JP2012197971A - Humidification element and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compact humidification element featuring efficient liquid absorption and excellent rigidity when exposed to dampness.SOLUTION: The compact humidification element featuring efficient liquid absorption and excellent rigidity when exposed to dampness can be manufactured by forming space in a compact for the purpose of having space to let an air flow pass through the compact of nonwoven fiber structure where moist-heat adhesive fibers are properly glued and further by disposing the compacts to be disposed adjacent to each other. In addition, as the intersection point of the moist-heat adhesive fibers is strong, processing such as slit processing, which makes effective use of wet area per humidification element volume, can be easily performed.

Description

  The present invention relates to a humidifying element used for a vaporizing humidifier, a drain transpiration plate, or the like.

  A general air conditioning system creates a comfortable living environment by controlling humidity as well as air temperature. As this humidification method, water is vaporized by oscillating ultrasonic waves in the water stored in the water tank, and the water is sprayed by air stream, or the heater is placed in the water tank and heated directly to steam. There is a steam type that generates water, or a vaporization type that humidifies by adding water to the humidifying material and vaporizing moisture by applying water around it.

  In recent years, air conditioners have been downsized and various humidifiers have been commercialized for the purpose of changing the living environment and securing a large indoor space. Formability and form stability may be required.

  In the shape of the humidifying element, there is disclosed a humidifying element in which a spacer is provided between a plurality of humidifying element substrates to form voids (see, for example, Patent Document 1). The humidifying element of Patent Document 1 has a high strength when retaining water and is excellent in workability when processing the humidifying element. However, when compared with a humidified element obtained by corrugating a thin humidified element, the wet area per volume of the humidified element is reduced, resulting in an increase in the size of the humidified element.

  Further, there is disclosed a humidifying element made of a sheet-like material such as a nonwoven fabric, a knitted fabric, and a woven fabric, and having a cross section cut in the thickness direction of the sheet-like material in a corrugated shape (see, for example, Patent Document 2). .) However, the nonwoven fabric, knitted fabric, woven fabric and the like used in Patent Document 2 have a problem in that the shape of the gap is liable to collapse because the stiffness when wet is weak.

  Furthermore, a substrate for a humidifying element that includes wet heat adhesive fibers and is excellent in water absorption has been proposed (for example, see Patent Document 3). The substrate of Patent Document 3 is excellent in form retention when wet, but depending on the shape and arrangement of the element substrate, the intended liquid absorption, liquid retention and moisture release properties may not be obtained. It was.

JP-A-8-219504 JP-A-7-167469 JP 2009-222243 A

  Accordingly, an object of the present invention is to provide a compact humidifying element that is excellent in liquid absorbency and wet rigidity.

  As a result of intensive studies to achieve the above-mentioned problems, the present inventors have used a molded body composed of a non-woven fiber structure bonded with wet heat-adhesive fibers, and formed a void for allowing an air flow to pass through the molded body. It is possible to produce a compact humidifying element that is excellent in liquid absorbency and rigidity at the time of wetting by forming voids in the molded body so that the molded bodies are adjacent to each other and arranging the molded bodies adjacent to each other. The present invention has been completed.

  That is, the present invention relates to a molded article composed of a non-woven fiber structure bonded with wet heat adhesive fibers, wherein a void is formed in the molded article so as to have a gap for air flow to pass through, and It is a humidifying element that is arranged adjacent to each other so that the gap interval between the molded bodies is 0.5 to 15 mm, and preferably a cross section obtained by cutting the humidifying element in the thickness direction is formed in a waveform. More preferably, the humidifying element is characterized in that it is slit in a plurality of places parallel to the water absorption direction, and is shaped in a wave shape so that the slit cut surfaces do not overlap.

  In the present invention, voids are formed in the molded body so as to have voids for allowing an air flow to pass through the molded body having a non-woven fiber structure in which fibers are appropriately bonded by wet heat-adhesive fibers. By arranging the bodies so as to be adjacent to each other, it is possible to manufacture a humidifying element that is excellent in liquid absorption and wet rigidity and that is compact. In addition, since the intersections between the wet-heat adhesive fibers are strong, it is easy to perform processing such as slit processing that effectively uses the wet area per volume of the humidifying element.

  The humidifying element of the present invention comprises a molded body that includes wet heat adhesive fibers, the fibers are fixed by fusion of the wet heat adhesive fibers, and has a non-woven fiber structure. The molded body usually has not only high liquid absorbency and liquid retention characteristic unique to the fiber structure, but also by arranging the arrangement of fibers constituting the nonwoven fiber structure and the bonding state between the fibers within a predetermined range. "Bending behavior (behavior that has high bending stress and retains stress even after bending beyond the point where the maximum bending stress is exhibited and tries to recover when the stress is released)" Light weight ”and“ Surface hardness (characteristics that do not easily deform even when a load is applied to the surface in the thickness direction) ”, and it is hard to break. Liquidity, liquid retention, shape retention and slit processability are ensured at the same time.

  As described later, the molded body having the nonwoven fiber structure used for the humidifying element of the present invention is obtained by applying high-temperature (superheated or heated) water vapor to the web containing the wet heat-adhesive fiber, thereby wet-adhesive fiber. It is obtained by exhibiting an adhesive action at a temperature below the melting point of the fiber and partially bonding the fibers. That is, it is obtained by point-bonding or partial-bonding single fibers and bundle-like bundled fibers so as to form a “scrum” while holding moderately small voids under wet heat.

  The content of the wet heat adhesive fiber in the molded article having the nonwoven fiber structure of the present invention can be selected from the range of 10 to 100% by weight depending on the shape and type of the humidifying element. When a hard humidifying element is required, it is preferable that the ratio of wet and heat adhesive fibers is large, and it is 80% by weight or more, preferably 90% by weight or more, and more preferably 95% by weight or more. When the ratio of wet heat adhesive fibers is within this range, a high surface hardness and bending behavior can be ensured, and a molded article having good slit workability can be obtained.

The wet heat adhesive fiber is composed of at least a wet heat adhesive resin. The wet heat adhesive resin only needs to be able to flow or easily deform at a temperature that can be easily realized by high-temperature steam and to exhibit an adhesive function. Specifically, a thermoplastic resin that is softened with hot water (for example, about 80 to 120 ° C., particularly about 95 to 100 ° C.) and can be self-adhered or bonded to other fibers, for example, a cellulose-based resin (C such as methylcellulose) _1-3 alkylcelluloses, hydroxyalkyl C _1-3 alkyl celluloses such as hydroxypropyl cellulose, carboxy C _1-3 alkyl cellulose or a salt thereof, such as carboxymethyl cellulose), polyalkylene glycol resin (polyethylene oxide, poly C ₂ such as polypropylene oxide _-4 and alkylene oxide), polyvinyl resins (polyvinyl pyrrolidone, polyvinyl ether, polyvinyl alcohol, polyvinyl acetal, etc.), acrylic copolymers and alkali metal salts [(meth) acrylic acid, (meth) acrylate A copolymer containing a unit composed of an acrylic monomer such as an amide or a salt thereof], a modified vinyl copolymer (a vinyl monomer such as isobutylene, styrene, ethylene, vinyl ether, and maleic anhydride) A copolymer with an unsaturated carboxylic acid or its anhydride or a salt thereof), a polymer having a hydrophilic substituent (polyester, polyamide, polystyrene or the like having a sulfonic acid group, a carboxyl group, or a hydroxyl group introduced) And salts thereof), aliphatic polyester resins (polylactic acid resins, etc.), and the like. Furthermore, among polyolefin resins, polyester resins, polyamide resins, polyurethane resins, thermoplastic elastomers or rubbers (such as styrene elastomers), it can be softened at the temperature of hot water (high-temperature steam) to exhibit an adhesive function. Other resins are also included.

These wet heat adhesive resins can be used alone or in combination of two or more. The wet heat adhesive resin is usually composed of a hydrophilic or water-soluble polymer. Among these wet heat adhesive resins, vinyl alcohol polymers such as ethylene-vinyl alcohol copolymers, polylactic acid resins such as polylactic acid, (meth) acrylic copolymers containing (meth) acrylamide units, A vinyl alcohol polymer containing an α-C _2-10 olefin unit such as ethylene or propylene, particularly an ethylene-vinyl alcohol copolymer is preferred.

  In the ethylene-vinyl alcohol copolymer, the ethylene unit content (copolymerization ratio) is, for example, about 10 to 60 mol%, preferably about 20 to 55 mol%, and more preferably about 30 to 50 mol%. When the ethylene unit is in this range, a unique property of having wet heat adhesiveness but not hot water solubility is obtained. If the proportion of the ethylene units is too small, the ethylene-vinyl alcohol copolymer easily swells or gels with low-temperature steam (water), and its form is likely to change only once wetted with water. On the other hand, when the ratio of the ethylene unit is too large, the hygroscopicity is lowered, and fiber fusion due to wet heat is difficult to be exhibited, so that it is difficult to ensure practical strength. When the ratio of the ethylene unit is particularly in the range of 30 to 50 mol%, the processability into a sheet or plate is particularly excellent.

  The saponification degree of the vinyl alcohol unit in the ethylene-vinyl alcohol copolymer is, for example, about 90 to 99.99 mol%, preferably 95 to 99.98 mol%, more preferably 96 to 99.97 mol. %. When the saponification degree is too small, the thermal stability is lowered, and the stability is lowered by thermal decomposition or gelation. On the other hand, if the degree of saponification is too large, it is difficult to produce the fiber itself.

  Although the viscosity average degree of polymerization of an ethylene-vinyl alcohol-type copolymer can be selected as needed, it is 200-2500, for example, Preferably it is 300-2000, More preferably, it is about 400-1500. When the degree of polymerization is within this range, the balance between spinnability and wet heat adhesion is excellent.

  The cross-sectional shape (cross-sectional shape perpendicular to the fiber length direction) of the wet heat-adhesive fiber is a general solid cross-sectional shape, such as a round cross-section or an irregular cross-section [flat, elliptical, polygonal, 3-14 Leaf shape, T-shape, H-shape, V-shape, dogbone (I-shape, etc.)], and may be a hollow cross-section. Further, the wet heat adhesive fiber may be a composite fiber composed of a plurality of resins including at least a wet heat adhesive resin. The composite fiber only needs to have the wet heat adhesive resin on at least a part of the fiber surface, but from the viewpoint of adhesiveness, the wet heat adhesive resin continuously occupies at least a part of the surface in the length direction. Is preferred.

  Examples of the cross-sectional structure of the composite fiber in which the wet heat adhesive fiber occupies the surface include a core-sheath type, a sea-island type, a side-by-side type, a multilayer bonding type, a radial bonding type, and a random composite type. Among these cross-sectional structures, the core-sheath structure (that is, the sheath part is wet-heat-adhesive, which is a structure in which the wet-heat adhesive resin occupies the entire surface continuously in the length direction because it is a highly adhesive structure. A core-sheath structure made of resin is preferred.

  In the case of a composite fiber, wet heat adhesive resins may be combined with each other, but may be combined with non-wet heat adhesive resins. Non-wet heat adhesive resins include water-insoluble or hydrophobic resins such as polyolefin resins, (meth) acrylic resins, vinyl chloride resins, styrene resins, polyester resins, polyamide resins, polycarbonate resins, Examples include polyurethane resins and thermoplastic elastomers. These non-wet heat adhesive resins can be used alone or in combination of two or more.

  Among these non-wet heat adhesive resins, from the viewpoint of heat resistance and dimensional stability, resins having a melting point higher than that of wet heat adhesive resins (particularly ethylene-vinyl alcohol copolymers), such as polypropylene resins and polyester resins. Resins and polyamide resins, particularly polyester resins and polyamide resins are preferred from the standpoint of excellent balance between heat resistance and fiber-forming properties.

Polyester resins include aromatic polyester resins such as poly C _2-4 alkylene arylate resins (polyethylene terephthalate (PET), polytrimethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, etc.), especially polyethylene such as PET. A terephthalate resin is preferred. In addition to the ethylene terephthalate unit, the polyethylene terephthalate resin is not limited to other dicarboxylic acids (for example, isophthalic acid, naphthalene-2,6-dicarboxylic acid, phthalic acid, 4,4'-diphenyldicarboxylic acid, bis (carboxyphenyl) ethane. , 5-sodium sulfoisophthalic acid, etc.) and diols (for example, diethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, cyclohexane-1,4-dimethanol, Units composed of polyethylene glycol, polytetramethylene glycol, etc.) may be included at a ratio of about 20 mol% or less.

  Polyamide resins include polyamides 6, polyamides 66, polyamides 610, polyamides 10, polyamides 12, polyamides 6-12 and other aliphatic polyamides and copolymers thereof, half-synthesized from aromatic dicarboxylic acids and aliphatic diamines. Aromatic polyamide is preferred. Further, these polyamide resins may also contain other copolymerizable units.

  In the case of a composite fiber composed of a wet heat adhesive resin and a non-wet heat adhesive resin, the ratio (mass ratio) of both can be selected according to the structure (for example, core-sheath structure), and the wet heat adhesive resin is on the surface. Is not particularly limited, for example, wet heat adhesive resin / non-wet heat adhesive resin = 90/10 to 10/90, preferably 80/20 to 15/85, and more preferably 60/40 to 20/80. Degree. If the proportion of wet heat adhesive resin is too large, it will be difficult to ensure the strength of the fiber, and if the proportion of wet heat adhesive resin is too small, it will be difficult to have the wet heat adhesive resin continuously in the length direction of the fiber surface. Thus, the wet heat adhesiveness is lowered. This tendency is the same when the wet heat adhesive resin is coated on the surface of the non-wet heat adhesive fiber.

  The average fineness of the wet heat adhesive fiber can be selected, for example, from the range of about 0.01 to 100 dtex, preferably 0.1 to 50 dtex, more preferably 0.5 to 30 dtex (particularly 1 to 10 dtex) depending on the application. Degree. When the average fineness is in this range, the balance between the strength of the fiber and the expression of wet heat adhesion is excellent.

  The average fiber length of the wet heat adhesive fibers can be selected, for example, from a range of about 10 to 100 mm, preferably 20 to 80 mm, more preferably about 25 to 75 mm (particularly 35 to 55 mm). When the average fiber length is within this range, the fibers are sufficiently entangled, so that the mechanical strength of the molded body is improved.

  The crimp rate of the wet heat adhesive fiber is, for example, about 1 to 50%, preferably 3 to 40%, more preferably about 5 to 30% (particularly 10 to 20%). The number of crimps is, for example, about 1 to 100 pieces / 25 mm, preferably about 5 to 50 pieces / 25 mm, and more preferably about 10 to 30 pieces / 25 mm.

In addition to the above-mentioned fibers, the molded body having a non-woven fiber structure used for the humidifying element of the present invention may further contain non-wet heat adhesive fibers. Non-wet heat adhesive fibers include polyester fibers (polyethylene terephthalate fibers, polytrimethylene terephthalate fibers, polybutylene terephthalate fibers, aromatic polyester fibers such as polyethylene naphthalate fibers), polyamide fibers (polyamide 6, polyamide 66, Aliphatic polyamide fibers such as polyamide 11, polyamide 12, polyamide 610, polyamide 612, semi-aromatic polyamide fibers, aromatic polyamide fibers such as polyphenylene isophthalamide, polyhexamethylene terephthalamide, poly p-phenylene terephthalamide, etc. ), Polyolefin fibers (poly C _2-4 olefin fibers such as polyethylene and polypropylene), acrylic fibers (acrylonitrile-vinyl chloride copolymer, etc.) Acrylonitrile fiber having acrylonitrile unit), polyvinyl fiber (polyvinyl acetal fiber, etc.), polyvinyl chloride fiber (polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, vinyl chloride-acrylonitrile copolymer fiber, etc.) ), Polyvinylidene chloride fiber (fiber such as vinylidene chloride-vinyl chloride copolymer, vinylidene chloride-vinyl acetate copolymer), polyparaphenylene benzobisoxazole fiber, polyphenylene sulfide fiber, cellulosic fiber (for example, rayon fiber) And acetate fibers). These non-wet heat adhesive fibers can be used alone or in combination of two or more.

The non-wet heat adhesive fibers described above can be appropriately selected and used according to the form of the humidifying element and the method of use. When emphasizing water absorption or the like, hydrophilic fibers with high hygroscopicity such as polyvinyl alcohol fibers and cellulose fibers can be mentioned, and it is particularly preferable to use cellulose fibers. Cellulosic fibers include natural fibers (cotton, wool, silk, hemp, etc.), semi-synthetic fibers (acetate fibers such as triacetate fiber), regenerated fibers (rayon, polynosic, cupra, lyocell (for example, registered trademark name: “ Tencel ") etc.). Among these cellulosic fibers, for example, semi-synthetic fibers such as rayon can be suitably used, and when combined with wet heat adhesive fibers containing an ethylene-vinyl alcohol copolymer, the affinity with wet heat adhesive fibers is high. Adhesiveness is improved, and a molded article having high mechanical properties can be obtained. Further, when hydrophilic fibers are used, for example, liquid retention and liquid absorbability with respect to an aqueous liquid are increased, while moldability and form retention tend to be decreased.
On the other hand, when emphasizing the moisture-releasing property of aqueous liquids, hydrophobic fibers with low hygroscopicity, for example, polyolefin fibers, polyester fibers, polyamide fibers, particularly polyester fibers (polyethylene terephthalate) having an excellent balance of properties. It is preferable to use fibers. When these hydrophobic fibers are combined with wet heat adhesive fibers containing an ethylene-vinyl alcohol copolymer, a molded body having a nonwoven fiber structure for a humidifying element excellent in hydrophobicity and drainage of aqueous liquid can be obtained. .

  The average fineness of the non-wet heat adhesive fiber can be selected, for example, from a range of about 0.01 to 100 dtex, preferably 0.1 to 50 dtex, more preferably 0.5 to 30 dtex (particularly 1 to 10 dtex), depending on the application. Degree. On the other hand, average fiber length can be selected from the range of about 10-100 mm, for example, Preferably it is 20-80 mm, More preferably, it is about 25-75 mm (especially 35-55 mm).

  The ratio (mass ratio) of the wet heat adhesive fiber and the non wet heat adhesive fiber in the case of mixing the non wet heat adhesive fiber is also determined according to the type of the humidifying element, etc. / 90-100 / 0, More preferably, it can select from the range of 20 / 80-100 / 0. When manufacturing a hard molded object, the one where the ratio of wet heat adhesive fiber is large is preferable, and the ratio (mass ratio) of both is wet heat adhesive fiber / non-wet heat adhesive fiber = 80/20 to 100/0. , Preferably 90/10 to 100/0, more preferably about 95/5 to 100/0. When the ratio of the wet heat adhesive fibers is within this range, a molded product that can ensure high surface hardness, WET rigidity, and slit processability can be obtained.

  For the molded body or the fibers constituting the molded body, a conventional additive, for example, a stabilizer (a heat stabilizer such as a copper compound, an ultraviolet absorber, a light stabilizer, an antioxidant, etc.), a dispersant. , Fine particles, colorants, antistatic agents, flame retardants, plasticizers, lubricants, crystallization rate retarders, and the like. These additives can be used alone or in combination of two or more. These additives may be carried on the surface of the molded body or may be contained in the fiber.

  The molded body constituting the humidifying element has a non-woven fiber structure obtained from the web composed of the fibers, the shape of which can be selected according to the application, and is a circular or elliptical cross section, or a polygonal shape. Ordinarily, it is in the form of a sheet or plate.

  Furthermore, in the molded body constituting the humidifying element, the non-woven fiber has an appropriate rigidity (morphological stability) and has a good balance of liquid absorption, liquid retention, light weight (low density) and slit workability. In order to have a structure, it is necessary that the arrangement state and the adhesion state of the fibers constituting the nonwoven fiber web are appropriately adjusted. That is, it is desirable that the fibers constituting the fiber web are arranged so as to intersect each other while being arranged substantially parallel to the surface of the fiber web (non-woven fiber). Furthermore, the molded body constituting the humidifying element is preferably fused at the intersection where the fibers intersect. In particular, a molded product that requires high form stability and slit workability is a bundle-like fusion in which fibers other than the intersections are fused in a bundle of several to several tens in a portion where the fibers are arranged substantially in parallel. Fibers may be formed. These fibers form a “scrum” by partially forming a fused structure at the intersection of single fibers, the intersection of bundle fibers, or the intersection of single fibers and bundle fibers A structure (a structure in which fibers are bonded at an intersection and entangled like a mesh, or a structure in which fibers are bonded at an intersection to constrain adjacent fibers to each other) to achieve the desired bending behavior, surface hardness, etc. it can. In the present invention, it is desirable that such a structure is distributed substantially uniformly along the surface direction and the thickness direction of the fiber web.

The phrase “arranged substantially parallel to the fiber web surface” as used above indicates a state in which a portion where a large number of fibers are locally arranged in the thickness direction does not exist repeatedly. .
More specifically, when an arbitrary cross-section of the fiber web of the formed body is observed with a microscope, the existence ratio (number ratio) of fibers continuously extending in the thickness direction over 30% or more of the thickness of the fiber web. The state is 10% or less (particularly 5% or less) with respect to the total fibers in the cross section.

  Fibers are arranged parallel to the fiber web surface when there are many fibers oriented in the thickness direction (perpendicular to the web surface) and the fiber arrangement is disturbed around the fiber web. This is because an unnecessarily large void is generated in the woven fiber, and the bending strength and surface hardness of the molded body are reduced. Therefore, it is preferable to reduce this gap as much as possible. For this purpose, it is desirable to arrange the fibers as parallel to the fiber web surface as possible.

  Furthermore, in the present invention, anisotropy is imparted to the liquid absorbency by orienting the fibers in parallel with the fiber web surface. That is, the humidifying element base material has high liquid absorbency in the length direction of the fiber because the fiber has a certain orientation.

  In particular, when a load is applied in the thickness direction of the molded body when the molded body is in the form of a sheet or plate, if there is a large void, the void is crushed by the load and the surface of the molded body is easily deformed. . Furthermore, when this load is applied to the entire surface of the molded body, the thickness tends to be reduced as a whole. Such a problem can be avoided if the molded body itself is made of a resin filling without voids, but the liquid retaining property is lowered.

  On the other hand, in order to reduce the deformation in the thickness direction due to the load, it is conceivable to make the fibers thinner and more densely filled with the fibers, but when trying to ensure lightweight and breathability with only thin fibers, The rigidity of the fiber becomes low, and conversely the bending stress decreases. In order to secure bending stress, it is necessary to increase the fiber diameter to some extent. However, if thick fibers are simply mixed, large voids are easily formed near the intersections of the thick fibers and deformed in the thickness direction. It becomes easy to do.

  Therefore, in the molded body used for the humidifying element of the present invention, the fibers cross each other by arranging the fibers in parallel along the surface direction of the web and dispersing (or directing the fibers in a random direction). By adhering at the intersection, a small gap is generated to ensure liquid retention and drainage. Furthermore, an appropriate surface hardness is ensured by such a continuous fiber structure.

The said molded object used for the humidification element of this invention is characterized by high WET bending stress. The molded body is a WET maximum bending stress in at least one direction (preferably in all directions) is 1N / mm ² or more, preferably 1.5 N / mm ² or more, more preferably 1.8 N / mm ² or more There may be. If the maximum bending stress is too small, it is easily broken by its own weight or a slight load when used in a plate shape.

The apparent density of the molded body used in the humidifying element of the present invention can be selected from the range of 0.15 to 0.5 g / cm ³ depending on the application, and the liquid absorbency and the retention can be maintained while maintaining the form stability. From the point which also maintains the balance of liquid property and slit workability, for example, 0.18 to 0.4 g / cm ³ , preferably 0.20 to 0.38 g / cm ^3, more preferably 0.25 to 0.35 g. / Cm ³ . If the apparent density is too low, the liquid retention is improved, but the sucking height, surface hardness, mechanical properties, and slit processability are lowered. On the other hand, if the apparent density is too high, mechanical properties such as water absorption and hardness are reduced. Although the characteristics can be secured, the liquid retention and water absorption speed are reduced.

Basis weight of the molded body used in the humidifier element of the present invention, for example, be selected from the range of 100~5000g / ^{m 2,} preferably not 250~3000g / ^{m 2,} more preferably a 400~1000g / ^{m 2.} If the basis weight is too small, it will be difficult to ensure hardness and formability. If the basis weight is too large, the web will be too thick, and high-temperature steam will not be able to sufficiently enter the inside of the web in wet heat processing, and it will be uniform in the thickness direction. It becomes difficult to make a simple structure.

  When the molded body used in the humidifying element of the present invention is plate-shaped or sheet-shaped, the thickness is not particularly limited, but can be selected from a range of 0.3 to 10 mm, for example, 0.4 to 5 mm, preferably It is 0.5-3 mm, More preferably, it is 1-2 mm. If the thickness is too thin, it is difficult to ensure the hardness. If the thickness is too thick, the ratio of the surface area that releases the contained moisture decreases, and the efficiency of humidifying the air decreases, so the size of the humidifying element increases.

  The molded body used in the humidifying element of the present invention has a high water absorption rate, excellent liquid absorbency, and high liquid retention. Specifically, the water absorption speed of the humidifying element is, for example, 10 seconds or less, preferably 5 seconds or less, more preferably 1 second or less, according to a method according to JIS L1907 dropping method. The water absorption rate (water retention rate) is, for example, 100% by mass or more, preferably 200% by mass or more (for example, 200 to 5000% by mass), more preferably 500% by mass or more (for example, according to JIS L1907). 500-3000 mass%).

  Moreover, when using as a suction type humidification element as shown in FIG. 1, the water absorption which absorbs water above a liquid level (Byreck method) is useful. This is because the larger the capacity, the larger the contact area with the air in the humidifying element when the air is humidified. In the present invention, in order to develop sufficient water absorption, the birec-type suction length after 600 seconds from the start of water absorption is preferably 8 cm or more, more preferably 10 cm or more, and further preferably 15 cm or more. is there.

  Moreover, since the said molded object used for the humidification element of this invention has high form stability, even if it absorbs water | moisture content, there is little expansion | swelling of a volume. At the same time, it is difficult for a substrate having water absorbency with large deformation to exhibit good moisture-releasing properties, so it is necessary to make this balance within a good range. Specifically, the dimensional expansion rate when water is sufficiently absorbed (saturated) (for example, in the case of a plate-like molded body, the respective dimensional expansion rates in the vertical direction, the horizontal direction, and the thickness direction) is, for example, 4% or less (for example, 0.0001 to 4%), preferably 0.001 to 3.5%, and more preferably 0.01 to 3% (particularly 0.1 to 2%).

  Since the molded body used in the humidifying element of the present invention has the above form stability and water retention, when used as a humidifying element, a large number of the humidifying elements are raised in the form of fins from the water-absorbing part, It is possible to humidify the air as it passes around it. Moreover, when a large humidification capability is required, it can be compensated by raising the fins in the air passage in parallel at appropriate intervals.

The manufacturing method of the said molded object used for the humidification element of this invention is demonstrated in detail below.
In the present invention, first, a fiber containing the wet heat adhesive fiber is formed into a web. As a method for forming the web, a conventional method, for example, a direct method such as a spun bond method or a melt blow method, a card method using melt blow fibers or staple fibers, a dry method such as an air array method, or the like can be used.
Among these methods, a card method using melt blown fibers or staple fibers, particularly a card method using staple fibers is widely used. Examples of the web obtained using staple fibers include a random web, a semi-random web, a parallel web, and a cross-wrap web. Of these webs, a semi-random web and a parallel web are preferred when the proportion of bundled fused fibers is increased.

  Next, the obtained fiber web is sent to the next step by a belt conveyor, and then exposed to superheated or high-temperature steam (high-pressure steam) flow to obtain a shaped body having a non-woven fiber structure. That is, when the fiber web transported by the belt conveyor passes through the high-speed high-temperature steam flow ejected from the nozzle of the steam spraying device, the wet-heat adhesive fibers are fused by the sprayed high-temperature steam, and the fiber Each other (wet heat adhesive fibers or wet heat adhesive fibers and other fibers) are three-dimensionally bonded. In particular, since the fiber web in the present invention has air permeability, high-temperature water vapor penetrates into the inside, and a molded body having a substantially uniform fusion state can be obtained.

  The belt conveyor to be used is not particularly limited as long as it can be subjected to high-temperature steam treatment while basically compressing the fiber web used for processing to a desired density, and an endless conveyor is preferably used. In addition, it may be a general single belt conveyor, or may be transported by combining two belt conveyors as necessary and sandwiching the web between both belts. By carrying in this way, when processing a fiber web, it can suppress that the form of the fiber web conveyed by external forces, such as water used for processing, high temperature steam, and vibration of a conveyor, changes. It is also possible to control the density and thickness of the processed non-woven fibers by adjusting the distance between the belts.

  In order to supply water vapor to the fiber web, a conventional water vapor jet apparatus is used. As this steam spraying device, a device capable of spraying steam substantially uniformly over the entire width of the web at a desired pressure and amount is preferable. When two belt conveyors are combined, water vapor is supplied to the web through a water-permeable conveyor belt or a conveyor net placed on the conveyor. A suction box may be attached to the other conveyor. Excess water vapor that has passed through the fiber web can be sucked and discharged by the suction box. Further, in order to perform steam treatment on both sides of the front and back of the fiber web at a time, in a conveyor opposite to the conveyor on which the steam spraying device is mounted, more than the portion on which the steam spraying device is mounted. You may install another water vapor | steam injection apparatus in the conveyor of a downstream part. If there is no downstream steam injection device and suction box, and if you want to steam-treat the front and back of the fiber web, you can reverse the front and back of the fiber web that has been treated once and pass it through the processing device again. Good.

  The endless belt used for the conveyor is not particularly limited as long as it does not hinder the conveyance of the fiber web or the high-temperature steam treatment. However, when high-temperature steam treatment is performed, the surface shape of the belt may be transferred to the surface of the fiber web depending on the conditions. In particular, when it is desired to obtain a molded body having a flat surface, a net with a fine mesh may be used. The upper limit is about 90 mesh, and a net that is roughly coarser than 90 mesh (for example, a net of about 10 to 50 mesh) is preferable. A finer mesh net than this has low air permeability and makes it difficult for water vapor to pass through. The mesh belt is made of metal, heat-treated polyester resin, polyphenylene sulfide resin, polyarylate resin (fully aromatic polyester resin), aromatic polyamide resin, etc. from the viewpoint of heat resistance against water vapor treatment. A heat resistant resin or the like is preferable.

  Since the high-temperature steam sprayed from the steam spraying device is an air stream, unlike the hydroentanglement process or the needle punch process, the fibers in the fiber web that is the object to be processed enter the inside of the fiber web without largely moving. . It is considered that due to the invasion action and wet heat action of the water vapor flow into the fiber web, the water vapor flow efficiently covers the surface of each fiber existing in the fiber web in a wet heat state, and uniform heat bonding becomes possible. In addition, since this treatment is performed in a very short time under a high-speed air flow, the heat conduction of the water vapor to the fiber surface is sufficient, but the treatment is completed before the heat conduction to the inside of the fiber is sufficiently achieved. For this reason, the entire fiber web to be processed is not easily crushed or deformed such that its thickness is impaired by the pressure or heat of high-temperature steam. As a result, the wet heat bonding is completed so that the degree of bonding in the surface and the thickness direction is substantially uniform without causing large deformation in the fiber web. Further, since heat can be sufficiently conducted to the inside of the non-woven fiber structure as compared with the dry heat treatment, the degree of fusion in the surface and the thickness direction becomes substantially uniform.

Furthermore, when obtaining a molded body having a high surface hardness and bending strength, when the high-temperature steam is supplied to the web for processing, the web to be processed is placed between a conveyor belt or rollers with a desired apparent density (for example, It is important to expose to high temperature water vapor in a state compressed to about 0.3 to 1 g / cm ³ . In particular, when trying to obtain a relatively high-density molded body, it is necessary to compress the fiber web with sufficient pressure when processing with high-temperature steam. Furthermore, it is also possible to adjust to a target thickness and density by securing an appropriate clearance between rollers or between conveyors. In the case of a conveyor, since it is difficult to compress the web at a stretch, it is preferable to set the belt tension as high as possible and gradually narrow the clearance from the upstream of the steam treatment point. Furthermore, it is processed into a molded body having desired bending hardness, surface hardness, lightness, and air permeability by adjusting the steam pressure and the processing speed.
At this time, if it is desired to increase the hardness, the back side of the endless belt on the opposite side of the nozzle across the web is made of a stainless steel plate or the like so that the steam cannot pass through. Since it reflects here, it adhere | attaches more firmly by the heat retention effect of vapor | steam. Conversely, when light adhesion is required, a suction box may be provided to discharge excess water vapor to the outside.

  The nozzle for injecting the high-temperature steam may be a plate or a die in which predetermined orifices are continuously arranged in the width direction, and may be arranged so that the orifices are arranged in the width direction of the fiber web to be supplied. There may be one or more orifice rows, and a plurality of rows may be arranged in parallel. A plurality of nozzle dies having a single orifice array may be installed in parallel.

  When using a type of nozzle having an orifice in the plate, the thickness of the plate may be about 0.5 to 1 mm. The orifice diameter and pitch are not particularly limited as long as the target fiber fixation is possible, but the orifice diameter is usually 0.05 to 2 mm, preferably 0.1 to 1 mm, more preferably. It is about 0.2 to 0.5 mm. The pitch of the orifices is usually about 0.5 to 3 mm, preferably about 1 to 2.5 mm, and more preferably about 1 to 1.5 mm. If the orifice diameter is too small, the processing accuracy of the nozzle becomes low and the processing becomes difficult, and the operational problem that clogging is likely to occur easily occurs. On the other hand, if it is too large, the water vapor jetting power is reduced. On the other hand, if the pitch is too small, the nozzle holes become too dense and the strength of the nozzle itself is reduced. On the other hand, when the pitch is too large, there is a case where high-temperature water vapor does not sufficiently hit the web, so that the web strength is lowered.

  The high-temperature steam is not particularly limited as long as the target fiber can be fixed, and may be set according to the material and form of the fiber used. The pressure is, for example, 0.1 to 2 MPa, preferably 0.2 to The pressure is about 1.5 MPa, more preferably about 0.3 to 1 MPa. If the water vapor pressure is too high or too strong, the fibers that make up the web may move more than necessary, causing turbulence, or the fibers may melt too much to partially retain the fiber shape. There is. On the other hand, if the pressure is too weak, it may not be possible to give the web the amount of heat necessary for fiber fusion, or water vapor may not penetrate the web, resulting in fiber fusion spots in the thickness direction. In addition, it may be difficult to control the uniform ejection of water vapor from the nozzle.

  The temperature of the high-temperature steam is, for example, about 70 to 150 ° C, preferably about 80 to 120 ° C, and more preferably about 90 to 110 ° C. The processing speed of the high temperature steam is, for example, 200 m / min or less, preferably 0.1 to 100 m / min, and more preferably about 1 to 50 m / min.

  If necessary, it is also possible to impart designability to a molded body obtained by applying predetermined uneven patterns, characters, pictures, etc. to the conveyor belt and transferring them. Further, it may be laminated with other materials to form a laminated body, or may be processed into a desired form (various shapes such as a columnar shape, a quadrangular prism shape, a spherical shape, an ellipsoidal shape) by molding. In particular, in the present invention, since it is hard and excellent in shape stability, it can be processed into various shapes without impairing the properties relating to the absorption and release of liquid such as liquid absorption and liquid retention.

  After the fibers of the fiber web are partially wet-heat bonded in this way, moisture may remain in the resulting molded body having the nonwoven fiber structure, and the web may be dried as necessary. Regarding drying, it is necessary that the surface of the molded body that is in contact with the heating body for drying does not lose the fiber form due to the heat of drying, so that the fiber form can be maintained. . For example, a large dryer such as a cylinder dryer or tenter used for drying nonwoven fabrics may be used, but the remaining moisture is very small and can be dried by a relatively light drying means. Therefore, a non-contact method such as far-infrared irradiation, microwave irradiation, electron beam irradiation, or a method of blowing or passing hot air is preferable.

  Further, as described above, the molded body is obtained by adhering wet heat-adhesive fibers with high-temperature steam, but partially (such as bonding between molded bodies obtained by wet heat bonding), other conventional methods such as Further, they may be bonded by a processing method such as partial hot-pressure fusion (such as hot embossing) or mechanical compression (such as needle punch).

  The wet heat adhesive fibers can also be fused by dipping the fiber web in hot water. However, it is difficult to control the fiber adhesion rate by such a method, and a molded product with high uniformity of the fiber adhesion rate is obtained. Is difficult. The reason for this is that the wet heat adhesiveness differs depending on the position due to the air contained in the fiber web, the influence on the structure caused by this air being pushed out of the fiber web, the wet heat bonded fiber web It can be presumed that the deformation of the fine structure inside the fiber by the take-off roller when taking out from the hot water or the difference in the deformation of the fine structure in the vertical direction due to the weight of the hot water contained in the taken-out fiber web.

The humidifying element of the present invention thus obtained has a void in the molded body so that the molded body composed of the non-woven fiber structure bonded with wet heat adhesive fibers has a void for air flow to pass through. Each molded body is formed and arranged adjacent to each other, preferably the molded body has a WET bending stress of 1 N / mm ² or more, and a birec-type suction length 600 seconds of 8 cm or more. The ratio is 100% or more, and the molded body is further assembled so that the wet area per volume of the humidifying element is 5 cm ² / cm ³ .
Furthermore, in order to increase the wet area per volume of the humidifying element, the cross section obtained by cutting the humidifying element in the thickness direction is formed into a corrugated shape, and further, slit cutting is performed at a plurality of locations parallel to the water absorption direction, thereby reducing the surface area of the slit surface. By increasing, it is possible to obtain high humidification performance while maintaining the form as the humidifying element.

Here, the wet area per volume of the humidifying element described above refers to the wet area of the humidifying element (the molded body used for the humidifying element is wet with water and in contact with air) when the humidifying element having a constant volume is prepared. The area is divided by the volume of the humidifying element.
The wet area per volume of the humidifying element is, for example, preferably 1 cm ² / cm ³ or more, preferably 1.3 cm ² / cm ³ or more, and more preferably 1.5 cm ² / cm ³ or more. When this value is too small, the humidification performance is lowered and the size of the humidifying element is increased.

The form of the humidifying element is not particularly limited as long as the wet area per volume of the humidifying element is 1 cm ² / cm ³ or more. Specifically, there are a suction type and a dripping type as shown in FIGS. As shown in the figure, voids are formed in the molded body composed of a nonwoven fiber structure bonded by wet heat adhesive fibers so that the molded body has voids through which an air flow passes. As long as they are arranged adjacent to each other. Furthermore, in order to make a compact humidification element without impairing the water absorption performance of the molded body composed of the nonwoven fiber structure bonded with the wet heat adhesive fiber, the molded body cut at a plurality of slits in parallel with the water absorption direction. As shown in FIG. 1 (g) or FIG. 2 (i), the slit cut surfaces are formed into a wave shape so as not to overlap each other, and a plurality of the formed products formed in a wave shape are stacked. It is also possible to perform processing so as to minimize the area in contact with the air and to form a gap for air circulation.
In the slit processing, by slitting in parallel with the water absorption direction, the water absorption path is not blocked and the surface area of the cut surface can be increased. When slitting is performed perpendicular to the water absorption direction, the surface area of the cut surface increases, but the water absorption path is blocked.

,
The slit width is not particularly limited as long as it can maintain the self-supporting property of the humidifying element, but is, for example, 1 to 15 mm, preferably 2 to 10 mm, and more preferably 3 to 7 mm. If the slit width is too narrow, the rigidity is reduced, and if it is too wide, the increase in surface area due to slit processing is reduced.

  In order to increase the surface area due to the slit processing to increase the wet area per volume of the humidifying element, it is preferable to process the slit processing surface into a shape that makes contact with air as much as possible, as shown in FIG. It can be formed into a humidifying element shape. This shape has a small bonding surface between the molded bodies used in the humidifying element and can form a void for air circulation, so that the wet area per volume of the humidifying element can be increased.

  In this invention, when the humidification element is arrange | positioned adjacently, the clearance gap between adjacent humidification elements needs to be 0.5-15 mm. If the gap between the humidifying elements is less than 0.5 mm, the adjacent humidifying elements do not have gaps, so the wet area per volume of the humidifying element is small, and the humidifying performance is inferior. On the other hand, even when the gap between the humidifying elements exceeds 15 mm, the wet area per volume of the humidifying element becomes small, and the humidifying performance is inferior. Preferably it is 1-10 mm, More preferably, it is 1-5 mm.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples. Each physical property value in the examples was measured by the following method.
In the examples, “%” is based on mass unless otherwise specified.

[Weight per unit g / m ² ]
Measured according to JIS L1913 “Testing method for general short fiber nonwoven fabric”.

[Thickness mm, apparent density g / cm ³ ]
The thickness was measured according to JIS L1913 “Test method for general short fiber nonwoven fabric”, and the apparent density was calculated from the measured thickness and the basis weight.

[Crimped number]
Evaluation was performed according to JIS L1015 “Testing method for chemical fiber staples” (8.12.1).

[WET bending stress]
It measured according to A method (three-point bending method) among the methods as described in JIS K7017. At this time, the measurement sample was immersed in a beaker containing tap water for 5 minutes and then air-dried for 1 minute. A 25 mm wide × 80 mm long sample was used, the distance between fulcrums was 50 mm, and the test speed was 2 mm / min. Went. In the present invention, the maximum stress (peak stress) in this measurement result chart is defined as the maximum bending stress. The bending stress was measured in the MD direction and the CD direction. Here, the MD direction refers to a state in which the measurement sample is collected so that the web flow direction (MD) is parallel to the long side of the measurement sample, while the CD direction refers to the long side of the measurement sample. A state in which a measurement sample is collected so that the web width direction (CD) is parallel.

[Water absorption speed (wicking method)]
The water absorption rate was measured according to JIS-L1907 “Test method for water absorption of textile products”. One drop of 0.05 g / droplet of water from a height of 10 mm was dropped on the sample, and the time until the drop was sucked into the sample was measured.

[Suction book (Bilec method)]
The wicking length was measured according to JIS-L1907 “Test method for water absorption of textile products”. Measurement was performed at 10 seconds, 60 seconds, and 600 seconds.

[Water retention rate (water absorption rate)]
Measured according to JIS L1907 “Water absorption”. A sample of 5 cm × 5 cm square size is prepared and the mass (molded body mass) is measured. This sample was submerged in water for 30 seconds, then pulled up, suspended for 1 minute in the air with one corner up, the surface water was drained, and the mass (mass after water absorption) was measured. It calculated based on the following formula | equation.
Water absorption (mass%) = <(mass after water absorption−molded body mass) / molded body mass> × 100

[Expansion coefficient during water absorption]
The sample was cut to the same size as in the water retention test and allowed to stand for 24 hours under the same conditions. Then, the dimension under the standard condition (L1) was measured in the MD direction, CD direction, and thickness direction to completely cover the sample. After immersing in distilled water for 5 minutes, pull it up and drain it vertically by hanging for 1 minute, and then similarly measure the length, width and thickness of the sample after absorption (L2 ) And the dimensional change rate was calculated according to the following formula. For each measurement value, an average value of values measured for five samples was used.
Dimensional change rate (%) = [(L2) − (L1)] / (L1) × 100

[Wet area]
The area where the humidifying element base material was wet with water and in contact with air was calculated as the wet area. The following formula shows the calculation method when there is no surface area increasing processing such as slit processing. Depending on the height of the suction length e), either one of the formulas 1) and 2) is selected and calculated.

Formula 1) Suction length e)> Base material height for humidifying element a)-Water depth d) (Fig. 4)

Wet area = [humidity element substrate height a) −water depth d)] × 2 [humidity element substrate thickness b) + humidification element substrate width c)] × humidification element number f)

Formula 2) Suction length e) ≤ Humidifying element base material height a)-Water depth d) (Fig. 5)

Wet area = [(e)] × 2 [b) + c)] × f)

When the surface area increases due to slitting or the like, the increase in wet area accompanying the increase in surface area is added.

[Wet area per volume of humidifying element]
Calculated from the following formula.
Wet area per volume of humidifying element = Wet area of humidifying element / Volume of the device where the humidifying element is installed (inner dimensions)

[Humidification performance]
A plurality of molded articles each having a non-woven fiber structure of 15 cm (width) × 15 cm (height) were prepared, and as shown in FIG. 6, made of polypropylene of 30 cm (vertical) × 15 cm (horizontal) × 20 cm (height) After being inserted into the humidification amount measuring device at an arbitrary interval, tap water was filled in the device to a depth of 3 cm, and the weight (W1) of the humidification measuring device was measured. Next, air was sent into the apparatus with a hot air generator and humidified for 1 hour. Further, air having an air volume of 150 cm ³ / hr, a temperature of 35 ° C., and a relative humidity of 15% was sent into an air hole having a diameter of 10 cm by a hot air generator, and after humidifying for 1 hour, the weight (W2) of the experimental apparatus was measured again. The humidification performance was calculated from the following formula.

Humidification performance = W2-W1

[Washing durability]
A molded body composed of a non-woven fiber structure for a humidifying element after the humidifying performance test was used as a sample, and was washed 10 times with a commercially available household washing machine. After that, after assembling the humidifying element and filling with tap water in the same manner as that performed in the humidification amount measurement test, the form of the humidifying element was visually observed and evaluated in three stages according to the concentration standard.
A: The shape before washing is almost retained.
◯: Although there is no significant change in shape, the humidifying element base material is partially bent, the humidifying element base materials are in contact with each other, and the air circulation gap is reduced.
X: The shape is greatly deformed, and the air circulation gap is remarkably lowered.

[Example 1]
(1) Core-sheath type composite staple fiber in which the core component is polyethylene terephthalate and the sheath component is an ethylene-vinyl alcohol copolymer (ethylene content 44 mol%, saponification degree 98.4 mol%) as wet heat adhesive fiber (“Sophista” manufactured by Kuraray Co., Ltd., fineness 2.2 dtex, fiber length 51 mm, core-sheath mass ratio = 50/50, number of crimps 21/25 mm, crimp ratio 13.5%) was prepared.
(2) Using this core-sheath type composite staple fiber, a card web having a basis weight of 100 g / m ² is prepared by a card method, and five webs are stacked to form a card web having a total basis weight of 500 g / m ^2. The web was transferred to a belt conveyor equipped with a 50 mesh, 500 mm wide stainless steel endless net. In addition, the belt conveyor which has the same metal mesh is equipped in the upper part of the metal mesh of this belt conveyor, and it rotated in the same direction at the same speed, respectively, and used the belt conveyor which can adjust the space | interval of these metal meshes arbitrarily. .
(3) Next, a steam web is introduced into the water vapor jet device provided in the lower conveyor, and 0.4 MPa of high temperature water vapor is ejected (perpendicularly) from this device in the thickness direction of the card web. Then, a steam treatment was performed to obtain a molded body having a nonwoven fiber structure. In this steam spraying device, a nozzle is installed in the lower conveyor so as to spray high-temperature steam toward the web via a conveyor net, and a suction device is installed in the upper conveyor. Further, another jetting device, which is a combination of the arrangement of the nozzle and the suction device reversed, is installed on the downstream side in the web traveling direction of the jetting device, and steam treatment is performed on both the front and back sides of the web. did.
In addition, the hole diameter of the water vapor | steam injection nozzle was 0.3 mm, and the vapor | steam injection apparatus with which the nozzle was arranged in 1 row at 1 mm pitch along the width direction of the conveyor was used. The processing speed was 3 m / min, and the distance (distance) between the upper and lower conveyor belts on the nozzle side and the suction side was 2 mm. The nozzles were arranged on the back side of the conveyor belt so as to be almost in contact with the belt.
(4) The obtained molded body had a board-like form. This was cut into a belt conveyor flow direction (MD direction) 1500 mm and a width direction (CD direction) 400 mm. Moreover, the sample for evaluation was cut out from the obtained molded object.
(5) Next, the molded body was cut into 20 cm (width) × 15 cm (height), and the cut sample was slit with 5 mm width and 13 cm. The slit processed sample was thermoformed so as to have the form shown in FIG. 3 to obtain a sample for evaluating the humidifying element. In addition, it was made for the clearance gap between adjacent humidification elements to be 4 mm. The evaluation results are shown in Table 1.

[Example 2]
A humidified element was produced in the same manner as in Example 1 except that a card web having a basis weight of 100 g / m ² was prepared and seven sheets thereof were stacked. The evaluation results are shown in Table 1.

[Example 3]
A core-sheath type composite staple fiber (manufactured by Kuraray Co., Ltd., “Sophista”) and rayon fiber (fineness: 1.4 dtex, fiber length: 44 mm) are blended at a ratio of 80/20 (mass ratio) to a weight of about 100 g / m. ^A humidifying element was produced in the same manner as in Example 1 except that the card web of No. ² was prepared and five sheets thereof were stacked. The evaluation results are shown in Table 1.

[Example 4]
A humidifying element was produced in the same manner as in Example 1 except that the nonwoven fiber structure molded body was not slit. The evaluation results are shown in Table 1.

[Comparative Example 1]
A humidifying element was produced in the same manner as in Example 1 except that the gap between adjacent humidifying elements was 20 mm. The evaluation results are shown in Table 1.

[Comparative Example 2]
A humidifying element was produced in the same manner as in Example 4 except that the gap between adjacent humidifying elements was 0 mm. The evaluation results are shown in Table 1.

  As is clear from the results in Table 1, the non-woven fiber structure molded body for the humidifier element of the example is excellent in suction performance, water retention performance, and WET rigidity. Furthermore, the humidification element manufactured by processing the nonwoven fabric structure molded body into a predetermined shape is particularly excellent in humidification performance and form retention.

  The non-woven fiber structure molded body for the humidifying element of Comparative Example 1 has a large gap of 20 mm between adjacent non-woven fiber structure molded bodies and a small wet area per volume of the humidifying element. .

  The non-woven fiber structure molded body for the humidifying element of Comparative Example 2 does not have a gap between adjacent non-woven fiber structure molded bodies, and the humid area per humid element volume is small.

  Since the humidifying element of the present invention is a compact humidifying element that is excellent in liquid absorption and WET rigidity, it can be used in houses, vehicles such as offices and houses, and specifically, humidifiers for home use and commercial use. It can be used as an air cleaner, a drain transpiration plate, etc.

The schematic diagram which shows the structure of the suction type humidification element in this invention. The schematic diagram which shows the structure of the dripping type humidification element in this invention. The surface photograph which shows an example of the humidification element which gave the slit process in this invention. The schematic diagram which shows the humidification element at the time of calculating | requiring a wet area (Formula 1). The schematic diagram which shows the humidification element at the time of calculating | requiring a wet area (Formula 2). The schematic diagram which shows the experimental apparatus at the time of humidification performance measurement.

Claims (3)

  In a molded body composed of a non-woven fiber structure bonded by wet heat adhesive fibers, voids are formed in the molded body so as to have voids for air flow to pass through, and gaps between the molded bodies A humidifying element arranged adjacent to each other so that the interval is 0.5 to 15 mm.   The humidifying element according to claim 1, wherein a section obtained by cutting the humidifying element in the thickness direction is formed in a waveform.   The humidifying element according to claim 1 or 2, wherein the humidifying element is formed into a wave shape so that slits are cut at a plurality of positions parallel to the water absorption direction and the slit cut surfaces do not overlap.

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