JP2014121823A - Method for producing heat generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a heat generator, in which delamination of the heat generator is prevented while keeping thermal characteristics thereof.SOLUTION: The method for producing the heat generator comprises: a coating step of forming a heat generator layer 3 on a long belt-like first base material sheet 1 to be conveyed along the longitudinal direction so that an uncoated area 1a is formed in the side edge part of the first base material sheet 1; a sticking step of sticking the heat generator layer-formed first base material sheet 1 to a second base material sheet 4 while interposing the heat generator layer 3 therebetween; and a cutting step of cutting the stuck first base material sheet 1 to the direction perpendicular to the longitudinal direction to form two or more sheets of single wafer-like heat generators 11 disposed in a line; and furthermore an incising step, which is carried out after the sticking step, of forming a plurality of incisions 5 in the uncoated area 1a so that the plurality of incisions are formed respectively on the two or more sheets of single wafer-like heat generators 11 and the first base material sheet 1 and the second base material sheet 4 are bonded to each other.

Description

  The present invention relates to a method for manufacturing a heating element.

2. Description of the Related Art Conventionally, an eye heating tool having a horizontally long eye mask-shaped main body having a shape and size sufficient to cover both eyes when worn has been developed. In this heating device for eyes, the main body has a skin-side sheet, an outer sheet, and a sheet-like heating element disposed between both sheets, and the peripheral portions of the skin-side sheet and the outer sheet are hot-melted to each other. Some of them are joined with an adhesive. Attempts have also been made to facilitate deformation of the sheet-like heating element. For example, what forms the slit extended to one side in multiple lines is disclosed (for example, refer to patent documents 1).
Further, as a method for producing a heating element, a technique has been proposed in which a base material and a covering material are entirely or partially sealed by adhesion, adhesion, or heat fusion at the periphery of the heating element composition ( For example, see Patent Document 2.)

JP 2009-82570 A JP 2003-129041 A

However, slitting the sheet-like heating element is a process for facilitating the deformation itself, and a sufficient binding force cannot be expressed due to moisture contained in the heating element. It is not possible to prevent delamination with the coating material.
Moreover, even if a pressure-sensitive adhesive or adhesive is applied in a state where air permeability is present, air flow inhibition is inevitable. Moreover, when a pressure sensitive adhesive or an adhesive is used for bonding the peripheral portion between the base material and the coating material, the inside of the processing machine may be contaminated with the pressure sensitive adhesive or the adhesive. Moreover, when sealing by heat sealing | fusion, since heat sealing | fusion fiber has hydrophobicity fundamentally, it is inferior to water absorption. For this reason, when the heat-sealing fiber is provided in the covering material, it is difficult to control the moisture inside the heating element by the covering material, and stable thermal characteristics cannot be obtained.
The present invention relates to providing a method for manufacturing a heating element that maintains the thermal characteristics of the heating element and suppresses delamination of the heating elements.

  In the present invention, the heating element layer is applied so that an uncoated region is formed on the side edge of the first base sheet on the first base sheet of the long strip conveyed along the longitudinal direction. A coating step to work, a laminating step for laminating the first base material sheet and the second base material sheet with the heating element layer interposed therebetween, and the pasted first base material sheet intersecting the longitudinal direction And a cutting process for forming a plurality of heating elements for each leaf arranged in a row, each of the plurality of heating elements for each leaf. Heat generation having a cutting process step of forming a plurality of cuts in the uncoated area after the bonding step and joining the first base sheet and the second base sheet so that a plurality of cuts are formed. A method for manufacturing a body is provided.

  According to the heating element manufacturing method of the present invention, delamination of the heating elements can be suppressed.

It is the schematic block diagram which showed typically an example of the manufacturing apparatus of the preferable heat generating body for enforcing the manufacturing method of the heat generating body of this invention. It is process explanatory drawing which showed one Embodiment of the manufacturing method of the heat generating body of this invention. FIG. 1A is a plan view of a main part showing a cutting blade in one embodiment of the present invention, and FIG. 2B is an enlarged sectional view taken along line AA of the cutting blade in FIG.

A preferred embodiment of a method for manufacturing a heating element according to the present invention will be described below with reference to FIGS. 1 and 2.
First, a main part of a heating element manufacturing apparatus suitable for carrying out the heating element manufacturing method will be described with reference to FIGS. 1 and 2.

  As shown in FIGS. 1 and 2, a heating element manufacturing apparatus (hereinafter also referred to as a manufacturing apparatus for short) 20 includes a coating unit 30, an electrolyte addition unit 40, a bonding unit 50, a slit, and a cutting process. Part 60, first cutting part 70, re-pitch part 80, discharge part 90 (flight conveyor 91), and covering part 100.

The coating material 32 adjusted in advance by an adjusting device (not shown) is supplied to the coating unit 30 by a liquid feed pump (not shown).
In the present embodiment, the coating section 30 coats the coating material 32 on the first base sheet 1 of the long strip that is transported along the longitudinal direction fed from the raw roll 1A, and generates a heating element. Layer 3 is applied (coating process).
The coating unit 20 includes a die coater 31 that coats the paint 32. Moreover, the 1st base material sheet 1 of the elongate strip fed from the raw fabric roll 1A is conveyed by the conveyor 33 at a position facing the paint discharge port of the die coater 31, and the die coater 31 is provided on one surface thereof. The coating material 32 is applied, and the coating material layer 2 as the heating element layer 3 is disposed on the one surface. At this time, the coating material 32 is applied so that the uncoated region 1a is formed on the side edge of the first base sheet 1, that is, both edges in the width direction (direction orthogonal to the longitudinal direction) of the first base sheet 1. The paint layer 2 is formed by coating. That is, the coating material 32 is not applied to both edges in the width direction of the first base sheet 1. The uncoated region 1 a may be formed only on either one of the both side edges of the first base sheet 1, and is more preferably formed on both side edges of the first base sheet 1.
When the uncoated region 1a is formed on both side edges of the first substrate sheet 1, the width d of the uncoated region 1a in the width direction is the width W of the first substrate sheet 1 and the width w of the paint layer 2 Then, d = (W−w) / 2. The width d is preferably 1 mm or more, more preferably 2 mm or more, and still more preferably 3 mm or more, from the viewpoint of securing a width for cutting. And from a viewpoint of the heat generation efficiency of the heat generating body manufactured, Preferably it is 15 mm or less, More preferably, it is 10 mm or less, More preferably, it is 5 mm or less. Specifically, it is preferably 1 mm to 15 mm, more preferably 2 mm to 10 mm, and still more preferably 3 mm to 5 mm.

Since a part of the moisture in the paint layer 2 is absorbed by the first base sheet 1, the moisture content of the paint layer 2 is lower than the moisture content in the paint 32. As a result, the fluidity of the paint layer 2 decreases.
As a coating method of the coating material 32, various known coating methods can be used without particular limitation. For example, roll coating, die coating, screen printing, roll gravure, knife coating, curtain coater and the like are used. Die coating is preferred from the viewpoints of ease of application, ease of control of the application amount, and uniformity of the coating film thickness.

In the electrolyte addition unit 40, the electrolyte 41 is dispersed. The powder is used for the electrolyte 41. Moreover, the 1st base material sheet 1 after coating is conveyed by the conveyor 33 from the coating part 30 to the electrolyte addition part 40, and the electrolyte 41 is a coating layer toward the coating surface of the 1st base material sheet 1. 2 to form a heating element layer 3. At this time, the spreading width we of the electrolyte 41 is narrower than the width w of the paint layer 2 and is usually spread narrowly to about 1 mm to 10 mm. Moreover, it is preferable that the width | variety of the area | region where the electrolyte 41 is not spread | dispersed is equal on both sides of the width direction.
The addition of the electrolyte 41 can ensure an electrolyte concentration suitable for heat generation in the heating element layer 3, and the powder electrolyte 41 is dissolved by the moisture contained in the paint layer 2 and the first base sheet 1. The Further, the second base sheet 4 is supplied so as to adhere to the heating element layer 3 side, and is sent to the bonding unit 60. The electrolyte 54 may be an aqueous solution.
Thereby, the water | moisture content in the heat generating body layer 3 is absorbed and hold | maintained at the 2nd base material sheet 4, and the moisture content and electrolyte concentration of the heat generating body layer 3 become suitable.

In the present embodiment, the first base sheet 1 and the second base sheet 4 are bonded together in the bonding section 60 with the heating element layer 3 interposed therebetween (bonding step).
The laminating unit 50 sandwiches the heating element layer 3 produced on the first base sheet 1 by sandwiching it between the conveyor 33 and the nip roll 51 facing the first base sheet 1 and the second base sheet 4. Paste to. The pressure at this time is 4.5 MPa or more, preferably 5.5 MPa or more, more preferably 6 MPa or more, and keeps the uncoated region 1a so that the heating element layer 3 is bonded to both sheets. To 15 MPa or less, preferably 13 MPa or less, more preferably 10 MPa or less. Specifically, it is 4.5 MPa or more and 15 MPa or less, preferably 5.5 MPa or more and 13 MPa or less, more preferably 6 MPa or more and 10 MPa or less. The 1st base material sheet 1 which bonded the 2nd base material sheet 4 via the heat generating body layer 3 in the bonding part 50 is sent to the slit and the cutting process part 60. FIG.

In the present embodiment, in the slit and incision processing part 60, a plurality of incisions are formed in the uncoated region 1a, and an incision processing step for joining the first base sheet 1 and the second base sheet 4 is performed.
The slit / slicing unit 60 is configured to produce the slit 5 (perforation) and the slit 6 in the longitudinal direction of the first base sheet 1, that is, in the transport direction of the first base sheet 1. The cut 5 is arranged in the uncoated area 1a. The slit 6 is disposed at a position that divides the heating element layer 3 into two in the width direction. Moreover, it is preferable that the space | interval in the longitudinal direction of the 1st base material sheet 1 of the notch 5 is equal intervals so that the joining force of the sheets by the notch 5 may not change. Such equally spaced cuts 5 may be made with perforations.

Next, the incision in the incision process (perforation process) will be described with reference to FIG.
The cutting blade (not shown) used for the cutting process will be described in detail later. A slitter blade with a continuous blade arranged on the outer periphery of the disk is formed with a gap at equal intervals, and a slitter blade at an equal interval on the outer periphery of the disk. The cutting blade was produced by leaving
In order to produce the cut 5 in the uncoated region 1a in which the first base sheet 1 and the second base sheet 4 are combined using the cutting blade, the first base sheet 1 side is rotated while rotating the disk. The cut is pressed against the anvil roll 62 as a receiving member with the uncoated region 1a interposed therebetween. As a result, the portion of the first base sheet 1 that is in contact with the cutting blade is pushed into the second base sheet 4, and the portion of the second base sheet 4 that is pushed in the first base sheet 1 is the first base sheet 1. The portion of the first base sheet 1 and the second base sheet 4 that are extruded to the side opposite to the material sheet 1 side and extruded by the cutting blade are mechanically joined. At this time, the first base sheet 1 is directly pressed by the cutting blade, but the second base sheet 4 is pressed through the first substrate sheet 1. For this reason, since the 2nd base material sheet 4 is spread more widely than the 1st base material sheet 1 by the cutting blade, the force with which the expanded part tries to return becomes stronger in the 2nd base material sheet 4. Since the force of the second base sheet 4 to return exceeds the force of the first base sheet 1 to return, the first base sheet 1 and the second base sheet 4 are joined. Therefore, mechanical joining means joining by the frictional force by contact of sheets. In addition, the joining may include the joining by the fibers entangled with each other.
Accordingly, as long as the first base sheet 1 and the second base sheet 4 are joined to the uncoated region 1a by the notch 5, either the through-hole is opened or not opened by the notch blade. Good.
In addition, the second base sheet 4, the heating element layer 3, and the first base sheet 1 are cut together by the slitter blade 210 at the center in the width direction.

Since the cutting blade is rotating, each blade of the cutting blade is pressed against the first base material sheet 1 in order, and the first base material sheet 1 and the second base material sheet 4 are matched with each other. Cuts 5 are produced at equal intervals in the uncoated region 1a.
In the present embodiment, a cut 5 may be provided in the heating element layer coating region (heating element layer 3) for the purpose of improving the flexibility of the heating element. The intervals of the notches 5 may be equal intervals, or the intervals may be regularly narrowed or widened. The notch 5 is produced in the heating element layer 3, and the production method of the notch 5 is the same as the above except that the depth of pressing of the blade is adjusted, and the notching blade is pressed against the heating element layer 3. Thus, the notch 5 is formed in the heating element layer 3.
Furthermore, the slit 6 is produced by cutting with a blade 210 in which a continuous blade is arranged on the outer periphery of the disk.

  In the present embodiment, perforations are formed so that the perforated cuts, that is, the arrangement direction of the plurality of cuts 5 and the direction in which each cut 5 itself extends coincide with each other. Moreover, the shape of the notch | incision 5 may be another shape, if the 1st base material sheet 1 and the said 2nd base material sheet 4 are joined. For example, it may have a cut shape in which cuts extending in a direction perpendicular to the longitudinal direction of the first base sheet 1 are arranged side by side in the longitudinal direction. From the viewpoint of forming cuts in the non-coating region 1a, a cut shape in which the arrangement direction of the plurality of cuts and the direction in which each cut extends extends is preferable.

As shown in FIG. 3, the cutting blade 200 for producing the above-described cut 5 is formed with gaps 203 at equal intervals in a slitter blade 202 in which continuous blades are arranged on the outer periphery of the disk 201. The slitting blades 204 are produced by leaving the slitter blades 202 at equal intervals on the outer periphery. The cross-sectional shape in the thickness direction of the cutting blade 204 is a triangle having a rounded tip, and preferably an isosceles triangle having a rounded tip. The roundness radius R of the tip is preferably 1 mm or less, more preferably 0.5 mm or less, and still more preferably 0.3 mm or less, from the viewpoint of easy sticking to the sheet. Moreover, the angle θ of the cutting edge of the cross section in the thickness direction is preferably 5 ° or more, more preferably 10 ° or more, and still more preferably, from the viewpoint of the bondability between the first base sheet 1 and the second base sheet 4. It is 15 ° or more, and preferably 60 ° or less, more preferably 50 ° or less, and further preferably 45 ° or less. The thickness t of the cutting blade 204 is preferably 10 mm or less, more preferably 5 mm or less, and even more preferably 3 mm or less. Further, the circumferential length L of the cutting blade 204 is preferably 0.5 mm or more, more preferably 1 mm or more, further preferably 3 mm or more, and preferably 15 mm or less, more preferably 10 mm or less, and still more preferably. 5 mm or less. Further, the circumferential interval dc (the length in the circumferential direction of the gap 203) of the cutting blade 204 is preferably 0.3 mm or more, more preferably 0.5 mm or more, further preferably 1 mm or more, and preferably It is 15 mm or less, More preferably, it is 10 mm or less, More preferably, it is 3 mm or less.
As a preferable example, the cutting blade 200 is an isosceles triangle having a rounded radius R of the tip of 0.1 mm and an angle θ of the blade edge of 45 °, the thickness t of the cutting blade 204 is 2.1 mm, and the length in the circumferential direction of the blade. The length L is 3 mm and the interval dc is 1 mm.

In the cutting process of the present embodiment, it is preferable to perform the cutting process so that a plurality of cuts are formed in each heating element 11 of each leaf formed in the cutting process described later. The number of cuts varies depending on the length of the heating element 11 and the length of the cut. For example, when a notch having a length of 3 mm is arranged for a heating element 11 having a length of 49 mm, the number of incisions formed along one side edge of each heating element 11 is preferably 5 or more. More preferably, it is 10 or more, Especially preferably, it is 12 or more. Since the effect of bonding increases as the number of cuts increases, there is no particular upper limit to the number of cuts, but the interval dc is also defined as described above so as not to cut from the cut.
The total length of the cuts is preferably 50% or more, more preferably 65% or more, and preferably 90% or less, more preferably 85% or less of the length of the heating element. Further, when the cuts are arranged at equal intervals, the ratio between the cut and the relief (between the cut and the cut) is 1: 1 to 10: 1, more preferably 2: 1 to 5: 1.

  In this way, as shown in FIGS. 1 and 2, a heating element continuous body 10 made of a continuous long object is produced. Thereafter, the heating element continuous body 10 is cut in the first cutting portion 70 in a direction (width direction) intersecting the longitudinal direction (cutting step). The 1st cutting part 70 is provided with the rotary die cutter 72 and the anvil roll 73 which have the blade 71 of a cutter on a surrounding surface. The heating element continuous body 10 is cut by passing between the rotary die cutter 72 and the anvil roll 73, and a plurality of heating elements 11 are obtained for each leaf. The cut heating element 11 is transferred to the re-pitch unit 80 and received by the conveyor 81.

  The cutting of the heating element continuous body 10 is performed in the width direction of the heating element continuous body 10. For example, it can be performed linearly across the width direction of the heating element continuum 10. Or it can cut so that a cutting line may draw a curve.

The heating element 11 that has become a leaf is placed on the conveyor belt 52 of the conveyor 81 disposed in the re-pitch section 80. The conveyance speed of the conveyance belt 52 is faster than the peripheral speed of the anvil roller 73 installed in the first cutting unit 70. As a result, the distance between the heating elements 11 adjacent to each other in the transport direction increases, and the heating elements 10 are rearranged at a predetermined distance.
Normally, the conveyor 81 conveys the heating element 11 while sucking it toward the conveyor 81 side. In conveying the heating element 11 in the next flight conveyor 91, the suction of the latter stage of the conveyor 81 may be stopped in order to prevent the heating element 11 from falling before the flight conveyor 91. Moreover, in the said conveyor 81, the space | interval of the width direction of the heat generating body 11 is also expanded.
As such a re-pitch mechanism, a conventionally known one can be used without particular limitation. Note that front and rear in the transport direction mean upstream and downstream in the transport direction.

The heating element 11 that is re-pitched and widened in the width direction is conveyed to the discharge unit 90. The discharge unit 90 is provided with a flight conveyor 91.
The flight conveyor 91 has a plurality of rollers arranged so that the rotation axes thereof are parallel to each other, and an endless belt 93 that is stretched between the rollers 92. The endless belt 93 is configured to circulate in the direction of the arrow in FIG. The circumferential track of the endless belt 93 has, in part, a portion 93a where the support surface of the conveyed object faces downward in the vertical direction. The heating element 11 is conveyed through this portion 93a. That is, the heating element 10 is conveyed in a suspended state. In order to realize conveyance in such a state, a suction box 94 is installed inside the circular orbit at the position of the portion 93a facing downward. Further, the endless belt 93 is provided with a through hole (not shown). Thus, when the suction box 94 is activated, air is sucked from the outside to the inside of the circuit track through the through hole. By this suction, the heating element 11 that is a transported object is transported through the portion 93 a while being supported by suction on the support surface of the endless belt 93.

Conveying the heating element 11 in a suspended state is advantageous when the flight conveyor 91 is used as a defective product discharging apparatus. Specifically, a defect detection sensor (not shown) is arranged at any position upstream of the flight conveyor 91. And the defect of the heat generating body 10 is detected by this sensor. A discharge point is provided in the portion 93a, and when the detected defective product reaches the discharge point in the flight conveyor, the suction of air by the suction box 93 at the discharge point is switched to the blowing. As a result, the defective product can be dropped and easily discharged from the production line.
The suction force of the suction box 94 is preferably 50 Pa or more, more preferably 100 Pa or more, and further preferably 200 Pa or more so as not to drop the heating element 11. And from a viewpoint that the heat generating body 11 sticks to a conveyor belt and does not make it wind up, Preferably it is 10 kPa or less, More preferably, it is 8.0 kPa or less, More preferably, it is 6.0 kPa or less. Specifically, it is preferably 50 Pa or more and 10 kPa or less, more preferably 100 Pa to 8.0 kPa, and even more preferably 200 Pa to 6.0 kPa.
Further, since the heating element 11 is small, the delivery between the conveyor 81 and the conveyor 101 becomes unstable. However, the heating element 11 can be stably delivered from the conveyor 81 to the conveyor 101 via the flight conveyor 91. .

  Since the cut 5 is given to the uncoated area | region 1a which match | combined the 1st base material sheet 1 and the 2nd base material sheet 4 when conveyed with the flight conveyor 91, even from the 2nd base material sheet 4 Even if the heating element layer 3 is peeled off, it is supported by the first base material sheet 1 joined to the second base material sheet 4 by the notch 5, and the falling off of the heating element layer 3 and the first base material sheet 1 is suppressed. be able to. Moreover, even if the 1st base material sheet 1 peels from the heat generating body layer 3, since the 1st base material sheet 1 is joined to the 2nd base material sheet 4 similarly, drop-off | omission of the base material sheet 1 is suppressed. can do.

The heating element 11 that has passed through the discharge unit 90 is delivered to the conveyor 101 of the covering unit 100. The covering portion 100 covers the entire heating element 11 with the first covering sheet 12 and the second covering sheet 13.
The first covering sheet 12 is disposed on the side of the heating element 11 on which the heating element layer 3 is disposed to cover the heating element 11. On the other hand, the second covering sheet 13 is supplied by the conveyor 101 provided in the covering unit 100. Then, the heating conveyor 11 is arranged on the second covering sheet 13 on the conveyor 101 by the flight conveyor 91, and the side of the heating element 11 where the heating element layer 3 is not arranged is covered with the second covering sheet 13. And the heat generating body 11 coat | covered with the conveyor 101 is conveyed to the sealing part 110 shown in FIG. 2, maintaining the covering state by the 1st cover sheet 12 and the 2nd cover sheet 13. FIG.

The sealing portion 110 includes a first roll 112 having seal protrusions (not shown) at equal intervals on the peripheral surface and parallel to the width direction, and seal protrusions at equal intervals on the peripheral surface and parallel to the width direction. And a second roll 112 having (not shown). The first and second rolls 111 and 112 have their axial directions parallel to each other, the seal projections of both rolls abut against each other, and a predetermined clearance is generated between the first and second rolls 111 and 112. They are arranged in such a positional relationship.
In the sealing part 110, the 1st coating sheet 12 supplied from the one surface side of the heat generating body 11 and the 2nd coating sheet 13 supplied from the other surface side are joined by a seal convex part. This bonding includes heat fusion, thermocompression bonding, ultrasonic bonding, bonding with an adhesive, and the like. Even if the airtight bonding is continuous so as to surround the heating element 11, it is a discontinuous bonding surrounding the heating element 11. May be.

  Each heating element 11 is continuously covered with the first covering sheet 12 and the second covering sheet 13 by the sealing portion 110, and a heating element continuous body 14 in which a plurality of heating elements are connected in one direction is obtained. . As the 1st covering sheet 12 and the 2nd covering sheet 13, the thing similar to what was indicated in JP, 2012-000344, A JP, 2012-000345, A, etc. can be used, for example. In a 2nd cutting part (not shown), the heat generating tool continuous body 14 is cut | disconnected over the width direction between the adjacent heat generating bodies 11. FIG. The 2nd cutting part is provided with the rotary die cutter and the anvil roll which counters it. Cutting is performed by passing the heating tool continuum 14 between the two members, whereby a target heating tool (not shown) is obtained.

  In this way, this heating tool is hermetically housed in a packaging bag having oxygen barrier properties in the next step (not shown).

Next, the raw material of the paint 32 will be described in detail.
Examples of the oxidizable metal include powders of iron, aluminum, zinc, manganese, magnesium, calcium, and the like. Preferably, iron powder is used.
The particle size of the iron powder is preferably 0.1 μm or more and 300 μm or less, more preferably 0.1 μm or more and 200 μm or less, more preferably 0.1 μm or less from the viewpoint that the oxidation reaction of the iron powder is efficiently performed. 1 μm or more and 150 μm or less. The iron powder preferably contains 50% by mass or more of particles having a particle size of 0.1 μm or more and 300 μm or less, more preferably 0.1 or more and 200 μm or less, and further preferably 0.1 μm or more and 150 μm or less. To do. In the present specification, “particle size” refers to an average particle size measured by a dynamic light scattering method, a laser diffraction method, or the like, for example, an average particle size measured by a particle size distribution measuring device manufactured by Shimadzu Corporation.

  As the reaction accelerator, one that has a function of at least one of an oxygen retention agent and an oxygen supply agent for the oxidizable metal in addition to acting as a moisture retention agent is used. For example, activated carbon, carbon black, acetylene black, graphite, zeolite, perlite, vermiculite, silica and the like can be mentioned. From the viewpoint that water can be efficiently retained even with a small number of added parts, activated carbon is preferably used.

  Examples of the thickener include guar gum, xanthan gum, roast bean gum, carrageenan, agar, and hydroxymethylcellulose. Xanthan gum is preferably used from the viewpoint of being stable in various environments.

  As the electrolyte, an electrolyte capable of dissolving an oxide formed on the surface of the oxidizable metal particles is used. Examples thereof include sulfates, carbonates, chlorides or hydroxides of alkali metals, alkaline earth metals or transition metals. Among these, chlorides of alkali metals, alkaline earth metals, or transition metals are mentioned because they are excellent in conductivity, chemical stability, and production cost. In particular, chlorides of alkali metals such as sodium chloride and potassium chloride, chlorides of alkaline earth metals such as calcium chloride and magnesium chloride, ferrous chloride, ferric chloride and the like can be mentioned.

The amount of the raw material is, for example, from 1 part to 20 parts, preferably from 1 part to 18 parts, more preferably from 2 parts to 14 parts, based on 100 parts of the oxidizable metal particles. Includes: Water contains 25 parts or more and 85 parts or less, preferably 30 parts or more and 80 parts or less, and more preferably 35 parts or more and 75 parts or less. Moreover, when mix | blending a thickener, 0.05 part or more and 10 parts or less, Preferably it is 0.07 part or more and 8 parts or less, More preferably, 0.1 part or more and 5 parts or less are included. Further, when a surfactant is blended, 0.1 part or more and 15 parts or less, preferably 0.15 part or more and 12 parts or less, and more preferably 0.2 part or more and 10 parts or less.
Further, water is contained in an amount of 18% by mass to 48% by mass, preferably 20% by mass to 45% by mass, and more preferably 23% by mass to 43% by mass, assuming that the total mass of the paint is 100%.
The viscosity of the coating is 0.5 Pa · s to 30 Pa · s, preferably 0.75 to 25 Pa · s, more preferably 1 to 15 Pa · s in an air atmosphere at 23 ° C. and 50 RH. For measurement of the viscosity, a B-type viscometer No. 4 rotor (manufactured by Tokyo Keiki) was used.

The amount of the oxidizable metal in the heating element layer 3 is 100 g / m ² or more and 3000 g / m ² or less, particularly 200 g / m ² or more and 1500 g / m ² or less in terms of basis weight. From the viewpoint of securing
The amount of the reaction accelerator in the heating element layer 3 is 4 g / m ² or more and 80 g / m ² or less, particularly 8 g / m ² or more and 50 g / m ² or less, from the viewpoint of maintaining stable heat generation for a long time. To preferred.
For the same reason, the amount of the electrolyte in the heating element layer 3 is preferably 4 g / m ² or more and 40 g / m ² or less, more preferably 5 g / m ² or more and 30 g / m ² or less.
These basis weights are values when the heating element layer 3 is formed on one side of the base sheet 1. Further, the basis weight is appropriately adjusted according to the specific application of the heating element 11.

  The amount of electrolyte added (in terms of solid content) is 0.5 parts or more and 15 parts or less, preferably 0.75, with respect to 100 parts of the oxidizable metal particles added in the same coating area as described above. Part to 12 parts, more preferably 1 part to 10 parts.

  As the 1st base material sheet 1 and the 2nd base material sheet 4, the fiber sheet containing a hydrophilic fiber can be used, for example. The fiber sheet may contain superabsorbent polymer particles. As the superabsorbent polymer, a three-dimensional crosslinked polymer that can absorb and retain water to form a hydrogel can be used.

  The first and second substrate sheets 1 and 4 made of fiber sheets can be, for example, (a) one sheet in which the superabsorbent polymer particles and hydrophilic fibers are uniformly mixed. The first and second base sheets 1 and 4 are (b) particles of the superabsorbent polymer are mainly present in a substantially central region in the thickness direction of the base sheet, and on the surface of the base sheet. May be of one ply having a structure in which the particles are substantially absent. Further, the first and second substrate sheets 1 and 4 are (c) a laminate of two fiber sheets in which particles of superabsorbent polymer are arranged between the same or different fiber sheets containing hydrophilic fibers. But it can be. Of these base sheets that can take various forms, it is preferable to use the base sheet having the form (b) from the viewpoint of easily controlling the moisture content of the layer of the heat generating composition.

As the hydrophilic fiber contained in the first base sheet 1 and the second base sheet 4 made of fiber sheets, any of natural fibers and synthetic fibers can be used. By using hydrophilic fibers as the constituent fibers of the first and second substrate sheets 1 and 4, hydrogen bonds are easily formed between the oxidizable metal powders contained in the layer of the heat generating composition, and the heat generating composition. There is an advantage that the shape retention of the object layer is improved. Further, the use of the hydrophilic fiber also has the advantage that the water absorption or water retention of the first and second substrate sheets 1 and 4 is improved, and the moisture content of the layer of the heat generating composition can be easily controlled. From these viewpoints, cellulose fibers are preferably used as the hydrophilic fibers. Chemical fibers (synthetic fibers) and natural fibers can be used as the cellulose fibers.
As chemical fibers of cellulose, for example, rayon and acetate can be used. On the other hand, various vegetable fibers such as wood pulp, non-wood pulp, cotton, hemp, wheat straw, hemp, jute, kapok, palm, rush and the like can be used as the natural cellulose fiber. Of these cellulose fibers, it is preferable to use wood pulp from the viewpoint that a thick fiber can be easily obtained. The use of thick fibers as the cellulose fibers is advantageous from the viewpoints of water absorption or water retention of the base sheet, retention of the heat generating layer, and the like.
The above-mentioned various hydrophilic fibers have a fiber length of preferably 0.5 mm or more, more preferably 0.8 mm or more, and preferably 6 mm or less, more preferably 4 mm or less. It is preferable from the viewpoint of easy production of a substrate sheet by a dry method.

  In addition to the above-mentioned hydrophilic fibers, the first and second base sheets 1 and 4 may contain heat-fusible fibers as necessary. By blending this fiber, the strength of the substrate sheet in a wet state can be increased. The blending amount of the heat-fusible fiber is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and preferably 10% by mass or less, based on the total amount of fibers in the base sheet. More preferably, it is 5 mass% or less.

  At least one of the first base sheet 1 and the second base sheet 4 made of a fiber sheet may contain particles of a superabsorbent polymer as described above. In the above-described embodiment, it is preferable that the second base sheet 4 includes particles of the superabsorbent polymer, and the first base sheet 1 does not include the superabsorbent polymer. The location of the superabsorbent polymer particles in the second base sheet 4 is as described above.

  As the superabsorbent polymer, it is preferable to use a hydrogel material that can absorb and retain a liquid having a weight 20 times or more of its own weight and can gel. The shape of the particles can be spherical, massive, grape bunches, fibers and the like. The particle diameter of the particles is preferably 1 μm or more, more preferably 10 μm or more, and preferably 1000 μm or less, more preferably 500 μm or less. Specific examples of superabsorbent polymers include starch, crosslinked carboxylmethylated cellulose, polymers or copolymers of acrylic acid or alkali metal acrylates, polyacrylic acid and salts thereof, and polyacrylate graft polymers. Is mentioned. The superabsorbent polymer particles are preferably bonded to the fiber material contained in the base sheet. For the joining, for example, the viscosity generated by wetting the particles of the superabsorbent polymer can be used. Also, using a superabsorbent polymer particle formed by adhering a liquid material containing either one or both of a polymerizable monomer and a polymerized product of the monomer to a web made of a fiber material and polymerizing it. But you can. The particles of the superabsorbent polymer are bonded to the fiber material.

The proportion of the superabsorbent polymer in each base sheet is preferably 10% by mass or more, more preferably 20% by mass or more, and preferably 70% by mass or less, more preferably 55% by mass or less. However, it is preferable from the viewpoint of making the water absorption or water retention of the base sheet suitable and controlling the moisture content of the heat generating layer. In addition, this ratio is the value measured about this base material sheet in a dry state before the heat generating body layer 3 is formed on a base material sheet.
The basis weight of the first base sheet 1 and the second base sheet 4 is preferably 10 g / m ² or more, more preferably 20 g / m ² or more, and preferably 200 g / m ² or less, more preferably. It is 160 g / m ² or less. By setting the basis weight of the first and second substrate sheets 1 and 4 within this range, the strength of the first and second substrate sheets 1 and 4 in a wet state can be sufficiently secured, and The water absorption or water retention of the first and second substrate sheets 1 and 4 can be made suitable. On the other hand, the basis weight of superabsorbent polymer contained in the first, second base sheet 1 and 4, preferably more preferably 5 g / ^{m 2} and at 10 g / ^{m 2} or more, preferably 150 g / ^{m 2} Hereinafter, it is more preferably 100 g / m ² or less. By setting the basis weight of the superabsorbent polymer within this range, the water absorption or water retention of the first and second substrate sheets 1 and 4 can be further improved. Moreover, it becomes easier to control the moisture content of the heat generating layer. These basis weights were measured for the first and second substrate sheets 1 and 4 in a dry state before the layer of the heat generating composition was formed on the first and second substrate sheets 1 and 4. Value.

  When a sheet containing a superabsorbent polymer is used for either the first base sheet 1 or the second base sheet 4, the sheet containing the superabsorbent polymer is used as the support surface of the flight conveyor 91. It is preferable to carry it with suction support. The moisture in the heating element layer 3 tends to be heavier because it is more easily absorbed by the sheet containing the superabsorbent polymer than the sheet not containing the superabsorbent polymer. Therefore, if the sheet containing the superabsorbent polymer is sucked and supported, peeling during conveyance by the flight conveyor 91 is further suppressed.

  Moreover, a film, a nonwoven fabric, and paper can also be used for any one of the 1st base material sheet 1 and the 2nd base material sheet 4. FIG. For example, fiber sheets, such as a synthetic resin film and a nonwoven fabric, can be used. As the polymer material of the synthetic resin film, polyethylene, polypropylene, nylon, polyester, polyvinyl chloride, and the like can be used, and the synthetic fiber of the same material can also be used for the nonwoven fabric.

From the viewpoint that the heat generating element 11 finally obtained can exhibit the desired heat generation, the water content of the heat generating element 11 is preferably 5 mass% or more and 40 mass% or less, more preferably 7.5. It is preferable to carry out so that it may become mass% or more and 30 mass% or less, More preferably, it is 10 mass% or more and 25 mass% or less. In order to make the moisture content of the heat generating body 11 into the above range, it can be realized by adjusting the nip pressure in the bonding step. Specifically, by increasing the nip pressure, moisture can be forcibly transferred to the base sheet side and the moisture content of the heating element 11 can be reduced.
In order to obtain such a moisture content, the moisture content of the entire sheet including the first substrate sheet 1, the second substrate sheet 4 and the heating element layer 3 is preferably 20% by mass or more, more preferably 25% by mass. % Or more, more preferably 30% by mass or more, and preferably 60% by mass or less, more preferably 50% by mass or less, and further preferably 40% by mass or less. Specifically, it is preferably 20% by mass or more and 60% by mass or less, more preferably 25% by mass or more and 50% by mass or less, and further preferably 30% by mass or more and 40% by mass or less.

The moisture content of the entire sheet including the first substrate sheet 1, the second substrate sheet 4 and the heating element layer 3 is measured by measuring the mass of the entire sheet in a nitrogen environment, and then at 105 ° C. in a vacuum state. It puts in the drying oven of temperature for 2 hours, removes moisture, measures the mass again, and calculates the water content with the difference mass as the moisture content.
The moisture content of the heating element described above is a value when one heating element layer 3 is formed on the first base sheet 1, but the heating element layer 3 is provided on each surface of the first base sheet 1. Even when formed, it is preferable to satisfy the above-mentioned range.
The moisture content of the heating element layer 3 was determined by peeling only the heating element layer 3 from the base material sheet in a nitrogen environment, measuring its mass, and then placing it in a drying oven at a temperature of 105 ° C. in a vacuum state for 2 hours. Is removed, the mass is measured again, and the moisture content is calculated using the difference mass as the moisture content.

Further, the coating basis weight of the coating 32 is preferably 150 g / ^{m 2} or more, more preferably 200 g / ^{m 2} or more, more preferably set to 300 g / ^{m 2} or more, and preferably 4600g / ^{m 2} or less, more preferably 3000 g / ^{m 2} or less, and more preferably 2200 g / ^{m 2} or less. Specifically, preferably 150 g / ^{m 2} or more 4600g / ^{m 2} or less, more preferably 200 g / ^{m 2} or more 3000 g / ^{m 2} or less, more preferably to 300 g / ^{m 2} or more 2200 g / ^{m 2} or less.

The heating tool manufactured in this way is applied directly to the human body or applied to clothing, and is suitably used for warming the human body. Examples of the application site in the human body include the shoulder, neck, eyes, waist, elbow, knee, thigh, lower leg, abdomen, lower abdomen, hands, and soles. Further, in addition to the human body, the present invention is applied to various articles and suitably used for heating and keeping warm.
Moreover, the said heat generating body 11 can also be used for the heat generating part of another structure other than the heat generating part of the heat generating tool 14, and another use. When used for warming the human body, the first covering sheet 12 that generates water vapor is applied toward the skin side (human body side).

  In addition to the above-described embodiments and implementations, the following additional notes are disclosed.

<1> The heating element layer is coated on the first base sheet of the long strip transported along the longitudinal direction so that an uncoated region is formed on the side edge of the first base sheet. Coating process to
A laminating step of laminating the first base material sheet and the second base material sheet with the heating element layer interposed therebetween;
Cutting the pasted first base sheet over the direction intersecting the longitudinal direction, and forming a plurality of heating elements of each leaf arranged in a row,
A method of manufacturing a heating element having
The first substrate sheet and the second substrate are formed by forming a plurality of cuts in the uncoated region after the bonding step so that a plurality of cuts are formed in each of the plurality of heating elements of each leaf. The manufacturing method of the heat generating body which has the cutting process process which joins a sheet | seat.
<2> The method for manufacturing a heating element according to <1>, wherein the plurality of cuts are arranged side by side in the longitudinal direction of the first base sheet.
<3> The width in the direction intersecting the longitudinal direction of the uncoated region is preferably 1 mm or more, more preferably 2 mm or more, further preferably 3 mm or more, preferably 15 mm or less, more preferably 10 mm or less, More preferably, the heating element manufacturing method according to <1> or <2>, which is 5 mm or less.
<4> In any one of <1> to <3>, in the bonding step, the first base sheet and the second base sheet are bonded by passing between a pair of opposing nip rolls. A method for manufacturing a heating element.
<5> The nip pressure of the nip roll is 4.5 MPa or more, preferably 5.5 MPa or more, more preferably 6 MPa or more, 15 MPa or less, preferably 13 MPa or less, more preferably 10 MPa or less. Method for producing a heating element.
<6> In the cutting process, the bonded first base sheet and second base sheet are divided into two parts by forming slits in a direction perpendicular to the longitudinal direction. <1> to <5> The manufacturing method of the heat generating body of any one.
<7> The method for manufacturing a heating element according to any one of <1> to <6>, wherein in the cutting process step, a cut is provided in the coated heating element layer.
<8> In the incision processing step, the cutting blades arranged at equal intervals on the outer periphery of the disk are pressed against the receiving member with the uncoated region in which the first base material sheet and the second base material sheet are combined. The method for manufacturing a heating element according to any one of <1> to <7>, wherein a plurality of cuts are formed in the uncoated region by applying.
<9> In the cutting process, by pressing the cutting blade against the receiving member, the portion of the first base sheet in contact with the cutting blade can be pressed into the second base sheet, and the first The second base sheet in the portion into which the base sheet is pushed is pushed out to the side opposite to the first base sheet side, and the first base sheet and the second base in the portion pushed out by the cutting blade. The method for manufacturing a heating element according to <8>, wherein the material sheet is mechanically joined.
<10> The method for manufacturing a heating element according to <8> or <9>, wherein the receiving member is an anvil roll.
<11> The cutting blade is a slitter blade having a continuous blade arranged on the outer periphery of the disk, creating gaps at equal intervals, and leaving the slitter blades at equal intervals on the outer periphery of the disk. <8> to <10> according to any one of <8> to <10>.
<12> The cross-sectional shape in the thickness direction of the cutting blade is a triangle having a rounded tip, and preferably an isosceles triangle having a rounded tip. The roundness radius R of the tip is preferably 1 mm or less, more preferably 0.5 mm or less, and even more preferably 0.3 mm or less, for ease of sticking to the sheet, and any one of <8> to <11> Method for producing a heating element.
<13> The angle θ of the cutting edge of the cross section in the thickness direction of the cutting blade is preferably 5 ° or more, more preferably 10 ° or more, still more preferably 15 ° or more, and preferably 60 ° or less, more preferably Is 50 ° or less, more preferably 45 ° or less, The method for producing a heating element according to any one of <8> to <12>.
<14> The method for manufacturing a heating element according to any one of <8> to <13>, wherein a thickness t of the cutting blade is preferably 10 mm or less, more preferably 5 mm or less, and further preferably 3 mm or less.
<15> The circumferential length L of the cutting blade is preferably 0.5 mm or more, more preferably 1 mm or more, further preferably 3 mm or more, and preferably 15 mm or less, more preferably 10 mm or less, The method for producing a heating element according to any one of <8> to <14>, which is preferably 5 mm or less.
<16> The circumferential distance dc between the cutting blades is preferably 0.3 mm or more, more preferably 0.5 mm or more, still more preferably 1 mm or more, and preferably 15 mm or less, more preferably 10 mm or less, More preferably, the heating element manufacturing method according to any one of <8> to <15>, which is 3 mm or less.
<17> The method for manufacturing a heating element according to any one of <1> to <16>, wherein a plurality of cuts are formed in each of the plurality of heating elements of each leaf formed in the cutting step.
<18> The number of cuts formed side by side on one side edge of the heating element is preferably 5 or more, more preferably 10 or more, and particularly preferably 12 or more. Any one of <1> to <17> A method for producing the heating element according to claim 1.
<19> The total length of the cuts is preferably 50% or more, more preferably 65% or more, and preferably 90% or less, more preferably 85% or less of the length of the heating element <17> or The manufacturing method of the heat generating body as described in <18>.
<20> When the cuts are arranged at equal intervals, the ratio of the cuts to the reliefs is 1: 1 to 10: 1, more preferably 2: 1 to 5: 1. Any of <17> to <19> A method for producing the heating element according to claim 1.
<21> The method for manufacturing a heating element according to any one of <1> to <20>, wherein the uncoated region is formed on both side edges of the first base sheet.
<22> The method for manufacturing a heating element according to any one of <1> to <21>, wherein the notch has a perforated shape.
<23> After the cutting step, the endless belt with the support surface facing downward in the vertical direction supports the plurality of heating elements of each leaf, and the endless belt circulates so that the plurality of sheets of each leaf <1> to <22> The method for producing a heating element according to any one of <1> to <22>, further comprising a step of conveying the heating element.
<24> The method for manufacturing a heating element according to <23>, wherein the heating element is supported by suction from a through hole provided in the endless belt.
<25> The suction force for sucking the heating element is preferably 50 Pa or more, more preferably 100 Pa or more, more preferably 200 Pa or more, preferably 10 kPa or less, more preferably 8.0 kPa or less, and even more preferably. The manufacturing method of the heat generating body as described in <24> which is 6.0 kPa or less.
<26> The method for manufacturing a heating element according to any one of <1> to <25>, wherein the heating element layer contains an oxidizable metal.
<27> The method for manufacturing a heating element according to <26>, wherein the metal to be oxidized is iron powder.
<28> The average particle diameter of the iron powder is 0.1 μm or more and 300 μm or less, more preferably 0.1 μm or more and 200 μm or less, and further preferably 0.1 μm or more and 150 μm or less. A method for manufacturing a heating element.
<29> The average particle size of the iron powder is preferably 0.1 μm or more and 300 μm or less, more preferably 0.1 μm or more and 200 μm or less, and further preferably 0.1 μm or more and 150 μm or less. The method for producing a heating element according to <27> or <28>, containing 50% by mass or more.
<30> The method for manufacturing a heating element according to any one of <1> to <29>, wherein the heating element layer is formed by applying a paint on the first base sheet.
<31> The coating material contains a reaction accelerator and an oxidizable metal, and the reaction accelerator is 1 part or more and 20 parts or less, preferably 1 part or more and 18 parts per 100 parts of the oxidizable metal particles. Part or less, more preferably 2 parts or more and 14 parts or less, <26> or <29>.
<32> The method for producing a heating element according to <31>, wherein the reaction accelerator is activated carbon.
<33> The paint contains a thickener and is 0.05 to 10 parts, preferably 0.07 to 8 parts, and more preferably 0 to 100 parts of the oxidizable metal particles. The manufacturing method of the heat generating body as described in <31> or <32> which is 1 part or more and 5 parts or less.
<34> The method for producing a heating element according to <33>, wherein the thickener is xanthan gum.
<35> The coating material contains a surfactant and is from 0.1 part to 15 parts, preferably from 0.15 parts to 12 parts, more preferably from 100 parts of the oxidizable metal particles. The method for manufacturing a heating element according to any one of <31> to <34>, which is 0.2 part or more and 10 parts or less.
<36> The paint contains water, and is 25 parts or more and 85 parts or less, preferably 30 parts or more and 80 parts or less, more preferably 35 parts or more and 75 parts or less, with respect to 100 parts of the oxidizable metal particles. The method for producing a heating element according to any one of <31> to <35>.
<37> The water is 18% by mass to 48% by mass, preferably 20% by mass to 45% by mass, and more preferably 23% by mass to 43% by mass, assuming that the total mass of the paint is 100%. A method for producing a heating element according to <36>.
<38> The viscosity of the paint is 0.5 Pa · s to 30 Pa · s in an air atmosphere of 23 ° C. and 50 RH, preferably 0.75 Pa · s to 25 Pa · s, more preferably 1 Pa · s to 15 Pa · s. <30> to <37> any one of <30> which is s or less, The manufacturing method of the heat generating body.
<39> coating basis weight of the coating, preferably 150 g / ^{m 2} or more, more preferably 200 g / ^{m 2} or more, more preferably set to 300 g / ^{m 2} or more, and preferably 4600g / ^{m 2} or less, more preferably production process of 3000 g / ^{m 2} or less, more preferably heating element according or less 2200 g / ^{m 2} from <30> to any one of <38>.
<40> The heat generating layer contains the oxidizable metal, the amount of the oxidizable metal, 100 g / ^{m 2} or more 3000 g / ^{m 2} or less, are particularly 200 g / ^{m 2} or more ~1500g / ^{m 2} or less <1> to <39> any one of <39>, The manufacturing method of the heat generating body.
<41> The heating element layer contains a reaction accelerator, and the amount of the reaction accelerator is 4 g / m ² or more and 80 g / m ² or less, particularly 8 g / m ² or more and 50 g / m ² or less. 1> to <40>. A method for producing a heating element according to any one of <40>.
<42> The method for producing a heating element according to any one of <1> to <41>, including a step of spraying an electrolyte after the coating step.
<43> the heating element layer contains an electrolyte, the amount of the electrolyte, 4g / ^{m 2} or more to 40 g / ^{m 2} or less, <42 in particular is 5 g / ^{m 2} or more 30 g / ^{m 2} or less <1> The manufacturing method of the heat generating body of any one of>.
<44> The addition amount of the electrolyte is 0.5 parts or more and 15 parts or less, preferably 0 with respect to 100 parts of the addition amount per unit area of the oxidizable metal particles in the coating process in terms of solid content. The method for producing a heating element according to <42> or <43>, wherein the amount is from 75 parts to 12 parts, more preferably from 1 part to 10 parts.
<45> At least one of the first base sheet and the second base sheet is a method for producing a heating element according to any one of <1> to <44>, wherein the sheet has water absorption.
<46> The method for manufacturing a heating element according to any one of <1> to <44>, wherein at least one of the first base sheet and the second base sheet contains water-absorbing polymer particles.
<47> At least one of the first base sheet and the second base sheet is a sheet having water absorption, and is a fiber sheet containing absorbent polymer particles and a fiber material. <1> to <44> The manufacturing method of the heat generating body of any one of these.
<48> The average particle diameter of the absorbent polymer particles is preferably 1 μm or more, more preferably 10 μm or more, and preferably 1000 μm or less, more preferably 500 μm or less, <46> or <47> Method for producing a heating element.
<49> The proportion of the absorbent polymer particles in each of the first base sheet and the second base sheet is preferably 10% by mass or more, more preferably 20% by mass or more, and preferably The method for producing a heating element according to any one of <46> to <48>, which is 70% by mass or less, more preferably 55% by mass or less.
<50> The basis weight of each of the first base sheet and the second base sheet is preferably 10 g / m ² or more, more preferably 20 g / m ² or more, and preferably 200 g / m ^2. Hereinafter, the method for manufacturing a heating element according to any one of <1> to <49>, more preferably 160 g / m ² or less.
<51> The basis weight of the absorbent polymer contained in each of the first base material sheet and the second base sheet is preferably 5 g / m ² or more, more preferably 10 g / m ² or more. The method for producing a heating element according to any one of <1> to <50>, which is preferably 150 g / m ² or less, more preferably 100 g / m ² or less.
<52> The moisture content of the finally obtained heating element is preferably 5% by mass or more and 40% by mass or less, more preferably 7.5% by mass or more and 30% by mass or less, and further preferably 10% by mass or more and 25% by mass. The method for producing a heating element according to any one of <1> to <51>, wherein:
<53> The moisture content of the entire sheet including the first base sheet, the second base sheet and the heating element layer is preferably 20% by mass or more, more preferably 25% by mass or more, and further preferably 30%. <1> to <52> The method for producing a heating element according to any one of <1> to <52>, wherein the content is at least mass%, and preferably at most 60 mass%, more preferably at most 50 mass%, further preferably at most 40 mass%.

As shown in Table 1, the material of the first base sheet and the second base sheet, the nip pressure in the bonding process, and the presence or absence of the cutting process were changed, and the heating element was manufactured using the manufacturing apparatus of FIG. The following evaluations were made.
・ Falling frequency: Frequency at which delamination occurs during flight conveyor transport ・ Temperature characteristics: Measures the duration for which the temperature exceeds a specified temperature
A: Temperature of 42 ° C or higher is maintained for 6 hours or longer
B: Temperature of 42 ° C. or higher is maintained for 5 to 6 hours
C: Temperature of 42 ° C. or higher is less than 4 hours
B or higher was judged good.
Examples 1 to 3 did not drop off during transportation and had good thermal characteristics. Since all of Comparative Examples 1 were dropped, it was determined to be defective. In Comparative Examples 2 and 3, the thermal characteristics were good, but the defective product rate (dropout frequency) was high and thus judged as defective. In Comparative Example 4, the drop-off frequency was 0%, but it was determined to be defective because the thermal characteristics were less than 4 hours and the duration was too short.
As can be seen, in the manufacturing methods of Examples 1 to 3 in which the cutting process was performed, it was possible to suppress delamination of the heating elements while maintaining the temperature characteristics of the heating elements.

DESCRIPTION OF SYMBOLS 1 1st base material sheet 1A Original fabric roll 1a Uncoated area | region 2 Paint layer 3 Heat generating body layer 4 2nd base material sheet 5, 7 Notch 6 Slit 10 Heat generating body continuous body 11 Heating body 12 1st coating sheet 13 2nd Cover sheet 14 Heating tool continuum 20 Heating element manufacturing apparatus 30 Coating part 31 Die coater 32 Paint 33 Conveyor 40 Electrolyte addition part 41 Electrolyte 50 Bonding part 60 Slit, cutting part 70 First cutting part 71 Cutter blade 72 Rotary Die cutter 73 Anvil roll 80 Re-pitch part 81 Conveyor 90 Discharge part 91 Flight conveyor 92 Roller 93 Endless belt 93a Downward facing part 94 Suction box 100 Covering part 101 Conveyor 110 Sealing part 111 First roll 112 Second roll 200 Cutting blade 201 Disc 202 Slitter blade 203 Clearance 204 Cutting blade

Claims (10)

Coating in which the heating element layer is applied so that an uncoated region is formed on the side edge of the first base sheet on the first base sheet of the long strip conveyed along the longitudinal direction Process,
A laminating step of laminating the first base material sheet and the second base material sheet with the heating element layer interposed therebetween;
Cutting the pasted first base sheet over the direction intersecting the longitudinal direction, and forming a plurality of heating elements of each leaf arranged in a row,
A method of manufacturing a heating element having
The first substrate sheet and the second substrate are formed by forming a plurality of cuts in the uncoated region after the bonding step so that a plurality of cuts are formed in each of the plurality of heating elements of each leaf. The manufacturing method of the heat generating body which has the cutting process process which joins a sheet | seat.   The manufacturing method of the heat generating body of Claim 1 with which the said some notch is distribute | arranged along with the said longitudinal direction of the said 1st base material sheet.   In the incision processing step, the incision blades arranged at equal intervals on the outer periphery of the disk are pressed against the receiving member with the uncoated area where the first base material sheet and the second base material sheet are combined interposed therebetween. Item 3. A method for producing a heating element according to Item 1 or 2.   In the cutting process, by pressing the cutting blade against the receiving member, the portion of the first base sheet in contact with the cutting blade can be pushed into the second base sheet, and the first base The portion of the second base sheet in which the material sheet is pushed in is pushed out to the side opposite to the first base sheet side, and the portion of the first base sheet and the second base material that are pushed out by the cutting blade. The manufacturing method of the heat generating body of Claim 3 with which a sheet | seat is mechanically joined.   After the cutting step, the plurality of heating elements of each leaf are supported on an endless belt with a support surface facing downward in the vertical direction, and the endless belt circulates and the plurality of heating elements of each leaf. The manufacturing method of the heat generating body of any one of Claim 1 to 4 which has the process of conveying.   The said uncoated area | region is a manufacturing method of the heat generating body of any one of Claim 1 to 5 formed in the both-sides edge part of a said 1st base material sheet.   The method for manufacturing a heating element according to any one of claims 1 to 6, wherein the cut has a perforated shape.   The method for manufacturing a heating element according to any one of claims 1 to 7, wherein at least one of the first base sheet and the second base sheet contains a water-absorbing polymer.   The method for manufacturing a heating element according to any one of claims 1 to 7, wherein at least one of the first base sheet and the second base sheet is a sheet having water absorption. 8. The system according to claim 1, wherein at least one of the first base sheet and the second base sheet is a sheet having water absorption, and is a fiber sheet including absorbent polymer particles and a fiber material. The manufacturing method of the heat generating body as described in any one of.

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