JP2003013262A - Stripping liquid for copper film plated on iron base-metal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stripping liquid for stripping a copper film plated on an iron base-metal, while controlling etching of the iron base-metal to an extremely low level. SOLUTION: The stripping liquid is characterized by being an alkaline solution which includes a copper (II) ammine complex having anions of highly corrosive acid to the iron base-metal as the counter ion, and an inhibitor. Then, the solution strips the copper film on the iron base-metal, and prevents the iron base-metal from corrosion due to the acid with the inhibitor.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a stripping solution for stripping copper plating formed on an iron substrate.

[0002]

2. Description of the Related Art For example, when carburizing to harden the surface of a part of an iron substrate, a carburizing-preventing mask is formed on the iron substrate that does not require carburizing, and the carburizing process ends. After that, the mask is peeled off.
Copper plating is often used as a carburizing prevention mask, and as one of the methods for removing the copper plating after carburizing treatment,
There is a stripping treatment using a stripping solution such as ammonium persulfate and ammonium dichromate.

[0003]

However, the conventional copper plating stripping solution using ammonium persulfate described above is preferable in that it does not corrode the iron substrate, but the stripping rate of the copper plating is low and the stripping treatment There was a problem that it took a long time. Further, the conventional copper plating stripper using ammonium dichromate does not corrode the iron substrate, but has a problem in waste liquid treatment. on the other hand,
Conventional stripping solution for stripping the copper thin film on the resin, for example, cupric chloride, ferric chloride and chlorine-containing alkaline etching solution, although the stripping rate of copper plating is high,
It is not practical because it involves corrosion of the iron substrate. The present invention is
The present invention has been made in view of the above circumstances, and an object thereof is to provide a stripping solution capable of stripping copper plating formed on an iron substrate with extremely low corrosion of the iron substrate. .

[0004]

In order to achieve such an object, the present invention is an alkaline aqueous solution containing a copper (II) ammine complex and an inhibitor, wherein the copper (II) ammine complex is a counterion. As a structure, it has an anion of an acid that is highly corrosive to the iron substrate.

In a more preferred embodiment of the present invention, the anion is a formic acid anion, the inhibitor is ammonium hydrogen carbonate, and the ammonium hydrogen carbonate concentration is 40 g / L or more. Further, the copper concentration is in the range of 10 to 120 g / L, and the pH is 8.5 or more.

In a more preferred embodiment of the present invention, the anion is a sulfuric acid anion, and the inhibitor is at least one of ammonium hydrogen carbonate, sodium hydrogen carbonate and sodium carbonate, and the ammonium hydrogen carbonate concentration is Is 50 g / L or more, or the sodium hydrogen carbonate concentration is 50 g / L or more and the copper concentration is 10
To 100 g / L, sodium carbonate concentration is 30 g / L or more and copper concentration is 30 to 100
The constitution was such that it was within the range of g / L, and the constitution was such that the pH was 8.5 or higher.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an optimum embodiment of the present invention will be described. The copper plating stripping solution on the iron substrate of the present invention is an alkaline aqueous solution containing a copper (II) ammine complex and an inhibitor, and the copper (II) ammine complex is a highly corrosive acid to the iron substrate as a counterion. It has anions.

In such a stripping solution of the present invention, since the contained copper (II) ammine complex acts as an oxidizing agent to dissolve and strip the copper plating on the iron substrate, a conventional stripping solution, for example, The stripping rate is higher than that of ammonium sulfate, etc., and the effect is further enhanced by increasing the concentration of the copper (II) ammine complex in the stripping solution. Further, the counter ion (anion of acid) constituting the copper (II) ammine complex has corrosiveness to the iron substrate, but the inhibitor suppresses the corrosion of the iron substrate by the acid, and therefore the stripping solution of the present invention is used for the iron substrate. Corrosion is extremely low.

Here, the anion of an acid having a high corrosiveness with respect to the iron substrate means the stripping solution containing the copper (II) ammine complex having this anion and containing no inhibitor, which is used as an anion on the iron substrate. It means that corrosion of the iron substrate occurs when the copper plating is peeled off. In the present invention, an inhibitor capable of exhibiting the effect of preventing corrosion of the iron substrate can be appropriately combined with the anion of the acid used. For example, when formic acid is used as the acid that is highly corrosive to the iron substrate, ammonium hydrogen carbonate can be used as the inhibitor. Further, when sulfuric acid is used as the acid having a high corrosiveness to the iron substrate, ammonium hydrogen carbonate, sodium carbonate, or sodium hydrogen carbonate can be used as the inhibitor. Then, the stripping solution of the present invention, the amount of counterions constituting the copper (II) ammine complex,
By adjusting the copper concentration and pH, the copper plating peeling rate can be arbitrarily controlled, and preferable conditions can be appropriately set.

Next, an embodiment of the present invention will be described by taking as an example the case where formic acid or sulfuric acid is used as an acid having a high corrosiveness with respect to an iron substrate.

(1) One embodiment of the copper plating stripping solution on the iron-based material of the present invention is an alkaline aqueous solution containing a copper (II) ammine complex and an inhibitor, and is used as a pair constituting the copper (II) ammine complex. Having an anion of formic acid as an ion,
In addition, it contains ammonium hydrogencarbonate as an inhibitor. In such a stripping solution of the present invention, since the contained copper (II) ammine complex acts as an oxidizing agent to dissolve and strip the copper plating on the iron substrate, the conventional stripping solution,
For example, the stripping rate is higher than that of ammonium persulfate and the like, and the effect is further enhanced by increasing the concentration of the copper (II) ammine complex in the stripping solution. Further, the counter ion (anion of formic acid) that constitutes the copper (II) ammine complex has corrosiveness to the iron substrate, but since the inhibitor ammonium hydrogen carbonate suppresses the corrosion of the iron substrate due to the anion of formic acid, The stripping solution of the present invention has extremely little corrosion of the iron substrate.

In the stripping solution of the present invention, the concentration of ammonium hydrogen carbonate as an inhibitor is 20 g / L or more, preferably 40 g / L or more, more preferably 50 g / L or more. If the concentration of ammonium hydrogen carbonate is less than 20 g / L, the effect of preventing the corrosion of the iron substrate by the anions of formic acid is insufficient, which is not preferable. Further, as described later, the pH of the stripping solution of the present invention is preferably 8.5 or more, but when the pH is 8 or more and less than 9, the concentration of ammonium hydrogen carbonate as an inhibitor is preferably 40 g / L or more.

In the stripping solution of the present invention, the copper concentration is 10 to 10.
It is within the range of 120 g / L. When the copper concentration is less than 10 g / L, the copper (II) ammine complex concentration in the stripping solution is low,
The action of the copper (II) ammine complex as an oxidant becomes insufficient, which hinders stripping of the copper plating. Also,
If the copper concentration exceeds 120 g / L, the amount of copper plating stripping treatment of the stripping solution decreases, and the practicality as a stripping solution becomes low.

In the stripping solution of the present invention, the pH is 8.5 or more, more preferably 9.0 or more. When the pH of the stripping solution is less than 8.5, the inhibitory effect on the iron substrate corrosion by the inhibitor becomes insufficient, and the formation of the copper (II) ammine complex is insufficient, so that a good copper plating stripping rate can be obtained. It is not preferable because it does not exist.

In the stripping solution of the present invention, the amount of the counter ion (anion of formic acid) per 1 mol of copper (II) is at least 1 time the stoichiometric number of mols forming the copper (II) ammine complex, It is preferably 1.2 times or more. Incidentally, the stripping treatment of the copper plating is repeated using the stripping solution of the present invention, and when the copper concentration in the processing solution becomes high, the counterion amount is the stoichiometric number of moles forming a copper (II) ammine complex. Excessive formic acid can be added to the stripping solution in advance so as not to fall below the range, or formic acid can be appropriately supplemented to the stripping solution.

When the stripping solution of the present invention is used to strip copper plating on an iron substrate, the temperature of the stripping solution (treatment bath) is not particularly limited, but is set in the range of 25 to 50 ° C., for example. Preferably. Stripping solution of the present invention, the amount of counterions constituting the copper (II) ammine complex, the copper concentration, by adjusting the pH in the above range, the copper plating stripping rate can be arbitrarily controlled, preferable conditions. It can be set appropriately.

(2) Another embodiment of the copper plating stripping solution on the iron-based material of the present invention is an alkaline aqueous solution containing a copper (II) ammine complex and an inhibitor, which constitutes a copper (II) ammine complex. Has an anion of sulfuric acid as a counter ion, and ammonium hydrogen carbonate as an inhibitor,
It contains at least one of sodium hydrogen carbonate and sodium carbonate. In such a stripping solution of the present invention, since the contained copper (II) ammine complex acts as an oxidizing agent to dissolve and strip the copper plating on the iron base, conventional stripping solutions, for example, ammonium persulfate, etc. Compared with this, the peeling speed is higher, and the effect is further enhanced by increasing the concentration of the copper (II) ammine complex in the peeling solution. Also, copper (II)
The anion of sulfuric acid forming the ammine complex has corrosiveness to the iron substrate, but since the inhibitor suppresses the corrosion of the iron substrate due to such counter ions, the stripping solution of the present invention has very little corrosion of the iron substrate. Becomes

In the stripping solution of the present invention, the concentration of ammonium hydrogen carbonate as an inhibitor is 50 g / L or more, more preferably 60 g / L or more. The concentration of sodium hydrogen carbonate as an inhibitor is 50 g / L or more,
It is more preferably 60 g / L or more. Furthermore, the concentration of sodium carbonate as an inhibitor is 30 g / L or more,
More preferably, it is 40 g / L or more. If the inhibitor concentration is less than the above concentration, the effect of preventing corrosion of the iron substrate by the anion of sulfuric acid becomes insufficient, which is not preferable.

In the stripping solution of the present invention, the copper concentration is in the range of 10 to 100 g / L when ammonium hydrogen carbonate or sodium hydrogen carbonate is used as the inhibitor, and 30 to 100 g / L when sodium carbonate is used as the inhibitor. Within the range. When the copper concentration is less than the above lower limit, the concentration of the copper (II) ammine complex in the stripping solution is low, and the action of the copper (II) ammine complex as an oxidizing agent becomes insufficient, which hinders stripping of copper plating. Will come. Further, if the copper concentration exceeds 100 g / L, the amount of copper plating stripping treatment of the stripping solution decreases, and the practicality as a stripping solution becomes low.

In the stripping solution of the present invention, the pH is 8.5 or more, more preferably 9.0 or more. When the pH of the stripping solution is less than 8.5, the inhibitory effect on the iron substrate corrosion by the inhibitor becomes insufficient, and the formation of the copper (II) ammine complex is insufficient, so that a good copper plating stripping rate can be obtained. It is not preferable because it does not exist. Further, in the stripping solution of the present invention, copper (I
I) The amount of counterion (anion of sulfuric acid) per mole is copper
(II) It is preferable that the amount is 1 times or more, preferably 1.2 times or more the stoichiometric number of moles forming the ammine complex.
Incidentally, the stripping treatment of the copper plating is repeated using the stripping solution of the present invention, and when the copper concentration in the processing solution becomes high, the counterion amount is the stoichiometric number of moles forming a copper (II) ammine complex. Excessive sulfuric acid may be added to the stripping solution in advance so as not to fall below the level, or the stripping solution may be supplemented with sulfuric acid as appropriate.

When the stripping solution of the present invention is used to strip copper plating on an iron substrate, the temperature of the stripping solution (treatment bath) is not particularly limited, but is set in the range of 25 to 50 ° C., for example. Preferably. Stripping solution of the present invention, the amount of counterions constituting the copper (II) ammine complex, the copper concentration, by adjusting the pH in the above range, the copper plating stripping rate can be arbitrarily controlled, preferable conditions. It can be set appropriately.

[0022]

EXAMPLES Next, the present invention will be described in more detail by showing examples.

[Example 1A] Seven kinds of alkaline aqueous solutions having the following compositions containing a copper (II) ammine complex having a formic acid anion as a counter ion and ammonium hydrogencarbonate as an inhibitor were prepared, and a stripping solution was prepared. (Sample 1A-1
.About.1A-7). Each stripping solution had the ammonium hydrogen carbonate concentration shown in Table 1 below and a pH of 9.
0, the amount of formic acid added in the preparation stage was 2.
4 mol (the stoichiometric number of mols for forming the copper (II) ammine complex by the anion of formic acid is 2 mol). Composition of stripping solution (Samples 1A-1 to 1A-7) Ammonium hydrogen carbonate ... Concentration shown in Table 1 87% Formic acid 120.0 g / L Cupric hydroxide 60 g / L (copper concentration) 25 % Ammonia water (for pH adjustment)… Appropriate amount ・ Ion-exchanged water… The balance

For comparison, a stripping solution having the following composition was prepared. Composition of stripper (comparative) Ammonium persulfate 70 g / L 25% ammonia water 300 mL / L Ion-exchanged water Remainder

Next, a round bar-shaped iron substrate having a diameter of 7 mm and a length of 165 mm was covered with copper plating (thickness: about 25 μm) from one end to 90 mm to obtain a sample to be peeled.
Then, the above-mentioned stripping solution (Samples 1A-1 to 1A-7) was used to prepare a treatment bath having a bath temperature of 50 ° C. and a liquid volume of 200 mL. The electrolytic degreasing treatment (60 ° C., 1 minute) and water washing (room temperature, 1 minute) were then immersed in the treatment bath to remove the copper plating. The presence or absence of corrosion of the iron substrate in this peeling treatment was observed, and the time required until the copper plating was completely peeled off was measured. The results are shown in Table 1 below.

Using the above stripping solution (comparative), a treatment bath having a bath temperature of 50 ° C. and a liquid volume of 200 mL was prepared. The electrolytic degreasing (60 ° C., 1 minute) and water washing (room temperature, 1 minute) were then immersed in the treatment bath to remove the copper plating. The presence or absence of corrosion of the iron substrate in this peeling treatment was observed, and the time required until the copper plating was completely peeled off was measured. The results are shown in Table 1 below.

[0027]

[Table 1]

As shown in Table 1, the stripping solutions of the present invention (Samples 1A-4 to 1A-7) having a sufficient content of ammonium hydrogen carbonate as an inhibitor did not corrode the iron substrate. The copper plating can be stripped, and the time required for stripping was significantly shorter than that of the conventional stripping solution (solution containing ammonium persulfate). On the other hand, a stripping solution having insufficient content of ammonium hydrogen carbonate as an inhibitor (Samples 1A-1 to 1A-3)
Although the time required for peeling was significantly shorter than that of a conventional stripping solution (ammonium persulfate-containing solution), they all corroded the iron substrate and could not be put to practical use.

Next, an alkaline aqueous solution having the following composition containing a copper (II) ammine complex having a formic acid anion as a counter ion and ammonium hydrogencarbonate as an inhibitor was prepared, and a stripping solution (Sample 1A-8) was prepared. ). The stripping solution had a pH of 9.0, and the amount of formic acid added in the preparation step was such that when the copper concentration was 120 g / L, the anion of formic acid was copper (I
I) It was set to 199.9 g / L corresponding to the stoichiometric mole number for forming an ammine complex. Composition of stripping solution (Sample 1A-8) -Ammonium hydrogencarbonate ... 40g / L-87% Formic acid ... 199.9g / L-Cupric hydroxide ... 60g / L (copper concentration) -25% ammonia water (pH adjustment) For)) Appropriate amount ・ Ion-exchanged water…

Next, the above stripping solution (Sample 1A-8) was used to prepare a treatment bath having a bath temperature of 50 ° C. and a liquid volume of 200 mL. Then, the degreasing treatment in which the electrolytic degreasing treatment (60 ° C., 1 minute) and the water-washed (room temperature, 1 minute) -treated sample described above were immersed in a treatment bath to peel off the copper plating was continuously performed. . In addition, one peeling treatment was performed on four specimens to be peeled at the same time. As a result, the copper concentration of the treatment liquid is 12
It was confirmed that the time required for one peeling treatment was as short as 5 to 10 minutes until reaching 0 g / L (the sixth treatment number), and was almost stable. However, when the copper concentration of the treatment liquid exceeded 120 g / L, the time required for one peeling treatment exceeded 30 minutes.

[Example 1B] Six kinds of alkaline aqueous solutions having the following compositions containing a copper (II) ammine complex having a formic acid anion as a counter ion and ammonium hydrogencarbonate as an inhibitor were prepared, and a stripping solution was prepared. (Sample 1B-1
.About.1B-6). The copper concentration of each stripping solution is shown in Table 2 below, the pH is 9.0, and the amount of formic acid added in the preparation stage is 2.4 mol per 1 mol of copper (the anion of formic acid is copper (II ) The stoichiometric number of moles for forming the ammine complex was 2 mol). Composition of stripper (Samples 1B-1 to 1B-6) -Ammonium hydrogen carbonate 20g / L-87% Formic acid 120.0g / L-Cupric hydroxide-Copper concentration shown in Table 2-25% ammonia water (For pH adjustment)… Appropriate amount ・ Ion-exchanged water… The balance

Next, in the same manner as in Example 1A, copper plating was formed on the iron substrate to prepare a sample to be peeled. Then, the above-mentioned stripping solutions (Samples 1B-1 to 1B-6) were used to prepare a treatment bath having a bath temperature of 50 ° C. and a liquid volume of 200 mL. And
The above delaminating sample that had been subjected to electrolytic degreasing treatment (60 ° C., 1 minute) and water washing (room temperature, 1 minute) was immersed in a treatment bath to peel off the copper plating. The presence or absence of corrosion of the iron substrate in this peeling treatment was observed, and the time required until the copper plating was completely peeled off was measured. The results are shown in Table 2 below.

[0033]

[Table 2]

As shown in Table 2, all of the stripping solutions of the present invention (Samples 1B-2 to 1B-6) are capable of stripping copper plating without corroding the iron base material. The time required was significantly shorter than that of the conventional stripping solution (solution containing ammonium persulfate) shown in Example 1A.

[Example 1C] Three kinds of alkaline aqueous solutions having the following composition containing a copper (II) ammine complex having a formic acid anion as a counter ion and ammonium hydrogencarbonate as an inhibitor were prepared, and a stripping solution was prepared. (Sample 1C-1
.About.1C-3). The amount of formic acid (the number of moles relative to 1 mol of copper and the amount added) at the preparation stage of each stripping solution was as shown in Table 3 below, and the pH was 9.0. still,
The stoichiometric number of moles for forming the copper (II) ammine complex by the formic acid anion is 2 moles relative to 1 mole of copper. Composition of stripping solution (Samples 1C-1 to 1C-3) -Ammonium hydrogen carbonate 20g / L-87% Formic acid-Concentration shown in Table 3 -Cupric hydroxide-60g / L (copper concentration) -25% Ammonia Water (for pH adjustment) ... Appropriate amount ・ Ion-exchanged water ... The balance

Next, in the same manner as in Example 1A, copper plating was formed on the iron substrate to prepare a sample to be peeled. Then, using the above-mentioned stripping solution (Samples 1C-1 to 1C-3), a treatment bath having a bath temperature of 50 ° C. and a liquid amount of 200 mL was prepared. And
The above delaminating sample that had been subjected to electrolytic degreasing treatment (60 ° C., 1 minute) and water washing (room temperature, 1 minute) was immersed in a treatment bath to peel off the copper plating. The presence or absence of corrosion of the iron substrate in this peeling treatment was observed, and the time required until the copper plating was completely peeled off was measured, and the results are shown in Table 3 below.

[0037]

[Table 3]

As shown in Table 3, each of the stripping solutions of the present invention (Samples 1C-1 to 1C-3) is capable of stripping copper plating without corroding the iron base material. The time required was significantly shorter than that of the conventional stripping solution (solution containing ammonium persulfate) shown in Example 1A.

[Example 1D] Five kinds of alkaline aqueous solutions having the following compositions containing a copper (II) ammine complex having a formic acid anion as a counter ion and ammonium hydrogencarbonate as an inhibitor were prepared, and a stripping solution was prepared. (Sample 1D-1
~ 1D-5). The pH and ammonium hydrogen carbonate concentration of each stripping solution are shown in Table 4 below, and the amount of formic acid added in the preparation step was 2.4 mol per 1 mol of copper (the anion of formic acid was copper (II ) The stoichiometric number of moles for forming the ammine complex was 2 mol). Composition of stripping solution (Samples 1D-1 to 1D-5) -Ammonium hydrogencarbonate ... Concentration shown in Table 4-87% Formic acid--120.0 g / L-Curic hydroxide-60 g / L (copper concentration) -25 % Ammonia water (for pH adjustment)… Appropriate amount ・ Ion-exchanged water… The balance

Then, in the same manner as in Example 1A, copper plating was formed on the iron substrate to prepare a sample to be peeled. Next, the above-mentioned stripping solutions (Samples 1D-1 to 1D-5) were used to prepare a treatment bath having a bath temperature of 50 ° C. and a liquid volume of 200 mL. And
The above delaminating sample that had been subjected to electrolytic degreasing treatment (60 ° C., 1 minute) and water washing (room temperature, 1 minute) was immersed in a treatment bath to peel off the copper plating. The presence or absence of corrosion of the iron substrate in this peeling treatment was observed, and the time required until the copper plating was completely peeled off was measured. The results are shown in Table 4 below.

[0041]

[Table 4]

As shown in Table 4, the stripping solution of the present invention having a content of ammonium hydrogen carbonate as an inhibitor of 20 g / L and a pH of 9 or more (Sample 1D-2)
1D-3) is capable of stripping copper plating without corroding the iron substrate, and the time required for stripping is longer than that of the conventional stripping solution (ammonium persulfate-containing solution) shown in Example 1A. Was also significantly shorter.

Further, the content of ammonium hydrogencarbonate as an inhibitor was 20 g / L, and the stripping solution (Sample 1D-1) having a pH of 8.5 had a conventional stripping solution (ammonium persulfate-containing solution) in the time required for stripping. Although much shorter than that, corrosion of the iron matrix was observed. However, by setting the content of ammonium hydrogen carbonate to 40 g / L (Sample 1D-5), the copper plating can be stripped without corroding the iron substrate, and the time required for stripping is the same as in Example 1.
It was significantly shorter than the conventional stripping solution shown in A (solution containing ammonium persulfate).

[Comparative Example 1] 2 having the following composition containing sodium carbonate or sodium hydrogencarbonate instead of ammonium hydrogencarbonate as an inhibitor and a copper (II) ammine complex having an anion of formic acid as a counterion. A seed alkaline solution was prepared and used as a stripping solution (Comparative Samples 1-1 and 1-2). The pH of each stripper was 9.
0, the amount of formic acid added in the preparation stage was 2.
4 mol (the stoichiometric number of mols for forming the copper (II) ammine complex by the anion of formic acid is 2 mol). Composition of stripping solution (Comparative Sample 1-1): Sodium carbonate: 40 g / L, 87% formic acid: 120.0 g / L, cupric hydroxide: 60 g / L (copper concentration), 25% ammonia water (pH adjustment) For :) Appropriate amount ・ Ion-exchanged water… Remainder stripping solution (Comparative Sample 1-2) composition・ Sodium hydrogencarbonate… 40 g / L ・ 87% formic acid… 120.0 g / L ・ Curic hydroxide… 60 g / L ( Copper concentration) ・ 25% ammonia water (for pH adjustment)… Appropriate amount ・ Ion-exchanged water… The rest

Next, in the same manner as in Example 1A, copper plating was formed on the iron base material to obtain a sample to be peeled. Then, using the above-mentioned stripping solutions (Comparative Samples 1-1 and 1-2), a treatment bath having a bath temperature of 50 ° C. and a liquid volume of 200 mL was prepared. And
The above delaminating sample that had been subjected to electrolytic degreasing treatment (60 ° C., 1 minute) and water washing (room temperature, 1 minute) was immersed in a treatment bath to peel off the copper plating. The presence or absence of corrosion of the iron substrate in this peeling treatment was observed, and the time required until the copper plating was completely peeled off was measured. The results are shown in Table 5 below.

[0046]

[Table 5]

As shown in Table 5, instead of ammonium hydrogen carbonate as an inhibitor, sodium carbonate,
Alternatively, the stripping solution containing sodium hydrogen carbonate (Comparative Samples 1-1 and 1-2) is longer than the conventional stripping solution (ammonium persulfate-containing solution) shown in Example 1A in the time required for stripping copper plating. Although much shorter, they all corroded the iron matrix. From this, it was clarified that sodium carbonate and sodium hydrogen carbonate do not act as inhibitors for inhibiting corrosion of iron substrate.

[Example 2A] Seven kinds of alkaline aqueous solutions having the following compositions containing a copper (II) ammine complex having an anion of sulfuric acid as a counter ion and ammonium hydrogencarbonate as an inhibitor were prepared, and a stripping solution was prepared. (Sample 2A-1
2A-7). Each stripping solution had the ammonium hydrogen carbonate concentration shown in Table 6 below and a pH of 9.
0, the amount of sulfuric acid added in the preparation stage was 1.
2 moles (the stoichiometric mole number for the anion of sulfuric acid to form a copper (II) ammine complex is 1 mole). Composition of stripping solution (Samples 2A-1 to 2A-7) -Ammonium hydrogen carbonate ... Concentration shown in Table 6-95% Sulfuric acid--58.5 g / L-Cupric hydroxide--30 g / L (copper concentration) -25 % Ammonia water (for pH adjustment)… Appropriate amount ・ Ion-exchanged water… The balance

Then, in the same manner as in Example 1A, copper plating was formed on the iron substrate to prepare a sample to be peeled. Then, using the above-mentioned stripping solution (Samples 2A-1 to 2A-7), a treatment bath having a bath temperature of 50 ° C. and a liquid amount of 200 mL was prepared. And
The above delaminating sample that had been subjected to electrolytic degreasing treatment (60 ° C., 1 minute) and water washing (room temperature, 1 minute) was immersed in a treatment bath to peel off the copper plating. The presence or absence of corrosion of the iron substrate in this peeling treatment was observed, and the time required until the copper plating was completely peeled off was measured, and the results are shown in Table 6 below.

[0050]

[Table 6]

As shown in Table 6, the stripping solutions of the present invention (Samples 2A-5 to 2A-7) having a sufficient content of ammonium hydrogencarbonate as an inhibitor did not corrode the iron substrate. The copper plating was peelable, and the time required for peeling was significantly shorter than that of the conventional stripping solution (ammonium persulfate-containing solution) shown in Example 1A. On the other hand, a stripping solution with insufficient content of ammonium hydrogen carbonate as an inhibitor (Sample 2
A-1 to 2A-4), although the time required for peeling is significantly shorter than the conventional peeling liquid (ammonium persulfate-containing solution), all corrode the iron substrate and cannot be put to practical use. there were.

Then, an alkaline aqueous solution having the following composition containing a copper (II) ammine complex having a sulfuric acid anion as a counter ion and ammonium hydrogencarbonate as an inhibitor was prepared, and a stripping solution (Sample 2A-8) was prepared. And This stripping solution had a pH of 9.0, and the amount of sulfuric acid added in the preparation step was such that when the copper concentration was 100 g / L, the anion of sulfuric acid was copper (I
I) The amount was 162.4 g / L, which corresponds to the stoichiometric number of moles for forming an ammine complex. Composition of stripping solution (Sample 2A-8) -Ammonium hydrogen carbonate ... 50g / L-95% sulfuric acid ... 162.4g / L-Cupric hydroxide ... 60g / L (copper concentration) -25% ammonia water (pH adjustment) For)) Appropriate amount ・ Ion-exchanged water…

Next, the above stripping solution (Sample 2A-8) was used to prepare a treatment bath having a bath temperature of 50 ° C. and a liquid volume of 200 mL. Then, the degreasing treatment in which the electrolytic degreasing treatment (60 ° C., 1 minute) and the water-washed (room temperature, 1 minute) -treated sample described above were immersed in a treatment bath to peel off the copper plating was continuously performed. . In addition, one peeling treatment was performed on four specimens to be peeled at the same time. As a result, the copper concentration of the treatment liquid is 10
It was confirmed that the time required for one peeling treatment was as short as 5 to 10 minutes and was almost stable until reaching 0 g / L (the seventh treatment). However, when the copper concentration of the treatment liquid exceeded 100 g / L, the time required for one peeling treatment exceeded 70 minutes.

[Example 2B] Six kinds of alkaline aqueous solutions having the following compositions containing a copper (II) ammine complex having an anion of sulfuric acid as a counter ion and ammonium hydrogencarbonate as an inhibitor were prepared to prepare a stripping solution. (Sample 2B-1
2B-6). The copper concentration of each stripper is shown in Table 7 below, the pH is 9.0, and the amount of sulfuric acid added in the preparation step is 1.2 mol per mol of copper (the anion of sulfuric acid is copper (II ) The stoichiometric number of moles for forming the ammine complex was 1 mole). Composition of stripping solution (Samples 2B-1 to 2B-6) -Ammonium hydrogen carbonate ... 50 g / L-95% sulfuric acid ... 58.5 g / L-Curic hydroxide ... Copper concentration shown in Table 7-25% ammonia water (For pH adjustment)… Appropriate amount ・ Ion-exchanged water… The balance

Next, in the same manner as in Example 1A, copper plating was formed on the iron substrate to prepare a sample to be peeled. Then, using the above-mentioned stripping solution (Samples 2B-1 to 2B-6), a treatment bath having a bath temperature of 50 ° C. and a liquid amount of 200 mL was prepared. And
The above delaminating sample that had been subjected to electrolytic degreasing treatment (60 ° C., 1 minute) and water washing (room temperature, 1 minute) was immersed in a treatment bath to peel off the copper plating. The presence or absence of corrosion of the iron substrate in this peeling treatment was observed, and the time required until the copper plating was completely peeled off was measured. The results are shown in Table 7 below.

[0056]

[Table 7]

As shown in Table 7, each of the stripping solutions of the present invention (Samples 2B-2 to 2B-6) is capable of stripping copper plating without corroding the iron base material. The time required was significantly shorter than that of the conventional stripping solution (solution containing ammonium persulfate) shown in Example 1A.

[Example 2C] Four kinds of alkaline aqueous solutions having the following compositions containing a copper (II) ammine complex having an anion of sulfuric acid as a counter ion and ammonium hydrogencarbonate as an inhibitor were prepared, and a stripping solution was prepared. (Sample 2C-1
2C-4). The amount of sulfuric acid (the number of moles relative to 1 mol of copper and the amount of addition) added at the preparation stage of each stripping solution was as shown in Table 8 below, and the pH was 9.0. still,
The stoichiometric number of moles for the anion of sulfuric acid to form a copper (II) ammine complex is 1 mole per 1 mole of copper. Composition of stripping solution (Samples 2C-1 to 2C-4) -Ammonium hydrogen carbonate ... 50 g / L-95% sulfuric acid-Concentration shown in Table 8 -Cupric hydroxide ... 30 g / L (copper concentration) -25% ammonia Water (for pH adjustment) ... Appropriate amount ・ Ion-exchanged water ... The balance

Next, in the same manner as in Example 1A, copper plating was formed on the iron substrate to prepare a sample to be peeled. Then, using the above-mentioned stripping solution (Samples 2C-1 to 2C-4), a treatment bath having a bath temperature of 50 ° C. and a liquid amount of 200 mL was prepared. And
The above delaminating sample that had been subjected to electrolytic degreasing treatment (60 ° C., 1 minute) and water washing (room temperature, 1 minute) was immersed in a treatment bath to peel off the copper plating. The presence or absence of corrosion of the iron substrate in this peeling treatment was observed, and the time required until the copper plating was completely peeled off was measured. The results are shown in Table 8 below.

[0060]

[Table 8]

As shown in Table 8, each of the stripping solutions of the present invention (Samples 2C-1 to 2C-4) is capable of stripping copper plating without corroding the iron base material, and is also suitable for stripping. The time required was significantly shorter than that of the conventional stripping solution (solution containing ammonium persulfate) shown in Example 1A.

[Example 2D] Four kinds of alkaline aqueous solutions having the following composition containing a copper (II) ammine complex having a sulfuric acid anion as a counter ion and ammonium hydrogencarbonate as an inhibitor were prepared, and a stripping solution was prepared. (Sample 2D-1
2D-4). The pH of each stripper is shown in Table 9 below.
The amount of sulfuric acid added in the preparation step is 1.2 mol per mol of copper (the stoichiometric amount of mol of the anion of sulfuric acid forms a copper (II) ammine complex is 1 mol). And Composition of stripper (Samples 2D-1 to 2D-4) -Ammonium hydrogen carbonate ... 50 g / L-95% sulfuric acid ... 58.5 g / L-Cupric hydroxide ... 30 g / L (copper concentration) -25% ammonia Water (for pH adjustment) ... Appropriate amount ・ Ion-exchanged water ... The balance

Next, in the same manner as in Example 1A, copper plating was formed on the iron substrate to prepare a sample to be peeled. Next, using the above-mentioned stripping solution (Samples 2D-1 to 2D-4), a treatment bath having a bath temperature of 50 ° C. and a liquid volume of 200 mL was prepared. And
The above delaminating sample that had been subjected to electrolytic degreasing treatment (60 ° C., 1 minute) and water washing (room temperature, 1 minute) was immersed in a treatment bath to peel off the copper plating. The presence or absence of corrosion of the iron substrate in this peeling treatment was observed, and the time required until the copper plating was completely peeled off was measured, and the results are shown in Table 9 below.

[0064]

[Table 9]

As shown in Table 9, each of the stripping solutions of the present invention (Samples 2D-1 to 2D-4) is capable of stripping copper plating without corroding the iron base material, and is also suitable for stripping. The time required was significantly shorter than that of the conventional stripping solution (solution containing ammonium persulfate) shown in Example 1A.

[Example 3A] Seven kinds of alkaline aqueous solutions having the following compositions containing a copper (II) ammine complex having a sulfuric acid anion as a counter ion and sodium carbonate as an inhibitor were prepared, and a stripping solution ( Samples 3A-1 to 3A
-7). The sodium carbonate concentration of each stripping solution is shown in Table 10 below, the pH was 9.5, and the amount of sulfuric acid added in the preparation stage was 1.2 mol per 1 mol of copper (sulfuric acid anion). Is a stoichiometric number of moles for forming a copper (II) ammine complex. Composition of stripping solution (Samples 3A-1 to 3A-7) Sodium carbonate ... Concentration shown in Table 10 95% Sulfuric acid 58.5 g / L Cupric hydroxide 30 g / L (copper concentration) 25% Ammonia water (for pH adjustment)… Appropriate amount ・ Ion exchange water… The rest

Next, in the same manner as in Example 1A, copper plating was formed on the iron base material to obtain a sample to be peeled. Next, using the above-mentioned stripping solution (Samples 3A-1 to 3A-7), a treatment bath having a bath temperature of 50 ° C. and a liquid amount of 200 mL was prepared. And
The above delaminating sample that had been subjected to electrolytic degreasing treatment (60 ° C., 1 minute) and water washing (room temperature, 1 minute) was immersed in a treatment bath to peel off the copper plating. The presence or absence of corrosion of the iron substrate in this peeling treatment was observed, and the time required until the copper plating was completely peeled off was measured. The results are shown in Table 10 below.

[0068]

[Table 10]

As shown in Table 10, all of the stripping solutions of the present invention (Samples 3A-3 to 3A-5) having a sufficient content of sodium carbonate as an inhibitor did not corrode the iron substrate and did not corrode the copper. It is possible to remove the plating, and
The time required for stripping was significantly shorter than that of the conventional stripping solution (ammonium persulfate-containing solution) shown in Example 1A. The stripping solution of the present invention (Samples 3A-6 to 3A-
Regarding 7), although the time required for stripping is long under the conditions of this embodiment (pH 9.5), when 25% ammonia water was added to adjust the pH to 10.0, the above stripping solution (Sample 3) was used.
The peeling similar to A-3 to 3A-5) was possible. This is the result shown in Example 3D described later (p of the treatment liquid).
(The time required for stripping is shortened by increasing H)), and the stripping solution of the present invention can arbitrarily control the copper plating stripping rate by adjusting the pH, the copper concentration, and the like. It was confirmed that it was possible. On the other hand, the stripping solutions (Samples 3A-1 to 3A-2) in which the content of sodium carbonate as an inhibitor is insufficient have a significantly larger time required for stripping than the conventional stripping solutions (solutions containing ammonium persulfate). Although they were short, they all corroded the iron substrate and could not be put to practical use.

Next, an alkaline aqueous solution having the following composition containing a copper (II) ammine complex having an anion of sulfuric acid as a counter ion and sodium carbonate as an inhibitor was prepared and used as a stripping solution (Sample 3A-8). did. This stripping solution has a pH of 9.5, and the amount of sulfuric acid added in the preparation step corresponds to the stoichiometric number of moles for the anion of sulfuric acid to form a copper (II) ammine complex when the copper concentration is 100 g / L. Do 1
It was 62.4 g / L. Composition of stripping solution (Sample 3A-8) -Sodium carbonate ... 30g / L-95% sulfuric acid ... 162.4g / L-Curic hydroxide ... 60g / L (copper concentration) -25% ammonia water (for pH adjustment) )… Appropriate amount of ion-exchanged water… The balance

Next, using the above-mentioned stripping solution (Sample 3A-8), a processing bath having a bath temperature of 50 ° C. and a liquid volume of 200 mL was prepared. Then, the degreasing treatment in which the electrolytic degreasing treatment (60 ° C., 1 minute) and the water-washed (room temperature, 1 minute) -treated sample described above were immersed in a treatment bath to peel off the copper plating was continuously performed. . In addition, one peeling treatment was performed on four specimens to be peeled at the same time. As a result, the copper concentration of the treatment liquid is 10
It was confirmed that the time required for one peeling treatment was as short as 20 to 25 minutes until reaching 0 g / L (the seventh treatment number), and was almost stable. However, when the copper concentration of the treatment liquid exceeded 100 g / L, the time required for one peeling treatment exceeded 40 minutes.

[Example 3B] Five kinds of alkaline aqueous solutions having the following composition containing a copper (II) ammine complex having an anion of sulfuric acid as a counter ion and sodium carbonate as an inhibitor were prepared, and a stripping solution ( Samples 3B-1 to 3B
-5). The copper concentration of each stripper is shown in Table 11 below, the pH is 9.5, and the amount of sulfuric acid added in the preparation stage is 1.2 mol per mol of copper (the anion of sulfuric acid is copper (I
I) The stoichiometric number of moles for forming the ammine complex was 1 mole). Composition of stripping solution (Samples 3B-1 to 3B-5) -Sodium carbonate ... 30g / L-95% sulfuric acid--58.5g / L-Cupric hydroxide-Copper concentration shown in Table-11-25% ammonia water ( (For pH adjustment) ... Appropriate amount ・ Ion-exchanged water ... Remainder

Next, in the same manner as in Example 1A, copper plating was formed on the iron base material to obtain a sample to be peeled. Then, using the above-mentioned stripping solution (Samples 3B-1 to 3B-5), a treatment bath having a bath temperature of 50 ° C. and a liquid amount of 200 mL was prepared. And
The above delaminating sample that had been subjected to electrolytic degreasing treatment (60 ° C., 1 minute) and water washing (room temperature, 1 minute) was immersed in a treatment bath to peel off the copper plating. The presence or absence of corrosion of the iron substrate in this peeling treatment was observed, and the time required until the copper plating was completely peeled off was measured, and the results are shown in Table 11 below.

[0074]

[Table 11]

As shown in Table 11, all of the stripping solutions of the present invention (Samples 3B-2 to 3B-5) are capable of stripping copper plating without corroding the iron base material, The time required was significantly shorter than that of the conventional stripping solution (solution containing ammonium persulfate) shown in Example 1A.

[Example 3C] Four kinds of alkaline aqueous solutions having the following composition containing a copper (II) ammine complex having an anion of sulfuric acid as a counter ion and sodium carbonate as an inhibitor were prepared, and a stripping solution ( Samples 3C-1 to 3C
-4). The amount of sulfuric acid added at the preparation stage of each stripping solution (the number of moles with respect to 1 mol of copper, and the amount of addition) was as shown in Table 12 below, and the pH was 9.5. The stoichiometric number of moles for the anion of sulfuric acid to form a copper (II) ammine complex is 1 mole per 1 mole of copper. Composition of stripper (Samples 3C-1 to 3C-4) -Sodium carbonate ... 30g / L-95% sulfuric acid-Concentration shown in Table 12 -Cupric hydroxide ... 30g / L (copper concentration) -25% ammonia water (For pH adjustment)… Appropriate amount ・ Ion-exchanged water… The balance

Then, in the same manner as in Example 1A, copper plating was formed on the iron substrate to prepare a sample to be peeled. Then, using the above-mentioned stripping solution (Samples 3C-1 to 3C-4), a treatment bath having a bath temperature of 50 ° C. and a liquid amount of 200 mL was prepared. And
The above delaminating sample that had been subjected to electrolytic degreasing treatment (60 ° C., 1 minute) and water washing (room temperature, 1 minute) was immersed in a treatment bath to peel off the copper plating. The presence or absence of corrosion of the iron substrate in this peeling treatment was observed, and the time required until the copper plating was completely peeled off was measured, and the results are shown in Table 12 below.

[0078]

[Table 12]

As shown in Table 12, all of the stripping solutions of the present invention (Samples 3C-1 to 3C-4) are capable of stripping copper plating without corroding the iron base material. The time required was significantly shorter than that of the conventional stripping solution (solution containing ammonium persulfate) shown in Example 1A.

[Example 3D] Four kinds of alkaline aqueous solutions having the following compositions containing a copper (II) ammine complex having a sulfuric acid anion as a counter ion and sodium carbonate as an inhibitor were prepared, and a stripping solution ( Samples 3D-1 to 3D
-4). The pH of each stripping solution is shown in Table 13 below, and the amount of sulfuric acid added in the preparation step was 1.2 mol per mol of copper (the anion of sulfuric acid formed a copper (II) ammine complex). The stoichiometric number of moles was 1 mol). Composition of stripping solution (Samples 3D-1 to 3D-4) -Sodium carbonate ... 30g / L-95% sulfuric acid--58.5g / L-Curic hydroxide ... 30g / L (copper concentration) -25% ammonia water (For pH adjustment)… Appropriate amount ・ Ion-exchanged water… The balance

Then, in the same manner as in Example 1A, copper plating was formed on the iron substrate to prepare a sample to be peeled. Next, using the above-mentioned stripping solution (Samples 3D-1 to 3D-4), a treatment bath having a bath temperature of 50 ° C. and a liquid amount of 200 mL was prepared. And
The above delaminating sample that had been subjected to electrolytic degreasing treatment (60 ° C., 1 minute) and water washing (room temperature, 1 minute) was immersed in a treatment bath to peel off the copper plating. The presence or absence of corrosion of the iron substrate in this peeling treatment was observed, and the time required until the copper plating was completely peeled off was measured. The results are shown in Table 13 below.

[0082]

[Table 13]

As shown in Table 13, all of the stripping solutions of the present invention (Samples 3D-1 to 3D-4) are capable of stripping copper plating without corroding the iron substrate, The time required was significantly shorter than that of the conventional stripping solution (solution containing ammonium persulfate) shown in Example 1A.

[Example 4A] Six kinds of alkaline aqueous solutions having the following compositions containing a copper (II) ammine complex having an anion of sulfuric acid as a counter ion and sodium hydrogencarbonate as an inhibitor were prepared, and a stripping solution was prepared. (Sample 4A-1 ~
4A-6). Each stripping solution had the sodium hydrogen carbonate concentration shown in Table 14 below and a pH of 9.
0, the amount of sulfuric acid added in the preparation stage was 1.
2 moles (the stoichiometric mole number for the anion of sulfuric acid to form a copper (II) ammine complex is 1 mole). Composition of stripping solution (Samples 4A-1 to 4A-6) -Sodium hydrogencarbonate ... Concentration shown in Table 14-95% Sulfuric acid--58.5 g / L-Cupric hydroxide--30 g / L (copper concentration) -25 % Ammonia water (for pH adjustment)… Appropriate amount ・ Ion-exchanged water… The balance

Then, in the same manner as in Example 1A, copper plating was formed on the iron substrate to prepare a sample to be peeled. Next, the above-mentioned stripping solution (Samples 4A-1 to 4A-6) was used to prepare a treatment bath having a bath temperature of 50 ° C. and a liquid amount of 200 mL. And
The above delaminating sample that had been subjected to electrolytic degreasing treatment (60 ° C., 1 minute) and water washing (room temperature, 1 minute) was immersed in a treatment bath to peel off the copper plating. The presence or absence of corrosion of the iron substrate in this peeling treatment was observed, and the time required until the copper plating was completely peeled off was measured. The results are shown in Table 14 below.

[0086]

[Table 14]

As shown in Table 14, the stripping solutions of the present invention (Samples 4A-4 to 4A-6) having a sufficient content of sodium hydrogen carbonate as an inhibitor did not corrode the iron substrate. The copper plating was peelable, and the time required for peeling was significantly shorter than that of the conventional stripping solution (ammonium persulfate-containing solution) shown in Example 1A. On the other hand, a stripping solution with an insufficient content of sodium hydrogen carbonate as an inhibitor (Sample 4A
-1 to 4A-3), although the time required for peeling is significantly shorter than that of the conventional stripping solution (ammonium persulfate-containing solution), all of them corrode the iron substrate and cannot be put to practical use. It was

Then, an alkaline aqueous solution having the following composition containing a copper (II) ammine complex having a sulfuric acid anion as a counter ion and sodium hydrogen carbonate as an inhibitor was prepared, and a stripping solution (Sample 4A-7) was prepared. And This stripping solution had a pH of 9.0, and the amount of sulfuric acid added in the preparation stage was
When the copper concentration was 100 g / L, the amount was 162.4 g / L, which corresponds to the stoichiometric mole number for the sulfuric acid anion to form a copper (II) ammine complex. Composition of stripping solution (Sample 4A-7) -Sodium hydrogencarbonate ... 50g / L-95% sulfuric acid ... 162.4g / L-Cupric hydroxide ... 60g / L (copper concentration) -25% ammonia water (pH adjustment) For)) Appropriate amount ・ Ion-exchanged water…

Next, using the above-mentioned stripping solution (Sample 4A-7), a treatment bath having a bath temperature of 50 ° C. and a liquid volume of 200 mL was prepared. Then, the degreasing treatment in which the electrolytic degreasing treatment (60 ° C., 1 minute) and the water-washed (room temperature, 1 minute) -treated sample described above were immersed in a treatment bath to peel off the copper plating was continuously performed. . In addition, one peeling treatment was performed on four specimens to be peeled at the same time. As a result, the copper concentration of the treatment liquid is 10
It was confirmed that the time required for one peeling treatment was as short as 10 to 20 minutes and was almost stable until it reached 0 g / L (the seventh treatment). However, when the copper concentration of the treatment liquid exceeded 100 g / L, the time required for one peeling treatment exceeded 30 minutes.

[Example 4B] Six kinds of alkaline aqueous solutions having the following compositions containing a copper (II) ammine complex having an anion of sulfuric acid as a counter ion and sodium hydrogen carbonate as an inhibitor were prepared, and a stripping solution was prepared. (Sample 4B-1 to
4B-6). The copper concentration of each stripper is shown in Table 15 below, the pH is 9.0, and the amount of sulfuric acid added in the preparation step is 1.2 mol per mol of copper (the anion of sulfuric acid is copper (II ) The stoichiometric number of moles for forming the ammine complex was 1 mole). Composition of stripping solution (Samples 4B-1 to 4B-6) Sodium hydrogencarbonate 50 g / L 95% Sulfuric acid 58.5 g / L Cupric hydroxide Copper concentration shown in Table 15 25% ammonia water (For pH adjustment)… Appropriate amount ・ Ion-exchanged water… The balance

Next, in the same manner as in Example 1A, copper plating was formed on the iron substrate to prepare a sample to be peeled. Next, the above-mentioned stripping solutions (Samples 4B-1 to 4B-6) were used to prepare a treatment bath having a bath temperature of 50 ° C. and a liquid volume of 200 mL. And
The above delaminating sample that had been subjected to electrolytic degreasing treatment (60 ° C., 1 minute) and water washing (room temperature, 1 minute) was immersed in a treatment bath to peel off the copper plating. The presence or absence of corrosion of the iron substrate in this peeling treatment was observed, and the time required until the copper plating was completely peeled off was measured. The results are shown in Table 15 below.

[0092]

[Table 15]

As shown in Table 15, each of the stripping solutions of the present invention (Samples 4B-2 to 4B-6) is capable of stripping copper plating without corroding the iron base material, and is also suitable for stripping. The time required was significantly shorter than that of the conventional stripping solution (solution containing ammonium persulfate) shown in Example 1A.

[Example 4C] Four kinds of alkaline aqueous solutions having the following compositions containing a copper (II) ammine complex having an anion of sulfuric acid as a counter ion and sodium hydrogen carbonate as an inhibitor were prepared, and a stripping solution was prepared. (Sample 4C-1 to
4C-4). The amount of sulfuric acid added in the preparation stage of each stripping solution (the number of moles with respect to 1 mol of copper, and the amount added) is as shown in Table 16 below, and the pH was 9.0. still,
The stoichiometric number of moles for the anion of sulfuric acid to form a copper (II) ammine complex is 1 mole per 1 mole of copper. Composition of stripping solution (Samples 4C-1 to 4C-4) -Sodium hydrogencarbonate 50g / L-95% sulfuric acid-Concentration shown in Table 16 -Cupric hydroxide 30g / L (copper concentration) -25% Ammonia Water (for pH adjustment) ... Appropriate amount ・ Ion-exchanged water ... The balance

Then, in the same manner as in Example 1A, copper plating was formed on the iron substrate to prepare a sample to be peeled. Next, using the above-mentioned stripping solution (Samples 4C-1 to 4C-4), a treatment bath having a bath temperature of 50 ° C. and a liquid amount of 200 mL was prepared. And
The above delaminating sample that had been subjected to electrolytic degreasing treatment (60 ° C., 1 minute) and water washing (room temperature, 1 minute) was immersed in a treatment bath to peel off the copper plating. The presence or absence of corrosion of the iron substrate in this peeling treatment was observed, and the time required until the copper plating was completely peeled off was measured, and the results are shown in Table 16 below.

[0096]

[Table 16]

As shown in Table 16, each of the stripping solutions of the present invention (Samples 4C-1 to 4C-4) is capable of stripping copper plating without corroding the iron base material, and is also suitable for stripping. The time required was significantly shorter than that of the conventional stripping solution (solution containing ammonium persulfate) shown in Example 1A.

[Example 4D] Four kinds of alkaline aqueous solutions having the following compositions containing a copper (II) ammine complex having an anion of sulfuric acid as a counter ion and sodium hydrogen carbonate as an inhibitor were prepared, and a stripping solution was prepared. (Sample 4D-1 to 4D-1
4D-4). The pH of each stripper is shown in Table 17 below.
The amount of sulfuric acid added in the preparation step is 1.2 mol per 1 mol of copper (the stoichiometric number of mols for the anion of sulfuric acid to form a copper (II) ammine complex is 1 mol). And Composition of stripping solution (Samples 4D-1 to 4D-4) -Sodium hydrogencarbonate ... 50g / L-95% sulfuric acid ... 58.5g / L-Cupric hydroxide ... 30g / L (copper concentration) -25% ammonia Water (for pH adjustment) ... Appropriate amount ・ Ion-exchanged water ... The balance

Then, in the same manner as in Example 1A, copper plating was formed on the iron substrate to prepare a sample to be peeled. Then, using the above-mentioned stripping solution (Samples 4D-1 to 4D-4), a treatment bath having a bath temperature of 50 ° C. and a liquid amount of 200 mL was prepared. And
The above delaminating sample that had been subjected to electrolytic degreasing treatment (60 ° C., 1 minute) and water washing (room temperature, 1 minute) was immersed in a treatment bath to peel off the copper plating. The presence or absence of corrosion of the iron substrate in this peeling treatment was observed, and the time required until the copper plating was completely peeled off was measured. The results are shown in Table 17 below.

[0100]

[Table 17]

As shown in Table 17, each of the stripping solutions of the present invention (Samples 4D-1 to 4D-4) is capable of stripping copper plating without corroding the iron base material, and is also suitable for stripping. The time required was significantly shorter than that of the conventional stripping solution (solution containing ammonium persulfate) shown in Example 1A.

[Comparative Example 2] Five kinds of alkaline aqueous solutions having the following composition containing a copper (II) ammine complex having an anion of phthalic acid as a counter ion were prepared to prepare stripper solutions (Comparative Samples 2-1 to 2-2). -5). The pH of each stripper was 9.0 and the copper concentration was as shown in Table 18 below. The amount of phthalic acid added in the preparation stage (the number of moles per mole of copper and the amount added) was as shown in Table 18 below. As shown. still,
The number of moles of stoichiometry for forming the copper (II) ammine complex by the anion of phthalic acid is 1 mole per 1 mole of copper. Composition of stripping solution (Comparative Samples 2-1 to 2-5) -Phthalic acid-Concentration shown in Table 18- Cupric hydroxide-Copper concentration shown in Table- 18-25 % ammonia water (for pH adjustment) -Proper amount- Ion-exchanged water ... The rest

Then, in the same manner as in Example 1A, copper plating was formed on the iron substrate to prepare a sample to be peeled. Then, using the above-mentioned stripping solution (Comparative Samples 2-1 to 2-5), a treatment bath having a bath temperature of 50 ° C. and a liquid amount of 200 mL was prepared. And
The above delaminating sample that had been subjected to electrolytic degreasing treatment (60 ° C., 1 minute) and water washing (room temperature, 1 minute) was immersed in a treatment bath to peel off the copper plating. The presence or absence of corrosion of the iron substrate in this peeling treatment was observed, and the time required until the copper plating was completely peeled off was measured. The results are shown in Table 18 below.

[0104]

[Table 18]

As shown in Table 18, the stripping of the copper plating with the stripping solution containing the copper (II) ammine complex having the anion of phthalic acid as the counter ion (Comparative Samples 2-1 to 2-5) It was impossible. No corrosion of the iron base material occurred.

[Comparative Example 3] Five kinds of alkaline aqueous solutions having the following composition containing a copper (II) ammine complex having an anion of phenolsulfonic acid as a counter ion were prepared, and stripping solutions (Comparative Samples 3-1 to 3-1) were prepared. 3-5). Each stripper is
The pH was set to 9.0, the copper concentration was as shown in Table 20 below, and the amount of phenolsulfonic acid added in the preparation stage (copper 1
The number of moles relative to the moles and the addition amount) are shown in Table 19 below.
As shown in. The stoichiometric number of moles for the anion of phenolsulfonic acid to form a copper (II) ammine complex is 1 mole per 1 mole of copper. Composition of stripping solution (Comparative Samples 3-1 to 3-5) -Phenolsulfonic acid ... Concentration shown in Table 19- Cupric hydroxide ... Copper concentration shown in Table- 19-25 % ammonia water (for pH adjustment) ... Appropriate amount・ Ion-exchanged water ... The rest

Then, in the same manner as in Example 1A, copper plating was formed on the iron substrate to prepare a sample to be peeled. Then, using the above-mentioned stripping solution (Comparative Samples 3-1 to 3-5), a treatment bath having a bath temperature of 50 ° C. and a liquid amount of 200 mL was prepared. And
The above-described sample to be stripped, which had been subjected to electrolytic degreasing treatment (60 ° C., 1 minute) and water washing (room temperature, 1 minute), was immersed in a treatment bath to strip copper plating. The presence or absence of corrosion of the iron substrate in this peeling treatment was observed, and the time required until the copper plating was completely peeled off was measured, and the results are shown in Table 19 below.

[0108]

[Table 19]

As shown in Table 19, stripping of copper plating with a stripping solution (Comparative Samples 3-1 to 3-5) containing a copper (II) ammine complex having an anion of phenolsulfonic acid as a counter ion. Was impossible. No corrosion of the iron base material occurred.

[Comparative Example 4] Five kinds of alkaline aqueous solutions having the following composition containing a copper (II) ammine complex having a chloride ion as a counter ion and ammonium hydrogencarbonate as an inhibitor were prepared, and a stripping solution (comparative example) was prepared. Samples 4-1-4
-5). Each stripping solution had the ammonium hydrogen carbonate concentration shown in Table 20 below and a pH of 9.0.
The amount of chloride ions added in the preparation stage was 2.4 mol per mol of copper (the stoichiometric number of mols for the chloride ions to form a copper (II) ammine complex was 2 mol). Composition of stripping solution (Comparative Samples 4-1 to 4-5) -Ammonium hydrogen carbonate ... Concentration shown in Table 20-36% hydrochloric acid ... 114.7 g / L-Cupric hydroxide ... 30 g / L (copper concentration)- 25% ammonia water (for pH adjustment) ... Appropriate amount ・ Ion-exchanged water ... The balance

Then, in the same manner as in Example 1A, copper plating was formed on the iron substrate to prepare a sample to be peeled. Then, using the above-mentioned stripping solution (Comparative Samples 4-1 to 4-5), a treatment bath having a bath temperature of 50 ° C. and a liquid amount of 200 mL was prepared. And
The above delaminating sample that had been subjected to electrolytic degreasing treatment (60 ° C., 1 minute) and water washing (room temperature, 1 minute) was immersed in a treatment bath to peel off the copper plating. The presence or absence of corrosion of the iron substrate in this peeling treatment was observed, and the time required until the copper plating was completely peeled off was measured. The results are shown in Table 20 below.

[0112]

[Table 20]

As shown in Table 20, the stripping solutions containing the copper (II) ammine complex having chlorine ion as a counter ion (Comparative Samples 4-1 to 4-5) required the time required for stripping copper plating. Although much shorter than the conventional stripping solution (solution containing ammonium persulfate) shown in Example 1A, all of them corroded the iron base material and could not be put to practical use. From this, it was clarified that when a chloride ion was used as a counter ion of the copper (II) ammine complex, ammonium hydrogencarbonate could not exert an action as an inhibitor for inhibiting corrosion of iron substrate.

[0114]

As described in detail above, according to the present invention, the stripping solution is an alkaline aqueous solution containing a copper (II) ammine complex and an inhibitor, and the copper (II) ammine complex is used as a counter ion for the iron base material. Since it has a highly corrosive acid anion against, the copper (II) ammine complex acts as an oxidizing agent to dissolve and strip the copper plating on the iron substrate, so the stripping rate of the copper plating is high, Further, since the inhibitor suppresses the corrosion of the iron base material by the counter ion constituting the copper (II) ammine complex, the corrosion of the iron base material can be suppressed to an extremely low level, and the copper plating can be stripped.

Continued front page    (72) Inventor Takashi Nozaki             2-3-3 Yoshino-cho, Saitama City, Saitama Prefecture             Meltex Co., Ltd. F-term (reference) 4K057 WA01 WB04 WB15 WE03 WE11                       WE21 WE23 WF06 WG03 WG04                       WG06 WN10

Claims (12)

[Claims] 1. An alkaline aqueous solution containing a copper (II) ammine complex and an inhibitor, wherein the copper (II) ammine complex has an anion of an acid highly corrosive to an iron substrate as a counter ion. Stripping solution for copper plating on iron. 2. The anion is a formate anion,
The copper plating stripper on an iron substrate according to claim 1, wherein the inhibitor is ammonium hydrogen carbonate. 3. The concentration of ammonium hydrogen carbonate is 40 g / L.
It is above, The copper plating stripper on the iron-based material according to claim 2. 4. The stripping solution for copper plating on an iron substrate according to claim 2, wherein the copper concentration is within the range of 10 to 120 g / L. 5. The copper plating stripping solution on the iron substrate according to claim 2, wherein the pH is 8.5 or more. 6. The anion is an anion of sulfuric acid,
The copper plating stripper according to claim 1, wherein the inhibitor is at least one of ammonium hydrogen carbonate, sodium carbonate, and sodium hydrogen carbonate. 7. The ammonium hydrogen carbonate concentration is 50 g / L.
It is above, The copper plating stripper on the iron-based material according to claim 6. 8. The stripping solution for copper plating on an iron substrate according to claim 6, wherein the sodium hydrogen carbonate concentration is 50 g / L or more. 9. The stripping solution for copper plating on an iron substrate according to claim 7, wherein the copper concentration is in the range of 10 to 100 g / L. 10. The stripping solution for copper plating on an iron substrate according to claim 6, wherein the sodium carbonate concentration is 30 g / L or more. 11. The stripping solution for copper plating on an iron substrate according to claim 10, wherein the copper concentration is in the range of 30 to 100 g / L. 12. The stripping solution for copper plating on an iron substrate according to claim 6, which has a pH of 8.5 or more.