Sheet-shaped heater

Abstract

Provided is a sheet-shaped heater having high weld strength. The sheet-shaped heater includes: a part X in which a first bonding auxiliary layer, an electrode, a heat generating layer, and a first insulating layer are laminated in the stated order; and a part Y which is present outside the part X and adjacent to the part X when a main surface is viewed in the perpendicular direction thereof. In the part Y, the heat generating layer and the first insulating layer are laminated in the stated order. In the part X and the part Y, the first bonding auxiliary layer, the heat generating layer, and the first insulating layer are integrated. In the part Y, a first bonding section comprising at least portions of the first bonding auxiliary layer and the heat generating layer is present, and the first bonding auxiliary layer and the heat generating layer are electrically connected by the first bonding section. In the part X, a second bonding section comprising at least portions of the first bonding auxiliary layer and the electrode is present, and the first bonding auxiliary layer and the electrode are electrically connected by the second bonding section.

Description

Sheet-type heater

[0001] This disclosure relates to a sheet-type heater.

[0002] Several sheet-type heaters have been proposed conventionally.

[0003] Patent Document 1 describes a sheet-shaped heater, which includes a portion X in which a first insulating layer, a first adhesive layer, a heating layer, a second adhesive layer, and a second insulating layer are laminated in that order, and a portion Y located inside and adjacent to portion X when the main surface is viewed from the direction perpendicular to it, in which the first insulating layer, the first adhesive layer, a first bonding auxiliary layer, the heating layer, the second adhesive layer, and the second insulating layer are laminated in that order, and a portion Z located inside and adjacent to portion Y when the main surface is viewed from the direction perpendicular to it, in which the first bonding auxiliary layer, the heating layer, the second adhesive layer, and the second insulating layer are laminated in that order, but the first insulating layer and the first adhesive layer are absent, and the A sheet-like heater is described, wherein the first insulating layer in portion X and portion Y is integral, the first bonding auxiliary layer in portion Y and portion Z is integral, the heating layer and the second insulating layer in portion X, portion Y and portion Z are integral, an electrode is present on the main surface of the first bonding auxiliary layer on the side furthest from the heating layer, and the heating layer, the first bonding auxiliary layer and the electrode each have a joint portion comprising at least a part of each, the heating layer, the first bonding auxiliary layer and the electrode are electrically connected by the joint portion, and the first bonding auxiliary layer has a slit in which at least a part of it is present in portion Y and / or portion Z.

[0004] International Publication No. 2024 / 247636

[0005] In sheet-type heaters, high welding strength of the electrodes is preferable. This disclosure provides a sheet-type heater with high welding strength.

[0006] This disclosure relates to a sheet-type heater, comprising a portion X in which a first bonding auxiliary layer, an electrode, a heating layer, and a first insulating layer are laminated in this order, and a portion Y located outside of portion X and adjacent to portion X when the main surface is viewed from the direction perpendicular to it, wherein portion Y comprises the heating layer and the first insulating layer laminated in this order, and does not include the electrode, a part of the first bonding auxiliary layer is in contact with the main surface of the heating layer on the side where the first insulating layer is not present, the first bonding auxiliary layer, the heating layer, and the first insulating layer in portion X and portion Y are integral, and in portion Y, there is a first bonding portion consisting of at least a part of each of the first bonding auxiliary layer and the heating layer, and the first bonding auxiliary layer and the heating layer are electrically connected by the first bonding portion. In the portion X described above, there is a second bonding portion consisting of at least a part of the first bonding auxiliary layer and the electrode, and the first bonding auxiliary layer and the electrode are electrically connected by the second bonding portion, in a sheet-like heater.

[0007] Such a sheet-like heater will also be referred to as the "heater of this disclosure" below.

[0008] According to this disclosure, it is possible to provide a sheet-type heater with high weld strength.

[0009] This is a schematic diagram of the main surface of the heater 1 of the present disclosure corresponding to Embodiment 1, viewed from the direction perpendicular to it. This is a schematic cross-sectional view (diagram) of the line A-A in Figure 1. This is a schematic cross-sectional view (diagram) obtained by cutting the heater of the present disclosure corresponding to Embodiment 2 in the direction perpendicular to its main surface. This is a schematic cross-sectional view (diagram) obtained by cutting the heater of the present disclosure corresponding to Embodiment 3 in the direction perpendicular to its main surface. This is a schematic cross-sectional view (diagram) obtained by cutting the heater of the present disclosure corresponding to Embodiment 4 in the direction perpendicular to its main surface. This is a schematic cross-sectional view (diagram) obtained by cutting the heater of the present disclosure corresponding to Embodiment 4-1 in the direction perpendicular to its main surface. This is a schematic cross-sectional view (diagram) obtained by cutting the heater of the present disclosure corresponding to Embodiment 4-2 in the direction perpendicular to its main surface. This is a schematic cross-sectional view (diagram) obtained by cutting the heater of the present disclosure corresponding to Embodiment 4-3 in the direction perpendicular to its main surface. Figures 9(a) to (g) are schematic diagrams representing the main surfaces of several bonding auxiliary layers. This is a diagram (schematic cross-sectional view) illustrating the manufacturing method of the heater according to the present disclosure, corresponding to Embodiment 4-3. This is another diagram (schematic cross-sectional view) illustrating the manufacturing method of the heater according to the present disclosure, corresponding to Embodiment 4-3. This is yet another diagram (schematic cross-sectional view) illustrating the manufacturing method of the heater according to the present disclosure, corresponding to Embodiment 4-3. This is a photograph showing a tensile testing machine.

[0010] The heaters of this disclosure will be described with reference to the figures. The heaters of this disclosure described below with reference to the figures are all examples, and the heaters of this disclosure are not limited to the embodiments shown in the figures. Also, for the sake of ease of understanding, the figures are schematic, and the scale and other aspects are not limited to those shown.

[0011] <Aspect 1> A first aspect of the heater of the present disclosure (hereinafter also referred to as "Aspect 1") will be described with reference to Figures 1 and 2. Figure 1 is a schematic diagram of the main surface of the heater 1 of the present disclosure corresponding to Aspect 1, viewed from the direction perpendicular to it, and Figure 2 is a cross-sectional view (schematic diagram) of the line A-A in Figure 1.

[0012] The outermost surface of the heater 1 of this disclosure is generally covered by the second insulating layer 9, and the surface of the heat-generating layer 3 is also generally covered by the second insulating layer 9. Only portions X and Y are exposed. In Figure 1, the location where the heat-generating layer 3 exists is shown by a dotted line. This dotted line represents the outer edge of portion Z if the heater 1 of this disclosure has portion Z. In the heater 1 of this disclosure, portion Z is the portion that includes the heat-generating layer 3 at any point in the thickness direction, excluding portions X and Y.

[0013] In the heater 1 of this disclosure, the surface of the electrode 5 is covered by the first bonding auxiliary layer 7 and is not exposed. Therefore, in Figure 1, its outer edge is represented by a dotted line. The area inside this dotted line is part X.

[0014] In Figure 1, a solid line is shown outside of portion X, indicating the outer edge of the first bonding auxiliary layer 7, and further outside of that, a solid line is shown indicating the inner edge of the second insulating layer 9. The second insulating layer 9 exists outside of this solid line, and the area inside this solid line is portion Y, except for the portion that is portion X.

[0015] The heater of this disclosure does not necessarily have a portion Z, and may not have a portion Z in some cases. However, in the embodiments described below with reference to the figures, the cases in which a portion Z exists will be described.

[0016] The heater of this disclosure may have a third insulating layer covering the first junction auxiliary layer 7. However, in the embodiments described below with reference to the figures, embodiments without this third insulating layer will be described. In the embodiments described below with reference to the figures, the illustration of the wiring extending from the electrodes is omitted. By conducting electricity through the wiring, the heating layer generates heat, and the heater of this disclosure performs its role as a heater. In the embodiments described below with reference to the figures, the electrodes are layered. However, the electrodes in the heater of this disclosure do not have to be layered. The electrodes may be, for example, stranded wires (or bundles thereof) extending from the wiring.

[0017] The heater 1 of the present disclosure in the embodiment shown in Figure 1 includes a portion Z when the main surface is viewed from the direction perpendicular to it, a portion Y inside of Z, and a portion X further inside of Y. Here, portion Y is adjacent to portion Z, and portion X is adjacent to portion Y.

[0018] As shown in Figure 2, portion X is the part in which the first bonding auxiliary layer 7, the electrode 5, the heating layer 3, and the first insulating layer 11 are stacked in this order.

[0019] As shown in Figure 2, in portion Y, the heating layer 3 and the first insulating layer 11 are stacked in that order. Portion Y does not contain the electrode 5. In portion Y, a part of the first bonding auxiliary layer 7 is in contact with the main surface of the heating layer 3 on the side where the first insulating layer 11 is not present.

[0020] As shown in Figure 2, section Z is the part in which the second insulating layer 9, the heating layer 3, and the first insulating layer 11 are stacked in this order.

[0021] Here, the first bonding auxiliary layer 7, the heating layer 3, and the first insulating layer 11 in portions X and Y are integrated. Furthermore, it is preferable that the heating layer 3 and the first insulating layer 11 in portions X, Y, and Z are integrated. Also, it is preferable that the first insulating layer 11 in the outer portion of portion Z, portion Z, portion Y, and portion X when the main surface of the heater 1 of this disclosure is viewed from the direction perpendicular to it is integrated. Moreover, it is preferable that the second insulating layer 9 in the outer portion of portion Z and in portion Z when the main surface of the heater 1 of this disclosure is viewed from the direction perpendicular to it is integrated.

[0022] Here, "integrated" means that the parts are not separated and can be recognized as a single object. For example, if a metal fiber sheet is used as the heating layer 3, and the heating layer 3 in parts X, Y, and Z consists of a single metal fiber sheet, then the heating layer 3 in parts X, Y, and Z is considered to be integrated. Also, if an insulating sheet is used as the first insulating layer 11, and the first insulating layer 11 in the outer part of part Z, part Z, part Y, and part X, when the main surface of the heater 1 of this disclosure is viewed from the direction perpendicular to it, consists of a single insulating sheet, then the first insulating layer 11 in the outer part of part Z, part Z, part Y, and part X is considered to be integrated.

[0023] The heater 1 of this disclosure has a first joint portion 13 in a portion Y that electrically connects the first bonding auxiliary layer 7 and the heating layer 3. In Figure 1, four first joint portions 13 are shown, and in Figure 2, two first joint portions 13 are shown, but the number of first joint portions 13 in the heater 1 of this disclosure is not limited and may be one or more, and preferably two or more. The first joint portion 13 consists of at least a part of each of the first bonding auxiliary layer 7 and the heating layer 3. Specifically, it is preferable that the first joint portion 13 is formed when at least a part of each of the first bonding auxiliary layer 15 and the heating layer 3 melts due to heating and then solidifies. In addition to at least a part of each of the first bonding auxiliary layer 7 and the heating layer 3, the first joint portion 13 may also consist of at least a part of another layer.

[0024] The heater 1 of this disclosure has a second joint 15 in a portion X that electrically connects the first bonding auxiliary layer 7 and the electrode 5. Although one second joint 15 is shown in Figures 1 and 2, the number of second joints 15 in the heater 1 of this disclosure is not limited and may be one or more. The second joint 15 consists of at least a portion of each of the first bonding auxiliary layer 7 and the electrode 5. Specifically, it is preferable that the second joint 15 is formed when at least a portion of each of the first bonding auxiliary layer 7 and the electrode 5 melts due to heating and then solidifies. It is preferable that the second joint 15 consists of at least a portion of each of the first bonding auxiliary layer 7 and the electrode 5. Furthermore, the electrode 5 and the heating layer 3 may be in contact, but it is preferable that no bonding by melting and solidification occurs between them.

[0025] The heating method for forming the second joint 15 is not particularly limited, and welding is one example. When the first joining auxiliary layer 7 and the electrode 5 are placed on top of each other and a welding rod is pressed against the surface of the first joining auxiliary layer 7, at least a portion of each of the first joining auxiliary layer 7 and the electrode 5 melts due to the heat. The second joint 15 is then formed by cooling and solidifying.

[0026] The heating method for forming the first joint 13 is not particularly limited, and welding is one example. When the end of the first joining auxiliary layer 7 is brought into contact with the heating layer 3 and a welding rod is pressed against the surface of the first joining auxiliary layer 7, at least a portion of each of the first joining auxiliary layer 7 and the heating layer 3 melts due to the heat. The first joint 13 is then formed by cooling and solidifying the material.

[0027] It is preferable to form the second joint 15 first, and then the first joint 13, because this increases work efficiency.

[0028] <Aspect 2> Next, a second aspect of the heater of the present disclosure (hereinafter also referred to as "Aspect 2") will be described using Figure 3. The heater 1a of the present disclosure corresponding to Aspect 2 is an aspect of the heater 1 of the present disclosure of Aspect 1 in which a second bonding auxiliary layer 21 is added, and otherwise it is the same aspect. When the main surface of the heater 1a of the present disclosure corresponding to Aspect 2 is viewed from the direction perpendicular to it, the second bonding auxiliary layer 21 may appear within the range of part Y in Figure 1, but otherwise it is the same as in Figure 1. Below, the heater 1a of the present disclosure corresponding to Aspect 2 will be described using Figure 3, which is a cross-sectional view (schematic diagram) of Aspect 2 that corresponds to the cross-sectional view (schematic diagram) of line A-A in Aspect 1. In the heater 1a of the present disclosure of Aspect 2 shown in Figure 3, the same elements as the heater 1 of the present disclosure of Aspect 1 are given the same reference numerals.

[0029] The heater 1a of the present disclosure is an embodiment in which the heater 1 of the present disclosure further has a second bonding auxiliary layer 21, and in part X, the first bonding auxiliary layer 7, the electrode 5, the second bonding auxiliary layer 21, the heating layer 3, and the first insulating layer 11 are stacked in this order. In part Y, the second bonding auxiliary layer 21 is in contact with the main surface of the heating layer 3 on the side where the first insulating layer 11 is not present. Therefore, in part Y, the second bonding auxiliary layer 21, the heating layer 3, and the first insulating layer 11 are stacked in this order.

[0030] Furthermore, in the heater 1 of the present disclosure, which is embodiment 1 described above, a portion of the first bonding auxiliary layer 7 was in contact with the main surface of the heating layer 3 on the side where the first insulating layer 11 is not present. However, in the heater 1a of the present disclosure, which is embodiment 2, instead, a portion of the first bonding auxiliary layer 7 is in contact with the main surface of the second bonding auxiliary layer 21 on the side where the heating layer 3 is not present.

[0031] Furthermore, in portion Y, there is a first joint 13a consisting of at least a part of each of the first bonding auxiliary layer 7, the second bonding auxiliary layer 21, and the heating layer 3, and the first bonding auxiliary layer 7, the second bonding auxiliary layer 21, and the heating layer 3 are electrically connected by the first joint 13a. The first joint 13a in embodiment 2 can be formed in the same manner as the first joint 13 in embodiment 1.

[0032] Here, it is preferable that the second bonding auxiliary layer 21 in portions X and Y is integrated.

[0033] <Aspect 3> Next, a third aspect of the heater of the present disclosure (hereinafter also referred to as "Aspect 3") will be described using Figure 4. The heater 1b of the present disclosure corresponding to Aspect 3 is an aspect of the heater 1 of the present disclosure of Aspect 1 in which a third bonding auxiliary layer 23 is added, and otherwise it is the same aspect. When the main surface of the heater 1b of the present disclosure corresponding to Aspect 3 is viewed from the direction perpendicular to it, it is the same as in Figure 1. Below, the heater 1b of the present disclosure corresponding to Aspect 3 will be described using Figure 4, which is a cross-sectional view (schematic diagram) of Aspect 3 that corresponds to the cross-sectional view (schematic diagram) of line A-A in Aspect 1. In the heater 1b of the present disclosure of Aspect 3 shown in Figure 4, the same elements as in the heater 1 of the present disclosure of Aspect 1 are given the same reference numerals.

[0034] The heater 1b of the present disclosure is an embodiment in which the heater 1 of the present disclosure further has a third bonding auxiliary layer 23, and in part X, the first bonding auxiliary layer 7, the electrode 5, the heating layer 3, the third bonding auxiliary layer 23, and the first insulating layer 11 are stacked in this order. In part Y, the third bonding auxiliary layer 23 is in contact with the main surface of the heating layer 3 on the side where the first insulating layer 11 is present. Therefore, in part Y, the heating layer 3, the third bonding auxiliary layer 23, and the first insulating layer 11 are stacked in this order.

[0035] Further, in the portion Y, there is a first bonding portion 13b composed of at least a part of each of the first bonding auxiliary layer 7, the heat generating layer 3, and the third bonding auxiliary layer 23, and the first bonding auxiliary layer 7, the heat generating layer 3, and the third bonding auxiliary layer 23 are electrically connected by the first bonding portion 13b. The first bonding portion 13b in the third aspect can be formed by the same method as the first bonding portion 13 in the first aspect.

[0036] Here, it is preferable that the third bonding auxiliary layer 23 in the portion X and the portion Y is integrated.

[0037] <Aspect 4> Next, a fourth aspect of the heater of the present disclosure (hereinafter also referred to as "Aspect 4") will be described with reference to FIG. 5. The heater 1c of the present disclosure corresponding to Aspect 4 is an aspect obtained by adding the second bonding auxiliary layer 21 and the third bonding auxiliary layer 23 to the heater 1 of the present disclosure according to Aspect 1, and other aspects are the same. When the main surface of the heater 1c of the present disclosure corresponding to Aspect 4 is viewed from the direction of its normal line, the second bonding auxiliary layer 21 may appear within the range of the portion Y in FIG. 1, and other parts are the same as those in FIG. 1. Hereinafter, the heater 1c of the present disclosure corresponding to Aspect 4 will be described with reference to FIG. 5, which is a cross-sectional view (schematic diagram) of Aspect 4 corresponding to the cross-sectional view (schematic diagram) taken along line A-A in Aspect 1. In the heater 1c of the present disclosure of Aspect 4 shown in FIG. 5, the same elements as those of the heater 1 of the present disclosure of Aspect 1 are designated by the same reference numerals.

[0038] The heater 1c of the present disclosure is an aspect in which the heater 1 of the present disclosure further includes the second bonding auxiliary layer 21 and the third bonding auxiliary layer 23. In the portion X, the first bonding auxiliary layer 7, the electrode 5, the second bonding auxiliary layer 21, the heat generating layer 3, the third bonding auxiliary layer 23, and the first insulating layer 11 are laminated in this order. Further, in the portion Y, the second bonding auxiliary layer 21 is in contact with the main surface of the heat generating layer 3 on the side where the first insulating layer 11 does not exist, and the third bonding auxiliary layer 23 is in contact with the main surface of the heat generating layer 3 on the side where the first insulating layer 11 exists. Therefore, in the portion Y, the second bonding auxiliary layer 21, the heat generating layer 3, the third bonding auxiliary layer 23, and the first insulating layer 11 are laminated in this order.

[0039] Furthermore, in the heater 1 of the present disclosure which is the aforementioned aspect 1, a part of the first bonding auxiliary layer 7 is in contact with the main surface of the heat generating layer 3 on the side where the first insulating layer 11 is not provided. Alternatively, in the heater 1c of the present disclosure which is aspect 4, a part of the first bonding auxiliary layer 7 is in contact with the main surface of the second bonding auxiliary layer 21 on the side where the heat generating layer 3 is not provided.

[0040] Further, in the portion Y, there is a first bonding portion 13c formed of at least a part of each of the first bonding auxiliary layer 7, the second bonding auxiliary layer 21, the heat generating layer 3, and the third bonding auxiliary layer 23, and the first bonding portion 13c electrically connects the first bonding auxiliary layer 7, the second bonding auxiliary layer 21, the heat generating layer 3, and the third bonding auxiliary layer 23. The first bonding portion 13c in aspect 4 can be formed by the same method as the first bonding portion 13 in aspect 1.

[0041] Here, it is preferable that the second bonding auxiliary layer 21 in the portion X and the portion Y is integrated, and similarly, it is preferable that the third bonding auxiliary layer 23 is also integrated.

[0042] <Preferred Aspect 1> In the heater of the present disclosure represented by the above aspects 1 to 4, it is preferable that a first adhesive layer is provided between the first insulating layer and the heat generating layer, and the first insulating layer and the heat generating layer are adhered to each other by the first adhesive layer.

[0043] Aspect 4-1 having such a first adhesive layer will be described with reference to FIG. 6. The heater 1c-1 of the present disclosure in aspect 4-1 shown in FIG. 6 is an aspect in which the first adhesive layer 27 is added to the heater 1c of the present disclosure corresponding to aspect 4 described with reference to FIG. 5, and other configurations are the same.

[0044] Hereinafter, the heater 1c-1 of the present disclosure corresponding to aspect 4-1 will be described with reference to FIG. 6, which is a cross-sectional view (schematic diagram) of aspect 4-1 corresponding to the cross-sectional view (schematic diagram) taken along line A-A in aspect 1. In the heater 1c-1 of the present disclosure in aspect 4-1 shown in FIG. 6, the same elements as those of the heater 1 of the present disclosure in aspect 4 are denoted by the same reference numerals.

[0045] In the heater 1c-1 of the present disclosure corresponding to such embodiment 4-1, in portion X, the first bonding auxiliary layer 7, the electrode 5, the second bonding auxiliary layer 21, the heating layer 3, the third bonding auxiliary layer 23, the first adhesive layer 27, and the first insulating layer 11 are laminated in this order.

[0046] In addition, in section Y, the second bonding auxiliary layer 21, the heating layer 3, the third bonding auxiliary layer 23, the first adhesive layer 27, and the first insulating layer 11 are laminated in this order.

[0047] In addition, in section Z, the second insulating layer 9, the heating layer 3, the first adhesive layer 27, and the first insulating layer 11 are laminated in this order.

[0048] In this description, using Figure 6, an embodiment in which a first adhesive layer 27 is added to the heater 1c of the present disclosure corresponding to Embodiment 4 has been explained. However, the heater of the present disclosure may have a first adhesive layer between the first insulating layer and the heating layer in any of Embodiments 1, 2, or 3, and the first insulating layer and the heating layer may be bonded together by the first adhesive layer.

[0049] <Preferred Embodiment 2> In the heaters of the present disclosure represented by embodiments 1 to 4 above, it is preferable that there is a second adhesive layer between the heating layer and the second insulating layer, and that the heating layer and the second insulating layer are attached by the second adhesive layer.

[0050] Embodiment 4-2, which has such a second adhesive layer, will be explained with reference to Figure 7. The heater 1c-2 of the present disclosure in Embodiment 4-2 shown in Figure 7 is an embodiment in which the second adhesive layer 29 is added to the heater 1c of the present disclosure, which corresponds to Embodiment 4 explained with reference to Figure 5, and is otherwise the same embodiment.

[0051] In the following, we will describe the heater 1c-2 of the present disclosure corresponding to Embodiment 4-2, using Figure 7, which is a cross-sectional view (schematic diagram) of Embodiment 4-2 that corresponds to the cross-sectional view (schematic diagram) of line A-A in Embodiment 1. In the heater 1c-2 of the present disclosure of Embodiment 4-2 shown in Figure 7, the same reference numerals are used for the same elements as in the heater 1 of the present disclosure of Embodiment 4.

[0052] In the heater 1c-2 of this disclosure, which corresponds to such embodiment 4-2, in portion X, the first bonding auxiliary layer 7, the electrode 5, the second bonding auxiliary layer 21, the heating layer 3, the third bonding auxiliary layer 23, and the first insulating layer 11 are stacked in this order.

[0053] In addition, in section Y, the second bonding auxiliary layer 21, the heating layer 3, the third bonding auxiliary layer 23, and the first insulating layer 11 are laminated in this order. However, in section Y, the second adhesive layer 29 may be attached to at least a part of the surface of the second bonding auxiliary layer 21.

[0054] In addition, in section Z, the second insulating layer 9, the second adhesive layer 29, the heating layer 3, and the first insulating layer 11 are stacked in this order.

[0055] In this description, using Figure 7, an embodiment in which a second adhesive layer 29 is added to the heater 1c of the present disclosure corresponding to Embodiment 4 has been explained. However, the heater of the present disclosure may have a second adhesive layer 29 between the heating layer 3 and the second insulating layer 9 in any of Embodiments 1, 2, or 3, and the heating layer 3 and the second insulating layer 9 may be bonded together by the second adhesive layer 29.

[0056] <Preferred Embodiment 3> In the heater of the present disclosure, represented by embodiments 1 to 4 above, it is preferable that there is a first adhesive layer between the first insulating layer and the heating layer, with the first insulating layer and the heating layer being bonded by the first adhesive layer, and further, a second adhesive layer between the heating layer and the second insulating layer, with the heating layer and the second insulating layer being bonded by the second adhesive layer.

[0057] Embodiment 4-3, which has such a first adhesive layer and a second adhesive layer, will be described with reference to Figure 8. The heater 1c-3 of the present disclosure in Embodiment 4-3 shown in Figure 8 is an embodiment in which the first adhesive layer 27 and the second adhesive layer 29 are added to the heater 1c of the present disclosure, which corresponds to Embodiment 4 described with reference to Figure 5, and otherwise it is the same embodiment.

[0058] In the following, we will describe the heater 1c-3 of the present disclosure corresponding to Embodiment 4-3, using Figure 8, which is a cross-sectional view (schematic diagram) of Embodiment 4-3 that corresponds to the cross-sectional view (schematic diagram) of line A-A in Embodiment 1. In the heater 1c-3 of the present disclosure of Embodiment 4-3 shown in Figure 8, the same reference numerals are used for the same elements as in the heater 1 of the present disclosure of Embodiment 4.

[0059] In the heater 1c-3 of the present disclosure corresponding to such embodiment 4-3, in portion X, the first bonding auxiliary layer 7, the electrode 5, the second bonding auxiliary layer 21, the heating layer 3, the third bonding auxiliary layer 23, the first adhesive layer 27, and the first insulating layer 11 are laminated in this order.

[0060] In addition, in section Y, the second bonding auxiliary layer 21, the heating layer 3, the third bonding auxiliary layer 23, the first adhesive layer 27, and the first insulating layer 11 are laminated in this order. However, in section Y, the second adhesive layer 29 may be attached to at least a part of the surface of the second bonding auxiliary layer 21.

[0061] In addition, in section Z, the second insulating layer 9, the second adhesive layer 29, the heating layer 3, the first adhesive layer 27, and the first insulating layer 11 are stacked in this order.

[0062] In this description, using Figure 8, an embodiment in which a first adhesive layer 27 and a second adhesive layer 29 are added to the heater 1c of the present disclosure corresponding to Embodiment 4 has been explained. However, the heater of the present disclosure may be an embodiment in which, in Embodiment 1, Embodiment 2, or Embodiment 3, a first adhesive layer is provided between the first insulating layer and the heating layer, and the first insulating layer and the heating layer are bonded by the first adhesive layer, and a second adhesive layer 29 is provided between the heating layer 3 and the second insulating layer 9, and the heating layer 3 and the second insulating layer 9 are bonded by the second adhesive layer 29.

[0063] The heater of this disclosure preferably has the first adhesive layer and / or second adhesive layer as described above, but it does not have to have them. For example, if the first insulating layer and / or second insulating layer is adhesive, the first adhesive layer and / or second adhesive layer may not be present.

[0064] In the heater 1 of this disclosure, it is preferable that the thickness α of the second adhesive layer 29 and the total thickness β of the second bonding auxiliary layer 21 and the heating layer 3 satisfy α < β.

[0065] Here, the thickness of each layer is determined as follows: After obtaining a magnified photograph (200x) of the cross-section of the heater of this disclosure perpendicular to the main surface, as shown in Figure 2, using an optical microscope, the thickness of each layer is measured at 100 randomly selected locations in the magnified photograph, and the simple average value is calculated. The obtained average value is then taken as the thickness of that layer.

[0066] <Slits> In the heaters of the present disclosure represented by embodiments 1 to 4 above, at least one selected from the group consisting of a first bonding auxiliary layer, a second bonding auxiliary layer, and a third bonding auxiliary layer (hereinafter also simply referred to as "bonding auxiliary layer") may have slits. However, as described above, by forming the first joint and / or second joint (hereinafter also simply referred to as "joint"), at least a part of the slit may disappear, or it may become something that cannot be called a slit, such as a hole. Therefore, the concept of a slit in a bonding auxiliary layer includes not only the slit itself, that is, a cut that extends from one main surface of the bonding auxiliary layer to the other main surface, but also something like a hole that was a slit before the formation of the joint but can no longer be called a slit after the formation of the joint, that is, a hole derived from a slit.

[0067] The slits in the bonding auxiliary layer will be explained using Figure 9. Figures 9(a) to (g) are schematic diagrams showing the main surfaces of several bonding auxiliary layers 30. As mentioned above, before forming the joint, the bonding auxiliary layer 30 has slits 301, such as those shown in Figures 9(a) to (g). Each of the bonding auxiliary layers 30 exemplified in Figures 9(a) to (g) has a slit 301. The slit 301 is a cut that extends from one main surface of the bonding auxiliary layer 30 to the other main surface. The method for forming the slit 301 is not particularly limited, but it can be formed using, for example, a utility knife.

[0068] For example, when an electrode 5 or a second bonding auxiliary layer 21 is welded to the surface of the first bonding auxiliary layer 7, the heat may cause deformation of the first bonding auxiliary layer 7 and / or the second bonding auxiliary layer 21. However, if the bonding auxiliary layer in the heater 1 of this disclosure has a slit 301 within portion X and / or portion Y, this deformation is less likely to affect the second insulating layer 9. As a result, the second insulating layer 9 adheres closely to the heating layer 3 over a wide area, and the overall insulating properties of the heater 1 of this disclosure are improved.

[0069] <Details of Each Layer> Next, we will explain the details of each layer.

[0070] <Insulating Layers> The first insulating layer, the second insulating layer, and the third insulating layer will be described below. The first insulating layer, the second insulating layer, and the third insulating layer may be made of the same material and thickness, or they may be different. In the following, when simply referred to as "insulating layer," it means at least one selected from the group consisting of the first insulating layer, the second insulating layer, and the third insulating layer.

[0071] The insulating layer primarily serves to insulate the heating element from the heating element when the heater of this disclosure is installed.

[0072] The insulating layer may be made of materials such as PET (polyethylene terephthalate), PI (polyimide), PP (polypropylene), PE (polyethylene), PEN (polyethylene naphthalate), TAC (triacetylcellulose), silicone resin, or ceramic. These materials have high insulating properties. Among these, an insulating layer made of PI (polyimide) is preferable because it has excellent heat resistance in addition to insulating properties.

[0073] The thickness of the insulating layer is not particularly limited, but is preferably 5 to 100 μm, more preferably 10 to 75 μm, and even more preferably 20 to 55 μm.

[0074] The shape and size of the insulating layer are not particularly limited. However, since the first and second insulating layers serve to electrically insulate the heating layer from the object being heated, the size of their main surfaces is usually the same as or larger than the main surface of the heating layer.

[0075] <Adhesive Layers> The first adhesive layer and the second adhesive layer will be described below. The heater of this disclosure may have the first adhesive layer and / or the second adhesive layer, but may not have them.

[0076] The first adhesive layer and the second adhesive layer may be made of the same material and thickness, or they may be different.

[0077] In the following, when simply referred to as "adhesive layer," it means the first adhesive layer and / or the second adhesive layer.

[0078] The adhesive layer can be formed, for example, by applying an adhesive to the main surface of the insulating layer. Here, examples of adhesives that can be used include acrylic adhesives, silicone adhesives, and rubber elastomers such as NBR. Any type of adhesive can be used, including thermosetting and thermoplastic types.

[0079] Furthermore, an adhesive sheet can be used as the adhesive layer. The adhesive sheet may be a sheet made of the same material as the adhesive described above.

[0080] Multiple adhesive sheets can be layered together to create an adhesive layer.

[0081] The thickness of the first adhesive layer is not particularly limited, but is preferably 25 to 150 μm, more preferably 50 to 100 μm, and even more preferably 65 to 85 μm. If the first adhesive layer consists of multiple adhesive sheets stacked on top of each other, the total thickness of these sheets is considered the thickness of the first adhesive layer.

[0082] The thickness of the second adhesive layer is not particularly limited, but is preferably 5 to 120 μm, more preferably 10 to 75 μm, and even more preferably 15 to 40 μm. If the second adhesive layer consists of multiple adhesive sheets stacked on top of each other, the total thickness of these sheets is considered the thickness of the second adhesive layer.

[0083] <Heating Layer> The heating layer will now be explained. The heating layer can be any sheet-like material that generates heat when electricity is passed through it. The material of the heating layer is preferably stainless steel (e.g., SUS304, SUS316, SUS316L), but it may also be Cu (copper), Al (aluminum), Ni (nickel), nichrome, or carbon.

[0084] The heating layer is preferably made of a fibrous material. For example, it may be a metal mesh in which linear fibers are arranged substantially perpendicularly in a sheet, a metal fiber nonwoven fabric in which metal fibers are arranged randomly, a metal fiber woven fabric, linear metal fibers, or tape-shaped metal fibers.

[0085] Here, examples of metal meshes include those with a mesh count of 200 to 500. Examples of metal fiber nonwoven fabrics include those with a mesh count of 1500 g / m². 2 Examples include stainless steel fiber nonwoven fabric (SUS316L needle punch web, manufactured by Nikko Techno Co., Ltd.). Examples of metal fiber woven fabrics include SUS cloth (Naslon cloth A, manufactured by Nippon Seisen Co., Ltd.). Examples of linear metal fibers include filament yarn (Naslon 12-2000 / 3, manufactured by Nippon Seisen Co., Ltd.). Examples of tape-shaped metal fibers include SUS tape (Naslon tape B W16 (manufactured by Nippon Seisen Co., Ltd.)).

[0086] The thickness of the heating layer is preferably 10 to 600 μm, more preferably 20 to 150 μm, and even more preferably 25 to 50 μm. By using a heating layer of such thickness, the flexibility of the heater of this disclosure can be ensured, while also ensuring the bonding strength between the heating layer, the second bonding auxiliary layer, and the third bonding auxiliary layer.

[0087] The shape and size of the heating element can be adjusted as appropriate to suit the shape and size of the object being heated.

[0088] The heating layer preferably has an electrical resistivity of 5 to 3000 μΩcm, and more preferably 10 to 2500 μΩcm. Here, the electrical resistivity of the heating layer shall be the value determined in accordance with JIS K 7194.

[0089] The heating layer is preferably composed mainly of metal fibers, and more preferably composed solely of metal fibers. Here, "mainly" means 70% by mass or more. That is, it is preferable that 70% by mass or more of the heating layer is metal fibers. The proportion of metal fibers in the heating layer is more preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 95% by mass or more. Furthermore, "composed solely of metal fibers" means that 98% by mass or more is metal fiber. By setting the proportion of metal fibers in the heating layer as described above, the conductivity and heating properties of the heating layer can be fully exhibited.

[0090] The proportion of metal fibers contained in the heating layer shall be determined by the following method: The surface of the heating layer shall be magnified 1,000 times using an EDS-equipped scanning electron microscope (SEM-EDS), and the type of metal fiber shall be identified by EDS elemental analysis. Then, the area of ​​metal fibers (excluding voids) within a 90 μm × 120 μm field of view shall be measured from the SEM image using an image processing device. This area shall be converted to a volume ratio by raising it to the power of 3 / 2, and the mass ratio shall be calculated by multiplying it by the true specific gravity of the metal fibers to determine the metal fiber content. If two or more types of metal fibers are present, the content of each metal fiber shall be calculated and the sum of these values ​​shall be considered the proportion of metal fibers contained in the heating layer.

[0091] The metal fiber is preferably a metallic fiber with an equivalent diameter of an equiarea circle in its cross-section of 2 to 100 μm (preferably 5 to 20 μm) and a length of 2 to 20 mm. Furthermore, in the SEM image obtained by magnifying the metal fiber 1000 times using a scanning electron microscope (SEM), 30 locations are arbitrarily selected from the image to determine the cross-sectional area of ​​the metal fiber at each location. After calculating the simple average of these cross-sectional areas, the equivalent diameter of an equiarea circle in the cross-section of the metal fiber is calculated using the obtained average cross-sectional area.

[0092] Furthermore, the heating layer is preferably a metal fiber nonwoven fabric (hereinafter also referred to as a metal fiber sheet) in which such metal fibers are randomly arranged. Here, the metal fiber sheet consists only of metal fibers and may have voids, but in addition to metal fibers, it may also contain other materials (for example, resin fibers that function as a binder) to the extent that they do not hinder the heating properties. Examples of binders include carbon, glass, and silicone resin.

[0093] Here, it is preferable that the metal fibers constituting the metal fiber sheet are connected at contact points to the extent that they can conduct electricity. For example, it is more preferable that some of the metal fibers melt by sintering at a high temperature, and then solidify, causing the metal fibers to fuse together at their contact points.

[0094] Because the metal fiber sheet has high heat resistance and chemical resistance, a stainless steel fiber sheet is preferable. Examples of stainless steel fiber sheets include stainless steel fiber sheets (for example, Tommy Firec SS, manufactured by Tomoegawa Paper Co., Ltd.).

[0095] The metal fiber sheet has a basis weight of 25 g / m². 2 Preferably, it is 50 g / m 2 It is preferable that the amount is greater than or equal to 1000 g / m². 2 Preferably, it is 200 g / m². 2 The following is more preferable. When the basis weight of the metal fiber sheet is such a value, the strength of the metal fiber sheet can be ensured, and the contact points between the metal fibers can be made relatively uniform. Therefore, the flexibility of the heater of this disclosure can be ensured, and the bonding strength between the heating layer, the second bonding auxiliary layer and the third bonding auxiliary layer can also be ensured. The basis weight is calculated by determining the volume of fibers per unit area of ​​the metal fiber sheet from image observation with an optical microscope, and then determining the weight from the specific gravity.

[0096] The density of the metal fiber sheet is 1.0 to 5.0 g / cm³. 3 Preferably, it is 1.4 to 2.0 g / cm³. 3 It is more preferable that the concentration be 1.7 g / cm³. 3It is preferable that the density falls within this range. The density of the metal fiber sheet is determined in accordance with JIS P 8118, where the density (g / cm 3 ) = basis weight (g / m 2 ) / (thickness (mm) × 1000). When the density of the metal fiber sheet is within this range, the strength of the metal fiber sheet can be ensured, and the contact points between metal fibers can be made relatively uniform, so the bonding strength between the heat-generating layer, the second bonding auxiliary layer and the third bonding auxiliary layer can also be ensured.

[0097] The metal fiber sheet can be produced either by a dry nonwoven fabric production method or by a wet papermaking method. When produced by the wet papermaking method, for example, countless metal fibers having an equivalent circle diameter of cross-section of 2 to 100 µm and a length of 2 to 20 mm are stirred in a dispersion medium (such as water or an organic solvent), then an organic flocculant or the like is added, the mixture is formed into a sheet using a square hand-sheet former (manufactured by Toyo Seiki Co., Ltd., etc.), and a dry sheet having a basis weight of 50 to 1100 g / m 2 is obtained. Thereafter, firing at 400 to 1300°C yields the metal fiber sheet.

[0098] <Bonding Auxiliary Layer> The first bonding auxiliary layer, the second bonding auxiliary layer and the third bonding auxiliary layer will be described. The first bonding auxiliary layer, the second bonding auxiliary layer and the third bonding auxiliary layer may be the same in material, size, thickness and the like, or may be different from one another.

[0099] In the following description, when simply referred to as "bonding auxiliary layer", it means at least one selected from the group consisting of the first bonding auxiliary layer, the second bonding auxiliary layer and the third bonding auxiliary layer.

[0100] When the second bonding auxiliary layer and / or the third bonding auxiliary layer are used in addition to the first bonding auxiliary layer, they are preferably made of the same material. This is because in this case, stronger first bonding parts and / or second bonding parts are easily formed.

[0101] The bonding auxiliary layer is not particularly limited in material, as long as it is conductive. It may be made of Cu (copper), Al (aluminum), Ni (nickel), nichrome, carbon, Fe (iron), Cr (chromium), etc., but stainless steel is particularly preferred. The material can be appropriately selected considering the bonding strength with the electrode and heating layer, ease of bonding, flexibility, etc.

[0102] The bonding auxiliary layer may be, for example, a metal foil, a sheet-like metal mesh, a metal fiber nonwoven fabric, a metal fiber woven fabric, a linear metal fiber, or a tape-like metal fiber.

[0103] Here, examples of metal meshes include those with a mesh count of 200 to 500. Examples of metal fiber nonwoven fabrics include those with a mesh count of 1500 g / m². 2 Examples include stainless steel fiber nonwoven fabric (SUS316L needle punch web, manufactured by Nikko Techno Co., Ltd.). Examples of metal fiber woven fabrics include SUS cloth (Naslon cloth A, manufactured by Nippon Seisen Co., Ltd.). Examples of linear metal fibers include filament yarn (Naslon 12-2000 / 3, manufactured by Nippon Seisen Co., Ltd.). Examples of tape-shaped metal fibers include SUS tape (Naslon tape B W16 (manufactured by Nippon Seisen Co., Ltd.)).

[0104] The bonding auxiliary layer is preferably a metal foil, and more preferably a stainless steel foil. A metal foil facilitates welding and bonding with the electrodes.

[0105] When the electrode material is stainless steel, using a first bonding auxiliary layer also made of stainless steel facilitates the formation of a second bonding layer. This effect is enhanced when both layers are made of stainless steel of the same composition.

[0106] Using stainless steel foil as a bonding auxiliary layer provides the simultaneous advantages of facilitating welding and facilitating the formation of the first and / or second joints. In this case, even if the first and / or second joints are small, the joint strength of these joints can be ensured while maintaining the flexibility of the heater according to this disclosure.

[0107] For example, if the electrodes are made of copper or stainless steel, the bonding auxiliary layer may also be made of copper or stainless steel.

[0108] The shape and size of the bonding auxiliary layer can be adjusted as appropriate, but it is preferable that the area of ​​the main surface facing the electrode in each layer is larger than the area of ​​the main surface facing the bonding auxiliary layer on the electrode.

[0109] The bonding auxiliary layer preferably has an electrical resistivity of 5 to 100 μΩcm, and more preferably 10 to 90 μΩcm. Here, the electrical resistivity of the bonding auxiliary layer shall be the value determined in accordance with JIS K 7194.

[0110] The thickness of the bonding auxiliary layer is preferably 1 to 60 μm, more preferably 3 to 35 μm, and even more preferably 5 to 15 μm. With such thicknesses, the flexibility of the heater of this disclosure can be ensured while also ensuring the bonding strength between the bonding auxiliary layer and the electrode.

[0111] <Electrodes> The electrodes will be described below. The electrodes should be capable of connecting to an external power source and supplying electricity from the external power source to the heating layer.

[0112] The electrode material is not particularly limited. It may be Cu (copper), Ag (silver), Au (gold), etc., but stainless steel (e.g., SUS304, SUS316, SUS316L) is particularly preferred.

[0113] The electrode structure may be, for example, a metal foil, a metal mesh in which linear fibers are arranged substantially perpendicularly in a sheet-like shape, a metal fiber nonwoven fabric in which metal fibers are arranged randomly, a metal fiber woven fabric, linear metal fibers, or tape-shaped metal fibers.

[0114] Here, examples of metal meshes include those with a mesh count of 200 to 500. Examples of metal fiber nonwoven fabrics include those with a mesh count of 1500 g / m². 2Examples include stainless steel fiber nonwoven fabric (SUS316L needle punch web, manufactured by Nikko Techno Co., Ltd.). Examples of metal fiber woven fabrics include SUS cloth (Naslon cloth A, manufactured by Nippon Seisen Co., Ltd.). Examples of linear metal fibers include filament yarn (Naslon 12-2000 / 3, manufactured by Nippon Seisen Co., Ltd.). Examples of tape-shaped metal fibers include SUS tape (Naslon tape B W16 (manufactured by Nippon Seisen Co., Ltd.)).

[0115] The electrodes are equipped with a connection point for an external power supply, and are configured to allow power to be supplied to the heating layer from the external power supply. For example, the external power supply and the electrodes may be connected by a cable using crimp terminals or the like.

[0116] The shape and size of the electrodes can be adjusted as needed, as long as they allow for connection to an external power supply and sufficient current to flow to the heating layer.

[0117] The electrodes preferably have a specific electrical resistivity of 5 to 100 μΩcm, and more preferably 10 to 90 μΩcm. Here, the specific electrical resistivity of the electrodes is determined by XRD analysis of the electrodes to find their constituent composition, and then calculated using the formula "specific electrical resistivity = 1 / electrical conductivity," with reference to the electrical conductivity determined from the elemental composition.

[0118] The electrodes are preferably made of fibrous material, and more preferably a woven fabric made of twisted metal fibers, or a woven metal fiber fabric. If the electrodes are made of twisted metal fibers, or a woven metal fiber fabric, they have appropriate flexibility and strength, so even if an external force is applied to the heater, the joint between the heating layer and the electrodes is less likely to come apart.

[0119] Furthermore, the woven fabric made of twisted metal fibers and the metal fiber woven fabric may use fibers other than metal fibers as constituent elements, but it is preferable that they consist mainly of metal fibers, and more preferably that they consist only of metal fibers. Here, "mainly" means 70% by mass or more. That is, it is preferable that the electrode consists of 70% by mass or more metal fibers, more preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 95% by mass or more. "Composed only of metal fibers" means that 98% by mass or more are metal fibers. The woven fabric made of twisted metal fibers and the metal fiber woven fabric may have voids, but they may also contain other materials (for example, resin fibers that function as a binder).

[0120] The woven fabric made of twisted metal fibers and the metal fibers constituting the woven fabric are preferably fibers with an equivalent diameter of an equiarea circle in cross-section of 1 to 50 μm (preferably 2 to 30 μm). In this case, the electrode is viewed using a scanning electron microscope (SEM) at 1000x magnification, and 30 locations are arbitrarily selected from the image to view the cross-section of the metal fibers. The area of ​​the cross-section of the metal fibers at each location is determined, and the simple average value is calculated. The equivalent diameter of an equiarea circle in the cross-section of the metal fibers is then calculated using the obtained average cross-sectional area. By having the equivalent diameter of an equiarea circle in the cross-section of the metal fibers within this range, the flexibility of the heater of this disclosure can be ensured, while also ensuring the bonding strength between the first bonding auxiliary layer and the electrode.

[0121] The electrode thickness is preferably 0.5 to 3 mm. This thickness ensures the flexibility of the heater according to this disclosure while also making it easier to ensure the bonding strength between the first bonding auxiliary layer and the electrode.

[0122] The heater of this disclosure may include other layers or sheet-like substrates that do not correspond to the first insulating layer, second insulating layer, third insulating layer, electrodes, heating layer, first adhesive layer, second adhesive layer, first bonding auxiliary layer, second bonding auxiliary layer, and third bonding auxiliary layer as described above. For example, the first insulating layer may have a sheet-like substrate on the main surface on the side where the heating layer is not present, via an adhesive layer.

[0123] The sheet-like substrate is preferably made of a material that has insulating and flexible properties, such as PET (polyethylene terephthalate), PI (polyimide), PP (polypropylene), PE (polyethylene), PEN (polyethylene naphthalate), or TAC (triacetylcellulose). The sheet-like substrate may also be made of a fluororesin. Examples of fluororesins include polytetrafluoroethylene (PTFE), vinylidene fluoride-hexafluoropropylene copolymer, and vinylidene fluoride-tetrafluoroethylene-hexafluoropropylene copolymer. Furthermore, the sheet-like substrate may be a high-strength, high-insulating sheet made by impregnating glass, aramid (aromatic polyamide resin), carbon fiber, or other reinforcing fibers with a fluororesin.

[0124] The thickness of the sheet-like substrate is not particularly limited, but is preferably 15 to 100 μm, more preferably 30 to 75 μm, and even more preferably about 50 μm.

[0125] <Manufacturing Method> The manufacturing method of the heater of this disclosure will be explained with reference to Figures 10 to 12. Figures 10 to 12 are cross-sectional views obtained when the heater of this disclosure is cut in a direction parallel to the perpendicular to its main surface, similar to Figure 2. The manufacturing method of the heater 1 of this disclosure is not particularly limited, but it is preferable to manufacture it by the method described below. Below, the method for manufacturing the heater 1c-3 of this disclosure in embodiment 4-3 shown in Figure 8 will be described, but other embodiments of the heater of this disclosure can be manufactured in the same manner.

[0126] First, the first insulating layer 11, the first adhesive layer 27, the third bonding auxiliary layer 23, the heating layer 3, the second bonding auxiliary layer 21, the second adhesive layer 29, and the second insulating layer 9 are laminated in this order to create a sheet 40 in the configuration shown in Figure 10. The first adhesive layer 27 can be formed by applying adhesive to the surface of the first insulating layer 11. The second adhesive layer 29 can be formed by applying adhesive to the surface of the second insulating layer 9.

[0127] Next, using a utility knife or the like, a portion of the second insulating layer 9 and the second adhesive layer 29 are cut away so that a portion of the surface of the second bonding auxiliary layer 21 on the sheet 40 is exposed, thereby obtaining a sheet 42 in the configuration shown in Figure 11.

[0128] Next, the electrode 5 is placed on a base material made of a metal plate, the first bonding auxiliary layer 7 is placed on top of the electrode 5, and a welding pen is pressed against the first bonding auxiliary layer 7 to perform spot welding. As a result, at least a portion of both the first bonding auxiliary layer 7 and the electrode 5 melts simultaneously. Then, they solidify, forming the second joint 15. With the formation of the second joint 15, the first bonding auxiliary layer 7 and the electrode 5 are physically joined and electrically connected.

[0129] Next, the joined first bonding auxiliary layer 7 and electrode 5 are positioned as shown in Figure 12, with the electrode 5 in contact with the surface of the second bonding auxiliary layer 21. Then, a welding pen is pressed against one or more locations on the outer periphery of the surface of the first bonding auxiliary layer 7 to perform spot welding. As a result, at least a portion of each of the first bonding auxiliary layer 7, the second bonding auxiliary layer 21, the heating layer 3, and the third bonding auxiliary layer 23 melts simultaneously. After that, they solidify to form the first joint 13c. Thus, the heater 1c-3 of the present disclosure in the embodiment shown in Figure 8 can be obtained.

[0130] The heater of this disclosure can be manufactured easily as described above; in other words, it is highly productive.

[0131] <How to use> In the heater of this disclosure, electricity supplied from an external power source passes from the electrode 5 through the first bonding auxiliary layer 7 and the first bonding portion 13c to reach the heating layer 3. The heating layer 3 then generates heat and heats the object to be heated.

[0132] The object to be heated is not particularly limited and may be, for example, a pipe. Because the surface of a pipe is curved, when a sheet-type heater is attached to it, the adhesion of the insulating layer to the heating layer tends to decrease in general. In contrast, with the sheet-type heater of the present invention, even if the object to be heated is a pipe, the insulating layer adheres to the heating layer over a wide area via the adhesive layer.

[0133] The heaters of this disclosure preferably have a weld strength of 20 to 50 N, and more preferably 30 to 50 N, as measured by tensile testing. When the weld strength is within the above range, the sheet-like heater is less likely to break even if stress is applied to the welded area. The method for measuring the weld strength will be explained later when giving examples.

[0134] The present invention includes the following embodiments (1) to (10). (1) A sheet-shaped heater comprising a portion X in which a first bonding auxiliary layer, an electrode, a heating layer, and a first insulating layer are laminated in this order, and a portion Y which is located outside the portion X and adjacent to the portion X when the main surface is viewed from the direction perpendicular to it, wherein the portion Y comprises the heating layer and the first insulating layer laminated in this order, and does not include the electrode, a part of the first bonding auxiliary layer is in contact with the main surface of the heating layer on the side where the first insulating layer is not present, the first bonding auxiliary layer, the heating layer, and the first insulating layer in the portion X and the portion Y are integral, and in the portion Y, there is a first bonding portion consisting of at least a part of the first bonding auxiliary layer and the heating layer, and the first bonding auxiliary layer and the heating layer are electrically connected by the first bonding portion. A sheet-shaped heater in which, in the portion X, there is a second bonding portion consisting of at least a part of the first bonding auxiliary layer and the electrode, and the first bonding auxiliary layer and the electrode are electrically connected by the second bonding portion. (2) The sheet-like heater according to (1) above, further comprising a second bonding auxiliary layer, wherein in portion X, the first bonding auxiliary layer, the electrode, the second bonding auxiliary layer, the heating layer, and the first insulating layer are stacked in this order, in portion Y, the second bonding auxiliary layer is in contact with the main surface of the heating layer on the side where the first insulating layer is not present, and instead of the main surface of the heating layer on the side where the first insulating layer is not present, a part of the first bonding auxiliary layer is in contact with the main surface of the second bonding auxiliary layer on the side where the heating layer is not present, and in portion Y, there is a first bonding portion consisting of at least a part of each of the first bonding auxiliary layer, the second bonding auxiliary layer, and the heating layer, and the first bonding auxiliary layer, the second bonding auxiliary layer, and the heating layer are electrically connected by the first bonding portion.(3) The sheet heater according to (1) above, further comprising a third bonding auxiliary layer, wherein in portion X, the first bonding auxiliary layer, the electrode, the heating layer, the third bonding auxiliary layer, and the first insulating layer are stacked in this order, in portion Y, the third bonding auxiliary layer is in contact with the main surface of the heating layer on the side where the first insulating layer is present, and in portion Y, there is a first bonding portion consisting of at least a part of each of the first bonding auxiliary layer, the heating layer, and the third bonding auxiliary layer, and the first bonding auxiliary layer, the heating layer, and the third bonding auxiliary layer are electrically connected by the first bonding portion. (4) The sheet heater according to (1) above, further comprising a second bonding auxiliary layer and a third bonding auxiliary layer, wherein in portion X, the first bonding auxiliary layer, the electrode, the second bonding auxiliary layer, the heating layer, the third bonding auxiliary layer, and the first insulating layer are stacked in this order, in portion Y, the second bonding auxiliary layer is in contact with the main surface of the heating layer on the side where the first insulating layer is not present, a part of the first bonding auxiliary layer is in contact with the main surface of the second bonding auxiliary layer on the side where the heating layer is not present instead of the main surface of the heating layer on the side where the first insulating layer is not present, and the third bonding auxiliary layer is in contact with the main surface of the heating layer on the side where the first insulating layer is present, and in portion Y, there is a first bonding portion consisting of at least a part of each of the first bonding auxiliary layer, the second bonding auxiliary layer, the heating layer, and the third bonding auxiliary layer, and the first bonding auxiliary layer, the second bonding auxiliary layer, the heating layer, and the third bonding auxiliary layer are electrically connected by the first bonding portion. (5) A sheet-like heater according to any one of (1) to (4) above, which, when the main surface is viewed from the direction perpendicular to it, is located outside of and adjacent to portion Y, and includes portion Z in which a second insulating layer, the heating layer, and the first insulating layer are laminated in this order, and the heating layer and the first insulating layer in portion X, portion Y, and portion Z are integral.(6) A sheet-type heater according to any one of (1) to (5) above, wherein a first adhesive layer is provided between the first insulating layer and the heating layer, and the first insulating layer and the heating layer are bonded by the first adhesive layer. (7) A sheet-type heater according to (5) or (6) above, wherein a second adhesive layer is provided between the heating layer and the second insulating layer, and the heating layer and the second insulating layer are bonded by the second adhesive layer. (8) A sheet-type heater according to any one of (1) to (7) above, wherein the electrodes are layered. (9) A sheet-type heater according to any one of (1) to (8) above, wherein the welding strength measured by a tensile test is 20 to 50 N. (10) A sheet-type heater according to any one of (1) to (9) above, wherein in at least a part of the portion Y and in the portion X, a third insulating layer is provided on the side of the first bonding auxiliary layer where the first insulating layer is absent.

[0135] A sheet-like heater with the cross-section shown in Figure 8 was fabricated. This will be referred to as Sample 1 below.

[0136] (Materials used in Sample 1) The following materials were used for each layer of Sample 1: ・First insulating layer and second insulating layer: Polyimide coating (Kapton EN, manufactured by Toray DuPont), 25 μm thick ・Second adhesive layer: Layer made of fluorine-based adhesive, three layers of 25 μm thickness stacked together (total 75 μm) ・First adhesive layer: Layer made of fluorine-based adhesive, 25 μm thick ・Heating layer: Stainless steel paper (Tommy Firec SS, manufactured by Tomoegawa Paper Co., Ltd.), 30 μm thick ・First bonding auxiliary layer, second bonding auxiliary layer and third bonding auxiliary layer: Stainless steel foil (SUS-316L), 10 μm thick, with slits as shown in Figure 9(e).

[0137] (Sample 1 Manufacturing Method) A first adhesive layer was applied to the surface of the first insulating layer, and a second adhesive layer was applied to the surface of the second insulating layer. Next, the third bonding auxiliary layer, the heating layer, and the second bonding auxiliary layer were laminated in this order. Then, with the surface of the third bonding auxiliary layer facing the surface of the first adhesive layer of the first insulating layer with the first adhesive layer attached, and the surface of the second bonding auxiliary layer facing the surface of the second adhesive layer of the second insulating layer with the second adhesive layer attached, a thermal lamination treatment was performed to obtain a sheet A in the form shown in Figure 10. Next, using a cutter knife, a portion of the second insulating layer and the second adhesive layer was cut out so that a portion of the surface of the second bonding auxiliary layer on sheet A was exposed, and a sheet B in the form shown in Figure 11 was obtained. Next, an electrode was placed on a base material made of a metal plate, the first bonding auxiliary layer was placed on top of the electrode, and a welding pen was pressed on top of the first bonding auxiliary layer to perform spot welding, simultaneously melting and solidifying a portion of the first bonding auxiliary layer and the electrode, and a member A consisting of the first bonding auxiliary layer and the electrode was obtained in the form shown in Figure 12, with the second joint 15 formed. Next, as shown in Figure 12, member A was positioned so that the electrodes of member A were in contact with the surface of the second bonding auxiliary layer. Then, a welding pen was pressed against two locations on the outer periphery of the surface of the first bonding auxiliary layer of member A (locations without electrodes at the bottom) to perform spot welding, simultaneously melting and solidifying parts of the first bonding auxiliary layer, the second bonding auxiliary layer, the heating layer, and the third bonding auxiliary layer, thereby obtaining sample 1, a heater in the manner shown in Figure 8, in which the first joint portion 13c in the manner shown in Figure 8 was formed.

[0138] Furthermore, a comparative sheet-type heater was created for comparison. This will be referred to as Sample 2 below.

[0139] (Materials used in Sample 2) Each layer of Sample 2 used the same materials as in Sample 1.

[0140] (Sample 2 Manufacturing Method) After obtaining sheet B in the same manner as in Sample 1, spot welding was performed by pressing a welding pen onto the second bonding auxiliary layer of sheet B, simultaneously melting and solidifying a portion of each of the second bonding auxiliary layer, the heating layer, and the third bonding auxiliary layer, thereby obtaining sheet C in which a third joint was formed. Next, member B consisting of the first bonding auxiliary layer and electrodes used in member A was laminated. Next, member B was positioned so that the electrodes of member B were in contact with the surface of the second bonding auxiliary layer having the third joint, and then a welding pen was pressed onto two locations on the outer periphery of the surface of the first bonding auxiliary layer of member B (locations without electrodes at the bottom), thereby performing spot welding, simultaneously melting and solidifying a portion of each of the first bonding auxiliary layer, the second bonding auxiliary layer, the heating layer, and the third bonding auxiliary layer, thereby obtaining sample 2, a comparative heater in which a first joint 13c in the manner shown in Figure 8 was formed.

[0141] Tensile tests were performed on each of these two samples. First, each sample was attached to a SUS plate using double-sided adhesive tape. Here, the main surface of the first insulating layer of the sample was attached so that it was in close contact with the main surface of the SUS plate. Next, as shown in Figure 13, the sample attached to the SUS plate was clamped and fixed in the thickness direction in a Tensilon tensile testing machine, and a tensile test was performed by pulling a 70 mm wiring extending from the electrode at 50 mm / min. By pulling in this way, a load was applied to the joint. The peak strength (N) at which the joint broke was then measured. This test was performed five times for each sample, and the average value was calculated. This value (average value) was defined as the weld strength. The evaluation results are shown in Table 1 below.

[0142]

[0143] As a result, in the case of Sample 1, which corresponds to the heater of this disclosure, the weld strength was 34.4 N. In contrast, the weld strength of the comparison sheet-type heater was 10.4 N. Through this experiment, it was confirmed that the heater of this disclosure has high weld strength.

[0144] This application claims priority based on Japanese Patent Application No. 2025-48656, filed on 24 March 2025, and incorporates all of its disclosures herein.

[0145] 1, 1a, 1b, 1c, 1c-1, 1c-2, 1c-3 Heater of the present disclosure 3 Heating layer 5 Electrode 7 First bonding auxiliary layer 9 Second insulating layer 11 First insulating layer 13, 13a, 13b, 13c First joint 15 Second joint 21 Second bonding auxiliary layer 23 Third bonding auxiliary layer 27 First adhesive layer 29 Second adhesive layer 30 Bonding auxiliary layer 301 Slit 40, 42 Sheet

Claims

1. A sheet-shaped heater, comprising a portion X in which a first bonding auxiliary layer, an electrode, a heating layer, and a first insulating layer are laminated in this order, and a portion Y located outside of portion X and adjacent to portion X when the main surface is viewed from the direction perpendicular to it, wherein portion Y comprises the heating layer and the first insulating layer laminated in this order, and does not include the electrode, a part of the first bonding auxiliary layer is in contact with the main surface of the heating layer on the side where the first insulating layer is not present, the first bonding auxiliary layer, the heating layer, and the first insulating layer in portion X and portion Y are integral, and in portion Y, there is a first bonding portion consisting of at least a part of the first bonding auxiliary layer and the heating layer, and the first bonding auxiliary layer and the heating layer are electrically connected by the first bonding portion. A sheet-shaped heater in which, in the portion X, there is a second bonding portion consisting of at least a part of the first bonding auxiliary layer and the electrode, and the first bonding auxiliary layer and the electrode are electrically connected by the second bonding portion.

2. The sheet heater according to claim 1, further comprising a second bonding auxiliary layer, wherein in portion X, the first bonding auxiliary layer, the electrode, the second bonding auxiliary layer, the heating layer, and the first insulating layer are stacked in this order, in portion Y, the second bonding auxiliary layer is in contact with the main surface of the heating layer on the side where the first insulating layer is not present, and instead of the main surface of the heating layer on the side where the first insulating layer is not present, a part of the first bonding auxiliary layer is in contact with the main surface of the second bonding auxiliary layer on the side where the heating layer is not present, and in portion Y, there is a first bonding portion consisting of at least a part of each of the first bonding auxiliary layer, the second bonding auxiliary layer, and the heating layer, and the first bonding auxiliary layer, the second bonding auxiliary layer, and the heating layer are electrically connected by the first bonding portion.

3. The sheet-like heater according to claim 1, further comprising a third bonding auxiliary layer, wherein in portion X, the first bonding auxiliary layer, the electrode, the heating layer, the third bonding auxiliary layer, and the first insulating layer are stacked in this order, in portion Y, the third bonding auxiliary layer is in contact with the main surface of the heating layer on the side where the first insulating layer is present, and in portion Y, there exists a first bonding portion consisting of at least a part of each of the first bonding auxiliary layer, the heating layer, and the third bonding auxiliary layer, and the first bonding auxiliary layer, the heating layer, and the third bonding auxiliary layer are electrically connected by the first bonding portion.

4. The sheet heater according to claim 1, further comprising a second bonding auxiliary layer and a third bonding auxiliary layer, wherein in portion X, the first bonding auxiliary layer, the electrode, the second bonding auxiliary layer, the heating layer, the third bonding auxiliary layer, and the first insulating layer are laminated in this order, in portion Y, the second bonding auxiliary layer is in contact with the main surface of the heating layer on the side where the first insulating layer is not present, a part of the first bonding auxiliary layer is in contact with the main surface of the second bonding auxiliary layer on the side where the heating layer is not present instead of the main surface of the heating layer on the side where the first insulating layer is not present, and the third bonding auxiliary layer is in contact with the main surface of the heating layer on the side where the first insulating layer is present, and in portion Y, there is a first bonding portion consisting of at least a part of each of the first bonding auxiliary layer, the second bonding auxiliary layer, the heating layer, and the third bonding auxiliary layer, and the first bonding auxiliary layer, the second bonding auxiliary layer, the heating layer, and the third bonding auxiliary layer are electrically connected by the first bonding portion.

5. A sheet-like heater according to any one of claims 1 to 4, wherein, when the main surface is viewed from the direction perpendicular to it, a portion Z exists outside of portion Y and adjacent to portion Y, and the second insulating layer, the heating layer, and the first insulating layer are laminated in this order, and the heating layer and the first insulating layer in portion X, portion Y, and portion Z are integral.

6. The sheet-like heater according to claim 1 or 2, wherein a first adhesive layer is provided between the first insulating layer and the heating layer, and the first insulating layer and the heating layer are bonded together by the first adhesive layer.

7. The sheet-like heater according to claim 5, wherein a second adhesive layer is provided between the heating layer and the second insulating layer, and the heating layer and the second insulating layer are bonded together by the second adhesive layer.

8. The sheet-type heater according to any one of claims 1 to 4, wherein the electrodes are layered.

9. A sheet-type heater according to any one of claims 1 to 4, wherein the weld strength measured by a tensile test is 20 to 50 N.

10. The sheet heater according to any one of claims 1 to 4, wherein in at least a portion of the portion Y and in the portion X, a third insulating layer is provided on the side of the first bonding auxiliary layer where the first insulating layer is absent.

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