JP2014105879A - Heat-exchanger aluminum fin material, heat-exchanger aluminum fin material manufacturing method, and heat exchanger comprising the heat-exchanger aluminum fin material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat-exchanger aluminum fin material having a high surface hydrophilic property, suppressing condensation of dew condensation water, suppressing machining failure and cutting failure during pressing, and suppressing drying failure of press oil.SOLUTION: An aluminum fin material comprising a hydrophilic coating film containing 0.01 to 0.1 g/mof a polymer compound mainly consisting of polyoxyethylene chain, and formed on a surface of an aluminum or aluminum alloy plate material, a dynamic friction coefficient of the surface being 0.1 to 0.2, the hydrophilic coating film being formed by applying a coating material containing the polymer compound mainly consisting of polyoxyethylene chain, baking the coating material, and then washing the coating material with water.

Description

  The present invention relates to an aluminum fin material for a heat exchanger, a manufacturing method thereof, and a heat exchanger provided with the aluminum fin material for a heat exchanger.

  In the air conditioner, when the heat exchanger is used on the cooling side, water may aggregate to form water droplets (condensed water), and a water bridge may be formed between adjacent fins. When such a phenomenon occurs, the air passage becomes narrower, the ventilation resistance increases, and the heat exchange efficiency decreases. For this reason, a technique is known in which water droplets such as condensed water are quickly discharged by applying a treatment for imparting wettability (hydrophilicity) to the surface of the heat exchanger fin.

Technologies for imparting hydrophilicity to the surface of fins for heat exchangers include surface treatment of the aluminum fin material surface with an organic polymer resin solution containing porous silica fine particles, and organic polymer substances composed of acrylic resins. There is known a technique for coating an aluminum fin material with a film formed by mixing, applying, and drying an aqueous composition containing SiO _{2 and} TiO ₂ .
However, in the technique of forming a film by applying a composition containing inorganic oxide powder such as silica as described above, since the hardness of the inorganic oxide powder particles is high, an aluminum plate is formed into a fin material. There is a drawback that the mold is easily worn during processing.

Therefore, in recent years, a method of forming a hydrophilic film by applying a treatment agent combining a plurality of hydrophilic polymers on the surface of an aluminum fin material without using the above-described inorganic oxide powder has been widely used. It has been broken. This hydrophilic film is often formed from a treatment agent containing a compound containing a polyoxyethylene chain such as polyethylene glycol or polyethylene oxide together with an acrylic resin containing polyacrylic acid, polyvinyl alcohol, or the like (Patent Document 1). To 3).
By containing a compound containing a polyoxyethylene chain, it has the effect of accelerating the curing reaction of the coating film and improving the adhesion, and further imparting lubricity to the coating film after baking, There are effects such as prevention of seizure, suppression of mold wear, and smooth material feeding in the mold.

Japanese Patent Laid-Open No. 8-200903 JP-A-8-261688 JP 2004-331893 A

For imparting surface lubricity, a method of forming a film by mixing a polymer compound containing a polyoxyethylene chain such as polyethylene glycol or polyethylene oxide with an acrylic resin or polyvinyl alcohol containing polyacrylic acid as a main component; A method of further forming a film containing a polymer compound mainly composed of a polyoxyethylene chain such as polyethylene glycol or polyethylene oxide after forming a film composed of an acrylic resin mainly composed of polyacrylic acid, polyvinyl alcohol or the like There is.
However, when pressing a material with the above-described treatment agent, the coefficient of friction becomes too low, so that the material feed in the mold becomes unstable due to excessive sliding of the surface or transfer of the lubricating component to the mold. Therefore, there is a problem that cutting failure occurs.
The present invention has been made to solve these problems, has high hydrophilicity, can suppress the condensation of condensed water, and has an appropriate lubricity and is processed during press processing of an aluminum fin material. The purpose is to suppress defects and cutting defects.

The present invention relates to the following.
(1) A hydrophilic coating containing 0.01 to 0.1 g / m ^{2 of} a polymer compound mainly composed of a polyoxyethylene chain is formed on the surface of a plate made of aluminum or an aluminum alloy, and the surface dynamic friction An aluminum fin material having a coefficient of 0.1 to 0.2, wherein the hydrophilic film is coated with a coating containing a polymer compound mainly composed of polyoxyethylene chains and baked. An aluminum fin material for a heat exchanger, which is formed by washing with water.
(2) In the aluminum fin material for a heat exchanger according to (1), the polymer compound mainly composed of polyoxyethylene chains contained in the hydrophilic coating is 50 to 5500 mPa · S in a 5% aqueous solution at 25 ° C. An aluminum fin material for heat exchangers, characterized in that
(3) An aluminum fin material for a heat exchanger according to (1) or (2), wherein the baking is performed at a plate reaching temperature of 120 ° C to 250 ° C.
(4) A heat exchanger comprising a plurality of the aluminum fin materials for a heat exchanger according to any one of (1) to (3).
(5) The surface of the plate made of aluminum or aluminum alloy is coated with a paint containing a polymer compound mainly composed of polyoxyethylene chains, baked and then washed with water to thereby remove polyoxyethylene chains. A method for producing an aluminum fin material for a heat exchanger, comprising forming a hydrophilic film having a residual amount of a polymer compound as a main component of 0.01 to 0.1 g / m ² .
(6) In the method for producing an aluminum fin material for a heat exchanger according to (5), the polymer compound having a polyoxyethylene chain as a main component has a viscosity of 50 to 5500 mPa · S in a 5% aqueous solution at 25 ° C. What is claimed is: 1. A method for producing an aluminum fin material for a heat exchanger, wherein:
(7) In the method for producing an aluminum fin material for a heat exchanger according to (5) or (6), the baking is performed at a plate arrival temperature of 120 ° C to 250 ° C. Production method.

The aluminum fin material for a heat exchanger of the present invention has a hydrophilic film containing 0.01 to 0.1 g / m ^{2 of} a polymer compound having a polyoxyethylene chain as a main component on the surface of a plate made of aluminum or an aluminum alloy. Is formed. Thereby, moderate lubricity with a dynamic friction coefficient of 0.1 to 0.2 on the surface is imparted, and seizure to the mold, wear of the mold, and cutting failure during press working can be suppressed.

It is a perspective view which shows an example of the aluminum fin material for heat exchangers which concerns on this invention. It is a fragmentary sectional view of the aluminum fin material shown in FIG. It is a perspective view which shows an example of the heat exchanger provided with two or more aluminum fin materials shown in FIG.

Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings.
1 is a perspective view showing an example of an aluminum fin material for a heat exchanger according to the present invention, FIG. 2 is a partial sectional view of the aluminum fin material, and FIG. 3 shows an example of a heat exchanger provided with the aluminum fin material. It is a perspective view. The aluminum fin material 10 of the present embodiment has an elongated strip shape, and the collars 11 through which the heat transfer tubes 30 (see FIG. 3) made of copper or aluminum alloy pass are arranged in a single row or multiple rows in the length direction. Arranged at intervals. A slit 12 is provided on the surface of the aluminum fin material 10 for the purpose of improving heat transfer performance.

As shown in FIG. 2, an aluminum fin material 10 shown in FIG. 1 is formed by forming a hydrophilic coating 14 on the surface of a fin plate 13 made of aluminum or an aluminum alloy.
The aluminum or aluminum alloy is not particularly limited, and an aluminum material having a composition generally applied to a base material for a heat exchanger may be appropriately used. In addition, if illustrated, JIS regulation A1050, A1200 material, etc. are mentioned.
As the fin plate 13, an aluminum or aluminum alloy plate subjected to a surface treatment such as a phosphoric acid chromate treatment is preferably used. The shape of the board | plate material 13 is not specifically limited, According to the form of the heat exchanger to which the aluminum fin material 10 is applied, it selects suitably.

The hydrophilic coating 14 is formed using a paint containing a polymer compound containing a polyoxyethylene chain. Examples of the polymer compound containing a polyoxyethylene chain include polyethylene glycol and polyethylene oxide.
The coating for forming the hydrophilic coating 14 contains a polymer compound mainly composed of a polyoxyethylene chain, thereby promoting a baking reaction (coating reaction of the coating) during the formation of the hydrophilic coating 14. Thus, the adhesion of the hydrophilic coating 14 to the plate 13 can be improved.
Further, when the coating material for forming the hydrophilic film 14 contains a polymer compound mainly composed of polyoxyethylene chains, the polymer compound containing polyoxyethylene chains remains in the hydrophilic film 14 to be formed. It will be. As a result, lubricity is imparted to the surface of the aluminum fin material 10, and it is possible to prevent seizure on the mold during pressing, and to achieve effects such as smooth feeding of the material.

However, in the press working of the aluminum fin material 10, if the friction coefficient of the aluminum fin material 10 becomes too low due to the lubricating effect of the hydrophilic coating 14 described above, the mold is caused by slipping of the surface or transfer of the lubricating component to the mold. There is a possibility that the material feed becomes unstable and a cutting failure occurs.
Therefore, in the present invention, the polyoxyethylene chain of the hydrophilic coating 14 is formed as a main component by applying a paint containing a polymer compound having a polyoxyethylene chain as a main component, followed by baking and washing with water. The content of the polymer compound is 0.01 g / m ² or more and 0.1 g / m ² or less. Thereby, the dynamic friction coefficient of the plate surface can be 0.1 or more and 0.2 or less, and while preventing the seizure to the mold at the time of press working, suppressing excessive slip of the material due to imparting lubricity, Cutting failure can be prevented.

In the present invention, as the polymer compound containing a polyoxyethylene chain, a polymer compound having a viscosity of 50 mPa · S or more and 5500 mPa · S or less in a 5% aqueous solution at 25 ° C. is used.
When a polymer compound containing a polyoxyethylene chain having a viscosity of less than 50 mPa · S is used in a 5% aqueous solution at 25 ° C., the polymer compound containing the polyoxyethylene chain is excessively washed off by washing with water after baking. Therefore, the amount (content) of the polymer compound containing the polyoxyethylene chain as the main component contained in the hydrophilic coating 14 is less than 0.01 g / m ² . That is, sufficient lubricity (dynamic friction coefficient 0.1 or more) cannot be obtained. Depending on the conditions of water washing, that is, by shortening the water washing time, the coefficient of dynamic friction can be made 0.1 or more, but in a 5% aqueous solution at 25 ° C., the polyoxyethylene chain having a viscosity of less than 50 mPa · S When a polymer compound containing is used, the coating itself is soft, so that it can be easily transferred to a mold, and a cutting failure is likely to occur when press processing is continuously performed.
When the viscosity is 50 mPa · S or more in a 5% aqueous solution at 25 ° C., transfer to a mold can be suppressed, and deterioration of lubricity can be reduced. For this reason, processing defects such as seizure to the mold can be effectively suppressed, and good press workability can be obtained.

Further, in a 5% aqueous solution at 25 ° C., when the viscosity exceeds 5500 mPa · S, stringing occurs at the time of coating, and coating becomes difficult. Application can be made possible by reducing the amount added, but due to the high viscosity, it is difficult to remove by washing with water, and the content of the polymer compound mainly composed of polyoxyethylene chains is 0.1 g / m. It will exceed ² . That is, the dynamic friction coefficient cannot be made 0.1 or more, and the surface tends to slip excessively, so that a cutting failure is likely to occur during press working.

The viscosity of a polymer compound containing a polyoxyethylene chain in a 5% aqueous solution at 25 ° C. has a correlation with the viscosity average molecular weight. That is, when a material having a large viscosity average molecular weight is used, the viscosity is increased, and when a material having a small viscosity is used, the viscosity is decreased. Accordingly, the polymer compound containing a polyoxyethylene chain is selected to have an appropriate viscosity average molecular weight in which a viscosity is 50 mPa · S to 5500 mPa · S in a 5% aqueous solution at 25 ° C.
Moreover, you may use the high molecular compound containing a polyoxyethylene chain in mixture of 2 or more types from which molecular weight differs.

The coating material for forming the hydrophilic coating 14 is not particularly limited as long as it contains a polymer compound mainly composed of a polyoxyethylene chain. It is preferable to contain a hydrophilic resin.
The coating material for forming the hydrophilic coating 14 preferably contains 10 to 40 parts by weight of a polymer compound having a polyoxyethylene chain as a main component with respect to 100 parts by weight of the total solid content in the coating material. By setting the content of the polymer compound having a polyoxyethylene chain as a main component in the above range, the curing reaction of the coating film during baking is sufficiently promoted and the adhesion of the formed hydrophilic coating 14 is enhanced. be able to.

Examples of other hydrophilic resins that may be contained in the coating material for forming the hydrophilic coating 14 include resins having a hydrophilic functional group such as a hydroxyl group, a carboxyl group, and an ether group (provided that the polyoxyethylene chain is included). Excluding high molecular compounds as the main component).
Specific examples of the other hydrophilic resin include, for example, a polymer compound obtained by polymerizing a monomer having a polyoxyalkylene chain and a polymerizable double bond as essential components, an acrylic resin mainly composed of polyacrylic acid, and a polyvinyl alcohol type. Resin, cellulose resin, etc. are mentioned, These 1 type (s) or 2 or more types can be used in combination.

  When the coating for forming the hydrophilic coating 14 contains an acrylic resin mainly composed of polyacrylic acid as the other hydrophilic resin, the content is not particularly limited and can be appropriately adjusted. It is desirable that the content of the high molecular compound containing as a main component satisfies the above-described preferable range.

  Examples of acrylic resins mainly composed of polyacrylic acid include acrylic acid homopolymer, acrylic acid and methacrylic acid, methyl acrylate, acrylamide, polyacrylic acid copolymer, 2-hydroxyethyl methacrylate, acrylonitrile, acrylamide Examples include copolymers of various acrylic monomers such as copolymers, and two or more of these may be used.

When the coating material for forming the hydrophilic coating 14 contains a polyvinyl alcohol resin as another hydrophilic resin, it contains 0 to 40 parts by weight of the polyvinyl alcohol resin with respect to 100 parts by weight of the total solid content in the paint. Is preferred.
One type of polyvinyl alcohol resin may be used, or two or more types may be used.

When the coating material for forming the hydrophilic coating 14 contains a cellulose resin as another hydrophilic resin, it is preferable to contain 0 to 40 parts by weight of the cellulose resin with respect to 100 parts by weight of the total solid content in the coating material. When content of a cellulose resin exceeds 40 weight part, the adhesiveness of the hydrophilic coating 14 may fall.
Examples of the cellulose resin include sodium carboxymethyl cellulose, hydroxymethyl cellulose, hydroxypropyl cellulose, methyl cellulose, and the like, and two or more of these may be used.

By blending and mixing a polymer compound having a polyoxyethylene chain as a main component with the above composition and, if necessary, other hydrophilic resin, a high molecular weight having a polyoxyethylene chain as a main component. A coating containing a molecular compound is prepared, and this coating is applied to the surface of the plate 13 using a coating device to form a coating. After baking this coating, the polyoxyethylene chain is washed with water. A hydrophilic film 14 containing 0.01 to 0.1 g / m ^{2 of} a polymer compound as a main component can be obtained. In addition, the coating material may contain water or a solvent containing water as a main component as necessary.

The coating is usually applied using a coating device such as a roll coater so as to obtain an appropriate film thickness.
The thickness of the coating film forming the hydrophilic coating film 14 is not particularly limited, but the coating film should have a thickness of 0.4 μm or more and 3 μm or less obtained by baking and washing with water. Is desirable.
When the thickness of the hydrophilic coating 14 is increased, the heat transfer tube 30 and the fin plate 13 are connected via the relatively thick hydrophilic coating 14 when the aluminum fin material 10 is incorporated in the heat exchanger 20. The heat transfer resistance may increase. Accordingly, the coating film is formed so that the thickness of the hydrophilic coating film 14 is 3 μm or less, thereby suppressing an increase in heat transfer resistance between the heat transfer tube 30 and the aluminum fin material 10.
If the hydrophilic coating 14 is too thin, the effect of providing the hydrophilic coating 14 may not be sufficiently obtained. From the above viewpoint, the thickness of the hydrophilic coating 14 is desirably set to about the lower limit of the thickness range in which necessary hydrophilicity can be obtained, and specifically, it is preferably set to 0.4 μm or more.

The baking process of the coating film can be performed by holding at a plate arrival temperature of 120 ° C. or higher and 250 ° C. or lower for 5 seconds or more in a heating furnace such as a normal hot air oven.
If the plate arrival temperature is less than 120 ° C., the hydrophilicity of the aluminum fin material 10 becomes poor, and water droplets such as condensed water cannot be discharged quickly. Furthermore, the adhesion of the hydrophilic coating 14 to the plate material 13 is deteriorated, and in addition, the lubricity of the surface of the aluminum fin material 10 becomes too high, which may cause cutting failure.
If the plate arrival temperature exceeds 250 ° C., the hydrophilicity of the aluminum fin material 10 becomes poor. In addition, the lubricity is impaired, and this causes seizure to the mold and mold wear in the pressing process.
However, since the baking temperature and time vary depending on the blended resin, it is desirable that the baking temperature and time be appropriately determined within the above range in consideration of properties such as hydrophilicity and adhesion.

As a water washing method, room temperature water or warm water (hot water) can be used. Here, in the specification and claims of the present invention, the term "water wash" means washing using liquid H _{2 O,} may also be used of H _{2 O} any temperature. The water used for water washing may contain impurities or a small amount (for example, 1% by weight or less) of a surfactant, or may be an alkaline aqueous solution having a pH of 10 or less.
Moreover, as a method of washing with water, various methods such as a method of washing with high-pressure water by spraying and a method of washing by immersing (immersing) in a washing tank (water tank) can be used. In addition, when the aluminum fin material 10 is immersed in the water washing tank and washed with water, a large amount of the material removed from the coating film of the aluminum fin material 10 is dissolved in the water in the water washing tank. May reattach to the surface of the aluminum fin material 10. Therefore, during water washing, it is desirable to maintain the quality of the water by taking measures such as replenishing fresh water in the water washing tank as necessary.

Conditions such as the water cleaning method, water temperature, and time may be appropriately adjusted depending on the composition and thickness of the coating film of the aluminum fin material 10 to be cleaned. For example, when washing with high pressure water by spraying, the water pressure can be 0.1 to 0.5 MPa, and the water temperature can be washed at room temperature to 80 ° C. for 1 to 10 seconds. Moreover, when wash | cleaning by immersing the aluminum fin material 10 in which the coating film was formed in the washing tank, water temperature can wash | clean by immersion for 5 to 60 second at room temperature-80 degreeC. By washing with water under such conditions, the polymer compound having the polyoxyethylene chain as the main component of the hydrophilic coating 14 can be made 0.01 g / m ² or more and 0.1 g / m ² or less.

In the case where the content of the polymer compound having the polyoxyethylene chain as a main component in the hydrophilic coating 14 is less than 0.01 g / m ² , the lubricity of the aluminum fin material 10 becomes insufficient at the time of pressing, Problems such as processing defects, mold wear, and poor drying of press oil occur. On the other hand, if the content of the polymer compound having the polyoxyethylene chain as a main component in the hydrophilic coating 14 exceeds 0.1 g / m ² , the lubricity of the aluminum fin material 10 becomes too large, and the slits during press working Cutting failure occurs in the process. Further, the wear of the mold is promoted and the mold life is shortened. In addition, a predetermined shape cannot be obtained due to excessive sliding, and there is a possibility that the hole position of the collar 11 may be displaced. When a shift occurs in the hole position of the collar 11, the shape of the heat transfer tube does not match the hole position of the collar 11 when a hairpin-shaped heat transfer tube (not shown) inserted so as to connect the two collars is inserted. Therefore, the insertability is deteriorated.

By the above, the aluminum fin material 10 for heat exchangers according to the present invention can be obtained.
The aluminum fin material 10 of the present invention has a hydrophilic coating 14 containing 0.01 to 0.1 g / m ^{2 of} a polymer compound mainly composed of a polyoxyethylene chain on the surface of a plate 13 made of aluminum or an aluminum alloy. Is formed, the dynamic friction coefficient is set to 0.1 to 0.2. As a result, moderate lubricity is imparted, and seizure to the mold, press wear and cutting failure during press working can be suppressed.
The hydrophilic coating 14 is coated with a coating containing a polymer compound mainly composed of a polyoxyethylene chain having a viscosity of 50 to 5500 mPa · S in a 5% aqueous solution at 25 ° C., and a plate reaching temperature of 120 ° C. It can be formed by washing with water after baking at ˜250 ° C.

FIG. 3 is a perspective view showing a heat exchanger 20 provided with the aluminum fin material 10 of the present invention. The heat exchanger 20 includes the aluminum fin material 10 shown in FIGS. 1 and 2 and a plurality of heat transfer tubes 30. The aluminum fin materials 10 are arranged in parallel at regular intervals, and air flows between the aluminum fin materials 10. The heat transfer tube 30 penetrates the collar 11 of the aluminum fin material 10, and the refrigerant flows through the inside thereof.
Since the heat exchanger 20 shown in FIG. 3 includes the aluminum fin material 10 shown in FIGS. 1 and 2, water attached to the surface of the aluminum fin material 10 (the surface of the hydrophilic coating 14) easily wets and spreads. And water drops are unlikely to occur. For this reason, it is suppressed that the bridge of water is formed between the adjacent wall surfaces of the aluminum fin material 10, and the ventilation resistance of air can be suppressed small. For this reason, even when used over a long period of time, the heat exchange capacity is unlikely to decrease.

As mentioned above, although the aluminum fin material for heat exchangers concerning the present invention, its manufacturing method, and the embodiment of a heat exchanger were explained, each part which constitutes the above-mentioned aluminum fin material for heat exchangers and a heat exchanger is an example. Any change can be made without departing from the scope of the present invention.
Examples of the present invention will be described below, but the present invention is not limited to these examples.

"Preparation of paint for hydrophilic film formation"
Coatings A to J for forming a hydrophilic film were obtained by blending and mixing the resins shown in Table 1 in parts by weight shown in the same table. The coating material was prepared by previously adding water or a solvent containing water as a main component to each resin to prepare an aqueous solution or dispersion having a solid content of 10% by weight, and mixing and mixing these.
The paints A to I form only one layer (lower layer part) in which the resins 1 to 3 are blended according to the respective weights. Moreover, the coating material J shall form the upper layer part which consists of the lower layer part which mix | blended resin 1-3 according to each weight degree, and polyethyleneglycol.
Polyethylene oxides 1 to 5 have different viscosity average molecular weights, and thereby different viscosities in a 5% aqueous solution at 25 ° C.
In addition, a mixture of acrylic acid, 2-hydroxyethyl methacrylate, acrylonitrile, and acrylamide copolymer used as the resin 1 of the paints G to I has a weight ratio of acrylic acid, methacrylate-2-hydroxy methacrylate. Ethyl, acrylonitrile, and acrylamide copolymer are mixed in the order of 20: 5: 5: 2.
The viscosity average molecular weights of polyethylene oxides 1 to 5 are as follows. It is. The viscosity average molecular weight of polyethylene glycol is 20000.

"Production of aluminum fins"
(Sample Nos. 1 to 20)
Any one of the above-mentioned paints A to I is applied on a plate made of an aluminum alloy of JIS standard A1050 treated with phosphoric acid chromate using a bar coater, and then baked in an oven for 30 seconds as the plate arrival temperature described in Table 2 And the coating film was cured. Next, the plate material with the coating film formed on the surface is dipped and washed under the water washing conditions shown in Table 2 to obtain a high amount of polyoxyethylene chains as a main component on the surface of the plate material by the remaining amount shown in the table. Sample No. in which the molecular compound remained and the hydrophilic film having the film thickness described in the table was formed. Aluminum fin materials of Examples 1 to 20 and comparative examples were produced.
However, sample no. In No. 20 (Comparative Example), the lower layer paint was applied and baked, and then the upper layer paint was applied and baked. That is, the water washing process is not performed in either the lower layer portion or the upper layer portion. The film thickness of the lower layer part and the upper layer part and the conditions of the baking process are all the conditions described in Table 2 (the film thickness is 0.7 μm in total of the lower layer part 0.6 μm and the upper layer part 0.1 μm). Moreover, the residual amount of the high molecular compound which has a polyoxyethylene chain as a main component of Table 2 is a total value of a lower layer part and an upper layer part.
In addition, the residual amount of the high molecular compound which has a polyoxyethylene chain as a main component was computed based on the weight difference before and after washing | cleaning by water for 24 hours what was produced by the method similar to each sample.

"Evaluation"
Sample No. prepared above The aluminum fin materials of Examples 1 to 20 and Comparative Example were evaluated for the dynamic friction coefficient, hydrophilicity, the effect of suppressing poor slit cutting, and the effect of suppressing seizure to the mold. The results are shown in Table 3. The evaluation method is as follows.

(1) Lubricity (dynamic friction coefficient)
Using a Bowden friction coefficient measuring instrument (Tribostar TS-501, manufactured by Kyowa Interface Chemical Co., Ltd.) (steel ball size φ9 / 32 inch, load 200 g), a one-cycle test was conducted without applying press oil to the sliding surface. The dynamic friction coefficient of each aluminum fin material surface was measured.
As described above, it is desirable that the dynamic friction coefficient is 0.1 to 0.2.
(2) Hydrophilicity (water contact angle)
About each aluminum fin material, after performing water washing by running water for 24 hours (pretreatment), the water contact angle was measured and hydrophilicity was evaluated.
In addition, as an aluminum fin material, if a water contact angle is 20 degrees or less, it becomes possible to discharge | emit water droplets, such as condensed water, rapidly, and is desirable.
(3) Suppressing effect of slit cutting failure For each aluminum fin material, pressing was performed up to 20000 shots, and the occurrence of cutting failure in the slit process was examined. This result was evaluated according to the following criteria.
○: No slit cutting failure.
X: There is a slit cutting defect.

(4) Suppression effect of seizure to mold For each aluminum fin material, the color inner surface of the press-molded product after 20,000 shots of press work was observed to evaluate the seizure to the mold. This result was evaluated according to the following criteria.
○: Burn-in could not be confirmed.
X: Burn-in was confirmed.

From the results shown in Table 3, all the examples (samples Nos. 1 to 13) of the aluminum fin material according to the present invention have good lubricity, hydrophilicity, the effect of suppressing slit cutting failure, and seizure to the mold. It was confirmed to have an inhibitory effect.
In contrast, sample no. In the aluminum fin materials of Comparative Examples 14 to 17, the dynamic friction coefficient exceeds 0.2 and the lubricity is insufficient. Therefore, seizure to the mold is observed on the inner surface of the color of the molded product after press working. It was done. On the other hand, sample No. In the aluminum fin materials of Comparative Examples 18 to 20, the dynamic friction coefficient was too small (less than 0.2), and slipping occurred in the slit process during press working due to excessive slip.
As described above, the superiority of the example was confirmed with respect to the comparative example, and the effect of the present invention was confirmed.

  DESCRIPTION OF SYMBOLS 10 ... Aluminum fin material, 11 ... Collar, 12 ... Slit, 13 ... Plate material, 14 ... Hydrophilic film, 20 ... Heat exchanger, 30 ... Heat transfer tube

Claims (7)

A hydrophilic coating containing 0.01 to 0.1 g / m ^{2 of} a polymer compound mainly composed of polyoxyethylene chains is formed on the surface of a plate made of aluminum or an aluminum alloy, and the surface has a dynamic friction coefficient of 0. 1 to 0.2 aluminum fin material,
The hydrophilic film is formed by applying a paint containing a polymer compound having a polyoxyethylene chain as a main component, performing baking, and then washing with water. .   2. The heat exchange according to claim 1, wherein the polymer compound having a polyoxyethylene chain as a main component contained in the hydrophilic film has a viscosity of 50 to 5500 mPa · S in a 5% aqueous solution at 25 ° C. 3. Aluminum fin material for dexterity.   The aluminum fin material for a heat exchanger according to claim 1 or 2, wherein the baking is performed at a plate arrival temperature of 120 ° C to 250 ° C.   A heat exchanger comprising a plurality of the aluminum fin materials for a heat exchanger according to any one of claims 1 to 3. By applying a paint containing a polymer compound mainly composed of polyoxyethylene chains on the surface of a plate material made of aluminum or an aluminum alloy, baking, and then washing with water, the polyoxyethylene chains are composed of the main components. The manufacturing method of the aluminum fin material for heat exchangers which forms the hydrophilic film which made the residual amount of the high molecular compound to perform 0.01-0.1 g / m < ² >.   The aluminum fin material for a heat exchanger according to claim 5, wherein the polymer compound having a polyoxyethylene chain as a main component has a viscosity of 50 to 5500 mPa · S in a 5% aqueous solution at 25 ° C. Manufacturing method.   The method for producing an aluminum fin material for a heat exchanger according to claim 5 or 6, wherein the baking is performed at a plate arrival temperature of 120C to 250C.

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