Lubricant composition for industrial gearing coming into contact with food

Abstract

The invention relates to a lubricant composition comprising: at least one base oil for coming into contact with food, selected from the groups II, III or V according to the categories defined in the API classification or the equivalents thereof according to the ATIEL classification; at least one hydrogenated polyisobutylene; and at least one ester polymer.

Claims

1. A lubricant composition comprising: from 20 to 50% by weight of at least one base oil for food contact, wherein said at least one base oil is a white oil; between 45 and 60% by weight of at least one hydrogenated polyisobutylene having a number average molar mass of between 400 and 1500; and at least 5% by weight and less than or equal to 10% by weight of at least one ester polymer selected from the group consisting of copolymers of alpha-olefin and α-β-ethylenically unsaturated dicarboxylic acid esterified with alcohols, said at least one ester polymer having an average molecular mass (Mw) of between 1500 and 2500, a viscosity at 100° C. determined according to ASTM D-445 of between 25 and 45 mm.sup.2/s, and a pour point determined according to ASTM D-97 between −10° C. and 0° C.; relative to the total weight of the lubricant composition; wherein the lubricant composition has a kinematic viscosity at 40° C. measured according to ISO 3104 between 500 and 2000 mm.sup.2/s.

2. The lubricant composition according to claim 1 having a pour point of less than −24° C.

3. A method of lubrication of gearing comprising placing the lubricating composition according to claim 1 into contact with the gearing being lubricated.

4. The lubricant composition according to claim 1 wherein the at least one ester polymer has a pour point between −8° C. and −0° C.

5. The lubricant composition according to claim 1 wherein the at least one ester polymer has a pour point between −8° C. and −2° C.

Description

COMPOUNDS IMPLEMENTED IN THE EXAMPLES

(1) TABLE-US-00002 Chemical Molar mass KV40 Pour point Component nature (Mn) (mm.sup.2/s) (° C.) Finavestan White oil 65.80 −12 A360B ® Finavestan A80B ® White oil 15.90 −9 Indopol H300 ® Hydrogenated 1300 4 polyisobutylene Ketjenlube 240 ® Polymer ester −6 Synesstic 5 ® Synthetic −33 base oil (naphthalene derivative) Indopol H25 ® Hydrogenated 635 −22 polyisobutylene Indopol H7 ® Hydrogenated 440 −34 polyisobutylene Lubrizol 3130A ® Hydrogenated 3 polyisobutylene Irgalube 232 ® Anti-wear phospho-sulfur antifoam mixture of antioxidants, anti- wear and anti- corrosion agents

(2) The molar mass Mn of the hydrogenated polyisobutadiene is measured by gel permeation chromatography (derived from ASTM D3536).

(3) The kinematic viscosity at 40° C. is measured according to ISO 3104.

(4) The viscosity index is measured according to the ISO 2909 standard.

(5) The pour point is measured according to ISO 3016.

Compositions

Comparative Compositions (White Oil+Hydrogenated Polyisobutadiene)

(6) TABLE-US-00003 CC1 CC2 CC3 FINAVESTAN A360B 63.8 56.4 50.5 INDOPOL H300 36.2 43.6 49.5 Kinematic viscosity at 40° C. 470.3 690.5 1005 (mm.sup.2/s) Viscosity index 112 115 116 Pour point (° C.) −18 −21 −21

(7) These lubricant compositions which only include the combination of food contact oil and PIB do not have the expected characteristics in terms of pour point and therefore in terms of resistance at low temperatures.

(8) TABLE-US-00004 FINAVESTAN A360B ® 36.6 27.3 INDOPOL H300 ® 51.2 50.5 KETJENLUBE 240 ® 5 10 SYNESSTIC 5 ® 5 10 Antioxidant and anticorrosive 1.5 1.5 mixtures IRGALUBE 232 ® 0.4 0.4 antifoam 0.3 0.3 TOTAL 100 100 Kinematic viscosity at 40° C. 994.4 1003 (mm.sup.2/s) Viscosity index 122 123 Pour point (° C.) −24 −30 FINAVESTAN A360B ® 46.5 46.5 45 45 FINAVESTAN A80B ® 46.5 INDOPOL H300 ® 48.5 48.5 INDOPOL H1200 ® INDOPOL H2100 ® LUBRIZOL 3130A ® 48.5 INDOPOL H25 ® 50 INDOPOL H7 ® 50 KETJENLUBE 240 ® 5 5 5 5 5 Pour point (° C.) −33 −24 −24 −27 −33

(9) These results show that the specific combination of the invention of a incidental food contact oil (excluding PAO) with a PIB and an ester polymer makes it possible to obtain a lubricant composition: meeting the criteria for incidental food contact; having a high viscosity; having a low pour point and therefore good performance at low or very low temperatures.

(10) In a particularly surprising manner, with respect to the compositions CC1, CC2 and CC3, the addition of a relatively high pour point ester polymer makes it possible to greatly reduce the final pour point of the lubricant composition and thus to improve its behavior at low, even very low temperatures.