TW201435429A - Method of polishing liquid crystal display panels - Google Patents

Abstract

The objective of the present invention is to provide a method for polishing liquid crystal display (LCD) panels that is capable of reducing fragments or damages of large-scale LCD panels, thereby significantly reducing poor displaying quality caused by dimples. The present invention relates to a method for polishing liquid crystal display (LCD) panels, having a step of performing a chemical polishing process on a surface of the LCD panel, the LCD panel being constituted by sandwiching a liquid crystal component in between a first glass substrate having a thin-film transistor layer formed thereon and a second glass substrate having a color filter layer formed thereon, the method of polishing the LCD panel including: an edge-chamfering step to chamfer the edges of the first and second glass substrates prior to the chemical polishing ster; a first glass substrate-mechanically polishing step for performing mechanical polishing to the first glass substrate so that the average diameter of dimples existing on the surface of the first glass substrate is less than 200 μ m after the chemical polishing step is performed; a first residual processing step for removing residuals on the surface of the LCD panel; and a reactive product-removing step for removing reactive produce generated in the chemical polishing step.

Description

Liquid crystal panel polishing method

The present invention relates to a method of polishing a liquid crystal panel.

In recent years, liquid crystal displays (hereinafter referred to as LCDs) have been used as displays for display such as mobile phones, mobile game devices, and mobile terminal devices.

Among these LCDs, a thin film transistor (hereinafter referred to as TFT) type LCD is widely used because of its high definition.

In the TFT-type LCD, a liquid crystal panel is used in which a glass substrate on which a TFT layer is formed and a glass substrate on which a color filter (hereinafter referred to as CF) layer is formed are interposed with a spacer. The liquid crystal member of the spacer is laminated and sealed.

On the other hand, this TFT type LCD has been used in mobile terminal equipment and the like in recent years, and therefore, the demand for thinning has been increasing. In addition, in order to reduce the thickness of the TFT-type LCD, the glass substrate of the main material of the liquid crystal panel of the TFT-type LCD is formed to be thin, so that the entire thickness of the TFT-type LCD can be reduced.

In order to reduce the thickness of the glass substrate used in the liquid crystal panel In the method, a chemical polishing method in which the entire surface of the liquid crystal panel or a single surface is immersed in a polishing liquid such as hydrofluoric acid to polish the surface of the glass substrate is generally used.

However, in the chemical polishing method by the immersion, there may be a case where dimples or reaction products are formed on the surface of the polished glass substrate.

The pit is a pit which appears in a dot shape or a row on the surface of the glass substrate after the chemical polishing, and is a flaw or a micropore which is present on the surface of the glass substrate before chemical polishing and is enlarged by chemical polishing to be detected. Out of the hollow.

Further, the component contained in the glass substrate material of the reaction product is reacted with the chemical polishing liquid or the component dissolved in the chemical polishing liquid, which is fixed to the surface of the glass.

In addition, when a TFT-type LCD is manufactured using such a liquid crystal panel in which pits are formed or a reaction product is fixed, a display defect called a bright spot due to a pit or a reaction product is generated. Fixation causes deterioration in film properties, display failure, or loss of touch panel.

Heretofore, as a method of eliminating the pits, a method of mechanically polishing the surface of the glass substrate before chemical polishing in order to eliminate scratches or fine pores which are caused by pits is known (refer to, for example, Patent Document 1) ).

However, this method is only for the purpose of suppressing pits, and is not intended to suppress the fixation of the reaction product due to chemical polishing. Therefore, it is impossible to solve the display failure caused by the reaction product or even the lack of the touch panel.

On the other hand, the liquid crystal panel is generally cut into a large-sized liquid crystal panel of about G5 (1200 mm × 1000 mm) of the specification indicated by G (generation), and the screen size of the final product is created.

In this case, when a large liquid crystal panel is processed at a manufacturing site, debris on the side surface of the liquid crystal panel or damage of the liquid crystal panel itself occurs. Furthermore, the chipping or breakage of such a liquid crystal panel causes a decrease in yield, which causes a rise in manufacturing cost.

In addition, in the conventional manufacturing site of a liquid crystal panel, measures for causing chipping or breakage when handling such a large liquid crystal panel of about G5 are not considered.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2003-15111

In view of the above circumstances, in order to solve the conventional problems, an object of the present invention is to provide a method for reducing the occurrence of chipping or breakage of a large liquid crystal panel, and to greatly suppress the occurrence of pits and the fixation of the reaction product. A method of polishing a liquid crystal panel with a defect or the like.

That is, the characteristics of the liquid crystal panel polishing method of the present invention as follows.

First, a liquid crystal panel polishing method includes a chemical polishing step of performing chemical polishing on a surface of a liquid crystal panel, wherein the liquid crystal panel is a first glass substrate on which a TFT layer is formed and a second glass on which a color filter layer is formed. a liquid crystal member is interposed between the substrates, and the liquid crystal panel polishing method has the following steps: a chamfering step of performing chamfering of the first and second glass substrates of the liquid crystal panel before the chemical polishing step; In the glass substrate mechanical polishing step, the first glass substrate is mechanically polished so that the average diameter of the pits existing on the surface of the first glass substrate after the chemical polishing step is 200 μm or less; and the first residue processing step is as described above. The residue on the surface of the liquid crystal panel is removed; and the reaction product removal step is performed, and after the chemical polishing step, the reaction product generated in the chemical polishing step is removed.

Secondly, in the first liquid crystal panel polishing method, the second glass substrate mechanical polishing step is performed to mechanically polish the second glass substrate so that the surface of the second glass substrate after the chemical polishing step is present The average diameter of the pits is 50 μm or less; and the second residue treatment step removes the residue on the surface of the liquid crystal panel and the reaction product generated in the chemical polishing step.

According to the first aspect of the invention, the chamfering step of performing chamfering of the first and second glass substrates of the liquid crystal panel is performed before the chemical polishing step, and mechanical polishing of the first glass substrate is performed to cause the chemical polishing step. The average of the pits present on the surface of the first glass substrate The first glass substrate mechanical polishing step having a diameter of 200 μm or less and the first residue treatment step for removing the residue on the surface of the liquid crystal panel, and after the chemical polishing step, a reaction product removing step is provided to provide a reduction in large liquid crystal A liquid crystal panel polishing method in which a reaction product adhering to the surface of the liquid crystal panel can be removed by a chemical polishing step by suppressing occurrence of chipping or breakage of the panel and greatly suppressing display defects caused by the occurrence of pits.

According to the second aspect of the invention, the second glass substrate mechanical polishing step of the second glass substrate after the chemical polishing step is 50 μm or less, and the mechanical polishing of the second glass substrate is performed. The second residue treatment step of removing the residue on the surface of the liquid crystal panel and the reaction product generated in the chemical polishing step can provide an effect of the first invention in addition to the effect of the first invention. A liquid crystal panel polishing method which causes display failure.

1‧‧‧1st glass substrate

2‧‧‧2nd glass substrate

3‧‧‧Liquid crystal components

4‧‧‧ Sealing material

11‧‧‧TFT layer

12‧‧‧ surface

21‧‧‧CF layer

22‧‧‧ Surface

31‧‧‧ spacers

S1‧‧‧Chamfering step

S2‧‧‧First Glass Substrate Mechanical Grinding Step

S3‧‧‧1st residue treatment step

S4‧‧‧ chemical grinding step

S5‧‧‧Reaction product removal step

S6‧‧‧2nd glass substrate mechanical grinding step

S7‧‧‧Second residue treatment steps

Fig. 1 is a schematic cross-sectional view showing the configuration of a liquid crystal panel.

Fig. 2 is a flow chart showing an embodiment of a method for polishing a liquid crystal panel of the present invention.

Fig. 3 is a flow chart showing another embodiment of the liquid crystal panel polishing method of the present invention.

Fig. 4(a) is a schematic view showing a polishing shape of a corner portion viewed from above, and Fig. 4(b) is a view showing a grinding shape of a side surface viewed from the side. An overview of the state.

The liquid crystal panel polishing method of the present invention is a liquid crystal panel polishing method for polishing the surface of the liquid crystal panel having the configuration shown in Fig. 1.

In the liquid crystal panel, the liquid crystal member 3 and the spacer 31 are sandwiched between the first glass substrate 1 and the second glass substrate 2, and the edge portion is sealed by the sealing member 4.

The first glass substrate 1 has a TFT layer 11 formed on the liquid crystal member 3 side, and the second glass substrate 2 has a CF layer 21 formed on the liquid crystal member 3 side.

The liquid crystal panel polishing method of the present invention relates to a method of polishing the surface of the liquid crystal panel, that is, the surface of the glass substrate 11 on which the TFT layer 11 and the CF layer 21 are not formed.

The liquid crystal panel polishing method of the present invention will be described in detail below using a flowchart. Fig. 2 is a flow chart showing an embodiment of a method for polishing a liquid crystal panel of the present invention.

In the liquid crystal panel polishing method of the present embodiment, the chamfering step (S1), the first glass substrate mechanical polishing step (S2), the first residue processing step (S3), the chemical polishing step (S4), and the reaction generation are performed. The step of removing the step (S5).

The size of the liquid crystal panel which is suitable for the liquid crystal panel polishing method of the present invention is generally about the size of G5 (1200 mm × 1000 mm) of a large liquid crystal panel which is expressed by G.

In the LCD panel of the G5 size, it is usually very difficult The display failure or the like due to the generation of pits or the adhesion of the reaction product is suppressed, and the damage caused by the occurrence of chips or cracks in the polishing step or the like is large.

Therefore, the series of steps from the chamfering step (S1) to the reaction product removing step (S5) of the liquid crystal panel polishing method of the present invention described below is extremely important, and by these steps, high quality can be produced with better yield. LCD panel.

<Chamfering step (S1)>

In the liquid crystal panel polishing method of the present invention, first, the chamfering of the corner portions of the corner portion and the side surface portion of the liquid crystal panel is performed by the chamfering step (S1).

The chamfering condition is not particularly limited as long as it does not affect the function of the LCD of the final product, and liquid crystal can be performed by a polishing device provided in the middle portion of the conveyance path of the liquid crystal panel. Grinding of the corner and edge of the panel.

The grinding of the corner portion can be performed, for example, by using a rotating diamond of a metal bond of diamond size #300 to 600, and forming a shape of 1C to 5C or 1R to 5R in the cut shape shown in Fig. 4(a). R is in accordance with the Japanese Industrial Standard JISB001:2010).

Further, the chamfering of the side surface portion can be, for example, a rotating grindstone of a metal bond of diamond size #300 to 600, and a chamfer width of 0.1 mm or more and a face shape C can be obtained in the cut shape shown in Fig. 4(b). Or R (C and R are in accordance with Japanese Industrial Standard JISB001:2010).

The grinding of the corner portion and the side portion described above is one side The liquid crystal panel is transported by a polishing apparatus, but the transport conditions and the operating conditions of the polishing apparatus can be appropriately set in accordance with the size, material, and the like of the liquid crystal panel to be introduced.

By chamfering the liquid crystal panel under the above conditions, the strength of the corner portion and the side portion with respect to the mechanical impact can be jumped off, and the chipping or breakage of the liquid crystal panel in the subsequent steps can be greatly reduced.

Further, in this chamfering step, the dirt on the surface of the ground glass frit or the glass substrate is washed and removed by a washing and drying step after chamfering, and dried.

The conditions for washing and drying are not particularly limited as long as the conditions for removing the stain on the surface of the glass frit or the glass substrate are removed. However, the cleaning can be performed by, for example, transporting the liquid crystal panel to the upper and lower surfaces of the liquid crystal panel. It is made up of a disk brush such as nylon or a roll brush made of nylon or the like and water.

Further, the drying system can be carried out, for example, by using a dewatering drum made of PVA (Polyvinyl Alcohol) or the like, an air knife, a warm air dryer, or the like.

<First Glass Substrate Mechanical Polishing Step (S2)>

Next, a first glass substrate mechanical polishing step (S2) of mechanically polishing the surface of the first glass substrate on which the TFT layer is formed is performed.

In the polishing machine used in the first glass substrate mechanical polishing step (S2), a generally known automatic mechanical polishing machine using a polishing pad and a polishing material can be suitably used. For example, a material can be used. A polishing pad such as a polyurethane or a polishing material such as celite is used.

By performing the first glass substrate mechanical polishing step (S2) before the chemical polishing step (S4) to be described later, the scratches or fine pores on the surface of the first glass substrate on which the TFT layer is formed are removed in advance, whereby chemical polishing can be performed. The average diameter of the pits present on the surface of the first glass substrate after the step is suppressed to 200 μm or less, preferably 50 μm or less. Further, the average diameter of the pit of the present invention means the diameter of the pit.

In the first glass substrate mechanical polishing step of the liquid crystal panel polishing method of the present invention, the reason why the surface of the first glass substrate on which the TFT layer is formed is polished is due to display failure due to the occurrence of pits. It is derived from the pits generated on the surface of the first glass substrate on which the TFT layer is formed.

In this case, since the first glass substrate on which the TFT layer is formed is considered to be a backlight side, for example, the pits on the surface of the first glass substrate on which the TFT layer is formed function as a concave lens, and the diffuse reflection from the backlight is performed here. The light spreads and becomes a bad display such as a bright spot.

Therefore, in the present invention, the first glass substrate mechanical polishing step (S2) in which the surface of the first glass substrate on which the TFT layer is formed is mechanically polished is a particularly important step.

<First residue processing step (S3)>

In the liquid crystal panel polishing method of the present invention, after the first glass substrate mechanical polishing step (S2), the first residue processing step (S3) is performed.

This first residue treatment step (S3) is used to The steps of removing the polishing glass powder or the polishing material, and preventing the scrubbing treatment of the polishing material generated on the surface of the second glass substrate, and the washing and drying treatment.

The conditions of the washing treatment are not particularly limited as long as the ground glass powder or the abrasive material can be removed. For example, in the upper and lower surfaces of the liquid crystal panel, calcium carbonate or cerium oxide can be used as the abrasive material, and a disc sponge made of PVA or the like can be used. Disk sponge) for washing.

Further, the washing system can be carried out, for example, by using a roller brush made of nylon or the like and water.

Further, the drying system can be carried out, for example, using a dewatering drum made of a PVA sponge or the like, an air knife, a warm air dryer, or the like.

By performing the first residue treatment step (S3), it is possible to form a liquid crystal which is free from scratches or fine pores which are caused by pits on the TFT side surface of the liquid crystal panel, and which is cleaned by residue due to polishing. panel.

<Chemical Grinding Step (S4)>

Next, a chemical polishing step (S4) is performed. This chemical polishing step (S4) can be carried out by a chemical polishing method generally performed to thin the liquid crystal panel.

In this chemical polishing method, the entire liquid crystal panel is immersed in a polishing liquid to polish the surfaces of the first and second glass substrates. The polishing liquid may, for example, be hydrofluoric acid or the like which is usually used in chemical polishing, and the polishing conditions may be appropriately set in consideration of the thickness of the final liquid crystal panel.

Further, after chemical polishing, a washing and drying step for removing the polishing liquid is performed.

<Reaction product removal step (S5)>

Next, in the polishing method of the liquid crystal panel of the present invention, the reaction product removal step (S5) is carried out for the purpose of removing the reaction product which is generated by the chemical polishing step (S4).

The reaction product produced in the chemical polishing step is usually a substance produced by reacting hydrofluoric acid used as a polishing liquid in chemical polishing with a material component of a liquid crystal panel polished by the polishing liquid.

The material component of the liquid crystal panel which is a cause of the reaction product is a material such as Al, Ca, Mg, or Sr contained in the glass composition, and a sealing material or a substrate at the edge of the liquid crystal panel, and between the glass and the substrate. Examples of the binder component, etc., specific examples of the reaction product include aluminum fluoride (AlF ₃ ), magnesium fluoride (MgF ₂ ), calcium fluoride (CaF ₂ ), cesium fluoride (SiF ₄ ), and the like. Inorganic fluorides, or inorganic, organic complexes, and the like. In addition, it is also included in the polishing liquid, such as bismuth (Si), which is fixed on the glass substrate.

These reaction products adhered to the surface of the glass substrate are responsible for display failure or loss of the touch panel.

This reaction product removal step (S5) is performed on both surfaces of the first glass substrate and the second glass substrate.

The condition of the reaction product removal step (S5) is not particularly limited as long as the reaction product can be completely removed. However, for the scrubbing treatment, for example, calcium carbonate or cerium oxide can be used as the polishing material, and the material is PVA or the like. The disc sponge is coming.

Further, the washing system can be carried out, for example, by using a roller brush made of nylon or the like and using water.

Further, the drying system can be carried out, for example, using a dewatering drum made of a PVA sponge or the like, an air knife, a warm air dryer, or the like.

By performing this reaction product removing step (S5), it is possible to manufacture a clean liquid crystal panel having no pits as a whole in the liquid crystal panel.

Next, another embodiment of the liquid crystal panel polishing method of the present invention will be described in detail using the flowchart of Fig. 3.

In the liquid crystal panel polishing method of the present embodiment, the chamfering step (S1), the first glass substrate mechanical polishing step (S2), the first residue processing step (S3), the chemical polishing step (S4), and the second glass are provided. The substrate mechanical polishing step (S6) and the second residue processing step (S7).

In the present embodiment, each step from the chamfering step (S1) to the chemical polishing step (S4) is performed from the chamfering step (S1) to the chemical polishing step in the embodiment shown in Fig. 2 described earlier. The steps of (S4) are the same steps, and the description thereof will be omitted.

<Second Glass Substrate Mechanical Polishing Step (S6)>

In the liquid crystal panel polishing method of the present invention, the second glass substrate mechanical polishing step (S6) can be performed for the purpose of removing pits which may occur on the surface of the second glass substrate on which the CF layer of the liquid crystal panel is formed.

In the second glass substrate mechanical polishing step (S6), the same automatic mechanical polishing machine as that used in the first glass substrate mechanical polishing step (S2) can be suitably used. In terms of polishing conditions, for example, a polishing pad made of foamed polyurethane or the like can be used, and the material is oxidized. Grinding materials such as enamel are used.

As described above, by performing the second glass substrate mechanical polishing step (S6) after the chemical polishing step (S4), the average diameter of the pits existing on the surface of the second glass substrate after the chemical polishing step can be suppressed to 50 μm. Hereinafter, it is preferably 30 μm or less.

<Second residue processing step (S7)>

In the liquid crystal panel polishing method of the present invention, after the second glass substrate mechanical polishing step (S6), the second residue processing step (S7) is performed.

The second residue treatment step (S7) includes removing the ground glass frit or the abrasive material after the polishing by the second glass substrate mechanical polishing step (S6), and removing the generated in the chemical polishing step (S4). The step of removing the reaction product for the purpose of the reaction product to be fixed, and the step of the step of washing, washing, and drying.

This second residue treatment step (S7) is performed on both surfaces of the first glass substrate and the second glass substrate.

The washing treatment is not particularly limited as long as the ground glass frit, the polishing material, and the reaction product can be removed. For example, calcium carbonate or cerium oxide can be used as the polishing material, and a disc sponge made of PVA or the like can be used.

Further, the washing system can be carried out, for example, by using a roller brush made of nylon or the like and using water.

Further, the drying system can be carried out, for example, using a dewatering drum made of a PVA sponge or the like, an air knife, a warm air dryer, or the like.

By performing the second residue treatment step (S7), the ground glass frit, the abrasive, and the reaction product can be removed, and the liquid crystal panel can be manufactured. A clean liquid crystal panel with no residue on the surface.

In the above, the liquid crystal panel polishing method of the present invention has been described with reference to the embodiments, but the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit and scope of the invention.

For example, in the above-described embodiment, in the first glass substrate mechanical polishing step (S2), only the surface of the first glass substrate on which the TFT layer is formed is mechanically polished, but in this step, it may be formed. The surface of the first glass substrate of the TFT layer is simultaneously or separately mechanically polished on the surface of the second glass substrate on which the CF layer is formed.

For example, by performing the chamfering step (S1) after the chemical polishing step (S4), the strength of the corner portion and the side portion of the liquid crystal panel damaged by the chemical polishing step (S4) can be improved.

Further, in the above-described embodiment, the liquid crystal panel which can be suitably used in the liquid crystal panel polishing method according to the present invention has a size of about G5 (1200 mm × 1000 mm), but it is of course possible to correspond to a panel size of G5 or less ( G1 (400 mm × 300 mm) to G4.5 (920 mm × 730 mm), and may also correspond to a size of G5.5 (1500 mm × 1300 mm) or more.

S1‧‧‧Chamfering step

S2‧‧‧First Glass Substrate Mechanical Grinding Step

S3‧‧‧1st residue treatment step

S4‧‧‧ chemical grinding step

S5‧‧‧Reaction product removal step

Claims (2)

A liquid crystal panel polishing method comprising a chemical polishing step of performing chemical polishing on a surface of a liquid crystal panel, wherein the liquid crystal panel is a first glass substrate on which a thin film transistor layer is formed and a second glass substrate on which a color filter layer is formed The liquid crystal panel polishing method has the following steps: a chamfering step of performing chamfering of the first and second glass substrates of the liquid crystal panel before the chemical polishing step; first glass In the substrate mechanical polishing step, the first glass substrate is mechanically polished so that the average diameter of the pits existing on the surface of the first glass substrate after the chemical polishing step is 200 μm or less; and the first residue treatment step is performed on the liquid crystal. The residue on the surface of the panel is removed; and the reaction product removal step is performed, after the chemical polishing step, the reaction product generated in the chemical polishing step is removed. The liquid crystal panel polishing method according to claim 1, further comprising: a second glass substrate mechanical polishing step of performing mechanical polishing on the second glass substrate to cause the second glass substrate after the chemical polishing step The average diameter of the pits present on the surface is 50 μm or less; and the second residue treatment step removes the residue on the surface of the liquid crystal panel and the reaction product generated in the chemical polishing step. except.