LUBRICANT

Abstract: The invention relates to a lubricant concentrate composition, comprising one or more diamines and one or more quaternary ammonium compounds, or soluble salts thereof. The invention also relates to a method of lubricating a system, such as a bottle washing or a conveyor belt system, comprising the steps of diluting a lubricant concentrate composition according to invention, and passing the resulting diluted lubricant through the system. The invention further relates to a lubricant composition, obtainable by diluting the concentrate composition of the invention with water to a suitable use concentration.

Description: LUBRICANT Field of the invention The present invention relates to a lubricant concentrate composition and more particularly to a lubricant composition obtainable on diluting such a concentrate, which compositions have biocidal activity. Background of the invention Slat conveyor systems such as used in industrial bottle washing systems, need to be lubricated in order to ensure smooth running. Conveyor belt lubricants based on diamines are already known from for instance EP-A-372,628. Such lubricants use acetic acid to solubilise the diamines. However a problem here is that at low pH, lubrication is lost. The inventors have found that on replacing acetic acid with a quaternary ammonium compound, and in particular didecyl dimethyl ammonium chloride, an effective lubricant is provided. It has further been found that in comparison to lubricants of the prior art, the level of diamine compounds in the lubricant composition can be reduced without substantially effecting activity, whereby a low-foaminf lubricant, which can be easily washed away, is provided. Definition of the invention According to a first aspect of the present invention, there is provided a lubricant concentrate composition according to claim 1, which can be diluted to a lubricant composi¬ tion. According to a second aspect of the invention, there is provided a method of lubricating a system such as a bottle washing or a conveyor belt system, comprising the steps of diluting the lubricant concentrate composition of the invention and passing the resulting diluted lubricant through the system. According to a third aspect, there is provided a lubricant composition obtainable by diluting the lubricant concentrate composition of the present invention, with water to a suitable use concentration. Preferably, the diluted lubricant composition is a 0.2 - 0.4% by weight aqueous solution of the lubricant concentrate composition of the invention. According to a fourth aspect, the present invention provides the use of a lubricant composition of the invention for lubricating a bottle washing system or a conveyor belt system. Detailed description of the invention Since the need to add a relatively large amount of acid to solubilise the diamines is obviated in lubricant compositions according to the present invention, substantially all the diamine becomes available for lubrication. Since, in comparison with known lubricants, the lubricants according to the present invention are more alkaline, they therefore yield protection against acidic spillages. A problem which may occur when using known lubricants in slat conveyor systems, is the occurrence of bio-films, which grow and colonize the systems, especially when such systems are shut down for example at the weekends. These bio-films, caused by water-born organisms, are the main cause of slimes, unpleasant smells and hygiene pro¬ blems associated with these types of systems. A further advantage of the lubricant compositions according to the present invention is that they overcome this problem of the formation of bio-films by providing an effective biocidal activity, whereby bio-organisms are prevented from growing in the system, and any such organisms already in the system are killed. The lubricant concentrate composition of the invention preferably comprises from 1 to 5% by weight of each diamine compound present therein. More preferably, the concentration of each diamine compound is in the range of from 1 to 2% by weight. The diamine compounds present in the lubricant composition of the invention are preferably selected from the group consisting essentially of N-oleyl-1, 3-diaminopropane and N- coco-1,3-diaminopropane, these giving effective results. The concentration of the quaternary ammonium compound present in the lubricant concentrate composition is preferably in the range from 4 to 10% by weight, more preferably from 5 to 6% by weight. The quaternary ammonium compound preferably has the general formula R 2 R 3 - N - R Cl " R 4 wherein R and R 2 = Cl - C5 and R 3 and R 4 = C8 - C12. and is most preferably didecyl dimethyl ammonium chloride. Furthermore didecyl dimethyl ammonium chloride offers the following advantages: - the pH range over which both lubricity and disinfec¬ tion (biocidal activity) are achieved when applying this quaternary ammonium compound in the composition of the invention, is wider than that achieved with known lubricants of the prior art -such as those disclosed by EP-A-372, 628, the upper pH limit being about 10 according to the present invention; - the sensitivity to anions in dilution water is sub¬ stantially reduced with respect to known lubricants, in other words the inventors have found a considerable improvement in the field of lubricants based on diamines, which are known to be susceptible to precipitation from use solutions containing high levels of anions, especially sulphates; - The chemical oxygen demand and nitrogen levels of the compositions according to the present invention containing this type of quaternary ammonium compound are reduced whereby environmental loading and effluent treatment costs are reduced, - The foam level with respect to known lubricants is substantially reduced, whereby the foam can be readily rinsed away and the lubricants compositions according to the present invention are cost effective. The lubricant composition of the invention preferably further comprises an acid, desirably acetic acid. The concentration of said acid in the concentrate composition is effectively in the range of from 0.01 to 1% by weight. In order to improve the detergency of the lubricant composition of the invention, said composition preferably further comprises a nonionic agent, the concentration of which being effectively in the range of from 0.1 to 5% by weight based on the concentrate composition. Said nonionic agent is preferably oleylamine ethoxylate. A further optional and preferred component of the lubricant composition is a detergent builder, which is preferably triethanolamine . The concentration of said builder preferably lies in the range of from 0.1 to 5% by weight based on the concentrate composition. The present invention is illustrated by way of the following example, in which % is by weight unless otherwise indicated. A lubricant concentrate was formulated having the following composition: %wt N-oleyl-l, 3-diaminopropane 1.5 N-coco-1, 3-diaminopropane 1.5 Acetic acid (60%) (other acids) 0.5 Didecyl dimethyl ammonium chloride (80%) 6.8 Water to 100.0 This concentrate composition was diluted with water to a 0.3 wt% dilute lubricant composition. It will be realised that the extent of dilution required for obtaining a suitable dilute lubricant composition is dependent on the concentration of the diamines in the concentrate composition.

Claims: CLAIMS 1. Lubricant concentrate composition, comprising one or more diamine compounds and one or more quaternary ammonium compounds, or soluble salts thereof. 2. Composition according to claim 1, wherein the diamine compounds are selected from the group consisting essentially of N-oleyl-l, 3-diaminopropane and N-coco- 1, 3-diaminopropane. 3. Composition according to claim 1 or 2, comprising from 1 to 5 wt% of each diamine compound present therein. 4. Composition according to any of the preceding claims wherein the quaternary ammonium compound has the gene¬ ral formula R, , N R λ + Cl ' wherein R 1 and R 2 = Cl - C5 and R 3 and R 4 = C8 - C12 5. Composition according to claim 4, wherein the quaternary ammonium compound is didecyl dimethyl ammonium chloride. 6. Composition according to any of the preceding claims, comprising from 4 to 10 wt .% of the quaternary ammonium compound. 7. Composition according to any of the preceding claims, further comprising acetic acid. 8. Composition according to claim 7, wherein the concentration of the acid lies in the range of from 0.01 to 1% by weight. 9. Composition according to any of the preceding claims, further comprising a non-ionic agent. 10. Composition according to claim 9, wherein the non¬ ionic agent is oleylamine ethoxylate. 11. Composition according to claim 9 or 10, wherein the non-ionic agent lies in the range of from 0.1 to 5% by weight . 12. Composition according to any of the preceding claims, further comprising a detergent builder. 13. Composition according to claim 12, wherein the detergent builder is triethanolamine. 14. Composition according to claim 12 or 13, wherein the concentration detergent builder lies in the range of from 0.1 to 5% by weight . 15. Method of lubricating a system, such as a bottle washing or a conveyor belt system, comprising the steps of diluting a lubricant concentrate composition according to claims 1-14, and passing the resulting diluted lubricant through the system. 16. Lubricant composition, obtainable by diluting the concentrate composition according to any of claims 1- 14 with water to a suitable use concentration.

Inventors: OFFILER MICHAEL THOMAS, VERBIEST WILLEM P, OFFILER, MICHAEL, THOMAS, VERBIEST, WILLEM, P.
Applicants: UNILEVER NV, UNILEVER PLC, UNILEVER N.V.
Application year: 1997
Main classification: C10M173
IPC codes: C10M173, C10N40