HK1165456B - Cleaner for car air-conditioner - Google Patents

Description

Detergent for automobile air conditioner

Technical Field

The present invention relates to a detergent which can be efficiently adsorbed on a base material of an automobile air conditioner, such as a metal material such as aluminum, an aluminum alloy, a magnesium alloy, or an iron alloy, and a resin material such as a hydrophilic resin such as acrylamide coated thereon, and has a long-term antibacterial effect, and exhibits an excellent deodorizing effect and a good rust-proof effect.

Background

A detergent for an automobile air conditioner is used to deodorize offensive odors such as cigarette odor by eliminating microorganisms such as bacteria and mold generated in a line of the automobile air conditioner.

As the detergent for an air conditioner of an automobile, a spray gun type and a mousse type are known, and can be appropriately selected and used according to the place and purpose of use.

For example, in the case of a spray gun type detergent for an automobile air conditioner, a spray gun is inserted into the automobile air conditioner to spray the detergent, and the detergent is used to perform washing, antibacterial treatment, and deodorization treatment of the inside of the air conditioner, particularly an evaporator (see patent document 1).

On the other hand, the mousse-like detergent for an air conditioner of an automobile has the following advantages when treated therewith: the chemical is foamed and spread directly in the air conditioner circuit of the car, not only can wash the evaporator, but also can wash its peripheral apparatus with high efficiency, nevertheless, because the bubble invades the driving part of the blower unit, such as the engine, there is the disadvantage that the electric system trouble such as causing short circuit stops the washing processing operation, makes the engine rusty and deteriorates.

In addition, the following methods are also disclosed: a method of dispersing an antibacterial/antifungal agent in a solvent mainly composed of water using an alkali metal salt of a fatty acid having a tertiary carboxyl group and having 8 or more carbon atoms as a dispersant to obtain a stock solution, and spraying the stock solution onto an air-conditioning line to adhere the same (see patent document 2); a method of deodorizing by mixing 5 to 20 wt% of an organic nitrogen-sulfur antibacterial/antifungal agent, 0.1 to 7 wt% of a rust preventive agent, 1 to 10 wt% of a surfactant, and 5 to 20 wt% of a solvent with respect to an aqueous deodorant stock solution to prepare an air conditioning deodorant stock solution, diluting the air conditioning deodorant stock solution with water, spraying the diluted stock solution into an air line of an air conditioner in a vehicle interior, and suppressing bacteria and molds adhering to an evaporator part (see patent document 1); and an automobile air conditioner detergent (patent document 3 reference) composed of 90 to 70 mass% of a stock solution containing 0.01 to 5 mass% of an organic antimicrobial and antifungal agent, 0.01 to 5 mass% of a deodorant composed of a mixture of an organic carboxylic acid or a salt thereof and a natural extract, 0.01 to 5 mass% of a rust preventive, and 0.1 to 10 mass% of a surfactant, and 10 to 30 mass% of dimethyl ether as a propellant.

However, the above-mentioned detergent for an air conditioner for an automobile or antibacterial/deodorant agent cannot be said to be a satisfactory detergent for an air conditioner for an automobile because the antirust effect is reduced when the detergent or antibacterial/deodorant agent is formulated so as to place importance on the detergent effect and the antibacterial/antifungal effect, and the detergent effect and the antibacterial/antifungal effect are reduced when the detergent or antibacterial/deodorant agent is formulated so as to place importance on the antirust effect.

Documents of the prior art

Patent document

Patent document 1: JP9-108311A (patent claims and other parts)

Patent document 2: JP3-146063A (patent claims and other parts)

Patent document 3: JP2003-261900A (patent claims and other parts)

Disclosure of Invention

Problems to be solved by the invention

The present invention provides a detergent for an automobile air conditioner, which overcomes the above disadvantages of conventional detergents for an automobile air conditioner, has excellent antibacterial and antifungal properties and deodorizing properties as well as detergency, and exhibits excellent rust-proofing properties, and can provide an effect of being stable for a long period of time without impairing the functions of driving parts such as an engine of an evaporator and a blower unit.

Means for solving the problems

The present inventors have made various studies on a detergent for an air conditioner of an automobile, and as a result, have found that: it is known that halogen is a cause of rust generation, and the present invention has been completed based on the findings that a detergent for an automobile air conditioner having good detergency, antibacterial antifungal properties, deodorant properties, and excellent rust-proofing properties over a long period of time can be obtained by selecting a halogen-free component as each component, that is, a mixture containing a di-long-chain alkyl di-short-chain alkyl ammonium salt of carboxylic acid as an antibacterial and antifungal agent, a plant extract as a deodorant, a halogen-free organic rust-proofing agent as a rust-proofing agent, and a halogen-free nonionic surfactant as a detergent component (further preferably, a halogen-free hydrophilic film-forming agent is added) dissolved in an alcoholic organic solvent to prepare a liquid composition, and then, injecting nitrogen gas as a propellant thereinto.

That is, the present invention provides a detergent for an air conditioner of an automobile, wherein a nitrogen gas as a propellant is introduced into a liquid composition and the injection pressure is adjusted to 0.6 to 0.9MPa, the liquid composition comprising, based on the total amount of the liquid composition: (A) 0.1 to 5 mass% of a di-long-chain alkyl di-short-chain alkyl ammonium carboxylate, (B) 0.5 to 5.0 mass% of a plant extract, (C) 0.1 to 5.0 mass% of an organic rust inhibitor containing no halogen atom, (D) 1.0 to 10.0 mass% of a nonionic surfactant containing no halogen atom, and the balance being an alcoholic organic solvent.

ADVANTAGEOUS EFFECTS OF INVENTION

The invention provides a good detergent for an automobile air conditioner, which not only can effectively wash the pollution of the automobile air conditioner, but also can endow the places where condensation occurs in the automobile air conditioner with antibacterial and anti-mildew properties, and can inhibit the generation of odor caused by the propagation of microorganisms for a long time.

Detailed Description

The detergent of the present invention is required to use a dicarboxylic acid di-long-chain alkyl di-short-chain alkyl ammonium salt containing no halogen atom as a counter ion, in consideration of low corrosion resistance to metal members in air-conditioning lines and metal members of aerosol containers, and adsorption to base materials such as metal materials and surface-coated resin materials constituting air-conditioners, as an antibacterial and antifungal agent used as component (a).

The long-chain alkyl group is preferably an alkyl group having 8 to 12 carbon atoms, and the short-chain alkyl group is preferably an alkyl group having 1 to 3 carbon atoms.

The carboxylic acid forming the counter ion is preferably a mono-or dicarboxylic acid having 2 to 8 carbon atoms.

As component (A), didecyldimethylammonium adipate (salt of acid ジデシルジメチルアンモニウムアジピン) is particularly preferred. In order to enhance the antibacterial effect when using a detergent, an isothiazoline-based compound (e.g., 2-methyl-4-isothiazolin-3-one, 1, 2-benzisothiazolin-3-one, N-butyl-1, 2-benzisothiazolin-3-one, etc.), an amino acid having an amino group or a carboxyl group in the molecule (e.g., sodium alkylbis (aminoethyl) glycinate, sodium dodecylaminopropionate, etc.) may be used in combination.

In the detergent of the present invention, a deodorant containing a plant extract may be used as the component (B) in order to quickly deodorize the detergent during use or to efficiently suppress odor during microbial growth, cigarette odor, resin odor generated from a member, and other odors. The plant extract is preferably a polyphenol-containing plant extract such as an extract of persimmon or tea. In addition, in order to enhance the deodorizing ability of the component (B), a graft polymer type deodorant obtained by polymerizing a compound having a functional group capable of directly reacting with an odor generation source such as ammonia, acetaldehyde, and various fatty acids, such as a product manufactured by Grafton corporation, trade name "Grafton" may be used in combination.

In addition, although the detergent of the present invention requires the use of an organic rust inhibitor as component (C), benzotriazoles containing no halogen atom, ammonium salts, aliphatic dicarboxylic acid rust inhibitors, p-tert-butylbenzoic acid, and the like can be used so as not to adversely affect air-conditioning members and aerosol metal containers.

Among them, benzotriazole, dicyclohexylammonium nitrite (ジシクロヘキシルアンモニウムニトリト), diisopropylammonium nitrite (ジイソプロピルアンモニウムニトリト), a dibasic fatty acid having 21 carbon atoms, and the like are particularly preferable.

Commercially available products of these rust inhibitors are, for example, available under the trade name "DIACID 1550" (manufactured by Harima corporation) and under the trade name "BT-120" (manufactured by North City chemical industry Co., Ltd.).

These rust inhibitors may be used alone or in combination of 2 or more, and preferably, a mixture of an aliphatic dicarboxylic acid rust inhibitor, or one or both of benzotriazole and diisopropylammonium nitrite with an aliphatic dicarboxylic acid rust inhibitor is used.

The detergent of the present invention is required to use a detergent component as the component (D), and the component (D) is required to be a nonionic surfactant containing no halogen atom so as to be stably dissolved when prepared into a solution, and can be cleaned without damaging the surface to be treated when appropriately used for an evaporator or other solid surface.

Examples of such nonionic surfactants include polyoxyethylene alkyl ethers, alkylamine ethylene oxide (アルキルアミンエチルンオキシド) adducts, alkyldiethanolamides, polyoxyethylene sorbitan fatty acid esters, fatty acid polyoxyethylene methyl ethers, and alkyldimethylamine oxides (アルキルジメチルアミンオキシド). These nonionic surfactants may be used alone or in combination of 2 or more. Among them, alkylamine oxides are particularly preferable from the viewpoint of imparting a sterilizing property when a detergent is used.

In the detergent of the present invention, it is also important to select the mixing ratio of the components (a) to (D) within a specific range.

That is, based on the total amount of the liquid composition, the amount of the component (A) is 0.1 to 5.0% by mass, preferably 0.5 to 3.0% by mass, the amount of the component (B) is 0.5 to 5.0% by mass, preferably 1.0 to 2.0% by mass, the amount of the component (C) is 0.1 to 5.0% by mass, preferably 0.5 to 2% by mass, the amount of the component (D) is 1.0 to 10.0% by mass, preferably 2.0 to 5.0% by mass, and the balance is an alcoholic organic solvent.

If the amount of the component (a) is less than 0.1% by mass, the antibacterial and antifungal effects are insufficient, whereas if it exceeds 5% by mass, the liquid composition itself becomes unstable and a solid component precipitates, and when used as an aerosol, not only does it cause a failure in spraying, but also the amount of liquid adhering after spraying may become excessive and adversely affect the air-conditioning site.

If the amount of the component (B) is less than 0.5% by mass, the deodorizing effect is insufficient, and if it exceeds 5.0% by mass, the stability of the liquid composition itself is insufficient, and aerosol spray is hindered by precipitation of solid components.

If the amount of the component (C) is less than 0.1% by mass, the rust-preventive effect is insufficient, and the air-conditioning base material cannot be sufficiently protected, whereas if the amount is 5.0% by mass or more, the stability of the liquid composition itself cannot be ensured, and further, ejection failure due to precipitation of solid components may occur.

If the amount of the nonionic surfactant as the component (D) is less than 1.0 mass%, the stability of the liquid composition is impaired and separation is likely to occur, resulting in a decrease in detergency, and if it exceeds 10.0 mass%, it may adversely affect the air-conditioning base material.

Therefore, in order to maintain sufficient detergency and to exhibit excellent antibacterial and antifungal effects and deodorizing effects and to maintain excellent rust-proofing properties for a long period of time, it is necessary to select the following range: 0.1 to 5.0 mass% of the component (A), 0.5 to 5.0 mass% of the component (B), 0.1 to 5.0 mass% of the component (C), and 1.0 to 10.0 mass% of the component (D) based on the total amount of the liquid composition.

In addition, since the air conditioner for a vehicle is generally complicated in structure and a filter to be detachably mounted is disposed above the blower, it is necessary to remove fine contamination caused by spores of microorganisms and smoke (ヤニ) of cigarettes while paying attention to the efficient supply of the detergent to the evaporator to be cleaned and without adversely affecting the electronic components mounted in the periphery of the blower, and to efficiently attach the active ingredients in the detergent to the used portion in the air conditioning circuit, and therefore, it is necessary to use a volatile alcohol organic solvent.

As the alcoholic organic solvent, lower alcohols such as methanol, ethanol, n-propanol and isopropanol, ethylene glycol methyl ether and the like can be used, and from the viewpoint of good dispersibility in each component, low toxicity to the human body and easy volatilization, ethanol or an ethanol aqueous solution having an ethanol content of 70 vol% or more is preferable.

The alcoholic organic solvent is used in a proportion of 70 to 99 mass% based on the total amount of the liquid composition. If the amount is less than 70% by mass, the drying property of the detergent is lost, the mist droplets of the aerosol become coarse, and the reaching rate to the evaporator is lowered. When the content is more than 99% by mass, the liquid composition becomes unstable, and the solid component precipitates to prevent the aerosol from being ejected.

The detergent of the present invention may further contain, as component (E), a hydrophilic film-forming agent in addition to the above components (a) to (D), so that the components (a) to (D) for assisting the active ingredients of the detergent are adhered to the treated surface of the air-conditioning base material after drying.

As the hydrophilic film-forming agent, polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylamide, a naphthalenesulfonic acid formaldehyde condensate, a polyether polyol urethane polymer, for example, those available under the trade name "ADEKANOL UH-140S" (manufactured by ADEKA Co., Ltd.) and the like can be used.

These hydrophilic film-forming agents may be used alone, or 2 or more of them may be used in combination.

In the detergent of the present invention, first, the components (a) to (D) and the component (E) to be used are dissolved in an alcoholic organic solvent to prepare a liquid composition having a solid content concentration of 1 to 30 mass%.

The liquid composition thus prepared is filled in an aerosol container by injecting nitrogen gas as a propellant, adjusting the injection pressure to 0.6 to 0.9 MPa. If the ejection pressure is lower than this range, fine mist droplets cannot be formed, and if it is higher than this range, breakage may occur, which is dangerous.

When used as an aerosol, a flexible narrow tube may be provided at the outlet of the aerosol container in order to make the mist finer.

In this case, the diameter of the outlet of the narrow tube is 0.4mm or less, preferably 0.1 to 0.3 mm. Thus, the sprayed mist droplets can reach the evaporator by the air blowing of the air conditioner.

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

The physical properties of examples and comparative examples were evaluated by the following methods.

(1) Stability of

The sample solutions were mixed well, placed in a refrigerator (about 4 ℃ C.), left for 1 week, and then evaluated visually under the following criteria.

O: the liquid was transparent and no floating or precipitation of the precipitate was observed.

X: the liquid appeared white turbid, and floating or precipitation of the precipitate was found.

(2) Antibacterial property

Each sample solution was applied to a standard test plate (10X 25mm) of aluminum and 6-nylon, dried, and then placed in a salt water spray tester (manufactured by Suga tester Co., Ltd.) and allowed to stand. After 14 days, each of the above test plates was taken out, dried, and then placed in the center of a common agar medium (previously coated with Bacillus subtilis) prepared in a 90 mm-diameter petri dish. After 3 days of culture at 25 ℃, evaluation was made according to the size of the diameter of the inhibition loop (block Yen) in accordance with the following criteria.

O: over 20mm

And (delta): 10mm or more and less than 20mm

X: less than 10mm

(3) Mildew resistance

Each sample solution was spread on a paper disk having a diameter of 8mm, and placed in the center of a potato dextrose agar medium (previously coated with Aspergillus niger) prepared in a petri dish having a diameter of 90 mm. After culturing at 25 ℃ for 3 days, evaluation was made according to the size of the inhibition loop diameter according to the following criteria.

O: over 20mm

And (delta): 10mm or more and less than 20mm

X: less than 10mm

(4) Deodorizing property

A malodor source (0.5% ammonia-ethanol solution 0.2cc) was placed in a beaker having a capacity of 5 liters in a desiccator, and after leaving for 30 minutes, the concentration was measured using a gas detection tube manufactured by GASTEC corporation to prepare a control. Subsequently, a lint (ネル cloth) (50X 50mm) impregnated with 0.5cc of each sample liquid was put into a dryer, and the odor concentration was measured in the same manner, and the difference from the control was defined as the deodorization ratio. At this time, the malodor source is not brought into contact with the sample liquid, and the volatile substances are reacted with each other.

O: the deodorization rate is more than 70 percent

And (delta): the deodorization rate is more than 30 percent and less than 70 percent

X: the deodorization rate is lower than 30 percent

(5) Cleaning property

The unused cigarettes were extracted with ethanol, coated on a test piece (25X 50mm) to prepare a contaminated plate, and the color difference was measured in advance with a color difference meter (CR-200, manufactured by Minolta corporation). 100g of the sample solution was placed in a 100ml beaker, and the resulting mixture was stirred at 450rpm for 10 minutes, and then the color difference was measured again to determine the washing rate by the following equation.

Washing rate (%) - (Δ E)₁-ΔE₂)×100/ΔE₁

(ΔE₁: color difference, Δ E, of soiled plates before washing₂: color difference of washed contamination plate)

O: the washing rate is more than 80 percent

And (delta): the washing rate is more than 50 percent and less than 80 percent

X: the washing rate is lower than 50 percent

(6) Rust resistance

The ground iron plate was immersed in each sample solution to immerse the lower half portion of the whole body, and after being left in a thermostatic bath at 50 ℃ for 1 week, the presence or absence of rust was visually observed.

O: no rust generation

And (delta): partial generation of rust

X: rust generation on the entire surface of the plate

(7) Accessibility of liquid

A blower unit of a car air conditioner mounted on a practical vehicle was connected to an evaporator apparatus, the suction surface of the evaporator was covered with B5-size (182 × 257mm) paper, each sample liquid was filled from a gas suction port in the blower unit, an aerosol in which nitrogen gas was injected as an injection agent was injected, the area of the paper to which the sample liquid was attached was measured, and the occupancy ratio was evaluated according to the following criteria.

O: over 80 percent

And (delta): more than 70 percent and less than 80 percent

X: less than 70 percent

Examples 1 to 4 and comparative examples 1 to 4

Liquid compositions having compositions shown in tables 1 and 2 were prepared, and physical properties thereof were evaluated. Next, the liquid composition was filled, an aerosol in which nitrogen gas was injected as a propellant was prepared, and the liquid attainability was evaluated. The results are shown in tables 1 and 2.

[ Table 1]

[ Table 2]

Industrial applicability

Is useful as a detergent for an automobile air conditioner.

Claims (7)

1. A detergent for an air conditioner of an automobile, wherein a liquid composition is prepared by pressing nitrogen gas as a propellant into the liquid composition and adjusting the pressure of the propellant to 0.6 to 0.9MPa, based on the total amount of the liquid composition, and the liquid composition comprises: (A) 0.1 to 5.0 mass% of a carboxylic acid di-long-chain alkyl di-short-chain alkyl ammonium salt having no halogen atom as a counter ion, (B) 0.5 to 5.0 mass% of a polyphenol-containing plant extract, (C) 0.1 to 5.0 mass% of an organic rust inhibitor having no halogen atom, (D) 1.0 to 10.0 mass% of a non-ionic surfactant having no halogen atom, and 70 to 99 mass% of ethanol, the total amount of the above components being 100 mass%,

the long-chain alkyl in the carboxylic acid di-long-chain alkyl di-short-chain alkyl ammonium salt of the component (A) is an alkyl with 8-12 carbon atoms, and the short-chain alkyl is an alkyl with 1-3 carbon atoms.

2. The detergent for an air conditioner in a vehicle according to claim 1, wherein the component (A) is didecyldimethylammonium adipate.

3. The detergent for an automobile air conditioner according to claim 1 or 2, wherein the component (B) is an extract of persimmon or tea.

4. The detergent for an automobile air conditioner according to claim 1, wherein the component (C) is a mixture of an aliphatic dicarboxylic acid type rust inhibitor, or one or both of benzotriazole and diisopropylammonium nitrite salt with an aliphatic dicarboxylic acid type rust inhibitor.

5. The detergent for an air conditioner in an automobile according to claim 1, wherein the component (D) is at least 1 selected from the group consisting of polyoxyethylene alkyl ether, alkyldimethylamine oxide, alkylamine ethylene oxide, alkyldiethanolamide, polyoxyethylene addition fatty acid ester and fatty acid polyoxyethylene alkyl ether.

6. The detergent for an automobile air conditioner according to claim 1, further comprising a hydrophilic coating forming agent as component (E) in addition to components (A) to (D).

7. The detergent for an air conditioner in a vehicle according to claim 6, wherein the component (E) is at least 1 selected from the group consisting of polyvinyl alcohol, polyvinylpyrrolidone, polyacrylamide, a naphthalenesulfonic acid-formaldehyde condensate and a polyether polyol urethane polymer.