Lubricant compositions for power transmitting fluids

Abstract

An additive composition may comprise at least one phosphorus- and boron-containing dispersant, at least one boron-containing dispersant, and at least one detergent. Such composition may be useful in power transmissions to provide improved anti-shudder performance and/or improved friction durability.

1 . An additive composition comprising: 
 (a) at least one first phosphorus- and boron-containing dispersant in an amount of about 20 wt % or more in the additive composition;    (b) at least one second boron-containing dispersant, free of phosphorus; and    (c) at least one detergent.    
     
     
         2 . The additive composition of  claim 1 , wherein the first dispersant comprises a phosphorylated and boronated polyisobutylene succinimide, bis-succinimide, or mixture thereof.  
     
     
         3 . The additive composition of  claim 2 , wherein the polyisobutylene has a molecular weight of about 900 amu.  
     
     
         4 . The additive composition of  claim 1 , wherein the second dispersant comprises a boronated polyisobutylene succinimide, bis-succinimide, or mixture thereof.  
     
     
         5 . The additive composition of  claim 4 , wherein the polyisobutylene has a molecular weight of about 900 amu to about 1300 amu.  
     
     
         6 . The additive composition of  claim 1 , wherein the detergent comprises an overbased detergent.  
     
     
         7 . The additive composition of  claim 1 , wherein the detergent comprises a sulfonate or a phenate.  
     
     
         8 . The additive composition of  claim 1 , wherein the detergent comprises one or more of calcium sulfonate, magnesium sulfonate, sodium sulfonate, calcium phenate, and zinc phenate.  
     
     
         9 . The additive composition of  claim 1 , wherein the detergent comprises a calcium sulfonate having about 1.5 wt % to about 20 wt % calcium.  
     
     
         10 . The additive composition of  claim 1 , wherein the calcium sulfonate comprises a TBN of about 250 mgKOH/g to about 450 mgKOH/g.  
     
     
         11 . The additive composition of  claim 1 , wherein the detergent comprises a calcium phenate having about 2.5 wt % to about 8.5 wt % calcium.  
     
     
         12 . The additive composition of  claim 1 , wherein the detergent comprise a calcium phenate having a TBN of about 50 mgKOH/g to about 300 mgKOH/g.  
     
     
         13 . The additive composition of  claim 1 , further comprising one or more of an antioxidant, an extreme pressure additive, a corrosion inhibitor, an antiwear additive, a metal deactivator, an antifoam agent, a viscosity index improver, a pour point depressant, an air entrainment additive, a metallic detergent, and a seal swell agent.  
     
     
         14 . The additive composition of  claim 1 , wherein the additive composition is suitable for use in a transmission employing one or more of a slipping torque converter, a lock-up torque converter, a starting clutch and one or more shifting clutches.  
     
     
         15 . The additive composition of  claim 14 , wherein the additive composition is suitable for use in a belt, chain, or disk-type continuously variable transmission.  
     
     
         16 . A power transmitting fluid, comprising: 
 (a) a major amount of a base oil; and    (b) an additive composition comprising 
 (i) at least one first phosphorus- and boron-containing dispersant in an amount of about 2.0 wt % or more in the fluid;  
 (ii) at least one second boron-containing dispersant, free of phosphorus; and  
 (iii) at least one detergent.  
   
     
     
         17 . The power transmitting fluid of  claim 16 , wherein the first dispersant comprises a phosphorylated and boronated polyisobutylene succinimide, bis-succinimide, or mixture thereof.  
     
     
         18 . The power transmitting fluid of  claim 17 , wherein the polyisobutylene has a molecular weight of about 900 amu.  
     
     
         19 . The power transmitting fluid of  claim 16 , wherein the second dispersant comprises a boronated polyisobutylene succinimide, bis-succinimide, or mixture thereof.  
     
     
         20 . The power transmitting fluid of  claim 19 , wherein the polyisobutylene has a molecular weight of about 900 amu to about 1300 amu.  
     
     
         21 . The power transmitting fluid of  claim 16 , wherein the detergent comprises an overbased detergent.  
     
     
         22 . The power transmitting fluid of  claim 16 , wherein the detergent comprises a sulfonate or a phenate.  
     
     
         23 . The power transmitting fluid of  claim 16 , wherein the detergent comprises one or more of calcium sulfonate, magnesium sulfonate, sodium sulfonate, calcium phenate, and zinc phenate.  
     
     
         24 . The power transmitting fluid of  claim 16 , wherein the detergent comprises a calcium sulfonate having about 1.5 wt % to about 20 wt % calcium.  
     
     
         25 . The power transmitting fluid of  claim 16 , wherein the calcium sulfonate comprises a TBN of about 250 mgKOH/g to about 400 mgKOH/g.  
     
     
         26 . The power transmitting fluid of  claim 16 , wherein the detergent comprises a calcium phenate having about 2.5 wt % to about 8.5 wt % calcium.  
     
     
         27 . The power transmitting fluid of  claim 16 , wherein the detergent comprise a calcium phenate having a TBN of about 50 mgKOH/g to about 300 mgKOH/g.  
     
     
         28 . The power transmitting fluid of  claim 16 , further comprising one or more of an antioxidant, an extreme pressure additive, a corrosion inhibitor, an antiwear additive, a metal deactivator, an antifoam agent, a viscosity index improver, a pour point depressant, an air entrainment additive, a metallic detergent, and a seal swell agent.  
     
     
         29 . The power transmitting fluid of  claim 16 , wherein the additive composition is suitable for use in a transmission employing one or more of a slipping torque converter, a lock-up torque converter, a starting clutch and one or more shifting clutches.  
     
     
         30 . The power transmitting fluid of  claim 29 , wherein the additive composition is suitable for use in a belt, chain, or disk-type continuously variable transmission.  
     
     
         31 . A continuously variable transmission fluid comprising 
 (a) a major amount of a base oil; and    (b) an additive composition comprising 
 (i) at least one first phosphorus- and boron-containing dispersant in an amount of about 2.0 wt % or more in the fluid;  
 (ii) at least one second boron-containing dispersant, free of phosphorus; and  
 (iii) at least one detergent.  
   
     
     
         32 . A method of increasing steel-on-steel friction comprising: 
 lubricating a transmission having steel-on-steel friction with a lubricating composition comprising a major amount of a base oil and an additive composition comprising: 
 (a) at least one first phosphorus- and boron-containing dispersant in an amount of about 2.0 wt % or more in the fluid;  
 (b) at least one second boron-containing dispersant, free of phosphorus; and  
 (c) at least one detergent.  
   
     
     
         33 . A method of improving anti-shudder comprising: 
 lubricating a transmission having shudder with a lubricating composition comprising a major amount of a base oil and an additive composition comprising: 
 (a) at least one first phosphorus- and boron-containing dispersant in an amount of about 2.0 wt % or more in the fluid;  
 (b) at least one second boron-containing dispersant, free of phosphorus; and  
 (c) at least one detergent.  
   
     
     
         34 . A method of stabilizing steel-on-paper friction comprising: 
 lubricating a transmission having steel-on-paper friction with a lubricating composition comprising a major amount of a base oil and an additive composition comprising: 
 (a) at least one first phosphorus- and boron-containing dispersant in an amount of about 2.0 wt % or more in the fluid;  
 (b) at least one second boron-containing dispersant, free of phosphorus; and  
 (c) at least one detergent.