JP4808821B1 - Filtration filter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a filtration filter that does not require labor and time for forming an auxiliary film, can collect high-value copper powder as a valuable resource, and can be adopted regardless of the size of the apparatus.
A filtration filter of the present invention is a filtration filter for filtering a polishing waste liquid of a printed board, and includes an inner bag and an outer bag made of a mesh material. The mesh diameter of the inner bag is made larger than the mesh diameter of the outer bag. Both the inner bag and the outer bag are flexible. The inner bag and the outer bag have a vertically long bag shape, and an opening is provided on the lower end side so that the collected material can be taken out from the opening. A winding portion for sealing the opening may be provided on the opening side. An inlet is provided on the upper end side of the inner bag and the outer bag. The inner bag and the outer bag can be connected to form a unit.
[Selection] Figure 1

Description

The present invention relates to a filtration filter, and more specifically, filtration used for filtration of waste liquid (hereinafter referred to as “polishing waste liquid”) generated during polishing of a printed circuit board and the like (hereinafter collectively referred to as “substrate”). Regarding filters.

  The substrate includes circuit wiring made of metal, particularly copper. The substrate is polished (mainly buffed) to remove oxides, burrs, whiskers, etc. adhering to it, to make the thickness of circuit wiring uniform, or to smooth the surface of the substrate. . For the buffing of the substrate, for example, a circulation type polishing system (hereinafter referred to as “circulation type polishing system”) as shown in FIG. 6 is used. In addition, there is a method as shown in Patent Document 1.

  The circulating polishing system shown in FIG. 6 includes a polishing chamber C for polishing a substrate, a clean tank A for storing cleaning water (polishing liquid) for cleaning the substrate, a dirty tank D for storing polishing waste liquid, and a polishing A filtration tower (tank) E for filtering the waste liquid, a filtration filter X set in the filtration tower E, and a filtered water tank F for storing filtered water (liquid) that has passed through the filtration filter X are provided. The circulating polishing system operates as follows.

The cleaning water stored in the clean tank A is pumped up by the first pump P1, and the pumped cleaning water is supplied via a cleaning water supply pipe G to a substrate (not shown) to be polished in the polishing chamber C. The The cleaning water (polishing waste liquid) used for polishing is sent into the dirty tank D through the polishing waste liquid path H. The polishing waste liquid sent into the dirty tank D passes through the transfer pipe I, is sent to the waste liquid introduction pipe J by the second pump P2, and is introduced into the filtration tower E from the front end side of the waste liquid introduction pipe J. The introduced polishing waste liquid passes through the bag-shaped filtration filter X and is filtered, and the filtrate is stored in the filtrate tank F. The filtered water stored in the filtered water tank F is sent to the clean tank A through the return path K and is supplied (circulated) to the polishing substrate in the polishing chamber C again. The circulation type polishing system is provided with a valve for dehydration operation (not shown) so that compressed air from a compressor or the like can be sent by operating the valve. The filtration filter X is dewatered by compressed air by a dehydrating compressor (not shown) after polishing, and foreign matters (removed pieces such as oxides, burrs, and whiskers, buffs, copper powder, etc.) attached to the filtration filter X are collected. Is done. The collected foreign matter, particularly copper powder, is reused as a valuable resource.

  A mesh material is generally used for the filtration filter. The filtration filter made of a mesh material has a problem in that foreign matter is clogged in the mesh of the mesh as filtration is repeated, and the filtration accuracy is lowered. Such a problem can be solved by exchanging the filtration filter X. However, for exchanging the filtration filter X, the filtration system must be suspended (pause) to interrupt the filtration operation, and the work efficiency is lowered. In addition, the replacement work takes time and labor, and the replacement filtration filter X is required, resulting in high costs.

  In order to solve the clogging, in recent years, a liquid (auxiliary liquid) in which an auxiliary agent such as diatomaceous earth is dissolved is put in a mesh filter filter, and an auxiliary film is attached to the inner surface of the filter filter. Thus, a technique for preventing clogging of the mesh material has been proposed.

JP 2005-319463 A

However, in order to form the auxiliary layer on the inner surface of the filtration filter, it is necessary to 30 to 40 minutes about rotating putting aid solution into the filtration filter (idling), the molding auxiliaries film It takes time. During this time, the polishing waste liquid cannot be filtered, so that there is a problem that workability is poor. Moreover, since the auxiliary | assistant is mixed in the copper powder collect | recovered after filtration, the value as a valuable resource of copper powder was low, and there also existed a difficulty that the use of a reuse was restricted. Although it is conceivable to separate the copper powder from the auxiliary agent after the recovery, considering the labor and time required for the work, the cost increases and it is not realistic. In addition, since the auxiliary film is made difficult to be clogged, it becomes difficult for the polishing waste liquid to pass through and the processing amount per unit time is reduced. There is also a problem that the working environment is deteriorated due to scattering of the auxiliary agent.

  The filter used in the apparatus of Patent Document 1 can solve the above-mentioned problems, but the filter used in this apparatus must take out the filter from the filtration tower each time in order to recover the separated metal powder. There is annoyance. In addition, a certain effect can be obtained as long as it is applied to a small device that can be easily taken out by hand as in Patent Document 1, but for example, a large device that is as tall as a person's height is patented. It is difficult to employ a filter having a structure as described in Document 1.

Solving problems of the present invention, hardly clogged even without forming the auxiliary film, filtration efficiency even Filtration accuracy without reducing, even despite the time effort of forming auxiliaries film, foreign matter It is an object of the present invention to provide a filtration filter that can collect copper powder with little contamination, easily collect copper powder, and can be employed regardless of the size of the filtration device.

The filtration filter of the present invention, a polishing waste liquid generated when the substrate is polished by filtration, at least in Filtration filter that captures copper powder contained in the polishing waste, the filtration filter is the inner filter and the outer filter two inside and outside Polishing waste liquid for supplying polishing waste liquid into the inner filter on the upper end side of either or both of the inner filter and the outer filter. An introduction port is formed, and lower end openings for taking out foreign matters captured by the respective filters are formed on the lower end sides of the inner filter and the outer filter, and the lower end opening can be opened and closed. the polishing waste is turned with the flexibility to expand its water pressure, the inner filter and the outer filter are made of mesh material, the mesh size of said filter the outer At least copper powder and it than the small size foreign matter polishing liquid waste flowing into the inner the filter size rather and than the mesh size of the filter can flow out into the outer filter through, be a size that can be captured large foreign substances than those The mesh diameter of the outer filter is set to a size capable of capturing at least copper powder and foreign matters having a larger size in the polishing waste liquid flowing out from the inner filter.

The filtration filter is provided with a mounting portion that can be attached to the filtration tower on either or either of the inner filter and the outer filter, or on the lower end opening side of either or both of the inner filter and the outer filter. It is also possible to provide an impermeable winding part that does not pass through. In the filtration filter, the lower end openings of both the inner filter and the outer filter can be opened and closed. The filtration filter may be a filter in which a part of the inner filter and the outer filter are connected.

The filtration filter may be provided with a liquid-impervious portion where the polishing waste liquid does not leak over the inner filter and the outer filter.

The filtration filter of the present invention has the following effects.
(1) Two layers of an inner filter and an outer filter are provided, and the inner filter functions in the same manner as a conventional auxiliary film, so that it is not necessary to form an auxiliary film. For this reason, conventionally, the time (30 to 40 minutes) required for forming the auxiliary film can be used for the filtration work, and the workability is improved.
(2) It is not necessary to use an auxiliary agent, which contributes to cost reduction. In addition, since the auxiliary agent is not used, the burden on the filter is small, and the service life is extended, which is economical.
(3) Since no auxiliary is used, high-purity copper powder can be recovered, which contributes to the effective reuse of valuable resources.
(4) in the filter and the outer filter are mesh material, because the mesh size of the inner filter is made larger than the mesh size of the outer filter, can relatively recover large foreign matter within the filter, fine outside filter Foreign matter can be collected.
(5) Since the inner filter and the outer filter have flexibility, they can be rolled or folded compactly. For this reason, storage and transportation of a filtration filter, attachment to a filtration tower, etc. can be performed easily.
(6) the inner filter and the outer filter of the filtration filter is a bag-like or tubular, the lower end opening at its lower side is provided, it is possible to take out the recovered product with only the opening and closing of the lower end opening, the work Excellent in properties. In some cases, the recovered material can be taken out while being suspended from the filter tower.
(7) in the filter and the lower end opening side of the outer filter, the case of providing a sealing portion for sealing (winding portion) of the open mouth, there is no fear that foreign substances and waste leakage during filtration.
(8) A polishing waste liquid inlet is provided at the upper end of either or both of the inner filter and the outer filter so that the polishing waste liquid can be introduced from above, so convection occurs due to the water flow of the polishing waste liquid inside the filter. It's easy to do. For this reason, foreign matters are dispersed without concentrating on one place in the filtration filter , and clogging is less likely to occur.
(9) When a part of the inner filter and the outer filter are connected to form a unit, the structure is simplified and the manufacturing cost can be reduced. When a part of the inner filter and the outer filter are connected (made common), the mounting work to the filtration tower becomes easy.

Explanatory drawing of a notch which shows an example of the filtration filter of this invention. The perspective view which shows an example at the time of attaching the filtration filter of this invention to the filtration tower. The enlarged view of the upper end side and lower end side of the filtration filter of this invention. There is shown a connection example of the inner filter and outer filter, (a) shows the sectional view in the case of connecting the shorter inner filter than the outer filter on the inner peripheral surface of the opaque liquid portion of the outer filter, (b) is sectional view of a concatenation of shorter outer filter from the inner filter to the outer peripheral surface of the opaque liquid portion of the inner filter. Explanatory drawing which shows the filtration state of an inner filter and an outer filter . 1 is a schematic view of a circulating polishing system that uses the filtration filter of the present invention.

(Embodiment 1)
An example of an embodiment of the filtration filter of the present invention will be described with reference to the drawings. As an example, the filtration filter 1 shown in FIG. 1 filters the polishing waste liquid of the printed circuit board, and is used by being suspended in the filtration tower E of the circulation type polishing system shown in FIG. The filtration filter 1 shown in FIG. 1 has two layers of an inner filter 2 and an outer filter 3, and the inner filter 2 has a similar shape smaller than that of the outer filter 3. At the lower ends of the inner filter 2 and the outer filter 3, lower end openings 2a and 3a (FIG. 3) for taking out the captured foreign matter are provided.

The inner filter 2 on the top of the body portion 5 made of a mesh material, impermeable liquid portion 6 made of liquid-impervious material is provided due to sewing, the bottom of the body 5, the liquid is not transmitted FuToruzai The made-up winding part 7 is provided by sewing or the like. The outer filter 3 on the top of the body portion 8 made of a mesh material, impermeable liquid portion 9 made of FuToruzai is provided due sewing, the bottom of the body portion 8, FuToruzai made up portion 10 Is provided by sewing. These impermeable liquid portion 6 and 9, by providing the winding portion 7 and 10, the polishing waste liquid introduced into the filter in 2 their locations (liquid-impervious portions 6,9, up portion 7 and 10) to the outside from It is designed not to leak.

A reinforcing material 11 is provided on the upper surfaces of the inner filter 2 and the outer filter 3 (the reinforcing material of the inner filter 2 is not shown). The impermeable liquid portion 6 and 9, the winding portion 7 and 10 may be used other materials (material other than mesh). The reinforcing material 11 of the inner filter 2 and the outer filter 3 has a horizontally long outer shape, and a polishing waste liquid introduction port 13 through which the tip of the waste liquid introduction pipe J (FIG. 6) can be introduced into the inner filter 2 is opened at the center thereof. In addition, locking holes 14 (attachment portions) are opened on both sides of the polishing waste liquid inlet 13. The tip of a waste liquid introduction pipe J (FIG. 2) can be inserted into the polishing waste liquid inlet 13. A locking tool L (FIG. 2) is locked in the locking hole 14 so that the inner filter 2 and the outer filter 3 can be suspended from the filtration tower E (FIG. 6) as shown in FIG. . The reinforcing material 11 can be made of various materials, for example, a felt material excellent in durability and flexibility. For example, the impervious material may be a woven fabric coated with rubber or resin or laminated.

The opening diameter (hereinafter referred to as “mesh diameter”) of the body part 5 of the inner filter 2 and the body part 8 of the outer filter 3 can be selected arbitrarily according to the size of the foreign matter to be collected. Mesh diameter of the body portion 5 of the inner filter 2 is larger than the mesh size of the body portion 8 of the outer filter 3, a relatively large foreign matter body part 5 of the inner filter 2 catches (coarse filtration), the outer filter 3 The body portion 8 can capture (finely filter) fine foreign matters (for example, copper powder contained in the polishing waste liquid) . The body part 5 of the inner filter 2 can be a mesh of about 50 to 100 μm, and the body part 8 of the outer filter 3 can be a mesh of about 20 to 30 μm. A screen mesh having a mesh diameter of about 90 μm can be used for the inner filter 2, and a monofilament having a mesh diameter of about 25 μm can be used for the outer filter 3.

The inner filter 2 and the outer filter 3 have flexibility, and when liquid (polishing waste liquid) or gas is supplied into the inner filter 2, the inner filter 2 and the outer filter 3 expand due to the water pressure of the polishing waste liquid, and the liquid (polishing waste liquid) or gas inside When discharged, it deforms into a flat shape. The inner filter 2 and the outer filter 3 can be rounded or folded in a flat state.

Lower end opening 2a of the filter 2 can be sealed (closed) by winding up the winding portion 7 provided at the lower side of the inner filter 2 upwardly, the lower end opening 3a of the outer filter 3 external filter 3 can be sealed (closed) by hoisting the hoisting part 10 provided in the lower end opening 3a. A fastener 4 (FIG. 3) such as a surface fastener, a button, and a zipper may be provided on the periphery of the lower end openings 2 a and 3 a so as to be closed. As shown in FIG. 2, the tip of the waste liquid introduction pipe J is inserted into the polishing waste liquid introduction port 13, the locking tool L is locked in the locking hole 14, and the inner filter 2 and the outer filter 3 are suspended. When the locking tool L inserted into the locking hole 14 is tightened, the outer filter 3 is fixed in the filtration tower E (FIG. 2).

(Other example 1 of filtration filter)
Other examples of the filter of the present invention are shown in FIGS. 4 (a) and 4 (b). The filter 1 of FIG. 4A also has a two-layer structure of an inner filter 2 and an outer filter 3, and the structure, material, etc. are the same as those shown in FIG. The difference is, the shorter inner filter 2 in length than the interior of the outer filter 3 is housed and arranged, it is mounted to the upper end portion 12 of the inner filter 2 to the impermeable liquid portion 9 of the outer filter 3. The attachment means can be various means such as adhesion and sewing.

The filtration filter 1 shown in FIG. 4B also has a two-layer structure of an inner filter 2 and an outer filter 3, and the structure, material, etc. are the same as those shown in FIG. The difference is covered with a short outer filter 3 lengths than the inner filter 2 outside, is mounted to the upper end portion 15 of the outer filter 3 to the impermeable liquid portion 9 of the inner filter 2. The attachment means can be various means such as adhesion and sewing.

(Other example 2 of filtration filter)
Although the filtration filter 1 described above has been described as an example of a two-layer filter comprising an inner filter 2 and an outer filter 3, the filtration filter 1 of the present invention may have three or more layers. Also in this case, it is preferable that the mesh diameter of the filter disposed on the inner side is larger than the mesh diameter of the filter disposed on the outer side so that the coarse foreign matters are sequentially captured by the fine foreign matters. Inner filter 2, the structure of the outer filter 3, the shape, the material, etc. If the solution to issues of the present invention, may be other than shown.

(Example of use)
The filtration filter 1 of the present invention is used, for example, suspended in a filtration tower E of a circulating polishing system shown in FIG. 6 as shown in FIG. In order to install the filtration filter 1 in the filtration tower E as shown in FIG. The opening / closing door N attached to the main body M of the filtration tower E by a hinge is opened, and the filtration filter 1 is disposed in the main body M. The tip of the waste liquid introduction pipe J is inserted into the polishing waste liquid inlet 13 (FIG. 1) formed in the reinforcing material 11 of the filtration filter 1, and the locking tool L is formed in the reinforcing hole 11 (FIG. 1). When it is inserted into 1) and the locking tool L is tightened, the outer filter 3 is fixed in a state of being suspended in the filtration tower E. At this time, the winding parts 7 and 10 on the lower end side of the inner filter 2 and the outer filter 3 are wound upward, and the door N is closed in this state and the door N is locked by the door fixing unit O. Thereby, the winding-up parts 7 and 10 are fixed to the winding-up state, and the filtration filter 1 is installed in the filtration tower E.

In this state, the circulating polishing system is operated to circulate cleaning water and polishing waste liquid. The polishing waste is introduced into the filtration filter in one of the filtration column E from the waste liquid introduction pipe J, as shown in FIG. 5, larger foreign matter Q such buff dregs are captured by the inner filter 2, copper outside the filter 3 Fine foreign matter R such as powder is captured. When the polishing is performed for a predetermined time and the foreign matter is continuously collected during that time, the second pump P2 is stopped and the supply of the polishing waste liquid into the filter 1 is stopped. Thereafter, the filtration filter 1 suspended in the filtration tower E is dehydrated, the winding portions 7 and 10 on the lower end side of the filtration filter 1 are lowered downward, and the openings 2a and 3a are opened. Collect the trapped foreign matter.

  The copper powder recovered by the conventional method contains an auxiliary agent, and the ratio of the copper powder is only about 25%. On the other hand, when the filtration filter of the present invention was used, about 90% or more of the collected foreign matter was copper powder, and it was confirmed that there was a big difference between the two.

1 the filtration filter 2 in the filter 2a lower end opening 3 outer filter 3a bottom opening 4 fastener 5 fuselage section 6 impermeable liquid portion 7 up portion 8 the body portion 9 impermeable liquid portion 10 up portion 11 reinforcement 12 upper end 13 polished Waste liquid inlet 14 Locking hole (mounting part)
15 Upper end A Clean tank C Polishing chamber D Dirty tank E Filtration tower F Filtration water tank G Washing water supply pipe H Polishing waste liquid path I Transfer pipe J Waste liquid introduction pipe K Return path L Locking tool M Main body N Open / close door O Door fixing Unit P1 First pump P2 Second pump Q Large foreign matter R Fine foreign matter X Filtration filter

Claims (5)

The polishing liquid waste generated during substrate polishing filtration, at least in Filtration filter that captures copper powder contained in the polishing waste, the filtration filter is the inner filter and the outer filter provided in two layers inside and outside, the inner filter Each of the outer filter and the outer filter has a bag shape or a cylindrical shape, and a polishing waste liquid inlet for supplying polishing waste liquid into the inner filter is formed on the upper end side of either or both of the inner filter and the outer filter. When a lower end opening for removing foreign matter captured by the respective filters is formed on the lower end side of the filter and the outer filter, the lower end opening can be opened and closed, and when the polishing waste liquid is put into the inner filter and the outer filter comprising a flexible to be expanded by the water pressure, the inner filter and the outer filter are made of mesh material, the mesh size of said filter than the mesh size of the outer filter At least copper powder and it than the small size foreign matter in the polishing liquid waste which has flowed into the inner the filter can rather and can flow out into the outer filter through a size that can capture large foreign substances than those of the outer filter mesh diameter Is a size capable of trapping at least copper powder and larger foreign substances in the polishing waste liquid flowing out from the inner filter. In the filtration filter according to claim 1, wherein the inner filter and both or either one of the outer filter, the filtration filter which is characterized in that a mounting portion for attachment to the filtration tower. In the filtration filter according to claim 1 or claim 2 wherein, characterized in that on both or either of the lower end opening side of the inner filter and the outer filter, impervious over of winding portions polishing waste does not pass is provided Filter filter. The filtration filter according to any one of claims 1 to 3, wherein a part of the inner filter and a part of the outer filter are connected. 5. The filtration filter according to claim 1, wherein an impervious portion that does not leak polishing waste liquid is provided above the inner filter and the outer filter. 6.

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