JP2014024269A - Method for producing cured product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a cured product, capable of producing a cured product whose dimensional variations are less likely to occur.SOLUTION: The method for producing a cured product includes the steps of: preparing a laminate (laminated sheet 40A) comprising a prepreg, in which a fiber base material 2 is impregnated with a thermosetting resin material, and a sheet (metal layer 12) temporarily bonded to at least one of the front surface and the rear surface of the prepreg; and heating the laminate without pressurizing it to promote curing of the thermosetting resin material, thereby finally bonding the sheet and the prepreg together.

Description

  The present invention relates to a method for producing a cured body.

Conventionally, a laminated board in which a metal foil such as a copper foil is provided on the surface of a prepreg is used for a printed wiring board or the like.
Such a laminated board is manufactured as follows (for example, refer patent document 1).
A metal foil is temporarily bonded to a coated cloth obtained by impregnating a sheet-shaped material with a resin composition. Specifically, a coating cloth and a metal foil are supplied and temporarily bonded between a pair of rolls.
Thereafter, the temporarily bonded coating cloth and the metal foil are disposed between a pair of hot plates, and are bonded together by being sandwiched between the hot plates.

JP 2007-136835 A

Such a laminated board is incorporated in a printed wiring board. And a semiconductor element etc. are mounted in a printed wiring board, and a printed wiring board will be heated by processes, such as reflow. As a result of studies by the present inventors, it has been found that when a printed wiring board is manufactured using the laminate manufactured by the above-described manufacturing method, the dimensional variation increases before and after the heating process such as reflow. This is presumably due to the following reasons.
At the time of manufacturing the laminated plate, the coated cloth and the metal foil are pressed and bonded together with a pair of hot plates. When the coated cloth and the metal foil are sandwiched and heated, the coated cloth is cured while being pulled. Accordingly, there is a residual stress in the tensile direction inside the laminate. When heating such as reflow is performed, the laminate is heated, the resin composition inside the coated fabric becomes soft, and the tensile stress inside the coated fabric is relaxed. When the tensile stress is relaxed, the resin composition tends to shrink. For this reason, the laminated plate contracts after reflowing, and dimensional variation occurs in the laminated plate. When the dimensional variation occurs in the laminated board, the dimensional variation also occurs in the printed wiring board itself.

The present invention has been invented based on the above findings.
According to the present invention, a laminate comprising a prepreg impregnated with a thermosetting resin material and a sheet temporarily bonded to at least one of the front and back surfaces of the prepreg with respect to a fiber base material. Production of a cured body including a step of preparing, and a step of heating and heating the thermosetting resin material without pressurizing the laminate, and finally adhering the sheet and the prepreg. A method is provided.

Here, as a sheet | seat, either metal foil, a resin sheet, etc. can be used.
Moreover, heating a laminated body without pressurizing means heating a laminated body in the state which the pressure over atmospheric pressure does not apply to a laminated body from the outside.

According to this invention, when the sheet and the prepreg are permanently bonded, the laminated body of the sheet and the prepreg is heated without being pressurized, and the thermosetting resin layer is cured.
Thereby, since a prepreg is not pressurized at the time of this adhesion | attachment, it becomes difficult to generate | occur | produce a stress inside a prepreg, and the residual stress which generate | occur | produces inside a hardening body can be reduced.
Even when such a cured body is heated, dimensional fluctuations hardly occur before and after heating, and the cured body has high reliability.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the hardening body which can manufacture the hardening body which a dimension fluctuation does not produce easily can be provided.

It is sectional drawing of the lamination sheet concerning one Embodiment of this invention. It is a schematic diagram which shows a part of laminated sheet manufacturing apparatus. It is sectional drawing along the lamination sheet conveyance direction of a part of lamination sheet manufacturing apparatus. It is the sectional view on the AA line in FIG. FIG. 5 is a sectional view taken along line BB in FIG. 3. FIG. 4 is an enlarged view of a region [C] surrounded by an alternate long and short dash line in FIG. 3. It is a figure which shows a 2nd heating means. It is a schematic diagram which shows a part of laminated sheet manufacturing apparatus. It is a schematic diagram which shows a part of laminated sheet manufacturing apparatus. It is sectional drawing of the DD direction of FIG. It is a figure which shows the result of an Example and a comparative example, and is a figure which shows the dimensional change rate of the TD direction of a hardening body. It is a figure which shows the result of an Example and a comparative example, and is a figure which shows the dimensional change rate of MD direction of a hardening body.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same components are denoted by the same reference numerals, and detailed description thereof is appropriately omitted so as not to overlap.
<Laminated sheet>
First, the laminated sheet 40B will be described with reference to FIG.

A laminated sheet 40B shown in FIG. 1 is positioned on one side (upper surface) side of a thin plate-like (flat plate) fiber base (base) 2 and the fiber base 2 and is a solid or semi-solid first. The first resin layer (resin layer) 3 composed of the resin composition and the second surface composed of the solid or semi-solid second resin composition located on the other surface (lower surface) side of the fiber substrate 2. 2 resin layers (resin layers) 4 and metal layers 12 formed on the first resin layer 3 and the second resin layer 4 respectively.
In the laminated sheet 40B, the resin layers 3 and 4 are completely cured and are in a C stage state.
The laminated sheet 40B is used for a multilayer printed wiring board (circuit board), and is used as a core material. A circuit layer is formed by selectively removing the metal layer of the laminated sheet 40B, and a multilayer printed wiring board (circuit board) is formed by alternately laminating prepregs and circuit layers on the front and back surfaces of the laminated sheet 40B. ) Is obtained.

The fiber base material 2 has a function of improving the mechanical strength of the laminated sheet 40B.
Examples of the fiber substrate 2 include glass fiber substrates such as glass woven fabric and glass nonwoven fabric, polyamide resin fibers such as polyamide resin fibers, aramid fibers such as aromatic polyamide resin fibers and wholly aromatic polyamide resin fibers, Consists of polyester resin fibers such as polyester resin fibers, aromatic polyester resin fibers, wholly aromatic polyester resin fibers, woven or non-woven fabrics mainly composed of polyparaphenylene benzobisoxazole, polyimide resin fibers, fluororesin fibers, etc. Synthetic fiber base materials, kraft paper, cotton linter paper, fiber base materials such as organic fiber base materials such as paper fiber base materials mainly composed of linter and kraft pulp mixed paper, and the like.
In addition, the fiber base material may use any 1 type of the fiber mentioned above, and may use 2 or more types.

  Among these, it is preferable that the fiber base material 2 is a glass fiber base material. By using such a glass fiber base material, the mechanical strength of the laminated sheet 40B can be further improved. Moreover, there is an effect that the thermal expansion coefficient of the laminated sheet 40B can be reduced.

  Examples of the glass constituting such a glass fiber substrate include any of E glass, C glass, A glass, S glass, D glass, NE glass, T glass, H glass, Q glass, and quartz glass. Can be mentioned. Among these, it is preferable that glass is S glass, T glass, quartz glass, or Q glass. Thereby, the thermal expansion coefficient of a glass fiber base material can be made comparatively small, For this reason, the laminated sheet 40B can be made as small as possible in the thermal expansion coefficient.

  Although the average thickness T of the fiber base material 2 is not specifically limited, It is preferable that it is 150 micrometers or less, It is more preferable that it is 100 micrometers or less, It is further more preferable that it is about 10-50 micrometers. By using the fiber base 2 having such a thickness, it is possible to reduce the thickness while securing the mechanical strength of the laminated sheet 40B. Furthermore, the workability and dimensional stability of the laminated sheet 40B can be improved.

  The first resin layer 3 is provided on one surface side of the fiber substrate 2, and the second resin layer 4 is provided on the other surface side. The first resin layer 3 is composed of a first resin composition, while the second resin layer 4 is composed of a second resin composition. The first resin composition and the second resin composition may be the same composition or different. In this embodiment, the same composition is used.

  In the present embodiment, the metal layer 12 is formed on each of the first resin layer 3 and the second resin layer 4. The metal layer 12 becomes a wiring portion (conductor pattern) by performing etching or laser processing, for example. For this reason, the 1st resin composition and the 2nd resin composition are set as the composition which is excellent in adhesiveness with a metal.

As shown in FIG. 1, in this embodiment, a part of the fiber base 2 in the thickness direction is impregnated with the first resin composition (first resin layer 3) (hereinafter, this part is referred to as “first impregnation”. Part 31 ”), the remaining part of the fiber base material 2 not impregnated with the first resin composition is impregnated with the second resin composition (second resin layer 4) (hereinafter this part is referred to as“ part 31 ”). This is referred to as “second impregnation portion 41”). Accordingly, the first impregnation portion 31 that is a part of the first resin layer 3 and the second impregnation portion 41 that is a part of the second resin layer 4 are located in the fiber base 2. And in the fiber base material 2, the 1st impregnation part 31 (lower surface of the 1st resin layer 3) and the 2nd impregnation part 41 (upper surface of the 2nd resin layer 4) are contacting. In other words, the first resin composition is impregnated into the fiber substrate 2 from the upper surface side of the fiber substrate 2, and the second resin composition is impregnated from the lower surface side of the fiber substrate 2. The voids in the fiber base material 2 are filled with these resin compositions.
In addition, the area | region which the fiber base material 2 is not impregnated among the 1st resin layers 3 is the non-impregnation part 32, and the area | region which the fiber base material 2 is not impregnated among the 2nd resin layers 4 is non-impregnated. It is an impregnation part 42.
In the present embodiment, the thickness of the first impregnation part 31 and the thickness of the second impregnation part 41 are equal.
Furthermore, the thickness of the first resin layer 3 excluding the first impregnation part 31 (first non-impregnation part 32) and the part of the second resin layer 4 excluding the second impregnation part 41 (second non-impregnation part). The thickness of the impregnation part 42) is equal. The thickness of the 1st non-impregnation part 32 and the thickness of the 2nd non-impregnation part 42 are 2-20 micrometers, for example. The thickness of the first impregnation part 31 and the thickness of the second impregnation part 41 may be different, and the thickness of the first non-impregnation part 32 and the thickness of the second non-impregnation part 42 May be different.
Reference numeral 20 schematically shows a boundary line between the first impregnation portion 31 and the second impregnation portion 41.

As shown in FIG. 2, the first resin layer 3 is supplied to the manufacturing apparatus 30 </ b> A of the laminated sheet manufacturing apparatus 30 as a long thin plate-like first sheet 5 a in a state where the metal layer 12 is stacked. The second resin layer 4 is also supplied to the laminated sheet manufacturing apparatus 30 as a long thin plate-like second sheet 5b in a state where the metal layer 12 is laminated.
A support base 51 for supporting the first resin layer 3 is provided on the surface of the first sheet 5a opposite to the metal layer 12 of the first resin layer 3 (see FIG. 3). Similarly, a support base 51 for supporting the second resin layer 4 is provided on the surface of the second sheet 5b opposite to the metal layer 12 of the second resin layer 4 (see FIG. 3). In FIG. 2, the support base 51 is not shown for ease of viewing.
As the support base 51, for example, a resin film is preferable. Examples of the resin material constituting the resin film include any of a fluorine resin, a polyimide resin, a polyester resin such as polybutylene terephthalate, and polyethylene terephthalate. And as a resin material which comprises a resin film, since it is excellent in heat resistance and cheap, among these, a polyethylene terephthalate is preferable. Moreover, it is preferable that the process which can peel is performed to the surface at the side of the resin layer of the resin film. Thereby, as will be described later, the support base 51 and the resin layer can be easily separated.

The thickness of the support base 51 is not particularly limited, but is preferably about 8 to 70 μm, and more preferably about 12 to 40 μm.
In addition, the thickness of each resin layer 3 and 4 in sheet | seat 5a, 5b is 3-60 micrometers, for example, Preferably it is 5-30 micrometers.

As described above, the metal layer 12 is a portion that is processed into a wiring portion, and a metal foil made of a conductive metal material, such as a copper foil or an aluminum foil, is joined to a corresponding resin layer. In other words, the surface of the corresponding resin layer is plated with copper or aluminum. Moreover, in this embodiment, since the 1st resin layer 3 and the 2nd resin layer 4 have the characteristics as mentioned above, while being able to hold | maintain the metal layer 12 with high adhesiveness, it is a metal layer with high processing accuracy. 12 can be formed in the wiring portion.
The thickness of the metal layer 12 is, for example, 1 to 70 μm.

  Now, it is preferable that the first resin composition and the second resin composition have the following composition.

  Each resin composition includes, for example, a thermosetting resin, and includes at least one of a curing aid (for example, a curing agent and a curing accelerator) and an inorganic filler as necessary.

  Examples of thermosetting resins include urea (urea) resins, melamine resins, maleimide compounds, polyurethane resins, unsaturated polyester resins, resins having a benzoxazine ring, bisallyl nadiimide compounds, vinyl benzyl resins, vinyl benzyl ether resins. Any one or more of benzocyclobutene resin, cyanate resin, epoxy resin and the like can be used. Among these, the thermosetting resin is preferably a combination having a glass transition temperature of 200 ° C. or higher. For example, spiro ring-containing, heterocyclic, trimethylol type, biphenyl type, naphthalene type, anthracene type, novolak type bi- or trifunctional epoxy resin, cyanate resin (including cyanate resin prepolymer), maleimide compound, It is preferable to use either a benzocyclobutene resin or a resin having a benzoxazine ring.

  Further, by using a thermosetting resin, the crosslink density increases in the cured first resin layer 3 after a substrate to be described later is manufactured. Therefore, the heat resistance of the cured first resin layer 3 is improved. Can be achieved.

  By using the thermosetting resin and the filler in combination, the thermal expansion coefficient of the laminated sheet 40B can be reduced (hereinafter also referred to as “low thermal expansion”). Furthermore, the electrical characteristics (low dielectric constant, low dielectric loss tangent) and the like of the laminated sheet 40B can be improved.

  Examples of the epoxy resin include phenol novolac type epoxy resin, bisphenol type epoxy resin, naphthalene type epoxy resin, anthracene type epoxy resin, arylalkylene type epoxy resin and the like. One or more of these can be used as the epoxy resin.

  Among these, the epoxy resin is preferably a naphthalene type or an arylalkylene type epoxy resin. By using a naphthalene type or arylalkylene type epoxy resin, moisture-absorbing solder heat resistance (solder heat resistance after moisture absorption) and flame retardancy can be improved in the cured resin layers 3 and 4 (obtained substrate). . As naphthalene type epoxy, DIC Corporation's HP-4700, HP-4770, HP-4032D, HP-5000, HP-6000, Nippon Kayaku Co., Ltd. NC-7300L, Nippon Steel Chemical Co., Ltd. ESN-375 manufactured by Nippon Kayaku Co., Ltd., NC-3000, NC-3000L, NC-3000-FH manufactured by Nippon Kayaku Co., Ltd., NC manufactured by Nippon Kayaku Co., Ltd. -7300L, ESN-375 manufactured by Nippon Steel Chemical Co., Ltd. The arylalkylene type epoxy resin means an epoxy resin containing one or more combinations of an aromatic group and an alkylene group such as methylene in the repeating unit, and is excellent in heat resistance, flame retardancy, and mechanical strength. In order to deal with a halogen-free wiring board, it is preferable to use an epoxy resin containing substantially no halogen.

  The cyanate resin can be obtained, for example, by reacting a halogenated cyanide compound with phenols or naphthols, and prepolymerizing by a method such as heating as necessary. Moreover, the commercial item prepared in this way can also be used.

  Examples of the cyanate resin include novolak-type cyanate resin, bisphenol A-type cyanate resin, bisphenol E-type cyanate resin, bisphenol-type cyanate resin such as tetramethylbisphenol F-type cyanate resin, and naphthol aralkyl-type cyanate resin. . Of these, one or more can be used.

  The cyanate resin preferably has two or more cyanate groups (—O—CN) in the molecule. For example, 2,2′-bis (4-cyanatophenyl) isopropylidene, 1,1′-bis (4-cyanatophenyl) ethane, bis (4-cyanato-3,5-dimethylphenyl) methane, 3-bis (4-cyanatophenyl-1- (1-methylethylidene)) benzene, bis (4-cyanatophenyl) thioether, bis (4-cyanatophenyl) ether, 1,1,1-tris (4 -Cyanatophenyl) ethane, tris (4-cyanatophenyl) phosphite, bis (4-cyanatophenyl) sulfone, 2,2-bis (4-cyanatophenyl) propane, 1,3-, 1,4 -, 1,6-, 1,8-, 2,6- or 2,7-dicyanatonaphthalene, 1,3,6-tricyanatonaphthalene, 4,4-dicyanatobiphenyl, and phenol novolac Type, cresol novolac type, dicyclopentadiene type and other polyhydric phenols and cyanate resin obtained by reaction with cyanogen halide, naphthol aralkyl type polyvalent naphthols and cyanate obtained by reaction with cyanogen halide Either resin or the like can be used. Among these, phenol novolac type cyanate resin is excellent in flame retardancy and low thermal expansion, and 2,2-bis (4-cyanatophenyl) isopropylidene and dicyclopentadiene type cyanate resin are used for controlling the crosslinking density, Excellent moisture resistance reliability. In particular, a phenol novolac type cyanate resin is preferred from the viewpoint of low thermal expansion. Furthermore, other cyanate resins may be used alone or in combination of two or more, and are not particularly limited.

  The said cyanate resin may be used independently, can also use together cyanate resin from which a weight average molecular weight differs, or can also use together the said cyanate resin and its prepolymer.

  By using these cyanate resins, it is possible to effectively exhibit heat resistance and flame retardancy.

  Moreover, the said curable resin can also be used in combination of 2 or more types. For example, when the epoxy resin is used as a curable resin, the cyanate resin can be used in combination for improving flame retardancy, and the maleimide compound is used in combination for improving heat resistance. be able to. Furthermore, when the cyanate resin is used as the curable resin, the epoxy resin can be used in combination for further improving heat resistance and flame retardancy.

  Although content of curable resin is not specifically limited, It is preferable that it is 5-70 mass% of the whole resin composition, and it is more preferable that it is 10-50 mass%. When the content of the curable resin is less than the lower limit, depending on the type of the curable resin, the viscosity of the varnish of the resin composition may be too low, and it may be difficult to form the laminated sheet 40B. . On the other hand, when the content of the curable resin exceeds the upper limit, the amount of other components is too small, and the mechanical strength of the laminated sheet 40B may be reduced depending on the type of the curable resin.

  Moreover, it is preferable that a resin composition contains an inorganic filler. Thereby, even if the prepreg is thinned (for example, a thickness of 35 μm or less), a substrate having excellent mechanical strength can be obtained. Furthermore, it is possible to improve the low thermal expansion of the substrate.

  Examples of the inorganic filler include talc, alumina, glass, silica such as fused silica, mica, aluminum hydroxide, magnesium hydroxide and the like. Further, depending on the purpose of use of the machine filler, a crushed or spherical one is appropriately selected. Among these, from the viewpoint of excellent low thermal expansion, the inorganic filler is preferably silica, and more preferably fused silica (particularly spherical fused silica).

  In addition to the components described above, the resin composition may contain other components as necessary within a range that does not impair the effects of the present invention. Other components include, for example, thickeners such as olben and benton, silicone, fluorine and polymer antifoaming agents or leveling agents, adhesion imparting agents such as coupling agents, flame retardants, phthalocyanine blue And colorants such as phthalocyanine green, iodine green, disazo yellow, carbon black, anthraquinones, and the like.

<Laminated sheet manufacturing equipment>
Next, the manufacturing apparatus 30 for manufacturing the laminated sheet 40B described above will be described.
An outline of the manufacturing apparatus 30 will be described with reference to FIGS.
This manufacturing apparatus 30 is a laminate (laminated sheet) in which a sheet (metal layer) 12 is temporarily bonded to at least one of the front and back surfaces of a prepreg composed of resin layers 3 and 4 and a fiber base material 2. An apparatus 30A (see FIG. 2) for manufacturing 40A, a cutting apparatus 30B (see FIG. 8) for cutting the laminated sheet 40A, and a curing apparatus 30C (see FIG. 9) for curing the cut laminated sheet 40A are provided.

The laminated sheet manufacturing apparatus 30 will be described in detail.
As shown in FIGS. 2 and 3, the laminated sheet manufacturing apparatus 30 includes an apparatus 30 </ b> A that manufactures a laminated sheet 40 </ b> A.
The apparatus 30A is configured to replace the resin layer of a sheet (for example, the sheet 5a) including a thermosetting resin layer (for example, the resin layer 3) and the metal layer 12 provided on the resin layer with respect to the fiber base material 2. A laminating means 70 which is brought into contact with at least one of the front surface and the back surface to laminate the sheet and the fiber base material 2 to obtain a laminated sheet 40A;
First heating means 60 for heating the laminated sheet 40A to advance the impregnation of the resin layer into the fiber base material 2, and heating the laminated sheet 40A to impregnate the resin layer into the fiber base material 2 And second heating means 90 for advancing.
Note that the laminated sheet 40A is conveyed along its longitudinal direction.

  As illustrated in FIG. 3, the stacking unit 70 includes a housing 75, first rollers 71 a and 71 b, second rollers 72 a and 72 b and third rollers 73 a and 73 b housed in the housing 75, and a housing 75. Pressure reducing means 76 for reducing the pressure inside. Hereinafter, the structure of each part is demonstrated.

As shown in FIG. 4, the housing 75 has, for example, a box shape having a pair of wall portions 751 arranged to face each other with a space therebetween. Although it does not specifically limit as a constituent material of the wall part 751, For example, various metals, such as iron, stainless steel, and aluminum, or the alloy containing these is mentioned. In addition to such a metal material, for example, a resin material such as polyethylene or polytetrafluoroethylene can be used as a constituent material of the wall portion 751.
Here, the wall 751 is preferably a flat plate, but is not limited thereto. The first rollers 71a and 71b, the second rollers 72a and 72b, and the third rollers 73a and 73b form a cylindrical body that is open at both end surfaces along the sheet conveying direction. The wall part 751 should just close the said opening of this cylindrical body. It is particularly preferable that the pair of wall portions 751 span the rollers 71a, 71b, 72a, 72b, 73a, 73b.

  Between the two wall portions 751 of the housing 75, first rollers 71a and 71b, second rollers 72a and 72b, and third rollers 73a and 73b are respectively constructed. These rollers have rotation axes parallel to each other. And these rollers are connected with the motor (not shown) via the gear mechanism (not shown) in which many gearwheels are arrange | positioned, for example. And when this motor operates, the motive power will be transmitted through a gear mechanism, and each roller will rotate, respectively. Needless to say, the driving of each roller is not limited to a gear mechanism, and if necessary, a motor may be connected to each roller and driven.

  These rollers have the same configuration except that the thicknesses are different. Hereinafter, although the structure of the 1st roller 71a is demonstrated typically, another roller is also the same structure.

  As shown in FIG. 4, the first roller 71 a has a columnar outer shape, and includes a main body 711 located at an intermediate portion in the longitudinal direction and shafts 712 located at both ends of the main body 711. It is configured. Each shaft 712 has an outer diameter smaller than the outer diameter of the main body 711.

  In the first roller 71 a, each shaft 712 is inserted into a bearing 771 installed on the wall 751, and is supported by the wall 751 so as to be rotatable by the bearing 771.

  In the present embodiment, the first roller 71a is solid, but is not limited thereto, and may be, for example, a hollow body. In the case of using a hollow body, it is more preferable because a heating medium can be circulated through each roller as necessary to heat the roller. The heat medium in this case is not particularly limited, and examples thereof include water and oil.

  Moreover, it does not specifically limit as a constituent material of the 1st roller 71a, For example, the material quoted by the constituent material of the wall part 751 can be used. The outer peripheral surface 711A of the main body 711 of the first roller 71a may be subjected to a process for preventing the outer peripheral surface 711A from being worn. An example of this treatment is a method of forming a DLC (Diamond Like Carbon) film on the outer peripheral surface 711A. Further, as the constituent material of the first roller 71a, various rubber materials such as nitrile rubber, butyl rubber, urethane rubber, silicone rubber, and fluorine rubber are used in addition to the materials mentioned as the constituent material of the wall 751. be able to.

  The first roller 71a and the first roller 71b are arranged in parallel to each other in the horizontal direction, and the outer peripheral surfaces 711A of the main body 711 are in contact with each other via the fiber substrate 2 (pressure contact). (See FIG. 3). And if the 1st roller 71a and the 1st roller 71b rotate, the elongate fiber base material 2 can be conveyed between these from the left side in FIG. Thereby, the sheet-like long fiber base material 2 will be conveyed in the space S mentioned later.

The second roller 72a and the second roller 72b are arranged at positions different from the first rollers 71a and 71b, that is, in front of the fiber base 2 in the conveying direction (downstream side) with respect to the first rollers 71a and 71b. Has been. The second roller 72a and the second roller 72b are arranged in parallel to each other in the horizontal direction, and the outer peripheral surfaces 711A of the main body 711 are the fiber base material 2, the first resin layer 3, and the second resin layer. 4 are in contact (pressure contact) with each other. And if the 2nd roller 72a and the 2nd roller 72b rotate, the 1st resin layer 3 and the 2nd resin layer 4 can each be crimped | bonded to the fiber base material 2 between these (refer FIG. 3). ). In this case, as described above, it is possible to perform thermocompression bonding by circulating a heat medium through the second rollers 72a and 72b. Thereby, the adhesiveness of the 1st resin layer 3 and the 2nd resin layer 4 with respect to the fiber base material 2 improves.
In addition, by using the second rollers 72a and 72b as heating rollers, the fiber base material 2 can be easily impregnated with the first resin layer 3 and the second resin layer 4. The temperature of the second rollers 72a and 72b is preferably higher than the melting temperature of the resin layers 3 and 4.
The laminated sheet 40A is fed out of the space S described later by the second rollers 72a and 72b. Here, it is preferable that the laminated sheet 40A is sent out in an atmosphere of atmospheric pressure or higher by the second rollers 72a and 72b. In the present embodiment, the downstream side of the second rollers 72a and 72b in the sheet conveying direction is atmospheric pressure, and the laminated sheets 40A are conveyed under atmospheric pressure by the second rollers 72a and 72b.

The third rollers 73a and 73b are arranged with the fiber base material 2 interposed therebetween. The third roller 73a is on the downstream side in the sheet conveying direction of the first roller 71a disposed on one surface side (front surface side) of the fiber base material 2, and is on one surface side (front surface side) of the fiber base material 2 ) Arranged on the upstream side in the sheet conveying direction of the second roller 72a.
The third roller 73b is on the downstream side in the sheet conveyance direction of the first roller 71b disposed on the other surface side (back surface side) of the fiber base material 2, and the other surface side (back surface side) of the fiber base material 2 ) Arranged on the upstream side in the sheet conveying direction of the second roller 72b.
The third roller 73a and the third roller 73b are spaced apart from each other in the vertical direction (vertical direction), and are opposed to each other in parallel in the horizontal direction. And if the 3rd roller 73a rotates, the support base 51 can be peeled from the 1st resin layer 3 of the 1st sheet | seat 5a (refer FIG. 3). Similarly, when the third roller 73b rotates, the support base 51 can be peeled from the second resin layer 4 of the second sheet 5b (see FIG. 3).

  Further, the third roller 73a has an outer peripheral surface 711A of the main body portion 711 on an outer peripheral surface 711A of the main body portion 711 of the first roller 71a and an outer peripheral surface 711A of the main body portion 711 of the second roller 72a. It is in contact. On the other hand, the third roller 73b has an outer peripheral surface 711A of the main body 711 on an outer peripheral surface 711A of the main body 711 of the first roller 71b and an outer peripheral surface 711A of the main body 711 of the second roller 72b. It is in contact. With such an arrangement, the manufacturing apparatus 30A is surrounded by each wall 751 of the housing 75, the first rollers 71a and 71b, the second rollers 72a and 72b, and the third rollers 73a and 73b. A space S is formed. The space S is depressurized by the operation of the depressurizing means 76 (see FIG. 3).

  Again, as shown in FIG. 4, both ends of each main body portion 711 of each of the first rollers 71a and 71b (the same applies to the second rollers 72a and 72b and the third rollers 73a and 73b), and each wall portion 751. A sealing material 77 is interposed between the two. Each sealing material 77 is formed of a ring-shaped elastic body, and is inserted into a ring-shaped recess 751A formed in the wall 751 in a compressed state. Thereby, the airtightness of the space S is reliably maintained. Therefore, when the space S is decompressed by the decompression means 76, the decompression is performed quickly and reliably.

  The constituent material of the sealing material 77 is not particularly limited. For example, natural rubber, isoprene rubber, butadiene rubber, styrene-butadiene rubber, nitrile rubber, chloroprene rubber, butyl rubber, acrylic rubber, ethylene-propylene rubber, hydrin rubber, urethane rubber. , Various rubber materials such as silicone rubber and fluoro rubber (especially those vulcanized), styrene, polyolefin, polyvinyl chloride, polyurethane, polyester, polyamide, polybutadiene, trans polyisoprene, Various thermoplastic elastomers such as fluororubber-based and chlorinated polyethylene are listed, and one or more of these can be used in combination.

  As shown in FIG. 3, the first rollers 71a and 71b, the second rollers 72a and 72b, and the third rollers 73a and 73b have different outer diameters (sizes) of the main body 711. . In the present embodiment, the magnitude relationship is (third roller) <(first roller) <(second roller). Further, the size of each of the first rollers 71a and 71b, the second rollers 72a and 72b, and the third rollers 73a and 73b is arbitrary, but for example, a sheet material having flexibility in the rollers It is preferable that the sheet material is as small as possible without causing wrinkles in the sheet material. Specifically, the diameter is preferably 75 to 300 mm, and more preferably 100 to 200 mm.

  Further, assuming a triangle formed by connecting the centers of the first roller 71a, the second roller 72a, and the third roller 73a, an angle with the center of the third roller 73a of the triangle as a vertex Is preferably greater than 60 ° and less than 180 °. The same applies to the triangle formed by connecting the centers of the first roller 71b, the second roller 72b, and the third roller 73b.

As shown in FIG. 5, the decompression unit 76 includes a pump 761 and a connection pipe 762 that connects the pump 761 and an opening 751 </ b> B formed in each wall 751. The pump 761 is installed outside the housing 75, and for example, a vacuum pump is applied.
The decompression unit 76 sets the pressure inside the space S surrounded by the rollers to be lower than the area outside the space S. By driving the decompression means 76, the atmospheric pressure in the space S is higher than the first roller 71a, 71b in the upstream area in the sheet conveying direction and the second roller 72a, 72b in the downstream area in the sheet conveying direction. Lower. A region upstream of the first rollers 71a and 71b and upstream of the first rollers 71a and 71b in the sheet conveying direction is equal to or higher than atmospheric pressure (in this embodiment, under atmospheric pressure).
Similarly, with the second rollers 72a and 72b as a boundary, the area downstream of the second rollers 72a and 72b in the sheet conveying direction is equal to or higher than atmospheric pressure (in this embodiment, under atmospheric pressure).

  Each connecting pipe 762 is a hard pipe made of a metal material such as stainless steel.

  Each opening 751B opens toward the space S and communicates with the space S. In the configuration shown in FIG. 5, the openings 751 </ b> B are formed in both the wall portions 751. However, the present invention is not limited to this. For example, the opening 751 </ b> B may be formed only in one wall portion 751. .

  Then, by operating the pump 761, the gas (air G) in the space S can be sucked from each opening 751B, and thus the space S can be decompressed. Further, as a result, a force that causes the adjacent rollers to approach each other is generated and further pressed against each other, so that the airtightness of the space S is more reliably maintained.

FIG. 10 shows a cross-sectional view of the fiber base 2 and the resin layers 3 and 4 in the DD direction of FIG. The width dimension in the direction orthogonal to the conveyance direction of the fiber base material 2 is smaller than the width dimension in the direction orthogonal to the conveyance direction of the first resin layer 3 and the second resin layer 4.
As described above, the fiber base 2, the first resin layer 3, and the second resin layer 4 are pressure-bonded by the pair of second rollers 72a and 72b. At this time, one end in the width direction of the first resin layer 3 and one end in the width direction of the second resin layer 4 are melted and pressure-bonded (thermocompression bonding), and the first resin layer The other end in the width direction of 3 and the other end in the width direction of the second resin layer 4 are melted and subjected to pressure bonding (thermocompression bonding). Thereby, the edge parts of the resin layers 3 and 4 are directly joined to form a joined part, and the fiber base material 2 is included in the first resin layer 3 and the second resin layer 4. That is, both end portions in the width direction of the laminated sheet 40A are in a sealed state.
The fiber base material 2 is a porous material in which a plurality of holes are formed. The holes formed in the fiber base 2 communicate with each other in the sheet conveying direction via other holes, and further communicate with the front and back surfaces of the fiber base 2. Therefore, even if it is the fiber base material 2 located in the space S exterior, the inside will be connected to the space S. The gas (air) inside the fiber base 2 located outside the space S is sucked by the decompression means through the holes and the space S inside the fiber base 2.

Next, with reference to FIGS. 2 and 3, the first heating unit 60 disposed on the downstream side of the stacking unit 70 in the sheet conveying direction will be described.
A laminated sheet 40A composed of the metal layer 12, the resin layer 4, the fiber base 2, the resin layer 3, and the metal layer 12 is continuously sent out from the rollers 72a and 72b of the laminating means 70. Here, the resin layers 3 and 4 are pressure-bonded to the fiber base material 2 by the rollers 72 a and 72 b, and at this time, a part of the resin layers 3 and 4 is impregnated inside the fiber base material 2. However, the inside of the fiber base 2 is not completely filled with the resin layers 3 and 4 by the rollers 72a and 72b.
The laminated sheet 40A is continuously supplied to the first heating means 60, and the laminated sheet 40A is heated to further advance the impregnation of the resin layers 3 and 4 into the fiber substrate 2.
The first heating unit 60 includes, for example, at least a pair of heating rollers 61a and 61b. In the present embodiment, the first heating means 60 has a plurality of pairs of heating rollers 61a and 61b. The laminated sheet 40A is supplied between the heating rollers 61a and 61b, and the laminated sheet 40A is sandwiched between the heating rollers 61a and 61b and heated.
The heating rollers 61a and 61b also have a function of conveying the laminated sheet 40A by rotating.
Here, the first heating unit 60 includes a heating roller. However, the first heating unit is not limited thereto, and the first heating unit includes a heating unit such as a heater that extends along the conveyance direction of the laminated sheet. You may have.
The laminated sheet 40A is heated by the first heating means 60 while being conveyed.
The heating temperature for heating the laminated sheet 40A by the first heating means 60 is preferably lower than the heating temperature by the second heating means 90 described later. Moreover, it is preferable that the heating temperature at the time of heating the laminated sheet 40A is lower than the heating temperature by the rollers 72a and 72b. For example, the heating temperature of the laminated sheet 40A by the first heating means 60 is preferably 80 to 180 ° C, and the heating temperature of the laminated sheet 40A by the second heating means 90 is 80 to 200 ° C. preferable. In the 1st heating means 60, the impregnation to the fiber base material 2 inside of the resin layers 3 and 4 is mainly advanced. The laminated sheet 40A is heated by the first heating means 60 at a temperature lower than the heating temperature in the second heating means 90, thereby preventing the resin layers 3 and 4 from being excessively hardened and impregnating. Is progressing.
On the other hand, the second heating means 90 is heated at a temperature higher than that of the first heating means 60 to advance the curing of the resin layers 3 and 4 to adjust the degree of curing and to achieve a desired curing rate. And However, in the second heating means 90, the impregnation of the resin layers 3 and 4 into the fiber base 2 may be advanced.

Furthermore, when the laminated sheet 40A is heated by the first heating means 60, it is preferable that a predetermined tension is applied to the laminated sheet 40A in the conveying direction. However, when the laminated sheet 40A is heated by the first heating means 60, the tension applied to the laminated sheet 40A is the tension applied to the laminated sheet 40A when the laminated sheet 40A is heated by the second heating means 90. Is preferably larger. When the laminated sheet 40A is heated by the first heating means 60, the tension applied to the laminated sheet 40A is, for example, 50 to 500N, and when the laminated sheet 40A is heated by the second heating means 90, the laminated sheet 40A is laminated. The tension applied to the sheet 40A is preferably 10 to 200N.
By doing in this way, the laminated sheet 40A can be heated by the first heating means 60, and the fiber layers 2 can be sufficiently impregnated with the resin layers 3 and 4.
On the downstream side of the first heating unit 60 in the sheet conveyance direction, a conveyance roller R1 for conveying the roller sent from the first heating unit 60 to the second heating unit 90 in the subsequent stage is disposed.

Further, as shown in FIG. 2, a second heating unit 90 is disposed on the downstream side of the first heating unit 60 in the laminated sheet conveying direction. The laminated sheet 40A heated by the first heating means 60 is heated by the second heating means 90. As shown in FIGS. 2 and 7, the second heating unit 90 includes a vertical heating furnace 91. In the present embodiment, the second heating means 90 includes a plurality of vertical heating furnaces 91. The laminated sheets 40 </ b> A are continuously supplied into the vertical heating furnace 91 by the transport rollers R <b> 2 and 3. In one vertical heating furnace 91, the laminated sheet 40A is conveyed from the lower side in the vertical direction toward the upper side. In addition, the laminated sheet 40A is conveyed from the upper side in the vertical direction toward the lower side in the other vertical heating furnace 91 by the conveying rollers R3 and R2.
The distance between the transport rollers R2 and R3 is, for example, about 5 m.
In each heating furnace 91, the laminated sheet 40A is conveyed along its longitudinal direction, and at least a pair of pressure rollers 92 (a plurality of pairs of pressure rollers in the present embodiment) press the laminated sheet 40A from the thickness direction. Is arranged.
The pressure roller 92 has a heater disposed therein, and pressurizes and heats the laminated sheet 40A.
In addition to the pressure roller 92, heating means such as a heater is disposed inside the heating furnace 91, and the laminated sheet 40A is heated by passing through the inside of the heating furnace 91.
In the present embodiment, the second heating unit 90 includes the vertical heating furnace 91. However, the second heating unit 90 is not limited to this, and may be a horizontal heating furnace. For example, the inside of a horizontal heating furnace may be conveyed while supporting the laminated sheet 40A from the back side by air.
Further, when the sheet 5a or the sheet 5b is provided only on one surface of the fiber base material 2, the pressure roller 92 may not be provided, and the position of the pressure roller 92 is moved so that the fiber base material is moved. 2 may not be touched.
A take-up roller R4 is disposed downstream of the second heating unit 90 in the sheet conveying direction, and the laminated sheet 40A is taken up by the take-up roller R4.
In the present embodiment, the laminated sheet 40A is taken up by the take-up roller R4. However, the laminated sheet 40A may be cut into a predetermined length without being taken up.
The resin layers 3 and 4 of the laminated sheet 40A manufactured by the manufacturing apparatus 30A are both semi-cured and in a B stage state. In the laminated sheet 40A which is a prepreg manufactured by the manufacturing apparatus 30A, the inside of the fiber base material 2 is completely embedded by the resin layers 3 and 4. However, the inside of the fiber base 2 may not be completely embedded in the resin layers 3 and 4, and a void may be formed inside the fiber base 2.

Next, the cutting device 30B will be described with reference to FIG.
This cutting device 30B includes a flattening means 81 for flattening the laminated sheet 40A, and a cutting means 82 for cutting the laminated sheet 40A into a predetermined dimension.
The flattening means 81 is a pair of rollers 811 arranged with the laminated sheet 40A delivered from the take-up roller interposed therebetween, and corrects the winding of the laminated sheet 40A to flatten the laminated sheet 40A. The planarizing means 81 is continuously supplied with the laminated sheet 40A along its longitudinal direction.
A cutting means 82 is disposed downstream of the flattening means 81 in the laminated sheet conveying direction. The cutting means 82 has a blade and cuts the laminated sheet 40A into a predetermined dimension.
The laminated sheet 40A cut by the cutting means 82 is conveyed to the mounting table D by the belt conveyor B1. The resin layers 3 and 4 of the laminated sheet 40A cut in this way are both semi-cured and in a B stage state.

Next, the curing device 30C will be described with reference to FIG. The curing device 30C cures the resin layers 3 and 4 of the laminated sheet 40A cut by the cutting device 30B to obtain a laminated sheet 40B.
As shown in FIG. 9A, the curing device 30C heats and cuts the cut laminated sheet 40A. At this time, the laminated sheet 40A is heated and cured without pressing the laminated sheet 40A from the outside. Specifically, the curing device 30C includes a heating furnace 85, a heating unit that is a heater 86 disposed in the heating furnace 85, and a jig 87 that suspends the laminated sheet 40A.
The jig 87 is for suspending the laminated sheet 40A so that the front and back surfaces of the laminated sheet 40A are parallel to the vertical direction. The laminated sheet 40A is attached to the support member 88 extending in the horizontal direction by the jig 87 and is in a suspended state. Then, the laminated sheet 40 </ b> A is heat-cured with the jig 87 holding the end of the laminated sheet 40 </ b> A. Thereby, the laminated sheet 40A is completely cured (C stage), and the metal layer 12 and the resin layers 3 and 4 are finally bonded. Thereby, the laminated sheet 40B is obtained.
A plurality of laminated sheets 40A are suspended in the heating furnace 85, and the plurality of laminated sheets 40A are heat-cured simultaneously. The laminated sheet 40B is taken out from the heating furnace 85 and cooled. As shown in FIG. 9B, cooling is preferably performed by suspending the laminated sheet 40B so that the front and back surfaces thereof are parallel to the vertical direction.

<Manufacturing method>
Next, the manufacturing method of the lamination sheet 40B by the lamination sheet manufacturing apparatus 30 is demonstrated.
First, an outline of the manufacturing method will be described.
In the manufacturing method of the present embodiment, a prepreg impregnated with a thermosetting resin material with respect to the fiber substrate 2 and a sheet (metal layer) temporarily bonded to at least one of the front and back surfaces of the prepreg 12) and a step of preparing a laminated body (laminated sheet 40A) and heating the thermosetting resin layer by heating the laminated body without applying pressure to the sheet and the prepreg. And a main bonding step.

Next, the manufacturing method will be described in detail.
First, the laminated sheet 40A is manufactured by the apparatus 30A.
First, sheets 5a and 5b are prepared.
A long metal layer 12 is prepared, and a resin varnish serving as the first resin layer 3 is applied to the metal layer 12. And it is made to dry with a drying apparatus and the 1st resin layer 3 of desired thickness is formed.
The first resin layer 3 is long and extends together with the metal layer 12.
Further, a support base 51 that covers the first resin layer 3 is laminated on the first resin layer 3.
Thereby, the elongate sheet | seat 5a is obtained.
The sheet 5b is also prepared by the same method. A long metal layer 12 is prepared, and a resin varnish to be the second resin layer 4 is applied to the metal layer 12. And it is made to dry with a drying apparatus and the 2nd resin layer 4 of desired thickness is formed. The second resin layer 4 is long and extends together with the metal layer 12. Further, a support base 51 that covers the second resin layer 4 is laminated on the second resin layer 4.
In this embodiment, a resin varnish that becomes the first resin layer 3 (or a resin varnish that becomes the second resin layer 4) is applied on the metal layer 12 in advance, and the resin varnish is dried to obtain the first resin layer. 3 (second resin layer 4) is formed. Therefore, compared with the case where the metal layer 12 and the resin layer are bonded together by pressure, the adhesion between the resin layer and the metal layer can be enhanced.

Next, prior to the rotation of the first rollers 71a and 71b, the second rollers 72a and 72b, and the third rollers 73a and 73b, the decompression means 76 is operated to suck the gas in the space S. Then, the space S is depressurized (see FIG. 3).
The atmospheric pressure in the space S is, for example, 800 Pa or less and 100 Pa or more.

  As shown in FIG. 3, when the first roller 71a and the first roller 71b rotate, the fiber base material 2 is sent out into the space S from these rollers (continuously supplied).

Further, when the second roller 72a and the third roller 73a rotate, the first sheet 5a is sent out into the space S from between these rollers (continuously supplied).
Here, as described above, the first sheet 5a is formed by laminating the support base 51, the first resin layer 3, and the metal layer 12 in this order.
In the first sheet 5 a, the support base 51 is wound (pulled) along the outer peripheral surface of the third roller 73 a, whereby the support base 51 is peeled from the first resin layer 3. The first resin layer 3 from which the support base 51 has been peeled gradually approaches the fiber substrate 2 along the second roller 72a. Further, the peeled support base 51 is sent out in a direction different from that of the second rollers 72a and 72b by the first roller 71a and the third roller 73a. Specifically, it is sent out from between the first roller 71a and the third roller 73a toward the outside (outside the space S). The first resin layer 3 is in a B-stage state and is in a solid, semi-solid, or liquid state.

Further, when the second roller 72b and the third roller 73b rotate, the second sheet 5b is sent out from between these rollers into the space S (continuously supplied). Here, as described above, the second sheet 5b is formed by laminating the support base 51, the second resin layer 4, and the metal layer 12 in this order.
In the second sheet 5 b, the support base 51 is wound around the third roller 73 b, whereby the support base 51 is peeled from the second resin layer 4. The second resin layer 4 from which the support base 51 has been peeled gradually approaches the fiber substrate 2 along the second roller 72b. The peeled support base 51 is sent out in a direction different from that of the second rollers 72a and 72b by the first roller 71b and the third roller 73b. Specifically, the sheet is fed outward from between the first roller 71b and the third roller 73b.
The second resin layer 4 is in a B-stage state and is in a solid, semi-solid, or liquid state.

  As described above, the support base 51 can be peeled in the space S immediately before (before) the first resin layer 3 and the second resin layer 4 are pressure-bonded to the fiber base 2. In addition to preventing the resin layer from being obstructed, the support base 51 can protect each resin layer until just before the pressure bonding.

And the fiber base material 2, the 1st resin layer 3, the metal layer 12 provided in the 1st resin layer 3, the 2nd resin layer 4, and the metal layer 12 provided in the 2nd resin layer 4 are The second roller 72a and the second roller 72b are collectively passed. These are conveyed along the longitudinal direction. At this time, as shown in FIG. 6, the first resin layer 3 is pressed against the fiber substrate 2 from above by the pressure contact force (contact force) F1 between the second roller 72a and the second roller 72b. In addition, the second resin layer 4 is pressed against the fiber base material 2 from below. Thereby, the laminated sheet 40A is obtained. The laminated sheet 40A is continuously discharged from between the second roller 72a and the second roller 72b and supplied to the first heating means 60.
Here, the fiber substrate 2 or the like is continuously supplied or discharged is intended to exclude a fiber substrate or the like that is intermittently supplied or discharged, such as a single wafer type. It is. For example, the purpose is to exclude a state in which the fiber base material 2 or the like is present in the space S and a state in which the fiber base material 2 is not present alternately in a short period of time. However, you may stop conveyance of the fiber base material 2 grade | etc., As needed.

  In the manufacturing apparatus 30A, the space to be depressurized is as small as possible as a space S surrounded by the first rollers 71a and 71b, the second rollers 72a and 72b, and the third rollers 73a and 73b. can do. Thereby, 30 A of manufacturing apparatuses become a small thing. Further, when the decompression means 76 is operated, the decompression can be performed quickly. Further, high vacuum can be achieved.

  Further, as described above, the space S is decompressed by the operation of the decompression means 76. Thereby, as shown in FIG. 6, the decompression force F <b> 2 generated in the space S is the press of the first resin layer 3 to the fiber base 2 and the press of the second resin layer 4 to the fiber base 2. Can assist.

  Further, when the fiber base material 2 and the first resin layer 3 are joined, even if air is accumulated between them, the air can be pushed out by the pressure contact force F1, and thus the joining can be performed while the air remains. This can be reliably prevented (the same applies when the fiber base material 2 and the second resin layer 4 are joined).

The pressing by the pressure contact force F1 and the pressing by the pressure reduction force F2 can be combined to strongly press the resin layers 3 and 4 to the fiber substrate 2. Thereby, the resin layers 3 and 4 can be impregnated inside the fiber base material 2. In addition, by using the second roller 72a and the second roller 72b as heating rollers, the resin layers 3 and 4 can be easily impregnated into the fiber base 2.
Furthermore, by reducing the pressure in the space S, the gas inside the fiber base 2 is sucked, and voids are less likely to occur in the resin layer impregnated in the fiber base 2.
The second roller 72a and the second roller 72b impregnate part of the resin layers 3 and 4 into the fiber base 2 but do not impregnate completely. In this step, although the resin layers 3 and 4 impregnate the fiber base material 2, the fiber base material 2 inside the laminated sheet 40 </ b> A sent out from the second rollers 72 a and 72 b is a fiber base located in the space S. It communicates with the inside of the material 2.
Moreover, the resin sheet 3 and 4 is impregnated into the fiber base material 2 by the second roller 72a and the second roller 72b, whereby the laminated sheet 40B having a desired degree of impregnation can be obtained.
That is, it is possible to prevent the impregnation of the resin layers 3 and 4 from being insufficient after heating by the second heating means 90.

The laminated sheet 40A is continuously fed out of the space S and supplied to the first heating means 60 by the second roller 72a and the second roller 72b.
As described above, the first heating means 60 is heated and pressurized by the heating rollers 61a and 61b. Thereby, impregnation into the fiber base material 2 of the resin layers 3 and 4 will advance. Further, the resin layers 3 and 4 are also cured by the first heating means 60. However, even after the heating by the first heating means 60 is completed, the resin layers 3 and 4 are in a B-stage state. Curing of the resin layers 3 and 4 is advanced by heating the laminated sheet 40 </ b> A by the first heating means 60.

As described above, the fiber base 2, the first resin layer 3, and the second resin layer 4 are pressure-bonded by the pair of second rollers 72a and 72b. At this time, one end in the width direction of the first resin layer 3 and one end in the width direction of the second resin layer 4 are thermocompression bonded, and the other in the width direction of the first resin layer 3. And the other end in the width direction of the second resin layer 4 are thermocompression bonded. The end portions in the width direction of the resin layers 3 and 4 are melt-bonded to each other so that the fiber base material 2 is included in the first resin layer 3 and the second resin layer 4. That is, both ends in the width direction of the laminated sheet 40A are sealed (see FIG. 10).
The fiber base material 2 is a porous material in which a plurality of holes are formed. The holes formed in the fiber base 2 communicate with each other in the sheet conveying direction via other holes, and further communicate with the front and back surfaces of the fiber base 2. Therefore, even if it is the fiber base material 2 located in the space S exterior, the inside will be connected to the space S. The gas inside the fiber base 2 located outside the space S is sucked by the decompression means through the holes inside the fiber base 2 and the space S. During heating by the first heating means 60, the inside of the fiber base material 2 of the laminated sheet 40 </ b> A being heated communicates with the inside of the fiber base material 2 existing inside the space S. Therefore, by reducing the pressure inside the space S, the inside of the fiber base 2 of the laminated sheet 40A heated by the first heating means 60 is reduced via the fiber base 2 located in the space S. It becomes. That is, in the first heating means 60, the impregnation of the fiber base 2 with the resin layers 3 and 4 proceeds while the gas inside the fiber base 2 is sucked into the decompression means 76. Thereby, when the resin layers 3 and 4 impregnate the fiber base material 2 inside, it can suppress that gas remains in the fiber base material 2 inside, and that a void generate | occur | produces in the fiber base material 2 can be prevented. Can be suppressed.
In addition to this, in the laminated sheet 40A, the end surface on the conveyance direction side of the fiber base material 2 is covered with the resin layers 3 and 4 and is not exposed. Therefore, it is prevented that gas flows into the fiber base material 2 of the laminated sheet 40A from the end face side of the fiber base material 2 of the laminated sheet 40A, and the inside of the fiber base material 2 of the laminated sheet 40A can be reliably decompressed. . Also by this, when the laminated sheet 40A is heated by the first heating means 60 and the resin layers 3 and 4 are impregnated into the fiber base material 2, the gas remains in the fiber base material 2. Can be suppressed.

  Furthermore, since the inside of the fiber base material 2 of the laminated sheet 40A is depressurized, the resin layers 3 and 4 are thereby pulled to the inside of the fiber base material 2, and the resin layers 3 and 4 are brought into the fiber base material 2 inside. The impregnation of will proceed further.

Furthermore, although the inside of the fiber base material 2 inside the laminated sheet 40A is depressurized, the laminated sheet 40A exists in an atmosphere of atmospheric pressure or higher (in this embodiment, under atmospheric pressure). Thereby, the laminated sheet 40A heated by the first heating means 60 is subjected to a force of atmospheric pressure or more from the outside. Also by this, the impregnation of the resin layers 3 and 4 into the fiber base 2 can be promoted.
In addition, the resin layers 3 and 4 are sufficiently provided inside the fiber base 2 so that the first heating means 60 does not have a hole communicating with the end surface along the transport direction of the fiber base 2 inside the fiber base 2. To impregnate.

In the 1st heating means 60, impregnation of the resin layers 3 and 4 to the fiber base material 2 will advance, conveying laminated sheet 40A. Thereafter, the laminated sheet 40A passes through the first heating unit 60 and is conveyed to the second heating unit 90 by the conveyance roller R1. Next, the laminated sheet 40A is heated by the second heating means 90 (see FIGS. 2 and 7).
Specifically, the laminated sheet 40A is heated by the conveyance roller R2 while being conveyed upward in the vertical direction in one vertical heating furnace 91. Thereafter, the laminated sheet 40A is sent out from one vertical heating furnace 91, and then the laminated sheet 40A is sent into the other vertical heating furnace 91. The laminated sheet 40A is heated while being conveyed vertically downward in the other vertical heating furnace 91.
In this heating step, curing of the resin layers 3 and 4 proceeds while the laminated sheet 40A is being conveyed in the vertical heating furnace.
By configuring the second heating means 90 with the vertical heating furnace 91, the installation space for the manufacturing apparatus can be saved.

  Even after the heating by the second heating means 90 is completed, the resin layers 3 and 4 are in a B-stage state.

After the heating by the second heating means 90 is finished, as shown in FIG. 2, the laminated sheet 40A is wound around the take-up roller R4. Thus, the laminated sheet 40A is obtained. The above process is a process for preparing a laminated sheet 40A including a prepreg (consisting of the fiber base 2 and the resin layers 3 and 4) and the metal layer 12 temporarily bonded to the prepreg.
In the above steps, the resin layers 3 and 4 are cured by heating of the rollers 72a and 72b, the first heating unit 60, and the second heating unit 90, and the adhesive strength between the resin layer 3 and the metal layer 12 is increased. The adhesive strength between the layer 4 and the metal layer 12 is increased. Thereby, the laminated sheet 40A in which the metal layer 12 is temporarily bonded to the prepreg is obtained. In the above steps, the laminated sheet 40A is cut at the subsequent stage, and the metal layer 12 is temporarily bonded to the prepreg so that the metal layer 12 does not peel from the prepreg when the cut laminated sheet 40A is suspended.

Next, as shown in FIG. 8, the laminated sheet 40A is continuously supplied from the winding roller R4 to the apparatus 30B. And the lamination sheet 40A is pinched by the planarization means 81 of the apparatus 30B, and the lamination sheet 40A is planarized. Thereafter, the cutting sheet 82 cuts the laminated sheet 40A into a predetermined size.
Next, the end of the laminated sheet 40A is held by the jig 87 of the curing device 30C shown in FIG. 9A, and the plurality of laminated sheets 40A are suspended in the heating furnace 85. Then, the laminated sheet 40A is heat-cured in an unpressurized state without applying pressure from outside under atmospheric pressure. At the time of heat curing, the laminated sheet 40A is not sandwiched from the thickness direction and the direction orthogonal to the thickness direction.
The laminated sheet 40A is completely cured (C stage), and the metal layer 12 and the resin layers 3 and 4 are finally bonded. Thereby, the hardening body which is the lamination sheet 40B is obtained. The heating temperature of the laminated sheet 40A in this main bonding step is preferably less than the glass transition point of the laminated sheet 40B that is a cured body. By doing in this way, there exists an effect that the dimensional change at the time of a reflow process can be made small. Further, by heating the laminated sheet 40A below the glass transition point, discoloration of the resin layers 3 and 4 and the metal layer 12 and deterioration of the resin layers 3 and 4 can be suppressed. Note that a jig for fixing the laminated sheet 40A may be used in order to prevent the laminated sheet 40A from wobbling or warping when it is heat-cured.
However, from the viewpoint of reducing the residual stress generated inside the laminated sheet 40B, which is a cured body, it is preferable not to apply a load or tension exceeding the weight of the laminated sheet 40A.
The C stage is a case where almost no heat generation can be observed when heat-cured by DSC, and the curing rate is 90% or more.
In the present embodiment, the laminated sheet 40A is suspended in the heating furnace 85 to cure the laminated sheet 40A. By doing in this way, space saving of the space which hardens | cures the laminated sheet 40A can be achieved. Further, since the laminated sheet 40A is suspended, only the end portion of the laminated sheet 40A is in contact with the jig, and most of the front and back surfaces of the laminated sheet 40A are not in contact with the jig or the like. Therefore, it can prevent that the trace of the member which supports laminated sheet 40A arises in the front and back of laminated sheet 40A.

Thereafter, as shown in FIG. 9B, the laminated sheet 40B is taken out from the heating furnace 85 and cooled. When the curing rate of the resin layers 3 and 4 in this main bonding step is β and the curing rate of the resin layers 3 and 4 of the laminated sheet 40A in the step of preparing the laminated sheet 40A is α, β-α is 5% to 90%. Of these, β-α is preferably 20 to 80%.
The curing rate can be calculated by measuring the exothermic peak by DSC. Further, when calculating the curing rate, the curing rate of the resin layer in the state of the sheets 5a and 5b is set to 0%.
The laminated sheet 40B is obtained by the above process. The adhesive strength between the prepreg and the metal layer 12 in the laminated sheet 40B is such that the prepreg and the metal layer 12 in the laminated sheet 40A having the metal layer 12 temporarily bonded to the prepreg. Higher than the adhesive strength.
The adhesive strength here is peel strength, and can be measured according to the JIS C 6481 90-degree peeling method. Specifically, the measurement can be performed by peeling off the metal layer in the direction of 90 degrees with respect to the resin layer of the prepreg.
The peel strength in the laminated sheet 40A having the metal layer 12 temporarily bonded to the prepreg is preferably, for example, 0.2 to 0.4 N / mm ² , and the prepreg and the metal layer 12 in the laminated sheet 40B are adhesive strength, for example, is preferably 0.8~1.0N / mm ^2, preferably a 2 to 5 times the peel strength in the laminate sheet 40A described above.

In the present embodiment, the laminated sheet 40 </ b> A is heated without being pressurized, and the thermosetting resin layers 3 and 4 are cured.
Thereby, since the prepreg composed of the resin layers 3 and 4 and the fiber base material 2 is not pressurized, stress is less likely to be generated inside the prepreg, and the residual stress generated inside the laminated sheet 40B that is a cured body can be reduced. .
In the temporary bonding step, the laminated sheet 40A is pressurized to cure the thermosetting resin layers 3 and 4. At this time, residual stress due to pressurization is generated inside the laminated sheet 40A, but the residual stress is released because the laminated sheet 40A is heated again in this bonding step. As described above, in the main bonding step, the laminated sheet 40 </ b> A is heated and heated to advance the thermosetting resin layers 3 and 4. Residual stress generated in can be reduced.
In this embodiment, the curing rate of the resin layers 3 and 4 in the main bonding step is β, and the curing rate of the resin layers 3 and 4 of the laminated sheet 40A in the step of preparing the laminated sheet 40A is α. , Β-α is 5% to 90%. That is, the curing of the resin layers 3 and 4 proceeds relatively large in the main bonding step. Thus, when the prepreg is pressurized in the main bonding step where the curing proceeds relatively greatly, the force applied by the pressure tends to remain in the prepreg, but in the present embodiment, in the main bonding step Since the prepreg is not pressurized, it is difficult for stress to remain inside the prepreg, and the residual stress generated inside the laminated sheet 40B, which is a cured body, can be reliably reduced.
In such a laminated sheet 40B, since the residual stress is reduced, even if the resin layer is softened by heating and the residual stress is relaxed, the dimensional variation before and after heating is less likely to occur, and the sheet is highly reliable. It becomes.

  Next, the joint portion of the laminated sheet 40B manufactured as described above is cut as necessary. And the lamination sheet 40B obtained in this way can be used as a core material of a multilayer printed wiring board. In other words, the metal layer 12 of the laminated sheet 40B is selectively removed to form a circuit layer, and a prepreg or a resin layer is laminated so as to cover the circuit layer, whereby a multilayer printed wiring board can be obtained.

It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.
For example, in the above-described embodiment, the end of the laminated sheet 40A is gripped by the jig of the curing device 30C, the plurality of laminated sheets 40A are suspended in the heating furnace, and the laminated sheet 40A is heat-cured. It is not limited to. For example, the laminated sheet 40A may be heat-cured under atmospheric pressure while the cut laminated sheet 40A is placed on a belt conveyor and conveyed in a heating furnace. Also in this case, the laminated sheet 40A is cured without being pressurized from the outside.

Furthermore, in the said embodiment, the long resin layer 3 with a metal layer 12 and the long resin layer 4 with a metal layer 12 are crimped | bonded with respect to the long fiber base material 2, and a long metal layer is attached. Although the laminated sheet 40A which is a prepreg was manufactured, the present invention is not limited thereto, and for example, the fiber base 2 is impregnated with the resin layers 3 and 4 to manufacture the prepreg, and the metal layer 12 is applied to the prepreg. The laminated sheet 40A may be manufactured by pressure bonding.
However, when manufacturing the prepreg, the fiber base material 2 is impregnated with the first resin layer 3 and the second resin layer 4 in a varnish form. At this time, the fiber base material 2 is immersed in a tank filled with the varnish, Since it is necessary to pull up from this tank, it is necessary to apply very large tension to the fiber substrate 2. If the sheet 5a (5b) having a resin layer and a metal layer is prepared in advance and the fiber base material 2 is impregnated with the fiber base 2 as in this embodiment, the tension applied to the fiber base 2 is reduced. Is possible.

Furthermore, in the said embodiment, although the sheet-like metal layer 12 was provided in the resin layers 3 and 4, it is not restricted to this, The resin sheet may be provided in the resin layers 3 and 4. FIG. Furthermore, you may laminate | stack the prepreg different from the prepreg comprised by the resin layers 3 and 4 and the fiber base material 2 on the prepreg comprised by the resin layers 3 and 4 and the fiber base material 2. FIG. Then, a plurality of prepregs may be temporarily bonded to form a laminated body, and then heated to be non-pressurized for main bonding.
Further, for example, a metal layer 12 provided with a resin substrate may be used. In this case, the metal layer 12 is temporarily bonded to the resin layers 3 and 4 as in the above embodiment. In this case, a core material with a buildup layer in which a buildup layer is provided on a core material for a circuit board is obtained as a cured body.

  Moreover, in the said embodiment, although the inside of the space S enclosed by the roller was decompressed and the fiber base material 2 and the resin layers 3 and 4 with the metal layer 12 were laminated | stacked in the space S, it is restricted to this. It is not a thing. For example, the inside of the container may be decompressed, and the fiber base 2 and the resin layers 3 and 4 with the metal layer 12 may be laminated in the container.

  Moreover, in the said embodiment, although the fiber base material 2 and the sheet | seats 5a and 5b are elongate and the laminated sheet 40A was supplied continuously to the 1st heating means 60 grade | etc., It is restricted to this. is not. You may manufacture a laminated body by a single wafer type. For example, as described above, a container whose inside is depressurized is prepared, and a pinching member such as a pair of press plates is disposed in the container. And the laminated body of the fiber base material, the resin layer, and the metal layer which were cut | disconnected beforehand between a pair of press plates is arrange | positioned, and after pressing, a laminated body is taken out from a container. Thus, a laminated body may be formed by a single wafer type. And in the 1st heating means 60 and the 2nd heating means 90, you may heat a some laminated body simultaneously.

Next, examples of the present invention will be described.
Example 1
1. Adjustment of varnish of resin layer 15% by weight of novolac-type cyanate resin (Lonza Japan, Primaset PT-30, weight average molecular weight of about 2,600) as thermosetting resin, biphenyldimethylene type epoxy resin as epoxy resin (Nippon Kayaku Co., Ltd., NC-3000, epoxy equivalent 275) 12.7% by weight, phenol resin biphenyldimethylene type phenol resin (Nippon Kayaku Co., Ltd., GPH-65, hydroxyl equivalent 200) 2.3% by weight Was dissolved in methyl ethyl ketone. Further, 69.7% by weight of spherical fused silica (manufactured by Admatechs, SO-25H, average particle size 0.5 μm) as an inorganic filler and epoxysilane type coupling agent (manufactured by Nihon Unicar Co., Ltd., A-187) 0. 3 wt% was added, and the mixture was stirred for 60 minutes using a high-speed stirrer to prepare a resin layer varnish having a solid content of 70 wt%.

2. Production of carrier material On a copper foil (F2WS-12, manufactured by Furukawa Electric Co., Ltd.) having a thickness of 12 μm and a width of 480 mm, the above-mentioned varnish is applied with a comma coater device and dried with a drying device at 170 ° C. for 3 minutes. It formed so that it might become 29-33 micrometers (the 1st resin layer 3 was formed). A resin layer having a width of 410 mm was set to be the center of a copper foil having a width of 480 mm. Furthermore, a polyethylene terephthalate film (manufactured by Panac, TP-01, thickness 38 μm, width 480 mm) serving as the support base 51 was provided on the resin layer 3 to obtain a first sheet 5a.
In addition, the amount of varnish to be applied is adjusted in the same manner, and the resin layer having a thickness of 29 to 33 μm and a width of 410 mm is the center in the width direction of a copper foil having a width of 480 mm (F2WS-12, manufactured by Furukawa Electric Co., Ltd.). (The second resin layer 4 was formed). A support base 51 was provided on the resin layer 4 to obtain a second sheet 5b.

3. Production of Cured Body A cured body was produced using the production apparatus 30 of the above embodiment.
A T-glass woven fabric (cross type # 2116, width 360 mm, thickness 87 μm, basis weight 104 g / m ² ) was used as the fiber base material.
First, the space S was depressurized to 10 torr (1333 Pa), and the first sheet 5 a and the second sheet 5 b were supplied into the space S. As in the previous embodiment, the support base 51 of the first sheet 5a and the support base 51 of the second sheet 5b were peeled off by the rollers 73a and 73b.
And the metal layer 12, the 1st resin layer 3, the fiber base material 2, the 2nd resin layer 4, and the 2nd resin layer 4 provided in the 1st resin layer 3 with 70 degreeC roller 72a, 72b. The metal layer 12 provided on the substrate was pressed.
Thereafter, the laminated sheet 40 </ b> A was heated by the first heating means 60. At this time, the temperature of the heating roller was 100 ° C., and the tension applied to the laminated sheet 40A was 300N.
Thereafter, the laminated sheet 40A was heated by the second heating means 90. The temperature of the heater of the second heating means 90 was 150 ° C., and the tension applied to the laminated sheet 40A when the laminated sheet 40A passed through the vertical heating furnace 91 was 50N.
Furthermore, the time taken for the laminated sheet 40A to pass through the second heating means 90 was 2 minutes.
As described above, the thickness is 102 μm (the thickness of the non-impregnated portion of the first resin layer: 7.5 μm, the fiber base material: 87 μm, the thickness of the non-impregnated portion of the second resin layer: 7.5 μm). A laminated sheet 40A was obtained. The curing rate of the resin layers 3 and 4 of the laminated sheet 40A was 5% to 30%, which was a B stage.
Next, the laminated sheet 40A is cut, the end of the laminated sheet 40A cut by the jig 87 of the curing device 30C is gripped, the plurality of laminated sheets 40A are suspended in the heating furnace 85, and the laminated sheet 40A Heat curing was performed. The heating time was 2 hours, and the heating temperature was 225 ° C. (below the glass transition point of the cured product described later). At this time, the laminated sheet 40A was heat-cured without applying pressure to the laminated sheet 40A.
The curing rate of the resin layers 3 and 4 of the cured body (laminated sheet 40B) obtained as described above was 90% or more, and was a C stage. That is, the adhesive strength between the resin layers 3 and 4 and the metal layer 12 in the laminated sheet 40B was higher than the adhesive strength between the resin layers 3 and 4 and the metal layer 12 in the laminated sheet 40A.

(Comparative Example 1)
The cut laminated sheet 40A was heated under pressure with a pair of press plates, and the laminated sheet 40A was heated and cured. The applied pressure was 0.2 to 4.0 MPa, the heating time was 2 hours, and the heating temperature was 225 ° C. Other points are the same as those of the first embodiment.

The dimensional change of the cured body obtained in Example 1 (laminated sheet 40B) and the cured body obtained in Comparative Example 1 was measured at room temperature in accordance with 2.4.39 of IPC-TM-650. The initial dimension of the obtained cured product is A, and after removing the metal foils on both sides by etching, a preheating treatment at 105 ° C. for 4 hours, and a reflow treatment at a surface temperature of 260 to 265 ° C. for 30 seconds, When the dimension after performing the heat treatment consisting of is B, the dimensional change rate is expressed by the following equation.
Dimensional change rate (%) = (B−A) / A × 100
Here, the vertical direction refers to the transport direction of the cured body (so-called MD), and the horizontal direction refers to the direction orthogonal to the transport direction of the cured body (so-called TD). The temperature of the preheating treatment is the ambient temperature, and the temperature of the reflow treatment is the temperature of the surface of the cured body.
The results are shown in FIGS. 11 and 12, reflow × 1 means that the above-described reflow processing is performed once, and reflow × 3 means that the above-described reflow processing is performed three times. Moreover, the vertical axis | shaft of FIG.
Compared to Example 1, the dimensional change rate of the cured body before and after reflow in Comparative Example 1 was large.

2 Fiber base material 3 1st resin layer 4 2nd resin layer 5a 1st sheet 5b 2nd sheet 12 Metal layer 30 Laminated sheet manufacturing apparatus 30A Manufacturing apparatus 30B Cutting apparatus 30C Curing apparatus 31 Impregnation part 32 Non-impregnation part 40A Laminated sheet 40B Laminated sheet 41 Impregnated portion 42 Non-impregnated portion 51 Support base 60 First heating means 61a Heating roller 61b Heating roller 70 Laminating means 71a First roller 71b First roller 72a Second roller 72b Second roller 73a Third Roller 73b Third roller 75 Housing 76 Depressurizing means 77 Sealing material 81 Flattening means 82 Cutting means 85 Heating furnace 86 Heater 87 Jig 88 Support material 90 Second heating means 91 Vertical heating furnace 92 Pressure roller 711 Main body Portion 711A Outer peripheral surface 712 Shaft 751 Wall 751A Recess 751B Opening 761 Pump 762 Connection 771 bearings 811 roller F1 pressing force F2 vacuum force G air S space D table B1 belt conveyor

Claims (9)

Preparing a laminate comprising a prepreg impregnated with a thermosetting resin material in a fiber base and a sheet temporarily bonded to at least one of the front and back surfaces of the prepreg;
A method for producing a cured body, including a step of heating the thermosetting resin material without applying pressure to the laminated body so that the thermosetting resin material is cured, and finally bonding the sheet and the prepreg. In the manufacturing method of the hardening body of Claim 1,
The said hardening body is a manufacturing method of the hardening body for printed wiring boards. In the manufacturing method of the hardening body of Claim 1 or 2,
The fiber which comprises the said fiber base material is a manufacturing method of the hardening body comprised by any material of glass, polyparaphenylene benzobisoxazole, an aramid resin, and polyester. In the manufacturing method of the hardening body in any one of Claims 1 thru | or 3,
In the step of preparing the laminate, the resin material of the prepreg is in a B stage state,
The manufacturing method of the hardening body which hardens | cures the resin material of the said prepreg to a C stage by the said heating in the said process to perform this adhesion | attachment. In the manufacturing method of the hardening body in any one of Claims 1 thru | or 4,
In the step of preparing the laminate,
The long fiber substrate is impregnated with the resin material to obtain the long prepreg, and the resin material is heated to cure, so that at least one of the front and back surfaces of the prepreg A long sheet is temporarily bonded to the surface, and the long laminate having the long prepreg and the long sheet is prepared,
This laminate is cut into predetermined dimensions,
In the step of performing the main bonding, a method of manufacturing a cured body that heats the cut laminated body in a state where the laminated body is suspended from a jig without applying pressure. In the manufacturing method of the hardening body in any one of Claims 1 thru | or 4,
The long fiber substrate is impregnated with the resin material to obtain the long prepreg, and the resin material is heated to cure, so that at least one of the front and back surfaces of the prepreg A long sheet is temporarily bonded to the surface, and the long laminate having the long prepreg and the long sheet is prepared,
This laminate is cut into predetermined dimensions,
In the step of performing the main bonding, the cured product is mounted on a conveyor that moves in the horizontal direction, and heated without being pressurized while the laminate is transported by the conveyor. In the manufacturing method of the hardening body in any one of Claims 1 thru | or 6,
The manufacturing method of the hardening body which heats the said laminated body at the temperature below the glass transition point of the said resin material in the said hardening body in the said process to carry out this adhesion | attachment. In the manufacturing method of the hardening body in any one of Claims 1 thru | or 7,
The said sheet | seat is a manufacturing method of the hardening body which is a metal foil or a resin substrate with a metal foil. In the manufacturing method of the hardening body in any one of Claims 1 thru | or 8,
In the step of preparing the laminate,
The resin layer of a sheet material having a resin layer composed of the resin material and the sheet provided on the resin layer is brought into contact with at least one surface of the fiber base, and the resin layer is The manufacturing method of the hardening body which impregnates a fiber base material and comprises the said laminated body.

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