TW202120636A - Flux composition comprising maleic-modified rosin ester or maleic-modified rosin amide, and flux and solder paste containing the same - Google Patents

Abstract

The present invention is to provide a soldering flux which is capable of inhibiting the fracture of flux residue and exhibiting excellent solder wettability. The present invention provides a flux composition comprising at least one selected from the group consisting of maleic-modified rosin ester, maleic-modified rosin amide, hydrogenated product of said maleic-modified rosin ester, and hydrogenated product of said maleic-modified rosin amide.

Description

Flux composition containing maleic acid modified rosin ester or maleic acid modified rosin amide, and flux containing the same, and solder paste

The present invention relates to a composition for flux containing maleic acid-modified rosin ester or maleic acid-modified rosin amide, flux containing the same, and solder paste.

The so-called fixing and electrical connection of electronic components in electronic equipment in which electronic components are mounted on a printed circuit board are generally performed by soldering which is the most advantageous in terms of cost and reliability. The methods generally used for this type of soldering are immersion flow soldering in which the printed circuit board and electronic parts are brought into contact with molten solder for soldering, and solder paste, solder preforms or solder balls are reprocessed in a reflow furnace. Reflow welding method for welding by melting.

In this soldering, flux, which is an auxiliary agent, is used in order to make the solder easily adhere to the printed circuit board and electronic components. Flux can play a variety of useful functions such as the following: (1) Metal surface cleaning (chemically remove the oxide film on the metal surface of the printed circuit board and electronic parts to make the surface clean in a solderable way), (2) ) Prevent re-oxidation (cover the cleaned metal surface during soldering to block contact with oxygen, and prevent re-oxidation of the metal surface by heating), (3) Reduce interfacial tension (reduce the surface of molten solder Tension, to improve the wettability of the solder on the metal surface).

Patent Document 1 describes the use of a rosin derivative compound formed by dehydration and condensation of a rosin-based carboxyl group-containing resin and a soft alcohol compound of a dimer acid derivative as a soldering flux. Furthermore, Patent Document 2 discloses a method for efficiently producing rosin ester in a short time. [Prior Technical Literature] [Patent Literature]

Patent Document 1: Japanese Patent Application Publication No. 2014-185298 Patent Document 2: Japanese Patent Application Publication No. 2017-186324

[The problem to be solved by the invention]

However, the flux described in Patent Document 1 generates slag cracks in the flux residue after soldering, and the reliability is poor. On the other hand, when the rosin ester described in Patent Document 2 is used as a flux, there is a problem of low activity and poor wettability.

In view of the foregoing, the object of the present invention is to provide a soldering flux that can suppress the cracking of the residue of the flux residue and is excellent in solder wettability. [Means to solve the problem]

As a result of active research in order to solve the above-mentioned problems, the inventors found that by using a hydrogenated product selected from the group consisting of maleic acid-modified rosin ester, maleic acid-modified rosin amide, the aforementioned maleic acid-modified rosin ester, One or more flux compositions in the group of the aforementioned maleic acid-modified rosin amide hydrides can solve the above-mentioned problems, and the present invention has been completed. That is, the present invention is as follows.

[1] A composition for soldering flux, which contains selected from the group consisting of maleic acid-modified rosin ester, maleic acid-modified rosin amide, the aforementioned maleic acid-modified rosin ester hydride, and the aforementioned maleic acid-modified rosin amide One or more of the group of hydrides. [2] The flux composition of [1] above, wherein the maleic acid-modified rosin ester or maleic acid-modified rosin amide is selected from the group of compounds represented by the following formulas (1) to (7) More than one of them,

(式中，R各獨立表示可經取代之直鏈或分支之烷基、烷二醇基或末端改性聚伸烷氧基，R’各獨立表示可經取代之直鏈或分支之伸烷基或2價烷二醇基)。 [3] 一種用於焊接焊料合金之助焊劑，其包含如上述[1]或[2]之助焊劑用組成物。 [4] 如上述[3]之助焊劑，其中前述馬來酸改性松香酯及/或馬來酸改性松香醯胺之含量，相對於助焊劑全體，為超過0wt%且60wt%以下。 [5] 如上述[3]或[4]之助焊劑，其中前述助焊劑進而包含觸變劑。 [6] 如上述[3]至[5]中任一項之助焊劑，其中前述助焊劑進而包含 0wt%以上20wt%以下之胺， 0wt%以上5wt%以下之有機鹵素化合物， 0wt%以上2wt%以下之胺基氫鹵酸鹽，或 0wt%以上5wt%以下之抗氧化劑， 0wt%以上80wt%以下之樹脂。 [7] 一種焊料糊料，其包含如上述[3]至[6]中任一項之助焊劑及焊料合金。 [8] 如上述[7]之焊料糊料，其中前述焊料合金具有如下之合金組成： As：25~300質量ppm，Bi：0質量ppm以上25000質量ppm以下，Pb：超過0質量ppm且8000質量ppm以下，及其餘部分由Sn所成， 且滿足下述(1)式及(2)式：

[上述(1)式及(2)式中，As、Bi及Pb表示各前述合金組成之含量(質量ppm)]。 [9] 如上述[7]之焊料糊料，其中前述焊料合金具有如下之合金組成： As：25~300質量ppm，Pb：超過0質量ppm且5100質量ppm以下，Sb：超過0質量ppm且3000質量ppm以下，及Bi：超過0質量ppm且10000質量ppm以下之至少1種，其餘部分：由Sn所成， 且滿足下述(3)式及(4)式：

[上述(3)式及(4)式中，As、Sb、Bi及Pb表示各前述合金組成之含量(質量ppm)]。 [發明效果]

(In the formula, R each independently represents a substituted linear or branched alkyl group, an alkanediol group or a terminal modified polyalkoxyl group, and R'each independently represents a substituted linear or branched alkylene group Group or divalent alkylene glycol group). [3] A flux for soldering solder alloys, which includes the flux composition as described in [1] or [2] above. [4] The flux of the above-mentioned [3], wherein the content of the maleic acid-modified rosin ester and/or maleic acid-modified rosin amide is more than 0wt% and 60wt% or less with respect to the whole flux. [5] The flux of the above-mentioned [3] or [4], wherein the aforementioned flux further contains a thixotropic agent. [6] The flux of any one of the above [3] to [5], wherein the aforementioned flux further contains 0wt% to 20wt% of amine, 0wt% to 5wt% of organic halogen compound, 0wt% to 2wt % Of amino hydrohalides, or 0wt% to 5wt% of antioxidants, 0wt% to 80wt% of resin. [7] A solder paste comprising the flux and solder alloy as described in any one of [3] to [6] above. [8] The solder paste of [7] above, wherein the aforementioned solder alloy has the following alloy composition: As: 25~300 mass ppm, Bi: 0 mass ppm or more and 25,000 mass ppm or less, Pb: more than 0 mass ppm and 8000 The mass is below ppm, and the rest is made of Sn, and satisfies the following equations (1) and (2):

[In the above formulas (1) and (2), As, Bi, and Pb represent the content (mass ppm) of each of the aforementioned alloy compositions]. [9] The solder paste of [7] above, wherein the aforementioned solder alloy has the following alloy composition: As: 25 to 300 ppm by mass, Pb: more than 0 ppm by mass and less than 5100 ppm by mass, Sb: more than 0 ppm by mass and 3000 mass ppm or less, and Bi: at least one of more than 0 mass ppm and 10,000 mass ppm or less, the remainder: made of Sn, and satisfy the following equations (3) and (4):

[In the above formulas (3) and (4), As, Sb, Bi, and Pb represent the contents (mass ppm) of the aforementioned alloy compositions]. [Effects of the invention]

According to the present invention, it is possible to provide a soldering flux that can suppress the cracking of the residue of the flux residue and has excellent solder wettability.

Hereinafter, an embodiment of the present invention (hereinafter referred to as "this embodiment") will be described in detail, but the present invention is not limited to this, and various changes can be made without departing from the gist of the present invention.

[Flux] The flux used for soldering solder alloys of this embodiment includes a hydride selected from the group consisting of maleic acid modified rosin ester, maleic acid modified rosin amide, the aforementioned maleic acid modified rosin ester, and the aforementioned maleic acid modified rosin ester. One or more flux compositions and solvents in the group of hydrides of rosin amine hydrides. By using the flux composition of the present embodiment, the cracking of the residue of the flux residue can be suppressed and the solder wettability can be improved. Welding can use either immersion flow welding or reflow welding, but in order to make the effect of the present invention more significant, it is preferably used for reflow welding.

[Maleic acid modified rosin ester/maleic acid modified rosin amide] The flux composition of the present embodiment contains selected from the group consisting of maleic acid-modified rosin ester, maleic acid-modified rosin amide, the aforementioned hydrogenated maleic acid-modified rosin ester, and the aforementioned maleic acid-modified rosin ester One or more of the group of amine hydrides.

The maleic acid-modified rosin ester is not particularly limited, and examples include, for example, maleic acid-modified rosin monomethyl ester, maleic acid-modified rosin monoethyl ester, maleic acid-modified rosin monoisopropyl ester, and maleic acid. Maleic acid-modified rosin monoester such as modified rosin monoglycol ester; maleic acid-modified rosin diester such as maleic acid-modified rosin dimethyl ester, etc. Among these, from the viewpoint of flux activity or compatibility, the monoester of residual carboxylic acid is preferred, and isopropyl ester is particularly preferred.

Examples of maleic acid-modified rosin esters include compounds represented by the following formula (1) or (2).

(In the formula, R represents a linear or branched alkyl group, an alkanediol group or a terminal modified polyalkoxy group which may be substituted).

However, the alkanediol group represents a monovalent group represented by the following formula (i). In the formula (i), ^{each of R 1} independently represents a linear or branched alkylene group with 1 to 4 carbon atoms, and n represents 1 to 500 Integer.

In addition, the terminal modified polyalkoxyl group represents a monovalent group represented by the following formula (ii). In the formula (ii), R ¹ each independently represents a linear or branched alkylene group having 1 to 4 carbon atoms, X Represents an amine group, a linear or branched alkyl ester group with 1 to 40 carbons, or a linear or branched alkyl ether group with 1 to 40 carbons, and n represents an integer from 1 to 500.

The carbon number of the alkyl group represented by R is not particularly limited, but it is preferably 1 to 54. The carbon number of the alkylene glycol group and the terminal modified polyalkoxy group represented by R is not particularly limited, but it is preferably 1 to 500. In the formulas (i) and (ii), the carbon number of the alkyl part of X is preferably 1-24, and the carbon number of ^{R 1 is preferably 1-3.} In addition, in formulas (i) and (ii), n is preferably 1 to 500, more preferably 1 to 100, and still more preferably 1 to 10. Examples of terminal modified polyalkyleneoxy groups are the hydroxyl terminal addition of polyalkylene glycols such as polyethylene glycol, polypropylene glycol, and copolymers of ethylene oxide and propylene oxide, such as cetyl alcohol and stearyl alcohol. And behenyl alcohol with carbon number 1-40 or carboxylic acid group with carbon number 1-40 such as palmitic acid, stearic acid, and behenic acid; and copolymers of ethylene oxide and propylene oxide, etc. The hydroxyl end of the polyalkylene glycol is modified to an amino group.

In addition, as the maleic acid-modified rosin ester, it also includes two or more kinds of maleic acid-modified rosin ester dimer or maleic acid-modified rosin ester polymer represented by the following formula (3). Compounds that are acid-modified rosin esters condensed or bonded via alcohols.

(In the formula, R'represents a linear or branched alkylene group or a divalent alkylene glycol group that may be substituted).

However, the divalent alkanediol group represents a divalent group represented by the following formula (iii). In the formula (iii), R ² and R ³ each independently represent a linear or branched alkylene group having 1 to 4 carbon atoms, n represents an integer from 0 to 500.

The carbon number of the alkylene group represented by R'is not particularly limited, but it is preferably 1 to 54. The carbon number of the divalent alkanediol group represented by R'is not particularly limited, but it is preferably 1 to 500. In the formula (iii), the carbon numbers of ^{R 2} and R ^{3 are preferably 1-3.} Moreover, in formula (iii), n is preferably 1 to 500, more preferably 1 to 100, and still more preferably 1 to 10.

The maleic acid-modified rosin amine is not particularly limited, and examples include cyclohexylamine which is a dehydration condensate of maleic acid-modified rosin and cyclohexylamine, and a dehydration condensate of maleic acid-modified rosin and cyclohexylamine. Salt etc. A specific example is a compound represented by the following formula (4) or (5). Among these, from the viewpoint of flux activity or compatibility, maleic acid-modified rosin monocyclohexylamide and maleic acid-modified hydrogenated rosin cyclohexylamide are preferred.

(式中，R與上述同義)。

(In the formula, R is synonymous with the above).

In addition, the maleic acid-modified rosin amide also includes two or more of maleic acid-modified rosin amide dimer or maleic acid-modified rosin amide polymer represented by the following formula (6) Maleic acid-modified rosin amine condensed or bonded via amine and other compounds.

(式中，R’與上述同義)。

(In the formula, R'has the same meaning as above).

Furthermore, as the maleic acid-modified rosin amide, it also includes a compound in which the maleic acid-modified rosin amide represented by the following formula (7) and the maleic acid-modified rosin ester are bonded directly or via an amine or alcohol. .

(式中，R’與上述同義)。

(In the formula, R'has the same meaning as above).

The maleic acid-modified rosin ester and the maleic acid-modified rosin amide also include various isomers of the above-mentioned compounds (structural isomers, optical isomers, etc.) or salts of the above-mentioned compounds (amine salts, etc.).

Maleic acid-modified rosin ester and maleic acid-modified rosin amide may be used singly, or two or more of them may be used in combination.

The so-called maleic acid-modified rosin ester and maleic acid-modified rosin amide hydride refer to compounds in which the carbon-carbon double bonds existing in these compounds are hydrogenated. For example, the hydrogenated maleic acid modified rosin ester represented by the above formula (1) has a structure represented by the following formula (8).

(式中，R與上述同義)。

(In the formula, R is synonymous with the above).

In addition, the above-mentioned various maleic acid-modified rosin esters and maleic acid-modified rosin amides can be produced using conventional methods. As a conventional method, for example, the solvent-free reaction described in Example 1 of JP 2017-186324 A, or the reaction in a hydrophobic solvent of Example 6 can be used. Examples of the raw material rosin used in the synthesis of maleic acid-modified rosin ester and maleic acid-modified rosin amide include rosin gum, tall oil rosin, wood rosin, and their purified products (purified rosin). As the raw material rosin, for example, raw rosin described in "D.F. Zinkel, J. Russell, translated by Yoshihiro Hasegawa (1993), Pine Chemical Production, Chemistry and Application, 361-362" or commercially available rosin gum can be used. That is, the maleic acid-modified rosin ester and the maleic acid-modified rosin amide of this embodiment may also include rosin derived from the above-mentioned various raw material rosin and (hydrogenated) maleic acid-modified rosin, etc. A compound obtained by esterification or amination.

The content of maleic acid-modified rosin ester and maleic acid-modified rosin amide, relative to the total flux, is preferably more than 0wt% and 60wt% or less, more preferably 5wt% or more, and still more preferably 10wt% or more , Still more preferably 20wt% or more, particularly preferably 30wt% or more, and the upper limit is preferably 50wt% or less, more preferably 40wt% or less. The higher the content of maleic acid-modified rosin ester and maleic acid-modified rosin amide, the more significant the effect of inhibiting the cracking of the flux residues becomes more pronounced.

The flux of this embodiment may also contain the above-mentioned maleic acid-modified rosin ester, maleic acid-modified rosin amide, and resins other than these hydrides. As the resin, various resins used in conventional soldering fluxes can be used. Examples of these resins include rosin resins, acrylic resins, polyesters, polyethylene, polypropylene, polyamides, styrene-maleic acid copolymers, acrylic resins, epoxy resins, phenol resins, and phenoxy resins. , Terpene resins, terpene phenol resins and mixtures of these, among which rosin-based resins are generally used. Examples of rosin-based resins include natural rubber such as rosin gum and wood rosin, or derivatives thereof (polymerized rosin, hydrogenated rosin, disproportionated rosin, acid-modified rosin, rosin ester, etc.).

The resin content in the flux is not limited. When used as a flux for reflow soldering, for example, it can be set within the range of 10~80% by mass, or within the range of 20~70% by mass. It can be set within the range of 30-60% by mass. When used as a flux for immersion welding, for example, it can be set within the range of 3-18% by mass, or within the range of 6-15% by mass, or within the range of 9-12% by mass. .

Examples of the solvent contained in the flux of this embodiment include water, alcohol-based solvents, glycol ether-based solvents, and terpineols. Examples of alcohol-based solvents include isopropanol, 1,2-butanediol, isobornyl cyclohexanol, 2,4-diethyl-1,5-pentanediol, and 2,2-dimethyl-1 ,3-propanediol, 2,5-dimethyl-2,5-hexanediol, 2,5-dimethyl-3-hexyne-2,5-diol, 2,3-dimethyl-2 ,3-Butanediol, 1,1,1-tris(hydroxymethyl)ethane, 2-methyl-2-hydroxymethyl-1,3-propanediol, 2,2'-oxybis(methylene Base) bis(2-ethyl-1,3-propanediol), 2,2-bis(hydroxymethyl)-1,3-propanediol, 1,2,6-trihydroxyhexane, bis(2,2, 2-Tris(hydroxymethyl)ethyl)ether, 1-ethynyl-1-cyclohexanol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, erythritol, threose Alcohol, guaiacol glyceryl ether, 3,6-dimethyl-4-octyne-3,6-diol, 2,4,7,9-tetramethyl-5-decyne-4 , 7-diol and so on. Examples of glycol ether solvents include hexyl diethylene glycol, diethylene glycol mono-2-ethylhexyl ether, ethylene glycol monophenyl ether, 2-methylpentane-2,4-diol, and diethylene glycol. Alcohol monohexyl ether, diethylene glycol dibutyl ether, triethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, etc.

The flux of this embodiment may further contain organic acids, amines, and halogens (organic halogen compounds, amine hydrohalides) as activating agents. When the flux of this embodiment is used as a flux for reflow soldering, it is preferable to contain 0wt% or more and 10wt% or less of organic acid. When the flux of this embodiment is used as a soldering flux for reflow, it preferably contains 0wt% or more and 20wt% or less of amine, more preferably 0wt% or more and 5wt% or less of amine. When the flux of this embodiment is used as a flux for reflow soldering, it preferably contains 0wt% or more and 5wt% or less of an organic halogen compound as a halogen, and preferably contains 0wt% or more and 2wt% or less of amine hydrohalic acid salt. When the flux of this embodiment is used as a flux for immersion welding, it preferably contains 0.1wt% or more and 12.0wt% or less of active agent, more preferably 0.3wt% or more and 8.0wt% or less, and more preferably 0.5 Above wt% and below 4.0wt%.

Examples of organic acids are glutaric acid, adipic acid, azelaic acid, eicosandioic acid, citric acid, glycolic acid, succinic acid, salicylic acid, diglycolic acid, dipicolinic acid, dibutylaniline diethanol Acid, suberic acid, sebacic acid, thioglycolic acid, terephthalic acid, dodecanedioic acid, phthalic acid, fumaric acid, maleic acid, malonic acid, lauric acid, benzoic acid, tartaric acid , Tris(2-carboxyethyl) isocyanurate, glycine, 1,3-cyclohexanedicarboxylic acid, 2,2-bis(hydroxymethyl)propionic acid, 2,2-bis(hydroxyl (Methyl) butyric acid, 2,3-dihydroxybenzoic acid, 2,4-diethylglutaric acid, 2-quinolinecarboxylic acid, 3-hydroxybenzoic acid, malic acid, p-methoxybenzoic acid, hard Fatty acid, 12-hydroxystearic acid, oleic acid, linoleic acid, linolenic acid, etc.

In addition, examples of organic acids include dimer acid, trimer acid, hydrogenated dimer acid of hydrogenated hydrogenated p-dimer acid, and hydrogenated trimer acid of hydrogenated hydrogenated p-trimer acid.

For example, for example, dimer acid of the reactant of oleic acid and linoleic acid, trimer acid of the reactant of oleic acid and linoleic acid, dimer acid of the reactant of acrylic acid, trimer acid of the reactant of acrylic acid, Dimer acid of the reactant of methacrylic acid, trimer acid of the reactant of methacrylic acid, dimer acid of the reactant of acrylic acid and methacrylic acid, trimer acid of the reactant of acrylic acid and methacrylic acid, oleic acid The dimer acid of the reactant, the trimer acid of the reactant of oleic acid, the dimer acid of the reactant of linoleic acid, the trimer acid of the reactant of linoleic acid, the dimer acid of the reactant of linolenic acid, Trimer acid of the reactant of linolenic acid, dimer acid of the reactant of acrylic acid and oleic acid, trimer acid of the reactant of acrylic acid and oleic acid, dimer acid of the reactant of acrylic acid and linoleic acid, acrylic acid and linoleic acid Trimer acid of the reactant of oleic acid, dimer acid of the reactant of acrylic acid and linolenic acid, trimer acid of the reactant of acrylic acid and linolenic acid, dimer acid of the reactant of methacrylic acid and oleic acid, methyl Trimer acid of the reactant of acrylic acid and oleic acid, dimer acid of the reactant of methacrylic acid and linoleic acid, trimer acid of the reactant of methacrylic acid and linoleic acid, reaction of methacrylic acid and linolenic acid Dimer acid, the trimer acid of the reactant of methacrylic acid and linolenic acid, the dimer acid of the reactant of oleic acid and linolenic acid, the trimer acid of the reactant of oleic acid and linolenic acid, linoleic acid and The dimer acid of the reactant of linolenic acid, the trimer acid of the reactant of linoleic acid and linolenic acid, the hydrogenated dimer acid of the hydrogenated products of the above dimer acids, the hydrogenated trimerization of the hydrogenated products of the above-mentioned trimer acids Sour etc.

Examples of amines include monoethanolamine, diphenylguanidine, xylylguanidine, ethylamine, triethylamine, cyclohexylamine, ethylenediamine, triethylenetetramine, 2-methylimidazole, 2-undecane Base imidazole, 2-heptadecyl imidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1- Benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1- Cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-tri Oxazine, 2,4-diamino-6-[2'-undecylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2' -Ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-methylimidazolyl-(1')] -Ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4 -Methyl-5-hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole, 1-dodecyl-2-methyl-3-benzene chloride Bisimidazolium, 2-methylimidazoline, 2-phenylimidazoline, 2,4-diamino-6-vinyl-s-triazine, 2,4-diamino-6-vinyl-s -Triazine isocyanuric acid adduct, 2,4-diamino-6-methacryloxy-s-triazine, epoxy-imidazole adduct, 2-methylbenzimidazole, 2-octylbenzimidazole, 2-pentylbenzimidazole, 2-(1-ethylpentyl)benzimidazole, 2-nonylbenzimidazole, 2-(4-thiazolyl)benzimidazole, Benzimidazole, 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-3'-tertiary butyl-5'-methylphenyl)- 5-Chlorobenzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)benzotriazole, 2-(2'-hydroxy-5'-tert-octyl Phenyl)benzotriazole, 2,2'-methylenebis[6-(2H-benzotriazol-2-yl)-4-third octylphenol], 6-(2-benzo Triazolyl)-4-tert-butyl-6'-tert-butyl-4'-methyl-2,2'-methylene bisphenol, 1,2,3-benzotriazole, 1- [N,N-bis(2-ethylhexyl)aminomethyl]benzotriazole, carboxybenzotriazole, 1-[N,N-bis(2-ethylhexyl)aminomethyl]methan Benzotriazole, 2,2'-[[(methyl-1H-benzotriazol-1-yl)methyl]imino]diethanol, 1-(1',2'-dicarboxyethyl Yl)benzotriazole, 1-(2,3-dicarboxypropyl)benzotriazole, 1-((2-ethylhexylamino)methyl ]Benzotriazole, 2,6-bis[(1H-benzotriazol-1-yl)methyl]-4-methylphenol, 5-methylbenzotriazole, 5-phenyltetrazole, etc. .

Examples of organic halogen compounds include trans-2,3-dibromo-2-butene-1,4-diol, triallyl isocyanurate 6 bromide, 1-bromo-2-butanol, 1 -Bromo-2-propanol, 3-bromo-1-propanol, 3-bromo-1,2-propanediol, 1,4-dibromo-2-butanol, 1,3-dibromo-2-propanol , 2,3-dibromo-1-propanol, 2,3-dibromo-1,4-butanediol, 2,3-dibromo-1,4-butanediol, 2,3-dibromo- 2-Butene-1,4-diol, tris(2,3-dibromopropyl) isocyanurate, chlorogenic anhydride, etc.

It is a compound obtained by reacting amine and hydrogen halide as an amine hydrohalide. As the amine of the amine hydrohalide, the above-mentioned amines can be used, for example ethylamine, cyclohexylamine, ethylenediamine, triethylamine, diphenylguanidine, xylylguanidine, methylimidazole, 2-ethyl- 4-methylimidazole and so on. Examples of hydrogen halides include chlorine, bromine, iodine, and fluorine hydrides (hydrogen chloride, hydrogen bromide, hydrogen iodide, and hydrogen fluoride). In addition, borofluoride may be contained instead of amine hydrohalide, or borofluoride may be contained together with amine hydrohalide. Examples of the borofluoride include borohydrofluoric acid. Examples of amine hydrohalides include aniline hydrogen chloride, cyclohexylamine hydrogen chloride, aniline hydrogen bromide, diphenylguanidine hydrogen bromide, xylylguanidine hydrogen bromide, ethylamine hydrogen bromide, and the like.

The flux of this embodiment may further contain antioxidants. Examples of antioxidants include hindered phenol-based antioxidants. When used as soldering fluxes for reflow, it is preferable to contain 0wt% to 5wt% of antioxidants as the dipping agent. When the flux is used, it preferably contains 0wt% or more and 5wt% or less of antioxidant, more preferably 0wt% or more and 2wt% or less.

The flux of this embodiment may also contain a thixotropic agent. Examples of thixotropic agents include wax-based thixotropic agents, arylamide-based thixotropic agents, and sorbitol-based thixotropic agents. As the wax-based thixotropic agent, for example, castor oil is exemplified. Examples of arylamide-based thixotropic agents include mono-arylamide-based thixotropic agents, diarylamide-based thixotropic agents, and polyaramide-based thixotropic agents, and specific examples are arylamide laurate and aryl palmitate. Amines, stearic acid arylamides, behenic acid arylamides, hydroxystearic acid arylamides, saturated fatty acid arylamides, oleic acid arylamides, erucic acid arylamides, unsaturated fatty acid arylamides, p- -Toluene methane arylamide, aromatic arylamide, methylene bisstearic acid arylamide, ethylenebislauric acid arylamide, ethylenebishydroxystearic acid arylamide, saturated fatty acid diaromatic Amide, methylene bisoleic acid arylamide, unsaturated fatty acid bisarylamide, meta-xylene bisstearic acid arylamide, aromatic bisarylamide, saturated fatty acid polyaramide, unsaturated fatty acid Polyaramide, aromatic polyaramide, substituted aramide, methylol stearate aramide, methylol aramide, fatty acid ester aramide, etc. Examples of sorbitol-based thixotropic agents include dibenzylidene-D-sorbitol, bis(4-methylbenzylidene)-D-sorbitol, and the like.

Moreover, the flux of this embodiment may contain an ester compound as a thixotropic agent. As the ester compound, for example, castor oil is exemplified.

The total amount of the thixotropic agent contained in the flux, when used as a soldering flux for reflow, preferably contains 0wt% or more and 15wt% or less, more preferably 0wt% or more and 10wt% or less. In addition, the content of arylamine thixotropic agent, when used as a soldering flux for reflow, preferably contains 0wt% to 12wt%, and the content of ester compound, when used as a soldering flux for reflow , Preferably contains 0wt% or more and 8.0wt% or less, and more preferably contains 0wt% or more and 4.0wt% or less. The total amount of the thixotropic agent contained in the flux, when used as a soldering flux for immersion flow, preferably contains 0wt% or more and 3wt% or less, more preferably 0wt% or more and 1wt% or less.

[Solder Paste] The flux of this embodiment can be used for either dip flow soldering or reflow soldering. However, in order to have a tendency to make the effect of the present invention more pronounced, it is preferably used for reflow soldering.

[上述(1)式及(2)式中，As、Bi及Pb表示各前述合金組成之含量(質量ppm)]。The solder paste of the first embodiment contains the above-mentioned flux and solder alloy. The solder alloy is not particularly limited, but preferably has the following alloy composition: As: 25 to 300 mass ppm, Bi: 0 mass ppm or more and 25,000 mass ppm or less, Pb: more than 0 mass ppm and 8000 mass ppm or less, and others Part of it is formed by Sn and satisfies the following (1) and (2):

[In the above formulas (1) and (2), As, Bi, and Pb represent the contents (mass ppm) of the aforementioned alloy compositions].

[上述(3)式及(4)式中，As、Sb、Bi及Pb表示各前述合金組成之含量(質量ppm)]。The solder alloy of the second embodiment is not particularly limited, but preferably has the following alloy composition: As: 25 to 300 ppm by mass, Pb: more than 0 ppm by mass and 5100 ppm by mass or less, Sb: more than 0 ppm by mass and 3000 mass ppm or less, and Bi: at least one of more than 0 mass ppm and 10,000 mass ppm or less, the remainder: made of Sn, and satisfy the following equations (3) and (4):

[In the above equations (3) and (4), As, Sb, Bi, and Pb represent the contents (mass ppm) of the aforementioned alloy compositions].

As is an element that can inhibit the viscosity of solder paste from changing over time. It is estimated that As has low reactivity with flux and is a noble element relative to Sn, it can exhibit the effect of suppressing viscosity increase. If As is less than 25 mass ppm, the effect of suppressing thickening cannot be sufficiently exhibited. The lower limit of the As content is 25 mass ppm or more, preferably 50 mass ppm or more, and more preferably 100 mass ppm or more. On the other hand, when there is too much As, the wettability of the solder alloy deteriorates. The upper limit of the As content is 300 ppm by mass or less, preferably 250 ppm by mass or less, and more preferably 200 ppm by mass or less.

Sb is an element whose reactivity with flux is low and shows the effect of suppressing viscosity increase. When the solder alloy of this embodiment contains Sb, the lower limit of the Sb content is more than 0 mass ppm, preferably 25 mass ppm or more, more preferably 50 mass ppm or more, still more preferably 100 mass ppm or more, particularly preferably 300 Mass ppm or more. On the other hand, when the Sb content is too large, the wettability deteriorates, so it must be set to an appropriate content. The upper limit of the Sb content is 3000 mass ppm or less, preferably 1150 mass ppm or less, and more preferably 500 mass ppm or less.

Bi and Pb, like Sb, are elements that have low reactivity with flux and exhibit viscosity-inhibiting effects. In addition, Bi and Pb are elements that can reduce the wettability of As by lowering the liquidus temperature of the solder alloy.

If at least one element of Sb, Bi, and Pb is present, the deterioration of the wettability of As can be suppressed. When the solder alloy of this embodiment contains Bi, the lower limit of the Bi content is more than 0 mass ppm, preferably 25 mass ppm or more, more preferably 50 mass ppm or more, still more preferably 75 mass ppm or more, particularly preferably 100 Mass ppm or more, preferably 250 mass ppm or more. When the solder alloy of this embodiment contains Pb, the lower limit of the Pb content is more than 0 mass ppm, preferably 25 mass ppm or more, more preferably 50 mass ppm or more, still more preferably 75 mass ppm or more, particularly preferably 100 Mass ppm or more, preferably 250 mass ppm or more.

On the other hand, when the content of these elements is too large, the solidus temperature is significantly lowered, so the ΔT of the temperature difference between the liquidus temperature and the solidus temperature becomes too wide. When the ΔT is too wide, during the solidification process of the molten solder, the Bi or Pb in the liquid phase is concentrated due to the low content of Bi or Pb and the precipitation of a high melting point crystalline phase. Subsequently, if the temperature of the molten solder alloy is further reduced, the concentration of Bi or Pb will increase and the low melting point crystal phase will be segregated. Therefore, the mechanical strength of the solder alloy is deteriorated, and the reliability is deteriorated. In particular, since the Bi concentration is high and the crystalline phase is hard and brittle, if it segregates in the solder alloy, the mechanical strength and the like are significantly reduced.

Based on these viewpoints, when the solder alloy of the present embodiment contains Bi, the upper limit of the Bi content is 25,000 mass ppm or less, preferably 10,000 mass ppm or less, more preferably 1,000 mass ppm or less, and still more preferably 600 mass ppm or less , Particularly preferably below 500 mass ppm. When the solder alloy of this embodiment contains Pb, the upper limit of the Pb content is 8000 mass ppm or less, preferably 5100 mass ppm or less, more preferably 5000 mass ppm or less, and still more preferably 1000 mass ppm or less, particularly preferred It is 850 ppm by mass or less, preferably 500 ppm by mass or less.

The solder alloy of the first embodiment preferably satisfies the following formula (1).

上述(1)式中，As、Bi及Pb表示各合金組成之含量(質量ppm)。

In the above formula (1), As, Bi, and Pb represent the content (mass ppm) of each alloy composition.

As, Bi, and Pb are all elements that exhibit viscosity-increasing inhibitory effects. The total amount of these is preferably 230 mass ppm or more. (1) In the formula, the As content is doubled because As has a higher viscosity-increasing inhibitory effect than Bi or Pb.

(1) When the formula does not reach 275, the viscosity increase suppression effect cannot be fully exerted. (1) The lower limit of the formula is 275 or more, preferably 300 or more, more preferably 700 or more, and still more preferably 900 or more. On the other hand, the upper limit of the formula (1) is not particularly limited in terms of the effect of thickening suppression, but from the viewpoint of keeping ΔT in an appropriate range, it is preferably 25200 or less, more preferably 15200 or less, and still more preferably 10200 Below, it is particularly preferably 8200 or less, and most preferably 5300 or less.

From the above-mentioned preferred aspects, the upper and lower limits are appropriately selected to satisfy the following formulas (1a) and (1b).

上述(1a)式及(1b)式中，As、Bi及Pb表示各合金組成之含量(質量ppm)。

In the above formulas (1a) and (1b), As, Bi, and Pb represent the content (mass ppm) of each alloy composition.

The solder alloy of the first embodiment preferably satisfies the following formula (2).

上述(2)式中，Bi及Pb表示各合金組成之含量(質量ppm)。

In the above formula (2), Bi and Pb represent the content (mass ppm) of each alloy composition.

Although Bi and Pb can suppress the deterioration of wettability due to the content of As, if the content is too large, ΔT will increase, so strict management is required. Especially in an alloy composition containing both Bi and Pb, ΔT tends to increase. In the first embodiment, the increase in ΔT can be suppressed by prescribing the sum of the values obtained by multiplying the contents of Bi and Pb by a specific coefficient. (2) In the formula, the coefficient of Pb is greater than the coefficient of Bi. The reason is that Pb has a greater contribution to ΔT compared with Bi, and ΔT can be greatly increased by only a small increase in content.

(2) The solder alloy with formula 0 does not contain two elements of Bi and Pb, and cannot suppress the deterioration of wettability due to the inclusion of As. (2) The lower limit of the formula exceeds 0, preferably 0.02 or more, more preferably 0.03 or more, still more preferably 0.05 or more, particularly preferably 0.06 or more, and most preferably 0.11 or more. On the other hand, since the ΔT temperature range when the formula (2) exceeds 7 becomes too wide, the concentration of Bi or Pb increases when the molten solder is solidified, and the crystal phase segregates, which deteriorates mechanical strength and the like. (2) The upper limit is 7 or less, preferably 6.56 or less, more preferably 6.40 or less, still more preferably 5.75 or less, still more preferably 4.18 or less, particularly preferably 2.30 or less, and most preferably 0.90 or less.

From the above-mentioned preferred aspects, the upper limit and the lower limit are appropriately selected to satisfy the following formula (2a).

上述(2a)式中，Bi及Pb表示各合金組成之含量(質量ppm)。

In the above formula (2a), Bi and Pb represent the content (mass ppm) of each alloy composition.

The solder alloy of the second embodiment preferably satisfies the following formula (3).

上述(3)式中，As、Sb、Bi及Pb表示各合金組成之含量(質量ppm)。

In the above formula (3), As, Sb, Bi, and Pb represent the content (mass ppm) of each alloy composition.

As, Sb, Bi, and Pb are all elements that exhibit viscosity-increasing inhibitory effects. The total of these must be 275 mass ppm or more. In the formula (3), the As content is doubled because As has a higher viscosity-increasing inhibitory effect than Sb, Bi, or Pb.

(1) When the formula does not reach 275, the viscosity increase suppression effect cannot be fully exerted. (1) The lower limit of the formula is 275 or more, preferably 350 or more, and more preferably 1200 or more. On the other hand, the upper limit of (1) is not particularly limited in terms of the effect of thickening suppression, but from the viewpoint of keeping ΔT in an appropriate range, it is preferably 25200 or less, more preferably 10200 or less, and still more preferably 5300 or less , Particularly preferably below 3800.

From the above-mentioned preferred aspects, the upper and lower limits are appropriately selected to satisfy the following (3a) and (3b) formulas.

上述(3a)式及(3b)式中，As、Sb、Bi及Pb表示各合金組成之含量(質量ppm)。

In the above equations (3a) and (3b), As, Sb, Bi, and Pb represent the content (mass ppm) of each alloy composition.

The solder alloy of the second embodiment preferably satisfies the following formula (4).

[上述(2)式中，As、Sb、Bi及Pb表示各合金組成之含量(質量ppm)]。

[In the above formula (2), As, Sb, Bi, and Pb represent the content (mass ppm) of each alloy composition].

When the content of As and Sb is too much, the wettability of the solder alloy deteriorates. On the other hand, Bi and Pb can suppress the deterioration of wettability due to the inclusion of As, but if the content is too large, ΔT will increase, so strict management is required. Especially in an alloy composition containing both Bi and Pb, ΔT tends to increase. In view of this, if the content of Bi and Pb is increased and the wettability is excessively increased, ΔT will be widened. On the other hand, when the content of As or Sb is increased to increase the effect of suppressing viscosity increase, the wettability will be deteriorated. Therefore, in the second embodiment, when the two groups are divided into the group of As and Sb and the group of Bi and Pb, and the total amount of the two groups is within an appropriate specific range, all of the viscosity increase suppression effect and ΔT can be satisfied at the same time. The narrowing and wettability.

(4) When the formula does not reach 0.01, the total content of Bi and Pb is relatively higher than the total content of As and Pb, so ΔT will be wider. (4) The lower limit of the formula is 0.01 or more, preferably 0.02 or more, more preferably 0.41 or more, still more preferably 0.90 or more, particularly preferably 1.00 or more, and most preferably 1.40 or more. On the other hand, when the formula (4) exceeds 10.00, the total content of As and Pb is relatively larger than the total content of Bi and Pb, and therefore the wettability is deteriorated. The upper limit of (4) is 10.00 or less, preferably 5.33 or less, more preferably 4.50 or less, still more preferably 2.67 or less, still more preferably 4.18 or less, particularly preferably 2.30 or more.

In addition, the denominator of the formula (4) is "Bi+Pb". If these are not included, the formula (4) does not hold. That is, the solder alloy of the second embodiment must contain at least one of Bi and Pb. The alloy composition without Bi and Pb, as mentioned above, has poor wettability. The upper limit and the lower limit are appropriately selected from the above-mentioned preferred aspects to satisfy the following formula (4a).

上述(4a)式中，As、Sb、Bi及Pb表示各合金組成之含量(質量ppm)。

In the above formula (4a), As, Sb, Bi, and Pb represent the content (mass ppm) of each alloy composition.

_{Ag is an arbitrary element that forms Ag 3} Sn at the crystal interface to improve the reliability and mechanical strength of the solder alloy. In addition, Ag-based ionization tends to be a relatively expensive element relative to Sn, and coexistence with As, Pb, and Bi promotes these viscosity-increasing inhibitory effects. The Ag content is preferably 0 to 4%, more preferably 0.5 to 3.5%, and still more preferably 1.0 to 3.0%.

Cu is an arbitrary element that can improve the bonding strength of solder joints. In addition, Cu-based ionization tends to be a relatively expensive element with respect to Sn, and coexistence with As, Pb, and Bi contributes to these thickening suppression effects. The Cu content is preferably 0 to 0.9%, more preferably 0.1 to 0.8%, and still more preferably 0.2 to 0.7%.

The remaining part of the solder alloy of this embodiment is Sn. In addition to the aforementioned elements, unavoidable impurities may also be contained. Containing unavoidable impurities does not affect the aforementioned effects. In addition, as described later, even if an element that is not contained is contained as an inevitable impurity in this embodiment, it has no influence on the aforementioned effect. If the content of In is too large, ΔT becomes wider, so if it is 1000 ppm by mass or less, there is no influence on the aforementioned effect.

The content of the solder alloy and flux in the solder paste is not limited, and may be, for example, 5-95% by weight of the solder alloy and 5-95% by weight of the flux.

The solder paste of this embodiment preferably contains zirconia powder. Zirconia can suppress the increase in the viscosity of the paste that changes with time. This is presumably because the oxide film thickness on the surface of the solder powder is maintained at the state before it is put into the flux by containing zirconia. The details are not clear, but it is speculated as follows. Generally, in order to make the active components of the flux active even at room temperature, the surface oxide film of the solder powder is reduced by reduction, which causes the powders to agglomerate with each other. Therefore, it is speculated that by adding zirconia powder to the solder paste, the active components of the flux preferentially react with the zirconia powder, and the oxide film on the surface of the solder powder is maintained to a degree that does not agglomerate.

In order to give full play to these effects, the content of zirconia powder in the solder paste is preferably 0.05 to 20.0% relative to the total mass of the solder paste. If it is 0.05% or more, the above-mentioned effect can be exerted, and if it is 20.0% or less, the content of the metal powder can be ensured, and the effect of preventing thickening can be exerted. The content of zirconia is preferably 0.05 to 10.0%, more preferably 0.1 to 3%.

The particle size of the zirconia powder in the solder paste is preferably 5 μm or less. If the particle size is 5μm or less, the printability of the paste can be maintained. The lower limit is not particularly limited, but it may be 0.5 μm or more. The above-mentioned particle size is taken by taking the SEM photograph of the zirconia powder. For each powder of 0.1 μm or more, the diameter of the projection equivalent circle is obtained by image analysis, and the average value is taken.

The shape of zirconia is not particularly limited. If it is an irregular shape, the contact area with the flux is large, and it has a viscosity-increasing suppression effect. If it is spherical, good fluidity is obtained, so excellent printability as a paste is obtained. It is sufficient to select an appropriate shape corresponding to the desired characteristics. [Example]

The following examples and comparative examples are used to describe the present invention in more detail, but the technical scope of the present invention is not limited thereto.

The fluxes of Examples A1 to 45 and Comparative Examples A1 to 3 were blended with the compositions shown in Tables 1 to 6 below, and the solder paste was blended with the flux to verify the wetting speed of the flux. In addition, the composition ratio in the following table is wt (mass)% when the total amount of flux is set to 100.

The solder paste system flux is 11wt%, and the metal powder is 89wt%. In addition, the metal powder in the solder paste is Ag 3.0wt%, Cu is 0.5wt%, and the rest is Sn Sn-Ag-Cu solder alloy. The average particle size of the metal powder is ϕ20μm.

＜Review of Flux＞ (1) Evaluation of solder wettability (wetting speed) (Authentication method) The wetting speed of the solder paste is based on the crescent test method. A copper plate with a width of 5 mm × a length of 25 mm × a thickness of 0.5 mm is oxidized at 150°C for 1 hour to obtain a copper oxide plate of the test board. Use a solder checker (Solder Checker) SAT-5200 (manufactured by RHESCA) was used as a test device and Sn-3Ag-0.5Cu (each value is wt%) as a solder, and the evaluation was performed as follows. First, for each flux of the Examples and Comparative Examples measured from a beaker, the test plate was immersed by 5 mm, and the test plate was coated with the flux. Then, after the flux is applied, the test board coated with the flux is quickly immersed in the solder tank to obtain the zero crossing time (sec). Next, the measurement was performed 5 times for each flux of the example and the comparative example, and the average value of the obtained 5 zero-point crossing times (sec) was calculated. The test conditions are set as follows. Dipping speed in solder tank: 5mm/sec (JIS Z 3198-4:2003) Dipping depth in solder tank: 2mm (JIS Z 3198-4:2003) Dipping time in solder tank: 10sec (JIS Z 3198-4:2003) Solder tank temperature: 245℃ (JIS C 60068-2-69:2019) The shorter the average value of the zero crossing time (sec), the higher the wetting speed and the better the solder wettability.

(Judgment criteria) ○: The average value of the zero crossing time (sec) is 6 seconds or less. ×: The average value of the zero crossing time (sec) exceeds 6 seconds.

(2) Evaluation of Residue Fracture Inhibition Use a 0.15mm thick metal mask to print the paste on a substrate with electrode pads of size 1.5×0.25mm arranged in 64 rows at a pitch of 0.4mm, and use a reflow furnace for soldering (the peak temperature of reflow is 240℃). After reflowing, place it in a room temperature environment for more than 24 hours, calculate the number of cracks in the flux residue existing between the solder pads, and evaluate it based on the following. ○: There are 15 or less residue cracks. ×: More than 15 residues are broken.

In addition, the maleic acid-modified rosin ester and the maleic acid-modified rosin amide compound in the table all include their isomers (structural isomers, stereoisomers).

The flux of this embodiment contains a hydrogenated product selected from the group consisting of maleic acid-modified rosin ester, maleic acid-modified rosin amide, the aforementioned maleic acid-modified rosin ester, and the aforementioned maleic acid-modified rosin amide It is one or more of the group of things, and it suppresses the cracking of the residue of the flux residue and has excellent solder wettability.

＜Review of solder alloy＞ The flux prepared in Example A1 is composed of the alloy composition shown in Table 7~Table 18, and meets the size (particle size) in the classification of powder size in JIS Z 3284-1:2014 (Table 2) Distribution) of the solder alloy is mixed to make a solder paste. The mass ratio of flux to solder alloy is flux: solder powder = 11:89. For each solder paste, the change in viscosity over time was measured. In addition, the liquidus temperature and solidus temperature of the solder powder are measured. In addition, the wettability evaluation was performed using the solder paste immediately after production. The details are as follows.

(3) Changes over time For the solder paste just after production, PCU-205 manufactured by MALCOM Co., Ltd. was used, and the viscosity was measured for 12 hours at a rotation speed of 10 rpm, 25° C., and the atmosphere. When the viscosity after 12 hours is compared with the viscosity after 30 minutes after the solder is made, if it is 1.2 times or less, it is regarded as the one that has a sufficient viscosity increase suppression effect and evaluated as "○", and if it exceeds 1.2 times, it is evaluated as "× ".

(4) ΔT For the solder alloy before mixing with the flux, use SII Nanotechnology Co., Ltd. model: EXSTAR DSC7020, sample size: about 30mg, heating rate: 15℃/min for DSC measurement to obtain solidus temperature and liquidus temperature . ΔT is obtained by subtracting the solidus temperature from the obtained liquidus temperature. When ΔT is 10°C or less, it is evaluated as "○", and when it exceeds 10°C, it is evaluated as "×".

(5) Wetability: Print each solder paste just after fabrication on a Cu board, heat it from 25°C to 260°C at a temperature increase rate of 1°C/s _{in a reflow furnace in a N 2 environment, and then cool it to the room} temperature. Observe the appearance of the solder bumps after cooling with an optical microscope to evaluate the wettability. When no unmelted solder powder was observed, it was evaluated as "○", and when unmelted solder powder was observed, it was evaluated as "×".

(6) Comprehensive evaluation ○: All the above evaluations are ○ ×: In the above evaluations, there is ×

As shown in Tables 7-18, the results of the evaluation of the solder paste containing the flux of Example A1 and the solder alloy of Example B, all of Example B (Examples B2~B95; and Example B2-1~implementation In Examples B2~108), good results were obtained for any of the thickening inhibitory effect, ΔT, and wettability.

In contrast, Comparative Examples B1, B10, B19, B28, B37, and B46 do not contain As, and therefore cannot exhibit the effect of suppressing the increase in viscosity.

In Comparative Examples B2, B11, B20, B29, B38, and B47, since the formula (1) did not reach the lower limit, they could not exert the effect of suppressing viscosity increase.

In Comparative Examples B3, B4, B12, B13 , B21, B22, B30, B31, B39, B40, B48, and B49, the As content exceeds the upper limit, and therefore the wettability is poor.

Comparative examples B5, B7, B9, B14 , B16, B18, B23, B25, B27, B32, B34, B36, B41, B43, B45, B50, B52 and B54 due to the Pb content and the formula (2) exceeding the upper limit, Therefore, it shows the result that ΔT exceeds 10°C.

Comparative examples B6, B15 , B24, B33, B42, and B51 exceeded the upper limit of the formula (2), and therefore showed a result that ΔT exceeded 10°C.

In Comparative Examples B8, B17 , B26, B35, B44, and B53, the Bi content and the formula (2) exceeded the upper limit, so the results showed that ΔT exceeded 10°C.

Since Comparative Examples B2-1, B2-14 , B2-27, B2-40, B2-53, and B2-66 do not contain As, they cannot exhibit the effect of suppressing viscosity increase.

In Comparative Examples B2-2, B2-15 , B2-28, B2-41, B2-54, and B2-67, since the formula (3) does not reach the lower limit, the viscosity increase suppression effect cannot be exerted.

Comparative Examples B2-3, B2-16 , B2-29, B2-42, B2-55, and B2-68 have poor wettability because the formula (4) exceeds the upper limit.

Comparative examples B2-4, B2-5, B2-17 , B2-18 , B2-30, B2-31, B2-43, B2-44, B2-56, B2-57, B2-69 and B2-70 due to As content and formula (4) exceed the upper limit, it shows poor wettability.

Comparative example B2-6~B2-8; B2-19~B2-21; B2-32~B2-34; B2-45~B2-47; B2-58~B2-60; and B2-71~B2-73 Since the Sb content exceeds the upper limit, the wettability is poor.

Comparative examples B2-9, B2-10 , B2-22, B2-23, B2-35, B2-36, B2-48, B2-49, B2-61, B2-62, B2-74 and B2-75 The Bi content exceeds the upper limit, so it shows the result that ΔT exceeds 10°C.

Comparative examples B2-11, B2-13 , B2-24, B2-26, B2-37, B2-39, B2-50, B2-52, B2-63, B2-65, B2-76 and B2-78 The Pb content exceeds the upper limit, so it shows the result that ΔT exceeds 10°C.

Comparative Examples B2-12, B2-25 , B2-38, B2-51, B2-64, and B2-77 do not contain Bi and Pb, and the formula (4) does not hold, so the wettability is poor.

＜Combination of flux and solder alloy＞

Instead of the flux of embodiment A1, and use various fluxes of embodiment A2~A45, respectively, combine the various solders of embodiment B (embodiment B2-B95; and example B2-1~embodiment B2-108) In the case of the alloy, the results of the viscosity increasing inhibition effect, ΔT and wettability are good.

＜Preparation of flux composition for reflow soldering＞ Use the composition shown in Tables 13 to 15 below to blend the flux composition for reflow soldering of Reference Examples C1 to C36.

Even when the flux of the present embodiment is used as a flux for flow soldering, it is possible to suppress the cracking of the residue of the flux residue, and the solder wettability is also excellent.

This application is based on the Japanese patent application number (Japanese Patent Application No. 2019-098775) filed on May 27, 2019, the Japanese patent application number (Japanese Patent Application No. 2019-098782) filed on May 27, 2019, and May 26, 2020. Japanese Patent Application No. (Japanese Patent Application No. 2020-091559) filed on May 26, 2019 and Japanese Patent Application No. (Japanese Patent Application No. 2020-091571) filed on May 26, 2019, the contents of which are incorporated herein by reference.

Claims (9)

A composition for soldering flux, which contains selected from the group consisting of maleic acid-modified rosin ester, maleic acid-modified rosin amide, the aforementioned maleic acid-modified rosin ester hydride, and the aforementioned maleic acid-modified rosin amide One or more of the group of hydrides. The composition for flux according to claim 1, wherein the aforementioned maleic acid-modified rosin ester or maleic acid-modified rosin amide is selected from the group of compounds represented by the following formulas (1) to (7) Of more than one,

(In the formula, R each independently represents a substituted linear or branched alkyl group, an alkanediol group or a terminal modified polyalkoxyl group, and R'each independently represents a substituted linear or branched alkylene group Group or divalent alkylene glycol group). A flux for soldering solder alloys, which contains the flux composition of claim 1 or 2. Such as the flux of claim 3, wherein the content of the aforementioned maleic acid-modified rosin ester and/or maleic acid-modified rosin amide is more than 0wt% and less than 60wt% with respect to the total flux. Such as the flux of claim 3 or 4, wherein the aforementioned flux further contains a thixotropic agent. Such as the flux of any one of claims 3 to 5, wherein the aforementioned flux further comprises 0wt% above 20wt% of amine, 0wt% above 5wt% of organic halogen compounds, 0wt% above 2wt% amino hydrohalide, or 0wt% above 5wt% antioxidant, 0wt% above 80wt% resin. A solder paste comprising the flux and solder alloy according to any one of claims 3 to 6. Such as the solder paste of claim 7, wherein the aforementioned solder alloy has the following alloy composition: As: 25~300 mass ppm, Bi: 0 mass ppm or more and 25,000 mass ppm or less, Pb: more than 0 mass ppm and 8000 mass ppm or less, The rest is composed of Sn, and satisfies the following (1) and (2):

[In the above formulas (1) and (2), As, Bi, and Pb represent the contents (mass ppm) of the aforementioned alloy compositions]. Such as the solder paste of claim 7, wherein the aforementioned solder alloy has the following alloy composition: As: 25~300 mass ppm, Pb: more than 0 mass ppm and 5100 mass ppm or less, Sb: more than 0 mass ppm and 3000 mass ppm or less , And Bi: at least one of more than 0 mass ppm and less than 10,000 mass ppm, the rest: made of Sn, and satisfying the following (3) and (4):

[In the above equations (3) and (4), As, Sb, Bi, and Pb represent the contents (mass ppm) of the aforementioned alloy compositions].