| 摘要 |
PROBLEM TO BE SOLVED: To provide a cleaning method which has high detergency to the stain of sulfur-containing plastic lens resin having a refractive index of >=1.55, suppresses the corrosion of a forming glass die, has excellent safety to the living body in cleaning, and has excellent dye-affinity as well. SOLUTION: In cleaning a forming glass die used for the production of a sulfur-containing plastic lens having a refractive index of >=1.55, the cleaning method has a cleaning process using a cleaning agent containing (a) an 8 to 75 wt.% oxygen atom-containing monocyclic aromatic compound (exclusive of phenol, aromatic carboxylic acid and aromatic carboxylic ester) expressed by general formula (1) (wherein, R<1> is a hydrogen atom or a 1 to 6C hydrocarbon group; n is an integer of 1 to 4; X is a divalent or trivalent group in which the bonding hand of one piece (monovalence) combines with an aromatic ring, and the remaining bonding hands combine with Y; Y is a monovalent group; and m is an integer of 1 to 3), (b) a 0.3 to 20 wt.% inorganic alkali agent, (c) a calcium ion releasable substance of 0.005 to 5 wt.% [by an amount expressed in terms of calcium ions], and (d) 9 to 91 wt.% water. |
