KR101929067B1 - Resin composition sheet, resin composition sheet with metal foil attached, metal base wiring board material, metal base wiring board, and led light source member - Google Patents

Abstract

The resin composition sheet of the present invention is formed of a resin composition containing a thermosetting resin, a phenol resin and an insulating inorganic filler, and the occupancy rate of the concave portion having a maximum depth of 0.5 mu m or more on the surface is 4% or less in area ratio.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition sheet, a resin composition sheet having a metal foil, a metal base wiring board material, a metal base wiring board, and an LED light source member. LED LIGHT SOURCE MEMBER}

The present invention relates to a resin composition sheet, a resin composition sheet having a metal foil, a metal base wiring board material, a metal base wiring board, and an LED light source member.

Background Art [0002] With the advancement of high-density and compact electronic devices, the amount of locally generated heat on a circuit or the like tends to increase, and a circuit board on which electronic components such as semiconductor devices are mounted is required to have high heat radiation performance. On the other hand, a high electrical insulation property as in the prior art is required.

For this reason, a resin composition having a high thermal conductivity and high electrical insulating properties has been put to practical use as a thermally conductive sealing material or a thermally conductive adhesive.

In connection with the above, Japanese Patent Application Laid-Open No. 2008-13759 discloses an epoxy resin composition containing an epoxy resin showing liquid crystallinity and an insulating inorganic filler, and has a high thermal conductivity and excellent processability.

However, in the epoxy resin composition described in Patent Document 1, sufficient electrical insulation can not be obtained in some cases.

The present invention provides a resin composition sheet capable of forming a resin cured product excellent in thermal conductivity and electrical insulation, a resin composition sheet having a metal foil, and a metal base wiring board material, a metal base wiring board, and an LED light source member formed using the resin composition sheet We will do it.

The present invention relates to the following.

≪ 1 > A thermosetting resin composition comprising a thermosetting resin, a phenol resin, and an insulating inorganic filler,

Wherein the occupancy rate of the concave portion having a maximum depth of 0.5 占 퐉 or more on the surface is 4% or less in area ratio.

<2> The resin composition sheet according to <1>, wherein a minimum melt viscosity at 20 ° C to 200 ° C is 10 Pa · s to 1000 Pa · s.

<3> The resin composition sheet according to <1> or <2>, wherein the insulating inorganic filler is contained in an amount of 40 vol% or more and 82 vol% or less.

<4> The method according to any one of <1> to <3>, wherein the insulating inorganic filler is at least one kind of filler selected from the group consisting of aluminum oxide, magnesium oxide, boron nitride, aluminum nitride, silicon nitride, silicon carbide, A resin composition sheet as set forth in any one of claims 1 to 4.

<5> The resin composition sheet according to any one of <1> to <4>, wherein the phenol resin has a structural unit represented by the following general formula (I).

[Chemical Formula 1]

In formula (I), R ¹ represents an alkyl group, an aryl group or an aralkyl group, R ² and R ³ each independently represent a hydrogen atom, an alkyl group, an aryl group or an aralkyl group, m represents an integer of 0 to 2 And n represents an integer of 1 to 10.

<6> A resin composition comprising the thermosetting resin, the phenol resin, and the resin composition containing the insulating inorganic filler,

Wherein the resin composition has a viscosity of 1000 mPa s to 10000 mPa 이하,

The resin composition sheet according to any one of <1> to <5>, wherein the resin composition sheet is formed by applying the resin composition onto a support substrate.

&Lt; 7 &gt; The thermoplastic resin composition according to any one of &lt; 1 &gt; to &lt;

Wherein the occupancy rate of the concave portion having a maximum depth of 0.5 占 퐉 or more on the surface is 4% or less in area ratio.

<8> The resin composition sheet according to any one of <1> to <7>, wherein the average thickness is 20 μm or more and 500 μm or less.

&Lt; 9 &gt; A resin composition sheet according to any one of &lt; 1 &gt; to &lt; 8 &gt;, and a metal foil having a metal foil.

&Lt; 10 &gt;

A metal substrate,

A metal base wiring board material having a thermally conductive insulating layer which is a cured product of the resin composition sheet according to any one of <1> to <8> is provided between the metal foil and the metal substrate.

&Lt; 11 &gt;

A metal substrate,

And a thermally conductive insulating layer which is a cured product of the resin composition sheet according to any one of <1> to <8> is provided between the wiring layer and the metal substrate.

<12> A resin composition sheet according to any one of <1> to <8>, a resin composition sheet having a metal foil according to <9>, a metal base wiring board material according to <10> &Lt; RTI ID = 0.0 &gt; 1, &lt; / RTI &gt;

According to the present invention, there is provided a resin composition sheet capable of forming a resin cured product excellent in thermal conductivity and electrical insulation, a resin composition sheet having a metal foil, and a metal base wiring board material, a metal base wiring board, and an LED light source member formed using the resin composition sheet can do.

1 shows a cross-sectional structure of an example of a metal base wiring board material of the present invention.
2 shows a cross-sectional structure of an example of a metal base wiring board of the present invention.
3 shows a cross-sectional structure of an LED light source member according to an embodiment of the present invention.

In the present invention, the term &quot; process &quot; means not only an independent process but also a case where the desired action of the process is achieved even if it can not be clearly distinguished from other processes.

In the present specification, the numerical range indicated by using &quot; ~ &quot; indicates a range including numerical values before and after &quot; ~ &quot; as the minimum value and the maximum value, respectively.

<Resin Composition Sheet>

The first resin composition sheet of the present invention is a resin composition sheet containing a thermosetting resin, a phenol resin, and an insulating inorganic filler, and the occupancy rate of the concave portion having a maximum depth of 0.5 탆 or more on the surface of the resin composition sheet is 4% .

The second resin composition sheet of the present invention has a lowest melt viscosity at 20 to 200 캜 of 10 to 1000 Pa s and a percentage of occupied area of recesses having a maximum depth of 0.5 탆 or more on the surface is 4% Sheet.

The recesses in the present invention are those present on the surface of the resin composition sheet in the B-stage state. More specifically, in the recesses in the present invention, the maximum depth of depressions present on the surface of the resin composition sheet in the B-stage state is 0.5 mu m or more from the surface of the resin composition sheet and less than the thickness of the resin composition sheet .

The resin composition sheet of the present invention is bonded to a metal foil, a wiring layer, a metal substrate or the like to form a resin composition sheet, a wiring board material, a wiring board, or the like to which a metal foil is attached. Therefore, the depressed portion of the surface of the resin composition sheet forms bubbles at the interface with the metal foil, the wiring layer, the metal substrate, or the like. Hereinafter, this bubble may be referred to as &quot; interfacial bubble &quot;. When a wiring board material or a wiring board is formed using the resin composition sheet, the interfacial bubbles contained therein become a starting point of the insulation breakdown, thereby lowering the dielectric breakdown voltage of the wiring board material and the wiring board.

However, when the content of the interfacial bubbles is small, the resin composition sheet flows and the interfacial bubbles disappear by the pressurization heating (so-called curing heating for the C stage) at the time of manufacturing the wiring board material. Thus, in the conventional resin composition sheet, interfacial bubbles are destroyed by pressurization heating in the C stage, and after the C stage, no interfacial bubbles exist. Specifically, a method for increasing the fluidity of the resin composition sheet at the time of pressurization heating in the production of a wiring board material has been studied.

However, when the fluidity of the resin composition sheet at the time of pressurization heating is too high, the resin composition sheet flows out from the end portion of the wiring board material by pressurization heating at the time of producing the wiring board material, The thickness is changed, and the thickness is sometimes varied. This variation in thickness causes variations in the performance of the metal base plate material in the plane. Further, the resin composition sheet flows out from the end portion, whereby the workability is lowered.

In particular, it has become clear that when the filling ratio of the insulating inorganic filler is increased to improve the thermal conductivity, the surface of the resin composition sheet is depressed much and the interfacial bubbles are increased. In the case where a large number of interfacial bubbles are present, the interfacial bubbles may not completely disappear in the conventional method.

Therefore, in the present invention, by suppressing the occupation ratio of the concave portion on the surface of the resin composition sheet to a specific range or less in the B-stage state before bonding with the metal foil, the wiring layer, the metal substrate or the like, Further, the lowering of the breakdown voltage is suppressed. Particularly, it is advantageous for the occupancy rate of the concave portion on the surface of the resin composition sheet to be 4% or less in terms of the area ratio to suppress the lowering of the breakdown voltage. It is also made clear that a certain size of the depressed portion on the surface of the resin composition sheet has a great influence on the lowering of the breakdown voltage and it is preferable that a portion having a maximum depth of 0.5 mu m or more, .

The present invention also provides a method for producing a resin composition sheet which is capable of suppressing generation of interfacial bubbles by a method other than the fluidity of the resin composition sheet at the time of pressure heating, Can be solved.

That is, in the conventional resin sheet, the breakdown voltage is improved by filling the concave portion by improving the flowability of the resin, regardless of the occupancy rate of the concave portion. However, the thickness of the metal base board material in one plane, And the like.

On the other hand, in the resin composition sheet of the present invention, by setting the occupation ratio of the concave portion having the maximum depth of 0.5 탆 or more on the surface to 4% or less as the area ratio, the concave portion is sufficiently filled without improving the fluidity of the resin, . It is also possible to solve the problem of variations in thickness in the plane of the metal base wiring board material and lowering of workability due to leakage of the resin composition.

As a method for producing a resin composition sheet of the present invention wherein the occupation ratio of the concave portion having the maximum depth of 0.5 占 퐉 or more on the surface is 4% or less in terms of area ratio, for example, (1) the kind and amount of the insulating inorganic filler are adjusted (2) a method of adjusting the viscosity of a resin composition used in producing a resin composition sheet, (3) a method of preparing two resin composition sheets at the time of producing the resin composition sheet, A method of lowering the occupancy rate of the concave portion of the surface by heating the resin composition sheet, and (4) a method of smoothing the surface of the resin composition sheet.

Here, the occupancy rate of the concave portion in the present invention is defined as the ratio of the area calculated from the sum of the areas of the concave portions observed to the total area of the range in which the concave portions on the surface of the resin composition sheet are observed. More specifically, it is expressed by the following expression.

(%) = (Area calculated from the sum of the areas of the concavities observed) / (total area in the range where the concavities were observed) x 100

Observation of the concave portion in the present invention can be performed by a scanning electron microscope (SEM), an optical microscope, a laser microscope, and a light interference microscope.

In order to measure the occupation rate of the concave portion of the resin composition sheet surface in a resin composition sheet, a metal base wiring board material, a metal base wiring board or the like having a metal foil after the metal foil, wiring layer or metal substrate is bonded, In the case where the substrate or the like can be peeled off, the concave portion on the surface of the resin composition sheet after peeling is observed and found by the above formula. When the metal foil, the wiring layer, the metal substrate, or the like can not be peeled off, the occupation rate of the recess can be evaluated by observation of the cross section. In this case, the square of the ratio of the sum of the lengths of the widths of the observed interface bubbles to the total length of the range in which the cross-section is observed is defined as the recess portion occupancy rate (%).

In the present invention, the occupancy rate of the concave portion is preferably 4% or less from the viewpoint of improving the breakdown voltage, and preferably 3% or less in order to more reliably improve the breakdown voltage. And more preferably 2% or less in order to more reliably improve the dielectric breakdown voltage.

Specifically, as a method for adjusting the occupancy rate of the concave portion on the surface of the resin composition sheet, for example, (1) a method of adjusting the kind and amount of the insulating inorganic filler, (2) (3) a method in which two sheets of resin composition sheets are produced at the time of producing a resin composition sheet and the two sheets are combined to lower the occupancy rate of the concave portion of the surface; and (4) And a step of smoothing the surface of the resin composition sheet.

More specifically, in (1), the insulating inorganic filler is mixed with different particle diameters such as large-diameter particles, medium-diameter particles and small-diameter particles, and the mixing ratio thereof is determined according to JIS-K-5101-13-2 And the like are mixed so as to minimize the absorption ratio and the like. Thereby, even if the fill factor of the insulating inorganic filler is increased to improve the thermal conductivity, the resin can be filled between the fillers, and the area ratio of the concave portion of the resin composition sheet can be reduced.

(2), it is preferable to add a solvent or the like in order to lower the viscosity of the resin composition to a viscosity suitable for coating. When the amount of the solvent to be added is adjusted to a proper amount or less, the occurrence of concave portions due to volatilization of a solvent or the like is suppressed.

(3), two or more sheets of the resin composition may be bonded by a known method such as a laminator or a press machine. Since the resin composition sheets are well fused, the resin composition sheets can be bonded together and a single resin sheet can be formed. Therefore, for example, when the one surface of the resin composition sheet has a high area ratio of the concave portion or when the concave and convex portions are formed, the concave and convex portions can be lost by bonding the surfaces to each other. Therefore, it is possible to reduce the occupancy rate of the concave portion on the surface of the resin composition sheet.

In the step (4), a method in which the resin composition sheet is subjected to pressurization heating in the case of bonding one sheet of the resin composition sheet or two sheets of the resin composition sheet (3) may be used. Thereby, it is possible to reduce the recesses that have occurred at the interface between the resin composition sheet and the substrate, that is, the interface between the resin composition sheet and the substrate. Further, when the base material which is in contact with the resin composition sheet is smooth and the surface irregularities are small at the time of pressurization heating, the recesses that have occurred at the interface between the resin composition sheet and the base material are likely to be reduced.

However, the present invention is not limited to these methods.

Hereinafter, materials and properties used for the resin composition sheet will be described.

The first resin composition sheet of the present invention is formed of a resin composition containing a thermosetting resin, a phenol resin, and an insulating inorganic filler. The resin composition sheet of the present invention may further contain other components as required.

In the second resin composition sheet of the present invention, if the minimum melt viscosity is within the above range, the composition is not particularly limited. However, similarly to the first resin composition sheet, the second resin composition sheet contains a thermosetting resin, a phenol resin and an insulating inorganic filler . A method of measuring the lowest melt viscosity will be described later.

(Thermosetting resin)

The resin composition sheet of the present invention contains at least one kind of thermosetting resin. The thermosetting resin is not particularly limited as long as it is a thermosetting resin, and a thermosetting resin that is conventionally used can be used. Specific examples of the thermosetting resin include an epoxy resin, a polyimide resin, a polyamideimide resin, a triazine resin, a phenol resin, a melamine resin, a polyester resin, a cyanate ester resin, And a modification system of a resin. These resins may be used alone or in combination of two or more.

From the viewpoint of heat resistance, the thermosetting resin in the present invention is preferably a resin selected from an epoxy resin and a triazine resin, more preferably an epoxy resin. If necessary, a hardening agent or a hardening accelerator may be contained. The epoxy resin may be used alone, or two or more epoxy resins may be used in combination.

Examples of the epoxy resin (hereinafter sometimes simply referred to as "epoxy resin") include bisphenol A, bisphenol F, biphenol, novolac phenol resin, orthocresol novolac phenol resin, trisphenol methanovolac phenol resin Polyglycidyl ethers obtained by reacting polyhydric alcohols such as polyhydric phenols and 1,4-butanediol with epichlorohydrin; polyglycidyl esters obtained by reacting polybasic acids such as phthalic acid and hexahydrophthalic acid with epichlorohydrin ; N-glycidyl derivatives of amines, amides, or compounds having a heterocyclic nitrogen base; and alicyclic epoxy resins.

Of these epoxy resins, an epoxy monomer having a mesogen skeleton represented by a biphenyl structure or a polymer thereof is preferable in that the thermal conductivity of the resin itself is improved and the melt viscosity at the time of heating is reduced.

The mesogen skeleton in the present invention refers to a functional group capable of exhibiting liquid crystallinity. Specific examples thereof include biphenyl, phenylbenzoate, azobenzene, stilbene, and derivatives thereof, and those having three or more six-membered ring structures in the biphenyl or the molecule are mentioned, and "liquid crystal handbook" (A), which is described in the &quot; Liquid Crystal Display Handbook &quot;

(2)

In the general formula (A), the ring structures represented by rings 1, 2, and 3 are each independently

(3)

And the couplers X1 and X2 are each independently a single bond,

[Chemical Formula 4]

Y1, Y2 and Y3 each independently represent -R, -OR (R represents an aliphatic hydrocarbon group having 1 to 8 carbon atoms), -F, -Cl, -Br, -I , -CN, -NO _2, or -CO-CH ₃ , And n, m and 1 each independently represent an integer of 0 to 4.

Examples of the epoxy monomer having a mesogen skeleton include a biphenyl type epoxy resin, a non-arylenyl type epoxy resin, 1- (3-methyl-4-oxiranylmethoxyphenyl) -4- (4-oxiranylmethoxyphenyl) -Cyclohexene or 1- (3-methyl-4-oxiranylmethoxyphenyl) -4- (4-oxiranylmethoxyphenyl) -benzene and the like are preferable. From the viewpoints of the melting point and the thermal conductivity of the cured product, 1- (3-methyl-4-oxiranylmethoxyphenyl) -4- (4-oxiranylmethoxyphenyl) -1-cyclohexene is more preferable. Such an epoxy compound can be produced, for example, by the method described in Patent Document 1 described above.

Among the epoxy monomers having the mesogen skeleton or the polymer thereof, those containing at least one bifunctional epoxy resin having a biphenyl skeleton are preferred. The bifunctional epoxy resin having a biphenyl skeleton is not particularly limited as long as it contains at least one biphenyl skeleton and has two epoxy groups. Specific examples thereof include biphenyl type epoxy resins and biphenylene type epoxy resins.

As the biphenyl type epoxy resin, an epoxy resin represented by the following general formula (III) is preferably used.

[Chemical Formula 5]

In the general formula (III), R ¹ to R ⁸ Each independently represent a hydrogen atom or a substituted or unsubstituted hydrocarbon group of 1 to 10 carbon atoms, and n represents an integer of 0 to 3;

Examples of the substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, an isopropyl group, and an isobutyl group. Among them, R ¹ to R ⁸ Are each independently a hydrogen atom or a methyl group.

Examples of the biphenyl type epoxy resin represented by the above general formula (III) include 4,4'-bis (2,3-epoxypropoxy) biphenyl or 4,4'-bis (2,3- Epoxy, 3,3 ', 5,5'-tetramethylbiphenyl as the main component, epichlorohydrin and 4,4'-biphenol or 4,4' - (3,3 ' 5'-tetramethyl) biphenol, and the like. Among them, an epoxy resin containing 4,4'-bis (2,3-epoxypropoxy) -3,3 ', 5,5'-tetramethylbiphenyl as a main component is preferable. Examples of such compounds are commercially available products such as YX-4000 (manufactured by Japan Epoxy Resin Co., Ltd.), YL-6121H (manufactured by Japan Epoxy Resin Co., Ltd.), YSLV-80XY (manufactured by Toto Chemical Co., Ltd.)

Examples of the biphenylene type epoxy resin include an epoxy resin represented by the following general formula (IV).

[Chemical Formula 6]

In the general formula (IV), R ¹ to R ⁹ Each independently represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an aralkyl group having 7 to 10 carbon atoms, and n represents an integer of 0 to 10 .

Examples of the alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, an isopropyl group, and an isobutyl group. Examples of the alkoxy group having 1 to 10 carbon atoms include a methoxy group, an ethoxy group, a propoxy group, and a butoxy group. Examples of the aryl group having 6 to 10 carbon atoms include a phenyl group, a tolyl group and a xylyl group. Examples of the aralkyl group having 7 to 10 carbon atoms include a benzyl group and a phenethyl group. Among them, R ¹ to R ⁹ Are each independently a hydrogen atom or a methyl group.

As the biphenyl type epoxy resin represented by the general formula (IV), for example, NC-3000 (trade name, manufactured by Nippon Yakushin KK) is available as a commercial product.

The bifunctional epoxy resin having a biphenyl skeleton in the present invention is preferably at least one compound selected from the group consisting of compounds represented by the general formula (III) or the general formula (IV) in view of thermal conductivity, electrical insulation, And more preferably at least one kind of compound represented by the general formula (III).

The content of the thermosetting resin in the total solid content of the resin composition sheet of the present invention is not particularly limited, but is preferably from 1% by mass to 15% by mass, more preferably from 2% by mass to 2% by mass from the viewpoint of thermal conductivity, More preferably from 12% by mass to 12% by mass, and still more preferably from 3% by mass to 10% by mass.

In the resin composition sheet of the present invention, the bifunctional epoxy resin having a biphenyl skeleton may be used in combination with other epoxy resin. As the other epoxy resins, conventionally known epoxy resins can be used without particular limitation, provided that they do not have a biphenyl skeleton.

Specific examples of the other epoxy resin include phenol novolak type epoxy resin, orthocresol novolak type epoxy resin, phenol including epoxy resin having a triphenyl methane skeleton, cresol, xylenol, resorcin, catechol , A phenol such as bisphenol A or bisphenol F and / or a compound having an aldehyde group such as formaldehyde, acetaldehyde, propionaldehyde, benzaldehyde or salicylaldehyde and a naphthol such as? -Naphthol,? -Naphthol or dihydroxynaphthalene And epoxidized novolac resins obtained by condensation or co-condensation in the presence of an acidic catalyst.

Also, glycidyl ester type epoxy resins obtained by reaction of polybasic acids such as bisphenol A, bisphenol F, bisphenol S, stilbene type epoxy resins, hydroquinone type epoxy resins, phthalic acid and dimeric acid with epichlorohydrin, A glycidylamine type epoxy resin obtained by the reaction of polyamines such as phenylmethane and isocyanuric acid with epichlorohydrin, an epoxy resin of a cocondensation resin of dicyclopentadiene and a phenol, an epoxy resin having a naphthalene ring, · Aralkyl resins, phenol · aralkyl resins containing a biphenylene skeleton, epoxides of aralkyl type phenolic resins such as naphthol · aralkyl resins, trimethylolpropane type epoxy resins, terpene modified epoxy resins, A linear aliphatic epoxy resin obtained by oxidation with a peroxide such as acetic acid, an alicyclic epoxy resin, a sulfur atom Oil there may be mentioned epoxy resins, may be used alone or in combination of two or more thereof.

The resin composition sheet of the present invention preferably contains at least one kind selected from an epoxy resin having a naphthalene ring from the viewpoint of flexibility in the B stage sheet.

When the resin composition sheet of the present invention contains other epoxy resin, the content thereof is not particularly limited, but is preferably 1% by mass to 30% by mass based on the bifunctional epoxy resin having the biphenyl skeleton , More preferably from 2% by mass to 20% by mass, and still more preferably from 3% by mass to 15% by mass. Such a content ratio improves the thermal conductivity, the electrical insulation, and the flexibility of the B stage sheet more effectively.

(Phenolic resin)

The resin composition sheet of the present invention contains at least one kind of phenolic resin. It is preferable that the phenol resin contains a phenol resin containing at least one compound having a structural unit represented by the following general formula (I) (hereinafter sometimes referred to as &quot; novolak resin &quot;). The phenolic resin functions as a curing agent of, for example, an epoxy resin.

By containing a phenol resin having a specific structure, the thermal conductivity is effectively improved and the usable time in the state before curing can be sufficiently long.

(7)

In the above general formula (I), R ¹ Represents an alkyl group, an aryl group, or an aralkyl group. The alkyl group, aryl group and aralkyl group represented by R ¹ may further have a substituent, if any, and examples of the substituent include an alkyl group, an aryl group, a halogen atom and a hydroxyl group.

m represents an integer of 0 to 2, and when m is 2, two R &lt; ^{1 &gt;} May be the same or different. In the present invention, m is preferably 0 or 1, and more preferably 0. n represents an integer of 1 to 10, preferably 1 to 8, more preferably 1 to 7.

In the general formula (I), R ² and R ³ Each independently represent a hydrogen atom, an alkyl group, an aryl group, a phenyl group or an aralkyl group. The alkyl group, phenyl group, aryl group and aralkyl group represented by R ² and R ³ may further have a substituent, if any. Examples of the substituent include an alkyl group, an aryl group, a halogen atom, and a hydroxyl group.

As R ² and R ³ in the present invention, a hydrogen atom, an alkyl group, a phenyl group or an aryl group is preferable from the viewpoints of storage stability and thermal conductivity, and a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or an aryl group having 3 to 6 carbon atoms , More preferably a phenyl group, and still more preferably a hydrogen atom.

From the viewpoint of heat resistance, R ² and R ³ Is preferably an aryl group.

The phenol resin in the present invention may contain one compound having a structural unit represented by the above general formula (I) alone or two or more kinds thereof.

The phenol resin represented by the above-mentioned general formula (I) is a phenolic compound containing a partial structure derived from resorcinol, but further contains at least one partial structure derived from a phenolic compound other than resorcinol do. Examples of phenolic compounds other than resorcinol include phenol, cresol, catechol, hydroquinone, and the like. The phenolic resin may contain a partial structure derived therefrom as a single species or a combination of two or more species.

Here, the partial structure derived from the phenolic compound means a monovalent or divalent group formed by removing one or two hydrogen atoms from the benzene ring portion of the phenolic compound. The position at which the hydrogen atom is removed is not particularly limited.

The partial structure derived from a phenolic compound other than resorcinol in the present invention is preferably a partial structure derived from a phenolic compound other than resorcinol from the viewpoints of thermal conductivity, adhesiveness and storage stability, phenol, cresol, catechol, hydroquinone, 1,2,3-trihydroxybenzene , 1,2,4-trihydroxybenzene, and 1,3,5-trihydroxybenzene, and is preferably a partial structure derived from at least one selected from catechol and hydroquinone More preferably a partial structure derived from a species.

The content ratio of the partial structure derived from resorcinol in the phenol resin is not particularly limited. However, from the viewpoints of the thermal conductivity and the storage stability, the content of the partial structure derived from resorcinol relative to the total mass of the phenol resin Is preferably 30 mass% or more, more preferably 55 mass% or more, and even more preferably 80 mass% or more.

Specifically, the phenol resin in the present invention is preferably a phenol resin containing a compound having a partial structure represented by any one of the following general formulas (Ia) to (If) shown below.

[Chemical Formula 8]

In the phenol resin in the present invention, the compound having the structural unit represented by the general formula (I) is preferably at least one compound represented by the following general formula (II).

[Chemical Formula 9]

In the formula (II), R &lt; ¹¹ &gt; Represents a hydrogen atom or a monovalent group derived from a phenolic compound represented by the following formula (IIp), and R &lt; ¹² &gt; Represents a monovalent group derived from a phenolic compound. ^{Further, R 1, R 2, R} 3, m and n are the same ^{R 1, R 2, R 3} , m and n and copper each in the formula (I).

The monovalent group derived from the phenolic compound represented by R ¹¹ and R ¹² is a monovalent group formed by removing one hydrogen atom from the benzene ring portion of the phenolic compound and the position at which the hydrogen atom is removed is not particularly limited.

[Chemical formula 10]

In the general formula (IIp), p represents an integer of 1 to 3. Also, R ¹ , R ² and R ³ Is in the formula (I) R ^1, R ² and R ³ And m represents an integer of 0 to 2.

The phenolic compound in R ¹¹ and R ¹² is not particularly limited as long as it is a compound having a phenolic hydroxyl group. Specific examples thereof include phenol, cresol, catechol, resorcinol, hydroquinone, and the like. Among them, at least one selected from cresol, catechol and resorcinol is preferable in terms of thermal conductivity and storage stability.

In the resin composition sheet of the present invention, the phenol resin containing the compound having the structural unit represented by the general formula (I) may contain a monomer which is a phenolic compound constituting the phenolic resin. The content ratio (hereinafter also referred to as &quot; monomer content ratio &quot;) of the monomer as the phenolic compound constituting the phenol resin is not particularly limited, but is preferably 5 to 80 mass%, more preferably 15 to 60 mass% , More preferably from 20 to 50 mass%.

When the content of the monomer is 5 mass% or more, the viscosity of the phenol resin is suppressed from increasing, and the adhesion of the inorganic filler is further improved. Further, when the content is 80% by mass or less, a higher-order higher-order structure is formed by the crosslinking reaction at the time of curing, and excellent heat conductivity and heat resistance can be achieved.

As the monomer of the phenolic compound constituting the phenol resin, resorcinol, catechol and hydroquinone can be mentioned, and it is preferable to contain at least resorcinol as a monomer.

The content of the phenolic resin in the resin composition sheet of the present invention is not particularly limited, but is preferably 1% by mass to 15% by mass in view of heat conductivity, electrical insulation, flexibility of the B- , More preferably from 2% by mass to 10% by mass.

The content of the thermosetting resin and the phenol resin (thermosetting resin / phenol resin) in the resin composition sheet of the present invention can be 0.6 to 1.5 on the basis of, for example, an equivalence ratio, and the thermal conductivity, the B- From the viewpoint of flexibility and usable time, it is preferably 0.8 to 1.2.

The resin composition sheet of the present invention may contain, in addition to the phenol resin, other curing agents other than the phenol resin, if necessary. As the other curing agent, conventionally known curing agents can be used without particular limitation. Specifically, for example, a mid-type curing agent such as an amine-based curing agent and a mercaptan-based curing agent, and a latent curing agent such as imidazole can be used.

(Insulating inorganic filler)

The insulating inorganic filler contained in the resin composition sheet of the present invention is not particularly limited as long as it is an insulating inorganic filler. And is preferably selected from silicon dioxide, aluminum oxide, magnesium oxide, beryllium oxide, boron nitride, aluminum nitride, silicon nitride, silicon carbide, aluminum fluoride, or calcium fluoride having a thermal conductivity of 1 W / mK or more . Of these, one kind or a mixture of two or more kinds may be used.

More preferably, it is an inorganic ceramic having a thermal conductivity of 10 W / mK or more, and is specifically selected from aluminum oxide, magnesium oxide, boron nitride, aluminum nitride, silicon nitride, silicon carbide, or aluminum fluoride.

Among them, aluminum oxide (alumina) having a volume resistivity of 10 ¹⁶ ? Cm or more is more preferable.

These may be used alone or in combination of two or more.

The particle diameter and the mixing ratio of the insulating inorganic filler are not particularly limited. With respect to the particle diameter and the mixing ratio of the insulating inorganic filler, for example, when three types of inorganic filler groups having different particle size distributions are applied, particles corresponding to 50% cumulative cumulative particle size distribution on the small particle diameter side (A) having a diameter D50 of not less than 5 占 퐉 and not more than 100 占 퐉, an inorganic filler group (D) having D50 of not less than 1/2 of the inorganic filler group (A) and not less than 1 占 퐉 and not more than 10 占 퐉, (A), (B) and (C) of inorganic filler group (C) with respect to the total amount of inorganic filler, wherein the filler group (B) ) Of the inorganic filler groups (A), (B) and (C) is 40 mass% or more and 90 mass% or less, 5 mass% or more and 40 mass% or less and 1 mass% or more and 30 mass% % By mass is 100% by mass).

When an inorganic filler whose particle size distribution has a wide range is used, it may be difficult to clearly separate the particle size distribution after mixing. In such a case, it is preferable to determine the maximum particle diameter in consideration of the film thickness to be designed, and then design the particle size distribution so as to match the conventional knowledge such as the Fuller curve on the large particle diameter side when the weight cumulative particle size distribution is drawn.

The average particle diameter and the maximum of the inorganic filler group (A) are limited by the target film thickness in the case of the sheet or the metal foil on which the resin is adhered. In the absence of other restrictions, it is preferable that the average particle diameter of the inorganic filler group (A) is as large as possible from the viewpoint of the thermal conductivity, but from the viewpoint of heat resistance, . From the viewpoint of the insulating property, the maximum particle diameter is preferably at least 7/8 of the film thickness, preferably 2/3 or less, more preferably 1/2 or less. Therefore, it is preferable that the average particle diameter of the inorganic filler group (A) is 1/2 or less of the film thickness, more preferably 5 占 퐉 or more and 100 占 퐉 or less, and from the viewpoint of filling property and heat resistance / And more preferably 10 m or more and 45 m or less.

In the present invention, the particle diameter D50 of the insulating inorganic filler is measured using a laser diffraction method, and corresponds to the particle diameter at which the weight accumulation is 50% when the weight cumulative particle size distribution curve is drawn on the small particle diameter side.

The particle size distribution measurement using the laser diffraction method can be carried out using a laser diffraction scattering particle size distribution measuring apparatus (for example, LS230 manufactured by Beckman Coulter, Inc.).

When the inorganic filler group (A) and the inorganic filler group (B) are alumina fillers, alumina fillers composed of single-crystal particles of -alumina are more preferable.

On the other hand, when the inorganic filler group (C) is an alumina filler, it is preferably? -Alumina,? -Alumina,? -Alumina or? -Alumina, more preferably? -Alumina, And more preferably an alumina filler composed of single crystal particles.

The content of the insulating inorganic filler contained in the resin composition sheet of the present invention is not particularly limited, but it may be 40 vol.% To 82 vol.% Of the solid content constituting the resin composition sheet. The thermal conductivity, the electrical insulating property, , More preferably from 50 vol% to 79 vol%, and still more preferably from 55 vol% to 76 vol%. If the total volume of the insulating inorganic filler is too small, the thermal conductivity becomes low, and if it is too much, it becomes difficult to form the sheet material.

The solid content in the resin composition sheet means a residue obtained by removing volatile components from the components constituting the resin composition sheet.

As the inorganic filler groups (A) to (C), commercially available ones can be appropriately selected. Further, by calcining an alumina filler which becomes a transition alumina, for example, by transitional alumina or heat treatment in an atmosphere gas containing hydrogen chloride (see, for example, JP-A-6-191833, JP-A-6-191836 See, for example, US Pat.

In addition to the inorganic filler groups (A) to (C), the resin composition sheet of the present invention may contain inorganic fibers containing alumina as a main component and having a number average fiber diameter of 1 to 50 탆. In the present invention, "inorganic fiber containing alumina as a main component" means inorganic fiber containing 41 vol% or more of alumina. Among them, inorganic fibers containing alumina at 58 vol% or more are preferable, and inorganic fibers containing alumina at 74 vol% or more are more preferable. The number average fiber diameter of the inorganic fibers is 1 to 50 탆, preferably 1 to 30 탆, and more preferably 1 to 20 탆. The fiber length of such an inorganic fiber is usually 0.1 mm to 100 mm.

Specific examples of such inorganic fibers include those commercially available under the trade names of Altex (manufactured by Sumitomo Chemical Co., Ltd.), Denkalkalen (manufactured by Denki Kagaku Kogyo Co., Ltd.), Maftek Bulk Fiber (manufactured by Mitsubishi Chemical Industry Corporation) And the like.

The amount of the inorganic fibers used is usually 4 vol% to 58 vol%, preferably 4 vol% to 41 vol%, with respect to the mass of the inorganic filler groups (A) to (C) The amount of the total amount of the insulating inorganic filler and the inorganic fiber in the solid content of the resin composition sheet is usually 30 to 95% by mass.

In addition to the insulating inorganic filler, the resin composition sheet of the present invention may further contain an inorganic filler other than the insulating inorganic filler, if necessary. Examples of the inorganic filler include magnesium oxide, aluminum nitride, boron nitride, silicon nitride, silicon oxide, aluminum hydroxide, and barium sulfate, which are non-conductive. Examples of conductive materials include gold, silver, nickel, and copper. These inorganic fillers may be used singly or in combination of two or more.

(Other components)

The resin composition sheet of the present invention may contain other components as necessary in addition to the above essential components. Other components include, for example, solvents, silane coupling agents, dispersants, and anti-settling agents.

The solvent is not particularly limited as long as it does not inhibit the curing reaction of the resin composition sheet, and a commonly used organic solvent can be appropriately selected and used.

The resin composition sheet of the present invention preferably contains a silane coupling agent. By the inclusion of the silane coupling agent, the function of forming a covalent bond (corresponding to binder) between the surface of the insulating inorganic filler and the organic resin surrounding the insulating filler can be achieved, and the function of efficiently transferring heat, Thereby contributing to an improvement in insulation reliability.

As a silane coupling agent, a commercially available silane coupling agent can be generally used. Considering the compatibility with an epoxy resin or a phenol resin and the reduction of heat conduction loss at the interface between the resin layer and the insulating inorganic filler, it is preferable that an epoxy group, It is preferable to use a silane coupling agent having a hydroxyl group, a hydroxyl group, a hydroxyl group, a hydroxyl group, a hydroxyl group.

Specific examples thereof include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropylmethyldimethoxysilane Aminopropyltrimethoxysilane, 3- (2-aminoethyl) aminopropyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, Aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-phenylaminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptotriethoxysilane, 3-ureidopropyl Triethoxysilane and the like, and silane coupling agent oligomers represented by SC-6000KS2 (manufactured by Hitachi Chemical Co., Ltd.) can also be used. These silane coupling agents may be used alone or in combination of two or more.

A dispersing agent can be added to the resin composition sheet of the present invention, and as the dispersing agent, a commercially available dispersing agent which is effective for dispersing the insulating inorganic filler can be usually used. For example, Ajisper series manufactured by Ajinomoto Fine Tech Co., Ltd., HIPLAAD series manufactured by Kusumoto Chemical Co., Ltd., Kao Homogenol series manufactured by Kusumoto Chemical Co., Ltd., and the like. These dispersants may be used in combination of two or more.

(Resin composition)

In the present invention, the resin composition sheet may be used to form the resin composition sheet. The resin composition contains the thermosetting resin, the phenol resin, and the insulating inorganic filler. Since the resin composition is filled with the insulating inorganic filler, the behavior of the insulating inorganic filler when the resin composition is applied on the substrate affects the occupancy rate of the concave portion described above.

When the viscosity of the resin composition is too low, the insulating inorganic filler precipitates on the side of the application substrate faster than the evaporation of the organic solvent contained in the resin composition, and forms a wall of the insulating inorganic filler. As a result, volatile substances such as a solvent contained in the resin composition on the side of the coating base material are clogged by the walls of the insulating inorganic filler to form bubbles more than the walls of the insulating inorganic filler. As a result, interfacial bubbles are generated on the coated substrate side. Therefore, in order to reduce the occupancy rate of the concave portion of the resin composition sheet of the present invention, viscosity control of the resin composition imparted on the substrate becomes important. Particularly, when the resin composition is applied to the metal foil and the resin composition sheet is formed on the metal foil, it is clear that adjustment of the viscosity of the resin composition is important because the surface roughness of the metal foil is generally rougher than that of the metal substrate.

The viscosity of the resin composition was measured by a B-type viscometer (spindle No. 4, rotation number 30 rpm) at 25 캜. In order to effectively suppress the occurrence of interfacial bubbles, it is preferably from 1000 to 10,000 mPa · s, more preferably from 1200 to 8000 mPa · s, even more preferably from 1500 to 6000 mPa · s. If the viscosity is too low, the deposition of the insulating inorganic filler is rapid, and interface bubbles are easily generated. On the other hand, if the viscosity is too high, it becomes difficult to control the film thickness of the coating film. Particularly, when a resin composition sheet having a low viscosity is coated on a metal foil to prepare a resin composition sheet having a metal foil attached thereto, if the viscosity is 1000 mPa or more, the settling of the insulating inorganic filler is suppressed from becoming too rapid, And the insulating inorganic filler is prevented from being generated.

In the resin composition containing the insulating inorganic filler, the more the content of the insulating inorganic filler is, the higher the viscosity of the resin composition becomes, and the coating with a uniform film thickness becomes difficult. However, if the viscosity is lowered by increasing the addition amount of a solvent or the like, the settling of the insulating inorganic filler becomes too fast as described above, and the occupancy rate of the concave portion increases. Therefore, it is preferable to adjust the resin composition to an appropriate viscosity.

(Production method of resin composition sheet (B stage)) [

The resin composition sheet of the present invention is a semi-cured (B-stage) sheet-like article. When the resin composition sheet in the semi-cured state (B stage) is used in a wiring board material or a wiring board and finally cured, it becomes a thermally conductive insulating layer.

The resin composition sheet is produced by applying the resin composition on a supporting substrate (coated substrate) to form a sheet-like coating, and heating the coated composition to a semi-cured state (B stage).

The method of applying the resin composition is not particularly limited, but when it is formed in a large area, the application is preferable. The application can be carried out by a known method. Specific examples of the application method include a comma coat, a die coat, a lip coat, and a gravure coat. As a coating method for forming the resin layer to a predetermined thickness, a comma coating method for passing the object between the gaps, a die coating method for applying a resin varnish whose flow rate is adjusted from a nozzle, and the like can be applied. Other examples include lip coats and gravure coats.

A solvent may be added to the resin composition for viscosity adjustment at the time of application. The solvent contained in the resin composition is not particularly limited, and methyl ethyl ketone, acetone, methyl isobutyl ketone, cyclohexanone, cyclohexanol, dimethylacetamide, isopropanol, methanol, ethanol and the like can be used.

The application substrate is not particularly limited, but is preferably removed from the plastic base material because it is removed when the metal base wiring board material is produced. Examples of the resin used for the plastic substrate include polystyrene resin, acrylic resin, polymethyl methacrylate resin, polycarbonate resin, polyvinyl chloride resin, polyvinylidene chloride resin, polyethylene resin, polypropylene resin, polyamide resin, polyamideimide A thermoplastic polyester resin such as a resin, a polyetherimide resin, a polyetheretherketone resin, a polyarylate resin, a polyacetal resin, a polybutylene terephthalate resin and a polyethylene terephthalate resin, a cellulose acetate resin, a fluororesin, a polysulfone resin , Polyethersulfone resin, polymethylpentene resin, polyurethane resin, phthalic acid diallyl resin, and thermosetting resin. The thickness of the plastic substrate is preferably 0.01 mm to 5 mm from the viewpoint of handleability. In order to improve the peelability of the resin composition sheet, a release layer may be formed on the surface of the plastic substrate.

The obtained coating material may be dried before heating for semi-curing. The drying temperature and the drying time are preferably adjusted appropriately according to the type of the organic solvent contained in the coating material. By adjusting the drying temperature and the drying time, it is also possible to make the occupation ratio of the concave portion of the obtained resin composition sheet surface to 4% or less by adjusting the evaporation rate of the organic solvent and the settling rate of the insulating inorganic filler to the coating substrate side.

Concretely, the drying temperature is preferably 30 ° C to 90 ° C, more preferably 40 ° C to 100 ° C, and further preferably 50 ° C to 110 ° C. The drying time is preferably 0.2 to 60 minutes, more preferably 0.5 to 40 minutes, and further preferably 1 to 30 minutes.

The obtained coating material is heated until it reaches a semi-cured state (B stage). Here, the term &quot; semi-cured state (B stage) &quot; refers to the lowest melt viscosity, which is 10 ³ to 10 ⁶ Pa · s at room temperature, while the viscosity decreases from 10 to 10 ³ Pa · s in the range of 80 ° C to 200 ° C State. Further, the sheet (thermally conductive insulating layer) of the C stage after the main curing is not melted by heating.

The melt viscosity of the terminally modified imide oligomer means the minimum value by the viscosity lowering due to the temperature rise and the viscosity increasing due to the curing reaction. A method of measuring the lowest melt viscosity of the resin composition sheet will be described later.

The heating temperature and the heating time for semi-curing are preferably adjusted appropriately according to the kind and amount of the organic solvent contained in the coating. Concretely, the heating temperature for semi-curing is preferably 70 ° C to 160 ° C, more preferably 80 ° C to 150 ° C, and further preferably 90 ° C to 140 ° C. The heating time for semi-curing is preferably 0.2 to 60 minutes, more preferably 0.5 to 40 minutes, and more preferably 1 to 30 minutes.

The content of the organic solvent in the resin composition sheet (B-stage sheet) is reduced to 40% or less of the content of the organic solvent in the resin composition before being applied on the substrate. From the viewpoint of suppressing generation of voids or bubbles.

The obtained resin composition sheet may be a single layer, or two resin composition sheets may be adhered to each other, or three or more resin composition sheets may be laminated. The bonding of the two or more sheets of the resin composition may be carried out by using a known method such as a laminator or a press machine, or may be heated to a semi-cured state (B stage).

By bonding two or more sheets of the resin composition composition in this manner, the resin composition sheets can be bonded together because the resin composition sheets are well fused together, and a single resin sheet can be formed. Therefore, for example, when the one surface of the resin composition sheet has a high area ratio of the concave portion or when the concave and convex portions are formed, the concave and convex portions can be lost by bonding the surfaces to each other. Therefore, it is possible to reduce the occupancy rate of the concave portion on the surface of the resin composition sheet.

The bonding of the resin composition sheet is preferably performed by heating at 70 to 160 캜, more preferably 80 to 150 캜, and further preferably 90 to 140 캜.

The pressure of the coalescing is preferably 0.05 MPa to 1 MPa, more preferably 0.1 MPa to 0.6 MPa, and still more preferably 0.2 MPa to 0.4 MPa.

The surface of the obtained resin composition sheet may be smoothed to lower the concave portion occupation rate of the surface. As a method of smoothing, for example, known methods such as a laminator and a press machine can be given. By smoothing, the resin composition sheet may be slightly flowed by pressurization to dislodge the concave portion of the sheet surface. It is preferable that the member brought into contact with the resin composition sheet at the time of smoothing is smooth. This is because the smoothness of the member affects the smoothness of the resin composition sheet. For example, a smooth plastic sheet may be brought into contact with the resin composition sheet, and at the same time, the resin composition sheet may be prevented from being attached to the laminator or the press machine. Further, the resin composition sheet may be heated at the time of pressurization to improve the fluidity of the resin composition. In this smoothing step, a semi-cured state (B stage) may be obtained by heating.

When the surface of the resin composition sheet is smoothed by a vacuum laminator, the degree of vacuum is preferably from 0.01 kPa to 20 kPa, more preferably from 0.03 kPa to 10 kPa, and further preferably from 0.1 kPa to 5 kPa.

The heating temperature of the vacuum laminator is preferably 70 ° C to 170 ° C, more preferably 80 ° C to 160 ° C, and further preferably 90 ° C to 150 ° C.

The pressure of the vacuum laminator is preferably 0.1 MPa to 3 MPa, more preferably 0.3 MPa to 2 MPa, and still more preferably 0.6 MPa to 1.5 MPa.

(Physical properties of resin composition sheet (B stage)) [

The minimum melt viscosity of the resin composition sheet affects the fluidity of the resin composition in the pressure heating step from the B stage to the C stage. Therefore, it is preferable to adjust the lowest melt viscosity at a temperature range of 20 ° C to 200 ° C, which is applied in the pressure heating step, from the viewpoint of handling convenience and suppressing the outflow of the resin composition sheet from the end portion.

The minimum melt viscosity of the resin composition sheet is a minimum value which is caused by a decrease in viscosity due to temperature rise and an increase in viscosity due to a curing reaction when the temperature dependence of shear viscoelasticity is measured.

Examples of conditions for measuring the shear viscoelasticity include a temperature raising rate of 5 deg. C / min (temperature raising rate of the press) and a frequency of 1 to 10 Hz, and a measuring jig for sandwiching a sheet is a circular plate. The sample may be prepared by laminating a resin composition sheet as necessary.

The minimum melt viscosity of the resin composition sheet at 20 ° C to 200 ° C is preferably 10 Pa · s to 1000 Pa · s, more preferably 20 Pa · s to 800 Pa · s, More preferably 600 Pa · s. If the minimum melt viscosity is too low, the thickness of the thermally conductive insulating layer will be varied. If the minimum melt viscosity is too high, the thermally conductive insulating layer will not sufficiently adhere to the adherend such as copper foil or metal substrate, The breakdown voltage is lowered. Therefore, when the minimum melt viscosity at 20 ° C to 200 ° C is within the above range, excellent fluidity is exhibited at the time of heating, and adhesion to an adherend having a concavo-convex structure is also followed.

The thickness of the resin composition sheet (B-stage sheet) of the present invention can be appropriately selected according to the purpose. For example, the average thickness is preferably 20 to 500 占 퐉, more preferably 25 to 400 占 퐉, From the viewpoint of electrical insulation and sheet flexibility, it is preferable that the thickness is 30 mu m to 300 mu m. The electrical insulation is excellent when the thickness is 20 mu m or more, and the increase in the thermal resistance is suppressed when the thickness is 500 mu m or less.

&Lt; Resin composition sheet with metal foil (B stage sheet) &gt;

The resin composition sheet to which the metal foil is attached is obtained by pasting a metal foil to the above resin composition sheet. More specifically, a metal foil can be bonded to a resin composition sheet by a known method using a laminator, a press machine or the like to produce a resin composition sheet having a metal foil. The resin composition sheet to which the metal foil is adhered can be produced by applying a resin composition with a metal foil as a base to form a coating and heating it to a semi-cured state (B stage).

Generally, the metal foil is roughened in order to enhance the adhesion with the resin composition sheet. In the case of producing a resin composition sheet with a metal foil by attaching the resin composition sheet to a metal foil, if the concave portion of the specific size is present on the surface of the resin composition sheet, the metal foil is roughened in the pressing and heating step of C- It is impossible to completely follow the surface shape, and interfacial bubbles can be easily generated.

In order to suppress the generation of such interfacial bubbles, the resin composition sheet of the present invention, that is, a resin composition sheet containing a thermosetting resin, a phenolic resin, and an insulating inorganic filler and having a recess having a maximum depth of 0.5 탆 or more on the surface, Or a second resin having a lowest melt viscosity at 20 ° C to 200 ° C of 10 to 1000 Pa · s and a recess having a maximum depth of 0.5 μm or more on the surface at a surface area of 4% It has been found effective to use a composition sheet. In addition, the resin composition sheet of the present invention effectively suppresses the generation of interfacial bubbles even when a metal substrate is laid.

As the metal foil, a metal foil made of any one material of copper, aluminum, nickel, tin, or an alloy containing them may be used. The layer structure of the metal foil is not limited to one layer, and a composite foil of two to three layers may be used. When low cost and high electric conductivity are required, it is preferable to use a copper foil.

The thickness of the metal foil is preferably 3 mu m to 110 mu m, more preferably 5 mu m to 90 mu m, and even more preferably 9 mu m to 70 mu m. When the thickness is 3 mu m or more, handling is excellent and folding with a slight force can be prevented. When the thickness is 110 μm or less, the amount of expensive metal foil to be used is suppressed.

In order to improve the handling property of the metal foil, the metal foil may be handled with the carrier film attached thereto. As such a carrier film, a tacky adhesive film, a self-adsorbing tacky film, and a UV curable tacky film can be used. It is possible to suppress the folding of the metal foil or the like due to the state in which the carrier film is attached to the metal foil in the step of adhering the metal substrate and the metal foil to the resin composition sheet or in the application step for obtaining the resin composition sheet with the metal foil.

Other manufacturing methods and manufacturing conditions, a preferable range of the thickness of the resin composition sheet, a preferable range of the viscosity of the resin composition, and the like are the same as those of the resin composition sheet.

&Lt; Heat-conductive insulating layer (C stage) &gt;

The thermally conductive insulating layer is an adhesive layer that insulates a metal substrate from a wiring layer or a metal foil in a metal base wiring board or a metal base wiring board material described later. The resin composition sheet (B stage) is finally cured (C stage) to form a thermally conductive insulating layer (C stage).

Specifically, the above-mentioned resin composition sheet is sandwiched between a metal substrate and a metal foil, and the metal substrate and the metal foil are bonded to each other by pressurizing and heating by a press machine or the like. The resin composition sheet in the semi-cured state (B stage) is re-melted in a pressurizing and heating step, and the resin composition sheet is adhered to the metal substrate and the metal foil, and then the resin composition sheet is finally cured (C stage), and the metal substrate and the metal foil are bonded. The thermally conductive insulating layer after the final curing is not melted by heating.

The thermally conductive insulating layer of the present invention is a composite of a thermally conductive insulating inorganic filler and a thermosetting resin. As the thermally conductive insulating inorganic filler, it is preferable to use inorganic ceramics having high thermal conductivity and insulating property. When a thermally conductive resin is used as the thermosetting resin, the thermal conductivity can be increased with a smaller filler content. In the present invention, it is preferable to use a bifunctional epoxy resin having a biphenyl skeleton as the thermally conductive resin.

The biphenyl skeleton of a bifunctional epoxy resin having a biphenyl skeleton has an anisotropic structure because it becomes a mesogen group. If the thermally conductive resin layer has an anisotropic structure inside, it exhibits a high thermal conductivity. Generally, the thermal conductivity of an insulator is mainly due to phonon, and thermal conductivity is lowered due to static scattering of phonons in defects in the material and dynamic scattering due to collision of phonons with each other due to molecular vibration or non-uniformity of lattice vibration.

However, the main chain direction of the polymer is higher than that in the direction perpendicular to the main chain (direction between molecular chains). This is because the main chain direction of the polymer is connected by a strong conjugate bond, so that the harmonics of vibration in the main chain direction (phonon) is high and defects causing static scattering of phonon are also much smaller than those between molecular chains . Therefore, by orienting the main chain of the polymer, the thermal conductivity can be increased anisotropically. The orientation of the main chain of the polymer is carried out by known methods such as stretching, electric field application, and rubbing. When the main chain of the polymer is oriented in the direction perpendicular to the film surface (thickness direction), the thermal conductivity in the thickness direction can be increased.

On the other hand, if the main chain of the polymer is oriented in the horizontal direction of the film surface, it becomes possible to increase the thermal conductivity in the film surface. On the other hand, in general, the thermal conductivity in the vertical direction between the molecular chains of the polymer is lower than that of the polymer not oriented. Therefore, in general, in the resin composition sheet in which the main chain of the polymer is oriented in the horizontal direction of the film surface, the thermal conductivity in the thickness direction is reduced.

However, if the orderliness of the material increases, the degree of harmonization of vibration increases and the degree of defects also decreases, so that the thermal conductivity in the molecular chain direction (thickness direction) can also be increased. Here, it is completely determined that the orderability of the material is the highest, but the complete crystal of the polymer insulator is practically impossible to be applied as an insulating adhesive material. On the other hand, the liquid crystal state has a high orderability following the determination and can be realized. Since the bifunctional epoxy resin having a biphenyl skeleton has a mesogen group, there are few defects in not only the main chain direction but also the intermolecular chain direction, and also the incombustibility of vibration is small. Therefore, it exhibits a large thermal conductivity without being caught in a specific orientation direction.

<Material of metal base board>

1 shows a cross-sectional structure of an example of a metal base wiring board material of the present invention.

The metal base plate material has a metal foil 30 and a metal substrate 20 and is provided between the metal foil 30 and the metal substrate 20 with a thermally conductive insulating layer 10 as a cured product of the resin composition sheet. The metal substrate 20 and the metal foil 30 are insulated by the arrangement of the thermally conductive insulating layer 10.

The metal substrate 20 is made of a metal material having a high thermal conductivity and a large heat capacity, and may be an alloy used for copper, aluminum, iron, and lead frames. The strength of the metal base board increases as the thickness of the metal base board 20 increases. However, when the metal base board on which the electronic components are mounted is integrated with a metal chassis or the like by screws or an adhesive material, ) Need not be particularly thick. The material of the metal substrate 20 may be selected in accordance with the purpose, such as aluminum in the case of weight reduction and workability being priority, and iron in the case of giving priority to the strength.

It is preferable that the metal base wiring board is manufactured in a large size and then cut to a size to be used after electronic component mounting because productivity is enhanced. Therefore, it is preferable that the metal substrate 20 has high workability for cutting.

As the aluminum metal substrate 20, aluminum or an alloy containing aluminum as a main component can be selected as a material, and various kinds of metals can be obtained depending on the chemical composition and the heat treatment conditions. However, the workability such as high and easy cutting is high , And it is preferable to select a type having excellent strength.

The metal base plate material is produced by a method in which the resin composition sheet is sandwiched between the metal substrate 20 and the metal foil 30 and heated under pressure with a press machine or the like. Or a method in which the resin composition sheet having the metal foil attached thereto and the metal substrate 20 are heated under pressure. The conditions of the heating and pressurizing treatment for curing the resin composition sheet are appropriately selected depending on the constitution of the resin composition sheet. For example, the heating temperature is preferably 80 to 250 占 폚, the pressure is preferably 0.5 to 8.0 MPa, the heating temperature is 130 to 230 占 폚, and the pressure is more preferably 1.5 to 5.0 MPa.

<Metal base board>

2 shows a cross-sectional structure of an example of the metal base wiring board of the present invention.

The metal base wiring board has a metal substrate 20 and a wiring layer 40 and a thermally conductive insulating layer 10 as a cured product of the resin composition sheet is provided between the metal substrate 20 and the wiring layer 40. The metal substrate 20 and the wiring layer 40 are insulated by the arrangement of the thermally conductive insulating layer 10.

The wiring layer 40 is obtained by wiring the metal foil 30 of the metal base wiring board material. As a method for wiring the metal foil 30, etching is industrially preferable.

It is preferable that the metal base wiring board is formed by removing a pad portion for mounting electronic components and forming a solder resist on the surface. The metal base plate material is preferably cut into a size of an electronic component mounting member such as an LED light source member after circuit processing and formation of a solder resist. For example, an electronic component is mounted by applying an electrical connection material such as solder to the pad portion of the metal base wiring board, arranging the electronic components, and then passing through the solder reflow process.

<LED light source member>

3 shows a cross-sectional structure of an LED light source member when an LED package is used as an electronic component. In the LED light source member shown in Fig. 3, the heat conductive insulating layer 10 is provided between the metal substrate 20 and the wiring layer 40, and the electronic component 50 is mounted on the wiring layer 40. [ By using this LED light source device, an LED backlight unit or the like can be manufactured, or LED lamps, LED bulbs, and the like can be manufactured.

Heat generated in the LED package is conducted in order of an electrical connecting material such as solder, a pad portion composed of the metal foil 30, a thermally conductive insulating layer 10, and a metal substrate 20 in order to dissipate heat. By using the thermally conductive insulating layer 10 which is a cured product of the resin composition sheet of the present invention, heat radiation from the pad portion to the metal substrate is improved, and temperature rise of the LED package can be suppressed.

Example

Hereinafter, the present invention will be described concretely with reference to Examples, but the present invention is not limited to these Examples. Unless otherwise stated, "parts" and "%" are on a mass basis.

[Example 1]

&Lt; Resin Synthesis Example 1 &

594 g of resorcinol, 66 g of catechol, 316.2 g of 37% formalin, 15 g of oxalic acid and 100 g of water were placed in a 3-liter separable flask equipped with a stirrer, a condenser and a thermometer, It has warmed up. The reaction was continued at reflux temperature for 4 hours.

Thereafter, while distilling off water, the temperature in the flask was raised to 170 占 폚. The reaction was continued for 8 hours while maintaining the temperature at 170 ° C. Thereafter, the mixture was concentrated under reduced pressure for 20 minutes to remove water and the like in the system, and a phenol resin having a structural unit represented by the general formula (I) was extracted. The phenol resin thus obtained had a number average molecular weight of 530 and a weight average molecular weight of 930. The phenol equivalent of the phenol resin was 65 g / eq. .

&Lt; Vanishy phase resin composition &gt;

56.80 g (63% (relative to the total mass of the insulating inorganic filler)) of an insulating inorganic filler having a particle diameter D50 of 18 占 퐉 (Sumiko Random A.Ma18, manufactured by Sumitomo Chemical Co., Ltd.) was placed in a container equipped with a 1 L cap made of polypropylene , 20.29 g (22.5% (relative to the total mass of the insulative inorganic filler)) of an insulating inorganic filler having a particle diameter D50 of 3 占 퐉 (Sumikomo Chemical Co., Ltd., Sumikonomam AA3), and an insulating inorganic filler having a particle diameter D50 13.07 g (14.5% (relative to the total mass of the insulating inorganic filler)) was weighed, and 0.099 g of a silane coupling agent (KBM403 manufactured by Shin-Etsu Chemical Co., Ltd.) and 2-buta (Manufactured by Wako Pure Chemical Industries, Ltd.), 0.180 g of a dispersant (ED-113, manufactured by Kusumoto Chemical Co., Ltd.) and 5.96 g of the phenol resin obtained in Synthesis Example 1 were added and stirred. 5.914 g of a bifunctional epoxy resin having a biphenyl skeleton (YL6121H manufactured by Mitsubishi Chemical Corporation), 0.657 g of a naphthalene-based epoxy resin (HP4032D, manufactured by DIC Corporation), 2 g of an imidazole compound (2 PHZ manufactured by Shikoku Kasei Kogyo Co., Was added. Further, 500 g of a ball made of zirconia having a diameter of 5 mm was charged and stirred on a ball mill base at 100 rpm for 48 hours, and then the ball made of zirconia was separated by filtration to obtain a varnish-type resin composition 1. Table 1 shows the particle diameter D50 of each insulating inorganic filler compounded and the weight ratio to the total mass of the insulating inorganic filler.

<Viscosity>

The viscosity of the resin composition 1 on the varnish at 25 캜 was measured by a B-type viscometer (spindle No. 4, revolutions 30 rpm). The measurement results are shown in Table 1.

<Resin Composition Sheet>

The resin composition 1 obtained above was coated on a PET film (A53 manufactured by Teijin Dupont Film Co., Ltd.) using a bar coater and dried at 100 캜 for 20 minutes. The film thickness after drying was 50 占 퐉. Two sheets of the resin composition sheets after drying were placed facing each other and laminated at 110 DEG C, 0.3 MPa, and a conveying speed of 0.3 m / min using a roll laminator to obtain a resin composition sheet (B stage sheet) having an average thickness of 100 mu m . The resulting resin composition sheet was excellent in flexibility.

<Containing Ratio of Insulating Inorganic Filler>

The ratio of the total insulating inorganic filler in the resin composition sheet was evaluated as follows. First, the weight of the resin composition sheet was measured, and the resin composition sheet was baked at 400 DEG C for 2 hours at 700 DEG C for 3 hours, and the resin component was evaporated to measure the mass of the remaining insulating inorganic filler, The weight ratio in the composition sheet was evaluated. Subsequently, the insulating inorganic filler was submerged in water, and the volume of the insulating inorganic filler was measured from the change of the water level. From this, the specific gravity of the insulating inorganic filler was evaluated. Then, the specific gravity of the resin composition sheet was evaluated in the same manner. Then, the weight ratio of the insulating inorganic filler in the resin sheet was divided by the specific gravity of the insulating inorganic filler, and the specific gravity of the resin sheet was integrated to evaluate the volume ratio of the insulating inorganic filler. The evaluation results are shown in Table 1.

&Lt; Minimum melt viscosity of resin composition sheet &gt;

The temperature dependency of the complex elastic modulus of the resin composition sheet was measured by a dynamic viscoelastic device (manufactured by Rheometric Scientific, Inc., ARES), and the temperature was divided by each frequency to obtain a complex viscosity.

Eight sheets of the resin composition sheets on which the PET film was peeled were stacked, and a sheet having a layer thickness of 0.8 mm was used as a measurement sample. The measurement sample was sandwiched by a measuring jig on a disk of 25 mm phi and a shearing operation was performed at 80 DEG C for 10 seconds. Thereafter, the complex viscosity in the temperature raising rate of 5 캜 / min, the frequency of 10 Hz, and the range of 20 캜 to 200 캜 was measured. And the lowest value of the complex viscosity at 20 캜 to 200 캜 was evaluated as the lowest melt viscosity.

&Lt; Occlusion Occurrence Rate of Resin Composition Sheet &gt;

The surface shape of the resin composition sheet was measured by a three-dimensional non-contact surface shape measuring system (MM3200, manufactured by Ryoka Corporation). And the surface shape was measured in the field of view of 250 占 퐉 占 190 占 퐉. Polarity approximation to the measured image data was subjected to second-order correction, and the approximated image was subtracted from the measured image data before the surface correction to obtain the corrected image data. Thus, the slope of the surface height of the resin composition sheet was corrected. Then, the area ratio of the portion higher than the threshold value (threshold value) was evaluated by a bearing analysis in which a value 0.5 mu m lower than the average height (flat portion) was set to a binarization threshold value (threshold value). Thus, the area ratio of the flat portion was evaluated. Subsequently, a value obtained by subtracting the area ratio from 100% was evaluated as the concave area ratio. This measurement and manipulation were repeated randomly 10 times with respect to the sample, and the area ratio occupied by the concave portion was averaged to obtain the concave portion occupancy rate of the sample. The results are shown in Table 1.

<Material of metal base board>

The resin composition sheet of 500 mm x 600 mm from which the PET was peeled was placed on a roughened screen side of a 550 mm x 650 mm copper foil (35 mu m thick, manufactured by Nippon Electric Works Co., Ltd.) and an aluminum substrate (A5052, t and pressurized under a vacuum of 3 kPa under a pressure of 2 MPa at 140 ° C for 2 hours and 190 ° C for 2 hours using a vacuum press press to obtain a metal base board material.

&Lt; Difference in thickness of thermally conductive insulating layer &

The thickness variation of the thermally conductive insulating layer was evaluated based on the presence or absence of irregularities on the copper foil surface. Further, when the metal base board material of the evaluation sample is enlarged to 500 mm x 600 mm, the deviation of the thermally conductive insulating layer appears as the irregularities of the copper foil surface.

<Measurement of Peel Strength>

According to JIS-C6481 (1996 edition), a 90 占 퐉 test piece was produced using the aluminum base substrate thus produced. The copper foil (35 占 퐉) having a width of 10 mm at the center was cut at a rate of 50 mm / min at room temperature using a tensile tensile tester (TM-100 manufactured by Orientec Co., Ltd.) by cutting the metal substrate to 25 mm x 100 mm. And the peel strength was measured from the average load again (multiple times).

<Electrical Insulation>

The obtained copper foil of the obtained metal base wiring board material was etched with an ammonium persulfate aqueous solution, leaving a round pattern of 20 mm phi. The breakdown voltage of 50 or more rounded patterns was measured by a withstand voltage measuring device (Puncture Tester PT-1011 manufactured by Tokyo TOA Electronics Ltd. Japan). The lowest dielectric breakdown voltage is shown in Table 1.

<Thermal Conductivity>

The copper foil and the aluminum substrate of the obtained metal base wiring board material were etched to obtain a thermally conductive insulating layer after final curing. An aqueous ammonium persulfate solution was used for etching the copper foil. Hydrochloric acid was used for etching the aluminum substrate. The thermal conductivity of the resulting thermally conductive insulating layer was determined as follows.

First, the frequency dependency of the phase difference of the temperature wave was measured using a temperature rupture analyzer (iphase mobile 1u, manufactured by Eye Phases Inc.). Subsequently, the slope of the phase difference with respect to the square root of the frequency was obtained in the range of frequency 200 to 400 Hz. The slope of the phase difference is -d (π / α) equal to ^0.5 and, therefore, was determined the thermal diffusion coefficient (α) from the gradient of the thickness (d) and the phase difference between the heat-conductive insulating layer.

Then, specific heat was measured with a differential scanning calorimeter (DSC, Ryerson 1, manufactured by Perkin Elmer), and the density was measured with an electronic specific gravity meter (AFMIRA Injection, SD-200L). Then, the thermal conductivity [W / mK] was obtained from the following equation. The obtained thermal conductivity is shown in Table 1.

Heat conductivity [W / mK] = Thermal Diffusion (Thermal Diffusion Coefficient (α)) [mm ² / s] × Specific Heat [J / kg · K] × Density [g /

[Example 2]

<Resin composition>

62.66 g (69.5% (relative to the total mass of alumina filler)) of an alumina filler (AS-20, manufactured by Showa Denko K.K.) having a particle diameter D50 of 20 mu m as an alumina filler was obtained in the same manner as in Example 1, 16.77 g (18.6% (relative to the total mass of the alumina filler)) of an alumina filler having a particle diameter D50 of 0.4 mu m (Sumiko Random AA3 manufactured by Sumitomo Chemical Co., Ltd.) The varnish-phase resin composition 2 was obtained in the same manner as in Example 1 except that 10.73 g (11.9% (relative to the total mass of the alumina filler)) and 13.5 g of 2-butanone (manufactured by Wako Pure Chemical Industries, And the viscosity was evaluated. Table 1 shows the particle diameter D50 of each insulating inorganic filler compounded and the weight ratio to the total mass of the insulating inorganic filler.

&Lt; Resin composition sheet with metal foil &

The resin composition 2 obtained above was applied on a roughened surface of a copper foil (35 mu m, manufactured by Nippon Denshi Co., Ltd.) using a bar coater and dried at 100 DEG C for 20 minutes. The film thickness after drying was 100 占 퐉. A PET film (manufactured by Teijin Dupont Film Co., Ltd., A53) was placed on the dried resin layer, and then, using a vacuum laminator (manufactured by Meiji Kogyo Co., Ltd.), under vacuum of 3 kPa or less at 130 캜 and 1 MPa Followed by a vacuum press for 15 seconds to obtain a resin composition sheet (B stage sheet) having a metal foil. The average thickness of the resin composition sheet in the resin composition sheet with the metal foil was 100 mu m.

The resulting resin composition sheet with the metal foil was evaluated for the occupancy rate of the concave portion in the same manner as in Example 1. [

In the same manner as in Example 1 except that the resin composition sheet was sandwiched between the copper foil and the aluminum substrate so that the resin composition sheet side in the resin composition sheet with the metal foil thus obtained was brought into contact with the aluminum substrate To prepare a metal base board material.

The obtained metal base board material was evaluated in terms of thickness variation, fill strength, electrical insulation, and thermal conductivity of the thermally conductive insulating layer in the same manner as in Example 1. [ The evaluation results are shown in Table 1.

Further, a resin composition sheet (B stage sheet) was produced on the PET film in the same manner as in Example 1, except that the above resin composition 2 was used. The resulting resin composition sheet was excellent in flexibility. The minimum melt viscosity of the obtained resin composition sheet was evaluated. The evaluation results are shown in Table 1.

[Example 3]

In Example 1, 9.3 g of 2-butanone (manufactured by Wako Pure Chemical Industries, Ltd.) as a solvent and 5.32 g of the phenol resin obtained in Resin Synthesis Example 1 were added and stirred. Except for using 6.35 g of a bifunctional epoxy resin having a biphenyl skeleton (YL6121H manufactured by Mitsubishi Chemical Corporation) and 0.706 g of a naphthalene-based epoxy resin (HP4032D, manufactured by DIC Co., Ltd.) Resin Composition 3 was prepared, and the viscosity was evaluated. Table 1 shows the particle diameter D50 of each insulating inorganic filler compounded and the weight ratio to the total mass of the insulating inorganic filler.

<Resin Composition Sheet>

A resin composition sheet (B stage sheet) prepared by superposing two sheets was obtained in the same manner as in Example 1, except that the resin composition 3 obtained above was used. The resulting resin composition sheet was excellent in flexibility. The obtained resin composition sheet was evaluated in terms of the lowest melt viscosity and the concave portion occupancy rate in the same manner as in Example 1. [

<Material of metal base board>

In the same manner as in Example 1, except that the resin composition sheet was changed to the resin composition sheet described above to produce a metal base wiring board material. In the obtained metal base plate material, variations in thickness of the thermally conductive insulating layer, peel strength, electrical insulation, and thermal conductivity were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[Example 4]

A varnish-like resin composition 4 was prepared in the same manner as in Example 1 except that 13.7 g of 2-butanone (manufactured by Wako Pure Chemical Industries, Ltd.) was added as a solvent in Example 1, and the viscosity was evaluated. Table 1 shows the particle diameter D50 of each insulating inorganic filler compounded and the weight ratio to the total mass of the insulating inorganic filler.

Subsequently, the resin composition sheet 1 was changed to the resin composition 4 in the same manner as in Example 1 to prepare a resin composition sheet. The resulting resin composition sheet was excellent in flexibility. The obtained resin composition sheet was evaluated in the same manner as in Example 1 for the lowest melt viscosity and concave portion occupancy rate.

In the same manner as in the examples, the metal base sheet material was produced by changing the resin composition sheet to the obtained resin composition sheet, and the variation in the thickness of the thermally conductive insulating layer, the peel strength, the electrical insulating property and the thermal conductivity were evaluated. The evaluation results are shown in Table 1.

[Example 5]

In Example 1, 9.3 g of 2-butanone (manufactured by Wako Pure Chemical Industries, Ltd.) as a solvent and 5.32 g of the phenol resin obtained in Resin Synthesis Example 1 were added and stirred. Except for using 6.35 g of a bifunctional epoxy resin having a biphenyl skeleton (YL6121H manufactured by Mitsubishi Chemical Corporation) and 0.706 g of a naphthalene-based epoxy resin (HP4032D, manufactured by DIC Co., Ltd.) Resin Composition 5 was prepared, and the viscosity was evaluated. Table 1 shows the particle diameter D50 of each insulating inorganic filler compounded and the weight ratio to the total mass of the insulating inorganic filler.

<Resin Composition Sheet>

The resin composition 5 obtained above was applied to a PET film (A53 manufactured by Teijin Dupont Films Co., Ltd.) using a bar coater and dried at 100 占 폚 for 20 minutes. The film thickness after drying was 38 탆. Two sheets of the resin composition sheets after drying were placed facing each other and laminated at 110 DEG C, 0.3 MPa, and a conveying speed of 0.3 m / min using a roll laminator to obtain a resin composition sheet (B stage sheet) having an average thickness of 75 mu m . The resulting resin composition sheet was excellent in flexibility.

<Material of metal base board>

In the same manner as in Example 1, except that the resin composition sheet was changed to the resin composition sheet described above to produce a metal base wiring board material. In the obtained metal base plate material, variations in thickness of the thermally conductive insulating layer, peel strength, electrical insulation, and thermal conductivity were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[Example 6]

In Example 1, 9.3 g of 2-butanone (manufactured by Wako Pure Chemical Industries, Ltd.) as a solvent and 5.32 g of the phenol resin obtained in Resin Synthesis Example 1 were added and stirred. Except for using 6.35 g of a bifunctional epoxy resin having a biphenyl skeleton (YL6121H manufactured by Mitsubishi Chemical Corporation) and 0.706 g of a naphthalene-based epoxy resin (HP4032D, manufactured by DIC Co., Ltd.) Resin Composition 6 was prepared and the viscosity was evaluated. Table 1 shows the particle diameter D50 of each insulating inorganic filler compounded and the weight ratio to the total mass of the insulating inorganic filler.

<Resin Composition Sheet>

The resin composition 6 obtained above was coated on a PET film (A53 manufactured by Teijin Dupont Film Co., Ltd.) using a bar coater and dried at 100 占 폚 for 20 minutes. The film thickness after drying was 63 탆. Two sheets of the resin composition sheets after drying were placed facing each other and laminated at 110 DEG C, 0.3 MPa, and a conveyance speed of 0.3 m / min using a roll laminator to obtain a resin composition sheet (B stage sheet) having an average thickness of 125 mu m . The resulting resin composition sheet was excellent in flexibility.

<Material of metal base board>

In the same manner as in Example 1, except that the resin composition sheet was changed to the resin composition sheet described above to produce a metal base wiring board material. In the obtained metal base plate material, variations in thickness of the thermally conductive insulating layer, peel strength, electrical insulation, and thermal conductivity were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[Example 7]

63 parts of alumina (AL35-63, manufactured by Micron, density: 3.80 g / ml) having a particle diameter D50 of 31 탆, 63 parts of alumina (AX3-32, manufactured by Micron, density: 3.77 g 17 parts of alumina (LS-235, manufactured by Nippon Light Metal Co., Ltd., density: 3.94 g / ml) having a particle diameter D50 of 0.5 mu m was mixed with 18 parts of a spherical alumina (AO802, Manufactured by Dainippon Ink and Chemicals, Inc., density 3.7 g / ml).

90.16 g of the above inorganic filler mixture was weighed, 0.099 g of a silane coupling agent (KBM403, manufactured by Shin-Etsu Chemical Co., Ltd.) and 2-butanone (manufactured by Wako Pure Chemical Industries, Ltd.) as a solvent were placed in a 100- (Manufactured by Kusumoto Chemical Co., Ltd., ED-113) and 2.62 g (solid content) of the phenol resin obtained in Synthesis Example 1 of the resin were added and stirred. , 6.24 g of a bifunctional epoxy resin having a biphenyl skeleton (YL6121H manufactured by Mitsubishi Chemical Corporation), 0.69 g of a naphthalene-based epoxy resin (HP4032D, manufactured by DIC Corporation), 2 g of an imidazole compound (manufactured by Shikoku Kasei Kogyo Co., ) Was added thereto. Further, 120 g of alumina ball having a diameter of 5 mm was charged, and the mixture was stirred at 100 rpm for 12 hours on a ball mill base, and then the alumina balls were separated by filtration to obtain a varnish-type resin composition 7.

The viscosity was evaluated in the same manner as in Example 1. Table 1 shows the particle diameter D50 of each insulating inorganic filler compounded and the weight ratio to the total mass of the insulating inorganic filler.

Subsequently, the resin composition 1 was changed to the resin composition 7 in the same manner as in Example 1 to prepare a resin composition sheet. The resulting resin composition sheet was excellent in flexibility. The obtained resin composition sheet was evaluated in the same manner as in Example 1 for the lowest melt viscosity and the concave portion occupancy rate.

In the same manner as in the examples, the metal base sheet material was produced by changing the resin composition sheet to the obtained resin composition sheet, and the variation in the thickness of the thermally conductive insulating layer, the peel strength, the electrical insulating property and the thermal conductivity were evaluated. The evaluation results are shown in Table 1.

[Example 8]

100 parts by mass of 1- (3-methyl-4-oxiranylmethoxyphenyl) -4- (4-oxiranylmethoxyphenyl) -1-cyclohexene and 100 parts by mass of the phenol resin 1.3 parts by mass of triphenylphosphine, 1.3 parts by mass of KBM-573 (Shin-Etsu Chemical Co., Ltd.), and 1483 parts by mass of alumina powder (α-alumina powder manufactured by Sumitomo Chemical Co., Ltd., Mu] m of alumina having an average particle diameter of 3 [mu] m, and 148 parts by mass of alumina having an average particle diameter of 0.4 [mu] m, and 300 parts by mass of cyclohexanone were mixed, 15.7 parts by mass of the treated silica nanoparticles (product name: Admanano, average particle diameter: 15 nm, NV: 23 mass%) in terms of solid content was added to the resin composition 8 , And the viscosity He said. Table 1 shows the particle diameter D50 of each insulating inorganic filler compounded and the weight ratio to the total mass of the insulating inorganic filler.

<Resin Composition Sheet>

The resin composition was applied on a polyethylene terephthalate (PET) film as an applicator so as to have a thickness of 200 mu m after drying, and then allowed to stand at room temperature for 30 minutes and then dried. After further drying at a temperature of 100 占 폚 for 30 minutes, hot pressing (press temperature of 120 占 폚, vacuum degree of 1 kPa, press pressure of 1 MPa, treatment time of 1 minute) was carried out by a vacuum press to obtain a resin composition sheet (B stage sheet). The obtained resin composition sheet was evaluated for the lowest melt viscosity and the concave portion occupancy rate in the same manner as in Example 1.

<Material of metal base board>

The resin composition sheet of 500 mm x 600 mm from which the PET was peeled was placed on a roughened screen side of a 550 mm x 650 mm copper foil (35 mu m thick, manufactured by Nippon Electric Works Co., Ltd.) and an aluminum substrate (A5052, t) and heated under vacuum at 4 MPa under a vacuum of 3 kPa at 150 DEG C for 5 minutes using a vacuum press. Subsequently, the substrate was heated at 140 占 폚 for 2 hours and at 190 占 폚 for 2 hours under atmospheric pressure to obtain a metal base wiring board material.

In the obtained metal base plate material, variations in thickness of the thermally conductive insulating layer, peel strength, electrical insulation, and thermal conductivity were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

[Comparative Example 1]

A varnish-like resin composition 9 was prepared and the viscosity was evaluated in the same manner as in Example 1 except that 18.2 g of 2-butanone (manufactured by Wako Pure Chemical Industries, Ltd.) as a solvent was added. Table 1 shows the particle diameter D50 of each insulating inorganic filler compounded and the weight ratio to the total mass of the insulating inorganic filler.

Subsequently, the resin composition 1 was changed to the resin composition 9 in the same manner as in Example 1 to prepare a resin composition sheet. The resulting resin composition sheet was excellent in flexibility. The obtained resin composition sheet was evaluated in the same manner as in Example 1 for the lowest melt viscosity and concave portion occupation rate.

In the same manner as in the examples, the metal base sheet material was produced by changing the resin composition sheet to the obtained resin composition sheet, and the variation in the thickness of the thermally conductive insulating layer, the peel strength, the electrical insulating property and the thermal conductivity were evaluated. The evaluation results are shown in Table 1.

[Comparative Example 2]

A varnish-type resin composition 10 was prepared in the same manner as in Example 2 except that 19.3 g of 2-butanone (manufactured by Wako Pure Chemical Industries, Ltd.) was added as a solvent in Example 2, and the viscosity was evaluated. Table 1 shows the particle diameter D50 of each insulating inorganic filler compounded and the weight ratio to the total mass of the insulating inorganic filler.

Subsequently, the resin composition sheet 1 was changed to the resin composition 10 in the same manner as in Example 1 to prepare a resin composition sheet. The resulting resin composition sheet was excellent in flexibility. The obtained resin composition sheet was evaluated in the same manner as in Example 1 for the lowest melt viscosity and the concave portion occupancy rate.

In the same manner as in the examples, the metal base sheet material was produced by changing the resin composition sheet to the obtained resin composition sheet, and the variation in the thickness of the thermally conductive insulating layer, the peel strength, the electrical insulating property and the thermal conductivity were evaluated. The evaluation results are shown in Table 1.

From Table 1, it can be seen that the cured products of the resin composition sheets of Examples 1 to 8 are superior in thermal conductivity and electrical insulating properties to those of Comparative Examples 1 and 2.

The resin composition sheet according to the present invention can be used even if a resin composition sheet other than the resin used in the above-mentioned embodiment is used as the thermosetting resin, and if the resin composition sheet occupies a concave portion having a maximum depth of 0.5 탆 or more at a surface area of 4% Effect can be obtained.

Claims (12)

An epoxy resin, a phenol resin, and an insulating inorganic filler,
The occupancy rate of the concave portion having the maximum depth of 0.5 占 퐉 or more on the surface is 4% or less in area ratio,
Wherein the phenolic resin has a structural unit represented by the following general formula (I)
And 5% by mass to 80% by mass of a monomer which is a phenolic compound constituting the phenol resin.

Wherein R ¹ represents an alkyl group, an aryl group or an aralkyl group, R ² and R ³ each independently represent a hydrogen atom, an alkyl group, an aryl group or an aralkyl group, m represents an integer of 0 to 2, And n represents an integer of 1 to 10.] The method according to claim 1,
And a minimum melt viscosity at 20 占 폚 to 200 占 폚 of 10 to 1000 Pa 占 퐏. The method according to claim 1,
Wherein the insulating inorganic filler is contained in an amount of 40 vol% or more and 82 vol% or less. The method according to claim 1,
Wherein the insulating inorganic filler is at least one kind of filler selected from the group consisting of aluminum oxide, magnesium oxide, boron nitride, aluminum nitride, silicon nitride, silicon carbide, and aluminum fluoride filler. The method according to claim 1,
A resin composition containing the epoxy resin, the phenol resin, and the insulating inorganic filler,
Wherein the resin composition has a viscosity of 1000 mPa s to 10000 mPa 이하,
A resin composition sheet formed by applying the resin composition on a support substrate. A minimum melt viscosity at 20 ° C to 200 ° C of 10 Pa · s to 1000 Pa · s,
The occupancy rate of the concave portion having the maximum depth of 0.5 占 퐉 or more on the surface is 4% or less in area ratio,
A resin composition comprising a phenol resin having a structural unit represented by the following general formula (I)
And 5% by mass to 80% by mass of a monomer which is a phenolic compound constituting the phenol resin.

Wherein R ¹ represents an alkyl group, an aryl group or an aralkyl group, R ² and R ³ each independently represent a hydrogen atom, an alkyl group, an aryl group or an aralkyl group, m represents an integer of 0 to 2, And n represents an integer of 1 to 10.] The method according to claim 1,
Wherein the average thickness of the resin composition sheet is 20 占 퐉 or more and 500 占 퐉 or less. A resin composition sheet according to any one of claims 1 to 7, and a resin composition sheet to which a metal foil having a metal foil is attached. Metal foil,
A metal substrate,
A metal base wiring board material having a thermally conductive insulating layer as a cured product of the resin composition sheet according to any one of claims 1 to 7 between the metal foil and the metal substrate. A wiring layer,
A metal substrate,
A metal base wiring board having a thermally conductive insulating layer as a cured product of the resin composition sheet according to any one of claims 1 to 7, between the wiring layer and the metal substrate. An LED light source member formed using the resin composition sheet according to any one of claims 1 to 7. delete

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