U.S. patent application number 13/613483 was filed with the patent office on 2013-05-23 for two-toned color golf ball having colored component covered by opaque and translucent cover parts.
The applicant listed for this patent is Matthew F. Hogge, William E. Morgan. Invention is credited to Matthew F. Hogge, William E. Morgan.
Application Number | 20130130841 13/613483 |
Document ID | / |
Family ID | 48427474 |
Filed Date | 2013-05-23 |
United States Patent
Application |
20130130841 |
Kind Code |
A1 |
Morgan; William E. ; et
al. |
May 23, 2013 |
TWO-TONED COLOR GOLF BALL HAVING COLORED COMPONENT COVERED BY
OPAQUE AND TRANSLUCENT COVER PARTS
Abstract
The present invention is directed to a golf ball possessing an
overall unique and perceptively pleasing golf ball having an
overall color appearance of two colors wherein more than one golf
ball layer/component contributes to the bi-color appearance without
the need to position and align the outer layers/components in
relation to the inner layer/component.
Inventors: |
Morgan; William E.;
(Barrington, RI) ; Hogge; Matthew F.; (Plymouth,
MA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Morgan; William E.
Hogge; Matthew F. |
Barrington
Plymouth |
RI
MA |
US
US |
|
|
Family ID: |
48427474 |
Appl. No.: |
13/613483 |
Filed: |
September 13, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13373599 |
Nov 21, 2011 |
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13613483 |
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13374197 |
Dec 15, 2011 |
8308587 |
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13373599 |
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13374198 |
Dec 15, 2011 |
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13374197 |
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Current U.S.
Class: |
473/378 |
Current CPC
Class: |
A63B 37/0063 20130101;
A63B 37/0024 20130101; A63B 37/0043 20130101; A63B 2037/0079
20130101; A63B 43/008 20130101; A63B 37/0092 20130101; A63B 37/0096
20130101; A63B 37/0049 20130101; A63B 37/0077 20130101; A63B
37/0087 20130101; A63B 37/0006 20130101; A63B 37/0078 20130101;
A63B 45/00 20130101; A63B 37/0074 20130101; A63B 37/0075 20130101;
A63B 37/0018 20130101; A63B 37/0003 20130101 |
Class at
Publication: |
473/378 |
International
Class: |
A63B 37/12 20060101
A63B037/12 |
Claims
1. A golf ball having an overall bi-color color appearance
comprising: a core and a cover disposed about the core; the core
having color A; the cover comprising a cover portion CP1 and a
cover portion CP2, wherein CP1 is opaque and has color B and CP2 is
translucent and has color D such that D.noteq.A; and wherein the
golf ball has an overall color appearance comprising SA1 and SA2,
wherein SA1 comprises an entire surface area of CP1 and SA2
comprises an entire surface area of CP2 such that SA1 is opaque and
has a color appearance of the color B and SA2 has a color
appearance of a color E wherein E=A+D.
2. The golf ball of claim 1, wherein A=B.
3. The golf ball of claim 1, wherein A.noteq.B.
4. The golf ball of claim 1, wherein B has a hue h.sub.1 and D has
a hue h.sub.2 such that h.sub.1=h.sub.2.
5. The golf ball of claim 1, wherein B.noteq.D.
6. The golf ball of claim 1, wherein the surface areas of CP1 and
CP2 are substantially similar.
7. A golf ball having an overall bi-color color appearance
comprising: a core and a cover disposed about the core; the core
having color A; the cover comprising a cover portion CP1 and a
cover portion CP2, CP1 and CP2 having a boundary L, wherein CP1 is
opaque and has color B and CP2 is translucent and has color D such
that D.noteq.A; and wherein the golf ball has an overall color
appearance comprising two colors SA1 and SA2 that have the boundary
L, such that SA1 is opaque and has a color appearance of the color
B and SA2 has a color appearance of a color E wherein E=A+D.
8. The golf ball of claim 7, wherein boundary L is planar.
9. The golf ball of claim, 7, wherein boundary L is nonplanar.
10. The golf ball of claim 7, wherein CP1 and CP2 have
substantially similar surface areas.
11. The golf ball of claim 7, wherein A=B.
12. The golf ball of claim 7, wherein A.noteq.B.
13. The golf ball of claim 7, wherein B has a hue h.sub.1 and D has
a hue h.sub.2 such that h.sub.1=h.sub.2.
14. The golf ball of claim 7, wherein B.noteq.D.
15. A golf ball having an overall bi-color color appearance
comprising: a core, a cover disposed about the core and an
intermediate layer disposed between the core and the cover; the
intermediate layer having color A; the cover comprising a cover
portion CP1 and a cover portion CP2, wherein CP1 is opaque and has
color B and CP2 is translucent and has color D such that D.noteq.A;
and wherein the golf ball has an overall color appearance
comprising SA1 and SA2, wherein SA1 comprises an entire surface
area of CP1 and SA2 comprises an entire surface area of CP2 such
that SA1 is opaque and has a color appearance of the color B and
SA2 has a color appearance of a color E wherein E=A+D.
16. The golf ball of claim 15, wherein CP1 and CP2 have
substantially similar surface areas.
17. The golf ball of claim 15, wherein A=B.
18. The golf ball of claim 15, wherein A.noteq.B.
19. The golf ball of claim 15, wherein B has a hue h.sub.1 and D
has a hue h.sub.2 such that h.sub.1=h.sub.2.
20. The golf ball of claim 15, wherein B.noteq.D.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of each of the
following co-pending applications: U.S. application Ser. No.
13/373,599, filed on Nov. 21, 2011; U.S. application Ser. No.
13/374,197, filed on Dec. 15, 1011; and U.S. application Ser. No.
13/374,198, filed on Dec. 15, 1011; and the disclosure of each is
incorporated by reference herein in its entirety.
FIELD OF THE INVENTION
[0002] The invention relates generally to golf balls incorporating
color, pigments dyes, tints and color effects in golf ball
components to optimize golf ball appearance and golfer performance
on the green.
BACKGROUND OF THE INVENTION
[0003] Golf balls, whether of solid or wound construction,
generally include a core and at least a cover or outer coating. The
properties of a conventional solid ball may be modified by altering
the typical single layer core and single cover layer construction
to provide a ball having at least one mantle layer disposed between
the cover and the core. The core may be solid or liquid-filled, and
may be formed of a single layer or one or more layers. Covers, in
addition to cores, may also be formed of one or more layers. These
multi-layer cores and covers are sometimes known as "dual core" and
"dual cover" golf balls, respectively. Additionally, many golf
balls contain one or more intermediate layers that can be of solid
construction or may be formed of a tensioned elastomeric winding,
which are referred to as wound balls. One piece golf balls are even
available. The difference in play characteristics resulting from
these different types of constructions can be quite significant.
The playing characteristics of multi-layer balls, such as spin and
compression, can be tailored by varying the properties of one or
more of these intermediate and/or cover layers.
[0004] Moreover, color in a golf ball is a visually distinguishing
feature. In this regard, golf balls having an overall color
appearance of two predominant colors are known. One such prior golf
ball incorporates two differently colored opaque cover halves.
Another prior bi-colored golf ball incorporates two differently
colored core halves and a uniformly clear cover. However, in each
of these prior two-colored golf balls, overall color appearance is
determined by a single layer.
[0005] In related co-pending co-owned U.S. applications Ser. Nos.
13/373,599, 13/374,197, and 13/374,198, a unique two color overall
golf ball color appearance is achieved wherein the golf ball has
inner and outer layers each which contribute substantially to the
golf ball's overall color appearance. Further, as seen in FIG. 2B
of these applications, each layer has at least two color regions
and the inner and outer layers are strategically positioned and
aligned in relation to each other in order to create the overall
bi-color golf ball color appearance. However, there remains a need
for golf balls wherein an overall two color appearance is achieved
via color contribution by both inner and outer layers without
having to position and align the inner and outer layers/components
in relation to each other--as this would reduce manufacturing
costs. The present invention addresses and solves this problem.
SUMMARY OF THE INVENTION
[0006] Accordingly, the invention is related to a golf ball having
an overall color appearance of two predominant colors wherein more
than one layer/component contributes to the bi-colored appearance
without the need to align the color contributing layers/components.
In one embodiment of the invention, the golf ball having an overall
bi-color color appearance comprises: a core and a cover disposed
about the core; the core having color A; the cover comprising a
cover portion CP1 and a cover portion CP2, wherein CP1 is opaque
and has color B and CP2 is translucent and has color D such that
DSA; and wherein the golf ball has an overall color appearance
comprising SA1 and SA2, wherein SA1 comprises an entire surface
area of CP1 and SA2 comprises an entire surface area of CP2 such
that SA1 is opaque and has a color appearance of the color B and
SA2 has a color appearance of a color E wherein E=A+D.
[0007] In one embodiment, A=B. That is, color A is exactly the same
as or identical to color B. In another embodiment, A.noteq.B. That
is color A is different than color B in at least one way such as
having a different hue, saturation or chroma for example.
[0008] In one embodiment, B has a hue h.sub.1 and D has a hue
h.sub.2 such that h.sub.1=h.sub.2. In another embodiment,
B.noteq.D.
[0009] In one embodiment, the surface areas of CP1 and CP2 are
substantially similar.
[0010] In another embodiment, the golf ball having an overall
bi-color color appearance comprises: a core and a cover disposed
about the core; the core having color A; the cover comprising a
cover portion CP1 and a cover portion CP2, CP1 and CP2 having a
boundary L, wherein CP1 is opaque and has color B and CP2 is
translucent and has color D such that D.noteq.A; and wherein the
golf ball has an overall color appearance comprising two colors SA1
and SA2 that have the boundary L, such that SA1 is opaque and has a
color appearance of the color B and SA2 has a color appearance of a
color E wherein E=A+D.
[0011] In one embodiment, boundary L is planar. In another
embodiment, boundary L is nonplanar.
[0012] In one embodiment, CP1 and CP2 have substantially similar
surface areas.
[0013] In one embodiment, A=B. In another embodiment,
A.noteq.B.
[0014] In one embodiment, B has a hue h.sub.1 and D has a hue
h.sub.2 such that h.sub.1=h.sub.2 while their respective
saturations and/or chromas differ.
[0015] In another embodiment, B.noteq.D.
[0016] In yet another embodiment, the golf ball having an overall
bi-color color appearance comprises: a core, a cover disposed about
the core and an intermediate layer disposed between the core and
the cover; the intermediate layer having color A; the cover
comprising a cover portion CP1 and a cover portion CP2, wherein CP1
is opaque and has color B and CP2 is translucent and has color D
such that D.noteq.A; and wherein the golf ball has an overall color
appearance comprising SA1 and SA2, wherein SA1 comprises an entire
surface area of CP1 and SA2 comprises an entire surface area of CP2
such that SA1 is opaque and has a color appearance of the color B
and SA2 has a color appearance of a color E wherein E=A+D.
[0017] In one embodiment, A=B. In another embodiment,
A.noteq.B.
[0018] In one embodiment, A=B. B has a hue h.sub.1 and D has a hue
h.sub.2 such that h.sub.1=h.sub.2.
[0019] In another embodiment, B.noteq.D.
[0020] In one embodiment, the surface areas of CP1 and CP2 are
substantially similar. Herein, the term "hue" shall refer to any
color within the spectrum of visible light such as blue, red,
yellow, purple, orange, green, etc. The symbol ".noteq.", when used
herein in connection with the word color or colors shall refer to
two colors which are different in that they have different hues,
chromas and/or saturations or are otherwise visually
distinguishable by the human viewing eye. For example, where color
A.noteq.color B, these colors are in some way visually
distinguishable by the human viewing eye. In turn, the symbol "="
as used herein in connection with the word color or colors shall
refer to two colors which are visually not distinguishable by the
human viewing eye.
[0021] Golf balls of the invention may be manufactured according to
any method or process known in the art suitable for mating two
cover half shells about an inner layer such as an inner cover
layer, intermediate layer outer core layer, or solid core.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1 is a side view depicting how a golf ball of the
invention may be formed/constructed according to one embodiment of
the invention; and
[0023] FIGS. 2A, 2B, and 2C are side views of an alternative
embodiment of golf balls having an overall color appearance of two
colors.
DETAILED DESCRIPTION
[0024] The term "overall color appearance", as used herein, refers
to the overall color appearance of the golf ball as perceived by
the human eye viewing the entire golf ball surface. For example, a
golf ball of the invention has an overall golf ball appearance
comprised of two different color regions even though the golf
ball's inner layer is comprised of one different color the
overlying outer layer is comprised of two additional differently
colored regions. Such a golf ball construction is achieved by
forming the outer layer having two differently colored regions
about the inner layer comprising a single color without the
necessity of aligning the color of the inner layer with the
respective colors of the cover halves or half shells.
[0025] Non-limiting examples of the two-toned or bi-color golf
balls of the invention are as follows. Herein, like numbers and
letters used in each figure represent like elements or parts.
[0026] Referring to FIG. 1, in one aspect of the invention, half
shells 14 and 16 have surface areas that are substantially similar.
Half shells 14 and 16, having colors 15 and 17, respectively, are
formed about core 12 having color 13. Half shell 14 is opaque and
half shell 16 is translucent. Core 12 having color 13 participates
in and/or contributes to the golf ball's overall color appearance
through translucent half shell 16. Accordingly, the overall color
appearance of finished golf ball 14 is comprised of two different
colors 15 and 18, wherein color 18 comprises contributing colors 13
and 17. A golf ball of FIG. 1 achieves an overall color appearance
of two colors notwithstanding how half shells 14,16 are positioned
and aligned about core 12 having color 13.
[0027] FIG. 2B represents an embodiment wherein the inner layer
comprises two color regions and the outer layer is strategically
positioned and aligned about the inner layer to create a golf ball
having an overall color appearance of two colors. In FIG. 2B, golf
ball 1D includes inner layer 2 and outer layer 3, each of which
participate in and/or contribute to the golf ball's overall color
appearance. Inner layer 2 comprises two different color regions 4
and 5. Color region 4 has a greater surface area than color region
5. Meanwhile, outer layer 3 includes differently colored color
regions 6 and 7 which have the same surface area, are disposed
about inner layer 2, and are bounded by boundary 8. Color region 6
is translucent, color region 7 is opaque, and outer layer 3 is
positioned and aligned about inner layer 2 such that boundary 8
does not intersect color region 5. In this embodiment, the overall
color appearance of golf ball 1D is comprised of 2 different
colors.
[0028] However, this golf ball would produce a different overall
appearance if color region 6 is opaque and color region 7 is
translucent--in that case, the color appearance of golf ball 1D
would be that of golf ball 1E in FIG. 2C--comprised of 3 different
colors. Furthermore, the golf ball of FIG. 2B would likewise
produce a different overall color appearance, namely of three
colors, if the inner and outer layers are positioned and aligned as
in FIG. 2A. In FIG. 2A, golf ball 1C includes inner layer 2 and
outer layer 3, each of which participate in and/or contribute to
the golf ball's overall color appearance. Inner layer 2 comprises
two different color regions 4 and 5. Color region 4 has a greater
surface area than color region 5. Meanwhile, outer layer 3 includes
differently colored color regions 6 and 7 which have the same
surface area, are disposed about inner layer 2 and are bounded by
boundary 8. Color region 6 is translucent, color region 7 is
opaque, and outer layer 3 is positioned and aligned about inner
layer 2 such that boundary 8 intersects color region 5. In this
embodiment, the overall color appearance of golf ball 1C is
comprised of 3 different colors. The golf ball would have a similar
overall appearance if color region 6 is opaque and color region 7
is translucent.
[0029] Herein, an inner layer may comprise, for example, a core
surface, an outer core layer, an intermediate layer, a mantle layer
or an inner cover layer. Meanwhile, an outer layer may comprise a
cover layer for example.
[0030] The cores in golf balls of this invention may be solid,
semi-solid, hollow, fluid-filled, or powder-filled. Typically, the
cores are solid and made from rubber compositions containing at
least a base rubber, free-radical initiator agent, cross-linking
co-agent, and fillers. Golf balls having various constructions may
be made in accordance with this invention. For example, golf balls
having three-piece, four-piece, and five-piece constructions with
dual or three-layered cores and cover materials may be made The
term, "layer" as used herein means generally any spherical portion
of the golf ball. More particularly, in one version, a three-piece
golf ball comprising a core and a "dual-cover" is made. In another
version, a four-piece golf ball comprising a dual-core and
"dual-cover" is made. The dual-core includes an inner core (center)
and surrounding outer core layer. The dual-cover includes inner
cover and outer cover layers. In yet another construction, a
five-piece golf ball having a dual-core, intermediate layer, and
dual-cover is made. In still another embodiment, a four piece golf
ball comprises a core and a three layer cover. The term
"semi-solid" as used herein refers to a paste, a gel or the
like.
[0031] As used herein, the term, "intermediate layer" means a layer
of the ball disposed between the core and cover. The intermediate
layer may be considered an outer core layer, or inner cover layer,
or any other layer disposed between the inner core and outer cover
of the ball. The intermediate layer also may be referred to as a
casing or mantle layer. The diameter and thickness of the different
layers along with properties such as hardness and compression may
vary depending upon the construction and desired playing
performance properties of the golf ball and as specified
herein.
[0032] The inner core of the golf ball may comprise a polybutadiene
rubber material. In one embodiment, the ball contains a single core
formed of the polybutadiene rubber composition. In a second
embodiment, the ball contains a dual-core comprising an inner core
(center) and surrounding outer core layer. In yet another version,
the golf ball contains a multi-layered core comprising an inner
core, intermediate core layer, and outer core layer.
[0033] In general, polybutadiene is a homopolymer of 1,3-butadiene.
Catalysts of the 1,3-butadiene monomer enables growth of the
polymer chain to form a polybutadiene polymer having a desired
molecular weight. Any suitable catalyst may be used to synthesize
the polybutadiene rubber depending upon the desired properties.
Normally, a transition metal complex (for example, neodymium,
nickel, or cobalt) or an alkyl metal such as alkyllithium is used
as a catalyst. Other catalysts include, but are not limited to,
aluminum, boron, lithium, titanium, and combinations thereof. The
catalysts produce polybutadiene rubbers having different chemical
structures. In a cis-bond configuration, the main internal polymer
chain of the polybutadiene appears on the same side of the
carbon-carbon double bond contained in the polybutadiene. In a
trans-bond configuration, the main internal polymer chain is on
opposite sides of the internal carbon-carbon double bond in the
polybutadiene. The polybutadiene rubber can have various
combinations of cis- and trans-bond structures. A preferred
polybutadiene rubber has a 1,4 cis-bond content of at least 40%,
preferably greater than 80%, and more preferably greater than 90%.
In general, polybutadiene rubbers having a high 1,4 cis-bond
content have high tensile strength. The polybutadiene rubber may
have a relatively high or low Mooney viscosity.
[0034] Examples of commercially available polybutadiene rubbers
that can be used in accordance with this invention, include, but
are not limited to, BR 01 and BR 1220, available from BST
Elastomers of Bangkok, Thailand; SE BR 1220LA and SE BR1203,
available from DOW Chemical Co of Midland, Mich.; BUDENE 1207,
1207s, 1208, and 1280 available from Goodyear, Inc of Akron, Ohio;
BR 01, 51 and 730, available from Japan Synthetic Rubber (JSR) of
Tokyo, Japan; BUNA CB 21, CB 22, CB 23, CB 24, CB 25, CB 29 MES, CB
60, CB Nd 60, CB 55 NF, CB 70 B, CB KA 8967, and CB 1221, available
from Lanxess Corp. of Pittsburgh. Pa.; BR1208, available from LG
Chemical of Seoul, South Korea; UBEPOL BR130B, BR150, BR150B,
BR150L, BR230, BR360L, BR710, and VCR617, available from UBE
Industries, Ltd. of Tokyo, Japan; EUROPRENE NEOCIS BR 60, INTENE 60
AF and P30AF, and EUROPRENE BR HV80, available from Polimeri Europa
of Rome, Italy; AFDENE 50 and NEODENE BR40, BR45, BR50 and BR60,
available from Karbochem (PTY) Ltd. of Bruma, South Africa; KBR 01,
NdBr 40, NdBR-45, NdBr 60, KBR 710S, KBR 710H, and KBR 750,
available from Kumho Petrochemical Co., Ltd. Of Seoul, South Korea;
DIENE 55NF, 70AC, and 320 AC, available from Firestone Polymers of
Akron, Ohio; and PBR-Nd Group II and Group III, available from
Nizhnekamskneftekhim, Inc. of Nizhnekamsk, Tartarstan Republic.
[0035] Suitable polybutadiene rubbers for blending with the base
rubber may include BUNA.RTM. CB22, BUNA.RTM. CB23 and BUNA.RTM.
CB24, BUNA .RTM. 1203G1, 1220, 1221, and BUNA.RTM. CBNd-40,
commercially available from LANXESS Corporation; BSTE BR-1220
available from BST Elastomers Co. LTD; UBEPOL.RTM. 360L and
UBEPOL.RTM. 150L and UBEPOL-BR rubbers, commercially available from
UBE Industries, Ltd. of Tokyo, Japan; Budene 1207, 1208 and 1280,
commercially available from Goodyear of Akron, Ohio; SE BR-1220,
commercially available from Dow Chemical Company; Europrene.RTM.
NEOCIS.RTM. BR 40 and BR 60, commercially available from Polimeri
Europa; and BR 01, BR 730, BR 735, BR 11, and BR 51, commercially
available from Japan Synthetic Rubber Co., Ltd; and KARBOCHEM.RTM.
Neodene 40, 45, and 60, commercially available from Karbochem.
[0036] The base rubber may further include polyisoprene rubber,
natural rubber, ethylene-propylene rubber, ethylene-propylene diene
rubber, styrene-butadiene rubber, and combinations of two or more
thereof. Another preferred base rubber is polybutadiene optionally
mixed with one or more elastomers such as polyisoprene rubber,
natural rubber, ethylene propylene rubber, ethylene propylene diene
rubber, styrene-butadiene rubber, polystyrene elastomers,
polyethylene elastomers, polyurethane elastomers, polyurea
elastomers, acrylate rubbers, polyoctenamers, metallocene-catalyzed
elastomers, and plastomers. As discussed further below, highly
neutralized acid copolymers (HNPs), as known in the art, also can
be used to form the core layer as part of the blend. Such
compositions will provide increased flexural modulus and toughness
thereby improving the golf ball's performance including its impact
durability.
[0037] The base rubber typically is mixed with at least one
reactive cross-linking co-agent to enhance the hardness of the
rubber composition. Suitable co-agents include, but are not limited
to, unsaturated carboxylic acids and unsaturated vinyl compounds. A
preferred unsaturated vinyl compound is trimethylolpropane
trimethacrylate. The rubber composition is cured using a
conventional curing process. Suitable curing processes include, for
example, peroxide curing, sulfur curing, high-energy radiation, and
combinations thereof. In one embodiment, the base rubber is
peroxide cured. Organic peroxides suitable as free-radical
initiators include, for example, dicumyl peroxide;
n-butyl-4,4-di(t-butylperoxy) valerate;
1,1-di(t-butylperoxy)3,3,5-trimethylcyclohexane;
2,5-dimethyl-2,5-di(t-butylperoxy) hexane; di-t-butyl peroxide;
di-t-amyl peroxide; t-butyl peroxide; t-butyl cumyl peroxide;
2,5-dimethyl-2,5-di(t-butylperoxy)hexyne-3;
di(2-t-butyl-peroxyisopropyl)benzene; dilauroyl peroxide; dibenzoyl
peroxide; t-butyl hydroperoxide; and combinations thereof.
Cross-linking agents are used to cross-link at least a portion of
the polymer chains in the composition. Suitable cross-linking
agents include, for example, metal salts of unsaturated carboxylic
acids having from 3 to 8 carbon atoms; unsaturated vinyl compounds
and polyfunctional monomers (for example, trimethylolpropane
trimethacrylate); phenylene bismaleimide; and combinations thereof.
In a particular embodiment, the cross-linking agent is selected
from zinc salts of acrylates, diacrylates, methacrylates, and
dimethacrylates. In another particular embodiment, the
cross-linking agent is zinc diacrylate ("ZDA"). Commercially
available zinc diacrylates include those selected from Cray Valley
Resource Innovations Inc. Other elastomers known in the art may
also be added, such as other polybutadiene rubbers, natural rubber,
styrene butadiene rubber, and/or isoprene rubber in order to
further modify the properties of the core. When a mixture of
elastomers is used, the amounts of other constituents in the core
composition are typically based on 100 parts by weight of the total
elastomer mixture.
[0038] Thermoplastic elastomers (TPE) may also be used to modify
the properties of the core layers, or the uncured core layer stock
by blending with the uncured rubber. These TPEs include natural or
synthetic balata, or high trans-polyisoprene, high
trans-polybutadiene, or any styrenic block copolymer, such as
styrene ethylene butadiene styrene, styrene-isoprene-styrene, etc.,
a metallocene or other single-site catalyzed polyolefin such as
ethylene-octene, or ethylene-butene, or thermoplastic polyurethanes
(TPU), including copolymers, e.g. with silicone. Other suitable
TPEs for blending with the thermoset rubbers of the present
invention include PEBAX.RTM., which is believed to comprise
polyether amide copolymers, HYTREL.RTM., which is believed to
comprise polyether ester copolymers, thermoplastic urethane, and
KRATON.RTM., which is believed to comprise styrenic block
copolymers elastomers. Any of the TPEs or TPUs above may also
contain functionality suitable for grafting, including maleic acid
or maleic anhydride. Any of the Thermoplastic Vulcanized Rubbers
(TPV) such as Santoprene.RTM. or Vibram.RTM. or ETPV.RTM. can be
used along with a present invention. In one embodiment, the TPV has
a thermoplastic as a continuous phase and a cross-linked rubber
particulate as a dispersed (or discontinuous) phase. In another
embodiment, the TPV has a cross-linked phase as a continuous phase
and a thermoplasttic as a dispersed (or discontinuous) phase to
provide reduced loss in elasticity in order to improve the
resiliency of the golf ball.
[0039] The rubber compositions also may contain "soft and fast"
agents such as a halogenated organosulfur, organic disulfide, or
inorganic disulfide compounds. Particularly suitable halogenated
organosulfur compounds include, but are not limited to, halogenated
thiophenols. Preferred organic sulfur compounds include, but not
limited to, pentachlorothiophenol ("PCTP") and a salt of PCTP. A
preferred salt of PCTP is ZnPCTP. A suitable PCTP is sold by the
Struktol Company (Stow, Ohio) under the tradename, A95. ZnPCTP is
commercially available from EchinaChem (San Francisco, Calif.).
These compounds also may function as cis-to-trans catalysts to
convert some cis bonds in the polybutadiene to trans bonds.
Antioxidants also may be added to the rubber compositions to
prevent the breakdown of the elastomers. Other ingredients such as
accelerators (for example, tetra methylthiuram), processing aids,
dyes and pigments, wetting agents, surfactants, plasticizers, as
well as other additives known in the art may be added to the rubber
composition.
[0040] The core may be formed by mixing and forming the rubber
composition using conventional techniques. These cores can be used
to make finished golf balls by surrounding the core with outer core
layer(s), intermediate layer(s), and/or cover materials as
discussed further below. In another embodiment, the cores can be
formed using highly neutralized polymer (HNP) compositions as
disclosed in U.S. Pat. Nos. 6,756,436, 7,030,192, 7,402,629, and
7,517,289. The cores from the highly neutralized polymer
compositions can be further cross-linked using any free-radical
initiation sources including radiation sources such as gamma or
electron beam as well as chemical sources such as peroxides and the
like.
[0041] Golf balls made in accordance with this invention can be of
any size, although the USGA requires that golf balls used in
competition have a diameter of at least 1.68 inches and a weight of
no greater than 1.62 ounces. For play outside of USGA competition,
the golf balls can have smaller diameters and be heavier.
[0042] A wide variety of thermoplastic or thermosetting materials
can be employed in forming the core, cover layers, or both. These
materials include for example, olefin-based copolymer ionomer
resins (for example, Surlyn.RTM. ionomer resins and DuPont.RTM. HPF
1000 and HPF 2000, as well as blends of
Surlyn.RTM.7940/Surlyn.RTM.8940 or Surlyn.RTM.8150/Surlyn.RTM.9150
commercially available from E. I. du Pont de Nemours and Company;
lotek.RTM. ionomers, commercially available from ExxonMobil
Chemical Company; Amplify.RTM. IO ionomers of ethylene acrylic acid
copolymers, commercially available from The Dow Chemical Company;
and Clarix.RTM. ionomer resins, commercially available from A.
Schulman Inc.); polyurethanes; polyureas; copolymers and hybrids of
polyurethane and polyurea; polyethylene, including, for example,
low density polyethylene, linear low density polyethylene, and high
density polyethylene; polypropylene; rubber-toughened olefin
polymers; acid copolymers, for example, poly(meth)acrylic acid,
which do not become part of an ionomeric copolymer; plastomers;
flexomers; styrene/butadiene/styrene block copolymers;
styrene/ethylene-butylene/styrene block copolymers; dynamically
vulcanized elastomers; copolymers of ethylene and vinyl acetates;
copolymers of ethylene and methyl acrylates; polyvinyl chloride
resins; polyamides, poly(amide-ester) elastomers, and graft
copolymers of ionomer and polyamide including, for example,
Pebax.RTM. thermoplastic polyether block amides, commercially
available from Arkema Inc; cross-linked trans-polyisoprene and
blends thereof; polyester-based thermoplastic elastomers, such as
Hytrel.RTM., commercially available from E. I. du Pont de Nemours
and Company; polyurethane-based thermoplastic elastomers, such as
Elastollan.RTM., commercially available from BASF; synthetic or
natural vulcanized rubber; and combinations thereof.
[0043] In fact, any of the core, intermediate layer and/or cover
layers may include the following materials:
[0044] (1) Polyurethanes, such as those prepared from polyols and
diisocyanates or polyisocyanates and/or their prepolymers;
[0045] (2) Polyureas; and
[0046] (3) Polyurethane-urea hybrids, blends or copolymers
comprising urethane and urea segments.
[0047] Polyurethanes and polyureas may constitute either thermoset
or thermoplastic compositions, depending on the type of
crosslinking bond that is created during formation of the
composition. When a polyurethane or polyurea prepolymer is cross
linked with a polyfunctional curing agent, covalent bonding occurs,
resulting in a thermoset composition. In contrast, polyurethanes
and polyureas will be thermoplastic where the crosslinking is due,
for example, to hydrogen bonding, resulting in weaker bonds which
may be broken upon heating the composition. This distinction
explains why thermoset materials generally may not be recycled or
reformed into a different shape by heating (at least not easily),
whereas thermoplastic materials may so be. The process for
manufacturing a golf ball according to the invention is
particularly well-suited for forming golf balls having a
combination of a very thin, thermoplastic outer cover and a
thermoset inner cover having a thickness greater than that of the
outer cover layer, providing both COR stability and
playability.
[0048] Suitable polyurethane compositions comprise a reaction
product of at least one polyisocyanate and at least one curing
agent. The curing agent can include, for example, one or more
polyamines, one or more polyols, or a combination thereof. The
polyisocyanate can be combined with one or more polyols to form a
prepolymer, which is then combined with the at least one curing
agent. Thus, the polyols described herein are suitable for use in
one or both components of the polyurethane material, i.e., as part
of a prepolymer and in the curing agent. Suitable polyurethanes are
described in U.S. Patent Application Publication No. 2005/0176523,
which is incorporated by reference in its entirety.
[0049] Any polyisocyanate available to one of ordinary skill in the
art is suitable for use according to the invention. Exemplary
polyisocyanates include, but are not limited to,
4,4'-diphenylmethane diisocyanate (MDI); polymeric MDI;
carbodiimide-modified liquid MDI; 4,4'-dicyclohexylmethane
diisocyanate (H.sub.12MDI); p-phenylene diisocyanate (PPDI);
m-phenylene diisocyanate (MPDI); toluene diisocyanate (TDI);
3,3'-dimethyl-4,4'-biphenylene diisocyanate;
isophoronediisocyanate; 1,6-hexamethylene diisocyanate (HDI);
naphthalene diisocyanate; xylene diisocyanate; p-tetramethylxylene
diisocyanate; m-tetramethylxylene diisocyanate; ethylene
diisocyanate; propylene-1,2-diisocyanate;
tetramethylene-1,4-diisocyanate; cyclohexyl diisocyanate;
dodecane-1,12-diisocyanate; cyclobutane-1,3-diisocyanate;
cyclohexane-1,3-diisocyanate; cyclohexane-1,4-diisocyanate;
1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane; methyl
cyclohexylene diisocyanate; triisocyanate of HDI; triisocyanate of
2,4,4-trimethyl-1,6-hexane diisocyanate; tetracene diisocyanate;
napthalene diisocyanate; anthracene diisocyanate; isocyanurate of
toluene diisocyanate; uretdione of hexamethylene diisocyanate; and
mixtures thereof. Polyisocyanates are known to those of ordinary
skill in the art as having more than one isocyanate group, e.g.,
di-isocyanate, tri-isocyanate, and tetra-isocyanate. Preferably,
the polyisocyanate includes MDI, PPDI, TDI, or a mixture thereof,
and more preferably, the polyisocyanate includes MDI. It should be
understood that, as used herein, the term MDI includes
4,4'-diphenylmethane diisocyanate, polymeric MDI,
carbodiimide-modified liquid MDI, and mixtures thereof.
Additionally, the prepolymers synthesized from these diisocyanates
may be "low free monomer," understood by one of ordinary skill in
the art to have lower levels of "free" isocyanate monomers,
typically less than about 0.1% free isocyanate. Examples of "low
free monomer" prepolymers include, but are not limited to Low Free
Monomer MDI prepolymers, Low Free Monomer TDI prepolymers, and Low
Free Monomer PPDI prepolymers.
[0050] Any polyol available to one of ordinary skill in the art is
suitable for use according to the invention. Exemplary polyols
include, but are not limited to, polyether polyols,
hydroxy-terminated polybutadiene (including partially/fully
hydrogenated derivatives), polyester polyols, polycaprolactone
polyols, and polycarbonate polyols. In one preferred embodiment,
the polyol includes polyether polyol. Examples include, but are not
limited to, polytetramethylene ether glycol (PTMEG), polyethylene
propylene glycol, polyoxypropylene glycol, and mixtures thereof.
The hydrocarbon chain can have saturated or unsaturated bonds and
substituted or unsubstituted aromatic and cyclic groups.
Preferably, the polyol of the present invention includes PTMEG.
[0051] In another embodiment, polyester polyols are included in the
polyurethane material. Suitable polyester polyols include, but are
not limited to, polyethylene adipate glycol; polybutylene adipate
glycol; polyethylene propylene adipate glycol;
o-phthalate-1,6-hexanediol; poly(hexamethylene adipate) glycol; and
mixtures thereof. The hydrocarbon chain can have saturated or
unsaturated bonds, or substituted or unsubstituted aromatic and
cyclic groups.
[0052] In another embodiment, polycaprolactone polyols are included
in the materials of the invention. Suitable polycaprolactone
polyols include, but are not limited to, 1,6-hexanediol-initiated
polycaprolactone, diethylene glycol initiated polycaprolactone,
trimethylol propane initiated polycaprolactone, neopentyl glycol
initiated polycaprolactone, 1,4-butanediol-initiated
polycaprolactone, and mixtures thereof. The hydrocarbon chain can
have saturated or unsaturated bonds, or substituted or
unsubstituted aromatic and cyclic groups.
[0053] In yet another embodiment, polycarbonate polyols are
included in the polyurethane material of the invention. Suitable
polycarbonates include, but are not limited to, polyphthalate
carbonate and poly(hexamethylene carbonate)glycol. The hydrocarbon
chain can have saturated or unsaturated bonds, or substituted or
unsubstituted aromatic and cyclic groups. In one embodiment, the
molecular weight of the polyol is from about 200 to about 4000.
[0054] Polyamine curatives are also suitable for use in the
polyurethane composition of the invention and have been found to
improve cut, shear, and impact resistance of the resultant balls.
Preferred polyamine curatives include, but are not limited to,
3,5-dimethylthio-2,4-toluenediamine and isomers thereof;
3,5-diethyltoluene-2,4-diamine and isomers thereof, such as
3,5-diethyltoluene-2,6-diamine;
4,4'-bis-(sec-butylamino)-diphenylmethane;
1,4-bis-(sec-butylamino)-benzene,
4,4'-methylene-bis-(2-chloroaniline);
4,4'-methylene-bis-(3-chloro-2,6-diethylaniline);
polytetramethyleneoxide-di-p-aminobenzoate; N,N'-dialkyldiamino
diphenyl methane; p,p'-methylene dianiline; m-phenylenediamine;
4,4'-methylene-bis-(2-chloroaniline); 4,4'
-methylene-bis-(2,6-diethylaniline);
4,4'-methylene-bis-(2,3-dichloroaniline);
4,4'-diamino-3,3'-diethyl-5,5'-dimethyl diphenylmethane; 2,2',
3,3'-tetrachloro diamino diphenylmethane; trimethylene glycol
di-p-aminobenzoate; and mixtures thereof. Preferably, the curing
agent of the present invention includes
3,5-dimethylthio-2,4-toluenediamine and isomers thereof, such as
ETHACURE.RTM. 300, commercially available from Albermarle
Corporation of Baton Rouge, La. Suitable polyamine curatives, which
include both primary and secondary amines, preferably have
molecular weights ranging from about 64 to about 2000.
[0055] At least one of a diol, triol, tetraol, or
hydroxy-terminated curatives may be added to the aforementioned
polyurethane composition. Suitable diol, triol, and tetraol groups
include ethylene glycol; diethylene glycol; polyethylene glycol;
propylene glycol; polypropylene glycol; lower molecular weight
polytetramethylene ether glycol; 1,3-bis(2-hydroxyethoxy)benzene;
1,3-bis42-(2-hydroxyethoxy)ethoxy]benzene;
1,3-bis-{2-[2-(2-hydroxyethoxy)ethoxy]ethoxy}benzene;
1,4-butanediol; 1,5-pentanediol; 1,6-hexanediol;
resorcinol-di-(.beta.-hydroxyethyl)ether;
hydroquinone-di-(.beta.-hydroxyethyl)ether; and mixtures thereof.
Preferred hydroxy-terminated curatives include
1,3-bis(2-hydroxyethoxy)benzene; 1,3-bis-[2-(2-hydroxyethoxy)
ethoxy]benzene;
1,3-bis-{2-[2-(2-hydroxyethoxy)ethoxy]ethoxy}benzene;
1,4-butanediol, and mixtures thereof. Preferably, the
hydroxy-terminated curatives have molecular weights ranging from
about 48 to 2000. It should be understood that molecular weight, as
used herein, is the absolute weight average molecular weight and
would be understood as such by one of ordinary skill in the
art.
[0056] Both the hydroxy-terminated and amine curatives can include
one or more saturated, unsaturated, aromatic, and cyclic groups.
Additionally, the hydroxy-terminated and amine curatives can
include one or more halogen groups. The polyurethane composition
can be formed with a blend or mixture of curing agents. If desired,
however, the polyurethane composition may be formed with a single
curing agent.
[0057] In one embodiment of the present invention, saturated
polyurethanes are used to form one or more of the cover layers.
[0058] Additionally, polyurethane can be replaced with or blended
with a polyurea material. Polyureas are distinctly different from
polyurethane compositions, giving better shear resistance.
[0059] The polyether amine may be blended with additional polyols
to formulate copolymers that are reacted with excess isocyanate to
form the polyurea prepolymer. In one embodiment, less than about 30
percent polyol by weight of the copolymer is blended with the
saturated polyether amine. In another embodiment, less than about
20 percent polyol by weight of the copolymer, preferably less than
about 15 percent by weight of the copolymer, is blended with the
polyether amine. The polyols listed above with respect to the
polyurethane prepolymer, e.g., polyether polyols, polycaprolactone
polyols, polyester polyols, polycarbonate polyols, hydrocarbon
polyols, other polyols, and mixtures thereof, are also suitable for
blending with the polyether amine. The molecular weight of these
polymers may be from about 200 to about 4000, but also may be from
about 1000 to about 3000, and more preferably are from about 1500
to about 2500.
[0060] The polyurea composition can be formed by crosslinking a
polyurea prepolymer with a single curing agent or a blend of curing
agents. In one embodiment, the amine-terminated curing agent may
have a molecular weight of about 64 or greater. In another
embodiment, the molecular weight of the amine-curing agent is about
2000 or less. As discussed above, certain amine-terminated curing
agents may be modified with a compatible amine-terminated freezing
point depressing agent or mixture of compatible freezing point
depressing agents
[0061] Suitable amine-terminated curing agents include, but are not
limited to, ethylene diamine; hexamethylene diamine;
1-methyl-2,6-cyclohexyl diamine; tetrahydroxypropylene ethylene
diamine; 2,2,4- and 2,4,4-trimethyl-1,6-hexanediamine;
4,4'-bis-(sec-butylamino)-dicyclohexylmethane;
1,4-bis-(sec-butylamino)-cyclohexane;
1,2-bis-(sec-butylamino)-cyclohexane; derivatives of
4,4'-bis-(sec-butylamino)-dicyclohexylmethane;
4,4'-dicyclohexylmethane diamine;
1,4-cyclohexane-bis-(methylamine);
1,3-cyclohexane-bis-(methylamine); diethylene glycol
di-(aminopropyl) ether; 2-methylpentamethylene-diamine;
diaminocyclohexane; diethylene triamine; triethylene tetramine;
tetraethylene pentamine; propylene diamine; 1,3-diaminopropane;
dimethylamino propylamine; diethylamino propylamine; dipropylene
triamine; imido-bis-propylamine; monoethanolamine, diethanolamine;
3,5-diethyltoluene-2,4-diamine; triethanolamine;
monoisopropanolamine, diisopropanolamine; isophoronediamine;
4,4'-methylenebis-(2-chloroaniline);
3,5-dimethylthio-2,4-toluenediamine;
3,5-dimethylthio-2,6-toluenediamine;
3,5-diethylthio-2,4-toluenediamine;
3,5-diethylthio-2,6-toluenediamine;
4,4'-bis-(sec-butylamino)-diphenylmethane and derivatives thereof;
1,4-bis-(sec-butylamino)-benzene; 1,2-bis-(sec-butylamino)-benzene;
N,N'-dialkylamino-diphenylmethane;
N,N,N',N'-tetrakis(2-hydroxypropyl)ethylene diamine;
trimethyleneglycol-di-p-aminobenzoate;
polytetramethyleneoxide-di-p-aminobenzoate;
4,4'-methylenebis-(3-chloro-2,6-diethyleneaniline);
4,4'-methylenebis-(2,6-diethylaniline); meta-phenylenediamine;
paraphenylenediamine; and mixtures thereof. In one embodiment, the
amine-terminated curing agent is
4,4'-bis-(sec-butylamino)-dicyclohexylmethane.
[0062] Suitable saturated amine-terminated curing agents include,
but are not limited to, ethylene diamine; hexamethylene diamine;
1-methyl-2,6-cyclohexyl diamine; tetrahydroxypropylene ethylene
diamine; 2,2,4- and 2,4,4-trimethyl-1,6-hexanediamine;
4,4'-bis-(sec-butylamino)-dicyclohexylmethane;
1,4-bis-(sec-butylamino)-cyclohexane;
1,2-bis-(sec-butylamino)-cyclohexane; derivatives of
4,4'-bis-(sec-butylamino)-dicyclohexylmethane; ;
4,4'-dicyclohexylmethane diamine;
4,4'-methylenebis-(2,6-diethylaminocyclohexane;
1,4-cyclohexane-bis-(methylamine);
1,3-cyclohexane-bis-(methylamine); diethylene glycol
di-(aminopropyl)ether; 2-methylpentamethylene-diamine;
diaminocyclohexane; diethylene triamine; triethylene tetramine;
tetraethylene pentamine; propylene diamine; 1,3-diaminopropane;
dimethylamino propylamine; diethylamino propylamine;
imido-bis-propylamine; monoethanolamine, diethanolamine;
triethanolamine; monoisopropanolamine, diisopropanolamine;
isophoronediamine; triisopropanolamine; and mixtures thereof. In
addition, any of the polyether amines listed above may be used as
curing agents to react with the polyurea prepolymers.
[0063] Alternatively, other suitable polymers include partially or
fully neutralized ionomer, metallocene, or other single-site
catalyzed polymer, polyester, polyamide, non-ionomeric
thermoplastic elastomer, copolyether-esters, copolyether-amides,
polycarbonate, polybutadiene, polyisoprene, polystryrene block
copolymers (such as styrene-butadiene-styrene),
styrene-ethylene-propylene-styrene,
styrene-ethylene-butylene-styrene, and the like, and blends
thereof.
[0064] Intermediate layers and/or cover layers may also be formed
from ionomeric polymers or ionomer blends such as Surlyn 7940/8940
or Surlyn 8150/9150 or from highly-neutralized ionomers (HNP).
[0065] In one embodiment, at least one intermediate layer of the
golf ball is formed from an HNP material or a blend of HNP
materials. The acid moieties of the HNP's, typically ethylene-based
ionomers, are preferably neutralized greater than about 70%, more
preferably greater than about 90%, and most preferably at least
about 100% with a cation source. Suitable cation sources include
metal cations and salts thereof , organic amine compounds,
ammonium, and combinations thereof. The HNP's can be also be
blended with a second polymer component, which, if containing an
acid group(s) such as organic acids, or more preferably fatty
acids, may be neutralized in a conventional manner, with a suitable
cation source. The second polymer component, which may be partially
or fully neutralized, preferably comprises ionomeric copolymers and
terpolymers, ionomer precursors, thermoplastics, polyamides,
polycarbonates, polyesters, polyurethanes, polyureas, thermoplastic
elastomers, polybutadiene rubber, balata, metallocene-catalyzed
polymers (grafted and non-grafted), single-site polymers,
high-crystalline acid polymers, cationic ionomers, and the like.
HNP polymers typically have a material hardness of between about 20
and about 80 Shore D, and a flexural modulus of between about 3,000
psi and about 200,000 psi.
[0066] In one embodiment of the present invention the HNP's are
ionomers and/or their acid precursors that are preferably
neutralized, either fully or partially, with sufficient amount of
metal base to achieve the desired neutralization level. The acid
copolymers are preferably .alpha.-olefin, such as ethylene,
C.sub.3-8 .alpha.,.beta.-ethylenically unsaturated carboxylic acid,
such as acrylic and methacrylic acid, copolymers. They may
optionally contain a softening monomer, such as alkyl acrylate and
alkyl methacrylate, wherein the alkyl groups have from 1 to 8
carbon atoms.
[0067] The acid copolymers can be described as E/X/Y copolymers
where E is ethylene, X is an .alpha.,.beta.-ethylenically
unsaturated carboxylic acid, and Y is a softening comonomer. In a
preferred embodiment, X is acrylic or methacrylic acid and Y is a
C.sub.1-8 alkyl acrylate or methacrylate ester. X is preferably
present in an amount from about 1 to about 35 weight percent of the
polymer, more preferably from about 5 to about 30 weight percent of
the polymer, and most preferably from about 10 to about 20 weight
percent of the polymer. Y is preferably present in an amount from
about 0 to about 50 weight percent of the polymer, more preferably
from about 5 to about 25 weight percent of the polymer, and most
preferably from about 10 to about 20 weight percent of the
polymer.
[0068] Specific acid-containing ethylene copolymers include, but
are not limited to, ethylene/acrylic acid/n-butyl acrylate,
ethylene/methacrylic acid/n-butyl acrylate, ethylene/methacrylic
acid/iso-butyl acrylate, ethylene/acrylic acid/iso-butyl acrylate,
ethylene/methacrylic acid/n-butyl methacrylate, ethylene/acrylic
acid/methyl methacrylate, ethylene/acrylic acid/methyl acrylate,
ethylene/methacrylic acid/methyl acrylate, ethylene/methacrylic
acid/methyl methacrylate, and ethylene/acrylic acid/n-butyl
methacrylate. Preferred acid-containing ethylene copolymers
include, ethylene/methacrylic acid/n-butyl acrylate,
ethylene/acrylic acid/n-butyl acrylate, ethylene/methacrylic
acid/methyl acrylate, ethylene/acrylic acid/ethyl acrylate,
ethylene/methacrylic acid/ethyl acrylate, and ethylene/acrylic
acid/methyl acrylate copolymers. The most preferred acid-containing
ethylene copolymers are, ethylene/(meth)acrylic acid/n-butyl,
acrylate, ethylene/(meth)acrylic acid/ethyl acrylate, and
ethylene/(meth)acrylic acid/methyl acrylate copolymers.
[0069] Ionomers are typically neutralized with a metal cation, such
as Li, Na, Mg, K, Ca, or Zn. It has been found that by adding
sufficient organic acid or salt of organic acid, along with a
suitable base, to the acid copolymer or ionomer, the ionomer can be
neutralized, without losing processability, to a level much greater
than for a metal cation alone. Preferably, the acid moieties are
neutralized greater than about 80%, preferably from 90-100%, most
preferably 100% without losing processability. This is accomplished
by melt-blending an ethylene .alpha.,.beta.-ethylenically
unsaturated carboxylic acid copolymer, for example, with an organic
acid or a salt of organic acid, and adding a sufficient amount of a
cation source to increase the level of neutralization of all the
acid moieties (including those in the acid copolymer and in the
organic acid) to greater than 90%, (preferably greater than
100%).
[0070] The organic acids may be aliphatic, mono- or
multi-functional (saturated, unsaturated, or multi-unsaturated)
organic acids. Salts of these organic acids may also be employed.
The salts of organic acids of the present invention include the
salts of barium, lithium, sodium, zinc, bismuth, chromium, cobalt,
copper, potassium, strontium, titanium, tungsten, magnesium,
cesium, iron, nickel, silver, aluminum, tin, or calcium, salts of
fatty acids, particularly stearic, behenic, erucic, oleic, linoelic
or dimerized derivatives thereof. It is preferred that the organic
acids and salts of the present invention be relatively
non-migratory (they do not bloom to the surface of the polymer
under ambient temperatures) and non-volatile (they do not
volatilize at temperatures required for melt-blending).
[0071] The ionomers may also be more conventional ionomers, i.e.,
partially-neutralized with metal cations. The acid moiety in the
acid copolymer is neutralized about 1 to about 90%, preferably at
least about 20 to about 75%, and more preferably at least about 40
to about 70%, to form an ionomer, by a cation such as lithium,
sodium, potassium, magnesium, calcium, barium, lead, tin, zinc,
aluminum, or a mixture thereof.
[0072] The golf ball may also contain additives, ingredients, and
other materials in amounts that do not detract from the properties
of the final composition. These additive materials include, but are
not limited to, activators such as calcium or magnesium oxide;
fatty acids such as stearic acid and salts thereof; fillers and
reinforcing agents such as organic or inorganic particles, for
example, clays, talc, calcium, magnesium carbonate, silica,
aluminum silicates, zeolites, powdered metals, and organic or
inorganic fibers, plasticizers such as dialkyl esters of
dicarboxylic acids; surfactants; softeners; tackifiers; waxes;
ultraviolet (UV) light absorbers and stabilizers; antioxidants;
optical brighteners; whitening agents such as titanium dioxide and
zinc oxide; dyes and pigments; processing aids; release agents; and
wetting agents. These compositions provide improved melt
processability, and a balance of ball performance.
[0073] Blowing/foaming agents may also be compatible with and be
included in golf balls of the invention, including, for example
those disclosed in U.S. Pat. No. 7,708,654. Typical physical
foaming/blowing agents include volatile liquids such as freons
(CFCs), other halogenated hydrocarbons, water, aliphatic
hydrocarbons, gases, and solid blowing agents, i.e., compounds that
liberate gas as a result of desorption of gas. Preferably, the
blowing agent includes an adsorbent. Typical adsorbents include,
for example, activated carbon, calcium carbonate, diatomaceous
earth, and silicates saturated with carbon dioxide.
[0074] Chemical foaming/blowing agents may be incorporated.
Chemical blowing agents may be inorganic, such as ammonium
carbonate and carbonates of alkalai metals, or may be organic, such
as azo and diazo compounds, such as nitrogen-based azo compounds.
Suitable azo compounds include, but are not limited to,
2,2'-azobis(2-cyanobutane), 2,2'-azobis(methylbutyronitrile),
azodicarbonamide, p,p'-oxybis(benzene sulfonyl hydrazide),
p-toluene sulfonyl semicarbazide, p-toluene sulfonyl hydrazide.
Other blowing agents include any of the Celogens.RTM., sold by
Crompton Chemical Corporation, and nitroso compounds,
sulfonylhydrazides, azides of organic acids and their analogs,
triazines, tri- and tetrazole derivatives, sulfonyl semicarbazides,
urea derivatives, guanidine derivatives, and esters such as
alkoxyboroxines. Other possible blowing agents include agents that
liberate gasses as a result of chemical interaction between
components such as mixtures of acids and metals, mixtures of
organic acids and inorganic carbonates, mixtures of nitriles and
ammonium salts, and the hydrolytic decomposition of urea.
[0075] Alternatively, low specific gravity can be achieved by
incorporating low density fillers or agents such as hollow fillers
or microspheres in the polymeric matrix, where the cured
composition has the preferred specific gravity. Moreover, the
polymeric matrix can be foamed to decrease its specific gravity,
microballoons, or other low density fillers as described in U.S.
Pat. No. 6,692,380 ("'380 Patent"). The '380 patent is incorporated
by reference in its entirety.
[0076] Blends including non-ionomeric and olefin-based ionomeric
polymers may also be incorporated to form a golf ball layer.
Examples of non-ionomeric polymers include vinyl resins,
polyolefins including those produced using a single-site catalyst
or a metallocene catalyst, polyurethanes, polyureas, polyamides,
polyphenylenes, polycarbonates, polyesters, polyacrylates,
engineering thermoplastics, and the like. Also, in one embodiment
of the invention, processability of the golf ball of the invention
may even be enhanced by incorporating in the core a
metallocene-catalyzed polybutadiene.
[0077] Olefin-based ionomers, such as ethylene-based copolymers,
normally include an unsaturated carboxylic acid, such as
methacrylic acid, acrylic acid, or maleic acid. Other possible
carboxylic acid groups include, for example, crotonic, maleic,
fumaric, and itaconic acid. "Low acid" and "high acid" olefin-based
ionomers, as well as blends of such ionomers, may be used. In
general, low acid ionomers are considered to be those containing 16
wt. % or less of carboxylic acid, whereas high acid ionomers are
considered to be those containing greater than 16 wt. % of
carboxylic acid. The acidic group in the olefin-based ionic
copolymer is partially or totally neutralized with metal ions such
as zinc, sodium, lithium, magnesium, potassium, calcium, manganese,
nickel, chromium, copper, or a combination thereof. For example,
ionomeric resins having carboxylic acid groups that are neutralized
from about 10 percent to about 100 percent may be used. In one
embodiment, the acid groups are partially neutralized. That is, the
neutralization level is from 10 to 80%, more preferably 20 to 70%,
and most preferably 30 to 50%. In another embodiment, the acid
groups are highly or fully neutralized. Or, the neutralization
level may be from about 80 to 100%, more preferably 90 to 100%, and
most preferably 95 to 100%. The blend may contain about 5 to about
30% by weight of the moisture barrier composition and about 95 to
about 70% by weight of a partially, highly, or fully-neutralized
olefin-based ionomeric copolymer. The above-mentioned blends may
contain one or more suitable compatibilizers such as glycidyl
acrylate or glycidyl methacrylate or maleic anhydride
containing-polymers.
[0078] In one embodiment, the overall golf ball has a compression
of from about 25 to about 110. In another embodiment, the overall
golf ball has a compression of from about 35 to about 100. In yet
another embodiment, the overall golf ball has a compression of from
about 45 to about 95. In still another embodiment, the compression
may be from about 55 to about 85, or from about 65 to about 75.
Meanwhile, the compression may also be from about 50 to about 110,
or from about 60 to about 100, or from about 70 to about 90, or
even from about 80 to about 110.
[0079] Generally, in golf balls of the invention, the overall golf
ball COR is at least about 0.780. In another embodiment, the
overall golf ball COR is at least about 0.788. In yet another
embodiment, the overall golf ball COR is at least about 0.791. In
still another embodiment, the overall golf ball COR is at least
about 0.794. Also, the overall golf ball COR may be at least about
0.797. The overall golf ball COR may even be at least about 0.800,
or at least about 0.803, or at least about 0.812.
[0080] The core, intermediate layer(s) and/or cover layers may
contain sections having the same hardness or different hardness
levels. That is, there can be uniform hardness throughout the
different sections of the core or there can be hardness gradients
across the layers. For example, in single cores, there may be a
hard-to-soft gradient (a "positive" gradient) from the surface of
the core to the geometric center of the core. In other instances,
there may be a soft-to-hard gradient (a "negative" gradient) or
zero hardness gradient from the core's surface to the core's
center. For dual core golf balls, the inner core layer may have a
surface hardness that is less than the geometric center hardness to
define a first "negative" gradient. As discussed above, an outer
core layer may be formed around the inner core layer, and the outer
core layer may have an outer surface hardness less than its inner
surface hardness to define a second "negative" gradient. In other
versions, the hardness gradients from surface to center may be
hard-to-soft ("positive"), or soft-to-hard ("negative"), or a
combination of both gradients. In still other versions the hardness
gradients from surface to center may be "zero" (that is, the
hardness values are substantially the same.) Methods for making
cores having positive, negative, and zero hardness gradients are
known in the art as described in, for example, U.S. Pat. Nos.
7,537,530; 7,537,529; 7,427,242; and 7,410,429, the disclosures of
which are hereby incorporated by reference.
[0081] A golf ball according to the invention may therefore achieve
various hardness gradients therein. For example, a golf ball of the
invention having unique color appearance may incorporate a
single-solid core having a "positive" hardness gradient (that is,
the outer surface of the core is harder than its geometric center.)
In a second embodiment, the core may be a dual-core comprising an
inner core and a surrounding outer core layer. The inner core has a
"positive" hardness gradient and the outer core layer has a
"negative" hardness gradient (that is, the outer surface of the
outer core layer is softer than the inner surface of the outer core
layer.) Other embodiments of golf balls having various combinations
of positive, negative, and zero hardness gradients may be made in
accordance with this invention. For example, the inner core may
have a positive hardness gradient and the outer core layer also may
have a positive hardness gradient. In another example, the inner
core may have a positive hardness gradient and the outer core layer
may have a "zero" hardness gradient. (That is, the hardness values
of the outer surface of the outer core layer and the inner surface
of the outer core layer are substantially the same.) Particularly,
the term, "zero hardness gradient" as used herein, means a surface
to center Shore C hardness gradient of less than 8, preferably less
than 5 and most preferably less than 3 and may have a value of zero
or negative 1 to negative 25. The term, "negative hardness
gradient" as used herein, means a surface to center Shore C
hardness gradient of less than zero. The terms, zero hardness
gradient and negative hardness gradient, may be used herein
interchangeably to refer to hardness gradients of negative 1 to
negative 25. The term, "positive hardness gradient" as used herein,
means a surface to center Shore C hardness gradient of 8 or
greater, preferably 10 or greater, and most preferably 20 or
greater. By the term, "steep positive hardness gradient" as used
herein, it is meant surface to center Shore C hardness gradient of
20 or greater, more preferably 25 or greater, and most preferably
30 or greater. Methods for measuring the hardness of the inner core
and surrounding layers and determining the hardness gradients are
discussed in further detail below.
[0082] The center hardness of a core is obtained according to the
following procedure. The core is gently pressed into a
hemispherical holder having an internal diameter approximately
slightly smaller than the diameter of the core, such that the core
is held in place in the hemispherical portion of the holder while
concurrently leaving the geometric central plane of the core
exposed. The core is secured in the holder by friction, such that
it will not move during the cutting and grinding steps, but the
friction is not so excessive that distortion of the natural shape
of the core would result. The core is secured such that the parting
line of the core is roughly parallel to the top of the holder. The
diameter of the core is measured 90 degrees to this orientation
prior to securing. A measurement is also made from the bottom of
the holder to the top of the core to provide a reference point for
future calculations. A rough cut is made slightly above the exposed
geometric center of the core using a band saw or other appropriate
cutting tool, making sure that the core does not move in the holder
during this step. The remainder of the core, still in the holder,
is secured to the base plate of a surface grinding machine. The
exposed `rough` surface is ground to a smooth, flat surface,
revealing the geometric center of the core, which can be verified
by measuring the height from the bottom of the holder to the
exposed surface of the core, making sure that exactly half of the
original height of the core, as measured above, has been removed to
within 0.004 inches. Leaving the core in the holder, the center of
the core is found with a center square and carefully marked and the
hardness is measured at the center mark according to ASTM D-2240.
Additional hardness measurements at any distance from the center of
the core can then be made by drawing a line radially outward from
the center mark, and measuring the hardness at any given distance
along the line, typically in 2 mm increments from the center. The
hardness at a particular distance from the center should be
measured along at least two, preferably four, radial arms located
180.degree. apart, or 90.degree. apart, respectively, and then
averaged. All hardness measurements performed on a plane passing
through the geometric center are performed while the core is still
in the holder and without having disturbed its orientation, such
that the test surface is constantly parallel to the bottom of the
holder, and thus also parallel to the properly aligned foot of the
durometer.
[0083] The outer surface hardness of a golf ball layer is measured
on the actual outer surface of the layer and is obtained from the
average of a number of measurements taken from opposing
hemispheres, taking care to avoid making measurements on the
parting line of the core or on surface defects, such as holes or
protrusions. Hardness measurements are made pursuant to ASTM D-2240
"Indentation Hardness of Rubber and Plastic by Means of a
Durometer." Because of the curved surface, care must be taken to
ensure that the golf ball or golf ball subassembly is centered
under the durometer indentor before a surface hardness reading is
obtained. A calibrated, digital durometer, capable of reading to
0.1 hardness units may be used for the hardness measurements. The
digital durometer is attached to, and its foot made parallel to,
the base of an automatic stand. The weight on the durometer and
attack rate conform to ASTM D-2240. In certain embodiments, a point
or plurality of points measured along the "positive" or "negative"
gradients may be above or below a line fit through the gradient and
its outermost and innermost hardness values. In an alternative
preferred embodiment, the hardest point along a particular steep
"positive" or "negative" gradient may be higher than the value at
the innermost portion of the inner core (the geometric center) or
outer core layer (the inner surface)--as long as the outermost
point (i.e., the outer surface of the inner core) is greater than
(for "positive") or lower than (for "negative") the innermost point
(i.e., the geometric center of the inner core or the inner surface
of the outer core layer), such that the "positive" and "negative"
gradients remain intact.
[0084] As discussed above, the direction of the hardness gradient
of a golf ball layer is defined by the difference in hardness
measurements taken at the outer and inner surfaces of a particular
layer. The center hardness of an inner core and hardness of the
outer surface of an inner core in a single-core ball or outer core
layer are readily determined according to the test procedures
provided above. The outer surface of the inner core layer (or other
optional intermediate core layers) in a dual-core ball are also
readily determined according to the procedures given herein for
measuring the outer surface hardness of a golf ball layer, if the
measurement is made prior to surrounding the layer with an
additional core layer. Once an additional core layer surrounds a
layer of interest, the hardness of the inner and outer surfaces of
any inner or intermediate layers can be difficult to determine.
Therefore, for purposes of the present invention, when the hardness
of the inner or outer surface of a core layer is needed after the
inner layer has been surrounded with another core layer, the test
procedure described above for measuring a point located 1 mm from
an interface is used.
[0085] Also, it should be understood that there is a fundamental
difference between "material hardness" and "hardness as measured
directly on a golf ball." For purposes of the present invention,
material hardness is measured according to ASTM D2240 and generally
involves measuring the hardness of a flat "slab" or "button" formed
of the material. Surface hardness as measured directly on a golf
ball (or other spherical surface) typically results in a different
hardness value. The difference in "surface hardness" and "material
hardness" values is due to several factors including, but not
limited to, ball construction (that is, core type, number of cores
and/or cover layers, and the like); ball (or sphere) diameter; and
the material composition of adjacent layers, and thickness of the
various layers. It also should be understood that the two
measurement techniques are not linearly related and, therefore, one
hardness value cannot easily be correlated to the other. Shore C
hardness was measured according to the test methods D-2240.
[0086] Several different methods can be used to measure
compression, including Atti compression, Riehle compression,
load/deflection measurements at a variety of fixed loads and
offsets, and effective modulus. See, e.g., Compression by Any Other
Name, Science and Golf IV, Proceedings of the World Scientific
Congress of Golf (Eric Thain ed., Routledge, 2002) ("J. Dalton")
The term compression, as used herein, refers to Atti or PGA
compression and is measured using an Atti compression test device.
A piston compresses a ball against a spring and the piston remains
fixed while deflection of the spring is measured at 1.25 mm (0.05
inches). Where a core has a very low stiffness, the compression
measurement will be zero at 1.25 mm. In order to measure the
compression of a core using an Atti compression tester, the core
must be shimmed to a diameter of 1.680 inches because these testers
are designed to measure objects having that diameter. Atti
compression units can be converted to Riehle (cores), Riehle
(balls), 100 kg deflection, 130-10 kg deflection or effective
modulus using the formulas set forth in J. Dalton. The approximate
relationship that exists between Atti or PGA compression and Riehle
compression can be expressed as: (Atti or PGA
compression)=(160-Riehle Compression). Thus, a Riehle compression
of 100 would be the same as an Atti compression of 60.
[0087] COR, as used herein, is determined by firing a golf ball or
golf ball subassembly (e.g., a golf ball core) from an air cannon
at two given velocities and calculating the COR at a velocity of
125 ft/s. Ball velocity is calculated as a ball approaches
ballistic light screens which are located between the air cannon
and a steel plate at a fixed distance. As the ball travels toward
the steel plate, each light screen is activated, and the time at
each light screen is measured. This provides an incoming transit
time period inversely proportional to the ball's incoming velocity.
The ball impacts the steel plate and rebounds through the light
screens, which again measure the time period required to transit
between the light screens. This provides an outgoing transit time
period inversely proportional to the ball's outgoing velocity. COR
is then calculated as the ratio of the outgoing transit time period
to the incoming transit time period,
COR=V.sub.out/V.sub.in=T.sub.in/T.sub.out. Preferably, a golf ball
according to the present invention has a COR of at least about
0.78, more preferably, at least about 0.80.
[0088] The spin rate of a golf ball also remains an important golf
ball characteristic. High spin rate allows skilled players more
flexibility in stopping the ball on the green if they are able to
control a high spin ball. On the other hand, recreational players
often prefer a low spin ball since they do not have the ability to
intentionally control the ball, and lower spin balls tend to drift
less off the green.
[0089] Golf ball spin is dependent on variables including, for
example, distribution of the density or specific gravity within a
golf ball. For example, when the center has a higher density or
specific gravity than the outer layers, a lower moment of inertia
results which increases spin rate. Alternatively, when the density
or specific gravity is concentrated in the outer regions of the
golf ball, a higher moment of inertia results with a lower spin
rate. The moment of inertia for a golf ball of the invention may be
from about 0.410 oz-in.sup.2 to about 0.470 oz-in.sup.2. The moment
of inertia for a one piece ball that is 1.62 ounces and 1.68 inches
in diameter may be approximately 0.4572 oz-in.sup.2, which is the
baseline moment of inertia value.
[0090] Accordingly, by varying the materials and the density of the
regions of each core or cover layer, different moments of inertia
may be achieved for the golf ball of the present invention. In one
embodiment, the resulting golf ball has a moment of inertia of from
about to 0.440 to about 0.455 oz-in.sup.2. In another embodiment,
the golf balls of the present invention have a moment of inertia of
from about 0.456 oz-in.sup.2 to about 0.470 oz-in.sup.2. In yet
another embodiment, the golf ball has a moment of inertia of from
about 0.450 oz-in.sup.2 to about 0.460 oz-in.sup.2.
[0091] Unless otherwise expressly specified, all of the numerical
ranges, amounts, values and percentages such as those for amounts
of materials, and others in the specification may be read as if
prefaced by the word "about" even though the term "about" may not
expressly appear with the value, amount or range. Accordingly,
unless indicated to the contrary, the numerical parameters set
forth in the specification and attached claims are approximations
that may vary depending upon the desired properties sought to be
obtained by the present invention. At the very least, and not as an
attempt to limit the application of the doctrine of equivalents to
the scope of the claims, each numerical parameter should at least
be construed in light of the number of reported significant digits
and by applying ordinary rounding techniques.
[0092] Notwithstanding that the numerical ranges and parameters
setting forth the broad scope of the invention are approximations,
the numerical values set forth in the specific examples are
reported as precisely as possible. Any numerical value, however,
inherently contains certain errors necessarily resulting from the
standard deviation found in their respective testing measurements.
Furthermore, when numerical ranges of varying scope are set forth
herein, it is contemplated that any combination of these values
inclusive of the recited values may be used.
[0093] While it is apparent that the illustrative embodiments of
the invention disclosed herein fulfill the preferred embodiments of
the present invention, it is appreciated that numerous
modifications and other embodiments may be devised by those skilled
in the art. Examples of such modifications include reasonable
variations of the numerical values and/or materials and/or
components discussed above. Hence, the numerical values stated
above and claimed below specifically include those values and the
values that are approximate to those stated and claimed values.
Therefore, it will be understood that the appended claims are
intended to cover all such modifications and embodiments, which
would come within the spirit and scope of the present
invention.
[0094] The invention described and claimed herein is not to be
limited in scope by the specific embodiments herein disclosed,
since these embodiments are intended as illustrations of several
aspects of the invention. Any equivalent embodiments are intended
to be within the scope of this invention. Indeed, various
modifications of the invention in addition to those shown and
described herein will become apparent to those skilled in the art
from the foregoing description. For example, the compositions of
the present invention may be used in a variety of equipment. Such
modifications are also intended to fall within the scope of the
appended claims.
[0095] While any of the embodiments herein may have any known
dimple number and pattern, a preferred number of dimples is 252 to
456, and more preferably is 300 to 392. The dimples may comprise
any width, depth, and edge angle and patterns which satisfy the
relationships defined between cover layers as disclosed herein. The
parting line configuration of said pattern may be either a straight
line or a staggered wave parting line (SWPL). In one embodiment,
the golf ball has 302, 320, 328, 330, 332, 352 or 392 dimples,
comprises 5 to 7 dimples sizes, and the parting line is a SWPL.
[0096] In any of these embodiments the single-layer core may be
replaced with a two or more layer core wherein at least one core
layer has a negative hardness gradient. Other than in the operating
examples, or unless otherwise expressly specified, all of the
numerical ranges, amounts, values and percentages such as those for
amounts of materials and others in the specification may be read as
if prefaced by the word "about" even though the term "about" may
not expressly appear with the value, amount or range.
[0097] Accordingly, unless indicated to the contrary, the numerical
parameters set forth in the specification and attached claims are
approximations that may vary depending upon the desired properties
sought to be obtained by the present invention. At the very least,
and not as an attempt to limit the application of the doctrine of
equivalents to the scope of the claims, each numerical parameter
should at least be construed in light of the number of reported
significant digits and by applying ordinary rounding
techniques.
* * * * *