Heating devices

Abstract

To provide a heating device that has a low risk of burns and can provide sufficient heat. [Solution] The heating device 1 comprises a plurality of silica gel particles 3 and a breathable storage section 2 formed in the shape of a bag with a space inside for housing the plurality of silica gel particles 3. The ratio of the surface area of ​​the storage section 2 to the volume of the plurality of silica gel particles 3 sealed in the storage section 2 is 130% or more and 160% or less.

Description

[Technical Field]

[0001] This disclosure relates to a heating device. [Background technology]

[0002] Applying heat to specific parts of the body has long been used to alleviate pain, relieve stiffness, soothe fatigue, and reduce irritability and stress through the relaxing effects of heat. For example, menstrual cramps, a symptom unique to women, mainly involve a combination of lower abdominal and lower back pain. Applying a heating device to the abdomen or lower back to apply heat to the affected area is effective in relieving the pain. Similarly, applying a heating device to the affected area to alleviate the symptoms of PMS (premenstrual syndrome) before menstruation is effective in reducing pain and suppressing irritability.

[0003] As a heat-relieving device, chemical hand warmers, also known as disposable hand warmers, are frequently used. These warmers consist of a breathable, bag-like container filled with a powdered heat-generating composition that generates heat upon contact with air. However, chemical hand warmers have drawbacks: they require the bag to be shaken several times to efficiently bring the heat-generating composition into contact with air, which is time-consuming; and they take a long time to generate heat, meaning they cannot be used immediately.

[0004] Therefore, a heating device is used that can provide heat by heating it for a short time, for example, in a microwave oven. This heating device has silica gel sealed in a breathable bag-shaped container. The silica gel adsorbs water vapor contained in the atmosphere, and when the water vapor adsorbed by the silica gel is heated, the heating device can provide heat to the affected area with the heat of the heated water vapor (see, for example, Patent Document 1). [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2000-139987 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] The thermal effect of heat therapy devices using silica gel varies greatly depending on the size of the container and the amount of silica gel used. For example, if the temperature becomes too high, there is a risk of burns when using the heat therapy device. Conversely, if the temperature is too low, sufficient heat cannot be delivered to the affected area, reducing the therapeutic effect of the heat therapy device.

[0007] Therefore, one of the objectives of this disclosure is to provide a heating device that has a low risk of burns and can provide sufficient heat, in order to solve the aforementioned problems. [Means for solving the problem]

[0008] A heating device according to a first aspect of the present disclosure comprises a plurality of silica gel particles and a breathable storage portion formed in the shape of a bag having a space inside for housing the plurality of silica gel particles, wherein the ratio of the surface area of ​​the storage portion to the volume of the plurality of silica gel particles sealed in the storage portion is 130% or more and 160% or less.

[0009] As a heating device according to a second aspect of this disclosure, the heating device according to the first aspect described above has a compression work rate of 125 gf·cm / cm in the direction perpendicular to the bottom surface applied to the body. 2 It may be structured as described above.

[0010] As a heating device according to a third aspect of this disclosure, the heating device according to the first or second aspect described above may be configured such that the particle size is 5.0 mm or less.

[0011] As a warming device according to the fourth aspect of the present disclosure, the warming device according to any one of the first to third aspects described above may be configured such that the housing portion is formed in a bag shape by joining a first sheet and a second sheet at an outer peripheral portion, and the stretchability of the second sheet is greater than that of the first sheet.

[0012] As a warming device according to the fifth aspect of the present disclosure, the warming device according to any one of the first to fourth aspects described above may be configured such that the shape as viewed along a direction orthogonal to the bottom surface is a circle with a diameter of 90 mm or more and 110 mm or less.

Advantages of the Invention

[0013] According to the warming device according to the present disclosure, the risk of burns is low and sufficient warming can be provided.

Brief Description of the Drawings

[0014] [Figure 1] FIG. 1 is a perspective view of the warming device. [Figure 2] FIG. 2 is a plan view of the warming device. [Figure 3] FIG. 3 is a bottom view of the warming device. [Figure 4] FIG. 4 is a side view of the warming device. [Figure 5] FIG. 5 is a cross-sectional view of the warming device. [Figure 6] FIG. 6 is a view showing the top surface, bottom surface, and side surface of the warming device. [Figure 7] FIGS. 7(A) and (B) are schematic views of the arrangement of a plurality of silica gel particles in the housing portion.

Embodiments for Carrying Out the Invention

[0015] Specific embodiments of the warming device according to the present disclosure will be described while referring to the drawings. The same or corresponding parts in the drawings are denoted by the same reference numerals, and the description thereof will not be repeated.

[0016] <Overview of the Warming Device> Figures 1 to 5 are perspective views, top views, bottom views, side views, and cross-sectional views of a heating device 1 according to one embodiment of the present disclosure. The heating device 1 is used by applying it to a predetermined part of the user's body, and by applying heat to the predetermined part, it can relieve pain, loosen stiffness, and soothe fatigue. In addition, the relaxing effect of heat can reduce stress and irritability. The heating device 1 is not particularly limited, but it is suitably used for menstrual cramps and premenstrual syndrome (PMS) symptoms, and applying the heating device 1 to the abdomen or lower back to apply heat is effective in relieving pain and suppressing irritability.

[0017] The heating device 1 comprises a bag-shaped containment section 2 and a plurality of silica gel particles 3 (hereinafter referred to as "silica gel particles 3") sealed in the containment section 2 as a heat-generating material. The heating device 1 is used after being heated by an external heating device such as a microwave oven. Since the silica gel particles 3 sealed in the containment section 2 adsorb water vapor contained in the air, when the heating device 1 is heated, for example in a microwave oven, the water vapor adsorbed by the silica gel particles 3 is heated and becomes warm water vapor (hereinafter referred to as "warm steam"). The heat from this warm steam allows the heating device 1 to provide heat to the affected area.

[0018] The heat from steam is moist heat, which contains moisture, and therefore has higher thermal conductivity compared to dry heat, such as the heat emitted from chemical hand warmers, which does not contain moisture. As a result, the heat penetrates not only the surface of the body but also deep into the tissues, allowing the heat device 1 to effectively deliver heat to the body.

[0019] Furthermore, even after releasing water vapor, the silica gel particles 3 can re-adsorb water vapor from the air after a predetermined period of time. Therefore, the heating device 1 can be used repeatedly.

[0020] The heating device 1 has a flattened shape. Therefore, referring to Figure 6, when the heating device 1 is placed on a horizontal surface 9 such as the top surface of a stand, the size in the thickness direction perpendicular to the horizontal surface 9 (thickness) is significantly smaller than the size in the vertical and horizontal directions parallel to the horizontal surface. The thickness T of the heating device 1 is not particularly limited, but is, for example, 10 mm or more and 60 mm or less. The thickness T of the heating device 1 refers to the vertical distance between the top surface 4 of the heating device 1 that is in contact with the plate 10 and the bottom surface 5 of the heating device 1 that is in contact with the horizontal surface 9, when the heating device 1 is placed on the horizontal surface 9 and then pressed down by placing a pair of transparent plates 10, such as acrylic plates, which have parallel main surfaces spaced apart in the thickness direction. The weight of the plate 10 is approximately 50 g.

[0021] Referring to Figure 2, the shape of the heating device 1 as viewed along the direction parallel to its thickness (hereinafter referred to as the "plan view shape") is not particularly limited, but can be various shapes such as circles, ellipses, polygons (e.g., squares), as well as heart shapes, star shapes, ring shapes, etc. Furthermore, the plan view shape of the heating device 1 may be a horizontally elongated shape where the vertical length is significantly greater than the horizontal length. To make it easier to apply the heating device 1 to the user's abdomen or waist, the plan view shape of the heating device 1 is preferably circular or square, and in that case, to make it easier to grasp the heating device 1, the plan view shape of the heating device 1 is preferably circular.

[0022] The dimensions of the heating device 1 in the vertical and horizontal directions parallel to its thickness are not particularly limited, but are preferably 90 mm to 110 mm in order to apply heat to an appropriate area of ​​the user's abdomen and waist and to make the heating device 1 easy to grasp. If the plan view shape of the heating device 1 is, for example, circular, then the diameter is 90 mm to 110 mm.

[0023] [Description of the accommodation area] Referring to Figure 5, the containment section 2 is formed in a bag shape so as to have a space inside for containing a plurality of silica gel particles 3. In this embodiment, the containment section 2 has one space inside, but it may be divided into multiple spaces. The containment section 2 includes a first sheet 7 and a second sheet 8 facing each other along the thickness direction of the heating device 1. The containment section 2 can be formed in a bag shape by, for example, overlapping the first sheet 7 and the second sheet 8 and joining their outer peripheries. For joining the first sheet 7 and the second sheet 8, for example, sutures can be used, but adhesive or heat sealing may also be used.

[0024] The first sheet 7 and the second sheet 8 are flexible and can be formed from, for example, woven fabrics, nonwoven fabrics, or knitted fabrics. The first sheet 7 and the second sheet 8 can be formed using, for example, natural fibers such as cotton; semi-synthetic fibers such as rayon; synthetic fibers such as polypropylene, polyethylene, polyester, and polyurethane; and blended fibers made by mixing various fibers.

[0025] The first sheet 7 is the sheet that comes into contact with the user's body when using the heating device 1. Referring to Figure 6, the first sheet 7 includes the bottom surface 5 of the heating device 1 that comes into contact with the body. In the first sheet 7, the central portion, excluding the part near the outer edge, becomes the bottom surface 5 of the heating device 1. The first sheet 7 is preferably made of polyester in order to provide a good feel against the skin when the heating device 1 is applied to the user's body and to retain heat without letting it escape to the outside. Furthermore, the first sheet 7 is more preferably napped in order to provide a good feel against the skin.

[0026] The second sheet 8 is the sheet on the side opposite to the side that is applied to the user's body when using the heating device 1, and is the side that the user grasps. Referring to Figure 6, the second sheet 8 includes the upper surface 4 of the heating device 1. In the second sheet 8, the portion excluding the part near the outer edge becomes the upper surface 4 of the heating device 1. The second sheet 8 is preferably formed using a blended fiber of polyester mixed with highly elastic polyurethane, as this allows for good durability when using the heating device 1, excellent quick-drying properties, excellent elasticity, and the ability to retain heat without letting it escape to the outside.

[0027] The basis weight of the first sheet 7 and the second sheet 8 is not particularly limited, but for example, 150 g / m² 2 More than 300g / m 2 The following is the preferred basis weight for the first sheet 7: 230 g / m². 2 Therefore, the preferred basis weight of the second sheet 8 is 190 g / m². 2 That is the case.

[0028] The elasticity of the second sheet 8 is not particularly limited, but it is preferable that it is greater than that of the first sheet 7. By increasing the elasticity of the second sheet 8, when the heating device 1 is grasped by the second sheet 8 and applied to the user's body, the heating device 1 will fit more easily to the user's hand. In addition, when filling the containment section 2 with silica gel particles 3, using the highly elastic second sheet 8 makes the filling process easier.

[0029] <Explanation of silica gel particles> Silica gel particles 3 are granular silica gel commonly used as a desiccant. Silica gel comes in two types: Type A, which exhibits high dehumidifying power at low humidity, and Type B, which exhibits high dehumidifying power at high humidity. Type A silica gel efficiently adsorbs water vapor from the air even at low humidity and releases the adsorbed water vapor when heated. Therefore, it is preferable to use Type A silica gel for silica gel particles 3, as it readily adsorbs water vapor from the air in everyday indoor environments.

[0030] Referring to Figure 5, the shape of the silica gel particles 3 is not particularly limited, but is preferably spherical or nearly spherical. The spherical or nearly spherical shape of the silica gel particles 3 allows the user to feel a smooth and supple sensation when the heating device 1 is applied to their body. It is preferable that all of the silica gel particles 3 sealed in the containment section 2 are spherical or nearly spherical, but it is acceptable for some of the silica gel particles 3 to have irregular shapes. For example, even if 10% or less of the total number of silica gel particles 3 sealed in the containment section 2 are not spherical or nearly spherical, a good sensation can still be transmitted to the user when the heating device 1 is applied to their body.

[0031] The particle size of the silica gel particles 3 is, for example, 2.0 mm to 5.0 mm, and is not particularly limited, but is preferably 2.0 mm to 4.0 mm. If the particle size of the silica gel particles 3 is large, when the heating device 1 is applied to the user's body, it will convey a rough, hard feeling rather than a smooth and supple feel to the user. If the particle size of the silica gel particles 3 is small, the silica gel particles 3 may fall out of the storage section 2 through the seams. For this reason, it is preferable that the particle size of the silica gel particles 3 is 2.0 mm to 4.0 mm.

[0032] The particle size of the silica gel particles 3 can be measured, for example, by clamping the silica gel particles 3 with calipers. Preferably, all of the silica gel particles 3 sealed in the containment section 2 have a particle size of 2.0 mm to 4.0 mm, but it is acceptable for some of the silica gel particles 3 to have a particle size outside the range of 2.0 mm to 4.0 mm. For example, even if 10% or less of the total number of silica gel particles 3 sealed in the containment section 2 have a particle size outside the range of 2.0 mm to 4.0 mm, a good sensation can still be transmitted to the user when the heating device 1 is applied to the user's body.

[0033] The amount of silica gel particles 3 to be filled is, for example, 100 ml to 300 ml, and is not particularly limited, but is preferably 160 ml to 200 ml. The amount of silica gel particles 3 to be filled can be measured, for example, using a graduated cylinder. A plurality of silica gel particles 3 sealed in the containment section 2 are placed in a graduated cylinder and, for example, placed on a horizontal surface, and the scale is read. This measures the amount of silica gel particles 3 to be filled.

[0034] [Surface contact rate of silica gel particles] The heating device 1 generates moist heat when multiple silica gel particles 3 sealed in the containment section 2 are irradiated with microwaves, for example, in a microwave oven, causing the temperature to rise. Therefore, if microwaves are irradiated unevenly to only some of the multiple silica gel particles 3 sealed in the containment section 2, the heating device 1 will not heat up easily and its temperature will not rise properly. On the other hand, if microwaves are irradiated evenly to the multiple silica gel particles 3 sealed in the containment section 2, the heating device 1 will heat up efficiently and reach a high temperature. However, if the heating device 1 heats up excessively, its temperature will become too high.

[0035] Referring to Figure 7, of the multiple silica gel particles 3 sealed in the containment section 2, the multiple silica gel particles 30 located on the front side that are in contact with the containment section 2 are easily exposed to microwave irradiation, while the multiple silica gel particles 31 located on the inside (middle) surrounded by the multiple silica gel particles 30 on the front side are less exposed to microwave irradiation. Therefore, referring to Figure 7(A), if there are many multiple silica gel particles 30 located on the front side that are easily exposed to microwave irradiation among the multiple silica gel particles 3 sealed in the containment section 2, the heating device 1 will heat up efficiently and easily reach a high temperature. This makes it possible to apply sufficient heat to the affected area with the heating device 1. However, if there are too many multiple silica gel particles 30 located on the front side, the heating device 1 will overheat and its temperature will become too high, posing a risk of burns to the user when using the heating device 1. On the other hand, referring to Figure 7(B), if there are few multiple silica gel particles 30 located on the front side and many multiple silica gel particles 31 located on the inside, the heating device 1 will not heat up easily and its temperature will not rise sufficiently. Therefore, the heating device 1 cannot provide sufficient heat to the affected area.

[0036] Thus, the temperature characteristics of the heating device 1 vary greatly depending on the size of the containment section 2 and the amount of silica gel particles 3 filled in it. Unless an appropriate amount of silica gel particles 3 is sealed in the containment section 2 according to its size, it is not possible to provide sufficient heat while suppressing the occurrence of burns. Therefore, in this disclosure, the surface contact rate of the silica gel particles 3 is defined as a parameter, and by adjusting the ratio of multiple silica gel particles 30 located on the front side that is easily exposed to microwave irradiation within the containment section 2, the temperature characteristics of the heating device 1 are appropriately controlled, making it possible to provide sufficient heat with the heating device 1 while reducing the risk of burns when using the heating device 1.

[0037] The surface contact rate of the silica gel particles 3 described above is the ratio of the surface area S of the containment section 2 to the volume V of the multiple silica gel particles 3 enclosed in the containment section 2 (the amount of silica gel particles 3 packed in the containment section 2), and is calculated as S ÷ V × 100 (%).

[0038] The surface area S of the housing section 2 is calculated by the following method. Referring to Figure 6, the heating device 1 is placed on the horizontal surface 9 with the first sheet 7 facing downwards, and then a transparent plate 10 is placed on the second sheet 8 of the heating device 1 to hold it down. The part in contact with the plate 10 is defined as the top surface 4 of the heating device 1, the part in contact with the horizontal surface 9 is defined as the bottom surface 5 of the heating device 1, and the surface between the top surface 4 and the bottom surface 5 is defined as the side surface 6 of the heating device 1. The areas S1 of the top surface 4, S2 of the bottom surface 5, and S3 of the side surface 6 are determined and added together. Thus, the surface area S = S1 + S2 + S3 of the housing section 2 is calculated. In this embodiment, since the plan view shape of the heating device 1 is circular, the shapes of the top surface 4 and the bottom surface 5 are circular. Therefore, in this embodiment, the area S1 of the top surface 4 and the area S2 of the bottom surface 5 are both determined by measuring their respective radii and calculating radius × radius × π(3.14). Furthermore, the area S3 of the side surface 6 of the heating device 1 is determined by the product of the circumference of the side surface 6 and the thickness T of the heating device 1, and the circumference of the side surface 6 is approximated by the circumference of the base surface 5. Therefore, in this embodiment, the area of ​​the side surface 6 is determined by the product of the circumference of the base surface 5 (diameter × π(3.14)) and the thickness T of the heating device 1.

[0039] As described above, the surface contact rate of the silica gel particles 3 is between 130% and 160%, which allows for appropriate control of the temperature characteristics of the heating device 1. This reduces the risk of burns when using the heating device 1 while still providing sufficient heat.

[0040] The temperature characteristics of the heating device 1 are such that the maximum surface temperature in a 20°C environment is not particularly limited, but is preferably between 40°C and 70°C, and more preferably between 50°C and 65°C. When the maximum surface temperature of the heating device 1 is between 40°C and 70°C, it can provide comfortable warmth to the body without being too hot or not hot enough.

[0041] The duration for which the surface temperature of the heating device 1 reaches 40°C or higher in a 20°C environment is preferably 25 minutes or more, and more preferably 30 minutes or more. A duration of 25 minutes or more of 40°C or higher for the heating device 1 provides the body with sufficiently long-lasting heat that is effective in relieving pain and irritation in the affected area.

[0042] The surface temperature of the heating device 1 can be measured by the following procedure. First, the heating device 1 is placed in an environment with a temperature of 20°C and a humidity of 60% for at least 4 hours to allow it to acclimate, thereby maintaining a constant temperature and humidity for the silica gel particles 3. Next, the temperature sensor is attached to the polystyrene foam board using surgical tape or similar. Then, the heating device 1 is heated, for example, in a microwave oven, and afterwards, the heating device 1 is placed on the temperature sensor and the surface temperature of the heating device 1 is measured.

[0043] The time it takes for the heating device 1 to reach the above-mentioned maximum surface temperature is not particularly limited, but it is preferably 6 minutes or less, and more preferably 4 minutes or less, when heated in a microwave oven with an output of 600W. This allows the heating device 1 to be used after a short heating time, so it can be used immediately when needed.

[0044] [Compression characteristics of heating devices] When silica gel particles 3, in a volume equal to or close to the internal volume of the storage section 2, are completely filled into the storage section 2, the silica gel particles 3 become less likely to move within the storage section 2. Therefore, even if a compressive load is applied to the heating device 1, the heating device 1 is less likely to deform. In contrast, when silica gel particles 3, in a volume less than the internal volume of the storage section 2, are filled into the storage section 2 with some leeway, the silica gel particles 3 move more easily within the storage section 2. Therefore, the heating device 1 is more likely to deform when a compressive load is applied to it. Because the heating device 1 is easily deformable, it can be applied to various parts of the body with different shapes with good fit, thus providing a good sensation to the user when the heating device 1 is applied to their body.

[0045] As the compression characteristics of the heating device 1, the compression work amount (WC) of the KES compression testing machine in the direction orthogonal to the bottom surface 5 (thickness direction) is not particularly limited, but is preferably 125 gf·cm / cm 2 or more, more preferably 135 gf·cm / cm 2 or more, still more preferably 150 gf·cm / cm 2 or more, still more preferably 165 gf·cm / cm 2 or more. Note that if the compression work amount (WC) is too large, the thickness of the heating device 1 will increase, and the shape retention of the heating device 1 may deteriorate, resulting in poor fit. Therefore, the compression work amount (WC) is preferably 400 gf·cm / cm 2 or less.

[0046] The compression work amount (WC) can be measured by the following method. Using a compression testing machine (KES-G5 manufactured by Kato Tech Co., Ltd.), place the heating device 1 on the table so that the thickness direction is orthogonal to the upper surface of the table, and contact a terminal (contact area: 2.0 cm 2 ) with the central part of the upper surface 4 of the heating device 1. Then, lower the terminal at a speed of 1 mm / sec, and measure the compression work amount (WC) when the heating device 1 is compressed by the terminal until a load of 250 gf / cm 2 is applied. Note that the thickness of the heating device 1 when a load of 0.5 gf / cm 2 is applied is taken as the initial thickness, and the thickness of the heating device 1 when a load of 250 gf / cm 2 is applied is taken as the thickness at the time of load.

[0047] When the above-described compression work amount (WC) is 125 gf·cm / cm 2 or more and 400 gf·cm / cm 2 or less, the heating device 1 can be applied to various parts of the body with different shapes with good fit, and when the heating device 1 is applied to the user's body, a good feeling can be transmitted to the user.

[0048] [Functions and Effects of the Heating Device] The heating device 1 according to the above embodiment is characterized in that the ratio of the surface area S of the containment part 2 to the volume V of the plurality of silica gel particles 3 enclosed in the containment part 2 is 130% or more and 160% or less. This allows for appropriate control of the temperature characteristics of the heating device 1, thereby reducing the risk of burns when using the heating device 1 while providing sufficient heat.

[0049] Furthermore, the heating device 1 according to the above embodiment has a compression work (WC) of 125 gf·cm / cm² in the direction perpendicular to the bottom surface 5 that is applied to the body. 2 The above features allow the heating device 1 to be applied to various parts of the body with different shapes with good fit, and a pleasant sensation can be transmitted to the user when the heating device 1 is applied to the user's body.

[0050] Furthermore, the heating device 1 according to the above embodiment is characterized in that the particle size of the silica gel particles 3 is 4 mm or less. This allows for a pleasant sensation to be transmitted to the user when the heating device 1 is applied to the user's body.

[0051] Furthermore, the heating device 1 according to the above embodiment is characterized in that the storage section 2 is formed in a bag shape by joining the first sheet 7 and the second sheet 8 at their outer circumference, and the second sheet 8 has greater elasticity than the first sheet 7. As a result, the heating device 1 fits more easily to the user's hand. In addition, by using the highly elastic second sheet 8 when filling the storage section 2 with silica gel particles 3, the filling work of silica gel particles 3 can be made easier.

[0052] Furthermore, the heating device 1 according to the above embodiment is characterized in that its shape, when viewed along a direction perpendicular to the bottom surface 5, is circular with a diameter of 90 mm to 110 mm. This makes the heating device 1 easy to grasp by hand and easy to apply to the user's abdomen or lower back.

[0053] [Differentiation] Although a heating device 1 according to one embodiment of this disclosure has been described, the heating device 1 according to the above embodiment can be modified in various ways without departing from the spirit of this disclosure.

[0054] [Examples] The operation and effects of the heat therapy devices of this disclosure will be explained below with reference to examples and comparative examples. However, the heat therapy devices of this disclosure are not limited to the following examples.

[0055] Similar to the heating devices according to the embodiments shown in Figures 1 to 5 above, a heating device was prepared by enclosing multiple silica gel particles in a storage compartment formed in a bag shape using the first and second sheets. For each example, the surface area of ​​the storage compartment, the bottom area of ​​the heating device, the thickness of the heating device, the amount of silica gel particles filled, and the surface contact rate of the silica gel particles are as shown in Table 1.

[0056] For each example of a heating device, the maximum surface temperature of the device in a 20°C environment after heating in a 600W microwave oven for 30 seconds, and the duration for which the surface temperature of the heating device remained above 40°C in a 20°C environment were measured. The measurement results are shown in Table 1. In addition, for each example of a heating device, sensory evaluations 1 and 2 regarding the warming effect were performed by applying the heated heating device to the subject's body. Sensory evaluation 1 evaluated the warmth 5 minutes after the start of use of the heating device on a four-point scale: "hot," "comfortable," "somewhat comfortable," and "not enough." Sensory evaluation 2 evaluated the duration of warmth on a two-point scale: "satisfactory" and "dissatisfactory." The evaluation results are shown in Table 1.

[0057] For each example of a heating device, the work of compression (WC) and the difference between the thickness under load and the initial thickness were measured. The measurement results are shown in Table 1. In addition, for each example of a heating device, a sensory evaluation 3 was conducted regarding the fit when the heating device was applied to the subject's body. Sensory evaluation 3 was evaluated on a four-point scale: "satisfied," "somewhat satisfied," "neither satisfied nor dissatisfied," and "dissatisfied." The evaluation results are shown in Table 1.

[0058] [Table 1]

[0059] Comparing Examples 1 to 3 with Comparative Examples 1 to 3, it can be confirmed that the surface contact rate of the multiple silica gel particles enclosed in the containment section is 130% to 160%, thereby reducing the risk of burns when using the heating device and allowing the heating device to provide sufficient heat.

[0060] Furthermore, for the heating devices of Examples 1 to 3 and Comparative Example 1, a sensory evaluation was conducted on 12 subjects with symptoms of menstrual cramps or PMS, in which they applied the heating devices to their abdomen for 20 minutes to assess whether their symptoms were alleviated. The results are shown in Tables 2 and 3. According to Tables 2 and 3, it was confirmed that the use of the heating devices of Examples 1 to 3 could alleviate symptoms of menstrual cramps and PMS.

[0061] [Table 2]

[0062] [Table 3]

[0063] Furthermore, comparing Examples 1 to 3 and Comparative Example 3 with Comparative Examples 1 to 2, the compression work of the heating device was 125 gf·cm / cm². 2 Based on the above, it is confirmed that the heating device can be applied to the body in a way that provides a good fit. Therefore, it can be seen that when the heating device is applied to the user's body, it can transmit a pleasant sensation to the user.

[0064] The embodiments and examples disclosed herein are illustrative in all respects and should be understood not to be restrictive in any way. The scope of the invention is defined by the claims rather than the foregoing description, and all modifications within the meaning and scope equivalent to the claims are intended. [Explanation of Symbols]

[0065] 1: Heating device, 2: Storage compartment, 3: Silica gel particles, 4: Top surface, 5: Bottom surface, 6: Side surface, 7: First sheet, 8: Second sheet, 9: Horizontal surface, 10: Plate

Claims

1. Multiple silica gel particles, A bag-shaped container having a space inside for containing the plurality of silica gel particles, and having a breathable container section, Equipped with, A heating device in which the ratio of the surface area of ​​the containment to the volume of the plurality of silica gel particles sealed in the containment is 130% or more and 160% or less.

2. The work of compression in the direction perpendicular to the base surface applied to the body is 125 gf·cm / cm. ２ The above is the heating device according to claim 1.

3. The heating device according to claim 1, wherein the particle size is 4 mm or less.

4. The aforementioned storage section is formed in a bag shape by joining the first sheet and the second sheet at their outer edges. The heating device according to claim 1, wherein the elasticity of the second sheet is greater than that of the first sheet.

5. The heating device according to claim 1, wherein the shape, when viewed along a direction perpendicular to the base surface, is circular with a diameter of 90 mm or more and 110 mm or less.

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