JPS60145298A - Flux for hardly solderable base metal - Google Patents

Abstract

PURPOSE:To improve solderability by using an org. amine hydrofluoric acid salt as an activator for a flux and adding further a hydrobromate acid salt of an org. amine, etc. thereto. CONSTITUTION:If an adequate amt. of cyclohexyl amine is used as an additive with WW rosin as a base material for a flux, the flux exhibits good solderability with a stainless steel, aluminum coated steel and chromate treated steel, etc. If hydrobromate acid salt or hydrochloric acid salt of an org. amine is further added to the activator of the org. amine hydrofluoric acid salt, the base material and activator melt with each other, thus eliminating the uneven presence of the org. amine hydrochloric acid salt. Hardly solderable base metals are satisfactorily soldered by the above-mentioned method and the corrosiveness of the residue is eliminated as well.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flux 7 for use in difficult-to-solder base materials such as stainless steel, aluminum-plated steel, and chromate-treated steel.

Part materials used in recent electronic industries and communication equipment include:
Stainless steel, aluminum-plated or chromate-treated steel, etc. are used because weather resistance and corrosion resistance are important, but since the surface of these materials is covered with a strong oxide film, it is difficult to use conventional methods. This makes soldering difficult.

For such difficult soldering, it is necessary to solder the base material.
As is well known, soldering has generally been carried out using a strong acid flux containing a strong acid such as phosphoric acid or hydrofluoric acid as a main ingredient, or a water-soluble flux containing a chloride of these acids as a main ingredient.

However, since these flux residues are corrosive, they require post-treatment such as washing with water. Naturally, this requires a great deal of cost to add waste liquid treatment facilities after washing, and it is impossible to wash with water. However, it has disadvantages such as being unsuitable for electronic equipment parts.

For this reason, there is a strong demand for the development of non-corrosive fluxes for base metals that are difficult to solder such as stainless steel, aluminum plated or chromate-treated steel, and several types of resin-based fluxes are already known. However, such resin-based fluxes have not necessarily been able to fully satisfy the above requirements. In other words, the conditions required for resin-based fluxes are: firstly, the activator of the flux must be easily compatible with the resin, secondly, soldering can be carried out satisfactorily, and thirdly, there must be no residue. It is non-corrosive, and fourthly, it is easy to manufacture. However, in the conventional resin-based flux, it is not possible to ensure compatibility or miscibility of the flux activator with the rosin as a flux base component, and the flux activator is extremely unevenly distributed in the rosin. When it is soldered manually, it may be possible to solder in some places, but it may be difficult to solder in other places, or the soldering may cause corrosion in the residue after soldering. However, the quality was not necessarily satisfactory. The main reason for this is that the flux activator is not completely dissolved in the rosin, which is the flux base.

For this reason, the present inventors conducted various experiments in order to obtain a stable flux activator that is compatible with a flux base such as rosin. It has been found that when soldering is performed with a hydrofluoride salt present, the oxide film on the surface of the base material can be removed extremely quickly and good soldering can be achieved.

Moreover, this organic amine hydrofluoride is easily compatible with WW rosin by heating and melting it and adding it to WW rosin, and does not precipitate even after cooling and solidifying the rosin, and its appearance is It was found that it exhibits a stable brown-transparent state, which led to the provision of the present invention.

Therefore, according to the present invention, by producing a soldering flux using an organic amine hydrofluoride such as cyclohexylamine hydrofluoride or isopropylamine hydrofluoride as an activator, stainless steel,
For difficult-to-solder materials such as aluminum-plated steel, it is possible to easily solder to the base material, and the residue is not corrosive, and the manufacturing method is easy. It is possible.

The present invention will be explained in detail below.

[Example 1] Cyclohexylamine hydrofluoride (as an activator) was added to 95% by weight of WW rosin as a flux base.
A flux for a base material that is difficult to solder was manufactured by adding 5% by weight of CHA HF). According to this Example 1, as shown in Table 1, stainless steel and aluminum-plated steel can be soldered normally, but chromate-treated steel can be soldered with organic amine-based oxides on the surface. It cannot be removed with hydrofluoride and cannot be soldered.

In this Example 1, the soldering properties of stainless steel, aluminum plated steel, and chromate-treated steel are shown in Table 2 below when the ratio of cyclohexylamine hydrofluoride to WW rosin was varied.

Here, the symbol x indicates that soldering is impossible, the symbol Δ indicates that soldering is possible, and the symbol O indicates that soldering is good. As is clear from Table 2, it is understood that by increasing the amount of cyclohexylamine hydrofluoride added to the rosin, it becomes possible to solder even chromate-treated steel.

[Example 2] Isopropylamine hydrofluoride (I) as an activator was added to 95% by weight of WW rosin as a flux base.
A flux for base material for wax soldering was manufactured by adding 5% by weight of PA 1(F). According to this Example 2, as shown in Table 1, it was possible to obtain exactly the same soldering properties as in Example 1.

[Example 3] To 95% by weight of WW rosin as a flux base, 4% by weight of cyclohexylamine hydrofluoride as an activator and 1% by weight of monoethanolamine (MEA) were added to make it difficult to solder. At the same time, we manufactured flux for use.

According to this Example 3, as shown in Table 1, relatively good soldering could be performed on stainless steel, aluminum-plated steel, and chromate-treated steel fittings.

In addition, in Example 3, when the ratio of cyclohexylamine hydrofluoride (CHAHF) and monoethanolamine (MEA) to WW rosin was changed, the results of stainless steel, aluminum-plated steel, and chromate-treated steel were The soldering properties and rosin conditions are shown in Table 3 below.

Here, the symbol ○ indicates that the soldering is good, and the symbol ◎ indicates that the soldering is extremely good. As is clear from these examples, by increasing the amount of cyclohexylamine hydrofluoride and further adding monoethanolamine (MRA),
Soldering with flux can further improve the effect.

[Example 4] A flux for difficult soldering was produced by adding 4% by weight of cyclohexylamine hydrofluoride and 2% by weight of jetanolamine to 94% by weight of WW rosin as a flux base. did. According to this Example 4, as shown in Table 1, exactly the same soldering properties as in Example 3 could be obtained.

[Example 5] A flux for difficult soldering was produced by adding 4% by weight of cyclohexylamine hydrofluoride and 5% by weight of monoethanolamine to 91% by weight of WW rosin as a flux base. . According to this Example 5, as shown in Table 1, extremely good soldering could be performed on all stainless steel, aluminum plated steel, and chromate treated steel.

[Example 6] 4% by weight of cyclohexylamine hydrofluoride was added to 90% by weight of WW rosin as a flux base. A difficult-to-solder flux was prepared by adding 2% by weight of monoethanolamine and 4% by weight of triethylamine hydrobromide (TEA Her).

This example? According to Table 1, very good soldering was possible for all stainless steel, aluminum plated steel, and chromate-treated steel. In this case, organic amine hydrofluoride salts have a low decomposition point, so depending on the temperature, the solder may not continue to spread during soldering. Therefore, by adding organic amine hydrochloride or hydrobromide as in this example, the synergistic effect of these additives and hydrofluoride makes it difficult to solder the base material. The attachment can be done in the best condition.

[Example 7] 63% by weight of WW rosin as flux base.

To this, 27% by weight of modified rosin, 4% by weight of cyclohexylamine hydrofluoride, 2% by weight of monoethanolamine, and 4% by weight of triethylamine hydrobromide were added to make Franks for difficult soldering. Manufactured. According to this Example 7, as in Example 6, extremely good soldering to the base material could be performed even though it was difficult to solder.

In this case, a difficult-to-solder flux manufactured by combining an organic amine hydrofluoride such as cyclohexylamine or isopropylamine with an alkanolamine is
For difficult soldering, the solder exhibits good "wettability" to the base material, but since alkanolamine is a liquid, increasing its weight percentage softens the properties of the flux used for difficult soldering. Although this will reduce the coating performance on the base material to be soldered, as in this example, by adding a modified rosin with a higher softening point than WW rosin, it is possible to obtain a flux for chick soldering with appropriate hardness. can.

[Example 8] As a flux base, 5 g of cyclohexylamine hydrofluoride and 5 g of monoethanolamine were added to an organic solvent in which 25 g of ethyl cellosolve and 25 g of calpitol were dissolved, and a flux for the base material was used for difficult soldering. Manufactured. According to this example, similar to Example 3 when WW rosin was used as the flux base, each difficult-to-solder case had extremely good soldering properties to the base material. In this case, the flux has water-insoluble properties. Further, since ethyl cellosolve has a low boiling point, it cannot be used alone as a flux base, whereas carbitol has a high boiling point, so it can be used alone as a flux base. In addition, organic solvents such as isopropyl alcohol can be used as the flux base.

[Example 9] 5 g of cyclohexylamine hydrofluoride and 5 g of monoethanolamine were added to a water-soluble solvent in which 25 g of glycerin and 25 g of polyethylene glycol were mixed as a flux base, and these were mixed to make it difficult to solder. manufactured flux for base metal. According to this example, as in Example 8, the soldering properties of each difficult-to-solder material to the base material were extremely good.

In each example, the residual liquid after soldering exhibits non-corrosive properties.

l soil Here, the symbol × means that soldering is not possible. Symbol ○ indicates good soldering. Symbol ◎ indicates extremely good soldering. are shown respectively.

As explained above, according to the present invention, female soldering can be performed using organic amine fluoride/hydrochloride such as cyclohexylamine hydrofluoride or propylamine hydrofluoride as an activator. Since the flux is obtained, the flux base such as rosin and the activator made of organic amine hydrofluoride are compatible with each other, and the organic amine hydrofluoride is not unevenly distributed. Difficult-to-solder materials such as aluminum plated steel, chromate-treated steel, etc. can be soldered well to the base metal, and the residue after soldering does not have corrosive properties, and it is easy to manufacture. Difficult soldering has the effect of being able to obtain a base metal flux that satisfies all the requirements for a flux for use in difficult soldering.

Claims (1)

[Claims] (11) As an activator in a flux for difficult-to-solder base materials such as stainless steel, aluminum-plated steel, and chromate-treated steel,
A flux for base materials that is difficult to solder and is characterized by the use of organic amine hydrofluorides such as isopropylamine hydrofluoride and cyclohexylamine hydrofluoride. (2) Difficult-soldering according to claim 11, which is obtained by adding one or more of monoethanolamine, jetanolamine, and triethanolamine to the flux according to claim 111 and making them compatible with each other. is a flux for the base material. (3) The flux described in paragraph (1) or (2),
Claim No. 11 or (2) wherein one or more hydrochlorides or hydrobromides of organic amines such as ethylamine, isopropylamine, and cyclohexylamine are added and dissolved. Difficult soldering described in ) is for base metal flux.