JPWO2019013155A1 - Filter unit, purification device, manufacturing device, and chemical liquid - Google Patents

Abstract

An object of the present invention is to provide a filter unit used for purification to obtain a chemical liquid having excellent defect suppressing performance. Another object is to provide a refining device, a manufacturing device, and a chemical solution. The filter unit of the present invention comprises a filter material containing a first polymer having a multidentate substituent, which is independently arranged in a pipeline to which a substance to be purified is supplied. A filter material containing a first housing containing one filter and a second polymer having at least one bond selected from the group consisting of an amide bond, an imide bond, and an ester bond, and having a pore diameter of 50 nm or less. And a second housing in which a second filter having the above is stored.

Description

The present invention relates to a filter unit, a refining device, a manufacturing device, and a chemical liquid.

In manufacturing a semiconductor device, a chemical solution containing a solvent (typically an organic solvent) is used. In recent years, it has been required to further reduce the impurities contained in the above chemicals. Further, the manufacturing of semiconductor devices with a node of 10 nm or less is being studied, and the above requirements are further increasing.

Patent Document 1 discloses a filtering material using a polymer compound obtained by polymerizing a compound containing an imino group or a derivative thereof as a filtering material, wherein the compound is a hydroxyl group, a thiol group, a carboxy group, or a sulfonic acid. Filter materials having groups, nitro groups, or phosphate groups are described.
Further, Patent Document 2 describes a method for producing a composition for forming a coating film for lithography, which uses a film or porous material having a sulfonic acid group and/or a carboxy group bonded thereto and a filter.

JP, 2016-182554, A JP, 2016-206500, A

The inventors of the present invention refine a chemical liquid using a filter unit including a filter formed by using the filtering material described in Patent Document 1 and Patent Document 2, and suppress the defect by using the purified chemical liquid. When we examined the performance, we found that there was room for improvement.

Therefore, it is an object of the present invention to provide a filter unit used for purification for obtaining a chemical liquid having an excellent defect suppressing performance. Moreover, this invention also makes it a subject to provide a refining apparatus, a manufacturing apparatus, and a chemical|medical solution.

As a result of intensive studies to achieve the above-mentioned object, the present inventors have found that the above-mentioned object can be achieved by the following configuration.

[1] A first filter provided with a filter medium containing a first polymer having a multidentate substituent, which is independently arranged, is housed in a pipeline to which a substance to be purified is supplied. And a second polymer having at least one bond selected from the group consisting of an amide bond, an imide bond, and an ester bond, and a filter material having a pore diameter of 50 nm or less. And a second housing in which the two filters are housed.
[2] The filter unit according to [1], wherein the second polymer is nylon.
[3] The filter unit according to [1] or [2], in which the first housing is arranged on the primary side and the second housing is arranged on the secondary side.
[4] The filter unit according to any one of [1] to [3], wherein the chelate stability constant of the substituent satisfies at least one requirement selected from the group consisting of the following (A) to (E). .. (A) more than 4.5 for Al ³⁺ ions (B) more than 8.0 for Fe ³⁺ ions (C) more than 4.5 for Ti ³⁺ ions (D) for Na ⁺ ions >3.0 for (E)K ⁺ ions [5] Substituent derived from at least one compound selected from the group consisting of formulas (1) to (3) described below. The filter unit according to any one of [1] to [4], which is the basis of [1].
[6] The filter unit according to any one of [1] to [4], wherein the substituent has a chelate ring formed by combining with a metal atom and has 5 or more ring members.
[7] The filter unit according to any one of [1] to [6], wherein the chelate stability constant of the substituent satisfies at least one requirement selected from the group consisting of the following (F) to (J). ..
(F) is 6.0 to 20 for Al ³⁺ ions, and is more than 8.0 for (G)Fe ³⁺ ions, and is 6.0 or less for 20 or less (H)Ti ³⁺ ions. It is 6.0 to 20 for certain (I)Na ⁺ ions and 6.0 to 20 for (J)K ⁺ ions.
[8] The filter unit according to any one of [1] to [7], which is used for purifying a chemical liquid for semiconductor production.
[9] The filter unit according to any one of [1] to [8], wherein the first polymer having a multidentate coordinating group has a unit represented by the formula (P-1) described below. ..
[10] The filter unit according to any one of [1] to [9], wherein the first filter satisfies requirement 1 in the following test. Test: Under the condition that the mass ratio of the mass of the first filter to the mass of the test solvent containing 99.99 mass% or more of isopropanol is 1.0 when the liquid temperature of the test solvent is 25° C., One filter is immersed in a test solvent having a liquid temperature of 25° C. for 48 hours. Requirement 1: When one kind of organic impurities is contained in the test solvent after immersion, the amount of increase of one kind of organic impurities before and after the immersion is 1000 mass ppm or less, and two or more kinds in the test solvent after immersion. When an organic impurity is contained, the total amount of increase of two or more kinds of organic impurities before and after immersion is 1000 mass ppm or less.
[11] The filter unit according to any one of [1] to [10], wherein the first filter satisfies requirement 2 in the following test. Test: Under the condition that the mass ratio of the mass of the first filter to the mass of the test solvent containing 99.99 mass% or more of isopropanol is 1.0 when the liquid temperature of the test solvent is 25° C., One filter is immersed in a test solvent having a liquid temperature of 25° C. for 48 hours. Requirement 2: When one kind of metal ion is contained in the test solvent after immersion, the amount of increase of one kind of metal ion before and after immersion is 100 mass ppm or less, and two or more kinds in the test solvent after immersion. When metal ions are contained, the total amount of increase before and after the immersion of two or more metal ions is 100 mass ppm or less.
[12] The filter unit according to any one of [1] to [11], wherein the first filter satisfies requirement 3 in the following test. Test: Under the condition that the mass ratio of the mass of the first filter to the mass of the test solvent containing 99.99 mass% or more of isopropanol is 1.0 when the liquid temperature of the test solvent is 25° C., One filter is immersed in a test solvent having a liquid temperature of 25° C. for 48 hours. Requirement 3: When one kind of metal particles is contained in the test solvent after the immersion, the increase amount of one kind of the metal particles before and after the immersion is 100 mass ppm or less, and two or more kinds in the test solvent after the immersion. When the metal particles are contained, the total amount of increase before and after the immersion of two or more kinds of metal particles is 100 mass ppm or less.
[13] The filter unit according to any one of [1] to [12], wherein the filter medium included in the first filter has a pore size of 10 to 100 nm.
[14] The filter unit according to any one of [1] to [13], wherein the second filter satisfies requirement 4 in the following test. Test: The mass ratio of the mass of the second filter to the mass of the test solvent containing 99.99 mass% or more of isopropanol is 1.0 when the liquid temperature of the test solvent is 25°C. The two filters are immersed in a test solvent having a liquid temperature of 25° C. for 48 hours. Requirement 4: When one kind of organic impurities is contained in the test solvent after the immersion, the increase amount of one kind of the organic impurities before and after the immersion is 1000 mass ppm or less, and the test solvent after the immersion contains two or more kinds. When an organic impurity is contained, the total amount of increase of two or more kinds of organic impurities before and after immersion is 1000 mass ppm or less.
[15] The filter unit according to any one of [1] to [14], wherein the second filter satisfies requirement 5 in the following test. Test: The mass ratio of the mass of the second filter to the mass of the test solvent containing 99.99 mass% or more of isopropanol is 1.0 when the liquid temperature of the test solvent is 25°C. The two filters are immersed in a test solvent having a liquid temperature of 25° C. for 48 hours. Requirement 5: When one kind of metal ion is contained in the test solvent after immersion, the amount of increase of one kind of metal ion before and after immersion is 100 mass ppm or less, and two or more kinds in the test solvent after immersion. When metal ions are contained, the total amount of increase before and after the immersion of two or more metal ions is 100 mass ppm or less.
[16] The filter unit according to any one of [1] to [15], wherein the second filter satisfies requirement 6 in the following test. Test: The mass ratio of the mass of the second filter to the mass of the test solvent containing 99.99 mass% or more of isopropanol is 1.0 when the liquid temperature of the test solvent is 25°C. The two filters are immersed in a test solvent having a liquid temperature of 25° C. for 48 hours. Requirement 6: When one kind of metal particles is contained in the test solvent after immersion, the amount of increase of one kind of metal particles before and after immersion is 100 mass ppm or less, and two or more kinds in the test solvent after immersion. When the metal particles are contained, the total amount of increase before and after the immersion of two or more kinds of metal particles is 100 mass ppm or less.
[17] The filter unit according to any one of [1] to [16], wherein the filter material included in the second filter has a pore size of 1.0 to 15 nm.
[18] A third housing further including a filter medium in which at least one selected from the group consisting of a material and a pore size is different from both the filter medium included in the first filter and the filter medium included in the second filter. The filter unit according to any one of [1] to [17].
[19] The pore size of the filter medium included in the third filter is larger than the pore size of the filter medium included in the first filter, and the third housing is arranged further on the primary side than the first housing. Filter unit.
[20] The first polymer having a polydentate substituent is nylon having a polydentate substituent, polyethylene having a polydentate substituent, and polydentate substitution. The filter unit according to any one of [1] to [19], which is at least one selected from the group consisting of a poly(meth)acrylate having a group and a polyfluorocarbon having a polydentate substituent. ..
[21] A chemical liquid refining device comprising the filter unit according to any one of [1] to [20].
[22] An apparatus for producing a chemical liquid, which comprises the filter unit according to any one of [1] to [21].
[23] A chemical solution containing an organic solvent and purified using the filter unit according to any one of [1] to [22], wherein the organic solvent is propylene glycol monomethyl ether, propylene glycol monoethyl ether, Propylene glycol monopropyl ether, propylene glycol monomethyl ether acetate, ethyl lactate, methyl methoxypropionate, cyclopentanone, cyclohexanone, γ-butyrolactone, diisoamyl ether, butyl acetate, isoamyl acetate, isopropanol, 4-methyl-2-pentanol , Dimethyl sulfoxide, n-methyl-2-pyrrolidone, diethylene glycol, ethylene glycol, dipropylene glycol, propylene glycol, ethylene carbonate, propylene carbonate, sulfolane, cycloheptanone, and at least one selected from the group consisting of 2-heptanone. The seed, the drug solution.

According to the present invention, it is possible to provide a filter unit used for purification for obtaining a chemical liquid having excellent defect suppressing performance.
Further, according to the present invention, it is possible to provide a refining device, a manufacturing device, and a chemical solution.

It is the partially broken perspective view of the typical filter with which a filter unit is equipped. It is a perspective view of the typical housing with which a filter unit is provided. It is a fragmentary sectional view of the typical housing with which a filter unit is provided. It is a schematic diagram of the filter unit which concerns on embodiment of this invention. It is a schematic diagram of the filter unit which concerns on other embodiment of this invention. It is a schematic diagram of the refining device which concerns on embodiment of this invention. It is a schematic diagram of the purification apparatus which concerns on other embodiment of this invention. It is a schematic diagram of the manufacturing apparatus which concerns on embodiment of this invention.

Hereinafter, the present invention will be described in detail.
The description of the constituent elements described below may be made based on a representative embodiment of the present invention, but the present invention is not limited to such an embodiment.
In addition, in this specification, the numerical range represented using "-" means the range which includes the numerical value described before and after "-" as a lower limit and an upper limit.
Further, in the present invention, the term “preparation” includes not only the preparation or preparation of a specific material but also the procurement of a predetermined product by purchase or the like.
Further, in the present invention, “ppm” means “parts-per-million (10 ⁻⁶ )”, “ppb” means “parts-per-billion (10 ⁻⁹ )”, and “ppt” means “Parts-per-trillion (10 ⁻¹² )” means “ppq” means “parts-per-quadrillion (10 ⁻¹⁵ )”.
Further, in the present invention, 1 Å (angstrom) corresponds to 0.1 nm.
In addition, in the notation of the group (atom group) in the present invention, notation that does not indicate substitution and non-substitution includes not only those having no substituent but also those having a substituent within a range not impairing the effect of the present invention. Includes. For example, the “hydrocarbon group” includes not only a hydrocarbon group having no substituent (unsubstituted hydrocarbon group) but also a hydrocarbon group having a substituent (substituted hydrocarbon group). .. This has the same meaning for each compound.
Further, the “radiation” in the present invention means, for example, deep ultraviolet rays, extreme ultraviolet rays (EUV; Extreme ultraviolet rays), X-rays, electron beams, or the like. In the present invention, light means actinic rays or radiation. Unless otherwise specified, the term "exposure" in the present invention includes not only exposure with deep ultraviolet rays, X-rays, EUV and the like, but also drawing with particle beams such as electron beams and ion beams.

[Filter unit]
The filter unit according to the first embodiment of the present invention has a first housing and a second housing which are independently arranged in a pipe line to which a substance to be purified is supplied. The first housing accommodates a first filter including a filter medium containing a first polymer having a polydentate substituent. The second housing contains a second polymer having at least one bond selected from the group consisting of an amide bond, an imide bond, and an ester bond, and is provided with a filter medium having a pore diameter of 50 nm or less. The filter is stored.

A filter unit according to the first embodiment of the present invention will be described with reference to FIGS. The filter unit described below is an example, and the present invention is not limited to this.

FIG. 1 is a partially cutaway perspective view of a typical filter 10 included in a filter unit according to a first embodiment of the present invention. In the filter 10, a cylindrical core 12 that supports the filter 10 is arranged so as to contact the inside of the filter 11. The cylindrical core 12 is formed in a mesh shape so that liquid can easily pass therethrough. The filter material 11 and the core 12 are concentric. Caps 13 that prevent liquid from entering from the upper portions of the respective members are arranged on the upper portions of the cylindrical filter medium 11 and the core 12 so as to cover the end portions of the respective members. Further, a liquid outlet 14 for taking out the liquid from the inside of the core 12 is arranged below the cylindrical filter medium 11 and the core 12.

The liquid (substance to be purified) that flows into the filter 10 is blocked by the cap 13 and therefore does not directly flow into the inside of the core 12 but flows from the outer surface of the filter medium 11. The liquid flowing in from the outer surface passes through the filter medium 11 and the core 12, flows into the inside of the core 12, and flows out of the filter 10 from the liquid outlet 14. The inflow direction of the substance to be purified is not limited to the above, and is a form in which it flows in from the liquid outlet 14 side, passes from the inside of the core 12, passes through the core 12, passes through the filter material 11, and flows out from the outside surface. May be.

In FIG. 1, the filter 10 has a filter material 11 and a core 12 arranged in order from the outer surface. The filter according to the embodiment of the present invention is not limited to this, and in order to protect the filter medium 11, a cylindrical protector may be arranged outside the filter medium 11 so as to cover the filter medium 11. .. The cylindrical protector is preferably formed in a mesh shape like the core 12.

FIG. 2 is a perspective view of a typical housing 20 included in the filter unit according to the first embodiment of the present invention, and FIG. 3 is a partial cross-sectional view of the housing. The housing 20 is composed of a lid 21 and a body 22, and the lid 21 and the body 22 can be fitted to each other. When the lid 21 and the body 22 are fitted with each other, a cavity L is formed inside, and the cavity 10 can accommodate the filter 10.

The housing 20 has a liquid inlet 23 and a liquid outlet 24, and the liquid outlet 14 of the filter 10 and the liquid outlet 24 of the housing are connected by an internal conduit 25 provided inside the lid 21. There is. The flow of the product to be purified is indicated by F ₁ . The substance to be purified that has flowed in from the liquid inflow port 23 flows into the inside of the barrel 22 through the internal pipe line 26 provided inside the lid 21, passes through the filter material and the core from the outer surface of the filter 10. It flows inside the core and is purified in the process.
The purified liquid flowing into the inside of the core is taken out of the housing 20 from the liquid outlet of the filter 10 through the internal conduit 25 and the liquid outlet 24 (according to the flow indicated by F ₂ in FIG. 3). ). The product to be purified may flow in the opposite direction. That is, the substance to be purified, which has flowed in from the liquid outlet 24 in the direction opposite to F ₂ , flows in from the liquid outlet of the filter 10, passes through the filter medium, and flows from the outside of the filter 10 to the F through the internal conduit 26. _It may be taken out in the direction opposite to ₁ .

2 and 3, the liquid inlet 23 and the liquid outlet 24 are arranged in the lid 21 of the housing 20, but the housing provided in the filter unit according to the embodiment of the present invention is not limited to this. The liquid inflow port 23 and the liquid outflow port 24 can be arranged at any position of the housing 20. At this time, the liquid inlet 23 is arranged so that the substance to be purified flows into the filter 10 from the outside of the filter 10, and the liquid outlet 24 is arranged so that the substance to be purified after purification can be taken out from the inside of the core of the filter 10. do it.

FIG. 4 is a schematic diagram of the filter unit 40 according to the first embodiment of the present invention. The filter unit 40 includes a primary housing 42 and a secondary housing in order from the direction in which the substance to be purified is supplied into a pipe line (consisting of 41(a) to 41(c)) into which the substance to be purified is supplied. 46 are arranged. The primary housing 42 (housing arranged on the primary side) is connected to the conduits 41 (a) and 41 (b) by the liquid inlet 43 and the liquid outlet 44, and the secondary housing 46 (arranged on the secondary side). The housing) is connected to the conduits 41(b) and 41(c) by a liquid inlet 47 and a liquid outlet 48.

In the filter unit 40 according to the above embodiment, the primary housing 42 (housing arranged on the primary side) accommodates the first filter. That is, the primary housing 42 corresponds to the first housing. The first filter is a filter including a filter medium containing a first polymer having a polydentate coordinating substituent (hereinafter, also referred to as “first filter medium”).
A secondary filter is housed in the secondary housing 46 (housing disposed on the secondary side) of the above housings. That is, the secondary housing 46 corresponds to the second housing. The second filter contains a second polymer having at least one bond selected from the group consisting of an amide bond, an imide bond, and an ester bond, and has a pore size of 50 nm or less (hereinafter referred to as “second filter material”). It is also referred to as ".").

The flow of the product to be purified is indicated by F _{1 to} F ₃ . The substance to be purified that has flowed in from the liquid inflow port 43 in the F ₁ direction is refined by the filter housed in the primary housing 42, and then taken out from the liquid outflow port 44. Next, the substance to be purified flows through the pipe line 41 in the direction indicated by F ₂ , flows from the liquid inlet 47 into the filter housed in the secondary housing 46, and is purified, and then from the liquid outlet 48. It is taken out of the filter unit 40 in the F ₃ direction.

〔filter〕
Below, the form of the filter medium with which each filter is provided is explained in full detail.

<First filter>
The first polymer contained in the first filtering material is not particularly limited as long as it has a polydentate coordinating substituent. Examples of the main chain skeleton of the first polymer include nylon such as 6-nylon and 6,6-nylon; polyolefins such as polyethylene and polypropylene; polystyrene; polyimide; polyamideimide; poly(meth)acrylate; Polytetrafluoroethylene, perfluoroalkoxyalkanes, perfluoroethylenepropene copolymers, ethylene-tetrafluoroethylene copolymers, ethylene-chlorotrifluoroethylene copolymers, polychlorotrifluoroethylene, polyvinylidene fluoride, and polyvinyl fluoride Fluorocarbon; polyvinyl alcohol; polyester; cellulose; cellulose acetate and the like. Among them, having a better solvent resistance, in that the resulting chemical solution has a better defect suppressing performance, the first polymer, as a first polymer, nylon having a polydentate substituent (among others, 6,6-nylon is preferable), polyolefin having a polydentate substituent (among others, polyethylene is preferable), poly(meth)acrylate having a polydentate substituent, and polydentate At least one selected from the group consisting of polyfluorocarbons having a pendant substituent (among these, polytetrafluoroethylene (PTFE) and perfluoroalkoxyalkanes (PFA) are preferable). These polymers may be used alone or in combination of two or more.

As the first polymer, for example, a polymer having a unit represented by the following formula (P) is preferable.

In formula (P), L _p represents a single bond or a divalent linking group, R _p represents a hydrogen atom, a halogen atom, or a monovalent organic group, and * represents a multidentate coordination property described later. Represents a bonding position with the substituent (also referred to as a specific substituent).
Examples of the monovalent organic group for R _p include an alkyl group having 1 to 5 carbon atoms and a halogenated alkyl group having 1 to 5 carbon atoms. The alkyl group having 1 to 5 carbon atoms of R _p is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specifically, methyl group, ethyl group, propyl group, isopropyl group, n -Butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group and the like can be mentioned. The halogenated alkyl group having 1 to 5 carbon atoms is a group in which part or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and a fluorine atom is particularly preferable.
As R, a hydrogen atom, a hydrogen atom or a methyl group is most preferable from the viewpoint of industrial availability.

The divalent linking group for L _p is not particularly limited, but includes —O—, —C(═O)—, —NR ₄ R ₅ —, a phenylene group, and —CR ₆ R ₇ —, and these. It represents at least one selected from the group consisting of combinations, and R ₄ , R ₅ , R ₆ , and R ₇ each independently represent a hydrogen atom or a monovalent organic group.

More specifically, _L as the divalent linking group for _{p -C (= O) -O -} , - C (= O) -, - O-C (= O) -O -, - C (= ^{O) -NH -, - Y 31} -O-Y 32 -, - Y 31 -O -, - Y 31 -C (= O) -O -, - C (= O) -O-Y 31 -, - ^{[Y 31 -C (= O)} -O] m '-Y 32 -, - Y 31 -O-C (= O) -Y 32 - group (wherein represented ^{by, Y 31} and ^{Y 32} each It is a linear or branched divalent aliphatic hydrocarbon group which may have a substituent independently, O is an oxygen atom, and m′ is an integer of 0 to 3.) Alternatively, a combination of these may be used.
When L _p is a divalent aromatic cyclic group, specific examples of the divalent aromatic cyclic group include benzene, biphenyl, fluorene, naphthalene, anthracene, and phenanthrene.

Specific examples of the unit represented by the formula (P) are shown below. In the formula, * represents a bonding position with a specific substituent described later.

The first filter medium contains a first polymer having a polydentate substituent (hereinafter, also referred to as “specific polymer”).
The specific polymer is obtained by introducing a polydentate substituent into the above polymer. In the specific polymer, the bonding form of the first polymer and the specific substituent is not particularly limited, and directly or in the main chain of the polymer, or a linking group (amide group, imide group, ether group, and ester At least one selected from the group consisting of groups is preferable), and the specific substituent may be bonded thereto. At this time, the bonding position may be at the end of the main chain of the polymer or at a position other than the end. Further, the specific polymer may be one in which a polymer chain having a specific substituent is bonded to the main chain of the polymer as a graft chain.

The structure of the specific substituent is not particularly limited, but the number of ring members of the chelate ring formed by combining with the metal atom is preferably 5 or more, more preferably 6 or more, and further preferably 7 or more.
The coordination number of the specific substituent is not particularly limited as long as it is 2 or more, but 3 or more is preferable, and 6 or more is more preferable.

As the specific substituent, for example, a substituent represented by the following formula (CLT) is preferable.

In formula (CLT), in the formula, L ₁ and L ₃ represent a single bond or a divalent linking group, L ₂ represents a divalent linking group, and X contains a hydrogen atom, an alkyl group, or a carboxy group. Or a group containing a phosphonium group, m and n each represent an integer of 0 or 1 or more, the sum of m and n is 1 or more, and a plurality of L ₂ , L ₃ and X are They may be the same or different, * represents the bonding position with the main chain of the first polymer. Further, Xs may be linked to each other to form a ring.

The divalent linking group of L ₁ , L ₂ and L ₃ includes a divalent aliphatic group (for example, an alkylene group, a substituted alkylene group, an alkenylene group, a substituted alkenylene group, an alkynylene group, and a substituted alkynylene group. Etc.), a divalent aromatic group (for example, an arylene group, and a substituted arylene group), a divalent heterocyclic group, an oxygen atom (-O-), a sulfur atom (-S-), an imino group (- NH-), a substituted imino group _{(-NR 31} -, wherein _{R 31} can be mentioned aliphatic group, an aromatic group or a heterocyclic group), a carbonyl group (-CO-), and the like combinations thereof ..
Among them, the divalent linking group is at least selected from the group consisting of a carbonyl group, an oxygen atom, an alkylene group, and a combination thereof in that a filter unit having a more excellent effect of the present invention can be obtained. One kind is preferable.

More specifically, the group represented by the formula (CLT) includes groups represented by the following formulas. Each symbol in the formula has the same meaning as each symbol in formula (CLT).

Further, in the group represented by the formula (CLT), examples of the case where X's are linked to each other to form a ring include the groups represented by the following formulas. Each symbol in the formula has the same meaning as each symbol in formula (CLT).

Further, the specific substituent may be a cyclic polyether group represented by the following formula (CP).

In formula (CP), p represents 0 or an integer of 1 or more, q represents an integer of 1 or more, and * represents a bonding position. Specific examples of the cyclic polyether group include, for example, 1-aza-12-crown-4, 1-aza-13-crown-4, 1-aza-14-crown-4, 1-aza-15-crown. -5, 1-aza-16-crown-5, 1-aza-17-crown-5, 1-aza-18-crown-6, 1-aza-20-crown-6, 1-aza-21-crown -7 and 1-aza-24-crown-8 include groups in which one hydrogen atom on the nitrogen atom has been removed.

The method of bonding (introducing) the specific substituent to the main chain of the polymer is not particularly limited, and a known method can be used. For example, the polymer is irradiated with ionizing radiation (for example, electron beams, gamma rays, neutron rays, and ultraviolet rays) to generate radicals, and the radicals have a specific substituent and a polymerizable group. A method of reacting a monomer (for example, a compound having a vinyl group and a specific substituent) to form a graft polymer; irradiating the polymer with plasma to generate a reactive functional group such as a hydroxy group on the polymer surface. A method of reacting a compound having a specific substituent with the above reactive functional group; a method of reacting a compound having a specific substituent with a reactive functional group of a polymer (polyacrylonitrile etc.) originally having a reactive functional group And the like.

The compound having the specific substituent is not particularly limited, but for example, ethylenediaminetetraacetic acid, ethylenediaminedioltohydroxyphenylacetic acid, diaminopropanetetraacetic acid, nitrilotriacetic acid, hydroxyethylethylenediaminehexaacetic acid, hydroxyethylenediaminetriacetic acid, hydroxyethylimino. Diacetic acid, dihydroxyethylglycine, ethylenediaminediacetic acid, ethylenediaminedipropionic acid, iminodiacetic acid, diethylenetriaminepentaacetic acid, hydroxyethyliminodiacetic acid, diaminopropanoltetraacetic acid, transcyclohexanediaminetetraacetic acid, glycoletherdiaminetetraacetic acid, triethylenetetramine Hexaacetic acid, ethylenediaminetetrakismethylenephosphonic acid, nitrilotrimethylenephosphonic acid, 1-hydroxyethylidene-1,1-diphosphonic acid, 1,1-diphosphonoethane-2-carboxylic acid, 2-phosphonobutane-1,2,4-tricarboxylic acid, 1-hydroxy-1-phosphonopropane-1,2,3-tricarboxylic acid, catechol-3,5-diphosphonic acid, uramil diacetic acid, pyrophosphoric acid, tetrapolyphosphoric acid, hexametaphosphoric acid, L-aspartic acid diacetic acid, hydroxy Ethylglycine, malonic acid, oxalic acid, phthalic acid, glycolic acid, salicylic acid, 8-quinolinol, acetylacetone, trifluoroacetone, dimethylglyoxime, dithizone, salicylaldehyde, ethylenediamine, 2,2'-bipyridine, and 1,10 -Phenanthroline and the like.

Among them, the specific substituent is at least one selected from the group consisting of compounds represented by the following formulas (1) to (3), in that a filter unit having a more excellent effect of the present invention can be obtained. The group derived from the compound of is preferable.
In addition, the group derived from the above compound means a monovalent group formed by removing one hydrogen atom from a predetermined compound.

In formula (1), X ₁ represents a hydrogen atom, a carboxy group or a phosphonium group, L ₁ represents a single bond or a divalent linking group, n represents an integer of 1 or more, and 2 or more L's are present. ₁ and X ₁ may be the same or different, but not all X ₁ are hydrogen atoms at the same time.
In formula (2), X ₂ represents a hydrogen atom, a carboxy group or a phosphonium group, and A represents a divalent linking group having a hydroxy group. n represents 2.
In formula (3), n1 to n5 each independently represent an integer of 1 to 5, and R _{1 to} R ₃ each independently represent an oxygen atom or a group represented by —NX— (where X is a hydrogen atom). , Or a monovalent organic group) and a sulfur atom.

(Specific polymer)
The first polymer (specific polymer) having a polydentate coordinating group is not particularly limited, but in view of obtaining a filter unit having a more excellent effect of the present invention, the following formula (P- It is preferable to have a unit represented by 1).

In Formula (P-1), R _p represents a hydrogen atom, a halogen atom, or a monovalent organic group, W represents a polydentate substituent, and L _p represents —O— or —C. _{(= O) -, - NR} 4 R 5 -, a phenylene group, and,, _-CR 6 _{R 7} -, and represents at least one member selected from the group consisting _of, R _{4, R} 5, R ₆ and R ₇ each independently represent a hydrogen atom or a monovalent organic group.

Specific examples of units of the specific polymer are shown below.

Further, the specific polymer may have the following units.

In terms of obtaining a more excellent filter unit having the effect of the present invention, the chelate stability constant of the specific substituent preferably satisfies at least one requirement selected from the following (A) to (E): , (A) to (E) are more preferably satisfied.
(A) more than 4.5 for Al ³⁺ ions (B) more than 8.0 for Fe ³⁺ ions (C) more than 4.5 for Ti ³⁺ ions (D) for Na ⁺ ions The above metal ions exceeding 3.0 with respect to (E)K ⁺ ions exceeding 3.0 are particularly difficult to be removed in the process of refining the chemical solution, and thus easily cause defects. Therefore, when the chelate stability constant of the specific substituent satisfies the above requirements, the metal ions are less likely to flow out to the purified product, and as a result, a chemical liquid having more excellent defect suppressing performance can be obtained.
In the present specification, the chelate stability constant refers to L. G. Sillen, A.; E. Martell, "Stability Constants of Metal-ion Complexes," The Chemical Society, London (1964), S.M. Chaberek, A.; E. The constants generally known from “Organic Squeezing Agents” Wiley (1959) by Martell are intended.
The upper limit of each chelate stability constant is not particularly limited, but is generally preferably 20 or less for Al ³⁺ ions, more preferably less than 20, and preferably less than 25 for Fe ³⁺ ions, more preferably 20 or less. , Ti ³⁺ ions are preferably 20 or less, more preferably less than 20, more preferably Na ⁺ ions are preferably 20 or less, more preferably less than 15, and K ⁺ ions are preferably 20 or less, less than 15 Is preferred.

Among them, in view of obtaining a filter unit having a particularly excellent effect of the present invention, the chelate stability constant of the specific substituent must satisfy at least one requirement selected from the following (F) to (J). Is particularly preferable.
(F) is 6.0 to 20 for Al ³⁺ ions, and is more than 8.0 for (G)Fe ³⁺ ions, and is 6.0 or less for 20 or less (H)Ti ³⁺ ions. It is 6.0 to 20 for certain (I)Na ⁺ ions and 6.0 to 20 for (J)K ⁺ ions.

Among them, the chelate stability constant of the specific substituent satisfies at least one requirement selected from the following (K) to (O), in that a filter unit having the most excellent effect of the present invention can be obtained. Is most preferable, and it is more preferable to satisfy all the requirements (K) to (O).
More than 6.0 for (K)Al ³⁺ ions and less than 20 more than 10 for (L)Fe ³⁺ ions and more than 6.0 for less than 20 (M)Ti ³⁺ ions. , Less than 20, more than 5.0 for (N)Na ⁺ ions, less than 15 more than 5.0, less than 15 for (O)K ⁺ ions

The first filtering material may be either a depth type or a screen type. For example, the depth-type first filter material can be obtained by compression molding of fibers formed by using a predetermined material, and the screen-type first filter material is formed by using a predetermined material. It can be obtained by stretching the film.

The pore size of the first filter medium is not particularly limited, but is preferably 200 μm or less, more preferably 100 nm or less, and further preferably 50 nm or less. Further, it is preferably 3 nm or more, more preferably 10 nm or more, still more preferably 15 nm or more. In the present specification, the pore size means the maximum pore size determined by the bubble point method using isopropanol.

(Requirement 1)
The first filter preferably satisfies the requirement 1 in the following elution test (hereinafter also referred to as “specific test”) in that a filter unit having a more excellent effect of the present invention can be obtained.

Specific test: The mass ratio of the mass (g) of the first filter to the mass (g) of the test solvent containing 99.99 mass% or more of isopropanol is 1.0 when the liquid temperature of the test solvent is 25°C. The first filter is immersed in a test solvent having a liquid temperature of 25° C. for 48 hours under the following conditions.
Requirement 1: When one organic impurity is contained in the test solvent after immersion, the amount of increase of one organic impurity before and after immersion is 1000 mass ppm or less, and the isopropanol after immersion contains two or more organic impurities. When impurities are contained, the total amount of increase of two or more kinds of organic impurities before and after immersion is 1000 mass ppm or less.
The lower limit of the amount of increase in the amount of organic impurities before and after immersion is not particularly limited, and is generally 1.0 mass ppq or more, although it depends on the lower limit of quantification. When the test solvent contains two or more kinds of organic impurities, the total amount thereof is preferably the above lower limit value or more.

In the present specification, the organic impurities mean organic compounds other than IPA in the test solvent. A gas chromatograph mass spectrometer (product name “GCMS-QP2020”, manufactured by Shimadzu Corporation) is used for measuring the content of organic impurities. The measurement conditions are as described in the examples. Although not particularly limited, when the organic impurities have a high molecular weight, Py-QTOF/MS (pyrolyzer quadrupole time-of-flight mass spectrometry), Py-IT/MS (pyrolyzer ion trap mass spectrometry), Py-Sector/MS (pyrolyzer magnetic field type mass spectrometry), Py-FTICR/MS (pyrolyzer Fourier transform ion cyclotron type mass spectrometry), Py-Q/MS (pyrolyzer quadrupole type mass spectrometry), and Py -IT-TOF/MS (pyrolyzer ion trap time-of-flight mass spectrometry) may be used to identify the structure and quantify the concentration from the decomposed product. For example, for Py-QTOF/MS, a device manufactured by Shimadzu Corporation can be used.

The test solvent contains isopropanol, and the content thereof is 99.99% by mass or more. The solvent is commercially available as high-purity isopropanol for semiconductor production.
The specific test is performed according to the following procedure. Place the test solvent in a container. Next, the first filter is put in a container, the entire first filter is immersed in the test solvent, the liquid temperature of the first filter and the test solvent becomes 25° C., and the test solvent is prevented from concentrating. Keep on time. At this time, the mass ratio of the mass (g) of the test solvent and the mass (g) of the first filter is 1.0 (100%) when the liquid temperature of the test solvent is 25°C. For example, when the mass of the first filter is 250 g, it is immersed in 250 g (25° C.) of the test solvent.
The container used in the specific test uses the above-mentioned test solvent as a cleaning liquid in advance and uses the container that has been cleaned with the above-mentioned cleaning liquid. In addition, it is preferable to use a test container that does not elute organic impurities from itself, but if organic impurities may elute from the test container, perform a blank test by the following method and perform a test. Subtract the amount of organic impurities eluted from the container from the results.
(Blank test)
The test solvent is stored in the test container in the same mass as that used in the specific test, and the test solvent has a liquid temperature of 25° C. and is maintained for 48 hours so that the test solvent is not concentrated. At this time, the increased amount of organic impurities in the test solvent before and after 48 hours is taken as the elution amount from the container.

Next, the test solvent after immersion (25° C.) is sampled, and the content of organic impurities (mass reference, for example, mass ppt) Or ₂ is measured. At this time, when two or more kinds of organic impurities are contained in the test solvent after immersion, Or ₂ is the total amount thereof.
Here, the content of the organic impurities contained in the pre-immersion test solvent measured in advance Or ₁ (mass standard, the same unit as Or ₂ is contained, and the test solvent before the test contains two or more kinds of organic impurities. In this case, Or ₁ is the total amount thereof.), and the increase amount before and after the immersion of the organic impurities is calculated as Or ₂ —Or ₁ . In addition, when the blank test was performed, the increase amount before and after the immersion of the organic impurities was Or ₂ -Or _B using the organic impurities Or _B (mass standard, the same unit as Or ₂ ) in the blank test. Is expressed as

When the increase amount of the organic impurities is 1000 mass ppm or less, a filter unit having more excellent effects of the present invention can be obtained. Further, the amount of increase in the organic impurities is more preferably 1.0 mass ppt to 1.0 mass ppm from the viewpoint that a filter unit having a more excellent effect of the present invention can be obtained.

(Requirement 2)
The first filter preferably satisfies the requirement 2 in the specific test in that a filter unit having a more excellent effect of the present invention can be obtained.
Requirement 2: When one kind of metal ion is contained in the test solvent after immersion, the amount of increase of one kind of metal ion before and after immersion is 100 mass ppm or less, and two or more kinds in the test solvent after immersion. When metal ions are contained, the total amount of increase before and after the immersion of two or more metal ions is 100 mass ppm or less.
The lower limit of the amount of increase before and after immersion is not particularly limited, and is generally 1.0 mass ppq or more, although it depends on the lower limit of quantification. When the test solvent contains two or more kinds of metal ions, the total amount thereof is preferably the above lower limit value or more.

The content of the metal ion in the present specification means the content of the metal ion measured by the SP-ICP-MS method (Single Nano Particle Inductively Coupled Plasma Mass Spectrometry).
Here, the device used in the SP-ICP-MS method is the same as the device used in the ordinary ICP-MS method (inductively coupled plasma mass spectrometry) (hereinafter, also simply referred to as “ICP-MS”). And only the data analysis is different. Data analysis as SP-ICP-MS can be performed by commercially available software.
In ICP-MS, the content of the metal component to be measured is measured regardless of its existing form. Therefore, the total mass of the metal particles to be measured and the metal ions is quantified as the content of the metal component.

On the other hand, in SP-ICP-MS, the content of metal particles is measured. Therefore, the content of the metal ions in the sample can be calculated by subtracting the content of the metal particles from the content of the metal component in the sample.
As the apparatus for the SP-ICP-MS method, for example, Agilent 8800 triple quadrupole ICP-MS (inductively coupled plasma mass spectrometry, for semiconductor analysis, option #200) manufactured by Agilent Technologies, Inc. was used and described in the examples. It can be measured by a method. In addition to the above, in addition to NexION350S manufactured by PerkinElmer, Agilent 8900 manufactured by Agilent Technology is also included.

Specifically, the increase amount before and after the immersion of the metal ion is calculated by the following method.
After the immersion, the test solvent (25° C.) is sampled, and the metal ion content MI ₂ is measured. At this time, when two or more kinds of metal ions are contained in the test solvent after immersion, MI ₂ is the total amount thereof.
Here, the content of metal ions MI ₁ contained in the test solvent before immersion measured in advance (in the case where the test solvent before the test contains two or more kinds of metal ions, MI ₁ is the sum of them). The increase amount before and after the immersion of the metal ion is calculated as MI ₂ −MI ₁ .

When the increase amount of the metal ions before and after the immersion is 100 mass ppm or less, a filter unit having a more excellent effect of the present invention can be obtained. Further, the amount of increase of the metal ions is more preferably 1.0 mass ppt to 1.0 mass ppm from the viewpoint that a filter unit having a more excellent effect of the present invention can be obtained.

(Requirement 3)
The first filter preferably satisfies the requirement 3 in the specific test in that a filter unit having a more excellent effect of the present invention can be obtained.
Requirement 3: When one kind of metal particles is contained in the test solvent after the immersion, the increase amount of one kind of the metal particles before and after the immersion is 100 mass ppm or less, and two or more kinds in the test solvent after the immersion. When the metal particles are contained, the total amount of increase before and after the immersion of two or more kinds of metal particles is 100 mass ppm or less.
The lower limit of the amount of increase before and after immersion is not particularly limited, and is generally 1.0 mass ppq or more, although it depends on the lower limit of quantification. When two or more kinds of metal particles are contained in the test solvent, the total amount thereof is preferably the above lower limit value or more.

When the increase amount of the metal particles before and after the immersion is 100 ppm by mass or less, a filter unit having a more excellent effect of the present invention can be obtained. Further, the increase amount of the metal particles is more preferably 1.0 mass ppt to 1.0 mass ppm from the viewpoint that a filter unit having a more excellent effect of the present invention can be obtained.

<Second filter>
The second filter contains a second polymer having at least one bond selected from the group consisting of an amide bond, an imide bond, and an ester bond, and has a pore diameter of 50 nm or less (second filter material). It is a filter provided with.

Examples of the second polymer include polyamide, polyimide, polyester, polyamideimide, polyesterimide, and polyesteramide. Those obtained by copolymerizing or graft-polymerizing these, or a polymer blend obtained by mixing these. May be Among them, polyamide is preferable in that a filter unit having a more excellent effect of the present invention can be obtained.
Nylon is more preferred as the polyamide. Examples of nylon include nylon 6 and nylon 66. The second filter material may be a depth type, a screen type or the like.

The pore size of the second filter medium is 50 nm or less. Among them, the pore size of the second filtering material is preferably 1.0 to 30 nm, more preferably 1.0 to 15 nm, and more preferably 2.0 to 15 nm in that a filter unit having a more excellent effect of the present invention can be obtained. Is more preferable. Further, in the combination with the first filtering material, the pore diameter of the second filtering material is preferably smaller than the pore diameter of the first filtering material. In that case, the ratio of the pore size (nm) of the second filter medium to the pore size (nm) of the first filter medium (pore size of the second filter medium/pore size of the first filter medium) is 0.10 to 0.99. More preferably, it is more preferably 0.10 to 0.90, and particularly preferably 0.20 to 0.90.

Regarding the first filter material and the second filter material, the relationship between the chemical liquid and the material of the filter medium is the filter medium from the viewpoint that the metal components (metal ions and metal particles) are less likely to increase when the chemical liquid is stored. The relational expression (Ra/R0) between Ra and R0, where the interaction radius (R0) in the Hansen solubility parameter space that can be derived from the material of (1) and the radius of the sphere of the Hansen space (Ra) that can be derived from the organic solvent contained in the chemical liquid are used. It is preferable that the chemical liquid is a combination satisfying ≦1 and purified with a material satisfying these relational expressions. (Ra/R0)≦0.98 is preferable, and (Ra/R0)≦0.95 is more preferable. The lower limit is preferably 0.5 or higher, more preferably 0.6 or higher, and even more preferably 0.7. The mechanism is not clear, but if it is within this range, the increase of metal components in the chemical solution during long-term storage is suppressed.
The combination of these materials and the organic solvent is not particularly limited, and examples thereof include those of US2016/0089622.

(Requirement 4)
The second filter preferably satisfies the requirement 4 in the following test (hereinafter also referred to as “specific test 2”) in that a filter unit having a more excellent effect of the present invention can be obtained.

Specific test 2: The mass (g) ratio of the mass of the second filter to the mass (g) of the test solvent containing 99.99 mass% or more of isopropanol is 1. When the liquid temperature of the test solvent is 25°C. The second filter is immersed in the test solvent having a liquid temperature of 25° C. for 48 hours under the condition of 0.
Requirement 4: When one kind of organic impurities is contained in the test solvent after the immersion, the increase amount of one kind of the organic impurities before and after the immersion is 1000 mass ppm or less, and the test solvent after the immersion contains two or more kinds. When an organic impurity is contained, the total amount of increase of two or more kinds of organic impurities before and after immersion is 1000 mass ppm or less.
The lower limit of the amount of increase before and after immersion is not particularly limited, and is generally 1.0 mass ppq or more, although it depends on the lower limit of quantification. When the test solvent contains two or more kinds of organic impurities, the total amount thereof is preferably the above lower limit value or more.

The specific test 2 is the same as the specific test described above except that the second filter is used instead of the first filter, and therefore the description thereof is omitted.
When the increase amount of the organic impurities is 1000 mass ppm or less, a filter unit having more excellent effects of the present invention can be obtained. Further, the amount of increase in the organic impurities is more preferably 1.0 mass ppt to 1.0 mass ppm from the viewpoint that a filter unit having a more excellent effect of the present invention can be obtained.

(Requirement 5)
The second filter preferably satisfies the requirement 5 in the specific test 2 in that a filter unit having a more excellent effect of the present invention can be obtained.
Requirement 5: When one kind of metal ion is contained in the test solvent after immersion, the amount of increase of one kind of metal ion before and after immersion is 100 mass ppm or less, and two or more kinds in the test solvent after immersion. When metal ions are contained, the total amount of increase before and after the immersion of two or more metal ions is 100 mass ppm or less.
The lower limit of the amount of increase before and after immersion is not particularly limited, and is generally 1.0 mass ppq or more, although it depends on the lower limit of quantification. When the test solvent contains two or more kinds of metal ions, the total amount thereof is preferably the above lower limit value or more.

When the increase amount of the metal ions before and after the immersion is 100 mass ppm or less, a filter unit having a more excellent effect of the present invention can be obtained. Further, the amount of increase of metal ions is more preferably 1.0 mass ppt to 1.0 mass ppm from the viewpoint that a filter unit having a more excellent effect of the present invention can be obtained.

(Requirement 6)
The second filter preferably satisfies the requirement 6 in the specific test 2 in that a filter unit having a more excellent effect of the present invention can be obtained.
When the test solvent after immersion contains one kind of metal particles, the increase amount before and after immersion of one kind of metal particles is 100 mass ppm or less, and the test solvent after immersion contains two or more kinds of metal particles. When included, the total amount of increase before and after the immersion of two or more kinds of metal particles is 100 mass ppm or less.
The lower limit of the amount of increase before and after immersion is not particularly limited, and is generally 1.0 mass ppq or more, although it depends on the lower limit of quantification. When two or more kinds of metal particles are contained in the test solvent, the total amount thereof is preferably the above lower limit value or more.

When the increase amount of the metal particles before and after the immersion is 100 ppm by mass or less, a filter unit having a more excellent effect of the present invention can be obtained. In addition, the amount of increase of the metal particles is more preferably 1.0 mass ppt to 1.0 mass ppm from the viewpoint that a filter unit having a more excellent effect of the present invention can be obtained.

In the filter unit 40 according to the first embodiment of the present invention, the primary housing 42 houses the first filter having the first filtering material, and the secondary housing 46 houses the second filter having the second filtering material.
Since the first filtering material contains the first polymer having a specific substituent, the ionic organic impurities and metal ions contained in the substance to be purified can be efficiently removed. Furthermore, since the second filter, which is made of nylon and has a second filter material having a pore size of 50 nm or less, is housed in the secondary housing, by repeatedly using the first filter, ionic organic impurities, and Even if metal ions have been eluted from the first filter, they can be removed by the second filter. As a result, according to the above filter unit, a chemical liquid having more excellent defect suppressing performance can be obtained.

It should be noted that the filter unit according to the embodiment of the present invention is not limited to the above-described form, and the second filter including the second filtering material is housed in the primary housing 42 (that is, the primary housing 42 is the second housing). ), the 1st filter provided with the 1st filtration material may be stored in the secondary housing 46 (namely, the secondary housing 46 is a 1st housing).

〔housing〕
The filter unit according to the embodiment of the present invention has a housing. The shape of the housing is not particularly limited, and a housing having a known shape can be used.
The material of the housing is not particularly limited, but in view of less elution of impurities (organic impurities, etc.) from the housing, it is possible to use the polymer already described as the polymer that can be used for the first filter medium. However, at least one selected from the group consisting of polyethylene and polyfluorocarbon is preferable. Further, it may be formed of a corrosion resistant material described later.

[Second Embodiment of Filter Unit]
The filter unit according to the second embodiment of the present invention is different from both the first filter and the second filter in that at least one selected from the group consisting of a filter material and a pore size of the filter is different. The filter unit further includes a housing in which three filters are housed.
The filter unit according to the above embodiment will be described with reference to FIG. In addition, in the following description, the modes and conditions not described are the same as those of the filter unit according to the first embodiment already described.

FIG. 5 is a schematic diagram of the filter unit 50 according to the above embodiment. The filter unit 50 includes a primary housing 42, a secondary housing 46, and a primary housing 42 in order from the direction in which the substance to be purified is supplied into a pipe line (consisting of 41(a) to 41(d)) into which the substance to be purified is supplied. Also, the tertiary housing 51 is arranged.
The tertiary housing 51 is connected to the conduits 41(c) and 41(d), the liquid inlet 52, and the liquid outlet 53.

In the filter unit 50 according to the above-described embodiment, the primary housing 42 houses the third filter (hereinafter, the housing housing the third filter is also referred to as “third housing”), and the secondary housing 46. Accommodates the first filter (that is, "corresponds to the first housing"), and the third housing 51 accommodates the second filter (that is, corresponds to the second housing).

The flow of the product to be purified is indicated by F _{1 to} F ₄ . The substance to be purified that has flowed into the primary housing 42 from the conduit 41(a) in the F ₁ direction via the liquid inlet 43 is purified by the third filter housed in the primary housing 42, and then the liquid outlet. It is taken out from 44. Next, the substance to be purified flows through the pipe line 41(b) in the F ₂ direction, passes through the liquid inflow port 47, and flows into the secondary housing 46. The substance to be purified is purified by the first filter housed in the secondary housing 46, and then taken out from the liquid outlet 48. Next, the substance to be purified flows through the conduit 41(c) in the F ₃ direction, passes through the liquid inflow port 52, and flows into the tertiary housing 51. The substance to be purified is purified by the second filter housed in the tertiary housing 51, then taken out from the liquid outlet 53, and flows in the pipe line 41(d) in the F ₄ direction.

<Third filter>
The filter medium (third filter medium) included in the third filter is different from both the first filter medium and the second filter medium in at least one selected from the group consisting of materials and pore diameters.
Among them, the pore size of the third filter medium is preferably larger than the pore size of the first filter medium in that the life of the first filter medium can be extended.
The material of the third filtering material is not particularly limited, and for example, the materials already described as the first polymer contained in the first filtering material can be used.

In the filter unit 50 according to the above-described embodiment, the primary housing 42 (third housing) in which the third filter including the third filter medium is stored and the first filter including the first filter medium are sequentially stored from the primary side. A secondary housing 46 (first housing) and a tertiary housing 51 (second housing) accommodating a second filter including a second filtering material are arranged.
By disposing the third housing on the primary side of the first housing, the life of the first filter can be extended. This tendency is more remarkable when the pore size of the third filter medium is larger than that of the first filter medium.

The arrangement of the filters in the filter unit according to the embodiment of the present invention is not limited to the above. That is, the first housing 42, the second housing 46, and the third housing 51 may be provided with the first filter, the second filter, and the third filter, respectively. For example, each housing may house the second filter, the third filter, and the first filter in this order from the primary side.

[Refining equipment]
The refining device according to the embodiment of the present invention includes the filter unit already described. The refining device will be described with reference to FIG.
FIG. 6 is a schematic diagram of a refining device 60 including the filter unit 40. The refining device 60 includes a filter unit 40, a manufacturing tank 61, and a filling device 66, which are connected by a pipe line 62. Valves 63 and 65 and a pump 64 are arranged in the conduit 62.

The product to be purified stored in the manufacturing tank 61 flows in the F ₁ direction in the pipe line 62 and flows into the filter unit 40 by operating the pump 64 when the valve 63 is opened. The substance to be purified that has been purified by the filter unit 40 flows through the pipe 62 in the F ₂ direction, passes through the valve 65, and is filled in the container by the filling device 66.
Note that the purified object to be refined may be returned to the manufacturing tank 61 again and flow into the filter unit 40 again (may be circulated for purification, hereinafter also referred to as “circulation purification”). In that case, it can be carried out by flowing the purified object to be purified flowing in the F ₂ direction in the F ₄ direction by operating the valve 65 and returning it to the manufacturing tank 61.

The refining device 60 includes the filter unit 40, but the refining device according to the present embodiment is not limited to this, and may include the filter unit 50 already described. Since the filter unit 50 includes the third filter in the primary housing, the life of the first filter housed in the housing arranged on the secondary side can be extended even in the case of circulation refining.

[Corrosion resistant material]
The material of the housing, the manufacturing tank, the pipeline, and the liquid contact portion of each of the filling devices is not particularly limited, but a fluororesin and electrolytically polished in that a chemical liquid having more excellent defect suppressing performance can be obtained. Formed of at least one material selected from the group consisting of metallic materials (corrosion-resistant material), the metallic material contains at least one material selected from the group consisting of chromium and nickel. The total content is preferably more than 25 mass% with respect to the total mass of the metal material. In addition, when the liquid contact part is formed of the above material, each of the members is formed of the above material, or the liquid contact part of each member is coated with the above material to form a coating layer. Are listed.

<Electro-polished metal material (electro-polished metal material)>
The metal material used for producing the electropolished metal material contains at least one selected from the group consisting of chromium and nickel, and the total content of chromium and nickel is based on the total mass of the metal material. There is no particular limitation as long as it is a metal material having a content of more than 25% by mass, and examples thereof include stainless steel and nickel-chromium alloy.
The total content of chromium and nickel in the metal material is preferably 25 mass% or more, and more preferably 30 mass% or more with respect to the total mass of the metal material.
The upper limit of the total content of chromium and nickel in the metal material is not particularly limited, but generally 90% by mass or less is preferable.

The stainless steel is not particularly limited, and known stainless steel can be used. Among them, an alloy containing nickel in an amount of 8% by mass or more is preferable, and an austenitic stainless steel containing nickel in an amount of 8% by mass or more is more preferable. Examples of the austenitic stainless steel include SUS (Steel Use Stainless) 304 (Ni content 8% by mass, Cr content 18% by mass), SUS304L (Ni content 9% by mass, Cr content 18% by mass), SUS316 ( Ni content 10 mass %, Cr content 16 mass %), SUS316L (Ni content 12 mass %, Cr content 16 mass %) and the like.
The Ni content and the Cr content in the parentheses are content ratios with respect to the total mass of the metal material.

The nickel-chromium alloy is not particularly limited, and a known nickel-chromium alloy can be used. Above all, a nickel-chromium alloy having a nickel content of 40 to 75% by mass and a chromium content of 1 to 30% by mass is preferable with respect to the total mass of the metal material.
Examples of the nickel-chromium alloy include Hastelloy (trade name, hereinafter the same), Monel (trade name, hereinafter the same), Inconel (trade name, the same below), and the like. More specifically, Hastelloy C-276 (Ni content 63 mass%, Cr content 16 mass%), Hastelloy-C (Ni content 60 mass%, Cr content 17 mass%), Hastelloy C-22 ( Ni content is 61 mass %, Cr content is 22 mass %) and the like.
Further, the nickel-chromium alloy may further contain boron, silicon, tungsten, molybdenum, copper, cobalt, and the like, in addition to the above alloys, if necessary.

The method of electrolytically polishing the metal material is not particularly limited, and a known method can be used. For example, the method described in paragraphs [0011]-[0014] of JP-A-2015-227501, paragraphs [0036]-[0042] of JP-A-2008-264929, and the like can be used.

It is presumed that the content of chromium in the passivation layer on the surface of the metal material is higher than the content of chromium in the matrix by being electrolytically polished. Therefore, it is presumed that the chemical liquid with a reduced impurity content can be obtained because the metal component is less likely to flow into the chemical liquid from the liquid contact portion formed of the corrosion resistant material.
The metal material may be buffed. The buffing method is not particularly limited, and a known method can be used. The size of the abrasive grains used for the buffing finish is not particularly limited, but #400 or less is preferable from the viewpoint that the unevenness of the surface of the metal material is likely to become smaller. The buffing is preferably performed before the electrolytic polishing.

<Fluorine resin>
The fluororesin is not particularly limited as long as it is a resin (polymer) containing a fluorine atom, and known fluororesins can be used. Examples of the fluororesin include polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinylidene fluoride, tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, tetrafluoroethylene-ethylene. Examples thereof include copolymers, chlorotrifluoroethylene-ethylene copolymers, and perfluoro(butenyl vinyl ether) cyclized polymers (CYTOP (registered trademark)).

The method for producing each of the above members is not particularly limited, and can be produced by a known method. For example, a method of sticking a fluororesin lining to a liquid contact portion of each member formed of metal or resin, and a composition containing a fluororesin in the liquid contact portion of each member formed of metal or resin According to the method of applying the above to form a coating film, it is possible to manufacture each member whose inner wall is coated with the above material (corrosion resistant material).
Further, for example, according to a method of electrolytically polishing the liquid contact portion of each member formed of a metal material whose total content of chromium and nickel is more than 25 mass% with respect to the total mass of the metal material, the inner wall is Each member made of a material (corrosion resistant material) can be manufactured.

[Purification method of chemicals]
Hereinafter, a method for purifying a chemical liquid containing an organic solvent using the chemical liquid purification device 60 according to the embodiment of the present invention will be described. The method of purifying the chemical liquid using the purifying device is not particularly limited, but it is preferable to have a step (purification step) of filtering the substance to be purified using a filter provided in the filter unit.

<Refining process>
The substance to be purified containing the organic solvent is first stored in the manufacturing tank 61.
The shape and capacity of the manufacturing tank are not particularly limited, and can be appropriately changed depending on the amount and/or type of the chemical solution to be manufactured.
The manufacturing tank may further be provided with a stirring blade or the like for stirring the contained substance to be purified, but in this case, the liquid contact portion of the stirring blade or the like should also be formed using a corrosion resistant material. Is preferred.

When the valve 63 is opened, the substance to be purified contained in the manufacturing tank 61 is moved in the pipe line 62 along the F ₁ direction by the pump 64 and introduced into the filter unit 40. The substance to be refined introduced into the filter unit 40 is refined by passing through a filter material provided in the filter. The form of the filter included in the filter unit has already been described.

Since the pressure (filtering pressure) when the substance to be purified is passed through the filter affects the filtering accuracy, it is preferable that the pulsation of the filtering pressure is as small as possible.
The flow rate (filtration rate) when passing the substance to be purified through the filter is not particularly limited, but 1.0 L/min/m ² or more is preferable, and a value of 0. 75 L/min/m ² or more is more preferable, and 0.6 L/min/m ² or more is further preferable.
The filter is set with a withstand pressure differential that guarantees filter performance (the filter is not broken). If this value is large, the filtration speed can be increased by increasing the filtration pressure. That is, the upper limit of the filtration rate usually depends on the differential pressure resistance of the filter, but is usually 10.0 L/min/m ² or less. On the other hand, by reducing the filtration pressure, the amount of particulate foreign substances or impurities dissolved in the chemical liquid can be efficiently reduced, and the pressure can be adjusted according to the purpose.

The filtration pressure is preferably 0.001 to 1.0 MPa, more preferably 0.003 to 0.5 MPa, and further preferably 0.005 to 0.3 MPa from the viewpoint that a chemical solution having a more excellent effect of the present invention can be obtained. preferable. In particular, when a filter provided with a filter medium having a small pore size is used, the amount of particulate foreign matter or impurities dissolved in the chemical liquid can be efficiently reduced by lowering the filtration pressure. When using a filter including a filter material having a pore size of less than 20 nm, the filtration pressure is particularly preferably 0.005 to 0.3 MPa.

Further, if the pore size of the filter material included in the filtration filter becomes smaller, the filtration rate will decrease. However, when a plurality of filtration filters of the same type are connected in parallel, the filtration area is expanded and the filtration pressure is reduced, which makes it possible to compensate for the reduction in filtration speed.

The purification step may be performed once or may be repeated multiple times. When the refining process is repeated a plurality of times, the valve 65 in FIG. 6 is operated to flow the object to be refined from the filter unit in the F ₂ direction and then to the F ₄ direction, and the object to be refined after purification is again supplied to the manufacturing tank 61. The method of returning to. The refined object returned to the manufacturing tank 61 is refined again by the above procedure.

(Cleaning process: process of cleaning the filter)
The chemical liquid purification method according to the embodiment of the present invention preferably further includes a step of cleaning the filter. The method for cleaning the filter is not particularly limited, and examples include a method of immersing the filter in the cleaning solution, a method of passing the cleaning solution through the filter, and a method of combining them.

The cleaning liquid is not particularly limited, and a known cleaning liquid can be used. The washing liquid is not particularly limited, and examples thereof include water and organic solvents. As the organic solvent, an organic solvent that can be contained in the liquid medicine, for example, alkylene glycol monoalkyl ether carboxylate, alkylene glycol monoalkyl ether, alkyl lactate ester, alkyl alkoxypropionate, cyclic lactone (preferably having 4 to 10 carbon atoms), It may be a monoketone compound which may have a ring (preferably having 4 to 10 carbon atoms), alkylene carbonate, alkyl alkoxyacetate, alkyl pyruvate and the like.

More specifically, as the cleaning liquid, for example, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, dimethyl sulfoxide, n-methyl-2-pyrrolidone, diethylene glycol, ethylene glycol, dipropylene glycol, propylene glycol, ethylene carbonate, carbonic acid. Examples thereof include propylene, sulfolane, cyclohexane, cyclohexanone, cycloheptanone, cyclopentanone, 2-heptanone, γ-butyrolactone, and mixtures thereof.

<Other processes>
The method for purifying the chemical liquid may have other steps. Other processes include, for example, an ion exchange process and a static elimination process.

(Ion exchange process)
The ion exchange step means a step of passing a chemical solution containing an organic solvent through the ion exchange unit. The method for passing the chemical solution containing the organic solvent through the ion exchange unit is not particularly limited, and the ion exchange unit is arranged in the middle of the conduit of the purification apparatus for the chemical solution already described, and the ion exchange unit is pressurized. Alternatively, a method of passing an organic solvent without pressure may be used.

The ion exchange unit is not particularly limited, and a known ion exchange unit can be used. Examples of the ion exchange unit include a column-shaped container containing an ion exchange resin, an ion adsorption membrane, and the like.

As one mode of the ion exchange step, a cation exchange resin or anion exchange resin provided as a single bed as the ion exchange resin, a cation exchange resin and an anion exchange resin provided as a multiple bed, and a cation exchange resin, Examples include a step of using a mixed bed with an anion exchange resin.
As the ion exchange resin, it is preferable to use a dry resin containing as little water as possible in order to reduce the elution of water from the ion exchange resin. As such a dry resin, a commercially available product can be used, and 15JS-HG/DRY (trade name, dry cation exchange resin, water content 2% or less) manufactured by Organo, and MSPS2-1/DRY (trade name, Mixed bed resin, water content 10% or less) and the like.

Another form of the ion exchange process is a process using an ion adsorption membrane.
By using an ion adsorption film, processing at a high flow rate is possible. The ion adsorption film is not particularly limited, and examples thereof include Neoceptor (trade name, manufactured by Astom Co.).

(Static elimination process)
The charge eliminating step is intended to reduce the charge potential by eliminating the charge of the chemical solution containing the organic solvent.
The static elimination method is not particularly limited, and a known static elimination method can be used. Examples of the static elimination method include a method in which a chemical solution containing an organic solvent is brought into contact with a conductive material.
The contact time for bringing the chemical liquid containing the organic solvent into contact with the conductive material is preferably 0.001 to 60 seconds, more preferably 0.001 to 1 second, and further preferably 0.01 to 0.1 seconds. Examples of conductive materials include stainless steel, gold, platinum, diamond, and glassy carbon.
Examples of a method of contacting a conductive material with a chemical containing an organic solvent include, for example, a method in which a grounded mesh made of a conductive material is placed inside a pipe, and a chemical containing an organic solvent is passed therethrough. To be

[Chemical solution]
According to the above-mentioned purification device, it is possible to obtain a chemical liquid having excellent defect suppressing performance.
The chemical solution is preferably a chemical solution in which metal impurities (metal particles, metal ions) and organic impurities are reduced. Without limitation, abrasives used for semiconductor manufacturing, liquids containing resist compositions, pre-wetting liquids, developing liquids, rinsing liquids, and high-purity peeling liquids, and other uses other than semiconductor manufacturing. Then, a high-purity developer such as a polyimide, a resist for a sensor, a resist for a lens or the like, and a rinse liquid can be used. As one of the preferable forms, the drug solution contains an organic solvent. The content of the organic solvent in the chemical liquid is not particularly limited, but generally 97.0 to 99.999 mass% is preferable, and 99.9 to 99.999 mass% is more preferable, with respect to the total mass of the chemical liquid. The organic solvent may be used alone or in combination of two or more. When two or more organic solvents are used in combination, the total content is preferably within the above range.
In the present specification, the term “organic solvent” means a liquid organic compound contained in a content of more than 10000 mass ppm per component with respect to the total mass of the chemical solution. That is, in the present specification, the liquid organic compound contained in an amount of more than 10,000 mass ppm with respect to the total mass of the chemical liquid corresponds to an organic solvent.
In addition, in this specification, a liquid is intended to be a liquid at 25° C. and atmospheric pressure.

The type of the organic solvent is not particularly limited, and known organic solvents can be used. Examples of the organic solvent include alkylene glycol monoalkyl ether carboxylate, alkylene glycol monoalkyl ether, alkyl lactate ester, alkyl alkoxypropionate, cyclic lactone (preferably having 4 to 10 carbon atoms), and monoketone which may have a ring. Examples thereof include compounds (preferably having 4 to 10 carbon atoms), alkylene carbonate, alkyl alkoxyacetate, and alkyl pyruvate.
Moreover, as the organic solvent, for example, those described in JP-A-2016-57614, JP-A-2014-216664, JP-A-2016-138219, and JP-A-2015-135379 may be used. Good.

As the organic solvent, propylene glycol monomethyl ether (PGMM), propylene glycol monoethyl ether (PGME), propylene glycol monopropyl ether (PGMP), propylene glycol monomethyl ether acetate (PGMEA), ethyl lactate (EL), methyl methoxypropionate (MPM), cyclopentanone (CyPn), cyclohexanone (CyHe), γ-butyrolactone (γBL), diisoamyl ether (DIAE), butyl acetate (nBA), isoamyl acetate (iAA), isopropanol (IPA), 4-methyl 2-pentanol (MIBC), dimethyl sulfoxide (DMSO), n-methyl-2-pyrrolidone (NMP), diethylene glycol (DEG), ethylene glycol (EG), dipropylene glycol (DPG), propylene glycol (PG), At least one selected from the group consisting of ethylene carbonate (EC), propylene carbonate (PC), sulfolane, cycloheptanone, and 2-heptanone (MAK) is preferable.

The chemical liquid may contain other components other than the organic solvent. Other components include, for example, metal impurities (metal ions, metal particles), organic impurities, water, and the like.

[Metallic impurities]
The chemical liquid may contain metal impurities (metal particles and metal ions). The definition and measurement method of the metal particles and metal ions are as described above.
The total content of metal impurities contained in the chemical solution is not particularly limited, but is preferably 200 mass ppt or less, more preferably 50 mass ppt or less. The lower limit is not particularly limited, but generally 0.1 mass ppt or more is preferable.

<Metal particles>
The content of the metal particles in the chemical liquid is not particularly limited, but generally 100 mass ppt or less is preferable, 50 mass ppt or less is more preferable, and 30 mass ppt is further preferable, with respect to the total mass of the chemical liquid. The lower limit is not particularly limited, but generally 0.1 mass ppt or more is preferable. The metal particles may be contained alone or in combination of two or more in the liquid medicine. When the chemical liquid contains two or more kinds of metal particles, the total content is preferably within the above range.

(Fe particles)
In particular, when the chemical liquid is used for semiconductor production, the chemical liquid has a more excellent defect suppressing performance by reducing the content of Fe particles, Al particles, Ti particles, Cr particles, and Na particles in the chemical liquid. ..
The content of Fe particles in the chemical solution is not particularly limited, but is preferably 0.020 mass ppb or less, more preferably 10 mass ppt or less. The lower limit is not particularly limited, but generally 0.01 mass ppt or more is preferable.
In the present specification, the Fe particles include not only particles consisting of Fe but also compounds such as oxides and sulfides in which Fe and other non-metal elements are bonded. The same applies to the other particles in the present specification.

(Al particles)
The content of Al particles in the chemical solution is not particularly limited, but is preferably 0.010 mass ppb or less, and more preferably 8.0 mass ppt or less. The lower limit is not particularly limited, but generally 0.01 mass ppt or more is preferable.

(Ti particles)
The content of Ti particles in the chemical liquid is not particularly limited, but is preferably 0.010 mass ppb or less, and more preferably 8.0 mass ppt or less. The lower limit is not particularly limited, but generally 0.01 mass ppt or more is preferable.

(Cr particles)
The content of Cr particles in the chemical solution is not particularly limited, but 0.005 mass ppb or less is preferable, and 3.0 mass ppt or less is more preferable. The lower limit is not particularly limited, but generally 0.01 mass ppt or more is preferable.

(Na particles)
The content of Na particles in the chemical solution is not particularly limited, but is preferably 0.050 mass ppb or less, more preferably 20 mass ppt or less. The lower limit is not particularly limited, but generally 0.01 mass ppt or more is preferable.

<Metal ion>
The content of the metal ion in the chemical liquid is not particularly limited, but generally 100 mass ppt or less is preferable, 50 mass ppt or less is more preferable, and 30 mass ppt or less is further preferable, with respect to the total mass of the chemical liquid. The lower limit is not particularly limited, but generally 1.0 mass ppt or more is preferable. The metal ions may be contained alone or in combination of two or more in the chemical solution. When the chemical solution contains two or more kinds of ionic particles, the total content is preferably within the above range.

In particular, when the chemical solution is used for semiconductor manufacturing, the chemical solution has more excellent defect suppressing performance by reducing the content of Fe ions, Al ions, Ti ions, Cr ions, and Na ions in the chemical solution. ..

(Fe ion)
The content of Fe ions in the chemical solution is not particularly limited, but is preferably 0.010 mass ppb or less, more preferably 8.0 mass ppt or less. The lower limit is not particularly limited, but generally 0.01 mass ppt or more is preferable.
In the present specification, Fe ions include not only ions consisting of Fe but also complex ions. The same applies to the other ions in the present specification.

(Al ion)
The content of Al ions in the chemical solution is not particularly limited, but is preferably 0.010 mass ppb or less, and more preferably 8.0 mass ppt or less. The lower limit is not particularly limited, but generally 0.01 mass ppt or more is preferable.

(Ti ion)
The content of Ti ions in the chemical solution is not particularly limited, but is preferably 0.010 mass ppb or less, and more preferably 8.0 mass ppt or less. The lower limit is not particularly limited, but generally 0.01 mass ppt or more is preferable.

(Cr ion)
The content of Ti ions in the chemical liquid is not particularly limited, but 0.005 mass ppb or less is preferable, and 3.0 mass ppt or less is more preferable. The lower limit is not particularly limited, but generally 0.01 mass ppt or more is preferable.

(Na ion)
The content of Na ions in the chemical solution is not particularly limited, but is preferably 0.050 mass ppb or less, more preferably 20 mass ppt or less. The lower limit is not particularly limited, but generally 0.01 mass ppt or more is preferable.

〔container〕
The drug solution may be temporarily stored in the container until use. The container for storing the above-mentioned drug solution is not particularly limited, and a known container can be used.
As a container for storing the above-mentioned chemical solution, a container having a high degree of cleanliness inside the container and less elution of impurities is preferable for semiconductor applications.
Specific examples of usable containers include, but are not limited to, "Clean Bottle" series manufactured by Aicello Chemical Co., Ltd., "Pure Bottle" manufactured by Kodama Resin Co., Ltd., and the like.

As the container, for the purpose of preventing impurities (contamination) from mixing in the raw materials and the chemical liquid, a multi-layer bottle having an inner wall with a six-layer structure made of six kinds of resins or a seven-layer structure made of six kinds of resins is used. It is also preferable to use. Examples of these containers include the containers described in JP-A-2015-123351.

The liquid contact portion of this container is preferably made of the corrosion resistant material described above.
The inside of the container is preferably washed before containing the solution. The liquid used for cleaning is preferably the above-mentioned chemical liquid itself or a diluted liquid of the above-mentioned chemical liquid. The above-mentioned chemical solution may be transported and stored by bottling in a container such as a gallon bottle or a coated bottle after manufacturing. The gallon bottle may or may not be made of a glass material.

The inside of the container may be replaced with an inert gas (such as nitrogen or argon) having a purity of 99.99995% by volume or higher for the purpose of preventing changes in the components in the solution during storage. Particularly, a gas having a low water content is preferable. Further, at the time of transportation and storage, it may be at room temperature, but in order to prevent deterioration, the temperature may be controlled in the range of -20°C to 30°C.

[Uses of chemicals]
The chemical liquid according to the above embodiment is preferably used for semiconductor manufacturing. Specifically, in a semiconductor device manufacturing process including a lithography process, an etching process, an ion implantation process, and a peeling process, for treating an organic substance after the end of each process or before moving to the next process. It can be used as a pre-wetting liquid, a developing liquid, a rinsing liquid, a stripping liquid and the like. For example, it can be used for rinsing the edge alignment of the semiconductor substrate before and after the resist application.
Further, the above-mentioned chemical liquid can be used as a diluting liquid for the resin contained in the resist liquid (described later). Moreover, you may dilute with another organic solvent and/or water.

Further, the above-mentioned chemicals can be suitably used for other purposes than semiconductor manufacturing, and can also be used as a developing solution for polyimide, a resist for sensors, a resist for lenses and the like, and a rinse solution.
Further, the above-mentioned chemical liquid can be used as a solvent for medical use or cleaning use. In particular, it can be suitably used for cleaning containers, pipes, substrates (for example, wafers, glass, etc.).

[Second Embodiment of Purification Device]
The chemical|medical solution purification apparatus which concerns on the 2nd Embodiment of this invention is demonstrated using FIG. The chemical liquid refining apparatus 70 in FIG. 7 is a refining apparatus in which a distillation column 71 is further connected to a manufacturing tank 61 of the chemical liquid refining apparatus 60 described in FIG. The refining apparatus 70 includes a distillation column 71, and the substance to be purified (for example, a substance to be purified containing an organic solvent) that has flowed in from a pipe line 72 at the bottom of the distillation column 71 is distilled in the distillation column 71, and a pipe line 73 is supplied with F. It flows in the ₀ direction and flows into the manufacturing tank 61. The subsequent steps are as described above.
The liquid contact part of the distillation column 71 is preferably made of a corrosion resistant material. The corrosion resistant material is as described above.

The method for purifying a chemical liquid using the chemical liquid purifying apparatus according to the above embodiment is not particularly limited, but in addition to the chemical liquid purification method already described, it has a distillation step for distilling a substance to be purified using a distillation column. Preferably.

[manufacturing device]
The chemical|medical solution manufacturing apparatus which concerns on embodiment of this invention is equipped with the filter unit already demonstrated. Since the manufacturing apparatus includes the filter unit, it is possible to manufacture a chemical liquid having excellent defect suppressing performance. The chemical liquid manufacturing apparatus according to the above embodiment will be described with reference to FIG.

FIG. 8 is a schematic diagram showing a chemical liquid manufacturing apparatus 80 according to an embodiment of the present invention. The manufacturing apparatus 80 has a reaction section in the front stage of the chemical liquid refining apparatus 70 according to the second embodiment. The reaction section is composed of a reaction tank 81 and a raw material charging device 82, and can react the raw materials to synthesize a substance to be purified containing an organic solvent. The product to be purified containing the organic solvent synthesized in the reaction section flows into the distillation column 71 via the valve 83 and the pipe 72 and is purified by the method already described to produce a chemical solution containing the organic solvent. It
Although the chemical liquid manufacturing apparatus 80 includes the distillation column 71, the chemical liquid manufacturing apparatus according to the embodiment of the present invention is not limited to this, and may not include the distillation column 71. As an example of the chemical liquid manufacturing apparatus that does not include a distillation column, there is a chemical liquid manufacturing apparatus that includes a reaction unit in the preceding stage of the purification device 60 described above.

The material of the liquid contacting part of the reaction part is not particularly limited, but it is preferably formed using the corrosion-resistant material described above from the viewpoint that a chemical liquid having more excellent defect suppressing performance can be obtained.

[Method for manufacturing chemical solution]
The method for producing a chemical liquid containing an organic solvent using the above-mentioned chemical liquid production apparatus is not particularly limited, but preferably has the following steps.
・Reaction process/purification process

<Reaction process>
The reaction step is a step of reacting raw materials to obtain a reaction product which is a substance to be purified.
The reactant is not particularly limited, and examples thereof include a substance to be purified containing an organic solvent contained in the chemical solution. That is, a step of synthesizing an organic solvent to obtain a product to be purified containing the organic solvent can be mentioned.
The method for obtaining the reaction product is not particularly limited, and a known method can be used. For example, there may be mentioned a method of reacting one or more raw materials in the presence of a catalyst to obtain a reaction product.
More specifically, for example, a step of reacting acetic acid and n-butanol in the presence of sulfuric acid to obtain butyl acetate, reacting ethylene, oxygen, and water in the presence of Al(C ₂ H ₅ ) ₃ , A step of obtaining 1-hexanol, a step of reacting cis-4-methyl-2-pentene in the presence of Ipc2BH (Diisopinocampheylborane) to obtain 4-methyl-2-pentanol, propylene oxide, methanol, and acetic acid of sulfuric acid. Reacting in the presence to obtain PGMEA (propylene glycol 1-monomethyl ether 2-acetate), acetone and hydrogen are reacted in the presence of copper oxide-zinc oxide-aluminum oxide to obtain IPA (isopropoxy alcohol) And a step of reacting lactic acid and ethanol to obtain ethyl lactate.

The substance to be purified obtained in the above reaction step is refined to produce a chemical solution. The method for purifying the substance to be purified is as described above.

The present invention will be described in more detail based on the following examples. The materials, usage amounts, ratios, processing contents, processing procedures, and the like shown in the following examples can be appropriately changed without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be limitedly interpreted by the following examples.

[Chemical solution purifier]
The object to be purified containing the organic solvent was purified using the purification apparatus shown in FIG. The manufacturing tank, the pipeline (including the pump and the valve), and the liquid contact portion of the filling device in the refining device were all made of PTFE, PFA, or electropolished SUS (SUS was buffed, and then electropolished. Stuff). The filter unit was prepared by the following method.

<Preparation of filter unit>
The first filter material was prepared by the following method.
(Synthesis of Filter Material Used in Filter Unit of Example 53)
The synthesis was carried out with reference to the literature (H. Egawa, et al., Anal. Sci, 1992, 8, 195-200, and Japanese Patent Publication No. 5-21123).
In a vial, 1 part by mass of pre-synthesized polyglycidyl methacrylate (described as "pGMA" in Table 1) and 1-aza-15-crown 5-ether (described as "T1" in Table 1). After adding 2 parts by mass and 4 parts by mass of propylene glycol monoether and stirring, the mixture was left to stand in an oven at 100° C. for one day. The vial was taken out of the oven, and the obtained polymer was thoroughly washed with methanol and then vacuum dried for one day to obtain a specific polymer having the following units. The reaction formula is shown below.

(Synthesis of Filter Material Used in Filter Unit of Example 54)
A specific polymer was prepared in the same manner as in Example 53 except that dimethyltetraazacyclotetradecane (described as "T2" in Table 1) was used instead of 1-aza-15-crown 5-ether. Got

(Synthesis of Filter Material Used in Filter Unit of Example 55)
Instead of 1-aza-15-crown 5-ether, 1-aza-18-crown 6-ether (described as "T3" in Table 1) was used, and refer to JP-A-2017-39091. Thus, a specific polymer containing a unit represented by the following formula was obtained.

For Examples and Comparative Examples other than the above, the compounds shown below were used to refer to pages 98 to 13 of WO 98/48098, and the like, and polyglycidyl methacrylate (in the table, described as "pGMA"). .) was introduced with a specific substituent to prepare a first filter material. The abbreviations for each compound are as follows.

-EDTA: ethylenediaminetetraacetic acid-NTA: Nitrilo Triacetic Acid
CyDTA: trans-1,2-Diaminocyclohexane-N,N,N′,N′-tetraacetic acid
-DTPA: Diethylethyleneamine-N,N,N',N'',N''-pentaacetic acid
-EDTA-OH: N-(2-Hydroxyethyl)ethylenediamine-N,N',N'-triacetic acid
-GEDTA: O,O'-Bis (2-aminoethyl)ethyleneglycol-N,N,N',N'-tetraacetic acid
-TTHA: Triethylenetamine-N,N,N',N",N"',N"'-hexaacetic acid
・DHEG: Dihydroxyethyl Glycine
・IDA: Iminodiacetic acid
-EDDA: ethylenediamine-N,N'-diacetic acid-DPTA-OH: 1,3-Diamino-2-hydropropane Tetraacetic Acid
-NTP: N-(2-carboxyethyl)iminodiacetic acid-Methyl-EDTA: propylenediamine-N,N,N',N'-tetraacetic acid-HIDA: Hydroxyethyl Imino Diacetic Acid
-EDDP: ethylenediamine-N,N-dipropionic acid-EDTPO: N,N,N',N'-ethylenediaminetetrakis (methylenephosphonic acid)
・NTPO: Nitrilotri (methylphosphonic acid)
-BAPTA: 1,2-bis(o-aminophenoxide)ethane-N,N,N',N'-tetraacetic acid-CA: citric acid

A first filter was manufactured using the first filter material obtained above and housed in the housing shown in Table 1. In addition, a second filter was manufactured using the second filter material and housed in the housing shown in Table 1. Further, a third filter was manufactured using the third filtering material and housed in the housing shown in Table 1.

In addition, the "filter array" in Table 1 represents filters housed in the primary housing to the tertiary housing in order. Further, the material and pore size of each filter material of each filter are shown in the items of "first filter material" to "third filter material".

<Dissolution test>
3000 g of isopropanol (purity: 99.99% by mass, manufactured by FUJIFILM Ultra Pure Solutions) was prepared as a test solvent in a test container having a capacity of 3000 mL and capable of being sealed. The first filter was immersed therein, and the liquid temperature of the test solvent was set to 25° C. and maintained for 48 hours.
Further, a similar test container containing the same amount of the test solvent as above was similarly maintained at 25° C. for 48 hours (blank test).
The content of organic impurities in the test solvent after the immersion was Or ₂ (mass ppt), the content of the organic impurities in the test solvent after the blank test was Or _B (mass ppt), and before and after the immersion by the following method. The amount of increase in the content of organic impurities in the test solvent was calculated.
Increase in the content of formula: organic _{impurities) =} Or 2 -Or _B
The results are shown in Table 1.

In the same manner as above, the increase amount of organic impurities in the test solvent before and after the immersion, the increase amount of metal ions, and the increase amount of metal particles were calculated. Further, a specific test was performed on the second filter and the third filter by the same method, and the increased amounts of the organic solvent, the metal ions, and the metal particles before and after the immersion were measured. The results are shown in Table 1.
The contents of organic impurities, metal ions, and metal particles in the test solvent were measured by the following methods.

(Organic impurities)
A gas chromatograph mass spectrometer (product name "GCMS-2020", manufactured by Shimadzu Corporation, measurement conditions are as follows) was used for the measurement.

(Measurement condition)
Capillary column: InertCap 5MS/NP 0.25 mmI. D. ×30 m df=0.25 μm
Sample introduction method: Split 75 kPa, constant pressure vaporization chamber temperature: 230°C
Column oven temperature: 80°C (2 min)-500°C (13 min) Temperature rising rate 15°C/min
Carrier gas: Helium septum Purge flow rate: 5 mL/min
Split ratio: 25:1
Interface temperature: 250℃
Ion source temperature: 200℃
Measurement mode: Scan m/z=85-500
Sample introduction volume: 1 μL

(Metal particles, metal ions)
An Agilent 8800 Triple Quadrupole ICP-MS (for semiconductor analysis, option #200) was used for the measurement. Based on the measurement results, the contents of metal particles and metal ions were determined.

-Measurement conditions The sample introduction system used a quartz torch, a coaxial PFA (perfluoroalkoxyalkane) nebulizer (for self-priming), and a platinum interface cone. The measurement parameters of the cool plasma condition are as follows.
・RF (Radio Frequency) output (W): 600
・Carrier gas flow rate (L/min): 0.7
・Makeup gas flow rate (L/min): 1
・Sampling depth (mm): 18

[Purification of chemicals]
The products to be purified containing the organic solvents listed in Table 1 were purified using a purification apparatus including the filter units listed in Table 1, respectively. The content (total of metal particles and metal ions) of the metal components (Al, Fe, Ti, Na, and K) before and after purification was measured by the same method as above. The results are shown in Table 1.
In addition, the symbol of each organic solvent in Table 1 represents the following organic solvents.
-PGMM: Propylene glycol monomethyl ether-PGME: Propylene glycol monoethyl ether-PGMP: Propylene glycol monopropyl ether-PGMEA: Propylene glycol monomethyl ether acetate-EL: Ethyl lactate-MPM: Methyl methoxypropionate-CyPn: Cyclopentanone- CyHe: cyclohexanone, γBL: γ-butyrolactone, DIAE: diisoamyl ether, nBA: butyl acetate, iAA: isoamyl acetate, Hexane: hexane, MAK: 2-heptanone, IPA: isopropanol, PGMEA/PGME (v/v=7/ 3): Propylene glycol monomethyl ether acetate/Propylene glycol monoethyl ether (volume ratio 7:3)

[Evaluation of chemical liquid defect suppression performance]
The defect suppressing performance of the chemical liquid purified by using the above-mentioned purification device was evaluated by the following methods, and the results are shown in Table 1.
First, a silicon oxide film substrate having a diameter of 300 mm was prepared.
Next, using an on-wafer surface inspection device (SP-5; manufactured by KLA Tencor), the number of particles having a diameter of 32 nm or more (hereinafter, referred to as “defect”) existing on the substrate was measured (this is referred to as “defect”). Initial value.). Next, the substrate was set on a spin discharge device, and each chemical was discharged onto the surface of the substrate at a flow rate of 1.5 L/min while rotating the substrate. Then, the substrate was spin dried.
Next, the number of defects existing on the substrate after the chemical solution was applied was measured using the above-mentioned device (SP-5) (this is a measured value). Next, the difference between the initial value and the measured value was calculated (measured value-initial value). The obtained results were evaluated based on the following criteria, and the results are shown in Table 1.

"AA": The difference between the initial value of the number of defects and the measured value was less than 100.
"A": The difference between the initial value of the number of defects and the measured value exceeded 100 and was 300 or less.
"B": The difference between the initial value and the measured value of the number of defects exceeded 300 and was 500 or less.
"C": The difference between the measured value of the number of defects and the initial value exceeded 500 and was 1000 or less.
“D”: The difference between the measured value of the number of defects and the initial value exceeded 1000 and was 2000 or less.
"E": The difference between the measured value of the number of defects and the initial value exceeded 2000.

Table 1 shows the arrangement of filters in each filter unit, the result of the elution test of each filter, the content of metal components in the substance to be purified, the content of metal components in the chemical liquid, and the defect suppression performance of the chemical liquid. <Part 1> (1) to Table 1 <Part 1> (5).
For example, in the first embodiment, the filter unit has a first housing (where the first filter is stored) and a second housing (where the second filter is stored) from the primary side. Further, the first filter material of the first filter is made of pGMA having a specific substituent, Methyl-EDTA (coordination number 6, chelate ring member 6), and has a pore diameter of 15 nm. Chelate stability constant of the first filter media, 14.2 against ^{Al 3+} ions, 16.8 against ^{Fe 3+} ions, 13.0 respect ^{Ti 3+} ions, relative to Na ⁺ ions 6.7 , 5.6 for K ⁺ ions. The second filter material of the second filter is made of Nyron and has a pore size of 3 nm. In addition, as an increase amount of each component in the test solvent after the elution test of the first filter and the second filter, an organic impurity, a metal ion, and a metal particle are in the order of 300 mass ppt, 10.2. The mass is ppt, 8.2 mass ppt, and the second filter is 285 mass ppt, 8.5 mass ppt, 6.5 mass ppt. The substance to be purified is CyHe, and the contents of Al, Fe, Ti, Na, and K in the substance to be purified are 5.5 mass ppt, 8.2 mass ppt, and 4.9 mass, respectively. ppt, 6.6 mass ppt, and 3.6 mass ppt, and the respective contents in the chemical solution obtained after purification using the filter unit are 1.8 mass ppt, 1.6 mass ppt, It is 0.8 mass ppt, 1.3 mass ppt, and 0.9 mass ppt, and shows that the defect suppression performance of a chemical|medical solution is AA. The same applies to each Example and Comparative Example other than the above. In addition, after Example 34, it describes in each line of Table 1 <part 2> (1)-Table 1 <part 2> (5), and after Example 67, it describes in table 1 <part 3> (1)-table. 1 <No. 3> Described in each line of (5).

From the results shown in Table 1, the chemical liquid purified using the purification device including the filter unit described in each example had the effect of the present invention. On the other hand, the chemical liquid purified using the purification device including the filter unit described in each comparative example did not have the effect of the present invention.
From the results shown in Table 1, the chemical liquid purified using the purification device including the filter unit of Example 1, in which the pore size of the filter medium (second filter medium) included in the second filter is 1.0 to 15 nm, It had a more excellent defect suppressing performance as compared with the chemicals purified by using the purifying apparatus including the filter units of Examples 18 and 19.
From the results shown in Table 1, the chemical liquid purified using the purification device including the filter unit of Example 1 in which the pore size of the filter medium (first filter medium) included in the first filter is 10 to 100 nm is It had more excellent defect suppressing performance as compared with the chemical liquid purified by using the purification device including 32 filter units.
From the results shown in Table 1, the filter of Example 1 in which the substituent contained in the polymer contained in the filter material included in the first filter has 5 or more ring members in the chelate ring formed by combining with the metal atom. The chemical liquid purified using the purification device including the unit had a more excellent defect suppressing performance as compared with the chemical liquid of Example 33.
From the results shown in Table 1, the chemical liquid purified by using the purification device including the filter unit in which the first housing is arranged on the primary side and the second housing is arranged on the secondary side is the same as that of the filter unit of Example 63. It had more excellent defect suppressing performance as compared with the chemical liquid purified using the purification device provided.

10 Filter 11 Filtering Material 12 Core 13 Cap 14 Liquid Outlet 20 Housing 21 Lid 22 Body 23, 43, 47, 52 Liquid Inlet 24, 44, 48, 53 Liquid Outlet 25, 26 Internal Pipeline 40, 50 Filter Unit 41 (A), 41(b), 41(c), 41(d) Pipe line 42 Primary housing 46 Secondary housing 51 Tertiary housing 60, 70 Purification device 61 Manufacturing tank 62, 72, 73 Pipe line 63, 65, 83 Valve 64 Pump 66 Filling device 71 Distillation column 80 Manufacturing device 81 Reaction tank 82 Raw material charging device

Claims (23)

In the pipeline to which the substance to be purified is supplied, they are arranged independently of each other,
A first housing containing a first filter provided with a filter material containing a first polymer having a multidentate coordinating group,
A second filter containing a second polymer having at least one bond selected from the group consisting of an amide bond, an imide bond, and an ester bond, and having a second filter provided with a filter medium having a pore size of 50 nm or less. Two housings,
And a filter unit. The filter unit according to claim 1, wherein the second polymer is nylon. The filter unit according to claim 1 or 2, wherein the first housing is arranged on the primary side, and the second housing is arranged on the secondary side. The filter unit according to any one of claims 1 to 3, wherein the chelate stability constant of the substituent satisfies at least one requirement selected from the group consisting of (A) to (E) below.
(A) more than 4.5 for Al ³⁺ ions (B) more than 8.0 for Fe ³⁺ ions (C) more than 4.5 for Ti ³⁺ ions (D) for Na ⁺ ions Above 3.0 for (E)K ⁺ ions 5. The substituent according to claim 1, wherein the substituent is a group derived from at least one compound selected from the group consisting of compounds represented by the following formulas (1) to (3). Filter unit.

In formula (1), X ₁ represents a hydrogen atom, a carboxy group or a phosphonium group, L ₁ represents a single bond or a divalent linking group, n represents an integer of 1 or more, and 2 or more L's are present. ₁ and X ₁ may be the same or different, but not all X ₁ are hydrogen atoms at the same time.
In formula (2), X ₂ represents a hydrogen atom, a carboxy group or a phosphonium group, and A represents a divalent linking group having a hydroxy group. n represents 2.
In formula (3), n1 to n5 each independently represent an integer of 1 to 5, and R _{1 to} R ₃ each independently consist of an oxygen atom, a group represented by —NX—, and a sulfur atom. Represents one selected from the group, and X represents a hydrogen atom or a monovalent organic group. The filter unit according to any one of claims 1 to 4, wherein the number of ring members of the chelate ring formed by combining the substituent with a metal atom is 5 or more. The filter unit according to any one of claims 1 to 6, wherein the chelate stability constant of the substituent satisfies at least one requirement selected from the group consisting of the following (F) to (J).
(F) is 6.0 to 20 for Al ³⁺ ions, and is more than 8.0 for (G)Fe ³⁺ ions, and is 6.0 or less for 20 or less (H)Ti ³⁺ ions. It is 6.0 to 20 for certain (I)Na ⁺ ions and 6.0 to 20 for (J)K ⁺ ions. The filter unit according to any one of claims 1 to 7, which is used to purify a chemical liquid for semiconductor production. The filter unit according to any one of claims 1 to 8, wherein the first polymer having a multidentate substituent has a unit represented by the following formula (P-1).

In formula (P-1), R _p represents a hydrogen atom, a halogen atom, or a monovalent organic group, W represents the substituent, and L _p represents —O— or —C(═O)—. , _-NR 4 _{R 5} -, a phenylene group, and,, _-CR 6 _{R 7} -, and represents at least one member selected from the group consisting _{of, R 4, R 5, R} 6 and,, R ₇ independently represents a hydrogen atom or a monovalent organic group. The filter unit according to any one of claims 1 to 9, wherein the first filter satisfies requirement 1 in the following test.
Test: Under the condition that the mass ratio of the mass of the first filter to the mass of the test solvent containing 99.99 mass% or more of isopropanol is 1.0 when the liquid temperature of the test solvent is 25°C. The first filter is immersed in the test solvent having a liquid temperature of 25° C. for 48 hours.
Requirement 1: When one kind of organic impurities is contained in the test solvent after immersion, the amount of increase of the one kind of organic impurities before and after the immersion is 1000 mass ppm or less, and the test solvent after immersion is 2 When one or more kinds of organic impurities are contained, the total amount of increase of the two or more kinds of organic impurities before and after the immersion is 1000 mass ppm or less. The filter unit according to any one of claims 1 to 10, wherein the first filter satisfies requirement 2 in the following test.
Test: Under the condition that the mass ratio of the mass of the first filter to the mass of the test solvent containing 99.99 mass% or more of isopropanol is 1.0 when the liquid temperature of the test solvent is 25°C. The first filter is immersed in the test solvent having a liquid temperature of 25° C. for 48 hours.
Requirement 2: When one kind of metal ion is contained in the test solvent after immersion, the amount of increase of the one kind of metal ion before and after immersion is 100 mass ppm or less, and the test solvent after immersion is 2 When one or more kinds of metal ions are contained, the total amount of increase of the two or more kinds of metal ions before and after the immersion is 100 mass ppm or less. The filter unit according to claim 1, wherein the first filter satisfies requirement 3 in the following test.
Test: Under the condition that the mass ratio of the mass of the first filter to the mass of the test solvent containing 99.99 mass% or more of isopropanol is 1.0 when the liquid temperature of the test solvent is 25°C. The first filter is immersed in the test solvent having a liquid temperature of 25° C. for 48 hours.
Requirement 3: When one type of metal particles is contained in the test solvent after immersion, the increase amount of the one type of metal particles before and after immersion is 100 mass ppm or less, and 2 in the test solvent after immersion. When one or more kinds of metal particles are contained, the total amount of increase of the two or more kinds of metal particles before and after the immersion is 100 mass ppm or less. The filter unit according to any one of claims 1 to 12, wherein the filter medium included in the first filter has a pore size of 10 to 100 nm. The filter unit according to claim 1, wherein the second filter satisfies requirement 4 in the following test.
Test: Under the condition that the mass ratio of the mass of the second filter to the mass of the test solvent containing 99.99 mass% or more of isopropanol is 1.0 when the liquid temperature of the test solvent is 25°C. The second filter is immersed in a test solvent having a liquid temperature of 25° C. for 48 hours.
Requirement 4: When one kind of organic impurities is contained in the test solvent after immersion, the amount of increase of the one kind of organic impurities before and after the immersion is 1000 mass ppm or less, and the test solvent after immersion has 2 When one or more kinds of organic impurities are contained, the total amount of increase of the two or more kinds of organic impurities before and after the immersion is 1000 mass ppm or less. The filter unit according to claim 1, wherein the second filter satisfies requirement 5 in the following test.
Test: Under the condition that the mass ratio of the mass of the second filter to the mass of the test solvent containing 99.99 mass% or more of isopropanol is 1.0 when the liquid temperature of the test solvent is 25°C. The second filter is immersed in the test solvent having a liquid temperature of 25° C. for 48 hours.
Requirement 5: When the test solvent after immersion contains one type of metal ion, the amount of increase of the one type of metal ion before and after immersion is 100 mass ppm or less, and the test solvent after immersion contains 2 When one or more kinds of metal ions are contained, the total amount of increase of the two or more kinds of metal ions before and after the immersion is 100 mass ppm or less. The filter unit according to claim 1, wherein the second filter satisfies requirement 6 in the following test.
Test: Under the condition that the mass ratio of the mass of the second filter to the mass of the test solvent containing 99.99 mass% or more of isopropanol is 1.0 when the liquid temperature of the test solvent is 25°C. The second filter is immersed in a test solvent having a liquid temperature of 25° C. for 48 hours.
Requirement 6: When one kind of metal particles is contained in the test solvent after immersion, the amount of increase of the one kind of metal particles before and after immersion is 100 mass ppm or less, and two kinds in the test solvent after immersion. When the above metal particles are contained, the total amount of increase before and after the immersion of the two or more kinds of metal particles is 100 mass ppm or less. The filter unit according to any one of claims 1 to 16, wherein a pore size of a filter medium included in the second filter is 1.0 to 15 nm. Both the filter medium included in the first filter and the filter medium included in the second filter accommodate a third filter including a filter medium in which at least one selected from the group consisting of material and pore size is different. The filter unit according to any one of claims 1 to 17, further comprising a third housing. The pore size of the filter medium included in the third filter is larger than the pore size of the filter medium included in the first filter, and the third housing is arranged further on the primary side than the first housing. The described filter unit. The first polymer having a polydentate substituent has nylon having a polydentate substituent, polyethylene having a polydentate substituent, and a polydentate substituent. The filter unit according to any one of claims 1 to 19, which is at least one selected from the group consisting of a poly(meth)acrylate having and a polyfluorocarbon having a polydentate substituent. A chemical liquid refining apparatus comprising the filter unit according to claim 1. A chemical|medical solution manufacturing apparatus provided with the filter unit as described in any one of Claims 1-21. A chemical solution containing an organic solvent, which is purified by using the filter unit according to claim 1.
The organic solvent is propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monomethyl ether acetate, ethyl lactate, methyl methoxypropionate, cyclopentanone, cyclohexanone, γ-butyrolactone, diisoamyl ether, Butyl acetate, isoamyl acetate, isopropanol, 4-methyl-2-pentanol, dimethyl sulfoxide, n-methyl-2-pyrrolidone, diethylene glycol, ethylene glycol, dipropylene glycol, propylene glycol, ethylene carbonate, propylene carbonate, sulfolane, cyclohepta A drug solution, which is at least one selected from the group consisting of non- and 2-heptanone.