Cleaning device

Abstract

To provide a cleaning deice that can effectively remove foreign matter even from an object having a via hole in its surface.SOLUTION: A cleaning device removes foreign matter adhering to at least one surface of a plate-shaped or film-shaped object that has a bottomed via hole therein. The cleaning device has a roller-shaped cleaning brush which is rotatably disposed about an axis of rotation perpendicular to the conveying direction of the object and parallel to an object surface and is brought into contact with the object surface. The cleaning brush has a columnar core and a brush section formed by implanting a plurality of bristles on the peripheral surface of the core. The ratio of the diameter of the bristle to the diameter of the via hole is 1 / 3 or less. An amount of pressure welding of the cleaning brush at a point of contact with the via hole bottom section of the object is 0.2 mm or more and 0.7 mm or less.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a cleaning device.

Background Art

[0002] In recent years, cleaning devices have been developed for removing foreign substances such as dust adhering to the surfaces of objects such as glass substrates of flat panel displays (FPDs), printed boards on which electronic components are mounted, resin thin plates, and film materials.

[0003] As such a cleaning device, a cleaning device has been proposed that includes a cleaning brush that rotates in a direction opposite to the conveyance direction of an object and contacts the surface of the object, and a cleaning roller that rotates in a direction forward with respect to the conveyance direction of the object and contacts the surface of the object (see Japanese Patent Application Laid-Open No. 2016-215155).

[0004] By using this cleaning device, relatively large foreign substances of millimeter size can be effectively scraped up by the cleaning brush, and mainly fine foreign substances can be removed by the cleaning roller, so that foreign substances of different sizes can be effectively removed.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] The above-described conventional cleaning device can effectively remove foreign substances adhering to an object having a relatively flat surface. However, when the object is, for example, a substrate, bottomed via holes are often provided on its surface, and there are depressions. Foreign substances located in the shade of such via holes tend to be difficult to remove.

[0007] The present invention has been made in view of such inconveniences, and an object thereof is to provide a cleaning device capable of effectively removing foreign matter even from an object having via holes on its surface.

Means for Solving the Problems

[0008] A cleaning device according to an embodiment of the present invention is a cleaning device for removing foreign matter adhering to at least one surface of a plate-shaped or film-shaped object having bottomed via holes, and is disposed rotatably about a rotation axis perpendicular to the conveyance direction of the object and parallel to the object surface, and includes a roller-shaped cleaning brush that contacts the object surface. The cleaning brush has a columnar core metal and a brush portion formed by implanting a plurality of hairs on the peripheral surface of the core metal. The ratio of the diameter of the hairs to the diameter of the via holes is 1 / 3 or less, and the amount of pressure contact of the cleaning brush at the contact portion with the bottom of the via holes of the object is 0.2 mm or more and 0.7 mm or less.

Effects of the Invention

[0009] The cleaning device of the present invention can effectively remove foreign matter even from an object having via holes on its surface.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Modes for Carrying Out the Invention

[0011] [Description of Embodiments of the Present Invention] First, embodiments of the present invention will be listed and described.

[0012] (1) The inventors of the present invention found that when a cleaning brush needs to scrape out foreign matter inside a via hole and meets certain requirements, the foreign matter removal progresses dramatically, and thus completed the present invention. That is, a cleaning device according to an embodiment of the present invention is a cleaning device for removing foreign matter adhering to at least one surface of a plate-shaped or film-shaped object having a bottomed via hole, and is rotatably disposed about a rotation axis perpendicular to the conveyance direction of the object and parallel to the object surface, and includes a roller-shaped cleaning brush that contacts the object surface. The cleaning brush has a columnar core metal and a brush portion formed by implanting a plurality of hairs on the peripheral surface of the core metal. The ratio of the diameter of the hair to the diameter of the via hole is 1 / 3 or less, and the amount of pressure contact of the cleaning brush at the contact portion with the bottom of the via hole of the object is 0.2 mm or more and 0.7 mm or less.

[0013] In the cleaning device, since the ratio of the diameter of the hair to the diameter of the via hole is set to be equal to or less than the upper limit, the tip of the hair can enter the via hole. Further, since the amount of pressure contact of the cleaning brush at the contact portion with the bottom of the via hole is within the above range, the tip of the hair can surely contact the foreign matter and scrape out the foreign matter from the via hole.

[0014] (2) In the cleaning device of (1) above, a cleaning roller is provided which is located on the downstream side of the cleaning brush, has a rotation axis arranged parallel to the cleaning brush, and contacts the surface of the object while rotating. The rotation direction of the cleaning brush at the contact portion with the surface of the object is opposite to the conveying direction, and the rotation direction of the cleaning roller at the contact portion with the surface of the object is in the same direction as the conveying direction. By using the cleaning roller in combination in this way and setting the rotation directions of both as described above, foreign matter can be efficiently scraped out of the via hole by the cleaning brush, and the scraped foreign matter can be more reliably collected by the cleaning roller located on the downstream side.

[0015] (3) In the cleaning device of (1) or (2) above, it is preferable that the cleaning brush contacts the one surface in a charged state. By charging the cleaning brush in this way, foreign matter can be efficiently removed by electrostatic adsorption force.

[0016] Here, "parallel" means a concept that includes not only being exactly parallel but also being substantially parallel, in other words, the included angle is within ±10°, preferably within ±5°. Also, "perpendicular" means a concept that includes not only the angle being exactly 90° but also being substantially perpendicular, in other words, the included angle is within 90° ± 10°, preferably within 90° ± 5°.

[0017] Also, "the amount of pressure contact" means the difference between the distance between the surface of the mandrel and the object at the contact portion between the cleaning brush and the object and the length of the bristles of the brush portion.

[0018] Regarding "the contact portion with the bottom of the via hole", when the bottom of the via hole is not composed of a plane parallel to the surface of the object, it means the deepest part with respect to the surface of the object. Also, "the diameter of the via hole" means the diameter of the hole on the surface of the object, and when the hole on the surface of the object is not in an edge shape, it means the diameter of the smallest circle that can include the hole.

[0019] [Details of Embodiments of the Present Invention] A cleaning device according to an embodiment of the present invention will be described with reference to the drawings.

[0020] 〔Cleaning Device〕 The cleaning device 1 shown in FIGS. 1 and 2 is a cleaning device that removes foreign matter adhering to one surface of an object S. The cleaning device 1 includes a cleaning brush 10, a cleaning roller 20, and a transport mechanism 30, and is arranged in the order of the cleaning brush 10 and the cleaning roller 20 from the upstream side in the transport direction D (the direction of the white arrow in FIGS. 1 and 2).

[0021] <Object> The object S to be cleaned by the cleaning device 1 is plate-shaped or film-shaped, and examples of the object S include a glass substrate of an FPD (Flat Panel Display), a printed circuit board on which electronic components are mounted, a resin thin plate, a film material, and the like.

[0022] The object S has a bottomed via hole S1 on the one surface. The shape, depth, etc. of the via hole S1 are not particularly limited, but the shape of the via hole S1 is preferably columnar, prismatic, or frustoconical or pyramidal frustum-shaped with a small area on the bottom side of the via hole S1.

[0023] Examples of the dimensions of the via hole S1 include those having a diameter of 10 μm or more and 0.6 mm or less, a depth of 1 μm or more and 3 mm or less, and a ratio of the depth to the diameter of 5.0 or less.

[0024] When the shape of the via hole S1 is columnar, prismatic, or frustoconical or pyramidal frustum-shaped with a small area on the bottom side of the via hole S1, the via hole S1 is composed of a bottom surface and a side surface, and the bottom surface is parallel to one surface of the object S. The object S may have a plurality of via holes S1. In this case, the shapes and dimensions of the plurality of via holes S1 do not have to be the same, but usually at least the depths are the same.

[0025] The average thickness of the object S is not particularly limited. However, as the lower limit of the average thickness of the object S, for example, 10 μm is preferable, and 30 μm is more preferable. On the other hand, the upper limit of the average thickness of the object S depends on the surface area of the object S. For example, 5 cm is preferable, and 3 cm is more preferable. If the average thickness of the object S is less than the above lower limit or exceeds the above upper limit, it may be difficult to transport the object S. Note that "average" refers to the average value of the amounts measured at any 10 locations. The same applies throughout this specification below.

[0026] The lower limit of the transport speed of the object S is not particularly limited. For example, 5 m / min is preferable, and 10 m / min is more preferable. On the other hand, as the upper limit of the transport speed of the object S, 30 m / min is preferable, and 20 m / min is more preferable. If the transport speed of the object S is less than the above lower limit, the time required for foreign matter removal may become long, and the foreign matter removal efficiency may decrease. Conversely, if the transport speed of the object S exceeds the above upper limit, there is a possibility that the foreign matter on the surface of the object S cannot be sufficiently adsorbed by the cleaning roller 20.

[0027] Foreign matter is attached to one surface of the object S before cleaning by the cleaning device 1. The foreign matter attached to the object S is often charged. Hereinafter, the case where the foreign matter is positively charged will be taken as an example for continued explanation, but the foreign matter may be negatively charged. If the foreign matter is negatively charged, the positive and negative of the following charging are reversed. Also, even if the foreign matter is not charged, the effects of the present invention can be obtained.

[0028] <Cleaning brush> The cleaning brush 10 is in the shape of a roller and has a columnar mandrel 11 and a brush portion 12 formed by implanting a plurality of bristles 12a on the peripheral surface of the mandrel 11. The cleaning brush 10 is rotatably disposed about a rotation axis perpendicular to the transport direction D of the object S and parallel to the surface of the object S, and contacts the surface of the object S. At this time, when passing through the via hole S1, the cleaning brush 10 is configured such that the tip of the brush portion 12 (the tip of the bristle 12a) contacts the bottom surface of the via hole S1.

[0029] The rotation direction of the cleaning brush 10 at the contact portion with the surface of the object S is opposite to the conveyance direction D. In other words, the cleaning brush 10 is rotationally driven in the reverse direction by the driving device. By rotating the cleaning brush 10 in this reverse direction, the relative peripheral speed with respect to the object S can be increased, and foreign matter can be efficiently scraped out from the via hole S1 with the cleaning brush 10.

[0030] As the bristles 12a forming the brush portion 12, those to which foreign matter is likely to physically adhere are preferable, and examples thereof include fibers made of synthetic resin. Further, as the bristles 12a forming the brush portion 12, those capable of being charged with an electric charge for adsorbing foreign matter adhering to the surface of the object S by the force of an electric field are preferable, and for example, fibers made of synthetic resin containing a conductive material such as carbon black, carbon fiber, metal powder, and metal whiskers can be preferably used.

[0031] The cross-sectional shape of the bristles 12a of the brush portion 12 is not particularly limited, and as the brush portion 12, for example, those having a circular cross-sectional shape, an elliptical cross-sectional shape, a star-shaped cross-sectional shape, etc. of the bristles 12a can be used. Further, the outer shape of the bristles 12a of the brush portion 12 is not particularly limited, and as the bristles 12a of the brush portion 12, for example, those having an outer shape such as a linear shape, a wavy curve shape, and a shape formed by combining a curve and a straight line can be used. Note that the larger the surface area of the bristles 12a of the brush portion 12, the easier it is to adsorb foreign matter. Therefore, as the bristles 12a forming the brush portion 12, for example, those having a star-shaped cross-sectional shape can be preferably used.

[0032] The lower limit of the length of the bristles 12a is preferably 2 mm, more preferably 3 mm. On the other hand, the upper limit of the length of the bristles 12a is preferably 8 mm, more preferably 6 mm. If the length of the bristles 12a is less than the above lower limit, the bristles 12a are difficult to bend, and there is a risk that foreign matter accumulated inside the via hole S1 cannot be sufficiently scraped out. Conversely, if the length of the bristles 12a exceeds the above upper limit, the bristles 12a are bent too much, and the force for lifting foreign matter from inside the via hole S1 is insufficient, and there is a risk that foreign matter accumulated inside the via hole S1 cannot be sufficiently scraped out.

[0033] As the lower limit of the diameter of the hair 12a, 10 μm is preferable, and 15 μm is more preferable. On the other hand, as the upper limit of the diameter of the hair 12a, 100 μm is preferable, and 75 μm is more preferable. If the diameter of the hair 12a is less than the above lower limit, the rigidity of the hair 12a may be insufficient, and there is a risk that foreign matter accumulated inside the via hole S1 cannot be sufficiently scraped out. Conversely, if the diameter of the hair 12a exceeds the above upper limit, the tip of the hair 12a may not sufficiently enter the bottom surface of the via hole S1, and there is a risk that foreign matter accumulated inside the via hole S1 cannot be sufficiently removed.

[0034] The upper limit of the ratio of the diameter of the hair 12a to the diameter of the via hole S1 is 1 / 3, and 3 / 10 is more preferable. If the above ratio exceeds the above upper limit, the tip of the hair 12a may not sufficiently enter the bottom surface of the via hole S1, and there is a risk that foreign matter accumulated inside the via hole S1 cannot be sufficiently removed.

[0035] The lower limit of the amount of pressure contact of the cleaning brush 10 at the setting portion with the bottom of the via hole S1 of the object S is 0.2 mm, and 0.4 mm is more preferable. On the other hand, the upper limit of the above pressure contact amount is 0.7 mm, and 0.6 mm is more preferable. If the above pressure contact amount is less than the above lower limit, there is a risk that foreign matter accumulated inside the via hole S1 cannot be sufficiently scraped out. Conversely, if the above pressure contact amount exceeds the above upper limit, the tip of the hair 12a may not sufficiently enter the bottom surface of the via hole S1, and there is a risk that foreign matter accumulated inside the via hole S1 cannot be sufficiently removed.

[0036] Here, regarding the reason why the removal effect of foreign matter accumulated inside the via hole S1 is dramatically enhanced when the ratio of the diameter of the hair 12a to the diameter of the via hole S1 and the amount of pressure contact of the cleaning brush 10 at the setting portion with the bottom of the via hole S1 of the object S are controlled to appropriate values, the inventors consider as follows. As shown in FIG. 3, in order to remove foreign matter accumulated inside the via hole S1, at least the hair 12a needs to be in pressure contact with the bottom of the via hole S1, and the amount of pressure contact of the cleaning brush 10 at the setting portion with the bottom of the via hole S1 of the object S is 0.2 mm or more.

[0037] When the cleaning brush 10 is rotated with the above-mentioned crimping amount being 0.2 mm or more, since one surface of the object S is on the cleaning brush 10 side rather than at the bottom of the via hole S1, the hair 12a first contacts one surface of the object S, and its tip is bent toward the downstream side in the rotation direction of the cleaning brush 10 (the upstream side in the conveying direction D). When passing through the upper part of the via hole S1 in this state, the tip of the hair 12a bent by contacting one surface of the object S extends into the via hole S1 and needs to be in pressure contact with the bottom of the via hole S1. For this purpose, the diameter of the hair 12a needs to be smaller than the diameter of the via hole S1. However, when the diameters of the hair 12a and the via hole S1 are small but close to each other, there will be no space to extend the tip of the bent hair 12a in the via hole S1. On the other hand, the inventors believe that by setting the ratio of the diameter of the hair 12a to the diameter of the via hole S1 to 1 / 3 or less, a space sufficient to extend the tip of the bent hair 12a in the via hole S1 can be secured.

[0038] Furthermore, when the above-mentioned crimping amount is large, as can be seen from FIG. 3, the length of the portion where the hair 12a contacts one surface of the object S becomes large. In this case, even when the hair 12a passes over the via hole S1, the tip will cross over the via hole S1 without entering the bottom of the via hole S1. Therefore, it is necessary to set the above-mentioned crimping amount to 0.7 mm or less to avoid this phenomenon.

[0039] As described above, only when the ratio of the diameter of the hair 12a to the diameter of the via hole S1 is 1 / 3 or less and the crimping amount of the cleaning brush 10 at the contact point with the bottom of the via hole S1 of the object S is 0.2 mm or more and 0.7 mm or less, the foreign matter accumulated inside the via hole S1 can be removed, and under other conditions, almost no foreign matter accumulated inside the via hole S1 can be scraped out.

[0040] The lower limit of the density of the hair 12a of the cleaning brush 10 is preferably 200 kF / inch 2 and more preferably 300 kF / inch. 2 On the other hand, the upper limit of the density of the hair 12a of the cleaning brush 10 is preferably 500 kF / inch 2 and more preferably 400 kF / inch. 2is more preferable. If the density of the bristles 12a is less than the above lower limit, the number of bristles 12a in contact with the bottom of the via hole S1 decreases, and there is a risk that foreign matter accumulated inside the via hole S1 cannot be sufficiently removed. Conversely, if the density of the bristles 12a exceeds the above upper limit, adjacent bristles 12a may overlap, making it difficult for the brush to function.

[0041] The cleaning brush 10 may be in contact with the surface of the object S in a charged state. By bringing the cleaning brush 10 into contact with the surface of the object S in a charged state in this way, foreign matter adhering to the surface of the object S is adsorbed onto the surface of the cleaning brush 10 by the force of static electricity, so that the foreign matter can be removed more effectively.

[0042] As the lower limit of the voltage applied to the cleaning brush 10, for example, -800 V is preferable, and -600 V is more preferable. On the other hand, the above applied voltage is preferably less than, for example, -200 V, and more preferably -300 V or less. By setting the voltage applied to the cleaning brush 10 within the above range, positively charged foreign matter can be efficiently removed in particular. The reference potential (0 V potential) of the applied voltage is the rotation axis of the first counter electrode roller 16 or the part (stage) where the transport mechanism 30 contacts the object S, which will be described later. The same applies to the reference potential of the applied voltage described later.

[0043] As the lower limit of the ratio of the peripheral speed of the cleaning brush 10 to the transport speed of the object S at the contact portion with the surface of the object S, 0.1 times is preferable, and 0.2 times is more preferable. On the other hand, as the upper limit of the above ratio, 0.5 times is preferable, and 0.4 times is more preferable. If the above ratio is less than the above lower limit, there is a risk that foreign matter staying in the via hole S1 cannot be sufficiently removed from the via hole S1. Conversely, if the above ratio exceeds the above upper limit, foreign matter is likely to scatter, and for example, there is a risk that the foreign matter will fall again into other via holes S1 on the upstream side in the transport direction D. That is, by setting the above ratio within the above range in this way, the foreign matter can be efficiently scraped out from the via hole S1 while suppressing the scattering of the foreign matter.

[0044] <Cleaning roller> The cleaning roller 20 is located on the downstream side of the cleaning brush 10. The cleaning roller 20 is arranged with its rotation axis parallel to that of the cleaning brush 10 and contacts the surface of the object S while rotating.

[0045] The rotation direction of the cleaning roller 20 at the contact portion with the surface of the object S is in the forward direction with respect to the conveyance direction D. The cleaning roller 20 may be rotationally driven in the forward direction by a driving device, but it can also be configured to rotate along with the conveyance of the object S. In the configuration of rotating along, the driving device is not necessary. The cleaning roller 20 rotates in the forward direction by contacting the object S whose surface is being conveyed.

[0046] As described above, the cleaning brush 10 scrapes out foreign matter in the via hole S1 to the outside of the via hole S1. Some of the scraped foreign matter is adsorbed and collected by the cleaning brush 10, but there is also foreign matter that is scraped out onto the surface of the object S outside the via hole S1. Since the cleaning roller 20 mainly collects foreign matter on the surface of the object S outside the via hole S1, by arranging the cleaning roller 20 on the downstream side of the cleaning brush 10 in this way, the foreign matter scraped out to the outside of the via hole S1 by the cleaning brush 10 can be collected more reliably.

[0047] The cleaning roller 20 can be configured to have, for example, a columnar core metal 21, a cylindrical inner layer portion 22 covering the circumferential surface of this core metal 21, and a thin film cylindrical outer layer portion 23 covering the outer circumferential surface of this inner layer portion 22.

[0048] As the material of the inner layer portion 22, an elastic member having conductivity is used. Examples of such an elastic member include polyester-based urethane containing carbon.

[0049] As the material of the outer layer portion 23, a material that can be charged with a charge that adsorbs foreign matter adhering to the surface of the object S by the force of an electric field is preferable. Examples thereof include polyurethanes such as acrylic mixed polyurethane and fluorine mixed polyurethane. By forming the outer layer portion 23 with polyurethane, the abrasion resistance is excellent as compared with the case of forming it with a silicone resin, butyl rubber, or the like, and contamination by a plasticizer or a low molecular weight substance can be reduced.

[0050] The above-mentioned acrylic mixed polyurethane means a polyester polyurethane or a polyether polyurethane as a main component, and further (1) a thermoplastic polyurethane and a silicone-acrylic copolymer resin, (2) an acrylic resin (for example, a graft compound in which an aminoethyl group is grafted to a main chain composed of a methacrylic acid-methyl methacrylate copolymer) and a thermoplastic polyurethane, or (3) a mixture containing an acrylic resin, a polyurethane, and a fluorine-based surface coating agent. By using acrylic mixed polyurethane as the material of the outer layer portion 23, foreign matter that is easily negatively charged is easily removed from the surface of the object S. Note that the "main component" is the component with the highest content, for example, a component contained in an amount of 50% by mass or more.

[0051] The above-mentioned fluorine mixed polyurethane means a material having polyurethane as a main component and a mixture containing a thermoplastic polyurethane and a urethane-fluorine copolymer. By using fluorine mixed polyurethane as the material of the outer layer portion 23, foreign matter that is easily positively charged is easily removed from the object S.

[0052] As the lower limit of the average thickness of the outer layer portion 23, 2 μm is preferable, and 5 μm is more preferable. On the other hand, as the upper limit of the average thickness of the outer layer portion 23, 500 μm is preferable, and 50 μm is more preferable. If the average thickness of the outer layer portion 23 is less than the above lower limit, the surface of the cleaning roller 20 cannot be sufficiently charged, and there is a possibility that the adsorption effect of foreign matter cannot be sufficiently obtained. Conversely, if the average thickness of the outer layer portion 23 exceeds the above upper limit, there is a possibility that good charging characteristics for adsorbing foreign matter cannot be obtained.

[0053] The cleaning roller 20 may be in contact with the surface of the object S in a charged state. By bringing the cleaning roller 20 into contact with the surface of the object S in a charged state in this way, foreign matter adhering to the surface of the object S is adsorbed onto the surface of the cleaning roller 20 by the force of static electricity, so that the foreign matter can be removed more effectively.

[0054] As the lower limit of the voltage applied to the cleaning roller 20, for example, -400 V is preferable, and -200 V is more preferable. On the other hand, the applied voltage is, for example, less than 0 V, and preferably -50 V or less. By setting the voltage applied to the cleaning roller 20 within the above range, positively charged foreign matter can be removed efficiently. Note that the voltages applied to the cleaning brush 10 and the cleaning roller 20 are preferably of the same polarity.

[0055] <Conveying mechanism> The conveying mechanism 30 applies a propulsive force for conveying to the object S. The conveying mechanism 30 includes an upstream conveying mechanism 30a disposed upstream of the cleaning brush 10 in the conveying direction D and a downstream conveying mechanism 30b disposed downstream of the cleaning roller 20 in the conveying direction D.

[0056] (Upstream conveying mechanism) The upstream conveying mechanism 30a conveys the object S and inserts it into the cleaning brush 10. As shown in FIG. 1, it has a plurality of belt conveying units 31. Each belt conveying unit 31 has an endless belt 33 wound between a pair of conveying rollers 32 spaced apart along the conveying direction D.

[0057] Of the pair of conveying rollers 32, one is a driving roller to which a rotational force is applied, and the other is a driven roller that rotates with the endless belt 33 due to the rotation of the driving roller. The plurality of belt conveying units 31 are arranged at regular intervals in the horizontal direction perpendicular to the conveying direction D.

[0058] (Downstream conveying mechanism) The downstream conveying mechanism 30b conveys the object S that has passed through the cleaning roller 20 out. Since the downstream conveying mechanism 30b can be configured in the same way as the upstream conveying mechanism 30a, detailed description thereof will be omitted.

[0059] <Other configurations> (Guide roller) It is disposed upstream of the cleaning brush 10 in the conveying direction D and assists in conveying the object S while contacting the surface of the object S. A guide roller may be provided.

[0060] The guide roller is rotatably disposed parallel to the cleaning brush 10 with respect to the rotation axis. This guide roller rotates along with the conveyance of the object S. That is, the rotation direction of the guide roller at the contact point with the surface of the object S is the forward direction with respect to the conveyance direction D. Note that the guide roller may be configured to be rotationally driven. For example, by rotationally driving the guide roller so as to be in the forward direction with respect to the conveyance direction D of the object S, the conveyance speed of the object S in the cleaning device 1 can be made constant.

[0061] It is preferable that another roller that contacts the surface on the opposite side of the object S across the object S at the position where the guide roller contacts the surface of the object S is provided. For example, as this other roller, one conveying roller 32 of the upstream conveying mechanism 30a can be used. Hereinafter, the case where the other roller is one conveying roller 32 of the upstream conveying mechanism 30a will be taken as an example and the description will be continued, but the other roller is not limited to the conveying roller 32, and for example, a dedicated conveying roller may be provided as the other roller.

[0062] The guide roller is arranged so as to have a gap between it and the conveying roller 32 such that both sides of the object S contact the circumferential surfaces of these two rollers. By inserting the object S between the guide roller and the conveying roller 32, the traveling direction of the object S can be controlled. For example, when the object S is in the form of a thin film, the tip is likely to bend. Even in such a case, the bending of the tip is suppressed by inserting it between the guide roller and the conveying roller 32, and the tip of the object S can enter easily and surely between the cleaning brush 10 and the first opposing electrode roller 16 described later.

[0063] The material of the guide roller is preferably one with a small frictional force between it and the object S, and metals, resins, etc. can be used as the material for forming the guide roller.

[0064] Preferably, no other roller that contacts the surface of the object S is arranged between the guide roller and the cleaning brush 10.

[0065] (First foreign matter recovery mechanism) As a first foreign matter recovery mechanism for recovering foreign matter adhering to the cleaning brush 10, the cleaning device 1 may have, for example, as shown in FIG. 2, a first dust collecting roller 13, a first scraper 14, and a first foreign matter recovery section 15.

[0066] The first dust collecting roller 13 is arranged parallel to the cleaning brush 10 with respect to the rotation axis and contacts the surface of the cleaning brush 10 in a charged state. The rotation direction of the first dust collecting roller 13 at the contact point with the surface of the cleaning brush 10 is preferably opposite to the rotation direction of the cleaning brush 10. By setting the rotation direction of the first dust collecting roller 13 to be opposite to the rotation direction of the cleaning brush 10 in this way, foreign matter adhering to the cleaning brush 10 can be efficiently recovered.

[0067] The first dust collecting roller 13 can be made of a conductive material. Examples of the conductive material include metal materials such as stainless steel, copper, and aluminum. When a conductive material that is prone to oxidation, such as copper or aluminum, is used for the first dust collecting roller 13, it is preferable to perform a corrosion-resistant plating treatment such as nickel plating or gold plating on the surface of the first dust collecting roller 13.

[0068] Also, the potential of the first dust collecting roller 13 is preferably of the same polarity as the potential of the cleaning brush 10 and has a larger absolute value. By configuring it in this way, foreign matter attached to the cleaning brush 10 can be efficiently collected. Note that even when the cleaning brush 10 is used in a non-charged state, it is preferable that the potential of the first dust collecting roller 13 is fixed. By fixing the potential of the first dust collecting roller 13, the cleaning brush 10 can be charged without applying a voltage to the cleaning brush 10 itself, and adsorption of foreign matter by the force of static electricity can be generated.

[0069] The first scraper 14 is, for example, a rectangular plate, and one side forming the rectangle contacts the surface of the first dust collecting roller 13 over the rotation axis direction of the first dust collecting roller 13 (hereinafter, the portion in contact with the first dust collecting roller 13 is also referred to as the "tip portion"). The first scraper 14 is arranged such that its tip portion faces downward, and at the contact position with the surface of the first dust collecting roller 13, it is disposed at a position where the rotation direction of the first dust collecting roller 13 is from bottom to top.

[0070] The first scraper 14 is formed of an elastic body made of a synthetic resin such as thermosetting polyurethane. As the first dust collecting roller 13 rotates, foreign matter attached to the surface of the first dust collecting roller 13 is scraped off by the tip portion of the first scraper 14. As a result, the surface of the first dust collecting roller 13 becomes a clean state from which foreign matter has been removed.

[0071] The first foreign matter collection part 15 is in a tray shape and is disposed below the tip portion of the first scraper 14. The foreign matter scraped off by the first scraper 14 falls and is collected into the first foreign matter collection part 15.

[0072] (Second foreign object recovery mechanism) As the second foreign object recovery mechanism for recovering foreign objects attached to the cleaning roller 20, the cleaning device 1 may have, for example, as shown in FIG. 2, a brush roller 24, a second dust collecting roller 25, a second scraper 26, and a second foreign object recovery unit 27.

[0073] The brush roller 24 is arranged with its rotation axis parallel to that of the cleaning roller 20 and contacts the surface of the cleaning roller 20 in a charged state. It is preferable that the rotation direction of the brush roller 24 at the contact portion with the surface of the cleaning roller 20 is opposite to the rotation direction of the cleaning roller 20. By setting the rotation direction of the brush roller 24 to be opposite to the rotation direction of the cleaning roller 20 in this way, foreign objects attached to the cleaning roller 20 can be efficiently recovered. Note that the brush roller 24 can have, for example, the same configuration as the cleaning brush 10.

[0074] It is preferable that the potential of the brush roller 24 has the same polarity as that of the cleaning roller 20 and a larger absolute value. By setting the potential of the brush roller 24 to have the same polarity as that of the cleaning roller 20 and a larger absolute value in this way, foreign objects attached to the cleaning roller 20 are more likely to move from the cleaning roller 20 to the brush roller 24 at the above contact portion. Therefore, foreign objects attached to the cleaning roller 20 can be recovered more reliably.

[0075] The second dust collecting roller 25 is arranged with its rotation axis parallel to that of the cleaning roller 20 and contacts the surface of the brush roller 24 in a charged state. Since the second dust collecting roller 25 can be configured in the same way as the first dust collecting roller 13, detailed description is omitted.

[0076] The second scraper 26 is, for example, a rectangular plate, and one side forming the rectangle contacts the surface of the second dust collecting roller 25 over the rotation axis direction of the second dust collecting roller 25. Since the second scraper 26 can be configured in the same way as the first scraper 14, detailed description is omitted.

[0077] The second foreign matter collection part 27 is in a tray shape and is disposed below the tip of the second scraper 26. The foreign matter scraped by the second scraper 26 falls and is collected into the second foreign matter collection part 27.

[0078] (Counter electrode roller) The cleaning device 1 may include a first counter electrode roller 16 that contacts a surface opposite to the surface that contacts the cleaning brush 10 of the object S, and a second counter electrode roller 28 that contacts a surface opposite to the surface that contacts the cleaning roller 20 of the object S.

[0079] The first counter electrode roller 16 is rotatably disposed at a position where the rotation axis is parallel and opposite to the cleaning brush 10, and the second counter electrode roller 28 is rotatably disposed at a position where the rotation axis is parallel and opposite to the cleaning roller 20.

[0080] The first counter electrode roller 16 and the second counter electrode roller 28 (collectively also referred to as "counter electrode roller") contact the back surface of the object S in a grounded state. Note that any one or all of the counter electrode rollers may be used while being charged. When each counter electrode roller is charged, a voltage having the same polarity and lower than the voltage applied to the cleaning brush 10 or a voltage with opposite positive and negative polarities is applied to the first counter electrode roller 16, and a voltage having the same polarity and lower than the voltage applied to the cleaning roller 20 or a voltage with opposite positive and negative polarities is applied to the second counter electrode roller 28. Thereby, the adsorption effect due to the electric field force of the cleaning brush 10 and the cleaning roller 20 is promoted, and the foreign matter adhering to the surfaces of the object S on the cleaning brush 10 and cleaning roller 20 sides is more likely to be adsorbed by the cleaning brush 10 and the cleaning roller 20.

[0081] The counter electrode roller rotates along with the conveyance of the object S. That is, the rotation direction of the counter electrode roller at the contact portion with the back surface of the object S is in the forward direction with respect to the conveyance direction D.

[0082] The above-described counter electrode roller is partially or entirely formed of a conductive material. Examples of such a conductive material include metal materials such as stainless steel, copper, and aluminum. The counter electrode roller can be formed only of the above-described conductive material, but as represented by the second counter electrode roller 28 in FIG. 2, it may be configured such that an outer peripheral surface of a core metal 28a formed of the conductive material is covered with an insulating layer 28b such as a synthetic resin.

[0083] (Unitization) As shown in FIG. 1, in the cleaning device 1, the cleaning brush 10 and the first foreign matter recovery mechanism are unitized (brush unit 1a), and the cleaning roller 20 and the second foreign matter recovery mechanism are unitized (roller unit 1b). The brush unit 1a and the roller unit 1b are each independently configured to be detachable. By configuring each unit to be detachable in this way, the convenience of operations such as discarding the recovered or removed foreign matter is improved. Also, when it is necessary to exchange the type of unit depending on the object S or the type of foreign matter, the entire unit can be exchanged.

[0084] <Advantages> In the cleaning device 1, since the diameter of the bristles 12a of the brush portion 12 is set to 1 / 3 or less of the via hole S1, the tips of the bristles 12a can enter the via hole S1. Also, since the amount of pressure contact of the cleaning brush 10 at the contact portion with the bottom of the via hole S1 is set to be 0.2 mm or more and 0.7 mm or less, the tips of the bristles 12a can surely contact the foreign matter and scrape the foreign matter out of the via hole S1.

[0085] [Other Embodiments] The present invention is not limited to the above-described embodiments, and can be implemented in various modified and improved embodiments in addition to the above-described aspects.

[0086] In the above embodiment, the case where the cleaning device removes foreign matter adhering to one surface of the object has been described. However, the cleaning device may remove foreign matter adhering to both surfaces of the object, that is, in addition to the above one surface, foreign matter adhering to the other surface. In this case, another cleaning brush and cleaning roller are provided for removing foreign matter adhering to the other surface.

[0087] In the above embodiment, the case where the cleaning roller is located downstream of the cleaning brush has been described. However, the position of the cleaning roller is not limited to the downstream side of the cleaning brush. Also, a cleaning device not provided with a cleaning roller is also within the scope intended by the present invention. In any cleaning device, the effect of scraping foreign matter out of the via holes can be achieved in the same manner as in the above embodiment.

[0088] In the above embodiment, the case where the rotation direction of the cleaning brush at the contact portion with the object surface is opposite to the conveyance direction and the rotation direction of the cleaning roller at the contact portion with the object surface is in the same direction as the conveyance direction has been described. However, the rotation directions of the above cleaning brush and the above cleaning roller are not limited to the above combination.

[0089] Also, the conveyance mechanism is not limited to the above-described configuration. Any configuration can be adopted as long as it can convey the object.

Example

[0090] Hereinafter, the present invention will be described in more detail with reference to examples, but the invention is not limited to the following examples.

[0091] As the object S, a film made of epoxy resin with a thickness of 1000 μm and a width of 350 mm was prepared. A plurality of via holes S1 having the size shown in FIG. 4 were provided on one surface of this film.

[0092] A foreign object (made of epoxy resin) with a diameter of 10 μm was attached to this object S. The foreign objects were distributed in several numbers at the bottom of each via hole S1. The presence of several foreign objects at the bottom of each via hole S1 was confirmed by observing the bottom of the via hole S1 with a microscope.

[0093] Using the cleaning device 1 shown in FIGS. 1 and 2, the foreign objects on one surface of the object S were removed with different brush rollers 10 of types a to c shown in Table 1 at the pressing amounts shown in Table 2. The conveyance speed of the conveyed object S was 5 m / min, the potentials of the first counter electrode roller 16 and the second counter electrode roller 28 were 0 V, the potential of the cleaning brush 10 was 0 V, the potential of the cleaning roller 20 was -100 V, the potential of the brush roller 24 was -400 V, and the potential of the second dust collecting roller 25 was -800 V. The potential of the first dust collecting roller 13 was changed between -800 V and -2000 V.

[0094]

Table 1

[0095] The removability of foreign objects at the bottom of the via hole S1 of the object S after foreign object removal was confirmed again with a microscope and classified into the following three categories. The results are shown in Table 2. Although the first dust collecting roller 13 showed better results when the absolute value of the applied voltage was larger, it did not affect the following determination so much. A: No foreign objects are present. B: Although the foreign objects have decreased, residues of foreign objects are recognized around the periphery of the bottom of the via hole S1. C: Almost no foreign objects have been removed.

[0096]

Table 2

[0097] From the results in Table 2, in the case of Nos. 5, 6, 8, and 9 using the cleaning device 1 where the ratio of the diameter of the hair 12a to the diameter of the via hole S1 is about 3 / 10 (1 / 3 or less), and the amount of pressure contact of the cleaning brush 10 at the contact portion with the bottom of the via hole S1 of the object S is 0.2 mm or more and 0.7 mm or less, it is possible to remove foreign matter at the bottom of the via hole S1. On the other hand, in Nos. 1 to 3, since the above ratio of diameters is 1 / 2 (exceeding 1 / 3), and in Nos. 4 and 7, since the above amount of pressure contact is 0.8 mm (exceeding 0.7 mm), it can be seen that no foreign matter can be removed at all.

Industrial Applicability

[0098] As described above, the cleaning device of the present invention can effectively remove foreign matter even from an object having via holes on its surface.

Explanation of Reference Numerals

[0099] 1 Cleaning device 1a Brush unit 1b Roller unit 10 Cleaning brush 11 Shaft 12 Brush part 12a Hair 13 First dust collecting roller 14 First scraper 15 First foreign matter collection part 16 First counter electrode roller 20 Cleaning roller 21 Shaft 22 Inner layer part 23 Outer layer part 24 Brush roller 25 Second dust collecting roller 26 Second scraper 27 Second foreign matter collection part 28 Second counter electrode roller 28a Shaft 28b Insulating layer 30 Conveying mechanism 30a Upstream conveying mechanism 30b Downstream conveying mechanism 31 Belt conveyor section 32 Conveyor roller 33 Endless belt S Object S1 Via hole D Conveying direction

Claims

1. A cleaning device for removing foreign matter adhering to at least one surface of a plate-shaped or film-shaped object having a bottomed via hole, which is rotatably disposed about a rotation axis perpendicular to the conveyance direction of the object and parallel to the object surface, and includes a roller-shaped cleaning brush that contacts the object surface, wherein the cleaning brush has a cylindrical mandrel and a brush portion formed by implanting a plurality of hairs on the peripheral surface of the mandrel, the ratio of the diameter of the hair to the diameter of the via hole is 1 / 3 or less, and the amount of pressure contact of the cleaning brush at the contact portion with the bottom of the via hole of the object is 0.2 mm or more and 0.7 mm or less.

2. A cleaning device according to claim 1, further comprising a cleaning roller that is located on the downstream side of the cleaning brush, has a rotation axis disposed in parallel with the cleaning brush, and contacts the object surface while rotating, wherein the rotation direction of the cleaning brush at the contact portion with the object surface is opposite to the conveyance direction, and the rotation direction of the cleaning roller at the contact portion with the object surface is the same as the conveyance direction.

3. The cleaning device according to claim 1 or 2, wherein the cleaning brush contacts the one surface while being charged.

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