# Patent

## Title
Aminoalkyllithium compounds containing cyclic amines and polymers

## Abstract

A golf ball has a core which includes a titanate coupling agent. The core comprises rubber and about 0.2 to 5.0 phr of titanate coupling agent. The titanate coupling agent may be selected from the class consisting of monoalkoxy titanates and neoalkoxy titanates.

## Background
This invention relates to golf balls, and, more particularly, to a golf ball core which includes a titanate coupling.

Golf balls generally fall into three categories: elastic thread, and a cover. The core may include a liquid center and a solid outer layer or mantle which surrounds the center.

Golf ball covers consist primarily of cut-resistant covers and covers which are made from natural or synthetic balata. Cut-resistant covers generally include one or more ionic copolymers or ionomers. Popular ionomers for golf ball covers are available from E.I. DuPont de Nemours & Co. under the trademark Surlyn and from Exxon Corp. under the trademark Iotek.

Golf ball cores generally include natural or synthetic rubber, active ingredients, and inert fillers. The rubber is conventionally polybutadiene. The active ingredients may include a crosslinking agent, a polymerization initiator, and an antioxidant. In a conventional core there is no physical bond between the inert fillers.

The invention utilizes a titanate coupling agent to create a bond between the organic and inorganic phases of the rubber compound. The coupling agent creates a more efficient cured compound, which exhibits higher initial velocity and coefficient of restitution, as well as slightly higher compression and impact durability.

The invention will be explained in conjunction with an illustrative embodiments shown in the accompanying drawing, in which

FIG. 1 is a cross sectional illustration of a solid golf ball formed in accordance with the invention;

FIG. 2 is a cross sectional view of a two-piece golf ball formed in accordance with the invention;

FIG. 3 is a cross sectional view of a three-piece golf ball formed in accordance with the invention; and

FIG. 4 compares coefficient of restitution of cores with and without titanate coupling agents.

FIG. 1 illustrates a solid golf ball 10 having a relatively uniform and homogenous core 11. The outside surface of the core is provided with conventional dimples 12.

FIG. 2 illustrates a two-piece golf ball 13 having a solid core 14 and a cover 15.

FIG. 3 illustrates a three-piece golf ball 16 having a solid core 17, a layer of elastic windings 18, and a cover 19.

The covers 15 and 19 can be formed from natural or synthetic balata, ionomers or other conventional polymers. The cover can be injection molded over the core or windings or can be formed from two hemispherical half shells which are compression molded over the core or windings.

The cores 11, 14, and 17 are formed from a compound comprising: rubber) of a crosslinking agent;

The rubber is preferably polybutadiene, more preferably polybutadiene having a cis-1,4 content of at least 97%.

The crosslinking agent is preferably an acrylate of a zinc salt, for example, zinc diacrylate.

The crosslinking initiator is preferably organic pexoide, more preferably dicumyl peroxide.

The fillers, activators, and antioxidants, and the amounts thereof, can be those which are conventionally used in golf ball cores, for example, zinc oxide and barytes.

The titanate coupling agents are preferably selected from the class consisting of monoalkoxy and neoalkoxy titanates. Suitable coupling agents include: dimethacryl isiostearoyl titanate, isopropyl tri(dodecyl)benzenesulfonyl titanate, etc. neopentyl(diallyl)oxy, tri(dodecyl)benzene-sulfonyl titanate, neopentyl(diallyl)oxy, tri(dioctyl)phosphato titanate, etc.

Table 1 lists the formulas for one control core without a titanate coupling agent and five cores with a titanate coupling agent identified as EX-1 through EX-5.

Cores EX1 through EX-3 include a monoalkoxy titanate coupling agent (KR TTS). Cores EX-4 and EX-5 include a neoalkoxy titanate coupling agent (LICA L12/E). ______________________________________ Titanate Core Blends Material   Cont   EX-1    EX-2  EX-3  EX-4 EX-5 ______________________________________ BR 1207    100    100     100   100   100  100 SR 416D    32     32      32    32    32   32 Zinc Oxide 5      5       5     5     5    5 Barytes    16.2   16.2    16.2  16.2  1.6.2 16.2 Dicup 40C  3      3       3     3     3    3 Wingstay L-HLS 0.2    0.2     0.2   0.2   0.2  0.2 KR TTS     --     0.1     0.25  0.4   --   -- LICA L12/E --     --      --    --    1.25 5 ______________________________________ BR 1207  Goodyear Polybutadiene (97% ciscontent) SR 416D  Sartomer Zinc Diacrylate DiCup 40C  Herculus DiCumyl Peroxide  40% active peroxide content Wingstay LHLS  Goodyear Antioxidant KR TTS  Ken React Titanate Coupling Agent. (Isopropyl triisostearoyl titanate) LICA L12/E  Ken React Titanate Coupling Agent (neopentyl (diallyl) oxy, tri)dioctyl) phosphato titanate). 20% active coupling agent in EVA (Ethylene vinylacetate) carrier.

Table 2 illustrates core properties of the core blends of Table 1. In particular, an improved C.O.R. (coefficient of restitution) is observed compared to the control core by all titanate coupling agent blends. Blends EX-1-EX-3 illustrate increased C.O.R. (and slightly higher compression) when using 0.1-0.4 phr of a monoalkoxy titanate coupling agent. Blends EX-4-EX-5 illustrate increased C.O.R. (and slightly higher compression) when using 0.25-1.0 phr of a neoalkoxy titanate coupling agent.

Blends EX-4 and EX-5 were evaluated using an encapsulated coupling agent. The encapsulated coupling agent is 20% active titanate coupling agent. The level of neoalkoxy titanate coupling agent listed in Table 1 is the level of active coupling agent. ______________________________________ Titanate Core Blends - Physical Properties PGA             C.O.R. Core Blend Size    Comp.    Weight 125 ft/s 150 ft/s ______________________________________ Cont     1.5046" 77       34.32 g 0.781  0.754 EX-1     1.5041" 80.7     34.49 g 0.788  0.757 EX-2     1.5038" 81.3     34.42 g 9.788  0.757 EX-3     1.5061" 81       34.41 g 0.787  0.758 EX-4     1.5038" 82.1     34.52 g 0.789  0.759 EX-5     1.5042" 82.1     34.43 g 0.787  0.757 ______________________________________

FIG. 4 further illustrates the increased C.O.R. properties observed in all cores containing titanate coupling agents. This increase is consistent at inbound test velocities of 125 ft/s and 150 ft/s. A consistent increase of about 0.005 to 0.007 in C.O.R. is observed.

C.O.R. is measured by propelling the core against a hard surface at a specific inbound velocity and measuring the outbound velocity. The ratio of outbound and inbound velocities is the C.O.R.

While in the foregoing specification a detailed description of specific embodiments of the invention were set forth for the purpose of illustration, it will be understood that many of the details herein given can be varied considerably by those skilled in the art without departing from the spirit and scope of the invention.

## Claims

1. A golf ball core comprising:

2. The core of claim 1 including a filler.

3. The core of claim 1 including an activator.

4. The core of claim 1 including an antioxidant.

5. The core of claim 1 in which the titanate coupling agent is selected from the class consisting of monoalkoxy titanates and neoalkoxy titanates.

6. The core of claim 1 in which the core has a coefficient of restitution at 125 feet/second of greater than 0.781.

7. The core of claim 1 in which the core has a coefficient of restitution at 125 feet/second of at least 0.787.

8. The core of claim 1 in which the crosslinking initiator is an organic peroxide.

9. The core of claim 8 in which the organic peroxide is dicumyl peroxide.

10. The core of claim 1 in which the rubber is polybutadiene having a cis-1,4 content of 97%.

11. A golf ball comprising a core and a cover, the core comprising:

12. The golf ball of claim 11 including a layer of elastic windings between the core and the core.

13. The golf ball of claim 11 in which the titanate coupling agent is selected from the class consisting of monoalkoxy titanates and neoalkoxy titanates.

14. The core of claim 11 in which the core has a coefficient of restitution at 125 feet/second of greater than 0.781.

15. The core of claim 11 in which the core has a coefficient of restitution at 125 feet/second of at least 0.787.