JP2009178678A - Aluminum fin material for heat exchanger and fin press method using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an aluminum fin material for a heat exchanger which has an excellent lubricity even if a press lubricant oil is not supplied or an ordinary supplying amount is reduced, capable of being press-worked with controlling adhesion of aluminum to a tool and accumulation of a coated film, and has hydrophilicity remaining after the press work. <P>SOLUTION: The aluminum fin material consists of a substrate 2, a first coating film 3 formed on the surface of the substrate, and a second coating film 4 formed on the surface of the first coating film. The first coating film 3 contains a wax in a base resin consisting of one or more of a urethane resin, epoxy resin, polyester resin and phenol resin, and also the thickness of the film is 0.2-20 μm. The wax content of the first coating film 3 is 0.1-10 mass%. The wax consists of one or more of carnauba, polyethylene, nylon, polyester, fluorine resin, polypropylene, amino resin and silicon based resin. The second coating film 4 consists of a hydrophilic resin and also the thickness of the film is 0.2-5 μm. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an aluminum fin material for a heat exchanger that can be pressed without supplying press lubricant and a fin press method using the same.

  2. Description of the Related Art Conventionally, heat exchangers that operate as an evaporator or a condenser are used in air conditioners such as home air conditioners, automobile air conditioners, and packaged air conditioners, and refrigerators. And most commonly used in domestic indoor air conditioners and commercial packaged air conditioners are cross fin tube heat exchangers (plate fin tube heat exchangers). The cross fin tube which comprises this cross fin tube heat exchanger is comprised from the air side aluminum plate fin and the refrigerant | coolant side heat exchanger tube (copper pipe).

  Further, the aluminum plate fin is transmitted by dip-coating or spray-coating processing oil on the surface of the aluminum plate fin material, followed by processing (press processing) in which punching, overhanging, drawing, ironing, shearing, etc. are combined. It can be obtained by applying a fin collar for passing a heat tube or surface processing for improving the heat transfer coefficient of the surface. And the said aluminum plate fin may form various functional films, such as hydrophilic property or water repellency, by previously coating the surface with resin, a silica fine powder, water glass etc.

  In the press working, if the working oil is not applied to the surface of the aluminum plate fin material, aluminum adheres to the surface of the punching punch, overhanging punch or ironing punch. For this reason, the aluminum fin does not have a predetermined shape, or due to molding defects such as flare cracking, the adhesion between the aluminum plate fin and the heat transfer tube decreases, the performance of the heat exchanger decreases, and the mold itself Fatal problems such as damage will occur.

  As the processing oil, it is common to use a low-viscosity press oil having a kinematic viscosity of about 1 to 3 cSt having self-volatility. In the case of using such processing oil, after pressing, heat transfer tubes are passed through the aluminum plate fins, the heat transfer tubes are expanded, and the aluminum plate fins and the heat transfer tubes are fixed to form a heat exchanger. The processing oil is evaporated by exposing it to an atmosphere of 200 ° C. for about 10 minutes.

  However, various kinds of substances such as an oily agent that inhibits hydrophilicity are added to the processing oil to be used, which may cause a decrease in hydrophilic performance necessary for the aluminum fin material. In addition, there are some which swell and deteriorate the coating film resin itself coated on the aluminum fin material. When a heat exchanger is produced using such an aluminum fin material, the flow and discharge of condensed water are hindered, and the heat exchanger performance is degraded.

In addition, the above-mentioned processing oil is poor in lubricity due to low viscosity, and often causes material breakage when processing fin collars, and also tends to cause aluminum adhesion to the tool. Has also increased.
Furthermore, it is necessary to pass through a drying furnace in order to heat and heat the heat exchanger to dissipate the processed oil, increasing CO ₂ emissions related to the operation of the drying furnace, releasing volatilized oil into the atmosphere, etc. There is a problem of adversely affecting the global environment.
Thus, in the aluminum fin material used conventionally, even if it uses a low-viscosity processing oil in the case of press work, the above-mentioned problem occurs.

JP-A-6-39347 JP 7-43093 A JP-A-9-145281 Japanese Patent Laid-Open No. 10-103858 Japanese Patent Laid-Open No. 10-306997 JP 2003-287394 A JP 2005-344144 A

  The present invention has been made in view of such conventional problems, and it is possible to provide aluminum with excellent lubricity without supplying press lubricant oil or reducing the normal supply amount. An object of the present invention is to provide an aluminum fin material for a heat exchanger that can be pressed while suppressing adhesion and deposition of a coating film, and that remains hydrophilic after the pressing.

1st invention is the aluminum fin material for heat exchangers which can perform press processing, without supplying press lubricating oil or reducing normal supply amount,
The aluminum fin material comprises a substrate made of aluminum, a first coating film formed on the surface of the substrate, and a second coating film formed on the surface of the first coating film,
The first coating film contains a wax in the base resin and has a film thickness of 0.2 to 20 μm.
The base resin is composed of one or more of urethane resin, epoxy resin, polyester resin, and phenol resin,
The content of the wax in the first coating film is 0.1 to 10% (mass%, the same applies hereinafter),
The wax comprises one or more of carnauba, polyethylene, nylon, polyester, fluorine resin, polypropylene, amino resin, and silicon resin,
The second coating film is made of a hydrophilic resin and has a film thickness of 0.2 to 5 μm.

  The aluminum fin material for a heat exchanger of the present invention is provided with a first coating film having lubricity on a substrate made of aluminum, and further provided with a second coating film having hydrophilicity on the first coating film. It has a structure. As a result, even if press lubricant oil is not supplied or even when the normal supply amount is reduced, press working can be performed with excellent lubricity and suppressing adhesion of aluminum to the tool and deposition of coating film. It is possible to obtain aluminum fins for heat exchangers that are hydrophilic and hydrophilic.

  In other words, when the aluminum fin material for heat exchanger is pressed, the first coating film and the second coating film enter the friction surface. Therefore, by controlling the components and film thickness of the first coating film and the second coating film, direct contact between the tool and the material fracture surface can be prevented, and contained in the first coating film. It is possible to improve the lubricity of the friction surface by using the wax. Therefore, adhesion of aluminum to the tool can be prevented, and coating film deposition on the tool can be suppressed.

  And since the said aluminum fin material for heat exchangers has provided the hydrophilic 2nd coating film in the outermost surface, it is hydrophilic by the said 2nd coating film which remain | survives at least in parts other than a press-working part after a press process. Sex can be secured.

As described above, according to the present invention, even if the press lubricant is not supplied or the normal supply amount is reduced, the adhesion of aluminum to the tool and the deposition of the coating film are suppressed with excellent lubricity. Thus, it is possible to provide an aluminum fin material for a heat exchanger that can be pressed and remains hydrophilic after the pressing.
Furthermore, by using the aluminum fin material for heat exchangers of the present invention, it is possible to reduce the purchase cost and drying cost of press oil, and it is possible to reduce the discharge of organic substances into the atmosphere, which has an impact on the environment. Can be reduced.

  The second invention is characterized in that the fin press processing is performed without supplying fin press oil to the aluminum fin material for heat exchangers described in the first invention or by reducing the normal supply amount. The fin press method.

The fin press method uses the aluminum fin material for a heat exchanger according to the first aspect of the present invention having the above-described excellent characteristics, so that it is excellent without supplying the press lubricant or reducing the normal supply amount. Due to the lubricity, press working can be performed while suppressing adhesion of aluminum to the tool and deposition of the coating film, and an aluminum fin for a heat exchanger having hydrophilicity can be obtained.
In addition, since the above-mentioned fin press method performs press processing without using or reducing press oil, it is possible to reduce the purchase cost and drying cost of the press oil, and to reduce the discharge of organic substances into the atmosphere. Can reduce the environmental impact.

As described above, the first coating film of the aluminum fin material for a heat exchanger according to the first aspect of the present invention contains a wax in the base resin and has a film thickness of 0.2 to 20 μm.
When the film thickness of the first coating film is less than 0.2 μm, there is a problem that the lubricity by the first coating film cannot be sufficiently obtained. On the other hand, when the film thickness exceeds 20 μm, there is a problem that the coating film is brittle and easily peels off, and is deposited on the mold, thereby hindering press working. Moreover, at the time of painting, it accumulates on a painting roll etc., and production becomes difficult.

  In addition, as described above, the wax contained in the first coating film may be used alone from among carnauba, polyethylene, nylon, polyester, fluorine resin, polypropylene, amino resin, and silicon resin. Two or more kinds may be mixed and used.

Moreover, the said base resin consists of 1 type (s) or 2 or more types among urethane type resin, an epoxy resin, a polyester resin, and a phenol resin.
Resins constituting these base resins are suitable as base resins because they have the property of good adhesion to the second coating film.

Moreover, content of the said wax in a said 1st coating film is 0.1 to 10%.
When the content of the wax is less than 0.1%, there is a problem that the first coating film cannot have sufficient lubricity. On the other hand, when the content of the wax exceeds 10%, the adhesion with the second coating film is hindered, and the problem is that the coating film is deposited on the mold. There is a problem that production becomes difficult.

The second coating film of the aluminum fin material is made of a hydrophilic resin and has a thickness of 0.2 to 5 μm.
Moreover, when the film thickness of the said 2nd coating film is less than 0.2 micrometer, there exists a problem that the hydrophilicity by the said 2nd coating film cannot fully be obtained. On the other hand, when the film thickness of the second coating film exceeds 5 μm, there is a problem that the coating film is brittle and easily peels off and accumulates on the mold, thereby hindering press working. Moreover, at the time of painting, it accumulates on a painting roll etc., and production becomes difficult.
Moreover, as hydrophilic resin which comprises the said 2nd coating film, polyvinyl alcohol, an acrylic resin, a cellulose resin etc. are mentioned, for example.

  Moreover, the said 1st coating film and the 2nd coating film can be formed by apply | coating a coating material on the surface by a roll coater method, a bar coater method, etc., and performing a heat processing after that, for example.

The second coating film may also contain wax. In this case, the lubricity during press working can be further improved, and even if the friction conditions such as high-strength materials and high-temperature atmosphere are more severe, fin press work without supplying press oil It can be performed.
When the wax is contained in the second coating film, it is preferable to employ a fluororesin or polyethylene as the wax so that the hydrophilicity of the second coating film does not decrease.

It is preferable that the hydrophilic resin of the second coating film of the aluminum fin material for a heat exchanger contains one or more of fluorine-based resin and polyethylene resin.
In this case, the lubricity during press working can be improved.

The second coating film has a particle diameter of 0.1 to 30 μm and 1 to 3 times the thickness of the second coating film. It is preferable to contain 1-20 weight part (Claim 3).
In this case, when performing the press work, the frictional resistance can be reduced on the friction surface between the aluminum fin material and the tool, and the ironing workability and the overhang workability can be improved.

  When the particle size of the resin beads is less than 0.1 μm, the effect on the friction surface is not exhibited because it is too fine. On the other hand, if the particle size exceeds 30 μm, the frictional surface will drop more, or it will fall off by rubbing with the mold, resulting in loss of lubricity effect, and depositing at each location, There is a risk of adverse effects.

  Moreover, when the content of the resin beads is less than 0.1 parts by weight with respect to 100 parts by weight of the hydrophilic resin, the above effect cannot be obtained sufficiently. On the other hand, when the content of the resin beads exceeds 20 parts by weight with respect to 100 parts by weight of the hydrophilic resin, dropping from the coating film increases, and coating film powder may be deposited on the mold surface. There is a risk of damaging the product and cost.

Moreover, it is preferable that the hydrophilic resin of the said 2nd coating film contains the organic resin containing 1 type, or 2 or more types among a hydroxyl group, a carboxyl group, an ester group, and an ether group (Claim 4).
In this case, the hydrophilicity is good, and the deterioration of the heat exchanger performance can be suppressed.
Moreover, when containing the said organic resin, you may contain only organic resin or what added surfactant etc. to the said organic resin.

Moreover, it is preferable that the said 2nd coating film contains a silicate and / or colloidal silica further (Claim 5).
In this case, excellent hydrophilicity can be further imparted to the hydrophilic film.

Further, it is preferable that a hydrophilic lubricating film made of a water-soluble polyether having a molecular weight of 4000 to 400,000 is further formed on the surface of the second coating film.
Since the hydrophilic lubricating film is made of a water-soluble polyether having a molecular weight of 4000 to 400,000, the lubricity during press working can be further improved, and can be easily removed with water, and The hydrophilicity of the second coating film is not inhibited after the removal.

  When the molecular weight of the water-soluble polyether is less than 4000, there is a risk that coating powder accumulates on the mold surface during press processing, or the lubricating coating of the material after coating becomes low due to the low melting point of the lubricating coating. May be easily fused, and the materials after coating may stick to each other and workability may be reduced. On the other hand, when the molecular weight of the water-soluble polyether exceeds 400000, the cost may increase, and there may be a problem in handling and mass productivity.

  The polyether can be obtained, for example, by polymerizing alkylene oxide and replacing the hydroxyl group with an alkyl group, alkenyl group, alkynyl group or the like. Specific examples of the alkylene oxide constituting the polyether include ethylene oxide, propylene oxide, 1,2-epoxybutane (α-butylene oxide), 2,3-epoxybutane (β-butylene oxide), Examples include 1,2-epoxy-1-methylpropane and 1,2-epoxyheptane.

  The polymerization form of the alkylene oxide is not particularly limited, and may be homopolymerization of one type of alkylene oxide, random copolymerization of two or more types of alkylene oxide, block copolymerization, random / block copolymerization, or the like. .

  The water-soluble polyether is a polyether comprising one or more of polyalkylene glycol, polyalkylene glycol alkyl ether, polyalkylene glycol aryl ether, aliphatic polyalkylene glycol ester, and aliphatic polyalkylene glycol sorbitan ester. In addition, it is preferable that the polyether is one or two or more selected from polymers obtained by one or more urethane bonds among the polyethers (claim 7).

  Polymers by urethane bonds of the above polyether are one or more of polyalkylene glycol, polyalkylene glycol alkyl ether, polyalkylene glycol aryl ether, aliphatic polyalkylene glycol ester, aliphatic polyalkylene glycol sorbitan ester. It can be obtained by reacting with isocyanate.

The hydrophilic lubricating film preferably has a thickness of 10 to 200 mg / m ² .
When the thickness of the hydrophilic lubricating film is less than 10 mg / m ² , the above effects may not be sufficiently obtained. On the other hand, when the film thickness exceeds 200 mg / m ² , the coating film is brittle and easily peels off, and is deposited on the mold, which may hinder press working. In addition, at the time of painting, there is a possibility that it may be deposited on a painting roll or the like and production may become difficult.

  In addition, the hydrophilic lubricating film is H.264. L. B. Is an alkylene oxide adduct of a monohydric or higher alcohol in the range of 3 to 20, a hydrocarbyl ether of an alkylene oxide adduct of a monohydric or higher alcohol, a fatty acid ester of an alkylene oxide adduct of a monohydric or higher alcohol, or a carboxylic acid 1. Lubricating additive comprising one or more of salts, alkyl sulfonates, alkyl sulfates, alkyl phosphates, and fatty acid alkanolamides, with the total solid content of the hydrophilic lubricating film as 100%. It is preferable to contain 0 to 50% (claim 9).

  H. of the above lubricating additive. L. B. Is less than 3, there is a problem that the lubricating additive is easily separated and separated. H. L. B. (Hydrophile-Lipophile Balance) is a value representing the degree of affinity of a surfactant for water and oil (an organic compound insoluble in water).

  Alcohol oxide adduct of monohydric or higher alcohol, hydrocarbyl ether of alkylene oxide adduct of monohydric or higher alcohol, alcohol constituting fatty acid ester of alkylene oxide adduct of monohydric or higher alcohol, Have six.

Examples of such alcohols include monovalent alcohols having 8 to 23 carbon atoms, and may have a molecular chain, an unsaturated bond, or a cyclic structure in the molecule. Specific examples include octanol, nonanol, decanol, undecanol, dodecanol, tridecanol, tetradecanol, pentadecanol, hexadecanol, heptadecanol, octadecanol, nonadecanol, eicosanol, ethylphenol, nonylphenol, and the like. These may be used alone or as a mixture thereof. Further, if it is divalent or more, neopentyl glycol, trimethylol ethane, trimethylol propane, trimethylol butane, pentaerythritol, dipentaerythritol, 2-butyl-2-ethyl-1,3-propanediol, 2 -Methyl-2-propyl-1,3-propanediol, 2,2-diethyl-1,3-propanediol and the like.
Further, from the viewpoint of lubricity and water removability, the alcohol preferably has 12 to 18 carbon atoms.

  Further, the alkylene oxide adduct of the above-mentioned monovalent or higher alcohol alkylene oxide adduct, the hydrocarbyl ether of the monovalent or higher alcohol alkylene oxide adduct, the fatty acid ester of the monovalent or higher alcohol alkylene oxide adduct, It is preferable to obtain by addition polymerization of a C 2-6 alkylene oxide, and it is more preferable to carry out addition polymerization of a C 2-4 alkylene oxide.

Specific examples of the alkylene oxide having 2 to 6 carbon atoms include ethylene oxide, propylene oxide, 1,2-epoxybutane (α-butylene oxide), and 2,3-epoxybutane (β-butylene oxide). 1,2-epoxy-1-methylpropane, 1,2-epoxyheptane and the like.
The polymerization form of alkylene oxide or the like is not particularly limited, and may be homopolymerization of one type of alkylene oxide, random copolymerization of two or more types of alkylene oxide, block copolymerization, random / block copolymerization, or the like.
Moreover, when adding an alkylene oxide to the polyhydric alcohol which has 2-6 hydroxyl groups, you may add to all the hydroxyl groups, and you may add only to a part of hydroxyl groups.

  Alkylene oxide adduct of monohydric or higher alcohol, hydrocarbyl ether of alkylene oxide adduct of monohydric or higher alcohol, terminal hydroxyl group of alkylene oxide adduct constituting fatty acid ester of alkylene oxide adduct of monohydric or higher alcohol A part or all of the above can be hydrocarbyl etherified.

Here, the hydrocarbyl group is a hydrocarbon group having 1 to 24 carbon atoms.
Examples of the hydrocarbon group include an alkyl group, an alkenyl group, a cycloalkyl group, an alkylcycloalkyl group, an aryl group, an alkylaryl group, and an arylalkyl group.

  Examples of the alkyl group having 1 to 24 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, straight chain or branched Pentyl group, linear or branched hexyl group, linear or branched heptyl group, linear or branched octyl group, linear or branched nonyl group, linear or branched decyl group, straight Chain or branched undecyl group, linear or branched dodecyl group, linear or branched tridecyl group, linear or branched tetradecyl group, linear or branched pentadecyl group, linear or branched Hexadecyl group, linear or branched heptadecyl group, linear or branched octadecyl group, linear or branched nonadecyl group, linear or branched icosyl group, linear or branched heicosyl group, linear Or a branched docosyl group, linear or branched There tricosyl group, and Tetoraikoshiru group of straight or branched is.

  Examples of the alkenyl group having 2 to 24 carbon atoms include a vinyl group, a linear or branched propenyl group, a linear or branched butenyl group, a linear or branched pentenyl group, and a linear or branched hexenyl group. Group, linear or branched heptenyl group, linear or branched octenyl group, linear or branched nonenyl group, linear or branched decenyl group, linear or branched undecenyl group, linear or Branched dodecenyl group, linear or branched tridecenyl group, linear or branched tetradecenyl group, linear or branched pentadecenyl group, linear or branched hexadecenyl group, linear or branched heptadecenyl group A linear or branched octadecenyl group, a linear or branched nonadecenyl group, a linear or branched icosenyl group, a linear or branched henicosyl group, a linear or branched dococenyl group, a linear or branched group Branch tricocenyl , And there is a tetracosenyl group of straight or branched.

Examples of the cycloalkyl group having 5 to 7 carbon atoms include a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group.
Examples of the alkylcycloalkyl group having 6 to 11 carbon atoms include a methylcyclopentyl group, a dimethylcyclopentyl group (including all structural isomers), a methylethylcyclopentyl group (including all structural isomers), a diethylcyclopentyl group ( Including all structural isomers), methylcyclohexyl group, dimethylcyclohexyl group (including all structural isomers), methylethylcyclohexyl group (including all structural isomers), diethylcyclohexyl group (including all structural isomers) Including), methylcycloheptyl group, dimethylcycloheptyl group (including all structural isomers), methylethylcycloheptyl group (including all structural isomers), and diethylcycloheptyl group (including all structural isomers) ) Etc.

  Examples of the aryl group having 6 to 10 carbon atoms include a phenyl group and a naphthyl group.

  Examples of the alkylaryl group having 7 to 18 carbon atoms include a tolyl group (including all structural isomers), a xylyl group (including all structural isomers), and an ethylphenyl group (including all structural isomers). , Linear or branched propylphenyl group (including all structural isomers), linear or branched butylphenyl group (including all structural isomers), linear or branched pentylphenyl group (all ), Linear or branched hexylphenyl group (including all structural isomers), linear or branched heptylphenyl group (including all structural isomers), linear or branched Branched octylphenyl groups (including all structural isomers), linear or branched nonylphenyl groups (including all structural isomers), linear or branched decylphenyl groups (including all structural isomers) ), Straight or branched unde Butylphenyl (including all structural isomers) group, and (including all structural isomers) linear or branched dodecylphenyl group and the like.

  Examples of the arylalkyl group having 7 to 12 carbon atoms include benzyl group, phenylethyl group, phenylpropyl group (including propyl group isomers), phenylbutyl group (including butyl group isomers), and phenylpentyl group. (Including isomers of pentyl group), phenylhexyl group (including isomers of hexyl group), and the like.

  As the fatty acid ester of the above alkylene oxide adduct of monohydric or higher alcohol and the hydrocarbyl ether thereof, any of linear saturated fatty acid, branched saturated fatty acid, linear unsaturated fatty acid, branched unsaturated fatty acid is used. May be. In terms of carbon number, those having 7 to 22 carbon atoms are preferred. Specifically, for example, caprylic acid, pelargonic acid, capric acid, methyl laurate, myristic acid, palmitic acid, stearic acid, oleic acid, eicosane An acid etc. are mentioned.

  Examples of the carboxylate include polyoxyethylene / alkyl ether / carboxylate, N-acyl sarcosine, N-acyl glutamate, and the like. Examples of the cationic counter ion forming the salt include metal ions such as alkali metal (sodium, potassium, lithium, etc.) ions, alkaline earth metal (magnesium, calcium, barium, etc.) ions, ammonium ions, and the like.

  Examples of the alkyl sulfonate include dialkyl sulfo-succinate, alkane sulfonate, alpha olefin sulfonate, linear alkyl benzene sulfonate, molecular chain alkyl benzene sulfonate, naphthalene sulfonate- Examples include formaldehyde condensates, alkyl naphthalene sulfonates, N-methyl-N-acyl taurines, and the like. Examples of the cationic counter ion forming the salt include metal ions such as alkali metal (sodium, potassium, lithium, etc.) ions, alkaline earth metal (magnesium, calcium, barium, etc.) ions, ammonium ions, and the like.

  Examples of the alkyl sulfate include polyoxyethylene / alkyl ether / sulfate, oil and fat sulfate ester salt, and the like. Examples of the cationic counter ion forming the salt include metal ions such as alkali metal (sodium, potassium, lithium, etc.) ions, alkaline earth metal (magnesium, calcium, barium, etc.) ions, ammonium ions, and the like.

  Examples of the phosphate include alkyl phosphate, polyoxyethylene / alkyl ether / phosphate, polyoxyethylene / alkyl phenyl ether / phosphate, and the like. Examples of the cationic counter ion forming the salt include metal ions such as alkali metal (sodium, potassium, lithium, etc.) ions, alkaline earth metal (magnesium, calcium, barium, etc.) ions, ammonium ions, and the like.

Further, as described above, the lubricating additive is preferably contained in an amount of 1.0 to 50% based on 100% of the entire solid content of the hydrophilic lubricating film.
In this case, the lubricity during press working can be further improved.
When the content of the lubricating additive is less than 1.0% with the total solid content of the hydrophilic lubricating coating as 100%, there is a possibility that the lubricity improving effect by the lubricating additive cannot be sufficiently obtained. . On the other hand, when the content of the lubricating additive exceeds 50%, the lubricating coating film tends to cohesively break down, so that the coating film may be deposited on the mold during press processing, There is a risk of accumulation and difficulty in production.

Moreover, it is preferable that the base layer which consists of a chemical conversion film or a corrosion-resistant resin film is formed in the surface of the board | substrate of the said aluminum fin material for heat exchangers (Claim 10).
When the base layer which consists of the said chemical conversion film is formed, the adhesiveness of an aluminum plate and a precoat coating film can be improved effectively. In addition, excellent corrosion resistance has been realized, and corrosion under the coating caused when corrosive substances such as water and chlorine compounds have permeated the surface of the aluminum plate is suppressed. You can plan.

In addition, as the chemical conversion film, chemical treatment such as chromate treatment such as phosphate chromate and chromate chromate, non-chromate treatment with titanium phosphate other than chromium compounds, zirconium phosphate, molybdenum phosphate, zinc phosphate, zirconium oxide, etc. A film obtained by film treatment, so-called chemical conversion treatment, is employed.
The chemical conversion treatment methods such as chromate treatment and non-chromate treatment include a reaction type and a coating type, but any method may be adopted in the present invention.

When a base layer made of the above corrosion-resistant resin film is provided, excellent corrosion resistance is realized, and corrosion under the coating caused when corrosive substances such as water and chlorine compounds penetrate the surface of the aluminum fin material. Is suppressed, and it is possible to prevent coating film cracking and coating film peeling.
Moreover, as said corrosion-resistant resin film, the film | membrane which consists of an epoxy resin, a urethane resin, a polyester resin etc. is mentioned, for example.

Example 1
In this example, an example of an aluminum fin material for a heat exchanger according to the present invention will be described with reference to FIGS.
In this example, aluminum fin materials for heat exchangers (samples e1 to e54) shown in Tables 1 to 3 are prepared as examples according to the present invention, and heats shown in Table 4 as comparative examples according to the present invention. An aluminum fin material for the exchanger (sample c1 to sample c12) was produced. The configuration of sample e1 to sample e29 and sample c1 to sample c8 is shown in FIG. 1, and the configuration of sample e30 to sample e54 and sample c9 to sample c12 is shown in FIG.

As shown in FIGS. 1 and 2, the aluminum fin material for heat exchanger 1 (sample e1 to sample e54) of the present example is at least a first coating film 3 and the first coating with respect to a substrate 2 made of aluminum. The second coating film formed on the surface of the coating film 3 is formed.
This will be described in detail below.

First, as the substrate 2, an aluminum plate having A1050-H26 and a thickness of 0.100 mm was prepared.
Further, the following materials for forming the first coating film 3, the second coating film 4, and the hydrophilic lubricating film 6 described later were prepared.
(First coating)
As base resin which comprises a 1st coating film, the following A1-A5 was prepared.
A1: Urethane resin.
A2: Epoxy resin.
A3: Polyester resin.
A4: Phenolic resin.
A5: Urethane resin.
The following B1 to B8 were prepared as waxes constituting the first coating film.
B1: Carnauba.
B2: Polyethylene.
B3: Nylon.
B4: Polyester.
B5: Fluorine.
B6: Polypropylene.
B7: Amino resin.
B8: Silicon resin.

(Second coating film)
The following C1 to C6 were prepared as hydrophilic paints constituting the second coating film.
C1: Water glass hydrophilic paint,
10 parts by weight of alkali silicate (SiO ₂ : Na ₂ O = 3: 5), ₂ parts by weight of hydroxyethyl acrylate-acrylic acid copolymer, 0.5 part by weight of ammonium carbonate zirconium salt.
C2: Resin-based hydrophilic paint + silica-based hydrophilic paint,
70 parts by weight of acrylic resin, 15 parts by weight of melamine resin, 10 parts by weight of polyoxyethylene alkylphenyl ether (surfactant), 5 parts by weight of colloidal silica.
C3: resin-based hydrophilic paint,
10 parts by weight of hydroxyethyl cellulose (water-soluble cellulose resin), 10 parts by weight of an acrylic acid-acrylamide copolymer (water-soluble acrylic resin).
C4: resin-based hydrophilic paint,
2-acrylamido-2-methylpropanesulfonic acid 20 parts by weight, methacrylic acid 60 parts by weight, methyl methacrylate 15 parts by weight, dimethylaminoethyl methacrylate 5 parts by weight.
C5: resin-based hydrophilic paint,
25 parts by weight of sodium salt of carboxymethylcellulose, 50 parts by weight of ammonium salt of carboxymethylcellulose, 25 parts by weight of N-methylolacrylamide, 5 parts by weight of sodium alkyldiphenyl ether disulfonate (surfactant).
C6: resin-based hydrophilic paint,
Polyvinyl alcohol 50 parts by weight, carboxymethylcellulose 50 parts by weight, zirconium chelate compound 5 parts by weight, dialkylsulfosuccinic acid ester salt (surfactant) 5 parts by weight.
Moreover, the following D1 and D2 were prepared as resin beads to be contained in the second coating film.
D1: Fluorine type.
D2: Polyethylene.

(Hydrophilic lubricant film)
The following E1 to E5 were prepared as water-soluble polyethers constituting a hydrophilic lubricating film described later.
E1: Polyalkylene glycol.
E2: polyalkylene glycol alkyl ether.
E3: polyalkylene glycol aryl ether.
E4: Aliphatic polyalkylene glycol ester.
E5: Aliphatic polyalkylene glycol sorbitan ester.
Further, the following F1 to F8 were prepared as lubricating additives to be added to the hydrophilic lubricating film.
F1: Alkylene oxide adduct.
F2: Hydrocarbyl ether.
F3: fatty acid ester.
F4: carboxylate.
F5: alkyl sulfonate.
F6: Alkyl sulfate ester salt.
F7: Alkyl phosphate.
F8: fatty acid alkanolamide.

Next, a method for producing the aluminum fin material for the heat exchanger (samples e1 to e54 and samples c1 to c12) will be described.
First, the substrate 2 is degreased with a commercially available weak alkaline degreasing agent, and then a liquid composed of chromic acid, phosphoric acid and hydrofluoric acid, and a liquid composed of phosphoric acid and hydrofluoric acid. The base layer 5 made of a chemical conversion film mainly composed of phosphoric acid chromate was formed. The amount of chromium in the chemical conversion film was 20 mg / m ² .

  Next, the coating composition which mixed and mixed the base resin and wax for said 1st coating films with the kind and content which are shown to Table 1-Table 4 with respect to the board | substrate 2 was coated using the roll coater. Then, baking and hardening were performed by performing a heat treatment at 200 ° C. for 20 seconds to form a first coating film 3 having a film thickness shown in Tables 1 to 4.

  Then, the coating composition which mixed the hydrophilic resin and resin beads for said 2nd coating films with the kind and content which are shown in Table 1-Table 3 on the surface of the said 1st coating film 3, and mixed was roll-coater. It apply | coated by the method, Then, the heat processing for 120 degreeC x 30 second was performed, and the 2nd coating film 4 which has the film thickness shown in Table 1-Table 4 was formed. In addition, the film thickness of the 2nd coating film shown to a table | surface is a film thickness of the part which consists only of hydrophilic resin in which the resin bead does not exist.

Further, as to sample e30 to sample e54 and sample c9 to sample c12, as shown in FIG. 2, the water-soluble polyether and the lubricant additive for the hydrophilic lubricating film are formed on the surface of the second coating film 4. Coating compositions prepared by combining the types and contents shown in Tables 1 to 4 were mixed by a roll coater method, and then subjected to a heat treatment at 120 ° C. for 30 seconds to form films shown in Tables 2 to 4 A hydrophilic lubricating film 6 having a thickness was formed.
In Tables 1 to 4, the content of the wax, resin beads, and lubricant additive is the content (% by mass) when the total solid content of the paint is 100% by mass.

  As is known from Tables 1 to 3, the samples e1 to e54 as examples are such that the first coating film 3 contains a wax in the base resin and has a film thickness of 0.2 to 20 μm. The base resin comprises one or more of urethane resin, epoxy resin, polyester resin, and phenol resin, and the content of the wax in the first coating film is 0.1 to 10%, It can be seen that the wax is composed of one or more of carnauba, polyethylene, nylon, polyester, fluorine resin, polypropylene, amino resin, and silicon resin. Moreover, while the said 2nd coating film 4 consists of hydrophilic resins, it turns out that a film thickness is 0.2-5 micrometers.

Next, for the obtained aluminum fin materials for heat exchangers (samples e1 to e54 and samples c1 to c12), the adhesion of aluminum to the tool when pressed without using press oil, The coating deposition was evaluated.
First, the aluminum fin material was pressed using a 9.52 mmφ drawless mold (manufactured by Hidaka Machine Co., Ltd.). Table 5 shows the press working conditions. The processing speed was 250 spm, and the number of evaluation shots was 20000.

凝着性は、評価点が１０〜９点の場合を評価◎とし、評価点が８〜６点の場合を評価○とし、評価点が５〜０点の場合を評価×とし、評価が◎及び○の場合を合格、評価が×の場合を不合格とした。結果を表６〜表８に示す。 <Adhesiveness>
The adhesion was evaluated using the following formula from the aluminum adhesion area on the piercing punch surface and the second ironing punch surface after 20000 shots of pressing.

The adhesion is evaluated as ◎ when the evaluation score is 10 to 9, ９ when the evaluation score is 8 to 6 and × when the evaluation score is 5 to 0. And the case of (circle) was set as the pass, and the case where evaluation was x was set as the failure. The results are shown in Tables 6-8.

<Coating deposition>
For coating film deposition, the surface of the mold was visually observed after performing 20000 shots of press working, and the case where deposition of coating film powder was not confirmed was accepted (evaluation ○), and deposition of coating film powder was observed. The case was determined to be rejected (evaluation x). The results are shown in Tables 6-8.

As can be seen from Tables 6 and 7, Samples e1 to e54 as examples showed good results in both items of adhesion and coating deposition.
Moreover, when the 2nd coating film contains the resin bead within the preferable range of this invention, it turns out that an especially excellent result is shown in the item of adhesiveness.
Moreover, it confirmed that parts other than a press work part have hydrophilicity after press work.

  As a result, according to the present invention, even if the press lubricant is not supplied or the normal supply amount is reduced, the adhesion of aluminum to the tool and the deposition of the coating film are suppressed with excellent lubricity. It can be seen that it is possible to provide an aluminum fin material for a heat exchanger that can be pressed and remains hydrophilic after pressing.

Further, as can be seen from Table 8, the sample c1 as a comparative example has a film thickness of the first coating film lower than the lower limit of the present invention, so that sufficient lubricity cannot be obtained, and the adhesion is unacceptable. Met.
Moreover, since the film thickness of the 1st coating film exceeded the upper limit of this invention and the coating film was weak and it was easy to peel, the sample c2 as a comparative example was unsuccessful in adhesiveness and coating film deposition.

Moreover, since the content of the wax of the 1st coating film was less than the minimum of this invention, the sample c3 as a comparative example was not able to acquire sufficient lubricity, but the adhesiveness was disqualified.
Moreover, since the content of the wax of the 1st coating film exceeded the upper limit of this invention, and sample c4 as a comparative example had bad adhesiveness with a 2nd coating film, coating film deposition was disqualified.

Moreover, since the film thickness of the 2nd coating film was less than the minimum of this invention, the sample c5 as a comparative example was unable to prevent contact with an aluminum fin material and a tool, and adhesiveness was disqualified. .
Moreover, as for the sample c6 as a comparative example, the film thickness of the second coating film exceeded the upper limit of the present invention, the coating film was brittle and easily peeled off, and the coating film deposition was unacceptable.

Further, in sample c7 as a comparative example, the particle diameter of the resin beads of the second coating film exceeded the upper limit of the preferred range of the present invention, and the beads were dropped from the coating film, so the coating film deposition was unacceptable.
Further, in the sample c8 as a comparative example, the content of the resin beads of the second coating film exceeded the upper limit of the preferred range of the present invention, and the beads were dropped from the coating film, so the coating film deposition was unacceptable.

Further, the sample c9 as a comparative example has a hydrophilic lubricating film made of a hydrophilic paint for aluminum made of a water-soluble polyether having a molecular weight lower than the lower limit of the preferred range of the present invention. Was deposited on the mold surface, and the coating deposition was unacceptable.
Further, Sample c10 as a comparative example had a film thickness of the hydrophilic lubricating film exceeding the upper limit of the preferred range of the present invention, and the coating film was brittle and easily peeled.

In addition, sample c11 as a comparative example is a lubricant additive H.H. L. Since B was lower than the lower limit of the preferred range of the present invention, the lubricant additive was easily precipitated and separated, and the lubrication effect was insufficient.
Further, the sample c12 as a comparative example has a content of the lubricating additive in the hydrophilic lubricating film that exceeds the upper limit of the preferred range of the present invention, and the lubricating coating film tends to cohesively break, so that the coating film deposition fails. Met.

Explanatory drawing which shows the aluminum fin material for heat exchangers in Example 1. FIG. Explanatory drawing which shows the aluminum fin material for heat exchangers in Example 1. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Aluminum fin material for heat exchangers 2 Board | substrate 3 1st coating film 4 2nd coating film

Claims (11)

It is an aluminum fin material for a heat exchanger that can perform press processing without supplying press lubricant or reducing the normal supply amount,
The aluminum fin material comprises a substrate made of aluminum, a first coating film formed on the surface of the substrate, and a second coating film formed on the surface of the first coating film,
The first coating film contains a wax in the base resin and has a film thickness of 0.2 to 20 μm.
The base resin is composed of one or more of urethane resin, epoxy resin, polyester resin, and phenol resin,
The content of the wax in the first coating film is 0.1 to 10% (mass%, the same applies hereinafter),
The wax comprises one or more of carnauba, polyethylene, nylon, polyester, fluorine resin, polypropylene, amino resin, and silicon resin,
The said 2nd coating film consists of hydrophilic resin, and a film thickness is 0.2-5 micrometers, The aluminum fin material for heat exchangers characterized by the above-mentioned.   2. The aluminum fin material for a heat exchanger according to claim 1, wherein the hydrophilic resin of the second coating film contains one or more of fluorine-based resin and polyethylene resin.   3. The hydrophilic resin according to claim 1 or 2, wherein the second coating film comprises resin beads having a particle size of 0.1 to 30 [mu] m and 1 to 3 times the thickness of the second coating film. The aluminum fin material for heat exchangers is contained in an amount of 0.1 to 20 parts by weight with respect to parts.   In any 1 item | term of Claims 1-3, The hydrophilic resin of the said 2nd coating film contains the organic resin containing 1 type, or 2 or more types among a hydroxyl group, a carboxyl group, an ester group, and an ether group. Features aluminum fin material for heat exchangers.   The aluminum fin material for a heat exchanger according to any one of claims 1 to 4, wherein the second coating film further contains silicate and / or colloidal silica.   The heat exchange according to any one of claims 1 to 5, wherein a hydrophilic lubricating film made of a water-soluble polyether having a molecular weight of 4000 to 400,000 is further formed on the surface of the second coating film. Aluminum fin material for dexterity.   7. The water-soluble polyether according to claim 6, wherein the water-soluble polyether is one or more of polyalkylene glycol, polyalkylene glycol alkyl ether, polyalkylene glycol aryl ether, aliphatic polyalkylene glycol ester, and aliphatic polyalkylene glycol sorbitan ester. An aluminum fin material for a heat exchanger, which is one or two or more selected from polyethers obtained by polymerization and polymers obtained by one or more urethane bonds among the polyethers. According to claim 6 or 7, the hydrophilic lubricating layer is heat exchanger aluminum fin stock, wherein the film thickness of 10 to 200 mg / m ^2.   9. The hydrophilic lubricating film according to claim 6, wherein the hydrophilic lubricating film is H.264. L. B. Is an alkylene oxide adduct of a monohydric or higher alcohol in the range of 3 to 20, a hydrocarbyl ether of an alkylene oxide adduct of a monohydric or higher alcohol, a fatty acid ester of an alkylene oxide adduct of a monohydric or higher alcohol, or a carboxylic acid 1. Lubricating additive comprising one or more of salts, alkyl sulfonates, alkyl sulfates, alkyl phosphates, and fatty acid alkanolamides, with the total solid content of the hydrophilic lubricating film as 100%. An aluminum fin material for heat exchangers, containing 0 to 50%. The aluminum fin material for a heat exchanger according to any one of claims 1 to 9, wherein a base layer made of a chemical conversion film or a corrosion-resistant resin film is formed on the surface of the substrate.   The aluminum fin material for a heat exchanger according to any one of claims 1 to 10, wherein fin press processing is performed without supplying fin press oil or reducing a normal supply amount. Fin press method to do.

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