JPH08151307A - Industrial germicide and industrial germicidal method - Google Patents

Abstract

PURPOSE: To obtain an industrial germicide having marked effect on a broad spectrum of microorganisms at pH levels ranging from alkalinity to acidity, esp. in the alkaline region, consisting of a combination of 1,2-benzisothiazolin-3- one with methylenebisthiocyanate. CONSTITUTION: This industrial germicide having the above-mentioned effect contains a combination of 1,2-benzisothiazolin-3-one with methylenebisthiocyanate at the weight ratio of pref. (1:10) to (10:1). Disinfection with this germicide is conducted by adding either simultaneously or separately the above two kinds of compounds to the object system to be disinfected so as to come to 0.5-200mg/l in the concentration of the active ingredient. This germicide has marked effect through the synergistic effect of the two kinds of compounds, being effective for a long period at low concentrations.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to industrial fungicides. More specifically, it relates to an industrial sterilizer and an industrial sterilization method, which are useful for sterilization of a system to be sterilized in an alkaline to neutral to acidic range, particularly an alkaline range.

[0002]

2. Description of the Related Art Conventional water for papermaking process in the paper and pulp industry, cooling water for various industries, washing water, metalworking oil, fiber oil, paint, antifouling paint, paper coating It is known that sterilization target systems such as working fluids, latex, sizing agents, starch slurries, coating colors, etc. cause spoilage and contamination due to bacteria and fungi, and have problems such as deterioration of product quality and production efficiency. ing.

Among the above-mentioned sterilization target systems, especially latex,
With resin emulsions, rosin emulsions, coating colors, calcium carbonate slurries, cutting oils, metalworking oils, etc., there is a tendency that the number of cases in which the property becomes alkaline with a pH of 7 or higher due to changes or improvements in raw materials. For example, carboxylate-modified latex has been manufactured to improve stability, but the pH of this latex is alkaline, and the coating color using this latex and the coating using calcium carbonate as the pigment of the coating color The color liquid becomes alkaline with a pH of 7 or higher.

Alkali-swelling latex is used for gravure printing, and the liquidity of the alkali-swelling latex is also alkaline with pH of 7 or more. If the cutting oil is an emulsion type, it contains mineral oil and a surfactant and is used in the state of an emulsion after being diluted with water at the cutting site, but the cutting oil contains alkanolamine, inorganic alkali, etc. for rust prevention purposes. It is compounded and its liquidity becomes alkaline with pH of 7 or more.

Therefore, in order to prevent damages caused by various microorganisms in the alkaline region, a bactericidal agent which exerts an excellent bactericidal effect at a low concentration in the alkaline region as well as in the acidic to neutral regions, and which lasts for a long time, is desired. Has been done. Usually, a bactericide is used with low toxicity from the viewpoint of pollution and environmental protection, but a single bactericide is effective only for a narrow range of microorganisms in the sterilization target system, and therefore a target system in which various microorganisms are mixed In addition, there is a problem that sufficient bactericidal effect cannot be obtained, and there is a problem that resistant microorganisms appear even when effective microorganisms are used for a long time.

Therefore, it is customary to use a bactericide in combination for the purpose of exerting a synergistic effect. However, many bactericides composed of combinations of these low-toxicity bactericides are stable in the acidic range and decompose in the alkaline range, so long-term effects cannot be expected. For example, JP-A-5-16
No. 3107 discloses a composition of an isothiazolone compound or a magnesium complex salt thereof and methylenebisthiocyanate. However, this composition is described to exhibit a bactericidal action against microorganisms in the acidic to neutral range, but there is no description of the effect on the microorganisms in the alkaline range.

When a metal complex salt of an isothiazolone compound such as a magnesium salt of an isothiazolone compound is added to a polymer emulsion such as latex, the emulsion phase is destroyed and phase separation or coagulation occurs. So-called emulsion shock occurs, making it difficult to use.

[0008]

From this point of view, the inventor of the present invention has studied the combination and content ratio of various industrial bactericides, and as a result, 1,2-benzisothiazolin-3-one and methylenebisthiocyanate have been studied. It has been found that, by using in combination with, the remarkable bactericidal effect against a wide variety of microorganisms and the sustainability of the bactericidal effect are exhibited in the alkaline to neutral to acidic regions, particularly in the alkaline region.

Thus, according to the present invention, there is provided an industrial fungicide containing 1,2-benzisothiazolin-3-one (A) and methylenebisthiocyanate (B) as active ingredients. . Although details of the reason why such a remarkable effect is exerted are not clear, it is considered to be a synergistic effect due to a combination of specific compounds in specific ratios.

The 1,2-benzisothiazolin-3-one (A) and methylenebisthiocyanate used in the present invention are known compounds, and commercially available products are used.
In the present invention, the mixing ratio of the component (A) and the component (B) is preferably 1:10 to 10: 1 (weight ratio), and more preferably 3: 7 to 7: 3. It is preferable because the effect is exhibited.

The active ingredient of the present invention is usually preferably used in the form of a liquid preparation. However, the present invention is not limited to this, and may be used in the form of powder or the like depending on the object of use. The liquid preparation is prepared by dissolving the active ingredient in a hydrophilic organic solvent and adding a dispersant if necessary.

Examples of the hydrophilic organic solvent include amides such as dimethylformamide, glycols such as ethylene glycol, propylene glycol, diethylene glycol and dipropylene glycol, methyl cellosolve, phenyl cellosolve, diethylene glycol monomethyl ether and dipropylene glycol monomethyl ether. , Glycol ethers such as tripropylene glycol monomethyl ether, alcohols having up to 8 carbon atoms, methyl acetate, ethyl acetate, 3-methoxybutyl acetate, 2-ethoxymethyl acetate, 2-ethoxyethyl acetate, propylene carbonate, dimethyl glutarate. And the like.

Among these hydrophilic solvents, glycol ethers such as methyl cellosolve, phenyl cellosolve, diethylene glycol monomethyl ether, dipropylene glycol monomethyl ether, and tripropylene glycol monomethyl ether, having up to 8 carbon atoms, from the viewpoint of safety and stability. Alcohols or methyl acetate, ethyl acetate, 3-methoxybutyl acetate, 2-
Esters such as ethoxymethyl acetate, 2-ethoxyethyl acetate, propylene carbonate and dimethyl glutarate are preferred.

As the dispersant, a cationic surfactant,
Anionic surfactants, nonionic surfactants or amphoteric surfactants are suitable, and nonionic surfactants are preferred from the viewpoint of stability as a preparation. Examples of the nonionic surfactant include higher alcohol-ethylene oxide (EO) adducts, alkylphenol E.I. O adduct,
Fatty acid E. O adduct, polyhydric alcohol fatty acid ester E. O adduct, alkylamine E.I. O adduct, fatty acid amide E. O adducts, E. O adduct, propylene oxide (PO) / E. O copolymer, alkylamine P.O. OE O-copolymer adduct, fatty acid ester of glycerin, fatty acid ester of pentaerythritol, fatty acid ester of sorbitol and sorbitan, fatty acid ester of sucrose, alkyl ether of polyhydric alcohol,
Examples include alkylolamide. Of these, higher alcohol E. O adduct, alkylphenol E.I. O adduct, polyhydric alcohol fatty acid ester E. O adduct, fatty acid amide E. O adducts, P. OE O copolymer, alkyl ether of polyhydric alcohol, alkylamine P.O. O
-E. O-copolymer adducts and achirolamides or combinations of two or more thereof are preferred, and alkylamine P.I. OE O copolymer adduct (for example, N, N,
The use of nonionic surfactants of N ', N'-polyoxypropylene, polyoxyethylenediamine, etc.) or alkylolamide type is particularly preferred. In some cases (for example, when the stability of the preparation does not matter), a cationic, anionic or amphoteric surfactant may be used.

The blending ratio of these preparations is such that the total amount of the active ingredients is 1 to 50 parts by weight, the dispersant is at least 0.01 parts by weight with respect to 1 part by weight of the total active ingredients, and the balance is the hydrophilic organic solvent. Is preferred. This liquid agent includes various water systems such as process water for papermaking process, industrial cooling water, starch slurry, synthetic resin emulsion, latex, etc.
It is applied in the case of coating color.

Further, for the system to be sterilized in which the active ingredient of the present invention can be directly dissolved or dispersed, it may be a powder formulation directly or diluted with a solid diluent (for example, kaolin, clay, bentonite, CMC, etc.). Alternatively, the above surfactants may be used. Further, when the system to be sterilized is an oil system such as cutting oil or oil paint, it is preferable to use kerosene, heavy oil, a liquid agent using a hydrocarbon solvent such as spindle oil,
You may use the said surfactant.

Although the amount of the composition of the present invention added varies depending on the object to be sterilized, it is usually 0.5 to 2 as the concentration of the active ingredient.
About 00 mg / 1 is sufficient. From this point of view, there is provided an industrial sterilization method characterized by adding the above-mentioned active ingredients to the system for industrial sterilization simultaneously or separately. In the method of the present invention, when the above-mentioned active ingredients are added simultaneously, it is convenient to use the same preparation as described above, but the same effect is exhibited even if they are added separately. Also in this case, the above-mentioned formulation form is preferable.

[0018]

EXAMPLES The present invention will be illustrated by formulation examples, test examples and comparative examples. Formulation Example (Preparation Method) 1,2-benzisothiazolin-3-one, methylenebisthiocyanate, and hydrophilic organic solvent, which are the active ingredients of the present invention, were added at the compounding ratio (% by weight) shown in Table 1, and the mixture was stirred at room temperature Stir and mix.

[0019]

[Table 1]

BIT: 1,2-benzisothiazolin-3-one MBTC: methylenebisthiocyanate MDG: diethylene glycol monomethyl ether DMF: N, N-dimethylformamide PC: propylene carbonate

Test Example 1 [Continuous Efficacy Confirmation Test Against Standard Bacteria] (Evaluation Method) Usually, the synergistic action between two components is measured by a binary dilution method. Both components are diluted to a predetermined concentration and added to the medium in fixed amounts. After inoculating this with a microorganism and culturing under a certain condition, the concentration at which no growth of the microorganism is observed is defined as the minimum inhibitory concentration by the binary dilution method. FIG. 3 is a graph in which the minimum inhibitory concentration of each component is made equal on both axes using normal scale coordinates. The area above the curve of this graph, ie, the TDMIC curve, represents the growth inhibition zone, and the area below the curve represents the proliferation zone. Also, if there is a curve above the diagonal line, an antagonistic action is shown, and if it is below the diagonal line, a synergistic action is shown. (Measurement method) Bacill pre-cultured in broth medium
10 times diluted pH 7.0 and pH 9.0 of us subtilis
To the broth medium adjusted to the above so that the viable cell count becomes 10 ⁶ cells / ml or more, and each drug is added to the broth medium at 37 ° C.
Shaked for days. The minimum inhibitory concentration (MIC) at that time is shown in FIGS. 1 and 2.

Test Example 2 [Synergistic effect on latex] A drug was added to SBR latex (pH 8.9) so as to have each concentration, and the mixture was allowed to stand in a constant temperature bath at 30 ° C. On the 3rd, 5th and 7th days, the bacterial count was measured daily while adding 1% of the drug-free latex. The results are shown in Table 2.

[0023]

[Table 2]

Test Example 3 [Synergistic effect on coating color] Rotting coating color (pH 7.
5) was sampled, a drug was added to each concentration so as to be left in a thermostat bath at 30 ° C., and the number of bacteria was measured daily. Table 3 shows the results.

[0025]

[Table 3]

(Consideration of Test Example) From the test results, BIT and MB which are the active ingredients of the present invention in the alkaline range.
TC shows a remarkable synergistic effect, and it can be seen that the bactericidal effect is exerted for a long period of time at a lower concentration than when used alone. In particular, in Test Example 2, a strong bactericidal effect was obtained even though the inoculum was further added on the third, fifth, and seventh day after the start of the test to make the condition severe.

[0027]

INDUSTRIAL APPLICABILITY The industrial bactericidal agent of the present invention exhibits an excellent synergistic bactericidal action in a system to be sterilized in an alkaline to neutral to acidic range, particularly in an alkaline range, and is effective at a low concentration for a long period of time.

[Brief description of drawings]

FIG. 1 is a MIC graph showing the synergistic effect of the active ingredient of the present invention in a pH 7.0 medium.

FIG. 2 is a MIC graph showing the synergistic effect of the active ingredient of the present invention in a medium of pH 9.0.

FIG. 3 is a MIC graph diagram for determining a synergistic effect applied in the present invention.

Claims (3)

[Claims] 1. An industrial germicide comprising 1,2-benzisothiazolin-3-one (A) and methylenebisthiocyanate (B) as active ingredients. 2. The industrial bactericide according to claim 1, wherein the compounding ratio of the compound (A) and the compound (B) is 1:10 to 10: 1 (weight ratio). 3. A system to be sterilized containing 1,2-benzisothiazolin-3-one (A) and methylenebisthiocyanate (B) in a ratio of (A) to (B) of 1:10 to 10: 1. The composition blended in the above is used as an active ingredient concentration of 0.5 to
An industrial sterilization method, characterized in that sterilization is performed by simultaneously or separately adding 200 mg / l so as to achieve sterilization.