JP2904824B2 - Industrial disinfectant and disinfection method - Google Patents

Description

The present invention relates to an industrial disinfectant and a disinfection method. More specifically, for the preservation and sterilization of papermaking process water in the paper and pulp industry, cooling water and washing water for various industries, heavy oil sludge, metalworking oils, fiber oils, paints, coating liquids for paper, latex and paste. The present invention relates to useful industrial germicides and sterilization methods.

(B) Conventional technology Conventional papermaking processes in the paper and pipe industries and cooling water systems in various industries have slimes caused by bacteria and fungi, and have obstacles such as reduced product quality and reduced production efficiency. It has been known. In addition, many industrial products such as heavy oil sludge, metalworking oils, fiber oils, paints, various latexes, sizing agents, and the like, cause decay and contamination by bacteria and fungi, thereby fouling the products and reducing their variety.

Many fungicides have been used to prevent damage by these microorganisms. In the past, organic mercury compounds and chlorinated phenol compounds were used, but these drugs are highly toxic to the human body and fish and shellfish, and their use is regulated because they cause environmental pollution. Low-toxic organic nitrogen sulfur compounds, organic halogen compounds and organic sulfur compounds are widely used as industrial germicides.

Isophthalonitrile derivatives, methylenebisthiocyanate and 2-bromo-2-nitro-1,3-diacetoxypropane, which are the active ingredients of the present invention, are each known as one of such relatively low-toxic fungicides. Things.

Although the above-mentioned various low-toxicity fungicides have low toxicity, it is desirable to reduce the amount of use as much as possible from the viewpoints of pollution, the environment, and the cost of sterilization treatment.

Accordingly, a fungicide that exhibits a bactericidal effect for a longer period of time with an addition amount as small as possible is inevitably desired. From this viewpoint, for example, 5-chloro-2,4,6-trifluoroisophthalonitrile, Studies have been conducted to develop a synergistic bactericidal effect in combination with an organic fungicide. And specifically, 5-chloro-2,4,6-trifluoroisophthalonitrile, 2-bromo-2-nitro-1,3-propanediol, 1,1-dibromo-1-nitro-2-yl A synergistic agent which is used in combination with a specific aliphatic nitro alcohol such as propanol has been proposed (JP-A-64-61402).
No.).

(C) Problems to be Solved by the Invention However, the above-mentioned conventional synergistic agent containing 5-chloro-2,4,6-trifluoroisophthalonitrile has a significantly reduced bactericidal efficacy due to a decrease in temperature. At the same time, there is a problem that the bactericidal effect is low in a neutral to alkaline aqueous system. Also, 5-chloro-2,4
-Difluoro-6-methoxyisophthalonitrile had a similar problem.

Therefore, for example, assuming a system to be sterilized such as papermaking process water in a paper / valve mill, even in the summer (for example, at a water temperature of 40 ° C.), even in an effective amount of addition in winter (for example, the water temperature).
At 17 ° C), the intended bactericidal effect cannot be obtained, and white water with a pH of 3.5 to 6 is targeted. White water with a pH of 7 to 8 is targeted even at an effective amount for so-called acidic papermaking process water. So-called neutral papermaking process water or alkaline papermaking process water has the disadvantage that the sterilizing effect is significantly reduced.

The present invention has been made under such circumstances, and in particular, 5-chloro-2,4,6-trifluoroisophthalonitrile which can exhibit excellent bactericidal efficacy even under a low temperature environment or under a neutral to alkaline environment. And / or 5-chloro-2,
It is intended to provide a new concomitant drug containing 4-difluoro-6-methoxyisophthalonitrile.

(D) Means for Solving the Problems Thus, according to the present invention, 5-chloro-2,4,6-trifluoroisophthalonitrile and 5-chloro-2,4
At least one isophthalonitrile derivative selected from -difluoro-6-methoxyisophthalonitrile;
There is provided an industrial bactericide comprising as an active ingredient at least one compound selected from methylene bisthiocyanate and 2-bromo-2-nitro-1,3-diacetoxypropane.

The isophthalonitrile derivative used in the present invention is
It is chloro-2,4,6-trifluoroisophthalonitrile or 5-chloro-2,4-difluoro-6-methoxyisophthalonitrile, which may be used as a mixture.
Among these, 5-chloro-2,4,6-trifluoroisophthalonitrile is preferred from the viewpoint of the bactericidal effect.

This invention relates to 5-chloro-2,4,6-trifluoroisophthalonitrile and 5-chloro-2,4-difluoro-6-
When methylenebisthiocyanate and / or 2-bromo-2-nitro-1,3-diacetoxypropane are selected from many organic fungicides as a drug to be used in combination with methoxyisophthalonitrile, a conventional concomitant drug is used. This is based on the discovery that a germicide having significantly improved germicidal efficacy in low-temperature and neutral papermaking process water can be obtained.

5-chloro-2,4,6 which is an essential component in the present invention
-Trifluoroisophthalonitrile [hereinafter referred to as compound (I)] or 5-chloro-2,4-difluoro-6-methoxyisophthalonitrile [hereinafter referred to as compound (II) is a known method, for example, Industrial magazines,
73 , 447 (1970) and JP-A-63-227502.

In the present invention, the compound (I) or (I
The methylene bisthiocyanate (hereinafter referred to as component (a)) and 2-bromo-2-nitro-1,3-diacetoxypropane (hereinafter referred to as component (b)) used in combination with I) are each, for example, JP-B-58-23847. No., JP-B-42-10386 and JP-A-56-
It is a bactericide described in 120603, and a commercial product can be applied as it is.

The bactericide of the present invention exerts an extremely excellent synergistic bactericidal action which cannot be expected from each active ingredient individually, and is broadly applicable to harmful microorganisms such as bacteria, fungi, and yeasts regardless of the type. Has coverage. Moreover, even if the temperature of the system to be sterilized is lowered, its excellent sterilizing effect does not decrease, and it exhibits excellent sterilizing action even at low temperatures, and in a neutral to alkaline environment such as a neutral papermaking process aqueous system. Also exerts an effective bactericidal effect.

In the fungicide of the present invention, compound (I) or (I
The mixing ratio of the component (a) and the component (a) and / or (b) is adjusted so that the synergistic bactericidal effect is efficiently exhibited, and from this viewpoint, the compound (I) or (II) and the component are used. The mixing ratio of (a) and / or (b) is from 1:10 to 1
A ratio of 0: 1 is suitable, and a ratio of 1: 5 to 5: 1 is preferable.

The fungicide of the present invention comprises the compound (I) or (II)
And component (a) and / or (b) can be prepared by homogeneously mixing the components as they are.
It is preferably used after being prepared in the form of a solvent solution, emulsified dispersion or the like.

Examples of solvents that can be used here include methanol, ethanol, alcohol solvents such as isopropanol, acetone, MEK, ketone solvents such as MIBK, dibutyl cellosolve, diethyl carbitol, methyl cellosolve, ethyl cellosolve, methyl carbitol, Ether solvents such as ethyl carbitol, methyl acetate, ethyl acetate, 3-methoxybutyl acetate, 2-
Examples thereof include ester solvents such as methoxyethyl acetate, 2-ethoxyethyl acetate and propylene carbonate, and hydrocarbon solvents such as xylene, diethylbenzene, naphtha and kerosene. Further, the bactericide of the present invention may be used by being supported on any carrier (for example, kaolin, clay, bentonite, CMC, etc.), and its form is not limited and various preparation forms can be adopted. Needless to say, stabilizers, surfactants and the like may be added as long as the effects of the present invention are not impaired.

The amount added when the fungicide of the present invention is used depends on the concentration of microorganisms in the system to be sterilized.
In the case of water systems in the field of the pulp industry, etc., the total concentration of the active ingredient is 0.01 to 100 ppm, and in the case of the fields of water-based paints, pastes, metalworking oils, etc., it is also 1 to 500 ppm, which is described above. An excellent bactericidal effect can be obtained.

However, the compound (I) or (II) and the components (a) and / or (b) used in the present invention may be added simultaneously or separately to the system to be sterilized, whereby The same bactericidal effect as described above can be obtained by the interaction of the components. Therefore, the present invention provides at least one of 5-chloro-2,4,6-trifluoroisophthalonitrile and 5-chloro-2,4-difluoro-6-methoxyisophthalonitrile for industrial sterilization. Sterilization by adding one isophthalonitrile derivative and at least one compound selected from methylenebisthiocyanate and 2-bromo-2-nitro-1,3-diacetoxypropane simultaneously or separately; The present invention also provides an industrial sterilization method characterized by the following.

(E) Example The industrial disinfectant of the present invention and the disinfectant of the comparative example were prepared according to the following formulation. All parts are by weight.

Example 1 5-chloro-2,4,6-trifluoroisophthalonitrile 10 parts Methylenebisthiocyanate 10 parts Propylene carbonate 80 parts Example 2 5-chloro-2,4,6-trifluoroisophthalonitrile 10 parts 2 -Bromo-2-nitro-1,3-diacetoxypropane 10 parts Propylene carbonate 80 parts Comparative example 1 5-chloro-2,4,6-trifluoroisophthalonitrile 20 parts Propylene carbonate 80 parts Comparative example 2 Methylene bisthiocyanate 20 parts Propylene carbonate 80 parts Comparative Example 3 2-bromo-2-nitro-1,3-diacetoxypropane 20 parts Propylene carbonate 80 parts Example 3 5-chloro-2,4-difluoro-6-methoxyisophthalonitrile 10 Part methylene bisthiocyanate 10 parts propylene carbonate 80 parts Example 4 5-chloro-2,4-difluoro-6 -Methoxyisophthalonitrile 10 parts 2-Bromo-2-nitro-1,3-diacetoxypropane 10 parts Propylene carbonate 80 parts Comparative Example 4 5-Chloro-2,4-difluoro-6-methoxyisophthalonitrile 20 parts Propylene 80 parts of carbonate (Evaluation of bactericidal effect) The bactericidal effects prepared in Examples 1 to 4 and Comparative Examples 1 to 4 were examined for bactericidal effects by the following test methods.

The above-mentioned preparation is adjusted to a predetermined concentration in white water [pH 7.6, Pseudomonas sp., Flavobacterium sp., Micrococcus sp., Bacillus sp.] Collected from a fine paper machine (neutral paper making) at a paper mill. After addition, 37 ° C, 27 ° C and 17 ° C
After shaking at 60 ° C for 60 minutes, the number of viable bacteria was measured.

The results are shown in Table 1. The drug concentration indicates the concentration of the used drug.

As is clear from the results in Table 1 above, according to the bactericide of the example, even though the amount of the active ingredient was the same, the bactericide superior to the bactericide of the comparative example (active ingredient alone). An effect has been achieved, and a synergistic effect is clearly observed. Further, it can be seen that not only an excellent synergistic effect is recognized, but also an excellent synergistic effect at a low temperature (17 ° C.) is equivalent to that at a high temperature (37 ° C.). Compound (I)
When comparing the cases of (II) and (II), the case of compound (I) is more preferred.

And, such a tendency is that the component (5 parts) is added to 1 part by weight of 5-chloro-2,4,6-trifluoroisophthalonitrile and / or 5-chloro-2,4-difluoro-6-methoxyisophthalonitrile. a) and / or (b)
It is particularly noticeable at a ratio of 0.2 to 5.

(F) Effects of the Invention According to the germicide and the germicidal method of the present invention, an excellent bactericidal effect is exhibited in various germicidal systems based on the synergistic action of each active ingredient. Therefore, it is possible to perform a sterilization treatment by using a lower concentration of the active ingredient than before.

Such an excellent sterilizing effect is hardly adversely affected even if the temperature or pH of the system to be sterilized changes.Especially even if the temperature of the papermaking process water fluctuates or the pH changes depending on the type of white water used. It does not decrease.

Therefore, the disinfectant and disinfecting method of the present invention are effective for disinfecting various target systems, especially in industrial water systems where temperature fluctuations occur as in papermaking process water or various liquid waters are applied. It is useful for the sterilization treatment.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI A01N 37:12) (72) Inventor Mamoru Yoshida 8 Ebisu-cho, Kanagawa-ku, Yokohama-shi, Kanagawa SDS Biotech Yokohama Plant (56) References JP-A-62-402 (JP, A) JP-A-63-264504 (JP, A) JP-A-64-61402 (JP, A) JP-A-3-118304 (JP, A) (58) Fields surveyed (Int.Cl. ⁶ , DB name) A01N 37/34 A01N 47/48 A01N 37/12 CA (STN)

Claims (7)

(57) [Claims] (1) 5-chloro-2,4,6-trifluoroisophthalonitrile and 5-chloro-2,4-difluoro-6
-Effectively at least one isophthalonitrile derivative selected from methoxyisophthalonitrile and at least one compound selected from methylenebisthiocyanate and 2-bromo-2-nitro-1,3-diacetoxypropane An industrial disinfectant characterized by containing as an ingredient. 2. The fungicide according to claim 1, wherein the isophthalonitrile derivative is 5-chloro-2,4,6-trifluoroisophthalonitrile. 3. The disinfectant according to claim 1, wherein the system to be disinfected is papermaking process water in a pulp and paper mill. 4. An industrial sterilization target system comprising 5-chloro-2,
At least one isophthalonitrile derivative selected from 4,6-trifluoroisophthalonitrile and 5-chloro-2,4-difluoro-6-methoxyisophthalonitrile, methylenebisthiocyanate and 2-bromo-2- An industrial sterilization method characterized by adding at least one compound selected from nitro-1,3-diacetoxypropane simultaneously or separately and sterilizing. 5. The method according to claim 4, wherein the isophthalonitrile derivative is 5-chloro-2,4,6-trifluoroisophthalonitrile. 6. The sterilization method according to claim 4, wherein the system to be sterilized is papermaking process water in a pulp and paper mill. 7. The sterilization method according to claim 6, wherein the papermaking process water has a pH of 7 to 8.