WO2025079282A1 - Method for manufacturing wiring circuit board - Google Patents

Abstract

This method for manufacturing a wiring circuit board includes: a first step for supplying a waste liquid of a treatment liquid for forming a wiring circuit used in a formation step of a wiring circuit, to at least one recovery treatment from electrochemical treatment and dialysis treatment to obtain a recovery treatment liquid containing a treatment liquid component; a second step for preparing a reuse treatment liquid for forming a wiring circuit by using the recovery treatment liquid; and a third step for forming a wiring circuit by using the reuse treatment liquid for forming a wiring circuit.

Description

Method for manufacturing a printed circuit board

The present invention relates to a method for manufacturing a wired circuit board.

Wired circuit boards are manufactured by laminating conductors such as wiring and various insulating layers on a substrate. The conductors and/or insulating layers are patterned, for example, by photolithography.

In the manufacture of printed circuit boards, various processing liquids are used for cleaning metal substrates, rinsing after development when forming resist patterns, removing seed layers, etc. Since used processing liquids cannot be reused as they are, they are disposed of as waste liquids.

One way to dispose of waste liquid is to have a company take it away.

On the other hand, as a method for removing copper from a solution or liquid (particularly a used etching solution containing copper generated during printed circuit board manufacturing), a method for removing copper from a mixture containing a copper complexing agent has been proposed, which includes providing a system including an electrolytic cell including an anode and a cathode separated by a copper ion-permeable membrane; adding a liquid containing copper and a copper complexing agent to the system; and electrolytically treating the liquid (see, for example, Patent Document 1).

JP 2000-317458 A

The present invention aims to provide a method for manufacturing a wiring circuit board that can reduce the environmental impact by reusing the processing solution for wiring circuit formation used in the wiring circuit formation process.

Means for Solving the Problems The present inventors have conducted extensive research to solve the above problems, and as a result have found that the above problems can be solved, and have completed the present invention having the following gist.
That is, the present invention includes the following.

[1] A first step of subjecting a waste liquid of a wiring circuit forming treatment liquid used in a wiring circuit forming step to at least one of a recovery treatment of an electrochemical treatment and a dialysis treatment to obtain a recovered treatment liquid containing a treatment liquid component;
A second step of preparing a treatment liquid for forming a reused wiring circuit using the recovered treatment liquid;
A third step of forming a wiring circuit using the treatment liquid for forming a reused wiring circuit;
A method for manufacturing a wired circuit board, comprising:
[2] The method for producing a wired circuit board according to [1], wherein the recovery treatment is an electrodialysis treatment.
[3] The method for producing a wired circuit board according to [1] or [2], wherein the waste liquid, the recovery treatment liquid, and the treatment liquid for forming a reused wired circuit contain an acid.
[4] The method for producing a wired circuit board according to any one of [1] to [3], wherein the treatment liquid for forming a wired circuit includes at least one of an acidic cleaning liquid for cleaning a surface in a process for forming the wired circuit and an acidic etching liquid for etching in the process for forming the wired circuit.
[5] The method for producing a wired circuit board according to any one of [1] to [4], wherein the waste liquid, the recovery treatment liquid, and the treatment liquid for forming a reused wired circuit contain alcohol and water.
[6] A fourth step of subjecting the waste liquid of the treatment liquid for forming the reused wiring circuit used in the third step to at least one of a recovery treatment of an electrochemical treatment and a dialysis treatment to obtain a second recovered treatment liquid containing a treatment liquid component;
a fifth step of preparing a second reuse wiring circuit forming treatment liquid using the second recovered treatment liquid;
A sixth step of forming a wiring circuit using the second reuse wiring circuit forming treatment liquid;
The method for producing the wired circuit board according to any one of [1] to [5],
[7] The second step comprises:
A step of measuring the active ingredient in the recovered treatment liquid;
a step of adjusting the composition of the recovered treatment liquid to a predetermined composition using the measurement results of the active ingredient, thereby preparing the treatment liquid for forming a reused wiring circuit;
Including,
A method for producing a wired circuit board according to any one of [1] to [6].
[8] The method for producing a wired circuit board according to any one of [1] to [7], wherein the first step, the second step, and the third step are performed in one business establishment.

The present invention provides a method for manufacturing a wiring circuit board that can reduce the environmental impact by reusing the processing solution for wiring circuit formation used in the wiring circuit formation process.

FIG. 1 is a diagram for explaining an example of an electrodialysis treatment. FIG. 2 is a flow chart of one embodiment of a method for manufacturing a printed circuit board. FIG. 3 is a flow chart of another embodiment of the method for manufacturing a printed circuit board. FIG. 4 is a flow chart of another embodiment of the method for manufacturing a printed circuit board. FIG. 5 is a flow chart of an example of an embodiment (part 1) of a method for manufacturing a printed circuit board. FIG. 6 is a flow chart of an example of an embodiment (part 1) of the method for manufacturing a printed circuit board. FIG. 7 is a flow chart of an example of an embodiment (part 1) of the method for manufacturing a printed circuit board. FIG. 8 is a schematic diagram of an apparatus configuration for explaining one example of an embodiment (part 1) of the method for producing a wired circuit board. FIG. 9 is a schematic diagram of an apparatus configuration for explaining another example of the embodiment (part 1) of the method for producing a wired circuit board. FIG. 10 is a schematic diagram of an apparatus configuration for explaining another example of the embodiment (part 1) of the method for producing a wired circuit board. FIG. 11 is a flowchart of an example of the embodiment (part 2) of the method for producing a printed circuit board. FIG. 12 is a schematic diagram of an apparatus configuration for explaining one example of an embodiment (part 2) of the method for producing a wired circuit board. FIG. 13 is a flowchart of an example of the embodiment (part 3) of the method for producing a printed circuit board. FIG. 14 is a schematic diagram of an apparatus configuration for explaining one example of an embodiment (part 3) of the method for producing a wired circuit board.

(Method of manufacturing a wired circuit board)
The method for producing a wired circuit board of the present invention includes a first step, a second step, and a third step, and may further include other steps such as a fourth step, a fifth step, and a sixth step, as necessary.
First step: a step of subjecting waste liquid of the wiring circuit forming treatment liquid used in the wiring circuit forming step to at least one of electrochemical treatment and dialysis treatment (hereinafter, sometimes referred to as "recovery treatment") to obtain a recovered treatment liquid containing treatment liquid components. Second step: a step of preparing a reused wiring circuit forming treatment liquid using the recovered treatment liquid. Third step: a step of forming a wiring circuit using the reused wiring circuit forming treatment liquid.

In the manufacture of wired circuit boards, a method for manufacturing wired circuit boards that reduces the environmental impact can be provided by forming the wiring circuits using a treatment liquid for forming recycled wiring circuits.

It is preferable that the first, second, and third steps are carried out in one facility, which can reduce the transportation costs of the treatment solution components obtained by the recovery process and the treatment solution for forming a reused wiring circuit, as well as the environmental load (e.g., gasoline consumption and exhaust gas) caused by the transportation, thereby further reducing the environmental load and reducing costs.
A single business establishment may have multiple buildings.
When the first step, the second step, and the third step are carried out within one business establishment, the building in which the first step is carried out, the building in which the second step is carried out, and the building in which the third step is carried out may be the same building or different buildings.

Furthermore, it is preferable that the wiring circuit forming process and waste liquid recovery processing in the first process are performed in one facility, which can reduce the cost of transporting the waste liquid and the environmental load caused by the transport (e.g., gasoline consumption and exhaust gas), thereby further reducing the environmental load and reducing costs.
When the wiring circuit formation process and the waste liquid recovery processing are carried out within a single business establishment, the building in which the patterned insulating layer formation process is carried out, the building in which the waste liquid recovery processing is carried out, and the building in which the treatment liquid for forming the reused wiring circuit is prepared may be the same building or different buildings.

The waste liquid, the recovered processing liquid, and the processing liquid for forming a reused wiring circuit contain, for example, an acid as a processing liquid component.
The waste liquid, the recovered processing liquid, and the processing liquid for forming a reused wiring circuit are, for example, aqueous solutions.
The waste liquid, the recovered processing liquid, and the processing liquid for forming the reused wiring circuit include, for example, alcohol and water.
The acid may be an inorganic acid or an organic acid.
Examples of the inorganic acid include sulfuric acid, hydrochloric acid, nitric acid, phosphoric acid, boric acid, and hydrogen peroxide.
Examples of organic acids include formic acid, acetic acid, oxalic acid, propionic acid, benzoic acid, glycolic acid, salicylic acid, glyceric acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, maleic acid, phthalic acid, malic acid, tartaric acid, citric acid, lactic acid, glycine, alanine, aspartic acid, glutamic acid, aminomethanesulfonic acid, taurine, benzenesulfonic acid, toluenesulfonic acid, methanesulfonic acid, ethanesulfonic acid, and sulfamic acid.
Examples of the alcohol include methanol, ethanol, isopropanol, butanol, ethylene glycol, propylene glycol, and diethylene glycol.

<First step>
The first step is a step of subjecting waste liquid of a wiring circuit forming treatment liquid used in a wiring circuit forming step to at least one of a recovery treatment, such as an electrochemical treatment or a dialysis treatment, to obtain a recovered treatment liquid containing treatment liquid components.

The process for forming the wiring circuit may be, for example, a subtractive method or a semi-additive method.
In the semi-additive method, for example, plating is performed.
In the semi-additive method, for example, a seed layer is formed. The seed layer is a layer that serves as a base when plating is performed.

The process for forming the wiring circuit is not particularly limited, but includes, for example, washing of the metal substrate. The washing of the metal substrate is carried out, for example, before the formation of an insulating layer or a resist pattern. In the washing of the metal substrate, a metal oxide film (e.g., copper oxide), a rust inhibitor (e.g., benzotriazole), and the like on the surface of the metal substrate are removed.
The process of forming the wiring circuit includes, for example, a rinsing process after a development process in forming a resist pattern.
The process of forming the wiring circuit includes, for example, removing (etching) the seed layer.

Furthermore, the process of forming the wiring circuit includes, for example, at least one of forming a patterned insulating layer using a photosensitive resin composition for forming an insulating layer, forming a resist pattern using a resist material, and performing plating between the resist patterns on the seed layer.

The treatment liquid for forming a wiring circuit used in the first step may be a treatment liquid for forming a reused wiring circuit, a treatment liquid for forming a new wiring circuit, or a mixture of a treatment liquid for forming a reused wiring circuit and a treatment liquid for forming a new wiring circuit.

The wiring circuit forming treatment liquid is not particularly limited as long as it is a liquid used in the wiring circuit forming process, and examples thereof include a cleaning liquid, a rinsing liquid, and an etching liquid.
The cleaning solution may be, for example, an acidic cleaning solution.
The rinse liquid may be, for example, an acid rinse liquid.
The etching solution may be, for example, an acidic etching solution.

The treatment liquid for forming the wiring circuit includes, for example, at least one of an acidic cleaning liquid for cleaning the surface in the wiring circuit formation process and an acidic etching liquid for etching in the wiring circuit formation process.

The waste liquid is not particularly limited as long as it is a waste liquid from a processing liquid for forming a wiring circuit used in the wiring circuit forming process, and examples thereof include waste liquid from a cleaning liquid, waste liquid from a rinsing liquid, waste liquid from an etching liquid, and combinations of two or more of these.
The waste liquid preferably contains at least one of the following waste liquids (1) to (3).
(1) Waste liquid from cleaning solutions used in cleaning metal substrates prior to the formation of an insulating layer or resist pattern. (2) Waste liquid from rinsing solutions used in rinsing treatments following development treatments in the formation of resist patterns. (3) Waste liquid from etching solutions used in the removal (etching) of seed layers.

By carrying out various treatments using the treatment liquid for forming a wiring circuit, the waste liquid from the treatment liquid for forming a wiring circuit contains unnecessary components.
Examples of unnecessary components contained in the waste liquid include metal ions, such as copper ions, nickel ions, iron ions, titanium ions, and chromium ions.
For example, when a copper substrate as a metal substrate is cleaned, the waste cleaning liquid contains copper ions.
When the nickel seed layer is removed, the waste liquid of the etching solution contains nickel ions. In addition, when the seed layer is removed, the etching solution also etches a part of the plating layer, so that the waste liquid of the etching solution contains, for example, copper ions derived from the copper plating layer.

<<Waste liquid recovery and treatment>>
The waste liquid recovery treatment is not particularly limited as long as it is at least one of an electrochemical treatment and a dialysis treatment.
The recovery treatment may be an electrochemical treatment, a dialysis treatment, or an electrodialysis treatment that is a combination of these. Among these, the electrodialysis treatment is preferred in that it provides a high reuse rate of the wiring circuit forming treatment solution.

The electrochemical treatment is not particularly limited as long as it is a treatment that uses electricity to obtain a recovered treatment liquid containing treatment liquid components from waste liquid. For example, it can be a treatment in which waste liquid is placed in a recovery treatment chamber containing electrodes and electricity is passed through to cause unnecessary components (e.g., metal components) to adhere to the electrodes, thereby obtaining a recovered treatment liquid containing the treatment liquid components from which the unnecessary components have been removed.

The dialysis process is not particularly limited as long as it is a process that uses a dialysis membrane to obtain a recovered treatment liquid containing treatment liquid components from waste liquid. For example, it can be a process that uses an ion exchange membrane as the dialysis membrane to separate metal components (metal cations) and anion components (e.g., anions that are ionized components of acids; e.g., sulfate ions, chloride ions, nitrate ions, etc.) using osmotic pressure to obtain a recovered treatment liquid containing anion components as treatment liquid components.

The electrodialysis process is not particularly limited as long as it is a process that uses electricity and a dialysis membrane to obtain a recovered treatment liquid containing treatment liquid components from waste liquid. For example, it can be a process that uses electrodes and an ion exchange membrane as a dialysis membrane to separate metal components (metal cations) and anion components (e.g., anions that are ionized components of acids; e.g., sulfate ions, chloride ions, nitrate ions, etc.) using electrical energy and osmotic pressure to obtain a recovered treatment liquid containing acids as treatment liquid components.

An example of the electrodialysis treatment will now be described with reference to FIG.
The electrodialysis device 1001 shown in FIG.
In the electrodialysis tank 1002, a first tank 1011, a second tank 1012, and a third tank 1013 are disposed.
The first tank 1011 and the second tank 1012 are separated by a cation exchange membrane 1021 .
The first tank 1011 and the third tank 1013 are separated by a cation exchange membrane 1021 .
The electrodialysis cell 1002 further includes a first electrode 1031 and a second electrode 1032 .
The first electrode 1031 is disposed on the side of the second tank 1012 opposite to the first tank 1011 side.
An anion exchange membrane 1022 is disposed on the first electrode 1031 side of the second tank 1012 .
The second electrode 1032 is disposed on the side of the third tank 1013 opposite to the first tank 1011 side.
An anion exchange membrane 1022 is disposed on the second electrode 1032 side of the third tank 1013 .
In the electrodialysis device 1001, the first electrode 1031 is a positive electrode, and the second electrode 1032 is a negative electrode.

In the explanation using Fig. 1, the waste liquid is an aqueous solution containing Ni cations, Cu cations, and nitrate ions. The component to be recovered and reused is the nitrate ions.
The waste liquid is passed through the first tank 1011. Water with a relatively small amount of ions in the waste liquid is passed through the second tank 1012 and the third tank 1013. Examples of such water include deionized water and pure water. Due to osmotic pressure, nitrate ions permeate the cation exchange membrane 1021 and move to the second tank 1012 and the third tank 1013. On the other hand, Ni cations and Cu cations cannot permeate the cation exchange membrane 1021 and therefore remain in the first tank 1011. Furthermore, electricity acts, and more nitrate ions are collected in the second tank 1012 on the side where the first electrode 1031, which is the positive pole, is located. As a result, Ni cations, Cu cations, and nitrate ions are separated from the waste liquid, and a recovery treatment liquid in which nitrate ions have been recovered is obtained in the second tank 1012 and the third tank 1013.

There are no particular limitations on the processing time for waste liquid recovery processing.

<<Formation of a patterned insulating layer>>
In the process of forming a wiring circuit, for example, a patterned insulating layer is formed using a photosensitive resin composition for forming an insulating layer (sometimes referred to as a "pattern forming process").

The photosensitive resin composition for forming an insulating layer is not particularly limited as long as it is a photosensitive resin composition that can be used to form an insulating layer.
The photosensitive resin composition for forming an insulating layer may be in a liquid form or a film form (so-called dry film).
The photosensitive resin composition for forming an insulating layer may be a positive type in which the exposed portion is soluble in a developer, or a negative type in which the unexposed portion is soluble in a developer.
The insulating layer-forming photosensitive resin composition contains, for example, a resin. The insulating layer-forming photosensitive resin composition may contain, in addition to the resin, a crosslinking agent, a filler, various additives, and the like.
The photosensitive resin composition for forming an insulating layer contains, for example, a polyamic acid.
Examples of the photosensitive resin composition for forming an insulating layer include the negative photosensitive material described in JP-A-7-179604, the photosensitive resin composition described in JP-A-2005-266075, and the polyimide precursor composition described in JP-A-2013-100441.

The patterning process is performed by, for example, photolithography.
The photolithography may be a subtractive method or a semi-additive method.
The shape of the pattern to be formed is not particularly limited, and examples thereof include lines, lattices, dots, etc. Examples of dots include circles, ellipses, and polygons (such as squares).

Photolithography involves, for example, exposure, development, and post-exposure baking.
In photolithography, for example, a photomask is used during exposure. The exposure may be direct imaging exposure (direct writing exposure) without using a photomask. In direct imaging exposure, a laser beam is generally used as the exposure light.
The wavelength of the exposure light is not particularly limited, and may be, for example, 210 nm to 440 nm.
The light source of the exposure light is not particularly limited, and examples thereof include low-pressure mercury lamps (germicidal lamps, fluorescent chemical lamps, black lights), high-pressure discharge lamps (high-pressure mercury lamps, metal halide lamps), short arc discharge lamps (ultra-high pressure mercury lamps, xenon lamps, mercury-xenon lamps), light-emitting diodes (LEDs), and the like.
The amount of radiation in the exposure is not particularly limited, and may be, for example, 5 mJ/cm ² to 1,000 mJ/cm ² .
The development may be carried out using a solvent or an alkali.
The development may be a dip development or a spray development.
After the exposure and before the development, post-exposure baking may be performed as necessary. The post-exposure baking is appropriately performed depending on the type of the photosensitive resin composition for forming an insulating layer.

The developer used in the pattern formation process may be an alkaline developer or an organic solvent developer.
The alkaline developer contains, for example, an alkali and water, and may further contain an alcohol.

<<Formation of Resist Pattern>>
In the process of forming the wiring circuit, for example, a resist pattern is formed using a resist material (sometimes referred to as a "resist pattern forming process").

There are no particular limitations on the resist material, so long as it is a resist material that can be used to form a resist pattern.
The resist material may be in a liquid form or a film form (so-called dry film).
The resist material may be a positive type in which the exposed areas are soluble in a developer, or a negative type in which the unexposed areas are soluble in a developer.
The resist material contains, for example, a resin. The resist material may contain various additives in addition to the resin.
The resist pattern formed from the resist material is removed by a peeling process after the wiring circuit is formed. In this respect, the resist material is also called, for example, an etching resist. The patterned film formed from the photosensitive resin composition for forming an insulating layer is different from the resist pattern formed from the resist material, and remains as a part of the wiring circuit board as an insulating layer even after the wiring circuit is formed. Therefore, the photosensitive resin composition for forming an insulating layer is sometimes called a permanent resist in terms of distinction from the resist material in this specification.

The resist pattern forming step is performed by, for example, photolithography.
The photolithography may be a subtractive method or a semi-additive method.
The shape of the pattern to be formed is not particularly limited, and examples thereof include lines, lattices, dots, etc. Examples of dots include circles, ellipses, and polygons (such as squares).

In photolithography, for example, exposure, development, and the like are performed.
In photolithography, for example, a photomask is used during exposure. The exposure may be direct imaging exposure (direct writing exposure) without using a photomask. In direct imaging exposure, a laser beam is generally used as the exposure light.
The wavelength of the exposure light is not particularly limited, and may be, for example, 210 nm to 440 nm.
The light source of the exposure light is not particularly limited, and examples thereof include low-pressure mercury lamps (germicidal lamps, fluorescent chemical lamps, black lights), high-pressure discharge lamps (high-pressure mercury lamps, metal halide lamps), short arc discharge lamps (ultra-high pressure mercury lamps, xenon lamps, mercury-xenon lamps), light-emitting diodes (LEDs), and the like.
The amount of radiation in the exposure is not particularly limited, and may be, for example, 5 mJ/cm ² to 1,000 mJ/cm ² .
The development may be carried out using a solvent or an alkali.
The development may be a dip development or a spray development.

The developer used in the resist pattern formation process may be an alkaline developer or an organic solvent developer.
The alkaline developer contains, for example, an alkali and water, and may further contain an alcohol.

Before the resist pattern is formed, for example, a seed layer is formed. The resist pattern is formed, for example, on the seed layer. Then, after the resist pattern is formed, for example, plating is performed between the resist patterns.

<Plating between resist patterns>
As a method for plating between the resist patterns, for example, there is a method for plating between the resist patterns on the seed layer, in which electrolytic plating is usually performed.
The plating solution may be, for example, a copper sulfate plating solution.
An example of a method for plating is to immerse a laminate having a resist pattern formed on a seed layer in a plating solution.

After plating is applied between the resist patterns on the seed layer, the resist pattern is peeled off and the seed layer is removed, for example.

<Second step>
The second step is a step of preparing a treatment liquid for forming a reused wiring circuit using the recovered treatment liquid.
In the second step, the recovered treatment liquid may be used as it is as a treatment liquid for forming a reused wiring circuit.
In the second step, the recovered treatment liquid may be mixed with a new treatment liquid for forming a wiring circuit to prepare a reused treatment liquid for forming a wiring circuit.
In the second step, the treatment liquid for forming a reused wiring circuit may be prepared by adjusting the concentration of the treatment liquid components in the recovered treatment liquid. For example, the treatment liquid for forming a reused wiring circuit may be prepared by mixing the recovered treatment liquid with at least one of water, an acid, and an alcohol.

In the second step, the treatment liquid for forming a reused wiring circuit may be prepared by carrying out the following steps (1) and (2).
Step (1): A step of measuring the effective components in the recovered treatment liquid. Step (2): A step of adjusting the composition of the recovered treatment liquid to a predetermined composition using the measurement results of the effective components, thereby preparing a treatment liquid for forming a reused wiring circuit.

In step (1), for example, when the treatment liquid for forming a wiring circuit is an acidic liquid, the concentration of the acid as an active ingredient is measured. The measurement method is not particularly limited, and examples thereof include specific gravity measurement, neutralization titration, and combinations thereof. These measurements may be performed automatically or manually.
In step (2), the treatment liquid for forming a reused wiring circuit is prepared by adding acid or water to the recovered treatment liquid based on the measurement result of the acid concentration obtained in step (1) to adjust the composition to a predetermined value. The addition of acid or water to the recovered treatment liquid may be performed automatically or manually.
In steps (1) and (2), the measurement and adjustment may be performed automatically or manually.
In addition, when the wiring circuit forming treatment liquid contains alcohol, the concentration of the alcohol as an active ingredient may be measured in step (1), and in step (2), based on the measurement result of the alcohol concentration obtained in step (1), alcohol or water may be added to the recovered treatment liquid to adjust the composition to a predetermined value, thereby preparing the reuse wiring circuit forming treatment liquid.

<Third step>
The third step is a step of forming a wiring circuit using a treatment liquid for forming a reused wiring circuit.

The process for forming the wiring circuit is not particularly limited, but may include, for example, at least one of the following: forming a patterned insulating layer using a photosensitive resin composition for forming an insulating layer, forming a resist pattern using a resist material, and plating between the resist patterns on the seed layer.

The process for forming the wiring circuit may be, for example, a subtractive method or a semi-additive method.
In the semi-additive method, for example, plating is performed.
In the semi-additive method, for example, a seed layer is formed. The seed layer is a layer that serves as a base when plating is performed.

The process of forming the wiring circuit includes, for example, cleaning of the metal substrate. The cleaning of the metal substrate is performed, for example, before the formation of an insulating layer or a resist pattern. In the cleaning of the metal substrate, a metal oxide film (e.g., copper oxide), a rust inhibitor (e.g., benzotriazole), and the like on the surface of the metal substrate are removed.
The process of forming the wiring circuit includes, for example, a rinsing process that follows a development process in forming a resist pattern.
The process of forming the wiring circuit includes, for example, removing the seed layer.

In the method for producing a wired circuit board, the waste liquid of the treatment liquid for forming the reused wired circuit generated in the third step may be subjected to a recovery treatment and further reused.
That is, the method for producing the wired circuit board may include the following fourth, fifth, and sixth steps. Furthermore, in the method for producing the wired circuit board, the fourth to sixth steps may be repeated multiple times.
Fourth step: A step of subjecting the waste liquid of the treatment liquid for forming the reused wiring circuit used in the third step to at least one of electrochemical treatment and dialysis treatment to obtain a second recovered treatment liquid containing a treatment liquid component. Fifth step: A step of preparing a treatment liquid for forming a second reused wiring circuit using the second recovered treatment liquid. Sixth step: A step of forming a wiring circuit using the treatment liquid for forming the second reused wiring circuit.

Specific examples and preferred examples of the fourth step include the same specific examples and preferred examples as those given in the explanation of the first step.
Specific examples and preferred examples of the fifth step include the same specific examples and preferred examples as those given in the explanation of the second step.
Specific examples and preferred examples of the sixth step include the same specific examples and preferred examples as those given in the explanation of the third step.

Below are embodiments (part 1) to (part 3) of the method for manufacturing a wired circuit board.

<Embodiment 1>
In the embodiment (part 1) of the method for producing a wired circuit board, the first to third steps are as follows.
First step: A step of subjecting a waste liquid of a cleaning liquid used for cleaning a first metal substrate to a recovery treatment to obtain a recovered treatment liquid containing a cleaning liquid component (step 1A).
Second step: preparing a reused recovered treated liquid using the recovered treated liquid (step 2A)
Third step: A step of cleaning the second metal substrate using the recycled treatment liquid (step 3A)
In the first embodiment, the treatment liquid for forming a wiring circuit is a cleaning liquid.

<<Step 1A>>
Step 1A is a step of subjecting a waste liquid of a cleaning liquid used for cleaning a first metal substrate to a recovery treatment to obtain a recovered treatment liquid containing a cleaning liquid component.

The cleaning liquid used in step 1A may be a recycled cleaning liquid, a new cleaning liquid, or a mixture of recycled cleaning liquid and new cleaning liquid.

The cleaning solution is, for example, an acidic aqueous solution. In this case, the cleaning solution component is an acid.

The first metal substrate is, for example, an element for ensuring the rigidity of the printed circuit board.
The first metal substrate is, for example, a metal core layer.
The material of the first metal substrate is not particularly limited, and examples thereof include Cu, Cu alloy, stainless steel, alloy 42, etc. Among these, from the viewpoint of thermal conductivity and electrical conductivity, Cu, Cu alloy, and stainless steel are preferable.
The thickness of the first metal substrate is not particularly limited and is, for example, 10 μm or more, preferably 15 μm or more, and for example, 500 μm or less, preferably 300 μm or less.

The method for cleaning the first metal substrate is not particularly limited, and examples thereof include a method of immersing the metal substrate in a cleaning liquid, and a method of spraying the cleaning liquid onto the metal substrate.
The cleaning time for the first metal substrate is not particularly limited.
The temperature of the cleaning solution used when cleaning the first metal substrate is not particularly limited.

　Examples of the method for recovering the waste liquid in step 1A include the recovery methods listed in <<Recovery of waste liquid>> in step 1.

<<Step 2A>>
Step 2A is a step of preparing a reused cleaning liquid using the recovered treatment liquid.
In the step 2A, the recovered treatment liquid may be used as a reused cleaning liquid as it is.
In step 2A, the recovered treatment liquid may be mixed with a new cleaning liquid to prepare a reused cleaning liquid.
In the step 2A, the reuse cleaning liquid may be prepared by adjusting the concentration of the cleaning liquid component in the recovered processing liquid. For example, the reuse cleaning liquid may be prepared by mixing the recovered processing liquid with at least one of water, an acid, and an alcohol.

In step 2A, the reuse cleaning liquid may be prepared by carrying out the following steps (1A) and (2A).
Step (1A): A step of measuring the amount of active ingredients in the recovered treatment liquid. Step (2A): A step of adjusting the composition of the recovered treatment liquid to a predetermined composition using the measurement results of the active ingredients, thereby preparing a reused cleaning liquid.

In step (1A), for example, when the cleaning solution is an acidic aqueous solution, the concentration of the acid as an active ingredient is measured. The measurement method is not particularly limited, and examples thereof include specific gravity measurement, neutralization titration, and combinations thereof. These measurements may be performed automatically or manually.
In step (2A), based on the measurement result of the acid concentration obtained in step (1A), an acid or water is added to the recovered treatment liquid to adjust the composition to a predetermined value, thereby preparing a reused cleaning liquid. The addition of the acid or water to the recovered treatment liquid may be performed automatically or manually.
In steps (1A) and (2A), the measurement and adjustment may be performed automatically or manually.
In addition, when the cleaning solution contains alcohol, the concentration of the alcohol as an active ingredient may be measured in step (1A), and in step (2A), a reuse cleaning solution may be prepared by adding alcohol or water to the recovered treatment solution to adjust the composition to a predetermined value based on the measurement result of the alcohol concentration obtained in step (1A).

<<Step 3A>>
The 3A step is a step of cleaning the second metal substrate with the recycled treatment liquid.

The second metal substrate is, for example, an element for ensuring the rigidity of the printed circuit board.
The second metal substrate is, for example, a metal core layer.
The material of the second metal substrate is not particularly limited, and examples thereof include Cu, Cu alloy, stainless steel, alloy 42, etc. Among these, from the viewpoint of thermal conductivity and electrical conductivity, Cu, Cu alloy, and stainless steel are preferable.
The thickness of the second metal substrate is not particularly limited and is, for example, 10 μm or more, preferably 15 μm or more, and for example, 500 μm or less, preferably 300 μm or less.

The method for cleaning the second metal substrate is not particularly limited, and examples thereof include a method of immersing the metal substrate in a cleaning liquid, and a method of spraying the cleaning liquid onto the metal substrate.
The cleaning time for the second metal substrate is not particularly limited.
The temperature of the cleaning liquid when cleaning the second metal substrate is not particularly limited.

The first metal substrate and the second metal substrate may be made of the same material or different materials.
The first metal substrate and the second metal substrate may be the same size or may be different sizes.
The first metal substrate and the second metal substrate may have the same thickness or different thicknesses.

The first metal substrate and the second metal substrate may be metal substrates used in the same process, or may be metal substrates used in different processes.
An example of the same process is a process for forming wiring circuits of the same pattern shape.

In the embodiment (part 1) of the method for producing a wired circuit board, the waste cleaning liquid generated in the step 3A may be subjected to a recovery process and further reused.
That is, the embodiment (part 1) of the method for producing a wired circuit board may include the following steps 4A, 5A, and 6A. Furthermore, in the embodiment (part 1) of the method for producing a wired circuit board, steps 4A to 6A may be repeated multiple times.
Step 4A: A step of subjecting the waste liquid of the reused cleaning liquid used in Step 3A to a recovery process to obtain a second recovered processing liquid containing cleaning liquid components. Step 5A: A step of preparing a second reused cleaning liquid using the second recovered processing liquid. Step 6A: A step of cleaning a third metal substrate using the reused recovered processing liquid. Note that Step 4A is one embodiment of Step 4.
Step 5A is an embodiment of step 5.
Step 6A is an embodiment of Step 6.

Specific examples and preferred examples of Step 4A include the same specific examples and preferred examples as those given in the explanation of Step 1A.
Specific examples and preferred examples of Step 5A include the same specific examples and preferred examples as those given in the explanation of Step 2A.
Specific examples and preferred examples of Step 6A include the same specific examples and preferred examples as those given in the explanation of Step 3A.

<Embodiment 2>
In the second embodiment of the method for producing a wired circuit board, the first to third steps are as follows.
First step: a step of recovering a waste liquid of a rinse solution used in a rinse treatment after a development treatment in forming a first resist pattern, to obtain a recovered treatment liquid containing a rinse solution component (first B step).
Second step: preparing a reused rinse liquid using the recovered treatment liquid (step 2B)
Third step: A step of performing a rinsing treatment after the development treatment in forming the second resist pattern using the recycled rinsing liquid (Step 3B).
In the second embodiment, the processing liquid for forming a wiring circuit is a rinse liquid.

<<Step 1B>>
Step 1B is a step of recovering a waste liquid of a rinse liquid used in a rinse treatment after a development treatment in forming a first resist pattern, to obtain a recovered treatment liquid containing a rinse liquid component.

The rinse liquid used in step 1B may be a recycled rinse liquid, a new rinse liquid, or a mixture of a recycled rinse liquid and a new rinse liquid.

The rinse solution is, for example, an acid rinse solution. In this case, the rinse solution component is an acid.

The method of rinsing is not particularly limited, and examples thereof include a method of immersing the resist pattern in a cleaning liquid, and a method of spraying the cleaning liquid onto the resist pattern.
The rinsing time is not particularly limited.
The temperature of the rinse liquid during the rinse treatment is not particularly limited.

An example of a method for forming the first resist pattern is the resist pattern formation process described above.

<<Step 2B>>
Step 2B is a step of preparing a reused rinse liquid using the recovered processing liquid.
Step 2B is one embodiment of step 2. The reused rinse liquid in step 2B corresponds to the reused wiring circuit forming treatment liquid in step 2.
Specific examples and preferred examples of Step 2B include the same specific examples and preferred examples as those given in the explanation of Step 2.

<<Step 3B>>
The 3B step is a step of performing a rinsing treatment using a recycled rinsing liquid after the development treatment in forming the second resist pattern.

The method of rinsing is not particularly limited, and examples thereof include a method of immersing the resist pattern in a rinsing liquid, and a method of spraying the rinsing liquid onto the resist pattern.
The rinsing time is not particularly limited.
The temperature of the rinse liquid during the rinse treatment is not particularly limited.

An example of a method for forming the second resist pattern is the resist pattern formation process described above.

The method for forming the first resist pattern and the method for forming the second resist pattern may be the same process or different processes. An example of the same process is a process for forming resist patterns of the same shape.

In the embodiment (part 2) of the method for producing a wired circuit board, the waste rinsing liquid generated in the step 3B may be subjected to a recovery process and further reused.
That is, the embodiment (part 2) of the method for producing a wired circuit board may include the following steps 4B, 5B, and 6B. Furthermore, in the embodiment (part 2) of the method for producing a wired circuit board, steps 4B to 6B may be repeated multiple times.
Step 4B: A step of subjecting the waste liquid of the reused rinse liquid used in Step 3B to a recovery process to obtain a second recovered treatment liquid containing a rinse liquid component. Step 5B: A step of preparing a second reused rinse liquid using the second recovered treatment liquid. Step 6B: A step of performing a rinse process after the development process in forming a third resist pattern using the second reused rinse liquid. Note that Step 4B is one embodiment of Step 4.
Step 5B is an embodiment of step 5.
Step 6B is an embodiment of step 6.

Specific examples and preferred examples of Step 4B include the same specific examples and preferred examples as those given in the explanation of Step 1B.
Specific examples and preferred examples of Step 5B include the same specific examples and preferred examples as those given in the explanation of Step 2B.
Specific examples and preferred examples of Step 6B include the same specific examples and preferred examples as those given in the explanation of Step 3B.

<Embodiment 3>
In the third embodiment of the method for producing a wired circuit board, the first to third steps are as follows.
First step: A step of subjecting a waste liquid of the etching solution used for removing the first seed layer to a recovery treatment to obtain a recovered treatment liquid containing an etching solution component (first C step).
Second step: preparing a reused etching solution using the recovered treatment solution (second C step)
Third step: removing the second seed layer using the recycled etching solution (third step C)
In the third embodiment, the treatment liquid for forming a wiring circuit is an etching liquid.

<<First C Step>>
The 1C step is a step of subjecting a waste liquid of the etching solution used in removing the first seed layer to a recovery treatment to obtain a recovered treatment liquid containing an etching solution component.

The etching solution used in step 1C may be a recycled etching solution, a new etching solution, or a mixture of a recycled etching solution and a new etching solution.

The etching solution is, for example, an acidic etching solution. In this case, the etching solution component is an acid.

The method for removing the first seed layer is not particularly limited, and examples thereof include a method of immersing the seed layer in an etching solution, a method of spraying the etching solution onto the seed layer, etc. When a plating pattern is formed on the seed layer, the seed layer is usually immersed in the etching solution together with the plating pattern.
The time for removing the first seed layer is not particularly limited.
The temperature of the etching solution when removing the first seed layer is not particularly limited.

<<Second C step>>
The 2C step is a step of preparing a reused etching liquid using the recovered treated liquid.
Step 2C is one embodiment of Step 2. The reused etching liquid in Step 2C corresponds to the reused wiring circuit forming treatment liquid in Step 2.
Specific examples and preferred examples of Step 2C include the same specific examples and preferred examples as those given in the explanation of Step 2.

<<Step 3C>>
Step 3C is a step of removing the second seed layer by using the recycled etching solution.

The method for removing the second seed layer is not particularly limited, and examples thereof include a method of immersing the seed layer in an etching solution, a method of spraying the etching solution onto the seed layer, etc. When a plating pattern is formed on the seed layer, the seed layer is usually immersed in the etching solution together with the plating pattern.
The time for removing the second seed layer is not particularly limited.
The temperature of the etching solution when removing the second seed layer is not particularly limited.

The first seed layer and the second seed layer may be seed layers used in the same process, or may be seed layers used in different processes.
An example of the same process is a process for forming wiring circuits of the same pattern shape.

In the embodiment (third) of the method for producing a wired circuit board, the waste etching solution generated in the third C step may be subjected to a recovery process and further reused.
That is, the embodiment (part 3) of the method for producing a wired circuit board may include the following steps 4C, 5C, and 6C. Furthermore, in the embodiment (part 3) of the method for producing a wired circuit board, steps 4C to 6C may be repeated multiple times.
Step 4C: A step of subjecting the waste liquid of the recycled etching liquid used in Step 3C to a recovery process to obtain a second recovered processing liquid containing an etching liquid component. Step 5C: A step of preparing a second recycled etching liquid using the second recovered processing liquid. Step 6C: A step of removing the third seed layer using the second recycled etching liquid. Note that Step 4C is one embodiment of Step 4.
Step 5C is an embodiment of step 5.
Step 6C is an embodiment of step 6.

Specific examples and preferred examples of Step 4C include the same specific examples and preferred examples as those given in the explanation of Step 1C.
Specific examples and preferred examples of Step 5C include the same specific examples and preferred examples as those given in the explanation of Step 2C.
Specific examples and preferred examples of Step 6C include the same specific examples and preferred examples as those given in the explanation of Step 3C.

Hereinafter, an embodiment of a method for manufacturing a printed circuit board will be described with reference to the drawings.
FIG. 2 is a flow chart of one embodiment of a method for manufacturing a printed circuit board.
First, the first step 101 is carried out. In the first step 101, waste liquid of the wiring circuit forming treatment liquid used in the wiring circuit forming step is subjected to a recovery treatment to obtain a recovered treatment liquid containing a treatment liquid component.
Next, a second step 102 is performed. In the second step 102, the recovered treatment liquid obtained in the first step 101 is used to prepare a treatment liquid for forming a reused wiring circuit.
Next, a third step 103 is performed. In the third step 103, the reuse wiring circuit forming treatment liquid prepared in the second step 102 is used to form a wiring circuit.

FIG. 3 is a flow chart of another embodiment of the method for manufacturing a printed circuit board.
First, the first step 101 to the third step 103 are performed. The first step 101 to the third step 103 are the same as the first step 101 to the third step 103 in the description of one embodiment of the method for producing a wired circuit board using FIG.
Next, a fourth step 104 is performed. In the fourth step 104, the waste liquid of the processing liquid for forming the reused wiring circuit used in the third step 103 is subjected to a recovery process to obtain a second recovered processing liquid containing a processing liquid component.
Next, a fifth step 105 is performed. In the fifth step 105, the second recovered processing liquid obtained in the fourth step 104 is used to prepare a second processing liquid for forming a reused wiring circuit.
Next, a sixth step 106 is performed. In the sixth step 106, the second reuse wiring circuit forming treatment liquid prepared in the fifth step 105 is used to form a wiring circuit.

FIG. 4 is a flow chart of another embodiment of the method for manufacturing a printed circuit board.
The flowchart in FIG. 4 illustrates an embodiment in which the fourth to sixth steps are performed multiple times.
The first step 101 to the sixth step 106 are performed. The first step 101 to the sixth step 106 are the same as the first step 101 to the sixth step 106 in the description of the embodiment of the method for producing a wired circuit board using FIG.
Next, a fourth step 104 is performed. In this fourth step 104, waste liquid from the treatment liquid for forming a wiring circuit used in the step of forming a wiring circuit in the sixth step 106 is used as the waste liquid from the treatment liquid for forming a wiring circuit.
Next, a fifth step 105 and a sixth step 106 are carried out.

Hereinafter, an embodiment (part 1) of the method for producing a printed circuit board will be described with reference to the drawings.
FIG. 5 is a flow chart of an example of an embodiment (part 1) of a method for manufacturing a printed circuit board.
First, the 1A step 1 is carried out. In the 1A step 1, a waste liquid of a cleaning liquid used for cleaning a first metal substrate is subjected to a recovery treatment to obtain a recovered treatment liquid containing a cleaning liquid component.
Next, the 2A step 2 is carried out. In the 2A step 2, the recovered and treated liquid obtained in the 1A step 1 is used to prepare a reused recovered and treated liquid.
Next, the 3A step 3 is carried out. In the 3A step 3, the second metal substrate is cleaned using the recycled treatment liquid.

FIG. 6 is a flowchart of another example of the embodiment (part 1) of the method for manufacturing a printed circuit board.
First, 1A step 1 to 3A step 3 are performed. 1A step 1 to 3A step 3 are the same as 1A step 1 to 3A step 3 in the description of the embodiment (part 1) of the method for producing a wired circuit board using FIG.
Next, the 4A step 4 is carried out. In the 4A step 4, the waste liquid of the reused cleaning liquid used in the 3A step 3 is subjected to a recovery treatment to obtain a second recovered treatment liquid containing a cleaning liquid component.
Next, the 5A step 5 is carried out. In the 5A step 5, the second recovered treatment liquid obtained in the 4A step 4 is used to prepare a second reuse cleaning liquid.
Next, the 6A step 6 is performed. In the 6A step 6, the third metal substrate is cleaned using the second recycled treatment liquid prepared in the 5A step 5.

FIG. 7 is a flowchart of another example of the embodiment (part 1) of the method for manufacturing a printed circuit board.
The flowchart in FIG. 7 illustrates an embodiment in which steps 4A to 6A are performed multiple times.
The 1A step 1 to the 6A step 6 are performed. The 1A step 1 to the 6A step 6 are the same as the 1A step 1 to the 6A step 6 in the description of the embodiment (part 1) of the method for producing a wired circuit board using FIG.
Next, the 4A step 4 is carried out. In the 4A step 4, the waste cleaning liquid used in cleaning the third metal substrate in the 6A step 6 is used as the waste cleaning liquid.
Next, step 5A5 and step 6A6 are carried out.

Hereinafter, an embodiment (part 1) of the method for producing a wired circuit board will be described with reference to a schematic diagram of an apparatus configuration.
FIG. 8 is a schematic diagram of an apparatus configuration for explaining one example of an embodiment (part 1) of the method for producing a wired circuit board.
In this embodiment, a cleaning liquid tank 11, a cleaning device 12, a waste liquid tank 13, a recovery and treatment device 14, and a recovery and treatment liquid tank 15 are used. Furthermore, piping is used to connect these devices.
In this embodiment, the concentration of the active ingredient is not adjusted, and the recovered treated liquid is used as it is as a reused cleaning liquid.
In one embodiment of the method for producing a printed circuit board described here, a first A step, a second A step, and a third A step are performed.
First, the 1A step is performed. In the 1A step, the waste liquid of the cleaning liquid used for cleaning the first metal substrate is subjected to a recovery process to obtain a recovery process liquid containing a cleaning liquid component. Specifically, the first metal substrate is cleaned by a cleaning device 12 using the cleaning liquid in a cleaning liquid tank 11. The cleaning liquid used for cleaning is sent as a waste liquid to a waste liquid tank 13. The waste liquid of the cleaning liquid is sent from the waste liquid tank 13 to a recovery process device 14. In the recovery process device 14, an electrodialysis process is performed as an example of a recovery process. The recovery process liquid obtained by performing the recovery process is sent to a recovery process liquid tank 15. The waste liquid other than the recovery process liquid is returned to the waste liquid tank 13, mixed with the waste liquid in the waste liquid tank 13, and sent again to the recovery process device 14.
Next, step 2A is performed. In step 2A, the recovered processing liquid is used to prepare a reused cleaning liquid. Specifically, if the recovered processing liquid sent to the recovered processing liquid tank 15 does not require concentration adjustment of the active ingredient, the recovered processing liquid is sent directly to the cleaning liquid tank 11 to become the reused cleaning liquid.
Next, step 3A is performed. In step 3A, the second metal substrate is cleaned using the reused cleaning liquid. Specifically, the second metal substrate is cleaned by the cleaning device 12 using the reused cleaning liquid in the cleaning liquid tank 11.
When the concentration of components other than those constituting the cleaning liquid in the waste liquid tank 13 reaches a certain level, the efficiency of the recovery process decreases, and the waste liquid is discarded.

FIG. 9 is a schematic diagram of an apparatus configuration for explaining another example of the embodiment (part 1) of the method for producing a wired circuit board.
In this embodiment, a cleaning liquid tank 11, a cleaning device 12, a waste liquid tank 13, a recovery and processing device 14, a recovery and processing liquid tank 15, an analysis device 16, and a supply device 17 are used. Furthermore, piping is used to connect these devices.
In this embodiment, the concentration of the active ingredient is adjusted in the cleaning liquid tank 11 using the analysis device 16 and the supply device 17, and the reused cleaning liquid is prepared using the recovered treatment liquid.
In one embodiment of the method for producing a printed circuit board described here, a first A step, a second A step, and a third A step are performed.
First, step 1A is performed. Step 1A is the same as step 1A in the description of the embodiment (part 1) of the method for producing a wired circuit board using FIG.
Next, step 2A is performed. In step 2A, the recovered processing liquid is used to prepare a reused cleaning liquid. Specifically, the recovered processing liquid sent to the recovered processing liquid tank 15 is further sent to the cleaning liquid tank 11. The recovered processing liquid in the cleaning liquid tank 11 is sampled, and the concentration of the active ingredient (e.g., acid) is measured by the analysis device 16. Then, based on the result, a predetermined amount of an ingredient (e.g., acid) for adjusting the concentration is supplied from the supply device 17 to the cleaning liquid tank 11. In this way, the concentration of the recovered processing liquid is adjusted in the cleaning liquid tank 11, and the reused cleaning liquid is prepared.
Next, step 3A is performed, which is the same as step 3A in the description of the embodiment (part 1) of the method for producing a wired circuit board using FIG.
In step 2A, the result of the measurement of the concentration of the active ingredient obtained by the analysis device 16 is sent to the supply device 17, for example, by wire or wirelessly.
The concentration adjustment in step 2A may be performed manually or automatically. For example, without using the supply device 17, a predetermined amount of a component (e.g., an acid) for adjusting the concentration may be manually supplied to the cleaning solution tank 11 based on the result of the concentration measurement of the active ingredient (e.g., an acid) obtained by the analysis device 16.
When the concentration of components other than those constituting the cleaning liquid in the waste liquid tank 13 reaches a certain level, the efficiency of the recovery process decreases, and the waste liquid is discarded.

FIG. 10 is a schematic diagram of an apparatus configuration for explaining another example of the embodiment (part 1) of the method for producing a wired circuit board.
In this embodiment, a cleaning liquid tank 11, a cleaning device 12, a waste liquid tank 13, a recovery and processing device 14, a recovery and processing liquid tank 15, an analysis device 16, and a supply device 17 are used. Furthermore, piping is used to connect these devices.
In this embodiment, the concentration of the active ingredient is adjusted in the recovered and treated liquid tank 15 using the analysis device 16 and the supply device 17, and the recovered and treated liquid is used to prepare a reused cleaning liquid.
In one embodiment of the method for producing a printed circuit board described here, a first A step, a second A step, and a third A step are performed.
First, step 1A is performed. Step 1A is the same as step 1A in the description of the embodiment (part 1) of the method for producing a wired circuit board using FIG.
Next, step 2A is performed. In step 2A, the recovered processing liquid is used to prepare a reused cleaning liquid. Specifically, the recovered processing liquid sent to the recovered processing liquid tank 15 is sampled, and the concentration of the active ingredient (e.g., acid) is measured by the analysis device 16. Then, based on the result, a predetermined amount of an ingredient for adjusting the concentration is supplied from the supply device 17 to the recovered processing liquid tank 15. In this way, the concentration of the recovered processing liquid is adjusted in the recovered processing liquid tank 15, and a reused cleaning liquid is prepared. The obtained reused cleaning liquid is sent to the cleaning liquid tank 11.
Next, step 3A is performed, which is the same as step 3A in the description of the embodiment (part 1) of the method for producing a wired circuit board using FIG.
In step 2A, the result of the measurement of the concentration of the active ingredient obtained by the analysis device 16 is sent to the supply device 17, for example, by wire or wirelessly.
The concentration adjustment in step 2A may be performed manually or automatically. For example, without using the supply device 17, a predetermined amount of a component (e.g., an acid) for adjusting the concentration may be manually supplied to the cleaning solution tank 11 based on the result of the concentration measurement of the active ingredient obtained by the analysis device 16.
When the concentration of components other than those constituting the cleaning liquid in the waste liquid tank 13 reaches a certain level, the efficiency of the recovery process decreases, and the waste liquid is discarded.

Hereinafter, a second embodiment of the method for producing a printed circuit board will be described with reference to the drawings.
FIG. 11 is a flowchart of an example of the embodiment (part 2) of the method for producing a printed circuit board.
First, the 1B step 21 is performed. In the 1B step 21, a waste liquid of a rinse liquid used in a rinse process after a development process in forming a first resist pattern is subjected to a recovery process to obtain a recovered treatment liquid containing a rinse liquid component.
Next, the 2B step 22 is performed. In the 2B step 22, the recovered processing liquid obtained in the 1B step 21 is used to prepare a reused rinse liquid.
Next, the 3B step 23 is performed. In the 3B step 23, the reused rinse liquid prepared in the 2B step 22 is used to perform a rinse treatment after the development treatment in the formation of the second resist pattern.

FIG. 12 is a schematic diagram of an apparatus configuration for explaining one example of an embodiment (part 2) of the method for producing a wired circuit board.
In this embodiment, a rinse liquid tank 31, a rinse device 32, a waste liquid tank 33, a recovery and processing device 34, a recovery and processing liquid tank 35, an analysis device 36, and a supply device 37 are used. Furthermore, piping is used to connect these devices.
In this embodiment, the concentration of the active ingredient is adjusted in the rinse liquid tank 31 using the analysis device 36 and the supply device 37, and the reused rinse liquid is prepared using the recovered treatment liquid.
In one embodiment of the method for producing a wired circuit board described here, a 1B step, a 2B step, and a 3B step are performed.
First, the 1B step is performed. In the 1B step, the waste liquid of the rinse liquid used in the rinse process after the development process in the formation of the first resist pattern is subjected to a recovery process to obtain a recovered treatment liquid containing a rinse liquid component. Specifically, the rinse liquid in the rinse liquid tank 31 is used by the rinse device 32 to perform a rinse process on the resist pattern after the development process in the formation of the first resist pattern. The rinse liquid used in the rinse process is sent to the waste liquid tank 33 as a waste liquid. The waste liquid of the rinse liquid is sent from the waste liquid tank 33 to the recovery treatment device 34. In the recovery treatment device 34, an electrodialysis process as an example of a recovery process is performed. The recovered treatment liquid obtained by performing the recovery process is sent to the recovery treatment liquid tank 35. The waste liquid other than the recovered treatment liquid is returned to the waste liquid tank 33, mixed with the waste liquid in the waste liquid tank 33, and sent again to the recovery treatment device 34.
Next, step 2B is performed. In step 2B, the recovered processing liquid is used to prepare a reused rinse liquid. Specifically, the recovered processing liquid sent to the recovered processing liquid tank 35 is further sent to the rinse liquid tank 31. The recovered processing liquid in the rinse liquid tank 31 is sampled, and the concentration of an active ingredient (e.g., an acid) is measured by an analyzer 36. Then, based on the result, a predetermined amount of an ingredient (e.g., an acid) for adjusting the concentration is supplied from a supply device 37 to the rinse liquid tank 31. In this way, the concentration of the recovered processing liquid is adjusted in the rinse liquid tank 31, and the reused rinse liquid is prepared.
Next, step 3B is performed. In step 3B, a rinse process is performed using a reused rinse liquid after the development process in the formation of the second resist pattern. Specifically, the rinse device 32 uses the reused rinse liquid in the rinse liquid tank 31 to rinse the resist pattern after the development process in the formation of the second resist pattern.
In step 2B, the result of the measurement of the concentration of the active ingredient obtained by the analysis device 36 is sent to the supply device 37, for example, by wire or wirelessly.
The concentration adjustment in step 2B may be performed manually or automatically. For example, without using the supply device 37, a predetermined amount of a component (e.g., an acid) for adjusting the concentration may be manually supplied to the rinse liquid tank 31 based on the result of the concentration measurement of the active ingredient (e.g., an acid) obtained by the analysis device 36.
When the concentration of components other than the components constituting the rinsing liquid in the waste liquid tank 33 becomes high to a certain extent, the efficiency of the recovery process decreases, and the waste liquid is discarded.

Hereinafter, a third embodiment of the method for producing a printed circuit board will be described with reference to the drawings.
FIG. 13 is a flowchart of an example of the embodiment (part 3) of the method for producing a printed circuit board.
First, the 1C step 41 is performed. In the 1C step 41, a waste liquid of the etching solution used for removing the first seed layer is subjected to a recovery process to obtain a recovered treatment liquid containing an etching solution component.
Next, a 2C step 42 is performed. In the 2C step 42, the recovered treated liquid obtained in the 1C step 41 is used to prepare a reused etching liquid.
Next, a 3C process 43 is performed. In the 3C process 43, the second seed layer is removed using the recycled etching solution prepared in the 2C process 42.

FIG. 14 is a schematic diagram of an apparatus configuration for explaining one example of an embodiment (part 3) of the method for producing a wired circuit board.
In this embodiment, an etching liquid tank 51, an etching device 52, a waste liquid tank 53, a recovery and processing device 54, a recovered and processed liquid tank 55, an analysis device 56, and a supply device 57 are used. Furthermore, piping is used to connect these devices.
In this embodiment, the concentration of the active ingredient is adjusted in the recovered and treated liquid tank 55 using the analysis device 56 and the supply device 57, and the recovered and treated liquid is used to prepare a reused etching liquid.
In one embodiment of the method for producing a printed circuit board described here, a first C step, a second C step, and a third C step are performed.
First, the 1C step is performed. In the 1C step, the waste liquid of the etching liquid used in removing the first seed layer is subjected to a recovery process to obtain a recovery process liquid containing an etching liquid component. Specifically, the etching liquid in the etching liquid tank 51 is used to etch the first seed layer by the etching device 52. The etching liquid used during the etching is sent to the waste liquid tank 53 as a waste liquid. The waste liquid of the etching liquid is sent from the waste liquid tank 53 to the recovery processing device 54. In the recovery processing device 54, an electrodialysis process as an example of a recovery process is performed. The recovery processing liquid obtained by performing the recovery process is sent to the recovery processing liquid tank 55. The waste liquid other than the recovery processing liquid is returned to the waste liquid tank 53, mixed with the waste liquid in the waste liquid tank 53, and sent again to the recovery processing device 54.
Next, the 2C step is performed. In the 2C step, the recovered processing liquid is used to prepare a reused etching liquid. Specifically, the recovered processing liquid sent to the recovered processing liquid tank 55 is sampled, and the concentration of the active ingredient (e.g., acid) is measured by the analysis device 56. Then, based on the result, a predetermined amount of an ingredient for adjusting the concentration is supplied from the supply device 57 to the recovered processing liquid tank 55. In this way, the concentration of the recovered processing liquid is adjusted in the recovered processing liquid tank 55, and a reused etching liquid is prepared. The obtained reused etching liquid is sent to the etching liquid tank 51.
Next, a process 3C is performed. In the process 3C, the second seed layer is removed using a recycled etching solution. Specifically, the second seed layer is etched by an etching device 52 using the recycled etching solution in an etching solution tank 51.
In step 2C, the result of the measurement of the concentration of the active ingredient obtained by the analysis device 56 is sent to the supply device 57, for example, by wire or wirelessly.
The concentration adjustment in the second C step may be performed manually or automatically. For example, without using the supply device 57, a predetermined amount of a component (e.g., an acid) for adjusting the concentration may be manually supplied to the etching solution tank 51 based on the result of the concentration measurement of the active ingredient obtained by the analysis device 56.
When the concentration of components other than those constituting the etching liquid in the waste liquid tank 53 becomes high to a certain extent, the efficiency of the recovery process decreases, and the waste liquid is discarded.

The following examples are provided to specifically explain the present invention, but the present invention is not limited to these.

[Test Example 1-1] Cleaning using recycled cleaning solution A cleaning test of a substrate was carried out using a recycled cleaning solution.

<Cleaning solution>
As the cleaning liquid, a 6% by mass aqueous solution of sulfuric acid was used.

<Preparation of waste liquid for testing>
Copper was dissolved in the cleaning liquid so that the copper ion concentration was 500 ppm by mass, to obtain a test waste liquid.

<Cleaning test substrate>
A circuit board having an oxide layer and a copper surface with a rust inhibitor (benzotriazole) attached thereto [a polyimide film (thickness 20 μm×10 cm×10 cm) with 20 μm of copper laminated thereon] was used as the cleaning test substrate.

<Electrodialysis treatment>
The electrodialysis treatment was carried out using the following electrodialysis apparatus.
・Electrodialysis device: Micro Acilyzer S3 (manufactured by Astom)
・Cation exchange membrane: CKP-S (manufactured by Astom)
・Anion exchange membrane: ASE (manufactured by Astom)
Each ion exchange membrane was attached to a Micro Acilyzer S3 (manufactured by Astom), which is an apparatus for testing electrodialysis.
At 23° C., 500 mL of the test waste liquid was introduced into the micro-acid lyzer S3, and electrodialysis treatment was performed by applying a voltage of 15 V with a current of up to 2 A. The electrodialysis treatment was performed for about 2 hours while circulating the test waste liquid at a flow rate of about 5 L/min.
The recovered treated liquid obtained by electrodialysis was used in the following cleaning test.

<Cleaning test>
500 mL of the recovered solution obtained by the electrodialysis treatment was placed in a 1000 mL beaker as a reused cleaning solution. A cleaning test substrate was placed in the 1000 mL beaker and cleaned at a temperature of 30° C. for 180 seconds.
During washing, the reused washing liquid was stirred using a magnetic stirrer.

The above test was evaluated as follows.
<Acid recovery rate>
The acid component (sulfuric acid) contained in the recovered solution obtained by electrodialysis was quantified by neutralization titration to determine the acid recovery rate. The results are shown in Table 1.
When the sulfuric acid concentration in the recovered solution is 6 mass %, the acid recovery rate is 80%.

<Cu ion removal rate>
The amount of copper ions contained in the recovered solution obtained by electrodialysis was quantified by ICP-MS (inductively coupled plasma mass spectrometry). The measurement device used was an AGILENT 8800 manufactured by Agilent Technologies. The results are shown in Table 1.
When the copper ion concentration in the recovered treated liquid is 500 ppm by mass, the Cu ion removal rate is 0%, and when the copper ion concentration in the recovered treated liquid is 0 ppm by mass, the Cu ion removal rate is 100%.

<Cleaning ability>
The substrates after the cleaning test were analyzed by SEM-EDX (scanning electron microscope-energy dispersive X-ray spectroscopy) and the cleaning properties were evaluated according to the following criteria. A Keyence VE-880 (magnification: 200 times, acceleration voltage: 5 kV) was used as the measuring device. The results are shown in Table 1.
[Evaluation Criteria]
○: Nitrogen and carbon derived from the rust inhibitor components are reduced, and oxygen derived from copper oxide is reduced.
×: No reduction in nitrogen or carbon derived from the rust inhibitor components was observed, or no reduction in oxygen derived from copper oxide was observed.

<Overall evaluation>
As a comprehensive evaluation, the reusability of the waste cleaning liquid was evaluated.
The overall evaluation was made based on the results of the acid recovery rate, the Cu ion rejection rate, and the cleaning ability, according to the following criteria. The results are shown in Table 1.
[Evaluation Criteria]
○: Waste cleaning liquid can be reused ×: Waste cleaning liquid cannot be reused

Test Example 1-2 Cleaning with Recycled Cleaning Solution A test was carried out in the same manner as in Test Example 1-1, except that the following concentration adjustment was carried out after the electrodialysis treatment and before the cleaning test.

<Density adjustment>
Before carrying out the cleaning test, sulfuric acid, which is an acid component, was added to the recovered treated liquid obtained by carrying out the electrodialysis treatment to adjust the concentration.
The concentration adjustment was performed so that the sulfuric acid concentration after the concentration adjustment was 6 mass %, which is the sulfuric acid concentration of the cleaning liquid.

The acid recovery rate was determined in the same manner as in Test Example 1-1, and the results are shown in Table 1.
The Cu ion removal rate was determined in the same manner as in Test Example 1-1. The results are shown in Table 1.
The cleaning properties were evaluated in the same manner as in Test Example 1-1, and the results are shown in Table 1.
A comprehensive evaluation was carried out in the same manner as in Test Example 1-1. The results are shown in Table 1.

Test Example 1-3 Cleaning Using Waste Cleaning Liquid A test was performed in the same manner as in Test Example 1-1, except that the electrodialysis treatment was not performed and the test waste liquid was used as a reused cleaning liquid in the cleaning test.
The cleaning properties were evaluated in the same manner as in Test Example 1-1, and the results are shown in Table 1.
A comprehensive evaluation was carried out in the same manner as in Test Example 1-1. The results are shown in Table 1.

[Test Example 2-1] Etching using recycled etching solution An etching test was carried out using a recycled etching solution. Specifically, the procedure was as follows.

<Etching Solution>
As an etching solution, TopRip manufactured by Okuno Pharmaceutical Co., Ltd. (aqueous solution with a nitric acid concentration of 25% by mass and a hydrogen peroxide concentration of 2% by mass) was used.

<Preparation of waste liquid for testing>
Copper and nickel were dissolved in the etching solution so that the metal ion concentration was 5000 ppm by mass (copper concentration: 2500 ppm by mass, and nickel concentration: 2500 ppm by mass) to obtain a test waste liquid.
The nickel is assumed to be a soluble component of the seed layer, and the copper is assumed to be a soluble component of the copper plating.

<Substrate for etching test>
As the etching test substrate, a circuit board having a Ni layer corresponding to a seed layer formed on the copper surface [a polyimide film (thickness 20 μm×10 cm×10 cm) on which 20 μm of copper was laminated] was used.

<Electrodialysis treatment>
The electrodialysis treatment was carried out using the following electrodialysis apparatus.
・Electrodialysis device: Micro Acilyzer S3 (manufactured by Astom)
・Cation exchange membrane: CKP-S (manufactured by Astom)
・Anion exchange membrane: ASE (manufactured by Astom)
Each ion exchange membrane was attached to a Micro Acilyzer S3 (manufactured by Astom), which is an apparatus for testing electrodialysis.
At 23° C., 500 mL of the test waste liquid was introduced into the micro-acid lyzer S3, and electrodialysis treatment was performed by applying a voltage of 15 V with a current of up to 2 A. The electrodialysis treatment was performed for about 2 hours while circulating the test waste liquid at a flow rate of about 5 L/min.
The recovered solution obtained by the electrodialysis treatment was used in the following etching test.

<Etching test>
500 mL of the recovered solution obtained by the electrodialysis treatment was placed in a 1000 mL beaker to prepare a reused etching solution. The etching test substrate was placed in the 1000 mL beaker, and the etching test substrate was etched at a temperature of 40° C. for 120 seconds.
During the etching, the reused etching solution was stirred using a magnetic stirrer.

The above test was evaluated as follows.
<Acid recovery rate>
The acid component (nitric acid) contained in the recovered solution obtained by electrodialysis was quantified by neutralization titration to determine the acid recovery rate. The results are shown in Table 2.
When the acid component (nitric acid) concentration in the recovered solution is 0 mass %, the acid recovery rate is 0%, and when the acid component (nitric acid) concentration in the recovered solution is 25 mass %, the acid recovery rate is 100%.

<Metal ion removal rate>
The amounts of copper ions and nickel ions contained in the recovered solution obtained by electrodialysis were quantified by ICP-MS (inductively coupled plasma mass spectrometry). The measurement device used was an AGILENT 8800 manufactured by Aglient Technologies. The results are shown in Table 2.
When the sum of the copper ion concentration and the nickel ion concentration in the recovered treatment liquid is 5,000 ppm by mass, the metal ion removal rate is 0%, and when the sum of the copper ion concentration and the nickel ion concentration in the recovered treatment liquid is 0 ppm by mass, the metal ion removal rate is 100%.

<Etching property>
The substrate after the etching test was analyzed by SEM-EDX (scanning electron microscope-energy dispersive X-ray spectroscopy) and the cleaning property was evaluated according to the following evaluation criteria. A Keyence VE-880 (magnification 200 times, acceleration voltage 5 kV) was used as the measuring device. The results are shown in Table 2.
[Evaluation Criteria]
◯: No seed layer components remain, and no discoloration of the substrate is observed.
×: Seed layer components remain, or the substrate is discolored.

<Overall evaluation>
As a comprehensive evaluation, the reusability of the waste etching solution was evaluated.
The overall evaluation was made based on the results of the acid recovery rate, the metal ion removal rate, and the etching property, and was made according to the following evaluation criteria. The results are shown in Table 2.
[Evaluation Criteria]
○: Etching solution waste liquid can be reused ×: Etching solution waste liquid cannot be reused

Test Example 2-2 Etching Using Recycled Etching Solution A test was carried out in the same manner as in Test Example 2-1, except that the following concentration adjustment was carried out after the electrodialysis treatment and before the etching test.

<Density adjustment>
Before the etching test, nitric acid and hydrogen peroxide were added to the recovered treated liquid obtained by the electrodialysis treatment to adjust the concentrations.
The concentration adjustment was performed so that the nitric acid concentration and hydrogen peroxide concentration were the same as those of the etching solution.

The acid recovery rate was determined in the same manner as in Test Example 2-1, and the results are shown in Table 2.
The metal ion removal rate was determined in the same manner as in Test Example 2-1. The results are shown in Table 2.
The etching property was evaluated in the same manner as in Test Example 2-1, and the results are shown in Table 2.
A comprehensive evaluation was carried out in the same manner as in Test Example 2-1. The results are shown in Table 2.

Test Example 2-3 Etching Using Waste Etching Solution A test was performed in the same manner as in Test Example 2-1, except that the electrodialysis treatment was not performed and the test waste solution was used as a reused etching solution in the etching test.
The etching property was evaluated in the same manner as in Test Example 2-1, and the results are shown in Table 2.
A comprehensive evaluation was carried out in the same manner as in Test Example 2-1. The results are shown in Table 2.

From the above, it was confirmed that by subjecting waste liquid from processing liquids for forming wiring circuits, such as cleaning liquids and etching liquids, to a recovery process, the processing liquids for forming wiring circuits can be reused.

1 1st A process 2 2nd A process 3 3rd A process 4 4th A process 5 5th A process 6 6th A process 11 cleaning liquid tank 12 cleaning device 13 waste liquid tank 14 recovery processing device 15 recovery processing liquid tank 16 analysis device 17 supply device 21 1st B process 22 2nd B process 23 3rd B process 31 rinsing liquid tank 32 rinsing device 33 waste liquid tank 34 recovery processing device 35 recovery processing liquid tank 36 analysis device 37 supply device 41 1st C process 42 2nd C process 43 3rd C process 51 etching liquid tank 52 etching device 53 waste liquid tank 54 recovery processing device 55 recovery processing liquid tank 56 analysis device 57 supply device 101 1st process 102 2nd process 103 3rd process 104 4th process 105 Fifth step 106 Sixth step 1001 Electrodialysis device 1002 Electrodialysis cell 1011 First cell 1012 Second cell 1013 Third cell 1021 Cation exchange membrane 1022 Anion exchange membrane 1031 First electrode 1032 Second electrode

Claims (8)

a first step of subjecting waste liquid of a wiring circuit forming treatment liquid used in a wiring circuit forming step to at least one of electrochemical treatment and dialysis treatment to obtain a recovered treatment liquid containing a treatment liquid component;
A second step of preparing a treatment liquid for forming a reused wiring circuit using the recovered treatment liquid;
A third step of forming a wiring circuit using the treatment liquid for forming a reused wiring circuit;
A method for manufacturing a wired circuit board, comprising: The method for producing a wired circuit board according to claim 1, wherein the recovery process is an electrodialysis process. The method for producing a wired circuit board according to claim 1, wherein the waste liquid, the recovery processing liquid, and the processing liquid for forming a recycled wired circuit contain an acid. The method for manufacturing a wired circuit board according to claim 1, wherein the treatment liquid for forming the wired circuit includes at least one of an acidic cleaning liquid for cleaning the surface in the process for forming the wired circuit and an acidic etching liquid for etching in the process for forming the wired circuit. The method for manufacturing a wired circuit board according to claim 1, wherein the waste liquid, the recovery processing liquid, and the processing liquid for forming a reused wired circuit contain alcohol and water. a fourth step of subjecting the waste liquid of the processing solution for forming the reused wiring circuit used in the third step to at least one of a recovery treatment of an electrochemical treatment and a dialysis treatment to obtain a second recovered processing solution containing a processing solution component;
a fifth step of preparing a second reuse wiring circuit forming treatment liquid using the second recovered treatment liquid;
A sixth step of forming a wiring circuit using the second reuse wiring circuit forming treatment liquid;
The method for producing the wired circuit board according to claim 1 , comprising: The second step is
A step of measuring the active ingredient in the recovered treatment liquid;
a step of adjusting the composition of the recovered treatment liquid to a predetermined composition using the measurement results of the active ingredient, thereby preparing the treatment liquid for forming a reused wiring circuit;
Including,
A method for producing the wired circuit board according to claim 1. The method for manufacturing a wired circuit board according to claim 1, wherein the first process, the second process, and the third process are carried out in one business establishment.

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