JP2002180272A - Aluminum material having microporous anodic oxide film, and aluminum formed body and fin material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aluminum material which can withstand forming and hardly causes peeling and in which a functional film can be uniformly provided to a part requiring the film in the case where the material is made into a formed article and also to provide a formed body using the material and also a fin material for a heat exchanger, etc. SOLUTION: The aluminum material has a metallic base material 1 composed of aluminum or aluminum alloy, and an undercoat layer 2 composed of a porous anodic oxide film of 5-30% porosity formed on the surface of the metallic base material 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aluminum material having excellent adhesiveness to a metal substrate and excellent gas release, an aluminum molded product and a fin material.

[0002]

2. Description of the Related Art Although stainless steel materials have been widely used as surface materials of vacuum chambers in vacuum equipment, stainless steel materials have a large specific gravity, heavy weight, poor thermal conductivity, and a vacuum atmosphere. Attempts have been made to apply an aluminum material or an aluminum alloy material for reasons such as high gas release from the surface. However, aluminum material is M
When a semiconductor film such as GaAs is formed by a BE apparatus or the like, there is a problem that the film is easily corroded when exposed to a corrosive etching gas. It has been proposed to form a film. However, since this kind of ordinary anodic oxide film is a porous film and has a myriad of fine pores on the surface, the components present in these fine pores are released into a vacuum as gas. Therefore, when a vacuum chamber is manufactured from an aluminum material provided with an anodized film, there is a possibility that a problem may occur in gas release properties.

[0003] For example, non-porous and porous anodic oxide films are known. Of these, a porous anodic oxide film is formed by growing a porous layer on a nonporous barrier layer formed on the surface of an aluminum plate. In such a case, the value obtained by dividing the area of the holes by the total area is known as the porosity, and about 60 to 70% of the porosity is widely used in a usual porous anodic oxide film. ing.
Further, this kind of porous anodic oxide film is subjected to a pore-sealing treatment of exposing it to hot steam for the purpose of closing the pores of the porous layer. It is said that the pores can be closed by exposing the porous layer to partial hydration and swelling the porous layer by exposing it to hot water in this way. In some cases, nickel or cobalt acetate or chromate is added to hot water to precipitate hydrates of these metals in pores to promote the sealing effect.

[0004] However, in the porous anodic oxide film treated by the sealing treatment, moisture and other component ions remain in the sealed portion. When the provided aluminum plate material is used as various constituent members or vacuum equipment wall materials, component gases of moisture and various hydrates may be released from the surface portion of these structural members or from the wall surface of the vacuum equipment, Depending on the application, the outgassing may be a problem.

[0005]

SUMMARY OF THE INVENTION The present inventors have conducted research and development on a technique for obtaining a nonporous anodic oxide film for the purpose of improving the gas release property of an aluminum material having an anodic oxide film. Is disclosed in JP-A-5-25694.
JP-A-8-283991, JP-A-8-28399
No. 0, Japanese Patent Application Laid-Open No. 9-184093, and the like. If it is an aluminum material with a nonporous anodic oxide film obtained by the technology proposed in these patents, an aluminum material with excellent thermal conductivity, low gas release from the surface, and excellent corrosion resistance Now available. However, the present inventors have studied this nonporous anodized film, and even if it is not nonporous,
The present inventors have found that an anodic oxide film having a few holes can provide an aluminum material having excellent corrosion resistance, low gas emission, and excellent adhesion to aluminum substrate, and arrived at the present invention.

[0006] Next, the present inventors are conducting research on application of this kind of aluminum material having a nonporous anodic oxide film, and further apply another type of coating film on the surface of the aluminum material. The adhesion of the coating film when formed,
As a result of studying various aspects such as moldability when molding into a molded body such as a fin material, the present invention has been reached.

Further, the inventors of the present application have been conducting research and development on the structure of an aluminum material in which an anodized film is formed as a base layer on the surface of the aluminum material and a functional film such as a photocatalytic layer is formed thereon. As a result of the research, the present invention was reached.

Next, conventionally, a porous anodic oxide film generally has irregularities on its surface. Therefore, when another resin layer or film is laminated on the surface of the anodic oxide film, another resin As the bottom side of the layer or film is formed in a way that bites into the irregularities on the surface of the anodic oxide film, it exerts an anchor effect,
It has been considered that the adhesiveness of the resin layer and the film laminated thereon is excellent. However, the diameter of the pores existing on the surface of the porous anodic oxide film is considered to be extremely small, about several hundreds of mm, so that the resin layer or the film itself penetrates into such fine irregularities and the anchor effect. The present inventors believe that the porous anodic oxide film does not have good adhesion. Even if the sealing process is performed, moisture and ions remain in the pores of the porous layer. Therefore, another resin layer or film is laminated on the anodic oxide film, and during the laminating process. 1
When a drying process or a baking process of heating to 00 ° C. or more is performed, the present inventors do not necessarily perform the process of forming the resin layer or the film on the porous anodic oxide film due to the effect of water or ions in the pores evaporating or evaporating. We believe that the adhesion is not good.

Based on the above background, the present invention provides a film which can withstand molding, is hardly peeled off, has good adhesion to a film, has a low possibility of releasing moisture and gas, and has a portion necessary for a molded product. It is an object of the present invention to provide an aluminum material which can uniformly provide a functional film such as a photocatalyst layer and has excellent productivity and a fin material suitable for a molded article and a heat exchanger using the same.

[0010]

In order to solve the above-mentioned problems, the present invention provides a metal base made of aluminum or an aluminum alloy and a porosity of 5 formed on the surface of the metal base.
-30% of a microporous anodized film. In order to solve the above problems, the present invention provides a metal substrate made of aluminum or an aluminum alloy, and a porosity of 5 to 5 formed on the surface of the metal substrate.
An aluminum material having a 30% microporous anodic oxide film and an underlayer is formed by molding. In order to solve the above-mentioned problems, the present invention provides a metal base made of aluminum or an aluminum alloy, and a base layer made of a microporous anodized film having a porosity of 5 to 30% formed on the surface of the metal base. And an aluminum material comprising: The microporous anodic oxide film having a porosity of 5 to 30% formed on the metal base material has low gas release properties, excellent adhesion to the metal base material, good corrosion resistance, and other components. Excellent adhesion of the film when a functional film is formed.

In the present invention, a functional film may be formed on the microporous anodic oxide film. Further, in the present invention, a lubricating layer may be formed on the functional film. The function of the functional film is added to the aluminum material, the aluminum molded body, and the fin material by the functional film formed on the anodic oxide film. If a lubricating layer is formed on the anodized film, an aluminum material that can withstand plastic working can be provided.

[0012]

Embodiments of the present invention will be described below with reference to the drawings, but the present invention is not limited to the following embodiments. FIG. 1 shows a first embodiment in which the aluminum material according to the present invention is applied to a photocatalyst precoat molding material. The photocatalyst precoat molding material A of the first embodiment is a plate-like metal substrate made of aluminum or an aluminum alloy. An aluminum material B consisting of a material 1 and an underlayer 2 formed on the surface of the metal substrate 1, a photocatalyst layer (functional film) 3 coated on the underlayer 2, and a photocatalyst layer 3 A lubricating layer 4 coated on the upper surface is provided to form a plate.

The metal substrate 1 is made of aluminum or an aluminum alloy, and is made of pure aluminum based on JIS1000, Al-Cu based on JIS2000, etc.
JIS 3000-based Al-Mn-based, JIS 4000-based Al-Si-based, JIS 5000-based Al-Mg-based, JI
Any type of Al-Mg-Si type such as S6000 type and Al-Zn-Mg type such as JIS7000 type may be used.

Pure aluminum-based materials such as JIS1000-based, JIS2000-based, JIS300-based
Since the system 0 is used for various parts and the like, the present invention can be applied to these applications.

[0015] Since the JIS 4000 type is used for building panels and the like, the present invention can be applied to these applications. The JIS 5000 type is widely used for interior / exterior boards, decorative parts, nameplates, etc., so that the present invention can be applied to these applications. Since the JIS 6000 series is used for construction, decorative articles, etc., the structure of the present invention can be applied to these uses. Since JIS 7000-based materials are used for fin materials and the like, the present invention can be applied to these applications.

The above-mentioned photocatalyst precoat material A
Among these applications, are fin materials for heat exchangers that require fungicide resistance, food containers that are kitchen aluminum products that require antibacterial and antifungal properties, range hoods, ventilation fan covers, range fences , A range cover, a range underlay, various panels that require antifouling properties, a BS antenna, and the like. Therefore, the aluminum base material B of the present invention can be used for the various uses exemplified above with the metal base 1 provided with the base layer 2 described below.
Can be applied.

The underlayer 2 is formed by anodizing the metal substrate 1. In this anodizing treatment (so-called alumite treatment), an anodized film is formed by anodizing treatment in which aluminum or an aluminum alloy constituting a base material is immersed in an electrolytic solution to perform anodizing. With such an anodizing treatment, a porosity of 5
A microporous anodized film (microporous alumite film) of up to 30% (more than 5% and not more than 30%) can be formed. Here, the porosity is a value obtained by dividing the area of the portion where the holes are formed in the measurement region on the surface of the anodic oxide film by the total measurement area, that is, porosity = (area with holes) /
(Total measurement area). The porosity of the microporous anodized film is in the range of 5 to 30% described above, but is more preferably in the range of about 5 to 10%. A method for producing a microporous anodized film having a porosity of 5 to 30% by anodizing treatment will be described later.

The underlayer 2 is for preventing the adhesion between the metal substrate 1 and the photocatalyst layer 3 from being lowered, and the adhesion between the substrate 1 and the photocatalyst layer 3 for these layers is prevented. If there is an oxide layer or the like having a poor quality, problems such as peeling of the photocatalyst layer 3 from the oxide layer during plastic working are caused. In this respect, the underlayer 2 of the microporous anodic oxide film described above has good adhesion to the substrate 1 and also exhibits good adhesion to the photocatalyst layer 3. I do.
Here, if the film used as the underlayer of the photocatalyst layer 3 is an organic film, the underlayer is damaged by the organic substance decomposition action exerted by the photocatalyst layer 3. Good adhesion to 1,
Furthermore, it is important to use a material having good adhesion to the photocatalyst layer 3.

The photocatalytic layer (functional film) 3 is made of Ti
O ₂ (titania), ZnO, SnO ₂ , SrTiO ₃ , W
A photocatalytic semiconductor material selected from O ₃ and Fe ₂ O ₃ is appropriately mixed with a binder such as silica (mainly SiO ₂ ), zirconia (mainly ZrO ₂ ), or titanium peroxide. Then, the mixture can be obtained by applying such a mixture onto the underlayer 2, drying, heating and baking. To apply these mixtures, conventional methods such as roll coating and gravure coating can be applied.

The thickness of the photocatalyst layer 3 is 0.05 to 1
It is preferable that the thickness be in the range of 0 μm. If the thickness of the photocatalyst layer 3 is less than 0.05 μm, it is not possible to secure a sufficient thickness as the photocatalyst layer 3 and it is difficult to obtain a purifying action such as antibacterial and antifungal performance. Further, if the thickness of the photocatalyst layer 3 is more than 10 μm, it has antibacterial and antifungal properties, but wastes a lot of material, which is disadvantageous in terms of manufacturing cost. Among these, TiO ₂ is harmless and chemically stable, and is excited by light by ultraviolet rays to surely exhibit antibacterial and antifungal effects, and exhibit an excellent purification function (action).

The lubricating layer 4 must be a layer containing a nonionic polymer activator such as polyethylene glycol, polyoxyethylene lauryl ether or polyvinyl methyl ether. The nonionic polymer activator used herein includes, for example, polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene alkyl fatty acid amide, polyoxyethylene hydrogenated castor oil ether, polyoxyethylene 12-hydroxystearic acid Ester, polyoxyethylene alkyl fatty acid ester, polyoxyethylene rosin ester, polyoxyethylene glycerin alkyl fatty acid mono or diester, polyoxyethylene trimethylol propane alkyl fatty acid mono or diester, polyoxyethylene pentaerythritol alkyl fatty acid mono or diester, polyoxy Those selected from the group of ethylene polyoxyalkylene ethers are preferred. Further, among these, those having a haze number of 15.0 or more according to the Karabinos method due to the addition of ethylene oxide are preferred.
A nonionic polymer activator having a polyethylene oxide chain having a haze number of about 16 to 18 by the binos method is preferred.

When the above melting point is about 50-60 ° C., Karab
If the outermost layer has a lubricating layer 4 containing a nonionic polymer activator having a polyethylene oxide chain having a haze number of about 16 to 18 according to the inos method, lubricating properties during press working, especially drawless working It is possible to process a molded article such as a fin material with high working efficiency with a low mold damage. As an example of a method for practically producing the nonionic lubricating layer 4 satisfying these conditions, the production method disclosed in Japanese Patent Application Laid-Open No. 7-041696 can be applied.

A predetermined amount of the nonionic polymer activator is dissolved in a solvent such as water, and this coating solution is roll-coated,
The photocatalyst precoat material A provided with the lubricating layer 4 having a cross-sectional structure shown in FIG. 1 can be obtained by applying and drying the photocatalyst layer 3 by an appropriate application means such as a gravure coat. The lubricating layer 4 after drying has a thickness of 0.02 μm or more,
Preferably, it is in the range of 0.02 μm to 1.0 μm. If the thickness of the lubricating layer 4 is less than 0.02 μm, the lubricity in the case of plastic working decreases, resulting in poor processing.
It is easy to cause seizure of the mold. When the thickness of the lubricating layer 4 is greater than 1.0 μm, there is no problem in lubricity, but the lubricant is easily wasted, which is disadvantageous in terms of manufacturing cost.

The photocatalyst precoat material A having the above-described structure can be processed into a required shape by plastic working such as pressing, drawing, and ironing, and used for various purposes. In this plastic working, the lubricating layer 4 provided on the surface of the photocatalyst precoat material A reduces friction with a mold or a die during plastic working. Does not occur. Then, after molding into a desired shape, the processed product can be obtained by removing the lubricating layer 4 as necessary by means such as washing. The lubricating layer 4 may remain in the form of a molded product, or may be removed by means such as washing.

Since the molded article made of the photocatalyst precoat molding material A manufactured as described above has the photocatalyst layer 3 uniformly on the entire surface, the photocatalyst layer 3 is irradiated with energy light such as ultraviolet rays. Then, electrons are excited on the surface portion of the photocatalyst layer 4 which is in contact with air, and O ²⁺ or OH
^-Can be generated, whereby the action of decomposing organic substances can be obtained, and the photocatalyst can obtain a purifying function (action) such as antibacterial, antifungal and purifying action on the surface of the molded article.

Here, if the molded article is a fin material for a heat exchanger, mold can be prevented from being generated on the fin material, so that a heat exchanger having a fin material exhibiting antibacterial property and antifungal property is provided. be able to. In the case of a fin material for a heat exchanger, since the fin material is used in a state where water droplets adhere to the surface of the fin material, even if the lubricating layer 4 remains on the surface portion after molding, the lubricating layer 4 is formed by water droplets. Since the lubricant layer 4 is gradually removed, the lubricant layer 4 does not need to be particularly removed. When the structure of the present embodiment is used as a molded product, it can be widely used as various molded product applications such as a range hood and a container in addition to the fin material. In addition, it goes without saying that the photocatalyst precoat molding material A of the present embodiment can be widely applied to various uses described above as the constituent material of the base material 1. In this case, an excellent purification function (action) such as antibacterial and antifungal performance can be obtained regardless of the application.

FIG. 2 shows an example of a heat exchanger for an air conditioner provided with a fin material obtained by using the photocatalyst precoat molding material according to the present invention.
A meandering tube 13 is arranged on a fin material (photocatalyst pre-coated molded product) 14 having a configuration in which a large number of fin members are stacked. The heat exchanger B of this structure has a fin material 1
Reference numeral 4 is formed by plastically processing the photocatalyst precoat molding material A described above.

As described above, the fin members 14 of the heat exchanger B are used.
Is composed of the photocatalyst precoat material A, since the photocatalyst layer 3 is uniformly provided on the entire surface of the photocatalyst precoat material A, uniform antibacterial and antifungal effects are achieved over the entire surface of the fin material 14 of the heat exchanger B. A purifying function (action) can be obtained. That is, if the photocatalyst layer 3 is applied in advance to the entire surface of the aluminum plate or aluminum alloy plate before molding, the purification function (action) can be reliably obtained over the entire surface of the fin members 14.

In this embodiment, the embodiment in which the photocatalyst layer 3 is applied to the functional film has been exemplified. However, various functional films can be applied in addition to the photocatalyst layer. For example, if the application requires further corrosion resistance, a corrosion-resistant film (functional film) may be formed instead of the photocatalyst layer as an example of the functional film. A color-forming layer (functional film) may be formed, and in applications requiring abrasion resistance, etc., a film (functional film) having excellent abrasion resistance may be formed in place of the photocatalytic layer. If necessary, a conductive film (functional film) may be formed, and the aluminum material B of the present invention can be applied to various uses by forming a necessary functional film according to various uses.

Next, the porosity used as the underlayer 2 is 5 to 5.
A method for producing a 30% microporous anodized film will be described below. In order to produce a microporous anodized film, the electrolysis is stopped before the film becomes porous to obtain a film that is almost non-porous at the stage before the porous film grows. The preferred method is to do so. As the electrolytic solution used here, one or more solutions of sulfuric acid, phosphoric acid, chromic acid, and oxalic acid can be used. When the base material 1 made of aluminum or an aluminum alloy is anodized using these electrolytic solutions, in the initial stage of electrolysis,
An anodic oxide film called a non-porous barrier layer grows, and when the growth of the non-porous anodic oxide film proceeds to a predetermined stage, the porous layer rapidly grows to form a porous anodic oxide film. A film is formed. However, in this specification, a porous anodic oxide film means a porous layer grown on a nonporous thin barrier layer.

Here, a growth model of this kind of anodic oxide film will be described with reference to FIG. The horizontal axis in FIG. 3 indicates the thickness of the anodic oxide film, and the vertical axis indicates the porosity. Usually, when a porous anodic oxide film is manufactured, a nonporous film having a thickness of about 1000 to 2000 ° is formed. A growth curve in which the porosity sharply rises while the film thickness hardly increases, and the relationship between the film thickness increase and the porosity increase shifts to a proportional relationship when the porosity exceeds 30%. Is shown. The growth curve shown in FIG. 3 is a model example of the anodic oxide film. After the formation, the porosity sharply increases, and then, when the porosity exceeds 30%, the relationship between the increase in the film thickness and the increase in the porosity shifts to a proportional relationship, and the porous anodic oxide film is formed. The tendency to do so is similar.

Referring to the growth model of the anodic oxide film shown in FIG. 3, in order to obtain a microporous anodic oxide film having a porosity of 5 to 30% to be used as the underlayer 2, it is necessary to increase the anodic oxide film during the growth process. In other words, the electrolytic treatment may be stopped in a state where the porosity is low. According to the growth model shown in FIG. 3, since the non-porous layer anodic oxide film having a porosity of 5% or less also exists in the initial stage of electrolysis, the production conditions of the non-porous anodic oxide film described above are not satisfied. Instead, the electrolysis may be stopped at the initial stage of the anodic oxidation treatment when the porous anodic oxide film described below is manufactured, so that the non-porous anodic oxide film may be obtained as the base layer 2.

In order to obtain a microporous anodic oxide film as the underlayer 2, the electrolytic treatment may be stopped under electrolytic conditions such that the film thickness is in the range of, for example, 10 to 1500 °, for example, the porosity is 30% or less. Under these conditions, a more preferable range of the microporous anodic oxide film is a film thickness of 50 to 1000 °,
The porosity is 10%. When one or more of sulfuric acid, phosphoric acid, chromic acid, and oxalic acid are selected as the electrolytic solution used here, generally, an electrolytic voltage (V) × (14 to 1)
It is known that when the thickness (Å) of the anodic oxide film exceeds the value of 6), porosity formation is started. Therefore, if the film thickness is controlled below this voltage, a nonporous anodic oxide film or a microporous anodic oxide film can be formed. From this relationship, when manufacturing the microporous anodized film, the film thickness (Å) is preferably set to be smaller than the electrolysis voltage (V) × 25, and is set to be smaller than the electrolysis voltage (V) × 18. Is more preferable.

The thickness of the microporous anodic oxide film is 1
If it is less than 0 °, it is difficult to obtain corrosion resistance, and if the film thickness exceeds 1500 °, porosity is likely to progress. The preferred range is 10 to 1000 °. 5 to 3 in porosity
Even within the range of 0%, it is preferable to be more than 5% and not more than 20%. In the case of an anodic oxide film having a porosity of 5 to 20%, the water content of the anodic oxide film having a porosity of 20% to 30% is lower. There is an advantage that release can be more effectively suppressed, a decrease in the contact area can be prevented, and film destruction can be easily prevented. From such a viewpoint, the porosity of the microporous anodized film is 5 to 10
% (More than 5% and 10% or less) is preferable.

From the above background, the electrolyte concentration in the electrolytic bath when producing the microporous anodic oxide film is 2%.
It is selected from the range of weight% to the saturated concentration of the electrolyte. A bath temperature of the electrolytic bath of 5 to 30 ° C. is sufficient. In such an electrolytic solution, the aluminum material is connected to a power source and electrolyzed anodicly so as to be an anode even if it is continuous or intermittent. An insoluble conductive material such as a carbon electrode is used for the cathode. As the electrolytic current, a direct current or the like is used. In the direct current electrolysis, a direct current density of 0.5 to 1.5 A /
The electrolysis is performed in about dm ² and the electrolysis time is several seconds to about 10 minutes.

The applied voltage for producing the microporous anodic oxide film is about 10 to 20 V since a thickness of the oxide film formed with respect to a voltage of 1 V is about 10 ° with respect to a direct current. It is preferably in the range of about 14-18V. By this electrolysis, a thickness of 10
A uniform microporous anodic oxide film having a thickness of ~ 1500 °, preferably 50-1000 °, is formed.

FIG. 4 is a model diagram of the cross-sectional structure of the porous anodic oxide film having a high porosity shown in FIG. 3, and FIG. 5 is obtained by setting the porosity shown in FIG. 3 to about 10%. It is a model figure of the cross-sectional structure of a microporous anodic oxide film near non-porous. The porous anodic oxide film 10 shown in FIG. 4 has a non-porous barrier layer 10a and a porous layer 10b grown thereon.
The microporous anodic oxide coating 11 shown in FIG. 5 has a cross-sectional structure in which some irregularities are present on the surface without growth of pores. Note that the microporous anodic oxide film 11 also has 5 to 30% of holes, so that the microporous anodic oxide film 11 has holes of this ratio. However, in FIG. 5, clear holes are not shown.

Microporous anodic oxide film 1 having the structure shown in FIG.
If it is 1, when it comes to the gas release property, it is much less than the porous one, and has a low gas release property close to the non-porous anodic oxide film according to the patent application of the present inventors described above. Obtainable. Further, when examining the anchor effect on the functional film such as the photocatalytic layer 3 laminated on the surface, the anchor effect is higher than that of the nonporous anodic oxide film because the surface has irregularities as compared with the nonporous anodic oxide film. Therefore, the adhesion of the photocatalyst layer 3 is also excellent. Of course, as described above, when the photocatalyst layer 3 is applied and baked because of low gas release property, there is little volatilization and evaporation of water and ions, so that it has a strong effect on peeling and peeling after baking.

In view of the above results, it is considered that the non-porous anodic oxide film, the microporous anodic oxide film, and the porous anodic oxide film are as follows as to the anchor effect and the gas release property of the film. In addition, the microporous anodic oxide film is excellent in satisfying both characteristics. Anchor effect Outgassing Nonporous anodized film × 〇 Microporous anodized film △ 〇 Porous anodized film 〇 (×) ×

[0040]

[Example] 1N30 of pure aluminum based on JIS,
1050, 1200 and JIS 3003, 3004
Thickness of 100 μm, 200
A plurality of μm and 300 μm aluminum substrates (base materials) were prepared. These various substrates were anodized under the following various conditions to form an anodized film. As a condition of the anodic oxidation treatment, when forming a microporous anodized film,
150 g / l sulfuric acid solution, current density 1.3 A / dm ² , 100% for forming nonporous anodic oxide film
g / l boric acid solution and the current density was 3.0 A / dm ² . Under the above conditions, a microporous anodic oxide film having a thickness of 100
A film having a thickness of 800 mm was obtained as a non-porous anodized film having a thickness of 0 mm.

These film thicknesses are the measurement results obtained by embedding a sample in a resin, cutting the sample with a microtome, observing the cross section with a TEM, and directly measuring the film thickness. The method for measuring the porosity of the obtained nonporous anodic oxide film is as follows.
Observing the surface with an electron microscope that can be magnified 100,000 times, measuring and averaging the area ratio of arbitrary 20 holes,
According to the measurement results obtained by this method, a nonporous anodic oxide film having a porosity of 2% was obtained.
It was 0%. Next, a 0.5 μm-thick TiO ₂ layer (photocatalytic layer) is formed on the anodic oxide film on these various substrates, and then a 0.15 μm-thick lubricating layer is formed on this TiO ₂ layer. did. The photocatalyst layer was prepared by mixing 50 parts by weight of a binder mainly composed of SiO ₂ with respect to 50 parts by weight of TiO ₂ powder, and coating the mixture on the surface of an aluminum substrate with a roll coater.
It was formed by heating to 150 ° C. and baking.

The lubricating layer was manufactured as follows. The following raw materials and catalyst are charged into an autoclave, and the air in the autoclave is replaced with nitrogen using nitrogen gas. Thereafter, the internal temperature of the autoclave is raised to 120 ° C., a specified amount of ethylene oxide is blown into the autoclave, the blowing is completed while maintaining the reaction temperature at 120 to 160 ° C., and then the reaction is completed at the same temperature for 1 hour. Thus, a nonionic polymer lubricant was obtained. The raw compound is rosin, the charge amount is 270 g, the number of moles is 0.1, and the catalyst is KOH.
The charged amount was 0.14, the ethylene oxide blowing amount was 880 g, the number of moles was 20 mol, and the yield was 900 g.

The obtained nonionic lubricant is a polyoxyethylene (200) ester. This polyoxyethylene (200) ester was coated on the photocatalyst layer to a thickness of 0.5 mm.
What was coated so as to have a thickness of 15 μm was used as a sample of Example 1. Further, Example 2 had a laminated structure equivalent to that of the sample of Example 1 except that only the thickness of the lubricating layer was 0.02 μm. Examples 1 and 2 are samples using a nonporous (2% porosity) anodic oxide film as a base layer, and the microporous anodic oxide film ( The porosity is 10%), and the other layers are made equal to each other by using a microporous anodic oxide film with respect to the sample of Example 3 and the sample of Example 2. Example 4
Sample.

The sample of Example 1 was the same as the sample of Example 1 except that the same substrate, underlayer and photocatalyst layer of aluminum or aluminum alloy were used, and only the uppermost lubricating layer was omitted. Comparative Example 2 Compared to the sample of Example 1, a structure (substrate + photocatalytic layer) in which both the underlayer and the lubricating layer were omitted was used.
And Compared to the sample of Example 1, the substrate, the underlayer, and the photocatalytic layer were equivalent, and a sample using a lubricant layer having a thickness of 0.01 μm was used as Comparative Example 3. A sample in which the underlayer was omitted from the sample of Example 1 and the photocatalytic layer and the lubricating layer were equivalent was designated as Comparative Example 4.

The samples of Examples 1, 2, 3, and 4 and the samples of Comparative Examples 1, 2, and 3 were subjected to a lubricity measurement test in which the coefficient of friction was measured with a Bowden friction tester. The results are shown in Table 1 below. In Table 1 below, the symbol 〇 indicates that the dynamic friction coefficient was 0.15 or less, and the symbol △ indicates that the dynamic friction coefficient was 0.16.
の も の 0.25, and × mark indicates those having a dynamic friction coefficient of 0.26 or more.

Further, these samples were continuously pressed using a volatile press oil (trade name: AF-2A, manufactured by Idemitsu Oil Co., Ltd.) using a fin press machine manufactured by Hidaka Seiki Co., Ltd.
When a fin material for a heat exchanger was molded using a 9.52φ drawless and a 9.52φ draw with a press number of 10,000 shots, defective molded products and seizure to a mold were evaluated. The results are shown in Table 1 as workability A.
In the workability A of Table 1, a mark with a mark Δ indicates that the molding defect was 5% or less and the baking to the mold did not occur, and a mark with a mark Δ indicated that the molding defect was 5 to 15% and the baking to the mold slightly occurred. Things,
The samples marked with “x” are those in which molding failure is 15% or more and burning to a mold is large.

Next, the above-mentioned sample was subjected to continuous press working without using press oil, and the defect of the molded product and the seizure to a mold were evaluated. The results are shown in Table 1 as workability B. In the workability B of Table 1, a mark with a mark Δ indicates that the molding failure was 5% or less and the baking to the mold did not occur, and a mark with a mark Δ indicated that the molding failure was 5 to 15% and a little baking to the mold occurred. In addition, the samples marked with “x” have a molding defect of 15% or more and a lot of baking to the mold.

[Table 1] Sample type Lubricity Press workability A Press workability B Example 1 (non-porous film) 〇 〇 ２ Example 2 (non-porous film) 〇 〇 ３ Example 3 (microporous Film) 〇 〇 〇 Example 4 (microporous film) 〇 〇 例 Comparative Example 1 × 〇 × Comparative Example 2 × × × Comparative Example 3 △ 〇 △ Comparative Example 4 〇 〇 △

From the results shown in Table 1, the samples of Comparative Examples 1 to 4 have problems in lubricity and any of workability A and workability B, but the samples of Examples 1, 2, 3, and 4 have lubricity. It was found that both the press workability A and the press workability B passed. From this, Examples 1, 2, 3, 4
If the structure of the sample of, having a photocatalytic layer that can withstand plastic processing on an aluminum substrate or an aluminum alloy substrate,
It has been clarified that a uniform photocatalyst layer can be provided to an article subjected to plastic working.

Next, a photocatalyst paint ST- made by Ishihara Sangyo Co., Ltd. was applied to the plurality of substrates on which the underlayer used in Example 1 was formed.
K03 (trade name) with a coating amount of 0.15 g / m ² (0.09 μm film thickness), 0.30 g / m ² (0.18 μm film thickness),
0.60 g / m ² (0.36 μm thick)
Each sample was prepared by baking and drying at 250 ° C. for 30 seconds,
Each contact angle (°) was measured as an initial value. Contact angle meter CA manufactured by Kyowa Interface Science Co., Ltd.
-D was used. Subsequently, these samples were immersed in volatile oil RF-190 (trade name) manufactured by Showa Shell for 2 minutes and then dried, and the contact angle was measured in a state where the residual oil was present after drying.

Next, the dried substrate was irradiated with ultraviolet rays of about 1 mW / cm ² using a black light lamp (BBL lamp), and after 0.5 hour, 1 hour, 3 hours, After 10 hours, after 24 hours,
After 48 hours, the respective contact angles were measured. The above results are shown in Table 2 below. In Table 2, “initial” indicates the contact angle before immersion in the volatile oil, and “oil contamination” indicates the contact angle after immersion in the volatile oil.

[Table 2] Oil contamination BBL lamp Irradiation amount of ultraviolet rays about 1 mW / cm ² Sample irradiation After initial value 0.5 1 3 6 10 24 48 1 0.15 g 22 82 83 87 75 46 19 25 6 2 0.30 g 22 84 81 88 50 20 5 65 3 0.60 g 25 84 83 86 35 11 10 10 5 5

From the results shown in Table 2, the thicker photocatalyst layer (the thickness of the sample 1 was 0.09 μm and the thickness of the sample 2 was 0.1 μm).
18 μm, and the film thickness of Sample 3 is 0.36 μm), it is clear that the ability to decompose residual oil and reduce the contact angle is improved. From the above, 0.09 μm to 0.36
If the structure of the present invention is provided with a photocatalyst layer having a thickness of μm, the contact angle can be significantly increased by irradiating ultraviolet rays for a relatively short time even in a state where residual oil content after oil contamination and drying exists. It was clear that the contact angle after oil contamination could be reduced, and it was clear that the photocatalyst layer decomposed the residual oil of the organic matter, confirming that the photocatalytic function was generated. From this, it can be estimated that each photocatalyst layer can exhibit a purifying function (action) such as antibacterial and antifungal.

[0054]

As described above, according to the method of the present invention, since the base material of the microporous anodic oxide film is provided on the metal substrate of aluminum or aluminum alloy,
A functional film such as a photocatalyst layer formed thereon can be provided on an aluminum or aluminum alloy substrate with good adhesion. In addition, by providing a lubricating layer on a functional film such as a photocatalyst layer, a structure that can withstand plastic working such as press working or extrusion working can be used. If a functional film such as a photocatalyst layer is provided, a molded article made of an aluminum molding material having a functional film such as a photocatalyst layer provided uniformly over the entire surface after plastic working can be obtained. In addition, since it has a base layer of an anodic oxide film, the adhesion of the film laminated thereon is good, and the influence of moisture and ions that evaporate or evaporate when forming a functional film such as a photocatalytic layer can be eliminated. In addition, peeling and peeling of the functional film can be prevented.

When a fin material such as a heat exchanger for an air conditioner is formed by using the aluminum material having the above-described structure, a fin material for a heat exchanger having a functional coating on the entire surface of the fin material can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view showing the structure of a photocatalyst precoat molding material according to a first embodiment of the present invention.

FIG. 2 is a front view showing an example of a heat exchanger provided with a fin material composed of a photocatalyst precoat molding material according to the present invention.

FIG. 3 is a model diagram showing a relationship between a film thickness and a porosity when an anodic oxide film is formed.

FIG. 4 is a model diagram showing a cross-sectional structure of a porous anodic oxide film.

FIG. 5 is a model diagram showing a cross-sectional structure of a microporous anodic oxide film.

[Explanation of symbols]

A: photocatalyst precoat molding material, 1: metal substrate, 2 ...
・ Underlayer (microporous anodized film), 3 ・ ・ ・ Photocatalytic layer (functional film), 4 ・ ・ ・ Lubricating layer, 10 ・ ・ ・ Porous anodized film,
10a: barrier layer, 10b: porous layer, 11: microporous anodized film, B: heat exchanger, 14: fin material (photocatalyst pre-coated molded product).

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B32B 15/04 B32B 15/04 Z 15/20 15/20 C25D 11/04 302 C25D 11/04 302 11 / 18 312 11/18 312 F28F 1/12 F28F 1/12 G F-term (reference) 4F100 AA17B AA20 AA21 AB10A AB31A AJ11 AK54 AR00D AS00C BA02 BA03 BA04 BA10A BA10C BA10D DJ10B EJ12B EJ61 GB51 JK01 JK08AJJA08A BA01A BA01B BA02B BA04B BA48A CD10 DA05 EA11 EB12X EB12Y EB15Y ED04 FA02 FA03 FB23 FB42 4K044 AA06 BA12 BA21 BB03 BB04 BB13 BC05 CA17 CA22 CA53 CA64

Claims (7)

[Claims] 1. A metal substrate comprising aluminum or an aluminum alloy, and an underlayer comprising a microporous anodic oxide film having a porosity of 5 to 30% formed on the surface of the metal substrate. An aluminum material, characterized in that: 2. An aluminum material, comprising a functional film formed on the microporous anodic oxide film. 3. An aluminum material comprising a lubricating layer formed on the functional film. 4. A metal substrate comprising aluminum or an aluminum alloy, and a base layer comprising a microporous anodized film having a porosity of 5 to 30% formed on the surface of the metal substrate. An aluminum molded product obtained by molding an aluminum material. 5. An aluminum molded body, comprising a functional film formed on the microporous anodic oxide film. 6. A metal substrate comprising aluminum or an aluminum alloy, and an underlayer comprising a microporous anodized film having a porosity of 5 to 30% formed on the surface of the metal substrate. A fin material obtained by molding an aluminum material. 7. A fin material comprising a functional film formed on the microporous anodic oxide film.