JP2012210598A - Method for producing valuable metal raw material for recycling from print wiring substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a recycling raw material of valuable metals such as high quality aluminum, gold, silver, copper by separating aluminum base substrate parts from print wiring boards having aluminum base substrates.SOLUTION: In the method for recovering the aluminum base substrates, an impact force of 190 N or more is applied to the print wiring substrates 1 in which electronic circuit is formed on the aluminum base substrates via insulating layers with a hammer, a blade, a chain 8, a wire or others. Thus, the aluminum base substrates can be easily peeled from the insulating layer by applying the impact to the print wiring substrates 1, further the valuable metals such as gold, silver, copper used for the printing wire boards can be separated to be used as the valuable metal raw materials for recycling.

Description

  The present invention relates to a method for producing a raw material for recycling valuable metals such as aluminum, gold, silver and copper from a printed wiring board provided with an aluminum base substrate.

A printed wiring board in which an electronic circuit such as a copper foil circuit is formed on an aluminum base substrate through an insulating layer has been developed. This is used for electronic control of an electric vehicle or the like, and is excellent in heat dissipation and heat resistance because aluminum is used for the base substrate.
As a printed wiring board provided with such an aluminum base substrate, there are those disclosed in Patent Documents 1 to 4 below.

JP-A-6-76631 JP-A-6-350213 JP 2000-340610 A JP 2007-27618 A

The electronic circuit provided on the aluminum base substrate includes gold (Au), silver (Ag), copper (Cu), and the like. In order to recycle aluminum, it is preferable that gold, silver, copper, etc. are not contained in aluminum, and it is desired that these can be separated and used as a raw material for recycling.
However, until now, in order to use expensive valuable metals such as gold, silver, and copper, which have a high value for aluminum, as raw materials for recycling, the printed wiring board is usually melted in a furnace in a copper smelting furnace. , And valuable metals such as silver and copper were produced as raw materials for recycling.
In this case, aluminum was not manufactured as a recycling raw material because it could not be separated as a high-value-added metal aluminum raw material simply because it was mixed into smelting slag and high-purity aluminum pieces could not be separated. It was.

Also, if you try to melt and recover only the aluminum substrate, it will contain gold, silver, copper, etc., so the quality of recycled aluminum will be inferior, and expensive gold, silver, copper will not be Loss that melts into aluminum occurs, resulting in a significant reduction in the recovery rate of each, and the need for a separate process for separating individual single metals from the alloy.
In addition, blasting and rolling of the entire substrate can be considered, but none of the target aluminum pieces are separated, and valuable metals such as aluminum, gold, silver, and copper cannot be suitably recovered. The practicable level was not reached.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing a valuable metal material for recycling such as high-grade aluminum, gold, silver and copper from a printed wiring board provided with an aluminum base substrate.

  The method for producing a valuable metal material for recycling according to the present invention is characterized in that an impact force of 190 N or more is applied to a printed wiring board in which an electronic circuit is formed on an aluminum base substrate via an insulating layer.

  By applying an impact force to the printed wiring board in this way, the aluminum base substrate and the insulating layer are peeled off, and further, gold, silver, copper, etc. of the circuit board are also separated. Recycling materials such as aluminum, gold, silver and copper can be manufactured.

It is the schematic sectional drawing which showed typically an example of the printed wiring board which can be used by this invention. It is the schematic sectional drawing which showed typically an example of the uniaxial crusher which can be used by this invention. It is the schematic perspective view which showed the state which is crushing the printed wiring board with the uniaxial crusher of FIG. An example of the biaxial crusher which can be used by this invention is shown, (A) is an apparatus external appearance, (B) is a cutting blade part. An example of the crushed printed wiring board is shown (A) is an aluminum base substrate portion, and (B) is an insulating layer portion. It is the schematic perspective view which showed an example of the color sorter | sorter which can classify the crushed printed wiring board.

  Hereinafter, an embodiment of a method for producing a valuable metal material for recycling according to the present invention will be described. The scope of the present invention is not limited to this embodiment.

  The manufacturing method of a valuable metal material for recycling according to an embodiment of the present invention is characterized in that an impact force of 190 N or more is applied to a printed wiring board in which an electronic circuit is formed on an aluminum base substrate via an insulating layer.

  As shown in FIG. 1, an example printed wiring board 1 that can be used in the present invention has an insulating layer 3 laminated on an aluminum base substrate 2 and an electronic circuit 4 formed thereon.

  The aluminum base substrate 2 is made of an aluminum plate, and the thickness of the aluminum plate is preferably more than 1.0 mm, more preferably 1.5 mm to 20.0 mm.

The insulating layer 3 is made of a resin substrate such as an epoxy resin, a glass epoxy resin, a phenol resin, or a polyimide resin, and the thickness is preferably 0.1 mm or more, more preferably 0.1 mm to 2.0 mm, particularly preferably. 0.2 mm to 1.0 mm. The insulating layer 3 can contain a heat radiation filler or the like.
The insulating layer 3 can be fixed by applying or sticking an adhesive or an adhesive sheet on the aluminum base substrate 2.
The aluminum base substrate 2 and the insulating layer 3 are preferably thicker. The reason is that when the thickness is reduced, even if an impact is applied, shear stress in the parallel direction is hardly generated at the interface between the aluminum substrate 2 and the insulating layer 3 or between the insulating layer 3 and the electronic circuit 4. This is because it becomes difficult to peel off.

  The electronic circuit 4 is made of a copper foil, a copper plate, or the like, and the thickness is preferably 5 μm to 1 mm, particularly preferably 10 μm to 100 μm. Electronic parts such as capacitors and chips may be mounted on the electronic circuit 4, and a solder resist may be applied. The surface of the copper foil or copper plate may be plated with gold to prevent corrosion.

When an impact of 190 N or more, preferably 160 N to 500 N is applied to the printed wiring board 1, the printed wiring board 1 becomes a crushed piece, and the aluminum base substrate 2 and the insulating layer 3 are easily peeled off. The circuit board 4 is easily separated.
In order to apply this impact, it is more preferable to apply a striking force only from one side of the printed wiring board 1. For example, any one of a hammer, a blade, a long chain, a wire and the like can be used.

For example, an apparatus 5 shown in FIGS. 2 and 3 can be used. This apparatus 5 is also called a uniaxial crusher, and a motor 7 is installed at the center of the bottom surface of a bottomed cylindrical container 6. One end of the chain 8 is bound so that the chain 8 can be rotated. By inserting the printed wiring board 1 into the apparatus 5, the printed wiring board 1 that has fallen and the rotating chain 8 collide, and an impact can be applied only from one side of the printed wiring board 1. The impact force can be changed by adjusting the rotational speed of the motor 7.
Moreover, you may use the biaxial crusher which a cutting blade part mutually meshes as shown in FIG. In this case, an impact is applied not only from one side of the printed wiring board 1 but also from both sides of the wiring board at the same time.
In addition, it is also possible to use a parts separator, hammer crusher, vertical crusher or the like that can obtain the impact force described above.
Moreover, an impact may be applied again to the crushed pieces that have been crushed by applying an impact force once, and separation is facilitated by repeatedly applying an impact twice or more.

  As shown in FIG. 5, the printed wiring board 1 subjected to the impact is crushed by the impact and the aluminum base substrate 2 and the insulating layer 3 and the insulating layer 3 and the circuit substrate 4 are easily separated. The aluminum can be recovered from the aluminum base substrate 2 with high quality, and valuable metals such as gold, silver and copper can be recovered from the circuit board 4 with high quality, and these can be used as raw materials for recycling. .

  In order to further reduce the cost of separation and increase the efficiency, it is preferable to use a color sorter after pulverization by the impact described above. For example, as shown in FIG. 6, this color sorter identifies a color by a color sensor by flowing a crushed piece of a printed wiring board 1 on a conveyor, and determines that the aluminum base substrate 2 is silver-white. Since the insulating layer 3 can be determined as green and can be skipped nearby, it can be easily and efficiently separated.

  Thus, by applying an impact to the printed wiring board 1, the insulating layer 3 can be peeled off from the aluminum base substrate 2, and high-quality aluminum can be used as a raw material for recycling. Further, the circuit board 4 can be separated from the insulating layer 3 and can be used as a raw material for recycling such as high quality gold, silver, and copper.

  Hereinafter, the Example of the manufacturing method of the valuable metal raw material for recycling of this invention is described. However, the scope of the present invention is not limited to this embodiment.

Example 1
The test was performed using 10 printed wiring boards of size L120 mm × W70 mm × T5 mm in which a predetermined circuit arrangement was formed. The thickness of the aluminum base substrate of this wiring board was 4 mm, the thickness of the insulating layer was 1 mm, the insulating layer was made of glass epoxy resin, and was affixed on the aluminum base substrate with an epoxy adhesive. The average weight of 10 printed wiring boards was 76.8 g. As a result of analysis, the metal component contained was 56.8 g of aluminum per board and 0.77 mg of gold and 6.68 g of copper.
Ten of these wiring boards were put into a uniaxial crusher (“Cross Shredder CFS-S1000” manufactured by Sato Tekko Co., Ltd.) as shown in FIGS. This impact force was calculated to be 255N.

  Thereafter, when the crushed printed wiring board was taken out from this apparatus, the aluminum base substrate and the insulating layer were cleanly separated and separated as shown in FIG. When the obtained crushed pieces were sorted by a color sorter (“Celestar TMS-6CM3” manufactured by Kitagawa Steel Works), 55.7 g of aluminum, 0.49 mg of gold, and 4 of copper that can be used as raw materials for recycling were used. 0.77 g was obtained, and the ratio of the recovered metal weight obtained only by fractionation after the treatment to the weight of the wiring board charged at the time of treatment was defined as the peel rate. As shown in Table 1, the peel rate was 97% by weight. Table 2 shows the quality and recovery rate of the metal obtained by the recovery. In addition, although the collection | recovery of gold | metal | money and copper other than aluminum was peeled from resin, since the adhesion | attachment of fine resin was seen, the purity after analysis is falling.

(Example 2)
The test was performed using 10 printed wiring boards of size L140 mm × W100 mm × T2.5 mm. The thickness of the aluminum base substrate of this wiring board was 2 mm, and the thickness of the insulating layer was 0.5 mm. The insulating layer was made of glass epoxy resin, and was affixed on the aluminum base substrate with an epoxy-based adhesive. The average weight was 119.0 g. As a result of analysis, the metal component contained was 75 g of aluminum, 2.38 mg of gold, and 40.1 g of copper per substrate.

Ten of the wiring boards were put into the same uniaxial crusher as in Example 1, and an impact was applied. The impact force was calculated to be 396 N.
Then, when the crushed printed wiring board was taken out from this apparatus and the aluminum base substrate and the insulating layer were manually peeled off, both can be easily peeled off. As shown in Table 1, the peeling rate is 90% by weight. Met. The quality and recovery rate of the metal obtained by the recovery were the values shown in Table 2 above.

(Example 3)
The test was performed using 10 printed wiring boards having a size of L110 mm × W100 mm × T2 mm. The thickness of the aluminum base substrate of this wiring board was 1.2 mm, and the thickness of the insulating layer was 0.1 mm. The insulating layer was made of glass epoxy resin, and was bonded onto the aluminum base substrate with an epoxy-based adhesive. The average weight was 65.1 g. As a result of analysis, the metal components contained were 58.6 g of aluminum, 2.0 mg of gold and 2.92 g of copper per substrate.

Ten of the wiring boards were put into the same uniaxial crusher as in Example 1, and an impact was applied. This impact force was calculated to be 220N.
Thereafter, the pulverized printed wiring board was taken out from the apparatus and the aluminum base substrate and the insulating layer were manually peeled off. Both of them could be easily peeled, and the peeling rate was 62% by weight as shown in Table 1. Met. The quality and recovery rate of the metal obtained by the recovery were the values shown in Table 2 above.

Example 4
A test was performed using 10 printed wiring boards identical to those in Example 1.
Ten of these wiring boards were put into a biaxial crusher (“Shredder UG165-20-240” manufactured by Ujiie Seisakusho) as shown in FIG. When this impact force was calculated, it was 198N.
Then, when the crushed printed wiring board was taken out from this apparatus, the aluminum base substrate and the insulating layer were peeled cleanly. The obtained crushed pieces were sorted by the same color sorter as in Example 1. As shown in Table 1, the peel rate was 95% by weight. The quality and recovery rate of the metal obtained by the recovery were the values shown in Table 2 above.

(Comparative Example 1)
The test was conducted using 10 printed wiring boards having a size of L120 mm × W66 mm × T1 mm. The thickness of the aluminum base substrate of this wiring board was 0.5 mm, and the thickness of the insulating layer was 0.05 mm. The insulating layer was made of glass epoxy resin, and was attached to the aluminum base substrate with an epoxy adhesive. The average weight was 16.4 g. As a result of analysis, the metal component contained was 56.8 g of aluminum, 0.77 mg of gold, and 6.68 g of copper per substrate.

Ten of the wiring boards were put into the same uniaxial crusher as in Example 1, and an impact was applied. This impact force was calculated to be 152N.
Thereafter, the pulverized printed wiring board was taken out from the apparatus and an attempt was made to manually peel off the aluminum base substrate and the insulating layer. However, both were fixed and could not be peeled off. The obtained product was a lump in which almost all the raw material was wrapped in aluminum, and the aluminum base substrate portion and the insulating layer could not be peeled off. The obtained lump was 81 wt% aluminum and 8 wt% copper.

(Comparative Example 2)
The test was performed using 10 printed wiring boards having the same substrate size L110 mm × W100 mm × T2 mm as in Example 2 and different aluminum layer and insulating layer thicknesses.
Ten of the wiring boards were put into the same biaxial crusher as in Example 4, and an impact was applied. This impact force was calculated to be 88N. In the obtained crushed pieces, the aluminum base substrate and the insulating layer were not peeled off. That is, there has not been obtained a crushed piece that can easily separate a target metal piece and other resins by simply picking up individual pieces such as aluminum pieces by hand sorting or a color sorter. As a result of analyzing the obtained crushed pieces, aluminum was 80 wt%.

(Comparative Example 3)
The test was performed using 10 printed wiring boards identical to those in Example 1. Ten of the wiring boards were melted with aluminum by a melting method to separate the deposit at the bottom of the crucible and the solid matter in the molten metal. The aluminum purity in the precipitate was 97.6 wt%, but only 62.8 wt% was recovered with respect to the aluminum weight in the raw material, and the copper purity of the lump obtained from the solid was 43.2 wt%. However, it cannot be used as it is as a recycled copper.

(result)
By applying an impact of 190 N or more to the wiring board, the aluminum base substrate can be easily peeled off, and the gold, silver, and copper of the circuit board can also be separated and used as a raw material for recycling. It was.
Even if an impact of less than 190 N was applied to the wiring board, it could not be peeled off, and valuable metals such as aluminum could not be separated from the resin substrate.
The crushed pieces obtained by applying an impact can be easily sorted by hand sorting or a color sorter, and the purity of valuable metal raw materials for recycling is as high as 90 wt% or more, and is a raw material. The recovery rate with respect to the metal content in the aluminum base substrate was also 90% by weight or more for aluminum, and the recovery rate was very high.

1 printed wiring board 2 aluminum base substrate 3 insulating layer 4 electronic circuit 5 device 6 container 7 motor 8 chain

Claims (8)

  A method for producing a valuable metal material for recycling by applying an impact force of 190 N or more to a printed wiring board in which an electronic circuit is formed on an aluminum base substrate through an insulating layer.   The manufacturing method according to claim 1, wherein the impact force is applied by any one of a hammer, a blade, a chain, and a wire.   The manufacturing method of Claim 1 or 2 which repeats the operation which applies the impact force of 190 N or more to a printed wiring board twice or more.   The manufacturing method according to claim 1, wherein the impact force is applied by a uniaxial crusher.   The manufacturing method in any one of Claims 1-4 which sorts the fragment of the printed wiring board obtained by the impact force with a color sorter.   The manufacturing method in any one of Claims 1-5 which have an insulating layer which is 0.1 mm or more in thickness.   The manufacturing method in any one of Claims 1-6 which have an aluminum layer exceeding thickness 1.0mm. The manufacturing method in any one of Claims 1-7 which obtains the valuable metal raw material for recycling of aluminum, copper, and gold | metal | money.

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