Detergent composition for removing flux residue

Abstract

To provide a detergent composition for flux residue removal which is excellent in removability of flux residue remaining in a gap, in one embodiment.SOLUTION: In one aspect, the disclosed embodiments relate to a cleaning composition for removing flux residue, comprising the following components A, B, and C, wherein the mass ratio of the sum of the components A and B to the components C [(A+ B) / C] is more than 0.9 and less than 7.6: Component A: Glycol ether having a solubility in water at 20 °C of 10% by mass or more Component B: Glycol ether having a solubility in water at 20 °C of less than 10% by mass Component C: Hydrocarbon SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present disclosure relates to a cleaning composition for removing flux residue and a cleaning method using the cleaning composition. [Background technology]

[0002] Soldering is commonly used to mount electronic components on electronic substrates such as printed wiring boards. In recent years, technological innovations have been advancing toward 1) lead-free soldering, 2) finer wiring and solder bumps, and 3) thinner wiring boards to reduce the weight and resource consumption of electronic devices, all with the aim of increasing the processing speed, saving energy, and reducing the emission of environmental pollutants. In particular, 1) the trend toward lead-free soldering has resulted in higher reflow temperatures due to the rise in the melting point of the solder metal. This has made flux more susceptible to degradation and polymerization, making it more difficult to remove. Given this background, there is a demand for cleaning agents that can effectively clean organic residues left behind after high-temperature reflow.

[0003] For example, Patent Document 1 describes hydrocarbons having 10 to 18 carbon atoms: 5 to 85% by weight, R 1 -O-(C n H 2n O) m -R 2 A detergent composition for precision parts or jigs and tools has been proposed, which contains 1 to 80% by weight of a glycol ether compound represented by the following formula: In Patent Document 2, R 1 O-(CH2C(R 3 )HO)-R 2 A cleaning agent for rosin-based solder flux has been proposed, which contains as an active ingredient a mixture of glycol ether represented by the following formula and a hydrocarbon having 8 to 14 carbon atoms. Patent Document 3 proposes a cleaning composition for removing flux residue, which contains: (A) a glycol ether having a boiling point of 200°C or higher and a solubility in water at 20°C of 10 mass% or less; (B) an amino alcohol having a boiling point of 200°C or higher; (C) at least one hydrophobic compound selected from hydrocarbons having 10 to 24 carbon atoms and aliphatic alcohols having 10 to 24 carbon atoms; and (D) water. Patent Document 4 proposes a cleaning composition for removing solder flux residue, which contains diethylene glycol monobutyl ether, diethylene glycol monohexyl ether, a specific amine compound, a polyalkylene glycol alkylamine nonionic surfactant, and water, and in which the diethylene glycol monobutyl ether content is from 40.0 to 54.6% by mass, the diethylene glycol monohexyl ether content is from 40.0 to 54.6% by mass, the specific amine compound content is from 0.3 to 5.0% by mass, and the polyalkylene glycol alkylamine nonionic surfactant content is from 0.1 to 5.0% by mass. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 5-306481 [Patent Document 2] Japanese Patent Application Publication No. 4-65495 [Patent Document 3] Japanese Patent Publication No. 2022-50320 [Patent Document 4] Japanese Patent Application Laid-Open No. 2015-145476 Summary of the Invention [Problem to be solved by the invention]

[0005] In recent years, miniaturization of wiring and solder bumps has led to the mounting of components such as semiconductor packages at high densities. This high density of component mounting leads to high board temperatures during use of equipment equipped with such boards, so solder with a high melting temperature that can withstand high temperatures is used to connect the components. The miniaturization of solder bumps and the higher-than-conventional temperatures during solder melting cause flux denaturation, making the cleaning compositions disclosed in the above patent documents insufficient in removing flux residue (flux removal), and thus their cleaning performance is no longer sufficient. In particular, when other components (e.g., semiconductor chips, chip-type capacitors, other circuit boards, etc.) are stacked and mounted on a circuit board, a space (gap) is formed between the circuit board and the other components. The flux used for the mounting tends to remain in this gap as flux residue after soldering by reflow or the like. In recent years, the length of this gap has tended to become longer, and in particular, in narrow spaces (gaps) where the shortest distance between the circuit board and the other components is several tens of micrometers, the longer the gap length, the more difficult it becomes to clean. Therefore, there is a demand for improved gap cleanability.

[0006] Therefore, the present disclosure provides a cleaning composition for removing flux residue that has excellent removability (gap cleaning ability) for flux residue remaining in gaps, and a cleaning method using the same. [Means for solving the problem]

[0007] In one aspect, the present disclosure relates to a cleaning composition for removing flux residue, comprising the following components A, B, and C, in which the mass ratio of the total of components A and B to component C [(A+B) / C] is more than 0.9 and less than 7.6: Component A: Glycol ether having a solubility in water at 20°C of 10% by mass or more Component B: Glycol ether having a solubility in water at 20°C of less than 10% by mass Component C: Hydrocarbons

[0008] In one aspect, the present disclosure relates to a cleaning method including a cleaning step of cleaning an object having flux residue with the cleaning composition of the present disclosure. [Effects of the Invention]

[0009] According to one aspect, the present disclosure can provide a cleaning composition for removing flux residue that has excellent removability (gap cleaning ability) for flux residue remaining in gaps. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 shows an example of the appearance of a test piece used in a cleaning test, where A is a schematic side view and B is a schematic plan view. DETAILED DESCRIPTION OF THE INVENTION

[0011] This disclosure is based on the finding that flux residue remaining in long crevices can be efficiently removed by using a cleaning composition containing a hydrophilic glycol ether (component A), a hydrophobic glycol ether (component B) and a hydrocarbon (component C) in a specific ratio.

[0012] That is, in one aspect, the present disclosure relates to a cleaning composition for removing flux residue (hereinafter also referred to as "the cleaning composition of the present disclosure") containing the following Components A, B, and C, in which the mass ratio of the total of Components A and B to Component C [(A+B) / C] is more than 0.9 and less than 7.6: Component A: Glycol ether having a solubility in water at 20°C of 10% by mass or more Component B: Glycol ether having a solubility in water at 20°C of less than 10% by mass Component C: Hydrocarbons

[0013] According to the present disclosure, a cleaning composition for removing flux residue that is excellent in the ability to remove flux residue remaining in gaps (gap cleaning ability) can be provided.

[0014] Although the details of the mechanism of action by which the effects of the present disclosure are manifested are still unclear, it is speculated as follows. Generally, glycol ethers dissolve flux residue, but their penetration into gaps is poor and they cannot penetrate gaps efficiently. Therefore, cleaning agents using glycol ethers tend to have poor gap cleaning performance. However, when a glycol ether with a solubility of 10% or more by mass in water at 20°C (hydrophilic glycol ether, component A) is used in combination with a glycol ether with a solubility of less than 10% by mass in water at 20°C (hydrophobic glycol ether, component B) and a hydrocarbon (component C), the penetration of the cleaning agent composition improves, allowing it to penetrate under components and thus improve gap cleaning performance. Although hydrocarbons (component C) have low flux residue solubility, they impart compatibility between components A and B, improving penetration while maintaining flux residue solubility. This is thought to improve gap cleaning performance. Furthermore, when the mass ratio (A+B) / C of the total content of Components A and B to the content of Component C in the cleaning composition of the present disclosure is more than 0.9 and less than 7.6, it is thought that both solubility and penetration of flux residue can be achieved, thereby improving gap cleaning performance. However, the present disclosure need not be construed as being limited to this mechanism.

[0015] In this disclosure, "flux" refers to a rosin-based flux containing rosin or a rosin derivative used in soldering, or a water-soluble flux not containing rosin, which is used to remove oxides that prevent the connection between the metal of an electrode or wiring, etc. and the solder metal, and to promote the connection, and in this disclosure, "soldering" includes reflow and flow soldering. In this disclosure, "solder flux" refers to a mixture of solder and flux. In this disclosure, "flux residue" refers to flux-derived residue remaining on a substrate after solder bumps have been formed using flux and / or on a substrate after soldering using flux. For example, when other components (e.g., semiconductor chips, chip-type capacitors, other circuit boards, etc.) are stacked and mounted on a circuit board, a space (gap) is formed between the circuit board and the other components. The flux used for the mounting may remain in this gap as flux residue after soldering by reflow or the like. In this disclosure, the term "cleaning composition for removing flux residue" refers to a cleaning composition for removing flux residue after forming and / or soldering solder bumps using flux or solder flux. In order to achieve a significant cleaning effect with the cleaning composition according to this disclosure, the solder is preferably a lead (Pb)-free solder containing tin.

[0016] [Component A: glycol ether with a solubility in water of 10% by mass or more at 20°C] The glycol ether (hereinafter also referred to as "component A") having a solubility in water at 20°C of 10 mass % or more contained in the cleaning composition of the present disclosure may be one type or a combination of two or more types. The solubility of component A in water at 20°C is 10% by mass or more, and may be 20% by mass or more, 50% by mass or more, or 80% by mass or more, or the solubility in water at 20°C may be infinite. Note that "infinite" solubility in water at 20°C means that the solubility is 100% by mass or more. In the present disclosure, the solubility of glycol ether in water at 20°C can be measured by the following method. Place 10 g of ion-exchanged water in a glass container, add 1 g of glycol ether, stir for 5 minutes at 20°C, and let stand for 5 minutes. After leaving it to stand, if the appearance of the aqueous solution is uniform and transparent, it is judged to have dissolved. If the appearance of the aqueous solution is cloudy or separated into two or more layers, it is judged to have not dissolved. Specifically, it can be carried out by the method described in the Examples. Glycol ethers having a solubility in water at 20° C. of 10% by mass or more are hydrophilic glycol ethers, and in one or more embodiments, have a hydroxyl group. In one or more embodiments, Component A can be represented by the following formula (I): That is, in one or more embodiments, Component A is a compound represented by the following formula (I).

[0017] <Compound represented by formula (I)> R 1 -O-(R 2 -O) m -H (I) In the above formula (I), R 1 is a hydrogen atom or a straight-chain or branched-chain alkyl group having from 1 to 5 carbon atoms, and from the viewpoint of improving flux residue removability, a straight-chain or branched-chain alkyl group having from 1 to 5 carbon atoms is preferred, a straight-chain or branched-chain alkyl group having from 2 to 5 carbon atoms is more preferred, a straight-chain or branched-chain alkyl group having from 3 to 5 carbon atoms is even more preferred, a straight-chain or branched-chain alkyl group having from 4 to 5 carbon atoms is even more preferred, and a straight-chain alkyl group having from 4 to 5 carbon atoms is even more preferred. R 2 is -CH2-CR 3 H- or -CH2-CH2-CH2-, and from the same viewpoint, -CH2-CR 3 H- is preferred, and -CH2-CH2- is more preferred. R 3 is a hydrogen atom or a methyl group, and from the same viewpoint, a hydrogen atom is preferred. m is an integer of 1 or more and 4 or less, and from the same viewpoint, it is preferably 1 or more and 3 or less, more preferably 1 or 2, and even more preferably 2.

[0018] From the viewpoint of improving flux residue removability, Component A may be at least one selected from diethylene glycol monoalkyl ethers and dipropylene glycol monoalkyl ethers, each having an alkyl group having from 1 to 5 carbon atoms. Preferred examples include diethylene glycol monobutyl ether (BDG, solubility in water at 20°C: infinite), diethylene glycol monomethyl ether (MDG, solubility in water at 20°C: infinite), triethylene glycol monobutyl ether (BTG, solubility in water at 20°C: infinite), and propylene glycol monopropyl ether (PFG, solubility in water at 20°C: infinite).

[0019] The solubility parameter (SP value) δ of component A is set to 20 (J / cm3) from the viewpoint of improving flux residue removal. 1 / 2 More than 20.2 (J / cm3) is preferable. 1 / 2 More preferably, 20.4 (J / cm3) or more 1 / 2 More than 23.0 (J / cm3) is more preferable. Also, from the viewpoint of improving flux residue removal, 1 / 2 Less than 22.0 (J / cm3) is preferable. 1 / 2 Less than 21.0 (J / cm3) is more preferable. 1 / 2 The following is more preferred: In the present disclosure, the solubility parameter (SP value) δ refers to the solubility parameter in Hansen's three-dimensional solubility space shown below. The definition and calculation of the solubility parameter in Hansen's three-dimensional solubility space are described in the document by C. M. Hansen, "The three dimensional solubility parameters," J. Paint Technol., Vol. 39, p. 105 (1967). According to this Hansen space, δD characterizes the London dispersion forces resulting from the formation of dipoles induced during molecular collisions, δp characterizes the Debye interaction forces between permanent dipoles and also the Keesom interaction forces between induced dipoles and permanent dipoles, and δh characterizes specific interaction forces (hydrogen bonding, acid / base, donor / acceptor, etc.), and the solubility parameter δ can be calculated by the following formula: δ=(δD 2 +δp 2 +δh 2 ) 1 / 2 The parameters δp, δh, δD and δ are in units of (J / cm3). 1 / 2 It is expressed as: In the present disclosure, δp, δh, and δD are determined from the structural formula of each compound using "Hansen Solubility Parameters in Practice (HSPiP)," a software for Windows (registered trademark), and the solubility parameter δ is calculated according to the formula.

[0020] The content of Component A when using the cleaning composition of the present disclosure is preferably 30% by mass or more, more preferably 35% by mass or more, and even more preferably 40% by mass or more, from the viewpoint of improving gap cleaning performance for flux residue. Also, from the viewpoint of improving gap cleaning performance for flux residue, the content of Component A is preferably 60% by mass or less, more preferably 55% by mass or less, and even more preferably 50% by mass or less. More specifically, the content of Component A when using the cleaning composition of the present disclosure is preferably 30% by mass or more and 60% by mass or less, more preferably 35% by mass or more and 55% by mass or less, and even more preferably 40% by mass or more and 50% by mass or less. When Component A is a combination of two or more types, the content of Component A refers to the total content of those.

[0021] [Component B: glycol ether with a solubility in water at 20°C of less than 10% by mass] The glycol ether having a solubility in water at 20°C of less than 10 mass% contained in the cleaning composition of the present disclosure (hereinafter also referred to as "Component B") may be one type or a combination of two or more types. The solubility of component B in water at 20° C. is less than 10% by mass, preferably 1% by mass or less, and is preferably 0.05% by mass or more, and more preferably 0.1% by mass or more. Glycol ethers having a solubility in water at 20°C of less than 10% by mass are hydrophobic glycol ethers and can be represented by the following formula (II) or (III): That is, in one or more embodiments, component B is at least one compound selected from the group consisting of compounds represented by the following formula (II) and compounds represented by the following formula (III).

[0022] <Compound represented by formula (II)> R 4 O-(R 5 -O) p -H (II) In the above formula (II), R 4 is a linear or branched alkyl group having 6 to 10 carbon atoms, and from the viewpoint of improving the gap cleaning property of flux residue, a linear or branched alkyl group having 6 to 9 carbon atoms is preferred. R 5 is -CH2-CR 6 H- or -CH2-CH2-CH2-, and from the same viewpoint, -CH2-CR 6 H- is preferred, and -CH2-CH2- is more preferred. R 6 is a hydrogen atom or a methyl group, and from the same viewpoint, a hydrogen atom is preferred. p is an integer of 1 or more and 4 or less, and from the same viewpoint, it is preferably 1 or more and 3 or less, more preferably 1 or 2, and even more preferably 1.

[0023] <Compound represented by formula (III)> R 7 O-(R 9 -O) q -R 8 (III) In the above formula (III), R 7is a linear or branched alkyl group having 4 to 10 carbon atoms, and from the viewpoint of improving the gap cleaning property of flux residue, a linear or branched alkyl group having 4 to 8 carbon atoms is preferred, a linear or branched alkyl group having 4 to 6 carbon atoms is more preferred, and a linear alkyl group having 4 to 6 carbon atoms is even more preferred. R 8 is a linear or branched alkyl group having from 4 to 10 carbon atoms, and from the same viewpoint, is preferably a linear or branched alkyl group having from 4 to 8 carbon atoms, more preferably a linear or branched alkyl group having from 4 to 6 carbon atoms, and even more preferably a linear alkyl group having from 4 to 6 carbon atoms. R 9 is -CH2-CR 10 H- or -CH2-CH2-CH2-, and from the same viewpoint, -CH2-CR 10 H- is preferred, and -CH2-CH2- is more preferred. R 10 is a hydrogen atom or a methyl group, and from the same viewpoint, a hydrogen atom is preferred. q is an integer of 1 or more and 4 or less, and from the same viewpoint, 1 or more and 3 or less is preferable, 1 or 2 is more preferable, and 1 is even more preferable.

[0024] Examples of component B, from the viewpoint of improving gap cleaning properties and flux residue removal properties, include 2-ethylhexyl glycol (EHG, solubility in water at 20°C: 0.2% by mass), hexyl glycol (HeG, solubility in water at 20°C: 1.0% by mass), and diethylene glycol dibutyl ether (DBDG, solubility in water at 20°C: 0.3% by mass).

[0025] The solubility parameter (SP value) of component B is set to 17.0 (J / cm3) from the viewpoint of improving gap cleaning and flux residue removal. 1 / 2 More than 18.0 (J / cm3) is preferable. 1 / 2 More preferably, 19.0 (J / cm3) or more 1 / 2 More preferably, from the same viewpoint, 20 (J / cm3) 1 / 2 Less than 19.8 (J / cm3) is preferable. 1 / 2Less than 19.6 (J / cm3) is more preferable. 1 / 2 The following is more preferred:

[0026] From the viewpoint of separability, the content of component B when using the cleaning composition of the present disclosure is preferably 5% by mass or more, more preferably 7% by mass or more, more preferably 10% by mass or more, and even more preferably 13% by mass or more, and from the viewpoint of improving gap cleaning performance for flux residue, it is preferably 40% by mass or less, more preferably 35% by mass or less, more preferably 30% by mass or less, more preferably 25% by mass or less, more preferably 20% by mass or less, even more preferably 18% by mass or less, and even more preferably 17% by mass or less. More specifically, the content of component B when using the cleaning composition of the present disclosure is preferably 5% by mass or more and 40% by mass or less, 5% by mass or more and 35% by mass or less, 5% by mass or more and 30% by mass or less, or 5% by mass or more and 25% by mass or less, more preferably 7% by mass or more and 20% by mass or less, more preferably 7% by mass or more and 18% by mass or less, even more preferably 10% by mass or more and 18% by mass or less, and even more preferably 13% by mass or more and 17% by mass or less. When component B is a combination of two or more types, the content of component B refers to the total content thereof.

[0027] The mass ratio A / B of component A to component B (content of A / content of B) in the cleaning composition of the present disclosure is preferably 1 or more, more preferably 1.2 or more, even more preferably 1.4 or more, and even more preferably 1.5 or more from the viewpoint of improving gap cleaning performance for flux residue, and is preferably 15 or less, more preferably 10 or less, even more preferably 7 or less, and even more preferably 3.6 or less from the viewpoint of stability of the cleaning composition. More specifically, the mass ratio A / B is preferably 1 or more and 15 or less, more preferably 1.2 or more and 10 or less, even more preferably 1.4 or more and 7 or less, and even more preferably 1.5 or more and 3.6 or less.

[0028] [Component C: Hydrocarbon] The hydrocarbon (hereinafter also referred to as "component C") contained in the cleaning composition of the present disclosure may be one type or a combination of two or more types. From the viewpoint of improving the gap cleaning property of flux residue, the number of carbon atoms in component C is preferably 10 or more, more preferably 12 or more, and even more preferably 13 or more, and from the same viewpoint, it is preferably 18 or less, more preferably 16 or less, and even more preferably 14 or less. In one or more embodiments, from the viewpoint of safety of the cleaning composition, component C is preferably a compound having a flash point of 80° C. or higher. From the same viewpoint, the flash point of component C is preferably 85° C. or higher, more preferably 90° C. or higher, even more preferably 95° C. or higher, and preferably 150° C. or lower, more preferably 130° C. or lower, and even more preferably 110° C. or lower. From the same viewpoint, preferred examples of component C include saturated or unsaturated hydrocarbons having 10 or more carbon atoms, and more preferred examples include unsaturated hydrocarbons having 10 or more carbon atoms. Examples of component C include 1-tetradecene (flash point 113°C), 1-dodecene (flash point 87°C), and 1-hexadecene (flash point 135°C).

[0029] From the viewpoint of improving gap cleaning performance of flux residue, the content of component C during use of the cleaning composition of the present disclosure is preferably 5% by mass or more, preferably 10% by mass or more, preferably 15% by mass or more, more preferably 20% by mass or more, and even more preferably 23% by mass or more. From the same viewpoint, it is preferably 40% by mass or less, more preferably 35% by mass or less, and even more preferably 30% by mass or less. More specifically, the content of component C during use of the cleaning composition of the present disclosure is preferably 5% by mass or more and 40% by mass or less, 10% by mass or more and 40% by mass or less, or 15% by mass or more and 40% by mass or less, more preferably 20% by mass or more and 35% by mass or less, and even more preferably 23% by mass or more and 30% by mass or less. When component C is a combination of two or more types, the content of component C refers to the total content of those components.

[0030] In the cleaning composition of the present disclosure, the mass ratio A / C of Component A to Component C (content of Component A / content of Component C) is preferably 1 or more, more preferably 1.2 or more, and even more preferably 1.4 or more, from the viewpoint of improving the gap cleaning ability of flux residue, and from the same viewpoint, it is preferably 5 or less, more preferably 4 or less, even more preferably 3.9 or less, and even more preferably 3 or less. More specifically, the mass ratio A / C is preferably 1 or more and 5 or less, more preferably 1.2 or more and 4 or less, even more preferably 1.4 or more and 3.9 or less, and even more preferably 1.4 or more and 3 or less.

[0031] In the cleaning composition of the present disclosure, the mass ratio B / C of component B to component C (content of component B / content of component C) is preferably 0.1 or more, more preferably 0.2 or more, from the viewpoint of improving gap cleaning performance for flux residue, and is preferably 2 or less, more preferably 1.5 or less, and even more preferably 1.2 or less, from the viewpoint of stability of the cleaning composition. More specifically, the mass ratio B / C is preferably 0.1 or more and 2 or less, more preferably 0.2 or more and 1.5 or less, and even more preferably 0.2 or more and 1.2 or less.

[0032] In the cleaning composition of the present disclosure, the mass ratio of the total of Components A and B to Component C [(A+B) / C] (total content of Components A and B / content of Component C) is more than 0.9, preferably 1 or more or more than 1, more preferably 1.5 or more, and even more preferably 2 or more, from the viewpoint of improving the gap cleaning ability of flux residue. From the same viewpoint, it is less than 7.6, preferably 7 or less, more preferably 5 or less, and even more preferably 4 or less or less than 4. More specifically, in one or more embodiments, the mass ratio [(A+B) / C] is more than 0.9 and less than 7.6, preferably 1 or more and 7 or less, more preferably 1.5 or more and 5 or less, and even more preferably 2 or more and 4 or less. In one or more embodiments, the mass ratio [(A+B) / C] is preferably more than 0.9 and less than 7.6, preferably 1 or more and 7 or less, more preferably 1.5 or more and 5 or less, and even more preferably 2 or more and 4 or less.

[0033] [Component D: Water] In one or more embodiments, the cleaning composition of the present disclosure may further contain water (hereinafter also referred to as "component D"). Examples of component D include ion-exchanged water, RO water (water treated with a reverse osmosis membrane), distilled water, pure water, and ultrapure water. When the cleaning composition of the present disclosure contains Component D, the content of Component D during use of the cleaning composition of the present disclosure is preferably 5% by mass or more, more preferably 8% by mass or more, from the viewpoints of lowering the flash point and improving the gap cleaning ability of flux residue, and is preferably 20% by mass or less, more preferably 15% by mass or less, from the viewpoints of stability and improving the gap cleaning ability of flux residue. More specifically, the content of Component D in the cleaning composition of the present disclosure is preferably 5% by mass or more and 20% by mass or less, more preferably 8% by mass or more and 15% by mass or less.

[0034] The mass ratio A / D of component A to component D (content of A / content of D) in the cleaning composition of the present disclosure is preferably 2 or more, more preferably 3 or more, and even more preferably 4 or more from the viewpoint of stability of the cleaning composition, and is preferably 10 or less, more preferably 8 or less, more preferably 7 or less, and even more preferably 5.5 or less from the viewpoint of gap cleaning ability for flux residue. More specifically, the mass ratio A / D is preferably 2 or more and 10 or less, more preferably 3 or more and 8 or less, even more preferably 4 or more and 7 or less, and even more preferably 4 or more and 5.5 or less.

[0035] The mass ratio B / D of component B to component D (content of B / content of D) in the cleaning composition of the present disclosure is preferably 0.5 or more, more preferably 1 or more, and even more preferably 1.3 or more from the viewpoint of gap cleaning ability for flux residue, and is preferably 3 or less, more preferably 2 or less, and even more preferably 1.7 or less from the viewpoint of stability of the cleaning composition. More specifically, the mass ratio B / D is preferably 0.5 or more and 3 or less, more preferably 1 or more and 2 or less, and even more preferably 1.3 or more and 1.7 or less.

[0036] In the cleaning composition of the present disclosure, the mass ratio of the total of Components A and B to Component D [(A+B) / D] (total content of Components A and B / content of Component D) is preferably 3 or more, more preferably 5 or more, and even more preferably 6 or more from the viewpoint of improving the gap cleaning ability of flux residue, and from the same viewpoint, it is preferably 20 or less, more preferably 17 or less, and even more preferably 15 or less, 10 or less, 8 or less, or 7 or less. More specifically, the mass ratio [(A+B) / D] is preferably 3 or more and 20 or less, more preferably 5 or more and 17 or less, and even more preferably 6 or more and 15 or less.

[0037] The mass ratio C / D of component C to component D (content of C / content of D) in the cleaning composition of the present disclosure is preferably 1 or more, more preferably 1.5 or more, and even more preferably 2 or more, from the viewpoint of gap cleaning ability for flux residue, and is preferably 5 or less, more preferably 4 or less, and even more preferably 3 or less, from the viewpoint of stability of the cleaning composition. More specifically, the mass ratio C / D is preferably 1 or more and 5 or less, more preferably 1.5 or more and 4 or less, and even more preferably 2 or more and 3 or less.

[0038] [Component E: Amine] From the viewpoint of flux residue removability, the cleaning composition of the present disclosure may further contain at least one amine selected from amino alcohols and aliphatic tertiary amines (hereinafter also referred to as "Component E"). Component E may be one type or a combination of two or more types. In one or more embodiments, the amino alcohol (alkanolamine) may be a tertiary alkanolamine, such as N,N-dibutylethanolamine (dibutylaminoethanol), butyldiethanolamine, or the like. An example of the aliphatic tertiary amine is N,N'-dimethylpalmitylamine. When the cleaning composition of the present disclosure contains Component E, the content of Component E during use of the cleaning composition of the present disclosure is preferably 1% by mass or more, more preferably 3% by mass or more, and even more preferably 4% by mass or more from the viewpoint of flux residue removability, and is preferably 10% by mass or less, more preferably 7% by mass or less, and even more preferably 5% by mass or less from the viewpoint of damage to surrounding components. More specifically, the content of Component E during use of the cleaning composition of the present disclosure is preferably 1% by mass or more and 10% by mass or less, more preferably 3% by mass or more and 7% by mass or less, and even more preferably 4% by mass or more and 5% by mass or less. When Component E is a combination of two or more types, the content of Component E refers to the total content of those components.

[0039] [Component F: Chelating agent] The cleaning composition of the present disclosure can further contain a chelating agent (hereinafter also referred to as "Component F") from the viewpoint of metal residue removability. Component F may be one type or a combination of two or more types. Here, an example of the metal residue is a residue derived from tin contained in reflowed solder (tin oxide residue). In one or more embodiments, tin contained in solder may scatter around the component during the reflow process and remain as tin oxide residue, and the chelating agent can remove the tin oxide residue. Component F includes at least one chelating agent selected from carboxylic acid chelating agents and phosphorus chelating agents. Examples of carboxylic acid chelating agents include hydroxycarboxylic acid chelating agents such as citric acid, malic acid, tartaric acid, and gluconic acid. Examples of phosphorus chelating agents include phosphonic acid chelating agents such as etidronic acid (1-hydroxyethane-1,1-diphosphonic acid). When the cleaning composition of the present disclosure contains component F, the content of component F during use of the cleaning composition of the present disclosure is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, and even more preferably 0.3% by mass or more, from the viewpoint of metal residue removability, and is preferably 1.0% by mass or less, more preferably 0.7% by mass or less, and even more preferably 0.5% by mass or less, from the viewpoint of metal component damage. More specifically, the content of component F during use of the cleaning composition of the present disclosure is preferably 0.1% by mass or more and 1.0% by mass or less, more preferably 0.2% by mass or more and 0.7% by mass or less, and even more preferably 0.3% by mass or more and 0.5% by mass or less. When component F is a combination of two or more types, the content of component F refers to the total content of those components.

[0040] [Other ingredients] The cleaning composition of the present disclosure may contain, as needed, appropriate additives typically used in cleaning agents, such as solvents other than Components A, B, and C, rust inhibitors, thickeners, dispersants, basic substances other than Component E, pH adjusters, polymeric compounds, surfactants, solubilizers, preservatives, disinfectants, antibacterial agents, antifoaming agents, and antioxidants, within the scope that does not impair the effects of the present disclosure.

[0041] In one or more embodiments, the cleaning composition of the present disclosure may be free of a nonionic surfactant having an average HLB of 3 to 18. For example, the content of the nonionic surfactant having an average HLB of 3 to 18 in the cleaning composition of the present disclosure is preferably less than 0.5% by mass, more preferably 0.1% by mass or less, and even more preferably 0% by mass (i.e., no nonionic surfactant is contained).

[0042] [Method of manufacturing the cleaning composition] The cleaning composition of the present disclosure can be produced, for example, by blending component A, component B, component C, and, as needed, optional components (component D, component E, component F, and other components) using a known method. In one or more embodiments, the cleaning composition of the present disclosure can be produced by blending at least component A, component B, and component C. Thus, in one aspect, the present disclosure relates to a method for producing a cleaning composition, which includes a step of blending at least component A, component B, and component C. In the present disclosure, "blending" includes mixing component A, component B, component C, and, as needed, optional components (component D, component E, component F, and other components) simultaneously or in any order. In the method for producing the cleaning composition of the present disclosure, the blending amount of each component can be the same as the content of each component when the above-described cleaning composition of the present disclosure is used. In the present disclosure, the "content of each component of the detergent composition at the time of use" refers to the content of each component at the time of cleaning, i.e., at the time when the detergent composition starts to be used for cleaning.

[0043] The cleaning composition of the present disclosure may be produced and stored as a concentrate from the viewpoints of addition, storage, and transportation. The dilution ratio of the concentrate of the cleaning composition of the present disclosure may be, for example, 3 to 30 times. The concentrate of the cleaning composition of the present disclosure can be used by diluting it with water (component D) so that the contents of components A, B, and C, and optionally component D and other components, are as described above (i.e., the contents at the time of cleaning).

[0044] [pH of cleaning composition] The cleaning composition of the present disclosure is preferably alkaline to improve gap cleaning performance for flux residue, for example, a pH of 7.0 to 14, or 7.0 to 8.5. If necessary, the pH can be adjusted by appropriately blending a desired amount of a basic substance other than Component E, such as an inorganic acid (e.g., nitric acid, sulfuric acid), an organic acid (e.g., oxycarboxylic acid, polycarboxylic acid, aminopolycarboxylic acid, amino acid), or a metal salt or ammonium salt thereof, ammonia, sodium hydroxide, or potassium hydroxide. In the present disclosure, the pH of the cleaning composition is the pH at 25°C when the cleaning composition is in use, and can be measured by the method described in the Examples.

[0045] [Items to be cleaned] The cleaning composition of the present disclosure is used to clean objects having flux residue. Examples of objects having flux residue include objects having reflowed solder. Specific examples of objects to be cleaned include electronic components and their manufacturing intermediates, specifically soldered electronic components and their manufacturing intermediates. More specifically, examples include electronic components soldered with solder and their manufacturing intermediates, electronic components connected via solder and their manufacturing intermediates, electronic components containing flux residue in gaps between soldered components and their manufacturing intermediates, and electronic components containing flux residue in gaps between soldered components and their manufacturing intermediates. The manufacturing intermediates are intermediate products in the manufacturing process of electronic components, including semiconductor packages and semiconductor devices. Examples include circuit boards on which at least one component selected from semiconductor chips, chip capacitors, and circuit boards is mounted by flux soldering, and / or circuit boards on which solder bumps are formed for soldering the components. The gap in the object to be cleaned is, for example, the space formed between a circuit board and a component (semiconductor chip, chip capacitor, circuit board, etc.) soldered and mounted on the circuit board, and refers to a space with a height (distance between components) of, for example, 5 to 500 μm, 10 to 250 μm, or 20 to 100 μm. The width and depth of the gap depend on the size and spacing of the mounted components and electrodes (lands) on the circuit board.

[0046] [Cleaning method] In one aspect, the present disclosure relates to a cleaning method (hereinafter also referred to as the "cleaning method of the present disclosure") that includes a step of cleaning an object having flux residue with the cleaning composition of the present disclosure (hereinafter also referred to as the "cleaning step"). The cleaning step includes contacting the object having flux residue with the cleaning composition of the present disclosure. Examples of methods for contacting an object to be cleaned with the cleaning composition of the present disclosure or cleaning the object with the cleaning composition of the present disclosure include a method for contacting the object in the bath of an ultrasonic cleaning device, a method for contacting the object by spraying the cleaning composition (shower method), etc. The cleaning composition of the present disclosure can be used for cleaning as is without dilution. In one or more embodiments, the cleaning method of the present disclosure preferably includes the steps of contacting the object to be cleaned with the cleaning composition, rinsing the object with water or an alcohol, and drying the object. The cleaning method of the present disclosure can efficiently clean flux residue remaining in gaps between soldered components. From the viewpoint of achieving significant cleaning performance and penetration into narrow gaps using the cleaning method of the present disclosure, it is preferable that the solder be lead (Pb)-free. Furthermore, from the same viewpoint, the cleaning method of the present disclosure is preferably used for electronic components soldered using fluxes described in International Publication No. 2006 / 025224, Japanese Patent Publication No. 6-75796, Japanese Patent Application Laid-Open No. 2014-144473, Japanese Patent Application Laid-Open No. 2004-230426, Japanese Patent Application Laid-Open No. 2013-188761, Japanese Patent Application Laid-Open No. 2013-173184, etc. In the cleaning method of the present disclosure, ultrasonic waves are preferably applied when the cleaning composition of the present disclosure comes into contact with the object to be cleaned, and the ultrasonic waves are more preferably relatively strong, from the viewpoint of making it easier for the cleaning power of the cleaning composition of the present disclosure to be exerted. From the same viewpoint, the ultrasonic frequencies are preferably 26 to 72 Hz and 80 to 1500 W, and more preferably 36 to 72 Hz and 80 to 1500 W.

[0047] [Electronic component manufacturing method] In one aspect, the present disclosure relates to a method for manufacturing an electronic component (hereinafter also referred to as the "electronic component manufacturing method of the present disclosure"), comprising at least one step selected from the steps of mounting at least one component selected from a semiconductor chip, a chip-type capacitor, and a circuit board on a circuit board by soldering using flux and forming solder bumps on the circuit board for connecting the component, etc., and cleaning at least one selected from the circuit board on which the component is mounted and the circuit board on which the solder bumps are formed using the cleaning method of the present disclosure. The flux-based soldering is performed, for example, using lead-free solder and may be performed by either a reflow method or a flow method. Electronic components include semiconductor packages without semiconductor chips mounted thereon, semiconductor packages with semiconductor chips mounted thereon, and semiconductor devices. The electronic component manufacturing method of the present disclosure uses the cleaning method of the present disclosure to reduce flux residue remaining in gaps between soldered components and around solder bumps, thereby suppressing short circuits and poor adhesion between electrodes caused by residual flux, thereby enabling the manufacture of highly reliable electronic components. Furthermore, by performing cleaning using the cleaning method of the present disclosure, flux residue remaining in gaps between soldered components can be easily removed, thereby shortening the cleaning time and improving the manufacturing efficiency of electronic components.

[0048] [kit] In one aspect, the present disclosure relates to a kit for use in the cleaning method of the present disclosure and / or the method for producing electronic components of the present disclosure (hereinafter also referred to as the "kit of the present disclosure"). In one or more embodiments, the kit of the present disclosure is a kit for producing the cleaning composition of the present disclosure. One embodiment of the kit of the present disclosure is a kit (two-liquid cleaning composition) that includes a solution (first liquid) containing components A and B and a solution (second liquid) containing component C in an unmixed state, and that the first and second liquids are mixed at the time of use. The first and second liquids may each contain the optional components described above (component D, component E, component F, and other components) as needed. In one or more embodiments, at least one of the first and second liquids may contain part or all of component D (water). In one or more embodiments, after the first and second liquids are mixed, they may be diluted with component D (water) as needed. [Example]

[0049] The present disclosure will be specifically described below using examples, but the present disclosure is not limited to these examples in any way.

[0050] 1. Preparation of Cleaning Compositions (Examples 1 to 20, Comparative Examples 1 to 5) The components shown in Table 1 were blended in a 100 mL glass beaker and mixed under the conditions below to prepare the cleaning compositions of Examples 1 to 20 and Comparative Examples 1 to 5. Unless otherwise specified, the numerical value for each component in the table indicates the content (% by mass) of the prepared cleaning composition. <Mixing conditions> Liquid temperature: 25℃ Stirrer: Magnetic stirrer (50 mm rotor) Rotation speed: 300 rpm Stirring time: 10 minutes

[0051] The following components are used in the cleaning composition: (Component A) Butyl diglycol (BDG) [Nihon Nyukazai Co., Ltd., diethylene glycol monobutyl ether] (solubility in water at 20°C: infinite, solubility parameter δ: 20.4 (J / cm3) 1 / 2 ) (Component B) 2-Ethylhexyl glycol (EHG) [Nihon Nyukazai Co., Ltd., ethylene glycol mono 2-ethylhexyl ether] (solubility in water at 20°C: 0.2% by mass, solubility parameter δ: 19.0 (J / cm3) 1 / 2 ) Hexyl glycol (HeG) [Nihon Nyukazai Co., Ltd., ethylene glycol monohexyl ether] (solubility in water at 20°C: 1.0% by mass, solubility parameter δ: 19.8 (J / cm3) 1 / 2 ) Dibutyl diglycol (DBDG) [Nihon Nyukazai Co., Ltd., diethylene glycol dibutyl ether] (solubility in water at 20°C: 0.3% by mass, solubility parameter δ: 17.1 (J / cm3) 1 / 2 ) (Component C) 1-Tetradecene [Idemitsu Kosan Co., Ltd., Linearene 14] (carbon number 14, flash point 113°C) 1-Dodecene [Idemitsu Kosan Co., Ltd., Linearene 12] (carbon number 12, flash point 87°C) 1-Hexadecene [Idemitsu Kosan Co., Ltd., Linearene 16] (carbon number 16, flash point 135°C) (Component D) Water [pure water of 1 μS / cm or less produced using the Organo Corporation G-10DSTSET water purification system] (amine) Dibutylethanolamine [Nippon Nyukazai Co., Ltd., Amino Alcohol 2B] Butyldiethanolamine [Nippon Nyukazai Co., Ltd., Amino Alcohol MBD] N,N´-Dimethylpalmitinamine [Tokyo Chemical Industry Co., Ltd.] (chelating agent) Citric acid [Fujifilm Wako Pure Chemical Corporation] Malic acid [Fujifilm Wako Pure Chemical Industries, Ltd.] Etidronic acid [Fujifilm Wako Pure Chemical Industries, Ltd.]

[0052] [Measurement of solubility of glycol ethers (components A and B) in water at 20°C] The solubility of glycol ether in water at 20°C is calculated as follows. Place 10 g of ion-exchanged water in a glass container, add 1 g of glycol ether, stir for 5 minutes at 20°C, and let stand for 5 minutes. After leaving it to stand, if the appearance of the aqueous solution is uniform and transparent, it is judged to have dissolved. If the appearance of the aqueous solution is cloudy or separated into two or more layers, it is judged to have not dissolved. If it is determined that the initial amount added has dissolved, add glycol ether stepwise and continue stirring until it is no longer uniform and transparent, and calculate the solubility using the following formula. Solubility in water at 20°C (mass%) = total mass (g) of glycol ether added until the solution is no longer uniformly transparent / mass (g) of ion-exchanged water × 100 If it is determined that the initial amount is insoluble, the ion-exchanged water is added stepwise and the stirring operation is repeated until the mixture becomes uniform and transparent, and the solubility is calculated using the following formula. Solubility in water at 20°C (mass%) = Mass of glycol ether when it becomes uniformly transparent (g) / Total mass of ion-exchanged water (g) × 100 When the solubility is 100% by mass or more, the solubility in water at 20°C is expressed as "infinite."

[0053] [Solubility parameter δ of glycol ether (components A and B)] Solubility parameter δ of glycol ether (J / cm3) 1 / 2 was calculated using the following formula using the computer software "Hansen Solubility Parameters in Practice (HSPiP)". δ=(δD 2 +δp 2 +δh 2 ) 1 / 2

[0054] [pH measurement] The pH was measured according to the following procedure. 20 g of each cleaning composition was added to a 50 mL glass beaker, and the pH was measured at 25° C. using a pH meter (manufactured by TDK Toa Corporation). The electrode was immersed in the cleaning composition, and the value was read after 3 minutes.

[0055] 2. Evaluation of cleaning composition The prepared cleaning compositions of Examples 1 to 20 and Comparative Examples 1 to 5 were subjected to the following tests to evaluate their gap cleaning properties (flux residue removal properties).

[0056] [Evaluation of gap cleaning ability (flux residue removal)] <Flux residue model used> A commercially available solder flux (Eco Solder M705-BPS9V-T2H (manufactured by Senju Metal Industry Co., Ltd., a mixture of solder metal (Sn-3Ag-0.5Cu)) and flux (a mixture of rosin acid, additives, and solvent)) was placed in a copper container and heated at 250°C for 60 minutes in a N2 atmosphere to remove the solvent, and the flux portion was collected and used as a flux residue model. <Test piece> As shown in Figure 1, the test piece was made by placing a glass plate 2 on a glass epoxy substrate 1 via a spacer, forming a gap 3 (height 30 μm, width (spacer spacing) 16 mm, depth 32 mm). The above-mentioned flux residue model was filled into the gap 3 and used in the cleaning test. <Cleaning method> The cleaning was carried out using an ultrasonic cleaning device (PHENIX+ manufactured by KAIJO, 38 kHz, 300 W). First, the test piece was immersed in the cleaning composition in an ultrasonic cleaning device (60°C, 5 minutes), then immersed in ion-exchanged water for a first rinse (25°C, 3 minutes), and then immersed in fresh ion-exchanged water in the same device for a second rinse (25°C, 3 minutes) (5-minute cleaning). The test piece was then dried in a low-temperature blower dryer (80°C, 5 minutes). <Evaluation method> After drying, the flux residue remaining under the glass plate on the test substrate was measured using the area measurement function of a digital microscope (Keyence VHX-6000) to calculate the area of ​​the flux residue before and after cleaning. The removal rate was calculated using the following formula, and the gap cleaning ability (flux residue removal ability) was evaluated based on the following evaluation criteria. The results are shown in Table 1. Flux residue removal rate (%) = [(area with flux residue before cleaning) - (area with flux residue after cleaning)] / (area with flux residue before cleaning) x 100 <Evaluation criteria> A: Removal rate of 90% or more B: Removal rate is 80% or more but less than 90% C: Removal rate is 70% or more but less than 80% D: Removal rate is 50% or more but less than 70% E: Removal rate less than 50%

[0057] [Table 1]

[0058] As shown in Table 1 above, the cleaning compositions of Examples 1 to 20, in which the mass ratio (A+B) / C was greater than 0.9 and less than 7.6, had superior gap cleaning properties compared to Comparative Example 1, in which the mass ratio (A+B) / C was 7.6, Comparative Example 2, in which the mass ratio (A+B) / C was 0.9, Comparative Example 3, which did not contain component B, Comparative Example 4, which did not contain component A, and Comparative Example 5, in which the mass ratio (A+B) / C was 91.0. [Industrial Applicability]

[0059] The cleaning composition of the present disclosure can efficiently remove flux residue remaining in gaps. This makes it possible, for example, to shorten the flux cleaning step in the semiconductor device manufacturing process and improve the performance and reliability of the manufactured semiconductor devices, thereby improving the productivity of semiconductor devices. [Explanation of symbols]

[0060] 1: Glass epoxy board, 2: Glass plate, 3: Gap

Claims

1. Contains the following components A, B, and C:

1. The cleaning composition for removing flux residue, wherein the mass ratio [(A+B) / C] of the total of component A and component B to component C is more than 0.9 and less than 7.

6. Component A: a glycol ether having a solubility in water at 20°C of 10% by mass or more Component B: a glycol ether having a solubility in water at 20°C of less than 10% by mass Component C: Hydrocarbon

2. 2. The cleaning composition according to claim 1, wherein the mass ratio [(A+B) / C] of the total of component A and component B to component C is 1 or more and 7 or less.

3. 2. The cleaning agent composition according to claim 1, wherein the mass ratio [(A+B) / C] of the total of component A and component B to component C is greater than 1 and less than 4.

4. The cleaning composition according to claim 1 , wherein component A has a hydroxyl group.

5. The cleaning composition according to claim 1, wherein the content of component A is 30% by mass or more and 60% by mass or less.

6. The cleaning composition according to claim 1, wherein the content of component B is 5% by mass or more and 40% by mass or less.

7. The cleaning composition according to claim 1, wherein the content of component C is 5% by mass or more and 40% by mass or less.

8. 10. The cleaning composition of claim 1, further comprising water (component D).

9. The cleaning composition according to claim 8, wherein the content of component D is 5% by mass or more and 20% by mass or less.

10. 9. The cleaning composition according to claim 8, wherein the mass ratio of the total of component A and component B to component D [(A+B) / D] is 3 or more and 20 or less.

11. 2. The cleaning composition according to claim 1, further comprising at least one amine (component E) selected from amino alcohols and aliphatic tertiary amines.

12. The cleaning composition according to claim 11, wherein the content of component E is 1% by mass or more and 10% by mass or less.

13. 10. The cleaning composition of claim 1, further comprising a chelating agent (ingredient F).

14. The cleaning composition according to claim 13, wherein the content of component F is 0.1% by mass or more and 1.0% by mass or less.

15. A cleaning method comprising: a cleaning step of cleaning an object having flux residue with the cleaning agent composition according to any one of claims 1 to 14.

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