JP2002030473A - Discoloration preventive agent for alloy, composition of aqueous cleaning agent, rinsing agent, aqueous cleaning method and water rinsing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a discoloration preventive agent for alloys used for cleaning optical parts, electronic parts, metallic parts or ceramic parts mounted with parts made of an alloy or the simple substance of the parts made of an alloy or water rinsing therefor, further to provide an aqueous cleaning agent and a rinsing agent containing the same discoloration preventive agent, moreover to provide a cleaning method for alloys using the same aqueous cleaning agent and to provide a water rinsing method using the same rinsing agent. SOLUTION: This discoloration preventive for alloys is composed of at least one carbonate expressed by the general formula (1): MaHb(CO3)n (wherein, (a) is an integer of 1 or 2; (b) is an integer of 0 to 2; (n) is a metallic atom or a volatile organic base having ionization tendency higher than that of magnesium; and H is hydrogen) and at least one kind of nitrogen-based heterocyclic compound, and the weight ratio of the carbonate/the nitrogen-based heterocyclic compound is 0.001 to 10,000.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discoloration inhibitor used for a specific alloy, particularly an alloy containing copper as an essential metal component (for example, nickel silver and nickel alloy). More specifically, a discoloration preventing agent used when an optical component, an electronic component, a metal component, a ceramic component, or a single alloy component mounted with an alloy component is subjected to water-based washing or water rinsing after washing; A water-based cleaning composition comprising: a rinsing agent containing the discoloration inhibitor; an aqueous cleaning method for an alloy using the cleaning composition; and an alloy rinsing using a rinsing agent containing the discoloration inhibitor. .

[0002]

2. Description of the Related Art Conventionally, when cleaning various electronic parts and individual parts made of alloys, a chlorine-based cleaning agent mainly containing a chlorine-based solvent such as trichloroethylene, perchlorethylene or methylene chloride has been used. While these chlorine-based solvents have the advantage of being nonflammable and excellent in drying properties, their use is currently restricted from the viewpoints of environmental problems such as ozone layer destruction and soil pollution, and toxicity to human bodies. Further, in cleaning electronic parts and the like, there is a problem that the cleaning effect by the chlorine-based solvent is hardly recognized with respect to ionic residues such as chloride ions and sulfate ions, which are particularly important in recent years.

On the other hand, water-based cleaning agents satisfy required performances such as environmental characteristics, odor and flammability, and are also excellent in cleaning performance against ionic residues. It has begun to be awarded for cleaning precision parts such as.

However, an optical component, an electronic component, a metal component, a ceramic component, or a single component made of an alloy having a component made of an alloy containing copper as an essential metal component, such as nickel silver, is washed with a water-based cleaning agent. After that, when rinsing with water, there is a disadvantage that the surface of the alloy is significantly discolored and the appearance and quality of the product are deteriorated. For example, taking an example of nickel white as an alloy, when nickel white comes into contact with water, it constitutes silver 3.
Among the species of metals (ie, copper, nickel and zinc), nickel and zinc, which have a high ionization tendency, are preferentially eluted into water, and copper, which has a low ionization tendency, remains relatively more on the surface of nickel silver. In addition, the copper is oxidized by water or air, so that the surface of the nickel white is turned reddish brown. When a conventional water-based cleaning agent or water-based rinsing agent is used, it has been practically difficult to suppress the elution of nickel and zinc into water and at the same time prevent the oxidation of copper. Therefore, with respect to optical components, electronic components, metal components, ceramic components or components made of nickel silver, which are equipped with nickel silver components, cleaning with a chlorine solvent is still carried out while knowing the above-mentioned disadvantages of chlorine solvents. Has been done.

[0005]

SUMMARY OF THE INVENTION The present invention relates to an optical component, an electronic component, a metal component, a ceramic component, or a single component made of an alloy, mounted with an alloy component typified by nickel silver, which is washed with an aqueous cleaning agent. Another object of the present invention is to provide an additive for preventing discoloration of an alloy during water rinsing. Another object of the present invention is to provide a water-based cleaning agent and a rinsing agent containing the discoloration inhibitor, a method for cleaning an alloy using the water-based cleaning agent, and a method for water rinsing.

[0006]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, simultaneously added a specific carbonate and a nitrogen-based heterocyclic compound to an aqueous detergent and rinse water. By doing so, it has been found that discoloration of the alloy can be prevented. The present invention has been completed based on such findings.

That is, the present invention provides a compound represented by the general formula (1): M _a
H _{b (CO 3) n}

Wherein a is 1 or 2, b is an integer of 0 to 2, n is 1 or 2, M is a metal atom or a volatile organic base having a higher ionization tendency than magnesium, and H is a hydrogen atom. At least one of the carbonates represented by
A discoloration inhibitor for an alloy, comprising at least one of a seed and a nitrogen-based heterocyclic compound, wherein the weight ratio of carbonate / nitrogen-based heterocyclic compound is 0.001 to 10,000. . The present invention also relates to an aqueous detergent composition and a rinsing agent containing the discoloration inhibitor for the alloy. Further, the present invention provides a water-based cleaning method for cleaning an electronic component or the like or an alloy component carrier mounted with an alloy component using the water-based cleaning composition, and an electronic component mounted with an alloy component using the rinse agent. The present invention relates to a water rinsing method for an alloy, which comprises rinsing a part or the like or an alloy part carrier with water.

BEST MODE FOR CARRYING OUT THE INVENTION

The discoloration inhibitor of the present invention has the general formula (1)
It is characterized by being able to exhibit an excellent discoloration preventing effect on the alloy by using both a specific carbonate represented by and a nitrogen-based heterocyclic compound, and using a very small amount of the discoloration inhibitor. .

Hereinafter, for the sake of convenience of explanation of the present invention, a description will be given taking nickel silver as a representative of the alloy. When dissolved in water, the carbonate represented by the general formula (1) dissociates into metal ions and carbonate ions or hydrogen carbonate ions. The carbonate ion or hydrogen carbonate ion reacts with nickel and zinc present on the nickel-white surface to become nickel carbonate, nickel hydrogen carbonate, zinc carbonate or zinc hydrogen carbonate, respectively, and becomes a stable insoluble substance in water. Thereby, the elution of nickel and zinc from the surface of the nickel silver is suppressed, and the original color tone (silver white) of nickel silver can be maintained. In addition, with respect to copper present on the surface of nickel silver, the oxidation of copper can be suppressed by the chelation bond between the nitrogen atom of the nitrogen-based heterocyclic compound and the copper, thereby discoloring due to the copper oxide. Can also be suppressed. As described above, the discoloration inhibitor for the alloy of the present invention can suppress the elution of nickel or zinc having a large ionization tendency and, at the same time, can prevent the oxidation of copper having a small ionization tendency. The effect is very good.

In the general formula (1), specific examples of the metal atom M include alkali metals such as sodium and potassium;
Magnesium, metals such as alkaline earth metals such as calcium have a higher ionization tendency than magnesium, and volatile organic bases include, for example, ammonia, monomethylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine, triethylamine and the like. However, the present invention is not limited only to such an example. One selected from these metals or organic bases can be used alone or in combination of two or more. Among the carbonates represented by the general formula (1), ammonium carbonate and ammonium hydrogencarbonate are most preferable from the viewpoint that there is no fear of remaining due to decomposition and volatilization in the drying step.

Specific examples of the nitrogen-based heterocyclic compound include benzotriazole, 1-methylbenzotriazole,
1-hydroxymethylbenzotriazole, 1-((2
Benzotriazole derivatives such as -ethylhexylamino) methyl) benzotriazole, 1- (2,3-dihydroxypropyl) benzotriazole and carboxybenzotriazole. These can be used alone or in combination of two or more.
Among the benzotriazole derivatives, benzotriazole is preferred from the viewpoint of the effect of preventing discoloration.

The combined ratio of carbonate and nitrogen-based heterocyclic compound (weight ratio of carbonate / nitrogen-based heterocyclic compound) is 0.00
1 to 10,000, preferably 0.1 to 1,000.
0. If the ratio is out of the range of 0.001 to 10,000, not only is there no discoloration preventing effect, but also abnormal discoloration may occur.

By dissolving the discoloration inhibitor of the present invention in water,
A rinse agent can be easily prepared. When the discoloration inhibitor is mixed with a known aqueous detergent, the aqueous detergent composition of the present invention can be easily prepared. The content of the discoloration inhibitor in the rinsing agent or the aqueous detergent composition is not particularly limited, and may be appropriately selected depending on use conditions, but is usually 0.0%.
001 to 1% by weight, preferably 0.001 to 0.1% by weight.

In order for the rinsing agent and the aqueous detergent composition of the present invention to exhibit the desired discoloration preventing effect, the content of the rinsing agent and the aqueous detergent composition in the aqueous detergent composition is as described above. Where carbonate is usually 0.0
The content is from 001% by weight to 1% by weight, and the content of the nitrogen-based heterocyclic compound is usually from 0.00001% by weight to 0.1% by weight. More preferably, the carbonate is 0.0
The content is from 01% by weight to 0.1% by weight, and the content of the nitrogen-based heterocyclic compound is from 0.0001% by weight to 0.01% by weight.

Next, the aqueous cleaning method and the water rinsing method of the present invention will be described. As a water-based cleaning method for a nickel-white component alone or a nickel-white product mounted component, a water-based cleaning composition containing a predetermined amount of the discoloration inhibitor described above, or a cleaning step using a normal water-based cleaning agent is used. Do. Subsequently, rinsing is performed using a rinsing agent containing the above-described discoloration inhibitor, and further, finish rinsing is appropriately performed according to the cleanliness required for the product, and finally, the object to be cleaned may be dried. The discoloration inhibitor of the present invention may be used in a step where discoloration usually occurs in aqueous washing. For example, when washing is performed using a detergent having a low water content, the discoloration inhibitor is not necessarily used in the washing step, but is desirably used in the next rinsing step. When a detergent having a high water content is used, it is desirable to use a discoloration inhibitor from the washing step, but the present invention is not limited to this example.

Examples of the above-mentioned known aqueous detergent include an alkaline detergent, a glycol ether detergent, an alcohol detergent, a surfactant detergent, and the like. These may be used alone or in combination of two or more. However, the present invention is not limited to such an example.

The water includes city water, ion-exchanged water, pure water, and the like, but the present invention is not limited to such examples.

The method of washing and rinsing an object to be washed using the aqueous detergent composition containing the discoloration inhibitor of the present invention and the rinsing agent includes immersion, immersion vibration, immersion ultrasonic wave,
There are various cleaning methods such as a liquid spray, an air spray, a barrel, and a direct type, but the present invention is not limited to only such examples.

After washing and rinsing using the aqueous detergent composition containing the discoloration inhibitor of the present invention and a rinsing agent,
Perform drying. Examples of the drying method include hot air drying. Preferably, a direct drying method is used in which a large amount of air is used to drain the water and a large amount of hot air is used for drying (for example, product name “Direct Pass”, Arakawa Chemical Co., Ltd.). (Manufactured by Kogyo Co., Ltd.) is preferred, but the present invention is not limited to such examples.

[0021]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Comparative Examples and Examples, but the present invention is not limited to these Examples.

Examples 1 to 10 and Comparative Example 1 A nickel white cover part of a VCO (voltage controlled oscillator) (8.5)
mm × 6.0 mm) was previously subjected to ultrasonic cleaning for 5 minutes using a glycol ether-based detergent (trade name “Pine Alpha ST-100SX”, manufactured by Arakawa Chemical Industries, Ltd.). Then, various rinsing agents 1 shown in Tables 1 and 2
Each was rinsed with ultrasonic waves for 5 minutes using 00 ml, and further rinsed with ultrasonic waves for 5 minutes using 10 ml of ultrapure water. After completion of the drying step, the surface condition of the nickel-white parts was visually checked, and the amount of zinc and nickel atoms eluted in the finishing rinse was measured. The results are shown in Tables 3 and 4.

An atomic absorption spectrometer was used to measure the amount of zinc and nickel dissolved in the finishing rinse agent.

[0024]

Table 1 Units in Table 1 indicate% by weight.

[0025]

Table 2 Units in Table 2 indicate% by weight.

[0026]

[Table 3] The unit of the elution amount in Table 3 is nanogram (ng).

[0027]

[Table 4] The unit of the elution amount in Table 4 indicates nanogram (ng).

In Examples 1 to 10, the elution amounts of both nickel and zinc were small, and there was no discoloration on the component surface. On the other hand, in Comparative Example 1, the amounts of nickel and zinc eluted were large, and the surface of the component turned from silver white to yellow.

[0029]

As described above, the discoloration inhibitor for alloys of the present invention, and the rinsing agent and water-based detergent composition containing the discoloration inhibitor, can be used for an electronic component or the like on which an alloy component is mounted, or an alloy component. It is possible to effectively prevent discoloration that occurs when the component carrier is washed or rinsed with water. In particular, the present invention is useful for alloys containing copper as an essential component (for example, nickel silver). Similarly, the water-based cleaning method and the water rinsing method of the present invention also have the above-described effect of preventing discoloration.

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Claims (14)

[Claims] 1. Formula (1): M_aH_b(CO₃)_n  (Where a is 1 or 2, b is an integer of 0 to 2, n is 1 or
2, M is a metal with a greater ionization tendency than magnesium
An atom or a volatile organic base, H is a hydrogen atom,
At least one carbonate represented by the formula:
At least one heterocyclic compound, and carbonic acid
Salt / nitrogen heterocyclic compound (weight ratio) is 0.001 to 1
An anti-tarnish agent for an alloy, wherein the anti-tarnish agent is 000. 2. The discoloration inhibitor according to claim 1, wherein M in the general formula (1) is an alkali metal atom or an alkaline earth metal atom. 3. M in the general formula (1) is a volatile organic base, and the volatile organic base is selected from the group consisting of ammonia, monomethylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine and triethylamine. The discoloration inhibitor according to claim 1, which is at least one kind. 4. The discoloration inhibitor according to claim 1, wherein the nitrogen-based heterocyclic compound is a benzotriazole derivative. 5. The alloy applied is copper, zinc, nickel,
The discoloration inhibitor according to any one of claims 1 to 4, comprising at least two kinds of metal atoms selected from the group consisting of iron, tin, lead, magnesium and aluminum. 6. The discoloration inhibitor according to claim 5, wherein the applied alloy contains copper as an essential metal component. 7. The anti-tarnish agent according to claim 6, wherein the applied alloy is nickel silver composed of copper, zinc and nickel. 8. The anti-tarnish agent according to claim 1, wherein the weight ratio of carbonate / nitrogen heterocyclic compound in the anti-tarnish agent is 0.1 to 1,000. 9. An aqueous cleaning composition comprising the discoloration inhibitor according to claim 1. Description: 10. The content of the discoloration inhibitor is 0.000.
The aqueous detergent composition according to claim 9, which is 1 to 1% by weight. 11. A rinsing agent comprising the discoloration inhibitor according to claim 1. 12. The content of the discoloration inhibitor is 0.000.
The rinsing agent according to claim 11, which is 1 to 1% by weight. 13. A method for aqueous cleaning of an alloy, comprising washing an electronic component or the like or an alloy component carrier on which an alloy component is mounted, using the aqueous detergent composition according to claim 9 or 10. 14. A water rinsing method for an alloy, wherein the rinsing agent according to claim 11 or 12 is used to rinse an electronic component or the like or an alloy component carrier on which the alloy component is mounted.