Rust-preventive composition

Abstract

To provide a rust-preventive agent that forms a coating layer having superior transparency and superior removability, and that exhibits long-term rust prevention performance.SOLUTION: A rust-preventive composition comprises a lubricating base oil (A), a rust-preventive additive (B), and a sulfonic acid metal salt (C). The weight ratio (B) / (A) of the rust-preventive additive (B) to the lubricating base oil (A) is 0.07 to 3. The weight ratio (C) / (A) of the sulfonic acid metal salt (C) to the lubricating base oil (A) is 0.4 to 7.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a rust preventive composition used for corrosion prevention of metals.

Background Art

[0002] A rust preventive agent is applied to the underbody of a vehicle body such as an automobile, parts around the wheels, cavities, the inside of doors and bonnets, welded parts, and panel joints to prevent rust. This is because steel materials used in automobiles and the like have a serious drawback of rust. Steel materials and the like are exposed to an environment where rust is likely to occur due to moisture caused by rainfall or high humidity, salt wind containing salt, and antifreeze agents such as calcium chloride and sodium chloride. The problem of how to prevent such rust has become a very important issue in industries that handle steel materials, such as the automotive industry.

[0003] As a rust preventive agent currently commonly used, a rust preventive agent mainly composed of wax is known. As such a wax-based rust preventive agent, a composition mixed with microcrystalline wax, paraffin wax, metal salts of natural fatty acids, petroleum sulfonates, and mineral spirits is mainstream (see Patent Documents 1 to 4).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, although such conventional wax-based rust preventives are excellent in rust prevention properties, the coating film may be opaque and may impair the appearance of the substrate. In addition, when demolding, it is necessary to rub off using a strong solvent, an alkaline detergent, etc., and it is often relatively difficult to remove the rust preventive scattered around during coating. Considering the load on the human body, the demolding target member, the environment, etc., there is a demand for a rust preventive composition that can be easily demolded with a neutral detergent having a weaker removal ability than an alkaline detergent.

[0006] As a result of intensive studies in view of the above problems, the present inventors have found a composition that forms a coating film excellent in transparency and having excellent demolding properties and exhibits long-term rust prevention power. The present invention has been completed through further studies based on the above findings.

Means for Solving the Problems

[0007] That is, the present invention relates to the following (1) to (6). (1) A rust preventive composition containing a base oil (A), a rust preventive additive (B), and a metal sulfonate (C), wherein the weight ratio of the base oil (A) to the rust preventive additive (B) is (B) / (A)=0.08 to 2.5, and the weight ratio of the base oil (A) to the metal sulfonate (C) is (C) / (A)=0.4 to 5.5. (2) The rust preventive composition according to (1) above, wherein the rust preventive additive (B) is a rust preventive additive (B) containing at least one of the structures of Chemical Formulas 1 and 2 below. Chemical Formula 1:

Chemical

Chemical

[0008] By using the rust preventive agent of the present invention, it is possible to form a coating film having excellent transparency and excellent film release properties. In addition, it is possible to exhibit rust preventive power over a long period of time. [Embodiments for Carrying Out the Invention]

[0009] The rust preventive agent according to this embodiment contains a base oil (A), a rust preventive additive (B), and a metal sulfonate (C) as main components. The method for manufacturing the rust preventive agent according to this embodiment is carried out by charging each raw material, heating and dissolving it, cooling it to room temperature, and stirring it using a stirrer.

[0010] The base oil (A) used in this embodiment is a liquid at room temperature (25 °C). The kinematic viscosity of the base oil is represented by the viscosity classification defined in ISO 3448 (JIS K2001:1993). This viscosity classification is classified by the kinematic viscosity mm 2 / s (cst) at 40 °C of the base oil and is commercially available in the notation of the ISO VG (Viscosity Grade) number. In this embodiment, the kinematic viscosity of the base oil at 40 °C is a value measured using a glass capillary viscometer in accordance with JIS K2283:2000.

[0011] The kinematic viscosity of the base oil at 40 °C used in this embodiment is not particularly limited, but for example, those in the range of 3 to 1000 mm 2 / s are preferred. If the kinematic viscosity of the base oil at 40 °C is too high, the demolding property may decrease. Conversely, if it is too low, the viscosity of the rust preventive composition may decrease, and the paintability such as sagging may decrease. Therefore, 10 to 680 mm 2 / s is more preferred, and 46 to 500 mm 2 / s is even more preferred. The kinematic viscosity of the base oil at 40 °C used as component (A) may be within the above range when used alone or when two or more are mixed. Even if the kinematic viscosity of a single base oil at 40 °C is outside the above range, it can be used as long as the kinematic viscosity of the base oil after mixing is within the above range.

[0012] The base oil (A) used in this embodiment can be used without particular limitation as long as it is generally a base oil for industrial lubricants. For example, mineral oils, synthetic oils, etc. can be used. These can be used alone or in combination of two or more. Examples of mineral oils include paraffinic oils and naphthenic oils. These mineral oils may be refined oils obtained by sulfuric acid washing, clay treatment, vacuum distillation, solvent refining, hydrotreating, or the like. Generally, paraffinic oils have a paraffin carbon number (%CP) of 50% or more in ring analysis by the n-d-M method, and naphthenic oils have a naphthene carbon number (%NP) of 30% or more. Examples of synthetic oils include poly-α-olefins, polybutenes, alkylbenzenes, alkylnaphthalenes, cycloalkanes, GTL (Gas to Liquids) oils produced by the Fischer-Tropsch method, phosphate esters, polyoxyalkylene glycols, polyoxyalkylene glycol ethers, phenyl ethers, halocarbons, silicone oils, and the like. Among mineral oils and synthetic oils, considering the stable presence in the coating film as base oil (A) and enhancing the release property and rust prevention property, hydrocarbon base oils that do not contain heteroatoms such as oxygen atoms, nitrogen atoms, and sulfur atoms, namely, paraffinic oils, naphthenic oils, poly-α-olefins, polybutenes, alkylbenzenes, alkylnaphthalenes, and cycloalkanes are particularly preferred.

[0013] The rust prevention additive (B) used in this embodiment is a carboxylic acid-based rust prevention additive different from sulfonates containing at least one of the structures shown in Chemical Formulas 1 and 2. R1 is a hydrocarbon group, for example, a hydrocarbon group having 8 to 36 carbon atoms, which may be a saturated hydrocarbon group or an unsaturated hydrocarbon group, may be linear or branched, and may contain an alicyclic ring or an aromatic ring. Further, a part of the hydrocarbon group of R1 may be substituted with a hydroxy group, an ether group, a ketone group, a carboxy group, an amino group, or the like. R2 is any one of hydrogen, an alkali metal, an alkaline earth metal, and a hydrocarbon group. Examples of the alkali metal include lithium, sodium, potassium, etc., and examples of the alkaline earth metal include magnesium, calcium, barium, etc. The hydrocarbon group of R2 includes, for example, a hydrocarbon group having 1 to 36 carbon atoms, which may be a saturated hydrocarbon group or an unsaturated hydrocarbon group, may be linear or branched, and may contain an alicyclic or aromatic ring. A part of the hydrocarbon group of R2 may be substituted with a hydroxy group, an ether group, a ketone group, a carboxy group, an amino group, etc. R3, R4, and R5 are hydrogen or a hydrocarbon group. When R3, R4, and R5 are hydrocarbon groups, similar to the hydrocarbon group of R1, they may be a saturated hydrocarbon group or an unsaturated hydrocarbon group, may be linear or branched, and may contain an alicyclic or aromatic ring. Also, a part of the hydrocarbon groups of R3, R4, and R5 may be substituted with a hydroxy group, an ether group, a ketone group, a carboxy group, an amino group, etc.

[0014] As the rust preventive additive (B) used in this embodiment, a carboxylic acid-based rust preventive additive different from sulfonate can be used. For example, conventionally known carboxylic acid, metal carboxylate, carboxylic acid ester, carboxylic acid amine salt, oxidized wax, metal oxidized wax, oxidized wax ester, oxidized wax amine salt, oxidized petrolatum, metal oxidized petrolatum, oxidized petrolatum ester, oxidized petrolatum amine salt can be used. These may be used alone or in combination of two or more.

[0015] Examples of the above carboxylic acid include carboxylic acids having 9 to 36 carbon atoms, such as fatty acids, dicarboxylic acids, naphthenic acids, aromatic carboxylic acids, hydroxycarboxylic acids, lanolin fatty acids, etc. The carboxylic acid may be a saturated carboxylic acid or an unsaturated carboxylic acid, may be a linear carboxylic acid or a branched-chain carboxylic acid, may contain an alicyclic or aromatic group, and may be a carboxylic acid containing a hydroxy group, an ether group, a ketone group, a carboxy group, an amino group, etc.

[0016] Examples of the above fatty acids include linear saturated fatty acids such as nonanoic acid, decanoic acid, dodecanoic acid, tetradecanoic acid, hexadecanoic acid, heptadecanoic acid, octadecanoic acid, arachidic acid, behenic acid, and lignoceric acid; linear unsaturated fatty acids such as myristoleic acid, palmitoleic acid, oleic acid, elaidic acid, petroselinic acid, gadolenic acid, eicosenoic acid, erucic acid, nervonic acid, linoleic acid, eicosadienoic acid, docosadienoic acid, linolenic acid, and arachidonic acid; branched-chain fatty acids such as 2-butyloctanoic acid, isostearic acid, and 2-octyldodecanoic acid; dicarboxylic acids such as dodecanedioic acid, 2-butyloctanedioic acid, tetradecanedioic acid, pentadecanedioic acid, hexadecanedioic acid, heptadecanedioic acid, octadecanedioic acid, eicosanedioic acid, docosanedioic acid, tetracosanedioic acid, hexacosanedioic acid, octacosanedioic acid, triacontanedioic acid, alkyl succinic acid, alkenyl succinic acid, and dimer acid obtained by dimerization of unsaturated fatty acids; carboxylic acids containing an alicyclic structure such as naphthenic acid; aromatic carboxylic acids such as alkylbenzoic acid and alkylnaphthalenecarboxylic acid; and hydroxycarboxylic acids such as 2-hydroxyhexadecanoic acid, 12-hydroxystearic acid, and ricinoleic acid.

[0017] The above lanolin fatty acids are carboxylic acids obtained by saponifying and decomposing the wax attached to wool, and are usually a mixture mainly composed of linear carboxylic acids, branched carboxylic acids, hydroxycarboxylic acids, etc. with 9 to 34 carbon atoms.

[0018] Among the above carboxylic acids, oleic acid, ricinoleic acid, stearic acid, naphthenic acid, alkenyl succinic acid, dimer acid obtained by dimerization of unsaturated fatty acids, and lanolin fatty acids are preferred, and oleic acid, stearic acid, and lanolin fatty acids are more preferred.

[0019] The metal carboxylate can be obtained by reacting the above carboxylic acid with a base such as a metal oxide or hydroxide as a raw material. Examples of the metal species used in the metal carboxylate include alkali metals such as lithium, sodium, and potassium, alkaline earth metals such as magnesium, calcium, and barium, and zinc. Considering enhancing the rust prevention property, alkaline earth metals such as magnesium, calcium, and barium are preferable, calcium and barium are more preferable, and calcium is even more preferable.

[0020] The carboxylic acid ester can be obtained by reacting the above carboxylic acid with alcohols as a raw material. Examples of the alcohols include linear or branched saturated monohydric alcohols having 1 to 36 carbon atoms, linear or branched unsaturated monohydric alcohols having 1 to 36 carbon atoms, polyhydric alcohols preferably having 2 to 10 hydroxy groups in the molecule and having 2 to 36 carbon atoms, lanolin alcohol obtained by hydrolysis of lanolin, and the like. The ester of the carboxylic acid and the polyhydric alcohol may be a partial ester in which at least one hydroxy group of the polyhydric alcohol remains, or a full ester in which all hydroxy groups of the polyhydric alcohol are esterified. Among them, the alcohols are more preferably trimethylolethane, trimethylolpropane, sorbitan, pentaerythritol, glycerin, and diglycerin, and sorbitan and pentaerythritol are even more preferable.

[0021] Examples of the oxidized wax include those obtained by introducing hydroxy groups, carbonyl groups, carboxy groups, etc. into mineral waxes such as paraffin wax and microcrystalline wax classified according to JIS K2235-2022, synthetic waxes such as Fischer-Tropsch wax, polyethylene wax, and polypropylene wax by air oxidation or the like.

[0022] The metal salt of oxidized wax is obtained by reacting the above-mentioned oxidized wax with a base such as a metal oxide or hydroxide. Examples of the metal species used in the metal salt of oxidized wax include alkali metals such as lithium, sodium, and potassium, alkaline earth metals such as magnesium, calcium, and barium, and zinc. Considering enhancing the rust prevention property, alkaline earth metals such as magnesium, calcium, and barium are preferred, calcium and barium are more preferred, and calcium is even more preferred.

[0023] The oxidized wax ester is obtained by reacting the above-mentioned oxidized wax with alcohols. As the alcohols, those mentioned in the above carboxylic acid esters can be similarly used. Among them, esters with linear or branched saturated monohydric alcohols having 1 to 18 carbon atoms are more preferred.

[0024] Examples of oxidized petrolatum include those obtained by introducing hydroxy groups, carbonyl groups, carboxy groups, etc. into petrolatum (a semi-solid wax at room temperature separated and purified from vacuum distillation residual oil classified according to JIS K2235 - 2022) by air oxidation or the like.

[0025] The metal salt of oxidized petrolatum is obtained by reacting the above-mentioned oxidized petrolatum with a base such as a metal oxide or hydroxide. Examples of the metal species used in the metal salt of oxidized petrolatum include alkali metals such as lithium, sodium, and potassium, alkaline earth metals such as magnesium, calcium, and barium, and zinc. Considering enhancing the rust prevention property, alkaline earth metals such as magnesium, calcium, and barium are preferred, calcium and barium are more preferred, and calcium is even more preferred.

[0026] The acidified petrolatum ester is obtained by reacting the above-mentioned acidified petrolatum with alcohols as raw materials. As the alcohols, those exemplified for the above-mentioned carboxylic acid esters can be similarly used. Among them, esters with linear or branched saturated monohydric alcohols having 1 to 18 carbon atoms are more preferable.

[0027] The carboxylic acid amine salts, oxidized wax amine salts, and oxidized petrolatum amine salts can be obtained by reacting amines with raw materials such as the above-mentioned carboxylic acids, oxidized waxes, oxidized petrolatums, etc. In this embodiment, the above amine salts may be those previously neutralized as amine salts, or may be used as amine salts during the manufacturing process, such as dissolving carboxylic acids in a solvent or base oil and then neutralizing with amines to prepare amine salts. Examples of amines include primary amines such as ethylamine, n-propylamine, butylamine, 1-ethylbutylamine, 2-ethylhexylamine, octylamine, 1,3-diaminopropane, cyclohexylamine, secondary amines such as diethylamine, dibenzylamine, di-n-propylamine, diethylenetriamine, tetraethylenepentamine, coconut oil alkyldimethylamine, dimethyl(tallow alkyl)amine, tertiary amines such as dimethylethylamine, diethylmethylamine, triethylamine, tributylamine, polyamines such as ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, propylenediamine, dipropylenetriamine, tripropylenetetramine, tetrapropylenepentamine, pentapropylenehexamine, butylenediamine, dibutylenetriamine, tributylenetetramine, tetrabutylenepentamine, pentabutylenehexamine, N-alkyl ethylenediamines such as N-methylethylenediamine, N-ethylethylenediamine, N-propylethylenediamine, N-alkenyl ethylenediamines such as N-vinyl ethylenediamine, N-propenyl ethylenediamine, N-butenyl ethylenediamine, N-alkyl or N-alkenyl alkylene polyamines such as N-alkyl diethylenetriamine, N-alkenyl diethylenetriamine, N-alkyl triethylenetetramine. Among these, 2-ethylhexylamine, octylamine, tributylamine, trioctylamine, coconut oil alkyldimethylamine, and dimethyl(tallow alkyl)amine are more preferred.

[0028] Among them, considering enhancing the rust prevention property, the rust prevention additive (B) is preferably an aliphatic metal salt, fatty acid ester, oxidized wax metal salt, oxidized wax ester, oxidized petrolatum metal salt, or oxidized petrolatum ester having high adhesion to the metal substrate. Fatty acid metal salts, oxidized wax metal salts, and oxidized petrolatum metal salts are more preferable, and calcium fatty acid salts, calcium oxidized wax salts, and calcium oxidized petrolatum salts are even more preferable.

[0029] The sulfonic acid metal salt (C) used in this embodiment includes, for example, petroleum sulfonate obtained by sulfonating and neutralizing the aromatic hydrocarbon component contained in mineral oil, and synthetic sulfonate obtained by sulfonating and neutralizing heavy alkylbenzene. These may be used alone or in combination of two. Examples of the metal species used in the sulfonic acid metal salt include alkali metals such as lithium, sodium, and potassium, alkaline earth metals such as magnesium, calcium, and barium, and zinc. Considering further enhancing the rust prevention property, alkaline earth metals such as magnesium, calcium, and barium are preferable, calcium and barium are more preferable, and calcium is even more preferable. The total base number of the sulfonic acid metal salt is not particularly limited, and neutral ones with a total base number of 0 to 50 mgKOH / g and overbased ones with a total base number of 50 mgKOH / g or more can be used. Considering further enhancing the rust prevention property, a total base number of 50 mgKOH / g or more is preferable, and a total base number of 150 mgKOH / g or more is more preferable. Considering enhancing the demolding property, the upper limit is preferably 600 mgKOH / g or less of the total base number, more preferably 550 mgKOH / g of the total base number, and even more preferably 500 mgKOH / g or less of the total base number. The total base number in this embodiment is a value measured according to JIS K2501:2003, 9. Potentiometric titration method (base number: perchloric acid method). Furthermore, overbased calcium sulfonate contains fine particles of calcium carbonate. In this embodiment, the crystal structure of calcium carbonate contained in overbased calcium sulfonate is not particularly limited, but amorphous type and calcite type can be used. Calcite type sulfonate is generally commercially available in a viscous grease form at usually 15 to 60% by weight in a state dispersed in a solvent or base oil, and its production method is known. For example, it is disclosed in U.S. Patent No. 3,565,672, U.S. Patent No. 3,661,622, U.S. Patent No. 3,746,643, U.S. Patent No. 3,816,310, etc. Amorphous type sulfonate is generally commercially available in an oily form at usually 15 to 60% by weight in a state diluted with a solvent or base oil, and its production method is known. For example, it is disclosed in JP-A-57-118551, JP-B-7-376255, etc. Considering enhancing the paintability and rust prevention property, a grease-like overbased calcium sulfonate having a calcite type calcium carbonate crystal structure is more preferable. That is, the metal sulfonate (C) used in this embodiment is preferably an alkaline earth metal sulfonate, more preferably a calcium sulfonate, still more preferably an overbased calcium sulfonate, and particularly preferably an overbased calcium sulfonate containing calcite type calcium carbonate.

[0030] The rust preventive agent according to the present invention is characterized in that the ratio (B) / (A) of (B) to (A) in the total weight of the composition and the ratio (C) / (A) of (C) to (A) in the total weight of the composition are 0.08 to 2.5 and 0.4 to 5.5, respectively, where (A) is the lubricating base oil, (B) is the rust preventive additive, and (C) is the metal sulfonate. Thereby, it is possible to form a coating film that exhibits sufficient rust prevention performance, has excellent transparency, and also has excellent film release property.

[0031] In addition, the rust preventive agent according to the present invention comprises a lubricating base oil (A), a rust preventive additive (B), and a metal sulfonate (C). Preferably, the ratio (B) / (A) of (B) to (A) in the total weight of the composition is 0.09 to 2.5, and the ratio (C) / (A) of (C) to (A) in the total weight of the composition is 0.5 to 4.0. Thereby, it becomes possible to form a coating film that exhibits more sufficient rust preventive performance, has excellent transparency, and also has excellent film release properties.

[0032] Furthermore, the rust preventive agent according to the present invention preferably comprises a lubricating base oil (A), a rust preventive additive (B), and a metal sulfonate (C), wherein the ratio (B) / (A) of (B) to (A) in the total weight of the composition is 0.1 to 1.5, and the ratio (C) / (A) of (C) to (A) in the total weight of the composition is 1.0 to 3.0. Thereby, it becomes possible to form a coating film that exhibits even more sufficient rust preventive performance, has excellent transparency, and also has excellent film release properties.

[0033] The rust preventive composition of this embodiment may contain other components other than the above components (A) to (C). A solvent can be used to dilute the base oil (A), the rust preventive additive (B), and the metal sulfonate (C) component. Considering the reduction of viscosity to improve coatability, it may contain commonly used solvents. As the solvent, any solvent capable of dissolving the base oil (A), the rust preventive additive (B), and the metal sulfonate (C) component can be used without particular limitation. Examples include aliphatic hydrocarbon solvents such as normal paraffin-based, isoparaffin-based, and naphthene-based solvents, and aromatic hydrocarbon solvents such as alkylbenzene and alkylnaphthalene. Considering the reduction of odor and skin irritation, aliphatic hydrocarbons such as normal paraffin-based, isoparaffin-based, and naphthene-based solvents are preferred, and considering storage stability, aliphatic hydrocarbon solvents such as naphthene-based solvents with high solubility are more preferred.

[0034] In addition, a thickener can be used for the purpose of imparting a viscosity suitable for sag resistance to the rust preventive composition. Examples of the thickener include hydrogenated castor oil wax-based, polyethylene oxide-based, amide wax-based, organically modified smectite-based clay minerals, organically modified bentonite-based clay minerals, cellulose nanofiber-based, fumed silica-based, and the like. Considering the improvement of transparency, thickeners such as amide wax-based, organically modified smectite-based clay minerals, organically modified bentonite-based clay minerals, and fumed silica-based are more preferable. In this embodiment, the use of a thickener is not an essential requirement, and an equivalent rust preventive can be provided without using a thickener. Since a higher viscosity of the rust preventive makes it less likely to sag during construction and improves the paintability, a thickener is conventionally added. Therefore, a thickener can be added to the rust preventive of this embodiment according to the needs of the customers.

[0035] In addition, a drying oil can be used for the purpose of improving the drying property of the coating film while maintaining the demolding property immediately after coating. Examples of the drying oil include, for example, safflower oil, soybean oil, rapeseed oil, bran oil, cottonseed oil, etc. with an iodine value of 90 to 120, castor oil, palm oil, etc. with an iodine value of 90 or less, and asami oil, linseed oil, polymerized linseed oil, dehydrated castor oil, perilla oil, oiticica oil, kirin oil, sardine oil, squid liver oil, synthetic drying oil, etc. with an iodine value of 120 or more. Among these, considering the increase in the drying speed, safflower oil, soybean oil, rapeseed oil, bran oil, cottonseed oil, asami oil, linseed oil, polymerized linseed oil, dehydrated castor oil, perilla oil, oiticica oil, kirin oil, sardine oil, squid liver oil, synthetic drying oil, etc. with an iodine value of 90 or more are more preferable, and asami oil, linseed oil, polymerized linseed oil, dehydrated castor oil, perilla oil, oiticica oil, kirin oil, sardine oil, squid liver oil, synthetic drying oil, etc. with an iodine value of 120 or more are even more preferable. Among these, linseed oil, dehydrated castor oil, and kirin oil with good availability are particularly preferable.

[0036] In addition, waxes can also be used within a range that does not affect the effects of the invention for the purpose of further enhancing rust prevention properties and coating film strength. Since waxes have high crystallinity and crystallize in the coating film to reduce transparency, the content is, for example, 5% by weight or less, preferably 3% by mass or less, more preferably 2% or less, and even more preferably 1% or less. As the waxes, natural waxes, synthetic waxes, etc. can be used. Examples of natural waxes include plant-based waxes such as candelilla wax, carnauba wax, rice wax, and wood rosin, animal-based waxes such as beeswax and whale wax, mineral-based waxes such as montan wax, ozokerite, and ceresin, and petroleum waxes such as paraffin wax, microcrystalline wax, and petrolatum. Examples of synthetic waxes include hydrocarbon-based waxes such as polyethylene wax and Fischer-Tropsch wax, and montan wax derivatives such as acid wax, ester wax, and partially saponified ester wax produced by solvent extraction, oxidation, esterification, saponification, etc. of montan wax.

[0037] As described above, in this embodiment, a solvent or the like can be used, but the total weight percentage of the base oil (A), the rust prevention additive (B), and the metal sulfonate (C) may be 100% from the viewpoint of VOC reduction. However, when the total weight percentage of (A + B + C) is high, the viscosity of the rust prevention composition is high, and the paintability and the leveling property of the coating film decrease. Therefore, the total weight percentage of the base oil (A), the rust prevention additive (B), and the metal sulfonate (C) is more preferably 10 to 60%.

[0038] The rust preventive of this embodiment is prepared by adding an aliphatic hydrocarbon solvent as a solvent for diluting each raw material of the base oil (A) and the rust prevention additive (B) according to the formulations described in Tables 1 to 4, heating at 80 ° C for 5 to 10 minutes to dissolve, then cooling to 30 ° C or lower, adding the metal sulfonate (C) and an amide wax paste as a thickener for imparting viscosity, and stirring for 5 to 10 minutes using a disperser.

Table 1

Table 2

Table 3

Table 4

Table 5

Table 6

Table 7

[0039] The details of each component in the above Tables 1 to 7 are as follows. Solvent: T-SOL 3040 manufactured by ENEOS, an aliphatic hydrocarbon-based solvent with a flash point of 45°C and an aromatic content of 18 vol% Base oil 1: ISO VG460 paraffin-based base oil with a kinematic viscosity at 40°C of 498 mm 2 / s and a flash point of 326°C Base oil 2: ISO VG46 paraffin-based base oil with a kinematic viscosity at 40°C of 47.7 mm 2 / s and a flash point of 256°C Oxidized petrolatum: Oxidized petrolatum obtained by oxidizing petrolatum, having a pour point of 40°C, an acid value of 33 mgKOH / g, and a saponification value of 100 mgKOH / g Calcium salt of oxidized petrolatum: Calcium salt of oxidized petrolatum using the above oxidized petrolatum as a raw material, having a softening point of 50°C and an acid value of 4 mgKOH / g Oxidized wax: Oxidized wax obtained by oxidizing paraffin wax, having a freezing point of 45°C, an acid value of 73 mgKOH / g, and a saponification value of 180 mgKOH / g Calcium salt of oxidized wax: Calcium salt of oxidized wax using the above oxidized wax as a raw material, having a softening point of 110°C and an acid value of 4 mgKOH / g Oxidized wax ester: An oxidized wax C1-18 alkyl ester with a pour point of 35°C, an acid value of 12 mg KOH / g, and a saponification value of 165 mg KOH / g, esterified using the above oxidized wax as a raw material. Sorbitan monostearate: A commercially available reagent Sorbitan monooleate: A commercially available reagent Sorbitan sesquioleate: A commercially available reagent Pentaerythritol tetraoleate: A kinematic viscosity at 40°C of 65 mm 2 / s and an acid value of 0.5 mg KOH / g Lanolin fatty acid pentaerythritol ester: A melting point of 46°C, an acid value of 5 mg KOH / g, and a saponification value of 170 mg KOH / g Calcium lanolin fatty acid: Solvent-based, an ash content of 2.5%, and a solid content of 50% (the addition amount in the above table is in terms of solid content conversion) Paraffin wax: Paraffin wax with a melting point of 69°C, 155 Microcrystalline wax: Microcrystalline wax with a melting point of 84°C Overbased calcium sulfonate (calcite type): Solvent-based grease-like, a total base number of 225 mg KOH / g, a viscosity of 70 Pa·s (Brookfield viscometer, spindle 6, 10 rpm), and a solid content of 50 w% (the addition amount in the above table is in terms of solid content conversion) Overbased calcium sulfonate (amorphous type): Mineral oil-based oily, a total base number of 495 mg KOH / g, a kinematic viscosity at 100°C of 200 mm 2 / s and a solid content of 60 w% (the addition amount in the above table is in terms of solid content conversion) Neutral calcium sulfonate: A total base number of 30 mg KOH / g, a kinematic viscosity at 100°C of 55 mm 2 / s and a solid content of 45 w% (the addition amount in the above table is in terms of solid content conversion) Overbased magnesium sulfonate: A total base number of 395 mg KOH / g, a kinematic viscosity at 100°C of 75 mm 2 / s and a solid content of 40 w% (the addition amount in the above table is in terms of solid content conversion) Neutral barium sulfonate: A total base number of 3 mg KOH / g, a kinematic viscosity at 100°C of 40 mm 2 / s and a solid content of 55% (the addition amount in the above table is in terms of solid content conversion) Rosin: Commercially available reagent, chemical rosin, concentration 90% or higher Linseed oil: Commercially available reagent Amide wax: Paste form, solid content 20% (the addition amounts in the above table are in terms of solid content)

[0040] Using the rust preventive agent obtained in this embodiment, a rust prevention performance test was conducted. For a cold-rolled steel sheet (JIS G 3141 SPCC-SD) of 150 mm × 70 mm × 0.8 mm, which was degreased with mineral spirit and dried, a sample was applied with a bar coater No. 44 to a film thickness of 100 μm, and dried for 24 hours to prepare a test piece. This test piece was subjected to a neutral salt spray test in accordance with JIS K5600:1999 7-1. Resistance to neutral salt spray. The occurrence of rust on the test piece was confirmed at intervals of 24 hours, 72 hours, 168 hours, 312 hours, 504 hours, 720 hours, and 1008 hours, and the rust occurrence time was evaluated. The results are shown in the property items of Tables 1 to 4. In this embodiment, those in which rust did not occur after 504 hours or more were regarded as having excellent rust prevention performance (B evaluation), and those in which rust did not occur after 720 hours or more were regarded as having even more excellent rust prevention performance (A evaluation).

[0041] Next, using the rust preventive agent obtained in this embodiment, a transparency test was conducted. A sample was applied to a BYK anti-hiding test paper Vicot chart high brightness 2A clear coat with a bar coater No. 68 of Daiichi Rika Co., Ltd. to a film thickness of 150 μm, and dried for 24 hours to prepare a test piece. A color analyzer TES3250 was used as the color difference meter. The black part where the sample of the anti-hiding test paper was not applied was set as the target color, and the color difference between the black part where the sample of the test piece was applied and the target color was measured. The measured value was output as the lightness difference ΔL * and evaluated as follows: ΔL * of 3.5 or less: A, more than 3.5 and 9 or less: B, more than 9 and 15 or less: C, more than 15: D. The results are shown in the property items of Tables 1 to 4.

[0042] Next, a demolding test was conducted using the rust preventive agent obtained in this embodiment. A sample was applied to a galvanized steel sheet (JIS G 3303) of 150 mm × 70 mm × 0.3 mm with a film thickness of 100 μm using a Daiichi Rika Co., Ltd. bar coater No. 44 and dried for 24 hours to prepare a test piece. A commercially available fine-pored sponge for car washing cut into 100 mm × 100 mm × 50 mm was used as a demolding jig. As the demolding detergent, a commercially available concentrated neutral detergent for car washing was diluted 20 times and used. The test piece was rubbed 10 times back and forth in the longitudinal direction using the demolding jig impregnated with the diluted detergent. The measurement surface for demolding was set to 50 mm × 50 mm at the center of the test piece. The measurement surface was divided into 100 squares of 5 mm on each side of a checkerboard pattern, and the number of squares where the coating film was removed was counted with the naked eye to measure the removal rate of the coating film. The demolding property was evaluated as follows: removal rate of 80% or more: A, 20% or more and less than 80%: B, less than 20%: C. The results are shown in the property items of Tables 1 to 4.

[0043] From the test results of the rust preventive agent used in this embodiment, it was found that excellent rust preventive performance can be exhibited when the weight ratio of the base oil (A) to the rust preventive additive (B) is (B) / (A) = 0.08 to 2.5, and the weight ratio of the base oil (A) to the metal sulfonate (C) is (C) / (A) = 0.4 to 5.5. Also, it was found that in addition to excellent rust preventive performance, transparency is improved when the weight ratio of the base oil (A) to the rust preventive additive (B) is (B) / (A) = 0.09 to 2.5, and the weight ratio of the base oil (A) to the metal sulfonate (C) is (C) / (A) = 0.5 to 4.0. Furthermore, it was found that when the weight ratio of the base oil (A) to the rust preventive additive (B) is (B) / (A) = 0.1 to 1.5, and the weight ratio of the base oil (A) to the metal sulfonate (C) is (C) / (A) = 1 to 3, it has excellent rust preventive performance, transparency, and demolding property.

Claims

1. A rust preventive composition containing base oil (A), rust preventive additive (B), and metal sulfonate (C), wherein the weight ratio of the base oil (A) to the rust preventive additive (B) is (B) / (A) = 0.08 to 2.5, and the weight ratio of the base oil (A) to the metal sulfonate (C) is (C) / (A) = 0.4 to 5.

5. The rust preventive composition is characterized by this.

2. The rust preventive composition according to Claim 1, wherein the rust preventive additive (B) is a rust preventive additive (B) containing at least one of the structures of Chemical Formulas 1 and 2 below. Chemical Formula 1: 【Chemical 1】 Chemical Formula 2: [Chemical Formula 2] R1: Hydrocarbon group R1 may be substituted and may be a saturated hydrocarbon, unsaturated hydrocarbon, alicyclic hydrocarbon, or aromatic ring hydrocarbon. R2 is either hydrogen, a hydrocarbon group, an alkali metal, or an alkaline earth metal, and the hydrocarbon group may be substituted. R3, R4, R5: Hydrogen or hydrocarbon group R1 may be substituted and may be a saturated hydrocarbon, unsaturated hydrocarbon, alicyclic hydrocarbon, or aromatic ring hydrocarbon. R1, R3, R4, and R5 may be the same or different groups.

3. The rust preventive composition according to Claim 1, wherein the rust preventive additive (B) component is one or more rust preventive additives (B) selected from the group consisting of fatty acids, fatty acid metal salts, fatty acid esters, fatty acid amine salts, oxidized waxes, oxidized wax metal salts, oxidized wax esters, oxidized wax amine salts, oxidized petrolatum, oxidized petrolatum metal salts, oxidized petrolatum esters, and oxidized petrolatum amine salts.

4. The rust preventive composition according to any one of Claims 1 to 3, wherein the metal sulfonate (C) is an alkaline earth metal sulfonate.

5. The rust preventive composition according to Claim 1, wherein the weight ratio of the base oil (A) to the rust preventive additive (B) is (B) / (A) = 0.09 to 2.5, and the weight ratio of the base oil (A) to the metal sulfonate (C) is (C) / (A) = 0.5 to 4.

0.

6. The rust preventive composition according to Claim 1, wherein the weight ratio of the base oil (A) to the rust preventive additive (B) is (B) / (A) = 0.1 to 1.5, and the weight ratio of the base oil (A) to the metal sulfonate (C) is (C) / (A) = 1 to 3.

Images