JP2000248296A - Metal treating agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a metal treating agent preventing the generation of unevenness and spot even by drying a metal having water drops and suppressing the oxidation of the metal surface without using a chlorine-based solvent by including respectively specific hydrazine compound and cyclohexylamine compound at a specific ratio. SOLUTION: The objective agent is an aqueous solution containing (A) 10-10,000 wt.ppm of a hydrazine compound of formula I (R1 to R4 are each H, a 1-7C alkyl, a 1-4C alkanol, or the like) such as hydrazine, methylhydrazine and ethylhydrazine and (B) 1-1,000 wt.ppm of a cyclohexylamine compound of formula II (R1 and R2 are each H, a 1-7C alkyl or cyclohexyl) such as cyclohexylamine, dicylcohexylamine and N,N-dicyclohexylmethylamine. A metal is treated preferably by treating with a metal surface treating agent or a metal cleaning agent, and then treating with the above metal treating agent and the treated metal without washing with water.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a treating agent which prevents unevenness and spots due to a drying step and suppresses oxidation of a metal surface even after storage after drying in the field of aqueous metal surface treatment and metal cleaning. It is about.

[0002]

2. Description of the Related Art Conventionally, in the field of water-based metal surface treatment and metal cleaning, as a method for preventing metal oxidation in a drying step for preventing drying unevenness and spots, a draining substitution method using a solvent, a vacuum drying method, a nitrogen drying method, and the like. Drying in an atmosphere. However, the vacuum drying method requires high equipment costs,
Work efficiency is also low. Drying in a nitrogen atmosphere is also expensive in terms of equipment costs, and the cost is high because a large amount of nitrogen is used. These drying methods are applied to special products, and are generally drained with a solvent. Substitution methods are employed industrially.

[0003] In many cases, drying when water is adhered,
Discoloration due to oxidation of the metal surface occurs, reducing product value.
For this reason, in the draining replacement method using a solvent, after rinsing (final finish) water washing, treatment with Freon or a chlorine-based solvent is performed to replace and remove water on the metal surface. However, since the used fluorocarbon or chlorinated solvent causes environmental destruction, their use has been regulated worldwide, and there is a strong demand for alternative technologies.

As an alternative technique, Japanese Patent Laid-Open No. 9-3678 is disclosed.
Discloses a pretreatment agent for drying containing a hydrazine compound. By using the treatment liquid, oxidation during the drying step is suppressed, and the metal surface becomes excellent without drying unevenness and spots.

[0005] The fact that cyclohexylamine compounds have a rust-preventing effect is disclosed in "Practical use of vaporizable rust-preventing agents" (published by Tadashi Hori (published by the Japan Rust Prevention Technology Association)). However, when used only as a rust inhibitor, the concentration used is as high as 0.5 to 5% by weight, so if it is dried without rinsing after treatment, evaporation residues of the cyclohexylamine compound are generated on the metal surface, It causes drying unevenness and spots.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to prevent the occurrence of unevenness and spots even when water is adhered and dried without using a chlorine-based solvent which causes environmental destruction, and at the same time, to prevent the occurrence of environmental problems. An object of the present invention is to provide a metal treating agent which prevents oxidation of a metal surface even during storage.

[0007]

Means for Solving the Problems The present inventors have conducted intensive studies on the above problems, and as a result, by treating an aqueous solution containing a hydrazine compound and a cyclohexylamine compound as a drying pretreatment agent, a certain amount of water was obtained. The present inventors have found that even when dried while being adhered, it is possible to effectively prevent metal oxidation during the drying step, and to prevent metal oxidation during storage after drying.

That is, the present invention relates to (A) 10 to 10,000 ppm by weight of a hydrazine compound represented by the following formula (1), and (B) 1 to 1,000 wt.% Of a cyclohexylamine compound represented by the following formula (2). The present invention relates to a metal treating agent which is an aqueous solution containing ppm.

[0009]

Embedded image (In the formula (1), R1, R2, R3, and R4 are hydrogen, carbon number 1)
Or an alkenyl group having 2 to 7 carbon atoms, an alkanol group having 1 to 4 carbon atoms, or a cycloalkyl group. )

[0010]

Embedded image (In the formula (2), R1 and R2 are hydrogen, an alkyl group having 1 to 7 carbon atoms, or a cyclohexyl group.)

[0011]

DETAILED DESCRIPTION OF THE INVENTION The present invention is directed to grinding, cutting, die casting, and sintering of iron, copper, nickel, chromium, cobalt, lead, zinc, aluminum, titanium, tin, gold and silver, and alloys thereof. You can adapt to what you do. Further, the present invention can also be applied to products metallized on the surface of resin, glass, ceramics, and the like by means such as adhesion, pressure bonding, plating, vapor deposition, and ion plating.

The aqueous metal surface treatment process used in the present invention includes electroless plating, electroplating, anodic oxidation,
Pickling, alkali cleaning, chemical polishing, electrolytic polishing, mechanical polishing, metal coloring, etching, chemical conversion, and other processes are included. Examples of aqueous metal cleaning processes include degreasing, acid cleaning,
Processes such as alkali cleaning and electrolytic cleaning are exemplified.

In these various metal surface treatments and metal cleaning processes, after rinsing water, the metal is treated with an aqueous solution containing a drying pretreatment agent prior to drying, or a drying pretreatment agent is added to the rinsing water. After the treatment which also serves as washing with the aqueous solution, the metal is dried.

The hydrazine compound and cyclohexylamine compound used in the present invention have a boiling point or decomposition temperature of 200.
It is preferable that it is below ° C. 200 boiling point or decomposition temperature
Compounds exceeding ℃ are highly effective in preventing metal oxidation, but the components of the pre-drying agent adhere to the dried metal surface, causing drying unevenness and spots, and at the same time it is difficult to obtain a clean metal surface. . If the drying temperature is increased, this defect can be prevented, but it is not preferable from the viewpoint of handleability and economy.

As the hydrazine compound of the present invention, 1,1
-Diethylhydrazine, 1,2-diethylhydrazine,
Methylhydrazine, ethylhydrazine, 1,1-dimethylhydrazine, 1,2-dimethylhydrazine, 1,2-
Examples thereof include diisopropyl hydrazine, hydrazine, cyclohexyl hydrazine, allyl hydrazine, and isopropyl hydrazine. Of these, hydrazine, methylhydrazine, 1,1-dimethylhydrazine, 1,2-
Dimethylhydrazine, ethylhydrazine, 1,1-diethylhydrazine, and 1,2-diethylhydrazine are preferred.

Examples of the cyclohexylamine compound of the present invention include cyclohexylamine, N-methylcyclohexylamine, N-ethylcyclohexylamine, dicyclohexylamine, N, N-dicyclohexylmethylamine, N, N-dicyclohexylethylamine and the like.

The concentration of the hydrazine compound of the present invention is 10
-10,000 ppm by weight. If it is less than 10 ppm, depending on the type, shape, water quality, drying method, etc. of the metal,
Dry unevenness and spots may occur. Also, 10,000
If it exceeds 0 ppm by weight, it is unsuitable for handling properties, economy and the like.

The concentration of the cyclohexylamine compound of the present invention is 1 to 1,000 ppm by weight, preferably 1 to 1,000 ppm.
0 to 1,000 ppm by weight, more preferably 10
５００500 ppm by weight. When the concentration is less than 1 ppm by weight, almost no antioxidant effect is observed,
If the content exceeds ppm, evaporation residues may be generated after drying.

The time for the pre-drying treatment varies depending on the type, shape, treatment method and the like of the metal, and is not particularly limited. However, practically, 10 to 600 seconds is preferable. If less than 10 seconds,
Dry unevenness and spots may occur on the product. Even if it exceeds 600 seconds, there is no problem in the processing effect itself, but it is inappropriate from the viewpoint of productivity and economy. The treatment temperature is not particularly limited, but is preferably room temperature or higher. In order to increase the drying efficiency, there is no problem in the processing effect even if the water is washed at 80 ° C or higher.
Rather, there is an advantage that a metal having an excellent appearance can be obtained.

[0020]

EXAMPLES The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited to the following examples.

Example 1 A bearing component (made of SS400) was chemically polished, deburred and brightened, and then washed with water. Then, hydrazine 500
An immersion treatment was performed at room temperature for 60 seconds using an aqueous solution containing 50 ppm of cyclohexylamine and 50 ppm of cyclohexylamine, followed by drying in a box dryer at 80 ° C.

Example 2 In Example 1, instead of using an aqueous solution containing hydrazine and cyclohexylamine, 1000 ppm of methylhydrazine and 50 parts of N-methylcyclohexylamine were used.
The same operation as in Example 1 was performed except that ppm was used.

Example 3 Instead of using an aqueous solution containing hydrazine and cyclohexylamine in Example 1, 1000 ppm of 1,1-dimethylhydrazine and 5 parts of dicyclohexylamine were used.
The same operation as in Example 1 was performed except that 0 ppm was used.

Example 4 A test piece (iron-nickel alloy) was chemically polished, deburred and brightened. Next, it was immersed in an aqueous solution containing 10,000 ppm of ethylhydrazine and 200 ppm of N, N-dicyclohexylmethylamine at room temperature for 30 seconds, and dried with a box-shaped dryer at 100 ° C.

Example 5 In Example 4, instead of using an aqueous solution containing ethylhydrazine and N, N-dicyclohexylmethylamine, 5000 ppm of 1,2-dimethylhydrazine was used.
The procedure was performed in the same manner as in Example 4 except that 500 ppm of N, N-dicyclohexylethylamine was used.

Example 6 In Example 4, instead of using an aqueous solution containing ethylhydrazine and N, N-dicyclohexylmethylamine, 5000 ppm of 1,2-diethylhydrazine was used.
The procedure was performed in the same manner as in Example 4 except that 100 ppm of N, N-dicyclohexylethylamine was used.

Example 7 In Example 4, instead of using an aqueous solution containing ethyl hydrazine and N, N-dicyclohexylmethylamine, 5000 pp of 1,2-diisopropylhydrazine was used.
The procedure was performed in the same manner as in Example 4, except that 100 ppm of m, N-methylcyclohexylamine was used.

Example 8 A test piece (brass) was chemically polished, deburred and brightened. Then, at room temperature, 1,1-diethylhydrazine 5
The immersion treatment was performed for 30 seconds with an aqueous solution containing 0 ppm and 100 ppm of dicyclohexylamine. After the solution was drained by air blow, 100
It dried with the box-shaped dryer of ° C.

Example 9 The procedure of Example 8 was repeated, except that 50 ppm of cyclohexylhydrazine and 100 ppm of N-ethylcyclohexylamine were used instead of using an aqueous solution containing 1,1-diethylhydrazine and dicyclohexylamine. I went to.

Comparative Example 1-1 Example 1 was repeated except that no drying pretreatment was performed.
The same was done.

Comparative Example 1-2 The same procedure as in Example 1 was carried out except that the pretreatment for drying in Example 1 was performed using an aqueous solution containing only 500 ppm of hydrazine.

Comparative Example 1-3 The drying pretreatment of Example 1 was performed using cyclohexylamine at 50 pp.
The procedure was performed in the same manner as in Example 1 except that the procedure was performed using an aqueous solution containing only m.

Comparative Example 2-1 The same procedure was performed as in Example 4 except that the pretreatment liquid for drying in Example 4 was not used at all.

Comparative Example 2-2 The dry pretreatment liquid of Example 4 was replaced with ethyl hydrazine 10,000
The procedure was performed in the same manner as in Example 4 except that the procedure was performed with an aqueous solution containing only 0 ppm.

Comparative Example 2-3 The same procedure as in Example 4 was carried out except that the pretreatment solution for drying in Example 4 was changed to an aqueous solution containing only 200 ppm of N, N-dicyclohexylmethylamine.

Comparative Example 3-1 The procedure of Example 7 was repeated, except that the drying pretreatment liquid of Example 7 was not used at all.

Comparative Example 3-2 Example 7 was repeated except that the pretreatment liquid for drying in Example 7 was used in an aqueous solution containing only 50 ppm of 1,1-diethylhydrazine.
The same was done.

Comparative Example 3-3 Dicyclohexylamine 10 was used as the pretreatment liquid for drying in Example 7.
Example 7 was carried out in the same manner as in Example 7, except that an aqueous solution containing only 0 ppm was used.

The metal product after each of the above treatments is visually observed,
The appearance such as drying unevenness and spots was evaluated on a 4-point scale based on the following criteria. ◎: Excellent appearance without defects such as drying unevenness or spots. ：: Very few defects in appearance such as drying unevenness or spots. ：: Slight appearance defects such as drying unevenness or spots. Inferior. ×: Inferior appearance defects such as drying unevenness and stains are inconspicuous.

Further, the metal product after each of the above treatments was
It was stored for 24 hours under the conditions of 0 ° C. and 90% RH, and the rusting state was evaluated in four stages. ：: no rusting ○: rusting area 1 to less than 5% △: rusting area 5 to less than 20% ×: rusting area 20% or more

The results are shown in Table 1.

[Table 1]

[0042]

By using the treating agent of the present invention as a pre-drying treating agent, it is possible to suppress the occurrence of uneven drying and stains on the metal surface even if the treating agent is not rinsed after the treatment and dried with the liquid attached. Therefore, the appearance becomes good. Furthermore, even after storage after drying, it is possible to suppress oxidation of the metal surface, so that a good appearance can be maintained.

Claims (4)

[Claims] 1. A hydrazine compound represented by the following formula (1): 10 to 10,000 ppm by weight, and (B) a cyclohexylamine compound represented by the following formula (2): 1 to 1,000 ppm by weight. A metal treatment agent that is an aqueous solution. Embedded image (In the formula (1), R1, R2, R3, and R4 are hydrogen, carbon number 1)
Or an alkenyl group having 2 to 7 carbon atoms, an alkanol group having 1 to 4 carbon atoms, or a cycloalkyl group. ) (In the formula (2), R1 and R2 are hydrogen, an alkyl group having 1 to 7 carbon atoms, or a cyclohexyl group.) 2. The method according to claim 1, wherein the hydrazine compound is hydrazine, methylhydrazine, ethylhydrazine, 1,1- or 1,2-.
The metal treating agent according to claim 1, which is dimethylhydrazine or 1,1- or 1,2-diethylhydrazine. 3. The metal treating agent according to claim 1, wherein the cyclohexylamine compound is cyclohexylamine, dicyclohexylamine, N, N-dicyclohexylmethylamine, or N, N-dicyclohexylethylamine. 4. A method for drying a metal, comprising: treating with a metal surface treating agent or a metal cleaning agent, followed by treating with the metal treating agent according to claim 1, and drying without washing with water.