JPH10127680A - Exothermic bag for footwear and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an exothermic bag for footwear which is of a thin type free from biasing of an exothermic compsn. and has an exothermic property by housing a sheet-like heating element obtd. by holding a mixture composed of hot melt type adhesive powder and exothermic compsn. powder in the gaps of non-woven fabrics made of plant fibers and compressing these fabrics under heating with a mold compressing machine, into a bag having air permeability. SOLUTION: The non-woven fabrics 4 to 6 made of the plant fibers having the many gaps are superposed on each other. The exothermic compsn. powder 7 and the hot melt type adhesive powder 8 are held in one layer of the non-woven fabric 4. This non-woven fabric 4 and the other non-woven fabrics 5, 6 are adhered by the compression under heating with the mold compressing machine and the sheet-like heating element 3 impregnated with water or aq. inorg. electrolyte soln. is housed into the bag 2 having the air permeability. This bag is mounted in the footwear, by which the exothermic bag 1 for footwear for insulating the heat of the feet is obtd. At this time, the exothermic compsn. powder 7 is composed essentially of iron powder and active carbon or iron powder, active carbon and inorg. electrolyte. The hot melt type adhesive powder 8 has a softening temp. of 40 to 200 deg.C and the amt. of the powder to be added is specified to 0.1 to 20 pts.wt. per 100 pts.wt. iron powder.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat generating bag for footwear using a sheet-shaped heat generating element, and more particularly, to a heat generating composition for footwear which is thin, has no unevenness of a heat generating composition, and has excellent heat generating performance. About bags.

[0002]

2. Description of the Related Art Conventionally, exothermic bags containing an oxidizable metal such as iron powder as a main component and generating heat upon contact with oxygen in the air in an air-permeable bag have been widely used as a pottery. It's being used. Further, a heat-producing bag for footwear used for shoes or slippers, etc., in which the shape of the breathable bag is horseshoe-shaped or trapezoidal, has also been proposed (Japanese Utility Model Application Laid-Open No. 59-71618). Each of these footwear heating bags is made of iron powder, activated carbon,
A wet powder obtained by mixing a water retention agent, an aqueous solution of an inorganic electrolyte, and the like is stored in a gas-permeable bag, and is sealed and stored in a non-gas-permeable outer bag until further use. At the time of use, the outer bag is broken to take out the heat generating bag, which is used by being mounted in footwear.

[0003]

However, when the conventional heat generating bag for footwear is used in shoes, the temperature of the heat generating bag for footwear rises rapidly when walking, even if it is warm and comfortable at rest. Not only was there a risk of burns.
On the other hand, if the heat generation temperature of the footwear heating bag is set low so that the temperature becomes comfortable when walking, there is a disadvantage that sufficient heat generation cannot be obtained at rest. In addition, the conventional heat-generating bag for footwear has disadvantages such as swelling when worn in shoes, and deviation of the heat-generating composition during use, resulting in an uncomfortable feeling. Furthermore, if the heat-generating composition is used while being biased, the portion where the heat-generating composition is gathered may locally generate heat at a high temperature, and there is a risk of burns.

On the other hand, the exothermic composition is held in the voids of a multi-layered nonwoven fabric composed of heat-fusible fibers and plant fibers, and the exothermic composition is thermocompressed into a sheet-like heating element and stored in a breathable bag. Heated bags for footwear have also been considered. This heat generating bag for footwear has an excellent characteristic that the heat generating temperature is substantially constant both at rest and during walking. However, since the non-woven fabric made of the heat-fusible fiber has low water retention, the thickness of the sheet-like material is inevitably increased in order to retain moisture, and the heat-fusible fiber is used to form the sheet. When the nonwoven fabric is heated and compressed, it has a strong net-like structure and has a disadvantage of becoming hard.

Further, a plurality of nonwoven fabrics made of vegetable fibers are superimposed on each other by the adhesive force of water, the exothermic composition is held in the voids, and then heated and compressed to form a sheet-shaped exothermic body with a breathable bag. Heating bags for footwear stored in the store are also being considered. This heat generating bag has excellent characteristics that the heat generating bag is thin and stable heat generating performance can be obtained without being affected by the use condition. However, since this heating bag for footwear uses a sheet-like heating element that is superimposed by the adhesive force of water, handling of the sheet-like heating element in its manufacturing process,
When transported and stored in a breathable bag, there is a disadvantage that the layers of the sheet-like material are peeled off. For these reasons, it has been desired to develop a heating bag for footwear that can provide a comfortable temperature without being affected by the use condition, is thin, does not cause discomfort, and is easy to manufacture.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve these problems, and as a result, have found that a mixture of a hot-melt adhesive powder and a heat-generating composition powder is placed in a void of a vegetable fiber nonwoven fabric. It has been found that these problems can be solved by holding the sheet-like heating element obtained by heating and compressing with a mold compressor in a bag having air permeability, and reached the present invention. That is, in the present invention, a plurality of nonwoven fabrics made of vegetable fiber having a large number of voids are laminated, and the exothermic composition powder and the hot-melt adhesive powder are held in at least one of the nonwoven fabrics. At least a part of one layer of the nonwoven fabric and another nonwoven fabric in contact with the one layer of the nonwoven fabric are adhered, and the sheet-like heating element impregnated with water or an inorganic electrolyte aqueous solution is housed in a bag having air permeability. This is a heating bag for footwear.

Further, according to the present invention, a nonwoven fabric made of vegetable fiber is superposed on a lower surface of a nonwoven fabric made of vegetable fiber having a large number of voids, and a heat-generating composition powder and a hot-melt adhesive powder are sprayed from the upper surface of the nonwoven fabric. Then, a nonwoven fabric c made of vegetable fiber is superimposed on the upper surface of the nonwoven fabric a, heated and compressed by a mold compressor, and then a sheet-like heating element impregnated with water or an aqueous electrolyte solution is passed through a breathable bag. A method for producing a heat generating bag for footwear, characterized by being housed in a heat generating bag for footwear.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is mainly applied to a heat generating bag for footwear which is mounted in footwear such as shoes and slippers and used for keeping a foot warm. The heating bag for footwear of the present invention is a heat-generating composition and a hot-melt adhesive powder that generate heat upon contact with oxygen in the air, in the voids of a laminate of plant fiber nonwoven fabric having a large number of voids,
And a sheet-like heating element which is held between the lamination layers and in which the laminate of the nonwoven fabric is superimposed by the heat-pressing adhesive with the adhesive force of a hot-melt adhesive is stored in a breathable bag.

Further, in the method for producing a heat generating bag for footwear of the present invention, the nonwoven fabric made of vegetable fiber b is superimposed on the lower surface of the nonwoven fabric made of vegetable fiber a having a large number of voids. The hot-melt adhesive powder is sprayed to be held in the voids of the nonwoven fabric, and then the nonwoven fabric c made of vegetable fibers is superimposed on the upper surface of the nonwoven fabric a. Alternatively, this is a method for producing a heating bag for footwear in which a sheet-like heating element is obtained by impregnating with an electrolyte aqueous solution, and the sheet-like heating element is stored in a breathable bag.

The heat-producing bag for footwear of the present invention comprises a heat-generating composition and a hot-melt adhesive powder held in a nonwoven laminate. Here, as a method of holding the exothermic composition on the nonwoven fabric, for example, a mixture of iron powder, activated carbon, an inorganic electrolyte, water, and the like is dispersed on the nonwoven fabric, and is held by a method such as applying vibration or pressing. A mixture of powdered raw materials such as iron powder, activated carbon, and inorganic electrolyte may be sprayed on the nonwoven fabric, and the mixture may be vibrated so as to be held in the voids, and then water may be sprayed on the mixture. After the mixture of the powder raw materials except the inorganic electrolyte such as the powder and the activated carbon is spread on the nonwoven fabric and vibrated to be held in the voids, the aqueous solution of the inorganic electrolyte may be sprayed and impregnated. Among these, it is preferable because the state containing no water is easier to hold in the voids of the nonwoven fabric, and further, it is difficult for the method to uniformly penetrate the inorganic electrolyte throughout, and the oxidizable metal It is more preferable that the oxidation of the powder starts at the time of mixing the water. From the above, the exothermic composition is held by the usual method.

Hereinafter, the present invention will be described mainly by a manufacturing method based on a method. In the present invention, the nonwoven fabric a is capable of holding a mixture (hereinafter referred to as a heat-generating composition powder) of a heat-generating composition raw material that generates heat upon contact with air in a void thereof and having a water retention ability. Is big,
For example, it is mainly composed of plant fibers such as pulp, cotton, hemp, rayon, and acetate (regenerated fibers such as rayon and acetate are also included in the plant fibers in the present invention). The production method may be one formed by entanglement of fibers, or one formed by using a synthetic resin, an adhesive, or the like as a binder to the extent that the nonwoven fabric does not have heat-fusing properties. Good. Although the thickness varies depending on the amount of the exothermic composition powder held, etc., it is usually 0.5 to 10 mm,
Preferably it is 1 to 7 mm. The basis weight is usually 20 to 1
50 g / m ^2, preferably from 30 to 100 g / m ^2.

The nonwoven fabric b is for preventing the exothermic composition powder from leaking from the lower surface of the nonwoven fabric a, and is used by being superposed on the lower surface of the nonwoven fabric a. As a material of the nonwoven fabric b, a nonwoven fabric mainly containing plant fibers such as pulp, cotton, hemp, rayon, and acetate, and a paper-like material such as tissue paper are preferable. Usually, a material having a denser structure than that of the nonwoven fabric a is used.
0 g / m ^2, preferably 15 to 40 g / m ^2.

The nonwoven fabric c is for holding the exothermic composition powder remaining on the upper surface of the nonwoven fabric a that cannot be completely retained by the nonwoven fabric a and for preventing the exothermic composition powder from leaking from the upper surface. Used on the upper surface of the nonwoven fabric a. As the material, those having a large number of voids and having a large water retention capacity are preferable, for example, pulp,
It is a nonwoven fabric made of vegetable fibers such as cotton, hemp, rayon, and acetate. The thickness of the nonwoven fabric c varies depending on the holding amount of the heat-generating composition, but is usually 0.2 to 7 mm, preferably 0.5 to 5 mm. In addition, the grammage is usually 10
100 g / m ^2, preferably 20 to 80 g / m ^2.

The raw materials constituting the exothermic composition powder include:
Oxidizable metal powder, activated carbon and the like. The inorganic electrolyte is a component of the exothermic composition powder when mixed with the above raw materials as a solid, and is not included in the exothermic composition powder when impregnated as an aqueous solution after sheet formation. The oxidizable metal powder includes iron powder, aluminum powder, and the like. Usually, iron powder is used, such as reduced iron powder, atomized iron powder, and electrolytic iron powder. Activated carbon is used not only as a reaction aid but also as a water retention agent, and is usually coconut shell charcoal, wood powder charcoal, peat charcoal and the like. As the inorganic electrolyte, alkali metals, alkaline earth metals, chlorides of heavy metals, sulfates of alkali metals and the like are preferable, for example, sodium chloride, potassium chloride, calcium chloride, magnesium chloride, ferric chloride,
Sodium sulfate or the like is used. The exothermic composition refers to a mixture of the exothermic composition powder and water or an aqueous electrolyte solution.

The particle size of the exothermic composition powder is usually 60 mesh or less, preferably 100 mesh or less.
% Or more. The mixing ratio of the heat-generating composition as a whole depends on the properties of the nonwoven fabric, the desired heat-generating performance, and the like, and cannot be specified unconditionally.
Activated carbon is 5 to 20 parts by weight, inorganic electrolyte is 1.5 to 10 parts by weight, and water is 25 to 60 parts by weight with respect to 00 parts by weight. In addition, if desired, a polymer water retention agent, a hydrogen generation inhibitor, an anti-caking agent, and the like can be added.

The hot-melt type adhesive in the present invention is an adhesive which is fused by heat and pressure, and has a property of mixing with a heat-generating composition powder, a softening point, a particle size, a bonding method, and a bonding property with a nonwoven fabric. The softening point is selected in consideration of 40-200 ° C
Preferably, for example, ethylene-vinyl acetate copolymer, copolymers such as ionomers, polyethylene, polypropylene, homopolymers of thermoplastic resins such as polystyrene, or a polymer blend thereof, or these thermoplastic resins as a base polymer, Hot melt adhesives mixed with tackifiers, waxes and the like. These adhesive powders may be used alone or as a mixture.

The particle size of the hot-melt adhesive powder is generally 0.02 to 2 mm in diameter, preferably 0.05 to 1.5 mm.
mm, more preferably 0.1 to 0.8 mm in diameter. The amount of the hot-melt adhesive powder varies depending on the method of addition and cannot be specified unconditionally, but is usually 0.1 to 20 parts by weight, preferably 0.3 to 12 parts by weight, per 100 parts by weight of iron powder.
Parts by weight, more preferably 0.5 to 7 parts by weight.

Next, an example of a structure and a manufacturing method of the heat generating bag for footwear according to the present invention will be described with reference to the drawings, but the present invention is not limited to this example. FIG. 1 is a plan view of the footwear heating bag 1. FIG. 2 shows A of the heating bag 1 for footwear.
FIG. 4 is a cross-sectional view taken along a line A. 2 is a bag having air permeability, and 3 is a sheet-like heating element. Reference numeral 4 denotes a nonwoven fabric a, 5 denotes a nonwoven fabric b, and 6 denotes a nonwoven fabric c. Reference numeral 7 denotes a heat-generating composition, 8 denotes a hot-melt adhesive powder, 9 denotes an adhesive, and 10 denotes a release paper. FIG. 3 shows an example of the manufacturing process of the present invention. 11 is a roll of nonwoven fabric a, 1
2 is a roll of the nonwoven fabric b, 13 is a water spray portion, 14 is a roll portion, 15 is a spray portion of the heat-generating composition powder and the hot-melt adhesive powder, 16 is a roll of the nonwoven fabric c, 17 is a roll portion, 18
Denotes a heating / compression unit, 19 denotes a cutting unit, 20 denotes a water or electrolyte aqueous solution spraying unit, and 21 denotes a filling unit into a bag having air permeability.

Water is sprayed on the lower surface of the nonwoven fabric a4 by the water spraying unit 13, and the nonwoven fabric b is formed on the upper surface of the nonwoven fabric a4 by the roll unit 14.
5 is superimposed on the adhesive force of water. Next, the exothermic composition powder and the hot-melt adhesive powder are sprinkled in the exothermic composition powder dispersing section 15 while being vibrated and held in the voids of the nonwoven fabric a. Next, the nonwoven fabric c6 is superimposed on the upper surface by the roll part 17, further heated and compressed by the heating and compression part 18, and cut into a desired size by the cutting part 19. Next, the water or electrolyte aqueous solution is sprayed in the water or electrolyte aqueous solution spraying section 20. Thus, the sheet-shaped heating element 3 is manufactured. Furthermore, it is stored in a breathable bag at the filling portion 21 into the breathable bag, and the heat-generating bag 1 for footwear is obtained.

In the present invention, the method of spraying the hot-melt adhesive powder is as follows.
In addition to the method of spraying hot-melt adhesive powder on it,
Non-woven fabric a by mixing hot-melt adhesive powder with exothermic composition powder
A method of spraying the heat-melting adhesive powder and then the heat-generating composition powder, and a method of spraying the heat-melting adhesive powder before and after the heat-melting composition powder is sprayed. Can be used. However, the method of spraying the hot-melt adhesive powder before spraying the heat-generating composition powder may clog the nonwoven fabric a or pass through the nonwoven fabric a depending on the particle size of the hot-melt adhesive powder. For this reason, a method in which the exothermic composition powder and the hot-melt adhesive powder are mixed and sprayed, or a method in which the hot-melt adhesive powder is sprayed after the exothermic composition powder is sprayed is preferable. When the hot-melt adhesive powder is sprayed separately from the heat-generating composition powder, the hot-melt adhesive powder may be sprayed uniformly over the entire surface, or may be partially sprayed such as a halftone dot or a grid.

The amount of the exothermic composition retained on the nonwoven fabric is determined according to the thickness of the nonwoven fabric, the desired thickness of the heating element, the desired heat generation performance, and the like.
300 to 5000 g per ² , preferably 700 to 20
00 g. When the holding amount is less than 300 g, the heat generation temperature and the heat generation duration decrease, while the holding amount is 5000 g.
If it is larger, the thickness of the heating element increases, and it is difficult to form a thin and flexible sheet.

The heating and compression can be performed by passing through a heating press or a heating roll. The heat compression can be performed by a flat or flat roll, but in order to improve the shape fixing effect while maintaining the flexibility of the sheet-like material, it is preferable that at least one of the compression surfaces is an embossed surface. The shape of the embossed eye is not particularly limited, but is usually a wavy shape, a tortoise-like shape, a ring shape, a polka dot shape, a network shape, and the like, and a shape in which the heat-generating composition powder can be easily removed by the non-compressed portion during heating and compression is preferable . The ratio of the area of the projections on the embossed surface is not particularly limited, but is usually 0.5 to 60.0%, preferably 5.0 to 40.0%.

The temperature and pressure conditions for the heating and compression are as follows:
Although it depends on the material of the nonwoven fabric a, the nonwoven fabric b, and the nonwoven fabric c, the softening temperature of the hot-melt adhesive and the holding amount of the heat-generating composition powder, for example, when using a heating roll, the temperature is usually 70
And a linear pressure of about 0.1 to 250 kg / cm. As a result, the hot-melt adhesive powder on the surface in contact with the projections is melted and fixed in shape while the laminate is compressed, and a thin sheet-like material is obtained. The thickness of the sheet-shaped heating element is preferably as thin as possible so long as the amount of the heat-generating composition necessary for exhibiting the desired heat-generating temperature, duration and other heat-generating properties can be maintained, and is usually 2.5 mm or less. .

The size and shape of the sheet-like heating element are not particularly limited as long as the size and shape can be accommodated in a breathable bag. For example, the toe shape of a shoe sole, a rectangle, a square, a circle, a semicircle, Oval, semi-elliptical and the like. The amount impregnated with water or the inorganic electrolyte aqueous solution is the total amount of the water or the inorganic electrolyte aqueous solution set as the composition ratio of the exothermic composition, and these are supplied by spraying, dripping, or roll impregnation, and impregnated, and the sheet is impregnated. It becomes a heating element.

In the present invention, the bag having air permeability is a bag in which at least one of the front and back surfaces of the bag is made of a packaging material having air permeability. The air-permeable packaging material does not necessarily need to have its ventilation holes provided uniformly over the entire surface, but may be provided partially. There is no particular limitation on the material of the breathable packaging material, as long as it can supply air in an amount necessary for heat generation of the heat-generating composition and has strength enough to withstand friction or rubbing pressure during use. Often, a nonwoven fabric is attached to a synthetic resin film such as polyethylene, polypropylene, polyester, polyvinyl chloride, etc. to form a fine hole to allow air permeability, or a porous film alone, or a nonwoven fabric, etc. And the like.

The shape of the breathable bag is not particularly limited as long as it can be accommodated in footwear.
For example, any shape such as rectangle, square, circle, ellipse, semicircle, semiellipse, and sole shape can be used, but the toe shape of the sole, semicircle, semiellipse, etc. Particularly suitable for the shape.

In the present invention, an adhesive layer may be provided on the whole or a part of one side of the heat generating bag in order to enhance the fixation of the heat generating bag for footwear at the mounting portion. The pressure-sensitive adhesive may be non-transferable pressure-sensitive adhesive that does not move when the heating bag is stuck in footwear and does not transfer to the footwear side when peeled off. An organic solvent-based or water-based non-transferable pressure-sensitive adhesive such as a rubber-based resin, an acrylic resin-based resin, or a vinyl acetate resin-based resin is preferably used.

When a pressure-sensitive adhesive layer is provided, a release paper is superimposed on the pressure-sensitive adhesive layer so as not to adhere to other objects until it is used. As the release paper, those having properties similar to those used for generally commercially available pressure-sensitive adhesive sheets, tapes, stickers, etc. can be used. It has improved releasability.

The heat generating bag for footwear according to the present invention is sealed and stored in a non-breathable outer bag until the time of use, in order to prevent oxidation of the oxidizable metal. FIG. 2 and FIG. 3 show examples of a heating bag for footwear using a sheet-like heating element in which three layers of nonwoven fabric are laminated and a method of manufacturing the same. However, the present invention may have a two-layer structure of nonwoven fabric a and nonwoven fabric b. A laminate having a two-layer structure, a laminate having a three-layer structure, a laminate having a combination of the two-layer structure and the three-layer structure, or a multilayer structure may be used.

As described above, the exothermic composition and the hot-melt adhesive powder are held in the nonwoven fabric made of vegetable fibers having a large number of voids, and the exothermic body formed into a sheet by heating and compression is stored in a breathable bag. By doing so, it is possible to obtain a comfortable temperature that is not affected by usage conditions such as at rest, walking, and the like. Can now be obtained. Next, the present invention will be described more specifically with reference to examples, but the present invention is not limited thereto.

[0031]

【Example】

Example 1 ^On a tissue paper having a basis weight of 25 g / m ² , water was sprayed on the lower surface to moisten it to a thickness of about 1.1 mm and a basis weight of 40 g / m 2.
² wood pulp non-woven fabric (Kinocross, manufactured by Honshu Paper Co., Ltd.), 90 parts of iron powder, 8 parts of activated carbon,
A mixture of 2 parts of a high molecular water retention agent and 1 part of an ethylene / vinyl acetate copolymer resin powder (H4011-N, manufactured by Sumitomo Seika Co., Ltd.) was sprayed at a rate of 1500 g / m ² , and vibration was applied to the nonwoven fabric to form a nonwoven fabric. It was kept in the void. Next, a nonwoven fabric made of wood pulp (Kinocross, manufactured by Honshu Paper Co., Ltd.) having a thickness of 1.2 mm and a basis weight of 60 g / m ² was overlaid on the upper surface of the nonwoven fabric, and the upper roll surface was embossed in a mesh form. Was passed through a roll heating compressor set at 200 ° C. and a linear pressure of 133 kg / cm to form a sheet. This sheet was cut into a shoe toe having a size of about 60 mm × 80 mm, and a 20% saline solution was sprayed at a rate of 570 g / m ² to obtain a sheet heating element having a thickness of 2 mm.

Next, an acrylic ester-based pressure-sensitive adhesive was applied to the nonwoven fabric side of a sheet in which a nonwoven fabric made of nylon having a basis weight of 50 g / m ² and a polyethylene film having a thickness of 50 μm were bonded. A silicone-treated release paper was overlaid on the adhesive-coated surface to form a non-breathable sheet. A polyethylene microporous membrane (Tyvek 1073B, manufactured by DuPont) having a Gurley type air permeability of 20 seconds / 100 cc specified by ASTM D762 is superimposed on this non-breathable sheet so that the polyethylene sides are in contact with each other. , Size about 8
The shoe sole was cut into a toe shape of 0 mm × 100 mm, and the periphery of the toe-shaped curved portion of the shoe sole was heat-sealed to produce a bag having air permeability. The sheet-like heating element is housed in the bag-like material, and the opening is heat-sealed to have a thickness of about 2.3.
mm heat-producing bags for footwear were produced. During this time, the nonwoven fabric did not peel off and the exothermic composition powder did not fall off.

The heat generating bag for footwear is further sealed in a non-breathable outer bag and stored for 2 days. Then, the heat generating bag for footwear is taken out of the outer bag, and the inside of the athletic shoe is placed so that the microporous membrane side faces upward. The heat generation performance of the heat generation bag for footwear was measured as follows. A copper-constantan thermocouple is attached to the center of the upper surface of the heating bag for footwear, and after sitting in a chair for 20 minutes in an environment of a temperature of 10 ° C. and a humidity of 60%, 5k / h
After walking at a speed of m for 30 minutes, sitting on a chair for another 10 minutes, and measuring the temperature change of the heating bag for footwear at rest and while walking. FIG. 4 shows the results. As a result, 2
After 30 minutes, the temperature reached 30 ° C., and at rest, the temperature was kept constant at around 40 ° C., and the patient was comfortable. In addition, there is no sharp rise in temperature when walking, and it is constant around 40 ° C to 45 ° C.
It was comfortable. In addition, the heat-generating bag for footwear could be easily mounted without mounting the heat-generating composition at the time of mounting. In addition, even when walking, the exothermic composition did not shift, and no discomfort occurred.

Comparative Example 1 Iron powder 5 g, activated carbon 0.5 g, salt 0.5 g, water 1.5
g, a polymer exothermic agent 0.2 g was mixed in a nitrogen atmosphere, and the exothermic composition obtained was filled in a bag having the same air permeability as in Example 1, and an approximately 2 mm thick exothermic bag for footwear was prepared. Produced.
After sealing the heating bag in a non-breathable outer bag and storing it for 2 days, the heating bag for footwear was taken out of the outer bag, and the inside of the same athletic shoe as in Example 1 was placed so that the microporous membrane side was on the upper side. The heat generating performance of the heat generating bag for footwear was measured in the same manner as in Example 1 by attaching the heat generating bag to the bottom of the toe side. FIG. 4 shows the results.

As a result, the temperature reached 30 ° C. two minutes after the wearing and was comfortable in a stationary state, but reached a maximum of 62 ° C. when walking, and felt very hot and tingling. In addition, even at rest after walking, the temperature dropped to only 50 ° C., which was quite hot. Pain remained in the soles even after the heating bag was removed. In addition, this heat generating bag for footwear had a bias in the heat generating composition when worn and while walking, giving a sense of incongruity. After use, the exothermic composition had solidified.

Comparative Example 2 A basis weight of 75% made of 65% cotton and 35% heat-fusible fibers
g / m ² , a thickness of 3.0 mm, a basis weight of 23
g / m ² of tissue paper, and a mixture of 90 parts of iron powder, 8 parts of activated carbon, and 2 parts of a high molecular weight water-retaining agent was sprayed thereon at a rate of 1500 g / m ² , and vibration was applied to form a nonwoven fabric. It was kept in the void. Next, heat-fusible polyester 50%, polyester 50%
Of non-woven fabric having a basis weight of 40 g / m ² and a thickness of 1.9 mm, and a tissue paper having a basis weight of 23 g / m ² was further laminated thereon. After this, it was heated and compressed under the same conditions as in Example 1 to form a sheet.
It was cut into a shoe toe shape of mx 80 mm and sprayed with a saline solution to obtain a sheet-like heating element. This heating element was housed in the same air-permeable bag as in Example 1 to obtain a 3 mm-thick heating bag for footwear.

After the heat-generating bag for footwear was further sealed in an air-impermeable outer bag and stored for 2 days, the heat-generating bag for footwear was removed from the outer bag, and the heat generation of the heat-generating bag for footwear was performed in the same manner as in Example 1. The properties were measured. As a result, a comfortable temperature was obtained both when standing still and when walking, but the entire heat generating bag for footwear was not only hard but also thick and uncomfortable.

[0038]

According to the present invention, a stable temperature can be obtained without being affected by usage conditions such as at rest and during walking, and the content does not shift, and the footwear is thin and does not cause discomfort. A heating bag for use has been obtained. Further, the sheet-shaped material was not peeled off in the manufacturing process, and stable manufacturing was enabled.

[Brief description of the drawings]

FIG. 1 is a plan view of a heating bag for footwear.

FIG. 2 is a cross-sectional view of the heating bag for footwear taken along line AA.

FIG. 3 is an example of a manufacturing process of a heating bag for footwear.

FIG. 4 is a diagram showing heat generation characteristics of the heat generation bag for footwear in Example 1 and Comparative Example 1.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heating bag for footwear 2 Bag having air permeability 3 Sheet heating element 4 Nonwoven fabric a 5 Nonwoven fabric b 6 Nonwoven fabric c 7 Heat generating composition 8 Heat melting type adhesive powder 9 Adhesive 10 Release paper 11 Roll of nonwoven fabric 12 Nonwoven fabric b Roll 13 water spraying part 14 roll part 15 exothermic composition powder and hot melt type adhesive spraying part 16 non-woven fabric c roll 17 roll part 18 heat compression part 19 cutting part 20 water or electrolyte aqueous solution spraying part 21 has air permeability Filling section for bags

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Minako Suzuki, Inventor 5181 Tamura, Hiratsuka-shi, Kanagawa Prefecture Japan Pionix Co., Ltd.

Claims (7)

[Claims] A nonwoven fabric made of vegetable fibers having a large number of voids is laminated in a plurality of layers, and at least one of the nonwoven fabrics holds a heat-generating composition powder and a hot-melt adhesive powder. At least a portion of one nonwoven fabric and another nonwoven fabric in contact with the one nonwoven fabric are adhered, and a sheet-like heating element impregnated with water or an aqueous inorganic electrolyte solution is provided.
A heat-producing bag for footwear, which is housed in a breathable bag. 2. A nonwoven fabric made of vegetable fiber, a nonwoven fabric made of vegetable fiber overlaid on the lower surface of nonwoven fabric, and a nonwoven fabric made of vegetable fiber overlaid on the upper surface of nonwoven fabric. The exothermic composition powder and the hot-melt adhesive powder are held between the layers of the non-woven fabric c and the non-woven fabric c, and at least a part of the non-woven fabric a and the other non-woven fabric in contact with the non-woven fabric a are bonded by heat compression of a mold compressor, and water or A heating bag for footwear, wherein a sheet-like heating element impregnated with an aqueous inorganic electrolyte solution is housed in a breathable bag. 3. A non-woven fabric made of a vegetable fiber having a large number of voids.
A nonwoven fabric b made of vegetable fiber is superimposed on the lower surface of the nonwoven fabric, and the exothermic composition powder and the hot-melt adhesive powder are sprayed from the upper surface of the nonwoven fabric a to be held in the voids. And heating and compressing with a mold compressor, and then storing a sheet-like heating element impregnated with water or an aqueous electrolyte solution in a gas-permeable bag. 4. The exothermic bag for footwear according to claim 1, wherein the exothermic composition powder comprises iron powder, activated carbon, or iron powder, activated carbon, or an inorganic electrolyte as a main component. 5. The method for producing a heat generating bag for footwear according to claim 3, wherein the exothermic composition powder comprises iron powder, activated carbon, or iron powder, activated carbon, or an inorganic electrolyte as a main component. 6. The hot-melt adhesive powder has a softening point of 40 to 20.
The heating bag for footwear according to claim 1 or 2, wherein the heating bag is at 0 ° C and the amount of addition is 0.1 to 20 parts by weight per 100 parts by weight of iron powder. 7. The hot-melt adhesive powder has a softening point of 40 to 20.
The method for producing a heat generating bag for footwear according to claim 3, wherein the heating bag is at 0 ° C and the amount of the additive is 0.1 to 20 parts by weight per 100 parts by weight of iron powder.