Laminated nonwoven fabric and protective clothing

Abstract

In order to provide a laminated nonwoven fabric and protective clothing having outstanding antistatic properties and water-repelling properties and as well as outstanding skin cling prevention properties, a laminated nonwoven fabric according to the present invention is constituted by a laminated nonwoven fabric having a first layer, a second layer, and a third layer in this order, wherein: the first layer is a nonwoven fabric constituting the outermost layer on one surface of the laminated nonwoven fabric, and the first layer contains an antistatic agent and a water repellent agent, the content of the antistatic agent being 0.02 to 0.50 mass% with respect to the entire first layer and the content of the water repellent agent being 0.02 to 0.50 mass% with respect to the entire first layer; the second layer is a nonwoven fabric, the average fiber diameter of the fibers constituting the second layer is 1.0 to 15.0 µm, and the second layer contains an antistatic agent and a water repellent agent, the content of the antistatic agent being less than 0.02 mass% with respect to the entire second layer and the content of the water repellent agent being less than 0.02 mass% with respect to the entire second layer; and the third layer is a nonwoven fabric constituting the outermost layer on the other side of the laminated nonwoven fabric, the fibers constituting the third layer being fibers comprising an olefin resin, the third layer containing an antistatic agent and a water repellent agent, the content of the antistatic agent being less than 0.02 mass% with respect to the entire third layer, and the tensile strength of the third layer measured according to JIS L1096-2010 being 15 N or more.

Description

Laminated nonwoven fabrics and protective clothing

[0001] The present invention relates to a laminated nonwoven fabric and a protective garment.

[0002] Conventionally, workers often wear disposable protective clothing to prevent contamination during work such as periodic repairs at waste disposal sites or manufacturing facilities. Such protective clothing is required to be water-resistant, dust-proof, durable, and comfortable to wear. Furthermore, due to the diversification of work environments, protective clothing worn during work involving the removal or handling of dust or chemical substances may be antistatically treated on the surface to prevent static electricity from adsorbing dust or chemical substances or preventing static electricity-related explosions.

[0003] Patent Document 1 discloses a method for providing a composite nonwoven fabric suitable for protective clothing, which has an excellent balance of properties, such as moisture permeability and waterproofness on the side exposed to the outside air, and strength, sweat absorption, antistatic properties, etc. on the inside due to the rayon nonwoven fabric, by combining and integrating a moisture-permeable and waterproof nonwoven fabric made of polyolefin-based ultrafine fibers, a heat-bondable nonwoven fabric made of thermoplastic elastomer ultrafine fibers, and a rayon nonwoven fabric.

[0004] Furthermore, Patent Document 2 discloses a method for providing a synthetic fiber structure that is suitable for use in sanitary materials, medical materials, clothing materials, etc., by treating the synthetic fiber structure with an aqueous solution or aqueous dispersion containing a fluorine-based water repellent, a nonionic antistatic agent, and isopropyl alcohol, and that has excellent alcohol repellency and oil repellency and water resistance.

[0005] On the other hand, Patent Document 3 discloses an antistatic protective fabric that has excellent antistatic properties and dust protection performance by laminating a fiber layer treated with an antistatic agent and an electrically charged fiber layer.

[0006] JP 2003-336155 A JP 2010-150725 A International Publication No. 2019 / 171995 A

[0007] The composite nonwoven fabric of Patent Document 1 is laminated with a rayon nonwoven fabric, which is a hydrophilic material, and exhibits antistatic properties. However, the antistatic properties are not necessarily sufficient to inhibit the adsorption of dust particles and chemical substances due to static electricity. Furthermore, when used in protective clothing, the rayon nonwoven fabric has high water absorption properties, so that the fabric sticks to the skin after sweating, which poses a problem of reducing comfort during work.

[0008] Patent Document 2 discloses that the synthetic fiber structure has improved alcohol repellency, oil resistance, and water pressure resistance by treating the synthetic fiber structure with a fluorine-based water repellent and a nonionic antistatic agent. However, the synthetic fiber structure specifically produced uses a laminated nonwoven fabric, but is produced by immersing the entire structure in a treatment solution containing a fluorine-based water repellent and a nonionic antistatic agent until it is completely impregnated, and each layer constituting the synthetic fiber structure is treated in the same manner. Therefore, the presence of the water repellent prevents the water absorbency of the antistatic agent from being fully exhibited, and the structure still absorbs water to a certain extent, resulting in an insufficient improvement in water pressure resistance. Furthermore, there is a concern that the moisture contained in the antistatic agent in the layer closest to the skin may cause increased stickiness, and the antistatic properties and high water pressure resistance may not necessarily be fully exhibited.

[0009] Patent Document 3 discloses that the antistatic dust protective fabric has excellent antistatic properties, breathability, and dust protective performance by laminating a fiber layer treated with an antistatic agent and an electrically charged fiber layer. However, the inventors have found that the fiber layer treated with the antistatic agent tends to absorb moisture, and the absorbed moisture migrates to the electrically charged fiber layer, reducing the water pressure resistance of the electrically charged fiber layer, which in turn reduces the water pressure resistance of the antistatic dust protective fabric and results in poor waterproofness.

[0010] In view of the above problems, the present invention aims to provide a laminated nonwoven fabric and protective clothing that have excellent antistatic and waterproof properties and also have excellent skin-releasing properties.

[0011] In order to solve the problems, the present invention discloses the following laminated nonwoven fabric.

[0012] (1) A laminated nonwoven fabric having a first layer, a second layer, and a third layer in this order, wherein the first layer is a nonwoven fabric constituting the outermost layer on one side of the laminated nonwoven fabric, the first layer contains an antistatic agent and a water repellent agent, the content of the antistatic agent is 0.02% by mass or more and 0.50% by mass or less relative to the entire first layer, and the content of the water repellent agent is 0.02% by mass or more and 0.50% by mass or less relative to the entire first layer, the second layer is a nonwoven fabric, the average fiber diameter of the fibers constituting the second layer is 1.0 to 15.0 μm, the second layer does not contain an antistatic agent, or even if it contains an antistatic agent, the content of the antistatic agent is less than 0.02% by mass relative to the entire second layer, and the third layer is a nonwoven fabric constituting the outermost layer on the other side of the laminated nonwoven fabric, a laminated nonwoven fabric, wherein the fibers constituting the third layer are fibers made of an olefin resin, the third layer does not contain an antistatic agent, or if it contains an antistatic agent, the content of the antistatic agent is less than 0.02 mass% with respect to the entire third layer, and the third layer has a tensile strength of 15 N or more as measured in accordance with JIS L1096-2010.

[0013] (2) The basis weight of the second layer is 1 to 30 g / m ２ The laminated nonwoven fabric according to (1) above,

[0014] (3) The surface electrical resistance value of the one surface measured in accordance with EN1149-1-2006 is 2.5 × 10 ９ The laminated nonwoven fabric according to (1) or (2), having a stiffness of Ω or less.

[0015] (4) Water pressure resistance measured according to JIS L1092-2009 is 1000 mmH ２ The laminated nonwoven fabric according to any one of (1) to (3), wherein the elastic modulus is O or more.

[0016] (5) The air permeability measured based on JIS L1913-2010 is 5 cm ３ / cm ２ / sec or more.

[0017] (6) The laminated nonwoven fabric according to any one of (1) to (5), wherein the frictional force of the other surface in a wet state measured in accordance with JIS K7125-1999 is 0.7 N or less.

[0018] (7) Protective clothing using the laminated nonwoven fabric according to any one of (1) to (6), wherein the first layer is arranged to form an outer surface of the protective clothing.

[0019] According to the present invention, it is possible to provide a laminated nonwoven fabric and protective clothing that have excellent antistatic properties and waterproof properties, and further have excellent skin-releasing properties.

[0020] First, the laminated nonwoven fabric of the present invention will be described in detail.

[0021] The laminated nonwoven fabric of the present invention has a first layer, a second layer, and a third layer in this order. The first layer is a nonwoven fabric that constitutes the outermost layer on one side of the laminated nonwoven fabric of the present invention and further contains an antistatic agent and a water repellent agent. The content of the antistatic agent is 0.02% by mass or more and 0.50% by mass or less, based on the total mass of the first layer, and the content of the water repellent agent is 0.02% by mass or more and 0.50% by mass or less, based on the total mass of the first layer. Next, the second layer is a nonwoven fabric, the average fiber diameter of the fibers constituting this second layer is 1.0 to 15.0 μm, this second layer does not contain an antistatic agent, or if it contains an antistatic agent, the content of the antistatic agent is less than 0.02 mass% relative to the entire second layer, the third layer is a nonwoven fabric that constitutes the outermost layer on the other side of the laminated nonwoven fabric of the present invention, the fibers constituting this third layer are fibers made of an olefin resin, this third layer does not contain an antistatic agent, or if it contains an antistatic agent, the content of the antistatic agent is less than 0.02 mass% relative to the entire third layer, and the tensile strength measured in accordance with JIS L1096-2010 is 15 N or more.

[0022] The above-described structure of the laminated nonwoven fabric of the present invention provides the laminated nonwoven fabric with excellent antistatic and waterproof properties, and also provides excellent skin-releasing properties. The mechanism by which the above-described effects are obtained is presumed to be as follows.

[0023] In the laminated nonwoven fabric of the present invention, the first layer contains a specific amount of antistatic agent, and the second layer contains no antistatic agent or only a very small amount, thereby achieving excellent antistatic and waterproof properties. As will be described in detail below, the antistatic agent adsorbs moisture in the air, thereby reducing surface electrical resistance and exhibiting antistatic properties. On the other hand, the inclusion of an antistatic agent makes it easier for moisture to be drawn into the laminated nonwoven fabric, promoting water penetration from the outermost surface of the laminated nonwoven fabric to the other outermost surface, thereby reducing waterproof properties. Therefore, by incorporating a hydrophobic water repellent agent together with the antistatic agent in the first layer, water penetration from the surface to the interior of the laminated nonwoven fabric is prevented. Furthermore, by incorporating no antistatic agent or only a very small amount of antistatic agent in the second layer, which has constituent fibers with a small fiber diameter and a fine mesh size, moisture penetration into the second layer, which is less susceptible to water penetration, is suppressed. Furthermore, by laminating a third layer with a tensile strength of 15 N or more onto a second layer with a fine mesh, even when water pressure is applied from one side of the laminated nonwoven fabric to the other, the laminated nonwoven fabric is less likely to deform and breakage of the second layer is suppressed, resulting in improved water pressure resistance and excellent waterproofing.

[0024] In general, antistatic agents adsorb moisture in the air as described above, which is thought to increase stickiness with the skin and cause poor release properties. Therefore, the third layer does not contain an antistatic agent, or if it does contain an antistatic agent, the content is extremely small, and it is made of fibers made of an olefin resin that has a low moisture content, i.e., is less likely to adsorb moisture in the air, so that the surface of the laminated nonwoven fabric is less likely to adsorb moisture, resulting in excellent release properties.

[0025] It is presumed that the above mechanism allows the laminated nonwoven fabric of the present invention to have excellent antistatic and waterproof properties, as well as excellent skin-releasing properties.

[0026] The laminated nonwoven fabric of the present invention may be composed only of the first layer, the second layer, and the third layer, or may include layers other than the first layer, the second layer, and the third layer as long as the effects of the present invention are not impaired. Examples of layers other than the first layer, the second layer, and the third layer include film layers, woven fabrics, knitted fabrics, etc., and examples of such laminated nonwoven fabrics include a first layer / film layer / second layer / third layer configuration. It is preferable that the laminated nonwoven fabric of the present invention be composed only of the first layer, the second layer, and the third layer, because this improves the breathability of the laminated nonwoven fabric and reduces the number of steps in the manufacturing process of the laminated nonwoven fabric, thereby improving the productivity of the laminated nonwoven fabric.

[0027] The first layer, second layer, and third layer can be laminated using a variety of methods, including a thermal bonding method using a pair of rolls, each of which has an engraved (uneven) surface, a thermal embossing roll consisting of a combination of a flat (smooth) roll and a roll with an engraved (uneven) surface, and a thermal calender roll consisting of a pair of flat (smooth) rolls, as well as ultrasonic bonding, which involves thermal welding using ultrasonic vibrations from a horn. Here, it is preferable to use a thermal embossing roll consisting of a pair of rolls, each of which has an engraved (uneven) surface, or a thermal embossing roll consisting of a combination of a flat (smooth) roll and a roll with an engraved (uneven) surface, because these methods offer excellent productivity, provide strength in the partially thermally bonded areas, and maintain the texture and feel unique to nonwoven fabrics in the non-bonded areas.

[0028] The surface electrical resistance of one surface of the laminated nonwoven fabric measured in accordance with EN1149-1-2006 is 2.5 × 10 ９ It is preferable that the surface electrical resistance is 2.5×10 Ω or less. ９ By ensuring that the resistance is Ω or less, it is possible to suppress charging by static electricity that occurs when a part of the first layer comes into contact with another part of the first layer and is worn away, or when the first layer comes into contact with an object other than the first layer and is worn away, during use of the laminated nonwoven fabric or protective clothing.

[0029] The water pressure resistance of the laminated nonwoven fabric measured according to JIS L1092-2009 is 1000 mmH ２ O (9.8 kN / m ２ ) or more, and ２ O (14.7kN / m ２ ) is more preferable. ２ O (9.8 kN / m ２ ) or more, it is possible to prevent liquid that comes into contact with the laminated nonwoven fabric from penetrating or permeating when pressure is applied.

[0030] The wet frictional force of the other surface of the laminated nonwoven fabric, measured in accordance with JIS K7125-1999, is preferably 0.7 N or less, and more preferably 0.5 N or less. A wet frictional force of 0.7 N or less prevents stickiness when in contact with the skin, satisfies good skin release properties, and provides comfort during work.

[0031] The breathability of the laminated nonwoven fabric measured according to JIS L1913-2010 is 5 cm ３ / cm ２ / sec or more, and ３ / cm ２ More preferably, it is 5 cm / sec or more. ３ / cm ２ / sec or more, when the laminated nonwoven fabric is used as protective clothing, the air on the wearer's side and the outside, separated by the laminated nonwoven fabric, can be efficiently replaced, making it possible to suppress increases in temperature and humidity in the protective clothing and providing an excellent wearing comfort. There is no upper limit to the breathability of the laminated nonwoven fabric, but it is generally a physical property that correlates with water pressure resistance, and the higher the breathability, the lower the water pressure resistance. Therefore, to set the water pressure resistance in a suitable range, a practical limit is 200 cm ３ / cm ２ It is preferable that the time is 1 / sec or less.

[0032] The laminated nonwoven fabric of the present invention can be used in protective clothing. By using the laminated nonwoven fabric in protective clothing, it is possible to prevent static electricity from being generated on the surface of the protective clothing during work, and at the same time, when sweating, it has excellent skin-releasing properties, making it comfortable to wear.

[0033] When the laminated nonwoven fabric is used in protective clothing, it is preferable that the first layer be arranged to form the outer surface of the protective clothing, and the third layer be arranged to form the inner surface of the protective clothing. By arranging the first layer to form the outer surface of the protective clothing, it is possible to improve the surface electrical resistance, which is an index of antistatic performance. Furthermore, by arranging the third layer to form the inner surface of the protective clothing, it is possible to improve the release properties of the fabric against the skin after sweating, thereby achieving greater comfort during work.

[0034] The first layer, the second layer, and the third layer will be described in detail below.

[0035] [First Layer] The first layer of the laminated nonwoven fabric of the present invention constitutes the outermost layer on one side of the laminated nonwoven fabric and is a nonwoven fabric containing 0.02% by mass or more and 0.50% by mass or less of an antistatic agent and a water repellent agent, respectively.

[0036] By configuring the outermost layer of the laminated nonwoven fabric with the first layer containing specific amounts of antistatic agent and water repellent agent, it is possible to improve the surface electrical resistivity, which is an index of the antistatic performance of the outermost layer of the laminated nonwoven fabric, and also improve the water pressure resistance of the laminated nonwoven fabric, resulting in excellent waterproofness.

[0037] Examples of the material of the fibers constituting the first layer include polyolefin resins (e.g., polyethylene, polypropylene, copolymers of ethylene and α-olefins, copolymers of propylene and α-olefins, etc.), styrene resins (e.g., polystyrene, acrylonitrile styrene resin, etc.), polyether resins (e.g., polyether ether ketone, polyacetal, modified polyphenylene ether, aromatic polyether ketone, etc.), polyester resins (e.g., polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polycarbonate, polyarylate, aromatic polyester, etc.), and the like. Examples of the resin include polyester resins, polyimide resins, polyamideimide resins, polyamide resins (e.g., aromatic polyamide resins, aromatic polyetheramide resins, nylon resins), urethane resins, epoxy resins, polysulfone resins (e.g., polysulfone, polyethersulfone), fluorine resins (e.g., polytetrafluoroethylene, polyvinylidene fluoride), cellulose resins, polybenzimidazole resins, and acrylic resins (e.g., polyacrylonitrile resins copolymerized with acrylic acid esters or methacrylic acid esters, and modacrylic resins copolymerized with acrylonitrile and vinyl chloride or vinylidene chloride).

[0038] Among these, polyolefin resins are preferred from the viewpoint of productivity and texture of the laminated nonwoven fabric, and among polyolefin resins, polypropylene is particularly preferred from the viewpoint of high mechanical strength.

[0039] Examples of nonwoven fabrics include spunbond nonwoven fabrics and meltblown nonwoven fabrics, and among these, spunbond nonwoven fabrics are preferred because of their high productivity, strength and breathability.

[0040] The first layer contains an antistatic agent in an amount of 0.02% by mass or more and 0.50% by mass or less.

[0041] The antistatic agent is a compound having an antistatic function, and examples thereof include cationic antistatic agents, amphoteric antistatic agents, and anionic antistatic agents. Examples of the cationic antistatic agents include quaternary ammonium salt compounds and acetate compounds of aliphatic amines, examples of amphoteric antistatic agents include betaine compounds, carboxymethylamine compounds, and imidazolium compounds, and examples of the anionic antistatic agents include sulfate ester compounds, sulfonic acid compounds, and phosphate ester compounds. Among these, the anionic antistatic agent is preferably an anionic antistatic agent, and more preferably a phosphate ester compound, in order to reduce the surface electrical resistance, which is an index of antistatic performance.

[0042] As a method for applying the antistatic agent, conventionally known techniques can be used within the scope of not impairing the effects of the present invention. For example, the first layer may be immersed in a treatment solution containing an antistatic agent, or the antistatic agent may be kneaded into the fibers constituting the first layer to perform an antistatic treatment on the fibers themselves. The antistatic treatment may also be performed by coating the first layer with a coating agent containing an antistatic agent. Among these, antistatic treatment by immersion treatment is preferred, as it is easy to reduce the surface electrical resistance, which is an antistatic performance, and has high productivity.

[0043] The antistatic agent has a structure having hydrophobic groups that are compatible with oil and hydrophilic groups that are compatible with water. The hydrophilic groups of the antistatic agent adsorb moisture in the air, and the inclusion of the antistatic agent is thought to reduce the surface electrical resistance value and exhibit excellent antistatic properties. However, at the same time, the antistatic agent tends to easily draw moisture into the laminated nonwoven fabric, promoting water permeation and reducing waterproof properties.

[0044] It is important that the amount of antistatic agent contained in the first layer is 0.02% by mass or more and 0.50% by mass or less. By setting the amount of antistatic agent contained in the first layer to 0.02% by mass or more, it is possible to reduce surface electrical resistance, which is an indicator of antistatic performance. Furthermore, while antistatic agents have the effect of adsorbing moisture in the air and reducing surface electrical resistance, they tend to easily draw moisture into the nonwoven fabric, thereby reducing water pressure resistance and waterproofing. Therefore, by setting the amount of antistatic agent contained in the first layer to 0.50% by mass or less, it is possible to suppress a decrease in water pressure resistance.

[0045] It is important that the first layer is a nonwoven fabric containing 0.02% by mass or more and 0.50% by mass or less of a water repellent agent.

[0046] The water repellent is not particularly limited as long as it can exhibit water repellency, but examples thereof include silicone-based water repellents, fluorine-based water repellents, wax-based water repellents, and hydrocarbon-based water repellents. Among these, silicone-based water repellents are preferred from the viewpoints of water repellency, durable water repellency, and water repellency when attached to fibers, and the texture of the textile product.

[0047] As a method for applying the water repellent, conventionally known techniques can be used to the extent that the effects of the present invention are not impaired. For example, the first layer may be immersed in a treatment solution containing a water repellent component, or the water repellent may be kneaded into the fibers constituting the first layer to impart water repellency to the fibers themselves. The water repellent treatment may also be performed by coating the first layer with a coating agent containing a water repellent. Among these, water repellent treatment by immersion is preferred because it has high productivity.

[0048] The water repellent agent has a lower liquid tension on the solid surface than water, making it easier to repel water, and it is believed that incorporating the agent into the fibers can prevent water from penetrating into the laminated nonwoven fabric. However, at the same time, it also tends to inhibit water adsorption onto the surface of the laminated nonwoven fabric, resulting in an increase in surface electrical resistance, which is an indicator of antistatic performance.

[0049] The amount of water repellent contained in the first layer is 0.02% by mass or more and 0.50% by mass or less. By setting it to 0.02% by mass or more, the hydrophobic effect of the water repellent agent prevents water on the surface of the first layer from penetrating into the laminated nonwoven fabric, improving the water pressure resistance of the laminated nonwoven fabric and providing excellent waterproofing. Furthermore, by setting the content of water repellent agent in the first layer to 0.50% by mass or less, it is possible to suppress the inhibition of water adsorption by the water repellent agent to the surface of the laminated nonwoven fabric and suppress an increase in surface electrical resistance, which is an indicator of antistatic performance.

[0050] The antistatic agent adsorbs moisture in the air onto the fiber surface, thereby exhibiting antistatic performance, but also increases the hydrophilicity of the fiber surface, reducing the water pressure resistance of the laminated nonwoven fabric and resulting in reduced waterproofing. Furthermore, the water repellent agent is hydrophobic, improving water pressure resistance, but also increasing the hydrophobicity of the fiber surface, inhibiting the adsorption of moisture in the air necessary for the antistatic performance to be exhibited and reducing the antistatic performance. By incorporating specific amounts of the antistatic agent and water repellent agent into the first layer, the laminated nonwoven fabric can achieve both excellent antistatic properties and waterproofing.

[0051] The basis weight of the first layer is not particularly limited as long as the strength is ensured, and is 5 to 40 g / m ２ The weight of the first layer is preferably 5 g / m ２ By setting the weight of the first layer to 40 g / m or more, the tensile strength of the laminated nonwoven fabric can be improved. ２ By setting the following, the laminated nonwoven fabric will have high flexibility and excellent texture.

[0052] The first layer can be given functions within the range that does not impair the effects of the present invention, for example, flame retardancy, antibacterial properties, and antifungal properties.

[0053] [Second Layer] The second layer of the laminated nonwoven fabric of the present invention does not contain an antistatic agent, or if it does contain an antistatic agent, the content of the antistatic agent is less than 0.02 mass % and is a nonwoven fabric having an average fiber diameter of 1.0 to 15.0 μm.

[0054] The material of the fibers constituting the second layer of the laminated nonwoven fabric of the present invention is the same as the material of the fibers constituting the first layer.

[0055] The second layer is a nonwoven fabric. The nonwoven fabric may be, for example, a spunbonded nonwoven fabric or a meltblown nonwoven fabric, but is preferably a meltblown nonwoven fabric made of fine fibers, from the viewpoint of excellent uniformity in basis weight and excellent uniformity in fiber distribution.

[0056] The average fiber diameter of the fibers constituting the second layer is 1.0 to 15.0 μm. By setting the average fiber diameter to 15 μm or less, the fibers constituting the nonwoven fabric become denser, and the mesh size of the second layer also becomes denser. In the laminated nonwoven fabric of the present invention, the second layer is disposed between the first and third layers, and the first layer contains a specific amount of water repellent, so that the water pressure resistance of the laminated nonwoven fabric of the present invention becomes extremely high, and the waterproofness of this laminated nonwoven fabric becomes extremely excellent. Furthermore, by setting the average fiber diameter to 1.0 μm or more, sufficient strength can be obtained to prevent poor handling. A range of 1 to 3 μm is more preferable.

[0057] The content of the antistatic agent in the second layer is less than 0.02% by mass. That is, the second layer does not contain an antistatic agent, or contains only a very small amount. The preferred type of antistatic agent is the same as the antistatic agent contained in the first layer. By making the amount of antistatic agent contained in the second layer less than 0.02% by mass, the penetration of moisture from the surface of the laminated nonwoven fabric into the second layer is suppressed, the water pressure resistance of the laminated nonwoven fabric is improved, and excellent waterproofing is achieved. The processing method for the antistatic agent is the same as the processing method for the antistatic agent in the first layer.

[0058] The weight of the second layer is 1 to 30 g / m ２ The weight of the second layer is preferably 1 g / m ２ By setting the weight of the second layer to 30 g / m or more, the water pressure resistance of the laminated nonwoven fabric is improved, and the waterproofness of the laminated nonwoven fabric is excellent. ２ By setting the following, the laminated nonwoven fabric will have excellent breathability.

[0059] The second layer can be given functions within the range that does not impair the effects of the present invention, for example, flame retardancy, antibacterial properties, and antifungal properties.

[0060] [Third Layer] The third layer of the laminated nonwoven fabric of the present invention constitutes the outermost layer on the other side of the laminated nonwoven fabric, and is a nonwoven fabric that does not contain an antistatic agent or, if it does contain an antistatic agent, the content of the antistatic agent is less than 0.02 mass %, is made of fibers made of a polyolefin resin, and has a tensile strength of 15 N or more.

[0061] The content of the antistatic agent in the third layer is less than 0.02% by mass. That is, the third layer does not contain an antistatic agent, or if it does contain an antistatic agent, it contains only a very small amount. The preferred type of antistatic agent is the same as the antistatic agent contained in the first layer. As described above, since the antistatic agent adsorbs moisture in the air, if the third layer contains a large amount of antistatic agent, the third layer will absorb moisture. Here, when a laminated nonwoven fabric is used such that the third layer directly contacts the skin, the moist third layer tends to become sticky with the skin, and the release properties of the laminated nonwoven fabric tend to deteriorate. Therefore, by setting the content of the antistatic agent in the third layer to less than 0.02% by mass, the third layer is prevented from absorbing moisture, so that the third layer does not become sticky when in contact with the skin, the release properties of the laminated nonwoven fabric are good, and protective clothing using this laminated nonwoven fabric with the third layer positioned on the wearer's side provides excellent comfort during work. The method for processing the antistatic agent is the same as the method for processing the antistatic agent in the first layer.

[0062] The fibers constituting the third layer are fibers made of an olefin resin. When the laminated nonwoven fabric is used in protective clothing, where the third layer is in direct contact with the skin, polyolefin resins such as polyethylene and polypropylene have low moisture absorption properties, which prevents the third layer from absorbing moisture. This allows the laminated nonwoven fabric to have excellent skin-releasing properties after sweating, and protective clothing in which this laminated nonwoven fabric is used with the third layer positioned on the wearer's side can provide high comfort during work. The third layer may also contain fibers other than polyolefin resin fibers. Examples of fibers other than polyolefin resin fibers include polyamide fibers and polyester fibers. The content of polyolefin resin fibers in the third layer is preferably 90% by mass of the entire third layer.

[0063] The third layer is a nonwoven fabric. Examples of the nonwoven fabric include spunbonded nonwoven fabric and meltblown nonwoven fabric. Among these, spunbonded nonwoven fabric is preferred because of its high productivity, strength, and breathability.

[0064] The third layer has a tensile strength of 15 N or more as measured in accordance with JIS L1096-2010. By making the third layer tensile strength 15 N or more, when water pressure is applied to the laminated nonwoven fabric in the direction from one side to the other, deformation of the laminated nonwoven fabric is suppressed, and rupture of the second layer, which has fine mesh and high fiber density and contributes to the high waterproofness of the laminated nonwoven fabric, is suppressed, resulting in improved water pressure resistance and excellent waterproofness of the laminated nonwoven fabric.

[0065] The basis weight of the third layer is not particularly limited as long as the tensile strength is ensured, and is preferably 5 to 40 g / m ２ The following is preferably used.

[0066] The third layer can be given functions within the range that does not impair the effects of the present invention, for example, flame retardancy, antibacterial properties, and antifungal properties.

[0067] The present invention will now be described in more detail with reference to examples.

[0068] [Measurement method] (1) Basis weight Based on JIS L1096-2010, two test pieces of 200 mm x 200 mm were taken, and the mass (g) of each was measured. ２ Mass (g / m ２ ) and calculate the average value.

[0069] (2) Water Pressure Resistance The water pressure resistance of the laminated nonwoven fabric was measured based on JIS L1092-2009 low water pressure method. Water pressure was applied to the test piece at a pressure increase rate of 60 cm / min, and the water pressure was measured when three water droplets appeared. The average value of three measurements was taken as the water pressure resistance.

[0070] (3) Wet frictional force (referred to as "wet frictional resistance force" in the table) The skin separation property was evaluated by wet frictional force, with the first layer of the laminated nonwoven fabric used as the measurement surface. Wet frictional force was measured according to JIS K 7125-1999 "Plastics - Films and sheets - Test method for coefficient of friction." A sample cut to 6 cm x 12 cm was placed on a horizontal stainless steel plate, and a 40 cm ２ After applying a load of 200 gf (1.96 N) to the area of ​​10 mm, the sample was pulled from one side at a pulling speed of 10 cm / min using a tensile tester, and the dynamic friction force was measured. Immediately before the measurement, water equivalent to 50% of the sample's weight was evenly applied to the entire sample.

[0071] (4) Air permeability The air permeability of the laminated nonwoven fabric was measured based on the Frazier method of JIS L1913-2010, and was defined as the amount of air passing through a test piece measuring 15 cm x 15 cm. The average value of the amount of air passing through obtained three times was defined as the air permeability.

[0072] (5) Surface Electrical Resistivity The surface electrical resistance of the antistatic dust protective fabric was measured using the first layer as the measurement surface, and the surface electrical resistance value obtained using a test piece measuring 12 cm x 12 cm was determined based on EN1149-1-2006.

[0073] (6) Content of Antistatic Agent or Water Repellent Agent (hereinafter sometimes referred to as "agent"). Layers other than the first layer of the laminated nonwoven fabric were removed using #1000 sandpaper. A 15 cm x 15 cm piece of the resulting first layer was cut out, and the weight of the resulting first layer was measured in grams to the fifth decimal place. The weighed first layer was placed in a beaker containing 100 ml of methanol and subjected to ultrasonic extraction for 10 minutes. The extract obtained by ultrasonic cleaning was dried at 40°C, concentrated to 1 ml, and filtered through a 0.45 μm PTFE disk filter. The resulting extract filtrate was diluted 10-fold and analyzed using a Shimadzu LC / MS / MS, LC20A. The antistatic agent and water repellent agent used were identified from the obtained results, and the areas of the peaks corresponding to the identified antistatic agent and water repellent agent were calculated. In order to calculate each drug adhesion rate, the same composition as the antistatic agent and water repellent agent identified from the first layer was newly prepared, and prepared 10 times diluted solution, 100 times diluted solution, and 1000 times diluted solution with methanol, respectively, and measured in the same manner as the extraction filtrate, and calculated the peak area corresponding to the identified antistatic agent and water repellent agent, and made a calibration curve of the identified amount of antistatic agent and amount of water repellent and the obtained peak area.Compared the peak area obtained from the solvent extract of the first layer with the calibration curve, calculated the amount of antistatic agent and amount of water repellent agent attached to the first layer, and divided by the weight of the first layer measured in advance, and rounded to the nearest tenth place to obtain the drug content (mass%) of the first layer.

[0074] For the second and third layers, all layers other than the second layer and all layers other than the third layer were removed, and the drug content (mass %) was calculated in the same manner as above.

[0075] (7) Average Fiber Diameter The laminated nonwoven fabric was cut perpendicular to its surface using a microtome. The cut surface of the laminated nonwoven fabric was photographed at 500x and 1000x magnifications using a Hitachi S-800 field emission scanning electron microscope (FE-SEM). These images were imported into the image analysis software attached to the device. For fibers with a fiber diameter of less than 10 μm, the fiber diameter was measured using an SEM image measured at 500x magnification. For fibers with a fiber diameter of 10 μm or more, the fiber diameter was measured using an SEM image measured at 1000x magnification. Specifically, 15 fibers constituting the second layer were randomly selected from the second layer shown in the SEM image, and the fiber diameters of these fibers were measured. The average of the 15 measurements was then used as the average fiber diameter of the fibers constituting the second layer. The fiber diameter of the fibers was calculated by reading the fiber diameter in units of μm to the second decimal place and rounding off the value to the nearest whole number.

[0076] (8) Tensile strength Based on Appendix J (strip method) of JIS L1096-2010, two test pieces of 300 mm × 50 mm were taken in the vertical and horizontal directions, respectively, and attached to the upper and lower clamps of a tensile tester. They were then pulled at a rate of 200 mm / min. The maximum value at which the test piece broke was measured, and the average value of three measurements was taken as the tensile strength.

[0077] The laminated nonwoven fabric was prepared as follows.

[0078] Example 1 An anionic antistatic agent ("ZELEC" (registered trademark) TY manufactured by STEPAN Co., Ltd.) and a silicone water repellent agent ("Drypon" (registered trademark) 600E manufactured by NICCA Chemical Co., Ltd.) were mixed with pure water according to the chemical formulation A shown in Table 1, and a fiber having an average fiber diameter of 25.0 μm and a density of 20 g / m was obtained. ２ A polypropylene spunbond nonwoven fabric A having a tensile strength of 25 N was subjected to mangling. The mangling-treated spunbond nonwoven fabric was dried in a pin tenter at 135°C for 1 minute to obtain a spunbond nonwoven fabric A1, which was used as the first layer. A polypropylene spunbond nonwoven fabric A2 having an average fiber diameter of 1.6 µm and a basis weight of 15 g / m was used as the second layer. ２ The third layer was made of a polypropylene melt-blown nonwoven fabric A having an average fiber diameter of 25.0 μm and a weight of 20 g / m. ２The first layer, second layer, and third layer were laminated in this order, and then embossed at a temperature of 120°C and a pressure of 60 kg / m using an embossing device. ２ The layer structure of Example 1 and the surface electrical resistance, water pressure resistance, frictional force in a wet state, and breathability of the laminated nonwoven fabric obtained are shown in Table 2.

[0079] Examples 2 to 5 Spunbond nonwoven fabrics A2 to A5 were obtained using spunbond nonwoven fabric A, an anionic antistatic agent, and a silicone water repellent agent in the same manner as in Example 1, except that the drug formulation was changed to formulations B, C, D, or E. Furthermore, except that spunbond nonwoven fabric A1 was replaced with spunbond nonwoven fabrics A2 to A5, the laminated nonwoven fabrics of Examples 2 to 5 were obtained in the same manner as in Example 1. The layer structures of the obtained Examples 2 to 5 and the surface electrical resistance, water pressure resistance, frictional force in a wet state, and breathability of the laminated nonwoven fabrics are shown in Table 2.

[0080] Example 6 An anionic antistatic agent was mixed with pure water in accordance with formulation I shown in Table 1, and a spunbonded woven fabric was prepared with an average fiber diameter of 1.6 μm and a basis weight of 15 g / m ２ Polypropylene melt-blown nonwoven fabric A was subjected to mangling. The mangled melt-blown nonwoven fabric was dried in a pin tenter at 135°C for 1 minute to obtain melt-blown nonwoven fabric A1. Furthermore, a laminated nonwoven fabric of Example 6 was obtained in the same manner as in Example 1, except that melt-blown nonwoven fabric A1 was used as the second layer. The layer structure of Example 6 and the surface electrical resistance, water pressure resistance, frictional force in a wet state, and breathability of the resulting laminated nonwoven fabric are shown in Table 2.

[0081] Example 7: Average fiber diameter 12.2 μm, basis weight 15 g / m ２ A laminated nonwoven fabric of Example 7 was obtained in the same manner as in Example 1, except that polypropylene melt-blown nonwoven fabric B was used as the second layer. The layer structure of Example 7 obtained and the surface electrical resistance, water pressure resistance, frictional force in a wet state, and breathability of the laminated nonwoven fabric are shown in Table 2.

[0082] Example 8 An anionic antistatic agent was mixed with pure water in accordance with formulation I shown in Table 1, and a fiber having an average fiber diameter of 25.0 μm and a weight of 20 g / m ２Polypropylene spunbond nonwoven fabric A having a tensile strength of 25 N was subjected to mangling. The mangled polypropylene spunbond nonwoven fabric was dried at 135°C for 1 minute in a pin tenter to obtain spunbond nonwoven fabric A9. Furthermore, a laminated nonwoven fabric of Example 8 was obtained in the same manner as in Example 1, except that spunbond nonwoven fabric A9 was used as the third layer. The layer structure of Example 8 obtained and the surface electrical resistance, water pressure resistance, frictional force in a wet state, and breathability of the laminated nonwoven fabric are shown in Table 2.

[0083] Example 9: Average fiber diameter 35.0 μm, 20 g / m ２ A laminated nonwoven fabric of Example 9 was obtained in the same manner as in Example 1, except that polypropylene spunbond nonwoven fabric B having a tensile strength of 16 N was used as the third layer. The layer structure of Example 9 and the surface electrical resistance, water pressure resistance, frictional force in a wet state, and breathability of the resulting laminated nonwoven fabric are shown in Table 3.

[0084] Examples 10 and 11 Spunbond nonwoven fabrics A6 and A7 were obtained using spunbond nonwoven fabric A, a cationic antistatic agent (Osmoline (registered trademark) DA-50, manufactured by Sanyo Chemical Industries, Ltd.), and a fluorine-based water repellent agent (Unidyne (registered trademark) XF-5007, manufactured by Daikin Industries, Ltd.) in the same manner as in Example 1, except that the drug formulations were changed to formulations F and G. Furthermore, laminated nonwoven fabrics of Examples 10 and 11 were obtained in the same manner as in Example 1, except that spunbond nonwoven fabric A1 was replaced with spunbond nonwoven fabrics A6 to A7. The layer structures of the obtained laminated nonwoven fabrics of Examples 10 and 11 and the surface electrical resistance, water pressure resistance, frictional force in a wet state, and breathability are shown in Table 3.

[0085] Examples 12 and 13 Spunbond nonwoven fabrics A11 and A12 were obtained using spunbond nonwoven fabric A, an anionic antistatic agent, and a silicone water repellent agent in the same manner as in Example 1, except that the drug formulations were changed to formulations K and L. Furthermore, except that spunbond nonwoven fabric A1 was changed to spunbond nonwoven fabrics A11 and A12, respectively, the laminated nonwoven fabrics of Examples 12 and 13 were obtained in the same manner as in Example 1. The layer structures of the obtained Examples 12 and 13 and the surface electrical resistance, water pressure resistance, frictional force in a wet state, and breathability of the laminated nonwoven fabrics are shown in Table 3.

[0086] Comparative Example 1 Spunbond nonwoven fabric A8 was obtained using spunbond nonwoven fabric A, an anionic antistatic agent, and a silicone water repellent agent in the same manner as in Example 1, except that the drug formulation was changed to Formulation H. Furthermore, except that spunbond nonwoven fabric A8 was used instead of spunbond nonwoven fabric A8, a laminated nonwoven fabric of Comparative Example 1 was obtained in the same manner as in Example 1. The layer structure of the obtained Comparative Example 1 and the surface electrical resistance, water pressure resistance, frictional force when wet, and breathability of the laminated nonwoven fabric are shown in Table 4.

[0087] Comparative Example 2: The first layer was made of a woven fabric having an average fiber diameter of 25.0 μm and a weight per square meter (g / m). ２ The second layer is made of a polypropylene spunbond nonwoven fabric A having a tensile strength of 25 N and an average fiber diameter of 1.6 μm and a basis weight of 15 g / m. ２ The third layer was made of a polypropylene melt-blown nonwoven fabric A having an average fiber diameter of 25.0 μm and a weight of 20 g / m. ２ The first layer, second layer, and third layer were laminated in this order, and then embossed at a temperature of 120°C and a pressure of 60 kg / m using an embossing device. ２ The layer structure of Comparative Example 2 and the surface electrical resistance, water pressure resistance, frictional force in a wet state, and breathability of the laminated nonwoven fabric are shown in Table 4.

[0088] Comparative Example 3 Melt-blown nonwoven fabric A2 was obtained using melt-blown nonwoven fabric A and an anionic antistatic agent in the same manner as in Example 6, except that drug formulation I in Example 6 was replaced with formulation J. Furthermore, a laminated nonwoven fabric of Comparative Example 3 was obtained in the same manner as in Example 6, except that melt-blown nonwoven fabric A2 was used instead of melt-blown nonwoven fabric A1. The layer structure of the obtained Comparative Example 4 and the surface electrical resistance, water pressure resistance, frictional force when wet, and breathability of the laminated nonwoven fabric are shown in Table 4.

[0089] <Comparative Example 4> Average fiber diameter 21.2 μm, basis weight 15 g / m ２ A laminated nonwoven fabric of Comparative Example 4 was obtained in the same manner as in Example 7, except that polypropylene melt-blown nonwoven fabric C was used as the second layer. The layer structure of the obtained laminated nonwoven fabric of Comparative Example 4 and the surface electrical resistance, water pressure resistance, and frictional force in a wet state are shown in Table 4.

[0090] Comparative Example 5 Spunbond nonwoven fabric A10 was obtained using spunbond nonwoven fabric A and an anionic antistatic agent in the same manner as in Example 8, except that drug formulation I was replaced with formulation J. Furthermore, a laminated nonwoven fabric of Comparative Example 5 was obtained in the same manner as in Example 6, except that spunbond nonwoven fabric A10 was used instead of spunbond nonwoven fabric A9. The layer structure of the obtained Comparative Example 5 and the surface electrical resistance, water pressure resistance, frictional force in a wet state, and breathability of the laminated nonwoven fabric are shown in Table 4.

[0091] <Comparative Example 6> Average fiber diameter 14.0 μm, 20 g / m ２ The laminated nonwoven fabric of Comparative Example 6 was obtained in the same manner as in Example 9, except that polypropylene spunbond nonwoven fabric C having a tensile strength of 12 N was used as the third layer. The layer structure of the obtained Comparative Example 6 and the surface electrical resistance, water pressure resistance, wet frictional force, and air permeability of the laminated nonwoven fabric are shown in Table 4. <Comparative Examples 7 to 9> Spunbond nonwoven fabrics A13, A14, and A15 were obtained using spunbond nonwoven fabric A, an anionic antistatic agent, and a silicone water repellent in the same manner as in Example 1, except that the drug formulation was changed to formulations M, N, and O. Furthermore, the laminated nonwoven fabrics of Comparative Examples 7 to 9 were obtained in the same manner as in Example 1, except that spunbond nonwoven fabric A was changed to spunbond nonwoven fabrics A13, A14, and A15. The layer structure of the obtained Comparative Examples 7 to 9 and the surface electrical resistance, water pressure resistance, wet frictional force, and air permeability of the laminated nonwoven fabrics are shown in Table 4.

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[0093]

[0094]

[0095]

[0096] According to the present invention, it is possible to provide a laminated nonwoven fabric and protective clothing that have excellent antistatic properties, waterproofness, and breathability, and further have good skin-relaxing properties.

Claims

1. A laminated nonwoven fabric having a first layer, a second layer, and a third layer in this order, the first layer is a nonwoven fabric that constitutes the outermost layer on one surface of the laminated nonwoven fabric, the first layer contains an antistatic agent and a water repellent agent; the content of the antistatic agent is 0.02% by mass or more and 0.50% by mass or less with respect to the entire first layer; the content of the water repellent agent is 0.02% by mass or more and 0.50% by mass or less with respect to the entire first layer, the second layer is a nonwoven fabric; the average fiber diameter of the fibers constituting the second layer is 1.0 to 15.0 μm; The second layer does not contain an antistatic agent, or if it does contain an antistatic agent, the content of the antistatic agent is less than 0.02% by mass based on the total mass of the second layer; the third layer is a nonwoven fabric that constitutes the outermost layer on the other surface of the laminated nonwoven fabric, the fibers constituting the third layer are fibers made of an olefin-based resin, The third layer does not contain an antistatic agent, or if it does contain an antistatic agent, the content of the antistatic agent is less than 0.02% by mass based on the total mass of the third layer; the third layer has a tensile strength of 15 N or more as measured in accordance with JIS L1096-2010; The laminated nonwoven fabric has a water pressure resistance of 1000 mmH 2 O or more as measured in accordance with JIS L1092-2009.

2. The basis weight of the second layer is 1 to 30 g / m ２ The laminated nonwoven fabric according to claim 1,

3. The surface electrical resistance value of the one surface measured in accordance with EN1149-1-2006 is 2.5 × 10 ９ The laminated nonwoven fabric according to claim 1 or 2, having a modulus of elasticity of Ω or less.

4. The air permeability measured based on JIS L1913-2010 is 5 cm ３ / cm ２ The laminated nonwoven fabric according to claim 1 or 2, wherein the elongation is 1 / sec or more.

5. 3. The laminated nonwoven fabric according to claim 1, wherein the other surface has a wet friction force of 0.7 N or less as measured in accordance with JIS K7125-1999.

6. A protective suit using the laminated nonwoven fabric according to claim 1 or 2, The first layer is disposed to form an outer surface of the protective garment.

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