JPH0890276A - Wire solder - Google Patents

Abstract

PURPOSE: To prevent the adhesion of the powder of solder to the hands and clothing by adhering a film on the outer periphery of wire solder. CONSTITUTION: This wire solder 10 having a round shape in section is formed by arranging a flux 2 at its center and arranging solder 1 which is an alloy of tin (Sn) and lead (Pb) so as to enclose the circumference thereof. A film 3 is adhered to the surface of the solder 1 so as to cover the solder. The wire solder 10 has the fluxes 2 formed as three cores in the solder 1 and the wire solder 10 has the flux 2 as a centric core in the solder and is adhered with the film 3 so as to cover the surface of the solder 1. The film 3 is formed of rosin-, org. acid- and inorg. acid based fluxes, their compds. or harmless metals, such as silver. Then, the absorption of the lead included in the solder 1 into the human body from the skin or the oral thereof into the body are prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thread solder used for manual soldering.

[0002]

2. Description of the Related Art In recent years, automation of flow soldering, reflow soldering, etc., for soldering (wiring) of electric equipment has progressed. Soldering using thread solder is a small-scale production product or a design. It is generally performed by a person during a manual work for developing and prototyping a device.

Thread solder used for manual soldering is generally wound around a bobbin as shown in FIG. 3 (a). For example, the thread solder 10 has the same structure. It is supposed to be enlarged and shown in FIG. That is, the flux 2 is arranged at the center, and the solder 1 which is an alloy of tin (Sn) and lead (PB) is arranged so as to surround the flux 2. The flux removes oxides on the metal surface during soldering, prevents reoxidation of the metal surface, and enables good soldering.

FIG. 4 (a) is a sectional view of the thread solder 10 shown in FIG. 3 (b), which has a substantially circular shape. There are also 10.
The thread solder 10 shown in FIG. 4 (b) has a flux 2 of three cores inside the solder 1, and FIG. 4 (c) has a flux 2 of a century core inside the solder 1. In addition to the structure, the cross section is substantially circular. The thread solder 10 having such a structure has a resistance of 0.
An outer diameter of 3 to 3 mm is usually used. Also,
As the flux, an active flux obtained by adding an activator such as an organic amine to pine resin (rosin) or resin (resin) is generally used.

Next, a general work process of manual soldering using the above-described thread solder 10 will be described with reference to FIG. 1. As shown in FIG. 3A, hold the thread solder 10 and the soldering iron 11 by hand and check the soldering points on the component 12. 2. As shown in FIG. 3B, the tip of the iron is applied to the soldering point of the component 12 and uniformly heated. 3. As shown in FIG. 3C, the thread solder 10 is applied to the component side, and the thread solder 10 is melted by the soldering iron 11. 4. When a predetermined amount of the thread solder 10 is melted, the thread solder 10 is released as shown in FIG. 5. As shown in (e) of the figure, when the soldering iron 11 is released, the soldering of the soldering points of the component 12 is completed.

By the way, the thread solder 10 is designed to have a certain length so that it can be naturally sent out at the time of soldering. An example of this mode is shown in FIGS. 6 (a) and 6 (b).

[0007]

As described above, the solder, which is a lead alloy, is exposed on the surface of the thread solder, and when soldering by hand, as shown in FIG. In order to hold the alloy powder 10, the alloy powder adhering to the surface of the thread solder 10 is transferred to the hand. Also, since the solder is a very soft alloy, if it is rubbed on the surface, it is easily scraped off and adheres to hands and clothes. These lead alloys (solders) attached to hands and clothes are gradually absorbed from the surface of the skin, orally ingested by the body when eating, drinking or smoking. There was a fear of becoming.

Therefore, the Industrial Safety and Health Act establishes a lead poisoning prevention rule that regulates the working environment such as ventilation and hand washing. In addition, according to the survey material “Hazardous substances in the soldering workshop” of the Institute of Labor Sciences, as a result of investigating using solder containing solder (flux), “most of the smoke generated during soldering is flux. It is considered that the fumes of gas and rosin or resin produced by the thermal decomposition of the above are small in the amount of metal fumes even when judged from the heating conditions. In other words, lead poisoning caused by smoke generated by soldering work is small, and lead poisoning is mainly caused by absorption through the skin or oral intake such as eating and drinking or smoking.

However, the Industrial Safety and Health Law does not prevent the lead alloy solder from adhering to the hands or clothes during the soldering work by defining the working environment. As it prevents oral ingestion and absorption from the skin, it makes the hygiene management of the soldering site difficult and the hygiene management becomes complicated. There was a point.

Therefore, an object of the present invention is to provide a thread solder in which a lead alloy hardly adheres to a hand or clothes.

[0011]

In order to achieve the above object, the thread solder of the present invention comprises a flux and a solder which covers the flux, wherein a coating is attached to the outer periphery. Is.

Further, in the above-mentioned thread solder, the coating film is formed of a rosin-based flux, an organic acid-based flux, an inorganic acid-based flux, or a composite thereof.
Alternatively, the coating film is formed of a harmless metal such as silver.

[0013]

According to the present invention, since the coating is adhered to the surface of the flux-containing thread solder, the solder is not exposed except at the end surface thereof, and therefore even if the surface of the thread solder is touched during soldering work or the like. It is possible to prevent solder powder from adhering to hands and clothes. Therefore, it is possible to prevent lead poisoning,
The work environment can be reviewed.

[0014]

EXAMPLE A cross section of an example of the thread solder of the present invention is shown in FIG. In (a), (b) and (c) of this figure, 1 is solder which is an alloy of tin (Sn) and lead (PB), 2 is flux for good soldering, and 3 is on the surface of solder 1. It is an attached film. In the thread solder 10 having a substantially circular cross section shown in FIG. 1 (a), the flux 2 is arranged at the center,
Solder 1, which is an alloy of tin (Sn) and lead (PB), is arranged so as to surround it. The coating 3 is attached so as to cover the surface of the solder 1.

Further, the thread solder 10 having a substantially circular cross section shown in FIG. 1 (b) has a flux 2 of three cores inside the solder 1, and the coating 3 is attached so as to cover the surface of the solder 1. Has been done. Further, the thread solder 10 having a substantially circular cross section shown in FIG. 1C has a flux 2 that is a century core inside the solder 1, and a coating 3 is attached so as to cover the surface of the solder 1. . As described above, since the surface of the solder 1 is covered with the coating 3, even if the surface of the thread solder 10 is touched during the soldering work, the solder powder does not adhere to the hands or clothes, and thus the solder 1 It is possible to prevent the lead contained in the product from being absorbed through the skin and being orally taken into the body during eating, drinking and smoking.

As the material of the coating 3, a rosin-based flux, an organic acid-based flux, an inorganic acid-based flux, a composite of these, or the like can be used. Further, a harmless metal such as silver may be attached to the surface of the solder 1 by plating or another method.

By the way, in general, the flux 2 is contained in the thread solder 10 only at a maximum of about 3% by weight,
For this reason, the action of the flux is insufficient, and in order to compensate for this, there is a need for pretreatment such as solder plating or tin plating that tends to cause soldering. Therefore, if the above-mentioned flux is used as the coating 3, the coating 3
Since the total amount of flux is increased to 4 to 5% by weight by the above flux, it is possible to obtain an effect of facilitating soldering.

Here, FIG. 2 shows an example of an organic flux capable of forming the coating film 3 of the present invention. As shown in this figure, there are those based on rosin without addition of an activator, and those based on a resin which use an amine halogen salt, an organic acid, an amine organic acid salt or the like as an activator. The activator is a component having an action of dissolving and removing compounds such as molten solder and metal oxides present on the surface of the base material, and is also a kind of corrosive agent. Examples of the activator include organic salts, amines, amino acids, organic acid salts of amines, halogen salts of amines, inorganic acids and inorganic acid salts as described above. Also,
Polyester polycarboxylic acid can also be used as an activator of the flux forming the coating 3 of the present invention.

Further, when soldering parts having silver plated lead wires such as a crystal oscillator or a thermistor,
The coating 3 attached to the outer peripheral surface of the thread solder 10 is formed by plating silver or the like,
By using and soldering, it is possible to perform wiring with good electrical characteristics.

[0020]

As described above, according to the present invention, since the coating is adhered to the surface of the flux-cored thread solder, the solder is not exposed except at the end face thereof. Even if you touch, you can prevent the solder powder from sticking to your hands or clothes. Therefore, lead poisoning can be prevented and the work environment can be reviewed.

[Brief description of drawings]

FIG. 1 is a view showing a cross section of a thread solder according to an embodiment of the present invention.

FIG. 2 is a diagram showing an example of an organic flux.

FIG. 3 is a view showing a conventional thread solder.

FIG. 4 is a view showing a cross section of a conventional thread solder.

FIG. 5 is a diagram showing a work process of soldering.

FIG. 6 is a diagram showing how to hold the thread solder.

[Explanation of symbols]

 1 Solder 2 Flux 3 Coating 10 Thread Solder 11 Soldering Iron 12 Parts

Claims (3)

[Claims] 1. A thread solder consisting of a flux and a solder covering the flux, wherein a coating is attached to the outer periphery of the thread solder. 2. The thread solder according to claim 1, wherein the coating film is formed of a rosin-based, organic acid-based, inorganic acid-based flux, or a composite thereof. 3. The thread solder according to claim 1, wherein the coating film is formed of a harmless metal such as silver.