JP6888262B2 - Wiring boards and electronics - Google Patents

Description

The present invention relates to wiring boards and electronic devices.

In recent years, wearable devices that can be worn on the human body and the like have been actively developed, and in connection with this, elastic wiring or wiring boards have been actively developed.

In this regard, the techniques described in Patent Document 1 or Patent Document 2 are known. Patent Document 1 includes, as an elastic wiring board, an elastic base material made of a first elastomer and an elastic wiring containing a conductive filler and a second elastomer, and the elastic base material and the elastic base material are expanded and contracted. A wiring board in which an elastic adhesion layer is formed between the sex wiring and the sex wiring is disclosed. Further, according to the description of Patent Document 1, it is shown that by adopting such a configuration, excellent reliability as an elastic wiring board is exhibited.

Further, Patent Document 2 includes a conductive layer having an elastomer, a conductive material filled in the elastomer, and a protective layer made of an elastomer arranged so as to cover the conductive layer. The conductive film is disclosed. According to the description of Patent Document 2, it is shown that the electric resistance of the conductive film is unlikely to increase even if it is stretched, and there is little possibility of breakage.

Japanese Unexamined Patent Publication No. 2014-151617 Japanese Unexamined Patent Publication No. 2010-153821

The techniques disclosed in Patent Document 1 and Patent Document 2 improve the durability of the wiring board as a whole by arranging the resin material having elasticity and conductivity so as to be in contact with other materials. It can be said that it is a thing.

However, when the wiring board is used as a wearable device, sufficient durability may not be obtained in some cases. From such a technical background, it has been required to improve the durability of the wiring board in the usage environment of the wearable device. As a result of diligent studies by the inventor, it became clear that sweating of the human body and the like affect the durability of the wiring board.

The present invention has been made in view of the above circumstances, and provides an elastic substrate having excellent durability.

As a result of further diligent studies by the present inventors, it has been found that when a specific immersion test is performed on a substrate, particularly high durability can be exhibited as a wiring board by satisfying a certain condition of weight change behavior.

According to the present invention
With an elastic substrate,
A wiring board in which elastic and conductive wiring is laminated.
The weight of the substrate before the test of immersing in the acidic artificial sweat solution specified in JIS L0848 at 25 ° C. for 7 days was set to W _0, and the weight of the substrate after the test was set to Wa, and the test was performed. Then, when the weight of the substrate after further drying at 40 ° C. for 4 hours is Wb, the _{value represented by (Wa-Wb) / W 0} × 100 [%] is 3.0%. Ri der below,
The hardness of the substrate at 25 ° C. measured by the type A durometer specified in JIS K6253 before the test is Ha, and the hardness at 25 ° C. measured by the type A durometer specified in JIS K6253 after the test. When Hb is used, (Hb-Ha) / Ha × 100 [%] is -10% or more.
A notched crescent test piece is prepared from the substrate, the test piece is subjected to the same test as the test, and the tear strength of the test piece before the test measured by the method of JIS K6252 is set to TRa. , (TRb-TRA) / TRa × 100 [%] is −40% or more, where TRb is the tear strength after the test measured by the method of JIS K6252.
When the tensile strength of the substrate before the test measured by the method of JIS K7161 is TBa and the tensile strength after the test measured by the method of JIS K7161 is TBb, (TBb-TBa). ) / TBa × 100 [%] is -50% or more and 5% or less.
A wiring board is provided.

According to the present invention
An electronic device including the above wiring board is provided.

According to the present invention, it is possible to provide an elastic substrate having excellent durability.

It is sectional drawing which shows the structural example of the electronic device which concerns on embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Further, in the present specification, "~" means "greater than or equal to" to "less than or equal to" unless otherwise specified.

The wiring board according to the embodiment is a wiring board in which a stretchable board and a stretchable and conductive wiring board are laminated. Then, the weight of the substrate before the test of immersing in the acidic artificial sweat solution defined by JIS L0848 at 25 ° C. for 7 days was set to W _0, and the weight of the substrate after the test was set to Wa, and the test was performed. After that, when the weight of the substrate after further drying under the condition of 40 ° C. for 4 hours is Wb, the _{value represented by (Wa-Wb) / W 0} × 100 [%] is 3.0% or less. .. This will be described in detail below.

In the wiring board according to this embodiment, the board contains a first elastomer. The wiring also contains a second elastomer. Therefore, the substrate and the wiring each have elasticity, and this wiring board is suitably used as a flexible device, particularly a wearable device. The first elastomer and the second elastomer may be the same elastomer or different elastomers.

Substrate according to the present embodiment, when performing the test of immersing for 7 days at 25 ° C. acidified artificial sweat liquid defined by JIS L0848, the ratio of the water content of the test piece after the test to the weight W ₀ before the test WRd is in the range of 0% or more and 3.0% or less. That is, the substrate of the present embodiment satisfies the above conditions when an immersion test in an acidic artificial sweat solution under specific conditions (hereinafter, also simply referred to as "test") is performed. By satisfying specific conditions when the immersion test is performed in this way, the present inventors are sufficient when a device (wearable device) in which a wiring board using this board is mounted on a human body is used as an application. It was found to have high durability.

In the above immersion test, the mixture is immersed in an acidic artificial sweat solution defined by JIS L0848 at 25 ° C. for 7 days. Specifically, the immersion test can be performed as follows, for example. Prepare a test piece of the substrate and measure _{the weight W 0 before the test.} The dimensions of the test piece are, for example, 20 mm × 50 mm and a thickness of 1 mm. The dimensions of the test piece may differ from the above depending on the size of the substrate. Then, the entire test piece is immersed in an acidic artificial sweat solution defined by JIS L0848 in a closed container. The temperature of the acidic artificial sweat solution is set to 25 ° C., and the mixture is allowed to stand for 7 days. After standing, the test piece is taken out from the acidic artificial sweat solution, the water on the surface is removed, and the weight Wa after the test is measured. Further, the test piece is dried at 40 ° C. for 4 hours, and the weight Wb after drying is measured.

Here, the water content of the test piece after the test is represented by Wa-Wb. Then, by _{setting the ratio WRd [%] of the water content of the test piece after the test to the weight W 0} before the test within the range of 0% or more and 3.0% or less, the substrate is used and the durability is high. You can get a wiring board. WRd is obtained by the relationship of WRd = (Wa-Wb) / W ₀ × 100 [%].

When the inventors diligently investigated the failure of the wiring board in the wearable device, it became clear that the durability of the wiring depends not only on the material and characteristics of the wiring but also on the material and characteristics of the substrate. Further, by setting the WRd to 3.0% or less, even when the wiring board is used for a wearable device, the wiring is less likely to be cut or the wiring is cracked, and a highly durable wiring board can be obtained. I found that. The reason for this is not clear, but it can be inferred that the decrease in the strength of the wiring caused by the moisture infiltrating into the substrate, permeating and contacting the wiring is suppressed. In wearable devices, it is presumed that the repeated high-humidity state due to the release of water vapor and sweating from the user's skin and the low-humidity state where the water evaporates is one of the causes of damage to the wiring. .. In the present embodiment, by using a substrate having a WRd of 3.0% or less when the above immersion test is performed, it is possible to improve the durability as a wiring board having a composite structure of the substrate and wiring. ..

When the immersion test is performed on the substrate according to the present embodiment, the WRd is 3.0% or less, more preferably 2.0% or less, and further preferably 0.5% or less. Then, the durability of the wiring board can be further improved.

Further, when the hardness of the substrate according to the present embodiment is Ha before the above test and Hb is after the test, (Hb-Ha) / Ha × 100 [%] is -10% or more. It is preferably -4% or more, more preferably -1% or more. Then, the durability of the wiring board can be further improved. Further, (Hb-Ha) / Ha × 100 [%] is, for example, 10% or less. The hardness Ha before the test and the hardness Hb after the test can be measured at 25 ° C. by the type A durometer specified in JIS K6253, respectively.

The hardness Hb of the substrate after the immersion test is, for example, preferably 27 or more, and more preferably 29 or more. Then, the durability of the wiring board can be further improved.

When the tear strength of the test piece prepared from the substrate according to the present embodiment before the test is TRa and the tear strength after the test is TRb, (TRb-TRA) / TRa × 100 [%] is It is preferably -40% or more, and more preferably -30% or more. Then, the durability of the wiring board can be further improved. Further, (TRb-TRA) / TRa × 100 [%] is, for example, 30% or less. The tear strength TRa and the tear strength TRb can be measured as follows. That is, a crescent-shaped test piece with a notch is prepared from the substrate, the test piece is subjected to the same test as the above test, the tear strength of the test piece before the test is TRa, and the tear strength after the test is set. Let TRb be. The tear strength TRa before the test and the tear strength TRb after the test can be measured according to the method of JIS K6252, respectively.

The tear strength TRb of the substrate after the immersion test is preferably, for example, 6.5 N / mm or more, and more preferably 30 N / mm or more. Then, the durability of the wiring board can be further improved.

When the tensile strength of the substrate of the present embodiment before the above test is TBa and the tensile strength after the test is TBb, (TBb-TBa) / TBa × 100 [%] is −50% or more. It is preferably -30% or more, and more preferably -25% or more. Then, the durability of the wiring board can be further improved. Further, (TBb-TBa) / TBa × 100 [%] is, for example, 5% or less. The tensile strength TBa before the test and the tensile strength TBb after the test can be measured according to the method of JIS K7161 respectively.

The tensile strength TBb of the substrate after the immersion test is preferably 5 ^{N / mm 2 or more, for example.} Then, the durability of the wiring board can be further improved.

In the wiring board of the present embodiment, the ratio R _re / R _{ini of the resistor R ini} [Ω] and the resistor R _re [Ω] described below is not particularly limited, but can be, for example, 5 or less, preferably 5. It can be 3 or less, more preferably 2 or less. Here, the resistance R _ini [Ω] is the resistance of the wiring in the non-stretchable state before the acidic artificial sweat liquid is brought into contact with the resistance. Further, the resistor R _re [Ω] is a non-woven fabric impregnated with an acidic artificial sweat liquid that is brought into contact with only the surface opposite to the surface on which the wiring is formed, and left to stand for 7 days as it is, and then the wiring is in a non-stretchable state. It is resistance.

In the wiring board, the width, thickness, shape, etc. of the wiring are not particularly limited, but the width of the wiring is, for example, 0.2 mm or more and 1.0 mm or less. The thickness of the wiring is, for example, 10 μm or more and 500 μm or less.

The manufacturing method of the wiring board according to this embodiment will be described below. However, the following method shows an example of a method for manufacturing a wiring board having a substrate having a WRd of 0% or more and 3.0% or less when the above immersion test is performed. The manufacturing method is not particularly limited as long as it is a wiring board having a substrate having a WRd of 0% or more and 3.0% or less when the above immersion test is performed.

The substrate according to this embodiment can be produced by using a resin composition for forming a substrate containing the first elastomer. Further, the wiring according to the present embodiment can be composed of a conductive resin composition containing a second elastomer. Hereinafter, each resin composition will be described.

<< Resin composition for substrate formation >>
As the first elastomer, for example, silicone rubber, fluororubber, nitrile rubber, acrylic rubber, styrene rubber, chloroprene rubber, ethylene propylene rubber, urethane rubber and the like can be used. Among these, the first elastomer contained in the substrate is preferably one or more materials selected from the group consisting of silicone rubber, urethane rubber, fluororubber, and acrylic rubber. When the first elastomer contains silicone rubber, a wiring board having excellent elasticity, heat resistance, chemical stability, and biocompatibility can be obtained. Further, when the first elastomer contains urethane rubber, a wiring board having excellent elasticity, mechanical strength, and abrasion resistance can be realized.

<Silicone rubber-based curable composition>
In the following, first, an example in which the substrate according to the present embodiment is composed of a silicone rubber-based curable composition containing silicone rubber as the first elastomer will be described. That is, a silicone rubber-based curable composition can be used as a resin composition for forming a substrate.

(Elastomer (A))
The silicone rubber-based curable composition contains silicone rubber as the elastomer (A).

As the silicone rubber, for example, one having a siloxane structure in the molecule is used.
In the present embodiment, among such silicone rubbers, a silicone rubber obtained by cross-linking a vinyl group-containing linear organopolysiloxane (A-1) with an organohydrogenpolysiloxane (A-2) is preferably used. Be done.

[Vinyl group-containing linear organopolysiloxane (A-1)]
The vinyl group-containing linear organopolysiloxane (A-1) has a linear structure and contains a vinyl group, and the vinyl group serves as a cross-linking point at the time of curing.

The content of the vinyl group of this vinyl group-containing linear organopolysiloxane (A-1) is not particularly limited, but has two or more vinyl groups in the molecule and the content of the vinyl group is 15 mol. It is preferably less than or equal to%, and more preferably 0.01 to 12 mol%. As a result, the amount of vinyl groups in the vinyl group-containing linear organopolysiloxane (A-1) is optimized, and a network with each component can be reliably formed.

In the present specification, the vinyl group content is the molar amount of the vinyl group-containing siloxane unit when all the units constituting the vinyl group-containing linear organopolysiloxane (A-1) are 100 mol%. %. However, the calculation is performed assuming that there is one vinyl group for each vinyl group-containing siloxane unit.

The degree of polymerization of the vinyl group-containing linear organopolysiloxane (A-1) is not particularly limited, but is preferably in the range of 1000 to 10000, more preferably 2000 to 5000. The degree of polymerization can be determined, for example, as the polystyrene-equivalent number average degree of polymerization (or number average molecular weight) in GPC (gel permeation chromatography) using chloroform as a developing solvent.

Further, the specific gravity of the vinyl group-containing linear organopolysiloxane (A-1) is not particularly limited, but is preferably in the range of about 0.9 to 1.1.

By using a vinyl group-containing linear organopolysiloxane (A-1) having a degree of polymerization and specific gravity within the above range, the silicone rubber-based curable composition obtained has heat resistance and flame retardancy. It is possible to improve the properties, chemical stability, and the like.

The vinyl group-containing linear organopolysiloxane (A-1) preferably has a structure represented by the following formula (1).

In formula (1), R ¹ is a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, an alkenyl group, an aryl group, or a hydrocarbon group in which these are combined. Examples of the alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group, a propyl group and the like, and among them, a methyl group is preferable. Examples of the alkenyl group having 1 to 10 carbon atoms include a vinyl group, an allyl group, a butenyl group and the like, and among them, a vinyl group is preferable. Examples of the aryl group having 1 to 10 carbon atoms include a phenyl group and the like.

Further, R ² is a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, an alkenyl group, an aryl group, or a hydrocarbon group in which these are combined. Examples of the alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group, a propyl group and the like, and among them, a methyl group is preferable. Examples of the alkenyl group having 1 to 10 carbon atoms include a vinyl group, an allyl group, and a butenyl group. Examples of the aryl group having 1 to 10 carbon atoms include a phenyl group.

Further, R ³ is a substituted or unsubstituted alkyl group having 1 to 8 carbon atoms, an aryl group, or a hydrocarbon group in which these are combined. Examples of the alkyl group having 1 to 8 carbon atoms include a methyl group, an ethyl group, a propyl group and the like, and among them, a methyl group is preferable. Examples of the aryl group having 1 to 8 carbon atoms include a phenyl group.

^{Further, examples of the substituent of R 1} and R ^{2 in} the formula (1) include a methyl group, a vinyl group and the like, and examples ^{of the substituent of R 3} include a methyl group and the like.

In the formula (1), a plurality of R ¹ is independent from each other, may be different from each other, it may be the same. The same applies to ^{R 2} and R ^3.

Further, m and n are the number of repeating units constituting the vinyl group-containing linear organopolysiloxane (A-1) represented by the formula (1), m is an integer of 0 to 2000, and n is 1000. It is an integer of 10000. m is preferably 0 to 1000, and n is preferably 2000 to 5000.

Further, as a more specific structure of the vinyl group-containing linear organopolysiloxane (A-1) represented by the formula (1), for example, the one represented by the following formula (1-1) can be mentioned.

In formula (1-1), R ¹ and R ² are each independently a methyl group or a vinyl group, and at least one of them is a vinyl group.

Further, the vinyl group-containing linear organopolysiloxane (A-1) as described above has two or more vinyl groups in the molecule and has a vinyl group content of 0.4 mol% or less. A first vinyl group-containing linear organopolysiloxane (A-1 (a)) and a second vinyl group-containing linear organopolysiloxane (A) having a vinyl group content of 0.5 to 15 mol%. It preferably contains -1 (b)). As the elastomer (A), a first vinyl group-containing linear organopolysiloxane (A-1 (a)) having a general vinyl group content and a second vinyl group-containing direct link having a high vinyl group content. By combining with a chain organopolysiloxane (A-1 (b)), the vinyl groups can be unevenly distributed, and the cross-linking density can be more effectively formed in the cross-linking network of the silicone rubber. it can. As a result, the tear strength of the silicone rubber can be increased more effectively. Further, as a result, the durability of the silicone rubber-based curable composition as a cured product can be dramatically improved.

Specifically, as the vinyl group-containing linear organopolysiloxane (A-1), for example, in the above formula (1-1), the ^{unit in which R 1} is a vinyl group and / or R ² is a vinyl group. has two or more in the unit molecule and a first vinyl-containing linear organopolysiloxane containing 0.4 mole% or less (a-1 (a)) , the unit R ¹ is a vinyl group and It is preferable to use a second vinyl group-containing linear organopolysiloxane (A-1 (b)) containing 0.5 to 15 mol% of the unit in which ^{R 2 is a vinyl group.}

Further, the first vinyl group-containing linear organopolysiloxane (A-1 (a)) preferably has a vinyl group content of 0.01 to 0.2 mol%. The vinyl group-containing linear organopolysiloxane (A-1 (b)) preferably has a vinyl group content of 0.8 to 12 mol%.

Further, when the first vinyl group-containing linear organopolysiloxane (A-1 (a)) and the second vinyl group-containing linear organopolysiloxane (A-1 (b)) are blended in combination. , (A-1 (a)) and (A-1 (b)) are not particularly limited, but usually (A-1 (a)) :( A-1 (b)) is 50 in terms of mass ratio. : 50 to 95: 5, more preferably 80:20 to 90:10.

As the first and second vinyl group-containing linear organopolysiloxanes (A-1 (a)) and (A-1 (b)), only one type may be used, or two or more types may be used. May be used in combination.

[Organohydrogenpolysiloxane (A-2)]
Organohydrogenpolysiloxane (A-2) is a linear organohydrogenpolysiloxane (A-2 (a)) having a linear structure and a branched organohydrogenpolysiloxane (A-2 (A-2)) having a branched structure. It is classified into b)), and in this embodiment, only the linear organohydrogenpolysiloxane (A-2 (a)) may be used, or only the branched organohydrogenpolysiloxane (A-2 (b)) may be used. Alternatively, both of these linear organohydrogenpolysiloxanes (A-2 (a)) and branched organohydrogenpolysiloxanes (A-2 (b)) may be contained.

The linear organohydrogenpolysiloxane (A-2 (a)) has a linear structure and a structure in which hydrogen is directly bonded to Si (≡Si—H), and is a vinyl group-containing linear structure. In addition to the vinyl group of the organopolysiloxane (A-1), it is a polymer that acts on the reactive groups of the components contained in the silicone rubber-based curable composition to crosslink these components.

The molecular weight of the linear organohydrogenpolysiloxane (A-2 (a)) is not particularly limited, but the weight average molecular weight is preferably 20000 or less, and more preferably 1000 or more and 10000 or less.

The weight average molecular weight of the linear organohydrogenpolysiloxane (A-2 (a)) can be measured, for example, by polystyrene conversion in GPC (gel permeation chromatography) using chloroform as a developing solvent.

Further, the linear organohydrogenpolysiloxane (A-2 (a)) preferably does not have a vinyl group. This makes it possible to accurately prevent the cross-linking reaction from proceeding in the molecule of the linear organohydrogenpolysiloxane (A-2 (a)).

As the linear organohydrogenpolysiloxane (A-2 (a)) as described above, for example, one having a structure represented by the following formula (2) is preferably used.

In the formula (2), R ⁴ is a hydrocarbon group or a hydride group, in combination a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, an alkenyl group, an aryl group, these. Examples of the alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group, a propyl group and the like, and among them, a methyl group is preferable. Examples of the alkenyl group having 1 to 10 carbon atoms include a vinyl group, an allyl group, a butenyl group and the like. Examples of the aryl group having 1 to 10 carbon atoms include a phenyl group.

Also, R ⁵ is a hydrocarbon group or a hydride group, in combination a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, an alkenyl group, an aryl group, these. Examples of the alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group and a propyl group, and among them, a methyl group is preferable. Examples of the alkenyl group having 1 to 10 carbon atoms include a vinyl group, an allyl group, a butenyl group and the like. Examples of the aryl group having 1 to 10 carbon atoms include a phenyl group.

In the formula (2), a plurality of R ⁴ are independent from each other, may be different from each other, it may be the same. The same is true for R ^5. However, of the plurality of R ⁴ and R ⁵ , at least two or more are hydride groups.

Further, R ⁶ is a substituted or unsubstituted alkyl group having 1 to 8 carbon atoms, an aryl group, or a hydrocarbon group in which these are combined. Examples of the alkyl group having 1 to 8 carbon atoms include a methyl group, an ethyl group, a propyl group and the like, and among them, a methyl group is preferable. Examples of the aryl group having 1 to 8 carbon atoms include a phenyl group. A plurality of R ⁶ are independent from each other, may be different from each other, it may be the same.

^{Examples of the substituent of R 4} , R ⁵ , and R ^{6 in} the formula (2) include a methyl group and a vinyl group, and a methyl group is preferable from the viewpoint of preventing an intramolecular cross-linking reaction.

Further, m and n are the number of repeating units constituting the linear organohydrogenpolysiloxane (A-2 (a)) represented by the formula (2), and m is an integer of 2 to 150 and n. Is an integer of 2 to 150. Preferably, m is an integer of 2 to 100 and n is an integer of 2 to 100.

The linear organohydrogenpolysiloxane (A-2 (a)) may be used alone or in combination of two or more.

Since the branched organohydrogenpolysiloxane (A-2 (b)) has a branched structure, it forms a region having a high crosslink density, and is a component that greatly contributes to the formation of a sparsely packed structure with a crosslink density in the silicone rubber system. is there. Further, like the linear organohydrogenpolysiloxane (A-2 (a)), it has a structure (≡Si—H) in which hydrogen is directly bonded to Si, and is a vinyl group-containing linear organopolysiloxane (A). In addition to the vinyl group of -1), it is a polymer that acts on the reactive groups of each component blended in the silicone rubber-based curable composition and crosslinks these components.

The specific gravity of the branched organohydrogenpolysiloxane (A-2 (b)) is in the range of 0.9 to 0.95.

Further, the branched organohydrogenpolysiloxane (A-2 (b)) usually preferably has no vinyl group. This makes it possible to accurately prevent the cross-linking reaction from proceeding in the molecule of the branched organohydrogenpolysiloxane (A-2 (b)).

Further, as the branched organohydrogenpolysiloxane (A-2 (b)), those represented by the following average composition formula (c) are preferable.

Average composition formula (c)
^{_{(H a (R 7) 3}} -a SiO 1/2) m (SiO 4/2) n
(In the formula (c), ^{R 7} is a monovalent organic group, a is 1 to 3 in the range of integers, m is ^{_{H a (R 7) 3-}} a number of _{SiO 1/2} units, n represents SiO _{4 /} It is a number of _{2 units).}

In formula (c), R ⁷ is a monovalent organic group, preferably a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, an aryl group, or a hydrocarbon group in combination thereof. Examples of the alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group, a propyl group and the like, and among them, a methyl group is preferable. Examples of the aryl group having 1 to 10 carbon atoms include a phenyl group.

In the formula (c), a is the number of hydride groups (hydrogen atoms directly bonded to Si), is an integer in the range of 1 to 3, and is preferably 1.

Further, in the equation (c), m is ^{_{H a (R 7) 3-}} a number of _{SiO 1/2} units, n is the number of _{SiO 4/2} units.

The branched organohydrogenpolysiloxane (A-2 (b)) has a branched structure. The linear organohydrogenpolysiloxane (A-2 (a)) and the branched organohydrogenpolysiloxane (A-2 (b)) differ in that their structures are linear or branched, and Si. The number of alkyl groups R (R / Si) bonded to Si when the number of is 1 is 1.8 to 2.1 for the linear organohydrogenpolysiloxane (A-2 (a)), which is branched. In the form of organohydrogenpolysiloxane (A-2 (b)), the range is 0.8 to 1.7.

Since the branched organohydrogenpolysiloxane (A-2 (b)) has a branched structure, for example, a residue when heated to 1000 ° C. at a heating rate of 10 ° C./min under a nitrogen atmosphere. The amount will be 5% or more. On the other hand, since the linear organohydrogenpolysiloxane (A-2 (a)) is linear, the amount of residue after heating under the above conditions is almost zero.

Further, specific examples of the branched organohydrogenpolysiloxane (A-2 (b)) include those having a structure represented by the following formula (3).

In formula (3), R ⁷ is a substituted or unsubstituted alkyl group having 1 to 8 carbon atoms, an aryl group, or a hydrocarbon group combining these, or a hydrogen atom. Examples of the alkyl group having 1 to 8 carbon atoms include a methyl group, an ethyl group, a propyl group and the like, and among them, a methyl group is preferable. Examples of the aryl group having 1 to 8 carbon atoms include a phenyl group. Examples of the substituent of R ⁷ include a methyl group and the like.

In the equation (3), the plurality of R ^7s are independent of each other and may be different from each other or may be the same.

Further, in the equation (3), "-O-Si≡" indicates that Si has a branched structure that spreads three-dimensionally.

The branched organohydrogenpolysiloxane (A-2 (b)) may be used alone or in combination of two or more.

In the linear organohydrogenpolysiloxane (A-2 (a)) and the branched organohydrogenpolysiloxane (A-2 (b)), the amount of hydrogen atoms (hydride groups) directly bonded to Si is , Each is not particularly limited. However, in the present embodiment, for 1 mol of the vinyl group in the vinyl group-containing linear organopolysiloxane (A-1), the linear organohydrogenpolysiloxane (A-2 (a)) and the branched organo are branched. The total amount of hydride groups of the hydrogen polysiloxane (A-2 (b)) is preferably 0.5 to 5 mol, more preferably 1 to 3.5 mol. As a result, the linear organohydrogenpolysiloxane (A-2 (a)) and the branched organohydrogenpolysiloxane (A-2 (b)) and the vinyl group-containing linear organopolysiloxane (A-1) ), A bridged network can be reliably formed.

Further, the linear organohydrogenpolysiloxane (A-2 (a)) and the branched organohydrogenpolysiloxane (A-2 (b)) are usually composed of a linear organohydrogenpolysiloxane (A-). 2 (a)) is contained as a main agent, and the branched organohydrogenpolysiloxane (A-2 (b)) is added when the silicone rubber is formed with a region having a higher crosslink density, as described above. .. Therefore, when the linear organohydrogenpolysiloxane (A-2 (a)) and the branched organohydrogenpolysiloxane (A-2 (b)) are combined and blended, (A-2 (a)). The ratio of (A-2 (b)) to (A-2 (b)) is preferably (A-2 (a)) :( A-2 (b)) by weight, preferably 1: 0.1 to 1: 1. It is set to 1: 0.2 to 1: 0.5.

The content of the organohydrogenpolysiloxane (A-2) is 100, specifically, the total amount of the vinyl group-containing linear organopolysiloxane (A-1), the silica particles (B), and the silane coupling agent (C). For example, it is preferably contained in a proportion of 0.1 parts by weight or more and 20 parts by weight or less, and more preferably 0.2 parts by weight or more and 15 parts by weight or less with respect to parts by weight. When the content of the organohydrogenpolysiloxane (A-2) is within the above range, a more effective curing reaction may be possible.

In the present embodiment, the content of the elastomer (A) in the silicone rubber-based curable composition is preferably 30% by mass or more, preferably 50% by mass, based on the total solid content of the silicone rubber-based curable composition. It is more preferably% or more, and even more preferably 55% by mass or more. The content of the elastomer (A) in the silicone rubber-based curable composition is preferably 95% by mass or less, preferably 93% by mass or less, based on the total solid content of the silicone rubber-based curable composition. It is more preferable that the content is 90% by mass or less.
By setting the content of the elastomer (A) to the above lower limit value or more, the cured product of the silicone rubber-based curable composition can have appropriate flexibility. Further, by setting the content of the elastomer (A) to the above upper limit value or less, the mechanical strength of the cured product can be improved.
In the present specification, the “solid content” refers to the entire component from which volatile components such as water and organic solvent have been removed, and for example, a component that does not volatilize even if it is liquid at room temperature. , Assuming that it is a solid content. Hereinafter, the same applies to each component.

(Silica particles (B))
The silicone rubber-based curable composition of the present embodiment may contain silica particles (B), if necessary. By including the silica particles (B), it is possible to improve the hardness and mechanical strength of the cured product formed from the silicone rubber-based curable composition.

The silica particles (B) is, for example, preferably the specific surface area by BET method is 50 to 400 m ² / g, more preferably 100 to 400 m ² / g. The average primary particle size is preferably 1 to 100 nm, more preferably 5 to 20 nm.

By using the silica particles (B) within the range of the specific surface area and the average primary particle size, the above-mentioned function as the silica particles (B) can be remarkably exhibited.
The particle size of the silica particles (B) is determined by, for example, observing the silicone rubber-based curable composition or the cured product with a transmission electron microscope or the like, performing image analysis, and arbitrarily selecting 200 silica particles. It can be defined as an average value.

The silica particles (B) are not particularly limited, but for example, fumed silica, calcined silica, precipitated silica and the like can be used.
As the silica particles (B), only one type may be used alone, or two or more types may be used in combination.

In the present embodiment, the content of the silica particles (B) in the silicone rubber-based curable composition is determined when the silicone rubber-based curable composition contains a vinyl group-containing linear organopolysiloxane (A-1). It is preferably 5 parts by weight or more, more preferably 10 parts by weight or more, and 20 parts by weight or more, based on 100 parts by weight of the vinyl group-containing linear organopolysiloxane (A-1). More preferred. The content of the silica particles (B) in the silicone rubber-based curable composition is, when the silicone rubber-based curable composition contains a vinyl group-containing linear organopolysiloxane (A-1), contains a vinyl group. It is preferably 100 parts by weight or less, more preferably 80 parts by weight or less, and further preferably 70 parts by weight or less with respect to 100 parts by weight of the linear organopolysiloxane (A-1).
By setting the content of the silica particles (B) to be equal to or greater than the above lower limit value and equal to or less than the upper limit value, the cured product of the silicone rubber-based curable composition can have an appropriate mechanical strength.

(Silane Coupling Agent (C))
The silicone rubber-based curable composition of the present embodiment may contain a silane coupling agent (C). This silane coupling agent (C) has a hydrolyzable group, and this hydrolyzable group is hydrolyzed by water to become a hydroxyl group, and this hydroxyl group undergoes a dehydration condensation reaction with the hydroxyl group on the surface of the silica particles (B). By doing so, the surface of the silica particles (B) can be modified.
In addition, even when the silica particles (B) are not present, the effect of improving the adhesion between the wiring and the substrate can be exhibited.

Further, as this silane coupling agent (C), one having a hydrophobic group can be used. As a result, this hydrophobic group is imparted to the surface of the silica particles (B), so that the cohesive force of the silica particles (B) is reduced in the silicone rubber-based curable composition, and as a result, in the composition. The dispersibility of silica particles is improved. As a result, the mechanical strength of the cured product of the silicone rubber-based curable composition is further improved.

Further, the silane coupling agent (C) preferably has a vinyl group. As a result, when silica particles (B) are used, vinyl groups are introduced on the surface thereof.
As a result, for example, when the elastomer (A) contains a vinyl group-containing linear organopolysiloxane (A-1) and an organohydrogenpolysiloxane (A-2), the following effects are obtained. ..
That is, when the silicone rubber-based curable composition is cured, that is, the vinyl group contained in the vinyl group-containing linear organopolysiloxane (A-1) and the hydride group contained in the organohydrogenpolysiloxane (A-2). When the and are hydrosilylated to form a network (crosslinked structure) by these, the vinyl group of the silica particles (B) is also hydrosilylated with the hydride group of the organohydrogenpolysiloxane (A-2). Silica particles (B) are also incorporated into the network because they are involved in the silicate reaction. As a result, it is possible to increase the hardness and the modulus of the cured product to be formed.

Examples of such a silane coupling agent (C) include those represented by the following formula (4).

Y _n- Si- (X) _4-n ... (4)
In the above equation (4), n represents an integer of 1 to 3. Y represents any functional group having a hydrophobic group, a hydrophilic group or a vinyl group, and when n is 1, it is a hydrophobic group, and when n is 2 or 3, at least one of them is. It is a hydrophobic group. X represents a hydrolyzable group.

The hydrophobic group is an alkyl group having 1 to 6 carbon atoms, an aryl group, or a hydrocarbon group in which these are combined, and examples thereof include a methyl group, an ethyl group, a propyl group, a phenyl group, and the like. Methyl groups are preferred.

Examples of the hydrophilic group include a hydroxyl group, a sulfonic acid group, a carboxyl group, a carbonyl group and the like, and among them, a hydroxyl group is particularly preferable. The hydrophilic group may be contained as a functional group, but is preferably not contained from the viewpoint of imparting hydrophobicity to the silane coupling agent (C).

Further, examples of the hydrolyzable group include an alkoxy group such as a methoxy group and an ethoxy group, a chloro group or a silazane group. Those having a silazane group as a hydrolyzable group have _{two structures of (Y n −} Si−) in the above formula (4) due to their structural characteristics.

Specific examples of the silane coupling agent (C) represented by the above formula (4) include, for example, methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, and methyltri as those having a hydrophobic group as a functional group. Ekoxysilanes such as ethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, decyltrimethoxysilane; methyltrichlorosilane , Dimethyldichlorosilane, trimethylchlorosilane, chlorosilanes such as phenyltrichlorosilane; hexamethyldisilazane, examples of which have a vinyl group as a functional group include methacryloxypropyltriethoxysilane, methacryloxypropyltrimethoxysilane, methacryloxy. Ekoxysilanes such as propylmethyldiethoxysilane, methacryloxypropylmethyldimethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, vinylmethyldimethoxysilane; chlorosilanes such as vinyltrichlorosilane, vinylmethyldichlorosilane; divinyltetramethyldi Examples thereof include silazane and 1,3-divinyldisilazane. Among them, in consideration of the above description, hexamethyldisilazane has a hydrophobic group, and divinyltetramethyldisilazane has a vinyl group. It is preferable to have it.

In the present embodiment, the content of the silane coupling agent (C) in the silicone rubber-based curable composition is 5 parts by weight or more with respect to 100 parts by weight of the vinyl group-containing linear organopolysiloxane (A-1). It is preferably 100 parts by weight or less, and more preferably 5 parts by weight or more and 40 parts by weight or less.
By setting the content of the silane coupling agent (C) to be equal to or higher than the above lower limit value and lower than the upper limit value, the wiring and the substrate have appropriate adhesion, and when silica particles (B) are used, they are cured. It can contribute to the improvement of the mechanical strength of the entire object.

(Platinum or platinum compound (D))
The silicone rubber-based curable composition of the present embodiment can contain platinum or a platinum compound (D).
Platinum or the platinum compound (D) is a component that acts as a catalyst during curing of the silicone rubber-based curable composition of the present embodiment.

As the platinum or the platinum compound (D), known ones can be used, for example, platinum black, platinum supported on silica, carbon black or the like, platinum chloride acid or an alcohol solution of platinum chloride acid, chloride. Examples thereof include a complex salt of platinum acid and olefin, and a complex salt of platinum chloride acid and vinyl siloxane.
As the platinum or the platinum compound (D), only one type may be used alone, or two or more types may be used in combination.

In the present embodiment, the content of platinum or the platinum compound (D) in the silicone rubber-based curable composition is not particularly limited, but is a vinyl group-containing linear organopolysiloxane (A-1) and silica particles (B). ), The platinum group metal in the platinum compound (D) is preferably 0.01 to 1000 ppm by weight, preferably 0.1 to 500 ppm, based on the total amount of the silane coupling agent (C). Is more preferable.
By setting the content of platinum or the platinum compound (D) to the above lower limit value or more, the silicone rubber-based curable composition can be cured at an appropriate rate. Further, by setting the content of platinum or the platinum compound (D) to the above upper limit value or less, it is possible to contribute to cost reduction in producing a silicone rubber-based curable composition.

(Water (E))
Further, the conductive composition of the present embodiment may contain water (E).
As a result, the above-mentioned silane coupling agent (C) is hydrolyzed, and the desired effect is easily exhibited.
When water (E) is contained, the content thereof can be appropriately set. Specifically, for example, 10 to 100 parts by weight with respect to 100 parts by weight of the silane coupling agent (C). It is preferably in the range of 30 to 70 parts by weight, and more preferably in the range of 30 to 70 parts by weight. As a result, the reaction between the silane coupling agent (C) and the silica particles (B) can proceed more reliably.

(Other ingredients)
Further, the silicone rubber-based curable composition of the present embodiment may contain known components to be blended in the resin composition in addition to the above components (A) to (E). For example, diatomaceous earth, iron oxide, zinc oxide, titanium oxide, barium oxide, magnesium oxide, cerium oxide, calcium carbonate, magnesium carbonate, zinc carbonate, glass wool, mica and the like can be mentioned. In addition, dispersants, pigments, dyes, antistatic agents, antioxidants, flame retardants, thermal conductivity improvers and the like can be appropriately blended.
Further, from the viewpoint of controlling the curability of the silicone rubber-based curable composition, a reaction inhibitor can be appropriately added.

(Manufacturing method of silicone rubber-based curable composition)
Subsequently, a method for producing the silicone rubber-based curable composition according to the present embodiment will be described.
The silicone rubber-based curable composition of the present embodiment can be produced, for example, by undergoing the following steps.

[1] First, a predetermined amount of a vinyl group-containing linear organopolysiloxane (A-1), silica particles (B), and a silane coupling agent (C) are weighed, and then an arbitrary kneading device is used. By kneading, a kneaded product containing each of these components is obtained.

This kneaded product is obtained by kneading a vinyl group-containing linear organopolysiloxane (A-1) and a silane coupling agent (C) in advance, and then kneading (mixing) the silica particles (B). Is preferable. As a result, the dispersibility of the silica particles (B) is further improved.

Further, when obtaining this kneaded product, water (E) may be added to each component as needed.

Here, it is preferable that the kneading of each component goes through a first step of heating at the first temperature and a second step of heating at the second temperature. As a result, in the first step, the surface of the silica particles (B) can be surface-treated with the silane coupling agent (C), and in the second step, the silica particles (B) and the silane coupling agent (C) can be treated. By-products produced by the reaction with can be reliably removed from the kneaded product.

The first temperature is preferably about 40 to 120 ° C, more preferably about 60 to 90 ° C. The second temperature is preferably about 130 to 210 ° C, more preferably about 160 to 180 ° C.

The atmosphere in the first step is preferably an inert atmosphere such as a nitrogen atmosphere, and the atmosphere in the second step is preferably a reduced pressure atmosphere.

Further, the time of the first step is preferably about 0.3 to 1.5 hours, more preferably about 0.5 to 1.2 hours. The time of the second step is preferably about 0.7 to 3.0 hours, more preferably about 1.0 to 2.0 hours.

By setting the first step and the second step under the above-mentioned conditions, the effect can be obtained more remarkably.

[2] Next, the organohydrogenpolysiloxane (A-2) and platinum or the platinum compound (D) were weighed in a predetermined amount, and then prepared in the above step [1] using an arbitrary kneading device. By kneading these components into the kneaded product, a silicone rubber-based curable composition is obtained.

When kneading each of the components, the kneaded product prepared in advance in the step [1] and the organohydrogenpolysiloxane (A-2) are mixed with the kneaded product prepared in the step [1] and platinum or platinum. It is preferable to knead the platinum compound (D) and then knead each kneaded product. As a result, each component can be reliably dispersed.

In this step [2], the temperature at the time of kneading is preferably about 10 to 70 ° C., more preferably about 25 to 30 ° C. as the roll set temperature.
Further, the kneading time is preferably about 5 minutes to 1 hour, more preferably about 10 to 40 minutes.

The kneading device used in each of the steps [1] and [2] is not particularly limited, and for example, a kneader, two rolls, a Banbury mixer (continuous kneader), a pressurized kneader, or the like can be used.

Further, in this step [2], a reaction inhibitor such as 1-ethynyl-1-cyclohexanol may be added to the kneaded product. As a result, even if the temperature of the kneaded product is set to a relatively high temperature, the progress of the reaction of each component can be more accurately prevented or suppressed.

<Urethane rubber-based composition>
Next, an example in which the substrate according to the present embodiment is composed of a urethane rubber-based composition containing urethane rubber as the first elastomer will be described below. In this example, for example, a urethane rubber-based composition can be used as a resin composition for forming a substrate.

(Elastomer (A))
The urethane rubber-based composition contains urethane rubber as the elastomer (A). Examples of urethane rubber include polyester urethane and polyether urethane when classified by molecular structure. The elastomer (A) may contain only one of these urethane rubbers, or may contain two or more of them. Further, the urethane rubber may be either a thermosetting type or a thermoplastic type.

In the present embodiment, the content of the elastomer (A) in the urethane rubber-based composition is preferably 90% by mass or more, preferably 91% by mass or more, based on the total solid content of the urethane rubber-based composition. More preferably, it is more preferably 92% by mass or more. The content of the elastomer (A) in the urethane rubber-based composition is preferably 99.9% by mass or less, preferably 99.5% by mass or less, based on the total solid content of the urethane rubber-based composition. It is more preferable that the amount is 99.0% by mass or less. By setting the content of the elastomer (A) to the above lower limit value or more, a urethane rubber-based composition having a urethane rubber-based composition having high insulating properties can be obtained.

As the urethane rubber-based composition, for example, a commercially available urethane rubber can be used.

<Fluororubber composition>
Next, an example in which the substrate according to the present embodiment is composed of a fluororubber-based composition containing fluororubber as the first elastomer will be described below. That is, the fluororubber-based composition can be used as the resin composition for forming a substrate.

(Elastomer (A))
The fluororubber-based composition contains fluororubber as the elastomer (A). Examples of the fluororubber include vinylidene fluoride rubber, ethylene tetrafluoride-propylene rubber, and ethylene tetrafluoride-perfluoromethyl vinyl ether rubber. The elastomer (A) may contain only one of these as the fluororubber, or may contain two or more of them.

In the present embodiment, the content of the elastomer (A) in the fluororubber composition is preferably 85% by mass or more, preferably 87% by mass or more, based on the total solid content of the fluororubber composition. More preferably, it is more preferably 90% by mass or more. The content of the elastomer (A) in the fluororubber composition is preferably 99% by mass or less, more preferably 98% by mass or less, based on the total solid content of the fluororubber composition. It is preferably 97% by mass or less, and more preferably 97% by mass or less. By setting the content of the elastomer (A) to the above lower limit value or more, the chemical resistance and heat resistance of the substrate can be further improved. Further, by setting the content of the elastomer (A) to the above upper limit value or less, the workability can be further improved.

(Other ingredients)
The fluororubber-based composition of the present embodiment may contain a plasticizer and a filler, if necessary. Workability can be further improved by including a plasticizer. Further, by adding a filler, the characteristics of the composition can be adjusted.

The fluororubber-based composition is obtained by mixing each of the above components.

As the substrate according to the present embodiment, a commercially available plate-shaped resin or sheet-shaped resin that has been processed as necessary may be used.

[Conductive resin composition]
The wiring according to this embodiment is made of a conductive resin composition. The conductive resin composition preferably contains a second elastomer. Then, a wiring board having excellent elasticity can be realized. As the second elastomer, for example, silicone rubber, fluororubber, nitrile rubber, acrylic rubber, styrene rubber, chloroprene rubber, ethylene propylene rubber, urethane rubber and the like can be used. Among these, the second elastomer contained in the wiring is preferably one or more materials selected from the group consisting of silicone rubber, urethane rubber and acrylic rubber. When the second elastomer contains silicone rubber, a wiring board having excellent elasticity, heat resistance, chemical stability, and biocompatibility can be obtained. Further, when the second elastomer contains urethane rubber, a wiring board having excellent elasticity, mechanical strength, and abrasion resistance can be realized. However, the conductive resin composition does not have to contain an elastomer, and may contain a resin other than the elastomer.

The conductive resin composition will be described below by taking the case where the second elastomer contains silicone rubber as an example.

(Elastomer (A))
As the elastomer (A) contained in the conductive resin composition, those exemplified as the elastomer (A) contained in the silicone rubber-based curable composition can be used. Further, the preferable conditions are the same as those of the elastomer (A) contained in the silicone rubber-based curable composition except for the points described below.

In the present embodiment, the content of the elastomer (A) in the conductive resin composition is preferably 3% by mass or more, preferably 5% by mass or more, based on the total solid content of the conductive resin composition. More preferably, it is more preferably 7% by mass or more. The content of the elastomer (A) in the conductive resin composition is preferably 30% by mass or less, more preferably 25% by mass or less, based on the total solid content of the conductive resin composition. It is preferably 20% by mass or less, and more preferably 20% by mass or less.
By setting the content of the elastomer (A) to the above lower limit value or more, the cured product of the conductive resin composition can have appropriate flexibility. Further, by setting the content of the elastomer (A) to the above upper limit value or less, the mechanical strength of the cured product can be improved.

(Silica particles (B))
The conductive resin composition of the present embodiment may contain silica particles (B), if necessary. By including the silica particles (B), the hardness and mechanical strength of the cured product formed from the conductive resin composition can be improved. As the silica particles (B) contained in the conductive resin composition, those exemplified as the silica particles (B) contained in the silicone rubber-based curable composition can be used. Further, the preferable conditions are the same as those of the silica particles (B) contained in the silicone rubber-based curable composition except for the points described below.

In the present embodiment, the content of the silica particles (B) in the conductive resin composition is preferably 1% by mass or more, preferably 2% by mass or more, based on the total solid content of the conductive resin composition. More preferably, it is more preferably 3% by mass or more. The content of the silica particles (B) in the conductive resin composition is preferably 15% by mass or less, and preferably 12% by mass or less, based on the total solid content of the conductive resin composition. More preferably, it is 10% by mass or less.
By setting the content of the silica particles (B) to be equal to or higher than the above lower limit value and lower than the upper limit value, the cured product of the conductive resin composition can have appropriate mechanical strength. Further, by setting the content of the silica particles (B) to the above upper limit value or less, the cured product can have appropriate conductive properties.

(Silane Coupling Agent (C))
The conductive resin composition of the present embodiment may contain a silane coupling agent (C). This silane coupling agent (C) has a hydrolyzable group, and this hydrolyzable group is hydrolyzed by water to become a hydroxyl group, and this hydroxyl group undergoes a dehydration condensation reaction with the hydroxyl group on the surface of the silica particles (B). By doing so, the surface of the silica particles (B) can be modified.
In addition, even when the silica particles (B) are not present, the effect of improving the adhesion between the wiring and the substrate can be exhibited.
As the silane coupling agent (C) contained in the conductive resin composition, those exemplified as the silane coupling agent (C) contained in the silicone rubber-based curable composition can be used. Further, the preferable conditions are the same as those of the silane coupling agent (C) contained in the silicone rubber-based curable composition except for the points described below.

In the present embodiment, the content of the silane coupling agent (C) in the conductive resin composition is preferably 0.1% by mass or more with respect to the total solid content of the conductive resin composition, and is 0. It is more preferably 3% by mass or more, and further preferably 0.5% by mass or more. The content of the silane coupling agent (C) in the conductive resin composition is preferably 5% by mass or less, preferably 4% by mass or less, based on the total solid content of the conductive resin composition. More preferably, it is more preferably 3% by mass or less.
By setting the content of the silane coupling agent (C) to be equal to or higher than the above lower limit value and lower than the upper limit value, the wiring has appropriate adhesion to the substrate, and when silica particles (B) are used, a cured product is used. It can contribute to the improvement of mechanical strength as a whole. Further, by setting the content of the silane coupling agent (C) to the above upper limit value or less, the wiring which is a cured product can have an appropriate conductive property.

(Platinum or platinum compound (D))
The conductive resin composition of the present embodiment can contain platinum or a platinum compound (D).
Platinum or the platinum compound (D) is a component that acts as a catalyst during curing of the conductive resin composition of the present embodiment. As the platinum or platinum compound (D) contained in the conductive resin composition, those exemplified as the platinum or platinum compound (D) contained in the silicone rubber-based curable composition can be used. Further, the preferable conditions are the same as those of platinum or the platinum compound (D) contained in the silicone rubber-based curable composition except for the points described below.

In the present embodiment, the content of platinum or the platinum compound (D) in the conductive resin composition is preferably 0.001 ppm or more with respect to the total weight of the solid content of the conductive resin composition. It is more preferably 0.005 ppm or more, and further preferably 0.01 ppm or more. The content of platinum or the platinum compound (D) in the conductive resin composition is preferably 2000 ppm or less, preferably 1000 ppm or less, based on the total weight of the solid content of the conductive resin composition. Is more preferable, and 500 ppm or less is further preferable.
By setting the content of platinum or the platinum compound (D) to the above lower limit value or more, the conductive resin composition can be cured at an appropriate rate. Further, by setting the content of platinum or the platinum compound (D) to the above upper limit value or less, it is possible to contribute to cost reduction in producing the conductive resin composition.

(Water (E))
Further, the conductive composition of the present embodiment may contain water (E).
As a result, the above-mentioned silane coupling agent (C) is hydrolyzed, and the desired effect is easily exhibited.
The amount of water (E) added is arbitrary.

(Conductive filler)
The conductive resin composition of the present embodiment contains a conductive filler. That is, the wiring contains a conductive filler. By doing so, the conductivity of the wiring can be increased. The conductive filler is not particularly limited, and is, for example, copper, silver, gold, nickel, tin, lead, zinc, bismuth, antimon, or a metal powder obtained by alloying these, a conductive organic compound, or a conductive carbon material. It can include at least one of them, or two or more of them. Examples of the carbon material include carbon nanotubes and carbon nanofibers.

Of these, the conductive filler preferably contains one or more materials selected from the group consisting of silver powder, copper powder and carbon materials because of their high conductivity and high availability. As these conductive fillers, those coated with other kinds of metals can also be used.

In the present embodiment, the shape of the conductive filler is not limited, but conventionally used ones such as dendritic, spherical, and flaky can be used.

In the present embodiment, the content of the conductive filler in the conductive resin composition is preferably 60% by mass or more, preferably 65% by mass or more, based on the total solid content of the conductive resin composition. Is more preferable, and 70% by mass or more is further preferable. The content of the conductive filler in the conductive resin composition is preferably 90% by mass or less, more preferably 88% by mass or less, based on the total solid content of the conductive resin composition. , 85% by mass or less, more preferably.
By setting the content of the conductive filler to the above lower limit value or more, the cured product of the conductive resin composition can have appropriate conductive properties. Further, by setting the content of the conductive filler to the above upper limit value or less, the cured product can have appropriate flexibility.

(Other ingredients)
Further, the conductive resin composition of the present embodiment may contain known components to be blended in the resin composition in addition to the above components (A) to (E). For example, diatomaceous earth, iron oxide, zinc oxide, titanium oxide, barium oxide, magnesium oxide, cerium oxide, calcium carbonate, magnesium carbonate, zinc carbonate, glass wool, mica and the like can be mentioned. In addition, dispersants, pigments, dyes, antistatic agents, antioxidants, flame retardants, thermal conductivity improvers and the like can be appropriately blended.
Further, from the viewpoint of controlling the curability of the conductive resin composition, a reaction inhibitor can be appropriately added.

(Manufacturing method of conductive resin composition)
Subsequently, a method for producing the conductive resin composition according to the present embodiment will be described.
The conductive resin composition of the present embodiment can be produced, for example, by undergoing the following steps.

First, a silicone-based curable composition is obtained in the same manner as in steps [1] and [2] of the method for producing a silicone-based curable composition described above. The preferable conditions in each step of the method for producing the conductive resin composition are the same as the conditions described in the method for producing the silicone-based curable composition.

A conductive resin composition can be obtained by dissolving the obtained silicone rubber-based curable composition in a solvent and adding a conductive filler.
The solvent used here may be appropriately selected from the solvents capable of uniformly dissolving or dispersing the above-mentioned formulation.

Specific examples of solvents include aliphatic hydrocarbons such as pentane, hexane, cyclohexane, heptane, methylcyclohexane, ethylcyclohexane, octane and tetradecane; benzene, toluene, ethylbenzene, xylene, trifluoromethylbenzene and benzotrifluoride. Aromatic hydrocarbons such as: diethyl ether, diisopropyl ether, dibutyl ether, cyclopentyl methyl ether, cyclopentyl ethyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, 1,4-dioxane, 1,3-dioxane, tetrahydrofuran Ethers such as dichloromethane, chloroform, 1,1-dichloroethane, 1,2-dichloroethane, 1,1,1-trichloroethane, 1,1,2-trichloroethane and other haloalcans; N, N-dimethylformamide, N, Carboxylamides such as N-dimethylacetamide; sulfoxides such as dimethylsulfoxide and diethylsulfoxide can be exemplified.
As the solvent, one of these may be used alone, or two or more kinds of solvents may be mixed and used in an arbitrary ratio.

In this embodiment, a method for producing a conductive resin composition using a silicone rubber-based curable resin composition has been described, but the present invention is not limited to this, and a known method may be used depending on the type of elastomer used. It can be used as appropriate.

For example, when urethane rubber is used as the second elastomer, a conductive resin composition can be produced by adding a conductive filler to the aqueous dispersion of urethane elastomer particles.

Further, as the conductive resin composition, a commercially available conductive composition may be used. As the conductive resin composition, CI-1036 (manufactured by Engineered Materials Systems, Inc.), SX-ECA48 (manufactured by Cemedine Co., Ltd.) and the like can be used.

Further, when the wiring and the substrate are formed by using the silicone rubber-based curable composition, the silicone rubber-based curable composition used may have the same composition for each component, or may have different compositions. There may be.

Of the first elastomer and the second elastomer, at least one preferably contains a crosslinked product (a) of a vinyl group-containing linear organopolysiloxane (A-1), and among them, the first elastomer is vinyl. It is preferable to contain a crosslinked product (a) of a group-containing linear organopolysiloxane (A-1). Further, it is more preferable that both the first elastomer and the second elastomer contain a crosslinked product (a) of a vinyl group-containing linear organopolysiloxane (A-1).

Further, the crosslinked product (a) is more preferably a crosslinked product of a vinyl group-containing linear organopolysiloxane (A-1) and an organohydrogenpolysiloxane (A-2).

Further, at least one of the first elastomer and the second elastomer preferably contains silica particles (B), and both the first elastomer and the second elastomer may contain silica particles (B). More preferred.

The manufacturing method of the wiring board according to this embodiment will be described below.
The manufacturing method includes a step of preparing a substrate containing the first elastomer and a step of forming wiring on at least one surface of the substrate. Each process will be described in detail below.

First, in the step of preparing the substrate, the above-mentioned silicone rubber-based curable composition is hot-pressed in the mold to form a sheet. In this hot press, for example, the heating temperature can be 100 ° C. or higher and 250 ° C. or lower, the pressure can be 0.5 MPa or higher and 20 MPa or lower, and the hot press time can be 1 minute or longer and 30 minutes or lower. Further, after molding by a hot press, it can be post-baked (secondarily cured) at 200 ° C. for 1 to 4 hours. The thickness of the substrate is not particularly limited, but is preferably 3000 μm or less, more preferably 1000 μm or less, and further preferably 500 μm or less. The thickness of the substrate is, for example, 0.5 μm or more.

Next, in the step of forming the wiring, a pattern to be a wiring is printed and applied to the substrate by a known method such as screen printing, inkjet printing, gravure printing, and a dispenser, using the above-mentioned conductive resin composition as ink. Heat it in the oven to form the wiring. At this time, the heating temperature can be, for example, 100 ° C. or higher and 300 ° C. or lower. The heating time can be, for example, 20 minutes or more and 30 hours or less. In this way, a wiring board is obtained. A coating layer or the like may be further provided on the wiring. The coating layer can be formed by applying, for example, a resin composition similar to that of a substrate.

FIG. 1 is a cross-sectional view showing a configuration example of the electronic device 100 according to the present embodiment. The electronic device 100 according to the present embodiment includes the wiring board 10 according to the present embodiment. The wiring board 10 includes a board 11 and a wiring 13. Wiring 13 is provided on one surface 110 of the substrate 11. Further, the electronic device 100 includes an element 20. The element 20 is, for example, an electronic element such as a semiconductor integrated circuit (IC), a resistor, or a capacitor. The element 20 includes an electrode 22. The electrode 22 is connected to the electrode 22 of another element 20, a power source, or the like via a wiring 13.

The electronic device 100 is not particularly limited, but functions as, for example, a wearable sensor device or a communication device.

In the example of this figure, an example in which the wiring 13 is formed only on one surface 110 of the substrate 11 is shown, but the structure is not limited to this. The wiring may be formed on both sides of the substrate. Further, a conductive portion that penetrates the substrate and electrically connects the wirings on both sides of the substrate may be provided.

Next, the operation and effect of this embodiment will be described. The wiring board according to this embodiment has high reliability and durability as a device when used for a device to be worn on human skin such as a wearable device. Needless to say, the wiring board according to the present embodiment exhibits high reliability and durability in applications other than wearable devices.

Hereinafter, the present embodiment will be described in detail with reference to Examples. The present embodiment is not limited to the description of these examples.

[Manufacturing of wiring board]
(Example 1)
<Preparation of silicone rubber-based composition>
In this example, the materials used for producing the silicone rubber-based composition 1 are as follows.

First Vinyl Group-Containing Linear Organopolysiloxane (A-1 (a)): A vinyl group-containing linear organopolysiloxane synthesized according to the following formula was used.

That is, in a 300 mL separable flask having a cooling tube and a stirring blade substituted with Ar gas, 74.7 g (252 mmol) of octamethylcyclotetrasiloxane, 2,4,6,8-tetramethyl2,4,6,8- 0.086 g (0.25 mmol) of tetravinylcyclotetrasiloxane and 0.1 g of potassium silicate were added, the temperature was raised, and the mixture was stirred at 120 ° C. for 30 minutes. At this time, an increase in viscosity was confirmed.

Then, the temperature was raised to 155 ° C., and stirring was continued for 3 hours. Then, after 3 hours, 0.1 g (0.6 mmol) of 1,3-divinyltetramethyldisiloxane was added, and the mixture was further stirred at 155 ° C. for 4 hours.

After 4 hours, the mixture was diluted with 250 mL of toluene and washed 3 times with water. The organic layer after washing was washed several times with 1.5 L of methanol to reprecipitate and separate the oligomer and the polymer. The obtained polymer was dried under reduced pressure at 60 ° C. overnight to obtain a first vinyl group-containing linear organopolysiloxane (A-1 (a)) (vinyl group content 0.13 mol%, Mn = 277,734, Mw = 573,906, IV value (dl / g) = 0.89).

Second vinyl group-containing linear organopolysiloxane (A-1 (b)): 0.86 g (2,4,6,8-tetramethyl 2,4,6,8-tetravinylcyclotetrasiloxane). A vinyl group-containing linear organopolysiloxane synthesized in the same manner as in the above (A-1 (a)) was used except that 2.5 mmol) was used. (Vinyl group content: 0.92 mol%).

Linear Organohydrogenpolysiloxane (A-2 (a)): Organohydrogenpolysiloxane represented by the following formula (5) (manufactured by Momentive Performance Materials LLC, trade name "88466", formula (5) In, m = 14, n = 11)

Silica particles (B): manufactured by Nippon Aerosil Co., Ltd., trade name "AEROSIL300", specific surface area: 300 m ² / g, average primary particle size: 7 nm

Silane coupling agent (C-1): Hexamethyldisilazane (manufactured by Gelest)

Platinum compound (D): PLATINUM DIVINYLTRAMETHYLDISILOXASE COMPLEX (in xylene) (manufactured by Gelest, trade name "SIP6831.2", platinum content: 2.1 to 2.4 wt%)

Water (E): Pure water

Reaction inhibitor: 1-ethynyl-1-cyclohexanol (manufactured by Tokyo Kasei Co., Ltd.)

80 parts by weight of the first vinyl group-containing linear organopolysiloxane (A-1 (a)), 20 parts by weight of the second vinyl group-containing linear organopolysiloxane (A-1 (b)), Weigh 40 parts by weight of silica particles (B), 10.5 parts by weight of silane coupling agent (C-1), and 5.25 parts by weight of water (E), and then a kneading device (Co., Ltd.). By kneading with a hydraulic pressure type kneader manufactured by Moriyama), a kneaded product containing each of these components was obtained.
The kneading here was carried out in the first step under a nitrogen atmosphere at 60 to 90 ° C. for 1 hour, and then in the second step under a reduced pressure atmosphere at 160 ° C. for 1 hour.

Subsequently, with respect to 100 parts by weight of the kneaded product, 0.42 parts by weight of the linear organohydrogenpolysiloxane (A-2 (a)), 0.05 parts by weight of the platinum compound (D), and a reaction inhibitor were added. Weighed 0.1 parts by weight, these components were further added to the kneaded product obtained above, and kneaded using a kneading device (manufactured by Kansai Roll Co., Ltd., roll machine). As a result, a silicone rubber-based composition 1 was obtained as a silicone rubber-based curable composition. At this time, the content of platinum in the silicone rubber-based curable composition is 10 to 13 ppm with respect to the total weight of the solid content of the silicone rubber-based curable composition.

<Preparation of conductive resin composition>
The silicone rubber-based composition 1 obtained above was immersed in 2.33 times the amount of tetradecane, and then stirred with a rotation / revolution mixer to prepare a solution. A conductive resin composition 1 was obtained by adding silver powder (manufactured by DOWA Electronics Co., Ltd., trade name "3-8F") as the conductive filler 1 to this solution. At this time, the solid content of the silicone rubber-based composition 1 was 15 parts by mass and the content of the conductive filler 1 was 85 parts by mass with respect to 100 parts by mass of the solid content of the conductive resin composition 1.

<Formation of wiring board>
The silicone rubber-based composition 1 was hot-pressed in the mold to obtain a sheet having a thickness of 150 mm × 150 mm and a thickness of 1 mm. In this hot press, the heating temperature was 170 ° C., the pressure was 10 MPa, and the hot press time was 5 minutes. Then, it was post-baked (secondary curing) at 200 ° C. for 4 hours. A part of this sheet was cut out to a size of 20 mm × 50 mm and a thickness of 1 mm to obtain a substrate. In this hot press, the heating temperature was 170 ° C., the pressure was 10 MPa, and the hot press time was 5 minutes. Then, it was post-baked (secondary curing) at 200 ° C. for 4 hours.

Next, a pattern serving as wiring was printed and applied to the main surface of the substrate using the above-mentioned conductive resin composition 1 as ink by screen printing. It was heated in an oven to form the wiring. At this time, the heating temperature was set to 200 ° C. and the heating time was set to 2 hours. The wiring pattern was 0.5 mm in width, 50 μm in thickness, and 30 mm in length.

(Example 2)
A wiring board was obtained in the same manner as in Example 1 except that the substrate was formed by using the silicone rubber-based composition 2 described below instead of the silicone rubber-based composition 1.

The first vinyl group-containing linear organopolysiloxane (A-1 (a)) and the second vinyl group-containing linear organopolysiloxane (A-1 (b)) used in the preparation of the silicone rubber-based composition 2. )), Silane particles (B), silane coupling agent (C-1), and water (E) are the same materials used in the preparation of the silicone rubber-based composition 1, respectively. Further, in the preparation of the silicone rubber-based composition 2, 1,3-divinyl disilazane (manufactured by Gelest) was further used as the silane coupling agent (C-2).

80 parts by weight of the first vinyl group-containing linear organopolysiloxane (A-1 (a)), 20 parts by weight of the second vinyl group-containing linear organopolysiloxane (A-1 (b)), 50 parts by weight of silica particles (B), 9.5 parts by weight of silane coupling agent (C-1), 1.0 parts by weight of silane coupling agent (C-2), and 5 parts by weight of water (E). A kneaded product containing each of these components was obtained by weighing .25 parts by weight and then kneading with a kneading device (manufactured by Moriyama Co., Ltd., hydraulic pressure type kneader).
The kneading here was carried out in the first step under a nitrogen atmosphere at 60 to 90 ° C. for 1 hour, and then in the second step under a reduced pressure atmosphere at 160 ° C. for 1 hour.

Subsequently, with respect to 100 parts by weight of the kneaded product, 0.84 parts by weight of the linear organohydrogenpolysiloxane (A-2 (a)), 0.05 parts by weight of the platinum compound (D), and a reaction inhibitor. Weighed 0.1 parts by weight, these components were further added to the kneaded product obtained above, and kneaded using a kneading device (manufactured by Kansai Roll Co., Ltd., roll machine). As a result, a silicone rubber-based composition 2 was obtained as a silicone rubber-based curable composition. At this time, the content of platinum in the silicone rubber-based curable composition is 10 to 13 ppm with respect to the total weight of the solid content of the silicone rubber-based curable composition.

Hereinafter, wiring was formed with the conductive resin composition 1 in the same manner as in Example 1 to obtain a wiring board.

(Example 3)
In Example 3, a wiring board was obtained in the same manner as in Example 1 except for the points described below.

In this embodiment, it is cut out from a polyester urethane sheet (hardness 30, thickness 1 mm, width 1000 mm × length 2000 mm, rubber product code 10199-0005-9) purchased by Fuso Rubber Sangyo Co., Ltd., and 20 mm × A substrate having a size of 50 mm was prepared.

Next, a pattern serving as wiring was printed and applied to the main surface of the substrate using the above-mentioned conductive resin composition 1 as ink by screen printing. It was heated in an oven to form the wiring. At this time, the heating temperature was 120 ° C. and the heating time was 2 hours. The wiring pattern was 0.5 mm in width, 50 μm in thickness, and 30 mm in length.

(Example 4)
A wiring board was obtained in the same manner as in Example 1 except that a substrate having a size of 20 mm × 50 mm was prepared by cutting out from a fluororubber sheet (thickness 1 mm, manufactured by Kureha Elastomer Co., Ltd., FB760N). .. Wiring was formed on the prepared substrate with the conductive resin composition 1 in the same manner as in Example 1 to obtain a wiring substrate.

(Example 5)
In Example 5, a wiring board was obtained in the same manner as in Example 1 except for the points described below.

In this embodiment, it is cut out from a plate-shaped polyether urethane sheet (hardness 90, thickness 1 mm, width 1000 mm × length 2000 mm, rubber communication product code 10005-0002-0) purchased by Fuso Rubber Industry Co., Ltd. Then, a substrate having a size of 20 mm × 50 mm was prepared.

Next, a pattern serving as wiring was printed and applied to the main surface of the substrate using the conductive resin composition 2 described later by screen printing as ink. It was heated in an oven to form the wiring. At this time, the heating temperature was 120 ° C. and the heating time was 2 hours. The wiring pattern was 0.5 mm in width, 50 μm in thickness, and 30 mm in length.

As the conductive resin composition 2, CI-1036 (Engineered Materials Systems, Inc.) was used. The conductive resin composition 2 contained silver powder as a conductive filler.

(Comparative Example 1)
A wiring board was obtained in the same manner as in Example 1 except that the substrate was formed by using the urethane rubber-based composition 1 described below instead of the silicone rubber-based composition 1.

As the urethane rubber-based composition 1, water-dispersed urethane (Dispacol U42 manufactured by Sumika Bayer Urethane Co., Ltd.) was used.

In this comparative example, the urethane rubber-based composition 1 was poured into a mold and air-dried for 3 days to obtain a sheet having a thickness of 150 mm × 150 mm and a thickness of 1 mm. Then, a substrate was obtained by cutting out a part from this sheet. The size and thickness of the substrate were 20 mm × 50 mm, and the thickness was 1 mm. Hereinafter, wiring was formed with the conductive resin composition 1 in the same manner as in Example 1 to obtain a wiring board.

[Evaluation of board]
The substrates in each example and comparative example in the state where the wiring was not formed were evaluated as follows.

<Board weight>
_{The weight W 0} of the substrate before the test was measured. Then, the entire substrate was immersed in an acidic artificial sweat solution defined by JIS L0848 in a closed container. The temperature of the acidic artificial sweat solution was 25 ° C., and the mixture was allowed to stand for 7 days. After standing, the substrate was taken out from the acidic artificial sweat solution, water on the surface was removed, and the weight Wa after the test was measured. Further, the substrate was dried at 40 ° C. for 4 hours, and the weight Wb after drying was measured.

Then, the ratio WRa of the weight Wa after the test to the weight W _{0 before the test was obtained from the relationship of WRa = Wa / W 0} × 100 [%]. Further, to determine the ratio WRb weight Wb after testing and drying to the weight _{W 0} before the test from _{WRb = Wb / W 0 × 100} [%] of the relationship. Further, the ratio WRd of the water content of the substrate after the test to the weight W _{0 before the test was determined from the relationship of WRd = (Wa-Wb) / W 0} × 100 [%].

[Durability evaluation of wiring board]
The wiring boards of each Example and Comparative Example were evaluated as follows. The results are summarized in Table 1.

For the wiring board, the resistance value R _ini before the durability test of the wiring was measured in a non-expandable state. Then, only the surface of the wiring board opposite to the surface on which the wiring was formed was brought into contact with the non-woven fabric impregnated with the acidic artificial sweat liquid defined by JIS L0848 in a closed container. The temperature of the acidic artificial sweat solution was 25 ° C., and the mixture was allowed to stand for 7 days. After standing, the wiring board was removed from the non-woven fabric impregnated with the acidic artificial sweat liquid, and the resistance value _Rex of the wiring in the first extended state was measured. The extension was performed in the length direction of the wiring. Moreover, the length of the wiring at the time of extension was made the same in each Example and Comparative Example. _{Next, the resistance value R re} in the state of returning to the original length from the first extended state (non-expandable state) was measured. The ratio R _ex / R _re of the resistance value R _{ex to the resistance value R re} was calculated. The calculated ratio R _ex / R _re was evaluated as "⊚" when it was less than 2, "◯" when it was 2 or more and less than 10, and "x" when it was 10 or more. In each of the examples and comparative examples, the substrate and the wiring had sufficient adhesion, and the resistance value could be evaluated without peeling. The ratio R _re / R _{ini of} the resistor R _ini and the resistor R _re is also shown in Tables 1 and 2.

As shown in Table 1 and Table 2, in Examples 1 to 5 in the range WRd following 3.0% _0%, the value of _R ex _/ R _re small, high wiring board durable Was confirmed. Among them, WRD in 0% to 0.5% or less in Examples 1 and _2, the value of _R ex _/ R _re becomes 1.5 or less, was the high particularly durable. On the other hand, in Comparative Example 1 WRd exceeds 9% was large _R ex _{/ R re.} It is considered that this is because there are many cracks in the wiring and the resistance in the extended state is increased. As described above, in the wiring board of Comparative Example 1, deterioration of the wiring due to the artificial sweat liquid was confirmed, and it was found that there was a problem in durability when used in a device mounted on the human body.

The results of the substrate evaluation and the durability evaluation of the wiring board are summarized in Tables 1 and 2.

[Evaluation of substrate hardness and strength]

The hardness and strength of the substrates of Examples 1 to 5 and Comparative Example 1 in the state where no wiring was formed were further evaluated as follows. The results are shown in Tables 3 and 4 together with the judgment results of the durability evaluation of the wiring board described above.

<Hardness of substrate>
A test piece was cut out from the sheet before cutting out the substrate, and the hardness Ha before the immersion test was measured at 25 ° C. by a type A durometer specified in JIS K6253. Then, the entire test piece was immersed in an acidic artificial sweat solution defined by JIS L0848 in a closed container. The temperature of the acidic artificial sweat solution was 25 ° C., and the mixture was allowed to stand for 7 days. After standing, the test piece was taken out from the acidic artificial sweat solution, and the hardness Hb after the immersion test was measured at 25 ° C. by a type A durometer specified in JIS K6253. Then, a value represented by (Hb-Ha) / Ha × 100 [%] was calculated.

<Tear strength of substrate>
A crescent-shaped test piece was prepared from the sheet before cutting out the substrate, and the tear strength TRa [N / mm] before the immersion test was measured according to JIS K6252. On the other hand, the entire sheet piece separately cut out from the sheet was immersed in an acidic artificial sweat solution specified by JIS L0848 in a closed container. The temperature of the acidic artificial sweat solution was 25 ° C., and the mixture was allowed to stand for 7 days. After standing, a sheet piece was taken out from the acidic artificial sweat solution, and a crescent-shaped test piece was prepared from the sheet. The tear strength TRb [N / mm] after the immersion test was measured for the obtained test piece according to JIS K6252. Then, a value represented by (TRb-TRA) / TRa × 100 [%] was calculated.

<Tensile strength of substrate>
A No. 3 tumbler-shaped test piece was prepared from the sheet before cutting out the substrate, and the tensile strength TBa [N / mm ² ] before the immersion test was measured according to JIS K7161. On the other hand, the entire sheet piece separately cut out from the sheet was immersed in an acidic artificial sweat solution specified by JIS L0848 in a closed container. The temperature of the acidic artificial sweat solution was 25 ° C., and the mixture was allowed to stand for 7 days. After standing, a sheet piece was taken out from the acidic artificial sweat solution, and a No. 3 tumbler-shaped test piece was prepared from the sheet piece. The tensile strength TBb [N / mm ² ] after the immersion test was measured for the obtained test piece according to JIS K7161. Then, a value represented by (TBb-TBa) / TBa × 100 [%] was calculated.

As shown in Tables 3 and 4, the durability of the wiring board was high in Examples 1 to 5 in which the value of (Hb-Ha) / Ha × 100 [%] was −10% or more. Further, the durability of the wiring board was high in Examples 1 to 5 in which the value of (TRb-TRA) / TRa × 100 [%] was −40% or more. The durability of the wiring board was high in Examples 1 to 5 in which the value of (TBb-TBa) / TBa × 100 [%] was −50% or more.

Although the embodiments of the present invention have been described above with reference to the drawings, these are examples of the present invention, and various configurations other than the above can be adopted.
Hereinafter, an example of the reference form will be added.
1. 1. With an elastic substrate,
A wiring board in which elastic and conductive wiring is laminated.
The weight of the substrate before the test of immersing in the acidic artificial sweat solution defined by JIS L0848 at 25 ° C. for 7 days was set to W _0, and the weight of the substrate after the test was set to Wa, and the test was performed. Then, when the weight of the substrate after further drying at 40 ° C. for 4 hours is Wb, the _{value represented by (Wa-Wb) / W 0} × 100 [%] is 3.0%. The following wiring board.
2. 1. 1. The wiring board described in
The wiring is a wiring board containing a conductive filler.
3. 3. 1. 1. Or 2. The wiring board described in
The wiring is a wiring board comprising one or more materials selected from the group consisting of silver powder, copper powder and carbon materials.
4. 1. 1. From 3. The wiring board described in any one of the above.
The substrate is a wiring substrate containing the first elastomer.
5. 4. The wiring board described in
The first elastomer contained in the substrate is a wiring board which is one or more materials selected from the group consisting of silicone rubber, fluororubber, urethane rubber and acrylic rubber.
6. 1. 1. From 5. The wiring board described in any one of the above.
The wiring is a wiring board containing a second elastomer.
7. 6. The wiring board described in
The second elastomer contained in the wiring is a wiring board which is one or more materials selected from the group consisting of silicone rubber, urethane rubber and acrylic rubber.
8. 1. 1. From 7. The wiring board described in any one of the above.
The hardness of the substrate at 25 ° C. measured by the type A durometer specified in JIS K6253 before the test is Ha, and the hardness at 25 ° C. measured by the type A durometer specified in JIS K6253 after the test is defined as Ha. A wiring board in which (Hb-Ha) / Ha × 100 [%] is -10% or more when Hb is used.
9. 1. 1. From 8. The wiring board described in any one of the above.
A notched crescent test piece was prepared from the substrate, and the test piece was subjected to the same test as the test.
When the tear strength of the test piece before the test measured by the method of JIS K6252 is TRa and the tear strength after the test measured by the method of JIS K6252 is TRb, (TRb-). A wiring board in which TRa) / TRa × 100 [%] is -40% or more.
10. 1. 1. From 9. The wiring board described in any one of the above.
When the tensile strength of the substrate before the test measured by the method of JIS K7161 is TBa and the tensile strength after the test measured by the method of JIS K7161 is TBb, (TBb-TBa). ) / TBa × 100 [%] is -50% or more and 5% or less, a wiring board.
11. 1. 1. To 10. An electronic device including the wiring board according to any one of the above.

100 Electronic device 10 Wiring board 11 Board 110 Surface 13 Wiring 20 Element 22 Electrode

Claims (8)

With an elastic substrate,
A wiring board in which elastic and conductive wiring is laminated.
The weight of the substrate before the test of immersing in the acidic artificial sweat solution specified in JIS L0848 at 25 ° C. for 7 days was set to W _0, and the weight of the substrate after the test was set to Wa, and the test was performed. Then, when the weight of the substrate after further drying at 40 ° C. for 4 hours is Wb, the _{value represented by (Wa-Wb) / W 0} × 100 [%] is 3.0%. Ri der below,
The hardness of the substrate at 25 ° C. measured by the type A durometer specified in JIS K6253 before the test is Ha, and the hardness at 25 ° C. measured by the type A durometer specified in JIS K6253 after the test. When Hb is used, (Hb-Ha) / Ha × 100 [%] is -10% or more.
A notched crescent test piece is prepared from the substrate, the test piece is subjected to the same test as the test, and the tear strength of the test piece before the test measured by the method of JIS K6252 is set to TRa. , (TRb-TRA) / TRa × 100 [%] is −40% or more, where TRb is the tear strength after the test measured by the method of JIS K6252.
When the tensile strength of the substrate before the test measured by the method of JIS K7161 is TBa and the tensile strength after the test measured by the method of JIS K7161 is TBb, (TBb-TBa). ) / TBa × 100 [%] is -50% or more and 5% or less.
Wiring board. The wiring board according to claim 1.
The wiring is a wiring board containing a conductive filler. The wiring board according to claim 1 or 2.
The wiring is a wiring board comprising one or more materials selected from the group consisting of silver powder, copper powder and carbon materials. The wiring board according to any one of claims 1 to 3.
The substrate is a wiring substrate containing the first elastomer. The wiring board according to claim 4.
The first elastomer contained in the substrate is a wiring board which is one or more materials selected from the group consisting of silicone rubber, fluororubber, urethane rubber and acrylic rubber. The wiring board according to any one of claims 1 to 5.
The wiring is a wiring board containing a second elastomer. The wiring board according to claim 6.
The second elastomer contained in the wiring is a wiring board which is one or more materials selected from the group consisting of silicone rubber, urethane rubber and acrylic rubber. An electronic device including the wiring board according to any one of claims 1 to 7.

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