JPH05201809A - Microorganism controlling agent - Google Patents

Abstract

(57) [Summary] [Purpose] An object of the present invention is to provide a microbial control agent having long-term storage stability and improved stability that can withstand a long use period. [Structure] A microbial control agent containing one or more isothiazolone compounds represented by the following general formula, 2-bromo-2-nitropropane-1,3-diol, and gluconic acid or a salt thereof. .. [Chemical 3] (In the formula, R represents a hydrogen atom, an alkyl group, a lower alkenyl group, a lower alkynyl group or a benzyl group, X and X'represent a hydrogen atom or a halogen atom, and M represents an ammonium, an alkaline earth metal or a heavy metal. Represents a cation,
Z represents an anion forming a compound with M having sufficient solubility in water, a represents an integer of 1 or 2, and n
Represents an integer in which Z satisfies the valence of M. )

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a microbial control agent having improved storage stability. More specifically, the safety for preventing the formation of slime by preventing the generation of bacteria and algae in the circulating water system such as the heat exchange water system in the industrial product production process or the temperature control equipment such as buildings. Microbial control agent.

[0002]

2. Description of the Related Art Conventionally, water for paper making processes, metal working oil circulation processes, industrial cooling water circulation processes, etc. in paper pulp mills, and industrial water-containing products such as water-based paints, paper coating solutions, printing pastes, etc. It is known that microorganisms such as bacteria, filamentous fungi, yeasts and algae easily propagate and cause various disorders. In particular, it is known that in a water system that is circulated and used, when mud or slime is generated, the flow in a pipe is hindered and cooling efficiency is reduced, leading to economic loss.

Therefore, organometallic compounds containing heavy metals such as mercury and tin have been conventionally used as agents for controlling these harmful microorganisms, but they are highly toxic and not preferable from the viewpoint of environmental protection. Therefore, there is a demand for a microbial generation inhibitor that has low toxicity and can be handled safely, and that is less likely to cause pollution even when discharged to the environment, and various pharmaceutical compositions have been proposed.

Among them, 2-bromo-2-nitropropane- is used as an antibacterial / algae agent which is less likely to cause environmental pollution.
A composition containing 1,3-diol (general name bronopol) and an isothiazolone compound as active ingredients has been proposed (see, for example, JP-B-58-4682). This composition has a synergistic effect in terms of the inhibitory effect on microbial generation and slime formation and the stability of the preparation, as compared with the case where bronopol or an isothiazolone compound is used alone, and isothiazolone is used in the form of a complex compound. Therefore, it is stable for a longer period of time than using isothiazolone which is not a complex compound, and is an excellent microbial control agent,
It is described to be a slime formation inhibitor.

[0005]

However, the antibacterial and algae agents of the above-mentioned technology are not always sufficient in storage stability, and if they are stored for a long period of time, they are decomposed, and as the isothiazolone complex compound is decomposed, precipitates are formed. Come on. At the same time, the decomposition of bronopol is promoted, resulting in a decrease in the activity against microorganisms. Therefore, the present invention has an object to provide a microbial control agent having long-term storage stability and improved stability that can withstand a long use period.

[0006]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present inventor has found that the stability of the composition can be remarkably improved by further blending a specific compound. And have completed the present invention. That is, the present invention is a microorganism containing one or more isothiazolone compounds represented by the following general formula, 2-bromo-2-nitropropane-1,3-diol, and gluconic acid or a salt thereof. It is a control agent.

[0007]

[Chemical 2] (In the formula, R represents a hydrogen atom, an alkyl group, a lower alkenyl group, a lower alkynyl group or a benzyl group, X and X'represent a hydrogen atom or a halogen atom, and M represents an ammonium, an alkaline earth metal or a heavy metal. Represents a cation,
Z represents an anion forming a compound with M having sufficient solubility in water, a represents an integer of 1 or 2, and n
Represents an integer in which Z satisfies the valence of M. )

The isothiazolone compounds used in the microbial control agent of the present invention include, for example, 2-methyl-3-isothiazolone, 2-ethyl-3-isothiazolone, 2-octyl-4-chloro-isothiazolone, 2-benzyl-4, 5
-Dichloro-3-isothiazolone, 2-allyl-3-isothiazolone, 2-propynyl-3-isothiazolone,
It is a complex compound such as 5-chloro-2-methyl-3-isothiazolone, for example, zinc chloride, copper chloride, copper nitrate, calcium chloride, magnesium chloride, magnesium nitrate and the like. A particularly preferred example is 5-chloro-2-methyl-3-isothiazolone calcium chloride, or
-Methyl-3-isothiazolone, a mixture with calcium chloride, a mixture of 5-chloro-2-methyl-4-isothiazolin-3-one magnesium chloride and 2-methyl-4-isothiazolin-3-one magnesium chloride, and the like. be able to.

The 2-bromo-2-nitropropane-1,3-diol used in the microbial control agent of the present invention is industrially provided under the general name bronopol. Further, among the gluconic acid or salts thereof used in the microbial control agent of the present invention, the salt of gluconic acid is a normal salt such as potassium, sodium or ammonium salt of gluconic acid.

The mixing ratio of the isothiazolone compound used for the microbial control agent of the present invention and bronopol is 0.1 parts by weight of bronopol to 1 part by weight of the isothiazolone compound.
10 to 10 parts by weight, and preferably 1 to 5 parts by weight from the viewpoint of microbial control effect and stability. The amount of gluconic acid or its salt to be added is 0.1 to 10 parts by weight per 1 part by weight of the mixture of the active ingredient of the microbial control agent, that is, the isothiazolone compound and bronopol.

The content of the active ingredient, that is, the isothiazolone compound or bronopol in the preparation is preferably 20% by weight or less. 20% by weight of each of these
When it exceeds, the stability of the isothiazolone compound is extremely deteriorated, and decomposition and precipitation easily occur, and bronopol may be crystallized during low temperature storage and precipitated in the preparation. On the contrary, if the concentration of the isothiazolone compound and bronopol in the formulation is too low, the amount of chemicals added to the water will be too large to be practical, so the total amount of active ingredients in the formulation may be 1% by weight or more. desirable. The concentration of gluconic acid or its salt is also preferably 1% by weight or more.

The microbial control agent of the present invention is preferably used by formulating it in an emulsion or a wettable powder. However, it is also possible to formulate each of the mixed components individually and mix them at the time of use.

[0013]

The microbial control agent of the present invention has long-term storage stability and improved stability capable of withstanding long-term use, and a low addition amount to water is sufficient. Has a microbial control effect.

[0014]

EXAMPLES The present invention will be described below with reference to examples, but% in the examples is by weight. After the chemicals formulated as shown in Table 1 were allowed to stand at 55 ° C. for 2 months, the presence or absence of precipitates was observed. When the precipitate was examined by fluorescent X-ray and X-ray diffraction, it was found to be sulfur. In addition,
The compounding ingredient used, "Caisson WT," is 5-chloro-2.
15% aqueous solution of isothiazolone compound consisting of a 3: 1 mixture of -methyl-4-isothiazolin-3-one magnesium chloride and 2-methyl-4-isothiazolin-3-one magnesium chloride.

Further, the content of bronopol in the preparation after being left for 2 months was measured by high performance liquid chromatography (HPLC) under the following analytical conditions to measure the decomposition rate of bronopol. Column: Tosoh Corporation, TSKgel ODS-80
TM 4.6mm ID x 25cm Guard column: same, TSK guardgel ODS-80TM
3.2mm ID x 1.5cm Eluent: 5% acetonitrile Flow rate: 1.0ml / min Sample volume: 20μl Detector: UV meter (215nm)

Further, the change in the algicidal effect before and after leaving for 2 months was examined as follows, and the results are also shown in Table 1. Pre-cultured Chlorella sp. Was suspended in Detomer medium diluted to 1/2 so that the dry weight was 0.2 mg per ml, and 15 ml was dispensed into each L-shaped test tube for evaluation. The concentration of the drug to be added is 30 to 10
After adding 5 mg / l in increments of 0 mg / l, add 100
Irradiate with 00lx of light and shake at 30rpm, 30 ℃
Culture was carried out for 7 days. After 7 days, the color tone of Chlorella sp. Was observed, and the minimum concentration at which the green color disappeared to give a pale yellowish white color was determined and used as the algicidal activity. The algicidal activity (minimum algicidal concentration) of each drug thus obtained is also shown in Table 1.

[0017]

[Table 1] Table 1 ────────────────────────────── Sample No. 1 ^* 2 3 ───────── ────────────────────── Caisson WT 20% 20% 20% Bronopol 5 5 5 Gluconic Acid-5-combined Sodium Gluconate-5 Pure Water 75 70 70 ────────────────────────────── Minimum algicidal concentration (initial) 50mg / l 50mg / l 50mg / l 〃 ( After 2 months) 75 mg / l 50 mg / l 55 mg / l Presence or absence of precipitate Yes No No Bronopol decomposition rate 20% 3% 5% ─────────────────────── ───────── *: Comparative example

[0018]

EFFECTS OF THE INVENTION The microbial control agent of the present invention exhibits a sufficient antibacterial and algae effect even when used at a low concentration in water and can be used as an advantageous drug in terms of safety, and is also active for long-term storage. It is possible to effectively suppress the generation of slime without damaging the above.

Claims (1)

[Claims] 1. A microorganism containing one or more isothiazolone compounds represented by the following general formula, 2-bromo-2-nitropropane-1,3-diol, and gluconic acid or a salt thereof. Control agent. [Chemical 1] (In the formula, R represents a hydrogen atom, an alkyl group, a lower alkenyl group, a lower alkynyl group or a benzyl group, X and X'represent a hydrogen atom or a halogen atom, and M represents an ammonium, an alkaline earth metal or a heavy metal. Represents a cation,
Z represents an anion forming a compound with M having sufficient solubility in water, a represents an integer of 1 or 2, and n
Represents an integer in which Z satisfies the valence of M. )