Dehumidification sheet for bedding

Abstract

To provide a dehumidification sheet 10 for bedding in which humidity is hard to be retained and a use period until a moisture absorption ability is reduced is long.SOLUTION: In the dehumidification sheet 10 for bedding of an embodiment, a dehumidifier 40 is stored in a space S40 between adhesive joint parts 30 provided in a lattice shape in two non-woven cloth sheets 20 having a substantially rectangular shape. A flow path FP is formed between the adhesive joint part and an installation surface. The flow path FP has a length of 185 cm or more, is continuous from one end to the other end, and has openings OP1, OP2 in both ends.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] Embodiments of the present invention relate to a dehumidifying sheet for bedding that is laid under bedding and used.

Background Art

[0002] Japanese Utility Model Registration No. 3185818 discloses a dehumidifying sheet in which lattice-shaped adhesive portions are provided on two non-woven fabric sheets, a space is formed between the adhesive portions, and B-type silica gel particles are accommodated as a dehumidifying agent in the space.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The amount of moisture that a dehumidifying agent can absorb is finite. Therefore, in a dehumidifying sheet for bedding that is laid under bedding and used, if the amount of moisture generated from bedding or the like is too large compared to the amount of moisture that the dehumidifying agent can absorb, the moisture absorption ability will decrease, and the moisture that cannot be absorbed may accumulate under the bedding.

[0005]

[0006] Moreover, when a dehumidifying agent with moisture absorption and desorption properties such as B-type silica gel is used, even if the dehumidifying agent absorbs a large amount of moisture and its moisture absorption ability decreases, the moisture absorption ability can be regenerated by drying the dehumidifying sheet in the sun or the like. However, if the amount of moisture generated from bedding or the like is too large compared to the amount of moisture that the dehumidifying agent can absorb, the moisture absorption ability will decrease in a short period, so frequent drying is required.

Means for Solving the Problems

[0007] The dehumidifying sheet for bedding according to an embodiment of the present invention has a dehumidifying agent accommodated in a space between adhesive portions provided in a lattice pattern in two substantially rectangular sheets, and a length of 185 cm or more is provided between the adhesive portion and the installation surface. A flow path that is continuous from one end to the other end and has openings at both ends is formed.

Advantages of the Invention

[0008] According to an embodiment of the present invention, it is possible to provide a dehumidifying sheet for bedding in which moisture is less likely to accumulate under the bedding and the service life until the moisture absorption ability decreases is long.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Modes for Carrying Out the Invention

[0010] <Embodiment> Hereinafter, the dehumidifying sheet 10 for bedding according to the embodiment (hereinafter referred to as "dehumidifying sheet 10") will be described with reference to the drawings. The drawings are schematic. The relationship between the thickness and width of each part, the ratio of the thickness of each part, and the relative angle are different from the actual ones. There are also parts where the dimensional relationships and ratios are different between the drawings. In addition, the illustration of some components is omitted.

[0011] As shown in FIGS. 1 and 2, the dehumidifying sheet 10 of the embodiment is a substantially rectangular shape with a length L10 of 215 cm and a width W10 of 30 cm. The dehumidifying sheet 10 has an adhesive portion 30, which is a welded portion provided in a lattice pattern, on non-woven sheets 20 (20A, 20B) used as two substantially rectangular breathable sheets. The adhesive portion 30L in the major axis direction LA and the adhesive portion 30S in the minor axis direction SA intersect at the adhesive portion 30X. A space S40 is formed between the lattice-shaped adhesive portions 30.

[0012] For example, in the dehumidifying sheet 10, spaces S40 each having a length L40 of 65 mm and a width W40 of 40 mm are formed 28 in the major axis direction LA and 6 in the minor axis direction SA with an adhesive portion 30 having a width W30 of 12 mm interposed therebetween. The width of the adhesive portion at the peripheral edge is 7 mm.

[0013] The non-woven sheet 20 is manufactured by a spunbond method, a meltblown method, a flash spinning method, a thermal bonding method, a chemical bonding method, a needle punching method, a spunlace method (water jet entanglement method), a stitch bonding method, a steam jet method, or the like. Further, the non-woven sheet 20 may be a single-layer non-woven fabric by the above-described manufacturing method, or may be a laminated non-woven fabric in which a plurality of non-woven fabrics by the same or different manufacturing methods are combined. From the viewpoints of strength and productivity, a non-woven fabric manufactured by the spunbond method is preferable, and further, a laminated non-woven fabric of a non-woven fabric manufactured by the meltblown method composed of ultrafine fibers and a non-woven fabric manufactured by the spunbond method is more preferable from the viewpoint of preventing leakage of fine powder of the dehumidifying agent.

[0014] As the laminated non-woven fabric, a laminated non-woven fabric obtained by laminating a porous film or the like within a range not impairing the breathability may be used. The non-woven sheet 20 may be colored with a pigment or the like, or may have characters or patterns printed thereon. The user can distinguish the dehumidifying sheets used for each of the plurality of futons by using a plurality of dehumidifying sheets of different colors.

[0015] As the material of the nonwoven fabric sheet 20, either synthetic fiber or natural fiber can be used. Examples of synthetic fibers include polyethylene terephthalate, polyester, polypropylene, polyethylene, acrylic, nylon, vinylon, polyvinyl chloride, polyurethane, etc. Examples of natural fibers include cotton, silk, hemp, wool, pulp, etc., and regenerated fibers such as rayon can also be mentioned. In addition, a nonwoven fabric obtained by mixing these natural fibers and synthetic fibers can be used.

[0016] As the material of the nonwoven fabric, core-sheath fibers in which the core part is a high melting point component such as polyester and the sheath part is a low melting point component such as polyethylene, polypropylene, ethylene / propylene copolymer, or copolyester are particularly preferable in terms of high air permeability and good heat sealability.

[0017] For example, the basis weight of the nonwoven fabric sheet 20 is 10 g / m 2 ~150 g / m 2 , and the air permeability measured by the frazil method defined in JIS L 1913:2010 "General Test Methods for Nonwoven Fabrics" is 5 cc / cm 2 ·sec~500 cc / cm 2 ·sec.

[0018] From the viewpoints of air permeability and strength, it is desirable to use the nonwoven fabric sheet 20 for the breathable sheet, but it is not limited thereto as long as it has air permeability and strength. For example, a porous resin film such as a perforated film mechanically perforated with needles or a microporous film having moisture permeability and waterproofness, or paper may be used.

[0019] As shown in FIG. 3, in the space S40 between the two nonwoven fabric sheets 20A and 20B, B-type silica gel, which is a desiccant 40, is accommodated. The height H40 of the space S40 is, for example, 6 mm.

[0020] The two nonwoven fabric sheets 20A and 20B may have different air permeabilities. That is, the lower (floor side) nonwoven fabric sheet 20B may have lower air permeability than the upper (futon side) nonwoven fabric sheet 20A.

[0021] The dehumidifying agent 40 has a function of absorbing moisture in the surroundings to dehumidify. Examples of the dehumidifying agent 40 include type B silica gel, diatomaceous earth, bentonite, sepiolite, activated carbon, activated clay, calcium oxide, zeolite, white carbon, calcium chloride, magnesium chloride, potassium acetate, sodium secondary phosphate, sodium citrate, and water-absorbing polymers. The dehumidifying agent 40 may be used in combination of two or more kinds. As the dehumidifying agent 40, type B silica gel is particularly preferable because it has high moisture absorption and desorption performance, its form does not change before and after moisture absorption and desorption, it has a strength suitable for being laid under a bedding, and it is easily available.

[0022] A known dehumidifying sheet for bedding was designed to fit entirely within the futon 90 when laid under the futon. For this reason, the known dehumidifying sheet only absorbed moisture during use.

[0023] In contrast, as shown in FIG. 4, the length L10 of the dehumidifying sheet 10 is longer than the length L90 of the futon 90 placed on the dehumidifying sheet 10. In other words, the length L10 of the dehumidifying sheet 10 is set such that when laid under the futon 90, both ends thereof protrude from the futon 90.

[0024] In the dehumidifying sheet 10, a flow path FP having openings OP1 and OP2 at both ends protruding from the futon 90 is formed between the adhesive portion 30L in the major axis direction LA and the tatami mat which is the installation surface 100, or a floor surface such as a flooring.

[0025] During use, the dehumidifying sheet 10 not only absorbs moisture emitted from the user (for example, night sweats) and moisture due to condensation, but also releases moisture through the flow path FP. For this reason, the dehumidifying sheet 10 is less likely to trap moisture, and has a long service life until the moisture absorption ability decreases.

[0026] The dehumidifying sheet 10 is particularly effective when the amount of night sweats increases during hot and humid summers, when taking measures against condensation in winter, when the futon cannot be dried in the open air during the rainy season, or when using the futon for a long time such as in nursing care.

[0027] The length L90 of a general futon 90 is, for example, from 180 cm to 210 cm. Therefore, the length L10 in the major axis direction LA of the dehumidifying sheet 10 is preferably 185 cm or more, and particularly preferably more than 210 cm. Considering the position of the coverlet 91 (see FIG. 5) and versatility, the length L10 is, for example, 215 cm. The upper limit of the length L90 is not particularly limited, but considering the length of the long-type futon (L90 = 220 cm), cost, weight, and handleability, it is preferably 255 cm or less, more preferably 245 cm or less, and particularly preferably 230 cm or less.

[0028] If the flow path FP penetrates from one opening OP1 to the other opening OP2, moisture (water vapor), which is a gas, can be released. Therefore, in the present embodiment, the flow path FP has a straight-line shape continuous from one end to the other end of the dehumidifying sheet 10, and the length of the flow path FP continuous from one end to the other end shows the same aspect as the length L10 in the major axis direction LA of the dehumidifying sheet 10, but is not limited thereto. As long as the flow path FP penetrates from one opening OP1 to the other opening OP2, it may be a straight flow path FP that is not parallel to the major axis direction LA, or may have a shape of a straight line or a curve that is refracted in the middle.

[0029] That is, the length of the flow path FP is the same as or longer than the length obtained by connecting one opening OP1 and the other opening OP2 with a straight line. However, from the viewpoint that the shorter the flow path is, the faster the moisture is released, the length of the flow path FP continuous from one end to the other end is preferably the same as the length L10 in the major axis direction LA of the dehumidifying sheet 10.

[0030] Whether the flow path FP penetrates can be confirmed, for example, by irradiating light from one opening OP1 and observing from the other opening OP2. Also, by sending air from one opening OP1, it can be confirmed, by observing the movement of the smoke of an incense stick, that air is being discharged from the other opening OP2. Or, by sucking air from one opening OP1, it can be confirmed, by observing the movement of the smoke of an incense stick, that air is being inhaled from the other opening OP2.

[0031] In addition, in order to efficiently release moisture, the average cross-sectional area of the flow path FP is preferably 4 mm 2 or more. If the cross-sectional area of the flow path FP is too large, unevenness may occur on the futon 90, which may deteriorate the comfort of lying, so the average cross-sectional area of the flow path FP is preferably 200 mm 2 or less. When the cross-sectional area of the flow path FP is not constant, the minimum cross-sectional area of the flow path FP is preferably 2 mm 2 or more, and the maximum cross-sectional area is preferably 350 mm 2 or less.

[0032] As shown in FIGS. 5 and 6, when in use, a load is applied to the dehumidifying sheet 10 by the futon 90, the user 99, and the comforter 91. For this reason, the height H40 of the space S40 decreases. Also, since the bonding portion 30 is pushed downward toward the installation surface 100, the cross-sectional area of the flow path FP becomes smaller.

[0033] In order to ensure that the flow path FP penetrates and the cross-sectional area of the flow path FP is ensured even when a load is applied, in the unloaded state, the height H40 of the space S40 in which the dehumidifying agent 40 is accommodated in the dehumidifying sheet 10 is preferably 1.5 mm or more and 20 mm or less. In order to ensure the height H40 of the space S40, the bulk volume (mm 3 ) of the dehumidifying agent 40 accommodated in the space S40 is preferably 1.5 times or more, more preferably 2 times or more, and particularly preferably 3 times or more the planar area (mm 2 ) of the space S40. The bulk volume (mm 3 ) has no particular upper limit as long as it can fill the space S40, and the planar area (mm 2For example, it is preferably 15 times or less.

[0034] Bulk volume (mm 3 ) is the volume occupied by the particle aggregate in space. The bulk volume of the present invention is the volume measured by putting the desiccant in a measuring cylinder of any capacity, gently tapping it 5 times to level it, and then reading the scale of the measuring cylinder.

[0035] For example, in the dehumidifying sheet 10, the bulk volume of the desiccant 40 (4.6 g of spherical type B silica gel) with a particle size of 2 mm to 4 mm is 12187 mm 3 and is 5 times the planar area 2432 mm of the space S40 2 (= 64 mm × 38 mm). Also, the bulk volume of the desiccant 40 (4.6 g of granular bentonite) with a particle size of 0.5 mm to 1.5 mm is 4769 mm 3 and is 1.5 times the planar area 3024 mm of the space S40 2 (= 56 mm × 54 mm).

[0036] The bulk volume of the desiccant 40 (4.2 g of granular calcium silicate) with a particle size of 5 mm to 6 mm is 27023 mm 3 and is 11 times the planar area 2432 mm of the space S40 2 (= 64 mm × 38 mm).

[0037] Also, the bending stiffness of the bonding portion 30 is preferably 0.003 gf·cm 2 / cm or more. The average inclination (dM / dK) of the bending moment M when a sample (the size can be arbitrarily set in the range of 10 mm to 200 mm in width) is bent in a predetermined curvature range (0.5 cm -1 ~ 1.5 cm -1 ) using an automated pure bending tester (KESFB-2AUTO-A manufactured by Kato Tech Co., Ltd.) is defined as the bending stiffness. The upper limit of the bending stiffness is, for example, 30 gf·cm 2 / cm or less because it is easy to fold the nonwoven fabric sheet 20.

[0038] Factors affecting the bending stiffness of the bonding portion 30 include the basis weight, thickness, material, manufacturing method, etc. of the nonwoven fabric sheet 20. Also, the bending stiffness of the bonding portion 30 can be adjusted by the welding conditions (temperature, pressure, time) of the nonwoven fabric sheets 20A and 20B.

[0039] When the width W30 of the bonding portion 30 increases, even when the same load is applied, the bending of the bonding portion 30 becomes larger. Therefore, (bending stiffness / width of the bonding portion) is preferably 0.05 gf·cm 2 / cm 2 or more.

[0040] For example, in the dehumidifying sheet 10, the bending stiffness of the bonding portion 30 is 1.4 gf·cm 2 / cm, and the width W30 of the bonding portion 30 is 11 mm. Therefore, (bending stiffness / width of the bonding portion) is 1.27 gf·cm 2 / cm 2 . Also, in another example of the dehumidifying sheet 10, the bending stiffness is 0.29 gf·cm 2 / cm, and the width W30 of the bonding portion 30 is 1.1 mm. Therefore, (bending stiffness / width of the bonding portion) is 2.6 gf·cm 2 / cm 2 . Further, in another example of the dehumidifying sheet 10, the bending stiffness is 0.29 gf·cm 2 / cm, and the width W30 of the bonding portion 30 is 50 mm. Therefore, (bending stiffness / width of the bonding portion) is 0.058 gf·cm 2 / cm 2 .

[0041] The dehumidifying sheet 10 is manufactured by enclosing the dehumidifying agent 40 while welding two nonwoven fabric sheets 20A and 20B containing a thermoplastic resin. The welded portion becomes the bonding portion 30. Note that as long as a predetermined bending stiffness can be ensured, the bonding portion may be a bonding portion using an adhesive or a stitched bonding portion.

[0042] The flow path FP formed by the adhesive portions 30L in the long axis direction LA is composed of adhesive portions 30L in the long axis direction and adhesive portions 30X in the intersection regions. Since adhesive portions 30X in the intersection regions where adhesive portions 30L in the long axis direction and adhesive portions 30S in the short axis direction intersect are crimped twice, their bending stiffness is equal to or greater than that of adhesive portions 30L and 30S.

[0043] It goes without saying that short flow paths are also formed by the adhesive portions 30S in the minor axis direction. However, because the flow paths in the minor axis direction are completely covered by the mattress 90, they do not provide breathability during use. A dehumidifying sheet 10 whose width W10 is wider than the width of the mattress 90 is preferable because it can ensure breathability in the flow paths in the minor axis direction as well. A wide dehumidifying sheet 10 can ensure breathability if the flow paths are wider than the mattress 90 in both the minor axis direction and the major axis direction of the mattress 90.

[0044] From the viewpoints of cost and weight, the width of the dehumidifying sheet 10 in the minor axis direction is preferably 75 cm or less, more preferably 50 cm or less, and particularly preferably 40 cm or less. Furthermore, from the viewpoint of ensuring a sufficient cross-sectional area of the flow path FP, the width of the dehumidifying sheet 10 in the minor axis direction is preferably 10 cm or more.

[0045] It is preferable that the dehumidifying sheet 10 be provided with an indicator that shows a decrease in the moisture absorption capacity of the dehumidifying agent. For example, indicator beads made by mixing cobalt chloride with silica gel and that are blue in the dry state and turn pink when they absorb moisture from the atmosphere may be housed together with the dehumidifying agent, or humidity detection paper impregnated with a cobalt chloride solution that changes color depending on the amount of moisture absorbed by the dehumidifying agent may be disposed on the outer surface of the dehumidifying sheet 10.

[0046] <Modification> The dehumidifying sheets 10A and 10B of the modified examples are similar to and have the same functions as the dehumidifying sheet 10. Therefore, in the following description, components having the same functions as the dehumidifying sheet 10 are denoted by the same reference numerals as the dehumidifying sheet 10, and descriptions thereof will be omitted.

[0047] <Variation 1> In the dehumidifying sheet 10A of this modification example, the planar shape of the space S40 is circular.

[0048] In the above-described embodiment, the planar shape of the space S40 formed by the adhesive portions 30 provided in a lattice shape is rectangular, that is, an aspect in which the planar shape of the space S40 and all of the adhesive portions 30 are composed of straight lines was shown.

[0049] However, the embodiment is not limited to this. For example, as the adhesive portion 30S, it has only the adhesive portions at the peripheral portions in the short-axis direction SA, and an adhesive portion 30X where the adhesive portion 30L in the long-axis direction and the adhesive portion 30S in the short-axis direction intersect is arranged only at both ends in the long-axis direction LA of the dehumidifying sheet 10. That is, a mode in which the space S40 having an elongated shape in the long-axis direction LA is arranged in a plurality in the short-axis direction SA may be used.

[0050] As long as the adhesive portion 30L in the long-axis direction and the adhesive portion 30S in the short-axis direction are arranged so as to intersect at 30X, and a flow path FP having a length of 185 cm or more and continuous from one end to the other end and having openings at both ends can be formed by the adhesive portion 30L in the long-axis direction, the planar shape of the space S40 may be a shape including a curve, regardless of whether it is rectangular.

[0051] <Modification Example 2> In the dehumidifying sheet 10B of this modification example, the adhesive portion 30L in the long-axis direction LA includes a strip-shaped body separate from the nonwoven fabric sheet 20 as a reinforcing member for the adhesive portion 30L. The strip-shaped body is made of, for example, a resin sheet fixed to the upper surface of the adhesive portion 30L. The bending stiffness of the adhesive portion is increased by the separate strip-shaped body, and the flow path FP can be ensured even when the bending stiffness is insufficient with only the nonwoven fabric sheet.

[0052] The reinforcing member may be a molded resin as long as it does not impair the air permeability, or a thermosetting resin may be applied to the surface of the adhesive portion. Further, the reinforcing member may be an adhesive applied to the inner surface of the adhesive portions of the nonwoven fabric sheets 20A and 20B.

[0053] Note that the bedding for which the dehumidifying sheet 10 is used is not limited to the futon 90, and it may be a bed pad, a mattress, or the like.

[0054] In the space S40 of the dehumidifying sheet 10, in addition to the dehumidifying agent 40, another functional preparation (for example, a deodorant, a deodorizer, an aromatic agent, a far-infrared ray emitting agent, an insect repellent, an acaricide, an antifungal agent, a bactericide, a gelling agent) may be included.

[0055] The dehumidifying sheet 10 may be manufactured by welding a plurality of cylindrical ventilation members in which the dehumidifying agent 40 is enclosed. In addition, in the above-described embodiment, an example of welding two non-woven fabric sheets 20A and 20B has been described, but 20A and 20B do not necessarily have to be separate sheets. For example, one side of a single folded non-woven fabric sheet may be used as the non-woven fabric sheet 20A and the other side may be used as the non-woven fabric sheet 20B.

[0056] Instead of the two non-woven fabric sheets 20A and 20B, the dehumidifying sheet 10 may use a microporous film having moisture permeability and waterproofness, and may contain a gelling agent together with a deliquescent salt such as calcium chloride as the dehumidifying agent 40.

[0057] The present invention is not limited to the above-described embodiments and the like. The present invention can be variously modified, changed, and combined with components without departing from the gist of the present invention.

Explanation of Reference Numerals

[0058] 10, 10A, 10B... Dehumidifying sheet for bedding 20, 20A, 20B... Non-woven fabric sheet 30, 30L, 30S, 30X... Adhesive part 40... Dehumidifying agent 90... Futon 91... Quilt 99... User 100... Installation surface

Claims

1. A desiccant is accommodated in a space between adhesive portions provided in a lattice pattern in two substantially rectangular breathable sheets, A dehumidifying sheet for bedding, characterized in that a flow path having a length of 185 cm or more, continuous from one end to the other end, and having openings at both ends is formed between the adhesive portion and the installation surface.

2. The bulk volume (mm 3 ) of the dehumidifying agent accommodated in the space is ２ 1.5 times or more the planar area (mm ２ ) of the space, and the dehumidifying sheet for bedding according to claim 1 is characterized by this.

3. The dehumidifying sheet for bedding according to claim 1, wherein the height of the space in which the desiccant is accommodated is 1.5 mm or more and 20 mm or less.

4. The bending stiffness of the bonding part is 0.003 gf·cm ２ / cm or more, and the dehumidifying sheet for bedding according to claim 1, characterized in that.

5. The dehumidifying sheet for bedding according to claim 1, wherein the width of the adhesive portion is 0.1 cm or more and 5 cm or less.

6. (The bending stiffness of the bonding part / the width of the bonding part) is 0.05 gf·cm ２ / cm ２ The dehumidifying sheet for bedding according to claim 1, characterized in that it is 0.05 gf·cm / cm or more.

7. The cross-sectional area of the flow path is 2 mm ２ or more and 350 mm ２ or less, and the dehumidifying sheet for bedding according to claim 1, characterized in that it is as described above.

8. The dehumidifying sheet for bedding according to claim 1, wherein the adhesive portion includes a strip separate from the breathable sheet.

9. The breathable sheet is a nonwoven fabric sheet containing a thermoplastic resin, The dehumidifying sheet for bedding according to claim 1, wherein the adhesive portion is a welded portion of the nonwoven fabric sheet.

10. The dehumidifying sheet for bedding according to claim 1, wherein the desiccant is type B silica gel.

11. The dehumidifying sheet for bedding according to claim 1, further comprising an indicator indicating a decrease in the moisture absorption capacity of the desiccant.

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