Cleaning and liquid contact with solids – Processes – Oils – grease – tar – or wax removal – by dissolving
Patent
1993-11-19
1995-06-06
Lieberman, Paul
Cleaning and liquid contact with solids
Processes
Oils, grease, tar, or wax removal, by dissolving
134 2, 134 41, C23G 5032
Patent
active
054219078
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
This invention relates to the use of fatty acid-2-ethylhexyl esters as cold cleaning agents for predominantly oil-contaminated metal surfaces and to preparations containing these esters.
STATEMENT OF RELATED ART
Cold cleaning is a much-used process for the pretreatment and care of materials or end products. It is generally used to remove fats, oils, tar, bitumen, lubricants, waxes and similar hydrophobic materials from hard surfaces, particularly metal surfaces. However, other materials such as, for example, sand, dust, corrosion products or residues of various solvents may also be present among the substances to be removed. Cold cleaning is generally carried out at temperatures in the range from 10.degree. to 40.degree. C., the workpieces to be cleaned being washed with the cold cleaner and immersed, sprinkled, sprayed or otherwise contacted with the preparation.
Suitable cold cleaning preparations are halogenated hydrocarbons, such as for example 1,1,1-trichloroethane or methylene chloride. However, substances of this type are unsafe both for reasons of industrial hygiene and for ecological reasons and therefore necessitate elaborate safety measures and recovery measures for protecting human beings and the environment.
Accordingly, gasoline distillates are preferably used instead of halogenated hydrocarbons for cold cleaning. Although they are ecologically safer, gasoline distillates have a comparatively poor cleaning effect. Accordingly, it is proposed in German patent application DE 35 37 619 A1 to use 0.2 to 6% by weight solutions of fatty alkyl esters containing a total of 12 to 40 carbon atoms in gasoline distillates as cold cleaning preparations. Although the cleaning effect of preparations such as these is entirely satisfactory, serious doubts still exist for reasons of industrial hygiene and ecology, because the presence of gasoline distillates in the preparations on the one hand represents a potential inhalation-toxicity hazard and, on the other hand, contributes to serious COD pollution of wastewaters because of the poor biodegradability of such distillates.
DESCRIPTION OF THE INVENTION
Object of the Invention
Accordingly, the, problem addressed by the present invention was to provide new cold cleaning preparations for metal surfaces which would be free from the disadvantages mentioned above.
SUMMARY OF THE INVENTION
The present invention relates; to the use of fatty acid-2-ethylhexyl esters, optionally in admixture with emulsifiers, solubilizers, corrosion inhibitors and/or water, as cold cleaning preparations for predominantly oil-contaminated metal surfaces.
Although the suitability of fatty alkyl esters for cold cleaning is known in principle, it has surprisingly been found that a particularly advantageous cleaning effect can be obtained with fatty acid-2-ethylhexyl esters, optionally in combination with emulsifiers, solubilizers and corrosion inhibitors and/or water. The advantage of the invention is, above all, that there is no need to use gasoline distillates. Fatty acid-2-ethylhexyl esters and the preparations containing them are not toxic on inhalation, are completely biodegradable and have low viscosities. Since fatty acid-2-ethylhexyl esters have a particularly high affinity for metal surfaces, the surfaces are not completely degreased; instead a fine ester film is formed and affords additional desirable protection against corrosion.
Fatty acid-2-ethylhexyl esters are known substances which may be obtained by the relevant methods of preparative organic chemistry, for example by esterification of fatty acids with 2-ethylhexanol in the presence of p-toluene sulfonic acid or tin filings.
DESCRIPTION OF PREFERRED EMBODIMENTS
According to the invention, 2-ethylhexyl esters of fatty acids containing 6 to 22 carbon atoms and 0 or 1 double bond may be used. Typical examples are the 2-ethylhexyl esters of caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, elaidic acid, petroselic acid, arachic acid
REFERENCES:
patent: 4311531 (1982-01-01), Bege et al.
patent: 4518585 (1985-05-01), Greene et al.
patent: 4612058 (1986-09-01), Geke et al.
patent: 4704225 (1987-11-01), Stoufer
patent: 5100697 (1992-03-01), Nielsen
"Guerbet Alcohols, A Versatile Hydrophobe", A. J. O'Lenick, Jr. and R. E. Bilbo, Soap/Cosmetics/Chemical Specialties, p. 52 Apr. (1987).
Herold Claus-Peter
Mueller Heinz
Nieendick Claus
Schmid Karl
Douyon Lorna M.
Grandmaison Real J.
Henkel Kommanditgesellschaft auf Aktien
Jaeschke Wayne C.
Lieberman Paul
LandOfFree
Process for cold cleaning oil-contaminated metal surfaces with 2 does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process for cold cleaning oil-contaminated metal surfaces with 2, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for cold cleaning oil-contaminated metal surfaces with 2 will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-984189