Slot Die Step Measurement Device and Method

Abstract

The present specification relates to an apparatus and method for measuring the step between the lip and shim of a slot die.

Description

Technical Field

[0001] This application claims the benefit of the filing date of Korean Patent Application No. 10-2021-0147971, filed with the Korean Intellectual Property Office on November 1, 2021, and all of its content is incorporated herein by reference.

[0002] This specification relates to an apparatus and method for measuring the step between a lip and a shim of a slot die.

Background Art

[0003] In recent years, due to the depletion of fossil fuels, the price of energy sources has increased, and there has been growing concern about environmental pollution. As a result, demands for alternative energy sources that are environmentally friendly are increasing. Therefore, research on various power generation technologies such as nuclear power, solar power, wind power, and tidal power has been continuously conducted, and there is also high interest in power storage devices for more efficiently using the energy produced in this way.

[0004] In particular, as the technology development and demand for mobile devices increase, the demand for batteries as an energy source has been rapidly increasing. Many studies on batteries that can meet such demands have been conducted.

[0005] Typically, in terms of the shape of the battery, there is high demand for prismatic secondary batteries and pouch-type secondary batteries that are thin and can be applied to products such as mobile phones. In terms of materials, there is high demand for lithium secondary batteries such as lithium-ion batteries and lithium-ion polymer batteries, which have advantages such as high energy density, discharge voltage, and output stability.

[0006] Generally, a secondary battery has a structure including an electrode assembly in which a positive electrode, a negative electrode, and a separator positioned between the positive electrode and the negative electrode are laminated. The positive electrode and the negative electrode are manufactured by coating an electrode slurry containing an active material on a current collector.

[0007] To ensure uniform secondary battery characteristics, the slurry must be coated on the current collector with a uniform thickness. For this purpose, a slurry coating device such as a die coater is used. The slurry coating device includes a slot die that applies the slurry in a relatively thin layer over a large area.

[0008] Such a coating method using a slot die is superior to other coating methods in terms of maintenance and productivity, and has been widely used not only to coat a slurry on a current collector of an electrode of a secondary battery but also in the manufacture of panels for flat panel display devices.

[0009] The slot die applies the slurry to the current collector while moving the slot die itself or the current collector, by discharging the slurry from the ink ejection tip of the slot die in the same way that ink comes out of the nib of a fountain pen.

[0010] At both ends of the slot die in the width direction of the current collector, there is a step between the lip and the shim (shim offset or gap), and when coating using the slot die, ink bleeding occurs in the gap caused by the step due to surface tension.

[0011] In this case, if the difference in height between the lip and the shim is within a certain level, the bleeding will occur uniformly and there will be little variation in the width of the applied slurry. However, as shown in Figure 1, if the difference in height between the lip and the shim is not within a certain level, the variation in the width of the applied slurry will increase.

[0012] Therefore, the difference in level between the lip and the shim must be controlled so as not to deviate from a certain level, and for this purpose, a method must be devised for measuring the difference in level between the lip and the shim. Summary of the Invention [Problem to be solved by the invention]

[0013] This specification provides an apparatus and method for measuring the step between the lip and the shim of a slot die.

Means for Solving the Problems

[0014] One embodiment of this specification measures the step between the lip and the shim of a slot die including two or more bodies provided with a lip at one end and a shim provided to discharge ink between the two or more lips, and includes a laser sensor facing the lip and the shim of the slot die; and a jig that contacts at least a part of the body where the ink-discharging portion of the slot die is located, and provides a step measurement device for the slot die.

[0015] Another embodiment of this specification provides a method for measuring the step of a slot die including two or more bodies provided with a lip at one end and a shim provided to discharge ink between the two or more lips, the method including the step of contacting a jig of a step measurement device provided with a laser sensor at least a part of the upper end of the body where the ink-discharging portion of the slot die is located; and the step of measuring the step between the lip and the shim of the slot die through the laser sensor.

Advantages of the Invention

[0016] The step measurement device for the slot die according to one embodiment of this specification can measure the step between the lip and the shim.

[0017] By judging the step between the lip and the shim measured through the step measurement device for the slot die according to another embodiment of this specification, proper level of step management is possible.

[0018] The step measurement device for the slot die according to another embodiment of this specification is highly portable and can measure the step between the lip and the shim after the ink coating progresses, and can check the change in the step due to the progress of the process at any time.

[0019] The step measurement device for a slot die according to another embodiment of this specification checks the change in the step due to the progress of the ink coating process, and can adjust the step between the lip and the shim when the change in the step is significant.

Brief Description of the Drawings

[0020] [Figure 1] It shows the problem of non-uniformity of the coating interface surface that occurs when the step between the lip and the shim of the slot die becomes large. [Diagram 2] It is an exploded perspective view of a step measurement device according to an embodiment. [Figure 3] It is an assembled perspective view of a step measurement device according to an embodiment. [Figure 4] It is an assembled cross-sectional view of a step measurement device according to another embodiment. [Figure 5] It is a perspective view of a step measurement device according to another embodiment in contact with a slot die. [Figure 6] [Figure 6(a)] Plan view of a step measurement device according to another embodiment of this specification, [Figure 6(b)] Front view of a step measurement device according to another embodiment of this specification, [Figure 6(c)] Side view of a step measurement device according to another embodiment of this specification. [Figure 7] It is a cross-sectional view of an ink ejection tip in a single die. [Figure 8] [Figure 8(a)] Side view of a step measurement device for a slot die according to an embodiment of this specification in contact with a single die, [Figure 8(b)] Side view of a step measurement device for a slot die according to another embodiment of this specification in contact with a single die. [Figure 9] It is a cross-sectional view of an ink ejection tip in a double die. [Figure 10] [Figure 10(a)] Side view of a step measurement device for a slot die according to an embodiment of this specification in contact with a double die, [Figure 10(b)] Side view of a step measurement device for a slot die according to another embodiment of this specification in contact with a double die. [Figure 11][Fig. 11(a)] Cross-sectional view of the experimental slot die fabricated in the example, [Fig. 11(b)] Image of the slot die showing the laser of the step measurement device being sensed.

[0021] <Description of Signs> 100: Step measurement device 110: Body 120: Laser sensor 123: Sensing part 130: Fixture 131: Through hole 133: Contact part 140: Gripping part 200: Single die 211: First body 213: First lip 221: Second body 223: Second lip 230: Shim 300: Double die 311: First body 313: First lip 321: Second body 323: Second lip 331: Third body 333: Third lip 340: First shim 350: Second shim

Mode for Carrying Out the Invention

[0022] Hereinafter, the present invention will be described in detail with reference to the drawings. However, the drawings are for illustrative purposes only, and the scope of the present invention is not limited by the drawings.

[0023] Fig. 2 is an exploded perspective view of a step measurement device according to an embodiment, and Fig. 3 is an assembled perspective view of a step measurement device according to an embodiment.

[0024] Fig. 4 is an assembled cross-sectional view of a step measurement device according to another embodiment, Fig. 6(a) is a plan view of a step measurement device according to another embodiment, Fig. 6(b) is a front view of a step measurement device according to another embodiment, and Fig. 6(c) is a side view of a step measurement device according to another embodiment.

[0025] The step measurement device 100 for a slot die includes a laser sensor 120 and a jig 130. At this time, the laser sensor 120 and the jig 130 are provided separately from each other, and may further include a main body 110 that houses the laser sensor 120 and the jig 130. The laser sensor 120 and the jig 130 are coupled and fixed to the main body 110, and the coupling method is not particularly limited, but they can be fitted. The main body 110 is not particularly limited as long as it can fix the laser sensor 120 and the jig 130, and may be two or more plates, and the cross section may be "

Number

[0026] FIG. 5 is a perspective view of the contact between the step measurement device and the slot die according to another embodiment.

[0027] The laser sensor 120 is provided to face the lip on the ink ejection chip side of the slot die to be measured and the end of the shim. Specifically, it includes two or more bodies 211, 221 provided with lips 213, 223 at one end, and a shim 230 provided so that ink is ejected between the two or more lips, and is provided to face the lip of the slot die and the end of the shim.

[0028] The laser sensor 120 irradiates the lip and the end of the shim of the slot die with a laser, and can sense the laser reflected from the surfaces of the lip and the shim of the slot die to derive the form of the end.

[0029] The laser sensor 120 may include an irradiation unit (not shown) that irradiates the lip and the end of the shim of the slot die with a laser, and a sensing unit 123 that senses the laser reflected from the surfaces of the lip and the shim of the slot die.

[0030] The irradiation unit (not shown) of the laser sensor 120 is provided so that the laser emitted from the light source can reach the measurement target. At this time, since the laser is light with strong straightness, the measurement target is located on the extension line in the irradiation direction.

[0031] The laser irradiated from the laser sensor 120 is not particularly limited as long as it does not affect the material and form of the ink ejection chip of the slot die and is likely to be reflected from the irradiated surface. For example, the above laser can be irradiated with a visible light laser of 380 nm to 800 nm, specifically, it may be a blue laser, more specifically, a 405 nm laser.

[0032] The sensing unit 123 of the laser sensor 120 may be a plate-shaped sensor provided so as to be able to sense the laser reflected from the lip and the surface of the shim of the slot die. Considering the irradiation angle of the laser and the form of the lip and the shim, the angle at which the plate-shaped sensor of the sensing unit 123 is provided can be adjusted and determined so that the reflected laser can reach.

[0033] The laser sensor 120 may include an output unit (not shown) that illustrates the form of the lip and the shim on the ink ejection chip side of the slot die through the information sensed by the sensing unit 123. The form illustrated by the output unit is a longitudinal vertical cross section of the end of the ink ejection chip. For example, it is derived in a form similar to FIGS. 7 and 9, and based on such a form, the difference in height, that is, the step, between the specified points through the coordinates of the step measurement points can be derived.

[0034] The jig 130 is provided so as to be in contact with at least a part of the body where the part where the ink of the slot die is ejected is located. The jig 130 supports the distance between the measurement position, the laser sensor 120, and the measurement target so that the laser sensor 120 can measure the step between the lip and the shim in contact with at least a part of the body.

[0035] The distance between the lip and the laser sensor may be 17 mm or more and 23 mm or less, or 17.8 mm or more and 22.2 mm or less, i.e., 20±2.2 mm. Sensing is performed while maintaining a constant distance between the measurement sensor and the object, and sensing is impossible when the distance deviates from the constant distance.

[0036] The contact area of the jig 130 with the body is not particularly limited as long as the step measurement device 100 can be stably positioned, but the larger the contact area, the higher the stability. Therefore, it is preferable to design the contact area to be as large as possible, taking into account the overall size of the step measurement device.

[0037] As shown in FIG. 8(a) and FIG. 10(a), the jig 130 is

number

[0038] As shown in FIG. 8(b) and FIG. 10(b), the jig 130 is

number

[0039] According to FIGS. 7 and 9 above, the surface of the body where the part where the ink is ejected is located is an inclined surface formed with an inclination at a certain angle with the side surface of the lip when looking at the surface indicated by the arrow showing the part where the jig contacts in FIGS. 7 and 9. Therefore, in order to increase the contact area with the jig, it is preferable that the contact portion 133 of the jig also has the same or a similar inclination angle in consideration of the inclination angle of the inclined surface.

[0040] Since the jig 130 is a part that contacts the body and the lip of the slot die, it is selected to be a material that does not scratch the body and the lip of the slot die that it contacts. For example, the jig can include, but is not limited to, acetal.

[0041] In the step measurement device 100, since the jig 130 contacts the body of the slot die, it is arranged closer to the slot die than the laser sensor 120. Therefore, at least one through hole 131 is provided in the jig 130 so that the laser irradiated from the laser sensor 120 can reach the ink ejection chip of the slot die and the reflected laser can reach the sensing part.

[0042] The through hole 131 is one hole, and the laser can reach the ink ejection chip of the slot die and the reflected laser can reach the sensing part.

[0043] The through hole 131 can include a first hole for the laser to reach the ink ejection chip of the slot die and a second hole for the reflected laser to reach the sensing part.

[0044] The step measurement device of the slot die according to an embodiment of this specification further includes a determination part (not shown).

[0045] The determination unit compares the step between the lip and the shim measured by the laser sensor with a reference value. If the step between the lip and the shim measured by the laser sensor exceeds the reference value, the determination unit determines to reassemble the slot die. The reference value is an important factor in determining the coating amount, coating pattern, etc., and the determination unit checks whether the designed step is maintained. If the step exceeds an allowable value, the determination unit reassembles the slot die to maintain the step within the reference value.

[0046] The reference value may be 300 μm. When the step between the lip and the shim is 300 μm or less, the ink bleeding due to the step is constant, and the width of the applied slurry is maintained at a constant level of variation.

[0047] FIG. 7 is a cross-sectional view of an ink ejection chip in a single die.

[0048] The slot die may be a single die 200, and the slot die being a single die 200 includes a first body 211 having a first lip 213, a second body 221 having a second lip 223, and a shim 230 provided between the first body 211 and the second body 221.

[0049] The laser sensor 120 can measure a step between an end of the first lip 213 and an end of the shim 230. The determination unit can compare the step between the end of the first lip 213 and the end of the shim 230 measured by the laser sensor with a reference value. In this case, the reference value may be a step that is targeted when assembling the single die 200, and may be, for example, 300 μm.

[0050] In addition, the laser sensor 120 can further measure the step between the end of the first lip 213 and the end of the second lip 223.

[0051] FIG. 8(a) is a side view of the step measurement device of the slot die according to one embodiment of the present specification in contact with the single die, and FIG. 8(b) is a side view of the step measurement device of the slot die according to another embodiment of the present specification in contact with the single die. As shown in FIGS. 8(a) and 8(b), the form of contact with the single die can be changed according to the form of the jig 130.

[0052] FIG. 9 is a cross-sectional view of the ink ejection chip in the double die.

[0053] The slot die may be a double die 300. The slot die that is the double die 300 includes a first body 311 provided with a first lip 313, a second body 321 provided with a second lip 323, a third body 331 provided with a third lip 333, a first shim 340 provided between the first lip 313 and the second lip 323, and a second shim 350 provided between the second lip 323 and the third lip 333.

[0054] The laser sensor 120 can measure the step between the end of the first lip 313 and the end of the first shim 340 and the step between the end of the second lip 323 and the end of the second shim 350. The determination unit can compare at least one of the step between the end of the first lip 313 and the end of the first shim 340 and the step between the end of the second lip 323 and the end of the second shim 350 measured by the laser sensor with each reference value. At this time, the reference value may be the target step at the time of assembling the double die 300. For example, the reference value for the step between the end of the first lip 313 and the end of the first shim 340 may be 300 μm.

[0055] In addition, the laser sensor 120 can further measure the step between the end of the first lip 313 and the end of the second lip 323 and the step between the end of the second lip 323 and the end of the third lip 333.

[0056] 10(a) is a side view of a slot die step measurement device according to one embodiment of the present specification contacting a double die, and FIG. 10(b) is a side view of a slot die step measurement device according to another embodiment of the present specification contacting a double die. As shown in FIG. 10(a) and FIG. 10(b), the contact form with the single die can vary depending on the form of the jig 130.

[0057] The slot die step measurement device 100 according to one embodiment of the present specification may further include a gripping portion 140 .

[0058] The step measurement device 100 is a portable device that can be carried by the person performing the measurement and is easy to move and store. Once a slot die is installed in a coating device by stacking each body and shim, it is difficult to remove the installation and then reinstall it. Therefore, it is advantageous for a device for measuring the step of the slot die to be highly portable.

[0059] The gripping portion can be designed to be easily carried by the measurer and to be held by the measurer's hand while the jig is in contact with the slot die during step measurement.

[0060] The step measurement device 100 may further include a control unit (not shown) that controls the laser sensor 120. Each component within the step measurement device 100 is connected to each other by electrical wires for power supply, control, and data output as needed. In addition, the step measurement device 100 is easy to disassemble and connect / install for portability, and each component can be stored in a travel case after disassembly.

[0061] Another embodiment of the present specification provides a method for measuring a step of a slot die including two or more bodies each having a lip at one end and a shim between the two or more lips so that ink can be ejected, the method comprising the steps of: contacting a jig of a step measurement device equipped with a laser sensor with at least a portion of the upper end of the body where the ink ejection portion of the slot die is located; and measuring the step between the lip of the slot die and the shim through the laser sensor.

[0062] In this case, in order to avoid redundant explanation, the step measuring method for the slot die can refer to the explanation of the step measuring device.

[0063] The method for measuring a step of a slot die may further include a step of comparing the step between the lip and the shim measured by the laser sensor with a reference value.

[0064] The method for measuring a step height of a slot die may further include reassembling the slot die if the step height between the lip and the shim measured by the laser sensor exceeds the reference value, where the reference value may be 300 μm. [Example]

[0065] The present invention will be described in more detail with reference to the following examples, which are intended to illustrate the present invention and are not intended to limit the present invention.

[0066] [Example] An experimental slot die with the specifications shown in Figure 11(a) was fabricated, and the offset step was measured using a step measurement device. Measurements were performed 10 times under each of the conditions set in Table 1 below, and an evaluation of the error in the measurement data was planned. In this case, "measurement repeatability with readjustment of the measuring instrument" refers to the reproducibility of data when the measuring instrument is removed from the slot die after measurement and the measurement position is readjusted, and "sensor continuous measurement repeatability" refers to the repeatability of measurement data when measurements are made continuously without removing the measuring instrument from the slot die after measurement.

[0067] The master (certification) test pieces were Mitutoyo master certification test pieces with arbitrarily set step levels, and the aim was to confirm the accuracy of the data values measured by the step measurement device of this specification. Master (certification) test pieces with step levels of 50 μm, 100 μm, and 300 μm were used, and the step levels were selected to be levels that had to be adjusted to the step level between the die lip and shim.

[0068] [Table 1]

[0069] At this time, the step measuring device used a laser under the following conditions.

[0070] - Reference distance (Z axis): 20±2.2mm (repeat level 0.3μm) - Measurement range (X axis): 7.5 mm (repeatability 0.3 μm) - Data interval: 2.5μm - Light source: Blue LED (blue semiconductor laser) - Wavelength: 405nm visible light - Output: 10mV

[0071] When the measurement position of the measuring device, that is, the step measuring device, was repeatedly readjusted according to the scheme in Table 1, the step of the experimental die was measured each time, and the results are shown in Table 2 below.

[0072]

Table 2

[0073] Based on Fig. 11(a), the bottom shim offset is the step between circle 1 and circle 2, the bottom die offset is the step between circle 1 and circle 3, the Top shim offset is the step between circle 3 and circle 4, and the Top die offset is the step between circle 3 and circle 5. At this time, circle 1 to circle 5 respectively mean the positions corresponding to the points shown in red as the step measurement points in Fig. 11(a).

[0074] The image of the slot die shown by sensing the laser of the step measurement device is as shown in Fig. 11(b). By specifying the step measurement points with such an image, the respective offset values were derived.

[0075] According to the plan in Table 1, when repeatedly readjusting the measuring instrument, that is, the step measurement device, and the measurement position of the certification test piece, the results of measuring the thickness of the certification test piece each time are shown in Table 3 below.

[0076]

Table 3

[0077] According to the plan in Table 1, the results of fixing the measuring instrument and continuously sensing the steps of the experimental die are shown in Table 4 below.

[0078]

Table 4

[0079] According to the plan in Table 1, the results of measuring the steps of the experimental die are summarized in Table 5, and the results of measuring the target thickness and the actual measured thickness of the certification test piece are summarized in Table 6.

[0080]

Table 5

[0081]

Table 6

[0082] Through Tables 2 to 6, it can be confirmed that the step measurement device according to the present specification can measure the step (offset) between the lip of the slot die and the shim, and that the reproducibility and reliability of the measured numerical values are high.

Claims

1. A laser sensor that measures a step between the lip and the shim of a slot die including two or more bodies each having a lip at one end and a shim provided so that ink is ejected between the two or more lips; and A jig that contacts at least a part of the body where the ink ejection part of the slot die is located to maintain the distance between the lip and the shim and the laser sensor, a step measuring device for the slot die.

2. The step measuring device for a slot die according to claim 1, further comprising a determination unit that compares the step between the lip and the shim measured by the laser sensor with a reference value.

3. The step measuring device for a slot die according to claim 2, wherein the determination unit determines to reassemble the slot die if the step between the lip and the shim measured by the laser sensor exceeds the reference value.

4. The step measuring device for a slot die according to claim 2, wherein the reference value is 300 μm.

5. The slot die includes a first body having a first lip, a second body having a second lip, and a first shim provided between the first body and the second body, The step measuring device for a slot die according to claim 1, wherein the laser sensor measures a step between an end of the first lip and an end of the shim.

6. The step measuring device for a slot die according to claim 5, wherein the laser sensor measures a step between an end of the first lip and an end of the second lip.

7. The slot die includes a first body having a first lip, a second body having a second lip, a third body having a third lip, a first shim provided between the first body and the second body, and a second shim provided between the second body and the third body, The step measuring device for a slot die according to claim 1, wherein the laser sensor measures a step between an end of the first lip and an end of the first shim and a step between an end of the second lip and an end of the second shim.

8. The laser sensor according to claim 7 measures the step between the end of the first lip and the end of the second lip and the step between the end of the second lip and the end of the third lip. The step measuring device for a slot die.

9. The distance between the lip and the laser sensor is 17 mm or more and 23 mm or less. The step measuring device for a slot die according to claim 1.

10. The step measuring device for a slot die according to claim 1 is a portable device.

11. In a method for measuring the step of a slot die, including two or more bodies each having a lip at one end and a shim provided so that ink is discharged between the two or more lips, Contacting a jig of a step measuring device equipped with a laser sensor to at least a part of the upper end of the body where the ink discharging part of the slot die is located, so as to maintain the distance between the lip, the shim and the laser sensor; and A method for measuring the step of a slot die, including the step of measuring the step between the lip and the shim of the slot die through the laser sensor.

12. The method for measuring the step of a slot die according to claim 11 further includes the step of comparing the step between the lip and the shim measured by the laser sensor with a reference value.

13. The method for measuring the step of a slot die according to claim 12 further includes the step of determining the reassembly of the slot die when the step between the lip and the shim measured by the laser sensor exceeds the reference value.

14. The reference value is 300 μm. The method for measuring the step of a slot die according to claim 12.

Images