Emulsion and method for producing same

Abstract

To provide an emulsion of perfluoropolyether phosphate ester.SOLUTION: An emulsion comprises (A) a perfluoropolyether phosphate ester compound represented by a formula (I), (B) a fluorine-based anionic surfactant with a counter cation, (C) chitin nanofibers, and (D) water [where Rf is a C1-4 perfluoroalkyl group. X is a fluoro group or a trifluoromethyl group. Y is a C1-10 divalent group. m is 5-60. n is 1 or 2].SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an emulsion and a method for producing the same. [Background technology]

[0002] High-molecular-weight perfluoropolyether compounds (e.g., those with a weight-average molecular weight of 2000 or more) generally dissolve in fluorine-based solvents, but have very low solubility in water and other organic solvents. Therefore, when preparing compositions containing perfluoropolyether compounds, fluorine-based solvents are usually used. However, fluorine-based solvents are expensive and have an environmental impact, so aqueous compositions have been desired.

[0003] Techniques for preparing emulsions containing perfluoropolyether oils are known, such as those disclosed in Patent Documents 1 and 2, but both require an ultrasonic homogenizer or a high-pressure homogenizer, and are therefore hardly simple methods. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 1995 / 18194 [Patent Document 2] Japanese Patent Application Publication No. 2020-158600 Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present invention is to provide an emulsion of a perfluoropolyether phosphate ester. [Means for solving the problem]

[0006] In order to solve the above problems, the present inventors conducted extensive research and found that an emulsion of perfluoropolyether phosphate ester can be prepared by using perfluoropolyether phosphate ester, a fluorine-based anionic surfactant having a counter cation, chitin nanofibers, and water.

[0007] The present invention has been completed based on these findings and includes the following broad aspects. [Section 1] (A) a perfluoropolyether phosphate ester compound represented by the following formula (I), (B) a fluorine-containing anionic surfactant having a counter cation; (C) Chitin nanofibers, (D)Water An emulsion comprising [ka] [In the formula, Rf is a perfluoroalkyl group having 1 to 4 carbon atoms, X is a fluoro group or a trifluoromethyl group, Y is a divalent group having 1 to 10 carbon atoms, m is 5 to 60, and n is 1 or 2.] [Section 2] Item 2. The emulsion according to Item 1, wherein the perfluoropolyether phosphate ester compound (A) has a weight average molecular weight in the range of 2,000 to 20,000. [Section 3] Item 3. The emulsion according to item 1 or 2, wherein the content of the fluorine-based anionic surfactant (B) is 10 to 40 parts by mass per 100 parts by mass of the perfluoropolyether phosphate ester compound (A). [Section 4] Item 4. The emulsion according to any one of Items 1 to 3, wherein the content of the chitin nanofibers (C) is 0.3 to 10 parts by mass per 100 parts by mass of the perfluoropolyether phosphate ester compound (A). [Section 5] Item 5. A water- and oil-repellent agent comprising the emulsion according to any one of items 1 to 4. [Section 6] Item 5. A fiber treatment agent comprising the emulsion according to any one of items 1 to 4. [Section 7] Item 5. A release agent comprising the emulsion according to any one of items 1 to 4. [Section 8] A step of preparing a dispersion containing the perfluoropolyether phosphate ester compound (A), the fluorine-based anionic surfactant (B), and the chitin nanofibers (C); and a step of mixing the dispersion with the water (D) Item 5. A method for producing the emulsion according to any one of items 1 to 4, comprising: [Section 9] Item 9. The method according to Item 8, wherein the amount of water (D) mixed is 100 to 10,000 parts by mass per 100 parts by mass of the dispersion. [Effects of the Invention]

[0008] According to the present invention, an emulsion of a perfluoropolyether phosphate ester can be provided. DETAILED DESCRIPTION OF THE INVENTION

[0009] <Emulsion> The emulsion according to the present invention contains the following (A) to (D): (A) A perfluoropolyether phosphate ester compound represented by the following formula (I): [ka] [In the formula, Rf is a perfluoroalkyl group having 1 to 4 carbon atoms, X is a fluoro group or a trifluoromethyl group, Y is a divalent group having 1 to 10 carbon atoms, m is 5 to 60, and n is 1 or 2.] (B) A fluorine-containing anionic surfactant having a counter cation. (C) Chitin nanofibers. (D) Water.

[0010] Each component will be described in detail below.

[0011] (A) Perfluoropolyether phosphate ester compound represented by formula (I)

[0012] [ka]

[0013] Rf is a perfluoroalkyl group having 1 to 4 carbon atoms. Examples of the perfluoroalkyl group having 1 to 4 carbon atoms include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, and a perfluorobutyl group.

[0014] X is a fluoro group or a trifluoromethyl group, preferably a trifluoromethyl group.

[0015] The divalent group having 1 to 10 carbon atoms represented by Y may contain a heteroatom, and may be an aromatic group, a heteroaromatic group, a heterocyclic group, an aliphatic group, or an alicyclic group. Specific examples include the following groups.

[0016] -(CH2) N1 - (N1=1~10) -A-(CH2) N2 - (N2=1~5) -B-(CH2) N3 - (N3=1~5) -CH2CH2(OCH2CH2) N4 - (N4=1~4) -BCO(OCH2CH2) N5 - (N5=1~4) (In the formula, A represents -O-CO-, -CO-O-, -CONH-, or -NHCO-. B represents phenylene which may have 1 to 3 substituents selected from the group consisting of alkyl groups having 1 to 3 carbon atoms (methyl, ethyl, propyl), alkoxy groups having 1 to 4 carbon atoms (methoxy, ethoxy, propoxy, butoxy, etc.), and halogen atoms (F, Cl, Br, I).)

[0017] Preferred divalent groups having 1 to 10 carbon atoms represented by Y include divalent groups having the following structures:

[0018] -(CH2) N1 - (N1=1~10) -CONH-(CH2) N2 - (N2=1~5) -CO-O-(CH2) N2 - (N2=1~5)

[0019] m is 5 to 60, preferably 10 to 50, and more preferably 15 to 35. n is 1 or 2.

[0020] In the emulsion of the present invention, the perfluoropolyether phosphate ester compound (A) represented by the above formula (I) may be used alone or in combination of two or more. Also, as the perfluoropolyether phosphate ester compound (A), a compound in which n in formula (I) is 1 and a compound in which n is 2 may be mixed and used.

[0021] The perfluoropolyether phosphate ester compound (A) preferably has a weight-average molecular weight of 2,000 or more, more preferably 2,500 or more, and particularly preferably 3,000 or more. The weight-average molecular weight is preferably 20,000 or less, more preferably 15,000 or less, even more preferably 12,000 or less, even more preferably 10,000 or less, particularly preferably 8,000 or less, and most preferably 5,000 or less. The weight-average molecular weight can be measured by a conventional method such as gel filtration chromatography.

[0022] Furthermore, the perfluoropolyether phosphate ester compound (A) can form metal salts, amine salts, ammonium salts, etc. by reacting with a basic metal compound, an amine compound, ammonia, etc., and these salts also have the same utility as the perfluoropolyether phosphate ester compound (A). Examples of metal salts include alkali metal salts, alkaline earth metal salts, and transition metal salts. Specific examples of metal atoms that form metal salts include Li, Na, K, Ca, Mg, Cu, Co, Ni, Zn, Mn, Fe, Pb, Hg, and Zr. Examples of amine compounds or ammonia that form amine salts or ammonium salts include ammonia, trimethylamine, triethylamine, benzylamine, methylbenzylamine, dimethylbenzylamine, monoethanolamine, diethanolamine, triethanolamine, morpholine, and pyridine.

[0023] Specific examples of the perfluoropolyether phosphate ester compound (A) include, but are not limited to, the following:

[0024] [ka]

[0025] [In the formula, m is 5 to 60.]

[0026] [ka]

[0027] [In the formula, m is 5 to 60.]

[0028] [ka]

[0029] [In the formula, m is 5 to 60.]

[0030] [ka]

[0031] [In the formula, m is 5 to 60.]

[0032] [ka]

[0033] [In the formula, m is 5 to 60.]

[0034] [ka]

[0035] [In the formula, m is 5 to 60.]

[0036] The perfluoropolyether phosphate ester compound (A) can be commercially available or can be produced by a known method, for example, by phosphate esterification of the hydroxyl groups of a perfluoropolyether monool represented by the following formula (II):

[0037] [ka]

[0038] [In the formula, Rf is a perfluoroalkyl group having 1 to 4 carbon atoms, X is a fluoro group or a trifluoromethyl group, Y is a divalent group having 1 to 10 carbon atoms, and m is 5 to 60.]

[0039] In the above formula (II), Rf, X, Y, and m are the same as those in the above formula (I).

[0040] The perfluoropolyether monool represented by the above formula (II) preferably has a weight-average molecular weight of 1,000 or more, more preferably 1,500 or more, even more preferably 2,000 or more, particularly preferably 2,500 or more, and most preferably 3,000 or more. The weight-average molecular weight is preferably 20,000 or less, more preferably 15,000 or less, even more preferably 12,000 or less, even more preferably 10,000 or less, particularly preferably 8,000 or less, and most preferably 5,000 or less. The weight-average molecular weight can be measured by a conventional method such as gel filtration chromatography.

[0041] The perfluoropolyether monool represented by the formula (II) can be commercially available or can be produced by a known method. The perfluoropolyether monool represented by the formula (II) can be synthesized according to the method disclosed in, for example, U.S. Patent Publication No. 3,293,306.

[0042] The hydroxyl groups of the perfluoropolyether monool represented by formula (II) can be converted into phosphoric acid esters by known methods, such as by using diphosphorus pentoxide (PO).

[0043] From the viewpoint of emulsion stability, the content of the perfluoropolyether phosphate ester compound (A) in the emulsion of the present invention is preferably 0.2 to 40 mass%, more preferably 0.4 to 30 mass%, even more preferably 1 to 25 mass%, particularly preferably 2 to 20 mass%, and most preferably 5 to 15 mass%, relative to 100 mass% of the total amount of the emulsion.

[0044] (B) Fluorine-containing anionic surfactant with a counter cation The fluorine-based anionic surfactant (B) having a counter cation is preferably a fluorocarbon surfactant, such as a surfactant having a perfluoroalkyl group or a perfluoroalkenyl group. Examples of surfactant (B) include the following (i) to (iv). Among these, carboxylate (i) or sulfonate (ii) is preferred. These may be used alone or in combination of two or more.

[0045] (i) a carboxylic acid salt represented by the following formula: Rf1COOM1 (In the formula, Rf1 represents a fluoroorganic group, and M1 represents an alkali metal, an amine base, or an ammonium base.)

[0046] (ii) a sulfonate represented by the following formula: Rf2SO3M2 (In the formula, Rf2 represents a fluoroorganic group, and M2 represents an alkali metal, an amine base, or an ammonium base.)

[0047] (iii) a phosphonate represented by the following formula: Rf3PO(OM3)(OM4) (In the formula, Rf3 represents a fluoroorganic group. M3 represents a hydrogen atom, an alkali metal, an amine base, or an ammonium base. M4 represents an alkali metal, an amine base, or an ammonium base.)

[0048] (iv) Phosphate represented by the following formula: RF4OPO(OM5)(OM6) (In the formula, Rf4 represents a fluoroorganic group. M5 represents a hydrogen atom, an alkali metal, an amine base, or an ammonium base. M6 represents an alkali metal, an amine base, or an ammonium base.)

[0049] The fluoroorganic groups represented by Rf1 to Rf4 are preferably substituted or unsubstituted fluorohydrocarbon groups having 3 to 20 carbon atoms (preferably 5 to 20 carbon atoms, more preferably 10 to 20 carbon atoms).

[0050] Examples of the substituted or unsubstituted fluorohydrocarbon group having 3 to 20 carbon atoms include a substituted or unsubstituted fluoroalkyl group having 3 to 20 carbon atoms, a substituted or unsubstituted fluoroalkenyl group having 3 to 20 carbon atoms, a substituted or unsubstituted fluorocycloalkyl group having 3 to 20 carbon atoms, a substituted or unsubstituted fluoroaryl group having 6 to 20 carbon atoms, and a substituted or unsubstituted fluoroaralkyl group having 7 to 20 carbon atoms. Among these, a substituted or unsubstituted fluoroalkyl group having 3 to 20 carbon atoms or a substituted or unsubstituted fluoroalkenyl group having 3 to 20 carbon atoms is preferred, and a substituted or unsubstituted perfluoroalkyl group having 3 to 20 carbon atoms or a substituted or unsubstituted perfluoroalkenyl group having 3 to 20 carbon atoms is more preferred.

[0051] Examples of the substituent include a halogen atom, C1 to C4 alkoxy, aryloxy, aralkyloxy, C1 to C4 alkyl, C2 to C4 alkenyl, NO, NO2, NH2, CN, OH, SH, COOH, CONH2, NHCOCH3, monoalkylamino, dialkylamino, monoalkylaminocarbonyl, dialkylaminocarbonyl, alkoxycarbonyl, and aryloxycarbonyl.

[0052] In addition, in Rf1 to Rf4, the fluorohydrocarbon group may be substituted with at least one heteroatom such as an oxygen atom, a nitrogen atom, or a sulfur atom. The number of heteroatoms is preferably 1 to 10, and more preferably 1 to 6. When the fluorohydrocarbon group is substituted with at least one heteroatom such as an oxygen atom, a nitrogen atom, or a sulfur atom, the fluorohydrocarbon group has at least one group such as -O-, -N<, -S-, -SO2-, -(C=O)-, -(C=O)O-, -O(C=O)-, -NH(C=O)-, -(C=O)NH-, -NH(C=O)O-, or -O(C=O)NH-, and the fluorohydrocarbon chain is interrupted by this group. In Rf1 to Rf4, the fluorohydrocarbon group may be substituted with a heteroatom, so that Rf1 to Rf4 may have a heterocyclic structure.

[0053] When the fluoroorganic groups represented by Rf1 to Rf4 are substituted fluorohydrocarbon groups having 3 to 20 carbon atoms, they preferably have one or more ether bonds (—O—).

[0054] Examples of alkali metals in M1 to M6 include lithium, sodium, potassium, etc. Examples of amine bases include trimethylamine, triethylamine, benzylamine, methylbenzylamine, dimethylbenzylamine, monoethanolamine, diethanolamine, triethanolamine, morpholine, pyridine, etc. Note that counter cations consisting of alkali metals, amine bases, or ammonium bases may be introduced (salt formation) by neutralizing an acid compound (free acid) in which all of M1 to M6 are hydrogen atoms.

[0055] Examples of the fluorine-based anionic surfactant (B) include Ftergent 100, Ftergent 110, Ftergent 150 (all manufactured by Neos Corporation), Surflon S-211 (manufactured by AGC Sei Chemical Co., Ltd.), Zonyl TBS (manufactured by DuPont), Megafac F-410, Megafac F-510 (all manufactured by DIC Corporation), PF-136A, PF-156A (all manufactured by OMNOVA), and the like.

[0056] From the viewpoint of emulsion stability, the content of the fluorine-containing anionic surfactant (B) in the emulsion of the present invention is preferably 0.04 to 15% by mass, more preferably 0.1 to 12% by mass, even more preferably 0.2 to 10% by mass, particularly preferably 0.5 to 8% by mass, and most preferably 1 to 5% by mass, relative to 100% by mass of the total amount of the emulsion.

[0057] From the viewpoint of emulsion stability, the content of the fluorine-based anionic surfactant (B) in the emulsion of the present invention is preferably 10 to 40 parts by mass, more preferably 12 to 35 parts by mass, particularly preferably 15 to 30 parts by mass, and most preferably 15 to 25 parts by mass, per 100 parts by mass of the perfluoropolyether phosphate ester compound (A).

[0058] (C) Chitin nanofiber Chitin is the main component of the cuticle that covers the body surfaces of many invertebrates, such as the exoskeletons of arthropods and crustaceans, and the surface of the shells of mollusks, as well as the cell walls of fungi such as mushrooms. Chitin is a linear, nitrogen-containing polysaccharide polymer (poly-β1-4-N-acetylglucosamine). Chitin nanofiber is a fibrous form obtained by unraveling chitin obtained from the above raw materials to the nano-size level.

[0059] The inclusion of chitin nanofibers (C) in the emulsion of the present invention can further improve the stability of the emulsion. Although the reason for this effect is unclear, it is presumed that the emulsion is stabilized by the interaction between the chitin nanofibers (C) and the perfluoropolyether phosphate ester compound (A).

[0060] The chitin nanofibers (C) preferably have an average fiber diameter of 2 to 100 nm, more preferably 5 to 70 nm, and particularly preferably 10 to 50 nm. The average fiber length is preferably 0.5 to 200 μm, more preferably 0.5 to 100 μm, and particularly preferably 0.5 to 50 μm. The average fiber diameter and average fiber length can be determined by averaging the fiber diameters and fiber lengths obtained from the observation of each fiber using an atomic force microscope (AFM) or a transmission electron microscope (TEM).

[0061] The average aspect ratio (average fiber length / average fiber diameter) of the chitin nanofibers (C) has no particular lower limit, but is preferably 10 or more, and more preferably 50 or more. There is also no particular upper limit, but it is preferably 5000 or less, more preferably 2000 or less, and particularly preferably 1000 or less.

[0062] The viscosity of a 2 wt% aqueous solution of chitin nanofibers (C) at 25°C is preferably in the range of 50 to 3,500 mPa·s, more preferably in the range of 50 to 1,000 mPa·s. Having a viscosity within the above range improves emulsion stability. Here, viscosity refers to the viscosity calculated from measurements taken with an E-type viscometer (Toki Sangyo E-type viscometer TVE-25 (rotation speed 10 rpm)).

[0063] The chitin nanofibers (C) used may be commercially available products, or products produced by known production methods. Commercially available chitin nanofibers (C) include, for example, BiNFi-s SFo-20002, BiNFi-s SFo-20005, and BiNFi-s SFo-20010 (all manufactured by Sugino Machine Ltd.). Chitin nanofibers can also be produced using production methods described in WO2010 / 073758, WO2015 / 111686, JP 2012-236983, JP 2016-153470, etc.

[0064] From the viewpoint of emulsion stability, the content of the chitin nanofibers (C) in the emulsion of the present invention is preferably 0.001 to 2 mass%, more preferably 0.005 to 1.5 mass%, even more preferably 0.01 to 1 mass%, particularly preferably 0.05 to 0.5 mass%, and most preferably 0.1 to 0.3 mass%, relative to the total amount of the emulsion (100 mass%).

[0065] Furthermore, from the viewpoint of emulsion stability, the content of the chitin nanofibers (C) in the emulsion of the present invention is preferably 0.3 to 10 parts by mass, more preferably 0.5 to 7 parts by mass, particularly preferably 0.7 to 5 parts by mass, and most preferably 1 to 3 parts by mass, per 100 parts by mass of the perfluoropolyether phosphate ester compound (A).

[0066] (D)Water From the viewpoint of emulsion stability, the content of water (E) in the emulsion of the present invention is preferably 50 to 99% by mass, more preferably 60 to 97% by mass, even more preferably 65 to 95% by mass, particularly preferably 70 to 92% by mass, and most preferably 75 to 90% by mass, relative to 100% by mass of the total amount of the emulsion.

[0067] (Other additives) The emulsion of the present invention may contain, as appropriate, organic solvents other than the alcohol (D), rust inhibitors, catalysts, antibacterial agents, flame retardants, surfactants, antifoaming agents, thickeners, viscosity modifiers, leveling agents, UV absorbers, preservatives, antifreeze agents, wetting agents, pH adjusters, stabilizers, antifungal agents, light stabilizers, weather stabilizers, neutralizing agents, matting agents, drying accelerators, foaming agents, anti-tack agents, and anti-degradants, as long as the additives do not impair the objectives of the present invention. These additives may be used alone or in combination of two or more. Each of these additives may be used in an amount of 0.01 to 10 parts by mass per 100 parts by mass of the total of the perfluoropolyether phosphate ester compound (A), the fluorine-based anionic surfactant (B), and the chitin nanofibers (C).

[0068] <Emulsion manufacturing method> The emulsion of the present invention can be produced by a method including the following (Step 1) and (Step 2). (Step 1) A step of preparing a dispersion containing a perfluoropolyether phosphate ester compound (A), a fluorine-based anionic surfactant (B), and chitin nanofibers (C). (Step 2) A step of mixing the dispersion liquid with water (D).

[0069] In (Step 1), the order of mixing in the dispersion is not particularly limited. The perfluoropolyether phosphate ester compound (A) may be mixed with the fluorine-based anionic surfactant (B) and chitin nanofibers (C), or other mixing orders may be used. The chitin nanofibers (C) may also be mixed as an aqueous solution. When preparing an aqueous chitin nanofiber solution, it is recommended to prepare it so that the viscosity measured with a TVE-25 E-type viscometer (manufactured by Toki Sangyo Co., Ltd., at 10 rpm) is in the range of 50 to 3500 mPa·s, preferably 50 to 1000 mPa·s. Furthermore, various additives may be added as needed. It is preferable to mix these components and thoroughly stir them to ensure that each component is uniformly dispersed.

[0070] The amount of the fluorine-based anionic surfactant (B) mixed in the dispersion liquid is preferably 10 to 40 parts by mass, more preferably 12 to 35 parts by mass, particularly preferably 15 to 30 parts by mass, and most preferably 15 to 25 parts by mass, per 100 parts by mass of the perfluoropolyether phosphate ester compound (A).

[0071] The amount of chitin nanofibers (C) mixed in the dispersion is preferably 0.3 to 10 parts by mass, more preferably 0.5 to 7 parts by mass, particularly preferably 0.7 to 5 parts by mass, and most preferably 1 to 3 parts by mass, per 100 parts by mass of the perfluoropolyether phosphate ester compound (A).

[0072] In (Step 2), the method of mixing the dispersion and water (D) is preferably to gradually add water (D) while stirring the dispersion obtained in Step 1. By gradually adding water (D) to the dispersion and mixing it, it becomes easier to uniformly disperse each component.

[0073] The amount of water (D) mixed in (Step 2) is preferably 100 to 10,000 parts by mass, more preferably 150 to 3,500 parts by mass, even more preferably 200 to 2,000 parts by mass, particularly preferably 250 to 1,500 parts by mass, and most preferably 300 to 900 parts by mass, relative to 100 parts by mass of the dispersion.

[0074] The emulsion thus obtained can be mixed with various additives, if necessary.

[0075] <Uses of emulsion> The coating film obtained from the emulsion of the present invention has excellent releasability, liquid repellency, and continuous releasability, and therefore the emulsion of the present invention can be suitably used as a release agent, a water and oil repellent, a fiber treatment agent, etc.

[0076] The molding material or resin material that can be released using the emulsion of the present invention is not particularly limited, and examples thereof include rubbers such as urethane rubber, H-NBR, NBR, silicone rubber, EPDM, CR, NR, fluororubber, SBR, BR, IIR, and IR; thermosetting resins such as urethane foam, epoxy resin, polyimide resin, polyamide resin, melamine resin, urea resin, polyurethane, silicone resin, alkyd resin, phenolic resin, unsaturated polyester resin, vinyl ester resin, and FRP (glass fiber reinforced plastic (GFRP), carbon fiber reinforced plastic (CFRP), aramid fiber reinforced plastic (AFRP)); PP (polypropylene), PE (polyethylene), PVC (polyvinyl chloride), PS (polystyrene), PA (polyamide), polyester, polycarbonate, ABS resin, poly(meth)acrylic acid, polyacetal, polyvinylidene fluoride, polyphenylene sulfide, polyetherimide, polyether ether ketone, Examples include thermoplastic resins such as FRTP (glass fiber reinforced thermoplastic resin (GFRTP), carbon fiber reinforced thermoplastic resin (CFRTP), and aramid fiber reinforced thermoplastic resin (AFRTP)). It is particularly useful as a mold release agent for molds for resins such as polyurethane and epoxy resins.

[0077] Furthermore, materials to which the emulsion of the present invention can be applied include, but are not limited to, metals such as aluminum, SUS, and iron, resins such as PP, PE, and epoxy, rubber, FRP (fiber reinforced plastic), gypsum substrates, wooden substrates, fibers, glass, composite materials, etc. The emulsion of the present invention can impart high water and oil repellency to these materials.

[0078] In one embodiment, the emulsion of the present invention can be used as a fiber treatment agent. Fibers treated with the emulsion of the present invention may be in any form, such as short fibers, linters, rovings, slivers, yarns, woven fabrics, knitted fabrics, and nonwoven fabrics. Examples of fiber materials include cellulose fibers such as cotton, flax, jute, hemp, ramie, regenerated cellulose, and rayon, and polyvinyl alcohol-based synthetic fibers.

[0079] The emulsion of the present invention can be used by applying it to the area to be treated with the emulsion and drying it. When applying, the emulsion may be diluted with water or the like as needed. The concentration after dilution is appropriately selected depending on the application method and viscosity, and is not particularly limited. For example, the emulsion can be prepared so that the solids concentration is 0.1 to 5% by mass. The application method is not particularly limited, and examples thereof include spray application, brush application, roll coater application, and dipping application. Drying methods include air drying or heating to evaporate the solvent to form a film. The dry thickness of a film containing the emulsion of the present invention is usually 0.01 to 15 μm, and preferably 0.1 to 5.0 μm. [Example]

[0080] The present invention will be further explained below with reference to examples, but the present invention is not limited thereto.

[0081] (Materials used) PFPE phosphate ester 1: Perfluoropolyether phosphate ester CF3CF2CF2O-[CF(CF3)CF2O] m -CF(CF3)CH2OPO(OH)2 (weight average molecular weight 4000, m is about 24) FEOH-4000: Perfluoropolyether monool (manufactured by Sanmei Co., Ltd.) CF3CF2CF2O-[CF(CF3)CF2O] m -CF(CF3)CH2OH (weight average molecular weight 4000) FT-100: Futergent 100 (fluorine-based anionic surfactant, sodium sulfonate, manufactured by Neos Co., Ltd.) FT-150: Futergent 150 (fluorine-based anionic surfactant, sodium sulfonate, manufactured by Neos Co., Ltd.) FT-212M: Futergent 212M (nonionic surfactant, manufactured by Neos Co., Ltd.) Chitin nanofiber: Chitin nanofiber (manufactured by Sugino Machine Co., Ltd., SFo-20002, average fiber diameter 10-50 nm, viscosity of 2% aqueous solution 350 mPa·s (measured with a Toki Sangyo E-type viscometer TVE-25 at 10 rpm))

[0082] Example 1 PFPE phosphate ester 1 (10.0 g), FT-150 (2.0 g), and 2% chitin nanofiber aqueous solution (10.0 g) were placed in a 200 ml beaker equipped with a stir bar. The mixture was stirred with a magnetic stirrer for 10 minutes to produce a dispersion. While stirring the dispersion, distilled water (78.0 g) was gradually added dropwise. An emulsion with a PFPE phosphate ester concentration of 10 wt% was produced. The appearance of the resulting emulsion after emulsification was checked. The emulsion was diluted with distilled water to a concentration of 1 wt% of the active ingredient to prepare a coating sample. SPCC-SB was used as the coating substrate. After degreasing the coating substrate with acetone, it was heated to 170°C and a coating sample of 50 g / m was applied using a spray gun. 2After application, the sample was heated at 170°C for 1 minute to prepare an evaluation sample. The obtained evaluation sample was subjected to contact angle, surface free energy, and tape peeling tests. The results are shown in Tables 1 and 3.

[0083] (Evaluation of emulsion appearance) The emulsified liquid was visually inspected. 〇: Beautifully emulsified and stable. △: Emulsifies, but is unstable and gradually settles. ×: Unable to emulsify and separated into layers.

[0084] (Contact angle measurement) The contact angles of the evaluation sample with water, diiodomethane (DI), and hexadecane (HD) were measured using DMo-702 (manufactured by Kyowa Interface Science Co., Ltd.).

[0085] (surface free energy) The contact angle was calculated using the Kaelble-Uy formula from the values ​​measured above.

[0086] (Tape peel test) For the evaluation sample, Nitto Denko polyester adhesive tape No. 31B was applied to a 7.5cm 2 The load applied when the tape was peeled off at a 90° angle was measured using a push-pull gauge. The tape was also applied to the same location and the peeling test was repeated 10 times.

[0087] <Examples 2 to 3, Comparative Examples 1 to 4> Emulsions were prepared in the same manner as in Example 1, except that the compositions were changed as shown in Tables 1 and 2. Thereafter, the appearance, contact angle, surface free energy, and tape peeling test of the emulsified liquid were evaluated in the same manner as in Example 1. The results are shown in Tables 1 to 3.

[0088] [Table 1]

[0089] [Table 2]

[0090] [Table 3]

[0091] In Examples 1 to 3, a stable emulsion was obtained by stirring a perfluoropolyether phosphate ester in the presence of a fluorine-based anionic surfactant having a counter cation and chitin nanofibers, and then adding water dropwise after preparing a dispersion. Example 1 and Comparative Example 1 revealed that a stable emulsion could not be obtained when the perfluoropolyether phosphate ester was replaced with a perfluoropolyether monool. Example 1 and Comparative Example 2 revealed that a stable emulsion could not be obtained when a nonionic surfactant was used as the fluorine-based surfactant. Furthermore, no emulsion was obtained when a fluorine-based anionic surfactant having a counter cation was not added (Comparative Example 3). Furthermore, it was also revealed that no emulsion was obtained when chitin nanofibers were not included (Comparative Example 4).

[0092] In the coating evaluation, the surface free energy was shown to be sufficiently low, less than 16 mN / m, in both Examples 1 and 2. In the tape peeling test, the surface free energy remained less than 3 N even after 10 repetitions, confirming that the performance could be maintained even after repeated use.

Claims

1. (A) a perfluoropolyether phosphate ester compound represented by the following formula (I), (B) a fluorine-containing anionic surfactant having a counter cation; (C) chitin nanofibers; (D) Water An emulsion comprising 【Chemistry 1】 [In the formula, Rf is a perfluoroalkyl group having 1 to 4 carbon atoms, X is a fluoro group or a trifluoromethyl group, Y is a divalent group having 1 to 10 carbon atoms, m is 5 to 60, and n is 1 or 2.]

2. 2. The emulsion according to claim 1, wherein the weight average molecular weight of the perfluoropolyether phosphate ester compound (A) is in the range of 2,000 to 20,000.

3. 2. The emulsion according to claim 1, wherein the content of the fluorine-based anionic surfactant (B) is 10 to 40 parts by mass per 100 parts by mass of the perfluoropolyether phosphate ester compound (A).

4. 2. The emulsion according to claim 1, wherein the content of the chitin nanofibers (C) is 0.3 to 10 parts by mass per 100 parts by mass of the perfluoropolyether phosphate ester compound (A).

5. A water and oil repellent comprising the emulsion according to claim 1.

6. A textile treatment agent comprising the emulsion of claim 1.

7. A mold release agent comprising the emulsion of claim 1.

8. a step of preparing a dispersion containing the perfluoropolyether phosphate ester compound (A), the fluorine-based anionic surfactant (B), and the chitin nanofibers (C); and a step of mixing the dispersion with the water (D) A method for producing the emulsion of claim 1, comprising:

9. The method according to claim 8, wherein the amount of the water (D) mixed with respect to 100 parts by mass of the dispersion is 100 to 10,000 parts by mass.

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