Abstract: An acrylic rubber including: a polymer composition of: 70 to 99.9% by weight of a bonding unit derived from at least one (meth) acrylic acid ester selected from (meth) acrylic acid alkyl ester and (meth) acrylic acid alkoxyalkyl ester; 0.1 to 10% by weight of a bonding unit derived from a monomer containing a reactive group; and 0 to 20% by weight of a bonding unit derived from other monomer, wherein ash content is 0.15% by weight or less, total amount of sodium and sulfur in the ash is 60% by weight or more, a ratio of sodium to sulfur by weight ratio is in the range of 0.5 to 2.5, ratio of Z-average molecular weight to weight average molecular weight is 1.3 or more, and weight average molecular weight is in the range of 1,000,000 to 5,000,000.

Abstract: An acrylic rubber bale excellent in storage stability and water resistance and a method for producing the same are provided. An acrylic rubber bale, including an acrylic rubber having a reactive group, with a specific ash content, a large proportion of magnesium and phosphorus in the ash, and a specific ratio of magnesium and phosphorus, is highly excellent in storage stability and water resistance. This acrylic rubber bale can be produced by using a specific stabilizer and a specific coagulant in an emulsion polymerization process of an acrylic rubber and performing a process from coagulation process to baling process under specific conditions.

Abstract: An acrylic rubber sheet excellent in storage stability and water resistance, a method for producing the same, a rubber mixture containing the acrylic rubber sheet and a rubber cross-linked product thereof are provided. The acrylic rubber sheet according to the present invention includes an acrylic rubber having a reactive group and having a weight average molecular weight (Mw), a ratio of a Z-average molecular weight (Mz) and a weight average molecular weight (Mw) in a specific range. The acrylic rubber sheet according to the present invention has an ash content of 0.2% by weight or less, an amount of gel insoluble in methyl ethyl ketone is 50% by weight or less, and a water content of less than 1% by weight, and is excellent in water resistance and highly well-balanced in strength properties and processability.