JP2005160659A - Heat generator structure for direct application to skin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat generating structure to be directly applied on the skin which causes little pain when removed despite of a necessary adhesive strength. <P>SOLUTION: The heat generating structure to be directly applied on the skin is equipped with a breathable sheet layer, an exothermic agent composite layer, an airtight sheet layer, a nonwoven fabric layer and an adhesive layer in this sequence, wherein the exothermic agent composite layer is enclosed in a bag which is formed of the breathable sheet layer and the airtight sheet layer, the adhesive layer is formed partially on the nonwoven fabric layer, and the adhesive strength of the adhesive layer is 2.80-3.50 newton when it is measured by a method following the test method of the Japanese Pharmacopoeia D-935 (the adhesive strength test of an adhesive plaster). <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a heat generating body structure that is used by being directly attached to the skin.

  As a tool for easily warming a part of a human body, a disposable type heat generating body structure, a so-called disposable hood is known. Some of these heat generator structures are used by being directly applied to underwear or skin, especially for the latter, in order to prevent the heat generator structures from peeling off during use, and In order to prevent skin damage such as redness and rash from occurring even when used for a long time, various proposals such as the following have been made.

  In the sweat-absorbing thermal structure described in Patent Document 1, one surface of the bag formed by enclosing the exothermic composition has a three-layer structure of a synthetic resin film layer, a water-absorbing layer, and a porous synthetic resin film layer. In addition, a pressure-sensitive adhesive layer is partially formed in a lattice or stripe shape outside the porous synthetic resin film layer. Because of this structure, body fluids such as sweat and waste products generated on the skin surface due to heat are absorbed by the water absorption layer through the pores of the porous synthetic resin film layer in areas where there is no pressure-sensitive adhesive layer. Therefore, the skin surface is kept hygienic and the adhesion between the thermal structure and the skin is enhanced.

  In the exothermic sheet described in Patent Document 2, the pressure-sensitive adhesive layer for sticking this sheet to the skin is a spot having an outer diameter of 3 to 5 mm, and the total area of the spot is defined as the back surface of the sheet (the pressure-sensitive adhesive). It is limited to 30 to 70% of the area of the surface on which the layer is provided. Since the portion of the heat generating sheet without the adhesive layer is a continuous non-adhesive portion, skin respiration and sweating are not inhibited and the heat generating sheet is not peeled off by perspiration.

  In the exothermic sheet described in Patent Document 3, the outer side of one surface of the bag body encapsulating the exothermic composition is composed of a hydrophilic non-woven fabric, and a part of the outer side of the non-woven fabric layer is partially The hydrophobic pressure-sensitive adhesive layer is formed in stripes or dots so as to enter the nonwoven fabric layer. Since this heat generating sheet has a part with a large amount of heat supply (part with an adhesive) and a part with a small amount (part without an adhesive), heat storage is suppressed, thereby preventing heat generation and pain. In addition, since the hydrophilic nonwoven fabric absorbs sweat and releases it to the outside as a vapor, this also provides an effect of preventing heat accumulation, prevents moisture from being stuffed, and prevents the sheet from being easily peeled off by the sweat of the heating sheet. Is done.

  In the thermal patch described in Patent Document 4, one surface of a bag formed by enclosing an exothermic composition is composed of a hydrophilic layer mainly composed of hydrophilic fibers and a hydrophobic layer mainly composed of hydrophobic fibers. The adhesive layer is intermittently formed on the outside of the laminate. Because of this structure, secretions such as sweat are absorbed by the thermal patch.

Japanese Patent No. 2826667 JP-A-9-557 JP 2000-139990 A JP 2001-120588 A

  An object of the present invention is to provide a heat generator structure for direct application to the skin that has the required adhesive strength but has less pain when peeled off.

  In addition, the present invention is a heat generator for direct application to the skin that is excellent in absorbability of liquids such as sweat generated from the human body, and heat generated by the heat generating composition is appropriately conducted to the human body. The object is to provide a structure.

  The inventors have made intensive efforts to achieve the above object, and as a result, have made the present invention.

  That is, the present invention comprises a breathable sheet layer, a heat generating composition layer, a non-breathable sheet layer, a nonwoven fabric layer, and an adhesive layer in this order, and the heat generating composition layer comprises a breathable sheet layer and a non-breathable sheet. A heat generating body structure enclosed in a bag formed of a layer, wherein the adhesive layer is partially formed on the nonwoven fabric layer, and the adhesive strength of the adhesive layer is Japan A heat generator structure for direct application to the skin, characterized in that it is 2.80 to 3.50 Newton as measured by the following method according to the test method of Pharmacopoeia D-935 (Adhesive strength test of adhesive bandage) Offer things.

(Measurement method of adhesive strength of adhesive layer)
(1) One surface of an acrylic resin plate (9.5 cm or more × 13 cm or more) is wiped with ethanol.

  (2) The length of the acrylic resin plate is 9.5 cm or longer on one side of the thermal generator structure (9.5 cm × 13 cm), and one side of 9.5 cm is put on the acrylic resin plate. .

  (3) With the thermal generator structure facing down, an 800 g weight is placed on the acrylic resin plate to which the thermal generator structure is affixed, and left in this state at 37 ° C. for 30 minutes.

  (4) Fold the thermogen generator structure to a 180-degree angle at a half of its length (13 cm).

  (5) Hook the free end generated by folding the thermal generator structure on the tension jig of the tensile tester, and fix the end of the acrylic resin plate to which the thermal generator structure is not attached.

  (6) The thermal generator structure is pulled upward at a tensile speed of 50 mm / min, and the thermal generator structure is peeled off from the acrylic resin plate.

  (7) The maximum force in the step (6) is defined as the adhesive force of the adhesive layer of the thermal generator structure.

  The heat generator structure for direct application to the skin of the present invention includes an embodiment having one or two or more of the following elements (A) to (E).

(A) The adhesive strength of the adhesive layer is measured by JIS Z 0237 (adhesive tape / adhesive sheet test method), and is ball number 21-30,
(B) The thickness of the adhesive layer is 20 to 100 μm.
(C) The total area of the adhesive layer is 20 to 70% of the total area of the affixed surface.
(D) The ends of the adhesive layer are expressed at substantially uniform intervals on each of the four sides of the pasting surface,
(E) A nonwoven fabric consists of a mixture of a hydrophilic fiber and a hydrophobic fiber, and (F) Furthermore, it has a nonwoven fabric layer on the outer side of a breathable sheet layer.

  Although the heat generating body structure for direct application to the skin of the present invention has the required adhesive strength, it shows the effect of less pain when peeled off. In addition, the pain at the time of peeling arises, for example, because the hair adhering to the adhesive layer of the heat generating body structure is pulled or the keratin of the skin is peeled off.

  The heat generating body structure for direct application to the skin of the present invention in which the end portions of the adhesive layer are expressed at substantially uniform intervals on each of the four sides of the application surface is particularly difficult to peel off during use.

  The heat generating body structure for direct application to the skin of the present invention, in which the nonwoven fabric is a mixture of hydrophilic fibers and hydrophobic fibers, is further excellent in absorbability of liquids such as sweat generated from the human body, and exothermic agent It also shows the effect that the heat generated by the composition is properly conducted to the human body.

  The heat generator structure for direct application to the skin of the present invention having a non-woven fabric layer on the outer side of the breathable sheet layer further exhibits an effect of being excellent in touch and shape retention.

  In the following, the present invention will be described in detail with reference to preferred embodiments thereof.

  First, the physical structure of the heat generating body structure for direct application to the skin of the present invention will be described with reference to the drawings.

  FIG. 1: is a cross-sectional schematic diagram which shows the suitable Example of the heat generating body structure for direct sticking to the skin of this invention. The heat generating body structure 10 for direct application to the skin of the present invention comprises a breathable sheet layer 1, a heat generating agent composition layer 3, a non-breathable sheet layer 5, a nonwoven fabric layer 7 and an adhesive layer 9 in this order from the outside. The exothermic composition layer 3 is enclosed in a bag 6 formed of a breathable sheet layer 1 and a non-breathable sheet layer 5.

  FIG. 2 is a schematic cross-sectional view showing another preferred embodiment of the heat generating body structure for direct application to the skin of the present invention. The heat generating body structure 20 for direct application to the skin of the present invention has a nonwoven fabric layer 12, a breathable sheet layer 1, a heat generating agent composition layer 3, a non-breathable sheet layer 5, a nonwoven fabric layer 7 and an adhesive in order from the outside. The layers 9 are provided in this order, and the exothermic composition layer 3 is enclosed in a bag 6 formed by the breathable sheet layer 1 and the non-breathable sheet layer 5.

  In the embodiment shown in FIGS. 1 and 2, the non-breathable sheet layer 5 and the nonwoven fabric layer 7 are bonded together by heat sealing. The non-breathable sheet layer 5 and the nonwoven fabric layer 7 may be bonded with an adhesive. In that case, an adhesive layer exists between the non-breathable sheet layer 5 and the nonwoven fabric layer 7. Further, the adhesion between the air-impermeable sheet layer 5 and the nonwoven fabric layer 7 may be complete or partial.

  In these examples, the air-permeable sheet layer 1 and the non-air-permeable sheet layer 5 are bonded together by heat sealing to form the bag body 6. Adhesion around the breathable sheet layer 1 and the non-breathable sheet layer 5 may also be due to an adhesive.

  In the embodiment shown in FIG. 2, the non-woven fabric layer 12 and the breathable sheet layer 1 are partially sealed by heat sealing or adhesive so that air can reach the exothermic composition layer 3 through these layers. Is bound to.

  One of the features of the heat generator structure for direct application to the skin of the present invention is that the adhesive layer is partially formed on the nonwoven fabric layer. Here, “partially formed” means that there is a portion having no adhesive layer on the nonwoven fabric layer. The portion without the adhesive layer may be a continuous phase or a discontinuous phase.

  The adhesive layer is, for example, a lattice shape as shown in FIG. 3, a crossed bias shape as shown in FIG. 4, a shape of an aggregate of a number of points as shown in FIG. 5, and a striped pattern shape as shown in FIG. Formed with.

  Another feature of the heat generating body structure for direct application to the skin of the present invention is that the adhesive strength of the adhesive layer is measured by the following method according to the test method of Japanese Pharmacopoeia D-935 (adhesive strength test of adhesive bandage). And 2.80 to 3.50 Newton. The adhesive strength of the adhesive layer is preferably 2.90 to 3.50 Newton, and more preferably 3.00 to 3.50 Newton.

(Measurement method of adhesive strength of adhesive layer)
(1) One surface of an acrylic resin plate (9.5 cm or more × 13 cm or more) is wiped with ethanol.

  (2) The length of the acrylic resin plate is 9.5 cm or longer on one side of the thermal generator structure (9.5 cm × 13 cm), and one side of 9.5 cm is put on the acrylic resin plate. .

  (3) With the thermal generator structure facing down, an 800 g weight is placed on the acrylic resin plate to which the thermal generator structure is affixed, and left in this state at 37 ° C. for 30 minutes.

  (4) Fold the thermogen generator structure to a 180-degree angle at a half of its length (13 cm).

  (5) Hook the free end generated by folding the thermal generator structure on the tension jig of the tensile tester, and fix the end of the acrylic resin plate to which the thermal generator structure is not attached.

  (6) The thermal generator structure is pulled upward at a tensile speed of 50 mm / min, and the thermal generator structure is peeled off from the acrylic resin plate.

  (7) The maximum force in the step (6) is defined as the adhesive force of the adhesive layer of the thermal generator structure.

  This method is based on the premise that the adhesive force is measured using a thermal generator structure having a size of 9.5 cm × 13 cm. Since this adhesive force is proportional to the width of the thermal generator structure, when measurement is performed using a thermal generator structure whose width is not 9.5 cm, the width is 9.5 cm by conversion. Find the adhesive strength in some cases.

  Moreover, the heat generating body structure of the present invention preferably has a ball number of 21 to 30, as measured by JIS Z 0237 (adhesive tape / adhesive sheet test method). It is more preferable that it is -30, and it is especially preferable that it is 23-29.

  In the heat generating body structure of the present invention, it is preferable that the end portions of the adhesive layer are expressed at substantially uniform intervals on each of the four sides of the sticking surface. Here, “substantially uniform spacing” means not only the case where the end portions 9a, 9b, 9c, 9d, etc. of the adhesive layer 9 are arranged at a uniform spacing d as shown in FIG. As shown in the example, the distance between the end portions of the adhesive layer 9 is not one kind (that is, the distance between the end portions 9m and 9n, the distance between the end portions 9o and 9p, etc. (narrow interval d1), The interval between the portions 9n and 9o and the interval between the end portions 9p and 9r (the wide interval d2) is a concept that includes a case where a plurality of types of intervals are regularly expressed.

  The total area of the adhesive layer is not particularly limited, but is, for example, 20 to 70%, preferably 20 to 60% of the total area of the pasting surface (that is, one surface of the heat generating body structure), 25 It is particularly preferred that it is ˜55%.

  Although the thickness of an adhesion layer is not specifically limited, For example, it is 20-100 micrometers, It is preferable that it is 25-80 micrometers, and it is especially preferable that it is 30-50 micrometers.

  Next, the material etc. which comprise each part of the heat generating body structure for direct sticking to the skin of this invention are demonstrated concretely.

  The exothermic composition layer of the heat generator structure for direct application to the skin of the present invention is composed of an aeration exothermic composition. Although the component mix | blended with this ventilation heat generating agent composition will not be specifically limited if it is a component conventionally used for the ventilation heat generating agent composition, For example, it will be as follows.

  Examples of chemical exothermic agents include metal powders such as iron powder (reduced iron powder, atomized iron powder, etc.). Examples of reaction aids include metal halides such as sodium chloride, potassium chloride, magnesium chloride, calcium chloride, ferrous chloride, ferric chloride, potassium sulfate, sodium sulfate, magnesium sulfate, copper sulfate, ferrous sulfate Examples thereof include metal sulfates such as iron and ferric sulfate. Examples of the water retention agent include activated carbon, alumina, silica gel, zeolite, charcoal, and a water-absorbing polymer compound. Of course, water is also used. Examples of other additives include polymer compounds such as carboxymethyl cellulose, starch acrylate, polyethylene, polypropylene, polystyrene, bentonite, vermiculite, perlite, charcoal and the like.

  As the ventilation heat generating agent composition, it is preferable to use one having a prescription in which metal powder such as iron powder is not easily biased.

  The ventilation heat generating agent composition is preferably processed into a sheet shape. In that case, the thickness is preferably 5 mm or less, more preferably 0.5 to 4 mm, and particularly preferably 1 to 2 mm.

  In the heat generating body structure for direct application to the skin of the present invention, the bag body in which the exothermic composition layer is encapsulated is composed of a breathable sheet on one side and the other side on the other side. It is composed of a non-breathable sheet.

  Examples of materials for the breathable sheet and non-breathable sheet constituting the bag body include polyolefins such as polyethylene and polypropylene, polyamides such as nylon, polyesters such as polyethylene terephthalate, ethylene-vinyl acetate copolymer and saponification thereof. Products, ethylene copolymers such as ethylene-alkyl (meth) acrylate copolymer, polyvinyl chloride, polyvinylidene chloride, polyurethane, polystyrene and the like. Natural rubber, recycled rubber, and synthetic rubber can also be used.

  A typical example of the breathable sheet is a non-breathable polymer film provided with vent holes (for example, a moisture-permeable porous film). In the present specification, the term “moisture permeable” may be used, but the fact that moisture can pass means that gas can pass, that is, there is “moisture permeable”. It means that there is also breathability.

  In the thermal heating element structure for direct application to the skin of the present invention, a layer of another material (nonwoven fabric layer in the example of FIG. 2) is provided outside the breathable sheet layer 1 as shown in FIG. 12) may be laminated. However, the layer of the other material provided outside the breathable sheet layer must be breathable. Examples of other materials constituting the layer provided outside the breathable sheet layer used in the present invention include woven fabric, nonwoven fabric, knitted fabric, and paper.

Since the air permeability of the air permeable surface affects the heat generation characteristics, the air permeable sheet layer alone or a composite of the air permeable sheet and a layer of other air permeable material has a moisture permeability [JIS Z 0208 (1976)], and selecting and processing a material constituting the breathable surface so as to have a moisture permeability of 200 to 500 g / m ² · 24 hours (preferably 250 to 400 g / m ² · 24 hours) It is preferable to do.

  It should be noted that a method for processing a material constituting the air permeable surface so that the air permeable surface has a desired air permeability, for example, a method for adjusting the air permeability by adhesion when using a laminate, or a porous material having a desired air permeability. The preparation method of a quality film is well-known.

  When a moisture-permeable porous film is used as the breathable sheet, the thickness is usually 100 μm or less, preferably 20 to 80 μm, more preferably 40 to 60 μm.

When the air permeable layer provided outside the air permeable sheet layer is composed of woven fabric, nonwoven fabric or paper, the thickness of the layer is expressed by basis weight, and is usually 200 g / m ² or less, preferably Is 20 to 120 g / m ² , more preferably 40 to 100 g / m ² . In addition, when using a nonwoven fabric, it is preferable that they are a spunlace or a spun bond nonwoven fabric. Examples of the nonwoven material include rayon, nylon, polyester, acrylic, polypropylene, vinylon, polyethylene, urethane, cotton, and cellulose.

  A typical example of the non-breathable sheet constituting the other surface (non-breathable surface) of the bag is a non-breathable polymer film such as a polyethylene film. The thickness of the non-breathable polymer film is usually 100 μm or less, preferably 10 to 70 μm, more preferably 20 to 50 μm, and particularly preferably 25 to 45 μm.

  Examples of the polymer compound constituting the breathable sheet and non-breathable sheet include polyethylene, polypropylene, polyester, polyamide, polyvinyl chloride, polyvinylidene chloride, polyurethane, polystyrene, ethylene-vinyl acetate copolymer, polycarbonate and the like. Can be mentioned.

  The breathable sheet and the non-breathable sheet are not limited to a single layer film, and may be a multilayer film.

  At least one of a breathable sheet and a non-breathable sheet constituting the bag (in the case of a multilayer film, at least the innermost layer of these sheets) is a polymer film having heat sealability, such as a metallocene. -It is preferable that it is a polyethylene film.

  In the heat generating body structure for direct application to the skin of the present invention, the nonwoven fabric layer located on the outer side (side facing the skin) of the non-breathable sheet layer constituting one surface of the bag is a heating element composition. It plays a role of transmitting heat generated by the human body to the human body, absorbing a liquid such as sweat, and a support for maintaining the shape of the thermal generator structure.

Although it does not specifically limit about the nonwoven fabric which comprises the nonwoven fabric layer located in the outer side of a non-breathable sheet layer, It is preferable that it is a spunlace or a spun bond nonwoven fabric. Further, as the non-woven fabric, basis weight preferably has 20 to 80 g / ^{m 2,} more preferably a 30~70g / ^{m 2,} particularly preferably from 40 to 50 g / ^{m 2.}

  It is preferable to use both hydrophilic fibers and hydrophobic fibers as the nonwoven fabric material. This is because hydrophilic fibers are excellent in absorbing liquid such as sweat, and hydrophobic fibers are excellent in thermal conductivity. When the hydrophilic fiber absorbs a liquid such as sweat, the thermal conductivity of the nonwoven fabric layer is lowered, so that the effect of preventing low temperature burns is enhanced. In consideration of the characteristics of each of such hydrophilic fibers and hydrophobic fibers, it is preferable to use a mixture of hydrophilic fibers: hydrophobic fibers = 10: 90 to 70:30 (weight ratio) as a nonwoven fabric material. 20:80 to 70:30 (weight ratio) is more preferable, and a mixture of 30:70 to 50:50 (weight ratio) is particularly preferable.

  Examples of hydrophilic fibers include natural fibers such as cotton, wool, silk, hemp, and wood pulp, cellulose fibers such as rayon and cupra, polyvinyl alcohol fibers, cellulose acetate fibers, superabsorbent fibers (for example, crosslinked acrylate fibers, Fibers obtained by hydrolyzing the surface of acrylic fibers by post-processing, fibers obtained by graft polymerization of acrylic acid or methacrylic acid on fibers such as polyester), and examples of hydrophobic fibers include polyester. And fibers made of nylon, acrylic and the like.

  Examples of the pressure-sensitive adhesive composition constituting the pressure-sensitive adhesive layer partially formed on the nonwoven fabric layer include a rubber-based pressure-sensitive adhesive composition, an acrylic pressure-sensitive adhesive composition, and other thermoplastic resins (for example, polyamide-based, polyethylene) And pressure-sensitive adhesive compositions mainly composed of a cellulose-based resin).

  Examples of the pressure-sensitive adhesive used in the rubber-based pressure-sensitive adhesive composition include diene polymer compounds, specifically, natural rubber, synthetic rubber, or a mixture thereof. Synthetic rubbers include styrene-isoprene block copolymer rubber, styrene-isoprene-styrene block copolymer rubber, styrene-isobutylene-styrene block copolymer rubber, styrene-butadiene rubber, polyisoprene rubber, butyl rubber, chloroprene. Examples thereof include rubber, nitrile rubber, polysulfide rubber, and silicone rubber.

  As the pressure-sensitive adhesive used in the acrylic pressure-sensitive adhesive composition, conventionally used n-butyl (meth) acrylate, hexyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate , One or more (meth) acrylic esters such as tridecyl (meth) acrylate, and (meth) acrylic acid, maleic acid, maleic anhydride, hydroxyethyl acrylate, hydroxypropyl acrylate, copolymerizable with the ester , Acrylamide, dimethylacrylamide, aminoethyl methacrylate, functional monomers such as methacrylic acid (meth) acrylate, or copolymers with vinyl monomers such as acrylonitrile, vinyl acetate, and vinyl propionate.

  The properties of the pressure-sensitive adhesive composition used to form the pressure-sensitive adhesive layer are particularly limited as long as it can be easily applied to the surface of the nonwoven fabric layer, such as an emulsion, a solvent solution, an aqueous solution, a hot-melt type, etc. Not.

  When the heat generating body structure for direct application to the skin of the present invention is not used, the surface of the adhesive layer is covered with a release sheet. Any material may be used for the release sheet as long as it is conventionally used for a sheet for covering a pressure-sensitive adhesive layer of a heating element, that is, a release sheet. For example, various plastic films, thin metal layers, and laminates of plastic films and paper are used as release sheets. The release sheet may be coated with a release coating agent such as silicone, alkyl acrylate, or fluorine. Examples of the polymer compound constituting the plastic film include polyester, polypropylene, polyethylene, alkylbenzene sulfonic acid, and polyvinyl chloride.

  The heat generator structure for direct application to the skin of the present invention (however, the surface of the adhesive layer is covered with a release sheet) is stored in an outer bag. The outer bag is made of a moisture-resistant and air-impermeable material. Since the outer bag is non-breathable, the exothermic agent in the ventilating exothermic composition constituting the exothermic composition layer does not undergo a chemical reaction and is therefore stored without generating heat. When the outer bag is opened, air (oxygen) passes through the bag of the heating element and reaches the heating agent, thereby starting a chemical reaction and releasing reaction heat.

  A typical example of the outer bag material is a laminate of an aluminum thin layer and a polymer film.

  Next, the manufacturing method of the heat generating body structure for direct application to the skin of the present invention (however, the surface of the adhesive layer is covered with a release sheet and enclosed in an outer bag) will be described.

  When manufacturing the heat generating body structure 10 shown in FIG. 1, first, a breathable sheet (becomes the breathable sheet layer 1) and an adhesive layer 9 (this is a release sheet not shown) on one side. Non-breathable sheet (becomes non-breathable sheet layer 5) is bonded to the surface of the non-woven fabric (becomes non-woven fabric layer 7) that is partially formed by the non-adhesive layer 9 A material A is prepared. In addition, formation of the adhesion layer in one surface of a nonwoven fabric is performed using coating machines, such as an attached gravure system and a screen printing system, for example. The surface is covered with a release sheet almost simultaneously with the formation of the adhesive layer. Adhesion between the nonwoven fabric and the non-breathable sheet is, for example, adhesion by heat sealing or an adhesive, and can be full adhesion or partial adhesion.

  When the thermal generator structure 20 shown in FIG. 2 is manufactured, a breathable sheet and a non-woven fabric (which becomes the non-woven fabric layer 12) are partially used instead of the breathable sheet (which becomes the breathable sheet layer 1). Sheet-like material B bonded to each other is used.

  The breathable sheet (or sheet-like material B) and the sheet-like material A are arranged so that the breathable sheet and the non-breathable sheet face each other.

  The width direction of the air-permeable sheet (or sheet-like material B) and the sheet-like material A is heat-sealed, and then both sides thereof are heat-sealed in the longitudinal direction to form a chamber. This chamber is charged with the ventilation exothermic composition. Again, the width direction of these sheet-like materials is heat-sealed, and then the longitudinal direction is heat-sealed in the same manner as described above to form a chamber, and the ventilation heat generating composition is charged. The chamber into which the ventilation heat generating composition is charged is pressed to make the ventilation heat generation composition layered. Thereafter, the same operation is repeated to obtain a continuous encapsulated body of the ventilation heat generating composition.

  Next, the heat seal part in the width direction of the continuous encapsulant is cut to separate one thermal heating element structure for direct application to the skin (however, the adhesive layer is covered with a release sheet). This is enclosed in an outer bag made of an oxygen-impermeable material. This cutting and sealing in the outer bag is repeated.

  When using the thermal heating element structure for direct application to the skin of the present invention, it is preferable that the thermal heating element structure is taken out from the outer bag and then applied to the skin while peeling the release sheet.

  Hereinafter, the present invention will be described more specifically by way of examples.

(Preparation of ventilation exothermic composition)
With the formulation shown in Table 1, an aeration exothermic agent composition was prepared by a conventional method.

(Manufacture of thermal heating element structure of invention example)
Polyester / rayon (weight ratio 80:20) spunlace nonwoven fabric (Asahi Kasei, basis weight: 40 g / m ² ), styrene / isoprene / styrene block copolymer adhesive (N126, ME126) 4 was applied to form an adhesive layer, and this adhesive layer was covered with a polyester film (silicone-coated, Toyo Metallizing, therapy, thickness: 38 μm).

  Table 2 shows the width of the adhesive layer, the interval between the adhesive layers, and the thickness of the adhesive layer.

  A commercially available non-breathable polyethylene film (Minacel, thickness: 40 μm) was bonded to the nonwoven fabric on which the adhesive layer was formed by heat sealing, to obtain a sheet A.

A polyethylene porous film (manufactured by Kojin, TSF-EU, thickness: 50 μm) is partially bonded to a polyester spunlace nonwoven fabric (manufactured by Asahi Kasei, basis weight: 60 g / m ² ) to obtain a sheet B It was. The moisture permeability [JIS Z 0208 (1976)] measured by the Lissy method of the sheet-like material B was 310 g / m ² · 24 hours.

  The sheet-like material A and the sheet-like material B were heat-sealed in the width direction with the non-breathable polyethylene film and the polyethylene porous film facing each other. Next, 20 g of the ventilation heat generating composition having the formulation shown in Table 1 was charged while forming a chamber by heat sealing in the longitudinal direction.

  Again, the width direction of these sheets was heat-sealed. The chamber into which the ventilation exothermic agent composition was charged was pressed to make the ventilation exothermic composition into a layer having a thickness of about 1.5 mm. Thereafter, the same operation was repeated.

  It cut | disconnected in the heat seal part of the width direction, and separated one thermal heating element structure.

  The size of the thermal heating element structure produced in this way was 9.5 cm × 13 cm, and the width of the surrounding heat seal part was 6 mm.

  As a heating element structure for a comparative example, a heating element structure manufactured by Company M (Comparative Example 1) having an adhesive layer on the entire surface of the nonwoven fabric and a heating element structure manufactured by Company H having an adhesive layer in the shape shown in FIG. (Comparative Example 2) was prepared. These sizes were also 9.5 cm × 13 cm. The width of the adhesive layer, the interval between the adhesive layers, and the thickness of the adhesive layer of these thermal heating element structures are shown in Table 2.

(Test Example 1)
The adhesive strength of the adhesive layer of the thermal heating element structure was measured by the following method according to the test method of Japanese Pharmacopoeia D-935 (Adhesive strength test of adhesive bandage). Five samples were prepared, the adhesive strength of those adhesive layers was measured, and the average value was determined. The results are shown in Table 2.

(Measurement method of adhesive strength of adhesive layer)
This will be described with reference to FIG.

  (1) One surface of the acrylic resin plate 15 (9.5 cm × 13 cm) is wiped with ethanol.

  (2) The length of the acrylic resin plate 15 is set to one side of 9.5 cm so that one side of the heat generating body structure 70 is 9.5 cm, and the heat generating body structure 70 is attached to the acrylic resin plate 15.

  (3) With the thermal generator structure 70 facing down, an 800 g weight 17 is placed on the acrylic resin plate 15 to which the thermal generator structure 70 has been attached, and left in this state at 37 ° C. for 30 minutes (FIG. 7 (1)).

  (4) The thermal generator structure 70 is folded back to a 180-degree angle at a half of its length (13 cm) (see FIG. 7 (2)).

  (5) Hook the free end generated by folding the thermal generator structure 70 on the tension jig of the tensile tester, and fix the end of the acrylic resin plate 15 to which the thermal generator structure 70 is not attached. To do.

  (6) The thermal generator structure 70 is pulled upward at a pulling speed of 50 mm / min, and the thermal generator structure 70 is peeled off from the acrylic resin plate 15.

  (7) The maximum force in the step (6) is defined as the adhesive force of the adhesive layer of the heat generating body structure 70.

(Test Example 2)
The adhesive strength of the adhesive layer of the thermal heating element structure was measured by JIS Z 0237 (adhesive tape / adhesive sheet test method). Three samples were prepared, and the adhesive strength of those adhesive layers was measured. The results are shown in Table 3 as ball numbers.

(Test Example 3)
The use test of the thermal heating element structure was conducted.

  A group of 10 subjects. The breakdown is that 2 people think that they have a lot of hair themselves, 3 people think that they have a little more hair, and 5 people think that they are normal.

  The subjects were asked to apply different thermal heating element structures on the left and right sides of the elbows of both arms, and evaluated whether or not the peeling occurred during use (3 hours) and the pain when peeling.

  Tests were performed on three sets of Invention Example and Comparative Example 1, Invention Example and Comparative Example 2, and Comparative Example 1 and Comparative Example 2.

  The results are shown in Tables 4-6.

  From the results shown in Tables 4 to 6, when the thermal generator structure of the present invention was used, there was almost no problem of peeling during use, and the pain when peeling was the conventional product (Comparative Examples 1 and 2). It is clear that there is a significant improvement over

It is a cross-sectional schematic diagram which shows an example of the heat generating body structure for direct sticking to the skin of this invention. It is a cross-sectional schematic diagram which shows another example of the heat generating body structure for direct sticking to the skin of this invention. It is a schematic diagram which shows an example of the shape of the adhesion layer in the heat generating body structure for direct sticking to the skin of this invention. It is a schematic diagram which shows another example of the shape of the adhesion layer in the heat generating body structure for direct sticking to the skin of this invention. It is a schematic diagram which shows another example of the shape of the adhesion layer in the heat generating body structure for direct sticking to the skin of this invention. It is a schematic diagram which shows another example of the shape of the adhesion layer in the heat generating body structure for direct sticking to the skin of this invention. It is a typical perspective view for demonstrating the measuring method of the adhesive force of an adhesion layer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Breathable sheet layer 3 Heat generating agent composition layer 5 Non-breathable sheet layer 6 Bag body 7 Non-woven fabric layer 9 Adhesive layer 12 Non-woven fabric layer 15 Acrylic resin plate 17 Weight 10, 20, 30, 40, 50, 60, 70 To skin Heat generator structure for direct pasting

Claims (7)

A breathable sheet layer, a heat generating agent composition layer, a non-breathable sheet layer, a nonwoven fabric layer, and an adhesive layer were provided in this order, and the heat generating agent composition layer was formed of a breathable sheet layer and a non-breathable sheet layer. It is a heat generating body structure enclosed inside a bag body, the adhesive layer is partially formed on the nonwoven fabric layer, and the adhesive strength of the adhesive layer is Japanese Pharmacopoeia D-935 ( A thermogenerator structure for direct application to the skin, characterized in that it is 2.80 to 3.50 Newton as measured by the following method in accordance with the test method of Adhesive strength test of adhesive bandage).
(Measurement method of adhesive strength of adhesive layer)
(1) One surface of an acrylic resin plate (9.5 cm or more × 13 cm or more) is wiped with ethanol.
(2) The length of the acrylic resin plate is 9.5 cm or longer on one side of the thermal generator structure (9.5 cm × 13 cm), and one side of 9.5 cm is put on the acrylic resin plate. .
(3) With the thermal generator structure facing down, an 800 g weight is placed on the acrylic resin plate to which the thermal generator structure is affixed, and left in this state at 37 ° C. for 30 minutes.
(4) Fold the thermogen generator structure to a 180-degree angle at a half of its length (13 cm).
(5) Hook the free end generated by folding the thermal generator structure on the tension jig of the tensile tester, and fix the end of the acrylic resin plate to which the thermal generator structure is not attached.
(6) The thermal generator structure is pulled upward at a tensile speed of 50 mm / min, and the thermal generator structure is peeled off from the acrylic resin plate.
(7) The maximum force in the step (6) is defined as the adhesive force of the adhesive layer of the thermal generator structure.   The thermogen generator structure for direct application to the skin according to claim 1, wherein the adhesive strength of the adhesive layer is measured by JIS Z 0237 (adhesive tape / adhesive sheet test method) and has a ball number of 21-30. .   The heat generating body structure for direct application to the skin according to claim 1 or 2, wherein the adhesive layer has a thickness of 20 to 100 µm.   The thermogen generator structure for direct application to the skin according to any one of claims 1 to 3, wherein the total area of the adhesive layer is 20 to 70% of the total area of the application surface.   The thermogen generator structure for direct application to the skin according to any one of claims 1 to 4, wherein the end portions of the adhesive layer are expressed at substantially uniform intervals on each of the four sides of the application surface.   The heat generating body structure for direct application to the skin according to any one of claims 1 to 5, wherein the nonwoven fabric comprises a mixture of hydrophilic fibers and hydrophobic fibers.   Furthermore, the heat generating body structure for direct sticking to the skin of any one of Claims 1 thru | or 6 which has a nonwoven fabric layer in the outer side of a breathable sheet layer.

Images