TECHNICAL FIELD
[0001] The present invention relates to a solvent composition used for
dissolving and diluting silicone compounds.
BACKGROUND OF THE INVENTION
[0002] Hitherto, as a solvent for diluting silicone compounds,
hydrochlorofluorocarbons (HCFCs) such as dichloropentafluoropropane
(R225), 1,1-dichloro-l-fluoroethane (R141b), etc. have widely been used,
since they are nonflammable and superior in chemical and thermal
stabilities. Since there is also a reason that HCFCs contain chlorine,
they are high in ozone depletion potential (ODP), causing concern about
the effect on the global environment. Therefore, they are scheduled to be
totally abolished in the future.
[0003] In recent years, as one of solvents alternative to HCFCs, the use
and the development of hydrofluorocarbons (HFCs) and
hydrofluoroethers (HFEs) have been in progress. HFCs and HFEs have
advantages that they are nonflammable, that they are superior in
chemical and thermal stabilities and drying characteristics, that they
have no ozone depletion potential, etc.
[0004] HFCs and HFEs are, however, not sufficient in silicone
compound solubility. Therefore, hitherto, a method of adding various
organic solvents has been studied in order to improve silicone compound
solubility.
[0005] For example, in order to improve compatibility between HFEs
and silicone compounds, there are disclosed a method of adding 4-30

mass % of hexamethyldisiloxane (Patent Publication 1) and a method of
adding 15-60 mass % of hydrocarbons, such as normal hexane, etc., and
alcohols (Patent Publication 2).
PRIOR ART PUBLICATIONS
PATENT PUBLICATIONS
[0006] Patent Publication 1: Japanese Patent Application Publication
2006-274173
Patent Publication 2: Japanese Patent Application Publication
2007-332301
SUMMARY OF THE INVENTION
[0007] In the case of coating various articles, such as metal, resin, etc.,
with a silicone compound, one prepared by adjusting concentration of the
silicone compound in the solvent to a predetermined concentration is used,
and it is necessary to adjust concentration of the silicone compound for
each of the various articles.
[0008] In the method described in Patent Publication 1, solubility of the
silicone compound becomes small as the content of hexamethyldisiloxane
to be added becomes low. As the content of hexamethyldisiloxane
becomes high, viscosity of the solvent composition becomes high, thereby
making applicability of the silicone compound inferior, lowering flash
point, etc. Therefore, handling is not easy.
[0009] Similarly, also in the method described in Patent Publication 2, if
the content of hydrocarbons or alcohols to be added becomes high,
handling is difficult in terms of problem of flash point, and it becomes

necessary to take a measure for a safe handling. For example, in the
method described in Patent Publication 2, it is necessary to add 15-60
mass % of hexane, thereby causing concern of problem of flammability.
[0010] Thus, HFEs are studied as a solvent for silicone compounds,
which is less in adverse effect on the environment, but compatibility
between HFEs and silicone compounds is not sufficient. Therefore, it is
necessary to add various organic solvents depending on the purpose of use
(for example, adjusting the silicone compound concentration to be used,
etc.). By that, there has been a problem of being not easy in handling in
terms of safety viewpoint, such as the worsening of applicability of
silicone compounds, flammability, etc.
[0011] Furthermore, if a solvent for dissolving silicone compounds is too
low in boiling point, the solvent evaporates easily, from applicability,
drying characteristics, etc. upon applying silicone compounds. Therefore,
the application is difficult. On the other hand, if it is too high in boiling
point, it is necessary to have a heating at high temperature in order to
evaporate the solvent. This may cause articles, on which silicone
compounds are applied, to have deformations and damages. Therefore,
there is a demand for a solvent of silicone compounds, which has a boiling
point close to ordinary temperature as close as possible and is easy in
handling.
[0012] The present invention was made in view of the above-mentioned
problems. Its task is to provide a solvent composition for silicone
compounds, which is good in coating properties of silicone compounds,

which has characteristics of nonflammability and low toxicity, and which
is extremely easy in handling.
[0013] As a result of a repeated eager study to solve the task, the
present inventors have solved the task by using
l-chloro-3,3,3-trifluoropropene, which is a fluorine-containing
unsaturated hydrocarbon, as a solvent for silicone compounds.
[0014] Hitherto, there has been no report of using
l-chloro-3,3,3-trifluoropropene as a solvent for silicone compounds.
[0015] That is, the present invention provides the inventions described
in [Invention l] to [Invention 9].
[0016] [Invention l] A solvent composition for silicone compounds,
comprising l-chloro-3,3,3-trifluoropropene.
[0017] [Invention 2] A solvent composition for silicone compounds,
comprising (A) l-chloro-3,3,3-trifluoropropene and (B) a compound made
up of at least one selected from the group consisting of
1,1,2,2-tetrafluoro-l-methoxyethane, 1,1,1,3,3-pentafluorobutane, and
l,l,2,2-tetrafluoro-l-(2,2,2-trifluoroethoxy)ethane.
[0018] [Invention 3] A solvent composition for silicone compounds
according to Invention 2, comprising 40-80 mass % of the
l-chloro-3,3,3-trifluoropropene and 60-20 mass % of the
1,1,2,2-tetrafluoro-l-methoxyethane.
[0019] [Invention 4] A solvent composition for silicone compounds
according to Invention 2, comprising 60-80 mass % of the

l-chloro-3,3,3-trifluoropropene and 40-20 mass % of the
1,1,1,3,3-pentafluorobutane.
[0020] [Invention 5] A solvent composition for silicone compounds
according to Invention 2, comprising 70-80 mass % of the
l-chloro-3,3,3-trifluoropropene and 30-20 mass % of the
l,l,2,2-tetrafluoro-l-(2,2,2-trifluoroethoxy)ethane.
[0021] [Invention 6] A silicone compound coating solution, comprising
a silicone compound and a solvent composition for silicone compounds
according to any one of Invention 1 to Invention 5.
[0022] [Invention 7] A silicone compound coating solution according to
Invention 6, which is characterized by that the silicone compound is a
straight silicone.
[0023] [Invention 8] A method for applying a silicone compound, which
is characterized by that the silicone compound coating solution according
to Invention 6 or Invention 7 is applied on a surface of an article, and then
the solvent composition for silicone compounds in the coating solution is
removed by evaporation, thereby forming a film of the silicone compound
on the surface of the article.
[0024] [Invention 9] A method for applying a silicone compound
according to Invention 8, which is characterized by that the article is
metal or resin.
DETAILED DESCRIPTION
[0025] A solvent composition of the present invention is high in silicone
compound solubility and superior in drying characteristics and uses

l-chloro-3,3,3-trifluoropropene, which has characteristics of
nonflammability and low toxicity, as a solvent for silicone compounds.
Therefore, it becomes possible to provide a solvent composition for silicone
compounds, which has good coating properties of silicone compounds, and
characteristics of nonflammability and low toxicity, and of which
handling is extremely easy, without adding an organic solvent causing
concern of problem of flammability, etc.
[0026] Furthermore, both cis form (Z configuration) and trans form (E
configuration) of l-chloro-3,3,3-trifluoropropene have boiling points close
to ordinary temperature. Therefore, a solvent composition of the present
invention has characteristics that it dissolves silicone compounds and
that handling when applying a silicone compound and drying it is very
easy.
[0027] Furthermore, l-chloro-3,3,3_trifluoropropene has characteristics
that ozone depletion potential (ODP) and global warming potential (GWP)
are extremely small. Therefore, a solvent composition of the present
invention has characteristics that global warming potential is small and
greenhouse effect is small.
[0028]
A solvent composition for silicone compounds of the present
invention is one containing l-chloro-3,3,3-trifluoropropene.
[0029] In the following, the present invention is explained in detail.
[0030] (l-chloro-3,3,3-trifluoropropene)

Since l-chloro-3,3,3-trifluoropropene, which is one of
fluorine-containing unsaturated hydrocarbons, has a double bond, it has a
high reactivity with OH radical in the atmosphere. Therefore, ozone
depletion potential (ODP) and global warming potential (GWP) become
extremely small. Furthermore, l-chloro-3,3,3-trifluoropropene is
nonflammable, and it is a composition having characteristics of
nonflammability and low GWP.
[0031] l-chloro-3,3,3-trifluoropropene, which is used in the present
invention, is a publicly-known compound mentioned in publications. For
example, it can be produced by a reaction of adding hydrogen chloride to
3,3,3-trifluoropropyne, or by a dehydroiodination reaction of
3-chloro-l,l,l-trifluoro-3-iodopropane by potassium hydroxide.
[0032] Furthermore, l-chloro-3,3,3-trifluoropropene, which is used in
the present invention, can also be obtained by subjecting
1,1,1,3,3-pentachloropropane to a gas phase fluorination reaction by
chromium catalyst or to a liquid phase fluorination reaction with no
catalyst.
[0033] In l-chloro-3,3,3-trifluoropropene, there exist cis form (Z
configuration) and trans form (E configuration) as stereoisomers
depending on the substituent type. Both isomers can be separated and
purified by distillation. Boiling point of cis form (Z configuration) is
39.0°C, and boiling point of trans form (E configuration) is 21.0°C.

[0034] Furthermore, these stereoisomers are not particularly limited.
It is possible to use either trans form (E configuration) or cis form (Z
configuration) or a mixture.
[0035] (Other solvent compositions)
In the present invention, it is possible to use
l-chloro-3,3,3-trifluoropropene alone as a solvent for dissolving silicone
compounds, but it is also possible to add other solvents to
l-chloro-3,3,3-trifluropropene, depending on the use.
[0036] l-chloro-3,3,3-trifluoropropene by itself, which is used in the
present invention, is very high in dissolution capacity and therefore is a
preferable solvent. In the case of using l-chloro-3,3,3-trifluoropropene
alone, it may cause damages on resin members. Therefore, for the
purpose of adjusting dissolution capacity, depending on the types of
articles on which silicone compounds are applied, it is preferable to mix
l-chloro-3,3,3-trifluoropropene with 1,1,2,2-tetrafluoro-l-methoxyethane
(HFE-254pc), 1,1,1,3,3-pentafluorobutane (HFC-365mfc),
l,l,2,2-tetrafluoro-l-(2,2,2-trifluoroethoxy)ethane (HFE-347pc-f), methyl
nonafluoroisobutyl ether (HFE-7100), etc.
[0037] As resin members applicable in the case of mixing the
above-exemplified solvents with l-chloro-3,3,3-trifluoropropene, it is
possible to mention, for example, thermosetting resins such as phenol
resin, epoxy resin, polyurethane, etc., thermoplastic resins such as
polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC),
polytetrafluoroethylene (PTFE), acrylic resin (PMMA), polycarbonate

(PC), polyamide (PA), polybutylene terephthalate (PBT), polyethylene
terephthalate (PET), etc., fluororesins such as
tetrafluoroethylene-ethylene copolymer (ETFE),
tetrafluoroethylene-hexafluoropropylene copolymer (FEP), etc.
Furthermore, as rubber members, it is possible to mention, for example,
synthetic rubbers such as nitrile rubber (NBR), styrene-butadiene rubber
(SBR), ethylene-propylene-diene rubber (EPDM), chloroprene rubber
(CR), silicone rubber, urethane rubber, etc., or natural rubber, etc.
[0038] In the case of coating an article made of a resin member or
rubber member with silicone compounds, it is possible to apply silicone
compounds on the surface without adding damages to the article made of
a resin member or rubber member, by adding the above-exemplified
solvents to l-chloro-3,3,3-trifluoropropene. Furthermore, it is possible to
mix one kind of or at least two kinds of the above-exemplified solvents.
[0039] Next, a preferable composition proportion of each component in
specific solvent compositions is explained.
[0040] It is preferable to adjust a preferable composition proportion of
each component in view of solubility of silicone compounds and handling
easiness (flammability, etc.) of the solvent composition for silicone
compounds.
[0041] In the case of mixing 1,1,2,2-tetrafluoro-l-methoxyethane
(HFE-254pc), it is preferable as the mixing percentage to have 40-80
mass % of l-chloro-3,3,3-trifluoropropene and 60-20 mass % of

1,1,2,2-tetrafluoro-l-methoxyethane (HFE-254pc), respectively (see the
after-mentioned Examples 2 and 3).
[0042] Furthermore, as to the mixing percentage, if the mixing
percentage of l-chloro-3,3,3-trifluoropropene is made to be greater than
80 mass %, it may cause damages on resin members such as acrylic,
polycarbonate, etc. Furthermore, if the mixing percentage of
l-chloro-3,3,3-trifluoropropene is made to be less than 40 mass %,
solubility of the silicone compound may become small.
[0043] In the case of mixing 1,1,1,3,3-pentafruorobutane (HF0365mfc),
it is preferable as the mixing percentage to have 60-80 mass % of
l-chloro-3,3,3-trifluoropropene and 40-20 mass % of
1,1,1,3,3-pentafluorobutane (HF0365mfc), respectively (see the
after-mentioned Example 4).
[0044] In the case of mixing
l,l,2,2-tetrafluoro-l-(2,2,2-trifluoroethoxy)ethane (HFE-347pc-f), it is
preferable as the mixing percentage to have 70-80 mass % of
l-chloro-3,3,3-trifluoropropene and 30-20 mass % of
l,l,2,2-tetrafluoro-l-(2,2,2-trifluoroethoxy)ethane(HFE-347pc-f),
respectively (see the after-mentioned Example 5).
[0045]
In the present invention, it is used as a silicone compound coating
solution by mixing the above-mentioned solvent composition for silicone
compounds with a silicone compound. As a silicone compound used in

the present invention, it is possible to use various silicones used, for
example, for surface coating.
[0046] Above all, it is possible to mention straight silicone oils, such as
dimethyl silicone oil, methyl phenyl silicone oil and methyl hydrogen
silicone oil, in which methyl group, phenyl group and hydrogen atom are
bonded as substituents, and modified silicone oils, such as reactive
silicone oil and non-reactive silicone oil, which have a constituent moiety
secondarily derived from straight silicone oils. A solvent composition for
silicone compounds of the present invention is preferable, since it easily
dissolves straight silicones in particular (see Examples).
[0047] Furthermore, it is possible to mention one containing as a main
component a copolymer of aminoalkylsiloxane and dimethylsiloxane,' one
containing as a main component a product derived by reacting a product
of the reaction of an amino group-containing silane and an epoxy
group-containing silane, with a silanol group-containing
polydiorganosiloxane; a silicone mixture of a silicone containing an amino
group at its side chain or terminal and a polydiorganosiloxane; and a
mixture of a silicone obtained by reacting an amino group-containing
alkoxysilane, an epoxy group-containing alkoxysilane, and a silicone
containing silanol groups at its both ends, and a non-reactive silicone; etc.
[0048] It is preferable that the percentage of a silicone compound of the
present invention in the silicone solution for coating is 0.1-80 mass %,
particularly 1-20 mass %. If it is less than 0.1 mass %, it is difficult to
form a coating film having a sufficient film thickness. If it exceeds 80

mass %, it is difficult to obtain a coating film having a uniform film
thickness.
[0049]
In the present invention, the above-mentioned silicone compound
coating solution is applied on the surface of an article, and then the
solvent composition for silicone compounds, such as
l-chloro-3,3,3-trifluoropropene, is removed by evaporation, thereby
forming a film of the silicone compound on the surface of the article. As
an article to which the method of the present invention can be applied, it
can be applied to various materials such as metal member, resin member,
ceramic member, glass member, etc. In particular, it is preferable to
apply that to the needle tube portion of a needle, the spring portion of a
dispenser (liquid quantitative ejection device), etc.
[0050] For example, in the case of application to the needle tube portion
of a needle, etc., as a method for coating the needle tube portion of a
needle with a silicone compound, it is possible to mention a dip coating
method in which the needle tube portion of a needle is immersed in the
silicone compound coating solution to apply it to the outer surface of the
needle tube portion, and then it is permitted to stand at room
temperature or under heating to evaporate the solvent composition,
thereby forming a film of the silicone compound.
EXAMPLES
[0051] Next, the present invention is specifically explained by citing
examples, but the present invention is not limited by these.

[0052] (Solubility test of silicone compound)
According to the following method, a solubility test of the silicone
compound was conducted by using the solvent composition in the present
invention.
[0053] 20g of the solvent compositions shown in Table 1 to Table 5 were
put into glass sample bottles, then a silicone oil (a straight silicone oil
made by Shin-Etsu Chemical Co., Ltd., product name: KF-96-500CS, 100
mass %) in the amounts shown in Table 1 to Table 5 was added dropwise
by O.1g at a time, and solubility was checked visually. The temperature
of the solvent composition was set at ordinary temperature (25°C) to
conduct the solubility test. The amounts (0.1 to 80 g) of the silicone oil
added, which are mentioned in Tables 2-5, represent O.lg, lg, 5g, 30g and
80g of Table 1.
[0054] (Coating and drying characteristics tests)
According to the following method, coating test and drying
characteristics test of silicone compound were conducted by using a
solvent composition for silicone compounds in the present invention.
Silicone compound coating solutions, which were mixtures of solvent
compositions for silicone compounds and silicone oil shown in Table 1 to
Table 5, were applied on various stainless metal plates (SUS), and drying
characteristics were evaluated. Furthermore, the coating films after
drying (natural drying) were checked visually to evaluate coating
properties. Drying characteristics and coating properties are shown in
Table 1 to Table 5.


[0056] From the results of Table 1, solubility of the silicone compound in
the solvent composition of cis-form (Z)-l-chloro-3,3,3-trifluoropropene
alone was good, and it was possible to prepare the silicone compound in
wide concentrations. Furthermore, the coating solutions prepared by
mixing the silicone compound were superior in drying characteristics and
also good in coating properties. As Comparative Example 1-1, solubility
test of the silicone compound was conducted by using a
fluorine-containing unsaturated hydrocarbon, cis-form
(Z)-l,3,3,3-tetrafluoropropene (boiling point: 9°C). With this, it was not
possible to obtain a sufficient solubility, and therefore the application was
not successful.
[0057] Example 2 (Examples 2-1 to 2-2) and Comparative Example 2-1

[0061] For example, in Example 2-1 of Table 2, all of the five test
samples (the amounts of the silicone oil added: O.lg, lg, 5g, 30g, and 80g)
showed the results of Table 2. Similarly, also in each of the other
examples, all of the five test samples showed the results of Tables 2-5.
[0062] From the results of Table 2 and Table 4 to Table 5, even in cases
that other compositions, such as 1,1,2,2-tetrafluoro-l-methoxyethane
(254pc), 1,1,1,3,3-pentafluorobutane (365mfc), and
l,l,2,2-tetrafluoro-l-(2,2,2-trifluoroethoxy)ethane (347pc-f), were added
to cis-form (Z)-l-chloro-3,3,3-trifluoropropene, good solubilities to the
silicone compound were shown, and drying characteristics and coating
properties were also good, by adjusting the mixing ratio.
[0063] Furthermore, from Table 2 and Table 3, even in the case of using
either cis form (Z configuration) or trans form (E configuration) as
l-chloro-3,3,3-trifluoropropene, it is good in solubility, drying
characteristics and coating properties of the silicone compound.
Therefore, it is understood that cis form and trans form of
l-chloro-3,3,3-trifluoropropene have shown comparable solubilities
relative to the silicone compound.
[0064] (Flammability test)

By using a tag closed flash point tester (TAG-E type, made by
Yoshida Kagaku Co.), the measurement of flash point was conducted on
the solvent composition for silicone compounds in the present invention.
[0065] There was conducted the flash point measurement of the solvent
composition for silicone compounds of l-chloro-3,3,3-trifluoropropene and
1,1,2,2-tetrafluoro-l-methoxyethane (HFE-254pc). The flash point was
measured in both cases of cis form (1233Z) and trans form (1233E) as
l-chloro-3,3,3-trifluoropropene.
[0066] As each composition, there was used each of the compositions of
1233Z/254pc = 40/60 (mass ratio), 30/70 (mass ratio), 20/80 (mass ratio)
and 15/85 (mass ratio), 1233E/254pc = 40/60 (mass ratio), 35/65 (mass
ratio) and 20/80 (mass ratio), and 254pc alone as a reference example.
The temperature rise rate in the flash point measurement was set at
l°C/min. The results are shown in Tables 6 and 7.
[0067] From the results of Tables 6 and 7, flash point was not found in
proportions of 1233Z/254pc = 40/60 (mass ratio) and 30/70 (mass ratio),
and 1233E/254pc = 40/60 (mass ratio) and 35/65 (mass ratio). On the
other hand, in proportions of 1233Z/254pc = 20/80 (mass ratio) and 15/85
(mass ratio), and 1233E/254pc = 20/80 (mass ratio), the flash points were
respectively 30°C, 21°C and -6°C.
[0068] It is understood from the results of Table 6 and Table 7 that it
becomes possible to use them as solvent compositions for silicone
compounds, with no flash point and easy handling, by mixing appropriate
proportions of l-chloro-3,3,3-trifluoropropene, of which flash point does

not exist, with 254pc in which alone flash point exists. For example, it is
understood that flash point disappears by adding about 30 mass % or
more of l-chloro-3,3,3-trifluoropropene. Furthermore, it is understood
that there is not a large difference between cis form (1233Z) and trans
form (1233E) in terms of flash point.

[0071] Similarly, there was conducted the flash point measurement of
the solvent composition for silicone compounds of
l-chloro-3,3,3-trifluoropropene and 1,1,1,3,3-pentafluorobutane (365mfc).
The flash point was measured in the case of cis form (1233Z) as
l-chloro-3,3,3-trifluoropropene.
[0072] As each composition, there was used each of the compositions of
1233Z/365mfc = 10/90 (mass ratio) and 5/95 (mass ratio), and 365mfc
alone as a reference example. The temperature rise rate in the flash

point measurement was set at l°C/min. The results are shown in Table
8.
[0073] From the results of Table 8, flash point was not found in
proportions of 1233Z/365mfc = 10/90 (mass ratio) and 5/95 (mass ratio).
[0074] It is understood from the results of Table 8 that the compositions
prepared by mixing 1233Z and 365mfc have almost no flash point, and
therefore handling is very easy in wide mixing composition ratios. It is
understood that flash point can be eliminated by adding 5 mass % or more
of 1233Z.


WE CLAIM
1. A solvent composition for silicone compounds, comprising
l-chloro-3,3,3-trifluoropropene.
2. A solvent composition for silicone compounds, comprising:

(A) l-chloro-3,3,3-trifluoropropene and
(B) a compound made up of at least one selected from the group
consisting of 1,1,2,2-tetrafluoro-l-methoxyethane,
1,1,1,3,3-pentafluorobutane, and
l,l,2,2-tetrafluoro-l-(2,2,2-trifluoroethoxy)ethane.

3. A solvent composition for silicone compounds as claimed in claim
2, comprising 40-80 mass % of the l-chloro-3,3,3-trifluoropropene and
60-20 mass % of the 1,1,2,2-tetrafluoro-l-methoxyethane.
4. A solvent composition for silicone compounds as claimed in claim
2, comprising 60-80 mass % of the l-chloro-3,3,3-trifluoropropene and
40-20 mass % of the 1,1,1,3,3-pentafluorobutane.
5. A solvent composition for silicone compounds as claimed in claim
2, comprising 70-80 mass % of the l-chloro-3,3,3-trifluoropropene and
30-20 mass % of the l,l,2,2-tetrafluoro-l-(2,2,2-trifluoroethoxy)ethane.

6. A silicone compound coating solution, comprising:
a silicone compound and
a solvent composition for silicone compounds according to any one
of claim 1 to claim 5.
7. A silicone compound coating solution as claimed in claim 6, which
is characterized by that the silicone compound is a straight silicone.
8. A method for applying a silicone compound, which is
characterized by that the silicone compound coating solution as claimed
in claim 6 or claim 7 is applied on a surface of an article, and then the
solvent composition for silicone compounds in the coating solution is
removed by evaporation, thereby forming a film of the silicone compound
on the surface of the article.
9. A method for applying a silicone compound as claimed in claim 8,
which is characterized by that the article is metal or resin.

Disclosed is a solvent composition for silicone compounds,
containing 1-chloro-3,3,3-trifluoropropene, or a solvent composition for
silicone compounds, containing (A) 1-chloro-3,3,3-trifluoropropene and (B)
a compound made up of at least one selected from the group consisting of
1,1,2,2-tetrafluoro-1-methoxyethane, 1,1,1,3,3-pentafluorobutane, and
1,1,2,2-tetrafluoro-1-(2,2,2-trifluoroethoxy)ethane. This solvent
composition has characteristics of nonflammability and low toxicity, and
handling is extremely easy. Coating properties of the silicone compound
become good by mixing this solvent composition and the silicone
compound.