JPH07118103A - Method for treating stainless steel processed part in electric washing machine with antimicrobial and antifungal agent composition - Google Patents

Abstract

PURPOSE:To provide a method for always keeping the outside and inside of the tank in an electric washing machine and the wash clean by coating the outer wall of the washing tank, the inside wall of the water receiver with a coating material containing an antimicrobial and antifungal agent to form an antimicrobial coating layers to control the growth of microorganisms for a long period of time. CONSTITUTION:The outer wall of the washing and dewatering tank 1 and the inner wall of the water receiver 2 both of which are made of processed stainless steel are coated with a coating material containing a antimicrobial and antifungal agent so that the antimicrobial and antifungal coating layers control the growth of bacteria, molds, yeasts and the like and prevents them from forming depositions whereby the wash is prevented from being contaminated with the microorganisms. The antimicrobial and antifungal agent is singly 2-pyridine-thiol 1-oxide zinc salt or a combination thereof with zinc oxide at a ratio of 1/1-1/20 and used in an amount of 0.01 to 5.0%, preferably 0.05 to 3.0% in case of a liquid coating or 0.05 to 2.0% in case of powdery one. As a coating to be used, are cited an epoxy resin, acrylic resin, polyester resin, polyurethane resin, fluorine resin and the like.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an outer wall of a rotary washing tub / dehydration tub (hereinafter simply referred to as a washing tub) and a water receiver of a fully automatic electric washing machine using stainless steel in a portion in contact with washing and cleaning wastewater. The present invention relates to a method of forming an antimicrobial coating film layer with a coating material in which an antibacterial and antifungal agent is dissolved or dispersed on the inner wall of a tank. More specifically, the site, which is a completely inaccessible place, is contaminated with bacteria, mold, yeast, etc. during long-term use, and slime deposits are formed. The deposit peels and disperses in the wash water. This results in microbial contamination of the wash water and laundry.

Stainless steel has a relatively good drainage and is less likely to be contaminated by cleaning liquids. But,
This makes it difficult to prevent slime. Detergents such as metal soaps, anionic surfactants and nonionic surfactants used in washing liquids, or oily substances and stains such as proteins from laundry are gradually attached to the stainless steel surface, and bacteria and mold , Microorganisms such as yeast propagate and gradually form slime deposits. The present invention is
Growth of these microorganisms, bactericidal, by the coating film of a paint containing a fungicide, the result of suppressing the growth of microorganisms,
The present invention relates to providing a fully automatic electric washing machine in which an outer wall of a washing tub, an inner wall of a water receiving tub, and the like are less likely to be contaminated by microorganisms, and which is always kept clean to obtain hygienic laundry.

[0003]

2. Description of the Related Art As a result of the demands for improvement of living environment and automation of washing in general households, self-powered washing machines have been widely used in the market instead of the conventional two-layer type. Most of the fully-automatic washing machines at the time of sale used thermoplastics that were easy to mass-produce.

After that, it was pointed out that the plastics used in the washing tub and the water receiving tub part become unsanitary due to the generation of microorganisms. As a solution to this problem, it was recommended to disperse and blend antibacterial and antifungal agents into thermoplastic molded parts that come into contact with washing water in parts used in washing machines. Was given.

Instead of dispersing antibacterial and antifungal agents in this thermoplastic synthetic resin, a fully automatic electric washing machine using stainless steel, which has a smooth surface and is considered to have a relatively small amount of microbial contamination, has come into consideration. This problem,
Recently, each manufacturer has come to consider it sequentially. Although it is superior in strength to stainless steel thermoplastic synthetic resin, commercial products are not particularly subjected to antibacterial and antifungal treatments.

However, even in a washing machine using stainless steel, there is a concern that damage due to microorganisms may occur. As microorganisms commonly found in washing machines, it has been observed that molds such as Penicillium spp., Aspergillus spp., Alternaria spp., Cubularia spp., Mucor spp., As well as yeasts and a large number of bacteria breed.

A method for dispersing an antibacterial and antifungal composition in an electric washing machine or molding a coating layer is disclosed in JP-A-2-2431.
94. According to the published patent publication, a method of dispersing an antibacterial and antifungal composition in a thermoplastic resin or forming an antimicrobial coating film layer on these resins is disclosed. In addition, an antibacterial and antifungal composition used for it is also introduced. However, when compounded with a resin, heat resistance is the most important condition because it is kneaded at the melting temperature of the resin. Generally, there are very few antibacterial and antifungal agents that can withstand the melting temperature of the resin, and it is usually accompanied by decomposition and discoloration.

[0008]

SUMMARY OF THE INVENTION A fully automatic electric washing machine is
Unlike the two-tub type in which a washing tub and a dehydrating tub are separately provided, the washing tub also serves as a dehydrating tub, and a water receiving tub is provided outside thereof. In this washing tub, the laundry is agitated with the detergent by the water flow generated by the rotating blades, and the laundry is washed and dehydrated each time it is washed or washed with water. Conventionally, plastic has been mainly used for parts used in the cleaning tank and the water receiving tank.

This portion is constantly in contact with the wash water,
Since the humidity is 100% or more even after dehydration, the plastic always has moisture and does not dry. In addition, since plastic is relatively difficult to strengthen, it is reinforced in various ways, so the surface is not smooth and is reinforced by considerable unevenness, so it is used for washing metal soaps and general surfactants or laundry products. Dirt cannot enter and cannot be easily removed. Further, plastic is a material that is relatively soft and easily scratched because a plasticizer is used.
As a result, a wound is formed during use, and the growth of microorganisms is also observed in this wound.

As a method for suppressing such contamination by microorganisms, the object has been achieved by incorporating an antibacterial and antifungal agent that can withstand the molding temperature of thermoplastics. After that, it was considered to further improve the material of the washing machine, and the washing machine using stainless steel which is well drained, hard to be scratched, has excellent strength, and can be molded by pressing is also seen in the market. It became so.

The used portion of stainless steel is mainly used for directly washing laundry such as a washing tub and a water receiving tub, and is used in a portion where washing water comes into contact.
Looking at the parts where mold, bacteria, yeast, etc. propagate due to detergent or dirt that is separated from laundry by washing in a fully automatic washing machine, the inside of the washing tub can be easily washed, and it can be washed with laundry. Very little microbial growth on the wall due to friction inside. Further, even if the occurrence is seen, it is relatively possible to remove it.

However, the outer wall of the washing tub and the inner wall of the water receiving tub are completely out of reach. Every time the washing machine is used, fats and proteins from the laundry stains, or meals such as detergents such as metal soaps and surfactants, etc., adhere to such places every time the washing machine is used. Microbes such as mold, bacteria, and yeast accumulate as slime and accumulate. When they are deposited to some extent, they are peeled off by mechanical shock during washing, dispersed in wash water and wash water, and contaminate the laundry. This fact was confirmed by the increase in the number of microorganisms in the washing water.

[0013]

According to the present invention, an antimicrobial coating layer is formed on the outer wall of a washing tub which cannot be reached and the inner wall of a water receiving tub with a coating containing an antibacterial and antifungal agent for a long period of time. It is a method that can suppress the generation of microorganisms and keep the inside and outside of the washing machine tub and the laundry always clean.

As described above, the present invention relates to a stainless steel used for a washing tub and a water receiving tub which a washing liquid contacts during washing in a fully automatic electric washing machine for removing dirt of laundry contained in the washing tub as described above. Molds, bacteria, etc. on places where cleaning is not possible, such as the outer wall of the washing tub and the inner wall of the water receiving tub.
The coating film of a paint containing an antibacterial and antifungal agent that suppresses the growth of microorganisms such as yeast is prepared to suppress the growth of these microorganisms.

A large number of compounds have been studied and taken up as agents to be used for suppressing the growth of microorganisms. Done. The baking process is carried out at 150 to 300 ° C. for about 1 minute, but there are few that satisfy this condition and a special compound is required.

The antibacterial and antifungal agents usable for the inner wall of the washing tub and the outer wall of the water receiving tub of the electric washing machine of the present invention are 2-pyridinethiol-1-oxide zinc salt alone and zinc oxide in the range of 1: 1 to 1:20. The present invention has been completed by discovering that the antibacterial and antifungal properties are improved and that the heat resistance is particularly improved by blending in the proportion of.

These antibacterial and antifungal agents can be used as they are, but after they are treated with inorganic powder such as calcium carbonate, ceramics, zeolite, zinc oxide, kaolin clay, talc, bentonite and diatomaceous earth as a carrier, It can be used by being blended with a paint.

The paint used for forming a coating film containing a drug used for suppressing the growth of microorganisms is
Epoxy resin paints, acrylic resin paints, polyester resin paints, polyurethane resin paints, fluororesin paints, etc. that have high hardness that is hard to be scratched by heating and weather resistance, heat resistance, oil resistance, chemical resistance Since there are paints that are excellent, have good flexibility, or particularly coating films that have good electrical characteristics, it is necessary to select a paint suitable for each.

As the paint, it is necessary to evaporate the solvent after brush coating or spray coating, and then heat treatment to improve the strength of the coating film. In addition to liquid coating, powder coating may be used. it can. The powder coating includes epoxy type, thermosetting polyester urethane type, thermosetting acrylic type, thermosetting polyester type and the like.

The method of coating powder coating is to preheat the article to be coated,
There are a fluidized dipping method of dipping in a paint powder tank, an electrostatic powder spraying method, an electrostatic fluidized dipping method, a thermal spraying method and the like. In the method of blending the antibacterial / antifungal agent composition with the powder coating, the antibacterial / antifungal agent composition is also made into a fine powder and then used, or it is melted together with the coating material and then pulverized again.

Any paint is used which is hardened by heating. The baking temperature for forming a coating film is 150 to 2
A good coating film can be obtained by baking at 50 ° C. or higher at about 300 ° C. for about 1 minute. The coating is carried out by coating once, baking once, or coating twice and baking twice. The amount of paint applied is about 50 g / m ² or thickness 20
± 5 μm is suitable.

The content of the antibacterial and antifungal agent in each resin coating is 0.01 to 5.0% in the liquid coating, preferably 0.1.
Is 3.0%, and powder coating is 0.05% to 2.0%.
To be added to water-based paints, it is dispersed in water as fine particles with a surfactant, or dissolved in a solvent and then added with the surfactant added, or this liquid is added into water and emulsified and dispersed. Used as a self-emulsifying formulation. In addition, it can be used as it is in oil-based paints. Further, it is possible to use a combination of a potentiator for antibacterial and antifungal agents, a UV inhibitor, an antioxidant and other antibacterial and antifungal agents. A colorant can also be added.

[0023]

The present invention is a stainless steel part constituting a fully automatic electric washing machine, in which contaminated water such as dirty washing liquid or a portion in contact with the washing liquid, particularly the outer wall of the washing / dehydrating tub and the inner wall of the water receiving tub is attached. It is used by blending it with acrylic resin paints that have antibacterial and antifungal agents added to the parts that are left as they are, normal temperature curing type epoxy resins, bake curing type epoxy resin paints and other paints. This is a method in which a coating material containing this agent is applied to a stainless steel portion and then baked to form a coating layer to prevent the growth of microorganisms such as bacteria, mold and yeast.

The substances that dissolve in the washing water during washing include not only fats, proteins and other stains from the human body attached to clothes, but also synthetic detergents and metallic soaps used for washing.
Various other surfactants are included. The amount of dirt contained in the wash water and the rinse water at the time of washing adheres to the washing machine as the washing is repeated, and the amount thereof gradually increases. The inner wall of the rotary washing tub, which is in contact with the contaminated water of the washing machine, is made of stainless steel, is smooth, and is washed by friction with the laundry. In addition, it is easy to wash the dirty part of every corner of the inner wall of the washing tub by hand.
Microorganisms such as bacteria and yeast do not adhere to the surface very often.

However, in places such as the outer wall of the washing tub and the inner wall of the water receiving tub which are completely out of reach, mold, bacteria,
Microorganisms such as yeast propagate and become slime, gradually forming deposits. These deposits cannot be removed by ordinary households, and the laundry is contaminated with microorganisms every time it is washed.

When the coating layer forming treatment with the antibacterial / antifungal agent-containing paint of the present invention is applied, the outer wall of the washing tub and the inner wall of the water receiving tub in the portion where the washing liquid of the fully automatic washing machine comes into contact are completely out of reach. However, the contamination of microorganisms such as mold, bacteria, yeasts, etc. is eliminated, and the laundry can be always kept clean. Hereinafter, detailed description will be given with reference to examples. However, the present invention is not limited to these examples.

[0027]

【Example】

(Embodiment 1) A sectional view of a fully automatic electric washing machine of the present invention is as shown in FIG.
Is a rotary washing tub / dehydrating tub, and 2 is a water receiving tub, each made of stainless steel. According to the present invention, the outer wall of the rotary washing tub / dehydrating tub and the inner wall of the water receiving tub are coated with a paint containing an antibacterial / antifungal agent. The shaded area is a portion where cleaning cannot be performed at all, and even if slime due to mold, bacteria, yeast, etc. occurs, it cannot be removed and the slime gradually accumulates.

The present invention is a method for suppressing the generation of microorganisms, and the shaded portion is the place where the growth of microorganisms is the most violent in a place where cleaning cannot be performed at all. here,
The part surrounded by the outer wall of the rotating washing and dehydrating tub and the inner wall of the water receiving tub prevents microbial growth in this part. In this figure, 1 and 2 are as described above. Reference numeral 3 is a rotary blade that causes a water flow, and 4 is a drain pipe, which is made of rubber or resin and in which an antibacterial and antifungal agent is kneaded is used to prevent generation of microorganisms on the inner surface. Reference numeral 5 denotes a motor for rotating the rotary washing tub / dehydration tub, and 6 denotes a bearing portion of the rotary blade.

The antibacterial and antifungal agent used as an antibacterial and antifungal paint on stainless steel is 2-pyridinethiol-1.
-Oxide zinc salt alone As a result of conducting two types of comparative tests, one in which calcium carbonate which does not exhibit antibacterial and antifungal properties is used and the other in which zinc oxide is blended, the results are shown in Tables 1 to 4. Since an excellent effect was obtained as compared with the calcium carbonate combined drug, all the subsequent tests were performed with a drug containing zinc oxide. The coating method and the antibacterial and antifungal test were conducted as follows. Drugs used No. 1,2-pyridinethiol-1
-Oxide zinc salt 20%, zinc oxide 80% Blend No. No. 2,2-pyridinethiol-1-oxide zinc salt 20%, calcium carbonate 80% Compounding agent Additives No. 1, No. 2 1.0, 3.0, 5.0, respectively
10.0% and additive-free polyester coating (Dainippon Paint Co., Ltd.)
Product) Paint preparation method The chemicals used were crushed to a particle size of 20 microns or less, added to the paint, stirred well, uniformly dispersed, applied to stainless steel, and baked. Used stainless steel plate SUS304 Thickness:
0.6 mm

Coating conditions: Coating solid content 45% Coating composition 2 coatings, 2 bakings Coating thickness 1st coating 5μm 2nd coating 18μm Baking temperature 280 ° C Baking time 60 seconds

An antibacterial and antifungal test of stainless steel coated with the above-mentioned trial paint containing antibacterial and antifungal agents was conducted under the following conditions. The test method is as follows. Antibacterial test method: According to JIS L 1902 halo method. Species used in the test Staphylococcus aureus ATC
C 6538P Escherichia coli 0-16 Antifungal test method: According to JIS Z 2911. Mold used in the test Penicillium citrinum FERM
S-5 Aspergillus niger FERM S-
No. 1 according to the above test The results of the antibacterial test with one drug are shown in Table 1, and the results of the antifungal test are shown in Table 3. In addition, No. The results of the antibacterial test with the two drugs are shown in Table 2, and the results of the antifungal test are shown in Table 4.

[0033]

[Table 1]

[0034]

[Table 2]

[0035]

[Table 3]

[0036]

[Table 4] The judgment value of the above-mentioned mold prevention test is based on the display method of the mold prevention test judgment shown in Table 5.

Table 5 shows the method of displaying the antifungal test judgment.

[Table 5] (Note) In the display method of the mold resistance test (JIS Z-2911), if there is a further inhibition zone in display 3, the size of the inhibition zone is displayed in mm on the right side.

Display Method of Antibacterial Test Judgment The antibacterial test judgment method by the halo method is effective when the halo is present and invalid when the halo is not present.

A coating layer of an antibacterial and antifungal agent-containing paint was formed on a stainless steel plate, and a test was conducted on the antibacterial and antifungal property of the sample after the severe conditions were applied to the coated surface. Test method If the time required for one wash is 45 minutes, and if it is washed once every day, it will take about 685 hours for 365 days (one year), so the painted stainless steel plate will be placed in running water for 57 hours (about 1 month). Equivalent), 171 hours (equivalent to about 3 months), 3
It was immersed in running water for 42 hours (corresponding to about 6 months), 685 hours (corresponding to about 1 year), 2055 hours (corresponding to about 3 years) and 3425 hours (corresponding to about 5 years). As for the water amount, the required water amount for one washing was 135 liters, and the washing time was 45 minutes. The results of the antibacterial test after the severe conditions are shown in Tables 6 and 7. Also,
The test results for antifungal properties are shown in Tables 8 and 9.

[0040]

[Table 6]

[0041]

[Table 7]

[0042]

[Table 8]

[0043]

[Table 9]

[0044]

EFFECTS OF THE INVENTION It has been attempted to use stainless steel as a washing tub / dehydrating tub and a water receiving tub of a full-automatic electric washing machine instead of a conventional thermoplastic resin. Stainless steel has a smooth surface, is well drained, and is considered to have little microbial contamination. However, detergents such as metal soaps and nonionic surfactants used for washing and stains of laundry adhere to the outer wall of the washing tub and the inner wall of the water receiving tub. Since this deposit adhering place is a completely inaccessible place, the deposit cannot be easily removed. The present invention suppresses the growth of these microorganisms by a coating layer of a paint containing a sterilizing and antifungal agent on the surface of this stainless steel, and minimizes the microbial contamination of water used for washing. This is a way to keep it always clean.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of a fully automatic washing machine according to the present invention.

[Explanation of symbols]

 1 Washing and dewatering tank (stainless steel) 2 Water receiving tank (stainless steel) 3 Stirring blade 4 Drain pipe 5 Motor 6 Bearing part of stirring blade

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[Procedure amendment]

[Submission date] December 3, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Brief description of the drawing

[Correction method] Change

[Correction content]

[Brief description of drawings]

FIG. 1 is a structure of an electric washing machine device used in an embodiment of the present invention.
FIG. 3 is a vertical cross-sectional explanatory view of a main part of FIG .

[Explanation of symbols] 1 Washing and dewatering tank ( composed of stainless steel) 2 Water receiving tank ( composed of stainless steel) 3 Stirring blade 4 Drain pipe 5 Motor 6 Bearing portion of stirring blade

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display area A01N 59:16)

Claims (4)

[Claims] 1. A method for removing stains on a textile product by washing a laundry containing water in a washing tub by an electric motor with a washing liquid containing metal soap, synthetic detergent or other surfactant by agitating the rotor blades. A washing machine in which the rotating washing tub / dehydrating tub and the water receiving tub that come into contact with the washing liquid of the automatic electric washing machine are made of stainless steel, and the outer wall of the unwashable washing tub and the inner wall of the water receiving tub are antibacterial and antifungal agents It is used to form a coating layer with antibacterial and antifungal properties by using a paint that mixes with the composition to prevent the growth of bacteria, mold, yeast, etc. and prevent the deposition of deposits by microorganisms. A method for processing an antibacterial / antifungal agent composition on a stainless steel processed part of an electric washing machine, which is characterized. 2. A 2-pyridinethiol-containing antibacterial / antifungal agent composition for a paint to be applied to a stainless steel processed part.
1-oxide zinc salt or 2-pyridinethiol-1
-1: 1 to 1:20 of zinc oxide to oxide zinc salt
The method for processing an antibacterial / antifungal agent composition on a stainless steel processed part of an electric washing machine according to claim 1, wherein the agent is compounded in a ratio of 1. 3. An antibacterial / antifungal agent is mixed with a coating material containing a compound containing a porous inorganic fine powder such as calcium carbonate, zinc oxide, ceramics, zeolite, kaolin clay, talc, bentonite, diatomaceous earth, etc., and applied. Item 1
2. A method for processing an antibacterial and antifungal composition on a stainless steel processed part of an electric washing machine according to 2. 4. A fully automatic washing machine which uses stainless steel as a rotary washing tub / dehydrating tub and a water receiving tub of a fully automatic electric washing machine, is coated on the outer wall of the rotary washing tub / dehydrating tub and the inner wall of the water receiving tub. Antibacterial and antifungal paints include epoxy resin paint, acrylic resin paint, polyester resin paint,
4. An antibacterial and antifungal composition is used in an amount of 0.01 to 3.0% by blending with an aqueous paint or an oil paint such as a polyurethane resin paint and a fluororesin paint, or a powder paint. A method for processing an antibacterial and antifungal composition on a stainless steel processed part of the electric washing machine as described above.