JP2008290189A - Polishing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polishing machine capable of polishing and removing only abnormal projections without damaging a film in a normal thickness with a polishing sheet in contact with the surface of a glass substrate. <P>SOLUTION: In this polishing machine, the film 200 on the surface of the glass substrate W is polished by the polishing sheet 23 by pressing a polishing plate 20 with the polishing sheet 23 stuck on the polishing surface plate face 20a, onto the surface of the glass substrate W formed with the film 200 and in-plane moving the polishing plate 20 in relation to the glass substrate W. The polishing sheet 23 includes: a polishing layer 26 composed of abrasive grains 27 and binder resin; and resin coating layers 24 integrally formed at least on the surface on the side of the polishing layer 26 in contact with the glass substrate W. The abrasive grains are projected from the side of the polishing layer 26. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a polishing machine for polishing a colored film formed on a glass substrate such as a color filter for a liquid crystal display device.

For example, Patent Document 1 has been proposed as a polishing machine for the colored layer of the color filter described above.
In this polishing machine, a rectangular polishing plate whose long side is longer than the short side of the glass substrate is placed on the surface of the stationary square glass substrate (color filter) on which the colored layer is formed. Placed parallel to the side, while pressing the glass substrate surface with the polishing plate, the polishing plate is rotated eccentrically around the vertical direction of the glass substrate to swing the polishing plate in the short side direction of the glass substrate and polish The color filter surface is polished by moving the plate in the long side direction of the glass substrate.
According to this polishing machine, an advantage that the entire surface of the glass substrate can be uniformly polished is obtained as compared with a conventional Oscar type polishing machine.

  By the way, the color filter CF for a liquid crystal panel has a structure in which a black matrix BM is formed on the surface of a flat glass substrate W and a colored film (RGB film) is formed thereon as shown in FIG. If foreign matters are mixed in the colored film in the process, abnormal projections 300 may be generated on the RGB film. As shown in FIG. 8, the height S2 of the abnormal protrusion 300 is generally about 10 to 40 μm while the RGB film thickness S1 including the normal protrusion is generally 1.5 to 2.0 μm. If such an abnormal protrusion 300 is generated, the panel is stuck in the manufacturing process, which causes a display defect.

  However, conventional polishing machines are not suitable for removing such abnormal protrusions. This is because a conventional polishing machine is for entire surface polishing, and even if only abnormal protrusions are to be polished, there is a risk that even a normal film thickness portion may be removed.

Therefore, in the previously filed Japanese Patent Application No. 2007-84946, the present applicant, when the polishing plate is pressed against the glass substrate against the polishing platen surface of the polishing plate, the surface of the glass substrate precedes the polishing sheet. There has been proposed a polishing machine that optimally holds the clear run between the surface of the glass substrate and the polishing sheet by providing a clearance adjustment pad made of an elastic body that abuts and deforms in response to the pressing force.
By providing this clearance adjustment pad, the polishing sheet can be brought into contact with only abnormal projections existing on the film on the surface of the glass substrate during polishing, and can be brought into non-contact with a film having a normal thickness. It is possible to polish and remove only abnormal protrusions without reducing the normal film thickness.
For polishing such abnormal protrusions, a fixed abrasive polishing sheet having excellent grinding force embedded with diamond abrasive grains or alumina abrasive grains is used.

However, the following problems remain in the polishing with the clearance adjustment pad.
That is, since the clearance adjustment pad is made of an elastic body, the amount of deformation is not constant for each polishing, and thus it is difficult to always keep the clearance between the surface of the polishing sheet and the abnormal protrusion constant, and Further, since the thickness of the clearance adjusting pad varies from lot to lot, it is necessary to set polishing conditions (for example, to secure an optimum clearance by adjusting the polishing pressure) every time the pad is replaced, and this is a problem that polishing reproducibility is low.
In particular, diamond abrasive grains have a high abrasive hardness and a large particle diameter. Therefore, if the clearance between the surface of the glass substrate and the polishing sheet becomes too small, the normal thickness of the glass substrate surface is reduced. Abrasive grains protruding from the surface of the polishing sheet come into contact with each other to cause polishing scratches.
JP 2004-195602 A

  The present invention has been made in view of the above circumstances, and is a polishing machine capable of polishing and removing only abnormal protrusions without damaging a film having a normal thickness in a state where a polishing sheet is in contact with the surface of a glass substrate. The purpose is to provide.

  That is, the polishing machine according to claim 1 is configured such that the polishing plate is pressed against the glass substrate while pressing the polishing plate with the polishing sheet attached to the surface of the polishing platen on the surface of the glass substrate on which the film is formed. In the polishing machine that polishes the film on the surface of the glass substrate with the polishing sheet by moving in-plane, the polishing sheet comprises a polishing layer composed of abrasive grains and a binder resin, and at least the glass substrate of the polishing layer And a resin coating layer integrally formed on the surface in contact with the surface, and the abrasive grains protrude from the side surface of the polishing layer.

  According to a second aspect of the present invention, in the polishing machine according to the first aspect, the resin coating layer is made of the binder resin.

  The invention according to claim 3 is the polishing machine according to claim 1 or 2, wherein the thickness of the resin coating layer is 3 to 5 μm.

  According to a fourth aspect of the present invention, there is provided the polishing machine according to any one of the first to third aspects, wherein the glass is disposed below the conveyance path for conveying the glass substrate along the surface direction. A lower surface plate on which the substrate is placed is disposed, and a polishing head for polishing the upper surface of the glass substrate that has been conveyed is provided above the lower surface plate, and the polishing sheet is placed below the main body of the polishing head. The polishing plate as an upper surface plate is provided so as to be movable in the vertical direction, and the polishing plate is pressed against the glass substrate between the main body of the polishing head and the polishing plate, and the pressing force is adjusted. And a drive mechanism for orbitally moving the polishing head so as to include at least a movement component in an in-plane direction orthogonal to the conveyance direction of the glass substrate. It is a symptom.

  According to a fifth aspect of the present invention, in the polishing machine according to any one of the first to fourth aspects, the glass substrate is a color filter of a display panel, and the film is an RGB colored film. It is characterized by being.

According to the invention of claim 1, since the resin coating layer made of the binder resin is formed on the surface of the polishing sheet that contacts the glass substrate of the polishing sheet, and the abrasive grains are projected only from the side surface of the polishing sheet. On the contact surface with the glass substrate, the abrasive grains of the polishing layer are covered with the resin coating layer and do not protrude to the glass substrate side, so even if the polishing sheet is in contact with the glass substrate during polishing, the film Polishing scratches due to the contact of abrasive grains cannot occur on the surface, and abnormal protrusions on the film surface are ground from the side by abrasive grains protruding from the side surface of the polishing layer. Therefore, it is possible to efficiently and surely remove only the abnormal protrusion without damaging the film surface of the glass substrate.
In addition, since the surface of the resin coating layer in contact with the glass substrate does not participate in the grinding of abnormal protrusions, the polishing pressure during polishing can be reduced. Abrasion can be suppressed, and the life of the polishing sheet can be extended.

  According to the invention of claim 2, since the binder resin constituting the polishing layer is used as the material of the resin coating layer, the adhesion between the resin coating layer and the polishing layer is improved and both are firmly fixed. Can do.

  According to the invention of claim 3, since the thickness of the resin coating layer is 3 to 5 μm, a gap of at least 3 μm or more is provided between the film surface of the glass substrate and the abrasive grains protruding from the side portion of the polishing layer. As a result, the protruding abrasive grains can be prevented from coming into contact with the film surface of the glass substrate during polishing, and abnormal protrusions can be reliably ground and removed by the protruding abrasive grains.

  According to the fourth aspect of the invention, the polishing plate is provided on the polishing head so as to be movable in the vertical direction, and the polishing plate is pressed against the glass substrate by the press adjusting mechanism. The pressing force can be adjusted to a suitable pressing force that can efficiently polish the abnormal protrusion.

  Furthermore, according to the fifth aspect of the present invention, it is possible to efficiently and surely remove abnormal protrusions generated on the colored film of the color filter without damaging the surface of the color filter.

Hereinafter, an embodiment of a polishing machine of the present invention will be described with reference to FIGS.
The polishing machine of this embodiment is for polishing a colored film (RGB film) of a color filter for a liquid crystal display device, and FIG. 1 is a main part of a production line of a glass substrate equipped with the polishing machine of this embodiment. FIG. 2 is a side view showing the main part configuration, FIG. 3 is a cross-sectional view showing the lower configuration of the polishing plate, as viewed from the side in the conveyance direction of the glass substrate, and FIG. 4 is polished on the glass substrate. FIG. 5 shows the structure of the polishing sheet, (a) is a plan view, (b) is a side view, and FIG. 6 is a view of the polishing plate as seen from below. FIG. 7 is a cross-sectional view showing the structure of the polishing head as seen from the side of the glass substrate in the conveying direction, where (a) is a diagram showing a state before the polishing plate is pressed against the glass substrate, and (b) is the polishing plate. It is a figure which shows the state which pressed the glass substrate.

  1 and 2, reference numeral 1 denotes a conveyance conveyor (conveyance path) that conveys a glass substrate W (in this embodiment, a color filter) in the direction of arrow A along the surface direction, and reference numeral 3 denotes a lower part of the conveyance conveyor 1. The lower surface plate on which the glass substrate W is placed during polishing, the reference numeral 10 is disposed above the lower surface plate 3, and a polishing head for polishing the upper surface of the conveyed glass substrate W, the reference numeral 20 is this A polishing plate serving as an upper surface plate provided in the main body 11 of the polishing head 10.

This polishing machine (portion represented by the polishing head 10) moves the polishing plate 20 in-plane with respect to the glass substrate W while pressing the polishing plate 20 against the surface of the glass substrate W on which the RGB film is formed. Thus, the colored film (RGB film) on the surface of the glass substrate W is polished.
The glass substrate W has a rectangular flat plate shape, and is conveyed from the upstream side to the lower side of the polishing head 10 with one short side at the front end in a posture in which the long side is parallel to the conveyance direction A. While being polished by the polishing head 10, it is conveyed to the downstream side with the same posture and speed.

As shown in FIGS. 3 and 4, a fixed abrasive polishing sheet 23 is attached to the lower surface 20 a (polishing surface 20 a) of the polishing plate 20 with a double-sided tape or the like.
As shown in FIG. 5, the fixed abrasive polishing sheet 23 is composed of a polishing layer 26 made of abrasive grains 27 and a binder resin, and a resin coating layer 24 formed on both upper and lower surfaces of the polishing layer 26. A part of the abrasive grains 27 protrudes only from the outer peripheral portion (side surface) of the polishing layer 26. Further, the edge portion 24a of the resin coating layer 24 is tapered to improve the contact property and slidability with the film surface 200 of the glass substrate W being conveyed.

Here, in the fixed abrasive polishing sheet 23 of the present embodiment, diamond particles having excellent grinding power are used as the abrasive grains (abrasive material particles) 27 that form the polishing layer 26, and a phenol resin is used as the binder resin. . Further, the same phenol resin as the binder resin is used as the resin coating layer 24. By using the same resin material as the polishing layer 26 for the resin coating layer 24, the adhesion between the resin coating layer 24 and the polishing layer 26 can be improved, and both can be firmly fixed.
As the abrasive particles, alumina abrasive grains and the like can be used in addition to the diamond abrasive grains.

  The thickness H2 of the fixed abrasive polishing sheet 23 is set to about 2 mm in consideration of the height of the abnormal protrusion 300 to be polished, the mechanical strength of the polishing sheet, and the like, and the thickness of the resin coating layer 24. H1 is set to about 3 to 5 μm. The particle diameter of the abrasive grains 27 is about 2.5 to 3.0 μm, and the protruding particle diameter of the abrasive grains 27 is 1.0 μm or less.

Here, the thickness H1 of the resin coating layer 24 is set to 3 to 5.0 μm because the thickness H1 of the resin coating layer 24 is smaller than 3 μm from the film surface 200 to the polishing layer 26 of the glass substrate W. Since the distance decreases, the abrasive grains 27 protruding from the side surface of the polishing layer 26 may come into contact with the film surface 200 of the glass substrate W and damage the film surface 200. When the thickness H1 exceeds 5 μm, the film surface 200 This is because the distance of the protruding abrasive grains 27 from the base increases, and it becomes difficult to completely grind the abnormal protrusion 300 on the film surface 200 from the root portion (see FIG. 4).
Incidentally, as shown in FIG. 8, the height S2 of the abnormal protrusion 300 is about 10 to 40 μm, so that it can be sufficiently ground on the side surface of the polishing layer 26 having a thickness of less than 2 mm.

The polishing head 10 is arranged with its own length direction in a direction orthogonal to the conveyance direction A of the glass substrate W, and the length of the polishing head 10 is conveyed on the conveyance path, or the conveyance direction. The length is set such that all of a plurality of (two in the illustrated example) glass substrates W conveyed in a state of being arranged in a direction perpendicular to each other can be polished at a time.
As shown in FIGS. 1 and 6, two fixed abrasive polishing sheets 23 are affixed to the lower surface 20 a of the polishing plate 20 in parallel in the transport direction of the glass substrate W and spaced apart from each other in parallel. In addition, the polishing plate 20 is provided between the two fixed abrasive polishing sheets 23 and is provided with a liquid supply port 13 for supplying pure water to a portion polished by the fixed abrasive polishing sheet 23. .

As shown in FIGS. 3 and 7, the polishing plate 20 is provided on the main body 11 of the polishing head 10 so as to be movable in the vertical direction with the fixed abrasive polishing sheet 23 facing downward.
As shown in FIG. 7, the main body 11 of the polishing head 10 is provided with a pressing chamber 14 having an opening 14 a on the lower surface, and the upper portion of the polishing plate 20 is accommodated inside the pressing chamber 14. The lower part of the polishing plate 20 protrudes downward from the opening 14a. The polishing platen surface 20a on the lower surface of the polishing plate 20 faces the upper surface of the glass substrate W being conveyed.

  Further, a pressurizing tube 18 and a reaction force tube 19 are provided between the main body 11 of the polishing head 10 and the polishing plate 20 to press the polishing plate 20 against the glass substrate W and to adjust the pressing force. It has been.

The pressurizing tube 18 is expanded by introducing pressurized air (a gas other than air may be used) and presses the polishing plate 20 downward, and between the ceiling wall of the pressing chamber 14 and the upper end wall of the polishing plate 20. Is arranged.
The reaction force tube 19 expands by introducing pressurized air (or a gas other than air) and presses the polishing plate 20 upward against the pressure of the pressure tube 18. It is arranged between the flange 25 projecting left and right and the left and right flanges 15 of the opening 14 a on the main body 11 side of the polishing head 10.
FIG. 7B shows the relationship between the downward force P1 caused by the pressurizing tube 18 and the upward force P2 caused by the reaction force tube 19. The pressurizing tube 18 and the reaction force tube 19 are disposed over almost the entire length of the polishing plate 20 in the length direction.

  A pressure adjusting means (not shown) is connected to a pressurized air supply / exhaust pipe (not shown) connected to the pressure tube 18 and the reaction force tube 19. The pressure adjusting means adjusts the pressure balance of the pressurized air introduced into the pressurizing tube 18 and the reaction force tube 19, and the pressure adjusting means, the pressurizing tube 18 and the reaction force tube 19 are used to adjust the glass substrate W. A pressing adjustment mechanism for adjusting the pressing force (that is, polishing pressure) of the polishing plate 20 with respect to is configured.

  In addition, the polishing machine of this embodiment includes at least a motion component in the in-plane direction orthogonal to the conveyance direction of the glass substrate W via the swing shaft 12 protruding from the upper end of the polishing head 10. A drive mechanism (not shown) for orbital movement is provided.

  Next, a method for polishing a film (RGB film) on the surface of the glass substrate W using the polishing machine having the above configuration will be described.

  When the glass substrate W is transported under the polishing head 10 by the transport conveyor 1, as shown in FIG. 7 (b), pressurized air is introduced into the pressurizing tube 18 and also applied to the reaction force tube 19. The compressed air is introduced, the polishing plate 20 is lowered, and the lower surface of the polishing plate 20 is pressed against the film surface 200 of the glass substrate W. At this time, by adjusting the pressure balance between the pressurizing tube 18 and the reaction force tube 19, the pressing force of the polishing plate 20 against the glass substrate W can be set to a suitable value.

  At this time, as shown in FIG. 4, the surface of the fixed abrasive polishing sheet 23 and the film surface 200 of the glass substrate W are completely in contact with each other, and in this state, the polishing head 10 is attached to the glass substrate W. , The film surface 200 of the glass substrate W is polished by the fixed abrasive polishing sheet 23.

  Here, the surface of the fixed abrasive polishing sheet 23 that contacts the glass substrate W is covered with the resin coating layer 24, and the abrasive grains 27 of the polishing layer 26 do not protrude toward the glass substrate W. Even if the grain polishing sheet 23 is in contact with the film surface 200 of the glass substrate W, the film surface 200 is not damaged by the contact of the abrasive grains 27, and the abnormal protrusion 300 on the film surface 200 is formed by the polishing layer. The abrasive grains 27 protruding from the side surfaces 26 are ground from the side.

  Thus, since the surface of the resin coating layer 24 in contact with the film surface 200 of the glass substrate W is not involved in the grinding of the abnormal protrusion 300, the glass substrate set by the pressure tube 18 and the reaction force tube 19 described above. The polishing pressure for W can be reduced as much as possible, and the wear of the resin coating layer 24 due to the contact pressure can be suppressed accordingly. In addition, since the resin coating layer 24 is a phenol resin excellent in wear resistance, the fixed abrasive polishing sheet 23 can maintain a long life from this point.

  As described above, in the polishing machine of this embodiment, the conventional clearance adjustment pad is eliminated, and the entire polishing is performed by directly contacting the fixed abrasive polishing sheet 23 and the glass substrate W. Therefore, the polishing reproducibility is high, and The number of members used can be reduced, and the cost can be reduced.

  Further, by supplying pure water from the liquid supply port 13 to the polishing surface during polishing, polishing debris can be eliminated, so that generation of polishing flaws due to polishing debris can be prevented.

  After the polishing is finished, as shown in FIG. 7A, the pressurized air from the pressure tube 18 is extracted, the pressurized air is introduced into the reaction tube 19, the polishing plate 20 is raised, and the next glass substrate. Prepare for W loading.

  As described above, according to the present polishing machine, it is possible to efficiently remove only the abnormal protrusion 300 without damaging the film surface 200 of the glass substrate W. Therefore, the yield and quality of the product (color filter) can be improved. It can greatly contribute to improvement.

The top view which shows the principal part structure of the manufacturing line of the glass substrate (color filter) equipped with the polisher by embodiment of this invention. The side view which shows the principal part structure of a manufacturing line. Sectional drawing seen from the side of the conveyance direction of the glass substrate which shows the lower part structure of a grinding | polishing plate. The principal part enlarged view which shows a state when pressing a grinding | polishing plate against a glass substrate. It is a figure which shows the structure of an abrasive sheet, (a) is a top view, (b) is a side view. The figure which looked at the polishing plate from the bottom. It is sectional drawing seen from the side of the conveyance direction of the glass substrate which shows the structure of a grinding | polishing head, (a) shows the state before pressing a polishing plate against a glass substrate, (b) presses a polishing plate against a glass substrate. Indicates the state of the Sectional drawing of the color filter for liquid crystal display devices.

Explanation of symbols

1 Transport route (transport conveyor)
DESCRIPTION OF SYMBOLS 3 Lower surface plate 10 Polishing head 11 Main body of polishing head 20 Polishing plate 20a Polishing surface plate surface 23 Polishing sheet 24 Resin coating layer 26 Polishing layer 27 Abrasive grain CF Color filter W Glass substrate

Claims (5)

The surface of the glass substrate is moved by moving the polishing plate in-plane with respect to the glass substrate while pressing the polishing plate having a polishing plate attached to the surface of the glass substrate on which the film is formed. In a polishing machine for polishing the film of the film with the polishing sheet,
The polishing sheet has a polishing layer composed of abrasive grains and a binder resin, and a resin coating layer formed integrally with at least a surface of the polishing layer on the side in contact with the glass substrate, A polishing machine, wherein the abrasive grains protrude from a side surface. The polishing machine according to claim 1, wherein the resin coating layer is made of the binder resin. The polishing machine according to claim 1, wherein the resin coating layer has a thickness of 3 to 5 μm. The lower surface plate on which the glass substrate is placed is disposed below the conveyance path for conveying the glass substrate along the surface direction,
A polishing head for polishing the upper surface of the glass substrate that has been conveyed is provided above the lower surface plate,
In the main body of this polishing head, with the polishing sheet facing downward, the polishing plate as an upper surface plate is provided movably in the vertical direction,
Between the main body of the polishing head and the polishing plate, a pressing adjustment mechanism for pressing the polishing plate against the glass substrate and adjusting the pressing force is provided,
4. The driving mechanism according to claim 1, further comprising an orbital movement that causes the polishing head to include at least a movement component in an in-plane direction orthogonal to a conveyance direction of the glass substrate. A polishing machine according to crab. The polishing machine according to claim 1, wherein the glass substrate is a color filter of a display panel, and the film is an RGB colored film.

Images