U.S. patent application number 12/340893 was filed with the patent office on 2009-06-25 for solvent compositions.
This patent application is currently assigned to SOLVAY S.A.. Invention is credited to Pierre Dournel.
Application Number | 20090159850 12/340893 |
Document ID | / |
Family ID | 8856337 |
Filed Date | 2009-06-25 |
United States Patent
Application |
20090159850 |
Kind Code |
A1 |
Dournel; Pierre |
June 25, 2009 |
Solvent Compositions
Abstract
Composition comprising at least one hydrofluoroalkane and at
least one fluoropolyether.
Inventors: |
Dournel; Pierre; (Brussels,
BE) |
Correspondence
Address: |
CONNOLLY BOVE LODGE & HUTZ, LLP
P O BOX 2207
WILMINGTON
DE
19899
US
|
Assignee: |
SOLVAY S.A.
Brussels
BE
|
Family ID: |
8856337 |
Appl. No.: |
12/340893 |
Filed: |
December 22, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10416062 |
May 7, 2003 |
7468142 |
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PCT/EP01/12988 |
Nov 7, 2001 |
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12340893 |
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Current U.S.
Class: |
252/364 |
Current CPC
Class: |
C08G 65/007 20130101;
C11D 7/505 20130101; C11D 7/5018 20130101; C09K 2205/22 20130101;
C09K 2205/112 20130101; C08L 71/02 20130101; C08J 2203/12 20130101;
C09D 7/20 20180101; C23G 5/02803 20130101; C09K 5/045 20130101;
C08J 9/149 20130101; C08J 2203/142 20130101; C08J 2203/146
20130101 |
Class at
Publication: |
252/364 |
International
Class: |
C09K 3/00 20060101
C09K003/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 8, 2000 |
FR |
00/14514 |
Claims
1. A composition comprising at least one hydrofluoroalkane having a
boiling point greater than or equal to 10.degree. C. at 101.3 kPa,
at least one perfluoropolyether.
2. Composition according to claim 1, in which the
perfluoropolyether has a boiling point less than or equal to
200.degree. C. at 101.3 kPa.
3-24. (canceled)
Description
[0001] The present invention relates to solvent compositions and
their use.
[0002] International agreements aiming to protect the stratospheric
ozone layer require the reduction or even gradual elimination of
the use of chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons
(HCFCs). Compounds of this kind are used inter alia as solvents or
as refrigerants. For example, CFC-11 (CFC-113) is used as a
degreasing solvent or for cleaning surfaces. More recently,
HCFC-141b has been used for these applications. The latter compound
is also used with surfactants in drying agents. CFC-11 (CFC-11) and
HCFC-123 are used, for example, as refrigerants in
turbocompressors.
[0003] Patent Application JP-A-08/020,553 proposes compositions
containing an flammable organic compound, a perfluoropolyether and
a fluorocarbon such as, in particular, HCFC-141b, these possibly
being used as a solvent and as a dispersion agent. These mixtures
have a certain flammability.
[0004] It was desirable to find non-flammable compositions free of
products capable of impairing the stratospheric ozone layer,
possibly having advantages as regards their liquid-vapour
equilibrium, namely in particular a substantially constant vapour
pressure when they are subjected to an evaporation operation. It
was also desirable to find compositions suitable for use in
processes for manufacturing polymer layers.
[0005] The invention therefore relates to a composition comprising
at least one, hydrofluoroalkane having a boiling point greater than
or equal to 10.degree. C. at 101.3 kPa and at least one
perfluoropolyether.
[0006] It has been found that the composition according to the
invention has advantages as regards its liquid-vapour equilibrium
while being non-flammable. It has been found that the composition
according to the invention can be used advantageously for
suspending, dispersing or dissolving materials intended to be
deposited in layer form on a surface, particularly
fluoropolymers.
[0007] For the purposes of the present invention the term
"hydrofluoroalkane" is understood to mean a saturated organic
compound consisting only of carbon atoms, hydrogen atoms and
fluorine atoms. The hydrofluoroalkanes that can be used in the
compositions according to the invention may be linear, branched or
cyclic and contain, in general, 3, 4, 5, 6, 7, 8, 9 or 10 carbon
atoms.
[0008] The F/H numerical ratio (the number of fluorine atoms in the
molecule divided by the number of hydrogen atoms in the molecule)
of the hydrofluoroalkane is generally greater than or equal to 0.5.
An F/H numerical ratio greater than or equal to 0.6 is very
suitable. Preferably, the F/H numerical ratio is greater than or
equal to 1. The F/H numerical ratio is generally less than or equal
to 20. Preferably the F/H numerical ratio is less than or equal to
4.
[0009] In the compositions according to the invention, the
hydrofluoroalkane has a boiling point greater than or equal to
about 10.degree. C. at 101.3 kPa. Good results are obtained with a
hydrofluoroalkane having a boiling point greater than or equal to
about 15.degree. C. at 101.3 kPa. In a preferred embodiment, the
hydrofluoroalkane has a boiling point greater than or equal to
about 20.degree. C. at 101.3 kPa. The hydrofluoroalkane generally
has a boiling point less than or equal to about 200.degree. C. at
101.3 kPa. Good results are obtained with a hydrofluoroalkane
having a boiling point less than or equal to about 100.degree. C.
at 101.3 kPa.
[0010] Typical examples of hydrofluoroalkanes are chosen from
hydrofluoropropanes, hydrofluorobutanes and hydrofluoropentanes.
Specific examples of such hydrofluoroalkanes are
1,1,1,3,3-pentafluoropropane (HFC-245fa),
1,1,1,3,3-pentafluorobutane (HFC-365mfc) and
1,1,1,2,3,4,4,5,5,5-decafluoropentane (HFC-43-10mee).
1,1,1,3,3-pentafluoropropane and 1,1,1,3,3-pentafluorobutane are
preferred. 1,1,1,3,3-pentafluorobutane is most particularly
preferred.
[0011] For the purposes of the present invention, the term
"perfluoropolyether" is intended to mean a compound consisting
essentially of carbon, fluorine and oxygen atoms and comprising at
least 2, preferably at least 3, C--O--C ether linkages or a mixture
of several compounds satisfying this definition. Often the oxygen
atoms in the perfluoropolyether are exclusively present within the
C--O--C ether linkages.
[0012] In the compositions according to the invention, the
perfluoropolyether generally has a boiling point greater than or
equal to about 40.degree. C. at 101.3 kPa. Good results are
obtained with a perfluoropolyether having a boiling point greater
than or equal to about 45.degree. C. at 101.3 kPa. The
perfluoropolyether generally has a boiling-point less than or equal
to about 200.degree. C. at 101.3 kPa. Good results are obtained
with a perfluoropolyether having a boiling point less than or equal
to about 150.degree. C. at 101.3 kPa.
[0013] In the compositions according to the invention, the
perfluoropolyether generally has a molecular mass greater than or
equal to about 200. When the perfluoropolyether is a mixture of
several compounds, the molecular mass is die weight-average
molecular mass ( M.sub.w). Good results are obtained with a
perfluoropolyether having a molecular mass greater than or equal to
about 250. The perfluoropolyether generally has a molecular mass
less than or equal to about 2000. Good results are obtained with a
perfluoropolyether having a molecular mass less than or equal to
about 1500.
[0014] When the perfluoropolyether is a mixture of compounds, it is
preferred to have a mixture whose boiling point is substantially
homogeneous. A mixture of this type may consist, for example, of a
distillation fraction having a boiling range less than or equal to
8.degree. C., more often less than or equal to 5.degree. C. and
preferably less than or equal to 2.degree. C. In this case, the
boiling point of the perfluoropolyether indicated above is the
arithmetic mean of the two extreme temperatures of the boiling
range.
[0015] In a particular embodiment, the kinematic viscosity of the
perfluoropolyether is less than or equal to 1 cSt (Centistoke) at
25.degree. C. Often the kinematic viscosity of the
perfluoropolyether is less than or equal to 0.9 cSt at 25.degree.
C. Preferably, the kinematic viscosity of the perfluoropolyether is
less than or equal to 0.8 cSt at 25.degree. C. A perfluoropolyether
having a kinematic viscosity of less than or equal to 0.6 cSt at
25.degree. C. is more particularly preferred. In the particular
embodiment, the kinematic viscosity of the perfluoropolyether is
generally at least 0.3 cSt (Centistoke) at 25.degree. C.
[0016] Perfluoropolyethers that can be used in the compositions
according to the invention are commercially available or can be
obtained by known processes (see, for example, Ameduri and
Boutevin, Top. Curr. Chem. (1997), Vol. 192, p. 178-179). The
perfluoropolyether can be obtained, for example, by a process
comprising: [0017] (a) the photooxidation of a fluoroolefin
preferably chosen from hexafluoropropylene and tetrafluoroethylene;
[0018] (b) a chemical and/or physical treatment of the
photooxidation product, [0019] (c) a distillation in order to
isolate the desired perfluoropolyether.
[0020] The chemical treatment may, for example, be a fluorination.
The physical treatment may, for example, be a photolysis or a
thermolysis. Perfluoropolyethers that can be used are, for example,
those satisfying, the general formulae
CF.sub.3--[(OCF(CF.sub.3)--CF.sub.2).sub.a--(O--CF.sub.2).sub.b]O--CF.sub-
.3 (I) and
CF.sub.3--[(OCF.sub.2--CF.sub.2).sub.c--(O--CF.sub.2).sub.d]O---
CF.sub.3 (II) in which a, b, c and d independently denote integers
greater than 0.
[0021] Particular examples of perfluoropolyethers are those
marketed by Ausimont under the names GALDEN.RTM. and FOMLIN.RTM..
Mention may be made, for example, of the perfluoropolyether
GALDEN.RTM. HT 55 satisfying the general formula (I) and having a
boiling point of about 57.degree. C. at 101.3 kPa and an average
molecular mass of about 340 and the perfluoropolyether FOMBLIN.RTM.
PFS1 having a boiling point of about 90.degree. C. at 101.3 kPa and
an average molecular mass of about 460.
[0022] A further particularly suitable perfluoropolyether is the
perfluoropolyether GALDEN.RTM. HT 70 satisfying the general formula
(I) and having a boiling point of about 66.degree. C. at 101.3
kPa.
[0023] When the compositions according to the invention are
subjected to an evaporation operation, their vapour pressure is
substantially constant. In general, when the compositions according
to the invention are subjected to an evaporation operation, after
50% by weight of the composition has evaporated the vapour pressure
of the remaining composition differs from the vapour pressure of
the initial composition by less than or equal to 10%. Preferably,
this difference is less than or equal to 5%.
[0024] In an alternative embodiment it has however been found that
when some compositions according to the invention are subjected to
an evaporation operation, after 50% by weight of the composition
has evaporated, the vapour pressure of the remaining composition
differs from the vapour pressure of the initial composition by more
than 10%. In this embodiment, it is preferred that the
perfluoropolyether is contained in the liquid composition in an
effective amount to ensure that the vapour phase above said liquid
composition after 50 weight % evaporation remains
non-flammable.
[0025] In the compositions according to the invention, the weight
ratio of the hydrofluoroalkane to the perfluoropolyether is
generally greater than or equal to 5:95. Often the weight ratio is
greater than or equal to 10:90. Preferably, the ratio is greater
than or equal to 25:75. The weight ratio of the hydrofluoroalkane
to the perfluoropolyether is generally less than or equal to 95:5.
Often the weight ratio is less than or equal to 90:10. Preferably,
the ratio is less than or equal to 85:15.
[0026] Fundamentally, the thermodynamic state of a fluid is defined
by four interdependent variables, namely the pressure (P), the
temperature (T), the composition of the liquid phase (X) and the
composition of the gas phase (Y). A true azeotrope is one
particular system consisting of two or more components for which,
at a given temperature and a given pressure, the composition of the
liquid phase X is exactly the same as the composition of the gas
phase Y. A pseudo-azeotrope is a system consisting of two or more
components for which, at a given temperature and a given pressure,
X is substantially the same as Y. In practice, this means that the
constituents of such azeotropic and pseudo-azeotropic systems
cannot be easily separated by distillation and consequently the gas
phase is not enriched with the flammable compound.
[0027] For the purposes of the present invention, the term
"pseudo-azeotropic mixture" is understood to mean a mixture of two
constituents whose boiling point (at a given pressure) differs from
the boiling point of the true azeotrope by at most 0.5.degree. C.
Mixtures whose boiling point differs from the boiling point of the
true azeotrope by at most 0.2.degree. C. are preferred. Mixtures
whose boiling point differs from the boiling point of the true
azeotrope by at most 0.1.degree. C. are particularly preferred.
[0028] 1,1,1,3,3-pentafluorobutane and the perfluoropolyether
GALDEN.RTM. HT 55 form a binary azeotrope or pseudo-azeotrope when
their mixture contains about 17 to 48% by weight of the
perfluoropolyether GALDEN.RTM. HT 55. Binary compositions
containing from 23 to 42% by weight of the perfluoropolyether
GALDEN.RTM. HT 55 are preferred. Binary compositions containing
about 30 to 40% by weight of the perfluoropolyether GALDEN.RTM. HT
55 are particularly preferred. At a pressure of 100.1.+-.0.2 kPa,
the binary composition essentially consists of about 64.4% by
weight of 1,1,1,3,3-penta-fluorobutane and about 35.6% by weight of
the perfluoropolyether GALDEN.RTM. HT 55 constitutes a true
azeotrope whose boiling point is about 37.8.degree. C. The true
azeotrope is non-flammable and has no flash point determined
according to the ISO 1523 standard.
[0029] 1,1,1,3,3-pentafluorobutane and the perfluoropolyether
GALDEN.RTM. HT 70 form a binary azeotrope or pseudo-azeotrope at
atmospheric pressure (about 101.3 kPa) when their mixture contains
from 23% to 43% by weight of the perfluoropolyether GALDEN.RTM. HT
70. Binary compositions containing from 28% to 38% by weight of the
perfluoropolyether GALDEN.RTM. HT 70 are preferred. Binary
compositions containing about 31% to 35% by weight of the
perfluoropolyether GALDEN.RTM. HT 70 are particularly preferred. At
a pressure of about 101.3 kPa, the binary composition essentially
consists of about 67% by weight of 1,1,1,3,3-pentafluorobutane and
about 33% by weight of the perfluoropolyether GALDEN.RTM. HT 70
constitutes a true azeotrope whose boiling point is about
38.degree. C.
[0030] Another composition according to the invention which is
non-flammable according to the ISO 1523 standard essentially
consists of about 30% by weight of 1,1,1,3,3-pentafluorobutane and
about 70% by weight of the perfluoropolyether FOMBLIN.RTM.
PFS1.
[0031] The invention also relates to a composition comprising at
least one hydrofluoroalkane having a boiling point greater than or
equal to 10.degree. C. at 101.3 kPa and at least one
hydrofluoropolyether having a boiling point greater than or equal
to 40.degree. C. at 101.3 kPa.
[0032] The hydrofluoroalkanes having a boiling point greater than
or equal to 10.degree. C. at 101.3 kPa that can be used in these
compositions are the same as those described above within the
context of the compositions containing a perfluoropolyether.
[0033] For the purposes of the present invention, the term
"hydrofluoropolyether" is understood to mean a compound essentially
consisting of carbon, fluorine, oxygen and hydrogen atoms,
containing at least one C--H linkage and comprising at least two,
preferably three, C--O--C ether linkages, or a mixture of several
compounds satisfying this definition. Often, the oxygen atoms in
the hydrofluoropolyether are exclusively present within the C--O--C
ether linkages. In general, the hydrofluoropolyether contains a
plurality of C--H linkages. Specific examples of
hydrofluoropolyethers contain at least one --CF.sub.2H group.
Hydrofluoropolyethers that can be used are, for example, those
marketed by Ausimont under the name H-GALDEN.RTM..
Hydrofluoropolyethers that can be used may be obtained, for
example, by a process like that described above for the manufacture
of the perfluoropolyethers, preferably comprising a hydrogenation
step. The boiling point of the hydrofluoropolyethers that can be
used is greater than or equal to 40.degree. C. at 101.3 kPa. Apart
from this fact, the boiling points, boiling point range, viscosity,
molecular masses and weight ratios of hydrofluoropolyether in the
compositions according to the invention containing a
hydrofluoropolyether are the same as those described above in the
case of the compositions containing a perfluoropolyether.
[0034] Examples of suitable hydrofluoropolyethers include, amongst
others, the hydrofluoropolyether H-GALDEN.RTM. Grade A having a
boiling point at 101.3 kPa of about 56.degree. C. and the
hydrofluoropolyether H-GALDEN.RTM. Grade B having a boiling point
at 101.3 kPa of about 88.degree. C.
[0035] The invention also relates to a composition according to the
invention furthermore containing a non-fluorinated organic solvent.
As the non-fluorinated organic solvent, for example, hydrocarbons,
chlorinated hydrocarbons, alcohols, esters, ketones or ethers are
very suitable.
[0036] In a specific embodiment the composition according to the
invention furthermore contains more than one non-fluorinated
organic solvent. A composition according to the invention
furthermore containing 1, 2 or 3 non-fluorinated organic solvents
is particularly preferred.
[0037] The hydrocarbons that can be used in the compositions
according to the invention may be linear, branched or cyclic and
generally contain 3, 4, 5, 6, 7, 8, 9, 10, 11 or 12 carbon atoms.
Hydrocarbons containing at least 5 carbon atoms are very suitable.
Preferably, the hydrocarbons contain at least 6 carbon atoms. Among
alkanes or alkenes, compounds containing from 5 to 12 carbon atoms
are preferred. N-hexane or n-heptane or n-octane are very suitable.
Among aromatic hydrocarbons, those containing at least one alkyl
substituent on a benzene ring are preferred. Toluene, 1,2-xylene,
1,3-xylene; 1,4-xylene or mixtures thereof are most particularly
preferred.
[0038] In another preferred embodiment, the hydrocarbon is a
paraffinic hydrocarbon fraction which can be obtained by
petrochemical refinery of hydrocarbon feedstocks. Such fractions
are commercially available, for example from SHELL or EXXON and are
often characterised by their flash point. A paraffinic hydrocarbon
fraction, which is suitable for use in the compositions according
to the invention, has generally a flash point equal to or greater
than 40.degree. C., determined according to the standard IP 170
(Abel). Often, the flash point of the paraffinic hydrocarbon
fraction is at least 50.degree. C. A paraffinic hydrocarbon
fraction having a flash point equal to or greater than 60.degree.
C. A paraffinic hydrocarbon fraction having a flash point equal to
or greater than 70.degree. C. such as for example SHELLSOL.RTM. D70
or SHELLSOL.RTM. D90 commercialised by SHELL is more particularly
preferred.
[0039] The compositions according to the invention containing at
least a hydrocarbon, preferably a paraffinic hydrocarbon fraction
as described herebefore, are particularly suitable for degreasing
applications.
[0040] The chlorinated hydrocarbons that can be used in the
compositions according to the invention may be linear, branched or
cyclic and generally contain 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 carbon
atoms. Chlorinated hydrocarbons containing 1, 2, 3 or 4 carbon
atoms are very suitable. Preferably, the chlorinated hydrocarbons
contain 1 or 2-carbon atoms. Among chlorinated alkanes,
dichloro-methane, trichloromethane and 1,2-dichloroethane are
preferred. Among chlorinated alkenes, perchloroethylene and
1,2-dichloroethylene are preferred, trans-1,2-dichloroethylene
being most particularly preferred.
[0041] In a particular embodiment the compositions according to the
invention comprise 1,1,1,3,3-pentafluorobutane, the
perfluoropolyether GALDEN.RTM. HT 55 and trans-1,2-dichloroethylene
in proportions at which they form an azeotrope or pseudo-azeotrope.
1,1,1,3,3-pentafluorobutane, the perfluoropolyether GALDEN.RTM. HT
55 and trans-1,2-dichloroethylene form a ternary azeotrope or
pseudo-azeotrope at a pressure of about 101.3 kPa when their
mixture contains about from 13 to 53% 1,1,1,3,3-pentafluorobutane,
from 31 to 51% by weight of the perfluoropolyether GALDEN.RTM. HT
55 and from 16 to 36% by weight of trans-1,2-dichloroethylene.
Ternary compositions containing from 23 to 43%
1,1,1,3,3-pentafluorobutane, from 36 to 46% by weight of the
perfluoropolyether GALDEN.RTM. HT 55 and from 21 to 31% by weight
of trans-1,2-dichloroethylene are preferred. Ternary compositions
containing from 29 to 37% 1,1,1,3,3-pentafluorobutane, from 39 to
43% by weight of the perfluoropolyether GALDEN.RTM. HT 55 and from
24 to 28% by weight of trans-1,2-dichloroethylene are particularly
preferred. At a pressure of about 101.3 kPa, the ternary
composition essentially consists of about 33% by weight of
1,1,1,3,3-pentafluorobutane, 41% by weight of the
perfluoropolyether GALDEN.RTM. HT 55 and about 26% by weight of
trans-1,2-dichloroethylene which constitutes a true azeotrope whose
boiling point is about 32.degree. C.
[0042] The alcohols that can be used in the compositions according
to the invention may be linear, branched or cyclic and generally
contain 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 carbon atoms. Alcohols
containing 1, 2, 3, 4 or 5 carbon atoms are very suitable.
Preferably, the alcohols contain 1, 2, 3 or 4 carbon atoms. Among
alkanols, methanol, ethanol, n-propanol, isopropanol n-butanol
isobutanol and tert-butanol are preferred. Methanol, ethanol,
isopropanol and isobutanol give good results. Methanol and ethanol
are most particularly preferred.
[0043] In a particular embodiment, the composition according to the
invention comprises a butanol, in particular isobutanol.
Compositions comprising a butanol are suitably used when
incorporation of a surfactant into the composition according to the
invention is desired.
[0044] The esters that can be used in the compositions according to
the invention may be linear, branched or cyclic and generally
contain 2, 3, 4, 5, 6, 7, 8, 9 of 10 carbon atoms. Esters
containing 4, 5, 6, 7, 8 or 9 carbon atoms are very suitable.
Preferably the esters are derived from a carboxylic acid containing
at least 2 carbon atoms. Preferably, the esters are derived from an
alkanol selected from the group consisting of methanol, ethanol,
n-propanol, isopropanol, n-butanol, isobutanol and tert-butanol.
Ethyl acetate, ethyl butyrate and ethyl caproate are very
suitable.
[0045] The ketones that can be used in the compositions according
to the invention may be linear, branched or cyclic and generally
contain 3, 4, 5, 6, 7, 8, 9 or 10 carbon atoms. Ketones containing
3, 4, 5, 6, 7 or 8 carbon atoms are very suitable. Among ketones,
acetone, 2-butanone, 2-pentanone, 3-pentanone, methyl isobutyl
ketone, diisopropyl ketone, cyclohexanone and acetophenone are
preferred. Methyl isobutyl-ketone is particularly preferred.
[0046] The ethers that can be used in the compositions according to
the invention may be linear, branched or cyclic and generally
contain 2, 3, 4, 5, 6, 7, 8, 9 or 10 carbon atoms. Ethers
containing 4, 5, 6, 7, 8 or 9 carbon atoms are very suitable. Among
aliphatic or alicyclic ethers, diethyl ether, methyl isopropyl
ether, diethylene glycol monomethyl ether, diethylene glycol
dimethyl ether, tetrahydrofuran ad 1,4-dioxane are preferred.
[0047] The non-fluorinated organic solvent content in a composition
according to the invention may be chosen according to the desired
polarity and the desired flammability of the composition. In
general, this content is at most 50% by weight. Often it is at most
20% by weight. Preferably, it is at most 10% by weight. When a
non-fluorinated organic solvent is present, its content is
generally at least 1% by weight. It is preferably at least 2% by
weight.
[0048] Among the compositions according to the invention
furthermore containing at least a non-fluorinated organic solvent,
those which comprise 1,1,1,3,3-pentafluorobutane and a
perfluoropolyether in proportions at which they form an azeotrope
or pseudo-azeotrope, such as compositions of
1,1,1,3,3-pentafluorobutane with GALDEN.RTM. HT 55
perfluoropolyether and/or GALDEN.RTM. HT 70 perfluoropolyether such
as described above are particularly preferred. In fact, in this
preferred embodiment, the composition of the vapour phase above a
liquid composition according to the invention is generally close to
the azeotrope of 1,1,1,3,3-pentafluorobutane with the
perfluoropolyether, so that the vapour phase remains non-flammable
also when a flammable non-fluorinated organic solvent is used.
[0049] In another aspect, the compositions according to the
invention additionally contain an aqueous phase. A aqueous phase
consisting essentially of water is preferred. It has been found
that, surprisingly, the compositions according to the invention
additionally containing an aqueous phase form a stable emulsion
which does not break even after a long period of storage. Often, if
a stable emulsion is desired, the composition comprises in addition
a surfactant. In a preferred embodiment, the composition
comprises
(a) a hydrofluoroalcane, (b) a perfluoropolyether or a
hydrofluoropolyether, (c) at least one non fluorinated organic
solvent, (d) a surfactant and (e) water.
[0050] A hydrocarbon and/or an alcanol, as described above, are
preferred as the non-fluorinated organic solvent in this
embodiment.
[0051] The compositions according to the invention are very
suitable for applications as refrigerants, as heat-transfer fluids,
as blowing agents for polymeric foams, as toner fixing agents, as
dying solvents and as degreasing solvents.
[0052] The compositions according to the invention comprising at
least one non-fluorinated organic solvent are particularly suitable
for applications as drying or degreasing solvents.
[0053] A drying solvent is used, for example, in the electronic,
electromechanical or possibly cosmetic industries when it is
desired to remove water adsorbed on a solid surface of an article
after an aqueous treatment. The aqueous treatment may consist, for
example, of a cleaning operation possibly in the presence of a
surfactant. A few surfactants that can be used in the compositions
according to the invention are described, for example, in Ullmann's
Encyclopedia of Industrial Chemistry, 5th edition, 1987, Vol. A8,
pp. 338-350. Cationic, anionic, nonionic and amphoteric surfactants
may be used. In general, after the aqueous treatment the article is
immersed in a drying solvent in the boiling state comprising a
surfactant, and then the surfactant adhering to the surface of the
article is removed in a washing bath. The compositions according to
the invention which furthermore contain a surfactant as described
above are very suitable for the drying operation. The compositions
according to the invention containing no surfactant are very
suitable for the washing bath intended to remove the
surfactant.
[0054] A degreasing solvent is used, for example in the electronic
or electromechanical industry, to remove grease adsorbed in
particular on metal parts machined using grease. In general, a part
to be degreased is immersed in a, degreasing solvent bath in the
boiling state. Particularly suitable as degreasing solvents are
compositions according to the invention comprising a highly polar
non-fluorinated organic solvent, such as alkanols, in particular
methanol, ethanol or isobutanol and/or those which comprise a
chlorinated hydrocarbon.
[0055] A toner fixing agent is used to fix toner particles to a
medium. Toner particles generally comprise a polymer and a pigment.
During electrophotographic printing, the particles are attracted to
the electrostatic image printed on the medium by electrostatic
forces. The toner fixing agent serves to soften the polymer, which
consequently ensures permanent adhesion of the particles to the
medium. Toner fixing agents are used in vapour form the vapour
generally being generated by drops of solvent vaporizing on, for
example, a hot plate. The non-flammable compositions according to
the intention having a high polymer solvent power are very suitable
for this application.
[0056] The compositions according to the invention which are
non-flammable according to the ISO 1523 standard may be
advantageously used as a drying solvent in a drying machine or as a
toner fixing agent in an industrial laser printer.
[0057] The compositions according to the invention are also very
suitable as refrigerants, in particular as products to replace,
CFC-11 (trichlorofluoromethane) or as products to replace CFC-113
(1,1,2-trichlorotrifluoroethane), especially for applications with
a turbocompressor. Turbocompressors are used most especially when
it is desired to obtain high levels of refrigeration for
air-conditioning plants for example or for the process industry.
Information regarding refrigeration applications, heat-transfer
fluids and refrigeration using a turbocompressor are contained) for
example, in Ullmann's Encyclopedia of Industrial Chemistry, 5th
edition, 1988, Vol. B3, pp. 19-2 to 19-39. Particularly suitable
for this application are azeotropic or pseudo-azeotropic
compositions essentially consisting of 1,1,1,3,3-pentafluorobutane
and the perfluoropolyether GALDEN.RTM. HT 55.
[0058] The invention also relates to the use of the compositions
according to the invention as a blowing agent, in particular for
polymeric foams. The compositions according to the invention are
very suitable for the manufacture of polyurethane foams. The
invention consequently also relates to a process for manufacturing,
polyurethane or modified polyurethane (polyisocyanurate) foams in
which at least one isocyanate is made to react with at least one
polyol in the presence of a composition according to the invention,
at least one catalyst and other standard additives. Particularly
suitable for this application are the compositions according to the
invention comprising 1,1,1,3,3-pentafluorobutane and a
hydrofluoropolyether.
[0059] The compositions according to the invention are also
suitable for the manufacture of phenolic resins. Particularly
suitable for this application are the compositions according to the
invention comprising 1,1,1,3,3-pentafluorobutane and a
hydrofluoropolyether.
[0060] The invention also relates to the use of a hydrofluoroalkane
having a boiling point greater than or equal to 10.degree. C. at
101.3 kPa for the manufacture of a coating composition intended to
deposit a layer of material on a body.
[0061] It has been found that the hydrofluoroalkanes having a
boiling point greater than or equal to 10.degree. C. at 101.3 kPa,
in particular 1,1,1,3,3-pentafluorobutane are a suitable
constituent of compositions that can be used for dissolving,
dispersing or suspending inorganic or organic materials intended
for deposition on a surface, in the form of a layer.
[0062] The invention therefore also relates to a coating
composition comprising a hydrofluoroalkane-having a boiling point
greater than or equal to 10.degree. C. at 101.3 kPa and at least
one material suitable to be deposited in layer form on a
surface.
[0063] Examples of materials able to be contained in a coating
composition according to the invention are chosen inter alia, from
adhesives, colorants, inorganic compounds, lubricants, pigments,
stabilizers, possibly pharmaceutical products, etc.
[0064] The coating composition may contain, for example, as
material, a polymer. Polymers that can be used in the coating
composition according to the invention may be chosen from, for
example, fluoropolymers and acrylic polymers.
Polytetrafluoroethylene (PTFE) is very suitable.
[0065] The coating compositions according to the invention
containing a fluoropolymer are preferred. Specific examples of
fluoropolymers are fluoropolymers which can be used as greases or
lubricants. The coating compositions according to the invention are
particularly useful to deposit a fluorinated grease onto a solid
surface. Use of a coating composition comprising an azeotropic or
pseudo-azeotropic composition according to the invention as
described above and a fluoropolymer as described herebefore is
particularly preferred.
[0066] In a further embodiment, the coating composition according
to the invention contains a silicone. The term silicone is
understood to denote a siloxane polymer. A polyalkylsiloxane
polymer is particularly suited.
[0067] The coating composition may also contain, as material, a
metal salt or a metal complex. Metal oxides such as titanium oxide,
magnesium oxide and iron oxide are very suitable.
[0068] Preferably, the coating composition according to the
invention comprises a composition containing a hydrofluoroalkane
and a perfluoropolyether or a hydrofluoropolyether as described
above.
[0069] The content of material suitable to be deposited in layer
form on a surface in the coating composition according to the
invention is generally greater than or equal to 0.01% by weight.
Often this content is greater than or equal to 0.1% by weight.
Preferably, this content is greater than or equal to 0.2% by
weight. The content of material suitable to be deposited in layer
form on a surface in the coating composition according to the
invention is generally less than or equal to 20% by weight. Often
his content is less than or equal to 10% by weight. Preferably,
this content is less than or equal to 5% by weight.
[0070] In a first aspect, the coating composition according to the
invention is in the form of a suspension.
[0071] In a second aspect, the coating composition according to the
invention is in the form of a dispersion.
[0072] In a third aspect, the coating composition according to the
invention is in the form of a solution.
[0073] The invention also relates to a process for manufacturing a
body comprising at least one surface on which a layer of material
is deposited, in which process: [0074] (a) the surface is brought
into contact with the coating composition according to the
invention; and [0075] (b) the surface is subjected to a treatment
allowing at least the hydrofluoroalkane to evaporate.
[0076] The treatment allowing at least the hydrofluoroalkane to
evaporate may, for example, be a heat treatment or a pressure
reduction.
[0077] In another embodiment, when the coating compositions
comprises a composition according to the invention containing a
hydrofluoroalkane and a perfluoropolyether or a
hydrofluoropolyether, the surface is suitably subjected to a
treatment allowing for evaporation at least of the composition
according to the invention.
[0078] The example below is meant to illustrate the invention
without, however, limiting it.
EXAMPLE 1
HFC-365mfc/GALDEN.RTM. HT 55 Perfluoro-Polyether Azeotrope
[0079] To demonstrate the existence of azeotropic or
pseudo-azeotropic compositions according to the invention
containing 1,1,1,3,3-pentafluorobutane and the GALDEN.RTM. HT 55
perfluoropolyether, a glass apparatus consisting of a 50 ml boiling
flask surmounted by a reflux condenser was used. The temperate of
the liquid was measured by means of a thermometer immersed in the
flask.
[0080] A precisely defined amount of pure
1,1,1,3,3-pentafluorobutane was heated at a known pressure until
boiling and then accurately-weighed small amounts of GALDEN.RTM.5
HT 55 perfluoropolyether were gradually introduced into the flask
by means of a syringe via a side nozzle.
[0081] The pseudo-azeotropic compositions were determined by
measuring the variation in boiling point of the mixture as a
function of its composition.
[0082] These measurements were carried out for mixtures containing
1,1,1,3,3-pentafluorobutane and increasing amounts of GALDEN.RTM.
HT 55 perfluoropolyether at a pressure of 100.1.+-.0.2 kPa.
[0083] The variation in the boiling point of the various
compositions as a function of their HFC-365mfc and
perfluoropolyether contents, expressed in % by weight, is shown in
Table 1.
TABLE-US-00001 TABLE 1 HFC-365mfc GALDEN .RTM. HT 55 Temperature
(wt %) Perfluoropolyether (wt %) (.degree. C.) 100.00% 0.00% 40.8
99.36% 0.64% 40.7 98.64% 1.36% 40.5 97.69% 2.31% 40.3 96.34% 3.66%
40 94.99% 5.01% 39.7 93.27% 6.73% 39.4 91.68% 8.32% 39.2 89.23%
10.77% 38.9 86.76% 13.24% 38.6 84.08% 15.92% 38.4 80.80% 19.20%
38.2 77.32% 22.68% 38 74.05% 25.95% 37.9 70.01% 29.99% 37.8 64.38%
35.62% 37.8 59.59% 40.41% 37.8 54.96% 45.04% 38.2 50.65% 49.35%
38.4 45.56% 54.44% 39.1
[0084] The azeotropic composition did not exhibit a flash point
determined according to the ISO 1523 standard.
EXAMPLE 2
HFC-365mfc/GALDEN.RTM. HT 70 Perfluoropolyether Azeotrope
[0085] 194 g of a mixture consisting 68% by weight of HFC-365mfc
and 32% wt. of GALDEN.RTM. HT70 perfluoropolyether was distilled
under atmospheric pressure (about 101.3 kPa) over a 10 cm
Vigreux-column. A fraction corresponding to 11% wt. of the initial
composition, having a boiling point of 38.degree. C. was recovered
from the distillation and its composition was analysed by gas
chromatography. It was found that this fraction which consisted of
67% by weight of HFC-365mfc and 33 wt. of GALDEN.RTM. HT70
perfluoropolyether is a true minimum boiling point azeotrope. The
vapours present above the recovered fraction could not be ignited
by a bug match.
[0086] The flammability of a pseudo-azeotropic composition
consisting of 77% by weight of HFC-365mfc and 23% wt. of
GALDEN.RTM. HT70 perfluoropolyether was examined. The vapours
present above the composition could not be ignited by a burning
match.
EXAMPLE 3
Ternary Azeotrope of HFC-365mfc/GALDEN.RTM. HT55
Perfluoropolyether/Trans-1,2-dichloroethylene
[0087] 194 g of a mixture consisting of one third by weight of each
of HFC-365mfc, GALDEN.RTM. HT55 perfluoropolyether and
trans-1,2-dichloroethylene was distilled under atmospheric pressure
(about 101.3 kPa) over a 10 cm Vigreux-column. A first fraction
corresponding to 19% wt. of the initial composition, having a
boiling point of 32.degree. C. was recovered from the distillation
and its composition was analysed by gas chromatography. The content
of BC-365mfc, GALDEN.RTM. HT55 perfluoropolyether and
trans-1,2-dichloroethylene was 33% wt., 41 wt % and 26 wt %
respectively. A further fraction corresponding to 17% wt. of the
initial composition, having a boiling point of 32.degree. C. was
recovered after 59% of the initial composition had been distilled.
The content of HFC-365mfc, GALDEN.RTM. HT55 perfluoropolyether and
trans-1,2-dichloroethylene was 34% wt., 40 wt % and 26 wt %
respectively. The recovered fractions were found to be a true
minimum boiling point azeotrope. The vapours present above the
recovered fractions could not be ignited by a burning match.
EXAMPLE 4
Emulsion
[0088] A composition according to, the invention comprising the
azeotrope of HFC-365mfc and GALDEN.RTM. HT 55 perfluoropolyether
was prepared. To this effect 20 g of an azeotropic composition of
65 wt % HFC-365mfc and 35 wt % GALDEN.RTM. HT55 were mixed with 5 g
of SHELLSOL.RTM. D70 paraffinic hydrocarbon mixture (commercialised
by Shell), 3 g of isobutanol and 5000 ppm wt. of NANSA.RTM. YS94
surfactant (commercialised by Rhodia). Finally 5 g of water was
added and the mixture was agitated. A stable emulsion of water in
the organic solvents was formed which did not break when stored for
several weeks at room temperature. The vapours present above the
recovered fractions could not be ignited by a burning match. The
emulsion is useful for degreasing applications, especially for
cold-degreasing optionally with ultrasound.
EXAMPLE 5
Degreasing Composition
[0089] A composition according to, the invention comprising the
azeotrope of HFC-365mfc and GALDEN.RTM. HT 55 perfluoropolyether
was prepared. To this effect 140 g of an azeotropic composition of
65 wt % HFC-365mfc and 35 wt % GALDEN.RTM. HT55 were mixed with 60
g of SHELLSOL.RTM. D70 paraffinic hydrocarbon mixture
(commercialised by Shell). This blend gave a fine dispersion of
hydrocarbon in the fluorinated compounds at the boiling point of
the composition. A rectangular 2.times.10 cm carbon steel part
covered with a film of 1 g of a standard grease used for metal
cutting was immersed into the above composition at the boiling
temperature of the composition under atmospheric pressure. The
evolution of the degreasing process was followed by monitoring each
minute. After 4 minutes more than 95% of the grease was removed.
After 5 minutes 100% of the grease was removed.
EXAMPLE 6
Coating Composition
[0090] In a solvent composition according to the invention
consisting of 36.5 wt. % HFC-365mfc, 24.0 wt % GALDEN.RTM. HT55
perfluoropolyether, 30.5 wt. % trans 1,2-dichloroethylene and 9 wt.
% of ethanol, 1.5 wt % of MDX4-4159 silicone (dispersion 50%
wt.)(commercialised by DOW CORNING) was dissolved. The composition
was homogeneous and did not display any flash point determined
according to standard ISO 1523. This composition can be used to
deposit a layer of silicon material onto a solid surface.
* * * * *