Curable elastomer composition and cured product thereof, film having the cured product, laminate having the film and method for producing the same, electronic component or display device having the cured product, method for designing a curable elastomer composition, and method for designing a transducer device

Abstract

[Problem] Properties necessary for an electroactive polymer material that is used in a transducer device include dielectric breakdown strength, Young's modulus, dielectric constant, thickness and electromechanical instability; and these properties have a correlation with each other. The correlation among these properties, however, has not been defined yet and thus a huge amount of effort is required to find excellent materials for an optimum electroactive polymer material by trial and error, while an optimum electroactive polymer material that satisfies all requirements has not been achieved. [Solution] The above are achieved by means of a curable elastomer composition which contains a compound having a highly dielectric functional group, and a cured product of which satisfies formula AA (wherein E represents a dielectric breakdown strength within the range of from 50 V / μm to 200 V / μm; α represents a constant within the range of from 0.4 to 0.9; Y represents a Young's modulus within the range of from 0.001 MPa to 10 MPa; εγ represents a relative dielectric constant of 100 or less; and ε0 represents the dielectric constant of vacuum).

Description

[Technical Field]

[0001] The present invention relates to a curable elastomer composition and a cured product thereof, a film including the cured product, a laminate including the film and a method for producing the same, an electronic component or a display device including the cured product, a method for designing a curable elastomer, and a method for designing a transducer device. [Background technology]

[0002] A transducer device is an element or equipment that converts kinetic energy into electrical energy or electrical energy into kinetic energy, such as an actuator, sensor, or generator that replaces conventional technologies such as a motor. Electroactive polymer materials that can be used for the dielectric layer or electrode layer in a transducer device must have mechanical properties such as tensile strength, tear strength, and elongation, as well as electrical properties such as dielectric constant and dielectric breakdown strength.

[0003] Non-Patent Document 1 discloses that there are two causes of stress and strain induced in an isotropic dielectric by an electrostatic field. One is Maxwell stress, which is caused by changes in the electric field distribution within the dielectric due to strain. The other is electrostriction, which is related to changes in the dielectric properties of the material due to strain. It also discloses that the stress and strain resulting from both effects are quadratic functions of the magnitude of the electric field. Non-Patent Document 1 also discloses that accurate evaluation of electrostriction is particularly necessary for evaluating the electromechanical properties of electroactive polymer materials with a low Young's modulus, such as cross-linked polymers. While it shows correlations between Young's modulus, thickness change, and electric field strength, it makes no mention of dielectric breakdown strength, and fails to define the correlations between dielectric breakdown strength, dielectric constant, Young's modulus, etc.

[0004] Non-Patent Document 2 discloses that deformation of electroactive polymer materials, which has not been taken into consideration until now, affects the electrical properties of electroactive polymer materials, and therefore requires microscopic evaluation of the amount of deformation. Although the document shows a correlation between the amount of deformation and Young's modulus and electric field strength, it makes no mention of dielectric breakdown strength, and fails to define the correlation between dielectric breakdown strength, relative permittivity, Young's modulus, etc.

[0005] Non-Patent Document 3 discloses that, with regard to the electrical breakdown of electroactive polymer materials, increasing only the breakdown strength impairs other properties such as electrical durability. Furthermore, a model was developed for the electrothermal breakdown of polydimethylsiloxane elastomers, and it was revealed that the dielectric constant and electrical conductivity significantly affect the electrothermal breakdown of polydimethylsiloxane elastomers. Additionally, it was disclosed that the deformation, thickness, and electromechanical instability of electroactive polymer materials significantly affect the electrical breakdown strength. However, the correlation between these factors was not defined. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. 2014 / 105959 [Non-patent literature]

[0007] [Non-Patent Document 1] Krakovsky, I.; Romijn, T.; Posthuma De Boer, AJ Appl. Phys., 85, 628, 1999. [Non-patent document 2] Thakur, OP; Singh, AK Mater. Sci. - Poland, 27, 2009. [Non-patent document 3] Bin, ZS; Ladegaard, SA Technical University of Denmark Ph. D. thesis, 2016. Summary of the Invention [Problem to be solved by the invention]

[0008] The performance required for an electroactive polymer material used in a transducer device includes dielectric breakdown strength, Young's modulus, dielectric constant, thickness, and electromechanical instability, and it has been known from the prior art that these properties are correlated and affect the electromechanical properties, electrical durability, etc. However, the correlations among these properties have not yet been defined, and therefore, in order to select an optimal electroactive polymer material to be used in a transducer device, it is necessary to search for a superior material through trial and error, which requires a great deal of effort, and it has not been possible to provide an electroactive polymer material that satisfies all of the requirements.

[0009] The present invention has been made to solve the problems of the prior art described above, and aims to provide an optimal curable elastomer composition and a cured product thereof that have mechanical and electrical properties suitable for forming a transducer device.

[0010] Another object of the present invention is to provide an efficient method for designing a curable elastomer composition and a method for designing a transducer device without relying on trial and error. [Means for solving the problem]

[0011] The present inventors have intensively investigated the above-mentioned problems and arrived at the present invention. That is, an object of the present invention is to provide a curable composition containing a compound having a highly dielectric functional group, the cured product of which has the following formula:

number

[0012] The curable elastomer composition preferably cures by one or more curing reaction mechanisms selected from hydrosilylation reaction curing, condensation reaction curing, radical reaction curing, and high-energy ray curing reaction.

[0013] The curable elastomer composition comprises: (A) an organopolysiloxane having a curing reactive group containing at least two carbon-carbon double bonds in the molecule; (B) an organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms in the molecule, and (C) Hydrosilylation reaction catalyst It is preferred that the compound contains:

[0014] The component (A) of the curable elastomer composition is (a1) a linear or branched organopolysiloxane having alkenyl groups only at the molecular chain terminals, and optionally (a2) An alkenyl group-containing organopolysiloxane resin having at least one branched siloxane unit in the molecule and a vinyl (CH2=CH-) group content in the range of 1.0 to 5.0 mass%. Preferably, the organopolysiloxane is an organopolysiloxane containing the following or a mixture thereof.

[0015] The compound having a highly dielectric functional group in the curable elastomer composition is preferably an organopolysiloxane or an organohydrogenpolysiloxane.

[0016] The organopolysiloxane or organohydrogenpolysiloxane having a highly dielectric functional group of the curable elastomer composition preferably constitutes a part or all of component (A) or component (B).

[0017] A part or all of the component (A) or the component (B) of the curable elastomer composition contains (C p F 2p+1 Preferably, the organopolysiloxane or organohydrogenpolysiloxane has a fluoroalkyl group represented by the formula: )-R- (R is an alkylene group having 1 to 10 carbon atoms, and p is an integer of 1 or more and 8 or less).

[0018] The curable elastomer composition is preferably for use in a transducer device.

[0019] The present invention also relates to the cured product of the curable elastomeric composition of the present invention.

[0020] The present invention also relates to an electronic component or display device having the cured product of the present invention.

[0021] The present invention also relates to a film comprising the cured product of the present invention.

[0022] The present invention also relates to a laminate comprising the film of the present invention and a release layer.

[0023] The present invention also relates to a method for producing a laminate, comprising the steps of applying the curable elastomer composition of the present invention onto a separator having a release layer in the form of a thin film having a thickness of 1 to 1000 μm after curing, and curing the curable elastomer composition applied in the form of a thin film.

[0024] The manufacturing method preferably further includes a rolling process.

[0025] The present invention also relates to a cured product having the following formula:

number

[0026] The present invention also relates to a method for designing a transducer device, which comprises a step of using a cured product of a curable elastomer composition selected according to the method for designing a curable elastomer composition. [Effects of the Invention]

[0027] The curable elastomer composition of the present invention enables the cured product to satisfy the mechanical and electrical properties required for an electroactive polymer material used in a transducer device.

[0028] Furthermore, according to the method for designing a curable elastomer composition of the present invention, it is possible to determine, based on specific physical property values, whether the curable elastomer composition has the necessary mechanical and electrical properties as an electroactive polymer material used in a transducer device, and to design an optimal curable elastomer composition without trial and error. DETAILED DESCRIPTION OF THE INVENTION

[0029] [Curable elastomer composition] The curable elastomer composition of the present invention is characterized in that it contains a compound having a highly dielectric functional group, and the cured product thereof satisfies the following formula:

[0030]

number

[0031] The above formula is derived as follows: The dielectric breakdown strength E is treated as a parameter when the Maxwell stress and elastic deformation force described below are balanced. Here, during actual measurement, the dielectric breakdown strength E is a value measured using rigid electrodes, and the formulas for calculating Maxwell stress and the like below are for stress measured using rigid electrodes.

[0032]

number

[0033]

number

[0034] Considering that the deformation is quadratic when electroactive polymer materials are applied to transducers, it is reasonable to express the strain ε using the true strain ln(d / d0) rather than the nominal strain, where d is the film thickness during electrical stimulation and d0 is the initial film thickness. When the Maxwell stress and elastic deformation forces are balanced, the following equation is obtained for a rigid electrode:

[0035]

number

[0036] Based on equation (4), equation (5) (same as equation (1)) was obtained.

[0037]

number

[0038] For rigid electrodes, the film thickness d at the time of dielectric breakdown is d b where α is a constant expressed by formula (6). One of the features of the present invention is that this constant is in the range of 0.4 to 0.9, preferably 0.6 to 0.85.

[0039]

number

[0040] On the other hand, the dielectric breakdown strength E can also be measured using compliant electrodes, and can be treated as a parameter when the Maxwell stress and elastic deformation force described below are balanced. For reference, the calculation method is shown below.

number

[0041]

number

[0042] As with the rigid electrode, via the above equation (5), for the compliant electrode, the film thickness at the time of breakdown, d, is calculated as d b Then, α can be derived as a constant expressed as equation (9). As can be easily understood from the comparison of the equations, the constant α given under the rigid electrode condition is the value obtained by multiplying the constant α given under the compliant electrode condition by the square root of 2.

[0043]

number

[0044] [Dielectric breakdown strength] As used herein, "dielectric breakdown strength" refers to a measure of the dielectric breakdown resistance of a film of the cured product of the curable elastomer composition of the present invention under an applied DC or AC voltage. The dielectric breakdown strength value or dielectric breakdown voltage value is obtained by dividing the applied voltage before dielectric breakdown by the film thickness. That is, the dielectric breakdown strength in the present invention is measured in units of potential difference relative to the film thickness (in the present invention, volts / micrometer (V / μm)). Such dielectric breakdown strength can be measured using rigid electrodes with an electrical insulating oil breakdown voltage tester (e.g., Portatest 100A-2 manufactured by Soken Co., Ltd.) having a program conforming to standards such as JIS 2101-82.

[0045] In the above formula, the dielectric breakdown strength E is a value measured using rigid electrodes, and is 50 V / μm to 200 V / μm, and preferably 70 V / μm to 150 V / μm.

[0046] In the above formula, α is a constant ranging from 0.4 to 0.9, preferably from 0.6 to 0.85. The smoother the surface roughness of the resulting cured film, the higher the value of α can be. When the surface of the cured film is highly smooth, for example, close to a mirror finish, α can be 0.7 or greater.

[0047] In the above formula, Y is Young's modulus in the range of 0.001 MPa to 10 MPa, preferably 0.001 MPa to 2 MPa, and more preferably 0.001 MPa to 1.5 MPa.

[0048] In the above formula, ε γ is a relative dielectric constant of 100 or less, preferably 50 or less, and more preferably in the range of 1-10.

[0049] The above E, α, Y, and ε γ When the curable elastomer composition has a viscosity within the above range, the cured product of the curable elastomer composition satisfies the mechanical and electrical properties required for an electroactive polymer material used in a transducer device.

[0050] The curable elastomer composition of the present invention is preferably a curable poly(meth)acrylic elastomer composition, a curable polyurethane elastomer composition, or a curable organopolysiloxane elastomer composition, and more preferably a curable organopolysiloxane elastomer composition.

[0051] The highly dielectric functional group of the present invention is not particularly limited, but examples thereof include a) halogen atoms and halogen atom-containing groups typified by a 3,3,3-trifluoropropyl group, etc., b) nitrogen atom-containing groups typified by a cyanopropyl group, etc., c) oxygen atom-containing groups typified by a carbonyl group, etc., d) heterocyclic groups such as an imidazole group, e) boron-containing groups such as a borate ester group, f) phosphorus-containing groups such as a phosphine group, and g) sulfur-containing groups such as a thiol group, and it is preferable to use halogen atoms and halogen atom-containing groups containing a fluorine atom.

[0052] The compound having a highly dielectric functional group of the present invention is not particularly limited as long as it is a compound having a highly dielectric functional group as exemplified above, but examples thereof include organopolysiloxanes or organohydrogenpolysiloxanes having a highly dielectric functional group, organic additives having a highly dielectric functional group, and non-reactive organosilicon compounds having a highly dielectric functional group, with organopolysiloxanes or organohydrogenpolysiloxanes having a highly dielectric functional group and non-reactive organosilicon compounds having a highly dielectric functional group being more preferred.

[0053] The curable elastomer composition is preferably cured by one or more curing reaction mechanisms selected from hydrosilylation reaction curing, condensation reaction curing, radical reaction curing, and high-energy ray curing reaction, and more preferably hydrosilylation reaction curing.

[0054] In one embodiment, the curable elastomeric composition comprises: (A) an organopolysiloxane having a curing reactive group containing at least two carbon-carbon double bonds in the molecule; (B) an organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms in the molecule, and (C) Hydrosilylation reaction catalyst It is preferred that the compound contains:

[0055] The component (A) is an organopolysiloxane having a curing reactive group containing a carbon-carbon double bond, and examples thereof include linear, branched, cyclic, or resinous (network) organopolysiloxanes containing a curing reactive group in the molecule selected from alkenyl groups having 2 to 20 carbon atoms, such as vinyl, allyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, and dodecenyl; acrylic-containing groups, such as 3-acryloxypropyl and 4-acryloxybutyl; and methacrylic-containing groups, such as 3-methacryloxypropyl and 4-methacryloxybutyl. Organopolysiloxanes having a curing reactive group containing a carbon-carbon double bond selected from vinyl, allyl, and hexenyl groups are particularly preferred.

[0056] The organopolysiloxane of component (A) may contain groups selected from monovalent hydrocarbon groups that do not contain a carbon-carbon double bond in the molecule, hydroxyl groups, and alkoxy groups. Furthermore, the monovalent hydrocarbon groups may have some of their hydrogen atoms substituted with halogen atoms or hydroxyl groups. Examples of such monovalent hydrocarbon groups include alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, and dodecyl; aryl groups such as phenyl, tolyl, xylyl, naphthyl, anthracenyl, phenanthryl, and pyrenyl; aralkyl groups such as benzyl, phenethyl, naphthylethyl, naphthylpropyl, anthracenylethyl, phenanthrylethyl, and pyrenylethyl; and groups in which the hydrogen atoms of these aryl or aralkyl groups have been substituted with alkyl groups such as methyl and ethyl; alkoxy groups such as methoxy and ethoxy; or halogen atoms such as chlorine and bromine. When component (A) contains hydroxyl groups, the component exhibits condensation reactivity in addition to hydrosilylation curability.

[0057] Preferably, component (A) has the following average formula: R 1 a R 2 b SiO (4-a―b) / 2 or a mixture thereof. In the formula, R 1 is a curing reactive group containing a carbon-carbon double bond as described above, R 2 is a group selected from the above monovalent hydrocarbon groups having no carbon-carbon double bond, hydroxyl groups, and alkoxy groups, a and b are numbers that satisfy the following conditions: 1≦a+b≦3 and 0.001≦a / (a+b)≦0.33, and preferably the following conditions: 1.5≦a+b≦2.5 and 0.005≦a / (a+b)≦0.2. This is because when a+b is equal to or greater than the lower limit of the above range, the flexibility of the cured product is increased, whereas when it is equal to or less than the upper limit of the above range, the mechanical strength of the cured product is increased;

[0058] In one embodiment, component (A) is particularly preferably (a1) a linear or branched organopolysiloxane having alkenyl groups only at the molecular chain terminals, and optionally (a2) An alkenyl group-containing organopolysiloxane resin having at least one branched siloxane unit in the molecule and having a vinyl (CH2=CH-) group content in the range of 1.0 to 5.0 mass%. or a mixture thereof.

[0059] Component (a1) has a molecular chain terminal (Alk)R 2 2SiO 1 / 2 (wherein Alk is an alkenyl group having 2 or more carbon atoms), and other siloxane units are substantially represented by R 2 2SiO 2 / 2 It is a linear or branched organopolysiloxane consisting only of siloxane units represented by the formula: 2 represents the same group as above. The degree of siloxane polymerization of component (a1), including the terminal siloxane units, is in the range of 7 to 1002, and may be in the range of 102 to 902. Such component (a1) is particularly preferably a compound in which both ends of the molecular chain are (Alk)R 2 2SiO 1 / 2 It is a linear organopolysiloxane terminated with a siloxane unit represented by the formula:

[0060] Component (a2) is an alkenyl group-containing organopolysiloxane resin, and may be used optionally in combination with the above-mentioned component (a1). Such component (a2) is Average unit formula: (RSiO 3 / 2 )o(R2SiO 2 / 2 )p(R3SiO 1 / 2 )q(SiO 4 / 2 )r(XO 1 / 2 )s Examples of the alkenyl group-containing organopolysiloxane resin include those represented by the following formula: In the above formula, R is a group selected from an alkenyl group and the monovalent hydrocarbon group not having a carbon-carbon double bond, and X is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. However, among all R, at least R is an alkenyl group in the range in which the content of vinyl (CH2=CH-) groups in the organopolysiloxane resin is in the range of 1.0 to 5.0 mass%, and in particular RSiO 1 / 2 Preferably, at least some of the R on the siloxane unit represented by the formula: is an alkenyl group.

[0061] In the above formula, (o+r) is a positive number, p is 0 or a positive number, q is 0 or a positive number, s is 0 or a positive number, and p / (o+r) is a number within the range of 0 to 10, q / (o+r) is a number within the range of 0 to 5, (o+r) / (o+p+q+r) is a number within the range of 0.3 to 0.9, and s / (o+p+q+r) is a number within the range of 0 to 0.4.

[0062] As component (a2), particularly preferred are {(Alk)R 2 2SiO 1 / 2}q1(R 2 3SiO 1 / 2 )q2(SiO 4 / 2 )r (Wherein Alk and R 2is the same group as above, q1 + q2 + r is a number in the range of 50 to 500, (q1 + q2) / r is a number in the range of 0.1 to 2.0, and q2 is a number in the range such that the content of vinyl (CH2=CH-) groups in the organopolysiloxane resin is in the range of 1.0 to 5.0 mass%. Examples include alkenyl group-containing MQ organopolysiloxane resins represented by the following formula:

[0063] By using component (a1) having alkenyl groups only at the molecular chain terminals in combination with component (a2), an organopolysiloxane resin having a certain amount of alkenyl groups as needed, the composition as a whole has excellent curability, and a cured reaction product having excellent mechanical strength and flexibility can be obtained, making it possible to provide an organopolysiloxane cured film that is particularly suitable for adhesive layers or dielectric layers in the above-mentioned electronic components, etc.

[0064] Component (B) is an organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms in the molecule, and functions as a crosslinking agent for component (A).

[0065] Examples of such component (B) include 1,1,3,3-tetramethyldisiloxane, 1,3,5,7-tetramethylcyclotetrasiloxane, tris(dimethylhydrogensiloxy)methylsilane, tris(dimethylhydrogensiloxy)phenylsilane, methylhydrogenpolysiloxane terminated at both molecular chain ends with trimethylsiloxy groups, dimethylsiloxane-methylhydrogensiloxane copolymer terminated at both molecular chain ends with trimethylsiloxy groups, and dimethylhydrogenpolysiloxane terminated at both molecular chain ends with trimethylsiloxy groups. Hydrogensiloxy-capped dimethylpolysiloxane, dimethylhydrogensiloxy-terminated dimethylsiloxane-methylhydrogensiloxane copolymer at both molecular chain ends, methylhydrogensiloxane-diphenylsiloxane copolymer at both molecular chain ends, methylhydrogensiloxane-diphenylsiloxane-dimethylsiloxane copolymer at both molecular chain ends, trimethylsiloxy-terminated methylhydrogensiloxane-diphenylsiloxane-dimethylsiloxane copolymer, hydrolysis condensate of trimethoxysilane, (CH3)2HSiO 1 / 2 Units and SiO4 / 2 A copolymer consisting of (CH3)2HSiO units 1 / 2 Units and SiO 4 / 2 Units and (C6H5)SiO 3 / 2 Examples include copolymers consisting of these units and mixtures of two or more of these units.

[0066] The amount of component (B) used in the composition is such that the number of silicon-bonded hydrogen atoms is in the range of 0.1 to 10 moles per mole of carbon-carbon double bonds in component (A), preferably 0.1 to 5.0 moles, and particularly preferably 0.1 to 2.5 moles. Using component (B) in an amount below the lower limit may result in poor curing, while using component (B) in an amount above the upper limit may result in the cured product having too high a mechanical strength, making it impossible to achieve suitable physical properties for an adhesive layer or dielectric layer. However, when the objective is to improve the adhesive strength of the organopolysiloxane cured film of the present invention to an adherend such as glass, use in an amount greater than 20 moles of silicon-bonded hydrogen atoms per mole of carbon-carbon double bonds in component (A) is not precluded.

[0067] Component (C) is a catalyst that promotes the hydrosilylation reaction of components (A) and (B), and examples thereof include platinum-based catalysts, rhodium-based catalysts, palladium-based catalysts, nickel-based catalysts, iridium-based catalysts, ruthenium-based catalysts, and iron-based catalysts, with a platinum-based catalyst being preferred. Examples of platinum-based catalysts include platinum fine powder, platinum black, platinum-supported silica fine powder, platinum-supported activated carbon, chloroplatinic acid, alcohol solutions of chloroplatinic acid, platinum olefin complexes, and platinum alkenylsiloxane complexes, with a platinum alkenylsiloxane complex being particularly preferred. Examples of this alkenylsiloxane include 1,3-divinyl-1,1,3,3-tetramethyldisiloxane, 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane, alkenylsiloxanes in which some of the methyl groups of these alkenylsiloxanes have been substituted with ethyl groups, phenyl groups, etc., and alkenylsiloxanes in which the vinyl groups of these alkenylsiloxanes have been substituted with allyl groups, hexenyl groups, etc. 1,3-divinyl-1,1,3,3-tetramethyldisiloxane is particularly preferred because the platinum-alkenylsiloxane complex has good stability. Furthermore, it is preferable to add to the platinum-alkenylsiloxane complex an alkenylsiloxane such as 1,3-divinyl-1,1,3,3-tetramethyldisiloxane, 1,3-diallyl-1,1,3,3-tetramethyldisiloxane, 1,3-divinyl-1,3-dimethyl-1,3-diphenyldisiloxane, 1,3-divinyl-1,1,3,3-tetraphenyldisiloxane, or 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane, as well as an organosiloxane oligomer such as a dimethylsiloxane oligomer, because this can improve the stability of the platinum-alkenylsiloxane complex. Addition of an alkenylsiloxane is particularly preferable. In addition, from the standpoint of improving handling ease and the pot life of the composition, these hydrosilylation catalysts may be in the form of hydrosilylation catalyst-containing thermoplastic resin fine particles, in particular, thermoplastic resin fine particles containing a platinum-containing hydrosilylation catalyst, which are catalysts dispersed or encapsulated in a thermoplastic resin such as a silicone resin, a polycarbonate resin, or an acrylic resin.As a catalyst for promoting the hydrosilylation reaction, a non-platinum metal catalyst such as iron, ruthenium, or iron / cobalt may also be used.

[0068] The amount of component (C) used is an effective amount, and is not particularly limited, as long as it promotes curing of the curable organopolysiloxane composition of the present invention. Specifically, the amount is such that the metal atoms in the catalyst are 0.01 to 1,0000 ppm by mass, and preferably the platinum metal atoms in component (C) are 0.1 to 5,000 ppm, based on the sum of components (A) to (C) (total being 100% by mass). If the content of component (C) is below the lower limit of the above range, curing may be insufficient, while if it exceeds the upper limit of the above range, it may be uneconomical and may have adverse effects on the transparency, such as coloration, of the resulting cured product.

[0069] In one embodiment, the organopolysiloxane or organohydrogenpolysiloxane having a highly dielectric functional group is particularly preferably a part or all of component (A) or component (B).

[0070] In the organopolysiloxane or organohydrogenpolysiloxane of component (A) or component (B), it is preferred that 10 mol % or more, preferably 20 mol % or more, and more preferably 40 mol % or more of all substituents on the silicon atoms are substituted with highly dielectric functional groups. By adjusting the amount of highly dielectric functional groups introduced, it is possible to obtain optimal miscibility with the curable elastomer composition and the relative dielectric constant (ε γ ) can be obtained.

[0071] In one embodiment, a part or all of component (A) or component (B) of the curable elastomer composition contains (C p F 2p+1 Preferably, the organopolysiloxane or organohydrogenpolysiloxane has a fluoroalkyl group represented by the formula: )-R- (R is an alkylene group having 1 to 10 carbon atoms, and p is an integer of 1 or more and 8 or less).

[0072] The above-mentioned fluoroalkyl groups provide cured products with excellent dielectric constants, and the fluorine atoms in each component improve the compatibility of the components, resulting in cured products with excellent transparency. Specific examples of such fluoroalkyl groups include trifluoropropyl, pentafluorobutyl, heptafluoropentyl, nonafluorohexyl, undecafluoroheptyl, tridecafluorooctyl, pentadecafluorononyl, and heptadecafluorodecyl. Among these, the group where p=1, i.e., the trifluoropropyl group, is preferred from the viewpoints of dielectric properties, economy, ease of production, and moldability of the resulting curable organopolysiloxane composition.

[0073] In addition to the above-mentioned components, other components may be added to the curable elastomer composition of the present invention as needed, provided that the addition does not impair the objectives of the present invention. Examples of other components include solvents (D), hydrosilylation reaction inhibitors (E), fillers (F), mold release agents, insulating additives, adhesion improvers (G), heat resistance improvers, pigments, and various other conventional additives. For example, inorganic fillers may be added to adjust the overall viscosity or to improve functionality, such as dielectric properties.

[0074] [Solvent (D)] When the curable elastomer composition is solid or highly viscous, the organic solvent or a mixture thereof is used for the purposes of improving the miscibility and handling properties of the curable elastomer composition, dispersing it uniformly, reducing the overall viscosity, and forming a thin, uniform film. If a non-polar solvent such as benzene is used, the technical effects of the present invention may not be fully realized, and the curable elastomer composition may not be uniformly dispersed, making it impossible to achieve a low viscosity.

[0075] Such organic solvents include (D1) organic polar solvent, (D2) a low molecular weight siloxane solvent, and (D3) Halogenated solvents The solvent is preferably one or more organic solvents selected from the group consisting of (D1) and (D2), or a mixture thereof, having a boiling point of 80°C or higher but lower than 200°C. Mixed solvents of different or the same organic solvents in any ratio may also be used. For example, the solvent may be a mixed solvent of (D1) an organic polar solvent and (D2) a low molecular weight siloxane-based solvent, a mixed solvent of (D1) an organic polar solvent and (D3) a halogen-based solvent, a mixed solvent of (D2) a low molecular weight siloxane-based solvent and (D3) a halogen-based solvent, a mixed solvent of three of (D1) to (D3), or a mixed solvent of the same type, such as a mixed solvent of hexamethyldisiloxane and octamethyltrisiloxane, both of which are (D2) low molecular weight siloxane-based solvents. These organic solvents can be selected appropriately depending on the curable elastomer composition.

[0076] Preferably, the (D1) organic polar solvent is one or more selected from cyclohexanone, isobutyl acetate, methyl ethyl ketone, methyl butyl ketone, methyl isobutyl ketone, N,N-dimethylformamide (DMF), N-hexaldehyde, acetone, benzaldehyde, methyl acetate, propyl acetate, acetophenone, pentyl acetate, butyraldehyde, ethyl methyl acetate, ethyl ether, and tetrahydrofuran (THF).

[0077] Similarly, (D2) the low molecular weight siloxane solvent is preferably one or more selected from hexamethyldisiloxane, tetramethyldivinyldisiloxane, 2-methylphenethylpentamethyldisiloxane, octamethyltrisiloxane, and 1,3-difluorotetramethyldisiloxane.

[0078] Similarly, the halogenated solvent (D3) is preferably one or more selected from trifluoromethylbenzene, 1,2-bis(trifluoromethyl)benzene, 1,3-bis(trifluoromethyl)benzene, 1,4-bis(trifluoromethyl)benzene, trifluoromethylchlorobenzene, trifluoromethylfluorobenzene, and hydrofluoroether. In particular, the higher the content of highly dielectric functional groups in the curable elastomer composition, the more likely it is that uniform mixing and lower viscosity can be achieved by increasing the proportion of the halogenated solvent used.

[0079] Particularly preferably, the organic solvent comprises at least one low molecular weight siloxane solvent selected from hexamethyldisiloxane and octamethyltrisiloxane, or a mixture thereof, which are commercially available from Dow Silicones Corporation under the names OST-10, OST-20, and OST-2. In addition, when the fluoroalkyl group content in the curable elastomer composition is high, optionally using these low molecular weight siloxane solvents in combination with the above-mentioned halogen-containing solvents is also encompassed within a preferred embodiment of the present invention.

[0080] [Hydrosilylation Reaction Inhibitor (E)] The hydrosilylation reaction inhibitor (E) is added to inhibit the crosslinking reaction that occurs between component (A) and component (B), thereby extending the usable time at room temperature and improving storage stability.

[0081] Examples of the hydrosilylation reaction inhibitor (E) include acetylene compounds, enyne compounds, organic nitrogen compounds, organic phosphorus compounds, and oxime compounds.Specific examples include alkyne alcohols such as 3-methyl-1-butyn-3-ol, 3,5-dimethyl-1-hexyn-3-ol, 3-methyl-1-pentyn-3-ol, 1-ethynyl-1-cyclohexanol, and phenylbutynol; enyne compounds such as 3-methyl-3-penten-1-yne and 3,5-dimethyl-1-hexyn-3-yne; methylalkenylcyclosiloxanes such as 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane and 1,3,5,7-tetramethyl-1,3,5,7-tetrahexenylcyclotetrasiloxane; and benzotriazole.

[0082] The amount of hydrosilylation reaction inhibitor (E) added is an amount effective for extending the usable life of the curable elastomer composition of the present invention at room temperature and improving its storage stability. It is usually 0.001 to 5 parts by mass, preferably 0.01 to 2 parts by mass, per 100 parts by mass of component (A), but this amount can be selected appropriately depending on the type of component, the performance and content of the platinum-based catalyst, the amount of alkenyl groups in component (A), and the amount of silicon-bonded hydrogen atoms in component (B), among other factors.

[0083] Filler In the curable elastomer composition of the present invention, a filler (F) may or may not be used as desired. When a filler (F) is used, either an inorganic filler or an organic filler, or both, may be used. The type of filler (F) used is not particularly limited, and examples thereof include highly dielectric fillers, conductive fillers, insulating fillers, and reinforcing fillers, and one or more of these may be used. In particular, the composition of the present invention may contain one or more fillers (F) selected from the group consisting of highly dielectric fillers, conductive fillers, insulating fillers, and reinforcing fillers for the purpose of adjusting viscosity or imparting functionality, within a range that does not impair the transparency, coatability, and handling properties. In particular, it is preferable to incorporate at least one reinforcing filler from the viewpoint of improving mechanical strength. In particular, a portion or all of the filler (F) may be surface-treated with one or more surface treatment agents.

[0084] The filler (F) may be one or more types, and its shape is not particularly limited, and any shape, such as particulate, plate-like, needle-like, or fibrous, can be used. When the filler is particulate, the particle size of the filler is not particularly limited, but the volume average particle size, as measured by laser light diffraction or dynamic light scattering, can be, for example, in the range of 0.001 to 500 μm. Depending on the purpose of use of the filler, the volume average particle size of the filler can be 300 μm or less, 200 μm or less, 100 μm or less, or 0.01 μm or more, 0.1 μm or more, or 1 μm or more. When the filler has an anisotropic shape, such as a plate-like, needle-like, or fibrous shape, the aspect ratio of the filler can be 1.5 or more, 5 or more, or 10 or more. When fine particles having a volume average particle size of 0.01 μm or less and a maximum particle size of 0.02 μm or less are used, it may be possible to produce cured products, particularly adhesive films or electroactive films, with substantially high transparency.

[0085] [Reinforcing filler] In the present invention, from the viewpoint of the mechanical strength of the cured product, the preferred reinforcing filler is one or more types of reinforcing inorganic fine particles having an average primary particle size of less than 50 nm, and examples thereof include fumed silica, wet silica, pulverized silica, calcium carbonate, diatomaceous earth, finely pulverized quartz, various metal oxide powders other than alumina and zinc oxide, glass fiber, and carbon fiber. These may also be treated with various surface treatment agents described below. Of these, silica is recommended.

[0086] A good example is a powder with an average primary particle size of 10 nm or less, partially aggregated, and a specific surface area of ​​50 m 2 / g or more, 300m 2 Examples of suitable reinforcing inorganic particles include hydrophilic or hydrophobic fumed silica or its metal oxide composites, each having a specific surface area of ​​1 / g or less. Furthermore, from the viewpoint of improving dispersibility, fumed silica or its metal oxide composites treated with hexamethyldisilazane, or a disilazane having a highly dielectric functional group, such as 1,3-bis(3,3,3-trifluoropropyl)-1,1,3,3-tetramethyldisilazane, or a silane coupling agent, which will be described later, are preferred. Two or more of these reinforcing inorganic particles may be used in combination.

[0087] The incorporation of filler (F) into the composition can increase the mechanical strength and dielectric breakdown strength of the cured product obtained by curing the curable elastomer composition of the present invention. The amount of filler (F) incorporated is within the range of 10 to 40 mass %, or alternatively, 15 to 35 mass %, with 15 to 30 mass % being particularly preferred, based on the sum of the components in the composition that form nonvolatile solids upon curing reaction. If the amount exceeds the upper limit of the above mass % range, it may be difficult to apply a uniform, thin film. If the amount is below the lower limit of the above mass % range, the cured physical properties of the curable elastomer composition may be insufficient.

[0088] Some or all of the inorganic fine particles (regardless of particle size, function, etc.) used in the curable elastomer composition of the present invention may be surface-treated with one or more surface treatment agents. The type of surface treatment is not particularly limited, and examples include hydrophilic treatment and hydrophobic treatment, with hydrophobic treatment being preferred. The use of hydrophobically treated inorganic fine particles allows them to be dispersed in the composition at a high filling rate. Furthermore, an increase in the viscosity of the composition is suppressed, improving moldability.

[0089] The surface treatment can be carried out by treating (or coating) inorganic fine particles with a surface treatment agent. Examples of surface treatment agents for hydrophobization include at least one surface treatment agent selected from the group consisting of organotitanium compounds, organosilicon compounds, organozirconium compounds, organoaluminum compounds, and organophosphorus compounds. The surface treatment agents may be used alone or in combination of two or more. Among these surface treatment agents, organosilicon compounds, particularly silazanes, silanes, siloxanes, and polysiloxanes, are preferred, with silazanes, alkyltrialcosiloxanes, and one-terminal trialcosilylpolydimethylsiloxanes being most preferred.

[0090] In the surface treatment, the ratio of the surface treatment agent to the total amount of filler is preferably in the range of 0.1% by mass or more and 50% by mass or less, and more preferably in the range of 0.3% by mass or more and 30% by mass or less. The treatment amount is the ratio of the filler to the surface treatment agent, and it is preferable to remove excess treatment agent after treatment. Furthermore, additives that promote or assist the reaction may be used during treatment as necessary.

[0091] [Other functional fillers] Examples of other functional fillers include dielectric inorganic fine particles, conductive inorganic fine particles, insulating inorganic fine particles, and thermally conductive inorganic fine particles. One or more types selected from these fine particles can be used in the composition of the present invention. These inorganic fine particles may have two or more functions, such as a function as a reinforcing filler.

[0092] Preferred examples of dielectric inorganic fine particles include one or more inorganic fine particles selected from the group consisting of titanium oxide, barium titanate, strontium titanate, lead zirconate titanate, and composite metal oxides in which part of the barium and titanium moieties of barium titanate are substituted with alkaline earth metals or rare earth metals such as calcium, strontium, yttrium, neodymium, samarium, dysprosium, or zirconium, with titanium oxide, barium titanate, barium calcium zirconate titanate, and strontium titanate being more preferred, and titanium oxide and barium titanate being even more preferred.

[0093] In particular, it is particularly preferred that at least a portion of the dielectric inorganic fine particles have a relative dielectric constant of 10 or more at room temperature and 1 kHz. The preferred upper limit of the size (average primary particle diameter) of the inorganic fine particles is 20,000 nm (20 μm), but in consideration of the processability into thin films for transducers described below, 10,000 nm (10 μm) is more preferred. The use of such dielectric inorganic fine particles may further improve the mechanical properties and / or electrical properties, particularly the relative dielectric constant, of the cured product of the curable elastomer composition.

[0094] The conductive inorganic fine particles are not particularly limited as long as they can impart conductivity to the cured product of the curable elastomer composition. Specific examples include conductive carbons such as conductive carbon black, graphite, and vapor-grown carbon (VGCF); metal powders such as platinum, gold, silver, copper, nickel, tin, zinc, iron, and aluminum; antimony-doped tin oxide, phosphorus-doped tin oxide, acicular titanium oxide coated with tin oxide / antimony, tin oxide, indium oxide, antimony oxide, zinc antimonate; pigments in which the surface of carbon or graphite whiskers is coated with tin oxide or the like; pigments in which at least one conductive metal oxide selected from the group consisting of tin-doped indium oxide (ITO), fluorine-doped tin oxide (FTO), phosphorus-doped tin oxide, and nickel oxide is coated; and conductive titanium dioxide particles containing tin oxide and phosphorus on the surface. These may also be treated with various surface treatment agents, as described below. These may be used alone or in combination of two or more.

[0095] Furthermore, the conductive inorganic fine particles may be fibers such as glass fibers, silica alumina fibers, alumina fibers, and carbon fibers, needle-shaped reinforcing materials such as aluminum borate whiskers and potassium titanate whiskers, and inorganic fillers such as glass beads, talc, mica, graphite, wollastonite, and dolomite, the surfaces of which are coated with a conductive material such as a metal.

[0096] The insulating inorganic fine particles that can be used in the present invention are generally known insulating inorganic materials, i.e., those having a volume resistivity of 10 10 ~10 18There are no limitations on the inorganic particles, as long as they have a resistivity of Ω·cm. They can be in any form, including particles, flakes, or fibers (including whiskers). Specific examples include spherical, plate-like, or fibrous ceramic particles. Preferred examples include particles of alumina, iron oxide, copper oxide, metal silicates such as mica and talc, quartz, amorphous silica, and glass. These may also be treated with the various surface treatment agents described below. These may be used alone or in combination. The incorporation of insulating inorganic fine particles into the composition can increase the mechanical strength and dielectric breakdown strength of the cured product of the curable elastomer composition, and may also result in an increase in the dielectric constant.

[0097] The amount of the insulating inorganic particles to be added is preferably 0.1 to 20% by mass, more preferably 0.1 to 5% by mass, of the curable elastomer composition depending on the intended use. If the amount is outside the above-mentioned preferred range, the effect of the addition may not be obtained, or the mechanical strength of the cured product of the curable elastomer composition may decrease.

[0098] Thermally conductive inorganic fine particles that can be used in the present invention include metal oxide particles such as magnesium oxide, zinc oxide, nickel oxide, vanadium oxide, copper oxide, iron oxide, and silver oxide, as well as inorganic compound particles such as aluminum nitride, boron nitride, silicon carbide, titanium carbide, diamond, and diamond-like carbon, with zinc oxide, boron nitride, silicon carbide, and silicon nitride being preferred. By incorporating one or more of these thermally conductive inorganic fine particles into the composition, it is possible to increase the thermal conductivity of the cured product of the curable elastomer composition.

[0099] The average particle size of these inorganic particles can be measured by a measurement method commonly used in the art. For example, when the average particle size is 50 nm or more and approximately 500 nm or less, the average primary particle size can be measured by measuring the particle size through microscopic observation using a transmission electron microscope (TEM), field emission transmission electron microscope (FE-TEM), scanning electron microscope (SEM), field emission scanning electron microscope (FE-SEM), or the like, and calculating the average value. On the other hand, when the average particle size is approximately 500 nm or more, the average primary particle size can be directly calculated using a laser diffraction / scattering particle size distribution analyzer or the like.

[0100] These inorganic particles may be hydrophobized with a surface treatment agent. The surface treatment can be carried out by treating (or coating) the filler with the surface treatment agent. Examples of the surface treatment agent for hydrophobization include at least one surface treatment agent selected from the group consisting of organotitanium compounds, organosilicon compounds, organozirconium compounds, organoaluminum compounds, and organophosphorus compounds. The surface treatment agents may be used alone or in combination of two or more. Among these surface treatment agents, organosilicon compounds, particularly silazanes, silanes, siloxanes, and polysiloxanes, are preferred, with silazanes, alkyltrialcosilanes, and one-terminal trialcosilyl polydimethylsiloxanes being preferred. The treatment amount, etc., are the same as the treatment method and treatment amount, etc., described above for the surface treatment of the filler component.

[0101] [Other optional ingredients] The curable elastomer composition according to the present invention may further contain additives for improving mold releasability or dielectric breakdown properties, adhesion improvers, and the like.

[0102] The film- or sheet-like cured product obtained by curing the curable elastomer composition according to the present invention into a thin film can be suitably used as an adhesive film and an electroactive film (dielectric layer or electrode layer) constituting a transducer. However, if the release properties of the cured layer during thin film formation are poor, the film may be damaged due to release from the mold, especially when the film is produced at high speed. Furthermore, dielectric layers used in actuators and touch panels may require reduced adhesiveness to improve sensitivity under low pressure. The curable elastomer composition according to the present invention can increase the film production speed without damaging the film, and the addition of other release agents may further reduce adhesion.

[0103] Examples of mold release property improving additives (i.e., mold release agents) that can be used in the curable elastomer composition of the present invention include carboxylic acid-based mold release agents, ester-based mold release agents, ether-based mold release agents, ketone-based mold release agents, and alcohol-based mold release agents. These may be used alone or in combination of two or more. The mold release agents may be silicon-free, silicon-containing, or a mixture thereof. Specific examples of these agents are similar to those proposed in, for example, WO 2014 / 105959.

[0104] The dielectric breakdown characteristic improver is preferably an electrical insulation improver, and may be selected from the group consisting of aluminum or magnesium hydroxides or salts, clay minerals, and mixtures thereof, specifically aluminum silicate, aluminum sulfate, aluminum hydroxide, magnesium hydroxide, calcined clay, montmorillonite, hydrotalcite, talc, and mixtures thereof. The insulation improver may also be treated by a known surface treatment method. Specific examples of these are similar to those proposed in WO 2014 / 105959.

[0105] The adhesion improver (G) is used to improve the adhesion of the curable elastomer composition of the present invention to a substrate with which it comes into contact during curing. It is an effective additive when the dielectric layer, which is the cured product of the composition, is not to be removed again. Examples of adhesion improvers include organofunctional alkoxysilane compounds such as vinyltriethoxysilane, allyltrimethoxysilane, allyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, and 3-methacryloxypropyltrimethoxysilane, and siloxane derivatives thereof, particularly linear or three-dimensional resinous siloxane derivatives substituted with fluorine-containing organic groups. Particularly preferred adhesion improvers include: (g1) Reaction mixture of amino group-containing organoalkoxysilane and epoxy group-containing organoalkoxysilane (g2) An organic compound having at least two alkoxysilyl groups in one molecule and containing a bond other than a silicon-oxygen bond between the silyl groups. (g3) General formula: R a n Si(OR b ) 4-n (In the formula, R a is a monovalent epoxy-containing organic group, and R b is an alkyl group having 1 to 6 carbon atoms or a hydrogen atom, and n is a number ranging from 1 to 3. or a partial hydrolysis condensate thereof (g4) Alkoxysilanes (excluding those having epoxy-containing organic groups) or their partial hydrolysis condensates Examples include one or more selected from the following:

[0106] Examples of other optional components, provided they do not impair the technical effects of the present invention, include antioxidants such as phenols, quinones, amines, phosphorus, phosphite, sulfur, and thioethers; light stabilizers such as triazoles and benzophenones; flame retardants such as phosphate esters, halogens, phosphorus, and antimony; one or more antistatic agents such as cationic surfactants, anionic surfactants, and nonionic surfactants; dyes, and pigments.

[0107] In one embodiment, the curable elastomeric composition of the present invention is preferably for use in a transducer device.

[0108] [Cured product] The present invention also relates to a cured product of the curable elastomer composition of the present invention. The Young's modulus Y of the cured product of the present invention is 0.001 MPa to 10 MPa, preferably 0.001 MPa to 2 MPa, and more preferably 0.001 MPa to 1.5 MPa. The relative dielectric constant ε of the cured product of the present invention is γ is not more than 100, preferably not more than 50, and more preferably in the range of 1 to 10. When the cured product falls within the above range, it is possible to obtain an optimal cured product of the curable elastomer that has mechanical properties and electrical properties suitable for forming a transducer device.

[0109] The cured product of the curable elastomer composition of the present invention can be prepared by uniformly mixing preferably the curable organopolysiloxane and the curing reaction accelerator, more preferably the above-mentioned components (A) to (C), and by adding other optional components as necessary, mixing them uniformly, and then causing a curing reaction.

[0110] The components may be mixed at room temperature using various types of stirrers or kneaders, but they may also be mixed under heat if the combination of components does not harden during mixing. The order in which the components are mixed is not particularly limited as long as they do not harden during mixing. If the mixture is not to be used immediately after mixing, it is possible to store the components in multiple containers so that the crosslinking agent (e.g., component (B)) and the component that accelerates the hardening reaction (e.g., component (C)) are not contained in the same container, and then mix the components in all containers immediately before use.

[0111] The curing reaction of the curable elastomer composition of the present invention, which is based on a condensation reaction such as dehydration and dealcoholization, proceeds at room temperature. However, when producing an organopolysiloxane cured film using an industrial production process, the composition is typically heated or exposed to active energy rays. The temperature for the thermal curing reaction is not particularly limited, but is preferably 50°C to 200°C, more preferably 60°C to 200°C, and even more preferably 80°C to 180°C. The time required for the curing reaction depends on the structure of the above-mentioned components (A), (B), and (C), but is typically 1 second to 3 hours. In general, a cured product can be obtained by maintaining the temperature within the range of 90 to 180°C for 10 seconds to 30 minutes.

[0112] Examples of active energy rays that can be used in the curing reaction include ultraviolet rays, electron beams, and radioactive rays, with ultraviolet rays being preferred from the viewpoint of practicality. When the curing reaction is carried out using ultraviolet rays, it is desirable to add a hydrosilylation reaction catalyst that has high activity against the ultraviolet rays used, such as bis(2,4-pentanedionato)platinum complex and (methylcyclopentadienyl)trimethylplatinum complex. Suitable sources of ultraviolet rays include high-pressure mercury lamps, medium-pressure mercury lamps, Xe-Hg lamps, and deep UV lamps, and the irradiation dose in this case is 100 to 8,000 mJ / cm. 2 is preferred.

[0113] [Electronic parts or display devices] The present invention also relates to an electronic component or display device having the cured product of the present invention. The electronic component and display device of the present invention are preferably electronic materials, particularly transducer members (including those for sensors, speakers, actuators, and generators).

[0114] [film] The present invention also relates to a film comprising the cured product of the present invention.

[0115] [Thickness, uniformity and flatness] The film of the present invention is thin and has an average thickness preferably in the range of 0.1 to 200 μm, more preferably in the range of 0.1 to 150 μm, and even more preferably in the range of 0.1 to 100 μm. Here, the average thickness of the film is the average value of the thickness at the center of the film. Preferably, the film of the present invention is uniform and flat, with the difference between the thickness at the end and the center in the width direction of the film being within 5.0% and the average thickness at the center of the film being more preferably in the range of 5 to 200 μm. The width direction of the film is the direction perpendicular to the length direction of the film, and generally refers to the direction perpendicular to the planar direction of the direction in which the raw material curable elastomer composition is applied to the substrate. When the film is wound up, the direction of winding is the length direction, and the width direction of the film is the direction perpendicular to that. In a quadrilateral or approximately quadrilateral film, the width direction of the film is the direction perpendicular to the long axis direction, and in a square or approximately square film, the width direction may be either perpendicular to or parallel to each side of the square film.

[0116] The film of the present invention has a difference (absolute value) between the thickness (μm) at the end and the thickness (μm) at the center in the width direction of the film of 5.0% or less, preferably 4.0% or less, and particularly preferably 3.5% or less. The film preferably has a flat and uniform structure with substantially no irregularities on the surface, including protrusions at both ends. The maximum thickness variation (difference) in the film width direction is preferably 5.0% or less, and the maximum thickness variation (difference) throughout the film is particularly preferably 5.0% or less, making it a flat film with substantially no irregularities. A flat film has the advantage that it is less susceptible to bubble entrapment, deformation, and defects due to irregularities between films, not only when a single film layer but also multiple film layers are superimposed to form a uniform, thick film layer.

[0117] The film of the present invention has an average thickness of 0.1 to 200 μm per sheet, but it is also possible to form a laminated film having a thickness of more than 200 μm by stacking multiple films and use it for the purpose of forming an adhesive layer or a dielectric layer. In particular, a dielectric film constituting a dielectric layer formed by stacking two or more of the films is included in the scope of the present invention.

[0118] [Film size] The film of the present invention preferably has a certain size (area), and the film width is 30 mm or more, and the film area is 900 mm or more. 2 It is preferable that the film is 30 mm square or larger. Such a film is, for example, a film of 30 mm square or larger. On the other hand, the film of the present invention may have a structure in which the raw material curable composition is uniformly applied and cured even on the release layer, so that the film can be used without any limitation in the length direction as long as it is long enough to be wound on a roll. Needless to say, the film may be cut to a desired size and shape before use.

[0119] [Dielectric breakdown strength] The dielectric breakdown strength of the film of the present invention can be measured using rigid electrodes by the above-mentioned method. In order to avoid variations in the measured values ​​of dielectric breakdown strength at any point on the film, it is preferable to measure the dielectric breakdown strength at at least 10 or more arbitrary points on the film and ensure that the standard deviation is sufficiently small.

[0120] Specifically, the dielectric breakdown strength of the film of the present invention measured at room temperature is in the range of 50 V / μm to 200 V / μm, preferably in the range of 70 V / μm to 150 V / μm. When the film of the present invention is uniform throughout and contains almost no microscopic defects, the standard deviation of the dielectric breakdown strength is sufficiently small, in the range of 0.1 to 10.0 V / μm, preferably in the range of 0.1 to 5.0 V / μm. When the number of defects on the surface and inside of the film is large, the number of defects on the surface and inside of the film also varies greatly, and the standard deviation of the dielectric breakdown strength often exceeds 10.0 V / μm, resulting in a decrease in the reliability of the resulting film.

[0121] [Dielectric constant] The film of the present invention can be easily designed to have a dielectric constant of 100 or less at 1 kHz and 25°C for the entire film. The dielectric constant can be designed by the amount of highly dielectric functional group introduced and the use of a highly dielectric filler, and a film with a dielectric constant of 50 or less, or 1 to 10, can be obtained.

[0122] [Mechanical properties] The macroscopic mechanical properties of the film of the present invention, such as hardness, tear strength, and tensile strength, are generally comparable to those of a film designed with a similar chemical composition, thickness, and shape. For example, when the cured product of the present invention is thermoformed into a 2.0 mm thick sheet, it can be designed to have the following mechanical properties measured according to JIS K 6249: (1) The Young's modulus (MPa) at room temperature can be set to 0.001 to 10 MPa, preferably 0.001 to 2 MPa, and particularly preferably 0.001 to 1.5 MPa. (2) The tear strength (N / mm) can be set to 1 N / mm or more at room temperature, and a particularly preferred range is 2 N / mm or more. (3) The tensile strength (MPa) at room temperature can be 1 MPa or more, and a particularly preferred range is 2 MPa or more. (4) The elongation at break (%) can be 200% or more, and a particularly preferred range is 200 to 1000%.

[0123] When the film of the present invention is used as an electronic material such as a touch panel, an electronic component for a display device, and particularly as a transducer material for a sensor, the film should have a shear storage modulus of 10 at 23°C. 3 ~10 5 Pa, and preferably in the range of 1.0 x 10 3 ~5.0×10 4 It is more preferable that the viscosity is in the range of Pa.

[0124] As for other mechanical properties, the film of the present invention preferably has a compressive set (%) of less than 10%, more preferably less than 5%, and particularly preferably 4% or less, although it is also possible to design a film of the present invention using a material with a compressive set (%) of less than 3%.

[0125] [Laminate] The present invention also relates to a laminate comprising the film of the present invention and a release layer. Preferably, the laminate is a film comprising the cured product of the present invention, releasably laminated on a film substrate comprising a release layer having release coating capability.

[0126] [Method of manufacturing laminate] The present invention also relates to a method for producing a laminate, comprising the steps of: applying the curable elastomer composition of the present invention onto a separator having a release layer in the form of a thin film having a thickness after curing of 1 to 1000 μm, preferably 1 to 200 μm, and more preferably 1 to 100 μm; and curing the curable elastomer composition applied in the form of a thin film.

[0127] The laminate of the present invention can be formed on the surface of a film-like substrate, a tape-like substrate, or a sheet-like substrate (hereinafter referred to as "film-like substrate") by applying the curable elastomer composition to the substrate and then curing the composition by a method corresponding to the curing mechanism of the substrate.

[0128] The substrate is preferably a planar substrate having a release surface, and the curable elastomer composition is applied to the release surface. Such a substrate functions as a separator, and the film of the present invention laminated on the substrate can be easily peeled off from the release layer with a slight force and attached or adhered to the target electronic device, etc., thereby providing the advantage of excellent handling and workability.

[0129] Examples of substrates include paperboard, corrugated cardboard, clay-coated paper, polyolefin-laminated paper, particularly polyethylene-laminated paper, synthetic resin films and sheets, natural fiber fabrics, synthetic fiber fabrics, artificial leather fabrics, and metal foils. Synthetic resin films and sheets are particularly preferred, and examples of synthetic resins include polyimide, polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polycarbonate, polyethylene terephthalate, and nylon. When heat resistance is particularly required, films of heat-resistant synthetic resins such as polyimide, polyether ether ketone, polyethylene naphthalate (PEN), liquid crystal polyarylate, polyamide imide, and polyether sulfone are suitable. On the other hand, for applications requiring visibility, such as display devices, transparent substrates, specifically transparent materials such as polypropylene, polystyrene, polyvinylidene chloride, polycarbonate, polyethylene terephthalate, and PEN, are suitable.

[0130] The substrate is preferably in the form of a film or sheet. Its thickness is not particularly limited, but is usually about 5 to 300 μm. Furthermore, to improve the adhesion between the support film and the pressure-sensitive adhesive layer, a support film that has been subjected to a primer treatment, corona treatment, etching treatment, or plasma treatment may be used. The surface of the film substrate opposite the pressure-sensitive adhesive layer may also be subjected to a surface treatment such as scratch resistance, stain resistance, fingerprint resistance, anti-glare, anti-reflection, and anti-static treatment.

[0131] The curable elastomer composition of the present invention can be applied to a substrate without limitation by gravure coating, offset coating, offset gravure coating, roll coating using an offset transfer roll coater or the like, reverse roll coating, air knife coating, curtain coating using a curtain flow coater or the like, comma coating, Mayer bar coating, or any other known method used for forming a cured layer. The curable elastomer composition of the present invention can also be applied in multiple layers. In this case, the curable elastomer composition may be applied multiple times in succession and then cured, or a new curable elastomer composition may be applied on top of a cured curable elastomer composition and then cured.

[0132] The release layer may also be called a release liner, separator, release layer, or release coating layer, and may suitably be a release layer having release coating capability such as a silicone-based release agent, a fluorine-based release agent, an alkyd-based release agent, or a fluorosilicone-based release agent, a release layer having physically formed fine irregularities on the substrate surface, or a release layer that is difficult to adhere to the cured layer of the present invention. In particular, in the film of the present invention, it is preferred to use a release layer obtained by curing a fluorosilicone-based release agent as the release layer.

[0133] [Manufacturing method using rolling processing] The method for producing the laminate of the present invention may further include a rolling step.

[0134] It is particularly preferred to obtain the film by applying the curable elastomer composition of the present invention to a substrate and then rolling the composition before or after the curing reaction. Although rolling can be performed on a cured or semi-cured product, it is preferred to roll an uncured curable elastomer composition and then cure it by heating or the like to obtain a flat and uniform film. When rolling is performed, it is particularly preferred to roll the entire laminate in which the uncured curable elastomer composition is applied between separators having a release layer (described below) and then cure it by heating or the like to obtain a flat and uniform film.

[0135] The amount of the curable elastomer composition applied to the substrate must be such that the average thickness of the film after curing is 1 to 200 μm, and the thickness must be such that rolling processing is possible.

[0136] The rolling process can be carried out by applying the curable elastomer composition to a substrate and using a known rolling method such as roll rolling. If necessary, the cured or semi-cured product may be formed into a sheet and then rolled. The average thickness of the rolled film must be in the range of 1 to 200 μm. Roll rolling has the advantage of being able to design a film of the desired thickness by adjusting the gap between the rolls. For example, by rolling while adjusting the gap between the rolls to a constant value so that the average thickness is in the range of 1 to 200 μm, a film with excellent flatness and minimal defects on the surface and inside the film can be obtained. More specifically, in the case of roll rolling, it is particularly preferable that the gap between the rolls is adjusted to a value 2.0 to 4.0 times the average thickness of the desired film. For example, to obtain a 50 μm film, it is particularly preferable that the thickness of the release layer be in the range of 100 to 200 μm. If the gap is wider than the upper limit, voids, particularly those caused by air bubbles, may not be sufficiently eliminated, which may increase defects on the surface and inside the film.

[0137] As described above, the rolling process is preferably carried out after the curable elastomer composition is coated on a substrate and is in an uncured state. Specifically, the raw material curable elastomer composition is coated on a sheet-like substrate preferably provided with a release layer, and the coated substrate is rolled by rolling or the like, and the flattened curable elastomer composition is then cured by heating or the like to obtain the film of the present invention.

[0138] The method for applying the curable elastomer composition to a substrate before rolling, the substrate, etc. are the same as those described above, and the fluoroalkyl group-containing cured product having the primer layer and the planarizing layer may be further subjected to rolling, such as roll rolling.

[0139] [Design method for curable elastomers] The present invention also relates to a cured product having the following formula:

number

[0140] In the above formula, E is a value measured using a rigid electrode, and is 50 V / μm to 200 V / μm, preferably 70 V / μm to 150 V / μm.

[0141] In the above formula, α is 0.4 to 0.9, and preferably 0.6 to 0.85. In this design method, the closer to smooth the surface roughness of the obtained cured film, the higher the value of α can be.

[0142] In the above formula, Y is 0.001 MPa to 10 MPa, preferably 0.001 MPa to 2 MPa, and more preferably 0.001 MPa to 1.5 MPa.

[0143] In the above formula, ε γ is 100 or less, preferably 50 or less, and more preferably in the range of 1 to 10.

[0144] The above E, α, Y, or ε γ When the viscosity falls within the above range, it is possible to design a curable elastomer composition that satisfies the mechanical and electrical properties required for an electroactive polymer material used in a transducer device.

[0145] [Transducer device design method] The present invention also relates to a method for designing a transducer device, comprising the step of using a cured product of a curable elastomer composition selected according to the above-described method for designing a curable elastomer composition. The curable elastomer composition of the present invention is particularly useful as a dielectric layer of a transducer, and a transducer can be formed by disposing electrode layers on both ends of the cured product of the curable elastomer composition. The curable elastomer composition of the present invention containing conductive inorganic particles can also be used as an electrode layer.

[0146] In the present invention, the term "transducer" refers to a component, machine, or device for converting one type of energy into another type of energy. Examples of such transducers include artificial muscles and actuators for converting electrical energy into mechanical energy, sensors and power generation elements for converting mechanical energy into electrical energy, speakers, microphones, and headphones for converting electrical energy into sound energy, fuel cells for converting chemical energy into electrical energy, and light-emitting diodes for converting electrical energy into light energy.

[0147] A transducer comprising a cured product of the curable elastomer composition of the present invention may have a film or sheet-like cured product, particularly multiple layers. A transducer comprising a film or sheet of multiple layers of a cured product of the curable elastomer composition can generate a large force, and by stacking multiple layers, a larger displacement can be obtained.

[0148] As electrodes for producing a transducer, in addition to the cured product of the curable elastomer composition of the present invention, metals and alloys such as gold, platinum, silver, palladium, copper, nickel, aluminum, titanium, zinc, zirconium, iron, cobalt, tin, lead, indium, chromium, molybdenum, and manganese, metal oxides such as indium tin oxide (ITO), antimony tin oxide (ATO), ruthenium oxide, titanium oxide, zinc oxide, and tin oxide, carbon materials such as carbon nanotubes, carbon nanohorns, carbon nanosheets, carbon fibers, and carbon black, and conductive resins such as poly(ethylene-3,4-dioxythiophene) (PEDOT), polyaniline, and polypyrrole can be used. The electrodes may contain one of the above materials alone or two or more of them.

[0149] A transducer comprising a cured product of the curable elastomer composition of the present invention can operate in air, water, a vacuum, or an organic solvent. Additionally, the transducer can be appropriately sealed depending on the environment in which it is used. There are no particular limitations on the sealing method, and it can be sealed using, for example, a resin material.

[0150] A film of the cured product of a curable elastomer composition selected according to the method for designing a curable elastomer composition of the present invention is less likely to undergo dielectric breakdown when a high voltage is applied and electricity is passed through it, and the film as a whole can achieve high electrical properties such as high dielectric breakdown strength, as well as high mechanical properties such as tear strength, tensile strength, and elongation, and can satisfy all of the performance requirements for a transducer device. Therefore, a curable film of a curable elastomer composition selected according to the method for designing a curable elastomer composition of the present invention, in the form of a single-layer or laminate film, is particularly suitable as a component for a transducer device for designing actuators that are activated under high voltage and convert electrical signals into physical movement. [Example]

[0151] The present invention will be described below with reference to examples, but the present invention is not limited to these examples. The following compounds were used in the examples.

[0152] Component (a1-1): Dimethylsiloxane polymer with both ends blocked with vinyldimethylsiloxy groups (vinyl group content: 0.24% by mass, siloxane polymerization degree: 300) Component (a1-2): Both ends blocked with vinyldimethylsiloxy groups, 3,3,3-trifluoropropylmethyl, dimethylsiloxane copolymer (vinyl group content: 0.26% by mass, siloxane polymerization degree: 193) Component (b1): Both ends blocked with trimethylsiloxy groups, dimethylsiloxy-methylhydrosiloxy-siloxane copolymer (silicon-bonded water content: 0.71% by mass) Component (b2): Dimethylsiloxane polymer with both ends blocked by dimethylhydrosiloxy groups (silicon-bonded water content: 0.02% by mass) Component (b3): ​​Trimethylsiloxy-terminated dimethylsiloxane-3,3,3-trifluoropropylmethylsiloxane-methylhydrogensiloxane copolymer (silicon-bonded hydrogen content (wt%): approximately 0.23) Component (b4): Dimethylsiloxane-3,3,3-trifluoropropylmethylsiloxane copolymer, both ends blocked with dimethylhydrosiloxy groups (silicon-bonded hydrogen content (wt%): approximately 0.014) Component (c1): A solution of platinum-1,3-divinyl 1,1,3,3-tetramethyldisiloxane complex in a dimethylsiloxane polymer capped at both ends with vinyldimethylsiloxy groups (platinum concentration: approximately 0.6% by weight) Ingredient (e1): 1-ethynyl-1-cyclohexanol Ingredient (e2): 1,3,5,7-tetramethyl-1,3,5,7-tetravinyl-cyclotetrasiloxane Component (f1): Fumed silica treated with hexamethyldisilazane (product name before treatment: Aerosil 200) Component (f2): Fumed silica treated with hexamethyldisilazane (product name before treatment: Aerosil 50) Component (f3): Fumed silica treated with hexamethyldisilazane and 1,3-bis(3,3,3-trifluoropropyl)-1,1,3,3-tetramethyldisilazane (product name before treatment: Aerosil 200) Component (f4): Fumed silica treated with hexamethyldisilazane and 1,3-bis(3,3,3-trifluoropropyl)-1,1,3,3-tetramethyldisilazane (product name before treatment: Aerosil 50)

[0153] [Viscosity before curing] The viscosity of each composition before curing was measured using a viscoelasticity measuring device (Anton Paar, model MCR102). Measurements were carried out using a cone-plate with a diameter of 20 mm and an angle of 2°, with varying shear rates. -1 ) and 10.0(S -1 The overall viscosity of each composition measured at 100°C was recorded.

[0154] [Mechanical property measurement of cured product] Each composition was press-cured at 110°C for 15 minutes and then post-cured in an oven at 110°C for 45 minutes to obtain a cured product. The tear strength, tensile strength, elongation at break, and Young's modulus of the resulting cured product were measured according to JIS-K6249. For mechanical strength measurements, the sheet thickness was 2 mm. Durometer A hardness of a 6 mm thick sheet was also measured.

[0155] [Measurement of the relative dielectric constant of the cured product] Similarly, 1 mm thick sheets were prepared, and the dielectric constants were measured at room temperature in the frequency range of 100 Hz to 1 MHz using an impedance analyzer 4990EDMS-050 (manufactured by Toyo Corporation). The dielectric constants of the cured product sheets in Examples 1 and 2 at 100 kHz were 3 and 5, respectively.

[0156] [Measurement of dielectric breakdown strength of cured product] Each composition was coated using a coater and cured at 110°C for 60 minutes to produce a sheet with a thickness of 0.01 mm. The resulting sheet was used to measure the dielectric breakdown strength using an electrical insulating oil breakdown voltage tester equipped with rigid electrodes, a PORTATEST 100A-2 manufactured by Soken Denki Co., Ltd. Measurements were taken at 16 locations within an area of ​​10 cm x 10 cm for each cured sheet sample, and the average value was taken as the dielectric breakdown strength.

[0157] Example 1 Liquid curable organopolysiloxane composition 1 was prepared by blending the above component (a1-1) at 70.58 wt%, component (f1) at 22.10 wt%, component (f2) at 4.35 wt%, component (b1) at 0.99 wt%, component (b2) at 3.83 wt%, component (c1) at 0.10 wt%, and component (e1) at 0.04 wt%. Components (b1) and (b2) were used in amounts such that the silicon-bonded hydrogen atoms (Si-H) of the composition were approximately 1.2 moles per mole of vinyl groups. The viscosity before curing was 0.1 (S -1 ) at 218 Pa·s and 10.0 (S -1 ) was 26 Pa·s.

[0158] Example 2 A liquid curable organopolysiloxane composition was prepared by blending the above components (a1-2) at 68.36 wt%, (b3) at 5.06 wt%, (b4) at 5.06 wt%, (c1) at 0.10 wt%, (f3) at 18.88 wt%, (f4) at 2.34 wt%, and (e2) at 0.28 wt%. Components (b3) and (b4) were used in amounts such that the silicon-bonded hydrogen atoms (Si-H) of the components (b3) and (b4) were approximately 1.2 moles per mole of vinyl groups in the composition. The viscosity before curing was 0.1 (S -1 ) at 148 Pa·s and 10.0 (S -1 ) was 16 Pa·s.

[0159] [Table 1] [Industrial Applicability]

[0160] The uses of the cured film of the curable elastomer composition of the present invention are not limited to those disclosed above, and can be used in a variety of flat panel displays (FPDs) for displaying characters, symbols, and images, such as television sets, computer monitors, monitors for personal digital assistants, surveillance monitors, video cameras, digital cameras, mobile phones, personal digital assistants, dashboard displays for automobiles, dashboard displays for various facilities, devices, and equipment, ticket vending machines, and automated teller machines. Examples of applicable devices include CRT displays, liquid crystal displays, plasma displays, organic electroluminescent displays, inorganic electroluminescent displays, LED displays, surface electrolytic displays (SEDs), and field emission displays (FEDs), as well as touch panels utilizing these displays. Similarly, the film of the present invention is a film- or sheet-like member with excellent electrical and mechanical properties, including dielectric breakdown strength, and has a high dielectric constant and mechanical strength (specifically, tensile strength, tear strength, elongation, etc.). Therefore, the film of the present invention can be used as an electronic material, a member for a display device, or a member for a transducer (including those for sensors, speakers, actuators, and generators), and is particularly suitable for use as an electroactive film (dielectric layer or electrode layer) constituting a transducer. Specific methods for using the film include known methods for using a dielectric layer or a pressure-sensitive adhesive layer, without any particular restrictions.

[0161] Furthermore, by using the method for designing a curable elastomer composition of the present invention, it is possible to easily design or select a film- or sheet-like member that has excellent electrical and mechanical properties, including dielectric breakdown strength, and a cured film that has a high dielectric constant and mechanical strength (specifically, tensile strength, tear strength, elongation, etc.). Furthermore, by selecting or designing a curable elastomer composition that gives a cured product satisfying these parameters and using the film- or sheet-like member, it is possible to easily design a transducer device that has the required performance and is highly practical.

Claims

1. The highly dielectric functional group contains a compound having a 3,3,3-trifluoropropyl group, and the cured product has the following formula: [Equation 1] (where E is the dielectric breakdown strength measured using rigid electrodes in the range of 50 V / μm to 200 V / μm, α is a number in the range of 0.7 to 0.9, Y is the Young's modulus in the range of 0.001 MPa to 10 MPa, and ε γ is the relative permittivity of 100 or less, and ε ０ represents the dielectric constant of a vacuum) Fulfilling (a1) a linear or branched organopolysiloxane having alkenyl groups only at the molecular chain terminals; (b3): ​​dimethylsiloxane / 3,3,3-trifluoropropylmethylsiloxane / methylhydrogensiloxane copolymer, both ends blocked with trimethylsiloxy groups; (b4): Dimethylsiloxane-3,3,3-trifluoropropylmethylsiloxane copolymer, both ends of which are blocked with dimethylhydrosiloxy groups, and (C) Hydrosilylation reaction catalyst 1. A curable elastomeric composition comprising:

2. The curable elastomeric composition of claim 1 for use in a transducer device.

3. A cured product of the curable elastomer composition of claim 1.

4. An electronic component comprising the cured product according to claim 3 .

5. A film comprising the cured product according to claim 3.

6. A laminate comprising the film of claim 5 and a release layer.

7. A step of applying the curable elastomer composition according to claim 1 in the form of a thin film on a separator having a release layer so that the thickness after curing is in the range of 1 to 1000 μm; a step of curing the curable elastomer composition applied in the form of a thin film; A method for producing a laminate, comprising:

8. The method for producing a laminate according to claim 7 , further comprising a rolling process step.

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