Patent ID: 8747688

Claim:
A glass disk processing method of polishing an inner peripheral face and an outer peripheral face of a glass disk, comprising the steps of: stacking glass disks about a rotary shaft for generating a glass disk stacked body in which a plurality of glass disks are stacked; preparing an inner peripheral etchant and an outer peripheral etchant, each comprising a fluorinated acid based material; continuously supplying the inner-peripheral etchant to the inner peripheral face of the glass disk stacked body via an inner space formed between said inner peripheral face and an outer peripheral face of the rotary shaft; and continuously supplying the outer-peripheral etchant to the outer peripheral face of the glass disk stacked body, wherein an etching rate of the inner-peripheral etchant and an etching rate of the outer-peripheral etchant are different from each other, and the etching rate of the inner-peripheral etchant is higher than the etching rate of the outer-peripheral etchant, and wherein the difference in the etching rate between the inner-peripheral etchant and the outer-peripheral etchant is realized by at least one method selected from variation in density of the fluorinated acid of the inner-peripheral etchant and the outer peripheral etchant, variation in temperature of the inner-peripheral etchant and the outer peripheral etchant, and variation in the kind of an additive in the inner-peripheral etchant and the outer-peripheral etchant.