JP2009079889A - Fin material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fin material having a sufficient hydrophilic property and capable of maintaining its effect sufficiently long, particularly, an aluminum fin material for a heat exchanger. <P>SOLUTION: This fin material is provided by coating a base material surface with a hydrophilic composition. The fin material is characterized in that in a coating surface, the maximum height Rmax of a projection is set to 0.1 μm-2 μm, and a contact angle to water in any before and after being soaked in water of 30°C for 500 hours, is set to 15°C or below. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a fin material, particularly an aluminum fin material useful as a heat exchanger.

In a heat exchanger used for an air conditioner or the like, the condensed water generated at the time of cooling becomes water droplets and stays between the fins, so that a bridge of water is generated and the cooling capacity is lowered. In addition, the adhering of dust or the like between the fins similarly reduces the cooling capacity.
In order to solve these problems, it is known to treat the fin material surface of the heat exchanger with a hydrophilic composition.

For example, Patent Document 1 discloses (A) a polymerizable vinyl group-containing aqueous silica dispersion obtained by reacting a water-dispersible silica with a polymerizable vinylsilane monomer containing a hydrolyzable alkoxysilane group, and polymerizable unsaturated monomers. Reaction product of organic-inorganic composite, (B) curing agent, (C) hydroxyl group-containing polyester resin, (D) pyrithione antibacterial and antifungal agent, (E) silicone emulsion, and (F) amine An aluminum heat exchanger fin formed by applying a hydrophilization treatment composition containing the composition to the surface is disclosed.
In Patent Document 2, the surface of all or part of the metal surface coated with a hydrophilic substance has a fine concavo-convex structure, the concavo-convex structure has a height of 300 μm or less, and the concavo-convex structure 1 cm ^{2 in} plan view. A fin for a heat exchanger having a surface-treated metal having an actual surface area of 2 cm ² or more and a contact area of 0.3 cm ² or less per 1 cm ^{2 of the} rigid body surface when a smooth rigid body is applied to the surface of the uneven structure. It is disclosed.
Patent Document 3 mainly includes an alkali silicate (A), a low molecular organic compound (B) having a carbonyl group, an acrylamide copolymer or a salt thereof (C), and a silane coupling agent (S). An aluminum heat exchanger in which a hydrophilic film as a component is provided on the surface of a fin is disclosed.
Patent Document 4 contains a polymeric antibacterial agent and fine particles, has an elution amount of 0.2 g / m ² or less when immersed in water at 40 ° C. for 120 hours, and a water contact angle of 25 ° or less. There is disclosed an antibacterial composition for laminating fins for heat exchangers, which is a certain antibacterial composition and has a contact angle of water of 25 ° or less after being immersed in water at 40 ° C. for 120 hours.
However, these fin materials do not have sufficient hydrophilicity and have insufficient effects. In addition, there was also an insufficient aspect in hydrophilic sustainability.
JP 7-268209 A JP 10-26491 A JP-A-6-93209 JP 2000-191419 A

  An object of the present invention is to solve the conventional problems as described above, and to provide a fin material that has sufficient hydrophilicity and has a sufficiently long effect, and in particular, an aluminum fin material for a heat exchanger. .

The above problems have been solved by the following means.
1. A fin material in which a hydrophilic composition is coated on a substrate, and the coating surface has a maximum height Rmax of a protrusion of 0.1 μm to 2 μm, and was immersed before and after being immersed in water at 30 ° C. for 500 hours. A fin material having a contact angle with water of 15 ° or less in any of the latter.
2. 2. The fin material according to 1 above, wherein the hydrophilic composition contains 50% by mass or more of a hydrophilic polymer as a solid content.
3. 3. The fin material as described in 1 or 2 above, wherein the substrate is made of aluminum.
4). The above-mentioned 1-3, wherein the hydrophilic polymer has at least one of a structure represented by the following general formula (IV-a) and a structure represented by the general formula (IV-b): The fin material according to any one of the above.

In general formulas (IV-a) and (IV-b), R ^{1 to} R ⁸ each independently represents a hydrogen atom or a hydrocarbon group having 8 or less carbon atoms. L ¹ represents a single bond or a polyvalent organic linking group. L ² represents a polyvalent organic linking group having one or more structures selected from the group consisting of a single bond, —CONH—, —NHCONH—, —OCONH—, —SO ₂ NH—, and —SO ₃ —. . m represents an integer of 1 to 3. x and y represent composition ratios, and 0 <x <100 and 0 <y <100. X represents —OH, —OR _a , —COR _a , —CO ₂ R _e , —CON (R _a ) (R _b ), —N (R _a ) (R _b ), —NHCOR _d , —NHCO ₂ R _a , —OCON (R _a ) (R _b ), —NHCON (R _a ) (R _b ), —SO ₃ R _e , —OSO ₃ R _e , —SO ₂ R _d , —NHSO ₂ R _d , —SO ₂ N (R _a ) (R _b ), —N (R _a ) (R _b ) (R _c ), —N (R _a ) (R _b ) (R _c ) (R _g ), —PO ₃ (R _e) ) (R _f ), —OPO ₃ (R _e ) (R _f ), or —PO ₃ (R _d ) (R _e ). Here, R _a , R _b and R _c each independently represent a hydrogen atom or a linear, branched or cyclic alkyl group, R _d represents a linear, branched or cyclic alkyl group, R _e and R _f independently represents a hydrogen atom or a linear, branched or cyclic alkyl group, an alkali metal, an alkaline earth metal, or onium, and R _g represents a linear, branched or cyclic alkyl group, a halogen atom, An inorganic anion or an organic anion is represented. )
5). 5. The fin material as described in any one of 1 to 4 above, wherein the hydrophilic composition contains an alkoxide compound containing any element selected from Si, Ti, Zr, and Al.
6). It consists of the fin material in any one of said 1-5, The fin material for heat exchangers characterized by the above-mentioned.

The fin material of the present invention has a water contact angle of 15 ° or less before and after being immersed in water at 30 ° C. for 500 hours, and has a high hydrophilicity that has not been conventionally obtained. For this reason, when the fin material is used as a heat exchanger for an air conditioner, it does not form a bridge of water during cooling, and even if dust adheres to the fin, it is cleaned by washing the fin surface with condensed water. There is also an effect. Moreover, even after being immersed in water for a long period of time, the contact angle of water is 15 ° or less, high hydrophilicity can be maintained for a long period of time, and durability is excellent.
Furthermore, the maximum height Rmax of the protrusion on the coating surface of the present invention is 0.1 μm to 2 μm, and it is possible to maintain sufficient hydrophilicity and heat exchange efficiency.

The present invention is described in detail below.
The fin material of the present invention is obtained by coating a hydrophilic composition on a substrate. Preferably, the hydrophilic composition contains 50% by mass or more, preferably 70 to 95% by mass of a hydrophilic polymer as a solid content. Is included.
Preferably, the hydrophilic composition has a hydrophilic polymer chain and is formed by hydrolysis and polycondensation of an alkoxide (also referred to as a metal alkoxide) of an element selected from Si, Ti, Zr, and Al. A coating having a crosslinked structure (also referred to as a hydrophilic film, a hydrophilic layer, or a hydrophilic layer) is formed. The hydrophilic layer having such a crosslinked structure includes a metal alkoxide compound described in detail later and a hydrophilic property. It can be suitably formed using a compound having a hydrophilic functional group capable of forming a graft chain and an appropriate catalyst. Among metal alkoxides, Si alkoxides are preferable from the viewpoint of reactivity and availability, and specifically, compounds used for silane coupling agents can be suitably used.

  In the present invention, the above-described crosslinked structure formed by hydrolysis and polycondensation of the metal alkoxide is hereinafter appropriately referred to as a sol-gel crosslinked structure. Below, each component contained in the hydrophilic coating liquid composition for forming the hydrophilic layer which is this preferable aspect is demonstrated.

[Hydrophilic polymer]
A preferred hydrophilic polymer used in the present invention is a polymer having a hydrophilic group and a group that forms a bond with a metal alkoxide compound selected from Si, Ti, Zr, and Al by the action of a catalyst or the like. . The hydrophilic group is preferably a carboxy group, an alkali metal salt of a carboxy group, a sulfonic acid group, an alkali metal salt of a sulfonic acid group, a hydroxyl group, an amide group, a carbamoyl group, a sulfonamide group, a sulfamoyl group or the like. Can be mentioned. These groups may be present at any position in the polymer. A polymer structure in which a plurality of polymers are bonded directly from a polymer main chain or via a linking group, or bonded to a polymer side chain or a graft side chain, is preferred. Examples of the group that forms a bond with the metal alkoxide compound by the action of a catalyst include a carboxyl group, an alkali metal salt of a carboxy group, a carboxylic anhydride group, an amino group, a hydroxy group, an epoxy group, a methylol group, a mercapto group, an isocyanate group, Examples thereof include reactive groups such as a block isocyanate group, an alkoxysilyl group, an alkoxytitanate group, an alkoxyaluminate group, an alkoxyzirconate group, an ethylenically unsaturated group, an ester group, and a tetrazole group. The polymer structure having a hydrophilic group and a group that forms a bond with a metal alkoxide compound by the action of a catalyst or the like includes an ethylenically unsaturated group (for example, an acrylate group, a methacrylate group, an itaconic acid group, a crotonic acid group, a cinnamic acid group). Styrene group, vinyl group, allyl group, vinyl ether group, vinyl ester group, etc.), polymer obtained by vinyl polymerization, polycondensation polymer such as polyester, polyamide, polyamic acid, etc., addition polymer such as polyurethane, etc. Preferred examples include natural cyclic polymer structures such as cellulose, amylose and chitosan. A polymer having at least one of the structure represented by the general formula (IV-a) and the structure represented by the general formula (IV-b) (hereinafter referred to as a specific hydrophilic polymer) is preferable.

In general formulas (IV-a) and (IV-b), R ^{1 to} R ⁸ each independently represents a hydrogen atom or a hydrocarbon group having 8 or less carbon atoms. L ¹ represents a single bond or a polyvalent organic linking group. L ² represents a polyvalent organic linking group having one or more structures selected from the group consisting of a single bond, —CONH—, —NHCONH—, —OCONH—, —SO ₂ NH—, and —SO ₃ —. . m represents an integer of 1 to 3. x and y represent composition ratios, and 0 <x <100 and 0 <y <100. X represents —OH, —OR _a , —COR _a , —CO ₂ R _e , —CON (R _a ) (R _b ), —N (R _a ) (R _b ), —NHCOR _d , —NHCO ₂ R _a , —OCON (R _a ) (R _b ), —NHCON (R _a ) (R _b ), —SO ₃ R _e , —OSO ₃ R _e , —SO ₂ R _d , —NHSO ₂ R _d , —SO ₂ N (R _a ) (R _b ), —N (R _a ) (R _b ) (R _c ), —N (R _a ) (R _b ) (R _c ) (R _g ), —PO ₃ (R _e) ) (R _f ), —OPO ₃ (R _e ) (R _f ), or —PO ₃ (R _d ) (R _e ). Here, R _a , R _b and R _c each independently represent a hydrogen atom or a straight chain (preferably having 1 to 8 carbon atoms), a branched or cyclic alkyl group, and R _d is a straight chain (preferably carbon 1 to 8) represents a branched or cyclic alkyl group, and R _e and R _f each independently represent a hydrogen atom or a straight chain (preferably having 1 to 8 carbon atoms), a branched or cyclic alkyl group, an alkali metal, An alkaline earth metal or onium is represented, and R _g represents a linear (preferably having 1 to 8 carbon atoms), branched or cyclic alkyl group, a halogen atom, an inorganic anion, or an organic anion. )

In the case where R ^{1 to} R ⁸ represent a hydrocarbon group, the hydrocarbon group is preferably a hydrocarbon group having 8 or less carbon atoms, and examples thereof include an alkyl group and an aryl group. Or a cyclic alkyl group is preferable. Specifically, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, isopropyl group, isobutyl group, s-butyl group, t-butyl group, isopentyl group, neopentyl group 1-methylbutyl group, isohexyl group, 2-ethylhexyl group, 2-methylhexyl group, cyclopentyl group and the like.
R ^{1 to} R ⁸ are preferably a hydrogen atom, a methyl group, or an ethyl group from the viewpoints of effects and availability.

  These hydrocarbon groups may further have a substituent. When the alkyl group has a substituent, the substituted alkyl group is composed of a bond between the substituent and the alkylene group, and a monovalent nonmetallic atomic group excluding hydrogen is used as the substituent. Preferred examples include halogen atoms (-F, -Br, -Cl, -I), hydroxyl groups, alkoxy groups, aryloxy groups, mercapto groups, alkylthio groups, arylthio groups, alkyldithio groups, aryldithio groups, amino groups, N-alkylamino group, N, N-diarylamino group, N-alkyl-N-arylamino group, acyloxy group, carbamoyloxy group, ア ル キ ル -alkylcarbamoyloxy group, N-arylcarbamoyloxy group, N, N-dialkyl Carbamoyloxy group, N, N-diarylcarbamoyloxy group, N-alkyl-N-reelcarbamoyloxy group, alkylsulfoxy group, arylsulfoxy group, acylthio group, acylamino group, N-alkylacylamino group, N-aryl Acylamino group, ureido group, N ′ Alkylureido group, N ′, N′-dialkylureido group, N′-arylureido group, N ′, N′-diarylureido group, N′-alkyl-N′-arylureido group, N-alkylureido group, N -Arylureido group, N'-alkyl-N-alkylureido group, N'-alkyl-N-arylureido group, N ', N'-dialkyl-N-alkylureate group, N', N'-dialkyl- N-arylureido group, N′-aryl-Ν-alkylureido group, N′-aryl-N-arylureido group, N ′, N′-diaryl-N-alkylureido group, N ′, N′-diaryl- N-arylureido group, N′-alkyl-N′-aryl-N-alkylureido group, N′-alkyl-N′-aryl-N-arylureido group Alkoxycarbonylamino group, aryloxycarbonylamino group, N-alkyl-N-alkoxycarbonylamino group, N-alkyl-N-aryloxycarbonylamino group, N-aryl-N-alkoxycarbonylamino group, N-aryl-N -Aryloxycarbonylamino group, formyl group, acyl group, carboxyl group, alkoxycarbonyl group,

Aryloxycarbonyl group, carbamoyl group, N-alkylcarbamoyl group, N, N-dialkylcarbamoyl group, N-arylcarbamoyl group, N, N-diarylcarbamoyl group, N-alkyl-N-arylcarbamoyl group, alkylsulfinyl group, Arylsulfinyl group, alkylsulfonyl group, arylsulfonyl group, sulfo group (—SO ₃ H) and its conjugate base group (hereinafter referred to as sulfonate group), alkoxysulfonyl group, aryloxysulfonyl group, sulfinamoyl group, N-alkyls Rufinamoyl group, N, N-dialkylsulfinamoyl group, N-arylsulfinamoyl group, N, N-diarylsulfinamoyl group, N-alkyl-N-arylsulfinamoyl group, sulfamoyl group, N-alkylsulfur group Sulfamoyl group, N, N- dialkylsulfamoyl group, N- aryl sulfamoyl group, N, N- diaryl sulfamoyl group, N- alkyl -N- arylsulfamoyl group phosphono group _(-PO 3 _{H 2} ) And conjugated base groups thereof (hereinafter referred to as phosphonate groups), dialkyl phosphono groups (—PO ₃ (alkyl) ₂ ), diaryl phosphono groups (—PO ₃ (aryl) ₂ ), alkylaryl phosphono groups (— PO3 (alkyl) (aryl)), a monoalkyl phosphono group (—PO ₃ H (alkyl)) and a conjugate base group thereof (hereinafter referred to as an alkyl phosphonate group), a monoaryl phosphono group (—PO ₃ H ( aryl)) and its conjugated base group (hereinafter referred to as aryl phosphonophenyl group), phosphonooxy group (-OPO H ₂₎ and its conjugated base group (hereinafter referred to as phosphonophenyl group), dialkyl phosphonooxy group _(-OPO 3 _(alkyl) 2), diaryl phosphonooxy group _(-OPO 3 _(aryl) 2), alkyl An arylphosphonooxy group (—OPO (alkyl) (aryl)), a monoalkylphosphonooxy group (—OPO ₃ H (alkyl)) and its conjugate base group (hereinafter referred to as an alkylphosphonatooxy group), monoaryl Examples include a phosphonooxy group (—OPO ₃ H (aryl)) and its conjugate base group (hereinafter referred to as arylphosphonatooxy group), a morpholino group, a cyano group, a nitro group, an aryl group, an alkenyl group, and an alkynyl group. .

Specific examples of the alkyl group in these substituents are the same as those of R ^{1 to} R ⁸ , and specific examples of the aryl group include a phenyl group, a biphenyl group, a naphthyl group, a tolyl group, Xylyl, mesityl, cumenyl, chlorophenyl, bromophenyl, chloromethylphenyl, hydroxyphenyl, methoxyphenyl, ethoxyphenyl, phenoxyphenyl, acetoxyphenyl, benzoyloxyphenyl, methylthiophenyl , Phenylthiophenyl group, methylaminophenyl group, dimethylaminophenyl group, acetylaminophenyl group, carboxyphenyl group, methoxycarbonylphenyl group, ethoxyphenylcarbonyl group, phenoxycarbonylphenyl group, N-phenylcarbamo Butylphenyl group include a phenyl group, cyanophenyl group, sulfophenyl group, sulfonatophenyl group, phosphonophenyl phenyl group, a phosphonophenyl phenyl group. Examples of the alkenyl group include vinyl group, 1-propenyl group, 1-butenyl group, cinnamyl group, 2-chloro-1-ethenyl group and the like. Examples of alkynyl group include ethynyl group, 1- A propynyl group, a 1-butynyl group, a trimethylsilylethynyl group, etc. are mentioned. Examples of G ¹ in the acyl group (G ¹ CO—) include hydrogen and the above alkyl groups and aryl groups.

  Among these substituents, more preferred are halogen atoms (—F, —Br, —Cl, —I), alkoxy groups, aryloxy groups, alkylthio groups, arylthio groups, N-alkylamino groups, N, N-dialkyls. Amino group, acyloxy group, N-alkylcarbamoyloxy group, N-arylcarbamoyloxy group, acylamino group, formyl group, acyl group, carboxyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, N-alkylcarbamoyl group N, N-dialkylcarbamoyl group, N-arylcarbamoyl group, N-alkyl-N-arylcarbamoyl group, sulfo group, sulfonate group, sulfamoyl group, N-alkylsulfamoyl group, N, N-dialkylsulfamoyl group Group, N-arylsulfamoy Group, N-alkyl-N-arylsulfamoyl group, phosphono group, phosphonate group, dialkyl phosphono group, diaryl phosphono group, monoalkyl phosphono group, alkyl phosphonate group, monoaryl phosphono group, aryl phosphonate group Group, phosphonooxy group, phosphonatooxy group, aryl group, and alkenyl group.

  On the other hand, the alkylene group in the substituted alkyl group is preferably a divalent organic residue obtained by removing any one of the hydrogen atoms on the alkyl group having 1 to 20 carbon atoms. Preferred examples include linear alkylene groups having 1 to 12 carbon atoms, branched alkylene groups having 3 to 12 carbon atoms, and cyclic alkylene groups having 5 to 10 carbon atoms. Preferable specific examples of the substituted alkyl group obtained by combining the substituent and the alkylene group include chloromethyl group, bromomethyl group, 2-chloroethyl group, trifluoromethyl group, methoxymethyl group, methoxyethoxyethyl group, allyl group. Oxymethyl group, phenoxymethyl group, methylthiomethyl group, tolylthiomethyl group, ethylaminoethyl group, diethylaminopropyl group, morpholinopropyl group, acetyloxymethyl group, benzoyloxymethyl group, N-cyclohexylcarbamoyloxyethyl group, N- Phenylcarbamoyloxyethyl group, acetylaminoethyl group, N-methylbenzoylaminopropyl group, 2-oxyethyl group, 2-oxypropyl group, carboxypropyl group, methoxycarbonylethyl group, allyloxy Rubonirubuchiru group,

  Chlorophenoxycarbonylmethyl group, carbamoylmethyl group, N-methylcarbamoylethyl group, N, N-dipropylcarbamoylmethyl group, N- (methoxyphenyl) carbamoylethyl group, N-methyl-N- (sulfophenyl) carbamoyl Methyl group, sulfobutyl group, sulfonatobutyl group, sulfamoylbutyl group, N-ethylsulfamoylmethyl group, N, N-dipropylsulfamoylpropyl group, N-tolylsulfamoylpropyl group, N-methyl-N- (Phosphonophenyl) sulfamoyloctyl group, phosphonobutyl group, phosphonatohexyl group, diethylphosphonobutyl group, diphenylphosphonopropyl group, methylphosphonobutyl group, methylphosphonatobutyl group, tolylphosphonohexyl group, Torilho Phonatohexyl group, phosphonooxypropyl group, phosphonatoxybutyl group, benzyl group, phenethyl group, α-methylbenzyl group, 1-methyl-1-phenylethyl group, p-methylbenzyl group, cinnamyl group, allyl group 1-propenylmethyl group, 2-butenyl group, 2-methylallyl group, 2-methylpropenylmethyl group, 2-propynyl group, 2-butynyl group, 3-butynyl group and the like.

L ¹ represents a single bond or a polyvalent organic linking group. Here, the single bond means that the polymer main chain and X are directly bonded without a linking chain. Further, the organic linking group refers to a linking group composed of non-metallic atoms, specifically, 0 to 200 carbon atoms, 0 to 150 nitrogen atoms, 0 to 200 oxygen atoms. It consists of atoms, 0 to 400 hydrogen atoms, and 0 to 100 sulfur atoms. More specific examples of the linking group include the following structural units or those formed by combining them.

  Of these, —CONH—, —NHCONH—, and —OCONH—, which are highly hydrophilic, are preferable.

L ¹ may be formed from a polymer or an oligomer, and specifically, preferably includes polyacrylate, polymethacrylate, polyacrylonitrile, polyvinyl, polystyrene, and the like made of an unsaturated double bond monomer. Preferred examples include poly (oxyalkylene), polyurethane, polyurea, polyester, polyamide, polyimide, polycarbonate, polyamino acid, polysiloxane, and the like, and preferably polyacrylate, polymethacrylate, polyacrylonitrile, polyvinyl, and polystyrene. More preferred are polyacrylates and polymethacrylates.
The structural unit used for these polymers and oligomers may be one type or two or more types. In addition, when L ¹ is a polymer or oligomer, the number of constituent elements is not particularly limited, and the molecular weight is preferably 1,000 to 1,000,000, more preferably 1,000 to 500,000, and 1,000 to 200,000 is most preferred.

L ² represents a single bond or a polyvalent organic linking group having one or more structures selected from the group consisting of —CONH—, —NHCONH—, —OCONH—, —SO ₂ NH—, and —SO ₃ —. Here, the single bond represents that the polymer main chain and the Si atom are directly bonded without a linking group. In L ² , two or more of the structures may be present, and in that case, they may be the same as or different from each other. If one or more of the above structures are included, the other structures can have the same structure as that described for L ¹ .

X is a hydrophilic group, and is —OH, —OR _a , —COR _a , —CO ₂ R _e , —CON (R _a ) (R _b ), —N (R _a ) (R _b ), — NHCOR _d , —NHCO ₂ R _a , —OCON (R _a ) (R _b ), —NHCON (R _a ) (R _b ), —SO ₃ R _e , —OSO ₃ R _e , —SO ₂ R _d , — NHSO ₂ R _d , —SO ₂ N (R _a ) (R _b ), —N (R _a ) (R _b ) (R _c ), —N (R _a ) (R _b ) (R _c ) (R _g ) ), —PO ₃ (R _e ) (R _f ), —OPO ₃ (R _e ) (R _f ), or —PO ₃ (R _d ) (R _e ). Here, R _a , R _b and R _c each independently represent a hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 8 carbon atoms, R _d is a linear chain having 1 to 8 carbon atoms, Represents a branched or cyclic alkyl group, and R _e and R _f each independently represents a hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 8 carbon atoms, an alkali metal, an alkaline earth metal, or onium. , R _g represents a linear, branched or cyclic alkyl group having 1 to 8 carbon atoms, a halogen atom, an inorganic anion, or an organic anion. _{Further, -CON (R a) (R} b), - OCON (R a) (R b), - NHCON (R a) (R b), - SO 2 N (R a) (R b) -PO 3 (R _e ) (R _f ), -OPO ₃ (R _e ) (R _f ), -PO ₂ (R _d ) (R _e ), -N (R _a ) (R _b ) (R _c ) or -N (R _a ) (R _b ) (R _c ) (R _g ) R _{a to} R _g may be bonded to each other to form a ring, and the formed ring is an oxygen atom, sulfur atom, nitrogen It may be a heterocycle containing a heteroatom such as an atom. R _{a to} R _g may further have a substituent, and the substituent that can be introduced here is the same as the substituent that can be introduced when R ^{1 to} R ⁸ are alkyl groups. Can be listed.

Specific examples of R _a , R _b or R _c include a hydrogen atom, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, isopropyl group, isobutyl group, and s-butyl. Preferred examples include a group, t-butyl group, isopentyl group, neopentyl group, 1-methylbutyl group, isohexyl group, 2-ethylhexyl group, 2-methylhexyl group, cyclopentyl group and the like.
Specific examples of R _d include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, isopropyl, isobutyl, s-butyl, t-butyl, and isopentyl. Preferred examples include a group, neopentyl group, 1-methylbutyl group, isohexyl group, 2-ethylhexyl group, 2-methylhexyl group, cyclopentyl group and the like.
R _e, specifically as R _f, in addition to the alkyl groups mentioned R _a to R _d, a hydrogen atom; lithium, sodium, alkali metals such as potassium, calcium, alkaline earth such as barium metal, or, , Ammonium, iodonium, sulfonium and the like.
Specific examples of R _g include a hydrogen atom; a halogen atom such as a fluorine atom, a chlorine atom, or a bromine atom; a nitrate anion, a sulfate anion, or a tetrafluoroborate anion, in addition to the alkyl group represented by R _{a to} R _d Inorganic anions such as hexafluorophosphate anion, and organic anions such as methanesulfonate anion, trifluoromethanesulfonate anion, nonafluorobutanesulfonate anion, and p-toluenesulfonate anion.
Further, as specifically such ^{_{X, -CO 2 - Na +,}} -CONH 2, -SO 3 - Na +, -SO 2 NH 2, -PO 3 H 2 and the like are preferable.

x and y represent the copolymerization ratio of the structural unit represented by the general formula (IV-a) and the structural unit represented by the general formula (IV-b) in the specific hydrophilic polymer. x and y are 0 <x <100 and 0 <y <100. x: y is preferably in the range of 99: 1 to 10:90, more preferably in the range of 99: 1 to 50:50.
Here, the general formula (IV-a) and the general formula (IV-b), which are structural units constituting the polymer chain, each include the same plural structural units even if they are all the same. In this case, the copolymerization ratio of the structural unit corresponding to the general formula (IV-a) and the structural unit corresponding to the general formula (IV-b) is preferably in the above range.

  The mass average molecular weight of the specific hydrophilic polymer is preferably 1,000 to 1,000,000, more preferably 1,000 to 500,000, and most preferably 1,000 to 200,000.

  Specific examples of the hydrophilic polymer are shown below, but the present invention is not limited thereto. M.M. W. Represents a mass average molecular weight. In addition, the polymer of the specific example shown below means that it is a random copolymer in which each structural unit described is contained by the described molar ratio.

  More preferred are the following hydrophilic polymers.

Each of the compounds for synthesizing the specific hydrophilic polymer of the present invention is commercially available or can be easily synthesized.
Any of the conventionally known methods can be used as the radical polymerization method for synthesizing the specific hydrophilic polymer. Specifically, general radical polymerization methods include, for example, New Polymer Experimental Science 3, Polymer Synthesis and Reaction 1 (Edited by the Society of Polymer Science, Kyoritsu Shuppan), New Experimental Chemistry Course 19, Polymer Chemistry (I) (Edited by Chemical Society of Japan, Maruzen), Materials Engineering Course, Synthetic Polymer Chemistry (Tokyo Denki University Press), etc., and these can be applied.

  The specific hydrophilic polymer may be a copolymer with another monomer as described later. Examples of other monomers used include acrylic esters, methacrylic esters, acrylamides, methacrylamides, vinyl esters, styrenes, acrylic acid, methacrylic acid, acrylonitrile, maleic anhydride, maleic imide, etc. These known monomers are also included. By copolymerizing such monomers, various physical properties such as film forming property, film strength, hydrophilicity, hydrophobicity, solubility, reactivity, and stability can be improved.

  Specific examples of acrylic esters include methyl acrylate, ethyl acrylate, (n- or i-) propyl acrylate, (n-, i-, sec- or t-) butyl acrylate, amyl acrylate, 2-ethylhexyl acrylate, Dodecyl acrylate, chloroethyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxypentyl acrylate, cyclohexyl acrylate, allyl acrylate, trimethylolpropane monoacrylate, pentaerythritol monoacrylate, benzyl acrylate, methoxybenzyl acrylate, chloro Benzyl acrylate, hydroxybenzyl acrylate, hydroxyphenethyl acrylate, dihydroxyphene Chill acrylate, furfuryl acrylate, tetrahydrofurfuryl acrylate, phenyl acrylate, hydroxyphenyl acrylate, chlorophenyl acrylate, sulfamoylphenyl acrylate, 2- (hydroxyphenyl carbonyloxy) ethyl acrylate.

  Specific examples of methacrylic acid esters include methyl methacrylate, ethyl methacrylate, (n- or i-) propyl methacrylate, (n-, i-, sec- or t-) butyl methacrylate, amyl methacrylate, 2-ethylhexyl methacrylate, Dodecyl methacrylate, chloroethyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxypentyl methacrylate, cyclohexyl methacrylate, allyl methacrylate, trimethylolpropane monomethacrylate, pentaerythritol monomethacrylate, benzyl methacrylate, methoxybenzyl methacrylate, chloro Benzyl methacrylate, hydroxybenzyl methacrylate, hydroxy E phenethyl methacrylate, dihydroxyphenethyl methacrylate, furfuryl methacrylate, tetrahydrofurfuryl methacrylate, phenyl methacrylate, hydroxyphenyl methacrylate, chlorophenyl methacrylate, sulfamoylphenyl methacrylate, 2- (hydroxyphenyl carbonyloxy) ethyl methacrylate.

  Specific examples of acrylamides include acrylamide, N-methylacrylamide, N-ethylacrylamide, N-propylacrylamide, N-butylacrylamide, N-benzylacrylamide, N-hydroxyethylacrylamide, N-phenylacrylamide, and N-tolylacrylamide. N- (hydroxyphenyl) acrylamide, N- (sulfamoylphenyl) acrylamide, N- (phenylsulfonyl) acrylamide, N- (tolylsulfonyl) acrylamide, N, N-dimethylacrylamide, N-methyl-N-phenylacrylamide , N-hydroxyethyl-N-methylacrylamide and the like.

  Specific examples of methacrylamides include methacrylamide, N-methylmethacrylamide, N-ethylmethacrylamide, N-propylmethacrylamide, N-butylmethacrylamide, N-benzylmethacrylamide, N-hydroxyethylmethacrylamide, N -Phenylmethacrylamide, N-tolylmethacrylamide, N- (hydroxyphenyl) methacrylamide, N- (sulfamoylphenyl) methacrylamide, N- (phenylsulfonyl) methacrylamide, N- (tolylsulfonyl) methacrylamide, N , N-dimethylmethacrylamide, N-methyl-N-phenylmethacrylamide, N-hydroxyethyl-N-methylmethacrylamide and the like.

Specific examples of vinyl esters include vinyl acetate, vinyl butyrate, vinyl benzoate and the like.
Specific examples of styrenes include styrene, methyl styrene, dimethyl styrene, trimethyl styrene, ethyl styrene, propyl styrene, cyclohexyl styrene, chloromethyl styrene, trifluoromethyl styrene, ethoxymethyl styrene, acetoxymethyl styrene, methoxy styrene, dimethoxy styrene. Chlorostyrene, dichlorostyrene, bromostyrene, iodostyrene, fluorostyrene, carboxystyrene and the like.

  The proportion of these other monomers used in the synthesis of the copolymer must be sufficient to improve various physical properties, but the function as a hydrophilic film is sufficient, and a specific hydrophilic polymer is added. In order to obtain a sufficient advantage, it is preferable that the ratio is not too large. Accordingly, the preferred total proportion of other monomers in the specific hydrophilic polymer is preferably 80% by mass or less, and more preferably 50% by mass or less.

  The specific hydrophilic polymer according to the present invention is preferably contained in the range of 50% by mass or more from the viewpoint of curability and hydrophilicity with respect to the solid content (nonvolatile component) of the hydrophilic composition of the present invention. . Here, the non-volatile component refers to a component excluding a volatile solvent.

  Since the specific hydrophilic polymer according to the present invention has high hydrophilicity, the Rmax of the coating surface can be controlled to a specific value. Without such a hydrophilic polymer, it is considered difficult to control Rmax to a specific value of the present invention when super hydrophilicity is desired.

[Metal alkoxide compound selected from Si, Ti, Zr, and Al]
The metal alkoxide compound used in the present invention is a hydrolyzable polymerizable compound having a functional group capable of being hydrolyzed and polycondensed in its structure and serving as a crosslinking agent, and metal alkoxides are polycondensed with each other. As a result, a strong cross-linked film having a cross-linked structure is formed, and the hydrophilic polymer is also chemically bonded. The metal alkoxide can be represented by general formula (I-1) and general formula (I-2), in which R ⁸ represents a hydrogen atom, an alkyl group or an aryl group, and R ⁹ represents an alkyl group or an aryl group. Z represents Si, Ti or Zr, and m represents an integer of 0-2. The number of carbon atoms when R ⁸ and R ⁹ represent an alkyl group is preferably 1 to 4. The alkyl group or aryl group may have a substituent, and examples of the substituent that can be introduced include a halogen atom, an amino group, and a mercapto group. This compound is a low molecular compound and preferably has a molecular weight of 2000 or less.

_{^{(R 8) m -Z- (OR}} 9) 4-m (I-1)
Al- (OR ⁹ ) ₃ (I-2)

  Specific examples of the hydrolyzable compounds represented by general formula (I-1) and general formula (I-2) are shown below, but the present invention is not limited thereto. When Z is Si, that is, the hydrolyzable compound containing silicon includes, for example, trimethoxysilane, tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, γ- Examples include chloropropyl triethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane, and the like. Among these, particularly preferred are trimethoxysilane, tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane and the like.

When Z is Ti, i.e., including titanium, for example, trimethoxy titanate, tetramethoxy titanate, triethoxy titanate, tetraethoxy titanate, tetrapropoxy titanate, chlorotrimethoxy titanate, chlorotriethoxy titanate, ethyl Examples include trimethoxy titanate, methyl triethoxy titanate, ethyl triethoxy titanate, diethyl diethoxy titanate, phenyl trimethoxy titanate, and phenyl triethoxy titanate.
When Z is Zr, that is, the one containing zirconium can include, for example, zirconates corresponding to the compounds exemplified as those containing titanium.
Further, when the central metal is Al, that is, examples of those containing aluminum in the hydrolyzable compound include trimethoxy aluminate, triethoxy aluminate, tripropoxy aluminate, triisopropoxy aluminate, and the like. be able to.
The content of the metal alkoxide compound selected from Si, Ti, Zr, and Al is preferably 0.1% by mass to 20% by mass with respect to the total solid content of the hydrophilic composition. More preferably, it is 1-10 mass%.

〔catalyst〕
The metal complex catalyst that can be used in the formation of the hydrophilic layer of the present invention promotes hydrolysis and polycondensation of a metal alkoxide compound selected from Si, Ti, Zr, and Al, and causes a bond with a hydrophilic polymer. Can do. Particularly preferred metal complex catalysts include metal elements selected from groups 2A, 3B, 4A and 5A of the periodic table and β-diketones, ketoesters, hydroxycarboxylic acids or esters thereof, amino alcohols, and enolic active hydrogen compounds. It is a metal complex composed of a selected oxo or hydroxy oxygen-containing compound.
Among the constituent metal elements, 2A group elements such as Mg, Ca, Sr and Ba, 3B group elements such as Al and Ga, 4A group elements such as Ti and Zr, and 5A group elements such as Nb and Ta are preferable. Each forms a complex with an excellent catalytic effect. Of these, complexes obtained from Zr, Al and Ti are excellent and preferred.

  In the present invention, the oxo- or hydroxy-oxygen-containing compound constituting the ligand of the metal complex is a β-diketone such as acetylacetone (2,4-pentanedione) or 2,4-heptanedione, methyl acetoacetate, acetoacetic acid Ketoesters such as ethyl and butyl acetoacetate, lactic acid, methyl lactate, salicylic acid, ethyl salicylate, phenyl salicylate, malic acid, tartaric acid, methyl tartrate and other hydroxycarboxylic acids and esters thereof, 4-hydroxy-4-methyl-2-pentanone , 4-hydroxy-2-pentanone, 4-hydroxy-4-methyl-2-heptanone, ketoalcohols such as 4-hydroxy-2-heptanone, monoethanolamine, N, N-dimethylethanolamine, N-methyl- Monoethanolamine, diethanolamine , Amino alcohols such as triethanolamine, methylol melamine, methylol urea, methylol acrylamide, and enol active compounds such as malonic acid diethyl ester, methyl group, methylene group or carbonyl carbon of acetylacetone (2,4-pentanedione) And compounds having a group.

  A preferred ligand is acetylacetone or an acetylacetone derivative. In the present invention, the acetylacetone derivative refers to a compound having a substituent on the methyl group, methylene group or carbonyl carbon of acetylacetone. As the substituents substituted on the methyl group of acetylacetone, all are linear or branched alkyl groups having 1 to 3 carbon atoms, acyl groups, hydroxyalkyl groups, carboxyalkyl groups, alkoxy groups, alkoxyalkyl groups, and acetylacetone As a substituent for the methylene group, a carboxyl group, each of which is a linear or branched carboxyalkyl group and a hydroxyalkyl group having 1 to 3 carbon atoms, and a substituent for the carbonyl carbon of acetylacetone is a carbon number. Is an alkyl group of 1 to 3, and in this case, a hydrogen atom is added to the carbonyl oxygen to form a hydroxyl group.

  Specific examples of preferred acetylacetone derivatives include ethylcarbonylacetone, n-propylcarbonylacetone, i-propylcarbonylacetone, diacetylacetone, 1-acetyl-1-propionyl-acetylacetone, hydroxyethylcarbonylacetone, hydroxypropylcarbonylacetone, acetoacetic acid. , Acetopropionic acid, diacetacetic acid, 3,3-diacetpropionic acid, 4,4-diacetbutyric acid, carboxyethylcarbonylacetone, carboxypropylcarbonylacetone, diacetone alcohol. Of these, acetylacetone and diacetylacetone are particularly preferred. The complex of the above acetylacetone derivative and the above metal element is a mononuclear complex in which one to four molecules of the acetylacetone derivative are coordinated per metal element, and the coordinateable bond of the acetylacetone derivative is a coordinateable bond of the acetylacetone derivative When the number of hands is larger than the total number of hands, ligands commonly used for ordinary complexes such as water molecules, halogen ions, nitro groups, and ammonio groups may coordinate.

  Examples of preferred metal complexes include tris (acetylacetonato) aluminum complex, di (acetylacetonato) aluminum / aco complex, mono (acetylacetonato) aluminum / chloro complex, di (diacetylacetonato) aluminum complex, ethylacetate Acetate aluminum diisopropylate, aluminum tris (ethylacetoacetate), cyclic aluminum oxide isopropylate, tris (acetylacetonato) barium complex, di (acetylacetonato) titanium complex, tris (acetylacetonato) titanium complex, di-i -Propoxy bis (acetylacetonato) titanium complex salt, zirconium tris (ethyl acetoacetate), zirconium tris (benzoic acid) complex salt, etc. are mentioned. These are excellent in stability in aqueous coating solutions and in gelation promotion effect in sol-gel reaction during heat drying, and among them, ethyl acetoacetate aluminum diisopropylate, aluminum tris (ethyl acetoacetate), di ( Acetylacetonato) titanium complex and zirconium tris (ethylacetoacetate) are preferred.

  Although the description of the counter salt of the metal complex described above is omitted in this specification, the type of the counter salt is arbitrary as long as it is a water-soluble salt that maintains the neutrality of the charge as the complex compound, such as nitrate, Salt forms such as halogenates, sulfates, phosphates, etc., that ensure stoichiometric neutrality are used. For the behavior of the metal complex in the silica sol-gel reaction, see J.A. Sol-Gel. Sci. and Tec. There is a detailed description in 16.209 (1999). The following scheme is estimated as the reaction mechanism. That is, in the coating solution, the metal complex has a coordinated structure and is stable, and in the dehydration condensation reaction that starts in the heat drying process after coating, it is considered that crosslinking is promoted by a mechanism similar to an acid catalyst. In any case, the use of this metal complex has led to the improvement of coating solution aging stability and film surface quality, as well as high hydrophilicity and high durability.

In addition to the above-mentioned metal complex catalyst, a catalyst that promotes hydrolysis and polycondensation of a metal alkoxide compound selected from Si, Ti, Zr, and Al and can cause a bond with a hydrophilic polymer is used in combination. May be. Examples of such a catalyst include hydrogen halides such as hydrochloric acid, nitric acid, sulfuric acid, sulfurous acid, hydrogen sulfide, perchloric acid, hydrogen peroxide, carbonic acid, carboxylic acids such as formic acid and acetic acid, and the structural formula represented by RCOOH. Compounds having an acidity such as substituted carboxylic acids in which R is substituted with other elements or substituents, sulfonic acids such as benzenesulfonic acid, etc., or basic compounds such as ammoniacal bases such as aqueous ammonia and amines such as ethylamine and aniline Is mentioned.
The above metal complex catalyst can be easily obtained as a commercial product, and can also be obtained by a known synthesis method, for example, reaction of each metal chloride with an alcohol.
The content of the catalyst is preferably 0.1% by mass to 20% by mass with respect to the total solid content of the hydrophilic composition. More preferably, it is 1-10 mass%.

[Antimicrobial agent]
In order to impart antibacterial, antifungal and antialgal properties to the fin material of the present invention, an antibacterial agent can be contained in the hydrophilic coating solution composition. In the formation of the hydrophilic layer, it is preferable to contain a hydrophilic and water-soluble antibacterial agent. By containing a hydrophilic and water-soluble antibacterial agent, a fin material excellent in antibacterial, antifungal and antialgal properties can be obtained without impairing surface hydrophilicity.
As the antibacterial agent, it is preferable to add a compound that does not reduce the hydrophilicity of the fin material, and examples of such an antibacterial agent include inorganic antibacterial agents and water-soluble organic antibacterial agents. As the antibacterial agent, those exhibiting a bactericidal effect against fungi existing around us, such as bacteria represented by Staphylococcus aureus and Escherichia coli, and fungi such as fungi and yeast are used.

Examples of organic antibacterial agents include phenol ether derivatives, imidazole derivatives, sulfone derivatives, N-haloalkylthio compounds, anilide derivatives, pyrrole derivatives, quaternary ammonium salts, pyridines, triazines, benzoisothiazolines, and isothiazolines. It is done.
For example, 1,2-benzisothiazolin-3-one, N-fluorodichloromethylthio-phthalimide, 2,3,5,6-tetrachloroisophthalonitrile, N-trichloromethylthio-4-cyclohexene-1,2-dicarboxyl Imido, copper 8-quinolinate, bis (tributyltin) oxide, 2- (4-thiazolyl) benzimidazole (hereinafter referred to as TBZ), methyl 2-benzimidazole carbamate (hereinafter referred to as BCM), 10,10 '-Oxybisphenoxyarsine (hereinafter referred to as OBPA) 2,3,5,6-tetrachloro-4- (methylsulfone) pyridine, bis (2-pyridylthio-1-oxide) zinc (hereinafter referred to as ZPT) >, N, N-dimethyl-N ′-(fluorodichloromethylthio) -N′-phenylsulfamide <dichloro Luanide>, poly- (hexamethylene biguanide) hydrochloride, dithio-2-2′-bis (benzmethylamide), 2-methyl-4,5-trimethylene-4-isothiazolin-3-one, 2-bromo-2 -Nitro-1,3-propanediol, hexahydro-1,3-tris- (2-hydroxyethyl) -S-triazine, p-chloro-m-xylenol, 1,2-benzisothiazolin-3-one, etc. However, it is not limited to these.
These organic antibacterial agents can be appropriately selected and used in consideration of hydrophilicity, water resistance, sublimation property, safety and the like. Among organic antibacterial agents, 2-bromo-2-nitro-1,3-propanediol, TBZ, BCM, OBPA, and ZPT are preferable from the viewpoint of hydrophilicity, antibacterial effect, and cost.

  Examples of inorganic antibacterial agents include mercury, silver, copper, zinc, iron, lead, bismuth and the like in descending order of bactericidal action. For example, the thing which carry | supported metals and metal ions, such as silver, copper, zinc, nickel, on the silicate type | system | group support | carrier, phosphate type | system | group support, an oxide, glass, potassium titanate, an amino acid, etc. is mentioned. For example, zeolite antibacterial, calcium silicate antibacterial, zirconium phosphate antibacterial, calcium phosphate antibacterial, zinc oxide antibacterial, soluble glass antibacterial, silica gel antibacterial, activated carbon antibacterial, titanium oxide Antibacterial agent, titania antibacterial agent, organometallic antibacterial agent, ion exchanger ceramic antibacterial agent, layered phosphate-quaternary ammonium salt antibacterial agent, antibacterial stainless steel, etc. Absent.

Natural antibacterial agents include chitosan, a basic polysaccharide obtained by hydrolyzing chitin contained in crabs and shrimp shells.
In the present invention, Nikko's “trade name Holon Killer Bees Sera” made of aminometal in which a metal is compounded on both sides of an amino acid is preferable.
These are not transpirationable, easily interact with the polymer and crosslinker component of the hydrophilic layer, can be stably molecularly dispersed or solid dispersed, the antibacterial agent is easily exposed effectively on the hydrophilic layer surface, and Even if it is splashed with water, it does not elute, can maintain its effect for a long time, and does not affect the human body. Moreover, it can disperse | distribute stably with respect to a hydrophilic layer or a coating liquid, and deterioration of a hydrophilic layer or a coating liquid does not occur.
Among the antibacterial agents, silver-based inorganic antibacterial agents and water-soluble organic antibacterial agents are most preferable because of their great antibacterial effects. In particular, silver zeolite in which silver is supported on zeolite, which is a silicate carrier, antibacterial agent in which silver is supported on silica gel, 2-bromo-2-nitro-1,3-propanediol, TPN, TBZ, BCM, OBPA ZPT is preferred. Particularly preferred commercially available silver zeolite antibacterial agents include “Zeomic” by Shinagawa Fuel, “Sylwell” by Fuji Silysia Chemical, and “Bactenone” by JEOL. In addition, “NOVALON” manufactured by Toa Gosei, in which silver is supported on an inorganic ion exchanger ceramic, “ATOMY BALL” manufactured by Catalytic Chemical Industry, and “Suneyeback P” (San-ai Oil), a triazine antibacterial agent, are also preferable.

  The content of the antibacterial agent is generally 0.001 to 10% by mass with respect to the total solid content of the hydrophilic composition, preferably 0.005 to 5% by mass, and 0.01 to 3% by mass. % Is more preferable, 0.02 to 1.5% by mass is particularly preferable, and 0.05 to 1% by mass is most preferable. If the content is 0.001% by mass or more, an effective antibacterial effect can be obtained. Further, if the content is 10% by mass or less, the hydrophilicity is not lowered, the aging is not deteriorated, and the antifouling property and the antifogging property are not adversely affected.

[Inorganic fine particles]
The hydrophilic layer of the present invention may contain inorganic fine particles in order to improve hydrophilicity, prevent cracking of the film, and improve film strength. As the inorganic fine particles, for example, silica, alumina, magnesium oxide, titanium oxide, magnesium carbonate, calcium alginate or a mixture thereof can be preferably mentioned.
The inorganic fine particles preferably have an average particle size of 5 nm to 10 μm, and more preferably 0.5 to 3 μm. Within the above range, it is possible to form a fin material that is stably dispersed in the hydrophilic layer, sufficiently retains the film strength of the hydrophilic layer, and has high durability and excellent hydrophilicity.
Among the inorganic fine particles as described above, a colloidal silica dispersion is particularly preferable and can be easily obtained as a commercial product.
The content of the inorganic fine particles is preferably 80% by mass or less, and more preferably 50% by mass or less, based on the total solid content of the hydrophilic layer.

[Other ingredients]
Hereinafter, various additives that can be used in the coating liquid for forming the hydrophilic layer of the fin material of the present invention as necessary are described.
1) Surfactant You may add surfactant to the coating liquid for hydrophilic layer formation of the fin material of this invention.
Examples of the surfactant include those described in JP-A Nos. 62-173463 and 62-183457. For example, anionic surfactants such as dialkylsulfosuccinates, alkylnaphthalenesulfonates, fatty acid salts, polyoxyethylene alkyl ethers, polyoxyethylene alkyl allyl ethers, acetylene glycols, polyoxyethylene / polyoxypropylene blocks Nonionic surfactants such as copolymers, and cationic surfactants such as alkylamine salts and quaternary ammonium salts. An organic fluoro compound may be used in place of the surfactant. The organic fluoro compound is preferably hydrophobic. Examples of the organic fluoro compounds include fluorine surfactants, oily fluorine compounds (eg, fluorine oil) and solid fluorine compound resins (eg, tetrafluoroethylene resin). No. (columns 8 to 17) and those described in JP-A Nos. 62-135826.

By using the surfactant and the hydrophilic polymer of the present invention in combination, a higher hydrophilic surface can be formed. Although the mechanism has not been fully elucidated, this is because the hydrophilic segment in the polymer segment is a surfactant due to the action of the surfactant, which is a low molecular weight compound, migrating to the surface of the coating as the coating dries. It is presumed that high hydrophilicity was obtained by being attracted to the hydrophilic part.
In addition, when combined with an antibacterial agent, which is generally a relatively low molecular weight compound, it migrates together with the above-mentioned surfactant, so that it has an effect of effectively imparting an antibacterial effect to the surface without significantly reducing hydrophilicity. it is conceivable that.

2) Ultraviolet Absorber In the present invention, an ultraviolet absorber can be used from the viewpoint of improving the weather resistance and durability of the fin material.
Examples of the ultraviolet absorber are described in JP-A-58-185679, JP-A-61-190537, JP-A-2-782, JP-A-5-97075, JP-A-9-34057, and the like. Bezotriazole compounds, benzophenone compounds described in JP-A-46-2784, JP-A-5-194443, US Pat. No. 3,214,463, etc., JP-B-48-30492, JP-A-56-21141 Cinnamic acid compounds described in JP-A-10-88106, JP-A-4-298503, JP-A-8-53427, JP-A-8-239368, JP-A-10-182621, Special Tables The triazine compounds described in JP-A-8-501291, Research Disclosure No. Examples thereof include compounds described in No. 24239, compounds that emit ultraviolet light by absorbing ultraviolet rays typified by stilbene and benzoxazole compounds, so-called fluorescent brighteners, and the like.
The addition amount is appropriately selected according to the purpose, but generally it is preferably 0.5 to 15% by mass in terms of solid content.

3) Antioxidant In order to improve the stability of the fin material of the present invention, an antioxidant can be added to the coating solution for forming the hydrophilic layer. Examples of the antioxidant include European published patents, 223739, 309401, 309402, 310551, 310552, 359416, and 3435443. No. 5, JP-A-54-262447, JP-A-63-113536, JP-A-63-163351, JP-A-2-262654, JP-A-2-71262, JP-A-3-121449, Examples thereof include those described in JP-A-5-61166, JP-A-5-119449, US Pat. No. 4,814,262, US Pat. No. 4,980,275, and the like.
Although the addition amount is appropriately selected according to the purpose, it is preferably 0.1 to 8% by mass in terms of solid content.

4) Solvent When forming the hydrophilic layer of the fin material of the present invention, it is also effective to add an appropriate organic solvent to the hydrophilic layer forming coating solution in order to ensure the formation of a uniform coating film on the substrate. .
Examples of the solvent include ketone solvents such as acetone, methyl ethyl ketone, and diethyl ketone, alcohol solvents such as methanol, ethanol, 2-propanol, 1-propanol, 1-butanol, and tert-butanol, and chlorine such as chloroform and methylene chloride. Solvents, aromatic solvents such as benzene and toluene, ester solvents such as ethyl acetate, butyl acetate and isopropyl acetate, ether solvents such as diethyl ether, tetrahydrofuran and dioxane, glycols such as ethylene glycol monomethyl ether and ethylene glycol dimethyl ether And ether solvents.
In this case, it is effective to add in a range that does not cause a problem due to the relationship of OC (volatile organic solvent), and the amount is preferably 0 to 50% by mass, more preferably based on the entire coating liquid at the time of fin material formation. It is the range of 0-30 mass%.

5) Polymer compound Various polymer compounds can be added to the coating liquid for forming a hydrophilic layer of the fin material of the present invention in order to adjust the film physical properties of the hydrophilic layer as long as the hydrophilicity is not inhibited. High molecular compounds include acrylic polymer, polyvinyl alcohol resin, polyvinyl butyral resin, polyurethane resin, polyamide resin, polyester resin, epoxy resin, phenol resin, polycarbonate resin, polyvinyl formal resin, shellac, vinyl resin, acrylic resin. Rubber resins, waxes and other natural resins can be used. Two or more of these may be used in combination. Of these, vinyl copolymer obtained by copolymerization of acrylic monomers is preferred. Furthermore, a copolymer containing “carboxyl group-containing monomer”, “methacrylic acid alkyl ester”, or “acrylic acid alkyl ester” as a structural unit is also preferably used as the copolymer composition of the polymer binder.

In addition to this, if necessary, for example, leveling additives, matting agents, waxes for adjusting film physical properties, tackifiers, etc. within a range that does not impair hydrophilicity in order to improve adhesion to the substrate, etc. Can be contained.
As the tackifier, specifically, a high molecular weight adhesive polymer described in JP-A-2001-49200, 5-6p (for example, (meth) acrylic acid and an alkyl group having 1 to 20 carbon atoms). An ester with an alcohol having, an ester of (meth) acrylic acid with an alicyclic alcohol having 3 to 14 carbon atoms, a copolymer comprising an ester of (meth) acrylic acid with an aromatic alcohol having 6 to 14 carbon atoms) And a low molecular weight tackifying resin having a polymerizable unsaturated bond.

  In the fin material of the present invention, the thickness of the coating (hydrophilic film) is preferably 0.1 μm to 10 μm, and more preferably 0.5 μm to 2.0 μm. When the film thickness is 0.1 μm or more, a sufficient hydrophilic effect can be obtained. Further, when the thickness is 10 μm or less, defects such as drying unevenness do not occur.

[Base material]
The fin material of the present invention can be obtained by applying a coating solution for forming a hydrophilic layer on a suitable substrate, heating and drying to form a surface hydrophilic layer. The substrate is preferably a metal substrate or a plastic substrate. Examples of suitable metal substrates include aluminum, zinc, copper, nickel, stainless steel plate (SUS), and the like. Among these, an aluminum substrate is particularly preferable. The plastic substrate used in the present invention is not particularly limited, but polyester, polyethylene, polypropylene, cellophane, triacetyl cellulose, diacetyl cellulose, acetyl cellulose butyrate, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, ethylene vinyl alcohol, Examples thereof include polystyrene, polycarbonate (PC), polymethylpentene, polysulfone, polyether ketone, acrylic, nylon, fluororesin, polyimide, polyetherimide, polyether sulfone, and polymethyl methacrylate (PMMA). Among these, plastic substrates such as polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate, cellulose resins such as polycarbonate, triacetyl cellulose, and diacetyl cellulose are particularly preferable. The heating temperature and heating time for forming the hydrophilic layer are not particularly limited as long as the solvent and the time in which the solvent in the sol solution can be removed and a strong film can be formed. It is preferably 150 ° C. or lower, and the heating time is preferably within 1 hour.
The fin material of the present invention can be prepared by a known coating method, and is not particularly limited. For example, a spray coating method, a dip coating method, a flow coating method, a spin coating method, a roll coating method, a film applicator method, Methods such as screen printing, bar coater, brush coating, and sponge coating can be applied.

  The drying temperature of the coating solution is preferably 10 ° C to 150 ° C, more preferably 25 ° C to 100 ° C. When the drying temperature is low, sufficient crosslinking reaction does not proceed and the coating strength is low. If the temperature is high, the coating film tends to crack, and the antifogging property is partially insufficient. The drying time is preferably 5 minutes to 1 hour. More preferably, it is 10 minutes to 30 minutes. If the drying time is short, the coating strength may decrease due to insufficient drying. If the drying time is excessively longer than necessary, the substrate may deteriorate.

In the present invention, the maximum height Rmax of the protrusions on the surface of the hydrophilic layer is 0.1 μm to 2 μm. Preferably they are 0.5 micrometer-1.5 micrometers. By being in this range, there is an effect of maintaining sufficient hydrophilicity and heat exchange efficiency. If a large protrusion is present even partially on the substrate, the hydrophilic layer may not be sufficiently formed only on that portion, and the protrusion on the substrate is likely to be exposed and the hydrophilicity may not be exhibited. Even if a hydrophilic layer can be formed, in the case of an aluminum fin material, the fins may partially contact each other between the fins, and a sufficient heat exchange rate may not be obtained. On the other hand, if Rmax is too low, the hydrophilic layer may not be applied because it is too smooth and difficult to handle in the coating process.
Further, the center average roughness Ra is preferably 10 nm to 100 nm.
Further, the Tg of the hydrophilic coating is preferably 40 ° C. to 150 ° C. for the purpose of providing heat resistance due to heat generation in the heat exchanger. The elastic modulus of the hydrophilic coating is preferably 1 GPa to 7 GPa.
The method for controlling the surface property of the hydrophilic layer described above controls the particle size and content of the inorganic fine particles used; adjusts the surface roughness of the substrate itself; The viscosity, the heating temperature of the hydrophilic coating, the speed, etc. are controlled, but the present invention is not limited to this.

  Moreover, in this invention, you may provide an intermediate | middle layer between a base material and a hydrophilic layer for the purpose of improving corrosion resistance, adhesiveness with a base material, etc. as needed. The intermediate layer is not particularly limited. Hydrophilic layers having different compositions may be provided, or a known anticorrosion layer represented by a chromate system may be provided.

  In the present invention, the hydrophilic layer has a water contact angle of 15 ° or less, preferably 10 ° or less, both before and after being immersed in water at 30 ° C. for 500 hours. Therefore, it can be said that the fin material of the present invention has sufficient hydrophilicity and the effect can be maintained for a sufficiently long time.

The degree of hydrophilicity of the hydrophilic layer surface can also be evaluated in the measurement of surface free energy. In the present invention, the surface free energy was measured using the Zisman plot method. Specifically, using the property that an aqueous solution of an inorganic electrolyte such as magnesium chloride increases in surface tension with the concentration, after measuring the contact angle in the air at room temperature using the aqueous solution, the horizontal axis indicates the surface of the aqueous solution. Take the value obtained by converting the contact angle into cos θ on the vertical axis and plot the points of aqueous solutions of various concentrations to obtain a linear relationship, and the surface tension when cos θ = 1, that is, the contact angle = 0 °, It is a measurement method defined as the surface free energy of a solid. The surface tension of water is 72 mN / m, and the higher the surface free energy value, the higher the hydrophilicity.
A hydrophilic layer whose surface free energy measured by such a method is in the range of 70 mN / m to 95 mN / m, preferably 72 mN / m to 93 mN / m, more preferably 75 mN / m to 90 mN / m is hydrophilic. Excellent performance and good performance.

  EXAMPLES Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited thereto. In addition, with a part means a mass part.

[Example 1]
400 parts of distilled water and 70 parts of ethanol were added to the hydrophilic polymer and metal alkoxide compound described in Table 1 below, and the mixture was stirred at 25 ° C. for 30 minutes to obtain a hydrophilic composition.
Next, the aluminum plate (A1050 plate thickness 0.1 mm, maximum protrusion height 0.9 μm) was immersed in an alkaline cleaning solution (Yokomi Yushi Semi Clean A-1 diluted in 3% aqueous solution) for 5 minutes, and then washed with water. Degreasing treatment was performed.
The above hydrophilic composition was applied to the degreased aluminum plate surface so that the thickness after drying was 1 μm, and dried by heating at 100 ° C. for 10 minutes.
The obtained fin material of the present invention was evaluated by the following method.

Evaluation method / surface Rmax
The maximum protrusion height in a range in which an area of 100 μm square was measured by a light interference method using a digital optical profilometer (manufactured by WYKO) under the condition of a cut-off of 0.25 mm was defined as Rmax.
-Water immersion After immersing in tap water temperature-controlled at 30 degreeC for 500 hours, it was dried at 90 degreeC for 5 minutes.
-Water drop contact angle The contact angle of the hydrophilic layer surface was calculated | required using ultra pure water using Kyowa Interface Science Co., Ltd. contact angle meter DropMaster500. The contact angle was evaluated before and after the water immersion.
-Crack resistance With respect to the obtained fin material, a hole was made using a punch for office equipment, and an edge portion of the hole was observed at 2000 times using a scanning electron microscope and evaluated according to the following rank.
Excellent: No cracking.
Good: Cracks are generated, but the crack is the longest but less than 20 μm.
Defect: A crack occurs and there is a crack of 20 μm or more.
The results are shown in Table 1.

[Examples 2 to 18 and Comparative Examples 1 to 12]
The same procedure as in Example 1 was conducted except that the substrates having different roughness, hydrophilic polymer, metal alkoxide, and other components were changed to those shown in Table 1 below.

A method for synthesizing Compound A and Compound B, which are hydrophilic polymers, will be described. Other hydrophilic polymers can be synthesized similarly.
Compound A
To a three-necked flask, 100 parts of acrylamide, 10 parts of 3-mercaptopropyltrimethoxysilane, and 200 parts of dimethylacetamide were added and heated and mixed at 80 ° C. under a nitrogen stream. Subsequently, 0.1 part of 2,2′azobis (2,4dimethylvaleronitrile) was added and the reaction was carried out for 5 hours. The obtained reaction liquid was dripped in 3000 L of methanol, and the solid substance was deposited.
The solid matter was taken out by filtration and then dried at 60 ° C. for 12 hours to obtain Compound A.
The molecular weight of the obtained compound A was measured by GPC and determined from the standard polystyrene equivalent value.

Compound B
100 parts of acrylamide, 20 parts of acrylamide-propyltriethoxysilane, and 500 parts of dimethylformamide were added to a three-necked flask and mixed at 80 ° C. under a nitrogen stream.
Subsequently, 0.1 part of 2,2′azobis (2,4dimethylvaleronitrile) was added and the reaction was carried out for 5 hours. The obtained reaction solution was dropped into 3000 L of n-hexane to precipitate a solid.
The solid matter was taken out by filtration and then dried at 60 ° C. for 12 hours to obtain Compound B.
The molecular weight of the obtained compound B was measured by GPC and obtained from the standard polystyrene equivalent value.

  In addition, content of the hydrophilic polymer of Table 1, and a metal alkoxide is a value with respect to the total solid of a hydrophilic composition. Each component and base material used in Examples and Comparative Examples are shown below.

The colloidal silica used was SNO-TEX made by Nissan Chemical.
A commercially available reagent was used as the metal alkoxide.
The following materials were used.
Aluminum: JIS A1050 aluminum alloy plate thickness 150μm
PC: Sumitomo Bakelite Polycaace 6mm thickness PMMA: Mitsubishi Rayon Acrylite 6mm thickness PET: Toyobo Cosmo Shaon A4300 100μm thickness SUS: SUS430 5mm thickness

Claims (6)

  A fin material in which a hydrophilic composition is coated on a substrate, and the coating surface has a maximum height Rmax of a protrusion of 0.1 μm to 2 μm, and was immersed before and after being immersed in water at 30 ° C. for 500 hours. A fin material having a contact angle with water of 15 ° or less in any of the latter.   The fin material according to claim 1, wherein the hydrophilic composition contains 50% by mass or more of a hydrophilic polymer as a solid content.   The fin material according to claim 1, wherein the base material is made of aluminum. The hydrophilic polymer has at least one of a structure represented by the following general formula (IV-a) and a structure represented by the general formula (IV-b). 4. The fin material according to any one of 3.

In general formulas (IV-a) and (IV-b), R ^{1 to} R ⁸ each independently represents a hydrogen atom or a hydrocarbon group having 8 or less carbon atoms. L ¹ represents a single bond or a polyvalent organic linking group. L ² represents a polyvalent organic linking group having one or more structures selected from the group consisting of a single bond, —CONH—, —NHCONH—, —OCONH—, —SO ₂ NH—, and —SO ₃ —. . m represents an integer of 1 to 3. x and y represent composition ratios, and 0 <x <100 and 0 <y <100. X represents —OH, —OR _a , —COR _a , —CO ₂ R _e , —CON (R _a ) (R _b ), —N (R _a ) (R _b ), —NHCOR _d , —NHCO ₂ R _a , —OCON (R _a ) (R _b ), —NHCON (R _a ) (R _b ), —SO ₃ R _e , —OSO ₃ R _e , —SO ₂ R _d , —NHSO ₂ R _d , —SO ₂ N (R _a ) (R _b ), —N (R _a ) (R _b ) (R _c ), —N (R _a ) (R _b ) (R _c ) (R _g ), —PO ₃ (R _e) ) (R _f ), —OPO ₃ (R _e ) (R _f ), or —PO ₃ (R _d ) (R _e ). Here, R _a , R _b and R _c each independently represent a hydrogen atom or a linear, branched or cyclic alkyl group, R _d represents a linear, branched or cyclic alkyl group, R _e and R _f independently represents a hydrogen atom or a linear, branched or cyclic alkyl group, an alkali metal, an alkaline earth metal, or onium, and R _g represents a linear, branched or cyclic alkyl group, a halogen atom, An inorganic anion or an organic anion is represented. )   The fin material according to claim 1, wherein the hydrophilic composition contains an alkoxide compound including any element selected from Si, Ti, Zr, and Al.   It consists of the fin material in any one of Claims 1-5, The fin material for heat exchangers characterized by the above-mentioned.