KR100556110B1 - Hydrophilic Antibacterial Agent for Evaporator of Air Conditioner - Google Patents

Abstract

The present invention is capable of quickly removing water droplets generated by condensation due to heat exchange in an evaporator, and it is hydrophilic and antibacterial and hydrophilic-antibacterial that can prevent odors and bacterial growth caused by foreign substances such as bacteria, mold and dust. A hydrophilic antimicrobial agent for an evaporator of an air conditioner having improved performance durability (durability of a coating layer) is disclosed.

The constitution of the present invention comprises three-way hybrid block polymers selected from three-way hybrid block polymers of polyoxypropylene-polyoxyethylene-polyoxypropylene and three-way hybrid block polymers of polyoxyethylene-polyoxypropylene-polyoxyethylene. 8 wt%, sodium citrate 2-8 wt%, diethylene glycol 5-15 wt%, polyethylene oxide 0.1-1 wt%, orotan dispersant 0.1-5 wt%, Zinc Pyrithione (C ₁₀ H ₈ N ₂ O ₂ S ₂ Zn: 1-Hydroxy-2 (1H) -pyridinethione), Sodium Pyrithione (C ₅ H ₄ NNaOS) and Dipyrithione (C ₁₀ H ₈ N ₂ O ₂ S ₂ ) 1 to 5% by weight, and the remaining weight% is made of deionized water.

Air Conditioner, Evaporator, Hydrophilic, Antibacterial, Coating, Block Copolymer, Contact Angle, Durable, Titania Phosphate

Description

Hydrophilic Antibacterial Agent for Evaporator of Air Conditioner

The present invention relates to a hydrophilic antimicrobial agent, and more particularly, to a hydrophilic antimicrobial agent for an evaporator of an air conditioner, which is applied to an evaporator of a car or home air conditioner to impart hydrophilicity and antimicrobial properties of the evaporator.

The air conditioner used in automobiles and households is composed of a compressor, a condenser, an evaporator, and the like, and heat exchange is performed by circulating refrigerant in each of these components. That is, the refrigerant compressed at high temperature and high pressure in the compressor is supplied to the condenser and condensed in a high pressure liquid state. The refrigerant condensed in the condenser is sent to the evaporator at low temperature and low pressure to evaporate to cool the surrounding air, and then again in the compressor. The cycle of compression is repeated.

On the other hand, among the above components, in the evaporator, as the low-temperature refrigerant and the air having a higher temperature than the refrigerant perform heat exchange with each other, water droplets due to condensation form on the surface of the evaporator. However, as the air conditioner system becomes smaller and higher in performance, the heat dissipation fins of the evaporator are arranged at tight intervals and high air flow is required, so that the water droplets due to condensation increase ventilation resistance and condensation of water droplets may occur. In order to drain such water droplets quickly, hydrophilic treatment with hydrophilic function is required. In addition, the odor occurs in the air conditioner due to the decay or multiplication of moisture due to condensation in the evaporator and foreign substances such as bacteria, mold, and dust from the outside, and in recent years, such odor problems have emerged as an important issue. Development of hydrophilic antimicrobial agents to solve this problem is in progress.

Representative examples of such hydrophilic antimicrobial agents include hydrophilic antimicrobial coatings composed of inorganic hydrophilic particles such as silicate (SiO ₂ ) and an organic binder. However, as the conventional hydrophilic antimicrobial coating material is aging, odor particles or other contaminants tend to adhere to the inorganic hydrophilic agent, microorganisms tend to multiply, and the organic coating layer cracks due to inorganic particles. Not only does it have a fragile binding structure that falls off, but also has a problem in that the variation in hydrophilicity is severe. Moreover, silica, which is mainly used as a hydrophilic material, has a problem that causes an unpleasant feeling due to its own odor such as cement smell. In addition, since the organic binder reacts with water generated in the evaporator, the hydrophilic functional group and the crosslinking group are differentiated and disappeared, so that the coating layer disappears and the aluminum material, which is the material of the evaporator, is exposed. In other words, the durability of the coating layer will be lost in 1 to 2 years after the operation of the air conditioner. This characterization can be analyzed through the hydrophilic endurance test. The initial hydrophilic contact angle is within 1 to 8 °, but the contact angle after the endurance test is about 40 ° or more, and the antimicrobial properties tend to be weakened as well. Therefore, the odor does not occur at the initial stage of manufacturing in the air conditioner, but after one or two years of operation, problems of odor generation, drainage and deterioration of air conditioner performance are caused.

The present invention has been made to improve the conventional problems as described above, the object is to quickly remove the water droplets caused by condensation due to heat exchange in the evaporator, foreign matters such as bacteria, mold and dust It is to provide a hydrophilic antimicrobial agent for the evaporator of the air conditioner with improved hydrophilicity and antibacterial and hydrophilic-antibacterial performance (durability of the coating layer) that can prevent odor and bacterial growth due to.

Hydrophilic antimicrobial agent for the evaporator of the air conditioner according to the present invention for achieving the above object, the three-way hybrid block polymer of polyoxypropylene-polyoxyethylene-polyoxypropylene and polyoxyethylene-polyoxypropylene-polyoxyethylene 1-8% by weight of the tertiary hybrid block polymer selected from the original hybrid block polymers, 2-8% by weight sodium citrate, 5-15% by weight diethylene glycol, 0.1-1% by weight polyethylene oxide, 0.1-5% by weight urotan dispersant , Zinc Pyrithione (C ₁₀ H ₈ N ₂ O ₂ S ₂ Zn: 1-Hydroxy-2 (1H) -pyridinethione) and Sodium Pyrithione (C ₅ H ₄ NNaOS) and Dipyrithione (C ₁₀ H ₈ N ₂ O ₂ S ₂ The organic antimicrobial agent 1-5 weight% and remaining weight% which mixed any 1 or 2 or more selected from the following) are made into the summary which consists of ion removal water.

Here, the ternary hybrid block polymer selected from the ternary hybrid block polymer of the polyoxypropylene-polyoxyethylene-polyoxypropylene and the ternary hybrid block polymer of polyoxyethylene-polyoxypropylene-polyoxyethylene, sodium citrate and It is preferable that the hydrophilic functional groups of diethylene glycol are dehydrated and condensed with each other to act as a crosslinking group to form a copolymer having a molecular weight in the range of 20,000 to 30,000.

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Further, 0.1 to 5% by weight of a titania phosphate compound composed of titanium dioxide having an anatase type crystal structure and porous calcium phosphate capable of supporting these titanium dioxides may be further added to the above structure. In particular, the titania phosphate compound composed of titanium dioxide having the anatase type crystal structure and porous calcium phosphate capable of supporting these titanium dioxides is preferably micronized into pico particles (10 ^-12 m) and added. Do.

Hereinafter, the configuration of the present invention will be described in detail.

Friend antimicrobial agent of the present invention is composed of a completely organic hydrophilic agent to remove the odor of the hydrophilic antimicrobial itself, the particles are micro-fine to improve the durability of the hydrophilic-antibacterial performance, the water produced by condensation in the evaporator by increasing the number of particles per unit area The hydrophilic-antimicrobial reacted with and degraded the performance loss even after decomposition and vaporization.

That is, the hydrophilic antimicrobial agent of the present invention is a ternary hybrid block selected from ternary hybrid block polymers of polyoxypropylene-polyoxyethylene-polyoxypropylene and ternary hybrid block polymers of polyoxyethylene-polyoxypropylene-polyoxyethylene. 1 to 8% by weight of polymer, 2 to 8% by weight of sodium citrate, 5 to 15% by weight of diethylene glycol, 0.1 to 1% by weight of polyethylene oxide, 0.1 to 5% by weight of orotan dispersant, Zinc Pyrithione (C ₁₀ H ₈ N ₂ O ₂ S ₂ Zn: 1-Hydroxy-2 (1H) -pyridinethione) and Sodium Pyrithione (C ₅ H ₄ NNaOS) and Dipyrithione (C ₁₀ H ₈ N ₂ O ₂ S ₂ ) 1 to 5% by weight of one organic antimicrobial agent and the remaining weight% of deionized water.

Here, the ternary hybrid block polymer is selected from ternary hybrid block polymers of polyoxypropylene-polyoxyethylene-polyoxypropylene and ternary hybrid block polymers of polyoxyethylene-polyoxypropylene-polyoxyethylene as a main hydrophilic agent. Sodium citrate and diethylene glycol act as auxiliary hydrophilic agents. In particular, the hydrophilic functional groups of the ternary interpolymers and sodium citrate and diethylene glycol react with each other by dehydrating to act as a crosslinking group to form a copolymer structure having a molecular weight in the range of 20,000 to 30,000, thereby delaying the decomposition vaporization of the hydrophilic-antibacterial treatment agent. By increasing the durability of the hydrophilic antibacterial performance. Further, the tertiary hybrid block polymer may be selected from the group consisting of ethylene dipropylene-based or propylene diethylene-based polyoxypropylene-polyoxyethylene-polyoxypropylene, or a polyoxyethylene-polyoxypropylene-polyoxyethylene. It is selected and used among ternary hybrid block polymers, and among them, it is more effective to use ternary hybrid block polymers of polyoxypropylene-polyoxyethylene-polyoxypropylene.

In addition, the polyethylene oxide and the orotan dispersant are surfactants that improve uniform coating and smoothness during the coating of hydrophilic antimicrobial agents, and drainage of water generated by condensation on an evaporator, that is, water flowability (droplets dropped on the coating layer flows rapidly. Accuracy: the smaller the contact angle and the more uniform the coating layer, the better the flow).

The hydrophilic antimicrobial agent thus prepared was diluted with deionized water to make a coating agent, and various performance tests were conducted. As a result, the hydrophilic antimicrobial agent improved performance in terms of durability, in particular, hydrophilic-antibacterial performance, compared to the conventional hydrophilic agent. As shown.

On the other hand, in the hydrophilic antimicrobial agent of the present invention having the above configuration, the chemical formula is represented by Ti (OH) X (PO ₄ ) Y, and carries a titanium dioxide having anatase type crystal structure and these titanium dioxide (擔 持) A titania phosphate compound composed of porous calcium phosphate may be further added. Titanium dioxide having anatase type crystal structure expresses the function of a photocatalyst, and the particle size of titanium dioxide may have any size, but is preferably 10 nm or less. The hole size of the porous calcium phosphate and the particle size of the calcium phosphate that can support these titanium dioxide may have any size, but especially in the case of titanium dioxide having a particle diameter of 10 nm or less, the size of 200 nm having a pore of about 30 nm. Calcium phosphate is preferred.
A titania phosphate compound (hereinafter, simply referred to as a `` titania phosphate compound '') composed of titanium dioxide having such an anatase type crystal structure and porous calcium phosphate capable of supporting such titanium dioxide is oxygen in the air ( When contacted with O ₂ ) or water (H ₂ O), a surface reaction occurs to generate divalent active oxygen, which is unstable and causes a reduction reaction to receive electrons, and generates hydrogen peroxide in the reactive oxygen reaction. Hydrogen peroxide becomes a hydroxyl radical (OH-) that undergoes a strong oxidation reaction to decompose organic matter, remove harmful gases, and have super hydrophilicity. When these polar fine titania phosphate compound particles as a pico (10 ^-12 m) is increased, the effect of per unit area durability.

The combination of the titania phosphate compound and the hydrophilic antimicrobial agent described above greatly improves the adhesion of the coating, and when coated on an evaporator, it is possible to significantly reduce the amount of powder generated in the coating layer after the water spray test, thereby improving the hydrophilic antibacterial performance and durability of the coating layer. Can be harvested.

The following is a description of the performance test method and the test results for the hydrophilic antimicrobial agent of the present invention having the configuration as described above.

-Hydrophilic performance test

Hydrophilic performance was determined by testing the initial contact angle characteristics, the durable contact angle characteristics, and the water flowability of the evaporator. The hydrophilic performance was measured using a contact angle meter, and the results are shown in Table 1 below.

<Table 1>

Initial contact angle Endurance contact angle Water flowability Specimen applying hydrophilic antimicrobial agent of the present invention 5.5 ° 18.3 ° 8 sec Specimen Application of Titania Phosphate Addition to the Present Invention 3.7 ° 16.3 ° 9.8 seconds Test Pieces Applying Conventional Hydrophilic-Antibacterial Agents 9.8 ° 28.9 ° 10 sec Untreated Specimen 85.1 ° 46.1 ° Not measurable

Here, the initial contact angle is added dropwise 0.05 cc of water to the site to be measured, measured between 8 to 10 seconds with a contact angle measuring device and the 2θ value is read as the contact angle. At this time, the height of dropping water drops is almost zero.

The endurance contact angle was maintained at a temperature of 40 ° C. and a relative humidity of 90% or more for 6 minutes, and then cooled at a cooling rate of −10 ° C./min, cooled to 0 ° C. or less, and immediately heated at a heating rate of 10 ° C./min. In addition, the contact angle is measured in the same manner as the initial contact angle measurement method after 500 cycles, with one cycle of maintaining the temperature at 40 ° C. and the relative humidity of 90% or more for 6 minutes.

As can be seen in Table 1, the specimens to which the hydrophilic antimicrobial agent of the present invention was applied showed lower initial contact angle and durability contact angle than the specimens to which the conventional hydrophilic antimicrobial agent was applied, and the water flowability was also excellent (the water droplets dropped on the coating layer The faster the flow of water is, the better the contact angle is small and the coating layer is uniform. Moreover, it can be seen that the specimen when the titania phosphate compound of the present invention is added has a more excellent effect.

-Antibacterial test

Antibacterial test was carried out in two ways as follows.

Iii. Bacterial Test (FC-TM-20 Method)

After determining the type of bacteria, the bacteria frozen at -50 ° C are stored in a refrigerator at about 5 ° C 12 hours before the test. In addition, a fertilizer to be cultured with the bacteria to be tested. After mixing the bacteria and the culture medium, in order to determine the culture level that is the standard of the bacteria to be tested, the bacteria were incubated for 24 hours at a humidity of 95% and a temperature of 37 ° C. in a blank state without the material before bacterial culture on the test material ( Determine the number of bacteria at the time of cultivation, the number of bacteria (the measured number of bacteria is the standard for this test). After entering the test, placing the bacteria and the culture medium on the material to be tested (measuring the number of bacteria), incubating for 24 hours at 95% humidity and 37 ° C temperature, and measuring the number of bacteria to compare with the standard test value. Determine the effect of the test material on the bacteria.

Ii. Mold Test (ASTM G21 Method)

Lay the mold to be tested to a certain thickness in a glass bowl, place the specimen to be tested on it, and stand for 3 weeks in a temperature of 25 ° C. within a humidity range of 60 to 100% to observe whether the mold grows on the specimen.

These two tests were carried out in the same manner for the present invention and the conventional hydrophilic antimicrobial applied specimens and untreated specimens, the results are shown in Table 2.

<Table 2>

Bacterial reduction rate Mold rating Specimen applying hydrophilic antimicrobial agent of the present invention 99% Grade 0 Specimen Application of Titania Phosphate Addition to the Present Invention 99% Grade 0 Test Pieces Applying Conventional Hydrophilic-Antibacterial Agents 90% Grade 0 Untreated specimen 25.0% Grade 2

As can be seen from the above test results, the antibacterial properties of the hydrophilic antibacterial agent to which the hydrophilic antimicrobial agent of the present invention was applied were found to be better than the conventional hydrophilic antimicrobial agents.

-Odor test

The odor test was carried out by the following two methods.

Iii. Dry odor evaluation

After the standard test apparatus is prepared at room temperature, the evaporator to be tested is mounted in the apparatus to be tested, and the odor is measured by operating the blower while maintaining the passage wind speed at the smell measuring unit at 1 m / sec.

Ii. Wet odor evaluation

After 72 hours in an ambient temperature of 40 ° C and a relative humidity of 90% or higher, the evaporator to be tested is mounted in a standard test apparatus, and the blower is operated while maintaining the passage wind speed in the odor measuring unit at 1 m / sec. Take it. Just before mounting, apply sufficient water to the entire evaporator.

Iii. Odorability Evaluation Criteria (10 or more Emotional Evaluation Agents)

Smell strength

0 points: odorless

1 point: It seems to have a slight smell

2 points: a slight smell

3 points | pieces: Smells abundantly

4 points: Smells too much

5 points | pieces: Smell is severe enough to sting nose

Odor sign: According to the type of smell, a healthy person evaluates the degree of good or unpleasant taste according to his or her taste by personal sensitivity.

According to the test method described above, the present invention and the conventional hydrophilic-antibacterial applied specimens and untreated specimens were carried out in the same manner, the results shown in Table 3.

<Table 3>

Odor intensity Smell sign deflation Wet deflation Wet Specimen applying hydrophilic antimicrobial agent of the present invention 2.1 2.5 2.3 2.3 Specimen Application of Titania Phosphate Addition to the Present Invention 2.1 2.1 2.1 2.1 Test Pieces Applying Conventional Hydrophilic-Antibacterial Agents 2.5 2.8 2.8 2.8 Untreated specimen 2.6 3.1 2.8 2.5

As can be seen from Table 3, the specimens to which the present invention is applied exhibited superior performance to the specimens to which the conventional hydrophilic antimicrobial agent was applied because of the ability to suppress the occurrence of odor due to the decay of microorganisms, molds, dusts, and the like. .

-Scattering test

In the splash test of the water droplets, the hydrophilic-antibacterial evaporator was mounted on the actual vehicle air conditioner, and then maintained at 4 stages of air conditioner strength for 30 minutes, 20 stages at 1 stage, and then rapidly increased to 4 stages for 5 minutes. Next, the air conditioner was turned off and the amount of scattering of water generated in the evaporator was measured. The test results are shown in Table 4 below.

<Table 4>

Flying weight Specimen applying hydrophilic antimicrobial agent of the present invention 0.4287 g Specimen Application of Titania Phosphate Addition to the Present Invention 0.3512 g Test Pieces Applying Conventional Hydrophilic-antibacterial Agents 0.4957 g

As can be seen in Table 4, the amount of water scattering is reduced when the hydrophilic antimicrobial agent of the present invention is applied as compared with the conventional hydrophilic antimicrobial agent. This can be seen as an effect of the reduction of the contact angle by the block copolymer. In addition, it can be seen that the synergistic effect appears when the titania phosphate compound is added.

-Watering and Percentage Analysis Test

This test is to determine the durability of the coating layer.

The test method, after dropping 2 liters of water per minute to the evaporator unit coated with a hydrophilic antimicrobial agent for 500 hours, completely dried in the shade, and freely falling dried evaporator at a position of 30cm from the ground to finely measure the amount of powder generated Survey with a balance.

The test results are shown in Table 5 below.

<Table 5>

Percent generation amount (grams) Specimen applying hydrophilic antimicrobial agent of the present invention 0.3785 Specimen Application of Titania Phosphate Addition to the Present Invention 0.2643 Test Pieces Applying Conventional Hydrophilic-Antibacterial Agents 0.3791

As shown in Table 5, it can be seen that the application of the hydrophilic antimicrobial agent of the present invention is very good in the amount of generation of powder compared with the case of applying the conventional hydrophilic antimicrobial agent. Moreover, when the diacid titania compound was added, better results were obtained.

Hydrophilic antimicrobial agent for the evaporator of the air conditioner according to the present invention as described above, the water droplets formed by the heat exchange in the evaporator is quickly removed, and the hydrophilicity to prevent odor and bacterial growth caused by foreign substances such as bacteria or mold and dust and Excellent antibacterial effect, not only effective to the health of the air conditioning user, there is an effect that contributes to improving the performance of the air conditioner.

Claims (5)

1 to 8% by weight of ternary hybrid block polymer selected from ternary hybrid block polymer of polyoxypropylene-polyoxyethylene-polyoxypropylene and ternary hybrid block polymer of polyoxyethylene-polyoxypropylene-polyoxyethylene, sodium citrate 2 to 8% by weight, 5 to 15% by weight of diethylene glycol, 0.1 to 1% by weight of polyethylene oxide, 0.1 to 5% by weight of urotan dispersant, Zinc Pyrithione (C ₁₀ H ₈ N ₂ O ₂ S ₂ Zn: 1-Hydroxy 1-5% by weight of an organic antimicrobial agent mixed with any one or two or more selected from -2 (1H) -pyridinethione), Sodium Pyrithione (C ₅ H ₄ NNaOS) and Dipyrithione (C ₁₀ H ₈ N ₂ O ₂ S ₂ ), The remaining weight% is hydrophilic antibacterial agent for evaporator of air conditioner which consists of ion removal water. The method of claim 1, Ternary hybrid block polymers selected from ternary hybrid block polymers of polyoxypropylene-polyoxyethylene-polyoxypropylene and ternary hybrid block polymers of polyoxyethylene-polyoxypropylene-polyoxyethylene, sodium citrate and diethylene glycol A hydrophilic antimicrobial agent for an evaporator of an air conditioner, wherein the hydrophilic functional groups of the hydrophilic functional group are dehydrated and condensed to each other to form a copolymer having a molecular weight in the range of 20,000 to 30,000. delete The method of claim 1, A hydrophilic antimicrobial agent for an evaporator of an air conditioner, further comprising 0.1 to 5% by weight of a titanium dioxide phosphate compound composed of titanium dioxide having an anatase type crystal structure and porous calcium phosphate capable of supporting the titanium dioxide. The method of claim 4, wherein The titania phosphate compound composed of titanium dioxide having the anatase type crystal structure and porous calcium phosphate capable of supporting these titanium dioxides is characterized in that it is added to the micron particles (10 ^-12 m) to be extremely finely added. Hydrophilic antibacterial agent for evaporators of air conditioners.