FOOD GRADE COMPRESSOR LUBRICANT

Fecha de publicación: 08/01/2016
Fuente: WIPO Food Portada
FOOD GRADE COMPRESSOR LUBRICAN"TBACKGROI_L"JD OF "I"HE I&:VEN?"ION(0630B] Thc equipinent used in tile food processing industry varies by scgrnc1:twith thc leading scgmer:ts co;nprising meat and poultry, beverages, snack foods,veget:lbles. aimd dairy. Vi"l~ile the equipment varies from segment to segmcnt, themoving parts such as bearings. gears, and slide i~lechaiiisilts are siniilar al~do Aer,require lubrication. The lubricants niost oftcil used include kydraulic. refrigeration,co~nprcssora nd gear oils, as wcll as all-purpose grcases. These foocl inclustry oilsnust nicet more s trillgcnt standards than other il~dustry1 ubricallts.1001121 Duc to the i~ilportance of ensuring and ~naintaining safeguards andstandards of quality for hod 13rod~lc"tst, he ti,c;c7 il~dttstrym ust colzmply with the r ~ ~ l e sand regulatio~ls set forth ilry the United States I>epartmelit of Agriculture (USDA).The Focd Safcry Inspcclion Service {FSIS) of the GSDA is respnnsiblc fcr ailprograms invol\iing the inspectiorm, grading, a;ld standf~rdization of meat, poultry:eggs. dairy products, fruits, and vegetables, These programs arc mandatory, andinspection of ison-hod cornpuu~ldsu scd in federally inspected pian~sis required.[0003] The PSIS is cussodian of thc official list of autllorizcd conlpounds for usein federally inspected plants. Tl-re official list (see page 11 -1, List of ProprietarySubstances am1 Non-food C o i n p ~ u ~ d>X~i,sc ellaneous I)ilblication Nurnber 14 i 9(1989) by the Food Safety and Inspection Service, United States Department ofAgriculture) states that lubricants asad other substarlces rliat arc susceptible toincidental food contact are considered indirect food additives under USDArcgulatious. Therefore. these lubricants, classified as either Ti- I or H-2, are requiredto be approved by the USDA beforc being used in food processislg plants. "The moststringent classification, H-I, is for !\ibricants approved for incidental fi3od contact.Tlze H-2 classification. is for uses whcre there is no possibility of food contact,assures that lio known poisons or carcii~ogens are used in the lubricant. Onee~nbodinlcnto f the present invention pertains to an W-l approveci lubricatir~go il.Tlre terms "H-l approved oil" and "food grade" will be used interchatlgeably for thepurpose of this application.IOOCB4) Although the USDA is no longer approving new jngrcdicnts andco~npositions, the W-l classificatior~ is still recognized by the world food industry.NSF is ilour listing and approving the food grade classification.]OB?tB§I In adclition to lnecting the recpirel~le~ltsfo r safety set by fedcralregulatory agencies, the product must he an effective lubricant. t.,ubricating oils forfood processing plants should Ifibricate lrxachine parts, resist viscosity change, resistoxidation, protect against rusting and corrosion, provide wear protection, prevcntfoaming and resist the formation of sludge while in service. Thc product should alsopcrforin eft"ectivcly at various Lubrication regimes ranging from hydrodynamic thicktilm regimes to boundary thin fiim reginles,100061 The oxidation, thermal, and hydrolytic stability characteristics of alubricating oil help predic~ how effectively an oil will maintain its lubricatingproperties over time and resisi. sludge formation. Hydrocarbon oils are partially~xidizcd whc~l conta~ted xith oxygeil at elevated temperatures fbl- prola:~gedperiods of timc. The oxidation process proci~lcesa cidic bodies witilirl the iubricati~igoil. ?"hese acidic bodies are corrosive t ~~,s ziaiso ftcr~p rese~ii il food processingequiprnci~t, and, .when ir: contact with both the oil and the air, are effectiveoxidation catalysts that furtl~er increase tlzc rate of oxidatio:~. Oxidation productscontribute to the forsnation of sludges that can clog valves, plug Glters, and resrxlt inovcrall breakdown of the viscosity characteristics of the lubricant. Under sotnccircumsta~~cessl,u dge formatior1 can result in pluggage, complcte loss of oil systeuiflow, and &ilure or damage to ~nachinery.[0007] Tlie ther~nal and hydrolytic stability characteristics of lubricating oilreflect primarily oil the stability of the lubricating bast: oil properties and the oiladditive package. The stability criteria mollitor sludge foni~ation,v iscosity change.acidity change, and the corrosior~ ter-tdeucics of the oil. 1-lydrolytic stability assessesthese clzaracteristics in the presence of water, Inferior stability characteristics resultin lubricating oil that loses lubricating properties over time and precipitates sludge.[0008] Altltougli such lubricants have been clesignect to be non-toxic as a foodsource contami~~ath~e~irt ,l ubricating properties are often less effective colnpared toco11s7eiltional lilbricants e.g., lirbricanrs having ingredients not approved for directfood contact. The lubrication industry has, to some degree, overcome this problemby incorporating specialty additives into the 1ubric:jnt compositions. For example,the iilclusion of performance additives has bee11 used to enhance antiwearproperties, oxidation inhibition, rust/corrosion inhibition, metal passivation,extreme pressure, friction modificatjor;. foam inhibition, and lubricity. Suc11chemistries are described in the following patents: U.S. Pat. No. 5,538,654 (Lawate,et al.); 1i.S. Pat. Tcro. 4,062,785 (Xibbert); U.S. Pat. No, 4,838,727 (McAninch); U.S.Pat. No. 5,338,471 aid U.S. IPat. Xo. 5,413,725 ( h i ) .J0009J A drawback to the food-grade-lubricants described in the above patentsrelates to oxidation resistance, pour point characteristics, liliiited formulatingcapability for viscosity breadth, and limited viscosity protection. The lubricantsoftsr~ have poor rheology characteristics when subjected to prolonged heat andmecl~anical stress.[B)0101] "Therelore, there rcrnains a need for a food-grade-lubricant that exhibitsexcelZent hydrolytic stahili ty, corsosior; resi~tancc, and mti-wedr. with s~bs/3ntia/i~nprc~vcmenitns oxidation resistance, pour point, viscosity index, viscosity breadthformulating capability. alld viscosity stability urhe;~ subjected to fhe therl~lai 2nd~nzchariicais tresses.SUMMARY Of"~~-EjNVEXrr"I0N[OCBld] The invcntiosi relates to an irnprvved food-grade-lubricaat useful ashydraulic oil, circulating oil, drip oil, general purpose oil, grease base oil, cable oil,chain oil. spindle oil, gear oil, and cornpressor oil for equipment in the food scrviceindustry. Specifically, it rzlates to a colnpositioil cornyrisiiig at least onepolyalphaolefin base fluid, at least one food grade poiyolester base fluid, atici atleast one food grade perfornlance additive.[0012] Thc invention provides corngositions that contain more than 5 percent byweight of a polyolcstcr base fluid. The inventjo~; provides co~npositions whereincomponent (c) comlxises (i) one or illore food grade antioxidants a~idior( ii) one ormore food grade metal passivators, wherein the slletal passivators may comprise oneor Inore food grade metal deactivators and/or oiie or more food grade corrosio~lir~hibitors. The invcntioil also pri!vides co~npositions that contain more tl~arl 5percent by weight of a polyolester base fluid and nrherein component (c) coxnprisesthe co~~ibinatioonf (i) one or more food grade antioxidants and (ii) one or morefood grade metal deactivators and (iii) one or more food grade corrosio~in hibitors.[OOII3] The irlventioil further provides coinpositions that also contain at least onefood grade oil comprising a~ least oue of the following: a synthetic ester, a whitepetraleuni oil, and a severely hydrotreated petrolcum oil,[h)(B14"J The iiivenrion also provides a method for preparing a food-gradelubricantcompositioll comprising the steps ot": a) providing at least onepolyalpha~lefiib~a se fluid; b) providing at least one polyolcstcr base fluid: c)providing at least one performance additive; and, d) blending the components ioform the composition.[00151 The ir~ventioia~ls o providzs a neth hod for lubricating a food industrymechanical device, the neth hod colnprising the steps of": lubricatir~gt he device witha co~llposition coxliprising: (a) at least one poiyaipiiaoIefin base fluid: (b) at Ieasrone polyolester base fluid; and (c) ai least one perfon~~ancaded itive.{0016{ Tile rnvei~tiorr prclcidcs improved fc)c?d-grade-lubl-lcarits thl-ough ihzcombir-iacion of" pclyalphaoIe,G~;s aild H-1 foodgrade polyolesters, pariicularly ivl~enthe improved lubricaats also contail1 a combination of 011e i;r more food gradea~ltioxidantsa nd one or nlorc faod grade inetai deactitators. The comi~oaitionsc anprovide euhanccd oxiilatioll rcsistance. pour. point characteristics, and viscositiesand are particularly useful ss hydraulic oil, circ~ilatingo il, drip oil, general purposeoil, grease base oil, cablc oil, chain oil. spindle oil, gear oil, and compressor oil forequipment in the food service industry.I>ErI"AIL,ET) P)ESCKIP?"[OI OF THE INVEIV_TLOJ[(BOI7j Various features and e1nbodimet;ts of the inventiox? will be describedbelow by way of non-limiting iilusiration.jO0II81 I3y "fbod grade" it is irieant a coniposition or lubricaat that meets thecriteria set forth by thc United States Food and Drug Ad~~iir~istratifoonr foodsadditives and/or lubricants with incidental food contact, for exanlple, as set out in21 C.F.R. 178.3570 (2007), thc contents of which are incorporated herein byreference, and/or which meet the criteria to achieve an "HI" ciassitlcation fromNSF International or all equivalent rating or classificatiorl From a counterpartstandards setting body..T--h-.e- .P oLt("g&~llaolrfiijz3 gse FIz~i"d10029) The foocl-grade-iubricant compositions of the prttsent inventioil compriseat least one polyalphsolefin, Polyalphaolcfii~s are snade by combining two or morealpha olefin molecules into 313 oligomer, or short-chain-length polymer. PAOs areall-hydrocarbon structures, and they contain 110 sulfur; pliosphorus, or metals.Because they are wax-free, they have low pour points, usually below -403C.Viscosity grades range from 3 to 100 cSt at 10OaC, and viscosity indexes for all burthe lowest grades exceed 140, PAOs have good thermal stability, but they requiresuitsbie antioxidant additives to resist oxidation. It is cornlllon to the il~dustryth atPAOs have limited ability to dissolve some additives and tend to shrink seals. Ithas been found that both probie~ns are overcome by formulating with a polyolesterbase fluid and also using a food grade al~tioxidant aiidior food gradc metaldeactivator.[ Benzer~epropanoic acid, 3,5-bis(l,l -dimethylethyl)-4-hydroxy-,th iodi-2, I -ethancdiyf ester, available cornlnercialiy from Ciba SpecialtyChemical Company.100491 Tlit: antioxidants may be present in tl~ec oniposition from 0.0 I % to 6.0%or from 0.02%. 0.03?/0, 0.05%. 0.1% to 6{Y/b, 4%. 3%- 1% or even 0.50/;,, Thcadditive niay be present in the composi!ion at 196, O.5?6, or less. These variousranges are typically applied tu all of the antioxida~zts present iiz ihc overallcomposition. Howcver ill some e~nbodirnents these ranges may also be applied toindividual antioxidants, so long as tile food grade iimitatious are take11 into account.[OD401 "The metal passivators suitablc for use in thc present itwention are notoverly limited ar-id may include both inctal deactivators and corsosioli inhibitors.1-iowever in some embodin~cntst he additives must be food grade aiid must nor beused in an amount that wo~lldre mo17et he food grade classification from the additiveand/or the resulting cotnpositiom.100411 Stiitable ix~etald eaciivators include tria~oleso r substituted triazoies. Forcsalnpie. ~olyItsiaiol~o:r talus-izzole inay be utilized iil the preserit invn-rtiou.Suitable exa~ilpleso f food grade rnetal deactivator i:~cIudeo r~co r niore of(ij One or morc: tolu-triazoies, for example 5.X-Bis(2-cthyl11exyi)-armcthyl-11-1-be;l~oiriazolei- - melhana~i~ine,C AS ~eglstratioi~n umber94270-86-711, sold co~nrnercialIy by Ciba-Geigy uildcr the trade l?a:ilcXrgarnet 39;(ii) One or mdre fatty aciils derived fro111 ar~i~nanl d/or vegetable sources,andlor the I~ydrogenated fornls of such fatty acids, for example Neo-FatprRQw hich is commercially available from Akzo Novel Chenlicals,Ltd..100421 Suitable food grade corrosioil inliibitors include one or more of:(i) N-Methyl-K-(1-0x0-9- octadecel~yl)glyciae, CAS registration nurnbcr1 1 0...2"?---8 - >(ii) Phosphoric acid. mono- and diisooctyl esters, rcacted with rerf-alkyl and((2 i 2-C 14) pri~narya ~nilles,C AS registration number 68 187--67-7;(iii) Dodecanoic Acid;(iv) Triphen yl phosphoro thionate, CA S registration 11umbe-r 597-8245 and(v) IPhosphoric acid, mono- and dihexyl esters, compounds withtetraniethylnotlylan~inesa nd C 1 1-1 4 alkylalnines.10043) 111 one embodimelzt, the metal passivator is coiz~prised of a corrosionadditive and a metal deactivator wlzercin the corrosion inhibitor and the metaldeactivator are hod grade and comply tvjth FDA rcgulaticns. One useful additiveis the N-acyl derivative of sarcosine, such as an K-acyl derivative of sarcosine,One example is ?I-methyl-l\;-(l-oxo-9-octadeceng~l~ylc)i r~e. "This dcrivative isavailable fkoin Ciba-Geigy under tile trade ilaine SARKOSULTbI 0. Anotheradditive is an imidazoline such as Aminc OT" ccommerciaiiy availabltt li-om C"iba-Geigy.[I10441 The metal passivators may be present in the colnpositioli from 0.01 0io to6.0% or fro111 0.02%, 0.03%. i).OS%, 0.1 % to 6%, 4%. 2"%, I O/o or even 6.5%. "I"headditive may be preseiit in the composition at 0.05% or less. Thcse various rangesare typically applied to all of the metal pnssivator additives present in the overallcomposition. XTowever in SOillc e~~~bodilnertthtess e ranges n~ayal so be applied toindividui-rl corrosion ir~kibi?or-asi ldi"or inetal deactivators, so 70ng as the f~oigl radcli~nitatictns arc taker1 into account. The ranges above may also be applied to ibccolxbiried total of ,211 z~rrosioni ~~hibiforsm, etal dcsctiv;-lturs and antioxidantsprescnt in the overall composiiion.{OO-llSj The compositions described herein may also include one or moreadditiolnal pcsformalice additives. Suitable additives inciude antiwear inhibitors,rust/corrosion inhibitors andlor metal deactivators (other than tl-iosc describedabove), pour point depressants, viscosity i~nprovers, tackifiers, cxtrerne pressure(EP) additives, friction ~nocliflers,f oam inhibitors, e~"i~uIsifiearns~d deixulsifiers.(00461 To prevent wear on the metal surface, the ~reseilti nventiol~u tilizes ananti-wear inhibitoriEP additirre and friction modifier. Anti-wear inhibitors, EPadditives, and friction ~nodifiers are available off tlze shelf from a variety ofveltdors and manufacturers. Sonie of these additives can perforni inore than one taskand any may bc utilized in tile present invention, as long as they are food grade.One food grade product that can provide anti-wear, EP, reduced friction andcorrosion inbibifion is phosphorus ailline salt such as Irgalube 349, which isco11lrnerciaZly available from Ciba-Geigy. Another food gradc anti-tveariEI"inhibitor/friction modifier is a phosphorus c o ~ ~ ~ p o uslu~cihi as is triphenyiphosphothianate (TPY"T), which is cornrnerciaIIy available from Ciba-Geigy underthe trade name Irgalube TPPT. The anti-wear inhibitors, EP, and friction rnodiiiersare typically about 0.1% to about 4% of the co~xpositiorzt and may be usedseparately or iri combination.[us471 In some elllbodirnents tlne composition further includes an additive fromthe group comprising: viscosity modifiers-ilicluding, but ~iot limited to. etliylcncvinyl acetate, polybatcncs, polyisobutylencs, poiymetitacrylates. oleiin copolyxners,esters of styrene malcic anhyciride copoly~~lersh,y drogenated styrei~e-dienecopolymers, hydrogenated radial polyisopretle, alkylated polystyrene, fui-rled silicas,and complex csters; and food gradc tackifieers like natural rubber solubilizeil in fooilgrade oils.f0048j The addition of a food grade viscosity modifier, thickeller, and/ortackifier provides atli\esikeiless and improves tiic viscosity and viscosity index ofthe Iubl-icani. Some applications and environmental conditions may require anadditioi-ial tacky s~lrf5cefi ir1-1 that protects equipment A-orn cu;rosior~a iid wear. Jathis embodimer;t. Ihc viscosity modifier., tl;ickener/tackifier is about i to about 20wcight percclit ~f the lubricant. Howcver, the viccosi ty rnodifi er, thickcneritackj fi ercan be from about 0.5 lo about 30 weight percent. A11 example of a fcod grademilreriai tllac can bc used in this invention is Functional V-584 a Fatural Iiubberviscosity ~nodifier/tackificr, which is available from Functio1;al Products, Inc.,Macedonia, Ohio. Another example is a complex ester C(i 5000 that is also amulcif~inctionsl product, viscosity modifier. pour poilit depressant, and frictio~imodifier tkoln Inolcx Chemical Co, Philadciphia, Pa.I00491 Other food gradc oils andlor conlponei~ts may be alsd added to thecori~position in the range of about 0.1 to about 30%. Tllese food grade oils couldinclude white petroleum oils, synthetic esters (as described in patent U.S. Pat. No.6,534,454). severely hydro-treated petroleu~n oil (known in the industry as "GTOLIPI1 or III petroleurll oils").hdcids&ihJ Application[0058] In some embodin~ents each of the composition ingredients of" thecomposition described herein 11ave H-1 approval as required by the United StatesISepartinent of Agriculture. It is ur~derstood that the H-l designatio~wi ill ultiinatclyrelatc to a comparable classif>cation in countries outside the United States in mostcases.[0051] The col-npositions described herein may be prepared by bleildirlg thevarious compolients tcgett~er. "The means of blcnding and/or order of addition is notoverly limited.IU052j Altllough the colnpositiol~o f the present invention is particillarly usefulas a lubricant in the food servicc inciustry, it is not limited to applications thatrequire (Sirect food contact. For exan~plc, thc u~iiclue coinbination of propertiesallows the inventive lubricant to be used in any application wherein a continuousand efficient reduction in friction is required. Examples may include engine oil,hydraulic tluid, grease, ctc.{0053] The foed-grade-lubrirsal~t compositions dcscrihed above can be uscd Inall types of food processing equip~nclitJ0054I In some e~nbodirrlents the compositions of the present invcntiox are: (i)fion: 5 or !O to 40 o: 25% focd grade i;olyc?i cster base fluid, (lij from 7G or 79 to83 or 90"36 polyalpl~aolefin base fluid, (iiij fic~ln 0.05, 0.5, 1.0 or 2.0 to 2.4%a;lfioxidantss. (iv) from 0.01, or 0.95 to 0.1 or (2.07 ;~-,erald eacti\citors andlorcorrvsion ini~ibit~rosr, jv) any cor~~binatiothne reof".-E-X A--M. PLESBe3055j "[he invention will be f~~rtheilrlu strated by the f~llowiilge xamples,which sets forth particularly adval~tageous embodiments. While the examples arepro\~ideci to illustrate the present illvention, they are not intended to limit it. Unlessotiierwisc nored, each of the additives and additive packages described below maycontail1 scrne amount of clil~rent oil or similar inaterial.Examz>le-llI00561 A food grade lubricant is prepared by blencling a polyalphaolefin basefluid, PAO-6 with an antioxidant additive package and a metal yassivator package.The additive package contains (i) N-phcnyl-ar-(l,1,3,3-tetramethylbuty1)-lnaphthalenan2ine7(ii) N-phenylbenzerlamine reaction products with 3,4,4-trimethylpentene, and (iii) 1 "6-hexamethylei1ebis(3,5-di-tert-butyl-4-I~ydro~yllydrc~~i~~nanw?haetree ),t he antioxidants arc present in the package atweight ratios of 2.5:2.5:1 respectively. The metal passivator package contains Neo-FatTh$, a fatty acid corrosion inhibitor, and Irg;i~xt.t~3" 9, a benzotriazole rnetaldeactivator, in a wcight ratio of 2.S:l respectively.{06)57] The resulting blend contains O?/O food grade poiyolester, 98.7%polyalphaolefil~. 2.2% of the arltioxidailt additive package, and 0.07% of the metalpassivator package. The resulting blend has a kinematic viscosity at 40"47 of 32cst.Exa~nplc2 .100581 A food grade luhrica~~ist preparecl by blending a food grade polyojesterbase fluid and a blcnd of two polyalpl~aolefin base fluids, I"AO-8 and PAO-6 wherethe weight ratio of the polyalpl~aolefinb ase fluids in the blcnd is 1.2:l respectively.An anric\xidant additive packagc is acldcd to the blel~d. The antioxiclant packagecontains equal parts on a weigh1 basis of (i) X-phenyl-ar-(I , I ,3,3-letrat?lethylE?~1tj~- rlL -naphthaiena~ninc, (iij bis(4-j I. i ,3.7-tetramcthyibutyljphenyl) aminc, (iii) Kphenylbenze~ial~inree action products with 2,4,4- triixethylpentene, (iv) 1,6-. . hexarnethy l,erze0~~(3,5-di-tert-bui,vl-4-hydiwxyl1ydroci1~i?aamnadt e)(,v ) benzenepropanoicacid. 3 ,S-bis( i , i - dimeth yl ethyl)-4-llydroxy--, thiodi-2, l -ethar?.ediyl cs ter.100591 "The resulting blend conidills 1096 food g r ~ d epa lyolester, 87.5% of thepolyalphaolefin blend and 2.5% ofthc ailtioxidant additive package (such that eachantioxidant is present at 0,50%). The resulting blend has a kineinatic viscosity at40°C of 39 cS1.-E-x amale 3.[B)CB$O] A food grade lilbricaat is prepared by blelldirlg a food gradc polyclesterbase fluid and a blol~do f two polyalphaolefil~b ase fluids, PAO-8 and PAO-G whorethe weight ratio of tl~ep oIyalpl~aoleGnb ase fluids in the blend is 3.3 1 respectively.The antioxidant additive package ciescribed in Conlparativc Exaniple 2 is added tothe blcncf. A metal passivator additive package is also added to thc blend. Themetal passivator packagc contains hso-FatTM, a fatty acid corrosior~i ~hibiior,a ndIrganietThl -39, a benzotriazole metal deactivator, in a weight ratio of 2.5:Irespectively.{006B] The resulting blend contains 25% food grade poiyolester. 72.43% of tilepalyalyhaolefin blend, 2.5% of the antioxidant additive package (such that eachantioxidant is present at 0.50%) and 0.07% of the rnetal actjvator additive package."The resulting blend has a kinematic viscvsjly at 40°C of 46 cSt.Exam~2le4 . --p ---[6)062] A food grade lubricant is preparzd following the procedures of Exanlple3. The resulting blend contains 25% food grade polyolesfer, 72.43% of thepolyalphaoiefin ble~id,2 ,50/;, of the antiosida~~atd ditive package (such that eachantioxidant is present at 0.50%) and 0.07(% of the metal activator additive package."She resulling blend lias a kineriiatic viscosity at 40°C of 39 cSt.100631 Each of the cxamsples is tested in a hot room caliipressor test. Thej~~volvessu pply each test lubricant to a variable speed drive rotary screwcolnprcssvr operating at 110°C (230°F) and 100 psia. Sarnples of the liubricant aretake11 every 160 ilows of cotnprcssor operatiorr time and analyzed to evaluate theperfor~llttnceo f the lubricant. Each saxnplz is analyzed to determine the total acidnuillber (TAS) of the lubrieai~t.a s rncasurcd by AS"I"M D974. A higher is anindication tbat a lribricant is losi~~itgs effectiveness, 14 lubricant is gel~crallyccnsidered to be past its usable service live when its TAN exceeds a value of 2.0 oreve11 1.0. Thc longer the period of operation time where a lubricant"s :"AN is below2.0 or ever\ 1.0, thc loi~gert he I~brjcarit"ss ervicc life and the betrer the lubricant"sperformance.IOO64_J The results of testing co~npletedis sunSystem.Environment.newlinelanz.ed i r t~h e tablc below:"I"a"ole 1 - Summary of Elst Roidrn Compresssr Results2 77;F~A : ",in/i:p3i~ t c"st erzn"etr" crftpr. ijie 21104 hou, ~ n n l p iJO~T" ?*c.itj A . ~ C! ?iic~!biji ~ " ~ l ) a tolff E ; . r ~ ~ i ~3 ~rlj?~rrite sh ow_\h ow the r ~ , ~ t l ro\Jf E J ~ o Y ~3 ~;VIOEcII C! haverouize o ~ fhcr ci lhtrt fes! bee,? cble r o rliii to ro~i?j1/efer107?faci865j The results show that ihi: compclsitions of the prescut I~rt,ention pri?videsigiliiican~ly irnprovcd lubricant perfiormar~cc as dcrnonstrated by the extendcduseable qervice livc (titnc of use befbre thc TAX of Ihc lul~ricanr exceeds 1 .O) ofExamples 2 and 3 arid -1 colnpareci to kxampIe I . Example L shows that tile use of"antioxidailts and lnetal passivators in a PAO-based lubricant Jocs not perf"clrm well(the sample excccds a TAK of I .O before 2733 hours of tcsting arid exceed a TANof 2.0 hzfore 2303 hours of testing). Exainple ?I shows that a blend of PA0 and afood grade polyol ester. with an additional additive package can pcrforin better thanExa~i~pl1e. E"urtl~ermoreE xample 3 shows that a blend of PA0 and food gradepotyol ester in combination wit11 a food grade additive package that colnbiilesantioxidants and metal passivators provides a significant i~nprove~liellti npcrfirnnance coinpared to Example 1, and ever] co~nl?aredto Example 2. Example4, tvl~icfiis prepared using the same procedure and amounts of nlalcriaIs as Example3. also sl~ows this significant ilnprovement, compared to Example I, ard evencoinpared to Exa~nplc 2 (the sanlple exceeds a TAN of 1.0 after 4854 l.lours oftesting and exceed a TAX of 2.0 bcforc 5386 hours of testing). The results alsoshow that Examples 3 and 4 had very similar perforinance up until rlie test for-- - 1 2 - 9 - I 1.31 / 2303-.-1.. ?f*-10 I a 2399 1 -- 1.56 2378 j 19.602 5 6,T I T O P P E D + I 3850 -. 0.4-5-- .-- -..-2739 -- 3.24i 2811 4.00s T Q p p i ~ - - jI jii i I[Ji 1/1j I1 1 4516 1 0.71 ii1ri "5 294 5386---- :::: 1-.-.. Ji . .- .-.. -.-.------ .----.- TEST sTopqenI TAW : ~ z / ua~rtsz r rtei1.c i.lrerl pct ASTM R974.I . .-4680 i; -.-- 0.74 1I 4854 1 1.L4 " , -51861.23 - --.---i; 1.71 " 5219 1.67Example 3 had to be discontinued. At about 2000 hours of run time, Examples 3and 4 both had TAN values of about 0.4.[Ob)6b) The perfonnarice of the lubricants inay be evaluated by comparing thear~iounto f test lime that passes until tile "TAN of the lrrbricnirt cxcceds 1 .O. In someernbodinicnts the lubricants may be evaluated by comparing the amount of test timethat passes until the TAN of the lubricant exceeds 2.0,I00671 Each of 111e doc urn cat^ referred to above is incorporated herein byrei"creizce. Except in the Exalnples, or where otherwise explicitly indicated, allnumerical quantities in this description spccifying amounts of materials, reactionconditions, molecular weights, nurnber of carbon atoims, and the like, are to beunderstcjod as ~l~odiiiebdy rlze word "about." "linless othenvise indicated, allpcrcclnt values, ppm values and parts values are on a weight basis. Unlessotherwise ir~dicatcd. each cllelnical or compositioil rcfcrred to herein should beinterpreted os being a commercial gratfe iliuferial which may corltain the ison?ers,by-proc?ucts, derivatives, arid othcr s~lctl?~~ aterir,/ws hich are noranlly ~~~?dersttcoo dbc prcsent in the co~~~iner"cgiaral dr, Howc-vcr, the arnoul~t of sack cl3cmicalco~~lpofienist prcscntcd excll-,si:.e of ariy solvent or dilusnt oil, which rriay becustoinarily presen: ili the co~~llnercimaia terial, urlless otherwise indicated. X t is tobe uild~rstoodt hat the upper and lower a~~zouir~ant.g e, and ratio li~nitss et forthherein may he independently cortlbined. Sinlilarly. the ranges and al~zounts for eachclcnient of the invention can bc used togcther with ranges or anlour~tsf or any of theother eIcr~~cntsA. s used lzereir~.t bc expression "consisting esserltially of" pernlitsthe incl~lsioilo f substa~~ctehsa t do not ixaterially affect the basic allti novel cbaracterisficsof the compositioi~u nder cor~sicieration.Wc claim:1. A food grade l~bricanct o~llpositionc omprising:(a) at least one polyalphaolefi~b~a se fluid:(bj at least one food grade polyolester base fluid; and(c) at least one food grade performalice additive.2. Tile composition of claim 1 wherein tlze compositioi~i s more than 5 perceiltby weight polyolestcr base fluid.3. ?"he composition of clairri I wlzerein component (c) coinprises thecoinbillation of" (i) onc or more food grade antioxidants and (ii) one or more foodgrade metal passivators, u~i~ercitnh e metai passivator may co~nprise a metaldeactivator, a corrosion inhibitor, or combinations thereof.4. "T"he ccmposition of claim 1 wllerei~l the composition has id kinei~laticviscosity ~??;OI3T0I :Q 320 GS! at 40°C.5. Tl~cco ~llposisiono f clni;n i wllcrcin:coi~~poi~el(:at ) is present from at Ic::st I pcrclcnt by weight:comgoae~zt (b) is preser~t r"r-orn ai least 5 percelli by weight: andcol.;Iponent (cj is present from 0.01 to 6 percent by weight.6, ?"he co~~~positioofn c laim 1 ivherein coi~ponent( a) has a nun~bcra veragemolectriar weight of 425 to 2500.7. The composition of claim 1 wllereill cumpoi~ent (a), the polyalpl~aolefin basefluid, col~lprjses PA02, P,403, PA06, PA08, PAO10, PA040, PA01 00 ormixtures thcreof.8. The composition of claim 1 whereill compone~~(bt ), the polyolester basefluid base fluid, comprises: esters of neopenty l glycol, glycerol, trirnef hyIolpropai~e, pentaerythritol, dipentaerythritoi, tripentaerythritd, casboxylic acidsrepresented hy tile formula HOC(O)R", where R" is a saturated, cyclic, straightchain or branched hydrocarbon radical containing from 4 to 10 carbon atoms, orcombinations thercof,9. "Tile composition of claim 1 wherein component (c) comprises at least oneadditiol~nl additive selected fr-oin the List consisting of antioxidants, metaldeactivators. corrnsioil ii~hibitors, antifoams, antiwear inhibitors, corrosioninhibitors, pour point depressants, viscosity improvers. tackifiers, nietaldeac~i~atorse,x trcnlc pressure additives, friction modifiers, lubricity additives,foam inhibitors. e;nulsificrs, demulsifiers, or tl~ixturesth ereof.10. The composition of cIai111 3 wherein component (c)(i), the antioxidant,corrlyrises one or more aminic antioxidants, phcnolic antioxidants, or combinationsthercoi": whereir; conlpoiient (c)(i) is present in thc ovcrail composition from 0,01 lo6 percent by weight.I I , Thc composition of ciai~r!3 wherein compol~eni(,c f(ii), &lie1 11etal passivator,comprises o~ieor 111orc toiytriazole dcrivcd metal deactivators, fatly acids corrosioninhibitors derived fi-olli naturai oils, or combinations thcrcof; whereir; cornpollel~i(c)(ii) is prescnt in tile overall composition from 0.02 to 0.05 perccct by weight.1 . The co~nposition of clairn I whereill the composition further comprises atleast one food grade oil comprising at least one of the follo~vil~ga :s yntlzetie ester, awhite petroleum oil, a11cI a sevcrely hydro-treated petroleulri oil.13. A rncthod for preparing 3 food-gradc-lubrica~~cto inpositic>n comprising thesteps of: a) providing at least one polyaJphaolcfin base fluid; b) providing at leastone polyoiester base iluid: c) providing at least one performance adclitive; and, d)blei~dingth e components to form tl~eco mposition.14, A method for l~~bricati~a lgfo od industry nlechanicai device, the methodcomprisi~.lgth e steps of: lubricating the device with a conlposition comprising: (a)at least one polyalphaolefin base fluid; (b) at least one polyolester base fluid; and(c) at least one perforinailce additive.15. The method oi" clajln 14, wherein tile co~~lpositiofunr ther comprises at leastone food grade oil comprising at least one of the following: a synthetic ester, awhite petroleunl oil, and a severely hydro-treated petroleum oil.,ii.>>