Method for manufacturing highly transparent, highly resilient balls and highly transparent, highly resilient balls

Abstract

To provide a highly transparent, high-rebound ball that can utilize as many conventional materials and manufacturing processes as possible. [Solution] A rubber compound formed into a sheet by kneading together 73% low-cis polybutadiene rubber, 26% softener, and 1% sulfurizing agent is filled into a mold and vulcanized at a temperature of 160 degrees for 30 minutes, thereby obtaining a highly resilient ball with unprecedented transparency. The illustration 2 printed at an appropriate position on the outer surface of the main body 1 is magnified on the opposite side of the printed surface of the illustration 2, making it clearly visible in a way that is different from conventional designs.

Description

Technical Field

[0001] The present invention relates to a high-rebound ball so-called a bouncy ball, and particularly relates to one having improved transparency and the like.

Background Art

[0002] As is well known, a high-rebound ball so-called a bouncy ball is variously used as a game ball for children and as a target of so-called ball scooping at festivals and street fairs (see, for example, Patent Document 1). Furthermore, in such a bouncy ball, there are some in which various patterns, illustrations, etc. are applied to the outer peripheral surface or the inside thereof to enhance the decorativeness.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, conventionally, not only manufacturers of bouncy balls but also purchasers have a strong tendency and recognition to emphasize playability as a game ball or a target of ball scooping, and a low tendency to be oriented toward decorativeness. Therefore, the demand for transparency is not so high, and as a result, it has not been sufficient to arouse the purchase desire as a decorative item. For example, it is possible to obtain a highly transparent bouncy ball by adding a new material or component capable of obtaining high transparency to a conventional material, but in this case, it will lead to an increase in manufacturing cost, so it is not realistic.

[0005] On the other hand, manufacturers have not previously dedicated sufficient effort or time to pursuing transparency based on conventional materials, resulting in a lack of accumulated technical expertise. In light of the current situation, the inventors of this invention have diligently researched a method for manufacturing highly transparent, highly resilient spheres that utilizes as many conventional materials and manufacturing processes as possible. As a result, they have found a manufacturing method that can achieve high transparency. However, they have also discovered that printing illustrations or other designs onto highly transparent, highly resilient spheres in the same way as before leads to a decrease in transparency, indicating a trade-off between pursuing transparency and maintaining print quality.

[0006] This invention has been made in view of the above circumstances, and provides a method for manufacturing a highly transparent, highly resilient ball that can use as many conventional materials and manufacturing processes as possible, and a highly transparent, highly resilient ball. [Means for solving the problem]

[0007] To achieve the above objectives of the present invention, the method for manufacturing a highly transparent, highly resilient sphere according to the present invention is: A method for producing highly transparent, highly resilient spheres mainly composed of low-cis polybutadiene rubber, The first step involves kneading the aforementioned low-cis polybutadiene rubber in a mixture of 73%, a softener in 26%, and a sulfurizing agent in 1% to obtain a sheet-like rubber compound. The invention comprises a second step of filling a mold with the aforementioned rubber compound and vulcanizing it at a temperature of 160 degrees Celsius for 30 minutes. Furthermore, in order to achieve the above-mentioned objectives of the present invention, the highly transparent, highly resilient sphere according to the present invention is A highly transparent, highly resilient ball made primarily of low-cis polybutadiene rubber, The highly transparent, highly resilient sphere consists of a spherical body. The aforementioned main body is This is obtained by vulcanizing a rubber compound containing 73% of the low-cis polybutadiene rubber, 26% of a softener, and 1% of a sulfurizing agent at a temperature of 160 degrees Celsius for 30 minutes. [Effects of the Invention]

[0008] As described above, the present invention provides the effect of being able to obtain highly transparent and highly resilient spheres without significantly altering the conventional manufacturing process by changing the temperature and time in the vulcanization process, and providing highly transparent and highly resilient spheres that are more decorative than conventional spheres. [Brief explanation of the drawing]

[0009] [Figure 1] This is a front view of a highly transparent, highly resilient sphere according to an embodiment of the present invention. [Figure 2] This is a rear view of a highly transparent, highly resilient sphere according to an embodiment of the present invention. [Figure 3] This is an overall perspective view of the highly transparent, highly resilient sphere in an embodiment of the present invention, on the side opposite to the side with the illustration printed on it. [Figure 4] This is an overall perspective view of the illustration-printed side of a highly transparent, high-rebound sphere according to an embodiment of the present invention. [Figure 5] This is an overall perspective view showing an example of how the highly transparent, highly resilient spheres of the present invention can be used as decorative items. [Modes for carrying out the invention]

[0010] Hereinafter, embodiments of the present invention will be described with reference to Figures 1 to 5. The components, arrangements, etc., described below are not intended to limit the present invention and can be modified in various ways within the scope of the spirit of the present invention. In the embodiment of the present invention, the highly transparent, highly resilient sphere (hereinafter referred to as "the sphere in this embodiment" for convenience of explanation) is formed by printing Illustration 2 on a desired location on the outer surface of a spherical body 1 (see Figure 2). This ball, through the manufacturing procedure described later, possesses significantly greater transparency compared to conventional high-rebound balls of this type. As a result, Illustration 2 printed on the outer surface of this ball can be clearly seen when reversed horizontally and enlarged on the opposite side of the printed surface (see Figure 1). Note that FIG. 1 is a front view of the present embodiment ball as seen from the side opposite to the printing surface of Illustration 2, and FIG. 2 is a rear view of the present embodiment ball as seen from the printing surface side of Illustration 2.

[0011] Next, a method for manufacturing a highly transparent and highly resilient ball according to an embodiment of the present invention will be described. First, the manufacturing process of the present embodiment ball is basically the same as that of the conventional highly resilient ball manufacturing process, but in order to ensure higher transparency than the conventional one, the processes as described below are required. Specifically described below, first, as in the conventional method, the materials are mixed and kneaded. The present embodiment ball uses low-cis polybutadiene rubber, a softening agent, and a vulcanizing agent as materials, and those kneaded with a blending ratio of 73% of low-cis polybutadiene rubber, 26% of the softening agent, and 1% of the vulcanizing agent are used for molding.

[0012] After kneading, it is made into a rubber pound formed into a required sheet shape. Next, the sheet-shaped rubber pound is set (filled) in a mold using a press machine. Note that two molds are required for one present embodiment ball. That is, there are two molds in total, namely, a mold (upper mold) in which a hemispherical cavity corresponding to the upper half of the ball is formed, and a mold (lower mold) in which a hemispherical cavity corresponding to the lower half of the ball is formed.

[0013] After the above-mentioned sheets are set in the required number of molds, the upper and lower molds are combined and placed in an oven for vulcanization. That is, heating and molding are performed at a temperature of 160 degrees for 30 minutes. Note that this vulcanization time of 30 minutes is the time required when the diameter of the present embodiment ball is 43 mm. )2]]In addition, in the case of the present embodiment ball, the molds used for this heating and molding are made of steel, both the upper mold and the lower mold have a plate thickness of 32 mm, the overall outer dimension is 380 mm × 380 mm, and the number of balls is 59.

[0014] Here, the difference between the vulcanization in the manufacturing process of the conventional highly resilient ball and the vulcanization in the embodiment of the present invention will be described. First, when manufacturing a conventional high-rebound ball with a diameter similar to that of the present embodiment ball, the vulcanization time is approximately a little over 10 minutes. In addition, the mold used for heating and molding the conventional high-rebound ball is made of steel. The thickness of the upper mold is 25 mm, the thickness of the lower mold is 27 mm, the overall outer dimensions are 447 mm × 395 mm, and the number of balls is 72.

[0015] Conventional high-rebound balls were mostly used, for example, in ball scooping at festivals, etc., by applying a single color or multiple colors to make them colored balls, or by mixing in sequins, etc. inside. Therefore, the need for transparency was low, and the atmosphere of aiming for improved transparency on the part of the manufacturing manufacturers was also low. The transparency of such conventional high-rebound balls, for example, in a state where sequins, etc. are mixed inside, although the sequins, etc. mixed inside can be somewhat visually recognized, since the original transparency is not very high, it is undeniable that many of them have a slightly turbid feeling as a whole.

[0016] In view of such a situation, the inventor of the present application aimed to create new needs for so-called bouncy balls, and as one of the measures to enhance the value as a decoration not found in the past, from the perspective that it is necessary to ensure transparency far superior to the conventional ones, as a result of earnestly researching the relationship between vulcanization and transparency, it has reached the conclusion that it is possible to obtain a high transparency not found in the past at the above-mentioned temperature and vulcanization time. Regarding the transparency of the present embodiment ball, a simple sensory test was conducted, and the following results were obtained. First, no information was presented to the test subjects in advance regarding the present embodiment ball that was the test object. The test object was browsed as a new product, and a simple sensory test was conducted.

[0017] As the impressions of the test subjects after browsing, they had the recognition that it might be a glass product at first glance, but felt a slight sense of discomfort regarding the texture and did not reach the conclusion that it was a glass product. On the other hand, it was close to the form of a conventional bouncy ball, but due to its transparency, it could not be determined as a bouncy ball. Thus, by undergoing the vulcanization process described above, this prototype ball possesses a significantly higher level of transparency compared to conventional bouncy balls. After the vulcanization process is complete, the molded sphere is removed from the mold after the required cooling. Then, as in the conventional process, finishing steps such as removing burrs and applying silicone spray for surface protection are performed to complete the molding of the highly transparent, high-rebound sphere.

[0018] Next, we will explain the process for printing on such highly transparent, highly resilient spheres. First, the printing on the actual sphere is performed, for example, to apply the desired illustration 2 to an appropriate position on the outer surface, as shown in Figure 2. Printing on this sphere will be done using pad printing, which is suitable for printing on spheres. To explain the printing procedure in detail, first, the surface of the actual sphere is cleaned using a neutral detergent.

[0019] Next, the actual spheres are immersed in a surface treatment solution for surface treatment. The purpose of immersing the actual ball in the surface treatment solution is to improve ink adhesion by creating microscopic scratches (irregularities) on the surface of the ball. Immerse the test ball in the surface treatment solution for 8 seconds. Here, the surface treatment solution is a mixture of a treatment solvent and water in a 1:1 ratio. The aforementioned treatment solvent is specifically a mixture of 75% toluene solution and 25% chlorinated polypropylene.

[0020] The specific amount of surface treatment solution required depends on the number of spheres being treated, and is not limited to a particular amount. However, the required amount must be sufficient to completely immerse each sphere in the surface treatment solution during the treatment process. Therefore, for example, if 1 liter of surface treatment solution is required, the amount of treatment solution and water described above will be 500 mL each. The surface treatment solution is preferably at room temperature.

[0021] Incidentally, in the case of conventional high-rebound balls where transparency is not a priority, the immersion time in the surface treatment solution was about 13 seconds. With conventional surface treatments like these, a large number of microscopic scratches are formed on the surface of the sphere, making it impossible to ensure the transparency of the sphere. Furthermore, the adhesion of the printing ink is poor, resulting in low print quality.

[0022] Therefore, the inventors of this application diligently conducted various tests and studies on the effects of the components of the surface treatment solution and the treatment time on the transparency and ink fixation of the spheres in question. As a result, they discovered the above-mentioned components of the surface treatment solution and treatment time that can maintain good ink fixation without significantly reducing transparency. Furthermore, when the immersion time of the sample ball in the aforementioned surface treatment solution was reduced to, for example, 10 seconds, it was immediately apparent that numerous minute scratches had formed on the surface of the sample ball, and naturally, its transparency also decreased significantly.

[0023] After the surface treatment described above, the test ball is dried, and then pad printing is performed using a pad printing machine. Pad printing itself is a well-known printing method, and the pad printing on this ball is based on conventional methods and does not differ in any particular way, so a detailed explanation will be omitted. Pad printing on a sphere is typically performed hemisphere by hemisphere. That is, for example, if illustration 2 of the sphere in this example is drawn on the entire outer surface of the main body 1, pad printing will be performed hemisphere by hemisphere. On the other hand, if illustration 2 is only on the hemispherical side, the printing process will be completed by pad printing on the hemisphere. In addition, for multi-color printing, the printing process is carried out one color at a time. After the desired printing is complete and the surface is dried, a protective silicone coating is applied to the entire sphere to finish the process.

[0024] However, due to its high transparency, this prototype sphere, unlike conventional designs, allows users to enjoy illustration 2 printed on its outer surface in a horizontally flipped and enlarged state when viewed from the opposite side of the printed surface (see Figure 1). Furthermore, the printing on the outer surface of the actual sphere is not limited to Illustration 2; instead, for example, a QR code (registered trademark) may be printed. In this case, the QR code (registered trademark) is preferably one that contains information such as the URL (Uniform Resource Locator) of a specific internet site or information about a specific application. In other words, if a QR code (registered trademark) encodes information about the URL of a specific internet site, scanning that QR code (registered trademark) with a smartphone allows access to a specific site on the internet, enabling users to view information such as that related to highly transparent, high-rebound spheres.

[0025] Furthermore, if the QR code (registered trademark) contains information about a specific application installed and used on a smartphone, scanning that QR code (registered trademark) with a smartphone will launch the required application pre-installed on the smartphone, allowing users to, for example, enjoy games while viewing the actual ball on their smartphone screen.

[0026] Furthermore, as mentioned earlier, this ball differs from conventional high-rebound balls in that it has high transparency, making it perfectly suitable for use as a decorative item. In other words, for example, as shown in Figure 5, a configuration in which multiple of these spheres are housed in a transparent cylindrical case 10 is suitable as a tabletop decorative item. Note that in Figure 5, illustration 2 (see Figures 1 and 2) for the outer surface of the main body 1 has been omitted to make the drawing easier to read and understand; however, in reality, the necessary illustrations will be printed and used. [Industrial applicability]

[0027] This technology can be applied to high-rebound balls that require significantly higher transparency than conventional balls. [Explanation of symbols]

[0028] 1…Main unit 2…Illustration 10…Cylindrical transparent case

Claims

1. A method for producing highly transparent, highly resilient spheres mainly composed of low-cis polybutadiene rubber, The first step involves kneading the aforementioned low-cis polybutadiene rubber in a mixture of 73%, a softener in 26%, and a sulfurizing agent in 1% to obtain a sheet-like rubber compound. A second step involves filling a mold with the aforementioned rubber compound and performing vulcanization at a temperature of 160 degrees Celsius for 30 minutes. A method for producing a highly transparent, highly resilient sphere, characterized by having the following:

2. The method for manufacturing a highly transparent, highly resilient sphere according to claim 1, characterized in that the mold comprises two parts, an upper mold and a lower mold, each having a hemispherical cavity formed in it, the diameter of the spherical cavity formed by combining the upper mold and the lower mold being set to 43 mm, the upper mold and the lower mold each being made of steel with a plate thickness of 32 mm, each having an external dimension of 380 mm x 380 mm, and 59 of the hemispherical cavities being provided.

3. A highly transparent, highly resilient ball made primarily of low-cis polybutadiene rubber, The highly transparent, highly resilient sphere consists of a spherical body. The aforementioned main body is A highly transparent, high-rebound ball characterized by being obtained by vulcanizing a rubber compound containing 73% of the aforementioned low-cis polybutadiene rubber, 26% of a softening agent, and 1% of a sulfidating agent at a temperature of 160 degrees Celsius for 30 minutes.

4. A method for printing on a highly transparent, highly resilient ball manufactured by the method for manufacturing a highly transparent, highly resilient ball described in claim 1 or claim 2, or a method for printing on a highly transparent, highly resilient ball described in claim 3, A method for printing a highly transparent, highly resilient sphere, characterized in that, when applying a desired illustration to the outer surface of the main body of the highly transparent, highly resilient sphere by pad printing, the main body is immersed for 8 seconds in a surface treatment solution prepared by mixing a treatment solvent consisting of 75% toluene solution and 25% chlorinated polypropylene with water in a 1:1 ratio, and then the desired illustration is pad printed.

5. The outer surface of the main body is decorated with a desired illustration. The aforementioned illustration is The highly transparent, highly resilient sphere according to claim 3, characterized in that the main body is pad-printed after being immersed for 8 seconds in a surface treatment solution which is a mixture of a treatment solvent consisting of 75% toluene solution and 25% chlorinated polypropylene and water in a 1:1 ratio.

Images