KR20100128897A - Forming method of print pattern - Google Patents

Abstract

PURPOSE: A method for forming printing patterns is provided to easily form minute printing patterns and to simplify a process compared to photolithography. CONSTITUTION: A method for forming printing patterns is as follows. Paste is spread on an object in specific patterns(161) using an offset printing method. Temporary patterns(16) are formed by hardening the spread paste. The width of the temporary patterns is reduced by cutting the surface of the temporary patterns. Printing patterns are formed by plasticizing the temporary patterns.

Description

How to Form a Print Pattern {FORMING METHOD OF PRINT PATTERN}

The present invention relates to a printing pattern forming method, and more particularly, to a printing pattern forming method capable of forming a fine width printing pattern.

Off-set printing methods are widely used to form electrodes of display devices, for example, electrodes of plasma display panels, mesh-type shielding members of electromagnetic wave shielding filters, and spacers of liquid crystal display devices. .

In the offset printing method, the paste is accommodated in the groove of the gravure roll, and the paste is removed from the gravure roll using a blanket roll, which is an intermediate medium, and then printed on the printed matter. In such an offset printing method, it is difficult to implement a fine pattern due to the groove processing limit of the gravure roll and the viscoelastic properties of the paste.

Another object of the present invention is to provide a printing pattern forming method capable of easily forming a fine width printing pattern while using an offset printing method having a relatively low process cost.

The printing pattern forming method according to an embodiment of the present invention comprises the steps of: i) applying a paste on a to-be-printed object in a specific pattern; ii) curing the applied paste to form a temporary pattern; Cutting the surface to reduce the width of the temporary pattern; and iii) firing the temporary pattern to form a printed pattern.

In the step of applying the paste, the paste may be applied by offset printing. The paste may comprise a conductive material and a glass frit.

In the step of forming the temporary pattern, the paste may be cured by any one of exposure, drying, and thermal curing. The temporary pattern may be formed in a convex shape toward a direction away from the to-be-printed object.

In the step of reducing the width of the temporary pattern, the temporary pattern may be shaved by a chemical reaction with the developer. Assuming that the width of the temporary pattern measured before the step of reducing the width of the temporary pattern is 1, the ratio of the width of the printed pattern to the width of the temporary pattern may be 0.05 to 0.95.

The printing pattern may be used as any one of an electrode of a display device, a mesh-type shielding member of an electromagnetic wave shielding filter, a spacer of a liquid crystal display device, and a radio frequency identification (RFID) tag.

Compared with the pattern formation method, which is complicated and has high process cost, such as photolithography, the process can be simplified, the process cost can be reduced, and fine printing patterns having a width of several μm to 20 μm can be easily formed.

DETAILED DESCRIPTION Embodiments of the present invention will be described with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As can be easily understood by those of ordinary skill in the art to which the present invention pertains, the following embodiments are only intended to illustrate the present invention, and various forms without departing from the spirit and scope of the present invention. It can be modified.

All terms including technical terms and scientific terms used hereinafter have the same meaning as commonly understood by one of ordinary skill in the art. Terms defined in advance are further interpreted to have a meaning consistent with the related technical literature and the presently disclosed contents, and are not interpreted in an ideal or very formal sense unless defined.

1 is a process flowchart showing a printing pattern forming method according to an embodiment of the present invention.

Referring to FIG. 1, the printing pattern forming method may include a first step S100 of applying a paste on a to-be-printed object in a specific pattern, a second step S200 of curing the applied paste to form a temporary pattern, and a temporary A third step (S300) of cutting the surface of the pattern to reduce the width of the temporary pattern, and a fourth step (S400) of firing the temporary pattern to form a printed pattern.

FIG. 2 is a schematic cross-sectional view showing the paste of the first step S100 shown in FIG. Referring to FIG. 2, an offset printing apparatus may be used to apply the paste 12 in the first step S100.

The offset printing apparatus (not shown) may include a dispenser for discharging the paste, a gravure roll for forming a groove in the outer surface to receive the paste, and a blanket roll for removing the paste from the gravure roll and then applying it onto the substrate. .

The paste 12 is applied on the to-be-printed object 14 in the same form as the pattern of the grooves formed in the gravure roll. The paste 12 may be easily applied in a stripe form, a mesh form, or various other forms. In addition, the paste 12 may include a conductive material depending on the use of the printed pattern. That is, when the printed pattern is used as the shield member of the electrode of the display device or the filter for shielding electromagnetic waves, the paste 12 contains a conductive material.

For example, when the printed pattern is used as a shielding member of the electromagnetic wave shielding filter, the paste 12 may include a conductive metal, a solvent, a binder, an organic material having elasticity, and the like. Silver, copper, nickel, or these alloys can be used as a conductive metal. As the solvent, one of a high boiling point material having a boiling point of 200 ° C. or higher and a low boiling point having a boiling point of 200 ° C. or lower may be selectively used, or a mixture of a high boiling point material and a low boiling point material may be used. As a binder, glass frit may be used. As an organic substance, an acrylic resin, an acrylate resin, polyester, a polyurethane, an oligomer, etc. can be used. In the subsequent firing process the organics are removed and the glass frit is sintered.

The paste 12 coated on the to-be-printed object 14 in the first step S100 has a first width w1. The first width w1 may be smaller than the width of the groove formed in the gravure roll. For example, when the groove of the gravure roll has a width of 30 μm and a depth of 20 μm, the paste 12 applied on the substrate 14 has a width smaller than 30 μm and has a width of at least 20 μm. Can be.

3 is a schematic cross-sectional view illustrating a temporary pattern of the second step S200 illustrated in FIG. 1. Referring to FIG. 3, one of drying, exposure, and thermal curing may be used to cure the paste 12 in the second step S200.

In the case of drying, the paste 12 may be naturally dried at room temperature, or a drying apparatus such as a heat dryer or an infrared dryer may be used. In the latter case, the temperature of the dryer may be 30 ° C to 150 ° C. The higher the drying temperature, the longer the drying time, and the larger the supply / exhaust flow rate, the more effectively the paste 12 can be cured. In the case of exposure, the exposure conditions can be variously set according to the composition of the paste 12. For example, the light amount of the exposure lamp may be 10mJ to 100mJ, and the larger the light amount, the longer the exposure time, and the greater the number of exposures, the more effectively the paste 12 may be cured.

In the case of thermal curing, the thermal curing conditions can also be set in various ways according to the composition of the paste 12. For example, the temperature of the heat curing machine may be at room temperature (approximately 25 ° C.) to 60 ° C., and the higher the curing temperature, the longer the advancing time, and the greater the supply / exhaust flow rate, the more effectively the paste 12 may be cured.

The paste 12 may include an ultraviolet curable organic material. In this case, the applied paste 12 is irradiated with ultraviolet rays to cure the paste 12. On the other hand, the paste 12 may comprise a thermosetting organic material. In this case, heat is applied to the applied paste 12 to cure the paste 12.

In the second step S200, the paste 12 is completely cured to form the temporary pattern 16, and the temporary pattern 16 maintains a shape substantially similar to the paste 12 of the first step S100. The temporary pattern 16 may be formed in a convex shape toward a direction away from the to-be-printed object 14. The temporary pattern 16 has a second width w2. The second width w2 may be equal to or slightly smaller than the first width w1 (see FIG. 2).

As the temporary pattern 16 is formed by completely curing the paste 12 in the second step S200, deformation of the temporary pattern 16 may be minimized in the third step S300 that follows. If it is assumed that the paste is not cured or partially cured, defects in the temporary pattern may occur, such as part of the temporary pattern is removed in the following third step, or the width of the temporary pattern is uneven.

4 is a schematic cross-sectional view illustrating a temporary pattern of the third step S300 illustrated in FIG. 1. Referring to FIG. 4, in the third step S300, a developer may be used to cut the surface of the temporary pattern 16.

The developer is a solution having selective etching characteristics for the temporary pattern 16 and is evenly sprayed onto the substrate 14 through a nozzle (not shown). Since the developer reacts chemically with the temporary pattern 16, the surface of the temporary pattern 16 that contacts the developer is shaved by the chemical reaction with the developer. Thus, after development, the temporary pattern 161 has a smaller width than before development.

The temporary pattern 161 that has passed through the third step S300 has a third width w3 and the third width w3 has a smaller value than the second width w2 (see FIG. 3). The third width w3 can be easily adjusted by controlling the composition of the developer, the method of applying the developer, and the developer application time. The developing solution may include NaOH, and a spray method using a nozzle may be applied. Injection pressure may be 2Kgf to 5Kgf, and the swing angle of the nozzle may be within 60 °. Since the developer used in the third step S300 is removed through a cleaning process, the developer is not left on the to-be-printed object 14.

FIG. 5 is a schematic cross-sectional view illustrating a printing pattern of the fourth step S400 illustrated in FIG. 1. Referring to FIG. 5, the printing pattern 18 is completed through firing in a fourth step S400.

The firing temperature may be approximately 350 ° C to 600 ° C. In the firing process, the organic matter contained in the paste is removed, and the glass frit is sintered to enhance adhesion to the substrate 14. In order to apply a baking process, it is preferable that the to-be-printed object 14 is a glass substrate.

The printed pattern 18 that has passed through the fourth step S400 has a fourth width w4, and the fourth width w4 is larger than the third width w3 of the temporary pattern 161 after development (see FIG. 4). It has a small value. When the second width w2 of the temporary pattern 16 (see FIG. 3) before the development is compared with the fourth width w4 of the completed printed pattern 18, the second width w2 is assumed to be 1. The ratio of the fourth width w4 to the second width w2 may be 0.05 to 0.95. That is, the fourth width w4 of the printed pattern 18 may be reduced from 95% of the minimum second width w2 to 5% of the maximum second width w2.

It is also possible to form the print pattern 18 such that the ratio of the fourth width w4 to the second width w2 is less than 0.05, but in this case, the functionality of the print pattern 18 may be degraded. For example, when the printed pattern 18 is used as an electrode of the display device, the resistance of the electrode may increase, and when used as a shielding member of the electromagnetic shielding filter, the electromagnetic shielding performance of the shielding member may be deteriorated. It is also possible to form the print pattern 18 such that the ratio of the fourth width w4 to the second width w2 exceeds 0.95, but in this case, the width reduction ratio of the print pattern 18 is extremely small, so that the printing The effect of miniaturizing the pattern is insignificant.

By changing the conditions of the above-mentioned curing process and developing process, the width reduction ratio of the printed pattern 18 can be easily controlled. For example, when the paste 12 is applied in a width of approximately 20 μm in the first step S100, the width w4 of the print pattern 18 that has passed through the fourth step S400 is reduced to a maximum of 1 μm. You can.

In the present embodiment, a printing pattern 18 having a width of several μm to 100 μm can be easily formed by using an offset printing process and a developing process having relatively low process costs. That is, in this embodiment, compared to the pattern formation method, which is complicated in process and high in process cost, such as photolithography, the process can be simplified and the process cost can be reduced.

The following table shows the width change of the temporary pattern and the printing pattern according to the process conditions.

From the results of the above table, it can be seen that the width of the printing pattern can be variously changed by controlling the spraying pressure and the spraying speed in the developing step for the same paste that has undergone the same exposure and drying process.

The printed pattern 18 completed by the above-described method includes a display device, for example, an electrode of a plasma display panel, a shielding member of an electromagnetic wave shielding filter attached to the display device, a spacer of a liquid crystal display device, and an RFID; Frequency IDentification) tag can be applied to various fields.

Although the present invention has been described above, it will be readily understood by those skilled in the art that various modifications and variations are possible without departing from the spirit and scope of the claims set out below.

1 is a process flowchart showing a printing pattern forming method according to an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view showing the paste of the first step shown in FIG.

3 is a schematic cross-sectional view showing the temporary pattern of the second step shown in FIG.

4 is a schematic cross-sectional view showing the temporary pattern of the third step shown in FIG.

FIG. 5 is a schematic cross-sectional view showing the print pattern of the fourth step shown in FIG.

Claims (8)

Applying a paste in a specific pattern on the substrate, Curing the applied paste to form a temporary pattern, Cutting the surface of the temporary pattern to reduce the width of the temporary pattern, and Firing the temporary pattern to form a printed pattern Print pattern forming method comprising a. The method of claim 1, In the step of applying the paste, the paste is printed pattern forming method is applied by offset printing. The method of claim 2, The paste includes a conductive material and a glass frit. The method of claim 1, In the step of forming the temporary pattern, the paste is cured by any one of the method of exposure, drying, and thermal curing. The method of claim 4, wherein And the temporary pattern is formed in a convex shape toward a direction away from the to-be-printed object. The method of claim 1, In the step of reducing the width of the temporary pattern, the temporary pattern is a surface shaping pattern by the chemical reaction with the developer. The method of claim 6, And assuming that the width of the temporary pattern measured before the step of reducing the width of the temporary pattern is 1, the width ratio of the print pattern to the width of the temporary pattern is 0.05 to 0.95. The method of claim 1, The method according to any one of claims 1 to 7, And the print pattern is used as one of an electrode of a display device, a mesh-type shielding member of an electromagnetic wave shielding filter, a spacer of a liquid crystal display device, and a radio frequency identification (RFID) tag.

Images