JP2018172627A - Insulating paste - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an insulating paste from which an insulating resin film excellent in mechanical strength and durability is obtained.SOLUTION: An insulating paste contains an elastomer composition containing silica particles, and a solvent. The elastomer composition contains a thermosetting elastomer composition for forming one or more elastomers selected from the group consisting of a silicone rubber, a urethane rubber and a fluorine rubber. The insulating paste is used for forming a substrate 20 constituting an elastic wiring board 50.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an insulating paste.

  In recent years, various developments have been made on materials used for substrates constituting stretchable wiring boards. As this type of technology, for example, the technology described in Patent Document 1 is known. According to the same literature, as a method for producing the elastomer base material 11, a kneaded product obtained by kneading a silicone rubber polymer, a processing aid and a crosslinking agent was heated at 150 ° C. for 5 minutes by far infrared rays to obtain a silicone rubber. (Patent Document 1, paragraph 0037).

Japanese Patent Laying-Open No. 2015-55615

  However, as a result of examination by the present inventors, it has been found that the kneaded material used for the silicone rubber described in the above-mentioned literature has room for improvement in terms of mechanical strength and durability.

  The inventor further examined that by adding silica particles to the insulating paste containing the elastomer composition and the solvent, in the insulating resin film such as a substrate using such an insulating paste, As a result, it was found that the mechanical strength and durability can be improved, and the present invention has been completed.

According to the present invention,
An elastomer composition containing silica particles (C);
Insulating paste comprising a solvent is provided.

  According to the present invention, an insulating paste excellent in mechanical strength and durability can be provided.

It is sectional drawing which shows the outline of the electronic device in this embodiment. It is sectional drawing which shows the outline of the manufacturing process of the electronic device in this embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same reference numerals are given to the same components, and the description will be omitted as appropriate. In the present specification, “to” represents the following from the above unless otherwise specified.

The outline | summary of the insulating paste of this embodiment is demonstrated.
The insulating paste of the present embodiment can include an elastomer composition containing silica particles (C) and a solvent.

  Since the insulating paste of this embodiment is comprised with the paste-like insulating resin composition containing a solvent, it is excellent in the applicability | paintability and film-forming property on a support base material. Since this insulating paste contains silica particles (C), it is possible to increase the mechanical strength and durability of an elastomer composed of a cured product of the insulating paste. By applying the elastomer made of the insulating paste to the insulating resin film constituting the stretchable wiring substrate, the mechanical strength and durability of the insulating resin film can be improved. Thereby, the insulating paste of this embodiment can be suitable for the use which forms the board | substrate which comprises a stretchable wiring board, for example.

  Hereinafter, each component of the insulating paste of this embodiment will be described.

  The insulating paste of this embodiment can contain an elastomer composition. Accordingly, even when an elastomer made of an insulating paste is used for a stretchable substrate or the like, moderate stretchability can be expressed with respect to the elastomer. Moreover, the insulating paste of this embodiment can contain a silica particle (C). Thereby, the mechanical strength of the elastomer made of an insulating paste can be improved.

  The elastomer composition is used to form an elastomer. For example, the elastomer composition is used to form one or more thermosetting elastomers selected from the group consisting of silicone rubber, urethane rubber, and fluororubber. A composition can be included, and preferably a silicone rubber-based curable composition can be included.

As the elastomer, silicone rubber, urethane rubber, fluorine rubber, nitrile rubber, acrylic rubber, styrene rubber, chloroprene rubber, ethylene propylene rubber, or the like can be used. Among these, the elastomer can include one or more thermosetting elastomers selected from the group consisting of silicone rubber, urethane rubber, and fluororubber. The elastomer can contain silicone rubber from the viewpoint of being chemically stable and excellent in mechanical strength.
The said thermosetting elastomer can be comprised with the hardened | cured material of a thermosetting elastomer composition. For example, the silicone rubber can be composed of a cured product of a silicone rubber-based curable composition. The thermoplastic elastomer can be composed of a dried product of the thermoplastic elastomer. In the present specification, the elastomer of the insulating paste means an elastomer formed by drying or curing the insulating paste.

  Hereinafter, a case where a silicone rubber-based curable composition is used as the silicone rubber which is an example of the elastomer of the present embodiment will be described.

  The silicone rubber-based curable composition of the present embodiment can contain a vinyl group-containing organopolysiloxane (A). The vinyl group-containing organopolysiloxane (A) is a polymer that is a main component of the silicone rubber-based curable composition of the present embodiment.

  The vinyl group-containing organopolysiloxane (A) can include a vinyl group-containing linear organopolysiloxane (A1) having a linear structure.

  The vinyl group-containing linear organopolysiloxane (A1) has a linear structure and contains a vinyl group, and this vinyl group serves as a crosslinking point during curing.

  The vinyl group content of the vinyl group-containing linear organopolysiloxane (A1) is not particularly limited. For example, the vinyl group-containing linear organopolysiloxane preferably has 2 or more vinyl groups in the molecule and 15 mol% or less. More preferably, it is 0.01-12 mol%. Thereby, the quantity of the vinyl group in vinyl group containing linear organopolysiloxane (A1) is optimized, and formation of the network with each component mentioned later can be performed reliably. In this embodiment, “to” means to include numerical values at both ends thereof.

  In addition, in this specification, vinyl group content is the mol% of a vinyl group containing siloxane unit when all the units which comprise a vinyl group containing linear organopolysiloxane (A1) are 100 mol%. . However, one vinyl group is considered for one vinyl group-containing siloxane unit.

  The degree of polymerization of the vinyl group-containing linear organopolysiloxane (A1) is not particularly limited, but for example, it is preferably in the range of about 1000 to 10000, more preferably about 2000 to 5000. In addition, a polymerization degree can be calculated | required as a number average polymerization degree (or number average molecular weight) of polystyrene conversion in GPC (gel permeation chromatography) which used chloroform as a developing solvent, for example.

  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.

  By using a vinyl group-containing linear organopolysiloxane (A1) having a polymerization degree and specific gravity within the above ranges, the resulting silicone rubber has heat resistance, flame retardancy, chemical stability, etc. Can be improved.

  The vinyl group-containing linear organopolysiloxane (A1) is particularly preferably one having a structure represented by the following formula (1).

In formula (1), R ¹ is a substituted or unsubstituted alkyl group, alkenyl group, aryl group having 1 to 10 carbon atoms, or a hydrocarbon group obtained by combining these. As a C1-C10 alkyl group, a methyl group, an ethyl group, a propyl group etc. are mentioned, for example, Among these, a methyl group is preferable. As a C1-C10 alkenyl group, a vinyl group, an allyl group, a butenyl group etc. are mentioned, for example, Among these, a vinyl group is preferable. Examples of the aryl group having 1 to 10 carbon atoms include a phenyl group.

R ² is a substituted or unsubstituted alkyl group, alkenyl group, aryl group having 1 to 10 carbon atoms, or a hydrocarbon group obtained by combining these. As a C1-C10 alkyl group, a methyl group, an ethyl group, a propyl group etc. are mentioned, for example, 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.

R ³ is a substituted or unsubstituted alkyl group having 1 to 8 carbon atoms, an aryl group, or a hydrocarbon group obtained by combining these. As a C1-C8 alkyl group, a methyl group, an ethyl group, a propyl group etc. are mentioned, for example, Among these, a methyl group is preferable. Examples of the aryl group having 1 to 8 carbon atoms include a phenyl group.

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

In the formula (1), a plurality of R ¹ are independent from each other and may be different from each other or the same. The same applies to R ² and R ³ .

  Further, m and n are the number of repeating units constituting the vinyl group-containing linear organopolysiloxane (A1) represented by the formula (1), m is an integer of 0 to 2000, and n is 1000 to 10,000. Is an integer. m is preferably 0 to 1000, and n is preferably 2000 to 5000.

  Moreover, as a specific structure of a vinyl group containing linear organopolysiloxane (A1) represented by Formula (1), what is represented, for example by following formula (1-1) is mentioned.

In Formula (1-1), R ¹ and R ² are each independently a methyl group or a vinyl group, and at least one is a vinyl group.

  Furthermore, the vinyl group-containing linear organopolysiloxane (A1) contains a first vinyl group having a vinyl group content of 2 or more vinyl groups in the molecule and not more than 0.4 mol%. It contains a 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%. Preferably there is. As raw rubber, which is a raw material of silicone rubber, a first vinyl group-containing linear organopolysiloxane (A1-1) having a general vinyl group content and a second vinyl group-containing direct polymer having a high vinyl group content By combining with the chain organopolysiloxane (A1-2), the vinyl groups can be unevenly distributed, and the crosslink 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 increased more effectively.

Specifically, as the vinyl group-containing linear organopolysiloxane (A1), for example, in the above formula (1-1), a unit in which R ¹ is a vinyl group and / or a unit in which R ² is a vinyl group A first vinyl group-containing linear organopolysiloxane (A1-1) having two or more in the molecule and containing 0.4 mol% or less, a unit in which R ¹ is a vinyl group, and / or R ^It is preferable to use a second vinyl group-containing linear organopolysiloxane (A1-2) containing 0.5 to 15 mol% of a unit in which ² is a vinyl group.

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

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

  Each of the first and second vinyl group-containing linear organopolysiloxanes (A1-1) and (A1-2) may be used alone or in combination of two or more. Good.

  The vinyl group-containing organopolysiloxane (A) may include a vinyl group-containing branched organopolysiloxane (A2) having a branched structure.

<< organohydrogenpolysiloxane (B) >>
The silicone rubber-based curable composition of the present 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. Either or both can be included.

  The straight-chain organohydrogenpolysiloxane (B1) has a straight-chain structure and a structure in which hydrogen is directly bonded to Si (≡Si—H), and is a vinyl group-containing organopolysiloxane (A). In addition to the vinyl group, the polymer is a polymer that undergoes a hydrosilylation reaction with a vinyl group contained in a component blended in the silicone rubber-based curable composition to crosslink these components.

  The molecular weight of the linear organohydrogenpolysiloxane (B1) is not particularly limited. For example, the weight average molecular weight is preferably 20000 or less, and more preferably 1000 or more and 10,000 or less.

  In addition, the weight average molecular weight of linear organohydrogenpolysiloxane (B1) can be measured by polystyrene conversion in GPC (gel permeation chromatography) which used chloroform as a developing solvent, for example.

  Moreover, it is preferable that the linear organohydrogenpolysiloxane (B1) usually has no vinyl group. Thereby, it can prevent exactly that a crosslinking reaction advances in the molecule | numerator of linear organohydrogenpolysiloxane (B1).

  As the linear organohydrogenpolysiloxane (B1) as described above, for example, those having a structure represented by the following formula (2) are preferably used.

In formula (2), R ⁴ represents a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, an alkenyl group, an aryl group, a hydrocarbon group combining these, or a hydride group. As a C1-C10 alkyl group, a methyl group, an ethyl group, a propyl group etc. are mentioned, for example, Among these, a methyl group is preferable. As a C1-C10 alkenyl group, a vinyl group, an allyl group, a butenyl group etc. are mentioned, for example. Examples of the aryl group having 1 to 10 carbon atoms include a phenyl group.

R ⁵ is a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, an alkenyl group, an aryl group, a hydrocarbon group combining these, or a hydride group. Examples of the alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group, and a propyl group, and among them, a methyl group is preferable. As a C1-C10 alkenyl group, a vinyl group, an allyl group, a butenyl group etc. are mentioned, for example. Examples of the aryl group having 1 to 10 carbon atoms include a phenyl group.

In the formula (2), the plurality of R ⁴ are independent from each other and may be different from each other or the same. The same is true for R ^5. However, at least two of the plurality of R ⁴ and R ⁵ are hydride groups.

R ⁶ is a substituted or unsubstituted alkyl group having 1 to 8 carbon atoms, an aryl group, or a hydrocarbon group obtained by combining these. As a C1-C8 alkyl group, a methyl group, an ethyl group, a propyl group etc. are mentioned, for example, Among these, a methyl group is preferable. Examples of the aryl group having 1 to 8 carbon atoms include a phenyl group. The plurality of R ⁶ are independent from each other and may be different from each other or the same.

In addition, as a substituent of R < ⁴ >, R < ⁵ >, R < ⁶ > in Formula (2), a methyl group, a vinyl group etc. are mentioned, for example, and a methyl group is preferable from a viewpoint of preventing the crosslinking reaction in a molecule | numerator.

  Further, m and n are the number of repeating units constituting the linear organohydrogenpolysiloxane (B1) represented by the formula (2), m is an integer of 2 to 150, and n is an integer of 2 to 150. It is. Preferably, m is an integer of 2 to 100, and n is an integer of 2 to 100.

  In addition, linear organohydrogenpolysiloxane (B1) may be used individually by 1 type, and may be used in combination of 2 or more type.

  Since the branched organohydrogenpolysiloxane (B2) has a branched structure, it forms a region having a high crosslinking density and is a component that greatly contributes to the formation of a dense structure having a crosslinking density in the system of silicone rubber. Further, similar to the above-mentioned linear organohydrogenpolysiloxane (B1), it has a structure in which hydrogen is directly bonded to Si (≡Si—H), and in addition to the vinyl group of the vinyl group-containing organopolysiloxane (A), silicone It is a polymer that undergoes a hydrosilylation reaction with the vinyl group of the components blended in the rubber-based curable composition to crosslink these components.

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

  Furthermore, it is preferable that the branched organohydrogenpolysiloxane (B2) usually has no vinyl group. Thereby, it can prevent exactly that a crosslinking reaction advances in the molecule | numerator of branched organohydrogenpolysiloxane (B2).

  Further, as the branched organohydrogenpolysiloxane (B2), those represented by the following average composition formula (c) are preferable.

Average composition formula (c)
(H _a (R ⁷ ) _3-a SiO _1/2 ) _m (SiO _4/2 ) _n
(In the formula (c), R ⁷ is a monovalent organic group, a is an integer in the range of 1 to 3, m is the number of H _a (R ⁷ ) _3-a SiO _1/2 units, and n is SiO _{4 / 2} units)

In the 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 obtained by combining these. As a C1-C10 alkyl group, a methyl group, an ethyl group, a propyl group etc. are mentioned, for example, Among these, a methyl group is preferable. Examples of the aryl group having 1 to 10 carbon atoms include a phenyl group.

  In the formula (c), a is the number of hydride groups (hydrogen atoms directly bonded to Si), and is an integer in the range of 1 to 3, preferably 1.

In the formula (c), m is the number of H _a (R ⁷ ) _3-a SiO _1/2 units, and n is the number of SiO _4/2 units.

  The branched organohydrogenpolysiloxane (B2) has a branched structure. The linear organohydrogenpolysiloxane (B1) differs from the branched organohydrogenpolysiloxane (B2) in that the structure is linear or branched. The number of alkyl groups R to be bonded (R / Si) is 1.8 to 2.1 for linear organohydrogenpolysiloxane (B1), and 0.8 to 1 for branched organohydrogenpolysiloxane (B2). .7 range.

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

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

In Formula (3), R ⁷ is a substituted or unsubstituted alkyl group having 1 to 8 carbon atoms, an aryl group, a hydrocarbon group obtained by combining these, or a hydrogen atom. As a C1-C8 alkyl group, a methyl group, an ethyl group, a propyl group etc. are mentioned, for example, Among these, a methyl group is preferable. Examples of the aryl group having 1 to 8 carbon atoms include a phenyl group. Examples of the substituent for R ⁷ include a methyl group.

In formula (3), a plurality of R ⁷ are independent from each other and may be different from each other or the same.

  In Formula (3), “—O—Si≡” represents that Si has a branched structure spreading in three dimensions.

  In addition, a branched organohydrogenpolysiloxane (B2) may be used individually by 1 type, and may be used in combination of 2 or more type.

  In the linear organohydrogenpolysiloxane (B1) and the branched organohydrogenpolysiloxane (B2), the amount of hydrogen atoms (hydride groups) directly bonded to Si is not particularly limited. However, in the silicone rubber-based curable composition, the linear organohydrogenpolysiloxane (B1) and the branched organohydrogenpolypolyol with respect to 1 mol of the vinyl group in the vinyl group-containing linear organopolysiloxane (A1). The amount of the total amount of hydride groups of siloxane (B2) is preferably 0.5 to 5 mol, and more preferably 1 to 3.5 mol. This ensures the formation of a crosslinked network between the linear organohydrogenpolysiloxane (B1) and the branched organohydrogenpolysiloxane (B2) and the vinyl group-containing linear organopolysiloxane (A1). Can be made.

In this embodiment, the content of the elastomer composition in the insulating paste is preferably 5% by mass or more, more preferably 8% by mass or more, and more preferably 10% by mass with respect to the entire insulating paste. More preferably, it is the above. In addition, the content of the elastomer composition in the insulating paste is preferably 50% by mass or less, more preferably 45% by mass or less, and 40% by mass or less with respect to the entire insulating paste. More preferably.
By setting the content of the elastomer composition to the lower limit value or more, the elastomer made of the insulating paste can have an appropriate flexibility. Moreover, the mechanical strength of an elastomer can be improved by making content of an elastomer composition below the said upper limit.

<< Silica particles (C) >>
The insulating paste of this embodiment can contain a silica particle (C) as needed. Thereby, the improvement of the hardness and mechanical strength of the elastomer formed from an insulating paste can be aimed at. Moreover, the insulating property of the elastomer of the insulating paste can be enhanced.

  Although it does not specifically limit as a silica particle (C), For example, fumed silica, baked silica, precipitated silica, etc. are used. These may be used alone or in combination of two or more.

Silica particles (C) are, for example, it is preferable that the specific surface area by the BET method, for example, 50 to 400 m ² / g, and more preferably 100 to 400 m ² / g. Further, the average primary particle diameter of the silica particles (C) is preferably, for example, 1 to 100 nm, and more preferably about 5 to 20 nm.

  By using the silica particles (C) within the range of the specific surface area and the average particle diameter, it is possible to improve the hardness and mechanical strength of the formed silicone rubber, particularly the tensile strength.

In the present embodiment, the content of the silica particles (C) in the insulating paste is preferably 1% by mass or more, more preferably 3% by mass or more, with respect to the entire insulating paste. More preferably, it is at least mass%. The content of the silica particles (C) in the insulating paste is preferably 50% by mass or less, more preferably 45% by mass or less, and more preferably 40% by mass or less with respect to the entire insulating paste. More preferably.
By setting the content of the silica particles (C) to the above lower limit value or more, the elastomer of the insulating paste can have an appropriate mechanical strength. On the other hand, when the content of the silica particles (C) is set to the upper limit value or less, the elastomer can have appropriate stretch properties. Thereby, durability at the time of repeated use can be improved.

<< Silane coupling agent (D) >>
The silicone rubber-based curable composition of the present embodiment can contain a silane coupling agent (D).
The silane coupling agent (D) can have a hydrolyzable group. The surface modification of the silica particles (C) can be carried out by hydrolyzing the hydrolyzable groups with water to form hydroxyl groups, which undergo a dehydration condensation reaction with the hydroxyl groups on the surface of the silica particles (C).

  Moreover, this silane coupling agent (D) can contain the silane coupling agent which has a hydrophobic group. Thereby, since this hydrophobic group is imparted to the surface of the silica particles (C), the cohesive force of the silica particles (C) is reduced in the silicone rubber-based curable composition and thus in the silicone rubber (hydrogen due to silanol groups). As a result, the dispersibility of the silica particles in the silicone rubber-based curable composition is estimated to be improved. Thereby, the interface of a silica particle and a rubber matrix increases, and the reinforcement effect of a silica particle increases. Furthermore, when the rubber matrix is deformed, it is presumed that the sliding property of the silica particles in the matrix is improved. And the mechanical strength (for example, tensile strength, tear strength, etc.) of the silicone rubber by a silica particle (C) improves by the improvement of the dispersibility of silica particle (C), and the improvement of slipperiness.

  Furthermore, the silane coupling agent (D) can contain a silane coupling agent having a vinyl group. Thereby, a vinyl group is introduce | transduced into the surface of a silica particle (C). Therefore, when the silicone rubber-based curable composition is cured, that is, the vinyl group of the vinyl group-containing organopolysiloxane (A) and the hydride group of the organohydrogenpolysiloxane (B) undergo a hydrosilylation reaction. When the network (crosslinked structure) is formed, the vinyl group of the silica particles (C) is also involved in the hydrosilylation reaction with the hydride group of the organohydrogenpolysiloxane (B). Silica particles (C) are also taken in. Thereby, low hardness and high modulus of the formed silicone rubber can be achieved.

  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.

  As a silane coupling agent (D), what is represented by following formula (4) is mentioned, for example.

_{Y n -Si- (X) 4-} n ··· (4)
In said formula (4), n represents the integer of 1-3. Y represents a functional group of any one having a hydrophobic group, a hydrophilic group or a vinyl group. 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. It is a hydrophobic group. X represents a hydrolyzable group.

  The hydrophobic group is an alkyl group having 1 to 6 carbon atoms, an aryl group, or a hydrocarbon group that is a combination thereof, and examples thereof include a methyl group, an ethyl group, a propyl group, and a phenyl group. A methyl group is preferred.

  Examples of the hydrophilic group include a hydroxyl group, a sulfonic acid group, a carboxyl group, and a carbonyl group. Among these, a hydroxyl group is particularly preferable. The hydrophilic group may be included as a functional group, but is preferably not included from the viewpoint of imparting hydrophobicity to the silane coupling agent (D).

Furthermore, examples of the hydrolyzable group include an alkoxy group such as a methoxy group and an ethoxy group, a chloro group, and a silazane group. Among them, a silazane group is preferable because of its high reactivity with the silica particles (C). Incidentally, those having a silazane group as hydrolyzable groups, the characteristics of its structure the formula (4) in the structure of (Y _n -Si-) comes to have two.

  Specific examples of the silane coupling agent (D) represented by the above formula (4) include, for example, methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, methyltrimethoxysilane, having a hydrophobic group as a functional group. Alkoxysilanes such as ethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, decyltrimethoxysilane; methyltrichlorosilane Chlorosilanes such as dimethyldichlorosilane, trimethylchlorosilane, and phenyltrichlorosilane; hexamethyldisilazane, and methacryloxypropyltriethoxysilane having a vinyl group as a functional group. , Alkoxysilanes such as methacryloxypropyltrimethoxysilane, methacryloxypropylmethyldiethoxysilane, methacryloxypropylmethyldimethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, vinylmethyldimethoxysilane; vinyltrichlorosilane, vinylmethyl Chlorosilanes such as dichlorosilane; divinyltetramethyldisilazane can be mentioned. Among them, considering the above description, hexamethyldisilazane having a hydrophobic group and divinyltetramethyl having a vinyl group are particularly preferable. Disilazane is preferred.

In this embodiment, the lower limit of the content of the silane coupling agent (D) is preferably 1% by mass or more with respect to 100 parts by weight of the total amount of the vinyl group-containing organopolysiloxane (A). The content is more preferably at least 5% by mass, and even more preferably at least 5% by mass. Moreover, it is preferable that the upper limit of content of a silane coupling agent (D) is 100 mass% or less with respect to 100 weight part of total amounts of vinyl group containing organopolysiloxane (A), and 80 mass% or less. It is more preferable that it is 40 mass% or less.
By setting the content of the silane coupling agent (D) to the above lower limit or more, the elastomer of the insulating paste has appropriate adhesion to the substrate, and when the silica particles (C) are used, the elastomer It can contribute to improvement of mechanical strength as a whole. Moreover, an elastomer can have an appropriate mechanical characteristic by making content of a silane coupling agent (D) below into the said upper limit.

<< Platinum or platinum compound (E) >>
The silicone rubber-based curable composition of the present embodiment can contain platinum or a platinum compound (E).
Platinum or a platinum compound (E) is a catalyst component that acts as a catalyst during curing. The amount of platinum or platinum compound (E) added is a catalytic amount.

  As the platinum or platinum compound (E), known ones can be used, for example, platinum black, platinum supported on silica or carbon black, chloroplatinic acid or an alcohol solution of chloroplatinic acid, chloride Examples thereof include complex salts of platinum acid and olefins, complex salts of chloroplatinic acid and vinyl siloxane, and the like.

  In addition, platinum or a platinum compound (E) may be used individually by 1 type, and may be used in combination of 2 or more type.

In the present embodiment, the content of platinum or the platinum compound (E) in the insulating paste is preferably 0.0001% by mass or more and 0.0002% by mass or more with respect to the entire insulating paste. More preferably, the content is 0.0003% by mass or more. Further, the content of platinum or platinum compound (E) in the insulating paste is preferably 1% by mass or less, more preferably 0.5% by mass or less, based on the entire insulating paste. More preferably, it is 0.1 mass% or less.
By setting the content of platinum or the platinum compound (E) to the above lower limit value or more, the insulating paste can be cured at an appropriate speed. Moreover, it can contribute to the reduction of the cost at the time of producing insulating paste by making content of platinum or a platinum compound (E) below the said upper limit.

<< Water (F) >>
Moreover, the silicone rubber-based curable composition of the present embodiment may contain water (F) in addition to the components (A) to (E).

  Water (F) is a component that functions as a dispersion medium for dispersing each component contained in the silicone rubber-based curable composition and contributes to the reaction between the silica particles (C) and the silane coupling agent (D). . Therefore, in the silicone rubber, the silica particles (C) and the silane coupling agent (D) can be more reliably connected to each other, and uniform characteristics can be exhibited as a whole.

  Furthermore, when it contains water (F), the content can be set as appropriate. Specifically, for example, 10 to 100 parts by weight with respect to 100 parts by weight of the silane coupling agent (D). Is preferable, and the range of 30 to 70 parts by weight is more preferable. Thereby, reaction with a silane coupling agent (D) and a silica particle (C) can be advanced more reliably.

(Other ingredients)
Furthermore, the silicone rubber-based curable composition of the present embodiment can further contain other components in addition to the components (A) to (F). Examples of other components include silica particles (C) other than diatomaceous earth, iron oxide, zinc oxide, titanium oxide, barium oxide, magnesium oxide, cerium oxide, calcium carbonate, magnesium carbonate, zinc carbonate, glass wool, mica, and the like. Inorganic fillers, reaction inhibitors, dispersants, pigments, dyes, antistatic agents, antioxidants, flame retardants, thermal conductivity improvers and the like.

(solvent)
The insulating paste of this embodiment contains a solvent. Various known solvents can be used as this solvent, and for example, a high boiling point solvent can be included. These may be used alone or in combination of two or more.

  The lower limit of the boiling point of the high-boiling solvent is, for example, 100 ° C. or higher, preferably 130 ° C. or higher, and more preferably 150 ° C. or higher. Thereby, when apply | coating an insulating paste on a support substrate, the film-forming property of the coating film obtained can be improved, and the film thickness variation of a coating film can be suppressed. On the other hand, the upper limit of the boiling point of the high-boiling solvent is not particularly limited, but may be, for example, 300 ° C. or less, 290 ° C. or less, or 280 ° C. or less. Thereby, since excessive thermal history at the time of wiring formation can be suppressed, damage to electronic components and wiring can be suppressed. In addition, since the substrate in which the solvent in the elastomer of the insulating paste is sufficiently volatilized can be used as the substrate, the shape of the wiring formed by printing using the conductive paste on the surface of the substrate can be favorably maintained. .

  Further, the solvent of the present embodiment can be appropriately selected from the viewpoint of the solubility and boiling point of the elastomer. For example, it is an aliphatic hydrocarbon having 5 to 20 carbon atoms, preferably an aliphatic hydrocarbon having 8 to 18 carbon atoms. A hydrocarbon, more preferably an aliphatic hydrocarbon having 10 to 15 carbon atoms can be contained.

Examples of the solvent of this embodiment include aliphatic hydrocarbons such as pentane, hexane, cyclohexane, heptane, methylcyclohexane, ethylcyclohexane, octane, decane, dodecane, and tetradecane; benzene, toluene, ethylbenzene, and xylene , Aromatic hydrocarbons such as mesitylene, trifluoromethylbenzene, 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, diethylene glycol mono Butyl ether, dipropylene glycol dimethyl ether, dipropylene glycol methyl Ethers such as n-propyl ether, 1,4-dioxane, 1,3-dioxane, tetrahydrofuran; dichloromethane, chloroform, 1,1-dichloroethane, 1,2-dichloroethane, 1,1,1-trichloroethane, 1, Haloalkanes such as 1,2-trichloroethane; carboxylic acid amides such as N, N-dimethylformamide and N, N-dimethylacetamide; sulfoxides such as dimethyl sulfoxide and diethyl sulfoxide; esters such as diethyl carbonate be able to. These may be used alone or in combination of two or more.
The solvent used here may be appropriately selected from solvents that can uniformly dissolve or disperse the composition components in the insulating paste.

In the solvent, the upper limit value of the polar term (δ _p ) of the Hansen solubility parameter is, for example, 10 MPa ^1/2 or less, preferably 7 MPa ^1/2 or less, more preferably 5.5 MPa ^1/2 or less. A first solvent may be included. Thereby, the dispersibility and solubility of the elastomer composition such as the silicone rubber-based curable resin composition in the insulating paste can be improved. The lower limit value of the polar term (δ _p ) of the first solvent is not particularly limited, but may be 0 Pa ^1/2 or more, for example.

The upper limit value of the hydrogen bond term (δ _h ) of the Hansen solubility parameter in the first solvent is, for example, 20 MPa ^1/2 or less, preferably 10 MPa ^1/2 or less, more preferably 7 MPa ^1/2 or less. is there. Thereby, in the insulating paste, the dispersibility and solubility of the elastomer composition such as the silicone rubber-based curable resin composition can be improved. The lower limit value of the hydrogen bond term (δ _h ) of the first solvent is not particularly limited, but may be, for example, 0 Pa ^1/2 or more.

Hansen's solubility parameter (HSP) is an index representing the solubility of how much a certain substance dissolves in another certain substance. HSP represents solubility as a three-dimensional vector. This three-dimensional vector can be typically represented by a dispersion term (δ _d ), a polarity term (δ _p ), and a hydrogen bond term (δ _h ). Those having similar vectors can be judged to have high solubility. It is possible to determine the similarity of vectors by the distance (HSP distance) of the Hansen solubility parameter.

The Hansen solubility parameter (HSP value) used in the present specification can be calculated using software called HSPiP (Hansen Solubility Parameters in Practice). Here, the computer software HSPiP developed by Hansen and Abbott includes a database describing the function of calculating the HSP distance and the Hansen parameters of various resins and solvents or non-solvents.
The solubility of each resin in a pure solvent and a mixed solvent of a good solvent and a poor solvent is investigated, and the result is input to the HSPiP software. D: Dispersion term, P: Polar term, H: Hydrogen bond term, R0: Dissolving sphere radius Is calculated.

  As the solvent of the present embodiment, for example, a solvent having a small difference in HSP distance, polarity term or hydrogen bond term between the constituent unit constituting the elastomer or the elastomer and the solvent can be selected.

  The lower limit of the viscosity of the insulating paste when measured at a shear rate of 20 [1 / s] at a room temperature of 25 ° C. is, for example, 1 Pa · s or more, preferably 5 Pa · s or more, more preferably 10 Pa · s. s or more. Thereby, the film formability can be improved. In addition, variation in film thickness can be suppressed even when a thick film is formed. On the other hand, the upper limit of the viscosity of the 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. Thereby, the application ease of an insulating paste can be improved.

  In the insulating paste in the present embodiment, the viscosity when measured at a shear rate of 1 [1 / s] at a room temperature of 25 ° C. is η1, the viscosity when measured at a shear rate of 5 [1 / s] is η5, Let the thixo index be the viscosity ratio (η1 / η5). At this time, the lower limit value of the thixo index is, for example, 1.0 or more, preferably 1.1 or more, and more preferably 1.2 or more. Thereby, application | coating operation by the squeegee etc. of an insulating paste becomes easy. On the other hand, the upper limit value of the thixo index is, for example, 3.0 or less, preferably 2.5 or less, and more preferably 2.0 or less. Thereby, the leveling property of insulating paste can be improved.

  The upper limit of the durometer hardness A defined in accordance with JIS K6253 (1997) of the elastomer of the insulating paste of the present embodiment (for example, a cured product of the insulating paste) may be, for example, 70 or less, Preferably it may be 68 or less, more preferably 65 or less. Thereby, in the elastomer of an insulating paste, a softness | flexibility can be improved and deformation | transformation, such as bending and expansion | extension, becomes easy. The lower limit of the durometer hardness A of the elastomer of the insulating paste is, for example, 10 or more, preferably 20 or more, and more preferably 30 or more. By using such an elastomer as the base substrate, the wiring formability on the base substrate surface can be improved. For example, variations in the shape and height of the wiring formed by printing such as screen printing can be suppressed.

  The lower limit value of the tensile strength measured in accordance with JIS K6251 (2004) of the elastomer of the insulating paste of the present embodiment (for example, a cured product of the insulating paste) is, for example, 5.0 MPa or more. Preferably it is 6.0 MPa or more, More preferably, it is 7.0 MPa or more. Thereby, the mechanical strength of the elastomer of the insulating paste can be improved. Further, the breaking energy can be increased. For this reason, the elastomer excellent in durability which can endure repeated deformation | transformation is realizable. On the other hand, the upper limit value of the tensile strength of the elastomer of the insulating paste is not particularly limited, but may be, for example, 15 MPa or less, or 13 MPa or less. Thereby, the balance between the elasticity of the elastomer of the insulating paste and the mechanical strength can be achieved.

  The lower limit of the tear strength measured in accordance with JIS K6252 (2001) of the elastomer of the insulating paste of the present embodiment (for example, a cured product of the insulating paste) is, for example, 25 N / mm or more, Preferably it is 30 N / mm or more, More preferably, it is 33 N / mm or more, More preferably, it is 35 N / mm or more. Thereby, durability and mechanical strength at the time of repeated use of the elastomer of the insulating paste can be improved. On the other hand, the upper limit value of the tear strength of the elastomer of the insulating paste is not particularly limited, but may be, for example, 70 N / mm or less, or 60 N / mm or less. Thereby, the various characteristics of the elastomer of the insulating paste of this embodiment can be balanced.

  In the present embodiment, for example, the viscosity, thixo index, hardness, tensile strength, and tear strength are selected by appropriately selecting the type and amount of each component contained in the insulating paste, the method for preparing the insulating paste, and the like. It is possible to control. Among these, for example, a hydrophobic solvent, a hydrocarbon solvent, a solvent having a high boiling point suitable for printing or a solvent having a small polar term or a small hydrogen bond term, and appropriately selecting the type of solvent, silica particles (C ) And the mixing ratio, the vinyl group-containing organopolysiloxane (A) having a vinyl group at the terminal is used to control the crosslink density of the resin and the uneven distribution of the crosslink structure, and the silane cup of the silica particles (C) The above-mentioned viscosity, thixo index, etc. can be caused to proceed more reliably with the silane coupling agent (D) and the silica particles (C) such as surface modification with the ring agent (D) and addition of water. , Hardness, tensile strength and tear strength are listed as elements for obtaining a desired numerical range.

(Insulating paste manufacturing method)
Hereinafter, the manufacturing method of the insulating paste according to the present embodiment will be described.

  The insulating paste of the present embodiment can be manufactured, for example, through the following processes.

  First, each component of the silicone rubber-based curable composition is uniformly mixed by an arbitrary kneading apparatus to prepare a silicone rubber-based curable composition.

[1] For example, a predetermined amount of vinyl group-containing organopolysiloxane (A), silica particles (C), and silane coupling agent (D) are weighed, and then kneaded by an arbitrary kneading apparatus. A kneaded product containing these components (A), (C), and (D) is obtained.

  The kneaded product is preferably obtained by kneading the vinyl group-containing organopolysiloxane (A) and the silane coupling agent (D) in advance, and then kneading (mixing) the silica particles (C). Thereby, the dispersibility of the silica particles (C) in the vinyl group-containing organopolysiloxane (A) is further improved.

  Moreover, when obtaining this kneaded material, you may make it add water (F) to the kneaded material of each component (A), (C), and (D) as needed. Thereby, reaction with a silane coupling agent (D) and a silica particle (C) can be advanced more reliably.

  Furthermore, kneading of the components (A), (C), and (D) is preferably performed through a first step of heating at the first temperature and a second step of heating at the second temperature. Thereby, in the first step, the surface of the silica particles (C) can be surface-treated with the coupling agent (D), and in the second step, the silica particles (C) and the coupling agent (D) By-products generated by the reaction can be reliably removed from the kneaded product. Thereafter, if necessary, the component (A) may be added to the obtained kneaded product and further kneaded. Thereby, the familiarity of the components of the kneaded product can be improved.

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

  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.

  Furthermore, the time of the first step is preferably, for example, about 0.3 to 1.5 hours, and more preferably about 0.5 to 1.2 hours. 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.

  By setting the first step and the second step as described above, the effect can be obtained more remarkably.

[2] Next, a predetermined amount of organohydrogenpolysiloxane (B) and platinum or platinum compound (E) are weighed, and then kneaded product prepared in the above step [1] using an arbitrary kneading apparatus. In addition, by kneading the components (B) and (E), a silicone rubber-based curable composition (elastomer composition) is obtained.

  When kneading each of the components (B) and (E), the kneaded material prepared in advance in the step [1] and the organohydrogenpolysiloxane (B) were prepared in the step [1]. It is preferable to knead the kneaded material and platinum or the platinum compound (E), and then knead each kneaded material. As a result, the components (A) to (E) are surely contained in the silicone rubber-based curable composition without causing a reaction between the vinyl group-containing organopolysiloxane (A) and the organohydrogenpolysiloxane (B). Can be dispersed.

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

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

  In the step [1] and the step [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) is more accurately performed. Can be prevented or suppressed. Moreover, in said process [1] and said process [2], by making kneading time into the said range, each component (A)-(E) can be more reliably disperse | distributed in a silicone rubber-type curable composition. Can do.

  The kneading apparatus used in each of the steps [1] and [2] is not particularly limited, and for example, a kneader, two rolls, a Banbury mixer (continuous kneader), a pressure kneader, or the like can be used.

  In this step [2], a reaction inhibitor such as 1-ethynylcyclohexanol may be added to the kneaded product. Thereby, even if the temperature of the kneaded product is set to a relatively high temperature, the progress of the reaction between the vinyl group-containing organopolysiloxane (A) and the organohydrogenpolysiloxane (B) is more accurately prevented or suppressed. be able to.

  [3] Next, the insulating paste of the present embodiment can be obtained by dissolving the elastomer composition (of the silicone rubber-based curable composition) obtained in the step [2] in a solvent.

[Usage]
Hereinafter, an example of the use of the insulating paste of the present embodiment will be described with reference to FIG. FIG. 1 shows a schematic cross-sectional view of an electronic device 100 having wiring.

  As illustrated in FIG. 1, the electronic device 100 can include a wiring board 50 and an electronic component 60. The wiring substrate 50 is configured by providing the wiring 10 on the substrate 20. As the substrate 20, an insulating substrate having elasticity can be used. This board | substrate 20 can be comprised with the hardened | cured material which hardened the insulating paste of this embodiment. The electronic component 60 may be configured to be electrically connected to the wiring 10 constituting such a stretchable wiring board (wiring board 50).

Since the insulating paste of this embodiment can maintain mechanical strength and durability when repeatedly stretched with respect to the obtained cured product, the structure of the electronic device 100 having excellent connection reliability is realized. Can do.
The electronic device 100 of this embodiment is used as a wearable device, for example, and can be suitably used for a device that is repeatedly expanded and contracted in each direction.

In addition, the wiring 10 constituting the electronic device 100 of the present embodiment is usually made of a flexible conductive material. The conductive material can include, for example, an elastomer composition and a conductive filler.
As this elastomer composition, the same elastomer composition as exemplified as the material of the above-described insulating paste can be employed. Specifically, an elastomer composition used to form silicone rubber, urethane rubber, fluorine rubber, nitrile rubber, acrylic rubber, styrene rubber, chloroprene rubber, ethylene propylene rubber, etc. can be used, depending on the application, etc. This material can be appropriately selected.

  The said wiring 10 may be comprised with the hardened | cured material of the electrically conductive paste containing said silicone rubber-type curable composition and an electroconductive filler.

As the conductive filler in the conductive paste, for example, a known conductive material may be used, but the following metal powder (G) can be included.
Although the metal which comprises this metal powder (G) is not specifically limited, For example, at least 1 type in copper, silver, gold | metal | money, nickel, tin, lead, zinc, bismuth, antimony, or the metal powder which alloyed these Alternatively, two or more of these can be included.
Among these, the metal powder (G) preferably contains silver or copper, that is, contains silver powder or copper powder because of its high conductivity and high availability. These metal powders (G) may be those coated with other types of metals.

  In this embodiment, although there is no restriction | limiting in the shape of metal powder (G), what was used conventionally, such as dendritic shape, spherical shape, and flake shape, can be used.

Further, in is not the particle size also limits the metal powder (G), for example, preferably has an average particle at diameter _{D 50} at 0.001μm, more preferably at 0.01μm or more, more preferably 0.1μm or more is there. The particle size of the metal powder (G) is, for example, is preferably 1,000μm less in average particle diameter _{D 50,} more preferably 100μm or less, more preferably 20μm or less.
By setting the average particle diameter D ₅₀ within such a range, it is possible to exert appropriate conductivity as the cured conductive paste. In addition, the particle size of the metal powder (G) is defined as an average value of 200 metal powders arbitrarily selected by conducting image analysis after observing the conductive paste or the cured product with a transmission electron microscope or the like, for example. can do.

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 50% by mass or more with respect to the entire conductive paste. Is more preferable. 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 65% by mass or less with respect to the entire conductive pace. More preferably.
By making content of metal powder (G) more than the said lower limit, the hardened | cured material of an insulating paste can have a moderate electroconductive characteristic. Moreover, hardened | cured material can have moderate softness | flexibility by making content of metal powder (G) below into the said upper limit.

  Further, the lower limit of the content of the silica particles (C) in the conductive paste is, for example, 1% by mass or more with respect to 100% by mass of the total amount of the silica particles (C) and the conductive filler, preferably Is 3% by mass or more, more preferably 5% by mass or more. Thereby, the mechanical strength of the hardened | cured material of an electrically conductive paste can be improved. 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 with respect to 100% by mass of the total amount of the silica particles (C) and the conductive fillers. , Preferably it is 15 mass% or less, More preferably, it is 10 mass% or less. Thereby, the balance of the expansion-contraction electrical property and mechanical strength in the hardened | cured material of an electrically conductive paste can be aimed at.

In the present embodiment, as the solvent for the conductive paste, the above-mentioned solvent types can be used, and among these, the solvent exhibiting solubility with respect to the insulating sheet which is a cured product of the insulating paste or the insulating paste. Can be used. As a specific solvent for the conductive paste, for example, a solvent having a high boiling point solvent or a HSP polar term (δ _p ) or hydrogen bond term (δ _h ) of the above upper limit or less can be used.

  The insulating paste of the present embodiment can be used for a substrate constituting a stretchable substrate provided with a stretchable wiring formed of a cured product of the conductive paste as described above, and an interlayer insulating layer between these wires.

  Further, the electronic component 60 may be appropriately selected from known components according to the application. Specifically, a semiconductor element, a resistor other than the semiconductor element, a capacitor, and the like can be given. Examples of semiconductor elements include transistors, diodes, LEDs, capacitors, and the like. In the electronic device 100 of this embodiment, the electronic component 60 is electrically connected by the wiring 10.

Moreover, the electronic apparatus 100 of this embodiment may be provided with the cover material 30 as needed. By providing this cover material 30, it is possible to prevent the wiring 10 and the electronic component 60 from being damaged. The cover material 30 may be configured to cover the electronic component 60 and the wiring 10 on the substrate 20.
Further, the cover material 30 can be made of the same material as the substrate 20. Since such a cover material 30 follows the expansion and contraction of the substrate 20 and the wiring 10, the entire electronic device 100 can be expanded and contracted without any deviation, and this can contribute to a longer life of the electronic device 100.

Next, an example of a manufacturing process of the electronic device 100 of this embodiment will be described with reference to FIG.
FIG. 2 is a cross-sectional view illustrating an outline of the manufacturing process of the electronic device 100 according to the present embodiment.

  First, as shown in FIG. 2A, a support body 120 is installed on a work table 110, and an insulating paste 130 is applied on the support body 120. Various methods can be used as the coating method. For example, a printing method such as a squeegee method using the squeegee 140 can be used. Subsequently, the coating-like insulating paste 130 can be dried to form the insulating layer 132 (dried insulating sheet) on the support 120. The drying conditions can be appropriately set according to the type and amount of the solvent in the insulating paste 130. For example, the drying temperature is 150 ° C. to 180 ° C. and the drying time is 1 minute to 30 minutes. it can.

  Subsequently, as illustrated in FIG. 2B, a mask 160 having a predetermined opening pattern shape is disposed on the insulating layer 132. Then, as shown in FIGS. 2B and 2C, the conductive paste 150 is applied on the insulating layer 132 through the mask 160. As the coating method, the same method as the coating method of the insulating paste 130 can be used. For example, squeegee printing using the squeegee 140 may be used. Here, when each of the insulating paste 130 and the conductive paste 150 includes a thermosetting elastomer composition, a conductive coating film (conductive layer 152) having a predetermined pattern shape is laminated on the dried insulating layer 132. These may be cured at once. Although it can set suitably as a hardening process according to a thermosetting elastomer composition, for example, hardening temperature can be 160 to 220 degreeC, hardening time can be 1 to 3 hours, etc. After the curing process or before the curing process, the mask 160 can be removed as shown in FIG. Thereby, the wiring which is the hardened | cured material of the conductive layer 152 which has a predetermined pattern shape on the board | substrate comprised with the hardened | cured material of the insulating layer 132 can be formed.

Subsequently, as shown in FIG. 2E, an insulating paste 170 is further applied on the insulating layer 132 and the patterned conductive layer 152, and the insulating layer 172 is applied as shown in FIG. Can be formed. These steps may be repeated as appropriate. In addition, the support 120 can be separated from the insulating layer 132.
Thus, the electronic device 100 illustrated in FIG. 2F can be obtained.

  In addition, when using an insulating sheet instead of an insulating paste, you may start from the process shown in FIG.2 (b). That is, an insulating sheet may be placed on the support 120 and dried, and then the conductive paste 150 may be applied to the insulating sheet through the mask 160. Subsequent steps can be performed according to the steps described above. As a result, it is possible to obtain the electronic device 100 shown in FIG.

  It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.

  Hereinafter, although an example and a comparative example explain the present invention, the present invention is not limited to these.

The materials used in Examples and Comparative Examples are as follows.
(Vinyl group-containing organopolysiloxane (A))
(A1-1): first vinyl group-containing linear organopolysiloxane: vinyl group content is 0.13 mol%, Mn = 227,734, Mw = 573,903, IV value (dl / g) = 0.89), vinyl group-containing dimethylpolysiloxane synthesized by the following synthesis scheme 1 (structure represented by the above formula (1-1))
(A1-2): second vinyl group-containing linear organopolysiloxane: vinyl group content is 0.92 mol%, vinyl group-containing dimethylpolysiloxane synthesized by the following synthesis scheme 2 (the above formula (1- 1) a structure in which R ¹ and R ² are vinyl groups

(Organohydrogenpolysiloxane (B))
(B1): Organohydrogenpolysiloxane: “88466” manufactured by Momentive

(Silica particles (C))
(C1): Silica fine particles (particle diameter 7 nm, specific surface area 300 m ² / g), manufactured by Nippon Aerosil Co., Ltd., “AEROSIL 300”

(Silane coupling agent (D))
(D1): Hexamethyldisilazane (HMDZ), manufactured by Gelest, “HEXAMETHYLDISILAZANE (SIH6110.1)”

(Platinum or platinum compound (E))
(E1): Platinum compound, PLATINUM DIVINYLTETRAMETHYLDISILOXAN COMPLEX (in xylen) (manufactured by Gelest, trade name “SIP6831.2”)

(Water (F))
(F1): Pure water

(Additive)
(Reaction inhibitor 1): 1-ethynyl-1-cyclohexanol (manufactured by Tokyo Chemical Industry Co., Ltd.)

(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 (7).
That is, Ar gas-substituted 300 mL separable flask having a cooling tube and a stirring blade was charged with 74.7 g (252 mmol) of octamethylcyclotetrasiloxane and 0.1 g of potassium siliconate, heated, and heated at 120 ° C. for 30 minutes. Stir. At this time, an increase in viscosity was confirmed.
Thereafter, the temperature was raised to 155 ° C. and stirring was continued for 3 hours. After 3 hours, 0.1 g (0.6 mmol) of 1,3-divinyltetramethyldisiloxane was added, and the mixture was further stirred at 155 ° C. for 4 hours.
Further, after 4 hours, the mixture was diluted with 250 mL of toluene and then washed with water three times. The washed organic layer was washed several times with 1.5 L of methanol, and purified by reprecipitation to separate the oligomer and polymer. The obtained polymer was dried under reduced pressure at 60 ° C. overnight to obtain a first vinyl group-containing linear organopolysiloxane (A1-1) (Mw = 573,903, Mn = 227,734). The vinyl group content calculated by H-NMR spectrum measurement was 0.13 mol%.

[Synthesis Scheme 2: Synthesis of Second Vinyl Group-Containing Linear Organopolysiloxane (A1-2)]
In the synthesis step (A1-1), in addition to 74.7 g (252 mmol) of octamethylcyclotetrasiloxane, 2,4,6,8-tetramethyl 2,4,6,8-tetravinylcyclotetrasiloxane The second vinyl group-containing linear organopolysiloxane (A1-2) was obtained by the same method as in the synthesis step (A1-1) except that 86 g (2.5 mmol) was used. ) Was synthesized. The vinyl group content calculated by H-NMR spectrum measurement was 0.92 mol%.

[Preparation of insulating paste]
(Preparation of silicone rubber-based curable compositions 1 to 3)
Silicone rubber-based curable compositions 1 to 3 were prepared as follows. First, a mixture of 90% vinyl group-containing organopolysiloxane (A), silane coupling agent (D) and water (F) was kneaded in advance at the ratio shown in Table 1 below, and then silica particles ( C) was added and further kneaded to obtain a kneaded product (silicone rubber compound).
Here, the kneading after the addition of the silica particles (C) includes the first step of kneading for 1 hour under the condition of 60 to 90 ° C. in a nitrogen atmosphere for the coupling reaction, and the removal of the by-product (ammonia). Therefore, the second step of kneading for 2 hours under the condition of 160 to 180 ° C. in a reduced-pressure atmosphere is performed, and then cooled, and the remaining 10% of the vinyl group-containing organopolysiloxane (A) is added twice. Add in portions and knead for 20 minutes.
Subsequently, organohydrogenpolysiloxane (B), platinum or a platinum compound (E) and a reaction inhibitor were added to 100 parts by weight of the obtained kneaded material (silicone rubber compound) at the ratio shown in Table 1 below. And kneading with a roll to obtain silicone rubber-based curable compositions 1 to 3 (elastomer compositions 1 to 3).

(Elastomer composition 4)
As the elastomer composition 4, a trade name “C6-135 ELASTOMER (including silica particles)” manufactured by Toray Dow Corning Co., Ltd. was used.

(Elastomer composition 5)
Silica particles surface-treated with 9.2 g of urethane diacrylate (trade name “Aronix M-1200” manufactured by Toagosei Co., Ltd.) and 0.9 g of silane coupling agent (hexamethyldisilazane (manufactured by Gelest)) 3.5 g (manufactured by Nippon Aerosil Co., Ltd., trade name “AEROSIL300”) and 0.1 g of an organic peroxide initiator (trade name “Perhexa 3M” produced by Nippon Oil & Fats Co., Ltd.) were mixed to obtain an elastomer composition 5. .

<Example 1: Insulating paste 1>
The obtained 32 parts by weight of the silicone rubber-based curable composition 1 (elastomer composition 1) was immersed in 68 parts by weight of tetradecane, and then stirred with a rotation / revolution mixer to obtain a liquid insulating paste 1. It was.

<Example 2: Insulating paste 2>
The obtained 32 parts by weight of the silicone rubber-based curable composition 2 (elastomer composition 2) is immersed in 68 parts by weight of decane, and then stirred with a rotation / revolution mixer to obtain a liquid insulating paste 2. It was.

<Example 3: Insulating paste 3>
The obtained 32 parts by weight of the silicone rubber-based curable composition 1 (elastomer composition 1) is immersed in 68 parts by weight of toluene, followed by stirring with a rotating / revolving mixer to obtain a liquid insulating paste 3. It was.

<Example 4: Insulating paste 4>
The obtained 32 parts by weight of the elastomer composition 4 (containing 7.0 parts by weight of silica particles) was immersed in 68 parts by weight of decane, and then stirred by a rotating / revolving mixer to obtain a liquid insulating paste 4 Got.

<Example 5: Insulating paste 5>
The obtained 32 parts by weight of the elastomer composition 5 was immersed in 68 parts by weight of toluene, and then stirred with a rotating / revolving mixer to obtain a liquid insulating paste 5.

<Example 6: Insulating paste 6>
The obtained 32 parts by weight of the elastomer composition 1 was immersed in 68 parts by weight of mesitylene and then stirred by a rotating / revolving mixer to obtain a liquid insulating paste 6.

<Example 7: Insulating paste 7>
The obtained 32 parts by weight of the elastomer composition 2 was immersed in 68 parts by weight of dipropylene glycol dimethyl ether, followed by stirring with a rotation / revolution mixer to obtain a liquid insulating paste 7.

<Example 8: Insulating paste 8>
The obtained 32 parts by weight of the elastomer composition 1 was immersed in 68 parts by weight of diethyl carbonate, and then stirred with a rotating / revolving mixer to obtain a liquid insulating paste 8.

<Example 9: Insulating paste 9>
The obtained 20 parts by weight of the elastomer composition 1 was immersed in 80 parts by weight of tetradecane, and then stirred with a rotating / revolving mixer to obtain a liquid insulating paste 9.

<Example 10: Insulating paste 10>
The obtained 40 parts by weight of the elastomer composition 2 was immersed in 60 parts by weight of decane, and then stirred with a rotating / revolving mixer to obtain a liquid insulating paste 10.

<Comparative Example 1: Elastomer composition>
The obtained 100 parts by weight of the elastomer composition 1 (containing 25.6 parts by weight of silica particles (C)) was used as it was as a comparative example 1 sample without being immersed in a solvent.

<Comparative Example 2: Insulating paste 11>
The obtained 32 parts by weight of the elastomer composition 3 (excluding silica particles (C)) was immersed in 68 parts by weight of tetradecane and then stirred with a rotation / revolution mixer to obtain a liquid insulating paste 11. It was.

In the solubility parameter (HSP) of Hansen as a solvent in Table 2, tetradecane dispersion term (δ _d ): 15.8 MPa ^1/2 , polar term (δ _p ): 0 MPa ^1/2 , hydrogen bond term (δ _h ) : 0 MPa ^1/2 , decane dispersion term (δ _d ): 15.7 MPa ^1/2 , polar term (δ _p ): 0 MPa ^1/2 , hydrogen bond term (δ _h ): 0 MPa ^1/2 , dispersion term of toluene (δ _d): 17.8MPa ^1/2, polarity term (δ _p): 3.0MPa ^1/2, hydrogen bond (δ _h): ^{0MPa 1/2,} dispersion term of mesitylene (Δ _d ): 18.0 MPa ^1/2 , polar term (δ _p ): 0.6 MPa ^1/2 , hydrogen bond term (δ _h ): 0.6 MPa ^1/2 , dispersion term of dipropylene glycol dimethyl ether (δ _d): 15.1MPa ^1/2, Sexual terms (δ _p): 6.3MPa ^1/2, hydrogen bond (δ _h): 4.9MPa ^1/2, dispersion term of diethyl carbonate (δ _d): 15.7MPa ^1/2, polarity term (Δ _p ): 5.1 MPa ^1/2 , hydrogen bond term (δ _h ): 3.5 MPa ^1/2 Tetradecane has a boiling point of 253 ° C., decane has a boiling point of 174 ° C., toluene has a boiling point of 111 ° C., mesitylene has a boiling point of 165 ° C., and dipropylene glycol dimethyl ether has a boiling point of 175 ° C. The boiling point of diethyl carbonate was 126 ° C.
Further, “−” of Comparative Example 1 in Table 2 indicates that each evaluation item could not be measured because the coating operation could not be performed on the sample of Comparative Example 1. Therefore, it was judged that the sample of Comparative Example 1 could not be used as a paste and the coating property (film forming property) was poor.

[Evaluation of insulating paste]
The obtained insulating pastes 1 to 11 and Comparative Example 1 samples were evaluated according to the following items.
Tensile strength was measured using three samples, and three average values were used as measured values. Moreover, about tear strength, it carried out with five samples and made five average values into the measured value. Furthermore, about hardness, it measured by n = 5 with each sample using 2 samples, and made the average value of 10 measurements into the measured value. The average value is shown in Table 2 for each.

<Production of sheet elastomer>
About the obtained insulating pastes 1 to 11 and Comparative Example 1 samples, using a bar coater, they were applied to a 100 × 100 mm size on a release-treated aluminum foil and cured at 170 ° C. for 120 minutes. Then, it was peeled from the aluminum foil to prepare a sheet-like elastomer for use in each evaluation.

<Viscosity>
About the obtained insulating paste, the viscosity in shear rate 20 [1 / s] in room temperature 25 degreeC was measured immediately after preparation of insulating paste using TPE-100H by Toki Sangyo Co., Ltd. The unit of viscosity is Pa · s.
<Thixo index>
About the obtained insulating paste, the viscosity when measured at a shear rate of 1 [1 / s] at a room temperature of 25 ° C. using TPE-100H manufactured by Toki Sangyo Co., Ltd. is η1, and the shear rate is 5 [1 / s. ] Was measured as immediately after the production of the insulating paste. The unit of viscosity is Pa · s. The thixo index was determined as the viscosity ratio (η1 / η5).

<Tensile strength>
Using the obtained sheet-like elastomers of Examples and Comparative Examples having a thickness of 1 mm, dumbbell-shaped No. 3 test pieces were prepared according to JIS K6251 (2004), and the obtained dumbbell-shaped No. 3 was obtained. The tensile strength at room temperature of 25 ° C. of the shape test piece was measured. The unit is MPa.

<Tear strength>
Using the obtained sheet-like elastomer of each Example and Comparative Example having a thickness of 1 mm, a crescent-shaped test piece was prepared in accordance with JIS K6252 (2001), and the room temperature of the obtained crescent-shaped test piece was 25. The tear strength at 0 ° C. was measured. The unit is N / mm.

<Hardness: Durometer hardness A>
Six sheet-shaped elastomers of each Example and Comparative Example having a thickness of 1 mm were laminated to prepare a 6 mm test piece. The type A durometer hardness at room temperature of 25 ° C. was measured on the obtained test piece in accordance with JIS K6253 (1997).

<Evaluation of film formability>
About each insulation paste of an Example and a comparative example, it apply | coats to a 100x100 mm size on a glass substrate using a bar coater, and the thickness after hardening enters into the range of about 100 micrometers in 170 degreeC and 120 minutes. A film was formed. Thickness measurement is performed at the center and four corners of the obtained coating film, and the variation (maximum film thickness value−minimum film thickness value) is evaluated, and the variation is 10 μm or less, ◎, 20 μm or less, and larger than 20 μm. X. The results are shown in Table 2.

<Extension durability>
Using the obtained 1 mm sheet-like elastomer, a dumbbell-shaped No. 3 test piece was prepared in accordance with JIS K6251 (2004).
Next, the following tensile repetition test was performed. The results are shown in Table 2.
When the obtained dumbbell-shaped No. 3 test piece was stretched to 500%, ◎ indicates that it can be stretched 500%, ○ indicates that it can be stretched 200%, and x indicates that it can stretch 200% or less. did.
Testing machine: Autograph AG5kNX (manufactured by Shimadzu Corporation, “Model No. AG-5kNX”)
-Initial value: 60 mm (distance between chucks), 0% elongation rate-During elongation: 360 mm (distance between chucks), 500% elongation rate-Elongation rate: Maximum speed 1,000 mm / min

  The insulating paste obtained in each of Examples 1 to 10 is excellent in coating property (film forming property) as compared with Comparative Example 1, and is excellent in extension durability as compared with Comparative Example 2. Furthermore, it was found that an insulating resin film excellent in mechanical strength such as tensile strength and tear strength can be obtained. It has been found that the insulating pastes of Examples 1 to 10 are suitable for forming a stretchable substrate.

DESCRIPTION OF SYMBOLS 10 Wiring 20 Board | substrate 30 Cover material 50 Wiring board 60 Electronic component 100 Electronic apparatus 110 Work stand 120 Support body 130 Insulating paste 132 Insulating layer 140 Squeegee 150 Conductive paste 152 Conductive layer 160 Mask 170 Insulating paste 172 Insulating layer

Claims (17)

An elastomer composition containing silica particles (C);
And an insulating paste containing a solvent. The insulating paste according to claim 1,
An insulating paste, wherein the elastomer composition comprises a thermosetting elastomer composition for forming one or more elastomers selected from the group consisting of silicone rubber, urethane rubber, and fluororubber. The insulating paste according to claim 1 or 2,
An insulating paste used to form a substrate constituting a stretchable wiring substrate. The insulating paste according to any one of claims 1 to 3,
An insulating paste, wherein the solvent includes a high boiling point solvent having a boiling point of 100 ° C. or higher and 300 ° C. or lower. The insulating paste according to any one of claims 1 to 4,
An insulating paste, wherein the solvent contains an aliphatic hydrocarbon having 5 to 20 carbon atoms. An insulating paste according to any one of claims 1 to 5,
An insulating paste, wherein the solvent includes a first solvent having a polarity term (δ _p ) of a Hansen solubility parameter of 10 MPa ^1/2 or less. The insulating paste according to any one of claims 1 to 6,
An insulating paste having a viscosity of 1 Pa · s or more and 100 Pa · s or less at a room temperature of 25 ° C. The insulating paste according to any one of claims 1 to 7,
For the insulating paste at room temperature 25 ° C., the viscosity ratio when the viscosity when measured at a shear rate of 1 [1 / s] is η1 and the viscosity when measured at a shear rate of 5 [1 / s] is η5. An insulating paste having a thixotropic index (η1 / η5) of 1.0 or more and 3.0 or less. The insulating paste according to any one of claims 1 to 8,
The insulating paste whose content of the said silica particle (C) is 1 to 50 mass% with respect to the said whole insulating paste. The insulating paste according to any one of claims 1 to 9,
An insulating paste, wherein the elastomer composition comprises a silicone rubber-based curable composition. The insulating paste according to claim 10,
An insulating paste, wherein the silicone rubber-based curable composition contains a vinyl group-containing organopolysiloxane (A). The insulating paste according to claim 10 or 11,
An insulating paste, wherein the silicone rubber-based curable composition further comprises an organohydrogenpolysiloxane (B). The insulating paste according to any one of claims 10 to 12,
An insulating paste, wherein the silicone rubber-based curable composition further comprises platinum or a platinum compound (E). The insulating paste according to any one of claims 1 to 13,
The insulating paste whose content of the said elastomer composition is 5 to 50 mass% with respect to the said insulating paste whole. The insulating paste according to any one of claims 1 to 14,
The insulating paste whose durometer hardness A prescribed | regulated based on JISK6253 (1997) of the elastomer which consists of the said insulating paste is 10-70. The insulating paste according to any one of claims 1 to 15,
The insulating paste whose tensile strength measured according to JISK6251 (2004) of the elastomer which consists of the said insulating paste is 5.0 MPa or more and 15 MPa or less. The insulating paste according to any one of claims 1 to 16,
The insulating paste whose tear strength measured according to JIS K6252 (2001) of the elastomer which consists of the said insulating paste is 25 N / mm or more.

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