JP2017133706A - Porous water absorption evaporation material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a porous water absorption evaporation material that can maintain water suction performance for a long time and suck water from a water-oil mixture where oil is contaminated in water even when being used under such an environment as a kitchen and a food factory where oil mist is generated.SOLUTION: The porous water absorption evaporation material includes a porous body having a continuous pore. In the porous water absorption evaporation material, a fluorine-based compound having an oil-repellency-imparting group and a hydrophilicity-imparting group is present on at least part of a surface of the continuous pore.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a porous water-absorbing and evaporating material for sucking up water using a capillary phenomenon and evaporating the sucked-up water.

  As a structure that sucks up water and evaporates the sucked-up water, a porous water-absorbing and evaporating material is known. The porous water-absorbing evaporating material is composed of a porous body having continuous pores, and sucks up water by utilizing the capillary phenomenon of the continuous pores. The porous water-absorbing evaporating material is used for applications such as evaporative removal of drain water in a refrigerator and generation of water vapor in a humidifier. The porous water-absorbing evaporating material is also used as a condensed water evaporation sheet for temporarily absorbing and evaporating the condensed water that has condensed on the window glass and has flowed down under the window frame.

In Patent Document 1, as a porous water-absorbing evaporating material for a drainage drainage device, water-absorbing fibers of 25 to 70% by weight, which are rayon fiber, polynosic fiber, cupra fiber, hemp, silk, wool, or a mixed cotton fiber thereof, It consists of a felt containing 25 to 45% by weight of a fusible fiber and 0 to 35% by weight of a heat-resistant fiber. The whole is integrated by carding and needle punching to melt all or part of the heat-fusible fiber. After heat treatment, it is formed into a thin sheet by hot pressing at 140 to 180 ° C., and the basis weight after hot pressing is 250 to 650 g / m ² , and when it stands vertically in water, it does not swell or buckle, and its vertical state An evaporating sheet that stably maintains the temperature is disclosed.

  Patent Document 2 discloses a non-woven sheet of polyester fiber surface-treated with a polyester-based hydrophilizing agent as a porous water-absorbing and evaporating material for a condensed water evaporation device. In Patent Document 2, as a polyester-based hydrophilic treatment agent, there is an aqueous dispersion of a copolymer having substantially the same structure as the molecular structure of a polyester-based fiber and further having a hydrophilic group such as a polyoxyethylene group or a sulfonic acid group. Have been described.

Furthermore, Patent Document 3 contains 30% by weight or more of fibers having a specific surface area of 0.4 m ² / g or more, a bulk density of 0.1 g / cm ³ or more, a basis weight of 30 g / m ² or more, a suction height of 200 mm or more, A fiber structure having water absorption and evaporating properties with a suction speed of 40 mm / 60 seconds or more and an evaporation speed of 90 g / m ² · hour or more is disclosed.

Japanese Patent No. 5232256 Japanese Patent No. 3446134 JP 2000-73265 A

It is desirable that the porous water-absorbing evaporating material can absorb water stably in various environments.
However, when the conventional porous water-absorbing evaporating material as described in Patent Documents 1 to 3 is used in an environment where oil mist is likely to occur, such as a kitchen or a food factory, the ability to suck up water decreases. There was a problem that there was something. In an environment where oil mist is generated, oil may be mixed into the drain water of the refrigerator or the water for steam generation of the humidifier. In some cases, water could hardly be sucked up.

  The present invention has been made in view of the above circumstances, and even when used in an environment where oil mist is generated such as in a kitchen or a food factory, the ability to suck up water can be maintained over a long period of time. It is an object of the present invention to provide a porous water-absorbing evaporating material capable of sucking water even from a mixed oil and water mixture.

  As a result of intensive studies by the inventors of the present application, as for a porous water-absorbing and evaporating material using a porous body having continuous pores, fluorine having an oil repellency imparting group and a hydrophilicity imparting group on at least a part of the surface of the continuous pores. The presence of water-based compounds makes it possible to absorb water even from a mixture of oil and water mixed with water, and even when used in an environment where oil mist is generated, the ability to absorb water for a long time The present invention has been completed.

That is, the porous water-absorbing and evaporating material of the present invention has the following configuration.
[1] A porous water-absorbing and evaporating material including a porous body having continuous pores, wherein a fluorine-based compound having an oil repellency-imparting group and a hydrophilicity-imparting group is present on at least a part of the surface of the continuous pores. It is characterized by that.

  [2] The fluorine compound is one or more nitrogen-containing fluorine compounds represented by any one of the following formulas (1) to (4).

In the above formulas (1) and (2), Rf ¹ and Rf ² are the same or different, each having 1 to 6 carbon atoms and a linear or branched perfluoroalkyl group, and Rf ³ is carbon It is number 1-6, Comprising: It is a linear or branched perfluoroalkylene group.
In the above formulas (3) and (4), Rf ⁴ , Rf ⁵ and Rf ⁶ are the same or different, each having 1 to 6 carbon atoms and a linear or branched perfluoroalkylene group, and Z is One of an oxygen atom, a nitrogen atom, a CF ₂ group and a CF group is included.
Moreover, in said formula (2) and (4), R is a coupling group which is a bivalent organic group.
Moreover, in said formula (1)-(4), X is any one hydrophilicity imparting group selected from the group which consists of an anionic type, a cationic type, and an amphoteric type.

  [3] The fluorine compound is bonded to the porous body by one or both of an organic binder and an inorganic binder.

  [4] The organic binder includes any one of a thermoplastic resin, a thermoplastic elastomer, a thermosetting resin, and a UV curable resin.

[5] The porous body is an aggregate of fibers, a foamed resin molded body, or a ceramic sintered body.
[6] The aggregate of fibers is an aggregate of organic fibers.
[7] The organic fiber is a synthetic fiber, natural fiber or cellulosic fiber.

  [8] The porous body is formed into a flat plate shape, a corrugated plate shape, a cylindrical shape, a columnar shape, or a honeycomb shape.

  According to the porous water-absorbing evaporating material of the present invention, even when used in an environment where oil mist is generated, such as in a kitchen or a food factory, the ability to suck up water can be maintained for a long period of time. Can be sucked up.

It is a schematic diagram which shows the usage example of the porous water absorption evaporating material in one Embodiment.

  Hereinafter, a porous water-absorbing and evaporating material as an embodiment to which the present invention is applied will be described with reference to the drawings. The following embodiments are specifically described for better understanding of the gist of the invention, and do not limit the present invention unless otherwise specified. In addition, in the drawings used in the following description, in order to make the features of the present invention easier to understand, there is a case where a main part is shown in an enlarged manner for convenience, and the dimensional ratio of each component is the same as the actual one. Not necessarily.

Drawing 1 is a mimetic diagram showing the example of use of the porous water absorption evaporation material in one embodiment.
In FIG. 1, the porous water-absorbing and evaporating material 1 has a flat plate shape, and a plurality of porous water-absorbing and evaporating materials 1 are supported and fixed by a fixture 2 in a state of being parallel and spaced apart. The fixture 2 is provided with recesses 3 at a predetermined interval, and the porous water-absorbing and evaporating material 1 is fitted into the recesses 3.

  The porous water-absorbing evaporating material 1 is composed of a porous body having continuous pores (not shown), and is configured so that when water is brought into contact with the lower portion, the water is sucked up by capillary action of the continuous pores and the water is evaporated. ing. In the porous water-absorbing and evaporating material 1 of the present embodiment, a fluorine-based compound having an oil repellency imparting group and a hydrophilicity imparting group is present on at least a part of the surface of the continuous pores. The presence of the fluorine-based compound having hydrophilicity and oil repellency (hereinafter sometimes referred to as a hydrophilic oil repellent) on the surface of the continuous pores increases the affinity between the inner walls of the continuous pores and water. Suction capacity is improved. In addition, the presence of the hydrophilic oil repellent on the surface of the continuous pores makes it difficult for the oil to enter the continuous pores, so that water can be sucked up even from a mixture of oil and water, and oil mist is generated. Even when used in the environment, the ability to absorb water is maintained over a long period of time. The hydrophilic oil repellent agent is preferably present on the entire surface of the continuous pores.

<Porous body>
The porous body which is the base material of the porous water-absorbing evaporating material 1 has continuous pores that can suck up water by capillary action. The opening diameter of the continuous pores is preferably in the range of 0.1 μm to 180 μm. When the opening diameter of the continuous pores of the porous body is within the above range, the oil is less likely to enter the continuous pores, so that the ability to suck water from the mixed liquid of oil and water is enhanced. The porous body is preferably a fiber aggregate, a foamed resin molded body (sponge), or a ceramic sintered body. The fiber aggregate and the foamed resin molded body have high elasticity compared to the ceramic sintered body, and are thus easily processed into an arbitrary shape. Ceramic sintered bodies have higher heat resistance than fiber aggregates and foamed resin molded bodies, so that the evaporation rate of water can be increased by heating.

  As the fiber assembly, a nonwoven fabric, a woven fabric, a knitted fabric, or a laminate sheet thereof can be used. The fiber aggregate may adhere or fuse the fibers to each other within a range that does not block the continuous pores (water flow paths). The fibers constituting the fiber assembly may be organic fibers or inorganic fibers. Examples of organic fibers include synthetic fibers, natural fibers, and cellulosic fibers. Specific examples of the synthetic fiber include polyester, polyamide, polyimide, polyacrylonitrile, polyolefin (polyethylene, polypropylene, etc.), and polyvinyl alcohol. Specific examples of natural fibers include cotton, hemp, and pulp. Specific examples of cellulosic fibers include rayon and acetate. Examples of inorganic fibers include metal fibers, carbon fibers, glass fibers, and ceramic fibers. These fibers may be used alone or in combination of two or more.

Examples of the material of the foamed resin molded body (sponge) include polyurethane, polystyrene, polyethylene, polypropylene, and polyvinyl alcohol.
Examples of ceramic sintered bodies include sintered bodies of oxides such as silica, alumina, magnesia, and zir core, and sintered bodies of nitrides such as silicon nitride and aluminum nitride.

  There is no restriction | limiting in particular about the shape of a porous material. The porous material can have any shape such as a flat plate shape, a corrugated plate shape (pleated shape), a tubular shape, a columnar shape, or a honeycomb shape. The porous material may have irregularities on the surface. By having irregularities on the surface, the contact area with the outside air is increased, and the evaporation rate of water is increased.

<Hydrophilic oil repellent>
As the hydrophilic oil repellent that is present in the continuous pores of the porous water-absorbing evaporating material 1, one or more nitrogen-containing fluorine-based compounds represented by any one of the following formulas (1) to (4) are used. It is preferable to use it. The following nitrogen-containing fluorine-based compound has a structure in which a hydrophilicity-imparting group is added to a nitrogen-containing perfluoro compound, and thus has high hydrophilicity and oil repellency.

In the above formulas (1) and (2), Rf ¹ and Rf ² are the same or different from each other, each having 1 to 6 carbon atoms and a linear or branched perfluoroalkyl group. Rf ³ is a linear or branched perfluoroalkylene group having 1 to 6 carbon atoms. Rf ¹ and Rf ² are each preferably the same or different from each other and each having 1 to 4 carbon atoms and is a linear or branched perfluoroalkyl group. Rf ³ has 1 to 4 carbon atoms, and is preferably a linear or branched perfluoroalkylene group.

In the above formulas (3) and (4), Rf ⁴ , Rf ^5, and Rf ⁶ are the same or different from each other, each having 1 to 6 carbon atoms and a linear or branched perfluoroalkylene group. Z includes an oxygen atom, a nitrogen atom, a CF ₂ group, or a CF group. When Z contains a nitrogen atom or a CF group, a perfluoroalkyl group branched from Z may be bonded to Z. Rf ⁴ , Rf ⁵ and Rf ⁶ are each preferably the same or different from each other and each having 1 to 4 carbon atoms and a linear or branched perfluoroalkylene group.

  Moreover, in said formula (2) and (4), R is a coupling group which is a bivalent organic group. Here, R may be a linear or branched organic group.

  Moreover, in said formula (1)-(4), X is any one hydrophilicity imparting group selected from the group which consists of an anionic type, a cationic type, and an amphoteric type.

[Linear or branched nitrogen-containing fluorine-based compound]
In the linear or branched nitrogen-containing fluorine-based compound represented by the above formula (1) or (2), a nitrogen-containing perfluoroalkyl group composed of Rf ¹ and Rf ² and a nitrogen-containing perfluoroalkylene group composed of Rf ³ Constitutes an oil repellency-imparting group.
Further, in the above formula (1) or the formula nitrogen-containing fluorine compound shown in (2), in Rf ¹ ~Rf ³ is the oil repellent imparts group, the total carbon number of fluorine is bonded is 4 to 18 pieces It is preferable that it is the range of these. If the number of carbons to which fluorine is bonded is less than 4, it is not preferable because the oil repellent effect is insufficient.

Here, in the above formula (2), R is a linking group that connects the oil repellency-imparting group and the hydrophilicity-imparting group in the molecular chain. The structure of the linking group R is not particularly limited as long as it is a divalent organic group. Specific examples of the linking group R include, for example, an oxygen atom [—O—], a carbonyl group [—C (═O) —], an imino group [—NH—], and a sulfonyl group [—S (═O). _2— ], —OP (═O) (O ⁻ ) O— group, hydrocarbon group having 1 to 20 carbon atoms, and combinations thereof. The linking group R may contain one or more selected from a polyoxyalkylene group and an epoxy group. The hydrocarbon group may be a saturated hydrocarbon group or an unsaturated hydrocarbon group. The hydrocarbon group may be a chain hydrocarbon group or a cyclic hydrocarbon group. The chain hydrocarbon group may be linear or branched. Examples of the hydrocarbon group include an alkylene group, an alkenylene group, and an arylene group. The imino group and the hydrocarbon group may have a substituent.

  The linking group R may or may not contain one or more types of bonds selected from ether bonds, ester bonds, amide bonds and urethane bonds in the molecular chain. The amide bond includes a carboxylic acid amide bond and a sulfonamide bond. The ester bond includes a carboxylic acid ester bond, a sulfonic acid ester bond, and a phosphate ester bond.

  In addition, it is preferable to select and introduce the linking group R as appropriate depending on the characteristics to be imparted to the nitrogen-containing fluorine-based compound. Specifically, for example, when it is desired to adjust the solubility in a solvent such as water or an organic solvent, or when it is desired to improve the durability by improving the adhesion to the base material (porous body). The method includes adjusting the chain length of a linear or branched hydrocarbon group that adjusts the presence or type of polar groups that affect the intermolecular interaction, and the chemical structure included in the substrate. Introducing a structure similar to the part.

Moreover, in said formula (1) or said formula (2), X is any one hydrophilicity imparting group selected from the group which consists of an anionic type, a cationic type, and an amphoteric type.
Hereinafter, the structure of the hydrophilic lube repellant will be described by dividing the hydrophilic imparting group X into cases.

(Anion type)
When the hydrophilic imparting group X is an anionic type, the above-mentioned X is “—CO ₂ M ¹ ”, “—SO ₃ M ¹ ”, “—OSO ₂ M ¹ ”, “—OP (OH) O _{2 at the terminal.} “M ¹ ”, “—OPO ₃ M ¹ ₂ ”, “═O ₂ PO ₂ M ¹ ” or “—PO (OH) _y (OM ¹ ) _{2 -y} ” (M ¹ is an alkali metal or alkaline earth metal) , Mg, Al, R ¹ R ² R ³ R ⁴ N ⁺ ; R ^{1 to} R ⁴ are each a hydrogen atom or an independent straight chain or branched chain having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms. Alkyl group). When M ¹ is a divalent metal (alkaline earth metal, Mg), two identical anions may be bonded to M ¹ or two different anions are bonded. Also good. When M1 is aluminum, three identical anions may be bonded to M1, or two or three different anions may be bonded.

  Examples of the alkali metal include lithium (Li), sodium (Na), potassium (K), and cesium (Cs). Examples of the alkaline earth metal include calcium (Ca), strontium (Sr), and barium (Ba).

As the quaternary ammonium salt ^{(R 1 R 2 R 3 R} 4 N +), up R 1 to R ⁴ is from 1 to 20 carbon atoms which independently hydrogen atom or each, preferably up to 10 carbon atoms There is no particular limitation as long as it is a linear or branched alkyl group. Here, it is preferable that the alkyl group has 20 or less carbon atoms because the hydrophilic oil repellency is not impaired. More specifically, examples of the compound in which R ¹ R ² R ³ R ⁴ are all the same include (CH ₃ ) ₄ N ⁺ , (C ₂ H ₅ ) ₄ N ⁺ , and (C ₃ H ₇ ) ₄ N ^+. , (C ₄ H ₉ ) ₄ N ⁺ , (C ₅ H ₁₁ ) ₄ N ⁺ , (C ₆ H ₁₃ ) ₄ N ⁺ , (C ₇ H ₁₅ ) ₄ N ⁺ , (C ₈ H ₁₇ ) ₄ N ⁺ , (C ₉ H ₁₉ ) ₄ N ⁺ , (C ₁₀ H ₂₁ ) ₄ N ^{+ and the} like. In addition, when R ¹ R ² R ³ is all a methyl group, for example, R ⁴ is (C ₂ H ₅ ), (C ₆ H ₁₃ ), (C ₈ H ₁₇ ), (C ₉ H ₁₉ ), Examples of the compound include (C ₁₀ H ₂₁ ), (C ₁₂ H ₂₅ ), (C ₁₄ H ₂₉ ), (C ₁₆ H ₃₃ ), and (C ₁₈ H ₃₇ ). Further, when all of R ¹ R ² are methyl groups, for example, all of R ³ R ⁴ are (C ₈ H ₁₇ ), (C ₁₀ H ₂₁ ), (C ₁₂ H ₂₅ ), (C ₁₄ H ₂₉ ). , (C ₁₆ H ₃₃ ), (C ₁₈ H ₃₇ ) and the like. Furthermore, examples of the case where R ¹ is a methyl group include compounds in which R ² R ³ R ⁴ are all (C ₄ H ₉ ), (C ₈ H ₁₇ ), and the like.

By the way, it is desired that the hydrophilic oil repellent has durability against water and the durability of the hydrophilic oil repellent effect in uses such as a porous water-absorbing evaporating material that is used in contact with water. From the above viewpoint, the nitrogen-containing fluorine-based compound used in the present embodiment is desirably a hardly soluble compound having low solubility in water. That is, when the hydrophilic imparting group X is an anion type, the counter ion M ¹ is preferably an alkaline earth metal, Mg, Al, and Ca, Ba, Mg are particularly excellent in hydrophilic oil repellency, It is preferable because of its low solubility in water.

(Cation type)
When the hydrophilic imparting group X is a cation type, the above X has “—N ⁺ R ⁵ R ⁶ R ⁷ • Cl ⁻ ”, “—N ⁺ R ⁵ R ⁶ R ⁷ • Br ⁻ ”, “— ^{N + R 5 R 6 R 7} · I - "" ^{- N + R 5 R 6 R} 7 · CH 3 SO 3 - , "" ^{- N + R 5 R 6 R} 7 · R 7 SO 4 - "," ^{-N + R 5 R 6 R 7} · NO 3 - "," ^{(- N + R 5 R 6} R 7) 2 CO 3 2- "or" ^{(-N + R 5 R 6 R} 7) 2 SO 4 2 ⁻ ”(R ^{5 to} R ⁷ are each a hydrogen atom or an independent linear or branched alkyl group having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms). Here, it is preferable that the number of carbon atoms is 20 or less because the hydrophilic oil repellency is not impaired.

(Bisexual)
In the case where the hydrophilic imparting group X is an amphoteric type, the above-mentioned X is at the end of the carboxybetaine type “—N ⁺ R ⁸ R ⁹ (CH ₂ ) _n CO ₂ ⁻ ”, and the sulfobetaine type “—N ⁺ R”. ⁸ R ⁹ (CH ₂ ) _n SO ₃ ⁻ ”, amine oxide type“ —N ⁺ R ⁸ R ⁹ O ⁻ ”, or phosphobetaine type“ —OPO ₃ ^— (CH ₂ ) _n N ⁺ R ⁸ R ⁹ R ”. ¹⁰ "or" _{^{-N + R 8 R 9 (CH}} 2) n OPO 3 - R 11 "(n is an integer of from 1 to ^{5, R 8, R 9, R} 10 is a hydrogen atom or independent 1 carbon atoms 12 linear or branched alkyl groups, and R ¹¹ is a linear or branched alkyl group having 1 to 12 carbon atoms. Here, it is preferable that the number of carbon atoms is 12 or less because the hydrophilic oil repellency is not impaired.

[Cyclic nitrogen-containing fluorine compound]
In the cyclic nitrogen-containing fluorine-based compound represented by the above formula (3) or the above formula (4), a nitrogen-containing perfluoroalkylene group composed of Rf ⁴ , Rf ⁵ and Rf ⁶ and further Z constitutes an oil repellency-imparting group. To do.
Further, in the nitrogen-containing fluorine-based compound represented by the above formula (3) or the above formula (4), the total number of carbons bonded with fluorine in Rf ^{4 to} Rf ⁶ and Z which are the oil repellency-imparting groups is 4 to 4. A range of 18 is preferable, and a range of 5 to 12 is preferable. If the number of carbons to which fluorine is bonded is less than 4, it is not preferable because the oil repellent effect is insufficient.

Here, in the above formula (4), R is a linking group that connects the oil repellency-imparting group and the hydrophilicity-imparting group in the molecular chain. The structure of the linking group R is not particularly limited as long as it is a divalent organic group. Specific examples of the linking group R include, for example, an oxygen atom [—O—], a carbonyl group [—C (═O) —], an imino group [—NH—], and a sulfonyl group [—S (═O). _2— ], —OP (═O) (O ⁻ ) O— group, hydrocarbon group having 1 to 20 carbon atoms, and combinations thereof. The linking group R may contain one or more selected from a polyoxyalkylene group and an epoxy group. The hydrocarbon group may be a saturated hydrocarbon group or an unsaturated hydrocarbon group. The hydrocarbon group may be a chain hydrocarbon group or a cyclic hydrocarbon group. The chain hydrocarbon group may be linear or branched. Examples of the hydrocarbon group include an alkylene group, an alkenylene group, and an arylene group. The imino group and the hydrocarbon group may have a substituent.

  The linking group R may or may not contain one or more types of bonds selected from ether bonds, ester bonds, amide bonds and urethane bonds in the molecular chain. The amide bond includes a carboxylic acid amide bond and a sulfonamide bond. The ester bond includes a carboxylic acid ester bond, a sulfonic acid ester bond, and a phosphate ester bond.

Moreover, in said formula (3) or said formula (4), X is any one hydrophilicity imparting group selected from the group which consists of an anionic type, a cationic type, and an amphoteric type.
Examples of the anionic, cationic, and amphoteric hydrophilic imparting groups are the same as those exemplified for the linear (or branched) nitrogen-containing fluorine-based compound.

<Binder>
In the porous water-absorbing and evaporating material 1 of the present embodiment, the hydrophilic oil-repellent agent may be bound to the porous body with a binder in order to make the hydrophilic oil-repellent agent stably exist on the surface of the continuous pores. As the binder, one or both of an organic binder and an inorganic binder can be used.

  As the organic binder (resin), a thermoplastic resin, a thermoplastic elastomer, a thermosetting resin, a UV curable resin, or the like can be used. Specific examples of the organic binder include polyvinyl chloride, polyethylene, polypropylene, polycarbonate, polyester, polystyrene, silicone resin, polyvinyl acetal, polyvinyl alcohol, acrylic polyol resin, polyester polyol resin, urethane resin, fluororesin, and thermoplastic resin. Thermosetting resins such as thermoplastic resins such as acrylic resins, epoxy resins, phenol resins, thermosetting acrylic resins, and the like can be given.

  A hydrophilic polymer can be used as the organic binder. As the hydrophilic polymer, those containing a hydroxyl group are preferred. Specific examples of the hydrophilic polymer include polysaccharides such as polyvinyl alcohol, polyvinyl butyral, cellulose, and derivatives thereof. These may be used alone or in combination of two or more. The hydrophilic polymer may be crosslinked with a crosslinking agent. By crosslinking the hydrophilic polymer (organic binder), the bond between the hydrophilic oil repellent and the porous body is strengthened.

  The crosslinking agent is not particularly limited and can be appropriately selected depending on the purpose. Specific examples of the crosslinking agent include epoxy compounds, isocyanate compounds, aldehyde compounds, ultraviolet crosslinking compounds, leaving group-containing compounds, carboxylic acid compounds, urea compounds, and the like.

Specifically, as the inorganic binder (inorganic glass), for example, trialkoxysilane represented by the chemical formula [R ¹⁴ Si (OR ¹⁵ ) ₃ ], chemical formula [Si (OR ¹⁶ ) ₄ ] (R ^{14 to} R ¹⁶ And silane compounds such as tetraalkoxysilane, water glass and the like, each of which is an independent alkyl group having 1 to 6 carbon atoms. Among these, water glass is preferable because the effect of improving durability is high.

  The mass composition ratio of the hydrophilic oil repellent and the binder is preferably in the range of 0.2 to 99.9 to 99.8 to 0.1, more preferably 2 to 98 to 98 to 2, and even more preferably. 10-90 vs. 90-10. Here, it is preferable that the mass composition ratio of the hydrophilic oil repellent agent is 0.2 or more because hydrophilic oil repellency can be sufficiently obtained. In consideration of the binding property to the porous body and the durability of the hydrophilic oil repellent, 10 to 90 to 90 to 10 is particularly preferable.

  The porous water-absorbing evaporating material 1 may contain chemicals such as a fungicide, an antibacterial agent and a bactericidal agent. These chemicals may be added to the porous body that is the base material of the porous water-absorbing and evaporating material 1, or may be added to the hydrophilic oil repellent.

<Method for producing porous water-evaporating material>
The porous water-absorbing evaporating material 1 can be produced, for example, by applying a coating liquid containing a hydrophilic oil repellent to the surface of a porous body that is a base material and drying it.

  As the coating liquid, a solution in which a hydrophilic oil repellent is dissolved in a solvent or a dispersion in which the hydrophilic oil repellent is dispersed can be used. The coating solution preferably contains the above-described binder. As a solvent for the coating solution, water, an organic solvent, or a mixture of water and an organic solvent can be used. Examples of the organic solvent include methanol, ethanol, IPA, tetrahydrofuran, hexane, chloroform, toluene, ethyl acetate, DMSO, DMF, acetone, a fluorine-based solvent, and the like. In particular, water, alcohols such as methanol, ethanol, and IPA, or a mixture of water and alcohols are preferable from the viewpoint of easy drying and use, and environmental impact. The mass composition ratio of the hydrophilic oil repellent and water or the organic solvent in the coating solution is preferably 0.2 to 50.0 to 99.8 to 50.0, more preferably 1.0 to 30.0 to 99.0. ~ 70.0. If the mass composition ratio of the hydrophilic oil repellent in the coating solution is less than 0.2, the entire substrate may not be sufficiently hydrophilic and oil repellent, which is not preferable. On the other hand, if the mass composition ratio of the hydrophilic oil repellent in the coating solution exceeds 50.0, it is not preferable because the solution dispersion stability of the surface coating material is easily impaired. In consideration of applicability and durability of the product, 1.0 to 30.0 is preferably 99.0 to 70.0.

  As a method for applying the coating liquid to the surface of the porous body, a method such as a dipping method, a spray method, a printing method, a roller method, or the like can be used. Agents such as fungicides, antibacterial agents, and bactericides may be added to the coating solution to impart hydrophilic oil repellency to the porous body, and to impart antifungal and antibacterial properties.

<Use of porous water-absorbing evaporation material>
The porous water-absorbing evaporating material 1 can be used as, for example, an evaporating / removing material for drain water of a refrigerator and a water vapor generating material for a humidifier. When using as a drain water evaporation removal material of a refrigerator, the porous water-absorbing evaporation material 1 is disposed so that the lower portion thereof is in contact with the water in the drain water tank of the refrigerator. When used as a material for generating water vapor in the humidifier, the porous water-absorbing evaporating material 1 is arranged so that the lower part thereof is in contact with the water in the humidifying water tank of the humidifier. Since the porous water-absorbing evaporating material 1 sucks up water using the capillary phenomenon, the speed of sucking up water becomes almost constant regardless of the contact time with water. For this reason, by installing the porous water-absorbing evaporating material 1 in a container containing water and arranging it in the room, the room can be stably moisturized while water is present in the container.

  In FIG. 1, a plurality of porous water-absorbing and evaporating materials 1 form a unit, but one porous water-absorbing and evaporating material 1 can be used alone. For example, the porous water-absorbing evaporating material 1 can be used as an evaporating sheet of condensed water that has been adhered to the lower side of the window frame and condensed on the window glass to flow down. Furthermore, the porous water-absorbing evaporating material 1 can also be used as a water-absorbing material for sucking up water accumulated at the bottom of an oil tank such as a gasoline tank, a light oil tank, a kerosene tank, or an oil tank.

(Synthesis Example 1)
“Synthesis of 3- [3-[[perfluoro (2-methyl-3-dibutylaminopropanoyl)] amino] propyl-dimethyl-ammonium] propanesulfonate”
120 g of perfluoro (2-methyl-3-dibutylaminopropionic acid) fluoride obtained by electrolytic fluorination of methyl 2-methyl-3-dibutylaminopropionate was dissolved in a solution of 39 g of dimethylaminopropylamine in 500 ml of IPE solvent. The solution was added dropwise in an ice bath. After stirring at room temperature for 2 hours, filtration was performed, and the IPE layer of the filtrate was washed with an aqueous NaHCO ₃ solution and an aqueous NaCl solution, separated, and then washed with water. Thereafter, IPE was distilled off, and further distilled to obtain 64 g of (C ₄ F ₉ ) ₂ NCF ₂ CF (CF ₃ ) CONHC ₃ H ₆ N (CH ₃ ) ₂ as a crude product (yield 47%). ).

Subsequently, 1.5 g of the obtained (C ₄ F ₉ ) ₂ NCF ₂ CF (CF ₃ ) CONHC ₃ H ₆ N (CH ₃ ) ₂ was stirred in acetonitrile and refluxed with 1,3-propane sultone for 23 hours. Then, reprecipitation was performed in a mixed solvent of fluorinated solvent AK225 (Asahi Glass Co., Ltd.) and IPE to obtain 1.3 g of a sulfobetaine compound represented by the following formula (5) (yield 75%).

(Synthesis Example 2)
“Synthesis of 3- [3-[[perfluoro (2-methyl-3-dibutylaminopropanoyl)] amino] propyl-dimethyl-ammonium] 2-hydroxypropane-1-sulfonate”
120 g of perfluoro (2-methyl-3-dibutylaminopropionic acid) fluoride obtained by electrolytic fluorination of methyl 2-methyl-3-dibutylaminopropionate was dissolved in a solution of 39 g of dimethylaminopropylamine in 500 ml of IPE solvent. The solution was added dropwise in an ice bath. After stirring at room temperature for 2 hours, filtration was performed, and the IPE layer of the filtrate was washed with an aqueous NaHCO ₃ solution and an aqueous NaCl solution, separated, and then washed with water. Thereafter, IPE was distilled off, and further distilled to obtain 64 g of (C ₄ F ₉ ) ₂ NCF ₂ CF (CF ₃ ) CONHC ₃ H ₆ N (CH ₃ ) ₂ as a crude product (yield 47%). ).

Next, 5.0 g of the obtained (C ₄ F ₉ ) ₂ NCF ₂ CF (CF ₃ ) CONHC ₃ H ₆ N (CH ₃ ) ₂ , 2.0 g of sodium 3-chloro-2-hydroxypropanesulfonate, ethanol 10 ml and 2.1 g of water were mixed and refluxed for 20 hours. Thereafter, 0.7 g of sodium carbonate was added and the mixture was further refluxed for 4 hours. After completion of the reaction, the reaction solution was poured into water, and the precipitated solid was reprecipitated in a fluorine solvent AK225 (manufactured by Asahi Glass Co., Ltd.) and an IPE mixed solvent to obtain a sulfobetaine compound represented by the following formula (6). 0.5 g was obtained (yield 59%).

(Synthesis Example 3)
“Synthesis of 2- [3-[[perfluoro (2-methyl-3-morpholinopropanoyl)] amino] propyl-dimethyl-ammonium] acetate”
An ice bath was used in a solution of 21 g of perfluoro (3-methyl-3-morpholinopropionic acid) fluoride obtained by electrofluorination of methyl 2-methyl-3-morpholinopropionate and 10 g of dimethylaminopropylamine dissolved in 100 ml of IPE solvent. It was dripped under. Thereafter, the mixture was stirred at room temperature for 2 hours and then filtered, and the IPE layer of the filtrate was washed with an aqueous NaHCO ₃ solution and an aqueous NaCl solution, separated and washed with water, and then the IPE was distilled off. As a product, 22 g of O (CF ₂ CF ₂ ) ₂ NCF ₂ CF (CF ₃ ) CONHC ₃ H ₆ N (CH ₃ ) ₂ was obtained (crude yield 88%).

The obtained crude product O (CF ₂ CF ₂ ) ₂ NCF ₂ CF (CF ₃ ) CONHC ₃ H ₆ N (CH ₃ ) ₂ was refluxed overnight with 3 g of sodium monochloroacetate under stirring in ethanol. 11 g of a carboxybetaine compound represented by the following formula (7) was obtained (yield 99%).

(Synthesis Example 4)
“Synthesis of 2- [3-[[perfluoro (2-methyl-3-dibutylaminopropanoyl)] amino] propyl-dimethyl-ammonium] acetate”
120 g of perfluoro (2-methyl-3-dibutylaminopropionic acid) fluoride obtained by electrolytic fluorination of methyl 2-methyl-3-dibutylaminopropionate was dissolved in a solution of 39 g of dimethylaminopropylamine in 500 ml of IPE solvent. The solution was added dropwise in an ice bath. After stirring at room temperature for 2 hours, filtration was performed, and the IPE layer of the filtrate was washed with an aqueous NaHCO ₃ solution and an aqueous NaCl solution, separated, and then washed with water. Thereafter, IPE was distilled off, and further distilled to obtain 64 g of (C ₄ F ₉ ) ₂ NCF ₂ CF (CF ₃ ) CONHC ₃ H ₆ N (CH ₃ ) ₂ as a crude product (yield 47%). ).

Subsequently, 8 g of the obtained (C ₄ F ₉ ) ₂ NCF ₂ CF (CF ₃ ) CONHC ₃ H ₆ N (CH ₃ ) ₂ was refluxed with sodium monochloroacetate in ethanol overnight with stirring, filtered and concentrated. 9 g of a carboxybetaine compound represented by the following formula (8) was obtained (yield 99%).

(Examples 1-5)
Commercially available polyester nonwoven fabric A (weight: 80 g / m ² , thickness: 0.40 mm), polyester nonwoven fabric B (weight: 122 g / m ² , thickness: 0.55 mm), polypropylene nonwoven fabric (weight: 59 g / m ² , thickness: 0.34 mm) was cut into strips each having a width of 25 mm and a length of 180 mm to produce a strip-shaped substrate. Moreover, the nitrogen-containing fluorine-type compound synthesize | combined in the synthesis examples 1-3 as a hydrophilic oil repellent and ethanol were mixed, and the coating liquid whose density | concentration of a nitrogen-containing fluorine-type compound is 2 mass% was prepared.

  The strip-shaped substrate was dipped in the above coating solution, pulled up and air-dried, and then dried at 120 ° C. for 2 hours, whereby the strip-shaped substrate was subjected to a hydrophilic oil-repellent treatment. Thus, the hydrophilic oil-repellent treatment water absorption test piece of Examples 1-5 was produced.

  About Examples 1-5, the kind of the base material used for the column of "base material" of the following Table 1 is the synthesis example of the nitrogen-containing fluorine-type compound dissolved in the coating liquid in the column of "hydrophilic oil repellent". The number is shown in the column “Increase After Drying”, and the amount of increase in the basis weight of the hydrophilic oil-repellent treated water-absorbing test piece prepared by drying the coating solution is shown.

(Water absorption evaluation)
The upper ends of the hydrophilic oil-repellent treated water-absorbing test pieces of Examples 1 to 5 and the respective strip-shaped test pieces (Comparative Examples 1 to 3) cut to the same size that have not been subjected to the hydrophilic oil-repellent treatment are fixed to a horizontal bar with tape, The specimen was suspended vertically. A stainless steel bat containing tap water was placed on the jack, and the bat was raised by operating the jack so that the lower end of the test piece was immersed in water by 5 mm. The height at which the water rose by capillary action after 30 minutes of immersion was measured. The results are shown in Table 1 as “water rising height”.

  From the results of Table 1, all of the hydrophilic oil-repellent treated water-absorbing test pieces (Examples 1 to 5) that were hydrophilic and oil-repellent treated with a nitrogen-containing fluorine-based compound (Examples 1 to 5) were not strip-shaped test pieces (Comparative Example). 1 to 3), the water rising height is clearly higher, which indicates that the water absorption performance is remarkably improved.

(Example 6)
Polyester nonwoven fabric B (weight per unit area: 122 g / m ² , thickness: 0.55 mm) was cut into a strip shape having a width of 15 mm and a length of 150 mm to produce a strip-shaped substrate. Further, 0.8 parts by mass of the nitrogen-containing fluorine-based compound synthesized in Synthesis Example 2 as a hydrophilic oil repellent, and 0.4 parts by mass (SiO ₂ ) of silica sol (manufactured by Nissan Chemical Co., organosilica sol IPA-ST) as an inorganic compound. As a binder, 1.6 parts by mass of polyvinyl butyral (Sekisui Chemical Co., Ltd., ESREC BL-1) as a binder, mixed solvent (hexafluoroxylene 57% by mass, ethanol 38% by mass, n-butanol 5% by mass) Were mixed at a ratio of 96.3 parts by mass to prepare a coating solution.

  The strip-shaped substrate was immersed in the coating solution, pulled up and air-dried, and then dried at 120 ° C. for 2 hours to prepare a hydrophilic oil-repellent water absorption test piece of Example 6.

(Example 7)
A nitrogen-containing material synthesized in Synthesis Example 4 as a hydrophilic oil-repellent agent using a strip-shaped substrate obtained by cutting a polyester nonwoven fabric C (weight: 247 g / m ² , thickness: 0.85 mm) into a strip shape as a strip-shaped substrate. A hydrophilic oil-repellent treated water-absorbing test piece of Example 7 was produced in the same manner as Example 6 except that a fluorine-based compound was used.

(Example 8)
Example 8 was carried out in the same manner as in Example 6 except that a strip-shaped base material obtained by cutting a polypropylene nonwoven fabric (weight per unit: 59 g / m ² , thickness: 0.34 mm) into a strip shape was used as the strip-shaped substrate. A hydrophilic oil-repellent treated water absorption test piece was prepared.

Example 9
Nitrogen-containing fluorine synthesized in Synthesis Example 4 as a hydrophilic oil repellent using a strip-shaped substrate obtained by cutting a polypropylene nonwoven fabric (weight: 59 g / m ² , thickness: 0.34 mm) into a strip shape as a strip-shaped substrate A hydrophilic oil-repellent treated water-absorbing test piece of Example 9 was obtained in the same manner as Example 6 except that the system compound was used.

  About Examples 6-9, the kind of the base material used for the column of "Substrate" in Table 2 below is a synthesis example of the nitrogen-containing fluorine-based compound dissolved in the coating solution in the column of "Hydrophilic oil repellent" The number is shown in the column “Increase After Drying”, and the amount of increase in the basis weight of the hydrophilic oil-repellent treated water-absorbing test piece prepared by drying the coating solution is shown.

(Water absorption / oil repellency test with oil / water mixture)
An oil-water mixture was prepared by adding 5 ml of water and n-hexadecane to a graduated cylinder with a capacity of 50 ml to make the total amount 40 ml. The oil / water mixture was separated into two layers, a lower aqueous layer and an upper n-hexadecane layer, and the liquid depth was 115 mm.
In this oil / water mixture, the hydrophilic oil-repellent treated water-absorbing test pieces of Examples 6 to 9 and the respective strip-shaped test pieces having a width of 15 mm and a length of 150 mm (Comparative Examples 4 to 6) not subjected to the hydrophilic oil-repellent treatment. The test pieces were immersed until the lower end of each test piece was in contact with the bottom of the graduated cylinder, and the state was maintained. The hydrophilic oil-repellent treated water absorption test piece sucked up water immediately after the start of immersion. The height of water uptake from the water / n-hexadecane interface after 15 minutes was measured. On the other hand, the test piece not subjected to hydrophilic oil repellent treatment absorbed n-hexadecane immediately after the start of immersion, but water did not rise even after 15 minutes. The results are shown in Table 2 as “water rising height”.

  From the results in Table 2, it was confirmed that the hydrophilic oil-repellent treated water-absorbing test pieces (Examples 6 to 9) subjected to hydrophilic oil-repellent treatment exhibited water absorbing performance even in the presence of n-hexadecane. On the other hand, none of the strip-shaped test pieces (Comparative Examples 4 to 6) not subjected to hydrophilic oil-repellent treatment was able to absorb water in the presence of n-hexadecane.

  Moreover, about the hydrophilic oil-repellent treatment water absorption test piece of Examples 6-9, when water was further added to the oil-water mixture and it retested, it was confirmed that n-hexadecane is not sucked up but only water is sucked up. It was observed that the water absorption rate at the time of the retest was the same value as the first time, and it could be used repeatedly as a water absorption evaporating material. In addition, in any of the hydrophilic oil-repellent treatment water absorption test pieces of Examples 6 to 9, the initial stage (a state immediately after the start of immersion in the oil / water mixture) and the final stage (a state in which almost all the water in the oil / water mixture has been sucked up) The water absorption rate was almost constant.

(Water absorption and oil repellency test)
(Example 10)
In a beaker having a capacity of 30 ml, 10.0 g of water and 15.2 g of n-hexadecane were added to prepare an oil / water mixture. The oil / water mixture was separated into two layers, a lower aqueous layer and an upper n-hexadecane layer.
The beaker was left in a room maintained at a temperature of 20 to 24 ° C. and a humidity of 42 to 45%. The hydrophilic / oil-repellent-treated water-absorbing test piece (weight 0.32 g) of Example 6 was immersed in the oil / water mixture in the beaker so that the lower end of the test piece was in contact with the bottom of the beaker, and the state was maintained. The length of the test piece exposed from the liquid surface of the oil / water mixture (hereinafter referred to as the exposed length) was 120 mm. After immersion for 24 hours, the moisture in the beaker decreased, and the exposed length of the test piece was 126 mm.
The test piece was taken out from the oil / water mixture and its weight was measured to find 0.92 g. Further, when the water layer in the oil / water mixture in the beaker was sucked with a dropper and weighed, 2.58 g of water remained. The evaporation rate of water per average exposed area of the test piece (the average value of the exposed area of the test piece immediately after immersion and the exposed area of the test piece after 24 hours of immersion) was 154 g / m ² · hour.

(Example 11)
An oil / water mixture was prepared by putting 10.0 g of water and 15.0 g of n-hexadecane into a 30 ml beaker, and the hydrophilic oil-repellent water absorption test piece (weight 0.66 g) of Example 7 was used. The water absorption and oil repellency evaporation test was conducted in the same manner as in No. 10. After immersion for 24 hours, the exposed length of the test piece was 126 mm. The weight of the test piece was 1.57 g. Water in the beaker was sucked with a dropper and weighed, and 3.13 g of water remained. The evaporation rate of water per average exposed area of the test piece was 135 g / m ² · hour.

DESCRIPTION OF SYMBOLS 1 Porous water absorption evaporating material 2 Fixing tool 3 Recessed part

Claims (8)

  A porous water-absorbing and evaporating material comprising a porous body having continuous pores, wherein a fluorine-based compound having an oil repellency-imparting group and a hydrophilicity-imparting group is present on at least a part of the surface of the continuous pores. Porous water-absorbing evaporating material. The said fluorine-type compound is 1 type, or 2 or more types of nitrogen-containing fluorine-type compounds shown by any one of following formula (1)-(4), It is characterized by the above-mentioned. Porous water-absorbing evaporation material:

In the above formulas (1) and (2), Rf ¹ and Rf ² are the same or different, each having 1 to 6 carbon atoms and a linear or branched perfluoroalkyl group, and Rf ³ is carbon A number 1-6, which is a linear or branched perfluoroalkylene group;
In the above formulas (3) and (4), Rf ⁴ , Rf ⁵ and Rf ⁶ are the same or different, each having 1 to 6 carbon atoms and a linear or branched perfluoroalkylene group, and Z is Any one of an oxygen atom, a nitrogen atom, a CF ₂ group and a CF group;
In the above formulas (2) and (4), R is a linking group that is a divalent organic group;
Moreover, in said formula (1)-(4), X is any one hydrophilicity imparting group selected from the group which consists of an anionic type, a cationic type, and an amphoteric type.   The porous water-evaporating material according to claim 1 or 2, wherein the fluorine-based compound is bonded to the porous body by one or both of an organic binder and an inorganic binder.   The porous water-absorbing and evaporating material according to claim 3, wherein the organic binder includes any one of a thermoplastic resin, a thermoplastic elastomer, a thermosetting resin, and a UV curable resin.   The porous water-absorbing and evaporating material according to any one of claims 1 to 4, wherein the porous body is a fiber aggregate, a foamed resin molded body, or a ceramic sintered body.   6. The porous water-absorbing and evaporating material according to claim 5, wherein the aggregate of fibers is an aggregate of organic fibers.   The porous water-absorbing material according to claim 6, wherein the organic fiber is a synthetic fiber, a natural fiber or a cellulosic fiber. The porous water absorption according to any one of claims 1 to 7, wherein the porous body is formed into a flat plate shape, a corrugated plate shape, a cylindrical shape, a column shape, or a honeycomb shape. Evaporating material.

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