JP2007001230A - Method for manufacturing laminate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a laminate by which a thin laminate of 0.07 mm or thinner can be inexpensively and effectively manufactured hardly generating voids and thin spots. <P>SOLUTION: The laminate thinner of 0.07 mm or thinner is manufactured by arranging at least one sheet of cushion sheets on the outside faces of the laminate comprising one or more sheets of prepregs formed by impregnating a base material of the mass per unit area of 50 g/cm<SP>2</SP>or less with a thermosetting resin composition and incompletely curing the same and metal sheets or mold-release sheets arranged on one or both faces of the same, sandwitching the same with metal plates, and heating, compressing, and shaping the same. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a laminated board used for manufacturing a printed wiring board.

  In recent years, with the increasing need for thinner printed wiring boards accompanying the reduction in thickness and size of electronic devices, the demand for thinner metal foil-clad laminates used in the production of printed wiring boards has increased. In order to reduce the thickness of the metal foil-clad laminate, for example, the copper foil is 0.1 mm or less, the insulating layer is 35 μm or less, the resin content of the prepreg is 60 to 80%, and the thickness of the prepreg is 0.00. It has been proposed to use one having a length of 1 mm or less (for example, see Patent Document 1).

The laminated plate is made of, for example, a sheet-like prepreg produced by impregnating a base material such as a glass woven fabric (glass cloth) with a thermosetting resin composition such as an epoxy resin, and drying and semi-curing, and a metal foil or a mold release It is manufactured by stacking sheets and heating and pressing them. Specifically, metal plates such as multiple stainless steel plates are placed between cushion materials such as multiple kraft papers and rubber cushion boards, and metal foil or release sheets are placed between the metal plates. In the meantime, the prepreg is put and heated and pressurized to produce. And in order to manufacture a laminated board cheaply and efficiently, shape | molding by the size of 1 m x 1 m or more is performed. When a laminated plate of the above size is manufactured, the metal plate to be used also increases in size, thereby limiting the thickness accuracy of the metal plate and causing a thickness deviation. Normally, when a thin laminated plate having a thickness of 0.07 mm or less is manufactured, voids and scum tend to occur when the pressure distribution received by the laminated plate during molding is not uniform. According to the above manufacturing method, the unevenness of the press hot platen or the metal plate for conveyance can absorb the unevenness difference by the cushion material and make the pressure distribution uniform, but the thickness deviation of the metal plate On the other hand, it was difficult to absorb with the cushion material, and it was necessary to absorb with the resin flow property of the prepreg itself. However, when the thickness of the manufactured laminate is 0.07 mm or less, the total resin amount is so small that the thickness deviation of the metal plate cannot be absorbed by the resin flow property of the prepreg itself, and as a result There has been a problem that the pressure distribution becomes non-uniform and voids and blurring are likely to occur.
Japanese Patent Laid-Open No. 08-118541

  The present invention provides a method for producing a laminated plate that is less likely to cause voids and scum and can be produced inexpensively and efficiently in a thin laminated plate having a thickness of 0.07 mm or less from the background described above. The challenge is to do.

In order to solve the above-mentioned problems, the present invention firstly includes one or a plurality of sheets obtained by impregnating a base material having a basis weight of 50 g / cm ² or less with a thermosetting resin composition and semi-curing it. At least one cushion sheet is disposed on the outer surface of a laminate composed of a prepreg and a metal foil or release sheet disposed on one or both sides of the prepreg, and these are sandwiched between metal plates and heated and pressed. Thus, a laminate having a thickness of 0.07 mm or less is manufactured.

  And secondly, in the manufacturing method of the above-mentioned laminated board, two metal foils are arranged between the prepregs by aligning the surfaces with low surface roughness of the metal foils.

  Thirdly, in the first method for producing a laminated board, a composite foil of copper foil-aluminum foil-copper foil (CAC foil) is disposed between the prepregs, thereby providing a plurality of prepregs. A metal foil or a release sheet is arranged on one side or both sides of the sheet.

  The invention of the present application is fourthly, in the manufacturing method of the above laminate, the size of the metal foil or the release sheet is made smaller than that of the prepreg, and this is placed in the center of the prepreg and subjected to heat and pressure molding. The prepregs are bonded together to integrate the laminated plates.

  According to a fifth aspect of the present invention, in the method for manufacturing a laminated board, the cushion sheet includes three layers including a molten layer as an intermediate layer and release layers on both sides thereof. In the fifth method for producing a laminated board, the melting temperature of the molten layer of the cushion sheet is in a temperature range of 70 to 110 ° C., and the melting temperature of the prepreg is in a temperature range of 110 to 150 ° C. And

  And 7th, in the manufacturing method of said laminated board, the inorganic filler is contained in the prepreg.

  Further, eighthly, in the above method for producing a laminate, the minimum value of the melt viscosity of the thermosetting resin composition of the prepreg at the time of heat and pressure molding is in the range of 10,000 to 100,000 poise.

  A ninth aspect of the present invention is characterized in that, in the ninth method for manufacturing a laminated board, the base material is a glass cloth, and in a tenth aspect, in the ninth method for manufacturing a laminated board, the glass cloth is flat. -It is characterized by being opened.

  The eleventh aspect is characterized in that, in the method for manufacturing a laminate, the height of the resin protrusion formed on the surface of the prepreg is 10 μm or less.

  And twelfth, in the eleventh laminate manufacturing method, the thermosetting resin composition of the prepreg can be melted from a laminate in which a metal foil or a release sheet is disposed on one or both sides of the prepreg. After passing between two heating rolls heated to a temperature, the resin projections formed on the surface of the prepreg are made to have a height of 10 μm or less by cooling.

According to the first invention as described above, one or a plurality of prepregs and one side thereof obtained by impregnating a base material having a basis weight of 50 g / cm ² or less with a thermosetting resin composition and semi-curing the base material. Alternatively, at least one cushion sheet is disposed on the outer surface of a laminate composed of a metal foil or a release sheet disposed on both sides, and these are sandwiched between metal plates and heated and pressed to form a plate thickness. By manufacturing a laminated plate having a thickness of 0.07 mm or less, voids and scum are less likely to be generated, and it can be manufactured inexpensively and efficiently.

  According to said 2nd invention, two metal foil is arrange | positioned between a prepreg and the surfaces with low surface roughness of metal foil are match | combined, The number of production is increased, without increasing a metal plate. It can be increased and can be manufactured inexpensively and efficiently.

  According to said 3rd invention, it does not increase a metal plate similarly to 2nd invention by arrange | positioning the composite foil of copper foil-aluminum foil-copper foil (CAC foil) between a prepreg, and a prepreg. In addition, the number of production can be increased, and it can be manufactured at low cost and efficiently.

  According to the fourth aspect of the invention, the metal foil or the release sheet is made smaller than the prepreg and is placed in the center of the prepreg and heat-press molded, and the prepregs at the ends are bonded to each other for lamination. By integrating the plates, the integrated laminated plate is simultaneously cut into a workpiece size with a saw blade or the like, thereby improving handling properties and preventing breakage that easily occurs during handling.

  According to said 5th invention, the cushion sheet | seat is comprised by three layers which provided the molten layer as an intermediate | middle layer, and provided the release layer on the both sides, Therefore The pressure which a laminated body receives at the time of heat press molding Since this cushion sheet is filled in the lower portion by melting the molten layer, the pressure distribution received by the laminate can be made uniform, and the generation of voids and scum can be further reduced.

  According to said 6th invention, when the melting temperature of the molten layer of a cushion sheet is a temperature range of 70-110 degreeC, and the melting temperature of a prepreg is a temperature range of 110-150 degreeC, said 5th The effect of the invention can be further improved.

  According to said 7th invention, when an inorganic filler contains in a prepreg, thermal expansion can be reduced and conduction | electrical_connection reliability can be improved.

  According to said 8th invention, when the minimum value of the melt viscosity of the thermosetting resin composition of the prepreg at the time of heat-pressure molding is in the range of 10,000 to 100,000 poise, the resin flow property of the prepreg itself is suitably It is controlled and the accuracy of the thickness of the laminated plate can be improved.

  According to said 9th invention, when a base material is a glass cloth, the heat resistance of a laminated board, moisture resistance, an elasticity modulus, and rigidity can be made high.

  According to the tenth aspect of the invention, since the glass cloth has been flattened and opened, generation of voids and scum can be further reduced in addition to the effects of the ninth aspect of the invention.

  According to the eleventh aspect of the invention, since the height of the resin protrusion formed on the surface of the prepreg is 10 μm or less, it is possible to make it difficult for the resin protrusion to remain on the laminate after the heat and pressure molding.

  According to the twelfth aspect of the present invention, the laminate in which the metal foil or the release sheet is disposed on one or both sides of the prepreg is heated to a temperature at which the thermosetting resin composition of the prepreg can be melted. After passing between the heating rolls and cooling, the height of the resin protrusion can be easily reduced to 10 μm or less, and the transfer of the thermosetting resin composition to the heating roll can be prevented.

  The present invention has the above-described features, and the best mode for carrying out the invention will be described below.

  The present invention is composed of one or a plurality of prepregs obtained by impregnating a base material with a thermosetting resin composition and semi-cured, and a metal foil or a release sheet disposed on one or both sides thereof. At least one cushion sheet is disposed on the outer surface of the laminate. That is, a cushion sheet is arranged on one or both sides of the laminate, and these are sandwiched between metal plates and heated and pressed to produce a laminate having a thickness of 0.07 mm or less.

In order to make the base material in the present invention a laminated plate having a thickness of 0.07 mm or less, it is essential to use a substrate having a basis weight of 50 g / cm ² or less. If the weight per unit area exceeds 50 g / cm ² , the thickness of the manufactured laminate exceeds 0.07 mm, and the laminate cannot be thinned. The lower limit of the basis weight of the base material is 15 g / cm ² that can be produced as the base material.

  As metal foil in this invention, if it is metal foil, it will not specifically limit, For example, foil, such as copper or copper alloy, nickel or nickel alloy, aluminum, or aluminum alloy, can be used. And as thickness of this metal foil, it is 9-35 micrometers generally.

  As the release sheet in the present invention, a fluorine-based sheet or a metal foil whose surface is coated with a resin containing silicon can be used.

  In the present invention, when a plurality of prepregs are used, two metal foils may be arranged between the prepregs so that the surfaces with low surface roughness of the metal foils face each other. Moreover, in this invention, when using several prepreg, you may make it arrange | position the composite foil of copper foil-aluminum foil-copper foil (CAC foil) between a prepreg and a prepreg.

  The metal foil or release sheet in the present invention may be formed by heating and pressing by making the size smaller than that of the prepreg and placing it in the center of the prepreg. As a result, the prepregs at the end are bonded to each other, and a plurality of laminated plates are integrated. The integrated laminate is cut at the end, that is, the portion where the prepregs are bonded with a saw blade or the like, and is cut with a desired workpiece size, so that handling properties can be achieved when producing the laminate. Thus, it is possible to prevent breakage that easily occurs during handling.

  Examples of the cushion sheet in the present invention include kraft paper, fluorine release sheet, felt material, aromatic polyamide paper, etc., and it is composed of three layers including a melt layer as an intermediate layer and release layers on both sides thereof. It may be a cushion sheet.

  In the cushion sheet having the above three-layer structure, the cushion sheet is filled by melting of the molten layer in a portion where the pressure applied to the laminate during heat and pressure molding is reduced, so that the pressure distribution received by the laminate can be made uniform. This can further reduce the occurrence of voids and blurring. This molten layer is preferably melted before the prepreg is melted at the time of heat and pressure molding. For example, when the melting temperature of the prepreg is in the temperature range of 110 to 150 ° C, the melting temperature of the molten layer is 70 to 110 ° C. A temperature range is preferred. Examples of the material of the molten layer include epoxy resin and polyolefin, and examples of the release layer include a fluorine film and a metal sheet that do not adhere to the metal foil of the product.

  Examples of the thermosetting resin composition impregnated in the prepreg of the present invention include epoxy resins, polyimide resins, fluororesins, polyphenylene oxide resins, unsaturated polyester resins, phenol resins alone, and modifications based on these resins. A resin, a combination resin of these resins, or the like can be used. If necessary, a curing agent, a curing accelerator, various additives, an inorganic filler, and the like can be used. Examples of the inorganic filler include alumina, silica, calcium carbonate, talc, clay, barium sulfate, and aluminum hydroxide. These materials are mixed with a mixer or a blender using a solvent such as methyl ethyl ketone (MEK), methoxypropanol (MP), or dimethylformamide (DMF) to prepare a resin varnish.

The prepreg in the present invention is obtained by impregnating a base material with a resin varnish composed of the above thermosetting resin composition and semi-cured, but when this semi-cured thermosetting resin composition is heated, Once the viscosity drops, the resin flows, and when heated further, the resin hardens and stops flowing. here,
It is preferable that the minimum value of the melt viscosity of the thermosetting resin composition of the prepreg at the time of heating and pressing is in the range of 10,000 to 100,000 poise. Thereby, the resin flow property of the prepreg itself is suitably controlled at the time of heat and pressure molding, and the accuracy of the thickness of the laminated plate can be improved. If it is less than 10,000 poise, the resin tends to flow and the plate thickness variation increases, which is not preferable. If it exceeds 100,000 poise, voids are likely to occur, which is not preferable.

As described above, the base material in the invention of the present invention uses a fabric weight of 50 g / cm ² or less, and the types thereof are inorganic fibers such as glass fibers, aramid fibers, polyester fibers, polyimide fibers, polyacrylic fibers and the like. A woven or non-woven fabric of fibers can be used. Among them, a glass cloth which is a woven fabric of glass fibers is preferable because it is easily available and can increase the heat resistance, moisture resistance, elastic modulus and rigidity of the laminate. Further, when using a glass cloth, it may be difficult to apply pressure to a gap portion between the yarns of the glass cloth and voids may be generated. Therefore, it is preferable to flatten the gap between the yarns. And it is preferable to carry out the fiber opening process since the resin does not easily penetrate between the filaments.

  In the present invention, the height of the resin protrusion formed on the surface of the prepreg is set to 10 μm or less. When the base material is rubbed in a process such as spinning or weaving, the resin protrusions are in a state where the filament constituting the base material generally called “fluff” protrudes from the surface, and the base material is impregnated with the thermosetting resin composition. Then, when the prepreg is produced, the thermosetting resin composition aggregates on the protruding filament portion, and is formed as a protrusion of the thermosetting resin composition on the surface of the obtained prepreg. When a prepreg having such protrusions is heated and pressed to produce a laminate, particularly when the height of the prepreg exceeds 10 μm, it may remain without being smoothed. For this reason, it is preferable to remove the resin protrusions on the surface of the prepreg in advance or to make the height 10 μm or less.

  And as a method of making the height of such a resin protrusion 10 μm or less, a method of mechanically crushing and smoothing through a prepreg between two rolls is preferable, but preferably the temperature of the roll is adjusted to that of the prepreg. By setting the temperature at which the thermosetting resin composition melts, for example, at a temperature of 80 to 130 ° C., the resin at the protruding portion can be melted and smoothed. It is also effective to provide a cooling step in order to prevent the resin from curing. As a cooling process, you may make it let a prepreg pass between two rolls of the temperature of about 10 degreeC like the Example mentioned later, for example. Here, in order to prevent the resin of the prepreg from being transferred to the roll, it is preferable that a laminate in which a metal foil or a release sheet is disposed on one side or both sides of the prepreg is passed through the roll.

  Hereinafter, examples will be shown and described in more detail. Of course, the present invention is not limited by the following examples.

<Adjustment of resin varnish>
80 parts of brominated bisphenol A type epoxy resin (YDB-500KEK80 manufactured by Toto Kasei Co., Ltd.) (where “part” represents “part by weight”, the same shall apply hereinafter) cresol novolac epoxy resin (YDCN-220EK75 10 parts, 1.8 parts of dicyandiamide, 0.04 part of 2-ethyl 4-methylimidazole, 40 parts of aluminum hydroxide (CL303, manufactured by Sumitomo Chemical Co., Ltd.) are dissolved in 30 parts of methyl ethyl ketone to obtain an epoxy resin varnish. Obtained.
<Manufacture of prepreg A>
The epoxy resin varnish was impregnated in glass cloth A (thickness: 0.06 mm, weight per unit weight: 48 g / m ² WEA 1078, manufactured by Nitto Boseki Co., Ltd.) so that the amount of resin was 56%, and heated to obtain prepreg A. The minimum melt viscosity of this prepreg A at 2.5 ° C./min was 43,000 poise. The melt viscosity at this time was measured by using a parallel plate with MR-300 manufactured by Rheology.
<Manufacture of prepreg B>
The epoxy resin varnish was impregnated into glass cloth A so that the amount of resin was 56% and heated to obtain prepreg B having a hardness different from that of prepreg A. The minimum value of the melt viscosity of this prepreg B at 1.5 ° C./min was 3200 poise.
<Manufacture of prepreg C>
The epoxy resin varnish is impregnated into a glass cloth C having a fluff (thickness: 0.06 mm, weight per unit weight: 48 g / m ² WEA 1078, manufactured by Nitto Boseki Co., Ltd.) so that the amount of resin becomes 56%, and heated to prepare prepreg C. Obtained. This prepreg C had a minimum melt viscosity of 15000 poise at 1.5 ° C./min. The height of the surface protrusion on the fluff was 50 μm.
<Manufacture of prepreg D>
After placing an aluminum release sheet A (20M2S Sun Aluminum Industry Co., Ltd.) on both sides of the prepreg C, it was passed between two rolls with a wire thickness of 25 kg / cm ² heated to 110 ° C. which was rotating. Then, it passed between the two rolls of 10 degreeC which are rotating, and the aluminum release sheet was peeled after that and the prepreg D was obtained. The minimum value of the melt viscosity at 2.5 ° C./min of this prepreg D was 16000 poise. Moreover, the height of the surface protrusion of the fluff was 3 μm.
<Manufacture of prepreg E>
The epoxy resin varnish was impregnated into glass cloth D (thickness 0.06 mm, weight per unit weight 48 g / m ² WEA 1080, manufactured by Nitto Boseki Co., Ltd.) so that the amount of resin was 56%, and heated to obtain prepreg E. This prepreg E had a minimum melt viscosity of 36000 poise at 2.5 ° C./min.
<Manufacture of prepreg F>
The epoxy resin varnish was impregnated into glass cloth D (thickness 0.06 mm, weight per unit weight 48 g / m ² WEA 1080, manufactured by Nitto Boseki Co., Ltd.) so that the amount of the resin was 56%, and heated to adjust the prepreg E and the hardness. Different prepregs F were obtained. The minimum value of the melt viscosity of this prepreg F at 1.5 ° C./min was 4500 poise.
<Manufacture of prepreg G>
The epoxy resin varnish is impregnated into a glass cloth E with a fluff (thickness: 0.06 mm, weight per unit weight: 48 g / m ² WEA 1080, manufactured by Nitto Boseki Co., Ltd.) so that the amount of resin becomes 56%, and heated to prepare prepreg G Obtained. The minimum value of the melt viscosity of this prepreg G at 1.5 ° C./min was 2200 poise. Moreover, the height of the surface protrusion of the fluff was 60 μm.
<Example 1>
A TPX film (CR1031, made by Mitsui Chemicals, Inc.) consisting of three layers whose intermediate layer melts at 70 ° C. is placed on the SUS plate as a cushion sheet, and copper foil 18 μm, prepreg A, copper foil, and TPX After arranging in the order of the film, the SUS plate is arranged at the top, and this component is set on the hot platen of the press machine, the product heating rate is 2.5 ° C./min, the product temperature is 170 ° C. or more and 60 minutes, Heat-press molding was performed at a pressure of 3 MPa to obtain a copper-clad laminate.
<Example 2>
A TPX film is placed on the top of the SUS plate. On top of that, copper foil 18μm, prepreg A, one copper foil (MAT side downward), one copper foil (MAT side upward), prepreg A, copper foil (MAT side downward) ) After placing one sheet, one copper foil (MAT side upward), prepreg A, copper foil 18 μm, and TPX film in this order, a SUS plate was placed on the top.

At this time, the SUS plate and the prepreg A were made the same size, and the copper foil between the prepregs A was 2 cm shorter than the prepreg A in both vertical and horizontal sizes, and placed in the center of the prepreg A. This component was set on a hot platen of a press machine, and was heated and pressed in the same manner as in Example 1. After the molding, the laminated board in which the three sheets were integrated was disassembled by cutting with a saw blade to obtain three copper-clad laminated boards.
<Example 3>
A TPX film is placed on the upper part of the SUS plate, and one aluminum release sheet (20B2C-M manufactured by Sun Aluminum Co., Ltd.), prepreg A, one aluminum release sheet, prepreg A, aluminum release sheet 1 After the sheet, the prepreg A, one aluminum release sheet, and the TPX film were disposed in this order, the SUS plate was disposed on the top. This component was set on a hot platen of a press machine, and was heated and pressed in the same manner as in Example 1. After the molding, the laminated board in which the three sheets were integrated was cut with a saw blade, and then the aluminum release sheet was peeled off to obtain three copper-clad laminated boards.
<Example 4>
A TPX film is placed on top of the SUS plate, and copper foil 18 μm, prepreg A, CAC foil (copper foil-aluminum foil-copper foil, manufactured by Nikko Materials Co., Ltd.), prepreg A, CAC foil, prepreg A After arranging the copper foil 18 μm and the TPX film in this order, the SUS plate was arranged on the top. This component was set on a hot platen of a press machine, and was heated and pressed in the same manner as in Example 1. After the molding, the laminated board in which the three sheets were integrated was cut with a saw blade, and then the aluminum layer and the copper foil layer of the CAC foil were peeled off to obtain three copper-clad laminated boards.
<Example 5>
Example 1 is the same as Example 1 except that prepreg B is used in place of prepreg A, product heating rate is 1.5 ° C./min, product temperature is 170 ° C. or more and 60 minutes, and pressure is 3 MPa. Thus, a copper-clad laminate was obtained.
<Example 6>
In Example 5, a copper-clad laminate was obtained in the same manner as in Example 5 except that three sheets of fluorine film 80 μm (Tedlar film manufactured by DuPont, USA) were used instead of the TPX sheet.
<Example 7>
After placing 18 μm of copper foil on both sides of the prepreg C, after passing between two rolls of wire thickness 25 kg / cm ² heated to 110 ° C. rotating, two rolls of 10 ° C. rotating Throughout the process, a composition A was obtained.

A TPX film was placed on top of the SUS plate, composition A was placed on top of it, and further a TPX film was placed, and then a SUS plate was placed on the top. This component was set on a hot platen of a press machine and heat-press molded in the same manner as in Example 1 to obtain a copper-clad laminate.
<Example 8>
A copper clad laminate was obtained in the same manner as in Example 1 except that prepreg C was used instead of prepreg A in Example 1.
<Example 9>
A copper clad laminate was obtained in the same manner as in Example 1 except that prepreg D was used instead of prepreg A in Example 1.
<Comparative Example 1>
Place the TPX film on the top of the SUS plate, and place the copper foil 18μm, prepreg E, copper foil 18μm on the top, then place the SUS plate on the top, and place this component on the hot platen of the press machine It set and heat-pressed similarly to Example 1, and obtained the copper clad laminated board.
<Comparative example 2>
Similar to Example 1, except that prepreg F was used instead of prepreg E in Comparative Example 1, and the product temperature rising rate was 1.5 ° C./min, the product temperature was 170 ° C. or more and 60 minutes, and the pressure was 3 MPa. Thus, a copper-clad laminate was obtained.
<Comparative Example 3>
Copper foil 18μm on top of SUS plate, prepreg F, 1 copper foil (MAT side downward), 1 copper foil (MAT side upward), prepreg F, 1 copper foil (MAT side downward), copper foil (MAT side) (Upward) One sheet, prepreg F, and copper foil 18 μm were disposed in this order, and then a SUS plate was disposed on the top. This component was set on a hot platen of a press machine and heat-press molded in the same manner as in Example 1 to obtain a copper-clad laminate.
<Comparative example 4>
A copper clad laminate was obtained in the same manner as in Comparative Example 2 except that prepreg G was used instead of prepreg F in Comparative Example 2.
<Comparative Example 5>
A copper clad laminate was obtained in the same manner as in Comparative Example 2 except that prepreg B was used in place of prepreg F in Comparative Example 2.

About the laminated board obtained above, (1) the number of generated voids, (2) board thickness, (3) surface roughness, and (4) protrusion height were measured. However, (4) About protrusion height, only the laminated board of Examples 8-10 and the comparative example 4 was measured.
Each measuring method is as follows.
(1) Number of generated voids: For copper-clad laminates, the copper foil was removed by etching, and the number of generated voids with N = 10 was examined.
(2) Plate thickness: The copper foil was removed by etching, the number of N = 5, 4 points at the center and 4 points at the end were measured with a micrometer, and the average, Max, Min, and σn−1 were calculated.
(3) Surface roughness: Measured with a Surfcom 550A roughness meter manufactured by Tokyo Seimitsu Co., Ltd.
(4) Projection height: Measured with a Surfcom 550A roughness meter manufactured by Tokyo Seimitsu Co., Ltd.

  The results are shown in Table 1.

表１の結果より、積層物の外側面に少なくとも１枚以上のクッションシートを配置し、これらを金属プレートで挟み加熱加圧成形する（実施例１〜９）ことで、クッションシートを配置しないで加熱加圧成形した比較例１〜５に比べてボイドの発生を抑えることができた。また、プリプレグの熱硬化性樹脂組成物の溶融粘度最低値が１００００〜１０００００ポイズの範囲であることにより、積層板の板厚の精度を向上させることができることが確認された。さらに、プリプレグの片面または両面側に金属箔あるいは離型シートを配置した積層物を、プリプレグの熱硬化性樹脂組成物が溶融可能な温度まで加熱された２本の加熱ロール間に通した後、冷却することでプリプレグの表面に形成される樹脂突起の高さを１０μｍ以下にすることにより、得られる積層板の突起高さも１０μｍ以下にすることができることも確認された。

From the results of Table 1, at least one cushion sheet is disposed on the outer surface of the laminate, and these are sandwiched between metal plates and subjected to heat and pressure molding (Examples 1 to 9), so that the cushion sheet is not disposed. The generation of voids could be suppressed as compared with Comparative Examples 1 to 5 which were heat and pressure molded. Moreover, it was confirmed that the precision of the thickness of a laminated board can be improved by the melt viscosity minimum value of the thermosetting resin composition of a prepreg being the range of 10,000-100,000 poise. Furthermore, after passing the laminate in which the metal foil or the release sheet is disposed on one side or both sides of the prepreg, between two heating rolls heated to a temperature at which the thermosetting resin composition of the prepreg can be melted, It was also confirmed that by cooling, the height of the resin protrusion formed on the surface of the prepreg can be 10 μm or less, and the height of the protrusion of the obtained laminate can be 10 μm or less.

Claims (12)

One or a plurality of prepregs obtained by impregnating a thermosetting resin composition into a base material having a basis weight of 50 g / cm ² or less and semi-cured, and a metal foil or a release sheet disposed on one or both sides thereof At least one cushion sheet is disposed on the outer surface of the laminate composed of the above, and these are sandwiched between metal plates and heated and pressed to produce a laminate having a thickness of 0.07 mm or less. A method for producing a laminated board.   In the manufacturing method of the laminated board of Claim 1 by which metal foil is arrange | positioned at the single side | surface or both surface sides of several prepregs, the surfaces with low surface roughness of metal foil are match | combined, and it is between prepregs and prepregs. A method for producing a laminated board, comprising arranging two metal foils.   By arranging a composite foil of copper foil-aluminum foil-copper foil (CAC foil) between the prepregs, a metal foil or a release sheet is arranged on one or both sides of a plurality of prepregs. The manufacturing method of the laminated board of Claim 1 characterized by the above-mentioned.   The size of the metal foil or release sheet is made smaller than that of the prepreg, and this is placed in the center of the prepreg and heat-press molded, and the laminates are integrated by bonding the prepregs at the ends. The manufacturing method of the laminated board in any one of Claim 1 to 3.   The method for manufacturing a laminated board according to any one of claims 1 to 4, wherein the cushion sheet is composed of three layers including a molten layer as an intermediate layer and release layers on both sides thereof.   The method for producing a laminated board according to claim 5, wherein the melting temperature of the molten layer of the cushion sheet is in a temperature range of 70 to 110 ° C, and the melting temperature of the prepreg is in a temperature range of 110 to 150 ° C.   The method for producing a laminate according to any one of claims 1 to 6, wherein the prepreg contains an inorganic filler.   The method for producing a laminated board according to any one of claims 1 to 7, wherein the minimum value of melt viscosity of the thermosetting resin composition of the prepreg at the time of heat and pressure molding is in the range of 10,000 to 100,000 poise.   The method for producing a laminated board according to any one of claims 1 to 8, wherein the substrate is a glass cloth.   The method for producing a laminated board according to claim 9, wherein the glass cloth is flattened and opened.   The method for producing a laminated board according to any one of claims 1 to 10, wherein the height of the resin protrusion formed on the surface of the prepreg is 10 µm or less.   The laminate having a metal foil or release sheet disposed on one or both sides of the prepreg is cooled after passing between two heating rolls heated to a temperature at which the thermosetting resin composition of the prepreg can be melted. The height of the resin protrusion formed in the surface of a prepreg by this is made into 10 micrometers or less, The manufacturing method of the laminated board of Claim 11 characterized by the above-mentioned.