JPH0329761B2 - - Google Patents

Description

[Detailed description of the invention]

TECHNICAL FIELD The present invention relates to a fungicidal material for virile filamentous fungi used in a substantially closed system. Conventional technology A type of mold, virile filamentous fungi, floats everywhere in the air, and even when they fall onto a clear glass surface such as a lens, they absorb moisture in the air, germinate, and grow mycelia. It stretches and spreads over the glass surface, deteriorating the optical performance of the lens. In particular, if this mold grows on the inner surface (surfaces other than the first and final surfaces) of a lens system consisting of multiple lens elements such as a photographic lens, the mirror copper must be decomposed in order to wipe it off. Therefore, in Japanese Patent Publication No. 26-3234, a vaporizable anti-fungal material such as paraform is supported on a carrier such as collodion or methacrylic polymer, or dissolved in paper, etc., and this is disposed inside an optical instrument. Therefore, a method has been proposed in which the growth of mold is prevented by gradual decomposition and transpiration of the paraform. However, there are practical problems due to the toxicity and irritation of paraform. Furthermore, α-bromocinnamaldehyde is known as a transpiration-prone antifungal material, and although this has little toxicity and odor, it has a problem with chemical stability. Purpose and Structure of the Invention The present invention has been made in view of the above-mentioned problems, and its purpose is to have low toxicity and irritation;
The object of the present invention is to provide an anti-mildew material that is chemically stable and has an excellent anti-mildew effect against fertile filamentous fungi over a long period of time. In order to achieve the above object, the present inventor repeatedly conducted various experiments, and as a result, the present inventors developed a paint selected from epoxy resin paint, urethane paint, and acrylic paint containing a phenol compound selected from orthophenylphenol and tribromophenol. It was discovered that materials coated with paint have low toxicity and irritation, and when used in a substantially closed system, an excellent anti-mildew effect against fertile fungi can be obtained over a long period of time. It was reached. To explain in more detail, the present inventor found that among various substances with transpiration properties, orthophenylphenol and tribromophenol are less toxic and irritating and have a special deterrent power against fertile filamentous fungi. They also discovered that when evaporated from the surface of the carrier, the internal phenol compound moves toward the surface, allowing for long-term sustained transpiration, and that a long-term anti-mildew effect can be expected, leading to the present invention. Furthermore, when the phenol compound used in the present invention is blended with various carriers, particularly epoxy resin paints, urethane paints, and acrylic paints, it will not be excessively released into the air.
Therefore, even if a paint carrying a phenolic compound used in the present invention is applied to a closed space such as a lens barrel, the phenolic compound may dissipate excessively and reach supersaturation, or may precipitate on the lens surface and damage the lens. It never gets dirty. Moreover, the phenol compound according to the present invention has the effect of inhibiting the growth of fertile filamentous fungi even at low concentrations. Orthophenylphenol has been generally known as a fungicide, but the present inventor has discovered that orthophenylphenol is effective against virile filamentous fungi, especially Aspergillus penicilloides, which grows on lenses.
Particularly effective against Aspergillus restrictus, Eurotium tonophyllum, and Eurotium amsterodami, it is dispersed in molecular form in the paint resin, and slight molecular movement ensures that the concentration of orthophenylphenol in the paint film is constantly uniform. They discovered that the paint has a strong tendency to move, and also evaporates moderately from the paint film surface. Orthophenylphenol evaporates from the paint film surface until the surface atmosphere reaches saturation. Therefore, the vapor pressure of orthophenylphenol near the paint film surface is
The vapor concentration is 0.5 to 1 x 10 ^-3 mmHg/20°C, so although it is extremely low for mold prevention, it is sufficient to prevent the germination and growth of virile fungi that are harmful to lenses, etc. It was enough. The same can be said for tribromophenol. Other antibacterial or antifungal phenolic compounds also have a boiling point of 210℃~
Compounds at 300°C, such as tert-butylphenol (bp; 232°C), para-tert-butylphenol (bp; 237°C), 4-isopropyl-3-methylphenol (bp; 244°C), 2-isopropyl-5 -Methylphenol (bp; 233
°C), 6-tert-butyl-3-methylphenol (bp; 244 °C), 2-tert-butyl-4-methylphenol (bp; 250 °C), 2-tert-butyl-6-methylphenol (bp; 230℃), 3,5-ditertiarybutyl-
Good results can also be obtained with 4-hydroxytoluene (bp; 265°C) at high concentrations or in the early stages. However, orthophenylphenol and tribromophenol are found to be particularly effective in terms of antifungal action based on transpiration action and durability of the effect. On the other hand, since the resin used as the carrier is used as a coating material, a relatively hard resin is preferable to which the phenol compound is relatively difficult to migrate in order to maintain evaporation properties over a long period of time. Suitable paint vehicle resins include acrylic resins such as ethylene-acrylic acid copolymer resins, ethylene-methacrylic acid copolymer resins, polyacrylate resins, polyurethane resins, and epoxy resins. The blending amounts of the phenol compound and paint vehicle resin are 5 to 30 parts by weight for the former and 95 to 70 parts by weight for the latter. A phenol compound can be blended into a paint by heating and melting it in advance into a resin, or by dissolving both in a suitable solvent (for example, a mixed solvent of isopropanol and toluene). Alternatively, the paint may be prepared by sufficiently kneading the pigment and the dispersing resin in advance. For these paint preparation methods, common techniques in the paint field may be used. The transpiration-resistant antifungal material of the present invention is used in substantially sealed systems where virile filamentous fungi can easily grow and once they grow, it is difficult to remove them, such as camera lenses, the inside of various packaging materials, the inside of container cases, pipes, etc. be able to. In a non-sealed system, the concentration of the phenol compound in the system cannot be maintained at an effective concentration, so in practice, sufficient anti-mildew effects cannot be obtained in areas other than the application area. The present invention will be explained below with reference to Examples. Examples Various combinations of the drug (phenol compound) and carrier according to the present invention and their effects will be explained below. Example Group A All Example Group A described below has a melting point of 56°C and a boiling point of 284°C as a drug (phenol compound).
It uses white crystal orthophenylphenol (hereinafter abbreviated as OPP). As OPP, Bayer Japan's product name "Preventol O. Extra" was used. Examples 1 to 6 In Examples 1 to 6, OPP was used as a two-component curing epoxy resin paint (trade name "Epora #2000" manufactured by Nippon Tokushu Toyo Co., Ltd.) and a two-component curing urethane paint (manufactured by Million Paint Co., Ltd.). Product name: Milliurethane-676-24-
150'') and room temperature drying acrylic paint (trade name ``Concrete 82'' from Million Paint Co., Ltd.).The compositions of Examples 1 and 2 are shown in Table 1, and the compositions of Examples 3 and 4 are The configuration is shown in Table 2, Example 5,
The configurations of No. 6 are shown in Table 3.

[Table] Examples 1 and 2 are obtained by weighing, mixing, and stirring the above predetermined amounts. When painting, this is sprayed onto the surface to be painted (for example, the inner surface of a lens barrel) and then baked and dried at 60°C for 20 minutes.

[Table] Examples 3 and 4 are obtained by weighing, mixing and stirring the above predetermined amounts. When painting, this is sprayed onto the surface to be painted (for example, the inner surface of a lens barrel) and then dried at room temperature for three days.

[Table] Comparative Example Group B This Comparative Example Group B (Comparative Examples 101 to 106) is the OPP of Example Group A (Examples 1 to 6) that obtained good results in a screening test, with a melting point of 112°C and a boiling point of 244°C. 4-℃
Since it is a substitute for isopropyl-3-methylphenol and the manufacturing method and structure are the same as those for OPP, the explanation thereof will be omitted. As 4-isopropyl-3-methylphenol, the product name "Frecide" manufactured by Sumitomo Chemical Co., Ltd. was used. Example Group C This Example Group C (Examples 201 to 206) uses the OPP of Example Group A (Examples 1 to 6) with a melting point of 91°C and a
2,4,6-tribromophenol having a boiling point of 290°C is used instead, and the manufacturing method and structure are the same as those for OPP, so the explanation thereof will be omitted. 2,
As 4,6-tribromophenol, TBP manufactured by Versicol, USA was used. Comparative Example Group D This Comparative Example Group D (Comparative Examples 301 to 306) uses 2(3)-tert-butyl with a melting point of 60°C and a boiling point of 270°C, which obtained good results in a screening test using the OPP of Example Group A. -4-Hydroxyanisole is used instead, and the manufacturing method and structure are the same as those for OPP, so the explanation thereof will be omitted. 2(3)−
As tert-butyl-4-hydroxyanisole, BHA manufactured by Ueno Pharmaceutical Co., Ltd. was used. Comparative Example Group E Para-carboxybutyl phenol (trade name "Metskins B" manufactured by Ueno Pharmaceutical Co., Ltd.) with a melting point of 71°C and a boiling point of 350°C, which is conventionally known as a fungicide, was added to the OPP of Example Group A. Comparative Examples 401 to 406, which were used instead, are listed for comparison of effects. Test method and results Plate culture method First, 3 g of malt extract, 3 g of yeast extract, 5 g of peptone, 500 g of glucose, and 20 g of agar were heated and dissolved in 1 part of distilled water, sterilized by boiling, and poured into a Petri dish with a diameter of 90 mm to cool and solidify. A plate culture medium with high osmotic pressure was prepared. Next, in mid-June, the above-mentioned culture medium was placed in a storage room of an ordinary house for 1 hour, and fallen bacteria were collected and cultured at 28°C for 2 weeks. The large number of colonies that emerged were all fertile molds, and these were isolated and cultured on the same medium to obtain a large number of bacterial strains. Among them, the following four types of molds, which were identified as typical ferrophilic filamentous fungi and obligate ferrophilic filamentous fungi, were used as test bacteria. Aspergillus penicilloides speg Aspergillus restrictus smith Eurotium tonophyllum otsuki Eurotium amsterodami mung These bacteria are homologous bacteria registered and preserved in IFO.
Compared to IFO-8155 Alpergillus penicilloides and IFO-8157 Eurotium tonophyllum, the growth rate, germination ability on glass surfaces, and ascospore formation were significantly more vigorous. A mixed suspension of spores or conidia of the four types of field-collected bacteria in sterile water was sprayed onto the plate medium. The Petri dish in which this medium was suspended was inverted, the upper side was used as the medium, the antifungal material specimen was placed on the lower side, and cultured in a constant temperature chamber at 28°C. The results are shown in Table 4. "-" indicates that no mycelium was observed on the medium after 6 weeks, and "-" indicates that the suppressive effect was observed at the beginning, but colonies expanded over time. "+" was recorded, and those in which vigorous growth was observed with the same or slight difference from the case where no specimen was placed were recorded as "+". Anti-mold specimens are prepared by applying paint containing an anti-mold agent to both sides of a slide glass, then storing it at room temperature for 3 days or
It was prepared by drying at 60°C for 20 minutes.

[Table] As is clear from Table 4, in Comparative Examples 401 to 406, almost no antifungal effect was obtained, whereas in the Examples of the present invention, no mycelial growth was observed and excellent antifungal effects were obtained. It can be seen that it has a fungal effect. Glass surface culture method for mixed bacteria: Mix and suspend the spores or conidia of the four types of field-collected bacteria in a 1% aqueous solution of sterilized yeast extract, apply this to a part of the surface of a clean slide glass, and loosely cap it. Place the anti-mildew test piece in a 70ml mayonnaise bottle and store at 90-94% RH and 28±2℃.
The cells were cultured in a constant temperature and humidity chamber. The surface of the slide glass where the bacterial suspension has been applied will soon dry up, leaving faint traces of the application, but if the antifungal effect is not present, germination will occur after 3 to 4 days, and eventually the mycelium will spread over the entire surface of the application. After one month, it begins to spread to the uncoated slide glass surface. In such cases, ``++'' indicates that the hyphae have spread only in the applied area even after two months, ``+'' indicates that the hyphae have not grown even after germination, and ``-'' indicates that the hyphae do not grow. ” is recorded in Table 5.

[Table] As is clear from Table 5, in this test, Example A group, Comparative example group B, Example C group, Comparative example D
It can be seen that the antifungal effect of the group is superior to that of the comparative example E group. Monobacterial glass culture method A colony of any one of the bacteria collected in the field in the previous period, cultured on the plate medium, is punched out along with the agar using a cork borer with a diameter of 3 mm, and the colony is attached to approximately the center of a clean glass slide. This is cultured together with the test piece in a mayonnaise bottle under the same conditions as above. If the mycelium growing on the surface of the attached disk-shaped agar with a diameter of 3 mm has dried up and turned brown, "-" is indicated, and if it remains as it is without drying, "±" indicates 6 weeks. In Table 6, the case where the hyphae started to extend toward the surrounding area within the same period was recorded as "+", and the case where the elongated hyphae spread to the slide glass surface was recorded as "++".

[Table] As is clear from Table 6, it can be seen that Example Group A using OPP as a drug and Example Group C using 2,4,6-tribromophenol as a drug are superior. In addition, it can be seen that better effects can be obtained by mixing these with the resin. Heat History Method In order to accelerate the effectiveness of each Example and Comparative Example after aging, the mayonnaise bottle containing only the sample pieces was kept warm at 70°C for one week, and after cooling to room temperature,
The wall of the bottle was carefully wiped with tissue paper, and a glass slide inoculated with bacteria was placed and cultured. 1
``++'' indicates that the bacteria continues to grow on the slide glass surface after 2 months, ``+'' indicates that the bacteria has spread only to the inoculated area after 2 months, and hyphae do not extend even after germination. "±" indicates "-" if no germination.
Table 7 shows what was recorded as .

[Table] As is clear from Table 7, Example Group A using OPP as a drug and Example Group C using 2,4,6-tribromophenol as a drug are superior. Furthermore, compared to the method in which OPP is used by dissolving it in a methanol solution or the like, the present invention uses OPP or tribromophenol by blending it into a paint, especially an epoxy resin paint, a urethane paint, or an acrylic paint that has excellent durability. Therefore, more sustainability can be obtained. Furthermore, we used a mixture of the following agents, which were conventionally known as anti-mold agents, with polyamide resin, ethylene-vinyl acetate copolymer, or nitrified cotton under hot melting conditions, and a mixture of methyl ethyl ketone, isobutanol, and toluene. Blends under phase solution were manufactured to have a drug content of 20%, and tests similar to those described above were conducted using these molded bodies or paints, but in each case, the above-mentioned problem that propagated on the lens occurred. No antibacterial activity against virulent fungi was observed. In addition, similar tests were conducted using paper impregnated with 200 mg/1 ml of the following agents using methanol, benzene, or dimethyl sulfoxide as a solvent, but no antibacterial properties were observed in either case. 2-(4-thiazolyl)benzimidazole 2-methoxycarbonylamino-benzimidazole Tetrachloro-isophthalonitrile Manufactured by Bayer AG, trade name "Priventol A3"
and "A4" manufactured by R.T. Vanderbilt, product name "Vanside 89" manufactured by I.C.
"CRL" manufactured by Abbott, trade name "Amical 48" manufactured by Taiko Pharmaceutical Co., Ltd., trade name "SPS" The paints of the above embodiments may be applied to an appropriate area on the inner surface of the lens barrel. Furthermore, the inside of the storage case for storing cameras and lenses may be coated with the above paint. Also, the first lens system
In order to prevent mold from forming on the front and final surfaces, the above paint may be applied to a position facing the lens surface of a lens cap or rear cap attached to the lens. Furthermore, a lens or a camera body may be stored in a bag printed with the above-mentioned example paint. Furthermore, in order to prevent mold such as pentalism inside the camera body, the above paint may be applied or a coated molded body may be placed on the inner surface of the body near the optical surface. Examples 7 to 9 and Comparative Examples 1 to 4 OPP content 20% by weight in the paints shown in Table 8
The anti-mildew material 4 impregnated with the following was applied to the outer surface of the frame 1 of a camera lens and stored at 50° C. for 50 days. Thereafter, a solution 5 in which spores or conidia of the same four types of field-collected bacteria as used in Examples 1 to 6 were mixed and suspended in sterilized water was placed on the surface of the lens G4, 2.
Inoculated with a brush and placed in a high humidity atmosphere (85%RH, 28%
The cells were placed in a plastic case (hereinafter referred to as the "high humidity case") kept at a temperature of Aspergillus penicilloides speg Aspergillus restrictus smith Eurotium tonophyllum otsuki Eurotium amsterodami mang The observation results are shown in Table 8. High humidity case Large plastic case (parts box, internal dimensions 42 x 32
x 15cm) and a small plastic case (lens box, 25 x 18 x
5 cm) were installed. Place a PVC plate with many holes (φ6) as an insole on top of it, attach a rear cap to the lens on top of it, and attach the front lens G1, 3.
I set it up so that the lens was facing upwards (the aperture was wide open and the distance was set to infinity). Then I covered the inner lid with a PVC plate, and then put the lid on the case (a thermohygrometer was also installed along with the lens). Observation method When observing, remove the lens from the high humidity case.
Observation was made using a condenser lamp. As for observation items, the state of mold growth on the fungus-inoculated single lens 2 was observed according to the following evaluation criteria. −: No growth (0 on polished clean surface or double surface)
±: Slight proliferation (〃1
(less than 1%) +: Slight proliferation (〃 1
~30%): Significant proliferation (〃4
~80%): Proliferates all over the surface (〃9
more than that)

【table】

[Table] Effects As described above, according to the present invention, there is little toxicity and irritation, and a sufficient antifungal effect against fertile filamentous fungi can be maintained for a long period of time.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a camera lens used in Examples 7 to 9 and Comparative Examples 1 to 4. 1: Ball frame (made of plastic) inside the lens barrel coated with anti-mildew material, 2: Single lens G4 inoculated with bacteria, 3: Front lens G1, 4: Anti-mildew material, 5:
Bacteria (brush inoculation).

Claims (1)

[Claims] 1. Preferably used in a substantially closed system coated with a paint selected from epoxy resin paints, urethane paints, and acrylic paints containing a phenol compound selected from orthophenylphenol and tribromophenol. Transpiration-resistant antifungal material for viscous filamentous fungi. 2. The anti-mildew material according to claim 1, which is coated with a paint containing 5 to 30% by weight of a phenol compound.