JP2015163662A - Nonionic fluorine-containing surfactant and method of producing the same, and fluorine resin dispersant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a novel nonionic fluorine-containing surfactant that has excellent surface tension reduction ability, is low in bioaccumulation, and exhibits excellent environmental adaptability.SOLUTION: Selected is a nonionic fluorine-containing surfactant synthesized with a carboxylic acid halide having a nitrogen-containing perfluoroalkyl group and an alcohol as raw material.

Description

  The present invention relates to a nonionic fluorine-containing surfactant, a method for producing the same, and a fluororesin dispersant.

  The fluorine-containing surfactant is a surfactant obtained by substituting hydrogen in the alkyl chain with fluorine, and is generally known to be superior in surface tension reducing ability than a surfactant not containing fluorine. This fluorine-containing surfactant is used as an additive for coating liquids in the fields of resins, optical materials, paints, and the like for the purpose of imparting smoothness to the coating film surface. Thereby, defects such as streaks, unevenness, repelling and non-wetting that occur in the coating process are suppressed. Further, it is also used in the field of electronic materials such as semiconductors as an additive for improving wettability, permeability, leveling property, and surface functionality.

  As such a fluorosurfactant, those containing a perfluoroalkyl group having 8 or more carbon atoms have been used. However, in recent years, compounds having a perfluoroalkyl group having 8 or more carbon atoms can be decomposed to produce perfluorooctane sulfonic acid (PFOS) or perfluoroctanic acid (PFOA) having high toxicity and high environmental / bioaccumulation potential. Therefore, there has been a problem that its use is being restricted. Therefore, in the market, there has been a demand for a material having a structure of a perfluoroalkyl group having a carbon number of 6 or less and a short chain length as much as possible, which cannot generate PFOS or PFOA with high environmental and biological accumulation. . However, the actual situation is that conventional materials having a perfluoroalkyl group having 6 or less carbon atoms have not sufficiently exhibited characteristics such as surface tension lowering ability and dispersibility of fluororesin.

  As an example of a fluorosurfactant that does not contain PFOS and PFOA, Patent Document 1 discloses a nonionic fluorosurfactant having a perfluoropropene trimer. However, although the nonionic fluorine-containing surfactant described in Patent Document 1 is branched, the perfluoroalkyl group has 9 carbon atoms, and there is a concern that toxicity and bioaccumulation are still high. Therefore, there is a demand for a fluorosurfactant composed of a perfluoroalkyl group having a smaller number of carbon atoms, in which bioaccumulation is not a problem.

Japanese Patent No. 4772387

  The present invention has been made in view of the above circumstances, and does not contain a perfluoroalkyl group having 8 or more carbon atoms, and there is a concern of generating PFOS or PFOA, which is problematic in terms of bioaccumulation and environmental adaptability. It is an object of the present invention to provide a novel nonionic fluorine-containing surfactant having an excellent surface tension reducing ability while having no chemical structure.

It is another object of the present invention to provide a production method capable of synthesizing the nonionic fluorine-containing surfactant with a simple method with a high yield.
It is another object of the present invention to provide a fluororesin dispersant capable of uniformly dispersing fluororesin fine particles in water.

上記式（１）中、Ｒｆ^１及びＲｆ^２は、それぞれ同一または互いに異なる炭素数１〜６のペルフルオロアルキル基であって、直鎖状又は分枝状であってもよい。また、上記Ｒｆ^１及びＲｆ^２は、直接結合して環状を形成していても良いし、酸素原子または窒素原子を介して結合し、複素環を形成していてもよい。さらに、Ｒｆ^３は、炭素数１〜６のペルフルオロアルキレン基であって、直鎖状又は分枝状であってもよい。
また、上記式（１）中、Ｒ^１は、水素原子またはメチル基である。また、Ｒ^２は、炭素数１〜８の直鎖状または分枝鎖状のアルキル基である。さらに、ｎは、３〜５０の整数である。
［２］ 上記式（１）中、Ｒ^１が水素原子であることを特徴とする前項［１］に記載のノニオン系含フッ素界面活性剤。
［３］ 上記式（１）中、Ｒ^２がメチル基であることを特徴とする前項［１］又は［２］に記載のノニオン系含フッ素界面活性剤。
［４］ 下記一般式（２）で示される窒素原子を含むペルフルオロ複素環を有することを特徴とする前項［１］に記載のノニオン系含フッ素界面活性剤。

上記式（２）中、Ｒｆ^４、Ｒｆ^５及びＲｆ^６は、それぞれ同一または互いに異なる炭素数１〜６のペルフルオロアルキレン基であって、直鎖状又は分枝状であってもよい。Ｘは、酸素原子、窒素原子又はＣＦ_２基である。
また、上記式（２）中、Ｒ^３は、水素原子またはメチル基である。また、Ｒ^４は、炭素数１〜８の直鎖状または分枝鎖状のアルキル基である。さらに、ｎは、３〜５０の整数である。
［５］ 上記式（２）中、Ｒ^３が水素原子であることを特徴とする前項［４］に記載のノニオン系含フッ素界面活性剤。
［６］ 上記式（２）中、Ｒ^４がメチル基であることを特徴とする前項［４］又は［５］に記載のノニオン系含フッ素界面活性剤。
［７］ 下記一般式（３）で示される直鎖状のペルフルオロアルキル基を有することを特徴とする前項［１］に記載のノニオン系含フッ素界面活性剤。

上記式（３）中、ｍ及びｎは、それぞれ同一又は互いに異なる１〜６の整数である。また、Ｒｆ^７は、炭素数１〜６のペルフルオロアルキレン基であって、直鎖状又は分枝状であってもよい。
また、上記式（３）中、Ｒ^５は、水素原子またはメチル基である。また、Ｒ^６は、炭素数１〜８の直鎖状または分枝鎖状のアルキル基である。さらに、ｎは、３〜５０の整数である。
［８］ 上記式（３）中、Ｒ^５が水素原子であることを特徴とする前項［７］に記載のノニオン系含フッ素界面活性剤。
［９］ 上記式（３）中、Ｒ^６がメチル基であることを特徴とする前項［７］又は［８］に記載のノニオン系含フッ素界面活性剤。
［１０］ 前項［１］に記載のノニオン系含フッ素界面活性剤の製造方法であって、
下記一般式（４）で示される含窒素ペルフルオロアルキル基を有するカルボン酸ハロゲン化物と、下記一般式（５）で示されるアルコールと、を原料として用いることを特徴とするノニオン系含フッ素界面活性剤の製造方法。

上記式（４）中、Ｒｆ^１及びＲｆ^２は、それぞれ同一または互いに異なる炭素数１〜６のペルフルオロアルキル基であって、直鎖状又は分枝状であってもよい。また、上記Ｒｆ^１及びＲｆ^２は、直接結合して環状を形成していても良いし、酸素原子または窒素原子を介して結合し、複素環を形成していてもよい。また、Ｒｆ^３は、炭素数１〜６のペルフルオロアルキレン基であって、直鎖状又は分枝状であってもよい。さらに、Ｙは、フッ素、塩素、臭素及びヨウ素からなる群から選択されるいずれか１のハロゲン原子である。

上記式（５）中、Ｒ^１は、水素原子またはメチル基である。また、Ｒ^２は、炭素数１〜８の直鎖状または分枝鎖状のアルキル基である。さらに、ｎは、３〜５０の整数である。
［１１］ 上記一般式（４）で示される含窒素ペルフルオロアルキル基を有するカルボン酸ハロゲン化物と上記一般式（５）で示されるアルコールとを、非プロトン性溶媒中において、塩基存在下で反応させることを特徴とする前項［１０］に記載のノニオン系含フッ素界面活性剤の製造方法。
［１２］ 上記非プロトン性溶媒が、アセトニトリル、トルエン、ベンゼン、ジエチルエーテル、ジイソプロピルエーテル、テトラヒドロフラン、クロロホルム、ジクロロメタン、ジメチルスルホキシド、ジメチルホルムアミド及びこれらの任意の混合物からなる群から選択される溶媒であることを特徴とする前項［１１］に記載のノニオン系含フッ素界面活性剤の製造方法。
［１３］ 前記塩基が、ＭＦ、ＭＯＨ、Ｍ_２ＣＯ_３、ＭＨＣＯ_３、アミン、アンモニアからなる群から選ばれた化合物のいずれか一種、又はこれらの任意の混合物からなる群から選択される塩基であることを特徴とする前項［１１］又は［１２］に記載のノニオン系含フッ素界面活性剤の製造方法。ただし上記Ｍは、Ｎａ、Ｋ、Ｌｉ、アンモニウムカチオンのいずれか一種である。
［１４］ 上記式（５）中、Ｒ^１が水素原子であることを特徴とする前項［１０］乃至［１３］のいずれか一項に記載のノニオン系含フッ素界面活性剤の製造方法。
［１５］ 上記式（５）中、Ｒ^２がメチル基であることを特徴とする前項［１０］乃至［１４］のいずれか一項に記載のノニオン系含フッ素界面活性剤の製造方法。
［１６］ 前項［１］に記載のノニオン系含フッ素界面活性剤を含むことを特徴とするフッ素樹脂分散剤。 In order to solve the above problems, the present invention employs the following configuration.
[1] A nonionic fluorine-containing surfactant represented by the following general formula (1).

In the above formula (1), Rf ¹ and Rf ² are the same or different C 1-6 perfluoroalkyl groups, and may be linear or branched. Rf ¹ and Rf ² may be directly bonded to form a ring, or may be bonded through an oxygen atom or a nitrogen atom to form a heterocyclic ring. Further, Rf ³ is a C 1-6 perfluoroalkylene group, and may be linear or branched.
Moreover, in said formula (1), R < ¹ > is a hydrogen atom or a methyl group. R ² is a linear or branched alkyl group having 1 to 8 carbon atoms. Furthermore, n is an integer of 3-50.
[2] The nonionic fluorine-containing surfactant according to [1], wherein R ¹ in formula (1) is a hydrogen atom.
[3] The nonionic fluorine-containing surfactant as described in [1] or [2] above, wherein in the formula (1), R ² is a methyl group.
[4] The nonionic fluorine-containing surfactant according to [1] above, which has a perfluoroheterocycle containing a nitrogen atom represented by the following general formula (2).

In the above formula (2), Rf ⁴ , Rf ⁵ and Rf ⁶ are the same or different perfluoroalkylene groups having 1 to 6 carbon atoms, and may be linear or branched. X is an oxygen atom, a nitrogen atom or a CF ₂ group.
In the above formula (2), R ³ is a hydrogen atom or a methyl group. R ⁴ is a linear or branched alkyl group having 1 to 8 carbon atoms. Furthermore, n is an integer of 3-50.
[5] The nonionic fluorine-containing surfactant according to [4], wherein R ³ is a hydrogen atom in the above formula (2).
[6] The nonionic fluorine-containing surfactant according to [4] or [5] above, wherein in the formula (2), R ⁴ is a methyl group.
[7] The nonionic fluorine-containing surfactant according to [1] above, which has a linear perfluoroalkyl group represented by the following general formula (3).

In the above formula (3), m and n are the same or different integers of 1 to 6, respectively. Rf ⁷ is a perfluoroalkylene group having 1 to 6 carbon atoms, and may be linear or branched.
In the above formula (3), R ⁵ is a hydrogen atom or a methyl group. R ⁶ is a linear or branched alkyl group having 1 to 8 carbon atoms. Furthermore, n is an integer of 3-50.
[8] The nonionic fluorine-containing surfactant as described in [7] above, wherein in formula (3), R ⁵ is a hydrogen atom.
[9] The nonionic fluorine-containing surfactant according to [7] or [8] above, wherein in the formula (3), R ⁶ is a methyl group.
[10] A method for producing the nonionic fluorine-containing surfactant according to [1] above,
Nonionic fluorine-containing surfactant, characterized by using a carboxylic acid halide having a nitrogen-containing perfluoroalkyl group represented by the following general formula (4) and an alcohol represented by the following general formula (5) as raw materials Manufacturing method.

In the above formula (4), Rf ¹ and Rf ² are the same or different C 1-6 perfluoroalkyl groups, and may be linear or branched. Rf ¹ and Rf ² may be directly bonded to form a ring, or may be bonded through an oxygen atom or a nitrogen atom to form a heterocyclic ring. Rf ³ is a C 1-6 perfluoroalkylene group, and may be linear or branched. Further, Y is any one halogen atom selected from the group consisting of fluorine, chlorine, bromine and iodine.

In said formula (5), R < ¹ > is a hydrogen atom or a methyl group. R ² is a linear or branched alkyl group having 1 to 8 carbon atoms. Furthermore, n is an integer of 3-50.
[11] A carboxylic acid halide having a nitrogen-containing perfluoroalkyl group represented by the general formula (4) is reacted with an alcohol represented by the general formula (5) in the presence of a base in an aprotic solvent. The method for producing a nonionic fluorine-containing surfactant as described in [10] above.
[12] The aprotic solvent is a solvent selected from the group consisting of acetonitrile, toluene, benzene, diethyl ether, diisopropyl ether, tetrahydrofuran, chloroform, dichloromethane, dimethyl sulfoxide, dimethylformamide, and any mixture thereof. The method for producing a nonionic fluorine-containing surfactant as described in [11] above.
[13] The base is a base selected from the group consisting of any one of compounds selected from the group consisting of MF, MOH, M ₂ CO ₃ , MHCO ₃ , amine, ammonia, or any mixture thereof. The method for producing a nonionic fluorine-containing surfactant as described in [11] or [12] above, wherein However, said M is any one of Na, K, Li, and an ammonium cation.
[14] The method for producing a nonionic fluorine-containing surfactant according to any one of [10] to [13], wherein R ¹ in formula (5) is a hydrogen atom.
[15] The method for producing a nonionic fluorine-containing surfactant according to any one of [10] to [14], wherein R ² is a methyl group in the formula (5).
[16] A fluororesin dispersant comprising the nonionic fluorine-containing surfactant according to [1].

  The nonionic fluorine-containing surfactant of the present invention has an excellent surface tension reducing ability and has no linear perfluoroalkyl group having 8 or more carbon atoms, so has low bioaccumulation and environmental adaptability. In addition, it is a novel nonionic fluorine-containing surfactant.

Moreover, the manufacturing method of the nonionic fluorine-containing surfactant of this invention can synthesize | combine the said nonionic fluorine-containing surfactant with a yield with a simple method.
Furthermore, the fluororesin dispersant of the present invention can uniformly disperse fluororesin fine particles in water.

  Hereinafter, a nonionic fluorine-containing surfactant which is an embodiment to which the present invention is applied will be described in detail together with a production method thereof and a fluororesin dispersant containing the main component.

<Nonionic fluorine-containing surfactant>
First, the structure of the nonionic fluorine-containing surfactant of this embodiment will be described.
The nonionic fluorine-containing surfactant of this embodiment can be represented by the following general formula (1).

In the above formula (1), Rf ¹ and Rf ² are the same or different C 1-6 perfluoroalkyl groups, and may be linear or branched. Rf ¹ and Rf ² may be directly bonded to form a ring, or may be bonded through an oxygen atom or a nitrogen atom to form a heterocyclic ring.
Rf ³ is a C 1-6 perfluoroalkylene group, and may be linear or branched.

Moreover, in said formula (1), R < ¹ > is a hydrogen atom or a methyl group. R ² is a linear or branched alkyl group having 1 to 8 carbon atoms. Furthermore, n is an integer of 3-50, and it is preferable to set it as the range of 4-30. Here, by setting n to a large value, more polyether structure can be added to one molecule of the nonionic fluorine-containing surfactant represented by the above formula (1) (that is, hydrophilicity). More soluble ethylene oxide groups can be added), so that the solubility in an aqueous solvent can be improved. On the other hand, when n is set to a large value, the molecular weight of the nonionic fluorine-containing surfactant represented by the above formula (1) increases, and the fluorine content per unit amount decreases. End up. Therefore, it is preferable to appropriately select the value of n according to the purpose of use.

  Examples of the nonionic fluorine-containing surfactant represented by the above formula (1) include those having a perfluoroheterocycle represented by the following general formula (2) and a perfluoroamine structure represented by the following formula (3) And the like.

Here, in the above formula (2), Rf ⁴ , Rf ⁵ and Rf ⁶ are the same or different C 1-6 perfluoroalkylene groups, and may be linear or branched. . Moreover, n is an integer of 3-50. X is an oxygen atom, a nitrogen atom or a CF ₂ group.
In the above formula (2), R ³ is a hydrogen atom or a methyl group. R ⁴ is a linear or branched alkyl group having 1 to 8 carbon atoms. Furthermore, n is an integer of 3-50.

In the above formula (3), m and n are the same or different integers of 1 to 6, respectively. Rf ⁷ is a perfluoroalkylene group having 1 to 6 carbon atoms, and may be linear or branched. Furthermore, n is an integer of 3-50.
In the above formula (3), R ⁵ is a hydrogen atom or a methyl group. R ⁶ is a linear or branched alkyl group having 1 to 8 carbon atoms. Furthermore, n is an integer of 3-50.

Specific examples of the nonionic fluorine-containing surfactant represented by the above formula (2) include those having perfluoropiperidine, perfluoropyrrolidine, perfluoropiperazine, perfluoromorpholine, perfluorohexamethyleneimine as the perfluoroheterocycle.
More specifically, for example, structures represented by the following formulas (6) to (13) (provided that the structure includes up to the “—CO—” portion) can be given.

  In addition, specific examples of the nonionic fluorine-containing surfactant represented by the above formula (3) include, for example, structures represented by the following formulas (14) to (23) (however, up to the “—CO—” portion). Structure).

  Moreover, as a structure after the "-CO-" part of the nonionic fluorine-containing surfactant represented by the above formulas (1) to (3), specifically, for example, the following formulas (24) to ( 38).

Here, as a nonionic fluorine-containing surfactant represented by the above formulas (1) to (3), R ² , R ⁴ and R ⁶ shown in the above formulas (1) to (3) are methyl groups. (That is, the structure of the above formula (24) and the above formula (32)) is preferable, and R ¹ , R ³ and R ⁵ are more preferably hydrogen (that is, the structure of the above formula (24)). preferable.

  The nonionic fluorine-containing surfactant of the present embodiment is a leveling agent for obtaining leveling properties of paints and inks, floor waxes using aqueous solvents or organic solvents, emulsion polymerization agents of fluororesins, or usually acidic Additives for plating solutions and etching solutions, resin modifiers for improving resin properties due to high dispersibility, coating additions for imparting releasability, antistatic performance, antifouling, rust prevention, and bactericidal functions Agents, surface treatment agents, cleaning agents and fiber treatment agents with high permeability, fire extinguishing agents, agricultural film antifogging agents, wetting agents, lubricants, adhesives, semiconductor manufacturing processes, liquid crystals, various magnetic disks, optical materials It can use suitably for uses, such as manufacturing processes.

  In addition, when using for the said use, it does not specifically limit about the solvent which can use a nonionic fluorine-containing surfactant, Organic solvents other than aqueous solution may be sufficient. Examples of the organic solvent include alcohols such as methanol and ethanol, ester solvents such as ethyl acetate, ketone solvents such as acetone, aromatic hydrocarbon solvents such as toluene, and hydrocarbon solvents such as hexane. In addition, the aqueous solution can exhibit excellent surface activity even if the pH is in any of acidic, neutral and basic ranges.

  Moreover, when using for the said use, the nonionic fluorine-containing surfactant of this embodiment may be used by 1 type, and may be used together by 2 or more types. Furthermore, you may use as a mixture with components other than a nonionic fluorine-containing surfactant.

  The nonionic fluorine-containing surfactant of the present embodiment does not have a linear perfluoroalkyl group having 8 or more carbon atoms that causes a problem of bioaccumulation. Further, since the nonionic fluorine-containing surfactant of the present embodiment has a structure having a heteroatom, an effect of being easily decomposed is obtained as compared with a perfluoroalkyl group-containing compound whose main skeleton is formed only from carbon. It is done.

<Method for producing nonionic fluorine-containing surfactant>
Next, the manufacturing method of the nonionic fluorine-containing surfactant of this embodiment will be described.
The production method of the nonionic fluorine-containing surfactant of the present embodiment comprises a carboxylic acid halide having a nitrogen-containing perfluoroalkyl group represented by the following general formula (4) and an alcohol represented by the following general formula (5): The reaction is carried out in the presence of a base in an aprotic solvent.

上記式（４）中、Ｒｆ^１及びＲｆ^２は、それぞれ同一または互いに異なる炭素数１〜６のペルフルオロアルキル基であって、直鎖状又は分枝状であってもよい。また、上記Ｒｆ^１及びＲｆ^２は、直接結合して環状を形成していても良いし、酸素原子または窒素原子を介して結合し、複素環を形成していてもよい。また、Ｒｆ^３は、炭素数１〜６のペルフルオロアルキレン基であって、直鎖状又は分枝状であってもよい。さらに、Ｙは、フッ素、塩素、臭素及びヨウ素からなる群から選択されるいずれか１のハロゲン原子である。

In the above formula (4), Rf ¹ and Rf ² are the same or different C 1-6 perfluoroalkyl groups, and may be linear or branched. Rf ¹ and Rf ² may be directly bonded to form a ring, or may be bonded through an oxygen atom or a nitrogen atom to form a heterocyclic ring. Rf ³ is a C 1-6 perfluoroalkylene group, and may be linear or branched. Further, Y is any one halogen atom selected from the group consisting of fluorine, chlorine, bromine and iodine.

上記式（５）中、Ｒ^１は、水素原子またはメチル基である。
また、Ｒ^２は、炭素数１〜８の直鎖状または分枝鎖状のアルキル基である。具体的には、例えば、メチル基、エチル基、プロピル基、イソプロピル基、ブチル基、イソブチル基、ヘキシル基、２−エチルヘキシル基等が挙げられる。
さらに、ｎは、３〜５０の整数である。

In said formula (5), R < ¹ > is a hydrogen atom or a methyl group.
R ² is a linear or branched alkyl group having 1 to 8 carbon atoms. Specific examples include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a hexyl group, and a 2-ethylhexyl group.
Furthermore, n is an integer of 3-50.

  The carboxylic acid halide having a nitrogen-containing perfluoroalkyl group represented by the above formula (4) can be obtained, for example, by electrolytic fluorination of the corresponding carboxylic acid ester or halide in hydrogen fluoride. Moreover, when using what said Y is halogen atoms other than a fluorine atom, for example, the carboxylic acid fluoride which has the perfluoroalkyl group obtained by the said electrolytic fluorination is hydrolyzed, and corresponding carboxylic acid is used. After formation, a suitable halogenating agent (eg thionyl chloride, oxalyl chloride, phosphoryl chloride, sulfuryl chloride, phosphorus trichloride, phosphorus pentachloride, phosphorus tribromide, phosphorus pentabromide, hydrogen bromide, hydrogen iodide Etc.) can be reacted to derive the corresponding carboxylic acid halide.

Specific examples of the carboxylic acid halide having a nitrogen-containing perfluoroalkyl group represented by the above formula (4) (that is, specific examples of Rf ¹ , Rf ² and Rf ³ ) include, for example, the following formulas (39) to (39) The structure represented by (58) is mentioned.

  The alcohol represented by the above formula (5) is commercially available as an ethylene glycol ether, propylene glycol ether or the like (for example, Nippon Emulsifier Co., Ltd.) and can be easily obtained.

Also, specific examples of the alcohol represented by the formula (5) (i.e., specific examples of ^{R 1} and ^{R 2)} as, for example, include the structures represented by the following formula (59) - (73).

  Examples of the aprotic solvent used in the reaction of the carboxylic acid halide having a nitrogen-containing perfluoroalkyl group represented by the general formula (4) and the alcohol represented by the general formula (5) include acetonitrile, toluene, benzene, and diethyl. Examples of the solvent include ether, diisopropyl ether, tetrahydrofuran, chloroform, dichloromethane, dimethyl sulfoxide, dimethylformamide, and any mixture thereof, and acetonitrile, toluene, and tetrahydrofuran are particularly preferable.

  Bases include sodium fluoride, potassium fluoride, lithium fluoride, ammonium fluoride, sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium carbonate, potassium carbonate, lithium carbonate, ammonium carbonate, sodium bicarbonate, hydrogen carbonate Potassium, lithium hydrogen carbonate, ammonium hydrogen carbonate, triethylamine, tripropylamine, tributylamine, trihexylamine, diisopropylethylamine, diethylamine, dipropylamine, diisopropylamine, dibutylamine, dihexylamine, pyridine, 2,6-dimethylpyridine, Although ammonia etc. can be illustrated, especially potassium fluoride and sodium fluoride are preferable.

  The amount of the base used is preferably 1 to 3 mol and more preferably 1.1 to 1.5 mol with respect to 1 mol of the alcohol represented by the general formula (5). Here, it is not preferable that the amount of the base used is less than 1 mol because the reaction does not proceed sufficiently. On the other hand, if it exceeds 3 mol, a step of removing excess base is required, which is not preferable.

  The amount of the alcohol represented by the general formula (5) is 0.8 to 2.0 moles per 1 mole of the carboxylic acid halide having a nitrogen-containing perfluoroalkyl group represented by the general formula (4). It is preferable to carry out, and it is more preferable to set it as 1.0-1.3 mol. Here, if the amount of alcohol used is less than 0.8 mol, the amount of carboxylic acid halide having a nitrogen-containing perfluoroalkyl group becomes excessive, which is not practical. On the other hand, when the amount exceeds 2.0 mol, it is not preferable because removal of alcohol becomes difficult.

  The reaction temperature is preferably -20 to 100 ° C, more preferably 0 to 50 ° C. Here, it is not preferable that the reaction temperature is less than −20 ° C. because a sufficient reaction rate cannot be obtained. On the other hand, when it exceeds 100 ° C., it is difficult to suppress the reaction, which is not preferable.

  The reaction time is preferably 0.5 to 24 hours, and more preferably 1 to 6 hours. Here, it is not preferable that the reaction time is less than 0.5 hours because the reaction does not proceed sufficiently. On the other hand, if it exceeds 24 hours, the reaction system becomes complicated, which is not preferable.

<Fluorine resin dispersant>
Next, the fluororesin dispersant of this embodiment will be described.
The fluororesin dispersant of this embodiment is characterized by containing the above-described nonionic fluorine-containing surfactant as a main component.

  Moreover, the fluororesin dispersant of this embodiment may contain a medium (for example, a liquid medium such as an organic solvent and water) as another component. Specifically, the concentration of the nonionic fluorine-containing surfactant in the fluororesin dispersant may be, for example, 0.01 to 10% by mass, or 0.05 to 1% by mass. Is preferred.

  The organic solvent applicable to the fluororesin dispersant of the present embodiment is not particularly limited. Specifically, for example, alcohol solvents such as methanol, ethanol and isopropyl alcohol, ketones such as acetone and methyl ethyl ketone are used. Solvents, ester solvents such as ethyl acetate and butyl acetate, fluorine such as α, α, α-trifluorotoluene, 1,3-bistrifluoromethylbenzene, 1,4-bistrifluoromethylbenzene, perfluorooctane and perfluorohexane A system solvent or the like can be used.

  In addition, in the dispersion | distribution of the fluororesin mentioned later, when using the fluororesin dispersant of this embodiment, the addition amount of the nonionic fluorine-containing surfactant in the fluororesin particles may be 0.01 to 10% by weight. Preferably, it is 0.5 to 5 weight%.

  Furthermore, in addition to the nonionic fluorine-containing surfactant described above, other fluorine-based surfactants, hydrocarbon-based surfactants, silicon-based surfactants, etc. are added to the fluororesin dispersant of this embodiment. May be.

  By the way, in prior patent documents (for example, JP-T-2006-516673, etc.), as a conventional fluororesin dispersant, a perfluoroalkyl group-containing oligomer-type fluorosurfactant having 6 or more carbon atoms in the perfluoroalkyl chain. Agents are disclosed. Among these, the fluororesin dispersant having 8 or more carbon atoms in the perfluoroalkyl chain has been feared to accumulate in a living body. Further, with a conventional fluororesin dispersant having a perfluoroalkyl chain having less than 8 carbon atoms, it has been difficult to uniformly disperse fluororesin particles having a low surface energy and a large specific gravity in water having a low viscosity.

  On the other hand, since the fluororesin dispersant of this embodiment contains the nonionic fluorine-containing surfactant described above as a main component, the surface tension of the dispersion medium or the resin solution is greatly reduced, and the fluororesin surface is reduced. It is possible to improve the wettability with respect to (that is, improve dispersibility) and to prevent aggregation of the fluororesin (that is, improve dispersion stability). Therefore, fine particles of fluororesin including PTFE (polytetrafluoroethylene) can be uniformly dispersed in water.

  Furthermore, the fluororesin dispersant of the present embodiment can be uniformly dispersed in water in a state close to a particle size substantially equal to the original fluororesin fine particles.

<Dispersion method of fluororesin>
Next, a method of using the fluororesin dispersant of the present embodiment, that is, a method of dispersing fluororesin fine particles in a dispersion medium will be described below.

(Fluorine resin fine particles)
The fluororesin that can be used in the dispersion method using the fluororesin dispersant of the present embodiment is not particularly limited. Specifically, for example, PTFE (polytetrafluoroethylene), PCTFE (polychlorotrifluoroethylene), PVDF (polyvinylidene fluoride), PFA (tetrafluoroethylene / perfluoroalkoxyethylene copolymer), FEP (tetrafluoroethylene). Ethylene / hexafluoropropylene copolymer), ETFE (ethylene / tetrafluoroethylene copolymer), ECTFE (ethylene / chlorotrifluoroethylene copolymer) and the like.
Further, the particle size of the fluororesin is not particularly limited, but may be, for example, in the range of 0.01 to 1000 μm, and preferably in the range of 0.1 to 100 μm.

(Dispersion medium)
The dispersion medium for dispersing the fine particles of the fluororesin is not particularly limited, and examples thereof include water, methanol, ethanol, isopropyl alcohol, ethylene glycol, acetone, methyl ethyl ketone, ethyl acetate, butyl acetate, toluene, xylene and the like. Organic solvents, fluorine-based inert liquids and the like can be mentioned.

(Fluorine resin dispersion method)
The method for dispersing the fluororesin is not particularly limited, and conventionally known methods can be applied. Specifically, usually by adding a required amount of the fluororesin dispersant of the present embodiment to a mixed liquid in which fine particles of the fluororesin are added to water or an organic solvent as a dispersion medium, stirring for a required time, A dispersion of fluororesin fine particles can be obtained.

  As explained above, since the nonionic fluorine-containing surfactant of the present embodiment is a perfluoroalkyl group-containing compound having a hetero atom, it has excellent surface tension reducing ability and has 6 carbon atoms. Since it does not have the above linear perfluoroalkyl group, it is a novel nonionic fluorine-containing surfactant having low bioaccumulation and excellent environmental adaptability.

  In addition, since the method for producing the nonionic fluorine-containing surfactant of the present embodiment is relatively easy to obtain a compound as a raw material and does not undergo a complicated reaction, the nonionic fluorine-containing surfactant is not included. It can be synthesized with good yield by a simple method.

  Furthermore, the nonionic fluorine-containing surfactant of the present embodiment can be suitably used for the use of a fluororesin dispersant. That is, the fluororesin dispersant mainly composed of the nonionic fluorine-containing surfactant of the present embodiment can uniformly disperse fluororesin fine particles in water with low viscosity, and has 6 or more carbon atoms. It is a novel fluororesin dispersant having low bioaccumulation and excellent environmental adaptability because it has no linear perfluoroalkyl group.

  The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

  Hereinafter, the effects of the present invention will be described in more detail by way of examples. In addition, this invention is not limited at all by the Example.

Example 1
In a three-necked flask equipped with a dropping funnel, alcohol (92.8 g) (trade name: MPG-130-H2, molecular weight: 428, manufactured by Nippon Emulsifier Co., Ltd.) and potassium fluoride (13.9 g) (Wako Pure Chemical Industries, Ltd.) And acetonitrile (220 ml) were added. In the dropping funnel, “CF ₂ (CF ₂ CF ₂ ) ₂ NCF ₂ CF (CF ₃ ) obtained by electrolytic fluorination of“ CH ₂ (CH ₂ CH ₂ ) ₂ NCH ₂ CH (CH ₃ ) CO ₂ CH ₃ ”. ) COF "(100.0 g) was added and gradually added dropwise at room temperature.
After completion of the dropwise addition, the mixture was stirred at room temperature for 1 hour, and the precipitated KF / HF was removed by filtration. The obtained solution was concentrated by a rotary evaporator, redissolved in toluene (150 ml), and the precipitated solid was removed by filtration. Further, the resulting solution was reconcentrated and redissolved in acetonitrile (150 ml).
The obtained solution was filtered and concentrated to obtain 169.9 g (yield 90%) of a nonionic fluorine-containing surfactant represented by the following general formula (74).

(Example 2)
Instead of the alcohol (trade name: MPG-130H2, average molecular weight: 428, manufactured by Nippon Emulsifier Co., Ltd.) used in Example 1 above, alcohol (trade name: MPG-081, average molecular weight: 692, manufactured by Nippon Emulsifier Co., Ltd.) is used. The nonionic fluorine-containing surfactant (yield 90%) represented by the following general formula (75) was obtained in the same manner as in Example 1 except that.

(Example 3)
Instead of “CF ₂ (CF ₂ CF ₂ ) ₂ NCF ₂ CF (CF ₃ ) COF” used in Example 1 above, “O (CH ₂ CH ₂ ) ₂ NCH ₂ CH (CH ₃ ) CO ₂ CH ₃ ”is represented by the following general formula (76) in the same manner as in Example 1 except that“ O (CF ₂ CF ₂ ) ₂ NCF ₂ CF (CF ₃ ) COF ”obtained by electrolytic fluorination is used. A nonionic fluorine-containing surfactant (yield 86%) was obtained.

Example 4
Instead of “CF ₂ (CF ₂ CF ₂ ) ₂ NCF ₂ CF (CF ₃ ) COF” used in Example 2 above, “O (CH ₂ CH ₂ ) ₂ NCH ₂ CH (CH ₃ ) CO ₂ CH ₃ ”is represented by the following general formula (77) in the same manner as in Example 2 except that“ O (CF ₂ CF ₂ ) ₂ NCF ₂ CF (CF ₃ ) COF ”obtained by electrolytic fluorination is used. A nonionic fluorine-containing surfactant (yield 95%) was obtained.

(Example 5)
Electrolysis of “(C ₄ H ₉ ) ₂ NCH ₂ CH ₂ CO ₂ CH ₃ ” instead of “CF ₂ (CF ₂ CF ₂ ) ₂ NCF ₂ CF (CF ₃ ) COF” used in Example 1 above A nonionic fluorine-containing surfactant represented by the following general formula (78) (Example 78) except that “(C ₄ F ₉ ) ₂ NCF ₂ CF ₂ COF” obtained by fluorination was used. Yield 89%).

(Example 6)
Electrolysis of “(C ₄ H ₉ ) ₂ NCH ₂ CH ₂ CO ₂ CH ₃ ” instead of “CF ₂ (CF ₂ CF ₂ ) ₂ NCF ₂ CF (CF ₃ ) COF” used in Example 2 above A nonionic fluorine-containing surfactant represented by the following general formula (79) in the same manner as in Example 2 except that “(C ₄ F ₉ ) ₂ NCF ₂ CF ₂ COF” obtained by fluorination was used. Yield 89%).

(Example 7)
Instead of “CF ₂ (CF ₂ CF ₂ ) ₂ NCF ₂ CF (CF ₃ ) COF” used in Example 1 above, “(CH ₃ ) ₂ NCH ₂ CH (CH ₃ ) CO ₂ CH ₃ ” Nonionic fluorine-containing surfactant represented by the following general formula (80) in the same manner as in Example 1 except that “(CF ₃ ) ₂ NCF ₂ CF (CF ₃ ) COF” obtained by electrolytic fluorination was used. An agent (90% yield) was obtained.

(Comparative Example 1)
In a three-necked flask (50 ml) equipped with a dropping funnel, 6.02 g (12 mmol) of a fluorinated ether compound represented by the following formula (81), 4.00 g of polyethylene glycol monomethyl ether (average molecular weight: 400) ( 10 mmol) and 10 g of tetrahydrofuran were added. On the other hand, a solution prepared by dissolving 1.34 g (12 mmol) of potassium t-butoxide in 10 g of tetrahydrofuran was put into a dropping funnel, and the solution was gradually added dropwise to the above flask contents with stirring over about 30 minutes. . After completion of the dropping, stirring was further continued for 3 hours at room temperature (20 to 25 ° C.).
The reaction mixture was then transferred to a 100 ml round bottom flask, the solvent was evaporated using a rotary evaporator, and then subjected to an extraction treatment using 30 ml of ethyl acetate and 30 ml of water once. Subsequently, the organic layer was treated with 30 ml of saturated brine, and the extract was subjected to solvent evaporation using a rotary evaporator to obtain a crude product. The crude product was subjected to column chromatography purification using 50 g of alumina to obtain 6.28 g of a compound represented by the following general formula (82) (yield: 73%).

(Comparative Example 2)
In a three-necked flask (50 ml) equipped with a dropping funnel, 6.02 g (12 mmol) of the fluorine-containing ether compound represented by the above formula (81), 10.00 g of polyethylene glycol monomethyl ether (average molecular weight: 1000) ( 10 mmol) and 10 g of tetrahydrofuran were added. On the other hand, a solution prepared by dissolving 1.34 g (12 mmol) of potassium t-butoxide in 10 g of tetrahydrofuran was put into a dropping funnel, and the solution was gradually added dropwise to the above flask contents with stirring over about 30 minutes. After completion of the dropping, stirring was further continued for 3 hours at room temperature (20 to 25 ° C.).
The reaction mixture was then transferred into a 100 ml round bottom flask and the solvent was evaporated using a rotary evaporator. After adding 10 g of acetonitrile and allowing to stand for 1 day, a precipitate was collected by filtration and the solvent was evaporated twice to obtain a crude product. The crude product was treated with an ion exchange resin to obtain 2.76 g of a compound represented by the following general formula (83) (yield: 37%).

(Comparative Example 3)
Nonionic fluorine-containing surfactant having a perfluoroalkyl group having 8 carbon atoms represented by the following general formula (84) described in technical literature “Oil Chemistry 1997, Vol. 26, pages 613-619” ( PFOS derivative) was prepared.

(Verification test 1)
"Evaluation of surface active ability of nonionic fluorine-containing surfactant"
In order to evaluate the surface activity of the nonionic fluorine-containing surfactant synthesized in Examples 1 to 7 and Comparative Examples 1 to 3, surface tension in an aqueous solution was measured. The surface tension was measured by the Wilhelmy method using an automatic surface tension meter CBVP-Z type manufactured by Kyowa Interface Science Co., Ltd. The evaluation results are shown in Table 1 below.

  As shown in Table 1, the nonionic fluorine-containing surfactants of Examples 1 to 7 are equivalent in the same addition amount as compared with Comparative Example 1 and Comparative Example 2 which are conventional nonionic fluorine-containing surfactants. It was found to have the above surface activity. Moreover, it turned out that it has equivalent surface-active ability compared with the comparative example 3 which is a PFOS derivative | guide_body in which the accumulation | storage property to an environment and a biological body is a problem. On the other hand, the nonionic fluorine-containing surfactants of Examples 1 to 7 have a high yield of 85% or more as compared with Comparative Example 1 and Comparative Example 2, which are conventional nonionic fluorine-containing surfactants. I found out.

(Verification test 2)
"Evaluation of wettability of nonionic fluorine-containing surfactant"
In order to evaluate the wettability of the nonionic fluorine-containing surfactant, an aqueous solution in which the above surfactant was dissolved at a concentration of 1000 ppm was used, and the wettability on the PET film and the PTFE sheet was compared. The evaluation results are shown in Table 2 below.
The evaluation criteria are as follows.
Droplet volume: 50 μl
○: Droplet spreads and droplet shape is not maintained △: Droplet does not spread and droplet shape remains

  As shown in Table 2, it was found that the nonionic fluorine-containing surfactant of the present invention was excellent in wettability with respect to a PET film and a PTFE sheet.

(Example 8)
2 g of PTFE powder (particle size: 1 μm) is added to 50 g of water, and 0.05 g of the nonionic surfactant synthesized in Example 1 is used as a fluororesin dispersant. Then, 10 g of ceramic beads are added, and the mixture is shaken for 2 hours using a paint shaker. Dispersed. When the dispersed liquid was measured with a particle size distribution meter (manufactured by Shimadzu Corporation, laser diffraction particle size distribution measuring device, SALD-200V, the same applies hereinafter), the average particle size was 2 μm (see Table 3 below). .

Example 9
2 g of PTFE powder (particle size: 1 μm) is added to 50 g of water, and 0.05 g of the nonionic surfactant synthesized in Example 2 is used as a fluororesin dispersant. Then, 10 g of ceramic beads are added, and the mixture is shaken for 2 hours using a paint shaker. Dispersed. When the dispersed liquid was measured with a particle size distribution meter, the average particle size was 2 μm (see Table 3 below).

(Comparative Example 4)
2 g of PTFE powder (particle size: 1 μm) is added to 50 g of water, and 0.05 g of a nonionic surfactant having a linear perfluoroalkyl group having 6 or less carbon atoms synthesized in Comparative Example 1 is used as a fluororesin dispersant. After that, 10 g of ceramic beads were added and dispersed with a paint shaker for 2 hours. When the dispersed liquid was measured with a particle size distribution meter, the average particle size was 31 μm (see Table 3 below).

(Comparative Example 5)
2 g of PTFE powder (particle size: 1 μm) is added to 50 g of water, and 0.05 g of a nonionic surfactant having a linear perfluoroalkyl group having 6 or less carbon atoms synthesized in Comparative Example 2 is used as a fluororesin dispersant. After that, 10 g of ceramic beads were added and dispersed with a paint shaker for 2 hours. When the dispersed liquid was measured with a particle size distribution meter, the average particle size was 51 μm (see Table 3 below).

(Comparative Example 6)
2 g of PTFE powder (particle size: 1 μm) in 50 g of water and 0.05 g of the nonionic surfactant (PFOS derivative) shown in Comparative Example 3 as a fluororesin dispersant were added, and 10 g of ceramic beads were added. For 2 hours. When the dispersed liquid was measured with a particle size distribution meter, the average particle size was 17 μm (see Table 3 below).

(Verification test 3)
As shown in Table 3, by using the nonionic fluorine-containing surfactant of the present invention as a fluororesin dispersant, fluororesin fine particles such as PTFE are close to the original particle size (particle size before dispersion). Thus, it was confirmed that it could be uniformly dispersed in water.

  The nonionic fluorine-containing surfactant of the present invention is excellent in surface tension reducing ability, low in bioaccumulation, and excellent in environmental adaptability. Therefore, a leveling agent and a dispersant (particularly a fluororesin dispersant), It is useful in a wide range of applications such as emulsifiers and antifoaming agents.

Claims (16)

Nonionic fluorine-containing surfactant represented by the following general formula (1).

In the above formula (1), Rf ¹ and Rf ² are the same or different C 1-6 perfluoroalkyl groups, and may be linear or branched. Rf ¹ and Rf ² may be directly bonded to form a ring, or may be bonded through an oxygen atom or a nitrogen atom to form a heterocyclic ring. Further, Rf ³ is a C 1-6 perfluoroalkylene group, and may be linear or branched.
Moreover, in said formula (1), R < ¹ > is a hydrogen atom or a methyl group. R ² is a linear or branched alkyl group having 1 to 8 carbon atoms. Furthermore, n is an integer of 3-50. 2. The nonionic fluorine-containing surfactant according to claim 1, wherein in the formula (1), R ¹ is a hydrogen atom. The formula (1), nonionic fluorinated surfactant according to claim 1 or 2, characterized in that R ² is a methyl group. The nonionic fluorine-containing surfactant according to claim 1, which has a perfluoroheterocycle containing a nitrogen atom represented by the following general formula (2).

In the above formula (2), Rf ⁴ , Rf ⁵ and Rf ⁶ are the same or different perfluoroalkylene groups having 1 to 6 carbon atoms, and may be linear or branched. X is an oxygen atom, a nitrogen atom or a CF ₂ group.
In the above formula (2), R ³ is a hydrogen atom or a methyl group. R ⁴ is a linear or branched alkyl group having 1 to 8 carbon atoms. Furthermore, n is an integer of 3-50. The nonionic fluorine-containing surfactant according to claim 4, wherein R ³ in the formula (2) is a hydrogen atom. The nonionic fluorine-containing surfactant according to claim 4 or 5, wherein R ⁴ in the formula (2) is a methyl group. The nonionic fluorine-containing surfactant according to claim 1, which has a linear perfluoroalkyl group represented by the following general formula (3).

In the above formula (3), m and n are the same or different integers of 1 to 6, respectively. Rf ⁷ is a perfluoroalkylene group having 1 to 6 carbon atoms, and may be linear or branched.
In the above formula (3), R ⁵ is a hydrogen atom or a methyl group. R ⁶ is a linear or branched alkyl group having 1 to 8 carbon atoms. Furthermore, n is an integer of 3-50. The formula (3), a nonionic fluorinated surfactant according to claim 7, wherein R ⁵ is a hydrogen atom. The nonionic fluorine-containing surfactant according to claim 7 or 8, wherein in the formula (3), R ⁶ is a methyl group. It is a manufacturing method of the nonionic fluorine-containing surfactant according to claim 1,
Nonionic fluorine-containing surfactant, characterized by using a carboxylic acid halide having a nitrogen-containing perfluoroalkyl group represented by the following general formula (4) and an alcohol represented by the following general formula (5) as raw materials Manufacturing method.

In the above formula (4), Rf ¹ and Rf ² are the same or different C 1-6 perfluoroalkyl groups, and may be linear or branched. Rf ¹ and Rf ² may be directly bonded to form a ring, or may be bonded through an oxygen atom or a nitrogen atom to form a heterocyclic ring. Rf ³ is a C 1-6 perfluoroalkylene group, and may be linear or branched. Further, Y is any one halogen atom selected from the group consisting of fluorine, chlorine, bromine and iodine.

In said formula (5), R < ¹ > is a hydrogen atom or a methyl group. R ² is a linear or branched alkyl group having 1 to 8 carbon atoms. Furthermore, n is an integer of 3-50.   A carboxylic acid halide having a nitrogen-containing perfluoroalkyl group represented by the general formula (4) and an alcohol represented by the general formula (5) are reacted in an aprotic solvent in the presence of a base. The method for producing a nonionic fluorine-containing surfactant according to claim 10.   The aprotic solvent is a solvent selected from the group consisting of acetonitrile, toluene, benzene, diethyl ether, diisopropyl ether, tetrahydrofuran, chloroform, dichloromethane, dimethyl sulfoxide, dimethylformamide, and any mixture thereof. The manufacturing method of the nonionic fluorine-containing surfactant of Claim 11. The base is a base selected from the group consisting of any one of compounds selected from the group consisting of MF, MOH, M ₂ CO ₃ , MHCO ₃ , amine, ammonia, or any mixture thereof; The manufacturing method of the nonionic fluorine-containing surfactant of Claim 11 or 12 characterized by the above-mentioned. However, said M is any one of Na, K, Li, and an ammonium cation. In the above formula (5), the manufacturing method of the nonionic fluorinated surfactant according to any one of claims 10 to 13 R ¹ is characterized in that it is a hydrogen atom. In the above formula (5), the manufacturing method of the nonionic fluorinated surfactant according to any one of claims 10 to 14 R ² is characterized in that it is a methyl group.   A fluororesin dispersant comprising the nonionic fluorine-containing surfactant according to claim 1.