JP2001104968A - Dechlorinating agent for tap water - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dechlorinating agent for tap water capable of removing residual free chlorine contained in tap water such as bathtub water or the like simply and efficiently and capable of also sterilizing tap water such as bathtub water or the like simultaneously with dechlorination and a dechlorinating method of tap water such as bathtub water or the like using the dechlorinating agent. SOLUTION: A dechlorinating agent for tap water containing a substance dissolved in water to liberate hydrogen peroxide such as percarbonate or persulfate or aq. hydrogen peroxide as an effective component is used to dechlorinate water of a bathtub. When aq. hydrogen peroxide is used, aqueous hydrogen peroxide infiltrated in a polymer can be also used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dechlorinating agent for tap water which can remove available chlorine contained in tap water such as bath water, and a bath water using the dechlorinating agent for tap water. It relates to a method for dechlorination of tap water.

[0002]

2. Description of the Related Art Conventionally, a large number of water purifiers for tap water have been put on the market, and their dechlorination methods have often been adsorbed by activated carbon. In recent years, in order to reduce water flow resistance, products using granular activated carbon instead of powdered activated carbon, and products using carbon fiber have been increasing. Charcoal and bamboo charcoal and their processed products are also on the market as dechlorinating agents for bathtubs.

[0003] Further, as a chemical for dechlorination for bathtubs and the like, a water quality improving agent comprising L-ascorbic acid and ferric citrate (JP-A-8-66690),
Slowly soluble residual chlorine remover obtained by mixing and hardening ascorbic acid and a hardening agent such as quicklime (JP-A-11-1793)
No. 75), ascorbic acid, sodium thiosulfate,
Bath composition comprising crude drug etc. (JP-A-8-198743)
Publication), a chlorine-based bleaching solution comprising an aqueous solution containing a dye which is stable to L-ascorbic acid and a reducing agent and unstable to an oxidizing agent.
Detoxifying agent for disinfectant (Japanese Patent Laid-Open No. 11-57686), detoxifying chlorine-based bleaching / disinfectant containing aqueous reducing agent and coloring agent which is stable to reducing agent and unstable to oxidizing agent Bath water purifying agent containing a treating agent (JP-A-10-235335), a chlorine-based disinfectant and a reducing agent for dechlorination such as sulfite, ascorbic acid and thiosulfate (JP-A-9-235)
38686) and the like.

[0004] Recently, a product for dechlorination has been put on the market by installing a cartridge filled with a reducing agent for dechlorination such as sulfite, thiosulfate, L-ascorbic acid (vitamin C) in a shower head or the like. I have. A method of storing hot water in a bath tub through a shower head is partially used.

[0005]

However, a water purifier using activated carbon and carbon fiber is suitable for use in small quantities for drinking and cooking. As the number of large bathtubs exceeds, the need for substantially large equipment is required to fill the bathtub with water through the water purifier.

In the case of activated carbon or carbon fiber, the dechlorination action is physical adsorption, and the adsorption capacity depends on the water temperature. There is virtually no problem when only tap water is passed through, as in a water purifier, but in some cases, when hot water, such as a shower head, is passed through at very high temperature, the efficiency is reduced. Also, when using charcoal, bamboo charcoal, or activated charcoal products in a bathtub, chlorine is efficiently adsorbed when the water temperature is low, such as immediately after tap water has been applied. In such a case, chlorine adsorbed on activated carbon or the like may be released again.

Furthermore, when activated carbon, charcoal, carbon fiber, or the like is used, it is often difficult to visually determine whether the dechlorination capacity has reached its limit, and it is often the first time that it can be determined by smelling from bathtub water. In addition, there is a problem in that water passed through a water purifier such as activated carbon or a reducing agent can easily decompose various bacteria by dechlorination. When used as a shower, there is no storage part, and propagation of this germ is practically ignored, but when stored in a bathtub, it becomes unavoidable.

On the other hand, L-ascorbic acid, thiosulfate,
In the dechlorination method using a reducing agent for dechlorination such as sulfite, since the reducing agent also reacts with dissolved oxygen in water,
The drug is not only wastefully consumed besides dechlorination, but also consumes and reduces dissolved oxygen. As a result, there is a high possibility that anaerobic bacteria rapidly grow.

[0009] Tap water is chlorinated, and when such tap water is used as bath water, chlorine added for sterilization and disinfection remains as available chlorine only by boiling water.
Therefore, it produces an unpleasant chlorine odor, damages hair, and irritates the skin. Particularly for those who have atopic symptoms, the worries are serious. The object of the present invention is to
Not only can free and residual chlorine contained in tap water such as bathtub water be easily and efficiently removed, but also dewatering can be performed simultaneously with dechlorination and sterilization of tap water such as bathtub water. An object of the present invention is to provide a method for dechlorinating tap water such as bath water using a chlorinating agent or a dechlorinating agent for tap water.

[0010]

Means for Solving the Problems The present inventors have proposed an adsorbent-based dechlorinating agent, such as activated carbon, or an L-ascorbic acid, thiosulfate, sulfite, etc. In the process of earnestly studying a dechlorinating agent that can convert free residual chlorine in tap water such as bath water into harmless chlorine ions without using a reducing agent-based dechlorinating agent, the use of hydrogen peroxide causes The inventors have found that not only can residual chlorine be converted into harmless chlorine ions, but also that bath water can be sterilized, disinfected, and washed, and the present invention has been completed.

That is, the present invention provides a dechlorinating agent for tap water characterized by using a substance which releases hydrogen peroxide by dissolving in water or a hydrogen peroxide solution as an active ingredient (claim 1). 2. The dechlorinating agent for tap water according to claim 1, wherein the substance that dissolves and releases hydrogen peroxide is a peracid salt, and the peracid salt is percarbonate. And / or a persulfate, wherein the dechlorinating agent for tap water according to claim 2 (claim 3), or a hydrogen peroxide solution impregnated in a polymer is used as the hydrogen peroxide solution. The dechlorinating agent for tap water according to claim 1 or claim 4, wherein the dechlorinating agent for tap water is a dechlorinating agent for a bathtub. The present invention relates to a dechlorinating agent for tap water described in claim 5.

Further, the present invention provides a method for dechlorinating tap water, which comprises using a substance which dissolves in water to release hydrogen peroxide or a dechlorinating agent containing hydrogen peroxide as an active ingredient. 6) The method for dechlorinating tap water according to claim 6, wherein the tap water is bathtub water.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, the substance which dissolves in water to release hydrogen peroxide (hereinafter referred to as "hydrogen peroxide releasing substance") includes percarbonate, persulfate, pernitrate, perborate And metal peroxides such as sodium peroxide and zinc peroxide. Salts of peracids are chemically considered as hydrogen peroxides of the corresponding salts, for example percarbonate, also called peroxy dicarbonate or peroxo dicarbonate, is a hydrogen peroxide of carbonate. For example, sodium percarbonate, as shown in the following formula,
Releases hydrogen peroxide by dissolving in water. Na ₂ C ₂ O ₆ + H ₂ O → 2NaHCO ₃ + H ₂ O ₂

Hydrogen peroxide, including those derived from salts of peracids, is generally known to act as a strong oxidizing agent, but is also known to act as a reducing agent depending on conditions. I have. For example, when available chlorine is present, it reacts as in the following equation, releasing hydrochloric acid and oxygen. HClO + H ₂ O ₂ → HCl + H ₂ O + O ₂

After deactivating available chlorine, hydrogen peroxide acts as a hydrogen acceptor as shown in the following formula to exhibit an oxidizing effect. Due to this oxidizing action, sterilizing, disinfecting and washing effects are exhibited. In the case of hydrogen peroxide, unlike the case of L-ascorbic acid, thiosulfate, sulfite, etc., dissolved oxygen in water is not consumed. ^{_{H 2 O 2 + 2H + +}} 2e - → 2H 2 O

As described above, a peracid salt has a function of dissolving in water to release hydrogen peroxide to deactivate available chlorine, but when used as a bathtub dechlorinating agent, it may cause accidental ingestion. In this case, percarbonate and persulfate can be advantageously used in view of toxicity and availability. Specific examples of these percarbonates and persulfates include sodium percarbonate, sodium persulfate and potassium persulfate, and these can be used alone or in combination of two or more.

As the dechlorinating agent for tap water of the present invention, in addition to those containing a hydrogen peroxide-releasing substance such as the above-mentioned peracid salt as an active ingredient, a hydrogen peroxide solution in which hydrogen peroxide is dissolved in water is used. Those serving as active ingredients can also be mentioned. When using hydrogen peroxide or hydrogen peroxide derived from hydrogen peroxide-releasing substances as a bathtub dechlorinating agent, the required amount of hydrogen peroxide is determined by the available chlorine contained in the tap water that has entered the bathtub. A predetermined amount of hydrogen peroxide which corresponds to or slightly exceeds the deactivation of the fraction is preferred. If the amount of hydrogen peroxide is less than the predetermined amount, the dechlorination effect will be insufficient. Conversely, if it is more than the predetermined amount, not only will the dechlorination component be wasted, but if it is extremely large, the released hydrogen peroxide itself will be lost. Can irritate the skin and hurt the hair.

For example, most of the available chlorine concentration in tap water is actually 1 ppm or less.
It is often set at 2 ppm due to the design of the water purifier. Also available chlorine
Since 1 mol of hydrogen peroxide (molecular weight 34) is theoretically equivalent to 1 mol of (molecular weight 71), the water supply is controlled so that the concentration of hydrogen peroxide at the time of dissolving the drug is 1 to 100 ppm, preferably 2 to 10 ppm. It is preferable to adjust the concentration of hydrogen peroxide in the water. Hereinafter, the dechlorination method using the dechlorinating agent of the present invention will be described separately for a case where a hydrogen peroxide releasing substance is used and a case where a hydrogen peroxide solution is used.

When a hydrogen peroxide-releasing substance is used as an active ingredient of a dechlorinating agent, the dechlorinating agent is used in a state of being contained in a perforated container made of plastic, metal, fine ceramic, wood, bamboo or the like. be able to. In the case of this use method, for example, when used in a fixed state in a bathtub, the dechlorinating agent can be stably eluted for a long period of time, so that it is excellent in certainty, appearance, safety, etc. of the effect. I can say. In addition, since the replacement time can be determined by the decrease in the amount of the chemical in the perforated container, even if the dechlorination ability is lost as in the case of activated carbon or other adsorbents, it is not apparent because the appearance is not apparent, so that it is not used continuously. Examples of the form of the seed dechlorinating agent include a molded article containing a hydrogen peroxide-releasing substance, a molded article containing a hydrogen peroxide-releasing substance in a nonwoven fabric with controlled water permeability, and the like.

Known molding methods such as tableting, briquetting, extrusion molding, kneading, and injection molding can be used as a molding method for a molded article containing a hydrogen peroxide-releasing substance. In pressure molding such as tableting and briquetting, known components such as an excipient for adjusting the dissolution rate, a lubricant for improving tableting properties, and a binder can be blended. Such components include benzoic acid, adipic acid,
Various organic acids such as glycolic acid and salts thereof, calcium sulfate, magnesium sulfate, potassium sulfate, inorganic salts such as magnesium silicate, various starches, cellulose derivatives, polyoxyethylene derivatives, polyoxypropylene derivatives,
Specific examples thereof include polyvinyl alcohol, sodium alginate, gum arabic, various sugars, and derivatives of acetoacetic acid such as orthotoluidide acetoacetate. In addition, as a compounding component in extrusion molding, kneading, and injection molding, the melting point is 60 ° C. in consideration of use in a bathtub.
The above are desirable, and specific examples thereof include water-soluble polymers such as polyoxyethylene, surfactants such as polyethylene polypropylene block polymers, fatty acids and their derivatives, and salts thereof.

When the hydrogen peroxide-releasing substance is used in a state of being put into a nonwoven fabric, the hydrogen peroxide-releasing substance may be used alone.
It can also be used as granules or granules by spray granulation, fluid granulation and the like.

Next, when hydrogen peroxide solution is used as an active ingredient of the dechlorinating agent, the dechlorinating agent may be, for example, 30% hydrogen peroxide solution in a liquid form, or hydrogen peroxide in a polymer. And a film in which a hydrogen peroxide solution is stored in a film whose water permeability is controlled can be exemplified. The liquid form of the dechlorinating agent can be used, for example, as a bathing agent, by injecting tap water into the bathtub each time. Specifically, a method of injecting a predetermined amount from a bottle with a measuring cap or a pump type bottle, or enclosing the amount of each use in an aluminum pack, a vinyl pack, a small bottle, etc., and opening these at the time of use Injection method.

The polymer used as the dechlorinating agent in a form in which the above polymer is impregnated with hydrogen peroxide is not particularly limited, but is harmless even if it is eluted in a bath, and Those having an appropriate molecular weight, such as polyethylene glycol and polyvinyl alcohol, are preferable in that the end of the life of the agent can be visually judged. Further, as the film used for the dechlorinating agent in the form in which hydrogen peroxide solution is contained in the film whose water permeability is controlled, cellulose ester-based films, cellophane-based films, and water-impermeable films such as nylon Examples of such a film having a small hole can be given. In this case, the aqueous hydrogen peroxide solution is usually gelled and sealed in such a film with polyethylene glycol or the like.

A dechlorinating agent in which a polymer is impregnated with hydrogen peroxide, or a dechlorinating agent in which a hydrogen peroxide solution is contained in a film whose water permeability is controlled, are made of plastic, metal, fine ceramic, It can be used while housed in a perforated container made of wood, bamboo or the like. in this case,
For example, when used fixed in a bathtub, the dechlorinating agent can be stably eluted for a long period of time, so that it can be said that the dechlorinating agent is excellent in certainty of effect, appearance, safety and the like.
In addition, since the replacement time can be determined by the decrease in the amount of the chemical in the perforated container, even if the dechlorination ability is lost as in the case of activated carbon or other adsorbents, it is not apparent because the appearance is not apparent, so that it is not used continuously.

The dechlorinating agent of the present invention includes, in addition to the above-mentioned excipients, warm bath effect components (sodium bicarbonate, sodium sulfate, calcium sulfate, salt, etc.), humectants (eucalyptus extract, aloe extract, Ashitaba extract, rice bran extract, etc.), whitening components (kojic acid), blood circulation promoting components (pepper extract, touki extract, etc.), flavors, pigments, pH adjusters, corrosion inhibitors, antibacterial agents, etc. can be added, A reducing component that consumes hydrogen peroxide acting as a dechlorinating component,
For example, it is not preferable to add vitamin C, sulfites, sulfur compounds containing sulfur, and the like.

[0026]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the technical scope of the present invention is not limited to these examples. Further, in Examples and the like, what is indicated by% represents% by weight unless otherwise specified.

Example 1 35% sodium percarbonate, 45% calcium sulfate hemihydrate, hydroxypropylcellulose as binder, stearic acid as lubricant,
In addition, raw materials such as eucalyptus extract, touki extract, fragrance and pigment are mixed well, and the linear pressure is 9.8 × 10 ⁶ Pascal (Pa)
Was rolled and granulated by using a roller. Thereafter, the powder was crushed to an appropriate particle size, and a pressure of 80 t was applied to obtain 30 g of cylindrical tablets. This was stored in a plastic case with a suction cup, and used by attaching it to the inner wall of the bathtub near the bottom.

(Example 2) 10% of 30% hydrogen peroxide solution,
30% of polyethylene glycol having an average molecular weight of 1000, a fragrance and the like were dissolved in water, and filled into a one-push 3 mL pump-type bottle. In a bathtub with a bath, the water was boiled before boiling, and in a bathtub without a bath, a one-push drop was used when pouring hot water from a galant.

(Example 3) 10% of 30% hydrogen peroxide solution and 20% of polyvinyl alcohol having a polymerization degree of 2000 were dissolved in water and sealed in a perforated polyethylene-nylon-polyethylene three-layer film. This was placed in a plastic case with a suction cup and fixed to the bathtub wall near the bottom for use.

(Comparative Example 1) A commercially available shower having a shower head filled with a cartridge filled with L-ascorbic acid was used, and hot water was poured into a bathtub through the shower head.

(Control) Hot water was poured into the bathtub without using the chemicals used in Examples and Comparative Examples.

[Test 1] In Examples 1 to 3, Comparative Example 1 and the control group, about 200 L of hot water was poured into a Japanese-Western eclectic embedded bathtub (full water volume: 270 L) with a frontage size of 1200 mm, and the mixture was stirred gently. The effective chlorine amount was measured using a residual chlorine analyzer (DPD method) manufactured by Shibata Scientific Instruments Co., Ltd. Table 1 shows the results. As can be seen from Table 1, in Examples 1 to 3 and Comparative Example 1, residual available chlorine was not detected.

[0033]

[Table 1]

[Test 2] One adult took a bath after [Test 1] in Examples, Comparative Examples and Controls. After bathing, the lid was kept as it was and kept warm for 1 hour, and thereafter, whether or not Escherichia coli was present in the hot water in the bathtub was measured using coliform bacteria test paper manufactured by Shibata Scientific Instruments Co., Ltd. Table 2 shows the results. Table 2
It can be seen from the results of Examples 1 to 3 that the dechlorinating agent of the present invention has a bactericidal action. In Table 2, "-" means that no E. coli colonies were detected, "+" means that E. coli colonies were detected, and "++" means that the number of E. coli colonies was large. Is shown.

[0035]

[Table 2]

[0036]

By using the dechlorinating agent of the present invention, chlorine in tap water such as hot water in a bathtub can be removed for a long period of time without any trouble, and it is possible to prevent obstacles due to available chlorine. In addition, the dechlorinating agent of the present invention also has a bactericidal action, and does not use a reducing agent as a dechlorinating component, so that it does not consume dissolved oxygen in water and promotes the growth of anaerobic bacteria. Nothing.

Claims (7)

[Claims] 1. A dechlorinating agent for tap water, comprising a substance which releases hydrogen peroxide by dissolving in water or a hydrogen peroxide solution as an active ingredient. 2. The dechlorinating agent for tap water according to claim 1, wherein the substance that releases hydrogen peroxide by dissolving in water is a salt of peracid. 3. The dechlorinating agent for tap water according to claim 2, wherein the peracid salt is a percarbonate and / or persulfate. 4. The dechlorinating agent for tap water according to claim 1, wherein a hydrogen peroxide solution impregnated in a polymer is used as the hydrogen peroxide solution. 5. The dechlorinating agent for tap water according to claim 1, wherein the dechlorinating agent for tap water is a dechlorinating agent for bathtub. 6. A method for dechlorinating tap water, comprising using a substance that dissolves in water to release hydrogen peroxide or a dechlorinating agent containing hydrogen peroxide as an active ingredient. 7. The method for dechlorinating tap water according to claim 6, wherein the tap water is bathtub water.