WO2014133189A1

WO2014133189A1 - Laminate and method of producing same

Info

Publication number: WO2014133189A1
Application number: PCT/JP2014/055526
Authority: WO
Inventors: 剛司近藤; 亮宮越
Original assignee: 住友化学株式会社
Priority date: 2013-02-28
Filing date: 2014-02-26
Publication date: 2014-09-04
Also published as: JPWO2014133189A1; CN105075404A; CN105075404B; TWI622492B; TW201437009A; KR20150122720A; JP6385917B2

Abstract

Provided is a metal-base circuit board superior in stamping workability and bending workability. The present invention is a laminate having a metal plate obtained by a rolling method, an insulating layer provided upon the metal plate and including resin, and a metal foil provided upon the insulating layer, the metal plate being a metal plate such that, on a surface in contact with the insulating layer, ten-point mean roughness Rz (MD) in a direction of rolling and ten-point mean roughness Rz (TD) in a direction perpendicular to the direction of rolling are independently 4 to 20 μm, and the ratio of the Rz (TD) with respect to the Rz (MD) (Rz (TD)/Rz (MD)) is less than or equal to 1.5.

Description

Laminate and manufacturing method thereof

The present invention relates to a laminate and a method for manufacturing the same.

In recent years, with the miniaturization, high performance and high power of electric / electronic devices, circuit boards are required to easily dissipate heat generated from mounted elements, that is, to have excellent heat dissipation. . As a circuit board capable of meeting this requirement, a metal base circuit board having a metal plate, an insulating layer provided thereon, and a circuit pattern provided thereon has been studied. The metal base circuit board is obtained by patterning a metal foil from a laminated board having a metal plate, an insulating layer provided thereon, and a metal foil provided thereon (for example, (See Patent Documents 1 to 8).

Japanese Patent Laid-Open No. 5-167212 International Publication No. 2010/117033 JP 2011-32316 A JP 2011-77270 A JP 2011-181833 A JP 2011-219749 A JP 2011-249606 A JP 2012-4323 A

In the conventional metal base circuit board, the insulating layer may be easily chipped when punching. Further, when bending, the insulating layer may be easily peeled off from the metal plate. Therefore, an object of the present invention is to provide a laminate having excellent punching workability and bending workability, and to provide a metal base circuit board having excellent punching workability and bending workability.

In order to achieve the above object, the present invention provides a laminate comprising a metal plate obtained by a rolling method, an insulating layer provided on the metal plate and containing a resin, and a metal foil provided on the insulating layer. The metal plate has a ten-point average roughness Rz (MD) in a rolling direction and a ten-point average roughness Rz (TD) in a direction perpendicular to the rolling direction on a surface in contact with the insulating layer, respectively. Independently, there is provided a laminated plate which is a metal plate having a size of 4 to 20 μm and a ratio of Rz (TD) to Rz (MD) (Rz (TD) / Rz (MD)) being 1.5 or less. Moreover, according to this invention, it is a manufacturing method of the said laminated board, Comprising: The laminated board which has the process of obtaining the said metal plate by roughening the at least one surface of the raw material metal plate obtained by the rolling method Is also provided.

The laminate of the present invention is excellent in punching workability and bending workability, and is excellent in heat dissipation.

The laminated board of this invention is a laminated board which has a metal plate, the insulating layer provided on it, and the metal foil provided on it.
In the present invention, the metal plate is a metal plate obtained by a rolling method, and at least one of the surfaces has independent 10-point average roughness in the rolling direction and 10-point average roughness in the direction perpendicular to the rolling direction. The ratio of the ten-point average roughness in the direction perpendicular to the rolling direction to the ten-point average roughness in the rolling direction (ten-point average roughness in the direction perpendicular to the rolling direction / tenth in the rolling direction). A metal plate having a rough surface with a point average roughness of 1.5 or less is used, and lamination is performed so that the rough surface is in contact with the insulating layer. That is, on the surface in contact with the insulating layer of the metal plate, when the ten-point average roughness in the rolling direction is Rz (MD) and the ten-point average roughness in the direction perpendicular to the rolling direction is Rz (TD), Rz (TD) MD) and Rz (TD) are each independently 4 to 20 μm, and Rz (TD) / Rz (MD) is 1.5 or less. Thereby, the laminated board which is excellent in punch workability and bending workability, and is excellent also in heat dissipation can be obtained.
The other surface of the metal plate, that is, the surface opposite to the surface in contact with the insulating layer may be a mirror surface or a rough surface, and if it is a rough surface, the surface in contact with the insulating layer Similarly, the ten-point average roughness in the rolling direction and the ten-point average roughness in the direction perpendicular to the rolling direction are each independently 4 to 20 μm, and the direction perpendicular to the rolling direction with respect to the ten-point average roughness in the rolling direction The ten-point average roughness ratio (ten-point average roughness in the direction perpendicular to the rolling direction / ten-point average roughness in the rolling direction) of 1.5 or less may be a rough surface. It may be a rough surface.
Rz (MD) and Rz (TD) are preferably each independently 4 to 10 μm, and Rz (TD) / Rz (MD) is preferably 1.2 or less. Punching workability and bending workability are further improved.
The ten-point average roughness of the surface of the metal plate is measured according to JIS B0601: 1994.
Such a metal plate can be obtained by roughening at least one surface of the raw metal plate obtained by the rolling method uniformly and appropriately so as to be the predetermined rough surface. The roughening may be performed on both surfaces or only on one surface, but is preferably performed on both surfaces because the punching workability and bending workability of the laminate are further improved.
The roughening may be performed by a dry surface roughening method such as blasting or polishing, or by a wet surface roughening method such as anodizing or etching. Among these, it is preferable to roughen the surface by blasting, whereby the punching workability and bending workability of the laminate are further improved. The blast treatment is a method of roughening the metal plate by spraying an abrasive such as alumina, steel grains, sand, glass beads or the like onto the metal plate by air pressure or centrifugal force.
Examples of the material of the metal plate include aluminum, iron, and copper, and may be an alloy such as an aluminum alloy or stainless steel. Of these, copper and aluminum alloys are preferred. The metal plate may contain a nonmetal such as carbon, and may contain, for example, aluminum combined with carbon. The metal plate preferably has a high thermal conductivity, and the thermal conductivity is preferably 60 W · m ⁻¹ · K ⁻¹ or more.
The thickness of the metal plate is usually 0.2 mm or more, preferably 0.5 mm or more, and this facilitates improving the heat dissipation of the laminated plate. Moreover, the thickness of a metal plate is 5 mm or less normally, Preferably it is 1.5 mm or less, and it becomes easy to improve the punching workability and bending workability of a laminated board by this. The metal plate may have flexibility or may not have flexibility. The metal plate may have a single layer structure or a multilayer structure.
The insulating layer is provided on the metal plate and contains a resin. The resin plays a role as an adhesive for bonding the metal plate and the metal foil and a function of flattening the surface of the insulating layer.
Examples of the resin include thermoplastic resins such as polypropylene, polyamide, polyesters other than liquid crystal polyester, liquid crystal polyester, polyphenylene sulfide, polyether ketone, polycarbonate, polyether sulfone, polyphenylene ether, polyether imide; and phenol resin, epoxy resin And thermosetting resins such as polyimide resins and cyanate resins, and two or more of them may be used. Among these, liquid crystal polyester is preferable because of its high heat resistance and low dielectric loss.
The liquid crystalline polyester is a polyester that exhibits liquid crystallinity in a molten state, and is preferably a liquid crystalline polyester that melts at a temperature of 450 ° C. or lower. The liquid crystal polyester may be a liquid crystal polyester amide, a liquid crystal polyester ether, a liquid crystal polyester carbonate, or a liquid crystal polyester imide. The liquid crystal polyester is preferably a wholly aromatic liquid crystal polyester using only an aromatic compound as a raw material monomer.
A typical example of the liquid crystal polyester is polymerization (polycondensation) of an aromatic hydroxycarboxylic acid, an aromatic dicarboxylic acid, and at least one compound selected from the group consisting of an aromatic diol, an aromatic hydroxyamine, and an aromatic diamine. At least one selected from the group consisting of aromatic dicarboxylic acids and aromatic diols, aromatic hydroxyamines and aromatic diamines. Examples thereof include a liquid crystal polyester obtained by polymerizing a compound and a liquid crystal polyester obtained by polymerizing a polyester such as polyethylene terephthalate and an aromatic hydroxycarboxylic acid. Here, the aromatic hydroxycarboxylic acid, the aromatic dicarboxylic acid, the aromatic diol, the aromatic hydroxyamine, and the aromatic diamine are each independently replaced with a part or all of the polymerizable derivative. Also good.
Examples of polymerizable derivatives of a compound having a carboxyl group such as aromatic hydroxycarboxylic acid and aromatic dicarboxylic acid include derivatives (esters) obtained by converting a carboxyl group into an alkoxycarbonyl group or an aryloxycarbonyl group, carboxyl Derivatives obtained by converting a group into a haloformyl group (acid halide) and derivatives obtained by converting a carboxyl group into an acyloxycarbonyl group (an acid anhydride) are included. Examples of polymerizable derivatives of hydroxyl group-containing compounds such as aromatic hydroxycarboxylic acids, aromatic diols and aromatic hydroxyamines include derivatives obtained by acylating hydroxyl groups and converting them into acyloxyl groups (acylated products) ). Examples of polymerizable derivatives of amino group-containing compounds such as aromatic hydroxyamines and aromatic diamines include derivatives (acylated products) obtained by acylating amino groups and converting them to acylamino groups.
The liquid crystalline polyester preferably has a repeating unit represented by the following formula (1) (hereinafter sometimes referred to as “repeating unit (1)”), and the repeating unit (1) and the following formula (2) A repeating unit represented (hereinafter sometimes referred to as “repeating unit (2)”) and a repeating unit represented by the following formula (3) (hereinafter sometimes referred to as “repeating unit (3)”). It is more preferable to have.
(1) —O—Ar ¹ —CO—
(2) —CO—Ar ² —CO—
(3) ^-X-Ar 3 -Y-
(Ar ¹ represents a phenylene group, a naphthylene group, or a biphenylylene group. Ar ² and Ar ³ each independently represent a phenylene group, a naphthylene group, a biphenylylene group, or a group represented by the following formula (4). X And Y each independently represents an oxygen atom or an imino group (—NH—), and each hydrogen atom in the group represented by Ar ¹ , Ar ² or Ar ³ is independently a halogen atom or an alkyl group. Alternatively, it may be substituted with an aryl group.)
(4) -Ar ⁴ -Z-Ar ^5-
(Ar ⁴ and Ar ⁵ each independently represent a phenylene group or a naphthylene group. Z represents an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, or an alkylidene group.)
As said halogen atom, a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom are mentioned. Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, s-butyl group, t-butyl group, n-hexyl group, 2-ethylhexyl group, Examples thereof include n-octyl group and n-decyl group, and the carbon number thereof is usually 1-10. Examples of the aryl group include a phenyl group, an o-tolyl group, an m-tolyl group, a p-tolyl group, a 1-naphthyl group, and a 2-naphthyl group, and the number of carbon atoms is usually 6 to 20. . When the hydrogen atom is substituted with these groups, the number is usually 2 or less for each of the groups represented by Ar ¹ , Ar ² or Ar ³ , and preferably 1 It is as follows.
Examples of the alkylidene group include a methylene group, an ethylidene group, an isopropylidene group, an n-butylidene group, and a 2-ethylhexylidene group, and the number of carbon atoms is usually 1 to 10.
The repeating unit (1) is a repeating unit derived from a predetermined aromatic hydroxycarboxylic acid. The repeating unit (1) includes a repeating unit (1) in which Ar ¹ is a p-phenylene group (a repeating unit derived from p-hydroxybenzoic acid), and a repeating unit in which Ar ¹ is a 2,6-naphthylene group ( 1) (Repeating unit derived from 6-hydroxy-2-naphthoic acid) is preferred.
The repeating unit (2) is a repeating unit derived from a predetermined aromatic dicarboxylic acid. As the repeating unit (2), a repeating unit (2) in which Ar ² is a p-phenylene group (a repeating unit derived from terephthalic acid), a repeating unit (2) in which Ar ² is an m-phenylene group (in isophthalic acid) Derived repeating unit), Ar ² is a 2,6-naphthylene group repeating unit (2) (a repeating unit derived from 2,6-naphthalenedicarboxylic acid), and Ar ² is a diphenyl ether-4,4′-diyl group. The repeating unit (2) (repeating unit derived from diphenyl ether-4,4′-dicarboxylic acid) is preferred.
The repeating unit (3) is a repeating unit derived from a predetermined aromatic diol, aromatic hydroxylamine or aromatic diamine. As the repeating unit (3), a repeating unit (3) in which Ar ³ is a p-phenylene group (a repeating unit derived from hydroquinone, p-aminophenol or p-phenylenediamine) is preferable.
The content of the repeating unit (1) is the total amount of all repeating units (the mass equivalent amount of each repeating unit (moles by dividing the mass of each repeating unit constituting the liquid crystal polyester by the formula amount of each repeating unit). Is usually 30 mol% or more, preferably 30 to 80 mol%, more preferably 30 to 60 mol%, still more preferably 30 to 40 mol%. The content of the repeating unit (2) is usually 35 mol% or less, preferably 10 to 35 mol%, more preferably 20 to 35 mol%, still more preferably 30 to 35 mol, based on the total amount of all repeating units. %. The content of the repeating unit (3) is usually 35 mol% or less, preferably 10 to 35 mol%, more preferably 20 to 35 mol%, still more preferably 30 to 35 mol, based on the total amount of all repeating units. %. As the content of the repeating unit (1) is increased, the heat resistance, strength and rigidity are likely to be improved. However, if the content is too large, the solubility in a solvent is likely to be lowered.
The ratio between the content of the repeating unit (2) and the content of the repeating unit (3) is expressed as [content of repeating unit (2)] / [content of repeating unit (3)] (mol / mol). In general, it is 0.9 / 1 to 1 / 0.9, preferably 0.95 / 1 to 1 / 0.95, and more preferably 0.98 / 1 to 1 / 0.98.
The liquid crystal polyester may have two or more repeating units (1) to (3) independently. The liquid crystalline polyester may have repeating units other than the repeating units (1) to (3), and the content thereof is usually 10 mol% or less, preferably with respect to the total amount of all repeating units. 5 mol% or less.
The liquid crystalline polyester has a repeating unit (3) in which X and / or Y is an imino group as the repeating unit (3), that is, a repeating unit derived from a predetermined aromatic hydroxylamine and / or an aromatic diamine. Having the repeating unit derived from is preferable because it has excellent solubility in a solvent, and it is more preferable that the repeating unit (3) has only the repeating unit (3) in which X and / or Y is an imino group.
The liquid crystal polyester is preferably produced by melt polymerization of raw material monomers corresponding to the repeating units constituting the liquid crystal polyester, and solid-phase polymerization of the obtained polymer (prepolymer). Thereby, high molecular weight liquid crystal polyester having high heat resistance, strength and rigidity can be produced with good operability. Melt polymerization may be carried out in the presence of a catalyst. Examples of this catalyst include metal compounds such as magnesium acetate, stannous acetate, tetrabutyl titanate, lead acetate, sodium acetate, potassium acetate, and antimony trioxide, And nitrogen-containing heterocyclic compounds such as 4- (dimethylamino) pyridine and 1-methylimidazole, and nitrogen-containing heterocyclic compounds are preferably used.
The flow starting temperature of the liquid crystalline polyester is usually 250 ° C. or higher, preferably 250 ° C. to 350 ° C., more preferably 260 ° C. to 330 ° C. As the flow start temperature is higher, the heat resistance, strength, and rigidity are more likely to be improved. However, if the flow start temperature is too high, the solubility in a solvent tends to be low, and the viscosity of the liquid composition tends to be high.
The flow start temperature is also called flow temperature or flow temperature, and the temperature is raised at a rate of 4 ° C./min under a load of 9.8 MPa (100 kg / cm ² ) using a capillary rheometer while liquid crystal polyester is used. Is a temperature showing a viscosity of 4800 Pa · s (48000 poise) when extruded from a nozzle having an inner diameter of 1 mm and a length of 10 mm, and is a measure of the molecular weight of the liquid crystal polyester (Naoki Koide, “Liquid Crystal Polymer— "Synthesis / Molding / Application-", CMC Co., Ltd., June 5, 1987, p. 95).
The proportion of the resin in the insulating layer is preferably 30 to 60% by volume, more preferably 35 to 55% by volume. If this ratio is too small, the adhesion between the insulating layer and the metal plate or the metal foil is lowered, or the surface flatness of the insulating layer is lowered. Moreover, if this ratio is too large, the heat dissipation of the laminate will be reduced.
The insulating layer preferably further contains at least one inorganic filler selected from the group consisting of aluminum oxide, silicon oxide, boron nitride, and aluminum nitride. By including the inorganic filler in the insulating layer, the heat dissipation of the laminate is improved.
As at least a part of the inorganic filler, a surface-treated inorganic filler may be used in order to improve adhesion with a resin and dispersibility in a liquid composition described later. Examples of surface treatment agents that can be used for this surface treatment include silane coupling agents, titanium coupling agents, aluminum coupling agents, zirconium coupling agents, long chain fatty acids, isocyanate compounds, and epoxy groups and methoxysilyl groups. And polymers having an amino group or a hydroxyl group.
The proportion of the inorganic filler in the insulating layer is preferably 40 to 70% by volume, more preferably 45 to 65% by volume. If this ratio is too small, the heat dissipation of the laminate will decrease. On the other hand, if this ratio is too large, the punching workability and bending workability of the laminate will be reduced.
The insulating layer may contain components other than the resin and the inorganic filler, for example, organic fillers and additives. However, the proportion of the insulating layer in the insulating layer is usually 0 to 10 in total when plural types are included. % By volume. Examples of organic fillers include cured epoxy resins, crosslinked benzoguanamine resins, and crosslinked acrylic resins. Examples of additives include leveling agents, antifoaming agents, antioxidants, ultraviolet absorbers, flame retardants, and colorants.
The insulating layer may contain inorganic fillers other than aluminum oxide, silicon oxide, boron nitride, and aluminum nitride as inorganic fillers, but the proportion of the inorganic fillers is plural. In some cases, the total amount is usually 0 to 10% by volume.
The metal foil is provided on the insulating layer and faces the metal plate with the insulating layer interposed therebetween. Examples of the metal foil material include copper and aluminum, and may be an alloy. The thickness of the metal foil is usually 10 to 500 μm.
Production of the laminated board of the present invention is as follows. (A): First, a laminated intermediate of a metal foil and an insulating layer is produced, and then this laminated intermediate is used as a roughened surface of the metal plate with the insulating layer surface as a bonding surface. (B): First, using the rough surface of the metal plate as the bonding surface, a laminated intermediate of the metal plate and the insulating layer is manufactured, and then this The laminated intermediate may be performed by bonding the metal layer to the metal foil by thermocompression bonding using the insulating layer surface as a bonding surface. (C): First, an insulating film to be an insulating layer is manufactured, and then this The insulating film may be formed by sandwiching the rough surface of the metal plate between the metal plate and the metal foil and bonding them by thermocompression bonding or the like.
The insulating layer is preferably formed by applying a liquid composition containing a resin and a solvent to a support and drying (solvent removal) the resulting coating film. In that case, the laminated intermediate body of the metal foil and insulating layer in said (A) can be manufactured by using metal foil as a support body. Moreover, the laminated intermediate body of the metal plate and insulating layer in said (B) can be manufactured by using a metal plate as a support body. In addition, when using a support other than the metal foil and the metal plate as the support, for example, a resin film such as a polyester film, a polypropylene film, a fluororesin film, a nylon film, or a polymethylpentene film, the support was formed on the support. By transferring the insulating layer from the support to the metal foil by thermocompression bonding or the like, a laminated intermediate of the metal foil and the insulating layer in (A) can be produced, and the insulating layer formed on the support is By transferring from the support to the metal plate by thermocompression bonding or the like, a laminated intermediate of the metal plate and the insulating layer in (B) can be produced, and the insulating layer formed on the support is removed from the support. By peeling off, the insulating film in (C) can be produced.
As the solvent, a solvent that can dissolve the resin to be used, specifically, a solvent that can be dissolved at a concentration of 1% by mass or more at 50 ° C. ([resin] / [resin + solvent]) is appropriately selected and used. .
Examples of solvents include halogenated hydrocarbons such as dichloromethane, chloroform, 1,2-dichloroethane, 1,1,2,2-tetrachloroethane, o-dichlorobenzene; p-chlorophenol, pentachlorophenol, pentafluorophenol Halogenated phenols such as diethyl ether, tetrahydrofuran, 1,4-dioxane, etc .; ketones such as acetone and cyclohexanone; esters such as ethyl acetate and γ-butyrolactone; carbonates such as ethylene carbonate and propylene carbonate; amines such as triethylamine Nitrogen-containing heteroaromatic compounds such as pyridine; nitriles such as acetonitrile and succinonitrile; amides such as N, N-dimethylformamide, N, N-dimethylacetamide and N-methylpyrrolidone; Examples include urea compounds such as tramethylurea; nitro compounds such as nitromethane and nitrobenzene; sulfur compounds such as dimethyl sulfoxide and sulfolane; and phosphorus compounds such as hexamethylphosphoric acid amide and tri-n-butylphosphoric acid. May be used.
As the solvent, since it is low in corrosivity and easy to handle, an aprotic compound, particularly a solvent mainly comprising an aprotic compound having no halogen atom, is preferred, and the proportion of the aprotic compound in the entire solvent is: The content is preferably 50 to 100% by mass, more preferably 70 to 100% by mass, and still more preferably 90 to 100% by mass. As the aprotic compound, it is preferable to use an amide such as N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone and the like because the resin is easily dissolved.
The solvent is preferably a solvent mainly composed of a compound having a dipole moment of 3 to 5 because the resin is easily dissolved, and the ratio of the compound having a dipole moment of 3 to 5 in the entire solvent is Preferably, it is 50 to 100% by mass, more preferably 70 to 100% by mass, and still more preferably 90 to 100% by mass, and a compound having a dipole moment of 3 to 5 is used as the aprotic compound. preferable.
Moreover, as a solvent, since it is easy to remove, the solvent which has as a main component the compound whose boiling point in 1 atmosphere is 220 degrees C or less is preferable, and the ratio of the compound whose boiling point in 1 atmosphere in the whole solvent is 220 degrees C or less Is preferably 50 to 100% by mass, more preferably 70 to 100% by mass, and still more preferably 90 to 100% by mass. As the aprotic compound, a compound having a boiling point at 1 atm of 220 ° C. or less is used. It is preferable.
The content of the resin in the liquid composition is usually 5 to 60% by mass, preferably 10 to 50% by mass, more preferably 15 to 45% by mass with respect to the total amount of the resin and the solvent, and a desired viscosity. It adjusts suitably so that the liquid composition of this may be obtained.
The liquid composition is preferably prepared by dispersing the inorganic filler and, if necessary, other components in a solution obtained by dissolving the resin and other components, if necessary, in a solvent. The inorganic filler may be dispersed in the solution while being pulverized by a ball mill, three rolls, a centrifugal stirrer, a bead mill or the like.
Examples of the method of applying the liquid composition to the support include a roll coating method, a bar coating method, a screen printing method, a die coater method, and a comma coater method. Plate type).
The coating film is preferably dried by evaporating the solvent from the coating film. When using a support other than metal foil and metal plate as the support, drying the coating film formed on the support, and transferring the resulting dried film from the support to the metal foil or metal plate by thermocompression bonding or the like Is preferably performed so that a part of the solvent remains in the dry film. In this case, the amount of solvent in the dry film is preferably 1 to 25% by mass. The drying temperature is usually 50 to 180 ° C, preferably 80 to 150 ° C.
The dry film formed on the support or the dry film transferred to the metal foil or metal plate is preferably heat-treated when a thermoplastic resin is used as the resin, thereby adjusting its molecular weight and crystallinity. Therefore, an insulating layer having excellent adhesion and thermal conductivity can be obtained. The heat treatment is usually performed at 250 to 350 ° C., preferably 270 to 320 ° C. in an inert gas atmosphere such as nitrogen gas.
When a laminated intermediate body of a metal foil and an insulating layer is thus obtained, as shown in (A), the laminated intermediate body is bonded to the rough surface of the metal plate by thermocompression bonding or the like with the insulating layer surface as the bonding surface. Thereby, the laminated board of this invention is obtained. Moreover, when the laminated surface of the metal plate and the insulating layer was obtained with the rough surface of the metal plate as the bonding surface, as described in (B), the laminated intermediate was used with the insulating layer surface as the bonding surface, The laminated sheet of the present invention can be obtained by laminating with a metal foil by thermocompression bonding or the like. Moreover, when the insulating layer formed on the support is peeled from the support to obtain an insulating film, as described in (C) above, the insulating film is used as a metal plate with the rough surface of the metal plate as a bonding surface. The laminate of the present invention can be obtained by sandwiching between metal foils and bonding them together by thermocompression bonding or the like.
A metal base circuit board is formed by patterning the metal foil from the laminate thus obtained, forming a circuit pattern, and performing a punching process such as a cutting process or a drilling process or a bending process as necessary. Is obtained. The patterning of the metal foil is performed, for example, by forming a mask pattern on the metal foil and removing the exposed portion of the metal foil by etching.

[Measurement of flow start temperature of liquid crystalline polyester]
Using a flow tester (“CFT-500 type” manufactured by Shimadzu Corporation), about 2 g of liquid crystalline polyester was filled into a cylinder attached with a die having a nozzle having an inner diameter of 1 mm and a length of 10 mm, and 9.8 MPa (100 kg). The liquid crystal polyester was melted while being heated at a rate of 4 ° C./min under a load of / cm ² ), extruded from a nozzle, and a temperature showing a viscosity of 4800 Pa · s (48000 P) was measured.
[Measurement of viscosity of liquid crystal polyester solution]
Using a B-type viscometer (“TVL-20” from Toki Sangyo Co., Ltd.) The measurement was performed at a rotation speed of 20 rpm using 21 rotors.
(Measurement of ten-point average roughness of metal plate surface)
Using a surface roughness measuring device (KLA Tencor Corporation, calculation standard JIS B0601-1994), in accordance with JIS B0601: 1994, measurement speed: 5 μm / second, evaluation length: 1.0 mm Measured with
[Metal plate]
Thickness of the metal plate obtained by the rolling method is a mirror surface (ten-point average roughness in the rolling direction: 1.2 μm, ten-point average roughness in the direction perpendicular to the rolling direction: 2.4 μm) A metal plate obtained by roughening one surface of a 0 mm aluminum alloy plate by blasting, wherein one surface is a rough surface having the ten-point average roughness shown in Table 1, and the other surface Metal plates (1) to (4) having a thickness of 1.0 mm and having a mirror surface were used. Moreover, the said aluminum alloy plate was used as a metal plate (5) as it was.

[Punching workability]
After punching the laminated plate with a press machine (“80 ton press” from Aida Engineering Co., Ltd.) under the conditions of a holder pressure of 20 kN, a knockout force of 59 kN, and a press speed of 60 SPN using a total punching die for an aluminum plate The presence or absence of chipping of the insulating layer on the cut surface was confirmed with an optical microscope.
[Bending workability]
The metal foil of the laminated plate cut to a size of 10 mm × 30 mm was removed by etching, and the resulting laminate of the metal plate and the insulating layer was 180 ° so that the bent portion had a diameter of 15 mm with the insulating layer as the outside. After bending, the presence or absence of peeling of the insulating layer from the metal plate was visually observed.
[Heat dissipation of insulation layer]
The metal foil of the laminated plate cut to a size of 30 mm × 40 mm was partially removed by etching to form a land of 14 mm × 10 mm. A transistor ("C2233" manufactured by Toshiba Corporation) is attached to this land using solder, and the obtained laminated plate with the transistor is attached to the water cooling device, and the metal plate is connected to the cooling surface of the water cooling device via the silicone grease layer. Set to face each other. Next, the power P of 30 W is supplied to the transistor, the temperature T1 of the transistor and the temperature T2 of the cooling surface of the water cooling device are measured, and the value of the ratio T1-T2 between the temperature T1 and the temperature T2 with respect to the power P (T1-T2) / P was defined as thermal resistance.
Examples 1 and 2 and Comparative Examples 1 to 3
[Production of liquid crystalline polyester]
In a reactor equipped with a stirrer, a torque meter, a nitrogen gas introduction tube, a thermometer and a reflux condenser, 1976 g (10.5 mol) of 6-hydroxy-2-naphthoic acid and 1474 g (9.75 mol) of 4-hydroxyacetanilide were added. ), 1620 g (9.75 mol) of isophthalic acid and 2374 g (23.25 mol) of acetic anhydride, and after replacing the gas in the reactor with nitrogen gas, the mixture was stirred at room temperature to 150 ° C. under a nitrogen gas stream. The mixture was heated up to 15 minutes and refluxed at 150 ° C. for 3 hours. Next, while distilling off by-product acetic acid and unreacted acetic anhydride, the temperature was raised from 150 ° C. to 300 ° C. over 2 hours and 50 minutes, held at 300 ° C. for 1 hour, and then the contents were taken out from the reactor, Cooled to room temperature. The obtained solid was pulverized with a pulverizer to obtain a powdery prepolymer. The flow initiation temperature of this prepolymer was 235 ° C. Next, the prepolymer was heated from room temperature to 223 ° C. over 6 hours under a nitrogen atmosphere and held at 223 ° C. for 3 hours to solid-phase polymerize, and then cooled to powdery liquid crystalline polyester Got. The liquid crystal polyester had a flow start temperature of 270 ° C.
[Preparation of liquid crystal polyester solution]
2200 g of liquid crystal polyester was added to 7800 g of N, N-dimethylacetamide and heated at 100 ° C. for 2 hours to obtain a liquid crystal polyester solution. The viscosity of this solution was 400 cP.
(Preparation of liquid composition)
Boron nitride and aluminum oxide were added to the liquid crystal polyester solution, and the mixture was stirred for 5 minutes with a centrifugal stirring deaerator to obtain a liquid composition. The ratio between the liquid crystal polyester and the boron nitride and aluminum oxide, from each of the specific gravity (liquid crystal polyester 1.37 g / cm ^3, aluminum oxide 3.98 g / cm ^3, boron nitride 2.28 g / cm ^3), the liquid crystal Adjustments were made on a mass basis so as to be 50% by volume of polyester, 25% by volume of aluminum oxide, and 25% by volume of boron nitride.
[Production of laminated intermediate of copper foil and insulating layer]
The liquid composition was applied to a polyester film having a thickness of 100 μm so that the thickness of the coating film was about 90 μm, and then dried at 100 ° C. for 20 minutes. The obtained intermediate laminate of the polyester film and the dried film is passed between a pair of hot rolls heated to 150 ° C., with the copper foil having a thickness of 35 μm overlapped so that the dried film is in contact with the copper foil. The dry film and the copper foil were thermocompression bonded. Next, the polyester film was peeled off, and the resulting laminated intermediate of the copper foil and the dried film was heat treated at 290 ° C. for 3 hours to obtain a laminated intermediate of the copper foil and the insulating layer.
[Manufacture of laminates]
The laminated intermediate body of copper foil and an insulating layer was piled up with the metal plate. At that time, when the metal plate (1) to (4) is used as the metal plate, the rough surface of the metal plate is brought into contact with the insulating layer, and when the metal plate (5) is used as the metal plate, the metal plate One side of the plate was in contact with the insulating layer. Next, heat treatment was performed at 340 ° C. for 20 minutes while applying a pressure of 20 MPa, and the insulating layer and the metal plate were thermocompression bonded. The obtained laminated plate was evaluated for punching workability and bending workability, and the thermal resistance of the insulating layer was measured and shown in Table 2.

Claims

A metal plate obtained by a rolling method, an insulating layer provided on the metal plate and including a resin, and a metal foil provided on the insulating layer, wherein the metal plate is The ten-point average roughness Rz (MD) in the rolling direction and the ten-point average roughness Rz (TD) in the direction perpendicular to the rolling direction on the surface in contact with the insulating layer are each independently 4 to 20 μm, and the Rz The laminated board which is a metal plate whose ratio (Rz (TD) / Rz (MD)) of said Rz (TD) with respect to (MD) is 1.5 or less.
The laminate according to claim 1, wherein the resin is liquid crystal polyester.
The liquid crystalline polyester is a liquid crystalline polyester having a repeating unit represented by the following formula (1), a repeating unit represented by the following formula (2), and a repeating unit represented by the following formula (3). Item 3. The laminated sheet according to item 2.
(1) —O—Ar 1 —CO—
(2) —CO—Ar 2 —CO—
(3) -X-Ar 3 -Y-
(Ar 1 represents a phenylene group, a naphthylene group, or a biphenylylene group. Ar 2 and Ar 3 each independently represent a phenylene group, a naphthylene group, a biphenylylene group, or a group represented by the following formula (4). X And Y each independently represents an oxygen atom or an imino group, and each hydrogen atom in the group represented by Ar 1 , Ar 2 or Ar 3 is independently substituted with a halogen atom, an alkyl group or an aryl group. May be.)
(4) -Ar 4 -Z-Ar 5-
(Ar 4 and Ar 5 each independently represent a phenylene group or a naphthylene group. Z represents an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, or an alkylidene group.)
The liquid crystalline polyester has a repeating unit represented by the formula (1) of 30 to 80 mol% and a repeating unit represented by the formula (2) of 10 with respect to the total amount of all the repeating units constituting the liquid crystalline polyester. 4. The laminate according to claim 3, which is a liquid crystal polyester having 35 to 35 mol% and 10 to 35 mol% of the repeating unit represented by the formula (3).
The laminate according to claim 3 or 4, wherein X and / or Y are each an imino group.
The laminate according to any one of claims 1 to 5, wherein the insulating layer is an insulating layer further containing at least one inorganic filler selected from the group consisting of aluminum oxide, silicon oxide, boron nitride, and aluminum nitride.
The method for producing a laminated sheet according to any one of claims 1 to 6, comprising a step of obtaining the metal sheet by roughening at least one surface of a raw metal sheet obtained by a rolling method. A manufacturing method of a laminated board.