JP6395315B2 - Thermal fuse ink, thermal fuse and heater using the same, and method for manufacturing thermal fuse using thermal fuse ink - Google Patents

Description

  The present invention relates to a thermal fuse ink capable of forming a thermal fuse by printing, a thermal fuse and a heater using the ink, and a thermal fuse manufacturing method using the thermal fuse ink.

  In an apparatus that generates heat during operation, when the ambient temperature rises above a predetermined level, it is required to prevent the excessive temperature rise and ensure safety by cutting off the wiring. For example, Patent Document 1 discloses a conductor cutting device, a reaction device, a fuel cell, a fuel cell device, an electronic device, and a conductor cutting method that can automatically stop operation when a predetermined temperature is reached. ing.

  FIG. 9 is a schematic diagram showing the internal structure of the reaction device 930. FIG. 10 is a schematic cross-sectional view showing a thin-film cutting material 964 using a sublimable material, FIG. 10 (a) is a schematic cross-sectional view showing the thin-film cutting material 964 during normal operation, and FIG. It is a schematic cross section when it rises to a predetermined temperature.

  As shown in FIG. 9, the thin film cutting material 963 is located at a position partially overlapping with the thin film conductor 961, and the thin film cutting material 964 is located at a position partially overlapping with the thin film conductor 962, as shown in FIG. The insulating films 955 and 956 are buried. The thin-film cutting materials 963 and 964 peel a part of the thin-film conductors 961 and 962 that overlap each other when the temperature exceeds a certain temperature from the reactor main body 950.

  As the material of the thin-film cutting materials 963 and 964, a material that does not deform at a temperature during normal operation but deforms when the temperature rises to a predetermined temperature dissociated from that during normal operation can be used. For example, a material that expands or contracts larger than the reactor main body 950 when the temperature rises to a predetermined temperature can be used. Alternatively, a material that melts or sublimes when it is raised to a predetermined temperature can be used.

  For example, in the reactor main body 950 using a material that sublimes, as shown in FIG. 10, the volume of the thin-film cutting material 964 sublimates when it reaches a predetermined temperature or more, and the volume rapidly increases due to gas, resulting in the insulation of the upper layer. The film 956 and the thin film conductor 962 are broken.

JP 2009-70721 A

  However, since a sublimable material is sandwiched between two insulating films and wiring is provided on the upper surface of the upper insulating film, the structure is complicated and many processes are required, so that the manufacturing is complicated. there were.

  SUMMARY OF THE INVENTION The present invention solves the above-described problems, and a thermal fuse ink capable of forming a thermal fuse by printing, a thermal fuse and a heater using the thermal fuse, and a thermal fuse manufacturing using the thermal fuse ink It aims to provide a method.

  The temperature fuse ink of the present invention is an ink prepared so as to be printable, and a conductive substance that can be vaporized in an environment at a predetermined temperature or higher after printing, and a temperature at which the conductive substance is vaporized. An insulating material having a lower softening point, and a binder for dispersing and holding the conductive material and the insulating material, and the conductive material forms an electric conduction path by printing. Forming a support capable of holding the conductive material even in an environment where the insulating material is at a temperature equal to or higher than the temperature at which the binder disappears, and the conductive material is more effective than the insulating material in the environment above the predetermined temperature. It is characterized by vaporizing first.

  A support capable of holding the conductive material is formed even in an environment where the insulating material is at or above the temperature at which the binder disappears, and the conductive material is vaporized earlier than the insulating material in the environment at or above the predetermined temperature. It is possible to prepare an ink for a thermal fuse that breaks in an environment at or above the temperature. This makes it possible to configure a thermal fuse by printing.

  In the thermal fuse ink of the present invention, the insulating substance has a thermal expansion coefficient of 3 to 15 ppm / ° C. and a softening point of 450 ° C. or less.

  According to this configuration, it is possible to form a support that easily vaporizes the conductive substance.

  In the thermal fuse ink of the present invention, the main component of the conductive material is carbon black powder, the main component of the insulating material is glass powder, and the main component of the binder is ethyl cellulose resin. Features.

  According to this configuration, even if the ethyl cellulose resin burns and disappears at 300 to 400 ° C., the glass powder retains the carbon black powder, and the carbon black powder burns and vaporizes at 500 ° C. or higher. It is possible to print a thermal fuse in which the electric conduction path disappears when the above temperature is reached.

  The thermal fuse of the present invention is a thermal fuse formed on a substrate having a wiring part on at least one surface, and the conductive material is printed on the one surface by printing the above thermal fuse ink. The electrical conduction path to be formed is electrically connected to the wiring portion.

  According to this configuration, a thermal fuse that breaks at a predetermined temperature or more can be easily formed by electrically connecting the wiring portion and the printed conductive material of the thermal fuse ink.

  The substrate includes a heating element that generates heat when energized, and the temperature fuse is a temperature fuse arranged in a range overlapping the heating element in plan view on the one surface of the substrate, wherein the heat generation It is preferable to be formed to have the same width as the body or a narrower width.

  According to this configuration, the heating element is arranged so as to overlap with the heating element in a plan view, and is formed to have the same width as the heating element or a narrower width. Therefore, the temperature distribution when heat is transferred from the heating element to the thermal fuse Less is. Therefore, the thermal fuse can be operated with high accuracy with respect to the temperature of the heating element.

  Further, the heating element is provided on the other surface of the substrate, and the thermal fuse is disposed in a range where the thermal fuse ink is printed on the one surface and overlaps the heating element in a plan view. Is preferred.

  According to this configuration, even when the thermal fuse is operated with respect to the temperature of the heating element, foreign matter or the like is not scattered on the heating element side.

  In addition, it is preferable that the thermal fuse has a plurality of regions on which the thermal fuse ink is printed, and is divided and disposed in a range where the region overlaps the heating element in plan view.

  According to this configuration, since the region to be printed is divided and disposed, even when the thermal expansion coefficient of the thermal fuse is different from that of the substrate or the heating element, deformation due to thermal expansion is reduced.

  The heater of the present invention is a heater having an electrical path for energizing the heating element, the heating element being capable of raising the temperature to a temperature lower than the predetermined temperature, and including the temperature fuse. The thermal fuse is connected to the middle of the electrical path through the wiring portion.

  According to this configuration, since the temperature fuse is provided in the electrical path for energizing the heating element, the temperature fuse can cut off the energization to the heating element when the heater is heated to a predetermined temperature or more due to excessive heating of the heater.

  The method for manufacturing a thermal fuse of the present invention is a method for manufacturing a thermal fuse formed on a substrate having a wiring portion, wherein the thermal fuse ink is printed, the binder disappears, and the insulating substance is removed. Baking is performed at a baking temperature for forming a support capable of holding the conductive material, and the insulating material is melted to integrally form a film containing the conductive material on the substrate.

  According to this configuration, since the thermal fuse ink is formed by printing and firing, it is easy to manufacture the thermal fuse.

  In the method for manufacturing a thermal fuse of the present invention, the firing temperature is higher than a temperature at which the binder disappears, higher than the softening point of the insulating material, and lower than the predetermined temperature. .

  According to this configuration, by setting the firing temperature of the thermal fuse ink to an optimum temperature for manufacturing, it is possible to manufacture a thermal fuse with little variation in characteristics.

  The ink for a thermal fuse of the present invention includes a conductive substance that can be vaporized in an environment of a predetermined temperature or higher, an insulating substance having a softening point lower than the temperature at which the conductive substance is vaporized, A binder that is dispersed and held, and is prepared to be printable. A support capable of holding the conductive material is formed even in an environment where the insulating material is at or above the temperature at which the binder disappears, and the conductive material is vaporized earlier than the insulating material in the environment at or above the predetermined temperature. It is possible to form a thermal fuse that breaks in an environment at or above the temperature. Accordingly, it is possible to provide a thermal fuse ink that can form a thermal fuse by printing.

  In addition, by using the thermal fuse ink of the present invention, the wiring portion provided on one surface of the substrate is electrically connected to the conductive material of the printed thermal fuse ink so that the temperature exceeds a predetermined temperature. A thermal fuse that breaks can be easily formed.

  Furthermore, since the heater having the above-described temperature fuse includes a temperature fuse in an electric path for energizing the heating element, when the heater is heated to a predetermined temperature or more due to excessive heating of the heater, the temperature fuse is transferred to the heating element. Can be turned off.

  The method for manufacturing a thermal fuse of the present invention prints the thermal fuse ink, fires at a firing temperature at which the binder disappears and the insulating material forms a support capable of holding the conductive material, and melts the insulating material. Thus, a film containing a conductive substance is integrally formed on the substrate. Since the thermal fuse ink is formed by printing and baking, it is easy to manufacture the thermal fuse.

FIG. 1A is a schematic diagram illustrating a thermal fuse according to an embodiment of the present invention, FIG. 1A is a schematic plan view of one side of a substrate, and FIG. 1B is a perspective view of the other side of the substrate. It is the seen schematic diagram. It is the schematic cross section cut | disconnected by the II-II line | wire of Fig.1 (a). It is explanatory drawing of the ink for thermal fuses used in order to print a thermal fuse. FIG. 4A is an explanatory diagram showing a method for manufacturing a thermal fuse, FIG. 4A is an explanatory diagram showing a substrate before printing, and FIG. 4B is a diagram showing a state in which thermal fuse ink is applied to the substrate by printing. It is explanatory drawing. It is explanatory drawing which shows the state heated after application | coating, FIG. 5 (a) is explanatory drawing which shows the state heated at the temperature which a solvent volatilizes, FIG.5 (b) is the state heated at the temperature which a binder lose | disappears. It is explanatory drawing which shows. FIGS. 6A and 6B are explanatory views showing a manufactured thermal fuse, FIG. 6A is an embodiment of the present invention, and FIG. 6B is a modified example of the present invention. It is a block diagram which shows the heater of embodiment of this invention. It is a graph which shows the relationship between heating temperature and resistance value. 2 is a schematic diagram showing an internal structure of a reaction apparatus described in Patent Document 1. FIG. It is a schematic cross section which shows the thin film cutting material using the sublimable material of patent document 1, FIG. 10 (a) is a schematic cross section which shows the thin film cutting material at the time of normal operation, FIG.10 (b) is FIG. It is a schematic cutaway view when it rises to a predetermined temperature.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. For easy understanding, the dimensions of the drawings are appropriately changed.

[First Embodiment]
FIG. 1 is a schematic plan view showing a thermal fuse 1 according to an embodiment of the present invention. FIG. 1A is a schematic view of one surface 20a of a substrate 20, and FIG. 6 is a schematic view of the other surface 20b seen through. FIG. 2 is a schematic cross-sectional view taken along the line II-II in FIG. FIG. 3 is an explanatory diagram of the thermal fuse ink 60 used for printing the thermal fuse 1. 4A and 4B are explanatory views showing a method of manufacturing the thermal fuse 1, FIG. 4A is an explanatory view showing the substrate 20 before printing, and FIG. 4B is a substrate where the thermal fuse ink 60 is printed. It is explanatory drawing which shows the state apply | coated to 20. FIG. FIG. 5 is an explanatory view showing a state of being heated after coating, FIG. 5 (a) is an explanatory view showing a state of being heated at a temperature at which the solvent volatilizes, and FIG. 5 (b) is a temperature at which the binder disappears. It is explanatory drawing which shows the state heated. 6A and 6B are explanatory views showing the manufactured thermal fuse, FIG. 6A is an embodiment of the present invention, and FIG. 6B is a modification of the present invention. FIG. 7 is a block diagram showing the heater according to the embodiment of the present invention. FIG. 8 is a graph showing the relationship between the heating temperature and the resistance value.

(Thermal fuse)
The thermal fuse 1 of the present embodiment is formed on one surface 20a of the substrate 20 as shown in FIGS. The substrate 20 includes a wiring portion 25 on one surface 20a, and a heating element 30 and an electric path 40 for energizing the heating element 30 on the other surface 20b (FIG. 1B). The thermal fuse 1 is formed on one surface 20a of the substrate 20 (FIG. 1A), but is disposed in a region A1 within a range overlapping with the heating element 30 formed on the other surface 20b in plan view. Is done.

  The substrate 20 is made of an insulating flat material such as a glass substrate or an alumina substrate. The wiring part 25 is, for example, a conductive metal pattern.

  The heating element 30 is used as a heat source of a toner fixing device, for example. The toner fixing device fixes the toner on the recording paper by applying heat and pressure to the toner disposed on the recording paper. The electrical path 40 is, for example, a wiring or a connector connected to the control unit of the toner fixing device.

  As shown in FIG. 2, the thermal fuse 1 is divided into thermal fuses 1 a, 1 b, and 1 c, and both ends of each are stacked on the wiring portion 25. Note that a protective film may be provided on one surface 20 a of the substrate 20 so as to cover the wiring portion 25. Further, it is preferable to provide a protective film on the other surface 20 b of the substrate 20 so as to cover the heating element 30.

  The thermal fuse 1 is formed on one surface 20a of the substrate 20 by printing. The thermal fuse ink 60 used for printing has the following characteristics.

(Ink for thermal fuse)
As shown in FIG. 3, the thermal fuse ink 60 of this embodiment includes a conductive material 12, an insulating material 11, and a binder 14 that holds the conductive material 12 and the insulating material 11 in a dispersed manner. It is an ink that is prepared so as to be printable with a solvent.

  The binder 14 is a synthetic resin mainly composed of ethyl cellulose resin. As the solvent in this case, terpineol, butyl carbitol acetate, or carbitol acetate is preferably used.

  The conductive substance 12 is made of a material that is fired after printing in the state of the thermal fuse ink 60 to form an electric conduction path P12 (see FIG. 5) and can be vaporized in an environment of a predetermined temperature or higher. Selected. Carbon black powder, which is a material that vaporizes at a relatively high temperature, is used for the conductive substance 12 in the thermal fuse ink 60 of the present embodiment. The carbon black powder is fine particles of carbon having a diameter of about 3 to 500 nm and has conductivity. In air at atmospheric pressure, the carbon black powder reacts with oxygen at an environmental temperature of 500 ° C. or higher, and burns and vaporizes.

  The insulating substance 11 forms a support 13 (see FIG. 5) that can hold the conductive substance 12, and is selected from a heat-resistant insulating material in which the conductive substance 12 vaporizes first in an environment of a predetermined temperature or higher. Is done. Glass powder having a relatively low softening point is used for the insulating substance 11 in the thermal fuse ink 60 of the present embodiment.

  The solvent is preferably a solvent that has low volatility during printing and uniformly disperses the insulating substance 11 and the conductive substance 12. In addition, it is preferable that the binder 14 disappears and the insulating material 11 volatilizes at a temperature equal to or lower than the firing temperature at which the support 13 is formed.

  In this way, the thermal fuse ink 60 suitable for printing is prepared.

(Method for manufacturing thermal fuse)
The thermal fuse 1 of this embodiment is manufactured by the steps shown in FIGS.

  The thermal fuse ink 60 shown in FIG. 3 is applied to one surface 20a of the substrate 20 shown in FIG. 4A by printing. The printing method is not limited, but the viscosity and the like are appropriately adjusted depending on the method. As shown in FIG. 4B, the thermal fuse 1 of the present embodiment is arranged by dividing the area A1 printed with the thermal fuse ink 60 into a plurality (three in FIG. 4).

  As shown in FIG. 5 (a), the binder 14 contracts at a temperature at which the temperature fuse ink 60 is applied to the substrate 20 by printing and then heated to evaporate the solvent. In order to use as the thermal fuse 1, it is fired at a higher temperature. The firing temperature is higher than the temperature at which the binder 14 disappears and higher than the softening point of the insulating substance 11. At this time, as shown in FIG. 5B, the binder 14 contained in the thermal fuse ink 60 disappears. On the other hand, since the firing temperature is higher than the softening point of the insulating substance 11, even if the ethyl cellulose resin, which is the main component of the binder 14, disappears, the insulating substance 11 is softened and connected to a network. Configure. Since the insulating substance 11 forms the support 13, the conductive substance 12 can be held.

  Therefore, the insulating material 11 can be melted and a film containing the conductive material 12 can be integrally formed on the substrate 20. The conductive substance 12 forms an electric conduction path P12 and is in a state where it can be energized.

  In the present embodiment, as shown in FIG. 6A, the thermal fuse 1 is divided and formed on one surface 20 a of the substrate 20, and both ends overlap the wiring portion 25. As a result, the thermal fuses 1a, 1b, and 1c function independently for each of the divided regions, and each of them breaks, whereby the conduction of the respective wiring portions 25 can be cut off. Further, as shown in FIG. 6B, the divided thermal fuses 1 a, 1 b, and 1 c may be connected in series by a wiring portion 25. In this case, if any one breaks, the entire conduction can be cut off.

  By setting the firing temperature of the thermal fuse ink 60 to an optimum temperature for manufacturing, the thermal fuse 1 with little variation in characteristics can be manufactured.

  Since the thermal fuse ink 60 is formed by printing and firing, it is easy to manufacture the thermal fuse 1.

(heater)
The heater 100 of the present embodiment can be heated as a heat source of the toner fixing device, for example, and includes an electric path 40 for energizing the heating element 30 as shown in FIG. The thermal fuse 1 is connected in the middle of the electrical path 40. In the case of a toner fixing device, the heating element 30 is used at a relatively high temperature (400 ° C.). The electrical path 40 is a power path composed of wiring, a connector, and the like from a power supply unit (not shown).

  The thermal fuse 1 is used as a safety device that electrically connects the electrical conduction path P12 formed by the conductive material 12 to the wiring part 25 and cuts off the power supply to the wiring part 25 at a predetermined temperature or higher. The heater 100 according to the present embodiment includes the thermal fuse 1 in the electrical path 40 through which the heating element 30 is energized. Therefore, when the heater 100 is heated to a predetermined temperature or higher due to overheating of the heater 100, the thermal fuse 1 is heated. The power supply to 30 can be cut off. In the case of a toner fixing device, the predetermined temperature that needs to be interrupted is about 500 ° C., and it is difficult to apply a temperature fuse that breaks at 200 ° C. to 300 ° C. The thermal fuse 1 provided in the heater 100 according to the present embodiment is assumed to be broken at a higher temperature.

  In addition, the substrate 20 includes a heating element 30 that generates heat when energized, and the thermal fuse 1 is disposed within a range overlapping the heating element 30 in plan view on one surface 20a of the substrate 20 and has the same width as the heating element 30 or the same. It is formed with a narrower width.

  According to this configuration, the thermal fuse 1 is arranged so as to overlap the heating element 30 in plan view, and is formed to have the same width as the heating element 30 or a narrower width. There is little temperature distribution when heat is transferred. Therefore, the thermal fuse 1 can be accurately operated with respect to the temperature of the heating element 30.

  Further, the heating element 30 is provided on the other surface 20b of the substrate 20, and the temperature fuse 1 is disposed in a range where the temperature fuse ink 60 is printed on the one surface 20a and overlaps the heating element 30 in plan view.

  According to this configuration, even when the thermal fuse 1 is operated with respect to the temperature of the heating element 30, foreign matter or the like is not scattered on the heating element 30 side disposed on the other surface 20 b of the substrate 20.

A thermal fuse ink 60 having the following composition was printed on the substrate 20 having the wiring portion 25 formed on one surface 20a.
Carbon black powder (Sheet 9 made by Tokai Carbon Co., Ltd.) 6.3 wt%
Glass powder (glass frit GF3410 manufactured by Okuno Pharmaceutical Co., Ltd.) 56.3 wt%
Ethyl cellulose resin and solvent mixture 37.5 wt%

  Then, the relationship between heating temperature and the resistance value measured by the wiring part 25 was investigated by heating with a baking furnace. As shown in FIG. 8, the measured resistance value decreased with heating from an unfired state after printing to about 400 ° C. This seems to indicate that the ethyl cellulose resin hinders electric conduction, but the electric conduction path P12 of the carbon black powder is formed. Moreover, in the state baked with the calcination temperature of about 300 to 400 degreeC, it is thought that resistance value becomes the smallest and the ethylcellulose resin burns and disappears. It was confirmed that the resistance value suddenly increased from around 500 ° C. when heated at a higher temperature. This is presumably due to the fact that the carbon black powder burns and vaporizes at 500 ° C. or higher, so that the electric conduction path P12 disappears when the temperature reaches 500 ° C. or higher.

  Even if the ethyl cellulose resin disappears at 300 to 400 ° C., the thermal fuse 1 is not peeled off from the substrate 20. This is because glass powder having a softening point of 450 ° C. or less is used, and the support 13 in which the glass powder is partially melted and connected in a mesh form at a temperature at which the ethyl cellulose resin burns and disappears. Presumed to be composed.

  The glass powder is optimally one having a softening point of 450 ° C. or less and a thermal expansion coefficient of about 3 ppm / ° C., but preferably has a thermal expansion coefficient of 15 ppm / ° C. or less. Thereby, the support body 13 which is easy to vaporize the electroconductive substance 12 can be formed.

  The carbon black powder used as the conductive material 12 is surely vaporized in the fine particle type.

  Even after the carbon black powder is vaporized, the support 13 mainly composed of the glass powder remains without being vaporized.

  When the thermal expansion is large, the warp of the substrate 20 becomes too large, and thus the thermal fuse 1 is arranged by dividing the area A1 to be printed. Since the area A1 to be printed is divided and arranged, the entire warp is reduced even when the thermal expansion is large. Thereby, even when the thermal expansion coefficient of the thermal fuse 1 is different from that of the substrate 20 and the heating element 30, deformation due to thermal expansion is reduced.

  Hereinafter, the effect by having set it as this embodiment is demonstrated.

  The thermal fuse ink 60 of the present embodiment is an ink prepared so as to be printable. After printing, the conductive material 12 that can be vaporized in an environment of a predetermined temperature or higher, the insulating material 11 having a softening point lower than the temperature at which the conductive material 12 is vaporized, and the conductive material 12 are insulated. And a binder 14 for dispersing and holding the active substance 11. The conductive material 12 forms the electric conduction path P12 by printing, and the support 13 capable of holding the conductive material 12 is formed even in an environment higher than the temperature at which the insulating material 11 disappears from the binder 14. In the above environment, the conductive substance 12 is vaporized earlier than the insulating substance 11.

  The support 13 capable of holding the conductive material 12 is formed even in an environment where the insulating material 11 is at or above the temperature at which the binder 14 disappears, and the conductive material 12 precedes the insulating material 11 in the environment at a predetermined temperature or higher. Since it vaporizes, it breaks in an environment of a predetermined temperature or higher. Thereby, the thermal fuse 1 can be configured by printing.

  In the thermal fuse ink 60 of the present embodiment, the insulating substance 11 preferably has a thermal expansion coefficient of 3 to 15 ppm / ° C. and a softening point of 450 ° C. or less.

  According to this configuration, it is possible to form the support 13 that easily vaporizes the conductive substance 12.

  In the thermal fuse ink 60 of this embodiment, the main component of the conductive material 12 is carbon black powder, the main component of the insulating material 11 is glass powder, and the main component of the binder 14 is ethyl cellulose resin. It is preferable.

  According to this configuration, even if the ethyl cellulose resin burns and disappears at 300 to 400 ° C., the glass powder holds the carbon black powder, and the carbon black powder burns and vaporizes at 500 ° C. or higher. As a result, it is possible to print a thermal fuse in which the electric conduction path P12 disappears when the temperature reaches 500 ° C. or higher.

  Further, the thermal fuse 1 of the present embodiment is formed on the substrate 20 having the wiring portion 25 on at least one surface 20a. The thermal fuse ink 60 is printed on one surface, and the electrical conduction path P12 formed by the conductive material 12 is electrically connected to the wiring portion 25.

  According to this configuration, the thermal fuse 1 that breaks at a predetermined temperature or more can be easily formed by electrically connecting the wiring portion 25 and the printed conductive material 12 of the thermal fuse ink 60.

  In addition, the substrate 20 includes a heating element 30 that generates heat when energized, and the thermal fuse 1 is disposed within a range overlapping the heating element 30 in plan view on one surface 20a of the substrate 20 and has the same width as the heating element 30 or the same. It is preferable that it is formed with a narrow width.

  According to this configuration, the thermal fuse 1 is arranged so as to overlap the heating element 30 in plan view, and is formed to have the same width as the heating element 30 or a narrower width. There is little temperature distribution when heat is transferred. Therefore, the thermal fuse 1 can be accurately operated with respect to the temperature of the heating element 30.

  Further, the heating element 30 is provided on the other surface 20b of the substrate 20, and the temperature fuse 1 is disposed in a range where the temperature fuse ink 60 is printed on the one surface 20a and overlaps the heating element 30 in plan view.

  According to this configuration, even when the thermal fuse 1 is operated with respect to the temperature of the heating element 30, foreign matter or the like is not scattered on the heating element 30 side.

  Also, there are a plurality of regions A1 on which the thermal fuse ink 60 is printed, and the regions A1 are divided and arranged in a range overlapping the heating element 30 in plan view.

  According to this configuration, since the printed area A1 is divided and disposed, even when the thermal expansion coefficient of the thermal fuse 1 is different from that of the substrate 20 and the heating element 30, deformation due to thermal expansion is reduced.

  In addition, the heater 100 according to the present embodiment includes an electric path 40 for energizing the heating element 30 so that the heating element 30 can be heated to a temperature lower than a predetermined temperature. The heater 100 includes the above-described thermal fuse 1, and the thermal fuse 1 is connected in the middle of the electrical path 40 through the wiring portion 25.

  According to this configuration, the temperature fuse 1 is provided in the electric path 40 for energizing the heating element 30, so that when the heater 100 is heated to a predetermined temperature or higher due to excessive temperature rise of the heater 100, the temperature fuse 1 is transferred to the heating element 30. Can be turned off.

  The method for manufacturing the thermal fuse 1 of the present embodiment is a method for manufacturing the thermal fuse 1 formed on the substrate 20 having the wiring portion 25, and prints the thermal fuse ink 60 described above. Subsequently, the binder 14 disappears and the insulating material 11 is baked at a baking temperature to form a support 13 capable of holding the conductive material 12, and the insulating material 11 is melted to contain the conductive material 12. Are integrally formed on the substrate 20.

  According to this configuration, since the thermal fuse ink 60 is formed by printing and baking, the thermal fuse 1 can be easily manufactured.

  In the method for manufacturing the thermal fuse 1 according to this embodiment, the firing temperature is preferably higher than the temperature at which the binder 14 disappears, higher than the softening point of the insulating material 11, and lower than a predetermined temperature.

  According to this configuration, by setting the firing temperature of the thermal fuse ink 60 to an optimum temperature for manufacturing, the thermal fuse 1 with little variation in characteristics can be manufactured.

  As described above, the embodiment of the present invention has been specifically described. However, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. . For example, the present invention can be modified as follows, and these also belong to the technical scope of the present invention.

  (1) In the present embodiment, the heating element 30 is disposed on the other surface 20b of the substrate 20, but the heating element 30 and the thermal fuse 1 may be stacked on the one surface 20a. Good. For example, in the toner fixing device, the other surface 20b of the substrate 20 serves as a heater surface, and the toner is fixed by heat transmitted from the heating element 30 to the other surface 20b.

  (2) In the present embodiment, the number of divisions of the thermal fuse 1 is matched with the number of divisions of the heating element 30 and the respective lengths are matched. However, the number of divisions of the thermal fuse 1 may be further increased. In order to reduce the warpage of the substrate 20 due to thermal expansion, it is effective to increase the number of divisions of the thermal fuse 1.

  (3) In the present embodiment, the main component of the binder 14 is ethyl cellulose resin, but any synthetic resin material that disappears by combustion at a firing temperature lower than a predetermined temperature is applicable. In addition to the carbon black powder, the conductive substance 12 may be selected from conductive materials that burn or sublime in an environment at a predetermined temperature or higher.

DESCRIPTION OF SYMBOLS 1, 1a, 1b, 1c Thermal fuse 11 Insulating substance 12 Conductive substance 13 Support body 14 Binder 20 Substrate 20a One side 20b The other side 25 Wiring part 30 Heating element 40 Electrical path 60 Thermal fuse ink 100 Heater A1 area | region

Claims (10)

An ink prepared to be printable,
A conductive material that can be vaporized in an environment at a predetermined temperature or higher after printing, an insulating material having a softening point lower than the temperature at which the conductive material is vaporized, and the conductive material and the insulating material. A binder for dispersing and holding the substance,
The conductive substance forms an electric conduction path by printing, and forms a support capable of holding the conductive substance even in an environment at a temperature higher than the temperature at which the insulating substance disappears,
The thermal fuse ink, wherein the conductive material is vaporized earlier than the insulating material in an environment of the predetermined temperature or higher.   2. The thermal fuse ink according to claim 1, wherein the insulating substance has a thermal expansion coefficient of 3 to 15 ppm / ° C. and the softening point is 450 ° C. or less.   The main component of the conductive material is carbon black powder, the main component of the insulating material is glass powder, and the main component of the binder is ethyl cellulose resin. The thermal fuse ink described. A thermal fuse formed on a substrate having a wiring portion on at least one surface,
The thermal fuse ink according to any one of claims 1 to 3 is printed on the one surface,
A thermal fuse, wherein an electrical conduction path formed by the conductive material is electrically connected to the wiring portion. The substrate includes a heating element that generates heat when energized, and is a thermal fuse disposed in a range overlapping the heating element in plan view on the one surface of the substrate,
5. The thermal fuse according to claim 4, wherein the thermal fuse is formed to have the same width as the heating element or a narrower width.   The heating element is provided on the other surface of the substrate, the thermal fuse ink is printed on the one surface, and the heating element is disposed in a range overlapping the heating element in a plan view. Thermal fuse described.   The area where the thermal fuse ink is printed is plural, and the area is divided and arranged in a range overlapping the heating element in plan view. Thermal fuse described in. An electrical path for energizing the heating element;
The heater is capable of raising the temperature to a temperature lower than the predetermined temperature,
A heater comprising the thermal fuse according to any one of claims 5 to 7, wherein the thermal fuse is connected in the middle of the electrical path via the wiring portion. A method of manufacturing a thermal fuse formed on a substrate having a wiring part,
Printing the thermal fuse ink according to any one of claims 1 to 3,
The binder disappears and the insulating material is baked at a baking temperature to form a support capable of holding the conductive material,
A method of manufacturing a thermal fuse, comprising melting the insulating material and integrally forming a film containing the conductive material on the substrate. The method for manufacturing a thermal fuse according to claim 9, wherein the firing temperature is higher than a temperature at which the binder disappears, higher than the softening point of the insulating material, and lower than the predetermined temperature.