Electrically conductive paste

Abstract

The invention relates to an electrically conductive paste comprising an elastic binder (A) and a conductive filler (B), the conductive filler (B) comprising the following components: at least one conductive filler (B1) in bead form, at least one conductive filler (B2) in flake form and at least one conductive filler (B3) in tube form.

Description

Electrically conductive paste Field of the Invention The present disclosure generally relates to an electrically conductive paste comprising an elastic binder (A) and a conductive filler (B). The present disclosure further relates to a process for producing the conductive paste and also to the use thereof for application to elastomeric substrates. Background Electrically conductive pastes for forming conductive structures are known in the art and generally comprise a binder filled with metallic, metallized, or carbon particles. A disadvantage of these pastes is that usually they have only little or no extensibility. Description In an aspect, the present disclosure provides a conductive paste which enables a high conductivity even at low fill levels and hence allows a high extensibility. In this regard, an electrically conductive paste is provided comprising an elastic binder (A) and a conductive filler (B), wherein the conductive filler (B) comprises the following components: at least one conductive spherical filler (B1), at least one conductive platelet-shaped filler (B2), and at least one conductive rodletlike filler (B3). Surprisingly it has been found in accordance with the present disclosure that the specific combination of an elastic binder (A) and a conductive filler (B) comprising at least one spherical filler (B1), at least one platelet-shaped filler (B2), and at least one rodletlike filler (B3) allows a conductive paste to be provided which exhibits high conductivity even at low fill levels and in association therewith has a high extensibility. Without being tied to a mechanism, it is thought that this is possible as a result of the following mechanism: The platelet-shaped filler (B2) because of its high surface area is able to form conductive "islands" which permit a high conductivity in all spatial directions. The rodletlike filler (B3) because of its elongate structure enables the formation of conducting bridges between these islands, so forming a conducting three-dimensional network in the binder matrix. As a result, the fraction of conductive filler (B) can be kept low, and this enables high extensibility of the paste. The spherical filler (B1) is able to take up position at the surface of the platelet-shaped filler (B2) and of the rodletlike filler (B3) and by virtue of its morphology is able to close vacancies in the binder. This leads to an increase in the contact points of the fillers overall and hence in the number of conducting paths within the network. The spherical filler (B1) is able to take up position individually or as an agglomerate and also to occupy vacancies in the binder. This has the advantage that it is less of a disruption in the event of deformation. Because of the high number of contact points, the paste can also be deformed after drying without loss of the conductivity. Consequently, the network made up of the three different types of fillers has a special structure which enables it, in the event of deformation of the binder, to adapt to the movement without losing its conductivity. A spherical filler (B1) is understood in the present disclosure to refer to particulates which have approximately a sphere shape. The term is also intended to comprehend particles having an irregular, nonideal sphere shape. In one preferred embodiment of the present disclosure, the spherical filler (B1) has a mean particle diameter, measured according to ISO 21501-2:2019-11 (light scattering liquid-borne particle counter), of at most 200 µm, preferably of 0.02 µm to 200 μm, more preferably of at most 100 μm, as for example of 0.02 μm to 100 μm, more preferably of 0.02 <semantics>μ<annotation encoding="application / x-tex">\mu< / annotation>< / semantics>m to 50 <semantics>μ<annotation encoding="application / x-tex">\mu< / annotation>< / semantics>m, and more particularly of 0.02 <semantics>μ<annotation encoding="application / x-tex">\mu< / annotation>< / semantics>m to 10 <semantics>μ<annotation encoding="application / x-tex">\mu< / annotation>< / semantics>m. If the mean particle diameter is too great, then a high fill level is needed in order to obtain good conductivity. Moreover, particles that are too large are unable to penetrate small vacancies in the conduction paths. If the mean particle diameter is too small, it is unable to bind well into the polymer matrix. The spherical filler (B1) preferably comprises materials selected from the group consisting of metals, more particularly transition metals, alkali and alkaline earth metals and salts thereof, metallized glass, metallized ceramic, carbon, and mixtures thereof. Carbon particles are particularly preferred. The spherical filler (B1) may comprise the aforesaid materials and preferably carbon, more particularly in a fraction of more than 90 wt%, more particularly of more than 95 wt%. The fraction of the spherical filler (B1), based on the total weight of the conductive paste, may be from 0.1 to 50 wt%, more preferably from 1 to 15 wt%, more preferably from 1 to 10 wt%, more preferably from 1 to 8 wt%, and more particularly from 1 to 5 wt%. A platelet-shaped filler (B2) is understood in the present disclosure to refer to substantially flat particulate fillers. This term is intended more particularly to comprehend flat fillers having an aspect ratio of at least 1 / 10 and less than 1 / 106. The platelet-shaped filler (B2) may also have a laminar disposition. In one preferred embodiment of the present disclosure, the platelet-shaped filler (B2) has a mean particle size, measured according to ISO 21501-2:2019-11 (light scattering liquid-borne particle counter), of at most 150 µm, as for example of 0.02 to 150 μm, more preferably of at most 100 μm, as for example of 2 μm to 100 μm, and more particularly of 5 to 80 µm. With these particle sizes, and more particularly at a particle size (B2) of 5 µm to 80 µm, the extensibility of the coating is particularly good. If the mean particle size is too great, a high fill level is necessary in order to obtain good conductivity. The platelet-shaped filler (B2) preferably comprises materials selected from the group consisting of metals, more particularly transition metals, more particularly metallized glass, metallized ceramic, carbon, and mixtures thereof. The platelet-shaped filler may comprise the aforesaid materials and, in particular, metallized glass, preferably in a fraction of more than 75 wt%, more particularly more than 95 wt%. Particularly preferred are platelet-shaped carbon particles and / or metallized glass. For carbon-based platelet-shaped fillers (B2), more particularly for platelet-shaped carbon particles, preferred mean particle sizes are at most 2 µm, as for example 2 μm to 0.01 μm, and more particularly at most 0.8 μm, as for example from 0.8 μm to 0.02 µm, measured according to ISO 21501-2:2019-11 (light scattering liquid- borne particle counter). The fraction of the platelet-shaped filler (B2), based on the total weight of the conductive paste, may be from 0.5 to 50 wt%, more preferably from 5 to 40 wt%, and more particularly from 10 to 25 wt%. A rodlet-shaped filler (B3) refers to a filler composed of particles which are long in relation to its diameter. The surface of the platelet-shaped filler may have vacancies, elevations, depressions, or be substantially smooth. Also conceivable are branched, branch-shaped, bent, ramified rodlet shapes. In one preferred embodiment of the present disclosure, the rodlet-shaped filler (B3) has a mean aspect ratio of at least 0.1, as for example of 1 / 10 to 1 / 108, and more particularly of at least from 102 to 108. If the mean aspect ratio is too great, a high fill level is necessary in order to achieve good conductivity. The rodlet-shaped filler (B3) preferably comprises materials selected from the group consisting of metals, more particularly transition metals, metallized glass, carbon, more particularly single-layer, preferably graphenelike, and also multilayer carbon nanotubes, and mixtures thereof. The rodlet-shaped filler may comprise the aforesaid materials and more particularly carbon nanotubes preferably in a fraction of more than 90 wt%, more particularly of more than 95 wt%. The fraction of the rodlet-shaped filler (B3), based on the total weight of the conductive paste, is preferably from 0.01 to 10 wt%, more preferably from 0.01 to 5 wt%, and more particularly from 0.1 to 3 wt%. In one preferred embodiment, the fraction of the filler (B), based on the total weight of the conductive paste, is from 0.03 wt% to 30 wt%, more preferably 0.03 wt% to 25 wt%, and more particularly 0.03 wt% to 20 wt%. The filler (B) may be distributed uniformly in the conductive paste. The uniform distribution of the filler is determined by optical evaluation (electron microscope). If the fraction of agglomerates in an area of 1 mm2 is below 20% of the filler fraction, the distribution present is uniform. An elastic binder (A) is understood in the present disclosure to refer to a binder which is capable of changing its shape on exposure to force and returning substantially to its original shape on cessation of the active force. The binder (A) preferably has an extension, measured according to standard ISO 527 (2018-06-29), of at least 100%, as for example of 100 to 700%, more preferably at least 200%, as for example 200 to 700%, and more particularly of at least 300, as for example 300 to 700%. The fraction of the binder (A), based on the total weight of the conductive paste, may be from 50 wt% to 99 wt%, more preferably from 60 wt% to 80 wt%, and more particularly from 65 wt% to 80 wt%. In a further preferred embodiment, the elastic binder (A) comprises thermoplastic elastomers preferably selected from the group consisting of silicones, urethanes, epoxies, amides, esters, or mixtures thereof. In a further preferred embodiment, the elastic binder (A) is not conductive. In this embodiment the elastic binder (A) comprises preferably binders selected from the group of the polyurethanes, silicones, fluorosilicones, polycarbonates, ethyl-vinyl acetates (EVA), acrylonitrile-butadiene-styrene (ABS), acrylates, polyvinyl chlorides (PVC), polyphenyl ethers, polystyrene, polyamides, nylon, polyolefins, polybutyl terephthalates (PBT), polyethylene terephthalates (PET), fluoropolymers, rubber, more particularly NR (natural rubber), BR (butadiene rubber), IR (isoprene rubber), SBR (styrene-butadiene rubber), CR (chloroprene rubber), BIIR (isobutene-isoprene rubber), CM (chloro rubber), EP(D)M (ethylene-propylene-diene rubber), EU, NBR (nitrile-butadiene rubber), IIR (butyl rubber), CIIR (chlorinated butyl rubber), CSM (chlorosulfonated ethylene rubber), AU (polyurethane rubber), ECO (epichlorohydrin rubber), HNBR (hydrogenated nitrile-butadiene rubber), ACM (acrylate rubber), FKM (fluoro rubber), VMQ (silicone rubber), EAM = AEM (ethylene-acrylate rubber), FFKM perfluoro rubber, TFE+PFVE copolymer of tetrafluoroethylene and perfluoroalkyl vinyl ether, FVMQ (poly-trifluoropropyl vinyl methyl siloxanes), EVA (ethylene-vinyl acetate rubber), polyesters, acetals, polymethyl acrylates, their copolymers, and blends. The fraction of the aforesaid binders in the binder (A) is preferably more than 50 wt%, as for example from 50 wt% to 100 wt%. In one preferred embodiment of the present disclosure the conductive paste has an extensibility of at least 30%, as for example of 30% to 400%, more preferably of at least 40%, as for example of 40% to 300%, and more particularly of at least 60%, as for example of 80% to 150%, measured according to Standard EN ISO 527-1 (Feb. 2012). The conductive paste may be applied to substrates, more particularly elastomeric substrates. Preferred substrates are rubbers, as these themselves possess elastic properties, or are extensible. Preferred types of rubber are as follows: NR (natural rubber), BR (butadiene rubber), IR (isoprene rubber), SBR (styrene-butadiene rubber), CR (chloroprene rubber), BIIR (isobutene-isoprene rubber), CM (chloro rubber), EP(D)M (ethylene-propylene-diene rubber), EU, NBR (nitrile-butadiene rubber), IIR (butyl rubber), CIIR (chlorinated butyl rubber), CSM (chlorosulfonated ethylene rubber), AU (polyurethane rubber), ECO (epichlorohydrin rubber), HNBR (hydrogenated nitrile-butadiene rubber), ACM (acrylate rubber), FKM (fluoro rubber), VMQ (silicone rubber), EAM = AEM (ethylene-acrylate rubber), FFKM perfluoro rubber, TFE+PFVE copolymer of tetrafluoroethylene and perfluoroalkyl vinyl ether, and / or FVMQ (poly-trifluoropropyl vinyl methyl siloxanes). One preferred embodiment comprises the use of the conductive paste for application to elastomeric substrates. The conductive paste in accordance with the present disclosure may be produced for example by a process comprising the following process steps: A) a dispersion comprising an elastic binder (A) is produced or provided; B) a conductive filler (B) is introduced into the dispersion, the conductive filler (B) comprising the following components: at least one conductive spherical filler (B1), at least one conductive platelet-shaped filler (B2), and at least one conductive rodletlike filler (B3). With regard to the conductive paste, the elastic binder (A), the conductive filler (B), the conductive spherical filler (B1), the at least one conductive platelet-shaped filler (B2) and / or the conductive rodletlike filler (B3), and more particularly to their preferred embodiments, the statements in the present text are valid mutatis mutandis. The dispersion in step A) is produced preferably by dispersing of the elastic binder (A) in water or a solvent, as for example alkanes, alcohols, acids, ethers, esters, aromatics, heteroaromatics, halogenated solvents, water, and mixtures thereof. The dispersing takes place preferably in a mixing assembly, e.g., a Speedmixer. The conductive filler (B) is introduced into the dispersion in step B) preferably through a mixing operation, as for example by static and dynamic mixing systems. These may be assisted by ultrasound mixing operations. A further subject of the present disclosure is the use of the paste for producing conductive structures, as for example sensors or actuators. For these, conductive and extensible surfaces are of particular interest, since conductivity and extension are required equally for these applications. The present disclosure is elucidated in more detail below with a number of examples. Example 1: Production of a conductive paste of the present disclosure (recipe paste B) An Impranil DLU dispersion (60 wt% solids fraction polyurethane in water, binder A) is weighed out (11 g) into a Speedmixer canister appropriate for the batch size. Subsequently the components of the filler (B) are added, beginning with the dispersed fillers (Rhenofit® CNT (filler B3), 5.5 g) and C-Sperse® or Birla Conductex SC Ultra® (filler B1), 1.49 g)), and then the solid filler (eConduct Cu or eConduct Glass (filler B2), 1.75 g)) and are combined roughly with a wooden spatula. The mixture is mixed in the Speedmixer at 2300 rpm for 1 minute, stirred with a wooden spatula, and then mixed again in the Speedmixer (1 minute at 2300 rpm). Following application to an elastomer (TPU film), the paste is dried at 60°C for 2 h. This gives the paste B. The electrical resistance is measured via a four-point measurement on the cured paste (B). The result obtained is a value of 860 [<semantics>Ω<annotation encoding="application / x-tex">\Omega< / annotation>< / semantics>], which is very low for the low filler fraction. In order to produce the aforementioned Birla Conductex SC Ultra carbon dispersions, 89 wt% of water are placed in a Speedmixer canister, 1% of technical sodium dodecylbenzenesulfonate is added, and the mixture is premixed in the Speedmixer at 2300 rpm for 15 sec. The result obtained is the paste B of the present disclosure. The electrical resistance is measured via a four-point measurement on the cured paste (B). The result obtained is a value of 860 [<semantics>Ω<annotation encoding="application / x-tex">\Omega< / annotation>< / semantics>]. The carbon powder for dispersion is then weighed out in one go and mixing takes place again in the Speedmixer. Thereafter the dispersion before each use is reagitated with a spatula and reagitated in the Speedmixer (1 min. at 2300 rpm). Example 2: Production of multiple conductive pastes of the present disclosure (A, C, D, E) and of comparative pastes (F, G, H) In analogy to the process described in example 1, the pastes of the present disclosure (A, C, D, E) and the pastes not of the present disclosure (F, G, H) are produced. The proportions used are illustrated in the table below. [Image disponible dans le document PDF, Image available in the PDF document] [Image disponible dans le document PDF, Image available in the PDF document] Tab.1 The fillers stated in the table above are each dispersed in Impranil DLU. The recipes are reported based on wt% in 100 g of Impranil DLU dispersion. Example 3: Determination of the electrical resistance of the pastes of the present disclosure and of the comparative pastes The electrical resistance of the pastes of the present disclosure and of the comparative pastes is determined by means of a four-point measurement. The results are set out in the table below. [Image disponible dans le document PDF, Image available in the PDF document] Tab. 2 As is apparent from the table shown above, the pastes of the present disclosure exhibit much lower resistances than the comparative pastes not of the present disclosure. This is particularly remarkable because the pastes of the present disclosure, on account of the low degree of filler, have extensibilities comparative with those of the pastes not of the present disclosure. Furthermore, the low resistances are remarkable because typically substantially more filler is necessary for such resistances. Where reference is made in the present text to a standard, the standard applicable, unless otherwise indicated, is that valid in each case on the filing date. The present disclosure is described with reference to various embodiments and features, which are non-limiting examples. Some of these embodiments and features are described as being preferable and / or advantageous. However, this is not limiting in any way. These "preferable" or "advantageous" embodiments and features are non-limiting and are provided only as examples. Furthermore, descriptions of embodiments and features as being preferable, or similar, are intended to mean that they may be preferable in at least one embodiment, and not necessarily that they are generally preferable over other embodiments and features. In addition, any references in this disclosure to any prior art or other document or information does not constitute an admission that such art or information was well known or forms part of the common general knowledge in the field, and it does not constitute an admission that any such art or information is relevant to the patentability of the present claims.

Claims

<pat:ClaimStatement>Claims< / pat:ClaimStatement> <pat:Claims com:id="claims"> <pat:Claim com:id="CLM-00001"> <pat:ClaimNumber>1< / pat:ClaimNumber> <pat:ClaimText>1. An electrically conductive paste comprising an elastic binder and a conductive filler, wherein the conductive filler comprises the following components: at least one conductive spherical filler, at least one conductive platelet-shaped filler, and at least one conductive rodlet-shaped filler, wherein the electrically conductive paste is applied on an elastomeric substrate. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00002"> <pat:ClaimNumber>2< / pat:ClaimNumber> <pat:ClaimText>2. The electrically conductive paste of claim 1, wherein the spherical filler has a mean particle diameter, measured according to ISO 21501-2:2019-11, of at most 200 µm. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00003"> <pat:ClaimNumber>3< / pat:ClaimNumber> <pat:ClaimText>3. The electrically conductive paste of claim 2, wherein the mean particle diameter is between 0.02 µm to 200 µm. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00004"> <pat:ClaimNumber>4< / pat:ClaimNumber> <pat:ClaimText>4. The electrically conductive paste of claim 2, wherein the mean particle diameter is at most 100 µm. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00005"> <pat:ClaimNumber>5< / pat:ClaimNumber> <pat:ClaimText>5. The electrically conductive paste of claim 2, wherein the mean particle diameter is between 0.02 µm to 100 µm. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00006"> <pat:ClaimNumber>6< / pat:ClaimNumber> <pat:ClaimText>6. The electrically conductive paste of claim 2, wherein the mean particle diameter is between 0.02 µm to 50 µm. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00007"> <pat:ClaimNumber>7< / pat:ClaimNumber> <pat:ClaimText>7. The electrically conductive paste of claim 2, wherein the mean particle diameter is between 0.02 µm to 10 µm. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00008"> <pat:ClaimNumber>8< / pat:ClaimNumber> <pat:ClaimText>8. The electrically conductive paste of any one of claims 1 to 7, wherein the percentage of the spherical filler, based on the total weight of the conductive paste, is from 0.1 to 50 wt%. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00009"> <pat:ClaimNumber>9< / pat:ClaimNumber> <pat:ClaimText>9. The electrically conductive paste of claim 8, the percentage of the spherical filler, based on the total weight of the conductive paste, is from 1 to 15 wt%. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00010"> <pat:ClaimNumber>10< / pat:ClaimNumber> <pat:ClaimText>10. The electrically conductive paste of claim 8, the percentage of the spherical filler, based on the total weight of the conductive paste, is from 1 to 10 wt%. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00011"> <pat:ClaimNumber>11< / pat:ClaimNumber> <pat:ClaimText>11. The electrically conductive paste of claim 8, the percentage of the spherical filler, based on the total weight of the conductive paste, is from 1 to 8 wt%. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00012"> <pat:ClaimNumber>12< / pat:ClaimNumber> <pat:ClaimText>12. The electrically conductive paste of claim 8, the percentage of the spherical filler, based on the total weight of the conductive paste, is from 1 to 5 wt%. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00013"> <pat:ClaimNumber>13< / pat:ClaimNumber> <pat:ClaimText>13. The electrically conductive paste of any one of claims 1-12, wherein the aspect ratio of the platelet-shaped filler is at least 1 / 10 and less than 1 / 106. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00014"> <pat:ClaimNumber>14< / pat:ClaimNumber> <pat:ClaimText>14. The electrically conductive paste of any one of claims 1-13, wherein the platelet-shaped filler has a mean particle size - ISO 21501-2:2019-11 – of at most 150 µm. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00015"> <pat:ClaimNumber>15< / pat:ClaimNumber> <pat:ClaimText>15. The electrically conductive paste of claim 14, wherein the platelet-shaped filler has a mean particle size of <semantics>0.02<annotation encoding="application / x-tex">0.02< / annotation>< / semantics> to <semantics>150μm<annotation encoding="application / x-tex">150 \mu m< / annotation>< / semantics>. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00016"> <pat:ClaimNumber>16< / pat:ClaimNumber> <pat:ClaimText>16. The electrically conductive paste of claim 14, wherein the platelet-shaped filler has a mean particle size of at most 100 µm. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00017"> <pat:ClaimNumber>17< / pat:ClaimNumber> <pat:ClaimText>17. The electrically conductive paste of claim 14, wherein the platelet-shaped filler has a mean particle size of 2 µm to 100 µm. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00018"> <pat:ClaimNumber>18< / pat:ClaimNumber> <pat:ClaimText>18. The electrically conductive paste of claim 14, wherein the platelet-shaped filler has a mean particle size of 5 to 80 µm. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00019"> <pat:ClaimNumber>19< / pat:ClaimNumber> <pat:ClaimText>19. The electrically conductive paste of any one of claims 1-18, wherein the percentage of the platelet-shaped filler, based on the total weight of the conductive paste, is from 0.5 to 50 wt%. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00020"> <pat:ClaimNumber>20< / pat:ClaimNumber> <pat:ClaimText>20. The electrically conductive paste of any one of claims 1-18, wherein the percentage of the platelet-shaped filler is from 5 to 40 wt%. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00021"> <pat:ClaimNumber>21< / pat:ClaimNumber> <pat:ClaimText>21. The electrically conductive paste of any one of claims 1-18, wherein the percentage of the platelet-shaped filler is from 10 to 25 wt%. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00022"> <pat:ClaimNumber>22< / pat:ClaimNumber> <pat:ClaimText>22. The electrically conductive paste of any one of claims 1-21, wherein the rodlet- shaped filler has a mean aspect ratio of at least 0.

1. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00023"> <pat:ClaimNumber>23< / pat:ClaimNumber> <pat:ClaimText>23. The electrically conductive paste of claim 22, wherein the rodlet-shaped filler has a mean aspect ratio of 1 / 10 to 1 / 108. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00024"> <pat:ClaimNumber>24< / pat:ClaimNumber> <pat:ClaimText>24. The electrically conductive paste of claim 22, wherein the rodlet-shaped filler has a mean aspect ratio of 102 to 108. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00025"> <pat:ClaimNumber>25< / pat:ClaimNumber> <pat:ClaimText>25. The electrically conductive paste of any one of claims 1-24, wherein the percentage of the rodlet-shaped filler, based on the total weight of the conductive paste, is from 0.01 to 10 wt%. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00026"> <pat:ClaimNumber>26< / pat:ClaimNumber> <pat:ClaimText>26. The electrically conductive paste of claim 25, wherein the percentage of the rodlet-shaped filler is from 0.01 to 5 wt%. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00027"> <pat:ClaimNumber>27< / pat:ClaimNumber> <pat:ClaimText>27. The electrically conductive paste of claim 25, wherein the percentage of the rodlet-shaped filler is from 0.1 to 3 wt%. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00028"> <pat:ClaimNumber>28< / pat:ClaimNumber> <pat:ClaimText>28. The electrically conductive paste of any one of claims 1-7, wherein the percentage of the conductive filler, based on the total weight of the conductive paste, is from 0.03 wt% to 30 wt%. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00029"> <pat:ClaimNumber>29< / pat:ClaimNumber> <pat:ClaimText>29. The electrically conductive paste of claims 28, wherein the percentage of the conductive filler is from 0.03 wt% to 25 wt%. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00030"> <pat:ClaimNumber>30< / pat:ClaimNumber> <pat:ClaimText>30. The electrically conductive paste of claims 28, wherein the percentage of the conductive filler is from 0.03 wt% to 20 wt%. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00031"> <pat:ClaimNumber>31< / pat:ClaimNumber> <pat:ClaimText>31. The electrically conductive paste of any one of claims 1-30, wherein the percentage of the binder, based on the total weight of the conductive paste, is from 50 wt% to 99 wt%. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00032"> <pat:ClaimNumber>32< / pat:ClaimNumber> <pat:ClaimText>32. The electrically conductive paste of claim 31, wherein the percentage of the binder is from 60 wt% to 80 wt%. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00033"> <pat:ClaimNumber>33< / pat:ClaimNumber> <pat:ClaimText>33. The electrically conductive paste of claim 31, wherein the percentage of the binder is from 65 wt% to 80 wt%. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00034"> <pat:ClaimNumber>34< / pat:ClaimNumber> <pat:ClaimText>34. The electrically conductive paste of any one of claims 1-33, wherein the elastic binder comprises thermoplastic elastomers. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00035"> <pat:ClaimNumber>35< / pat:ClaimNumber> <pat:ClaimText>35. The electrically conductive paste of claim 34, wherein the thermoplastic elastomers are selected from the group consisting of silicones, urethanes, epoxies, amides, esters, and mixtures thereof. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00036"> <pat:ClaimNumber>36< / pat:ClaimNumber> <pat:ClaimText>36. The electrically conductive paste of any one of claims 1-35, wherein the electrically conductive paste has an extensibility, measured according to Standard EN ISO 527-1 (Feb. 2012), of at least 30%. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00037"> <pat:ClaimNumber>37< / pat:ClaimNumber> <pat:ClaimText>37. The electrically conductive paste of claim 36, wherein the extensibility is 30% to 400%. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00038"> <pat:ClaimNumber>38< / pat:ClaimNumber> <pat:ClaimText>38. The electrically conductive paste of claim 36, wherein the extensibility is at least 40%. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00039"> <pat:ClaimNumber>39< / pat:ClaimNumber> <pat:ClaimText>39. The electrically conductive paste of claim 36, wherein the extensibility is 40% to 300%. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00040"> <pat:ClaimNumber>40< / pat:ClaimNumber> <pat:ClaimText>40. The electrically conductive paste of claim 36, wherein the extensibility is at least 60%. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00041"> <pat:ClaimNumber>41< / pat:ClaimNumber> <pat:ClaimText>41. The electrically conductive paste of claim 36, wherein the extensibility is 60% to 150%. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00042"> <pat:ClaimNumber>42< / pat:ClaimNumber> <pat:ClaimText>42. The electrically conductive paste of claim 36, wherein the extensibility is 80% to 150%. < / pat:ClaimText> < / pat:Claim> <pat:Claim com:id="CLM-00043"> <pat:ClaimNumber>43< / pat:ClaimNumber> <pat:ClaimText>43. A process for producing an electrically conductive paste, comprising the following process steps: a) a dispersion comprising an elastic binder is produced or provided; b) a conductive filler is introduced into the dispersion, the conductive filler comprising the following components: at least one conductive spherical filler, at least one conductive platelet- shaped filler, and at least one conductive rodlet-shaped filler, wherein the electrically conductive paste is for applying on an elastomer substrate. < / pat:ClaimText> < / pat:Claim> < / pat:Claims>