bayer reports the following further
information:
[0127] Component A
15 Isocyanate: 4,4 diphenylmethane diisocyanate (MDI)
Functionality: 2.0 Curing Agents: None Diisocyanate 60% free MDI;
remaining 40% has reacted Concentration: % NCO: 22.6 (overall)
Equivalent Weight: 186
[0128] Component B
16 Polyol: Trio containing derivatives of polypropylene glycol
Functionality: 3.0 Equivalent Weight: 2,000 Amine Extender:
Diethyltoluenediamine (equivalent weight of 88)
[0129] According to Bayer, the following general properties are
produced by this RIM system:
17 ASTM Test Property Typical Physical Properties Value Method
General Specific Gravity 1.1 D 792 Density 68.7 lb/ft.sup.3 D 1622
Thickness 0.118 in Shore Hardness 90 A, 110 D D 2240 Mold Shrinkage
1.42% (Bayer) Water Immersion, 0.014 in/in (Bayer) Length Increase
Water Absorption: 24 Hours 3.3% (Bayer) Water Absorption: 240 Hours
5.0% (Bayer) Mechanical Tensile Strength, Ultimate 2,200
lb/in.sup.2 D 638/D 412 Elongation at Break 300% D 638/D 412
Flexural Modulus: 149.degree. F. 7,900 lb/in.sup.2 D 790 Flexural
Modulus: 73.degree. F. 10,000 lb/in.sup.2 D 790 Flexural Modulus:
-22.degree. F. 23,600 lb/in.sup.2 D 790 Tear Strength, Die C 240
lbf/in D 624 Thermal Coefficient of Linear 53 E-06 in/ D 696
Thermal Expansion in/.degree. F.
[0130] Vibra RIM 813 is a two component system available from
Crompton Corporation, Middlebury, Conn., comprising 813A (ISO) and
813B (POLYOL). In this regard, 813A is diphenylmethane 4,4'
diisocyanate (reaction product of a polyether with diphenylmethane
diisocyanate) and 813B is an alkylene glycol.
[0131] The physical properties of Vibra RIM A are as follows:
18 Physical Properties ATTRIBUTE SPECIFICATION % NCO 16.38-16.78
Viscosity 400-800 cps at 50 C with #2 spindle @ 20 rpm Color
Hellige Comparator: Gardner 3 max W/CL-620C-40
[0132] The physical properties of Vibra RIM B are noted below:
19 Physical Properties ATTRIBUTE SPECIFICATION Equivalent Weight
TBD - Theoretical 270.5 +/- 5 Viscosity 100-200 cps at 50 C (#2
spindle/20 rpm) Color WHITE - 4.84% PLASTICOLORS DR-10368 Moisture
0.10% Maximum
[0133] The overall plaque physical properties for the cover
materials is as follows:
20 ATTRIBUTE SPECIFICATION Plaque Material Shore D (peak) 39 s.g.
1.098 g/cc Flex. Mod. (ASTM D 790) 7920 psi 300% mod. (ASTM D 412)
2650 psi Young's mod. At 23 C (DMA) 75.5 MPa Shear mod. At 23 C
(DMA) 11.6 MPa
[0134] Other non-limiting examples of suitable RIM systems for use
in the exemplary embodiment are Bayflex7 elastomeric polyurethane
RIM systems, Baydur7 GS solid polyurethane RIM systems, Prism7
solid polyurethane RIM systems, all from Bayer Corp. (Pittsburgh,
Pa), SPECTRIM reaction moldable polyurethane and polyurea systems
from Dow Chemical USA (Midland, Mich.), and Elastolit SR systems
from BASF (Parsippany, N.J.).
[0135] The resulting cover comprises from about 5 to about 100
weight percent of polyurethane/polyurea based on the weight of the
cover. It may have pigments or dyes, accelerators, or UV
stabilizers added to it prior to molding. An example of a suitable
white pigment is titanium dioxide. Examples of suitable UV light
stabilizers are provided in commonly assigned U.S. Pat. No.
5,494,291, herein incorporated by reference in its entirety.
Furthermore, compatible polymeric materials can be added. For
example, when the component comprises polyurethane and/or polyurea,
such polymeric materials include polyurethane ionomers, polyamides,
etc. Fillers can also be incorporated into the golf ball component
as described above.
[0136] In a more preferred embodiment, the cover comprises a
relatively "soft" (low flex modulus) thermoset
polyurethane/polyurea material that is produced by RIM. The cover
layer is thin enough to produce the enhanced playability
characteristics desired without raising significant durability
issues (scuff, abrasion, cut, etc.). In this regard, a cover
thickness of from about 0.010 inches to about 0.040 inches is
desirable, including from about 0.010 inches to about 0.025 inches,
from about 0.014 inches to about 0.021 inches and about 0.014
inches to about 0.016 inches.
[0137] THE BALLThe resulting golf ball 10 of the present disclosure
has the desired characteristics noted above. It has a diameter of
1.680 inches or more, the minimum permitted by the U.S.G.A;
oversize balls may be produced if desired. In some embodiments, the
diameter of the golf ball is from 1.680 inches to about 1.780
inches. It weighs no more than 1.62 ounces. It has low driver spin
and good green-side spin. It has a high initial velocity of between
250 and 255 feet/sec. It has a COR of from about 0.770 to about
0.820, including from about 0.790 to about 0.816, and from about
0.805 to about 0.816. A more detailed description of a golf ball
having a high COR is set forth in U.S. Pat. No. 6,443,858, for a
Golf Ball With A High Coefficient Of Restitution, and in U.S. Pat.
No. 6,478,697 for a Golf Ball With A High Coefficient Of
Restitution, both of which are hereby incorporated by reference in
their entireties.
[0138] The surface geometry of the golf ball is preferably a
conventional dimple pattern such as disclosed in U.S. Pat. No.
6,213,898 for a Golf Ball With An Aerodynamic Surface On A
Polyurethane Cover, which pertinent parts are hereby incorporated
by reference. Alternatively, the surface geometry of the golf ball
has a non-dimple pattern such as disclosed in U.S. Pat. No.
6,290,615 for A Golf Ball Having Tubular Lattice Pattern, or
co-pending U.S. patent application Ser. No. 10/709,018, filed on
Apr. 7, 2004 for an Aerodynamic Surface Geometry Of A Golf Ball,
both of which pertinent parts are hereby incorporated by
reference.
[0139] Specifically, the arrangement and total number of dimples
are not critical and may be properly selected within ranges that
are well known. For example, the dimple arrangement may be an
octahedral, dodecahedral or icosahedral arrangement. The total
number of dimples is generally from about 250 to about 600, and
especially from about 300 to about 500. The dimples may also be
hexagonal in shape.
[0140] Additionally, one or more deep dimples may also be included
to enhance the molded golf ball construction process and/or
aerodynamics. A deep dimple is a dimple that extends through the
cover material to the intermediate or mantle layer and/or to the
core. For example, six extra deep hexagonal dimples may be included
to help to balance lift and drag. The extra deep dimples may also
be included to enhance the centering of the ball during ball
construction. Deep dimples are disclosed in U.S. Pat. No. 6,790,149
for a Golf Ball, which is hereby incorporated by reference in its
entirety.
[0141] In other embodiments, the golf ball is coated with a
durable, abrasion-resistant, relatively non-yellowing finish coat
or coats if necessary. The finish coat or coats may have some
optical brightener and/or pigment added to improve the brightness
of the finished golf ball. In one embodiment, from 0.001 to about
10% optical brightener may be added to one or more of the finish
coatings. If desired, optical brightener may also be added to the
cover materials. One type of preferred finish coatings are solvent
based urethane coatings known in the art. It is also contemplated
to provide a transparent outer coating or layer on the final
finished golf ball.
[0142] Golf balls also typically include logos and other markings
printed onto the dimpled spherical surface of the ball. Paint,
typically clear or white pigmented paint, is applied for the
purposes of protecting the cover and improving the outer appearance
before the ball is completed as a commercial product.
[0143] Specific embodiments of the disclosure will now be described
in detail. These examples are intended to be illustrative, and the
disclosure is not limited to the materials, conditions, or process
parameters set forth in these embodiments. All parts and
percentages are by weight unless otherwise indicated.
EXAMPLES
[0144] High compression multi-layer RIM golf balls (Examples A-J)
were produced according to the specifications set forth below and
compared to the controls noted.
Example 1
[0145]
21 A B C D E CALLAWAY .021 inch .021 inch .021 inch .016 inch .014
inch HX TOUR CALLAWAY cover cover cover cover cover 56 HX TOUR
TARGET CORE Inner Core No No No No No N/A Size (in) 1.550" 1.550"
1.550" 1.550" 1.550" Glebar Glebar Glebar Glebar Glebar Weight (g)
36.95 36.95 37.08 36.95 36.95 Instron 0.094 0.094 0.098 0.094 0.094
CoR 0.802 0.802 0.799 0.802 0.802 Specific 1.155 g/cc 1.155 g/cc
1.155 g/cc 1.160 g/cc 1.160 g/cc Gravity TARGET MANTLE Size (in)
1.640" 1.640" 1.640" 1.650" 1.654" N/A glebar glebar glebar glebar
glebar Weight (g) 42.55 42.55 42.55 42.55 Instron 0.0875 0.088
0.088 0.088 0.088 CoR 0.812 0.812 0.812 0.812 0.812 TARGET BALL
Size (in) 1.683 1.683 1.683 1.683 1.683 N/A Weight (g) 45.50 45.50
45.50 45.50 45.50 Instron (2 0.087 0.087 0.087 0.087 0.087 weeks)
CoR (2 weeks) 0.806 0.806 0.806 0.806 0.806 Dimple Pattern 5175
5175 5175 D5227 D5228 Actual Size (in) 1.550 1.550 1.550 1.550
1.550 N/A Core (0.0016) (0.0016) (0.0016) (.002) (.002) Weight (g)
36.88 36.88 36.88 37.04 37.04 (0.12) (0.12) (0.12) (.054) (.054)
Instron 0.092 0.092 0.092 .096 .096 (0.0014) (0.0014) (0.0014)
(.001) (.001) CoR 0.800 0.800 0.800 .799 .799 (0.0024) (0.0024)
(0.0024) (.002) (.002) Actual Size (in) 1.639 1.639 1.639 1.651
1.656 N/A Mantle (.0007) (.0007) (.0007) (.0063) (.0007) Weight (g)
42.45 42.45 42.45 43.37 43.68 (0.06) (0.06) (0.06) (.033) (.021)
Instron .087 .087 .087 .090 .089 (.0014) (.0014) (.0014) (.001)
(.001) CoR .809 .809 .809 .812 .812 (.0014) (.0014) (.0014) (.0017)
(.0009) Actual Ball Pole Size(in) 1.683 1.683 1.683 1.684 1.684
1.682 1.680 (.0010) (.0005) (.0006) (.0003) (.0006) (.0007) (.0011)
Equator Size 1.683 1.683 1.683 1.683 1.684 1.682 1.681 (in) (.0008)
(.0005) (.0011) (.0010) (.0006) (.0011) (.001) Weight (g) 45.49
45.48 45.42 45.56 45.5 45.50 45.51 (.05) (.04) (.05) (.02) (.04)
(0.12) (0.07) Instron .086 .087 .087 .088 .089 .094 .089 (.0016)
(.0015) (.0017) (.0017) (.0013) (.0015) (.0017) CoR .805 .803 .805
.811 .812 .807 .811 (.0026) (.0012) (.0032) (.0009) (.0019) (.0043)
(.0026) NezFactor 891 890 892 899 901 901 900 Total Spin USGA
Driver 10.0, 10.1, 10.1, 10.1, 10.0, 10.0, 257.3, 10.2, 258.7,
(deg, fps, RPM) 260.0, 259.1, 259.5, 259.9, 260.2, 2634 2448 2603
2543 2406 2554 2503 Pro Driver 9.6, 240.8, 9.6, 9.6, 9.7, 9.7, 9.7,
239.4, 9.6, 240.9, (deg, fps, RPM) 3081 240.4, 240.8, 240.7, 241.0,
3005 3043 3118 3046 3009 3058 Am. Driver 11.9, 11.9, 12.0, 11.9,
12.1, 11.9, 201.5, 11.9, 202.4, (deg, fps, RPM) 201.8, 201.7,
202.0, 202.3, 202.2, 3371 3408 3463 3549 3400 3401 3494 5-Iron
(deg, 14.0, 188.4, 13.9, 14.2, 14.2, 14.3, 14.4, 188.4, 14.4,
189.2, fps, RPM) 6300 188.3, 188.4, 188.9, 188.8, 5938 5826 6439
6240 6109 6036 P. Wedge (deg, 25.6, 25.6, 25.7, 25.9, 25.8, 25.9,
139.3, 25.9, 139.3, fps, RPM) 138.7, 138.7, 138.7, 138.9, 138.8,
9677 9833 10212 10213 10115 9903 9949 76 fps Chip 28.8, 75.8, 28.6,
28.8, 28.9, 29.0, 29.1, 76.3, 29.0, 76.6, (deg, fps, RPM) 7232
76.1, 76.1, 75.9, 76.0, 7166 7194 7375 7279 7188 7175 60 fps Chip
25.6, 61.0, 25.4, 25.7, 25.8, 25.9, 26.0, 61.2, 25.9, 61.1, (deg,
fps, RPM) 5973 60.9, 60.9, 60.9, 61.1, 5756 5842 6051 5914 5828
5818 Physical Testing Scuff Pass Pass Pass Pass Pass Pass Pass Cut
Pass Pass Pass Pass Pass Pass Pass Wet Barrel Pass Pass Pass Pass
Pass Pass Pass Weatherometer Pass Pass Pass Pass Pass Pass Pass
Cold Crack (6 No No No No No No Failures No Failures balls each to
5 Failures Failures Failures Failures Failures blows) Barrel (18
balls No No 1 @ No No NOT 1 @ 500 each to 500 Failures Failures 500
(1 Failures Failures TESTED blows) cover (1 failure cover also
failure noted also @ 500) noted @ 500) High Speed (18 1 each @ 1
each 1 each 1 @ 2 @ 196, NOT 1 each @ balls each to 138, 154, @103,
@ 97, 190 1 @ 200 TESTED 130, 152, 200 blows) 171, 189, 113, 152,
173, and and 190 137, 153, 199 2 @ and 152, 194 1 @ 155, 1 @
198
Example 2
[0146]
22 F G H I J .016 inch .016 inch .016 inch .016 inch .016 inch
cover cover cover cover cover TARGET Inner No No No No Yes CORE
Core Size (in) 1.550" 1.550" 1.550" 1.550" 1.520" Glebar Glebar
Glebar Glebar Glebar Weight (g) 37.05 37.05 37.05 37.05 35.03
Instron 0.0955 0.0955 0.0955 0.0965 0.0975 CoR 0.802 0.802 0.802
0.802 0.803 TARGET MANTLE Size (in) 1.650" 1.650" 1.650" 1.650"
1.650" glebar glebar glebar glebar glebar Weight (g) 43.35 43.35
43.35 43.35 43.35 Instron 0.0875 0.0875 0.0875 0.0875 0.0875 CoR
0.812 0.812 0.812 0.812 0.812 Size (in) 1.683 1.683 1.683 1.683
1.683 Weight (g) 45.50 45.50 45.50 45.50 45.50 Instron (2 0.087
0.087 0.087 0.087 0.087 weeks) CoR (2 0.810 0.810 0.813 0.813 0.813
weeks) Dimple 5227 5296 5227 5227 5227 Pattern TARGET Size (in)
.1550 .1550 1.550 1.550 1.519 BALL (.0032) (.0032) (.001) (.001)
(.001) Weight (g) 36.90 36.90 37.04 37.04 34.83 (.19) (.19) (.02)
(.02) (.07) Instron .0974 .0974 .095 .095 .095 (.0016) (.0016)
(.001) (.001) (.001) CoR .794 .794 .797 .797 .797 (.0026) (.0026)
(.0015) (.0015) (.0021) Actual Size (in) 1.651 1.651 1.651 1.650
1.650 Mantle (.0009) (.0009) (.0005) (.0005) (.0005) Weight (g)
43.36 43.36 43.4 43.4 43.0 (.06) (.06) (.09) (.06) (.06) Instron
.089 .089 .091 .089 .088 (.0015) (.0015) (.001) (.0007) (.0009) CoR
0.809 0.809 .809 .814 .815 (.0016) (.0011) (.0011) Random Size(in)
1.683 1.684 1.684 1.684 1.683 Statics (.0007) (.0005) (.0008)
(.0009) (.0007) Weight (g) 45.45 45.53 45.57 45.56 45.18 (.06)
(.04) (.06) (.06) (.06) Instron .089 .089 0.090 0.090 0.088 (.0015)
(.0013) CoR 0.812 0.810 0.812 0.815 0.817 NezFactor 901 899 902 905
905 Spin Size(in) NOT NOT 1.684 1.684 1.683 Statics APPLICABLE
APPLICABLE (.0008) (.0009) (.0007) Weight (g) 45.56 45.52 45.22
(.04) (.04) (.05) Instron .0892 .0882 .0870 (.0009) (.0013) (.0009)
CoR 0.812 0.814 0.813 NezFactor 900 902 900 F G H I K Total Spin HS
Driver (deg, 9.8, 9.9, 9.8, fps, RPM) 262, 262, 263, 2528 2573 2528
Pro Driver 10.2, 10.1, 10.2, (deg, fps, RPM) 240, 241, 241, 2824
2859 2881 Am. Driver 11.8, 11.8, 11.8, (deg, fps, RPM) 204, 204,
204, 3377 3322 3328 5-Iron (deg, 14.0, 14.1, 14.1, fps, RPM) 191,
191, 192, 6017 5982 6038 P. Wedge (deg, 25.7, 25.8, 25.8, fps, RPM)
141, 141, 141, 9339 9301 9292 76 fps Chip 28.9, 29.2, 28.9, (deg,
fps, RPM) 77, 77, 77, 7206 7092 7179 60 fps Chip 26.0, 26.1, 25.9,
(deg, fps, RPM) 61, 61, 60, 5585 5540 5521 Physical Testing Scuff
Pass Pass Pass Cut Pass Pass Pass Wet Barrel Pass Pass Pass
Weatherometer Pass Pass Pass Cold Crack (6 No No No balls each to 5
Failures Failures Failures blows) Barrel (18 balls No No No each to
500 Failures Failures Failures blows)
[0147] As noted, the above golf balls exhibited good distance with
acceptable playability properties.
[0148] The golf ball of the present disclosure has been described
with reference to exemplary embodiments. Obviously, modifications
and alterations will occur to others upon reading and understanding
the preceding detailed description. It is intended that the present
disclosure be construed as including all such modifications and
alterations insofar as they come within the scope of the appended
claims or the equivalents thereof.
* * * * *