JPS59125574A - Air contained ball and production thereof - 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 The present invention relates to an air-filled ball for ball games and a manufacturing method.

Various methods have been used to manufacture this type of ball in the past, but all of them have advantages and disadvantages, and many of them are particularly unsatisfactory in terms of cost. For example, there is a multilayer method, but this requires a long process because it is completed by overlapping the bladder 1 reinforcing layer and the rubber layer 1 surface layer, and production costs are high because defective products occur in each process. It had the disadvantage of poor productivity.

In addition, the method of attaching the bowl is to make the bowl by injection, and although this process can be done in a short time, there is a subsequent adhesion process that requires advanced technology, and the bowl has a material grain orientation. This creates a difference in stress, causing deformation and uneven rebound height when air is introduced.

Furthermore, as another conventional example, a method was used in which a product was obtained by heating rotational molding using polyether elanuttomer as a raw material in a sealed spherical mold, but this cost the raw material approximately 2,000 yen/kQ. There were two problems: it was expensive and it was expensive.

The air-filled ball and manufacturing method according to the present invention eliminates the drawbacks of the conventional method, and its gist is that a certain amount of thermoplastic polyvinyl chloride compound is filled into a sealed spherical mold, The product is heated while being rotated to adhere to the inner surface of the mold to a uniform thickness and gel, and then the mold is cooled and divided, after which the air-filled pole body of the product is taken out.

The air-filled ball thus obtained can be used as a play pole as it is, or the pole body can be treated with a primer and natural or synthetic leather can be pasted with an adhesive (such as chloroprene). to obtain a leather ball pole. A rubber-covered ball can also be obtained by attaching rubber instead of leather.

The drawings show embodiments of the invention, 1a, 11)
2 is a split-type sealed spherical mold, 2 is an air-filled ball obtained by rotation molding in the sealed mold, and 3 is a rubber holder.

FIGS. 3 and 4 show a state in which a ball game pole with a beautiful geometric pattern is obtained by pasting a leather panel 4 of natural or synthetic leather on the surface of the pole body 20.

The raw material used in the pneumatic ball and manufacturing method of the present invention is 100 mesh powder of a compound composed of polyvinyl chloride with a degree of polymerization of 700 containing a tin-based stabilizer and a plasticizer, and this is molded into a mold. 1 a, , l
After the mixture was sealed in a container B, it was rotated in biaxial directions in a furnace heated to 300° C., and a good-shaped hollow vinyl pole with uniform wall thickness was obtained in about 20 minutes.

Incidentally, the price of the above PVC compound is about 3
00 yen/kq, which is about one-seventh the price of the polyester elanuttomer mentioned above, and is extremely advantageous in terms of cost reduction.

Further, in the method of the present invention, since the material is heated and molded by rotating in two axial directions, there is no grain of the material, so there is no deformation or rebound unevenness. Since it is a sphere, there is no need for an adhesion process, and the somewhat long time required for the heat molding process can be improved by increasing the number of molds without requiring an increase in manpower. Moreover, thickness unevenness can be solved by making the particle size of the raw material powder used small and uniform.

The vinyl pole material obtained using the above-mentioned raw materials had a strength of 1'70 kg/Cd and an elongation of 175 cm.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and Fig. 1 is a cross-sectional view of a mold and a product, Fig. 2 is a cross-sectional view of the product taken out from the mold, and Fig. 3 is a cross-sectional view of the product taken out from the mold. FIG. 4 is a partial sectional view of FIG. 3. l a, , l b Spherical mold 2 Pole body 4 Leather panel patent Applicant Molten Rubber Industries Co., Ltd. Agent Patent attorney Furu 1) Keimina Tsuyoshi 1
Side A-Z Eye +30 Saijuhan 429-

Claims (1)

[Claims] l An air-filled ball obtained by rotary heating molding thermoplastic polyvinyl chloride powder in a sealed mold. 2. A pneumatic ball for ball games in which a skin of natural or synthetic leather is adhered to the surface of the pneumatic ball body obtained by rotary heating molding thermoplastic polyvinyl chloride powder in a sealed mold. 3. A method for producing an air-filled ball obtained by rotary heat molding thermoplastic polyvinyl chloride powder in a sealed spherical mold.