JPWO2011114976A1 - Antibacterial agent for water treatment, method for producing antibacterial agent for water treatment, and water treatment method - Google Patents

Abstract

An object of the present invention is to allow antibacterial treatment by eluting silver ions at a constant concentration that is not excessive or insufficient with respect to clean water such as drinking water and circulating water, and to maintain silver elution ability for a long period of time. It is providing the antibacterial processing agent which can be used, and the water treatment method using the same. The resin composition comprises a resin having a standard moisture content of 1 to 10% by weight and 1 to 30% by weight of silver-substituted zirconium phosphate represented by the formula [1] as an antibacterial agent. An antibacterial agent for water treatment. AgaMbZrcHfd (PO4) 3 · nH2O [1] In the formula [1], M is at least one ion selected from the group consisting of alkali metal ions, alkaline earth metal ions, ammonium ions, hydrogen ions and oxonium ions. A, b and c are each independently a positive number, d is 0 or a positive number, and n is 0 or a positive number of 2 or less.

Description

  The present invention relates to an antibacterial agent for water treatment and a method for producing the same, comprising a resin composition containing a resin having a specific standard moisture content and a specific silver-based inorganic antibacterial agent. The present invention also relates to a water treatment method for performing antibacterial treatment of water by bringing the antibacterial treatment agent for water treatment of the present invention into contact with various types of water.

  Various antibacterial agents for water treatment have been proposed depending on the application, target water, water flow rate, and the like. For example, a water treatment in which silver particles are supported in a treatment solution having a pH that does not destroy the crystal structure of zeolite in zeolite particles or zeolite-based processed products of any size that can be solid-liquid separated for water treatment. A silver-supporting antibacterial agent has been proposed (see, for example, Patent Document 1). Also, by adding a glass water treatment agent consisting of soluble glass containing monovalent silver ions in the composition to cooling towers, water tanks, pools, solar systems, irrigation water, etc., elutriation bacteria such as slime and algae and elutriation Proposals have been made to prevent the occurrence of organisms. (For example, see Patent Document 2)

  Also proposed is an antibacterial water treatment medium comprising a fiber mass in which a plurality of short fibers in which an antibacterial agent obtained by supporting a metal or metal ion having antibacterial performance on a phosphate is contained in the fiber is intertwined. ing. (For example, see Patent Document 3)

  In addition, a water treatment filter for removing contaminants from water, characterized by solidifying a zeolite carrying an antibacterial metal ion together with activated carbon with a binder comprising a high molecular weight porous polymer. (For example, refer to Patent Document 4) and a water purifier having excellent antibacterial properties (for example, refer to Patent Document 5) comprising a zirconium phosphate compound carrying and binding silver and activated carbon.

  In addition, a resin composition is formed by melt-mixing a mixture containing a silver-based inorganic antibacterial agent, an alkali metal and / or alkaline earth metal halogen salt, and a polyolefin resin, and subjecting the mixture to water treatment. An antibacterial resin molded product that suppresses the growth of varicella has been proposed, characterized by having a microporous structure. Using this technique, it has been shown that silver zeolite blended with polyolefin elution of silver at a higher concentration lasts than that simply blended with silver zeolite in polyamide. (For example, see Patent Document 6)

JP 2001-278715 A JP 62-210098 A JP-A-8-155480 JP 2006-95517 A Japanese Patent Laid-Open No. 7-222983 JP 2008-174576 A

If zeolite particles as described in Patent Document 1 are added to water as they are, they cannot withstand long-term use, no matter how hard the particles are cured. In addition, the silver concentration is not stable due to large fluctuations in the elution amount of silver. On the other hand, the soluble glass as described in Patent Document 2 is also the same, and there is dissolution of glass components other than silver which is an active ingredient, and it is difficult to control the silver concentration in the aqueous solution. Even if there is little or no replacement of water, there is a problem that the glass continues to melt, and silver continues to dissolve, thereby significantly increasing the silver concentration in the treated water. For clean water such as beverage use and circulating water, it is optimal to elute only a small amount of silver ions, which are antibacterial components, and not to dissolve or dissolve other substances than necessary.
Further, in the invention described in Patent Document 3, the silver elution concentration cannot be controlled even if silver is supported on a phosphate that is not an ion exchanger capable of controlling the elution silver concentration by the balance between the antibacterial agent and the environment. Further, there is a problem that the short fiber is unwound and mixed into water.
There are also proposals using activated carbon as in Patent Document 4 and Patent Document 5. When activated carbon is used, it is black and adsorbs substances other than pollutants, which limits the application, and there is also a problem that pollutants are released into water when the activated carbon adsorption capacity is saturated.
In the invention described in Patent Document 6, since polyolefin is low in hydrophilicity, fine pores can be obtained by water treatment only in the vicinity of the very surface of the molded product. Therefore, only silver near the surface can be used. Even if initial sustainability is obtained, long-term sustainability cannot be obtained. Moreover, since the silver zeolite has large pores and the ability to control ion exchange cannot be said to be precise, it cannot be said that the concentration of eluted silver can be strictly controlled.
In this way, it is possible to develop antibacterial properties in a short period of time, but it is not easy to control long-term sustainability and constant silver concentration in water, and the technology of antibacterial agents suitable for water treatment is clear Not been.

  The problem of the present invention is that antibacterial treatment can be carried out by eluting silver ions at a constant concentration that is not excessive or insufficient with respect to clean water such as drinking water and circulating water, and the ability to elute silver can be maintained for a long time. It is providing the antibacterial agent for water treatment, the manufacturing method of the antibacterial agent for water treatment, and the water treatment method using the same.

The above-described problems of the present invention have been solved by the means described in <1>, <6> and <7> below. It is described below together with <2> to <5> which are preferred embodiments.
<1> JIS L 0105: The standard moisture content specified in 2006 is 1 to 10% by weight of resin, and 1 to 30% by weight of silver-substituted zirconium phosphate represented by the formula [1] as an antibacterial agent; An antibacterial treatment agent for water treatment, characterized by comprising a resin composition containing
_{Ag a M b Zr c Hf d} (PO 4) 3 · nH 2 O [1]
In the formula [1], M is at least one ion selected from the group consisting of alkali metal ions, alkaline earth metal ions, ammonium ions, hydrogen ions and oxonium ions, and a, b and c are each independent. And d is 0 or a positive number, n is 0 or a positive number of 2 or less, a, b, c and d satisfy the relationship of the formula [A], and M is monovalent In this case, the formula [B] is satisfied, and when M is divalent, the formula [C] is satisfied. 1.75 <c + d <2.25 [A] a + b + 4 (c + d) = 9 [B] a + 2b + 4 (c + d) = 9 [C],
<2> The antibacterial treatment agent for water treatment according to <1>, wherein the silver content of the silver-substituted zirconium phosphate is 4 to 13% by weight,
<3> The antibacterial treatment agent for water treatment according to <1>, wherein the treatment agent has a specific surface area of 5 to 100 cm ² / g,
<4> The antibacterial agent for water treatment according to <1>, wherein 50 to 99% by weight of the resin constituting the resin composition is a polyamide resin,
<5> The antibacterial agent for water treatment according to <4>, wherein the polyamide resin is nylon 6.
<6> The method for producing an antibacterial agent for water treatment according to any one of <1> to <5>, including a step of blending the antibacterial agent with the resin.
<7> A water treatment method including a step of bringing water into contact with the antibacterial agent for water treatment according to any one of <1> to <5>.

  According to the present invention, it is possible to elute a certain concentration of silver ions in excess or deficiency with respect to clean water such as drinking water and circulating water to perform antibacterial treatment, and to maintain silver elution ability for a long period of time. An antibacterial agent for water treatment, a method for producing an antibacterial agent for water treatment, and a water treatment method using the same can be provided.

Hereinafter, the present invention will be described in detail.
In the present invention, the description of “lower limit to upper limit” representing a numerical range represents “lower limit or higher and lower limit or lower”, and the description of “upper limit to lower limit” represents “lower limit or higher and lower limit or higher”. That is, it represents a numerical range including an upper limit and a lower limit.

(Antimicrobial agent for water treatment)
The antibacterial agent for water treatment of the present invention is a resin having a standard moisture content of 1 to 10% by weight and a specific silver-substituted zirconium phosphate represented by the following formula [1] (hereinafter also simply referred to as “silver-substituted zirconium phosphate”). .) Is made of a resin composition containing 1 to 30% by weight based on the total weight of the resin composition.
_{Ag a M b Zr c Hf d} (PO 4) 3 · nH 2 O [1]
In the above formula [1], M is at least one ion selected from the group consisting of alkali metal ions, alkaline earth metal ions, ammonium ions, hydrogen ions and oxonium ions, and a, b and c are respectively Independently a positive number, d is 0 or a positive number, n is 0 or a positive number of 2 or less, a, b, c and d satisfy the relationship of the formula [A], and M is monovalent In the case of, the formula [B] is satisfied, and in the case where M is divalent, the formula [C] is satisfied.
1.75 <c + d <2.25 [A]
a + b + 4 (c + d) = 9 [B]
a + 2b + 4 (c + d) = 9 [C]

The water treatment in the present invention refers to line washing of water (drinking water) taken directly into the living body directly or after undergoing steps such as cooking, mixing, and dissolution, circulating cooling water, various viewing waters, food chemicals, etc. It means antibacterial treatment of water (clean water) that is harmless and clean, such as water. In the present invention, antibacterial treatment is performed by eluting silver ions of a certain concentration that is not excessive or insufficient with respect to the above water. It is. The antibacterial treatment means a treatment that suppresses bacterial growth.
The antibacterial treatment agent for water treatment of the present invention can maintain a constant silver concentration according to the ion concentration contained in the water to be treated, and also has long-term silver elution persistence. Therefore, even if water is replaced by clean water such as drinking water or circulating water due to water flow or water consumption, it achieves a silver ion concentration that is not excessive or insufficient for antibacterial action in water, and for a long time. It is possible to maintain the antibacterial effect.

  The silver-substituted zirconium phosphate used in the present invention is a kind of silver-based inorganic antibacterial agent, and the zirconium phosphate serving as the skeleton is preferably a crystalline one having a three-dimensional network structure. Zirconium phosphate includes an amorphous one and a crystalline one having a two-dimensional layered structure or a three-dimensional network structure. Among these, crystalline zirconium phosphate having a three-dimensional network structure is preferable because it is excellent in heat resistance, chemical resistance, radiation resistance, low thermal expansion, etc. Among them, silver ions are preferably added to hexagonal zirconium phosphate. The silver-substituted zirconium phosphate obtained by substitution is more preferable because it exhibits not only excellent antibacterial effects but also excellent durability, ion selectivity, discoloration and safety during resin processing.

As a specific method for synthesizing the silver-substituted zirconium phosphate used in the present invention, the zirconium phosphate compound represented by the following formula [2] is used as 0.6 to a coefficient b1 of the formula [2] per mole thereof. It can be obtained by heat treatment after ion exchange using an aqueous solution containing an equivalent amount of silver nitrate multiplied by 0.99.
_{Na b1 A c1 Zr e Hf f} (PO 4) 3 · nH 2 O (2)
In Formula [2], A is an ammonium ion and / or a hydrogen ion, b1, c1, e, and f are each independently a positive number, 1.75 <(e + f) <2.25, and b1 + c1 + 4 It is a number that satisfies (e + f) = 9.

Examples of the synthesis method of the zirconium phosphate compound represented by the formula [2] include a wet method or a hydrothermal method in which various raw materials are reacted in an aqueous solution. The zirconium phosphate compound in which A in formula [2] is an ammonium ion is an aqueous solution containing a predetermined amount of a zirconium compound, ammonia or a salt thereof, oxalic acid or a salt thereof, phosphoric acid or a salt thereof, or the like. , Or “caustic soda”) or after adjusting the pH to about 1 to 4 with aqueous ammonia and then heating at a temperature of 70 ° C. or higher. Moreover, it is preferable that the said heating temperature is 200 degrees C or less.
In addition, the zirconium phosphate compound in which A in formula [2] is a hydrogen ion is an aqueous solution containing a predetermined amount of zirconium compound, oxalic acid or a salt thereof, or phosphoric acid or a salt thereof, with caustic soda and having a pH of about 1 to 4 After the adjustment, the zirconium phosphate obtained by heating at a temperature of 70 ° C. or higher is further stirred in an aqueous solution such as hydrochloric acid, nitric acid or sulfuric acid to carry hydrogen ions. Moreover, it is preferable that the said heating temperature is 200 degrees C or less.
The hydrogen ions can be supported simultaneously with the silver ions supported by silver nitrate or after the silver ions are supported. The synthesized zirconium phosphate compound is further filtered, washed with water to a predetermined electrical conductivity, dried, and lightly pulverized to obtain a white particulate zirconium phosphate compound. Moreover, if it is the hydrothermal method synthesize | combined under the pressurization over 100 degreeC, the zirconium phosphate compound represented by Formula [2] is compoundable, without using an oxalic acid or its salt.

  Zirconium compounds that can be used as a raw material for the synthesis of the zirconium phosphate compound represented by the formula [2] include water-soluble or acid-soluble zirconium salts. For example, zirconium nitrate, zirconium acetate, zirconium sulfate, basic zirconium sulfate, zirconium oxysulfate, and zirconium oxychloride are exemplified, and zirconium oxychloride is preferable in consideration of reactivity and economy.

  Hafnium compounds that can be used as a raw material for the synthesis of the zirconium phosphate compound represented by the formula [2] include water-soluble or acid-soluble hafnium salts, such as hafnium chloride, hafnium oxychloride, and hafnium ethoxide. Also exemplified are zirconium compounds containing hafnium. 0.1-5 mol% is preferable and, as for the hafnium content rate contained with respect to a zirconium compound, 0.3-4 mol% is more preferable. In the present invention, it is preferable to use zirconium oxychloride containing such a small amount of hafnium in view of reactivity, economy, and the like.

  As oxalic acid or a salt thereof that can be used as a raw material for the synthesis of the zirconium phosphate compound represented by the formula [2], oxalic acid dihydrate, sodium oxalate, ammonium oxalate, sodium hydrogen oxalate, and hydrogen oxalate Ammonium is exemplified, and oxalic acid dihydrate is preferable.

  Examples of ammonia or a salt thereof that can be used as a raw material for synthesizing the zirconium phosphate compound represented by the formula [2] include ammonium chloride, ammonium nitrate, ammonium sulfate, aqueous ammonia, ammonium oxalate, and ammonium phosphate. Ammonium chloride or aqueous ammonia.

  As phosphoric acid or a salt thereof that can be used as a raw material for the synthesis of the zirconium phosphate compound represented by the formula [2], a soluble or acid-soluble salt is preferable. Specifically, phosphoric acid, sodium phosphate, sodium hydrogen phosphate Examples thereof include ammonium hydrogen phosphate and ammonium phosphate, and phosphoric acid is more preferable. The concentration of the phosphoric acid is preferably an aqueous solution having a concentration of about 60 to 85% by weight.

  When synthesizing the zirconium phosphate compound represented by the formula [2], the molar ratio of phosphoric acid or a salt thereof to the zirconium compound (with the zirconium compound being 1) is preferably more than 1.5 and less than 2. More preferably, it is 1.51 or more and less than 1.71, More preferably, it is 1.52 or more and 1.67 or less, Especially preferably, it is 1.52 or more and 1.65 or less.

  Further, the molar ratio of phosphoric acid or a salt thereof to ammonia or a salt thereof when synthesizing zirconium phosphate represented by the formula [2] (ammonia or a salt thereof is 1) is preferably 0.3 to 10. 1 to 10 is more preferable, and 2 to 5 is particularly preferable.

The molar ratio of phosphoric acid or a salt thereof and oxalic acid or a salt thereof when synthesizing the zirconium phosphate represented by the formula [2] (with oxalic acid or a salt thereof as 1) is preferably 1 to 6, more Preferably it is 1.5-5, More preferably, it is 1.51-4, Most preferably, it is 1.52-3.5. That is, the zirconium phosphate compound represented by the formula [2] can be preferably synthesized by a wet method or a hydrothermal method containing oxalic acid or a salt thereof.
In the case of the hydrothermal method, it is not necessary to contain oxalic acid or a salt thereof. On the other hand, the wet method makes it easy to control the particle size, and it is possible to obtain crystals of a zirconium phosphate compound having a uniform particle size distribution in the median size range of 0.1 μm to 5 μm.

  The solid content concentration in the reaction slurry when synthesizing the zirconium phosphate compound represented by the formula [2] is preferably 3% by weight or more, and more preferably 7 to 20% by weight in view of efficiency such as economy. .

  The pH when synthesizing the zirconium phosphate compound represented by the formula [2] is preferably 1 or more and 4 or less, more preferably 1.3 to 3.5, and still more preferably 1.8 to 3.0. Particularly preferred is 2.0 to 3.0. For adjusting the pH, it is preferable to use sodium hydroxide, potassium hydroxide or aqueous ammonia, and sodium hydroxide is more preferably used.

  Moreover, the synthesis temperature when synthesizing the zirconium phosphate represented by the formula [2] is preferable because the higher the reaction is, the faster the reaction proceeds. It is advantageous to set the synthesis temperature low. A preferred lower limit is 70 ° C. or higher, more preferably 80 ° C. or higher, still more preferably 90 ° C. or higher, and particularly preferably 95 ° C. or higher. Moreover, as an upper limit of synthesis | combination temperature, 150 degrees C or less is preferable, More preferably, it is 120 degrees C or less.

In the synthesis of the zirconium phosphate compound represented by the formula [2], it is desirable that the raw materials are mixed homogeneously and stirred so that the reaction proceeds uniformly.
The synthesis time of the zirconium phosphate compound represented by the formula [2] varies depending on the synthesis temperature. For example, the synthesis time of the zirconium phosphate compound used in the present invention is preferably 4 hours to 72 hours, more preferably 8 hours to 72 hours, and particularly preferably 10 hours to 48 hours.

  The particle diameter of the zirconium phosphate compound represented by the formula [2] is defined as a median diameter by volume-based measurement using a laser diffraction particle size distribution meter. The median diameter of the zirconium phosphate compound represented by the formula [2] is preferably from 0.1 to 5 μm, more preferably from 0.1 to 4 μm, still more preferably from 0.2 to 3 μm, particularly preferably from 0.3 to 2 μm. In addition, considering the workability to various products, not only the median diameter but also the maximum particle diameter is important. Accordingly, the maximum particle size of the zirconium phosphate compound represented by the formula [2] is preferably 10 μm or less, more preferably 6 μm or less, and particularly preferably 4 μm or less. The lower limit is preferably 0.1 μm or more.

Specific examples of the zirconium phosphate compound represented by the formula [2] that can be used as a raw material for the silver-substituted zirconium phosphate used in the present invention include the following.
Na _0.07 (NH ₄ ) _0.85 Zr _2.0 Hf _0.02 (PO ₄ ) ₃ · 0.65H ₂ O
Na _0.12 (NH ₄ ) _0.65 Zr _2.01 Hf _0.03 (PO ₄ ) ₃ · 0.85H ₂ O
Na _0.19 (NH ₄ ) _0.65 Zr _2.03 Hf _0.01 (PO ₄ ) ₃ · 0.75H ₂ O
Na _0.21 (NH ₄ ) _0.75 Zr _1.99 Hf _0.02 (PO ₄ ) ₃ · 0.6H ₂ O
Na _0.27 (NH ₄ ) _0.75 Zr _1.92 Hf _0.15 (PO ₄ ) ₃・ 0.75H ₂ O
Na _0.29 (NH ₄ ) _0.55 Zr _1.92 Hf _0.05 (PO ₄ ) ₃ · 0.5H ₂ O
Na _0.57 (NH ₄ ) _0.55 Zr _1.95 Hf _0.02 (PO ₄ ) ₃ · 0.35H ₂ O
Na _0.70 (NH ₄ ) _0.85 Zr _1.99 Hf _0.01 (PO ₄ ) ₃ · 0.4H ₂ O
Na _0.07 H _0.85 Zr _2.0 Hf _0.02 (PO ₄ ) ₃ · 0.65H ₂ O
Na _0.12 H _0.65 Zr _2.01 Hf _0.03 (PO ₄ ) ₃ · 0.85 H ₂ O
Na _0.19 H _0.65 Zr _2.03 Hf _0.01 (PO ₄ ) ₃ · 0.75H ₂ O
Na _0.21 H _0.75 Zr _1.99 Hf _0.02 (PO ₄ ) ₃ · 0.6H ₂ O
Na _0.27 H _0.75 Zr _1.92 Hf _0.15 (PO ₄ ) ₃・ 0.75H ₂ O
Na _0.29 H _0.55 Zr _1.92 Hf _0.05 (PO ₄ ) ₃ · 0.5H ₂ O
Na _0.57 H _0.55 Zr _1.95 Hf _0.02 (PO ₄ ) ₃ · 0.35H ₂ O
Na _0.70 H _0.85 Zr _1.99 Hf _0.01 (PO ₄ ) ₃ · 0.4H ₂ O

  The silver-substituted zirconium phosphate of the formula [1] can be obtained by heat-treating these zirconium phosphate compounds after silver ion exchange. The method for silver ion exchange is to immerse the zirconium phosphate compound in an aqueous solution containing silver nitrate. It is preferable to increase the silver nitrate content of the above aqueous solution because it is difficult for the resulting silver-based inorganic antibacterial agent to discolor when used in a resin. This is economically undesirable. It is preferable to use an aqueous solution containing a molar amount of silver nitrate obtained by multiplying the coefficient b1 of the formula [2] by 0.6 to 0.99, per mole of the zirconium phosphate compound represented by the formula [2]. It is preferable to use an aqueous solution containing a molar amount of silver nitrate obtained by multiplying the coefficient b1 of the formula [2] by 0.7 to 0.98 per mole of zirconium phosphate. The amount of the zirconium phosphate compound immersed in the aqueous silver nitrate solution is not particularly limited as long as it can be uniformly mixed with the aqueous solution. Specifically, the zirconium phosphate compound represented by the formula [2] It is preferable that it becomes 20 weight% or less of.

  For the adjustment of the aqueous solution containing silver ions, it is preferable to use an aqueous solution in which silver nitrate is dissolved in deionized water. It is preferable that the temperature of the aqueous solution at the time of ion exchange is 0-100 degreeC, More preferably, it is 20-80 degreeC. Since this ion exchange is performed promptly, the immersion time can be within 5 minutes, but 30 minutes to 5 hours is preferable in order to obtain a uniform and high silver ion exchange rate. After completion of the silver ion exchange, it is preferably washed with deionized water or the like. Washing with water is preferably carried out until the electrical conductivity of the filtrate is measured and is 500 μS or less. After washing with water, the silver-based inorganic antibacterial agent represented by the formula [1] can be obtained by filtration and drying, and further heat treatment at an appropriate temperature.

  In the formula [1], a represents the silver content. When the value of a is small, the silver content in the silver-substituted zirconium phosphate is low, and when the value of a is large, the silver content is high. A higher silver content is preferred because of improved sustainability.

  On the other hand, silver ions are unstable with respect to heat and light exposure, and there is a problem in long-term stability, such as causing coloration by being immediately reduced to metallic silver. Even in the case of zirconium phosphate capable of stably supporting silver ions, the high silver content needs to be adjusted to an appropriate silver content because of concerns such as discoloration and productivity. Further, since the silver content in zirconium phosphate varies depending on the type and ratio of other components, the value of a is more easily controlled by controlling the silver content rather than the value of a. The silver content in the preferred silver-substituted zirconium phosphate is 2 to 15% by weight, more preferably 4 to 13% by weight, and particularly preferably 6 to 12% by weight. In addition, the preferable value of a at this time is 0.05 or more and 0.7 or less.

  In the formula [1], c and d are numbers satisfying 1.75 <c + d <2.25 and a + b + 4 (c + d) = 9. c is preferably larger than 1.75 and not larger than 2.1, more preferably not smaller than 1.85 and not larger than 2.07, still more preferably not smaller than 1.9 and not larger than 2.03. Moreover, d is 0.005-0.2, Preferably it is 0.01-0.2, More preferably, it is 0.015-0.15.

  In Formula [1], b is 0.01-2, Preferably it is 0.01-1.95.

  In Formula [1], M may be included in one or more types, preferably 1 to 5 types, and more preferably 1 to 3 types. Preferable examples of M include sodium ion, potassium ion, lithium ion, magnesium ion, zinc ion, ammonium ion, hydrogen ion and oxonium ion.

  In the formula [1], n is preferably 1 or less, more preferably 0.01 to 0.5, and particularly preferably 0.03 to 0.3. When n is larger than 2, the absolute amount of water contained is large, and foaming or hydrolysis may occur during heating when blended in various materials.

  These silver-substituted zirconium phosphates are preferably obtained as white fine-particle crystals and have a median diameter of 0.1 to 30 μm measured on a volume basis by a laser particle size distribution meter. More preferably, it is 0.1-4 micrometers, More preferably, it is 0.2-3 micrometers, Most preferably, it is 0.3-2 micrometers. In addition, considering the workability to various products, not only the median diameter but also the maximum particle diameter is important. Accordingly, the maximum particle size of the zirconium phosphate compound represented by the formula [2] is preferably 10 μm or less, more preferably 6 μm or less, and particularly preferably 4 μm or less. The lower limit is preferably 0.1 μm or more.

  The silver-substituted zirconium phosphate used in the present invention has a higher retention of silver ions than many other carriers, and therefore the release of silver ions into clean water having a low ion concentration tends to be reduced. Since silver ions are easy to release in contaminated water with high ion concentration, the release amount of silver ions is automatically adjusted according to the degree of water contamination, and the antibacterial effect is long-lasting. There is a feature that discoloration due to ion emission hardly occurs.

  The silver-substituted zirconium phosphate in the present invention is preferably highly crystalline. The crystallinity of silver-substituted zirconium phosphate can be determined by the peak intensity resulting from the silver-substituted zirconium phosphate crystal by powder X-ray diffraction. The peak intensity at about 2θ = 20.2 °, which is a peak attributed to hexagonal zirconium phosphate detected when measured with CuKα rays under measurement conditions of 50 kV / 120 mA by powder X-ray diffraction analysis, is 1,500 cps or more. Preferably, it is 2,000 cps or more, particularly preferably 2,500 cps or more. The higher the peak intensity, the higher the crystallinity and the higher the silver ion retention, so that discoloration due to the liberation of silver ions can be prevented.

  The silver-substituted zirconium phosphate used in the present invention is preferably highly pure. The purity of the silver-substituted zirconium phosphate can be confirmed by confirming the presence or absence of an impurity peak other than the peak due to the silver-substituted zirconium phosphate crystal by powder X-ray diffraction, and confirming the content of the component by fluorescent X-ray analysis. The total of components derived from silver-substituted zirconium phosphate detected by fluorescent X-ray analysis is preferably 96% or more and 100% or less, and more preferably 99% or more and 100% or less.

Specific examples of the silver-substituted zirconium phosphate used in the present invention can be exemplified below.
Ag _0.05 Na _0.22 H _0.1 (H ₃ O) _0.55 Zr _2.0 Hf _0.02 (PO ₄ ) ₃ · 0.15H ₂ O
Ag _0.17 Na _0.32 H _0.35 Zr _2.03 Hf _0.01 (PO ₄ ) ₃ · 0.05H ₂ O
Ag _0.17 Na _0.64 H _0.33 Zr _1.92 Hf _0.05 (PO ₄ ) ₃ · 0.15H ₂ O
Ag _0.45 Na _0.47 H _0.2 Zr _1.95 Hf _0.02 (PO ₄ ) ₃・ 0.05H ₂ O
Ag _0.55 Na _0.1 H _0.2 (H ₃ O) _0.15 Zr _1.99 Hf _0.01 (PO ₄ ) ₃ · 0.15H ₂ O
Ag _0.05 Na _0.32 (NH ₄ ) _0.2 H _0.35 Zr _2.0 Hf _0.02 (PO ₄ ) ₃ · 0.15H ₂ O
Ag _0.10 Na _0.21 H _0.28 (H ₃ O) _0.25 Zr _2.01 Hf _0.03 (PO ₄ ) ₃ · 0.10H ₂ O
Ag _0.17 Na _0.20 Li _0.15 H _0.3 Zr _1.92 Hf _0.10 (PO ₄ ) ₃ · 0.15H ₂ O
Ag _0.17 Na _0.10 Mg _0.10 H _0.25 Zr _1.92 Hf _0.15 (PO ₄ ) ₃ · 0.15H ₂ O
Ag _0.17 Zn _0.20 Na _0.25 H _0.3 Zr _1.92 Hf _0.05 (PO ₄ ) ₃ · 0.15H ₂ O
Ag _0.45 Na _0.27 K _0.1 H _0.3 Zr _1.95 Hf _0.02 (PO ₄ ) ₃・ 0.05H ₂ O
Ag _0.55 K _0.1 H _0.1 (H ₃ O) _0.25 Zr _1.99 Hf _0.01 (PO ₄ ) ₃ · 0.15H ₂ O

An antibacterial resin composition can be easily obtained by blending the silver-substituted zirconium phosphate used in the present invention with a resin. The method for producing an antibacterial treatment agent for water treatment according to the present invention includes a step of blending the antibacterial agent with the resin. As a processing method for blending silver-substituted zirconium phosphate into a resin to obtain an antibacterial resin molded product, any known method can be adopted, and examples include the following four production methods (1) to (4). .
(1) A method of directly mixing a pellet-like resin or a powder-like resin with a mixer using an additive for facilitating adhesion between the silver-substituted zirconium phosphate and the resin and a dispersant for improving dispersibility.
(2) A method in which the mixture is mixed as described above and formed into a pellet form with an extrusion molding machine, and then the formed product is blended with the pellet-shaped resin.
(3) A method in which the silver-substituted zirconium phosphate is molded into a high-concentration pellet using wax, and then the pellet-shaped molded product is blended with the pellet-shaped resin.
(4) A method of blending this paste into a pellet-shaped resin after preparing a paste-like composition in which silver-substituted zirconium phosphate is dispersed and mixed in a highly viscous liquid such as polyol.

  Among these methods, when a hydrophilic substance such as a dispersant or a polyol is used, the hydrophilic substance in the resin composition is preferably more than 0% by weight and less than 5%, more preferably 0% by weight. More than 1% by weight. In the present invention, it is essential to use a resin having a certain standard moisture content. However, when other hydrophilic substances are used in combination, the hydrophilicity of the resin composition becomes too high, and the amount of elution of silver becomes too high. This is because the sex component may be eluted first and change the physical properties of the treatment agent.

  The compounding quantity of the silver substituted zirconium phosphate in the present invention in the resin composition is 1 to 30% by weight based on the total weight of the resin composition. A higher blending amount is preferable from the viewpoint of control of silver elution concentration in water and high sustainability, but a smaller blending amount is preferable in terms of dispersibility and ease of processing when kneaded into a resin. The preferred blending amount is 2 to 25% by weight, more preferably 3 to 20% by weight.

  There is no restriction | limiting in the shaping | molding method for processing the antibacterial agent for water treatment of this invention, The existing method and apparatus can be used. Examples thereof include injection molding (machine), extrusion molding (machine), blow molding (machine), and hot press molding (machine). Among these, injection molding (machine) is preferable because of its low thermal history in addition to the stability of the shape. This is because the heat history is less when the heat history is smaller, and the decomposition component of the resin is less likely to be dissolved in water.

The standard moisture content of the resin used in the antibacterial treatment agent for water treatment of the present invention is the same definition as the official moisture content defined in JIS L 0105: 2006, which is a general rule for physical test methods for textile products, that is, in an absolutely dry state (test The weight of the piece in a hot air dryer at 105 ° C plus or minus 2 ° C and a constant weight) and the standard state (temperature 20 ° C plus or minus 2 ° C, relative humidity 65% plus or minus 4%) The difference from the weight of the test piece that became a constant weight was expressed as a percentage based on the weight of the above-mentioned dry state as the standard moisture content, and the official moisture content of the fiber in Table 1 of JIS L 1030-2: 2005 Both can be used with the same definition.
The higher the standard moisture content of the resin used in the present invention, the more silver is eluted and the antibacterial effect tends to be manifested. However, when the amount is too much, the problem of discoloration tends to occur. On the other hand, the lower the water content, the lower the elution amount and the less antibacterial effect, but the risk of discoloration is reduced. This effect is greatly influenced by the antibacterial agent to be combined. The resin used in the present invention has a water content of 1.0% by weight to 10% by weight, preferably 2% by weight to 9% by weight, more preferably 3% by weight to 8.5% by weight, and particularly preferably 4 wt% or more and 8 wt% or less.

As a standard moisture content of a general resin, polypropylene 0.0, polyethylene 0.0, vinyl chloride 0.0, vinylidene 0.0, polyester 0.3 to 0.4, urethane 1, acrylic 1.2 to 2. 0, polyacetal 2.0, polyamide 3.5-5.0, acetate 6-7, rayon 12-14, and the most preferred resin from the value of standard moisture content is polyamide. Polyamide is generally called nylon, and there are nylon 6, 66, 46, MDX6, 61, 9T, 610, 612, 11, 12, etc., which can be used alone or in combination. . Among these, nylon 6 is particularly preferable from the viewpoint of versatility, moldability, controllability of silver elution amount, and the like, and can be used by mixing with other types of nylon. % Or less is preferred. Furthermore, among the same resins, the lower the density, the easier it is to elute.
The density of the resin is known to affect the hardness of the resin and the like. The standard value of the standard resin density is 0.90 to 0.91 for polypropylene and 0.92 to 0.001 for polyethylene. 93, 1.30 to 1.35 for vinyl chloride, 1.12 to 1.14 for nylon, 1.20 for urethane, 1.17 to 1.2 for acrylic, 1.42 for polyacetal, etc. However, including these ranges, it has been found that the same resin has a tendency that silver having a high density is less likely to elute and silver having a lower density tends to elute.

  In addition, a resin whose standard moisture content is not in the range of 1.0 to 10 as long as the effect of the present invention is not impaired can be used in combination. The degree that does not impair the effect is preferably 40% by weight or less, more preferably 20% by weight or less, and particularly preferably 10% by weight or less of the total amount of the resin used.

  For the antibacterial agent for water treatment of the present invention, a dispersant such as metal soap can be used. A preferred dispersant is a metal soap, such as zinc stearate, calcium stearate, magnesium stearate, and more preferably magnesium stearate.

  The resin composition used for the antibacterial treatment agent for water treatment of the present invention can be mixed with various additives as necessary in order to improve kneading into the resin and other physical properties. Specific examples include pigments such as zinc oxide and titanium oxide, inorganic ion exchangers such as zirconium phosphate and zeolite, dyes, antioxidants, light-resistant stabilizers, flame retardants, antistatic agents, foaming agents, impact-strengthening agents, Lubricant such as glass fiber, metal soap, moisture proof agent, extender, coupling agent, nucleating agent, fluidity improver, deodorant, wood powder, antifungal agent, antifouling agent, rust preventive agent, metal powder, UV There are absorbers and ultraviolet shielding agents. However, since it is used for antibacterial treatment of clean water, it is preferable that these additives are not contained as much as possible.

  In the antibacterial treatment agent for water treatment of the present invention, any known processing technique and machine can be used in accordance with the characteristics of various resins, and mixing, mixing or mixing while heating and pressurizing or depressurizing at an appropriate temperature or pressure. They can be easily prepared by a kneading method, and their specific operation may be performed by a conventional method. The shape is not limited, and can be formed into various forms such as a spherical shape, a lump shape, a sponge shape, a film shape, a plate shape, a thread shape, a pipe shape, or a composite thereof, and can be appropriately designed according to the application. it can.

The specific surface area of the molded article of the antibacterial agent for water treatment in the present invention is that the larger the silver elution rate is, the more the dissolved silver concentration is obtained, and the deep antibacterial agent far from the water contact surface is sufficient. This is preferable because there is no fear that it will not be used. On the other hand, those having a small specific surface area are preferable because they are thick and have high strength, so there is no fear of deformation and overlapping. Therefore, the specific surface area of the water treatment antibacterial treatment agent in the present invention is preferably 3~110cm ² / g, preferably from 5 to 100 cm ² / g. The specific surface area can be calculated using the dimensions of the treatment agent as shaped bodies, for example, to obtain a surface area of 3cm ² / g~50cm ² / g, with a radius 0.05cm~1cm about if a sphere In the case of a 10 cm square plate, the average thickness is about 0.3 mm to 6 mm. In addition, when the specific surface area is increased, the installation area becomes larger in the planar shape, so interference may occur depending on the shape of the water flow cartridge, etc. It can also be used as a molded article of a preferable design that does not impair the quality.

The water treatment method of the present invention includes a step of bringing the antibacterial agent for water treatment into contact with water.
There is no restriction | limiting in particular in the usage form of the antibacterial agent for water treatment of this invention, You may use it as it is, pack it in a mesh, a nonwoven fabric, etc., or you may fill a cartridge-like container. The antibacterial treatment agent can be used by immersing the antibacterial treatment agent in water to be treated or by passing water to be treated through a container containing the antibacterial treatment agent. The antibacterial treatment agent need not always be present in water, and once it is dried in air, its performance does not change greatly if it is returned to water again. What is necessary is just to adjust the standard of the usage-amount of an antimicrobial treatment agent suitably with silver content or the target antimicrobial effect. The silver elution amount when the antibacterial treatment agent for water treatment in the present invention is immersed or passed through the target clean water is preferably 5 ppb or more and 200 ppb or less, more preferably 10 ppb or more and 100 ppb or less. It is preferable that the concentration in this range be maintained for 3 weeks or more, and if possible, about 1 year. Note that ppb is the weight ppb.
For example, when used in immersing the treating agent the preferred silver elution amount by using 50cm ² ~500cm ² about water treatment antibacterial agent in a surface area to 1L water is obtained. Since the water contact time is shorter than the immersion, the surface area is preferably several times to 10 times the immersion when used in water flow.

  The use of the antibacterial agent for water treatment of the present invention is not particularly limited, and can be effectively used for water treatment for water in which microbial contamination is a problem. For example, filter media for water purifiers, water tanks for water servers, circulating water, water for cut flowers, water pipes and tanks, pools and ponds, water for ice production in refrigerators, humidifiers, air conditioning drain water, and the like.

EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to this.
The median diameter of the particles was measured on a volume basis using a laser diffraction particle size distribution.
The amount of zirconium contained in the antibacterial agent and its raw material was calculated by dissolving the specimen using a strong acid and measuring the liquid with an inductively coupled plasma (ICP) emission spectrometer. The amount of phosphorus was calculated by dissolving the sample using a strong acid and then measuring this solution with an ICP emission spectrometer. The amount of sodium was calculated by dissolving the specimen with a strong acid and measuring the liquid with an atomic absorption photometer. The amount of ammonia was calculated by dissolving the sample using a strong acid and measuring this solution by the indophenol method. The amount of oxonium ions was calculated by measuring the weight loss of 160 to 190 ° C. by thermal analysis. The diffraction intensity of the X-ray powder diffractometry (XRD) is an X-ray diffraction intensity measured with Cuα rays under the condition of X-ray 50 kV / 120 mA with a powder XRD diffractometer. The number of bacteria was measured by a culture method at 37 ° C. for 2 days by a pour culture method using a normal agar medium. The silver elution concentration was measured with an ICP emission spectrometer.

<Antimicrobial agent A: Preparation of silver-substituted zirconium phosphate (A)>
Dissolve 0.1 mol of oxalic acid dihydrate, 0.2 mol of zirconium oxychloride octahydrate containing 0.17% hafnium and 0.1 mol of ammonium chloride in 300 ml of deionized water, and then add 0 phosphoric acid with stirring. .3 moles were added. The solution was adjusted to pH 2.6 using 20% aqueous sodium hydroxide solution and stirred at 98 ° C. for 14 hours. Thereafter, the resulting precipitate was washed with deionized water and dried at 120 ° C. for 4 hours to synthesize a zirconium phosphate compound.
When the amount of each component of the zirconium phosphate compound was measured, the composition formula was as follows.
Na _0.6 (NH ₄ ) _0.4 Zr _1.98 Hf _0.02 (PO ₄ ) ₃ · 0.09H ₂ O
450 ml of an ion exchange aqueous solution in which 0.05 mol of silver nitrate was dissolved was added to 0.09 mol of the obtained zirconium phosphate, and silver was supported by stirring at 60 ° C. for 2 hours. The slurry after the silver loading treatment was filtered and washed with water, and washed with deionized water until the electrical conductivity of the filtrate reached 70 μS. Furthermore, this dried product was crushed after heat treatment at 650 ° C. for 12 hours using an electric furnace to obtain silver-substituted zirconium phosphate (A).
The silver-substituted zirconium phosphate (A) had a median diameter of 1.0 μm and a silver content of 10.2% by weight. The composition formula obtained by measuring the amount of each component was as follows.
Ag _0.5 Na _0.1 H _0.4 Zr _1.98 Hf _0.02 (PO ₄ ) ₃

<Antimicrobial agent B: Preparation of silver-substituted zirconium phosphate (B)>
Dissolve 0.1 mol of oxalic acid dihydrate, 0.19 mol of zirconium oxychloride octahydrate containing 0.18% hafnium and 0.10 mol of ammonium chloride in 300 ml of deionized water, and then add 0 phosphoric acid with stirring. .3 moles were added. The solution was adjusted to pH 2.7 using a 20% aqueous sodium hydroxide solution and then stirred at 98 ° C. for 14 hours. Thereafter, the resulting precipitate was thoroughly washed with deionized water and dried at 120 ° C. to synthesize a zirconium phosphate compound.
When the amount of each component of this zirconium phosphate compound was measured, the composition formula was as follows.
Na _0.5 (NH ₄ ) _0.8 Zr _1.91 Hf _0.015 (PO ₄ ) ₃ · 0.11H ₂ O
450 ml of 1N aqueous nitric acid solution in which 0.019 mol of silver nitrate was dissolved in 0.09 mol of the obtained zirconium phosphate compound was added and stirred at 60 ° C. for 2 hours to carry silver. Thereafter, the sample was thoroughly washed with deionized water and dried at 120 ° C. for 4 hours at 670 ° C. for high temperature heating. After lightly pulverizing the powder after the high-temperature heat treatment, it was allowed to stand for 6 hours in an atmosphere of 50% humidity and 110 ° C., and then subjected to moisture absorption treatment to obtain silver-substituted zirconium phosphate (B).
The median diameter of this silver-substituted zirconium phosphate (B) was 0.8 μm, the silver content was 4.2% by weight, and the composition formula obtained by measuring the amount of each component was as follows.
Ag _0.19 Na _0.37 H _0.21 (H ₃ O) _0.43 Zr _1.91 Hf _0.015 (PO ₄ ) ₃ · 0.19H ₂ O

<Antimicrobial agent C: Preparation of silver-substituted zirconium phosphate (C)>
After dissolving 0.195 mol of zirconium oxychloride octahydrate containing 0.18% hafnium and 0.12 mol of ammonium chloride in 300 ml of deionized water, 0.3 mol of phosphoric acid was added with stirring. The solution was adjusted to pH 2.7 using a 20% aqueous sodium hydroxide solution and then stirred at 140 ° C. under saturated vapor pressure for 4 hours. Thereafter, the resulting precipitate was thoroughly washed with deionized water and dried at 120 ° C. to synthesize a zirconium phosphate compound.
When the amount of each component of the zirconium phosphate compound was measured, the composition formula was as follows.
Na _0.35 (NH ₄ ) _0.85 Zr _1.93 Hf _0.02 (PO ₄ ) ₃ · 0.09H ₂ O
Met.
Silver was supported by adding it to 450 ml of ion-exchanged water in which 0.014 mol of silver nitrate was dissolved in 0.09 mol of the obtained zirconium phosphate and stirring at 60 ° C. for 2 hours. Thereafter, the sample was thoroughly washed with deionized water and dried at 120 ° C. and subjected to high-temperature heat treatment at 700 ° C. for 4 hours to obtain silver-substituted zirconium phosphate (C).
The median diameter of this silver-substituted zirconium phosphate (C) was 0.8 μm, the silver content was 3.1% by weight, and the composition formula obtained by measuring the amount of each component was as follows.
Ag _0.14 Na _0.24 H _0.46 Zr _2.03 Hf _0.02 (PO ₄ ) ₃

<Antimicrobial agent D: Preparation of silver-substituted zirconium phosphate (D)>
After dissolving 0.195 mol of zirconium oxychloride octahydrate containing 0.18% hafnium and 0.12 mol of ammonium chloride in 300 ml of deionized water, 0.3 mol of phosphoric acid was added with stirring. The solution was adjusted to pH 2.7 using a 20% aqueous sodium hydroxide solution and then stirred at 140 ° C. under saturated vapor pressure for 4 hours. Thereafter, the resulting precipitate was thoroughly washed with deionized water and dried at 120 ° C. to synthesize a zirconium phosphate compound.
When the amount of each component of the zirconium phosphate compound was measured, the composition formula was as follows.
NaZr _1.985 Hf _0.015 (PO ₄ ) ₃ · 0.09H ₂ O
Met.
Silver was supported by adding to 450 ml of ion-exchanged water in which 0.08 mol of silver nitrate was dissolved in 0.09 mol of the obtained zirconium phosphate and stirring at 60 ° C. for 2 hours. Thereafter, it was thoroughly washed with deionized water and dried at 120 ° C. and subjected to high-temperature heat treatment at 700 ° C. for 4 hours to obtain silver-substituted zirconium phosphate (D).
When the amount of each component of the silver-substituted zirconium phosphate (D) was measured, the composition formula was as follows.
Ag _0.79 Na _0.11 H _0.28 Zr _1.985 Hf _0.015 (PO ₄ ) ₃
The silver-substituted zirconium phosphate (D) had a median diameter of 1.0 μm and a silver content of 15.3% by weight.

<Antimicrobial agent E: Preparation of zeolitic silver-based inorganic antimicrobial agent (E)>
100 ml of an ion exchange aqueous solution in which 1.4 g of silver nitrate was dissolved in 20 g of a commercially available A-type zeolite was added, and silver was supported by stirring at 60 ° C. for 2 hours. When the zeolite-based silver-based inorganic antibacterial agent (E) obtained by drying at 120 ° C. after water washing was crushed, the median diameter was 4 μm and the silver content was 4.2% by weight.

<Antimicrobial agent F: Preparation of zeolitic silver-based inorganic antimicrobial agent (F)>
100 ml of an ion exchange aqueous solution in which 3.6 g of silver nitrate was dissolved in 20 g of commercially available A-type zeolite was added, and silver was supported by stirring at 60 ° C. for 2 hours. When the zeolite-based silver-based inorganic antibacterial agent (F) obtained by drying at 120 ° C. after water washing was crushed, the median diameter was 4 μm and the silver content was 10.2% by weight.

<Antimicrobial agent G: Preparation of silver glass-based antimicrobial agent (G)>
A glass raw material was prepared so as to be Ag ₂ O (2% by weight), K ₂ O (7% by weight), B ₂ O ₃ (45% by weight), and SiO ₂ (46% by weight). Melted by heating. After melting, it is cooled using a metal cooling molding roller, and the resulting glass is crushed by simple hitting and further dry-crushed by a ball mill. Then, the median diameter is 9 μm and the silver content is 1. 9% by weight of a silver glass antibacterial agent (G) was obtained.

<Examples 1-9 and Comparative Examples 1-9>
Various silver-based inorganic antibacterial agents A to G obtained by the above-described method were blended in various resins as shown in Table 1 and molded to prepare antibacterial treatment agents of Examples 1 to 9 and Comparative Examples 1 to 9. For the resin, nylon 6 having a standard moisture content of 4.4% by weight (trade name 1011FB manufactured by Ube Industries, Ltd.), nylon 66 having a standard moisture content of 3.9% by weight (trade name 2020B manufactured by Ube Industries, Ltd.), standard Polyacetal resin with a moisture content of 1.8% by weight (trade name Duracon manufactured by Polyplastics Co., Ltd.), acrylic resin with a standard moisture content of 1.4% by weight (trade name Acrypet manufactured by Mitsubishi Rayon Co., Ltd.), standard moisture content 0 Various antibacterial powders were prepared using 0.0% by weight polypropylene resin (trade name J105G manufactured by Prime Polypro Co., Ltd.) and a polyester resin having a standard moisture content of 0.3% by weight (trade name NEH-2030 manufactured by Unitika Co., Ltd.). Molded directly after mixing with resin pellets. In the case of plate molding, if a 10 cm square plate is formed using an injection molding machine, the specific surface area (calculated from the dimensions) is about 14 cm ² / g for a plate with a thickness of 1 mm, and the ratio for a plate with a thickness of 4 mm. When the surface area was about 3 cm ² / g and the thickness was 0.15 mm, the specific surface area was about 110 cm ² / g. The pellets were formed into a cone having a diameter of 4 mm and a height of 1 mm using a hot cut extruder. The combination of the resin type and the antibacterial agent, the blending ratio of the antibacterial agent, the shape of the treatment agent, and the specific surface area of the treatment agent are shown in Table 1. However, in Comparative Examples 8 and 9, significant foaming and discoloration occurred, and the molding itself could not be performed. Therefore, the specific surface area was not measured, and a test using a subsequent treatment agent was not performed.

（表中、−は測定していないことを示す。）

(In the table,-indicates that measurement is not performed.)

<Antimicrobial treatment evaluation using natural water for beverages>
The antibacterial treatment agent for water treatment obtained in Examples 1 to 9 and Comparative Examples 1 to 7 was added with commercially available natural water for beverages (hereinafter referred to as natural water) and sodium nitrate to adjust the Na concentration in natural water to 500 ppm. 30 g of each was immersed in 1 L of the water, and the silver concentration in the water after storage for 1 day at a water temperature of about 15 ° C. was measured. Moreover, with respect to natural water, the water concentration after the storage for 21 days was measured in the same manner after storing for 21 days and replacing only water every day. The results of the elution silver concentration measured by ICP emission analysis are shown in Table 2.

  In Examples 1 to 9, the silver concentration after 1 day was all 5 ppb or more, and there was no significant increase or decrease in silver concentration even after 21 days regardless of whether water was replaced or not. Show. The meaning of the dissolution test with Na concentration as high as 500 ppm is that ion exchange between Na ions and silver ions occurs rapidly. Therefore, elute silver ions that can be eluted from the test piece and measure the concentration. For example, based on the idea that the amount of silver that can be eluted is reflected, the test piece that obtained a high silver concentration in this test has a high level of silver that can be dissolved. Can be determined to be high.

On the other hand, Comparative Examples 1 to 3 have a small amount of elution after one day and require time to reach a silver concentration at which an antibacterial effect can be obtained. In addition, Comparative Examples 1, 2 and 4 show that the silver concentration is lowered by water replacement, and therefore the sufficient silver concentration at which an antibacterial effect can be obtained is not reached under the condition that water is exchanged.
In Comparative Examples 3 to 6, since the silver concentration was low even under the condition where the Na concentration was 500 ppm, the amount of silver that can be eluted is small, and sustainability cannot be expected.
In Comparative Example 7, since the silver concentration after 21 days without water replacement is higher than necessary, discoloration due to the silver ion concentration being too high is observed, and a certain concentration of silver ions that are not excessive or insufficient can be eluted. could not.

<Evaluation of long-term life>
In addition, in order to investigate the long-term life, in the two types of Examples 3 and 4, the test for replacing water every day was extended to 90 days. Then, the silver concentration in water on the 90th day was 13 ppb in Example 3 and 24 ppb in Example 4, which was higher in Example 4 than in Example 3 as reversed from Day 1 and Day 21. This result shows that Example 4 is superior to Example 3 in that the amount of elution of silver at the initial stage is small, but the concentration fluctuation is smaller and the elution is longer for a longer period.

<Evaluation of water flow treatment using industrial water>
100 g of each of the test pieces of Examples 3 and 4 and Comparative Examples 1, 3, and 7 was filled in a water purifier cartridge, and the number of general bacteria was about 100 / ml on average, and industrial water with a water temperature of about 15 ° C. was 0.1 Water was passed at a liter / minute. Table 3 shows the results of measurement of the number of general bacteria in 1 ml of industrial water 10 minutes after passing water and one day later by the pour culture method using a normal agar medium and the result of measuring the eluted silver concentration by ICP emission spectrometry. It was shown to.

（−は測定しなかったことを示す。）

(-Indicates that measurement was not performed.)

  In Examples 3 and 4, the antibacterial effect was confirmed after 10 minutes and 1 day, and the silver elution concentration was confirmed to be stable. On the other hand, in Comparative Examples 1, 3, and 7, the antibacterial effect after 1 day and the silver elution concentration were clearly reduced as compared with 10 minutes later. Since the molded body used in Comparative Example 7 shows the property that silver continues to elute regardless of ion exchange, the evaluation of the water replacement method shown in Table 2 shows that even if the concentration reached a high concentration, The result of continuing elution was observed. On the other hand, in the test results of Table 3 for evaluating water flow treatment, the elution rate of silver with respect to water flow was not high, so the silver concentration after 10 minutes was not so high, and the elution rate was further lowered after 1 day. I understand.

  The antibacterial agent for water treatment of the present invention can maintain a constant silver concentration and has long-term sustainability. Therefore, with respect to clean water such as drinking water and circulating water, even if water is replaced due to water flow or consumption, the constant amount of silver ions in the water, which is the required amount, is adjusted, and the antibacterial effect is maintained over a long period of time. Is possible.

Claims (7)

A resin composition comprising a resin having a standard moisture content of 1 to 10% by weight as defined in JIS L 0105: 2006, and 1 to 30% by weight of a silver-substituted zirconium phosphate represented by the formula [1] as an antibacterial agent An antibacterial treatment agent for water treatment, characterized by comprising a product.
_{Ag a M b Zr c Hf d} (PO 4) 3 · nH 2 O [1]
In the formula [1], M is at least one ion selected from the group consisting of alkali metal ions, alkaline earth metal ions, ammonium ions, hydrogen ions and oxonium ions, and a, b and c are each independent. And d is 0 or a positive number, n is 0 or a positive number of 2 or less, a, b, c and d satisfy the relationship of the formula [A], and M is a monovalent In the case, the formula [B] is satisfied, and in the case where M is divalent, the formula [C] is satisfied.
1.75 <c + d <2.25 [A]
a + b + 4 (c + d) = 9 [B]
a + 2b + 4 (c + d) = 9 [C]   The antibacterial agent for water treatment according to claim 1, wherein the silver content of the silver-substituted zirconium phosphate is 4 to 13% by weight. The antibacterial agent for water treatment according to claim 1 or 2, wherein the specific surface area of the treatment agent is 5 to 100 cm ² / g.   The antibacterial agent for water treatment according to any one of claims 1 to 3, wherein 50 to 100% by weight of the resin constituting the resin composition is a polyamide resin.   The antibacterial treatment agent for water treatment according to claim 4, wherein the polyamide resin is nylon 6.   The manufacturing method of the antibacterial agent for water treatment as described in any one of Claim 1 to 5 including the process of mix | blending the said antibacterial agent with the said resin.   A water treatment method comprising a step of bringing the antibacterial agent for water treatment according to any one of claims 1 to 5 into contact with water.