KR20060100008A - Mehtod of die coating for getting many faces - Google Patents

Abstract

The present invention relates to a multi-faceted die coating method for coating by having a plurality of coating surfaces on a single substrate, and more particularly, in the coating end section of the coating surface pre-coated among the plurality of coating surfaces. Inhalation of the coating liquid remaining inside the slit die prevents the thickness of the coating layer at the beginning of the coated surface being thickened at the same time, and at the same time, the internal residual pressure of the slit die to which the coating liquid is supplied is eliminated to minimize the uneven area of the coating surface To a multi-faceted die coating method.

Face Lift, Die Coating, Syringe Pump

Description

Method of die coating for getting many faces}

1 is a schematic configuration diagram of a coating apparatus with a slit die;

Figure 2a is a running speed graph of the slit die according to the multi-faceted die coating method according to the present invention.

Figure 2b is a graph of the suction and discharge amount of the pump according to the multi-sided die coating method according to the present invention.

3 is a process flowchart of a multi-faceted die coating method according to the present invention.

4A and 4B are graphs showing the thickness of the initial coating layer after the initial coating surface;

Figure 4a is a graph of the thickness of the coating film according to the prior art.

Figure 4b is a graph of the thickness of the coating film formed on the coating surface by the present invention.

<Description of Symbols for Main Parts of Drawings>

2 ; Substrate 10; Slit die

26; Pump

s1, s2, s3; Coating initial f1, f2, f3; Coating finish section

The present invention relates to a multi-faceted die coating method for coating with a plurality of coating surfaces on a single substrate, and more particularly, to remain inside the slit die at the coating end section of the coating surface to be pre-coated. By inhaling the coating liquid, the thickness of the coating layer at the beginning of the after-coating surface is prevented from becoming thick, and at the same time, the internal pressure of the slit die to which the coating liquid is supplied is removed to minimize the uneven area of the coating surface. It is about a method.

In general, a method of coating a substrate by a slit die is an apparatus used to form a film having a uniform thickness by discharging and applying a predetermined amount of coating liquid onto a substrate, such as photoresist coating.

In this die coating method, as shown in FIG. 1, the substrate 2 is mounted on the stone plate 20 at the lower portion of the slit die 10, and the die of the slit die 10 is mounted on the substrate 2. A film having a predetermined thickness is formed while discharging the coating liquid through the die lip 12 opened in the long side direction of the slit die 10 on the lip surface. In this case, the slit die 10 is coated on the substrate 2 while being moved horizontally by the X-axis driver 22, the Y-axis driver (not shown), or the Z-axis driver 24. The slit die 10 is connected to a supply means such as a pump system 26 to continuously supply the coating liquid through the coating liquid supply line 28.

As described above, after the coating operation by the sliding operation of the slit die 10, the coating liquid remains on the die lip surface 12 of the slit die 10, this coating liquid is removed using a cleaning device. As described above, since the coating liquid remaining on the die lip surface of the slit die is removed after one coating is performed, there is no problem due to the remaining coating liquid treatment.

However, recently, as the substrate is enlarged, a multi-faceted method of coating two or more sheets sequentially is applied. Step coating is performed due to the application of the multifaceted method. In this step coating, the coating liquid remains on the die lip surface of the slit die after coating the surface to be coated on the first substrate. In this case, the film thickness at the beginning becomes thicker, resulting in a problem that the uneven area becomes large.

In order to solve this problem, conventionally, a bypass valve is used to reduce the amount of coating liquid remaining on the slit die's die lip surface. However, there is a limit to reducing coating liquid using only a bypass valve. In the case of performing two or more coating operations, there is a problem that the coating surface after the initial coating target surface does not reduce the non-uniform area of the initial coating film.

The object of the present invention devised in view of such a problem is that the area in which the initial coating layer of the coating surface is unevenly coated after the first coating surface in the process of sequentially step coating a plurality of coating surfaces provided according to the enlargement of the substrate By minimizing the overall thickness uniformity of the coating surface is to be improved.

Another object of the present invention is to reduce the internal residual pressure of the slit die to reduce the non-uniform area of the coating film when coating by the slit die compared to the residual pressure removing method using a conventional bypass valve.

The present invention for achieving the technical problem as described above, the slit die horizontally moved on the substrate by coating the plurality of coating surfaces provided on the substrate by the slit die which is supplied with a coating liquid by a pump in order to multi-faceted In the die coating method, the slit die is slid at a constant running speed in the interval from the beginning of the coating to the end of the coating of the coating surface of the coating surface, the first coating for coating while discharging a predetermined amount of coating liquid in the pump step; A second coating step in which the pump performs coating while sucking the coating liquid from the slit die at the coating end section of the coating surface; and the respective coating surfaces entering the traveling path of the slit die horizontally moved on the substrate; It provides a multi-faceted die coating method comprising the step of repeating the first and second coating step for.

In addition, it is preferable that the pump performs coating while sucking the coating liquid from the slit die while reducing the traveling speed of the slit die in the second coating step.

In addition, it is preferable that the pump discharges the coating liquid into the inside of the slit die by using a syringe pump or sucks the coating liquid into the inside of the slit die.

Hereinafter, preferred embodiments of the present invention as described above will be described in more detail with reference to the accompanying drawings.

The present invention is to minimize the non-uniform area of the first coating layer of the coating surfaces to be carried out after the initial coating surface while performing the step coating for multi-sided production during coating of the substrate by the slit die, referring to FIG. The substrate 2 is mounted to the stone plate 20 at the lower portion of the 10, and is opened in the long side direction of the slit die 10 on the die lip surface of the slit die 10 on the substrate 2. The coating liquid is discharged through the die lip 12 to form a film having a predetermined thickness. In this case, the slit die 10 is coated on the substrate 2 while being moved in the horizontal direction by the X-axis driver 22 or the Y-axis driver.

The slit die 10 is connected to a supply means such as a pump system 26, wherein the pump system according to the present invention uses a syringe type pump system to accurately discharge the coating liquid and suckback. )

The coating method by the slit die according to the present invention is to control the running speed of the slit die, the discharge and suction amount of the syringe pump in the coating section of the coating surface.

Figure 2a is a running speed graph of the slit die according to the present invention, Figure 2b is a coating liquid discharge amount graph of the syringe pump according to the present invention.

As shown in FIG. 2A, the slit die that travels at a constant speed from the initial time of coating (s1, s2, s3) to a predetermined section on each coating surface (in the embodiment, one sheet, two sheets, and three sheets are shown) The running speed is reduced in the coating end sections f1, f2 and f3.

In addition, as shown in Figure 2b, in the syringe pump that discharged a certain amount of coating liquid from the initial coating time (s1, s2, s3) to a predetermined section to suck the coating liquid of the slit die in the coating end section (f1, f2, f3) do.

That is, when the present invention is described with reference to FIG. 3, the slit die is slid at a constant traveling speed in a section from each coating surface provided on the substrate to a coating end section f1, f2, and f3 before the coating end section. In the syringe pump, a first coating step of applying a coating while discharging a predetermined amount of coating liquid is performed first.

Subsequently, in the coating end sections f1, f2, and f3 of the coating surface, the running speed of the slit die is reduced, and the syringe pump performs a second coating step of coating while sucking the coating liquid from the slit die. .

Then, the first coating step and the second coating step are repeatedly performed on the respective coating surfaces that enter the traveling path of the slit die continuously moved on the substrate.

At this time, the coating end section set on the coating surface is different depending on the size of the coating surface of the substrate to be coated, but the size of the coating liquid is not excessively discharged at the beginning of the next coating surface experimentally by suction of the coating liquid by the syringe pump. Set the interval of. Therefore, the suction operation by the syringe pump is performed at an appropriate time within the coating end section.

As described above, the present invention reduces the running speed of the slit die at the coating end section f1 of the coating surface during the first coating, and absorbs the coating liquid from the syringe pump, thereby remaining the chemical liquid (coating liquid) remaining on the die lip surface of the slit die. At the beginning of the second coating surface, the excessive coating liquid is not discharged through the die lip of the slit die, and repeatedly the running speed of the slit die is reduced at the coating end section f2 of the two coating surfaces. In the syringe pump, the coating liquid is absorbed to minimize the coating liquid in the slit die so that the coating liquid is not excessively discharged at the beginning of the third coating surface.

As the slit die is horizontally moved, the slit die is slid at a normal running speed for a predetermined period at the time of initial coating (s1, s2, s3) for each coating surface entering the movement path of the slit die, and the syringe pump Coating is performed while the coating liquid is normally discharged through the coating liquid. When the coating ends are entered into the coating end sections f1, f2, and f3 of the coating surface, the syringe pump decelerates the running speed of the slit die while remaining in the slit die. This will reduce the thickness of the first coating layer of the coating surface is then coated.

Figure 4a is a graph showing the coating liquid thickness of the conventional coating state by the pump system, Figure 4b is a graph showing the coating liquid thickness of the suction is performed by the syringe pump according to the present invention.

Therefore, while the thickness of the first coating film in the second sheet is more than 120% of the thickness of the entire coating film is reduced to 110% or less in the present invention, and the non-uniform area of the coating film is conventionally generated more than 30mm, in the present invention less than 10mm It can be seen experimentally that it has been reduced to the area of.

 As described above, the present invention is not limited to the above-described embodiments, and any person having ordinary knowledge in the technical field to which the present invention belongs without departing from the gist of the present invention claimed in the claims. It is to be understood that such modifications are possible, and such changes are within the scope of the claims.

As described above, the present invention is to reduce the running speed of the slit die at the start of the section to finish the coating of each coating surface during the multi-face die die coating, and also by sucking the coating liquid by the pump system in the coating end section Minimizing the chemical liquid on the die lip surface of the slit die has the effect of ensuring the overall uniformity of the coating surface.

In addition, the present invention can easily remove the internal residual pressure of the slit die to eliminate the separate bypass valve, there is an effect that can reduce the non-uniform area at the coating end position than the residual pressure removing method using a conventional bypass valve. .

Claims (3)

In the multi-sided die coating method of sequentially coating a plurality of coating surfaces provided on the substrate by the slit die receiving the coating liquid by the pump while the slit die is horizontally moved on the substrate, A first coating step in which the slit die is slid at a predetermined traveling speed in a section of the coating section of the coating surface from the beginning of the coating to the end of the coating section, and the pump performs coating while discharging a predetermined amount of the coating liquid; A second coating step in which the pump performs coating while sucking the coating liquid from the slit die within the coating end section of the coating surface; and And repeating the first and second coating steps for the respective coating surfaces entering the travel path of the slit die horizontally moved on the substrate. The method of claim 1, And the pump performs coating while sucking the coating liquid from the slit die while reducing the traveling speed of the slit die in the second coating step.  The method according to claim 1 or 2, And the pump discharges the coating liquid into the slit die by using a syringe pump or sucks the coating liquid into the slit die.

Images