JP3084380B2 - Method of using and modifying conductive silicone gel material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[Object of the invention]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of using a conductive silicone gel material containing a conductive filler whose behavior has been recently revealed and a method of modifying the conductive silicone gel material. .

[0002]

BACKGROUND OF THE INVENTION Conventionally, conductive rubber containing a conductive filler in natural rubber, SBR, NBR, butyl rubber, etc. has been
As a contact element for calculators and personal computer keyboards, and as a pressure-sensitive conductive element such as a keyboard for electronic musical instruments and a variable-speed electric zoom switch for video cameras, using the relationship between the distortion and the continuous change in electrical resistance. , Widely used. Under such circumstances, the present applicant has recently paid attention to its cushioning properties and vibration damping properties, and has been applied to shoe soles, cushioning pads for various exercise equipment, O
Attention has been paid to silicone gels that are being widely used in insulators and the like of equipment A, and a conductive silicone gel material containing a conductive filler therein has been disclosed in Japanese Patent Application No. 60-1837.
No. 46 (Japanese Patent Application Laid-Open No. Sho 62-44902), and to date, the behavior of the conductive silicone gel material has been elucidated. As a result, it became clear that depending on the type of the conductive filler to be added, a behavior not seen in the conventional conductive rubber was exhibited. That is, the conductive filler to be added includes large, spherical, flaky, fibrous, and whisker-like conductive fillers. Among them, the conductive silicone gel obtained by adding the spherical or flaky conductive filler is used. The material shows a J-shaped or U-shaped conductivity curve with the compressive displacement amount taken on the horizontal axis and the electrical resistance value taken on the vertical axis, and the amount of compressive displacement, that is, when pressed and distorted, increases the electrical resistance value. Thus, the behavior was different from that of the conventional conductive rubber, fiber and whisker-like conductive filler.

For this reason, the conventional method of using a conductive rubber cannot be directly followed, and a method of using a conductive silicone gel material exhibiting such a unique behavior has been demanded. In addition, the fact that the conductivity curve shows a J-shaped or U-shaped shape that rises to the right leads to a low resistance value, that is, a relatively high conductivity region, which is relatively narrow.
There is also a need for a reforming method for improving this property.
The present applicant has proposed a method for modifying a composite silicone gel material to which a functional filler is added in addition to the conductive filler as Japanese Patent Application No. 02-116484. Is specifically applied to a conductive silicone gel material. Strictly speaking, the amount of compression displacement is strictly an absolute amount, and the amount of strain is usually a relative amount to the entire length or the entire thickness. Amount is used synonymously.

[0004]

[Technical Matters to be Developed] The present invention has been made in view of the above situation, and the conductivity curve in which the horizontal axis indicates the amount of compressive displacement and the vertical axis indicates the electric resistance value has a J-shaped curve with an upward right. Or U
It is an object of the present invention to provide a method of modifying a conductive silicone gel material that provides stable conductive characteristics that can be more easily used, while providing a method of using the conductive silicone gel material having a character shape.

[0005]

Configuration of the Invention

That is, the method of using the conductive silicone gel material according to the first invention of the present application is a method in which the conductivity curve is plotted by plotting the amount of compressive displacement on the abscissa and the electrical resistance on the ordinate, and the conductivity curve rises to the right. In using a conductive silicone gel material having a U-shape or a U-shape, the conductive silicone gel material is generated such that the small displacement occurs in a curved area near an inflection point having a relatively small displacement and a low resistance value. And a substantially fixed load is applied to utilize the high conductivity and the shock absorbing and vibration-proof properties.

[0006] Further, in the method for modifying a conductive silicone gel material according to the second invention of the present application, a substance having a deactivating effect of a platinum-based catalyst, which is a hydrosilylation catalyst, is provided on at least the surface of a conductive filler. , The gas phase of the substance and / or
Or a step of adsorbing the substance in a liquid phase, a step of adding a conductive filler having the substance adsorbed to the silicone gel stock solution, and an addition reaction of the silicone gel stock solution with the conductive filler added thereto using the platinum-based catalyst. And curing. The present invention aims to achieve the above object.

[0007]

The electric resistance value of the conductive silicone gel material in the curved area near the inflection point of relatively small displacement on the conductive curve showing the upward-sloping J-shape or U-shape has the lowest electric conductivity. In addition, since the applied load for giving this amount of strain is not so large, both the conductivity and the inherent cushioning and vibration-proof properties of the silicone gel as a support function.

[0008] On the surface of the conductive filler adsorbing a substance having a deactivating effect of the platinum-based catalyst, the catalytic action is suppressed, and the silicone gel stock solution is not completely cured, but is in an uncured state. The conductive filler is not restricted by the cured continuous phase of the silicone gel, and maintains a certain degree of freedom. As a result, contact and separation between the conductive fillers become clear.

[0009]

EXAMPLES Specific examples will be described below. First, substances applied to the present invention will be described. First silicone gel is made of a dimethyl siloxane component units, (hereinafter referred to as component A) stock solution serving diorganopolysiloxane silicone gel used in the following formula _{^{[1]: RR 1 2 SiO-}} (R 2 2 SiO) ^{_{n SiR 1 2 R ... [1}} ] [ wherein, R is an alkenyl group, ^{R 1} is a monovalent hydrocarbon group having no aliphatic unsaturated bond, ^{R 2} is a monovalent aliphatic hydrocarbon group (At least 50 mol% of R ²
Is a methyl group, and when it has an alkenyl group, its content is 10 mol% or less), and n is a viscosity of the component at 25 ° C. of 100 to 100,000 cSt.
And a viscosity at 25 ° C. of 50
00 cSt or less, and at least two S
Organohydrogenpolysiloxane (B) which is a stock solution of a silicone gel having a hydrogen atom directly bonded to an i atom
Component), and the ratio (molar ratio) of the total amount of alkenyl groups contained in component A to the total amount of hydrogen atoms directly bonded to Si atoms in component B is 0.1 to 2.2.
An addition reaction type silicone polymer obtained by curing a mixture adjusted to be zero.

The silicone gel will be described in more detail. The component A has a linear molecular structure, and the alkenyl groups R at both ends of the molecule are added to the hydrogen atom directly bonded to the Si atom in the component B. Is a compound capable of forming a cross-linked structure. The alkenyl group present at the molecular terminal is preferably a lower alkenyl group, and a vinyl group is particularly preferable in consideration of reactivity. R ¹ present at the molecular terminal is a monovalent hydrocarbon group having no aliphatic unsaturated bond, and specific examples of such a group include alkyl groups such as a methyl group, a propyl group, and a hexyl group. , A phenyl group and a fluoroalkyl group. In the above formula [1], R ² is a monovalent aliphatic hydrocarbon, and specific examples of such a group include alkyl groups such as methyl group, propyl group and hexyl group, and vinyl groups. Lower alkenyl groups. Provided that at least 50 of R ²
The mol% is a methyl group, and when R ² is an alkenyl group, the alkenyl group is preferably in an amount of 10 mol% or less. When the amount of the alkenyl group exceeds 10 mol%, the crosslinking density becomes too high and the viscosity tends to be high. And n
The viscosity of the component A at 25 ° C. is usually 100 to
100,000 cSt, preferably 200-20,000
It is set to be within the range of cSt.

The component B is a crosslinking agent for the component A,
The hydrogen atom directly bonded to the i atom is added to the alkenyl group in the component A to cure the component A. The B component may have any of the above-mentioned effects, and may have various molecular structures such as a linear, branched chain, cyclic, or network structure. In addition, a hydrogen atom and an organic group are bonded to the Si atom in the B component, and this organic group is usually a lower alkyl group such as a methyl group. further,
The viscosity of the component B at 25 ° C. is usually 5,000 cSt or less, preferably 500 cSt or less. Such B
Examples of the component include an organohydrogenpolysiloxane in which both molecular terminals are blocked with a triorganosiloxy group,
A copolymer of diorganosiloxane and organohydrogensiloxane, tetraorganodisiloxane tetra hydrogen cyclotetrasiloxane, copolymers siloxane consisting of HR ¹ ₂ SiO 1/2 units and SiO 4/2 units, and H
R ¹ ₂ SiO 1/2 units and ^R ₁ 3 SiO 1/2 units and SiO
Copolymer polysiloxane consisting of 4/2 units can be mentioned. However, in the above formula, R ¹ has the same meaning as described above. The ratio of the total molar amount of alkenyl groups in component A to the total molar amount of hydrogen atoms directly bonded to Si in component B is usually 0.1 to 2.0, preferably 0.1. It is manufactured by mixing and curing the component A and the component B so as to fall within the range of 1.0.

The curing reaction in this case is usually carried out using a catalyst. As the catalyst used herein, a platinum-based catalyst is preferable, and examples thereof include finely pulverized elemental platinum,
Examples thereof include chloroplatinic acid, platinum oxide, complex salts of platinum and olefins, platinum alcoholates, and complex salts of chloroplatinic acid and vinyl siloxane acid. Such a complex salt is composed of A component and B component.
It is used in an amount of usually at least 0.1 ppm (amount in terms of platinum, the same applies hereinafter), preferably at least 0.5 ppm, based on the total weight of the components. The upper limit of the amount of such a catalyst is not particularly limited. For example, when the catalyst is in a liquid state or when it can be used as a solution, 200 p.
pm or less is sufficient.

[0013] The above-mentioned A component, B component and catalyst are mixed and left to stand at room temperature or cured by heating to produce the silicone gel used in the present invention. When curing by heating, the heating temperature is usually 50
１６０160 ° C. The silicone gel thus obtained usually has a penetration of 5 to 250 as measured by JIS (K-2207-1980, 50 g load). The hardness of such a silicone gel varies depending on the crosslinked structure formed by the above-mentioned component A and component B. Alternatively, it can be adjusted by previously adding a silicone oil having methyl groups at both ends in an amount within a range of 5 to 75% by weight based on the obtained silicone gel. The silicone gel can be adjusted as described above, or a commercially available silicone gel can be used. Examples of commercially available products that can be used in the present invention include CF5027, TOUGH-2, TOUG
H-3, TOUGH-4, TOUGH-5, TOUGH
-6, TOUGH-7 (manufactured by Toray Dow Corning Silicone), X32-902 / cat1300, KE1
308 / cat1300-L4 (manufactured by Shin-Etsu Chemical Co., Ltd.), F250-121 (manufactured by Nippon Yunika Co., Ltd.) and the like.

In addition, in addition to the above-mentioned components A, B and the catalyst, a pigment, a curing retarder, a flame retardant, a filler and the like can be blended within a range that does not impair the properties of the silicone gel.
In some cases, in order to enhance functions such as vibration isolation and cushioning properties, a silicone gel obtained by mixing fine hollow sphere fillers may be used. (Registered trademark), Expancel (registered trademark) sold by the company, Matsumoto Microsphere (manufactured and sold by Matsumoto Yushi Pharmaceutical Co., Ltd.) and the like.

Next, a conductive filler added for imparting conductivity to the silicone gel will be described.
As the conductive filler, carbon black, carbon fiber, graphite, metal powder, metal oxide, metal flake, metal fiber, etc., in addition to the conductive substance itself, insulating organic and inorganic fine particles such as nickel, cobalt, gold,
Some are plated or coated with a conductive material such as silver. These generally have an arbitrary shape such as a sphere, a scale, and a fiber. In the present invention, among these conductive fillers,
When finished to a conductive silicone gel material, those having a J-shaped or U-shaped conductivity curve which rises to the right can be used singly or as a mixture of two or more. In general, it is desirable that the conductive filler is uniformly distributed in the silicone gel, and it is necessary to take care not to cause precipitation as much as possible. For this purpose, it is desirable to use a glass- or resin-based micro hollow sphere coated with a conductive metal such as silver. If magnetic particles such as nickel are used, for example, not only conductivity can be imparted, but also magnetism can be imparted, so that a magnetically sensitive conductive silicone gel material can be produced. It can be used for such purposes.

Next, the substance used to deactivate the catalyst used in the present invention will be described. This substance may react with the platinum-based catalyst more quickly than the reactive group of the silicone gel, and may form a strong chemical bond between them.
It does not matter whether organic or inorganic. Generally, S,
P, N, Sn, C = C atoms or molecules. Specifically, as the sulfur-based compound, as inorganic compounds, potassium sulfate, ammonium sulfate, ammonium persulfate, sodium persulfate, sodium sulfite, hydrosulfide, sulfate such as hydroxyamine sulfate, sulfur, carbon disulfide, sulfoxylic acid Soda (Rongalit) and the like,
Examples of organic compounds include thioglycolic acid, thioglycolic acid such as butyl thioglycolate, and thioglycolic acid such as butyl thioglycolate and derivatives thereof, mercaptan compounds such as β-mercaptopropionic acid, thioacetic acid, thiourea, and sulfone. And surfactants such as acid salts and sulfates. Further, as the phosphorus compound, as an inorganic compound, phosphoric acid, ammonium phosphate, phosphorous acid, hypophosphorous acid, sodium pyrophosphate, sodium acid metaphosphate,
Phosphoric acid and its salts such as sodium tripolyphosphate,
Examples of the organic phosphorus compound include trimethyl phosphate, dialkyldithiophosphoric acid, and phosphite. Furthermore, tin compounds include various tin chlorides.
There are tin oxides, other examples include rhodan salts and stannous sulfate, and examples of the amine compound include iminobispropylamine, triethylamine, 3-diethylaminopropylamine, tetramethylethylenediamine, and 3-methoxypropylamine. .

The step of adsorbing a substance having a platinum catalyst deactivating effect on at least the surface of the conductive filler may be performed under an atmosphere containing an organic or inorganic compound such as sulfur, phosphorus, a tin compound or an amine. This is performed by leaving the conductive filler to be added, or immersing the conductive filler in an aqueous solution or solvent solution in which the compound is dissolved, and then heating and drying to remove water and the solvent. By performing such a treatment, the substance having a deactivating effect on the platinum-based catalyst adsorbed on the conductive filler selectively reacts with the platinum-based catalyst in the silicone gel stock solution at the conductive filler interface during the curing step. Therefore, even if an uncrosslinked component is still present in the silicone gel phase, the reaction at the interface of the conductive filler is stopped, and the silicone gel as the base material is cured and the cured continuous phase of the gel is formed. Is formed, a layer on which the silicone gel stock solution is not cured is formed on the very surface of the conductive filler dispersed and present. As a result, in the obtained conductive silicone gel material, the conductive filler is not restricted by the cured continuous phase of the silicone gel, maintains a certain degree of freedom, and the contact and separation between the conductive fillers become clear.

Next, specific examples of the conductive silicone gel material will be described, and then, examples of modifying the conductive silicone gel material will be described, and then, how to use these conductive silicone gel materials will be described. Here, as a specific example, a silicone gel is used as a base material by Tore Dow Corning Silicone.
OUGH-2 was adjusted to a penetration of 160 and used when mixing the A component and the B component, and after adding a conductive filler and uniformly stirring, deaerated and separated by a 3 mm spacer. A standard procedure was to pour between glass plates and heat at 70 ° C. for 3 minutes and then at 100 ° C. for 3 hours. Then, the sheet was cut into a disk shape using a punch having a diameter of 25 to obtain each sample. As shown in FIG. 10, an electrode plate F (60 × 70 × 1) silver-plated on a copper plate was obtained.
mm) and pressurized test system S (compression tester MODEL-1310D) manufactured by Aiko Engineering Co., Ltd.
S, controller 1011C, load cell 3200)
While pressing sample X with
Using an 847 multimeter M, a change in electric resistance value was measured. In addition, reading was performed after standing for a certain period of time until the electric resistance value reached equilibrium after pressurization, thereby eliminating a measurement value variation error.

Sample 1 was prepared by adding 35% by weight, based on a silicone gel, of metal microlite Ag CG having a particle diameter of 90 .mu.m, made of silver-coated ceramic hollow spheres manufactured by Showa Denko KK. FIG. 1 shows a conductivity curve of the sample 1 according to the measurement method, in which the amount of compressive displacement is plotted on the horizontal axis and the electrical resistance is plotted on the vertical axis.

Sample 2 was prepared by adding 40 wt% of a metallite Ag SF44 having the same particle diameter of 30 μm to the silicone gel as the base material. FIG. 2 shows the same conductivity curve of Sample 2.

Sample 3 was prepared by adding POG-80 having an average particle diameter of 40 μm, made of artificial graphite powder manufactured by Sumitomo Chemical Co., Ltd., to silicone gel as a base material at 30% by weight. FIG. 3 shows the same conductivity curve of Sample 3.

As a sample 4, Dentol BK-200 having a fiber diameter of 0.2 to 0.5 μm and a fiber length of 10 to 20 μm using a conductive titanium oxide whisker manufactured by Otsuka Chemical Co., Ltd. It was prepared by adding weight%. FIG. 4 shows the same conductivity curve of Sample 4.

A comparison of the conductivity curves of these samples shows that the conductive silicone gel materials containing spherical conductive fillers, such as Sample 1 and Sample 2, showed an increase in the electrical displacement with respect to the increase in the amount of compressive displacement. It can be seen that the conductivity curve in which the resistance value once decreases and then increases, and the conductivity curve in which the amount of compressive displacement is plotted on the horizontal axis and the electric resistance value is plotted on the vertical axis, shows a J-shaped or U-shaped shape rising to the right. Further, the same tendency is observed in the conductive silicone gel material containing a flaky conductive filler such as Sample 3, and the conductive silicone gel material containing a spherical or flaky conductive filler is used. It is confirmed that the conductive properties show a behavior not seen in the conventional conductive rubber. On the other hand, the conductive properties of a conductive silicone gel material containing a fibrous conductive filler such as sample 4 show a tendency that the electrical resistance value monotonously decreases with respect to the amount of compressive displacement, and depending on the conductive filler, the conventional conductive material has a low conductivity. It is confirmed that there is also a conductive silicone gel material showing the same behavior as the conductive rubber.

Further, focusing on the conductive silicone gel material having a J-shape or U-shape rising to the right like Sample 1, Sample 2, and Sample 3, and observing the region having the highest conductivity, It can be seen that the high conductivity region is around the inflection point in the conductivity curve and is relatively narrow. However, as a matter of course, in conductive materials, high and stable conductivity is desired. Therefore, an embodiment of a reforming method for improving this will be described.

In this embodiment, dodecylbenzenesulfonic acid is used as a substance having a deactivation effect of a platinum-based catalyst, and this is adsorbed on a conductive filler. The conductive filler includes metallite Ag SF44 having a particle diameter of 30 μm as a silver-coated ceramic hollow microsphere.
Of 40 to the silicone gel TOUGH-2 as the base material
% By weight. Then, in the adsorption step, 20 g of the conductive filler was added to 500 ml of a 100 ppm aqueous solution of dodecylbenzenesulfonic acid while stirring with a magnetic stirrer, and after stirring for 1 hour, suction filtration was performed using a filter paper, and the mixture was filtered at 70 ° C. for 3 hours. It was decided to dry. Then, a sample 5 having a thickness of 3 mm and a diameter of 25 mm was obtained in the same manner as the sample, and the conductivity curve measured and plotted in the same manner as described above was compared with the conductivity curve of the one prepared by adding an untreated conductive filler. Also shown in FIG.

In another example, octylbenzene acid was used in place of dodecylbenzenesulfonic acid, and all other conditions were the same as in the preparation procedure of sample 5, and sample 6 was used.
I got FIG. 6 shows the same conductivity curve of Sample 6.

Further, sodium octane sulfonate was used, and all other conditions were the same as those for the preparation of sample 5.
Sample 7 was obtained. FIG. 7 shows the same conductivity curve of Sample 7.

Sample 8 was prepared using dimethyl sulfoxide and all other conditions were the same as those for preparing sample 5.
I got FIG. 8 shows the same conductivity curve of Sample 8.

A sample 9 was obtained using sodium oleate under the same conditions as in the preparation of the sample 5 except for all the other conditions. The same conductivity curve of Sample 9 is shown in FIG.

As can be seen from these conductivity curves, as compared with the conductive silicone gel material prepared using the untreated conductive filler, the one prepared by the modification treatment has a low resistance region. It spreads and exhibits a low resistance value up to a relatively large amount of compressive displacement, making it easier to use as a conductive silicone gel material. The modified conductive silicone gel material was torn at room temperature, and the fracture surface was observed using a scanning microscope. As a result, the conductive silicone gel material adjusted using an untreated conductive filler was used. In contrast, the conductive filler surface is covered with silicone gel, whereas the conductive silicone gel material prepared using the modified conductive filler clearly shows the shape of the conductive filler, and the degree of freedom of the conductive filler Was confirmed visually. In addition, it is thought that improvement can be achieved by improving the wettability of the conductive filler instead of this modification method, and various coupling agents were tried. The physical properties were reduced, and a satisfactory conductive silicone gel material was not obtained. The effect of the present modification method was further confirmed. Further, according to the present modification method, the problem that the conductive properties vary greatly depending on the method of mixing the silicone gel and the conductive filler, the stirring intensity, the time, and the like is solved, and a more stable product can be obtained. Was.

Next, a method of using a conductive silicone gel material having a J-shaped or U-shaped conductive curve having an upwardly-sloping conductive curve will be described. First, a description will be given of an example of use in which a change in the electric resistance value during this period is sensed in a downward-sloping curve area where the resistance value changes from a high resistance value to a low resistance value with a relatively small displacement from a compression displacement amount of 0. FIG. 11 shows a clamper used for fingers of a working robot.
The clamping pieces 1, 1 of which are controlled to be opened and closed by the drive section 12, can handle eggs, cakes, tomatoes and the like which are extremely easily broken. Pressure-sensitive fingers 2, 2 are attached to the inside of the holding pieces 1, 1, and the pressure-sensitive fingers 2, 2 are soft and have a large frictional outer skin 2.
1 is an outer shell, and has a structure in which conductive metal foils 22, 22 on the front and back are sandwiched in the outer skin 21 of the sheet-shaped piece 3 of the conductive silicone gel material having the above-mentioned conductivity curve. In addition, the lead wire 23 from this conductive metal foil 22
Is extended to a control unit (not shown) so that the sheet-like piece 3
Is detected as an electric signal, and the clamping force and the movement of the clamping pieces 1 and 1 are controlled by the signal. In this use example, a circuit is configured to stop the clamping operation of the holding pieces 1 and 1 at a change in which the conductivity becomes highest from the high resistance value of the compression displacement amount 0, and the holding pieces 1 and 1
The object to be grasped is grasped so as not to drop. Here, the penetration of the silicone gel as the substrate is, for example, 100 to 200.
By using a material prepared to a certain degree, this change in the electric resistance value of the conductive silicone gel material is extremely prominent, and the conductive silicone gel material itself is flexible,
Clamp what easily breaks well.

Next, in the curved area near the inflection point of relatively small displacement, a substantially fixed load is applied to the conductive silicone gel material so that the small displacement occurs, and the conductivity and the cushioning are applied. A description will be given of an embodiment using the vibration proof property. FIG. 12 is an application to a primitive electric circuit for easy understanding, and is a main part of a tuning circuit using a pulley type reduction dial in a short-wave radio or the like. In the figure, 4 is a variable condenser, 42 is a reduction pulley fixed to the variable condenser shaft 41, 5 is a knob shaft, 51 is a flywheel fixed to the rear end of the knob shaft 5, and 52 is a reduction pulley 42
And a belt wound around the knob shaft 5. Reference numeral 6 denotes a conductive sheet which is a conductive silicone gel material having the above-mentioned conductivity curve, one surface of which is directly adhered to a metal chassis B, and the other side of which is directly mounted with a variable condenser 4. Reference numeral 71 denotes a screw, 72 denotes a coil spring, and 73 denotes a washer. While the screw 71 is screwed into the chassis B, the conductive sheet 6 is appropriately distorted.
The variable condenser 4 is fixed to a predetermined position of the chassis B. Here, the moderate strain on the conductive sheet 6 is the amount of strain at the inflection point in the conductivity curve, which is the lowest in the electric resistance value. Therefore, the weight of the variable condenser 4 and the strength of the coil spring 72 are high. The thickness and area of the conductive sheet 6 are determined in consideration of the degree of screwing of the screw 71 and the like. For this reason, one electrode plate of the variable condenser 4 is grounded to the chassis B as it is, and at the same time, the entire variable condenser 4 is supported by the conductive silicone gel material in a shock-absorbing and vibration-proof manner. Even if vibration occurs, this shock,
The vibration is not transmitted to the variable condenser 4 and no electric noise is generated. This kind of usage is different from this tuning circuit,
It can be effectively applied to so-called radio waves, particularly high frequency input / output portions, such as oscillation circuits.

Subsequently, in the curve region rising to the right where a relatively large displacement changes to a high resistance value from the vicinity of the inflection point of a relatively small displacement, the conductive silicone gel material is applied so that the small displacement is generated. A description will be given of a usage example in which a load is applied and a change in the electric resistance value due to a further load is sensed. FIG. 13 shows a so-called punching measuring device. In this example, a floor 81 as a base,
The main body includes a series of pillars 82 and a ceiling 83, a punching ball P, a pressure-sensitive measuring unit 9, a display unit 85, and a calculation unit (not shown). The punching ball P is hung by a chain 84 at the tip of the ceiling part 83, and a pressure-sensitive measuring unit 9 is provided behind the ceiling part 83, which corresponds to this rotation trajectory. The pressure-sensitive measuring section 9 fits a pressure-receiving plate 91 into a window opened in a ceiling portion 83, and a conductive sheet 92, which is a conductive silicone gel material having the above-described conductivity curve, and a pressing plate 93 from above. The pressing plate 93 is overlaid and the bolts 94, 94 thereabove.
, The downward pressing force is adjusted.
A conductive metal foil 95 is attached to the inside of the pressing plate 93, and the lead wire from the conductive metal foil 95 is extended to the calculation unit, and the calculation result is displayed on the display unit 85 on the front of the column unit 82. Posted by lightning. Then, when the punching ball P is hit hard, the punching ball P collides with the pressure receiving plate 91 of the pressure-sensitive measuring unit 9 while being bound by the chain 84 and drawing a circle.
Further, the upper conductive sheet 92 is distorted. The conductive sheet 92 has been given a predetermined initial load by the bolt 94 from above and has a low electric resistance value, and is distorted by a further load to have a high electric resistance value. The electric resistance changes and the electric resistance is converted into a punching force and displayed.

[0034]

As described above, according to the present invention, there is provided a method of utilizing a conductive silicone gel material exhibiting a unique behavior such as a J-shaped or U-shaped conductivity curve having an upwardly-sloping conductivity curve. Shock-absorbing, anti-vibration, easy-to-deform
Easy moldability, which does not require kneading or high-temperature heating, can be utilized as the conductive silicone gel material, and its use is expanded. In addition, a low resistance value, that is, a region with high conductivity is expanded, and the dispersion of the conductive characteristics due to the mixing method of the stock solution, the intensity of stirring, time, etc. is reduced, so that a more easily usable conductive silicone gel material can be obtained. , And more applications can be expected.

[Brief description of the drawings]

FIG. 1 is a conductivity curve in which the amount of compressive displacement of a conductive silicone gel material prepared by adding 35% by weight of metallite Ag CG is plotted on the abscissa and the electrical resistance is plotted on the ordinate.

FIG. 2 is the same conductivity curve of a conductive silicone gel material prepared by adding 40% by weight of metallite Ag SF44.

FIG. 3 is the same conductivity curve of a conductive silicone gel material prepared by adding 30% by weight of artificial graphite powder POG-80.

FIG. 4 is the same conductivity curve of a conductive silicone gel material prepared by adding 30% by weight of Dentol BK-200.

FIG. 5 is the same conductivity curve of a conductive silicone gel material prepared by adding 40% by weight of metallite Ag SF12 adsorbed with dodecylbenzenesulfonic acid.

FIG. 6 is the same conductivity curve of a conductive silicone gel material prepared by performing adsorption treatment using octylbenzene acid.

FIG. 7 is the same conductivity curve of a conductive silicone gel material prepared by adsorption treatment using sodium octane sulfonate.

FIG. 8 is the same conductivity curve of a conductive silicone gel material prepared by performing adsorption treatment using dimethyl sulfoxide.

FIG. 9 is the same conductivity curve of a conductive silicone gel material prepared by adsorption treatment using sodium oleate.

FIG. 10 is a schematic diagram showing a state of measuring an electric resistance value for obtaining a conductivity curve.

FIG. 11 is an example of use in which a change in electric resistance in a curved area falling to the right from a compression displacement amount of 0 to a relatively small displacement is sensed, and a partially enlarged cross section of a clamper used for a finger of a work robot; FIG.

FIG. 12 is an embodiment in which a substantially fixed load corresponding to a curved area near the inflection point is applied, and the conductivity and the damping and vibration damping properties are used, and a pulley type in a short wave radio or the like. It is a perspective view of the principal part of the tuning circuit by a speed reduction dial.

FIG. 13 shows that a load corresponding to the vicinity of an inflection point is given in advance in a curve region which rises to the right with a relatively large displacement from the vicinity of the inflection point, and a change in the electric resistance value due to a further applied load is sensed. FIG. 6 is a side view including a partial cross section of a punching measuring device, showing an example of use.

[Explanation of symbols]

 Reference Signs List A clamper B chassis P punching ball F electrode plate S pressure test system M multimeter X sample 1 sandwiching piece 12 drive unit 2 pressure-sensitive finger 21 outer skin 22 conductive metal foil 23 lead wire 3 conductive silicone gel material sheet Piece 4 variable condenser 41 variable condenser shaft 42 deceleration pulley 5 knob shaft 51 flywheel 52 belt 6 conductive sheet as conductive silicone gel material 71 screw 72 coil spring 73 washer 81 floor 82 column 83 83 ceiling 84 chain 85 display 9 pressure-sensitive Measuring unit 91 Pressure receiving plate 92 Conductive sheet 93 Pressing plate 94 Bolt 95 Conductive metal foil

──────────────────────────────────────────────────の Continuation of the front page (51) Int.Cl. ⁷ identification code FI H05K 9/00 H05K 9/00 X // C08G77 / 04 C08G77 / 04 (58) Field surveyed (Int.Cl. ⁷ , (DB name) H01B 1/24 C08K 9/00 C08L 83/05 C08L 83/07 H01C 10/10 H05K 9/00 C08G 77/04

Claims (2)

(57) [Claims] When using a conductive silicone gel material having a J-shaped or U-shaped conductive curve in which the amount of compressive displacement is plotted on the abscissa and the electrical resistance is plotted on the ordinate, the displacement is relatively small. In the curved area near the inflection point where the resistance is low, the conductive silicone gel material is
By applying a nearly fixed load, its high conductivity and cushioning
A method of using a conductive silicone gel material characterized by utilizing vibration characteristics. 2. A step of previously adsorbing a substance having a deactivating effect on a platinum-based catalyst as a hydrosilylation catalyst in at least a surface of the conductive filler in a gas phase and / or a liquid phase of the substance. A step of adding a conductive filler to which a substance is adsorbed to a silicone gel stock solution, and a step of subjecting the silicone gel stock solution to which the conductive filler is added to an addition reaction using the platinum-based catalyst to cure the silicone gel stock solution. A method for modifying a conductive silicone gel material.