PREVENTING AGENT FOR DETERIORATION OF EMULSIFIED TYPE WORKING OIL AND METHOD FOR PREVENTING EMULSIFIED TYPE WORKING OIL FROM DETERIORATING USING THE SAME

摘要

PURPOSE:To obtain the subject preventing agent, containing a culture of a specific microorganism such as Aerococcus viridans BC-A-4 as an active component and capable of preventing putrefying bacteria from propagating and prolonging the exchange life of a working oil such as an emulsified type cutting oil or a grinding oil used for a metal working, etc. CONSTITUTION:This preventing agent contains a culture of Aerococcus viridans BC-A-4 (FERM P-14172), Bacillus brevis BC-A-69 (FERM P-14171) or Bacillus brevis BC-A-3124 (FERM P-14173) as an active component. Furthermore, the culture is preferably the one prepared by culturing the bacterium in a culture medium containing an emulsified type working oil to be an object of treatment, a pH adjustor and a 0.0001-0.001wt.% saline solution containing a bi- to a trivalent iron compound. The pH of the culture medium is preferably within the range of 9.0-9.5.