JPH05264190A - Fin material for heat exchanger made of aluminum - Google Patents

Abstract

PURPOSE:To provide a heat exchanger made of aluminum prevented from giving out an offensive odor by a method wherein fin members for the heat exchanger are provided with a hydrophilic film, containing antiseptic, on the surfaces thereof. CONSTITUTION:In a heat exchanger 10 made of aluminum, which is constituted of a meandering flat heat exchanging tube 2 having a multitude of refrigerant passages as well as headers 4, 5 attached to both ends thereof and corrugate fins 3 interposed between the straight parts 2a of the tube 2, a chromate film 6 is applied on the surfaces of the fins 3 attached to the heat exchanging tube 2 while a hydrophilic film, containing antiseptic 7, is provided on the chromate film 6. Benzoic acid or bensoates, salicylic acid or salicylates, sorbic acid and the salts thereof, para-hydroxybenzoate esters and the like are employed as the antiseptic. A film, employing alkali silicate (water glass) as a base, a film consisting of a porous substance such as silica and the like and organic high polymer and the like are employed as the hydrophilic film 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aluminum heat exchanger fin material.

[0002]

2. Description of the Related Art Conventionally, a fin of an aluminum heat exchanger used for a room cooler or the like is provided with a corrosion resistant film on the surface of an aluminum plate in order to impart corrosion resistance,
Furthermore, in order to impart hydrophilicity, a hydrophilic film was provided on the surface.

[0003]

However, such a conventional aluminum heat exchanger has a problem that an unpleasant odor is generated by the hydrophilic film.

An object of the present invention is to solve the above-mentioned problems of the prior art and to provide a fin material for a heat exchanger made of aluminum which has a fin having a hydrophilic film and has no unpleasant odor.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a fin material for a heat exchanger made of aluminum, the surface of which is provided with a hydrophilic coating containing a preservative.

When providing a hydrophilic coating on the fin material, a corrosion resistant coating made of a chromate coating is previously formed on the surface of the fin material in order to increase the corrosion resistance of the fin material and the adhesion to the hydrophilic coating. And then
It is preferable to provide a hydrophilic film on it. In addition, it is preferable to previously form a synthetic resin corrosion resistant film made of, for example, an acrylic resin on the surface of the fin material. And these anticorrosion coatings may also contain a preservative.

Examples of the hydrophilic film include a film based on alkali silicate (water glass) and a film composed of a porous material such as silica and an organic polymer. To form a film based on an alkali silicate on a fin material, an aqueous solution of an alkali silicate is applied to the surface of the fin material, and the aqueous solution of the alkali silicate is, for example, phosphate,
Cure with Glyoxal. To form a film made of a porous material and an organic polymer on a fin material, porous silica is added to an aqueous solution of an organic polymer such as a water-soluble polyolefin resin, and an aqueous solution containing this silica is added. Is applied to the surface of the fin material and dried.

As preservatives, benzoic acid or its salts, salicylic acid or its salts, sorbic acid or its salts, dehydroacetic acid or its salts, paraoxybenzoic acid esters, 2- (2-furyl) -3- (5- Nitro-2-furyl) acrylic acid amide or the like is used.

In order to form a hydrophilic coating containing a preservative on the fin material of the heat exchanger, the above-mentioned one or more preservatives are added to the surface treatment liquid for forming the hydrophilic coating. The fin treatment is applied with the surface treatment liquid added with, or the fin treatment is immersed in the surface treatment liquid added with the preservative.
The amount of the preservative added to the surface treatment solution is, for example, 0.
0005 to 1.0% by weight, preferably 0.002 to 0.
It is 1% by weight.

When the anticorrosive coating provided on the fin material of the heat exchanger contains an antiseptic agent, the above-mentioned one or more antiseptic agents are added to the surface treatment liquid for forming the anticorrosive coating. Is applied to the aluminum plate constituting the fin material, or the aluminum plate constituting the fin material is immersed in the surface treatment liquid containing the preservative.

[0011]

According to the above-mentioned aluminum heat exchanger fin material, since a hydrophilic coating containing a preservative is provided on the surface, an aluminum heat exchanger fin material having a hydrophilic coating can be obtained. By forming this fin material into the shape of a corrugated fin and combining the molded fin and the heat exchange tube, an aluminum heat exchanger having no unpleasant odor can be assembled. Since the unpleasant odor generated due to the hydrophilic film is removed at the fin material stage, the heat exchanger can be easily manufactured.

[0012]

Embodiments of the present invention will now be described with reference to the drawings.

1 and 3 show a first embodiment of the present invention.

In the figure, an aluminum heat exchanger (1
(0) is a meandering flat heat exchange tube (2) having a large number of refrigerant passages.
And a corrugated fin (3) interposed between the straight pipe portion (2a) of the heat exchange pipe (2).
Headers (4) and (5) are attached to both ends of each. The surface of the fin (3) attached to the heat exchange tube (2) is provided with a chromate film (6), on which the preservative (7) is applied.
A hydrophilic film (8) containing is provided.

Such a heat exchanger (10) is manufactured, for example, as follows.

As a material for the fins (3) of the heat exchanger (10),
A JIS A-1100H24 aluminum plate (1) having a thickness of 1 mm and a width of 50 mm was used, and the surface thereof was treated with a solution containing 2% by weight of chromic acid (Allodin manufactured by Nippon Paint Co., Ltd.) at 30 ° C. for 3 minutes, A chromate film (6) is formed on the surface of the aluminum plate (1).

Next, an aqueous solution containing 2% by weight of an alkali silicate, 0.8% by weight of glyoxal and 0.1% by weight of a preservative was applied to the surface of the chromate film (6) by the roll coating method, and then 160 By drying at 10 ° C. for 10 minutes, a hydrophilic film (8) containing a preservative (7) is formed to form the aluminum heat exchanger fin material according to the present invention.

Then, the fin material is formed into a corrugated fin shape, and the formed fin (3) and heat exchange tube (2) are formed.
Assemble the heat exchanger (10) by combining and.

FIG. 2 shows a second embodiment of the present invention.

In the figure, the fin of this second embodiment
(3) is provided with a synthetic resin corrosion-resistant coating (9) containing an antiseptic (7) on the surface of the aluminum plate (1), on which a hydrophilic coating (8) further containing an antiseptic (7) is provided. ) Is provided.

To manufacture such a heat exchanger (10),
For example, on the surface of the aluminum plate (1) similar to the above, 0.
A water-soluble acrylic resin containing 1% by weight of a preservative is applied to form a corrosion-resistant coating (9) containing a preservative (7) and having a thickness of about 1 micron, and 2% by weight of an alkali silicate is formed on the corrosion-resistant coating (9). An aqueous solution containing 0.8% by weight of glyoxal and 0.1% by weight of a preservative is applied to form a hydrophilic film (8), and the fin material for a heat exchanger made of aluminum according to the present invention is formed.

Then, this fin material is formed into the shape of a corrugated fin, and the formed fin (3) and heat exchange tube (2) are formed.
Assemble the heat exchanger (10) by combining and.

[0023]

INDUSTRIAL APPLICABILITY As described above, the aluminum heat exchanger fin material according to the present invention is provided with a hydrophilic coating containing a preservative on the surface thereof. A fin material for heat exchanger made of aluminum with no unpleasant odor was obtained, and this fin material was molded into the shape of a corrugated fin, and by combining the fin after molding and the heat exchange tube The heat exchanger can be assembled. Moreover, according to the present invention, since the unpleasant odor generated due to the hydrophilic film is removed at the stage of the fin material, there is an effect that it is easy to manufacture an aluminum heat exchanger having no unpleasant odor.

[Brief description of drawings]

FIG. 1 is an enlarged sectional view of fins of a heat exchanger according to a first embodiment of the present invention.

FIG. 2 is an enlarged sectional view showing a fin of the second embodiment.

FIG. 3 is a schematic perspective view of the heat exchanger of the first embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Aluminum plate 3 Fins 6 Corrosion resistant film consisting of chromate film 7 Antiseptic 8 Hydrophilic film 9 Synthetic resin corrosion resistant film 10 Heat exchanger

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masaaki Ito 6-224 Kaiyama-cho, Sakai City Showa Aluminum Co., Ltd.

Claims (1)

[Claims] 1. A hydrophilic film containing a preservative (7) on its surface.
(8) Aluminum fin material for heat exchangers.