JP7672152B2 - Membrane material and method for producing the same - Google Patents

Description

The present invention relates to a membrane material and a method for producing the same.

In the Great East Japan Earthquake that occurred in Japan on March 11, 2011, ceilings of buildings with large spaces such as gymnasiums collapsed, causing damage and the loss of lives in some facilities. In order to prevent damage caused by ceiling collapse during earthquakes, Japan amended the Building Standards Act Enforcement Order in July 2013, and in August of the same year, issued a series of technical standards notices related to measures against ceiling collapse (Ministry of Land, Infrastructure, Transport and Tourism Notice No. 771 of 2013, etc.) (effective from April 1, 2014). As a result, if a building falls under the category of a "special ceiling," it is mandatory to take measures to prevent falling in accordance with these technical standards. In response to these developments, membrane ceilings made of glass fiber fabric, which is fireproof and relatively light, have been attracting attention in recent years.

A glass cloth for membrane ceilings is known which is made by weaving warp and weft yarns, one of which is a non-bulky glass fiber yarn and the other is a bulky glass fiber yarn, the sum of the weave density of the non-bulky glass fiber yarn and the weave density of the bulky glass fiber yarn is 80 to 93 threads/25 mm, the ratio (B/A) of the weave density A of the non-bulky glass fiber yarn and the weave density B of the bulky glass fiber yarn is 0.65 to 0.95, the weave structure of the glass cloth is a double weave, and the opening ratio of the glass cloth is 0.02 to 1.0% (see, for example, Patent Document 1). This glass cloth for membrane ceilings uses bulky glass fiber yarn, has a double weave structure, and has a specific weaving density, which gives it excellent sound absorption properties, including excellent sound absorption in the low frequency range that is the frequency range of human voices, and is said to suppress echoes of human voices when used as a ceiling membrane.

A sound-absorbing noncombustible sheet is also known, which is a laminate comprising a fiber fabric woven from multifilament yarn as an air-permeable diffusion layer, and at least one side of the fiber fabric is coated with a thermoplastic resin layer, and a large number of ventilation holes having a diameter of 0.5 to 2.5 mm are formed and scattered over the entire surface of the laminate, the total area of the ventilation holes has an open area ratio of 2.5 to 12.5% per unit area of the laminate, and the thermoplastic resin layer contains thermally expandable particles in an amount of 1.5 to 10% by mass relative to the thermoplastic resin layer. This sheet provides a noncombustible interior material with sound-absorbing properties as a ceiling area component and sound-absorbing component installed on the ceiling of a building, or as an accessory to a ceiling area component, and these membrane materials are lightweight and flexible so that they are unlikely to cause serious human damage even if they collapse due to an earthquake, while also having excellent echo suppression and sound attenuation effects. For this reason, the sheet is said to be widely usable as a membrane ceiling in indoor stadiums, gymnasiums, indoor pools, event halls, public halls, wedding and funeral halls, station lobbies, airport lobbies, shopping mall atriums, etc.

WO2014/171188 Brochure JP 2016-186533 A

The glass cloth for membrane ceilings disclosed as an example in Patent Document 1 is made only of woven glass fibers and does not contain resin. Therefore, there are problems in that the surface smoothness is inferior and the ability to remove dirt once attached to the membrane material (hereinafter sometimes abbreviated as "anti-fouling property") is inferior.

On the other hand, the sound-absorbing non-combustible sheet of Patent Document 2 has stain-resistant properties because it contains resin on the surface of the glass fibers. In order to enhance sound absorption, the membrane material of the membrane ceiling is designed to have a specific aperture ratio. However, after investigation, the inventors found that the membrane material of Patent Document 2 has a problem in that, when installed as a membrane ceiling for an indoor pool, for example, it is not possible to suppress the growth of mold, resulting in a poor appearance.

Therefore, the main objective of the present invention is to solve the above problems and provide a membrane material for membrane ceilings that has excellent sound absorption, stain resistance, and mold resistance, even when installed as a membrane ceiling for an indoor pool, for example.

After investigations, the inventors found that the membrane material of Patent Document 2 has air vents with a specific porosity ratio to provide excellent sound absorption, but that the presence of these air vents makes it particularly susceptible to mold. Specifically, the inventors found that water that evaporates from the pool and comes into contact with the membrane ceiling tends to accumulate in the small air vents in the membrane ceiling, making it easy for mold to grow from these air vents. In other words, the inventors found that a membrane material with excellent sound absorption properties that has air vents requires particularly high antifungal performance, more specifically, antifungal performance to the extent that no hyphae growth is observed after four weeks in a mold resistance test measured in accordance with JIS Z 2911-2018 7 wet method.

Here, if one wishes to simply impart high antifungal performance to the film material, it is conceivable to increase the amount of antifungal agent. However, when increasing the amount of antifungal agent, it is necessary to also increase the amount of resin that serves as the binder component of the antifungal agent. The inventors have found that if the amount of binder resin increases excessively, the air holes necessary for achieving excellent sound absorption performance are filled with the resin, resulting in poor sound absorption performance. In addition, it has been found that if the total organic matter amount (g/ ^m2 ) including the antifungal agent and the resin that serves as the binder component is left unchanged, the amount of resin is relatively reduced, and the amount of antifungal agent is relatively increased, the smoothness of the resulting film material is likely to be poor, and antifouling properties cannot be maintained. In other words, it has been found that there is a trade-off between sound absorption performance, antifouling properties, and antifungal performance.

Therefore, the inventors have conducted extensive research and found that, in a membrane material containing glass fiber fabric and a resin contained on the upper surface of the glass fiber, the amount of resin that achieves both antifouling and sound absorption can be set to 20 to 60 g/ ^m2 , and the antifungal agent contained in the resin is present in a relatively large amount on the surface side of the resin, thereby making it possible for the first time to simultaneously achieve sound absorption, antifouling, and the high antifungal performance required when the material is installed as a membrane ceiling for an indoor pool, for example. The present invention was completed based on this knowledge and through further research.

That is, the present invention provides the following aspects.
Item 1. A membrane material used as a membrane ceiling in a building,
Glass fiber fabric;
A resin that coats glass fibers constituting the glass fiber fabric;
A fungicide contained in the resin,
The membrane material has an air permeability of 1 to 40 cm ³ /cm ² /sec;
The total mass of the resin is 20 to 60 g/ ^m2 ,
A membrane material in which no mycelium growth is observed even after 4 weeks of incubation in a mold resistance test measured in accordance with the wet method described in the column "7. Testing of Textile Products" of the Japanese Industrial Standards JIS Z 2911-2010 "Mold Resistance Test Method."
Item 2. The membrane material according to Item 1, wherein the antifungal agent is a pyridine-based antifungal agent.
Item 3. The membrane material according to item 1 or 2, wherein the resin comprises a polyurethane-based resin, and an ethylene-vinyl acetate copolymer and/or a vinyl chloride-(meth)acrylic acid ester copolymer.
Item 4. A membrane ceiling comprising the membrane material according to any one of items 1 to 3.
Item 5. Use of the membrane material according to any one of items 1 to 3 as a membrane ceiling.
Item 6. A method for producing the membrane material according to any one of items 1 to 3, comprising the following steps (1) to (3):
(1) A step of preparing a glass fiber fabric.
(2) A first resin application step of applying a resin to the surface of the glass fibers constituting the glass fiber fabric to obtain an intermediate membrane material.
(3) A second resin adhering step of adhering a resin having a higher content of antifungal agent than the resin adhered in the first resin adhering step to the intermediate membrane material.

According to the present invention, it is possible to provide a membrane material for membrane ceilings that has excellent sound absorption, anti-fungal and anti-fouling properties, even when installed as a membrane ceiling for an indoor swimming pool, for example.

The membrane material of the present invention is a membrane material used as a membrane ceiling in a building, comprising a glass fiber fabric, a resin coating the glass fibers constituting the glass fiber fabric, and a fungicide contained in the resin, characterized in that the membrane material has an air permeability of 1 to 40 ^cm3 / ^cm2 /sec, the total mass of the resin is 20 to 60 g/ ^m2 , and no growth of mycelium is observed even after 4 weeks of culture in a fungal resistance test measured in accordance with the wet method described in the column "7. Testing of Textile Products" of Japanese Industrial Standards JIS Z 2911-2010 "Fungal Resistance Test Method." The constituent members of the membrane material of the present invention will be described in detail below.

<Glass fiber fabric>
The membrane material of the present invention contains a glass fiber fabric. This makes it easier to improve fire resistance while making the membrane material of the present invention relatively lightweight when used for a membrane ceiling, and also improves sound absorption properties.

The glass material constituting the glass fiber is not particularly limited, and any known glass material can be used. Specific examples of glass materials include alkali-free glass (E glass), acid-resistant alkali-containing glass (C glass), high-strength, high-elasticity glass (S glass, T glass, etc.), and alkali-resistant glass (AR glass).

The form of the glass fibers (warp and weft) constituting the glass fiber fabric is not particularly limited, and examples thereof include long fibers such as monofilaments and multifilaments, and short fibers such as spun yarns. Among them, from the viewpoint of improving the bonding between two sheets of fabric to be bonded to increase the area of the membrane material of the present invention, it is preferable that the yarn is a yarn in which multiple long fibers are twisted together. Furthermore, from the viewpoint of effectively adjusting the gaps between the warp threads and the weft threads even with a relatively low weaving density and making it easier to improve the sound absorption and non-flammability when the membrane material is used as a membrane ceiling, the glass fibers constituting the glass fiber fabric are preferably a ply-twisted yarn in which multiple of the above yarns are twisted together in the opposite direction to the twist direction of the yarn, and more preferably a ply-twisted yarn in which 2 to 4 of the above yarns are twisted together in the opposite direction to the twist direction of the yarn. The number of twists (number of first twists) of the ply-twisted yarn is preferably 2 to 5 times/25 mm, and more preferably 3.0 to 4.5 times/25 mm. The glass fibers constituting the glass fiber fabric may be bulky-textured yarns obtained by processing the above-mentioned yarns to be bulky with an air jet or the like. Among the bulky-textured yarns, a bulky-textured yarn obtained by processing a double-twisted yarn obtained by twisting a plurality of the above-mentioned yarns in the direction opposite to the twisting direction of the yarns to be bulky with an air jet or the like is preferable. Among the above-mentioned bulky-textured yarns, from the viewpoint of further achieving both the suppression of wrinkles in the membrane material, sound absorption properties, and non-flammability, a bulky-textured yarn obtained by twisting a double-twisted yarn obtained by twisting 2 to 4 of the above-mentioned yarns twisted in the S direction or Z direction in the direction opposite to the yarns to be bulky with an air jet or the like is more preferable.

The combination of warp and weft threads in glass fiber fabrics is not particularly limited, but examples include a combination in which the warp and weft threads are both twisted yarns, or a combination in which one of the warp and weft threads is a twisted yarn and the other is a bulky processed yarn.

The number of single fibers in the yarn is not particularly limited, but is preferably 30 to 800, and more preferably 100 to 800. The diameter of the single fiber in the yarn is, for example, 3.0 to 12.0 μm, and preferably 5.0 to 9.0 μm. The yarn count is, for example, 10 to 1000 tex, and preferably 100 to 500 tex.

When the above-mentioned ply-twisted yarn is used as the glass fiber yarn constituting the glass fiber fabric, the yarn count can be, for example, 50 to 500 tex, preferably 50 to 200 tex, and more preferably 100 to 180 tex. When the above-mentioned bulky-textured yarn is used as the glass fiber yarn constituting the glass fiber fabric, the yarn count can be, for example, 100 to 500 tex, preferably 200 to 400 tex, and more preferably 250 to 350 tex.

In the present invention, the weave of the glass fiber fabric is not limited, and examples thereof include plain weave, satin weave, twill weave, basket weave, rib weave, warp double weave, weft double weave, double weave, etc. Among these, plain weave is preferred from the viewpoint of further suppressing the occurrence of wrinkles and swelling of the membrane material and further enhancing the aesthetic appearance when used as a membrane ceiling.

In the present invention, the weave density of the glass fiber fabric is not particularly limited. For example, it can be appropriately adjusted for the purpose of further improving the non-combustibility and sound absorption when made into a membrane ceiling, and for example, 10 to 200 threads/25 mm can be mentioned, 10 to 100 threads/25 mm can be mentioned preferably, and 15 to 40 threads/25 mm can be mentioned more preferably. In this case, if the interval between the gaps between the warp threads and the gaps between the weft threads are set to 0.5 mm or less, it is easier to make the non-combustibility better. In addition, the ratio of the weave density of the warp threads to the weft threads (weave density of the weft threads/weave density of the warp threads) can be 0.50 to 0.99, preferably 0.75 to 0.99, and more preferably 0.94 to 0.99, from the viewpoint of further improving the sound absorption when made into a membrane ceiling.

In the present invention, from the viewpoint of achieving superior sound absorption when the membrane material is used for a membrane ceiling, the glass fiber fabric preferably has a cover factor of 2000 to 2400, more preferably 2100 to 2300. In the present invention, the cover factor Cf of the glass fiber fabric is a value calculated according to the following formula.
Cf=T×(DT) ^1/2 +W×(DW) ^1/2 ...(Formula 1)
Here, T and W respectively indicate the warp density and weft density (threads/25 mm) of the fabric, and DT and DW respectively indicate the counts (dtex) of the warp and weft threads constituting the fabric.

The mass of the glass fiber fabric used in the present invention is not particularly limited, but from the viewpoint of further improving the fire resistance, sound absorption and stain resistance when made into a membrane ceiling, it is 250 to 500 g/ ^m2 , and more preferably 300 to 400 g/ ^m2 .

The glass fiber fabric used in the present invention may contain polyvinyl alcohol and/or starch on the surface. Polyvinyl alcohol and/or starch are used, for example, as sizing agents for glass fiber fabrics, and can usually be removed (de-oiled) by a heat cleaning process in which heat treatment is performed at a temperature of about 400°C. On the other hand, in the present invention, by using a glass fiber fabric from which the sizing agent has not been removed, i.e., a glass fiber fabric that has not been subjected to a heat cleaning process, the mechanical strength of the membrane material can be further improved.

<Resin>
The membrane material of the present invention includes a resin that covers the glass fibers that constitute the above-mentioned glass fiber fabric. That is, the membrane material of the present invention includes a resin that is included on the upper surface of the above-mentioned glass fibers. If the membrane material is made of only glass fiber fabric, as in the membrane material disclosed as an example in Patent Document 1, it is difficult to remove dirt such as dust that has entered the gaps between the single fibers in the glass fibers by wiping it off. On the other hand, according to the membrane material of the present invention, since the surface of the glass fibers is covered with a resin, the intrusion of dirt into the gaps between the single fibers in the glass fibers is reduced, and the smoothness of the membrane material is improved, making it possible to obtain a membrane material with excellent anti-fouling properties. In addition, in the membrane material of the present invention, the resin also plays a role in adjusting the size of the gaps (openings) formed by the warp and weft threads of the glass fiber fabric, thereby making the membrane material excellent in sound absorption. Furthermore, in the membrane material of the present invention, the resin also plays a role in preventing water that has evaporated from the pool and come into contact with the membrane ceiling from accumulating in the gaps between the single fibers in the glass fibers, and preventing mold from easily occurring from the gaps between the glass fibers.

The type of resin used in the film material of the present invention is not particularly limited. Examples of resins include curable resins such as vinyl ester resins, urethane acrylate resins, fluorene acrylate resins, and unsaturated polyester resins; vinyl chloride resins (including homopolymers of vinyl chloride and copolymers of vinyl chloride and other monomers); acrylic resins (including polymers and copolymers of acrylic acid, acrylic acid esters, acrylamide, acrylonitrile, methacrylic acid, methacrylic acid esters, etc.); polyurethane resins, fluorine resins, ethylene-vinyl acetate copolymers, saturated polyester resins, and polyamide resins. These resins may be used alone or in combination of two or more. Among these resins, polyurethane resins, fluorine resins, ethylene-vinyl acetate copolymers, vinyl chloride resins, and acrylic resins are preferred from the viewpoint of achieving better antifouling properties, and it is more preferred to use polyurethane resins in combination with ethylene-vinyl acetate copolymers and/or vinyl chloride-(meth)acrylic acid ester copolymers. That is, when a membrane material is used to form a membrane ceiling, the membrane material may be enlarged in area, and the enlargement is usually achieved by bonding the membrane materials together by heat welding or the like. Polyurethane resins are preferred in that they can further improve the bonding property by heat welding and the antifouling property. Ethylene-vinyl acetate copolymers and vinyl chloride-(meth)acrylic acid ester copolymers are preferred in that they can improve the water repellency of the membrane material while improving the bonding property, and can easily prevent water that has evaporated from the pool and contacted the membrane ceiling from accumulating in the gaps (openings) formed by the warp and weft of the glass fiber fabric. Therefore, by using polyurethane resins in combination with ethylene-vinyl acetate copolymers and/or vinyl chloride-(meth)acrylic acid ester copolymers, the bonding property by heat welding, the antifouling property, and the antifungal property can be further improved.

When a polyurethane resin is used in combination with an ethylene-vinyl acetate copolymer and/or a vinyl chloride-(meth)acrylic acid ester copolymer as the resin, the ratio of the total amount of the ethylene-vinyl acetate copolymer and/or the vinyl chloride-(meth)acrylic acid ester copolymer contained in the membrane material of the present invention to 100 parts by mass of the total amount of the polyurethane resin contained in the membrane material of the present invention is, for example, 5 to 500 parts by mass, preferably 5 to 400 parts by mass.

In the present invention, a polyurethane resin is a resin having a urethane bond in the repeating unit of the main chain. Examples of isocyanate components constituting a polyurethane resin include aliphatic diisocyanates such as ethylene diisocyanate, hexamethylene diisocyanate, and decamethylene diisocyanate, alicyclic diisocyanates such as xylylene diisocyanate, bis(isocyanomethyl)cyclohexane, hydrogenated diphenylmethane diisocyanate, and hydrogenated tolylene diisocyanate, diisocyanate compounds such as aromatic diisocyanates such as phenylene diisocyanate, tolylene diisocyanate, diphenylmethane diisocyanate, dimethyldiphenylene diisocyanate, and naphthylene diisocyanate, and isocyanate compounds such as isophorone diisocyanate, 1,3-cyclohexane diisocyanate, tetramethylene diisocyanate, and triphenylmethane triisocyanate. Examples of the polyol component constituting the polyurethane resin include polyester polyols, polyether polyols, polycarbonate polyols, polyesteramide polyols, and acrylate polyols.

The total mass of the resin in the film material of the present invention is 20 to 60 g/m ^2. If the total mass of the resin is less than 20 g/m ² , the antifouling property is inferior. If the total mass of the resin is more than 60 g/m ² , the gaps formed by the warp and weft of the glass fiber fabric become too small, resulting in poor air permeability and poor sound absorption. From the viewpoint of further achieving the sound absorption, antifungal properties, antifouling properties, and non-flammability of the film material, the total mass of the resin in the film material of the present invention is preferably 20 to 50 g/m ² , more preferably 30 to 50 g/m ^2. In the present invention, the "total mass of the resin" refers to the total mass of all the resins that coat the glass fiber. For example, when two or more resin layers are provided as the resin that coats the glass fiber as described later, the total mass of the resin contained in all the resin layers.

In the membrane material of the present invention, the ratio of the total mass of resin (g/ ^m2 ) to the mass of glass fiber fabric (g/ ^m2 ) (total mass of resin/mass of glass fiber fabric) is, for example, 0.05 to 0.2. From the viewpoint of achieving even greater balance between sound absorption, antifungal properties, and antifouling properties of the membrane material, the ratio (total mass of resin/mass of glass fiber fabric) is preferably 0.08 to 0.15.

In the film material of the present invention, the ratio of the total mass of the resin (g/ ^m2 ) to the total mass of the film material (g/ ^m2 ) (total mass of the resin/total mass of the film material) is, for example, 0.05 to 0.2. From the viewpoint of achieving even greater balance between the sound absorption, antifungal and antifouling properties of the film material, the ratio (total mass of the resin/total mass of the film material) is preferably 0.08 to 0.12.

<Antifungal agent>
In the film material of the present invention, the resin coating the glass fiber fabric contains an antifungal agent. As described above, in a film material having excellent sound absorption properties due to the provision of voids (openings), mold is likely to grow, so it is necessary to have a particularly high antifungal performance, more specifically, the antifungal performance described below. Therefore, in order to provide the film material of the present invention with high antifungal performance, the resin coating the glass fiber fabric contains an antifungal agent.

There are no particular limitations on the type of antifungal agent, but a suitable example is a pyridine-based antifungal agent. A pyridine-based antifungal agent is an antibacterial agent whose main component is a pyridine compound. Examples of pyridine compounds include 2-pyridylthiol-1-oxide zinc, 2-chloro-4-trichloromethyl-6-(2-furylmethoxy)pyridine, 2-chloro-4-trichloromethyl-6-methoxypyridine, 2-chloro-6-trichloromethylpyridine, di(4-chlorophenyl)pyridylmethanol, 2,3,5-trichloro-4-(n-propylsulfonyl)pyridine, 2-pyrindinethiol-1-oxide sodium, 1,4-(1-diiodomethylsulfonyl)benzene, 10,10'-oxybisphenoxyarsine, 6-(2-thiophenecarbonyl)-1H-2-benzimidazolecarbamic acid methyl ester, and 5-chloro-2-methyl-4-isothiazolin-3-one. These pyridine-based fungicides may be used alone or in combination of two or more. Among these pyridine-based antifungal agents, 2-pyridylthiol-1-zinc oxide is preferred from the viewpoint of realizing antifungal properties excellent in resistance to moist heat.

In the film material of the present invention, the total mass (g/ ^m2 ) of the antifungal agent is not particularly limited as long as it satisfies the antifungal properties described below, and may be, for example, 0.5 to 3.0 g/ ^m2 . From the viewpoint of achieving a better balance between sound absorption, antifungal properties, antifouling properties, and non-flammability of the film material, the total mass (g/ ^m2 ) of the antifungal agent is preferably 1.0 to 3.0 g/ ^m2 , and more preferably 1.5 to 2.5 g/ ^m2 . In the present invention, the "total mass of the antifungal agent" refers to the total mass of the antifungal agent contained in the resin coating the glass fiber, and for example, when two or more resin layers are provided as the resin coating the glass fiber as described below, it refers to the total mass of the antifungal agent contained in all of the resin layers.

In the film material of the present invention, the ratio of the total mass (g/ ^m2 ) of the antifungal agent to the total mass (g/ ^m2 ) of the resin (antifungal agent/resin) is, for example, 0.010 to 0.100. From the viewpoint of achieving an even better balance between the sound absorption properties, antifungal properties, antifouling properties, and non-flammability of the film material, the ratio (antifungal agent/resin) is preferably 0.030 to 0.070, and more preferably 0.040 to 0.060.

<Other ingredients>
The film material of the present invention may contain other components in addition to the antifungal agent in the resin, such as additives including a crosslinking agent, a coloring pigment such as an organic pigment or an inorganic pigment, a dye, an ultraviolet absorber, and an infrared absorber.

<Membrane material structure>
The membrane material of the present invention has a structure in which the glass fibers constituting the glass fiber fabric are covered with a resin containing a fungicide. In addition, in order to provide the membrane material of the present invention with breathability and excellent sound absorption properties as described below, at least a part of the gap formed by adjacent warp yarns and adjacent weft yarns in the glass fiber fabric is not completely covered with the resin, and an opening (vent) is formed.

<Layer structure of resin coating glass fiber>
In the membrane material of the present invention, the resin coating the glass fiber may form a single resin layer, or may form two or more resin layers (preferably a two-layer structure or a three-layer structure) using resin compositions having different compositions.

In the membrane material of the present invention, when the resin coating the glass fiber forms two or more resin layers, it is sufficient that at least one of the resin layers contains an antifungal agent, but it is preferable that at least the resin layer arranged on the outermost surface of the membrane material contains an antifungal agent. In particular, when the resin coating the glass fiber forms two or more resin layers, it is preferable that the content ratio of the antifungal agent in the resin layer arranged on the outermost surface of the membrane material is higher than the average content ratio of the antifungal agent in the other resin layers. That is, in the membrane material of the present invention, it is preferable that the resin coating the glass fiber has a portion in which the content ratio of the antifungal agent differs in the thickness direction of the resin, and the content ratio is highest on the surface side of the resin. By adopting such a configuration, it is possible to preferably provide the antifungal properties described below and to fully provide the antifungal performance required when installed as a membrane ceiling of an indoor pool.

In the membrane material of the present invention, when the resin coating the glass fiber forms two or more resin layers, the constituent resin of the resin layer disposed on the outermost surface (the surface opposite the glass fiber) may be any of the resins exemplified above, but preferably contains a polyurethane-based resin. By forming a resin layer disposed on the outermost surface using a polyurethane-based resin, the bonding property and antifouling property of the membrane material can be further improved.

In the membrane material of the present invention, when the resin coating the glass fiber forms two or more resin layers, the content ratio of the antifungal agent in the resin layer arranged on the outermost surface (mass of antifungal agent contained in the resin layer arranged on the outermost surface/mass of resin contained in the resin layer arranged on the outermost surface) is preferably 0.060 to 0.30, more preferably 0.080 to 0.30, and even more preferably 0.100 to 0.250.

In the membrane material of the present invention, when the resin coating the glass fiber forms two or more resin layers, the ratio of the mass of the resin contained in the resin layer arranged on the outermost surface to the mass of the glass fiber fabric (mass of the resin contained in the resin layer arranged on the outermost surface/mass of the glass fiber fabric) is, for example, 0.005 to 0.04, preferably 0.01 to 0.03.

In addition, in the membrane material of the present invention, when the resin coating the glass fiber forms two or more resin layers, the constituent resin of the resin layer arranged other than the outermost surface may be any of the resins exemplified above, but preferably contains a polyurethane-based resin, and more preferably contains a polyurethane-based resin and an ethylene-vinyl acetate copolymer and/or a vinyl chloride-(meth)acrylic acid ester copolymer. In this way, at least one layer of the resin layer arranged other than the outermost surface is formed of a resin layer containing a polyurethane-based resin and an ethylene-vinyl acetate copolymer and/or a vinyl chloride-(meth)acrylic acid ester copolymer, thereby improving the water repellency of the membrane material and making it more antifungal, while also providing the membrane material with excellent flexibility, making it easier to prevent wrinkles from occurring during construction of the membrane ceiling.

In the film material of the present invention, when the resin coating the glass fiber forms two or more resin layers, the average content ratio of the antifungal agent in the resin layers arranged other than the outermost surface (total mass of the antifungal agent contained in all resin layers arranged other than the outermost surface/total mass of the resin contained in all resin layers arranged other than the outermost surface) is, for example, 0 to 0.05, preferably 0.01 to 0.04, and more preferably 0.02 to 0.04. Here, the average content ratio is the ratio of the mass of the resin contained in the resin layer to the mass of the antifungal agent contained in the resin layer when there is one resin layer arranged other than the outermost surface. In addition, when there are two or more resin layers arranged other than the outermost surface, the average content ratio is the ratio of the total mass of the resin contained in all resin layers arranged other than the outermost surface (two or more resin layers) to the total mass of the antifungal agent contained in all resin layers arranged other than the outermost surface (two or more resin layers).

In the membrane material of the present invention, when the resin coating the glass fiber forms two or more resin layers, the ratio of the mass of the resin contained in the resin layers arranged other than the outermost surface to the mass of the glass fiber fabric (total mass of the resins included in the resin layers arranged other than the outermost surface/mass of the glass fiber fabric) is, for example, 0.05 to 0.15, preferably 0.05 to 0.12. Here, when there is one resin layer arranged other than the outermost surface, the ratio is the ratio of the mass of the glass fiber fabric to the mass of the resin contained in that resin layer. When there are two or more resin layers arranged other than the outermost surface, the ratio is the ratio of the mass of the glass fiber fabric to the total mass of the resin contained in all of the resin layers arranged other than the outermost surface (two or more resin layers).

In addition, in the film material of the present invention, when the resin coating the glass fiber forms two or more resin layers, the content ratio of the antifungal agent in the resin layer arranged on the outermost surface (mass of antifungal agent contained in the resin layer arranged on the outermost surface/mass of resin contained in the resin layer arranged on the outermost surface) is preferably 3 to 10 times higher, and more preferably 5 to 10 times higher, than the content ratio of the antifungal agent in the other resin layers (total mass of antifungal agent contained in all resin layers arranged other than the outermost surface/total mass of resin contained in all resin layers arranged other than the outermost surface).

<Characteristics of membrane materials>
(1) Air permeability The membrane material of the present invention has an air permeability of 1 to 40 cm ³ /cm ² /sec. By setting the air permeability within this range, the sound absorbing property of the membrane material can be excellent. As described above, if the amount of resin and the amount of antifungal agent are increased simply to improve the stain resistance and antifungal property, the gaps formed by adjacent warp yarns and adjacent weft yarns constituting the glass fiber fabric are filled, and the air permeability becomes less than 1 cm ³ /cm ² /sec, resulting in a membrane material with poor sound absorbing property. If the amount of resin is reduced or the weaving density of the glass fiber fabric is too low, the air permeability exceeds 40 cm ³ /cm ² /sec, resulting in a membrane material with poor sound absorbing property. The air permeability is more preferably 3 to 20 cm ³ /cm ² /sec, further preferably 6 to 15 cm ³ /cm ² /sec, and particularly preferably 8 to 15 cm ³ /cm ² /sec. The air permeability is a value measured and calculated according to the method described in "7.13 Air permeability of cloth" of the Japanese Industrial Standard JIS R 3420:2013 "General test method for glass fibers".

To achieve the breathability of the membrane material within the above range, the mass of resin used, the weave density of the glass fiber fabric, the count of the glass fibers, etc. can be adjusted appropriately.

(2) Antifungal properties The film material of the present invention is one in which no mycelium growth is observed even after 4 weeks of culture in a mold resistance test measured according to the wet method described in "7. Testing of Textile Products" of the Japanese Industrial Standards JIS Z 2911-2010 "Mold Resistance Test Method". As described above, the film material of the present invention contains an antifungal agent on the surface side of the resin, so that even if the film material is a film material with excellent sound absorption properties as the above-mentioned breathability, it can ensure high antifungal properties necessary for installation as a membrane ceiling of an indoor pool, while also being excellent in antifouling properties.

In order to impart the above-mentioned anti-fungal properties, it is sufficient to include an anti-fungal agent on the surface side of the resin, but this can be more easily achieved by appropriately adjusting the type and mass (g/ ^m2 ) of the anti-fungal agent and the composition of the resin (mass, type, etc.).

(3) Non-flammability: From the viewpoint of providing excellent non-flammability, the membrane material of the present invention preferably satisfies the following requirements.
<Requirements>
According to "4.10.2 Box Test Method" of the "Fire Resistance Testing and Evaluation Procedures" (revised on March 1, 2014) of the General Incorporated Foundation Building Materials Testing Center (a Japanese corporation), a heat generation test is conducted in which radiant heat of 50 kW/ ^m2 is irradiated onto the surface of the membrane material from a radiant electric heater. In the heat generation test, the maximum heat generation rate does not exceed 200 kW/ ^m2 for 10 seconds or more for 20 minutes after the start of heating, and the total heat generation amount for 20 minutes after the start of heating is 8 MJ/ ^m2 or less. In the heat generation test, it is preferable that there are no through holes of 0.5 mm square or more for 20 minutes after the start of heating.

In order to ensure that the membrane material of the present invention meets the above-mentioned non-flammability requirements, for example, the amount of resin may be adjusted or a flame retardant may be added to the resin.

(4) Sound Absorption Properties In addition, from the viewpoint of achieving superior sound absorption properties when used in a membrane ceiling, the membrane material of the present invention preferably has an NRC (Noise Reduction Coefficient) value measured according to the method in accordance with Japanese Industrial Standard JIS A 1409:1998 "Method of measuring sound absorption coefficient in a reverberation room" of 0.5 or more, and more preferably 0.6 to 0.9.

The specific method for measuring the NRC value is as follows. According to Japanese Industrial Standard JIS A 1409:1998 "Method for measuring reverberation room sound absorption coefficient", the reverberation room sound absorption coefficient is measured at 250 Hz, 500 Hz, 1000 Hz, and 2000 Hz. The reverberation room sound absorption coefficient is measured in an irregular heptahedral reverberation chamber (room volume 264 ^m3 , total indoor surface area 247 ^m2 ) with six microphones and two sound sources. The reverberation room sound absorption coefficient is measured using a reverberation room sound absorption coefficient measuring device and white noise as the measurement noise. The membrane material to be measured is cut to 3000mm x 3640mm (sample area ^10.92m2 ) and attached in a reverberation chamber with a back air layer thickness of 300mm by the method of Type E-300 described in Appendix D (Regulation) "Method of mounting a sample for sound absorption coefficient test" of Japanese Industrial Standard JIS A 1409:1998 "Method of measuring sound absorption coefficient in a reverberation chamber". In this state, the reverberation chamber sound absorption coefficient is measured at 250Hz, 500Hz, 1000Hz, and 2000Hz under the conditions of temperature 24.7℃ and relative humidity 59.6%. In addition, in the calculation of the reverberation chamber sound absorption coefficient, correction is made for the temperature and humidity conditions of the air using formula (6) described in Appendix E (Reference) "Method of correcting the effect of temperature and relative humidity changes in a reverberation chamber on the reverberation time" of Japanese Industrial Standard JIS A 1409:1998 "Method of measuring sound absorption coefficient in a reverberation chamber". The average value of the reverberation room sound absorption coefficients at 250 Hz, 500 Hz, 1000 Hz, and 2000 Hz is defined as the NRC value.

In order for the membrane material of the present invention to have the above-mentioned NRC value, for example, it is sufficient to adjust the breathability, but it is also possible to more easily achieve the above-mentioned NRC value by adjusting the cover factor of the glass fiber fabric and the amount of resin attached to the surface of the constituent glass fibers.

(5) Other physical properties, etc. The ignition loss of the membrane material of the present invention is not particularly limited, but from the viewpoint of making it easier to simultaneously achieve sound absorption, antifouling properties, nonflammability, and the bondability between two woven fabrics to be bonded to a large area when the membrane material is used for a membrane ceiling, it is preferably 5 to 20 mass%, more preferably 8 to 17 mass%, and even more preferably 8 to 13 mass%. The ignition loss is a value measured according to the method described in "7.3.2 Ignition loss" of the Japanese Industrial Standard JIS R 3420:2013 "General test method for glass fibers".

The thickness of the membrane material of the present invention is not particularly limited, but may be, for example, 0.2 to 0.8 mm, preferably 0.3 to 0.8 mm, and more preferably 0.3 to 0.7 mm. The mass (g/ ^m2 ) of the membrane material of the present invention is not particularly limited, but may be, for example, 100 to 1000 g/ ^m2 , preferably 200 to 600 g/ ^m2 , and more preferably 300 to 450 g/ ^m2 .

<Method of manufacturing the membrane material of the present invention>
The method for producing the membrane material of the present invention is not particularly limited as long as it can produce a membrane material having the above-mentioned configuration, but a suitable example is a method in which the following steps (1) to (3) are carried out in this order. By adopting such a method, the membrane material of the present invention can be easily produced, and a membrane material that has excellent antifouling properties by ensuring the resin mass necessary for antifouling properties and also has excellent antifungal properties can be obtained.
(1) A step of preparing a glass fiber fabric.
(2) A first resin application step of applying a resin to the surface of the glass fibers constituting the glass fiber fabric to obtain an intermediate membrane material.
(3) A second resin adhering step of adhering a resin having a higher content of antifungal agent than the resin adhered in the first resin adhering step to the intermediate membrane material.

(1) Step of preparing glass fiber fabric In this step, the above-mentioned glass fiber fabric is prepared. The glass fiber fabric may be prepared by weaving glass fibers, or may be prepared by purchasing a commercially available product.

(2) First Resin Adhering Step In the first resin adhering step, a resin is adhered to the surface of the glass fibers constituting the glass fiber fabric, to produce a membrane material intermediate in which the surface of the glass fibers is coated with a resin layer arranged on all surfaces except the outermost surface.

As described above, the resin used in the first resin adhesion process may be any resin capable of forming a resin layer disposed on any surface other than the outermost surface, and may have a lower content of antifungal agent than the resin used in the second resin adhesion process described below.

In the first resin adhesion process, examples of methods for adhering the resin include preparing a resin composition solution of the desired composition, impregnating the glass fiber fabric, adjusting the amount of adhesion using a nip roll or knife, etc., and drying.

In addition, when forming three or more resin layers as the resin coating the glass fiber, the first resin attachment step may be performed two or more times using the same or different resin composition solutions to attach the resin to the surface of the glass fiber.

(3) Second Resin Adhesion Step In the second resin adhesion step, a resin having a higher content of antifungal agent than the resin adhered in the first resin adhesion step is adhered to the membrane material intermediate obtained in the first resin adhesion step, thereby obtaining the membrane material of the present invention.

The resin used in the second resin adhesion process may be any resin capable of forming a resin layer disposed on the outermost surface as described above, and may have a higher content of antifungal agent than the resin adhered in the first resin adhesion process.

In the second resin attachment process, methods for attaching the resin include, for example, preparing a resin composition solution of the desired composition, impregnating the membrane material intermediate obtained in the first resin attachment process, adjusting the amount of attachment using a nip roll, knife, etc., and drying.

<Membrane material applications>
The membrane material of the present invention has excellent sound absorption, antifungal, and antifouling properties, and is used as a membrane ceiling. A membrane ceiling is a ceiling material installed on the ceiling of a building. The type of ceiling membrane on which the membrane material of the present invention is installed is not particularly limited, but examples thereof include ceiling membranes for indoor pools, indoor stadiums, gymnasiums, shopping malls, ceremonial halls, station lobbies, airport lobbies, etc.

The present invention will be described in detail below with reference to examples and comparative examples. However, the present invention is not limited to the examples.

[Evaluation method]
1. Warp and weft count (tex)
Measurements and calculations were performed according to the method described in "7.1 Count" of the Japanese Industrial Standard JIS R 3420 2013 "General Test Methods for Glass Fibers."

2. Single fiber diameter (μm) of glass fibers constituting the warp and weft threads
Twenty warp yarns and 20 weft yarns were randomly selected, and the diameters of all the single fibers (the largest part) of the 20 yarns were measured and the average value was calculated to obtain the single fiber diameter.

3. Warp and weft density (threads/25mm)
The weave density of the warp and weft yarns was measured and calculated according to the method described in "7.9 Density (weave density)" of the Japanese Industrial Standard JIS R 3420 2013 "General test method for glass fibers".

4. Thickness (mm)
Measured and calculated according to Method A described in "7.10.1 Cloth thickness" of the Japanese Industrial Standard JIS R 3420 2013 "General test methods for glass fibers".

5. Mass of glass fiber fabric, mass of membrane material (g/ ^m2 )
Measurements were performed and calculations were performed according to the method described in "7.2 Mass (mass) of cloth and mat" in the Japanese Industrial Standard JIS R 3420 2013 "General test methods for glass fibers."

6. Ignition loss (mass%)
Measurement and calculation were performed according to the method described in "7.3.2 Ignition loss" of Japanese Industrial Standard JIS R 3420:2013 "General test methods for glass fibers".

7. Non-flammability According to "4.10.2 Box test method" of the "Fireproof performance test and evaluation procedure manual" (revised on March 1, 2014) of the General Incorporated Foundation Construction Materials Testing Center, a heat generation test was conducted by irradiating the surface of the membrane material with 50 kW/ ^m2 of radiant heat from a radiant electric heater. In the heat generation test, if all three requirements (I) to (III) below were satisfied, the material was rated as A (pass), and if even one was not satisfied, the material was rated as B (fail).
(I) Within 20 minutes after the start of heating, the maximum heat generation rate does not exceed 200 kW/ ^m2 for 10 seconds or more.
(II) The total heat generation amount within 20 minutes after the start of heating is 8 MJ/ ^m2 or less.
(III) After 20 minutes from the start of heating, there are no through holes of 0.5 mm square or more.

8. Breathability ( ^cm3 / ^cm2 /sec)
Measurements were performed and calculated according to the method described in "7.13 Air permeability of cloth" of the Japanese Industrial Standard JIS R 3420:2013 "General test method for glass fibers".

9. Sound Absorption The NRC value was determined according to Japanese Industrial Standard JIS A 1409:1998 "Method of measuring sound absorption coefficient in a reverberation room." The specific measuring method is as follows.

The reverberation room sound absorption coefficient was measured in an irregular heptahedral reverberation room (room volume 264 m ³ , total surface area 247 m ² ) with six microphones and two sound sources. The reverberation room sound absorption coefficient was measured using a reverberation room sound absorption coefficient measuring device (AERevSys Alphas-LAB, manufactured by Nihon Onkyo Engineering Co., Ltd.) and white noise as the measurement noise. The membrane material to be measured was cut to 3000 mm x 3640 mm (sample area 10.92 m ² ) and attached in the reverberation room with a back air layer thickness of 300 mm by the method of Type E-300 described in Appendix D (regulations) "Method of mounting a sample for sound absorption coefficient test" of Japanese Industrial Standard JIS A 1409:1998 "Method of measuring reverberation room sound absorption coefficient". In this state, the reverberation room sound absorption coefficients were measured at 250 Hz, 500 Hz, 1000 Hz, and 2000 Hz under the conditions of a temperature of 24.7°C and a relative humidity of 59.6%. The calculation of the reverberation room sound absorption coefficient was carried out by using formula (6) described in "Method of correcting the effect of changes in temperature and relative humidity in a reverberation room on the reverberation time" in Appendix E (Reference) of the Japanese Industrial Standard JIS A 1409:1998 "Method of measuring reverberation room sound absorption coefficient", and the correction was made based on the temperature and humidity conditions of the air. The average value of the reverberation room sound absorption coefficients at 250 Hz, 500 Hz, 1000 Hz, and 2000 Hz was taken as the NRC value.

10. Antifouling properties According to the method described in the Japanese Industrial Standard JIS K 5600-5-4:1999 "General Test Methods for Paints-Part 5: Mechanical Properties of Coatings-Section 4 Scratch Hardness (Pencil Method)", a pencil scratch tester and a pencil with hardness HB (trade name Uni, manufactured by Mitsubishi Pencil Co., Ltd.) were used to draw a line of about 50 mm in length by moving the pencil back and forth 10 times at an angle of 45° on the film material under a load of 750 gf. Next, an eraser (trade name "High Polymer Eraser Ain", manufactured by Pentel Co., Ltd.) was used to rub the line 10 times in a perpendicular direction under a load of 500 g, and the pencil marks were evaluated as "A" if the pencil marks were not noticeable, and "B" if the pencil marks were noticeable.

11. Mildew Resistance The mildew resistance was measured according to the wet method described in the "7. Testing of Textile Products" section of the Japanese Industrial Standard JIS Z 2911-2010 "Mold Resistance Testing Method." Specifically, a test piece of the membrane material cut to 5 cm length and 5 cm width was attached to the surface of a plate medium (agar 20 g/L, ammonium nitrate 3 g/L, potassium dihydrogen phosphate 1 g/L, magnesium nitrate heptahydrate 0.5 g/L, potassium chloride 0.25 g/L, iron (II) nitrate heptahydrate 0.002 g/L, purified water balance) prepared in a petri dish, and 1 mL of a mixed spore suspension of fungi (mixed spore suspension of Aspergillus niger NBRC 105649, Penicillium citrinum NBRC 6352, Chaetomium globosum NBRC 6347, and Myrothecium verrucaria NBRC 6113) was evenly sprayed onto the surface of the test piece and the medium, and the petri dish was covered and placed in a place maintained at a temperature of 26 ± 2°C for 28 days. The growth of mold on the test pieces was observed 7, 14, 21 and 28 days after the start of the culture.

[Production of membrane material]
Example 1
(1) Preparation of glass fiber fabric First, a twisted yarn (product name ECDE75 1/2 3.8S) manufactured by Unitika Glass Fiber Co., Ltd. was prepared as the warp and weft. The warp and weft were woven in a plain weave structure with a warp density of 31 threads/25 mm and a weft density of 30 threads/25 mm to obtain a glass fiber fabric. The ignition loss of the glass fiber fabric was 1.0 mass%, the cover factor was 2241, the thickness was 0.296 mm, and the mass was 346.5 g/ ^m2 . Since the heat cleaning treatment was not performed, the glass fiber fabric contained polyvinyl alcohol and starch as sizing agents.

The twisted yarn used as the warp and weft threads is a twisted yarn made by twisting two strands of a yarn (number of single fibers in one yarn: 800, diameter of single fiber: 6 μm) twisted 0.7 times/25 mm in the Z direction to a further twist of 3.8 times/25 mm, in the opposite direction to the twist direction of the yarn, at 3.8 times/25 mm, and the yarn count of the twisted yarn is 135 tex.

(2) First resin attachment step (2-1) 1st time The obtained glass fiber fabric was impregnated with a resin composition solution having the following formulation, the amount of attachment was adjusted using a nip roll or the like, and the fabric was dried at a temperature of 150° C. for 3 minutes to perform the first first resin attachment step. In the membrane material intermediate obtained in the first first resin attachment step, the mass of the attached resin composition (resin and antifungal agent) was 5.9 g/ ^m2 , and the content ratio of the antifungal agent (antifungal agent/resin) was 0.143.
(Prescription)
Polyurethane resin dispersion (30% solids): 64 parts by weight Ethylene-vinyl acetate copolymer dispersion (56% solids): 42 parts by weight Mildewproofing agent (pyridine-based mildewproofing agent) (100% solids): 6.1 parts by weight Pure water: 743.6 parts by weight Total: 855.7 parts by weight

(2-2) Second Time The film material intermediate obtained in the first first resin adhesion step was impregnated with a resin composition solution of the following formulation, the adhesion amount was adjusted using a nip roll or the like, and the film was dried at a temperature of 150°C for 3 minutes to perform the second first resin adhesion step. In the second first resin adhesion step, the mass of the adhered resin was 22.6 g/ ^m2 , and the content ratio of the antifungal agent (antifungal agent/resin) was 0. In addition, in the film material intermediate obtained through the first and second first resin adhesion steps, the mass of the resin composition was 28.5 g/ ^m2 , and the average content ratio of the antifungal agent (antifungal agent mass/resin mass) was 0.027.
(Prescription)
Polyurethane resin dispersion (solid content 30%): 100 parts by weight Pure water: 73.1 parts by weight Total: 173.1 parts by weight

(3) Second resin adhesion step The membrane material intermediate obtained in the second first resin adhesion step was impregnated with a resin composition solution of the following formulation, the adhesion amount was adjusted using a nip roll or the like, and the membrane material was obtained by drying at a temperature of 150°C for 3 minutes. The mass of the resin composition adhered in the second resin adhesion step was 8.4 g/ ^m2 , and the content ratio of the antifungal agent adhered in the second resin adhesion step (antifungal agent mass/resin mass) was 0.140.
(Prescription)
Polyurethane resin dispersion (solid content 30%): 100 parts by weight Antifungal agent (pyridine-based antifungal agent) (solid content 100%): 4.2 parts by weight Pure water: 337.7 parts by weight Total: 441.9 parts by weight

In addition, in the obtained membrane material, the total mass of resin was 35.1 g/ ^m2 ; the ratio of the total mass of resin (g/ ^m2 ) to the mass of glass fiber fabric (g/ ^m2 ) (total mass of resin/mass of glass fiber fabric) was 0.10; the ratio of the total mass of resin (g/ ^m2 ) to the total mass of membrane material (g/ ^m2 ) (total mass of resin/total mass of membrane material) was 0.09; the total mass of the anti-mold agent was 1.8 g/ ^m2 ; the ratio of the total mass of resin (g/ ^m2 ) to the total mass of the anti-mold agent (g/ ^m2 ) (anti-mold agent/resin) was 0.050; the mass of the membrane material was 383.4 g/ ^m2 ; and the thickness of the membrane material was 0.346 mm.

Example 2
(1) Preparation of glass fiber fabric First, warp and warp yarns (product name ECDE75 1/2 3.8S) manufactured by Unitika Glass Fiber Co., Ltd. were prepared. The above warp and weft yarns were woven in a plain weave structure so that the warp density was 31 threads/25 mm and the weft density was 30 threads/25 mm to obtain a glass fiber fabric. The ignition loss of the glass fiber fabric was 1.0 mass%, the cover factor was 2241, the thickness was 0.296 mm, and the mass was 346.5 g/ ^m2 . Since no heat cleaning treatment was performed, the glass fiber fabric contained polyvinyl alcohol and starch as sizing agents.

The twisted yarn used as the warp and weft threads is a twisted yarn made by twisting two strands of a yarn (number of single fibers in one yarn: 800, diameter of single fiber: 6 μm) twisted 0.7 times/25 mm in the Z direction to a further twist of 3.8 times/25 mm, in the opposite direction to the twist direction of the yarn, at 3.8 times/25 mm, and the yarn count of the twisted yarn is 135 tex.

(2) First Resin Adhesion Step (2-1) First Time The obtained glass fiber fabric was impregnated with a resin composition solution having the following formulation, the amount of adhesion was adjusted with a nip roll, a knife, or the like, and the fabric was dried at a temperature of 150° C. for 3 minutes to perform the first first resin adhesion step. The mass of the resin composition (resin and antifungal agent) adhered in the first first resin adhesion step was 5.9 g/ ^m2 , and the content ratio of the antifungal agent (mass of antifungal agent/mass of resin) was 0.143.
(Prescription)
Polyurethane resin dispersion (30% solids): 64 parts by weight Ethylene-vinyl acetate copolymer (56% solids): 42 parts by weight Mildewproofing agent (pyridine-based mildewproofing agent) (100% solids): 6.1 parts by weight Pure water: 743.6 parts by weight Total: 855.7 parts by weight

(2-2) Second Time The membrane material intermediate obtained in the first first resin adhesion step was impregnated with a resin composition solution of the following formulation, the adhesion amount was adjusted with a nip roll, a knife, etc., and the second first resin adhesion step was performed by drying at a temperature of 150°C for 3 minutes. The mass of the resin adhered in the second first resin adhesion step was 27.3 g/m ² , and the content ratio of the antifungal agent (antifungal agent mass/resin mass) was 0. The mass of the resin composition in the membrane material intermediate obtained through the first and second first resin adhesion steps was 33.2 g/m ² , and the content ratio of the antifungal agent (antifungal agent mass/resin mass) was 0.023.
(Prescription)
Polyurethane resin dispersion (solid content 30%): 100 parts by weight Pure water: 40.9 parts by weight Total: 140.9 parts by weight

(3) Second resin adhesion step The membrane material intermediate obtained in the second first resin adhesion step was impregnated with a resin composition solution of the following formulation, the adhesion amount was adjusted with a nip roll, a knife, etc., and the second resin adhesion step was performed by drying at a temperature of 150°C for 3 minutes to obtain a membrane material. The mass of the resin composition adhered in the second resin adhesion step was 10.4 g/ ^m2 , and the content ratio of the antifungal agent adhered in the second resin adhesion step (antifungal agent mass/resin mass) was 0.203.
(Prescription)
Polyurethane resin dispersion (solid content 30%): 100 parts by weight Antifungal agent (pyridine-based antifungal agent) (solid content 100%): 6.1 parts by weight Pure water: 337.7 parts by weight Total: 441.9 parts by weight

In addition, the total mass of resin in the membrane material was 41.1 g/ ^m2 ; the ratio of the total mass of resin (g/ ^m2 ) to the mass of glass fiber fabric (g/ ^m2 ) (total mass of resin/mass of glass fiber fabric) was 0.12; the ratio of the total mass of resin (g/ ^m2 ) to the total mass of the membrane material (g/ ^m2 ) (total mass of resin/total mass of membrane material) was 0.11; the total mass of the anti-mold agent was 2.5 g/ ^m2 ; the ratio of the total mass of resin (g/ ^m2 ) to the total mass of the anti-mold agent (g/ ^m2 ) (anti-mold agent/resin) was 0.061; the mass of the membrane material was 390.1 g/ ^m2 , and the thickness of the membrane material was 0.345 mm.

Example 3
(1) Preparation of glass fiber fabric First, a twisted yarn manufactured by Unitika Glass Fiber Co., Ltd. (product name ECDE75 1/2 3.8S; single fiber diameter 6 μm, 135 tex) was prepared as a warp yarn, and a bulky processed yarn manufactured by Unitika Glass Fiber Co., Ltd. (product name TDE300; single fiber diameter 6 μm, 305 tex) was prepared as a weft yarn. The above warp and weft yarns were woven in a plain weave structure so that the warp density was 31/25 mm and the weft density was 18/25 mm to obtain a glass fiber fabric. The ignition loss of the glass fiber fabric was 1.0% by mass, the cover factor was 2133, the thickness was 0.45 mm, and the mass was 390.0 g/m ^2. Since no heat cleaning treatment was performed, the glass fiber fabric contained polyvinyl alcohol and starch as sizing agents.

The twisted yarn used as the warp thread is a twisted yarn made by twisting two strands of a yarn (number of single fibers in one yarn: 800, diameter of single fiber: 6 μm) twisted 0.7 times/25 mm in the Z direction to a further twist of 3.8 times/25 mm, in the opposite direction to the twist direction of the yarn, at 3.8 times/25 mm, and the yarn count of the twisted yarn is 135 tex.

The bulky textured yarn used as the weft is a bulky textured yarn obtained by processing the ply-twisted yarn described below into a bulky yarn, and the yarn count of the bulky textured yarn is 305 tex. The ply-twisted yarn is a ply-twisted yarn obtained by twisting four first twisted yarns (yarns) in which a yarn twisted 0.7 times/25 mm in the Z direction (number of single fibers in one yarn: 800, diameter of single fiber: 6 μm) is further twisted 3.8 times/25 mm in the direction opposite to the twist direction of the yarn.

(2) First resin adhesion step The obtained glass fiber fabric was impregnated with a resin composition solution having the following formula, the adhesion amount was adjusted using a nip roll, a knife, or the like, and the fabric was dried at a temperature of 150°C for 3 minutes to carry out the first resin adhesion step. The mass of the resin composition (resin and antifungal agent) adhered in the first first resin adhesion step was 40 g/ ^m2 , and the content ratio of the antifungal agent (antifungal agent mass/resin mass) was 0.031. In this Example 3, the first resin adhesion step was carried out only once.
(Prescription)
Polyurethane resin dispersion (30% solids): 24 parts by weight Vinyl chloride-acrylic acid ester copolymer emulsion (40% solids): 218 parts by weight Mildewproofing agent (pyridine-based mildewproofing agent) (100% solids): 2.9 parts by weight Pure water: 135 parts by weight Total: 232.3 parts by weight

(3) Second resin adhesion step In the second resin adhesion step, the membrane material intermediate obtained in the first resin adhesion step was impregnated with a resin composition solution of the following formulation, the adhesion amount was adjusted with a nip roll, a knife, etc., and the second resin adhesion step was performed by drying at a temperature of 150°C for 3 minutes to obtain a membrane material. The mass of the resin composition adhered in the second resin adhesion step was 10 g/ ^m2 , and the content ratio of the antifungal agent adhered in the second resin adhesion step (antifungal agent mass/resin mass) was 0.118.
(Prescription)
Polyurethane resin dispersion (solid content 30%): 28.3 parts by weight Antifungal agent (pyridine-based antifungal agent) (solid content 100%): 1 part by weight Pure water: 147 parts by weight Total: 176.3 parts by weight

In addition, the total mass of resin in the membrane material was 47.8 g/ ^m2 ; the ratio of the total mass of resin (g/ ^m2 ) to the mass of glass fiber fabric (g/ ^m2 ) (total mass of resin/mass of glass fiber fabric) was 0.12; the ratio of the total mass of resin (g/ ^m2 ) to the total mass of the membrane material (g/ ^m2 ) (total mass of resin/total mass of membrane material) was 0.11; the total mass of the anti-mold agent was 2.2 g/ ^m2 , and the ratio of the total mass of resin (g/ ^m2 ) to the total mass of the anti-mold agent (g/ ^m2 ) (anti-mold agent/resin) was 0.047; the mass of the membrane material was 440.0 g/ ^m2 , and the thickness of the membrane material was 0.600 mm.

(Comparative Example 1)
(1) Preparation of glass fiber fabric First, a twisted yarn (product name ECDE75 1/2 3.8S) manufactured by Unitika Glass Fiber Co., Ltd. was prepared as the warp and weft. The warp and weft were woven in a plain weave structure with a warp density of 31 threads/25 mm and a weft density of 30 threads/25 mm to obtain a glass fiber fabric. The ignition loss of the glass fiber fabric was 1.0 mass%, the cover factor was 2241, the thickness was 0.296 mm, and the mass was 346.5 g/ ^m2 . Since the heat cleaning treatment was not performed, the glass fiber fabric contained polyvinyl alcohol and starch as sizing agents.

The twisted yarn used as the warp and weft threads is a twisted yarn made by twisting two strands of a yarn (number of single fibers in one yarn: 800, diameter of single fiber: 6 μm) twisted 0.7 times/25 mm in the Z direction with a twist count of 3.8 times/25 mm in the opposite direction to the twist direction of the yarn, and the yarn count is 135 tex.

(2) First resin adhesion step The obtained glass fiber fabric was impregnated with a resin composition solution having the following formula, the adhesion amount was adjusted using a nip roll or the like, and the fabric was dried at a temperature of 150°C for 3 minutes to carry out the first resin adhesion step. The mass of the resin composition (resin and antifungal agent) adhered in the first resin adhesion step was 3.3 g/ ^m2 , and the content ratio of the antifungal agent (mass of antifungal agent/mass of resin) was 0.030. In this Comparative Example 1, the first resin adhesion step was carried out only once.
(Prescription)
Polyurethane resin dispersion (solid content 30%): 53 parts by weight Ethylene-vinyl acetate copolymer dispersion (solid content 56%): 60 parts by weight Mildewproofing agent (triazole-based mildewproofing agent) (solid content 50%): 3 parts by weight Pure water: 154.4 parts by weight Total: 270.4 parts by weight

(3) Second resin adhesion step The membrane material intermediate obtained in the first resin adhesion step was impregnated with a resin composition solution of the following formulation, the adhesion amount was adjusted using a nip roll or the like, and the membrane material was obtained by drying at a temperature of 150°C for 3 minutes. The mass of the resin composition adhered in the second resin adhesion step was 18.5 g/ ^m2 , and the content ratio of the antifungal agent adhered in the second resin adhesion step (antifungal agent mass/resin mass) was 0.033.
(Prescription)
Polyurethane resin dispersion (solid content 30%): 100 parts by weight Antifungal agent (triazole-based antifungal agent) (solid content 50%): 2 parts by weight Pure water: 112.6 parts by weight Total: 214.6 parts by weight

In addition, the total mass of resin in the membrane material was 21.1 g/ ^m2 ; the ratio of the total mass of resin (g/ ^m2 ) to the mass of glass fiber fabric (g/ ^m2 ) (total mass of resin/mass of glass fiber fabric) was 0.06; the ratio of the total mass of resin (g/ ^m2 ) to the total mass of the membrane material (g/ ^m2 ) (total mass of resin/total mass of membrane material) was 0.06; the total mass of the anti-mold agent was 0.7 g/ ^m2 ; the ratio of the total mass of resin (g/ ^m2 ) to the total mass of the anti-mold agent (g/ ^m2 ) (anti-mold agent/resin) was 0.033; the mass of the membrane material was 368.3 g/ ^m2 ; and the thickness of the membrane material was 0.340 mm.

(Comparative Example 2)
(1) Preparation of glass fiber fabric First, a twisted yarn manufactured by Unitika Glass Fiber Co., Ltd. (product name ECDE75 1/2 3.8S; single fiber diameter 6 μm, 135 tex) was prepared as the warp and weft. The above warp and weft were woven in a plain weave structure so that the warp density was 31/25 mm and the weft density was 30/25 mm to obtain a glass fiber fabric. The ignition loss of the glass fiber fabric was 1.0 mass, the cover factor was 2241, the thickness was 0.296 mm, and the mass was 346.5 g/ ^m2 . Since the heat cleaning treatment was not performed, the glass fiber fabric contained polyvinyl alcohol and starch as sizing agents.

The twisted yarn used as the warp and weft threads is a twisted yarn made by twisting two strands of a yarn (number of single fibers in one yarn: 800, diameter of single fiber: 6 μm) twisted 0.7 times/25 mm in the Z direction to a further twist of 3.8 times/25 mm, in the opposite direction to the twist direction of the yarn, at 3.8 times/25 mm, and the yarn count of the twisted yarn is 135 tex.

(2) First resin adhesion step The obtained glass fiber fabric was impregnated with a resin composition solution having the following formula, the adhesion amount was adjusted using a nip roll or the like, and the fabric was dried at a temperature of 150°C for 3 minutes to carry out the first resin adhesion step. The mass of the resin adhered in the first resin adhesion step was 6.4 g/ ^m2 , and the content ratio of the antifungal agent (antifungal agent mass/resin mass) was 0.030. In this comparative example 2, the first resin adhesion step was carried out only once.
(Prescription)
Polyurethane resin dispersion (solid content 30%): 53 parts by weight Ethylene-vinyl acetate copolymer dispersion (solid content 56%): 60 parts by weight Mildewproofing agent (triazole-based mildewproofing agent) (solid content 50%): 3 parts by weight Pure water: 154.4 parts by weight Total: 270.4 parts by weight

(3) Second resin adhesion step The membrane material intermediate obtained in the first resin adhesion step was impregnated with a resin composition solution of the following formulation, the adhesion amount was adjusted using a nip roll or the like, and the membrane material was obtained by drying at a temperature of 150°C for 3 minutes. The mass of the resin composition adhered in the second resin adhesion step was 21.0 g/ ^m2 , and the content ratio of the antifungal agent adhered in the second resin adhesion step (antifungal agent mass/resin mass) was 0.067.
(Prescription)
Polyurethane resin dispersion (solid content 30%): 100 parts by weight Antifungal agent (triazole-based antifungal agent) (solid content 50%): 4 parts by weight Pure water: 112.6 parts by weight Total: 216.6 parts by weight

In addition, the total mass of resin in the membrane material was 25.9 g/ ^m2 ; the ratio of the total mass of resin (g/ ^m2 ) to the mass of glass fiber fabric (g/ ^m2 ) (total mass of resin/mass of glass fiber fabric) was 0.07; the ratio of the total mass of resin (g/ ^m2 ) to the total mass of membrane material (g/ ^m2 ) (total mass of resin/total mass of membrane material) was 0.07; the total mass of the anti-mold agent was 1.5 g/ ^m2 ; the ratio of the total mass of resin (g/ ^m2 ) to the total mass of the anti-mold agent (g/ ^m2 ) (anti-mold agent/resin) was 0.058, the mass of the membrane material was 373.9 g/ ^m2 , and the thickness of the membrane material was 0.340 mm.

(Comparative Example 3)
(1) Preparation of glass fiber fabric First, a twisted yarn manufactured by Unitika Glass Fiber Co., Ltd. (product name ECDE75 1/2 3.8S) was prepared as a warp yarn, and a bulky processed yarn manufactured by Unitika Glass Fiber Co., Ltd. (product name TDE300) was prepared as a weft yarn. The above warp and weft yarns were woven in a plain weave structure so that the warp density was 31/25 mm and the weft density was 18/25 mm, to obtain a glass fiber fabric. The ignition loss of the glass fiber fabric was 1.0% by mass, the cover factor was 2233, the thickness was 0.45 mm, and the mass was 390.0 g/ ^m2 . Since no heat cleaning treatment was performed, the glass fiber fabric contained polyvinyl alcohol and starch as sizing agents.

The twisted yarn used as the warp thread is a twisted yarn made by twisting two strands of a yarn (number of single fibers in one yarn: 800, diameter of single fiber: 6 μm) twisted 0.7 times/25 mm in the Z direction to a further twist of 3.8 times/25 mm, in the opposite direction to the twist direction of the yarn, at 3.8 times/25 mm, and the yarn count of the twisted yarn is 135 tex.

The bulky textured yarn used as the weft is a bulky textured yarn obtained by processing the ply-twisted yarn described below into a bulky yarn, and the yarn count of the bulky textured yarn is 305 tex. The ply-twisted yarn is a ply-twisted yarn obtained by twisting four first twisted yarns (yarns) in which a yarn twisted 0.7 times/25 mm in the Z direction (number of single fibers in one yarn: 800, diameter of single fiber: 6 μm) is further twisted 3.8 times/25 mm in the direction opposite to the twist direction of the yarn.

(2) First resin adhesion step The obtained glass fiber fabric was impregnated with a resin composition solution having the following formula, the adhesion amount was adjusted using a nip roll, a knife, or the like, and the fabric was dried at a temperature of 150°C for 3 minutes to carry out the first resin adhesion step. The mass of the resin adhered in the first resin adhesion step was 40 g/ ^m2 , and the content ratio of the antifungal agent (antifungal agent mass/resin mass) was 0.062. In this Comparative Example 3, the first resin adhesion step was carried out only once.
(Prescription)
Polyurethane resin dispersion (30% solids): 46.7 parts by weight Vinyl chloride-acrylic acid ester copolymer emulsion (40% solids): 190 parts by weight Mildewproofing agent (pyridine-based mildewproofing agent) (100% solids): 5.6 parts by weight Pure water: 130 parts by weight Total: 372.3 parts by weight

(3) Second resin adhesion step The membrane material intermediate obtained in the first resin adhesion step was impregnated with a resin composition solution of the following formulation, the adhesion amount was adjusted with a nip roll, a knife, etc., and the second resin adhesion step was performed by drying at a temperature of 150°C for 3 minutes to obtain a membrane material. The mass of the resin composition adhered in the second resin adhesion step was 10 g/ ^m2 , and the content ratio of the antifungal agent adhered in the second resin adhesion step (antifungal agent mass/resin mass) was 0.
(Prescription)
Polyurethane resin dispersion (solid content 30%): 100 parts by weight Pure water: 400 parts by weight Total: 500 parts by weight

In addition, the total mass of resin in the membrane material was 47.7 g/ ^m2 ; the ratio of the total mass of resin (g/ ^m2 ) to the mass of glass fiber fabric (g/ ^m2 ) (total mass of resin/mass of glass fiber fabric) was 0.12; the ratio of the total mass of resin (g/ ^m2 ) to the total mass of the membrane material (g/ ^m2 ) (total mass of resin/total mass of membrane material) was 0.11; the total mass of the anti-mold agent was 2.3 g/ ^m2 ; the ratio of the total mass of resin (g/ ^m2 ) to the total mass of the anti-mold agent (g/ ^m2 ) (anti-mold agent/resin) was 0.049; the mass of the membrane material was 440.0 g/ ^m2 ; and the thickness of the membrane material was 0.600 mm.

[Membrane material evaluation results]
The evaluation results are shown in Tables 1 and 2.

As shown in Tables 1 and 2, the membrane materials of Examples 1 to 3 contain a glass fiber fabric, a resin that covers the glass fibers that make up the glass fiber fabric, and a fungicide contained in the resin, and have an air permeability of 1 to 40 cm ³ /cm ² /sec and a total mass of the resin of 20 to 60 g/m ^2. Furthermore, when measured according to the wet method described in the column "7. Testing of Textile Products" of the Japanese Industrial Standards JIS Z 2911-2010 "Mold Resistance Test Method", no mycelium growth was observed after 4 weeks of culture. The membrane materials of Examples 1 to 3 have excellent sound absorption, fungicide, and stain resistance, and fully meet the required performance required when installed, for example, as a membrane ceiling for an indoor pool.

On the other hand, in Comparative Examples 1 to 3, when measured in accordance with the wet method described in the "7. Testing of Textile Products" section of the Japanese Industrial Standard JIS Z 2911-2010 "Mold Resistance Test Method," mold growth was observed within 1/3 of the sample area after 4 weeks of incubation (mold growth was observed on the 14th day), indicating that the samples have poor mold prevention properties and would not be able to suppress mold growth if installed as a membrane ceiling for an indoor swimming pool.

Claims (6)

A membrane material used as a membrane ceiling in a building,
Glass fiber fabric;
A resin that coats glass fibers constituting the glass fiber fabric;
A fungicide contained in the resin,
The membrane material has an air permeability of 1 to 40 cm ³ /cm ² /sec;
The total mass of the resin is 20 to 60 g/ ^m2 ,
The resin forms two or more resin layers,
the content ratio of the antifungal agent in the resin layer disposed on the outermost surface of the film material is higher than the average content ratio of the antifungal agent in the other resin layers;
A membrane material in which no mycelium growth is observed even after 4 weeks of incubation in a mold resistance test measured in accordance with the wet method described in the column "7. Testing of Textile Products" of the Japanese Industrial Standards JIS Z 2911-2010 "Mold Resistance Test Method." The membrane material according to claim 1, wherein the fungicide is a pyridine-based fungicide. The membrane material according to claim 1 or 2, wherein the resin comprises a polyurethane resin and an ethylene-vinyl acetate copolymer and/or a vinyl chloride-(meth)acrylic acid ester copolymer. A membrane ceiling comprising the membrane material according to any one of claims 1 to 3. Use of the membrane material according to any one of claims 1 to 3 as a membrane ceiling. A method for producing the membrane material according to any one of claims 1 to 3, comprising the following steps (1) to (3):
(1) A step of preparing a glass fiber fabric.
(2) A first resin application step of applying a resin to the surface of the glass fibers constituting the glass fiber fabric to obtain an intermediate membrane material.
(3) A second resin adhering step of adhering a resin having a higher content of antifungal agent than the resin adhered in the first resin adhering step to the intermediate membrane material.