- Degrease when cold or hot, or in the vapor state.
- Non flammable
- Chemically inert to metals
- Stable
- Nontoxic
- Boiling point under 125 oC
- Low specific heat and latent heat of vaporization
- Vapors heavier than air
- Liquid phase of high specific gravity and low surface tension
- Meet air pollution requirements
- Be acceptable under the Occupational Safety and Health Act Standard
By addition of oil-soluble emulsifiers to solvents to solvent-emulsion cleaners are produced. These are reported to afford very good removal of solid soils when used as diphase cleaners; they involve simultaneous contact of surface with water and a solvent that preferentially wets the metal. This system is particularly useful in removing dust and other solid particles mixed with oils and greases or pigmented drawing and buffing compounds. The metal still retains an oil film, however, so that it is necessary to alkaline clean before electroplating. A preliminary solvent emulsion treatment greatly decreases the load on the final cleaning bath. Care must be taken to remove all the solvent cleaner from recesses in metal parts before they are placed in the plating bath, or trouble will be encountered with plating solutions that contain surface active agents.
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