To solve problems of a retainer material of a polishing object wherein bubbles are produced in polishing the polishing object due to dispersion stabilizer and wet type solidification auxiliary of various types of surfactant to reduce the quality of the polishing object and deteriorate the yield of the product.

This retainer material of the polishing object is characterized in that the quantity of the surfactant included in the retainer material of 5.0 mg/g retainer material or less or the bubbles produced from the retainer material during the polishing are 5 bubbles/5400 mm2 or less. A skin layer formed on the bubble layer surface of the retainer material is buffed.