JPH0564586B2 - - Google Patents

Description

[Detailed description of the invention]

[Technical Field] The present invention relates to a printed wiring board material for forming a printed wiring board used in the UHF or SHF band. [Background Art] There is a desire for circuit miniaturization in printed wiring boards used in the UHF or SHF band. This requires a printed wiring board material with a high dielectric constant insulating substrate. Conventionally, high dielectric constant insulating substrates have been made of inorganic materials, such as ceramics (alumina). This ceramic substrate had a high dielectric constant of about 10, whereas the dielectric constant of organic substrates made of epoxy resin, polyimide resin, etc. was low, about 5. However, compared to organic substrates, it was inferior in processability and could not be put to practical use. Therefore, it has been desired to develop a printed broken line board material that has an insulating substrate that has workability comparable to that of an organic substrate and a dielectric constant comparable to that of a ceramic substrate. [Object of the Invention] In view of the above circumstances, an object of the present invention is to provide a printed wiring board material that is excellent in processability, includes an insulating substrate with a high dielectric constant, and has sufficient practicality. [Disclosure of the Invention] In order to achieve the above object, the present invention provides an insulating substrate made of polyphenylene oxide, a crosslinkable polymer other than a polyfunctional maleimide type, and/or a crosslinkable monomer other than a polyfunctional maleimide type, and an inorganic A layer of a polyphenylene oxide-based resin composition containing a filler and a layer of a resin-impregnated base material impregnated with a resin other than the polyphenylene oxide-based resin composition, with this resin-impregnated base material being Its gist is a printed wiring board material constructed such that layers of polyphenylene oxide resin compositions are placed on the inside. Hereinafter, the present invention will be explained in detail with reference to the drawings showing one embodiment thereof. FIG. 1 shows an embodiment of the printed wiring board material according to the present invention. As shown in the figure,
This printed wiring board material includes an insulating substrate 1. A conductor layer 2 is formed on both sides of the insulating substrate 1. The insulating substrate 1 includes a layer 3 of a polyphenylene oxide resin composition containing polyphenylene oxide (also referred to as polyphenylene ether), a crosslinkable polymer and/or a crosslinkable monomer, and an inorganic filler; A layer of a resin-impregnated base material (hereinafter referred to as a "resin-impregnated base material") impregnated with a resin other than a nylene oxide (hereinafter referred to as "PPO") based resin composition, such as a thermosetting resin such as an epoxy resin or a polyimide resin. ) 4,4
It is made up of. In this printed wiring board material, for example, as shown in FIG. 2, a resin other than the PPO resin composition, in this example, epoxy Two resin-impregnated base materials 41 each impregnated with resin are arranged, and furthermore, metal foils 21 are arranged on the outside thereof, and these are overlapped, molded by heat pressing, etc., and hardened. obtained by. In other words, by pressure molding and curing, the second
The PPO resin composition sheet 31 in the figure is the first
The layer 3 of the PPO resin composition in the figure becomes the resin-impregnated base material 41 in FIG. 2, and the resin-impregnated base material 41 in FIG. 1 becomes the layer 4 of the resin-impregnated base material in FIG. Also, the second
The metal foil 21 in the figure is the conductor layer 2 in FIG.
becomes. Layer 3 of the PPO resin composition containing an inorganic filler is
In this example, it is formed from a PPO-based resin composition sheet 31, but it may be formed from a resin-impregnated base material impregnated with a PPO-based resin composition containing an inorganic filler, or a combination of these may be formed. It may be formed from. In other words, layer 3 is made of a PPO resin composition containing an inorganic filler as the sole material.
The layer 3 may be composed of the following materials, or may be composed of the layer 3 in combination with other materials. The number and arrangement order of the layers of the PPO-based resin composition containing an inorganic filler and the layer of the resin-impregnated base material are not limited as long as the layer of the PPO-based resin composition is inside the layer of the resin-impregnated base material. Therefore, in FIG. 2, there may be two or more PPO-based resin composition sheets 31 containing an inorganic filler, and they may also be arranged between resin-impregnated base materials 41. The number of resin-impregnated base materials 41 may be greater or less.
PPO resin composition sheet 31 and resin-impregnated base material 4
Although the arrangement with the first
As shown in the figure, it is preferable to arrange them vertically symmetrically. At the adhesive interface with the metal foil 21,
In terms of adhesive strength, it is preferable to combine the sheets so that the PPO resin composition sheet 31 is placed on top. The adhesion between the metal foil 21 and the PPO-based resin composition sheet 31 can utilize the thermal fusion properties of the PPO-based resin composition sheet 31, so the heat pressing temperature is higher than the glass transition point of the PPO-based resin composition sheet 31. almost
A range of about 160 to 300°C is preferable. Here, the PPO resin composition used in this invention will be explained. used in this invention
The PPO-based resin composition contains PPO, a crosslinkable polymer and/or a crosslinkable monomer, and an inorganic filler. PPO is, for example, the following general formula, [Here, R represents hydrogen or a hydrocarbon group having 1 to 3 carbon atoms, and each R may be the same,
They can be different. ] An example thereof is poly(2,6-dimethyl-1,4-phenylene oxide). Such PPO can be synthesized, for example, by the method disclosed in USP 4,059,568. For example, poly(2,6-dimethyl-1,4-phenylene oxide) is obtained by subjecting 2,6-xylenol to an oxidative coupling reaction with an oxygen-containing gas and methanol in the presence of a catalyst. , but is not limited to this method. Here, as a catalyst, a copper() compound, N,N'-di-tert
- Contains butylethylenediamine, butyldimethylamine and hydrogen bromide. Based on methanol, 2 to 15% by weight of water is added to the reaction mixture system, so that the total amount of methanol and water becomes 5 to 25% by weight of the polymerization solvent. For example, the weight average molecular weight (Mw) is 50000, the molecular weight distribution Mw/Mn=4.2 (Mn
(number average molecular weight) is preferably used. Examples of crosslinkable polymers include, but are not limited to, 1,2-polybutadiene, 1,4-polybutadiene, styrene-butadiene copolymers, modified 1,2-polybutadiene (malein-modified, acrylic-modified, epoxy-modified ),
Examples include rubbers, and each may be used alone or in combination of two or more. The polymer state may be an elastomer or a rubber, but a high molecular weight rubber state is particularly preferred from the viewpoint of improving film-forming properties. Examples of crosslinkable monomers include ester acrylates, epoxy acrylates, urethane acrylates, ether acrylates,
Acrylates such as melamine acrylates, alkyd acrylates, silicone acrylates, polyfunctional monomers such as triallyl cyanurate, triallyl isocyanurate, ethylene glycol dimethacrylate, divinylbenzene, diallyl phthalate, vinyltoluene, ethylvinylbenzene, styrene , monofunctional monomers such as paramethylstyrene, and polyfunctional epoxies, each of which may be used alone or in combination of two or more, but is not particularly limited to these. However, it is recommended to use triallyl cyanurate and/or triallyl isocyanurate as the crosslinking monomer because it has good compatibility with PPO.
It is preferable in terms of film formability, crosslinkability, heat resistance, and dielectric properties. Triallyl cyanurate and triallyl isocyanurate are chemically structurally isomers, and have almost the same film-forming properties, compatibility, and
Since they have solubility, reactivity, etc., either one or both can be used. The crosslinkable polymer and/or crosslinkable monomer is
By crosslinking (curing), it is used to improve heat resistance etc. without impairing the properties of PPO. These may be used alone or in combination, but their combined use is more effective in improving characteristics. Inorganic fillers include aluminum oxide, silicon dioxide (SiO ₂ ), titanium dioxide (TiO ₂ ), glass fiber, glass chips, barium titanate (BaTiO ₃ ), lead titanate (PbTiO ₃ ), strontium titanate (SrTiO ₃ ). , calcium titanate (CaTiO ₃ ), magnesium titanate (MgTiO ₃ ),
Examples include barium zirconate (BaZrO ₃ ), lead zirconate (PbZrO ₃ ), K ₂ O-PbO-SiO ₂ glass, and solid solutions of lead titanate and lead zirconate, each of which can be used singly or in combination. The above may be used in combination, but is not limited to these. however,
If the resulting printed wiring board material needs to have an extremely high dielectric constant, aluminum oxide, titanium dioxide, silica (silicon dioxide), barium titanate, lead titanate, and other well-known high dielectric constant dielectric materials can be used. to be used as an inorganic filler. The inorganic filler preferably has a size that does not cause any disadvantage to the properties of the printed wiring board material, and is preferably used in the form of fine particles. Preferably, the particle size is about 50 μm or less;
If it is too small, handling may become difficult, so a range of 1 to 20 μm (more preferably 1 to 10 μm) is more preferable.
Note that by adjusting the type and amount of the inorganic filler, it is also possible to adjust the dielectric constant of the printed wiring board material over a wide range. The blending ratio of the above raw materials is not particularly limited, but PPO10 to 95 parts by weight (more preferably 20 to 95 parts by weight)
90 parts by weight), 1 to 50 parts by weight of crosslinkable polymer and/or crosslinkable monomer, and 1 to 200 parts by weight of inorganic filler.
Preferably, it is expressed in parts by weight. When the proportion of the crosslinkable polymer and/or crosslinkable monomer is below the above range, adhesion may become insufficient, and when it exceeds the above range, the characteristics of PPO may not be exhibited. If the ratio of the inorganic filler is below the above range, the effect of adding the inorganic filler may not appear, and if it exceeds the above range, the solidified product of the PPO resin composition may become porous or lose strength. It may begin to exhibit unfavorable trends such as
Further, although not particularly limited, it is preferable to use the crosslinkable polymer in a ratio of 20 parts by weight or less per 1 part by weight of the crosslinkable monomer. In particular, when flakes (inorganic substances) are used as the inorganic filler, the dimensional stability, solvent resistance, warpage, etc. of the solidified PPO resin composition are improved. Examples of the flaky inorganic filler include glass flakes and mica, each of which may be used alone or in combination of two or more, but is not limited thereto. For example, flat glass pieces such as micro glass flakes manufactured by Nippon Glass Fiber Co., Ltd.
Examples include glass flakes having a thickness of 2 to 3 μm and a particle size of 10 to 325 meshes, and/or fine mica particles of 5 to 100 meshes such as Daimonite manufactured by Topy Industries, Ltd. From the viewpoint of electrical properties, mica is preferably muscovite, but is not particularly limited thereto. Note that the flaky inorganic filler preferably has a size of 80 mesh or less. If the size exceeds 80 meshes, when the PPO resin composition is made into a solution as described below, the flaky inorganic filler tends to settle, and the storage stability in the solution may deteriorate. The flaky inorganic filler preferably has an average thickness of 3 μm or less and/or an aspect ratio of 100 or less. If the average thickness is larger than 3 μm and the aspect ratio is larger than 100, when the PPO resin composition is made into a sheet by the casting method as described below, the drying speed will be slow, resulting in poor work efficiency. , the physical properties of the sheet may deteriorate. In addition, from the perspective of improving the dimensional stability of printed wiring board materials, the aspect ratio of the flaky inorganic filler is 10.
It is preferable that it is above. Further, the thickness of the flaky inorganic filler is preferably 1 μm or more. The flaky inorganic filler plays the role of a skeleton that connects the resins in the solidified PPO resin composition, improving the strength of the solidified product, and since it is plate-shaped, it prevents the infiltration of chemicals such as solvents. It also works to prevent Of course, it also contributes to dimensional stability. In addition, an initiator is usually used in PPO resin compositions. As the initiator, the following two types can be selected depending on whether the PPO resin composition is of an ultraviolet curing type or a thermosetting type, but the initiator is not limited to these. Examples of ultraviolet curing photoinitiators (that is, those that generate radicals when exposed to ultraviolet rays) include benzoin, benzyl, allyldiazonium fluoroborate, benzyl methyl ketal, 2,2-diethoxyacetophenone, benzoyl isobutyl ether, p-tert-butyltrichloroacetophenone, benzyl(o-ethoxycarbonyl)-
Examples include α-monoxime, biacetyl, acetophenone, benzophenone, Michler's ketone, tetramethylthiuram sulfide, and azobisisobutyronitrile. Examples of thermosetting initiators (that is, those that generate radicals by heat) include dicumyl peroxide, tert-butylcumyl peroxide, benzoyl peroxide, di-tert-butyl peroxide, and 2,5-dimethyl- 2,5-di-
(tert-butylperoxy)hexyne-3, 2,
5-dimethyl-2,5-di-(tert-butylperoxy)hexane, α,α'-bis(tert-butylperoxy-m-isopropyl)benzene [1,
4 (or 1,3)-bis(tert-butylperoxyisopropyl)benzene], 1-hydroxycyclohexyl phenyl edone, 2-hydroxy-2-methyl-1-phenyl-propane-1 -one, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, 2-chlorothioxanthone, methylbenzoylformate, 4,4-bisdimethylaminobenzophenone (Michler ketone),
Benzoin methyl ether, methyl-o-benzoylbenzoate, α-acyloxime ester,
Examples include Nippon Oil & Fats Co., Ltd.'s Biscum Mill. The initiator is
Each may be used alone or in combination of two or more. A UV initiator and a thermal initiator may be used in combination. The blending ratio of the initiator is preferably 0.1 to 5 parts by weight (more preferably 0.1 to 3 parts by weight) with respect to the raw material blending ratio. If the proportion of the initiator is below the above range, the PPO resin composition may not be sufficiently cured, and if it exceeds the above range, the physical properties after curing may be adversely affected. When producing printed wiring board materials, PPO-based resin compositions are heated, and if a cross-linking reaction using a radical initiator is carried out during this heating, even stronger adhesion can be obtained. The crosslinking reaction may be carried out by ultraviolet irradiation or the like. thermal crosslinking,
When photocrosslinking is not performed, crosslinking may be performed by radiation irradiation. Furthermore, after thermal crosslinking and photocrosslinking, crosslinking by radiation irradiation may be performed. In addition, as a raw material for PPO resin compositions,
Polystyrene may also be used. It is preferable to use polystyrene because when the PPO-based resin composition is formed into a sheet by the casting method described below, the film-forming property is improved. From the point of view of improving film-forming properties, it is more preferable to use high molecular weight polystyrene. In addition, when PPO is used together with polystyrene and/or styrene-butadiene copolymer, it is preferable to set the blending weight ratio of parts by weight of PPO/parts by weight of polystyrene+parts by weight of styrene-butadiene copolymer≧1. The raw materials for the PPO resin composition described above are blended in a predetermined ratio, usually dissolved and dispersed in a solvent (inorganic fillers usually do not dissolve), and mixed (solution mixing). be done. In this case, the solvent
Resin solid content is 10-30% by weight compared to 100% by weight
It is preferable to set it as the range of. After mixing, a PPO resin composition is obtained by removing the solvent.
Examples of the solvent include halogenated hydrocarbons such as trichloroethylene, trichloroethane, chloroform, methylene chloride, tetrachloroethylene, and chlorobenzene, aromatic hydrocarbons such as benzene, toluene, and xylene, acetone, and carbon tetrachloride, and trichloroethylene is particularly preferred. These can be used alone or in combination of two or more, but are not limited thereto. Note that the mixing may be done by other methods. PPO resin compositions are produced by, for example, dissolving raw materials in a solvent and mixing them as described above, casting or coating them on an appropriate object to form a thin layer, and then drying to remove the solvent. By this method (casting method), it can be made into a solidified product. According to this casting method, a solidified product of the PPO resin composition can be produced at a low temperature without using the costly calendar method.
By such a casting method, the PPO resin composition sheet 31 in the above embodiment is produced. As described above, the PPO resin composition sheet 31 in the above embodiment can be made by the casting method, but it may be made by a method other than this method. When using a casting sheet as a PPO resin composition sheet, dry it thoroughly at a temperature lower than the decomposition temperature of the initiator blended and higher than the boiling point of the solvent used to eliminate residual solvent. Let's do it like this. To explain the casting method in detail,
A solution prepared by dissolving the PPO resin composition or its raw material in the above-mentioned solvent at a ratio of, for example, 5 to 50% by weight is placed on a mirror-treated iron plate or a carrier film for casting, etc. The sheet is obtained by casting (or coating) to a thickness of ~700 (preferably 5 to 500) μm, and thoroughly drying to remove the solvent. Note that sheet here refers to film,
Including what is called a film, tape, etc., there are no particular limitations on the extent and length of the surface perpendicular to the thickness direction, and the thickness can also be set in various ways depending on the application. The carrier film for casting is not particularly limited, but it is preferable to use one that is insoluble in the above solvents, such as polyethylene terephthalate (hereinafter abbreviated as "PET") film, polyethylene film, polypropylene film, polyester film, and polyimide film. , and is preferably subjected to mold release treatment. The solvent of the PPO resin composition solution cast (or coated) on a carrier film for casting is removed by air drying and/or drying with hot air. The upper limit of the set temperature during drying is preferably lower than the boiling point of the solvent or lower than the heat-resistant temperature of the carrier film for casting (when drying is performed on the carrier film for casting); The lower limit is determined by drying time, processability, etc. For example, if trichlorethylene is used as a solvent,
When a PET film is used as a carrier film for casting, the temperature range is preferably from room temperature to 80°C, and if the temperature is raised within this range, the drying time can be shortened. In addition, the PPO resin composition sheet produced in this way can be further improved in tensile strength, by thermal crosslinking using a radical initiator, photocrosslinking, crosslinking using radiation, etc. impact strength,
It can improve bursting strength, heat resistance, etc. The resin-impregnated base material impregnated with the above-mentioned PPO resin composition may be produced by any method, but
Generally, it can be made by the following method. In other words, the PPO resin composition or its raw material,
For example, the base material is completely dissolved in the above solvent at a ratio of 5 to 50% by weight (inorganic fillers usually do not dissolve), and the base material is immersed (dipped) in this solution. These PPO resin compositions are impregnated and attached. In this case, the solvent may be simply removed by drying or the like, or it may be semi-cured to bring it to the B stage. The base material may be a resin-impregnated cloth such as glass cloth, aramid cloth, polyester cloth, or nylon cloth, a pine-like material made of these materials and/or a fibrous material such as nonwoven fabric, kraft paper,
Paper such as linter paper can be used, but is not limited thereto. If the resin-impregnated base material is produced in this way, the resin does not need to be melted, so it can be done more easily at a relatively low temperature. The resin-impregnated base material for forming the layer 4 of the resin-impregnated base material is a base material impregnated with a resin other than the PPO-based resin composition, and the resin other than the PPO-based resin composition includes: For example, a thermosetting resin such as epoxy resin or polyimide resin is used. In addition, base materials include cloth-like materials that can be impregnated with resin such as glass cloth, aramid cloth, polyester cloth, and nylon cloth, pine-like materials made of these materials and/or fibrous materials such as nonwoven fabrics, kraft paper, and linter paper. Use paper such as . As the conductor layer 2, for example, there is a metal layer,
As the metal layer, for example, metal foil such as copper foil or aluminum foil is used. It is preferable that the metal foil has a smooth adhesion surface and good conductivity in order to improve dielectric properties. The conductor layer 2 may be formed after the insulating substrate 1 is formed. In this case, it is formed by, for example, a subtractive method, an additive method (a full additive method, a semi-additive method), or the like. The conductor layer 2 is the insulating substrate 1
It may be formed on one side, both sides, or it may not be formed. As seen above, in the printed wiring board material according to the present invention, the insulating substrate 1 is impregnated with a layer 3 of a PPO resin composition containing an inorganic filler and a resin other than the PPO resin composition. Base material layer 4
It is made up of. Layer 3 of the PPO-based resin composition containing an inorganic filler contains an inorganic filler with a high dielectric constant, so it is a layer with a high dielectric constant. Therefore,
The printed wiring board material according to the present invention has a layer 3 of a PPO resin composition containing an inorganic filler in an insulating substrate 1, and therefore has a high dielectric constant. Moreover, since the insulating substrate 1 is an organic substrate, the processability is also good. Furthermore, in the printed wiring board material of the present invention, a layer of a PPO resin composition containing an inorganic filler is provided on the inside.
Since the resin-impregnated base material layer impregnated with a resin other than the PPO-based resin composition is placed on the outside, it is sufficient in terms of practicality. The outer resin-impregnated base material layer can compensate for the weaknesses of the inner PPO resin composition layer. Next, Examples and Comparative Examples will be shown. (Example 1) A PPO resin composition solution was obtained with the formulation shown in Table 1. The obtained PPO resin composition solution was coated onto a PET film using a coating machine to a thickness of 500 μm. After baking and drying this at 60℃ for 10 minutes, the resulting film was released from the PET film and baked at 120℃ for 15 minutes.
It was dried at 210°C for 15 minutes to completely remove trichlorethylene to obtain a PPO resin composition sheet.
The thickness of this sheet was 250 μm. As shown in FIG. 2, this sheet 31 and
A resin-impregnated base material (100 μm thick) 41 made by impregnating glass cloth (WE05E manufactured by Nittobo Co., Ltd., 50 μm thick) with epoxy resin and copper foil (35 μm thick) 21 were heated at 170°C, 30 kg/cm ² for 60 minutes. A printed broken line board material was obtained by lamination molding under the following conditions. (Example 2) A PPO resin composition sheet having a thickness of 200 μm was obtained in the same manner as in Example 1 using the formulations shown in Table 1. Thereafter, a printed wiring board material was obtained in the same manner as in Example 1 except that the configuration was changed to that shown in FIG. (Example 3) In the same manner as in Example 1, using the formulation shown in Table 1.
A PPO resin composition solution was obtained. A glass cloth (WE05E manufactured by Nittobo Co., Ltd., thickness 50 μm) was impregnated with the obtained PPO resin composition solution and heated at 60°C for 4 hours.
The substrate was dried at 100° C. for 9 minutes to obtain a PPO-based resin composition-impregnated base material with a resin content of about 60% and a thickness of 60 μm. As shown in FIG. 4, this PPO resin composition-impregnated base material 32, resin-impregnated base material 41, and copper foil 21 were laminated and molded under the same conditions as in Example 1.
A printed wiring board material was obtained. (Example 4) A printed wiring board material was obtained in the same manner as in Example 3, except that the formulation was as shown in Table 1 and the composition was as shown in FIG. 5. (Example 5) In the same manner as in Example 3, using the formulation shown in Table 1.
A base material impregnated with a PPO resin composition was obtained. As shown in Fig. 6, this PPO resin composition impregnated base material 32 and a polyimide resin are coated with glass cloth (WE05E manufactured by Nittobo Co., Ltd., thickness 50 μm).
A resin-impregnated base material (thickness 100 μm) 42 impregnated with
Copper foil (thickness 35μm) 21 and 220℃, 40Kg/cm ² , 90
A printed wiring board material was obtained by lamination molding under conditions of 1 minute. (Comparative example 1) The insulating substrate is made of 92% pure alumina,
A printed wiring board material with a thickness of 1 mm that has copper foil on both sides of the insulating substrate. (Comparative Example 2) A printed broken wire board material with a thickness of 0.8 mm, in which the insulating substrate is composed only of a resin-impregnated base material made by impregnating glass cloth with epoxy resin, and copper foil is stretched on both sides of the insulating substrate. (Comparative Example 3) A printed wiring board material with a thickness of 0.8 mm, in which the insulating substrate is composed only of a resin-impregnated base material made by impregnating glass cloth with polyimide resin, and copper foil is stretched on both sides of the insulating substrate. In Table 1, SBS is a styrene-butadiene copolymer, A is Sorprene T406 manufactured by Asahi Kasei Corporation, B is Tuffrene A manufactured by Asahi Kasei Corporation, and C is triallyl isocyanurate (TAIC manufactured by Nippon Kasei Corporation). , D is 2,5-dimethyl-2,5-di-(tert-butylperoxy)
Hexine-3 (Perhexine manufactured by Nippon Oil & Fats Co., Ltd.)
25B), E is trichlorethylene (Toriclean manufactured by Toagosei Chemical Industry Co., Ltd.), F is titanium dioxide,
G is aluminum oxide. As described above, the dielectric constants at 1 MHz were measured for the printed wiring board materials of Examples 1 to 5 and Comparative Examples 1 to 3, and the drillability was also examined. The results are shown in Table 2.

【table】

【table】

〔Effect of the invention〕

Since the printed wiring board material according to the present invention has the configuration as described above, it has the following effects of good processability, and
It has the effect of making it possible to miniaturize the circuit used in the UHF or SHF band, and also has the effect of being sufficiently practical. Remarkable. Effects The printed wiring board material of the present invention has excellent workability because it is an organic substrate with good workability. Effect: The printed wiring board material of this invention
The high dielectric constant makes it possible to miniaturize circuits used in the UHF or SHF bands.
The layer of the PPO resin composition contains an inorganic filler with a high dielectric constant, and this inorganic filler is interposed in layers in the thickness direction of the insulating substrate, increasing the dielectric constant of the wiring board material. . Effects One reason why the printed wiring board material is sufficiently practical is that the low loss characteristics of the PPO resin composition are fully utilized. PPO
Since the PPO-based resin composition is present as a layer in the thickness direction of the insulating substrate, the low dielectric loss characteristic of the PPO-based resin composition is directly reflected in the insulating substrate of the printed wiring board material. Another reason is that a resin-impregnated base material layer impregnated with a resin other than the PPO resin composition is disposed outside the PPO resin composition layer, which can compensate for the weaknesses of the PPO resin composition.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing one embodiment of the printed wiring board material according to the present invention, FIG. 2 is a schematic diagram showing an example of the state of the embodiment before manufacturing, and FIGS. 3 to 6 2A and 2B are schematic diagrams each schematically showing an example of a state before manufacture of different embodiments. 1... Insulating substrate, 3... Contains inorganic filler
Layer of PPO resin composition, 4...layer of resin-impregnated base material.

Claims (1)

[Claims] 1 The insulating substrate is a layer of a polyphenylene oxide resin composition containing polyphenylene oxide, a crosslinkable polymer other than a polyfunctional maleimide type and/or a crosslinkable monomer other than a polyfunctional maleimide type, and an inorganic filler. , a layer of a resin-impregnated base material impregnated with a resin other than the polyphenylene oxide-based resin composition, the resin-impregnated base material being on the outside and the layer of the polyphenylene oxide-based resin composition being on the inside, respectively. A printed wiring board material composed of: