JP2018021189A - Prepreg, and resin plate, metal-clad laminate, printed wiring board and semiconductor device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a prepreg which can prepare a resin plate, a metal-clad laminate and the like having heat resistance and contains a siloxane resin composition, and to provide a resin plate, a metal-clad laminate, a printed wiring board and a semiconductor device using the same.SOLUTION: A prepreg contains a fiber base material and a siloxane resin composition, where the siloxane resin composition contains at least component (A): a polysiloxane compound containing at least two or more functional groups selected from the group consisting of a silanol group and an alkoxysilyl group in one molecule and component (B): silica having a pH value of extracted water at 25°C of 6.1 or less, and a ratio of the component (B) to the total amount of the component (A) and the component (B) is 70 mass% or more and 97 mass% or less.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a prepreg, and a resin plate, a metal-clad laminate, a printed wiring board, and a semiconductor device using the prepreg.

  With the increase in functionality and performance of electronic devices, the amount of heat generated by semiconductor chips tends to increase. For example, in power semiconductors used for power and power supply control, devices that incorporate silicon carbide (SiC) semiconductor elements or gallium nitride (GaN) semiconductor elements instead of conventional silicon semiconductor elements are the next generation power. Expected to be a semiconductor. In these devices, it is said that the performance can be fully extracted by a stable operation at about 250 ° C. In connection with this, the heat-resistant temperature requested | required of the board | substrate which mounts a semiconductor chip is also increasing.

  2. Description of the Related Art Currently, substrates that are formed into a plate shape by impregnating an organic resin into a fiber base material such as glass cloth and drying are widely used as substrates used in the semiconductor mounting field. As the organic resin, phenol resin and epoxy resin are most commonly used. From the viewpoint of improving heat resistance, bismaleimide-triazine resin (referred to as BT resin), polyphenylene ether resin (referred to as PPE resin), etc. Organic resins are also used. These substrates are often designed with the operating temperature of silicon semiconductor elements as a guide (for example, 175 ° C.), and heat resistance is still sufficient in mounting semiconductor elements capable of high-temperature operation such as SiC semiconductors and GaN semiconductors. is not.

  Ceramics have been used as a substrate used in the semiconductor mounting field, but it has excellent heat resistance, but is expensive and cannot be used for large substrates. Then, it is excellent in characteristics, such as heat resistance and a weather resistance, and using the resin board and metal-clad laminated board using the prepreg by the siloxane resin currently used for various uses is examined.

  Patent Document 1 discloses a prepreg using an addition-curable siloxane resin composition, a resin plate using the prepreg, and the like, and discloses a prepreg in which a specific hard silicone resin is impregnated in a quartz glass cloth. Has been.

JP 2013-95862 A

  An object of the present invention is to provide a prepreg that can suppress foaming during curing and has high heat resistance, and a resin plate, a metal-clad laminate, a printed wiring board, and a semiconductor device using the prepreg.

  As a result of intensive studies to achieve the above object, the present inventors have focused on using a condensation curable siloxane resin composition instead of an addition curable siloxane resin composition. In the condensation curable type, the obtained cured product can be expected to have heat resistance equal to or higher than that of the addition curable type due to the nature of the curing reaction.

  However, it has been found that in the condensation curing type curing reaction, gas is generated during curing and foaming may occur in the cured product. This foaming not only causes molding defects, but can also lead to a decrease in adhesion, mechanical strength, gas barrier properties, insulating properties, and the like. However, due to the nature of the condensation reaction, the solution has been essentially difficult.

Therefore, as a result of further intensive studies by the inventors,
A prepreg comprising a fiber substrate and a siloxane resin composition,
The siloxane resin composition is
(A) component: a predetermined polysiloxane compound, and (B) component: at least silica having a pH value of extracted water at 25 ° C. of 6.1 or less, with respect to the total amount of (A) component and (B) component In order to complete the present invention, it is found that by using a prepreg characterized in that the ratio of the component (B) is 70% by mass or more and 97% by mass or less, the occurrence of foaming can be suppressed and the above-mentioned problems can be achieved. It came.

  That is, the present invention includes the following inventions.

[Invention 1]
A prepreg comprising a fiber substrate and a siloxane resin composition,
The siloxane resin composition is
(A) component: a polysiloxane compound containing at least two functional groups selected from the group consisting of a silanol group and an alkoxysilyl group in one molecule;
And (B) component: containing at least silica whose pH value of the extracted water is 6.1 or less at 25 ° C.
The prepreg whose ratio of (B) component with respect to the total amount of (A) component and (B) component is 70 mass% or more and 97 mass% or less.

[Invention 2]
The prepreg according to invention 1, wherein the component (A) comprises a polysiloxane compound having at least a structural unit represented by the following formula [1].

(In Formula [1], each R ¹ is independently a hydrogen atom, a linear alkyl group having 1 to 10 carbon atoms, a branched alkyl group having 3 to 10 carbon atoms, or a cyclic alkyl group having 3 to 10 carbon atoms. Group, a linear alkenyl group having 2 to 10 carbon atoms, a branched alkenyl group having 3 to 10 carbon atoms, a cyclic alkenyl group having 3 to 10 carbon atoms, or an aryl group having 5 to 10 carbon atoms, and Some or all of the hydrogen atoms in the alkyl group, alkenyl group, or aryl group may be substituted with halogen atoms, and some of the carbon atoms in the alkyl group, alkenyl group, or aryl group may be nitrogen atoms, oxygen atoms, and It may be substituted with at least one selected from the group consisting of silicon atoms, and the halogen atom is at least one selected from the group consisting of fluorine atoms, chlorine atoms, bromine atoms and iodine atoms In the case where a plurality of R ¹ are present, R ¹ may be the same or different from each other, and at least one oxygen atom in the formula [1] is an oxygen that forms a siloxane bond. (It is an atom and may form a silanol group or an alkoxysilyl group. M and n in the formula [1] each represents an integer of 1 to 3, and satisfies m + n = 4.)

[Invention 3]
R ¹ represents a linear alkyl group having 1 to 10 carbon atoms, a branched alkyl group having 3 to 10 carbon atoms, a cyclic alkyl group having 3 to 10 carbon atoms, or an aryl group having 5 to 10 carbon atoms. The prepreg according to invention 2.

[Invention 4]
The prepreg according to invention 2, wherein R ¹ represents a methyl group or a phenyl group.

[Invention 5]
The prepreg according to any one of Inventions 2 to 4, wherein the component (A) comprises a polysiloxane compound having a structural unit represented by the formula [1] and a structural unit represented by the following formula [2]. .

(The oxygen atoms in the formula [2] each represent an oxygen atom forming a siloxane bond, or an oxygen atom forming a silanol group or an alkoxysilyl group.)

[Invention 6]
The prepreg according to any one of Inventions 1 to 5, wherein the total content of silanol groups and alkoxysilyl groups in the component (A) is 1 mmol / g or more and 15 mmol / g or less.

[Invention 7]
The prepreg according to any one of Inventions 1 to 6, wherein the component (B) contains silica particles having a particle diameter of 3 μm or less.

[Invention 8]
(B) The prepreg as described in any one of invention 1 thru | or 7 whose component is a silica which shows a some frequency peak in a particle size distribution measurement.

[Invention 9]
The prepreg according to any one of Inventions 1 to 8, wherein the component (B) is silica whose surface is not chemically modified.

[Invention 10]
A method for producing a prepreg comprising a fiber substrate and a siloxane resin composition,
(A) component: a polysiloxane compound containing at least two functional groups selected from the group consisting of a silanol group and an alkoxysilyl group in one molecule;
(B) component: the process of obtaining this siloxane resin composition by mixing at least the silica whose pH value of extraction water is 6.1 or less in 25 degreeC,
Impregnating and drying the siloxane resin composition on the fiber substrate,
The manufacturing method of a prepreg whose ratio of (B) component with respect to the total amount of (A) component and (B) component is 70 to 97 mass%.

[Invention 11]
A method for producing a prepreg comprising a fiber substrate and a siloxane resin composition,
The siloxane resin composition is
(A) component: a polysiloxane compound containing at least two functional groups selected from the group consisting of a silanol group and an alkoxysilyl group in one molecule;
(B) component: Silica whose pH value of extraction water is 6.1 or less at 25 ° C.,
Including
The ratio of the component (B) to the total amount of the component (A) and the component (B) is 70% by mass or more and 97% by mass or less, and is a siloxane resin composition.
A method for producing a prepreg, comprising a step of impregnating the fiber substrate with the siloxane resin composition and drying.

[Invention 12]
A molded body of the prepreg according to any one of the inventions 1 to 9 or a laminate of the prepreg.

[Invention 13]
A resin plate comprising the molded article according to invention 12.

[Invention 14]
A metal-clad laminate comprising a resin layer comprising the resin plate according to invention 13 and a metal layer.

[Invention 15]
A metal-clad laminate comprising the resin plate according to the invention 13 and a metal foil on both sides or one side of the resin plate.

[Invention 16]
A printed wiring board comprising the resin board according to the invention 13 and a wiring pattern on both sides or one side of the resin board.

[Invention 17]
A semiconductor device comprising the printed wiring board according to the sixteenth aspect of the present invention and a semiconductor element installed on the printed wiring board.

  By using the prepreg of the present invention, foaming when the prepreg is molded into a resin plate, a metal-clad laminate, or the like can be suppressed, and a heat-resistant resin plate, a metal-clad laminate, or the like can be produced. A resin plate, a metal-clad laminate, and a printed wiring board using the prepreg of the present invention are useful, for example, as a substrate for mounting a semiconductor element, particularly as a substrate for mounting a power semiconductor element.

It is a schematic sectional drawing which shows an example of the semiconductor device of this invention.

  Hereinafter, embodiments of the present invention will be described, but the technical scope of the present invention should be determined based on the description of the scope of claims, and is not limited by the following specific embodiments.

[Siloxane resin composition]
The siloxane resin composition used in the present invention contains at least a predetermined polysiloxane compound as the component (A) and a predetermined silica as the component (B). The siloxane resin composition of the present invention may further contain a predetermined additive as the other component.

  Hereinafter, each component contained in the siloxane resin composition used in the present invention will be described in detail.

<(A) component: polysiloxane compound>
(First embodiment)
The component (A) is a polysiloxane compound containing at least two functional groups selected from the group consisting of silanol groups and alkoxysilyl groups in one molecule.

  The type of the polysiloxane compound is not particularly limited as long as it is a polysiloxane compound containing at least two functional groups selected from the group consisting of silanol groups and alkoxysilyl groups in one molecule. You may use, and may use 2 or more types together. Such a polysiloxane compound is obtained by hydrolytic polycondensation of at least one selected from the group consisting of alkoxysilane compounds and chlorosilane compounds. At this time, in addition to at least one selected from the group consisting of alkoxysilane compounds and chlorosilane compounds, hydrolytic polycondensation may be carried out using a cyclic siloxane compound or a polydimethylsiloxane compound in combination.

The component (A) according to the present invention is selected from the group consisting of a silanol group and an alkoxysilyl group from the viewpoint of obtaining a substrate suitable for mounting a substrate for mounting a semiconductor element, particularly a substrate for mounting a power semiconductor element. A polysiloxane compound containing at least two functional groups in one molecule and having at least a structural unit represented by the following formula [1] (hereinafter sometimes referred to as “polysiloxane compound [1]”) .). However, you may use polysiloxane compounds other than polysiloxane compound [1] as a part of (A) component.

In formula [1], each R ¹ is independently a hydrogen atom, a linear alkyl group having 1 to 10 carbon atoms, a branched alkyl group having 3 to 10 carbon atoms, or a cyclic alkyl group having 3 to 10 carbon atoms. , A linear alkenyl group having 2 to 10 carbon atoms, a branched alkenyl group having 3 to 10 carbon atoms, a cyclic alkenyl group having 3 to 10 carbon atoms, or an aryl group having 5 to 10 carbon atoms. Some or all of the hydrogen atoms in these alkyl groups, alkenyl groups or aryl groups may be substituted with halogen atoms, and some of the carbon atoms in the alkyl group, alkenyl group or aryl group are nitrogen atoms, oxygen It may be substituted with at least one selected from the group consisting of atoms and silicon atoms. Here, the halogen atom represents at least one selected from the group consisting of a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. When a plurality of R ¹ are present, R ¹ may be the same or different from each other. In formula [1], at least one oxygen atom is an oxygen atom forming a siloxane bond, and may form a silanol group or an alkoxysilyl group. In the formula [1], m and n each represent an integer of 1 to 3, and satisfy m + n = 4.

Examples of the linear alkyl group having 1 to 10 carbon atoms, the branched alkyl group having 3 to 10 carbon atoms, or the cyclic alkyl group having 3 to 10 carbon atoms in R ¹ of the formula [1] include methyl group, ethyl Group, propyl group, butyl group, hexyl group, octyl group, decyl group, isopropyl group, isobutyl group, sec-butyl group, tert-butyl group, cyclohexyl group and the like. Of these, a methyl group is preferable.

Examples of the linear alkenyl group having 2 to 10 carbon atoms, the branched alkenyl group having 3 to 10 carbon atoms, or the cyclic alkenyl group having 3 to 10 carbon atoms in R ¹ of the formula [1] include a vinyl group and an allyl group Groups and the like.

The aryl group having 5 to 10 carbon atoms in ^{R 1} of the formula [1], a phenyl group, 1-naphthyl, 2-naphthyl and the like. Of these, a phenyl group is preferred.

From the viewpoint of enhancing the curability of the siloxane resin composition and further suppressing cracks in resin plates and metal-clad laminates, the structural unit represented by the above formula [1] has R ¹ having 1 to 10 carbon atoms. It preferably includes a structural unit representing a linear alkyl group, a branched alkyl group having 3 to 10 carbon atoms, a cyclic alkyl group having 3 to 10 carbon atoms, or an aryl group having 5 to 10 carbon atoms. Among these, it is particularly preferable that R ¹ includes a structural unit representing a methyl group or a phenyl group.

In the polysiloxane compound [1], when m is 2 and n is 2, a structural unit represented by [R ¹ ₂ SiO _2/2 ] (hereinafter referred to as “bifunctional structural unit”) Is a structure represented by the following formula [1-2], that is, a structure in which one of oxygen atoms bonded to a silicon atom in a bifunctional structural unit constitutes a hydroxy group or an alkoxy group ( In the relationship with a silicon atom, it means a structure constituting a silanol group or an alkoxysilyl group (the same applies in this specification).

In the formula [1-2], X represents a hydroxy group or an alkoxy group, ^{R 1} has the same meaning as ^{R 1} in the formula [1].

The bifunctional structural unit includes a portion surrounded by a broken line of the structural unit represented by the following formula [1-b], and is further surrounded by a broken line of the structural unit represented by the following formula [1-2-b]. May include a portion. That is, a structural unit having a group represented by R ¹ and having a hydroxy group or an alkoxy group remaining at the terminal is also included in the bifunctional structural unit. Specifically, when the alkoxy group of the alkoxysilane compound that can be a raw material of the component (A) remains in the component (A) or is converted into a hydroxy group, or the chlorine atom of the chlorosilane compound is converted into a hydroxy group. In some cases, the bifunctional structural unit having a hydroxy group or an alkoxy group represents a portion surrounded by a broken line of the structural unit represented by the following formula [1-2-b]. In the structural unit represented by the following formula [1-b], the oxygen atom in the Si—O—Si bond forms a siloxane bond with the adjacent silicon atom, and the adjacent structural unit and oxygen atom Sharing. Accordingly, one oxygen atom in the Si—O—Si bond is defined as “O _1/2 ”.

In the above formula [1-2-b], X represents a hydroxy group or an alkoxy group. ^{R 1} in the formula [1-b] and [1-2-b] has the same meaning as ^{R 1} in the formula [1].

In the polysiloxane compound [1], when m is 1 and n is 3, a structural unit represented by [R ¹ SiO _3/2 ] (hereinafter referred to as “trifunctional structural unit”) Is a structure represented by the following formula [1-3] or [1-4], that is, two or one of the oxygen atoms bonded to the silicon atom in the trifunctional structural unit are each hydroxy. The structure which comprises a group or an alkoxy group may be included.

In the above formulas [1-3] and [1-4], X represents a hydroxy group or an alkoxy group, and in the formula [1-3], a plurality of Xs may be the same or different from each other. In the formula [1-3] and [1-4], ^{R 1} has the same meaning as ^{R 1} in the formula [1].

The trifunctional structural unit includes a portion surrounded by a broken line of the structural unit represented by the following formula [1-c], and is further represented by the following formula [1-3-c] or [1-4-c]. A portion surrounded by a broken line of the structural unit may be included. That is, a structural unit having a group represented by R ¹ and having a hydroxy group or an alkoxy group or both remaining at the terminal is also included in the trifunctional structural unit.

In the above formulas [1-3-c] and [1-4-c], X represents a hydroxy group or an alkoxy group, and in the formula [1-3-c], a plurality of Xs are the same or different from each other. There may be. The formula [1-c], ^{R 1} in the [1-3-c] and [1-4-c] has the same meaning as ^{R 1} in the formula [1].

  The polysiloxane compound [1] may include a plurality of structural units represented by the formula [1], and these structural units may be the same or different types. From the viewpoint that the cured product prepared from the polysiloxane compound [1] is likely to exhibit high heat resistance and high adhesion to various members, the content of the bifunctional structural unit in the polysiloxane compound [1] is 0% or more and 98. % Or less, and in the polysiloxane compound [1], the content of the trifunctional structural unit is preferably 0% or more and 100% or less.

In addition to the structural unit represented by the formula [1], the polysiloxane compound [1] may further include a polysiloxane compound having a structural unit represented by the following formula [2]. When the polysiloxane compound [1] contains a polysiloxane compound having a structural unit represented by the following formula [2] in addition to the structural unit represented by the formula [1], a resin plate or a metal obtained This is preferable in that the heat resistance of the stretched laminate and the like is further improved and good adhesion with various members is easily exhibited. Hereinafter, the polysiloxane compound having the structural unit represented by the formula [1] and the structural unit represented by the formula [2] may be referred to as “polysiloxane compound [2]”.

In the formula [2], each oxygen atom represents an oxygen atom forming a siloxane bond or an oxygen atom of a hydroxy group.

In the polysiloxane compound [2], the ratio of the structural unit represented by the formula [1] and the structural unit represented by the formula [2] is not particularly limited. From the viewpoint of easy production so that the mass average molecular weight falls within a preferred range, (number of [SiO _4/2 ]) / (number of [R ¹ _m SiO _{n / 2} ]) is 1 or less. It is preferable that m and n each represent an integer of 1 to 3, and m + n = 4 is satisfied.

  The mass average molecular weight of the component (A) according to the present invention is not particularly limited. Usually, it may be 200 or more and 50,000 or less. (B) Since it has fluidity | liquidity sufficient to mix | blend with a component favorably, 300 or more and 10,000 or less are preferable and 600 or more and 3,000 or less are especially preferable. Here, the mass average molecular weight is a value obtained by measuring by gel permeation chromatography (hereinafter sometimes referred to as GPC) and converting it with a standard polystyrene calibration curve.

  The total content of silanol groups and alkoxysilyl groups in component (A) is not particularly limited, but is preferably in the range of 1 mmol / g to 15 mmol / g, and preferably in the range of 3 mmol / g to 15 mmol / g. It is particularly preferred.

  In the siloxane resin composition of the present invention, when the total content of silanol groups and alkoxysilyl groups in the component (A) is less than 1 mmol / g, the amount of silanol groups and alkoxysilyl groups is small and the curing reaction is insufficient. When the amount is more than 15 mmol / g, the amount of silanol group and alkoxysilyl group becomes excessive and foaming tends to occur. Therefore, in the range of 1 mmol / g or more and 15 mmol / g or less, the curing reaction of the siloxane resin composition proceeds smoothly, and a resin plate or a metal-clad laminate in which foaming is particularly suppressed can be obtained. Further, when the total content of silanol groups and alkoxysilyl groups is within this range, the dispersibility of the component (B) in the siloxane resin composition used in the present invention becomes good, and the siloxane resin composition further contains an inorganic filler. When it contains, the dispersibility of an inorganic filler also becomes favorable. Thereby, the siloxane resin composition used in the present invention maintains good dispersion stability over a long period of time. Furthermore, if the total content of silanol groups and alkoxysilyl groups is within this range, the resin plate using the prepreg of the present invention shows good adhesion to various members.

The total content of silanol groups and alkoxysilyl groups in component (A) is determined by measuring the ²⁹ Si-NMR spectrum, the peak area of Si atoms bonded to the OH groups and OR groups, and the OH groups and OR groups. It can be calculated from the ratio of peak areas of Si atoms that are not bonded.

<Synthesis or Obtaining Method of (A) Component>
The method for synthesizing or obtaining the polysiloxane compound (A) is not particularly limited. As an example of the method for producing the polysiloxane compound (A), the polysiloxane compound [1] is an alkoxysilane compound represented by the following formula [3] (hereinafter referred to as “alkoxysilane compound [3]”). And at least one of them may be hydrolyzed and subjected to a polycondensation reaction.

R ¹ in the formula [3] has the same meaning as R ¹ in the formula [1], when R ¹ there are a plurality, R ¹ may be the same or different types from each other. R ² in the formula [3] is each independently a linear alkyl group having 1 to 4 carbon atoms or a branched alkyl group having 3 to 4 carbon atoms, and when a plurality of R ² are present, R ^{2 2} may be the same or different types. Y in Formula [3] is an integer of 1-3.

Examples of the linear alkyl group having 1 to 4 carbon atoms or the branched alkyl group having 3 to 4 carbon atoms in R ² of the formula [3] include a methyl group, an ethyl group, a propyl group, a butyl group, an isopropyl group, An isobutyl group, a sec-butyl group, and a tert-butyl group are mentioned. Of these, a methyl group and an ethyl group are preferable.

The alkoxysilane compound [3] is a trialkoxysilane compound (R ¹ Si (OR ² ) ₃ ) or a dialkoxysilane compound ((R ¹ ) ₂ Si (OR ² ) depending on the number of Y in the formula [3]. ₂ ) and monoalkoxysilane compounds ((R ¹ ) ₃ SiOR ² ). These may be used individually by 1 type and may use 2 or more types together by arbitrary ratios.

Specific examples of the trialkoxysilane compound include the following compounds, but are not limited thereto.
Methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, methyltriisopropoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltripropoxysilane, ethyltriisopropoxysilane, propyltrimethoxysilane, propyltriethoxy Silane, propyltripropoxysilane, propyltriisopropoxysilane, isopropyltrimethoxysilane, isopropyltriethoxysilane, isopropyltripropoxysilane, isopropyltriisopropoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltripropoxysilane, phenyl Triisopropoxysilane, trifluoromethyltrimethoxysilane, trifluoromethyltriethoxy Silane, pentafluoroethyltrimethoxysilane, pentafluoroethyltriethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, 3,3,3-trifluoropropyltriethoxysilane, 3-glycidoxypropyltrimethoxy Silane, 3-glycidoxypropyltriethoxysilane, [2- (3,4-epoxycyclohexyl) ethyl] trimethoxysilane, [2- (3,4-epoxycyclohexyl) ethyl] triethoxysilane, 3- (methacryloyl) Oxy) propyltrimethoxysilane, 3- (methacryloyloxy) propyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, trimethoxysilane, triethoxysilane.

Among these, preferred compounds include methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, trifluoromethyltrimethoxysilane, and trifluoromethyltriethoxysilane. Can be illustrated,
Examples of particularly preferable compounds include methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, and phenyltriethoxysilane.

Specific examples of the dialkoxysilane compound include the following compounds, but are not limited thereto.
Dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyldipropoxysilane, dimethyldiisopropoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, diethyldipropoxysilane, diethyldiisopropoxysilane, dipropyldimethoxysilane, dipropyldiethoxysilane , Diisopropyldimethoxysilane, diisopropyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, diphenyldipropoxysilane, diphenyldiisopropoxysilane, methylphenyldimethoxysilane, methylphenyldiethoxysilane, bis (trifluoromethyl) dimethoxysilane, Bis (trifluoromethyl) diethoxysilane, bis (3,3,3-trifluoropropyl) dimethoxy Run, bis (3,3,3-trifluoropropyl) diethoxysilane, methyl (3,3,3-trifluoropropyl) dimethoxysilane, methyl (3,3,3-trifluoropropyl) diethoxysilane.
Among these, preferred compounds include dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, methylphenyldimethoxysilane, methylphenyldiethoxysilane, bis (trifluoromethyl). ) Dimethoxysilane, bis (trifluoromethyl) diethoxysilane,
Examples of particularly preferred compounds include dimethyldimethoxysilane and dimethyldiethoxysilane.

Specific examples of the monoalkoxysilane compound include, but are not limited to, the following compounds.
Trimethylmethoxysilane, trimethylethoxysilane, trimethylpropoxysilane, trimethylisopropoxysilane, triethylmethoxysilane, triethylethoxysilane, triethylpropoxysilane, triethylisopropoxysilane, triphenylmethoxysilane, triphenylethoxysilane, triphenylpropoxysilane, tri Phenylisopropoxysilane, tris (trifluoromethyl) methoxysilane, tris (trifluoromethyl) ethoxysilane.

In a method in which at least one of the alkoxysilane compounds [3] is hydrolyzed and subjected to a polycondensation reaction, it may be referred to as an alkoxysilane compound represented by the following formula [4] (hereinafter referred to as “alkoxysilane compound [4]”). ) May be used in combination. It is preferable to use at least one of the alkoxysilane compounds [4] in view of further improving the heat resistance of the resulting resin plate, metal-clad laminate, etc. and easily exhibiting good adhesion to various members.

^{R 2} in the formula [4] has the same meaning as ^{R 2} in the formula [3].

  Specific examples of the alkoxysilane compound [4] include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, and tetraisopropoxysilane.

  A method for hydrolyzing and polycondensing at least one of the alkoxysilane compounds [3] will be specifically described. First, after a predetermined amount of the alkoxysilane compound [3] is collected in a reaction vessel at room temperature (in particular, an atmospheric temperature not heated or cooled, usually about 15 ° C. or higher and about 30 ° C. or lower; the same applies hereinafter), Water for hydrolyzing the alkoxysilane compound, a catalyst for proceeding the polycondensation reaction, and optionally a reaction solvent are added to the reactor to form a reaction solution. At this time, the order in which the reaction materials are charged is not limited to this, and the reaction materials can be charged in any order. Moreover, when using together alkoxysilane compound [4], what is necessary is just to add in a reactor similarly to alkoxysilane compound [3]. Next, the polysiloxane compound [1] can be obtained by allowing hydrolysis and condensation reaction to proceed at a predetermined temperature for a predetermined time while stirring the reaction solution. At this time, in order to prevent the unreacted raw material alkoxysilane compound, water, reaction solvent and / or catalyst in the reaction system from being distilled out of the reaction system, the reaction vessel is closed or a condenser, etc. It is preferable to attach a reflux apparatus to reflux the reaction system.

  The amount of water used in the production of the polysiloxane compound [1] is not particularly limited. From the viewpoint of reaction efficiency, it is preferably 1 to 5 times in terms of a molar ratio with respect to the total number of moles of alkoxy groups contained in the alkoxysilane compound of the raw material compound. If it is 1 time or more, hydrolysis of the alkoxysilane compound is likely to proceed efficiently, and if it is 5 times or less, gelation or the like is difficult to occur and handling is difficult.

  In the production of the polysiloxane compound [1], the reaction can be carried out even under solvent-free conditions, but a reaction solvent can also be used. The type of the reaction solvent is not particularly limited as long as the reaction for producing the polysiloxane compound [1] is not inhibited. Among these, a water-soluble organic solvent is preferable, and an alcohol solvent is particularly preferable because the reaction proceeds at an appropriate reaction rate. Specifically, the alcohol solvent is methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, t-butyl alcohol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono- Examples include n-propyl ether, propylene glycol mono-n-butyl ether, propylene glycol mono-t-butyl ether, 3-methoxy-1-butanol, 3-methyl-3-methoxy-1-butanol, etc. It is not limited to. The amount of the reaction solvent used is preferably 1.0 times or less in terms of a molar ratio to the amount of water used. Further, the condensation reaction may be performed without using a reaction solvent. In this case, the alcohol generated by hydrolysis of the alkoxysilane compound serves as the above-mentioned reaction solvent.

  As the type of catalyst used in the production of the polysiloxane compound [1], an acid, a base, or a metal complex can be used. An acid catalyst is preferred because it is easy to control the total content of silanol groups and alkoxysilyl groups in the polysiloxane compound [1]. The type of the acid catalyst is not particularly limited, and specifically, acetic acid, propionic acid, trifluoroacetic acid, methanesulfonic acid, trifluoromethanesulfonic acid, formic acid, oxalic acid, maleic acid, camphorsulfonic acid, benzenesulfonic acid, Examples include tosylic acid, hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, boric acid and the like. Of these, acetic acid, hydrochloric acid, sulfuric acid, and nitric acid are preferable, and acetic acid is particularly preferable because the catalyst can be easily removed after the reaction. Moreover, the kind of base catalyst is not specifically limited. For example, 1,8-diazabicyclo [5.4.0] undecene-7, diethylamine, triethylamine, imidazole, pyridine, triphenylphosphine, sodium hydroxide, potassium hydroxide, lithium hydroxide, magnesium hydroxide, sodium carbonate, carbonic acid Examples include potassium, cesium carbonate, sodium hydrogen carbonate and the like. Moreover, the kind of metal complex catalyst is not specifically limited. For example, zinc octylate, zinc benzoate, zinc p-tert-butylbenzoate, zinc laurate, zinc stearate, aluminum chloride, aluminum perchlorate, aluminum phosphate, aluminum triisopropoxide, aluminum acetylacetonate, Aluminum butoxybisethyl acetoacetate, tetrabutyl titanate, tetraisopropyl titanate, tin octylate, tin naphthenate, cobalt naphthenate and the like can be exemplified.

The amount of the catalyst used in the production of the polysiloxane compound [1] is 1.0 × 10 ⁻⁵ times or more in terms of a molar ratio with respect to the total number of moles of alkoxy groups contained in the alkoxysilane compound of the raw material compound. It is preferably 0 × 10 ⁻¹ or less.

  The reaction time in the production of the polysiloxane compound [1] depends on the type of catalyst, but is usually about 3 hours to 48 hours, and the reaction temperature is usually room temperature to 180 ° C.

  After the reaction, it is preferable to separate and purify the polysiloxane compound [1] from the reaction system from the viewpoint of handling the polysiloxane compound [1]. This separation method is not particularly limited. For example, a method of extracting is mentioned. Specifically, after the temperature of the reaction solution after the reaction described above is lowered to room temperature, the polysiloxane compound [1] present in the reaction system is extracted by contacting with a non-aqueous organic solvent as an extraction solvent. The solution after this extraction may be washed with water or saline as necessary, and water contained in the solution may be removed using a desiccant. Finally, a high-purity polysiloxane compound [1] or polysiloxane compound [1] -containing solution can be obtained by removing the volatile components in the solution under reduced pressure. In addition, when the reaction solution after the reaction is separated into an aqueous layer and a layer containing the polysiloxane compound [1] at room temperature without adding an extraction solvent, the aqueous layer is removed without using the extraction solvent. Then, the polysiloxane compound [1] can be purified from the layer containing the polysiloxane compound [1].

  Examples of the non-aqueous organic solvent used as the extraction solvent include ether solvents, aromatic solvents, ester solvents, chlorine solvents, aliphatic solvents, alcohol solvents, and ketone solvents.

  Specific examples of the ether solvent include diethyl ether, diisopropyl ether, methyl t-butyl ether, and dibutyl ether. Specific examples of the aromatic solvent include benzene, toluene, and xylene. Specific examples of the ester solvent include ethyl acetate and butyl acetate. Specific examples of the chlorinated solvent include chloroform and dichloromethane. Specific examples of the aliphatic solvent include pentane, hexane, heptane, and cyclohexane. Specific examples of the alcohol solvent include 1-butanol and isobutyl alcohol. Specific examples of the ketone solvent include methyl isobutyl ketone. These may be used individually by 1 type and may use 2 or more types together by arbitrary ratios.

  The kind of said desiccant is not specifically limited, For example, solid desiccants, such as magnesium sulfate, sodium sulfate, calcium sulfate, a synthetic zeolite, can be used.

<(B) component: silica>
The component (B) is silica having a pH value of 6.1 or less at 25 ° C. of extracted water. In the siloxane resin composition used in the present invention, when the component (B) is contained, the gas generated at the time of heat-curing is smooth even though the component (A) is a condensed polysiloxane compound. It is discharged to the outside, and foaming when the prepreg is molded into a resin plate or a metal-clad laminate can be suppressed.

  In addition, in the silica whose surface is not chemically modified with a coupling agent or the like, it is known that the amount of silanol groups on the surface per unit volume increases as the pH value of extracted water at 25 ° C. decreases. Further, in silica having a pH value of 6.1 or less, the amount of silanol groups on the surface per unit volume is sufficiently large, and gas such as water or alcohol generated at the time of heat curing is good with silanol groups. In order to show affinity, the siloxane resin composition of the present invention is presumed that the gas generated at the time of heat curing is smoothly discharged to the outside of the system through the surface of the silica, and foaming of the cured product is suppressed.

(B) Extraction water of component means an eluate obtained as a result of stirring 10 g of component (B) as a sample with 200 mL of purified water at 80 ± 3 ° C. for 1 hour and then cooling to room temperature. The pH value of means that the pH value of the extracted water thus obtained is measured as follows.

The pH value of the extracted water of component (B) is measured according to the test method specified in JIS K 1150: 1994. Specifically, first, about 10 g of component (B) dried at about 170 ° C. in air for 2 hours is weighed to 2 digits below the decimal point. The component (B) is put into a 300 mL beaker, 200 mL of purified water is added, the beaker is covered with a watch glass, stirred at 80 ± 3 ° C. for 1 hour, cooled to room temperature, and a supernatant is collected. After the temperature of the supernatant is 25 ° C., the pH is measured using a pH meter, and the pH value is read to the first decimal place. The purified water has a conductivity of 1 × 10 ⁻³ S / m or less, the pH meter is of type II defined in JIS Z 8802, and the beaker is defined in JIS R 3505. Use a hard material.

Specific examples of the component (B) include crystalline silica, natural fused silica, synthetic fused silica, deflagration silica, fumed silica, sol-gel silica, flame silica, and precipitation silica. 1 type may be used independently and 2 or more types may be used together in arbitrary ratios. Among these, natural fused silica, synthetic fused silica, and deflagration silica are preferred from the viewpoint that the siloxane resin composition of the present invention has excellent flowability at room temperature or heating, that is, moldability. Two or more kinds may be used together in any ratio, and other kinds of silica can be added and used in any ratio with respect to natural fused silica, synthetic fused silica, and deflagration silica. Specific examples of preferred combinations include natural fused silica and deflagration silica, synthetic fused silica and deflagration silica, but are not limited to these combinations.

[Natural fused silica]
The natural fused silica is a general term for spherical silica produced by melting natural silica at a high temperature, and commercially available natural fused silica can be used. Specific examples include FB series manufactured by Denki Kagaku Kogyo Co., Ltd., Fuse Rex series manufactured by Tatsumori Co., Ltd., MSV series, MSR series, HS series manufactured by Nippon Steel & Sumikin Materials Co., Ltd., and the like. Specific examples of the FB series manufactured by Denki Kagaku Kogyo Co., Ltd. include, but are not limited to, natural fused silica having the following trade names.
FB-5D, FB-12D, FB-20D, FB-105, FB-940, FB-9454, FB-950, FB-105FC, FB-870FC, FB-875FC, FB-9454FC, FB-950FC, FB- 300FC, FB-105FD, FB-970FD, FB-975FD, FB-950FD, FB-300FD, FB-400FD, FB-7SDC, FB-5SDC, FB-3SDC, FB-40S, FB-570, FB-820.
Specific examples of the MSR series manufactured by Tatsumori include, but are not limited to, natural fused silica having the following trade names.
MSR-LV24, MSR-5100.

[Synthetic fused silica]
The synthetic fused silica is a general term for spherical silica produced by a melting reaction of silicon tetrachloride or the like, and commercially available synthetic fused silica can be used. Specific examples include Excelica series manufactured by Tokuyama Corporation and EMIX series manufactured by Tatsumori Corporation. Specific examples of the Excelica series manufactured by Tokuyama Corporation include, but are not limited to, synthetic fused silica having the following trade names.
SE-8, SE-15, SE-30, SE-40, SE-15K, SE-30K, UF-305, UF-310, UF-320, UF-345, UF-725, ML-902SK.
Specific examples of the EMIX series manufactured by Tatsumori Co., Ltd. include, but are not limited to, synthetic fused silica having the following trade names.
EMIX-CER.

[Deflagration Silica]
The deflagration method silica is a general term for spherical silica produced by an oxidation reaction of silicon powder, and commercially available deflagration method silica can be used. Specifically, Admafine Co., Ltd. Admafine SO series, Tatsumori Co., Ltd. XR series, etc. are mentioned. Specific examples of Admafine SO series manufactured by Admatechs, Inc. include, but are not limited to, deflagration method silica having the following trade names.
SO-C1, SO-C2, SO-C4, SO-C5, SO-C6.
Specific examples of the XR series manufactured by Tatsumori Co., Ltd. include, but are not limited to, deflagration silica with the following trade names.
XR-08P, XR-15P.

[Component (B): Shape of silica]
The shape of the component (B) in the present invention is not particularly limited. Usually, a crushed shape, a spherical shape, a plate shape, a bead shape, etc. are mentioned. Especially, since the moldability of a siloxane resin composition is excellent, spherical shape is preferable. Moreover, (B) component which added the silica of another shape in arbitrary ratios with respect to spherical silica can also be used.

[(B) component: silica particle size]
The particle size distribution of the component (B) in the present invention is usually preferably such that the median diameter value, which is the particle size corresponding to the median value of the distribution by the laser diffraction particle size distribution measurement method, is 0.02 μm or more and 500 μm or less. More preferably, it is 0.05 μm or more and 100 μm or less. The value of the maximum particle size contained in the component (B) is preferably 750 μm or less, and more preferably 150 μm or less. The value of the minimum particle diameter contained in the component (B) is not particularly limited.

  Here, the particle diameter of the component (B) is determined by a laser diffraction particle size distribution measuring device. Although the equipment to be used is not particularly limited, Nikkiso Co., Ltd. Microtrack, Horiba Ltd. LA, Cirrus CILAS, Malvern Mastersizer, Beckman Coulter LS, etc. can be used. The median diameter in the laser diffraction particle size distribution measurement method is also commonly referred to as d50. When the powder is divided into two parts from a certain particle diameter, the volume on the large side and the small side is equivalent. It is.

  In addition, the particle diameters of the natural fused silica and the synthetic fused silica are generally 1 μm or more and 100 μm or less, and are within the median diameter range. The particle size of the deflagration silica is generally 0.1 μm or more and 3 μm or less, and is within the median diameter range.

  As the particle diameter of the component (B) according to the present invention is smaller, that is, the specific surface area is larger, the amount of silanol groups on the surface of the component (B) per unit volume increases. If this amount increases, the effect of suppressing foaming when the prepreg is molded into a resin plate, a metal laminate, or the like tends to increase. Therefore, even if the ratio of the component (B) to the total amount of the components (A) and (B) is small, a resin plate or a metal-clad laminate without foaming can be obtained. However, the smaller the particle size of the component (B), the lower the fluidity of the siloxane resin composition used in the present invention at room temperature or during heating, and the moldability tends to decrease. For this reason, the particle diameter of the component (B) is preferably within the above range.

  The component (B) in the present invention may exhibit a plurality of frequency peaks in the particle size distribution measurement. In particular, when the prepreg of the present invention is molded by a compression molding method, the component (B) is a compound in which particles having greatly different particle diameters are blended in a ratio that facilitates a close-packed structure (hereinafter referred to as “close-packed”). It is preferably referred to as “filling type (B) component”. For example, in addition to the large particle size (B) component, the medium particle size or the small particle size or both of the (B) component are blended at a predetermined ratio, so that the gap between the large particle size (B) component is medium. Filling with the component (B) of the particle size or the small particle size or both results in the closest packed state. By using the close-packed component (B), the siloxane resin composition contained in the prepreg is greatly improved in fluidity during heating, and compression molding becomes easy. In addition, by using the close-packed type (B) component, the filling rate is increased, and the mechanical strength and electrical properties of the resin plate and metal-clad laminate of the present invention can be improved. The particle size distribution by the laser diffraction particle size distribution measurement method of the close-packed (B) component is, for example, 10 μm or more and 100 μm or less and 1 μm or more and 10 μm or less, each having two frequency peaks, 10 μm or more Examples include one having a total of three frequency peaks, one for each of 100 μm or less, 1 μm or more and 10 μm or less, and 0.1 μm or more and 1 μm or less.

  As the close-packed type (B) component in the present invention, specifically, FB-940, FB-570, FB-820 manufactured by Denki Kagaku Kogyo Co., Ltd., Excelica ML-902SK manufactured by Tokuyama Co., Ltd., and Tatsumori Co., Ltd. Examples thereof include, but are not limited to, MSR-LV24, MSR-5100, EMIX-CER, and the like. Moreover, two or more different (B) components can be mixed to prepare a close-packed (B) component.

  The component (B) in the present invention may be one containing particles having a particle size of 3 μm or less (hereinafter sometimes referred to as “microparticle-containing type (B) component”). By using the component (B) containing fine particles, the condensation reaction of the silanol group and the alkoxysilyl group in the component (A) is accelerated during the heating of the siloxane resin composition, and the composition is cured accordingly. The speed can be greatly improved. This is particularly effective when molding a prepreg by the compression molding method, and the effects of lowering the molding temperature, shortening the molding time, and improving the releasability can be obtained. Productivity and surface smoothness of laminated plates and the like are improved.

  The proportion of particles having a particle size of 3 μm or less in the fine particle-containing type (B) component in the present invention is preferably 1% by mass or more and 50% by mass or less, and more preferably 12% by mass or more and 45% by mass or less. It is particularly preferred. When the amount is less than 1% by mass, the above-described effect of improving the curing rate may not be obtained. When the amount exceeds 50% by mass, the fluidity and moldability of the siloxane resin composition may be deteriorated.

  The kind of particle | grains with a particle diameter of 3 micrometers or less in the microparticle containing type | mold (B) component in this invention is not specifically limited. Specific examples include deflagration silica, fumed silica, sol-gel silica, and flame silica. Of these, deflagration silica is preferred from the viewpoint that the siloxane resin composition of the present invention has excellent flowability at room temperature or heating, that is, moldability. Examples of the deflagration method silica include Admafine Corporation's Admafine SO series and Tatsumori Corporation's XR series.

  When the prepreg of the present invention is molded by a compression molding method, the component (B) is more preferably a close-packed type (B) component and a fine particle-containing type (B) component. By using such a component (B), it is possible to simultaneously improve the fluidity and the curing rate during heating. Specific examples of such component (B) include Exelica ML-902SK manufactured by Tokuyama Co., Ltd. and Admafine SO Series manufactured by Admatechs Co., Ltd. The ratio of Admafine SO Series to the total amount of both is 1% by mass or more and 50% by mass. Although what was mix | blended so that it might become in the range of% or less is mentioned, it is not limited to these.

It is preferable that the surface of the component (B) is not chemically modified with a coupling agent or the like and the surface silanol groups are exposed. Of course, silica particles whose surfaces are chemically modified can be used as long as the effects of the present invention are not impaired.

  In the siloxane resin composition used in the present invention, the ratio of the component (B) to the total amount of the component (A) and the component (B) is within the range of 70% by mass to 97% by mass. It is blended as follows. When the proportion of the component (B) is less than 70% by mass, the resulting resin plate or metal-clad laminate may foam, and when it exceeds 97% by mass, a bulk or thin film cured product may be obtained. It becomes difficult. If it is in the range of 70% by mass or more and 97% by mass or less, foaming in the resulting resin plate or metal-clad laminate can be suppressed, and a bulk or thin film cured product can be obtained.

<Other ingredients>
For the purpose of adjusting the physical properties of prepregs, prepreg molded bodies, resin plates, and metal-clad laminates, siloxane resin compositions include inorganic fillers and heat resistant resins in addition to components (A) and (B). Further, additives such as a release agent, a pigment, a flame retardant, a curing catalyst, a latent curing accelerator, and an antiblocking agent may be further contained. These additives may contain 1 type independently, and may contain 2 or more types in arbitrary ratios. The amount in the case of containing these additives is not particularly limited as long as it is an effective amount as various additives as long as the characteristics of the prepreg of the present invention, such as foam suppression properties, are not impaired. It is preferable that the ratio with these all additives is 5 mass% or less with respect to the total amount of (A) component and (B) component.

[Inorganic filler]
Specific examples of the inorganic filler include silica, alumina, titania, zirconia, clay minerals such as talc and kaolin, glass, zinc oxide, boron nitride, aluminum nitride, calcium carbonate, magnesium carbonate that are not in the category of component (B). And carbon allotropes such as zirconium phosphate, zirconium phosphate tungstate, diamond and carbon nanotubes. These may be used individually by 1 type and may use 2 or more types together. The shape of the inorganic filler is not particularly limited, and examples thereof include a crushed shape, a spherical shape, a plate shape, a bead shape, a rod shape, a fiber shape, a needle shape, and a hollow shape.

[Heat resistant resin]
Specific examples of the heat resistant resin include nanocellulose, aramid fiber, carbon fiber, PEEK resin, and polyimide. These may be used individually by 1 type and may use 2 or more types together. The shape of the heat resistant resin is not particularly limited, and examples thereof include a crushed shape, a spherical shape, a plate shape, a bead shape, a rod shape, a fiber shape, a needle shape, and a hollow shape.

[Release agent]
Specific examples of the release agent include candelilla wax, carnauba wax, rice wax, montan wax, paraffin wax, synthetic wax, tetrafluoroethylene resin, tetrafluoroethylene / perfluoroalkoxyethylene copolymer resin, four Examples thereof include ethylene fluoride / hexafluoropropylene copolymer resin, ethylene tetrafluoride / ethylene copolymer resin, vinylidene fluoride resin, dimethyl silicone, and silicone fluoride. These may be used individually by 1 type and may use 2 or more types together.

[Pigment]
Specific examples of the pigment include carbon black, zinc white, lead white, lithopone, titanium dioxide, precipitated barium sulfate, barite powder, red lead, iron oxide red, chrome yellow, zinc yellow, ultramarine blue, prussian blue. And phthalocyanines, polycyclic pigments, azo pigments, and the like. These may be used individually by 1 type and may use 2 or more types together.

[Flame retardants]
Specific examples of the flame retardant include a halogen flame retardant, a phosphorus flame retardant, a metal hydroxide flame retardant, and an antimony flame retardant. These may be used individually by 1 type and may use 2 or more types together.

[Curing catalyst]
As a curing catalyst, the thing similar to what was mentioned as a kind of catalyst used in manufacture of the above-mentioned (A) component is mentioned. By adding a curing catalyst, the curing rate of the siloxane resin composition used in the present invention can be adjusted.

[Latent curing accelerator]
Specifically, as the latent curing accelerator, a thermal acid generation type latent curing accelerator, a Lewis acid-organic compound complex type latent curing accelerator, an inclusion compound type latent curing accelerator, a microcapsule type latency Examples thereof include a curing accelerator, an amine salt-type latent curing accelerator, and a phosphine salt-type latent curing accelerator. These may be used individually by 1 type and may use 2 or more types together by arbitrary ratios.

  The siloxane resin composition used in the present invention for the purpose of adjusting the dispersibility of the above-mentioned inorganic filler, heat-resistant resin, release agent, pigment, flame retardant, curing catalyst, latent curing accelerator and the like. May further contain a coupling agent. Such coupling agents include methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, ethyltrimethoxysilane, propyltrimethoxysilane, isopropyltrimethoxysilane, trifluoromethyltrimethoxysilane. , Pentafluoroethyltrimethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, vinyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane 3-methacryloxypropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, tris- (trimethoxysilylpropyl) isocyanurate or 3-isocyanatopropyltri Tokishishiran, and the like. The amount in the case of containing such a coupling agent is not particularly limited as long as it is an effective amount as a coupling agent as long as it does not impair characteristics such as the foam suppressing property of the prepreg of the present invention. It is preferable that the ratio of the coupling agent is 2% by mass or less with respect to the total amount of the component (A) and the component (B).

<Preparation of siloxane resin composition>
The siloxane resin composition used in the present invention can be prepared by blending the (A) component, the (B) component, and other additives as necessary. The amount of each component is as described above. Each component is preferably dispersed uniformly, and at least the component (B) is preferably dispersed without being aggregated in the component (A). If the dispersibility of the component (B) in the component (A) is good, the resin plate or metal-clad laminate of the present invention exhibits good adhesion and mechanical strength.

  The method for uniformly dispersing each component is not particularly limited. Usually, each component can be uniformly dispersed by collecting each component in a kneading vessel and kneading at room temperature or while heating. The charging procedure of each component is not particularly limited. First, all components may be collected in a kneading container and kneaded, or each component may be collected in an arbitrary order and kneaded in stages. When two or more different types of component (A) and / or (B) are used, they may be mixed in advance and then charged into the kneading container, or may be charged separately into the kneading container. Good. As a method of mixing two or more types of component (A) in advance, a mixing device such as a magnetic stirrer, mechanical stirrer, mixer, planetary mixer, stirring and defoaming device, static mixer, double-arm kneader, or pressure kneader is used. A method is mentioned. As a method of mixing two or more kinds of components (B) in advance, shake in a closed container, or mechanical stirrer, mixer, planetary mixer, Spartan mixer, stirring deaerator, high-speed fluid mixer, container rotating mixer , A method using a mixing device such as a V-type mixer, a W-type mixer, a double-arm kneader, or a pressure-type kneader.

  In one embodiment of the preparation of the siloxane resin composition, when two or more different (B) components are used and (A) component and the (B) component are at least kneaded to obtain the composition, (B) You may use what mixed the component. A prepreg exhibiting good moldability can be efficiently obtained from the siloxane resin composition of the present invention prepared using the component (B) mixed in advance. This may be due to the fact that the component (B) may agglomerate depending on the type, shape, and particle size of the component (B).

  In one embodiment of the preparation of the siloxane resin composition, when two or more different types of the component (B) are used, one or more types of the component (B) and the component (A) are kneaded, and then another 1 You may add and knead | mix the (B) component more than a seed | species.

  In one embodiment of the preparation of the siloxane resin composition, when three or more different types of (B) component are used, two or more types of (B) component and (A) component mixed in advance are kneaded, and then Alternatively, one or more other components (B) may be added and kneaded.

  The method for kneading the siloxane resin composition is not particularly limited. Specifically, a method of mixing by hand using a spatula, a mortar or the like, or using a kneading apparatus can be mentioned. Specific examples of the kneader include a pulverizer, a two-roll mill, a three-roll mill, a kneedex, a high-speed fluidized mixer, a planetary mixer, a double-arm kneader, a pressure-type kneader, or a continuous kneader. it can. Among them, since a siloxane resin composition having particularly excellent dispersibility of each component can be obtained, it is preferable to knead using a double-arm kneader, a pressure kneader, or a continuous kneader.

  When the siloxane resin composition is kneaded with a kneading apparatus, the kneading temperature is preferably from room temperature to 250 ° C. The time for the kneading operation is not particularly limited. Moreover, you may carry out, distribute | circulating pressure reduction or inert gas.

  When the siloxane resin composition is kneaded, as a pretreatment, an operation of previously homogenizing each component to some extent using a mixing apparatus, so-called preliminary kneading, may be performed, and then kneading may be performed. Specific examples of the mixing device for the preliminary kneading include a mechanical stirrer, a mixer, a planetary mixer, a high-speed fluidized mixer, a stirring deaerator, and a crusher. The preliminary kneading may be performed on the total amount of each component or only a part thereof. Of course, only the kneading operation may be performed without pre-kneading.

  The siloxane resin composition may be subjected to a partial condensation reaction of the component (A) in the composition by heat treatment (hereinafter sometimes referred to as “B-stage”). This B-stage makes it possible to adjust the fluidity at room temperature or during heating according to the molding method while increasing the curing rate of the siloxane resin composition. The B-stage of the siloxane resin composition can be performed by kneading each component and then allowing it to stand in an oven set at an arbitrary temperature. Alternatively, by performing kneading of each component while heating, B-stage can be performed simultaneously with the kneading. Alternatively, a B-staged siloxane resin composition can also be obtained by a method in which only the component (A) is heat-treated before kneading and then kneaded with other components.

  In the B-stage formation of the siloxane resin composition, the temperature of the heat treatment is preferably 50 ° C. or higher and 250 ° C. or lower. The time for the heat treatment in the B stage is not particularly limited. Moreover, you may carry out, distribute | circulating pressure reduction or inert gas.

[Prepreg]
A prepreg is a semi-cured composite material prepared by impregnating an organic resin into a fiber substrate such as glass cloth, carbon nanofiber, or cellulose nanofiber and drying it.

  The prepreg of the present invention is a prepreg comprising a fiber base material and a siloxane resin composition, wherein the siloxane resin composition contains at least the components (A) to (B), and the components (A) and (B) The ratio of the component (B) to the total amount of prepreg is 70% by mass or more and 97% by mass or less. A fiber base material is impregnated with a siloxane resin composition containing a predetermined amount of the components (A) to (B) dissolved and dispersed in a solvent, and then the fiber base material is dried to evaporate the solvent. By removing the prepreg, a prepreg can be produced. Impregnation is performed by dipping or coating. The impregnation can be repeated a plurality of times as necessary. At this time, it is also possible to repeat the impregnation using solutions or dispersions of a plurality of siloxane resin compositions having different compositions and concentrations, and finally adjust to a desired composition and resin amount. The temperature at the time of drying is not particularly limited as long as it can evaporate the solvent, but is preferably 50 ° C. or higher and 150 ° C. or lower, more preferably 60 ° C. or higher and 120 ° C. or lower. The content of the siloxane resin composition in the prepreg is usually 20% by mass or more and 80% by mass or less, preferably 30% by mass or more and 60% by mass or less, with respect to the total amount of the fiber base material and the siloxane resin composition.

[Fiber base]
The fiber base material is prepared by knitting fibers or the like to adjust various shapes. The fiber base material in the present invention is impregnated with the siloxane resin composition to be a material for producing a prepreg. Examples of the fibers include inorganic fibers, organic fibers, and combinations of inorganic fibers and organic fibers. Examples of the inorganic fiber include glass fiber, quartz fiber, alumina fiber, silicon carbide fiber, carbon fiber, carbon nanofiber, and metal fiber. Examples of the organic fiber include polyamide resin fiber, polyester resin fiber, polyimide resin fiber, fluororesin fiber, cellulose fiber, and cellulose nanofiber. Examples of the substrate include fine cloth and non-woven cloth. As a fiber base material, what combined the said fiber and the said base material suitably can be used. The shape of the fiber base material may be a cloth shape or a plate shape, and the thickness of the fiber base material can generally be, for example, 10 μm or more and 300 μm or less.

  Examples of the glass fiber substrate formed from glass fibers include glass cloth (glass fiber cloth) and glass non-woven cloth. The glass cloth is woven by twisting and spinning glass fibers into warp and weft yarns. As the glass cloth, for example, E glass cloth, NE glass cloth, D glass cloth, T glass cloth, Q glass cloth, quartz glass cloth and the like can be used. In addition, it is preferable to use a glass fiber substrate because it is easy to obtain a molded body, a resin plate, and a metal-clad laminate having excellent mechanical strength.

[solvent]
The solvent is not particularly limited as long as it can dissolve and disperse the siloxane resin composition and can be evaporated at a temperature at which the siloxane resin composition is maintained in an uncured or semi-cured state. For example, a solvent having a boiling point of 50 ° C. or higher and 200 ° C. or lower, preferably 80 ° C. or higher and 150 ° C. or lower is used. Specific examples of the solvent include hydrocarbon nonpolar solvents and ethers. Examples of the hydrocarbon nonpolar solvent include toluene, xylene, hexane, heptane and the like. Examples of ethers include dimethyl ether, diethyl ether, and isopropyl ether. The amount of the solvent used is not particularly limited as long as the siloxane resin composition is dissolved and dispersed, and the obtained solution or dispersion can be impregnated into the fiber substrate. It is usually 10 parts by mass or more and 200 parts by mass or less, preferably 20 parts by mass or more and 100 parts by mass or less with respect to parts by mass.

[Molded body, resin plate]
The molded object of this invention is the said prepreg or its laminated body, and a molded object. The prepreg laminate refers to a laminate of a plurality of prepregs. The shape of the molded body is not particularly limited, and may be a plate shape, a sheet shape, a tape shape, a film shape, a tubular shape, and the like, and the size and thickness are not particularly limited, and a partially convex shape, a concave shape or It may have a step shape. When the molded body of the present invention is used for producing the metal-clad laminate of the present invention described later and the printed wiring board of the present invention, it is referred to as a plate-shaped molded body (referred to as the resin plate of the present invention. The same is preferable), and the resin plate of the present invention may have a convex shape, a concave shape or a stepped shape in part.

As one aspect of the method for producing a molded article of the present invention, a fiber substrate is impregnated with a siloxane resin composition containing a predetermined amount of the components (A) to (B) dissolved in a solvent, In addition, there is a production method in which the solvent is removed from the fiber substrate by evaporating to obtain a prepreg, and then a desired number of the obtained prepregs are molded, preferably heated and pressed.
Despite the fact that the siloxane resin composition used in the present invention contains a condensation-type polysiloxane compound as the component (A), the prepreg of the present invention can be formed into molded products having various shapes and sizes. No foaming occurs. Moreover, since the crosslinked structure is comprised only by the chemically stable siloxane bond, the molded object of this invention shows very high heat resistance. Therefore, even if the molded article of the present invention is exposed for a certain period of time at a high temperature of about 250 ° C., the weight reduction and the mechanical strength are not substantially reduced. Furthermore, since the silanol group, the alkoxysilyl group, or both remain partially in the molded article of the present invention, good adhesion to various members is exhibited.

  This curing temperature is not particularly limited as long as the curing reaction of the siloxane resin composition used in the present invention proceeds. Although heating may be performed at a constant temperature, the temperature may be changed in multiple steps or continuously as required. The lower limit of the curing temperature is not particularly limited, but is preferably 150 ° C. or higher, and the upper limit is not particularly limited, but is preferably 250 ° C. or lower. The curing time can be variously set, and is preferably 1 minute or longer and 10 hours or shorter, more preferably 10 minutes or longer and 3 hours or shorter. The pressure at the time of curing can be variously set as required, and is preferably 10 MPa or more and 70 MPa or less. In addition, it can also heat in a normal pressure, pressurization, or a pressure reduction state.

  In one embodiment of the method for producing a molded article of the present invention, a method for producing a molded article by transferring the prepreg of the present invention or a laminate of the prepreg to a mold and heating and pressing is exemplified. The type of heating and pressing method and the number of times of heating and pressing are not particularly limited, and for example, a stamping method such as a compression molding method or an autoclave molding can be used. A compression molding method capable of producing a (resin plate) is preferable. As an aspect of molding by the compression molding method, a desired number of prepregs of the present invention can be obtained at room temperature using a mold of any shape and material that can be pressed with the contents sandwiched therebetween. After pinching, the method of compressing while heating with a hot press machine is mentioned. The compression molding temperature is preferably 150 ° C. or higher and 250 ° C. or lower, the molding pressure is preferably 10 MPa or higher, and the holding time is preferably 10 minutes or longer and 2 hours or shorter.

  When the prepreg of the present invention or a laminate of the prepreg is molded by a compression molding method, a mold to which a release agent has been applied in advance may be used. Examples of the release agent include organic, fluorine, and silicone. Examples of the release agent include liquid, spray, lump, and tablet. Of course, you may shape | mold using the metal mold | die to which the mold release agent is not apply | coated.

[Molded body of curable resin composition]
As one aspect of the molded body, a molded body of a curable resin composition including the fiber base material manufactured without passing through the prepreg and the siloxane resin composition may be mentioned. In this case, a method for molding the curable resin composition containing the fiber base material and the siloxane resin composition is not particularly limited, and examples thereof include transfer molding, injection molding, and potting molding (liquid casting). . As an aspect of molding for obtaining a molded body by the transfer molding method, the curable resin composition preformed in a tablet shape of any size is put into a preheated transfer molding machine and attached. And a method of transferring to a mold of the shape and material by pressurization with a plunger.

[Metal-clad laminate]
The metal-clad laminate of the present invention is a metal-clad laminate comprising a resin layer made of the resin plate and a metal layer. A preferred embodiment of the metal layer includes a layer made of a metal foil. A preferred embodiment of the metal-clad laminate of the present invention includes a metal-clad laminate comprising the resin plate and metal foil on both sides or one side of the resin plate. The metal-clad laminate of the present invention can be used for production of the printed wiring board of the present invention described later, and can also be used for various other applications. As one aspect of the method for producing a metal-clad laminate of the present invention, a metal foil disposed on one or both sides of one or a plurality of the prepregs stacked, a pressure of 5 MPa or more and 50 MPa or less, 150 ° C. or more and 250 The method of manufacturing by heat-press molding using a vacuum press etc. in the temperature range below ° C is mentioned. When a plurality of the prepregs are stacked, a metal foil may be installed between the prepregs.

[Metal foil]
The metal foil is not particularly limited. For example, copper, copper alloy, aluminum, aluminum alloy, silver, silver alloy, gold, gold alloy, zinc, zinc alloy, nickel, nickel alloy, tin, tin Metal foils such as iron alloys, iron, iron alloys, etc. can be mentioned, and copper foils are preferably used electrically and economically. Although the thickness of metal foil is not specifically limited, Usually, 1 micrometer or more and 200 micrometers or less, Preferably they are 3 micrometers or more and 100 micrometers or less.

  The thickness of the resin plate and metal-clad laminate of the present invention may be appropriately selected according to the use of the resin plate and metal-clad laminate of the present invention, and is not particularly limited, but is usually 20 μm or more and 2,000 μm. Hereinafter, it is preferably 50 μm or more and 1,000 μm or less.

[Printed wiring board]
The printed wiring board of the present invention is a printed wiring board comprising the resin plate and a wiring pattern on both sides or one side of the resin plate. The other structure in the printed wiring board of this invention is not specifically limited, The conventionally well-known various components may be provided and the various process may be given. The printed wiring board of the present invention can be used as a component for fixing semiconductor elements (electronic components) such as LSIs, resistor elements, capacitors, inductors, etc., and connecting the semiconductor elements (electronic components) with wiring. This is not the case. The printed wiring board of the present invention is manufactured by forming a wiring pattern on one surface or both surfaces of the resin plate or the metal-clad laminate using a known method such as a subtractive method, an additive method, or a semi-additive method. be able to.

[Semiconductor device]
The semiconductor device of the present invention is a semiconductor device comprising the printed wiring board and a semiconductor element installed on the printed wiring board. Specific examples of the semiconductor element include an LSI, a resistance element, a capacitor, and an inductor. The other configuration of the semiconductor device of the present invention is not particularly limited, and a conventionally known semiconductor device member may be provided in addition to the semiconductor element. Examples of such semiconductor device members include, for example, lead-out wiring, wire wiring, control elements, heat sinks, conductive members, die bonding materials, bonding pads, and the like.

  FIG. 1 is a cross-sectional view showing an example of a semiconductor device using the resin plate of the present invention. In the semiconductor mounting substrate shown in FIG. 1, a semiconductor element 1 is fabricated on a printed wiring board 4 of the present invention and connected by electrical connection terminals 3. The semiconductor element 1 and the electrical connection terminal 3 are sealed with a sealing resin 2.

  Examples of the electrical connection terminal 3 include a solder ball, and can be provided using a known method such as soldering. The sealing resin 2 can be provided by, for example, appropriately molding a known sealant such as a silicone sealant or an epoxy sealant into a desired shape and curing it. As the sealing resin 2, a siloxane resin composition used in the present invention may be appropriately molded into a desired shape and cured, and it is preferable to adopt from the viewpoint of heat resistance.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited by these Examples.

<Polysiloxane compound>
The physical properties of the polysiloxane compound synthesized in the following synthesis examples were evaluated by the following methods. [Quantification of total content of silanol groups and alkoxysilyl groups]
To 200 mg of the silicone resin, 0.5 mL of deuterated chloroform was added and dissolved, and 10 mg of chromium (III) acetylacetonate complex was added as a relaxation agent. The solution thus prepared was measured by ²⁹ Si-NMR. The detected signals were classified into peaks (a) to (h) as shown in Table 1, and the integrated value of each peak was calculated as a percentage (integral ratio) from the sum of all integrated values. For the ²⁹ Si-NMR measurement of the silicone resin, a nuclear magnetic resonance apparatus (manufactured by JEOL Ltd., model number: JNM-AL400) having a resonance frequency of 400 MHz was used. Here, each peak shown in Table 1 may overlap with a peak of an alkoxysilyl group that may be contained in the silicone resin. ^Since determination of silanol groups and alkoxysilyl groups is difficult in ²⁹ Si-NMR, all of the alkoxysilyl groups were regarded as silanol groups and quantified.

The HO—Si group content (mmol / g) was determined according to the following formula from the integration ratio calculated by the above method.
[A] = peak (a) integration ratio + 2 × peak (c) integration ratio + peak (d) integration ratio + 2 × peak (f) integration ratio + peak (g) integration ratio + 2 × peak (i) integration ratio + peak (J) integration ratio,
[B] = peak (a) integration ratio × 83.16 + peak (b) integration ratio × 74.15 + peak (c) integration ratio × 147.2 + peak (d) integration ratio × 138.2 + peak (e) integration ratio X 129.2 + peak (f) integration ratio x 85.13 + peak (g) integration ratio x 76.13 + peak (h) integration ratio x 67.12 + peak (i) integration ratio x 78.10 + peak (j) integration ratio × 69.09 + peak (k) integration ratio × 60.08,
HO—Si group content (mmol / g) = ([A] / [B]) × 1000.

[Mass average molecular weight (Mw) measurement]
The mass average molecular weights (Mw) of the various polysiloxane compounds synthesized were calculated by creating a calibration curve using polystyrene as a reference material by the gel permeation chromatography (abbreviation: GPC) method under the following conditions.
Device: manufactured by Tosoh Corporation, product name: HLC-8320GPC
Column: manufactured by Tosoh Corporation, trade name: TSK gel SuperHZ 2000x4, 3000x2
Eluent: Tetrahydrofuran

[Quantification of composition ratio of structural units]
Containing various polysiloxane compound synthesized is, the structure unit derived from the alkoxysilane compound is a starting compound was quantified its composition ratio by ^{1 H-NMR} or ^{29 Si-NMR. 1} H-NMR and ²⁹ Si-NMR were measured using a nuclear magnetic resonance apparatus (manufactured by JEOL Ltd., model number: JNM-AL400) having a resonance frequency of 400 MHz.

[Synthesis Example 1] Synthesis of polysiloxane compound (Aa) 240.40 g (1.000 mol) of phenyltriethoxysilane was added to a 2 L four-necked flask equipped with a stirring vane made of fluororesin and a Dimroth type reflux condenser. ), 148.30 g (1.000 mol) of dimethyldiethoxysilane was charged. Next, 239.64 g of isopropyl alcohol, 185.02 g of water, and 0.12 g of acetic acid were charged into the flask, and the flask was stirred while being heated to 100 ° C. to perform hydrolysis and condensation reaction. After 18 hours, the reaction solution was returned to room temperature, and 400 ml of diisopropyl ether and 400 ml of water were placed in the flask and stirred. Thereafter, the upper layer side of the reaction solution separated into two layers was collected and washed twice with 400 ml of water. Next, after removing a trace amount of water dissolved in diisopropyl ether with anhydrous magnesium sulfate, the anhydrous magnesium sulfate was filtered off. When diisopropyl ether was distilled off under reduced pressure using an evaporator, the desired polysiloxane compound (Aa) was obtained as a colorless viscous liquid. The yield is 182.57 g, the mass average molecular weight (Mw) is 828, the composition ratio is [PhSiO _3/2 ] _1.00 [Me ₂ SiO _2/2 ] _0.82 , and the total content of silanol groups and alkoxysilyl groups is It was 5.76 mmol / g.

[Synthesis Example 2] Synthesis of polysiloxane compound (Ab) 198.30 g (1.000 mol) of phenyltrimethoxysilane was added to a 1 L four-necked flask equipped with a stirring vane made of fluororesin and a Dimroth type reflux condenser. ) Prepared. Next, 144.00 g of isopropyl alcohol, 108.00 g of water, and 0.072 g of acetic acid were charged into the flask, and the flask was stirred while warming to 100 ° C. to perform hydrolysis and condensation reaction. After 6 hours, the reaction solution was returned to room temperature, and 200 ml of diisopropyl ether and 200 ml of saturated saline were placed in the flask and stirred. Thereafter, the upper layer side of the reaction solution separated into two layers was collected and washed twice with 200 ml of water. Next, after removing a trace amount of water dissolved in diisopropyl ether with anhydrous magnesium sulfate, the anhydrous magnesium sulfate was filtered off. When diisopropyl ether was distilled off under reduced pressure using an evaporator, the target polysiloxane compound (Ab) was obtained as a colorless solid. The yield was 135.10 g, the mass average molecular weight (Mw) was 943, the composition ratio was [PhSiO _3/2 ], and the total content of silanol groups and alkoxysilyl groups was 7.13 mmol / g.

[Synthesis Example 3] Synthesis of polysiloxane compound (Ac) 136.20 g (1.000 mol) of methyltrimethoxysilane was added to a 1 L four-necked flask equipped with a stirring blade made of fluororesin and a Dimroth type refluxing device. ) Prepared. Next, 144.00 g of isopropyl alcohol, 108.00 g of water, and 0.072 g of acetic acid were charged into the flask, and the flask was stirred while warming to 100 ° C. to perform hydrolysis and condensation reaction. After 6 hours, the reaction solution was returned to room temperature, and 200 ml of diisopropyl ether and 200 ml of water were placed in the flask and stirred. Thereafter, the upper layer side of the reaction solution separated into two layers was collected and washed twice with 200 ml of water. When diisopropyl ether was distilled off under reduced pressure using an evaporator, the desired polysiloxane compound (Ac) was obtained as a colorless viscous liquid. The yield was 19.66 g, Mw was 932, the composition ratio was [MeSiO _3/2 ], and the total content of silanol groups and alkoxysilyl groups was 12.5 mmol / g.

[Synthesis Example 4] Synthesis of polysiloxane compound (Ad) Into a 2 L three-necked flask equipped with a stirring vane made of fluororesin and a Dimroth type reflux condenser, 96.2 g (0.80 mol) of dimethyldimethoxysilane was added. Then, 158.6 g (0.80 mol) of phenyltrimethoxysilane and 52.1 g (0.25 mol) of tetraethoxysilane were charged. Next, 239.6 g of isopropyl alcohol, 185.0 g of water, and 0.12 g of acetic acid were charged into the flask, and the flask was stirred while being heated to 100 ° C. to perform hydrolysis and condensation reaction. After 6 hours, the reaction solution was returned to room temperature, and 400 ml of diisopropyl ether and 400 ml of water were placed in the flask and stirred. Thereafter, the upper layer side of the reaction solution separated into two layers was collected and washed twice with 400 ml of water. When diisopropyl ether was distilled off under reduced pressure using an evaporator, the desired polysiloxane compound (Ad) was obtained as a colorless viscous liquid. Yield: 143.4 g, Mw: 1,100, composition ratio: [PhSiO _3/2 ] _1.00 [Me ₂ SiO _2/2 ] _0.82 [SiO _4/2 ] _0.29 , silanol group and alkoxysilyl The total group content was 7.7 mmol / g.

[Synthesis Example 5] Synthesis of polysiloxane compound (A-e) 60.11 g (0.50 mol) of dimethyldimethoxysilane was added to a 2-liter three-necked flask equipped with a stirring blade made of fluororesin and a Dimroth-type reflux condenser. Then, 68.11 g (0.50 mol) of methyltrimethoxysilane was charged. Next, 120.0 g of isopropyl alcohol, 90.0 g of water, and 0.060 g of acetic acid were charged into the flask, and then the flask was stirred while being heated to 100 ° C. to perform hydrolysis and condensation reaction. After 6 hours, the reaction solution was returned to room temperature, and 200 ml of diisopropyl ether and 200 ml of water were placed in the flask and stirred. Thereafter, the upper layer side of the reaction solution separated into two layers was collected and washed twice with 200 ml of water. When diisopropyl ether was distilled off under reduced pressure using an evaporator, the desired polysiloxane compound (Ae) was obtained as a colorless viscous liquid. Yield is 55.0 g, Mw is 618, composition ratio is [MeSiO _3/2 ] _1.00 [Me ₂ SiO _2/2 ] _1.22 , and the total content of silanol groups and alkoxysilyl groups is 10.1 mmol / g Met.

[Synthesis Example 6] Synthesis of polysiloxane compound (A-f) 30.1 g (0.25 mol) of dimethyldimethoxysilane was added to a 3 L flask having a volume of 2 L equipped with a stirring blade made of fluororesin and a Dimroth type reflux condenser. Then, 102.17 g (0.75 mol) of methyltrimethoxysilane was charged. Next, 132.0 g of isopropyl alcohol, 99.0 g of water, and 0.066 g of acetic acid were charged into the flask, and then the flask was stirred while being heated to 100 ° C. to perform hydrolysis and condensation reaction. After 24 hours, the reaction solution was returned to room temperature, and 200 ml of diisopropyl ether and 200 ml of water were placed in the flask and stirred. Thereafter, the upper layer side of the reaction solution separated into two layers was collected and washed twice with 200 ml of water. When diisopropyl ether was distilled off under reduced pressure using an evaporator, the desired polysiloxane compound (Af) was obtained as a colorless viscous liquid. Yield is 64.8 g, Mw is 945, composition ratio is [MeSiO _3/2 ] _1.00 [Me ₂ SiO _2/2 ] _0.31 , and the total content of silanol groups and alkoxysilyl groups is 8.8 mmol / g. Met.

<Silica>
The physical properties of silica were evaluated by the methods shown below.

[Measurement of pH value of silica-extracted water]
The pH value of silica-extracted water at 25 ° C. was measured by a test method specified in JIS K 1150: 1994. 10.00 g of silica dried at 170 ° C. in air for 2 hours was taken, put in the following 300 mL beaker, and 200 mL of the following purified water was added. The beaker was covered with a watch glass, stirred at 80 ° C. for 1 hour, cooled to room temperature, and the supernatant was taken. After the liquid temperature of the obtained supernatant was 25 ° C., measurement was performed using the following pH meter, and the pH value was read to the first decimal place.
Beaker: Hard thing specified in JISR 3505 Purified water: Electric conductivity 1 × 10 ⁻³ S / m or less pH meter: HORIBA, Ltd., trade names: D-54 and 9681-10D, JIS Z
Of type II defined in 8802

Examples 1-24 and Comparative Examples 1-5
<Siloxane resin composition>
Polysiloxane compounds (Aa) to (Af) synthesized in Synthesis Examples 1 to 6, predetermined silica, and predetermined additives were collected in the proportions (parts by mass) described in Table 2 or Table 3. The siloxane resin compositions were prepared so as to be Examples 1 to 24 shown in Table 2 and Comparative Examples 1 to 5 shown in Table 3, respectively. In Tables 2 and 3, “-” means not added. In the preparation of the siloxane resin composition, each component such as a polysiloxane compound and silica was collected in a mortar and kneaded by kneading at room temperature until the properties by hand touch were constant. The total amount of each component was about 60 g.

<Preparation of prepreg>
About 60 g of the prepared siloxane resin composition was dissolved in toluene to prepare toluene dispersions (the concentration of the siloxane resin composition was adjusted so as to be a 30% by weight toluene dispersion). This toluene dispersion was impregnated (immersed) in a glass cloth (manufactured by Central Glass Fiber, product number EGW110TH-153, thickness 130 μm, density 18-19 pieces / 25 mm, 100 × 100 mm or 200 × 200 mm), and then 110 ° C. Toluene was evaporated by drying with hot air to prepare prepregs. The content of the siloxane resin composition in the obtained prepreg was about 50% by mass with respect to the total amount of the glass cloth and the siloxane resin composition.

<Production of resin plate>
The produced prepreg was compression molded at 160 ° C. and 40 MPa for 50 minutes using a hydraulic press machine (manufactured by Toho Press Mfg. Co., Ltd.). Next, resin plates were obtained by compression molding at 250 ° C. and 40 MPa for 1 hour, respectively.

<Evaluation of resin plate>
Foaming of the resin plates obtained in Examples 1 to 24 and Comparative Examples 1 to 5 was evaluated by the method shown below.

[Evaluation of foaming of resin plate]
The obtained resin plate was visually checked for foaming. In Tables 2 and 3, the case where foaming was not observed was described as “No”, and the case where foaming was observed was described as “Yes”.

[Heat resistance test of resin plate]
The resin plate obtained in Example 3 was heated at 250 ° C. until 2,000 hours passed, and the weight before and after the heating was measured to examine the weight change rate with respect to the heating time. As a result, the weight change rate of the resin plate was −0.30% by weight, and even after heating at 250 ° C. for 2,000 hours for a long time, the weight did not substantially decrease.

［シリカ］
SO-C2：爆燃法シリカ、メジアン径0.5μm、株式会社アドマテックス製
FB-20D：天然溶融シリカ、メジアン径23μm、電気化学工業株式会社製
ML-902SK：合成溶融シリカ、メジアン径24μm、株式会社トクヤマ製
SC2500-SQ：爆燃法シリカ、メジアン径0.5μm、株式会社アドマテックス製
SC5500-SQ：爆燃法シリカ、メジアン径1.5μm、株式会社アドマテックス製
SE-15K：合成溶融シリカ、メジアン径18μm、株式会社トクヤマ製
MSR-LV24：天然溶融シリカ、メジアン径23μm、株式会社龍森製
MSR-5100：天然溶融シリカ、メジアン径16μm、株式会社龍森製
EMIX-CER：合成溶融シリカ、メジアン径20μm、株式会社龍森製
混合シリカB-a：ML-902SK/ SO-C2 = 95/5（質量部）
［添加物］
♯30L：カーボンブラック、三菱化学株式会社製
CP-102：煙霧状シリカ、株式会社トクヤマ製

[silica]
SO-C2: Deflagration silica, median diameter 0.5μm, manufactured by Admatechs Co., Ltd.
FB-20D: Natural fused silica, median diameter 23μm, manufactured by Denki Kagaku Kogyo Co., Ltd.
ML-902SK: Synthetic fused silica, median diameter 24μm, manufactured by Tokuyama Corporation
SC2500-SQ: Deflagration silica, median diameter 0.5μm, manufactured by Admatechs Co., Ltd.
SC5500-SQ: deflagration silica, median diameter 1.5μm, manufactured by Admatechs Co., Ltd.
SE-15K: Synthetic fused silica, median diameter 18μm, manufactured by Tokuyama Corporation
MSR-LV24: Natural fused silica, median diameter 23μm, manufactured by Tatsumori Co., Ltd.
MSR-5100: Natural fused silica, median diameter 16μm, manufactured by Tatsumori Co., Ltd.
EMIX-CER: Synthetic fused silica, median diameter 20μm, Tatsumori Co., Ltd. mixed silica Ba: ML-902SK / SO-C2 = 95/5 (parts by mass)
[Additive]
# 30L: Carbon black, manufactured by Mitsubishi Chemical Corporation
CP-102: Smoke-like silica, manufactured by Tokuyama Corporation

  As shown in Comparative Example 1 in Table 3, when a resin plate was produced using only the polysiloxane compound (Aa), foaming occurred. In addition, foaming was observed in all of the resin plates of Comparative Examples 2 to 4 in Table 3, whereas no foaming was observed in the resin plates of the examples in Table 2. Further, as shown in Examples 4 to 5, 8 to 13, and 20, no foaming was observed in the resin plates obtained by molding a prepreg containing a siloxane resin composition to which a pigment was added as an additive. . Therefore, foaming does not occur when the prepreg in the category of the present invention is molded to form a resin plate.

  As shown in Examples 1 and 2 in Table 2 and Comparative Example 2 in Table 3, even if silica having the same pH value of the extracted water is used, foaming in the resin plate depends on the composition ratio of the polysiloxane compound and silica. There was a difference in the presence or absence of.

  On the other hand, as shown in Examples 1-2 in Table 2 and Comparative Examples 3-4 in Table 3, silica having a low pH value of the extracted water is used even if the composition ratio of the polysiloxane compound and silica is the same. Foam was not seen in the resin plate produced in this way, whereas foaming was seen in the resin plate produced using silica with a high pH value of the extracted water.

  As shown in Examples 1 to 24 in Table 2, the polysiloxane compound contained in the siloxane resin composition includes the siloxane resin composition even when polysiloxane compounds having different structural units and different composition ratios are used. No foaming was observed on the resin plate obtained by molding the prepreg.

  As shown in Table 3, a prepreg not included in the scope of the present invention described in Comparative Example 5 was molded. However, the resin plate could not be obtained after the heat treatment, and the resin was powdered.

DESCRIPTION OF SYMBOLS 1 ... Semiconductor element 2 ... Sealing resin 3 ... Electrical connection terminal 4 ... Printed wiring board

Claims (17)

A prepreg comprising a fiber substrate and a siloxane resin composition,
The siloxane resin composition is
(A) component: a polysiloxane compound containing at least two functional groups selected from the group consisting of a silanol group and an alkoxysilyl group in one molecule;
And (B) component: at least containing silica whose pH value of extracted water is 6.1 or less at 25 ° C., and the ratio of component (B) to the total amount of component (A) and component (B) is 70% by mass or more A prepreg that is 97% by mass or less. The prepreg according to claim 1, wherein the component (A) contains a polysiloxane compound having at least a structural unit represented by the following formula [1].

(In Formula [1], each R ¹ is independently a hydrogen atom, a linear alkyl group having 1 to 10 carbon atoms, a branched alkyl group having 3 to 10 carbon atoms, or a cyclic alkyl group having 3 to 10 carbon atoms. Group, a linear alkenyl group having 2 to 10 carbon atoms, a branched alkenyl group having 3 to 10 carbon atoms, a cyclic alkenyl group having 3 to 10 carbon atoms, or an aryl group having 5 to 10 carbon atoms, and Some or all of the hydrogen atoms in the alkyl group, alkenyl group, or aryl group may be substituted with halogen atoms, and some of the carbon atoms in the alkyl group, alkenyl group, or aryl group may be nitrogen atoms, oxygen atoms, and It may be substituted with at least one selected from the group consisting of silicon atoms, and the halogen atom is at least one selected from the group consisting of fluorine atoms, chlorine atoms, bromine atoms and iodine atoms A seed, in the case where R ¹ there are a plurality, R ¹ each oxygen atom of the same or different from each other a type may be. Formula [1] in an oxygen atom to form a siloxane bond, This represents an oxygen atom forming a silanol group or an alkoxysilyl group, wherein m and n in the formula [1] each represent an integer of 1 to 3, and m + n = 4 is satisfied. R ¹ represents a linear alkyl group having 1 to 10 carbon atoms, a branched alkyl group having 3 to 10 carbon atoms, a cyclic alkyl group having 3 to 10 carbon atoms, or an aryl group having 5 to 10 carbon atoms. The prepreg according to claim 2. The prepreg according to claim 2, wherein R ¹ represents a methyl group or a phenyl group. (A) A component contains the polysiloxane compound which has a structural unit represented by Formula [1], and a structural unit represented by following formula [2]. Prepreg.

(The oxygen atoms in the formula [2] each represent an oxygen atom forming a siloxane bond, or an oxygen atom forming a silanol group or an alkoxysilyl group.)   The prepreg according to any one of claims 1 to 5, wherein the total content of silanol groups and alkoxysilyl groups in the component (A) is 1 mmol / g or more and 15 mmol / g or less.   The prepreg according to any one of claims 1 to 6, wherein the component (B) contains silica particles having a particle diameter of 3 µm or less.   The prepreg as described in any one of Claims 1 thru | or 7 whose (B) component is a silica which shows a some frequency peak in a particle size distribution measurement.   The prepreg according to any one of claims 1 to 8, wherein the component (B) is silica whose surface is not chemically modified. A method for producing a prepreg comprising a fiber substrate and a siloxane resin composition,
(A) component: a polysiloxane compound containing at least two functional groups selected from the group consisting of a silanol group and an alkoxysilyl group in one molecule;
(B) component: the process of obtaining this siloxane resin composition by mixing at least the silica whose pH value of extraction water is 6.1 or less in 25 degreeC,
Impregnating and drying the siloxane resin composition on the fiber substrate,
The manufacturing method of a prepreg whose ratio of (B) component with respect to the total amount of (A) component and (B) component is 70 to 97 mass%. A method for producing a prepreg comprising a fiber substrate and a siloxane resin composition,
The siloxane resin composition is
(A) component: a polysiloxane compound containing at least two functional groups selected from the group consisting of a silanol group and an alkoxysilyl group in one molecule;
(B) component: Silica whose pH value of extraction water is 6.1 or less at 25 ° C.,
Including
The ratio of the component (B) to the total amount of the component (A) and the component (B) is 70% by mass or more and 97% by mass or less, and is a siloxane resin composition.
A method for producing a prepreg, comprising a step of impregnating the fiber substrate with the siloxane resin composition and drying. A molded body of the prepreg according to any one of claims 1 to 9 or a laminate of the prepreg. The resin board which consists of a molded object of Claim 12. A metal-clad laminate comprising a resin layer comprising the resin plate according to claim 13 and a metal layer. A metal-clad laminate comprising the resin plate according to claim 13 and a metal foil on both sides or one side of the resin plate. A printed wiring board comprising the resin board according to claim 13 and a wiring pattern on both sides or one side of the resin board. A semiconductor device comprising the printed wiring board according to claim 16 and a semiconductor element installed on the printed wiring board.

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