DESC:FORM 2

THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003

COMPLETE SPECIFICATION
[See section 10, Rule 13]

Title of invention:

LUBRICANT FOR ALUMINIUM

Applicant:

HINDALCO INDUSTRIES LIMITED, an Indian Company, having its address at 21st Floor, One International Center, Tower 4, Prabhadevi, Near Prabhadevi Railway Station, Senapati Bapat Marg, Mumbai 400013, Maharashtra, India.

Preamble to the description:

The following specification particularly describes the invention and the manner in which it is to be performed.

FIELD OF THE INVENTION
[001] The present invention relates to a lubricant composition for drawing aluminium and its alloys. The present invention further relates to a process for preparing the lubricant composition.

BACKGROUND OF THE INVENTION
[002] Aluminium drawing is a process that forms metal work stock by reducing its cross section. This is accomplished by forcing the work through a mold (die), of smaller cross-sectional area than the work. The primary purpose of drawing is to achieve a desired shape, size, or mechanical property in the metal, often with improved dimensional accuracy and surface finish. Drawing is commonly used in the production of wires, tubes, and other components.
[003] The drawing process is usually performed cold. Cold working imparts the drawn product with accurate tolerances, favorable grain structure, improved material properties, and good surface finish. Drawing technology provides effective manufacturing solutions for producing seamless products including cans, foils, kitchen utensils, window frames, beer kegs, gas cylinders, and aero-plane parts, automotive parts, etc.
[004] Lubrication is an important factor, and its application can help control the forces and metal flow. Effective lubrication also extends the life of the mold, reduces temperature, and improves surface finish.
[005] Lubrication can be applied for both wet and dry drawing techniques. In wet drawing, the dies and the work are completely submerged in lubrication. Whereas in dry drawing, lubrication is applied to the material by use of a stuffing box containing lubricant located in front of the mold. Work passes through the box and picks up lubrication before entering the mold. A drawdown equipment works on the dry drawing principle.
[006] Due to inadequate lubrication, the quality of the product is not appropriate, but in fact poor. Moreover, the product also lacks the desired shape and finish. Furthermore, normal aluminum drawing lubricants are inappropriate for all drawing equipments as they are liable to cause defects such as scoring marks and poor surface finish. In view thereof, specialized lubricants have been developed in the state-of-the-art which provide sufficient lubrication, heat removal, along with good product quality in terms of surface finish and productivity.
[007] For instance, US20110287993A1 discloses an oil composition for minimal quantity lubrication aluminium processing. The composition has been used as a lubricant for bearing portions, hydraulic devices, and gear portions. Specifically disclosed for this purpose are naphthenic mineral oils (75 mass%), polyolesters, solid lubricants such as boron nitride, oiliness improver such as polyoxyalkylene compounds having alkylene groups such as butylene (ethylethylene) groups, extreme pressure additive such as phosphoric acid esters, etc.
[008] CN104560297 discloses a lubricant oil composition for hybrid or electric vehicle comprising lube base oil (preferably 50 mass % or more), polyol ester as an antirust agent, viscosity modifier as polyisobutene, additives such as phosphorus acid esters (phosphite ester) or their amine salts as anti-wear additive, thiadiazole compounds.
[009] Despite the available state-of-the-art, there is still a need to provide a specialized lubricant for aluminium drawing which provides lesser wear and tear, and improves the ease of handling, without compromising the product quality in terms of surface finish and productivity.
[010] Thus, there is a need in the art for a lubricant composition for drawing aluminum and its alloys, which addresses at least the aforementioned problems.

SUMMARY OF THE INVENTION
[011] In one aspect, the present invention is directed to a lubricant composition for drawing aluminium and its alloys comprising: a base oil in a range of 60 wt.% – 70 wt.% of the total lubricant composition; an ester in a range of 1 wt.% – 15 wt.% of the total lubricant composition; boron nitride in a range of 5 wt.% – 25 wt.% of the total lubricant composition; and an additive in a range of 5 wt.% – 25 wt.% of the total lubricant composition.
[012] In an embodiment, the base oil is an API Group V base oil. The base oil is selected from a hydro treated naphthenic base oil, polyalkylene glycol, and phosphate ester.
[013] In another embodiment, the ester is a polyol ester having a kinematic viscosity at 40°C ranging between 30000 cSt to 60000 cSt determined according to ASTM D445.
[014] In still another embodiment, boron nitride has a mean particle size ranging between 5 µm to 15 µm.
[015] In yet another embodiment, the additive is selected from a viscosity improver, an anti-wear additive, and an extreme pressure additive.
[016] In still another embodiment, the viscosity improver is selected from polymethacrylate, polyisobutylene, polyisoprene, and olefin copolymers.
[017] In another embodiment, the anti-wear additive is an amine-neutralized phosphoric acid ester.
[018] In a further embodiment, the extreme pressure additive is selected from at least one of hydrocarbon, white mineral oil (petroleum), amines, coco alkyl dimethyl, N-oxides, oxidation inhibitor, detergent, alcohol, and mixtures thereof.
[019] In still further embodiment, the additive comprises: (i) viscosity improver in a range of 5 wt.% – 10 wt.% of the total lubricant composition, (ii) extreme pressure additive in a range of 1 wt.% – 5 wt.% of the total lubricant composition, and (iii) anti-wear additive in a range of 1 wt.% – 4 wt.% of the total lubricant composition.
[020] In another aspect, the present invention is directed to a process of preparing the above lubricant composition. The process comprises mixing the base oil, ester, boron nitride, and additives.
[021] In another embodiment, the mixing is carried out at a temperature ranging between 50oC to 70oC.

DETAILED DESCRIPTION OF THE INVENTION
[022] Before the compositions and formulations of the present invention are described, it is to be understood that this invention is not limited to particular compositions and formulations described, since such compositions and formulations may, of course, vary. It is also to be understood that the terminology used herein is not intended to be limiting since the scope of the present invention will be limited only by the appended claims.
[023] The terms “comprising”, “comprises” and “comprised of” as used herein are synonymous with “including”, “includes” or “containing”, “contains”, and are inclusive or open-ended and do not exclude additional, non-recited members, elements or method steps. It will be appreciated that the terms “comprising”, “comprises” and “comprised of” as used herein comprise the terms “consisting of”, “consists” and “consists of”.
[024] Furthermore, the terms “first”, “second”, “third” or “(a)”, “(b)”, “(c)”, “(d)” etc. and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are capable of operation in other sequences than described or illustrated herein. In case the terms “first”, “second”, “third” or “(A)”, “(B)” and “(C)” or “(a)”, “(b)”, “(c)”, “(d)”, “i”, “ii” etc. relate to steps of a method or use or assay there is no time or time interval coherence between the steps, that is, the steps may be carried out simultaneously or there may be time intervals of seconds, minutes, hours, days, weeks, months or even years between such steps unless otherwise indicated in the application as set forth herein above or below.
[025] In the following passages, different aspects of the present invention are defined in more detail. Each aspect so defined may be combined with any other aspect or aspects unless clearly indicated to the contrary. In particular, any feature indicated as being preferred or advantageous may be combined with any other feature or features indicated as being preferred or advantageous.
[026] Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment but may. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner, as would be apparent to a person skilled in the art from this disclosure, in one or more embodiments. Furthermore, while some embodiments described herein include some, but not other features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the invention and form different embodiments, as would be understood by those in the art. For example, in the appended claims, any of the claimed embodiments can be used in any combination.
[027] Furthermore, the ranges defined throughout the specification include the end values as well, i.e., a range of 1 to 10 implies that both 1 and 10 are included in the range. For the avoidance of doubt, the applicant(s) shall be entitled to any equivalents according to applicable law.
[028] In the present context, “drawing” refers to the process of reducing cross-sectional dimensions of a metal workpiece, herein aluminum and its alloy, by pulling it through a die, said die imparting a specified shape to the metal workpiece. The drawing operation may be conducted under dry or wet conditions, with dry drawing involving the absence of a lubricant, and wet drawing involving the use of liquid lubricants and coolants to reduce friction and dissipate heat during the drawing process. The drawing operation is typically carried out within a temperature range of approximately 150°C to 350°C, where the specified temperature range optimizes the plastic deformation of the metal workpiece while maintaining desired mechanical properties. The drawn metal workpiece may include wires, rods, or tubes, and the drawing operation aims to achieve improved mechanical properties, dimensional accuracy, and surface finish.
[029] As used herein, the term "olefin" refers to a hydrocarbon containing at least one carbon-carbon double bond. Further, the term “copolymer”, unless otherwise indicated, includes terpolymers, tetrapolymers, etc., of ethylene, said C3 to C28 alpha-olefin and/or a non-conjugated diolefin or mixtures of such diolefins which may also be used. The amount of the non-conjugated diolefin will generally range from about 0.5 to about 20 mole percent based on the total amount of ethylene and alpha-olefin present.
[030] Further, API Group base oil described herein refers to the classification system for different types of base oils developed by API (American Petroleum Institute). The classification is based on the refining processes used to produce the base oils and their properties. The API categorizes base oils into five groups, with Group I being the least refined and Group V being the most highly refined. The API Group V includes all other base oils that specifically do not fall into Groups I to IV.
[031] An aspect of the present invention relates to a lubricant composition for drawing aluminium and its alloys.
[032] In an embodiment, the lubricant composition comprises: a base oil in a range of 60 wt.% – 70 wt.% of the total lubricant composition; an ester in a range of 1 wt.% – 15 wt.% of the total lubricant composition; boron nitride in a range of 5 wt.% – 25 wt.% of the total lubricant composition; and an additive in a range of 5 wt.% – 25 wt.% of the total lubricant composition.
[033] The base oil aids in dissolving high additive loads, has good solvent power, metal affinity, cooling properties, and low temperature properties. The base oil is thus, preferably, an API Group V base oil. In an embodiment, the base oil is selected from a hydro treated naphthenic base oil, polyalkylene glycol, and phosphate ester. Preferably, the base oil is hydro treated naphthenic base oil. In another embodiment, the hydro treated naphthenic base oil has one or more of the following properties: kinematic viscosity at 40°C ranging between 20 cSt to 30 cSt determined according to ASTM D445, flash point (Pensky-Martens Closed Cup (PMCC)) ranging between 170°C to 190°C determined according to ASTM D93A, density at 20°C ranging between 0.85 g/ml to 0.95 g/ml determined according to ASTM D4052, acidity of less than 0.01 mg KOH/g determined according to ASTM D974, and pour point ranging between -55°C to -35°C determined according to IS 1448:Part 10.
[034] In an embodiment, the base oil is present in the composition in an amount ranging between 62 wt.% to 67 wt.% of the total lubricant composition. Commercially available base oil, such as those available from NYNAS, may also be used in the present invention. More preferably, the base oil is NYNAS T 22.
[035] Esters provide good solvency and variant temperature performance (high and low). Suitable ester is, preferably, a high viscosity saturated polyol ester. The polyol ester of the present invention has one or more of the following properties: kinematic viscosity at 40°C ranging between 30000 cSt to 60000 cSt determined according to ASTM D445, flash point (Pensky-Martens Closed Cup (PMCC)) of more than 300°C determined according to ASTM D93A, density at 20°C ranging between 0.90 g/ml to 0.95 g/ml determined according to ASTM D2596, acidity ranging between 0.009 mg KOH/g to 0.02 mg KOH/g determined according to ASTM D974, and pour point ranging between 1°C to 10°C determined according to IS 1448:Part 10.
[036] Commercially available polyol esters, such as those available under the trade name PriolubeTM may also be used in the present invention. More preferably, the polyol ester is Priolube 3986.
[037] In an embodiment, suitable amount of the polyol ester ranges between 5 wt.% to 10 wt.% of the total lubricant composition.
[038] Boron nitride in the lubricant composition shows characteristic lubrication properties with respect to aluminum and its alloys. Boron nitride minimizes surface defects on profiles and increases productivity.
[039] In an embodiment, the boron nitride is 325 Tyler mesh hexagonal boron nitride having a mean particle size ranging between 5 µm to 15 µm. A discussion of hexagonal boron nitride can be found, for example, in Kirk-Othmer, Encyclopedia of Chemical Technology, Fourth Edition, Vol. 4, pp. 427-429, John Wiley and Sons, New York, 1992. Preferably, the particle size ranges between 7 µm to 11 µm. Moreover, the amount of boron nitride in the composition is preferably in the range of 10 wt.% to 20 wt.% of the total composition.
[040] In another embodiment, the additive is selected from a viscosity improver, an anti-wear additive, and an extreme pressure additive. Preferably, the additive comprises: (i) viscosity improver in a range of 5 wt.% – 10 wt.% of the total lubricant composition, (ii) extreme pressure additive in a range of 1 wt.% – 5 wt.% of the total lubricant composition, and (iii) anti-wear additive in a range of 1 wt.% – 4 wt.% of the total lubricant composition.
[041] In one embodiment, the viscosity improver is selected from polymethacrylate, polyisobutylene, and olefin copolymers.
[042] Typically, the polymethacrylate viscosity improvers (VI) employed in the present invention are polymeric methacrylates containing short, intermediate, and long-chain hydrocarbon side chains. Short-chain hydrocarbon side chains typically have from about 1 to about 7 carbon atoms. For example, both methyl and butyl (either n-butyl, isobutyl, or mixtures of the two) methacrylates have been used. Methyl methacrylate is the most common. Intermediate-chain hydrocarbon side chains typically contain from about 8 to about 15 carbon atoms and may be derived from alcohols including 2-ethylhexyl alcohol, isodecyl alcohol and alcohol mixtures which may be, for example, C8 to C10, C12 to C14 or C12 to C15 alcohol mixtures. Long-chain hydrocarbon side chains generally will contain about 14 or more carbon atoms and may be based, for example, on C16 to C18 or C16 to C20 alcohol mixtures. Further, the polymethacrylate VI improvers may be any type of non-dispersant type or dispersant type polymethacrylate compounds which are used as VI improvers for a lubricating oil.
[043] Olefin copolymers (OCPs) employable in the present invention include copolymers of two or more olefins such as ethylene, propylene, butylene, iso-butylene, isoprene, butadiene and the like, as well as copolymers of these olefins with other monomers such as styrene, cyclopentadiene, dicyclopentadiene, ethylidene-norbornene and so on. Exemplary OCPs for the purpose of the present invention relate to ethylene copolymers. Oil soluble ethylene copolymers used in the invention generally will have a number-average molecular weight (Mn) of from above 5,000 to 500,000. Polymers having a Mw/Mn of less than 10 are most desirable. As used herein, (Mn) and (Mw) are measured by the well-known techniques of vapor phase osmometry (VPO), membrane osmometry and gel permeation chromatography. In general, polymers having a narrow range of molecular weight may be obtained by a choice of synthesis conditions such as choice of principal catalyst and cocatalyst combination, addition of hydrogen during the synthesis, etc. Post synthesis treatment such as extrusion at elevated temperature and under high shear through small orifices, mastication under elevated temperatures, thermal degradation, fractional precipitation from solution, etc. may also be used to obtain narrow ranges of desired molecular weights and to break down higher molecular weight polymer to different molecular weight grades for VI use.
[044] Preferably, the viscosity improver is polyisobutylene or PIB.
[045] Commercially available viscosity improvers, such as those available under the tradename Indopol®, may also be used in the present invention. Preferably, the viscosity improver is Indopol® H 300. PIB Indopol® H 300 has little or no odor, resistance to oxidation, wear resistance, and good tensile strength. It is also stable, has inert characteristics and high spreadability.
[046] In another embodiment, the extreme pressure additive is selected from at least one of hydrocarbon, white mineral oil (petroleum), amines, coco alkyl dimethyl, N-oxides, oxidation inhibitor, detergent, alcohol, and mixtures thereof.
[047] Commercially available extreme pressure additives, such as those available from PolytronTM, may also be used in the present invention. For instance, PolytronTM MTC, which is a complementary oil additive package mixture of butene, white mineral oil (petroleum), amines, coco alkyl dimethyl, N-oxides, oxidation inhibitor and detergent, propan-2-ol, and ethanol may be used in the present invention. PolytronTM MTC has polarized hydrocarbons which are attracted to the metal surfaces where they permeate into the metal structure.
[048] In yet another embodiment, the anti-wear additive is selected from amine-neutralized phosphoric acid ester, zinc dithiophosphate (ZDP), zinc dialkyl dithiophosphate (ZDDP), Tricresyl phosphate (TCP), halocarbons, and fatty acid such as stearic acid. Preferably, the anti-wear additive is amine-neutralized phosphoric acid ester.
[049] Commercially available extreme pressure additives, such as those available under the tradename Additin®, may also be used in the present invention. Preferably, the extreme pressure additive is Additin® RC 3760, which contains 4.9% P, and 2.5% N. This additive is ashless and provides extreme pressure and also anticorrosion properties to the lubricant composition.
[050] Accordingly, in an embodiment, the lubricant composition comprises: the base oil in a range of 60 wt.% – 70 wt.% of the total lubricant composition; the ester in a range of 1 wt.% – 15 wt.% of the total lubricant composition; boron nitride in a range of 5 wt.% – 25 wt.% of the total lubricant composition; viscosity improver in a range of 5 wt.% – 10 wt.% of the total lubricant composition; extreme pressure additive in a range of 1 wt.% – 5 wt.% of the total lubricant composition, and anti-wear additive in a range of 1 wt.% – 4 wt.% of the total lubricant composition.
[051] In another embodiment, the lubricant composition consists of: the base oil in a range of 60 wt.% – 70 wt.% of the total lubricant composition; the ester in a range of 1 wt.% – 15 wt.% of the total lubricant composition; boron nitride in a range of 5 wt.% – 25 wt.% of the total lubricant composition; viscosity improver in a range of 5 wt.% – 10 wt.% of the total lubricant composition; extreme pressure additive in a range of 1 wt.% – 5 wt.% of the total lubricant composition, and anti-wear additive in a range of 1 wt.% – 4 wt.% of the total lubricant composition.
[052] Advantageously, the present invention provides a specialized lubricant for aluminium drawing which provides less wear and tear, and improves the ease of handling, without compromising the product quality in terms of surface finish and productivity.
[053] Another aspect of the present invention relates to a process of preparing the lubricant composition, as described hereinabove. Accordingly, the embodiments pertaining to the lubricant composition are applicable here as well.
[054] In an embodiment, the process comprises mixing the base oil, ester, boron nitride, and additive. Suitable mixing means are well known to the person skilled in the art and therefore, the present invention is not limited by the same.
[055] In another embodiment, the mixing is carried out at a temperature ranging between 50oC to 70oC.
[056] In yet another embodiment, the process comprises the following sequential steps: the base oil and the ester are mixed at temperature in the range of 50°C to 70°C with continuous stirring in a kettle for 30 minutes. After 10 minutes, the additives are added to the mixture of base oil and ester at temperature in the range of 50°C to 70°C and stirred for 10 minutes to 15 minutes to make a homogeneous mixture. Thereafter, boron nitride is added and stirred for 30 more minutes, followed by continuous stirring up to a minimum of 60 minutes to obtain a consistent composition.
[057] EXAMPLES
[058] The following examples are illustrative of the present invention but not limitative of the scope thereof:
[059] Compounds:
Base oil Nynas T22
(hydro treated naphthenic base oil having kinematic viscosity at 40°C ranging between 20 cSt to 25 cSt determined according to ASTM D445)
Ester Priolube 3986
(saturated polyol ester having kinematic viscosity at 40°C ranging between 40000 cSt to 50000 cSt determined according to ASTM D445)
ADDITIVE
Viscosity improver Indopol H300 (polyisobutylene)
Extreme pressure additive Polytron (EP)
Anti-wear additive Additin RC 3760
(amine-neutralized phosphoric acid ester)
[060] General synthesis of lubricant composition in accordance with the present invention:
[061] Various lubricant formulations (F1 to F5) were prepared wherein different amounts of the base oil and ester, in a kettle, were mixed at temperature in the range of 50°C to 70°C for 30 minutes to obtain a mixture. Different amounts of viscosity improver, extreme pressure additive, and anti-wear additives were added to the mixture at temperature in the range of 50°C to 70°C and stirred for 10 minutes to 15 minutes to make the mixture homogeneous. Further, different amounts of boron nitride were added to the homogenous mixtures and stirred for a minimum of 90 minutes. Table 1 below represents different lubricant formulations with specific weights of all the components:
[062] Table 1: Comparative and inventive examples
Component F1
wt.% F2
wt.% (Comparative) F3
wt.% F4
wt.% F5
wt.%
Base oil
65.2 65.2 62 66.2 65.2
Viscosity improver
6 6 9.2 5 6
Ester
9 9 9 9 9
Extreme pressure additive 1.8 4 3 3 3
Wear and tear additive 3 0.8
(below range) 1.8 1.8 1.8
Boron Nitride 15 15 15 15 15
Final Composition 100 100 100 100 100
[063] The aforementioned samples were tested for various properties. The results have been summarized in Table 2 below.
[064] Table 2:
Specific tests performed Test Method F1 F2
(Comparative) F3 F4 F5
Appearance In-house White colour White colour White colour White colour White colour
Kinematic Viscosity at 40 °C, (mm2/s) ASTM D445 224.3 215.2 250.5 205.1 220.1
Anti-Wear Test,
scar diameter in (micron)
by Four Ball Tester ASTM D4172 701 788 755 738 742
Coefficient of Friction Four Ball Tester 0.1503 0.1401 0.1419 0.1439 0.1428
EP Test - Pass load, (Kg)
by Four Ball Tester ASTM D2596 300 400 400 400 400
EP Test - Weld load, (Kg)
by Four Ball Tester ASTM D2596 400 500 500 500 500
Copper Corrosion IS1448:(P15) 1a 1a 1a 1a 1a
Aluminium Corrosion Aluminium sheet sample at 110 °C for 3 hours Normal Normal Normal Normal Normal
[065] It may be concluded from Table 2 that the lubricants (F1, F3 to F5), which were prepared in accordance with the present invention, show better lubricant properties. Whereas the comparative formulation (F2) showed a higher wear and tear scar diameter of 788 microns.
[066] Comparative compositions were prepared in accordance with the general synthesis, as above. In each of the comparative compositions listed in Table 3, the amounts of one or more ingredients of the lubricant composition were beyond the ranges of the present invention. These compositions were also tested for various parameters, the results of which are summarized in Table 4.
[067] Table 3: Comparative examples
Component F6 (wt.%) F7 (wt.%) F8 (wt.%)
Base Oil 55.2
(below range) 68.2
72.2
(beyond range)
Viscosity improver 16
(beyond range) 3
(below range) 6

Ester 9 9 9
Extreme pressure additive 3 3 3
Anti-wear additive 1.8 1.8 1.8
Boron Nitride 15 15 8
[068] Table 4:
Specific tests performed Test Method F6 F7 F8
Appearance In-house White colour White colour White colour
Kinematic Viscosity at 40 °C, (mm2/s) ASTM D445 256.5 175.3 193.6
Anti-Wear Test,
scar diameter in (micron)
by Four Ball Tester ASTM D4172 834 775 815
Coefficient of Friction Four Ball Tester 0.1624 0.159 0.1476
EP Test - Pass load, (Kg)
by Four Ball Tester ASTM D2596 300 400 400
EP Test - Weld load, (Kg)
by Four Ball Tester ASTM D2596 400 500 500
Copper Corrosion IS1448:(P15) 1a 1a 1a
Aluminium Corrosion Aluminium sheet sample at 110 °C for 3 hours Normal Normal Normal
[069] As noted from Table 4, higher amounts of viscosity improver and lower amounts of the base oil (refer F6), resulted in a higher lubricant viscosity as well as wear properties which rendered it difficult to use in the drawing application. Furthermore, higher amounts of the base oil (refer F8) and lower amounts of the viscosity improver (refer F7) also resulted in insufficient properties, at least in terms of wear and kinematic viscosity. Therefore, it can be concluded that the present invention lubricant composition not only results in acceptable wear properties and viscosity but is also a synergistic combination of the ingredients.
[070] Thus, the present invention provides a specialized lubricant for aluminium drawing which provides less wear and tear, and improves the ease of handling, without compromising the product quality in terms of surface finish and productivity.
[071] The foregoing description of the present invention has been set merely to illustrate the present invention and is not intended to be limiting. Since the modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to the person skilled in the art, the present invention should be construed to include everything within the scope of the disclosure.
[072] Further, it will be apparent to the person skilled in the art that various changes and modifications may be made without departing from the scope of the present invention as defined in the following claims.
,CLAIMS:WE CLAIM:
1. A lubricant composition for drawing aluminium and its alloys comprising:
- a base oil in a range of 60 wt.% – 70 wt.% of the total lubricant composition;
- an ester in a range of 1 wt.% – 15 wt.% of the total lubricant composition;
- boron nitride in a range of 5 wt.% – 25 wt.% of the total lubricant composition; and
- an additive in a range of 5 wt.% – 25 wt.% of the total lubricant composition

2. The lubricant composition as claimed in claim 1, wherein the base oil is an API Group V base oil.

3. The lubricant composition as claimed in claim 2, wherein the base oil is selected from a hydro treated naphthenic base oil, polyalkylene glycol, and phosphate ester.

4. The lubricant composition as claimed in claim 1, wherein the ester is a polyol ester having a kinematic viscosity at 40°C ranging between 30000 cSt to 60000 cSt determined according to ASTM D445.

5. The lubricant composition as claimed in claim 1, wherein the boron nitride has a mean particle size ranging between 5 µm to 15 µm.

6. The lubricant composition as claimed in claim 1, wherein the additive is selected from a viscosity improver, an anti-wear additive, and an extreme pressure additive.

7. The lubricant composition as claimed in claim 6, wherein the viscosity improver is selected from polymethacrylate, polyisobutylene, polyisoprene, and olefin copolymers.

8. The lubricant composition as claimed in claim 6, wherein the anti-wear additive is an amine-neutralized phosphoric acid ester.

9. The lubricant composition as claimed in claim 6, wherein the extreme pressure additive is selected from at least one of hydrocarbon, white mineral oil (petroleum), amines, coco alkyl dimethyl, N-oxides, oxidation inhibitor, detergent, alcohol, and mixtures thereof.

10. The lubricant composition as claimed in one or more of claims 1 to 9, wherein the additive comprises: (i) viscosity improver in a range of 5 wt.% – 10 wt.% of the total lubricant composition, (ii) extreme pressure additive in a range of 1 wt.% – 5 wt.% of the total lubricant composition, and (iii) anti-wear additive in a range of 1 wt.% – 4 wt.% of the total lubricant composition.

11. A process of preparing the lubricant composition as claimed in one or more of claims 1 to 10, the process comprising mixing the base oil, ester, boron nitride, and additive.

12. The process as claimed in claim 11, wherein the mixing is carried out at a temperature ranging between 50oC to 70oC.

Dated this 2nd day of January 2023
Hindalco Industries Limited
By their Agent & Attorney

(Nisha Austin)
of Khaitan & Co
Reg No IN/PA-1390