JP2619913B2 - Surface panel for ball balls - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a surface panel for a ball for ball games.

<Prior Art> At present, three types of natural leather, artificial leather and rubber are known as materials for the outermost surface panel of ball for ball games. As natural leather, leather such as cows is used. For artificial leather, for example, polyester staple fibers are stacked vertically and horizontally one after another and lightly pressed, and then three-dimensionally entangled by needle punching to impregnate a nonwoven fabric with a binder made of a polymer elastomer to form a base.
A surface panel is formed on the substrate by coating or roll transfer. As the rubber, for example, natural and synthetic rubbers are used.

<Problems to be Solved by the Invention> Natural leather has a problem that it wears out in a few months after private use and becomes hard and heavy due to the absorption of rainwater. Further, there is a problem that the size, shape, density, and the like of pores vary depending on the part of the leather and that wrinkles are present, so that uniform quality products are difficult to obtain.

Since artificial leather has an extremely thin surface layer of about 0.01 to 0.03 mm, it has a problem of poor abrasion resistance and poor scratch resistance. The printing applied to this artificial leather is also inferior in abrasion resistance, the surface layer disappears after about 6 months of use, the non-woven fabric layer is exposed, it becomes a felt-like surface, letters and patterns disappear,
The determination becomes extremely difficult. Further, since the nonwoven fabric layer has water absorbability, there is a problem that the nonwoven fabric layer absorbs moisture and becomes heavy.

Rubber skin has a problem that it has an extremely large coefficient of wear, is inferior to natural leather and artificial leather in color, glossiness, rebound resilience, and the like, and has poor weather resistance and thus cracks.

In manufacturing a ball surface panel using natural leather or artificial leather, first, a raw leather fabric is cut into a predetermined panel shape, for example, a soccer ball having a hexagonal shape and a pentagonal shape. The cut leather panel is then subjected to a slender thinning process of the peripheral portion of the panel, called edge cutting. This edge shaving processing is to cut off the leather non-woven fabric layer in an oblique direction, thereby forming a groove in an adjacent portion of the leather panel. However, when such edge processing is performed using such leather, only a groove having a gentle slope is obtained, and there is a problem that a three-dimensional effect as seen in a sewing ball cannot be expressed. Furthermore, in the above-mentioned natural leather and artificial leather,
After the edge cutting process, a process of printing predetermined characters, symbols, patterns, and the like on the surface by hot stamping, silk printing, pad printing, or the like is required. As described above, when a ball skin is manufactured using natural leather and artificial leather, it is necessary to go through a number of steps.

The present invention has been made to solve the above-described problems, and has luster, slipperiness, softness, and rebound resilience similar to natural leather and artificial leather, and is inferior to natural leather and artificial leather in abrasion resistance and resistance. An object of the present invention is to provide a ball surface panel having scratch resistance, water absorption resistance, and higher printing strength.

In addition, the present invention eliminates a series of steps such as cutting, edge cutting, and printing found in conventional natural leather and artificial leather by molding the ball surface panel using an injection molding method. This greatly simplifies manufacturing.

<Means for Solving the Problems> The present invention provides a spherical hollow rubber tube filled with compressed air and a carcass comprising a reinforcing layer formed on the surface of the tube or a thermoplastic elastomer having a reinforcing function. In a surface panel which is bonded to a carcass formed on a body directly or via a thin rubber layer to form a skin of a ball for ball games, the surface panel is obtained by injecting a thermoplastic elastomer material into an injection mold. And has a slanted thin portion on the periphery thereof and a large number of projections on the back surface thereof.

<Embodiment> An example in which the present invention is applied to a soccer ball 1 will be described below. In FIGS. 1 and 2, reference numeral 2 denotes a tube formed by molding butyl rubber or the like into a spherical hollow body, and compressed air is injected through a valve (not shown). 3 is
A reinforcing layer formed by winding a nylon thread of several thousand meters on an endless track on the surface of the tube 2, and maintaining the shape of the ball,
It provides properties such as durability and dimensional stability, and acts to suppress rebound resilience. The tube 2 and the reinforcing layer 3 form a carcass. This tube 2
And the reinforcing layer 3 can be replaced with a thermoplastic elastomer having a reinforcing function, for example, Hytrel (registered trademark),
According to this, a carcass is constituted by a spherical hollow body made of a thermoplastic elastomer. 4 is a thin rubber layer made of natural rubber, synthetic rubber or the like formed on the reinforcing layer 3, and 5 is
A hexagonal and pentagonal surface panels 7, 7,... Are arranged on the rubber thin layer 4 with a skin layer bonded and formed through an adhesive layer 6 made of a vulcanized rubber primer and urethane paste. Things. The rubber thin layer 4 is for improving the adhesive strength of the front panels 7, 7,..., But is not always necessary, and can be omitted and the front panels 7, 7,. it can. The front panels 7, 7,... Are molded by injecting a thermoplastic elastomer material having a hardness (JIS) of about 50 to 90 into an injection mold. Here, examples of the thermoplastic elastomer material include SBS thermoplastics such as Elastomer AE (manufactured by Toa Gosei Chemical Industry Co., Ltd.), Tufprene (registered trademark, manufactured by Asahi Kasei Corporation), and Solprene T (registered trademark, manufactured by Nippon Elastomer Co., Ltd.) Elastomer, Mirastomer (registered trademark, manufactured by Mitsui Petrochemical Industries, Ltd.),
Olefin-based thermoplastic elastomers such as Sumitomo TPE (manufactured by Sumitomo Chemical Co., Ltd.), Sumiflex (registered trademark, manufactured by Sumitomo Bakelite Co., Ltd.), Sunplane (registered trademark, manufactured by Mitsubishi Kasei Vinyl Co., Ltd.), Dencaleomer G (registered trademark, PVC-based thermoplastic elastomers such as Electrochemical Co., Ltd., EZ-800 (Shin-Etsu Polymer Co., Ltd.), Paraprene (registered trademark, Nippon Polyurethane Co., Ltd.), Elastollan (registered trademark, Nippon Elastollan Co., Ltd.) , Pandex (registered trademark, manufactured by Dainippon Ink and Chemicals, Inc.) and other polyester-based thermoplastic elastomers; Perprene (registered trademark, manufactured by Toyobo Co., Ltd.); and Hytrel (registered trademark, manufactured by DuPont); Can be used.

The thermoplastic elastomer is composed of a soft segment and a hard segment having a physical cross-linking action, and has a glass transition temperature lower than room temperature. Therefore, in the operating temperature range of the ball (about -20 ° C to 50 ° C), the surface of the ball is hardened. Has elasticity (about 50 to 90 in JIS hardness) suitable for panels. Unlike the chemical bond such as vulcanization in rubber, the physical crosslink melts at a high temperature, and can be formed into a desired shape by injection molding.

On the back surface of the front panel 7 formed by the injection molding method,
Are formed at a predetermined interval, and the tips of the projections 8, 8 are fixed to the thin rubber layer 4 by adhesion. The projections 8, 8,. In addition to increasing the flexibility of the front panel 7 and alleviating the impact, when a force is applied to the surface of the front panel 7 from an oblique direction, the front panel 7 is deformed so as to be twisted, thereby absorbing and relaxing this force.

Such an action is similar to that of natural leather. Reference numeral 9 denotes an inclined thin portion formed on the periphery of the front panel 7.

 The specific structure of the projections 8, 8,... Will be described below.

(A) Circular projections (FIGS. 3A and B) Assuming that the intervals between the projections 8 are p in the X-axis direction and q in the Y-axis direction and the diameter of the projections 8 is a, the arrangement is such that p = q> a. Is done. Where p = q = 1.5 to 2.5 mm, a = 0.5 to 2.0
mm. The thickness t of the surface layer 10 of the front panel 7 and the height h of the projection 8 are t = 0.5 to 1.5 mm and h = 0.
It can be 5 to 1.5 mm. These values are the same in the following examples. In the above structure, the surface S located on the projection 8 of the front panel 7 may be quickly stained during repeated use, and a spot-like stain pattern may appear. In addition, a cut may be formed at the base of the projection 8.

(B) Quadrangular projection (FIGS. 4A and 4B) A projection 11 having a quadrangular shape, for example, a square cross section, is formed on the back surface of the front panel 7. In such a structure, the same advantages as in the example shown in FIG. 3 can be obtained. Similarly, square spot-like stains may appear on the surface S of the front panel 7 located on the protrusions 11, or a cut may be formed in the base of the protrusions 11.

(C) A circular projection having a base at its base (FIG. 5)
(A, B) The circular projection 8 has a base 12 formed with a radius 12. Here, assuming that the diameter of the round portion 12 is b, p = q> b
> A. Thus, the presence of the round portion 12 reduces the contamination of the surface S on the projection 8 and also makes it difficult to form a cut at the base of the projection 8.

(D) Connected radius portions (FIGS. 6A and B) A structure in which projections 8,8... Are arranged densely so that adjacent radius portions 12,12. Have the relationship With this structure, the occurrence of spot-like stains on the surface of the front panel 7 is further suppressed, but is still insufficient because the back surface s of the surface layer 10 that cannot be covered by the round portion 12 is quite wide.

(E) The rows of the projections are alternately shifted (FIGS. 7A, B). The sizes and the intervals of the projections 8, 8,... And the round portions 12, 12,. B> a. With this structure, the area of the back surface s of the surface layer 10 that cannot be covered by the radius portion 12 can be minimized. As a result, the stain on the surface of the front panel 7 is almost inconspicuous when corresponding to the projections 8, and there is no break at the base of the projections 8.

FIG. 8 shows that in each of the above specific examples, a large-diameter portion 13 was formed at the lower end of the projection 8 to increase the bonding area with the thin rubber layer 4 or the reinforcing layer 3 to improve the bonding strength. is there.

FIG. 9 shows a front panel 7 according to the present invention, which is formed in a substantially hexagonal shape with outwardly curved sides, and has a slanted thin portion 9 in the periphery. The front panel 7 includes a white portion 14 as another portion, and a printing portion 15 displaying symbols, characters, patterns, and the like in black.

FIG. 10 shows a cross section of the front panel 7 in which the printing section 15 is formed by transferring a foil, and this is a mold shown in FIG.
Formed by 16,17. That is, it comprises a mold 16 forming the front surface of the panel 7 and a mold 17 forming the back surface, and sandwiches the printing foil 19 applied on the base film 18 between the two molds 16, 17. Nozzle 2 with molds 16 and 17 overlapped
From 0, the thermoplastic elastomer constituting the white portion 14 is injected and injected. On the cavity surface of the mold 16, a grain resembling the surface pattern of natural leather is formed, and on the cavity surface of the mold 17, a negative mold of the projection 8 is formed. Thereby, the front panel 7 having the structure shown in FIG. 10 is formed.

FIG. 12 shows a cross-sectional structure in which the printed portion 15 of the front panel 7 is formed by a two-color molding method.

In such a structure, the printing portion 15 extends not only to the front surface of the panel but also to the back surface, so that even if the front surface is worn, the printing portion 15 does not disappear. 13 (A) and 13 (B) show a method of manufacturing the front panel 7 having the above structure.
Mold 21 having a cavity 20 of the shape shown in FIG.
The mold 22 forming the back surface is superimposed, and a black thermoplastic elastomer is injected and injected from the nozzle 23. next,
The mold 21 is removed, and another mold 24 having a panel surface shape is superimposed on the mold 22. The black printed portion 15 is still formed in the mold 22 cavity. In this state, a white thermoplastic elastomer is injected and injected from another nozzle 25. Thus, the front panel 7 having the structure shown in FIG. 12 is formed.

Generally, in the case of a ball having a structure in which a large number of leather panels whose edges are cut off are adhered, the bound height is different between the case where the center of the leather panel collides with the ground and the case where the periphery collides with the ground. It is known that they are different, and the bounce is higher in the central part of the panel than in the peripheral part of the panel. For example, a soccer ball with the above structure 1.
It has been confirmed that when dropped from a height of 8 m, a difference of about 5 to 7 cm occurs between the two bound heights.
The present invention employs the following structure in order to eliminate such a difference between the ball heights of the bounce height.

That is, as shown in FIG. 14, the density of the projections 8 at the center of the surface panel 7 is increased, and the density is reduced toward the periphery. Thus, the bounce is low in the central portion of the high-density surface panel 7 and the bounce is high in the peripheral portion of the low-density surface panel 7, whereby the difference between the two is canceled out, and a substantially uniform bound height can be obtained. it can.

FIG. 15 shows another structure which achieves the same purpose, in which the thickness of the surface panel 7 is increased toward the periphery, and accordingly, the length of the projection 8 is increased toward the periphery. It was lengthened. Thus, the center portion of the front panel 7 is hard and therefore low bound, and the peripheral portion is soft and high bound, so that the height of the bound can be adjusted. The surface panel 7 having such a structure is suitable when a high-hardness plastic compound such as polyvinyl chloride having a JIS hardness of about 80 is used.

FIG. 16 shows still another structure which achieves the same purpose, in which the thickness of the surface panel 7 is increased toward the periphery,
In response to this, the thickness of the surface layer 10 is increased toward the peripheral portion. Therefore, in this case, the length of the projection 8 is uniform. Such a structure is suitable when using a plastic compound having a low hardness, for example, polyvinyl chloride having a JIS hardness of about 60, and since the surface layer 10 is soft,
The thickness of the peripheral portion of the surface panel 7 is soft and therefore high in the periphery thereof, while the thickness of the central portion of the surface panel 7 is hard and therefore low and both are adjusted to be equal. Further, the front panel having the structure shown in FIGS. 15 and 16 has an advantage that the peripheral portion is thickened, the groove formed by the edge-cut portion is deep, and the contrast is clear.

FIG. 17 and FIG.
This shows a structure in which two hexagonal surface panels 26A and 26B are connected. Each of the hexagonal surface panels 26A and 26B has an outwardly curved curve, and is connected at a central portion of any one side. In this structure, one may be a hexagonal surface panel and the other may be a pentagonal surface panel. The reason why each side of the hexagonal surface panels 26A and 26B is curved outwardly is to bond the sides of adjacent surface panels when bonded to a carcass. The ratio of the length c of the central portion to the length d of one side of the hexagonal surface panel 26 can be c / d ≒ 1/2. In this example, d ≒
46mm, c ≒ 24mm.

As shown in FIG. 18 (A), the inclined thin portion 27 is composed of an outwardly curved steep inclined portion 28 and a flat portion 29, the total length of the inclined thin portion 27 is about 4 mm, and the width of the flat portion 29 is about 0.3 mm. It is. Numeral 30 denotes an adhesive margin formed in a strip shape on the peripheral portions of the rear surfaces of the front panels 26A and 26B, and has a width g of about 3 mm. This value is about 1mm ~ 4m
The range of m is appropriate. That is, if this value is smaller than about 1 mm, the adhesive strength of the peripheral parts of the surface panels 26A and 26B decreases, and if it is larger than about 4 mm, the adhesive strength increases, but since this part is solid, the comparison is made. After bonding strongly along a curved surface, it may be warped and peeled off, or the protrusion 31
There are problems such as a noticeable difference in hardness from other regions in which is formed.

In the case of this example, since the distance from the center of the hexagonal surface panel 26A to the center of one side is about 40 mm, the width of about 1 to 4 mm of the bonding allowance 30 is 1/40 to 1/10 of the above distance. Become.

The flat portion 29 has flexibility due to its small thickness.
Therefore two face panels 2 joined as shown in FIG.
Even if an error occurs such that the flat portions 6 and 26 slightly overlap, the error can be absorbed by crushing the flat portions 29 and 29.

<Effects of the Invention> According to the present invention, the following effects can be obtained.

(A) Since the skin panel is formed by an injection molding method using a thermoplastic elastomer, a surface panel having an optimal shape as a ball skin can be manufactured. That is, it is possible to form a slender thin portion on the peripheral edge of the front panel, and at the same time, to form a large number of projections on the back surface of the front panel at a constant interval.

(B) By using a thermoplastic elastomer suitable for a ball surface panel, characteristics such as abrasion resistance, scratch resistance, weather resistance, and water absorption can be improved.

(C) By forming a large number of protrusions on the back surface of the front panel, the flexibility of the skin can be increased, and the impact when the ball hits the human body can be reduced. Further, due to the presence of the projections, when a force is applied to the panel surface from an oblique direction, the skin is deformed so as to be twisted, and fits appropriately to hands, feet, and the like. Therefore, a feeling similar to that of a sewing ball made of natural leather is obtained, and the responsiveness is extremely excellent even for advanced competition techniques.

(D) In addition, by forming a strip-shaped bonding margin around the rear surface of the front panel, it is possible to ensure the adhesion of the peripheral portion of the front panel, prevent the peeling thereof, and form a projection. Ball can maintain its maximum flexibility.

(E) When two or more hexagonal surface panels for a soccer ball are connected, the connecting portion is located at the center of one side of the hexagon, so that when bonding this to the spherical carcass, The sides of the front panel coincide. Therefore, it is possible to shorten the work time for bonding the front panel and to simplify the work.

[Brief description of the drawings]

FIG. 1 is a front view showing the appearance of a soccer ball, FIG. 2 is a cross-sectional view taken along the line II of FIG. 1, FIG. 3 (A) is a cross-sectional view showing a first specific example of a front panel, 4B is a bottom view of the front panel of the same example, FIG. 4A is a cross-sectional view showing a second specific example of the front panel, and FIG. FIG. 5 (A) is a cross-sectional view showing a third specific example of the front panel, FIG. 5 (B) is a bottom view of the same front panel, and FIG. 4 (B) is a bottom view of the front panel of the same example, and FIG.
FIG. 7A is a sectional view showing a fifth specific example of the front panel;
FIG. 8B is a bottom view of the front panel, FIG. 8 is a cross-sectional view showing a projection, FIG. 9 is a front view of the front panel having a printing unit, and FIG. II-II line cross-sectional view, FIG. 11 is a cross-sectional view showing a mold structure for manufacturing the front panel having the structure shown in FIG. 10, FIG. 12 is a cross-sectional view showing another structure of the front panel, 13 (A) and 13 (B) are cross-sectional views showing a mold structure for manufacturing the surface panel having the structure shown in FIG. 12, and FIGS. 14 to 16 are cross-sectional views showing the structure of the front panel. FIG. 17 is a front view showing a state where two hexagonal surface panels are connected, FIG. 18 (A) is a sectional view taken along the line III-III of FIG. 17, and FIG. 17 (B) is a view IV-IV of FIG. FIG. 19 is a sectional view taken along a line, showing a joined state of the panels. 1 ... soccer ball, 2 ... tube 3 ... reinforcing layer, 4 ... rubber thin layer 5 ... skin layer, 7, 26A, 26B ... surface panel 8, 11, 31 ... protruding body, 12 ... Round part 14: White part, 15: Printing part

Claims (3)

(57) [Claims] 1. A carcass comprising a spherical hollow rubber tube filled with compressed air and a reinforcing layer formed on the surface of the tube, or a carcass formed by forming a thermoplastic elastomer having a reinforcing function into a spherical hollow body. A surface panel that is bonded to a plurality of balls directly or via a rubber thin layer to form a skin of a ball for ball games, wherein the surface panel is molded into a predetermined shape by injecting a thermoplastic elastomer material into an injection mold, and A surface panel for a ball for a ball game, comprising a slanted thin portion on the periphery thereof and a large number of projections on the back surface thereof. 2. The front panel for a ball game ball according to claim 1, wherein said front panel has a band-shaped bonding margin at a peripheral portion of a back surface thereof. 3. The surface panel according to claim 1, wherein the surface panel is a hexagonal surface panel for a soccer ball, wherein each piece of the hexagonal surface panel has an outwardly curved curve, and has a center portion on any one side. 3. A surface panel for a ball for ball use according to claim 1, wherein said surface panel is connected to a central portion of an arbitrary side of said hexagonal surface panel or pentagonal surface panel.