JPH10140188A - Immersion material composition for cleaning plastic container and method of cleaning by using the composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to remove black stains firmly fixed to a plastic container after long-term service by immersing the plastic container in an immersion material containing an alkalizing agent and a surfactant, followed by automatic washing with a usual detergent. SOLUTION: This immersion material composition contains an alkalizing agent, such as NaOH or KOH, preferably in an amount of 10-80wt.% and a surfactant in an amount of 5-40wt.%. It is desirable to also incorporate an aminocarboxylic acid salt, a condensed phosphoric acid salt, etc., in an amount of 10-70wt.% into the composition. Water is added to the composition to give an immersion liquid. A plastic container is immersed in this liquid at ordinary temperature or preferably at 40-100 deg.C. The immersion time is about 10-1min when immersed at 50-70 deg.C. A suitable surfactant used comprises a nonionic surfactant having an HLB of 10 to 14, although various types of surfactants can be used. After the immersion, the plastic container is put in a washing machine and washed with a usual detergent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning immersion composition used for removing dark stains firmly adhered to the surface of a plastic container by long-term use, and a cleaning method using the same.

[0002]

2. Description of the Related Art Plastics are widely used in various fields because they are easy to process, light in weight and beautiful in appearance. In the distribution industry, various transportation methods and transportation means have been developed, and containers made of various plastic materials have been actively used. With such use, there is an increasing demand for cleaning plastic in order to carry out such maintenance. Soil adhered to the surface of plastic containers that have been used for long periods of time for shipping and storage, compared to those adhered to hydrophilic solid surfaces (specifically, glass and metal surfaces) It is bound by a strong adhesive force and is difficult to remove with a normal cleaning agent. Cleaning agents developed for plastic containers (JP-A-61-296097, 61-296098)
Is effective as a cleaning agent, but it is only for dirt and food and other attached dirt.
Darkening and dirt adhering to the surface of the plastic container over a long period of time can hardly be removed.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a cleaning immersion composition used for removing dark stains firmly adhered to the surface of a plastic container by long-term use, and a cleaning using the same. Is to provide a way.

[0004]

Means for Solving the Problems The present inventors have conducted research on the above-mentioned problems, and have been able to remove dark stains firmly adhered to the surface of a plastic container over a long period of use from a plastic container containing an alkali agent and a surfactant. After immersion in a cleaning immersion treatment liquid containing the cleaning container immersion composition for the stitch container, when the cleaning is performed using an automatic cleaning machine and a normal cleaning agent, darkening and dirt attached to the surface of the plastic container are removed. Finding that it can be almost removed,
The present invention has been completed. That is, according to the present invention, a cleaning immersion composition used before a normal cleaning treatment, wherein the immersion composition for cleaning a plastic container comprises an alkali agent and a surfactant. Is provided.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION An alkaline agent is used in the immersion treatment composition for cleaning of the present invention. As the alkaline agent,
Hydroxides and carbonates of alkali metals, and various silicates,
Alkanolamines and the like are used. Specific examples of the alkali metal include sodium and potassium. Examples of the alkali metal hydroxide include sodium hydroxide and potassium hydroxide. Examples of the alkali metal carbonate include sodium carbonate and potassium carbonate. Alkali metal silicates include sodium orthosilicate, potassium orthosilicate,
Examples thereof include sodium metasilicate and potassium metasilicate. Examples of the alkanolamines include monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, and triisopropanolamine. Among these, as the alkaline agent, sodium hydroxide, potassium hydroxide and the like are generally used. The concentration of the alkaline agent in the immersion composition for cleaning of the present invention is 5 to 80% by weight, preferably 10 to 80% by weight, based on the immersion composition for cleaning. The composition may be in any form as long as the composition can be adjusted to the above processing solution concentration. Examples of the form include solid, flake, powder, stick, liquid, and slurry. From the viewpoint of ease of handling, the liquid or slurry form of the immersion composition is preferably used. As the immersion treatment liquid for cleaning, the immersion composition for cleaning is 0.001 to 5% by weight, preferably 0.1 to 5% by weight.
Contains 1% by weight. If the concentration exceeds this range, the detergency will not be significantly improved, and if it is less than this range, the expected detergency cannot be obtained.

[0006] A surfactant is used in the cleaning immersion treatment agent of the present invention. As the surfactant, an anionic surfactant, a cationic surfactant, an amphoteric surfactant and a nonionic surfactant are used. Examples of anionic surfactants include alkyl benzene sulfonate, naphthalene sulfonate, petrolium sulfonate, naphthalene formalin condensate sulfonate, higher alcohol sulfate, higher alcohol ethoxy sulfonate, and alkylphenyl ethoxylate sulfate. Salts, alkyl phosphate salts, soaps, etc., and particularly, sodium salts and potassium salts are used as the salts. Examples of the cationic surfactant include an alkyl quaternary ammonium compound,
Alkyl pyridinium compounds, alkyl benzyl ammonium compounds, alkyl amine compounds, alkyl polyoxyethylene amine compounds, amine oxide compounds and the like are used. As the amphoteric surfactant, an alkylbetaine compound, a sulfobetaine compound, an alkylimidazolinium compound, an alkylaminopropionic acid compound, an alkyliminodipropionic acid compound and the like are used. As the nonionic surfactant, ethoxylated ethers, ethoxylated alkylphenols, ethoxylated octylphenols, ethoxylated sorbitan fatty acid esters, and propylene oxide adducts thereof can be used. Among them, the following general formula (1),
The surfactant represented by (2) gives good results. _{R 1 O (EO) n (} PO) mR 2 (1) R 1 O (EO) l (PO) kH (2) (R 1 is a linear or branched alkyl group having 6 to 24 carbon atoms, an alkenyl group Or an alkylphenyl group, R
₂ represents a linear or branched alkyl group or alkylphenyl group having 1 to 8 carbon atoms, EO represents ethylene oxide, and PO represents propylene oxide. n, m
Is 0 to 10, l is 5 to 12, preferably 6 to 8, k
Represents a number from 0 to 12, preferably from 2 to 5. EO,
When adding PO, random addition or block addition may be used. ) Among these surfactants, nonionic surfactants can easily penetrate hydrophobic dark stains, and can control foaming when used as a washing immersion treatment agent. It is generally used because it is superior to other surfactants in such points. As the HLB of the surfactant, a wide range of HLB can be selected and used, but 6 to 16, preferably 10 to 1
4 has a particularly high cleaning effect. If the ratio is less than this range, phase separation is not effective. On the other hand, when the amount exceeds this range, undesirable effects such as a decrease in detergency and an increase in foaming occur. When the cleaning immersion composition is made into a liquid or slurry, the surfactant is used in an amount of 0.5 to 60% by weight, preferably 5 to 60% by weight, based on the composition.
It is preferred that the content be in the range of -40% by weight. The surfactant is used in an amount of 0.01 to 5% by weight, preferably 0.1 to 5% by weight of the immersion treatment liquid for cleaning.
0.05 to 1% by weight. If the amount is less than this range, the expected effect cannot be obtained, and the amount is preferably 0.5 to 60% by weight, more preferably 5 to 40% by weight.

[0007] A chelating agent is used in the cleaning dip composition of the present invention. As the chelating agent, metal salts such as aminocarboxylic acid, oxycarboxylic acid, polymer and condensed phosphoric acid, particularly alkali metal salts such as sodium salt and potassium salt are used. Specific examples of the amino carboxylate include alkali metal ethylenediamine tetraacetate, alkali metal nitrilotriacetate, alkali metal hydroxyethylethylenediamine triacetate, alkali metal diethylenetriamine pentaacetate, alkali metal triethylene hexaacetate. And alkali metal human hydroxyimino diacetate, alkali metal hydroxyethylamino acetate, alkali metal glycine, alkali metal dihydroxyethyl glycine and the like. As oxycarboxylic acids,
Specific examples include gluconic acid, citric acid, glycolic acid, malic acid, tartaric acid, and lactic acid. As the polymer, specifically, carboxymethyl cellulose,
Polyacrylic acid, polymethacrylic acid, copolymers of acrylic acid and vinyl compounds, copolymers of maleic anhydride and vinyl compounds, copolymers of maleic anhydride and ethylene, and alkalis such as maleic acid polymers Metal salts and the like can be mentioned. Examples of the condensed phosphate include alkali metal pyrophosphate, alkali metal tripolyphosphate, alkali metal hexametaphosphate, and alkali metal polyphosphate. When it is in a liquid or slurry form, it is used in the range of 0 to 80% by weight, preferably 10 to 70% by weight, based on the immersion agent composition. The chelating agent is used in an amount of 0 to 2% by weight, and preferably 0.1 to 1% by weight, as an immersion treatment liquid for cleaning. If it is less than this range, the expected effect cannot be obtained, and even if it is used beyond this range, a special effect cannot be obtained as compared with this range.

In the cleaning immersion composition of the present invention, various additives may be used, if necessary, in addition to the above components. These components include organic or inorganic solidifying agents, solvents,
Stabilizers and other additives generally used for immersion agents and cleaning agents can be used.

The role played by these compounds is as follows. The alkaline agent added to the cleaning immersion composition,
It causes chemical reactions such as saponification and decomposition to dark stains. By this reaction, dark stains are removed from the plastic container. The surfactant added to the cleaning dip composition penetrates the dark stains, imparts affinity to the stains, and softens the black stains, and acts to easily disperse the dark stains in water. I have. In addition, the fact that dirt after cleaning is reattached,
It also acts as a hindrance. The chelating agent added to the immersion composition for cleaning prevents the formation of poorly soluble products due to the combination of soil such as dark spots and calcium ions present in the cleaning solution. Even if a chelating agent is not used, a sufficient cleaning effect can be obtained. In such a case, a sparingly soluble calcium compound is generated, which hinders the washing operation, resulting in a significant decrease in washing efficiency.

In the present invention, a washing immersion composition comprising the above-mentioned compound is added to water and mixed with stirring to obtain a washing immersion treatment liquid. A necessary amount of this immersion treatment liquid for cleaning is prepared in an immersion treatment tank. The temperature of the washing immersion treatment liquid in the immersion treatment tank may be room temperature, but in that case, there is a half-day particle immersion time. Usually, it is very effective to set the temperature to 40 to 100 ° C. As the immersion time, the temperature of the immersion treatment liquid for cleaning is 40
At ５０50 ° C., the immersion time of the plastic container to be treated requires at least about 1 hour to about 10 minutes. When the temperature of the immersion treatment liquid for washing is 50 to 70 ° C., at least about 10 to 1 minute is required.
When the temperature of the immersion treatment liquid for cleaning is 70 ° C., the treatment time is
About 1 minute is required. FIG. 1 shows the relationship between the immersion time and the treatment temperature in this immersion treatment. In this figure, it is necessary to perform the immersion processing of the plastic container under the conditions of the processing time and the processing temperature in the range indicated by A. After finishing the immersion processing, the plastic container is introduced into a cleaning machine and subjected to a cleaning processing using a normal cleaning agent. In addition to spray cleaning, there is a method of rubbing the surface of a plastic container with a brush or a washer, or a combination of these methods.
The required cleaning time is determined as appropriate in view of dirt and the like. After the washing operation, the surface of the plastic container is sufficiently washed off with water and dried.

[0011]

EXAMPLES The following tests were conducted to confirm the effects of the cleaning immersion composition of the present invention. Detergency test plastic container, using the cleaning immersion treatment liquid of the present invention,
After the immersion treatment under the conditions of the immersion time and the immersion temperature of the present invention, a normal cleaning treatment is performed, and then the surface is sufficiently rinsed with water, and then visually determined according to the following criteria. Judgment criteria All dirt (excluding damaged parts) can be removed. 5 points Dark stains can be considerably removed. 4 points Black stains can be partially removed. 3 points Only light dirt such as dust and food deposits can be removed. 2 points No effect. 1 point

[0012] Example 1 0.2 wt% sodium hydroxide as an alkaline agent, Sofutano as surfactants - Le EP7025 (nonionic surfactant C ₁₂ - ₁₄ branched alcohol (EO 7 mole, PO
2.5 mol addition), manufactured by Nippon Shokubai Co., Ltd.) 0.3% by weight
And a washing immersion treatment solution comprising water residue was prepared and fed into the immersion tank. A plastic container (made of polypropylene, used for about 3 years for product delivery in a convenience store, 60 x 45 x 15 cm) in this processing tank
At 70 ° C. for 15 minutes. After completion of the immersion treatment, the plastic container is placed in a container washer (IHI-457, manufactured by Ishikawajima-Harima Heavy Industries, Ltd.) for 7 hours.
Washing was performed at 0 ° C. under a condition of 0.2% by weight of a commercially available detergent for plastic containers (Breaker CL100, manufactured by Lion Hygene Co., Ltd.) for 1 minute. After washing with water. It was dried and evaluated according to the criteria of the aforementioned detergency test. Evaluation,
It was "3". The results are summarized in Table 1.

Example 2 0.3% by weight of sodium hydroxide as an alkaline agent, 0.1% by weight of a surfactant (sophthalanol EP7025), 0.3% by weight of a 4Na salt of EDTA as a chelating agent and water residue A cleaning immersion treatment liquid was prepared and fed into an immersion tank. In this processing tank, a plastic container (made of polypropylene, used for about 3 years in a convenience store and used for product delivery.
The immersion treatment was performed at 0 ° C. for 15 minutes. After completion of the immersion treatment, the plastic container was washed at 70 ° C. with a detergent (Breaker CL1) in the same container washer used in Example 1.
00) Washing was performed under the conditions of 0.2% by weight for 1 minute. After washing with water. It was dried and evaluated according to the criteria of the aforementioned detergency test. The evaluation was "5". The results are summarized in Table 1.

Comparative Example 1 A surfactant (sophthanol E) was used without using an alkali agent.
P7025) 0.1% by weight, EDT as a chelating agent
A washing immersion treatment solution comprising 0.3% by weight of 4Na salt of A and a water residue was prepared and fed into an immersion tank. In this processing tank, a plastic container (made of polypropylene, used at a convenience store for about 3 years for product delivery. 6
0 × 45 × 15 cm) at 70 ° C. for 15 minutes. After the immersion treatment, the plastic container
In the same container washer used in Example 1, 70
° C, 0.2% by weight of detergent (Breaker CL100), l
The washing was performed under the condition of minutes. After washing with water, it was dried and evaluated according to the criteria of the above-mentioned detergency test. The evaluation was "2". The results are summarized in Table 1.

Comparative Example 2 Without using a surfactant, 0.3% by weight of sodium hydroxide was used as an alkaline agent and EDTA was used as a chelating agent.
A washing immersion treatment solution comprising 0.3% by weight of Na salt and water residue was prepared and fed into an immersion tank. A plastic container (made of polypropylene, used in a convenience store for about 3 years for product delivery in this processing tank. 60 × 4
5 × 15 cm) at 70 ° C. for 15 minutes. After completion of the immersion treatment, the plastic container was washed in the same container washer used in Example 1 under the conditions of 70 ° C. and 0.2% by weight of a detergent (Breaker CL100) for 1 minute. After washing with water, it was dried and evaluated according to the criteria of the above-mentioned detergency test. The results are summarized in Table 1. The evaluation was "2".

[0016]

[Table 1] Note 1) The figures are% by weight in the immersion treatment liquid for cleaning.

Example 3 0.2% by weight of sodium hydroxide as an alkaline agent, 0.3% by weight of a surfactant (sophthalanol EP7025), 0.2% by weight of a 4Na salt of EDTA as a chelating agent and water residue A cleaning immersion treatment liquid was prepared and sent into the immersion tank. A plastic container (made of polypropylene, which has been used for about three years for product delivery in a convenience store, 60 × 45 × 15 cm) is put into
A immersion treatment was performed at 150C for 15 minutes. The same plastic container after the completion of the immersion treatment used in Example 1 was placed in the same container washer used in Example 1 at 70 ° C. and a detergent (Breaker CL100) 0.2% by weight for 1 minute. The washing was performed under the following conditions. After washing with water. It was dried and evaluated according to the criteria of the aforementioned detergency test. The evaluation was "5".
The results are as shown in Table-2.

Comparative Example 3 0.2% by weight of sodium hydroxide as an alkaline agent, 0.3% by weight of a surfactant (sophthalanol EP7025), 0.2% by weight of a 4Na salt of EDTA as a chelating agent and water A residual immersion treatment liquid for cleaning was prepared and fed into the immersion tank. In this processing tank, a plastic container (made of polypropylene, which has been used in a convenience store for about 3 years for product delivery.
The immersion treatment was performed only at 0 ° C. for 5 seconds. After completion of the immersion treatment, the plastic container was washed in the same container washer used in Example 1 under the condition of 70 ° C. using 0.2% by weight of a detergent (Breaker CL100). After washing with water, it was dried and evaluated according to the criteria of the above-mentioned detergency test. The evaluation was "2". The results are as shown in Table-2.

[0019]

[Table 2] Note 1) The number of composition is% by weight.

Examples 4 to 6, Comparative Example 4 The plastic container was subjected to the same immersion treatment and cleaning treatment under the same conditions as in Example 1 except that the immersion treatment temperature was changed. Table 3 summarizes the composition of the immersion treatment liquid for cleaning and the results of the detergency test. The immersion treatment temperature for cleaning was outside the scope of the present invention, and the other conditions were the same as in Example 1, and the experiment was conducted. Comparative Example 4
Are summarized in Table-3.

[0021]

[Table 3] Note 1) The number of composition is% by weight.

Examples 7 to 15 A plastic container was immersed and washed under the same conditions as in Example 1 by using various compounds in the immersion treatment composition for washing. Table 4 summarizes the composition of the cleaning immersion liquid and the results of the cleaning power test.

[0023]

[Table 4]

Example 16 Using a two-component mixed type immersion agent, each of the solutions A and B was 1%
The immersion treatment liquid contained therein was subjected to immersion treatment and cleaning treatment of the plastic container under the same conditions as in Example 1. As a result of the detergency test, the evaluation was "5". The composition of the two-pack mixed type immersion agent was as follows. Solution A (1 solution) Softanol EP7025 20% by weight Softanol 50 (manufactured by Nippon Shokubai Co., Ltd.) 10% by weight Propylene glycol 60% by weight Purified water Balance Solution B (2 solutions) Sodium hydroxide 20% by weight EDTA-4Na 20% by weight % Purified water balance

Example 17 A washing treatment was carried out under the same conditions as in Example 1 except that a washing immersion solution in which 1% of the following powder type immersion agent was dissolved was used as the washing immersion agent. As a result of the detergency test,
The evaluation was "5". Powder type immersion treatment agent Softanol EP5035 (manufactured by Nippon Shokubai Co., Ltd.) 10% by weight Sodium hydroxide 40% by weight EDTA-4Na 20% by weight Sodium sulfate Balance

[0026]

According to the present invention, an immersion treatment composition capable of removing dark stains firmly adhered to the surface of a plastic container by long-term use, and a plastic container surface by using the composition, By long-term use, dark stains firmly adhered can be removed.

[Brief description of the drawings]

FIG. 1 is a diagram showing the relationship between immersion time and immersion temperature in the cleaning method of the present invention.

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[Procedure amendment]

[Submission date] September 5, 1997

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0002

[Correction method] Change

[Correction contents]

[0002]

2. Description of the Related Art Plastics are widely used in various fields because they are easy to process, light in weight and beautiful in appearance. In the distribution industry, various transportation methods and transportation means have been developed, and containers made of various plastic materials have been actively used. With such use, there is an increasing demand for cleaning plastic in order to carry out such maintenance. Soil adhered to the surface of plastic containers that have been used for long periods of time for shipping and storage, compared to those adhered to hydrophilic solid surfaces (specifically, glass and metal surfaces) It is bound by a strong adhesive force and is difficult to remove with a normal cleaning agent. The cleaning agent developed for plastic containers (Japanese Patent Application Laid-Open Nos. 61-296097 and 61-296098) is surely effective as a cleaning agent, but it is only for soil and dirt adhered to food and the like. In addition, darkening and dirt adhered to the surface of the plastic container over a long period of use can hardly be removed.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0003

[Correction method] Change

[Correction contents]

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a cleaning immersion composition used for removing darkening and dirt firmly adhered to the surface of a plastic container by long-term use, and to use the immersion composition for cleaning. The purpose is to provide a cleaning method.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0005

[Correction method] Change

[Correction contents]

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION An alkaline agent is used in the immersion treatment composition for cleaning of the present invention. As the alkaline agent,
Hydroxides and carbonates of alkali metals, and various silicates,
Alkanolamines and the like are used. Specific examples of the alkali metal include sodium and potassium. Examples of the alkali metal hydroxide include sodium hydroxide and potassium hydroxide. Examples of the alkali metal carbonate include sodium carbonate and potassium carbonate. Alkali metal silicates include sodium orthosilicate, potassium orthosilicate,
Examples thereof include sodium metasilicate and potassium metasilicate. Examples of the alkanolamines include monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, and triisopropanolamine. Among these, as the alkaline agent, sodium hydroxide, potassium hydroxide and the like are generally used. The concentration of the alkaline agent in the immersion composition for cleaning of the present invention is 5 to 80% by weight, preferably 10 to 80% by weight, based on the immersion composition for cleaning. The composition may be in any form as long as the composition can be adjusted to the above concentration. The form is solid, flake, powder, stick,
There are a liquid form and a slurry form. From the viewpoint of ease of handling, the liquid or slurry form of the immersion composition is preferably used. As an immersion treatment liquid for cleaning, an alkali agent is used at 0.0
It is contained in an amount of 0.1 to 5% by weight, preferably 0.1 to 1% by weight. If the concentration exceeds this range, the detergency will not be significantly improved, and if it is less than this range, the expected detergency cannot be obtained.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction contents]

[0007] A chelating agent is used in the cleaning dip composition of the present invention. As the chelating agent, metal salts such as aminocarboxylic acid, oxycarboxylic acid, polymer and condensed phosphoric acid, particularly alkali metal salts such as sodium salt and potassium salt are used. Specific examples of the aminocarboxylate include alkali metal ethylenediamine tetraacetate, alkali metal nitrilotriacetate, alkali metal hydroxyethylethylenediamine triacetate, alkali metal diethylenetriaminepentaacetate, and alkali metal triethylene.
Tetraamine 6 acetates, alkali metal arsenate de Rokishiimino 2 acetate, alkali metal hydroxyethylamino acetate salts, and alkali metal glycine, alkali metal dihydroxy ethyl glycine and the like. Specific examples of the oxycarboxylic acid include gluconic acid, citric acid, glycolic acid, malic acid, tartaric acid, and lactic acid. Specific examples of the polymer include carboxymethyl cellulose, polyacrylic acid, polymethacrylic acid, a copolymer of acrylic acid and a vinyl compound, a copolymer of maleic anhydride and a vinyl compound, and maleic anhydride and ethylene. And alkali metal salts such as a maleic acid polymer. Examples of the condensed phosphate include alkali metal pyrophosphate, alkali metal tripolyphosphate, alkali metal hexametaphosphate, and alkali metal polyphosphate. In the case of a liquid or slurry, 0 to 80 with respect to the immersion treatment composition.
%, Preferably in the range of 10 to 70% by weight. The chelating agent is used in an amount of 0 to 2% by weight, and preferably 0.1 to 1% by weight, as an immersion treatment liquid for cleaning. If it is less than this range, the expected effect cannot be obtained, and even if it is used beyond this range, a special effect cannot be obtained as compared with this range.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shoichi Miyano 1-3-7 Honjo, Sumida-ku, Tokyo Inside Rion Co., Ltd. (72) Takao Matsushita 1-3-7, Honjo, Sumida-ku, Tokyo No. Lion Corporation

Claims (4)

[Claims] 1. An immersion composition for cleaning plastic containers, comprising an alkali agent and a surfactant. 2. The immersion composition for cleaning plastic containers according to claim 1, further comprising a chelating agent in addition to the alkali agent and the surfactant. 3. The immersion composition for cleaning according to claim 1, wherein the alkali agent is an alkali metal hydroxide and the surfactant is a low foaming surfactant having an HLB of 10 to 14. 4. An object to be cleaned is immersed in an immersion treatment liquid for cleaning containing the immersion composition for cleaning according to claim 1, 2 or 3 at room temperature or under heating, and then washed with an automatic washing machine. Cleaning method.