JPS60210271A - Golf ball - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a golf pole, and more particularly to a golf pole having an improved liquid core.

[Prior Art] A conventional golf pole with a liquid core generally includes a liquid core, a rubber bag surrounding the liquid core, a thread rubber layer tightly wound thereon, and a cover layer on the outer surface. Here, high pressure is applied to the liquid core due to the winding pressure of the rubber thread, so if the golf pole is cut with a knife, etc., the liquid in the liquid core may scatter due to this high pressure. , there was a risk of eye damage.

Therefore, solid rubber-like cores are being adopted in place of liquid cores, but the hitting feel and other feels are not satisfactory, and there is a strong desire for a golf pole with a liquid core.

[Object of the Invention] The present invention has been made in view of the above-mentioned circumstances, and its purpose is to provide a thread-wound golf pole having a liquid core in which the liquid of the liquid core does not scatter even when cut. There is a particular thing.

[Configuration of the Invention] To achieve this object, the golf pole of the present invention comprises:
It has a liquid core made of a liquid and a crosslinked product of at least one carboxyl group-containing polymer selected from the group consisting of a mixture of a highly water-absorbing substance and a (meth)acrylic acid polymer. A golf pole characterized by the following.

The present invention will be explained in detail below.

The carboxyl group-containing polymer used in the present invention is selected from the group consisting of copolymers of unsaturated compounds and maleic anhydride and (meth)acrylic acid polymers.

The copolymer of an unsaturated compound and maleic anhydride may be a random copolymer, a block copolymer, or an alternating copolymer.

In the present invention, the unsaturated compound refers to an olefin or a vinyl compound, and among these, the olefin has 2 to 2 carbon atoms.
12, preferably 2 to 8 linear or branched unsaturated hydrocarbons, specifically ethylene, propylene,
1-butene, 2-butene, imbutylene, n-pentene, isoprene, 2-methyl-1-butene, n-hexene, 2-methyl-1-pentene, 3-methyl-1-pentene, 4-methyl-1 -Pentene, 2-ethyl-1-butene, n-heptene, n-octene, 5-methyl-2-hexene, diisobutylene, 1.3-butadiene, 1.3
-pentadiene, 1,3-hexadiene, 1,3-octadiene, 2-methyl-4-dimethyl-1-pentene,
2-methyl-4-dimethyl-2-pentene is mentioned. Here, inbutylene also means return BB containing inbutylene.

Vinyl compounds include unsaturated compounds copolymerizable with maleic anhydride, specifically styrene, divinylbenzene, vinyl chloride, vinyl acetate, vinyl propionate, acrylonitrile, methacrylonitrile, methyl vinyl ether, acrylic esters, Examples include vinyl alcohol.

These compounds may be used alone or in combination of two or more. Among these olefin compounds, α-olefins such as ethylene and imbutylene, styrene, or methyl vinyl ether are preferably used, and α-olefins, particularly imbutylene, are most suitable.

α- in maleic anhydride-unsaturated compound copolymer
The composition ratio of the olefin or vinyl compound and maleic anhydride may be at any level as long as the resulting copolymer is soluble in water. When ethylene, imbutylene, styrene, or methyl vinyl ether is used as the unsaturated compound, the composition ratio is about 1 to 3 moles, especially about 1 mole, of ethylene, imbutylene, styrene, or methyl vinyl ether to 1 mole of maleic anhydride. It is preferable that

Such a maleic anhydride-unsaturated compound copolymer is
One type or a combination of two or more types can be used. The molecular weight of these copolymers is such that the intrinsic viscosity (η) measured in dimethylformamide solution at 30°C is 0.1 to
B (d/g), particularly those corresponding to 0.2 to 5 (dfL/g) are preferred. When the intrinsic viscosity is lower than Oll, the crosslinking rate becomes extremely slow, making it difficult to obtain a crosslinked product with a high water absorption capacity. On the other hand, if the intrinsic viscosity is greater than 8, the viscosity of the solution will be high, causing problems in workability and production.

In addition, (meth)acrylic acid polymer, that is, polyacrylic acid or polymethacrylic acid, refers to a polymer obtained by polymerizing acrylic acid or methacrylic acid in a solvent such as water or an organic solvent. ) Acrylic acid esters 1. It also includes those obtained by hydrolyzing poly(meth)acrylonitrile, poly(meth)acrylamide, etc. In addition, a small amount of a vinyl compound that can be copolymerized with polyacrylic acid may be copolymerized with the particles.

The molecular weight of these (meth)acrylic acid-based polymers is such that the intrinsic viscosity (η) measured at 30°C in an aqueous solution containing an electrolyte is 0.
．． 1-10 (d sentence/g), especially 0.5-8 (dJ1/g)
Those corresponding to g) are preferred.

Among these carboxyl group-containing polymers, inbutylene-maleic anhydride is preferred because the viscosity of the reaction solution is low, it is possible to react at high concentrations, and the resulting water-absorbing crosslinked product has excellent durability. Polymers are most preferred.

The method for obtaining a highly water-absorbing crosslinked product from such a carboxyl group-containing polymer is not particularly limited, but for example, the following method is suitable.

First, a carboxyl group-containing polymer is reacted with an alkali metal hydroxide to obtain an alkali metal neutralized product of the carboxyl group-containing polymer.

As the alkali metal hydroxide used, sodium hydroxide, potassium hydroxide, lithium hydroxide, etc. are suitable, and these react with the carboxylic acid or acid anhydride of the carboxyl group-containing polymer to form a carboxyl group-containing polymer. This makes the combination water-soluble, or imparts a hydrophilic group even if it is not completely soluble in water. Two or more of these alkali metal hydroxides may be reacted in combination, and a small amount of ammonia may be used in combination to promote solubility or to enhance the crosslinking reaction.

Next, the alkali metal neutralized product of the carboxyl group-containing polymer is crosslinked using a crosslinking agent. Certain polyvalent amines are effectively used as crosslinking agents. Polyvalent amines that exhibit unique effects as crosslinking agents are water-soluble polyvalent amines that have two or more amino groups in their molecules, and specifically include ethylenediamine, diethylenetriamine, triethylenetetramine, and tetraethylene. Examples include pentamine, pentaethylenehexamine, and linear or branched polyethyleneimine. The molecular weight is preferably about 60 to 5,000 from the viewpoint of the performance of the water-absorbing crosslinked product obtained.

A typical treatment for a crosslinking reaction between an alkali metal neutralized product of a carboxyl group-containing polymer and a polyvalent amine involves dissolving the alkali metal neutralized product in a solvent such as water or alcohol, preferably water; A method is to add a predetermined amount of polyvalent amine necessary to give the final water-absorbing crosslinked product the desired water absorption capacity to the solution, mix and stir thoroughly until it is uniformly dissolved, and then dry and heat-treat. Can be mentioned.

At this time, the carboxyl group-containing polymer may be directly reacted with a polyvalent amine to effect crosslinking.

The water-absorbing crosslinked product obtained in this manner has a water absorption capacity of 20 to 800 times its own weight with respect to distilled water, exhibiting a high water absorption capacity, and exhibiting a high water absorption rate.

Although the form of the crosslinked product is not particularly limited, a powder form is generally preferably used.

The crosslinked product of maleic anhydride-isobutylene copolymer contains
A cured product obtained by using polyvalent amine (polyethyleneimine) as a crosslinking agent in isopane (manufactured by Talalay Isoprene Chemical Co., Ltd., trade name, maleic anhydride: isobutylene = 1:1 (mole ratio)) and KI gel (Kuraray (manufactured by Isoprene Chemical Co., Ltd., trade name) are commercially available and are suitable for use.

The liquid core of the golf pole of the present invention is composed of the water-absorbing crosslinked material and a liquid. Water is preferably used as the liquid, and the crosslinked product of wood and carboxyl group-containing polymer constituting the liquid core contains 75 to 99.9% by weight of water, preferably 96 to 99.9% by weight.
It is preferable to mix in a range of 99.6% by weight.

The method for producing the liquid core is not particularly limited, but preferable methods include a freezing method and a method in which a crosslinked product of a carboxyl group-containing polymer is first placed in a rubber bag and then water is poured into the bag.

(Effects of the Invention) As detailed above, in the golf pole of the present invention, the liquid core is composed of a highly water-absorbing crosslinked material and a liquid, and the liquid in the liquid core has a high viscosity. Even if the pole is cut, the liquid in the liquid core will not scatter, making it extremely safe.Furthermore, the feel, feel, and launch speed characteristic of conventional liquid-core golf balls will not be impaired. do not have.

Therefore, according to the present invention, it is possible to provide a golf pole that is extremely safe and has a good feel.

Agent: Patent attorney Tsuyoshi Shigeno

Claims (1)

[Claims] (1) A liquid core made of a liquid and a crosslinked product of at least one carboxyl group-containing polymer selected from the group consisting of a copolymer of an unsaturated compound and maleic anhydride and a (meth)acrylic acid polymer. A golf pole having: