Nonwoven fabric sheet and gas filter

Abstract

To enable achievement of excellent air permeability on a nonwoven fabric sheet in which microcapsules are supported on a nonwoven fabric.SOLUTION: A nonwoven fabric sheet 10A comprises: a sheet body including a first nonwoven fabric 11A; and a plurality of microcapsules supported on the first nonwoven fabric 11A. A plurality of belt-like patterns aligned so as to be spaced away from each other in a width direction are formed on a part P1, which supports the plurality of microcapsules, of the first nonwoven fabric 11A. Width of each of the plurality of belt-like patterns is 1 mm or more and a distance between adjacent belt-like patterns is 1 mm or more.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a nonwoven sheet and a gas filter.

Background Art

[0002] In recent years, products have been developed in which agents having various desirable effects such as antiseptic, disinfectant, antibacterial, antiviral, deodorant, and fragrance are microencapsulated and supported on nonwoven fabrics. Depending on the design of the microcapsules, such products can adjust the period and timing of drug release, and can be used, for example, for the preservation of crops and foods and for sanitary products such as masks and diapers. For example, Patent Document 1 describes a composite material for preserving crops in which essential oils having insecticidal, fungicidal, static fungicidal, bactericidal, static bactericidal, or spoilage-delaying effects are microencapsulated and supported on a nonwoven fabric.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present invention is to achieve excellent air permeability in a nonwoven sheet in which microcapsules are supported on a nonwoven fabric.

Means for Solving the Problems

[0005] According to one aspect of the present invention, there is provided a sheet body including a first nonwoven fabric, and a plurality of microcapsules supported on the first nonwoven fabric, wherein a portion of the first nonwoven fabric on which the plurality of microcapsules are supported forms a plurality of strip-shaped patterns arranged at intervals from each other in the width direction, and each of the plurality of strip-shaped patterns has a width of 1 mm or more and a distance between adjacent ones is 1 mm or more.

[0006] According to another aspect of the present invention, there is provided a nonwoven fabric sheet according to the above aspect, wherein each of the plurality of strip patterns has a width of 300 mm or less and a distance between adjacent ones of 300 mm or less.

[0007] According to still another aspect of the present invention, there is provided a nonwoven fabric sheet according to any one of the above aspects, wherein the total area of the plurality of strip patterns occupies a ratio of 5 to 90% of the area of the first nonwoven fabric.

[0008] According to still another aspect of the present invention, there is provided a nonwoven fabric sheet according to any one of the above aspects, wherein the number of the plurality of strip patterns per unit width of the first nonwoven fabric is in the range of 2 to 500 pieces / m.

[0009] According to still another aspect of the present invention, there is provided a nonwoven fabric sheet according to any one of the above aspects, wherein the mass per unit area of the plurality of microcapsules is in the range of 0.005 to 19 g / m 2 of the first nonwoven fabric.

[0010] According to still another aspect of the present invention, there is provided a nonwoven fabric sheet according to any one of the above aspects, wherein the basis weight of the sheet body is in the range of 1 to 1000 g / m 2 of the first nonwoven fabric.

[0011] According to still another aspect of the present invention, there is provided a nonwoven fabric sheet according to any one of the above aspects, wherein the sheet body further includes a second nonwoven fabric laminated with the first nonwoven fabric.

[0012] According to still another aspect of the present invention, there is provided a nonwoven fabric sheet according to the above aspect, wherein the second nonwoven fabric does not carry microcapsules.

[0013] According to still another aspect of the present invention, there is provided a nonwoven fabric sheet according to the above aspect, wherein the sheet body further includes a third nonwoven fabric laminated with the first nonwoven fabric and the second nonwoven fabric.

[0014] According to still another aspect of the present invention, there is provided a nonwoven fabric sheet according to the above aspect in which the second nonwoven fabric and the third nonwoven fabric do not carry microcapsules.

[0015] According to still another aspect of the present invention, there is provided a nonwoven fabric sheet according to any one of the above aspects in which the third nonwoven fabric faces the second nonwoven fabric with the first nonwoven fabric interposed therebetween.

[0016] According to still another aspect of the present invention, there is provided a gas filter including a nonwoven fabric sheet according to any one of the above aspects.

Advantages of the Invention

[0017] According to the present invention, it is possible to achieve excellent air permeability in a nonwoven fabric sheet in which microcapsules are carried on the nonwoven fabric.

Brief Description of the Drawings

[0018]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Modes for Carrying Out the Invention

[0019] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The embodiments described below are more specific forms of any of the above aspects. The matters described below can be incorporated into each of the above aspects alone or in combination.

[0020] Also, the embodiments shown below illustrate configurations for embodying the technical idea of the present invention, and the technical idea of the present invention is not limited by the materials, shapes, structures, etc. of the following constituent members. Various changes can be made to the technical idea of the present invention within the technical scope defined by the claims described in the claims.

[0021] Also, the drawings are schematic, and the relationship between dimensions in one direction and dimensions in another direction, and the relationship between the dimensions of one member and the dimensions of other members, etc. may be different from the actual ones. For example, in the following embodiments, for ease of understanding, omissions and simplifications of components and the like are appropriately made. Also, the arrangement, size, and shape of the components in the drawings may not match the actual arrangement, size, shape, and arrangement, etc. for ease of understanding. Furthermore, unless otherwise noted, each component may be provided singly or in plural. That is, the present invention is not necessarily limited to the arrangement positions, sizes, shapes, and numbers shown in the drawings.

[0022] Note that components that exhibit the same or similar functions are given the same reference numerals throughout all the drawings, and duplicate explanations are omitted.

[0023] <1>First Embodiment <1.1>Nonwoven Sheet and Gas Filter FIG. 1 is a top view of a gas filter according to a first embodiment of the present invention. FIG. 2 is a cross-sectional view taken along line II-II of the gas filter shown in FIG. 1. FIG. 3 is an enlarged view showing the coating portion of the gas filter shown in FIGS. 1 and 2.

[0024] The gas filter 1A shown in FIGS. 1 and 2 allows a gas such as air to pass through and removes at least a part of the solids, liquids, and gas components contained in the gas that are entrained with the gas. The gas filter 1A can be used, for example, in an air conditioner, a heating device, a cooling device, a dehumidifying device, a humidifying device, a dust collecting device, an air cleaning device, or a mask.

[0025] The gas filter 1A includes a nonwoven fabric sheet 10A. Although the terms "sheet" and "film" may sometimes be distinguished from each other based on thickness, here, these terms are not distinguished by thickness and each can be handled alone and means a thin layer having flexibility.

[0026] The nonwoven fabric sheet 10A is rectangular here. The nonwoven fabric sheet 10A may have other shapes such as a square shape, an elliptical shape, and an oval shape.

[0027] The nonwoven fabric sheet 10A includes a sheet body including a first nonwoven fabric 11A and microcapsules 12 shown in FIG. 3.

[0028] The sheet body is the main body of the gas filter 1A and has air permeability in its thickness direction. The sheet body, for example, plays a role of capturing at least one of the solids and liquids entrained with the gas when the gas passes through the gas filter 1A. The sheet body also plays a role as a support for supporting the microcapsules 12 shown in FIG. 3.

[0029] The basis weight of the sheet body, that is, the mass per unit area of the sheet body, is preferably 1 g / m 2 or more, more preferably 5 g / m 2 or more, and even more preferably 15 g / m 2 or more. Increasing the basis weight of the sheet body makes it easier to generate gas turbulence in the nonwoven fabric sheet 10A, and therefore, the frequency of contact between the gas and the microcapsules 12 increases.

[0030] The basis weight of the sheet body is preferably 1000 g / m 2 or less, more preferably 500 g / m 2 or less, and even more preferably 100 g / m 2 or less. Increasing the basis weight of the sheet body may reduce the air permeability of the non-woven fabric sheet 10A.

[0031] Here, the sheet body is composed of the first non-woven fabric 11A shown in FIGS. 1 and 2. As shown in FIG. 3, the first non-woven fabric 11A is formed by intertwining, fusing, or adhering a large number of fibers 110 to each other without weaving or knitting, and is integrally formed into a thin layer. The first non-woven fabric 11A has air permeability in its thickness direction. Here, the basis weight of the first non-woven fabric 11A is equal to that of the sheet body.

[0032] The microcapsules 12 are carried on the first non-woven fabric 11A. At least a part of the microcapsules 12 is located between both main surfaces of the first non-woven fabric 11A. These microcapsules 12 are located in a space surrounded by a plurality of fibers 110. The microcapsules 12 may further include those located on one main surface of the first non-woven fabric 11A, or may further include those located on one main surface of the first non-woven fabric 11A and those located on the other main surface of the first non-woven fabric 11A.

[0033] The microcapsules 12 include a core material and a shell material. The core material includes a functional material that imparts a new function to the sheet body or enhances the function that the sheet body has. The functional material may be any material as long as it plays the above role.

[0034] According to an example, the functional material is a substance that exhibits one or more of anti-corrosion, disinfection, repellency, antibacterial, antiviral, deodorization, and fragrance. Such a substance is, for example, an essential oil that exhibits one or more of the above effects. The functional material may be a mixture containing two or more of the above-mentioned substances.

[0035] As the essential oil, for example, one or more selected from the group consisting of angelica oil, anise oil, sweet flag oil, bay oil, bergamot oil, bois de rose oil, calendula oil, cananga oil, clove oil, cardamom oil, cedar oil, cedarwood oil, hinoki oil, chamomile oil, cinnamon oil, citronella oil, sassafras oil, clove oil, copaiba balsam oil, coriander oil, cumin oil, dill oil, eucalyptus oil, perilla oil, garlic oil, geranium oil, ginger oil, grapefruit oil, guaiacwood oil, hiba oil, camphor oil, iris oil, peppermint oil, fennel oil, jasmine oil, lavender oil, laurel leaf oil, lemon oil, lemongrass oil, lime oil, linaloe oil, roman chamomile oil, mandarin oil, horseradish oil, neroli oil, onion oil, orange oil, oregano oil, palmarosa oil, orris root oil, patchouli oil, almond oil, pennyroyal oil, pepper oil, peppermint oil, perilla oil, peru balsam oil, ptychopetalum oil, pine needle oil, rose oil, rosemary oil, camphor oil, spearmint oil, star anise oil, magnolia oil, tea tree oil, tea oil, thyme oil, tolu balsam oil, tuberose oil, turmeric oil, vetiver oil, peppermint oil, white microthyme oil, wintergreen oil, and derivatives thereof can be used.

[0036] The above derivatives include, for example, allyl isothiocyanate, alpha terpineol, amyl cinnamic aldehyde, anisaldehyde, benzyl alcohol, benzyl acetate, cinnamic aldehyde, cinnamic alcohol, carvacrol, carveol, carvon, citral, citronellal, citronellol, eucalyptol (cineole), eugenol, iso-eugenol, galaxolide, geraniol, guaiacol, hexanal, ionone, d-limonene, menthol, methyl anthranilate, methyl ionone, methyl salicylate, alpha-phellandrene, pennyroyal oil, perillaldehyde, 1-phenylethyl alcohol, 2-phenylethyl alcohol, 1-phenylethyl propionate, 2-phenylethyl propionate, piperonal, piperonyl acetate, piperonyl alcohol, D-pulegone, terpinene-4-ol, terpinyl acetate, 4-tert-butylcyclohexyl acetate, thymol, trans-anethole, vanillin, and ethyl vanillin.

[0037] These can exhibit one or more of insecticidal, insect repellent, fungicidal, antifungal, bactericidal, antibacterial, and spoilage delaying effects.

[0038] According to another example, the functional material is an agent that exhibits an antiviral (virus inactivating) effect. According to still another example, the functional material is a fragrance. The functional material may be a mixture containing two or more of the above-described substances.

[0039] The core material containing the above functional material can further contain one or more of a solvent, a dispersion medium, and an additive. For example, the core material can further contain a non-volatile oil. The non-volatile oil is, for example, one or more selected from the group consisting of cottonseed oil, neem oil, castor oil, pyrethrum oil, sesame oil, and derivatives thereof. Also, the core material may further contain a preservative.

[0040] According to still another example, the functional material is a phase transition material. The phase transition material is, for example, a material that undergoes a reversible phase transition between a solid phase and a liquid phase.

[0041] Such a phase transition material absorbs heat during the phase transition from the solid phase to the liquid phase. When this phase transition temperature is slightly lower than the surface temperature of the living body, for example, when the phase transition temperature is in the range of 20 to 35 ° C, the microcapsules containing this phase transition material can provide a cooling or warming effect. As such a phase transition material, hydrocarbon compounds such as paraffin and wax are preferably used.

[0042] The shell material encapsulates the core material. When the functional material exerts its function inside the shell material, for example, when the core material is composed of a phase transition material, the shell material prevents all of the functional material, preferably the material constituting the core material, from being released to the outside of the shell material. When the functional material exerts its function by being released to the outside of the shell material, the shell material allows the functional material to permeate at a low rate, or can be at least partially destroyed by external stimuli such as pressurization and / or heating.

[0043] The shell material is composed of a polymer such as a melamine resin, an acrylic resin, and a urethane resin. The shell material may have a single-layer structure or a multilayer structure.

[0044] The average particle diameter of the microcapsules 12 is preferably in the range of 0.1 to 100 μm, and more preferably in the range of 1 to 50 μm. Here, the average particle diameter is a value obtained by the laser diffraction method.

[0045] When the average particle diameter is reduced, it becomes difficult to increase the ratio of the mass of the core material to the mass of the microcapsules 12. When the average particle diameter is increased, the dispersion and coating processes become difficult.

[0046] The non-woven fabric sheet 10A may contain only one kind of microcapsules 12 or may contain a plurality of kinds.

[0047] The non-woven fabric sheet 10A can further contain a binder resin. The binder resin serves, for example, to fix the microcapsules 12 to the first non-woven fabric 11A or to make it difficult for the microcapsules 12 to fall off from the first non-woven fabric 11A.

[0048] Examples of the binder resin include urethane resin, self-crosslinking acrylic resin, methacrylic resin, silicone resin, glyoxal resin, polyester resin, vinyl acetate resin, vinylidene chloride resin, butadiene resin, melamine resin, epoxy resin, acrylic-silicone copolymer resin, styrene-butadiene copolymer resin (SBR), ethylene-vinyl acetate copolymer resin (EVA), isobutylene maleic anhydride copolymer resin, ethylene-styrene-acrylate-methacrylate copolymer resin, polyvinyl alcohol resin (PVA), and combinations of two or more of these.

[0049] In the non-woven fabric sheet 10A, as shown in FIGS. 1 and 2, the first non-woven fabric 11A includes a first portion P1 that carries the microcapsules 12 and a second portion P2 that does not carry the microcapsules 12.

[0050] The first portion P1 forms a plurality of strip-shaped patterns arranged spaced apart from each other in the width direction. The second portion P2 forms one or more patterns adjacent to each other in the width direction with respect to the strip-shaped patterns formed by the first portion P1. That is, the strip-shaped patterns formed by the first portion P1 and the patterns formed by the second portion P2 are arranged alternately in their width direction, forming a striped arrangement.

[0051] The first portion P1 and the second portion P2 have different air permeabilities due to the presence or absence of the microcapsules 12. Specifically, the second portion P2 has higher air permeability than the first portion P1. Thus, since the non-woven fabric sheet 10A includes the second portion P2, excellent air permeability can be achieved.

[0052] In addition, the difference in air permeability between the first part P1 and the second part P2 can cause turbulent flow, for example, vortex-like turbulent flow, in the strip pattern formed by the first part P1 and the downstream region thereof when gas is passed through the nonwoven fabric sheet 10A. This turbulent flow can increase the frequency of contact between the gas and the microcapsules 12. Therefore, even though the nonwoven fabric sheet 10A includes the second part P2 that does not carry the microcapsules 12, the gas and the microcapsules 12 can be brought into contact with each other at a high frequency. Accordingly, when the above-described turbulent flow occurs, the effect expected of the microcapsules 12 is not significantly impaired by the second part P2 that does not carry the microcapsules 12.

[0053] In the nonwoven fabric sheet 10A, the width W1 of each strip pattern formed by the first part P1 is 1 mm or more. This width W1 is preferably 3 mm or more, and more preferably 5 mm or more.

[0054] Also, the distance D between adjacent strip patterns formed by the first part P1 is 1 mm or more. This distance D is preferably 3 mm or more, and more preferably 5 mm or more.

[0055] If the width W1 and the distance D are too small, the gas flow becomes almost equal to the case where the microcapsules 12 are uniformly distributed over the entire first nonwoven fabric 11A. Therefore, in this case, almost no turbulent flow occurs due to the difference in air permeability between the first part P1 and the second part P2. Also, if the width W1 is reduced, the shape accuracy or dimensional accuracy of the strip pattern formed by the first part P1 may decrease.

[0056] The width W1 is preferably 300 mm or less, more preferably 185 mm or less, and even more preferably 25 mm or less. If the width W1 is increased, the distance from the pattern formed by the second part P2 in the central region in the width direction of the strip pattern formed by the first part P1 becomes larger. Therefore, in this region, the effect of increasing the contact frequency between the gas and the microcapsules 12 by turbulent flow becomes smaller.

[0057] The distance D is preferably 300 mm or less, more preferably 50 mm or less, and even more preferably 15 mm or less. When the distance D is increased, the contribution of the central region in the width direction of the pattern formed by the second portion P2 to the generation of turbulent flow decreases.

[0058] The total area of the strip-shaped patterns formed by the first portion P1 preferably occupies a ratio in the range of 5 to 95% of the area of the first nonwoven fabric 11A, more preferably in the range of 20 to 80%, and even more preferably in the range of 40 to 60%.

[0059] When this ratio is decreased, it may be necessary to increase the amount of microcapsules 12 per unit area of the first portion P1 in order to exert the expected effect on the microcapsules 12. When this ratio is increased, the air permeability of the nonwoven fabric sheet 10A may decrease. Note that this ratio is equal to the ratio of the sum of the widths W1 of the plurality of strip-shaped patterns formed by the first portion P1 to the width W of the nonwoven fabric sheet 10A or the first nonwoven fabric 11A.

[0060] The number of strip-shaped patterns formed by the first portion P1 per unit width of the first nonwoven fabric 11A is preferably in the range of 2 to 500 pieces / m, more preferably in the range of 4 to 100 pieces / m, and even more preferably in the range of 10 to 50 pieces / m. When the width W1 and the distance D are decreased, this value increases.

[0061] The mass of the microcapsules 12 per unit area of the first nonwoven fabric 11A is preferably in the range of 0.005 to 19 g / m 2 more preferably in the range of 0.025 to 9.5 g / m 2 and even more preferably in the range of 0.05 to 5.7 g / m 2

[0062] Also, the mass of the microcapsules 12 per unit area of the first portion P1 is preferably in the range of 0.1 to 20 g / m 2 more preferably in the range of 0.5 to 10 g / m 2 ​It is more preferably within the range of, and 1 to 6 g / m 2 It is even more preferably within the range of.

[0063] If these values are extremely small, the gas flow will be almost equal to the case where the microcapsules 12 are uniformly distributed over the entire first nonwoven fabric 11A. If these values are increased, there is a possibility that the air permeability will decrease or the effect of increasing the frequency of contact between the gas and the microcapsules 12 will be reduced.

[0064] <1.2> Method for manufacturing a nonwoven fabric sheet and a gas filter The nonwoven fabric sheet 10A can be manufactured, for example, by applying a microcapsule dispersion liquid to the first nonwoven fabric 11A and drying it.

[0065] As the first nonwoven fabric 11A, according to one example, those having a width within the range of 1 to 3000 mm are prepared, and according to another example, those having a width within the range of 10 to 2500 mm are prepared.

[0066] The microcapsule dispersion liquid contains the above-mentioned microcapsules 12 and a dispersion medium.

[0067] The ratio of the mass of the microcapsules 12 to the mass of the microcapsule dispersion liquid is preferably within the range of 0.9 to 49.9%, and more preferably within the range of 1 to 39%. If this ratio is decreased, the amount of microcapsules 12 that can be supported on the first nonwoven fabric 11A may decrease. If this ratio is increased, the supply of the microcapsule dispersion liquid to the first nonwoven fabric 11A may become unstable when the microcapsule dispersion liquid is applied.

[0068] The dispersion medium is, for example, an aqueous solvent. The aqueous solvent may be water or a mixture of water and an organic solvent such as alcohol. The dispersion medium may also be an organic solvent.

[0069] The microcapsule dispersion can further contain the above binder resin. The ratio of the mass of the binder resin to the mass of the microcapsule dispersion is preferably in the range of 0.1 to 49.1%, and more preferably in the range of 0.2 to 30%. The binder resin can be omitted, but if this ratio is decreased, the adhesion between the microcapsules 12 and the first nonwoven fabric 11A may become insufficient. If this ratio is increased, the air permeability of the nonwoven fabric sheet 10A may decrease.

[0070] The microcapsule dispersion can further contain additives. For example, the microcapsule dispersion may further contain a dispersant.

[0071] The solid content of the microcapsule dispersion is preferably in the range of 1 to 50% by mass, and more preferably in the range of 2 to 40% by mass. If the solid content is decreased, the amount of microcapsules 12 that can be supported on the first nonwoven fabric 11A decreases, and sufficient functions may not be obtained. If the solid content is increased, the supply of the microcapsule dispersion may become unstable in the coating process.

[0072] For coating the microcapsule dispersion on the first nonwoven fabric 11A, known coating methods such as an inkjet method, a gravure coating method, a slit coating method, a bar coating method, a flexo coating method, a die coating method, and a roll coating method are used. In order to reduce the breakage of the microcapsules 12 during the coating process, the slit coating method or the die coating method is preferred. A single coating method or a plurality of coating methods may be used for this coating.

[0073] The first nonwoven fabric 11A coated with the microcapsule dispersion is dried, for example, by heating or by a combination of heating and blowing.

[0074] In this way, a nonwoven fabric sheet 10A is obtained as the gas filter 1A. The gas filter 1A may be obtained by cutting the nonwoven fabric sheet 10A obtained as described above into appropriate dimensions.

[0075] For the production of the nonwoven fabric sheet 10A, for example, a roll-to-roll method can be used.

[0076] FIG. 4 is a perspective view schematically showing an example of a production apparatus that can be used for the production of the gas filter shown in FIGS. 1 and 2.

[0077] The production apparatus 300 shown in FIG. 4 is a roll-to-roll die coater. As will be described later, the production apparatus 300 uses a plurality of slot die heads 330 to apply a microcapsule dispersion liquid to the first nonwoven fabric 11A.

[0078] The production apparatus 300 includes an unwinding device, a winding device, a plurality of guide rolls, a pair of liquid supply devices 310, a pair of liquid supply pipes 320, a pair of slot die heads 330, and a drying device.

[0079] The unwinding device is provided with a first nonwoven fabric 11A wound in a roll shape. The unwinding device includes a support portion, for example, a rotating shaft, that rotatably supports the roll made of the first nonwoven fabric 11A. The unwinding device enables the unwinding of the first nonwoven fabric 11A.

[0080] The guide roll sequentially guides the first nonwoven fabric 11A unwound from the unwinding device to the slot die head 330, the drying device, and the winding device.

[0081] The slot die heads 330 are installed spaced apart from each other in the width direction of the first nonwoven fabric 11A so that the discharge ports face one surface of the first nonwoven fabric 11A between the unwinding device and the winding device. Each discharge port of the slot die heads 330 has a shape extending in the width direction of the first nonwoven fabric 11A. The slot die heads 330 discharge the microcapsule dispersion liquid onto one surface of the first nonwoven fabric 11A.

[0082] To each of the slot die heads 330, a liquid supply device 310 is connected via a liquid supply pipe 320. The liquid supply device 310 includes a pump and supplies the microcapsule dispersion liquid L to the slot die head 330 via the liquid supply pipe 320.

[0083] The drying device dries the first nonwoven fabric 11A to which the microcapsule dispersion liquid L is supplied. The drying device dries the first nonwoven fabric 11A, for example, by heating or by heating and blowing air.

[0084] The winding device winds up the dried first nonwoven fabric 11A, that is, the nonwoven fabric sheet 10A formed by carrying the microcapsules 12 on the first nonwoven fabric 11A, in a roll shape. The winding device includes a motor that rotates a winding shaft for winding up the nonwoven fabric sheet 10A.

[0085] <1.3> Modified Example Various modifications are possible for the gas filter 1A and the nonwoven fabric sheet 10A described above.

[0086] FIG. 5 is a top view of a gas filter according to a modified example. In the gas filter 1A described with reference to FIGS. 1 and 2 etc., in the nonwoven fabric sheet 10A, the first portion P1 forms two strip patterns arranged spaced apart from each other in the width direction. On the other hand, in the gas filter 1B shown in FIG. 5, in the nonwoven fabric sheet 10A, the first portion P1 forms four strip patterns arranged spaced apart from each other in the width direction. Except for this point, the gas filter 1B is the same as the gas filter 1A. Thus, the number of strip patterns formed by the first portion P1 may be 3 or more.

[0087] In the gas filters 1A and 1B, the strip patterns formed by the first portion P1 have the same width W1. One of these strip patterns and another one may have different widths W1.

[0088] Further, in the gas filter 1B, for the pattern pairs each formed from a pair of adjacent strip patterns, the distances D described above are equal to each other. One of these pattern pairs and the other one may have different distances D.

[0089] In the gas filters 1A and 1B, the strip patterns formed by the first portion P1 have equal masses of the microcapsules 12 per unit area. One of these strip patterns and the other one may have different masses of the microcapsules 12 per unit area. In this case, in each of the strip patterns, it is preferable that the mass of the microcapsules 12 per unit area is within the range described above with respect to the mass of the microcapsules 12 per unit area of the first portion P1.

[0090] In the gas filters 1A and 1B, the strip patterns formed by the first portion P1 have the same types of microcapsules 12. One of these strip patterns and the other one may have different types of microcapsules 12.

[0091] <2>Second Embodiment FIG. 6 is a cross-sectional view of a gas filter according to the second embodiment of the present invention.

[0092] The gas filter 1C shown in FIG. 6 is the same as the gas filter 1A described with reference to FIGS. 1 and 2 and the like, except that it further includes a second nonwoven fabric 10B.

[0093] The second nonwoven fabric 10B is laminated on the nonwoven fabric sheet 10A. That is, the second nonwoven fabric 10B and the first nonwoven fabric 11A are laminated on each other, and this laminate constitutes the sheet body. Further, the laminate of the nonwoven fabric sheet 10A and the second nonwoven fabric 10B constitutes the nonwoven fabric sheet.

[0094] For the second nonwoven fabric 10B, the configuration described above for the first nonwoven fabric 11A can be adopted. The second nonwoven fabric 10B may carry microcapsules, but it is preferably free of microcapsules. Here, as an example, it is assumed that the second nonwoven fabric 10B does not carry microcapsules.

[0095] The gas filter 1C has the same effect as the gas filter 1A. In addition, in the gas filter 1C, the second nonwoven fabric 10B can suppress the dropout of the microcapsules 12. Further, when the gas filter 1C is used, for example, in a mask such that the second nonwoven fabric 10B is interposed between the nonwoven fabric sheet 10A and the face, the second nonwoven fabric 10B can prevent the microcapsules 12 contained in the nonwoven fabric sheet 10A from contacting the face. Also, in this case, the second nonwoven fabric 10B can provide the above-described space for turbulent flow between the first portion P1 and the face.

[0096] According to an example, the first nonwoven fabric 11A carries the microcapsules 12 at an equal density on one surface and the other surface thereof. In this case, the second nonwoven fabric 10B may be laminated on either surface of the nonwoven fabric sheet 10A.

[0097] According to another example, the first nonwoven fabric 11A carries the microcapsules 12 at a higher density on one surface thereof as compared with the other surface. For example, the first nonwoven fabric 11A carries the microcapsules 12 at a higher density on the surface coated with the microcapsule dispersion liquid as compared with its back surface.

[0098] In this case, the second nonwoven fabric 10B may be laminated on either surface of the nonwoven fabric sheet 10A. However, in this case, it is preferable that the second nonwoven fabric 10B is laminated on the nonwoven fabric sheet 10A so as to be in contact with or face the surface carrying the microcapsules 12 at a higher density.

[0099] When this arrangement is adopted, the effect of suppressing the detachment of the microcapsules 12 is greater compared to the case where the opposite arrangement is adopted. Further, when the gas filter 1C adopting this arrangement is used in a mask such that the second nonwoven fabric 10B is interposed between the nonwoven fabric sheet 10A and the face, the frequency of contact between the air and the microcapsules 12 during inhalation is higher compared to the case where the gas filter 1C adopting the opposite arrangement is used in a mask such that the second nonwoven fabric 10B is interposed between the nonwoven fabric sheet 10A and the face.

[0100] The gas filter 1C and the nonwoven fabric sheet constituting the same can be variously modified. For example, the nonwoven fabric sheet 10A included therein can be modified in the same manner as described in the first embodiment.

[0101] <3>Third Embodiment FIG. 7 is a cross-sectional view of a gas filter according to the third embodiment of the present invention.

[0102] The gas filter 1D shown in FIG. 7 is the same as the gas filter 1C described with reference to FIG. 6, except that it further includes a third nonwoven fabric 10C.

[0103] The third nonwoven fabric 10C faces the second nonwoven fabric 10B with the nonwoven fabric sheet 10A interposed therebetween. That is, the third nonwoven fabric 10C faces the second nonwoven fabric 10B with the first nonwoven fabric 11A interposed therebetween. The laminate of the first nonwoven fabric 11A, the second nonwoven fabric 10B, and the third nonwoven fabric 10C constitutes a sheet body. Further, the laminate of the nonwoven fabric sheet 10A, the second nonwoven fabric 10B, and the third nonwoven fabric 10C constitutes a nonwoven fabric sheet.

[0104] For the third nonwoven fabric 10C, the configuration described above for the first nonwoven fabric 11A can be adopted. The third nonwoven fabric 10C may carry microcapsules, but it is preferably not carrying microcapsules. Here, as an example, it is assumed that the third nonwoven fabric 10C is not carrying microcapsules.

[0105] The gas filter 1D has the same effect as the gas filter 1B. In addition to this, in the gas filter 1D, not only the second nonwoven fabric 10B but also the third nonwoven fabric 10C can suppress the dropout of the microcapsules 12.

[0106] The gas filter 1D and the nonwoven fabric sheet constituting the same can be variously modified. For example, the nonwoven fabric sheet 10A included therein can be modified in the same manner as described in the first embodiment.

Example

[0107] The tests conducted in relation to the present invention will be described below.

[0108] (Test 1) In this test, the influence of the coating pattern of the microcapsule dispersion liquid on the nonwoven fabric on the air permeability and the contact frequency of the gas with the microcapsules was examined by the following method.

[0109] First, using a manufacturing apparatus having a structure similar to the manufacturing apparatus 300 described with reference to FIG. 4, microcapsules were supported on a nonwoven fabric. Thereby, the samples according to Comparative Example 1 and Examples 1 to 9 were obtained.

[0110] As the nonwoven fabric, a nonwoven fabric Syntex (registered trademark) manufactured by Mitsui Chemicals, Inc. having a width of 150 mm and a basis weight of 40 g / m 2 was used. As the microcapsules, those having a core material containing a fragrance and an average particle diameter of 30 μm were used. The microcapsule dispersion liquid had a solid content of 20% by mass.

[0111] The microcapsule dispersion liquid was applied so that the mass of the microcapsules per unit area of the nonwoven fabric was 3 g / m 2 . In Comparative Example 1 and Examples 1 to 9, the coating pattern of the microcapsule dispersion liquid on the nonwoven fabric and the like were made different as shown in Table 1 below.

[0112]

Table 1

[0113] In Table 1, the "coated portion" and the "uncoated portion" respectively correspond to the strip pattern formed by the first part P1 and the pattern formed by the second part P2. Therefore, the "number of coated portions", the "number of coated portions per unit width", the "width of the coated portion", the "total width of the coated portions", and the "coating amount per unit area in the coated portion" are respectively the number of strip patterns formed by the first part P1, the number of strip patterns per unit width of the nonwoven fabric, the width W1 of the strip pattern, the total of the widths W1, and the mass of the microcapsules per unit area in the first part P1. Also, the "number of uncoated portions" and the "width of the uncoated portion" are respectively the number of patterns formed by the second part P2 and the distance D between the strip patterns. Note that the "total width" is the width W, and the "coating amount per unit area" is the mass of the microcapsules per unit area of the nonwoven fabric.

[0114] Next, for each of the samples according to Comparative Example 1 and Examples 1 to 9 prepared as described above, the air permeability was evaluated by the following method.

[0115] That is, for each of the nonwoven fabric not coated with the microcapsule dispersion (the nonwoven fabric used in the production of the above samples), the sample according to Comparative Example 1, and the samples according to Examples 1 to 9, the air permeability was measured according to Method A (Frazee method) specified in JIS L1096 (2010). Then, with respect to the air volume V0 (cm 3 / cm 2 ·s) obtained for the nonwoven fabric not coated with the microcapsule dispersion, the ratio V1 / V0 of the air volume V1 (cm 3 / cm 2 ·s) obtained for each sample was calculated, and the value expressed as a percentage was defined as the air permeability rate.

[0116] Also, for each of the samples according to Comparative Example 1 and Examples 1 to 9 prepared as described above, the contact frequency of the gas with the microcapsules was evaluated by the following method.

[0117] That is, air was passed through each of the sample according to Comparative Example 1 and the samples according to Examples 1 to 9 at a constant flow rate, and the gas after passing was collected. Next, the concentration of the fragrance in the collected gas was measured as a ni level value using the portable odor sensor XP-329IIIR manufactured by Shin Cosmos Electric Co., Ltd. Then, the fragrance intensity ratio was calculated from these concentrations. Specifically, the ratio C1 / C0 of the measured value C1 obtained for each sample to the measured value C0 obtained for the sample according to Comparative Example 1 was determined, and the fragrance intensity ratio was calculated by multiplying this ratio C1 / C0 by 80%. It can be said that the higher the fragrance intensity ratio, the higher the contact frequency of the gas with the microcapsules.

[0118] The above evaluation results are described in Table 1 above. As shown in Table 1, the samples according to Examples 1 and 9 achieved higher air permeability compared to the sample according to Comparative Example 1. Also, the samples according to Examples 1 and 9 achieved a fragrance intensity ratio equal to or higher than that of the sample according to Comparative Example 1. That is, the contact frequency of the gas with the microcapsules in the samples according to Examples 1 and 9 was equal to or higher than that of the sample according to Comparative Example 1.

[0119] In particular, the samples according to Examples 1, 2, 4, 5, 7, and 8 had a large ratio of the coated portion and achieved significantly higher air permeability compared to the sample according to Comparative Example 1. Also, the samples according to Examples 4 and 9 had a large number of coated portions per unit width and achieved a larger fragrance intensity ratio compared to the sample according to Comparative Example 1.

[0120] (Test 2) In this test, regarding whether the same results as in Test 1 can be obtained when the basis weight of the nonwoven fabric is changed, the following method was used for investigation.

[0121] That is, samples according to Comparative Example 2 and Example 10 were obtained by the same method as described above for the samples according to Comparative Example 1 and Example 7, except that the basis weight of the nonwoven fabric was set to 15 g / m 2 Also, samples according to Comparative Example 2 and Example 10 were obtained by the same method as described above for the samples according to Comparative Example 1 and Example 7, except that the basis weight of the nonwoven fabric was set to 100 g / m 2Samples according to Comparative Example 3 and Example 11 were obtained in the same manner as described above for the samples according to Comparative Example 1 and Example 7, except that

[0122] Then, for the samples according to Comparative Example 2, Comparative Example 3, Example 10, and Example 11, the air permeability was evaluated and the contact frequency of the gas with the microcapsules was evaluated in the same manner as in Test 1. Note that as the measured value C0 in the evaluation of the contact frequency of the gas with the microcapsules, for the samples according to Comparative Example 2 and Example 10, the value obtained for the sample according to Comparative Example 2 was used instead of the value obtained for the sample according to Comparative Example 1, and for the samples according to Comparative Example 3 and Example 11, the value obtained for the sample according to Comparative Example 3 was used instead of the value obtained for the sample according to Comparative Example 1.

[0123] The basis weight of the nonwoven fabric, the coating pattern of the microcapsule dispersion on the nonwoven fabric, and the evaluation results, etc. are shown in Table 2 below.

[0124] [Table 2]

[0125] As shown in Table 2, the samples according to Example 10 and Example 11 achieved higher air permeability and a larger fragrance intensity ratio, respectively, compared to the samples according to Comparative Example 2 and Comparative Example 3. Also, as is clear from the comparison of the evaluation results obtained for the samples according to Example 10 and Comparative Example 2 with the evaluation results obtained for the samples according to Example 7 and Comparative Example 1, and the comparison of the evaluation results obtained for the samples according to Example 11 and Comparative Example 3 with the evaluation results obtained for the samples according to Example 7 and Comparative Example 1, even when the basis weight of the nonwoven fabric was changed, the same results as in Test 1 were obtained.

[0126] (Test 3) In this test, it was investigated by the following method whether the same results as in Test 1 could be obtained when the amount of microcapsules supported on the nonwoven fabric was changed.

[0127] That is, except that the mass of the microcapsules per unit area of the nonwoven fabric (coating amount per unit area) was 0.1 g / m 2 Samples according to Comparative Example 4 and Example 12 were obtained in the same manner as described above for the samples according to Comparative Example 1 and Example 7, except that the mass of the microcapsules per unit area of the nonwoven fabric (coating amount per unit area) was 6.0 g / m 2 Samples according to Comparative Example 5 and Example 13 were obtained in the same manner as described above for the samples according to Comparative Example 1 and Example 7, except that the mass of the microcapsules per unit area of the nonwoven fabric (coating amount per unit area) was 6.0 g / m

[0128] Then, for the samples according to Comparative Example 4 and Comparative Example 5 and Example 12 and Example 13, evaluation of air permeability and evaluation of the contact frequency of the gas with the microcapsules were carried out in the same manner as in Test 1. In addition, as the measured value C0 in the evaluation of the contact frequency of the gas with the microcapsules, for the samples according to Comparative Example 4 and Example 12, the value obtained for the sample according to Comparative Example 4 was used instead of the value obtained for the sample according to Comparative Example 1, and for the samples according to Comparative Example 5 and Example 13, the value obtained for the sample according to Comparative Example 5 was used instead of the value obtained for the sample according to Comparative Example 1.

[0129] The mass of the microcapsules per unit area of the nonwoven fabric (coating amount per unit area), the coating pattern of the microcapsule dispersion liquid on the nonwoven fabric, and the evaluation results, etc. are shown in Table 3 below.

[0130]

Table 3

[0131] As shown in Table 3, the samples according to Example 12 and Example 13 achieved higher air permeability and a larger fragrance intensity ratio, respectively, compared to the samples according to Comparative Example 4 and Comparative Example 5. Further, as is clear from the comparison of the evaluation results obtained for the samples according to Example 12 and Comparative Example 4 with the evaluation results obtained for the samples according to Example 7 and Comparative Example 1, and the comparison of the evaluation results obtained for the samples according to Example 13 and Comparative Example 5 with the evaluation results obtained for the samples according to Example 7 and Comparative Example 1, even when the mass of the microcapsules per unit area of the nonwoven fabric (coating amount per unit area) was changed, the same results as in Test 1 were obtained.

Explanation of Signs

[0132] 1A… gas filter, 1B… gas filter, 1C… gas filter, 1D… gas filter, 10A… nonwoven fabric sheet, 10B… second nonwoven fabric, 10C… third nonwoven fabric, 11A… first nonwoven fabric, 12… microcapsules, 110… fibers, 300… manufacturing apparatus, 310… liquid supply apparatus, 320… liquid supply pipe, 330… slot die head, D… distance, L… microcapsule dispersion liquid, P1… first part, P2… second part, W… width, W1… width.

Claims

1. A sheet body including a first non-woven fabric and a plurality of microcapsules carried on the first non-woven fabric, wherein portions of the first non-woven fabric carrying the plurality of microcapsules form a plurality of strip-shaped patterns arranged spaced apart from each other in the width direction, and the plurality of strip-shaped patterns each have a width of 1 mm or more and a distance between adjacent ones of 1 mm or more, a non-woven fabric sheet.

2. The non-woven fabric sheet according to claim 1, wherein the plurality of strip-shaped patterns each have a width of 300 mm or less and a distance between adjacent ones of 300 mm or less.

3. The non-woven fabric sheet according to claim 1, wherein the total area of the plurality of strip-shaped patterns occupies a ratio in the range of 5 to 90% of the area of the first non-woven fabric.

4. The non-woven fabric sheet according to claim 1, wherein the number of the plurality of strip-shaped patterns per unit width of the first non-woven fabric is in the range of 2 to 500 pieces / m.

5. The plurality of microcapsules, the mass per unit area of the first nonwoven fabric is 0.005 to 19 g / m ２ The nonwoven fabric sheet according to claim 1, which is within the range of.

6. The sheet body has a basis weight in the range of 1 to 1000 g / m ２ The nonwoven fabric sheet according to claim 1, which is within the range of

7. The non-woven fabric sheet according to claim 1, wherein the sheet body further includes a second non-woven fabric laminated with the first non-woven fabric.

8. The non-woven fabric sheet according to claim 7, wherein the second non-woven fabric does not carry microcapsules.

9. The non-woven fabric sheet according to claim 7, wherein the sheet body further includes a third non-woven fabric laminated with the first non-woven fabric and the second non-woven fabric.

10. The non-woven fabric sheet according to claim 9, wherein the second non-woven fabric and the third non-woven fabric do not carry microcapsules.

11. The non-woven fabric sheet according to claim 9, wherein the third non-woven fabric faces the second non-woven fabric with the first non-woven fabric interposed therebetween.

12. A gas filter including the non-woven fabric sheet according to any one of claims 1 to 11.

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