JP2005276577A - Fusible alloy type thermal fuse - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve high temperature storing characteristics of a fusible alloy type thermal fuse which does not contain environmentally problematic noxious metal and in which an operating temperature can be set in a high temperature region. <P>SOLUTION: This is the fusible alloy type thermal fuse free from noxious metal in which the operating temperature is set within a range of 214 to 222°C and of which the main component is Sn as a low melting point fusible alloy, and by using a binary alloy with Ag added, a ternary alloy further with Cu added, a quaternary alloy further with In added, and a heat-resistant sealing material composed of a resin material to which an inorganic additive is added, and after the low melting point fusible alloy 3 connected to a pair of reed members 1, 2 is covered by a flux 4, this is constituted by housing this in an insulation case 5, and by airtightly sealing and fixing it by the heat-resistant sealing materials 6, 7. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a protective element that is sensitive to ambient temperature and prevents damage to electrical equipment, and more particularly to a lead-free fusible alloy type temperature fuse using a low melting point fusible alloy that melts at a predetermined temperature.

  As a protection element that protects electric and electronic devices from overheating damage, a thermal fuse that operates at a specific temperature and interrupts a circuit is known. Among them, the fusible alloy type thermal fuse uses a low melting point fusible alloy as a temperature sensitive material, and melts the low melting point fusible alloy provided in the energizing circuit due to an excessive rise in ambient temperature to interrupt the circuit. In addition, low melting point alloys are sometimes used together with heat generating resistors to forcibly blow low melting point soluble alloys by energizing and heating resistors, and are usually used as protective elements with built-in resistance type thermal fuses. Yes. These fusible alloy type thermal fuses are widely used as safety means for appliances such as heat insulation kotatsu, home appliances such as rice cookers, OA equipment such as liquid crystal televisions and copying machines, and lighting equipment.

  On the other hand, a low-melting-point fusible alloy as a temperature-sensitive material has conventionally been operated at a temperature of 183 ± 2 ° C. using eutectic solder 62Sn-38Pb (% by weight) even with a temperature fuse having the highest rated operating temperature. The upper limit of the recommended fuse body temperature is about 140 ° C. This was designed by setting the heat resistance temperature of the sealing resin material when the lead is led out from the insulating case in which the soluble alloy is mainly accommodated to about 150 ° C. Therefore, when using an Sn—Pb alloy that has been used for a long time, it has been difficult to produce a thermal fuse having a thermal rating equal to or higher than this temperature in terms of melting characteristics.

By the way, when using a Sn-Pb type-alloy, it has become a problem because the lead (Pb) of a composition has caused serious pollution to groundwater. Then, Pb is eluted from the waste of electrical / electronic equipment equipped with such a thermal fuse by the action of rainwater and the like, and toxic metals are leaked over a long period of time. Therefore, the use of substances harmful to the human body such as lead and cadmium is regulated, and for example, measures such as RoSH regulations for regulating specific chemical substances in Europe are required. In order to avoid such a problem, as disclosed in Patent Document 1 and Patent Document 2, lead-free thermal fuses have been proposed. However, the conventional lead-free fusible alloy type temperature fuse has a limitation in the application field because its use range is 200 ° C. or less. For example, a hair curler as a home appliance is required to have a temperature fuse with an operating temperature in the range of 215 to 225 ° C. in order to protect the electric heating part. However, there is no fusible alloy type thermal fuse with such an operating temperature, and the use of a temperature sensitive pellet type thermal fuse that uses a temperature sensitive pellet, which is usually more structurally complicated and costly, as a temperature sensitive material. I had to.
JP 2003-249155 A JP 2003-147461 A

  Therefore, it is desired to provide a fusible alloy type thermal fuse having a high operating temperature. According to the knowledge of the present inventor, the low-melting-point soluble alloy used for the thermal fuse is preferably a eutectic alloy composition having a single melting point if possible, because it is necessary to make a spherical fusing at a specific temperature. However, it was found that usable alloys can be selected and used even when the corresponding eutectic composition in the high temperature range is not found. For example, a low melting point soluble alloy made of a multi-element alloy starts to melt at a temperature equal to or higher than the solidus temperature, and completely melts at a liquidus temperature. Generally, the difference between the solidus temperature and the liquidus temperature is called the solid-liquid coexistence zone, but the smaller the solid-liquid coexistence zone, the smaller the fusing temperature variation in the thermal fuse, and the solid-liquid as a practical temperature fuse. It has been found that the coexistence zone is below 10 ° C, preferably below 5 ° C.

Furthermore, the characteristics of the thermal fuse to be mounted in series to the power supply circuit, the temperature fuse these high-temperature operation without change the internal resistance due to the high temperature storage of long, from the stable surface of the energy saving and operating temperature 2.5 × 10 ^- Preferably, the temperature fuse assembly is maintained at ⁷ Ω · m or less, and in addition, the thermal fuse assembly requires a predetermined mechanical strength or more. For example, when the diameter φ of each of the fusible alloy and the lead wire of a standard temperature fuse is 0.6 to 0.7 mm, the tensile strength of the lead wire is required to be 5.6 N or more. In order to satisfy these requirements, it is also necessary to use a heat-resistant sealing material for sealing and fixing the lead wires. In other words, in order to operate the conventional fusible alloy type thermal fuse at 200 ° C. or more, which exceeds the maximum operating temperature of 183 ° C., the long-term storage at 190 ° C. to 200 ° C., where the actual thermal environment exceeds 180 ° C. It is necessary to endure and ensure stable operation.

  Therefore, in order to solve the above-mentioned problems, the present invention does not contain harmful substances such as Pb and Cd and is within a relatively high operating temperature range, for example, an operating temperature range of 215 to 225 ° C., based on the inventors' knowledge. The object is to provide a new and improved fusible alloy type thermal fuse having a low melting point fusible alloy which can be set.

  In other words, when a lead member is derived from the insulating case, a heat-resistant sealing material is used to withstand high-temperature storage, and tin (Sn) is a main component, and a small amount of silver (Ag) for finely adjusting the operating temperature. ), Copper (Cu) and indium (In), and a new and improved fusible alloy type thermal fuse using a low melting point fusible alloy free of harmful metals. Another object of the present invention is to provide an improved fusible alloy type thermal fuse that improves the high-temperature storage characteristics by adding an inorganic substance to a resin material.

  According to the present invention, a low melting point soluble alloy is connected between one end portions of a pair of lead members and accommodated in an insulating case, and the other end portion of the lead member is hermetically fixed with a heat-resistant sealing material. It is a thermal fuse used as a lead-out terminal. The heat-resistant sealing material is made by adding an inorganic substance to the resin material, and the low-melting-point soluble alloy is a harmful metal-free material whose main component can be set at an operating temperature of 200 ° C. or higher. A fusible alloy type thermal fuse is provided. Here, the low-melting-point soluble alloy has an operating temperature composed of 2.0 to 4.0% by weight of Ag and the balance Sn firstly set to 220 ± 2 ° C. 2 to 2.5 wt% Cu containing an operating temperature set to 218 ± 2 ° C., and third containing 0.5 to 3.0 wt% In and operating temperature to 216 ± 2 ° C. Disclosed is a fusible alloy-type temperature fuse that is free of harmful metals.

  On the other hand, in order to ensure stability in high temperature storage accompanying a high operating temperature, the fusible alloy type temperature fuse of the present invention uses a heat-resistant sealing material made of a sealing resin and an inorganic additive to The insulating case is hermetically fixed and led out as an external lead. The inorganic material added to the resin material is in the range of 0.01 to 10.0 parts by weight with respect to 100 parts by weight of the resin material, and the inorganic material is inorganic nano particles having an average particle size in the range of 0.5 to 100 nm. This improves the high-temperature storage characteristics.

  Since the fusible alloy type thermal fuse of the present invention is constituted by using a specific low melting point fusible alloy and a heat-resistant sealing material, the fusible alloy type thermal fuse can be used in a relatively high temperature range of 213 to 222 ° C. and is a temperature sensitive pellet. Compared to a type thermal fuse, it is a low-cost protection element, and has industrial value such as expanding the application range to a high temperature region. Insulation case and lead member are hermetically sealed and fixed by using heat-resistant sealing material to which inorganic ultrafine particles are added, and heat resistance is improved to improve high-temperature storage characteristics and highly reliable and soluble An alloy-type thermal fuse is provided. Furthermore, since the low-melting-point fusible alloy does not contain harmful metals such as Pb and Cd, it is possible to provide a fusible alloy-type thermal fuse that is free from harmful metals and is useful for environmental conservation.

The fusible alloy type thermal fuse of the present invention can be used as various types of thermal fuses. For example, it can be used for an axial type, a radial type, a small size, a thin type, and a type with a built-in resistor, and is limited to a specific type. Is not to be done. Hereinafter, as an example of the embodiment, an axial type fusible alloy type thermal fuse will be described. Since the heat-resistant sealing material, which is a feature of the present invention, cannot be heated above the nominal operating temperature in the assembly process of the thermal fuse, a room temperature curable epoxy resin is used. In general, a room temperature curing type sealing resin does not accelerate curing by heating, and therefore, curing is completed in a state where sufficient three-dimensional network bonding is not completed, and heat resistance is inferior to heat curing type resins. However, the present invention is improved by adding inorganic ultrafine particles to compensate for this. The imperfect bonding gap of the three-dimensional network bond is filled with particles of a heat-resistant inorganic material to improve the air resistance and heat resistance of the sealing portion. As the inorganic additive, heat resistant materials such as SiO ₂ , Al ₂ O ₃ , SiC, BN, and graphite can be used. By chemically modifying the surface of these inorganic additives, dispersion in an organic medium can be facilitated and stabilized. For example, SiO ₂ has a hydroxyl group (—OH) oriented on the particle surface, and a surface in which the surface is alkyl-modified in the form of —O—R (R = alkyl group) can also be used. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, and a 2-ethylhexyl group. On the other hand, from the viewpoint of coating workability, there is a necessity that the resin fluidity before curing should not be greatly changed, and the appropriate range of the particle diameter and the addition amount has been determined. That is, when the particle size and amount of the inorganic additive are added in excess of the upper limit stipulated in the present invention, the thixotropy of the heat-resistant sealing material is large, so that the leveling property at the time of application is impaired and the inside of the soot tube is damaged. The penetration and wetting of the sealing material became insufficient, and the sealing of the ceramic soot tube was incomplete. It was also found that the application tool was not good at the time of application, and angular projections remained on the surface of the heat-resistant sealing material, thereby damaging the finished shape of the product. Similarly, when the particle size or the amount added is less than the lower limit, it has been found that the effect of addition cannot be obtained due to a very small amount. The inorganic substance is preferably spherical colloidal silica, reticulated fumed silica, or silica sol.

  Next, the fusible alloy type thermal fuse of the present invention selects the alloy composition of the temperature sensitive element according to the operating temperature. For example, a temperature fuse having an operating temperature of 220 ± 2 ° C. is realized by using a binary alloy of 2.0 to 4.0% by weight of Ag and the balance of Sn. 97Sn-3Ag (% by weight) is preferable. In this case, the temperature at which the alloy starts to melt, that is, the solidus temperature is 222 ° C., and the temperature at which the alloy completely melts, ie, the liquidus temperature is 224 ° C. FIG. 2 shows a DSC chart in this case. In other cases, for example, in the 99Sn-1Ag binary alloy in which the addition amount of Ag is less than 2.0% by weight, the melting temperature hardly changes between 231 ° C. and the melting point of Sn alone, 232 ° C., and the melting temperature decreases due to the addition of Ag. The effect of was not enough. Moreover, when the ratio of Ag with respect to Sn exceeded 5.0% by weight, the solid-liquid coexistence region increased rapidly, the stability of the fusing operation was impaired, and it was difficult to produce a product.

  Similarly, the alloy composition of the temperature sensitive element is 217 ± 2 ° C. by using a soluble alloy of 2.0 to 4.0% by weight of Ag, 0.2 to 2.5% by weight of Cu and the remaining Sn. A thermal fuse having an operating temperature is realized. In this case, the appropriate amount of Cu is in the range of 0.2 to 2.5% by weight, preferably 96.5Sn-3Ag-0.5Cu (% by weight). The ternary alloy has a solidus temperature of 218 ° C. and a liquidus temperature of 221 ° C. FIG. 3 shows a DSC chart in this case. In other cases, for example, when the addition amount of Cu is less than 0.2% by weight and 0.1% by weight, the melting temperature is 224 ° C. and the desired effect cannot be obtained, and is almost the same as the binary alloy described above. The fusing temperature was reached. Moreover, when the ratio of Cu exceeded 2.5 weight%, the solid-liquid coexistence area increased rapidly, the stability of fusing operation | movement was impaired, and product production was difficult.

  Further, the alloy composition of the temperature-sensitive material is Ag, which is 2.0 to 4.0% by weight, In is 0.5 to 3.0% by weight, Cu is 0.2 to 0.8% by weight, and the balance is Sn. By using an alloy, a thermal fuse having an operating temperature of 215 ± 2 ° C. can be realized. The appropriate amount of In for the alloy is in the range of 0.5 to 3.0 wt%, preferably 95.3Sn-3.0Ag-0.7Cu-1.0In. The alloy has a solidus temperature of 215 ° C. and a liquidus temperature of 218 ° C. FIG. 4 shows a DSC chart in this case. In other cases, for example, when the amount of In added is 0.4 wt%, which is less than 0.5 wt%, the melting temperature is 220 ° C. and the desired effect cannot be obtained, which is almost the same as the above ternary alloy. The fusing temperature was reached. In addition, when the In ratio exceeds 3.0% by weight, the solid-liquid coexistence region suddenly increases, the stability of the fusing operation is impaired, and it is difficult to produce a product.

  Hereinafter, an axial type fusible alloy type thermal fuse which is an embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, the fusible alloy type thermal fuse has a pair of lead members 1 and 2 made of Sn—Cu plated copper wire and a low melting point fusible alloy 3 which is a feature of the present invention. Joined by resistance welding. The surface of the low melting point soluble alloy 3 is coated with a flux 4 composed of rosin, wax and an activator. Thereafter, the insulating case 5 is accommodated in an insulating container or case 5 made of a ceramic soot tube such as alumina, and the lead members 1 and 2 are left by the heat-resistant sealing materials 6 and 7 made of an epoxy resin and a small amount of an inorganic additive. Constructed by sealing both ends. In the fusible alloy type thermal fuse having such a configuration, the following modifications are possible. First, regarding the shape of the low melting point soluble alloy 3, a wire of φ0.3 to 0.7 mm is usually used. However, a flat piece of a tape-like alloy having the same cross-sectional area can be used as required, and as required. Accordingly, it can be changed to φ0.7 mm or more when φ0.3 mm or less. In addition, the low melting point soluble alloy is manufactured by extruding and drawing an alloy ingot, but it can be rolled into a tape shape as necessary after that.

On the other hand, the heat-resistant sealing materials 6 and 7 are two liquids of resin material using fumed silica (SiO ₂₎ having a specific surface area of 300 m ² / g and an average particle diameter of 7 nm by BET method as an epoxy resin as a resin material and as an inorganic additive. The mixture was prepared by uniformly mixing 2.5 parts by weight of the inorganic additive with 100 parts by weight of the main agent before curing of the room temperature curing type epoxy resin. Furthermore, the lead members 1 and 2 may be changed to Ag-plated copper wire, Sn-plated copper wire, Ni-plated copper wire, or the like as required, and are not limited to Sn-Cu plated copper wires. In addition, the insulation container or case and the lead member are hermetically sealed even in various types of fusible alloy type thermal fuses such as radial type other than axial type, small and thin chip type, built-in resistor type, and package type using an insulation container. Needless to say, in the case of fixing by fixing, the above-described low melting point soluble alloy and heat-resistant sealing material can be used.

Next, specific examples of the low melting point soluble alloy will be described in detail. A low-melting-point fusible alloy was prepared by using a binary alloy having a Sn composition of 96.5% by weight and Ag of 3.5% by weight as a wire having a diameter of 0.7 mm. In Example 1, when 30 pieces were operated in the gas phase of a thermostatic chamber that was heated at a rate of 1 ° C./min while applying a detection current of 10 mA, all were within the operating temperature range of 220 ± 2 ° C. there were. Moreover, when each 10 pieces of Example 1 were stored at a high temperature of 200 ° C. for 500 hours, 1000 hours, 2000 hours and 3000 hours, respectively, and each specific resistance was tested, 4.0 × 10 ^{−3 to} 4.3. It was maintained within the range of × 10 ⁻³ Ω · m. Furthermore, the operating temperature after the high temperature storage for each time was measured and confirmed to be in the range of 220 ± 5 ° C. In Example 1, a significant improvement in the high-temperature storage life was observed as compared with Comparative Examples described later.

A fusible alloy type thermal fuse using the second low melting point fusible alloy was produced using the same heat resistant sealing material as in Example 1 described above. In Example 2, a ternary alloy having a composition of 96% by weight of Sn, 3.5% by weight of Ag, and 0.5% by weight of Cu was used as a wire having a diameter of 0.7 mm, and the fusible alloy was used as a T-temperature fuse. In Example 2, when 30 pieces were operated in the gas phase of a thermostatic chamber that was heated at a rate of 1 ° C./min while applying a detection current of 10 mA, all were within the operating temperature range of 218 ± 2 ° C. there were. Moreover, when 10 each of Example 2 was stored in high temperature of 200 degreeC for 500 hours, 1000 hours, 2000 hours, and 3000 hours, respectively, and each specific resistance was tested, 4.0 * 10 < ^-3 > -4.4. It was maintained within the range of × 10 ⁻³ Ω · m. Further, the operating temperature after the high temperature storage for each time was measured, and it was confirmed that it was within the range of 218 ± 5 ° C. In Example 2, a significant improvement in the high-temperature storage life was found compared to the comparative example described later.

Further, a fusible alloy type thermal fuse using the third low melting point fusible alloy was produced using the same heat resistant sealing material as in Example 2. In Example 3, a quaternary alloy having a composition of 95.3% by weight of Sn, 3.5% by weight of Ag, 0.7% by weight of Cu, and 1.0% by weight of In is used as a wire having a diameter of 0.7 mm. The fusible alloy made a T temperature fuse. In Example 3, when 30 pieces were operated in the gas phase of a constant temperature bath that was heated at a rate of 1 ° C./min while applying a detection current of 10 mA, all were within the operating temperature range of 216 ± 2 ° C. there were. Further, when 10 of each of Example 3 were stored at a high temperature of 200 ° C. for 500 hours, 1000 hours, 2000 hours and 3000 hours, respectively, and the specific resistance was tested, 4.0 × 10 ^{−3 to} 4.4. It was maintained within the range of × 10 ⁻³ Ω · m. Further, the operating temperature after the high temperature storage for each time was measured, and it was confirmed that it was within the range of 218 ± 5 ° C. In Example 3, a significant improvement in the high-temperature storage life was observed as compared with Comparative Examples described later.

  Hereinafter, in order to compare with each Example of this invention, the comparative example in the case of deviating from the specific range of this invention is demonstrated. First, Comparative Example 1 is a binary alloy having a composition in which the low melting point soluble alloy is the same as Example 1 in which Sn is 96.5% by weight and Ag is 3.5% by weight. A fusible alloy type thermal fuse was produced by using a conventional room temperature curing type epoxy resin as a sealing material. The comparative example 1 was stored at a high temperature of 200 ° C. and 10 pieces each stored for 500 hours, 1000 hours, 2000 hours and 3000 hours were tested. As a result, the operating temperature range of 220 ± 5 ° C. could be maintained up to 1000 hours of high-temperature storage, but it did not operate in storage for 2000 hours or more and was a defective product.

  Similarly, as Comparative Example 2, a φ0.7 mm wire is used as a ternary alloy having a composition of 96 wt% Sn, 3.5 wt% Ag, and 0.5 wt% Cu as in the second embodiment. A fusible alloy type thermal fuse of Comparative Example 2 was prepared using a conventional room temperature curing type epoxy resin as a sealing material. The comparative example 2 was stored at a high temperature of 200 ° C. and 10 pieces each stored for 500 hours, 1000 hours, 2000 hours and 3000 hours were tested. As a result, the operating temperature range of 218 ± 5 ° C. could be maintained up to 1000 hours of high-temperature storage, but it did not operate in storage for 2000 hours or more and was a defective product.

  Next, as Comparative Example 3, four compositions having the same composition as in Example 3 in which Sn was 95.3% by weight, Ag was 3.0% by weight, Cu was 0.7% by weight, and In was 1.0% by weight. Although the original alloy was used as a wire having a diameter of 0.7 mm, a fusible alloy type thermal fuse of Comparative Example 3 was produced using a conventional room temperature curing type epoxy resin as a sealing material. The comparative example 3 was stored at a high temperature of 200 ° C. and tested for 10 pieces each stored for 500 hours, 1000 hours, 2000 hours and 3000 hours. As a result, the operating temperature range of 216 ± 5 ° C. could be maintained up to 1000 hours of high-temperature storage, but it did not operate in storage for 2000 hours or more and was a defective product.

  Further, as Comparative Example 4, a Sn-Ag binary alloy was tested for a 95Sn-5Ag alloy with an Ag content of 5% by weight of 4% by weight or more. In this case, it was found that the solid-liquid coexistence region of the alloy was remarkably increased to 28.2 ° C., and the operating temperature range was 221 to 249 ° C., showing a large variation and impractical.

  Further, as Comparative Example 5, a 94Sn-3Ag-3Cu alloy in which the amount of Cu of the composition in the Sn-Ag-Cu ternary alloy was 3% by weight of 2.5% by weight or more was tested. As a result, the solid-liquid coexistence region was remarkably increased to 33.7 ° C., and the operating temperature range was 220 to 247 ° C., and the variation was not practical.

  Furthermore, in the Sn-Ag-Cu-In quaternary alloy, a comparative example using a 92.5Sn-3Ag-0.5Cu-4In alloy in which the amount of In in the composition was 3 wt% or more was 4 wt%. 6 was tested. In this case, it was found that a γ-Sn-In phase having a low melting point was generated, and the operating temperature range was 205 to 216 ° C., which showed a large variation and was not practical.

  Various characteristic values relating to thermal storage in the above-described three examples and six comparative examples are shown in a table. Table 1 is a characteristic table of three examples of the fusible alloy type thermal fuse of the example according to the present invention. Table 2 is a comparative table for comparison with the examples shown in Table 1, and is a characteristic table of six types of fusible alloy type thermal fuses.

  The heat-resistant sealing material of the present invention and a fusible alloy type thermal fuse whose operating temperature is set at 200 ° C. or more are widely used as a protective element for guaranteeing safety in household and industrial electrical equipment. Prevents equipment damage by shutting down the electrical circuit when overheating, etc., and ensures safe operation.

It is sectional drawing of the fusible alloy type | mold thermal fuse of the Example which concerns on this invention. It is a DSC chart of the binary alloy used for the fusible alloy type thermal fuse of FIG. It is a DSC chart of the ternary alloy used for the fusible alloy type thermal fuse of FIG. It is a DSC chart of the quaternary alloy used for the fusible alloy type thermal fuse of FIG.

Explanation of symbols

1, 2; Lead member 3; Low melting point soluble alloy 4; Flux 5; Insulation case (container)
6, 7; heat-resistant sealing material

Claims (6)

A temperature at which a low melting point soluble alloy is connected between one end of a pair of lead members and accommodated in an insulating case, and the other end of the lead member is hermetically fixed with a heat-resistant sealing material to form a lead-out terminal. The heat-resistant sealing material includes a resin material and an inorganic additive, and the low-melting-point soluble alloy is an alloy containing Sn as a main component and having an operating temperature of 200 ° C. or higher. There is a fusible alloy type thermal fuse. The low-melting-point soluble alloy is a binary alloy composed of 2.0 to 4.0% by weight of Ag and the balance being Sn, and the operating temperature is set at about 220 ° C. A fusible alloy type temperature fuse. The fusible alloy according to claim 2, wherein the low-melting-point fusible alloy is a ternary alloy containing 0.2 to 2.5% by weight of Cu, and the operating temperature is set to approximately 218 ° C. Mold temperature fuse. The fusible alloy according to claim 3, wherein the low-melting-point fusible alloy is a quaternary alloy containing 0.5 to 3.0% by weight of In, and the operating temperature is set to approximately 216 ° C. Mold temperature fuse. The fusible alloy mold temperature according to claim 1, wherein the inorganic additive of the heat-resistant sealing material is in a range of 0.01 to 10.0 parts by weight with respect to 100 parts by weight of the resin material. Fuse. 6. The fusible alloy type temperature fuse according to claim 5, wherein the inorganic additive has an average particle diameter of 0.5 to 100 nm.

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