JPS6276506A - Elongated conductive element - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an elongated conductive element whose electrical resistance value changes by one order of magnitude or more when elongated in any direction. More specifically, the present invention relates to an elongated conductive element in which an electrode plate is used as a lead wire connection terminal attached to an elongated conductive sheet.

[Future technology]

Conventionally, materials whose electrical resistance value decreases by σ due to elongation deformation are not widely known. Therefore, by capturing the decrease in electrical resistance value caused by elongation deformation, it is possible to determine whether or not the measured object is elongated, the amount of elongation, and the extent of elongation/compression. Elements capable of detecting frequency had also not been developed.

On the other hand, strain gauges are known as elements that take advantage of the property that electrical resistance increases with elongation and deformation. That is, for example, when thin metal cotton such as Constankun, Advance, Nichrome, etc. is pulled, the electrical resistance value increases. However, since the elongation rate of this type of metal wire is extremely small (1% or less), the strain gauge described above can only handle minute deformations of the object to be determined. It is not suitable for detecting deformation.

There are also elements using piezoelectric elements and pressure-sensitive conductive rubber. Piezoelectric elements detect mechanical strain deformation as voltage changes, but like strain gauges, they are only suitable for applications involving minute deformations. On the other hand, in the latter type of pressure-sensitive conductive rubber, the electrical resistance value decreases when subjected to compressive deformation, but does not decrease when subjected to elongated deformation.

As mentioned above, conventionally known elements can only be used for minute extensional deformations or only for compressive deformations. Therefore, if there is an element that can detect elongation deformation, especially the elongation behavior of an object that undergoes a considerable amount of elongation deformation, such as the presence or absence of elongation, the amount of elongation, and the frequency of compression accompanied by elongation, it could be applied in a wide range of fields. The current situation is that although certain things are expected, nothing that satisfies them has yet appeared.

[Problem that the invention seeks to solve]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an elongated conductive element that can electrically detect elongated deformation, particularly a considerable amount of elongated behavior, which cannot be performed using conventionally known elements.

[Means for solving problems]

An object of the present invention is to provide an elongated conductive element comprising an elongated conductive sheet and an electrode plate attached to the sheet at intervals, the electrode plate being connected to the elongated conductive element through a conductive resin layer. This is achieved by means of an extensible electrically conductive sheet, which is characterized in that it is joined to the sheet.

The elongated conductive sheet here means that when an elongated deformation action is applied, or when a deformation action such as bending or compression accompanied by elongation deformation is applied, the electrical resistance value of the sheet in the deformation direction becomes 1.
It means a sheet that decreases by more than an order of magnitude. For example, by adding a flaky conductive filler to an insulating polymer elastomer, the sheet improves conductivity in the stretching direction when stretched in a direction parallel to the plane of the filler. This sheet is included in "Deformed Conductive Polymer Elastomer" filed as Japanese Patent Application No. 59-20057 on September 27, 1982 by the same applicant as the inventor. In addition, the "deformed conductive knitted fabric" filed as Japanese Patent Application No. 60-41024 on March 4, 1985 by the same applicant as the present invention as a stretched conductive sheet has electrical insulation properties that meet the following conditions. , a knitted fabric whose electrical resistance value changes when stretched or compressed in any direction.

■ Among all the intertwined parts in a predetermined area of the knitted fabric, if the number of intertwined parts that are electrically insulated is ρ1, and the number of intertwined parts that are electrically conductive is 12, then The value of the ratio X+/l, measured per square inch, is 1
Must be 79 or above.

When is m2, any type of weave with the ratio m or /m2 may be used, but plain weave in particular has a dense structure and is excellent in repeated durability, and its resistance value changes with high sensitivity to minute deformation. Therefore, it is more preferable. In addition, the structure of the knitted fabric may be either warp knitting, single weft knitting, triconte knitting, jersey knitting, rubber knitting, purl knitting, etc., but especially in the case of purl knitting, any of the knitting Mi weaves may be used. This is more preferable since substantially uniform deformation conductivity can be obtained also in the direction. Incidentally, the deformation conductivity with respect to minute deformation and large deformation can be obtained by appropriately selecting the lJi weave of one knitted woven fabric.

The shape of the knitted fabric includes all shapes using [j] of the knitted fabric, such as sheet, cylinder, etc.

In addition, the yarns constituting the knitted fabric include monofilaments and multifilaments spun by ordinary melting or wet spinning machines, spun yarns made of staple fibers, twisted yarns of these yarns, and elongated shapes obtained by slitting films and sheets. An object or its convergence can be used. The materials include all electrically insulating synthetic polymers such as nylon and esters, synthetic fibers such as cellulose and other regenerated cellulose fibers, electrically insulating natural polymers such as natural rubber, and electrically insulating inorganic fibers such as glass. Only certain parts of these threads are electrically insulated, and other parts are plated or coated with conductive substances such as copper, nickel, silver, and carbon.

Conductivity is imparted by conductive means such as thermal spraying.

In particular, in the case of multifilaments or spun yarns, each filament or short fiber comes into contact with each other under minute stress, which is more preferable for forming a Q-woven fabric with high sensitivity deformation conductivity.

Note that the electrically insulated state here refers to the state in which the electrical resistance value between two needle terminals is determined by the method for measuring electrical resistance value described in Japanese Patent Application No. 60-41024 filed by the same applicant as the present invention. It means a state where the electrical resistance is 106Ω or more, and an electrically conductive state also means a state where the electrical resistance value between two needle terminals is 1.
This means a state where the resistance is less than 0.6Ω.

The intertwined area here refers to the area where each prefecture intersects, and does not necessarily need to be in contact. In the case of woven fabrics, it is the intersection of warp and weft yarns, and in the case of knitted fabrics, it is the intersection of loops.

The intertwined part that is electrically insulated or the intertwined part that is electrically conductive here refers to the part where two intertwined threads are electrically insulated through the intertwined part, or It means a part that is electrically conductive.

Further, the term "adjacent interlaced sections" refers more precisely to the center-to-center portions of interlaced portions, and means the center-to-center portions of adjacent interlaced portions of one thread. Also, between interlaced parts that are electrically insulated or electrically conductive means that the adjacent interlaced parts mentioned above are electrically insulated or electrically conductive. It means something. Note that the elongated W conductive sheet may be an elongated conductive structure formed by laminating an elastomer on at least one side of an elongated conductive knitted fabric, since durability and the like are improved.

The conductive resin layer in the present invention includes commonly used plastic adhesives such as epoxy, acrylic, and ester adhesives, urethane adhesives, latex adhesives, and hot-melt polymers, such as The base material is polyester or polyamide resin, and usually 5~
This layer is made of a conductive resin mixed with an appropriate amount of conductive filler within a range of 50% by volume. The conductive filler herein is made of metals such as nickel, copper, iron, aluminum, gold, and silver, or alloys thereof, or conductive carbon, and is in the form of powder or short fibers. The thickness of the conductive resin layer is required to be 1 μm or more, and although it depends on the purpose of the elongated conductive element, the thickness is usually 2 μm or more and 5 (lIim or less) for the elongated conductive sheet, electrode plate, etc. This is preferable in terms of adhesive strength, contact resistance, and cost, but is not limited to this. If the thickness of the conductive resin layer is less than 1 μm, the adhesive strength will be poor. When the base material is a polymer, it is more preferable because it can be used in the form of a sheet or film, which is excellent in terms of operability.

Next, the electrode plate referred to in the present invention' is made of copper or aluminum.

Conductive fabrics and conductive elastomers that are made of metal plates such as brass and stainless steel that are normally used as electrodes, as well as fabrics and elastomer sheets that have been given conductivity through methods such as metal knobs, coatings, five-point radiation, and the inclusion of conductive fillers. A sheet will be provided.

In addition, if the surface of the metal plate is embossed with unevenness,
It is more preferable because it has a high adhesive strength with the conductive resin layer and is more likely to cause electrical breakdown, so the amount of conductive filler mixed can be reduced, and the cost and decrease in adhesive strength of the conductive resin layer can be suppressed. .

1 to 4 show in front view the structure of several embodiments of elongated conductive elements according to the invention.

In the figure, la, Ib, lc, ld are stretched conductive sheets, 2a, 2b, 2c, 2
d is a conductive resin layer, 3a, 3b.

3c and 3d represent electrode plates. FIG. 1 shows an elongated conductive element using a metal plate as an electrode plate. FIG. 2 represents an elongated conductive element using an embossed metal plate as the electrode plate. FIG. 3 shows an elongated conductive element using conductive fabric as the electrode plate. FIG. 4 shows an elongated conductive element in which electrode plates are mounted on both ends of an elongated electrically conductive sheet.

Hereinafter, the elongated conductive element of the present invention will be described in more detail with reference to Examples, but the elongated conductive element of the present invention is not limited to those shown in these Examples or the previous schematic diagram.

C'm example] 1 example of X blade - flaky Ni-plated mica on upper polyurethane (inner diameter and [
A 220 μm thick sheet containing 15% oak (V ratio of 10:1) was prepared. Note that the surface with the inner diameter here refers to the surface with the maximum area of Ni-plated mica, and the inner diameter is the maximum value of the long axis in the surface (the longest diameter in the surface) of the surface with the maximum area. , 9. Furthermore, the thickness is the distance between two parallel plates when the surface of Ni Menoki Mite J is sandwiched between two parallel plates. This sheet was cut into pieces with a width of 5 cm and a length of 5 cm, and when stretched by 15%, the electrical resistance value decreased from 4 x 10''Ω to 40Ω.

Copper powder (particle size 5 to 10 μm) is placed on both ends of this sheet.
Polyamide heat-sealing resin sheet (thickness 2
A sample tooth 1 of an elongated conductive element according to the present invention was prepared by heat-sealing a copper plate (40 μm) through a copper plate (0 μm) under the condition of 130°C and 13 atmospheres.

Ester taffeta made by Asahi Kasei Industries (50d/24f,
75d/36f) in sodium hydroxide aqueous solution (80g
/j'), subjected to weight loss processing at 100℃ (loss rate 20%), S
nC#! z: Sensitized in a bath with hydrochloric acid in a weight ratio of 3=10, and after washing and dehydration, PdCl2:hydrochloric acid in a weight ratio of 1:1
NiC12.6HzO
, HaHPOz ・HtO, sodium citrate, NH
4 (J, Ni-plated ester taffeta was prepared by treating it at 90°C for 2 minutes in a bath with ammonia water at a weight ratio of 1:1:3:2:2. This was cut into samples of 10 cm x 10 cm in size. Double cylindrical laminar flow generator (inner cylinder rotates at high speed, outer cylinder inner diameter 25cm, inner cylinder outer diameter 10cm)
with water, and the inner cylinder rotation speed was 20 Orpm.
After processing for 0 minutes, a stretched conductive sheet was obtained. This sheet
The electrical resistance value decreased from 1.3 x 10' Ω to 30 Ω by cutting it into cm width x 5 cr Q length and elongating it by 15%.

Copper powder (particle size 5 to 10 μm) is placed on both ends of this sheet.
A polyester heat-sealing resin sheet (thickness: 20 μm) mixed with vol.
, - square C11! An elongated conductive element according to the present invention is made by heat-sealing an embossed copper plate (average thickness 40 μm) or a copper-plated fabric at 13'0°C and 13 atm, which occupies 15% of the area. 3 types of samples 1h2
, 3 and 4 were obtained, respectively.

Ester taffeta manufactured by Asahi Kasei Kogyo ■ (50d/24f,
75d/36f) in sodium hydroxide solution (80g/
/), 100°C7: NFfl processing (reduction rate 20%), 5nCj! z: Sensitized in a bath with hydrochloric acid in a weight ratio of 3:10, and after washing and dehydration, PdCffz:hydrochloric acid in a weight ratio of 1:
Activated in a bath of 15, washed with water and dehydrated to NiC ・611
20, HallPOz H) IzO, sodium citrate, NH, Cβ, aqueous ammonia in a ratio of 1:1:3:2
N1-plated ester taffeta was prepared by treating in a bath with a weight ratio of :2 at 90°C for 2 minutes. This is 10cmx]Oc
Cut the samples into m-sized samples, put them in a double cylindrical laminar flow generator (inner cylinder rotates at high speed, outer cylinder inner diameter 25 cm, inner cylinder outer diameter 10 Cffl) together with water, and adjust the inner cylinder rotational speed. A stretched conductive sheet was obtained by processing at 200 rpm for 200 minutes. Next, commercially available urethane elastomer resin (solvent DM)
F, solid content 10evt%) was coated on a release paper with a gauge of 130 μm, and then dried in a 100"c x 3" sheet and left uncoated. Thermal adhesive transfer was carried out at 110°C under pressure.Then, it was dried at 100°C for 30 minutes to produce an elongated conductive sheet with a reinforcing elastomer sheet having a thickness of 10 μm.This sheet was 1 cIn wide x 5 cm long in the bias direction. By cutting it and elongating it by 15%, the resistance value decreased from 4.5 x 10 6 Ω to 3 x 10 2 Ω. At both ends of this sheet, a polyamide heat-sealing resin mixed with 20 volume % of copper powder (particle size 5 to 10 μm) was applied. Sheet (thickness 20
Sample N115 of the elongated conductive element according to the present invention was fabricated by heat-sealing a copper plate (40 μm) under the conditions of 130° C. and 13 atm.

几fiJli Thickness 2 in which 15% by volume of flaky Ni-plated mica (in-plane diameter to thickness ratio is 10:1) is mixed into polyurethane.
Make a 20 μm sheet. Note that the surface with the inside diameter here refers to the surface with the maximum area of N1 plated mica, and the inside diameter is the maximum value of the long axis in the surface (the longest diameter in the surface) of the surface with the maximum area.XQ , 9. Further, the thickness is the distance between two parallel flat plates when the surfaces of Nj 12 chimica are sandwiched between two parallel flat plates. This sheet was cut into 1 (maximum) width x 5 cm length, and when stretched by 15%, the electrical resistance value decreased from 4 x 10 6 Ω to 40 Ω.

Next, copper powder (particle size 5 to 10 μm) was mixed into a solution of low melting point polyamide resin dissolved in methanol (304% solid content) using a knife coater (20% by volume based on the solid content).
After coating both ends of the sheet, it was dried at 100° C. for 30 minutes to form a conductive resin layer having an average thickness of 0.9 μm in sheet form. A copper plate (40μm) was placed on top of it at 130℃, 3
Comparative sample sample 6 was prepared by thermal fusion under atmospheric pressure conditions.

Next, the elongated conductive properties of the elongated conductive elements according to the present invention of samples 1Ik11 to 5 and the sample floor 6 of the comparative example, and the elongated conductive properties after 0 to 20% elongation and repetition were performed 10,000 times at a speed of 100 times/min. The adhesion of the electrode plates was also investigated, and the results are shown in Table 1 for comparison.

The elongation and cycling resistance was measured using an elongation and cycling tester (Daiei Kagaku Demuncher) at a speed of 100 times/min.
After the sample a was repeated 10,000 times at an elongation of 20% from O, the resistance value at 0.10.20% elongation was measured and compared with that before the repeated test. Stretch conductive properties are 3cm on each side.
An electrode plate was sandwiched between two square copper plates, and the electrode plate was attached to a tensile tester, and the electric resistance value for a given elongation rate was measured. Even after 10,000 repetitions of elongation, the electrode plate only cracked and the elongated conductive properties did not deteriorate at all, whereas in sample 6 of the comparative example, the thickness of the conductive resin layer was less than 1 μm. It can be seen that after 10,000 repetitions of stretching, the electrode plate cracked and the stretched conductive properties also deteriorated.

〔Effect of the invention〕

The elongated conductive element according to the present invention having the above-mentioned configuration has a high adhesive strength of the conductive resin layer, low contact resistance,
Since it has high durability against repeated stretching, it exhibits excellent performance when used as a sensor element to detect stretching behavior of objects that undergo a considerable amount of stretching deformation, especially stretching deformations that cannot be performed using conventionally known sensor elements. do.

[Brief explanation of drawings]

1 to 4 are front views showing a plurality of embodiments of the elongated W-shaped element according to the present invention, in which FIG. 1 shows a metal plate as an electrode plate, and FIG. 2 shows an embossed metal plate. 3 shows a case where a thick conductive fabric is used as an electrode plate, and FIG. 4 shows a case where electrode plates are attached to both ends of an elongated conductive sheet. la, Ib, lc, 1+l=stretched conductive sheet, 2a, 2b, 2c, 2d---conductive resin layer, 3a, 3b, 3c, 3d---・-
Electrode plate.

Claims (1)

[Claims] 1. An elongated conductive element comprising an elongated conductive sheet and an electromagnetic plate attached to the sheet at intervals, the electrode plate being joined to the elongated conductive sheet via a conductive resin layer. An elongated conductive sheet characterized by: