JP7777378B2 - Detergent composition and concentrate for the detergent composition - Google Patents

Description

The present invention relates to a cleaning composition and a concentrate for a cleaning composition.

It has long been known that when electronic components such as integrated circuits (ICs) and capacitors are soldered to printed circuit boards, camera module components, etc., flux scatters from the solder paste and adheres to the electrodes as residue (hereinafter, the above-mentioned flux residue may be referred to as "flux residue").

Flux residue can cause corrosion at solder joints, poor bonding during the wire bonding process, and poor adhesion with the molding resin during the resin sealing process. Therefore, flux residue must be removed with a cleaning agent, and various cleaning agents have been proposed (Patent Document 1, Patent Document 2, and Patent Document 3).

Japanese Patent Application Publication No. 05-105899 Japanese Patent Application Laid-Open No. 2002-201492 Japanese Patent Application Publication No. 05-043897

In recent years, there has been a demand for cleaner compositions with improved cleaning and handling properties for flux residue. Furthermore, from the perspective of environmental safety, cleaner compositions with reduced volatile organic compounds (VOCs) are also required. However, with conventional cleaner compositions, it has sometimes been difficult to achieve both improved cleaning and handling properties for flux residue and reduced VOCs. Even when a cleaner composition has excellent cleaning and handling properties for flux residue and reduced VOCs, the organic acids contained in the cleaner composition can easily cause corrosion of metals (e.g., zinc (Zn) and iron (Fe)) contained in the object to be cleaned (in other words, "metal contamination").

The present invention was made in consideration of the above circumstances, and aims to provide a cleaning composition and a concentrate for the cleaning composition that have excellent flux cleaning properties and ease of handling, and that have reduced metal effects and volatile organic compounds (VOCs).

A cleaning composition according to one embodiment of the present disclosure includes a hydrophilic glycol ether compound, an organic acid, a first compound, and water,
the first compound is a hydrophilic nitrogen-containing organic compound and/or a hydrophilic quaternary ammonium salt;
The water content is 20% by mass or more,
The molar ratio of the first compound to the organic acid is 1 or more and 35 or less.

A stock solution for a cleaning composition according to one embodiment of the present disclosure is the stock solution for the cleaning composition described above,
the content of the hydrophilic glycol ether compound is 40% by mass or more and 98.8% by mass or less,
the content of the organic acid is 0.1% by mass or more and 20% by mass or less,
the content of the first compound is 1.1% by mass or more and 40% by mass or less,
It is used by diluting it with water from 1.1 to 20 times.

The present invention makes it possible to provide a cleaning composition and a concentrate for the cleaning composition that have excellent flux cleaning properties and ease of handling, and that have reduced metal effects and volatile organic compounds (VOCs).

Description of the embodiments of the present disclosure
First, embodiments of the present disclosure will be listed and described.
[1] The cleaning composition of the present disclosure comprises:
A cleaning composition comprising a hydrophilic glycol ether compound, an organic acid, a first compound, and water,
the first compound is a hydrophilic nitrogen-containing organic compound and/or a hydrophilic quaternary ammonium salt,
The water content is 20% by mass or more,
The molar ratio of the first compound to the organic acid is 1 or more and 35 or less.

This makes it possible to provide a cleaning composition that has excellent flux cleaning properties and ease of handling, while also reducing metal contamination and volatile organic compounds (VOCs).

[2] In the above [1], the pH of the cleaning composition is preferably 8.0 or more and 12.0 or less. This makes it possible to provide a cleaning composition that is even more excellent in flux removal and handling properties, and that further reduces the effect on metals and volatile organic compounds (VOCs).

[3] In the above [1] or [2], the content of the organic acid is 0.1% by mass or more and 4.0% by mass or less;
The content of the first compound is preferably 1% by mass or more and 20% by mass or less, which makes it possible to provide a cleaning composition that is more excellent in flux removal performance and handling properties, and that has further reduced metal influence and volatile organic compounds (VOCs).

[4] In any of [1] to [3] above, the cleaning composition preferably has a uniform appearance at 25°C and 50°C. This makes it possible to provide a cleaning composition that is even more excellent in flux removal and handling properties, and that further reduces the effect on metals and volatile organic compounds (VOCs).

[5] In any of the above [1] to [4], the organic acid is preferably an organic acid having one or more carboxy groups per molecule, or an organic acid having one or more phosphonic acid groups per molecule. This makes it possible to provide a cleaning composition that is even more excellent in flux removal and handling properties, and that further reduces metal contamination and volatile organic compounds (VOCs).

[6] In any of the above [1] to [5], the hydrophilic glycol ether compound is preferably a compound represented by formula (1) and having a water solubility of more than 50 mass% in an environment at 20°C, or a compound represented by formula (2) and having a water solubility of more than 50 mass% in an environment at 20°C.

(In formula (1), R ¹ , R ² and R ³ each independently represent a hydrogen atom, a methyl group or an ethyl group; R ⁴ represents a linear and/or cyclic hydrocarbon group having 1 to 11 carbon atoms, and —CH ₂ — contained in the hydrocarbon group may be replaced by —O—; in formula (2), R ⁵ and R ⁶ each independently represent a hydrogen atom or a methoxy group, and either R ⁵ or R ⁶ is a methoxy group, and R ⁷ represents a hydrogen atom or a methyl group.) This makes it possible to provide a cleaning composition that is even easier to handle.

[7] In the above [6], the hydrophilic glycol ether compound is preferably at least one compound selected from the group consisting of ethylene glycol monomethyl ether, ethylene glycol monobutyl ether, ethylene glycol monoallyl ether, propylene glycol monopropyl ether, ethylene glycol monoisobutyl ether, ethylene glycol mono-tert-butyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, tripropylene glycol monomethyl ether, diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, diethylene glycol monoisobutyl ether, diethylene glycol monoisopropyl ether, diethylene glycol monobenzyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, diethylene glycol diethyl ether, diethylene glycol isopropyl methyl ether, triethylene glycol monomethyl ether, triethylene glycol monobutyl ether, triethylene glycol dimethyl ether, diethylene glycol monohexyl ether, ethylene glycol monoisopropyl ether, 2-methoxybutanol, 3-methoxybutanol, 3-methoxy-3-methylbutanol, and propyl cellosolve. This makes it possible to provide a cleaning composition that is even easier to handle.

[8] In any one of the above [1] to [7], the organic acid is a hydrophilic acid and/or a hydrophobic acid;
the hydrophilic acid is at least one hydrophilic acid selected from the group consisting of nitrilotris(methylenephosphonic acid), tartaric acid, citric acid, malic acid, glycolic acid, propionic acid, 2-phosphonobutane-1,2,4-tricarboxylic acid, 1-hydroxyethane-1,1-diphosphonic acid, glycine, phytic acid, 1H-benzotriazole-4-carboxylic acid, 1H-benzotriazole-5-carboxylic acid, and p-toluenesulfonic acid;
The hydrophobic acid is preferably at least one selected from the group consisting of diethylenetriaminepentaacetic acid, bicine, ethylenediaminetetra(methylenephosphonic acid), octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, lauric acid, alendronic acid, and 1-amino-2-naphthol-4-sulfonic acid. This makes it possible to provide a cleaning composition that is even more excellent in flux removal performance and handling, and that further reduces the effect on metals and volatile organic compounds (VOCs).

[9] In any of the above [1] to [8],
The hydrophilic nitrogen-containing organic compound is a compound represented by formula (3) and having a water solubility of more than 50 mass% at 20°C, or a compound represented by formula (4) and having a water solubility of more than 50 mass% at 20°C,
The hydrophilic quaternary ammonium salt is preferably a compound represented by formula (5) and having a water solubility of more than 50% by mass in an environment at 20°C.

(In formula (3), R ⁸ represents a —CH ₂ CH ₂ OH group, a —CH ₂ CH(OH)CH ₃ group, a —CH ₂ CH ₂ CH ₂ NH ₂ group, or a chain hydrocarbon group having 1 to 4 carbon atoms; R ⁹ represents a hydrogen atom, a —CH ₂ CH ₂ OH group, a —CH ₂ CH ₂ CH ₂ NH ₂ group, or a —CH ₂ CH(OH)CH ₃ group; R ¹⁰ represents a hydrogen atom, a —CH ₂ CH ₂ OH group, or a methyl group; in formula (4), R ¹⁵ , R ¹⁶ , and R ¹⁷ each independently represent a hydrogen atom or a methyl group; and in formula (5), R ¹¹ , R ¹² , R ¹³ , and R ^{and 14} each independently represent a hydrocarbon group having 1 to 2 carbon atoms.) This makes it possible to provide a cleaning composition that is even more excellent in flux removal properties and handling properties, and that further reduces the effect on metals and volatile organic compounds (VOCs).

[10] In the above [9], the hydrophilic nitrogen-containing organic compound is at least one hydrophilic nitrogen-containing organic compound selected from the group consisting of monoisopropanolamine, 3,3'-diamino-N-methyldipropylamine, 3,3'-diaminodipropylamine, N-ethylethanolamine, diisopropanolamine, diethanolamine, N-n-butyldiethanolamine, triethanolamine, methyldiethanolamine, and 2-methylimidazole;
The hydrophilic quaternary ammonium salt is preferably tetraethylammonium hydroxide, which makes it possible to provide a cleaning composition that is more excellent in flux removal performance and handling properties, and that further reduces the effect on metals and volatile organic compounds (VOCs).

[11] The stock solution for a cleaning composition of the present disclosure is the stock solution for a cleaning composition according to any one of [1] to [10] above,
the content of the hydrophilic glycol ether compound is 40% by mass or more and 98.8% by mass or less,
the content of the organic acid is 0.1% by mass or more and 20% by mass or less,
the content of the first compound is 1.1% by mass or more and 40% by mass or less,
It is used by diluting it with water from 1.1 to 20 times.

This makes it possible to provide a cleaning composition that has excellent flux cleaning properties and ease of handling, while also reducing metal contamination and volatile organic compounds (VOCs).

[Details of the embodiment of the present disclosure]
An embodiment of the present disclosure (hereinafter also referred to as "the present embodiment") will be described. However, the present embodiment is not limited thereto. In this specification, notation in the form of "A to Z" means the upper and lower limits of a range (i.e., A or more and Z or less). When no unit is specified for A and a unit is specified only for Z, the unit of A and the unit of Z are the same.

[Embodiment 1: Cleaning composition]
A cleaning agent composition according to one embodiment of the present disclosure will be described.
The cleaning agent composition according to one embodiment of the present disclosure (hereinafter also referred to as "the present embodiment") comprises:
A cleaning composition comprising a hydrophilic glycol ether compound, an organic acid, a first compound, and water,
the first compound is a hydrophilic nitrogen-containing organic compound and/or a hydrophilic quaternary ammonium salt;
The water content is 20% by mass or more,
The molar ratio of the first compound to the organic acid is 1 or more and 35 or less.

This disclosure makes it possible to provide a cleaning agent composition that has excellent flux removal properties and ease of handling, while also reducing metal contamination and volatile organic compounds (VOCs). The reasons for this are presumed to be as follows:

(a1) The cleaning composition of the present disclosure comprises a hydrophilic glycol ether compound, an organic acid, a first compound, and water. The first compound is a hydrophilic nitrogen-containing organic compound and/or a hydrophilic quaternary ammonium salt, and the molar ratio of the first compound to the organic acid is 1 or more and 35 or less. The combination of the organic acid and the first compound (hydrophilic nitrogen-containing organic compound and/or hydrophilic quaternary ammonium salt) easily creates a polar environment. This increases the stability of the salt formed with the organic acid during cleaning. As a result, not only does the first compound swell and dissolve flux residue, but the formation of the salt improves the flux cleaning properties of the organic acid. Furthermore, the organic acid is less likely to adsorb to metals contained in the object to be cleaned, reducing the impact of the metals.

Furthermore, since the hydrophilic glycol ether and the first compound are hydrophilic, the solubility of the hydrophobic compound in water in the cleaning composition can be increased. Additionally, as described above, the combination of the organic acid with the first compound (hydrophilic nitrogen-containing organic compound and/or hydrophilic quaternary ammonium salt) forms a salt between the first compound and the organic acid, further improving the hydrophilicity of the first compound. Therefore, even when a hydrophobic compound is added to the cleaning composition, the cleaning composition as a whole tends to become uniform, and the cleaning composition has excellent handleability. In the present application, the "handleability" of a cleaning composition is defined as being excellent when no additional work, such as stirring, is required due to separation, or when there are no restrictions on use due to the low safety of the cleaning composition.

(b1) Furthermore, the water content in the cleaning composition is 20% by mass or more. This ensures that the water content in the cleaning composition is sufficiently high, thereby reducing VOCs.

As a result, the cleaning composition according to this embodiment has excellent flux removal properties and ease of handling, while also reducing metal contamination and volatile organic compounds (VOCs).

<Composition of cleaning composition>
<Hydrophilic glycol ether compound>
The cleaning composition contains a hydrophilic glycol ether compound. This can suppress separation from water in the cleaning composition. In this embodiment, the term "glycol ether compound" refers to an ether compound of a dihydric alcohol. In this embodiment, "hydrophilic" refers to a property in which the solubility of water in the target compound exceeds 50% by mass at 20°C. Incidentally, "hydrophobic" refers to a property in which the solubility of water in the target compound is 50% by mass or less at 20°C. The hydrophilic glycol ether compound may be synthesized from known starting materials by known methods. Commercially available hydrophilic glycol ether compounds may be used as they are.

The hydrophilic glycol ether compound is preferably a compound represented by formula (1) and having a water solubility of more than 50 mass% in an environment at 20°C, or a compound represented by formula (2) and having a water solubility of more than 50 mass% in an environment at 20°C.

(In formula (1), R ¹ , R ² and R ³ each independently represent a hydrogen atom, a methyl group or an ethyl group; R ⁴ represents a linear and/or cyclic hydrocarbon group having 1 to 11 carbon atoms, and —CH ₂ — contained in the hydrocarbon group may be replaced with —O—; in formula (2), R ⁵ and R ⁶ each independently represent a hydrogen atom or a methoxy group, and either R ⁵ or R ⁶ is a methoxy group; and R ⁷ represents a hydrogen atom or a methyl group.)

The above hydrophilic glycol ether compounds include ethylene glycol monomethyl ether (MG), ethylene glycol monobutyl ether (BC), ethylene glycol monoallyl ether (AG), propylene glycol monopropyl ether (PFG), ethylene glycol monoisobutyl ether (iBG), ethylene glycol mono-tert-butyl ether (ETB), propylene glycol monomethyl ether (MFG), dipropylene glycol monomethyl ether (MFDG), tripropylene glycol monomethyl ether (MFTG), diethylene glycol monomethyl ether (MDG), diethylene glycol monobutyl ether (BDG), diethylene glycol monoisobutyl ether (iBDG), diethylene glycol monoisopropyl ether (iPDG), diethylene glycol monobenzyl ether (BzDG), ethylene glycol dimethyl ether (DMG), diethylene glycol dimethyl ether (DMDG), diethylene glycol monomethyl ether (DZ ... Preferably, the diethylene glycol dimethyl ether is at least one compound selected from the group consisting of diethylene glycol ethyl methyl ether (MEDG), diethylene glycol diethyl ether (DEDG), diethylene glycol isopropyl methyl ether (IPDM), triethylene glycol monomethyl ether (MTG), triethylene glycol monobutyl ether (BTG), triethylene glycol dimethyl ether (DMTG), diethylene glycol monohexyl ether (HeDG), ethylene glycol monoisopropyl ether (iPG), 2-methoxybutanol (2MB), 3-methoxybutanol (3MB), 3-methoxy-3-methylbutanol (MMB), and propyl cellosolve (PC), and more preferably at least one compound selected from the group consisting of propyl cellosolve, 3-methoxy-3-methylbutanol, dipropylene glycol monomethyl ether, diethylene glycol ethyl methyl ether, and triethylene glycol monobutyl ether.

The content of the hydrophilic glycol ether compound is preferably 5% by mass or more and 78% by mass or less. This further improves the cleaning ability for flux residue. The lower limit of the content of the hydrophilic glycol ether compound is preferably 5% by mass or more, more preferably 15% by mass or more, and even more preferably 20% by mass or more. The upper limit of the content of the hydrophilic glycol ether compound is preferably 78% by mass or less, more preferably 50% by mass or less, and even more preferably 30% by mass or less. The content of the hydrophilic glycol ether compound is preferably 5% by mass or more and 78% by mass or less, more preferably 15% by mass or more and 50% by mass or less, and even more preferably 20% by mass or more and 30% by mass or less.

The content of the hydrophilic glycol ether compound can be determined by gas chromatography analysis under the following conditions.
(Conditions of analysis)
Equipment: Gas chromatograph GC-14B (Shimadzu Corporation)
Detector: Thermal conductivity detector (TCD)
Column: Thermon-3000 (manufactured by Shinwa Chemical Co., Ltd.)
Vaporization chamber temperature: 160°C
Detector temperature: 160°C

<Organic acid>
The cleaning composition contains an organic acid. In this embodiment, the term "organic acid" refers to an acidic organic compound containing a carboxy group, a phosphonic acid group, a sulfo group, or the like. The organic acid may be synthesized from a known starting material by a known method. A commercially available organic acid may be used as is.

The organic acid is an organic acid having one or more carboxyl groups in one molecule, or an organic acid having one or more carboxyl groups in one molecule.
It is preferable that the organic acid having at least one phosphonic acid group is an organic acid having at least one phosphonic acid group. This allows the organic acid to exert a chelating effect on the metal salt in the flux residue and form a stable salt with the first compound, so that the cleaning composition according to this embodiment has excellent flux removal performance and handleability, and can reduce the influence of metals.

The organic acid is a hydrophilic acid and/or a hydrophobic acid, and the hydrophilic acid is at least one hydrophilic acid selected from the group consisting of nitrilotris(methylenephosphonic acid), tartaric acid, citric acid, malic acid, glycolic acid, propionic acid, 2-phosphonobutane-1,2,4-tricarboxylic acid, 1-hydroxyethane-1,1-diphosphonic acid (HEDP), glycine, phytic acid, 1H-benzotriazole-4-carboxylic acid, 1H-benzotriazole-5-carboxylic acid, and p-toluenesulfonic acid. The hydrophobic acid is preferably at least one hydrophobic acid selected from the group consisting of diethylenetriaminepentaacetic acid (DTPA), bicine (DHEG), ethylenediaminetetra(methylenephosphonic acid) (EDTMP), octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, lauric acid, alendronic acid, and 1-amino-2-naphthol-4-sulfonic acid. This allows the compound to exert a chelating effect on the metal salt in the flux residue and form a stable salt with the first compound, so the cleaning composition according to this embodiment has excellent flux removal properties and handleability, and can reduce the influence of metals. The organic acid is a hydrophilic acid and/or a hydrophobic acid, and the hydrophilic acid is at least one hydrophilic acid selected from the group consisting of nitrilotris(methylenephosphonic acid), tartaric acid, citric acid, malic acid, glycolic acid, propionic acid, 2-phosphonobutane-1,2,4-tricarboxylic acid, 1-hydroxyethane-1,1-diphosphonic acid (HEDP), glycine, phytic acid, 1H-benzotriazole-4-carboxylic acid, and 1H-benzotriazole-5-carboxylic acid. It is more preferable that the hydrophobic acid is at least one hydrophobic acid selected from the group consisting of diethylenetriaminepentaacetic acid (DTPA), bicine (DHEG), ethylenediaminetetra(methylenephosphonic acid) (EDTMP), octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, lauric acid, and alendronic acid. These hydrophilic and hydrophobic acids are organic acids having one or more carboxyl groups in one molecule, or one or more phosphonic acid groups in one molecule, and therefore exert a chelating effect on metal salts in flux residues and form stable salts with the first compound. As a result, the cleaning composition of this embodiment has excellent flux removal properties and handleability, and can reduce the effects of metals.

The organic acid content is preferably 0.1% by mass or more and 4.0% by mass or less. This provides even better flux cleaning properties and ease of handling, and further reduces metal effects. The lower limit of the organic acid content is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, and even more preferably 0.5% by mass or more. The upper limit of the organic acid content is preferably 4.0% by mass or less, more preferably 2.0% by mass or less, and even more preferably 1.0% by mass or less. The organic acid content is preferably 0.1% by mass or more and 4.0% by mass or less, more preferably 0.3% by mass or more and 2.0% by mass or less, and even more preferably 0.5% by mass or more and 1.0% by mass or less.

The content of the organic acid can be determined by potentiometric titration under the following conditions:
(conditions)
Apparatus: Automatic potentiometric titrator Model AT-710M (Kyoto Electronics Manufacturing Co., Ltd.)
Measurement temperature: 20℃

<First compound>
The cleaning composition contains a first compound, which is a hydrophilic nitrogen-containing organic compound and/or a hydrophilic quaternary ammonium salt. The saponification action of the hydrophilic nitrogen-containing organic compound and the hydrophilic quaternary ammonium salt cleaves the molecular structure of the resin constituting the flux, making the resin more soluble. This results in even better flux cleaning properties and ease of handling, and further reduces the metal effect. The "first compound" may be synthesized from known starting materials by known methods. A commercially available product may be used as the "first compound" as is.

The hydrophilic nitrogen-containing organic compound is preferably a compound represented by formula (3) and having a water solubility of more than 50 mass% in an environment at 20°C, or a compound represented by formula (4) and having a water solubility of more than 50 mass% in an environment at 20°C.

(In formula (3), R ⁸ represents a —CH ₂ CH ₂ OH group, a —CH ₂ CH(OH)CH ₃ group, a —CH ₂ CH ₂ CH ₂ NH ₂ group, or a chain hydrocarbon group having 1 to 4 carbon atoms; R ⁹ represents a hydrogen atom, a —CH ₂ CH ₂ OH group, a —CH ₂ CH ₂ CH ₂ NH ₂ group, or a —CH ₂ CH(OH)CH ₃ group; R ¹⁰ represents a hydrogen atom, a —CH ₂ CH ₂ OH group, or a methyl group; and in formula (4), R ¹⁵ , R ¹⁶ , and R ¹⁷ each independently represent a hydrogen atom or a methyl group.)

The hydrophilic nitrogen-containing organic compound is preferably at least one hydrophilic nitrogen-containing organic compound selected from the group consisting of monoisopropanolamine (primary amine), 3,3'-diamino-N-methyldipropylamine (primary amine), 3,3'-diaminodipropylamine (primary amine), N-ethylethanolamine (secondary amine), diisopropanolamine (secondary amine), diethanolamine (secondary amine), N-n-butyldiethanolamine (tertiary amine), triethanolamine (tertiary amine), methyldiethanolamine (tertiary amine), and 2-methylimidazole. This swells and dissolves the flux residue, resulting in even better flux cleaning and handling, and further reducing the effects on metals.

The hydrophilic quaternary ammonium salt is preferably a compound represented by formula (5) and having a water solubility of more than 50% by mass in an environment at 20°C.

(In formula (5), R ¹¹ , R ¹² , R ¹³ , and R ¹⁴ each independently represent a hydrocarbon group having 1 to 2 carbon atoms.)

The hydrophilic quaternary ammonium salt is preferably tetraethylammonium hydroxide (TEAH). This swells and dissolves the flux residue, improving the flux cleaning and handling properties and further reducing the effects of metals.

The content of the first compound is preferably 1% by mass or more and 20% by mass or less. If the content is less than 1% by mass, there is a tendency for the cleaning performance to be reduced and for metal contamination to occur. If the content is more than 20% by mass, there is a tendency for the pH to increase, which may compromise worker safety. Therefore, by adjusting the content of the first compound within the above range, it is possible to achieve even better flux cleaning performance and ease of handling, and further reduce metal contamination. The lower limit of the content of the first compound is preferably 1% by mass or more, more preferably 2% by mass or more, and even more preferably 4% by mass or more. The upper limit of the content of the first compound is preferably 20% by mass or less, more preferably 15% by mass or less, and even more preferably 10% by mass or less. The content of the first compound is preferably 1% by mass or more and 20% by mass or less, more preferably 2% by mass or more and 15% by mass or less, and even more preferably 4% by mass or more and 10% by mass or less.

The content of the first compound can be determined by potentiometric titration. The conditions for the potentiometric titration analysis are the same as those for the "organic acid content" analysis described above.

The molar ratio of the first compound to the organic acid is 1 or more and 35 or less. This ensures that the amount of the first compound relative to the organic acid is sufficient, and the organic acid bonds with the first compound, preventing the organic acid from affecting metals in the object to be cleaned. The lower limit of the molar ratio is preferably 1 or more, more preferably 5 or more, and even more preferably 10 or more. The upper limit of the molar ratio is preferably 35 or less, more preferably 30 or less, and even more preferably 25 or less. The molar ratio is preferably 1 or more and 35 or less, more preferably 5 or more and 30 or less, and even more preferably 10 or more and 25 or less.

This molar ratio can be determined by calculation based on the "content of the first compound" determined by the method described above and the "content of the organic acid" determined by the method described above.

<Water>
The cleaning composition contains water. The water is not particularly limited as long as it is water used as a raw material for various industrial products, tap water, or the like. The water may be distilled water or ion-exchanged water. In one aspect of the present embodiment, the water may have an electrical conductivity of 1 to 300 μS/cm, or 1 to 100 μS/cm.

The water content is 20% by mass or more. This allows for reduced VOCs in the cleaning composition of this embodiment. The lower limit of the water content is preferably 25% by mass or more, more preferably 40% by mass or more, and even more preferably 60% by mass or more. The upper limit of the water content is preferably 93% by mass or less, more preferably 80% by mass or less, and even more preferably 75% by mass or less. The water content is preferably 20% by mass or more and 93% by mass or less, more preferably 40% by mass or more and 80% by mass or less, and even more preferably 60% by mass or more and 75% by mass or less.

The water content can be determined by analysis using a Karl Fischer moisture meter under the following conditions:
(Analysis conditions for Karl Fischer moisture meter)
Apparatus: Karl Fischer moisture meter MKS-500 (Kyoto Electronics Manufacturing Co., Ltd.)
Measurement method: Volumetric titration method Measurement temperature: 20℃

<Other ingredients>
The cleaning composition according to this embodiment may further contain other components as long as the effects of the present invention are achieved. Examples of the other components include surfactants, rust inhibitors, pH adjusters, chelating agents, thickeners, wetting agents, evaporation retarders, antioxidants, UV absorbers, pigments, fragrances, and preservatives.

<Characteristics of the cleaning composition>
<pH>
The pH of the cleaning composition is preferably 8.0 or more and 12.0 or less. If the pH is less than 8.0, the cleaning performance of the cleaning composition tends to be reduced and metal effects tend to be easily observed, while if the pH is more than 12.0, worker safety tends to be impaired. Therefore, by adjusting the pH of the cleaning composition within the above range, the flux cleaning performance and handleability can be further improved, and the metal effects can be further reduced. The lower limit of the pH of the cleaning composition is preferably 8.0 or more, more preferably 8.5 or more, and even more preferably 9.0 or more. The upper limit of the pH of the cleaning composition is preferably 12.0 or less, more preferably 11.0 or less, and even more preferably 10.0 or less. The pH of the cleaning composition is preferably 8.0 or more and 12.0 or less, more preferably 8.5 or more and 11.0 or less, and even more preferably 9.0 or more and 10.0 or less.

The pH of the above-mentioned cleaning composition can be determined by the following method. That is, it can be determined by measuring the pH using a pH meter (Docu-PH, manufactured by Sartorius K.K.) at a measurement temperature of 25°C.

<Appearance>
The cleaning composition is preferably uniform in appearance under conditions of 25°C and 50°C. This facilitates handling without special restrictions such as stirring during storage, transportation, and use, resulting in even better handleability. Here, "uniform in appearance" means that the cleaning composition does not appear to separate into two or more layers when left standing. "When left standing" refers to the state when the cleaning composition is maintained for four hours in a state where it is not subjected to external forces other than gravity. More specifically, the "when left standing" can be understood as the state when the cleaning composition is maintained for four hours in a state where it is not shaken, rotated, or stirred. In one aspect of this embodiment, the cleaning composition may be uniform in appearance or may appear to separate into two or more layers at temperatures other than 25°C and 50°C.

<Method for producing cleaning composition>
The method for producing the cleaning composition according to this embodiment includes the steps of preparing the hydrophilic glycol ether compound, the organic acid, the first compound, and water, and adding the hydrophilic glycol ether compound, the organic acid, and the first compound to the water. Any method may be used for the adding step. Examples of the adding step include adding the hydrophilic glycol ether compound, the organic acid, the first compound, and the water to a flask, and adding the hydrophilic glycol ether compound, the organic acid, the first compound, and the water on an industrial scale in a chemical plant or the like.

<How to clean the object>
The method for cleaning an object to be cleaned according to this embodiment includes the steps of:
A method for cleaning an object to be cleaned, comprising contacting the above-mentioned cleaning agent composition with the surface or gap of the object to be cleaned.

The method for contacting the cleaning composition with the surface or gap of the object to be cleaned is not particularly limited. Examples of such methods include immersion, application, and spraying or shower spraying, in the atmosphere, under reduced pressure, or under pressure, at room temperature or under heating. When contacting the cleaning composition with the surface or gap of the object to be cleaned by immersion, stirring, ultrasonic treatment, bubbling, shaking, and other procedures may be performed as necessary. In this method, the object to be cleaned is preferably immersed in a cleaning tank containing the heated cleaning composition. The immersion time is preferably 1 to 60 minutes.

In one aspect of this embodiment, when cleaning gaps in the object to be cleaned, it is preferable to immerse the object to be cleaned in the agitated cleaning composition. In this case, the load on the object to be cleaned tends to be reduced compared to shower cleaning and ultrasonic cleaning.

In the method for cleaning an object to be cleaned according to this embodiment, the temperature of the cleaning composition is preferably 20 to 70°C, more preferably 30 to 60°C, and even more preferably 40 to 50°C.

Then, rinse with water, aqueous alcohol, or aqueous glycol ether, and then dry to remove the cleaning composition from the object to be cleaned.

The cleaning composition according to this embodiment can be suitably used to remove flux residue. That is, the cleaning composition is preferably used for removing flux.

[Embodiment 2: Stock solution for cleaning composition]
A concentrate for a cleaning composition according to one embodiment of the present disclosure will be described.
A concentrate for a cleaning composition according to one embodiment of the present disclosure (hereinafter also referred to as "the present embodiment") comprises:
A concentrate for a cleaning composition according to the first embodiment,
the content of the hydrophilic glycol ether compound is 40% by mass or more and 98.8% by mass or less,
the content of the organic acid is 0.1% by mass or more and 20% by mass or less,
the content of the first compound is 1.1% by mass or more and 40% by mass or less,
It is used by diluting it with water from 1.1 to 20 times.

This disclosure makes it possible to provide a cleaning composition that has excellent flux removal properties and ease of handling, and that has reduced metal effects and volatile organic compounds (VOCs). The cleaning composition according to embodiment 1 can be obtained by diluting the above-mentioned stock solution for the cleaning composition at the above-mentioned ratio (volume ratio).

The present invention will be explained in detail below using examples, but the present invention is not limited to these examples.

<Preparation of cleaning composition>
Cleaning compositions according to Samples 1 to 31, 33 to 54, 101 to 106, 110, and 111 were prepared as follows.

<Preparation process>
As raw materials for producing the cleaning compositions of Samples 1 to 31, 33 to 54, 101 to 106, 110, and 111, the following hydrophilic glycol ether compound, the following organic acid, the following hydrophilic nitrogen-containing organic compound, the following quaternary ammonium salt, and the following water were prepared.
(hydrophilic glycol ether compound)
Propyl cellosolve: manufactured by Dow Chemical Japan Co., Ltd. 3-Methoxy-3-methylbutanol: manufactured by Kuraray Co., Ltd. Dipropylene glycol monomethyl ether: manufactured by Nippon Nyukazai Co., Ltd. Diethylene glycol ethyl methyl ether: manufactured by Nippon Nyukazai Co., Ltd. Triethylene glycol monobutyl ether: manufactured by Nippon Nyukazai Co., Ltd. (organic acid)
Nitrilotrismethylenephosphonic acid (hydrophilic acid): manufactured by Chelest Corporation. Citric acid (hydrophilic acid): manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. Malic acid (hydrophilic acid): manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. Glycolic acid (hydrophilic acid): manufactured by Chemours Inc. Propionic acid (hydrophilic acid): manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. 2-Phosphonobutane-1,2,4-tricarboxylic acid: manufactured by Chelest Corporation. HEDP (hydrophilic acid): manufactured by Chelest Corporation. Glycine (hydrophilic acid): manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. p-Toluenesulfonic acid monohydrate (hydrophilic acid): manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. DTPA: manufactured by Chelest Corporation. DHEG: manufactured by Chelest Corporation. EDTMP: manufactured by Chelest Corporation. Lauric acid: manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. Alendronic acid: manufactured by Tokyo Chemical Industry Co., Ltd. 1-Amino-2-naphthol-4-sulfonic acid: Fujifilm Wako Pure Chemical Industries, Ltd. (hydrophilic nitrogen-containing organic compound)
Monoisopropanolamine (primary amine): manufactured by Tokyo Chemical Industry Co., Ltd. 3,3'-diamino-N-methyldipropylamine (primary amine): manufactured by Tokyo Chemical Industry Co., Ltd. N-ethylethanolamine (secondary amine): manufactured by Nippon Nyukazai Co., Ltd. 2-methylimidazole: manufactured by Tokyo Chemical Industry Co., Ltd. N-n-butyldiethanolamine (tertiary amine): manufactured by Nippon Nyukazai Co., Ltd. Triethanolamine (tertiary amine): manufactured by Tokyo Chemical Industry Co., Ltd. (quaternary ammonium salt)
TEAH: manufactured by Tokyo Chemical Industry Co., Ltd. (hydrophobic nitrogen-containing organic compound)
Dimethylstearylamine: Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. n-Dodecylamine: Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. Di-n-butylamine: Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. 1,2,3-Benzotriazole: Manufactured by Tokyo Chemical Industry Co., Ltd. (Hydrophobic solvent)
Propylene glycol monobutyl ether: Nippon Nyukazai Co., Ltd. Dipropylene glycol dimethyl ether: Nippon Nyukazai Co., Ltd. Dipropylene glycol monobutyl ether: Nippon Nyukazai Co., Ltd. Benzyl alcohol: Tokyo Ohka Kogyo Co., Ltd. (Water)
Distilled water

<Adding step>
Next, the above-mentioned raw materials other than the distilled water (water) were added to the distilled water (water) in the compositions shown in Tables 1 to 4. In the column of "Blended composition [mass %]" in Tables 1 to 4, the components marked with "-" indicate that the component was not contained in the sample.

By carrying out the above steps, cleaning compositions according to Samples 1 to 31, Samples 33 to 54, Samples 101 to 106, Sample 110, and Sample 111, each having the composition shown in Tables 1 to 4, were prepared.

<Evaluation of cleaning agent composition characteristics>
For each sample of the detergent composition, the "pH" was measured, and the "appearance,""cleaningability,""effect on metals," and "handling ease" were evaluated.

<pH>
The pH of each sample cleaning composition was determined by the method described in Embodiment 1. The results are shown in the column "pH (when diluted 100 times with water)" in Tables 1 to 4.

<Appearance>
The appearance of each sample of the cleaning composition was determined by the method described in the first embodiment. The appearance of each sample of the cleaning composition was evaluated both immediately after the sample was prepared and one week after the sample was prepared. The results are shown in the "Appearance" column of Tables 1 to 4.

<Cleaning ability>
The cleaning properties of each sample of the cleaning composition were evaluated according to the following procedure.

(Preparing the test piece)
Test pieces for evaluating cleaning properties were prepared according to the following procedure. First, a 20 mm x 40 mm copper plate (manufactured by Standard Test Piece Co., Ltd.) was prepared. Evaluation paste "MB-T100" (manufactured by Senju Metal Industry Co., Ltd.) was printed on the copper plate. The copper plate was then left to stand on a hot plate at 250°C for 3 minutes to allow reflow. Test pieces were produced according to the above procedure.

(Evaluation test of cleaning ability)
The cleaning performance of each sample cleaning composition was evaluated using the following procedure. First, 400 ml of the cleaning composition was added to a 500 ml beaker and heated to 50°C. Next, the heated cleaning composition was stirred at 500 rpm to disperse the aqueous phase and the organic phase. While maintaining the dispersed state, the test piece was immersed in the cleaning composition. After a predetermined time had elapsed since immersion, the test piece was removed, washed with water, and dried. The surface was observed using a stereomicroscope (magnification: 40x). The time required for complete removal of the flux residue was measured, and the cleaning performance was evaluated according to the following criteria. A cleaning performance rating of A or B indicates high cleaning performance of the cleaning composition. The results are shown in the "Cleanability" column of Tables 1 to 4. However, the areas with burnt flux were excluded from the evaluation.
(Evaluation criteria)
A: The cleaning time is less than 10 minutes.
B: The cleaning time is 10 minutes or more and less than 15 minutes.
C: The cleaning time is 15 minutes or more and less than 20 minutes.
D: The cleaning time is 20 minutes or more and 25 minutes or less.
E: The cleaning time is 25 minutes or more.

The cleaning compositions of Samples 1 to 31 and Samples 33 to 54 are examples. On the other hand, the cleaning compositions of Samples 101 to 106, 110, and 111 are comparative examples. It was confirmed that the cleaning compositions of Samples 1 to 31 and Samples 33 to 54 (examples) have superior cleaning properties compared to Samples 101 to 104 and Sample 110 (comparative example).

<Metallic effects>
The metal influence of each sample of the cleaning composition was evaluated by the following procedure.
(Effect on iron (Fe))
A cold-rolled steel plate SPCC (JIS G 3141:2017) was degreased by immersing it in acetone for 20 minutes. The degreased SPCC was then immersed in each sample of the cleaning agent composition at 50°C for 30 minutes. The SPCC was then rinsed with water, and the change in appearance of the SPCC was visually confirmed, and the effect on iron (Fe) was evaluated in accordance with the "Criteria for evaluating the effect on metals" below.
(Effect on zinc (Zn))
A pure zinc plate was immersed in each sample of the cleaning composition for 30 minutes at 50° C. Then, after rinsing with water, the change in appearance was observed using a stereomicroscope (magnification: 40x), and the effect on zinc (Zn) was evaluated in accordance with the "Criteria for evaluating the effect of metals" below.
(Criteria for assessing the effects of metals)
A: No change observed for 60 minutes or more.
B: A change is observed in 45 minutes or more but less than 60 minutes.
C: A change is observed in 30 minutes or more but less than 45 minutes.
D: A change is observed in 15 minutes or more but less than 30 minutes.
E: A change is observed in less than 15 minutes.

It was confirmed that the cleaning compositions (Examples) of Samples 1 to 31 and Samples 33 to 54 had reduced metal effects compared to Sample 101, Samples 104 to 106, and Sample 111 (Comparative Example).

<Ease of handling>
The uniform appearance of a cleaning composition means that the cleaning composition has excellent "handleability." Here, excellent "handleability" particularly means that additional work, such as stirring, is not required to prevent separation. It was found that the cleaning compositions of Samples 1 to 31 and Samples 33 to 54 (Examples) had uniform appearances, while the cleaning composition of Sample 102 (Comparative Example) did not have a uniform appearance (in other words, separation occurred). Therefore, it was found that the cleaning compositions of Samples 1 to 31 and Samples 33 to 54 (Examples) had superior "handleability" compared to the cleaning composition of Sample 102 (Comparative Example).

<VOC Reduction>
In a cleaning composition, a water content of 20% by mass or more means that the water content is high and that volatile organic compounds (VOCs) are reduced. In the cleaning compositions (Examples) of Samples 1 to 31 and Samples 33 to 54, the water content was 20% by mass or more, and therefore it was found that the VOCs were reduced.

From the above, it was found that the cleaning compositions (Examples) of Samples 1 to 31 and Samples 33 to 54 have excellent flux cleaning properties and ease of handling, and also have reduced metal effects and volatile organic compounds (VOCs).

Although the embodiments and examples of the present invention have been described above, it is also planned from the outset that the configurations of the above-mentioned embodiments and examples may be combined as appropriate.

The embodiments and examples disclosed herein are illustrative in all respects and should not be considered limiting. The scope of the present invention is indicated by the claims, not by the above-described embodiments and examples, and is intended to include all modifications equivalent to and within the scope of the claims.

Claims (1)

A cleaning composition comprising a hydrophilic glycol ether compound, an organic acid, a first compound, and water,
The first compound is a hydrophilic nitrogen-containing organic compound ,
The water content is 20% by mass or more,
a molar ratio of the first compound to the organic acid is 1 or more and 35 or less;
The hydrophilic glycol ether compound is a compound represented by formula (1) and having a water solubility of more than 50 mass% in an environment at 20°C, or a compound represented by formula (2) and having a water solubility of more than 50 mass% in an environment at 20°C,
the hydrophilic glycol ether compound is at least one compound selected from the group consisting of ethylene glycol monomethyl ether, ethylene glycol monobutyl ether, propylene glycol monopropyl ether, ethylene glycol monoisobutyl ether, ethylene glycol mono-tert-butyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, tripropylene glycol monomethyl ether, diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, diethylene glycol monoisobutyl ether, diethylene glycol monoisopropyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, diethylene glycol diethyl ether, diethylene glycol isopropyl methyl ether, triethylene glycol monomethyl ether, triethylene glycol monobutyl ether, triethylene glycol dimethyl ether, diethylene glycol monohexyl ether, ethylene glycol monoisopropyl ether, and propyl cellosolve;
The organic acid is an organic acid having one or more carboxy groups in one molecule,
the hydrophilic nitrogen-containing organic compound is a compound represented by formula (4) and has a solubility in water of more than 50 mass % at 20°C .
(In formula (1), R ¹ , R ² and R ³ each independently represent a hydrogen atom, a methyl group or an ethyl group; R ⁴ represents a linear and/or cyclic hydrocarbon group having 1 to 11 carbon atoms, and —CH ₂ — contained in the hydrocarbon group may be replaced with —O—; in formula (2), R ⁵ and R ⁶ each independently represent a hydrogen atom or a methoxy group, and either R ⁵ or R ⁶ is a methoxy group; and R ⁷ represents a hydrogen atom or a methyl group.)
(In formula (4), R ¹⁵ , R ¹⁶ , and R ¹⁷ each independently represent a hydrogen atom or a methyl group.)