JPH01197412A - Antimicrobial agent - Google Patents

Abstract

PURPOSE:To obtain an antimicrobial agent suitable for the treatment of industrial water relating to paper and pulp industries and of cooling water for various industries, by using a halogenated acetic acid ester and 4,5-dichloro-2- octylisothiazolin-3-one as active components. CONSTITUTION:The objective agent contains (A) a compound of formula I (X is halogen; R is alkylene or alkenylene) having extremely poor activity against bacteria and yeasts and giving no required effect against molds at a low concentration, e.g., 2-bis-(bromoacetoxy)ethane and (B) the compound of formula II giving no required effect against yeasts, bacteria and molds at a low concentration. The ratio of A:B is 1:100-100:1, preferably 1:50-50:1. The concentration of the antimicrobial agent in the treating object is 0.01-100ppm in the field of paper and pulp industries and 1-500ppm in the field of water-base paint, paste, etc.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a halogenated acetate represented by the general formula (1) and a 4,5-dichloro-2
-Octylisothiazolin-3-one (hereinafter referred to as rDOIT)
Sometimes abbreviated as J. ) and a novel antibacterial agent that utilizes the synergistic effect of both.

This antibacterial agent is suitably used in industrial water systems related to the paper pulp industry and cooling water for various industries.

(Prior art and problems) Conventionally, wastewater from the papermaking process in the Gion Valp industry field,
It is harmful to various water systems such as circulating cooling water in various industrial fields, as well as water-based paints, paper coating fluids, latex, printing pastes, leather, etc. that are made using industrial water. microorganisms are likely to multiply, which causes a decline in productivity and quality.

In particular, slime has recently been generated in water systems in the Gion pulp industry due to the proliferation of filamentous fungi and yeasts, and slime has been generated in waterways where pulp slurry flows, especially in areas with rough walls that come in contact with slurry, chests, flow boxes, transport pipes, etc. In other places where the flow rate of the pulp slurry is low and stagnates, slime is formed. This slime often detaches, causing paper scraps and contamination of Gi pulp products, as well as causing various problems due to the growth of microorganisms.

The occurrence of such failures becomes a particularly serious problem when high-speed machines are used, resulting in a significant decrease in productivity and economic loss.

Furthermore, in the circulating water system for cooling metal processing fluids, microorganisms multiply and multiply, impairing the cooling performance and emulsifying properties of processing fluids, and producing bad odors, deteriorating the working environment, which is an undesirable phenomenon in terms of public health. is causing the

In addition, in a cooling water system, when microorganisms multiply and slime is generated, it causes a decrease in heat transfer efficiency of a heat exchanger and blockage of flow paths.

Other problems caused by the growth of harmful microorganisms occur in industrial products such as water-based paints, paper coatings, polymer latexes, paper pulp, glues, leather, and metalworking fluids.

By the way, the agents for suppressing or controlling the occurrence of harmful microorganisms in the water system or the industrial products include:
Until now, for example, organometallic compounds, organochlorine compounds,
Organic sulfur compounds, quaternary ammonium salt compounds, etc. have been used, but these compounds are toxic to the human body, emit bad odors and strange odors, and even cause undesirable phenomena such as firing. arise. In addition, when water systems containing these pesticides are dumped into rivers, oceans, etc., they have an adverse effect on fish and shellfish, causing problems in terms of environmental conservation.

(Object, structure, and effect of the invention) The present inventors have completed the present invention as a result of extensive research in order to eliminate the above-mentioned drawbacks of antibacterial agents.

That is, the present invention is as follows.

A halogenated acetate ester represented by the following general formula (wherein, (1:100) ~ (100:1)
An antibacterial agent characterized by containing in a weight ratio of

The activity is significantly inferior, and the desired effect cannot be obtained even at low concentrations against filamentous fungi.

Furthermore, the same (4,5-dichloro-2-octyls, bacteria, and filamentous fungi) cannot achieve the desired effect at low concentrations.

The antibacterial agent of the present invention has a wide range of applicability against harmful microorganisms such as filamentous fungi, bacteria, yeast, etc., irrespective of the type, which is far beyond what could be expected from the constituent components alone.

Hereinafter, the antibacterial agent of the present invention will be explained in detail.

As the compound of general formula (1) in the present invention, the following can be exemplified.

Compound (1) BrCHzCOCHzCHzOCCllzBr compound (
2) BrCIIzCOC1lCHzOCCHzBrCH30 Compound (3) Compound (4) The above-described halogenated acetate ester has a specific weight ratio of (1:100) to (100:1), preferably (1:1).
50) to (50:1).

If either one is too small, a satisfactory effect cannot be achieved.

The antibacterial agent of the present invention is basically produced by uniformly mixing the above two components.

- For boat fishing, it can be used as an aqueous solution, solvent solution, emulsified dispersion, etc.

Examples of solvents that can be used here include alcohol solvents, ketone solvents, ether solvents, and hydrocarbon solvents. Further, the industrial disinfectant of the present invention may be used by being supported on any carrier, and there are no particular restrictions on the mode of use, and various methods can be adopted.

The amount added when using antibacterial agents varies depending on the microbial concentration, but - 0.01 to 1100 pp for water systems in fields such as boat fishing and paper and pulp industry, water-based paints, glues, etc.
In the case of fields such as leather, it is 1 to 500 ppm, and a good bactericidal effect can be obtained at this level.

There is no problem in adding stabilizers, surfactants, etc. to the antibacterial agent of the present invention as long as they do not impede the purpose of the present invention.

(Examples and Comparative Examples) Antibacterial agents were manufactured using the following formulation. All parts in the examples indicate parts by weight.

Example 1 1.2-bis-(bromoacetoxy) 25 parts Ethane DOIT 5 parts Diethylene glycol monomethyl 68 parts Ether (solvent) Rapizole B-80 (surfactant, 2 parts manufactured by NOF Corporation) Example 2 1.4- Bis-(bromoacetoxy) 25 parts Butene DOIT 5 parts Diethylene glycol monomethyl 68 parts Etherrapizole B-802 parts Comparative Example 1 ■,2-Bis-(bromoacetoxy) 30 parts Ethane diethylene glycol monomethyl 68 parts Etherrapizole B-802 parts Comparative example 2 1.4-bis-(bromoacetoxy) 30 parts Butene diethylene glycol monomethyl 68 parts Ether Lapisol B-80 2 parts Comparative example 3 DOIT 30 parts Diethylene glycol monomethyl 68 parts Ether Lapisol B-80 2 parts (Efficacy test) Above examples Regarding the antibacterial agents produced in Comparative Examples 1 to 2 and Comparative Examples 1 to 3, the microbial growth inhibitory concentration, slime generation prevention effect, and antibacterial effect were investigated using the following test methods (hereinafter,
% indicates weight %. ).

Test Example 1 [Microbial Growth Inhibitory Concentration Test] The composition of the medium used was a mixed aqueous solution of 0.1% peptone, 0.05% glucose, 0.01% potassium phosphate, and 0.005% magnesium sulfate. The test method is to suspend the following test bacteria in a prepared culture solution, take a certain amount of this into a clean test tube,
Antibacterial agents at specified concentrations of 5, 10, 120, 40, and 80 ppm were added thereto, and cultured with shaking at 32°C.

The degree of growth of the microorganisms was determined based on the turbidity produced by the proliferation of the bacteria after 24 hours. The concentration that completely inhibits the growth of the microorganisms was determined by observing when no microorganism growth was observed.

The results are shown in Table 1.

The bacterial name abbreviations of the test bacteria are as follows.

Test bacteria Pse: Pseudomonas aerugi
nosaA,a: Aerobacter aer
ogenesB,s: Bacillus 5u
btillisA,v: 8lcaligene
s viscosesA,n: 8spe
rgillus nigerG, sp: Geot
richum sp.

Table 1 (Note 1) Values indicate the minimum concentration (ppm) that completely inhibits growth.

(Note 2) + indicates complete growth of the test bacteria.

As is clear from Table 1 above, the antibacterial agents of the present invention (Examples 1 and 2) are effective against all test bacteria at low concentrations of topp... It can be seen that it is not possible to obtain a uniformly effective effect on all test bacteria.

Test Example 2 [Test to prevent bacterial growth and slime generation in wastewater after papermaking process] The antibacterial agents produced in Examples 1 to 2 and Comparative Examples 1 to 3 above were applied to white water bits for 1 day in the papermaking process of a certain papermaking factory. The solution was added three times for 2 hours for 7 days so that the water concentration was 20 ppm, and the number of microorganisms in the white water was measured.

The test method involved diluting a white water sample with sterilized water, taking a quantitative amount of this in a Petri dish, and pouring dissolved Waxman agar medium into it, mixing it, and solidifying it into a flat plate.

After culturing in a thermostatic chamber (32°C) for 2 days, the microbial colonies generated were measured using a colony counter. The number of paper breaks during papermaking was also measured to confirm the bactericidal effect.

Table 2 From the results in Table 2 above, the antibacterial agent of the present invention (Examples 1 to 2)
) was found to have an excellent effect of inhibiting bacterial growth.

Test Example 3 [Bacterial growth prevention test in papermaking coating fluid] pH
A bouillon liquid medium and a previously spoiled coating solution were added to a 10.0 starch-based coating solution, stirred, and 300 ppm? 74
The antibacterial agent prepared above was added to the solution.

After storing this in a thermostat at 32° C. for 5 days, the number of viable bacteria in each coating solution was measured. The results are shown in Table 3 below.

Table 3

Claims (1)

[Claims] Halogenated acetic acid represented by the following general formula ▲ Numerical formulas, chemical formulas, tables, etc.▼... (I) (wherein, X represents a halogen, and R represents an alkylene group or an alkenylene group) Ester and 4,5-dichloro-2-octylisothiazolin-3-one represented by the following formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼... (II) (1:100) to (100:1)
An antibacterial agent characterized by containing in a weight ratio of