JP2003126791A - Cleaning method and cleaning apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cleaning method and a cleaning apparatus in which such a problem is solved that ground water or city water to be supplied to a first rinsing tank or the like is reacted with a cleaning agent to produce an insoluble component and the insoluble component is accumulated in pipelines and tanks of the cleaning apparatus and contaminates an object to be cleaned. SOLUTION: The reaction of ground water or city water with the cleaning agent and the contamination of the cleaning apparatus and the object to be cleaned are prevented by supplying soft water to at least the first rinsing tank.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a cleaning method and a cleaning apparatus. More specifically, it relates to rinse water in the washing step.

[0002]

2. Description of the Related Art As countermeasures against ozone layer depletion and global warming, halogen-based organic solvents such as CFC are being replaced as cleaning agents. As alternative cleaning agents, hydrocarbons and water-based or semi-water-based cleaning agents have been widely used.

In a water-based or semi-water-based cleaning agent,
After cleaning with the cleaning agent, the cleaning agent adhering to the cleaning object must be removed (rinse). The water used for rinsing is often used in a large amount for efficient rinsing. Therefore, ground water (well water) and tap water (city water, town water, etc.) are used in the rinse step (first step) immediately after the cleaning agent.

[0004]

However, the properties of groundwater and tap water as described in the prior art differ depending on the region and season. It is considered that the characteristics depending on the region and the season do not change depending on the formation and the amount of water, and the substances (mainly ions) contained in the water are considered to change accordingly.

Among these substances, calcium (Ca)
Water containing a lot of magnesium (Mg) ions is called hard water. The amount of Ca and Mg ions is called hardness, and in the present invention, it is expressed by the value of American hardness (ppm).
The hardness of water can be generally investigated with a reagent called a hardness indicator. The hardness indicator is a liquid containing Eriochrome Black T, and exhibits a blue color at a hardness of 0 ppm, a purple color up to a hardness of 1.8 ppm, and a red color when the hardness exceeds this level.

[0006] The cleaning agent is composed of a mixture of several to several tens of substances including a surfactant and an alkaline component in order to wash various stains. Depending on the components, groundwater And tap water components, mainly components that react with metal ions such as calcium and magnesium, which are the standard of hardness, may be contained. The components that have reacted with the metal ions become water-insoluble components.

The reacted components cause recontamination of the object to be cleaned, resulting in poor cleaning.

On the other hand, the reacted components adhere to and accumulate in a tank, a tank, a pipe, etc. in the cleaning device, depriving the cleaning device of its function. In addition, since it is also contained in wastewater, it also adheres to wastewater piping, which is the infrastructure of factories, etc., and accumulation occurs, leading to serious effects on production functions such as drainage flow stoppage.

Further, the cleaning agent is mostly heated to improve the cleaning property. When the water contained in the cleaning agent evaporates in a heated state, it is necessary to replenish the water. If ground water or tap water is used to replenish the water, precipitates are similarly generated in the cleaning agent tank.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a cleaning method which does not generate deposits in the rinse tank.

Another object of the present invention is to provide a cleaning device which does not generate deposits in the rinse tank.

[0012]

In order to achieve the above object, the present inventor has conducted extensive studies and as a result, it is effective to eliminate the generation of precipitates by supplying soft water to the rinse tank after the washing step. I found that.

By using soft water, insoluble components are not generated in the cleaning agent tank and the rinse tank, and re-contamination of the object to be cleaned is eliminated.

There is no possibility of adhering to the inside of the cleaning agent tank and the rinse tank in the cleaning device and clogging the pipes and the like.
In addition, there is no accumulation of drainage on the piping, and there is no impact on the production function.

Therefore, the invention according to claim 1 provides a cleaning method having a rinse step with water, characterized in that soft water is used at least in the first step of the rinse step.

The invention according to claim 2 provides the cleaning method according to claim 1, wherein the soft water used has a hardness of 1.8 ppm or less.

The third aspect of the present invention provides a cleaning apparatus having a water rinsing step, which has a function of supplying soft water to at least the first step of the rinsing step.

The invention according to claim 4 is the cleaning device according to claim 3, characterized in that the soft water supplied has a hardness of 1.8 ppm or less.

The invention according to claim 5 provides the cleaning device according to claim 3 or 4, wherein the function of supplying the soft water is performed by an ion exchange resin.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings, but the present invention is not limited to the following embodiments.

FIG. 1 shows the structure of a cleaning apparatus according to an embodiment of the present invention. The object to be cleaned 14 cleaned in the cleaning agent tank 1 is rinsed in the first rinse tank 2.
The water supplied to the first rinse tank 2 passes through the water softener 12 and is supplied as soft water. Therefore, in the first rinse tank 2, the cleaning agent 11 does not react with the metal ions in the rinse water, and the generation of deposits can be prevented.

In FIG. 2, the rinse water supply 6 is supplied to the third rinse tank 5
It is a figure showing the cleaning device composition of the type which is carried out only and is made to feed forward by cascade 13. Water softener 12
Is connected to the rinse water supply 6 to the third rinse tank 5. Since the water that has been fed forward to the second rinse tank 4 and the first rinse tank 2 is also soft water, the same effect as in the case of FIG. 1 can be obtained.

FIG. 3 is a view showing the structure of a normal cleaning device. Since the water softening device 12 is not connected, the first rinse tank 2 is supplied with rinse water which is not softened. . Therefore, a precipitate is generated by reacting with the cleaning agent 11.

Example 1 A metal part was cleaned under the following conditions using an alkaline cleaning agent (A). Main components of detergent (A): potassium hydroxide (26%), water (40%), glycol solvent (10%), other (amines, silicates, anionic surfactants, etc.) Conditions of use: Used at a concentration of 100%. Wash at 60 ° C. Ultrasonic cleaning (40 KHz 1200 W).

Rinse: Structure as shown in FIG. Temperature 4
Rinse at 0 ° C. Ultrasonic cleaning (40KHz 1200
W).

In the line of water supplied to the first rinse tank, N
Attaching a denominator filled with a-type cation exchange resin,
Soft water having a hardness of 0 ppm was supplied. The rinse water supplies well water and is hard water having a hardness of 60 ppm in a state where it is not softened. Hard water was supplied to the second and third rinse tanks.

As a result, the rinse water was always transparent even if a cleaning agent was brought in, and no deposits or the like were generated on the wall or bottom of the tank. No deposit was found in the second rinse tank. In addition, cleaning failure of metal parts of the object to be cleaned did not occur.

(Comparative Example 1) Under the conditions shown in Example 1, the line for supplying to the first rinse tank was not equipped with a denimer filled with Na-type cation exchange resin, and groundwater which was not softened was supplied. The other conditions were as in Example 1.

As a result, the rinse water was always in a turbid state, and a deposit was deposited inside the pipe leading to the wastewater treatment.

Further, the object to be cleaned was reattached to the metal part, resulting in poor cleaning. Elemental analysis of the precipitate revealed that it was a substance composed of calcium and magnesium.

[0031]

EFFECTS OF THE INVENTION By using soft water in the rinsing step after the washing step, deposits are not generated in the plant infrastructure such as the washing device and drainage, and washing can be performed without applying a load.

[Brief description of drawings]

FIG. 1 is a diagram showing a typical cleaning device configuration for explaining the present invention.

FIG. 2 is a diagram showing a cleaning device configuration of a type in which rinse water is fed in advance.

FIG. 3 is a diagram showing a general configuration of a cleaning device.

[Explanation of symbols]

1 cleaning agent tank 2 First rinse tank 3 overflow 4 Second rinse tank 5 Third rinse tank 6 Rinse water supply 7 Rinse water drainage 11 cleaning agents 12 Water softener 13 Cascade 14 Items to be cleaned

Claims (5)

[Claims] 1. A cleaning method having a water rinsing step, wherein soft water is used in at least the first step of the rinsing step. 2. The cleaning method according to claim 1, wherein the soft water used has a hardness of 1.8 ppm or less. 3. A cleaning apparatus having a water rinsing step, having a function of supplying soft water to at least the first step of the rinsing step. 4. The cleaning apparatus according to claim 3, wherein the soft water supplied has a hardness of 1.8 ppm or less. 5. The cleaning apparatus according to claim 3 or 4, wherein the function of supplying soft water is performed by an ion exchange resin.