| 摘要 |
PROBLEM TO BE SOLVED: To provide a tennis ball 1 that is provided with a seam part 4 that does not easily get polluted, hides the dirt even when polluted, and has a good sustainability. SOLUTION: This tennis ball 1 is provided with a core 2, two pieces of felt 3, and a seam part 4. The core 2 is hollow and is made of an elastic material and the felts 3 are composed of woven felt. Also the seam part 4 is located between the felts 3 and is formed by a rubber composition bridged above. The width of the seam part 4 is more than 0.2 mm and less than 3.0 mm and the tensile strength Tb of the seam material that composes the seam part 4 is set to be 14.7 Mpa or more. Additionally, the elongation at breakage Eb of the seam material is set to be 500% or more. Thus the seam part 4 does not easily get polluted, nor does it shows the dirt even when polluted. COPYRIGHT: (C)2004,JPO
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