JP2007268387A - Surface-treated fin material for heat exchanger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a surface-treated fin material for a heat exchanger, by which a malodorous component is decomposed to restrain occurrence of a nasty smell, which has an excellent antibacterial action, the coating film of which is restrained from being damaged by press work to improve the corrosion resistance thereof and which has excellent suppressing effect of occurrence of corrosion under the coating film in a humid environment. <P>SOLUTION: The surface-treated fin material 1 for the heat exchanger is provided with: an aluminum plate 2 or an aluminum alloy plate 2; a photocatalyst layer 3 formed on at least one side of the aluminum plate 2 or the aluminum alloy plate 2; and a water-soluble resin-lubricated layer 4 formed on the surface of the photocatalyst layer 3. The photocatalyst layer 3 comprises titanium dioxide, titanium phosphate or a hydrate of titanium phosphate and a water-soluble resin. If necessary, an inorganic oxide film 5 is arranged between the aluminum plate 2 or the aluminum alloy plate 2 and the photocatalyst later 3. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a fin material used for a heat exchanger, and more particularly to a surface-treated fin material for a heat exchanger that is excellent in decomposition of an odor component, sterilization action and corrosion resistance of a coating film.

2. Description of the Related Art Conventionally, heat exchangers for controlling temperature and humidity are widely used in various air conditioners and various radiators for buildings and automobiles.
The surface of the fin, which is a component of these heat exchangers, causes various odors such as pets and household items that cause odors when air enters and exits for heat dissipation, cooling, air conditioning, etc. Various substances floating in the air such as substances and volatile organic compounds (VOC) present in a general indoor environment are attached.
As a result, during the cooling operation, these adhered substances are detached from the surface of the fin, causing a bad odor, and mold and germs floating in the room propagate on the surface of the fin and cause a bad odor or allergy. There was a problem of releasing the causative substance.
In addition, the adhesion of VOC impairs the hydrophilic treatment of the fin surface, renders the fin surface water repellent, and increases the ventilation resistance due to the attachment of condensed water.
In such a background, a coating film supporting titanium oxide (titanium dioxide) or titanium apatite is formed on the surface of the fin using a binder, etc., and the ultraviolet light is applied to decompose the odor component or to sterilize it. A fin material using a photocatalytic technique that improves the above has been proposed (see, for example, Patent Documents 1 to 4).
Also, photocatalytic technology that improves decomposition and sterilization of odor components by forming a catalyst film (coating film) on the surface of the fin material by sputtering, vapor deposition, CVD, etc. without using a binder. A fin material utilizing the above has been proposed (see, for example, Patent Document 5).
Non-Patent Document 1 describes surface treatment of an air conditioner.
Japanese Patent No. 3093953 (paragraph 0010) JP-A-2005-214469 (paragraphs 0003 and 0016 to 0021) JP 2000-354761 (paragraphs 0007, 0021) JP-A-10-216528 (paragraphs 0011 to 0028, 0061) JP 2000-93807 A (paragraphs 0012 to 0022) Automobile Engineering Society Academic Lecture Preprints 963 1996-5 Pages 153-156

However, the fin material that has improved the decomposition of odor components and the bactericidal action by the conventional photocatalytic technique has the following problems.
If an organic binder is used on the surface of the fin material to support titanium dioxide, the binder itself is oxidized and decomposed by titanium dioxide, which causes a problem that titanium dioxide is peeled off or dropped off.
In addition, when a conventional general inorganic binder such as silica, alumina, organosilane, zirconia, or zeolite is used (for example, Patent Document 4), as shown in Patent Document 2, an inorganic substance is used at the start of condensation such as during cooling operation. There is a problem that peculiar dust odor and cement odor are generated (see Non-Patent Document 1). Even when calcium hydroxyapatite described in Patent Document 2 is used, this countermeasure against odor is not sufficient. Further, in the inorganic binder and the technology of Patent Document 2, odorous substances floating in the room are easily adsorbed on the surface of the inorganic binder, but the photocatalyst is difficult in the place where ultraviolet rays do not hit due to the complicated shape of the heat exchanger. There is a problem that the action of is difficult to work, and the adsorption and desorption of odor components on the surface of the inorganic binder occurs.
In addition, as a method of actually supporting titanium dioxide on the fin surface, it is desirable to carry out by a pre-coating method. However, when forming a fin collar or a slit shape by press working, the technique of Patent Documents 1 and 2 is a coating film. Is hard, and the coating itself tends to crack. When cracks occur in the paint film, in a humid environment where an air conditioner or the like is used, there is a problem that the corrosion resistance deteriorates due to the crack, and corrosion under the paint film occurs and the paint film falls off. It was. Similarly, in the techniques of Patent Documents 1 and 2, since the coating film is hard, the tool is greatly worn during press working. In the technique of Patent Document 3, although the press work itself can be performed by providing the lubricating layer, it is not possible to suppress cracking of the coating film, and thus corrosion occurs.
Furthermore, in the method of forming a coating film without using a binder, a sputtering method, a vapor deposition method, a CVD method, or the like is applied to a pre-coating method in which a catalyst film is formed on a metal plate in advance before forming the fin material. It is difficult to apply a post coating method in which a catalyst film is formed after the heat exchanger is assembled. However, when sputtering method, vapor deposition method, CVD method, etc. are applied to the post-coating method, it takes time and cost to form a catalyst film, and it is difficult to secure a film thickness having a sufficient function. there were.

  The present invention has been made to solve the above-described problems, and by decomposing odor components, the generation of off-flavors is suppressed, the antibacterial action is excellent, and the coating film damage due to press working is suppressed. Thus, the corrosion resistance of the coating film is improved, and a surface treatment fin material for a heat exchanger that is excellent in the effect of suppressing the occurrence of corrosion under the coating film in a humid environment is provided.

  In order to solve the above problems, a surface treatment fin material for a heat exchanger according to claim 1 includes an aluminum plate or an aluminum alloy plate, a photocatalyst layer formed on at least one surface of the aluminum plate or the aluminum alloy plate, and the photocatalyst layer. A fin material comprising a water-soluble resin lubricating layer formed on the surface, wherein the photocatalyst layer has titanium dioxide, titanium phosphate or titanium phosphate hydrate, and a water-soluble resin. And

According to such a configuration, in the fin material of the present invention, the odor component is adsorbed by the titanium dioxide in the photocatalyst layer, and the odor component is oxidatively decomposed to be desorbed as an odorless substance.
In addition, titanium phosphate acts as an inorganic binder and does not generate off-flavors such as dust odor and cement odor at the start of cooling operation peculiar to conventional general inorganic materials such as zeolite, silica and alumina.
Furthermore, by adding a water-soluble resin to the photocatalyst layer, it becomes possible to impart flexibility to the layer, and by providing the water-soluble resin lubrication layer, lubricity of the fin material surface is imparted. It becomes possible to suppress tool wear. As a result, damage to the coating film during press processing of the photocatalyst layer during processing of the fin material can be suppressed to a minimum, and deterioration of the corrosion resistance of the coating film can be suppressed.

In the surface treatment fin material for a heat exchanger according to claim 2, the mass per 1 m ^{2 of the} photocatalyst layer is 5 to 5000 mg, and the mass per 1 m ^{2 of the} water-soluble resin lubricating layer is 10 to 5000 mg. It is characterized by.

According to such a configuration, the fin material of the present invention can sufficiently obtain an active reaction by the photocatalyst necessary for the decomposition of the odor component by setting the mass of the photocatalyst layer within a predetermined range, and has an upper limit of 5000 mg. By doing so, the economy is also improved.
Moreover, the workability of the fin material can be sufficiently improved by setting the mass of the water-soluble resin lubricating layer within a predetermined range.

  The surface treatment fin material for a heat exchanger according to claim 3 has a ratio of titanium dioxide, titanium phosphate or titanium phosphate hydrate, and water-soluble resin in the photocatalyst layer to 100 parts by mass of titanium dioxide. The titanium phosphate or titanium phosphate hydrate is 20 to 2000 parts by mass in terms of anhydride, and the water-soluble resin is 0.01 to 50 parts by mass.

According to such a configuration, the fin material of the present invention controls the ratio of titanium phosphate that acts as a binder to titanium dioxide, so that titanium dioxide is easily fixed and the ratio at which titanium dioxide is exposed to the surface. Increases the performance of the photocatalyst.
In addition, by controlling the ratio of the water-soluble resin to titanium dioxide, sufficient flexibility can be obtained, and even when the water-soluble resin flows out by the dew condensation water, the titanium dioxide itself also It becomes difficult to flow down in the form taken in by this.

  The surface treatment fin material for a heat exchanger according to claim 4, wherein the water-soluble resin used for the photocatalyst layer and the resin used for the water-soluble resin lubricating layer are ethylene oxide water-soluble resin, cellulose water-soluble resin, acrylic It consists of at least 1 sort (s) selected from the group which consists of a water-soluble resin and a polyvinyl alcohol-type water-soluble resin.

  According to such a configuration, the fin material of the present invention can suppress damage to the photocatalyst layer during processing to a minimum, and can suppress deterioration in corrosion resistance.

  The surface treatment fin material for a heat exchanger according to claim 5 is characterized in that an antifungal agent and / or an antibacterial agent is added to the water-soluble resin lubricating layer.

  According to such a configuration, the fin material of the present invention can suppress the growth of mold, germs, and the like until the water-soluble resin lubricating layer flows down.

  The surface treatment fin material for a heat exchanger according to a sixth aspect is characterized in that an inorganic oxide film is provided between the aluminum plate or aluminum alloy plate and the photocatalyst layer.

  According to such a configuration, in the fin material of the present invention, the adhesion between the aluminum plate or aluminum alloy plate and the photocatalyst layer is improved, and the photocatalyst layer is difficult to peel off during processing of the fin material.

The surface treatment fin material for a heat exchanger according to claim 7 is characterized in that a mass per 1 m ^{2 of the} inorganic oxide film is 1-1000 mg.

  According to such a configuration, the fin material of the present invention improves the adhesion between the aluminum plate or aluminum alloy plate and the photocatalyst layer, makes it difficult for the photocatalyst layer to peel off during processing, and applies the coating during processing of the fin material. Film cracking is unlikely to occur.

  The surface treatment fin material for a heat exchanger according to claim 8 is characterized in that in the photocatalyst layer, zirconium ions are further contained in a range of 0.001 to 10 parts by mass with respect to 100 parts by mass of titanium dioxide. To do.

  According to such a configuration, the fin material of the present invention further improves the adhesion between the aluminum plate or aluminum alloy plate and the photocatalyst layer, makes it difficult for the photocatalyst layer to peel off during processing of the fin material, and It is hard for cracks to occur during processing. Further, even after the water-soluble resin is removed by the dew condensation water, it remains in the photocatalyst layer as a zirconium compound, and assists permanent adhesion with the inorganic oxide film.

  According to the present invention, odorous substances adhering to the outside, for example, decomposing odorous components caused by various odor-causing substances such as pets and daily necessities, and general inorganic substances such as silica, alumina, organosilane, zeolite, etc. Generation of off-flavors such as dust odor and cement odor due to the binder can be suppressed, and the growth of fungi and bacteria can be suppressed to improve the bactericidal action. In addition, it is possible to suppress an increase in ventilation resistance due to water repellency on the surface of the fin due to adhesion of VOC. In addition, by suppressing damage to the coating film due to press processing, it is possible to improve the corrosion resistance of the coating film, which was a problem with the photocatalyst coating film using the conventional pre-coating method, and to suppress the occurrence of corrosion under the coating film in a humid environment. The fin material can be provided.

Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.
In the drawings to be referred to, FIG. 1 is an enlarged cross-sectional view schematically showing a configuration of a surface treatment fin material for a heat exchanger according to the present invention, and FIG. 2 is another configuration of the surface treatment fin material for a heat exchanger according to the present invention. It is an expanded sectional view showing typically.

As shown in FIG. 1, the surface treatment fin material 1 for heat exchanger (hereinafter abbreviated as “fin material 1” as appropriate) is an aluminum plate or an aluminum alloy plate (hereinafter collectively referred to as “aluminum plate 2”). ) Is formed on at least one surface of titanium dioxide, titanium phosphate or titanium phosphate hydrate, and a water-soluble resin, and a water-soluble resin lubricating layer is formed on the surface of the photocatalyst layer 3. 4 is formed.
Below, each element which comprises the surface treatment fin material 1 for heat exchangers is demonstrated.

≪Aluminum plate 2≫
As the aluminum plate 2 that can be used in the present invention, an alloy type 5000 series aluminum plate 2 specified in JIS H4000 and an alloy type 1000 series aluminum plate 2 specified in JIS H4000 can be suitably used. It is not limited to these, The aluminum plate 2 which performed various components and tempering as needed can be used. In addition, before forming each coating film on the aluminum plate 2, it is preferable to perform alkali degreasing beforehand.

≪Photocatalyst layer 3≫
The photocatalyst layer 3 is composed of titanium dioxide, titanium phosphate or titanium phosphate hydrate, and a water-soluble resin. The photocatalyst layer 3 is provided by applying these mixtures to the aluminum plate 2 in the form of an aqueous solution, drying or baking.
Here, it is preferable that the mass per 1 m < ² > of the photocatalyst layer 3 is 5-5000 mg.
When the mass per 1 m ^{2 of the} photocatalyst layer 3 is less than 5 mg, it is difficult to obtain an active reaction by a sufficient photocatalyst, so that it is difficult to decompose the attached substance.
On the other hand, the greater the mass of the photocatalyst layer 3, the thicker the photocatalyst layer 3 is, so that the photocatalytic activity function is improved, but it is preferably 5000 mg or less from the viewpoint of economy.

<Titanium dioxide>
Titanium dioxide is a substance that produces photocatalytic action (photooxidation) by producing active oxygen. The feature of photocatalyst by titanium dioxide is that it exerts strong decomposing power when irradiated with light (ultraviolet rays), and its surface is made hydrophilic. It has excellent properties such as. In addition, it is a chemically stable substance that is harmless to the human body.
The general functions of the photocatalyst by titanium dioxide include anti-fogging of glass and mirrors, antifouling, etc. in addition to decomposition, deodorization, deodorization, antibacterial, sterilization and removal of harmful substances.
Titanium dioxide adsorbs odorous components on its surface and, when irradiated with ultraviolet rays, oxidatively decomposes the odorous components into odorless substances such as carbon dioxide and water at room temperature. For this reason, by forming the photocatalyst layer 3 containing titanium dioxide on the surface of the fin material 1, an extremely excellent deodorizing effect can be obtained.
In addition, titanium dioxide decomposes water in the air by its excitation action to generate oxygen and hydroxyl groups, and many hydroxyl groups exist on the surface. Further, since water in the air is further adsorbed by these hydroxyl groups, if the photocatalyst layer 3 is formed on the surface of the fin material 1, a large amount of adsorbed water exists on the surface of the fin material 1. become. Accordingly, such a fin material 1 exhibits excellent hydrophilicity.
Moreover, even when contaminants that inhibit hydrophilicity such as plasticizers and paraffin are adsorbed on the surface of the fin material 1, the contaminants are decomposed and removed by the oxidative decomposition action of titanium dioxide. Excellent stain resistance can be obtained and the inhibited hydrophilicity can be recovered.

<Titanium phosphate or titanium phosphate hydrate>
Titanium phosphate or titanium phosphate hydrate acts as an inorganic binder and fixes titanium dioxide. The inventors have found that titanium phosphate does not generate dust odor or cement odor at the start of cooling operation peculiar to inorganic substances unlike inorganic binders such as silica and zeolite compounds.

<Water-soluble resin>
The water-soluble resin imparts flexibility to the photocatalyst layer 3.
The photocatalyst layer 3 as it is has poor adhesion to the aluminum plate 2 serving as a base material, and thus cannot withstand external stress. However, the photocatalyst layer 3 is flexible by adding a little water-soluble resin. By forming the water-soluble resin lubricating layer 4 on the top, it becomes possible to follow the coating film against external stress due to press working or the like, and it is possible to prevent the coating film from peeling or dropping off.
Further, if the water-soluble resin of the photocatalyst layer 3 is not present, the coating material cracks and falls off from the fin material 1 during the processing (bending, drilling, ironing) of the fin material 1, and the corrosion resistance of the coating film. Deteriorates.
Therefore, the presence of the water-soluble resin of the photocatalyst layer 3 and the water-soluble resin lubrication layer 4 can minimize damage to the photocatalyst layer 3 during processing, and can prevent deterioration of the corrosion resistance of the coating film. .
Here, the water-soluble resin flows down due to the dew condensation water and is decomposed by the photocatalytic action. Therefore, the water-soluble resin is removed after the processing and does not adversely affect the heat exchanger or the human body.
The water-soluble resin applied to the photocatalyst layer 3 contains at least one water-soluble resin among ethylene oxide resin, cellulose resin, acrylic resin, and polyvinyl alcohol (PVA) resin, for example. Preferably there is.
If it does in this way, the follow-up of the coating film to the external stress by press work etc. will become favorable, and generation | occurrence | production of peeling of a coating film, dropping-off etc. can be prevented further.

(Ratio of titanium dioxide and titanium phosphate or titanium phosphate hydrate to water-soluble resin)
The ratio of titanium dioxide and titanium phosphate or titanium phosphate hydrate to water-soluble resin is 20 to 2000 parts by mass of titanium phosphate or titanium phosphate hydrate in terms of anhydride with respect to 100 parts by mass of titanium dioxide. It is preferable that water-soluble resin is 0.01-50 mass parts.
Since titanium phosphate acts as a binder, it is difficult to fix titanium dioxide when the amount is less than 20 parts by mass with respect to 100 parts by mass of titanium dioxide. On the other hand, when the amount exceeds 2000 parts by mass, the rate at which titanium dioxide is exposed on the surface of the photocatalyst layer 3 is lowered, so that the photocatalytic performance tends to deteriorate.
The water-soluble resin imparts flexibility to the photocatalyst layer 3. When the ratio of the water-soluble resin is less than 0.01 parts by mass with respect to 100 parts by mass of titanium dioxide, sufficient flexibility is provided. If it exceeds 50 parts by mass, titanium dioxide itself tends to flow in the form of being taken in by the condensed water, which is not preferable.

<Zirconium ion>
Zirconium ions may be added to the photocatalyst layer 3 as necessary.
By adding zirconium ions to the photocatalyst layer 3, when the inorganic oxide film 5 (see FIG. 2) is provided, the adhesion between the photocatalyst layer 3 and the underlying inorganic oxide film 5 is further improved. This effect is obtained by adding less than 0.001 part by mass of zirconium ion to 100 parts by mass of titanium dioxide. Conversely, when the addition is more than 10 parts by mass, the state of the aqueous solution to be applied cannot be maintained. , The dissolved solid content tends to aggregate.

≪Water-soluble resin lubricating layer 4≫
The water-soluble resin lubrication layer 4 is formed on the surface of the photocatalyst layer 3 and flows down with condensed water while being decomposed by ultraviolet rays after processing.
By providing the water-soluble resin lubrication layer 4, not only seizure of the inner surface of the collar and press-off of the collar during press molding of the fin material 1, but also wear of the mold and the tool due to hard titanium dioxide is suppressed. The Note that if the dynamic friction coefficient on the surface of the fin material 1 exceeds 0.10, the effect of suppressing the seizure of the inner surface of the collar cannot be obtained sufficiently, so the dynamic friction coefficient is preferably 0.20 or less.
Moreover, it is preferable that the mass per 1 m < ² > of the water-soluble resin lubrication layer 4 is 10-5000 mg.
When the mass of the water-soluble resin lubricating layer 4 is less than 10 mg, sufficient workability improvement effect cannot be obtained. If it exceeds 5000 mg, the surface of the fin material 1 becomes sticky due to the moisture absorption effect of the water-soluble resin lubrication layer 4 itself, and problems such as the fin material 1 winding around the pinch roller during press molding tend to occur.
The resin used for the water-soluble resin lubricating layer 4 contains, for example, at least one water-soluble resin among ethylene oxide resin, cellulose resin, acrylic resin, and polyvinyl alcohol (PVA) resin. It is preferable.
In this way, seizure of the inner surface of the collar, press of the collar, and wear of the mold and tool during press molding are further suppressed.

<Anti-mold agent and / or antibacterial agent>
If necessary, an antifungal agent or an antibacterial agent may be added to the water-soluble resin lubricating layer 4.
By adding an antifungal agent and an antibacterial agent to the water-soluble resin lubricating layer 4, it is possible to suppress the growth of mold and germs until the water-soluble resin lubricating layer 4 flows down. For this reason, it is possible to suppress the generation of an extreme odor due to mold or germs at the start of the cooling operation even in a place where it is difficult for the ultraviolet rays to hit.
Antifungal agents and antibacterial agents include, for example, imidazole series such as thiabendazole (TBZ), thiazole series such as 2- (thiocyanomethylthio) -benzothiazole (TCMTB), 1,2-benzisothiazolin-3-one (BIT). ) And other isothiazolone-based substances are preferred because they have both antifungal and antibacterial actions. As the amount of anti-fungal and anti-bacterial agent added is increased, an excellent anti-fungal and anti-bacterial function can be obtained. However, by sufficiently strengthening the intensity of ultraviolet rays, the water-soluble resin lubricating layer 4 is rapidly decomposed. The photocatalyst layer 3 can be exposed, and the antifungal and antibacterial functions of titanium dioxide can be expressed. For this reason, it is sufficient that the photocatalyst layer 3 is contained until the photocatalyst layer 3 is exposed, and the addition amount is not necessarily specified.

≪Inorganic oxide film 5≫
As shown in FIG. 2, an inorganic oxide film 5 may be formed between the aluminum plate 2 and the photocatalyst layer 3.
By providing the inorganic oxide film 5 between the aluminum plate 2 and the photocatalyst layer 3, the adhesion of the photocatalyst layer 3 to the aluminum plate 2 is improved, and the photocatalyst layer 3 is difficult to peel off when the fin material 1 is processed. Examples of the inorganic oxide film 5 include a silica film provided by silica alkoxide, a chromate film such as phosphate chromate and chromate chromate, and a reactive zirconium-based film.
It is preferable that the mass per 1 m < ² > of the inorganic oxide film 5 is 1-1000 mg.
When the mass per 1 m ² of the inorganic oxide film 5 is less than 1 mg, the adhesion of the photocatalyst layer 3 to the aluminum plate 2 is difficult to improve, and when it exceeds 1000 mg, the film may cause cracks during processing.

Next, the surface treatment fin material for a heat exchanger according to the present invention will be specifically described by comparing an example satisfying the requirements of the present invention with a comparative example not satisfying the requirements of the present invention.
<Production of fin material>
As the substrate, an aluminum plate having a thickness of 0.1 mm made of aluminum of alloy number 1200 specified in JIS H4000 was used.
After degreasing the surface of this aluminum plate with 1% caustic soda solution in advance, when providing an inorganic oxide film, a phosphoric acid chromate treatment was performed as a chemical conversion treatment. As the chemical conversion treatment solution, Alsurf (registered trademark) 401/45 manufactured by Nippon Paint Co., Ltd., phosphoric acid 4%, and chromic acid 0.4% were used. At this time, the film thickness of the inorganic oxide film was 400 mm (Cr conversion value measured by the fluorescent X-ray method was 20 mg / m ² ).
As the water-soluble resin of the photocatalyst layer used for the fin material, a mixture of equal amounts of polyethylene glycol (molecular weight 20000) and polyacrylic acid was used. As the water-soluble resin lubricating layer, a mixture of equal amounts of carboxymethyl cellulose and polyethylene glycol (molecular weight 20000) was applied. Thiabendazole (TBZ) was used as an antifungal and antibacterial agent.
Note that Snowtex-O (registered trademark) manufactured by Nissan Chemical Industries, Ltd. was used as the silica of Comparative Example 6.
Table 1 shows the structure of the fin material in each example and comparative example.
However, in Table 1, each (-) column has shown not containing the applicable component. In addition, the numerical value of a titanium phosphate, water-soluble resin, and a zirconium ion is a mass part with respect to 100 mass parts of titanium dioxide.

Next, Table 2 shows examples in which the mass per 1 m ^{2 of the} photocatalyst layer, the ratio of each substance in the photocatalyst layer, and the mass per 1 m ^{2 of} the inorganic oxide film were examined.
However, in Table 1, each (-) column has shown not containing the applicable component. In addition, the numerical value of a titanium phosphate, water-soluble resin, and a zirconium ion is a mass part with respect to 100 mass parts of titanium dioxide.
Further, the production of the fin material was performed by the same method as described above.

The obtained fin material was subjected to the following tests.
≪Evaluation method≫
(Processability and corrosion resistance)
The fin material was made into a fin by performing press using a drawless die of an ironing method manufactured by Hidaka Seiki Co., Ltd. In performing the press, Idemitsu Kosan Co., Ltd. press oil AF2C was used. Punching was performed under pressing conditions at a processing speed of 250 spm and an ironing ratio of 50%, thereby producing fins in which cylindrical rows of inner diameters of φ 9.80 mm were arranged in 2 rows × 10 stages. At this time, the presence or absence of occurrence of seizure on the inner surface of the collar or poor color shape was confirmed. The evaluation criteria were “◎ (very good)” when no peeling occurred on the inner surface of the collar, “Good” when there was little peeling on the inner surface of the collar, and slight peeling occurred inside the collar. The case where “Δ (applicable)” was given, and the case where seizure occurred on the inner surface of the collar was “× (not applicable)”. In addition, as another processing problem, “× (not applicable)” is also used when a fin material is wound around a pinch roller.
In order to investigate the durability of the fins thus formed in a humid environment, a JISH4001 moisture resistance test was conducted for 960 hours to investigate the occurrence of corrosion. When cracks occur in the coating film during processing, it appears as corrosion in the moisture resistance test, so the evaluation standard is “◎ (very good)”, where no change in surface appearance occurred after the moisture resistance test. “○ (good)” indicates that the appearance of the surface hardly changed, “△ (applicable)” indicates that the appearance changed partially due to corrosion, and “×” indicates that the appearance changed entirely due to corrosion. (Not applicable) ”.

(Hydrophilic, odor)
As a pre-treatment, after immersing the fin material (5 cm × 10 cm) in 240 hr tap water (flow rate: 1 l / min) to remove water-soluble components, this is put in a desiccator having a capacity of 6 l to make the water repellent. 1 g of valeric acid as a substance that can be promoted and adhering to the outside is enclosed at the same time, and the desiccator is placed in an electric furnace at 100 ° C. and kept warm for 24 hours to promote VOC adhesion. It was. Thereafter, the 24 hr fin material was exposed using a black light under conditions where the ultraviolet intensity was 0.7 mW / cm ² .
1 μl of pure water is dropped on the fin material, and the contact angle θ of the resulting water droplet is measured with a goniometer (CA-X250 type, manufactured by Kyowa Interface Science Co., Ltd.). ”(Appropriate)” if it is 10-20 °, “△ (applicable)” if it is 20-40 °, and “× (not applicable)” if it is 40 ° or more. . In addition, a sensory evaluation of the fin material was conducted by panelists who passed the olfactory test established by the Odor-Kaori Environment Association, and the presence or absence of odor was confirmed. At this time, the cement odor peculiar to an inorganic binder and the odor peculiar to valeric acid were simultaneously evaluated as odor types. If no odor is observed at all, “◎”, if some odor is recognized but not valeric acid or cement odor, “○”, if valeric acid or cement odor is recognized but at a level that is not a problem. “△”, and “× (not applicable)” when a clear valeric acid or cement odor was observed.

(Anti-mold)
Samples of two conditions when a fin material (5 cm × 10 cm) is immersed in tap water (flow rate: 1 l / min) to remove a water-soluble component as a pretreatment and when the pretreatment is not performed. Prepared. Then, while exposing the fin material under the condition that the ultraviolet light intensity becomes 0.7 mW / cm ² using black light, “Sadako Yamada et al .: Rapid antifungal activity test method for solid material surface, antibacterial fungus Vol.31, No.11, pages 711 to 717 (2003) ". The mold used was a mixture of three types of mold, black mold (Aspegillus niger), blue mold (Penicillium chrysogenum), and black mold (Cladosporium cladosporoides). The evaluation results were evaluated according to the six levels shown in Table 3 below. For simplicity, “◎ (6), ○ (4-5), Δ (3-2), x (1)” was used.

The test results are shown in Table 4.
As shown in Table 4, in the application examples such as Examples 1 to 4 based on the present invention, characteristics of a certain level or more are shown in each evaluation, and there is no problem of dust odor from the photocatalyst layer itself, which can be applied. there were.
In Comparative Example 5, since no titanium phosphate was added, the adhesion of the photocatalyst layer was weak, and there were difficulties in workability and corrosion resistance.
In Comparative Example 6, since a silica was used instead of titanium phosphate, a cement odor was generated.
In Comparative Example 7, since no water-soluble resin was added to the photocatalyst layer, the corrosion resistance deteriorated due to cracks in the coating film during press working.
In Example 8, since the photocatalyst layer is thin, it is difficult to obtain hydrophilicity, odor, and antifungal properties that are functions of the photocatalyst.
In Example 9, since the water-soluble resin in the photocatalyst layer is small, the corrosion resistance is slightly deteriorated due to cracks in the coating film during press working.
On the contrary, in Example 10, since the water-soluble resin in the photocatalyst layer is too much, titanium oxide flows down together with the water-soluble resin when immersed in running water, so that the function of the photocatalyst is hardly obtained as in Comparative Example 8. .
In Example 11, since the amount of titanium phosphate is too small, the adhesion of the photocatalyst layer is weak, and workability and corrosion resistance are slightly deteriorated.
On the contrary, in Example 12, since the amount of titanium phosphate is too large, the exposed amount of titanium oxide is reduced, and the function of the photocatalyst is hardly obtained as in Examples 8 and 10.
In Example 13, since the mass of the water-soluble resin lubricating layer is too large, a problem of pinch roll winding of the fin material during processing occurs. Moreover, since the photocatalyst layer is difficult to be exposed, the antifungal property tends to be slightly deteriorated.
On the other hand, in Example 14, the mass of the water-soluble resin lubricating layer is too small, so that the color inner surface is slightly seized when the fin material is pressed.
In Example 15, since the mass of the inorganic oxide film is too large, the coating film is easily cracked when the fin material is pressed, and the corrosion resistance is slightly deteriorated.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments, and can be modified without departing from the scope of the present invention.

It is an expanded sectional view showing typically composition of a surface treatment fin material for heat exchangers concerning the present invention. It is an expanded sectional view showing typically other composition of the surface treatment fin material for heat exchangers concerning the present invention.

Explanation of symbols

1 Surface treatment fin material for heat exchanger 2 Aluminum plate (including aluminum alloy plate)
3 Photocatalyst layer 4 Water-soluble resin lubricating layer 5 Inorganic oxide film

Claims (8)

A fin material comprising an aluminum plate or an aluminum alloy plate, a photocatalyst layer formed on at least one surface of the aluminum plate or aluminum alloy plate, and a water-soluble resin lubricating layer formed on the surface of the photocatalyst layer,
The photocatalyst layer comprises titanium dioxide, titanium phosphate or titanium phosphate hydrate, and a water-soluble resin. ^{2. The} surface for a heat exchanger according to claim 1, wherein a mass per 1 m ^{2 of the} photocatalyst layer is 5 to 5000 mg, and a mass per 1 m ² of the water-soluble resin lubricant layer is 10 to 5000 mg. Processing fin material.   The ratio of titanium dioxide, titanium phosphate or titanium phosphate hydrate, and water-soluble resin in the photocatalyst layer is such that titanium phosphate or titanium phosphate hydrate is anhydrous with respect to 100 parts by mass of titanium dioxide. The surface-treated fin material for a heat exchanger according to claim 1 or 2, wherein the surface treatment fin material is 20 to 2000 parts by mass and the water-soluble resin is 0.01 to 50 parts by mass.   The water-soluble resin used for the photocatalyst layer and the resin used for the water-soluble resin lubricating layer are a group consisting of ethylene oxide-based water-soluble resin, cellulose-based water-soluble resin, acrylic-based water-soluble resin, and polyvinyl alcohol-based water-soluble resin. The surface-treated fin material for a heat exchanger according to any one of claims 1 to 3, wherein the fin is made of at least one selected from the group consisting of:   The surface treatment fin material for a heat exchanger according to any one of claims 1 to 4, wherein a fungicide and / or an antibacterial agent is added to the water-soluble resin lubricant layer.   The surface treatment fin for a heat exchanger according to any one of claims 1 to 5, wherein an inorganic oxide film is provided between the aluminum plate or the aluminum alloy plate and the photocatalyst layer. Wood. The mass per 1 m < ² > of the said inorganic oxide membrane | film | coat is 1-1000 mg, The surface treatment fin material for heat exchangers of any one of Claims 1-6 characterized by the above-mentioned.   The photocatalyst layer further contains zirconium ions in a range of 0.001 to 10 parts by mass with respect to 100 parts by mass of titanium dioxide. The surface treatment fin material for heat exchangers as described.

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