U.S. patent application number 14/115365 was filed with the patent office on 2014-05-08 for lubricating oil compositions comprising fischer-tropsch derived base oils.
This patent application is currently assigned to Shell Internationale Research Maatschappij B.V.. The applicant listed for this patent is Peter Max Busse, Nigel Edmund Lunt, Stefan Bernhard Schleper, David John Wedlock. Invention is credited to Peter Max Busse, Nigel Edmund Lunt, Stefan Bernhard Schleper, David John Wedlock.
Application Number | 20140128303 14/115365 |
Document ID | / |
Family ID | 44170038 |
Filed Date | 2014-05-08 |
United States Patent
Application |
20140128303 |
Kind Code |
A1 |
Busse; Peter Max ; et
al. |
May 8, 2014 |
LUBRICATING OIL COMPOSITIONS COMPRISING FISCHER-TROPSCH DERIVED
BASE OILS
Abstract
Use of a lubricating oil composition comprising at least one
Fischer-Tropsch derived base oil for reducing exhaust port blocking
of a 2-stroke engine. The present invention also relates to a
2-stroke lubricating engine oil composition comprising (i) at least
one Fischer-Tropsch derived base oil having a kinematic viscosity
at 100.degree. C. in the range of from 2 to 30 mm.sup.2/s at
100.degree. C. and (ii) 5 wt % or greater of a hydrocarbon solvent;
wherein the lubricating engine oil composition has a Blocking Index
of greater than 130 as measured by the JASO M343-92 Exhaust System
Blocking Test Method.
Inventors: |
Busse; Peter Max; (Hamburg,
DE) ; Lunt; Nigel Edmund; (Chester Cheshire, GB)
; Schleper; Stefan Bernhard; (Hamburg, DE) ;
Wedlock; David John; (Cheshire Cheshire, GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Busse; Peter Max
Lunt; Nigel Edmund
Schleper; Stefan Bernhard
Wedlock; David John |
Hamburg
Chester Cheshire
Hamburg
Cheshire Cheshire |
|
DE
GB
DE
GB |
|
|
Assignee: |
Shell Internationale Research
Maatschappij B.V.
The Hague
NL
|
Family ID: |
44170038 |
Appl. No.: |
14/115365 |
Filed: |
May 3, 2012 |
PCT Filed: |
May 3, 2012 |
PCT NO: |
PCT/EP2012/058076 |
371 Date: |
January 16, 2014 |
Current U.S.
Class: |
508/518 ;
508/110 |
Current CPC
Class: |
C10N 2040/26 20130101;
C10M 143/00 20130101; C10M 2205/026 20130101; C10M 2205/17
20130101; C10M 169/04 20130101; C10N 2030/50 20200501; C10M 107/02
20130101; C10M 109/00 20130101; C10M 2203/104 20130101; C10N
2030/04 20130101; C10M 2205/173 20130101; C10N 2030/06 20130101;
C10M 2203/10 20130101; C10M 2207/026 20130101; C10N 2030/02
20130101 |
Class at
Publication: |
508/518 ;
508/110 |
International
Class: |
C10M 109/00 20060101
C10M109/00; C10M 169/04 20060101 C10M169/04 |
Foreign Application Data
Date |
Code |
Application Number |
May 5, 2011 |
EP |
11165010.7 |
Claims
1. A method comprising lubricating a 2-stroke engine with a
lubricating oil composition comprising at least one Fischer-Tropsch
derived base oil, wherein the lubricating oil composition provides
reduced exhaust port blocking in the 2-stroke engine.
2. The method of claim 1 wherein the Fischer-Tropsch derived base
oil has a kinematic viscosity at 100.degree. C. in the range of
from 2 mm.sup.2/s to 30 mm.sup.2/s.
3. The method of claim 1 wherein the Fischer-Tropsch derived base
oil has a kinematic viscosity at 100.degree. C. in the range of
from 2 mm.sup.2/s to 10 mm.sup.2/s.
4. The method of claim 3 wherein the Fischer-Tropsch derived base
oil has a kinematic viscosity at 100.degree. C. in the range of
from 2 mm.sup.2/s to 4 mm.sup.2/s.
5. The method of claim 1 wherein the Fischer-Tropsch derived base
oil has a kinematic viscosity at 100.degree. C. in the range of
from 12 mm.sup.2/s to 30 mm.sup.2/s.
6. The method of claim 5 wherein the Fischer-Tropsch derived base
oil has a kinematic viscosity at 100.degree. C. in the range of
from 18 mm.sup.2/s to 22 mm.sup.2/s.
7. The method of claim 5 wherein the lubricating oil composition
comprises less than 2 wt % of a Fischer-Tropsch derived base oil
having a kinematic viscosity at 100.degree. C. in the range of from
2 mm.sup.2/s to 10 mm.sup.2/s.
8. The method of claim 1 wherein the lubricating composition
comprises a first Fischer-Tropsch derived base oil having a
kinematic viscosity at 100.degree. C. in the range of from 2
mm.sup.2/s to 10 mm.sup.2/s and a second Fischer-Tropsch derived
base oil having a kinematic viscosity at 100.degree. C. in the
range of from 12 mm.sup.2/s to 30 mm.sup.2/s.
9. The method of claim 8 wherein the weight ratio of the first
Fischer-Tropsch derived base oil and the second Fischer-Tropsch
derived base oil is in the range of from 10:1 to 1:5.
10. The method of claim 1 wherein the lubricating oil composition
comprises 5 wt % or greater of a hydrocarbon solvent.
11. The method of claim 1 wherein the lubricating oil composition
additionally comprises a smoke suppression agent selected from the
group consisting of polybutene, polyisobutylene, and mixtures
thereof.
12. The method of claim 1 wherein the lubricating oil composition
additionally comprises a detergent/dispersant additive package.
13. The method of claim 1 wherein the lubricating composition
additionally comprises a lubricity additive.
14. A 2-stroke lubricating engine oil composition comprising (i) at
least one Fischer-Tropsch derived base oil having a kinematic
viscosity at 100.degree. C. in the range of from 2 to 30 mm.sup.2/s
and (ii) 5 wt % or greater of a hydrocarbon solvent; wherein the
lubricating engine oil composition has a Blocking Index of greater
than 130 as measured by the JASO M343-92 Exhaust System Blocking
Test Method.
15. A 2-stroke lubricating engine oil composition comprising (i) a
first Fischer-Tropsch derived base oil having a kinematic viscosity
at 100.degree. C. in the range of from 2 mm.sup.2/s to 10
mm.sup.2/s and (ii) a second Fischer-Tropsch derived base oil
having kinematic viscosity at 100.degree. C. in the range of from
18 mm.sup.2/s to 30 mm.sup.2/s; wherein the weight ratio of the
first Fischer-Tropsch derived base oil to the second
Fischer-Tropsch derived base oil is in the range of from 10:1 to
1:5, and wherein the lubricating engine oil composition has a
Blocking Index of greater than 130 as measured by the JASO M343-92
Exhaust System Blocking Test Method.
16. The method of claim 8 wherein the weight ratio of the first
Fischer-Tropsch derived base oil and the second Fischer-Tropsch
derived base oil is in the range of from 1.98:1 to 0.01:1.
17. The method of claim 1 wherein the lubricating engine oil
composition has a Blocking Index of greater than 130 as measured by
the JASO M343-92 Exhaust System Blocking Test Method.
18. The 2-stroke lubricating engine oil composition of claim 15
wherein the weight ratio of the first Fischer-Tropsch derived base
oil and the second Fischer-Tropsch derived base oil is in the range
of from 1.98:1 to 0.01:1.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to the use of a lubricating
oil composition comprising a Fischer-Tropsch derived base oil for
reducing exhaust port blocking of a two-stroke engine and to a
two-stroke lubricating engine oil composition having reduced
exhaust port blocking.
BACKGROUND OF THE INVENTION
[0002] Two-stroke gasoline engines are used in motorcycles as well
as in garden and recreational equipment such as lawn mowers, chain
saws, string trimmers, mopeds, snow-mobiles, outboard marine motors
and the like. Slow speed two-stroke diesel engines are used for
marine propulsion in very large ships.
[0003] To operate a two-stroke gasoline engine the crankcase holds
a mixture of two-stroke gasoline lubricant and fuel and the
crankcase serves as a pressurization chamber to force air/fuel into
the cylinder. This necessitates the use of a lubricating
composition which has been specially formulated for two-stroke
engines, instead of a high viscosity lubricating oil such as those
used in 4-stroke engines. The 2-stroke engine lubricant is mixed
with gasoline in prescribed proportions to lubricate the
crankshaft, connecting rod and cylinder walls.
[0004] Conventional two-stroke gasoline engine lubricants are
typically formulated with a mineral oil base oil or synthetic base
oil and a low-viscosity, low-boiling hydrocarbon solvent to enhance
the miscibility of the lubricant with the gasoline.
[0005] Some two-stroke engine oils have used ester base oils with
no low boiling solvent to reduce flammability and minimize smoky
emissions. However these lubricants often suffer from poor
oxidation stability. Other two-stroke engine oils have used
polyalphaolefin base oils having improved low temperature
properties. Both PAOs and ester base oils suffer from the
disadvantage of being limited in supply and very expensive.
[0006] A variety of performance additives can be added to improve
the overall performance of the lubricant. In particular, a
two-stroke engine oil should meet the requirements set by standards
setting organizations, including Japanese Automobile Standard JASO
M345 2003 and International Standard ISO 1373832000(E).
[0007] Since conventional two-stroke engines tend to be rather
smoky, smoke-reducing additives are often added to the lubricant.
Examples of smoke-reducing additives include those that contain
metals, but these tend to be undesirable from an environmental
viewpoint. Other examples include synthetic basestocks, but these
tend to be expensive. Polybutenes and polyisobutylenes are also
commonly added for reducing smoke and as anti-scuffing agents. It
is taught in WO2007/050352 that polyisobutylenes contribute to
exhaust port deposits and clogging.
[0008] It would be desirable to provide a lubricating oil
composition which is suitable for use in a two-stroke engine oil
and which, in particular, provides improvements in exhaust port
blocking behaviour.
[0009] At the same time, it would also be desirable to provide a
2-stroke lubricating oil composition which exhibits reduced engine
wear, reduced pollution, good low-temperature performance, good
gasoline miscibility, high oxidation stability, high flash points,
and which meets the requirements of standard setting organizations
such as Japanese Automobile Standard JASO M345 2003 and
International Standard ISO 1373832000(E).
[0010] It has now surprisingly been found that by using a
Fischer-Tropsch derived base oil, preferably a heavy
[0011] Fischer-Tropsch derived base oil, as a base oil in a
two-stroke engine lubricating oil composition, an improved
two-stroke engine lubricating oil composition is provided which
exhibits, in particular, a reduction in exhaust port blocking.
SUMMARY OF THE INVENTION
[0012] According to the present invention there is provided the use
of a lubricating oil composition comprising at least one
Fischer-Tropsch derived base oil for reducing exhaust port blocking
of a 2-stroke engine.
[0013] According to another aspect of the present invention there
is provided a 2-stroke lubricating engine oil composition
comprising (i) at least one Fischer-Tropsch derived base oil having
a kinematic viscosity at 100.degree. C. in the range of from 2 to
30 mm.sup.2/s and (ii) 5 wt % or greater of a hydrocarbon solvent;
wherein the lubricating engine oil composition has a Blocking Index
of greater than 130 as measured by the JASO M343-92 Exhaust System
Blocking Test Method.
[0014] According to yet a further aspect of the present invention
there is provided a 2-stroke lubricating engine oil composition
comprising (i) a first Fischer-Tropsch derived base oil having a
kinematic viscosity at 100.degree. C. in the range of from 2
mm.sup.2/s to 10 mm.sup.2/s and (ii) a second Fischer-Tropsch
derived base oil having kinematic viscosity at 100.degree. C. in
the range of from 18 mm.sup.2/s to 30 mm.sup.2/s; wherein the
weight ratio of the first Fischer-Tropsch base oil to the second
Fischer-Tropsch base oil is in the range of from 10:1 to 1:5, and
wherein the lubricating engine oil composition has a Blocking Index
of greater than 130 as measured by the JASO M343-92 Exhaust System
Blocking Test Method.
[0015] It has surprisingly been found that the use of
Fischer-Tropsch derived base oil, preferably heavy Fischer-Tropsch
derived base oil, in the 2-stroke lubricating oil compositions
herein provides reduced exhaust port blocking.
[0016] The use of a Fischer-Tropsch derived base oil allows
replacement of polyisobutylenes on a viscometric basis.
[0017] It is to be expected that the same benefit would be manifest
in a 2-stroke diesel engine, especially a 2-stroke slow speed
marine diesel engine.
[0018] The 2-stroke lubricating oil compositions according to the
present invention also provide reduced engine wear, increased
lubricity, reduced pollution, an improved smoke index, good
low-temperature performance, satisfactory gasoline miscibility,
high oxidation stability, high flash points and reduced
flammability.
[0019] The 2-stroke engine oil of the present invention also meets
the requirements of Japanese Automobile Standard JASO M345 2003 and
International Standard ISO 1373832000(E).
DETAILED DESCRIPTION OF THE INVENTION
[0020] The 2-stroke lubricating oil composition for use herein
comprises at least one Fischer-Tropsch derived base oil.
[0021] Fischer-Tropsch derived base oils are known in the art. By
the term "Fischer-Tropsch derived" is meant that a base oil is, or
is derived from, a synthesis product of a Fischer-Tropsch process.
A Fischer-Tropsch derived base oil may also be referred to as a GTL
(Gas-To-Liquids) base oil. Suitable Fischer-Tropsch derived base
oils that may be conveniently used as the base oil in the
lubricating composition are those as for example disclosed in EP 0
776 959, EP 0 668 342, WO 97/21788, WO 00/15736, WO 00/14188, WO
00/14187, WO 00/14183, WO 00/14179, WO 00/08115, WO 99/41332, EP 1
029 029, WO 01/18156 and WO 01/57166.
[0022] The Fischer-Tropsch derived base oil preferably has a
kinematic viscosity at 100.degree. C. in the range of from 2
mm.sup.2/s to 30 mm.sup.2/s. The total amount of Fischer-Tropsch
derived base oil in the lubricating oil composition is preferably
in the range of from 5 wt % to 99 wt %, more preferably from 10 wt
% to 99 wt %.
[0023] In one embodiment of the present invention the lubricating
oil composition comprises a light Fischer-Tropsch derived base oil
having a kinematic viscosity at 100.degree. C. in the range of from
2 mm.sup.2/s to 10 mm.sup.2/s, preferably in the range of from 2
mm.sup.2/s to 4 mm.sup.2/s. In one embodiment, the light
Fischer-Tropsch derived base oil is present at a level of from 5 wt
% to 60 wt %, preferably at a level of from 20 wt % to about 60 wt
%.
[0024] In another embodiment of the present invention the
lubricating oil composition comprises a heavy Fischer-Tropsch
derived base oil having a kinematic viscosity at 100.degree. C. in
the range of from 12 mm.sup.2/s to 30 mm.sup.2/s, preferably in the
range of from 18 mm.sup.2/s to 22 mm.sup.2/s. The heavy
Fischer-Tropsch derived base oil is preferably present at a level
of from 5 wt % to about 60 wt %, preferably from 10 wt % to 50 wt
%.
[0025] In a preferred embodiment of the present invention the
lubricating oil composition comprises a heavy Fischer-Tropsch
derived base oil having a kinematic viscosity at 100.degree. C. in
the range of from 12 mm.sup.2/s to 30 mm.sup.2/s, preferably in the
range of from 18 mm.sup.2/s to 22 mm.sup.2/s, and less than 2 wt %
of a light Fischer-Tropsch base oil having a kinematic viscosity at
100.degree. C. in the range of from 2 mm.sup.2/s to 10 mm.sup.2/s.
In the latter embodiment, the lubricating oil composition is
preferably free of light Fischer-Tropsch derived base oil having a
kinematic viscosity at 100.degree. C. in the range of 2 mm.sup.2/s
to 20 mm.sup.2/s.
[0026] In yet another embodiment of the present invention, the
lubricating oil composition comprises a mixture of a first
Fischer-Tropsch oil which is a light Fischer Tropsch base oil
having a kinematic viscosity at 100.degree. C. in the range of from
2 mm.sup.2/s to 10 mm.sup.2/s, preferably in the range of from 2
mm.sup.2/s to 4 mm.sup.2/s, and a second Fischer-Tropsch base oil
which is a heavy Fischer-Tropsch base oil having a kinematic
viscosity at 100.degree. C. in the range of from 12 mm.sup.2/s to
30 mm.sup.2/s, preferably in the range of from 18 mm.sup.2/s to 22
mm.sup.2/s. In the latter embodiment, it is preferred that the
weight ratio of the first Fischer-Tropsch derived base oil and the
second Fischer-Tropsch derived base oil is in the range of from
10:1 to 1:5, more preferably in the range of from 1.98:1 to
0.01:1.
[0027] In addition to the Fischer-Tropsch derived base oil, the
lubricating composition herein may comprise one or more additional
base oils. There are no particular limitations regarding the
additional base oil(s) which can be used in the lubricating
composition of the present invention, and various conventional
mineral oils, synthetic oils as well as naturally derived esters
such as vegetable oils may be conveniently used.
[0028] The additional base oil may conveniently comprise mixtures
of one or more mineral oils and/or one or more synthetic oils;
thus, the term "base oil" may refer to a mixture containing more
than one base oil or base stock. Mineral oils include liquid
petroleum oils and solvent-treated or acid-treated mineral
lubricating oil of the paraffinic, naphthenic, or mixed
paraffinic/naphthenic type which may be further refined by
hydrofinishing processes and/or dewaxing.
[0029] Suitable base oils for use in the lubricating oil
compositions herein are Group I-III mineral base oils, Group IV
poly-alpha olefins (PAOs), and Group V base oils.
[0030] By "Group I", "Group II", "Group III" "Group IV" and "Group
V" base oils are meant lubricating oil base oils according to the
definitions of American Petroleum Institute (API) for categories
I-V. These API categories are defined in API Publication 1509, 16th
Edition, Appendix E, April, 2007.
[0031] Synthetic oils include hydrocarbon oils such as olefin
oligomers (including polyalphaolefin base oils; PAOs), dibasic acid
esters, polyol esters, polyalkylene glycols (PAGs), alkyl
naphthalenes and dewaxed waxy isomerates. API Group III hydrocarbon
base oils sold by the Shell Group under the designation "Shell
XHVI" (trade mark) may be conveniently used.
[0032] Poly-alpha olefin base oils (PAOs) and their manufacture are
well known in the art. Preferred poly-alpha olefin base oils that
may be used in the lubricating compositions may be derived from
linear C.sub.2 to C.sub.32, preferably C.sub.6 to C.sub.16, alpha
olefins. Particularly preferred feedstocks for said poly-alpha
olefins are 1-octene, 1-decene, 1-dodecene and 1-tetradecene.
[0033] The total amount of base oil incorporated in the lubricating
composition is preferably present in an amount in the range of from
60 to 99 wt. %, more preferably in an amount in the range of from
65 to 98 wt. % and most preferably in an amount in the range of
from 70 to 95 wt. %, with respect to the total weight of the
lubricating composition.
[0034] Preferably, the finished lubricating composition has a
kinematic viscosity in the range of from 2 to 30 mm.sup.2/s at 100
.degree. C., more preferably in the range of from 3 to 20
mm.sup.2/s, most preferably in the range of from 4 to 15
mm.sup.2/s.
[0035] Preferably, the lubricating oil composition comprises 5 wt %
or greater of a volatile hydrocarbon solvent. The inclusion of such
a solvent is for the purpose of improving the miscibility and/or
solubility of base oil and additives with gasoline or other
fuel.
[0036] Preferably the volatile hydrocarbon solvent is present in
the composition at a level in the range of 5 to 40 wt %, preferably
in the range of 10 wt % to 30 wt %, more preferably in the range of
from 20 wt % to 30 wt %, by weight of the total composition.
[0037] Examples of suitable volatile hydrocarbon solvents include
kerosene, Exxsol D80 commercially from Exxon Mobil Chemical
Company, Shellsol D70 commercially available from Shell
International Chemical Company and Fischer-Tropsch kerosene
commercially available from Shell International Petroleum
Company.
[0038] Another preferred component for use in the lubricating
compositions herein is a smoke-suppression agent. In a preferred
embodiment, the smoke-suppression agent is an olefinically
unsaturated polymer selected from the group consisting of
polybutene, polyisobutylene or a mixture of polybutene and
polyisobutylene, which has a number average molecular weight of 400
to 2200 and a terminal olefin content of at least 60 mol %, based
on the total number of double bonds in the polymer. These types of
smoke-suppression agents are taught in EP-A-1743932.
[0039] An example of a smoke-suppression agent is that commercially
available from BASF Corporation under the tradename Glissopal (RTM)
1000, an approximately 1000 Dalton poly-isobutylene. Other examples
would be poly-butylenes of similar molecular weight supplied by
Ineos Oligomers under the trade name Indopol.
[0040] The smoke-suppression agent is preferably present in the
composition at a level in the range of from 5% to 70%, preferably
in the range of from 10% to 55%, by weight of the total
composition.
[0041] One or more detergent/dispersant additive packages may be
included in the lubricating oil composition of the present
invention, preferably in an amount of from 1 to 25 wt %, more
preferably from 3 to 20 wt %, based on the total weight of
composition. Ashless, low-ash or ash-containing additives may be
used for this purpose.
[0042] Suitable ashless additives include polyamide,
alkenylsuccinimides, boric acid-modified alkenylsuccinimies,
phenolic amines and succinate derivatives or combinations of any
two or more such additives.
[0043] Suitable ash-containing detergent/dispersant additives
include alkaline earth metal (e.g. magnesium, calcium, barium),
salicylate, sulfonate, phosphonates or phenates or combinations of
any two or more such additives.
[0044] Commercially available two-stroke lubricant
detergent/dispersant additive packages include, for example,
Lubrizol 400, Lubrizol 6827, Lubrizol 6830, Lubrizol 600, Lubrizol
606, Oronite OLOA 9333, Oronite OLOA 340A, Oronite OLOA 6721 and
Oronite OLOA 9357.
[0045] The lubricating composition may further comprise additional
additives such as anti-wear additives, lubricity additives, extreme
pressure agents, anti-oxidants, friction modifiers, viscosity index
improvers, pour point depressants, rust or corrosion inhibitors,
defoaming agents and seal fix or seal compatibility agents.
[0046] The above-described additives may be present at a level in
the range of from 0.005% to 15%, preferably from 0.005% to 6%, by
weight of the lubricating oil composition.
[0047] As the person skilled in the art is familiar with the above
and other additives, these are not further discussed here in
detail. Specific examples of such additives are described in for
example Kirk-Othmer Encyclopedia of Chemical Technology, third
edition, volume 14, pages 477-526.
[0048] To operate a two-stroke gasoline engine the crankcase holds
a mixture of two-stroke gasoline lubricant and fuel. The
recommended mix ratio of two-stroke gasoline engine lubricant and
fuel are specified by the engine manufacturer. The fuels useful in
two-stroke gasoline engines are well known to those skilled in the
art and usually contain a major portion of a normally liquid fuel
such as a hydrocarbonaceous petroleum distillate fuel, e.g. spark
ignition engine fuel as defined by ASTM D4814-07, or motor gasoline
as defined by ASTM D439-89. Such fuels can also contain
non-hydrocarbonaceous materials such as alcohols, ethers, organo
nitro compounds and the like. Examples of suitable fuels include,
but are not necessarily limited to methanol, ethanol, diethyl
ether, methylethyl ether, nitro methane and liquid fuels derived
from vegetable and mineral sources such as corn, switch grass,
alpha shale and coal. Examples of such fuel mixtures are
combinations of gasoline and ethanol, diesel fuel and ether,
gasoline and nitro methane, etc. The fuel is preferably lead-free
gasoline.
[0049] Two-stroke gasoline engine lubricants are typically used in
admixture with fuels in amounts of about 20 to 250 parts by weight
of fuel per 1 part by weight of lubricating oil, preferably in the
range from 30 to 100 parts by weight of fuel per 1 part by weight
of lubricant.
[0050] It is important that the two-stroke lubricating oil
composition of the present invention meets the requirements set by
standards setting organizations, including Japanese Automobile
Standard JASO M345:2003 and International Standard ISO 1373832000
(E).
[0051] In particular, it has been found that the lubricating oil
compositions of the present invention provide an improved benefit
in terms of reduced exhaust port blocking. Such a benefit can be
measured by the standard test method JASO 343-92.
[0052] In particular, in preferred embodiments, the lubricating oil
compositions of the present invention have a Blocking Index of
greater than 130, preferably greater than 140, as measured by JASO
343-92.
[0053] The lubricating compositions may be conveniently prepared by
admixing the additives that are usually present in lubricating
compositions, for example as herein before described, with mineral
and/or synthetic base oil.
[0054] The present invention will now be described by reference to
the following Examples which are not intended to limit the scope of
the invention in any way.
EXAMPLES
Example 1 and Comparative Example A
[0055] To determine the effect of GTL base oil on exhaust port
blocking behaviour in a two-stroke motorcycle engine, two-stroke
motorcycle oils were prepared having the formulations set out in
Table 1 below. The formulations were prepared by mixing the
additives with the base oils according to conventional preparation
methods. To determine the effect of each composition on exhaust
system port blocking the Blocking Index for each example was
measured using the Exhaust System Blocking test method JASO
M343-92.
[0056] The results of these tests are shown in Table 1.
TABLE-US-00001 TABLE 1 Comparative Example A Example 1 HVI
160B.sup.1 37.4 0 HVI 65.sup.2 0 33.88 GTL 19.sup.3 0 13.52
polybutylene 950.sup.4 35 25 Shellsol D70B.sup.5 25 25 Additive
package.sup.6 2.5 2.5 Irganox L135.sup.7 0.1 0.1 Total (weight %)
100 100 Results: JASO Exhaust Port 98 176 Blocking Index
(M343-92)
[0057] 1. Mineral API Group I base oil commercially available from
Shell Pernis Refinery, Rotterdam [0058] 2. Mineral API Group I base
oil commercially available from Shell Pernis Refinery, Rotterdam
[0059] 3. Heavy Fischer-Tropsch base stock having a kinematic
viscosity at 100.degree. C. of 19 cSt as prepared according to U.S.
Pat. No. 7,354,508. [0060] 4. Polybutylene having a molecular
weight of 950 [0061] 5. ShellSol D70B solvent commercially
available from Shell International Chemical Company, Rotterdam, The
Netherlands [0062] 6. 2-stroke performance additive package
commercially available from Infineum, Milton Hill, Oxfordshire, UK
containing aminic dispersant, antioxidants (mixed hindered phenols
and aminic antioxidants), and over-based detergents from the range
calcium phenate and calcium salicylates. [0063] 7. Antioxidant
commercially available from CIBA Speciality Chemicals,Berne,
Switzerland
Examples 2-4 and Comparative Example B
[0064] To determine the effect of GTL base oil on exhaust port
blocking behaviour in two-stroke engines, two-stroke motorcycle
oils were prepared having the formulations set out in Table 2
below. The formulations were prepared by mixing the additives with
the base oils according to conventional preparation methods.
Various measurements were made on each of the engine lubricants
using the test methods detailed in Table 2. The results of these
tests are set out in Table 2.
TABLE-US-00002 TABLE 2 Comparative Example B Example 2 Example 3
Example 4 Performance 1.3 1.3 1.3 1.3 additive package .sup.8
Irganox L 0.1 0.1 0.1 0.1 135.sup.9 Infineum 0 0 0.25 0.25
P655.sup.10 HVI 160B.sup.11 44 44 44 0 HVI 60.sup.12 54.6 0 0 0 GTL
19.sup.13 0 0 0 44 GTL 3.sup.14 0 54.6 54.35 54.35 Total 100 100
100 100 (weight %): JASO 81 82 86 98 Lubricity (M340-92) JASO Smoke
47 49 50 51 Index (M342- 92) JASO Exhaust 52 71 81 203 Port
Blocking Index (M343- 92) Laboratory Tests: Vk 100.degree. C. 6.98
5.05 5.05 6.98 (ASTM D-445 (mm.sup.2/s) Vk 40.degree. C. 46.07
25.57 25.44 35.34 (ASTM D-445) (mm.sup.2/s) VI (ASTM D- 108 127 128
163 2270)
[0065] 8. 2-stroke performance additive package containing aminic
dispersant, antioxidants (mixed hindered phenols and aminic
antioxidants), over-based detergents from the range calcium
phenates and calcium salicylates [0066] 9. antioxidant commercially
available from CIBA Speciality Chemicals, Berne, Switzerland [0067]
10. Lubricity additive commercially available from Infinenum,
Milton Hill, Oxfordshire, UK [0068] 11. Mineral Group I base oil
commercially available from Shell Pernis Refinery, Rotterdam [0069]
12. Mineral Group I base oil commercially available from Shell
Pernis Refinery, Rotterdam [0070] 13. Fischer-Tropsch base stock
having a kinematic viscosity at 100.degree. C. of 19 cSt prepared
according to the method of U.S. Pat. No. 7,354,508. [0071] 14.
Fischer-Tropsch base stock having a kinematic viscosity at
100.degree. C. of 3 cSt prepared according to the method of U.S.
Pat. No. 7,354,508.
Example 5 and Comparative Examples C and D
[0072] 2-stroke engine oil compositions were prepared having the
formulations set out in Table 3. The formulations were prepared by
mixing the additives with the base oils according to conventional
preparation methods. In order to determine the exhaust port
blocking behaviour the 2 stroke engine oil compositions were
subject to the Exhaust Port Blocking Test Method JASO 343-92. The
results are shown in Table 3 below.
TABLE-US-00003 TABLE 3 Comparative Comparative Example C Example 5
Example D 2 stroke 25 25 25 solvent.sup.15 Polybutylene.sup.16 25
25 25 HVI 65.sup.17 27.96 33.88 32.40 HVI 650.sup.18 19.44 0 0 GTL
19.sup.19 0 13.52 0 Flavex 595.sup.20 0 0 15 Additive 2.5 2.5 2.5
Package.sup.21 Irganox L 135.sup.22 0.1 0.1 0.1 Total (weight %)
100 100 100 Physical Data: kV 40.degree. C. 40 33.05 38.03 kV
100.degree. C. 7.256 6.558 6.815 Density at 15.degree. C. 860 849.3
869 (Kg/m.sub.3) Pour Point/.degree. C. -39 -33 -33
Flashpoint/.degree. C. 83 84 83 Results (JASO- 343-92): JASO M
343-92 100 243 69 Port Blocking Index
[0073] 15. 2 stroke solvent ShellSol D70B solvent, commercially
available from Shell Chemicals, The Netherlands [0074] 16.
Polybutylene having a molecular weight of 950 [0075] 17. Mineral
API Group I base oil commercially available from Shell Pernis
Refinery, Rotterdam [0076] 18. brightstock commercially available
from Shell Pernis Refinery, Rotterdam [0077] 19. Heavy
Fischer-Tropsch base stock having a kinematic viscosity at
100.degree. C. of 19 cSt. [0078] 20. A (brightstock) residual
aromatic extract commercially available from Shell Pernis Refinery,
Netherlands [0079] 21. 2-stroke performance additive package
containing aminic dispersant, antioxidants (mixed hindered phenols
and aminic antioxidants), over-based detergents from the range
calcium phenates and calcium salicylates [0080] 22. antioxidant
commercially available from CIBA Speciality Chemicals, Berne,
Switzerland
Discussion
[0081] The examples show that a heavy residual GTL base oil (19 cSt
kinematic viscosity at 100.degree. C.) in combination with
polybutylene (PB) gives a better port blocking performance than a
formulation containing solely PB as heavy base stock component,
which demonstrates that heavy residual GTL base oil is an effective
partial polybutylene replacement. In Example 1 the major change in
the formulation compared to Comparative Example A was to reduce PB
and replace with a heavy residual GTL base oil. A minor
modification was made to the API Gp I high viscosity index (HVI)
base stock to maintain iso-viscometrics.
[0082] In Comparative Example B and Examples 2 to 4, it can be seen
that a light GTL base oil (GTL-3) gives an improvement in port
blocking performance compared to an all mineral (API Gp I) analogue
formulation. Further, the Example 4 shows that use of the
combination of light and heavy Fischer-Tropsch base oils, light
Fischer-Tropsch base oil GTL-3 together with heavy Fischer-Tropsch
base oil GTL-19, gives an exceptional improvement in port blocking
performance compared to the standard (API Gp I) mineral oil based
formulation under iso-viscous conditions. Examples 2 to 4 are all 2
stroke oil formulations containing no PB, and yet suitable port
blocking behaviour is obtained.
[0083] In Comparative Examples C and D and Example 5, the standard
2 stroke engine oil formulation, which normally had a polybutylene
content of 35 wt %, was re-formulated to 25 wt % polybutylene in
the formulation together with a replacement amount of a heavy base
stock component. It was noted that there was an improvement in the
port blocking propensity of the 2-stroke formulation, for a range
of heavy base oils, in the order GTL-19> brightstock
(HVI-650)> residual aromatic extract (Flavex 595).
* * * * *