JP3417703B2 - Water-soluble cleaning agent for metal materials - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-soluble detergent for metallic materials suitable for removing oil stains adhering to the surface of metallic materials such as IC lead frames.

[0002]

2. Description of the Related Art On the surface of a metal material such as an IC lead frame, there is cutting oil attached during processing and oil stains such as rust preventive oil applied during storage. If such oil stains are not sufficiently washed and removed, the surface treatment such as plating applied to the surface of the metal material later is adversely affected. Conventionally, in order to remove such oil stains, CFC-based cleaning agents, 1,
Chlorine-based solvents such as 1,1-trichloroethane and trichloroethylene have been used (as a similar technique, Japanese Patent Application Laid-Open No. Hei 4)
-370197, Japanese Patent Application Laid-Open No. 5-271690).

[0003]

However, the CFC-based cleaning agent is said to be a causative agent of ozone layer depletion and its use in large quantities is restricted, and the chlorine-based solvent is toxic to the human body.

Therefore, as a non-toxic cleaning agent which does not have a bad influence on the environment, a cleaning agent using a carbon-based solvent such as limonene, pinene, diterpene or the like, or a cleaning agent to which a glycol ether compound is added is used. But
Although such a cleaning agent satisfies environmental and safety conditions, it is easily deteriorated during use and has a problem of durability, so it cannot be said to be sufficient as an industrial cleaning agent.

Further, the conventional cleaning agent has a non-neutral pH and may corrode the surface of the metal material. When the surface of the metal material is eroded, the surface of the metal material is altered,
Alternatively, the metal melted from the metal material may be accumulated in the cleaning liquid to reduce the cleaning effect.

The present invention has been made by paying attention to such a conventional technique, and is advantageous in terms of environment and safety, has a high cleaning effect, and provides a water-soluble cleaning agent for a metal material which does not corrode the metal material itself. It is provided.

[0007]

In order to achieve the above object, this water-soluble detergent for a metal material contains a lipolytic enzyme and a nonionic surfactant, and the enzyme: nonionic surfactant The ratio of the agents is 100: 1 to 1: 1000 and the pH is 6.5-10.

As the lipolytic enzyme, lipase of microbial source, lipase of milk source and lipase of pancreatic source are suitable.

The nonionic surfactant itself has an inherent cleaning action, and the nonionic surfactant exerts an activating action on the enzyme, so that excellent cleaning can be performed especially on oil stains of metal materials. Show power. Since the main components are enzymes and nonionic surfactants, there are no environmental or safety problems,
There is no odor. And since it contains the enzyme, the removed oil stain is decomposed and solubilized by the enzyme and is not accumulated in the detergent. Therefore, it has a longer life than a cleaning agent containing no enzyme.

Further, since the pH is around 6.5 to 10, it does not corrode the metallic material. Therefore, the surface of the metal material is not altered and the metal component of the metal material does not dissolve in the cleaning agent. For example, aluminum, zinc, tin, lead, etc. which are eroded in the alkaline region are not eroded. Also,
Brass and copper, which cause discoloration in the alkaline region, also do not discolor.
Further, it can be applied to steel and the like which are easily eroded in the acidic region.

As the nonionic surfactant, a polyethylene glycol type is particularly preferable, and among them, a polymer of ethylene oxide, propylene oxide or butylene oxide is preferably used.

The ratio of enzyme to nonionic surfactant is 10
It should be between 0: 1 and 1: 1000. If the ratio of the enzyme to the nonionic surfactant is less than 1: 1000, the action of the enzyme on oil stain is significantly reduced, and if it is more than 100: 1, the cleaning action originally possessed by the nonionic surfactant Is reduced.

A buffer may be added to keep the pH near neutral. As the buffer, borate, phosphate, carbonate, ammonia, ammonia compound and the like are suitable.
The ratio of addition is 0.1 to 40 wt%. 0.1 wt
If it is less than 40% by weight, the buffering effect is lowered, and even if it is added in excess of 40% by weight, a higher effect cannot be obtained.

Although the erosion of the metal material by the cleaning agent can be suppressed as described above, some metals may erode even though the amount is very small. Therefore, if a chelating agent is added to the cleaning agent and the chelating agent captures a trace amount of the metal component dissolved in the cleaning agent, it is possible to prevent the dissolved metal component from adversely affecting the activation action of the enzyme. You can As the chelating agent, a carboxylic acid selected from the group of citric acid, gluconic acid, tartaric acid, lactic acid, glycolic acid or a salt thereof, ethylenediaminetetramine acetate, diethylenetriaminepentaacetic acid, nitriloacetate and the like are preferable. The ratio of addition is 0.1 to 40 wt%. This is because if the amount is less than 0.1 wt%, the chelating effect is lowered, and even if the amount is added more than 40 wt%, a higher effect cannot be obtained.

The temperature of the detergent is preferably in the range of room temperature to 60 ° C.

[0016]

EXAMPLES Example No. 1 in Table 1 below. 1 to 8, Comparative Example N
o. A cleaning agent having a composition such as 1 to 3 was prepared, and the IC lead frame was cleaned at room temperature using the cleaning agent. The nonionic surfactant used in the examples is ethylene oxide and the lipolytic enzyme is lipase of microbial source.
The buffer was phosphate and citric acid was used as the chelating agent.

As a comparative example, the hydrocarbon solvent was diterpene and the glycol ether solvent was polyoxyethylene alkyl ether.

[0018]

[Table 1]

As a cleaning method, first, the above cleaning agent was stored in an immersion tank, the cleaning agent was stirred in the tank, and the IC lead frame was immersed in the cleaning tank. And
After dipping in a dipping tank for 1 minute in a stationary state, it was taken out, washed with pure water, and dried.

Then, the island portion of the thus cleaned IC lead frame was plated with silver having a thickness of 5 μm by a known spray plating apparatus, and the cleaning condition was evaluated by the adhesion of the silver plating film. That is, if dirt such as oil and fat is left on the surface of the IC lead frame, the adhesion of the silver plating is deteriorated depending on the degree of dirt. Also, when the surface of the IC lead frame is altered by the cleaning agent, the adhesion of the silver plating is reduced. In addition, after the heat resistance test (450 ° C., 5 minutes), the adhesion of silver plating was judged by I
The surface was observed with a C inspection microscope.

As shown in Table 1, the results are shown in Table 1.
All of 1 to 8 have excellent adhesion of silver plating,
A good cleaning evaluation of "Very good" was shown. The cleaning evaluation was also "good".

On the other hand, Comparative Example No. 1 containing no enzyme.
The adhesion of the silver platings 1 to 3 was “slightly good Δ”.
Regarding the cleaning evaluation, No. Nos. 1 and 2 indicate “good ◯”, and No. 3 was “slightly good Δ”.

Further, in Example No. 3 in which a chelating agent was added.
Nos. 5 to 8 have a long life of the cleaning agent, and the number of IC lead frames which can be cleaned by the cleaning agent stored in the immersion tank is No. More than one to four. That is, when the IC lead frame was washed until the cleaning effect was lowered, the example No. More ICs with 5-8 cleaners
It was found that the lead frame could be cleaned. It is considered that this is because the chelating agent captured a trace amount of the metal component dissolved in the detergent and did not adversely affect the activation action of the enzyme itself.

[0024]

The water-soluble detergent for metallic materials according to the present invention has the contents as described above, does not adversely affect the environment, and is non-toxic, so that it is easy to handle. Moreover, a sufficient cleaning effect can be obtained without eroding the metal material.

Front page continued (51) Int.Cl. ⁷ identification code FI C11D 3: 386) (58) Fields investigated (Int.Cl. ⁷ , DB name) C23G 5/036 C11D 10/02 C11D 1:66 C11D 7 : 42 C11D 3: 386

Claims (5)

(57) [Claims] 1. A lipolytic enzyme and a nonionic surfactant are contained, and the ratio of enzyme: nonionic surfactant is 100:
A water-soluble detergent for a metal material, which has a pH of 1 to 1: 1000 and a pH of 6.5 to 10. 2. The water-soluble detergent for metal materials according to claim 1, wherein the lipolytic enzyme is one or more selected from the group consisting of lipases of microbial source, lipases of milk source, and lipases of pancreatic source. 3. A pH selected from the group of borate, phosphate, carbonate, ammonia, and ammonia compound is 6.5 to 5.
0.1 to 40 w of one or more buffers that can be adjusted to 10
The water-soluble detergent for metal materials according to claim 1 or 2, which is added in a proportion of t%. 4. Citric acid, gluconic acid, tartaric acid, lactic acid,
The metal material according to any one of claims 1 to 3, wherein one or more chelating agents consisting of a carboxylic acid selected from the group of glycolic acid or a salt thereof is added in a proportion of 0.1 to 40 wt%. Water-soluble cleaning agent. 5. The method according to claim 1, wherein one or more chelating agents selected from the group consisting of ethylenediaminetetramine acetate, diethylenetriaminepentaacetic acid and nitriloacetate are added in a proportion of 0.1 to 40 wt%. A water-soluble detergent for a metal material according to item 1.