FIELD OF THE INVENTION

The present invention relates to a cleaning composition for metal substrates pretreatment and its preparation method thereof. More specifically, the present invention relates to a cleaning composition for cleaning grease and sweat from metal substrates and its preparation method thereof.

BACKGROUND OF THE INVENTION

Metal substrates such as pipes, plates, etc. are coated by protective films to eliminate rusting and therefore increase their service life. In order to get excellent coating films and make the binding between metal substrates and coating films durable, metal substrates have to be pretreated before coating, for example, including steps of sanding the metal substrates and cleaning the residual grease and inorganic salts from metal substrates, said grease and salts are included in fingerprints and sweat respectively.

If the coating film is applied onto metal substrates having residual grease and salts, water from humid environment tends to penetrate the coating film and bring corrosions to metal surfaces together with sodium chloride and oxygen. The mechanism of corrosion is: the coating film as a cathode, the metal substrate as an anode, and the mixture of water and sodium chloride as an electrolyte, form a cell. The corrosion will make the coating film bubble and lose its protective function such as water resistance.

Various cleaning compositions have been developed for metal substrates pretreatment and those cleaning compositions mainly include two types i.e. solvent-borne and water-borne cleaning compositions both of which have problems. When solvent-borne cleaning compositions are used, inorganic salts cannot be removed completely, while when water-borne cleaning compositions are used, water itself will cause corrosion.

US5,080,831A disclosed an aqueous cleaning composition comprising: (a) at least one sparingly water soluble organic solvent; (b) a solubilizing additive consisting of a surfactant and a coupler; and (c) water. US5,080,831A conducted a degreasing test and the results showed that the aqueous cleaning composition can remove grease/oil from walls, metal surfaces, etc. with scrubbing. However, US5,080,831A did not provide anti-corrosion effects on metal substrates, nor water resistance of the coating film over metal substrates.

CN110983355A disclosed a degreasing and anti-rusting agent for iron workpieces, comprising alkaline auxiliary agents, chelating agents, surfactants, rust inhibitors and solubilizing agents, wherein the alkaline auxiliary agents include at least one selected from a group consisting of sodium carbonate, potassium carbonate, sodium hydroxide, potassium hydroxide and sodium metasilicate pentahydrate. In this patent, it is required to make the iron workpieces soaked in the degreasing and anti-rusting agent with heating to remove grease from the surface of the iron workpieces. Moreover, the degreasing and anti-rusting agent comprises inorganic substances such as alkaline auxiliary agents that will remain on the metal substrates after degreasing, which will adversely affect the subsequent coating film.

Therefore, it is still required to provide a cleaning composition which can effectively remove grease and inorganic salts from metal substrates and therefore avoid corrosions of metal substrates.

SUMMARY OF THE INVENTION

In one aspect, this invention provides a cleaning composition comprising a) from 40% to 80% by weight of one or more alcohol solvents; b) from 5% to 20% by weight of one or more ester solvents; c) from 5% to 30% by weight of one or more ether solvents; d) from 0.5% to 5% by weight of one or more corrosion inhibitors; and e) from 5% to 30% by weight of water, wherein the weight percentage of each component is based on the total weight of the cleaning composition.

In another aspect, the present invention provides a method for preparing the cleaning composition, comprising steps of:

(1) mixing alcohol solvents, ester solvents and ether solvents with stirring uniformly,

(2) further adding corrosion inhibitors with stirring uniformly,

(3) further adding water with stirring uniformly, and

(4) filtering the obtained mixture.

The cleaning composition of the present invention can effectively remove grease and inorganic salts from metal substrates and therefore can avoid corrosions of the metal substrate. Moreover, it is simple to prepare the clean composition and convenient to apply it onto metal surfaces.

After pretreatment by the invented cleaning composition, the coated films have better water resistance compared with the prior art.

DETAILED DESCRIPTION OF THE INVENTION

The present invention will be described in detail hereinafter. It is to be understood that the present invention can be embodied in many different ways and shall not be construed as limited to the embodiments set forth herein.

The singular forms “a”, “an” and “the” include plural referents unless the context clearly dictates otherwise. The terms “comprise”, “comprising”, etc. are used interchangeably with “include”, “including”, etc. and are to be interpreted in a non-limiting, open manner. That is, e.g., further components or elements can be present. The expressions “consists of” or “consists essentially of” or cognates can be embraced within “comprises” or cognates.

Alcohol Solvents

According to the present invention, solvents comprising a hydroxyl group in the structure can be used as alcohol solvents.

The alcohol solvents can include linear, branched or cyclic, substituted or unsubstituted aliphatic or aromatic alcohols, including monohydric alcohols, dihydric alcohols, trihydric alcohols and tetrahydric alcohols, preferably C1-C20 aliphatic alcohols or aromatic alcohols.

In some embodiments, the aliphatic monohydric alcohols include linear or branched, substituted or unsubstituted C1-C20, preferably C2-C10 alkanols and substituted or unsubstituted C5-C20, preferably C5-C10 cycloalkanols, examples of which include, but are not limited to, methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, tert-butanol, n-pentanol, isopentanol, cyclopentanol, n-hexanol, isohexanol, cyclohexanol, n-heptanol, isoheptanol, cycloheptanol, n-octanol, isooctyl alcohol, 2-ethylhexanol, cyclooctanol, n-nonanol, isononanol, n-decanol, isodecanol, 2-propylheptanol, undecanol, dodecanol, tridecanol or mixtures thereof, preferably ethanol, n-propanol, isopropanol, n-butanol, isobutanol, n-pentanol , isopentanol, n- hexanol, isohexanol, heptanol, isoheptanol, n-octanol, isooctyl alcohol, 2-ethylhexanol or mixtures thereof, more preferably ethanol, n-propanol, isopropanol, n-butanol, isobutanol or a mixture thereof, still more preferably ethanol, n-propanol, isopropanol or a mixture thereof, and even more preferably ethanol, isopropanol or a mixture thereof.

In some embodiments, the aliphatic dihydric alcohols include linear or branched, substituted or unsubstituted C2-C20, preferably C2-C10 alkanediols and substituted or unsubstituted C5-C20, preferably C5-C10 cycloalkanes diols, examples of which include, but are not limited to, ethylene glycol, 1 ,2-propanediol, 1 ,3-propanediol, 1 ,4-butanediol, 2,3-butanediol, ethyl glycol, 2- (hydroxymethyl) propanol, 1 ,5-pentanediol, 1 ,3-pentanediol, 2,4-pentanediol, cyclopentane- 1 ,2- diol, propyl glycol, 2-(hydroxyethyl)propanol, 2-(hydroxymethyl)butanol, 1 ,6-hexanediol, 2,5- hexanediol, butyl glycol, 2-methyl-2,4-pentanediol (isohexanediol), 1 ,2-cyclohexanediol, 1 ,3- cyclohexanediol, 1 ,4-cyclohexanediol, 1 ,7-heptanediol, 2,6-heptanediol, 3-methyl-2,4- hexanediol, 1 ,2-cycloheptanediol, 1 ,8-octanediol, 2,7-octanediol, 1 ,9-nonanediol, 1 ,10- decanediol, 4-propyl-5-ethyl-1 ,2-cycloheptanediol, 2-methyl-4,6-decanediol, 1 ,2-dodecanediol or mixtures thereof.

In some embodiments, the aliphatic trihydric alcohols include linear or branched, substituted or unsubstituted C3-C20, preferably C3-C10 alkanetriols and C5-C20, preferably C5-C10 cycloalkanetriols, examples of which include, but are not limited to, propanetriol (glycerol), 1 ,2,4-butanetriol, 1 ,2,3-pentanetriol, 2,3,4-pentanetriol, 1 ,2,3-hexanetriol , 1 ,2,5-hexanetriol, 1 ,2,3-cyclohexanetriol, 1 ,2,4-cyclohexanetriol, 1 ,2,3-heptanetriol, 1 ,6,7-heptanetriol, 2,3,6- heptanetriol, 1 ,2,3-cycloheptanetriol, 1 ,2,6-cycloheptanetriol, 1 ,2,3-octanetriol, 2,3,4-octanetriol, 1 ,2,8-octanetriol, 2,3,7-octanetriol, 1 ,2,3-nonanetriol, 2,5,10-dodecanetriol, 2,4,6-trimethyl- 1 ,8,12-dodecanetriol, 8-heptyl-1 ,2,3-undecanetriol or mixtures thereof.

In some embodiments, the aliphatic tetrahydric alcohols include pentaerythritol.

In some embodiments, the aromatic alcohols include C5-C12 aralkyl alcohols, examples of which include, but are not limited to, benzyl alcohol, 1-phenylethanol, 2-phenylethanol, phenylpropanol, pyridin-1-yl methanol, pyridin-3-yl methanol, 1-pyridin-3-yl ethanol, pyridyl butanol, pyrimidin-1-yl methanol, pyrimidin-1-yl ethanol, 2-pyrimidin-3-yl propanol, furan-2-yl methanol, 2-furan-2-yl ethanol, 3-furan-3-yl propanol, 4-furan-2-yl butanol, or a mixture thereof.

The alcohol solvents can also include alcohols comprising other groups such as ketone groups in the structure, such as diacetone alcohol.

In a preferred embodiment, the alcohol solvents have a boiling point of below 160°C, preferably below 120°C.

In a preferred embodiment, the alcohol solvent is a mixture of ethanol and isopropanol. In this mixture, the weight ratio of ethanol to isopropanol is in the range from 1 :10 to 10:1 , preferably from 1 :8 to 8: 1 , more preferably from 1 :5 to 5: 1 , and in some embodiments, from 1 :4 to 4: 1 , from 1 :3 to 3: 1 , from 1 :2 to 2: 1 , or about 1 :1.

The alcohol solvents are used in an amount of from 40% to 80%, preferably from 50% to 70%, more preferably from 55% to 65% by weight, based on the total weight of the cleaning composition.

Ester Solvents

According to the present invention, solvents comprising an ester group in the structure can be used as ester solvents.

The ester solvents include C2-C12 alkane monocarboxylic acid C1-C12 alkyl ester, hydroxylated C2-C12 alkane monocarboxylic acid C1-C12 alkyl ester, C2-C12 alkane dicarboxylic acid di-Ci -C12 alkyl ester, C1-C12 alkane monocarboxylic acid C3-C12 alkoxyalkyl ester, C3-C12 alkoxy alkane monocarboxylic acid C1-C12 alkyl ester, tri-Ci-C4 alkyl phosphates, C5-C12 cycloalkane monocarboxylic acid C1-C12 alkyl ester, C5-C12 cycloalkane dicarboxylic acid di-Ci-Ci2 alkyl ester, carbonate, aromatic (for example, phenyl) carboxylic acid ester or a mixture thereof.

The C2-C12 alkane monocarboxylic acid C1-C12 alkyl esters refer to monocarboxylic acid esters formed by an alkane monocarboxylic acid having 2 to 12 carbon atoms and an alkyl monohydric alcohol having 1 to 12 carbon atoms, examples of which include, but are not limited to, methyl acetate, ethyl acetate, isopropyl acetate, n-propyl acetate, isobutyl acetate, tert-butyl acetate, n- pentyl acetate, cyclopentyl acetate, n-hexyl acetate, 3-methylcyclopentyl acetate, cyclohexyl acetate, n-heptyl acetate, 3-methylcyclohexyl acetate, 2-ethylhexyl acetate, n-nonyl acetate, isobornyl acetate, ethyl propionate, n-propyl propionate, isopropyl propionate, n-butyl propionate, tert-butyl propionate, n-pentyl propionate, n-hexyl propionate, cyclohexyl propionate, n-propyl isopropionate, cyclopropyl propionate, cyclopropyl isopropionate, isopropyl isopropionate, n-butyl isopropionate, tert-butyl isopropionate, n-pentyl isopropionate, propylheptyl isopropionate, ethyl butyrate, n-propyl butyrate, isopropyl butyrate, n-butyl butyrate, tert-butyl butyrate, n-decyl butyrate, ethyl tert-butyrate, n-propyl tert- butyrate, isopropyl tertbutyrate, n-butyl tert-butyrate, tert-butyl tert-butyrate, n-pentyl butyrate, methyl valerate, ethyl valerate, propyl valerate, isopropyl valerate, n-butyl valerate, methyl caproate, ethyl caproate, isopropyl caproate, tert-butyl caproate, methyl heptanoate, ethyl heptanoate, methyl octanoate, n-pentyl 4-ethyl octanoate, ethyl nonanoate or mixtures thereof.

The hydroxylated C2-C12 alkane monocarboxylic acid C1-C12 alkyl esters refer to monocarboxylic acid ester formed by an alkane monocarboxylic acid having 2 to 12 carbon atoms and an alkyl group monohydric alcohol having 1 to 12 carbon atoms, wherein the alkyl group derived from carboxylic acid or the alkyl group derived from alcohol is substituted by at least one hydroxyl group, examples of which include, but are not limited to, 3-hydroxypropyl acetate, 3- hydroxybutyl acetate, 5-hydroxypentyl acetate, n-propyl glycolate, isopropyl glycolate, n-butyl glycolate, tert-butyl glycolate, n-pentyl glycolate, n-hexyl glycolate, 2-methylpentyl glycolate, cyclohexyl glycolate, 3-methylcyclopentyl glycolate, n-heptyl glycolate, cyclohexyl ethyl glycolate, 3-isopropylcyclopentyl glycolate, 2-hydroxyethyl propionate, 3-hydroxypropyl propionate, 3-hydroxypentyl propionate, 3-hydroxycyclopentyl propionate, 2-hydroxymethylbutyl propionate, methyl lactate, ethyl lactate, n-propyl lactate, isopropyl lactate, 2-methylpropyl lactate, 2-ethylpropyl lactate, n-butyl lactate, isobutyl lactate, cyclopentyl lactate , 2-ethylpentyl lactate, 2-ethylhexyl lactate, decyl lactate, 2-hydroxyethyl butyrate, 3-hydroxypropyl butyrate, 2- hydroxymethylpropyl butyrate, methyl 4-hydroxybutyrate, ethyl 4-hydroxybutyrate, n-propyl 4- hydroxybutyrate, isopropyl 3-hydroxybutyrate, isopropyl 4-hydroxybutyrate, n-propyl 4- hydroxybutyrate, isobutyl 3-hydroxybutyrate, n-pentyl 4-hydroxybutyrate, 2-ethylhexyl 3- hydroxybutyrate, 2-hydroxyethyl valerate, 3-hydroxypropyl valerate, ethyl 3-propyl-4- hydroxyhexanoate, n-propyl 4-hydroxyoctanoate, isopropylhexyl 4-hydroxyoctanoate, tert-butyl 3-hydroxydecanoate, or mixtures thereof.

The C2-C12 alkane dicarboxylic acid di-Ci -C12 alkyl esters refer to dicarboxylic acid esters formed by an alkane dicarboxylic acid having 2 to 12 carbon atoms and two independently selected alkyl monohydric alcohols having 1 to 12 carbon atoms, examples of which include, but are not limited to, ethyl methyl oxalate, diethyl oxalate, ethyl propyl oxalate, ethyl isopropyl oxalate, dipropyl oxalate, propyl isopropyl oxalate, ethyl butyl oxalate, methyl pentyl oxalate, propyl butyl oxalate, butyl hexyl oxalate, dipentyl oxalate, dimethyl malonate, methyl ethyl malonate, diethyl malonate, propyl ethyl malonate, isopropyl ethyl malonate, methyl propyl malonate, methyl isopropyl malonate, dipropyl malonate, di-isobutyl malonate, dihexyl malonate, ethyl pentyl malonate, dimethyl succinate, ethyl methyl succinate, diethyl succinate, methyl propyl succinate, methyl isopropyl succinate, ethyl propyl succinate, dipropyl succinate, diisopropyl succinate, di-isobutyl succinate, dipentyl succinate, dimethyl glutarate, ethyl methyl glutarate, diethyl glutarate, di-isopropyl glutarate, di-isobutyl glutarate, ethyl pentyl glutarate, dicyclopentyl glutarate, dimethyl adipate, ethyl methyl adipate, di-isobutyl adipate, ethyl propyl adipate, dimethyl pimelate, diethyl pimelate, di-isobutyl pimelate, or mixtures thereof.

The C1-C12 alkane monocarboxylic acid C3-C12 alkoxyalkyl esters refer to monocarboxylic acid esters formed by an alkane monocarboxylic acid having 1 to 12 carbon atoms and an alkoxyalkyl monohydric alcohol having 3 to 12 carbon atoms, examples of which include, but are not limited to, isopropoxymethyl formate, isopropoxyethyl formate, isopropoxy tert-butyl formate, methoxypropyl acetate, ethoxymethyl acetate, ethoxypropyl acetate, propoxypropyl acetate, isopropoxymethyl acetate, isopropoxypropyl acetate, ethylene glycol ethyl ether formate, ethylene glycol butyl ether formate, ethylene glycol 2-methylbutyl ether formate, ethylene glycol amyl ether formate, ethylene glycol methyl ether acetate, ethylene glycol ethyl ether acetate, ethylene glycol propyl ether acetate, ethylene glycol butyl ether acetate, ethylene glycol tert-butyl ether acetate, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol propyl ether acetate, propylene glycol isopropyl ether acetate, propylene glycol pentyl ether acetate, propylene glycol butyl ether valerate, ethylene glycol methyl ether butyrate, ethylene glycol ethyl ether butyrate, propylene glycol methyl ether butyrate, propylene glycol methyl ether 2-methyl propionate, propoxypropyl propionate, methoxypropyl 2-methyl propionate, methoxypropyl butyrate, isopropoxymethyl butyrate, butoxyethyl butyrate, pentoxypropyl butyrate, propoxymethyl tert-butyrate, ethylene glycol methyl ether 3-methyl butyrate, ethylene glycol methyl ether valerate or mixtures thereof.

The C3-C12 alkoxy alkane monocarboxylic acid C1-C12 alkyl esters refer to monocarboxylic acid esters formed by an alkoxy alkane monocarboxylic acid having 3 to 12 carbon atoms and an alkyl monohydric alcohol having 1 to 12 carbon atoms, preferably C3-C6 alkoxy alkane monocarboxylic acid Ci-Ce alkyl ester, examples of which include, but are not limited to, ethyl 3- methoxypropionate, ethyl 3-ethoxypropionate or a mixture thereof. In a preferred embodiment, the ester solvent is ethyl 3-ethoxypropionate.

The tri-Ci -C4 alkyl phosphates include, but are not limited to, trimethyl phosphate, triethyl phosphate, tri-n-propyl phosphate, tri-isopropyl phosphate, tri-n-butyl phosphate, triisobutyl phosphate, methyl diethyl phosphate, dimethyl ethyl phosphate, methyl di-n-propyl phosphate, methyl ethyl n-propyl phosphate, ethyl 2-methylpropyl methyl phosphate, diethyl n-propyl phosphate, dimethyl isobutyl phosphate, diethyl n-butyl phosphate, n-propyl isobutyl n-butyl phosphate and dimethyl tert-butyl phosphate.

The C5-C12 cycloalkane monocarboxylic acid C1-C12 alkyl esters refer to monocarboxylic acid esters formed by a cycloalkane monocarboxylic acid having 5 to 12 carbon atoms and an alkyl monohydric alcohol having 1 to 12 carbon atoms, examples of which include, but are not limited to, hexyl cyclopentanecarboxylate, pentyl cyclohexanecarboxylate, 3-isopropylhexyl cyclohexanecarboxylate, or mixtures thereof.

The C5-C12 cycloalkane dicarboxylic acid di-Ci -Ci 2 alkyl esters refer to dicarboxylic acid esters formed by a cycloalkane dicarboxylic acid having 5 to 12 carbon atoms and two independently selected alkyl monohydric alcohols having 1 to 12 carbon atoms, examples of which include, but are not limited to, dibutyl 1 ,2-cyclopentane dicarboxylate, ethyl butyl 1 ,3-cyclopentane dicarboxylate, didecyl 1 ,2-cyclohexanedicarboxylate, methyl octyl 1 ,4-cyclohexanedicarboxylate, di-isononyl cyclohexanedicarboxylate or mixtures thereof.

In some embodiments, carbonates include, but are not limited to, diethyl carbonate (DEC), ethyl methyl carbonate (EMC), methyl propyl carbonate, dibutyl carbonate, or mixtures thereof.

In some embodiments, aromatic (e.g., phenyl) carboxylic acid esters refer to carboxylic acid esters comprising aromatic groups, examples of which include, but are not limited to, benzyl acetate, methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, benzyl lactate, 2- phenoxyethyl propionate or mixtures thereof.

In a preferred embodiment, the ester solvents have a boiling point of below 200°C, preferably below 160°C.

According to the present invention, the amount of ester solvent used is from 5% to 20%, preferably from 8% to 15%, more preferably from 10% to 12% by weight, based on the total weight of the cleaning composition.

Ether Solvents

According to the present invention, solvents comprising ether bonds in the structure can be used as ether solvents.

In some embodiments, ether solvents include ethers having the general formula R ¹ -O-R ² , wherein R ¹ and R ² are each independently a hydrocarbyl group having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, examples of which include, but are not limited to, dimethyl ether, ethyl methyl ether, diethyl ether, methyl propyl ether, di-isopropyl ether, di-n-butyl ether, methyl tert-butyl ether (MTBE) or mixtures thereof.

In some embodiments, the ether solvents include ethers having the general formula R ³ -O-(R ⁴ - O) _n -R ⁵ , wherein R ³ is H or a hydrocarbyl group having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, R ⁴ and R ⁵ are each independently a hydrocarbyl group having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, and n is an integer of 1-6, examples of which include, but are not limited to, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether (propylene glycol butyl ether), ethylene glycol dimethyl ether, ethylene glycol diethyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol dibutyl ether, diethylene glycol monomethyl ether, diethylene glycol dimethyl ether, diethylene glycol monoethyl ether, diethylene glycol diethyl ether, diethylene glycol monopropyl ether, diethylene glycol dipropyl ether, diethylene glycol monobutyl ether, diethylene glycol dibutyl ether, triethylene glycol monomethyl ether, triethylene glycol dimethyl ether, triethylene glycol monoethyl ether, triethylene glycol diethyl ether, tetraethylene glycol monomethyl ether, tetraethylene glycol dimethyl ether or mixtures thereof. In a preferred embodiment, the ether solvent is ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether (propylene glycol butyl ether) or a mixture thereof.

In some embodiments, the ether solvents include cyclic ethers, examples of which include, but are not limited to, tetrahydrofuran, 2-methyltetrahydrofuran, 1 ,3-oxocyclopentane, or mixtures.

In a preferred embodiment, the ether solvents have a boiling point of below 200°C, preferably below 160°C.

According to the present invention, the amount of ether solvent is from 5% to 30%, preferably from 10% to 25%, more preferably from 15% to 23% by weight, based on the total weight of the cleaning composition.

Solvents comprising two or more moieties of a hydroxyl group, an ester group and an ether bond in the structure can act as two or more solvents among alcohol solvents, ester solvents and ether solvents. For example, a solvent comprising a hydroxyl group and an ether bond in the structure can act as both ether solvent and alcohol solvent.

Corrosion Inhibitors

According to the present invention, corrosion inhibitors can also be referred to as flash rust inhibitors or rust inhibitors.

In some embodiments, the corrosion inhibitor is a polymer-based corrosion inhibitor, especially a polyacrylic acid corrosion inhibitor.

In one embodiment, the corrosion inhibitors include organozinc chelates, such as NALZIN® FA 179, NALZIN® FA 379, and NALZIN® FA 579 available from ELEMENTIS. The corrosion inhibitors comprise no nitrite and is a chelating zinc compound soluble in a mixture of various solvents, which shows a strong affinity for iron-containing substrates to prevent flash corrosion. Although the corrosion inhibitor is water-soluble, it can be transformed into a non-dispersible or insoluble zinc compound during drying, such that the water sensitivity is reduced, forming an anti-corrosion passivation layer after drying, thereby improving water resistance of subsequent paint films on metal substrates.

In one embodiment, the corrosion inhibitors include zinc-free rust inhibitor, such as HALOX® FLASH-X® 150, HALOX® SW-111, etc., available from HALOX.

In one embodiment, the corrosion inhibitors include alkylamine-containing corrosion inhibitors, such as those raybo® series of rust inhibitors available from Raybo Chemical Company, such as raybo 60, raybo 80, raybo 90, raybo 218, especially raybo 90 and raybo 218. According to the present invention, the amount of corrosion inhibitor used is from 0.5% to 5%, preferably from 0.5% to 2%, more preferably from 0.5% to 1.5% by weight, based on the total weight of the cleaning composition.

Water

In a preferred embodiment, the water is deionized water, demineralized water or distilled water.

According to the present invention, the amount of water used is from 5% to 30%, preferably from 5% to 20%, more preferably from 8% to 15% by weight, based on the total weight of the cleaning composition.

Other Additives

According to the present invention, the cleaning composition can further comprise additives, including but not limited to anti-corrosion auxiliary agents (for example, HALOX® 550 available from HALOX), solubilizers, antioxidants, antibacterial agents, or combinations thereof.

Unless otherwise indicated, all contents or ratios mentioned in the present invention are by weight. In the context of the present invention, the sum of the weight percentage of each component in the cleaning composition is 100wt%.

Preparation Method of Cleaning Composition

The method for preparing a cleaning composition according to the present invention comprises steps of:

(1) mixing alcohol solvents, ester solvents and ether solvents with stirring uniformly,

(2) further adding corrosion inhibitors with stirring uniformly,

(3) further adding water with stirring uniformly, and

(4) filtering the obtained mixture.

In a preferred embodiment, the method for preparing a cleaning composition according to the present invention is carried out at room temperature (0-40°C).

Application

The cleaning compositions of the present invention can effectively remove grease and inorganic salts from metal substrates and therefore avoid corrosions of metal substrates and enable coating films a good water resistance.

In the present invention, metal substrates include but not limited to iron, aluminum alloy, copper substrates and other metal substrates. In some embodiments, the metal substrate is a galvanized sheet or an aluminum alloy sheet of an automobile body. In some embodiments, the iron substrates include tinplates, steel sheets, galvanized sheets and the like. Embodiment

Although the following detailed description gives specific preferred embodiments, the persons skilled in the art should understand that these embodiments are only for example and the present invention can be practiced in alternative ways.

Embodiment 1

A cleaning composition comprises: a) from 50% to 70% by weight of one or more alcohol solvents, b) from 5% to 15% by weight of one or more ester solvents, c) from 15% to 25% by weight of one or more ether solvents, d) from 0.5% to 2% by weight of one or more corrosion inhibitors, and e) from 5% to 20% by weight of water, wherein the weight percentage of each component is based on the total weight of the cleaning composition.

Embodiment 2

A cleaning composition comprises: a) from 50 to 70% by weight of one or more alcohol solvents, b) from 5 to 15% by weight of one or more ester solvents, c) from 15 to 25% by weight of one or more ether solvents, d) from 0.5 to 2% by weight of one or more corrosion inhibitors, and e) from 5 to 20% by weight of water, wherein the weight percentage of each component is based on the total weight of the cleaning composition, and the corrosion inhibitors comprise polymer-based corrosion inhibitors.

Embodiment 3

A cleaning composition comprises: a) from 50% to 70% by weight of one or more alcohol solvents, b) from 5% to 15% by weight of one or more ester solvents, c) from 15% to 25% by weight of one or more ether solvents, d) from 0.5% to 2% by weight of one or more corrosion inhibitors, and e) from 5% to 20% by weight of water, wherein the weight percentage of each component is based on the total weight of the cleaning composition, and the corrosion inhibitors comprise polyacrylic acid corrosion inhibitors.

Embodiment 4

A cleaning composition comprises: a) from 50% to 70% by weight of one or more alcohol solvents, b) from 5% to 15% by weight of one or more ester solvents, c) from 15% to 25% by weight of one or more ether solvents, d) from 0.5% to 2% by weight of one or more corrosion inhibitors, and e) from 5% to 20% by weight of water, wherein the weight percentage of each component is based on the total weight of the cleaning composition, and the corrosion inhibitors comprise organic zinc chelates. Embodiment 5

A cleaning composition comprises: a) from 50% to 70% by weight of one or more alcohol solvents, b) from 5% to 15% by weight of one or more ester solvents, c) from 15% to 25% by weight of one or more ether solvents, d) from 0.5% to 2% by weight of one or more corrosion inhibitors, and e) from 5% to 20% by weight of water, wherein the weight percentage of each component is based on the total weight of the cleaning composition, the corrosion inhibitors comprise organozinc chelates and the alcohol solvents are selected from ethanol, isopropanol or a mixture thereof.

Embodiment 6

A cleaning composition comprises: a) from 50% to 70% by weight of one or more alcohol solvents, b) from 5% to 15% by weight of one or more ester solvents, c) from 15% to 25% by weight of one or more ether solvents, d) from 0.5% to 2% by weight of one or more corrosion inhibitors, and e) from 5% to 20% by weight of water, wherein the weight percentage of each component is based on the total weight of the cleaning composition, the corrosion inhibitors comprise organic zinc chelates, the alcohol solvents are selected from ethanol, isopropanol or a mixture thereof, and the ester solvents are selected from ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate or a mixture thereof.

Embodiment 7

A cleaning composition comprises: a) from 50% to 70% by weight of one or more alcohol solvents, b) from 5% to 15% by weight of one or more ester solvents, c) from 15% to 25% by weight of one or more ether solvents, d) from 0.5% to 2% by weight of one or more corrosion inhibitors, and e) from 5% to 20% by weight of water, wherein the weight percentage of each component is based on the total weight of the cleaning composition, the corrosion inhibitors comprise organic zinc chelates, the alcohol solvents are selected from ethanol, isopropanol or a mixture thereof, the ester solvents are selected from ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate or mixtures thereof, and the ether solvents are selected from ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether or a mixture thereof.

Embodiment 8

A cleaning composition comprising a) from 40% to 80% by weight of one or more alcohol solvents; b) from 5% to 20% by weight of one or more ester solvents; c) from 5% to 30% by weight of one or more ether solvents; d) from 0.5% to 5% by weight of one or more corrosion inhibitors; and e) from 5% to 30% by weight of water, wherein the weight percentage of each component is based on the total weight of the cleaning composition.

Embodiment 9

The cleaning composition according to embodiment 8, wherein the cleaning composition comprises from 0.5% to 2%, preferably from 0.5% to 1.5% by weight of corrosion inhibitor.

Embodiment 10

The cleaning composition according to embodiment 8 or 9, wherein the corrosion inhibitors comprise polymer-based corrosion inhibitors.

Embodiment 11

The cleaning composition according to any of embodiments 8 to 10, wherein the corrosion inhibitors comprise polyacrylic acid corrosion inhibitors.

Embodiment 12

The cleaning composition according to any of embodiments 8 to 11 , wherein the corrosion inhibitors comprise organozinc chelates.

Embodiment 13

The cleaning composition according to any of embodiments 8 to 10, wherein the corrosion inhibitors comprise zinc-free rust inhibitors.

Embodiment 14

The cleaning composition according to any of embodiments 8 to 13, wherein the cleaning composition comprises from 50% to 70%, preferably from 55% to 65% by weight of alcohol solvents.

Embodiment 15

The cleaning composition according to any of embodiments 8 to 14, wherein the alcohol solvents have a boiling point of below 160°C, preferably below 120°C.

Embodiment 16

The cleaning composition according to any of embodiments 8 to 15, wherein the alcohol solvents comprise linear, branched or cyclic, substituted or unsubstituted C1-C20 aliphatic alcohols or aromatic alcohols.

Embodiment 17

The cleaning composition according to any of embodiments 8 to 16, wherein the alcohol solvents are selected from ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, tert-butanol, n-pentanol, isopentanol, cyclopentanol, n-hexanol, isohexanol, cyclohexanol, n- heptanol, isoheptanol, cycloheptanol, n-octanol, isooctyl alcohol, 2-ethylhexanol, cyclooctanol, n-nonanol, isononanol, n-decanol, isodecanol, 2-propylheptanol, undecanol, dodecanol, tridecanol or mixtures thereof, preferably ethanol, n-propanol, isopropanol or mixtures thereof. Embodiment 18

The cleaning composition according to embodiment 17, wherein the alcohol solvents are a mixture of ethanol and isopropanol in a weight ratio of from 1 :10 to 10:1 , preferably in a weight ratio of from 1 :5 to 5:1.

Embodiment 19

The cleaning composition according to any of embodiments 8 to 18, wherein the cleaning composition comprises from 5% to 15%, preferably from 8% to 12% by weight of ester solvents.

Embodiment 20

The cleaning composition according to any of embodiments 8 to 19, wherein the ester solvents have a boiling point of below 200°C, preferably below 160°C.

Embodiment 21

The cleaning composition according to any of embodiments 8 to 20, wherein the ester solvents comprise C2-C12 alkane monocarboxylic acid C1-C12 alkyl ester, hydroxylated C2-C12 alkane monocarboxylic acid C1-C12 alkyl ester, C2-C12 alkane dicarboxylic acid di-Ci -Ci 2 alkyl ester, Ci- 012 alkane monocarboxylic acid C3-C12 alkoxyalkyl ester, C3-C12 alkoxy alkane monocarboxylic acid C1-C12 alkyl ester, tri-Ci -C4 alkyl phosphates, C5-C12 cycloalkane monocarboxylic acid Ci- 012 alkyl ester, C5-C12 cycloalkane dicarboxylic acid di-Ci -C12 alkyl ester, carbonate, aromatic carboxylic acid esters or mixtures thereof.

Embodiment 22

The cleaning composition according to embodiment 21 , wherein the ester solvents are C3-C12 alkoxy alkane monocarboxylic acid C1-C12 alkyl ester, preferably selected from ethyl 3- methoxypropionate, ethyl 3-ethoxypropionate or a mixture thereof, more preferably ethyl 3- ethoxypropionate.

Embodiment 23

The cleaning composition according to any of embodiments 8 to 22, wherein the cleaning composition comprises from 15% to 25%, preferably from 17% to 23% by weight of ether solvents.

Embodiment 24

The cleaning composition according to any of embodiments 8 to 23, wherein the ether solvents have a boiling point of below 200°C, preferably below 160°C.

Embodiment 25

The cleaning composition according to any of embodiments 8 to 24, wherein the ether solvents comprise ethers having the general formula of R ¹ -O-R ² , wherein R ¹ and R ² are each independently hydrocarbyl group having 1 to 20 carbon atoms, preferably selected from dimethyl ether, ethyl methyl ether, diethyl ether, methyl propyl ether, di-isopropyl ether, di-n- butyl ether, methyl tert-butyl ether or mixtures thereof. Embodiment 26

The cleaning composition according to any of embodiments 8 to 24, wherein the ether solvents comprise ethers having the general formula of R ³ -O-(R ⁴ -O) _n -R ⁵ , wherein R ³ is H or hydrocarbyl group having 1 to 20 carbon atoms, R ⁴ and R ⁵ are each independently hydrocarbyl group having 1 to 20 carbon atoms, and n is an integer of 1 to 6, preferably selected from ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol dibutyl ether, diethylene glycol monomethyl ether, diethylene glycol dimethyl ether, diethylene glycol monoethyl ether, diethylene glycol diethyl ether, diethylene glycol monopropyl ether, diethylene glycol dipropyl ether, diethylene glycol monobutyl ether, diethylene glycol dibutyl ether, triethylene glycol monomethyl ether, triethylene glycol dimethyl ether, triethylene glycol monoethyl ether, triethylene glycol diethyl ether, tetraethylene glycol monomethyl ether, tetraethylene glycol dimethyl ether or mixtures thereof.

Embodiment 27

The cleaning composition according to embodiment 26, wherein the ether solvents are selected from ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether or a mixture thereof.

Embodiment 28

The cleaning composition according to embodiment 27, wherein the ether solvent is propylene glycol monobutyl ether.

Embodiment 29

The cleaning composition according to any of embodiments 8 to 28, wherein the cleaning composition comprises from 5% to 20%, preferably from 8% to 15% by weight of water.

Embodiment 30

A method for preparing the cleaning composition according to any of embodiments 8 to 29, comprising steps of:

(1) mixing alcohol solvents, ester solvents and ether solvents with stirring uniformly,

(2) further adding corrosion inhibitors with stirring uniformly,

(3) further adding water with stirring uniformly, and

(4) filtering the obtained mixture.

EXAMPLE

Below examples are used to further illustrate the invention without limitations of the protection scope.

Examples 1-3

According to the formulations shown in Table 1 , ethanol, isopropanol, ethyl 3-ethoxypropionate and propylene glycol monobutyl ether were added to a plastic tank with stirring at room temperature and dispersed for 2 minutes, and then NALZIN® FA 179 was added with stirring and dispersed for 2 minutes, then deionized water was added with stirring and dispersed for IQ- 20 minutes until being fully mixed uniformly, finally the resulted mixture was filtered and packaged into a plastic tank and sealed for later use.

Comparative Example 1

According to the formulations shown in Table 1, butyl acetate, propylene glycol methyl ether acetate, xylene, trimethylbenzene, and propylene glycol monobutyl ether were added to a plastic tank with stirring at room temperature and dispersed for 10 minutes until a homogeneous and clear mixed liquid is obtained, then filtered and packaged into a plastic tank and sealed for later use.

Table 1

Tests

The cleaning compositions prepared in Examples 1-3 and Comparative Example 1 were used to perform the following tests on tinplate at room temperature, respectively:

Test 1

Test 1 was carried out without using fingerprints and artificial sweat to contaminate the tinplate, and performed as follows: (1) sanding the tinplate, (2) dusting the tinplate with a cleaning cloth, (3) cleaning contaminates on the tinplate with the cleaning composition, (4) spray coating a paint film on the cleaned tinplate, (5) drying the paint film, (6) placing the tinplate with the paint film into a constant temperature water bath at 40°C for water resistance test and recording water resistance test results (the test duration is 240 hours).

Test 2

Test 2 was carried out under the condition of using finger prints to contaminate the tinplate, and performed as follows: (1) sanding the tinplate, (2) dusting the tinplate with a cleaning cloth, (3) cleaning contaminates on the tinplate with the cleaning composition, (4) using finger prints to contaminate the tinplate, (5) using the cleaning composition to clean the tinplate again, (6) spray coating a paint film on the cleaned tinplate, (7) drying the paint film, (8) placing the tinplate with the paint film into a constant temperature water bath at 40°C for water resistance test and recording water resistance test results (the test duration is 240 hours). Test 3

Test 3 was carried out under the condition of using artificial sweat to contaminate the tinplate, and performed as follows: (1) sanding the tinplate, (2) dusting the tinplate with a cleaning cloth, (3) cleaning contaminates on the tinplate with the cleaning composition, (4) using artificial sweat to contaminate the tinplate, (5) using the cleaning composition to clean the tinplate again, (6) spray coating a paint film on the cleaned tinplate, (7) drying the paint film, (8) placing the tinplate with the paint film into a constant temperature water bath at 40°C for water resistance test and recording water resistance test results (the test duration is 240 hours). The results are shown in Table 2.

Table 2

It can be seen from Table 2 that without using fingerprints or artificial sweat to contaminate the tinplate, the cleaning composition prepared in Examples 1-3 of the present invention has a significantly better stain removal effect than the cleaning composition prepared in Comparative Example 1, such that the paint film has good water resistance. Moreover, with using fingerprints or artificial sweat to contaminate the tinplate, the cleaning composition prepared in Examples 1- 3 of the present invention is more effective in removing grease and sweat than the cleaning composition prepared in Comparative Example 1 , such that the paint film has good water resistance.

It will be apparent to one of ordinary skill in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the present invention. It is intended that the embodiments and examples be considered as exemplary only. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.