JPH08277481A - Water-based rust preventive - Google Patents

Abstract

PURPOSE: To obtain a rust preventive having excellent safety which gives an enough rust preventing effect when used with a low concn. by using a compd. having a carboxyalkyl thiosuccinate skeleton and its salt. CONSTITUTION: This rust preventive consists of one of (A) a compd. expressed by formula, (B) a salt prepared by neutralizing the compd. (A) with a basic compd., (C) a hydrated condensate of the compd. expressed by formula I with at least one compd. selected from alcohols, ammonia and amines, and (D) a salt prepared by neutralizing the dehydrated condensate (C) with a basic compd. The basic compd. used for neutralization is preferably at least one compd. selected from metal hydroxides, metal carbonates, ammonia and 1-30C amines. A single compd. among (A)-(D) or a mixture of two or more compds. of these may be used for the rust preventive, and it is prepared as an aq. soln. or water dispersion of 0.01-10wt.% concn., preferably 0.05-5wt.% concn. for use.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an aqueous rust preventive agent.
More specifically, the present invention relates to a water-based rust preventive agent that is added to water to prevent metal rusting.

[0002]

2. Description of the Related Art Conventionally, water-based anticorrosive agents have been widely used for corrosion prevention in the fields of metal working products, steam generators, coolers, chemical devices, piping, building materials, civil engineering, and the like. Water-based rust inhibitors are roughly classified into inorganic rust inhibitors such as chromates, nitrites and phosphates, and organic rust inhibitors such as various amine salts, carboxylates and carboxylic acid amides. Classified and both are in use. However, inorganic anticorrosive agents are often not preferable from the viewpoint of safety and environmental protection. For example, chromate is highly toxic, nitrite has a risk of producing nitrosamine, and phosphate is a cause of eutrophication of rivers and lakes. In order to solve these problems, for example, organic rust preventives such as carboxylic acid salts as disclosed in JP-B-57-59309 and carboxylic acid amides as disclosed in JP-A-60-116791. Agents have been proposed. These organic rust preventives have been improved with respect to the above-mentioned safety, but on the other hand, since the adsorptivity or affinity to the metal surface is small, the rust preventive property is particularly sufficient in the low concentration region. I can't say.

[0003]

The present invention has been made with the object of providing an aqueous rust preventive agent which has no problem in terms of safety and has an excellent rust preventive effect even in a low concentration in water. is there.

[0004]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found that a compound having a carboxyalkylthiosuccinic acid skeleton and a salt thereof have an excellent anticorrosive effect. The present invention has been completed and the present invention has been completed based on this finding. That is, the present invention is
(1) (A) A water-based rust preventive comprising a compound represented by the following general formula [1] or a salt of the compound represented by the following general formula [1] neutralized with a (B) basic compound,

Embedded image (In the formula, R is an alkylene group having 1 to 30 carbon atoms.) (2) (A) A compound represented by the following general formula [1] and (C) 1 selected from alcohol, ammonia and amine. A dehydration condensate with one or more compounds, or (A) a dehydration condensate with a compound represented by the following general formula [1] and (C) one or more compounds selected from alcohols, ammonia and amines (B) ) A water-based rust preventive comprising a salt neutralized with a basic compound,

[Chemical 4] (However, in the formula, R is an alkylene group having 1 to 30 carbon atoms.) And (3) (B) the basic compound is a metal hydroxide, a metal carbonate, ammonia or 1 to 10 carbon atoms.
No. 1, which is one or more compounds selected from 30 amines
The water-based rust preventive agent according to item (1) or (2) is provided. In the general formula [1], R is 1 to 1 carbon atoms.
It is an alkylene group of 30 and may be linear or branched. Examples of such an alkylene group include a methylene group, an ethylene group, a propylene group, a trimethylene group, a butylene group, a tetramethylene group,
Examples thereof include a pentylene group, a hexylene group, an octylene group, a decylene group, a pentadecylene group, an octadecylene group, an eicosylene group, a pentacosylene group and a triacontylene group. Of these alkylene groups, a methylene group, an ethylene group and a propylene group are particularly preferable. One embodiment of the water-based rust preventive agent of the present invention comprises (A) a compound represented by the general formula [1] or a salt obtained by neutralizing the compound represented by the general formula [1] with a (B) basic compound. It will be. In this embodiment, the compound represented by the general formula [1] can be used as an aqueous rust preventive by diluting it with water as it is. However, depending on the kind of metal for which rust is desired to be prevented, the compound represented by the general formula [1] can be used. Since the compound may cause acid corrosion in some cases, it is usually preferable to neutralize with a basic compound (B) and use it as a salt.

In the present invention, examples of the basic compound (B) for forming a salt include ammonia, metal hydroxides, metal carbonates and amines. It can be used particularly preferably. Examples of the metal forming the metal hydroxide and the metal carbonate include, for example, lithium, sodium, potassium, calcium, magnesium, zinc, aluminum,
Although iron, cobalt, nickel, copper, tin, cadmium, barium and the like can be mentioned, among these, lithium, sodium, potassium, calcium, magnesium, zinc and aluminum are preferable. Examples of amines include aliphatic amines having 1 to 30 carbon atoms and 6 carbon atoms.
To 30 aromatic amines, C2 to C30 amino alcohols, and the like. Examples of such amines include methylamine, ethylamine, butylamine,
Aliphatic amines such as octylamine, dodecylamine, octadecylamine, dimethylamine, diethylamine, dioctylamine, ditetradecylamine, methyldodecylamine, butyloctylamine, triethylamine, tributylamine, tri (2-ethylhexyl) amine, ethylenediamine, Aliphatic polyamines such as diethylenetriamine, triethylenetetramine and hexamethylenediamine, aromatic amines such as aniline, methylaniline, ethylaniline, dodecylaniline and methylbenzylamine, heterocyclic amines such as pyrrolidine, piperidine, morpholine and pyridine, mono Examples thereof include amino alcohols such as ethanolamine, diethanolamine, and triethanolamine. Of these, aliphatic amines having 1 to 18 carbon atoms and 2-1 to 2 carbon atoms
An aliphatic polyamine having 8 and an amino alcohol having 2 to 18 carbon atoms can be particularly preferably used. In the present invention, the neutralization of the compound represented by the general formula [1] is 1
One kind of basic compound can be used alone, or two or more kinds of basic compound can be mixed and used. Further, in the present invention, the neutralization of the compound represented by the general formula [1] can be a partial neutralization for neutralizing a part of the carboxyl group of the compound represented by the general formula [1]. Alternatively, it can be a complete neutralization for neutralizing all the carboxyl groups of the compound represented by the general formula [1].

Another aspect of the water-based rust preventive agent of the present invention is
(A) A dehydration condensation product of the compound represented by the general formula [1] and (C) one or more compounds selected from alcohol, phenol, ammonia and amine, or the dehydration condensation product (B) a basic compound It consists of salt neutralized with. In the reaction of the compound represented by the general formula [1] with the component (C), an ester is used when an alcohol is used as the component (C), a phenyl ester is used when a phenol is used, and an ammonia is used. An amide or imide is formed in the amide, and an amide or imide is formed in the case of using an amine. Since the compound represented by the general formula [1] has three carboxyl groups, a partially dehydrated condensate or a salt thereof, an ester and an amide, an ester and an imide, a compound having an amide and an imide, or a salt thereof can be prepared. Therefore, a rust preventive agent having an appropriate structure can be selected according to the intended use. To neutralize the dehydrated condensate of the compound represented by the general formula [1] and one or more compounds selected from alcohol, phenol, ammonia and amine, the compound represented by the general formula [1] can be used. The basic compounds used for neutralization can be used exactly as well. In the present invention, the alcohol used as the component (C) is an aliphatic alcohol having 1 to 30 carbon atoms and 7 carbon atoms.
-30 aromatic alcohols and the like can be mentioned.
Such alcohols include, for example, methanol,
Saturated aliphatic monohydric alcohols such as ethanol, propanol, butanol, hexanol, octanol, decanol, dodecanol, tetradecanol, hexadecanol, octadecanol, eicosanol, cyclohexanol, allyl alcohol, butenyl alcohol, hexenyl alcohol, oct. Unsaturated aliphatic monohydric alcohols such as tenyl alcohol, nonenyl alcohol, decenyl alcohol, dodecenyl alcohol, tetradecenyl alcohol, hexadecenyl alcohol, octadecenyl alcohol, ethylene glycol, propylene glycol , Polyethylene glycol, polypropylene glycol, 1,4-butanediol, 1,6-hexanediol, glycerol, trimethylolpropane, pentaerythritol, Pentaerythritol, sorbitan, polyhydric alcohols such as sorbitol, benzyl alcohol, alkyl benzyl alcohols having 8 to 30 carbon atoms, alkenyl benzyl alcohol 9-30 carbon atoms,
Examples thereof include aromatic alcohols such as alkylphenol alkylene oxide adducts. Among these, aliphatic alcohols having 1 to 30 carbon atoms are preferable, and aliphatic alcohols having 1 to 24 carbon atoms are more preferable, from the viewpoints of economy and ease of reaction control when synthesizing the water-based rust preventive agent. These alcohols form an ester by dehydration condensation with the carboxyl group of the compound represented by the general formula [1].

In the present invention, examples of the phenol used as the component (C) include phenol, alkylphenol having 7 to 30 carbon atoms, alkenylphenol having 8 to 30 carbon atoms, resorcinol and the like. These phenols form a phenyl ester by dehydration condensation with the carboxyl group of the compound represented by the general formula [1]. In the present invention, as the amine used as the component (C), an aliphatic amine having 1 to 30 carbon atoms and 1 carbon atom
-30 aromatic amines and the like can be mentioned. Examples of such amines include aliphatic amines such as methylamine, ethylamine, butylamine, octylamine, dodecylamine, octadecylamine, dimethylamine, diethylamine, dioctylamine, ditetradecylamine, methyldodecylamine and butyloctylamine. , Aliphatic diamines such as ethylenediamine, diethylenetriamine, triethylenetetramine, and hexamethylenediamine, aromatic amines such as aniline, and the like. Among these, the carbon number is 1 to 1 because of economy and ease of reaction control when synthesizing the water-based rust preventive agent.
An aliphatic amine having 30 is preferable, and an aliphatic amine having 1 to 24 carbon atoms is more preferable. These amines form an amide or imide by dehydration condensation with the carboxyl group of the compound represented by the general formula [1]. Therefore, the tertiary amine can be used as the basic compound of the component (B), but cannot be used as the component (C).
In the present invention, as the component (C), an alkanolamine having properties of both alcohol and amine, for example,
Monoethanolamine, diethanolamine, triethanolamine, isopropanolamine, N-methylethanolamine and the like can be used. These alkanolamines form an ester by dehydration condensation with the compound represented by the general formula [1], or form an amide or an imide depending on the reaction conditions and the kind of the selected alkanolamine. Of these, alkanolamines, which are tertiary amines such as triethanolamine, are dehydrated and condensed with the compound represented by the general formula [1] as an alcohol, not as an amine.

(A) General formula [1] of the water-based rust preventive agent of the present invention
In the production by reacting the compound represented by the formula (C) with the component (C), the molar ratio of the compound represented by the general formula [1] and the component (C) to be used is not particularly limited. It is preferable to charge the compound of the component (C) in an amount of 0.05 to 100 mol and to perform dehydration condensation with respect to 1 mol of the carboxyl group of the compound to be prepared, and to add 0.1 to 30 mol of the compound of the component (C) to perform dehydration condensation. More preferably. actually,
The compound of the component (C) does not react in excess of 1 mol with respect to 1 mol of the carboxyl group of the compound represented by the general formula [1], but a polyvalent compound as the component (C), for example, When using polyols, polyamines, etc.,
In order to prevent the system from becoming non-uniform due to partial polyesterification or polyamidization, and when a low-boiling compound such as ammonia, methanol, ethanol or propanol is used as the component (C), water generated For the purpose of facilitating the removal of the compound and shortening the reaction time, more than 1 mol of the compound of the component (C) is charged to 1 mol of the carboxyl group of the compound represented by the general formula [1] as described above. It may be preferred. Even in such a case, the carboxyl group 1 of the compound represented by the general formula [1]
If the amount of the component (C) compound exceeds 100 moles, the effects on homogenization of the system, removal of produced water, shortening of reaction time, etc. are not further observed, which is economically disadvantageous. . As described above, in order to facilitate the reaction operation, even when the component (C) is used in a stoichiometric amount or more, after the reaction, or after neutralization with the basic compound (B),
Although it can be used as the water-based rust preventive agent of the present invention, if an unreacted component (C) remains in a too large amount, the concentration of the active ingredient of the water-based rust preventive agent of the present invention is substantially reduced to improve the rust preventive effect. Since it causes the decrease, it is preferable to remove the unreacted component (C) by a treatment such as distillation after the dehydration-condensation reaction or after the neutralization in an economically feasible range.

In the present invention, when the compound represented by the general formula [1] and the compound of the component (C) are subjected to dehydration condensation reaction,
A completely dehydrated condensate in which all three carboxyl groups of the compound represented by the general formula [1] are dehydrated and condensed by adjusting the amount of the compound (C) used and the reaction conditions.
It is possible to obtain any partially dehydrated condensate in which at least one of the three carboxyl groups of the compound represented by the general formula [1] remains unreacted. The water-based rust inhibitor of the present invention,
In the case of the above complete dehydration condensate, the compound of the component (C) used preferably has 8 or less carbon atoms.
The following is more preferable. When the compound of the component (C) has more than 8 carbon atoms, the completely dehydrated condensate has a low solubility in water and has poor water solubility or self-emulsification property, and is sufficiently emulsified by mechanical force to be an aqueous dispersion. There is a possibility that rust prevention performance may not be exhibited. When the water-based rust preventive agent of the present invention is the partial dehydration condensation product described above, it has sufficient rust preventive performance, but it may cause acid corrosion depending on the metal with which the carboxyl group remains, so that it remains. The carboxyl group is preferably neutralized with a basic compound (B) and used as a salt. The basic compound (B) used for neutralization is 1
The seeds may be used alone or in combination of two or more. Further, the neutralization of the remaining carboxyl groups may be partial neutralization for neutralizing a part of the remaining carboxyl groups, or may be complete neutralization for neutralizing all of the remaining carboxyl groups. it can.
The method for synthesizing the water-based rust preventive agent of the present invention is not particularly limited, and a known synthesis method can be used. For example, by reacting maleic acid with mercaptocarboxylic acid or by reacting maleic anhydride with mercaptocarboxylic acid and hydrolyzing the obtained reaction product, a compound represented by the general formula [1] Can be obtained. The compound represented by the general formula [1] can be obtained by the known method (B).
It can be neutralized with a basic compound. A compound represented by the general formula [1] and an alcohol as a component (C),
When phenol, ammonia or amine is reacted, and a carboxyl group remains, it can be neutralized with the basic compound (B). Alternatively, a mercaptocarboxylic acid, a mercaptocarboxylic acid ester, a mercaptocarboxylic acid derivative such as a mercaptocarboxylic acid amide can be added to a maleic acid derivative such as a maleic acid ester, a maleic acid amide, a maleic acid imide, or a maleic acid alkylamide. Furthermore, when a carboxyl group remains in the addition product, it can be neutralized with the basic compound (B).

In the present invention, the salt of the compound represented by the general formula [1] neutralized with the basic compound (B) is a compound represented by the general formula [2].

Embedded image (However, in the formula, R is an alkylene group having 1 to 30 carbon atoms.) Is reacted in an aqueous medium in the presence of the (B) basic compound, and hydrolysis and neutralization are simultaneously performed. Obtainable. In the present invention, the dehydration condensation product of the compound represented by the general formula [1] and the compound (C) selected from alcohol, ammonia and amine is a compound represented by the general formula [2].

[Chemical 6] (In the formula, R is an alkylene group having 1 to 30 carbon atoms.) And (C) a compound selected from alcohol, ammonia, and amine are reacted to open the succinic anhydride structure and, at the same time, react with a carboxyl group. It can also be obtained by preparing a compound having a structure in which one of the groups is dehydrated and condensed with a compound selected from alcohol, ammonia and amine.

Specifically, for example, maleic anhydride, mercaptopropionic acid in a solvent such as toluene, and a tertiary amine such as triethylamine as a catalyst are used in a proportion of 50 to 1: 1.
After reacting at a temperature of about 50 ° C. for about 0.5 to 10 hours to add, the obtained addition product is purified by recrystallization to obtain carboxyethylthiosuccinic anhydride. The resulting carboxyethylthiosuccinic anhydride can be neutralized in water with sodium hydroxide, calcium carbonate, zinc hydroxide, ammonia, amines and the like. Moreover, the obtained carboxyethylthiosuccinic anhydride and a carbon number of 1 to 3
0 alcohols such as methanol, ethanol, cyclohexanol, benzyl alcohol, 2-ethylhexanol, lauryl alcohol, oleyl alcohol, stearyl alcohol, glycerin, sorbitan,
Polyethylene glycol, triethanolamine and the like can be reacted and esterified by a known esterification method to obtain a partially esterified product or triesterized product of carboxyethylthiosuccinic acid. The partial esterified product of carboxyethylthiosuccinic acid can be neutralized with a metal hydroxide, ammonia, amine or the like, if necessary. Carboxyethylthiosuccinic anhydride is ammonia or amine having 1 to 30 carbon atoms, for example, methylamine, dimethylamine, ethylamine, diethylamine, butylamine, octylamine, methyloctylamine, dodecylamine, stearylamine,
Oleylamine and the like can be reacted by a known amidation method or imidization method to amidate or imidize a part or all of the carboxyl groups. The partial amidated product, the partially imidized product, or the partially amidimidated product can be further neutralized with a metal hydroxide, ammonia, amine or the like, if necessary.

The water-based rust preventive agent of the present invention utilizes the above-mentioned esterification reaction, amidation reaction, imidization reaction, and neutralization reaction in this order in order to form an ester bond, an amide bond, an imide bond in one molecule. By using a carboxyethylthiosuccinic acid derivative having a bond, an ester bond and an amide bond, an ester bond and an imide bond, or an amide bond and an imide bond, compounds having various structures depending on the application can be obtained. Incidentally, the triamide compound is usually difficult to synthesize because it is preceded by the imidization reaction of the succinic acid residue of carboxyethylthiosuccinic acid, and there is a problem in economic efficiency, but it is included in the technical scope of the present invention. Needless to say. The water-based rust preventive of the present invention is preferably used as an aqueous solution or dispersion of 0.01 to 10% by weight,
It is more preferable to use it as an aqueous solution or dispersion of 0.05 to 5% by weight. Concentration of water-based rust inhibitor is 0.01
If it is less than wt%, the rust preventive effect may be insufficient. When the concentration of the water-based rust preventive agent exceeds 10% by weight, the rust preventive effect is not improved in proportion to the increase in the concentration of the water rust preventive agent, which may be economically disadvantageous. The water-based rust preventive agent of the present invention can be used alone, or can be used by mixing two or more kinds of the water-based rust preventive agent of the present invention, and further, within a range not impairing the object of the present invention. Then, the water-based rust preventive agent of the present invention and a known water-based rust preventive agent can be used in combination. The use of the water-based rust preventive agent of the present invention is not particularly limited, for example, water, alcohol aqueous solution, aqueous antifreeze, radiator cooling water, aqueous solutions of water-soluble metal working oil agents, resin emulsions, mineral oil emulsions, animal and vegetable oil emulsions. ,
It can be added and used for improving the rust-preventive property of an aqueous emulsion such as an emulsion type water-based metalworking oil.

[0013]

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Production Example 1 Carboxyethylthiosuccinic acid (20.4 g) was dissolved in 300 g of water, neutralized with morpholine until the pH reached 7.5, and diluted with water until the solid content reached 5% by weight. An aqueous solution of an aqueous rust preventive agent in which R in the formula [1] was an ethylene group and was neutralized with morpholine was obtained. Production Examples 2 to 5 In the same manner as in Production Example 1, the carboxyalkylthiosuccinic acid having R shown in Table 1 is neutralized with the basic compound shown in Table 1, and the solid content becomes 5% by weight. Was diluted with water to obtain an aqueous solution or dispersion of an aqueous rust preventive agent. Production Example 6 Carboxyethylthiosuccinic acid 222.2 g (1 mol)
And 2-ethylhexanol (273.5 g, 2.1 mol) were added to an esterification catalyst of paratoluenesulfonic acid (0.1%).
Put it in a 1-liter four-necked flask together with 4 g and carry out an esterification reaction at 140 ° C. for 10 hours while removing water generated under a nitrogen atmosphere to obtain a crude product of di (2-ethylhexyl) ester of carboxyethylthiosuccinic acid. 460
g was obtained. The crude product was vacuum dried at 100 ° C. for 3 hours,
Unreacted 2-ethylhexanol was removed to obtain 407 g of a purified product of di (2-ethylhexyl) ester of carboxyethylthiosuccinic acid. As a result of measuring the acid value of this purified esterified product, it was found that 1.2 mol of carboxyl groups remained in 1 mol of the esterified product. 10 g of this purified esterified product was added to 200 g of water and neutralized with morpholine until the pH reached 7.5, and R in the general formula [1] was an ethylene group, and 2-ethylhexanol left a residual carboxyl group per molecule. A 5% by weight aqueous solution of an aqueous rust preventive which was esterified to an average of 1.2 and neutralized with morpholine was prepared. Production Examples 7 to 14 In the same manner as in Production Example 6, the carboxyalkylthiosuccinic acid having R shown in Table 1 was subjected to dehydration condensation reaction with the alcohol, ammonia, amine shown in Table 1 or a mixture thereof. Table 1 shows the number of residual carboxyl groups obtained by measuring the acid value. Further, the obtained compound was neutralized with the basic compounds shown in Table 1 so as to have a pH of 7.5, to prepare an aqueous solution or dispersion of an aqueous rust preventive agent having a solid content of 5% by weight.

[0014]

[Table 1]

Example 1 A 5 wt% aqueous solution of the water-based rust preventive obtained in Production Example 1 was diluted,
Aqueous solutions having concentrations of 0.05% by weight, 0.2% by weight and 2% by weight were prepared. 3 cm × washed and degreased in this aqueous solution
5 cm cold-rolled steel plate test piece SPCC-B (JIS G 3
After immersing the whole of 141), the upper half of the test piece was pulled up into the air and kept at 20 ° C., and after 4 days and 15 days,
The generation state of rust after 30 days and 45 days was visually observed. In a test using an aqueous solution having a concentration of 0.05% by weight, no rust was observed until 15 days later, but
After 2 days, rust occurred in 2% of the total area, and after 45 days, rust occurred in 5% of the total area. The rust prevention performance was expressed using the following criteria according to the ratio of the area of rust to the total area of the test piece, and the results are shown in Table 2. ⊚: No rust is observed. ◯: The area ratio of rust is less than 10%. Δ: The area ratio of rust is 10% or more and less than 30%. X: The area ratio of rust is 30% or more and less than 50%. XX: The area ratio of rust is 50% or more. Examples 2 to 14 Using the 5% by weight aqueous solution or dispersion of the water-based rust preventives obtained in Production Examples 2 to 14, respectively, in the same manner as in Example 1, the concentrations were 0.05% by weight, 0.2% by weight and A 2% by weight aqueous solution or an aqueous dispersion was prepared and tested for antirust performance. The results are shown in Table 2. Comparative Example 1 A rust preventive performance test was conducted in the same manner as in Example 1 using lauric acid morpholine salt as an aqueous rust preventive agent. The results are shown in Table 2. Comparative Example 2 A rust preventive performance test was conducted in the same manner as in Example 1 using triethanolamine citrate as an aqueous rust preventive.
The results are shown in Table 2. Comparative Example 3 A rustproofing performance test was conducted in the same manner as in Example 1 using a commercially available carboxylate amine-based waterborne rustproofing agent. Second result
Shown in the table. Comparative Example 4 A rust preventive performance test was conducted in the same manner as in Example 1 using a commercially available nitrite-based water-based rust preventive agent. The results are shown in Table 2. Comparative Example 5 The occurrence of rust was examined in the same manner as in Example 1 using water instead of the aqueous solution of the water-based rust preventive agent. The results are shown in Table 2.

[0016]

[Table 2]

[0017]

[Table 3]

From the results shown in Table 2, the water-based rust preventives of the present invention (Examples 1 to 14) are the conventional carboxylic amine salts (Comparative Examples 1 to 2) and the commercially available water-based rust preventives (Comparative Example 3). ~ 4)
It was found that even when the concentration was low, it showed excellent rust prevention performance.

[0019]

Industrial Applicability The water-based rust preventive agent of the present invention exhibits excellent rust preventive performance at a low concentration without causing problems of safety and environmental pollution, and can prevent the occurrence of metal rust. it can.

Claims (3)

[Claims] 1. A compound represented by the following general formula [1] or a compound represented by the following general formula [1] (B):
A water-based rust preventive consisting of a salt neutralized with a basic compound. Embedded image (However, in the formula, R is an alkylene group having 1 to 30 carbon atoms.) 2. A dehydrated condensate of (A) a compound represented by the following general formula [1] and (C) one or more compounds selected from alcohols, ammonia and amines, or (A) the following general formula [ 1] and a compound (C) alcohol,
An aqueous rust preventive agent comprising a salt obtained by neutralizing a dehydration condensation product with one or more compounds selected from ammonia and amine with a basic compound (B). Embedded image (However, in the formula, R is an alkylene group having 1 to 30 carbon atoms.) 3. The (B) basic compound is a metal hydroxide,
The water-based rust preventive agent according to claim 1 or 2, which is one or more compounds selected from metal carbonates, ammonia and amines having 1 to 30 carbon atoms.