Method for manufacturing a printed wiring board

Abstract

According to the present invention, when a printed wiring board is produced by a semi-additive method, a used remover liquid after usage for removal of a nickel / chromium-containing layer (5) is regenerated by being brought into contact with a chelating resin that has a functional group represented by formula (1).　In formula (1), a plurality of R moieties represent a same divalent hydrocarbon group having from 1 to 5 carbon atoms; and some of the hydrogen atoms may be substituted by halogen atoms.

Description

Technical Field

[0001] The present disclosure relates to a method for manufacturing a printed wiring board.

[0002] This application claims priority based on Japanese Application No. 2020-194324 filed on November 24, 2020, and incorporates by reference all the descriptions described in the above Japanese application.

Background Art

[0003] With the miniaturization and weight reduction of electronic devices, the miniaturization of the wiring portion of printed wiring boards has been attempted. As a method for miniaturizing the wiring portion of a printed wiring board, for example, a seed layer is formed on the surface of an insulating resin layer, and after coating portions other than the portions where circuits are to be formed with a plating resist, a copper plating layer is selectively formed only on the circuit portions by electroplating. Further, after removing the plating resist, the printed wiring board is formed by removing the seed layer other than the circuit portions (see Japanese Patent Application Laid-Open No. 2004-6773).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

[0005] The manufacturing method of the printed wiring board of the present disclosure is a manufacturing method of a printed wiring board including a conductive pattern including a plurality of wiring portions, the method including: a step of preparing an insulating base film on which a nickel-chromium-containing layer is directly or indirectly laminated; a step of laminating a resist pattern directly or indirectly on the surface of the nickel-chromium-containing layer after the step of preparing the base film; a step of laminating a copper plating layer by plating on a region of the surface side of the nickel-chromium-containing layer where the resist pattern is not laminated after the step of laminating the resist pattern; a step of removing the resist pattern after the step of laminating the copper plating layer; a step of removing the nickel-chromium-containing layer in a region of the nickel-chromium-containing layer where the copper plating layer is not laminated using a removal liquid after the step of removing the resist pattern; and a step of regenerating the used removal liquid obtained in the step of removing the nickel-chromium-containing layer by bringing the used removal liquid into contact with a chelating resin, wherein the chelating resin has a functional group represented by the following formula (1).

[0006] [Chemical formula] (In formula (1), a plurality of Rs are the same divalent hydrocarbon groups having 1 to 5 carbon atoms. A part of the hydrogen atoms of the hydrocarbon group may be substituted with halogen atoms.)

[0007] Another method for manufacturing a printed wiring board according to the present disclosure is a method for manufacturing a printed wiring board including a conductive pattern including a plurality of wiring portions, the method including: preparing an insulating base film having a nickel-chromium-containing layer directly or indirectly laminated on a surface thereof; after the step of preparing the base film, directly or indirectly laminating a resist pattern on the surface of the nickel-chromium-containing layer; after the step of laminating the resist pattern, laminating a copper plating layer by plating on a region of the surface side of the nickel-chromium-containing layer where the resist pattern is not laminated; after the step of laminating the copper plating layer, removing the resist pattern; after the step of removing the resist pattern, removing the nickel-chromium-containing layer in a region of the nickel-chromium-containing layer where the copper plating layer is not laminated using a regenerated removal liquid, the regenerated removal liquid being regenerated by bringing a used removal liquid into contact with a chelating resin, and the chelating resin being a functional group represented by the following formula (1).

[0008] [Chemical formula] (In formula (1), a plurality of Rs are the same divalent hydrocarbon group having 1 to 5 carbon atoms. A part of the hydrogen atoms of the hydrocarbon group may be substituted with halogen atoms.)

[0009] In the present disclosure, the "insulating base film having a nickel-chromium-containing layer directly laminated on the surface" refers to an insulating base film having a nickel-chromium-containing layer laminated directly above the surface. The "insulating base film having a nickel-chromium-containing layer indirectly laminated on the surface" refers to an insulating base film having a nickel-chromium-containing layer laminated directly above the surface via one or more other layers such as a conductive layer. "Directly laminating a resist pattern on the surface of the nickel-chromium-containing layer" means laminating a resist pattern directly above the nickel-chromium-containing layer. "Indirectly laminating a resist pattern on the surface of the nickel-chromium-containing layer" means laminating a resist pattern layer directly above the nickel-chromium-containing layer via one or more other layers such as a conductive layer.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Embodiments for Carrying Out the Invention

[0011] [Problems to be Solved by the Invention] For example, in the manufacture of a printed wiring board, a seed layer is formed on a substrate, and a copper plating layer or the like is laminated thereon. As the seed layer, there is a layer containing, for example, nickel and chromium. Such a seed layer is partially removed during the manufacturing process, and generally, a nickel-chromium-containing layer removing solution is used for the removal. The nickel-chromium-containing layer removing solution is a solution for removing the nickel-chromium-containing layer. Hereinafter, it may be simply referred to as a removing solution. Such a removing solution cannot be reused repeatedly. The reason is that when the seed layer is immersed in the removing solution, metal components of other layers of the printed wiring board dissolve into the removing solution, increasing the metal concentration in the removing solution, and as a result, the etching performance deteriorates.

[0012] In particular, in a fine printed wiring board, a decrease in etching performance causes peeling of the wiring portion, which consequently affects the performance of the circuit board.

[0013] The present disclosure has been made based on such circumstances, and an object thereof is to provide a method for manufacturing a printed wiring board capable of extending the life of a stripping solution and suppressing peeling of a wiring portion using a regenerated stripping solution obtained by regenerating the stripping solution.

[0014] [Effects of the Present Disclosure] According to the present disclosure, it is possible to reuse a used stripping solution and extend the life of the stripping solution.

[0015] [Description of Embodiments of the Present Disclosure] First, embodiments of the present disclosure will be listed and described.

[0016] The method for manufacturing a printed wiring board of the present disclosure is a method for manufacturing a printed wiring board including a conductive pattern including a plurality of wiring portions, the method including: preparing an insulating base film having a nickel-chromium-containing layer laminated directly or indirectly on a surface; after the step of preparing the base film, laminating a resist pattern directly or indirectly on the surface of the nickel-chromium-containing layer; after the step of laminating the resist pattern, laminating a copper plating layer by plating on a region of the surface side of the nickel-chromium-containing layer where the resist pattern is not laminated; after the step of laminating the copper plating layer, removing the resist pattern; after the step of removing the resist pattern, removing the nickel-chromium-containing layer of a region of the nickel-chromium-containing layer where the copper plating layer is not laminated using a stripping solution; and regenerating the used stripping solution obtained in the step of removing the nickel-chromium-containing layer by bringing the used stripping solution into contact with a chelating resin, wherein the chelating resin has a functional group represented by the following formula (1).

[0017] [Chemical Formula] (In formula (1), a plurality of Rs are the same divalent hydrocarbon group having 1 to 5 carbon atoms. A part of the hydrogen atoms of the hydrocarbon group may be substituted with a halogen atom.)

[0018] The stripping solution used for removing the nickel-chromium-containing layer generally contains hydrochloric acid, sulfuric acid, etc. In such a stripping solution, in addition to nickel and chromium, a little copper contained in the wiring portion is also dissolved. When the concentration of copper ions in the solution increases, the dissolution rate of copper further increases. Therefore, the life of the stripping solution is determined by the concentration of copper ions in the stripping solution. The inventors of the present invention considered that it is necessary to keep the concentration of copper ions in the stripping solution low in order to extend the life of the stripping solution and suppress peeling of the manufactured circuit, and conducted intensive studies. As a result, it was found that by bringing the stripping solution into contact with a chelating resin having a functional group represented by the above formula (1), copper ions in the stripping solution can be adsorbed onto the chelating resin. The method for manufacturing the printed wiring board includes a step of regenerating the used stripping solution by bringing the used stripping solution into contact with a chelating resin having a functional group represented by the above formula (1) after the step of removing the nickel-chromium-containing layer. Since the concentration of copper ions in the stripping solution obtained by regeneration is reduced, it can be reused as a regenerated stripping solution, and the life of the stripping solution can be extended.

[0019] It is preferable to further include a step of laminating a conductive layer on the surface of the nickel-chromium-containing layer after the step of preparing the base film and before the step of laminating the resist pattern, and a step of removing the conductive layer after the step of removing the resist pattern and before the step of removing the nickel-chromium-containing layer. By laminating a conductive layer on the surface of the nickel-chromium-containing layer, a sufficient current can flow as a cathode in the step of laminating a copper plating layer, which is a subsequent step.

[0020] It is preferable that the regenerated removal liquid obtained in the step of regenerating the used removal liquid contains chloride ions and copper ions, has a pH of 1 or less, and the concentration of the copper ions is 1 ppm or more and 2000 ppm or less. According to this form, the removal effects of nickel and chromium can be maintained well. Further, since the regenerated removal liquid is strongly acidic with a pH of 1 or less, the removal effect of the nickel-chromium-containing layer can be further improved. Furthermore, since the concentration of copper ions in the regenerated removal liquid is within the above range, while the removal effect of the nickel-chromium-containing layer is made good, the concentration of copper ions in the regenerated removal liquid can be kept low, and the suppression effect on the peeling of the wiring part and the suppression effect on the short circuit due to the collapse of the wiring part can be enhanced.

[0021] In the manufacturing method of the printed wiring board of the present disclosure, it is preferable that the regenerated removal liquid obtained in the step of regenerating the used removal liquid further contains a pyridine-based compound and the concentration of the pyridine-based compound is more than 0 ppm and 5000 ppm or less. According to this form, the removal effects of nickel and chromium can be maintained well. Further, in the removal liquid, a part of the chelating resin having the functional group represented by the above formula (1) is decomposed to generate a pyridine-based compound as an impurity. The inventors have found that this impurity inhibits the removal of the nickel-chromium-containing layer. By setting the concentration of the pyridine-based compound in the regenerated removal liquid to 5000 ppm or less, the inhibitory action on the removal of nickel and chromium by the pyridine-based compound can be reduced, so that the removal effects of nickel and chromium can be maintained well.

[0022] According to the present disclosure, it is preferable that the functional group is a bis(2-pyridylmethyl)amino group. Since the chelating resin has the functional group represented by the above formula (1), the removal effect of the nickel-chromium-containing layer can be further improved.

[0023] Also, another method for manufacturing a printed wiring board according to the present disclosure is a method for manufacturing a printed wiring board including a conductive pattern including a plurality of wiring portions, the method including: preparing an insulating base film having a nickel-chromium-containing layer laminated directly or indirectly on a surface thereof; after the step of preparing the base film, directly or indirectly laminating a resist pattern on a surface of the nickel-chromium-containing layer; after the step of laminating the resist pattern, laminating a copper plating layer by plating on a region of the surface side of the nickel-chromium-containing layer where the resist pattern is not laminated; after the step of laminating the copper plating layer, removing the resist pattern; after the step of removing the resist pattern, removing the nickel-chromium-containing layer in a region of the nickel-chromium-containing layer where the copper plating layer is not laminated using a regenerated removal liquid, the regenerated removal liquid being regenerated by bringing a used removal liquid into contact with a chelating resin, and the chelating resin being a functional group represented by the following formula (1).

[0024] [Chemical Formula] (In formula (1), a plurality of Rs are the same divalent hydrocarbon group having 1 to 5 carbon atoms. A part of hydrogen atoms of the hydrocarbon group may be substituted with halogen atoms.)

[0025] The method for manufacturing the printed wiring board includes a step of removing the nickel-chromium-containing layer in a region where the copper plating layer is not laminated in the nickel-chromium-containing layer using a regenerated removal liquid, thereby aiming at reusing the used removal liquid. Further, in the method for manufacturing the printed wiring board, since the regenerated removal liquid is regenerated by bringing the used removal liquid into contact with a chelating resin, copper ions in the used removal liquid are adsorbed by the chelating resin. As a result, since the concentration of copper ions in the regenerated removal liquid is reduced, while improving the removal effect of the nickel-chromium-containing layer, the progress of dissolution of copper contained in the wiring portion in the step of removing the nickel-chromium-containing layer can be suppressed. As a result, a printed wiring board in which peeling of the wiring portion is suppressed using the regenerated removal liquid can be manufactured. Thereby, effective utilization of the used regenerated removal liquid and reduction of manufacturing costs can be achieved.

[0026] In the present disclosure, the "surface" means the surface on the outer side in the thickness direction when viewed from the center in the thickness direction of the base film in the printed wiring board, and does not limit the vertical relationship during the manufacture or use of the printed wiring board. Further, the "used removal liquid (or used regenerated removal liquid)" in the present disclosure refers to a removal liquid in which the unused removal liquid has been used at least once in the nickel-chromium-containing layer removal step and has a concentration higher than the concentration of copper ions in the unused removal liquid. In addition, when the concentration of copper ions contained in the used regenerated removal liquid is lower than a preset concentration, it is not necessary to bring the chelating resin into contact with the used regenerated removal liquid.

[0027] [Details of Embodiments of the Present Disclosure] Hereinafter, a method for manufacturing a printed wiring board according to an embodiment of the present disclosure will be described in detail with reference to the drawings.

[0028] [Method for Manufacturing Printed Wiring Board] [First Embodiment] The manufacturing method of a printed wiring board according to the first embodiment of the present disclosure is, as shown in FIG. 1, a method for manufacturing a printed wiring board 8 including an insulating base film 1 and a conductive pattern including a plurality of wiring portions 2 formed on at least one surface side of the base film 1.

[0029] In the printed wiring board 8 manufactured by the manufacturing method of the printed wiring board, the wiring portion 2 includes a nickel-chromium-containing layer 5 laminated on the surface of the base film 1 and a copper plating layer 4 laminated on the surface of the nickel-chromium-containing layer 5 by copper plating. The manufacturing method of the printed wiring board is particularly suitable for manufacturing a fine pitch printed wiring board in which the widths of the plurality of wiring portions 2 are small and arranged at a narrow pitch. The nickel-chromium-containing layer 5 improves the adhesion between the base film 1 and the wiring portion 2, that is, the removal strength. The printed wiring board 8 can be configured to have a conductive layer 6 laminated on the surface of the nickel-chromium-containing layer 5 and formed of the same kind of metal as the copper plating layer 4, that is, copper.

[0030] FIG. 2 shows the procedure of the method for manufacturing the printed wiring board. As the method for manufacturing the printed wiring board, a semi-additive method is used. The method for manufacturing the printed wiring board includes a step of preparing an insulating base film having a nickel-chromium-containing layer laminated directly or indirectly on the surface (step S1); a step of directly or indirectly laminating a resist pattern on the surface of the nickel-chromium-containing layer after the step of preparing the base film (step S3); a step of laminating a copper plating layer by plating on a region of the surface side of the nickel-chromium-containing layer where the resist pattern is not laminated after the step of laminating the resist pattern (step S4); a step of removing the resist pattern after the step of laminating the copper plating layer (step S5); a step of removing the nickel-chromium-containing layer in a region of the nickel-chromium-containing layer where the copper plating layer is not laminated using a removal solution after the step of removing the resist pattern (step S7); and a step of regenerating the removal solution by bringing the used regenerated removal solution into contact with a chelating resin after the step of removing the nickel-chromium-containing layer (step S8). The method for manufacturing the printed wiring board preferably further includes a step of directly or indirectly laminating a conductive layer on the surface of the nickel-chromium-containing layer (step S2) after the step of preparing the base film (step S1). Further, when the conductive layer is formed, it is preferable to have a step of removing the conductive layer (step S6) after the step of removing the resist pattern (step S5).

[0031] [Step of preparing the base film] In the step of preparing the base film in step S1, a base film having a nickel-chromium-containing layer laminated thereon is prepared. The base film has insulation properties, and a nickel-chromium-containing layer 5 is laminated directly or indirectly on the surface. By including nickel and chromium in the nickel-chromium-containing layer 5, the adhesion to the base film 1 can be improved. Examples of the lamination method of the nickel-chromium-containing layer 5 include electroless plating, sputtering, vapor deposition, coupling agent coating, and the like.

[0032] (Base film) The base film 1 is mainly composed of a synthetic resin and has electrical insulation properties. The base film 1 is a base film for forming a conductive pattern. The base film 1 may have flexibility. When the base film 1 has flexibility, the printed wiring board 8 can be used as a flexible printed wiring board.

[0033] Examples of the synthetic resin include polyimide, polyethylene terephthalate, liquid crystal polymer, fluororesin, and the like.

[0034] When the printed wiring board 8 is used as a flexible printed wiring board, the lower limit of the average thickness of the base film 1 is preferably 5 μm, more preferably 10 μm. On the other hand, the upper limit of the average thickness of the base film 1 is preferably 50 μm, more preferably 40 μm. If the average thickness of the base film 1 is less than the above lower limit, the insulation strength of the base film 1 may be insufficient. On the other hand, if the average thickness of the base film 1 exceeds the above upper limit, the printed wiring board may become unnecessarily thick or the flexibility may be insufficient. The "average thickness" refers to the average value of the thicknesses measured at any five points.

[0035] In the step of preparing the base film in step S1, a base film 1 with a nickel-chromium-containing layer 5 laminated on its surface is prepared. The nickel-chromium-containing layer 5 preferably has high adhesion to the base film 1 and the conductive layer 6.

[0036] The lower limit of the average thickness of the nickel-chromium-containing layer 5 is preferably 2 nm, more preferably 4 nm. On the other hand, the upper limit of the average thickness of the nickel-chromium-containing layer 5 is preferably 30 nm, more preferably 20 nm. If the average thickness of the nickel-chromium-containing layer 5 is less than the above lower limit, sufficient adhesion may not be exhibited. On the other hand, if the average thickness of the nickel-chromium-containing layer 5 exceeds the above upper limit, the manufacturing cost may increase unnecessarily.

[0037] [Step of laminating the conductive layer] In the step of laminating the conductive layer in step S2, as shown in FIG. 3, a conductive layer 6 is laminated on the surface of the nickel-chromium-containing layer 5. With this conductive layer 6, a sufficient current can flow as a cathode in the step of laminating the copper plating layer in the subsequent step S4.

[0038] The conductive layer 6 can improve the adhesion to the copper plating layer 4, and is preferably formed of the same kind of metal as the copper plating layer 4 so that it can form the wiring of the wiring portion 2 integrally with the copper plating layer 4 in the obtained printed wiring board 8. Examples of the material of the conductive layer 6 include metals such as copper, silver, platinum, and nickel, and among them, copper with low electrical resistance and low cost is preferable.

[0039] As the lower limit of the average thickness of the conductive layer 6 to be laminated, 50 nm is preferable, and 100 nm is more preferable. On the other hand, as the upper limit of the average thickness of the conductive layer 6, 2 μm is preferable, and 1.5 μm is more preferable. When the average thickness of the conductive layer 6 is less than the above lower limit, the conductivity of the conductive layer 6 becomes insufficient, and the surface of the copper plating layer 4 laminated thereon may not be smoothed. On the other hand, when the average thickness of the conductive layer 6 exceeds the above upper limit, the erosion of the copper plating layer 4 in the step of removing the nickel-chromium-containing layer in step S6 may become unnecessarily large.

[0040] Examples of the method for laminating the conductive layer 6 include electroless plating, coating, drying, and sintering of a metal fine particle dispersion liquid in which metal fine particles are dispersed, sputtering, vapor deposition, and the like. Among them, as the method for laminating the conductive layer 6, a method by coating, drying, and sintering of a metal fine particle dispersion liquid that can laminate a conductive layer 6 having a sufficient thickness to ensure conductivity relatively easily and inexpensively is preferably adopted.

[0041] As the metal fine particle dispersion liquid, a liquid containing particles of the metal forming the conductive layer 6, a dispersion medium for the metal fine particles, and a dispersant for uniformly dispersing the metal fine particles in the dispersion medium is preferably used. By using such a metal fine particle dispersion liquid in which the metal fine particles are uniformly dispersed, the metal fine particles can be uniformly adhered to the surface of the nickel-chromium-containing layer 5, and a uniform conductive layer 6 can be laminated.

[0042] As a method of applying the metal fine particle dispersion liquid to the surface of the nickel-chromium-containing layer 5, for example, conventionally known coating methods such as spin coating method, spray coating method, bar coating method, die coating method, slit coating method, roll coating method, dip coating method, etc. can be used. Further, for example, the metal fine particle dispersion liquid may be partially applied by screen printing, dispenser, or the like.

[0043] The shorter the drying of the coating film of the metal fine particle dispersion liquid is performed, the smaller the porosity of the conductive layer 6 obtained by sintering the coating film can be. For this reason, it is preferable to promote the drying of the metal fine particle dispersion liquid by heating or blowing air, and it is more preferable to dry the coating film by blowing warm air onto the coating film of the metal fine particle dispersion liquid. The temperature of the warm air is preferably set so as not to boil the solvent of the metal fine particle dispersion liquid. As a specific temperature of the warm air, for example, it can be set to 30°C or higher and 80°C or lower.

[0044] By heating the dried coating film of the metal fine particle dispersion liquid, the dispersant and various additives in the metal fine particle dispersion liquid evaporate or thermally decompose, and the remaining metal fine particles are sintered to laminate the conductive layer 6.

[0045] The heating temperature when sintering the coating film of the metal fine particle dispersion liquid is appropriately selected depending on the material of the metal fine particles, etc., but is, for example, 150°C or higher and 500°C or lower.

[0046] [Step of laminating a resist pattern] In the step of laminating the resist pattern in step S3, after the step of preparing the base film, the resist pattern is directly or indirectly laminated on the surface of the nickel-chromium-containing layer. The resist pattern 7 has an inverted shape of the conductive pattern. In the step of laminating the resist pattern, as shown in FIG. 4, the resist pattern 7 is laminated on the surface of the conductive layer 6 by photolithography technology.

[0047] Examples of the method for laminating the resist film include a method of coating and drying a liquid resist composition, a method of thermocompression bonding a sheet-like resist composition, and the like. The sheet-like resist composition is, for example, a dry film. As such a material for the resist film, for example, those mainly composed of an acrylic resin and those commercially available as a resist material for plating can be used.

[0048] The opening of the resist pattern 7 corresponds to the width of the wiring portion 2 in the conductive pattern. The lower limit of the average width of the opening is not particularly limited, but 5 μm is preferable, and 6 μm is more preferable. On the other hand, the upper limit of the average width of the opening is preferably 20 μm, and more preferably 15 μm. When the average width of the opening of the resist pattern 7 is within the above range, the effect of the manufacturing method of the printed wiring board as a fine pitch circuit can be more exerted.

[0049] [Step of laminating a copper plating layer] In the step of laminating the copper plating layer in step S4, after the step of laminating the resist pattern, a copper plating layer 4 is laminated by plating on the region of the surface side of the nickel-chromium-containing layer 5 where the resist pattern 7 is not laminated. When the conductive layer 6 is laminated in step S2, the copper plating layer 4 is laminated on the region of the surface of the conductive layer 6 where the resist pattern 7 is not laminated. In the step of laminating the copper plating layer 4, electroplating is performed using the nickel-chromium-containing layer 5 and the conductive layer 6 as cathodes, and as shown in FIG. 5, the copper plating layer 4 is laminated on the surface of the conductive layer 6 exposed from the resist pattern. The region of the surface of the conductive layer 6 exposed from the resist pattern corresponds to the opening of the resist pattern 7.

[0050] The metal laminated by plating is copper. Copper has a low electrical resistance and is inexpensive, and can be integrated with the conductive layer 6 by using the same kind of metal as the metal forming the conductive layer 6.

[0051] The plating solution used in the step of laminating the copper plating layer is not particularly limited, and for example, a known copper plating solution containing copper sulfate, copper pyrophosphate, etc. can be used.

[0052] The line and space L / S in the above conductive pattern is preferably 5 μm / 5 μm or more and 20 μm / 20 μm or less. The method for manufacturing the printed wiring board can obtain a fine printed wiring board capable of suppressing peeling and short-circuiting of the wiring portion even when manufacturing a printed wiring board having a fine pitch circuit such as a line and space of L / S = 10 / 10 or less. Therefore, the method for manufacturing the printed wiring board can exhibit a more excellent suppression effect on peeling and short-circuiting of the wiring portion as a fine pitch circuit when the line and space L / S in the above conductive pattern is within the above range. Here, "line and space" represents the width [μm] of the wiring portion and the size of the gap [μm] between the wiring portions in the conductive pattern.

[0053] [Step of removing the resist pattern] In the step of removing the resist pattern in step S5, after the step of laminating the copper plating layer, the resist pattern 7 is removed. In the step of removing the resist pattern, as shown in FIG. 6, the resist pattern 7 is dissolved and removed using a resist removing solution.

[0054] As the resist removing solution, a solution that dissolves the resist pattern 7 but does not dissolve the base film 1, the nickel-chromium-containing layer 5, the conductive layer 6, and the copper plating layer 4 is used. As such a resist removing solution, for example, a known removing solution mainly composed of 2-aminoethanol, tetramethylammonium hydroxide, an organic acid, etc. can be used.

[0055] [Step of removing the conductive layer] In the step of removing the conductive layer in Step S6, the exposed conductive layer 6 is dissolved and removed by a removal liquid. In the step of removing the conductive layer in Step S6, as shown in FIG. 7, the region where the conductive layer 6 is exposed is removed.

[0056] As the conductive layer removal liquid used in this step of removing the conductive layer, for example, an aqueous sulfuric acid-hydrogen peroxide solution can be used. The aqueous sulfuric acid-hydrogen peroxide solution is sometimes called a piranha solution.

[0057] [Step of removing the nickel-chromium-containing layer] In the step of removing the nickel-chromium-containing layer in Step S7, after the step of removing the conductive layer, a removal liquid is used to remove the nickel-chromium-containing layer in the region where the copper plating layer 4 is not laminated in the nickel-chromium-containing layer 5, that is, the exposed nickel-chromium-containing layer 5. In this step, a removal liquid that etches nickel and chromium is used to dissolve and remove the nickel-chromium-containing layer 5. As a method of dissolution, for example, it can be performed by storing the removal liquid in a liquid tank and immersing the substrate in the removal liquid. As the removal liquid, an unused removal liquid may be used, or a regenerated removal liquid described later may be used. However, the form of using the regenerated removal liquid will be described in the second embodiment. In this way, a conductive pattern including a plurality of wiring portions is manufactured by removing the region of the nickel-chromium-containing layer 5 that overlapped with the resist pattern 7 in a plan view. The wiring portion 2 after the step of removing the nickel-chromium-containing layer is as shown in FIG. 1.

[0058] [Step of regenerating the removal liquid] In the step of regenerating the removal liquid in Step S8, after the step of removing the nickel-chromium-containing layer, the used regenerated removal liquid is brought into contact with a chelating resin to regenerate the used regenerated removal liquid. Specifically, in the step of regenerating the removal liquid, after the step of removing the nickel-chromium-containing layer, the used removal liquid is recovered, and the recovered removal liquid is brought into contact with a chelating resin.

[0059] The chelating resin has a functional group represented by the following formula (1). By bringing the removal liquid into contact with this chelating resin, copper ions in the removal liquid can be adsorbed, so that the obtained regenerated removal liquid can maintain a low copper ion concentration. Thereby, while extending the life of the removal liquid and improving the removal effect of the nickel-chromium-containing layer, the progress of dissolution of copper contained in the wiring portion in the step of removing the nickel-chromium-containing layer can be suppressed. Also, even when manufacturing a fine printed wiring board, peeling of the wiring portion can be suppressed.

[0060]

Chemical formula

[0061] In the above formula (1), a plurality of Rs are the same divalent hydrocarbon group having 1 to 5 carbon atoms. A part of the hydrogen atoms of the hydrocarbon group may be substituted with a halogen atom.

[0062] Examples of the divalent hydrocarbon group having 1 to 5 carbon atoms represented by the above R include a divalent chain hydrocarbon group having 1 to 5 carbon atoms and a divalent alicyclic hydrocarbon group having 3 to 5 carbon atoms. Further, the chain hydrocarbon group may be either linear or branched.

[0063] Examples of the divalent chain hydrocarbon group include a divalent chain saturated hydrocarbon group and a divalent chain unsaturated hydrocarbon group.

[0064] Examples of the divalent chain saturated hydrocarbon group include a methanediyl group (-CH2-), an ethanediyl group (-C2H4-), a propanediyl group (-C3H6-), a butanediyl group (-C4H8-), a dimethylethanediyl group (-C4H8-), a dimethylmethanediyl group (-C3H6-), a methylethanediyl group (-C5H 10 -), etc.

[0065] Examples of the divalent chain unsaturated hydrocarbon group include an ethenediyl group (-C2H2-), a propenediyl group (-C3H4-), a butenediyl group (-C4H6-), a methylenemethanediyl group (-C2H4-), a methyleneethanediyl group (-C3H4-), a methylenepropanediyl group (-C4H6-), an ethylideneethanediyl group (-C4H6-), an ethynediyl group (-C2H2-), a propynediyl group (-C3H2-), a butynediyl group (-C4H4-), a vinylethynyl group (-C4H2-), an ethynylpropenediyl group (-C5H4-), a pentadiindiyl group (-C5H2-), and the like.

[0066] Examples of the divalent alicyclic hydrocarbon group include a divalent alicyclic saturated hydrocarbon group and a divalent alicyclic unsaturated hydrocarbon group.

[0067] Examples of the divalent alicyclic saturated hydrocarbon group include a cyclopropanediyl group (-C3H4-), a cyclobutanediyl group (-C4H6-), a cyclopentanediyl group (-C5H8-), and the like.

[0068] Examples of the divalent alicyclic unsaturated hydrocarbon group include a cyclopentenediyl group (-C5H6-), and the like.

[0069] Examples of the halogen atom in which a part of the hydrogen atoms of the hydrocarbon group may be substituted include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

[0070] The functional group is preferably a bis(2-pyridylmethyl)amino group. By having the functional group represented by the above formula (1), the chelating resin can further improve the removal effect of the nickel-chromium-containing layer.

[0071] As the base material of the chelating resin, for example, polystyrene, styrene-divinylbenzene copolymer, etc. can be used. As described above, the removal liquid is used in the step of removing the nickel-chromium-containing layer, so that copper dissolves from the laminated copper plating layer or the like, and the concentration of copper ions in the removal liquid increases. By using the chelating resin in the step of regenerating the used regeneration removal liquid, the effect of reducing copper ions in the used regeneration removal liquid is excellent.

[0072] As a method of bringing the chelating resin into contact with the used regeneration removal liquid, for example, a method using a known chelating resin column can be adopted, and the chelating resin is filled in the chelating resin column. Then, the used regeneration removal liquid is flowed into the chelating resin column to remove copper ions from the used regeneration removal liquid. Further, as a method of bringing the chelating resin into contact with the used regeneration removal liquid, without using a chelating resin column, the chelating resin can be directly added to the used regeneration removal liquid, and after a predetermined time has elapsed, the chelating resin can be removed by filtration for regeneration treatment. Among these methods of bringing the chelating resin into contact with the used regeneration removal liquid, a method using a chelating resin column in which the used regeneration removal liquid and the chelating resin can efficiently contact and copper ions can be removed in a short time is preferable.

[0073] Since the amount of copper ions that the chelating resin can adsorb is determined, the copper ion concentration in the regeneration removal liquid can be adjusted by the ratio of the amounts of the used regeneration removal liquid and the chelating resin. As the amount of the chelating resin used, it is preferably 50 L or more and 200 L or less with respect to 200 L of the used regeneration removal liquid.

[0074] The regenerated stripping solution can be used as a stripping solution for removing the nickel-chromium-containing layer from a substrate having a nickel-chromium-containing layer and a copper-containing layer. The regenerated stripping solution may be returned to the step of removing the nickel-chromium-containing layer in the previous step. In this case, for the same substrate, the stripping step and the regeneration step may be alternately repeated, and the regenerated stripping solution may be circulated. Alternatively, the regenerated stripping solution can be used in the step of removing the nickel-chromium-containing layer of another printed wiring board that can be subsequently performed. Further, the above regenerated stripping solution may be used by mixing with an unused stripping solution or a used stripping solution.

[0075] Next, the regenerated stripping solution will be described.

[0076] As described above, the "used regenerated stripping solution" refers to a stripping solution that has been used at least once in the nickel-chromium-containing layer removal step and has a concentration higher than the concentration of copper ions in the unused stripping solution. As this unused stripping solution, it preferably contains chloride ions and has a pH of 1 or less. By removing the nickel-chromium-containing layer under the strongly acidic condition where the pH of the stripping solution is 1 or less, the removal effect of the nickel-chromium-containing layer can be further improved. Since the passive film of the nickel-chromium-containing layer can be removed, hydrochloric acid is preferred among strong acids. As the unused stripping solution, a hydrochloric acid aqueous solution having a concentration of 5% by mass or more and 20% by mass or less is preferred.

[0077] The above regenerated stripping solution is preferably a hydrochloric acid aqueous solution having a concentration of 5% by mass or more and 20% by mass or less.

[0078] From the viewpoint of maintaining a good removal effect of the nickel-chromium-containing layer, the regenerated stripping solution preferably contains chloride ions and copper ions, has a pH of 1 or less, and the concentration of the above copper ions is 1 ppm or more and 2000 ppm or less. Since the regenerated stripping solution has a strong acidity with a pH of 1 or less, the removal effect of the nickel-chromium-containing layer can be further improved. Further, since the concentration of copper ions in the regenerated stripping solution is within the above range, while improving the removal effect of the nickel-chromium-containing layer, the concentration of copper ions in the regenerated stripping solution can be maintained low, and the suppression effect on the peeling of the wiring portion and the suppression effect on the short circuit due to the collapse of the wiring portion can be enhanced.

[0079] Note that, before the step of regenerating the removal liquid, a step of measuring the copper ion concentration in the used regenerated removal liquid may be arbitrarily added. As a result of the measurement, if the copper ion concentration is equal to or lower than the above upper limit, the used regenerated removal liquid can be used as it is, and it is not always necessary to carry out the next step of regenerating the removal liquid.

[0080] Further, it is preferable that the regenerated removal liquid further contains a pyridine-based compound and the concentration of the pyridine-based compound is more than 0 ppm and 5000 ppm or less. According to this form, the removal effects of nickel and chromium can be maintained well. Furthermore, by setting the concentration of the pyridine-based compound in the regenerated removal liquid to 5000 ppm or less, the inhibitory action on the removal of nickel and chromium by the pyridine-based compound can be reduced, so that the removal effects of nickel and chromium can be maintained well.

[0081] When the line and space L / S in the conductive pattern is 5 μm / 5 μm or more and less than 10 μm / 10 μm, the concentration of copper ions in the regenerated removal liquid is more preferably 30 ppm or more and 1000 ppm or less. When the line and space L / S is 10 μm / 10 μm or more and less than 15 μm / 15 μm, the concentration of copper ions in the regenerated removal liquid is more preferably 30 ppm or more and 1500 ppm or less. Furthermore, when the line and space L / S is 15 μm / 15 μm or more and 20 μm / 20 μm or less, the concentration of copper ions in the regenerated removal liquid is more preferably 30 ppm or more and 2000 ppm or less.

[0082] The relationship between the copper ion concentration in the regenerated removal liquid and the above line and space L / S is the same for any of the removal liquids.

[0083] When the chelating resin has a functional group represented by the above formula (1), a trace amount of a pyridine-based compound derived from the functional group may be generated in the regeneration removal liquid. The pyridine-based compound is a compound resulting from the decomposition of the chelating resin having the functional group represented by the above formula (1). The concentration of the pyridine-based compound in the regeneration removal liquid is preferably 0 ppm or more than 0 ppm and 5000 ppm or less. As described above, the presence of the pyridine-based compound in the regeneration removal liquid inhibits the removal of nickel and chromium. Therefore, by setting the concentration of the pyridine-based compound within the above range, the inhibitory effect on the removal of nickel and chromium by the pyridine-based compound can be reduced, so that the removal effect of nickel and chromium can be maintained well. Further, when the line and space L / S in the conductive pattern is 5 μm / 5 μm or more and less than 10 μm / 10 μm, the concentration of the pyridine-based compound in the regeneration removal liquid is more preferably 10 ppm or more and 3000 ppm or less. When the line and space L / S is 10 μm / 10 μm or more and less than 15 μm / 15 μm, the concentration of the pyridine-based compound in the regeneration removal liquid is more preferably 10 ppm or more and 4000 ppm or less. Furthermore, when the line and space L / S is 15 μm / 15 μm or more and 20 μm / 20 μm or less, the concentration of the pyridine-based compound in the regeneration removal liquid is more preferably 10 ppm or more and 5000 ppm or less.

[0084] The concentration of the pyridine-based compound in the regeneration removal liquid with respect to the above line and space L / S has the same relationship in any of the removal liquids.

[0085] According to the method for manufacturing a printed wiring board of the first embodiment, after the step of removing the nickel-chromium-containing layer, the used regeneration removal liquid is brought into contact with a chelating resin having a functional group represented by the above formula (1) to regenerate the used regeneration removal liquid. Since the concentration of copper ions in the regeneration removal liquid is reduced, it can be reused as a regeneration removal liquid, and the life of the removal liquid can be extended.

[0086] [Second Embodiment] The manufacturing method of a printed wiring board according to the second embodiment of the present disclosure is a method for manufacturing a printed wiring board including a conductive pattern having a plurality of wiring portions, the method comprising: preparing an insulating base film having a nickel-chromium-containing layer directly or indirectly laminated on a surface thereof; after the step of preparing the base film, directly or indirectly laminating a resist pattern on the surface of the nickel-chromium-containing layer; after the step of laminating the resist pattern, laminating a copper plating layer by plating on a region of the surface side of the nickel-chromium-containing layer where the resist pattern is not laminated; after the step of laminating the copper plating layer, removing the resist pattern; after the step of removing the resist pattern, removing the nickel-chromium-containing layer in a region of the nickel-chromium-containing layer where the copper plating layer is not laminated using a regenerated removal liquid, wherein the regenerated removal liquid is regenerated by bringing a used removal liquid into contact with a chelating resin, and the chelating resin is a functional group represented by the following formula (1). That is, the manufacturing method of a printed wiring board according to the second embodiment is different from the manufacturing method of a printed wiring board according to the first embodiment in that, in the step of removing the nickel-chromium-containing layer, the nickel-chromium-containing layer is removed using a regenerated removal liquid. Note that the regenerated removal liquid in the second embodiment is as described above.

[0087] The manufacturing method of a printed wiring board according to the second embodiment of the present disclosure includes a step of removing the nickel-chromium-containing layer in a region of the nickel-chromium-containing layer where the copper plating layer is not laminated using a regenerated removal liquid, thereby achieving reuse of a used removal liquid. Further, in the manufacturing method of the printed wiring board, since the regenerated removal liquid is regenerated by bringing a used removal liquid into contact with a chelating resin, copper ions in the used removal liquid are adsorbed by the chelating resin. As a result, since the concentration of copper ions in the regenerated removal liquid is reduced, while improving the removal effect of the nickel-chromium-containing layer, progress of dissolution of copper contained in the wiring portion in the step of removing the nickel-chromium-containing layer can be suppressed. As a result, it is possible to manufacture a printed wiring board in which peeling of the wiring portion is suppressed using the regenerated removal liquid. Thereby, effective utilization of the used regenerated removal liquid and reduction of manufacturing costs can be achieved.

[0088] [Other Embodiments] The embodiments disclosed this time should be considered as illustrative in all respects and not restrictive. The scope of the present disclosure is not limited to the configurations of the above embodiments, but is indicated by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims.

[0089] In the above embodiment, the unused stripping solution or the regenerated stripping solution is used as the stripping solution, but the unused stripping solution, the regenerated stripping solution, and the used regenerated stripping solution may be used in any combination.

Examples

[0090] Hereinafter, the present disclosure will be described in more detail by way of examples, but the present disclosure is not limited to these examples.

[0091] [No.1~No.14] A base film made of a polyimide film with an average thickness of 25 μm was prepared. A conductive pattern including 500 wiring portions arranged in parallel was formed on both sides of this base film by a semi-additive method. Specifically, first, a nickel-chromium-containing layer with an average thickness of 4 nm made of nickel and chromium was laminated (step of preparing the base film). Next, a conductive layer with an average thickness of 0.2 μm made of copper was laminated (step of laminating the conductive layer).

[0092] Next, a photoresist film was laminated on substantially the entire surface of the conductive layer by thermocompression bonding of an acrylic dry film resist. Next, by selectively exposing the photoresist film using a photomask, a portion of the photoresist film that dissolves in the developer and a portion that does not dissolve were formed. Next, by washing away the dissolving portion using the developer, a resist pattern having openings corresponding to the formation regions of the plurality of wiring portions was laminated. The steps from the process of laminating the photoresist film to the process of washing away the dissolving portion correspond to the process of laminating the resist pattern.

[0093] Next, an electrolytic copper plating was performed on the surface of the conductive layer after the step of laminating the resist pattern using a copper sulfate plating bath at 25 °C containing 90 g / L of copper sulfate pentahydrate, thereby laminating a copper plating layer with an average thickness of 10 μm (step of laminating the copper plating layer).

[0094] Next, after the step of laminating the copper plating layer, the resist pattern was removed using a resist stripping solution (step of removing the resist pattern). Then, using a conductive layer stripping solution, the conductive layer in the region of the conductive layer where the copper plating layer was not laminated was removed (step of removing the conductive layer).

[0095] Next, the exposed nickel-chromium-containing layer was removed (step of removing the nickel-chromium-containing layer). In this step of removing the nickel-chromium-containing layer, the nickel-chromium-containing layer was removed using an unused stripping solution. The composition of the unused stripping solution was 15% hydrochloric acid, 10% sulfuric acid, a copper ion concentration of 50 ppm, and a pH of 1 or less. In the step of removing the nickel-chromium-containing layer, the substrate was immersed in the unused stripping solution at a liquid temperature of 45 °C. The treatment time for removing the nickel-chromium-containing layer was set to 30 seconds.

[0096] Next, in the step of regenerating the stripping solution, a chelating resin column was filled with 50 L of resin, and the used stripping solution was passed through at 10 L / min to remove copper ions. As the chelating resin, three types of chelating resins each having a bis(2-pyridylmethyl)amino group, an imidodiacetic acid group, and an aminophosphonic acid group were used. Also, the pH of all the regenerated stripping solutions was set to 1 or less.

[0097] The concentration of copper ions in the regenerated stripping solution was determined by quantifying the concentration of copper ions in the sample solution using an inductively coupled plasma (ICP) optical emission spectrometer.

[0098] The concentration of the pyridine-based compound in the regenerated removal liquid was quantified as follows. The sample liquid was diluted with water using a UV-visible spectrophotometer UV-1800 manufactured by Shimadzu Corporation, and the absorbance at 263 nm was measured. From the calibration curve of bis(2-pyridylmethyl)amine prepared in advance, the concentration of the pyridine-based compound in the regenerated removal liquid was converted and quantified.

[0099] By adjusting the copper ion concentration of the used removal liquid and the number of times of liquid passing through the chelating resin column for chelating resin, etc., the copper ion concentration and the pyridine-based compound concentration of the regenerated removal liquid were changed. The copper ion concentration and the pyridine-based compound concentration of the obtained regenerated removal liquid are shown in Table 1 (from No.2 to No.14).

[0100] Next, the removal effect of the nickel-chromium-containing layer was measured using the unused removal liquid (No.1) and the regenerated removal liquid (Sample No.2 to No.14).

[0101] First, printed wiring boards having different line and space (L / S) [μm / μm] were produced (No.1 to No.14). As the production method, the same steps as the method for obtaining the regenerated removal liquid in the above-described embodiment were adopted. However, in order to change the line and space, the size of the opening of the resist pattern was adjusted.

[0102] For No.1 to No.14 obtained by performing up to the step of removing the above conductive layer, a step of removing the nickel-chromium-containing layer was performed using the unused removal liquid (No.1) and the regenerated removal liquid (No.2 to No.14). Note that only the regenerated removal liquid was used for the regenerated removal liquid without mixing it with the unused removal liquid or the used removal liquid. The step of removing the nickel-chromium-containing layer was performed in the same manner as the step of removing the nickel-chromium-containing layer described above, except that the unused removal liquid (No.1) and the regenerated removal liquid (No.2 to No.14) were used.

[0103] For the printed wiring boards of Sample No.1 to No.14 obtained after the step of removing the nickel-chromium-containing layer, the peeling occurrence rate of the wiring part and the short-circuit occurrence rate due to the residue of the nickel-chromium-containing layer were evaluated.

[0104] [Evaluation] (Occurrence rate of peeling of wiring part) Regarding printed wiring boards No.1 to No.14, the occurrence rate [%] of peeling of the wiring part was determined by detecting the number of occurrences of peeling through visual inspection.

[0105] (Short-circuit occurrence rate due to nickel-chromium-containing layer residue) Regarding printed wiring boards No.1 to No.14, the short-circuit occurrence rate [%] due to nickel-chromium-containing layer residue was determined by detecting the number of short circuits through electrical inspection.

[0106] Table 1 shows the evaluation results of the occurrence rate of peeling of the wiring part and the short-circuit occurrence rate due to nickel-chromium-containing layer residue.

[0107]

Table 1

[0108] As shown in Table 1, for No.2 to No.12 that used the regenerated removal liquid regenerated by the chelating resin having a bis(2-pyridylmethyl)amino group in the step of removing the nickel-chromium-containing layer, the occurrence rate of peeling of the wiring part was low and the results were good. In particular, for No.2, No.4, No.5, No.11 and No.12, no occurrence of peeling of the wiring part and no short circuit due to nickel-chromium-containing layer residue were observed. For No.2, No.4, No.5, No.11 and No.12, the concentration of copper ions in the regenerated removal liquid was 50 ppm or more and 2000 ppm or less, and the concentration of the pyridine-based compound was 5000 ppm or less.

[0109] On the other hand, for No.13 and No.14 that used the regenerated removal liquid regenerated by the chelating resin having an imidodiacetic acid group or an aminophosphonic acid group in the step of removing the nickel-chromium-containing layer, the occurrence rate of peeling of the wiring part was high.

[0110] As described above, according to the method for manufacturing a printed wiring board of the present disclosure, the concentration of copper ions in the regeneration removal liquid can be maintained low. As a result, while improving the removal effect of the nickel-chromium-containing layer, the progress of dissolution of copper contained in the wiring portion in the step of removing the nickel-chromium-containing layer can be suppressed. Therefore, it can be seen that the life of the removal liquid can be extended, and a printed wiring board capable of suppressing peeling of the wiring portion can be obtained even when manufacturing a fine printed wiring board.

Explanation of Signs

[0111] 1 Base film 2 Wiring portion 4 Copper plating layer 5 Nickel-chromium-containing layer 6 Conductive layer 7 Resist pattern 8 Printed wiring board

Claims

1. A method for manufacturing a printed wiring board including a conductive pattern including a plurality of wiring portions, a step of preparing an insulating base film having a nickel-chromium-containing layer laminated directly or indirectly on the surface; after the step of preparing the base film, a step of laminating a resist pattern directly or indirectly on the surface of the nickel-chromium-containing layer; after the step of laminating the resist pattern, a step of laminating a copper plating layer by plating on a region of the surface side of the nickel-chromium-containing layer where the resist pattern is not laminated; after the step of laminating the copper plating layer, a step of removing the resist pattern; after the step of removing the resist pattern, a step of removing the nickel-chromium-containing layer in a region of the nickel-chromium-containing layer where the copper plating layer is not laminated using a removal liquid; a step of regenerating the used removal liquid obtained in the step of removing the nickel-chromium-containing layer by bringing the used removal liquid into contact with a chelating resin and A method for manufacturing a printed wiring board, wherein the chelating resin has a functional group represented by the following formula (1). 【Chemical formula 1】 (In formula (1), a plurality of Rs are the same divalent hydrocarbon group having 1 to 5 carbon atoms. A part of the hydrogen atoms of the hydrocarbon group may be substituted with a halogen atom.)

2. a step of laminating a conductive layer on the surface of the nickel-chromium-containing layer after the step of preparing the base film and before the step of laminating the resist pattern; a step of removing the conductive layer after the step of removing the resist pattern and before the step of removing the nickel-chromium-containing layer The method for manufacturing a printed wiring board according to claim 1, further comprising:

3. The method for manufacturing a printed wiring board according to claim 1 or claim 2, wherein the regenerated removal liquid obtained in the step of regenerating the used removal liquid contains chloride ions and copper ions, has a pH of 1 or less, and the concentration of the copper ions is 1 ppm or more and 2000 ppm or less.

4. The method for manufacturing a printed wiring board according to claim 3, wherein the regenerated removal liquid obtained in the step of regenerating the used removal liquid further contains a pyridine-based compound, and the concentration of the pyridine-based compound is more than 0 ppm and 5000 ppm or less.

5. The method for manufacturing a printed wiring board according to any one of claims 1 to 4, wherein the functional group is a bis(2-pyridylmethyl)amino group.

6. A method for manufacturing a printed wiring board including a conductive pattern including a plurality of wiring portions, preparing an insulating base film having a nickel-chromium-containing layer laminated directly or indirectly on the surface; after the step of preparing the base film, directly or indirectly laminating a resist pattern on the surface of the nickel-chromium-containing layer; after the step of laminating the resist pattern, laminating a copper plating layer by plating on a region of the surface side of the nickel-chromium-containing layer where the resist pattern is not laminated; after the step of laminating the copper plating layer, removing the resist pattern; after the step of removing the resist pattern, removing the nickel-chromium-containing layer in a region of the nickel-chromium-containing layer where the copper plating layer is not laminated using a regenerated removal liquid, wherein the regenerated removal liquid is regenerated by bringing the used removal liquid into contact with a chelating resin, A method for manufacturing a printed wiring board, wherein the chelating resin is a functional group represented by the following formula (1). 【Chemical formula 2】 (In formula (1), a plurality of Rs are the same divalent hydrocarbon group having 1 to 5 carbon atoms. A part of the hydrogen atoms of the hydrocarbon group may be substituted with a halogen atom.)

Images