JP2018115836A - Air-conditioning fin material for indoor equipment featuring low odors and water contents, and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fin material including a coating consisting of two coats, which has an extremely low water content and therefore prevents an odor, and can also secure high hydrophilicity.SOLUTION: A fin material has a core material composed of aluminum or aluminum alloy, and a urethane resin-made corrosion resistant layer formed on at least one of the front and rear faces of the core material, and a hydrophilic layer. The corrosion resistant layer is composed of an anionic urethane resin having a polyester skeleton. The hydrophilic layer is composed of an acrylic resin containing a polymer mainly made of a polyoxyethylene chain. The hydrophilic layer has a water content of 0.01 mg/dmor more and 0.2 mg/dmor less.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a fin material that is applied to an air conditioning fin material for an indoor unit such as an air conditioner and has a low odor and low water content and a method for manufacturing the same.

A heat exchanger for an indoor unit such as a home air conditioner usually has a plurality of aluminum alloy fins arranged in parallel and a plurality of tubes such as copper pipes penetrating these fins. The fin material and the tube are integrated by expanding the tube.
In a heat exchanger, when condensed water aggregates into water droplets and a water droplet bridge is formed between adjacent fins, the air passage is narrowed and ventilation resistance increases, which may reduce heat exchange efficiency. . Aggregated water droplets also induce corrosion of the aluminum material and cause white powder such as aluminum hydrated oxide to adhere to the surface of the fin.
For this reason, in the heat exchanger which consists of a tube and a fin material, the fin material which provided the hydrophilic membrane | film | coat is used as an aluminum fin material.

Currently, a general air-conditioning aluminum fin material for indoor units has a structure in which a chromate film is formed on the surface of an aluminum core material and a hydrophilic coating film is coated. However, in the fin material having a hydrophilic coating film having a one-coat structure, generation of odor due to corrosion of the chromate layer when water is contained in the coating film is a problem. In addition, when the aluminum fin material is washed with an alkaline solution, the hydrophilic coating film may be damaged, and there is a problem that odor is generated due to the damage of the coating film. Furthermore, the hydrophilic coating film itself may contain a small amount of water, and there is a problem that a unique thirst odor is generated when the water content in the coating film evaporates.
As one means for avoiding these problems, a two-layer structure (two-coat structure) that includes a low-hydrophilic hydrophilic layer in addition to a corrosion-resistant underlayer on an aluminum core is considered necessary. Even so, the hydrophilicity needs to maintain the current performance. However, in a coating film having a two-coat structure provided with a corrosion-resistant undercoat layer and a low water content hydrophilic layer, there is a problem that a part of the corrosion-resistant coating film dissolves into the hydrophilic coating side of the surface layer, resulting in a hydrophilic phenomenon. There was a problem that the contact angle of the coating film was high, and a configuration satisfying both low water content and hydrophilic performance was not obtained.

For example, as a fin material having a coating film having a two-coat structure, a resin corrosion-resistant layer and a hydrophilic layer are laminated on the surface of an aluminum substrate via a chromate treatment layer as described in Patent Document 1 below, and the hydrophilic layer surface A fin material having a contact angle of 50 ° or less and a water content of the hydrophilic layer surface of 400 mg / dm ² or less is known.

JP2013-092351A

Since it is difficult to achieve both hydrophilicity and corrosion resistance in the coating structure of the above-mentioned one-coat configuration, the coating film has the above-mentioned two-coat configuration, and the combination of the resin corrosion-resistant layer and the hydrophilic layer suppresses odor and ensures hydrophilicity. A coating film structure having a two-coat structure targeting both of these has been proposed.
In the coating film structure described in Patent Document 1, when a hydrophilic layer having a low water content is simply used, the hydrophilic capacity on the fin surface is also reduced, so that the condensed water is repelled on the fin surface of the heat exchanger. Since there is a problem that the condensed water is scattered on the inside and the ventilation resistance between the fins is increased, it is problematic in terms of hydrophilic performance to reduce the water content of the hydrophilic layer too much, and the content of the hydrophilic layer is 60 mg / dm 2. ^Two or more are described as necessary.

However, the present inventor has made various studies on the conventional coating film having a two-coat configuration, and it does not mean that odor generation from the fin material can be satisfactorily suppressed, and further improvement in odor characteristics and hydrophilic performance. It seems necessary to secure it.
Under these backgrounds, the present inventors have made various studies on the two-coat film, and developed a method that can significantly reduce the water content of the hydrophilic layer. In the hydrophilic layer treated by this method, Has found that good hydrophilicity can be secured even with a very low water content, and has reached the present invention.

  The present invention has been made to solve these problems, and since it has an extremely low water content, it is difficult to generate odors, and it has a two-coat coating film that can ensure high hydrophilicity. An object is to provide a fin material and a manufacturing method thereof.

This invention is made | formed based on this knowledge, Comprising: It has the following structures.
The fin material for air conditioning for indoor units having a low odor and low water content of the present invention is a corrosion resistance of urethane resin formed on at least one of a core material made of aluminum or an aluminum alloy and the front and back surfaces of the core material. An acrylic resin comprising a layer and a hydrophilic layer of an acrylic resin, wherein the corrosion-resistant layer is made of an anionic urethane resin having a polyester skeleton, and the hydrophilic layer contains a polymer mainly composed of polyoxyethylene chains The water content of the hydrophilic layer is 0.01 mg / dm ² or more and 0.2 mg / dm ² or less.

In the present invention, the corrosion-resistant layer is preferably made of a fired product of a polymer primer containing urethane resin particles having a particle size of 0.01 μm or more and 0.1 μm or less.
In the present invention, the coating amount of the corrosion-resistant layer is preferably 0.1 g / cm ² or more and 1.0 g / cm ² or less.

In the method for manufacturing an air conditioning fin material for indoor units according to the present invention, a corrosion-resistant base layer made of an anionic urethane resin having a polyester skeleton is formed on at least one of the front and back surfaces of a core material made of aluminum or an aluminum alloy. The corrosion-resistant base layer is baked at a temperature of 80 ° C. or more and 200 ° C. or less to form a corrosion-resistant layer, and a hydrophilic base layer made of an acrylic resin containing a polymer mainly composed of polyoxyethylene chains is formed on the corrosion-resistant layer. After laminating to obtain a laminated coating film, the surface portion of the hydrophilic base layer is partially removed by washing with water or hot water, and the remaining portion after partial removal is a water content of 0.01 mg / dm ² or more, 0. The hydrophilic layer is adjusted to ² mg / dm ² or less.

In the method for manufacturing an air conditioning fin material for an indoor unit according to the present invention, the remaining amount of the film after the water washing or after the hot water washing is 40% or more and 70% or less by weight difference with respect to the water washing or before the water washing. Thus, a hydrophilic layer having a water content of 0.01 mg / dm ² or more and 0.2 mg / dm ² or less can be obtained.

According to the fin material for air conditioning of the present invention, the core material is provided with two layers, a corrosion-resistant layer and a hydrophilic layer. The corrosion-resistant layer is formed from the anionic urethane resin of the base, and the polyoxy By forming a hydrophilic layer from an acrylic resin with a water content of 0.01 mg / dm ² or more and 0.2 mg / dm ² or less of a polymer-containing type mainly composed of ethylene chains, it has excellent adhesion and corrosion resistance. And the fin material for an air conditioning which does not generate | occur | produce an odor, while maintaining the outstanding hydrophilic property can be provided.
Good adhesion to the core material can be obtained when the corrosion-resistant layer is made of a fired product of a polymer primer containing urethane resin particles having a particle size of 0.01 μm or more and 0.1 μm or less.

The fragmentary sectional view of the aluminum fin material concerning the present invention.

Next, specific embodiments of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the heat exchanger fin material 1 of the present embodiment includes a base material 2 made of aluminum or an aluminum alloy, and a chemical film (chromate film) coated on the front and back surfaces of the base material 2. ) 3, a corrosion-resistant layer 4 formed so as to cover the surface of the chemical conversion film 3, and a hydrophilic layer 5 formed so as to cover the surface of the corrosion-resistant layer 4.

  It does not specifically limit as aluminum or aluminum alloy which comprises the base material 2, You may use the aluminum material of the composition generally applied to the base material for heat exchangers suitably. For example, JIS rules A1050, A1100, A1200, A3003 and the like can be cited.

As the chemical conversion film 3, a thin chromate film subjected to chromate treatment or the like can be applied.
The phosphoric acid chromate film is a chemical film chemically formed on the front and back surfaces of the base material 2 by immersing the base material 2 in an aqueous solution of chromic acid or dichromic acid containing phosphate.
This phosphoric acid chromate film imparts corrosion resistance to the base material 2, suppresses the generation of corrosion products on the front and back surfaces of the fin material when using a heat exchanger, and paint adhesion of the corrosion resistant layer 4 provided thereon. It has a function to enhance.

The corrosion-resistant layer 4 is mainly composed of a urethane resin whose ionicity is an anion and whose resin skeleton has a polyester skeleton. When the corrosion-resistant layer 4 made of this ester-based urethane resin is formed on the phosphoric acid chromate film 2, excellent corrosion resistance can be imparted to the fin material 1.
In addition, ester urethane resins are not easily altered even when exposed to direct sunlight, and are excellent in weather resistance. For this reason, by comprising the corrosion-resistant layer 4 with ester urethane resin, the corrosion resistance performance can be reliably maintained regardless of the installation environment of the heat exchanger.
For example, the corrosion-resistant layer 4 is a bar coater formed on the surface of the base material 2 on which the chemical coating 3 is formed with a resin coating made of a polymer primer containing fine urethane resin particles having a particle size of 0.01 μm or more and 0.1 μm or less. The corrosion resistant base layer can be formed by applying a required thickness by a coating apparatus such as a roll coater or the like, and this corrosion resistant base layer can be baked as described later.

  The polymer primer for constituting the corrosion-resistant layer 4 is composed of fine urethane resin particles having a particle size of 0.01 μm or more and 0.1 μm or less and a solvent (for example, tap water, ionic water).

Here, what contains 27.5-33.6 weight part of urethane resin particles with respect to 100 weight part of resin coating materials is preferable. Since the resin paint having such a concentration has an appropriate viscosity, a corrosion-resistant base layer for forming the corrosion-resistant layer 4 can be easily formed on the outer surface of the chemical conversion film 3 with an appropriate deposition amount.
The corrosion-resistant urethane resin polymer primer is an organic substance, and is decomposed if the temperature for baking, which will be described later, is set too high. Moreover, the ionicity of this corrosion-resistant layer 4 is an anion, and even when the hydrophilic layer 5 is laminated thereon as another layer, it has a feature that bleeding is unlikely to occur.
The coating amount after baking of the corrosion-resistant layer 4 is desirably in the range of 0.1 g / cm ² or more and 1.0 g / cm ² or less. If the coating thickness after baking of the corrosion-resistant layer 4 is less than 0.1 g / cm ² , odor may be generated and the corrosion resistance may be poor, and if the coating thickness exceeds 1.0 g / cm ² , the production cost is low. An increase is expected.
The coating amount displayed here is the adhesion amount after baking of the corrosion-resistant layer 4 and is substantially equal to the coating amount of the corrosion-resistant base layer before baking.

The hydrophilic layer 5 is made of an acrylic resin layer containing a polymer mainly composed of a polyoxyethylene chain. The paint used for forming the hydrophilic layer 5 contains a polymer compound represented by HO— (CH ₂ —CH ₂ —O) _n —H.
Examples of the polymer compound represented by HO— (CH ₂ —CH ₂ —O) _n —H include polyethylene glycol and polyethylene oxide. The weight average molecular weight (Mw) of the polymer compound represented by HO— (CH ₂ —CH ₂ —O) _n —H is not particularly limited, but the weight average molecular weight (Mw) is preferably 4000 or more. More preferably, it is in the range of ˜300000. By setting the weight average molecular weight (Mw) to 4000 or more, sufficient coating film adhesion can be obtained during baking. Moreover, when a weight average molecular weight (Mw) exceeds 300000, there exists a possibility that a coating material may raise a viscosity remarkably and may become difficult to paint.
As the polymer compound represented by HO— (CH ₂ —CH ₂ —O) _n —H, two or more kinds having different molecular weights may be mixed and used.
Examples of the hydrophilic component include resins having one or more hydrophilic functional groups among a hydroxyl group, a carboxyl group, an ester group, an ether group, and a sulfonic acid group. More specifically, an acrylic resin mainly composed of polyacrylic acid can be exemplified, but is not limited thereto. It is preferable to use a hydrophilic resin composed of fine particles.
The coating material for forming the hydrophilic layer 5 preferably contains 10 to 40 parts by weight of a polymer compound represented by HO— (CH ₂ —CH ₂ —O) _n —H. By selecting this range, the curing reaction of the coating film during baking can be sufficiently accelerated, and the coating film adhesion of the formed hydrophilic layer 5 can be improved.

A coating made of a polymer primer of a urethane resin for forming the corrosion-resistant layer 4 is applied to the front and back surfaces of the base material 2 on which the chemical conversion film 3 is formed to form a corrosion-resistant base layer. The corrosion-resistant base layer is formed at 80 ° C. or higher and 200 ° C. Baking at the following temperature, and further applying a paint for forming the acrylic hydrophilic layer 5 thereon to form a hydrophilic base layer, baking at 120 ° C. to 220 ° C., and then baking the surface portion of the hydrophilic base layer The fin material 1 having the cross-sectional structure shown in FIG. 1 and having the chemical conversion film 3, the corrosion-resistant layer 4, and the hydrophilic layer 5 on the front and back surfaces of the substrate 2 can be obtained by removing a part of the substrate by washing with water or hot water. .
By performing water washing or hot water washing, the lubricating component in the hydrophilic layer can be removed, and since a large amount of water is contained in this lubricating component, the water content of the hydrophilic layer 5 can be reduced.

A lubricating component is present on the surface of the hydrophilic layer 5 immediately after baking. The lubricating component present on the surface adsorbs moisture, but is an essential part for forming the coating film shape. If the coating film shape is not formed, the hydrophilicity of the hydrophilic layer 5 is adversely affected. For this reason, after baking, the layer which contains many lubrication components on the coating film surface is removed by washing with water or hot water by 40 to 70% by mass, thereby including the lubricating component containing much moisture present on the coating film surface after baking. The layer can be removed. The surface layer containing the lubricating component in the hydrophilic layer 5 is required as an effective lubricating layer when the fin material is processed into a corrugated shape or drilled as a plate-type fin.
If the amount of the coating film removed by washing with water or hot water is less than 40% by mass, it is insufficient for removing the surface layer containing a large amount of water, and the water content increases. If the coating film exceeding 70% by mass is removed, the hydrophilic layer itself may be insufficient.
Baking is necessary to ensure the adhesion of the corrosion-resistant layer 4. If the baking temperature is less than 80 ° C., the adhesion tends to be poor, and the resin constituting the corrosion-resistant layer 4 is decomposed when baking at a temperature exceeding 200 ° C. There is a high risk.

As a method of washing with water or hot water, normal temperature water or warm water (hot water) can be used. Here, in the specification and claims of the present invention, the term "washing or hot water" refers to washed using liquid H _{2 O,} may also be used of H _{2 O} any temperature. Moreover, the water used for washing | cleaning may contain the impurity and a small amount (for example, 1 weight% or less) surfactant, and may be alkaline aqueous solution of pH 10 or less.
Moreover, as a washing | cleaning method, various methods can be used, such as washing by spraying using high-pressure water, and washing by immersing (immersion) in a washing tank (water tank). In addition, when washing | cleaning by immersing in water, when the substance removed from the hydrophilic base layer by washing | cleaning will be in the state melt | dissolved in large quantities in a washing tank, there exists a possibility of reattaching to the fin material 1 in washing. Therefore, during washing, it is desirable to keep the water quality by taking measures such as supplying fresh water to the washing tank as necessary.

  What is necessary is just to adjust conditions, such as a washing | cleaning method, water temperature, time, suitably according to a composition, thickness, etc. of the coating film of the fin material 1 to wash | clean. 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 about 1 second to 10 seconds. Moreover, when wash | cleaning by immersing the fin material in which the coating film was formed in the water washing tank, the water temperature can be immersed for about 1 second-about 10 second at room temperature-80 degreeC. By washing under such conditions, it is possible to remove 30-60% of the thickness of the coating film, it is possible to remove the surface portion having a high water content present in the surface portion of the coating film, The hydrophilic layer 5 having a very low water content can be obtained from the coating film remaining after washing with water or hot water.

The hydrophilic layer 5 has an effect of reducing the contact angle with water. Thereby, the dew condensation water adhering to the fin material surface of the heat exchanger easily wets and spreads, and hardly flows down and aggregates. For this reason, the heat exchanger provided with the fin material 1 and the tube according to the present embodiment can maintain high heat exchange efficiency while keeping the ventilation resistance small even when used under conditions where condensation is likely to occur.
The water content of the hydrophilic layer 5 is adjusted to 0.01 mg / dm ² or more and 0.2 mg / dm ² or less. If the water content exceeds 0.2 mg / dm ² in the hydrophilic layer 5, the risk of odor generation increases when the fin material of the indoor unit is used. In order to make the water content less than 0.01 mg / dm ² , it is necessary to further remove the lubricant. However, if the lubricant is eliminated, the press moldability is affected, so the lower limit of the water content is 0.01 mg / dm ^2. It was.
The water content is the weight of moisture that can be held in the thickness portion corresponding to the surface 1 dm ² of the hydrophilic layer 5 (the portion between the surface and the corrosion-resistant layer), and is a sufficiently dry fin. With respect to the material, the water content is defined as the difference between the weight measured after the whole body is immersed in water at a predetermined depth for 16 hours, with the weight after hot water washing or water washing as the initial weight.

In this embodiment, it is preferable that the amount of adhesion of the hydrophilic layer 5 after washing with water or hot water is in the range of 0.4 g / m ² or more and 0.7 g / m ² .
When the deposition amount of the hydrophilic layer 5 is less than the above range, the effect of providing the hydrophilic layer 5 is not sufficiently obtained, and the contact angle with water on the surface of the heat exchanger is increased (wetting property is lowered). As a result, the condensed water tends to aggregate and the condensed condensed water forms a bridge between the fin materials, which may increase the ventilation resistance. In addition, even if the deposition amount is larger than the above range, no further effect can be obtained, the material cost is increased unnecessarily, and a paint pool in which the coating film adheres excessively at each location of the joined product occurs. , The gap between the fin materials is narrowed. As a result, the ventilation resistance of the heat exchanger increases and the heat exchange efficiency may decrease, so it is not desirable to increase the amount of deposition of the hydrophilic layer 5 more than necessary.

  Further, the corrosion resistant layer 3 has a function of suppressing the corrosion of the base material 2. Thereby, the corrosion of the base material 2 is suppressed, the generation of polar substances (such as aluminum hydrated oxide) accompanying the corrosion of the base material 2 is also suppressed, and the highly polar base material 2 is not exposed on the surface. The surface of the exchanger is in a low polarity state. Here, the odor component easily adheres to a highly polar surface, and the release of the attached odor component causes odor generation. However, the heat exchanger provided with the fin material 1 of the present embodiment has a surface as described above. Since the polarity of the odor is low, it is difficult for odor components to adhere to it, and the generation of odor can be suppressed.

  Moreover, when the heat exchanger provided with the fin material 1 of the present embodiment is applied to a heat exchanger of a domestic air conditioner, it is difficult to generate odor as described above, and is excellent in hydrophilicity. Increase in ventilation resistance is suppressed, and a comfortable indoor environment without odor generation can be realized.

Examples of the present invention will be described below, but the present invention is not limited to these examples.
Preparation of phosphorous chromate-treated fin material (22 mm x 0.1 mm x 45 mm: single-sided clad material (brazing material A4343, core material A3003) and coating shown in Table 1 using the paint and bar coater shown below A coating film serving as a base of the corrosion-resistant layer was formed in an amount, and each coating film was baked at the temperature shown in Table 1.
Then, the coating material used as the origin of a hydrophilic layer was formed by coating the coating material used as the origin of a hydrophilic layer with the coating amount of 1 g / m < ² > using the resin shown in Table 1 below, and baked at 120-22 degreeC. .
The fin material on which the coating film was formed was washed with hot water at 60 ° C. for 10 seconds or with water at 15 ° C. for 10 seconds to obtain a fin material covered with a corrosion-resistant layer and a hydrophilic layer.

<Evaluation>
About the fin material sample produced by each Example and each comparative example, water content, hydrophilicity, odor (initial stage), odor (after a wet test), corrosion resistance, adhesiveness, and residual amount were evaluated. The conditions for evaluation are shown below.
“Water content”: The obtained fin material was cut into a size of 15 cm × 15 cm, and the water content was measured using this cut piece. The water content was measured by the difference in weight between dry and wet water. Samples with a water content in the range of 0.01 mg / dm ² or more and 0.2 mg / dm ² or less have a circle mark, a water content less than 0.01 mg / dm ² , or a water content greater than 0.2 mg / dm ^2. The samples are shown in Table 2 with x marks.
The time of drying is the weight measured under the conditions after the above-mentioned hot water washing or water washing and after drying at 80 ° C. for 20 minutes in a drying furnace, and the water content is the weight of the cut piece after the above water washing or water washing. .

  “Hydrophilicity”: The contact angle of the obtained fin material was measured after 14 cycles of drying cycle (by a dry and wet cycle in which a dry state maintained at 80 ° C. for 8 hours and a state immersed in running water for 16 hours). In Table 2, fins with a contact angle of 40 ° or less are marked with “○”, and fins with a contact angle of 40 ° or more are marked with “x”.

“Odor (initial)”: The obtained fin material was left in a high temperature and humidity chamber at 40 ° C. for 1 hour, and then measured for odor after 2 minutes at room temperature drying. A cross was marked on the sample.
“Odor (after wet test)”: The odor after the wet test specified in JIS4001 was measured for the obtained fin material, and a mark with no odor and a mark with odor were given to the sample with odor.
“Corrosion resistance”: The obtained fin material was subjected to a salt spray test in accordance with JISZ2731, to obtain a rating number (RN). A check mark is given to a fin material of N9.5 or higher. An X mark was given to a fin material of less than N9.5.
“Adhesiveness”: DRY and WET rubbing tests were performed on the obtained fin material, and a non-peeled fin material was marked with a circle as shown in Table 2, and a peeled-off fin material was marked with an X mark. . The DRY and WET rubbing tests show the peeling results when a 1-pound hammer is attached with a Kim towel and reciprocated 10 times on the fin material.
“Remaining amount”: For the obtained fin material, the weight difference before and after washing with water or hot water is converted into percentage, and the fin material having a weight difference of 40% to 70% is marked with ○ in Table 2 and the weight difference of 40 The fin material was marked with “x” for less than% or more than 70% weight difference.

Table 1 below shows the coating amount of the corrosion-resistant layer, the baking temperature, the type of the corrosion-resistant layer, and the type of the hydrophilic layer.
Table 2 below shows water content measurement results, hydrophilicity test results, odor (initial) measurement results, odor (after wet test) measurement results, corrosion resistance measurement results, adhesion measurement results, and residual amount measurement results.

The urethane ester-based resin films of Sample Nos. 1 to 7 shown in Table 1 contain 10 to 15% of n-methyl-2-pyrrolidone, the resin skeleton is an ester, and the ionic property is an anionic urethane-based resin film.
The epoxy film of sample No. 8 shown in Table 1 was an aquatic epoxy resin containing 5 to 10% n-butyl alcohol and 5 to 10% ethylene glycol monobutyl ether.
As the urethane ether ester resin film of Sample No. 9 shown in Table 1, an aqueous urethane ether ester resin containing 5 to 10% of n-methyl 2-pyrrolidone was used.
As the acrylic resin film of Sample No. 10 shown in Table 1, an acrylic resin film containing 24 to 28% of epoxy-modified acrylate resin and 4 to 6% of ethylene glycol monobutyl ether was used.
The epoxy resin film of Sample No. 11 shown in Table 1 was an aqueous epoxy resin containing 5 to 10% n-butyl alcohol and 5 to 10% ethylene glycol monobutyl ether.
For the urethane ether ester resin film of Sample No. 12 shown in Table 1, an aqueous urethane ether ester resin containing 5 to 10% of n-methyl 2-pyrrolidone was used.
As the acrylic resin film of sample No. 13 shown in Table 1, an aqueous acrylic resin film using acrylic acid / acrylamide / 2-hydroxyethyl methacrylate copolymer was used.
The urethane ester resin films of Sample Nos. 15 to 19 shown in Table 1 contain 10 to 15% of n-methyl-2-pyrrolidone, the resin skeleton is an ester, and the anionic urethane resin film is used for ionicity.

As the polymer-containing film mainly composed of polyoxyethylene chains of Sample Nos. 1 to 11 shown in Table 1, a urethane ester resin film having a polyoxyalkylene chain of 10% or more was used.
As the acrylic hydrophilic films of Sample Nos. 11 to 13 shown in Table 1, an aqueous acrylic resin film using an acrylic acid / acrylamide / 2-hydroxyethyl methacrylate copolymer was used.
As the polymer-containing film mainly composed of polyoxyethylene chains of Sample Nos. 14 to 18 shown in Table 1, a urethane ester resin film having a polyoxyalkylene chain of 10% or more was used.

As shown in Tables 1 and 2, the coating amount of the corrosion-resistant layer is set to 0.1 to 1.0 g / m ² , the baking temperature of the corrosion-resistant layer is set to 80 ° C. to 200 ° C., and the urethane ester type is used as the corrosion-resistant layer. The fin material samples of Examples 1 to 7 that were washed with water or washed with water using an acrylic resin containing a polymer mainly composed of a polyoxyethylene chain as a hydrophilic layer had a low water content and had an odor. There are few, and it turns out that it is excellent also in corrosion resistance and adhesiveness.

For these fin material samples, the temperature when baking the corrosion-resistant layer as in the samples of Comparative Examples 8 to 13 is set to a temperature higher than 200 ° C., and a corrosion-resistant layer that is not a urethane ester resin is provided in Table 2. One of the characteristics shown was inferior.
Comparative Examples 16-19 A corrosion-resistant layer of urethane ester resin was used, but the baking temperature was too low or too high, or a sample without a hydrophilic layer, but water content, hydrophilicity, odor, corrosion resistance, adhesion Posed problems in either aspect of the remaining amount.

DESCRIPTION OF SYMBOLS 1 ... Fin material, 2 ... Base material, 3 ... Chemical conversion film, 4 ... Corrosion-resistant layer, 5 ... Hydrophilic layer.

Claims (5)

A core material made of aluminum or an aluminum alloy, and a urethane resin corrosion-resistant layer and a hydrophilic layer formed on at least one of the front and back surfaces of the core material,
The corrosion-resistant layer is made of an anionic urethane resin having a polyester skeleton,
The hydrophilic layer is made of an acrylic resin containing a polymer mainly composed of polyoxyethylene chains, and the water content of the hydrophilic layer is 0.01 mg / dm ² or more and 0.2 mg / dm ² or less. A fin material for air conditioning for indoor units that has low odor and low water content.   The room having a low odor and low water content function according to claim 1, wherein the corrosion-resistant layer is made of a fired polymer primer containing urethane resin particles having a particle size of 0.01 µm or more and 0.1 µm or less. Fin material for air conditioning for aircraft. The room having a low odor and low water content according to claim 1 or 2, wherein the coating amount of the corrosion-resistant layer is 0.1 g / cm ² or more and 1.0 g / cm ² or less. Fin material for air conditioning for aircraft. A corrosion-resistant base layer made of an anionic urethane resin having a polyester skeleton is formed on at least one of the front and back surfaces of the core material made of aluminum or aluminum alloy, and the corrosion-resistant base layer is baked at a temperature of 80 ° C. or higher and 200 ° C. or lower. A corrosion-resistant layer is formed, and a hydrophilic base layer made of an acrylic resin containing a polymer mainly composed of polyoxyethylene chains is laminated on the corrosion-resistant layer to obtain a laminated coating film, followed by washing with water or hot water. The surface portion of the hydrophilic base layer is partly removed thereby, and the residual portion after the partial removal is a hydrophilic layer adjusted to a water content of 0.01 mg / dm ² or more and 0.2 mg / dm ² or less. The manufacturing method of the fin material for air conditioning for indoor units which has the low odor and low water-containing function. By removing the surface of the hydrophilic base layer by the water washing or hot water washing, and the remaining amount of the film after the water washing or hot water washing is 40% or more and 70% or less by weight difference with respect to the water washing or before water washing. The air conditioning fin material for indoor units having a low odor and low water content function according to claim 4, wherein a hydrophilic layer having a water content of 0.01 mg / dm ² or more and 0.2 mg / dm ² or less is obtained. Manufacturing method.

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