KR20040093331A - Composition material of antifreeze - Google Patents

Abstract

PURPOSE: An antifreeze composition is provided, which can prevent a gel-stability and an anticorrosive property of aluminium from lowering when the antifreeze composition reacts chemically with a flux remaining from a process forming tubes of a radiator and a heater core. CONSTITUTION: The antifreeze composition contains 85-97wt% of ethylene glycol, 0.1-10wt% of sodium benzoate, 0.1-4.0wt% of an imidazole, 0.1-4.0wt% of nitrobenzoic acid, 0.1-1.0wt% of a nitrate, 0.01-1wt% of a silicate stabilizer represented by the formula: R1-CH=CH-CH2-CH-CH2, 0.001-0.4wt% of an antifoaming agent, 0.1-3.0wt% of an alkali metal hydroxide, 0.01-1wt% of a scale preventing agent represented by the formula: £CH-CH|n, and water. In the formulas, R1 and R2 are identically or differently C1-C10 alkyl, R3 is C1-C5 alkyl, and n is an integer of 100-10,000.

Description

Antifreeze composition {Composition material of antifreeze}

The present invention relates to an antifreeze composition, and more particularly, to the formation of a gel while preventing the formation of a gel and a corrosion protection effect of the flux and the silicate additive of the antifreeze remaining when the tube of the radiator and the heater core are molded. It relates to an antifreeze composition that can be improved.

In general, the antifreeze is a cooling medium that releases heat generated by combustion and friction of the internal combustion engine to the outside, and serves to maintain the cooling efficiency while acting as a freezing prevention, metal corrosion prevention, bubble generation suppression and oxidation prevention of non-metallic materials.

Recent corrosion inhibitors include hexanoic acid (caproic acid), heptanoic acid (heptanoic acid), octanoic acid (Nctanoic acid), nonanoic acid, decanoic acid, and undecanoic acid. Aliphatic monocarboxylic acid, and aliphatic dicarboxylic acid corrosion such as adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, etc. Many inhibitors have been reported.

The dicarboxylic acid-based corrosion inhibitors such as sebacic acid and azelaic acid are known from US Patent No. 2,726,215, UK Patent No. 1,004,259, French Patent No. 2,489,355, and the like, and US Patent No. 4,759,864 and US Patent No. 5,269,956. European Patent No. 564721, European Patent No. 552988, US Patent No. 4,869,841, US Patent No. 4,647,392, US Patent No. 4,454,050, and the like.

However, the above known technique has a corrosion resistance under limited conditions, and the occurrence of precipitation, gelation of silicates, and corrosion resistance of aluminum and solder are poor due to flux remaining in the tube when forming tubes of hard water, radiators, and heater cores. There was a problem that the anticorrosive effect of the solder is lowered as the amount of aliphatic carboxylic acid additive is increased in a high temperature environment.

In addition, the US Patent No. 5,290,469, US Patent No. 5,320,771, US Patent No. 4,676,919, etc., which are introduced to have excellent corrosion protection under light water conditions, to the effect of the flux remaining when forming the tube of the radiator or heater core The anticorrosive effect of silicate antifreeze has not been proven.

On the other hand, the silicate is accelerated generation of the gel in the presence of high temperature and salts to reduce the corrosion protection performance of US Patent No. 4,485,026, US Patent No. 5,064,552, US Patent No. 4,772,408, US Patent No. 3,198,820, etc. There is no mention of fluxes, which are used or stabilizer compounds, but fluxes, which are gel-inducing factors present in the cooling system, have not been proposed to solve problems that may arise in the automotive cooling system.

Therefore, an object of the present invention is to solve the above problems, the flux remaining in the tube when forming the tube of the radiator and the heater core is eluted by the high temperature state and physical and chemical action with the additive, It is to provide an antifreeze composition that can effectively prevent the phenomenon of deteriorating the gel stability by reducing the gel stability while the ionic chemical action with the silicate.

In order to achieve the above object, the present invention provides 85 to 97% by weight of ethylene glycol, 0.1 to 10% by weight of sodium benzoate, 0.1 to 4.0% by weight of imidazole, 0.1 to 4.0% by weight of nitrobenzoic acid, 0.1 to 1.0% by weight of nitrate, An antifreeze composition comprising 0.01 to 1% by weight of a silicate stabilizer, 0.001 to 0.4% by weight of an antifoaming agent, 0.1 to 3.0% by weight of an alkali metal hydroxide, 0.01 to 1% by weight of a scale inhibitor, and water.

And the silicate stabilizer is a compound of Formula 1, and the scale inhibitor is a compound of Formula 2.

R1-CH = CH-CH2-CHC-CH2

｜ ｜

O = C C = O

｜ ｜

HO S-R2-Si (ＯＲ3) 3

In Formula 1, R1 and R2 are the same as or different from each other, and C1 to C10 represent an alkyl group, and R3 represents an alkyl group of C1 to C5.

[CＨ-ＣＨ] n

｜ ｜

O = C C = O

｜ ｜

ＨＯ ＯＨ

N in the formula (2) represents an integer of 100 to 10,000.

Hereinafter, the present invention will be described in detail.

That is, the present invention is characterized in that the composition containing the silicate stabilizer of formula (1) and the scale inhibitor of formula (2) do not contain any aliphatic mono and dicarboxylic acid which causes gel when used with silicate as a composition having excellent flux resistance.

Here, sodium benzoate is preferably added in an amount of 0.1 to 10% by weight and 0.6 to 5.0% by weight, and when it is less than 0.1% by weight, it is difficult to exhibit anticorrosive performance. Stability issues can occur.

In the case of imidazole, it is preferable to use 0.1 to 5.0% by weight and add 0.1 to 3.0% by weight, and when the amount is less than 0.1% by weight, it is difficult to act as an anticorrosive function and a pH buffer function of the iron system, If you use it, the economy is poor.

In addition, in the case of nitrobenzoic acid, it is preferable to use 0.1 to 4.0% by weight and add 0.1 to 3.0% by weight, and using 0.1% by weight may cause problems in corrosion resistance to cast iron and solder materials, and 4.0% by weight or more. If you use it, the stability of the liquid will be reduced and the liquid may discolor.

In addition, it is preferable to use 0.1 to 1.0% by weight and add 0.1 to 0.8% by weight of nitrate. When 0.1% by weight or less is used, it is difficult to exhibit solder and aluminum anticorrosive performance, and when 0.8% by weight or more is used, solder and copper system are used. It can adversely affect the corrosion resistance of, and can be used in the form of sodium and potassium salts.

In addition, benzotriazole, tolyltriazole, and the like may be used as the triazole salt. When 0.01 to 2.0% by weight is used, and when 0.01% by weight or less is used, the copper anticorrosive property is lowered. Can lower the anticorrosive performance.

In addition, the silicate is preferably used in an amount of 0.1 to 1.0% by weight, and added in an amount of 0.1 to 0.6% by weight. If it is less than 0.1% by weight, it causes corrosion of aluminum, and when it exceeds 1.0% by weight, gelation results in poor corrosion resistance to aluminum. While the gel can cause various problems inside the cooling engine.

In addition, the silicate stabilizer of the formula (1) of the present invention is preferably used 0.01 to 1.0% by weight, preferably 0.01 to 0.8% by weight, less than 0.01% by weight is difficult to act as a gel stabilizer, if more than 0.8% by weight May cause corrosion of the iron system, and the stability and economy of the liquid is poor.

And antifoaming agent to prevent foaming during the circulation in the automotive cooling system using 0.001 to 0.4% by weight, when using more than that may cause precipitation and cloudiness in the liquid.

In addition, to adjust the pH of the antifreeze composition in the range of 7 to 10, sodium hydroxide, potassium hydroxide, or the like may be used to use 0.1 to 3.0% by weight of the alkali metal hydroxide.

In addition, the scale inhibitor represented by the formula (2) is preferably added in an amount of 0.01 to 1% by weight in order to suppress the occurrence of precipitation in the water of high hardness. Or discoloration of liquid and the balance of anticorrosive performance.

The following describes the embodiments to better understand the present invention, and the conditions specified in these examples are described for the purpose of explanation only, and the present invention is not limited to the embodiments.

Component (wt%) Example 1 Example 2 Example 3 Ethylene glycol 91.788 90.613 4.0 Sodium benzoate 2.0 1.5 4.0 Nitrobenzoic acid 1.4 2.0 0.8 Imidazole 1.5 2.0 1.0 Benzotriazole 2.0 - 0.1 Tolyltriazole - 0.3 0.1 H ₂ O 2.0 2.0 2.0 Sodium silicate 0.15 0.20 0.25 Silicate Stabilizer (1) 0.02 0.025 0.030 Potassium hydroxide - 0.84 0.43 Sodium hydroxide 0.62 - - Sodium nitrate 0.3 0.5 0.4 Antiscaling Agent (2) 0.02 0.02 0.02 Antifoam (3) 0.002 0.002 0.002

(1) is a compound of Formula 1

(2) is a compound of formula 2

(3) Lucky D silicon silicone DB-110A

Component (wt%) Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Ethylene glycol 91.568 90.033 91.175 90.678 90.573 Sodium benzoate 2.0 1.5 3.0 4.0 2.5 Sebacic acid 1.0 0.8 Adipic acid 0.4 0.7 2-ethylhexanoic acid 2.0 Octanoic acid 1.0 Heptanoic acid 0.8 Succinic acid 1.0 Imidazole 1.5 2.0 1.8 1.0 1.6 Benzotriazole 0.2 0.2 0.1 Tolyltriazole 0.3 0.2 H ₂ O 2.0 2.0 2.0 2.0 2.0 Sodium silicate 0.15 0.20 0.18 0.25 0.30 Silicate Stabilizer (5) 0.02 0.025 (8) 0.023 (9) 0.03 0.035 Potassium hydroxide 0.62 Sodium hydroxide 0.84 0.72 0.35 0.87 Sodium nitrate 0.3 0.5 0.25 0.4 0.2 Antiscaling Agent (6) 0.02 0.02 0.02 0.02 0.02 Antifoam (7) 0.002 0.002 0.002 0.002 0.002

(5) is a compound of Formula 1

(6) is a compound of Formula 2

(7) Lucky D Silicone Silicone DB-110A

(8) and (9) Ukasil AF-1

Next, in order to evaluate the influence of the flux with respect to the antifreeze composition Table 1 and Comparative Example antifreeze composition Table 2, the high-temperature storage stability test, ASTM aluminum heat transfer surface test, cyclic corrosion test was evaluated.

Here, the high temperature storage stability test was performed for 0.2 days in 0.2 g / l of flux melted at 600 ° C. for 30 minutes at 90 ° C. and 110 ° C., respectively, and water / antifreeze = 50/50 concentration for 14 days.

And ASTM aluminum heat transfer test was tested for the generation of flocculated precipitates and suspended solids by putting 0.2g / ℓ of flux in the ASTM combination water 25vol% test solution and 135 ℃, 193Kpa, 168hr test.

In addition, the circulation corrosion resistance test was carried out at a concentration of 45% of the ASTM combination water and 0.2g / ℓ of flux in the test solution and tested at 98 ℃ 1000 hours.

Therefore, the following shows the test results for the Examples and Comparative Examples through Table 3, Table 4, Table 5.

High Temperature Storage Stability Test Results Example Comparative example One 2 3 One 2 3 4 5 90 ℃ With flux 14 days <- <- 6-day gel generation 5 days gel generation 6-day gel generation 5 days gel generation 4 days gel generation Without flux 14 days <- <- 14 days <- <- <- <- 110 ℃ With flux 14 days <- <- 4 days gel generation 3-day gel generation 4 days gel generation 3-day gel generation Without flux 14 days <- <- 14 days 11 days gel generation 14 days 10 days gel production 12 days gel generation

ASTM Aluminum Heat Transfer Test Results Example Comparative example One 2 3 One 2 3 4 5 With flux State of solution after test No gel <- <- Gel Generation <- <- <- <- Specimen weight change rate (mg / ㎠ / 7 days) -0.38 -0.44 -0.57 -1.42 -1.10 -0.95 -1.70 -0.92 Plus not included State of solution after test No gel <- <- <- <- <- <- <- Specimen weight change rate (mg / ㎠ / 7 days) +0.10 -0.16 -0.21 -0.62 +0.24 -0.48 -0.66 -0.54

Cyclic Corrosion Test Results Example Comparative example One 2 3 One 2 3 4 5 With flux State of solution after test No gel <- <- Gel Generation <- <- <- <- Weight change rate Aluminum casting ± 0.60 -0.08 -0.07 -0.10 -0.28 -0.35 -0.41 -0.32 -0.38 cast iron ± 0.30 -0.09 -0.14 -0.08 -0.27 -0.25 -0.18 -0.22 -0.26 River ± 0.30 -0.05 -0.06 +0.04 -0.08 -0.09 -0.10 -0.06 -0.08 Brass ± 0.30 +0.11 +0.09 -0.08 -0.18 -0.22 -0.27 -0.16 -0.09 pewter ± 0.60 -0.08 -0.10 -0.09 -0.31 -0.45 -0.36 -0.46 -0.40 Copper ± 0.30 -0.06 -0.05 +0.07 -0.21 -0.26 -0.15 -0.26 -0.12 Without flux State of solution after test No gel <- <- <- <- <- <- <- Weight change rate Aluminum casting ± 0.60 -0.05 -0.03 -0.07 -0.08 -0.07 -0.14 -0.10 -0.09 cast iron ± 0.30 -0.06 -0.08 -0.06 -0.10 -0.10 -0.07 -0.08 -0.05 River ± 0.30 -0.03 -0.04 +0.02 -0.05 -0.03 -0.05 -0.03 -0.02 Brass ± 0.30 +0.06 +0.05 -0.08 -0.08 -0.07 -0.09 -0.13 -0.15 pewter ± 0.60 -0.06 -0.07 -0.08 -0.15 -0.12 -0.16 -0.18 -0.10 Copper ± 0.30 -0.07 -0.07 +0.08 -0.07 -0.06 -0.10 -0.12 -0.14

The cyclic corrosion test of Table 5 is a test to increase the temperature to 98 ℃ with a test solution in order to minimize the influence of the flux remaining during the heater core and radiator molding before the test, completely discharge the liquid after 2 hours circulation, and several times after filling the new solution It was.

As can be seen in Table 3, Table 4, and Table 5, the composition according to the embodiment of the present invention maintained a normal quality excellent in corrosion resistance without generating a gel even in the presence of flux, The composition according to the comparative example containing the marked difference in the quality of the presence or absence of the flux, and the presence of the flux, the gel generation rate is increased, the problem of discoloration, corrosion and weight change rate of the test piece increases.

As described above, in the present invention, even though the flux remaining in the process of forming the tube of the radiator and the heater core and the antifreeze made of the composition according to the present invention have a chemical action at a high temperature, the gel stability is deteriorated. It is possible to effectively prevent the phenomenon that the anticorrosive performance is reduced.

Claims (11)

The antifreeze composition comprising glycol, sodium benzoate, nitrobenzoic acid, imidazole, triazoles, sodium silicate, sodium nitrate, and metal hydroxide in the composition of the antifreeze composition. The antifreeze composition according to claim 1, wherein the compound according to Formula 1 is contained in an amount of 0.01 to 1 wt%. [Formula 1] R1-CH = CH-CH2-CHC-CH2 ｜ ｜ O = C C = O ｜ ｜ HO S-R2-Si (ＯＲ3) 3 The antifreeze composition according to claim 2, wherein R1 contains a C1 to C10 alkyl group. The antifreeze composition according to claim 2, wherein R2 contains a C1 to C10 alkyl group. The antifreeze composition according to claim 2, wherein R3 contains a C1 to C5 alkyl group. The antifreeze composition according to claim 1, wherein the compound according to Formula 2 is contained in an amount of 0.01 to 1 wt%. [Formula 2] [CＨ-ＣＨ] n ｜ ｜ O = C C = O ｜ ｜ ＨＯ ＯＨ 7. The antifreeze composition according to claim 6, wherein n represents an integer of 100 to 1000. The method according to claim 1, wherein 0.1 to 10% by weight of sodium benzoate, 0.1 to 5.0% by weight of imidazole, 0.01 to 1.0% by weight of sodium silicate, 0.01 to 2.0% by weight of tolyltriazole, 0.01 to 2.0% by weight of benzotriazole, nitrobenzoic acid Antifreeze composition characterized by using one or more selected from the group consisting of 0.1 to 4.0% by weight, sodium nitrate, 0.1 to 1.0% by weight of potassium nitrate, 0.001 to 0.4% by weight of antifoaming agent. The method according to claim 1, wherein 85 to 97% by weight of the water-soluble liquid glycols are made by using one or two or more in the crowd of ethylene glycol, diethylene glycol, triethylene glycol, phosphoethylene glycol, dipropylene glycol, butylene glycol. Antifreeze composition characterized in. 2. The antifreeze composition of claim 1, further comprising an amount of alkali metal hydroxide sufficient to adjust the composition pH between 7 and about 10. 2. The antifreeze composition of claim 1, further comprising an amount of water sufficient to provide an amount of 1 to 95% by weight of water present in the composition.