KR20090006945A

KR20090006945A - Coating method and apparatus

Info

Publication number: KR20090006945A
Application number: KR1020070070427A
Authority: KR
Inventors: 송민석
Original assignee: 송민석
Priority date: 2007-07-13
Filing date: 2007-07-13
Publication date: 2009-01-16

Abstract

A coating device, and a coating method are provided to prevent or minimize the falling of a coating solution onto a transfer part, thereby inhibiting the contamination of the surface of working product due to the dust generated from the coating solution. A coating device comprises a coating unit(10) which coats a coating solution to the surface of working product; a UV curing part(40) which cures the coating solution coated on the surface of working product with UV rays; a transfer line(50) where a transfer part passing through the UV curing part; and a loading robot(20) which is arranged so as to the working product passed the coating part on the transfer part of the transfer line.

Description

Coating method and apparatus {COATING METHOD AND APPARATUS}

The present invention relates to a coating method and apparatus, and more particularly, to a coating method and apparatus suitable for forming a UV coating layer of a window which is a part of a digital device or an electronic device.

For example, a digital device or an electronic device such as a mobile communication terminal is provided with a display such as an LCD, and the display is protected by a window made of transparent or translucent resin, for example. The surface of such a window is susceptible to external shocks and is susceptible to damage such as scratches.

Accordingly, a protective layer such as a UV coating layer is formed on the surface of the window. In windows for digital devices (or electronics), the UV coating layer increases the surface hardness, in particular the hardness against scratches. For example, the surface hardness value (Brinell hardness value) of the window on which the UV coating layer is formed is much higher than 2 to 3 HB, which is the surface hardness value of the general window on which the UV coating layer is not formed.

Conventional UV coating layer coating method is made by passing a workpiece such as a window continuously through the coating liquid coating portion, the drying portion and the UV curing portion using a conveying portion such as a conveyor. The coating liquid application part applies the coating liquid to the surface of the workpiece, and the drying part dries the coating liquid using, for example, infrared rays of an infrared lamp (IR lamp), and the UV curing part cures the coating liquid.

In the above conventional UV coating method, a significant amount of the coating liquid applied falls on the conveying part, in particular, the circulating conveying part, not the workpiece. The coating liquid dropped to the conveying part is initially cured through the drying part and the UV curing part, but as it accumulates, it is broken and peeled off in a dust form, contaminating the surface of the workpiece conveyed along the conveying part. Contamination of the workpiece surface by dust causes product defects and requires techniques to prevent or reduce the contamination.

The present invention has a technical problem to provide a coating method and apparatus for preventing or minimizing the fall of the coating liquid to the conveying portion for transferring the workpiece, thereby suppressing contamination of the surface of the workpiece by the dust generated from the coating liquid.

According to an aspect of the present invention, there is provided a coating apparatus, comprising: a coating liquid coating unit for applying a coating liquid to a surface of a workpiece; UV curing unit for curing the coating liquid applied to the surface of the workpiece by ultraviolet rays; A transfer line in which a transfer unit passing through the UV curing unit is disposed while being disposed away from the coating liquid applying unit; And a loading robot arranged to transfer the workpiece past the coating liquid application part onto a conveying part on the conveying line.

Preferably, the apparatus further comprises an application stage disposed on the coating solution application unit, wherein the application stage includes a plurality of jigs on which the plurality of workpieces are respectively placed, and the loading robot is configured to include the plurality of workpieces. It is configured to lift from the coating stage and put it on the conveying part.

More preferably, the loading robot includes a finger structure consisting of a plurality of fingers for lifting the plurality of workpieces, each of the plurality of workpieces being shaped to span between two neighboring fingers of the fingers. Has

According to another aspect of the present invention, there is provided a coating apparatus, comprising: a coating liquid coating unit for applying a coating liquid to a surface of a workpiece; UV curing unit for curing the coating liquid applied to the surface of the workpiece by ultraviolet rays; A transfer line having a transfer part passing through the coating liquid coating part and the UV curing part; It is disposed between the coating liquid applying portion and the transfer portion, and includes a coating liquid blocking portion to block the coating liquid leaving the workpiece falling into the transfer portion. The coating liquid blocking unit is arranged to be fixed or movable. Preferably, the workpiece is conveyed seated on a jig on the conveying part.

The transfer line may be further provided with an IR drying unit for drying the coating liquid applied to the workpiece in front of the UV curing unit. The transfer line may have a circular structure, and may further include an unloading robot for lowering the workpiece having passed through the UV curing unit to the outside of the transfer line. The coating liquid coating part may be configured to spray the coating liquid by an inkjet method. The jig has a smaller size than the workpiece so as not to adhere to the coating liquid. Preferably, the workpiece is a resin window of a digital device or an electronic device.

The coating method according to an aspect of the present invention includes the steps of applying a coating liquid to the surface of the workpiece in the coating liquid applying unit; Moving the workpiece away from the coating liquid applying unit to a conveying line arranged; Curing the coating liquid on the surface of the workpiece in the UV curing unit disposed in the transfer line.

According to another aspect of the present invention, there is provided a coating method comprising: applying a coating solution to a surface of a workpiece on a transferring part in a coating liquid applying part disposed in one transfer line; Curing the coating liquid on the surface of the workpiece in the UV curing unit disposed in the transfer line together with the coating liquid coating unit, wherein the coating liquid is applied, the coating liquid disposed between the transfer unit and the coating liquid coating unit Blocking the coating liquid falling out of the workpiece using the blocking unit.

According to embodiments of the present invention, by preventing or minimizing the falling of the coating liquid to the conveying portion for transporting the workpiece, there is an effect of suppressing contamination of the surface of the workpiece by the dust generated from the coating liquid.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

1 is a block diagram for explaining the coating apparatus according to an embodiment of the present invention as a whole.

Referring to FIG. 1, the coating apparatus of the present embodiment includes a coating liquid applying part 10, a UV curing part 40, and the like. In addition, the IR drying unit 30 may be disposed between the coating liquid applying unit 10 and the UV curing unit 40. The coating liquid applying unit 10 is configured to apply the coating liquid to the surface of the window of the digital device, which is the workpiece 2 (see FIG. 2), and the IR drying unit 30 emits infrared rays from the coating liquid applied to the surface of the workpiece 2. It is configured to dry using a lamp. The UV curing unit 40 is configured to cure the coating liquid by ultraviolet irradiation of the UV lamp. In this case, the coating liquid refers to an ultraviolet photosensitive coating liquid which causes a photochemical reaction by the energy of ultraviolet rays and hardens from a liquid phase to a solid phase.

In the present embodiment, the transfer line to which the workpiece 2 is transferred is disposed at the coating stage 50 ′, the IR drying unit 30 and the UV curing unit 40 disposed on the coating liquid applying unit 10. It comprises a conveying line 50, the application stage 50 'and the conveying line 50 is separated. In addition, the transfer line 50 is made of a circular structure that enables a continuous operation. In addition, a cleaning robot 9 may be disposed in front of the coating liquid applying unit 10 for moving the cleaned workpiece to the coating stage before applying the coating liquid.

Due to the separation structure of the application stage 50 'and the transfer line 50, even if the coating liquid falls out of the surface of the workpiece 2 in the coating liquid application part 10, the separated coating liquid remains on the application stage 50'. Only present in the IR drying unit 30 and the UV curing unit 40 does not have any effect on the transfer line 50 is located. This suppresses the generation of dust due to the accumulation of the coating liquid, the repetition of drying and curing, and further, the contamination of the surface of the work piece 2 by the dust.

The coating apparatus of this embodiment includes a loading robot 20 for carrying the workpieces 2 on the coating stage 50 'onto the transfer line 50, as indicated by the dashed arrows. The loading robot 20 serves to transport the workpieces from the application stage 50 'onto a transfer section on the transfer line 50, preferably on a transfer pallet. The workpieces carried on the conveying part of the conveying line 50 circulated continuously pass through the IR drying part 30 and the UV curing part 40 with the coating liquid applied. In addition, the coating device includes an unloading robot 70 for moving the work that has finally passed through the UV curing unit 40, that is, the work on which the coating layer is formed, to a predetermined position from the transfer line 50. can do.

FIG. 2 is a view for explaining the structure of the coating liquid application part 10, the application stage 50 ', and the jig 500 on which the workpiece 2 is seated.

Referring to FIG. 2, the coating liquid applying unit 10 has a structure in which the coating liquid is applied by an inkjet method, and includes a coating liquid reservoir 12 and a nozzle head 14 connected thereto.

The coating liquid reservoir 12 is configured to receive the coating liquid from the coating liquid supply unit 18 connected with the coating liquid tank 17. The coating liquid supply unit 18 supplies the coating liquid in the coating liquid tank 17 to the coating liquid reservoir 12 through a pipe, preferably, a flexible pipe, but a pump driving method or a supply by N ₂ pressure may be used. . In addition, the liquid level sensor 121 is installed in the coating liquid reservoir 12 to keep the coating liquid at a level within a predetermined range.

In addition, the nozzle head 14 is provided with approximately 1 to 1000 coating nozzles, and when a plurality of coating nozzles are provided, the interval between nozzles is approximately 63 μm, but the interval is rotation of the nozzle head or replacement of the nozzle head. It is desirable to be able to correct through. The entire process related to the coating liquid application is performed under the control of the nozzle control unit 19 which is capable of exchanging control signals with the coating liquid applying unit 10. The nozzle control unit 19 controls the spray holding time and the spray interval of the coating liquid. By controlling, the thickness or uniformity of the coating liquid applied to the workpiece can be precisely adjusted. At this time, the coating liquid is preferably applied to the surface of the workpiece to a thickness of 5 ~ 50㎛, more preferably, 10 ~ 20㎛.

The inkjet coating liquid coating structure described above does not use centrifugal force unlike the conventional spin coating method, and thus, the coating liquid film cannot be spread evenly by the centrifugal force, the curved shape, or the workpiece having a hole in the surface. It is possible to apply a uniform coating liquid for the coating liquid, unlike the loss of the coating liquid caused by the centrifugal force of the coating liquid is 80%, there is an advantage that the coating liquid can be applied to the workpiece with only 10% of the coating liquid loss. In addition, there is an additional advantage that the transparent coating liquid can be used for other purposes by replacing it with another coating liquid capable of color printing, so that it is excellent in versatility.

Meanwhile, a coating pallet 52 'is disposed below the coating liquid applying unit 10 on the coating stage 50', and on the coating pallet 52 ', the workpieces 2, that is, for digital devices A plurality of jigs 500 on which the windows are seated are placed. The plurality of jigs 500 are arranged in rows and columns on the application pallet 52 ', and it is preferable that the intervals with other neighboring jigs 500 are always constant. Each of the jig 500 has a wide bottom mounting structure on which the workpiece 2 is seated, and a support 504 built on the application pallet 52 ′ has a narrow upper light narrowing structure, such a jig 500. The shape or structure of the) is to allow the loading robot 20, which will be described in detail below, to easily transport the workpieces 2 on the jig 500 from the application stage 50 ′ to the transfer line 50.

3 is a view for explaining the above-described loading robot 20. As shown in FIG. 3, the loading robot 20 includes a finger structure including a plurality of fingers 22 spaced apart in parallel at regular intervals. And the finger structure is comprised by the drive part 21 so that back and forth can move up and down. The loading robot 20 lifts the plurality of workpieces 2 on the jig 500 using a finger structure and then transfers the lifted workpieces 2 along the transfer line (see FIG. 1). (52), ie on the transfer pallet.

Since the distance between two neighboring fingers 22 of the finger structure is larger than the size of the seating portion 502 of the jig 500 and smaller than the distance of the workpiece 2, the bottom surface of the workpiece 2 is adjacent. It may span between the fingers 22. As mentioned above, in order to transport the plurality of workpieces 2 using the finger structure, the jigs 500 are preferably arranged in rows at predetermined intervals on the application pallet 52 ′.

Referring again to FIG. 1, the processes after coating liquid coating will be described. The workpiece 2 (see FIGS. 2 and 3) transferred from the coating stage 50 ′ to the transfer line 50 is a circular transfer line 50. Moving along, it passes continuously through the IR drying unit 30 and the UV curing unit 40.

The IR drying unit 30 has a structure in which a plurality of infrared lamps (or infrared heaters) are surrounded by a box-shaped wall, and the coating liquid on the workpiece is dried at a temperature of approximately 30 to 80 ° C. The UV curing unit 40 consists of a structure surrounded by a box-shaped wall of one or more UV lamps, further drying the coating solution to sufficiently remove residual liquid components on the coating solution, and at the same time solidifying the solids in the coating solution. Complete the formation process. The workpieces which have passed through the UV curing part 40 are moved from the transfer line 50 to an arbitrary position outside the transfer line 50 by the unloading robot 70.

Although not shown in detail, the transfer line 50 may comprise a roller conveyor, on which the transfer pallet may be fixed or detachably mounted or seated.

A coating apparatus and method according to another embodiment of the present invention will be described with reference to FIGS. 4, 5A and 5B. Compared to the previous embodiment, for the components having the same or similar function, the same reference numerals as used in the previous embodiment are used as they are.

Referring to FIG. 4, the coating liquid coating part 10, the IR drying part 30, and the UV curing part 40 are sequentially disposed in the circulation transfer line 50. Unlike the previous embodiment, as the coating liquid applying unit 10 is disposed in the transfer line 50 where the IR drying unit 30 and the UV curing unit 40 are located, the coating apparatus of the present embodiment is coated liquid coating unit 10 It includes a coating liquid blocking unit 90 to block the coating liquid of the falling to the moving portion on the transfer line (50). The coating liquid blocking unit 90 is integrally or fixedly or mobilely connected to the fixed portion of the transfer line 50, and moved together with the workpiece 2 (see FIGS. 5A and 5B) on the transfer line 50. To prevent the coating from dripping.

5A and 5B, as embodiments of the transfer line 50 described above, one transfer unit 52 and two rails 51 and 51 moving on one rail 51 may be moved. It is shown that the two conveying parts 52, 52 convey the jig 500 and the workpiece 2 seated thereon linearly. At this time, the coating liquid blocking unit 90 is adjacent to the jig 2 and integrally and movably connected to the fixed portion of the transfer line 50, that is, the portion supporting the rail 51, and the workpiece 2. It is located directly below and prevents the coating liquid sprayed from the coating liquid applying unit 10 from falling onto the transfer unit 52.

Therefore, even if the coating liquid sprayed from the coating liquid applying unit 10 falls off the workpiece 2, the coating liquid does not bury or accumulate in the transfer unit 52. This prevents the coating liquid from continuously accumulating in the conveying part regardless of the workpiece 2 and the accumulated coating liquid from curing, peeling and dusting through the IR drying part 30 and the UV curing part 40 repeatedly. To prevent contamination of the workpiece by dust.

Although not shown in detail, the transfer line 50 may include a rail and a timing belt moved by a motor drive along the rail, and the jigs 500 moving along the transfer line 50 may be a workpiece. It is preferable to allow the mounting of the workpiece 2 to a size smaller than the workpiece 2 so as not to be affected by the coating liquid to which (2) is applied.

1 is a block diagram illustrating a coating device according to an embodiment of the present invention.

2 is a view for explaining a part of the coating device shown in FIG.

3 is a view for explaining a loading robot of the coating device shown in FIGS.

Figure 4 is a block diagram illustrating a coating device according to another embodiment of the present invention.

5a and 5b show examples of transfer lines that can be used in the applicator shown in FIG.

10; Coating liquid application part 20: loading robot

30: IR drying part 40: UV curing part

70: unloading robot 90: coating liquid blocking unit

Claims

A coating liquid coating part for applying the coating liquid to the surface of the workpiece;

UV curing unit for curing the coating liquid applied to the surface of the workpiece by ultraviolet rays;

A transfer line in which a transfer unit passing through the UV curing unit is disposed while being disposed away from the coating liquid applying unit; And

And a loading robot arranged to transfer the workpiece past the coating liquid application part onto a conveying part on the conveying line.

The method according to claim 1, further comprising a coating stage disposed on the coating liquid coating unit, a plurality of jigs are disposed on each of the plurality of workpieces are disposed on the coating stage, the loading robot to apply the plurality of workpieces Applicator, characterized in that configured to lift from the stage and put on the conveying portion.

The method of claim 2, wherein the loading robot comprises a finger structure consisting of a plurality of fingers for lifting the plurality of workpieces, wherein the finger is a plurality of workpieces spanning between two neighboring fingers of the fingers; Applicator having a shape.

A transfer line having a transfer part passing through the coating liquid coating part and the UV curing part; And

And a coating liquid blocking unit fixedly disposed between the coating liquid applying unit and the transfer unit to block the coating liquid leaving the workpiece from falling into the transfer unit.

The applicator according to claim 4, wherein the workpiece is conveyed while seated on a jig on the conveying part.

The coating apparatus according to claim 1 or 4, wherein the transfer line further includes an IR drying unit for drying the coating liquid applied to the workpiece in front of the UV curing unit.

The coating apparatus according to claim 1 or 4, wherein the transfer line has a circular structure, and further includes an unloading robot for lowering the workpiece having passed through the UV curing unit to the outside of the transfer line.

The coating apparatus according to claim 1 or 4, wherein the coating liquid applying unit is configured to spray the coating liquid by an inkjet method.

The applicator according to claim 2 or 5, wherein the jig has a size smaller than that of the workpiece so as not to contact the coating liquid.

The coating device according to any one of claims 1 to 6, wherein the workpiece is a window made of a resin material of a digital device or an electronic device.

Applying the coating liquid to the surface of the workpiece in the coating liquid applying unit;

Moving the workpiece away from the coating liquid applying unit to a transfer line arranged; And

And curing the coating liquid on the surface of the workpiece in the UV curing unit disposed in the transfer line.

The method of claim 11, wherein the moving of the workpiece is performed by lifting a plurality of workpieces into a finger structure consisting of a plurality of fingers and then lowering them to another position.

Applying the coating liquid to the surface of the workpiece on the conveying part in the coating liquid applying part disposed in one conveying line; And

Hardening the coating liquid on the surface of the workpiece in the UV curing unit disposed in the transfer line with the coating liquid applying unit,

The applying of the coating liquid, the coating method characterized in that the coating liquid falling off the workpiece using the coating liquid blocking portion disposed between the transfer portion and the coating liquid coating portion.

The coating method according to claim 11 or 13, further comprising drying the coating solution in the IR drying unit disposed in front of the UV curing unit, before the curing step.

The coating method according to claim 11 or 13, wherein the transfer line is circular, and further comprising lowering the workpiece having passed through the UV curing part to the outside of the transfer line.

The coating method according to claim 11 or 13, wherein the coating liquid is sprayed by an inkjet method.

The coating method according to claim 11 or 13, wherein the workpiece is a resin window of a digital device or an electronic device.