JP2006128360A - Printed wiring board and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To thin a printed wiring board much more by not only thinning a structure material of the board but also reviewing a construction. <P>SOLUTION: Insulating films 31 and 41 of a laminated plate for making multiple layers are extended to a cable B of a base substrate. The insulating films 31 and 41 protect and cover conductive layers 12 and 13 of the cable B, and a cover lay is omitted. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a printed wiring board and a manufacturing method thereof, and more particularly to a printed wiring board having a multilayer portion in a partial region of a base substrate such as a rigid-flex board and a manufacturing method thereof.

  As a printed wiring board used in an electronic device, a partial region on a surface of a base substrate having a conductive layer made of copper foil or the like on at least one surface of a flexible insulating base film such as polyimide. In order to make a multilayer, a laminated board having a conductor layer is laminated on at least one surface of the insulating film, and a rigid multilayer part is formed by the conductor layer of the base substrate and the conductor layer of the laminated board, A rigid-flex board having a flexible cable portion for conductive connection by the conductor layer of the base board is known (for example, Non-Patent Documents 1 and 2).

  A specific example (six layers) of a conventional rigid-flex board will be described with reference to FIG.

  The rigid-flex 6-layer substrate is made of copper foil on both sides of the FPC inner layer CCL (copper-clad laminate) 100, that is, the polyimide film 101, as a base substrate at the center (center in the stacking direction) as seen in a cross-sectional view. A double-sided copper-clad inner layer CCL100 having conductor patterns 102 and 103 is disposed, and CLs (coverlays) 110 and 120 are respectively disposed on the entire surfaces of both surfaces. The CLs 110 and 120 have adhesive layers 112 and 122 on one side of a cover film 111 and 121 made of polyimide or the like, and are bonded to the surface of the CCL 100 by the adhesive layers 112 and 122, respectively.

  Further, on the outer (outer layer side) partial region (on the left and right sides in the cross-sectional view), double-sided copper-clad outer layer CCL140 is provided via interlayer adhesive sheets (interlayer adhesive) 131, 132 and prepregs 133, 134. , 150 are stacked. In the outer layers CCL 140 and 150, conductor patterns 142, 143, 152, and 153 made of copper foil are formed on both surfaces of the insulating films 141 and 151, respectively.

  Thereby, the multilayer part A by the inner layer CCL100 and the outer layers CCL140 and 150 and the flexible cable part B for conductive connection by the inner layer CCL100 are configured.

  In the multilayer portion A, plated through holes 135 and 136 for interlayer conduction are formed. Then, permanent resist layers (insulating layers) 137 and 138 for circuit protection are formed on the outermost layer.

  The manufacturing process of this rigid-flex 6-layer substrate is, for example, as follows.

(1) As a base substrate disposed in the center, circuit formation (formation of conductor patterns 102 and 103) on both surfaces of the inner layer CCL100 for FPC is performed, and CL110 and 120 are bonded to both surfaces.

(2) The outer layers CCL 140 and 150 form circuits (conductor patterns 142 and 152) located on the inner layer CCL 100 side, and the outer layers CCL 140 and 150 are connected to (1) via the interlayer adhesive sheets 131 and 132 and the prepregs 133 and 134. Paste. Thereby, the multilayer part A is formed.

(3) A through hole is made in order to establish mutual conduction between the interlayer circuits of the multilayer portion A, and copper plating is performed on the copper foil surface and the through hole to form plated through holes 135 and 136.

(4) Circuit formation of the outermost layer (formation of conductor patterns 143 and 153) is performed by the outer layers CCL 140 and 150, and permanent resist layers (solder resist layers) 137 and 138 are further provided to complete a rigid-flex 6-layer substrate. .

  In the case of a rigid-flex 6-layer substrate, the prepregs 133 and 134 can be omitted, and lamination can be performed only through the interlayer adhesive sheets 131 and 132. Further, in the case of an FPC multilayer substrate, the prepregs 133 and 134 are omitted, and the same FPC substrate as the inner layer CCL 100 is used as the outer layers CCL 140 and 150.

  This type of multilayer board is characterized in that the multilayer part A and the cable part B are integrally provided and the cable part B is flexible.

  These multilayer substrates are laminated with an interlayer adhesive, a prepreg, or the like as described in the above process, but it is necessary to suppress the seepage of the adhesive at the boundary portion C between the multilayer portion A and the cable portion B. The interlayer adhesive needs to ensure circuit filling properties in the multilayer part A, and preferably has a low melt viscosity when uncured. However, if the melt viscosity of the interlayer adhesive is too low, the amount of seepage at the boundary portion C between the multilayer portion A and the cable portion B increases during lamination, and the flexibility of the cable portion B may be impaired.

  For this, in order to ensure circuit fillability and suppress resin flow, it is generally possible to adjust the melt viscosity of the adhesive or prepreg material or prevent it by combining the cushion material used at the time of bonding. In addition to this, proposals have been made to prevent the outflow of resin to the cable part by providing a dummy pattern at the boundary part or arranging a dam material for preventing resin flow at the boundary part (for example, Patent Documents 1 and 2).

  In recent years, electronic devices are becoming smaller and thinner, and printed circuit boards mounted on electronic devices are required to be thinner. Conventional multilayer substrate structures have limitations.

  In order to make the substrate thinner with the conventional structure, it is necessary to make the material used thinner. For example, the following materials are used for the multilayer substrate.

(1) CCL (polyimide film and circuit copper foil)
As the polyimide film, a material having a thickness of 25 μm (lmil) is generally used. 12.5 μm (1/2 mil) is also used as a thin substrate. The copper foil has a standard of 35 μm (1 oz) and includes 18 μm (1/2 oz), 12 μm (1/3 oz), 9 μm (1/4 oz), and the like. For example, if the polyimide film is 1/2 mil and the copper foil is 1/4 oz, a CCL with a total thickness of 21.5 μm is realized, but the thin copper foil is expensive, the CCL is difficult to manufacture, and the material cost is high. . Moreover, since it is thin, handling is difficult, and it is easy to generate | occur | produce the defect by bending and a wrinkle by manual work.

(2) CL (polyimide fill and adhesive layer)
Like CCL, lmil material is generally used for polyimide film, but 1/2 mil material is also used as a thin substrate. The adhesive can be processed to an arbitrary thickness, and it is desirable that the adhesive is thicker than the circuit copper foil in order to fill between the circuits.

(3) Glass fiber reinforced epoxy resin board (GE board)
Although there is a thin substrate of about 60 μm, there is a limit to making it thin because a glass fiber is sandwiched in the center.

(4) Adhesive used for adhesion between layers Like the adhesive for CL, it can be processed to an arbitrary thickness, and is desired to be thicker than the circuit copper foil in order to fill between circuits.

(5) Copper plating for indirect layer traversal In order to ensure connection reliability, there is a limit to thinning. The critical thickness also depends on the material and thickness of the substrate and the quality of the hole. In general, as the substrate becomes thinner, the plating thickness can be reduced.

(6) Surface permanent resist layer A certain thickness is required to protect the surface layer circuit and depends on the circuit thickness.

All materials are required to have a certain thickness to ensure productivity, cost, and performance. In addition, with regard to measures to prevent the resin from flowing from the multilayer part to the cable part, in each case, a dummy process that adjusts the viscosity of the resin, a dam material, etc. are required, and a process different from normal is required, which increases the cost. It becomes.
Japan CMK website [October 1, 2004 search] Internet <URL: http://www.cmk-corp.com/html/product/prod_rf_idx.html, http://www.cmk-corp.com/pdf /products/RigidFlex0306.pdf> Nippon Mektron Home Page [October 1, 2004 search] Internet <URL: http://www.mektron.co.jp/fb/index.html, http://www.mektron.co.jp/fbb/ index.html> JP 2001-156445 A JP 2001-185854 A

  In view of the above, the problem to be solved by the present invention is not only to make the constituent material of the substrate thin, but also to review the structure to make it thinner.

  The printed wiring board according to the present invention is formed on at least one surface of the insulating film in order to multilayer the partial region on the surface of the base substrate having the conductor layer on at least one surface of the insulating base film. Printed wiring comprising a laminated board having a conductor layer, and having a multilayer part formed by the conductor layer of the base board and the conductor layer of the laminated board, and a cable part for conducting connection by the conductor layer of the base board. In the board, the insulating film of the laminated plate for multilayering extends to the cable portion of the base substrate, and the insulating film protects and covers the conductor layer of the cable portion. There is no.

  In the printed wiring board according to the present invention, preferably, the entire surface of the insulating film of the laminated board is bonded to the surface of the base substrate on the conductor layer side by an adhesive layer.

  In the printed wiring board according to the present invention, preferably, both the base film of the base substrate and the insulating film of the laminated board are made of a flexible resin film.

  In the printed wiring board according to the present invention, preferably, a prepreg is laminated on the multilayer portion.

  In the printed wiring board manufacturing method according to the present invention, the insulating film is formed on a surface of the base substrate having a conductor layer on at least one side of the insulating base film. A laminated board having a conductor layer on at least one surface is bonded, a multilayer part is formed by the conductor layer of the base board and the conductor layer of the laminated board, and the other part is conducted by the conductor layer of the base board. It has a lamination curing process as a cable part for connection, the insulating film of the laminated board extends to the cable part of the base substrate, the insulating film in the lamination curing process Affixed to the cable part, the conductor layer of the cable part is protectively covered with the insulating film.

  In the printed wiring board according to the present invention, in the printed wiring board in which the multilayer portion and the cable portion are integrally formed, the protective covering of the cable portion is performed by an insulating film constituting the multilayer portion, and the protective covering of the cable portion is eliminated. Therefore, the material cost for the coverlay is reduced, the cost is reduced, and the substrate can be easily made thinner.

  An embodiment in which the printed wiring board according to the present invention is applied as a rigid-flex 6-layer substrate will be described with reference to FIG.

  The rigid-flex 6-layer substrate of this embodiment has an inner layer CCL (copper-clad laminate) 10 for FPC as a base substrate at the center (center in the stacking direction) as viewed in a cross-sectional view, that is, a flexible resin film. The polyimide film (polyimide base material) 11 is a double-sided copper-clad inner layer CCL10 in which conductor patterns 12 and 13 made of copper foil are formed on both sides.

  In the partial areas (both left and right sides in the cross-sectional view) of the inner layer CCL 10, the outer layers CCL 30, 40 of copper-clad on both sides are provided via the interlayer adhesive sheets 21, 22 made of epoxy adhesive and epoxy prepregs 23, 24. Are stacked.

  The outer layers CCL 30 and 40 are copper-clad laminates for multilayering, and conductive patterns 32, 33 and 42 made of copper foil on both surfaces of polyimide films (polyimide base materials) 31 and 41, which are flexible resin films, respectively. , 43 are formed.

  Thereby, the multilayer part A by the inner layer CCL10 and the outer layers CCL30 and 40 and the flexible cable part B for conductive connection by the inner layer CCL10 are configured.

  The multilayer portion A is formed with plated through holes 25 and 26 for surface layer conduction and surface vias 27 and 28.

  In the outermost layer, permanent resist layers (insulating layers) 51 and 52 for circuit protection are formed.

  The polyimide films 31 and 41 of the outer layers CCL30 and 40 extend to the cable portion B of the inner layer CCL10 that forms the base substrate, and the cable corresponding portions 31B and 41B are formed on both surfaces of the inner layer CCL10 including the cable portion B. It is bonded to the surface of the cable portion B by the cable corresponding portions 21B and 22B of the provided interlayer adhesive sheets 21 and 22.

  Thereby, the polyimide films 31 and 41 of the outer layers CCL 30 and 40 form a cover film that protects and covers the conductor patterns (conductor layers) 12 and 13 of the cable part A.

  In the rigid-flex board having this structure, a CL (cover lay) for protecting and covering the conductor pattern of the cable portion B is not required, and CL is uniformly laminated on the multilayer portion A and the cable portion B (FIG. 8). The multilayer portion A can be made thinner by the amount of omission of CL110 and 120). Compared to the conventional example, for example, when CL having a polyimide film of 25 μm and an adhesive layer of 25 μm is used, the multilayer portion A can be thinned by 100 μm in total on both sides. Further, CL is not necessary, and the material cost can be reduced.

  The interlayer adhesive sheets 21 and 22 are all disposed inside the outer layers CCL 30 and 40 and are not exposed to the outside of the substrate. For this reason, the seepage of the interlayer adhesive sheets 21 and 22 can be suppressed under normal lamination conditions, and the flexibility at the boundary portion is improved.

  The prepregs 23 and 24 are used when the mechanical strength of the multilayer portion A is required (rigidization), and can be thinned as necessary. Further, it can be omitted. Alternatively, the interlayer adhesive sheets 21 and 22 in the multilayer part A are eliminated, and only the prepregs 23 and 24 are provided, and the interlayer adhesive sheets 21 and 22 for attaching the polyimide films 31 and 41 only to the cable part B (only the parts 21B and 22B). May be provided.

  Next, an example of a manufacturing process of the rigid-flex 6-layer substrate of the present embodiment will be described with reference to FIGS.

(Manufacture of base substrate)
As shown in FIG. 2 (a), starting from a double-sided copper clad laminate 19 having copper foils 14 and 15 on both sides of the polyimide film 11, as shown in FIG. 2 (b), The copper foils 14 and 15 are etched to form conductor patterns 12 and 13 to complete the inner layer CCL10 as a base substrate.

(Manufacture of upper laminated board)
As shown in FIG. 3 (a), starting from a double-sided copper-clad laminate 39 having copper foils 34, 35 on both sides of the polyimide film 31, as shown in FIG. 3 (b), The conductor pattern 33 is formed by etching the lower copper foil 35. The double-sided copper-clad laminate 39 has the same size as the double-sided copper-clad laminate 19 for the base substrate, and the conductor pattern 33 of the double-sided copper-clad laminate 39 is formed only in the multilayer corresponding part Aa, All the Ba copper foil 35 is removed.

  Then, as shown in FIG. 3C, a prepreg having a size corresponding to the size of the multilayer corresponding portion Aa is formed on the conductor pattern 33 side of the multilayer corresponding portion Aa of the double-sided copper-clad laminate 39. Laminate 23. The prepreg 23 exists only in the multilayer corresponding part Aa.

  Next, as shown in FIGS. 3D and 3E, on the side of the prepreg 23 of the double-sided copper-clad laminate 39, the same size as the double-sided copper-clad laminate 39, in other words, for the base substrate An interlayer adhesive sheet 21 having the same size as the double-sided copper-clad laminate 19 is laminated.

  The interlayer adhesive sheet 21 may be laminated on the conductor pattern 12 side of the inner layer CCL10.

(Manufacture of laminated board for lower multilayer)
As shown in FIG. 4A, starting from a double-sided copper clad laminate 49 having copper foils 44 and 45 on both sides of the polyimide film 41, as shown in FIG. The conductor pattern 42 is formed by etching the upper copper foil 44. The double-sided copper-clad laminate 49 also has the same size as the double-sided copper-clad laminate 19 for the base substrate, and the conductor pattern 42 of the double-sided copper-clad laminate 49 is formed only in the multilayer corresponding part Ab, All the copper foil 44 of Bb is removed.

  Then, as shown in FIG. 4C, a prepreg having a size corresponding to the size of the multilayer corresponding part Ab is formed on the side of the conductor pattern 42 of the multilayer corresponding part Ab of the double-sided copper-clad laminate 49. Laminate 24. The prepreg 24 exists only in the multilayer corresponding part Ab. The multi-layer corresponding portions Aa and Ab have the same size.

  Next, as shown in FIGS. 4D and 4E, on the side of the prepreg 24 of the double-sided copper-clad laminate 49, the same size as the double-sided copper-clad laminate 49, that is, both sides for the base substrate. An interlayer adhesive sheet 22 having the same size as the copper-clad laminate 19 is laminated.

  The interlayer adhesive sheet 22 may be laminated on the conductor pattern 13 side of the inner layer CCL10.

(Laminated)
As shown in FIG. 5A, the laminated plate 38 of FIG. 3E is arranged above the inner layer CCL10, and the laminated plate 48 of FIG. 4E is arranged below the inner layer CCL10. As shown in FIG. 5B, these are laminated and cured together. This lamination curing is performed by heating and pressurizing the laminated body of the laminated plate 38, the inner layer CCL10, and the laminated plate 48 with a hot press machine so that the interlayer adhesive sheets 21, 22, and the prepregs 23, 24 are cured to the C stage state. .

  Thereby, the multilayer part A by the inner layer CCL10 and the laminated plates 38 and 48 and the flexible cable part B for conductive connection by the inner layer CCL10 are configured.

  By this lamination curing, the polyimide film 31 (cable corresponding portion 31B) of the upper laminated plate 38 is tightly bonded to the upper surface of the inner layer CCL10 by the cable corresponding portion 21B of the interlayer adhesive sheet 21 in the cable portion B portion. Further, the polyimide film 41 (cable corresponding portion 41B) of the lower laminated plate 48 is tightly bonded to the lower surface of the inner layer CCL10 by the cable corresponding portion 22B of the interlayer adhesive sheet 22 in the cable portion B portion.

  Next, as shown in FIG. 6C, interlayer conduction holes 61 and 62 penetrating the multilayer portion A are opened. Further, drilling of the surface via holes 63 and 64 for partial interlayer conduction is performed as necessary.

  Next, as shown in FIG. 6 (d), copper plating is performed to obtain interlayer conduction in the interlayer conduction holes 61 and 62 and the surface via holes 63 and 64 by the copper plating layers 65 and 66.

  Next, as shown in FIG. 7 (e), the copper foil 34 and the copper plating layer 65 of the upper laminated plate 38 are etched to form the uppermost outermost conductor pattern 32, and the lower The copper foil 45 and the copper plating layer 66 of the laminated plate 38 are etched to form the lowermost outermost conductor pattern 42. At the same time, plated through holes 25 and 26 and surface layer vias 27 and 28 for interlayer conduction in the multilayer part A are completed.

  The copper foil 34 and the copper plating layer 65 of the upper laminated plate 38 and the copper foil 45 and the copper plated layer 66 of the lower laminated plate 38 are all removed in the cable portion B. Thereby, the polyimide films 31 and 41 remain in the cable part B, and the polyimide films 31 and 41 form a cover film that protects and covers the cable part B, so that the flexibility of the cable part B is ensured.

  Next, as shown in FIG. 7 (f), the outermost layer surface is covered with permanent resist layers 51 and 52, and the exposed surface is subjected to the necessary surface treatment to complete a rigid-flex 6-layer substrate.

  In the case of the cable part B double-sided structure, the rigid-flex board manufactured with such a configuration can be thinned by CL × 2.

The characteristics of the substrate produced as described below were evaluated. Characteristic evaluation was performed about the amount of the adhesive oozing out to the cable part, flexible interlayer connection reliability, and migration resistance.

  For the evaluation of flexibility, a folding resistance test (JISC5016) was performed. The number of times of bending and disconnection at the boundary between the multilayer portion and the cable portion was measured with a radius of curvature of 3 mm. This is a relative evaluation in which the number of times of Comparative Example 2 is 1. For the evaluation of interlayer connection reliability, a gas phase heat shock test was performed (−25 ° C./125° C./60 minutes cycle × 1000 times). It was observed that there was no disconnection in the conductor resistance measurement of the through-hole portion. Evaluation of migration resistance is a high-temperature, high-humidity DC voltage application test (85 ° C / 85RH% / DC50V x 1000 hours) L / S = 100μm / 100μm comb-teeth electrode pattern (total circuit length 2m), insulation resistance measurement 10MΩ or more It was.

Example 1
Structure: Rigid-Flex 6-layer substrate shown in Fig. 1 Material structure used / Permanent resist layer: Alkali-developable dry film type solder resist (38μm thickness)
-Outer layer CCL: electrolytic copper foil (12 μm thickness), polyimide substrate (25 μm thickness)
・ Prepreg: Epoxy prepreg material (60μm thick)
・ Interlayer adhesive sheet: Epoxy adhesive (25μm thick)
Inner layer CCL: rolled copper foil (12 μm thickness), polyimide substrate (25 μm thickness)
・ Interlayer connection: Copper plating (25μm thickness)
(Example 2)
Structure: FPC 6-layer substrate obtained by removing the prepreg layer from the rigid-flex 6-layer substrate shown in FIG. 1. Material structure used: Permanent resist layer: Same as Example 1. Outer layer CCL: Same as Example 1. Interlayer adhesive sheet: Epoxy Adhesive (40μm thickness)
Inner layer CCL: Same as Example 1. Interlayer connection: Same as Example 1 (Example 3)
Structure: Rigid-flex 6-layer substrate in which the interlayer adhesive layer is removed from the rigid-flex 6-layer substrate shown in FIG. 1 only in the multilayer part. Permanent resist layer: same as Example 1. Outer layer CCL: Same as Example 1. Interlayer Adhesive sheet: Same as Example 1. Inner layer CCL: Same as Example 1. Prepreg: Same as Example 1. Interlayer connection: Same as Example 1 (Comparative Example 1): Gid-Flex 6-layer substrate shown in FIG. Material composition used: Permanent resist layer: Same as Example 1. Outer layer CCL: Same as Example 1. Prepreg: Same as Example 1. Interlayer adhesive sheet: Same as Example 1. CL: Epoxy adhesive (25 μm Thickness), polyimide substrate (25 μm thickness)
Inner layer CCL: Same as Example 1 Interlayer connection: Same as Example 1 (Comparative Example 2): FPC 6-layer substrate obtained by removing the prepreg layer from the Gid-Flex 6-layer substrate shown in FIG. 8 Material composition used Permanent resist Layer: Same as Example 1. Outer layer CCL: Same as Example 1. Interlayer adhesive sheet: Same as Example 1. CL: Same as Example 1. Inner layer CCL: Same as Example 1. Interlayer connection: Example 1 Same as

Table 1 shows the evaluation results of Examples 1 to 3 and Comparative Examples 1 and 2.

  As is apparent from Table 1, in Examples 1 to 3, the substrate thickness (thickness of the multilayer part) is reduced as compared with Comparative Examples 1 and 2, and no bleeding of the adhesive to the cable part occurs. Bendability (flexibility) was improved at the boundary between the multilayer part and the cable part. About interlayer connection reliability and migration resistance, the performance equivalent in Examples 1-3 and Comparative Examples 1 and 2 was acquired.

It is sectional drawing which shows one embodiment by applying the printed wiring board by this invention as a rigid-flex 6 layer board | substrate. (A), (b) is process drawing which shows the manufacturing process example (manufacture of a base substrate) of the rigid-flex 6 layer board | substrate of this embodiment. (A)-(e) is process drawing which shows the manufacturing process example (manufacture of the laminated board for upper multilayering) of the rigid-flex 6 layer board | substrate of this embodiment. (A)-(e) is process drawing which shows the manufacturing process example (manufacture of the laminated board for lower multilayering) of the rigid-flex 6 layer board | substrate of this embodiment. (A), (b) is process drawing which shows the manufacturing process example (lamination | stacking) of the rigid-flex 6 layer board | substrate of this embodiment. (C), (d) is process drawing which shows the manufacturing process example (lamination | stacking) of the rigid-flex 6 layer board | substrate of this embodiment. (E), (f) is process drawing which shows the manufacturing process example (lamination | stacking) of the rigid-flex 6 layer board | substrate of this embodiment. It is sectional drawing which shows the prior art example of a rigid-flex 6 layer board | substrate.

Explanation of symbols

10 Inner layer CCL
DESCRIPTION OF SYMBOLS 11 Polyimide film 12, 13 Conductor pattern 14, 15 Copper foil 19 Double-sided copper clad laminated board 21, 22 Interlayer adhesive sheet 23, 24 Prepreg 25, 26 Plating through-hole 27, 28 Surface layer via 30 Outer layer CCL
31 Polyimide film 32, 33 Conductor pattern 34, 35 Copper foil 38 Laminated board 39 Double-sided copper clad laminated board 40 Outer layer CCL
41 Polyimide film 42, 43 Conductor pattern 44, 45 Copper foil 48 Laminate plate 49 Double-sided copper clad laminate 51, 52 Permanent resist layer 61, 62 Interlayer conduction hole 63, 64 Surface via hole 65, 66 Copper plating layer

Claims (5)

Laminate a laminated board having a conductor layer on at least one side of the insulating film in order to multilayer the partial area on the surface of the base substrate having the conductor layer on at least one side of the insulating base film. And a printed wiring board having a multilayer portion formed by the conductive layer of the base substrate and the conductive layer of the laminated plate, and a cable portion for conductive connection by the conductive layer of the base substrate.
The insulating film of the laminated plate for multilayering extends to the cable portion of the base substrate, and the insulating film forms a cover film that covers the conductor layer of the cable portion. Printed wiring board.   The printed wiring board according to claim 1, wherein the insulating film of the laminated board is bonded to the surface on the conductor layer side of the base substrate with an adhesive layer.   The printed wiring board according to claim 1 or 2, wherein both the base film of the base substrate and the insulating film of the laminated plate are made of a flexible resin film.   The printed wiring board according to claim 3, wherein a prepreg is laminated on the multilayer portion. A laminated board having a conductor layer on at least one side of the insulating film is pasted on the surface of the base substrate having the conductor layer on at least one side of the insulating base film in order to make the partial area multilayer. In addition, a multilayer curing step is performed in which a multilayer portion is formed by the conductor layer of the base substrate and the conductor layer of the laminate, and the other portion is a cable portion for conducting connection by the conductor layer of the base substrate. Have
The insulating film of the laminated plate extends to the cable portion of the base substrate, the insulating film is bonded to the cable portion in the laminated curing step, and the cable portion is bonded to the cable portion by the insulating film. A method of manufacturing a printed wiring board having a structure in which the conductor layer is covered with a protective coating.

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