Rubber composition for hollow ball and hollow ball

A method for producing a rubber composition for a hollow ball, the method comprising:

• a first step of mixing a base rubber and a carbon-based filler having a degree of flatness particle diameter D50c (μm) of the carbon-based filler by an average thickness Tc (μm) of the carbon-based filler;
• and
• a second step of adding an inorganic DLc of not less than 110, to obtain a master batch, the degree of flatness DLc being obtained by dividing an average filler composed of particles to the master batch to orient the particles that form the inorganic filler, in the base rubber, wherein
• a weight ratio Mc/Mi of an amount Mc of the carbon-based filler to an amount Mi of the inorganic filler is not less than 0.04 and not greater than 1.00,
• a degree of flatness DLi obtained by dividing an average particle diameter D50i (μm) of the inorganic filler by an average thickness Ti (μm) of the inorganic filler is not less than 20, and an amount of the inorganic filler per 100 parts by weight of the base rubber is not less than 1 parts by weight and not greater than 150 parts by weight.

A hollow ball comprising a hollow core formed from a rubber composition, wherein

• the rubber composition includes a base rubber, an inorganic filler composed of particles, and a carbon-based filler,
• a degree of flatness DLc obtained by dividing an average particle diameter D50c (μm) of the carbon-based filler by an average thickness Tc (μm) of the carbon-based filler is not less than 110,
• a weight ratio Mc/Mi of an amount Mc of the carbon-based filler to an amount Mi of the inorganic filler is not less than 0.04 and not greater than 1.00,
• a degree of flatness DLi obtained by dividing an average particle diameter D50i (μm) of the inorganic filler by an average thickness Ti (μm) of the inorganic filler is not less than 20, and an amount of the inorganic filler per 100 parts by weight of the base rubber is not less than 1 parts by weight and not greater than 150 parts by weight.