Detergent and dispersant systems for improved steel piston cleaning in heavy-duty lubricants

Abstract

To provide a lubricant composition that satisfies new performance characteristics while maintaining conventional fluid performance. [Solution] This disclosure provides a crankcase lubricating oil composition, particularly a heavy-duty crankcase lubricating oil composition, that achieves high piston cleanliness of steel pistons according to the OM471 piston cleanliness test by using a sulfonate soap detergent system and a dispersant system of one or more polyisobutylene succinimide dispersants in the lubricating oil composition.

Description

[Technical Field]

[0001] This disclosure relates to a lubricating composition, and more specifically, to a heavy-duty lubricating composition that exhibits improved piston cleanliness when used with a steel piston and with a selected detergent system and dispersant system. [Background technology]

[0002] Automakers continue to demand improvements in efficiency, fluid life, and fuel economy, and as a result, the requirements for engines, lubricants, and their components are constantly increasing. These requirements also mean that the performance of engine oils must evolve to meet the higher demands of such modern engines and their corresponding performance standards associated with their unique uses and applications. Such stringent demands on engine oils often lead lubricant manufacturers to tailor lubricants and their additives to meet certain performance requirements for industrial and / or manufacturer applications. Typically, industry standards and / or automotive manufacturers require certain performance standards, meaning that a lubricant designed for one use or application may not necessarily meet all performance specifications for a different use or application.

[0003] For example, the selection of detergents and dispersants in engine oil formulations often involved only a few relevant considerations based on several factors, including but not limited to piston cleanliness, acid neutralization, TBN retention, oxidation, low-speed premature ignition, wear, friction performance, fuel economy, supply, and / or cost factors. However, it has been previously accepted that piston cleanliness in diesel engines typically requires the use of detergent sources other than sulfonates, and therefore diesel piston cleanliness generally required a combination of, for example, phenate and sulfonate detergents. These combinations tended to result in formulation drawbacks by limiting the selection of auxiliary components in the formulation and / or tended to cause formulation trade-offs that could affect overall performance.

[0004] Conventional heavy-duty engines (i.e., engines configured for vehicles with a gross vehicle weight of approximately 6,000 pounds or more) often use aluminum pistons, and conventional phenate and sulfonate cleaning agents have been effective in maintaining piston cleanliness in such engine configurations. Previously, piston cleanliness for specific applications was evaluated according to the OM501LA (CEC L-101-08) test using aluminum pistons. Recently, some heavy-duty engines, configured for vehicles with a gross vehicle weight of approximately 6,000 pounds or more, have generally shifted to the use of steel pistons, which allow for increased pressure and temperature within the cylinder, to help achieve improved fuel efficiency by having less friction, higher torque management, and / or long-term durability. However, with the upgraded engines and the shift to steel pistons, the industry has also developed more demanding piston cleanliness tests, designated as the OM471 piston cleanliness test of CEC L-118-21. This test uses an engine with a steel piston and configured to produce greater power and torque than the engine used in the OM501LA test. Designed for steel pistons, this new piston cleanliness test is not only more stringent than the OM501LA test in terms of pressure and temperature, but also twice as long (approximately 600 hours instead of approximately 300 hours), and / or at higher maximum power and torque levels. The OM471 test produces a significantly increased engine power of approximately 391 kW compared to the OM501LA test, which produces an engine power of approximately 358 kW.

[0005] Therefore, heavy-duty engine lubricants must now demonstrate passability when subjected to the more stringent operating conditions of the new OM471 test of CEC L-118-21. However, in many situations, altering the components within a lubricant composition to satisfy newer performance characteristics tends to adversely affect one or more other performance characteristics. Thus, it becomes difficult for lubricant manufacturers to meet newer industrial performance requirements while simultaneously maintaining conventional fluid performance. [Overview of the project]

[0006] In one approach or embodiment, the present disclosure relates to a method for lubricating a diesel engine, in particular a heavy-duty diesel engine having a steel piston. The present invention is particularly suitable for lubricating an engine having a steel piston, specifically a heavy-duty diesel engine having a steel piston. In one aspect, the method includes lubricating the steel piston of a diesel engine, in particular a heavy-duty diesel engine, with a lubricating oil composition. In another embodiment, the lubricating oil composition comprises (i) a detergent system comprising one or more alkaline earth metal sulfonate detergents that contribute up to about 1 weight percent of sulfonate soap (preferably about 0.3 to about 1 weight percent of sulfonate soap) to the lubricating oil composition, and (ii) a dispersant system comprising one or more polyisobutylene succinimide dispersants that contribute at least about 5 weight percent of one or more dispersants to the lubricating oil composition, wherein the one or more polyisobutylene succinimide dispersants have a number average molecular weight of about 1,200 to about 2,500 and are derived from highly reactive polyisobutylene that contribute more than 650 ppm of nitrogen to the lubricating oil composition. In some embodiments, diesel engines, particularly heavy-duty diesel engines, are operated under conditions as shown in the OM471 piston cleanliness test of CEC L-118-21, and in some embodiments, over engine powers of up to approximately 600 hours (or up to approximately 400 hours or approximately 400 to approximately 600 hours) and / or up to approximately 391 kW.In some embodiments, the lubricating oil composition further comprises an antioxidant system of one or more ashless antioxidants (preferably alkylated diphenylamine and hindered phenol) and a molybdenum-containing antioxidant, wherein the molybdenum-containing antioxidant comprises an oil-soluble molybdenum compound selected from the group consisting of molybdenum dithiocarbamate, molybdenum dialkyldithiophosphate, sulfur-free organic molybdenum complex of organic amide, or mixtures thereof, and the one or more ashless antioxidants are selected from hindered phenol, aromatic amine, alkylated diphenylamine, phenyl-α-naphthylamine, alkylated phenyl-α-naphthylamine, hindered non-aromatic amine, sulfurized olefin, or mixtures thereof, and in one embodiment, the lubricating composition contains at least about 2 weight percent, at least about 2.2 weight percent, or at least about 2.5 weight percent of the antioxidant system. One approach is for the antioxidant system to include at least 1.0 weight percent of diphenylamine, at least 1.0 weight percent of hindered phenol, and less than 0.2 weight percent of a molybdenum-containing compound in the lubricating composition.

[0007] In further approaches or embodiments, the method for lubricating a diesel engine having a steel piston, particularly a heavy-duty diesel engine, as described in the preceding paragraph, may include any combination of optional features, steps, or embodiments. These optional features, steps, or embodiments may include one or more of the following: the diesel engine, particularly a heavy-duty diesel engine, is configured to power a vehicle having a gross vehicle weight rating of about 6,000 pounds or more, and / or the cleaning system comprises one or more overbasic calcium sulfonate cleaning agents and one or more underbasic calcium sulfonate cleaning agents, wherein the overbasic cleaning agent has a total base number (TBN) of at least about 200 mg KOH / g, and the underbasic cleaning agent has a total base number (TBN) of about 175 mg KOH / g or less, and the total base number (TBN) is defined as ASTM Determined by D2896, and / or the cleaning agent system includes a weight ratio of one or more overbasic sulfonate cleaning agents to one or more lowbasic sulfonate cleaning agents in a ratio of approximately 3:1 to approximately 8:1 (in other embodiments, approximately 3:1 to approximately 6:1, approximately 3:1 to approximately 5:1, or approximately 3:1 to approximately 4:1), and / or the cleaning agent system includes a ratio of approximately 2:1 to approximately 4:1 (in other embodiments, approximately 2.1:1 to approximately 3.5:1, approximately 2.2:1 to approximately 3:1, or approximately 2.3:1 to approximately 2.The cleaning agent system comprises a weight ratio of overbasic sulfonate soap to low-basic sulfonate soap in an 8:1 ratio, and / or comprises one or more overbasic sulfonate cleaning agents in an effective amount to provide the cleaning agent system with at least about 5 mg KOH / g, and one or more low-basic sulfonate cleaning agents in an effective amount to provide about 25 to about 40 weight percent cleaning agent soap, and / or the cleaning agent system consists essentially of a calcium sulfonate cleaning agent, and / or the cleaning agent system is substantially free of magnesium sulfonate cleaning agents, substantially free of phenate cleaning agents, or a combination thereof, and / or the lubricating oil composition contains about 50 ppm to about 200 ppm of molybdenum provided by an oil-soluble molybdenum compound selected from the group consisting of molybdenum dithiocarbamate, molybdenum dialkyldithiophosphate, sulfur-free organic amide molybdenum complex, or mixtures thereof, and / or lubrication The oil composition further comprises about 0.5 to about 5 weight percent of one or more ashless antioxidants selected from hindered phenols, aromatic amines, alkylated diphenylamines, phenyl-α-naphthylamines, alkylated phenyl-α-naphthylamines, hindered non-aromatic amines, sulfurized olefins, or mixtures thereof, and / or the lubricating oil composition comprises up to about 1200 ppm of phosphorus from one or more metal dihydrocarbyl dithiophosphate compounds having hydrocarbyl groups derived from mixtures of linear or branched primary alcohols and linear or branched secondary alcohols, and / or the heavy-duty crankcase lubrication composition contains a negligible amount of magnesium, e.g., about 20 ppm or less or about 10 ppm or less.

[0008] In further other approaches or embodiments, the herein disclosure provides crankcase lubricant compositions, in particular heavy-duty crankcase lubricant compositions, suitable for diesel engines having a gross vehicle weight of about 6,000 pounds or more and equipped with steel pistons. In aspects of this embodiment, the crankcase lubricant composition, in particular heavy-duty crankcase lubricant composition, comprises one or more base oils of lubricating viscosity; a detergent system comprising one or more alkaline earth metal sulfonate detergents that impart up to about 1 weight percent of sulfonate soap (preferably about 0.3 to about 1 weight percent of sulfonate soap) to the lubricant composition; and a dispersant system comprising one or more polyisobutylene succinimide dispersants that impart at least about 5 weight percent of one or more dispersants to the lubricant composition, wherein the one or more polyisobutylene succinimide dispersants are derived from highly reactive polyisobutylene having a number average molecular weight of about 1,200 to about 2,500 and imparting more than 650 ppm of nitrogen to the lubricant composition. In some embodiments, diesel engines, particularly heavy-duty diesel engines, are operated under conditions as shown in the OM471 piston cleanliness test of CEC L-118-21, and in some embodiments, over engine powers of up to approximately 600 hours (or up to approximately 400 hours or approximately 400 to approximately 600 hours) and / or up to approximately 391 kW. In some embodiments, the lubricating oil composition achieves a steel piston cleanliness rating of at least 90% when measured by the OM471 piston cleanliness test (CEC L-118-21) (higher percentage ratings indicate cleaner pistons).In other embodiments, the crankcase lubricating oil composition, particularly the heavy-duty crankcase lubricating oil composition, further comprises an antioxidant system of one or more ashless antioxidants (preferably alkylated diphenylamine and hindered phenol) and a molybdenum-containing antioxidant, wherein the molybdenum-containing antioxidant comprises an oil-soluble molybdenum compound selected from the group consisting of molybdenum dithiocarbamate, molybdenum dialkyldithiophosphate, sulfur-free organic molybdenum complex of organic amide, or mixtures thereof, and the one or more ashless antioxidants are selected from hindered phenol, aromatic amine, alkylated diphenylamine, phenyl-α-naphthylamine, alkylated phenyl-α-naphthylamine, hindered non-aromatic amine, sulfurized olefin, or mixtures thereof, and in one embodiment, the lubricating composition contains at least about 2 weight percent, at least about 2.2 weight percent, or at least about 2.5 weight percent of the antioxidant system. One approach is for the antioxidant system to include at least 1.0 weight percent of diphenylamine, at least 1.0 weight percent of hindered phenol, and less than 0.2 weight percent of a molybdenum-containing compound in the lubricating composition.

[0009] In further approaches or embodiments, the crankcase lubricants described in the preceding paragraph, in particular, heavy-duty crankcase lubricants, may include any combination of optional features or embodiments. These optional features or embodiments may include one or more of the following: a detergent system comprising one or more overbasic calcium sulfonate detergents and one or more underbasic calcium sulfonate detergents, wherein the overbasic detergent has a total base number (TBN) of at least about 200 mg KOH / g, and the underbasic detergent has a total base number (TBN) of about 175 mg KOH / g or less, and the total base number (TBN) is defined as ASTM Determined by D2896 and / or the cleaning agent system comprises a weight ratio of one or more overbasic sulfonate cleaning agents to one or more low-basic sulfonate cleaning agents in a ratio of approximately 3:1 to approximately 8:1 (in other embodiments, approximately 3:1 to approximately 6:1, approximately 3:1 to approximately 5:1, or approximately 3:1 to approximately 4:1), and / or the cleaning agent system comprises a weight ratio of overbasic sulfonate soap to low-basic sulfonate soap in a ratio of approximately 2:1 to approximately 4:1 (in other embodiments, approximately 2.1:1 to approximately 3.5:1, approximately 2.2:1 to approximately 3:1, or approximately 2.3:1 to approximately 2.8:1), and / or the cleaning agent system contains at least approximately 5 mg The cleaning agent system comprises an effective amount of one or more overbasic sulfonate cleaning agents to provide KOH / g, and an effective amount of one or more low-basic sulfonate cleaning agents to provide about 25 to about 40 weight percent cleaning agent soap, and / or the cleaning agent system consists essentially of a calcium sulfonate cleaning agent, and / or the cleaning agent system is substantially free of a magnesium sulfonate cleaning agent, substantially free of a phenate cleaning agent, or a combination thereof, and / or the lubricating oil composition is molybdenum dithiocarbamate The lubricating oil composition contains approximately 50 ppm to approximately 200 ppm of molybdenum provided by an oil-soluble molybdenum compound selected from the group consisting of molybdenum dialkyldithiophosphate, sulfur-free organic amide molybdenum complexes, or mixtures thereof, and / or approximately 0.The lubricating oil composition further comprises 5 to approximately 5 weight percent of one or more ashless antioxidants, and / or contains up to approximately 1200 ppm of phosphorus from one or more metal dihydrocarbyl dithiophosphate compounds having hydrocarbyl groups derived from mixtures of linear or branched primary alcohols and linear or branched secondary alcohols, and / or the heavy-duty crankcase lubricating composition contains a negligible amount of magnesium, e.g., approximately 20 ppm or less, or approximately 10 ppm or less.

[0010] In further approaches or embodiments, the disclosure herein provides the use of any embodiment of the lubricating oil composition outlined in the present invention, particularly heavy-duty lubricating oil composition, to achieve improved steel piston cleanliness according to the OM471 piston cleanliness test (CEC L-118-21), or in other embodiments, to achieve a steel piston cleanliness character of at least about 90% as measured by the OM471 piston cleanliness test (CEC L-118-21). [Modes for carrying out the invention]

[0011] This disclosure relates in particular to a heavy-duty crankcase lubricant composition for lubricating a heavy-duty diesel engine having steel pistons, and a method of lubrication, effective in achieving piston cleanliness that passes the new OM471 piston cleanliness test of CEC L-118-21, which conforms to the ACEA E8 specification. In an approach or embodiment, the heavy-duty lubricant composition of this specification is suitable for achieving piston cleanliness that passes the OM471 test on steel pistons. Such heavy-duty diesel engines and the lubricants of this specification are configured to power vehicles having a gross vehicle weight rating of about 6,000 pounds or more. Such engines often have an engine capacity of 10 liters or more, steel pistons, a maximum output of about 600 horsepower, a maximum torque of about 1,900 ft-lbs, and / or an exhaust gas recirculation system. The present invention is particularly suitable for lubricating engines having steel pistons, and more specifically, for lubricating heavy-duty diesel engines having steel pistons.

[0012] In the approaches or embodiments herein, crankcase lubricant compositions suitable for such engines and vehicles, in particular heavy-duty crankcase lubricant compositions, preferably comprise at least (i) a detergent system comprising, or consisting of, or essentially comprising, one or more alkaline earth metal sulfonate detergents that contribute up to about 1 weight percent of sulfonate soap to the lubricant composition, and (ii) a dispersant system comprising one or more polyisobutylene succinimide dispersants that contribute at least about 5 weight percent of one or more dispersants to the lubricant composition. In other approaches or embodiments herein, the lubricant compositions may also comprise one or more optional ashless antioxidants, one or more optional oil-soluble molybdenum compounds, and one or more optional metal dihydrocarbyl dithiophosphate compounds in amounts effective to assist piston cleanliness when combined with the detergent and dispersant systems described above under the harsh conditions of the OM471 piston cleanliness test. In some embodiments, the lubricating oil composition further comprises an antioxidant system of one or more ashless antioxidants (preferably alkylated diphenylamines and hindered phenols) and a molybdenum-containing antioxidant. Examples of molybdenum-containing antioxidants include oil-soluble molybdenum compounds selected from the group consisting of molybdenum dithiocarbamates, molybdenum dialkyldithiophosphates, sulfur-free molybdenum complexes of organic amides, or mixtures thereof. The one or more ashless antioxidants can be selected from hindered phenols, aromatic amines, alkylated diphenylamines, phenyl-α-naphthylamines, alkylated phenyl-α-naphthylamines, hindered non-aromatic amines, sulfurized olefins, or mixtures thereof. In one embodiment, the lubricating composition comprises at least about 2 weight percent, at least about 2.2 weight percent, or at least about 2.5 weight percent of the antioxidant system, and in some embodiments, comprises about 5 weight percent or less, about 4 weight percent or less, or about 3 weight percent or less of the antioxidant system.One approach is for the antioxidant system to include at least 1.0 weight percent of diphenylamine, at least 1.0 weight percent of hindered phenol, and less than 0.2 weight percent of a molybdenum-containing compound in the lubricating composition.

[0013] In some approaches, one or more polyisobutylene succinimide dispersants in the dispersant system can be derived from highly reactive polyisobutylene having a number average molecular weight of about 1,200 to about 2,500, and include at least one borated polyisobutylene succinimide dispersant derived from polyisobutylene having a number average molecular weight of about 1,000 to about 1,500, which contributes about 100 to about 200 ppm of boron to the lubricating oil composition.

[0014] In other approaches or embodiments, the unique cleaning agent systems of this specification provide TBN from sulfonate cleaning agents in amounts of about 3 to about 15 mg KOH / g, about 5 to about 15 mg KOH / g, or about 8 to about 15 mg KOH / g, and include, consist of, or alternatively essentially consist of, calcium sulfonate cleaning agents in amounts that provide the cleaning agent systems TBN and soap content considered herein. In other words, the cleaning agent systems of this specification are primarily sulfonate cleaning agents, most preferably sulfonate-only cleaning agents that contain little to no phenate or other cleaning agent types (most preferably without phenate or other cleaning agent additives) that were previously required to pass previous heavy-duty diesel piston cleaning tests when using aluminum pistons. Surprisingly, even without other cleaning agent soap types, such as phenate soap, the lubricants of this specification pass the more stringent OM471 piston cleaning tests, even when using steel pistons. The cleansing agents described herein are substantially free of non-sulfonate soaps such as phenate soaps, meaning about 25 percent or less of phenate soap, about 20 percent or less, about 15 percent or less, about 10 percent or less, about 5 percent or less, about 2.5 percent or less, about 1 percent or less, or a non-functional amount of phenate soap.

[0015] As will be further discussed below, the cleansing agent systems of this specification may include unique blends of overbasic sulfonate cleansers and neutral to low-basic sulfonate cleansers configured to provide TBN levels and the soap content described. In some approaches or embodiments, the cleansing agent system includes a weight ratio of one or more overbasic sulfonate cleansers to one or more low-basic sulfonate cleansers of about 3:1 to about 8:1 (in other embodiments, about 3:1 to about 6:1, about 3:1 to about 5:1, or about 3:1 to about 4:1). In alternative approaches, the cleansing agent system includes embodiments having a weight ratio of overbasic sulfonate soap to low-basic sulfonate soap of about 2:1 to about 4:1 (in other embodiments, about 2.1:1 to about 3.5:1, about 2.2:1 to about 3:1, or about 2.3:1 to about 2.8:1). Preferably, the cleaning agent system comprises one or more overbasic sulfonate cleaning agents in an effective amount to provide the cleaning agent system with a minimum TBN of at least about 5 mg KOH / g, and one or more low-basic sulfonate cleaning agents in an effective amount to provide about 25 to about 40 weight percent of cleaning agent soap in the cleaning agent system.

[0016] Cleansing agents The lubricating compositions herein include cleaning agent systems that achieve piston cleanliness according to the demanding OM471 piston cleanliness test for steel pistons, with little to no non-sulfonate soaps, preferably no phenate soaps at all. In some approaches, steel piston cleanliness is achieved using a cleaning agent system that includes, consists of, or essentially consists of, one or more alkaline earth metal sulfonate cleaning agents, resulting in up to about 1 weight percent of sulfonate soap with a minimum TBN level provided by the sulfonate cleaning agent, which may be a blend of neutral, low-basic, or over-basic sulfonate cleaning agents. The preferred TBN levels provided by the sulfonate detergents are at least about 3 mg KOH / g, at least about 4 mg KOH / g, at least about 5 mg KOH / g, at least about 3 mg KOH / g to about 15 mg KOH / g, at least about 5 mg KOH / g to about 9 mg KOH / g, about 12 mg KOH / g or less, about 10 mg KOH / g or less, or about 7 mg KOH / g or less. In embodiments, the detergent systems of this specification generally contain one or more alkalis or alkali metal salts of sulfonates and contain only small amounts, residual levels, or preferably none of other functional detergent additives such as phenates, calixalates, salixalates, salicylates, carboxylic acids, their sulfurized derivatives, or combinations thereof, as long as the relationship between the minimum amount of sulfonate soap, TBN level, soap content, and / or the low levels of other detergents described herein is satisfied. Accordingly, in embodiments, the cleaning agent systems of this specification include a non-sulfonate cleaning agent in an amount of about 0.5% by weight or less, about 0.2% by weight or less, or about 0.1% by weight or less.

[0017] Suitable detergents and methods for their preparation are described in greater detail in a number of patent publications, including U.S. Patent No. 7,732,390 and the references cited therein, which are incorporated herein by reference. The lubricant compositions herein may contain from about 0.1 to about 5 weight percent of the individual and / or total detergent additives, from about 0.15 to about 3 weight percent in other approaches, and from about 0.5 to 2.6 weight percent in still other approaches of the individual and / or total detergent additives, provided that the detergent additive meets the amounts of sulfonates and other relationships described herein.

[0018] As noted above and in some approaches, the detergent system provides a selected amount of sulfonate soap and TBN level, along with a certain amount of detergent metal. For example, the detergent system herein can provide an amount of total detergent metal that is greater than about 1200 ppm of metal, or in other approaches, from about 1200 ppm to about 3500 ppm of total metal, from about 1400 ppm to about 3000 ppm of total metal, or from about 2000 ppm to about 2500 ppm of total metal. In some approaches, the detergent metal is calcium, magnesium, and / or sodium. In other approaches, the detergent metal is calcium and / or magnesium, and in still further approaches, the detergent metal is preferably calcium only.

[0019] Generally, suitable detergents in the system may include petroleum sulfonic acids, and long-chain mono- or dialkylarylsulfonic acids where the aryl group is benzyl, tolyl, and xylyl, and / or linear or branched alkali or alkaline earth metal salts of various phenates or phenate derivatives, such as calcium, sodium, or magnesium. Examples of suitable detergents include, in addition to the required amount of sulfonate soap described above, the following low-basicity / neutral and overbased variations of detergents: calcium phenate, calcium sulfur-containing phenate, calcium sulfonate, calcium calixarate, calcium salixarate, calcium salicylate, calcium carboxylic acid, calcium phosphate, calcium mono- and / or di-thiophosphate, calcium alkylphenol, calcium sulfur-bonded alkylphenol compound, calcium methylene-bridged phenol, magnesium phenate, magnesium sulfur-containing phenate, magnesium sulfonate, magnesium calixarate, magnesium salixarate, magnesium salicylate, magnesium carboxylic acid, magnesium phosphate, magnesium mono- and / or di-thiophosphate, magnesium alkylphenol, magnesium sulfur-bonded alkylphenol compound, magnesium methylene-bridged phenol, sodium phenate, sodium sulfur-containing phenate, sodium sulfonate, sodium calixarate, sodium salixarate, sodium salicylate, sodium carboxylic acid, sodium phosphate, sodium mono- and / or di-thiophosphate, sodium alkylphenol, sodium sulfur-bonded alkylphenol compound, or sodium methylene-bridged phenol.

[0020] The detergent additives herein preferably include a blend of (i) an effective amount of a neutral to low-basicity detergent to provide a minimum soap content and (ii) an effective amount of an overbased detergent to meet a minimum detergent TBN number.

[0021] As can be understood, overbasic detergent additives are well known in the art and may be alkaline or alkaline earth metal overbasic detergent additives. Such detergent additives can be prepared by reacting a metal oxide or metal hydroxide with a substrate and carbon dioxide gas. The substrate is typically an acid, such as an aliphatic-substituted sulfonic acid, an aliphatic-substituted carboxylic acid, or an aliphatic-substituted phenol.

[0022] The term "overbasic" refers to metal salts in which the amount of metal present exceeds the stoichiometric amount, such as metal salts of sulfonates, carboxylates, salicylates, and / or phenates. Such salts may have a conversion level greater than 100% (i.e., such salts may contain more than 100% of the theoretical amount of metal required to convert an acid to its "standard" or "neutral" salt). The expression "metal ratio," often abbreviated as MR, is used to indicate the ratio of the total stoichiometric equivalents of metal in an overbasic salt to the stoichiometric equivalents of metal in a neutral salt, according to known chemical reactivity and stoichiometry. For standard or neutral salts, MR is 1, and for overbasic salts, MR is greater than 1. They are commonly referred to as overbasic, highly basic, or ultrabasic salts and may be salts of organic sulfur acids, carboxylic acids, or phenols.

[0023] As used herein, the term "TBN" is used to represent the total base number in units of mg KOH / g, as measured by the method of ASTM D2896. Detergents may be neutral or overbasic. For example, a low-basic or neutral detergent may have a total base number (TBN) of up to about 175 mg KOH / gram. In another example, an overbasic detergent in the lubricating oil composition herein may have a total base number (TBN) of about 200 mg KOH / gram or more, or about 250 mg KOH / gram or more, or about 350 mg KOH / gram or more, or about 375 mg KOH / gram or more, or about 400 mg KOH / gram or more. Overbasic detergents may have a metal-to-substrate ratio of 1.1:1 or less, or 2:1 or less, or 4:1 or less, or 5:1 or less, or 7:1 or less, or 10:1 or less, or 12:1 or less, or 15:1 or less, or 20:1 or less.

[0024] Suitable examples of perbasic detergents include (insofar as they satisfy the sulfonate soaps and other TBN relationships described herein) perbasic calcium phenates, perbasic calcium sulfur-containing phenates, perbasic calcium sulfonates, perbasic calcium calixalates, perbasic calcium salixalates, perbasic calcium salicylates, perbasic calcium carboxylic acids, perbasic calcium phosphates, perbasic calcium mono- and / or di-thiophosphates, perbasic calcium alkylphenols, perbasic calcium sulfur-bonded alkylphenol compounds, and perbasic calcium me Examples include, but are not limited to, ethylene-crosslinked phenols, overbasic magnesium phenates, overbasic magnesium sulfur-containing phenates, overbasic magnesium sulfonates, overbasic magnesium calixalates, overbasic magnesium salixalates, overbasic magnesium salicylates, overbasic magnesium carboxylic acids, overbasic magnesium phosphates, overbasic magnesium mono- and / or di-thiophosphates, overbasic magnesium alkylphenols, overbasic magnesium sulfur-bonded alkylphenol compounds, or overbasic magnesium methylene-crosslinked phenols.

[0025] Low basic or neutral detergents generally have a TBN of up to 175 mg KOH / g, up to 150 mg KOH / g, up to 100 mg KOH / g, or up to 50 mg KOH / g. Low basic / neutral detergents may include calcium-containing detergents. Suitable examples of low basic / neutral detergents include, but are not limited to, calcium sulfonate, calcium carbonate, calcium salicylate, magnesium sulfonate, magnesium phenate, and / or magnesium salicylate (as long as they satisfy the sulfonate soap and other TBN relationships described herein).

[0026] In some embodiments, the detergent used in the lubricants herein comprises at least overbasic calcium sulfonate having a total base number of 200–400, and in other approaches, about 250–350. The above TBN values ​​reflect the values ​​of the finished detergent component diluted in the base oil. In some approaches, the detergent system comprises a blend of neutral to low-basic and overbasic sulfonate detergents, and the lubricants herein may contain about 0.1–about 1.0 weight percent of neutral to low-basic sulfonate detergent and about 0.5–about 3.0 weight percent of overbasic sulfonate detergent (or in other approaches, about 1.0–about 2.5 weight percent of overbasic sulfonate detergent). In yet another approach, the detergent system herein may have a ratio of overbasic sulfonate detergent to low-basic sulfonate detergent of about 3:1–about 8:1. As described above, the amount of overbasic sulfonate detergent is effective in providing the detergent with a minimum TBN level, and the amount of low-basic or neutral sulfonate detergent is effective in providing a minimum soap level.

[0027] In other embodiments, the TBN of the cleaning agents herein may reflect neat or undiluted versions of the cleaning agent components. For example, the fluids herein may include overbasic calcium sulfonate as a neat additive having a TBN of about 500 to about 650, and in other approaches, about 550 to about 610. The fluids herein may also include neutral to low-basic calcium sulfonate as a neat additive having a TBN of up to 75, up to 70, or about 40 to about 75, or about 40 to about 70.

[0028] More specifically, the cleaning agent systems of this specification include neutral, low-basic, and / or over-basic cleaning agents (preferably neutral to over-basic calcium sulfonate) to achieve a cleaning agent TBN of at least about 3 mg KOH / g, at least about 4 mg KOH / g, at least about 5 mg KOH / g, at least about 3 mg KOH / g to about 15 mg KOH / g or less, about 5 mg KOH / g or less, or about 9 mg KOH / g or less, as measured by ASTM D2896. Preferably, the cleaning agent systems of this specification include one or more over-basic sulfonate cleaning agents in an effective amount to provide at least about 5 mg KOH / g to about 8 mg KOH / g of the total TBN of the cleaning agent system.

[0029] The cleaning agent systems herein have a high sulfonate soap content relative to the total soap content, and in particular, the cleaning agent systems have at least about 75 percent sulfonate soap, other approaches have at least about 80 percent sulfonate soap, at least about 85 percent sulfonate soap, at least about 90 percent sulfonate soap, at least about 95 percent sulfonate soap, at least about 98 percent sulfonate soap, at least about 99 percent sulfonate soap, or about 100 percent sulfonate soap (or any range in between). In other approaches, the soap content of the cleaning agent is balanced with a selected cleaning agent TBN level to achieve steel piston cleaning with little or no use of phenate cleaning agents. In some approaches, the cleaning agent systems of the lubricants herein, in particular heavy-duty lubricants, are substantially free of magnesium sulfonate cleaning agents, substantially free of phenate cleaning agents, or a combination thereof. As used herein, substantially no substance means less than or equal to about 1% by weight, less than or equal to 0.5% by weight, less than or equal to about 0.25% by weight, less than or equal to about 0.1% by weight, or none at all.

[0030] In other approaches, the cleansing agent systems of this specification have a selected weight ratio of sulfonate soap to phenate soap in the cleansing agent system of about 75:25 or greater, about 80:20 or greater, about 85:15 or greater, about 90:10 or greater, and even about 95:5 or about 99:1 or greater (in the context of this ratio, greater than or equal to mean that there is more sulfonate soap than phenate soap). Preferably, the cleansing agent systems of this specification contain only residual levels of phenate soap, salicylate soap, calixalate soap, or non-sulfonate soap, if any. Preferably, the cleansing agent system contains one or more low-basic sulfonate cleansing agents in an effective amount to provide about 30 to about 50 weight percent of cleansing soap.

[0031] Soap content generally refers to the amount of neutral organic salts and reflects the cleaning ability, or detergent power, and dirt-lifting ability of a detergent. The soap content of a lubricant can be determined by ASTM D3712. A more detailed explanation of "soap content" is known to those skilled in the art and is described under subheading 7.2.5. Detergent Classification on pages 219-220 of the standard textbook entitled "Chemistry and Technology of Lubricants," 3rd edition, edited by RMMortier and STOrszulik, copyright 2010, which is incorporated herein by reference.

[0032] Dispersant system The lubricating oil compositions of this specification, in particular heavy-duty crankcase lubricating oil compositions, also include a dispersant system comprising one or more polyisobutylene succinimide dispersants that contribute to the lubricating oil composition in an amount of at least about 5 weight percent of one or more dispersants (or, in other approaches, about 5 to about 15 weight percent, about 6 to about 12 weight percent, or about 6 to about 10 weight percent of one or more dispersants). Preferably, the one or more polyisobutylene succinimide dispersants are derived from highly reactive polyisobutylene having a number average molecular weight of about 1,200 to about 2,500, and in some embodiments, may include at least one borated polyisobutylene succinimide dispersant derived from highly reactive polyisobutylene having a number average molecular weight of about 1,000 to about 1,500 and contributing about 100 to about 200 ppm of boron to the lubricating oil composition. In some embodiments, the dispersant brings more than 650 ppm of nitrogen, preferably about 650 to about 1500 ppm, to the lubricating oil composition. In some approaches or embodiments, the dispersant may be diluted with about 25 to about 50 weight percent of a suitable process oil.

[0033] Dispersants are often known as ashless dispersants because they do not contain ash-forming metals before being mixed into a lubricant composition, and they do not typically contribute to any ash when added to the lubricant. Ashless dispersants are characterized by polar groups being bonded to relatively high molecular weight hydrocarbon chains. Typical ashless dispersants include N-substituted long-chain alkenyl succinimides. Examples of nitrogen-substituted long-chain alkenyl succinimides include polyisobutylene succinimides in which, as measured by GPC, the number-average molecular weight of the polyisobutylene substituents is in the range of about 350 to about 5,000, or about 3,000, or about 2,000, or about 1,500. Succinimide dispersants and their preparations are disclosed, for example, in U.S. Patent No. 7,897,696 and U.S. Patent No. 4,234,435, which are incorporated herein by reference. Alkenyl substituents can be prepared from polymerizable monomers containing about 2 to about 16 carbon atoms, or about 2 to about 8 carbon atoms, or about 2 to about 6 carbon atoms. Succinimide dispersants are typically imides formed from polyamines (typically poly(ethyleneamine)).

[0034] In the approach, preferred amines for the dispersant may be selected from polyamines and hydroxylamines. Examples of polyamines that may be used include, but are not limited to, diethylene triamine (DETA), triethylene tetramine (TETA), tetraethylene pentamine (TEPA), and higher homologues such as pentaethylamine hexamine (PEHA). In some approaches, so-called heavy polyamines may be used, which are polyalkylene-polyamine mixtures containing small amounts of lower polyamine oligomers such as TEPA and PEHA (pentaethylenehexamine), but mainly containing six or more nitrogen atoms, two or more primary amines per molecule, and oligomers with broader branching than conventional polyamine mixtures. Heavy polyamines preferably contain polyamine oligomers containing seven or more nitrogen atoms per molecule and two or more primary amines per molecule.

[0035] In some embodiments, polyisobutylene (PIB), if included, is a preferred reactant for forming a dispersant and may have a terminal double bond content of more than 50 mol%, more than 60 mol%, more than 70 mol%, more than 80 mol%, or more than 90 mol%. Such PIBs are also referred to as highly reactive PIBs ("HR-PIBs"). HR-PIBs having a number-average molecular weight in the range of about 800 to about 5000 as determined by GPC are preferred for use in embodiments of this disclosure. Conventional PIBs typically have a terminal double bond content of less than 50 mol%, less than 40 mol%, less than 30 mol%, less than 20 mol%, or less than 10 mol%.

[0036] HR-PIBs having a number-average molecular weight in the range of about 900 to about 3,000, as determined by GPC, may be preferred. Such HR-PIBs are commercially available or can be synthesized by polymerization of isobutene in the presence of a non-chlorinating catalyst such as boron trifluoride, as described in U.S. Patents 4,152,499 and 5,739,355. When used in the aforementioned thermal ene reaction, HR-PIBs may result in a higher conversion rate and less precipitate formation in the reaction due to their increased reactivity. A preferred method is described in U.S. Patent 7,897,696. In one embodiment, the disclosure further comprises at least one dispersant derived from polyisobutylene succinic anhydride, "PIBSA". PIBSA may have an average succinic acid moiety of about 1.0 to about 2.0 per polymer.

[0037] In one embodiment, the dispersant may be derived from polyalphaolefin (PAO) succinic anhydride. In another embodiment, the dispersant may be derived from olefin maleic anhydride copolymer. In yet another embodiment, the dispersant may be described as poly-PIBSA. In one embodiment, the dispersant may be derived from an anhydride grafted onto an ethylene-propylene copolymer.

[0038] A suitable class of nitrogen-containing dispersants can be derived from olefin copolymers (OCPs), more specifically from ethylene-propylene dispersants that can be grafted with maleic anhydride. A more complete list of nitrogen-containing compounds that can be reacted with functionalized OCPs is described and / or commercially available in U.S. Patents Nos. 7,485,603, 7,786,057, 7,253,231, 6,107,257, and 5,075,383.

[0039] One class of suitable dispersants may also be Mannich bases. Mannich bases are materials formed by the condensation of higher molecular weight alkyl-substituted phenols, polyalkylene polyamines, and aldehydes such as formaldehyde. Mannich bases are described in detail in U.S. Patent No. 3,634,515. Another class of suitable dispersants may also be high molecular weight esters or semi-esteramides.

[0040] In some approaches, the dispersants in the lubricants herein may be optionally post-treated by conventional methods involving reaction with a variety of agents. Suitable post-treatment agents include boron, urea, thiourea, dimercaptothiadiazole, carbon disulfide, aldehydes, ketones, carboxylic acids, hydrocarbon-substituted succinic anhydride, maleic anhydride, nitriles, epoxides, carbonates, cyclic carbonates, hindered phenol esters, and phosphorus compounds. (See, for example, U.S. Patents 7,645,726, 7,214,649, 8,048,831, and 5,241,003, all of which are incorporated herein by reference.)

[0041] The boron compound used as a post-treatment reagent can be selected from boron oxide, boron halides, boric acid, and esters of boric acid in amounts that provide boron in an atomic proportion of about 0.1 per mole of nitrogen composition to about 20 per atomic proportion of nitrogen used. The boron-post-treated dispersant may contain about 0.05 to about 2.0 weight percent of boron, or by other approaches, about 0.5 to about 1.0 weight percent of boron, based on the total weight of the boric acid dispersant.

[0042] In other approaches, carboxylic acids may also be used as work-up reagents and may be saturated or unsaturated mono-, di-, or polycarboxylic acids. Examples of carboxylic acids include, but are not limited to, maleic acid, fumaric acid, succinic acid, and naphthalidic acid (e.g., 1,8-naphthalidic acid). Anhydrides may also be used as work-up reagents and can be selected from the group consisting of mono-unsaturated anhydrides (e.g., maleic anhydride), alkyl or alkylene-substituted cyclic anhydrides (e.g., succinic anhydride or glutamic anhydride), and aromatic carboxylic anhydrides (including naphthalic anhydride, e.g., 1,8-naphthalic anhydride).

[0043] In one embodiment, the process for post-treating the dispersant includes first forming a succinimide product as described above, and then further reacting the succinimide product with a post-treatment agent such as a boron compound such as boric acid. In some cases, the dispersants of this specification may be post-treated with more than one post-treatment agent. For example, the dispersant may be post-treated with a boron compound such as boric acid and also with an anhydride such as maleic anhydride. In some cases, the dispersant may be post-treated with an anhydride such as maleic anhydride and / or 1,8-naphthalic anhydride.

[0044] In addition to the post-treatments described above, dispersants may be post-treated with a variety of post-treatments designed to improve or impart different properties. Such post-treatments include those summarized in columns 27-29 of U.S. Patent No. 5,241,003, which is incorporated herein by reference. Such treatments include treatments by: inorganic phosphoric acid or anhydride (e.g., U.S. Patents No. 3,403,102 and 4,648,980); organophosphorus compounds (e.g., U.S. Patent No. 3,502,677); phosphorus pentasulfide; boron compounds as already described above (e.g., U.S. Patents No. 3,178,663 and 4,652,387); carboxylic acids, polycarboxylic acids, anhydrides, and / or acid halides (e.g., U.S. U.S. Patent Nos. 3,708,522 and 4,948,386); Epoxy polyepoxyates or thioepoxides (e.g., U.S. Patent Nos. 3,859,318 and 5,026,495); Aldehydes or ketones (e.g., U.S. Patent No. 3,458,530); Carbon disulfide (e.g., U.S. Patent No. 3,256,185); Glycidol (e.g., U.S. Patent No. 4,617,137); Urea, thiourea, or guanidine (e.g., U.S. Japanese Patent Nos. 3,312,619, 3,865,813, and British Patent No. 1,065,595); Organic sulfonic acids (e.g., U.S. Patent No. 3,189,544 and British Patent No. 2,140,811); Alkenyl cyanides (e.g., U.S. Patents No. 3,278,550 and 3,366,569); Diketene (e.g., U.S. Patent No. 3,546,243); Diisocyanates (e.g., U.S. Patent No. 3,573,205); A Lucansultones (e.g., U.S. Patent No. 3,749,695); 1,3-dicarbonyl compounds (e.g., U.S. Patent No. 4,579,675); alkoxylated alcohols or phenolic sulfates (e.g., U.S. Patent No. 3,954,639); cyclic lactones (e.g., U.S. Patents No. 4,617,138, 4,645,515, 4,668,246, 4,963,275, and 4,971,711);Cyclic carbonates or thiocarbonates, linear monocarbonates or polycarbonates, or chloroformates (e.g., U.S. Patent Nos. 4,612,132, 4,647,390, 4,648,886, and 4,670,170); nitrogen-containing carboxylic acids (e.g., U.S. Patent No. 4,971,598 and British Patent No. 2,140,811); hydroxy-protected chlorodicarbonyloxy compounds (e.g., U.S. Patent No. 4,614,522); lactams, thiolactams, thiolactones, or dithiolactones (e.g., U.S. Patents No. 4,614,603 and No. 4,666,460); cyclic carbonates or thiocarbonates, linear monocarbonates or polycarbonates, or chloroformates (e.g., U.S. Patents No. 4,612,132, 4,647,390, 4,646,860, and 4,670,170); nitrogen-containing carboxylic acids (e.g., U.S. Patent No. 4,971,598 and British Patent No. 2,440,811); hydroxy-protected chlorodicarbonyloxy compounds (e.g., U.S. Patent No. 4,614,522); lactams, thiocarbonates Olactams, thiolactones, or dithiolactones (e.g., U.S. Patent Nos. 4,614,603 and 4,666,460); cyclic carbamates, cyclic thiocarbamates, or cyclic dithiocarbamates (e.g., U.S. Patents Nos. 4,663,062 and 4,666,459); hydroxyaliphatic carboxylic acids (e.g., U.S. Patents Nos. 4,482,464, 4,521,318 and 4,713,189); oxidizing agents (e.g., U.S. Patent No. 4,379,064); combinations of phosphorus pentasulfide and polyalkylene polyamines (e.g., (e.g., U.S. Patent No. 3,185,647); combinations of carboxylic acids or aldehydes or ketones and sulfur or sulfur chloride (e.g., U.S. Patents No. 3,390,086 and 3,470,098); combinations of hydrazine and carbon disulfide (e.g., U.S. Patent No. 3,519,564); combinations of aldehydes and phenols (e.g., U.S. Patents No. 3,649,229, 5,030,249 and 5,039,307); combinations of aldehydes and O-diesters of dithiophosphate (e.g., U.S. Patent No. 3,865,740);Combinations of hydroxyaliphatic carboxylic acids and boric acid (e.g., U.S. Patent No. 4,554,086); combinations of hydroxyaliphatic carboxylic acids followed by formaldehyde and phenol (e.g., U.S. Patent No. 4,636,322); combinations of hydroxyaliphatic carboxylic acids and followed by aliphatic dicarboxylic acids (e.g., U.S. Patent No. 4,663,064); combinations of formaldehyde and phenol, followed by glycolic acid (e.g., U.S. Patent No. 4,699,724); combinations of hydroxyaliphatic carboxylic acids or oxalic acid followed by diisocyanates (e.g., U.S. Patent No. 4,713,191); inorganic acids or anhydrides of phosphorus or combinations of partially or entirely sulfur analogs and boron compounds (e.g., U.S. Patent No. 4,857,214); combinations of organic diacids, followed by unsaturated fatty acids, followed by nitroso-aromatic amines, optionally followed by boron compounds, and followed by glycosylation agents (e.g., U.S. Patent No. 4,973,412); combinations of aldehydes and triazoles (e.g., U.S. Patent No. 4,963,278); combinations of aldehydes and triazoles followed by boron compounds (e.g., U.S. Patent No. 4,981,492); combinations of cyclic lactones and boron compounds (e.g., U.S. Patents No. 4,963,275 and 4,971,711). The aforementioned patents are incorporated herein by reference in their entirety.

[0045] In other approaches, the total amount of dispersant in the dispersant system can be present in an amount of up to about 15 weight percent of the lubricating composition, and one or more of the dispersants are post-treated to provide the lubricating composition with at least about 40 ppm and up to 300 ppm of boron (preferably about 100 to about 200 ppm of boron). In other approaches, based on the final weight of the lubricating oil composition, the total amount of dispersant that can be used in the lubricating composition is about 5 to about 15 weight percent, or about 6 to about 10 weight percent, about 7.0 to about 10 weight percent, or about 7.0 to about 8 weight percent. As described above, in some approaches, the dispersant may be diluted with about 25 to about 50 weight percent of process oil. The dispersant can provide at least about 400 ppm of nitrogen, and up to about 1,500 ppm of nitrogen, preferably about 650 ppm to about 1,500 ppm of nitrogen, and more preferably about 800 ppm to about 1,200 ppm of nitrogen.

[0046] A suitable dispersant may have a TBN of approximately 5 to 30 TBN when measured in a dispersant sample containing approximately 50% diluted oil, and a KOH / g concentration of approximately 10 to 60 mg on an oil-free basis. TBN is measured by the method of ASTM D2896.

[0047] Oil-soluble molybdenum compounds The crankcase lubricants of this disclosure, in particular heavy-duty crankcase lubricants, may optionally contain one or more oil-soluble molybdenum-containing compounds. The oil-soluble molybdenum compounds may have the functional properties of abrasion inhibitors, antioxidants, friction modifiers, or mixtures thereof. The oil-soluble molybdenum compounds may be any of the following: molybdenum dithiocarbamates, molybdenum dialkyldithiophosphates, molybdenum sulfides, molybdenum disulfides, molybdenum dithiophosphinates, amine salts of molybdenum compounds, molybdenum xanthanates, molybdenum thioxanthanates, molybdenum sulfides, molybdenum carboxylates, molybdenum alkoxides, trinuclear organic molybdenum compounds, and / or mixtures thereof. The molybdenum-containing compounds may be sulfur-containing compounds or sulfur-free compounds. Molybdenum disulfide may be in the form of a stable dispersion.

[0048] In one embodiment, the oil-soluble molybdenum compound can be selected from the group consisting of molybdenum dithiocarbamates, molybdenum dialkyldithiophosphates, sulfur-free molybdenum complexes of organic amides, and mixtures thereof. In one embodiment, the oil-soluble molybdenum compound may be a molybdenum dithiocarbamate. An exemplary sulfur-free molybdenum complex of organic amide is disclosed in U.S. Patent No. 5,137,647.

[0049] In one approach or embodiment, a suitable molybdenum dithiocarbamate may be represented by the formula,

[0050] [ka] In the formula, R 5 , R 6 , R 7 , and R 8 Each of these is independently a hydrogen atom, C1~C 20 Alkyl alkyl groups, C6-C 20 C3-C3 compounds containing cycloalkyl, aryl, alkylaryl, or aralkyl groups, or optionally, esters, ethers, alcohols, or carboxyl groups.20 is a hydrocarbyl group, and X1, X2, Y1 and Y2 are each independently a sulfur atom or an oxygen atom. R 5 , R 6 , R 7 , and R 8 Examples of suitable groups for each of are 2-ethylhexyl, nonylphenyl, methyl, ethyl, n-propyl, iso-propyl, n-butyl, t-butyl, n-hexyl, n-octyl, nonyl, decyl, dodecyl, tridecyl, lauryl, oleyl, linoleyl, cyclohexyl and phenylmethyl. In other approaches, R 5 , R 6 , R 7 , and R 8 may each have a C6-C 18 alkyl group. X1 and X2 may be the same, and Y1 and Y2 may be the same. X1 and X2 may both contain a sulfur atom, and Y1 and Y2 may both contain an oxygen atom. Further examples of molybdenum dithiocarbamate include C6-C 18 dialkyl or diaryl dithiocarbamate, or alkyl-aryl dithiocarbamate such as dibutyl-, diamyl-, di-(2-ethylhexyl)-, dilauryl-, dioleyl-, and dicyclohexyl-dithiocarbamate.

[0051] Suitable examples of molybdenum compounds that can be used include Molyvan® 822, Molyvan® A, Molyvan® 2000, Molyvan® 807, Molyvan® 855, and Molyvan® 1055 from RTVanderbilt Co., Ltd., and commercially available substances sold under trade names such as Sakura-Lube® S-165, S-200, S-300, S-310G, S-525, S-600, S-700, and S-710 from Adeka Corporation, as well as mixtures thereof. Suitable molybdenum components are described in U.S. Patent No. 5,650,381, U.S. Reissue Patent No. 37,363(E1), U.S. Reissue Patent No. 38,929(E1), and U.S. Reissue Patent No. 40,595(E1), which are incorporated herein by reference in their entirety.

[0052] In one embodiment, when included in the formulation, the oil-soluble molybdenum compound may be present in the crankcase lubricants of this specification, particularly heavy-duty crankcase lubricants, in amounts that provide up to about 800 ppm of molybdenum, or about 5 ppm to 800 ppm of molybdenum. In other embodiments, the oil-soluble molybdenum compound may be present in amounts that provide about 10 to about 500 ppm of molybdenum, about 20 to 250 ppm of molybdenum, about 30 to 175 ppm of molybdenum, about 40 to 150 ppm of molybdenum, about 50 to 125 ppm of molybdenum, or about 60 to 100 ppm of molybdenum.

[0053] Antioxidant The crankcase lubricants of this specification, in particular the heavy-duty crankcase lubricants, may also contain one or more antioxidants, preferably one or more amine-based antioxidants. When used, the antioxidants may be provided in an amount of about 1 to about 5 weight percent (or, in other approaches, about 1.2 to about 4 weight percent, or about 1.4 to about 3 weight percent, or about 2 to about 3 weight percent), thereby assisting piston cleanliness on steel pistons in the harsh conditions of the OM471 test when combined with the dispersant and detergent systems of this specification.

[0054] Suitable antioxidants include, for example, phenates, phenate sulfides, sulfurized olefins, phosphosulfur terpenes, sulfurized esters, aromatic amines, alkylated diphenylamines (e.g., nonyldiphenylamine, di-nonyldiphenylamine, octyldiphenylamine, dioctyldiphenylamine), phenyl-alpha-naphthylamines, alkylated phenyl-alpha-naphthylamines, hindered non-aromatic amines, phenols, hindered phenols, oil-soluble molybdenum compounds, polymeric antioxidants, or mixtures thereof. Antioxidant compounds can be used alone or in combination.

[0055] In some approaches or embodiments, suitable amine antioxidants may include, but are not limited to, aromatic amines, alkylated diphenylamines, phenyl-α-naphthylamines, alkylated phenyl-α-naphthylamines, hindered non-aromatic amines, or combinations thereof. The total amount of antioxidants in the lubricating compositions herein may be present in amounts resulting in up to about 400 ppm of nitrogen, or up to about 300 ppm of nitrogen, or up to about 200 ppm of nitrogen, or about 50 to about 400 ppm of nitrogen, about 60 to about 300 ppm of nitrogen, about 70 to about 200 ppm of nitrogen, or about 80 to about 100 ppm of nitrogen. In other approaches, the lubricating compositions herein may contain up to about 5 weight percent of amine antioxidants, or about 0.1 to about 5 weight percent of amine antioxidants, and in other approaches, about 0.2 to about 3 weight percent, or about 0.2 to about 2.0 weight percent of amine antioxidants.

[0056] In some approaches, the amine antioxidant may be one or more aromatic amine antioxidants, and may include, but is not limited to, diarylamines having the following formulas.

[0057] [ka] In the formula, R' and R'' each independently represent a substituted or unsubstituted aryl group having 6 to 30 carbon atoms. When substituted, preferred substituents for the aryl groups R' and R'' include aliphatic hydrocarbon groups such as alkyls having 1 to 30 carbon atoms, hydroxyl groups, halogen radicals, carboxylic acid or ester groups, or nitro groups. The aryl groups may be substituted or unsubstituted phenyl or naphthyl groups, particularly one or both aryl groups being substituted with at least one alkyl group having 4 to 30 carbon atoms, preferably 4 to 18, most preferably 4 to 9 carbon atoms. In the approach, one or both aryl groups may be substituted with mono-alkylated diphenylamines, di-alkylated diphenylamines, C9 alkylated diphenylamines, or mixtures of mono- and dialkylated diphenylamines.

[0058] Examples of diarylamines that may be used include, but are not limited to, diphenylamine; various alkylated diphenylamines, 3-hydroxydiphenylamine, N-phenyl-1,2-phenylenediamine, N-phenyl-1,4-phenylenediamine, monobutyldiphenylamine, dibutyldiphenylamine, monooctyldiphenylamine, dioctyldiphenylamine, monononyldiphenylamine, dinonyldiphenylamine, monotetradecyldiphenylamine, ditetradecyldiphenylamine, phenyl-alpha-naphthylamine, monooctylphenyl-alpha-naphthylamine, phenyl-beta-naphthylamine, monoheptyldiphenylamine, diheptyldiphenylamine, p-oriented styrene-diphenylamine, mixed butyloctyldiphenylamine, and mixed octylstyryldiphenylamine.

[0059] In other approaches, suitable antioxidants may include aromatic amine antioxidants. Examples of phenolic antioxidants include N,N'-di-sec-butylphenylene-diamine, 4-isopropylaminodiphenylamine, phenyl-alpha-naphthylamine, phenyl-alpha-naphthylamine, and cyclic alkylated diphenylamines.

[0060] Hindered phenol antioxidants may contain secondary butyl groups and / or tertiary butyl groups as sterically hindering groups. The phenol group may be further substituted with a hydrocarbyl group and / or a crosslinking group bonded to a second aromatic group. Examples of suitable hindered phenol antioxidants include 2,6-di-tert-butylphenol, 4-methyl-2,6-di-tert-butylphenol, 4-ethyl-2,6-di-tert-butylphenol, 4-propyl-2,6-di-tert-butylphenol, or 4-butyl-2,6-di-tert-butylphenol, or 4-dodecyl-2,6-di-tert-butylphenol. In one embodiment, the hindered phenol antioxidant may be an ester, but may include, for example, Irganox® L-135 available from BASF or an addition product derived from 2,6-di-tert-butylphenol and an alkyl acrylate, where the alkyl group may contain about 1 to about 18 carbon atoms, or about 2 to about 12 carbon atoms, or about 2 to about 8 carbon atoms, or about 2 to about 6 carbon atoms, or about 4 carbon atoms. Another commercially available hindered phenol antioxidant may be an ester, but may include Ethanox® 4716 available from Albemarle Corporation.

[0061] Useful antioxidants may include diarylamines and high molecular weight phenols. In some embodiments, the lubricating oil composition may contain a mixture of diarylamines and high molecular weight phenols, so that each antioxidant may be present in an amount sufficient to provide up to about 5% by weight, based on the final weight of the lubricating oil composition. In some embodiments, the antioxidant may be a mixture of about 0.3 to about 1.5% by weight of diarylamine and about 0.4 to about 2.5% by weight of high molecular weight phenol, based on the final weight of the lubricating oil composition.

[0062] Suitable olefins that can be sulfurized to form sulfurized olefins include propylene, butylene, isobutylene, polyisobutylene, pentene, hexene, heptene, octene, nonene, decene, undecene, dodecene, tridecene, tetradecene, pentadecene, hexadecene, heptadecene, octadecene, nonadecene, eicosene, or mixtures thereof. In one embodiment, hexadecene, heptadecene, octadecene, nonadecene, eicosene, or mixtures thereof, as well as their dimers, trimers, and tetramers, are particularly useful olefins. Alternatively, the olefins may be Diels-Alder adducts of dienes such as 1,3-butadiene and unsaturated esters such as butyl acrylate.

[0063] Another class of sulfurized olefins includes sulfurized fatty acids and their esters. Fatty acids are often obtained from vegetable or animal oils and typically contain about 4 to about 22 carbon atoms. Suitable examples of fatty acids and their esters include triglycerides, oleic acid, linoleic acid, palmitoleic acid, or mixtures thereof. Often, fatty acids are obtained from lard oil, tall oil, peanut oil, soybean oil, cottonseed oil, sunflower seed oil, or mixtures thereof. Fatty acids and / or esters can be mixed with olefins such as α-olefins.

[0064] Metal dihydrocarbyl dithiophosphate compounds The crankcase lubricants described herein, in particular heavy-duty crankcase lubricants, may optionally contain one or more metal dihydrocarbyl dithiophosphate compounds, such as zinc dihydrocarbyl dithiophosphate (ZDDP), but are not limited to the following. When used, one or more metal dihydrocarbyl dithiophosphate compounds can provide the lubricant, in particular heavy-duty lubricants, with at least about 500 ppm of phosphorus, or by other approaches, about 600 ppm to about 1200 ppm of phosphorus, or about 700 ppm to about 1000 ppm of phosphorus, or about 700 ppm to about 1200 ppm of phosphorus. When used herein, the metal dihydrocarbyl dithiophosphate compounds preferably contain a hydrocarbyl group derived from a mixture of primary and secondary alcohols.

[0065] A suitable metal dihydrocarbyl dithiophosphate compound may contain 5 to about 10 weight percent of metal (e.g., about 6 to about 9 weight percent of a metal such as zinc) and about 8 to about 18 weight percent of sulfur (e.g., about 12 to about 18 weight percent of sulfur, or about 8 to about 15 weight percent of sulfur). A suitable metal dihydrocarbyl dithiophosphate compound may contain a dihydrocarbyl dithiophosphate metal salt, the metal of which may be an alkali metal, an alkaline earth metal, aluminum, lead, tin, molybdenum, manganese, nickel, copper, titanium, zirconium, zinc, or a combination thereof. Preferably, the metal is zinc.

[0066] The alkyl groups on the metal dihydrocarbyl dithiophosphate compounds herein may be derived from primary alcohols, secondary alcohols, phenols, and / or mixtures thereof, preferably mixtures of primary and secondary alcohols. For example, all alkyl groups or hydrocarbyl groups on the metal dihydrocarbyl dithiophosphate compounds herein may be derived from primary alcohols (such as 2-ethylhexyl alcohol) and / or mixtures of primary and secondary alcohols (e.g., 2-ethylhexanol, isobutanol, and isopropanol). For example, in one embodiment, about 60 mol percent or more of alkyl groups are derived from the primary alcohol 2-ethylhexanol and / or isobutyl alcohol, and about 40 mol percent or less of alkyl groups are derived from secondary alcohols (such as isopropyl alcohol, methyl isobutylcarbinol, and / or combinations thereof). In an optional embodiment, all alkyl groups on the metal dihydrocarbyl dithiophosphate compounds may be derived from primary alcohols such as 2-ethylhexanol or others described below. Preferably, the metal dihydrocarbyl dithiophosphate compound is a ZDDP obtained from 60 to 80 mole percent of 2-ethylhexanol and / or isobutyl alcohol and 20 to 40 mole percent of isopropyl alcohol, and may contain about 6 to about 10 weight percent of phosphorus, about 7 to about 9 weight percent of zinc, and about 15 to about 20 weight percent of sulfur.

[0067] The metal dihydrocarbyl dithiophosphate compounds described herein may be derived from alcohols selected from, but are not limited to, 2-ethylhexanol, methylheptanol, heptanol, octanol, nonanol, decanol, dodecanol, and / or their isovariants. Examples of suitable metal dihydrocarbyl dithiophosphate compounds include zinc O,O-di(C) 8~14Examples include, but are not limited to, zinc O,O-(2-methylbutyl)-O-(2-methylpropyl) dithiophosphate; zinc O,O-(3-methylbutyl)-O-(2-methylpropyl) dithiophosphate; zinc O,O-(2-methylbutyl)-O-(2-methylpropyl) dithiophosphate; and zinc O,O-(2-methylbutyl)-O-(2-methylpropyl) dithiophosphate, or combinations thereof.

[0068] In the approach or embodiment described herein, a metal dihydrocarbyl dithiophosphate compound suitable for heavy-duty crankcase lubricants is, formula I:

[0069] [ka] (In the formula, each R in formula I independently contains 6 to 18 carbon atoms, or 6 to 12 carbon atoms, or about 8 to 10 carbon atoms, provided that each phosphorus atom has an average of at least 14 total carbon atoms, preferably at least 8 total carbon atoms or 8 to 16 total carbon atoms) and may have a structure. For example, each R independently may be ethyl, n-propyl, i-propyl, n-butyl, i-butyl, sec-butyl, amyl, n-hexyl, i-hexyl, n-octyl, decyl, dodecyl, octadecyl, 2-ethylhexyl, phenyl, butylphenyl, cyclohexyl, methylcyclopentyl, propenyl, or butenyl. The number of carbon atoms in each R group in the above formula is generally about 3 or more, about 4 or more, about 6 or more, or about 8 or more. Each R group may have an average of 6 to 10 carbon atoms, preferably 8 to 10 carbon atoms. Preferably, each R may be a linear or branched C8 or 2-ethylhexyl group, a C3 or isopropyl group, and / or a C4 or isobutyl group. In Formula I, A is a metal, such as aluminum, lead, tin, molybdenum, manganese, nickel, copper, titanium, zirconium, zinc, or a combination thereof, preferably A is zinc. When a metal dihydrocarbyl dithiophosphate compound has the structure shown in Formula I and A is zinc, the compound may have about 6 to about 9 weight percent phosphorus and about 7 to about 9 weight percent zinc, and a zinc-to-phosphorus ratio of about 1.0 to about 1.5. In some approaches or embodiments, it is understood in the art that a more precise representation of the sulfur-zinc coordination configuration may be represented by the symmetric configuration shown below, having the chemical structure of Formula II, which may be used herein as interchangeable with Formula I shown above. It is also understood that the structures shown in formulas I and II can exist as monomers, dimers, trimers, or oligomers (e.g., tetramers).

[0070] [ka]

[0071] Dihydrocarbyl dithiophosphate metal salts can be prepared according to known techniques, usually by first reacting one or more alcohols or phenols with P2S5 to form dihydrocarbyl dithiophosphoric acid (DDPA), and then neutralizing the formed DDPA with a metal compound such as zinc oxide. For example, DDPA can be produced by reacting a mixture of alcohols containing a suitable amount of primary alcohol (and, if necessary, a suitable blend of primary and secondary alcohols) with P2S5. In this case, the DDPA contains alkyl groups mainly derived from the primary alcohol, or from both primary and secondary alcohols, as necessary to satisfy the required primary alcohol content in the final product. Alternatively, multiple DDPAs can be prepared, with the alkyl groups on one DDPA being entirely derived from a secondary alcohol and the alkyl groups on another DDPA being entirely derived from a primary alcohol. The DDPAs are then blended together to form a mixture of DDPAs having alkyl groups that satisfy the above primary alcohol content.

[0072] Base oil or base oil blend: The base oils used in the crankcase lubricant compositions described herein, particularly heavy-duty crankcase lubricant compositions, may be oils of lubrication viscosity and can be selected from any of the API Group I to V base oils specified in the American Petroleum Institute (API) Base Oil Interchangeability Guidelines. Heavy-duty crankcase lubricants may have a kV100 (ASTM D445) of about 9 to about 20 cSt. In some cases, even lower viscosities are targeted, and crankcase lubricants, particularly heavy-duty crankcase lubricants, have a kV100 (ASTM D445) of about 5 to about 9 cSt. The five base oil groups are generally shown in Table 1 below.

[0073] [Table 1]

[0074] Groups I, II, and III are mineral oil process raw materials. Group IV base oils contain true synthetic molecular species produced by the polymerization of olefinic unsaturated hydrocarbons. Many Group V base oils are also true synthetic products and may include diesters, polyol esters, polyalkylene glycols, alkylated aromatics, polyphosphate esters, polyvinyl ethers, and / or polyphenyl ethers, but may also be natural oils such as vegetable oils. It should be noted that Group III base oils are derived from mineral oils, but due to the rigorous processing these fluids undergo, their physical properties become very similar to those of some true synthetic oils such as PAO. Therefore, oils derived from Group III base oils can be referred to as synthetic fluids in industry. Group II+ may include high viscosity index Group II.

[0075] The base oil blends used in the disclosed lubricating oil compositions may be mineral oils, animal oils, vegetable oils, synthetic oils, synthetic oil blends, or mixtures thereof. Suitable oils may be derived from hydrocracking, hydrotapping, hydrofinishing, unrefined oils, refined oils, and re-refined oils, as well as mixtures thereof.

[0076] Unrefined oils are derived from natural, mineral, or synthetic sources that undergo little to no further refining. Refined oils are similar to unrefined oils except that they have been processed in one or more refining steps that may result in an improvement in one or more properties. Examples of preferred refining techniques include solvent extraction, secondary distillation, acid or base extraction, filtration, and osmosis. Oils refined to a quality suitable for consumption may or may not be useful. Edible oils are sometimes called white oils. In some embodiments, lubricating oil compositions do not contain edible oils or white oils.

[0077] Refined oil is also known as recycled oil or reprocessed oil. These oils are obtained in the same way as refined oil using the same or similar processes. Often, these oils are further treated by techniques that target the removal of spent additives and oil degradation products.

[0078] Mineral oils may include oils obtained by drilling, or from plants and animals, or any mixture thereof. For example, such oils may include, but are not limited to, castor oil, lard, olive oil, peanut oil, corn oil, soybean oil, and linseed oil, as well as mineral lubricants, such as liquid petroleum, and paraffinic, naphthenic, or mixed paraffinic-naphthenic type solvent-treated or acid-treated mineral lubricants. Such oils may be partially or completely hydrogenated if desired. Oils derived from coal or shale may also be useful.

[0079] Useful synthetic lubricants include hydrocarbon oils, such as polymerized, oligomerized, or interpolymerized olefins (e.g., polybutylene, polypropylene, propylene isobutylene copolymer); trimers or oligomers of poly(1-hexene), poly(1-octene), and 1-decene, such as poly(1-decene) (such materials are often referred to as α-olefins), and mixtures thereof; alkylbenzenes (e.g., dodecylbenzene, tetradecylbenzene, dinonylbenzene, di-(2-ethylhexyl)-benzene); polyphenyls (e.g., biphenyl, terphenyl, alkylated polyphenyls); diphenylalkanes, alkylated diphenylalkanes, alkylated diphenyl ethers, and alkylated diphenyl sulfides, as well as their derivatives, analogs, and homologs, or mixtures thereof. Polyalphaolefins are typically hydrogenated materials.

[0080] Other synthetic lubricants include polyol esters, diesters, liquid esters of phosphorus-containing acids (e.g., tricresyl phosphate, trioctyl phosphate, and diethyl esters of decanephosphonic acid), or polymeric tetrahydrofurans. Synthetic oils can be produced by the Fischer-Tropsch reaction and are typically hydrogenated isomerized Fischer-Tropsch hydrocarbons or waxes. In one embodiment, the oil may be prepared by the Fischer-Tropsch gas-liquid synthesis procedure and other gas-liquid oils.

[0081] In another embodiment, the main amount of base oil contained in the lubricating composition may be selected from the group consisting of Group I, Group II, Group III, Group IV, Group V, and any combination of two or more of the aforementioned, but the main amount of base oil is other than the base oil resulting from the provision of additive components or viscosity index modifiers in the composition.

[0082] The amount of lubricating viscosity oil present may be the remainder after subtracting the total amount of performance additives, including viscosity index improvers and / or pour point depressants and / or other top-treatment additives, from 100% by weight. For example, the amount of lubricating viscosity oil that may be present in the final fluid may be the majority amount, e.g., more than about 50% by weight, more than about 60% by weight, more than about 70% by weight, more than about 80% by weight, more than about 85% by weight, or more than about 90% by weight.

[0083] In some approaches or embodiments, the base oil systems of this specification may comprise one or more base oils from groups I to V and have a KV100 of about 2 to about 20 cSt, in other approaches about 2 to about 10 cSt, about 2.5 to about 6 cSt, in yet another approach about 2.5 to about 3.5 cSt, and in yet another approach about 2.5 to about 4.5 cSt. As used herein, the terms “oil composition,” “lubricating composition,” “lubricating oil composition,” “lubricating oil,” “lubricant composition,” “completely formulated lubricant composition,” “lubricant,” and “lubricating and cooling fluid” are considered synonymous and fully interchangeable terms referring to a finished lubricating product comprising a majority amount of base oil components and small amounts of detergents and other optional components.

[0084] Optional additives: The lubricating oil compositions described herein, in particular heavy-duty lubricating oil compositions, may also contain several optional additives, in combination with the detergent and dispersant systems discussed above, as necessary to meet performance requirements. These optional additives are described in the following paragraphs.

[0085] Anti-wear agents: The lubricating oil compositions herein may also optionally contain additional anti-wear agents. Examples of suitable anti-wear agents include, but are not limited to, metal thiophosphates; metal dialkyldithiophosphates; phosphate esters or salts thereof; phosphate esters; phosphites; phosphorus-containing carboxylic acid esters, ethers, or amides; sulfurized olefins; thiocarbamate-containing compounds such as thiocarbamate esters, alkylene-linked thiocarbamates, and bis(S-alkyldithiocarbamyl) disulfide; and mixtures thereof. A suitable anti-wear agent may be molybdenum dithiocarbamate. Phosphorus-containing anti-wear agents are fully described in European Patent No. 612839. The metal in the dialkyldithiophosphate salt may be alkali metals, alkaline earth metals, aluminum, lead, tin, molybdenum, manganese, nickel, copper, titanium, or zinc. A useful anti-wear agent may be zinc dialkyldithiophosphate.

[0086] Further examples of suitable additional abrasion resistant agents include titanium compounds, tartarates, tartrimides, oil-soluble amine salts of phosphorus compounds, sulfurized olefins, phosphites (such as dibutyl phosphite), phosphonates, thiocarbamate-containing compounds, such as thiocarbamate esters, thiocarbamate amides, thiocarbamine ethers, alkylene-linked thiocarbamates, and bis(S-alkyldithiocarbamyl) disulfides. Tartarates or tartrimides may contain alkyl-ester groups, and the total number of carbon atoms on the alkyl group may be at least 8. In one embodiment, the abrasion resistant agent may include citrates.

[0087] Additional anti-wear agents may be present in amounts ranging from about 0% to about 15% by weight, or about 0.01% to about 10% by weight, or about 0.05% to about 5% by weight, or about 0.1% to about 3% by weight of the lubricating oil composition.

[0088] Boron-containing compounds: The lubricating oil compositions herein may optionally contain one or more boron-containing compounds. Examples of boron-containing compounds include borate esters, fatty borooxide amines, borooxide epoxides, borooxide detergents, dispersed sodium or potassium hydrated borate, and borooxide dispersants such as succinimide borooxide dispersants, as disclosed in U.S. Patent No. 5,883,057. If present, boron-containing compounds may be used in amounts sufficient to provide a maximum of about 8% by weight, about 0.01% to about 7% by weight, about 0.05% to about 5% by weight, or about 0.1% to about 3% by weight of the lubricating oil composition.

[0089] Additional detergents: The lubricating oil composition may optionally further contain one or more neutral detergents, low-basic detergents, or over-basic detergents, and mixtures thereof. Suitable detergent substrates include phenates, sulfur-containing phenates, sulfonates, calixalates, salixalates, salicylates, carboxylic acids, phosphoric acids, mono- and / or di-thiophosphates, alkylphenols, sulfur-linked alkylphenol compounds, or methylene-crosslinked phenols. Suitable detergents and methods for preparing them are described in detail in numerous patent publications, including U.S. Patent No. 7,732,390 and the references cited therein.

[0090] The detergent substrate is not limited, but may be chlorided with alkali metals or alkaline earth metals such as calcium, magnesium, potassium, sodium, lithium, barium, or mixtures thereof. In some embodiments, the detergent does not contain barium. In some embodiments, the detergent may contain trace amounts of other metals such as magnesium or calcium in amounts such as 50 ppm or less, 40 ppm or less, 30 ppm or less, 20 ppm or less, or 10 ppm or less. Suitable detergents include alkali metal or alkaline earth metal salts of petroleum sulfonic acid and long-chain mono- or di-alkylarylsulfonic acid whose aryl group is benzyl, tolyl, or xylyl. Examples of suitable cleaning agents include, but are not limited to, calcium carbonate, sulfur-containing calcium carbonate, calcium sulfonate, calcium calixalate, calcium salixalate, calcium salicylate, calcium carboxylate, calcium phosphate, mono- and / or di-thiophosphate calcium, calcium alkylphenol, calcium sulfur-linked alkylphenol compounds, calcium methylene crosslinked phenol, magnesium carbonate, sulfur-containing magnesium carbonate, magnesium sulfonate, magnesium calixalate, magnesium salixalate, magnesium salicylate, magnesium carboxylate, magnesium phosphate, mono- and / or di-thiophosphate magnesium, magnesium alkylphenol, magnesium sulfur-linked alkylphenol compounds, magnesium methylene crosslinked phenol, sodium carbonate, sulfur-containing sodium carbonate, sodium sulfonate, sodium calixalate, sodium salixalate, sodium salicylate, sodium carboxylate, sodium phosphate, mono- and / or di-thiophosphate sodium, sodium alkylphenol, sodium sulfur-linked alkylphenol compounds, or sodium methylene crosslinked phenol.

[0091] Overbasic detergent additives are well known in the art and may be alkaline or alkaline earth metal overbasic detergent additives. Such detergent additives can be prepared by reacting a metal oxide or metal hydroxide with a substrate and carbon dioxide gas. The substrate is typically an acid, such as an aliphatic-substituted sulfonic acid, an aliphatic-substituted carboxylic acid, or an aliphatic-substituted phenol.

[0092] The overbasic detergent in the lubricating oil composition may have a total base number (TBN) of approximately 200 mg KOH / g or more, or, as further examples, approximately 250 mg KOH / g or more, or approximately 350 mg KOH / g or more, or approximately 375 mg KOH / g or more, or approximately 400 mg KOH / g or more. The TBN is measured by the method of ASTM D2896.

[0093] Suitable examples of perbasic detergents include, but are not limited to, perbasic calcium phenate, perbasic calcium sulfur-containing phenate, perbasic calcium sulfonate, perbasic calcium calixalate, perbasic calcium salixalate, perbasic calcium salicylate, perbasic calcium carboxylic acid, perbasic calcium phosphate, perbasic calcium mono- and / or di-thiophosphate, perbasic calcium alkylphenol, perbasic calcium sulfur-bonded alkylphenol compound, perbasic calcium methylene crosslinked phenol, perbasic magnesium phenate, perbasic magnesium sulfur-containing phenate, perbasic magnesium sulfonate, perbasic magnesium calixalate, perbasic magnesium salixalate, perbasic magnesium salicylate, perbasic magnesium carboxylic acid, perbasic magnesium phosphate, perbasic magnesium mono- and / or di-thiophosphate, perbasic magnesium alkylphenol, perbasic magnesium sulfur-bonded alkylphenol compound, or perbasic magnesium methylene crosslinked phenol.

[0094] Overbasic phenate calcium detergents, when measured according to ASTM D2896, have a total base number of at least about 150 mg KOH / g, at least about 225 mg KOH / g, at least about 225 mg KOH to about 400 mg KOH / g, at least about 225 mg KOH to about 350 mg KOH / g, or about 230 mg KOH to about 350 mg KOH / g. When such detergent compositions are formed in an inert diluent, such as process oil, usually mineral oil, the total base number reflects the basicity of the overall composition, including the diluent and any other materials that may be present in the detergent composition (e.g., accelerators).

[0095] The overbasic detergent may have a metal-to-substrate ratio ranging from 1.1:1, 2:1, 4:1, 5:1, 7:1, or 10:1. In some embodiments, the detergent is effective in reducing or preventing rust in the engine or other automotive parts such as the transmission or gears. The detergent may be present in the lubricating composition in amounts of about 0% to about 10% by weight, or about 0.1% to about 8% by weight, or about 1% to about 4% by weight, or more than about 4% to about 8% by weight.

[0096] Extreme pressure agents: The lubricating oil compositions of this specification may also optionally contain one or more extreme pressure agents. Oil-soluble extreme pressure (EP) agents include sulfur and chlorosulfur-containing EP agents, chlorinated hydrocarbon EP agents, and phosphorus EP agents. Examples of such EP agents include chlorinated waxes; organic sulfides and polysulfides such as dibenzyl disulfide, bis(chlorobenzyl) disulfide, dibutyltetrasulfide, methyl sulfide esters of oleic acid, alkylphenol sulfides, dipentene sulfides, terpenes sulfides, and Diels-Alder sulfide adducts; phosphorus sulfide hydrocarbons such as reaction products of phosphorus sulfide with terpentine or methyl oleate; phosphate esters such as dihydrocarbyl and trihydrocarbyl phosphite, e.g., dibutyl phosphite, diheptyl phosphite, dicyclohexyl phosphite, and pentylphenyl phosphite; dipentylphenyl phosphite, tridecyl phosphite, distearyl phosphite, and polypropylene-substituted phenyl phosphite; metal thiocarbamates such as zinc dioctyl dithiocarbamate and barium heptylphenol dioate; amine salts of alkyl and dialkyl phosphates, e.g., amine salts of reaction products of dialkyldithiophosphate and propylene oxide; and mixtures thereof.

[0097] Friction modifiers: The lubricating oil compositions herein may also optionally contain one or more friction modifiers. Suitable friction modifiers may include metal-containing and metal-free friction modifiers, but are not limited to imidazolines, amides, amines, succinimides, alkoxylated amines, alkoxylated etheramines, amine oxides, amidoamines, nitriles, betaines, quaternary amines, imines, amine salts, aminoguanidines, alkanolamides, phosphonates, metal-containing compounds, glycerol esters, sulfurized fatty compounds and olefins, sunflower oil, other naturally occurring vegetable or animal oils, dicarboxylic acid esters, esters or partial esters of polyols with one or more aliphatic or aromatic carboxylic acids, and the like.

[0098] Suitable friction modifiers may contain hydrocarbyl groups selected from linear, branched, or aromatic hydrocarbyl groups, or mixtures thereof, and may be saturated or unsaturated. Hydrocarbyl groups may consist of carbon and a heteroatom such as hydrogen or sulfur or oxygen. Hydrocarbyl groups may range from about 12 to about 25 carbon atoms. In some embodiments, the friction modifier may be a long-chain fatty acid ester. In other embodiments, the long-chain fatty acid ester may be a mono-ester, di-ester, or (tri)glyceride. The friction modifier may be a long-chain fatty amide, a long-chain fatty ester, a long-chain fatty epoxide derivative, or a long-chain imidazoline.

[0099] Other suitable friction modifiers may include organic, ashless (metal-free), and nitrogen-free organic friction modifiers. Such friction modifiers may contain esters formed by reacting a carboxylic acid and an anhydride with an alkanol, and may generally contain polar end groups (e.g., carboxyl or hydroxyl) covalently bonded to a lipophilic hydrocarbon chain. An example of an organic ashless nitrogen-free friction modifier is generally known as glycerol monooleate (GMO), which may contain mono-, di-, and tri-esters of oleic acid. Other suitable friction modifiers are described in their entirety in U.S. Patent No. 6,723,685, which is incorporated herein by reference.

[0100] Amineral friction modifiers may include amines or polyamines. Such compounds may have linear hydrocarbyl groups that are either saturated or unsaturated, or a mixture thereof, and may contain about 12 to about 25 carbon atoms. Further examples of suitable friction modifiers include alkoxylated amines and alkoxylated etheramines. Such compounds may have linear hydrocarbyl groups that are either saturated or unsaturated, or a mixture thereof. These may contain about 12 to about 25 carbon atoms. Examples include ethoxylated amines and ethoxylated etheramines.

[0101] Amines and amides may be used on their own or as adducts or reaction products with boron compounds such as boron oxide, boron halides, metaborates, boric acid, or mono-, di-, or tri-alkylborates. Other suitable friction modifiers are described in whole in U.S. Patent No. 6,300,291, which is incorporated herein by reference.

[0102] The friction modifier may be optionally present in a range such as approximately 0% to 10% by weight, approximately 0.01% to 8% by weight, or approximately 0.1% to 4% by weight.

[0103] Transition metal-containing compounds: In another embodiment, the oil-soluble compound may be a transition metal-containing compound or a metalloid. Examples of transition metals include, but are not limited to, titanium, vanadium, copper, zinc, zirconium, molybdenum, tantalum, and tungsten. Examples of preferred metalloids include, but are not limited to, boron, silicon, antimony, and tellurium.

[0104] In some embodiments, the oil-soluble transition metal-containing compound may function as an anti-wear agent, friction modifier, antioxidant, adhesion control additive, or two or more of these functions. In some embodiments, the oil-soluble transition metal-containing compound may be an oil-soluble titanium compound such as titanium(IV) alkoxide. Among the titanium-containing compounds that may be used in or for use in the preparation of oil-soluble materials in the art of the present disclosure are various Ti(IV) compounds such as titanium(IV) oxide; titanium(IV) sulfide; titanium(IV) nitrate; titanium(IV) alkoxides, e.g., titanium methoxide, titanium ethoxide, titanium propoxide, titanium isopropoxide, titanium butoxide, titanium 2-ethylhexoxide; and other titanium compounds or complexes, e.g., but not limited to titanium phenate; titanium carboxylates, e.g., titanium(IV) 2-ethyl-1,3-hexanedioate or titanium citrate or titanium oleate; and titanium(IV) (triethanolamine) isopropoxide. Other forms of titanium included within the disclosed technology include titanium phosphates such as titanium dithiophosphates (e.g., dialkyldithiophosphates) and titanium sulfonates (e.g., alkylbenzene sulfonates), or reaction products of titanium compounds that form salts, such as oil-soluble salts, with various acidic materials. Therefore, titanium compounds can be derived, in particular, from organic acids, alcohols, and glycols. Ti compounds may also exist in dimer or oligomeric forms containing a Ti-O-Ti structure. Such titanium materials are commercially available or readily prepared by appropriate synthetic techniques evident to those skilled in the art. Depending on the specific compound, they may exist as solids or liquids at room temperature. They may also be provided in solution form in a suitable inert solvent.

[0105] In one embodiment, titanium may be supplied as a Ti-modified dispersant, such as a succinimide dispersant. Such a material may be prepared by forming a titanium mixed anhydride between a titanium alkoxide and a hydrocarbyl-substituted succinic anhydride, such as alkenyl-(or alkyl) succinic anhydride. The resulting titanate-succinate intermediate may be used directly or reacted with any of several materials, such as (a) a polyamine-based succinimide / amide dispersant having a free, condensable -NH functional group; (b) a component of a polyamine-based succinimide / amide dispersant, i.e., alkenyl-(or alkyl) succinic anhydride and a polyamine; or (c) a hydroxy-containing polyester dispersant prepared by the reaction of substituted succinic anhydride with a polyol, amino alcohol, polyamine, or a mixture thereof. Alternatively, the titanate-succinate intermediate may be reacted with other agents such as alcohols, amino alcohols, ether alcohols, polyether alcohols or polyols, or fatty acids, and the product may be used directly to impart Ti to the lubricant or further reacted with a succinic acid dispersant as described above. As an example, to provide a titanium-modified dispersant or intermediate, 1 part (mol) of tetraisopropyl titanate may be reacted with about 2 parts (mol) of polyisobutene-substituted succinic anhydride at 140-150°C for 5-6 hours. The resulting material (30 g) may be further reacted at 150°C for 1.5 hours with a succinimide dispersant from a mixture of polyisobutene-substituted succinic anhydride and polyethylene polyamine (127 g + diluent oil) to produce a titanium-modified succinimide dispersant.

[0106] Another titanium-containing compound is titanium alkoxide and C6-C6 25 It may be a reaction product with a carboxylic acid. The reaction product is given by the following formula:

[0107] [ka] It can be represented by (wherein n is an integer selected from 2, 3, and 4, and R is a hydrocarbyl group containing about 5 to about 24 carbon atoms) or by the following formula:

[0108] [ka] (wherein m+n=4, n is in the range of 1 to 3, R4 is an alkyl moiety having 1 to 8 carbon atoms, R1 is selected from hydrocarbyl groups containing approximately 6 to 25 carbon atoms, and R2 and R3 are the same or different and selected from hydrocarbyl groups containing 1 to 6 carbon atoms) or the titanium compound may be represented by the following formula:

[0109] [ka] (In the formula, x is in the range of 0 to 3, R1 is selected from hydrocarbyl groups containing approximately 6 to 25 carbon atoms, R2 and R3 are the same or different and selected from hydrocarbyl groups containing approximately 1 to 6 carbon atoms, and R4 is H, C6 to C) 25 It can be represented by (selected from the group consisting of any of the carboxylic acid moieties).

[0110] Suitable carboxylic acids include, but are not limited to, caproic acid, caprylic acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, oleic acid, erucic acid, linoleic acid, linolenic acid, cyclohexanecarboxylic acid, phenylacetic acid, benzoic acid, and neodecanoic acid.

[0111] In one embodiment, the oil-soluble titanium compound may be present in the lubricating oil composition in an amount to provide about 0 to about 3000 ppm by weight of titanium, or 25 to about 1500 ppm by weight of titanium, or about 35 ppm to about 500 ppm by weight of titanium, or about 50 ppm to about 300 ppm by weight of titanium.

[0112] Viscosity Index Modifiers: The lubricating oil compositions of this specification may also optionally contain one or more viscosity index modifiers. Suitable viscosity index modifiers include polyolefins, olefin copolymers, ethylene / propylene copolymers, polyisobutene, styrene-isoprene polymers, styrene / maleate copolymers, styrene-butadiene copolymers, styrene-isoprene polymers, alpha-olefin maleic anhydride copolymers, polymethacrylates, polyacrylates, polyalkylstyrenes, hydrated alkenylaryl conjugated diene copolymers, or mixtures thereof. Viscosity index modifiers may include star polymers, but a preferred example is described in U.S. Patent Application Publication No. 20120101017(A1).

[0113] The lubricating oil compositions of this specification may optionally contain one or more dispersant viscosity index modifiers in addition to, or instead of, a viscosity index modifier. Suitable viscosity index modifiers include functionalized polyolefins, such as ethylene-propylene copolymers functionalized with the reaction product of an acylating agent (such as maleic anhydride) and an amine, amine-functionalized polymethacrylates, or esterified maleic anhydride-styrene copolymers reacted with an amine.

[0114] The total amount of viscosity index improvers and / or dispersible viscosity index improvers may be about 0% to about 20% by weight, about 0.1% to about 15% by weight, about 0.1% to about 12% by weight, or about 0.5% to about 10% by weight of the lubricating oil composition.

[0115] Other optional additives: Other additives may be selected to perform one or more functions required of the lubricating fluid. Furthermore, one or more of the aforementioned additives may be polyfunctional and may provide functions in addition to those described herein, or other functions.

[0116] Lubricant compositions according to this disclosure may optionally include other performance additives. These other performance additives may be additions to the specific additives of this disclosure and / or may include one or more of the following: metal deactivators, viscosity index modifiers, detergents, ashless TBN boosters, friction modifiers, anti-wear agents, corrosion inhibitors, rust inhibitors, dispersants, dispersant viscosity index modifiers, extreme pressure agents, antioxidants, foam inhibitors, deemulsifiers, emulsifiers, pour point depressants, seal swelling agents, and mixtures thereof. Typically, a complete lubricant composition will contain one or more of these performance additives.

[0117] Suitable metal deactivators include derivatives of benzotriazole (typically toltriazole), dimercaptothiadiazole derivatives, 1,2,4-triazole, benzimidazole, 2-alkyldithiobenzimidazole, or 2-alkyldithiobenzothiazole; foam inhibitors comprising copolymers of ethyl acrylate, 2-ethylhexyl acrylate, and optionally vinyl acetate; demulsifiers comprising trialkyl phosphates, polyethylene glycol, polyethylene oxide, polypropylene oxide, and (ethylene oxide-propylene oxide) polymers; and pour point depressants comprising esters of maleate-styrene anhydride, polymethacrylate, polyacrylate, or polyacrylamide.

[0118] Suitable foam inhibitors include silicon-based compounds such as siloxanes.

[0119] Suitable pour point depressants may include polymethyl methacrylate or mixtures thereof. The pour point depressant may be present in an amount sufficient to provide about 0% to about 1% by weight, about 0.01% to about 0.5% by weight, or about 0.02% to about 0.04% by weight, based on the final weight of the lubricating oil composition.

[0120] Suitable rust inhibitors may be a single compound or a mixture of compounds having properties that inhibit corrosion of iron metal surfaces. Non-limiting examples of rust inhibitors useful herein include oil-soluble high molecular weight organic acids such as 2-ethylhexanoic acid, lauric acid, myristic acid, palmitic acid, oleic acid, linoleic acid, linolenic acid, behenic acid, and cerotic acid, as well as oil-soluble polycarboxylic acids including dimeric and trimeric acids such as those derived from tall oil fatty acids, oleic acid, and linoleic acid. Other suitable corrosion inhibitors include long-chain alpha- and omega-dicarboxylic acids in the molecular weight range of about 600 to about 3000, and alkenyl succinates containing about 10 or more carbon atoms in the alkenyl group, such as tetrapropenyl succinic acid, tetradecenyl succinic acid, and hexadecenyl succinic acid. Another useful type of acidic corrosion inhibitor is a semi-ester of alkenyl succinic acid having about 8 to about 24 carbon atoms in the alkenyl group with an alcohol such as polyglycol. The corresponding semiamides of such alkenyl succinic acids are also useful. Useful rust inhibitors are high molecular weight organic acids.

[0121] If present, rust inhibitors may be used in an amount sufficient to provide about 0% to about 5% by weight, about 0.01% to about 3% by weight, or about 0.1% to about 2% by weight, based on the final weight of the lubricating oil composition.

[0122] Generally speaking, preferred lubricants containing cleaning metals as used herein may contain additive components within the range listed in the table below.

[0123] [Table 2]

[0124] The percentages of each component listed above represent the weight percentage of each component based on the weight of the final lubricating oil composition. The remainder of the lubricating oil composition consists of one or more base oils. The additives used in formulating the compositions described herein may be blended with the base oils individually or in various partial combinations. However, it may be preferable to blend all the components simultaneously using an additive concentrate (i.e., the additives and a diluent such as a hydrocarbon solvent). A complete lubricant conventionally contains an additive package, referred herein as a dispersant / inhibitor package or DI package, which provides the properties required in the formulation.

[0125] definition For the purposes of this disclosure, chemical elements are identified according to the Periodic Table of the Elements, CAS version, Handbook of Chemistry and Physics, 75th Ed. In addition, the general principles of organic chemistry are described in "Organic Chemistry," Thomas Sorrell, University Science Books, Sausolito: 1999, and "March's Advanced Organic Chemistry," 5th Ed., Ed.: Smith, MB and March, J., John Wiley & Sons, New York: 2001, the entire contents of which are incorporated herein by reference.

[0126] As described herein, compounds may be optionally substituted with one or more substituents, as generally illustrated above or as illustrated by specific classes, subclasses, and species of the Disclosure.

[0127] Unless otherwise clearly indicated, the term “major amount” is understood to mean an amount of 50 weight percent or more, for example, about 80 to about 98 weight percent, of the total weight of the composition. Similarly, as used herein, the term “minor amount” is understood to mean an amount of less than 50 weight percent of the total weight of the composition.

[0128] As used herein, the terms "hydrocarbyl group" or "hydrocarbyl" are used in their ordinary sense as is well known to those skilled in the art. Specifically, it refers to a group having carbon atoms directly bonded to the rest of the molecule and having primarily hydrocarbon properties. Examples of hydrocarbyl groups include (1) hydrocarbon substituents, i.e., aliphatic (e.g., alkyl or alkenyl) substituents, alicyclic (e.g., cycloalkyl, cycloalkenyl) substituents, and aromatic substitutions, aliphatic substitutions, and alicyclic-substituted aromatic substituents, as well as cyclic substituents where the ring is completed via another part of the molecule (e.g., two substituents together form an alicyclic radical); (2) substituted hydrocarbon substituents, i.e., substituents containing non-hydrocarbon groups that do not primarily alter the hydrocarbon substituent in the context of this disclosure (e.g., halo (especially chloro and fluoro), hydroxy, alkoxy, mercapto, alkylmercapto, nitro, nitroso, amino, alkylamino, and sulfoxy); and (3) heterosubstituted substituents, i.e., substituents that primarily possess hydrocarbon properties in the context of this disclosure, while containing non-carbon elements in the ring or chain, or otherwise composed of carbon atoms. Heteroatoms include sulfur, oxygen, and nitrogen, and encompass substituents such as pyridyl, furyl, thienyl, and imidazolyl. Generally, there are two or fewer non-hydrocarbon substituents for every 10 carbon atoms in the hydrocarbyl group, or in further examples, just one, and in some embodiments, there may be no non-hydrocarbon substituents in the hydrocarbyl group.

[0129] As used herein, the term “aliphatic” encompasses the terms alkyl, alkenyl, and alkynyl, each of which is optionally substituted as described below.

[0130] As used herein, the “alkyl” group refers to a saturated aliphatic hydrocarbon group containing 1 to 12 carbon atoms (e.g., 1 to 8, 1 to 6, or 1 to 4). Alkyl groups may be linear or branched. Examples of alkyl groups, but not limited to, include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, n-heptyl, or 2-ethylhexyl. Alkyl groups are defined as groups with one or more substituents, e.g., halo, phospho, alicyclic [e.g., cycloalkyl or cycloalkenyl], heteroalicyclic [e.g., heterocycloalkyl or heterocycloalkenyl], aryl, heteroaryl, alkoxy, aroyl, heteroaloyl, acyl [e.g., (aliphatic) carbonyl, (alicyclic) carbonyl, or (heteroalicyclic) carbonyl], nitro, cyano, amide [e.g., (cycloalkylalkyl)carbonylamino, arylcarbonylamino, aralkylcarbonylamino, (heterocycloalkyl)carbonylamino, (heterocycloalkylalkyl)carbonylamino, heteroarylcarbonylamino, heteroaralkylcarbonylamino It may be substituted (i.e., optionally substituted) with hydroxylaminocarbonyl, cycloalkylaminocarbonyl, heterocycloalkylaminocarbonyl, arylaminocarbonyl, or heteroarylaminocarbonyl, amino, [e.g., aliphatic amino, alicyclic amino, or heteroalicyclic amino], sulfonyl [e.g., aliphatic-SO2-], sulfinyl, sulfanyl, sulfoxy, urea, thiourea, sulfamoyl, sulfamide, oxo, carboxy, carbamoyl, alicyclic oxy, heterocycloaliphatic oxy, aryl oxy, heteroaryl oxy, aralkyl oxy, heteroaryl alkoxy, alkoxycarbonyl, alkylcarbonyl oxy, or hydroxy.Some examples of substituted alkyls, though not limited to them, include carboxyalkyls (e.g., HOOC-alkyls, alkoxycarbonylalkyls, and alkylcarbonyloxyalkyls), cyanoalkyls, hydroxyalkyls, alkoxyalkyls, acylalkyls, aralkyls, (alkoxyaryl)alkyls, (sulfonylamino)alkyls (e.g., (alkyl-SO2-amino)alkyls), aminoalkyls, amidealkyls, (alicyclic)alkyls, or haloalkyls.

[0131] As used herein, the “alkenyl” group refers to an aliphatic carbon group containing 2 to 8 (e.g., 2 to 12, 2 to 6, or 2 to 4) carbon atoms and at least one double bond. Like alkyl groups, alkenyl groups can be linear or branched. Examples of alkenyl groups, but not limited to, include allyl, isoprenyl, 2-butenyl, and 2-hexenyl. The alkenyl group may have one or more substituents, e.g., halo, phospho, alicyclic [e.g., cycloalkyl or cycloalkenyl], heteroalicyclic [e.g., heterocycloalkyl or heterocycloalkenyl], aryl, heteroaryl, alkoxy, aroyl, heteroaloyl, acyl [e.g., (aliphatic) carbonyl, (alicyclic) carbonyl, or (heteroalicyclic) carbonyl], nitro, cyano, amide [e.g., (cycloalkylalkyl)carbonylamino, arylcarbonylamino, aralkylcarbonylamino, (heterocycloalkyl)carbonylamino, (heterocycloalkylalkyl)carbonylamino, heteroarylcarbonylamino, heteroaralkylcarbonylaminoalkylaminocarbon These can be optionally substituted with [nyl, cycloalkylaminocarbonyl, heterocycloalkylaminocarbonyl, arylaminocarbonyl, or heteroarylaminocarbonyl], amino [e.g., aliphatic amino, alicyclic amino, heteroalicyclic amino, or aliphatic sulfonylamino], sulfonyl [e.g., alkyl-SO2-, alicyclic-SO2-, or aryl-SO2-], sulfinyl, sulfanyl, sulfoxy, urea, thiourea, sulfamoyl, sulfamide, oxo, carboxy, carbamoyl, alicyclic oxy, heteroalicyclic oxy, aryl oxy, heteroaryl oxy, aralkyl oxy, heteroaralkoxy, alkoxycarbonyl, alkylcarbonyl oxy, or hydroxy. Some examples of substituted alkenyls, though not limited to them, include cyanoalkenyls, alkoxyalkenyls, acylalkenyls, hydroxyalkenyls, aralkenyls, (alkoxyaryl)alkenyls, (sulfonylamino)alkenyls (e.g., (alkyl-SO2-amino)alkenyls), aminoalkenyls, amidealkenyls, (alicyclic)alkenyls, or haloalkenyls.

[0132] As used herein, the “alkynyl” group refers to an aliphatic carbon group containing 2 to 8 carbon atoms (e.g., 2 to 12, 2 to 6, or 2 to 4) and having at least one triple bond. The alkynyl group may be linear or branched. Examples of alkynyl groups include, but are not limited to, propargyl and butynyl. The alkynyl group is a substituent of one or more types, such as aroyl, heteroaloyl, alkoxy, cycloalkyloxy, heterocycloalkyloxy, aryloxy, heteroaryloxy, aralkyloxy, nitro, carboxy, cyano, halo, hydroxy, sulfo, mercapto, sulfanyl [e.g., aliphatic sulfanyl or alicyclic sulfanyl], sulfinyl [e.g., aliphatic sulfinyl or alicyclic finyl], sulfonyl [e.g., aliphatic-SO2-, aliphatic-amino-SO2-, or alicyclic-SO2-], amide [e.g., aminocarbonyl, alkylaminocarbonyl, alkylcarbonylamino, cycloalkylaminocarbonyl, heterocycloalkylaminocarbonyl, cycloalkylcarbonylamino, aryl] The aminocarbonyl, arylcarbonylamino, aralkylcarbonylamino, (heterocycloalkyl)carbonylamino, (cycloalkylalkyl)carbonylamino, heteroaralkylcarbonylamino, heteroarylcarbonylamino, or heteroarylaminocarbonyl], urea, thiourea, sulfamoyl, sulfamide, alkoxycarbonyl, alkylcarbonyloxy, alicyclic, heteroalicyclic, aryl, heteroaryl, acyl [e.g., (alicyclic)carbonyl or (heteroalicyclic)carbonyl], amino [e.g., aliphatic amino], sulfoxy, oxo, carboxy, carbamoyl, (alicyclic)oxy, (heteroalicyclic)oxy, or (heteroaryl)alkoxy can be optionally substituted.

[0133] As used herein, the "amino" group means -NR X R Y It refers to, and in the formula, R X and R YEach of these is independently hydrogen, alkyl, cycloalkyl, (cycloalkyl)alkyl, aryl, aralkyl, heterocycloalkyl, (heterocycloalkyl)alkyl, heteroaryl, carboxy, sulfanyl, sulfinyl, sulfonyl, (alkyl)carbonyl, (cycloalkyl)carbonyl, ((cycloalkyl)alkyl)carbonyl, arylcarbonyl, (aralkyl)carbonyl, (heterocycloalkyl)carbonyl, ((heterocycloalkyl)alkyl)carbonyl, (heteroaryl)carbonyl, or (heteroaralkyl)carbonyl, each of which is defined herein and optionally substituted. Examples of amino groups include alkylamino, dialkylamino, or arylamino. If the term "amino" is not a terminal group (e.g., alkylcarbonylamino), it is -NR X It is represented by -. X This is synonymous with what is defined above.

[0134] As used herein, the “cycloalkyl” group refers to a saturated carbocyclic, monocyclic, or bicyclic (fused or crosslinked) ring of 3 to 10 (e.g., 5 to 10) carbon atoms. Examples of cycloalkyl groups include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, adamantyl, norbornyl, Cuville, octahydroindenyl, decahydronaphthyl, bicyclo[3.2.1]octyl, bicyclo[2.2.2]octyl, bicyclo[3.3.1]nonyl, bicyclo[3.3.2.]decyl, bicyclo[2.2.2]octyl, adamantyl, or ((aminocarbonyl)cycloalkyl)cycloalkyl.

[0135] As used herein, the "heterocycloalkyl" group refers to a 3- to 10-membered monocyclic or bicyclic (fused or bridged) saturated ring structure (e.g., a 5- to 10-membered monocyclic or bicyclic), where one or more ring atoms are heteroatoms (e.g., N, O, S, or a combination thereof). Examples of heterocycloalkyl groups include piperidyl, piperadyl, tetrahydropyranyl, tetrahydrofuryl, 1,4-dioxolanyl, 1,4-dithianyl, 1,3-dioxolanyl, oxazolidyl, isoxazolidyl, morpholinyl, thiomorpholyl, octahydrobenzofuryl, octahydroclomenyl, octahydrothioclomenyl, octahydroindolyl, octahydropyrindinyl, decahydroquinolinyl, octahydrobenzo[b]thiophenyl, 2-oxa-bicyclo[2.2.2]octyl, 1-aza-bicyclo[2.2.2]octyl, 3-aza-bicyclo[3.2.1]octyl, and 2,6-dioxa-tricyclo[3.3.1.0]nonyl. Monocyclic heterocycloalkyl groups can be fused with a phenyl moiety to form structures such as tetrahydroisoquinoline, which would be classified as heteroaryls.

[0136] As used herein, the “heteroaryl” group refers to a monocyclic, bicyclic, or tricyclic ring system having 4 to 15 ring atoms, where one or more ring atoms are heteroatoms (e.g., N, O, S, or a combination thereof), and the monocyclic ring system is aromatic, or at least one of the rings in the bicyclic or tricyclic ring system is aromatic. Heteroaryl groups include benzo-fusion ring systems having 2 to 3 rings. For example, benzo-fusion groups include benzos fused with one or two 4 to 8-membered heterocyclic aliphatic moieties (e.g., indolidyl, indolyl, isoindolyl, 3H-indolyl, indolinyl, benzo[b]furyl, benzo[b]thiophenyl, quinolinyl, or isoquinolinyl). Some examples of heteroaryls are pyridyl, 1H-indazolyl, furyl, pyrrolyl, thienyl, thiazolyl, oxazolyl, imidazolyl, tetrazolyl, benzofuryl, isoquinolinyl, benzthiazolyl, xanthene, thioxanthene, phenothiazine, dihydroindole, benzo[1,3]dioxole, benzo[b]furyl, benzo[b]thiophenyl, indazolyl, benzimidazolyl, benzthiazolyl, prill, cinnolyl, quinolyl, quinazolyl, cinnolyl, phthalazyl, quinazolyl, quinoxalil, isoquinolyl, 4H-quinolidyl, benzo-1,2,5-thiadiazole, or 1,8-naphthilidyl.

[0137] Examples of monocyclic heteroaryls, though not limited to them, include furyl, thiophenyl, 2H-pyrrolyl, pyrrolyl, oxazolyl, tazolyl, imidazolyl, pyrazolyl, isoxazolyl, isothiazolyl, 1,3,4-thiadiazolyl, 2H-pyranyl, 4H-planyl, pyridyl, pyridazyl, pyrimidyl, pyrazolyl, pyrazyl, or 1,3,5-triazyl. Monocyclic heteroaryls are numbered according to standard chemical nomenclature.

[0138] Examples of bicyclic heteroaryls include indolidyl, indolyl, isoindolyl, 3H-indolyl, indolinyl, benzo[b]furyl, benzo[b]thiophenyl, quinolinyl, isoquinolinyl, indolidinyl, isoindolyl, indolyl, benzo[b]furyl, bexo[b]thiophenyl, indazolyl, benzimimidazyl, benzthiazolyl, prinyl, 4H-quinolidyl, quinolyl, isoquinolyl, cinnolyl, phthalazyl, quinazolyl, quinoxalyl, 1,8-naphthilidyl, or pteridyl. Bicyclic heteroaryls are numbered according to standard chemical nomenclature.

[0139] As used herein, the term “processing rate” refers to the weight percentage of a component in a lubricating composition.

[0140] The weight-average molecular weight (Mw) and number-average molecular weight (Mn) can be determined using a gel permeation chromatography (GPC) instrument or similar instrument from Waters, and data processed with Waters Empower Software or similar software using commercially available polystyrene standards (with Mn values ​​ranging from 180 to approximately 18,000 as calibration standards). See, for example, WWYau, JJKirkland and DDBly, "Modern Size Exclusion Liquid Chromatography," John Wiley and Sons, New York, 1979, which is also incorporated herein by reference. [Examples]

[0141] A better understanding of this disclosure and its many advantages can be made apparent by the following examples. The following examples are illustrative and not limiting in any way to their scope or intent. Those skilled in the art will readily understand that variations of the components, methods, steps, and devices described in these examples can be used. Unless otherwise specified or made apparent in the context of the discussion throughout the following examples, all percentages, ratios, and parts described in this disclosure are by weight.

[0142] The heavy-duty crankcase lubricant compositions of the Comparative Example and the present invention were evaluated for piston cleanliness on a steel piston according to the OM471 piston cleanliness test of CEC L-118-21. The lubricant compositions evaluated in this example contained sulfonate and / or phenate detergents and provided the fluid relationships shown in Table 3 below. Except for changes in the detergent system, Invention 1 and Comparative Example 1 contained the same additive package (having the same treatment rate) in all other respects, and therefore had the same dispersant system, anti-wear system, antioxidant system, defoamer, pour point depressant, viscosity modifier, the remainder of API Group III base oil, and achieved a target KV100 of 11.4 to about 11.7 cSt as measured according to ASTM D445. The antioxidant systems of Invention 1 and Comparative Example 1 contained at least 1.0 weight percent diphenylamine, at least 1.0 weight percent hindered phenol, and less than 0.2 weight percent molybdenum-containing compound. In addition to the changes in the detergent system, Comparative Example 2 also included a reduction in the dispersant treatment rate in its dispersant system, a reduction in the antioxidant treatment rate in its antioxidant system, and an increase in the zinc dithiophosphate treatment rate in its anti-wear system. It should also be noted that each fluid contained slight changes in the process oil due to the differences in the amounts of additives provided. The soap content was calculated as described under subheading 7.2.5. Detergent Classification on pages 219-220 of the textbook entitled "Chemistry and Technology of Lubricants," 3rd edition, edited by RMMortier and STOrszulik, copyright 2010.

[0143] [Table 3] * The TBN of each sulfonate and phenate detergent was measured according to ASTM D2896, and the TBN contribution from the sulfonates was calculated based on their treatment rate in the lubricating oil composition.

[0144] The cleaning agent and dispersing agent systems of the heavy-duty crankcase lubricant shown in Table 3 above contained the following components. • Cleaning agent A was a hyperbasic calcium phenate containing approximately 250 TBN and approximately 9.3 weight percent calcium. • Cleaning agent B was calcium overbasic sulfonate containing approximately 307 TBN and approximately 11.9 weight percent calcium. • Cleaning agent C was low-basic calcium sulfonate containing approximately 28 TBN and approximately 2.6 weight percent calcium. The dispersant system contained a combination of polyisobutylene succinimide dispersants derived from highly reactive polyisobutylene, each having a number-average molecular weight of 1000 to 2500. Each dispersant contained 1.0 to 1.7 weight percent nitrogen. The antioxidant system contained a mixture of alkylated diphenylamine, a hindered phenol antioxidant, and a molybdenum-containing compound. The wear-resistant system contains one or more zinc dithiophosphates that provide phosphorus to the fluid.

[0145] The heavy-duty lubricants listed in Table 3 were evaluated for piston cleanliness using steel pistons according to the OM471 piston cleanliness test (CEC L-118-21). The results are provided in Table 4 below. Comparative Example 1, which was previously acceptable in the earlier OM501LA (CEC L-101-08) piston cleanliness test when using aluminum pistons, did not achieve high piston cleanliness when tested using the newer OM471 test for steel pistons. It was unexpected that Invention 1, which contains only sulfonate soap, achieved high piston cleanliness on steel pistons under the newer, more stringent OM471 test. Invention 1 is further expected to achieve high piston cleanliness in a modified version of the OM471 test using a shorter test period.

[0146] [Table 4] * The fluids in Comparative Examples 1 and 2 were unable to complete the full test and recorded results only after 400 hours.

[0147] As used herein and in the appended claims, the singular forms “a,” “an,” and “the” include multiple references unless explicitly and clearly limited to one. For example, a reference to “antioxidants” includes two or more different antioxidants. Where used herein, the term “includes” and its grammatical variations are intended to be non-limiting so as not to exclude other similar items that may be substituted for or added to the items in the list.

[0148] For the purposes of this specification and the appended claims, unless otherwise indicated, all numbers representing quantities, percentages, or proportions, and other numerical values ​​used herein and in the claims should be understood in all cases as being modified by the term “approximately.” Therefore, unless otherwise indicated, the numerical parameters described herein and in the appended claims are approximations that may vary depending on the desired characteristics sought by this disclosure. At a minimum, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should be interpreted at least in terms of the number of significant figures reported and by applying ordinary rounding techniques.

[0149] It should be understood that each component, compound, substituent, or parameter disclosed herein is disclosed for use alone or in combination with any one or more other components, compounds, substituents, or parameters disclosed herein.

[0150] It should be further understood that each range disclosed herein should be interpreted as a disclosure of each specific value within the disclosure range having the same number of significant figures. Therefore, for example, the range 1–4 should be interpreted as a clear disclosure of any range of such values, not just the values ​​1, 2, 3, and 4.

[0151] It should be further understood that each lower limit of each range disclosed herein should be interpreted as being disclosed in combination with each upper limit of each range and each specific value within each range disclosed herein for the same component, compound, substituent, or parameter. Therefore, this disclosure should be interpreted as a disclosure of all ranges derived by combining each lower limit of each range with each upper limit of each range, or with each specific value within each range, or by combining each upper limit of each range with each specific value within each range. That is, it should also be further understood that any range between endpoint values ​​within a broad range is also considered herein. Therefore, the range 1-4 also means ranges such as 1-3, 1-2, 2-4, 2-3, etc.

[0152] Furthermore, any specific amounts / values ​​of components, compounds, substituents, or parameters disclosed in the description or examples should be interpreted as disclosures of either a lower or upper limit of a range, and can therefore be combined with any other lower or upper limit or specific amounts / values ​​in the range for the same component, compound, substituent, or parameter disclosed elsewhere in this application to form a range for that component, compound, substituent, or parameter.

[0153] While specific embodiments have been described, alternatives, modifications, variations, improvements, and substantial equivalents may emerge that are not currently anticipated or can not be anticipated by the applicants or others skilled in the art. Accordingly, the attached claims filed and any modified attached claims are intended to encompass all such alternatives, modifications, variations, improvements, and substantial equivalents.

[0154] This disclosure also relates to the following numbered embodiments. 1. A method for lubricating a heavy-duty diesel engine having a steel piston, This includes lubricating the steel pistons of a heavy-duty diesel engine with a lubricating oil composition. The lubricating oil composition comprises (i) a detergent system consisting of one or more alkaline earth metal sulfonate detergents that provide the lubricating oil composition with 0.3 to about 1 weight percent of sulfonate soap, and (ii) a dispersant system consisting of one or more polyisobutylene succinimide dispersants that provide the lubricating oil composition with at least about 5 weight percent of one or more dispersants. A method comprising using one or more polyisobutylene succinimide dispersants derived from highly reactive polyisobutylene having a number-average molecular weight of approximately 1,200 to approximately 2,500 and contributing more than 650 ppm of nitrogen to a lubricating oil composition. 2. A method for lubricating a heavy-duty diesel engine having a steel piston as described in Embodiment 1, wherein the heavy-duty diesel engine is operated under the conditions shown in the OM471 piston cleanliness test of CEC L-118-21. 3. A method for lubricating a heavy-duty diesel engine having a steel piston as described in Embodiment 1, wherein the heavy-duty diesel engine is configured to power a vehicle having a gross vehicle weight rating of approximately 6,000 pounds or more. 4. A method for lubricating a heavy-duty diesel engine having a steel piston as described in Embodiment 1, wherein the cleaning agent system comprises one or more overbasic calcium sulfonate cleaning agents and one or more low-basic calcium sulfonate cleaning agents, the overbasic cleaning agent having a total base number (TBN) of at least about 300 mg KOH / g, and the low-basic cleaning agent having a total base number (TBN) of about 175 mg KOH / g or less, and the total base number (TBN) is determined by ASTM D2896. 5. A method for lubricating a heavy-duty diesel engine having a steel piston as described in Embodiment 4, wherein the lubricating composition comprises about 0.3 to about 0.7 weight percent of sulfonate soap. 6. A method for lubricating a heavy-duty diesel engine having a steel piston according to Embodiment 4, wherein the cleaning agent system comprises one or more overbasic sulfonate cleaning agents in an effective amount to provide the cleaning agent system with at least about 5 mg KOH / g, and one or more low-basic sulfonate cleaning agents in an effective amount to provide about 25 to about 40 weight percent of cleaning agent soap. 7. A method for lubricating a heavy-duty diesel engine having a steel piston according to Embodiment 1, wherein the cleaning agent system essentially consists of a calcium sulfonate cleaning agent. 8. A method for lubricating a heavy-duty diesel engine having a steel piston according to Embodiment 1, wherein the cleaning agent system substantially does not contain a magnesium sulfonate cleaning agent, substantially does not contain a phenate cleaning agent, or is a combination thereof. 9. A method for lubricating a heavy-duty diesel engine having a steel piston as described in Embodiment 1, wherein the lubricating oil composition contains about 50 ppm to about 200 ppm of molybdenum provided by an oil-soluble molybdenum compound selected from the group consisting of molybdenum dithiocarbamate, molybdenum dialkyldithiophosphate, sulfur-free organic amide molybdenum complex, or mixtures thereof. 10. A method for lubricating a heavy-duty diesel engine having a steel piston according to claim 1, wherein the lubricating oil composition further comprises about 0.5 to about 5 weight percent of one or more ashless antioxidants selected from hindered phenols, aromatic amines, alkylated diphenylamines, phenyl-α-naphthylamines, alkylated phenyl-α-naphthylamines, hindered non-aromatic amines, sulfurized olefins, or mixtures thereof. 11. A method for lubricating a heavy-duty diesel engine having a steel piston as described in Embodiment 1, wherein the lubricating oil composition contains up to about 1200 ppm of phosphorus from one or more metal dihydrocarbyl dithiophosphate compounds having hydrocarbyl groups derived from a mixture of linear or branched primary alcohols and linear or branched secondary alcohols. 12. A heavy-duty crankcase lubricant composition suitable for diesel engines with a gross vehicle weight of approximately 6,000 pounds or more, One or more base oils with lubricating viscosity, A cleaning agent system comprising one or more alkaline earth metal sulfonate cleaning agents that provide up to approximately 1 weight percent of sulfonate soap to the lubricating oil composition, A dispersant system comprising one or more polyisobutylene succinimide dispersants that provide at least about 5 weight percent of one or more dispersants to the lubricating composition, A heavy-duty crankcase lubricant composition comprising one or more polyisobutylene succinimide dispersants, each having a number-average molecular weight of approximately 1,200 to 2,500 and derived from highly reactive polyisobutylene that contributes more than 650 ppm of nitrogen to the lubricant composition. 13. The heavy-duty crankcase lubricant composition according to Embodiment 12, wherein the lubricant composition achieves at least about 90% steel piston cleanliness when measured by the OM471 piston cleanliness test (CEC L-118-21). 14. The heavy-duty crankcase lubricating oil composition according to Embodiment 12, wherein the detergent system comprises one or more overbasic calcium sulfonate detergents and one or more low-basic calcium sulfonate detergents, the overbasic detergent having a total base number (TBN) of at least about 200 mg KOH / g, and the low-basic detergent having a total base number (TBN) of about 175 mg KOH / g or less, and the total base number (TBN) is determined by ASTM D2896. 15. The heavy-duty crankcase lubricant composition according to Embodiment 13, wherein the cleaning agent system comprises one or more overbasic sulfonate cleaning agents in an effective amount to provide the cleaning agent system with at least about 5 mg KOH / g, and one or more low-basic sulfonate cleaning agents in an effective amount to provide about 25 to about 40 weight percent of cleaning agent soap. 16. The heavy-duty crankcase lubricant composition according to Embodiment 12, wherein the cleaning agent system essentially consists of a calcium sulfonate cleaning agent. 17. The heavy-duty crankcase lubricant composition according to Embodiment 12, wherein the cleaning agent system substantially does not contain a magnesium sulfonate cleaning agent, substantially does not contain a phenate cleaning agent, or is a combination thereof. 18. The heavy-duty crankcase lubricant composition according to Embodiment 12, wherein the lubricant composition contains about 50 ppm to about 200 ppm of molybdenum provided by an oil-soluble molybdenum compound selected from the group consisting of molybdenum dithiocarbamate, molybdenum dialkyldithiophosphate, sulfur-free organic amide molybdenum complex, or mixtures thereof. 19. The heavy-duty crankcase lubricant composition according to Embodiment 12, further comprising about 0.5 to about 5 weight percent of one or more ashless antioxidants selected from hindered phenols, aromatic amines, alkylated diphenylamines, phenyl-α-naphthylamines, alkylated phenyl-α-naphthylamines, hindered non-aromatic amines, sulfurized olefins, or mixtures thereof. 20. The heavy-duty crankcase lubricant composition according to Embodiment 1, wherein the lubricant composition contains up to about 1200 ppm of phosphorus from one or more metal dihydrocarbyl dithiophosphate compounds having hydrocarbyl groups derived from a mixture of linear or branched primary alcohols and linear or branched secondary alcohols.

Claims

1. A method for lubricating a heavy-duty diesel engine having a steel piston, This includes lubricating the steel piston of the heavy-duty diesel engine with a lubricating oil composition. The lubricating oil composition comprises (i) a detergent system comprising one or more alkaline earth metal sulfonate detergents that provide the lubricating oil composition with 0.3 to about 1 weight percent of sulfonate soap, and (ii) a dispersant system comprising one or more polyisobutylene succinimide dispersants that provide the lubricating oil composition with at least about 5 weight percent of one or more dispersants. A method wherein the one or more polyisobutylene succinimide dispersants are derived from highly reactive polyisobutylene having a number average molecular weight of about 1,200 to about 2,500 and providing more than 650 ppm of nitrogen to the lubricating oil composition.

2. A method for lubricating a heavy-duty diesel engine having a steel piston according to claim 1, wherein the heavy-duty diesel engine is operated under the conditions specified in the OM471 piston cleanliness test of CEC L-118-21, and / or the heavy-duty diesel engine is configured to power a vehicle having a gross vehicle weight rating of about 6,000 pounds or more.

3. A method for lubricating a heavy-duty diesel engine having a steel piston according to claim 1, wherein the cleaning agent system comprises one or more overbasic calcium sulfonate cleaning agents and one or more low-basic calcium sulfonate cleaning agents, the overbasic cleaning agent having a total base number (TBN) of at least about 300 mg KOH / g, and the low-basic cleaning agent having a total base number (TBN) of about 175 mg KOH / g or less, and the total base number (TBN) is determined by ASTM D2896.

4. A method for lubricating a heavy-duty diesel engine having a steel piston according to claim 3, wherein the lubricating composition comprises about 0.3 to about 0.7 weight percent of sulfonate soap.

5. A method for lubricating a heavy-duty diesel engine having a steel piston according to claim 3, wherein the cleaning agent system comprises an effective amount of one or more of the overbasic sulfonate cleaning agents to provide the cleaning agent system with at least about 5 mg KOH / g, and an effective amount of one or more of the lowbasic sulfonate cleaning agents to provide about 25 to about 40 weight percent of the cleaning agent soap.

6. A method for lubricating a heavy-duty diesel engine having a steel piston according to claim 1, wherein the cleaning agent system essentially consists of a calcium sulfonate cleaning agent and / or the cleaning agent system substantially does not contain a magnesium sulfonate cleaning agent, substantially does not contain a phenate cleaning agent, or is a combination thereof.

7. A method for lubricating a heavy-duty diesel engine having a steel piston according to claim 1, wherein the lubricating oil composition contains about 50 ppm to about 200 ppm of molybdenum provided by an oil-soluble molybdenum compound selected from the group consisting of molybdenum dithiocarbamate, molybdenum dialkyldithiophosphate, sulfur-free organic amide molybdenum complex, or mixtures thereof.

8. A method for lubricating a heavy-duty diesel engine having a steel piston according to claim 1, wherein the lubricating oil composition further comprises about 0.5 to about 5 weight percent of one or more ashless antioxidants selected from hindered phenols, aromatic amines, alkylated diphenylamines, phenyl-α-naphthylamines, alkylated phenyl-α-naphthylamines, hindered non-aromatic amines, sulfurized olefins, or mixtures thereof.

9. A method for lubricating a heavy-duty diesel engine having a steel piston according to claim 1, wherein the lubricating oil composition contains up to about 1200 ppm of phosphorus from one or more metal dihydrocarbyl dithiophosphate compounds having hydrocarbyl groups derived from a mixture of linear or branched primary alcohols and linear or branched secondary alcohols.

10. A heavy-duty crankcase lubricant composition suitable for diesel engines with a total vehicle weight of approximately 6,000 pounds or more, One or more base oils with lubricating viscosity, A cleaning agent system comprising one or more alkaline earth metal sulfonate cleaning agents that provide up to approximately 1 weight percent of sulfonate soap to the lubricating oil composition, The lubricating composition comprises a dispersant system containing one or more polyisobutylene succinimide dispersants that provide at least about 5 weight percent of the one or more dispersants, A heavy-duty crankcase lubricant composition wherein the one or more polyisobutylene succinimide dispersants have a number average molecular weight of about 1,200 to about 2,500 and are derived from highly reactive polyisobutylene that contribute more than 650 ppm of nitrogen to the lubricant composition.

11. The heavy-duty crankcase lubricant composition according to claim 10, wherein the lubricant composition achieves at least about 90% steel piston cleanliness when measured by the OM471 piston cleanliness test (CEC L-118-21).

12. The heavy-duty crankcase lubricating oil composition according to claim 10, wherein the detergent system comprises one or more overbasic calcium sulfonate detergents and one or more low-basic calcium sulfonate detergents, the overbasic detergent having a total base number (TBN) of at least about 200 mg KOH / g, and the low-basic detergent having a total base number (TBN) of about 175 mg KOH / g or less, and the total base number (TBN) is determined by ASTM D2896.

13. The heavy-duty crankcase lubricating oil composition according to claim 10, wherein the cleaning agent system comprises an effective amount of one or more overbasic sulfonate cleaning agents to provide the cleaning agent system with at least about 5 mg KOH / g, and an effective amount of one or more lowbasic sulfonate cleaning agents to provide about 25 to about 40 weight percent cleaning agent soap, and / or the cleaning agent system essentially consists of a calcium sulfonate cleaning agent, and / or the cleaning agent system substantially does not contain a magnesium sulfonate cleaning agent, substantially does not contain a phenate cleaning agent, or is a combination thereof.

14. The heavy-duty crankcase lubricant composition according to claim 10, wherein the lubricant composition comprises about 50 ppm to about 200 ppm of molybdenum provided by an oil-soluble molybdenum compound selected from the group consisting of molybdenum dithiocarbamate, molybdenum dialkyldithiophosphate, sulfur-free organic amide molybdenum complex, or mixtures thereof.

15. The heavy-duty crankcase lubricant composition according to claim 10, wherein the lubricant composition further comprises about 0.5 to about 5 weight percent of one or more ashless antioxidants selected from hindered phenols, aromatic amines, alkylated diphenylamines, phenyl-α-naphthylamines, alkylated phenyl-α-naphthylamines, hindered non-aromatic amines, sulfurized olefins, or mixtures thereof, and / or the lubricant composition comprises up to about 1200 ppm of phosphorus from one or more metal dihydrocarbyl dithiophosphate compounds having hydrocarbyl groups derived from a mixture of linear or branched primary alcohols and linear or branched secondary alcohols.

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