Manufacturing method of FRP precursor, FRP precursor, laminate, multilayer printed wiring board and semiconductor package

Abstract

To provide a production method for an FRP precursor having excellent productivity, an FRP precursor produced by the production method, and a laminated board, a multilayer printed wiring board, and a semiconductor package using the FRP precursor.SOLUTION: A production method for an FRP precursor in which a sheet-like aggregate is impregnated with a thermosetting resin film by pressure welding includes a step of performing pressure welding impregnation of the thermosetting resin film from only one surface of the sheet-like aggregate. The FRP precursor is produced by the production method. The FRP precursor is used for a laminated board, a multilayer printed wiring board, and a semiconductor package.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a method for producing an FRP precursor, and a method for producing an FRP precursor, a laminate, a multilayer printed wiring board, and a semiconductor package. [Background technology]

[0002] FRP (Fiber Reinforced Plastics) is a composite material in which a fibrous material with a high elastic modulus, such as fiber, is used as an aggregate and this aggregate is placed in a base material (matrix), such as plastic, to improve strength. Taking advantage of its weather resistance, heat resistance, chemical resistance, and light weight, FRP is an inexpensive, lightweight, and highly durable material. Taking advantage of these properties, FRP is used in a wide range of fields. For example, because of its moldability and high strength, FRP is used as a structural material for housing equipment, ships, vehicles, aircraft, etc. Also, taking advantage of its insulating properties, FRP is used in the field of electronic parts such as electrical equipment and printed wiring boards.

[0003] When using FRP for printed wiring boards, the thickness of the FRP must be thinner than that of FRP for other uses.Furthermore, FRP for printed wiring boards must have high specifications, such as a narrow range of thickness variation after molding and no voids. For this reason, most FRP for printed wiring boards is manufactured by the hand lay-up (HLU) method, which involves using a coating machine or the like to apply a varnish made by dissolving resin in a solvent to aggregate, and then heating and drying the varnish to remove the solvent and thermally harden the resin (see, for example, Patent Document 1).

[0004] However, when non-calendared aramid nonwoven fabric, thin glass paper, thin woven fabric, or the like is used as an aggregate, the strength of these aggregates is low, so they may tear when the coater gap is narrowed to adjust the amount of resin to be applied, or they may break when drying, heat curing, or the like after application because their own weight exceeds the load capacity of the aggregate, resulting in poor workability. In addition, FRP for printed wiring boards must be able to achieve both high accuracy of thickness after lamination and the ability to fill the inner layer circuit pattern with resin (moldability). This is complicated, as it is necessary to manufacture multiple types of FRP precursors from one type of aggregate, such as those with a few mass percent difference in the amount of resin attached to the aggregate, those with different curing times for the thermosetting resin, and combinations of these. Furthermore, since each type is manufactured under different coating conditions, there is a large loss of materials used in the manufacturing process.

[0005] Therefore, a method for producing an FRP precursor has been investigated in which, rather than directly applying a thermosetting resin to aggregate, a resin film is first prepared by distributing the thermosetting resin in a film form, and then the sheet-like aggregate and the resin film are heated and pressurized to pressure-bond and impregnate them (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 01-272416 [Patent Document 2] JP 2011-132535 ​​A Summary of the Invention [Problem to be solved by the invention]

[0007] In the method of press-contacting and impregnating a resin film into an aggregate, a method in which a pair of resin films is press-contacted and impregnated from both sides of a sheet-like aggregate (hereinafter also referred to as a "double-sided press-contact impregnation method") is the mainstream. However, with the double-sided pressure-welding impregnation method, two resin films are required, each made with half the amount of resin required for the final product, to be pressure-welded to both sides. In other words, it is necessary to prepare a resin film twice as long as the FRP precursor to be produced, which is poor in productivity and yield. In addition, when producing a resin film with a small amount of resin, the heat during drying is easily transferred to the resin and hardening progresses, so the drying conditions of the applied varnish must be strictly controlled, making the work complicated.

[0008] The resin film is usually produced by applying a varnish in which a thermosetting resin is dissolved in an organic solvent to a support and then drying. At this time, in order to improve the productivity of the FRP precursor, it is desirable to dry at a temperature higher than the boiling point of the solvent and perform the drying in a short time. On the other hand, from the viewpoint of impregnation into the aggregate, it is desirable to dry the varnish at a low temperature and moderately suppress the progress of hardening of the resin film to maintain a low minimum melt viscosity. That is, in order to improve the productivity of the FRP precursor, it is necessary to simultaneously keep the minimum melt viscosity of the obtained resin film low and quickly remove the solvent during drying, but the heating conditions required to achieve these are contradictory, making it difficult to achieve them.

[0009] The present invention has been made in consideration of the above problems, and has an object to provide a method for producing an FRP precursor with excellent productivity, an FRP precursor produced by the production method, and a laminate board, a multilayer printed wiring board, and a semiconductor package each using the FRP precursor. [Means for solving the problem]

[0010] As a result of intensive research into solving the above problems, the present inventors have found that the above problems can be solved by the present invention described below, and have completed the present invention. That is, the present invention relates to the following [1] to

[12] . [1] A method for producing an FRP precursor by heating and pressure-impregnating a thermosetting resin film onto a sheet-like aggregate, the method including a step of pressure-impregnating the thermosetting resin film from only one side of the sheet-like aggregate. [2] The method for producing an FRP precursor according to the above [1], wherein the pressure-contact impregnation of the thermosetting resin film is carried out by lamination. [3] The method for producing an FRP precursor according to the above [1] or [2], wherein the minimum melt viscosity of the thermosetting resin film is 500 to 1,000 mPa·s. [4] The air permeability of the aggregate is 110cc / cm 2 / sec or more. [5] The method for producing an FRP precursor according to any one of the above [1] to [4], wherein the thermosetting resin film is pressed into and impregnated into the sheet-shaped aggregate at a linear pressure of 0.1 to 1 MPa. [6] The method for producing an FRP precursor according to any one of the above [1] to [5], wherein the ratio of a thickness of the thermosetting resin film to a thickness of the sheet-like aggregate [thermosetting resin film / sheet-like aggregate] is 1.1 to 2.5. [7] The thermosetting resin film is a first support-attached thermosetting resin film having a first support on one surface thereof, The first support-attached thermosetting resin film is placed on one surface of the sheet-like aggregate so that the thermosetting resin film is on the one surface side of the sheet-like aggregate; A second support is placed on the other surface of the sheet-like aggregate, The method for producing an FRP precursor according to any one of the above [1] to [6], further comprising pressure-impregnating the thermosetting resin film. [8] The method for producing an FRP precursor according to the above [7], wherein the material of the first support body and the material of the second support body are the same. [9] An FRP precursor produced by the method for producing an FRP precursor according to any one of [1] to [8] above.

[10] A laminate obtained by laminating and molding the FRP precursor described in [9] above.

[11] A multilayer printed wiring board produced using the laminate described in

[10] above.

[12] A semiconductor package comprising the multilayer printed wiring board according to

[11] above and a semiconductor mounted thereon. Effect of the Invention

[0011] According to the present invention, it is possible to provide a method for producing an FRP precursor with excellent productivity, an FRP precursor produced by the method, and a laminate board, a multilayer printed wiring board, and a semiconductor package each using the FRP precursor. [Brief description of the drawings]

[0012] [Figure 1]1 is a conceptual diagram of a method and an apparatus for producing an FRP precursor according to the present invention. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] [Manufacturing method of FRP precursor] The method for producing an FRP precursor of the present embodiment is a method for producing an FRP precursor in which a thermosetting resin film is pressure-impregnated into a sheet-shaped aggregate, and the pressure-impregnation of the thermosetting resin film is performed from only one side of the sheet-shaped aggregate. Hereinafter, the sheet-shaped aggregate may be simply referred to as “aggregate,” and the thermosetting resin film may be simply referred to as “resin film.” The “resin film” does not include a protective film and a support, which will be described later. Furthermore, a method in which the pressure-contact impregnation of the thermosetting resin film is carried out from only one side of the sheet-like aggregate is sometimes called a "single-side pressure-contact impregnation method." In the present invention, the term "pressure contact" means applying pressure in a contact state.

[0014] In the method for producing an FRP precursor of the present embodiment, the thermosetting resin film is a first support-attached thermosetting resin film having a first support on one surface thereof, The first support-attached thermosetting resin film is placed on one surface of the sheet-like aggregate so that the thermosetting resin film is on the one surface side of the sheet-like aggregate; A second support is placed on the other surface of the sheet-like aggregate, It is preferable that the thermosetting resin film is impregnated by pressure welding. Hereinafter, the method for producing the FRP precursor of this embodiment will be described with reference to FIG.

[0015] The FRP precursor manufacturing apparatus 1 presses and impregnates the resin film 54 from one surface of the aggregate 40, and presses and contacts the second support 56 from the other surface of the aggregate 40. The second support 56 is used for the purposes of preventing resin from seeping out from the side of the aggregate 40 on which the resin film 54 is not placed when the resin film 54 is pressed and impregnated, and for the purposes of stabilizing the surface condition of the resulting FRP precursor. The FRP precursor manufacturing apparatus 1 is placed under normal pressure. The FRP precursor manufacturing method of this embodiment can be performed in the FRP precursor manufacturing apparatus 1.

[0016] The FRP precursor manufacturing apparatus 1 includes an aggregate delivery device 2, a resin film delivery device 3, a second support delivery device 3', a sheet heating and pressurizing device 6, a sheet pressurizing and cooling device 7, and an FRP precursor winding device 8. The FRP precursor manufacturing apparatus 1 preferably further includes a protective film peeling mechanism 4 and a protective film winding device 5. The FRP precursor manufacturing apparatus 1 may also include an aggregate heating device (not shown) for heating the aggregate before being sent to the sheet heating and pressurizing device 6, and a resin film heating device (not shown) for heating the resin film before being sent to the sheet heating and pressurizing device 6.

[0017] The aggregate delivery device 2 is a device that rotates the roll on which the sheet-shaped aggregate 40 is wound in the direction opposite to the winding direction, and delivers the aggregate 40 wound on the roll. In Fig. 1, the aggregate delivery device 2 delivers the aggregate 40 from the lower side of the roller toward the sheet heating and pressing device 6.

[0018] The resin film delivery device 3 has a roll on which a first support and a resin film 50 with a protective film (hereinafter also simply referred to as "multilayer film 50") are wound, and a support mechanism that rotatably supports the roll while applying a predetermined tension to the delivered multilayer film 50, and is a device that rotates the roll on which the multilayer film 50 is wound in the direction opposite to the winding direction to deliver the multilayer film 50 wound on the roll. The multilayer film 50 is a sheet-like multilayer film including a resin film 54, and of both surfaces of the resin film 54, a protective film 52 laminated on a surface 54a on the aggregate 40 side, and a first support 53 laminated on a surface 54b opposite the aggregate 40. The resin film feeding device 3 is positioned on the surface 40a side of the fed aggregate 40, and feeds the multilayer film 50 from the underside of the roller toward one of the protective film peeling mechanisms 4 so that the protective film 52 is on the side of the fed aggregate 40.

[0019] The second support feeding device 3' has a roll on which the second support 56 is wound, and a support mechanism that rotatably supports the roll while applying a predetermined tension to the second support 56 being fed out, and is a device that rotates the roll on which the second support 56 is wound in the direction opposite to the winding direction, thereby feeding out the second support 56 wound on the roll. The second support body delivery device 3 ′ is a device located on the back surface 40 b side of the delivered aggregate 40 , and delivers the second support body 56 from above the roller toward the sheet heating and pressurizing device 6 .

[0020] The protective film peeling mechanism 4 is a deflecting roller located on the side of the surface 40a of the delivered aggregate 40. The protective film peeling mechanism 4 receives the multilayer film 50, which is delivered from the resin film delivery device 3 and advances toward the protective film peeling mechanism 4, on the surface of the rotating deflecting roller. Furthermore, the protective film 52 is peeled off from the multilayer film 50 by advancing the first supported resin film 55 of the multilayer film 50 toward the sheet heating and pressurizing device 6 and advancing the protective film 52 toward the protective film winding device 5. As a result, the aggregate-side film surface 54a of the resin film 54 is exposed.

[0021] The protective film winding device 5 is located on the surface 40 a side of the delivered aggregate 40 , and is a winding device that winds up the protective film 52 peeled off by the protective film peeling mechanism 4 .

[0022] The sheet heating and pressurizing device 6 has a pair of heating and compression rollers and a compression force applying mechanism (not shown) that applies a compression force to the pair of heating and compression rollers. The pair of heating and compression rollers has a heater inside so that heating can be performed at a predetermined set temperature. The sheet heating and pressurizing device 6 presses and impregnates the aggregate 40 with the resin film 54 using a pair of rotating heating and compression rollers to form a sheet-like FRP precursor 60 (film pressing process), and sends the FRP precursor 60 toward the sheet pressing and cooling device 7. At this time, the first support-attached resin film 55 is laminated onto the aggregate 40 so that the aggregate-side film surface 54a of the resin film 54 is adhered to the surface 40a of the aggregate 40, and the second support 56 is laminated onto the aggregate 40 so that it is adhered to the back surface 40b of the aggregate 40, thereby forming the FRP precursor 60. The temperature of the heat-pressure roller is preferably within a range of the minimum melt viscosity temperature of the resin film used +2 to 30° C., more preferably +4 to 20° C. The method for measuring the minimum melt viscosity temperature of the resin film is as described below. The line pressure when the resin film is pressed into and impregnated into the sheet-like aggregate is preferably 0.1 to 1 MPa, more preferably 0.2 to 0.7 MPa, and even more preferably 0.3 to 0.5 MPa. The FRP precursor 60 delivered from the sheet heating and pressing device 6 is in a high temperature state.

[0023] The sheet pressurizing and cooling device 7 has a pair of cooling and compression rollers and a compression force applying mechanism (not shown) that applies a compression force to the pair of cooling and compression rollers. The pair of cooling and compression rollers compress and cool the high-temperature FRP precursor 60 sent out from the sheet heating and pressing device 6 with the pair of rotating cooling and compression rollers, and send it to the FRP precursor winding device 8.

[0024] The FRP precursor winding device 8 has a roll that winds up the sheet-like FRP precursor 60 sent out from the sheet pressurizing and cooling device 7, and a drive mechanism (not shown) that rotates the roll.

[0025] The above-described FRP precursor manufacturing apparatus 1 operates as follows.

[0026] First, the sheet-shaped aggregate 40 is delivered from the aggregate delivery device 2 toward the sheet heating and pressurizing device 6. At this time, the front surface 40a and the back surface 40b of the aggregate 40 are exposed. The front surface 40a and the back surface 40b of the delivered aggregate 40 may each be heated by an aggregate heating device (not shown) under normal pressure.

[0027] On the other hand, the resin film feeding device 3 feeds the first support body and the resin film 50 with protective film (multilayer film 50) from the underside of the roller toward the protective film peeling mechanism 4 so that the protective film 52 is on the side of the aggregate 40 that has been fed out. Further, the second support body delivery device 3 ′ delivers the second support body 56 from above the roller toward the sheet heating and pressing device 6 .

[0028] The sent-out multilayer film 50 is hung on a turning roller, which is the protective film peeling mechanism 4, and when turned, the protective film 52 is peeled off so that the aggregate-side film surface 54a is exposed. The peeled-off protective film 52 is taken up by the protective film take-up device 5. The first supported resin film 55 from which the protective film 52 has been peeled off is sent out toward the sheet heating and pressurizing device 6.

[0029] The aggregate 40 delivered from the aggregate delivery device 2, the first supported resin film 55 delivered from the protective film peeling mechanism 4, and the second support 56 are inserted between a pair of heating and compression rollers provided in the sheet heating and pressurizing device 6. At this time, of the first supported resin film 55, the aggregate-side film surface 54a of the resin film 54 is laminated on the surface 40a of the aggregate 40, and the second support 56 is laminated on the back surface 40b of the aggregate 40. Then, under normal pressure, the resin film 54 is pressed and impregnated into the aggregate 40 by the sheet heating and pressing device 6 to obtain the FRP precursor 60. At this time, the pair of heating and pressing rollers are maintained at a predetermined temperature by controlling the temperature of the heater inside the pair of heating and pressing rollers, and pressure is applied while being heated during the film pressing process. According to the above embodiment, the first support 53, the FRP precursor 60, and the second support 56 are laminated in this order to obtain the FRP precursor 60 having supports on both sides.

[0030] The FRP precursor 60 sent out from the sheet heating and pressurizing device 6 is further pressurized and cooled by the sheet pressurizing and cooling device 7 . The FRP precursor 60 sent out from the sheet pressurizing and cooling device 7 is wound up by an FRP precursor winding device 8.

[0031] In the above example, one resin film is laminated to the aggregate, but two or more resin films may be laminated to the aggregate. In this case, the two or more resin films may be combined to have different thermosetting degrees, compounding compositions, etc.

[0032] The obtained FRP precursor may be cut to a desired size, adhered to a desired object, and heat cured. The FRP precursor may also be used in a roll-to-roll process.

[0033] The FRP precursor produced by the FRP precursor production apparatus 1 will be described.

[0034] <Sheet-shaped aggregate> The aggregate used in the manufacturing method of this embodiment can be any well-known material used in various laminates for electrical insulating materials. The aggregate is preferably a fiber substrate, and examples of the material of the fiber substrate include natural fibers such as paper and cotton linters; inorganic fibers such as glass fibers and asbestos; organic fibers such as aramid, polyimide, polyvinyl alcohol, polyester, tetrafluoroethylene, and acrylic; and mixtures thereof. Among these, glass cloth is preferred from the viewpoint of flame retardancy. Examples of glass cloth include glass cloth using E glass, C glass, D glass, S glass, etc., or glass cloth in which short fibers are bonded with an organic binder; and a mixture of glass fiber and cellulose fiber. These fiber substrates have shapes such as woven fabric, nonwoven fabric, roving, chopped strand mat, surfacing mat, etc. The material and shape of the aggregate are selected depending on the intended use and performance of the molded product, and one type may be used alone, or two or more types of materials and shapes may be combined as necessary.

[0035] The thickness of the sheet-like aggregate is preferably 3 to 50 μm, more preferably 5 to 20 μm, and even more preferably 7 to 15 μm, from the viewpoint of thinning the printed wiring board and the strength of the resulting FRP precursor.

[0036] Air permeability of sheet aggregate (cc / cm 2 / sec) is 110cc / cm from the viewpoint of the impregnation of the resin film. 2 / sec or more is preferable, and 200cc / cm 2 / sec or more is preferable, and 260cc / cm 2 From the viewpoint of the strength of the resulting FRP precursor, it is more preferable that the flow rate is 500 cc / cm 2 / sec or less. The air permeability of the sheet aggregate is measured using a 300 mm x 1260 mm sheet aggregate sample with a Frazier type air permeability tester manufactured by Toyo Seiki Seisakusho Co., Ltd.

[0037] <Thermosetting resin film> The thermosetting resin film used in the manufacturing method of the FRP precursor of this embodiment is a film containing a thermosetting resin, and is a film made of a thermosetting resin or a composition containing a thermosetting resin (hereinafter also referred to as a "thermosetting resin composition").

[0038] Examples of the thermosetting resin include epoxy resin, phenol resin, urea resin, furan resin, etc. Among these, epoxy resin is preferred from the viewpoints of workability, handling, and cost. The thermosetting resin may be used alone or in combination of two or more kinds. The epoxy resin is preferably a bifunctional or higher epoxy resin. Examples of the bifunctional or higher epoxy resin include bisphenol type epoxy resins such as bisphenol A type epoxy resins, bisphenol F type epoxy resins, and bisphenol AD ​​type epoxy resins; alicyclic epoxy resins; novolac type epoxy resins such as phenol novolac type epoxy resins, cresol novolac type epoxy resins, bisphenol A novolac type epoxy resins, and aralkyl novolac type epoxy resins; diglycidyl ethers of polyfunctional phenols; and hydrogenated products thereof.

[0039] When an epoxy resin is used as the thermosetting resin, an epoxy resin curing agent may be used. The epoxy resin curing agent may be used alone or in combination of two or more kinds. Examples of epoxy resin curing agents include phenolic resins, amine compounds, acid anhydrides, boron trifluoride monoethylamine, isocyanates, dicyandiamide, urea resins, and the like. Among these, phenolic resins are preferred. Examples of the phenol resin include novolac-type phenol resins such as phenol novolac resin and cresol novolac resin; naphthalene-type phenol resin, high-ortho-type novolac phenol resin, terpene-modified phenol resin, terpene phenol-modified phenol resin, aralkyl-type phenol resin, dicyclopentadiene-type phenol resin, salicylaldehyde-type phenol resin, and benzaldehyde-type phenol resin. The amount of the epoxy resin curing agent is preferably an amount such that the reactive group equivalent ratio of the curing agent is 0.3 to 1.5 equivalents per epoxy equivalent of the epoxy resin of 1. When the amount of the epoxy resin curing agent is within the above range, the degree of curing is easily controlled, and the productivity is improved.

[0040] The thermosetting resin composition used for forming the resin film may further contain a curing accelerator. The curing accelerator may be used alone or in combination of two or more kinds. Examples of the curing accelerator include imidazole compounds, organic phosphorus compounds, tertiary amines, and quaternary ammonium salts. The imidazole compound may be an imidazole compound in which the secondary amino group of imidazole is masked with acrylonitrile, isocyanate, melamine, acrylate, or the like to give it latent properties. Examples of the imidazole compound used here include imidazole, 2-methylimidazole, 4-ethyl-2-methylimidazole, 2-phenylimidazole, 2-undecylimidazole, 1-benzyl-2-methylimidazole, 2-heptadecylimidazole, 4,5-diphenylimidazole, 2-methylimidazoline, 2-ethyl-4-methylimidazoline, 2-undecylimidazolin, and 2-phenyl-4-methylimidazoline. In addition, a photoinitiator that generates a radical, anion, or cation by photolysis to initiate curing may be used. The amount of the curing accelerator is preferably 0.01 to 20 parts by mass relative to 100 parts by mass of the thermosetting resin. When the amount is 0.01 part by mass or more, a sufficient curing acceleration effect is obtained, and when the amount is 20 parts by mass or less, the storage stability of the thermosetting resin composition and the physical properties of the cured product are excellent, and it is also economical.

[0041] The thermosetting resin composition may further contain a filler in order to improve impermeability and abrasion resistance and to increase the amount of the filler. The filler may be used alone or in combination of two or more kinds. Examples of fillers include oxides such as silica, aluminum oxide, zirconia, mullite, and magnesia; hydroxides such as aluminum hydroxide, magnesium hydroxide, and hydrotalcite; nitride ceramics such as aluminum nitride, silicon nitride, and boron nitride; natural minerals such as talc, montmorillonite, and saponite; metal particles, and carbon particles.

[0042] Since fillers vary widely in specific gravity compared to resins, from low to high, it is preferable to consider the amount of filler added in terms of volume percentage rather than parts by mass. The amount of the filler to be added varies greatly depending on the purpose of addition, but is preferably in the range of 0.1 to 65% by volume based on the solid volume of the thermosetting resin composition. If the amount is 0.1% by volume or more, it is effective enough when added for the purpose of coloring and opacification. If the amount is 65% by volume or less, the increase in viscosity is suppressed, and the amount can be increased without deteriorating the workability and adhesiveness. Here, the solid content in this specification refers to components in the composition other than water, volatile substances such as organic solvents described later, etc. In other words, the solid content includes liquid, starch syrup, and wax-like substances at room temperature around 25° C., and does not necessarily mean solid.

[0043] In addition to the above components, the thermosetting resin composition may contain other components as necessary within a range that does not impair the effects of the present invention. For example, a flexible material may be added to impart tackiness of the resin to the cured resin and improve adhesion during adhesion. Examples of the flexible material include polystyrene, polyolefin, polyurethane, acrylic resin, acrylonitrile rubber, polyvinyl alcohol, those modified with epoxy or carboxyl groups to incorporate them into the curing system, and phenoxy obtained by reacting epoxy resin in advance to make it into a large molecule.

[0044] In order to achieve homogenization, the thermosetting resin composition is preferably in the form of a varnish in which it is dissolved and / or dispersed in an organic solvent. The organic solvent may be used alone or in combination of two or more kinds. Examples of the organic solvent include acetone, methyl ethyl ketone, toluene, xylene, cyclohexanone, 4-methyl-2-pentanone, ethyl acetate, ethylene glycol monoethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, tripropylene glycol monomethyl ether, N,N-dimethylformamide, and N,N-dimethylacetamide.

[0045] The resin film can be produced by applying the thermosetting resin composition obtained by blending the above-mentioned components onto a support, removing unnecessary organic solvent, and thermally curing the composition. The thermosetting herein is intended to bring the thermosetting resin composition into a so-called semi-cured (B-stage) state, and it is preferable to semi-cure the thermosetting resin composition so that the viscosity thereof is such that workability in lamination is good. From the viewpoint of improving the impregnation property of the resin film, the minimum melt viscosity of the resin film is preferably from 500 to 3,000 mPa·s, more preferably from 600 to 2,000 mPa·s, and even more preferably from 700 to 1,000 mPa·s. The minimum melt viscosity temperature of the resin film is preferably from 60 to 150°C, more preferably from 80 to 130°C, and even more preferably from 100 to 120°C, from the viewpoint of productivity of the FRP precursor. The minimum melt viscosity and the minimum melt viscosity temperature can be measured by the method described in the Examples.

[0046] The thickness of the resin film is preferably from 5 to 40 μm, more preferably from 10 to 30 μm, and even more preferably from 15 to 25 μm, from the viewpoint of thinning the printed wiring board and the strength of the resulting FRP precursor.

[0047] When laminating the resin film and the aggregate, the thickness of the resin film is preferably made thicker than the thickness of the aggregate, taking into consideration the target thickness of the FRP precursor and formability during press molding. The ratio of the thickness of the resin film to the thickness of the aggregate [thermosetting resin film / sheet-shaped aggregate] is preferably 1.1 to 2.5, more preferably 1.3 to 2.2, and even more preferably 1.5 to 2.0, from the viewpoint of formability.

[0048] <Support> Examples of the support (first support) for the resin film include organic films such as polyethylene terephthalate (PET), biaxially oriented polypropylene (OPP), polyethylene, polyvinyl fluorate, and polyimide; films of copper, aluminum, and alloys of these metals; and films of these organic films or metal films whose surfaces have been subjected to a release treatment with a release agent.

[0049] The second support may be the same as the first support described above. The first support and the second support are preferably made of the same material. When the first support and the second support are made of the same material, the behavior during thermocompression bonding is uniform on the front and back of the FRP precursor, and it is possible to suppress the occurrence of appearance defects such as increased residual stress in the product and wrinkles due to differences in the thermal shrinkage and dimensional change rates of the supports, etc. during thermocompression bonding.

[0050] [Laminate] The laminate of this embodiment is a laminate obtained by laminating and molding the FRP precursor obtained by the method for producing an FRP precursor of this embodiment. The laminate of this embodiment includes a laminate containing the FRP precursor or an FRP obtained by curing the FRP precursor, as well as a metal-clad laminate having a metal foil on the laminate. The FRP obtained by curing an FRP precursor is an FRP obtained by C-staging (curing) an FRP precursor in a B-stage (semi-cured) state, and the present invention also provides this FRP.

[0051] Specifically, the laminate of this embodiment can be manufactured by stacking one or more (preferably 2 to 20) FRP precursors under predetermined conditions. A substrate with inner layer circuit processing may be sandwiched between the FRP precursors. The FRP precursors are hardened (C-staged) by the stacking to become FRP. Furthermore, a metal-clad laminate can be produced by stacking one or more (preferably 2 to 20) sheets of the FRP precursor and arranging a metal foil on one or both sides, preferably both sides, of the stack.

[0052] The lamination conditions may be known conditions used in the manufacture of laminates for use in printed wiring boards, such as a multi-stage press, a multi-stage vacuum press, a continuous molding machine, an autoclave molding machine, etc., at a temperature of 100 to 250°C, a pressure of 0.2 to 10 MPa, and a heating time of 0.1 to 5 hours.

[0053] The thickness of the metal foil is preferably 40 μm or less, more preferably 1 to 40 μm, even more preferably 5 to 40 μm, even more preferably 5 to 35 μm, particularly preferably 5 to 25 μm, and most preferably 5 to 17 μm.

[0054] From the viewpoint of electrical conductivity, the metal of the metal foil is preferably copper, gold, silver, nickel, platinum, molybdenum, ruthenium, aluminum, tungsten, iron, titanium, chromium, or an alloy containing at least one of these metal elements. As the alloy, a copper-based alloy, an aluminum-based alloy, or an iron-based alloy is preferable. As the copper-based alloy, a copper-nickel alloy or the like can be mentioned. As the iron-based alloy, an iron-nickel alloy (42 alloy) or the like can be mentioned. Among these, as the metal, copper, nickel, and 42 alloy are more preferable, and from the viewpoint of availability and cost, copper is further preferable.

[0055] [Printed wiring board] The printed wiring board of this embodiment is a printed wiring board manufactured using the laminate of this embodiment. The printed wiring board of the present embodiment can be manufactured, for example, by forming a wiring pattern on the laminate of the present embodiment. Examples of the method for forming the wiring pattern include known methods such as a subtractive method, a full additive method, a semi-additive method (SAP: Semi Additive Process), and a modified semi-additive method (m-SAP: modified Semi Additive Process).

[0056] [Semiconductor package] The semiconductor package of this embodiment is a semiconductor package in which a semiconductor is mounted on the printed wiring board of this embodiment. The semiconductor package of this embodiment can be manufactured by mounting semiconductor elements such as a semiconductor chip and a memory at predetermined positions on the printed wiring board of this embodiment and sealing the semiconductor elements with a sealing resin or the like. EXAMPLES

[0057] The present invention will now be described in more detail with reference to the following examples, which should not be construed as limiting the invention. The performance of the thermosetting resin and FRP precursor produced in each example was measured by the following methods.

[0058] [Minimum melt viscosity of resin film] The resin film obtained in each example was used as a measurement sample, and the minimum melt viscosity and minimum melt viscosity temperature were measured under the following conditions. Measurement equipment: AR2000ex (TA Instruments) Measurement temperature range: 50~200℃ Heating rate: 3℃ / min Test piece: 20mm round tablet compressed from resin-coated film Load: 0.20N

[0059] [Impregnation of aggregate with thermosetting resin] The surface of the FRP precursor obtained in each example was observed at 100x magnification using an optical microscope, and the impregnation ability was evaluated based on the following criteria. (Evaluation Criteria) A: There are no parts of the aggregate that have not been impregnated with resin. B: There is a very small amount of resin-unimpregnated part in the aggregate. C: There is a small amount of resin-unsaturated part in the aggregate. D: There are many parts of the aggregate that are not impregnated with resin, or the aggregate is not impregnated with resin, or the aggregate is exposed.

[0060] [Appearance of FRP precursor] The surface of the FRP precursor obtained in each example was observed at 100x magnification using an optical microscope, and the appearance was evaluated based on the following criteria. (Evaluation Criteria) A: No abnormalities in appearance. B: Slight abnormality in appearance. C: Many external abnormalities.

[0061] [Preparation of thermosetting resin varnish] Preparation Example 1 To 100 parts by mass of phenol novolac epoxy resin (N-660; manufactured by DIC Corporation) and 60 parts by mass of cresol novolac resin (KA-1165; manufactured by DIC Corporation), 15 parts by mass of cyclohexane and 130 parts by mass of methyl ethyl ketone were added and dissolved by stirring. To this, 180 parts by mass of aluminum hydroxide (CL-303; manufactured by Sumitomo Chemical Co., Ltd.) as an inorganic filler, 1 part by mass of a coupling agent (A-187; manufactured by Momentive Performance Materials Co., Ltd.), and 2.5 parts by mass of isocyanate mask imidazole (G8009L; manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) as a curing accelerator were added, and the mixture was stirred to dissolve and disperse, to obtain a thermosetting resin varnish with a solid content concentration of 70% by mass.

[0062] [Manufacture of FRP precursor 1] Examples 1 to 9 (1) Preparation of resin films A to C The thermosetting resin varnish obtained above was applied to a 580 mm wide PET film (G-2; manufactured by Teijin DuPont Films Co., Ltd.) as a support with a coating width of 540 mm so that the resin film would have a thickness of 20 μm after drying, and then dried under specified conditions to produce resin films A to C with a support. Drying was performed until the amount of residual solvent in the resin film was 1.0 mass% or less, and the drying conditions were adjusted so that the minimum melt viscosity of resin film A was 1,500 mPa s, the minimum melt viscosity of resin film B was 700 mPa s, and the minimum melt viscosity of resin film C was 2,500 mPa s.

[0063] (2) Pressurizing and impregnating the aggregate Next, the resin film obtained above was wrapped around a glass cloth (breathability: as shown in Table 1, basis weight: 10.2 g / m) in the combination shown in Table 1. 2The glass cloth was sandwiched between heated and pressurized rolls with the same support as the above-mentioned support applied to only one side of the glass cloth (IPC#1010, width 550 mm, thickness 11 μm, manufactured by Unitika Ltd.) and the other side of the glass cloth was covered with the same support as the above-mentioned support, and the glass cloth was pressurized and impregnated with the resin film under the lamination conditions shown in Table 1. The glass cloth was then cooled with a cooling roll and taken up to obtain an FRP precursor. The lamination was performed roll to roll, and the line speed was constant at 1.0 m / min.

[0064] The evaluation results of the FRP precursors obtained in each example are shown in Table 1.

[0065] [Table 1]

[0066] From Examples 1 to 3 in Table 1, it can be seen that Examples 1 and 2, which used resin films with a minimum melt viscosity of 1,500 mPa·s or 750 mPa·s, have better impregnation into aggregate than Example 3, which used a resin film with a minimum melt viscosity of 2,500 mPa·s. Furthermore, from Examples 4 to 7 in Table 1, it can be seen that Examples 5 to 7, in which the pressure during pressing was 0.3 to 0.7 MPa, are superior in impregnation into aggregate than Example 4, in which the pressure during pressing was 0.15 MPa, and among these, Example 5, in which the pressure during pressing was 0.3 MPa, and Example 6, in which the pressure during pressing was 0.5 MPa, are superior in terms of the appearance of the FRP precursor. Furthermore, from Examples 1, 8 and 9 in Table 1, the air permeability of the aggregate is 110 cc / cm 2 / sec. 2 / sec, and further 260 cc / cm 2 It can be seen that Example 1, which has a viscosity of 100 / sec, is superior in impregnation into aggregate.

[0067] Next, the productivity of the FRP precursor according to the manufacturing method of this embodiment was evaluated.

[0068] [Manufacture of FRP precursor 2] Examples 10 to 13 (1) Preparation of resin films D to G The thermosetting resin varnish prepared in Preparation Example 1 was applied to a 580 mm wide PET film (G-2; manufactured by Teijin DuPont Films Co., Ltd.) with a coating width of 540 mm so that the thickness of the resin film after drying would be 20 μm or 10 μm, and the film was dried under the conditions shown in Table 2 to obtain resin films D to G. (2) Pressurizing and impregnating the aggregate The resin films D to G obtained above were wrapped around a glass cloth (breathability: 260cc / cm 2 / sec, basis weight 10.2g / m 2 The glass cloth was pressed against only one side of a glass sheet (IPC#1010, width 550 mm, thickness 11 μm, manufactured by Unitika Co., Ltd.) and the other side of the glass cloth was pressed against the same support as the support described above, and the glass cloth was sandwiched between heated and pressurized rolls and laminated under conditions of a pressure of 0.4 MPa during pressing and a heating roll temperature of 140°C, thereby pressurizing and impregnating the resin film into the glass cloth. The glass cloth was then cooled with a cooling roll and wound up to obtain an FRP precursor. The lamination was performed roll to roll, and the line speed was constant at 1.0 m / min.

[0069] The evaluation results of the FRP precursors obtained in each example are shown in Table 2.

[0070] [Table 2]

[0071] In Table 2, it can be seen from Example 10 that a resin film having a thickness of 20 μm can sufficiently dry out the solvent under high temperature and short drying conditions of 150°C for 2 minutes, while keeping the minimum melt viscosity low and providing excellent impregnation into aggregate. On the other hand, from Example 11, it is seen that the minimum melt viscosity of a 10 μm-thick resin film is high and the impregnation into aggregate is relatively low under high-temperature and short-time drying conditions of 150° C. and 2 minutes. Also, from Example 13, it is seen that a 10 μm-thick resin film requires 5 minutes of drying under low-temperature conditions of 120° C. to set the amount of remaining solvent to a predetermined value, and it takes longer to produce the resin film than a 20 μm-thick resin film. From this, it can be seen that when comparing the case in which the resin film is pressure-inserted from only one side of the aggregate with the case in which the resin film is pressure-inserted from both sides of the aggregate, the case in which the resin film is pressure-inserted from only one side allows the thickness of the resin film to be made thicker, and therefore a resin film with excellent impregnation ability into the aggregate can be produced in a short period of time, resulting in superior productivity.

[0072] [Manufacture of FRP precursor 3] Example 14, Comparative Example 1 Next, the production time was compared between the case where the resin film D obtained above was used to produce an FRP precursor by pressure-bonding and impregnating the resin film from only one side of the aggregate, and the case where the resin film F obtained above was used to produce an FRP precursor by pressure-bonding and impregnating the resin film from both sides of the aggregate. The glass cloth and lamination conditions used here were the same as those in Example 1. The results are shown in Table 3.

[0073] [Table 3]

[0074] From Table 3, it can be seen that the one-sided pressure welding impregnation method of this embodiment requires less time for coating when producing the resin film than the conventional double-sided pressure welding impregnation method, and can significantly reduce the production time of the FRP precursor. [Explanation of symbols]

[0075] 1. FRP precursor manufacturing equipment 2. Aggregate delivery device 3. Resin film delivery device 3' Second support delivery device 4 Protective film removal mechanism 5 Protective film winding device 6 Sheet heating and pressing device (film pressing means) 7 Sheet pressurization cooling device 8 FRP precursor winding device 40 Aggregate 40a Surface of aggregate (one surface of aggregate, one of both surfaces of aggregate) 40b Back surface of aggregate (other surface of aggregate, other of both surfaces of aggregate) 50 First support and resin film with protective film (multilayer film) 52 Protective Film 53 First Support 54 Resin Film 54a Surface of the resin film on the aggregate side (surface of the film on the aggregate side) 55 First support-attached resin film 56 Second Support 60 FRP Precursor

Claims

1. A method for producing an FRP precursor by heating and pressure-impregnating a thermosetting resin film onto a sheet-like aggregate, the method comprising the steps of: pressure-impregnating the thermosetting resin film onto only one side of the sheet-like aggregate; The minimum melt viscosity of the thermosetting resin film is 500 to 3,000 mPa s; a ratio of a thickness of the thermosetting resin film to a thickness of the sheet-like aggregate [thermosetting resin film / sheet-like aggregate] is 1.1 to 2.

5.

2. The method for producing an FRP precursor according to claim 1 , wherein the pressure-contact impregnation of the thermosetting resin film is carried out by lamination.

3. the thermosetting resin film is a first support-attached thermosetting resin film having a first support on one surface thereof, The first support-attached thermosetting resin film is placed on one surface of the sheet-like aggregate so that the thermosetting resin film is on the one surface side of the sheet-like aggregate; A second support is placed on the other surface of the sheet-like aggregate, The method for producing an FRP precursor according to claim 1 or 2, further comprising the step of press-impregnating the thermosetting resin film.

4. The method for producing an FRP precursor according to claim 3 , wherein the first support body and the second support body are made of the same material.

5. A method for producing a laminate, comprising laminating and molding an FRP precursor produced by the method for producing an FRP precursor according to any one of claims 1 to 4.

6. A method for producing a multilayer printed wiring board, using a laminate produced by the method for producing a laminate according to claim 5.

7. A method for manufacturing a semiconductor package, comprising mounting a semiconductor on a multilayer printed wiring board manufactured by the method for manufacturing a multilayer printed wiring board according to claim 6.

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