Note: Descriptions are shown in the official language in which they were submitted.
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NON-HALOGENATED METAL CONDITIONER
AND EXTREME PRESSURE LUBRICANT
FIELD OF THE INVENTION
The herein disclosed invention finds applicability in the field of extreme
pressure
lubrication. Examples of areas needing this type of lubrication are machinery
in general and
particularly refrigeration and air-conditioning systems, heat pumps and
compressors wherein
the lubricant is added to circulate in the compressor system reservoir and
beaxing surfaces,
etc.
BACKGROUND OF THE INVENTION
There is a need in industry for a lubricating and/or conditioning system for
lubricating
metal surfaces, especially in refrigeration and air conditioning systems. It
is desirable that the
lubricating system be free of chlorine, sulfur, and fluorine which have the
potential of
combining with hydrogen to produce hydrochloric, sulfuric, and hydrofluoric
acid,
respectively.
In the field of specialty lubrication, active elements such as sulfur,
chlorine, fluorine,
lead, etc. have been used to provide extreme pressure (EP), anti-wear, anti-
friction properties.
In this era of increased environmental concerns, the use of these types of
elements, regardless
of their ability to improve lubrication performance, adds to the hazardous
waste stream and
increases the cost of production if used in industry.
In some cases, chemical compound break-down can release the element to form
other
compounds which are corrosive, such as sulfuric acid, hydrochloric acid, etc.
Prior Art U. S. Patents
Wilkins, et al (4,963,280) teaches compositions for improving the efficiency
of heat
pumps, refrigeration units, air condition and heating units. The patentees do
this by
employing a polar organic compound which is defined as being an organic
compound
containing sufficient polar groups to provide regions on the molecule which
have regions of
high electron densities and other regions which have low electron densities.
The preferred
polar compounds are liquid halogenated a-olefins and liquid halogenated
paraffms.
Ka~ol, et al (5,576,273) teaches a synergistic mixture of a dithiocarbamate
and
organic bismuth compounds to have good extreme pressure properties and to be
useful in
lubricating compositions.
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Ifarol et al (5,631,214) teaches the preparation of bismuth dithiocarbamates
for use as
extreme pressure additives.
Sgarbi, et al (6,276,147) teaches a polar solution for air conditioning and
refrigeration
containing a dithiocarbarnate and a calcium salt.
Sgarbi, et al (6,286,323) teaches compositions for improving air conditioning
and
refrigeration systems containing a polar compound, dithiocarbamates, (3-olefin
(see claim 1)
and other ancillary components are set forth.
Robef-ts (6,110,877) teaches an extreme pressure lubricant composition
containing
amongst other ingredients bismuth compounds and a polyalphaolefin (e.g., l-
decene
homopolymer).
Rowah et al (4,889,647) sets forth molybdenum compounds useful in lubricants.
Objects of the Invention
A principal object of this invention is to produce an active, polarized
refrigerant oil
additive and extreme pressure Lubricant which will significantly improve heat
transfer in the
condenser and evaporator coils of a refrigeration system.
A further object of this invention is to produce a lubricant which efficiently
functions
as an extreme pressure lubricant in the compressor unit of refrigerators,
chillers, freezers, heat
pumps and air conditioners.
An important object of the invention is to provide an active, polarized
refrigerant oil
additive and extreme pressure lubricant that does not contain halogen or
sulfux as the
polarizing agent.
An additional object is to produce an extreme pressure lubricant which is
environmentally friendly.
A main object of this invention is to produce an extreme pressure lubricant
which will
efficiently lubricate the metal surfaces of a compressor system.
An important object of the invention is to provide an extreme pressure
lubricant for
refrigerants that does not contain halogen or sulfur as the polarizing agent.
A significant object of this invention is to produce a composition when
properly used
will decrease energy use, boost lubricity between metal to metal contact and
increase
efficiency.
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These and other objects of the present invention will become apparent from a
reading
of the following specification.
Identification and/or source of components of the inventive polarized
additive, metal
conditioner and extreme pressure lubricant are:
Combonent Identification
Polyalphaolefin Base Oil CAS: 88037-O1-4
Methyl Ester Base oil CAS: 68082-78-0
Fatty Acid Ester Base Oil CAS: 68424-31-7
Bismuth Carboxylate CAS: 34364-26-6
26896-20-8
Viscosity Improver Copolymer of Ethylene &
(ParatoneT"' 8232) Propylene (Olefins)
Antimony Dialkyldithiocarbamate VANLUBETM 73 (mixture)
Zinc Alkyldithiophosphate LUBRIZOLT"" 5178-F (mixture)
Organomolybdenum complex of MOLYVAN 855 (mixture)
Organic Amide
Dialkyldithiocarbamate Ester with OD-9413 (mixture)
Bismuth Carboxylate
Epoxidized Triglyceride Plas-Check 775TM
Acid Scavenger/Stabilizer
Olefin blend can be obtained as polyalphaolefin under the trade names Ethyl
Flo 166,
Durasyn 166 or Synfluid PA06 (Chevron-Phillips Co.).
Examples of operative bismuth carboxylates are bismuth neo-decanoate (CAS:
34364-
26-75), bismuth 2-ethylhexanoate and bismuth naphthenate or mixtures of these
bismuth
compounds and are available from OMG~' Cleveland, Ohio or R. T. VanderbiltTM
of Norwallc,
CT.
Polyalphaolefm is a hydrogenated synthetic hydrocarbon base fluid supplied by
the
EthylTM Corporation and has a CAS registry number of CAS: 68037-O1-4.
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AmocoTM supplies 1-decene, Homopolymer Hydrogenated and has a CAS No. 88037-
O1-4.
Examples of fatty acid base oils CAS: 68082-78-0, synonsym: methyl lardate,
available from Ferro Corporation, Hammond, Indiana.
Example of penterythritol esters of CS-Clo fatty acid are CAS: 68424-31-7.
Molybdenum compound can be obtained from R. T. VanderbiltT"~ under the
designation Molyvan 855.
Dialkyldithiocarbamate Ester with Bismuth Carboxylate can be obtained from R.
T.
VanderbiltT"" under the designation OD-9413.
Epoxidized triglyceride can be obtained from FerroT"' as Plas-Check 755TM.
Further examples of the active components used in the lubricant and metal
conditioner
of this invention are to be found in U. S. Patent 6,110,877 and bismuth
carboxylates are to be
found in U. S. Patent 5,576,273.
Exemplary of the refrigerant gas to which the lubricant metal conditioner is
to be
added are CFC, HCFC and HFC:C = carbon, F = fluorine, H = hydrogen). The
refrigerant
gases are conventional in the art, and specific examples are fluoropropane and
fluorobutane.
Additionally, this invention is compatible with refrigerants from the Freon
series and their
updated replacements, as well as the Methane series, the Ethane series, and
the Propane
series, Ammonia, Sulfur Dioxide and Carbon Dioxide gasses.
BRIEF SUMMARY OF THE INVENTION
In its broadest aspect the herein disclosed invention is directed to the
incorporation of
effective amounts of a bismuth compound into the refrigerant oil reservoir or
the refrigerant
gas of a cooling system such as chillers, coolers, refrigeration plants, air
conditioners,
refrigerators and heat pumps. Generally speaking, the bismuth compound would
be added
along with a lubricant to the refrigerant gas or oil. In preferred
embodiments, the bismuth
compound will be present at about 5 to I O percent of the lubricating or
refrigerant oil,
however, the optimum effective amounts could be determined by those skilled in
the art. It is
expected that the addition of a polarized lubricating oil and bismuth compound
to refrigerant
gas will boost metal-to-metal lubricity producing a decrease in energy
consumption and an
increase of over-all efficiency of the cooling equipment in which the
polarized bismuth
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compound which is non-toxic is employed. The bismuth containing lubricating
composition
is intended to prolong the life of compressors used in cooling equipment.
It is anticipated that dye tracers and/or bactericides may be added to the
bismuth
containing lubricant composition.
Broadly considered the herein disclosed non-halogenated metal conditioner and
extreme pressure lubricant additive useful in refrigerant gas comprises
effective amounts of:
a lubricant
bismuth carboxylate polarized extreme pressure additive,
an antimony dialkyldithiocarbarnate anti-wear additive,
a viscosity improver,
and a molybdenum compound anti-friction additive,
optionally, a dialkyldithiocarbamate ester with bismuth carboxylate,
and/or an acid scavenger/stabilizer together in the compressor gas of a
cooling
unit.
The lubricant may comprise:
a polyalphaolefin base oil,
a methyl ester base oil,
a fatty acid ester base oil.
The herein disclosed lubricant composition is directed to a non-halogenated
(no
chlorine, fluorine, bromine, iodine, or astatine) metal conditioner/extreme
pressure lubricant
additive system, for use in the conditioning or lubricating of metal surfaces.
This formulation
is unique in that it is free from chemical elements of the Halogen Group,
particularly chlorine
and fluorine, which are known to combine with hydrogen and form highly
undesired
(corrosive) hydrochloric acid and hydrofluoric acid respectively. Applications
of the
invention include but are not limited to use as a Polarized Refrigerant
Additive Oil (PROA)
in consumer, industrial, commercial, military, and federal sector
refrigeration and air
conditioning systems, chillers and heat pumps and compressors. Use of this
additive system
as a PROA provides (1) significantly improved heat transfer in the evaporator
and condensing
coils, and (2) increased lubricity of refrigerant oils, significantly
enhancing compressor
operation and efficiency. The additive system is blended into the refrigerant
oil reservoir or
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refrigerant flow as appropriate to the equipment design. When used as a
polarized refrigerant
oil and lubricant additive, the composition of this invention is carried with
the primary
lubricant and moves throughout the system. The polar nature of the formula
refers to the
covalent molecular bonding which takes place between the negatively charged
additive
molecules and the positive charge of the metal surfaces. As each molecule
attaches itself to
metal surfaces within the system, it conditions these surfaces, displacing
dirt, carbon deposits
(coking), and lubricating oil build-up, eventually forming a thin, one
molecule thick layer of
the additive system. This provides the optimal conditions for efficient
thermal conductivity
within the heat exchanger systems of refrigeration/air conditioning equipment.
Additionally,
as a polar (molecular bonding) extreme pressure lubricant, it provides greatly
enhanced
lubrication to moving parts of refrigeration equipment.
The lubrication system may include in combination, a polyalphaolefm base oil,
a
methyl ester base oil, a fatty acid ester base oil (individually or as a
mixture), a bismuth
carboxylate polarized extreme pressure additive, a viscosity improver, a
molybdenum anti-
friction additive, and optionally, an additional bismuth compound additive,
and/or an acid
scavenger/stabilizer. In an embodiment when in operation, the lubricant
additive system is
present in a minor quantity and the primary lubricating oil or refrigerant is
present in a major
quantity, based on weight. In a preferred embodiment, the bismuth caxboxylate
is selected
from the group of bismuth neodecanoate, bismuth 2-ethylhexanoate, bismuth
naphthenate and
mixtures thereof. The polyalphaolefm base oil is from about 20 to 40 percent
of said additive
system and preferably from about 28 to 3 8 percent of the additive system. The
methylester
base oil is from about 15 to 35 percent of the additive system and preferably
from about 24 to
33 percent of said system. The fatty acid ester base oil is from about 1 to 10
percent of said
additive system and preferably from about 2 to 5 percent of the additive
system. The bismuth
carboxylate is present in the range from about 20 to 40 percent, and
preferably from about 23
to 32 percent. About 1 to 8 percent of an olefin blend is employed in the
system as a
viscosity improver, preferably in the amount from about 3 to 5 percent of the
additive system
as a copolymer of ethylene and propylene. A molybdenum compound may be
introduced
from about 0.1 to 8 percent of the system. Optionally, an additional bismuth
compound may
be introduced from about 0.1 to 8 percent of the system. Optionally, about 1
to 3 percent of
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m epoxidized triglyceride may be employed in the system as an acid scavenger
and/or
stabilizer.
Note particularly that the lubricant composition does not contain chlorine or
sulfur
compounds which would adversely affect the components of the air conditioner,
refrigerator
or heat pump.
In a preferred embodiment of this invention, there is envisioned the following
composition for addition to the refrigerant of the compressor of, for example,
air conditioners,
refrigerators and heat pumps in approximately the following proportions:
Component Percent
Polyalphaolefin Base Oil 32.58
Methyl Ester Base oil 28.00
Fatty Acid Ester Base Oil 3.06
Bismuth Carboxylate 27.00
Viscosity Improver 4.00
(ParatoneTM 8232).
To this preferred embodiment, optional alternative ingredients can be added to
tailor
the product to a particular industry, application or customer. For example,
epoxidized
triglycerides 1-2 percent can be added. Another component contemplated for use
is an anti-
microbial biocide as, for example, ionic silver.
A special embodiment of this invention includes the addition of a tracer dye,
e.g.,
fluorescent tracer dye, to the lubricant which is to be supplied to the
refrigerant of the cooling
unit.
While the invention has been defined in terms of air conditioners,
refrigerators or heat
pumps, the invention is intended to cover like devices which involve
refrigerant gases.
An elegant embodiment of this invention involves a lubricating composition for
lubricating gear boxes as well as a lubricating composition for compressors.
Broadly
considered this elegant composition comprises effective amounts of bismuth
compound,
molybdenum compound and lubricating oil as for example:
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Component Percent
Lubricating oil 40 - 70
Bismuth compound 20 - 40
Molybdenum compound 1 - 20
In addition, a zinc compound can be added to this composition in the range of
.1 - 2
%. An antimony compound may be added in the range of 1 - 10%. The composition
may
also be added to a refrigerant gas and can also be accompanied by ~ tracer to
detect leaks.
Antimicrobial agents may be added as a preservative. In this Iatter respect,
silver containing
antimicrobial agents are preferred. A viscosity improver with an SAE iso-n
tunber of 32 - 68
would be an operative additive for the composition.
A specific preferred embodiment of the conditioner-lubricating composition
involves:
Component Percent
Bismuth compound 30
Molybdenum compound 6
Lubricating oil 64
Rowan et al (4,889,647) is exemplary of molybdenum compounds useful in the
herein
disclosed invention and is incorporated by reference to show the same.
The amounts of the ingredients set forth herein are exemplary and could be
varied
somewhat as readily understood by those skilled in the art. Effective amounts
of the
ingredients could also be determined by those skilled in the art.
In general, any type of lubricant or lubricating oil would be appropriate. The
terms
lubricant and lubricating oil may be used interchangeably.
Obviously, many modifications may be made without departing from the basic
spirit
of the present invention. Accordingly, it will be appreciated by those skilled
in the at-t that
within the scope of the appended claims, the invention may be practiced other
than has been
specifically described herein.
