| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve such problems that in a water-glycol hydraulic fluid essentially composed of glycol such as ethylene glycol and propylene glycol and used for hydraulic equipment, even in the case when a rust preventive is added thereto, sometimes, corrosion of partial metal can not be perfectly suppressed, and sludge is produced, thus a filter is clogged, or, sometimes, a sealing material is swelled to deteriorate hardness and strength. <P>SOLUTION: By using glycerin and/or polyglycerol in an aqueous hydraulic fluid, the corrosion of a metallic member can be dominantly inhibited, and further, an influence on a sealing material can be reduced compared with the case of a hydraulic fluid only using glycerin. <P>COPYRIGHT: (C)2013,JPO&INPIT |
