U.S. patent application number 10/638929 was filed with the patent office on 2004-04-15 for golf ball with cover made from fast curing polyurethane.
Invention is credited to Bradley, Wayne R., Simonutti, Frank M..
Application Number | 20040072630 10/638929 |
Document ID | / |
Family ID | 32070157 |
Filed Date | 2004-04-15 |
United States Patent
Application |
20040072630 |
Kind Code |
A1 |
Simonutti, Frank M. ; et
al. |
April 15, 2004 |
Golf ball with cover made from fast curing polyurethane
Abstract
A golf ball includes a wound center and a cover made from fast
curing polyurethane. The fast curing polyurethane is a
two-component polyurethane which includes an isocyanate and a
mixture of isocyanate reactive compounds comprising polyether or
polyester polyol, aliphatic or aromatic (di) amines, and chain
extenders, catalysts, internal mold release agent as needed.
Inventors: |
Simonutti, Frank M.;
(Jackson, TN) ; Bradley, Wayne R.; (Dyer,
TN) |
Correspondence
Address: |
John W. Chestnut, Esq.
Greer, Burns & Crain, Ltd.
Suite 2500
300 South Wacker Drive
Chicago
IL
60606
US
|
Family ID: |
32070157 |
Appl. No.: |
10/638929 |
Filed: |
August 11, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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10638929 |
Aug 11, 2003 |
|
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09624703 |
Jul 24, 2000 |
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Current U.S.
Class: |
473/378 |
Current CPC
Class: |
C08G 18/10 20130101;
A63B 37/0031 20130101; A63B 37/0064 20130101; A63B 37/0003
20130101; A63B 37/0075 20130101; C08G 18/10 20130101; C08G 18/6685
20130101 |
Class at
Publication: |
473/378 |
International
Class: |
A63B 037/12 |
Claims
We claim:
1. A golf ball comprising: a center, a layer of elastic windings
surrounding the center, a cover having a Shore D hardness of 50 to
65 and formed from a fast curing two component polyurethane system
which includes: 1. An isocyanate, and 2. One or more isocyanate
reactive components selected from the class consisting of: a.
polyether polyols, b. polyester polyols, c. aliphatic (di)amines,
and d. aromatic (di)amines.
2. The golf ball of claim 1 in which said polyurethane system is a
thermoset polyurethane.
3. The golf ball of claim 1 in which said isocyanate is
diphenylmethane 4,4-diisocyanate.
4. The golf ball of claim 1 in which said isocyanate is isophorone
diisocyanate.
5. The golf ball of claim 1 in which said polyurethane system
includes an aromatic isocyanate, a polyol, an aliphatic amine, an
aromatic diamine, and a catalyst.
6. A golf ball comprising: a center having a diameter of 1 to 1.4
inch, a layer of elastic windings surrounding the center and having
an outer diameter of 1.52 to 1.60 inch, and a cover having a Shore
D hardness of 50 to 65 and formed from a fast curing two component
polyurethane system comprising: 1. An aromatic isocyanate
prepolymer, 2. an isocyanate reactive compound comprising a polyol,
an aliphatic amine, an aromatic diamine, and a catalyst.
7. The golf ball of claim 6 in which said aromatic isocyanate
prepolymer is diphenylmethane diisocyanate prepolymer.
8. The golf ball of claim 7 in which said polyol is propylene
glycol.
9. The golf ball of claim 8 in which said aromatic diamine is
diethyltoluene diamine.
10. The golf ball of claim 6 in which said polyol is propylene
glycol.
11. The golf ball of claim 6 in which said aromatic diamine is
diethyltoluene diamine.
Description
RELATED APPLICATION
[0001] This application is a continuation-in-part of co-pending
application Ser. No. 09/624,703, filed Jul. 24, 2000.
BACKGROUND
[0002] This invention relates to golf balls, and, more
particularly, to a golf ball which includes a cover made from fast
curing polyurethane.
[0003] Balata (trans-polyisoprene) was the primary material used
for golf ball covers until the late 1960's. Balata covered golf
balls were (and are) preferred because of the soft feel and the
control which the better player can impart to the ball. However,
balata covered golf balls are expensive, and difficult to produce.
Balata balls also generally exhibit poor cut resistance, which is
also not beneficial.
[0004] In the late 1960's, ionomers were introduced by DuPont,
under the trade name Surlyn. Ionomers are copolymers of an olefin
(generally ethylene), and an alpha-beta ethylenically unsaturated
carboxylic acid (generally methacrylic acid). Neutralization of a
number of the acid groups is effected with metal ions, currently
chosen from the group of sodium, lithium, zinc and magnesium.
Ionomer covers are more durable than balata, and are currently the
material of choice on most solid core, and many wound core, golf
balls. However, ionomer materials are generally harder than balata,
and do not provide the golfer with the feel and control of a balata
covered golf ball.
[0005] In the mid-1980's, soft ionomers (known as Very Low Modulus
Ionomers or VLMI) were produced by DuPont. These ionomers are
similar in chemical structure to standard ionomers, with the
addition of an acrylate monomer to soften the material. These
materials allowed for the development of softer ionomer covered
golf balls, but did not produce properties similar to balata.
[0006] Other soft thermoplastic materials (such as thermoplastic
polyurethanes, thermoplastic polyester elastomers, polyether block
amide copolymers, etc.) have been used as covers on golf balls,
with limited success. Although these materials have been
successfully used as mantle (inner cover) layers for golf balls,
they generally produce insufficient resilience properties to be
used as covers for premium golf balls. U.S. Pat. Nos. 5,688,191,
5,759,676, 5,810,678 and 5,813,923 all illustrate the use of a
thermoplastic polyurethane material as a mantle material.
Thermoplastic polyurethane materials have also been used in blends
with other materials, such as ionomers. U.S. Pat. No. 4,674,751
describes blends of thermoplastic polyurethanes with ionomers.
[0007] More recently, wound golf balls made using castable
polyurethane have been developed. Balls made using castable
polyurethane covers have many properties comparable to
balata--similar feel (slightly harder) and comparable performance
properties. Balls made using castable polyurethane materials are
available from Titleist (Titleist Professional) and Maxfli (Maxfli
Revolution).
[0008] U.S. Pat. No. 3,979,126 describes a polyurethane cover
comprising a prepolymer and curing agent having at least two amine
groups. U.S. Pat. No. 3,989,568 describes a castable polyurethane
material made with curing agents having different rates of reaction
to allow for polyurethane to cure sufficiently to form half-shells,
but not cure completely. U.S. Pat. No. 4,123,061 also describes a
polyurethane compound that is cured sufficiently to form preform
half-shells, but not cured to completion until molding of half
shells around a wound core. U.S. Pat. No. 5,334,673 describes a
castable polyurethane golf ball formed using a slow reacting
polyamine curing agent. However, the polyurethane covered golf
balls described in this patent are made using a casting process
which is both difficult and time-consuming. U.S. Pat. Nos.
5,006,297, 5,733,428, 5,888,437 and 5,947,843 all describe various
methods for molding slow curing polyurethane covered golf
balls.
SUMMARY OF THE INVENTION
[0009] The invention provides a golf ball with a cover made using a
fast-curing thermoset polyurethane material produced from the
reaction of two components: 1. an isocyanate, and 2. a mixture of
isocyanate reactive compounds. The resulting golf ball yields
comparable performance properties (feel, resilience, spin rate) to
golf balls made using balata or castable polyurethane covers. The
golf ball can be produced in a closed injection mold (Reaction
Injection Molding) process, which is significantly less
time-consuming, and more economical than standard castable
polyurethane process of the prior art.
DESCRIPTION OF THE DRAWING
[0010] FIG. 1 is a sectional view of a three-piece wound golf ball
with a cover which is formed in accordance with the invention.
DESCRIPTION OF SPECIFIC EMBODIMENTS
[0011] Referring to FIG. 1, a three-piece golf ball 10 includes a
center 11, a layer of elastic windings 12, and a cover 13. The
center can be solid or liquid filled and has a diameter within the
range of 1 to 1.4 inches, more preferably 1.0 to 1.25 inches. The
windings can be formed, for example, from isoprene or natural
rubber thread. The outer diameter of the layer of windings is
within the range of 1.52 to 1.60 inches, more preferably 1.56 to
1.58 inches. According to the rules of the United States Golf
Association, the outer diameter of the cover must be at least 1.680
inches.
[0012] The cover 13 is formed from a fast curing two-component
polyurethane system comprising:
[0013] 1. an isocyanate;
[0014] 2. a mixture of isocyanate reactive compounds comprising one
or more of:
[0015] a. a polyether or polyester polyol;
[0016] b. aliphatic or aromatic amines or diamines;
[0017] c. chain extenders or crossliners;
[0018] d. catalysts;
[0019] e. internal mold release agents;
[0020] f. colorants fillers, and other standard cover
ingredients.
[0021] The polyurethane cover has a Shore D hardness of 50 to
65.
[0022] Isocyanates suitable for use in this compound include (but
are not limited to) diphenylmethane-4,4'-diisocyanate (MDI) or an
aliphatic isocyanate such as isophorone diisocyanate.
[0023] Polyether polyols suitable for use in the isocyanate
reactive compound include (but are not limited to) propylene
glycol, glycerine and trimethylolpropane.
[0024] Polyester polyols suitable for use in the isocyanate
reactive compound include (but are not limited to) ethylene glycol,
diethylene glycol, and butanediol.
[0025] Chain extenders, catalysts, internal mold releases,
colorants, etc. are used as needed.
[0026] A preferred construction for the golf ball is:
[0027] 1. a solid or liquid-filled center having diameter of
1.0-1.25 inches;
[0028] 2. a center wound with isoprene or natural rubber thread to
an outside diameter of about 1.56 to 1.58 inches;
[0029] 3. a cover formed from a fast-curing polyurethane comprising
two components;
[0030] a. an aromatic isocyanate prepolymer (Diphenylmethane
Diisocyanate prepolymer) and
[0031] b. an isocyanate reactive compound, consisting of a polyol
(propylene glycol), an aliphatic amine, an aromatic diamine
(diethyltoluene diamine), and a catalyst (an organotin
compound).
[0032] Polyurethane materials suitable for use as the cover are
commercially available from Bayer Corporation, under the trade name
Bayer.
[0033] Table 1 lists the properties of polyurethane materials from
Bayflex Corporation which are suitable for use in the
invention.
1TABLE 1 Specific Shore Flex. Mix Ratio Material Grade Gravity D
Modulus Comp. A Comp. B Bayflex 110-25 1.04 50 25,000 psi 47.5 100
Bayflex 110-35 1.00 55 35,000 psi 52.9 100 Bayflex 110-50 1.04 58
52,000 psi 58 100 Note: Test values of polyurethane materials taken
from Bayer Corporation product specifications. Component A:
Aromatic isocyanate prepolymer (Diphenylmethane diisocyanate
prepolymer) Component B: Polyether Polyol System containing an
Aliphatic amine and an Aromatic diamine.
[0034] Golf balls were prepared in accordance with Table 2. The
physical properties of the golf balls are also listed in Table
2.
2TABLE 2 Com- Shore C.O.R. Ball Center pression D 125 f/s 150 f/s
175 f/s I.V. Example 1 Liquid 88 52 0.766 0.745 253.4 Examp1e 2
Solid 92 60 0.769 0.745 253.8 Titleist Liquid 96.7 57 0.786 0.772
254.8 Professional Example 3 Solid 104.9 54 0.793 0.774 0.749 255.7
Maxfli Solid 88.9 57 0.790 0.768 0.743 256.5 Revolution
Compression--Measured using Atti Compression machine. Shore D
Hardness --Measured according to ASTM D-2240 except measured on a
round golf ball. C.O.R. (125 ft/s)--Ratio of Outbound/Inbound
velocity--125 ft/s inbound velocity test setup. C.O.R. (150
ft/s)--Ratio of Outbound/Inboard velocity--150 ft/s inbound
velocity test setup. C.O.R. (175 ft/s)--Ratio of Outbound/Inbound
velocity--175 ft/s inbound velocity test setup. I.V.--initial
velocity measured in accordance with the U.S.G.A. test
[0035] The ball of Example 1 was made using a liquid filled center
(produced by Abbott Laboratories, and wound with Fulflex thread to
a diameter of 1.57 inches. The cover was reaction injection molded
from Bayflex 110-25 polyurethane.
[0036] The ball of Example 2 was made using a solid center, and
wound to a diameter of about 1.57 inches. The cover was reaction
injection molded from Bayflex 110-50.
[0037] The ball of Example 3 was made using a solid center, and
wound to a diameter of about 1.58 inches. The cover was reaction
injection molded from Bayflex 110-35.
[0038] The covers of all of the golf balls of the Examples were
injection molded over the core using a Hennecke 55 Reaction
Injection Molding press and a single cavity mold. The Bayflex cover
material was mixed at a ratio consistent with the ratios described
in Table 1, with the following injection conditions:
[0039] 1. Throughput of about 35 g/s.
[0040] 2. Injection time set at 0.8 seconds.
[0041] 3. Mold temperature of 150.degree. F.
[0042] 4. Isocyanate prepolymer pressure of about 2500 psi.
[0043] 5. Polyether Polyol system pressure of about 2000 psi.
[0044] The Bayflex grades used for these covers cure to sufficient
hardness to allow demolding in about 10 seconds. The balls were
actually removed form the mold (in fully cured state) after about
30 seconds.
[0045] The ball of Example 1 was molded using Bayflex 110-25 fast
curing polyurethane system, tested for physical properties, and
compared to Titleist Professional (a competitive golf ball made
using a slow curing, castable polyurethane cover). Results indicate
that the balls of Example 1 yield comparable ball compression,
slightly softer cover, and slightly lower resilience
properties.
[0046] The ball of Example 2 was molded using Bayflex 110-50 fast
curing polyurethane system, tested for physical properties, and
also compared to the Titleist Professional ball. The Bayflex 110-50
cover resulted in a slightly higher Shore D hardness than the
Titleist Professional, and comparable compression and slightly
lower resilience properties. The resilience properties of Example
balls 1 and 2, although slightly lower than the Titleist
Professional, are still sufficient for a premium level golf
ball.
[0047] The ball of Example 3 was molded using Bayflex 110-35 fast
curing polyurethane system, tested for physical properties, and
compared to Maxfli Revolution (also a competitive golf ball made
using a slow curing, castable polyurethane cover). The ball of
Example 3 yielded slightly lower cover hardness (Shore D) and
higher ball PGA compression than the Maxfli Revolution. The ball of
Example 3 also yielded comparable resilience properties
(Coefficient of Restitution, Initial Velocity) to the Maxfli
Revolution.
[0048] Overall, the balls of Examples, 1, 2 and 3 illustrate that a
ball with the properties (cover hardness, PGA compression and
resilience properties) required for a premium golf ball can be made
using a fast curing polyurethane cover material. The making of a
polyurethane cover ball using the cover described herein also
allows for a much faster, easier, and less expensive method of
processing than is necessary if using a slow curing, castable
polyurethane cover.
[0049] Curing agents which are suitable for the fast curing
polyurethane system are unhindered aromatic or aliphatic
(di)amines. More specifically, the system includes an aromatic
isocyanate and unhindered aromatic (di)amines. Diethyltoluene
diamine should be considered an unhindered diamine.
[0050] The polyurethane cover is preferably reaction injected
molded around the wound center by placing the wound center in a
two-part mold, closing the mold, mixing the two components of the
polyurethane, and injecting the mixed components into the closed
mold. The details of the reaction injection molding apparatus and
method are described in co-pending United States patent application
entitled "Reaction Injection Molded Golf Ball", Serial No.
09/176,445, filed Oct. 21, 1998, which is incorporated herein by
reference.
[0051] While in the foregoing specification a detailed description
of a specific embodiment of the invention was set forth for the
purpose of illustration, it will be understood that many of the
details hereingiven may be varied considerably by those skilled in
the art without departing from the spirit and scope of the
invention.
* * * * *