JPH04328123A - Hydrophilization treatment composition and hydrophilization treatment process - Google Patents

Abstract

PURPOSE:To provide a composition containing a specific OH-containing polyester resin and a curing agent as a curable resin composition, having excellent workability, durability of the hydrophilic nature, antibacterial property and activity to prevent the generation of ill odor and useful as a heat-exchanger of an air-conditioner, etc. CONSTITUTION:This composition contains a curable resin composition consisting of (A) an OH-containing polyester resin (preferably having an average molecular weight of 1,000-15,000) and produced by using a mixture of mono- or polyether polyols containing two hydroxyl groups in one molecule and >=3 hydroxyl groups in one molecule as a polyhydric alcohol component and a 1-7C aliphatic dibasic acid as a polybasic acid component and (B) a curing agent such as a melamine resin. The amounts of the components A and B are preferably 95-70wt.% and 5-30wt.% based on 100wt.% of A+B, respectively. Formation of bridge with water-drop can be prevented by applying the composition to heat-exchanger fins made of aluminum.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydrophilic treatment composition and a hydrophilic treatment method.

0002

[Prior art and its problems] In the heat exchanger of an air conditioner, condensed water generated during cooling becomes water droplets and forms water bridges between the fins, narrowing the air ventilation path and increasing ventilation resistance, resulting in power dissipation. Problems such as loss of energy, generation of noise, and scattering of water droplets may occur. As a measure to prevent this phenomenon, the surface of aluminum fins (hereinafter referred to as fins) is made hydrophilic to prevent the formation of water droplets and bridges caused by water droplets.

[0003] As a method for making the surface of a heat exchanger hydrophilic, 1) forming fins from an aluminum plate, assembling the fins, and then immersing them in a surface treatment agent (hydrophilic, anti-rust); , the so-called after-coat method, in which the coating is applied by means such as spraying or showering; and the so-called pre-coat method, in which a surface treatment film is formed on an aluminum plate in advance by means such as a roll coater, and then the plate is press-molded to create fins. There are two methods of law.

[0004] Regarding the former (2), methods for making the surface of the fins hydrophilic have been put to practical use: (1) a method of coating water glass represented by the general formula mSiO2/nNa2O (for example, Japanese Patent Application Laid-Open No. 1983-1993); Publication No. 13078, etc.)
(2) A method of forming a resin film by applying a solution mainly composed of an organic polymer resin such as a water-soluble polyamide resin (
For example, Japanese Patent Application Laid-Open No. 61-250495), (3)
Examples include a method of applying an aqueous resin solution made by neutralizing polycarboxylic acid resin with a basic neutralizing agent, but even though these techniques have been put into practical use, they are not fully satisfactory, and the treated board There are still problems to be improved in terms of sustainability of hydrophilicity (water droplet contact angle, whole surface water wettability), corrosion resistance, odor, press workability, and stability of treatment liquid. For example, when looking at water glass (1) above, which exhibits good hydrophilicity with a water droplet contact angle of 20 degrees or less, the treated film surface of fins treated with this material becomes powdery over time, and ventilation Occasionally, it scatters and produces a cement or chemical odor. In addition, water glass is hydrolyzed by condensed water generated during operation of the heat exchanger, making the fin surface alkaline, which makes pitting corrosion more likely to occur, and aluminum hydroxide powder (white powder), which is a corrosion product, scatters. It is known that there are environmental conservation issues. On the other hand, in the method (2) using a treatment agent, the water resistance of the film is not sufficient and the film is easily dissolved by condensed water, resulting in problems such as the sustainability of hydrophilicity on the fin surface and the effect on corrosion resistance. Yes, and the cost is high. Furthermore, in the method (3) above,
There is a problem in that the resin neutralizing agent formed on the fin is washed out by water over time, and the hydrophilicity of the film gradually decreases, resulting in poor hydrophilic sustainability.

[0005] In addition, air conditioners have become smaller and lighter in recent years, and heat exchangers are also compactly designed, so the fin spacing has become smaller, and higher hydrophilicity is required, with a contact angle of 30° with water.
The following has become essential.

Furthermore, as the aim is to provide a comfortable living space, the generation of odor has recently become a problem. The use of coating agents mixed with antibacterial agents and preservatives has also been proposed as a countermeasure against initial paint film odors and unpleasant odors (at the start of operation) caused by microorganisms generated in air conditioners (JP-A-Sho 58-10
051, JP-A-61-168675, etc.) are still insufficient.

As described above, the hydrophilic treatment agents currently in practical use in the above-mentioned (1) fin aftercoat method do not fully meet many of these demands, and are not particularly suitable for this method. There is also a desire to develop a hydrophilic treatment composition that has better hydrophilicity and is also advantageous in terms of odor.

[0008] The latter (2) also has problems such as deterioration of corrosion resistance due to destruction of the hydrophilic coating during fin molding.

[0009]

[Means for Solving the Problem] As a result of intensive research to solve the above problems, the present inventors have found that the polyhydric alcohol component has two hydroxyl groups in one molecule and three hydroxyl groups in one molecule. Using a mono- or polyether polyol mixture having each of the above hydroxyl groups, C1 to 7 as the acid component
The present inventors have discovered that all of the above-mentioned drawbacks can be solved by using a composition in which a curing agent is blended with a hydroxyl group-containing polyester resin using an aliphatic dibasic acid, and the present invention has been completed.

That is, the present invention uses a mono- or polyether polyol mixture having two hydroxyl groups in one molecule and three or more hydroxyl groups in one molecule as the polyhydric alcohol component, and uses a mono- or polyether polyol mixture as the polybasic acid component. C1-7 A hydrophilic treatment composition characterized by containing a hydroxyl group-containing polyester resin using an aliphatic dibasic acid and a curing agent as a curable resin composition, preferably further containing an antibacterial agent. The present invention also relates to a hydrophilic treatment method characterized by applying the composition to aluminum heat exchanger fins.

First, the hydrophilic treatment composition of the present invention will be described. The composition of the present invention is a liquid composition containing a hydroxyl group-containing polyester resin and a curing agent as a curable resin composition.

The hydroxyl group-containing polyester resin includes a mono- or polyether polyol (hereinafter abbreviated as "polyether diol") having two hydroxyl groups in one molecule as a polyhydric alcohol component and three hydroxyl groups in one molecule as a polyhydric alcohol component. Mono- or polyether polyol having 1 or more hydroxyl groups (hereinafter abbreviated as "polyether polyol")
This is a hydroxyl group-containing polyester resin using C1-7 aliphatic dibasic acid as the polybasic acid component.

Polyether diol has one or more ether bonds in its molecule, preferably 1 to 200, more preferably 1 to 100, and has primary and/or secondary ether bonds at both ends of its molecular main chain. It is a chain compound with hydroxyl groups.

The above polyether diol preferably has the following general formula (I):

Polyethylene glycol represented by [Chemical formula 1], general formula (II)
:

Polypropylene glycol represented by [Chemical 2], as a structural unit formula,

[Chemical 3]

n in the above general formulas (I) and (II) and the total number of unit formulas (III) and (IV)
is an integer from 2 to 200, preferably from 2 to 100. If the number n is less than 2, a coating film with excellent hydrophilicity cannot be formed, while if it exceeds 200, water resistance, corrosion resistance, etc. will deteriorate, which is not preferred.

Regarding the type of hydroxyl group possessed by the polyether diol, primary hydroxyl groups are preferred from the viewpoint of ease of synthesis of the hydroxyl group-containing polyester resin.

The polyether polyol has one or more ether bonds in one molecule, preferably about 1 to 600, more preferably about 3 to 300, and contains three or more hydroxyl groups in one molecule. It is a branched chain compound. If the number of ether bonds is less than one, a coating with excellent hydrophilicity cannot be formed. Moreover, if the number exceeds 600, water resistance, corrosion resistance, etc. will deteriorate, so it is preferable to keep the number within this range.

[0018] As the polyether polyol, for example, one obtained by addition polymerizing a cyclic ether using a trihydric or higher hydric alcohol as a raw material can be used.

Polyhydric alcohols having a valence of 3 or more are those having 3 or more hydroxyl groups in the molecule that can be polymerized with a cyclic ether, and specifically include glycerin, trimethylolpropane, trimethylolethane, diglycerin, and triglycerin. , 1,2,6-hexanetriol, pentaerythritol, dipentaerythritol, sorbitol, and the like. Among the above, preferred are trimethylolpropane, trimethylolethane, glycerin, pentaerythritol, and the like. In addition, the above polyhydric alcohol is 1
It can be used as a species or in combination of two or more species.

[0020] Cyclic ether is a compound having one ether bond in its cyclic structure, and specific examples thereof include ethylene oxide, propylene oxide, and butylene oxide. These materials can be used alone or in combination of two or more. Among these, ethylene oxide and propylene oxide are preferred.

Specific examples of polyether polyols include general formula (V):

Ethylene oxide or propylene oxide addition polymer of trimethylolethane represented by formula (VI)
:

An ethylene oxide or propylene oxide addition polymer of trimethylolpropane represented by the general formula (VII
):

Ethylene oxide or propylene oxide addition polymer of glycerin represented by formula (VIII):

[C7
] Preferred examples include ethylene oxide or propylene oxide addition polymers of pentaerythritol.

Further, in the general formulas (VI) to (VIII), the number of m is such that the total coefficient of m1, m2, m3 and m4 is 1 or more, preferably the number of each of m1 to m4 is 1 to 200, and further, Preferably it is an integer from 1 to 100. Further, the numbers m1 to m4 may be the same or different.

The polybasic acid component has two carboxyl groups in one molecule and one anhydride carboxyl group in one molecule, and the residue bonded to the carboxyl group or the anhydride carboxyl group is C1-72. saturated or unsaturated aliphatic hydrocarbon groups. The aliphatic hydrocarbon group may be either linear or branched.

[0024] As the polybasic acid component, in particular, the following general formula (IX): HOOC Ct H2tC00H
(IX) (t is an integer from 1 to 7), such as saturated aliphatic dibasic acids such as malonic acid, succinic acid, glutaric acid, adipic acid, and superric acid, and their anhydrides (such as anhydrous succinic acid, etc.), the following general formula (X): HOOC Cp H2p-2COOH
(X) (p represents an integer of 1 to 7), such as unsaturated aliphatic dibasic acids such as fumaric acid and itaconic acid, and their anhydrides (such as maleic anhydride) and tetrahydrophthal acid, hexahydrophthalic acid, 3-methylhexahydrophthalic acid,
Included are aliphatic dibasic acids such as 3-methyltetrahydrophthalic acid and their anhydrides.

The aliphatic carbon number of the polybasic acid is an integer of 1 to 7, preferably 1 to 4. If the number of carbon atoms exceeds 7, a coating with excellent hydrophilicity cannot be formed.

The hydroxyl group-containing polyester resin used in the present invention contains the above polyhydric alcohol component and C1-7 aliphatic 2
It can be produced by carrying out an esterification reaction with a basic acid.

[0027] When the polyhydric alcohol component and the dibasic acid component are subjected to an esterification reaction, the blending ratio of both components is approximately 15 to 8 in the total amount of both components.
5% by weight, preferably about 20-75% by weight, dibasic acid component about 15-85% by weight, preferably about 25-80% by weight
range is suitable. The proportion of the polyhydric alcohol component is greater than about 85% by weight, and the proportion of the dibasic acid component is about 1% by weight.
If it is less than 5% by weight, water resistance, corrosion resistance, etc. will decrease, and on the other hand, if the proportion of polyhydric alcohol component is less than about 15% by weight,
If the proportion of the dibasic acid component exceeds about 85% by weight, hydrophilicity etc. will decrease, which is not preferable. Further, the blending ratio of polyether diol and polyether polyol in the polyhydric alcohol component is about 30 to 95% by weight, preferably about 40 to 95% by weight of polyether diol in the total amount of both components.
0% by weight, about 5-70% by weight of polyether polyol,
Preferably a range of about 10 to 60% by weight is suitable. If the proportion of polyether diol is less than about 30% by weight and the proportion of polyether polyol exceeds about 70% by weight, the production stability of polyester etc. will decrease;
the proportion of polyether diol is greater than about 95% by weight;
If the proportion of polyether polyol is less than about 5% by weight, hydrophilicity etc. will decrease, which is not preferable.

[0028] In the hydroxyl group-containing polyester resin used in the composition of the present invention, other polyhydric alcohols other than the above polyether diol and polyether polyol can be blended as the polyhydric alcohol component, if necessary. Examples of the other polyhydric alcohol components include ethylene glycol, propylene glycol, butanediol, neopentyl glycol, butylene glycol, pentanediol, dimethylpropanediol, hexanediol, hydrogenated bisphenol A, cyclohexanedimethanol, and trimethylene glycol. , tetramethylene glycol, hexamethylene glycol, trimethylolethane, trimethylolpropane, glycerin, diglycerin, dipentaerythritol, sorbitol, diethanolamine, triethanolamine, diisopropanolamine, triisopropanolamine, cyclohexyldiisopropanolamine, methyldiethanolamine, Includes methyldiisopropanolamine and the like.

When the other polyhydric alcohol component is used, the total proportion of the polyhydric alcohol component and the aliphatic dibasic acid is about 80% by weight or less, preferably about 70% by weight or less. . If the blending ratio exceeds about 80% by weight, the hydrophilicity of the coating will decrease, which is not preferable.

In addition, in the hydroxyl group-containing polyester resin used in the composition of the present invention, the above-mentioned C
1 to 7 Polybasic acids other than aliphatic dibasic acids can be blended as necessary. Examples of the other polybasic acid components include aliphatic saturated dibasic acids such as azelaic acid, sebacic acid, dodecynylsuccinic acid and anhydrides thereof, phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, pyromellitic acid and Included are aromatic polybasic acids such as these anhydrides, methylcyclohexenetricarboxylic acid, het acid, tetrachlorophthalic acid, hexahydrotrimellitic acid, and alicyclic polybasic acids such as these anhydrides.

[0031] When the other polybasic acid component is used, the total proportion of the polyhydric alcohol component and the aliphatic dibasic acid is about 80% by weight or less, preferably about 70% by weight or less. . If the blending ratio exceeds about 80% by weight, the hydrophilicity of the coating will decrease, which is not preferable.

[0032] In the hydroxyl group-containing polyester resin used in the composition of the present invention, aromatic acids such as fatty oils and monobasic acids other than fatty acids, such as benzoic acid and P-tert-benzoic acid, may be added depending on molecular weight adjustment and required coating performance. Group 1 basic acids can be blended. The aromatic monobasic acid is usually blended in a total amount of about 40% by weight or less of the polyhydric alcohol component and the aliphatic dibasic acid. Furthermore, it is not preferable to use higher fatty oils or fatty acids of C8 or higher as the monobasic acid because the hydrophilicity of the coating decreases.

The hydroxyl group-containing polyester resin is treated under the same conditions as ordinary polyester resins, for example, 150 to 250°C.
It can be produced by reacting for 1 to 15 hours.

The hydroxyl group-containing polyester resin used in the composition of the present invention has a hydroxyl value of about 30 to 250, preferably about 3.
A range of 0-200 is suitable. When the hydroxyl value is less than about 30, the crosslinking density of the coating decreases, making it difficult to obtain a hydrophilic coating with excellent durability.On the other hand, when the hydroxyl value is greater than about 250, water resistance etc. decrease, which is undesirable.

In addition, the hydroxyl group-containing polyester resin has a molecular weight of about 500 to 20,000 from the viewpoint of coating durability and hydrophilicity.
, preferably in the range of about 1,000 to 15,000. Furthermore, the polyester resin can also contain carboxyl groups as necessary,
The content is preferably in the range of, for example, an acid value of about 300 or less.

The curing agent used in the composition of the present invention is for crosslinking and curing the above-mentioned hydroxyl group-containing polyester resin by heating, and is a functional group that crosslinks with the hydroxyl group in the polyester resin (for example, hydroxyl group, alkyl ether). group, blocked isocyanate group, etc.). Specifically, there are methylolated or alkyl etherified melamine resins modified with one or more selected from monohydric alcohols (having 1 to 5 carbon atoms), urea resins, and benzoguanamine resins. The compound having a blocked isocyanate group is obtained by blocking the isocyanate group of an isocyanate compound with a blocking agent. Isocyanate compounds include tolylene diisocyanate, an adduct of tolylene diisocyanate and trimethylolpropane, diphenylmethane diisocyanate, methylene diisocyanate, hexamethylene diisocyanate, an adduct of hexamethylene diisocyanate and trimethylolpropane, xylylene diisocyanate, and lysine diisocyanate. Examples of blocking agents include phenol, thiourea, methanol, propanol, n-butanol, t-butanol, ethyl acetoacetate, dimethyl malonate, and ε-caprolactam.

The composition of the present invention has the above-mentioned hydroxyl group-containing polyester resin and curing agent as main components, and the composition ratio of these two components is based on the total amount of the two components. 60% by weight, especially 95-70% by weight, curing agent 3-40% by weight, especially 5-30% by weight are preferred.

The composition of the present invention is a liquid composition using an organic solvent and/or water as a solvent or dispersion medium. Further, the hydroxyl group-containing polyester resin used in the composition of the present invention has excellent solubility in water, and therefore can be used as an aqueous composition using water as the main solvent. Furthermore, the resin can be easily dissolved or dispersed in water even if it does not contain a carboxyl group.

In the composition of the present invention, it is preferable to use an aqueous composition in which a hydroxyl group-containing polyester resin and a curing agent dissolved in an organic solvent are dispersed in water, particularly from the viewpoint of production, environmental protection, and safety.

The organic solvent may be one that dissolves the hydroxyl group-containing polyester resin and the curing agent and is substantially inert to these components, such as hydrocarbons such as toluene, xylene, naphtha, mineral spirit, octane, and cyclohexane. Alcohols such as methanol, ethanol, butanol, cyclohexanol, and heptanol, dioxane, methyl cellosolp, butyl cellosolp, methyl carbitol, and the like can be used.

The composition of the present invention may contain an antibacterial agent if necessary, and the antibacterial agent must satisfy the following conditions. (1) Low toxicity and high safety; (2) Heat, light, acid,
It must be stable against alkalis, etc., poorly soluble in water, and have excellent persistence; (3) It must have bactericidal properties at low concentrations or the ability to inhibit the growth of bacteria. , (4) The efficacy does not decrease even when incorporated into the composition, and the safety of the composition is not impaired; (5)
The new water resistance of the coating formed on the fin surface and the corrosion resistance of the fin are not affected.

Antibacterial agents that meet these conditions are known aliphatic and aromatic organic compounds and inorganic compounds. For example, 2-(4-thiazolyl)-benzimidazole, n-(fluorodichloromethylthio)phthalimide, N-dimethyl-N'-phenol-N'-(fluorodichloromethylthio)-sulfamide, o-phenylphenol, 10,10' -oxybisphenoxyarsine, zinc pyrithione, 2,3,5,6-tetrachloro-4-(methylsulfonyl)pyridine, 2,4,5
, 6-tetrachloroisophthalonitrile, diiodomethyl-p-tolylsulfone, 2-benzimidazole methyl carbamate, bis(dimethylthiocarbamoyl)
Disulfide, N-(trichloromethylthio)4-cyclohexene 1,2-dicarboximide and barium metaborate, copper borate, zinc borate, zinc-copper-silver-
A typical example is zeolite. These antibacterial agents can be used alone or in combination.

The blending ratio of the above-mentioned antibacterial agent is 1 to 3 in terms of solid content weight relative to the total amount of the above-mentioned hydroxyl group-containing polyester resin.
It is preferably in the range of 0% by weight, and more preferably 5 to 20% by weight. When the blending amount exceeds 30% by weight, the safety and film-forming properties of the composition tend to be impaired, and the hydrophilicity of the resulting film and the corrosion resistance of the material tend to be impaired.

The composition of the present invention may further contain known surfactants, antifoaming agents, etc., if necessary.

In the hydrophilic treatment method of the present invention, the composition thus obtained is used as a hydrophilic treatment agent for aluminum fins, the concentration of which is adjusted appropriately, and the composition is applied using conventionally known methods such as dip coating, shower coating, spray coating, and roll coating. This is done by applying paint or the like to the fins or molded heat exchanger fins and letting it dry.

In the method of the present invention, a practical hydrophilic film can be formed even if the composition of the present invention is applied to untreated fin materials that have only been degreased and washed; From the viewpoint of corrosion resistance, etc., it is preferable to apply the composition of the present invention to the fin after subjecting the fin to a conventionally known surface treatment for aluminum, such as phosphoric acid chromate treatment or chromate chromate treatment, to form a hydrophilic coating. .

The thickness of the hydrophilic film obtained by the method of the present invention is preferably in the range of 0.2 to 5 μm, more preferably 0.5 to 3 μm. If the film thickness is less than 0.2 μm, the sustainability of hydrophilicity may not be sufficient, and if it exceeds 5 μm, the heat dissipation efficiency of the fins may decrease.

The composition of the present invention is particularly suitable for dip coating, and in the case of such dip coating, a bath in which the solid concentration of the processing agent is usually adjusted to a range of 2 to 10% by weight, and this bath is Then dip-paint the fins. Dip-coated fins are typically preformed and assembled heat exchanger aluminum fins that are dipped into a bath, pulled out, and then painted.
Appropriate baking conditions, such as 120-200℃ and 10-30℃
A hydrophilic coating having the above-mentioned coating thickness can be obtained by baking for a minute.

The composition of the present invention can also be used as a coating agent for preventing dew condensation and snow and ice build-up on molded plastic film products, ceramic molded products, and other molded buildings and vessels.

[0050]

[Operation and effects of the invention] The hydroxyl group-containing polyester resin used in the present invention contains a polyether diol component and an aliphatic diol component.
The basic acid component forms a linear structure with ether bonds, so the coating has excellent hydrophilicity, and the polyether polyol component and the aliphatic dibasic acid component form a branched structure with ether bonds, ensuring the coating remains hydrophilic. I think my sexuality has improved. Further, the ether bonds contained in the resin impart hydrophilicity and are chemically stable and are not hydrolyzed at all, so that the hydrophilicity of the coating can be maintained for a long period of time. Furthermore, the dibasic acid component used in combination with the polyether diol and polyether polyol is an aliphatic dibasic acid with a relatively short carbon number, which itself has relatively high hydrophilicity, so it is good for making the coating hydrophilic. influence

The aluminum fin material formed by the treatment method using the composition of the present invention has improved hydrophilicity (full surface water wettability and contact angle with water of 30° or less), which had been a problem in the past.
, excellent continuous molding processability (mold wear resistance). Furthermore, by incorporating an antibacterial agent, it is possible to improve antibacterial properties and suppress odor generation while maintaining the above performance.

[0052]

[Examples] The present invention will be specifically explained below with reference to production examples, working examples, and comparative examples.

Production Example 1 Polyethylene glycol 200 (weight average molecular weight 200
) 28.8 parts by weight, glycerin ethylene oxide 10
In the present invention, a mixture consisting of 51.1 parts by weight of molar adduct, 20.1 parts by weight of maleic anhydride and 3 parts by weight of xylene was reacted at 160 to 230°C with stirring in a nitrogen gas atmosphere for about 8 hours. A polyester resin to be used was obtained. Regarding the resin, the hydroxyl value was 128, the acid value was 30, and the polybasic acid/polyhydric alcohol (molar ratio) was 0.85.

Production Example 2 Polyethylene glycol 400 (weight average molecular weight 400
), 29.5 parts by weight of a 20 mol adduct of pentaerythritol with propylene oxide, 18.8 parts by weight of adipic acid, and 3 parts by weight of xylene were reacted in the same manner as in Production Example 1 above to obtain the present invention. A polyester resin used in the invention was prepared. Regarding the resin, the hydroxyl value was 74, the acid value was 20, and the polybasic acid component/polyhydric alcohol component (molar ratio) was 0.85.

Production Example 3 Polypropylene glycol 200 (weight average molecular weight 20
0) A mixture consisting of 27.4 parts by weight, 45.8 parts by weight of a 15 mole adduct of trimethylolethane with ethylene oxide, 268 parts by weight of tetrahydrophthalic anhydride, and 3 parts by weight of xylene was reacted in the same manner as in Production Example 1 above. A polyester resin used in the present invention was prepared. Regarding the resin, the hydroxyl value is 117, the acid value is 60, and the polybasic acid component/
The polyhydric alcohol component (molar ratio) was 0.9.

A mixture consisting of 70.2 parts by weight of polyethylene glycol 400 (weight average molecular weight 400), 4.2 parts by weight of pentaerythritol, 25.6 parts by weight of adipic acid and 3 parts by weight of xylene was reacted in the same manner as in Production Example 1. Thus, a polyester resin for comparative example was prepared.

Production Example 5 A comparative example was prepared by reacting a mixture consisting of 26.7 parts by weight of ethylene glycol, 10.4 parts by weight of pentaerythritol, 62.9 parts by weight of adipic acid and 3 parts by weight of xylene under the same conditions as in Production Example 1. A polyester resin was created for the purpose.

Example 1 70 parts by weight (solid content) of the polyester resin obtained in Production Example 1
A mixture of 30 parts by weight (solid content) of "Beccamin N" (manufactured by Dainippon Ink & Chemicals, Ltd., water-soluble urea resin liquid) was diluted with water to obtain a hydrophilic treatment composition with a solid content of 7%.

Next, the aluminum plate (A1050, plate thickness 0.1 mm) was degreased with an alkaline degreaser (manufactured by Japan CP Chemical Co., Ltd., trade name "Chem Cleaner 561B"), and then a chromate treatment agent (made by Nippon Barcalizing Co., Ltd.) was degreased.
Co., Ltd., trade name "Alchrom 713") was used for chromate treatment (chromium equivalent coating amount: 50 mg/m2), and using this as the object to be coated, the above-mentioned hydrophilic treatment composition was applied to a dry film of 1 μm. Then, it was baked at 160° C. for 30 minutes to form a hydrophilic treated film.

The resulting hydrophilized plate was tested for hydrophilicity, corrosion resistance, antibacterial properties, etc. The test results are shown in Table-2.

Examples 2 to 4 and Comparative Examples 1 to 2 A hydrophilic treatment composition with a solid content of 7% was obtained in the same manner as in Example 1, except that the formulations shown in Table 1 were used. A hydrophilic treatment film was formed in the same manner. In addition, the compounding amounts in Table 1 are as follows:
It is a solid content display.

The obtained hydrophilic treated plate was subjected to the same test as in Example 1, and the test results are shown in Table 2.

[0063]

[Table 1]

[0064]

[Table 2] The test method in Table 2 was carried out using the following method. (*1) Water wettability: After applying press oil to the coated plate, the coated plate was degreased for 5 minutes with the steam of Torichlene (manufactured by Toagosei Kagaku Co., Ltd., trade name: “Toriclean-S”). 5 in running water (water flow rate 15 kg/hour per square meter of coated plate)
After being immersed for 00 hours, the wet state of the water on the surface of the coated plate when pulled up was visually determined. A condition in which the entire surface was wet with water was evaluated as good (〇). The water-repellent condition was rated as poor (x). (*2) Contact angle: The contact angle between the coated plate and water is measured using a contact angle meter DCAA model manufactured by Kyowa Kagaku Co., Ltd. after drying the treated plate at 80° C. for 5 minutes. (*3) Corrosion resistance: Based on JIS-Z-2371 salt spray test method. The test time was 500 hours. A case where there was no white rust or blistering was rated as good (〇). (*4) Antibacterial property: According to JIS-Z-2911. A mixed spore suspension of the following test bacteria is sprayed onto each treated plate, and the plate is allowed to stand at a temperature of 27°C for 28 days, after which the degree of proliferation of bacteria (mold) on the treated plate surface is visually observed. A film in which there was no growth or adhesion of bacteria on the surface of the film was rated as good (〇). Items with mold growth or adhesion on the coating surface are considered defective (x).
And so.

Claims (3)

[Claims] Claim 1: A mono- or polyether polyol mixture having two hydroxyl groups in one molecule and three or more hydroxyl groups in one molecule is used as the polyhydric alcohol component, and a C1-7 fatty acid is used as the polybasic acid component. 1. A hydrophilic treatment composition comprising, as a curable resin composition, a hydroxyl group-containing polyester resin using a group dibasic acid and a curing agent. 2. A hydrophilic treatment composition, characterized in that the composition according to claim 1 is blended with an antibacterial agent. 3. A hydrophilic treatment method comprising applying the composition according to claim 1 or 2 to aluminum heat exchanger fins.