U.S. patent application number 12/294441 was filed with the patent office on 2010-11-11 for lubricant oil additive compositions.
This patent application is currently assigned to Albemarle Corporation. Invention is credited to Vincent J. Gatto, William E. Moehle, Emily R. Schneller.
Application Number | 20100286004 12/294441 |
Document ID | / |
Family ID | 37110316 |
Filed Date | 2010-11-11 |
United States Patent
Application |
20100286004 |
Kind Code |
A1 |
Gatto; Vincent J. ; et
al. |
November 11, 2010 |
LUBRICANT OIL ADDITIVE COMPOSITIONS
Abstract
A lubricant oil composition having a synergistic oxidative
stability is disclosed, the composition comprising at least one
hindered phenolic antioxidant, at least one mono-boronated hindered
phenolic antioxidant, at least one di-boronated hindered phenolic
antioxidant, at least one alkylated diphenylamine and at least one
organomolybdenum compound. The invention also provides a
lubricating oil additive concentrate composition that imparts
synergistic oxidative stability to a lubricant oil upon its
addition, the concentrate composition comprising at least one
hindered phenolic antioxidant, at least one mono-boronated hindered
phenolic antioxidant, at least one di-boronated hindered phenolic
antioxidant, at least one alkylated diphenylamine and at least one
organomolybdenum compound. Further, the concentrate compositions of
the present invention may also be prepared with a high
concentration of hindered phenolic antioxidants without deleterious
effects on viscosity or lubricant solubility.
Inventors: |
Gatto; Vincent J.; (Baton
Rouge, LA) ; Schneller; Emily R.; (Baton Rouge,
LA) ; Moehle; William E.; (Baton Rouge, LA) |
Correspondence
Address: |
ALBEMARLE CORPORATION;PATENT DEPARTMENT
451 FLORIDA STREET
BATON ROUGE
LA
70801
US
|
Assignee: |
Albemarle Corporation
Baton Rouge
LA
|
Family ID: |
37110316 |
Appl. No.: |
12/294441 |
Filed: |
March 28, 2007 |
PCT Filed: |
March 28, 2007 |
PCT NO: |
PCT/US07/65371 |
371 Date: |
September 25, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60787334 |
Mar 29, 2006 |
|
|
|
Current U.S.
Class: |
508/200 |
Current CPC
Class: |
C10N 2030/10 20130101;
C10N 2040/252 20200501; C10N 2040/25 20130101; C10N 2040/255
20200501; C10M 2207/026 20130101; C10M 2215/064 20130101; C10N
2060/14 20130101; C10M 2227/061 20130101; C10N 2010/12 20130101;
C10M 2219/068 20130101; C10M 141/12 20130101 |
Class at
Publication: |
508/200 |
International
Class: |
C10M 169/04 20060101
C10M169/04 |
Claims
1. A lubricant oil composition comprising at least one hindered
phenolic antioxidant, at least one boronated hindered phenolic
antioxidant, at least one alkylated diphenylamine, and at least one
organomolybdenum compound.
2. The lubricant oil composition of claim 1, wherein the at least
one boronated hindered phenolic antioxidant is derived from the at
least one hindered phenolic antioxidant.
3. The lubricant oil composition of claim 2, wherein the at least
one boronated hindered phenolic antioxidant comprises mono- and
di-boronated hindered phenolic antioxidants.
4. The lubricant oil composition of claim 3, wherein the hindered
phenolic antioxidant is
4,4'-methylenebis(2,6-di-tert-butylphenol).
5. The lubricant oil composition of claim 4, wherein the
mono-boronated hindered phenolic antioxidant has the structure
##STR00006## and the di-boronated hindered phenolic antioxidant has
the structure ##STR00007## wherein R.sub.1, R.sub.2, R.sub.3, and
R.sub.4 are independently selected from the group consisting of
linear C.sub.1 to C.sub.8 alkyl groups, branched C.sub.1 to C.sub.8
alkyl groups and cyclic C.sub.3 to C.sub.8 alkyl groups.
6. The lubricant oil composition of claim 5, wherein the at least
one alkylated diphenylamine comprises mono- and di-alkylated
diphenylamine.
7. The lubricant oil composition of claim 6, wherein the
mono-alkylated diphenylamine has the structure ##STR00008## and the
di-alkylated diphenylamine has the structure ##STR00009## wherein
R.sub.1, R.sub.2 and R.sub.3 are independently selected from the
group consisting of linear, branched and cyclic C.sub.4 to C.sub.32
alkyl groups.
8. The lubricant oil composition of claim 7, wherein the mono- and
di-alkylated diphenylamine is selected from the group consisting of
nonylated diphenylamines, octylated diphenylamines, mixed
octylated/styrenated diphenylamines, and mixed butylated/octylated
diphenyl amines.
9. The lubricant oil composition of claim 3, wherein the
organomolybdenum compound is selected from the group consisting of
sulfur-free organomolybdenum compounds, phosphorus-free
organomolybdenum compounds, and sulfur-containing organomolybdenum
compounds.
10. The lubricant oil composition of claim 9, wherein the
organomolybdenum compound is a molybdenum dithiocarbamate having
the structure ##STR00010## wherein R is independently selected from
hydrogen or an alkyl group containing 4 to 18 carbons, and X is
independently selected from oxygen or sulfur.
11. The lubricant oil composition of claim 10, wherein the
concentration of the organomolybdenum compound ranges from about 1
wt % to about 40 wt % of the total concentration of hindered
phenolic, boronated hindered phenolic, alkylated diphenylamine and
organomolybdenum compound.
12. The lubricant oil composition of claim 11, wherein the weight
ratio of molybdenum to boron ranges from about 0.01:1 to about
10:1.
13. The lubricant oil composition of claim 12, wherein the
molybdenum content ranges from between about 50 ppm to about 1000
ppm and the boron content ranges between about 50 ppm to about 500
ppm.
14. The lubricant oil composition of claim 13, wherein the
molybdenum content ranges from between about 100 ppm to about 400
ppm and the boron content ranges between about 100 ppm to about 400
ppm.
15. The lubricant oil composition of claim 4, wherein the
concentration of 4,4'-methylenebis(2,6-di-tert-butylphenol) is
between about 1 to about 50 weight percent of the total
concentration of hindered phenolic, boronated hindered phenolic,
alkylated diphenylamine and organomolybdenum compound.
16. The lubricant oil composition of claim 15, wherein the
concentration of mono- and di-boronated hindered phenolic is
between about 10 to about 80 weight percent of the total
concentration of hindered phenolic, boronated hindered phenolic,
alkylated diphenylamine and organomolybdenum compound.
17. The lubricant oil composition of claim 16, wherein the ratio of
mono-boronated hindered phenolic to di-boronated hindered phenolic
is between about 1:1 to about 1:0.01.
18. The lubricant oil composition of claim 17, wherein the
concentration of alkylated diphenylamine is between about 10 to
about 80 weight percent of the total concentration of hindered
phenolic, boronated hindered phenolic, alkylated diphenylamine, and
organomolybdenum compound.
19. A lubricating oil additive concentrate composition comprising
at least one hindered phenolic antioxidant, at least one boronated
hindered phenolic antioxidant, at least one alkylated
diphenylamine, and at least one organomolybdenum compound.
20. The lubricating oil additive concentrate composition of claim
19, wherein the at least one boronated hindered phenolic
antioxidant is derived from the at least one hindered phenolic
antioxidant.
21. The lubricating oil additive concentrate composition of claim
20, wherein the at least one boronated hindered phenolic
antioxidant comprises mono- and di-boronated hindered phenolic
antioxidants.
22. The lubricating oil additive concentrate composition of claim
21, wherein the hindered phenolic antioxidant is
4,4'-methylenebis(2,6-di-tert-butylphenol).
23. The lubricating oil additive concentrate composition of claim
22, wherein the mono-boronated hindered phenolic antioxidant has
the structure ##STR00011## and the di-boronated hindered phenolic
antioxidant has the structure ##STR00012## wherein R.sub.1,
R.sub.2, R.sub.3, and R.sub.4 are independently selected from the
group consisting of linear C.sub.1 to C.sub.8 alkyl groups,
branched C.sub.1 to C.sub.8 alkyl groups and cyclic C.sub.3 to
C.sub.8 alkyl groups.
24. The lubricating oil additive concentrate composition of claim
23, wherein the at least one alkylated diphenylamine comprises
mono- and di-alkylated diphenylamine.
25. The lubricating oil additive concentrate composition of claim
24, wherein the mono-alkylated diphenylamine has the structure
##STR00013## and the di-alkylated diphenylamine has the structure
##STR00014## wherein R.sub.1, R.sub.2 and R.sub.3 are independently
selected from the group consisting of linear, branched and cyclic
C.sub.4 to C.sub.32 alkyl groups.
26. The lubricating oil additive concentrate composition of claim
25, wherein the mono- and di-alkylated diphenylamine is selected
from the group consisting of nonylated diphenylamines, octylated
diphenylamines, mixed octylated/styrenated diphenylamines, and
mixed butylated/octylated diphenylamines.
27. The lubricant oil composition of claim 21, wherein the
organomolybdenum compound is selected from the group consisting of
sulfur-free organomolybdenum compounds, phosphorus-free
organomolybdenum compounds, and sulfur-containing organomolybdenum
compounds.
28. The lubricant oil composition of claim 27, wherein the
organomolybdenum compound is a molybdenum dithiocarbamate having
the structure ##STR00015## wherein R is independently selected from
hydrogen or an alkyl group containing 4 to 18 carbons, and X is
independently selected from oxygen or sulfur.
29. The lubricant oil composition of claim 28, wherein the
concentration of the organomolybdenum compound ranges from about 1
wt % to about 40 wt % of the total concentration of hindered
phenolic, boronated hindered phenolic, alkylated diphenylamine and
organomolybdenum compound.
30. The lubricating oil additive concentrate composition of claim
22, wherein the concentration of
4,4'-methylenebis(2,6-di-tert-butylphenol) is between about 1 to
about 50 weight percent of the total concentration of hindered
phenolic, boronated hindered phenolic, alkylated diphenylamine and
organomolybdenum compound.
31. The lubricating oil additive concentrate composition of claim
30, wherein the concentration of mono- and di-boronated hindered
phenolic is between about 10 to about 80 weight percent of the
total concentration of hindered phenolic, boronated hindered
phenolic, alkylated diphenylamine and organomolybdenum
compound.
32. The lubricating oil additive concentrate composition of claim
31, wherein the ratio of mono-boronated hindered phenolic to
di-boronated hindered phenolic is between about 1:1 to about
1:0.01.
33. The lubricating oil additive concentrate composition of claim
32, wherein the concentration of alkylated diphenylamine is between
about 10 to about 80 weight percent of the total concentration of
hindered phenolic, boronated hindered phenolic, alkylated
diphenylamine and organomolybdenum compound.
34. The lubricating oil additive concentrate composition of claim
33, further comprising a diluent oil.
35. The lubricating oil additive concentrate composition of claim
34, wherein the concentration of the diluent oil is between about 1
to about 80 wt %.
36. An engine oil composition comprising at least one hindered
phenolic antioxidant, at least one boronated hindered phenolic
antioxidant, at least one alkylated diphenylamine and at least one
organomolybdenum compound.
37. The engine oil composition of claim 36, wherein the hindered
phenolic antioxidant is
4,4'-methylenebis(2,6-di-tert-butylphenol).
38. The engine oil composition of claim 37, wherein the at least
one boronated hindered phenolic antioxidant comprises a
mono-boronated hindered phenolic antioxidant having the structure
##STR00016## and a di-boronated hindered phenolic antioxidant
having the structure ##STR00017## wherein R.sub.1, R.sub.2,
R.sub.3, and R.sub.4 are independently selected from the group
consisting of linear C.sub.1 to C.sub.8 alkyl groups, branched
C.sub.1 to C.sub.8 alkyl groups and cyclic C.sub.3 to C.sub.8 alkyl
groups.
39. The engine oil composition of claim 38, wherein the at least
one alkylated diphenylamine comprises a mono-alkylated
diphenylamine having the structure ##STR00018## and a di-alkylated
diphenylamine having the structure ##STR00019## wherein R.sub.1,
R.sub.2 and R.sub.3 are independently selected from the group
consisting of linear, branched and cyclic C.sub.4 to C.sub.32 alkyl
groups.
40. The engine oil composition of claim 39, wherein the mono- and
di-alkylated diphenylamine is selected from the group consisting of
nonylated diphenylamines, octylated diphenylamines, mixed
octylated/styrenated diphenylamines, and mixed butylated/octylated
diphenylamines.
41. The engine oil composition of claim 40, wherein the
organomolybdenum compound is a molybdenum dithiocarbamate having
the structure ##STR00020## wherein R is independently selected from
hydrogen or an alkyl group containing 4 to 18 carbons, and X is
independently selected from oxygen or sulfur.
42. The engine oil composition of claim 41, wherein the
concentration of 4,4'-methylenebis(2,6-di-tert-butylphenol) is
between about 1 to about 50 weight percent of the total
concentration of hindered phenolic, boronated hindered phenolic,
alkylated diphenylamine and organomolybdenum compound, the
concentration of mono- and di-boronated hindered phenolic is
between about 10 to about 80 weight percent of the total
concentration of hindered phenolic, boronated hindered phenolic,
alkylated diphenylamine and organomolybdenum compound, the ratio of
mono-boronated hindered phenolic to di-boronated hindered phenolic
is between about 1:1 to about 1:0.01, the concentration of
alkylated diphenylamine is between about 10 to about 80 weight
percent of the total concentration of hindered phenolic, boronated
hindered phenolic, alkylated diphenylamine and organomolybdenum
compound, and the concentration of organomolybdenum compound is
between about 1 to about 40 weight percent of the total
concentration of hindered phenolic, boronated hindered phenolic,
alkylated diphenylamine and organomolybdenum compound.
43. The engine oil composition of claim 42, wherein the engine oil
is used to lubricate an engine selected from the group consisting
of a gasoline engine, a heavy duty diesel engine, a natural gas
engine, a marine engine and a railroad engine.
44. An engine oil additive concentrate composition comprising at
least one hindered phenolic antioxidant, at least one boronated
hindered phenolic antioxidant, at least one alkylated diphenylamine
and at least one organomolybdenum compound.
45. The engine oil additive concentrate composition of claim 44,
wherein the hindered phenolic antioxidant is
4,4'-methylenebis(2,6-di-tert-butylphenol).
46. The engine oil additive concentrate composition of claim 45,
wherein the at least one boronated hindered phenolic antioxidant
comprises a mono-boronated hindered phenolic antioxidant having the
structure ##STR00021## and a di-boronated hindered phenolic
antioxidant having the structure ##STR00022## wherein R.sub.1,
R.sub.2, R.sub.3, and R.sub.4 are independently selected from the
group consisting of linear C.sub.1 to C.sub.8 alkyl groups,
branched C.sub.1 to C.sub.8 alkyl groups and cyclic C.sub.3 to
C.sub.8 alkyl groups.
47. The engine oil additive concentrate composition of claim 46,
wherein the at least one alkylated diphenylamine comprises a
mono-alkylated diphenylamine having the structure ##STR00023## and
a di-alkylated diphenylamine having the structure ##STR00024##
wherein R.sub.1, R.sub.2 and R.sub.3 are independently selected
from the group consisting of linear, branched and cyclic C.sub.4 to
C.sub.32 alkyl groups.
48. The engine oil additive concentrate composition of claim 47,
wherein the mono- and di-alkylated diphenylamine is selected from
the group consisting of nonylated diphenylamines, octylated
diphenylamines, mixed octylated/styrenated diphenylamines, and
mixed butylated/octylated diphenylamines.
49. The engine oil additive concentrate composition of claim 48,
wherein the organomolybdenum compound is a molybdenum
dithiocarbamate having the structure ##STR00025## wherein R is
independently selected from hydrogen or an alkyl group containing 4
to 18 carbons, and X is independently selected from oxygen or
sulfur.
50. The engine oil additive concentrate composition of claim 49,
wherein the concentration of
4,4'-methylenebis(2,6-di-tert-butylphenol) is between about 1 to
about 50 weight percent of the total concentration of hindered
phenolic, boronated hindered phenolic, alkylated diphenylamine and
organomolybdenum compound, the concentration of mono- and
di-boronated hindered phenolic is between about 10 to about 80
weight percent of the total concentration of hindered phenolic,
boronated hindered phenolic, alkylated diphenylamine and
organomolybdenum compound, the ratio of mono-boronated hindered
phenolic to di-boronated hindered phenolic is between about 1:1 to
about 1:0.01, the concentration of alkylated diphenylamine is
between about 10 to about 80 weight percent of the total
concentration of hindered phenolic, boronated hindered phenolic,
alkylated diphenylamine and organomolybdenum compound, and the
concentration of organomolybdenum compound is between about 1 to
about 40 weight percent of the total concentration of hindered
phenolic, boronated hindered phenolic, alkylated diphenylamine and
organomolybdenum compound.
51. The engine oil additive concentrate composition of claim 50,
wherein the engine oil is used to lubricate an engine selected from
the group consisting of a gasoline engine, a heavy duty diesel
engine, a natural gas engine, a marine engine and a railroad
engine.
52. A method of increasing the concentration of at least one
hindered phenolic antioxidant in a lubricant oil additive
concentrate composition, the method comprising the step of adding
at least one boronated hindered phenolic antioxidant to the
lubricant oil additive concentrate.
Description
FIELD OF THE INVENTION
[0001] The invention relates to lubricant oil additive compositions
and lubricating oil compositions containing the same. More
particularly, this invention relates to combinations of hindered
phenolic antioxidants, boronated hindered phenolic antioxidants,
alkylated diphenylamines and organomolybdenum compounds useful as
lubricant oil compositions and lubricating oil additive
compositions.
DESCRIPTION OF RELATED ART
[0002] Hindered phenolic and boronated hindered phenolics are well
known in the art, including large molecular phenolics incorporating
the moiety, 2,6-di-tert-butylphenol, and the like. See, for
example, the following US and foreign patents: U.S. Pat. No.
4,927,553; U.S. Pat. No. 3,356,707; U.S. Pat. No. 3,509,054; U.S.
Pat. No. 3,347,793; U.S. Pat. No. 3,014,061; U.S. Pat. No.
3,359,298; U.S. Pat. No. 2,813,830; U.S. Pat. No. 2,462,616; GB
864,840; U.S. Pat. No. 5,698,499; U.S. Pat. No. 5,252,237; US RE
32,295; U.S. Pat. No. 4,547,302; U.S. Pat. No. 3,211,652; and U.S.
Pat. No. 2,807,653
[0003] The use of alkylated diphenylamine as an antioxidant
additive in lubricating oil formulations is also well known in the
art. See, for example, the following US patents: U.S. Pat. No.
5,620,948; U.S. Pat. No. 5,595,964; U.S. Pat. No. 5,569,644; U.S.
Pat. No. 4,857,214; U.S. Pat. No. 4,455,243; and U.S. Pat. No.
5,759,965.
[0004] There are many examples in the patent literature showing the
use of molybdenum additives as antioxidants, deposit control
additives, anti-wear additives and friction modifiers. See, for
example, the following US and foreign patents: U.S. Pat. No.
5,840,672; U.S. Pat. No. 5,814,587; U.S. Pat. No. 4,529,526; WO
95/07966; U.S. Pat. No. 5,650,381; U.S. Pat. No. 4,812,246; U.S.
Pat. No. 5,458,807; WO 95/07964; U.S. Pat. No. 5,880,073; U.S. Pat.
No. 5,658,862; U.S. Pat. No. 5,696,065; WO 95/07963; U.S. Pat. No.
5,665,684; U.S. Pat. No. 4,360,438; U.S. Pat. No. 5,736,491; WO
95/27022; U.S. Pat. No. 5,786,307; U.S. Pat. No. 4,501,678; U.S.
Pat. No. 5,688,748; EP 0 447 916 A1; U.S. Pat. No. 5,807,813; U.S.
Pat. No. 4,692,256; U.S. Pat. No. 5,605,880; WO 95/07962; U.S. Pat.
No. 5,837,657; U.S. Pat. No. 4,832,867; U.S. Pat. No. 4,705,641; EP
0 768 366 A1; U.S. Pat. No. 6,103,674; U.S. Pat. No. 6,010,987;
U.S. Pat. No. 6,110,878; EP 1 136 496 A1; U.S. Pat. No. 6,150,309;
U.S. Pat. No. 6,232,276; U.S. Pat. No. 6,306,802; EP 1 136 497 A1;
U.S. Pat. No. 5,888,945; U.S. Pat. No. 6,187,723; U.S. Pat. No.
6,117,826; U.S. Pat. No. 6,103,674; U.S. Pat. No. 6,063,741; U.S.
Pat. No. 6,017,858; U.S. Pat. No. 5,994,277; and U.S. Pat. No.
6,174,842.
SUMMARY OF THE INVENTION
[0005] The present invention generally provides a lubricant oil
composition having improved oxidative stability, the composition
comprising at least one hindered phenolic antioxidant, at least one
mono-boronated hindered phenolic antioxidant, at least one
di-boronated hindered phenolic antioxidant, at least one alkylated
diphenylamine, and at least one organomolybdenum compound. The
invention also provides a lubricating oil additive concentrate
composition that imparts synergistic oxidative stability to a
lubricant oil upon its addition, the concentrate composition
comprising at least one hindered phenolic antioxidant, at least one
mono-boronated hindered phenolic antioxidant, at least one
di-boronated hindered phenolic antioxidant, at least one alkylated
diphenylamine, and at least one organomolybdenum compound. Further,
the concentrate compositions of the present invention may also be
prepared with a high concentration of hindered phenolic
antioxidants without deleterious effects on viscosity or lubricant
solubility.
[0006] The synergistic improvement of oxidative stability in
lubricant oil compositions and lubricating oil additive concentrate
compositions comprising at least one hindered phenolic antioxidant,
at least one mono-boronated hindered phenolic antioxidant, at least
one di-boronated hindered phenolic antioxidant, and at least one
alkylated diphenylamine is disclosed in concurrently filed,
commonly owned U.S. Provisional Application 60/758,754 filed on
Jan. 13, 2006, and in PCT application number PCT/US2007/060489 that
claims priority to U.S. Provisional Application 60/758,754, both of
which are hereby incorporated by reference in their entirety to the
extent allowed by applicable law. The present invention improves
upon the disclosure of U.S. Provisional Application 60/758,754 such
that lubricant oil compositions and lubricating oil additive
concentrate compositions comprising at least one hindered phenolic
antioxidant, at least one mono-boronated hindered phenolic
antioxidant, at least one di-boronated hindered phenolic
antioxidant, at least one alkylated diphenylamine, and at least one
organomolybdenum compound exhibits improved oxidative stability
compared to conventional formulations.
[0007] In one aspect, a lubricant oil or lubricating oil additive
concentrate composition comprising: (a)
4,4'-methylenebis(2,6-di-tert-butylphenol), (b)
4,4'-methylenebis(2,6-di-tert-butylphenol)-mono-(di-alkyl
orthoborate), (c)
4,4'-methylenebis(2,6-di-tert-butylphenol)-di-(di-alkyl
orthoborate), (d) an alkylated diphenylamine, and (e) an
organomolybdenum compound, is an effective antioxidant combination
for use in lubricants.
[0008] In another aspect, a lubricant oil or lubricating oil
additive concentrate composition comprising: (a) a hindered
phenolic antioxidant, (b) either a single or multiple ortho-borate
ester, or combinations thereof, derived from a hindered phenolic
antioxidant, wherein the boron is attached to the hindered phenolic
oxygen, (c) an alkylated diphenylamine, and (d) an organomolybdenum
compound, is an effective antioxidant combination for use in
lubricants.
BRIEF DESCRIPTION OF THE FIGURE
[0009] FIG. 1 shows graphical results from Example A.
DETAILED DESCRIPTION OF THE INVENTION
[0010] Hindered phenolics suitable for use in the compositions of
the present invention include phenolics incorporating the
2,6-di-tert-butylphenol moiety. A suitable hindered phenolic, which
is commercially sold by Albemarle Corporation.TM. under the trade
name Ethanox.RTM. 702, is
4,4'methylenebis(2,6-di-tert-butylphenol), hereinafter referred to
as MBDTBP, having the structure of Structure I below:
##STR00001##
[0011] Other suitable hindered phenolics include,
2,4-di-tert-butylphenol, 2,6-di-tert-butylphenol,
6-tert-butyl-ortho-cresol, 2,6-di-isopropylphenol,
2,4-di-sec-butylphenol, higher molecular weight hindered phenolic
antioxidants derived synthetically from 2,4-di-tert-butylphenol,
2,6-di-tert-butylphenol, 6-tert-butyl-ortho-cresol,
2,6-di-isopropylphenol, or 2,4-di-sec-butylphenol, butylated
hydroxy toluene (BHT), and the like.
[0012] The amount of hindered phenolic present in the compositions
of the invention ranges from about 1 to about 50 weight percent of
the total concentration of hindered phenolic, boronated hindered
phenolic, and alkylated diphenylamine. In additional aspects the
amount of hindered phenolic present in the compositions of the
invention ranges from about 1 to about 40 weight percent, about 1
to about 30 weight percent, about 1 to about 25 weight percent,
about 1 to about 20 weight percent, and about 1 to about 15 weight
percent of the total concentration of hindered phenolic, boronated
hindered phenolic, and alkylated diphenylamine.
[0013] The mono- and di-boronated hindered phenolics suitable for
use in the compositions of the present invention are derived from
the hindered phenolics described above by reaction with tri-alkyl
orthoborates. One such process is disclosed in U.S. Pat. No.
4,927,553. In one aspect, suitable mono- and di-boronated hindered
phenolics have the structures of Structures II and III below:
##STR00002##
wherein R.sub.1, R.sub.2, R.sub.3, and R.sub.4 are independently
selected from the group consisting of linear, branched and cyclic
C.sub.1 to C.sub.8 alkyl groups. Examples of such groups include,
but are not limited to, methyl, ethyl, n-propyl, iso-propyl,
n-butyl, sec-butyl, iso-butyl, n-pentyl, 2-methylbutyl,
3-methylbutyl, 2-methyl-2-butyl, 3-methyl-2-butyl, isopentyl,
n-hexyl, cyclopentyl, cyclohexyl, 2-ethylbutyl, 2-methylpentyl,
3-methylpentyl, 4-methylpentyl, 3-methyl-2-pentyl, 4-methyl-2
pentyl, 3-methyl-3-pentyl, 3,3-dimethylbutyl, 3,3-dimethyl-2-butyl,
2,3-dimethyl-2-butyl, 2-methyl-2-hexyl, 2,2-dimethyl-3-pentyl,
2-heptyl, 3-heptyl, 2-methyl-3-hexyl, 3-ethyl-3-pentyl,
2,3-dimethyl-3-pentyl, 2,4-dimethyl-3-pentyl, 5-methyl-2-hexyl,
4,4-dimethyl-2-pentyl, 5-methylhexyl, n-heptyl, n-octyl, iso-octyl,
2-ethylhexyl, 2-propylpentyl, 2-octyl, 3-octyl,
2,44-trimethylpentyl, 4-methyl-3-heptyl and 6-methyl-2-heptyl.
[0014] Other mono- and di-boronated hindered phenolics may be
derived from reacting the specific hindered phenolics described
above, or mixtures of hindered phenolics, with tri-alkyl
orthoborates.
[0015] The combined total of mono- and di-boronated hindered
phenolics present in the compositions of the invention ranges from
about 10 to about 80 weight percent of the total concentration of
hindered phenolic, boronated hindered phenolic, and alkylated
diphenylamine. The ratio of mono-boronated hindered phenolic to
di-boronated hindered phenolic may vary from about 0.01:1 to about
1:0.01. The amount of mono-boronated hindered phenolic can be
approximately equal to or greater than that of di-boronated
hindered phenolic.
[0016] The amount of MBDTBP in conventional lubricant oil additive
concentrate compositions has been limited by its solubility to
about 10 wt % of the total additive concentrate. However, the
present invention provides a method for increasing the
concentration of hindered phenolic antioxidant in the lubricant oil
additive concentrate composition to be increased to as high as
about 50 wt % by including boronated hindered phenolic antioxidants
in the lubricant oil additive concentrate composition.
[0017] The alkylated diphenylamines suitable for use in the
compositions of the present invention are prepared from
diphenylamine by reaction with olefins. One particularly useful
method of preparing alkylated diphenylamines is described in US
Patent Publication US-2006-0276677-A1 (which related to U.S. Ser.
No. 11/442,856 filed 30 May 2006, which claims priority to U.S.
Provisional Patent Application 60/687,182 filed on Jun. 2, 2005 and
to U.S. Provisional Patent Application 60/717,322 filed on Sep. 14,
2005), which US Patent Publication is incorporated in its entirety
by reference herein to the extent allowed by applicable law. Both
mono- and di-alkylated diphenylamines may be employed, either alone
are in combination, and have the structures shown in Structures IV
and V below:
##STR00003##
wherein R.sub.1, R.sub.2 and R.sub.3 are independently selected
from the group consisting of linear, branched and cyclic C.sub.4 to
C.sub.32 alkyl groups. Examples of such groups include, but are not
limited to, alkyl groups derived from linear alpha-olefins,
isomerized alpha-olefins polymerized alpha-olefins, low molecular
weight oligomers of propylene, and low molecular weight oligomers
of isobutylene. Specific examples include but are not limited to
butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl,
dodecyl, tridecyl, tetradecyl, dipropyl, tripropyl, tetrapropyl,
pentapropyl, hexapropyl, heptapropyl, octapropyl, diisobutyl,
triisobutyl, tetraisobutyl, pentaisobutyl, hexaisobutyl, and
heptaisobutyl.
[0018] The combined total of mono- and di-alkylated diphenylamine
present in the compositions of the invention ranges from about 10
to about 80 weight percent of the total concentration of hindered
phenolic, boronated hindered phenolic, and alkylated diphenylamine.
The ratio of mono- to di-alkylated diphenylamine may vary from
about 0.01:1 to about 1:0.01.
[0019] Examples of suitable alkylated diphenylamines are nonylated
diphenylamines (NDPA), octylated diphenylamines, mixed
octylated/styrenated diphenylamines (such as Durad.RTM. AX55), and
mixed butylated/octylated diphenylamines (such as Vanlube.RTM.
961). Further, the nitrogen content of the alkylated diphenylamines
can be in the range of about 2.0 to about 6.0 wt. %. Lower levels
of nitrogen dilute the effectiveness of the alkylated
diphenylamines while higher levels of nitrogen may adversely impact
compatibility of the alkylated diphenylamines in the lubricant or
the lubricant's volatility. The alkylated diphenylamines can be a
liquid or low melting solid.
[0020] Organomolybdenum compounds suitable for use in the present
invention include sulfur-free compounds, phosphorus-free compounds,
and sulfur-containing compounds. The molybdenum content of
organomolybdenum compounds may vary from about 1 wt % to about 15
wt %. The concentration of the organomolybdenum compound may range
from about 1 wt % to about 40 wt % of the total concentration of
hindered phenolic, boronated hindered phenolic, alkylated
diphenylamine and organomolybdenum compound.
[0021] The amount of organomolybdenum compound used in compositions
of the present invention is such that the weight ratio of
molybdenum to boron ranges from about 0.01:1 to about 10:1. The
molybdenum content of a lubricant oil can range from between about
50 to about 1000 ppm and the boron content can range between about
50 to about 500 ppm. The molybdenum content of a lubricant oil can
range from between about 100 to about 400 ppm and the boron content
can range between about 100 to about 400 ppm.
[0022] Sulfur- and phosphorus-free organomolybdenum compounds may
be prepared by reacting a sulfur and phosphorus-free molybdenum
source with an organic compound containing amino and/or alcohol
groups. Examples of sulfur- and phosphorus-free molybdenum sources
include molybdenum trioxide, ammonium molybdate, sodium molybdate
and potassium molybdate. The amino groups may be monoamines,
diamines, or polyamines. The alcohol groups may be mono-substituted
alcohols, diols or bis-alcohols, or polyalcohols. As an example,
the reaction of diamines with fatty oils produces a product
containing both amino and alcohol groups that can react with the
sulfur- and phosphorus-free molybdenum source.
[0023] Examples of sulfur- and phosphorus-free organomolybdenum
compounds suitable for use in the present invention include the
following: compounds prepared by reacting certain basic nitrogen
compounds with a molybdenum source as defined in U.S. Pat. Nos.
4,259,195 and 4,261,843; compounds prepared by reacting a
hydrocarbyl substituted hydroxy alkylated amine with a molybdenum
source as defined in U.S. Pat. No. 4,164,473; compounds prepared by
reacting a phenol aldehyde condensation product, a mono-alkylated
alkylene diamine, and a molybdenum source as defined in U.S. Pat.
No. 4,266,945; compounds prepared by reacting a fatty oil,
diethanolamine, and a molybdenum source as defined in U.S. Pat. No.
4,889,647; compounds prepared by reacting a fatty oil or acid with
2-(2-aminoethyl)aminoethanol, and a molybdenum source as defined in
U.S. Pat. No. 5,137,647; compounds prepared by reacting a secondary
amine with a molybdenum source as defined in U.S. Pat. No.
4,692,256; compounds prepared by reacting a diol, diamino, or
amino-alcohol compound with a molybdenum source as defined in U.S.
Pat. No. 5,412,130; compounds prepared by reacting a fatty oil,
mono-alkylated alkylene diamine, and a molybdenum source as defined
in European Patent Application EP 1 136 496 A1; and compounds
prepared by reacting a fatty acid, mono-alkylated alkylene diamine,
glycerides, and a molybdenum source as defined in European Patent
Application EP 1 136 497 A1.
[0024] Examples of commercial sulfur- and phosphorus-free oil
soluble molybdenum compounds are Sakura-Lube 700 from Asahi Denka,
and Molyvan 856B and Molyvan 855 from R. T. Vanderbilt Company,
Inc.
[0025] Molybdenum compounds prepared by reacting a fatty oil,
diethanolamine, and a molybdenum source as defined in U.S. Pat. No.
4,889,647 are sometimes illustrated as having one or both of the
following structures,
##STR00004##
wherein R is a fatty alkyl chain. The exact chemical structure of
these materials is not fully known and may in fact be
multi-component mixtures of many organomolybdenum compounds.
[0026] Sulfur-containing organomolybdenum compounds may be prepared
by a variety of methods. One method involves reacting a sulfur and
phosphorus-free molybdenum source with an amino group and one or
more sulfur sources. Sulfur sources include carbon disulfide,
hydrogen sulfide, sodium sulfide and elemental sulfur.
Alternatively, the sulfur-containing molybdenum compound may be
prepared by reacting a sulfur containing molybdenum source with an
amino group or thiuram group and optionally a second sulfur source.
Examples of sulfur- and phosphorus-free molybdenum sources include
molybdenum trioxide, ammonium molybdate, sodium molybdate,
potassium molybdate and molybdenum halides. The amino groups may be
monoamines, diamines, or polyamines. As an example, the reaction of
molybdenum trioxide with a secondary amine and carbon disulfide
produces molybdenum dithiocarbamates. Alternatively, the reaction
of (NH.sub.4)2Mo.sub.3S.sub.13.n(H.sub.2O) where n varies between 0
to 2 with a tetralkylthiuram disulfide produces a trinuclear
sulfur-containing molybdenum dithiocarbamate.
[0027] Examples of sulfur-containing organomolybdenum compounds
suitable for use in the present invention include the following:
compounds prepared by reacting molybdenum trioxide with a secondary
amine and carbon disulfide as defined in U.S. Pat. Nos. 3,509,051
and 3,356,702; compounds prepared by reacting a sulfur-free
molybdenum source with a secondary amine, carbon disulfide, and an
additional sulfur source as defined in U.S. Pat. No. 4,098,705;
compounds prepared by reacting a molybdenum halide with a secondary
amine and carbon disulfide as defined in U.S. Pat. No. 4,178,258;
compounds prepared by reacting a molybdenum source with a basic
nitrogen compound and a sulfur source as defined in U.S. Pat. Nos.
4,263,152, 4,265,773, 4,272,387, 4,285,822, 4,369,119, and
4,395,343; compounds prepared by reacting ammonium
tetrathiomolybdate with a basic nitrogen compound as defined in
U.S. Pat. No. 4,283,295; compounds prepared by reacting an olefin,
sulfur, an amine and a molybdenum source as defined in U.S. Pat.
No. 4,362,633; compounds prepared by reacting ammonium
tetrathiomolybdate with a basic nitrogen compound and an organic
sulfur source as defined in U.S. Pat. No. 4,402,840; compounds
prepared by reacting a phenolic compound, an amine and a molybdenum
source with a sulfur source as defined in U.S. Pat. No. 4,466,901;
compounds prepared by reacting a triglyceride, a basic nitrogen
compound, a molybdenum source, and a sulfur source as defined in
U.S. Pat. No. 4,765,918; compounds prepared by reacting alkali
metal alkylthioxanthate salts with molybdenum halides as defined in
U.S. Pat. No. 4,966,719; compounds prepared by reacting a
tetralkylthiuram disulfide with molybdenum hexacarbonyl as defined
in U.S. Pat. No. 4,978,464; compounds prepared by reacting an alkyl
dixanthogen with molybdenum hexacarbonyl as defined in U.S. Pat.
No. 4,990,271; compounds prepared by reacting alkali metal
alkylxanthate salts with dimolybdenum tetra-acetate as defined in
U.S. Pat. No. 4,995,996; compounds prepared by reacting
(NH.sub.4)2Mo.sub.3S.sub.13.2(H.sub.2O) with an alkali metal
dialkyldithiocarbamate or tetralkyl thiuram disulfide as define in
U.S. Pat. No. 6,232,276; compounds prepared by reacting an ester or
acid with a diamine, a molybdenum source and carbon disulfide as
defined in U.S. Pat. No. 6,103,674; and compounds prepared by
reacting an alkali metal dialkyldithiocarbamate with
3-chloropropionic acid, followed by molybdenum trioxide, as defined
in U.S. Pat. No. 6,117,826.
[0028] Examples of commercial sulfur-containing oil soluble
molybdenum compounds are Sakura-Lube.RTM. 100, Sakura-Lube.RTM.
155, Sakura-Lube.RTM. 165, and Sakura-Lube.RTM. 180 from Asahi
Denka Kogyo K. K., Molyvan.RTM. A, Molyvan.RTM. 807 and
Molyvan.RTM. 822 from R. T. Vanderbilt Company, and Naugalube.RTM.
MolyFM from Crompton Corporation.
[0029] Molybdenum dithiocarbamates are suitable organomolybdenum
compounds and have the following structure:
##STR00005##
wherein R is independently selected from hydrogen or an alkyl group
containing 4 to 18 carbons, and X is independently selected from
oxygen or sulfur.
[0030] The lubricating oil may be any basestock or base oil
(characterized as Group I, Group II, Group III, Group IV or Group V
as defined by the API basestock classification system), or
lubricant composed predominately of aromatics, naphthenics,
paraffinics, poly-alpha-olefins and/or synthetic esters. Further,
the lubricant may also contain additional additives so as to make
the system acceptable for use in a variety of applications. These
additives include dispersants, detergents, viscosity index
improvers, pour point depressants, anti-wear additives, extreme
pressure additives, friction modifiers, corrosion inhibitors, rust
inhibitors, emulsifiers, demulsifiers, anti-foaming agents,
colorants, seal swelling agents, and additional antioxidants.
[0031] The present invention may be useful in passenger car engine
oils, heavy duty diesel oils, medium speed diesel oils, railroad
oils, marine engine oils, natural gas engine oils, 2-cycle engine
oils, steam turbine oils, gas turbine oils, combined cycle turbine
oils, R&O oils, industrial gear oils, automotive gear oils,
compressor oils, manual transmission fluids, automatic transmission
fluids, slideway oils, quench oils, flush oils and hydraulic
fluids. Suitable applications are in engine oils. A suitable
application is in low phosphorus engine oils characterized by a
phosphorus content of less than 1000 ppm.
[0032] The lubricating oil additive concentrate may or may not
contain a diluent oil. If a diluent oil is used, the diluent oil is
typically present between 1 and 80 wt. % of the concentrate.
[0033] Typically, the total amount of hindered phenolic, boronated
hindered phenolic, alkylated diphenylamine, and organomolybdenum
compound that are added to fully formulated oils depends upon the
end use application. For example, in a turbine oil the total amount
of hindered phenolic, boronated hindered phenolic, alkylated
diphenylamine, and organomolybdenum compound added to the oil
ranges between about 0.05 and about 1.0 wt. %. In contrast, in an
engine oil the total amount of hindered phenolic, boronated
hindered phenolic, alkylated diphenylamine and organomolybdeum
compound added to the oil ranges between about 0.2 and about 3.0
wt. %. In ultra-low phosphorus engine oils the total amount of
hindered phenolic, boronated hindered phenolic, and alkylated
diphenylamine may approach 5.0 wt. % or more.
[0034] An example of a lubricating oil additive concentrate in
accordance with the present invention is as follows: [0035] (a)
4,4-methylenebis(2,6-di-tert-butylphenol) @ 10 wt. %; [0036] (b)
4,4'-methylenebis(2,6-di-tert-butylphenol) mono-(di-sec-butyl
orthoborate) and 4,4'-methylenebis(2,6-di-tert-butylphenol)
di-(di-sec-butyl orthoborate) @ 40 wt. %; [0037] (c)
dinonyldiphenylamine and monononyldiphenylamine @ 10 wt. %; [0038]
(d) a molybdenum dithiocarbamate containing 4.5 wt. % molybdenum @
20 wt. %; and [0039] (e) paraffinic diluent oil @ 20 wt. %.
[0040] An example of a low phosphorus engine oil in accordance with
the present invention is as follows: [0041] (a)
4,4-methylenebis(2,6-di-tert-butylphenol) @ 0.5 wt. %; [0042] (b)
4,4'-methylenebis(2,6-di-tert-butylphenol) mono-(di-sec-butyl
orthoborate) and 4,4'-methylenebis(2,6-di-tert-butylphenol)
di-(di-sec-butyl orthoborate) @ 1.0 wt. %; [0043] (c)
dinonyldiphenylamine and monononyldiphenylamine @ 0.75 wt. %;
[0044] (d) a molybdenum dithiocarbamate containing 4.5 wt. %
molybdenum @ 0.2 wt. % [0045] (e) a dispersant concentrate @ 4.8
wt. %; [0046] (f) an overbased calcium detergent concentrate @ 1.8
wt. %; [0047] (g) a neutral calcium detergent concentrate @ 0.5 wt.
%; [0048] (h) zinc dialkyldithiophosphate @ 0.6 weight %; [0049]
(i) a pour point depressant at 0.1 wt. %; [0050] (j) a viscosity
index improver concentrate @ 8.0 wt. %; [0051] (k) an organic
friction modifier @ 0.5 wt. %; and [0052] (l) paraffinic
lubricating oil @ 81.25 wt. %
Example A
Oil Thickening and Oxidation at Elevated Temperatures
[0053] A passenger car engine oil preblend was prepared in
accordance with the present invention by blending the following
materials: [0054] (a) 5.000 wt. % of an ashless dispersant; [0055]
(b) 1.875 wt. % of an overbased detergent containing calcium;
[0056] (c) 0.521 wt. % of a neutral detergent containing calcium;
[0057] (d) 0.625 wt. % of a secondary zinc dialkyldithiophosphate;
and [0058] (e) 91.979 wt. % of a 150N Group II baseoil. To this
engine oil preblend was added the components indicated in Table
1.
TABLE-US-00001 [0058] TABLE 1 Components of Examples A.1-A.6.
Engine Oil Ex. Example Preblend HPE NDPA BMBDTBP MoDTC G2BO Total
No. Type (wt %) (wt %) (wt %) (wt %) (wt %, ppm Mo) (wt %) (wt %)
A.1 Comparative 96.00 1.00 0.75 0.4, 225 1.85 100.00 A.2
Comparative 96.00 1.25 0.75 0.4, 225 1.60 100.00 A.3 Invention
96.00 0.50 1.00 0.4, 225 2.10 100.00 A.4 Invention 96.00 0.75 1.00
0.4, 225 1.85 100.00 A.5 Invention 96.00 0.75 0.75 0.4, 225 2.10
100.00 A.6 Invention 96.00 0.75 1.25 0.4, 225 1.60 100.00 MoDTC =
Molybdenum dithiocarbamate containing 4.5 wt. % molybdenum BMBDTBP
= a sample composed of: 15.6 wt. %
4,4-methylenebis(2,6-di-tert-butylphenol, 38.6 wt. %
4,4'-methylenebis(2,6-di-tert-butylphenol)-mono-(di-sec-butyl
orthoborate), 17.4 wt. %
4,4'-methylenebis(2,6-di-tert-butylphenol)-di-(di-sec-butyl
orthoborate) (values calculated based upon HPLC analysis), 1.0 wt.
% of an ashless dispersant, and 29.0 wt. % of a 500N naphthenic
diluent oil. The sample has a boron content of 1.23 wt % as
determined by ICP. HPE = 3,5-di-tert-butyl-4-hydroxyhydrocinnamic
acid, C.sub.7-C.sub.9branched alkyl esters NDPA = Nonylated
diphenylamine G2BO = 150N Group II baseoil
[0059] The oxidative stability of these finished engine oils was
evaluated in a bulk oil oxidation test. Each oil (300 mL) was
treated with an iron naphthenate oxidation catalyst to deliver 110
ppm of iron to the finished oil. The oils were heated in a block
heater at 150.degree. C., while 10 liters/hour of dry oxygen was
bubbled through the oil. Samples of the oxidized oils were removed
at 24, 48, 72, 96, 120, 144, 168 and 192 hours. Kinematic
viscosities of each sample were determined at 40.degree. C. The
percent viscosity increase of the oxidized oil versus the fresh oil
was calculated. The percent viscosity increase results are shown in
Table 2.
TABLE-US-00002 TABLE 2 Percent viscosity increase of finished oils
A.1-A.6 in bulk oil oxidation test. Sample 0 24 48 72 96 120 144
168 192 A.1 0 2.5 3.5 5.1 33.5 172.4 696.8 (comparative) A.2 0 2.9
4 7.9 100.0 382.1 (comparative) A.3 (invention) 0 0.3 1.3 2.4 3.4
15.4 148.3 716.6 A.4 (invention) 0 0.8 1.9 2.8 3.3 4.3 6.9 50.6
283.0 A.5 (invention) 0 0.2 1.2 2.1 2.4 3.5 4.7 13.9 153.8 A.6
(invention) 0 0.9 2.4 3.4 4.4 5.3 8.0 49.4 290.7
[0060] A higher percent viscosity increase is a measure of
increased oxidation and degradation of the lubricant. These results
clearly show that the inventive antioxidant combination in Examples
A.3 to A.6 provide superior oxidation protection compared to the
other Examples (A.1-A.2). Antioxidant systems that do not contain
the combination of 4,4'-methylenebis(2,6-di-tert-butylphenol),
boronated 4,4'-methylenebis(2,6-di-tert-butylphenol), nonylated
diphenylamine and organomolybdenum compound show poor oxidation
control while systems containing BMBDTBP, NDPA and MoDTC show
superior oxidative control. These results are shown graphically in
FIG. 1.
Example B
Pressurized Differential Scanning Calorimetry (PDSC)
[0061] The oxidative stability of the finished engine oils prepared
in Example A was evaluated using pressurized differential scanning
calorimetry following the ASTM standard test method D 6186 and
using the following operation conditions: isothermal
temperature=180.degree. C., oxygen gas @ 500 psig with a flow rate
of 100 mL/min, approximately 3 mg sample size, open aluminum pans.
Each oil was treated with an iron naphthenate oxidation catalyst to
deliver 55 ppm of iron to the finished oil. Oxidation induction
times (OIT) were determined according to the ASTM method. Each oil
was tested in duplicate and the results averaged. The OIT results
are shown in Table 3.
TABLE-US-00003 TABLE 3 Oxidation Induction Times in minutes for
finished oils A.1-A.6 tested using PDSC. Sample ID OIT OIT AVG. A.1
109.48 119.12 114.30 A.2 112.33 109.2 110.77 A.3 111.09 113.15
112.12 A.4 156.44 147.78 152.11 A.5 143.68 146.24 145.96 A.6 146.67
147.36 147.02
[0062] A longer induction time is a measure of increased oxidation
stability of the lubricant. These results clearly show that the
inventive antioxidant combination in Examples A.4 to A.6 provide
superior oxidation protection compared to the non-inventive
Examples (A.1-A.2). Antioxidant systems that do not contain the
combination of 4,4'-methylenebis(2,6-di-tert-butylphenol),
boronated 4,4'-methylenebis(2,6-di-tert-butylphenol), nonylated
diphenylamine and molybdenum show poor oxidation control while
systems containing BMDTBP, NDPA and MoDTC show superior oxidative
control. Also, considerably less, i.e. 25% less, antioxidant is
used in inventive oil A.3 versus non-inventive oil A.2 in order to
deliver the same performance level in the PDSC (112.12 minutes and
110.77 minutes statistically equivalent).
[0063] While the compositions and methods of this invention have
been described in terms of preferred embodiments, it will be
apparent to those of skill in the art that variations may be
applied to the compositions, methods and/or processes and in the
steps or in the sequence of steps of the methods described herein
without departing from the concept and scope of the invention. More
specifically, it will be apparent that certain agents which are
both chemically and physiologically related may be substituted for
the agents described herein while the same or similar results would
be achieved. All such similar substitutes and modifications
apparent to those skilled in the art are deemed to be within the
scope and concept of the invention.
* * * * *