Solid anti-friction devices – materials therefor – lubricant or se – Lubricants or separants for moving solid surfaces and... – Inorganic compound
Patent
1998-10-28
2000-07-04
Howard, Jacqueline V.
Solid anti-friction devices, materials therefor, lubricant or se
Lubricants or separants for moving solid surfaces and...
Inorganic compound
508175, 508179, 72 42, C10M12900, C10M12500
Patent
active
060838876
DESCRIPTION:
BRIEF SUMMARY
The present invention relates to a method for mechanical working of metals and other solid materials as well as glass with a cooling and lubricating composition containing a major portion of carbon dioxide and a minor portion of a polar lubricant containing at least one polar organic compound with at least one oxygen atom.
The patent application WO 90/03341 and WO 92/16464 disclose the use of carbon dioxide in mechanical working processes as a cooling and lubricating medium. In the latter application it is suggested to add an additional lubricating agent to carbon dioxide to further improve the lubrication and reduce the heat generated during the mechanical working. The lubricant shall be soluble or dispersable in liquid carbon dioxide. The only specific lubricant additive mentioned in the patent specification is a spindle oil, Crucolan 7, based on hydrocarbons with low viscosity. Although the additions of spindle oils to carbon dioxide improves the total lubrication effect, the wear of the tool and the heat gene-rated are unacceptable. A substantial improvment must be achieved to turn the carbon dioxide based cooling and lubrication composition commercially competetive with other lubrication systems.
Therefore, the main object of this invention is to find an additive which essentially improves the lubrication of the carbon dioxide. Another object is to select additives which are not toxic to human beings or the environment and do not easily decompose into harmful gases or aerosols.
It has now surprisingly been found that these objects can be met by performing the mechanical working of metal and other solid materials, such as ceramics and polymers, as well as glass in the presence of carbon dioxide in liquid form in mixture with a polar organic compound containing oxygen atoms as heteroatoms with a boiling temperature over 200.degree. C. The amount of the polar organic compound added may vary within wide limits but is normally within the range of from 0.1 to 20, preferably from 0.5 to 4% by weight of the amount of carbon dioxide added. Preferably the organic compound has a boiling temperature above 250.degree. C. and a melting point below 5.degree. C., preferably below -5.degree. C. The organic compound is soluble or dispersable in the liquid carbon dioxide and contains at least one polar group selected from the group consisting of the ether, hydroxyl, carboxyl, ester and amido group or mixtures thereof.
Suitable and prefered polar organic compounds are alcohols with a molecular weight of 130-280, preferably 140-200; carboxylic acids with molecular weights from 140-320, preferably 150-290; alkylethercarboxylic acids with molecular weights from 155-1000, preferably 170-600; polyols or ethers and esters thereof with molecular weights from 140-1000, preferably 140-800; esters of fatty acids or phosphoric acids with molecular weights from 155-400, preferably 165-350; and alkanolamides between monocarboxylic acids and alkanolamines or alkoxylates thereof, having molecular weights of 180 to 1000, preferably 230-700.
Suitable examples of useful organic compounds according to the present invention are those having the formula R.sub.1 OH, where R.sub.1 is a branched or straight, saturated or unsaturated, aliphatic or acyl group with 9-18 carbon atoms such as branched alkyl groups having 9-15 carbon atoms or branched acyl groups. Other examples are ester compounds with the formula R.sub.2 COOR.sub.3, where R.sub.2 CO is an acyl group, preferably a branched or unsaturated acyl group with 10-20 carbon atoms, like oleyl and isostearyl, and R.sub.3 is an alkyl group with 1-4 carbon atoms. Still another group of preferred organic compounds are those having the formula R.sub.4 (A).sub.n OR.sub.5, where R.sub.4 and R.sub.5 are, independently of each other, hydrogen, an acyl group or an alkyl group with 1-20 carbon atoms, A is an oxyalkylene group with 2-4 carbon atoms and n is a number from 2-18. Preferably one or two of the groups R.sub.4 and R.sub.5 are hydrogen. Still another group of preferred organic compounds are tho
REFERENCES:
patent: 4118331 (1978-10-01), Jahnke
patent: 4475938 (1984-10-01), Knoth
patent: 4770780 (1988-09-01), Moses
patent: 5028363 (1991-07-01), Nishio et al.
patent: 5050532 (1991-09-01), Ruppert
patent: 5375426 (1994-12-01), Burgener
patent: 5401428 (1995-03-01), Kalota et al.
patent: 5616544 (1997-04-01), Kalota et al.
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