KR20220024464A - Purification method of fluorinated liquid and purification apparatus using same - Google Patents

Abstract

A method for purifying a fluorinated liquid according to an embodiment of the present invention includes performing the extraction step two or more times, wherein the extraction step is a first step of bringing the fluorinated liquid mixed with a detergent into contact with water and water contacting a second step of separating the subsequent mixed solution into two liquids, an aqueous phase located in the upper layer and a phase containing a fluorinated liquid located in the lower layer, and then collecting the liquid in the lower layer, and final extraction the total amount of water brought into contact with the liquid until the stage is about 30.0% by mass or less, the detergent is an aprotic polar solvent soluble in the fluorinated liquid, and the fluorinated liquid is a hydrofluoroether, a hydrofluoroolefin, or a mixture thereof am.

Description

Purification method of fluorinated liquid and purification apparatus using same

The present invention relates to a method for purifying a fluorinated liquid and a purification apparatus using the method.

For example, a method of manufacturing an organic EL display includes forming an organic light emitting layer by evaporating dyes of three RGB colors on a substrate, such as glass, through a metal mask. Since the metal mask is an expensive member, after cleaning the metal mask with a cleaning agent such as N-methyl-2-pyrrolidone, the metal mask is reused after performing a rinsing step using a fluorinated liquid and a drying step.

Patent Document 1 (Japanese Patent Application Laid-Open No. 2006-313753) discloses a metal mask used in a vacuum evaporation step when manufacturing a low molecular weight organic EL device using an aprotic polar solvent, such as N-methyl-2-pyrrolidone. A cleaning method in which cleaning is performed by immersion or by a jet stream using a cleaning liquid composition containing it followed by rinsing with hydrofluoroether is described.

Patent Document 2 (Japanese Patent Application Laid-Open No. H07-076787) discloses a purification apparatus for a metal cleaning agent, including a cleaning apparatus using NMP as a metal cleaning agent, and a liquid obtained by removing contaminants from an NMP cleaning liquid after cleaning A purifying device circulating to the device is described, wherein the filter material provided in the purifying device is a granular filter material containing at least polypropylene and having floatability to NMP.

Patent Document 3 (Japanese Patent Application Laid-Open No. 2008-163400) discloses that a cleaning liquid containing at least one selected from (1a) hydrocarbons, (1b) glycol ethers, and (1c) esters is stored, and a material to be cleaned is immersed. being a cleaning tank; a rinsing liquid tank in which a rinsing liquid containing at least one selected from (2a) hydrofluorocarbon and (2b) hydrofluoroether as a main component is stored, and a material to be cleaned is immersed; a vapor tank storing the rinsing liquid and generating steam of the rinsing liquid; and a purification unit having a still.

Citation list

Patent Literature

[Patent Document 1]: JP 2006-313753 A

[Patent Document 2] JP H07-076787 A

[Patent Document 3]: JP 2008-163400 A

In general, increasing the number of cleaning and rinsing operations also increases the rate of mixing of the cleaning agent into the rinse tank. As a result, the rinsing tank becomes contaminated with the cleaning agent, and therefore the rinsing liquid needs to be replaced periodically. However, since the fluorinated liquid used as the rinsing liquid is also an expensive solvent, there has been a need for a technique for efficiently collecting and reusing the fluorinated liquid from a contaminated rinsing liquid.

In recent years, regulations such as reducing environmental load have tended to be carried out in each country and, for example, in various manufacturing lines, and there has been a demand for strict drainage control measures such as reducing wastewater.

The present invention provides a method for purifying a fluorinated liquid that contributes to reducing environmental load and has excellent purification efficiency for a fluorinated liquid mixed with a cleaning agent, and a purification apparatus using the method.

According to an embodiment of the present invention, there is provided a method for purifying a fluorinated liquid, the method comprising performing an extraction step at least twice, wherein the extraction step is brought into contact with water and a fluorinated liquid mixed with a detergent. a second step of separating the mixed solution after the first step and water contacting into two liquids, an aqueous phase located in the upper layer and a phase containing a fluorinated liquid located in the lower layer, and then collecting the liquid in the lower layer wherein the total amount of water brought into contact with the final extraction step is not more than about 30.0 mass %, the detergent is an aprotic polar solvent soluble in the fluorinated liquid, and the fluorinated liquid is hydrofluoroether, hydrofluoroolefin , or a mixture thereof.

According to another embodiment of the present invention, there is provided a method for using the purified fluorinated liquid by using the above-described purification method of the fluorinated liquid as a rinsing liquid for a member used in an organic EL display manufacturing apparatus.

According to another embodiment of the present invention, there is provided an apparatus for purifying a fluorinated liquid, the apparatus comprising extraction means for performing the extraction step at least twice, wherein the extraction step is a fluorinated liquid mixed with a cleaning agent and water The mixed solution after the first step of contacting and water contacting is separated into two liquids, an aqueous phase located in the upper layer and a phase containing a fluorinated liquid located in the lower layer, and then the liquid in the lower layer is collected wherein the total amount of water brought into contact until the final extraction step is about 30.0% by mass or less, the cleaning agent is an aprotic polar solvent dissolved in the fluorinated liquid, and the fluorinated liquid is hydrofluoroether, hydro fluoroolefins, or mixtures thereof.

According to the present invention, it is possible to provide a method for purifying a fluorinated liquid that contributes to reducing the environmental load and has excellent purification efficiency for the fluorinated liquid in which a cleaning agent is mixed, and a purification apparatus using the method.

The above description should not be construed as disclosing all aspects of the invention and all advantages of the invention.

In the following, a more detailed description is provided for the purpose of illustrating representative embodiments of the present invention, but the present invention is not limited to these embodiments.

In the method for purifying a fluorinated liquid according to an embodiment of the present invention, the extraction step is performed two or more times, and the extraction step is a first step of bringing the cleaning agent into contact with the mixed fluorinated liquid and water, and the mixed solution after contacting with water a second step of separating into two liquids, an aqueous phase located in the upper layer and a phase containing a fluorinated liquid located in the lower layer, and then collecting the liquid in the lower layer, contacting until a final extraction step The total amount of water to be made is about 30.0% by mass or less, wherein the detergent used is an aprotic polar solvent that is dissolved in a fluorinated liquid, and the fluorinated liquid is a hydrofluoroether, a hydrofluoroolefin, or a mixture thereof. According to the purification method of the present invention, even if the total amount of water contacted until the final extraction step is as low as about 30.0 mass% or less, the purification efficiency of the fluorinated liquid is excellent, the amount of wastewater is small, and thus the environmental load is reduced Or it may be possible to contribute to suppression.

The cleaning agent that can be mixed in the purification method of the fluorinated liquid of the present invention is a cleaning agent used during cleaning of various members, examples of which include a cleaning agent used during cleaning of a metal mask, an anti-deposition plate, etc. in an organic EL display manufacturing apparatus. Included. The cleaning agent is not particularly limited as long as it is an aprotic polar solvent dissolved in the fluorinated liquid. Examples thereof include at least one selected from a cyclic amide-based solvent, an amine-based solvent, a glycol ether-based solvent, acetone, dimethyl sulfoxide, and dimethylformamide. These detergents have excellent cleaning action, are more soluble in water than fluorinated liquids, and are therefore suitable cleaning agents in the purification process of the present invention in which water is used to remove the cleaning agent from the fluorinated liquid. Among these, from the viewpoint of the balance of the cleaning properties of various members such as metal masks and anti-deposition plates, and solubility in fluorinated liquids and water, cyclic amide-based solvents are preferable, N-alkyl-pyrrolidone solvents; For example, solvents referred to as N-methyl-2-pyrrolidone (NMP) and N-butyl-2-pyrrolidone (NBP) or γ-lactam solvents are more preferred, and N-methyl-2-pyrrolidone ( NMP) is particularly preferred. Such aprotic polar solvents may be used alone or in combination of two or more thereof. When the above-mentioned cleaning agent is used, the fluorinated liquid can be efficiently purified by the purification method of the present invention. The cleaning agent may contain other cleaning agents in addition to the aforementioned cleaning agents within the range not inhibiting the purification efficiency of the fluorinated liquid; It is preferable that other cleaning agents are not contained from a viewpoint of purification efficiency etc.

The boiling point of the detergent is not particularly limited, but, for example, in consideration of the application of the distillation step described below, preferably about 55° C. or more, about 100° C. or more, about 120° C. or more, about 150° C. or more, about 180° C. or greater, about 200°C or greater, or about 250°C or greater. The upper limit of the boiling point of the detergent is not particularly limited, and for example, may be set to about 300°C or less, about 280°C or less, or about 260°C or less.

Examples of the fluorinated liquid that can be purified by the method for purifying the fluorinated liquid of the present invention include hydrofluoroethers, hydrofluoroolefins, or mixtures thereof. The fluorinated liquid may contain other fluorinated liquids (eg, hydrochlorofluorocarbons, hydrofluorocarbons, etc.) in addition to the above-mentioned fluorinated liquids within the range not inhibiting the purification efficiency; From the viewpoint of purification efficiency and the like, it is preferable that other fluorinated liquids are not included.

The solubility of water in the fluorinated liquid is not particularly limited. For example, from the standpoint of separation performance and purification efficiency between the aqueous phase and the phase containing the fluorinated liquid, the solubility of water at 25° C. is advantageously about 500 ppm or less, about 300 ppm or less, about 200 ppm or less, or about 150 ppm or less. The lower limit of the solubility is not particularly limited, and for example, may be set to about 10 ppm or more, about 30 ppm or more, or about 50 ppm or more. Detergents such as NMP are more readily soluble in water than fluorinated liquids. Therefore, when the solubility of water in the fluorination liquid is within this range, water is difficult to dissolve in the fluorination liquid, and therefore, when it comes into contact with water, the cleaning agent in the fluorination liquid tends to be more easily incorporated into the water. and the percentage of detergent remaining in the fluorinated liquid can be further reduced. Here, "solubility of water in a fluorinated liquid" refers to a mass ratio of water that can be dissolved in a maximum amount of water in a fluorinated liquid under an atmosphere of 25°C, and Karl Fischer Titration Method defined by JIS K 0068: 2001 (Karl Fischer Titration Method) ) (coulometric titration method) obtained by measuring at least 5 times using a micro-moisture measuring device (manufactured by Mitsubishi Chemical Analytech Co., Ltd.) is the average value.

The boiling point of the fluorinated liquid is not particularly limited, but, for example, in consideration of the application of the distillation step described below, preferably at least about 30° C., at least about 55° C., at least about 60° C., or at least about 75° C., and preferably about 150° C. or less, about 100° C. or less, or about 80° C. or less.

Among the above-mentioned fluorinated liquids, from the viewpoint of separation performance and purification efficiency of the aqueous phase and the phase containing the fluorinated liquid, the use of hydrofluoroether is preferable. Hydrofluoroethers are compounds containing oxygen atoms capable of ether bonding between the carbon atoms of the hydrofluorocarbon. The number of ether bondable oxygen atoms contained in one molecule of hydrofluoroether may be 1 or 2 or more. From the viewpoints of ease of use as a solvent, a boiling point, stability, and the like, one or two are preferable, and one is more preferable. The molecular structure of the hydrofluoroether needs to be only a chain and may be a straight chain or a branched chain, but a straight chain is preferable from the viewpoint of purification efficiency and the like.

Examples of hydrofluoroethers include segregate-type hydrofluoroethers such as C ₄ F ₉ OCH ₃ , C ₄ F ₉ OCH ₂ CH ₃ , C ₅ F ₁₁ OCH ₃ , C ₅ F ₁₁ OCH ₂ CH ₃ , C ₆ F ₁₃ OCH ₃ , C ₆ F ₁₃ OCH ₂ CH ₃ , C ₇ F ₁₅ OCH ₃ , C ₇ F ₁₅ OCH ₂ CH ₃ , C ₈ F ₁₇ OCH ₃ , C ₈ F ₁₇ OCH ₂ CH ₃ , C ₉ F ₁₉ OCH ₃ , C ₉ F ₁₉ OCH ₂ CH ₃ , C ₁₀ F ₂₁ OCH ₃ , and C ₁₀ F ₂₁ OCH ₂ CH ₃ ; and hydrofluoroethers such as CF ₃ CH ₂ OCF ₂ CF ₂ H, CF ₃ CHFOCH ₂ CF ₃ , CF ₃ CH ₂ OCF ₂ CFHCF ₃ , CHF ₂ CF ₂ CH ₂ OCF ₂ CF ₂ H, C ₃ F ₇ OC ₃ F ₆ OCFHCF ₃ , CF ₃ CF(CF ₃ )CF(OCH ₃ )CF ₂ CF ₃ , CF ₃ CF(CF ₃ )CF(OC ₂ H ₅ )CF ₂ CF ₃ , CF ₂ (OCH ₂ CF ₃ ) CF ₂ H, CF ₂ (OCH ₂ CF ₃ )CFHCF ₃ , CF ₂ (OCH ₂ CF ₂ CF ₂ H)CF ₂ H, and CF ₂ (OCH ₂ CF ₂ CF ₂ H)CFHCF ₃ . Such hydrofluoroethers may be used alone or in combination of two or more thereof.

Among them, the isolated hydrofluoroether has a low solubility in water, and when it comes into contact with water, the rate of dissolution in the aqueous phase can be reduced compared to other hydrofluoroethers or hydrofluoroolefins, whereby It is thus easy to separate the aqueous phase from the phase containing the fluorinated liquid. As a result, the separated aqueous phase is less likely to be contaminated with a fluorinated liquid, and thus, for example, can be subjected to relatively stringent emission regulations. Among the isolated hydrofluoroethers, C ₄ F ₉ OCH ₃ or C ₄ F ₉ OCH ₂ CH ₃ is more preferred. Herein, "isolated" refers to a structure in which one side is fully fluorinated and the other side is composed of carbon and hydrogen, and an ether bond is interposed therebetween.

Hydrofluoroolefins are intended to be compounds in which one or more hydrogen atoms in the olefin have been replaced by a fluorine atom. The number of fluorine atoms contained in the hydrofluoroolefin is not particularly limited and may be 1 or more or 2 or more, and 10 or less or 6 or less. The hydrofluoroolefin may be of either type E (trans type) or type Z (cis type). The hydrofluoroolefin may be a hydrochlorofluoroolefin. Hydrochlorofluoroolefins are intended to be compounds in which one or more hydrogen atoms in the olefin are replaced by fluorine atoms and one or two or more other hydrogen atoms in the olefin are replaced by chlorine atoms. The number of chlorine atoms in the hydrochlorofluoroolefin is not particularly limited and may be 1 or more, and 5 or less or 3 or less.

Examples of hydrofluoroolefins having no chlorine atoms include CF ₃ -CH=CH ₂ , CF ₃ -CF=CH ₂ , CHF ₂ -CH=CHF, CHF ₂ -CF=CH ₂ , CH ₂ F-CH=CF ₂ , CH ₂ F-CF=CHF, CH ₃ -CF=CF ₂ , CF ₃ -CH=CH-CF ₃ , CF ₃ -CH=CF-CH ₃ , CF ₃ -CF=CH-CH ₃ , CF ₃ -CH=CH-CH ₂ F, CHF ₂ -CF=CF-CH ₃ , CHF ₂ -CF=CH-CH ₂ F, CHF ₂ -CH=CF-CH ₂ F, CHF ₂ -CH=CH-CHF ₂ , CH ₂ F-CF=CF-CH ₂ F, CH ₂ F-CH=CH-CF ₃ , CH ₂ F-CF=CH-CHF ₂ , CF ₃ -CH ₂ -CF=CH ₂ , CF ₃ -CHF -CH=CH ₂ , CF ₃ -CH ₂ -CH=CHF, CHF ₂ -CF ₂ -CH=CH ₂ , CHF ₂ -CHF-CF=CH ₂ , CHF ₂ -CHF-CH=CHF, CH ₂ F- CF ₂ -CF=CH ₂ , CH ₂ F-CF ₂ -CH=CHF, CH ₂ F-CHF-CF=CHF, CH ₂ F-CHF-CF=CF ₂ , CH ₂ F-CH ₂ -CF=CF ₂ , CH ₃ -CF ₂ -CF=CHF, and CH ₃ -CF ₂ -CH=CF ₂ . Examples of hydrofluoroolefins having chlorine atoms (ie hydrochlorofluoroolefins) include CF ₃ -CH=CHCl, CHF ₂ -CF=CHCl, CHF ₂ -CH=CFCl, CHF ₂ -CCl=CHF, CH ₂ F-CCl=CF ₂ , CHFCl-CF=CHF, CH ₂ Cl-CF=CF ₂ , and CF ₃ -CCl=CH ₂ . A particularly preferred hydrofluoroolefin having chlorine atoms is CF ₃ -CH=CHCl. Hydrofluoroolefins (including hydrochlorofluoroolefins) may be used alone or in combination of two or more thereof.

The water used in the purification method of the fluorinated liquid of the present invention is not particularly limited, and for example, tap water, distilled water, ion-exchanged water, etc. may be used.

In the method for purifying a fluorinated liquid of the present invention, the extraction step is performed two or more times, and the extraction step is a first step of bringing the cleaning agent into contact with the mixed fluorinated liquid and water, and the mixed solution after contact with water is divided into two liquids, that is, a second step of separating an aqueous phase located in the upper layer and a phase containing a fluorinated liquid located in the lower layer, and then collecting the liquid in the lower layer. The upper limit of the number of times the extraction step is performed is not particularly limited, but from the viewpoint of simplifying the purification process, it is advantageous to have, for example, 5 times or less, 4 times or less, or 3 times or less.

The method of contacting the fluorinated liquid mixed with the cleaning agent with water in the first step is not particularly limited, and, for example, the following methods (1) to (7) may be used alone or in combination of two or more thereof. and may be performed by combining some of the methods (1) to (7) as needed. For example, as described in (3), (6), or (7), the physical stirring method using vibration, a stirrer, etc., the stirring method using air, and the stirring method using ultrasonic waves etc. are (1) or It can be applied to the method of (2).

(1) A method in which a fluorinated liquid mixed with a cleaning agent is dripped onto a container filled with water.

(2) A method of adding water to a vessel containing a fluorinated liquid mixed with a detergent from below.

(3) A method of physically stirring a container containing a mixed solution of a cleaning agent, a fluorinated liquid, and water by using a stirrer, stirring blade, or the like.

(4) In a situation in which the mixed solution is already separated into two layers in a container containing a mixed solution of a cleaning agent, a fluorinated liquid and water, the upper layer and the lower layer are connected to each other by a tube or the like, and the upper layer by gravity or a pump How the liquid moves to the lower layer.

(5) In a situation in which the mixed solution is already separated into two layers in a container containing a mixed solution of a cleaning agent, a fluorinated liquid and water, the upper layer and the lower layer are connected to each other by a tube or the like, and the lower layer by gravity or a pump How the liquid moves to the upper layer.

(6) In a situation where the mixed solution has already been separated into two layers in a container containing a mixed solution of a cleaning agent, a fluorinated liquid and water, a gas, such as air, is blown into the container and bubbled to mix the mixed solution, by gravity or A method in which the lower layer liquid is moved to the upper layer by means of a pump.

(7) In the situation where the mixed solution has already been separated into two layers in a container containing a mixed solution of a cleaning agent, a fluorinated liquid and water, ultrasonic waves are applied to the container to mix the mixed solution, and the lower layer liquid by gravity or a pump is moved to the upper floor.

The amount of water contacted in the first step may be the same or different from each other in each extraction step. For example, if the extraction step is performed three times, a total of 3.0 g of water may be added in 1.0 g increments to contact the fluorinated liquid mixed with the detergent, alternatively 1.5 g of water may be added in the first round, 1.0 g can be added in the second batch and 1.5 g in the third batch.

According to the method for purifying a fluorinated liquid of the present invention, even if the amount of water contacted in the first step performed first is low and the total amount of water contacted up to the final extraction step is about 30.0 mass% or less, the extraction step is performed two or more times. Purification efficiency can be achieved. The amount of water contacted in the first step performed first may be about 20.0 mass% or less, about 19.0 mass% or less, or about 18.0 mass% or less, and about 3.0 mass% or more, about 4.0 mass% or more, or about 5.0 mass% may be more than Here, the "amount of water brought into contact in the first step performed first" is a value calculated as a percentage of the mass of water added to the mass of the cleaning agent contained in the fluorinated liquid and the mass of water added in the first step performed first means Furthermore, the mass of the cleaning agent contained in the fluorinated liquid at the beginning of the first step can be determined by a quantitative analytical method using a calibration curve representing the correlation of the concentration of the cleaning agent in the fluorinated liquid, prepared in advance by a gas chromatography analyzer. can

The temperature and time when the fluorinated liquid mixed with the cleaning agent and water are contacted are not particularly limited because they may vary depending on the required performance of the purified fluorinated liquid, the scale size, the contact method, and the like. For example, the temperature can be at least about 20°C, at least about 23°C, or at least about 25°C, and at most about 40°C, at most about 35°C, or at most about 30°C, and the contact time being at least about 30 seconds, at least about It may be set to 1 minute or more, or about 5 minutes or more, and may be about 1 day or less, about 10 hours or less, about 1 hour or less, or about 30 minutes or less.

The second step in the extraction step separates the mixed solution after water contact into two liquids, an aqueous phase located in the upper layer and a phase containing a fluorinated liquid located in the lower layer, and then collects the liquid in the lower layer including the steps of Separation of the upper layer and the lower layer into two liquids can be achieved, for example, by passing through a step of allowing a mixed solution containing a cleaning agent and a fluorinated liquid to stand still.

The lower layer liquid may be collected directly from below the container containing the upper layer liquid and the lower layer liquid through a tube or the like, or the upper layer liquid may be collected from above the container, and then the lower layer liquid may be collected, a tube or the like It can be stretched and aspirated from the top of the container to near the bottom of the container.

The total amount of water contacted until the final extraction step is about 30.0 mass % or less, for example, taking into account the reduction in the amount of wastewater and the balance of purification efficiency, the total amount is about 29.0 mass % or less, about 28.0 mass % or less, or about 27.0 mass % It is advantageously no more than about 25.0 mass%, about 23.0 mass% or less, or about 20.0 mass% or less, and advantageously about 5.0 mass% or more, about 7.0 mass% or more, or about 9.0 mass% or more. Here, the "total amount of water contacted until the final extraction step" means a value calculated as a percentage of the total amount of water added to the mass of the cleaning agent contained in the fluorinated liquid at the beginning of the first step and the total amount of water added.

The purity of the fluorinated liquid purified through the purification method of the fluorinated liquid of the present invention may be about 95.0% or more, about 96.0% or more, about 97.0% or more, or about 98.0% or more. The upper limit of the purity of the fluorinated liquid is not particularly limited, and may be set, for example, to less than about 100%, about 99.9% or less, or about 99.8% or less.

The method for purifying a fluorinated liquid of the present invention can be applied as needed by using one or a combination of two or more of a heating step, a distillation step (eg, boiling distillation step, vacuum distillation step, etc.), a cooling separation step, and the like.

If it is desired to increase the purity of the fluorinated liquid, the purification method of the present invention may further comprise a distillation step of distilling the bottom layer liquid collected through the final extraction step. In the related art, distillation means have generally been used for the purification of fluorinated liquids, but when the fluorinated liquids are purified using the distillation means alone, since the amount of fluorinated liquids that can be recovered is extremely low, Most of the fluorinated liquid should be substantially discarded. On the other hand, when the distillation step is combined with the purification method of the fluorinated liquid of the present invention, the recovery amount of the fluorinated liquid can be greatly improved compared to the purification method using the distillation means alone.

The distillation temperature in the distillation step is not limited to the following, and may be, for example, about 70°C or higher, about 72°C or higher, or about 75°C or higher, and about 100°C or lower, about 95°C or lower, or about 90°C or lower. can

In some embodiments, the purification method of the present invention may not apply an additional distillation step or heating step. A purification method that does not include such steps can complete the purification at room temperature, thereby increasing energy efficiency and eliminating the need for additional work. Therefore, from the viewpoint of reducing the environmental load, it is advantageous not to use a distillation step or a heating step.

A fluorinated liquid purification apparatus according to an embodiment of the present invention includes extraction means for performing an extraction step performed two or more times, wherein the extraction step is a first step of bringing the cleaning agent into contact with the mixed fluorinated liquid and water and a second step of separating into two phases, an aqueous phase located in the upper layer and a phase containing a fluorinated liquid located in the lower layer, and then collecting the liquid in the lower layer, the liquid until the final extraction step The total amount of water that comes into contact with is about 30.0% by mass or less, wherein the detergent used is an aprotic polar solvent that is soluble in a fluorinated liquid, and the fluorinated liquid is a hydrofluoroether, a hydrofluoroolefin, or a mixture thereof. am. Examples of the cleaning agent, fluorinated liquid, and water that can be used in such a purification apparatus may be the same as those used in the purification method described above. In addition, such a purification apparatus can similarly exhibit the effects described in the purification method described above.

The extraction means in the fluorinated liquid purification apparatus of the present invention is not particularly limited as long as the extraction means can perform an extraction step comprising the first and second steps of the above-described method for purifying a fluorinated liquid. The material, capacity, shape, amount, location, etc. of a container (referred to in some cases as a "tank" or the like) for storing a mixed solution containing, for example, a cleaning agent, a fluorinated liquid, and water used in the extraction means, etc. Silver may be appropriately selected according to the purpose of the device or the usage environment.

The fluorinated liquid purification apparatus of the present invention is a means capable of performing any steps such as a heating step, a distillation step (eg, boiling distillation step, vacuum distillation step, etc.), a cooling separation step, etc. in the above-described method for purifying a fluorinated liquid can be selectively applied. For example, the material, capacity, shape, amount, location, etc. of the container for storing the lower layer liquid used in the distillation step may be appropriately selected according to the purpose of the apparatus or the use environment. Various means such as heating means, distillation means, cooling separation means and the like may be applied to the fluorinated liquid purification apparatus alone or in combination of two or more thereof.

If it is desired to increase the purity of the fluorinated liquid, the purification apparatus of the present invention may further comprise distillation means for distilling the lower layer liquid collected through the extraction means. The distillation means may use known devices, which are, for example, a distillation port for storing and heating the collected lower bed liquid, and a chiller connected in communication with the distillation port for condensing and liquefying the vapor of the lower bed liquid. ) is included.

In some embodiments, the purification apparatus of the present invention may not apply additional distillation means or heating means. A refining apparatus that does not accommodate such means may complete refining at ambient temperature, thereby increasing energy efficiency and eliminating the need for additional work. Therefore, it is advantageous not to use distillation means or heating means from the viewpoint of reducing the environmental load.

The method and apparatus for purifying a fluorinated liquid of the present invention can be used as appropriate on-line or off-line in various production lines. In the online case, when the purification method and purification apparatus of the fluorinated liquid of the present invention are used, they may be suitably configured so that the purified fluorinated liquid can be reused, for example, in a cleaning step or in a rinsing step. When they are used offline, the fluorinated liquid used in a production line such as a cleaning step or a rinsing step of an organic EL display can be purified in another line and used again in a production line of an organic EL display; On the other hand, the purified fluorinated liquid can be reused for purposes other than the above use, for example as a cleaning liquid or rinsing liquid for printed wiring boards.

The fluorinated liquid purified using the purification method and purification apparatus of the fluorinated liquid of the present invention is not limited to the following, for example, it is used in an organic EL display manufacturing apparatus, and a metal mask exposed to cleaning and rinsing operations And in addition to rinsing liquid for various members such as anti-deposition plates, it can be used as a cleaning liquid or rinsing liquid for various electronic parts, precision parts, metal parts, printed wiring boards, and the like. Here, the "anti-deposition plate" refers to a member disposed inside a vacuum chamber of a vacuum evaporation apparatus used in the manufacture of an organic EL display, and is an evaporation source of red (R), green (G), and blue (B) It is a member that can be removed and cleaned to prevent contamination of the vacuum chamber from the three colors of The use of the rinsing liquid is not limited to direct use as a liquid, for example, rinsing and rinsing off a deposited cleaning agent or the like by immersing the material to be rinsed in the rinsing liquid, and evaporating the rinsing liquid onto the surface to be rinsed and cleaned. This includes use in the case of rinsing off a cleaning agent or the like by adhering the vaporized gas to it.

Example

Specific embodiments of the present invention will be illustrated in the following examples, but the present invention is not limited to these embodiments.

Products and the like used in this example are shown in Table 1 below.

[Table 1]

The purity of the fluorinated liquid was assessed by gas chromatography using a 7890 A manufactured by Agilent Technologies. The measurement conditions of the gas chromatography method are as follows:

Column Type: HP-1301

Column length: 60 m

Column temperature: 260°C

Type of carrier gas: helium gas

Flow rate of carrier gas: 205 mL/min

Sample injection volume: 1 μL

Example 1

100 g of Novec ^™ 7100 (fluorinated liquid) and 10 g of NMP (cleaning agent) were added to the plastic bottle. 0.2 g of distilled water was added to the mixed solution and shaken for 15 minutes on a mechanical shaker. Then, the resulting mixed solution is allowed to separate into two layers, an upper layer (aqueous phase) and a lower layer (phase containing a fluorinated liquid), and an upper layer (aqueous phase) floating on the surface using a dropper The top layer was removed from the plastic bottle by collecting (first extraction step). A microsyringe was used to collect a sample for purity determination from the lower layer liquid, and the purity of Novec ^TM 7100 in the lower layer liquid was measured. A series of operations from addition of distilled water to measurement of purity was performed a total of 4 times, and the results are shown in Table 2. Here, after the second round, addition of 0.2 g of distilled water was performed on the lower layer liquid obtained by removing the upper layer (aqueous phase). Moreover, in Table 2, "amount of water after contact with water (mass %)" is a value calculated as a percentage of the total addition amount of water and the total amount of water added to the initial blending amount (10 g) of the detergent (NMP).

<Examples 2 to 5 and Comparative Examples 1 and 2>

The purity of the fluorinated liquid was measured in the same manner as in Example 1, except that the addition amount of distilled water was changed to the amount shown in Table 2. Note that the extraction step after the fourth time in Example 4 and the third or subsequent extraction step in Example 5 were not performed because the amount of water after contacting with water exceeded 30.0 mass %. Moreover, in Comparative Example 1, in the second extraction step, the amount of water after contacting with water already exceeded 30.0 mass % in the first extraction step in Comparative Example 2, and the subsequent extraction step was not performed.

[Table 2]

It will be apparent to those skilled in the art that various modifications may be made to the above-described embodiments and examples without departing from the basic principles of the invention. Moreover, it will be apparent to those skilled in the art that various improvements and modifications of the present invention may be made without departing from the spirit and scope of the present invention.

Claims (11)

A method for purifying a fluorinated liquid, comprising:
performing the extraction step at least twice, wherein the extraction step is a first step of bringing the cleaning agent into contact with the mixed fluorinated liquid and water, and the mixed solution after contacting the water with two liquids, that is, an aqueous solution located in the upper layer a second step of separating into a phase containing a fluorinated liquid located in the upper and lower layers, followed by collecting the liquid in the lower layer;
the total amount of water brought into contact until the final extraction step is about 30.0 mass % or less,
The detergent is an aprotic polar solvent soluble in a fluorinated liquid,
wherein the fluorinated liquid is a hydrofluoroether, a hydrofluoroolefin, or a mixture thereof. The method according to claim 1, wherein the amount of water contacted in the first step performed first is 3.0 to 20.0 mass%. The purification method according to claim 1 or 2, wherein the number of times the extraction step is performed is 5 times or less. 4. The solvent according to any one of claims 1 to 3, wherein the aprotic polar solvent is at least selected from cyclic amide solvents, amine solvents, glycol ether solvents, acetone, dimethyl sulfoxide, and dimethylformamide. One, the purification method. 5. The method according to any one of claims 1 to 4, wherein the solubility of water in the fluorinated liquid is 500 ppm or less. 6 . The method according to claim 1 , further comprising distilling the bottom layer liquid collected through the final extraction step. The purification method according to any one of claims 1 to 6, wherein the purity of the fluorinated liquid purified through the purification method is at least 95.0%. A method for using a fluorinated liquid purified using the purification method according to any one of claims 1 to 7 as a rinsing liquid for a member used in an organic EL display manufacturing apparatus. The method of claim 8 , wherein the member is a metal mask or an anti-deposition plate. A fluorinated liquid purification apparatus comprising:
an extraction means for performing the extraction step at least twice, wherein the extraction step is a first step of bringing the cleaning agent into contact with the mixed fluorinated liquid and water, and the mixed solution after contacting the water with the two liquids, that is, located in the upper layer. a second step of separating into an aqueous phase and a phase containing a fluorinated liquid located in the lower layer, followed by collecting the liquid in the lower layer;
the total amount of water brought into contact until the final extraction step is about 30.0 mass % or less,
The detergent is an aprotic polar solvent soluble in a fluorinated liquid,
wherein the fluorinated liquid is a hydrofluoroether, a hydrofluoroolefin, or a mixture thereof. 11. The apparatus of claim 10, further comprising means for distilling the liquid in the lower layer collected via the extraction means.