Linear solder and bundle-shaped solder

Abstract

To provide a linear solder which can shorten the processing time of soldering and in which dirt is hardly accumulated even when soldering processing is repeated.SOLUTION: The wire-shaped solder 1a has a wire-shaped body part 11 and three flux parts 12a, 12b, and 12c which are built in the body part 11 and continue in the axial direction of the body part 11, and the components of the flux part 12a are different from those of the flux parts 12b and 12c.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a solder wire and a solder bundle using the same. [Background technology]

[0002] The inventor of the present invention proposed a soldering device equipped with a heatable soldering iron tip and a roughly cylindrical solder hole penetrating the axial direction, in order to prevent flux scattering, to keep the amount of solder used in each soldering operation constant, and to perform good soldering (see, for example, Patent Document 1). In this soldering device, solder pieces cut from linear solder to a predetermined length are fed into the solder hole, where they are heated and melted to solder the part to be soldered. The linear solder used here typically has a linear body made of a solder alloy and a flux portion built into the body and continuing axially from the body.

[0003] Furthermore, the inventors proposed the use of linear solder in which the flux portion is positioned eccentrically from the central axis of the main body, with the aim of shortening the processing time when soldering using the soldering device proposed above (Patent Document 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. WO2008 / 023461 [Patent Document 2] Japanese Patent Publication No. 2023-26821 Summary of the Invention [Problem to be solved by the invention]

[0005] When soldering is repeated, some of the flux components may become contaminants and adhere to and accumulate on the inner wall of the solder hole of the soldering iron tip. If contaminants accumulate on the inner wall of the solder hole, the inner diameter of the solder hole may become smaller, preventing the molten solder from flowing down, which may result in poor soldering. become

[0006] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a linear solder that can shorten the soldering process time and that is less susceptible to the accumulation of dirt even after repeated soldering processes. [Means for solving the problem]

[0007] In order to achieve the above object, one embodiment of the linear solder of the present invention has a linear main body portion made of a solder alloy and two or more flux portions embedded in the main body portion and continuous in the axial direction of the main body portion, and is characterized in that the composition of at least one of the two or more flux portions is different from the composition of the other flux portions.

[0008] In the linear solder having the above configuration, it is preferable that at least one of the two or more flux portions has an acid value of 60 KOHmg / g or less. Note that, in this specification, the acid value of the flux is a value measured in accordance with JIS Z 3197:2012 8.1.4.1.1.

[0009] In the solder line having the above-described structure, the other flux portion preferably has an acid value of more than 60 KOHmg.

[0010] In the linear solder having the above configuration, it is preferable that the cross-sectional area of ​​at least one of the two or more flux portions is different from the cross-sectional area of ​​the other flux portions.

[0011] Furthermore, another aspect of the linear solder of the present invention is a bundled solder formed by bundling a plurality of linear solder pieces, characterized in that at least one of the plurality of linear solder pieces is any of the linear solder pieces described above.

[0012] Here, the solder line having the above configuration may be a bundle of a plurality of solder lines twisted together.

[0013] In the solder line having the above configuration, at least one of the plurality of solder lines may have an outer diameter different from that of the other solder lines. [Effects of the Invention]

[0014] The wire solder of the present invention can shorten the soldering process time and is less likely to accumulate dirt even when the soldering process is repeated. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a cross-sectional perspective view showing an embodiment of a linear solder according to the present invention. [Figure 2] 2 is a cross-sectional perspective view showing a modified example of the linear solder of FIG. 1. FIG. [Figure 3] FIG. 10 is a cross-sectional perspective view showing another embodiment of the linear solder according to the present invention. [Figure 4] 1 is a cross-sectional perspective view showing an embodiment of a bundled solder according to the present invention; [Figure 5] FIG. 10 is a cross-sectional perspective view showing another embodiment of the bundled solder according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, embodiments of the linear solder according to the present invention will be described with reference to the drawings, but the present invention is not limited to these embodiments. Furthermore, in the following embodiments, the same or corresponding components will be designated by the same reference numerals, and their description may be omitted as appropriate.

[0017] (First embodiment) Fig. 1 shows a cross-sectional perspective view of one embodiment of a linear solder according to the present invention. The linear solder 1a shown in Fig. 1 has a linear main body 11 made of a solder alloy and having a circular cross section, and three flux portions 12a to 12c, each having a circular cross section, built into the main body 11 and continuing in the axial direction of the main body 11. The first flux portion 12a and the second flux portions 12b and 12c differ in acid value, which is one of the components of the flux portions. Each portion will be described below.

[0018] (Main body 11) The main body 11 of the solder wire 1a is made of a solder alloy. There are no particular limitations on the solder alloy, and any conventionally known alloy can be used. Examples include Sn-Pb alloys, Pb-Sn-Sb alloys, Sn-Sb alloys, Sn-Pb-Bi alloys, Sn-Ag alloys, Sn-Sb alloys, Sn-In alloys, Sn-Bi alloys, Sn-Ge alloys, Sn-Zn alloys, Sn-Cu alloys, Sn-Ni alloys, In-Ag alloys, and Sn-Ag-Sb alloys. Among these, lead-free solder, which contains substantially no lead, is preferable. Lead-free solder refers to solder containing 0.1% by mass or less of Pb (lead).

[0019] (First flux portion 12a) The first flux portion 12a preferably has an acid value of 60 KOHmg or less. Having an acid value of 60 KOHmg / g or less reduces the accumulation of flux residue on the soldering tip and other surfaces. While the mechanism of contamination during soldering is not yet clear, it is presumed that the carboxyl groups in the rosin compound and the carboxyl groups in the organic acid activator contained in the flux become residue after soldering, imparting adhesion and promoting the accumulation of flux residue. Therefore, it is believed that reducing the acid value of the flux portion reduces the accumulation of contamination. The acid value of the first flux portion 12a is more preferably 20 KOHmg or less. The acid value of the flux portion can be controlled, for example, by adjusting the acid value and composition of rosin, one of the components of the flux. The acid value of rosin can be adjusted by esterifying the carboxyl groups of the rosin.

[0020] The first flux portion 12a is mainly composed of one or more types of rosin or its derivatives, and contains an amine organic acid salt, an amine halogen salt, or a halide as an activator, and other additives such as an antioxidant can also be added.

[0021] Examples of rosins include wood rosin, gum rosin, tall rosin, disproportionated rosin, hydrogenated rosin, fully hydrogenated rosin, maleic acid modified rosin, and rosin ester.

[0022] Examples of amines include primary amines such as ethylamine, cyclohexylamine, and benzylamine, secondary amines such as diethylamine, diethanolamine, and diphenylamine, and tertiary amines such as triethylamine, triethanolamine, and triisopropanolamine. These can be used alone or as their organic acid salts or hydrohalide salts. Other amines include quaternary amines such as tetraethylammonium salts, diphenylguanidine, and diphenylurea.

[0023] Examples of the organic acid include diglycolic acid, adipic acid, glutaric acid, dodecanedioic acid, propionic acid, succinic acid, and maleic acid.

[0024] Examples of the halides include 2,3-dibromopropanol, 1,3-dibromopropanol, 2,2,2-tribromoethanol, tribromomethylphenyl sulfone, trans-2,3-dibromobutenediol, pentaerythritol tribromide, tris(2,3-dibromopropyl) isocyanurate, and 2,2-bis[3,5-dibromo-4-(2,3-dibromopropoxy)phenyl]propane.

[0025] Furthermore, waxes such as polyethylene wax and ester wax can be added to these flux compositions.

[0026] The content of the activator in the first flux portion 12a is preferably 10% by mass or less. When the content of the activator is 10% by mass or less, insulation reliability is further improved. From the viewpoint of further improving insulation reliability, the content of the activator in the first flux portion 12a is more preferably 4% by mass or less, and even more preferably 3.5% by mass or less. Note that, from the viewpoint of ensuring wettability, the lower limit of the content of the activator in the first flux portion 12a is preferably 1% by mass, and more preferably 1.5% by mass.

[0027] (Second flux parts 12b, 12c) The second flux parts 12b and 12c preferably have an acid value of more than 60 KOHmg. When the second flux parts 12b and 12c have an acid value of more than 60 KOHmg, wettability is improved and good soldering can be easily performed. A more preferable acid value is 150 KOHmg or more.

[0028] Like the first flux part 12a, the second flux parts 12b and 12c are primarily composed of rosin or one or more of its derivatives, and contain an activator such as an amine organic acid salt, an amine halogen salt, or a halide, and may also contain other additives such as antioxidants. The rosin, activator, and additives that can be used in the second flux parts 12b and 12c are the same as those exemplified for the first flux part 12a.

[0029] To increase the acid value of the second flux portions 12b and 12c, rosin or a derivative thereof having a high (increased) acid value may be used. For example, the acid value of rosin or a derivative thereof may be increased by reacting rosin with an unsaturated acid such as an α,β-unsaturated acid.

[0030] The total content of the first flux portion 12a and the second flux portions 12b, 12c in the solder line 1a is not particularly limited, but is generally preferably in the range of 1% to 5% by mass relative to the solder line 1a. If the total content of the first flux portion 12a and the second flux portions 12b, 12c is less than 1% by mass, the effect of the flux may not be fully achieved, while if the content exceeds 5% by mass, the content of the solder alloy may be relatively low, which may result in poor soldering.

[0031] The total area ratio of the first flux portion 12a and the second flux portions 12b, 12c in a cross section perpendicular to the axial direction of the linear solder 1a is calculated appropriately from the total content of the first flux portion 12a and the second flux portions 12b, 12c in the linear solder 1a and the specific gravity of the flux and solder alloy, etc., but a range of 5% to 20% is usually preferable in a cross section perpendicular to the axial direction of the linear solder 1a.

[0032] There is no particular limitation on the diameter of the solder line 1a of the present invention, and it may be determined appropriately based on the shape and size of the object to be soldered, the inner diameter of the solder hole in the iron tip, etc., but generally, a diameter in the range of 0.6 mm to 5 mm is preferable.

[0033] The solder line 1a having such a configuration is manufactured by a conventionally known method, such as wire drawing, cold extrusion, or hot extrusion.

[0034] (Variation) FIG. 2 shows a modified example of the linear solder according to the first embodiment. In the linear solder 1a according to the first embodiment, the cross-sectional areas of the first flux portion 12a and the second flux portions 12b and 12c are the same in a cross section perpendicular to the axial direction of the linear solder 1a. However, in the linear solder 1b shown in FIG. 2, the cross-sectional area of ​​the first flux portion 12a is larger than the cross-sectional area of ​​the second flux portions 12b and 12c. In this way, the content of the first flux portion 12a and the second flux portions 12b and 12c in the linear solder 1b may be adjusted by increasing or decreasing the cross-sectional area of ​​the flux portions. Alternatively, the content of the first flux portion 12a and the second flux portions 12b and 12c in the linear solder 1b may be adjusted by increasing or decreasing the number of the first flux portion 12a or the second flux portions 12b and 12c.

[0035] (Second embodiment) Fig. 3 is a cross-sectional perspective view showing a second embodiment of the linear solder according to the present invention. Similar to the linear solder 1a according to the first embodiment, the linear solder 1c shown in Fig. 3 has a linear main body 11 made of a solder alloy and having a circular cross section, and three flux portions 12a, 12b, and 12d, each having a circular cross section and continuous in the axial direction of the main body 11, built into the main body 11. However, in the linear solder 1c shown in Fig. 3, unlike the linear solder 1a in Fig. 1, the three flux portions 12a, 12b, and 12d each have a different composition.

[0036] The first flux portion 12a and the second flux portion 12b are the same as those in the linear solder 1a of the first embodiment. The third flux portion 12d has a different composition from the first flux portion 12a and the second flux portion 12b. For example, the acid value of the third flux portion 12d is different from those of the first flux portion 12a and the second flux portion 12b. By differentiating the acid values ​​of the three flux portions 12a, 12b, and 12d, it becomes possible to more precisely control, for example, the resistance to flux residue accumulation and wettability. In this embodiment, the cross-sectional areas of the flux portions 12a, 12b, and 12d in a cross section perpendicular to the axial direction of the linear solder 1c may also be different.

[0037] (bundled solder) The solder bundle according to the present invention is a bundle of multiple solder lines, at least one of which is the solder line according to the present invention. By bundling multiple solder lines into a solder bundle, the time required to heat and melt the solder is shortened, improving the efficiency of the soldering work.

[0038] There are no particular limitations on the method of bundling multiple solder lines, and multiple solder lines may be twisted together, joined in parallel, etc. Among these, bundling by the twisting method is preferred because it does not require a bonding agent and the solder lines are difficult to separate.

[0039] Fig. 4 shows a perspective view of one embodiment of a bundled solder. The bundled solder 4 shown in Fig. 4 is formed by twisting together three linear solders 1a, 2, and 3. The linear solder 1a is the linear solder shown in Fig. 1 as the first embodiment. The linear solders 2 and 3 have linear main bodies 21 and 31 made of a solder alloy and single flux portions 22 and 32 that are continuous in the axial direction of the main bodies 21 and 31. Conventionally known linear solders can be used as the linear solders 2 and 3.

[0040] Fig. 5 is a perspective view showing another embodiment of a solder bundle. In the solder bundle 5 shown in Fig. 5, three solder lines 1a, 2, and 3 are joined in a substantially parallel state. The solder lines 1a, 2, and 3 are the same as those used in the solder bundle 4 shown in Fig. 4. The three solder lines 1a, 2, and 3 are preferably joined by applying a predetermined force from the outside to the inside so that the internal void surrounded by the solder lines 1a, 2, and 3 is small.

[0041] 4 and 5, one solder line 1a according to the present invention is used, but there is no limit to the number of solder lines 1a according to the present invention, and two or more may be used. Also, there is no particular limit to the number of solder lines constituting the solder bundle according to the present invention, as long as it is two or more.

[0042] (Other variations) Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments. Addition, omission, substitution, and other modifications of the configuration are possible within the scope of the spirit of the present invention. The present invention is not limited by the above description, but is limited only by the scope of the appended claims. [Industrial Applicability]

[0043] The wire solder according to the present invention is useful because it can shorten the soldering process time and is less likely to accumulate dirt even when the soldering process is repeated. [Explanation of symbols]

[0044] 1a, 1b, 1c Linear solder 2,3 Line solder 4,5 solder bundles 11, 21, 31 Main body 12a, 12b, 12c Flux section 22,32 Flux section

Claims

1. a linear body portion made of a solder alloy; two or more flux portions built into the main body portion and continuous in the axial direction of the main body portion, The composition of at least one of the two or more flux parts is different from the composition of the other flux parts. A linear solder characterized by:

2. 2. The solder line according to claim 1, wherein at least one of the two or more flux portions has an acid value of 60 KOHmg / g or less.

3. 3. The solder line according to claim 1, wherein the other flux portion has an acid value of more than 60 KOHmg.

4. At least one of the two or more flux portions has a cross-sectional area different from the cross-sectional areas of the other flux portions.

3. The solder line according to claim 1 or 2.

5. A bundled solder formed by bundling a plurality of solder wires, 3. A solder bundle, wherein at least one of the plurality of solder wires is the solder wire according to claim 1 or 2.

6. 6. The solder bundle according to claim 5, wherein a plurality of solder wires are twisted together and bundled.

7. 6. The solder bundle according to claim 5, wherein at least one of the plurality of solder wires has an outer diameter different from that of the other solder wires.

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