Heat medium

Abstract

Disclosed is a heat medium which contains a compound represented by formula (1), and is used for cooling or heating of a constituent member in a semiconductor manufacturing apparatus.　(1): Rf1-CH=CH-Rf2 In formula (1), Rf1 represents a branched fluoroalkyl group having 3 to 6 carbon atoms, and Rf2 represents a fluoroalkyl group having 1 to 6 carbon atoms.

Description

heat medium

[0001] The present invention relates to a heat transfer medium, and more particularly to a heat transfer medium that can be used in low-temperature ranges.

[0002] Heat transfer fluids are used in various heat transfer applications, such as cooling or heating components in semiconductor manufacturing equipment, cooling and heating semiconductor elements and electronic components, temperature control of wafers in semiconductor manufacturing, server cooling, temperature control of heat pumps, temperature control of heat pipes, and temperature control of constant temperature baths.

[0003] The desired properties of a heat transfer medium include, for example, minimizing its environmental impact due to the greenhouse effect, remaining liquid even at low temperatures, and being suitable for use in low-temperature environments.

[0004] Traditionally, perfluorocarbons (PFCs) have been widely used as heat transfer fluids. However, PFCs have a high global warming potential (GWP) and a significant environmental impact due to the greenhouse effect, so there is a need for alternative heat transfer fluids.

[0005] For example, Patent Document 1 contains 1,1,1,2,2,3,3,4,4,7,7,8,8,9,9,10,10,10-octadecafluorodeca-5-ene (CF ３ CF ２ CF ２ CF ２ CH=CHCF ２ CF ２ CF ２ CF ３ It has been noted that it is useful as a heat transfer medium for semiconductor manufacturing processes.

[0006] Japanese Patent Publication No. 2024-64802

[0007] However, the heat transfer medium described in Patent Document 1 did not necessarily have a sufficiently low freezing point at the lower end of the temperature range in which it could maintain its liquid state.

[0008] This invention has been made in view of these circumstances, and aims to provide a heat transfer medium that can be used in low-temperature ranges.

[0009] As a result of intensive studies to solve the above problems, the inventors of the present invention have found that a heat medium containing a compound represented by Rf １ -CH=CH-Rf ２ (Formula (1)) can solve the above problems, and thus the present invention has been completed. Here, Rf １ is a branched fluoroalkyl group having 3 to 6 carbon atoms, and Rf ２ is a fluoroalkyl group having 1 to 6 carbon atoms.

[0010] The present invention is as follows. [1] A heat medium containing a compound represented by the following formula (1) and used for cooling or heating a component in a semiconductor manufacturing apparatus. Rf １ -CH=CH-Rf ２ (1) In formula (1), Rf １ is a branched fluoroalkyl group having 3 to 6 carbon atoms, and Rf ２ is a fluoroalkyl group having 1 to 6 carbon atoms. [2] The heat medium according to [1] above, wherein Rf １ is a branched fluoroalkyl group having 3 to 4 carbon atoms. [3] The heat medium according to [1] or [2] above, wherein the content of the compound represented by formula (1) is 50% by mass or more in 100% by mass of the heat medium. [4] The heat medium according to any one of [1] to [3] above, wherein the compound represented by formula (1) is at least one selected from 1,1,1,2,2,5,6,6,6-nonafluoro-5-(trifluoromethyl)hexa-3-ene and 1,1,1,2,5,5,6,6,7,7,8,8,8-tridecafluoro-2-(trifluoromethyl)octa-3-ene. [5] The heat medium according to any one of [1] to [4] above, wherein the compound represented by formula (1) is at least one selected from 1,1,1,2,2,5,6,6,6-nonafluoro-5-(trifluoromethyl)hexa-3-ene (E) and 1,1,1,2,5,5,6,6,7,7,8,8,8-tridecafluoro-2-(trifluoromethyl)octa-3-ene (E). [6] The heat medium according to any one of [1] to [5] above, further containing water, and the content of the water is 1 to 100 mass ppm in 100% by mass of the heat medium.

[0011] According to the present invention, a heat transfer medium that can be used in low-temperature ranges can be provided.

[0012] This is a schematic diagram of the fluid electrostatic testing apparatus used in the example.

[0013] The present invention will now be described in detail. In this specification, preferred provisions can be adopted at will, and combinations of preferred provisions are considered more preferred. In this specification, the notation "XX to YY" means "XX or more and YY or less". In this specification, the lower and upper limits of preferred numerical ranges (for example, ranges of content, etc.) described in steps can be combined independently. For example, from the notation "preferably 10 to 90, more preferably 30 to 60", the "preferred lower limit (10)" and the "more preferred upper limit (60)" can be combined to get "10 to 60". Also, in numerical ranges described in this specification, the upper or lower limit of the numerical range may be replaced with the values ​​shown in the examples. In this specification, "GWP" means an estimated value obtained by accumulating the intensity of the greenhouse effect (radiant energy given to the Earth) per unit concentration when the target substance is released into the atmosphere over 100 years, with carbon dioxide as the base 1. In this specification, "GWP of the compound represented by formula (1)" means an estimated value calculated based on the GWP value and chemical structure of a known heat transfer medium containing a fluorine-containing compound (hereinafter sometimes simply referred to as "fluorine-based heat transfer medium"). Also in this specification, "GWP of the heat transfer medium" means an estimated value calculated from the weighted average of the GWP of the compound contained in the heat transfer medium (an estimated value calculated based on the GWP value and chemical structure of a known fluorine-based heat transfer medium) and the compositional mass ratio of the compound. In this specification, "ODP" means a numerical value representing the relative amount of ozone depletion caused to the ozone layer when the target substance is released into the atmosphere, with the ozone depletion amount per 1 kg of CFC-11 (trichlorofluoromethane) set as the baseline of 1.0. In this specification, "branched fluoroalkyl group" means a branched alkyl group in which at least one hydrogen atom bonded to the carbon atoms constituting the branched alkyl group is substituted with a fluorine atom. In this specification, "fluoroalkyl group" means an alkyl group in which at least one hydrogen atom bonded to the carbon atoms constituting the alkyl group is substituted with a fluorine atom. In this specification, "low temperature range" means below -40°C.

[0014] [Heat Transfer Medium] The heat transfer medium of the embodiment of the present invention (hereinafter sometimes simply referred to as "this embodiment") comprises a compound represented by the following formula (1) (hereinafter sometimes simply referred to as "compound (1)"), and is not particularly limited as long as it is used for cooling or heating components in semiconductor manufacturing equipment. It may further contain water, other compounds that function as a heat transfer medium (compounds different from compound (1)), and other components as needed. Rf １ -CH = CH - Rf ２ (1) In the above formula (1), Rf １ Rf is a branched fluoroalkyl group having 3 to 6 carbon atoms. ２ These are fluoroalkyl groups having 1 to 6 carbon atoms.

[0015] There are no particular restrictions on the boiling point of the heat transfer medium, but from the viewpoint of suppressing environmental release due to volatilization, it is preferably 20°C or higher, more preferably 40°C or higher, and particularly preferably 60°C or higher. The boiling point of the heat transfer medium can be determined by the measurement method described in the examples.

[0016] There are no particular restrictions on the solidification point of the heat transfer medium, but it is preferably -50°C or lower, more preferably -60°C or lower, even more preferably -70°C or lower, and most preferably -80°C or lower. The solidification point of the heat transfer medium can be determined by the measurement method described in the examples.

[0017] There are no particular restrictions on the volume resistivity of the above-mentioned heat transfer medium, but from the viewpoint that a higher volume resistivity results in higher insulation properties of the heat transfer medium and is suitable for application in the field of electronics, a volume resistivity of 1.0 × 10⁻⁶ is preferred. ９ Ω·cm or more, more preferably 1.0 × 10 １０ Ω·cm or more, particularly preferably 1.0 × 10⁻⁶ １１ It is Ω·cm or greater. The volume resistivity of the heat transfer medium can be determined by the measurement method described in the examples.

[0018] There are no particular restrictions on the GWP of the heat transfer medium, but from the viewpoint of minimizing the environmental impact due to the greenhouse effect, it is preferably 1000 or less, more preferably 500 or less, and particularly preferably less than 100. The GWP of the heat transfer medium can be determined by the method described in the examples.

[0019] There are no particular restrictions on the ODP of the heat transfer medium, but it is preferably 0 from the viewpoint of minimizing the environmental impact due to the greenhouse effect. The ODP of the heat transfer medium can be determined by the method described in the examples.

[0020] Furthermore, fluorine-containing compounds have high electrical insulation properties and tend to accumulate static electricity. Therefore, when a fluorine-based heat transfer medium is circulated in a non-conductive pipe, a phenomenon called flow charging occurs, and the medium becomes easily charged with static electricity. Since a charged heat transfer medium may adversely affect the constituent materials of the heat transfer medium's flow path due to partial discharge, it is preferable that the heat transfer medium does not undergo flow charging. There are no particular limitations on the potential difference that may be generated by the flow charging of the heat transfer medium in this embodiment, but from the above viewpoint, it is preferably -0.5 to 0.5 kV, and more preferably -0.5 to 0 kV. The potential difference generated by the flow charging of the heat transfer medium can be determined by the measurement method described in the example.

[0021] <Compound (1)> Compound (1) contained in the heat transfer medium of this embodiment is hydrofluoroolefin (hereinafter sometimes simply referred to as "HFO"). HFO has a carbon-carbon double bond that is easily decomposed by reactive oxygen species such as hydroxyl radicals in the atmosphere. Therefore, HFO has a short atmospheric lifetime and a low GWP, and can be said to be a compound that has little impact on the environment due to the greenhouse effect. The ODP of compound (1) is 0 because compound (1) is HFO and HFO does not contain halogens other than fluorine.

[0022] The content of compound (1) is not particularly limited, but from the viewpoint of fully exhibiting the effects of the present invention (providing a heat transfer medium that can be used in low-temperature ranges), it is preferably 50% by mass or more, more preferably 70% by mass or more, and particularly preferably 90% by mass, of 100% by mass of the heat transfer medium. The heat transfer medium may also consist of compound (1). In this specification, "the heat transfer medium consists of compound (1)" means that nothing other than compound (1) is intentionally added to the heat transfer medium, and does not exclude the content of other substances that are inevitably mixed in from raw materials, etc., to an extent that does not affect the desired properties.

[0023] There are no particular restrictions on the geometric isomer of compound (1) described above; it may be the (E) isomer or the (Z) isomer. Among these, the (E) isomer is preferred. In this specification, compound (1) and specific examples of compound (1) described later refer to the (E) isomer and / or the (Z) isomer unless otherwise specified. In this specification, "XX(E)" means the (E) isomer of XX; for example, "compound (1)(E)" means the (E) isomer of compound (1), and "1,1,1,2,2,5,6,6,6-nonafluoro-5-(trifluoromethyl)hexa-3-ene(E)" means the (E) isomer of 1,1,1,2,2,5,6,6,6-nonafluoro-5-(trifluoromethyl)hexa-3-ene. Furthermore, in this specification, "XX (Z)" means the (Z) form of XX. For example, "compound (1) (Z)" means the (Z) form of compound (1), and "1,1,1,2,2,5,6,6,6-nonafluoro-5-(trifluoromethyl)hexa-3-ene (Z)" means the (Z) form of 1,1,1,2,2,5,6,6,6-nonafluoro-5-(trifluoromethyl)hexa-3-ene.

[0024] There are no particular restrictions on the ratio of the (E) isomer of compound (1) above, but the ratio ((E) isomer / (Z) isomer), which is expressed as the ratio of the content of the (E) isomer in compound (1) to the content of the (Z) isomer in compound (1), is preferably 80 / 20 to 100 / 0, and more preferably 90 / 10 to 100 / 0. If it is above the lower limit of the above range, the freezing point of the heat transfer medium tends to decrease. The content of the (E) isomer of compound (1) can be determined by the measurement method described in the examples.

[0025] There are no particular restrictions on the proportion of fluorine atoms contained in the above compound (1), but from the viewpoint of raising the flash point or eliminating the flash point, it is preferably 55% or more, more preferably 70% or more, and particularly preferably 85% or more, relative to the total number of hydrogen atoms and fluorine atoms.

[0026] (Rf １ ) The above Rf １ As long as it is a branched fluoroalkyl group having 3 to 6 carbon atoms, there are no particular restrictions, but it is preferably a branched fluoroalkyl group having 3 to 4 carbon atoms, and more preferably a branched fluoroalkyl group having 3 carbon atoms. If the number of carbon atoms is below the upper limit of the above range, the freezing point tends to be low.

[0027] The above GF １ There are no particular restrictions on the proportion of fluorine atoms contained, but from the viewpoint of raising the flash point or eliminating the flash point, it is preferably 55% or more, more preferably 70% or more, even more preferably 85% or more, and especially preferably 100% relative to the total number of hydrogen atoms and fluorine atoms. １ There are no particular restrictions on the proportion of hydrogen atoms contained, but from the viewpoint of raising the flash point, it is preferably 45% or less, more preferably 30% or less, even more preferably 15% or less, and especially preferably 0% relative to the total number of hydrogen atoms and fluorine atoms.

[0028] The above-mentioned branched fluoroalkyl groups having 3 to 6 carbon atoms refer to groups in which at least one hydrogen atom bonded to a carbon atom constituting the branched alkyl group having 3 to 6 carbon atoms is substituted with a fluorine atom. There are no particular limitations on the above-mentioned branched alkyl groups having 3 to 6 carbon atoms, and examples include isopropyl group, 1-methylpropyl group, 2-methylpropyl group, t-butyl group, 1,1-dimethylpropyl group, 2,2-dimethylpropyl group, 1,2-dimethylpropyl group, 1-ethylpropyl group, 2-ethylpropyl group, 1,1-diethylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1,1-dimethylbutyl group, 2,2-dimethylbutyl group, and 3,3-dimethylbutyl group. Among these, the above-mentioned branched fluoroalkyl groups having 3 to 6 carbon atoms are preferably those in which at least one hydrogen atom bonded to a carbon atom constituting the isopropyl group is substituted with a fluorine atom, and perfluoroisopropyl group, in which all hydrogen atoms of the isopropyl group are substituted with fluorine atoms, is more preferred.

[0029] (Rf ２ ) The above Rf ２ As long as the fluoroalkyl group has 1 to 6 carbon atoms, there are no particular restrictions, but it is preferably a fluoroalkyl group with 2 to 4 carbon atoms. If the carbon number is below the upper limit of the above range, the freezing point tends to be lower. The fluoroalkyl group may be branched or linear. Among these, the linear form is preferred from the viewpoint of raw material availability.

[0030] The above GF ２ There are no particular restrictions on the proportion of fluorine atoms contained, but from the viewpoint of raising the flash point or eliminating the flash point, it is preferably 55% or more, more preferably 70% or more, even more preferably 85% or more, and especially preferably 100% relative to the total number of hydrogen atoms and fluorine atoms. ２ There are no particular restrictions on the proportion of hydrogen atoms contained, but from the viewpoint of raising the flash point, it is preferably 45% or less, more preferably 30% or less, even more preferably 15% or less, and especially preferably 0% relative to the total number of hydrogen atoms and fluorine atoms.

[0031] The above-mentioned fluoroalkyl groups having 1 to 6 carbon atoms refer to groups in which at least one hydrogen atom bonded to a carbon atom constituting the alkyl group having 1 to 6 carbon atoms is substituted with a fluorine atom. There are no particular restrictions on the alkyl groups having 1 to 6 carbon atoms, and examples include branched alkyl groups having 3 to 6 carbon atoms such as isopropyl group, 1-methylpropyl group, 2-methylpropyl group, t-butyl group, 1,1-dimethylpropyl group, 2,2-dimethylpropyl group, 1,2-dimethylpropyl group, 1-ethylpropyl group, 2-ethylpropyl group, 1,1-diethylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1,1-dimethylbutyl group, 2,2-dimethylbutyl group, and 3,3-dimethylbutyl group; and linear alkyl groups having 1 to 6 carbon atoms such as methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, and n-hexyl group. Among these, the fluoroalkyl groups having 1 to 6 carbon atoms are preferably those in which at least one hydrogen atom bonded to the carbon atoms constituting the ethyl group or n-butyl group is substituted with a fluorine atom, and perfluoroethyl groups and n-perfluorobutyl groups, in which all hydrogen atoms of the ethyl group or n-butyl group are substituted with fluorine atoms, are more preferred.

[0032] The above compound (1) is not particularly limited, and examples include 1,1,1,2,2,5,6,6,6-nonafluoro-5-(trifluoromethyl)hexa-3-ene (hereinafter sometimes simply referred to as "HFO-163-12"), 1,1,1,2,5,5,6,6,7,7,8,8,8-tridecafluoro-2-(trifluoromethyl)octa-3-ene (hereinafter sometimes simply referred to as "HFO-183-16"). These may be used individually or in combination of two or more.

[0033] As mentioned above, the compound (1) is preferably in its (E) form from the viewpoint of lowering the freezing point of the heat transfer medium. Examples of compound (1)(E) include 1,1,1,2,2,5,6,6,6-nonafluoro-5-(trifluoromethyl)hexa-3-ene(E) (hereinafter sometimes simply referred to as "HFO-163-12(E)"), 1,1,1,2,5,5,6,6,7,7,8,8,8-tridecafluoro-2-(trifluoromethyl)octa-3-ene(E) (hereinafter sometimes simply referred to as "HFO-183-16(E)"). These may be used individually or in combination of two or more.

[0034] The method for producing the above compound (1) is not particularly limited and can be carried out by known methods.

[0035] <Water> The heat transfer medium of this embodiment may further contain water as needed. There are no particular restrictions on the amount of water, but it is preferably 0.1 to 500 ppm by mass, more preferably 1 to 100 ppm by mass, and most preferably 3 to 70 ppm by mass, per 100% by mass of the heat transfer medium. If the amount is above the lower limit of the above range, it is easier to suppress the occurrence of flow charging of the heat transfer medium, and if it is below the upper limit of the above range, it is less likely to cause non-uniformity of the heat transfer medium due to phase separation, so the electrical properties of the heat transfer medium are less likely to decrease.

[0036] <Other Compounds> The heat transfer medium of this embodiment may, if necessary, further contain other compounds that function as a heat transfer medium (compounds different from compound (1)) (hereinafter sometimes simply referred to as "other compounds"), as long as they do not impair the effects of the present invention. There are no particular restrictions on the content of the above other compounds, but from the viewpoint of fully exhibiting the effects of the present invention, it is preferably 50% by mass or less, more preferably 30% by mass or less, and particularly preferably 10% by mass or less, of 100% by mass of the heat transfer medium.

[0037] Other compounds mentioned above are not particularly limited as long as they are not compound (1). Examples include HFO, hydrofluoroether (HFE), hydrofluorocarbon (HFC), perfluoroolefin (PFO), perfluoroether (PFE), perfluorocarbon (PFC), hydrochlorofluoroolefin (HCFO), hydrochlorofluorocarbon (HCFC), etc., that do not fall under compound (1). These may be used individually or in combination of two or more.

[0038] <Other Components> The heat transfer medium of this embodiment may further contain other components as needed, within a range that does not impair the effects of the present invention. There are no particular restrictions on the content of the above-mentioned other components, but from the viewpoint of fully exhibiting the effects of the present invention, it is preferably 10% by mass or less, more preferably 5% by mass or less, and particularly preferably 3% by mass or less, based on 100% by mass of the heat transfer medium.

[0039] The other components mentioned above are not particularly limited and include, for example, fluorine-based solvents and stabilizers. These may be used individually or in combination of two or more.

[0040] There are no particular restrictions on the above-mentioned fluorine-based solvents; for example, Solvay's Galden (registered trademark) HT90 / 110 / 135 / 150 / 200 (all of the above, CF ３ - [OCF (CF ３ ) (CF ２ ) ｎ (OCF ２ ) ｍ ]-CF ３ ), ZV90, SVX, ZT-180; FTM-110 / 135 / 150 / 170 / 200 / 230 / 270 manufactured by Sanming Hexafluo Chemicals Co., Ltd.; Fluorinert (registered trademark) FC-75 (C) manufactured by 3M. ８ F ８ ) / 3283((C ３ F ７ ) ３ N) / 40((C ４ F ９ ) ３ N) / 43((C ４ F ９ )３ N) / 70((C ５ F １１ ) ３ N), FX-3300((C ８ F ８ ), Novec 7100((CF ３ (CF ２ ) ３ OCH ３ and (CF ３ ) ２ CF CF ２ OCH ３ of the mixture) / 7200((CF ３ (CF ２ ) ３ OC ２ H ５ and (CF ３ ) ２ CF CF ２ OC ２ H ５ of the mixture) / 7300((CF ３ ) ２ CF CF(CF ２ CF ３ )OCH ３ ) / 7500((CF ３ CF ２ CF ２ CF(OCH ２ CH ３ )CF(CF ３ )CF ３ ) / 7600((CF ３ CFHCF ２ OC(CH ３ )CF ２ CFHCF ３ ); Optem (registered trademark) SF10 / 30 manufactured by KEMARS ((CF ３ CH=CHCF ３ and the mixture of CClH = CClH) / 33((CF ３ CH=CHCF ３ ) / 2P50; Asahiklin (registered trademark) AC-2000 manufactured by AGC, Inc. ((CF ３ CF ２ CF ２ CF ２ CF ２ CF ２ H) / 6000((CF ３ CF ２ CF ２ CF２ CF ２ CF ２ CH ２ CH ３ ), Amorea (registered trademark) AS-300 (CF ２ HCF = CClH), CELEFIN (registered trademark) 1233Z (CF) manufactured by Central Glass Co., Ltd. ３ Examples of commercially available products include CH=CClH.

[0041] There are no particular restrictions on the stabilizers, and examples include phenol compounds, unsaturated hydrocarbon group-containing aromatic compounds, aromatic amine compounds, aromatic thiazine compounds, terpene compounds, quinone compounds, nitro compounds, epoxy compounds, orthoester compounds, etc.

[0042] <Applications of the heat transfer medium> There are no particular limitations on the applications of the heat transfer medium in this embodiment. Examples include cooling or heating components in semiconductor manufacturing equipment, cooling and heating semiconductor elements and electronic components, temperature control of wafers in semiconductor manufacturing, server cooling, temperature control of heat pumps, temperature control of heat pipes, and temperature control of constant temperature baths. Among these, compound (1) is suitable for use in cooling and heating semiconductor elements and electronic components from the viewpoint that it can be used in low temperature ranges.

[0043] The present invention will be described in detail below based on examples, but the present invention is not limited to the following examples, and various modifications are possible without departing from the spirit of the invention. Examples 2, 4, and 6-7 are examples, and examples 1, 3, and 5 are comparative examples.

[0044] <Identification of Compounds> The identification of the synthesized compounds and intermediates described later (including the ratio of the content of the (E) isomer to the content of the (Z) isomer in the compound, the content of the intermediate, etc.) was performed using a nuclear magnetic resonance spectrometer (Brker, AVANCE NEO400) and proton nuclear magnetic resonance ( １ Fluorine-19 nuclear magnetic resonance (H NMR), using a nuclear magnetic resonance spectrometer (Brker, AVANCE NEO400) １９ The procedure was performed using F NMR.

[0045] [Synthesis of Compounds] Compounds 1 to 5 were synthesized as shown in the following synthesis examples 1 to 5. Compounds 2 and 4 are compound (1) of the present invention.

[0046] (Synthesis Example 1) The crude solution obtained according to the method described in Example 1 of International Publication No. 2023 / 164093 was purified by distillation to obtain compound 1 ((E) isomer / (Z) isomer: 100 / 0) represented by the following structural formula (10).

[0047] ... Structural formula (10)

[0048] (Synthesis Example 2) In a stainless steel autoclave (internal volume 0.5 liters) equipped with a stirrer, 616 g of heptafluoro-2-iodopropane and 5.54 g of t-butylperoxybenzoate were added, stirred, and heated to 130°C. While continuing to stir, 150 g of 3,3,4,4,4-pentafluoro-1-butene was continuously added over 1 hour, and after the addition was completed, the mixture was held at 130°C for 2 hours. After the reaction was complete, the crude reaction solution was collected from the autoclave. The collected crude reaction solution contained 45% by mass of intermediate 2, represented by the following structural formula (2), out of 100% by mass of the crude reaction solution. In a glass reactor (internal volume 0.5 liters) equipped with a stirrer, 389 g of 48% by mass potassium hydroxide aqueous solution, 545 g of water, and 379 g of 2-propanol were added, stirred, and heated to 30°C. While stirring was continued, 766 g of the crude solution containing the above intermediate 2 was added intermittently over 1 hour, and after the addition was completed, the mixture was held at 30°C for 1 hour. After the reaction was complete, the organic layer was collected, washed with water, and then purified by distillation to obtain compound 2 (HFO-163-12(E)) ((E)-isomer / (Z)-isomer: 100 / 0) represented by the following structural formula (20).

[0049] ...Structural formula (2)

[0050] ...Structural formula (20)

[0051] (Synthesis Example 3) In Synthesis Example 2, 280 g of nonafluoro-1-iodobutane was used instead of 616 g of heptafluoro-2-iodopropane. Also in Synthesis Example 2, the amount of t-butylperoxybenzoate added was changed from 5.54 g to 1.19 g. Also in Synthesis Example 2, the amount of 3,3,4,4,4-pentafluoro-1-butene added was changed from 150 g to 30.4 g. Also in Synthesis Example 2, intermediate 3 (content of intermediate 3 in 100% by mass of the crude reaction solution: 30% by mass), represented by the following structural formula (3), was obtained instead of intermediate 2 (content of intermediate 2 in 100% by mass of the crude reaction solution: 45% by mass). Furthermore, in Synthesis Example 2, 308 g of crude solution containing intermediate 3 was used instead of 766 g of crude solution containing intermediate 2. Except as described above, compound 3 ((E)-isomer / (Z)-isomer: 100 / 0) represented by the following structural formula (30) was obtained by the same method as in Synthesis Example 2.

[0052] ...Structural formula (3)

[0053] ...Structural formula (30)

[0054] (Synthesis Example 4) In Synthesis Example 2, 3,3,4,4,4-pentafluoro-1-butene 150 g was replaced with 3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene 200 g. Also in Synthesis Example 2, the amount of t-butylperoxybenzoate added was changed from 5.54 g to 4.77 g. Also in Synthesis Example 2, the amount of heptafluoro-2-iodopropane added was changed from 616 g to 528 g. Also in Synthesis Example 2, intermediate 4 (content of intermediate 4 in 100% by mass of the crude reaction solution: 51% by mass), represented by the following structural formula (4), was obtained instead of intermediate 2 (content of intermediate 4 in 100% by mass of the crude reaction solution: 45% by mass). Furthermore, in Synthesis Example 2, crude solution containing intermediate 4 727 g was used instead of crude solution containing intermediate 2 766 g. Except as described above, compound 4 (HFO-183-16(E)) ((E)-isomer / (Z)-isomer: 100 / 0), represented by the following structural formula (40), was obtained by the same method as in Synthesis Example 2.

[0055] ...Structural formula (4)

[0056] ...Structural formula (40)

[0057] (Synthesis Example 5) In Synthesis Example 4, 94.5 g of heptafluoro-1-iodopropane was used instead of 616 g of heptafluoro-2-iodopropane. Also in Synthesis Example 4, the amount of t-butylperoxybenzoate added was changed from 4.77 g to 0.90 g. Also in Synthesis Example 4, the amount of 3,3,4,4,5,5,6,6,6-nonafluoro-1-hexene added was changed from 200 g to 37.3 g. Also in Synthesis Example 4, intermediate 5 (content of intermediate 4 in 100% by mass of the crude reaction solution: 51% by mass), represented by the following structural formula (5), was obtained instead. Furthermore, in Synthesis Example 4, 128 g of crude solution containing intermediate 5 was used instead of 727 g of crude solution containing intermediate 4. Except as described above, compound 5 ((E)-isomer / (Z)-isomer: 100 / 0), represented by the following structural formula (50), was obtained by the same method as in Synthesis Example 4.

[0058] ...Structural formula (5)

[0059] ...Structural formula (50)

[0060] [Preparation of heat transfer medium] (Examples 1-5) Heat transfer mediums containing only compounds 1-5 synthesized in the above synthesis examples 1-5 were used as the heat transfer mediums for Examples 1-5 shown in Table 1.

[0061] (Example 6) Deionized water was added to the heat transfer medium of Example 4 to prepare the heat transfer medium of Example 6, which contained the amount of water shown in Table 2.

[0062] (Example 7) Deionized water was added to the heat transfer medium of Example 4 to prepare the heat transfer medium of Example 7, which contained the amount of water shown in Table 2.

[0063] [Measurement of physical properties of heat transfer fluids in Examples 1-5] The following measurements were performed on the heat transfer fluids in Examples 1-5. The results obtained are shown in Table 1.

[0064] <Measurement of Boiling Point> In accordance with the test method for the equilibrium reflux boiling point of JIS K2233:2017, round-bottom flasks containing each of the above examples of heat transfer fluids were heated using a mantle heater under atmospheric pressure, refluxed using a condenser through which water was passed, and the measured reflux temperature was corrected to the value at standard atmospheric pressure (101.325 kPa) to determine the boiling point of each example of heat transfer fluid.

[0065] <Measurement of Freezing Point> The freezing point of each heat transfer medium was measured using a differential scanning calorimetry (DSC) system (Hitachi High-Tech Science Corporation, "DSC7000X").

[0066] <Measurement of Volume Resistivity> The volume resistivity of the heat transfer fluid in each example was measured using a digital ultra-high resistance / micro-current meter (ADC Corporation, "Model 5450").

[0067] <GWP> Estimated GWP values ​​were calculated based on the GWP values ​​and chemical structures of known fluorine-based heat transfer fluids.

[0068] <ODP> If the heat transfer fluids in Examples 1 to 5 do not contain halogens other than fluorine, the ODP will be 0. Therefore, the ODP of the heat transfer fluids in each example is 0.

[0069]

[0070] As can be seen from the measurement results shown in Table 1, the heat transfer fluids of the present invention (Examples 2 and 4) were found to have lower freezing points compared to heat transfer fluids other than those of the present invention (Examples 1, 3, and 5). Therefore, it can be said that the heat transfer fluids of the present invention (Examples 2 and 4) are more suitable for use in low-temperature ranges compared to heat transfer fluids other than those of the present invention (Examples 1, 3, and 5).

[0071] [Measurement of physical properties of heat transfer fluids in Examples 6 and 7] In addition to the measurements described above, the following measurements were performed on the heat transfer fluids in Examples 6 and 7. The obtained measurement results are shown in Table 2.

[0072] <Measurement of moisture content> The moisture content in the heat transfer medium for each example was measured using a Karl Fischer moisture meter (Nitto Seikou Analytech Co., Ltd., "CA-100").

[0073] <Measurement of Flow Charging> The flow charging of the heat transfer fluid in each example was measured using the test apparatus shown in Figure 1. The test apparatus shown in Figure 1 consists of a liquid reservoir 1 for the heat transfer fluid, a pump 3 for circulating the heat transfer fluid through piping 2, a metal rod 4 (made of SUS316), and a potentiometer (not shown). The piping 2 was made of a flexible polyvinyl chloride hose (Toyox Co., Ltd., "Toyolon (registered trademark) TR-4": inner diameter 4 mm, length 15 cm). A digital electrostatic potential meter (Kasuga Electric Co., Ltd., "KSD-2000") was used. The heat transfer fluid was circulated through piping 2 at a flow rate of 5.5 L / min under room temperature (25°C) conditions, and the potential difference between the metal rod 4 and the heat transfer fluid was measured after 10 minutes. The results are shown in Table 2. Fluorine-containing compounds have high electrical insulation properties and tend to accumulate static electricity; therefore, when fluorine-based heat transfer fluids are continuously circulated in non-conductive piping, flow charging occurs, and the amount of charge on the heat transfer fluid tends to increase. Note that the smaller the value of fluid charging in Table 2 (i.e., the larger the absolute value of the potential difference), the greater the negative charge of the heat transfer medium.

[0074]

[0075] As can be seen from the measurement results shown in Table 2, the heat transfer fluids of the present invention (Examples 6-7) were found to have lower freezing points compared to heat transfer fluids other than those of the present invention (Example 1 in Table 1, Example 3 in Table 1, and Example 5 in Table 1). Therefore, it can be said that the heat transfer fluids of the present invention (Examples 6-7) are more suitable for use in low-temperature ranges compared to heat transfer fluids other than those of the present invention (Example 1 in Table 1, Example 3 in Table 1, and Example 5 in Table 1). Furthermore, as can be seen from the measurement results shown in Table 2, it was found that the heat transfer fluids of the present invention (Examples 6-7) are not only suitable for use in low-temperature ranges but also suppress the generation of flow charge.

[0076] 1. Liquid reservoir 2. Piping 3. Pump 4. Metal rod

Claims

1. A heat transfer medium containing a compound represented by the following formula (1), used for cooling or heating components in semiconductor manufacturing equipment. Rf １ -CH = CH - Rf ２ (1) In formula (1), Rf １ Rf is a branched fluoroalkyl group having 3 to 6 carbon atoms. ２ These are fluoroalkyl groups having 1 to 6 carbon atoms.

2. The Rf １ The heat transfer medium according to claim 1, wherein is a branched fluoroalkyl group having 3 to 4 carbon atoms.

3. The heat transfer medium according to claim 1 or 2, wherein the content of the compound represented by formula (1) is 50% by mass or more in 100% by mass of the heat transfer medium.

4. The heat transfer medium according to claim 1 or 2, wherein the compound represented by formula (1) is at least one selected from 1,1,1,2,2,5,6,6,6-nonafluoro-5-(trifluoromethyl)hexa-3-ene and 1,1,1,2,5,5,6,6,7,7,8,8,8-tridecafluoro-2-(trifluoromethyl)octa-3-ene.

5. The heat transfer medium according to claim 1 or 2, wherein the compound represented by formula (1) is at least one selected from 1,1,1,2,2,5,6,6,6-nonafluoro-5-(trifluoromethyl)hexa-3-ene (E) and 1,1,1,2,5,5,6,6,7,7,8,8,8-tridecafluoro-2-(trifluoromethyl)octa-3-ene (E).

6. The heat transfer medium according to claim 1 or 2, further comprising water, wherein the water content is 1 to 100 ppm by mass in 100% by mass of the heat transfer medium.

Images