U.S. patent application number 12/193282 was filed with the patent office on 2008-12-25 for heat transfer and refrigerant compositions comprising 3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene and a hydrocarbon.
This patent application is currently assigned to E.I. DU PONT DE NEMOURS AND COMPANY. Invention is credited to Barbara Haviland Minor, Mario Joseph Nappa, Velliyur Nott Mallikarjuna Rao.
Application Number | 20080315149 12/193282 |
Document ID | / |
Family ID | 36754513 |
Filed Date | 2008-12-25 |
United States Patent
Application |
20080315149 |
Kind Code |
A1 |
Nappa; Mario Joseph ; et
al. |
December 25, 2008 |
HEAT TRANSFER AND REFRIGERANT COMPOSITIONS COMPRISING
3,3,4,4,5,5,6,6,6-NONAFLUORO-1-HEXENE AND A HYDROCARBON
Abstract
The present invention relates to: Disclosed herein are
3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene compositions for use in
refrigeration and air conditioning systems, particularly in
centrifugal compressor systems. Also disclosed are
3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene in combination with
hydrocarbons, which are azeotropic or near azeotropic.
Inventors: |
Nappa; Mario Joseph;
(Newark, DE) ; Minor; Barbara Haviland; (Elkton,
MD) ; Rao; Velliyur Nott Mallikarjuna; (Wilmington,
DE) |
Correspondence
Address: |
E I DU PONT DE NEMOURS AND COMPANY;LEGAL PATENT RECORDS CENTER
BARLEY MILL PLAZA 25/1122B, 4417 LANCASTER PIKE
WILMINGTON
DE
19805
US
|
Assignee: |
E.I. DU PONT DE NEMOURS AND
COMPANY
WILMINGTON
DE
|
Family ID: |
36754513 |
Appl. No.: |
12/193282 |
Filed: |
August 18, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11410587 |
Apr 25, 2006 |
7449126 |
|
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12193282 |
|
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60674921 |
Apr 26, 2005 |
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Current U.S.
Class: |
252/67 ; 252/68;
510/177 |
Current CPC
Class: |
C11D 7/5072 20130101;
C09K 2205/12 20130101; C09K 5/045 20130101 |
Class at
Publication: |
252/67 ; 252/68;
510/177 |
International
Class: |
C09K 5/04 20060101
C09K005/04; C11D 7/50 20060101 C11D007/50 |
Claims
1. A refrigerant or heat transfer fluid composition comprising
3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene and at least one
hydrofluorocarbon selected from the group consisting of:
2,2-dimethylbutane; 2,3-dimethylbutane; 2-methylpentane;
cyclopentane; and methylcyclopentane.
2. A refrigerant or heat transfer fluid composition as in claim 1,
wherein the composition is selected from the group consisting of:
PFBE and 2,2-dimethylbutane; PFBE and 2,3-dimethylbutane; PFBE and
2-methylpentane; PFBE and cyclopentane; and PFBE and
methylcyclopentane.
3. A refrigerant or heat transfer fluid composition as in claim 1,
wherein the composition is an azeotropic or near-azeotropic
composition selected from the group consisting of: about 1 to about
99 weight percent of 3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene and
about 1 to about 99 weight percent of 2,2-dimethylbutane; about 1
to about 99 weight percent of 3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene
and about 1 to about 99 weight percent of 2,3-dimethylbutane; about
1 to about 99 weight percent of
3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene and about 1 to about 99
weight percent of 2-methylpentane; about 29 to about 85 weight
percent of 3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene and about 15 to
about 71 weight percent of cyclopentane; and about 49 to about 99
weight percent of 3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene and about 1
to about 51 weight percent of methylcyclopentane.
4. A refrigerant or heat transfer fluid composition as in claim 1,
wherein the composition is an azeotropic or near-azeotropic
composition selected from the group consisting of: about 40 to
about 99 weight percent of 3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene
and about 1 to about 60 weight percent of 2,2-dimethylbutane; about
40 to about 99 weight percent of
3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene and about 1 to about 60
weight percent of 2,3-dimethylbutane; about 40 to about 99 weight
percent of 3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene and about 1 to
about 60 weight percent of 2-methylpentane; about 40 to about 85
weight percent of 3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene and about
15 to about 60 weight percent of cyclopentane; and about 60 to
about 99 weight percent of 3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene
and about 1 to about 40 weight percent of methylcyclopentane.
5. A refrigerant or heat transfer fluid composition as in claim 1,
wherein the composition is an azeotropic composition selected from
the group consisting of: 61.7 weight percent of
3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene and 38.3 weight percent of
2,3-dimethylbutane having a vapor pressure of about 14.7 psia (101
kPa) at a temperature of about 57.2.degree. C.; 79.1 weight percent
of 3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene and 20.9 weight percent of
2-methylpentane having a vapor pressure of about 14.7 psia (101
kPa) at a temperature of about 58.1.degree. C.; 61.9 weight percent
of 3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene and 38.1 weight percent of
cyclopentane having a vapor pressure of about 14.7 psia (101 kPa)
at a temperature of about 42.5.degree. C.; and 88.3 weight percent
of 3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene and 11.7 weight percent of
methylcyclopentane having a vapor pressure of about 14.7 psia (101
kPa) at a temperature of about 57.6.degree. C.
6. A method for producing refrigeration, said method comprising
evaporating the refrigerant or heat transfer composition of claim 1
in the vicinity of a body to be cooled, and thereafter condensing
said composition.
7. A method for producing heat, said method comprising condensing
the refrigerant or heat transfer composition of claim 1 in the
vicinity of a body to be heated, and thereafter evaporating said
composition.
8. A method for transferring heat, said method comprising
transferring the compositions of claim 1 from a heat source to a
heat sink.
9. A composition as in claim 1 further comprising at least one
ultra-violet fluorescent dye selected from the group consisting of
naphthalimides, perylenes, coumarins, anthracenes, phenanthracenes,
xanthenes, thioxanthenes, naphthoxanthenes, fluoresceins,
derivatives of said dye and combinations thereof.
10. A composition as in claim 9, further comprising at least one
solubilizing agent selected from the group consisting of
hydrocarbons, dimethylether, polyoxyalkylene glycol ethers, amides,
ketones, nitriles, chlorocarbons, esters, lactones, aryl ethers,
hydrofluoroethers, and 1,1,1-trifluoroalkanes; and wherein the
refrigerant and solubilizing agent are not the same compound.
11. A composition as in claim 10, wherein said solubilizing agent
is selected from the group consisting of: a) polyoxyalkylene glycol
ethers represented by the formula
R.sup.1[(OR.sup.2).sub.xOR.sup.3].sub.y, wherein: x is an integer
from 1 to 3; y is an integer from 1 to 4; R.sup.1 is selected from
hydrogen and aliphatic hydrocarbon radicals having 1 to 6 carbon
atoms and y bonding sites; R.sup.2 is selected from aliphatic
hydrocarbylene radicals having from 2 to 4 carbon atoms; R.sup.3 is
selected from hydrogen, and aliphatic and alicyclic hydrocarbon
radicals having from 1 to 6 carbon atoms; at least one of R.sup.1
and R.sup.3 is selected from said hydrocarbon radicals; and wherein
said polyoxyalkylene glycol ethers have a molecular weight of from
about 100 to about 300 atomic mass units; b) amides represented by
the formulae R.sup.1C(O)NR.sup.2R.sup.3 and
cyclo-[R.sup.4CON(R.sup.5)--], wherein R.sup.1, R.sup.2, R.sup.3
and R.sup.5 are independently selected from aliphatic and alicyclic
hydrocarbon radicals having from 1 to 12 carbon atoms, and at most
one aromatic radical having from 6 to 12 carbon atoms; R.sup.4 is
selected from aliphatic hydrocarbylene radicals having from 3 to 12
carbon atoms; and wherein said amides have a molecular weight of
from about 100 to about 300 atomic mass units; c) ketones
represented by the formula R.sup.1C(O)R.sup.2, wherein R.sup.1 and
R.sup.2 are independently selected from aliphatic, alicyclic and
aryl hydrocarbon radicals having from 1 to 12 carbon atoms, and
wherein said ketones have a molecular weight of from about 70 to
about 300 atomic mass units; d) nitriles represented by the formula
R.sup.1CN, wherein R.sup.1 is selected from aliphatic, alicyclic or
aryl hydrocarbon radicals having from 5 to 12 carbon atoms, and
wherein said nitriles have a molecular weight of from about 90 to
about 200 atomic mass units; e) chlorocarbons represented by the
formula RCl.sub.x, wherein; x is 1 or 2; R is selected from
aliphatic and alicyclic hydrocarbon radicals having from 1 to 12
carbon atoms; and wherein said chlorocarbons have a molecular
weight of from about 100 to about 200 atomic mass units; f) aryl
ethers represented by the formula R.sup.1OR.sup.2, wherein: R.sup.1
is selected from aryl hydrocarbon radicals having from 6 to 12
carbon atoms; R.sup.2 is selected from aliphatic hydrocarbon
radicals having from 1 to 4 carbon atoms; and wherein said aryl
ethers have a molecular weight of from about 100 to about 150
atomic mass units; g) 1,1,1-trifluoroalkanes represented by the
formula CF.sub.3R.sup.1, wherein R.sup.1 is selected from aliphatic
and alicyclic hydrocarbon radicals having from about 5 to about 15
carbon atoms; h) fluoroethers represented by the formula
R.sup.1OCF.sub.2CF.sub.2H, wherein R.sup.1 is selected from
aliphatic, alicyclic and aromatic hydrocarbon radicals having from
about 5 to about 15 carbon atoms; or wherein said fluoroethers are
derived from fluoro-olefins and polyols, wherein said
fluoro-olefins are of the type CF.sub.2.dbd.CXY, wherein X is
hydrogen, chlorine or fluorine, and Y is chlorine, fluorine,
CF.sub.3 or OR.sub.f, wherein R.sub.f is CF.sub.3, C.sub.2F.sub.5,
or C.sub.3F.sub.7; and said polyols are linear or branched, wherein
said linear polyols are of the type HOCH.sub.2
(CHOH).sub.x(CRR').sub.yCH.sub.2OH, wherein R and R' are hydrogen,
CH.sub.3 or C.sub.2H.sub.5, x is an integer from 0-4, y is an
integer from 0-3 and z is either zero or 1, and said branched
polyols are of the type
C(OH).sub.t(R).sub.u(CH.sub.2OH).sub.v[(CH2).sub.mCH2OH].sub.w,
wherein R may be hydrogen, CH.sub.3 or C.sub.2H.sub.5, m is an
integer from 0 to 3, t and u are 0 or 1, v and w are integers from
0 to 4, and also wherein t+u+v+w=4; i) lactones represented by
structures [B], [C], and [D]: ##STR00036## wherein, R.sub.1 through
R.sub.8 are independently selected from hydrogen, linear, branched,
cyclic, bicyclic, saturated and unsaturated hydrocarbyl radicals;
and the molecular weight is from about 100 to about 300 atomic mass
units; and j) esters represented by the general formula
R.sup.1CO.sub.2R.sup.2, wherein R.sup.1 and R.sup.2 are
independently selected from linear and cyclic, saturated and
unsaturated, alkyl and aryl radicals; and wherein said esters have
a molecular weight of from about 80 to about 550 atomic mass
units.
12. A method for detecting the composition of claim 9 in a
compression refrigeration or air conditioning apparatus, said
method comprising providing said composition to said apparatus, and
providing a suitable means for detecting said composition at a leak
point or in the vicinity of said apparatus.
13. A method of producing refrigeration as in claim 6, wherein the
refrigerant or heat transfer composition further comprises at least
one ultra-violet fluorescent dye selected from the group consisting
of naphthalimides, perylenes, coumarins, anthracenes,
phenanthracenes, xanthenes, thioxanthenes, naphthoxanthenes,
fluoresceins, derivatives of said dye and combinations thereof.
14. A method of producing heat as in claim 7, wherein the
refrigerant or heat transfer composition further comprises at least
one ultra-violet fluorescent dye selected from the group consisting
of naphthalimides, perylenes, coumarins, anthracenes,
phenanthracenes, xanthenes, thioxanthenes, naphthoxanthenes,
fluoresceins, derivatives of said dye and combinations thereof.
15. A composition as in claim 1 further comprising a stabilizer,
water scavenger, or odor masking agent.
16. A composition as in claim 15 wherein said stabilizer is
selected from the group consisting of nitromethane, hindered
phenols, hydroxylamines, thiols, phosphites and lactones.
17. A method as in claim 6, wherein said method comprises producing
refrigeration in a refrigeration or air conditioning apparatus
employing a multi-stage centrifugal compressor.
18. The method of claim 17 wherein said multi-stage centrifugal
compressor is a two-stage centrifugal compressor.
19. A method as in claim 7, wherein said method comprises producing
heat in a refrigeration apparatus employing a multi-stage
centrifugal compressor.
20. A method as in claim 19 wherein said multi-stage centrifugal
compressor is a two-stage centrifugal compressor.
21. The composition of claim 15 wherein said water scavenger is an
ortho ester.
22. A method as in claim 6, wherein said method comprises producing
refrigeration in a refrigeration or air conditioning apparatus
employing a mini-centrifugal compressor powered by an engine
exhaust gas driven turbine.
23. A method as in claim 6, wherein said method comprises producing
refrigeration in a refrigeration or air conditioning apparatus
employing a mini-centrifugal compressor powered by a ratioed gear
drive assembly with a ratioed belt drive.
24. A process for removing residue from a surface comprising: (a)
contacting the surface with an azeotropic or azeotrope-like
composition comprising perfluorobutylethylene
(3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene (PFBE)) and at least one
hydrofluorocarbon is selected from the group consisting of:
2,2-dimethylbutane; 2,3-dimethylbutane; 2-methylpentane;
cyclopentane; and methylcyclopentane; (b) recovering the surface
from the composition.
25. A process as in claim 24 wherein said residue comprises an
oil.
26. A process as in claim 24 wherein said residue comprises a rosin
flux.
27. A process as in claim 24 wherein the surface is an integrated
circuit device.
Description
CROSS REFERENCE(S) TO RELATED APPLICATION(S)
[0001] This application is a divisional of U.S. application Ser.
No. 11/410,587, filed Apr. 25, 2006, which claims priority benefit
of U.S. Provisional application 60/674,921, filed Apr. 26,
2005.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to compositions for use in
heat transfer, refrigeration and air-conditioning systems
comprising 3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene (PFBE) and at
least one hydrocarbon including refrigeration and air-conditioning
systems employing a centrifugal compressor. The compositions of the
present invention may be azeotropic or near azeotropic. These
compositions are also useful in cleaning applications as a
defluxing agent and for removing oils or residues from a
surface.
[0004] 2. Description of Related Art
[0005] The refrigeration industry has been working for the past few
decades to find replacement refrigerants for the ozone depleting
chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs)
being phased out as a result of the Montreal Protocol. The solution
for most refrigerant producers has been the commercialization of
hydrofluorocarbon (HFC) refrigerants. The new HFC refrigerants,
HFC-134a being the most widely used at this time, have zero ozone
depletion potential and thus are not affected by the current
regulatory phase-out as a result of the Montreal Protocol.
[0006] Further, environmental regulations may ultimately cause
global phase-out of certain HFC refrigerants. Currently, the
automobile industry is facing regulations relating to global
warming potential (GWP) for refrigerants used in mobile
air-conditioning. Therefore, there is a great current need to
identify new refrigerants with reduced GWP for the automobile
air-conditioning market. Should the regulations be more broadly
applied in the future, an even greater need will be felt for low
GWP refrigerants that can be used in all areas of the refrigeration
and air-conditioning industry.
[0007] Currently proposed replacement refrigerants for HFC-134a
include HFC-152a, pure hydrocarbons such as butane or propane, or
"natural" refrigerants such as CO.sub.2 or ammonia. Many of these
suggested replacements are toxic, flammable, and/or have low energy
efficiency. Therefore, new alternatives are constantly being
sought.
The present invention provides refrigerant compositions and heat
transfer fluids having unique characteristics to meet the demands
of low or zero ozone depletion potential, and lower GWP.
[0008] The present invention also provides azeotropic and
azeotrope-like compositions useful in semiconductor chip and
circuit board cleaning, defluxing, and degreasing processes. The
present compositions are non-flammable, and as they do not
fractionate during use, they will not produce flammable
compositions during use. Additionally, the used azeotropic solvent
mixtures may be re-distilled and re-used without composition.
BRIEF SUMMARY OF THE INVENTION
[0009] In one embodiment, the present invention relates to
refrigerant or heat transfer fluid compositions comprising
3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene (PFBE) and at least one
hydrocarbon compound selected from the group consisting of: [0010]
2,2-dimethylbutane; [0011] 2,3-dimethylbutane; [0012]
2-methylpentane; [0013] 3-methylpentane; [0014] cyclopentane; and
[0015] methylcyclopentane.
[0016] In another embodiment, the present invention relates to the
above listed compositions specifically for use in refrigeration or
air-conditioning systems employing a centrifugal compressor.
[0017] In yet another embodiment, the present invention relates to
the above listed compositions specifically for use in refrigeration
or air-conditioning systems employing a two-stage centrifugal
compressor.
[0018] In yet another embodiment, the present invention relates to
the above listed compositions specifically for use in refrigeration
or air-conditioning systems employing a single pass/single slab
heat exchanger.
[0019] In yet another embodiment, the present invention relates to
azeotropic or near azeotropic compositions that are useful in heat
transfer, refrigeration or air-conditioning systems. The
compositions are also useful in refrigeration or air-conditioning
systems employing a centrifugal compressor.
[0020] In yet another embodiment, the present invention relates to
refrigerant or heat transfer fluid compositions containing
ultra-violet fluorescent dye for leak detection.
[0021] In yet another embodiment, the present invention relates to
processes for producing refrigeration, heat, and transfer of heat
from a heat source to a heat sink using the present inventive
compositions. In yet another embodiment, the present invention
relates to processes for cleaning surfaces and for removing residue
from surfaces, such as integrated circuit devices.
DETAILED DESCRIPTION OF THE INVENTION
[0022] In this specification, when an amount, concentration, or
other value or parameter is given as either a range, preferred
range, or a list of upper preferable values and lower preferable
values, this is to be understood as specifically disclosing all
ranges formed from any pair of any upper range limit or preferred
value and any lower range limit or preferred value, regardless of
whether ranges are separately disclosed. Where a range of numerical
values is recited herein, unless otherwise stated, the range is
intended to include the endpoints thereof, and all integers and
fractions within the range. It is not intended that the scope of
the invention be limited to the specific values recited when
defining a range.
[0023] The refrigerant or heat transfer fluid compositions of the
present invention comprise 3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene
(PFBE) and at least one hydrocarbon compound.
[0024] PFBE is a hydrofluorocarbon compound with CAS registry
number [19430-93-4]. It is commercially available from DuPont.
[0025] The hydrocarbons of the present invention comprise compounds
containing hydrogen and carbon. Such hydrocarbons may be straight
chain, branched chain or cyclic compounds and have from about 5 to
10 carbon atoms. Preferred hydrocarbons have from 5 to 7 carbon
atoms. Representative hydrocarbons of the present invention are
listed in Table 1.
TABLE-US-00001 TABLE 1 CAS Reg. Compound Chemical Formula No.
Hydrocarbons 2,2-dimethylbutane CH.sub.3CH.sub.2C(CH.sub.3).sub.3
75-83-2 2,3-dimethylbutane CH.sub.3CH(CH.sub.3)CH(CH.sub.3)CH.sub.3
79-29-8 2-methylpentane
CH.sub.3CH(CH.sub.3)CH.sub.2CH.sub.2CH.sub.3 107-83-5
3-methylpentane CH.sub.3CH.sub.2CH(CH.sub.3) CH.sub.2CH.sub.3
96-14-0 cyclopentane cyclo- 287-92-3
CH.sub.2CH.sub.2CH.sub.2CH.sub.2CH.sub.2CH.sub.2--
methylcyclopentane cyclo- 96-37-7
CH.sub.2CH(CH.sub.3)CH.sub.2CH.sub.2CH.sub.2--
[0026] The compounds listed in Table 1 are readily made by those
skilled in the art and are available from many chemical supply
houses.
[0027] The compositions of the present invention may be prepared by
any convenient method to combine the desired amounts of the
individual components. A preferred method is to weigh the desired
component amounts and thereafter combine the components in an
appropriate vessel. Agitation may be used, if desired.
[0028] The refrigerant or heat transfer fluid compositions of the
present invention include PFBE with at least one compound selected
from the group consisting of: [0029] 2,2-dimethylbutane; [0030]
2,3-dimethylbutane; [0031] 2-methylpentane; [0032] 3-methylpentane;
[0033] cyclopentane; and [0034] methylcyclopentane. The refrigerant
or heat transfer fluid compositions of the present invention may be
azeotropic or near azeotropic compositions. By azeotropic
composition is meant a constant-boiling mixture of two or more
substances that behaves as a single substance. One way to
characterize an azeotropic composition is that the vapor produced
by partial evaporation or distillation of the liquid has the same
composition as the liquid from which it is evaporated or distilled,
i.e., the mixture distills/refluxes without compositional change.
Constant-boiling compositions are characterized as azeotropic
because they exhibit either a maximum or minimum boiling point, as
compared with that of the non-azeotropic mixture of the same
components. An azeotropic composition will not fractionate within
the refrigeration or air-conditioning system during operation, thus
maintaining the efficiency of the system. Additionally, an
azeotropic composition will not fractionate upon leakage from the
refrigeration or air-conditioning system. In the situation where
one component of a mixture is flammable, fractionation during
leakage could lead to a flammable composition either within the
system or outside of the system.
[0035] A "near azeotropic composition", also sometimes called an
"azeotropic-like composition" is a substantially constant boiling
liquid admixture of two or more substances that behaves essentially
as a single substance. One way to characterize a near azeotropic
composition is that the vapor produced by partial evaporation or
distillation of the liquid has substantially the same composition
as the liquid from which it was evaporated or distilled, that is,
the admixture distills/refluxes without substantial composition
change. Another way to characterize a near azeotropic composition
is that the bubble point vapor pressure and the dew point vapor
pressure of the composition at a particular temperature are
substantially the same. Herein, a composition is near azeotropic
if, after 50 weight percent of the composition is removed, such as
by evaporation or boiling off, the difference in vapor pressure
between the original composition and the composition remaining
after 50 weight percent of the original composition has been
removed is less than about 10 percent.
[0036] The azeotropic PFBE refrigerant or heat transfer fluid
compositions of the present invention are listed in Table 2.
TABLE-US-00002 TABLE 2 Azeotrope Point Azeotrope Composition
Boiling wt % wt % Point Component A Component B (A) (B) (.degree.
C.) PFBE 2,3-dimethylbutane 61.7 38.3 57.2 PFBE 2-methylpentane
79.1 20.9 58.1 PFBE 3-methylpentane 90.0 10.0 58.7 PFBE
cyclopentane 61.9 38.1 42.5 PFBE methylcyclopentane 88.3 11.7
57.6
[0037] The near azeotropic refrigerant and heat transfer fluid
compositions and concentration ranges of the present invention are
listed in Table 3.
TABLE-US-00003 TABLE 3 PFBE plus B: Near Azeotropic Ranges
Hydrocarbons wt % PFBE/wt % B 2,2-dimethylbutane 1-99/1-99
2,3-dimethylbutane 1-99/1-99 2-methylpentane 1-99/1-99
3-methylpentane 1-99/1-99 cyclopentane 29-85/15-71
methylcyclopentane 49-99/1-51
In another embodiment of the invention, near azeotropic refrigerant
and heat transfer compositions and concentration ranges of the
present invention which have reduced flammability are listed in
Table 4.
TABLE-US-00004 TABLE 4 PFBE plus B: Near Azeotropic Ranges
Hydrocarbons wt % PFBE/wt % B 2,2-dimethylbutane 40-99/1-60
2,3-dimethylbutane 40-99/1-60 2-methylpentane 40-99/1-60
3-methylpentane 40-99/1-60 cyclopentane 40-85/15-60
methylcyclopentane 60-99/1-40
[0038] The compositions of the present invention may further
comprise about 0.01 weight percent to about 5 weight percent of a
stabilizer, free radical scavenger or antioxidant. Such additives
include but are not limited to, nitromethane, hindered phenols,
hydroxylamines, thiols, phosphites, or lactones. Single additives
or combinations may be used.
[0039] The compositions of the present invention may further
comprise about 0.01 weight percent to about 5 weight percent of a
water scavenger (drying compound). Such water scavengers may
comprise ortho esters such as trimethyl-, triethyl-, or
tripropylorthoformate.
[0040] The compositions of the present invention may further
comprise an ultra-violet (UV) dye and optionally a solubilizing
agent. The UV dye is a useful component for detecting leaks of the
refrigerant and heat transfer fluid compositions by permitting one
to observe the fluorescence of the dye in the refrigerant or heat
transfer fluid compositions at a leak point or in the vicinity of
refrigeration or air-conditioning apparatus. One may observe the
fluorescence of the dye under an ultra-violet light. Solubilizing
agents may be needed to increase solubility of such UV dyes in some
refrigerants and heat transfer fluids.
By "ultra-violet" dye is meant a UV fluorescent composition that
absorbs light in the ultra-violet or "near" ultra-violet region of
the electromagnetic spectrum. The fluorescence produced by the UV
fluorescent dye under illumination by a UV light that emits
radiation with wavelength anywhere from 10 nanometer to 750
nanometer may be detected. Therefore, if refrigerant or heat
transfer fluid containing such a UV fluorescent dye is leaking from
a given point in a refrigeration or air-conditioning apparatus, the
fluorescence can be detected at the leak point. Such UV fluorescent
dyes include but are not limited to naphthalimides, perylenes,
coumarins, anthracenes, phenanthracenes, xanthenes, thioxanthenes,
naphthoxanthenes, fluoresceins, and derivatives or combinations
thereof. Solubilizing agents of the present invention comprise at
least one compound selected from the group consisting of
hydrocarbons, hydrocarbon ethers, polyoxyalkylene glycol ethers,
amides, nitriles, ketones, chlorocarbons, esters, lactones, aryl
ethers, fluoroethers and 1,1,1-trifluoroalkanes.
[0041] Hydrocarbon solubilizing agents of the present invention
comprise hydrocarbons including straight chained, branched chain or
cyclic alkanes or alkenes containing 16 or fewer carbon atoms and
only hydrogen with no other functional groups. Representative
hydrocarbon solubilizing agents comprise propane, propylene,
cyclopropane, n-butane, isobutane, n-pentane, octane, decane, and
hexadecane. It should be noted that if the refrigerant is a
hydrocarbon, then the solubilizing agent may not be the same
hydrocarbon.
[0042] Hydrocarbon ether solubilizing agents of the present
invention comprise ethers containing only carbon, hydrogen and
oxygen, such as dimethyl ether (DME).
[0043] Polyoxyalkylene glycol ether solubilizing agents of the
present invention are represented by the formula
R.sup.1[(OR.sup.2).sub.xOR.sup.3].sub.y, wherein x is an integer
from 1-3; y is an integer from 1-4; R.sup.1 is selected from
hydrogen and aliphatic hydrocarbon radicals having 1 to 6 carbon
atoms and y bonding sites; R.sup.2 is selected from aliphatic
hydrocarbylene radicals having from 2 to 4 carbon atoms; R.sup.3 is
selected from hydrogen, and aliphatic and alicyclic hydrocarbon
radicals having from 1 to 6 carbon atoms; at least one of R.sup.1
and R.sup.3 is selected from said hydrocarbon radical; and wherein
said polyoxyalkylene glycol ethers have a molecular weight of from
about 100 to about 300 atomic mass units. As used herein, bonding
sites mean radical sites available to form covalent bonds with
other radicals. Hydrocarbylene radicals mean divalent hydrocarbon
radicals.
[0044] In the present invention, preferable polyoxyalkylene glycol
ether solubilizing agents are represented by
R.sup.1[(OR.sup.2).sub.xOR.sup.3].sub.y wherein x is preferably
1-2; y is preferably 1; R.sup.1 and R.sup.3 are preferably
independently selected from hydrogen and aliphatic hydrocarbon
radicals having 1 to 4 carbon atoms; R.sup.2 is preferably selected
from aliphatic hydrocarbylene radicals having from 2 or 3 carbon
atoms, most preferably 3 carbon atoms; the polyoxyalkylene glycol
ether molecular weight is preferably from about 100 to about 250
atomic mass units, most preferably from about 125 to about 250
atomic mass units. The R.sup.1 and R.sup.3 hydrocarbon radicals
having 1 to 6 carbon atoms may be linear, branched or cyclic.
Representative R.sup.1 and R.sup.3 hydrocarbon radicals include
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
tert-butyl, pentyl, isopentyl, neopentyl, tert-pentyl, cyclopentyl,
and cyclohexyl. Where free hydroxyl radicals on the present
polyoxyalkylene glycol ether solubilizing agents may be
incompatible with certain compression refrigeration apparatus
materials of construction (e.g. Mylar.RTM.), R.sup.1 and R.sup.3
are preferably aliphatic hydrocarbon radicals having 1 to 4 carbon
atoms, most preferably 1 carbon atom. The R.sup.2 aliphatic
hydrocarbylene radicals having from 2 to 4 carbon atoms form
repeating oxyalkylene radicals--(OR.sup.2).sub.x--that include
oxyethylene radicals, oxypropylene radicals, and oxybutylene
radicals. The oxyalkylene radical comprising R.sup.2 in one
polyoxyalkylene glycol ether solubilizing agent molecule may be the
same, or one molecule may contain different R.sup.2 oxyalkylene
groups. The present polyoxyalkylene glycol ether solubilizing
agents preferably comprise at least one oxypropylene radical. Where
R.sup.1 is an aliphatic or alicyclic hydrocarbon radical having 1
to 6 carbon atoms and y bonding sites, the radical may be linear,
branched or cyclic. Representative R.sup.1 aliphatic hydrocarbon
radicals having two bonding sites include, for example, an ethylene
radical, a propylene radical, a butylene radical, a pentylene
radical, a hexylene radical, a cyclopentylene radical and a
cyclohexylene radical. Representative R.sup.1 aliphatic hydrocarbon
radicals having three or four bonding sites include residues
derived from polyalcohols, such as trimethylolpropane, glycerin,
pentaerythritol, 1,2,3-trihydroxycyclohexane and
1,3,5-trihydroxycyclohexane, by removing their hydroxyl
radicals.
[0045] Representative polyoxyalkylene glycol ether solubilizing
agents include but are not limited to:
CH.sub.3OCH.sub.2CH(CH.sub.3)O(H or CH.sub.3) (propylene glycol
methyl (or dimethyl)ether),
CH.sub.3O[CH.sub.2CH(CH.sub.3)O].sub.2(H or CH.sub.3) (dipropylene
glycol methyl (or dimethyl)ether),
CH.sub.3O[CH.sub.2CH(CH.sub.3)O].sub.3(H or CH.sub.3) (tripropylene
glycol methyl (or dimethyl)ether),
C.sub.2H.sub.5OCH.sub.2CH(CH.sub.3)O(H or C.sub.2H.sub.5)
(propylene glycol ethyl (or diethyl)ether),
C.sub.2H.sub.5O[CH.sub.2CH(CH.sub.3)O].sub.2(H or C.sub.2H.sub.5)
(dipropylene glycol ethyl (or diethyl)ether),
C.sub.2H.sub.5O[CH.sub.2CH(CH.sub.3)O].sub.3(H or C.sub.2H.sub.5)
(tripropylene glycol ethyl (or diethyl)ether),
C.sub.3H.sub.7OCH.sub.2CH(CH.sub.3)O(H or C.sub.3H.sub.7)
(propylene glycol n-propyl (or di-n-propyl)ether),
C.sub.3H.sub.7O[CH.sub.2CH(CH.sub.3)O].sub.2(H or C.sub.3H.sub.7)
(dipropylene glycol n-propyl (or di-n-propyl)ether),
C.sub.3H.sub.7O[CH.sub.2CH(CH.sub.3)O].sub.3(H or C.sub.3H.sub.7)
(tripropylene glycol n-propyl (or di-n-propyl)ether),
C.sub.4H.sub.9OCH.sub.2CH(CH.sub.3)OH (propylene glycol n-butyl
ether), C.sub.4H.sub.9O[CH.sub.2CH(CH.sub.3)O].sub.2(H or
C.sub.4H.sub.9) (dipropylene glycol n-butyl (or di-n-butyl)ether),
C.sub.4H.sub.9O[CH.sub.2CH(CH.sub.3)O].sub.3(H or C.sub.4H.sub.9)
(tripropylene glycol n-butyl (or di-n-butyl)ether),
(CH.sub.3).sub.3COCH.sub.2CH(CH.sub.3)OH (propylene glycol t-butyl
ether), (CH.sub.3).sub.3CO[CH.sub.2CH(CH.sub.3)O].sub.2(H or
(CH.sub.3).sub.3) (dipropylene glycol t-butyl (or
di-t-butyl)ether),
(CH.sub.3).sub.3CO[CH.sub.2CH(CH.sub.3)O].sub.3(H or
(CH.sub.3).sub.3) (tripropylene glycol t-butyl (or
di-t-butyl)ether), C.sub.5H.sub.11OCH.sub.2CH(CH.sub.3)OH
(propylene glycol n-pentyl ether),
C.sub.4H.sub.9OCH.sub.2CH(C.sub.2H.sub.5)OH (butylene glycol
n-butyl ether), C.sub.4H.sub.9O[CH.sub.2CH(C.sub.2H.sub.5)O].sub.2H
(dibutylene glycol n-butyl ether), trimethylolpropane tri-n-butyl
ether (C.sub.2H.sub.5C(CH.sub.2O(CH.sub.2).sub.3CH.sub.3).sub.3)
and trimethylolpropane di-n-butyl ether
(C.sub.2H.sub.5C(CH.sub.2OC(CH.sub.2).sub.3CH.sub.3).sub.2CH.sub.2OH).
[0046] Amide solubilizing agents of the present invention comprise
those represented by the formulae R.sup.1C(O)NR.sup.2R.sup.3 and
cyclo-[R.sup.4C(O)N(R.sup.5)--], wherein R.sup.1, R.sup.2, R.sup.3
and R.sup.5 are independently selected from aliphatic and alicyclic
hydrocarbon radicals having from 1 to 12 carbon atoms; R.sup.4 is
selected from aliphatic hydrocarbylene radicals having from 3 to 12
carbon atoms; and wherein said amides have a molecular weight of
from about 100 to about 300 atomic mass units. The molecular weight
of said amides is preferably from about 160 to about 250 atomic
mass units. R.sup.1, R.sup.2, R.sup.3 and R.sup.5 may optionally
include substituted hydrocarbon radicals, that is, radicals
containing non-hydrocarbon substituents selected from halogens
(e.g., fluorine, chlorine) and alkoxides (e.g. methoxy). R.sup.1,
R.sup.2, R.sup.3 and R.sup.5 may optionally include
heteroatom-substituted hydrocarbon radicals, that is, radicals,
which contain the atoms nitrogen (aza-), oxygen (oxa-) or sulfur
(thia-) in a radical chain otherwise composed of carbon atoms. In
general, no more than three non-hydrocarbon substituents and
heteroatoms, and preferably no more than one, will be present for
each 10 carbon atoms in R.sup.1-3, and the presence of any such
non-hydrocarbon substituents and heteroatoms must be considered in
applying the aforementioned molecular weight limitations. Preferred
amide solubilizing agents consist of carbon, hydrogen, nitrogen and
oxygen. Representative R.sup.1, R.sup.2, R.sup.3 and R.sup.5
aliphatic and alicyclic hydrocarbon radicals include methyl, ethyl,
propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl,
isopentyl, neopentyl, tert-pentyl, cyclopentyl, cyclohexyl, heptyl,
octyl, nonyl, decyl, undecyl, dodecyl and their configurational
isomers. A preferred embodiment of amide solubilizing agents are
those wherein R.sup.4 in the aforementioned formula
cyclo-[R.sup.4C(O)N(R.sup.5)--] may be represented by the
hydrocarbylene radical (CR.sup.6R.sup.7).sub.n, in other words, the
formula cyclo-[(CR.sup.6R.sup.7).sub.nC(O)N(R.sup.5)--] wherein the
previously-stated values for molecular weight apply; n is an
integer from 3 to 5; R.sup.5 is a saturated hydrocarbon radical
containing 1 to 12 carbon atoms; R.sup.6 and R.sup.7 are
independently selected (for each n) by the rules previously offered
defining R.sup.1-3. In the lactams represented by the formula:
cyclo-[(CR.sup.6R.sup.7).sub.nC(O)N(R.sup.5)--], all R.sup.6 and
R.sup.7 are preferably hydrogen, or contain a single saturated
hydrocarbon radical among the n methylene units, and R.sup.5 is a
saturated hydrocarbon radical containing 3 to 12 carbon atoms. For
example, 1-(saturated hydrocarbon
radical)-5-methylpyrrolidin-2-ones.
[0047] Representative amide solubilizing agents include but are not
limited to: 1-octylpyrrolidin-2-one, 1-decylpyrrolidin-2-one,
1-octyl-5-methylpyrrolidin-2-one, 1-butylcaprolactam,
1-cyclohexylpyrrolidin-2-one, 1-butyl-5-methylpiperid-2-one,
1-pentyl-5-methylpiperid-2-one, 1-hexylcaprolactam,
1-hexyl-5-methylpyrrolidin-2-one, 5-methyl-1-pentylpiperid-2-one,
1,3-dimethylpiperid-2-one, 1-methylcaprolactam,
1-butyl-pyrrolidin-2-one, 1,5-dimethylpiperid-2-one,
1-decyl-5-methylpyrrolidin-2-one, 1-dodecylpyrrolid-2-one,
N,N-dibutylformamide and N,N-diisopropylacetamide.
[0048] Ketone solubilizing agents of the present invention comprise
ketones represented by the formula R.sup.1C(O)R.sup.2, wherein
R.sup.1 and R.sup.2 are independently selected from aliphatic,
alicyclic and aryl hydrocarbon radicals having from 1 to 12 carbon
atoms, and wherein said ketones have a molecular weight of from
about 70 to about 300 atomic mass units. R.sup.1 and R.sup.2 in
said ketones are preferably independently selected from aliphatic
and alicyclic hydrocarbon radicals having 1 to 9 carbon atoms. The
molecular weight of said ketones is preferably from about 100 to
200 atomic mass units. R.sup.1 and R.sup.2 may together form a
hydrocarbylene radical connected and forming a five, six, or
seven-membered ring cyclic ketone, for example, cyclopentanone,
cyclohexanone, and cycloheptanone. R.sup.1 and R.sup.2 may
optionally include substituted hydrocarbon radicals, that is,
radicals containing non-hydrocarbon substituents selected from
halogens (e.g., fluorine, chlorine) and alkoxides (e.g. methoxy).
R.sup.1 and R.sup.2 may optionally include heteroatom-substituted
hydrocarbon radicals, that is, radicals, which contain the atoms
nitrogen (aza-), oxygen (keto-, oxa-) or sulfur (thia-) in a
radical chain otherwise composed of carbon atoms. In general, no
more than three non-hydrocarbon substituents and heteroatoms, and
preferably no more than one, will be present for each 10 carbon
atoms in R.sup.1 and R.sup.2, and the presence of any such
non-hydrocarbon substituents and heteroatoms must be considered in
applying the aforementioned molecular weight limitations.
Representative R.sup.1 and R.sup.2 aliphatic, alicyclic and aryl
hydrocarbon radicals in the general formula R.sup.1C(O)R.sup.2
include methyl, ethyl, propyl, isopropyl, butyl, isobutyl,
sec-butyl, tert-butyl, pentyl, isopentyl, neopentyl, tert-pentyl,
cyclopentyl, cyclohexyl, heptyl, octyl, nonyl, decyl, undecyl,
dodecyl and their configurational isomers, as well as phenyl,
benzyl, cumenyl, mesityl, tolyl, xylyl and phenethyl.
[0049] Representative ketone solubilizing agents include but are
not limited to: 2-butanone, 2-pentanone, acetophenone,
butyrophenone, hexanophenone, cyclohexanone, cycloheptanone,
2-heptanone, 3-heptanone, 5-methyl-2-hexanone, 2-octanone,
3-octanone, diisobutyl ketone, 4-ethylcyclohexanone, 2-nonanone,
5-nonanone, 2-decanone, 4-decanone, 2-decalone, 2-tridecanone,
dihexyl ketone and dicyclohexyl ketone.
[0050] Nitrile solubilizing agents of the present invention
comprise nitriles represented by the formula R.sup.1CN, wherein
R.sup.1 is selected from aliphatic, alicyclic or aryl hydrocarbon
radicals having from 5 to 12 carbon atoms, and wherein said
nitriles have a molecular weight of from about 90 to about 200
atomic mass units. R.sup.1 in said nitrile solubilizing agents is
preferably selected from aliphatic and alicyclic hydrocarbon
radicals having 8 to 10 carbon atoms. The molecular weight of said
nitrile solubilizing agents is preferably from about 120 to about
140 atomic mass units. R.sup.1 may optionally include substituted
hydrocarbon radicals, that is, radicals containing non-hydrocarbon
substituents selected from halogens (e.g., fluorine, chlorine) and
alkoxides (e.g. methoxy). R.sup.1 may optionally include
heteroatom-substituted hydrocarbon radicals, that is, radicals,
which contain the atoms nitrogen (aza-), oxygen (keto-, oxa-) or
sulfur (thia-) in a radical chain otherwise composed of carbon
atoms. In general, no more than three non-hydrocarbon substituents
and heteroatoms, and preferably no more than one, will be present
for each 10 carbon atoms in R.sup.1, and the presence of any such
non-hydrocarbon substituents and heteroatoms must be considered in
applying the aforementioned molecular weight limitations.
Representative R.sup.1 aliphatic, alicyclic and aryl hydrocarbon
radicals in the general formula R.sup.1CN include pentyl,
isopentyl, neopentyl, tert-pentyl, cyclopentyl, cyclohexyl, heptyl,
octyl, nonyl, decyl, undecyl, dodecyl and their configurational
isomers, as well as phenyl, benzyl, cumenyl, mesityl, tolyl, xylyl
and phenethyl.
[0051] Representative nitrile solubilizing agents include but are
not limited to: 1-cyanopentane, 2,2-dimethyl-4-cyanopentane,
1-cyanohexane, 1-cyanoheptane, 1-cyanooctane, 2-cyanooctane,
1-cyanononane, 1-cyanodecane, 2-cyanodecane, 1-cyanoundecane and
1-cyanododecane.
[0052] Chlorocarbon solubilizing agents of the present invention
comprise chlorocarbons represented by the formula RCl.sub.x,
wherein x is 1 or 2; R is selected from aliphatic and alicyclic
hydrocarbon radicals having 1 to 12 carbon atoms; and wherein said
chlorocarbons have a molecular weight of from about 100 to about
200 atomic mass units. The molecular weight of said chlorocarbon
solubilizing agents is preferably from about 120 to 150 atomic mass
units. Representative R aliphatic and alicyclic hydrocarbon
radicals in the general formula RCl.sub.x include methyl, ethyl,
propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl,
isopentyl, neopentyl, tert-pentyl, cyclopentyl, cyclohexyl, heptyl,
octyl, nonyl, decyl, undecyl, dodecyl and their configurational
isomers.
[0053] Representative chlorocarbon solubilizing agents include but
are not limited to: 3-(chloromethyl)pentane,
3-chloro-3-methylpentane, 1-chlorohexane, 1,6-dichlorohexane,
1-chloroheptane, 1-chlorooctane, 1-chlorononane, 1-chlorodecane,
and 1,1,1-trichlorodecane.
[0054] Ester solubilizing agents of the present invention comprise
esters represented by the general formula R.sup.1C(O)OR.sup.2,
wherein R.sup.1 and R.sup.2 are independently selected from linear
and cyclic, saturated and unsaturated, alkyl and aryl radicals.
Preferred esters consist essentially of the elements C, H and O,
have a molecular weight of from about 80 to about 550 atomic mass
units.
[0055] Representative esters include but are not limited to:
(CH.sub.3).sub.2CHCH.sub.2O(O)C(CH.sub.2).sub.2-4(O)COCH.sub.2CH(CH.sub.3-
).sub.2 (diisobutyl dibasic ester), ethyl hexanoate, ethyl
heptanoate, n-butyl propionate, n-propyl propionate, ethyl
benzoate, di-n-propyl phthalate, benzoic acid ethoxyethyl ester,
dipropyl carbonate, "Exxate 700" (a commercial C.sub.7 alkyl
acetate), "Exxate 800" (a commercial C.sub.8 alkyl acetate),
dibutyl phthalate, and tert-butyl acetate.
[0056] Lactone solubilizing agents of the present invention
comprise lactones represented by structures [A], [B], and [C]:
##STR00001##
[0057] These lactones contain the functional group --C(O)O-- in a
ring of six (A), or preferably five atoms (B), wherein for
structures [A] and [B], R.sub.1 through R.sub.8 are independently
selected from hydrogen or linear, branched, cyclic, bicyclic,
saturated and unsaturated hydrocarbyl radicals. Each R.sub.1 though
R.sub.8 may be connected forming a ring with another R.sub.1
through R.sub.8. The lactone may have an exocyclic alkylidene group
as in structure [C], wherein R.sub.1 through R.sub.6 are
independently selected from hydrogen or linear, branched, cyclic,
bicyclic, saturated and unsaturated hydrocarbyl radicals. Each
R.sub.1 though R.sub.6 may be connected forming a ring with another
R.sub.1 through R.sub.6. The lactone solubilizing agents have a
molecular weight range of from about 80 to about 300 atomic mass
units, preferred from about 80 to about 200 atomic mass units.
[0058] Representative lactone solubilizing agents include but are
not limited to the compounds listed in Table 5.
TABLE-US-00005 TABLE 5 Molecular Molecular Molecular Weight
Additive Structure Formula (amu)
(E,Z)-3-ethylidene-5-methyl-dihydro-furan-2-one ##STR00002##
C.sub.7H.sub.10O.sub.2 126
(E,Z)-3-propylidene-5-methyl-dihydro-furan-2-one ##STR00003##
C.sub.8H.sub.12O.sub.2 140
(E,Z)-3-butylidene-5-methyl-dihydro-furan-2-one ##STR00004##
C.sub.9H.sub.14O.sub.2 154
(E,Z)-3-pentylidene-5-methyl-dihydro-furan-2-one ##STR00005##
C.sub.10H.sub.16O.sub.2 168
(E,Z)-3-Hexylidene-5-methyl-dihydro-furan-2-one ##STR00006##
C.sub.11H.sub.18O.sub.2 182
(E,Z)-3-Heptylidene-5-methyl-dihydro-furan-2-one ##STR00007##
C.sub.12H.sub.20O.sub.2 196
(E,Z)-3-octylidene-5-methyl-dihydro-furan-2-one ##STR00008##
C.sub.13H.sub.22O.sub.2 210
(E,Z)-3-nonylidene-5-methyl-dihydro-furan-2-one ##STR00009##
C.sub.14H.sub.24O.sub.2 224
(E,Z)-3-decylidene-5-methyl-dihydro-furan-2-one ##STR00010##
C.sub.15H.sub.26O.sub.2 238
(E,Z)-3-(3,5,5-trimethylhexylidene)-5-methyl-dihydrofuran-2-one
##STR00011## C.sub.14H.sub.24O.sub.2 224
(E,Z)-3-cyclohexylmethylidene-5-methyl-dihydrofuran-2-one
##STR00012## C.sub.12H.sub.18O.sub.2 194 gamma-octalactone
##STR00013## C.sub.8H.sub.14O.sub.2 142 gamma-nonalactone
##STR00014## C.sub.9H.sub.16O.sub.2 156 gamma-decalactone
##STR00015## C.sub.10H.sub.18O.sub.2 170 gamma-undecalactone
##STR00016## C.sub.11H.sub.20O.sub.2 184 gamma-dodecalactone
##STR00017## C.sub.12H.sub.22O.sub.2 198 3-hexyldihydro-furan-2-one
##STR00018## C.sub.10H.sub.18O.sub.2 170
3-heptyldihydro-furan-2-one ##STR00019## C.sub.11H.sub.20O.sub.2
184 cis-3-ethyl-5-methyl-dihydro-furan-2-one ##STR00020##
C.sub.7H.sub.12O.sub.2 128
cis-(3-propyl-5-methyl)-dihydro-furan-2-one ##STR00021##
C.sub.8H.sub.14O.sub.2 142
cis-(3-butyl-5-methyl)-dihydro-furan-2-one ##STR00022##
C.sub.9H.sub.16O.sub.2 156
cis-(3-pentyl-5-methyl)-dihydro-furan-2-one ##STR00023##
C.sub.10H.sub.18O.sub.2 170
cis-3-hexyl-5-methyl-dihydro-furan-2-one ##STR00024##
C.sub.11H.sub.20O.sub.2 184
cis-3-heptyl-5-methyl-dihydro-furan-2-one ##STR00025##
C.sub.12H.sub.22O.sub.2 198
cis-3-octyl-5-methyl-dihydro-furan-2-one ##STR00026##
C.sub.13H.sub.24O.sub.2 212
cis-3-(3,5,5-trimethylhexyl)-5-methyl-dihydro-furan-2-one
##STR00027## C.sub.14H.sub.26O.sub.2 226
cis-3-cyclohexylmethyl-5-methyl-dihydro-furan-2-one ##STR00028##
C.sub.12H.sub.20O.sub.2 196 5-methyl-5-hexyl-dihydro-furan-2-one
##STR00029## C.sub.11H.sub.20O.sub.2 184
5-methyl-5-octyl-dihydro-furan-2-one ##STR00030##
C.sub.13H.sub.24O.sub.2 212 Hexahydro-isobenzofuran-1-one
##STR00031## C.sub.8H.sub.12O.sub.2 140 delta-decalactone
##STR00032## C.sub.10H.sub.18O.sub.2 170 delta-undecalactone
##STR00033## C.sub.11H.sub.20O.sub.2 184 delta-dodecalactone
##STR00034## C.sub.12H.sub.22O.sub.2 198 mixture of
4-hexyl-dihydrofuran-2-one and3-hexyl-dihydro-furan-2-one
##STR00035## C.sub.10H.sub.18O.sub.2 170
[0059] Lactone solubilizing agents generally have a kinematic
viscosity of less than about 7 centistokes at 40.degree. C. For
instance, gamma-undecalactone has kinematic viscosity of 5.4
centistokes and cis-(3-hexyl-5-methyl)dihydrofuran-2-one has
viscosity of 4.5 centistokes, both at 40.degree. C. Lactone
solubilizing agents may be available commercially or prepared by
methods as described in published U.S. patent application
20060030719, which is herein incorporated by reference in its
entirety
[0060] Aryl ether solubilizing agents of the present invention
comprise aryl ethers represented by the formula R.sup.1OR.sup.2,
wherein: R.sup.1 is selected from aryl hydrocarbon radicals having
from 6 to 12 carbon atoms; R.sup.2 is selected from aliphatic
hydrocarbon radicals having from 1 to 4 carbon atoms; and wherein
said aryl ethers have a molecular weight of from about 100 to about
150 atomic mass units. Representative R.sup.1 aryl radicals in the
general formula R.sup.1OR.sup.2 include phenyl, biphenyl, cumenyl,
mesityl, tolyl, xylyl, naphthyl and pyridyl. Representative R.sup.2
aliphatic hydrocarbon radicals in the general formula
R.sup.1OR.sup.2 include methyl, ethyl, propyl, isopropyl, butyl,
isobutyl, sec-butyl and tert-butyl. Representative aromatic ether
solubilizing agents include but are not limited to: methyl phenyl
ether (anisole), 1,3-dimethyoxybenzene, ethyl phenyl ether and
butyl phenyl ether.
[0061] Fluoroether solubilizing agents of the present invention
comprise those represented by the general formula
R.sup.1OCF.sub.2CF.sub.2H, wherein R.sup.1 is selected from
aliphatic, alicyclic, and aromatic hydrocarbon radicals having from
about 5 to about 15 carbon atoms, preferably primary, linear,
saturated, alkyl radicals. Representative fluoroether solubilizing
agents include but are not limited to:
C.sub.8H.sub.17OCF.sub.2CF.sub.2H and
C.sub.6H.sub.13OCF.sub.2CF.sub.2H. It should be noted that if the
refrigerant is a fluoroether, then the solubilizing agent may not
be the same fluoroether.
[0062] Fluoroether solubilizing agents may further comprise ethers
derived from fluoro-olefins and polyols. The fluoro-olefins may be
of the type CF.sub.2.dbd.CXY, wherein X is hydrogen, chlorine or
fluorine, and Y is chlorine, fluorine, CF.sub.3 or OR.sub.f,
wherein R.sub.f is CF.sub.3, C.sub.2F.sub.5, or C.sub.3F.sub.7.
Representative fluoro-olefins are tetrafluoroethylene,
chlorotrifluoroethylene, hexafluoropropylene, and
perfluoromethylvinyl ether. The polyols may be linear or branched.
Linear polyols may be of the type
HOCH.sub.2(CHOH).sub.x(CRR').sub.yCH.sub.2OH, wherein R and R' are
hydrogen, or CH.sub.3, or C.sub.2H.sub.5 and wherein x is an
integer from 0-4, and y is an integer from 0-4. Branched polyols
may be of the type
C(OH).sub.t(R).sub.u(CH2OH).sub.v[(CH2).sub.mCH2OH].sub.w, wherein
R may be hydrogen, CH.sub.3 or C.sub.2H.sub.5, m may be an integer
from 0 to 3, t and u may be 0 or 1, v and w are integers from 0 to
4, and also wherein t+u+v+w=4. Representative polyols are
trimethylol propane, pentaerythritol, butanediol, and ethylene
glycol.
[0063] 1,1,1-Trifluoroalkane solubilizing agents of the present
invention comprise 1,1,1-trifluoroalkanes represented by the
general formula CF.sub.3R.sup.1, wherein R.sup.1 is selected from
aliphatic and alicyclic hydrocarbon radicals having from about 5 to
about 15 carbon atoms, preferably primary, linear, saturated alkyl
radicals. Representative 1,1,1-trifluoroalkane solubilizing agents
include but are not limited to: 1,1,1-trifluorohexane and
1,1,1-trifluorododecane.
[0064] Solubilizing agents of the present invention may be present
as a single compound, or may be present as a mixture of more than
one solubilizing agent. Mixtures of solubilizing agents may contain
two solubilizing agents from the same class of compounds, as for
example, two lactones, or two solubilizing agents from two
different classes, as for example, a lactone and a polyoxyalkylene
glycol ether.
[0065] In the present compositions comprising a refrigerant and a
UV fluorescent dye, or comprising heat transfer fluid and a UV
fluorescent dye, from about 0.001 weight percent to about 1.0
weight percent of the compositions is UV dye, preferably from about
0.005 weight percent to about 0.5 weight percent, and most
preferably from 0.01 weight percent to about 0.25 weight
percent.
[0066] Solubility of these UV fluorescent dyes in refrigerants and
heat transfer fluids may be poor. Therefore, methods for
introducing these dyes into the refrigeration or air-conditioning
apparatus have been awkward, costly and time consuming. U.S. Pat.
No. RE 36,951 describes a method, which utilizes a dye powder,
solid pellet or slurry of dye that may be inserted into a component
of the refrigeration or air-conditioning apparatus. As refrigerant
and lubricant are circulated through the apparatus, the dye is
dissolved or dispersed and carried throughout the apparatus.
Numerous other methods for introducing dye into a refrigeration or
air-conditioning apparatus are described in the literature.
[0067] Ideally, the UV fluorescent dye could be dissolved in the
refrigerant itself thereby not requiring any specialized method for
introduction to the refrigeration or air-conditioning apparatus.
The present invention relates to compositions including UV
fluorescent dye, which may be introduced into the system in the
refrigerant. The inventive compositions will allow the storage and
transport of dye-containing refrigerant and heat transfer fluid
even at low temperatures while maintaining the dye in solution.
[0068] In the present compositions comprising refrigerant, UV
fluorescent dye and solubilizing agent, or comprising heat transfer
fluid, UV fluorescent dye and solubilizing agent, from about 1 to
about 50 weight percent, preferably from about 2 to about 25 weight
percent, and most preferably from about 5 to about 15 weight
percent of the combined composition is solubilizing agent in the
refrigerant or heat transfer fluid. In the compositions of the
present invention the UV fluorescent dye is present in a
concentration from about 0.001 weight percent to about 1.0 weight
percent in the refrigerant or heat transfer fluid, preferably from
0.005 weight percent to about 0.5 weight percent, and most
preferably from 0.01 weight percent to about 0.25 weight
percent.
[0069] Optionally, commonly used refrigeration or air-conditioning
system additives may be added, as desired, to compositions of the
present invention in order to enhance performance and system
stability. These additives are known in the field of refrigeration
and air-conditioning, and include, but are not limited to, anti
wear agents, extreme pressure lubricants, corrosion and oxidation
inhibitors, metal surface deactivators, free radical scavengers,
and foam control agents. In general, these additives are present in
the inventive compositions in small amounts relative to the overall
composition. Typically concentrations of from less than about 0.1
weight percent to as much as about 3 weight percent of each
additive are used. These additives are selected on the basis of the
individual system requirements. These additives include members of
the triaryl phosphate family of EP (extreme pressure) lubricity
additives, such as butylated triphenyl phosphates (BTPP), or other
alkylated triaryl phosphate esters, e.g. Syn-0-Ad 8478 from Akzo
Chemicals, tricresyl phosphates and related compounds.
Additionally, the metal dialkyl dithiophosphates (e.g. zinc dialkyl
dithiophosphate (or ZDDP), Lubrizol 1375 and other members of this
family of chemicals may be used in compositions of the present
invention. Other antiwear additives include natural product oils
and asymmetrical polyhydroxyl lubrication additives, such as
Synergol TMS (International Lubricants). Similarly, stabilizers
such as anti oxidants, free radical scavengers, and water
scavengers may be employed. Compounds in this category can include,
but are not limited to, butylated hydroxy toluene (BHT) and
epoxides.
[0070] Solubilizing agents such as ketones may have an
objectionable odor, which can be masked by addition of an odor
masking agent or fragrance. Typical examples of odor masking agents
or fragrances may include Evergreen, Fresh Lemon, Cherry, Cinnamon,
Peppermint, Floral or Orange Peel, all commercially available, as
well as d-limonene and pinene. Such odor masking agents may be used
at concentrations of from about 0.001% to as much as about 15% by
weight based on the combined weight of odor masking agent and
solubilizing agent.
[0071] The present invention further relates to a method of using
the refrigerant or heat transfer fluid compositions further
comprising ultraviolet fluorescent dye, and optionally,
solubilizing agent, in refrigeration or air-conditioning apparatus.
The method comprises introducing the refrigerant or heat transfer
fluid composition into the refrigeration or air-conditioning
apparatus. This may be done by dissolving the UV fluorescent dye in
the refrigerant or heat transfer fluid composition in the presence
of a solubilizing agent and introducing the combination into the
apparatus. Alternatively, this may be done by combining a
solubilizing agent and a UV fluorescent dye and introducing said
combination into refrigeration or air-conditioning apparatus
containing refrigerant and/or heat transfer fluid. The resulting
composition may be used in the refrigeration or air-conditioning
apparatus.
[0072] The present invention further relates to a method of using
the refrigerant or heat transfer fluid compositions comprising
ultraviolet fluorescent dye to detect leaks. The presence of the
dye in the compositions allows for detection of leaking refrigerant
in the refrigeration or air-conditioning apparatus. Leak detection
helps to address, resolve or prevent inefficient operation of the
apparatus or system or equipment failure. Leak detection also helps
one contain chemicals used in the operation of the apparatus.
[0073] The method comprises providing the composition comprising
refrigerant and ultra-violet fluorescent dye, or comprising heat
transfer fluid and ultra-violet fluorescent dye as described
herein, and optionally, a solubilizing agent as described herein,
to refrigeration and air-conditioning apparatus and employing a
suitable means for detecting the UV fluorescent dye-containing
refrigerant. Suitable means for detecting the dye include, but are
not limited to, an ultra-violet lamp, often referred to as a "black
light" or "blue light". Such ultra-violet lamps are commercially
available from numerous sources specifically designed for this
purpose. Once the ultra-violet fluorescent dye containing
composition has been introduced to the refrigeration or
air-conditioning apparatus and has been allowed to circulate
throughout the system, a leak can be found by shining said
ultra-violet lamp on the apparatus and observing the fluorescence
of the dye in the vicinity of any leak point.
[0074] The present invention further relates to a method of using
the compositions of the present invention for producing
refrigeration or heat, wherein the method comprises producing
refrigeration by evaporating said composition in the vicinity of a
body to be cooled and thereafter condensing said composition; or
producing heat by condensing said composition in the vicinity of
the body to be heated and thereafter evaporating said composition.
Where refrigeration or heat transfer fluid composition with an
ultra-violet fluorescent dye, and/or a solubilizing agent, the
refrigerant or heat transfer fluid component of the composition is
evaporated and thereafter condensed to produce refrigeration, or
condensed and thereafter evaporated to produce heat.
[0075] Mechanical refrigeration is primarily an application of
thermodynamics wherein a cooling medium, such as a refrigerant,
goes through a cycle so that it can be recovered for reuse.
Commonly used cycles include vapor-compression, absorption,
steam-jet or steam-ejector, and air.
[0076] Vapor-compression refrigeration systems include an
evaporator, a compressor, a condenser, and an expansion device. A
vapor-compression cycle re-uses refrigerant in multiple steps
producing a cooling effect in one step and a heating effect in a
different step. The cycle can be described simply as follows.
Liquid refrigerant enters an evaporator through an expansion
device, and the liquid refrigerant boils in the evaporator at a low
temperature to form a gas and produce cooling. The low-pressure gas
enters a compressor where the gas is compressed to raise its
pressure and temperature. The higher-pressure (compressed) gaseous
refrigerant then enters the condenser in which the refrigerant
condenses and discharges its heat to the environment. The
refrigerant returns to the expansion device through which the
liquid expands from the higher-pressure level in the condenser to
the low-pressure level in the evaporator, thus repeating the
cycle.
[0077] There are various types of compressors that may be used in
refrigeration applications. Compressors can be generally classified
as reciprocating, rotary, jet, centrifugal, scroll, screw or
axial-flow, depending on the mechanical means to compress the
fluid, or as positive-displacement (e.g., reciprocating, scroll or
screw) or dynamic (e.g., centrifugal or jet), depending on how the
mechanical elements act on the fluid to be compressed.
[0078] Either positive displacement or dynamic compressors may be
used in the present inventive process. A centrifugal type
compressor is the preferred equipment for the present refrigerant
compositions.
[0079] A centrifugal compressor uses rotating elements to
accelerate the refrigerant radially, and typically includes an
impeller and diffuser housed in a casing. Centrifugal compressors
usually take fluid in at an impeller eye, or central inlet of a
circulating impeller, and accelerate it radially outward. Some
static pressure rise occurs in the impeller, but most of the
pressure rise occurs in the diffuser section of the casing, where
velocity is converted to static pressure. Each impeller-diffuser
set is a stage of the compressor. Centrifugal compressors are built
with from 1 to 12 or more stages, depending on the final pressure
desired and the volume of refrigerant to be handled.
[0080] The pressure ratio, or compression ratio, of a compressor is
the ratio of absolute discharge pressure to the absolute inlet
pressure. Pressure delivered by a centrifugal compressor is
practically constant over a relatively wide range of
capacities.
[0081] Positive displacement compressors draw vapor into a chamber,
and the chamber decreases in volume to compress the vapor. After
being compressed, the vapor is forced from the chamber by further
decreasing the volume of the chamber to zero or nearly zero. A
positive displacement compressor can build up a pressure, which is
limited only by the volumetric efficiency and the strength of the
parts to withstand the pressure.
[0082] Unlike a positive displacement compressor, a centrifugal
compressor depends entirely on the centrifugal force of the
high-speed impeller to compress the vapor passing through the
impeller. There is no positive displacement, but rather what is
called dynamic-compression.
[0083] The pressure a centrifugal compressor can develop depends on
the tip speed of the impeller. Tip speed is the speed of the
impeller measured at its tip and is related to the diameter of the
impeller and its revolutions per minute. The capacity of the
centrifugal compressor is determined by the size of the passages
through the impeller. This makes the size of the compressor more
dependent on the pressure required than the capacity.
[0084] Because of its high-speed operation, a centrifugal
compressor is fundamentally a high volume, low-pressure machine. A
centrifugal compressor works best with a low-pressure refrigerant,
such as trichlorofluoromethane (CFC-11) or
1,2,2-trichlorotrifluoroethane (CFC-113).
[0085] Large centrifugal compressors typically operate at 3000 to
7000 revolutions per minute (rpm). Small turbine centrifugal
compressors are designed for high speeds, from about 40,000 to
about 70,000 (rpm), and have small impeller sizes, typically less
than 0.15 meters.
[0086] A multi-stage impeller may be used in a centrifugal
compressor to improve compressor efficiency thus requiring less
power in use. For a two-stage system, in operation, the discharge
of the first stage impeller goes to the suction intake of a second
impeller. Both impellers may operate by use of a single shaft (or
axle). Each stage can build up a compression ratio of about 4 to 1;
that is, the absolute discharge pressure can be four times the
absolute suction pressure. An example of a two-stage centrifugal
compressor system, in this case for automotive applications, is
described in U.S. Pat. No. 5,065,990, incorporated herein by
reference.
[0087] The compositions of the present invention suitable for use
in a refrigeration or air-conditioning systems employing a
centrifugal compressor comprise at least one of: [0088] PFBE and
2,2-dimethylbutane; [0089] PFBE and 2,3-dimethylbutane; [0090] PFBE
and 2-methylpentane; [0091] PFBE and 3-methylpentane; [0092] PFBE
and cyclopentane; and [0093] PFBE and methylcyclopentane.
[0094] These above-listed compositions are also suitable for use in
a multi-stage centrifugal compressor, preferably a two-stage
centrifugal compressor apparatus.
[0095] The compositions of the present invention may be used in
stationary air-conditioning, heat pumps or mobile air-conditioning
and refrigeration systems. Stationary air-conditioning and heat
pump applications include window, ductless, ducted, packaged
terminal, chillers and commercial, including packaged rooftop.
Refrigeration applications include domestic or home refrigerators
and freezers, ice machines, self-contained coolers and freezers,
walk-in coolers and freezers and transport refrigeration
systems.
[0096] The compositions of the present invention may additionally
be used in air-conditioning, heating and refrigeration systems that
employ fin and tube heat exchangers, microchannel heat exchangers
and vertical or horizontal single pass tube or plate type heat
exchangers.
[0097] Conventional microchannel heat exchangers may not be ideal
for the low pressure refrigerant compositions of the present
invention. The low operating pressure and density result in high
flow velocities and high frictional losses in all components. In
these cases, the evaporator design may be modified. Rather than
several microchannel slabs connected in series (with respect to the
refrigerant path) a single slab/single pass heat exchanger
arrangement may be used. Therefore, a preferred heat exchanger for
the low pressure refrigerants of the present invention is a single
slab/single pass heat exchanger.
[0098] In addition to two-stage or other multi-stage centrifugal
compressor apparatus, the following compositions of the present
invention are suitable for use in refrigeration or air-conditioning
apparatus employing a single slab/single pass heat exchanger:
[0099] PFBE and 2,2-dimethylbutane; [0100] PFBE and
2,3-dimethylbutane; [0101] PFBE and 2-methylpentane; [0102] PFBE
and 3-methylpentane; [0103] PFBE and cyclopentane; and [0104] PFBE
and methylcyclopentane.
[0105] The compositions of the present invention are particularly
useful in small turbine centrifugal compressors (mini-centrifugal
compressors), which can be used in auto and window
air-conditioning, heat pumps, or transport refrigeration, as well
as other applications. These high efficiency mini-centrifugal
compressors may be driven by an electric motor and can therefore be
operated independently of the engine speed. A constant compressor
speed allows the system to provide a relatively constant cooling
capacity at all engine speeds. This provides an opportunity for
efficiency improvements especially at higher engine speeds as
compared to a conventional R-134a automobile air-conditioning
system. When the cycling operation of conventional systems at high
driving speeds is taken into account, the advantage of these low
pressure systems becomes even greater.
[0106] Alternatively, rather than use electrical power, the
mini-centrifugal compressor may be powered by an engine exhaust gas
driven turbine or a ratioed gear drive assembly with ratioed belt
drive. The electrical power available in current automobile design
is about 14 volts, but the new mini-centrifugal compressor requires
electrical power of about 50 volts. Therefore, use of an
alternative power source would be advantageous. A refrigeration or
air-conditioning apparatus powered by an engine exhaust gas driven
turbine is described in detail in U.S. patent application Ser. No.
11/367,517, filed Mar. 2, 2006, incorporated herein by reference. A
refrigeration or air-conditioning apparatus powered by a ratioed
gear drive assembly is described in detail in U.S. patent
application Ser. No. 11/378,832, filed Mar. 17, 2006, incorporated
herein by reference.
[0107] In cleaning apparati, such as vapor degreasers or defluxers,
compositions may be lost during operation through leaks in shaft
seals, hose connections, soldered joints and broken lines. In
addition, the working composition may be released to the atmosphere
during maintenance procedures on equipment. If the composition is
not a pure compound or azeotropic or azeotrope-like composition,
the composition may change when leaked or discharged to the
atmosphere from the equipment, which may cause the composition
remaining in the equipment to become flammable or to exhibit
unacceptable performance. Accordingly, it is desirable to use as a
cleaning composition a single fluorinated hydrocarbon or an
azeotropic or azeotrope-like composition that fractionates to a
negligible degree upon leak or boil-off.
[0108] Some of the low pressure refrigerant fluids of the present
invention may be suitable as drop-in replacements for CFC-113 in
existing centrifugal equipment.
[0109] In one embodiment, the present invention relates to a
process for producing refrigeration comprising evaporating the
compositions of the present invention in the vicinity of a body to
be cooled, and thereafter condensing said compositions.
[0110] In another embodiment, the present invention relates to a
process for producing heat comprising condensing the compositions
of the present invention in the vicinity of a body to be heated,
and thereafter evaporating said compositions.
[0111] In yet another embodiment, the present invention relates to
a process for transfer of heat from a heat source to a heat sink
wherein the compositions of the present invention serve as heat
transfer fluids. Said process for heat transfer comprises
transferring the compositions of the present invention from a heat
source to a heat sink.
[0112] Heat transfer fluids are utilized to transfer, move or
remove heat from one space, location, object or body to a different
space, location, object or body by radiation, conduction, or
convection. A heat transfer fluid may function as a secondary
coolant by providing means of transfer for cooling (or heating)
from a remote refrigeration (or heating) system. In some systems,
the heat transfer fluid may remain in a constant state throughout
the transfer process (i.e., not evaporate or condense).
Alternatively, evaporative cooling processes may utilize heat
transfer fluids as well.
[0113] A heat source may be defined as any space, location, object
or body from which it is desirable to transfer, move or remove
heat. Examples of heat sources may be spaces (open or enclosed)
requiring refrigeration or cooling, such as refrigerator or freezer
cases in a supermarket, building spaces requiring air-conditioning,
or the passenger compartment of an automobile requiring
air-conditioning. A heat sink may be defined as any space,
location, object or body capable of absorbing heat. A vapor
compression refrigeration system is one example of such a heat
sink.
[0114] In another embodiment, the present invention relates to a
process to produce cooling comprising compressing a composition of
the present invention, in a mini-centrifugal compressor powered by
an engine exhaust gas driven turbine; condensing said composition;
and thereafter evaporating said composition in the vicinity of a
body to be cooled.
[0115] In yet another embodiment, the present invention relates to
a process to produce cooling comprising compressing a composition
of the present invention, in a mini-centrifugal compressor powered
by a ratioed gear drive assembly with a ratioed belt drive;
condensing said composition; and thereafter evaporating said
composition in the vicinity of a body to be cooled. In an
embodiment of the invention, the present inventive azeotropic
compositions are effective cleaning agents, defluxers and
degreasers. In particular, the present inventive azeotropic
compositions are useful when de-fluxing circuit boards with
components such as Flip chip, .quadrature.BGA (ball grid array),
and Chip scale or other advanced high-density packaging components.
Flip chips, .quadrature.BGA, and Chip scale are terms that describe
high density packaging components used in the semi-conductor
industry and are well understood by those working in the field.
[0116] In another embodiment the present invention relates to a
process for removing residue from a surface or substrate,
comprising: contacting the surface or substrate with a composition
of the present invention and recovering the surface or substrate
from the composition.
[0117] In a process embodiment of the invention, the surface or
substrate may be an integrated circuit device, in which case, the
residue comprises rosin flux or oil. The integrated circuit device
may be a circuit board with various types of components, such as
Flip chips, .quadrature.BGAs, or Chip scale packaging components.
The surface or substrate may additionally be a metal surface such
as stainless steel. The rosin flux may be any type commonly used in
the soldering of integrated circuit devices, including but not
limited to RMA (rosin mildly activated), RA (rosin activated), WS
(water soluble), and OA (organic acid). Oil residues include but
are not limited to mineral oils, motor oils, and silicone oils.
[0118] In the inventive process the means for contacting the
surface or substrate is not critical and may be accomplished by
immersion of the device in a bath containing the composition,
spraying the device with the composition or wiping the device with
a substrate that has been wet with the composition. Alternatively,
the composition may also be used in a vapor degreasing or defluxing
apparatus designed for such residue removal. Such vapor degreasing
or defluxing equipment is available from various suppliers such as
Forward Technology (a subsidiary of the Crest Group, Trenton,
N.J.), Trek Industries (Azusa, Calif.), and Ultronix, Inc.
(Hatfield, Pa.) among others.
[0119] An effective composition for removing residue from a surface
would be one that had a Kauri-Butanol value (Kb) of at least about
10, preferably about 40, and even more preferably about 100. The
Kauri-Butanol value (Kb) for a given composition reflects the
ability of said composition to solubilize various organic residues
(e.g., machine and conventional refrigeration lubricants). The Kb
value may be determined by ASTM D-1133-94.
[0120] The following Examples are meant to illustrate the invention
and are not meant to be limiting.
EXAMPLES
Example 1
Impact of Vapor Leakage
[0121] A vessel is charged with an initial composition at a
specified temperature, and the initial vapor pressure of the
composition is measured. The composition is allowed to leak from
the vessel, while the temperature is held constant, until 50 weight
percent of the initial composition is removed, at which time the
vapor pressure of the composition remaining in the vessel is
measured. Results are summarized in Table 6 below.
TABLE-US-00006 TABLE 6 After 50% Leak After 50% Leak Compounds
Initial Initial wt % A/wt % B Psia kPa Psia kPa Delta P %
PFBE/2,2-dimethylbutane (50.0.degree. C.) 0/100 14.82 102.18 14.82
102.18 0.0% 1/99 14.80 102.04 14.80 102.04 0.0% 10/90 14.69 101.28
14.67 101.15 0.1% 20/80 14.54 100.25 14.50 99.97 0.3% 40/60 14.16
97.63 14.05 96.87 0.8% 60/40 13.59 93.70 13.40 92.39 1.4% 80/20
12.64 87.15 12.40 85.50 1.9% 90/10 11.89 81.98 11.69 80.60 1.7%
99/1 10.93 75.36 10.90 75.15 0.3% 100/0 10.80 74.46 10.80 74.46
0.0% PFBE/2,3-dimethylbutane (57.2.degree. C.) 61.7/38.3 14.72
101.49 14.72 101.49 0.0% 80/20 14.60 100.66 14.59 100.60 0.1% 90/10
14.37 99.08 14.34 98.87 0.2% 99/1 13.91 95.91 13.90 95.84 0.1%
100/0 13.84 95.42 13.84 95.42 0.0% 40/60 14.64 100.94 14.63 100.87
0.1% 20/80 14.50 99.97 14.49 99.91 0.1% 10/90 14.42 99.42 14.41
99.35 0.1% 1/99 14.34 98.87 14.34 98.87 0.0% 0/100 14.33 98.80
14.33 98.80 0.0% PFBE/2-methylpentane (58.1.degree. C.) 79.1/20.9
14.70 101.35 14.70 101.35 0.0% 90/10 14.61 100.73 14.61 100.73 0.0%
95/5 14.49 99.91 14.47 99.77 0.1% 99/1 14.32 98.73 14.31 98.66 0.1%
100/0 14.26 98.32 14.26 98.32 0.0% 60/40 14.57 100.46 14.55 100.32
0.1% 40/60 14.30 98.60 14.26 98.32 0.3% 20/80 14.01 96.60 13.97
96.32 0.3% 10/90 13.86 95.56 13.83 95.36 0.2% 1/99 13.72 94.60
13.72 94.60 0.0% 0/100 13.71 94.53 13.71 94.53 0.0%
PFBE/3-methylpentane (58.7.degree. C.) 90.0/10.0 14.71 101.42 14.71
101.42 0.0% 95/5 14.68 101.22 14.68 101.22 0.0% 99/1 14.58 100.53
14.58 100.53 0.0% 100/0 14.55 100.32 14.55 100.32 0.0% 60/40 14.21
97.98 14.12 97.35 0.6% 40/60 13.71 94.53 13.56 93.49 1.1% 20/80
13.19 90.94 13.08 90.18 0.8% 10/90 12.94 89.22 12.87 88.74 0.5%
1/99 12.72 87.70 12.71 87.63 0.1% 0/100 12.69 87.50 12.69 87.50
0.0% PFBE/cyclopentane (42.5.degree. C.) 61.9/38.1 14.72 101.49
14.72 101.49 0.0% 80/20 14.38 99.15 13.73 94.67 4.5% 85/15 14.00
96.53 12.66 87.29 9.6% 86/14 13.89 95.77 12.37 85.29 10.9% 100/0
8.22 56.68 8.22 56.68 0.0% 40/60 14.50 99.97 13.91 95.91 4.1% 30/70
14.24 98.18 12.88 88.81 9.6% 29/71 14.20 97.91 12.78 88.12 10.0%
0/100 11.70 80.67 11.70 80.67 0.0% PFBE/methylcyclopentane
(57.6.degree. C.) 88.3/11.7 14.70 101.35 14.70 101.35 0.0% 95/5
14.70 101.35 14.70 101.35 0.0% 99/1 14.70 101.35 14.70 101.35 0.0%
100/0 8.75 60.33 8.75 60.33 0.0% 60/40 14.70 101.35 14.70 101.35
0.0% 50/50 14.70 101.35 14.70 101.35 0.0% 49/51 5.96 41.09 5.96
41.09 0.0% 0/100 9.28 63.98 9.28 63.98 0.0%
[0122] The results show the difference in vapor pressure between
the original composition and the composition remaining after 50
weight percent has been removed is less then about 10 percent for
compositions of the present invention. This indicates compositions
of the present invention are azeotropic or near-azeotrope.
Example 2
Tip Speed to Develop Pressure
[0123] Tip speed can be estimated by making some fundamental
relationships for refrigeration equipment that use centrifugal
compressors. The torque an impeller ideally imparts to a gas is
defined as
T=m*(v.sub.2*r.sub.2-v.sub.1*r.sub.1) Equation 1
where
[0124] T=torque, Newton-meters
[0125] m=mass rate of flow, kg/sec
[0126] v.sub.2=tangential velocity of refrigerant leaving impeller
(tip speed), meters/sec
[0127] r.sub.2=radius of exit impeller, meters
[0128] v.sub.1=tangential velocity of refrigerant entering
impeller, meters/sec
[0129] r.sub.1=radius of inlet of impeller, meters
[0130] Assuming the refrigerant enters the impeller in an
essentially axial direction, the tangential component of the
velocity v.sub.1=0, therefore
T=m*v.sub.2*r.sub.2 Equation 2
[0131] The power required at the shaft is the product of the torque
and the rotative speed
P=T*.omega. Equation 3
where
[0132] P=power, W
[0133] .omega.=angular velocity, radians/s
therefore,
P=T*w=m*v.sub.2*r.sub.2*.omega. Equation 4
[0134] At low refrigerant flow rates, the tip speed of the impeller
and the tangential velocity of the refrigerant are nearly
identical; therefore
r.sub.2*w=v.sub.2 Equation 5
and
P=m*v.sub.2*v.sub.2 Equation 6
[0135] Another expression for ideal power is the product of the
mass rate of flow and the isentropic work of compression,
P=m*H.sub.i*(1000 J/kJ) Equation 7
where
[0136] H.sub.i=Difference in enthalpy of the refrigerant from a
saturated vapor at the evaporating conditions to saturated
condensing conditions, kJ/kg.
[0137] Combining the two expressions Equation 6 and 7 produces,
v.sub.2*v.sub.2=1000*H.sub.i Equation 8
[0138] Although Equation 8 is based on some fundamental
assumptions, it provides a good estimate of the tip speed of the
impeller and provides an important way to compare tip speeds of
refrigerants.
[0139] The table below shows theoretical tip speeds that are
calculated for 1,2,2-trichlorotrifluoroethane (CFC-113) and
compositions of the present invention. The conditions assumed for
this comparison are:
TABLE-US-00007 Evaporator temperature 40.0.degree. F. (4.4.degree.
C.) Condenser temperature 110.0.degree. F. (43.3.degree. C.) Liquid
subcool temperature 10.0.degree. F. (5.5.degree. C.) Return gas
temperature 75.0.degree. F. (23.8.degree. C.) Compressor efficiency
is 70%
[0140] These are typical conditions under which small turbine
centrifugal compressors perform.
TABLE-US-00008 TABLE 7 Hi* Hi* V2 Wt Hi 0.7 0.7 rel Refrigerant Wt
% % Btu/ Btu/ KJ/ V2 to CFC- Composition PFBE B lb lb Kg m/s 113
CFC-113 100 10.92 7.6 17.8 133.3 na PFBE plus B: 2,2-dimethylbutane
50.0 50.0 20.45 14.3 33.3 182.5 137% 2,3-dimethylbutane 61.7 38.3
19.31 13.5 31.4 177.3 133% 2-methylpentane 79.1 20.9 15.98 11.2
26.0 161.3 121% 3-methylpentane 90.0 10.0 14.33 10.0 23.3 152.7
115% cyclopentane 61.9 38.1 18.3 12.8 29.8 172.6 129%
methylcyclopentane 88.3 11.7 14.51 10.2 23.6 153.7 115%
[0141] The Example shows that compounds of the present invention
have tip speeds within about +/-40 percent of CFC-113 and would be
effective replacements for CFC-113 with minimal compressor design
changes. Compounds with tip speeds within +/-25 percent of CFC-113
are preferred.
Example 3
Performance Data
[0142] The following table shows the performance of various
refrigerants compared to CFC-113. The data are based on the
following conditions.
TABLE-US-00009 Evaporator temperature 40.0.degree. F. (4.4.degree.
C.) Condenser temperature 110.0.degree. F. (43.3.degree. C.)
Subcool temperature 10.0.degree. F. (5.5.degree. C.) Return gas
temperature 75.0.degree. F. (23.8.degree. C.) Compressor efficiency
is 70%
TABLE-US-00010 TABLE 8 Compr Compr Evap Evap Cond Cond Disch Disch
Capacity wt % wt % Pres Pres Pres Pres Temp Ttemp (Btu/ Capacity
Composition PFBE B (Psia) (kPa) (Psia) (kPa) (F.) (C.) COP min)
(kW) PFBE 1.6 11 9.6 66 130.7 54.8 10.0 3.92 0.18 CFC-113 2.7 19
12.8 88 156.3 69.1 14.8 4.18 0.26 PFBE plus B: 2,2-dimethylbutane
50.0 50.0 2.5 17 11.4 79 135.6 57.6 14.4 4.01 0.25
2,3-dimethylbutane 61.7 38.3 1.9 13 9.2 64 135.2 57.3 11.4 4.01
0.20 2-methylpentane 79.1 20.9 1.7 12 8.8 61 135.3 57.4 10.7 4.01
0.19 3-methylpentane 90.0 10.0 1.6 11 8.6 59 133.2 56.2 10.2 3.97
0.18 cyclopentane 61.9 38.1 3.4 23 15.2 105 142.2 61.2 19.7 4.06
0.35 methylcyclopentane 88.3 11.7 1.7 12 8.9 62 133.8 56.6 10.7
3.98 0.19
[0143] Data show the compositions of the present invention have
evaporator and condenser pressures similar to CFC-113. Some
compositions also have higher capacity or energy efficiency (COP)
than CFC-113.
[0144] While specific embodiments of the invention have been shown
and described, further modifications and improvements will occur to
those skilled in the art. It is desired that it be understood,
therefore, that the invention is not limited to the particular form
shown and it is intended in the appended claims which follow to
cover all modifications which do not depart from the spirit and
scope of the invention.
* * * * *