JP2011062816A - Moisture absorbing and releasing material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a moisture absorbing and releasing material which effectively suppresses aging deterioration of moisture absorptiveness and is excellent in shape holding property (in particular crease processing suitability). <P>SOLUTION: The moisture absorbing and releasing material is provided wherein a laminated body comprising a moisture absorbing fiber substance 1 and a shape holding fiber material 2 laminated on both faces thereof contains 2-20 pts.wt. resin component based on 100 pts.wt. moisture absorbing fiber substance. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a moisture absorbing / releasing material. More specifically, the present invention relates to a material used as a filter (filter medium) such as a humidifier.

Humidifiers are devices used to increase or maintain indoor humidity in buildings, houses, and the like, and various types of devices are commercially available for various business use and general home use. As a method (method) for humidification, various methods such as a vaporization method, a spray method, and a steam method are known. In particular, the vaporization type is used in many humidifiers because it can vaporize water at room temperature. In humidification by vaporization, normal temperature water is absorbed by a filter and the filter is ventilated, so that the absorbed moisture is released into the atmosphere.
Filters used in humidifiers are required not only to absorb water but also to retain their shape. That is, in order to be mountable as an element of a humidifier, sufficient rigidity is required to maintain a specific shape as a filter.

In this regard, various filters have been developed so far. For example, a base sheet (X) made of a thermoplastic resin, an adhesive layer (Y) made of an adhesive resin, and a water absorbing layer (Z) are laminated sheets in which at least three layers are laminated in this order, The water absorbing layer (Z) comprises a nonwoven fabric (a) composed of fibers obtained by melt spinning a thermoplastic water absorbent resin, a nonwoven fabric (b) comprising fibers obtained by melt spinning a thermoplastic resin, a nonwoven fabric (a) and a nonwoven fabric (b). Adhesive composite non-woven fabric (c), non-woven fabric (a) or non-woven fabric (b) water-absorbing sheet (d) composed of thermoplastic water-absorbing resin and / or foamed sheet composed of thermoplastic water-absorbing resin containing foaming agent At least one selected from the group consisting of a layer formed by bonding (e) and a layer formed by bonding a water-absorbing sheet (d) or a foamed sheet (e) to the composite nonwoven fabric (c). There is a certain water-retaining laminate sheet (Patent Document 1). Further, by using a heat-adhesive nonwoven fabric containing a heat-adhesive fiber and a water-absorbing fiber as a base material, and impregnating the base material with a synthetic resin emulsion containing a hydrophilic porous fine powder and an antibacterial agent, A vaporization accelerator for a humidifier is known in which a porous porous fine powder and an antibacterial agent are attached to a substrate via a synthetic resin (Patent Document 2). Further, for example, a composite in which a fiber web is integrated on one side or both sides of a network structure, the fiber web contains 30% by weight or more of cellulose fibers, and the composite has a water retention amount of 250 g / m ^2.
As described above, a moisture absorbing / releasing material characterized by an air permeability of 50 to 700 cm ³ / cm ² · sec and a compressive strength when wet of 0.1 N / 5 cm or more has been proposed (Patent Document 3).

JP-A-8-318587 Utility registration model No. 3001285 JP 2004-250839 A

  However, these materials in the prior art still have room for further improvement in terms of sufficiently achieving both water absorption (hygroscopicity) and shape retention.

  In particular, water-absorbing materials such as rayon are known to cause dimensional changes and bending resistance (stiffness) reduction when containing water. In order to prevent these, resin processing is generally performed for the purpose of hard finishing, but it is necessary to impregnate a corresponding resin component in order to impart crease processing suitability. Here, the suitability for crease processing means, for example, when a water absorbing material is loaded in a humidifier, the water absorbing material is creased under heating to form a bellows-like sheet (corrugated cardboard), etc., and after cooling The property which can maintain the creased form substantially. This suitability for crease processing is an industrially important characteristic for water-absorbing materials as well as water absorption. When the crease processing suitability is insufficient or missing, it cannot be processed into a desired shape and cannot be put into practical use even if the water absorption is excellent.

  From such a viewpoint, it is indispensable for the water-absorbing material to impregnate a sufficient amount of the resin component so that the crease processing suitability can be exhibited. However, according to the study by the present inventors, it has been found that the water absorption of conventional water-absorbing materials greatly decreases with time due to repeated moisture absorption and release, and that the cause is the use of a large amount of resin components. ing. That is, the conventional product with a relatively large amount of resin used has a problem that even if the initial water absorption is good, the water absorption rapidly decreases with time.

  Accordingly, a main object of the present invention is to provide a moisture absorbing / releasing material that is effectively suppressed in deterioration of water absorption with time and has excellent shape retention (particularly suitability for crease processing).

  As a result of intensive studies in view of the problems of the prior art, the present inventors have found that the above object can be achieved by impregnating a specific laminate with a predetermined amount of a resin component, and the present invention has been completed. It was.

That is, the present invention relates to the following moisture absorbing / releasing material.
1. The laminate comprising the water-absorbing fibrous material and the shape-retaining fibrous material laminated on both sides thereof contains 2 to 20 parts by weight of a resin component with respect to 100 parts by weight of the hygroscopic fibrous material. Moisture absorption and desorption material.
2. Item 2. The moisture absorbing / releasing material according to Item 1, wherein the water absorbent fibrous material has one or more through holes penetrating in a tubular shape from one plane to the other plane of the material.
3. Item 3. The moisture absorbing / releasing material according to Item 2, wherein the ratio of the total area of the through holes on the plane of the water absorbent fibrous material is 20 to 80%.
4). Item 3. The moisture absorbing / releasing material according to Item 2, wherein the average area per through hole is 0.5 to ² mm ² .
5. Item 2. The moisture absorbing / releasing material according to Item 1, wherein the water-absorbing fibrous material is a nonwoven fabric containing rayon fibers.
6). Item 2. The moisture absorbing / releasing material according to Item 1, wherein the shape-retaining fibrous material is a polyester nonwoven fabric having a structure in which a plurality of long fiber layers having different finenesses are stacked.
7). Item 2. The moisture absorbing / releasing material according to Item 1, which is used as a moisture absorbing / releasing material for a humidifier.
8). A molded body obtained by bending the moisture absorbing / releasing material according to Item 1.
9. A humidifier element in which a molded body obtained by bending the moisture absorbing / releasing material according to item 1 is provided on a substrate.

  According to the moisture absorbing / releasing material of the present invention, since a predetermined amount of the resin component is contained in the laminate having a specific configuration, it is possible to effectively reduce the water absorption over time due to repeated moisture absorption / release. In addition to being able to suppress or prevent, excellent shape retention, crease processing suitability, etc. can be exhibited. In particular, in the case of a three-layer structure of shape retention layer / water absorption layer / shape retention layer, these water absorption properties, shape retention properties, crease processing suitability, etc. can be obtained more reliably.

  Hygroscopic materials with such features include humidifier filters (filter materials), heat exchanger elements, building materials, agricultural sheets, daily necessities (evaporation filter materials such as deodorants and fragrances) Can be used in various fields.

The schematic diagram of the material for moisture absorption / release of the present invention is shown. 1A is a cross-sectional view, and FIG. 1B is a plan view. The schematic diagram of the material for moisture absorption / release of the present invention is shown. 1A is a cross-sectional view, and FIG. 1B is a plan view. It is a schematic diagram which shows the procedure of a crease | work process aptitude test in an Example etc. It is a schematic diagram which shows the sample arrangement | positioning method of the crease | work process aptitude test in an Example etc.

  The moisture absorbing / releasing material of the present invention (the material of the present invention) is a laminate comprising a water absorbing fibrous material and a shape-retaining fibrous material laminated on both sides thereof, and the resin component is 100 parts by weight of the hygroscopic fibrous material. 2 to 20 parts by weight is included.

  FIG. 1 is a schematic view showing an example of the material of the present invention. Fig.1 (a) is the figure seen from the side surface (cross section). FIG.1 (b) is a top view of a hygroscopic fibrous material. As shown in FIG. 1 (a), the material of the present invention has shape-retaining fibrous materials 2, 2 (hereinafter “shape-retaining layers”) on both surfaces of a hygroscopic fibrous material 1 (hereinafter also referred to as “water-absorbing layer”). A predetermined amount of a resin component (not shown) is further included in a laminate in which the laminate is laminated. In the material of FIG. 1, the shape retention layer is laminated on both sides of the water absorption layer without any gap. In other words, the hygroscopic fibrous material or the shape-retaining fibrous material is laminated in a flat state without taking a wavy or uneven shape. By laminating and fixing in such a state, it is possible to deform or process the laminated body in an integrated state. In addition to these layers, the material of the present invention may be laminated with other layers. In particular, a material having a three-layer structure of “shape retention layer / water absorption layer / shape retention layer” as described above is water absorbent, It is preferable from the viewpoint of crease processing suitability.

  In the present invention, shape-retaining fibrous materials are laminated on the upper surface and the lower surface of the hygroscopic fibrous material, respectively, but the two shape-retaining fibrous materials in this case may be the same or different from each other. It may be a thing. In particular, in the present invention, it is desirable to use the same two shape-retaining fiber materials from the viewpoint of dimensional accuracy and the like.

Hygroscopic fibrous material The material of the hygroscopic fibrous material is not limited as long as it has water absorption (hydrophilicity), and any of natural fiber, synthetic fiber, regenerated fiber, and the like may be used. For example, rayon, cellulose (cotton, pulp), vinylon, acrylic and the like can be mentioned. Among these, rayon (rayon fiber) can be preferably used in the present invention.

  The form of the hygroscopic fibrous material may be either a woven fabric or a non-woven fabric, but in the present invention, it is preferable to use a non-woven fabric. As the nonwoven fabric, for example, a nonwoven fabric obtained by a known production method such as a dry method, a wet method, a spun bond method, a melt blown method, a spun lace method, and these processed products can also be used.

  Moreover, in this invention, 1 type (s) or 2 or more types of fibers can be used for a water absorbing fiber material. In the present invention, a nonwoven fabric containing rayon fibers can be suitably used. That is, in addition to a nonwoven fabric made of rayon fibers alone, a nonwoven fabric made of rayon fibers and other fibers can be preferably used. More specifically, a nonwoven fabric made of rayon fiber and polyester fiber can be used.

  The fineness of the hygroscopic fibrous material can be selected according to the desired hygroscopicity (water absorption), processability, etc. in addition to the type of fiber used, but is generally about 1.1 to 16.7 dtex. In particular, it is preferably 2.2 to 11.1 dtex.

The hygroscopic fibrous material is usually in the form of a sheet. The thickness is preferably about 0.1 to 20 mm, and particularly preferably 0.2 to 10 mm. If it is 0.1 mm or less, the performance as a moisture absorbing / releasing material cannot be obtained, and if it is 20 mm or more, it may be too thick to be processed by a crease machine. Also, the basis weight of the sheet is not limited to, usually a 30~300g / ^{m 2} about, it is preferable that the particular 40~200g / ^{m 2.}

  In the present invention, it is possible to employ a material in which the water-absorbing fibrous material has one or more through holes penetrating in a tubular shape from one plane of the material to the other plane. By using a hygroscopic fibrous material having a through-hole penetrating in a tubular shape, higher water absorption can be obtained. FIG. 2 shows an example of the material of the present invention having the through hole. As shown to Fig.2 (a), the through-hole 3 penetrated in a tubular shape (tubular shape when seen from the cross section) is formed from the upper surface to the lower surface of the water absorbent fibrous material. As the formation of the through hole 3, for example, a known perforation method such as a method of forming by punching or a method of forming by heating / melting can be employed. In addition, the well-known or commercially available thing can be used for the nonwoven fabric itself which has such a through-hole.

  The ratio (opening ratio) of the total area of the through holes on the plane of the water-absorbing fibrous material is usually 20 to 80%, preferably 20 to 50%. In FIG. 2B, the ratio is (total area of the through holes 3 (that is, total area of the colored portions in FIG. 2B)) / (area of the water-absorbent fibrous material 1 (that is, FIG. 2). (B) shows the total area of the colored portion and the white portion).

The shape (planar shape) of the through hole is not particularly limited, and for example, one or more of various shapes such as a circle, an ellipse, a square, a rectangle, a triangle, a polygon, and a star may be adopted. it can. The size of the through hole depends on the desired air permeability, water absorption, etc., but is generally set appropriately so that the average area per one through hole is in the range of 0.5 to ² mm ^2. Is preferred.

The number (density) of the through holes depends on the size of the through holes and the like, but generally can be appropriately set within a range of about 10 to 100 / cm ² .

Shape-retaining fibrous material The shape-retaining fibrous material is not limited as long as it has a predetermined rigidity, and can be appropriately selected from various materials. For example, synthetic resins such as polyester, polyamide, and polyolefin can be used. Among these, synthetic resins with high hydrophobicity can be used more suitably.

  The form-retaining fibrous material may be either a woven fabric or a non-woven fabric, but in the present invention, it is preferable to use a non-woven fabric. As the nonwoven fabric, for example, a nonwoven fabric obtained by a known production method such as a dry method, a wet method, a spun bond method, a melt blown method, a spun lace method, and these processed products can also be used.

  In the shape-retaining fibrous material, one type or two or more types of fibers can be used. In this invention, the nonwoven fabric containing a polyester fiber can be used suitably. That is, in addition to a nonwoven fabric made of polyester fiber alone, a nonwoven fabric made of polyester fiber and other fibers can be preferably used.

  The fineness of the shape-retaining fibrous material can be selected according to the desired hygroscopicity, workability, etc. in addition to the type of fiber used, but is generally about 1.1 to 33.3 dtex, especially 2 .2 to 16.7 dtex is preferable. In the present invention, it is particularly preferable to use a polyester nonwoven fabric having a structure in which a plurality of long fiber layers having different finenesses are stacked. A commercial item can be used for such a nonwoven fabric.

The shape-retaining fibrous material is usually a sheet. The thickness is about 0.1 to 0.8 mm, and preferably 0.1 to 0.3 mm. If it is 0.1 mm or less, shape retention performance may not be obtained. Moreover, when it is 0.8 mm or more, it becomes hard and there is a possibility that desired crease processing suitability or the like cannot be obtained. Also, the basis weight of the sheet is not limited to, usually a 10 to 100 g / ^{m 2} approximately, it is preferable that the particular 12~50g / ^{m 2.}

Laminate As shown in FIG. 1 or FIG. 2, the material of the present invention has a laminate comprising a water-absorbing fibrous material and a shape-retaining fibrous material laminated on both sides thereof, and a resin component. In the laminate, the layer structure is not limited, but a layer having a three-layer structure of “shape-retaining layer / water-absorbing layer / shape-retaining layer” is particularly preferable from the viewpoints of dimensional accuracy, water absorption, suitability for crease processing, and the like. In the case of different from the above three-layer structure, for example, in the case of a three-layer structure composed of “water-absorbing layer / shape-retaining layer / water-absorbing layer”, a two-layer structure composed of “water-absorbing layer / shape-retaining layer”, etc. Etc. may not be obtained.

  In the material of the present invention, each material (each layer) in the laminate is bonded and fixed by an adhesive component. The adhesive component is not particularly limited as long as the materials can be bonded to each other. For example, it can be appropriately selected from commercially available adhesives (particularly hot melt adhesives) according to the materials of the hygroscopic fibrous material and the shape-retaining fibrous material. As the hot melt adhesive, either a liquid type or a solid type can be used. For example, a solid hot melt adhesive formed in a web shape (net shape) is interposed between the materials and can be suitably bonded by hot pressing. In addition, at least one of the hygroscopic fibrous material and the shape-retaining fibrous material can be preliminarily made to contain a heat-sealing fiber and can be laminated with the heat-sealing fiber.

Resin component materials of the invention, the resin component is contained 2 to 20 parts by weight with respect to the hygroscopic fibrous material 100 parts by weight of the laminate. In the present invention, the resin component is contained (impregnated) and fixed, for example, in a gap (between fibers) of the fiber structure of the laminate.

  The type of the resin component is not limited. For example, acrylic resin, polyurethane resin, polyester resin, ethylene-vinyl acetate resin, styrene acrylic resin, vinyl acetate resin, polystyrene resin, vinylidene chloride resin, vinyl chloride resin, polyamide resin, phenol Resin and the like. These can be used alone or in combination of two or more. Among these, a hydrophobic thermoplastic resin can be suitably used. By using a hydrophobic thermoplastic resin, a decrease in water absorption is small even when the resin content is high, and it is difficult to swell, so that a desired film strength can be ensured. In addition, the use of a thermoplastic resin is advantageous in terms of suitability for crease processing and the like because processing by heating can be easily performed. From such a viewpoint, for example, an acrylic resin or the like can be suitably used.

  The resin content is 2 to 20 parts by weight, preferably 2 to 15 parts by weight, based on 100 parts by weight of the hygroscopic fibrous material. When the content is less than 2 parts by weight, desired crease processing suitability cannot be obtained. In addition, when the content exceeds 20 parts by weight, the rigidity becomes too large to make a crease process, and it is difficult to suppress a decrease in hygroscopicity over time due to moisture absorption / release of the material of the present invention. Become.

  In addition, the rigidity (with water) of the material of the present invention varies depending on the purpose of use of the material of the present invention, the type of shape-retaining fiber material, etc., but usually the bending resistance by the measuring method based on JIS-L-1096. Is preferably 50 mm or more, particularly 100 mm or more. Such a moisture absorption / release material having bending resistance requires only a small amount of resin used during resin processing, and as a result, a decrease in water absorption with time is effectively suppressed or prevented.

The material of the present invention is usually in the form of a sheet. The thickness is preferably about 0.2 to 20 mm, and particularly preferably 0.3 to 1.0 mm. The basis weight of the sheet but is not limited, usually with 50 to 300 g / ^{m 2} approximately, it is preferable that the particular 50 to 200 g / ^{m 2.}

  The use of the material of the present invention is not limited as long as it is used for moisture absorption and desorption, and can be widely used for applications that need to reversibly absorb and desorb moisture. That is, it can be used for the same application as a conventional hygroscopic sheet. For example, it can be used for various devices and components (humidifiers, heat exchangers, daily necessities, home appliances, etc.) as vaporization filters, air cooling materials, dehumidifying materials, humidity control materials, etc. Can also be used. In particular, when used in a humidifier, for example, a molded body formed by bending the material of the present invention can be mounted as it is or as an element provided with the molded body on a substrate.

Step Although manufacturing production method of the present invention the material is not limited, to form, for example, 1) the water-absorbent fibrous laminate shape retention fibrous material on both sides by interposing the adhesive component of the material of the present invention materials, 2 The material of the present invention can be suitably produced by a production method including a step of impregnating the obtained laminate with a resin component.

  The formation process of a laminated body should just adhere | attach each material by interposing the above adhesive components. For example, a laminate can be obtained by pressing while heating using a hot melt adhesive as an adhesive component. As such a lamination method (condition) itself, a known method can be adopted.

  Next, the obtained laminate is impregnated with a resin component. Such a resin processing method itself can be carried out in the same manner as a known method. For example, the material of the present invention in which the resin component is contained (impregnated) in the laminate can be obtained by immersing the laminate in a synthetic resin emulsion and then drying the laminate. Thereby, for example, the material of the present invention in which the resin component is filled and fixed at least in the gap (between fibers) of the shape-retaining fibrous material can be obtained. As described above, it is preferable to use a hydrophobic thermoplastic resin as the resin component, and examples thereof include an acrylic resin. Further, the concentration of the emulsion can be appropriately determined within a range of usually about 1 to 80% by weight. In addition to the resin component, the emulsion may contain, for example, an antibacterial agent, an antifungal agent, a coloring material, a surfactant (emulsifier), a water absorption aid, and the like as necessary.

  The features of the present invention will be described more specifically with reference to the following examples and comparative examples. However, the scope of the present invention is not limited to the examples.

Properties of the fibrous material Table 1 shows the properties of the hygroscopic fibrous material and the shape-retaining fibrous material used in the examples and comparative examples.

Measuring method / evaluation method of material properties The measuring method / evaluation method of material properties in the examples and comparative examples were carried out as follows.

(1) Water absorption (bi-leg method)
It implemented based on JIS-L-1907. More specifically, the sample was cut into 2.5 cm × 25 cm, 1 cm from the end of the sample was immersed in water, and the distance of sucking up water after 3 minutes was measured.

(2) Water absorption (Drip method)
It implemented based on JIS-L-1907. More specifically, one drop of water was dropped onto the surface of the sample with a dropper, and the time until it penetrated the inside and the mirror surface disappeared was measured.

(3) Water content-water absorption after drying (bi-leg method)
It implemented based on JIS-L-1907. More specifically, after repeating the process of immersing the whole sample in water for 30 minutes and air-drying it 5 times, it measured by the same method as said (1).

(4) Water content-Water absorption after drying (Drip method)
It implemented based on JIS-L-1907. More specifically, after repeating the process of immersing the whole sample in water for 30 minutes and air-drying it 5 times, it measured by the same method as said (2).

(5) Dimensional change rate when containing water Measured according to JIS-L-1096. More specifically, the entire 25 cm × 25 cm sample is immersed in water for 10 seconds. Then, the dimension x of one side after removing excess water with a squeezer was measured, and the rate of change (x-25) / 25 with respect to the dimension before immersion was obtained.

(6) Bending softness (texture)
It implemented based on JIS-L-1096. More specifically, the bending resistance when the sample was immersed in water was measured by a 45 ° cantilever method. The evaluation was expressed as “◯” when the bending resistance was 100 mm or more, “Δ” when it was 50 mm or more and less than 100 mm, and “X” when it was less than 50 mm.

(7) Folding suitability Evaluation item a
First, a sample (width 2.54 cm × length 5 cm) is prepared as shown in FIG. Next, as shown in FIG. 3 (2), it is bent in half in the length direction. 3 (2) a is a plan view, and FIG. 3 (2) b is a cross-sectional view (side view). As shown in FIG. 3 (3), an aluminum plate is placed from above in a state where the sample is bent, and then pressure is applied. The pressurizing condition was 5 seconds at 19.6 MPa at room temperature. In the above procedure;
1) The state of FIG. 3 (3) before pressurization was confirmed, and it was determined whether or not an aluminum plate could be installed. When the aluminum plate can be installed, “◯” is indicated, and when the aluminum plate is displaced due to repulsion of the bent portion, “X” is indicated. At this stage, if it was “x”, the subsequent test was discontinued and it was determined as not being qualified.
2) Check the state of Fig. 3 (3) after pressurization, and if the crease is in a straight line and the crease does not open more than 90 ° even after 5 seconds of load release, mark "○" and the state of the crease If the crease opens 90 ° or more when the load is released for 5 seconds or more after the release of the load, “△” is indicated. If the crease is not in a straight line and the load is released for 5 seconds or more, the crease is When it opened 90 degrees or more, it was set as "x" (it was set as "x" also when it repels even if it puts an aluminum plate too hard).
Evaluation item b
A sample (width 2.54 cm × length 5 cm) is prepared as shown in FIG. Next, as shown in FIG. 3 (2), it is bent in half in the length direction. Heat-press in the folded state. The pressurizing condition was 5 seconds at 19.6 MPa at 80 ° C. As shown in FIG. 4, the sample was placed so that the apex was on top (ie, Δ), and the shape after being left for 60 minutes at 20 ° C. and 65% RH was confirmed. If there is almost no change in shape and the degree of sinking of the apex is 20% or less, “○” is indicated. If the degree of sinking of the apex is more than 20% and 50% or less, “△” is indicated, and the degree of apex sinking is 50%. When it exceeded, it was set as "x".
Comprehensive evaluation When both evaluation items a and b are “◯”, it is “4”, when either one is “△”, it is “3”, and when both are “△”, it is “2”. When either one was “x”, it was set to “1”.

<Example 1>
Commercially available products were used as the hygroscopic fibrous material and the shape-retaining fibrous material, respectively. As the shape-retaining fibrous material (shape-retaining layer), PET spunbond “E1012” (manufactured by Asahi Kasei Fibers Co., Ltd., non-woven fabric) was used. Moreover, as a hygroscopic fibrous material (water absorption layer), perforated rayon spunlace “7170A-8P8” (manufactured by Shinwa Co., Ltd., non-woven fabric) was used. In a state where a cobweb-like polyamide hot melt adhesive (weight per unit area: 12 g / m ² ) is interposed between the two materials, it is set in a belt-conveying heat press machine (Carnegiesa roller press machine), at a temperature of 120 ° C. Hot pressing was performed at a pressure of 9.0 N / cm and a heating time of 15 seconds to obtain a laminate composed of a shape retention layer / a water absorption layer / a shape retention layer.

  Subsequently, the laminate was subjected to resin processing. Specifically, the laminate was immersed in a commercially available acrylic resin emulsion “Boncoat ED85E” (manufactured by Dainippon Ink & Chemicals, Inc.) having a solid content concentration of about 45% by weight and impregnated with a resin component ( 1 dip-1 nip system, treatment agent immersion-mangle squeeze, immersion time 3-4 seconds). Then, the said laminated body was taken out and the resin processed body was obtained by performing 110 degreeC * 3 minute (s) drying within a dryer. In the resin processing, a sample of 30 ± 4% by weight (comparative sample) was prepared in addition to a sample of 10 ± 3% by weight (sample of the present invention) as the resin content.

  About the obtained sample, (1) water absorption (bileg method), (2) water absorption (drop method), (3) water absorption-water absorption after drying (bileg method), (4) water absorption-water absorption after drying (5) dimensional change rate when containing water, (6) bending resistance (texture) when containing water, and (7) suitability for crease processing. The results are shown in Table 2.

<Example 2>
A resin processed body was prepared in the same manner as in Example 1 except that PET spunbond “E1030” (manufactured by Asahi Kasei Fibers Co., Ltd., non-woven fabric) was used as the shape-retaining layer, and each physical property was examined. The results are shown in Table 3.

<Example 3>
A resin processed body was prepared in the same manner as in Example 1 except that PET / vinylon resin bond “DF40Z” (manufactured by Kurashiki Fiber Processing Co., Ltd., non-woven fabric) was used as the shape retention layer, and each physical property was examined. The results are shown in Table 4.

<Example 4>
A resin processed body was prepared in the same manner as in Example 1 except that PET “Half Tricot” (manufactured by Ikebu Seisakusho Co., Ltd., knitted fabric) was used as the shape-retaining layer, and each physical property was examined. The results are shown in Table 5.

<Example 5>
A resin processed body was prepared in the same manner as in Example 1 except that nylon spunbond “N5040” (manufactured by Asahi Kasei Fibers Co., Ltd., non-woven fabric) was used as the shape-retaining layer, and each physical property was examined. The results are shown in Table 6.

<Example 6>
A resin processed body was prepared in the same manner as in Example 1 except that rayon spunlace “7180A” (manufactured by Shinwa Co., Ltd., non-woven fabric) was used as the water absorbing layer, and the physical properties were examined. The results are shown in Table 7.

<Example 7>
A resin processed body was prepared in the same manner as in Example 6 except that PET spunbond “E1030” (manufactured by Asahi Kasei Fibers Co., Ltd., non-woven fabric) was used as the shape retention layer, and each physical property was examined. The results are shown in Table 8.

<Example 8>
A resin processed body was prepared in the same manner as in Example 6 except that PET / vinylon resin bond “DF40Z” (manufactured by Kurashiki Fiber Processing Co., Ltd., non-woven fabric) was used as the shape-retaining layer, and each physical property was examined. The results are shown in Table 9.

<Comparative Example 1>
According to Japanese Patent Laid-Open No. 8-318587, a resin processed body was prepared in the same manner as in Example 6 except that the water absorbing layer / shape retaining layer / water absorbing layer was changed, and each physical property was examined. The results are shown in Table 10.

<Comparative Example 2>
A processed resin article was prepared in the same manner as in Comparative Example 1 except that PET spunbond “E1030” (manufactured by Asahi Kasei Fibers Co., Ltd., non-woven fabric) was used as the shape-retaining layer, and each physical property was examined. The results are shown in Table 11.

<Comparative Example 3>
A water-absorbing layer alone was used, and perforated rayon spunlace “7170A-8P8” (made by Shinwa Co., Ltd., non-woven fabric) was used, except that the resin content was only 30% by weight. Each physical property was examined. The results are shown in Table 12.

<Example 9>
A resin processed body was prepared in the same manner as in Example 1 except that a commercially available product was used as the laminate, and each physical property was examined. As the commercially available product, PET / water-absorbing PET laminated spunbond “MA1100” (Asahi Kasei Fibers Co., Ltd., PET fiber / water-absorbing modified PES fiber / PET fiber laminate) was used. The results are shown in Table 13.

<Example 10>
A resin processed body was prepared in the same manner as in Example 1 except that a commercially available product was used as the laminate, and each physical property was examined. As the commercially available product, PET / water-absorbing PET laminated spunbond “MA1300” (Asahi Kasei Fibers Co., Ltd., PET fiber / water-absorbing modified PES fiber / PET fiber laminate) was used. The results are shown in Table 14.

<Example 11>
A resin processed body was prepared in the same manner as in Example 4 except that rayon spunlace “7180A” (manufactured by Shinwa Co., Ltd., non-woven fabric) was used as the water absorbing layer, and each physical property was examined. The results are shown in Table 15.

<Example 12>
A resin processed body was prepared in the same manner as in Example 1 except that a perforated spunlace "PET / Rayon 20/80" (manufactured by Shinwa Co., Ltd., non-woven fabric, 25 mesh) was used as the water absorbing layer. Examined. The results are shown in Table 16.

<Example 13>
A resin processed body was prepared in the same manner as in Example 1 except that perforated spunlace "PET / Rayon 20/80" (manufactured by Shinwa Co., Ltd., non-woven fabric, 22 mesh) was used as the water absorbing layer. Examined. The results are shown in Table 17.

<Example 14>
A resin processed body was prepared in the same manner as in Example 1 except that perforated spunlace “PET / Rayon” (manufactured by Shinwa Co., Ltd., non-woven fabric, 10 mesh) was used as the water-absorbing layer. . The results are shown in Table 18.

<Example 15>
A resin processed body was prepared in the same manner as in Example 12 except that PET spunbond “E1100” (manufactured by Asahi Kasei Fibers Co., Ltd., non-woven fabric) was used as the shape retention layer, and each physical property was examined. The results are shown in Table 19.

  As is clear from the above results, the moisture-absorbing / releasing material (resin content 10 ± 3%) of the present invention is effectively suppressed from decreasing in water absorption over time, and has good shape retention and It can be seen that the crease processing suitability can be exhibited.

<Test Example 1>
Using the laminate (before resin processing) obtained in Example 1, the relationship between the resin content and the water absorption was investigated. As in Example 1, as in Example 1, a commercially available acrylic resin emulsion “Boncoat ED85E” (manufactured by Dainippon Ink & Chemicals, Inc.) having a solid content concentration of about 45% by weight was used. The resin component was impregnated in the same manner as in Example 1 except that the adjustment was performed. The physical properties of the obtained resin processed bodies were examined in the same manner as in Example 1. The results are shown in Table 20.

  As is clear from the results in Table 20, it can be seen that when the resin content exceeds 20% by weight, for example, the water absorption (by leg method) is changed from 104 mm to 68 mm, and the water absorption is greatly reduced with time. In addition, when the resin component is 0% by weight, the water absorption is maintained, but it is disadvantageous in terms of suitability for crease processing. On the other hand, it can be seen that when the resin content is in the range of 2 to 20% by weight, a decrease in water absorption with time can be effectively suppressed and good crease processing suitability can be obtained.

<Test Example 2>
Using the laminate (before resin processing) obtained in Example 1, the relationship between the resin content and the water absorption was investigated. As the resin, a commercially available polyester-based resin emulsion “Vylonal MD1480” (manufactured by Toyobo Co., Ltd.) having a solid content concentration of about 25% by weight was used. In the same manner as in No. 1, the resin component was impregnated. The physical properties of the obtained resin processed bodies were examined in the same manner as in Example 1. The results are shown in Table 21.

  As is clear from the results in Table 21, even when a polyester resin is used, the decrease in water absorption with time is effective as long as the resin content is in the range of 2 to 20% by weight, as in the results in Table 20. It can be seen that good crease processing suitability can be obtained.

Claims (7)

The laminate comprising the water-absorbing fibrous material and the shape-retaining fibrous material laminated on both sides thereof contains 2 to 20 parts by weight of a resin component with respect to 100 parts by weight of the hygroscopic fibrous material. Moisture absorption and desorption material. The moisture-absorbing / releasing material according to claim 1, wherein the water-absorbing fibrous material has one or more through holes penetrating in a tubular shape from one plane to the other plane of the material. The moisture absorbing / releasing material according to claim 2, wherein a ratio of the total area of the through holes on the plane of the water absorbent fibrous material is 20 to 80%. The material for moisture absorption / release according to claim ² , wherein an average area per through hole is 0.5 to ² mm2. The material for moisture absorption / release according to claim 1, wherein the water-absorbing fibrous material is a nonwoven fabric containing rayon fibers. The moisture absorbing / releasing material according to claim 1, wherein the shape-retaining fibrous material is a polyester nonwoven fabric having a structure in which a plurality of long fiber layers having different finenesses are stacked. The moisture absorbing / releasing material according to claim 1, which is used as a moisture absorbing / releasing material for a humidifier.