JP2010235509A - Microorganism controlling agent and microorganism controlling method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a microorganism controlling agent having a high microorganism controlling capability even in a low concentration while maintaining its effect, and a microorganism controlling method. <P>SOLUTION: The microorganism controlling agent includes, as the active components, poly[oxyethylene(dimethyliminio)ethylene(dimethyliminio)ethylene dichloride] and/or poly(2-hydroxypropyldimethylammonium chloride) and 2-methyl-4-isothiazoline-3-one. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a microbial control agent and a microbial control method for aqueous water such as an open circulation cooling water system.

  As a microorganism control agent in an open circulating cooling water system, particularly as a bacterial control agent, isothiazolone compounds, particularly 5-chloro-2-methyl-4-isothiazolin-3-one has a wide antibacterial spectrum, is water-soluble and easy to handle, and It has been widely used because of its low toxicity (Japanese Patent Publication No. 58-4682 (Patent Document 1)).

  However, since 5-chloro-2-methyl-4-isothiazolin-3-one is unstable and has a high decomposition rate, there is a difficulty in sustaining the effect, and a long-term stable slime control that improves this point. 2-Methyl-4-isothiazolin-3-one has been proposed as an agent (Japanese Patent Laid-Open No. 2002-193712 (Patent Document 2)).

  According to this technique, although the improvement in the sustainability of the effect, which is a problem in the past, is markedly improved, 2-methyl-4-isothiazolin-3-one is a 5-chloro-2-methyl-4-isothiazoline. Since the sterilizing power itself is weaker than that of -3-one, there arises a problem that a large amount of a drug needs to be added to exert the effect.

Japanese Patent Publication No.58-4682 JP 2002-193712 A

  An object of the present invention is to provide a microbial control agent and a microbial control method having high microbial control performance even when added at a low concentration while maintaining the sustainability of the effect.

  The present invention solves such problems, that is, by using a specific cationic polymer in combination with 2-methyl-4-isothiazolin-3-one, a low concentration can be maintained while maintaining the durability of the effect. Even if it was added, it was found that a high bactericidal effect was exhibited, and the present invention was achieved.

  That is, the microorganism control agent of the present invention is poly [oxyethylene (dimethyliminio) ethylene (dimethyliminio) ethylene dichloride] and / or poly (2-hydroxypropyldimethylammonium chloride) as described in claim 1. ) And 2-methyl-4-isothiazolin-3-one as an active ingredient.

  In addition, the method for controlling microorganisms of the present invention comprises poly [oxyethylene (dimethyliminio) ethylene (dimethyliminio) ethylene dichloride] and / or poly (2-hydroxypropyldimethylammonium chloride) according to claim 2. ) And 2-methyl-4-isothiazolin-3-one as an active ingredient is added to aqueous water.

  The present invention relates to poly [oxyethylene (dimethyliminio) ethylene (dimethyliminio) ethylene dichloride] and / or poly (2-hydroxypropyldimethylammonium chloride) as 2-methyl-4-isothiazolin-3-one. Can be used to maintain excellent sterilization effects, and by combining them and adding them to the microbial control target water system, high sterilization can be achieved even at low concentrations while maintaining the sustainability of the effects. An effect can be obtained.

  In the present invention, poly [oxyethylene (dimethyliminio) ethylene (dimethyliminio) ethylene dichloride] and / or poly (2-hydroxypropyldimethylammonium chloride) and 2-methyl-4-isothiazolin-3-one Are preferably used in a weight ratio of 1: 100 to 100: 1 because a high effect can be obtained. A more preferred range is 1:10 to 10: 1. These drugs dissolve in water and are stable as a single agent.

  Poly [oxyethylene (dimethyliminio) ethylene (dimethyliminio) ethylene dichloride] and / or poly (2-hydroxypropyldimethylammonium chloride) and 2-methyl-4-isothiazolin-3-one are: It is preferable to add to the aqueous water for the purpose of controlling the microorganism so that the total concentration of the active ingredients is 2 mg / L or more and 1000 mg / L or less. If the addition concentration is less than 2 mg / L, a sufficient effect may not be obtained, and even if the addition concentration exceeds 1000 mg / L, an increase in the sterilization effect commensurate with the increase in the addition amount is difficult to obtain. The optimal addition range is 10 mg / L or more and 100 mg / L or less.

  In the microorganism control agent of the present invention, for the purpose of further improving the characteristics within the range where the effects of the present invention are not hindered, for example, acrylic acid-based, maleic acid-based, methacrylic acid-based, sulfonic acid-based, itaconic acid-based Or scale inhibitors such as isobutylene polymers, copolymers thereof, phosphoric acid polymers, phosphonic acid, phosphinic acid, or water-soluble salts thereof, such as 5-chloro-2-methyl-4 -Isothiazoline compounds other than 2-methyl-4-isothiazolin-3-one such as isothiazoline-3-one and 1,2-benzisothiazolin-3-one, aldehyde compounds such as glutaraldehyde and phthalaldehyde, hydrogen peroxide , Hydrazine, chlorine-based disinfectants (such as sodium hypochlorite), bromine-based and iodine-based disinfectants, and pyrithione compounds Products, dithiol compounds, thiocyanate compounds such as methylenebisthiocyanate, quaternary ammonium salt compounds, quaternary phosphonium salt compounds, pyridinium salt compounds, poly [oxyethylene (dimethyliminio) ethylene (dimethyliminio) ethylene Anti-slime agents such as cationic compounds such as ionene polymers other than dichloride and poly (2-hydroxypropyldimethylammonium chloride), azoles such as benzotriazole and tolyltriazole, and amine compounds such as ethylenediamine and diethylenetriamine Aminocarboxylic acid compounds such as nitrilotriacetic acid, ethylenediaminetetraacetic acid, diethylenetriaminepentaacetic acid, such as gluconic acid, citric acid, oxalic acid, formic acid, tartaric acid, phytin , Succinic acid, and organic carboxylic acids such as lactic acid, can be added to various water treatment agent, in which case is also included in the present invention.

<Example 1>
Cooling water collected from the cooling water system of a factory in Ibaraki Prefecture was used as test water.

  Take 30 mL of the test water in a 50 mL shake flask and concentrate the chemicals shown in Table 1 (also abbreviations are shown) in Table 2 (units in mg / L in the table. ”, And then cultured with shaking at 30 ° C. and 60 rpm. After 72 hours from the start of culture, the number of general bacteria in the test water was measured according to JIS K0101 63.2.

  The measurement results are also shown in Table 2 (“<10” in the table indicates less than 10 / mL). The general bacterial count of test water at the start of the test was 3500 cells / mL.

  According to Table 2, among various cationic polymers of A to E, a microorganism control agent comprising a combination of A or B which is a cationic polymer according to the present invention and 2-methyl-4-isothiazolin-3-one is another combination. It can be seen that it has an extremely high synergistic microbial control performance as compared with the use in a single agent or a single agent.

<Example 2>
Cooling water collected from the cooling water system for air conditioning in buildings in Tokyo was used as test water.

  Each 30 mL of the above test water was placed in a 50 mL shake flask, and the concentrations shown in Table 3 for the chemicals shown in Table 3 (abbreviations are also shown) (units in the table are mg / L. ”, And then cultured with shaking at 30 ° C. and 60 rpm. The number of general bacteria in the test water was measured according to JIS K0101 63.2, 24, 72 and 168 hours after the start of culture.

  The measurement results are also shown in Table 4 (“<10” in the table indicates less than 10 / mL). The number of general bacteria in the test water at the start of the test was 78000 / mL.

  Table 4 shows that the microbial control agent according to the present invention has a very high synergistic microbial control performance, and that the high microbial control performance is maintained for a long time. On the other hand, the combined use of 5-chloro-2-methyl-4-isothiazolin-3-one and a cationic polymer that have been widely used in the past has an immediate effect on the bactericidal effect and a synergistic effect is also recognized. No increase in the number of bacteria was observed after one week (168 hours).

Claims (2)

Poly [oxyethylene (dimethyliminio) ethylene (dimethyliminio) ethylene dichloride] and / or poly (2-hydroxypropyldimethylammonium chloride);
2-methyl-4-isothiazolin-3-one;
A microorganism control agent characterized by comprising as an active ingredient. Poly [oxyethylene (dimethyliminio) ethylene (dimethyliminio) ethylene dichloride] and / or poly (2-hydroxypropyldimethylammonium chloride);
2-methyl-4-isothiazolin-3-one;
A method for controlling microorganisms, which comprises adding as an active ingredient to aqueous water.