JP3409190B2 - Fuse resistor - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin fuse resistor which can be mounted in a limited space such as inside a battery, and a fuse resistor composition for obtaining the fuse resistor.

[0002]

2. Description of the Related Art In recent years,
The technological progress of batteries has been remarkable, and secondary batteries, which can be charged and discharged from primary batteries, have come to be used even in batteries widely used in general households. As the secondary battery, nickel / cadmium battery, nickel / hydrogen battery,
Lithium ion batteries and the like are commercially available.

Since a relatively large current flows through the secondary battery during charging, an overcurrent may flow due to a failure of the charger, and at such a time, due to the internal resistance of the secondary battery, etc. There is a risk that Joule heat will be generated and eventually cause an explosion.

Therefore, it is conceivable to mount a fuse resistor, which is a protection element for preventing overcurrent, inside the secondary battery. Conventionally, there is a fuse resistor using a metal wire and the like, but a fuse resistor that can be mounted in a limited space inside the secondary battery has not been proposed yet.

In view of the above problems, an object of the present invention is to obtain a thin fuse resistor which can be mounted in a limited space such as the inside of a battery.

[0006]

[Means for Solving the Problems]

[0007]

[0008]

Further, the present invention fuse resistor 4 for example
As shown in FIG. 3, the metal foil electrodes 6a and 6b are provided on both surfaces of the porous metal plate 5 with an adhesive 7 containing thermally expandable microcapsules.
The fuse resistor is laminated on the
When the temperature exceeds the thermal expansion temperature of the expandable microcapsules, the heat
The expandable microcapsule expands and the porous metal plate and metal
This is for cutting the conduction between the foil electrodes .

[0010] The present invention fuse resistors as shown in FIG. 3, for example, a plurality of electrode patterns 9 formed on the substrate 8
A conductive paint layer 1 is provided so as to provide a material layer 10 containing thermally expandable microcapsules between a and 9b and to straddle the material layer 10 to connect the electrode patterns 9a and 9b.
1 is a fuse resistor having a thickness of a material layer d.
The relationship between ₀ and the thickness d ₁ of the conductive coating layer is d ₀ / d ₁ ≧ 0.2
And the temperature between the electrode patterns is
Above the thermal expansion temperature of the cell, the thermal expansion microcapsule
The cell expands and breaks through the conductive paint layer . Well
In addition, the fuse resistor of the present invention has a metal plate on both sides of the porous metal plate.
Adhesive containing metal foil electrodes containing thermally expandable microcapsules
The metal foil electrode is partly laminated with the porous metal.
It comes into contact with a plate. Further, the fuse resistor of the present invention
Has a thermal expansion property between multiple electrode patterns formed on the substrate.
While providing a material layer containing microcapsules
As if connecting the plurality of electrode patterns across the material layer
A conductive paint layer is formed.

[0011]

According to the present invention, when an overcurrent flows and heat is generated, the heat-expandable microcapsule expands, disconnects the conductive path, and operates as a fuse resistor and can be mounted in a limited space such as inside a battery. A thin fuse resistor can be obtained.

[0012]

EXAMPLES Examples of the fuse resistance composition and the fuse resistor of the present invention will be described below with reference to the drawings. Figure 1
1 indicates a layer of the fuse resistance composition according to the present example, and the fuse resistor according to the present example has the fuse resistance composition layer 1 between the metal electrodes 2a and 2b of nickel, aluminum or the like as shown in FIG. It is provided.

The fuse resistance composition constituting the fuse resistance composition layer 1 is composed of thermoplastic resin 12 with metal particles,
Conductive particles 13 such as carbon particles and thermally expandable microcapsules 14 are dispersed.

The thermally expandable microcapsules 14 have a hollow resin particle containing a low boiling point hydrocarbon and a particle size of 10
It is a microsphere of μm to 30 μm. In this case, the expansion temperature of the thermally expandable microcapsules 14 can be controlled by adjusting the softening temperature of the hollow resin particles. Further, the thermoplastic resin 12 is preferably softened or rubber-like at the expansion temperature of the heat-expandable microcapsules 14, and acrylic, polyester, urethane or the like can be used.

Next, Examples 1 to 10 and Comparative Example 1 of the fuse resistor as shown in FIG. 1 will be described. The metal electrodes 2a and 2b of Examples 1 to 10 and Comparative Example 1, respectively.
Is an electrolytic Ni foil (65 μm) manufactured by Fukuda Metal Foil & Powder Co., Ltd., and polyester UE3220 manufactured by Unitika Ltd. is used as the resin 12 of the fuse resistance composition.

In Examples 1 to 10 and Comparative Example 1, the conductive particles 13 and the thermally expandable microcapsules 14 shown in Table 1 were dispersed in the solution of the resin 12, and the metal electrodes 2a,
The Ni foil of 2b was coated and then dried, and the temperature within the expansion temperature of the thermally expandable microcapsules 14 was applied to obtain the total element thickness shown in Table 1.

In this Example 1, carbon particles XC having a particle size of 0.03 μm manufactured by Cablack Co., Ltd. were used as the conductive particles 13.
-72 and a thermally expandable microcapsule 14 manufactured by Matsumoto Yushi Co., Ltd. having an expansion temperature of 100 ° C. to 105 ° C.
Using 50D, 150 parts by weight of the conductive particles 13 and 20 parts by weight of the heat-expandable microcapsules 14 were dispersed in 100 parts by weight of the resin 12, and the total element thickness was set to 250 μm.

In Example 2, as the conductive particles 13, carbon particles PC-3 having a particle size of 30 μm manufactured by Nippon Carbon Co., Ltd.
020 is used as the heat-expandable microcapsule 14, and the expansion temperature manufactured by Matsumoto Yushi Co., Ltd. is 100 ° C. to 105 ° C. F.
Using 50D, 200 parts by weight of the conductive particles 13 and 20 parts by weight of the heat-expandable microcapsules 14 were dispersed in 100 parts by weight of the resin 12 so that the total thickness of the device was 200 μm.

In Example 3, silver particles G-15 manufactured by Dowa Mining Co., Ltd. having a particle diameter of 0.57 μm were used as the conductive particles 13, and the expansion temperature of Matsumoto Yushi Co., Ltd. was 100 as the thermally expandable microcapsules 14. C.-105.degree. C. F50D was used, 400 parts by weight of the conductive particles 13 and 20 parts by weight of the heat-expandable microcapsules 14 were dispersed in 100 parts by weight of the resin 12, and the total element thickness was 200 .mu.m.
And

In Example 4, silver particles G-15 manufactured by Dowa Mining Co., Ltd. having a particle size of 0.57 μm were used as the conductive particles 13, and the expansion temperature of Matsumoto Yushi Co., Ltd. was used as the thermally expandable microcapsules 14. Using F50D at ˜105 ° C., 400 parts by weight of the conductive particles 13 and 20 parts by weight of the heat-expandable microcapsules 14 are dispersed in 100 parts by weight of the resin 12, and the total thickness of the device is 300 μm.
And

In Example 5, silver particles G-15 made by Dowa Mining Co., Ltd. having a particle size of 0.57 μm are used as the conductive particles 13, and the expansion temperature of Matsumoto Yushi Co., Ltd. as the thermally expandable microcapsules 14 is 100 ° C. Using F50D at ˜105 ° C., 400 parts by weight of the conductive particles 13 and 20 parts by weight of the heat-expandable microcapsules 14 are dispersed in 100 parts by weight of the resin 12, and the total thickness of the device is 500 μm.
And

In Example 6, silver particles G-15 manufactured by Dowa Mining Co., Ltd. having a particle size of 0.57 μm are used as the conductive particles 13, and the expansion temperature of Matsumoto Yushi Co., Ltd. is 80 ° C. as the thermally expandable microcapsules 14. Using F30D at ˜85 ° C., 400 parts by weight of the conductive particles 13 and 20 parts by weight of the heat-expandable microcapsules 14 were dispersed in 100 parts by weight of the resin 12, and the total thickness of the device was 300 μm. .

In Example 7, silver particles G-15 manufactured by Dowa Mining Co., Ltd. having a particle size of 0.57 μm were used as the conductive particles 13, and the expansion temperature of Matsumoto Yushi Co., Ltd. was 140 ° C. as the thermally expandable microcapsules 14. Using F85D of ˜145 ° C., 400 parts by weight of the conductive particles 13 and 20 parts by weight of the thermally expandable microcapsules 14 are dispersed in 100 parts by weight of the resin 12, and the total element thickness is 300 μm.
And

In Example 8, silver particles Ag350 having a particle diameter of 40 μm manufactured by Dowa Mining Co., Ltd. were used as the conductive particles 13, and the expansion temperature of Matsumoto Yushi Co., Ltd. as the thermally expandable microcapsules 14 was 100 ° C. to 105 ° C. With F50D,
To 100 parts by weight of the resin 12, the conductive particles 13
400 parts by weight and this heat-expandable microcapsule 14
20 parts by weight were dispersed, and the total thickness of the device was set to 300 μm.

In Example 9, silver particles Ag350 having a particle diameter of 40 μm manufactured by Fukuda Metal Co., Ltd. were used as the conductive particles 13, and the expansion temperature of Matsumoto Yushi Co., Ltd., which was a thermal expansion microcapsule 14, was 100 ° C. to 105 ° C. With F50D,
To 100 parts by weight of the resin 12, the conductive particles 13
400 parts by weight and this heat-expandable microcapsule 14
Was dispersed in 100 parts by weight, and the total thickness of the device was set to 300 μm.

In Example 10, silver particles G-15 having a particle size of 0.57 μm manufactured by Dowa Mining Co., Ltd. were used as the conductive particles 13, and the expansion temperature of Matsumoto Yushi Co., Ltd. was used as the thermally expandable microcapsules 14. Using F50D at ˜105 ° C., 400 parts by weight of the conductive particles 13 and 10 parts by weight of the thermally expandable microcapsules 14 are dispersed in 100 parts by weight of the resin 12, and the total element thickness is 200 μm.
And

In Comparative Example 1, silver particles G-15 having a particle diameter of 0.57 μm manufactured by Dowa Mining Co., Ltd. were used as the conductive particles 13, and the expansion temperature of Matsumoto Yushi Co., Ltd. was 100 ° C. as the thermally expandable microcapsules 14. Using F50D at ˜105 ° C., 400 parts by weight of the conductive particles 13 and 5 parts by weight of the heat-expandable microcapsules 14 were dispersed in 100 parts by weight of the resin 12, and the total thickness of the device was 200 μm. .

[0028]

[Table 1] Here, Maker A is XC-72 manufactured by Cablack Co., Maker B is PC-3020 manufactured by Nippon Carbon Co., Maker C is G-15 manufactured by Dowa Mining Co., and Maker D is Ag manufactured by Fukuda Metal Foil & Powder Co.
350, Maker E is manufactured by Matsumoto Yushi Co., Ltd.

In the evaluation of Examples 1 to 10 and Comparative Example 1, each element cut into 1 cm square was left at each temperature shown in Table 1 for 2 minutes, and its resistance value was measured. In Examples 1 to 10, when the expansion temperature of the heat-expandable microcapsule 14 was reached, the volume of the heat-expandable microcapsule 14 suddenly increased and became a completely insulated state (10 ⁸ Ω or more). Further, all of the elements of Examples 1 to 10 were expanded by heat due to an overcurrent of 10 A and were in an insulating state.

In Comparative Example 1, even when the expansion temperature of the heat-expandable microcapsules 14 was reached, the insulating state was not established and 1
The resistance value was about 2.0Ω. The same was true when an overcurrent was passed. This is because in Comparative Example 1, the amount of the heat-expandable microcapsules 14 is relatively small, which is 5 parts by weight with respect to 400 parts by weight of the conductive particles 13.

As described above, according to the example of FIG. 1, when the overcurrent flows and the heat is generated, the volume of the heat-expandable microcapsule 14 rapidly expands, disconnects the conductive path, and operates as a fuse resistor and at the same time as the battery. In the thin example which can be mounted in a limited space such as the inside, a fuse resistor having a thickness of 200 μm to 500 μm can be obtained.

Another embodiment of the present invention will be described below with reference to FIG. In FIG. 2, reference numeral 3 indicates a circuit board made of a glass epoxy substrate having a thickness of 210 μm, for example.
For example, two electrode patterns 4a and 4b are provided parallel to each other with a distance of 2 μm therebetween. The electrode patterns 4a and 4b are copper foil having a thickness of 18 μm and plated with Ni having a thickness of 0.5 μm.

On the circuit board 3, a predetermined range, for example, 1.5 cm in the longitudinal direction of the electrode patterns 4a and 4b straddling the electrode patterns 4a and 4b.
The fuse resistance composition layer 1a is provided over 1.0 cm in a direction crossing over 4b.

The fuse resistance composition constituting the fuse resistance composition layer 1a is similar to the fuse resistance composition of FIG. 1 in that the thermoplastic polymer resin 12 contains metal particles 13 of nickel, silver or the like and a thermally expansive micro resin. The capsule 14 is dispersed.

The thermally expandable microcapsules 14 have hollow resin particles containing a low boiling point hydrocarbon and have a particle size of 10
It is a microsphere of μm to 30 μm. The thermoplastic resin 12 is preferably softened or rubber-like at the resin temperature of the heat-expandable microcapsules 14, and acrylic, polyester, urethane or the like can be used.

Next, Examples 11 to 15 and Comparative Example 2 of the fuse resistor as shown in FIG. 2 will be described.

In Example 11, polyester polymer UE3220 manufactured by Unitika Ltd. was used as the thermoplastic polymer resin 14, and silver particles G-15 (particle size 0.57 μm) manufactured by Dowa Mining Co., Ltd. were used as the conductive particles 13. Using toluene as the solvent, the resin 14 and the conductive particles 13 are mixed in a weight ratio of 1
It was blended at 0:90 and dispersed by three rolls. Into this, 100 parts by weight of the amount of resin therein was used as a thermally expandable microcapsule 14 as Microsphere F-50D (manufactured by Matsumoto Yushi Co., Ltd.). Micro balloon, expansion temperature 100 ℃ ~
(105 ° C.) in an amount of 1.0 part by weight and stirred with a dissolver for 10 minutes. This ink is spread over a predetermined range of the circuit board 3 across the electrode patterns 4a and 4b as shown in FIG. 2 using a bar coater. Applied and dried at 80 ° C. for 10 minutes to give a dry film thickness (thickness of the fuse resistance composition layer 1a) on the circuit board 3 of 48 μm.

In Example 12, the addition amount of the heat-expandable microcapsules 14 of Example 11 was blended in a ratio of 5.0 parts by weight with respect to 100 parts by weight of the resin. The dry film thickness on the substrate 3, that is, the thickness of the fuse resistance composition layer 1a was set to 51 μm.

In Example 13, the addition amount of the heat-expandable microcapsules 14 of Example 11 was blended in a ratio of 10.0 parts by weight with respect to 100 parts by weight of the resin, and otherwise the same as in Example 11, and the circuit was used. The dry film thickness on the substrate 3, that is, the thickness of the fuse resistance composition layer 1a was set to 52 μm.

Example 14 was similar to Example 12, and the dry film thickness on the circuit board 3, that is, the thickness of the fuse resistance composition layer 1a was set to 5 μm.

Example 15 was the same as Example 12, except that the dry film thickness on the circuit board 3, that is, the thickness of the fuse resistance composition layer 1a was set to 512 μm.

Further, in Comparative Example 2, the addition amount of the heat-expandable microcapsules 14 of Example 11 was blended at a ratio of 0.5 parts by weight with respect to 100 parts by weight of the resin, and otherwise the same as in Example 11, The dry film thickness on the circuit board 3, that is, the thickness of the fuse resistance composition layer 1a was set to 49 μm.

These Examples 11 to 15 and Comparative Example 2 were performed at 25 ° C., 50 ° C., 80 ° C., 100 ° C., 120 ° C., 140, respectively.
Leave for 2 minutes in a constant temperature bath adjusted to ℃ and 160 ℃, measure the resistance value between the electrode patterns 4a and 4b at that time, and also measure the time until the resistance value becomes 10 ⁸ Ω or more (Open) at 100 ℃. The measurement was performed and the results are shown in Table 2.

[0044]

[Table 2]

According to these results, in Examples 11 to 15, the fuse resistance composition layer 1a was lifted from the electrode patterns 4a and 4b at 100 ° C. and the conductive path was cut off (Ope).
n), the resistance value was about 40 KΩ in the comparative example, but the resistance value was not 10 ⁸ or more.

Further, the above-mentioned Examples 11 to 15 and Comparative Example 12
When an overcurrent of 10 A was applied to the
5 and Comparative Example 2 each generate heat, and Examples 11 to 15 each have a resistance value of 108 Ω or more (Op) at 100 ° C. as shown in Table 2.
en).

From the above, if the heat-expandable microcapsules 14 are blended in an amount of 1 part by weight or more with respect to 100 parts by weight of the resin 12, a fuse resistor will be satisfied, but if added in too large an amount, the initial resistance value will increase. Since it becomes high, it is preferable to mix it in an appropriate amount according to the target initial resistance.

The smaller the thickness of the fuse resistance composition layer 1a, the faster the breaking speed. However, even if this thickness increases, it takes time, but it does not mean that the fuse does not break. Although the fuse resistance composition layer 1a is applied by a bar coater in the above-mentioned embodiments, various methods such as screen printing can be used instead.

As described above, also in the example of FIG. 2, when the overcurrent flows and the heat is generated, the volume of the heat-expandable microcapsule abruptly expands and disconnects the conductive path, so that it functions as a fuse resistor and the inside of the battery. It is possible to obtain a thin fuse resistor that can be mounted in a limited space as shown in.

FIG. 4 shows another embodiment of the present invention. In FIG. 4 , 5 indicates a porous metal plate having a size of 2 mm or less, for example. The porous metal plate 5 does not need to be penetrated on both sides of the porous metal plate 5, and the metal foil electrodes 6a and 6b to be electrodes and the porous metal plate 5 can be sufficiently adhered to both sides or one side thereof. There should be a recess.

In this example, metal foil electrodes 6a and 6b are laminated and adhered on both surfaces of the porous metal plate 5 with an adhesive 7 interposed therebetween. In this case, a part of the metal foil electrodes 6a and 6b is brought into contact with the porous metal plate 5, and the adhesive 7 present in the recess of the porous metal plate 5 is used to form the porous metal plate 5 and the metal foil electrode 6a. , 6b are bonded together.

The metal foil electrodes 6a and 6b may be made of a metal or alloy such as aluminum, nickel or copper, or a good conductor of electricity such as alloys.

The adhesive 7 is a mixture of the thermally expandable microcapsules 14 in an adhesive containing an acrylic, epoxy, rubber or polyester resin 12 as a main component. As the thermally expandable microcapsules 14, those having a vinylidene chloride copolymer as a shell wall and containing a low boiling point hydrocarbon compound are commercially available.

The heat-expandable microcapsules 14 expand at a temperature of expansion, for example, 100 ° C., by encapsulating the low boiling point hydrocarbon compound and further softening the polymer resin forming the shell wall. Is.

The amount of the thermally expandable microcapsules 14 incorporated into the adhesive is preferably 0.1% by weight or more. This is because when the compounding amount of the heat-expandable microcapsules 14 in the adhesive is less than 0.1% by weight, the volume expansion of the adhesive 7 layer sufficient for disconnecting the conduction does not occur.

If the amount of the heat-expandable microcapsules 14 is too large, the adhesive component per unit volume decreases, and the metal foil electrodes 6a and 6b to be the electrodes are bonded to the porous metal plate 5. There is an inconvenience that causes defects.

Next, Examples 16 to 18 and Comparative Examples 3 and 4 of the fuse resistor as shown in FIG. 4 will be described.

In this Example 16, a tackifier (manufactured by Tonex Corp., Escorets 530) was added to a 30% toluene solution of a styrene / butadiene copolymer (TR1184, manufactured by Shell Chemical Co., Ltd.) so that the solid content ratio was 7: 3.
0) was added, and then heat-expandable microcapsules (F-50D manufactured by Matsumoto Yushi Co., Ltd.) having an expansion temperature of 105 ° C. were blended at a ratio of 0.1% by weight.

This was applied to an electrolytic nickel foil (65 μm thick manufactured by Fukuda Metal Foil & Powder Co., Ltd.) using a bar coater so that a wet film thickness was 300 μm, and dried in a hot air circulation oven at 80 ° C. for 10 minutes. (Dry film thickness at this time is 5
It was 0 μm. ), Which so to the configuration shown in FIG. 4, the porous metal plate 5 and ^{90 ℃, 4kgf / cm 2,} 6
It was thermocompression bonded under the condition of 0 seconds and punched into 1 cm square to obtain a 1.0 mm thick fuse resistor.

In Example 17, 10% by weight of heat-expandable microcapsules (F-85D, manufactured by Matsumoto Yushi Co., Ltd.) having an expansion temperature of 145 ° C. were added to a 30% toluene solution of saturated polyester (UE-3220, manufactured by Unitika Ltd.). Blended in a ratio, and electrolytic nickel foil (Fukuda Metal Foil & Powder Co., Ltd. 65 μm
Thickness) using a bar coater, wet film thickness 300 μm
And apply in a hot air circulation oven at 80 ° C.
In dried for 10 minutes (dry film thickness was 65 .mu.m.), Which porous metal plate so that the structure shown in FIG. 4 (Sumitomo Electric Co. Celmet (metal foam) # 7) 5
Then, thermocompression bonding was performed under the conditions of 90 ° C., 10 kgf / cm ² , and 60 seconds to obtain a fuse resistor having a thickness of 0.8 mm.

In Example 18, a phenoxy resin (Yp-50 manufactured by Tohto Kasei Co., Ltd.) in a 25% solution of a mixed solvent of toluene: butanol of 7: 3 was added to 40% by weight of thermally expandable microcapsules having an expansion temperature of 145 ° C. The mixture was mixed in a ratio, and this was applied to an electrolytic nickel foil (65 μm thickness manufactured by Fukuda Metal Foil & Powder Industry Co., Ltd.) using a bar coater so that a wet film thickness was 300 μm, and it was heated at 80 ° C. at 10 ° C. in a hot air circulation oven. minutes dried (dried film thickness was 50 [mu] m.), a porous metal plate 5 and 90 ° C. so that it to the configuration shown in FIG. 4, the heat under the conditions of 4 kgf / cm ^2, 60 seconds Crimping was performed to obtain a 1.0 mm thick fuse resistor.

In Comparative Example 3, the phenoxy resin solution of Example 18 was mixed with 50% by weight of heat-expandable microcapsules and thermocompression-bonded to the porous metal plate 5 by the method shown in Example 16. By the way, nickel foil metal foil electrode 6
No adhesive strength was obtained between a and 6b and the porous metal plate 5, peeling occurred in the punching process, and a fuse resistor could not be obtained.

The temperature-resistance characteristics and the current-resistance characteristics of Examples 16, 17 and 18 are shown in FIGS. 5 and 6, respectively.
That is, in the temperature-resistance characteristics of FIG. 5, in Example 16, the resistance was extremely small up to 105 ° C., but the thermally expandable microcapsules expanded at 105 ° C. and the metal foil electrode 6
Since the conductive paths between a and 6b and the porous metal plate 5 are cut off, the resistance between the electrodes 6a and 6b is infinite open (Ope).
n), and similarly in Examples 17 and 18, the resistance is infinite open (O) at the expansion temperature of 145 ° C.
pen).

In the current-resistance characteristics of FIG. 6, in Example 16, the resistance was extremely small up to 8.5 A, but when it reached 8.5 A, the heat-expandable microcapsules suddenly expanded due to heat generation by the current, and the metal Since the conductive paths between the foil electrodes 6a and 6b and the porous metal plate 5 are cut off, the resistance between the electrodes 6a and 6b becomes an infinite open (Open),
Similarly, in Examples 17 and 18, the heat-expandable microcapsule expands when the current is 9 A, and the resistance between the metal foil electrodes 6a and 6b is infinite open (Open).
Becomes

Therefore, the fuse resistors according to Examples 16, 17 and 18 have excellent characteristics as temperature fuses and current fuses, and can be made smaller and thinner.

[0066] attempt to explain still another embodiment of the present invention with reference to FIG. 3 below. In FIG. 3 , 8 has a thickness of 21
A circuit board consisting of a 0 μm glass epoxy board is shown.
Two electrode patterns 9a and 9b are formed on the circuit board 8 with a predetermined distance from each other, for example, 2 mm.

[0067] Also FIG. 3 A, as shown in B, and these two electrode patterns 9a and a predetermined width W0 example 10mm material layer 10 comprising a thermally expandable microcapsule 14 on the circuit board 8 between 9b Set up.

The paste for forming the material layer 10 is a polymer resin such as polyester UE3220 manufactured by Unitika Ltd. and thermally expandable microcapsules 14 such as Microballoon Microsphere F-50D (expansion temperature 100 ° C. to 105 ° C.) manufactured by Matsumoto Yushi Co., Ltd. For example, 20 wt% was added to this polymer resin, and toluene was used as a solvent, and the mixture was obtained by stirring for 10 minutes with a dissolver.

In this case, the polymer resin is preferably softened or has a rubber-like region at the expansion temperature of the heat-expandable microcapsules 14, and various resins such as acryl, polyester and urethane can be used.

A conductive paint layer 11 is formed so as to straddle the material layer 10 and electrically connect the electrode patterns 9a and 9b. An example of the conductive paint forming the conductive paint layer 11 is a polymer resin such as polyester U manufactured by Unitika Ltd.
Conductive particles (silver particles G-15 primary particle diameter 0.57 μm manufactured by Dowa Mining Co., Ltd.) were added to E3220 at a ratio of 900% by weight with respect to the resin, and toluene was used as a solvent to obtain a dispersion by three rolls. It was

In this case, carbon, nickel, silver or the like can be used as the conductive particles.

The material layer 10 and the conductive coating layer 11 containing the heat-expandable microcapsules can be formed by a method such as screen printing, but if an adhesive resin is used, it can be formed into a film and then attached.

The thickness d ₀ of the material layer 10 and the conductive coating layer 1
The relationship with the thickness d _{1 of 1} is preferably d ₀ / d ₁ ≧ 0.2, and if it is less than this, it becomes difficult for the thermally expandable microcapsules to penetrate through the conductive coating layer 11 and expand. . Further, the thickness d ₁ of the conductive paint layer 11 is 500 μm
When it exceeds, it becomes difficult for the thermally expandable microcapsules to break through the conductive paint layer 11 and expand.

[0074] The relationship between the width W ₁ of the width W ₀ and the conductive coating layer 11 of the material layer 10 containing a thermal expansion microcapsules is preferably W ₀ ≧ W _1, otherwise disadvantages portions not conduct cutting remains There is.

Since this example is constructed as described above, the temperature between the electrode patterns 9a and 9b is overheated or overcurrent so that the temperature of the thermally expandable microcapsules is, for example, 100 ° C.
4C and 4D, the thermally expandable microcapsules expand and pierce the conductive paint layer 11 to cut the conductive path, thereby electrically disconnecting the electrode patterns 9a and 9b. Acts as a fuse resistor. In this case, a thin fuse resistor can be used.

Here, Examples 1 to 15 are outside the present invention.
It The present invention is not limited to the above-described embodiments, and it goes without saying that various other configurations can be adopted without departing from the gist of the present invention.

[0077]

According to the present invention, when an overcurrent flows and heat is generated, the heat-expandable microcapsule expands, disconnects the conductive path, and operates as a fuse resistor, and in a limited space such as the inside of a battery. There is an advantage in having a thin fuse resistor that can be implemented.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a fuse resistor of the present invention.

FIG. 2 is a plan view showing another embodiment of the present invention.

FIG. 3 is a sectional view showing another embodiment of the present invention.

4A is a cross-sectional view showing another embodiment of the present invention, B is a plan view of FIG. 4A, C is a cross-sectional view for explaining the operation of this embodiment,
D is a plan view of FIG. 4C.

5 is a diagram for explaining the example of FIG. 3; FIG.

FIG. 6 is a diagram for explaining the example of FIG. 3;

[Explanation of symbols]

1 Fuse resistance composition layer 2a, 2b Metal electrode 3,8 circuit board 4a, 4b, 9a, 9b electrode pattern 5 Porous metal plate 6a, 6b Metal foil electrode 7 adhesive 10 Material layer containing thermally expandable microcapsules 11 Conductive paint layer 12 resin 13 Conductive particles 14 Thermally expandable microcapsules

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Motohide Takeshi 18 Satsuki-cho, Kanuma City, Tochigi Prefecture Sony Chemical Co., Ltd. Kanuma Plant (56) Reference JP-A-3-96255 (JP, A) JP-A-4 -245131 (JP, A) JP-A-53-88193 (JP, A) JP-A-60-19033 (JP, A) Actual opening Sho-58-71955 (JP, U) Actual opening Sho-62-23439 (JP, U) ) Shokai 57-170535 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01H 85/06 C08J 9/14 C08K 3/00 C08L 101/00

Claims (4)

(57) [Claims] 1. A metal foil electrode is laminated on both surfaces of a porous metal plate with an adhesive containing thermally expandable microcapsules.
A fuse resistor, wherein the adhesive is a thermally expansive adhesive.
Above the thermal expansion temperature of the black capsule, the thermal expansion
When the microcapsules expand, the porous metal plate and the gold
A fuse resistor characterized by cutting the conduction between metal foil electrodes . 2. A material layer containing heat-expandable microcapsules is provided between a plurality of electrode patterns formed on a substrate, and a conductive paint layer is formed so as to connect the plurality of electrode patterns across the material layer . In the formed fuse resistor
Therefore, the relationship between the material layer thickness d ₀ and the conductive coating layer thickness d ₁
Is d ₀ / d ₁ ≧ 0.2, and the temperature between the electrode patterns is
Above the thermal expansion temperature of the thermally expandable microcapsules
Then, the thermally expandable microcapsules expand and the
A fuse resistor characterized by breaking through a conductive paint layer . 3. This metal foil electrodes on both surfaces of the porous metal plate by laminating an adherend with an adhesive containing heat-expandable microcapsules, a portion of the metal foil electrode is in contact with the porous metal plate < A fuse resistor characterized by the following. 4. A material layer containing thermally expandable microcapsules is provided between a plurality of electrode patterns formed on a substrate, and a conductive paint layer is formed so as to connect the plurality of electrode patterns across the material layer. Fuse resistor characterized by having done.