JP2000256883A - Metal treating agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obviate the occurrence of unevenness and staining by drying without using a chlorine-base solvent and to prevent the oxidation of a metallic surface in preservation after drying by treating the metallic surface by using an aqueous solution containing a specific amine component and a cyclohexylamine compound respectively at specific retions. SOLUTION: The aqueous solution containing 10 to 10000 ppm, by weight, amine compound expressed by formula I (where R1, R2 and R3 are each hydrogen, a 1-7C alkyl group, a 2-7C alkenyl group, a 1-4C alkanol group, a cycloalkyl group) and 1 to 1000 ppm cyclohexylamine compound expressed by formula II (where R1 and R2 are each hydrogen, a 1-7C alkyl group, cyclohexyl group) is used as the metal treating agent. The amine component is preferably hydoxyl, N,N-diethylhydroxylamine, or the like, and the cyclohexylamine compound is preferably cyclohexylamine, N,N-dicyclohexylmethylamine, or the like. The metal treating agent is preferably dried without rinsing after treating the metal.

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. 9-5319 is disclosed.
No. 4 discloses a dry pretreatment agent containing a hydroxylamine compound. By using the treatment liquid, oxidation during the drying step is suppressed, and the metal surface is dried unevenly.
Good without stains.

[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 made intensive studies on the above-mentioned problems, and as a result, by treating an aqueous solution containing a hydroxylamine compound and a cyclohexylamine compound as a dry pretreatment agent, a certain amount of water was obtained. It has been found that even when drying is carried out with the particles adhered, it is possible to effectively prevent metal oxidation during the drying step, and also to prevent metal oxidation during storage after drying.

That is, the present invention provides (A) the following formula (1)
Amine compound represented by the formula: 10 to 10,000 weight pp
m, (B) a metal treating agent which is an aqueous solution containing 1 to 1,000 ppm by weight of a cyclohexylamine compound represented by the following formula (2).

[0009]

Embedded image (In the formula (1), R1, R2, and R3 are hydrogen, an alkyl group having 1 to 7 carbon atoms, an alkenyl group having 2 to 7 carbon atoms,
4 is an alkanol group 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 boiling point or decomposition temperature of the amine compound or cyclohexylamine compound used in the present invention is preferably 200 ° C. or less. Compounds having a boiling point or decomposition temperature exceeding 200 ° C. have a high effect of preventing metal oxidation, but the components of the drying pretreatment agent adhere to the dried metal surface, resulting in uneven drying,
At the same time, it becomes difficult to obtain a clean metal surface, causing stains. 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 amine compound of the present invention, hydroxylamine, O-methylhydroxylamine, O-ethylhydroxylamine, N-methylhydroxylamine,
N, N-dimethylhydroxylamine, N, O-dimethylhydroxylamine, N-ethylhydroxylamine, N, N-diethylhydroxylamine, N, O-diethylhydroxylamine, O, N, N-trimethylhydroxylamine, N- (2-methoxyethyl) hydroxylamine, N-allylhydroxylamine, N, O
-Diallylhydroxylamine, O-cyclohexyl-
N, N-dimethylhydroxylamine and the like.
Of these, hydroxylamine and N, N-diethylhydroxylamine 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 amine compound of the present invention is 10 to 1
0.000 ppm by weight. If it is less than 10 ppm, drying unevenness and spots may occur depending on the type, shape, water quality, drying method and the like of the metal. On the other hand, when the content exceeds 10,000 ppm by weight, it is unsuitable in terms of handleability, 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. Next, immersion treatment was performed at room temperature for 60 seconds using an aqueous solution containing 500 ppm of hydroxylamine and 50 ppm of cyclohexylamine, and
It was dried in a box-shaped drier at ℃.

Example 2 In Example 1, instead of using an aqueous solution containing hydroxylamine and cyclohexylamine, N, N-
The procedure was performed in the same manner as in Example 1 except that 1000 ppm of diethylhydroxylamine and 50 ppm of dicyclohexylamine were used.

Example 3 A test piece (iron-nickel alloy) was subjected to chemical polishing, deburring and brightening. Next, it was immersed in an aqueous solution containing 10,000 ppm of N-methylhydroxylamine and 200 ppm of N-methylcyclohexylamine at room temperature for 30 seconds, and dried in a box-shaped dryer at 100 ° C.

Example 4 In Example 3, N-methylhydroxylamine, N
Instead of using an aqueous solution containing -methylcyclohexylamine, N, N-dimethylhydroxylamine 50
00 ppm, N, N-dicyclohexylethylamine 5
The same operation as in Example 3 was performed except that 00 ppm was used.

Example 5 A test piece (brass) was subjected to chemical polishing, deburring and brightening treatment. Next, immersion treatment was performed at room temperature for 30 seconds with an aqueous solution containing 50 ppm of N-ethylhydroxylamine and 100 ppm of dicyclohexylamine. After this was drained by air blow, 10
It was dried in a box dryer at 0 ° C.

Example 6 The procedure of Example 5 was repeated, except that 10 ppm of hydroxylamine and 500 ppm of N, N-dicyclohexylethylamine were used instead of the aqueous solution containing N-ethylhydroxylamine and dicyclohexylamine. I went to.

Example 7 Instead of using the aqueous solution containing N-ethylhydroxylamine and dicyclohexylamine in Example 5, 100 ppm of N-allylhydroxylamine,
Example 5 was carried out in the same manner as in Example 5, except that 500 ppm of ethylcyclohexylethylamine was used.

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

Comparative Example 1-2 The pretreatment for drying in Example 1 was changed to
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 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 3 except that the pretreatment liquid for drying in Example 3 was not used at all.

Comparative Example 2-2 The same procedure as in Example 3 was carried out except that the pretreatment solution for drying in Example 3 was changed to an aqueous solution containing only 10,000 ppm of N-methylhydroxylamine.

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

Comparative Example 3-1 The procedure of Example 5 was repeated, except that the pretreatment solution for drying was not used at all.

Comparative Example 3-2 The same procedure as in Example 5 was carried out except that the pretreatment liquid for drying in Example 5 was changed to an aqueous solution containing only 50 ppm of N-ethylhydroxylamine.

Comparative Example 3-3 Dicyclohexylamine 10 was used as the pretreatment liquid for drying in Example 5.
Example 5 was carried out in the same manner as in Example 5, 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

Table 1 shows the above results.

[Table 1]

[0040]

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] (A) 10 to 10,000 ppm by weight of an amine compound represented by the following formula (1), (B) a cyclohexylamine compound represented by the following formula (2):
A metal treating agent which is an aqueous solution containing 1,000 ppm by weight. Embedded image (In the formula (1), R1, R2, and R3 are hydrogen, carbon number 1 to 7)
Alkyl group, alkenyl group having 2 to 7 carbon atoms, 1 carbon atom
To 4 alkanol groups or cycloalkyl groups. ) (In the formula (2), R1 and R2 are hydrogen, an alkyl group having 1 to 7 carbon atoms, or a cyclohexyl group.) 2. The metal treating agent according to claim 1, wherein the amine compound is hydroxylamine or N, N-diethylhydroxylamine. 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.