Mixed solvent composition

Abstract

To provide a novel dry cleaning solvent designed for the next generation with minimized environmental impact.SOLUTION: A composition for dry cleaning solvent contains a fluorine-based solvent with a boiling point of lower than 40°C.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a novel dry cleaning solvent. [Background technology]

[0002] Dry cleaning is a cleaning method that uses organic solvents to remove stains. Various organic solvents are selected for dry cleaning (dry cleaning solvents) depending on the type of clothing they are used for, but examples include chlorine-based (perchloroethylene, etc.), petroleum-based (No. 5 industrial gasoline, etc.), and fluorine-based solvents.

[0003] Among these, fluorine-based dry cleaning solvents have been used mainly for high-end clothing because of their safety during handling, prevention of damage to clothing, and good texture after finishing. However, due to recent environmental impact issues, hydrochlorofluorocarbons (HCFCs) used in dry cleaning have already been completely banned in developed countries, and the production of hydrofluorocarbons (HFCs) has also been severely restricted by the Paris Protocol and the Kigali Amendment of the Montreal Protocol. Furthermore, hydrofluoroethers (HFEs) such as hydrofluoroethers (HFE347pc and HFE-449) have also been used in part as dry cleaning solvents (Patent Document 1), but they have issues such as safety, price, and supply. HFEs are also used as mixtures with HFCs to compensate for such defects, but as mentioned above, production restrictions have been initiated for HFCs, and they may no longer be usable in the near future, so it is unclear whether such mixtures will be usable in the future. Recently, hydrochlorofluoroolefins (HCFOs) have been proposed as alternatives to these (Patent Document 2), but they have the problem of being highly damaging to clothing.

[0004] When selecting a fluorine-based solvent as a dry cleaning solvent, it is also necessary to select it from the viewpoint of the burden on the environment. The use of HCFCs has been completely banned in developed countries because they are ozone-depleting substances with a high ozone depletion potential. Although HFCs do not have a high ozone depletion potential, they are known to have a high global warming potential, and their use is not recommended from the perspective of the global environment.

[0005] Furthermore, although this is not limited to fluorine-based dry cleaning solvents, consideration of VOCs is also necessary as a problem for all dry cleaning solvents. VOCs are volatile organic compounds, which refer to organic compounds that are gaseous when emitted or dispersed into the atmosphere, and are substances that cause photochemical oxidants that cause photochemical smog and suspended particulate matter that affects respiratory health (Non-Patent Documents 1 and 2). It has been pointed out that dry cleaning solvents are one of the sources of VOCs, and various attempts are being made, such as installing solvent vapor recovery devices in cleaning machines and using dry cleaning solvents with high boiling points (Non-Patent Document 3). From the perspective of preventing air pollution and the health of workers who handle dry cleaning solvents, dry cleaning solvents with low VOC diffusion are desired. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 3336356 [Patent Document 2] JP 2018-031011 A [Non-patent literature]

[0007] [Non-Patent Document 1] "The current state of the cleaning industry and efforts to reduce dry cleaning solvents" (National Federation of Cleaning and Hygiene Trade Associations (https: / / www.env.go.jp / council / former2013 / 07air / y074-07 / mat03_2.pdf) [Non-Patent Document 2] "Current status and issues of volatile organic compounds countermeasures" (10th Tokyo Metropolitan Research Institute for Environmental Protection open research presentation) (https: / / www.tokyokankyo.jp / kankyoken_contents / research-meeting / h17-01 / 1701-pp.pdf) [Non-Patent Document 3] "Manual for reducing and abolishing 1,1,1-trichloroethane" (Ozone Layer Protection Industry Council, 1993) Summary of the Invention [Problem to be solved by the invention]

[0008] An object of the present invention is to provide a new, next-generation, environmentally friendly dry cleaning solvent composition. [Means for solving the problem]

[0009] As a result of extensive investigations aimed at solving the above problems, the present inventors have discovered the use of a specific fluorine-based solvent as a dry cleaning solvent, and have thus completed the present invention. That is, the present invention is characterized by the following points. [1] A composition for use as a dry cleaning solvent, comprising a fluorinated solvent having a boiling point of less than 40°C. [2] A dry cleaning solvent composition according to [1], comprising a soap. [3] The dry cleaning solvent composition according to [1] or [2], wherein the fluorine-based solvent having a boiling point of less than 40°C includes either 1,1,1,4,4,4-hexafluoro-2-butene and / or 1-chloro-3,3,3-trifluoropropene. [4] The dry cleaning solvent composition according to [1] or [2], further comprising a fluorine-containing solvent having a boiling point of 40°C or higher. Effect of the Invention

[0010] According to the present invention, a novel dry cleaning solvent composition with an extremely low environmental impact can be provided. In particular, a dry cleaning solvent with low VOC diffusion can be provided from the viewpoint of preventing air pollution and from the viewpoint of the health of workers who handle the dry cleaning solvent. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of the present invention will be described in detail. The dry cleaning solvent composition of the present invention is characterized by containing a fluorine-containing solvent having a boiling point of less than 40°C. Dry cleaning washing machines generally have openings with large areas to facilitate the removal and insertion of items to be washed. It is common technical knowledge in this field that the fluorine-based solvents used in such dry cleaning washing machines have a boiling point of 40°C or higher in accordance with the climate (average temperature) of Japan in order to reduce the amount of solvent carried out of the machine (volatilization of the solvent outside the machine), and it would be unthinkable for a person skilled in the art to select a fluorine-based solvent with a boiling point of less than 40°C as a dry cleaning solvent composition.

[0012] There are no limitations on the use of any fluorine-based solvent having a boiling point of less than 40° C. in the dry cleaning solvent composition of the present invention, but it is particularly preferable to use 1,1,1,4,4,4-hexafluoro-2-butene and 1-chloro-3,3,3-trifluoropropene. 1,1,1,4,4,4-Hexafluoro-2-butene is also called HFO-1336mzz. There are two types of isomers in HFO-1336mzz: (E) and (Z). The boiling point of the (E) isomer is about 7.5°C, and the boiling point of the (Z) isomer is about 33°C. Both have a global warming potential of less than 10, and an ozone depletion potential of zero. For the purposes of the present invention, either one can be used, and a mixture of them can also be used. The structure of the (Z) isomer is as follows: [ka]

[0013] 1-Chloro-3,3,3-trifluoropropene, also known as HCFO-1233zd, is a compound with a boiling point of 39°C. Its ozone depletion potential is close to zero, and its global warming potential is less than 1. It exists in (E) and (Z) forms, either of which can be used for the purposes of the present invention, and can also be used as a mixture thereof. The structure of the (Z) form is as follows: [ka]

[0014] 1,1,1,4,4,4-Hexafluoro-2-butene and 1-chloro-3,3,3-trifluoropropene can be used alone or in combination in the range of 1:99 to 99:1 (wt %).

[0015] It can also be used with other dry cleaning solvents. Examples of such dry cleaning solvents include, but are not limited to: Examples of chlorine-based solvents include perchloroethylene (tetrachloroethylene), etc. An example of a petroleum-based product is No. 5 industrial gasoline. Examples of fluorine-based solvents include 1,1,1,3,3-pentafluorobutane (HFC-365mfc), 1,1,2,2-tetrafluoroethyl 2,2,2-trifluoroethyl ether (HFE-347), and the like. There is no limitation on the mixing ratio of the dry cleaning solvent composition of the present invention to other dry cleaning solvents, and the composition of the present invention can be combined with other dry cleaning solvents in the range of 1:99 to 99:1 (wt %).

[0016] The dry cleaning solvent composition of the present invention can be used together with a surfactant generally known as soap. By using the composition together with soap, it is expected that the cleaning power will be improved. There is no particular limitation on the soap that can be used together with the dry cleaning solvent composition of the present invention. For example, Florence 365 Concentrate (Nicca Chemical Co., Ltd.), Hi-Flor Concentrate S (Genbu Co., Ltd.), and Hi-Flor NF Concentrate (Genbu Co., Ltd.) can be used. The amount of soap used in the dry cleaning solvent composition of the present invention is 0.1 to 1.0 vol %.

[0017] Depending on the purpose, chemicals such as other alcohols, hydrocarbons, ketones, ethers, esters, etc. may be added within a range that does not impair the characteristics of the present invention. Examples of alcohols include ethanol, 1-propanol, 2-propanol, etc. Examples of hydrocarbons include pentane, hexane, heptane, etc. Examples of ketones include acetone and methyl ethyl ketone. Examples of ethers include diethyl ether, etc. Examples of esters include methyl acetate and ethyl acetate, etc.

[0018] A stabilizer may be added within a range that does not impair the characteristics of the present invention. Examples of stabilizers include nitroalkanes, epoxides, phenols, and hydrocarbons. Examples of nitroalkanes include nitromethane. Examples of epoxides include propylene oxide, butylene oxide, and dioxolane. Examples of phenols include 2,6-di-tert-butyl-4-methylphenol. Examples of hydrocarbons include trimethylpentanes. EXAMPLES

[0019] The present invention will be described in more detail below by way of examples, but the present invention is not limited to these examples.

[0020] The properties of each component used in the present invention are as shown in Table 1 below.

[0021] [Table 1]

[0022] <Cleaning agent> The cleaning compositions used in the examples and comparative examples are shown below. (Composition of the Invention 1) HFO-1336 Opteon(registered trademark) SF33 manufactured by Mitsui Chemours Fluoro Products Co., Ltd. (Composition 2 of the present invention) HFO-1336 / HFE-347 HFO-1336 and HFE-347 were placed in a lidded metal can (20 L) at a ratio of 60:40 (weight %) (12.0 kg of HFO-1336 and 8.0 kg of HFE-347) and mixed by shaking and stirring. (Comparative composition 1) HFC-365 / HFE-347 HFC-365 and HFE-347 were placed in a lidded metal can (20 L) in a ratio of 60:40 (weight %) (12.0 kg of HFC-365 and 8.0 kg of HFE-347) and mixed by shaking and stirring.

[0023] <Soap> The soaps used in the examples and comparative examples are as follows: Florence 365 Concentrate (manufactured by Nicca Chemical Co., Ltd.) -High Flow Concentrate S (Genbu Co., Ltd.) - Hi-Flor NF Concentrate (Genbu Co., Ltd.)

[0024] <Soap solubility> 100 ml of the present composition 1 or 2, or comparative composition 1, was placed in a glass bottle (200 ml) with a lid, and 0.2 vol% of the soap shown in Table 2 was added and shaken to stir. The solubility was then visually confirmed, with solubility being marked as ◯ if it was soluble (no cloudiness or residual liquid) and marked as × if it was insoluble (cloudiness or residual liquid).

[0025] <Cleaning performance evaluation> The test pieces (each soiled cloth and white cloth for re-soiling evaluation) were washed according to the following procedure, and the washing rate was calculated. 1: The following soiled cloths were used as test specimens: (1) Water-soluble soiled cloth The polyester fabric was dyed with an aqueous solution of food coloring and sodium carboxymethylcellulose, air-dried, and cut into a piece measuring 5 cm x 5 cm. (2) Wet artificially soiled cloth The plate (5cm x 5cm) was purchased from Soritsu Co., Ltd. (3) White cloth for recontamination evaluation The attached white cloth for dye fastness testing conforming to JIS L 0803 was made of wool, polyester, cotton, and Toray Ecsaine, all cut to 5cm x 5cm. 2: Each contaminated cloth and the white cloth for re-contamination evaluation are left for 24 hours in an environment of 20°C and 65% relative humidity. 3: 100 ml of the present compositions 1 and 2, or comparative composition 1, was placed in a glass bottle (450 ml) with a lid, and 0.2 vol.% Hi-Flor Conc S (manufactured by Genbu Co., Ltd.) was dissolved therein. Then, 10 stainless steel balls (diameter approximately 6 mm) for stirring were added. Place each of the contaminated cloths from step 2 and a white cloth for recontamination evaluation into a 4:3 glass bottle. 5: For stirring, use a reciprocating shaker at 350 rpm and 30 mm amplitude (vertical direction) and stir at 20°C for the specified time (15 minutes). 6: After stirring, remove each soiled cloth and the white cloth for re-soiling evaluation from the glass bottle and dry at room temperature for one day and one night. 7: The reflectance of each dried soiled cloth and the white cloth for re-soiling evaluation was measured before and after washing using a color difference meter (SE7700, manufactured by Nippon Denshoku Industries Co., Ltd.). 8: Using the measured reflectance, calculate the cleaning rate using the following formula. Cleaning rate (%) = {(reflectance of soiled cloth after cleaning - reflectance of soiled cloth before cleaning) / (reflectance of white cloth - reflectance of soiled cloth before cleaning)} x 100

[0026] <Amount of each detergent composition released into the room when removing clothes> and <Indoor diffusion amount of each cleaning composition> Clothes (10 kg) were placed in a dry-cleaning machine (NFZ-1000i, manufactured by JAVUS Co., Ltd., equipped with an automatic drying time extension function and a function to suck in outside air when the door is opened) and washed using the automatic function according to the washing process described below. The concentrations of fluorinated solvents released into the room during the cleaning process and when the clothes were removed were measured using a fluorocarbon gas concentration meter (manufactured by Riken Keiki Co., Ltd., model RI-413A).

[0027] <Cleaning process> 1: Open the clothes loading port and place the clothes into the washing tank of the device. 2: Cleaning The mixture of each cleaning composition and soap is used to wash clothes to remove adhering soil. 3: Rinse Using each cleaning composition, rinse off any remaining soap and dirt from the clothes washed in step 2 above. 4: Drying (hot air) After rinsing, the clothes are dried at a drying temperature of 50°C. The vapor of each cleaning composition is recovered and reused by a recovery device (a device that cools and condenses the vapor of each cleaning composition using a cooling tube and a device that adsorbs and desorbs using activated carbon) located inside the cleaning device. 5: Cooling The clothes heated in step 4 above are cooled to room temperature. The vapor of each cleaning composition evaporated during this process is collected and reused by a recovery device (a device that cools and condenses the solvent vapor using a cooling tube and a device that adsorbs and desorbs using activated carbon) in the cleaning device. 6: Take out Open the clothes compartment and remove the clothes.

[0028] In the above process, the vapor of each detergent composition does not leak outside the device except when the clothes are removed, and the vapor of each detergent composition diffuses into the room only in step 6 above. Therefore, the amount of each detergent composition released into the room when the clothes were removed and the amount of each detergent composition diffused into the room were measured at the timing of step 6 above.

[0029] [Examples 1 and 2, Comparative Example 1] Using the compositions 1 and 2 of the present invention and the comparative composition 1, the solubility of soap, the cleaning performance, the amount of each cleaning composition released into the room when removing clothes, and the amount of each cleaning composition diffused into the room were measured. The results are shown in Table 2.

[0030] [Table 2]

[0031] Compositions 1 and 2 of the present invention and comparative composition 1 all dissolved the three types of soap well. The cleaning performance was evaluated by adding the same amount of Hi-Flor Conc S as soap to the present compositions 1 and 2 and the comparative composition 1. The present compositions 1 and 2 showed higher cleaning performance than the comparative composition for both water-soluble soiled cloth and wet artificially soiled cloth, and showed different results in terms of soil removal. The amount of detergent released when removing clothes using the compositions 1 and 2 of the present invention was lower than the working environment concentration (tolerable concentration) recommended by each solvent manufacturer. In both cases, the amount of detergent released was much lower than the amount released when the comparative composition 1 was used, and the amount of diffusion into the room of the compositions 1 and 2 of the present invention was much less than that of the comparative composition 1. This means that the exposure concentration of the detergent composition for cleaning workers is low. Since dry cleaning solvents usually have high vapor pressure (low boiling point) and are highly volatile, the amount of diffusion into the room is large and the exposure to cleaning workers is also considered to be high. Considering that the vapor pressure of HFO-1336 contained in the compositions 1 and 2 of the present invention is higher than that of HFC-365 contained in the comparative composition 1 (the boiling point of HFO-1336 is lower than that of HFC-365), the above results are unexpected.

[0032] The dry cleaning solvent composition of the present invention has good soap solubility and high cleaning power. In addition, it has zero ozone depletion potential, low global warming potential, and is environmentally friendly, and also has low volatility during use. The dry cleaning solvent composition of the present invention is a next-generation, excellent dry cleaning solvent with very little environmental impact.

Claims

1. A dry cleaning solvent composition comprising a fluorine-based solvent having a boiling point of less than 40°C.

2. 2. The dry cleaning solvent composition of claim 1, further comprising a soap.

3. 3. The dry cleaning solvent composition according to claim 1, wherein the fluorine-based solvent having a boiling point of less than 40° C. comprises either 1,1,1,4,4,4-hexafluoro-2-butene and / or 1-chloro-3,3,3-trifluoropropene.

4. The dry cleaning solvent composition according to claim 1 or 2, further comprising a fluorine-containing solvent having a boiling point of 40° C. or higher.

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