ANTITARNISH AGENT FOR LEAD-CONTAINING ALLOY, WATER-BASE CLEANER COMPOSITION, RINSING AGENT, WATER-BASE CLEANING METHOD, AND WATER RINSING METHOD

摘要

PROBLEM TO BE SOLVED: To provide an additive for preventing discoloration of a lead-containing alloy represented by free cutting steel in the step of cleaning with a water-base cleaner or water-rinsing an optical component, an electronic component, a metal component or a ceramic component mounting a component made of the alloy, or the single component made of the alloy.;SOLUTION: The antitarnish agent to be used for the lead-containing alloy comprises at least one of a carbonate expressed by the general formula (1): M_aH_b(CO₃)_n, (wherein a is 1 or 2; b is an integer of 0 to 2; n is 1 or 2; M is a metal atom having greater ionization tendency than lead has, or a volatile organic base; and H is a hydrogen atom), and at least one of nitrogen-based heterocyclic compounds; and has a ratio of carbonate/nitrogen-based heterocyclic compound (by a weight ratio) of 0.001 to 10,000.;COPYRIGHT: (C)2005,JPO&NCIPI