Polishing tape

Abstract

To provide a polishing tape which can suppress scattering of shavings after polishing.SOLUTION: A polishing tape comprises a tape-like base material and a binder resin layer containing inorganic particles, and has a plurality of suction holes that penetrate the tape-like base material and the binder resin layer.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The following disclosure relates to a polishing tape.

Background Art

[0002] Conventionally, for a glass substrate used in the manufacture of a liquid crystal panel, a process for removing foreign matter present on the surface has been performed. For example, in Patent Document 1, a foreign matter removing apparatus for a substrate and a foreign matter removing method for a substrate are disclosed for favorably removing organic foreign matter adhering to the substrate surface in the manufacturing process without leaving debris and without damaging the substrate surface.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, after the film forming process and the curing process of polyimide (PI), which is a material of the alignment film, convex portions may occur on the substrate surface due to foreign matters such as heating products and heating sublimates of polyimide, and biting-in of bubbles. In order to remove the convex portions, a process (PI polishing process) of shaving and flattening the convex portions using a polishing tape may be performed. In this process, when the substrate surface is polished with the polishing tape, the shaved chips after polishing may scatter, new defects due to foreign matters may occur, and the number of defects may increase compared to before the polishing process.

[0005] The present invention has been made in view of the above situation, and an object thereof is to provide a polishing tape capable of suppressing scattering of shaved chips after polishing.

Means for Solving the Problems

[0006] (1) One embodiment of the present invention is a polishing tape comprising a tape-shaped base material and a binder resin layer containing inorganic particles, and having a plurality of suction holes penetrating through the tape-shaped base material and the binder resin layer.

[0007] (2) Further, in a certain embodiment of the present invention, in addition to the configuration of (1) above, the tape-shaped base material is a polyethylene terephthalate film, and it is a polishing tape.

[0008] (3) Further, in a certain embodiment of the present invention, in addition to the configuration of (1) or (2) above, the inorganic particles are alumina particles, and it is a polishing tape.

Advantages of the Invention

[0009] According to the present invention, it is possible to provide a polishing tape capable of suppressing the scattering of chips after polishing.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Embodiments for Carrying Out the Invention

[0011] Hereinafter, embodiments of the present invention will be described. The present invention is not limited to the content described in the following embodiments, and design changes can be appropriately made within the scope that satisfies the configuration of the present invention. In the following description, the same reference numerals are commonly used for the same parts or parts having the same functions among different drawings as appropriate, and the repeated description thereof will be omitted as appropriate. Each aspect of the present invention may be appropriately combined within the scope not departing from the gist of the present invention.

[0012] (Embodiment 1) FIG. 1 is a schematic cross-sectional view showing an example of a polishing tape. The polishing tape 100 in FIG. 1 includes a tape-shaped base material 10 and a binder resin layer 20 containing inorganic particles 21, but does not have suction holes. FIG. 2 is a schematic cross-sectional view showing an example of a polishing process using the polishing tape of FIG. 1. The arrow A in the figure indicates the feeding direction (transport direction) of the polishing tape 100, and the arrow C indicates the transport direction of the glass substrate 300. As shown in FIG. 2, when the surface of the glass substrate 300 is polished by the polishing head 200 through the polishing tape 100 of FIG. 1, when the defective foreign matter 310 present on the substrate surface is polished, the chips (polishing foreign matter) 320 generated by the polishing will scatter. The chips 320 attached to the surface of the glass substrate 300 after the polishing process will become new defects. Although cleaning may be performed after the polishing process and before the subsequent process, the chips 320 may stick to the surface of the glass substrate 300 and cannot be removed.

[0013] FIG. 3 is a schematic cross-sectional view showing an example of the polishing tape of the present invention. The polishing tape 110 in FIG. 3 includes a tape-shaped substrate 10 and a binder resin layer 20 containing inorganic particles 21, and has a plurality of suction holes 30 penetrating through the tape-shaped substrate 10 and the binder resin layer 20. FIG. 4 is a schematic cross-sectional view showing an example of a polishing process using the polishing tape of FIG. 3. The arrow A in the figure indicates the feeding direction (transport direction) of the polishing tape 110, and the arrow C indicates the transport direction of the glass substrate 300. In the polishing apparatus shown in FIG. 4, the polishing head 200 has a hollow structure for vacuum suction. Specifically, a cavity 210 is provided inside the main body of the polishing head 200, and a net-like portion with a plurality of minute suction holes 220 formed at the tip of the polishing head 200 is provided.

[0014] In the present embodiment, the shape of the suction holes 30 provided in the polishing tape 110 is not particularly limited, and examples thereof include a circular shape and a polygonal shape. The size (average value of the length of the longest part of the hole (diameter in the case of a circular shape, diagonal length in the case of a polygonal shape)) of the suction holes 30 in a plan view is preferably 0.1 μm or more and 5.0 μm or less, and more preferably 0.5 μm or more and 1.0 μm or less. The pitch (arrangement interval) of the suction holes 30 in the polishing tape 110 is, for example, 2.5 μm or more and 20.0 μm or less, preferably 5.0 μm or more and 10.0 μm or less, and the area ratio of the suction holes 30 in the polishing tape 110 is preferably 0.1% or more and 6% or less, and more preferably 0.2% or more and 3.1% or less. Further, the shape of the suction holes 220 provided in the polishing head 200 is not particularly limited, and examples thereof include a circular shape and a polygonal shape. The size (average value of the length of the longest part of the hole) of the suction holes 220 in a plan view is preferably 0.1 μm or more and 5.0 μm or less, and more preferably 0.5 μm or more and 1.0 μm or less.

[0015] According to the polishing tape 110 of FIG. 3, since the suction holes 30, which are minute through-holes, are provided, by performing vacuum suction from the polishing head 200 side of the polishing processing apparatus, the chips 320 are suctioned to the polishing tape 110 side. Among the chips 320, those larger than the suction holes 30 stick to the surface of the polishing tape 110 by the suction force, and those smaller than the suction holes 30 are caught inside the suction holes 30. That is, the polishing tape 110 can capture the chips 320 and prevent the chips 320 from scattering. Therefore, it is possible to prevent foreign matter from reattaching to the glass substrate 300 after the polishing process for removing foreign matter. In addition, if the binder resin layer 20 of the polishing tape 110 has adhesiveness, scattering of the chips 320 can be more effectively prevented.

[0016] As the polishing tape 110, for example, a tape-shaped base material 10 made of polyethylene terephthalate (PET) with a binder resin layer 20 in which inorganic particles 21 made of alumina are dispersed laminated on one surface can be used. The polishing tape 110 is usually thin and elongated in a strip shape, but it may be continuously used for a plurality of polishing processes while being conveyed by the polishing processing apparatus, or it may be used one by one for each polishing process.

[0017] The material of the tape-shaped base material 10 is not particularly limited, but it is preferably tough enough not to be damaged by friction with the polishing head 200 during the polishing process. Also, it is preferably durable and flexible suitable for conveyance by the polishing processing apparatus. Specifically, for example, polyesters such as polyethylene terephthalate (PET), polyethylene, etc. can be mentioned.

[0018] The thickness of the tape-shaped base material 10 is not particularly limited, but it is preferably 10 μm or more and 60 μm or less, and more preferably 20 μm or more and 30 μm or less.

[0019] The width of the tape-shaped base material 10 is not particularly limited, but it is preferably 4 mm or more and 35 mm or less, and more preferably 8 mm or more and 18 mm or less.

[0020] The material of the binder resin layer 20 is not particularly limited, but it preferably has toughness such that it will not be damaged by friction with the polishing head 200 during the polishing process.

[0021] The thickness of the binder resin layer 20 is not particularly limited, but it is preferably 1 μm or more and 8 μm or less, and more preferably 2 μm or more and 4 μm or less.

[0022] The material of the inorganic particles 21 is not particularly limited, but it preferably has toughness such that it will not be damaged by friction with the polishing head 200 during the polishing process. Specifically, for example, alumina (aluminum oxide) and the like can be mentioned.

[0023] The average particle diameter of the inorganic particles 21 is not particularly limited. The surface roughness Ra of the inorganic particles 21 is, for example, 0.02 μm or more and 0.08 μm or less.

[0024] (Embodiment 2) FIG. 5 is a cross-sectional schematic view showing another example of the polishing process using the polishing tape of FIG. 3. In the present embodiment, compared with Embodiment 1, the size of the suction holes 30 provided in the polishing tape 110 and the suction holes 220 provided in the polishing head 200 are formed larger. Thereby, when vacuum suction is performed from the polishing head 200 side of the polishing processing apparatus, the cut chips 320 can pass through the suction holes 30 of the polishing tape 110 and the suction holes 220 of the polishing head 200 and be collected into the polishing head 200. Also in this case, similar to Embodiment 1, it is possible to prevent the cut chips 320 from scattering. Therefore, it is possible to prevent foreign matter from reattaching to the glass substrate 300 after the polishing process for removing foreign matter.

[0025] In the above-described embodiment, the case of removing foreign matter on the surface of the glass substrate has been exemplified, but the polishing tape of the present invention may be used for polishing other than the glass substrate. Also, the type of foreign matter to be removed is not particularly limited, and according to the present invention, it is possible to remove both organic matter and inorganic matter.

Explanation of Reference Numerals

[0026] 10: Base material 20: Binder resin layer 21: Inorganic particles 30: Suction hole 100, 110: Polishing tape 200: Polishing head 210: Cavity 220: Suction hole 300: Glass substrate 310: Defect foreign matter 320: Scrapings (polishing foreign matter) A: Feeding direction of the polishing tape C: Conveying direction of the glass substrate

Claims

1. A tape-shaped substrate, A binder resin layer containing inorganic particles, and having, A plurality of suction holes penetrating through the tape-shaped substrate and the binder resin layer A polishing tape.

2. The polishing tape according to claim 1, wherein the tape-shaped substrate is a polyethylene terephthalate film.

3. The polishing tape according to claim 1, wherein the inorganic particles are alumina particles.

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