JPH05908A - Mildew proofing agent - Google Patents

Abstract

PURPOSE:To obtain a mildew proofing agent containing lactic acid, especially L-lactic acid obtained by fermentation method, capable of preventing the growth of mildew by attaching to the surface of a substrate, having high safety to human body and exhibiting excellent mildew proofing effect. CONSTITUTION:A mildew proofing agent containing L-lactic acid obtained fermentation method among lactic acid of D-lactic acid, L-lactic acid and D, L-lactic acid. Lactic acid, especially optically active L-lactic acid is usable also for infusion because of being metabolized in human body, having high biological safety and a low vapor pressure, and is free from malodor. When the mildew proofing agent is used, it is applied to an article to be targeted such as wall, apparatus or vessel all of which are liable to be grown with mildew. In a part where mildew has grown already, the mildew can be removed by washing off with sponge, etc., lightly after applying the agent. Similar effect is obtained also when L-lactic acid is mixed into other solvent and molded article. After removing mildew, when the agent is sometimes applied to an article to be targeted, mildew proofing effect is retained.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an antifungal agent. The antifungal agent of the present invention relates to a preparation for preventing and removing mold which frequently occurs in places with high humidity such as general households, public facilities, and industrial equipment.

[0002]

2. Description of the Related Art In recent years, with the completion of heating facilities and the airtightness of rooms, the occurrence of mold in rooms such as homes, offices and schools has been increasing. The appearance of mold is aesthetically
It is not good for hygiene. To prevent mold, it is necessary to keep it well-ventilated, dry and clean.
However, humid bathrooms and toilets, washrooms, or electronic devices such as refrigerators, ovens, mixers, tatami mats,
Molds easily occur on carpets and the like. In addition, various devices such as stirrers, kneaders, filling machines, underground cables, medical equipment, etc. will be moldy, causing damages such as dirt, unsanitary conditions, infection, and electric leakage. In addition, recently, a large number of psychrophilic molds that grow even under dry conditions have been reported, and there are very many cases of allergic symptoms caused by mold development.

Conventionally, a strong alkaline solution using hypochlorite and a strong acidic solution using hydrochloric acid are commercially available as commercially available agents for removing and preventing such molds.
All of these agents have a certain effect on mold removal, but they are very dangerous because they are strong alkali (pH 12 or more) or strong acid (pH 3 or less) .If they adhere to the skin, burns, peeling of skin, There is a risk of blindness. In addition, chlorine-based antifungal agents have a strong odor, cause inflammation of the nose and throat, and have a strong irritation to the eyes. Therefore, it is necessary to work with adequate ventilation. Moreover, chronic use of such an antifungal agent having a strong physicochemical action may cause a chronic respiratory disorder. An object of the present invention is to provide an antifungal agent which has an excellent antifungal effect and is not dangerous to the human body.

[0004]

The present invention provides a fungicide containing lactic acid. The fungicide of the present invention can prevent the generation of mold by adhering it to the surface of a substrate. Lactic acid used in the present invention is D-lactic acid, L
It may be either lactic acid or D, L-lactic acid. In particular, L-lactic acid obtained by the fermentation method is preferable because it is metabolized by the human body and is highly safe. The use of such lactic acid as a fungicide,
Preference is given to using lactic acid as an aqueous solution. The concentration of the aqueous lactic acid solution is 0.1 to 50%, preferably 1 to 10%.
%. If the concentration is lower than this range, sufficient antifungal effect cannot be obtained. Further, if the concentration is higher than this range, the price becomes high and the wastewater may be polluted. To prepare the aqueous lactic acid solution, it is preferable to add a predetermined amount of lactic acid powder to water and stir it. Alternatively, the 90% lactic acid fermentation liquid may be diluted with water. It is preferable to dissolve lactic acid at 1 to 30 ° C.

Lactic acid is an organic acid having a small dissociation constant next to acetic acid, and even if the pH is low, it does not affect the skin like conventional fungicides. In particular, L-lactic acid, which is an optically active substance, is a highly biosafe acid that is also used for infusion and is metabolized in the body, and has a low vapor pressure and no bad odor. The results of the fungicidal test of this fermented L-lactic acid are shown in Table 1.

(Test method) After 90% L-lactic acid was diluted to a predetermined concentration (50%, 10%), p was added with 1N-NaOH.
H-adjusted (pH 1, pH 3 and pH 7), Tables 1-3
Three L-lactic acid aqueous solutions each having a predetermined concentration shown in (3) were prepared, and 18 ml each was prepared in a test tube having an inner diameter of 26 mm. Pre-prepared test mold Penicillium funiculousum, Clado
A spore suspension (10 ⁵ to 10 ⁶ cells / ml) of spolium cladosporioides and Aureobacidium pullulams was placed in each test tube in an amount of 2 ml. This test tube was put in a constant temperature bath at 20 ° C., stirred occasionally, and 1.0 ml was taken out aseptically at 3 hours and 24 hours, and it was diluted with 0.005% aerosol OT sterilized water to 1 ml.
A 0-fold dilution series was made. Two stocks of peptone agar, 0.1 ml each from the stock solution of action and each dilution step, were spread with a Conradi stick. The medium was cultured at 27 ° C. for 7 days, and the number of mold colonies generated was counted. The results are shown in Tables 1-3.

(Test Results) Table 1 Fungicidal test for Peniciliun funiculousum ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ ━ Working time Samples Sample concentration 3 hours 24 hours ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ pH 1.0 50% (stock solution) <10 <10 10% <10 <10 ───────────────────────────────── ──── pH 3.0 50% (stock solution) <10 <10 10% <10 <10 ──────────────────────────── ───────── pH 7.0 50% (stock solution) 2.2 × 10^Five 3.6 x 10^Four  10% 4.5 x 10^Five 3.0 x 10^Five  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Sterilized distilled water 4.5 × 10^Five 3.8 x 10^Five  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

Table 2 Fungicidal test against Cladosporium cladosporioides ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Interval Sample concentration 3 hours 24 hours ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ pH 1.0 50 % (Stock solution) <10 <10 10% <10 <10 ───────────────────────────────────── pH 3.0 50% (stock solution) <10 <10 10% <10 <10 ──────────────────────────────── ───── pH 7.0 50% (stock solution) 2.0 × 10^Four 2.0 x 10^Four  10% 2.4 x 10^Four 2.3 x 10^Four  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Counter sterilized distilled water 2.1 × 10^Four 2.2 x 10^Four  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

Table 3 Fungicidal test against Aureobacidium pullulans ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Interval Sample concentration 3 hours 24 hours ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ pH 1.0 50 % (Stock solution) <10 <10 10% <10 <10 ───────────────────────────────────── pH 3.0 50% (stock solution) <10 <10 10% <10 <10 ──────────────────────────────── ───── pH 7.0 50% (stock solution) 2.7 × 10³ 1.2 × 10 10% 1.8 × 10^Five 1.2 x 10^Five  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Counter sterilized distilled water 3.0 × 10^Five 3.4 x 10^Five  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

As shown in Tables 1 to 3, even when the lactic acid concentration is 10% or less, the fungicidal property of L-lactic acid is remarkable at pH 3 or less. When L-lactic acid has a low dissociation constant and is used as a mildewproofing agent for households and businesses, it is preferable in terms of cost to lower the pH and use a low-concentration lactic acid solution. As described above, the optically active lactic acid, particularly L-lactic acid obtained by the fermentation method has a very high antibacterial and antifungal activity. This seems to be because undissociated lactic acid enters mold cells and destroys the metabolic system to kill mold, or lactic acid bacteria themselves produce substances having an antibacterial action.

The typical composition of the antifungal agent of the present invention is as follows:
L-lactic acid 1-10%, surfactant 0-5%, bleach 0-
An aqueous solution having a pH of 1 to 2 at 5% can be mentioned. Examples of the composition of the other fungicide include an aqueous solution of L-lactic acid 1 to 10% and alcohol 55% or less at a pH of 1 to 2.
This fungicide is mainly used in places where no mold is generated. The bactericidal action of alcohol is also added, and the fungicidal property of L-lactic acid is exhibited after the evaporation of alcohol.

These compositions are sprays, aerosols,
It is used by filling it in a container in a liquid form or the like. Before use, use a fungicide on walls, devices, or
Apply to objects such as appliances. Molds can be removed by lightly washing them with a sponge or the like after application on the part where mold has already occurred. Further, the same effect can be obtained by using L-lactic acid mixed with other solvents and molded articles. After removing the mold, it is sometimes applied to the object to maintain the antifungal effect.

In addition to lactic acid, an appropriate surface active agent such as a nonionic surface active agent and a bleaching agent such as H ₂ O ₂ may be added to the fungicide of the present invention.

[0014]

EXAMPLES Next, the present invention will be described more specifically based on examples. 5 parts by weight of L-lactic acid, ₂ parts by weight of H ₂ O ₂ , 3 parts by weight of a surfactant and 90 parts by weight of water were mixed to prepare an antifungal agent. The pH was 1.6. When this fungicide was applied to a bathroom image, no mold was found for about 3 months.

[0015]

EFFECT OF THE INVENTION The antifungal agent of the present invention is highly safe to the human body and has an excellent antifungal effect.

Claims (1)

[Claims] 1. An antifungal agent containing lactic acid.