BACKGROUND OF THE INVENTION

The field of this invention relates to the latest technology for substantially reducing steel-to-steel wear along with eliminating the need for Zinc Dialkyldithiophosphates (ZDDP) in motor oils as an anti-wear component. The composition of this invention has been shown to modify the plastic response of steel while having a positive influence on the chemical reactivity of the surfaces subjected to being worn down due to friction. Specifically, based on the tribological testing detailed in U.S. 62/109,172, spectroscopic analysis of the wear tracks of an engine disk revealed that chemical elements like P, S, Mn, Zn, which can be from the ZDDP in the oil, were not detected. This suggests that this composition inhibits the reaction of ZDDP and renders it unnecessary for reducing wear.

This is important, because today there is a movement within a number of states and countries to remove or substantially reduce the need for ZDDP in motor oils. Environmentalists in the US have lobbied both State and Federal departments to legislate such a ban. Unfortunately, governments have been reluctant to issue or enforce such a ban until a cost-effective alternative becomes available which can have the same or better anti-wear performance results as ZDDP, while eliminating the need for ZDDP itself.

There are in fact two types of zinc-thiophosphates universally added to motor oils used today: zinc di-alkyl-di-thiophosphates (which is ZDDP proper), and/or zinc di-thiophosphate (which is often abbreviated to ZDTP). Unless otherwise specified, when the acronym ZDDP is used in this disclosure, it is being used to refer to either of these, with or without the di-alkyl group. And specifically, the composition of this invention eliminates the need for either of ZDDP-proper, or ZDTP to be used in motor oils any longer.

The automotive industry was much simpler in the early days. Engines bearings were made from a soft tin/copper/antimony alloy, commonly referred to as babbitt. This alloy is relatively inert chemically and has the ability to absorb small amounts of foreign particulate material. But, as engine horsepower increased, babbitt alloy surfaces proved to be inadequate to bear the increased loading on these surfaces.

Thus, the need for harder bearings arose, and new types of bearings with cadmium/silver, cadmium/nickel, and copper/lead construction were developed. Such bearings were much stronger, but were not as chemically inert as babbitt and could be attacked by the acids generated from oil oxidation. These new bearings were unable to absorb foreign material such as carbon, grit and wear debris into the bearing material, and consequently, improvements in oil filtration were developed and used in vehicles to decrease premature wear.

Further, bearing corrosion inhibitors, anti-wear agents and acid inhibitor compounds were developed to protect these new bearings. There was a need to protect the bearings against both corrosive and mechanical wear, and many of these compounds served both functions. Compounds such as sulfurized sperm oil, organic phosphates, dithiocarbonates and dithiophosphates were experimented with to reduce premature wear. In 1941, Lubrizol developed Zinc Dialkyldithiophosphates, which remain the most commonly-used form of ZDDP, and introduced these to the market.

Initially, ZDDP was added to motor oils in low concentrations of less than 0.3% by volume as a bearing passivator, defined as treating or coating a metal in order to reduce the chemical reactivity of its surface. In addition, ZDDP was found to be a remarkably effective anti-wear agent; a true extreme-pressure (EP) additive for heavily loaded steel-on-steel sliding mechanisms such as camshafts and valve lifters or tappets. During these years, there was little if any concern about the impact of ZDDP upon the environment.

For years, these ZDDP additives have been providing sufficient anti-wear service, starting with the early days of gasoline and diesel non-detergent motor oils, through the present day. Diesel engines of more than half a century ago, which generally operated at lower speeds and were more massively built, did not exhibit the same wear problems. But in a gasoline engine, the valve train is more heavily stressed due to the higher engine speeds, and these additives have played and continue to play an important role in reducing wear.

Current and previous motor oils have depended upon the use of ZDDP as a means to protect against premature wear between bearing surfaces and from steel-to-steel contact. In view especially of the detrimental impact of ZDDP on the environment, it would be desirable to have available a replacement additive which can eliminate the need for ZDDP, which additive at the same time provides the same level of protection—and even better protection—for engine components.

In U.S. Pat. No. 7,745,382, which was the first of several US and foreign patents issued to Ronald J. Sloan and assigned to BestLine International Research Inc. (BestLine) who are the inventor and assignee for the present application as well, it was disclosed that a synthetic lubricant additive comprising polymerized alpha-olefins (PAOs), hydroisomerized hydro-treated severe hydrocracked base oil, and synthetic sulfonates could provide better engine lubrication and reduce engine wear, and that in fact the PAOs and the base oils could be the primary composition for a broad range of lubricants useful in many different circumstances including and beyond automotive applications, and as applied to many different materials including and beyond steel. This includes diesel fuel additives (U.S. Pat. No. 8,062,388 et. seq.), gasoline additives (U.S. Pat. No. 7,931,704 et. seq.), general purpose lubricants (U.S. Pat. No. 8,022,020 et. seq.), marine lubricants (U.S. Pat. No. 8,334,244 et. seq.) and even golf club cleaners (U.S. Pat. No. 8,071,522 et. seq.).

But until the tribological testing detailed in U.S. 62/109,172, the tribological mechanism underlying the effectiveness of BestLine's synthetic lubricant additive was not fully understood. This testing established that not only did this PAO, base oil and (optionally) synthetic sulfonate composition enhance lubrication, but this composition was also found to modify the plastic response of the investigated steel and to influence the chemical reactivity of the worn surfaces. Particularly, as noted above, because elements like P, S, Mn, Zn were not detected when this composition was added to engine oils with ZDDP, this means that this composition inhibits the reaction of ZDDP and renders ZDDP unnecessary for reducing wear if the PAO and base oil is employed as a substitute.

Thus, it was only with the new understandings first disclosed in U.S. 62/109,172, that consideration could be given to adding this PAO, base oil and optionally synthetic sulfonate composition to motor oils, while at the same time removing all of the ZDDP and/or ZDTP from these very same motor oils. Thus, the addition of this PAO, base oil, sulfonate composition to motor oils simultaneously with the removal of all forms of ZDDP not only reduces engine wear by superior lubrication, but also favorably modifies the plastic response of all steel elements which it lubricates, and at the same time solves an important environmental problem.

The use of this composition to improve motor oils while removing the environmental harm caused by ZDDP and ZDTP is applicable to all of the five groups of motor oil as defined by the American Petroleum Institute (API). This API categorization is hereby incorporated by reference into this disclosure and its associated claims. Specifically, the September 2011 standards of the API at http://www.api.org/˜/media/files/certification/engine-oil-diesel/publications/appendix-e-rev-09-01-11.pdf?la=en specify as follows:

“All base stocks are divided into five general categoriesa. Group I base stocks contain less than 90 percent saturates and/or greater than 0.03 percent sulfur and have a viscosity index greater than or equal to 80 and less than 120 using the test methods specified in Table E-1.b. Group II base stocks contain greater than or equal to 90 percent saturates and less than or equal to 0.03 percent sulfur and have a viscosity index greater than or equal to 80 and less than 120 using the test methods specified in Table E-1.c. Group III base stocks contain greater than or equal to 90 percent saturates and less than or equal to 0.03 percent sulfur and have a viscosity index greater than or equal to 120 using the test methods specified in Table E-1.d. Group IV base stocks are polyalphaolefins (PAO). PAOs can be interchanged without additional qualification testing as long as the interchange PAO meets the original PAO manufacturer's specifications in physical and chemical properties. The following key properties need to be met in the substituted stock:1) Kinematic viscosity at 100° C., 40° C., and −40° C.2) Viscosity index3) NOACK volatility4) Pour point5) Unsaturatese. Group V base stocks include all other base stocks not included in Group I, II, III, or IV.

TABLE E-1Analytical Methods for Base StockPropertyTest MethodSaturatesASTM D2007Viscosity indexASTM D2270SulfurASTM D1552(use one listed method)ASTM D2622ASTM D3120ASTM D4294ASTM D4927”

SUMMARY OF THE INVENTION

An additive and related method for modifying the plastic response of steel, the additive comprising: polymerized alpha olefins; hydroisomerized hydro-treated severe hydrocracked base oil; and optionally, synthetic sulfonates. A tribological study detailed in U.S. 62/109,172 and herein concludes that: (1) This additive significantly reduces wear of the carbon steel disk to 6% of the wear observed in pure oil without additive; (2) There is no obvious effect of the additive on friction except a slightly better stability with time of the coefficient of friction; (3) The additive appears to inhibit the reaction of ZDDP and renders ZDDP unnecessary for reducing wear. This suggests that the additive may be a replacement for ZDDP in motor oils; and (4) The additive was found to modify the plastic response of the investigated steel and to influence the chemical reactivity of the worn surfaces. Although testing was not conducted to establish the coefficient of friction, as this will be concluded at a later time, previous testing supports that the friction is reduced.

This invention is for a synthetic lubricant additive that can be added at various ratios to provide the need protect against steel-to-steel wear or between bearing and steel surfaces, as well as related method of manufacturing this additive and related methods of its use. Further, this additive can be added to synthetic, synthetic blends and non-synthetic motor oils (motor oils in all of Groups I through V) to provide them with the anti-wear protection necessary in today's high speed and low speed gasoline and diesel motor oils. Further the invention allows steel under extreme pressure to yield or to respond to plastic deformation without the fracturing of the metal surface.

The additive incorporates the use of polymerized alpha olefins (PAO); hydroisomerized hydro-treated severe hydrocracked base oil; and optionally, synthetic sulfonates. Further, one can optionally employ vacuum distilled non aromatic solvents and liquefied polytetrafluoroethylene (PTFE) and when combined into the additive a specific sequence, this forms a finished product that exceeds the metal-protecting capability and benefits of ZDDP while providing an environmentally-friendly replacement. Further this product provides protection against steel-to-steel contact while positively influencing the chemical reactivity of worn metal surfaces. Further this product in independent testing reported in provisional application U.S. 62/109,172 has demonstrated the ability to modify the plastic response of steel placed under extreme pressure.

As previous indicated the ingredients of this additive when blended in a very specific sequence under specific conditions will provide a lubricant that has shown its ability to replace the need for ZDDP as an anti-wear agent in motors oils. The blending is a combination of accurately-controlled sheering and homogenization of the compounds resulting in a long-term stable blend. Once blended in a specific sequence, simple purification or physical separation, such as distillation or freezing, does not constitute synthesis, in the manner, for example, of making synthetic Group III and Group IV from crude oil via a chemical reaction.

The finished product is a combination of:Polymerized Alpha-OlefinsHydroisomerized hydro-treated severe hydrocracked base oilOptionally, Synthetic sulfonatesOptionally, vacuum distilled non aromatic solvents (less than 0.5% aromatics)Optionally, liquefied polytetrafluoroethylene (PTFE) comprising a stable aqueous disbursement

Synthetic lubricants have been successfully used for some time. They have the ability to offer very-high-viscosity index, low volatility, superior oxidation resistance, high thermal stability, excellent temperature fluidity and low toxicity to the environment. These characteristics in a finished lubricant are very important in modern high-speed and high-horsepower engines. Further these characteristics benefit the long term goals of being less toxic to the environment while providing maximum protection for automotive components.

This synthetic lubricant when tested has demonstrated the ability to provide and exceed the anti-wear protection currently provided by the inclusion of ZDDP in motor oils. The synthetic lubricant can provide the necessary anti-wear in automotive, diesel and marine motor oil, but without the environmental impact of ZDDP. It has the ability to blend with, and be effective with, all of Group I, II, III, IV and Group base oils.

In its preferred embodiment, disclosed here is an environmentally-improved motor oil blend and related methods for properly lubricating components of an engine and favorably modifying a plastic response of components of the engine, the blend being free of zinc di-alkyl-di-thiophosphates (ZDDP) and free of zinc di-thiophosphate (ZDTP), comprising: a motor oil selected from the motor oil group consisting of Group I, Group II, Group III, Group IV, and Group V motor oils; a motor oil additive comprising alpha-olefins and hydroisomerized hydro-treated severe hydrocracked base oil; ZDDP omitted from the chemical constituents of the motor oil; and ZDTP omitted from the chemical constituents of the motor oil.

