JP2001158878A - Cooling liquid composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cooling liquid composition which exhibits excellent cooling characteristics and can simultaneously furthermore enhance an anticorrosive effect. SOLUTION: This cooling liquid composition containing a formate and water as main components is characterized by containing 0.01 to 1.0 wt.% of a phosphate and 0.01 to 0.5 wt.% of a triazole compound as anticorrosive additives, and also characterized by containing 0.01 to 5.0 wt.% of at least one compound selected from a 10 to 22C aliphatic dicarboxylic acid, a 7 to 9C aliphatic monocarboxylic acid, its anhydride and its alkali metal salt, and 0.01 to 1.0 wt.% of a triazole compound as anticorrosive additives. Further, the composition preferably contains at least one anticorrosive additive selected from 0.01 to 1.0 wt.% of a thiazole compound, 0.01 to 1.0 wt.% of boric acid compound and 0.01 to 1.0 wt.% of a molybdic acid compound.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling liquid composition used at a low temperature in, for example, refrigerators, ice makers, and other various types of cold storage equipment, and used for cooling a cooling system such as an automobile engine. The present invention relates to a coolant composition to be used.

[0002]

2. Description of the Related Art As a cooling liquid composition of this type, a freeze-resistant cooling fluid disclosed in JP-A-1-103684 has been known. This fluid comprises 3 to 6 parts by weight of water, 0.5 to 1.5 parts by weight of urea, at most 1.5 parts by weight of glycol, 1-2 parts by weight of sodium formate and 1-2 parts by weight Parts by weight of sodium acetate, or wherein the major components are 4 to 7 parts by weight of potassium acetate, at most 1.5 parts by weight of potassium formate and 3 to 9 parts by weight of water.

[0003] Further, the freeze-resistant cooling fluid may further include:
Preferably, it contains 0.1 to 1.0% by weight of an anticorrosion inhibitor. The anticorrosion inhibitor preferably contains at least one selected from benzoic acid, sodium benzoate, potassium benzoate and benzotriazole.

[0004] The freeze-resistant cooling fluid can be used, for example, in cooling towers of thermal power plants, industrial or household refrigerators and quick freezers, open and closed heat exchangers, solar heat collectors. Activating systems such as multipliers and autoclaves of the chemical industry can prevent freezing failure of the equipment during cooling. Furthermore, it is possible to constitute without containing glycol, and it is possible to improve durability without polluting the environment.

[0005]

However, the conventional freezing-resistant cooling fluid cannot exert a sufficient corrosion-preventing effect mainly on ferrous metals. When the system is operated for a long period of time, the metal constituting the heat exchanger, the pipes, and the connections thereof of the system is corroded to generate corrosion products, which block the pipes and the like. There was a fear.

The present invention has been made by paying attention to the problems existing in the prior art as described above. It is an object of the present invention to provide a coolant composition that can further enhance the corrosion prevention effect while maintaining excellent cooling characteristics.

[0007]

In order to achieve the above object, the coolant composition according to the first aspect of the present invention comprises formic acid and water as main components, and contains 0.1% as an anticorrosive additive.
It is characterized by containing 0.01 to 1.0% by weight of phosphoric acids and 0.01 to 0.5% by weight of a triazole compound.

[0008] The coolant composition of the invention according to claim 2 is
Mainly formate and water, and as anticorrosive additives, aliphatic dicarboxylic acids having 10 to 22 carbon atoms, aliphatic monocarboxylic acids having 7 to 9 carbon atoms, anhydrides and alkali metal salts thereof At least one selected from the group consisting of 0.01
To 5.0% by weight, and 0.01% of the triazole compound.
-10% by weight.

[0009] The coolant composition of the invention according to claim 3 is:
In the invention according to claim 2, the aliphatic dicarboxylic acid is sebacic acid, dodecandioic acid, octenylsuccinic acid, dodecenylsuccinic acid, tetradecenylsuccinic acid, pentadecenylsuccinic acid or octadecenylsuccinic acid. And wherein the aliphatic monocarboxylic acid is enanthic acid, octylic acid or caprylic acid.

[0010] The coolant composition of the invention according to claim 4 is:
The invention according to any one of claims 1 to 3, wherein the triazole compound is tolyltriazole or benzotriazole.

[0011] The coolant composition of the invention according to claim 5 comprises:
The invention according to any one of claims 1 to 4, further comprising 0.01 to 1.0% by weight of a thiazole compound as an anticorrosive additive.

[0012] The coolant composition of the invention according to claim 6 comprises:
The invention according to any one of claims 1 to 5, further comprising 0.01 to 1.0% by weight of boric acids as an anticorrosive additive.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) Hereinafter, a first embodiment of the present invention will be described in detail.

The coolant composition of the first embodiment contains formic acid and water as main components, and also contains a predetermined concentration of phosphoric acid and a triazole compound as an anticorrosive additive. This cooling liquid composition is mainly a refrigerator, an ice machine,
It is used as a low-temperature cooling medium in various other types of cold storage equipment, and is suitably used in a temperature range of about minus 20 to minus 55 ° C. Further, since high cooling characteristics are exhibited even at a relatively high temperature higher than the above temperature range and up to about 100 ° C., it is also used as a cooling liquid medium for cooling a cooling system such as an automobile engine. Can be.

Formate is included in the coolant composition as an antifreeze component. The aqueous solution in which this formate is dissolved can exhibit a very high freezing point depressing action, and the viscosity of the solution does not increase so much even when the aqueous solution is cooled to a low temperature of about −20 to −55 ° C. have. In addition, this formate has little corrosive, volatile and flammable properties.

The formate preferably contains sodium formate or potassium formate, which is an alkali metal salt of formic acid, because of its good solubility in water. Formic acid has a very high solubility in water. Most preferably, it contains potassium. Further, formic acid may be obtained by adding sodium hydroxide or potassium hydroxide to the cooling liquid composition containing formic acid and adjusting the pH.

The concentration of the formate is appropriately determined depending on the temperature range in which the coolant composition is used.
It is preferably contained in a concentration range of 0 to 60% by weight.
If the concentration of this formate is less than 30% by weight, the cooling liquid composition may freeze when cooled to -15 ° C or lower. Conversely, if it exceeds 60% by weight, the cooling liquid composition may not be in a liquid state.

On the other hand, the anticorrosive additive is contained to prevent the corrosion of the metal constituting the heat exchanger, the circulation pipe, the connection part thereof and the like constituting the cooling system in the above-mentioned equipment for keeping cool. In addition, as said metal, cast iron, steel, copper, brass, aluminum, an aluminum alloy, etc. are mentioned.

Phosphoric acids as anticorrosion additives are mainly contained to prevent corrosion of iron-based, copper-based and aluminum-based metals, and include, for example, phosphoric acid, disodium phosphate,
Dipotassium phosphate, sodium hydrogen phosphate, potassium hydrogen phosphate and the like. The phosphoric acids are contained in the coolant composition at a concentration of 0.01 to 1.0% by weight. If the concentration of the phosphoric acid is less than 0.01% by weight, corrosion of iron-based, copper-based, and aluminum-based metals cannot be sufficiently prevented. Conversely, if it exceeds 1.0% by weight, it may not be completely dissolved in the cooling liquid composition.

The triazole compound as an anticorrosion additive is contained mainly for preventing corrosion of copper-based metals, and examples thereof include benzotriazole and tolyltriazole. The triazole compound is contained in the coolant composition at a concentration of 0.01 to 0.5% by weight.
If the concentration of the triazole compound is less than 0.01% by weight, corrosion of the copper-based metal cannot be sufficiently prevented. Conversely, if it exceeds 0.5% by weight, it may not be completely dissolved in the coolant composition.

Furthermore, it is preferable that the coolant composition contains at least one anticorrosive additive selected from thiazole compounds, boric acids and molybdic acids. The thiazole compound is mainly contained in order to more effectively prevent corrosion of the copper-based metal, and examples thereof include mercaptobenzothiazole, and sodium or potassium salts of mercaptobenzothiazole. This thiazole compound is contained in the coolant composition in an amount of 0.01 to 1.0% by weight.
Is preferably contained at a concentration of When the concentration of the thiazole compound is less than 0.01% by weight, corrosion of the copper-based metal cannot be sufficiently prevented. Conversely, if it exceeds 1.0% by weight, it may not be completely dissolved in the cooling liquid composition.

Boric acids are mainly contained to more effectively prevent corrosion of iron-based metals, and examples thereof include boric acid, sodium borate, and potassium borate. The boric acids are present in the cooling liquid composition in an amount of 0.01 to 1.
It is preferably contained at a concentration of 0% by weight. If the concentration of the boric acids is less than 0.01% by weight, the corrosion of the iron-based metal cannot be sufficiently prevented. Conversely, if it exceeds 1.0% by weight, it may not be completely dissolved in the cooling liquid composition.

Molybdates are mainly contained to more effectively prevent corrosion of iron-based metals, and include, for example, molybdate, sodium molybdate and potassium molybdate. The molybdic acids are
It is preferably contained in the coolant composition at a concentration of 0.01 to 1.0% by weight. When the concentration of the molybdic acids is 0.
If it is less than 01% by weight, the corrosion of the iron-based metal cannot be sufficiently prevented. Conversely, if it exceeds 1.0% by weight, it may not be completely dissolved in the cooling liquid composition.

Dyes for coloring the cooling liquid composition such as Food Yellow No. 4, Uranink, Acid Green 25, Phenol Red, etc .; silicone-based antifoaming agents; polyether-based antifoaming agents; It is also possible to add an appropriate combination of an antifoaming agent such as a foaming agent for preventing the generation of foam, or a bitter agent for preventing accidental ingestion such as denatonium benzoate.

Further, in order to enhance the effect of preventing corrosion of the coolant composition, it is preferable to adjust the pH of the coolant composition to 7 to 11. If the pH of the cooling liquid composition is less than 7, corrosion on the iron-based metal may be accelerated. Conversely, if the pH exceeds 11, there is a possibility that corrosion to the copper-based metal is accelerated. In addition, the salts contained in the cooling liquid composition are preferably alkali metal salts because insolubles are not easily generated.

The effects of the first embodiment will be described below. (A) The coolant composition of the first embodiment contains formate and water as main components, and 0.01 to
It contains 1.0% by weight of phosphoric acids and 0.01 to 0.5% by weight of a triazole compound.

Since the formate can exhibit a very high freezing point depressing action and has a very small rise in viscosity of the solution at a low temperature, it can be used as an antifreeze component in a coolant composition. Very suitable. Therefore, this cooling liquid composition can exhibit excellent cooling characteristics due to formate.

Furthermore, the phosphoric acids and triazole compounds contained as the anticorrosive additives have a high corrosion inhibiting effect on iron-based, copper-based and aluminum-based metals, and are therefore composed of these metals. Corrosion to the cooling system can be effectively prevented. For this reason, since corrosion products are not easily generated in the cooling liquid composition, it is possible to effectively prevent clogging of a circulation pipe and the like constituting the cooling system. Therefore, it is possible to use the cooling device for a long period of time with almost no trouble, and it is possible to reduce the labor and cost required for the maintenance of the device.

In addition, since the phosphoric acids are contained at a concentration of 0.01 to 1.0% by weight and the triazole compound is contained at a concentration of 0.01 to 0.5% by weight, a sufficient amount is obtained. In addition to exhibiting a corrosion prevention effect, it can be reliably dissolved in the coolant composition.

(B) On the other hand, since the formate is much less corrosive than calcium chloride which has been conventionally used as an antifreeze component, it further corrodes the metal constituting the cooling system. Can be difficult.

In addition, when compared with ethylene glycol and propylene glycol which have been conventionally used as antifreeze components, the formate can significantly reduce the increase in the viscosity of the solution, and thus can be used in cooling systems. Can be circulated smoothly. For this reason, it is possible to reduce the mechanical load on the circulation pipes and the like that constitute the cooling system, and to reduce the diameter of the circulation pipes (reduce the surface area). It can also be reduced.

Further, since this formate has biodegradability, it is hard to pollute the environment as compared with ethylene glycol and propylene glycol. In addition, the coolant composition of the present embodiment has a chemical oxygen demand (COD) and a biological oxygen demand (B .
OD) can be reduced to 1/20 or less,
The effect of preventing environmental pollution is remarkably high.

In addition, since alcohol-based and fluorine-based compounds conventionally used as antifreeze components have extremely high volatility, it is necessary to frequently replenish the coolant composition in order to compensate for the loss due to volatilization. was there. On the other hand, since the volatility of this formate is extremely low, it is not necessary to frequently replenish the coolant composition, and maintenance can be easily performed.

Further, since the alcohol-based antifreeze component is very flammable, it is necessary to take sufficient measures against fire when designing and manufacturing a cooling system.
On the other hand, since this formate has almost no flammability, it does not require much countermeasures against fire, and can easily design and manufacture a cooling system. Further, this formate can be obtained at a very low cost as compared with a fluorine-based compound.

(C) By adding a thiazole compound as an anticorrosive additive to the cooling liquid composition, the effect of preventing corrosion of copper-based metal can be further enhanced. Further, since the thiazole compound is contained at a concentration of 0.01 to 1.0% by weight, it is possible to exert a sufficient corrosion inhibiting effect and to surely dissolve it in the cooling liquid composition. .

(D) By adding boric acid as an anticorrosion additive to the cooling liquid composition, the effect of preventing corrosion of iron-based metals can be further enhanced. Furthermore, since boric acids are contained at a concentration of 0.01 to 1.0% by weight, a sufficient corrosion inhibiting effect can be exhibited, and the boric acids can be reliably dissolved in the cooling liquid composition. .

(E) By adding molybdic acid as an anticorrosive additive to the cooling liquid composition, the effect of preventing corrosion of iron-based metals can be further enhanced. further,
Since molybdates are contained at a concentration of 0.01 to 1.0% by weight, a sufficient corrosion preventing effect can be exhibited, and the molybdic acids can be reliably dissolved in the coolant composition.

(F) Since potassium formate is contained as a formate, the solubility in water is very good, so that it can be contained in the coolant composition at a very high concentration. For this reason, the cooling characteristics of the cooling liquid composition can be enhanced as much as possible, and it is possible to use the cooling liquid composition at a lower temperature.

(G) The concentration of formate is 30 to 60% by weight
By doing so, the cooling characteristics of the cooling liquid composition can be reliably improved. (H) By adjusting the pH of the cooling liquid composition to 7 to 11, the effect of preventing corrosion of iron-based and copper-based metals can be further improved.

(I) By making the salt contained in the cooling liquid composition an alkali metal salt, it is possible to make it difficult to generate insoluble matters and to further enhance the corrosion prevention effect. (Second Embodiment) A second embodiment of the present invention will be described focusing on differences from the first embodiment.

The cooling liquid composition of the second embodiment contains formic acid and water as main components, and as an anticorrosion additive, an aliphatic dicarboxylic acid having 10 to 22 carbon atoms, and a 7 to 9 carbon atoms.
At least one selected from aliphatic monocarboxylic acids, anhydrides and alkali metal salts thereof, from 0.01 to 5.0.
% By weight, and 0.01 to 1.0% of the triazole compound.
% By weight. This coolant composition is mainly used as a coolant medium for cooling a cooling system of an automobile engine or the like. For example, the coolant composition can prevent freezing even at a low temperature of 0 to −55 ° C., and has a temperature of 0 to 100 ° C.
High cooling characteristics can be exhibited even at relatively high temperatures. Further, similarly to the first embodiment, it can be used as a cooling liquid medium for cooling equipment for keeping cool.

The formate is contained as an antifreeze component to lower the freezing point of the coolant composition, and serves to prevent the coolant composition from freezing and destroying a cooling system such as an automobile engine. do. The concentration of this formate is appropriately determined depending on the temperature range in which the cooling liquid composition is used, but is preferably 20 to 60% by weight, more preferably 30 to 60% by weight. If the concentration of this formate is less than 20% by weight, the cooling liquid composition may freeze when cooled to -10 ° C or lower. Conversely, if it exceeds 60% by weight, the cooling liquid composition may not be in a liquid state.

The anticorrosion additive is contained for suppressing corrosion of metals including aluminum, aluminum alloy, cast iron, steel, brass, solder, copper, etc. constituting a cooling system of an automobile engine or the like.

Aliphatic dicarboxylic acids having 10 to 22 carbon atoms, aliphatic monocarboxylic acids having 7 to 9 carbon atoms, anhydrides thereof and alkali metal salts thereof (hereinafter referred to as aliphatic carboxylic acids) as anticorrosive additives. Has an excellent corrosion prevention effect mainly on iron-based, copper-based and aluminum-based metals.

Examples of the aliphatic dicarboxylic acids having 10 to 22 carbon atoms include sebacic acid, dodecandioic acid, octenyl succinic acid, dodecenyl succinic acid, tetradecenyl succinic acid, pentadecenyl succinic acid, octadecedic acid and the like. Nil succinic acid. If the aliphatic dicarboxylic acid has less than 10 carbon atoms, the effect of preventing corrosion of the metal is significantly reduced. Conversely, when the number of carbon atoms exceeds 22, it is not preferable because the solubility is significantly reduced.

On the other hand, examples of the aliphatic monocarboxylic acid having 7 to 9 carbon atoms include enanthic acid, octylic acid,
And caprylic acid. When the aliphatic monocarboxylic acid has less than 7 carbon atoms, it is difficult to handle because of high volatility. Conversely, when the carbon number exceeds 9,
It is not preferable because the solubility is significantly reduced.

The concentration of the aliphatic carboxylic acids is 0.0
Within the range of 1 to 5.0% by weight, preferably 0.5 to
It is within the range of 5.0% by weight. When the concentration of the aliphatic carboxylic acid is less than 0.01% by weight, a sufficient corrosion inhibitory effect cannot be exerted on the metal. On the other hand, if it exceeds 5.0% by weight, it may not be completely dissolved in the cooling liquid composition.

The concentration of the triazole compound as an anticorrosion additive is from 0.01 to 1.0% by weight, preferably from 0.01 to 0.5% by weight. If the concentration of the triazole compound is less than 0.01% by weight, corrosion of the copper-based metal cannot be sufficiently prevented. Conversely, if it exceeds 1.0% by weight, it may not be completely dissolved in the cooling liquid composition.

Further, it is preferable to add a dissolving agent for improving the solubility of the anticorrosive additive to the cooling liquid composition. As the dissolving agent, for example, ethylene glycol or propylene glycol is preferably used because it is easily available and hardly causes a decrease in cooling characteristics.
The concentration of this solubilizer is preferably 1 to 10% by weight, more preferably 1 to 5% by weight. If the concentration of this solubilizer is
When the amount is less than the weight percentage, the solubility of the anticorrosion additive cannot be sufficiently increased. Conversely, if it exceeds 10% by weight, the viscosity of the cooling liquid composition will increase.

Further, it is preferable that the coolant composition contains at least one anticorrosive additive selected from thiazole compounds, boric acids and molybdic acids. Dyes for coloring the coolant composition such as Edible Yellow No. 4, Uranink, Acid Green 25, and Phenol Red, silicone-based antifoaming agents, polyether-based antifoaming agents, and polymer alcohol-based antifoaming agents It is also possible to add an appropriate combination of an antifoaming agent for preventing the generation of foam, or a bitter agent for preventing accidental ingestion, such as denatonium benzoate.

Further, in order to enhance the corrosion prevention effect of the coolant composition, it is preferable to adjust the pH of the coolant composition to 7 to 11 as in the first embodiment. In addition, the salts contained in the cooling liquid composition are preferably alkali metal salts because insolubles are not easily generated.

The effects exerted by the second embodiment will be described below. The coolant composition of the second embodiment contains formate and water as main components and has 10 carbon atoms as an anticorrosive additive.
0.01 to 5.0% by weight of at least one selected from aliphatic dicarboxylic acids having from 22 to 22, aliphatic monocarboxylic acids having from 7 to 9 carbon atoms, anhydrides and alkali metal salts thereof,
And 0.01 to 1.0% by weight of a triazole compound. Therefore, as in the first embodiment, excellent cooling characteristics can be exhibited by the formate.

Further, the aliphatic carboxylic acids and triazole compounds contained as anticorrosion additives are iron-based,
It has a high corrosion inhibiting effect on copper-based and aluminum-based metals. Therefore, similarly to the first embodiment, it is possible to use a cooling system such as an automobile engine for a long period of time with almost no trouble, and to reduce the labor and cost required for the maintenance. .

On the other hand, the aliphatic dicarboxylic acids, their anhydrides and their alkali metal salts have a high corrosion inhibiting effect on aluminum and aluminum alloys particularly in cooling systems under high temperature and high flow rate conditions. Blackening of the metal surface can be prevented. Further, the aliphatic monocarboxylic acid, its anhydride, and its alkali metal salt have a high corrosion inhibiting effect on the metal, are available at low cost, and are easy to handle because they are liquid.

In addition, the amount of the aliphatic carboxylic acid is from 0.01 to
Since the triazole compound is contained at a concentration of 5.0% by weight and the triazole compound is contained at a concentration of 0.01 to 1.0% by weight, a sufficient anticorrosion effect can be exhibited and the cooling liquid It can be reliably dissolved in the composition. (B) described in the first embodiment.
The same effect as described above is also exhibited.

On the other hand, since this cooling liquid composition does not contain phosphorus, which is a main cause of water pollution, for example, rivers, oceans, and the like pass through ordinary drains without proper treatment of waste liquid. Even if the water leaks into the water, it is unlikely to cause malicious water pollution and the load on the environment can be reduced.

As the aliphatic carboxylic acids, sebacic acid, dodecandioic acid, octenylsuccinic acid, dodecenylsuccinic acid, tetradecenylsuccinic acid, pentadecenylsuccinic acid, octadecenylsuccinic acid, enanthic acid, octylic acid, By using at least one selected from caprylic acid, its anhydride and its alkali metal salt, the effect of preventing corrosion of the coolant composition can be easily and reliably increased. Further, by using tolyltriazole or benzotriazole as the triazole compound, the effect of preventing corrosion of the coolant composition can be more easily enhanced. Further, the cooling liquid composition of the present embodiment exhibits the same effects as (c) to (i) described in the first embodiment.

[0058]

EXAMPLES Examples and comparative examples which embody the above embodiment will be described below. The percentages described below are
Unless otherwise indicated, the percentages are by weight.

(Examples 1 to 5) After mixing the components (%) shown in Table 1, for Examples 2 to 5, cooling was performed by adjusting the pH of the solution to about 8.5 using caustic potassium. A liquid composition was prepared. According to the method described in JIS K 2234, these coolant compositions were used after 2 weeks (described as 2w in the table) and after 4 weeks (described as 4w in the table) of the metal test piece. Yes)
Was measured for the amount of corrosion (mg / cm ² ). Details of the test conditions are described below.

Test piece: copper, brass, steel, aluminum casting Test temperature: 40 ° C. Liquid volume: 750 ml Aeration condition: 100 ml / min The above test temperature is expected to be the strictest condition for the cooling liquid composition solution. 40 ° C., which is the temperature to be performed (when the operation of the cold storage device in the summer is stopped) was selected. Table 1 shows the results.

[0061]

[Table 1] (Comparative Examples 1 to 4) After mixing the components (%) shown in Table 2, the pH of the solution was adjusted to about 8.5 with caustic potassium to prepare a cooling liquid composition. For these coolant compositions, the corrosion amount (mg / cm ² ) of the metal test piece was measured in the same manner as in the tests of Examples 1 to 5.
Table 2 shows the results.

[0062]

[Table 2] From the results of Tables 1 and 2, the coolant compositions of Examples 1 to 5 have significantly reduced amounts of corrosion of copper, brass, steel and aluminum castings as compared with the coolant compositions of Comparative Examples 1 to 4. Has been shown.

(Examples 6 to 10 and Comparative Examples 5 to 8) Table 3
Then, after mixing the components (%) shown in Table 4, the pH of the solution was adjusted to about 9.0 with caustic potassium to prepare a coolant composition. According to the method described in JIS K 2234, these coolant compositions were used after 2 weeks (described as 2w in the table) and after 4 weeks (described as 4w in the table) of the metal test piece. Yes)
Was measured for the amount of corrosion (mg / cm ² ). The details of the test conditions are described below, and the results are shown in Table 3.
And Table 4 below.

Test piece: copper, brass, steel, aluminum casting, cast iron, solder Test temperature: 88 ° C. Liquid volume: 750 ml Aeration condition: 100 ml / min

[0065]

[Table 3]

[0066]

[Table 4] From the results in Tables 3 and 4, the coolant compositions of Examples 6 to 10 were compared with the coolant compositions of Comparative Examples 5 to 8 in corrosion of copper, brass, steel, aluminum casting, cast iron, and solder. The amount was shown to be significantly reduced.

The above embodiment can be embodied with the following modifications. -Use of the coolant composition of the first embodiment as a cooling medium for cooling a cooling system such as an automobile engine. Alternatively, the cooling liquid composition of the second embodiment is
Use it as a low-temperature coolant medium for ice machines and other various types of cold storage equipment. Even with such a configuration, the corrosion prevention effect can be further enhanced while exhibiting excellent cooling characteristics.

Further, the technical ideas that can be grasped from the above embodiment will be described below. (1) at least one selected from the group consisting of aliphatic dicarboxylic acids having 10 to 22 carbon atoms, aliphatic monocarboxylic acids having 7 to 9 carbon atoms, anhydrides thereof, and alkali metal salts thereof; 7. The composition according to claim 2, which contains 0% by weight.
The cooling liquid composition according to any one of the above. With such a configuration, the effect of preventing corrosion can be further improved.

(2) The cooling liquid composition according to any one of (2) to (6) and (1), further comprising a solubilizer for increasing the solubility of the anticorrosive additive. With such a configuration, the effect of preventing corrosion of the coolant composition can be significantly improved.

(3) The cooling liquid composition according to (2), wherein the dissolving agent is ethylene glycol or propylene glycol, and the concentration of the dissolving agent is 1 to 10% by weight. With such a configuration, it is possible to prevent the deterioration of the cooling characteristics by suppressing the increase in the viscosity while increasing the effect of preventing the corrosion of the coolant composition.

(4) Further, 0.01 as an anticorrosive additive
The cooling liquid composition according to any one of claims 1 to 6, and (1) to (3), which contains 1.0 to 1.0% by weight of molybdic acids. With this configuration, the effect of preventing corrosion of iron-based metal can be further enhanced.

(5) The cooling liquid composition according to any one of (1) to (6) and (1) to (4), wherein the formate is potassium formate. With such a configuration, it can be contained in the coolant composition at a very high concentration, and the cooling properties of the coolant composition can be improved.

(6) The coolant composition according to any one of (1) to (6) and (1) to (5), which contains the formate in a concentration of 30 to 60% by weight. With this configuration, the cooling characteristics of the cooling liquid composition can be improved.

(7) The cooling liquid composition according to any one of (1) to (6) and (1) to (6), wherein the pH of the solution is 7 to 11. With this configuration,
The effect of preventing corrosion of iron-based and copper-based metals can be further enhanced.

(8) At least one selected from the group consisting of phosphoric acids, thiazole compounds, boric acids and molybdic acids is an alkali metal salt.
And the coolant composition according to any one of (1) to (7). With such a configuration, generation of insolubles can be effectively suppressed, and the corrosion prevention effect can be further enhanced.

(9) The cooling liquid medium for cooling the cooling equipment is used as a cooling liquid medium.
And the cooling liquid composition according to any one of (4) to (8). In the case of such a configuration, it is possible to further enhance the corrosion prevention effect while exhibiting excellent cooling characteristics for the device for keeping cool.

(10) The method according to any one of (2) to (6) and (1) to (7), wherein the cooling medium is used as a cooling medium for cooling a cooling system of an automobile engine. Coolant composition. With this configuration, the corrosion prevention effect can be further enhanced while exhibiting excellent cooling characteristics for the cooling system of the automobile engine.

[0078]

As described above in detail, according to the present invention, the following effects can be obtained. According to the coolant composition of the invention described in claims 1 and 2, it is possible to further enhance the corrosion prevention effect while exhibiting excellent cooling characteristics.

According to the coolant composition of the third aspect, in addition to the effect of the second aspect, the effect of preventing corrosion can be easily enhanced. According to the coolant composition of the invention described in claim 4, in addition to the effect of the invention described in any one of claims 1 to 3, the corrosion prevention effect can be more easily enhanced.

According to the coolant composition of the invention described in claim 5, in addition to the effect of the invention described in any one of claims 1 to 4, the effect of preventing corrosion of copper-based metal is further enhanced. Can be.

According to the cooling liquid composition of the invention described in claim 6, in addition to the effects of the invention described in any one of claims 1 to 5, the effect of preventing corrosion of iron-based metal is further enhanced. Can be.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3L044 AA04 BA09 CA03 DB02 DD07 KA01 4K062 AA03 BA08 BB18 BB22 DA01 FA05 GA01 GA08

Claims (6)

[Claims] 1. A composition comprising formate and water as main components,
A coolant composition comprising 0.01 to 1.0% by weight of a phosphoric acid and 0.01 to 0.5% by weight of a triazole compound as an anticorrosive additive. 2. A composition comprising formate and water as main components,
As an anticorrosion additive, at least one selected from aliphatic dicarboxylic acids having 10 to 22 carbon atoms, aliphatic monocarboxylic acids having 7 to 9 carbon atoms, anhydrides thereof, and alkali metal salts thereof is 0.01 to 5 A cooling liquid composition containing 0.0% by weight and 0.01 to 1.0% by weight of a triazole compound. 3. The aliphatic dicarboxylic acid is sebacic acid, dodecane diacid, octenyl succinic acid, dodecenyl succinic acid, tetradecenyl succinic acid, pentadecenyl succinic acid or octadecenyl succinic acid. The cooling liquid composition according to claim 2, wherein the group monocarboxylic acid is enanthic acid, octylic acid, or caprylic acid. 4. The cooling liquid composition according to claim 1, wherein the triazole compound is tolyltriazole or benzotriazole. 5. The anticorrosive additive of 0.01 to 1.
5. The coolant composition according to claim 1, comprising 0% by weight of the thiazole compound. 6. The anticorrosive additive of 0.01 to 1.
The coolant composition according to any one of claims 1 to 5, comprising 0% by weight of boric acids.