Preparation process of hydrophilic paint for superthin air conditioner aluminium foil heat exchanger

Abstract

The invention discloses a method for preparing a hydrophilic coating for an ultra-thin air conditioner aluminum foil heat exchanger, which consists of a primer and a top coat, wherein the primer is composed of 15.0-20.0 wt% of hydroxyl emulsion and 1.5-3.0 wt% of amino resin %, cross-linking aid 0.05-0.5wt%, coloring paste 1.5-2.5wt%, and the balance is a mixed solvent; the surface coating is divided into two components, A and B, and the composition of A is: hydrophilic polymerization 25.0~35.0wt% of solids, 5.0~10.0wt% of hydrophilic strengthening agent, 0.5~3.5wt% of surfactant, and the balance is mixed solvent; component B is curing agent 60.0~65.0wt%, deionized water 35.0~40.0 wt%; during construction, use by mixing component A: component B = 9.0 ~ 11.0: 1 weight percentage; the amount of primer of the present invention is 0.8 ~ 1.0g / m2, the amount of topcoat is 0.3 ~ 0.5g / m2, the total film thickness 30-50 nanometers, with excellent adhesion, initial hydrophilicity, continuous hydrophilicity, acid and alkali corrosion resistance, heat resistance, odor resistance, especially good continuous hydrophilicity, contact angle θ≤ 15°, and the aluminum foil for air-conditioning heat exchanger can be pre-coated, which has little wear on the processing mold, and because the coating is ultra-thin, it does not affect the heat exchange performance of the aluminum foil fin itself of the air-conditioning heat exchanger.

Description

Technical field: [0001] The invention relates to a method for preparing a coating, in particular to a method for preparing a hydrophilic coating for an ultra-thin air-conditioning aluminum foil heat exchanger. Background technique: [0002] When the air conditioner is cooling, the water vapor in the air condenses and adheres to the fin surface of the air conditioner's aluminum foil heat exchanger. On the one hand, the attached condensed water tends to form a water bridge between the fins, which increases the ventilation resistance and noise when the air conditioner is running. The efficiency of the heat exchanger is reduced. On the other hand, when condensed water adheres to the fins for a long time, it will absorb dirt in the air and cause corrosion reactions on the surface of the fins, which will also reduce the working efficiency of the heat exchanger. The reaction produces a major component of Al 2 o 3 ·3H 2 O white powder, and blown out with the warm wind, polluting...

AI Technical Summary

Problems solved by technology

[0005] Hydrophilic coating such as CN1405252A disclosed "hydrophilic coating of air-conditioning heat exchange fin", its composition comprises modified epoxy resin, acrylic resin, amino resin, sulfonate surfactant and deionized water, although the hydrophilic Water-based coatings have good long-lasting hydrophilic performance, contact angle θ≤15°, and coating thickness of tens of nanometers, but their acid and alkali corrosion resistance and heat resistance are poor

[0006] Hydrophilic coating such as "hydrophilic coating and preparation method thereof" disclosed in CN1800281A, it consists of water-soluble acrylic resin, containing organosilane, silica sol, methacrylic acid, hydroxyethyl acrylate, N-methylolacrylamide Water-soluble organic-inorganic silicon-acrylic acid composite polymer; although the hydrophilic coating can be coated in a single layer, the durable hydrophilicity is good, and the contact angle θ≤15°, but its acid and alkali corrosion resistance is poor, and the coating is thick , affecting the heat exchange performance of the aluminum foil fin itself

[0007] Hydrophilic coating such as CN1100102C discloses " the film-forming agent of hydrophilic corrosion resistance and excellent film and its pre-coated film aluminum foil and film-forming method ", and its corrosion-resistant primer is composed of water-based epoxy or water-based acrylic acid, melamine resin Or polyisocyanate, its hydrophilic surface is coated with refined water glass or silica sol or fumed silica, cellulose or acrylamide and acetamide or silane and acrylamide or silane and acetamide, although the coating is heat-resistant Performance, acid and alkali resistance and corrosion resistance are good, but the continuous hydrophilic performance is average, the contact angle θ≤25°, and the coating is prone to odor, and the coating is thick, which affects the heat exchange performance of the aluminum foil fin itself

[0008] To sum up, at present, there are some defects in the performance of pre-coated hydrophilic coatings on aluminum foil heat exchangers for air conditioners. It is even more difficult to ensure high performance, light weight and miniaturization of aluminum foil heat exchangers for air conditioners.

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