Fluid driving type actuator, manufacturing method of the same, and actuator system

Abstract

To provide a fluid driving type actuator which enables strain sensing and is excellent in durability against deformation.SOLUTION: A fluid driving type actuator of the invention includes: a tube member 10 which deforms when a fluid flows thereinto; and an elastic conductive layer 39 laminated on a part of or an entire part of at least one of an inner surface and an outer surface of the tube member 10. The fluid driving type actuator measures change of electric characteristics through the elastic conductive layer 30 to detect a deformation state of the tube member 10.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a fluid-driven actuator, a manufacturing method thereof, and an actuator system. [Background technology]

[0002] Various developments have been made regarding sensing technologies for actuators. For example, the technology described in Patent Document 1 is known as this type of technology. Patent Document 1 describes a fluid-driven actuator including a tubular elastic body composed of an electrically conductive first elastic sheet and a second elastic sheet, and two electrodes attached to the outer surface of the first elastic sheet (paragraph 0080, FIG. 6, etc. of Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-180829 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, as a result of investigations by the present inventors, it has become clear that the fluid-driven actuator described in Patent Document 1 leaves room for improvement in terms of durability against deformation. [Means for solving the problem]

[0005] After further investigation, the inventors discovered that in a fluid-driven actuator, by forming an elastic conductive layer on the surface of a tube member, it is possible to sense strain in the deformation state of the tube member via the elastic conductive layer, and to improve deformation durability when repeatedly deformed, thereby completing the present invention.

[0006] According to the present invention, A tube member that deforms when a fluid flows into it; and an elastic conductive layer laminated on a part or the entirety of at least one of an inner surface and an outer surface of the tube member, The deformation state of the tube member can be detected by measuring the change in electrical properties via the elastic conductive layer. A fluid-powered actuator is provided.

[0007] Further, according to the present invention, The above fluid-driven actuator; A measurement unit for measuring a change in the electrical characteristic; and a fluid pressure control unit that detects the deformation state of the tube member based on the change in the measured electrical characteristic, and adjusts the pressure of the fluid flowing into the tube member in accordance with the deformation state of the tube member. An actuator system is provided.

[0008] Further, according to the present invention, A method for manufacturing a fluid-driven actuator comprising: a tube member that deforms when a fluid flows into it; and an elastic conductive layer laminated on a surface of the tube member. forming the tube member using an insulating elastomer; and forming the stretchable conductive layer on part or the entirety of at least one of the inner surface and the outer surface of the tube member using a conductive paste. Effect of the Invention

[0009] According to the present invention, there are provided a fluid-driven actuator capable of sensing strain and having excellent durability against deformation, a method for manufacturing the same, and an actuator system. [Brief description of the drawings]

[0010] [Figure 1] 1 is a diagram showing an example of the configuration of a fluid-driven actuator of the present embodiment. [Diagram 2] 1. (a) is a cross-sectional view taken along line AA in FIG. 1, (b) is a cross-sectional view taken along line BB in FIG. 1, and (c) is a cross-sectional view taken along line CC in FIG. [Diagram 3] 11A and 11B are diagrams showing modified examples of the configuration of the fluid-driven actuator of the present embodiment. [Figure 4] FIG. 1 is a graph showing the relationship between the applied pressure and the rate of change in tube circumference in the expansion tests of Examples 1 and 2. [Diagram 5] 1 is a diagram showing the relationship between the applied pressure and the resistance value of the stretchable conductive layer in the expansion test of Examples 1 and 2. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In all drawings, similar components are given similar reference numerals and their explanations will be omitted as appropriate. Also, the drawings are schematic diagrams and do not correspond to the actual dimensional ratios.

[0012] The fluid-driven actuator of this embodiment will be outlined below.

[0013] The fluid-driven actuator of this embodiment comprises a tube member that deforms when a fluid flows into it, and an elastic conductive layer laminated over part or the entirety of at least one of the inner and outer surfaces of the tube member, and is capable of detecting the deformation state of the tube member by measuring changes in the electrical properties via the elastic conductive layer.

[0014] A fluid-driven actuator is a driving device that uses a fluid such as gas or liquid to expand or contract a tube member and converts it into mechanical motion. Specific fluids include gases such as air and nitrogen, and liquids such as water and oil.

[0015] Fluid-driven actuators can be used for a wide variety of purposes, including artificial muscles used in everyday life such as nursing care, welfare, medical care, lifestyle, and sports, and in medical settings; artificial muscles that assist in work such as agriculture, manufacturing, and construction; and as drive devices for artificial muscles and joint structures of robots.

[0016] According to this embodiment, a fluid-driven actuator capable of sensing strain and having excellent durability against deformation can be realized.

[0017] Each component of the fluid-driven actuator of this embodiment will now be described in detail.

[0018] 1 and 2 show an example of the configuration of a fluid-driven actuator (actuator 100). The actuator 100 in FIG. 1 comprises at least a tube member 10 and a stretchable conductive layer 30.

[0019] The tube member 10 is made of a cylindrical elastic body that expands and contracts due to the pressure of the fluid. The tube member 10 is capable of expanding and contracting in the axial direction, and / or of expanding or bending in at least one radial direction.

[0020] The actuator 100 may have a cap 20 on at least one of the ends of the tube member 10 . The cap 20 is composed of a lid member provided on the axial end of the tube member 10. The cap 20 may have a hole 22 as shown in FIG. 2(b). A fluid can be injected or discharged into the space 12 of the tube member 10 through the hole 22. When a fluid is injected into the space 12, the tube member 10 expands in the radial direction and contracts in the axial direction (FIGS. 2(b) and 2(c)). That is, the actuator 100 generates a contraction force in the axial direction of the tube member 10 and an expansion force in the radial direction.

[0021] The elastic conductive layer 30 functions as an elastic sensor section that detects deformation of the tube member 10, such as expansion, contraction, or bending.

[0022] The elastic conductive layer 30 is laminated on at least one of the inner surface and the outer surface of the tube member 10, partially or entirely.

[0023] In the actuator 100, the state in which the tube member 10 and the elastic conductive layer 30 are laminated may be a state in which their surfaces are in surface contact with each other and are chemically and / or physically bonded to each other and in close contact with each other. This can reduce the risk of damage, such as peeling of the elastic conductive layer 30 from the surface of the tube member 10, even during elongation or repeated elongation. This makes it possible to realize an actuator 100 with excellent deformation durability.

[0024] Such an elastic conductive layer 30 is configured to cover at least a portion of the surface of the expanded and / or contracted tubular member 10. Covering means covering at least a portion or the entire surface.

[0025] The elastic conductive layer 30 deforms in response to the deformation of the tube member 10, and its electrical characteristics change. By measuring the change in the electrical characteristics, it is possible to detect the deformation state of the tube member 10. In other words, the elastic conductive layer 30 functions as a strain sensor for the tube member 10 that utilizes the piezoresistive effect.

[0026] Here, an example of measuring the change in resistance value of the elastic conductive layer 30 will be described. For example, as shown in Fig. 1, the stretchable conductive layer 30 may have a ring structure extending circumferentially around the axis on the outer surface of the tube member 10. As shown in Fig. 2(a), this stretchable conductive layer 30 has some parts that are not continuous in the circumferential direction when viewed in cross section in the axial direction and are spaced apart. 1(a) to 1(b), when the tube member 10 contracts in the axial direction and expands in the radial direction, the elastic conductive layer 30 is stretched in the circumferential direction. At this time, the change in the resistance value of the elastic conductive layer 30 before and after the deformation of the tube member 10 can be measured. For example, a wire (not shown) is connected to the end of the elastic conductive layer 30, and the resistance value is measured via the wire.

[0027] In this way, when the tube member 10 expands radially and contracts axially when a fluid flows in, as shown in Figures 1(a) and (b), the elastic conductive layer 30 deforms in response, and the expansion state of the tube member 10 can be detected via the elastic conductive layer 30.

[0028] The elastic conductive layer 30 may be configured to be formed on the inner surface of the tube member 10. As a result, even if there is a risk of contact between the outer surface of the tube member 10 and a sleeve or other member, since the elastic conductive layer 30 is present inside the tube member 10, it is possible to stably measure changes in the electrical properties of the elastic conductive layer 30. Furthermore, by forming the elastic conductive layer 30 on the inside of the tube member 10, it is possible to suppress a decrease in the ease of expansion of the tube member 10 compared to when the elastic conductive layer 30 is on the outside.

[0029] The tube member 10 may be made of an insulating elastomer and / or the stretchable conductive layer 30 may be made of a conductive elastomer.

[0030] The insulating elastomer and the conductive elastomer are each made of an elastomer having elasticity. Since the elastic conductive layer 30 containing the conductive elastomer is laminated on the tube member 10 containing the insulating elastomer, it is possible to improve durability even when stretched.

[0031] The tube member 10 and the elastic conductive layer 30 may be configured to contain the same type of elastomer, such as the same type of silicone rubber. This allows the elastic conductive layer 30 to also undergo plastic deformation to the same extent, even if the elastomer of the tube member 10 undergoes plastic deformation due to repeated use. This makes it possible to detect the deformation state of the tube member 10, including the amount of plastic deformation.

[0032] By configuring the tube member 10 and the elastic conductive layer 30 to contain the same type of silicone rubber, the adhesion between them can be improved. Therefore, even when the tube member 10 is deformed, peeling or displacement of the elastic conductive layer 30 can be prevented. When the elastic conductive layer 30 is formed on the inner surface of the tube member 10, it is preferable that the elastic conductive layer 30 is configured in this way.

[0033] A modification of the actuator 100 will now be described.

[0034] The tube member 10 may have a cylindrical structure extending in the axial direction, or may have a curved structure that is curved entirely or partially.

[0035] The tube member 10 may have one or more spaces 12 therein. Specifically, the tube member 10 may have a plurality of spaces 12 divided by one or more rings, or by bonding the inner surfaces of the silicone rubber layers to each other. The plurality of spaces 12 are arranged so as to be aligned in the axial direction of the tube member 10.

[0036] The tube member 10 may be a single layer in a radial cross section, or may be composed of two or more layers. The layer may be composed of one or more types of silicone rubber layers. For example, a fiber layer may be provided between two silicone rubber layers. Furthermore, the tube member 10 may have two or more silicone rubber layers with different elasticity rates or a layer other than silicone rubber in at least a portion thereof.

[0037] The stretchable conductive layer 30 may be formed only on the inner surface as shown in FIG. 1, may be formed only on the outer surface, or may be formed on both the inner and outer surfaces so as to sandwich the tube member 10.

[0038] A stretchable cover layer may be formed on the stretchable conductive layer 30. This can improve the durability of the stretchable conductive layer 30. The stretchable cover layer can prevent the stretchable conductive layer 30 on the inner surface from coming into contact with degrading components contained in the fluid. On the other hand, the stretchable cover layer can prevent the stretchable conductive layer 30 on the outer surface from coming into contact with the sleeve or other members.

[0039] The stretchable cover layer may be made of an insulating elastomer, and may be made of the same material as the tube member 10 .

[0040] Another example of the stretchable conductive layer 30 may be a strain sensor of the tube member 10 using capacitance. In this case, the strain sensor is composed of a stretchable capacitor. In the stretchable capacitor, the tube member 10 made of an insulating elastomer is used as a capacitance film made of a stretchable conductive material, and the stretchable conductive layer 30 can be used as two stretchable electrodes sandwiching the capacitance film.

[0041] The change in capacitance of the tube member 10 can be measured via the elastic conductive layers 30 formed on both the inner and outer surfaces of the tube member 10 so as to sandwich the tube member 10. Since the thickness of the tube member 10 varies depending on the radial expansion state, based on the same principle as the capacitance varies depending on the thickness of the insulating film of a capacitor, the thickness variation can be measured as the amount of change in capacitance. The deformation state of the tube member 10 can then be grasped from the thickness.

[0042] In this embodiment, the change in electrical properties measured through the elastic conductive layer 30 can be at least one of a change in the resistance value of the elastic conductive layer 30 and a change in the capacitance of the tube member 10 sandwiched between the elastic conductive layers 30.

[0043] As shown in FIG. 1, the stretchable conductive layer 30 may have a ring structure extending in the circumferential direction, a line structure extending in the axial direction, or a tube structure extending in the circumferential and axial directions.

[0044] The ring structure may be annular or non-annular. When the stretchable conductive layer 30 has a ring structure, it may be provided at the end side in the axial direction of the tube member 10 as shown in Fig. 1(a) or at the center. The ring structure may be O-shaped or C-shaped in cross section in the axial direction.

[0045] When the elastic conductive layer 30 has a line shape, it may have various shapes and can be formed in various wiring patterns such as linear, wavy, etc. The elastic conductive layer 30 is formed by a coating means such as printing using a conductive paste, as will be described in detail later, so that a pattern of a desired shape and wiring thickness can be realized.

[0046] As shown in Fig. 3(a), the stretchable conductive layer 30 may have a tube structure having a space 12. Fig. 3(b) is a cross-sectional view taken along line DD of Fig. 3(a). The tubular stretchable conductive layer 30 is configured to cover at least a part or the entire inner surface of the tube member 10. This can improve the mechanical strength of the actuator 100 itself.

[0047] The cap 20 may be installed on the inner circumferential surface of the tube member 10, or may be installed on the outer circumferential surface of the tube member 10. The cap 20 may have a connecting mechanism for connecting to another mechanism or member.

[0048] The actuator 100 may also have a sleeve on the outer circumferential surface of the tube member 10. The sleeve is made of a cylindrical member, and covers at least a part of the outer surface of the outer circumferential surface of the tube member 10. Such a sleeve may have a mesh-like reinforcing structure made of fibers. The actuator 100 having the tube member 10 and the sleeve serves as a McKibben artificial muscle.

[0049] In one example of the actuator 100 of this embodiment, the tube member 10 is made of an insulating elastomer, and the stretchable conductive layer 30 is made of a conductive elastomer. These elastomers will be described.

[0050] Examples of the insulating elastomer that can be used include silicone rubber, urethane rubber, fluororubber, nitrile rubber, acrylic rubber, styrene rubber, chloroprene rubber, ethylene propylene rubber, etc. Among these, the elastomer includes one or more thermosetting elastomers (elastomer materials) selected from the group consisting of silicone rubber, urethane rubber, and fluororubber. The insulating elastomer may be composed of an elastomer material alone, or may be composed to include an elastomer material and a non-conductive filler. An example of the insulating elastomer includes silicone rubber, and preferably includes silicone rubber and a non-conductive filler. Silicone rubber is chemically stable among elastomers, and also has excellent mechanical strength. Among these, from the viewpoint of hygiene, it is preferable to use silicone rubber, which has high biocompatibility, as the elastomer material.

[0051] The conductive elastomer may be, for example, silicone rubber, urethane rubber, fluororubber, nitrile rubber, acrylic rubber, styrene rubber, chloroprene rubber, ethylene propylene rubber, etc. Among these, the elastomer includes one or more thermosetting elastomers (elastomer materials) selected from the group consisting of silicone rubber, urethane rubber, and fluororubber, and a conductive filler. A preferred example of the conductive elastomer includes silicone rubber and a conductive filler, which can enhance the elasticity and conductivity of the conductive elastomer.

[0052] At least one of the insulating elastomer and the conductive elastomer, and preferably both of them, may contain a non-conductive filler. As the non-conductive filler, a known material may be used, for example, silica particles, silicone rubber particles, talc, etc. Among these, silica particles may be used.

[0053] The conductive filler may include, for example, one or more selected from the group consisting of powdery or fibrous metal-based fillers, carbon-based fillers, metal oxide fillers, and metal-plated fillers. Among these, the conductive filler may be a carbon-based filler such as carbon or a metal-based filler such as silver powder.

[0054] In addition to the conductive filler, the conductive elastomer may further contain a non-conductive filler, which can improve the mechanical properties of the conductive elastomer.

[0055] At least two, or all, of the conductive elastomer of the stretchable conductive layer 30, the insulating elastomer of the tubular member 10, and the insulating elastomer of the stretchable cover layer may be constructed to comprise the same elastomeric material.

[0056] In this specification, containing the same elastomer material means containing at least one of the same type of elastomer material among the types of thermosetting elastomers exemplified above. When the same silicone rubber is contained, the silicone rubber may be constituted by a cured product of a silicone rubber-based curable composition containing a vinyl group-containing organopolysiloxane.

[0057] The insulating elastomer may be composed of a cured product of a silicone rubber-based curable composition containing a vinyl group-containing organopolysiloxane, and the conductive elastomer may be composed of a conductive filler and a cured product of a silicone rubber-based curable composition containing a vinyl group-containing organopolysiloxane.

[0058] The components of the silicone rubber-based hardenable composition will be described in detail below.

[0059] In this specification, containing the same silicone rubber means that the silicone rubber-based curable composition contains at least the same type of vinyl group-containing linear organopolysiloxane, and may further contain one or more selected from the group consisting of the same type of crosslinking agent, the same type of non-conductive filler, the same type of silane coupling agent, and the same type of catalyst.

[0060] The insulating elastomer may be composed of a cured product of a silicone rubber-based curable composition containing a vinyl group-containing organopolysiloxane, and the conductive elastomer may be composed of a conductive filler and a cured product of a silicone rubber-based curable composition containing a vinyl group-containing organopolysiloxane.

[0061] The same type of vinyl-containing linear organopolysiloxanes are those that contain at least the same vinyl groups as functional groups and have a linear structure, but may differ in the amount of vinyl groups in the molecule, the molecular weight distribution, or the amount added.

[0062] Crosslinking agents of the same type are sufficient if they have at least a common structure such as a linear structure or a branched structure, and may have different molecular weight distributions in the molecule or different functional groups, or may have different amounts added.

[0063] Non-conductive fillers of the same type may have at least a common constituent material, and may differ in particle size, specific surface area, surface treatment agent, or the amount of the surface treatment agent added.

[0064] Silane coupling agents of the same type are sufficient as long as they have at least a common functional group, and may differ in other functional groups in the molecule or in the amount added.

[0065] The same type of catalyst is sufficient if it has at least common constituent materials, and may contain different compositions in the catalyst, or may have different amounts of the components added.

[0066] The silicone rubber-based curable composition constituting the same silicone rubber may further contain one or more components selected from the group consisting of different types of vinyl group-containing linear organopolysiloxanes, crosslinking agents, non-conductive fillers, silane coupling agents, and catalysts.

[0067] The silicone rubber-based hardening composition of the present embodiment may contain a vinyl group-containing organopolysiloxane (A). The vinyl group-containing organopolysiloxane (A) is a polymer that is the main component of the silicone rubber-based hardening composition of the present embodiment.

[0068] The vinyl group-containing organopolysiloxane (A) can contain a vinyl group-containing linear organopolysiloxane (A1) having a linear structure.

[0069] The vinyl group-containing linear organopolysiloxane (A1) has a linear structure and contains vinyl groups, and these vinyl groups become crosslinking points during curing.

[0070] The vinyl group content of the vinyl group-containing linear organopolysiloxane (A1) is not particularly limited, but for example, it is preferable that the vinyl group content is 15 mol% or less and that the vinyl group content is 2 or more in the molecule. This optimizes the amount of vinyl groups in the vinyl group-containing linear organopolysiloxane (A1), and ensures the formation of a network with each component described below.

[0071] In this specification, the vinyl group content refers to the mol % of vinyl group-containing siloxane units when all units constituting the vinyl group-containing linear organopolysiloxane (A1) are taken as 100 mol %, where it is considered that there is one vinyl group per vinyl group-containing siloxane unit.

[0072] The degree of polymerization of the vinyl group-containing linear organopolysiloxane (A1) is not particularly limited, but is, for example, preferably within the range of about 1000 to 10000, and more preferably about 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) measured by GPC (gel permeation chromatography) using chloroform as a developing solvent.

[0073] In this specification, the symbol "to" indicates that the upper and lower limits are included, unless otherwise specified.

[0074] Furthermore, the specific gravity of the vinyl group-containing linear organopolysiloxane (A1) is not particularly limited, but is preferably in the range of about 0.9 to 1.1.

[0075] By using a vinyl group-containing linear organopolysiloxane (A1) having a degree of polymerization and specific gravity within the above ranges, it is possible to improve the heat resistance, flame retardancy, chemical stability, etc. of the resulting silicone rubber.

[0076] As the vinyl group-containing linear organopolysiloxane (A1), those having a structure represented by the following formula (1) are particularly preferred.

[0077] [ka]

[0078] In formula (1), R 1 is a substituted or unsubstituted alkyl group, alkenyl group, aryl group, or a hydrocarbon group consisting of a combination thereof, each having 1 to 10 carbon atoms. Examples of the alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group, and a propyl group, with a methyl group being preferred. Examples of the alkenyl group having 1 to 10 carbon atoms include a vinyl group, an allyl group, and a butenyl group, with a vinyl group being preferred. Examples of the aryl group having 1 to 10 carbon atoms include a phenyl group.

[0079] Also, R 2 is a substituted or unsubstituted alkyl group, alkenyl group, aryl group, or a hydrocarbon group consisting of a combination thereof, each having 1 to 10 carbon atoms. Examples of the alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group, and a propyl group, and among these, 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.

[0080] Also, R 3 is a substituted or unsubstituted alkyl group having 1 to 8 carbon atoms, an aryl group, or a hydrocarbon group consisting of a combination thereof. Examples of the alkyl group having 1 to 8 carbon atoms include a methyl group, an ethyl group, and a propyl group, and among these, a methyl group is preferable. Examples of the aryl group having 1 to 8 carbon atoms include a phenyl group.

[0081] Furthermore, R in formula (1) 1 and R 2 Examples of the substituent of R include a methyl group and a vinyl group. 3 Examples of the substituent include a methyl group.

[0082] In addition, in formula (1), multiple R 1 are independent of each other and may be different or the same. 2 , and R 3 The same applies to.

[0083] Furthermore, m and n are the numbers of repeating units constituting the vinyl group-containing linear organopolysiloxane (A1) represented by formula (1), where m is an integer of 0 to 2000 and n is an integer of 1000 to 10000. m is preferably 0 to 1000 and n is preferably 2000 to 5000.

[0084] A specific example of the structure of the vinyl group-containing linear organopolysiloxane (A1) represented by formula (1) is that represented by the following formula (1-1).

[0085] [ka]

[0086] 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.

[0087] The vinyl group-containing linear organopolysiloxane (A1) may contain a first vinyl group-containing linear organopolysiloxane (A1-1) having two or more vinyl groups in the molecule and having a vinyl group content of 0.4 mol% or less. The vinyl group content of the first vinyl group-containing linear organopolysiloxane (A1-1) may be 0.1 mol% or less.

[0088] The vinyl group-containing linear organopolysiloxane (A1) may contain a first vinyl group-containing linear organopolysiloxane (A1-1) and a second vinyl group-containing linear organopolysiloxane (A1-2) having a vinyl group content of 0.5 to 15 mol %.

[0089] By combining the first vinyl group-containing linear organopolysiloxane (A1-1) and the second vinyl group-containing linear organopolysiloxane (A1-2) having a high vinyl group content as the raw rubber, which is the raw material of the silicone rubber, the vinyl groups can be unevenly distributed, and the crosslinking density can be more effectively formed in the crosslinked network of the silicone rubber. As a result, the tear strength of the silicone rubber can be more effectively increased.

[0090] Specifically, as the vinyl group-containing linear organopolysiloxane (A1), it is preferable to use, for example, a first vinyl group-containing linear organopolysiloxane (A1-1) having two or more units in which R1 is a vinyl group and / or units in which R2 is a vinyl group in the molecule and containing 0.4 mol % or less of these units in the above formula (1-1), and a second vinyl group-containing linear organopolysiloxane (A1-2) containing 0.5 to 15 mol % of units in which R1 is a vinyl group and / or units in which R2 is a vinyl group.

[0091] The first vinyl group-containing linear organopolysiloxane (A1-1) preferably has a vinyl group content of 0.01 to 0.2 mol %, and the second vinyl group-containing linear organopolysiloxane (A1-2) preferably has a vinyl group content of 0.8 to 12 mol %.

[0092] Furthermore, when the first vinyl group-containing linear organopolysiloxane (A1-1) and the second vinyl group-containing linear organopolysiloxane (A1-2) are combined and blended, the ratio of (A1-1) to (A1-2) is not particularly limited, but for example, the weight ratio of (A1-1):(A1-2) is preferably 50:50 to 95:5, and more preferably 80:20 to 90:10.

[0093] The first and second vinyl group-containing linear organopolysiloxanes (A1-1) and (A1-2) may each be used alone or in combination of two or more.

[0094] The vinyl group-containing organopolysiloxane (A) may also contain a vinyl group-containing branched organopolysiloxane (A2) having a branched structure.

[0095] <<Organohydrogenpolysiloxane (B)>> The silicone rubber-based hardenable composition of this embodiment can contain an organohydrogenpolysiloxane (B). The organohydrogenpolysiloxane (B) is classified into a linear organohydrogenpolysiloxane (B1) having a linear structure and a branched organohydrogenpolysiloxane (B2) having a branched structure, and may contain either one or both of these.

[0096] The linear organohydrogenpolysiloxane (B1) has a linear structure and a structure in which hydrogen is directly bonded to Si (≡Si-H), and is a polymer that undergoes a hydrosilylation reaction with the vinyl groups of the vinyl group-containing organopolysiloxane (A) and with vinyl groups of components blended into the silicone rubber-based curable composition, thereby crosslinking these components.

[0097] The molecular weight of the linear organohydrogenpolysiloxane (B1) is not particularly limited, but for example, the weight average molecular weight is preferably 20,000 or less, and more preferably 1,000 or more and 10,000 or less.

[0098] The weight average molecular weight of the linear organohydrogenpolysiloxane (B1) can be measured, for example, by polystyrene conversion in gel permeation chromatography (GPC) using chloroform as a developing solvent.

[0099] Furthermore, it is usually preferred that the linear organohydrogenpolysiloxane (B1) does not have a vinyl group, which can reliably prevent the crosslinking reaction from proceeding within the molecule of the linear organohydrogenpolysiloxane (B1).

[0100] As the linear organohydrogenpolysiloxane (B1) as described above, for example, one having a structure represented by the following formula (2) is preferably used.

[0101] [ka]

[0102] In formula (2), R4 is a substituted or unsubstituted alkyl group, alkenyl group, aryl group, a hydrocarbon group combining these groups, or a hydride group having 1 to 10 carbon atoms. Examples of the alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group, a propyl group, etc., and among these, 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, etc. Examples of the aryl group having 1 to 10 carbon atoms include a phenyl group.

[0103] Also, R 5 is a substituted or unsubstituted alkyl group, alkenyl group, aryl group, a hydrocarbon group combining these groups, or a hydride group having 1 to 10 carbon atoms. Examples of the alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group, and a propyl group, and among these, 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.

[0104] In addition, in formula (2), multiple R 4 are independent of each other and may be different or the same. 5 The same applies to R. 4 and R 5 At least two of these are hydride groups.

[0105] Also, R 6 is a substituted or unsubstituted alkyl group having 1 to 8 carbon atoms, an aryl group, or a hydrocarbon group combining these. Examples of the alkyl group having 1 to 8 carbon atoms include a methyl group, an ethyl group, and a propyl group, and among these, a methyl group is preferable. Examples of the aryl group having 1 to 8 carbon atoms include a phenyl group. 6 are independent of each other and may be different from each other or may be the same.

[0106] In addition, R in formula (2) 4 ,R 5 ,R6 Examples of the substituent include a methyl group and a vinyl group, and from the viewpoint of preventing an intramolecular crosslinking reaction, a methyl group is preferred.

[0107] Furthermore, m and n are the numbers of repeating units constituting the linear organohydrogenpolysiloxane (B1) represented by formula (2), where 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.

[0108] The linear organohydrogenpolysiloxane (B1) may be used alone or in combination of two or more kinds.

[0109] Since the branched organohydrogenpolysiloxane (B2) has a branched structure, it forms regions with high crosslink density, and is a component that greatly contributes to the formation of a sparsely-dense structure of crosslink density in the silicone rubber system. Also, like the linear organohydrogenpolysiloxane (B1), it has a structure in which hydrogen is directly bonded to Si (≡Si-H), and undergoes a hydrosilylation reaction with the vinyl groups of the vinyl group-containing organopolysiloxane (A) and with the vinyl groups of the components blended in the silicone rubber-based hardening composition, forming a polymer that crosslinks these components.

[0110] The specific gravity of the branched organohydrogenpolysiloxane (B2) is in the range of 0.9 to 0.95.

[0111] Furthermore, it is usually preferred that the branched organohydrogenpolysiloxane (B2) does not have a vinyl group, which can reliably prevent the crosslinking reaction from proceeding within the molecule of the branched organohydrogenpolysiloxane (B2).

[0112] As the branched organohydrogenpolysiloxane (B2), one represented by the following average composition formula (c) is preferred.

[0113] Average composition formula (c) (Ha (R 7 ) 3-a SiO 1 / 2 ) m (SiO 4 / 2 ) n (In formula (c), R 7 is a monovalent organic group, a is an integer ranging from 1 to 3, and m is H a (R 7 ) 3-a SiO 1 / 2 The number of units, n, is SiO 4 / 2 (the number of units)

[0114] 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 consisting of a combination thereof. Examples of the alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group, and a propyl group, and among these, a methyl group is preferred. Examples of the aryl group having 1 to 10 carbon atoms include a phenyl group.

[0115] In formula (c), a is the number of hydride groups (hydrogen atoms directly bonded to Si) and is an integer ranging from 1 to 3, and preferably 1.

[0116] In addition, in formula (c), m is H a (R 7 ) 3-a SiO 1 / 2 The number of units, n, is SiO 4 / 2 It is the number of units.

[0117] The branched organohydrogenpolysiloxane (B2) has a branched structure. The linear organohydrogenpolysiloxane (B1) and the branched organohydrogenpolysiloxane (B2) differ in that their structures are linear or branched, and the number of alkyl groups R bonded to Si (R / Si) when the number of Si is 1 is in the range of 1.8 to 2.1 for the linear organohydrogenpolysiloxane (B1) and 0.8 to 1.7 for the branched organohydrogenpolysiloxane (B2).

[0118] Since the branched organohydrogenpolysiloxane (B2) has a branched structure, for example, when heated in a nitrogen atmosphere to 1000° C. at a heating rate of 10° C. / min, the amount of residue is 5% or more. In contrast, since the linear organohydrogenpolysiloxane (B1) is linear, the amount of residue after heating under the above conditions is almost zero.

[0119] Specific examples of the branched organohydrogenpolysiloxane (B2) include those having a structure represented by the following formula (3).

[0120] [ka]

[0121] In formula (3), R 7 R 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, and a propyl group, and among these, a methyl group is preferable. Examples of the aryl group having 1 to 8 carbon atoms include a phenyl group. 7 Examples of the substituent include a methyl group.

[0122] In addition, in formula (3), multiple R 7 are independent of each other and may be different from each other or may be the same.

[0123] In addition, in formula (3), "-O-Si≡" indicates that Si has a branched structure extending three-dimensionally.

[0124] The branched organohydrogenpolysiloxane (B2) may be used alone or in combination of two or more kinds.

[0125] In addition, the amount of hydrogen atoms (hydride groups) directly bonded to Si in the linear organohydrogenpolysiloxane (B1) and the branched organohydrogenpolysiloxane (B2) is not particularly limited. However, in the silicone rubber-based curable composition, the total amount of hydride groups in the linear organohydrogenpolysiloxane (B1) and the branched organohydrogenpolysiloxane (B2) is preferably 0.5 to 5 moles, more preferably 1 to 3.5 moles, per mole of vinyl group in the vinyl group-containing linear organopolysiloxane (A1). This ensures that a crosslinked network is formed between the linear organohydrogenpolysiloxane (B1) and the branched organohydrogenpolysiloxane (B2) and the vinyl group-containing linear organopolysiloxane (A1).

[0126] <<Silica particles (C)>> The silicone rubber-based hardenable composition of this embodiment may contain silica particles (C) as a non-conductive filler, if necessary.

[0127] The silica particles (C) are not particularly limited, but for example, fumed silica, calcined silica, precipitated silica, etc. These may be used alone or in combination of two or more kinds.

[0128] The silica particles (C) have a specific surface area, as measured by the BET method, of, for example, 50 to 400 m 2 / g, and 100 to 400m 2 / g is more preferable. The average primary particle size of the silica particles (C) is, for example, preferably from 1 to 100 nm, and more preferably from about 5 to 20 nm.

[0129] By using silica particles (C) having a specific surface area and average particle size within this range, it is possible to improve the hardness and mechanical strength, particularly the tensile strength, of the silicone rubber that is formed.

[0130] <<Silane coupling agent (D)>> The silicone rubber-based hardenable composition of this embodiment may contain a silane coupling agent (D). The silane coupling agent (D) may have a hydrolyzable group. The hydrolyzable group is hydrolyzed by water to become a hydroxyl group, and the hydroxyl group undergoes a dehydration condensation reaction with the hydroxyl group on the surface of the silica particles (C), thereby modifying the surface of the silica particles (C).

[0131] In addition, the silane coupling agent (D) may contain a silane coupling agent having a hydrophobic group. This provides the surface of the silica particles (C) with this hydrophobic group, so that the cohesive force of the silica particles (C) in the silicone rubber-based curable composition and in the silicone rubber is reduced (there is less cohesion due to hydrogen bonds caused by silanol groups), and as a result, it is presumed that the dispersibility of the silica particles in the silicone rubber-based curable composition is improved. This increases the interface between the silica particles and the rubber matrix, and enhances the reinforcing effect of the silica particles. Furthermore, it is presumed that the slipperiness of the silica particles in the matrix is ​​improved during deformation of the rubber matrix. And, due to the improvement in the dispersibility and slipperiness of the silica particles (C), the mechanical strength (for example, tensile strength, tear strength, etc.) of the silicone rubber due to the silica particles (C) is improved.

[0132] Furthermore, the silane coupling agent (D) may contain a silane coupling agent having a vinyl group. This allows the vinyl group to be introduced onto the surface of the silica particles (C). Therefore, when the silicone rubber-based curable composition is cured, that is, when the vinyl group of the vinyl group-containing organopolysiloxane (A) and the hydride group of the organohydrogenpolysiloxane (B) undergo a hydrosilylation reaction to form a network (crosslinked structure), the vinyl group of the silica particles (C) also participates in the hydrosilylation reaction with the hydride group of the organohydrogenpolysiloxane (B), so that the silica particles (C) are also incorporated into the network. This allows the formed silicone rubber to have a low hardness and a high modulus.

[0133] As the silane coupling agent (D), a silane coupling agent having a hydrophobic group and a silane coupling agent having a vinyl group can be used in combination.

[0134] An example of the silane coupling agent (D) is one represented by the following formula (4).

[0135] Y n -Si-(X) 4-n (4) In the above formula (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 a hydrophobic group. X represents a hydrolyzable group.

[0136] The hydrophobic group is an alkyl group having 1 to 6 carbon atoms, an aryl group, or a hydrocarbon group formed by combining these groups, and examples thereof include a methyl group, an ethyl group, a propyl group, and a phenyl group, with a methyl group being particularly preferred.

[0137] In addition, the hydrophilic group may be, for example, a hydroxyl group, a sulfonic acid group, a carboxyl group, or a carbonyl group, and among these, a hydroxyl group is particularly preferred. Note that, although a hydrophilic group may be included as a functional group, it is preferable that the hydrophilic group is not included from the viewpoint of imparting hydrophobicity to the silane coupling agent (D).

[0138] Further, examples of the hydrolyzable group include alkoxy groups such as methoxy and ethoxy groups, chloro groups, and silazane groups. Among these, silazane groups are preferred because of their high reactivity with the silica particles (C). In addition, those having a silazane group as a hydrolyzable group can be easily obtained by adding (Y n -Si-) structures.

[0139] Specific examples of the silane coupling agent (D) represented by the above formula (4) include, for example, alkoxysilanes such as methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, and decyltrimethoxysilane; chlorosilanes such as methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, and phenyltrichlorosilane; and hexamethyldisilazane, which have a hydrophobic group as a functional group. Examples of the silane having a vinyl group include alkoxysilanes such as methacryloxypropyltriethoxysilane, methacryloxypropyltrimethoxysilane, methacryloxypropylmethyldiethoxysilane, methacryloxypropylmethyldimethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, and vinylmethyldimethoxysilane; chlorosilanes such as vinyltrichlorosilane and vinylmethyldichlorosilane; and divinyltetramethyldisilazane. Among these, taking into consideration the above description, it is particularly preferable that the silane having a hydrophobic group is hexamethyldisilazane, and the silane having a vinyl group is divinyltetramethyldisilazane.

[0140] In this embodiment, the lower limit of the content of the silane coupling agent (D) is preferably 1% by mass or more, more preferably 3% by mass or more, and even more preferably 5% by mass or more, based on 100 parts by weight of the total amount of the vinyl group-containing organopolysiloxane (A). The upper limit of the content of the silane coupling agent (D) is preferably 100% by mass or less, more preferably 80% by mass or less, and even more preferably 40% by mass or less, based on 100 parts by weight of the total amount of the vinyl group-containing organopolysiloxane (A). By making the content of the silane coupling agent (D) equal to or more than the above lower limit, when silica particles (C) are used, it is possible to improve the mechanical strength of the silicone rubber as a whole. Also, by making the content of the silane coupling agent (D) equal to or less than the above upper limit, it is possible for the silicone rubber to have appropriate mechanical properties.

[0141] <<Platinum or platinum compounds (E)>> The silicone rubber-based hardenable composition of this embodiment may contain platinum or a platinum compound (E). Platinum or a platinum compound (E) is a catalytic component that acts as a catalyst during curing. The amount of platinum or a platinum compound (E) added is a catalytic amount.

[0142] As the platinum or platinum compound (E), known substances can be used, such as platinum black, platinum supported on silica or carbon black, chloroplatinic acid or an alcohol solution of chloroplatinic acid, a complex salt of chloroplatinic acid and an olefin, and a complex salt of chloroplatinic acid and a vinylsiloxane.

[0143] The platinum or platinum compound (E) may be used alone or in combination of two or more kinds.

[0144] <<Water(F)>> Furthermore, the silicone rubber-based hardening composition of this embodiment may contain water (F) in addition to the above components (A) to (E).

[0145] Water (F) functions as a dispersion medium for dispersing each component contained in the silicone rubber-based hardening composition, and is also a component that contributes to the reaction between the silica particles (C) and the silane coupling agent (D). Therefore, the silica particles (C) and the silane coupling agent (D) can be more reliably linked to each other in the silicone rubber, and uniform properties can be exhibited overall.

[0146] Furthermore, when water (F) is contained, its content can be appropriately set, but specifically, for example, it is preferably in the range of 10 to 100 parts by weight, more preferably in the range of 30 to 70 parts by weight, relative to 100 parts by weight of the silane coupling agent (D). This makes it possible to more reliably proceed with the reaction between the silane coupling agent (D) and the silica particles (C).

[0147] (Other Ingredients) Furthermore, the silicone rubber-based hardening composition of the present embodiment may further contain other components in addition to the above components (A) to (F), such as inorganic fillers other than the silica particles (C), such as diatomaceous earth, iron oxide, zinc oxide, titanium oxide, barium oxide, magnesium oxide, cerium oxide, calcium carbonate, magnesium carbonate, zinc carbonate, glass wool, and mica, as well as additives such as reaction inhibitors, dispersants, pigments, dyes, antistatic agents, antioxidants, flame retardants, and thermal conductivity improvers.

[0148] In the silicone rubber-based hardening composition, the content ratio of each component is not particularly limited, but is set, for example, as follows.

[0149] In this embodiment, the upper limit of the content of the silica particles (C) may be, for example, 60 parts by weight or less, preferably 50 parts by weight or less, and more preferably 40 parts by weight or less, based on 100 parts by weight of the total amount of the vinyl group-containing organopolysiloxane (A). This allows the balance of mechanical strength such as hardness and tensile strength to be achieved. The lower limit of the content of the silica particles (C) is not particularly limited, based on 100 parts by weight of the total amount of the vinyl group-containing organopolysiloxane (A), but may be, for example, 10 parts by weight or more.

[0150] The silane coupling agent (D) is preferably contained in an amount of 5 parts by weight or more and 100 parts by weight or less, more preferably 5 parts by weight or more and 40 parts by weight or less, per 100 parts by weight of the vinyl group-containing organopolysiloxane (A), which can reliably improve the dispersibility of the silica particles (C) in the silicone rubber-based curable composition.

[0151] The content of the organohydrogenpolysiloxane (B) is preferably, for example, 0.5 parts by weight or more and 20 parts by weight or less, and more preferably 0.8 parts by weight or more and 15 parts by weight or less, based on 100 parts by weight of the total amount of the vinyl group-containing organopolysiloxane (A), the silica particles (C), and the silane coupling agent (D). By keeping the content of (B) within the above range, a more effective curing reaction may be achieved.

[0152] The content of platinum or platinum compound (E) means the amount of catalyst, and can be set appropriately, but specifically, the amount of platinum group metal in this component is 0.01 to 1000 ppm by weight, preferably 0.1 to 500 ppm, relative to the total amount of vinyl group-containing organopolysiloxane (A), silica particles (C), and silane coupling agent (D). By making the content of platinum or platinum compound (E) equal to or greater than the lower limit, the obtained silicone rubber composition can be sufficiently cured. By making the content of platinum or platinum compound (E) equal to or less than the upper limit, the curing speed of the obtained silicone rubber composition can be improved.

[0153] Furthermore, when water (F) is contained, its content can be appropriately set, but specifically, for example, it is preferably in the range of 10 to 100 parts by weight, more preferably in the range of 30 to 70 parts by weight, relative to 100 parts by weight of the silane coupling agent (D). This makes it possible to more reliably proceed with the reaction between the silane coupling agent (D) and the silica particles (C).

[0154] <Silicone rubber manufacturing method> Next, a method for producing the silicone rubber of this embodiment will be described. In the method for producing the silicone rubber of this embodiment, a silicone rubber-based hardening composition is prepared, and the silicone rubber can be obtained by hardening the silicone rubber-based hardening composition. Details are provided below.

[0155] First, the components of the silicone rubber-based hardening composition are mixed uniformly using any kneading device to prepare the silicone rubber-based hardening composition.

[0156] [1] For example, a predetermined amount of vinyl group-containing organopolysiloxane (A), silica particles (C), and a silane coupling agent (D) are weighed out, and then kneaded using any kneading device to obtain a kneaded product containing these components (A), (C), and (D).

[0157] It is preferable to prepare this mixture by first kneading the vinyl-containing organopolysiloxane (A) with the silane coupling agent (D) and then kneading (mixing) the silica particles (C), which improves the dispersibility of the silica particles (C) in the vinyl-containing organopolysiloxane (A).

[0158] In addition, when obtaining this kneaded product, water (F) may be added to the kneaded product of the components (A), (C), and (D) as necessary, which allows the reaction between the silane coupling agent (D) and the silica particles (C) to proceed more reliably.

[0159] Furthermore, it is preferable that the kneading of each of the components (A), (C), and (D) is carried out through a first step of heating at a first temperature and a second step of heating at a second temperature. This allows the surface of the silica particles (C) to be surface-treated with the coupling agent (D) in the first step, and allows the by-products generated by the reaction between the silica particles (C) and the coupling agent (D) to be reliably removed from the kneaded product in the second step. After that, the component (A) may be added to the obtained kneaded product as necessary, and further kneaded. This allows the compatibility of the components in the kneaded product to be improved.

[0160] The first temperature is preferably, for example, about 40 to 120° C., and more preferably, for example, about 60 to 90° C. The second temperature is preferably, for example, about 130 to 210° C., and more preferably, for example, about 160 to 180° C.

[0161] Moreover, 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.

[0162] Furthermore, the time for the first step is, for example, preferably about 0.3 to 1.5 hours, and more preferably about 0.5 to 1.2 hours, and the time for the second step is, for example, preferably about 0.7 to 3.0 hours, and more preferably about 1.0 to 2.0 hours.

[0163] By setting the above conditions for the first and second steps, the above effects can be obtained more significantly.

[0164] [2] Next, the organohydrogenpolysiloxane (B) and platinum or a platinum compound (E) are weighed out in predetermined amounts, and then the components (B) and (E) are kneaded into the mixture prepared in the above step [1] using any kneading device to obtain a silicone rubber-based curable composition. The obtained silicone rubber-based curable composition may be a paste containing a solvent.

[0165] In addition, when mixing the components (B) and (E), it is preferable to mix the mixture prepared in the above step [1] with the organohydrogenpolysiloxane (B) and the mixture prepared in the above step [1] with platinum or a platinum compound (E), and then mix the mixtures together. This allows the components (A) to (E) to be reliably dispersed in the silicone rubber-based curable composition without allowing the reaction between the vinyl group-containing organopolysiloxane (A) and the organohydrogenpolysiloxane (B) to proceed.

[0166] The temperature at which the components (B) and (E) are kneaded is, for example, preferably about 10 to 70°C, and more preferably about 25 to 30°C, as roll setting temperature.

[0167] Furthermore, the kneading time is, for example, preferably about 5 minutes to 1 hour, and more preferably about 10 to 40 minutes.

[0168] In the above steps [1] and [2], by setting the temperature within the above range, the progress of the reaction between the vinyl group-containing organopolysiloxane (A) and the organohydrogenpolysiloxane (B) can be more reliably prevented or inhibited. In addition, in the above steps [1] and [2], by setting the kneading time within the above range, the components (A) to (E) can be more reliably dispersed in the silicone rubber-based curable composition.

[0169] The kneading device used in each of steps [1] and [2] is not particularly limited, but for example, a kneader, a two-roll mill, a Banbury mixer (continuous kneader), a pressure kneader, etc. can be used.

[0170] In addition, a reaction inhibitor such as 1-ethynylcyclohexanol may be added to the kneaded mixture in step [2], which makes it possible to more effectively prevent or inhibit the progress of the reaction between the vinyl group-containing organopolysiloxane (A) and the organohydrogenpolysiloxane (B) even if the temperature of the kneaded mixture is set to a relatively high temperature.

[0171] [3] Next, the silicone rubber-based hardenable composition is hardened to form a silicone rubber.

[0172] In this embodiment, the curing process of the silicone rubber-based curable resin composition is carried out, for example, by heating at 100 to 250° C. for 1 to 30 minutes (first curing) and then post-baking at 200° C. for 1 to 4 hours (second curing).

[0173] Through the above steps, a silicone rubber made of a cured product of the silicone rubber-based curable resin composition is obtained.

[0174] [3] Next, the silicone rubber-based hardening composition obtained in step [2] is dissolved in a solvent to obtain an insulating paste. [3] Next, the silicone rubber-based hardening composition obtained in step [2] is dissolved in a solvent, and a conductive filler is added to obtain a conductive paste.

[0175] (solvent) The conductive paste and the insulating paste contain a solvent. As the solvent, various known solvents can be used, including, for example, high boiling point solvents. These may be used alone or in combination of two or more kinds.

[0176] The lower limit of the boiling point of the high boiling point solvent is, for example, 100°C or higher, preferably 130°C or higher, and more preferably 150°C or higher. This can improve the printing stability of screen printing and the like. On the other hand, the upper limit of the boiling point of the high boiling point solvent is not particularly limited, but may be, for example, 300°C or lower, 290°C or lower, or 280°C or lower. This can suppress excessive heat history during wiring formation, thereby preventing damage to the base and maintaining a good shape of the wiring formed from the conductive paste.

[0177] The solvent can be appropriately selected from the viewpoints of the solubility and boiling point of the silicone rubber-based curable resin composition, and can include, for example, an aliphatic hydrocarbon having 5 to 20 carbon atoms, preferably an aliphatic hydrocarbon having 8 to 18 carbon atoms, and more preferably an aliphatic hydrocarbon having 10 to 15 carbon atoms.

[0178] Examples of the solvent include aliphatic hydrocarbons such as pentane, hexane, cyclohexane, heptane, methylcyclohexane, ethylcyclohexane, octane, decane, dodecane, and tetradecane; aromatic hydrocarbons such as benzene, toluene, ethylbenzene, xylene, mesitylene, trifluoromethylbenzene, and benzotrifluoride; diethyl ether, diisopropyl ether, dibutyl ether, cyclopentyl methyl ether, cyclopentyl ethyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, and diethylene glycol dimethyl ether. Examples of the ethers include ethanol monobutyl ether, dipropylene glycol dimethyl ether, dipropylene glycol methyl-n-propyl ether, 1,4-dioxane, 1,3-dioxane, and tetrahydrofuran; haloalkanes such as dichloromethane, chloroform, 1,1-dichloroethane, 1,2-dichloroethane, 1,1,1-trichloroethane, and 1,1,2-trichloroethane; carboxylic acid amides such as N,N-dimethylformamide and N,N-dimethylacetamide; sulfoxides such as dimethyl sulfoxide and diethyl sulfoxide; and esters such as diethyl carbonate. These may be used alone or in combination of two or more. The solvent used here may be appropriately selected from among solvents capable of uniformly dissolving or dispersing the components in the conductive paste.

[0179] The above solvents are the polar term of the Hansen solubility parameters (δ p ) is, for example, 10MPa 1 / 2 or less, preferably 7 MPa 1 / 2 More preferably, it is 5.5 MPa or less. 1 / 2 The silicone rubber-based hardening resin composition may contain a first solvent having the polarity (δ) of 1 to 3. This makes it possible to improve the dispersibility and solubility of the silicone rubber-based hardening resin composition in the paste. p The lower limit of the pressure is not particularly limited, but may be, for example, 0 Pa. 1 / 2 More than that is fine.

[0180] The hydrogen bond term of the Hansen solubility parameters in the first solvent (δ h ) is, for example, 20MPa 1 / 2 or less, preferably 10 MPa 1 / 2 More preferably, it is 7 MPa or less. 1 / 2 This makes it possible to improve the dispersibility and solubility of the silicone rubber-based hardening resin composition in the paste. h The lower limit of the pressure is not particularly limited, but may be, for example, 0 Pa. 1 / 2 More than that is fine.

[0181] Hansen solubility parameters (HSP) are an index that indicates the degree to which a substance dissolves in another substance. HSP expresses solubility as a three-dimensional vector. This three-dimensional vector is typically expressed by the dispersion term (δ d ), polarity term (δ p ), hydrogen bond term (δ h ) and it can be determined that compounds with similar vectors have high solubility. The similarity of vectors can be determined by the Hansen Solubility Parameter distance (HSP distance).

[0182] As used herein, the Hansen Solubility Parameters (HSP values) can be calculated using software called HSPiP (Hansen Solubility Parameters in Practice), where the computer software HSPiP developed by Hansen and Abbott includes a function for calculating HSP distances and a database of Hansen parameters for various resins and solvents or non-solvents. The solubility of each resin in pure solvents and mixed solvents of good and poor solvents is investigated, and the results are entered into the HSPiP software to calculate D: dispersion term, P: polarity term, H: hydrogen bond term, and R0: radius of the solubility sphere.

[0183] As the solvent of this embodiment, for example, one having a small difference in HSP distance, polarity term, or hydrogen bond term between the elastomer or the structural units constituting the elastomer and the solvent can be selected.

[0184] The lower limit of the viscosity of the conductive paste and / or insulating paste when measured at a shear rate of 20 [1 / s] at room temperature of 25°C is, for example, 1 Pa·s or more, preferably 5 Pa·s or more, and more preferably 10 Pa·s or more. This can improve film formability. Also, shape retention can be improved even when a thick film is formed. On the other hand, the upper limit of the viscosity of the conductive paste and / or insulating paste at room temperature of 25°C is, for example, 100 Pa·s or less, preferably 90 Pa·s or less, and more preferably 80 Pa·s or less. This can improve the printability of the paste.

[0185] At room temperature of 25°C, the viscosity measured at a shear rate of 1 [1 / s] is η1, the viscosity measured at a shear rate of 5 [1 / s] is η5, and the thixotropic index is the viscosity ratio (η1 / η5). In this case, the lower limit of the thixotropy index of the conductive paste and / or insulating paste is, for example, 1.0 or more, preferably 1.1 or more, and more preferably 1.2 or more. This allows the shape of the wiring obtained by the printing method to be stably maintained. On the other hand, the upper limit of the thixotropy index of the conductive paste and / or insulating paste is, for example, 3.0 or less, preferably 2.5 or less, and more preferably 2.0 or less. This allows the paste to be easily printed.

[0186] The content of the silicone rubber-based curable composition in the insulating paste is preferably 10% by mass or more, more preferably 15% by mass or more, and even more preferably 20% by mass or more, based on 100% by mass of the insulating paste. The content of the silicone rubber-based curable composition in the insulating paste is preferably 50% by mass or less, more preferably 40% by mass or less, and even more preferably 35% by mass or less, based on 100% by mass of the insulating paste.

[0187] (Conductive filler) As the conductive filler, a known conductive material may be used, but metal powder (G) may also be used. The metal constituting the metal powder (G) is not particularly limited, but may include, for example, at least one of copper, silver, gold, nickel, tin, lead, zinc, bismuth, antimony, or metal powder alloyed with these, or two or more of these. Of these, the metal powder (G) preferably contains silver or copper, that is, silver powder or copper powder, because of their high electrical conductivity and ready availability. These metal powders (G) may also be coated with other metals.

[0188] In this embodiment, the shape of the metal powder (G) is not limited, but conventional shapes such as dendritic, spherical, scale-like, etc. may be used. Among these, scale-like metal powder (G) may be used.

[0189] The particle size of the metal powder (G) is not limited. For example, the average particle size D 50 The particle size of the metal powder (G) is, for example, an average particle size D 50 It is preferably 1,000 μm or less, more preferably 100 μm or less, and further preferably 20 μm or less. Average particle size D 50By setting the value in this range, the silicone rubber can exhibit an appropriate electrical conductivity. The particle size of the metal powder (G) can be defined as the average particle size of 200 arbitrarily selected metal powder particles obtained by observing, for example, the conductive paste or silicone rubber molded using the conductive paste with a transmission electron microscope and performing image analysis.

[0190] The content of the conductive filler in the conductive paste is preferably 30% by mass or more, more preferably 40% by mass or more, and even more preferably 50% by mass or more, based on 100% by mass of the conductive paste. The content of the conductive filler in the conductive paste is preferably 85% by mass or less, more preferably 75% by mass or less, and even more preferably 65% ​​by mass or less, based on 100% by mass of the conductive paste. By making the content of the conductive filler equal to or greater than the above lower limit, the silicone rubber can have appropriate conductive properties. By making the content of the conductive filler equal to or less than the above upper limit, the silicone rubber can have appropriate flexibility.

[0191] The content of the silicone rubber-based hardening composition in the conductive paste is preferably 1% by mass or more, more preferably 3% by mass or more, and even more preferably 5% by mass or more, based on 100% by mass of the conductive paste. The content of the silicone rubber-based hardening composition in the conductive paste is preferably 25% by mass or less, more preferably 20% by mass or less, and even more preferably 15% by mass or less, based on 100% by mass of the conductive paste. By making the content of the silicone rubber-based hardening composition equal to or greater than the above lower limit, the silicone rubber can have an appropriate degree of flexibility, while by making the content of the silicone rubber-based hardening composition equal to or less than the above upper limit, the mechanical strength of the silicone rubber can be improved.

[0192] The lower limit of the content of the silica particles (C) in the conductive paste is, for example, 1% by mass or more, preferably 3% by mass or more, and more preferably 5% by mass or more, based on 100% by mass of the total amount of the silica particles (C) and the conductive filler. This can improve the mechanical strength of the silicone rubber. On the other hand, the upper limit of the content of the silica particles (C) in the conductive paste is, for example, 20% by mass or less, preferably 15% by mass or less, and more preferably 10% by mass or less, based on 100% by mass of the total amount of the silica particles (C) and the conductive filler. This can balance the elastic electrical properties and mechanical strength of the silicone rubber.

[0193] The content of the conductive filler in the conductive cured product obtained by curing the conductive paste that constitutes the wiring such as the lower wiring and the upper wiring is preferably 65% ​​by mass or more, more preferably 70% by mass or more, and even more preferably 75% by mass or more, based on 100% by mass of the conductive cured product. The content of the conductive filler in the conductive cured product is preferably 95% by mass or less, more preferably 90% by mass or less, and even more preferably 85% by mass or less, based on 100% by mass of the conductive cured product. By setting the content of the conductive filler to be equal to or greater than the above lower limit, the silicone rubber can have appropriate conductive properties, while by setting the content of the conductive filler to be equal to or less than the above upper limit, the silicone rubber can have appropriate flexibility.

[0194] In this embodiment, the above silicone rubber-based curable composition is cured to obtain an insulating elastomer. Furthermore, the silicone rubber-based hardening composition can be used to obtain insulating elastomers having a tube structure by various molding methods such as extrusion molding and compression molding. Alternatively, the insulating paste may be used to form a coating film by various coating means such as printing, spraying, dipping, etc., and then dried to obtain an insulating elastomer. As with the insulating paste, the conductive paste can be used to form a coating film by various coating means such as printing, spraying, dipping, etc., and then dried to obtain a conductive elastomer.

[0195] The method for producing the fluid-driven actuator of this embodiment includes the steps of forming a tube member using an insulating elastomer, and forming a stretchable conductive layer using a conductive paste on a part or the entirety of at least one of the inner surface and the outer surface of the tube member, thereby obtaining a fluid-driven actuator including a tube member that deforms when a fluid flows into it, and a stretchable conductive layer laminated on the surface of the tube member.

[0196] As a specific example of a manufacturing process for the actuator 100, for example, a silicone rubber-based curable composition is used and extruded into a tube shape using an extruder to obtain a tube member 10 containing an insulating elastomer. A conductive paste is applied to the inner surface and / or outer surface of the obtained tube member 10, and then dried to form the actuator 100 in which a stretchable conductive layer 30 containing a conductive elastomer is laminated on the inner surface and / or outer surface of the tube member 10.

[0197] The upper limit of the durometer hardness A of the insulating elastomer is not particularly limited, but may be, for example, 80 or less, preferably 70 or less, and more preferably 65 or less. This allows the cured physical properties of the silicone rubber to be well balanced. This increases the deformability of the silicone rubber, which allows it to be easily deformed, such as by bending or stretching. On the other hand, the lower limit of the durometer hardness A is, for example, 40 or more, preferably 42 or more, and more preferably 48 or more. This can suppress deformation due to external stress. Also, the friction durability and mechanical strength of the silicone rubber can be improved.

[0198] (Durometer hardness A measurement procedure) A sheet-like test piece is prepared using the cured product of the silicone rubber-based curable composition, and the durometer hardness A of the obtained sheet-like test piece at 25° C. is measured in accordance with JIS K6253 (1997).

[0199] The lower limit of the tensile strength of the insulating elastomer is, for example, 5.0 MPa or more, preferably 6.0 MPa or more, and more preferably 7.0 MPa or more, which makes it possible to realize a structure having excellent elongation durability when repeatedly subjected to elongation deformation. On the other hand, the upper limit of the tensile strength is not particularly limited, but may be, for example, 25 MPa or less, which allows the various properties of the silicone rubber to be well balanced.

[0200] (Procedure for measuring tensile strength) A dumbbell-shaped No. 3 test piece is prepared using the cured product of the silicone rubber-based curable composition in accordance with JIS K6251 (2004), and the tensile strength of the dumbbell-shaped No. 3 test piece at 25°C is measured.

[0201] The lower limit of the breaking elongation of the insulating elastomer is, for example, 500% or more, preferably 600% or more, and more preferably 700% or more, which can improve the elongation durability during repeated elongation deformation. On the other hand, the upper limit of the breaking elongation is not particularly limited, but may be, for example, 2000% or less, or 1800% or less, which allows the various properties of the silicone rubber to be well balanced.

[0202] (Measurement conditions for breaking elongation) A dumbbell-shaped No. 3 test piece is prepared using the cured product of the silicone rubber-based curable composition in accordance with JIS K6251 (2004), and the resulting dumbbell-shaped No. 3 test piece is measured for breaking elongation at 25° C. The breaking elongation is calculated by [gauge line movement distance (mm)] ÷ [initial gauge line distance (20 mm)] × 100.

[0203] The lower limit of the tear strength of the insulating elastomer is, for example, 25 N / mm or more, preferably 28 N / mm or more, more preferably 30 N / mm or more, even more preferably 33 N / mm or more, and even more preferably 34 N / mm or more. This can improve the durability of the silicone rubber during repeated use. Also, the scratch resistance and mechanical strength of the silicone rubber can be improved. On the other hand, the upper limit of the tear strength is not particularly limited, but may be, for example, 80 N / mm or less, or 70 N / mm or less, which allows the various properties of the silicone rubber to be well balanced.

[0204] (Measuring procedure for tear strength) A crescent-shaped test piece is prepared from the cured product of the silicone rubber-based curable composition in accordance with JIS K6252 (2001), and the tear strength of the obtained crescent-shaped test piece at 25°C is measured.

[0205] In this embodiment, for example, by appropriately selecting the type and amount of each component contained in the silicone rubber-based hardening composition, the preparation method of the silicone rubber-based hardening composition, etc., it is possible to control the hardness, tensile strength, breaking elongation, and tear strength. Among these, for example, appropriately controlling the type and blending ratio of the resin constituting the silicone rubber, the crosslinking density and crosslinking structure of the resin, etc., improving the blending ratio of the inorganic filler and the bond of the inorganic filler with the rubber, using a first vinyl group-containing linear organopolysiloxane (A1-1) with a vinyl group content of 0.4 mol% or less, using a silane coupling agent having a vinyl group, and appropriately adjusting the content of the silica particles (C) and the content of the silane coupling agent, etc., are listed as elements for making the hardness, tensile strength, breaking elongation, and tear strength into the desired numerical range.

[0206] The actuator system of this embodiment will be described. An example of the configuration of the actuator system includes the above-mentioned fluid-driven actuator, a measurement unit that measures changes in electrical characteristics, and a fluid pressure control unit that adjusts the pressure of the fluid flowing into the tube member.

[0207] The measurement unit measures changes in electrical properties, such as changes in resistance of the elastic conductive layer and changes in capacitance of the capacitor constituted by the elastic conductive layer, via the elastic conductive layer provided in the fluid-driven actuator.

[0208] The fluid pressure control unit detects the deformation state of the tube member based on the change in the electrical characteristics measured by the measuring unit, and adjusts the pressure of the fluid flowing into the tube member according to the deformation state of the tube member. For example, the fluid pressure control unit can adjust the pressure to increase or decrease so that the degree of expansion of the tube member is within a desired range based on the relationship between the resistance value of the elastic conductive layer and the deformation state of the tube member. This makes it possible to more accurately control the degree of deformation of the tube member even after the tube member is repeatedly deformed by expansion, contraction, and the like. The information regarding the relationship between the change in electrical characteristics and the deformation state of the tube member as described above can be acquired and stored in advance.

[0209] Each component included in the measurement unit and the fluid pressure control unit may be configured with dedicated hardware, or may be realized by executing a software program suitable for each component. Each component may be realized by a program execution unit such as a CPU or a processor reading and executing a software program recorded on a recording medium such as a hard disk or a semiconductor memory.

[0210] Although the embodiments of the present invention have been described above, these are merely examples of the present invention, and various configurations other than those described above can be adopted. Furthermore, the present invention is not limited to the above-described embodiments, and modifications and improvements within the scope of the present invention are included in the present invention. EXAMPLES

[0211] The present invention will be described in detail below with reference to examples, but the present invention is not limited to the descriptions of these examples. The raw material components shown in Table 1 are as follows: (A1-1): First vinyl group-containing linear organopolysiloxane: A vinyl group-containing dimethylpolysiloxane (structure represented by the above formula (1-1)) synthesized according to the following synthesis scheme 1. (A1-2): Second vinyl group-containing linear organopolysiloxane: A vinyl group-containing dimethylpolysiloxane (having the structure represented by the above formula (1-1) and R 1 and R 2 is a vinyl group)

[0212] (Organohydrogenpolysiloxane (B)) (B-1): Organohydrogenpolysiloxane: Momentive Corporation, "TC-25D"

[0213] (Silica particles (C)) (C): Silica microparticles (particle size 7 nm, specific surface area 300 m 2 / g), manufactured by Nippon Aerosil Co., Ltd., "AEROSIL300"

[0214] (Silane coupling agent (D)) (D-1): Hexamethyldisilazane (HMDZ), manufactured by Gelest, "HEXAMETHYLDISILAZANE (SIH6110.1)" (D-2) Divinyltetramethyldisilazane, manufactured by Gelest, "1,3-DIVINYLTETRAMETHYLDISILAZANE (SID4612.0)"

[0215] (Platinum or platinum compounds (E)) (E-1): Platinum compound (manufactured by Momentive, product name "TC-25A")

[0216] (Water(F)) (F):Pure water

[0217] (Metal powder (G)) (G1): Silver powder, manufactured by Tokuriki Chemical Laboratory, product name "TC-101", median diameter d 50 : 8.0μm, aspect ratio 16.4, average major axis 4.6μm

[0218] (Synthesis of vinyl group-containing organopolysiloxane (A)) [Synthesis Scheme 1: Synthesis of First Vinyl Group-Containing Linear Organopolysiloxane (A1-1)] A first vinyl group-containing linear organopolysiloxane (A1-1) was synthesized according to the following formula (5). That is, 74.7 g (252 mmol) of octamethylcyclotetrasiloxane and 0.1 g of potassium siliconate were placed in a 300 mL separable flask equipped with a cooling tube and stirring blade and replaced with Ar gas, and the temperature was raised and the mixture was stirred at 120° C. for 30 minutes. At this time, an increase in viscosity was confirmed. The mixture was then heated to 155° C. and stirred for 3 hours, after which 0.1 g (0.6 mmol) of 1,3-divinyltetramethyldisiloxane was added and the mixture was stirred at 155° C. for an additional 4 hours. After four hours, the mixture was diluted with 250 mL of toluene and then washed three times with water. The washed organic layer was washed several times with 1.5 L of methanol for reprecipitation purification, and the oligomer and polymer were separated. The resulting polymer was dried overnight at 60°C under reduced pressure to obtain a first vinyl group-containing linear organopolysiloxane (A1-1) (Mn = 2.2 × 10 5 , Mw=4,8×10 5 The vinyl group content calculated from H-NMR spectrum measurement was 0.04 mol %.

[0219] [ka]

[0220] [Synthesis Scheme 2: Synthesis of the second vinyl-containing linear organopolysiloxane (A1-2)] In the synthesis step of (A1-1) above, except that 0.86 g (2.5 mmol) of 2,4,6,8-tetramethyl-2,4,6,8-tetravinylcyclotetrasiloxane was used in addition to 74.7 g (252 mmol) of octamethylcyclotetrasiloxane, the same synthesis step as (A1-1) was carried out to synthesize a second vinyl group-containing linear organopolysiloxane (A1-2) as shown in the following formula (6). (Mn = 2.3 x 105, Mw = 5.0 x 105). The vinyl group content calculated by H-NMR spectrum measurement was 0.93 mol%.

[0221] [ka]

[0222] (Preparation of Silicone Rubber-Based Curable Composition) Silicone rubber-based curable compositions Samples 1 and 2 were prepared according to the following procedure. First, a mixture of 90% vinyl group-containing organopolysiloxane (A), silane coupling agent (D), and water (F) was pre-kneaded in the proportions shown in Table 1 below, and then silica particles (C) were added to the mixture and further kneaded to obtain a kneaded product (silicone rubber compound). Here, the kneading after the addition of the silica particles (C) was carried out through a first step of kneading for 1 hour under conditions of 60 to 90°C in a nitrogen atmosphere for the coupling reaction, and a second step of kneading for 2 hours under conditions of 160 to 180°C in a reduced pressure atmosphere for the removal of the by-product (ammonia). Thereafter, the mixture was cooled, and the remaining 10% of the vinyl group-containing organopolysiloxane (A) was added in two portions and kneaded for 20 minutes. Next, organohydrogenpolysiloxane (B), platinum or a platinum compound (E) was added to 100 parts by weight of the obtained kneaded product (silicone rubber compound) in the proportions shown in Table 2 below, and kneaded with a roll to obtain a silicone rubber-based curable composition.

[0223] (Preparation of conductive paste) 13.7 parts by weight of the obtained silicone rubber-based curable composition of Sample 2 was immersed in 31.8 parts by weight of tetradecane (solvent), then stirred with a planetary centrifugal mixer, 54.5 parts by weight of metal powder (G1) was added, and the mixture was kneaded with a triple roll mill to obtain a conductive paste.

[0224] [Table 1]

[0225] [Table 2]

[0226] (Fabrication of a fluid-driven actuator) The silicone rubber-based hardening composition of Sample 1 or Sample 2 was extruded into a tube using an extruder to obtain a silicone rubber tube member having the dimensions shown in Table 2. The obtained conductive paste was applied to the circumference of the outer surface of the obtained silicone rubber tube member, drawing a pattern with a width of 1 mm and a length of 20 mm, and this was heated and cured at 200°C for 4 hours to form a conductive silicone rubber sensor part with a thickness of 50 μm. This resulted in the production of a tube with a conductive sensor unit (fluid-driven actuator) as shown in Figure 2, which has a tube member 10 made of an insulating elastomer and an elastic conductive layer 30 (elastic sensor unit) made of a conductive elastomer laminated on the outer surface of the tube member 10.

[0227] <Tube expansion test and strain sensing evaluation> Caps were attached to both ends of the obtained tube with conductive sensor part, and in a tube expansion test, pressure was applied to the inside of the tube through one of the caps to introduce air. As the pressure for injecting the air was gradually increased, the outer circumference (mm) on the outer surface of the tube and the resistance value (Ω) of the elastic sensor part from the wiring connected to both ends were measured over time. The circumference was measured using a circumference gauge, and the resistance was measured using an electrical resistance meter. The circumference change rate was calculated based on [(circumferential length of tube when pressure is applied - initial circumference length of tube when pressure is not applied) / (initial circumference length of tube when pressure is not applied)] x 100. The results for the tubes of Examples 1 and 2 are shown in Table 3. The relationships between pressure and circumference change rate, and between pressure and resistance in Table 3 were plotted, respectively, to create the graphs shown in Figures 4 and 5. Figures 4 and 5 show that the resistance value of the elastic sensor part also varies depending on the change in the tube's circumference, i.e., the degree of deformation of the tube, and it was found that the tube with conductive sensor part in each embodiment is capable of strain sensing.

[0228] [Table 3] <Durability to deformation> The above tube expansion test was carried out under the condition of repeating expansion from 0 MPa to 0.06 MPa to 0 MPa 10 times using the tubes with conductive sensor parts of Examples 1 and 2. After that, it was confirmed that there was no peeling between the tube and the conductive sensor part, and that the resistance value of the conductive sensor part could be measured.

[0229] <Expansion control> The tube expansion test was carried out by applying a pressure of 0.12 MPa (first time) to the conductive sensor tube of Example 2, removing the air, and then applying a pressure of 0.12 MPa again (second time). The change in circumference of the tube was about 10% in the first time and about 12% in the second time. By adjusting the pressure so that the second resistance value of the conductive sensor part was approximately the same as the first resistance value immediately after the second pressure application, it was possible to control the peripheral change rate to be approximately the same as the first peripheral change rate even from the second pressure application onwards.

[0230] <Easy expansion> A certain pressure was applied to the obtained tube with the conductive sensor part and a tube without the conductive sensor part, and air was injected to evaluate the degree of expansion. It was confirmed that in both cases, the rate of change in circumference at the same applied pressure was about the same.

[0231] (Preparation of silicone rubber for evaluation) The silicone rubber-based hardening composition obtained in Sample 1 or Sample 2 was pressed at 170°C and 10 MPa for 10 minutes to form a sheet with a thickness of 1 mm and was subjected to a primary hardening. It was then heated at 200°C for 4 hours to be subjected to a secondary hardening. As a result, a sheet-shaped silicone rubber (a hardened product of the silicone rubber-based hardening composition) was obtained.

[0232] The obtained silicone rubber sheet (elastomer sheet) was evaluated based on the following evaluation items. The results are shown in Table 4. The tensile strength and breaking elongation were measured on three samples, and the average of the three values ​​was used as the measured value. The tear strength was measured on five samples, and the average value of the five was recorded as the measured value. The hardness was measured five times and the average value was used as the measured value. The average values ​​are shown in the table. In the table, ">" indicates that the specimen did not break due to the stroke limit of the tensile tester.

[0233] <Hardness: Durometer hardness> Six of the obtained 1 mm thick sheet-like silicone rubbers were laminated to prepare a 6 mm test piece. The type A durometer hardness of the obtained test piece was measured at 25°C in accordance with JIS K6253 (1997).

[0234] <Tear strength> A crescent-shaped test piece was prepared in accordance with JIS K6252 (2001) using the obtained 1 mm thick sheet-like silicone rubber, and the tear strength (TS) of the obtained crescent-shaped test piece at 25°C was measured, with the unit being N / mm.

[0235] <Elongation at break> Using the obtained 1 mm thick sheet-like silicone rubber, dumbbell-shaped No. 3 test pieces were prepared in accordance with JIS K6251 (2004), and the breaking elongation of the obtained dumbbell-shaped No. 3 test pieces was measured at 25°C. The breaking elongation was calculated by [gauge line movement distance (mm)] ÷ [initial gauge line distance (20 mm)] × 100. The unit is %.

[0236] <Tensile strength> Using the obtained 1 mm thick sheet-like silicone rubber, dumbbell-shaped No. 3 test pieces were prepared in accordance with JIS K6251 (2004), and the tensile strength of the obtained dumbbell-shaped No. 3 test pieces at 25°C was measured (units are MPa).

[0237] [Table 4]

[0238] The conductive sensor tubes (fluid-driven actuators) of Examples 1 and 2 were capable of strain sensing and showed excellent durability against deformation. [Explanation of symbols]

[0239] 10 Tube member 12 Space 20 Cap 22 holes 30 Stretchable conductive layer 100 Actuator

Claims

1. A tube member that deforms when a fluid flows into it; and an elastic conductive layer laminated on a part or the entirety of at least one of an inner surface and an outer surface of the tube member, The deformation state of the tube member can be detected by measuring the change in electrical properties via the elastic conductive layer. Fluid-driven actuator.

2. 2. The fluid-driven actuator according to claim 1, The tube member is made of an insulating elastomer, The fluid-driven actuator, wherein the elastic conductive layer is made of a conductive elastomer.

3. 3. The fluid-driven actuator according to claim 2, A fluid-driven actuator, wherein the insulating elastomer has a tear strength of 25 N / mm or more as measured at 25° C. in accordance with JIS K6252 (2001).

4. 4. The fluid-driven actuator according to claim 2, A fluid-driven actuator, wherein the insulating elastomer has a breaking elongation of 500% or more, as measured at 25°C in accordance with JIS K6251 (2004).

5. The fluid-driven actuator according to any one of claims 2 to 4, A fluid-driven actuator, wherein the insulating elastomer has a tensile strength of 5.0 MPa or more, as measured at 25°C in accordance with JIS K6251 (2004).

6. The fluid-driven actuator according to any one of claims 2 to 5, At least one of the insulating elastomer and the conductive elastomer contains a non-conductive filler.

7. 7. The fluid-driven actuator according to claim 6, The fluid-driven actuator, wherein the non-conductive filler comprises silica particles.

8. The fluid-driven actuator according to any one of claims 2 to 7, The fluid-driven actuator, wherein the conductive elastomer contains a conductive filler.

9. 9. The fluid-driven actuator according to claim 8, The fluid-driven actuator, wherein the conductive filler comprises one or more fillers selected from the group consisting of a metal-based filler, a carbon-based filler, a metal oxide filler, and a metal-plated filler.

10. The fluid-driven actuator according to any one of claims 2 to 9, The fluid-driven actuator, wherein the insulating elastomer and the conductive elastomer are formed from a cured product of a silicone rubber-based curable composition containing the same type of vinyl group-containing organopolysiloxane.

11. The fluid-driven actuator according to any one of claims 1 to 10, A fluid-driven actuator, comprising: a stretchable cover layer formed on a surface of the stretchable conductive layer.

12. The fluid-driven actuator according to any one of claims 1 to 11, The fluid-powered actuator, wherein the stretchable conductive layer is formed on the inner surface of the tubular member.

13. The fluid-driven actuator according to any one of claims 1 to 12, The fluid-driven actuator includes a sleeve on an outer peripheral surface of the tube member.

14. The fluid-driven actuator according to any one of claims 1 to 13, When the fluid flows into the tube member, the tube member expands in the radial direction and contracts in the axial direction, A fluid-driven actuator capable of detecting the expansion state of the tube member.

15. The fluid-driven actuator according to any one of claims 1 to 14, A fluid-driven actuator, wherein the change in the electrical characteristic includes at least one of a change in resistance value of the stretchable conductive layer and a change in capacitance of the tube member sandwiched between the stretchable conductive layers.

16. A fluid-driven actuator according to any one of claims 1 to 15, A measurement unit for measuring a change in the electrical characteristic; and a fluid pressure control unit that detects the deformation state of the tube member based on the change in the measured electrical characteristic, and adjusts the pressure of the fluid flowing into the tube member in accordance with the deformation state of the tube member. Actuator system.

17. A method for manufacturing a fluid-driven actuator comprising: a tube member that deforms when a fluid flows into it; and an elastic conductive layer laminated on a surface of the tube member. forming the tube member using an insulating elastomer; and forming the stretchable conductive layer on part or the entirety of at least one of the inner surface and the outer surface of the tube member using a conductive paste.

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