Slot die coater

Abstract

A slot die coater according to the present invention may comprise: a plurality of slot die modules which are spaced apart from each other and each include a slot die for applying a coating liquid onto a base material, a first driving unit for moving the slot die in a first axis direction, and a rotating unit for rotating the slot die about a second axis direction; and a module driving unit that moves each of the slot die modules in a third axis direction perpendicular to the first axis direction.

Description

slot die coater

[0001] The present invention relates to a slot die coater having a plurality of slot die modules that are divided and individually driven. This application claims priority to Korean Patent Application No. 10-2024-0050212, filed April 15, 2024, the entire contents of which are incorporated herein by reference.

[0002] With the technological development and increasing demand for mobile devices, the demand for secondary batteries as an energy source is rapidly increasing. These secondary batteries essentially include an electrode assembly, which is a power generation element. The electrode assembly has a structure in which a positive electrode, a separator, and an anode are laminated at least once. The positive and negative electrodes are manufactured by coating and drying a positive active material slurry and a negative active material slurry onto a current collector made of aluminum foil and copper foil, respectively. To ensure uniform charge / discharge characteristics of the secondary battery, the positive active material slurry and the negative active material slurry must be evenly coated onto the current collector, and a slot die coater has been used conventionally.

[0003] Figure 1 illustrates an example of a coating method using a conventional slot die coater.

[0004] Referring to Fig. 1, in the electrode manufacturing method using a slot die coater, an active material slurry discharged from a slot die (30) is applied onto a current collector (12) transported by a coating roll (10). The active material slurry discharged from the slot die (30) is widely applied to one surface of the current collector (12) to form an active material layer. The slot die (30) includes two die blocks (31, 32), and a slot (35) is formed between the two die blocks (31, 32), and the active material slurry can be discharged through a discharge port (37) communicated with one slot (35) to form an active material layer. The slot die coater has the advantage of high-speed coating compared to bar coating or comma coating, and is therefore widely applied from the viewpoint of high productivity.

[0005] Meanwhile, in order to improve production efficiency, a slot die coater having multiple discharge ports on one slot die is being used. Fig. 2 is a schematic perspective view of a conventional slot die coater. Referring to Fig. 2, a slot die (30) is formed with multiple discharge ports (37). The slot die coater can form an active material layer pattern by discharging an active material slurry onto a current collector (12 in Fig. 1). At this time, since the active material slurry is discharged from multiple discharge ports (37), multiple active material layer patterns can be formed at once.

[0006] Meanwhile, the shape of the pattern formed on the current collector, for example, the width or thickness of the pattern, can be controlled by the coating gap, which is the distance between the discharge port (37) and the current collector (12). However, in the conventional slot die coater, a plurality of discharge ports (37) are formed in one slot die. Therefore, the distance between each discharge port (37) and the current collector (12) cannot be individually controlled, and thus, if a defect occurs in any one of the plurality of patterns, there is a problem in that only this pattern defect cannot be immediately corrected.

[0007] The present invention has been created in consideration of the above-described problems, and provides a slot die coater having an improved structure capable of simultaneously forming a plurality of patterns on a substrate and individually controlling the shape of each pattern.

[0008] However, the problems to be solved by the present invention are not limited to the problems described above, and other problems not mentioned can be clearly understood by those skilled in the art from the description of the invention described below.

[0009] The slot die coater of the present invention for solving the above problem may include a slot die for applying a coating liquid on a substrate, a first driving unit for moving the slot die in a first axis direction, and a rotation unit for rotating the slot die with a second axis direction as a rotation axis direction, and may include a plurality of slot die modules arranged to be spaced apart from each other; and a module driving unit for moving each of the slot die modules in a third axis direction orthogonal to the first axis direction.

[0010] According to the present invention, the plurality of slot die modules are arranged on the same straight line along the third axis direction, and each slot die module is individually movable in the third axis direction.

[0011] In addition, according to the present invention, the module driving unit is characterized by including a stator arranged in the third axis direction, and a plurality of movers that are coupled to the slot die module and move along the third axis direction by an electromagnetic force formed between the stator and the slot die module.

[0012] In addition, according to the present invention, the first driving unit has a driving part that moves along the first axis direction, and the driving parts are provided in pairs, and the pair of driving parts are characterized in that they are each connected to the slot die at two connecting points spaced apart from each other.

[0013] In addition, according to the present invention, the first driving unit includes a ball screw, and the nut of the ball screw is connected to the slot die at the joining point.

[0014] In addition, according to the present invention, when a difference in the movement distance of the pair of driving parts occurs, the slot die is configured to tilt in response to the difference.

[0015] In addition, according to the present invention, the two joining points are characterized in that an elastic part that is compressed or relaxed when the slot die is tilted is provided.

[0016] In addition, according to the present invention, the elastic member is characterized in that it is formed in a ring shape.

[0017] In addition, according to the present invention, the slot die is coupled to the rotating part, the driving part of the first driving part is coupled to the rotating part, and when a difference in the movement distance of the pair of driving parts occurs, the rotating part and the slot die coupled to the rotating part are tilted together in response to the difference.

[0018] In addition, according to the present invention, a coupling projection is provided on the driving part, a fastening part to which the coupling projection is coupled is provided on the rotating part, and an elastic part that is compressed or relaxed when the rotating part is tilted is provided between the coupling projection and the fastening part.

[0019] In addition, according to the present invention, the elastic member is characterized in that it is formed in a ring shape and arranged to surround the coupling protrusion.

[0020] In addition, according to the present invention, each slot die module is characterized in that it further includes a second driving unit that moves the slot die in the second axis direction.

[0021] In addition, according to the present invention, the slot die is characterized in that it is configured to be tiltable with the first axis direction as the rotation axis direction.

[0022] In addition, according to the present invention, each slot die module is characterized in that the second driving unit is connected to the slot die to linearly move the slot die in the second axis direction, the rotating unit is connected to the second driving unit to rotate the second driving unit and the slot die together, and the first driving unit is connected to the rotating unit to linearly move the rotating unit, the second driving unit, and the slot die together in the first axis direction.

[0023] In addition, according to the present invention, the second driving part has a driving part that moves along the second axis direction, and the driving parts are provided in pairs, and the pair of driving parts are respectively coupled to the slot die at two coupling points spaced apart from each other, and when a difference in the movement distance of the pair of driving parts occurs, the slot die is tilted in response to the difference.

[0024] In addition, according to the present invention, it is characterized by further including a measuring unit for measuring the shape of a pattern formed by the coating liquid applied on the substrate; and a control unit for controlling the movement of the slot die according to the pattern shape measured by the measuring unit.

[0025] In addition, according to the present invention, the control unit is characterized in that, when the thickness of the pattern is formed to be inclined, the slot die is rotated or tilted with the second axis direction as the rotation axis direction.

[0026] In addition, according to the present invention, the control unit is characterized in that, when the thickness of the pattern is thinner and the width is wider than a reference value, the slot die is tilted around the first axis direction.

[0027] According to the present invention, the movements of multiple slot dies that form patterns on a substrate can be individually controlled. Therefore, if a defect occurs in a specific pattern during pattern formation, the pattern defect can be resolved by controlling the movements of the slot dies that form the pattern. In particular, since this process eliminates the need to shut down the device, the productivity of the device can be improved.

[0028] Furthermore, the present invention enhances the degree of freedom of the slot die. In other words, the slot die can move in various ways. Therefore, by varying the position (or arrangement) of the slot die depending on the type of pattern defect, pattern defects can be efficiently corrected.

[0029] In particular, according to the present invention, the coating gap can be controlled for each slot die. Generally, the thickness of the active material layer is affected by the coating gap. Since the thickness of the active material layer can have a serious impact on the coating quality even if it changes by just a few micrometers, it must be controlled very strictly. According to the present invention, when forming multiple patterns simultaneously on a substrate, the coating gap of each slot die corresponding to each pattern can be individually controlled, thereby exhibiting uniform dimensional precision.

[0030] In addition, various additional effects can be achieved through various embodiments of the present invention. These various effects of the present invention will be described in detail in each embodiment, or descriptions of effects easily understandable to those skilled in the art will be omitted.

[0031] The following drawings attached to this specification illustrate preferred embodiments of the present invention, and together with the detailed description of the invention described below, serve to further understand the technical idea of ​​the present invention, and therefore, the present invention should not be interpreted as being limited to matters described in such drawings.

[0032] Figure 1 is a schematic diagram showing an example of use of a slot die coater according to the prior art.

[0033] Figure 2 is a schematic perspective view of a slot die coater according to the prior art.

[0034] Figure 3 is a schematic perspective view of a slot die coater according to one embodiment of the present invention.

[0035] Fig. 4 is an exploded perspective view of a portion of the slot die coater illustrated in Fig. 3.

[0036] Figure 5 is an exploded perspective view of the slot die module illustrated in Figure 3.

[0037] Figure 6 is a cutaway perspective view of the slot die illustrated in Figure 3.

[0038] Figure 7 is a cutaway perspective view of a slot die according to another embodiment of the present invention.

[0039] Figure 8 is a schematic diagram of a module driving unit according to one embodiment of the present invention.

[0040] Fig. 9 is a schematic diagram for explaining the coupling structure of the first driving unit in a slot die coater according to another embodiment of the present invention.

[0041] Fig. 10 is a schematic cross-sectional view in the VV' direction of Fig. 9.

[0042] Figures 11 to 14 are drawings for explaining the process of correcting a pattern defect.

[0043] FIG. 15 is a schematic perspective view of a slot die module according to another embodiment of the present invention.

[0044] Figure 16 is an exploded perspective view of the slot die module illustrated in Figure 15.

[0045] Figure 17 is a drawing explaining a process of forming a pattern using the slot die coater of the present invention.

[0046] Fig. 18 is a drawing explaining a process of changing a pattern shape using a slot die coater of the present invention.

[0047] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, it should be noted that the terms and words used in this specification and claims should not be interpreted as limited to their typical or dictionary meanings, and should be interpreted with meanings and concepts that conform to the technical spirit of the present invention based on the principle that the inventor can appropriately define the concept of the term to best explain his or her own invention. Therefore, the embodiments described in this specification and the configurations illustrated in the drawings are only some of the most preferred embodiments of the present invention and do not represent all of the technical spirit of the present invention. Therefore, it should be understood that various equivalents and modified examples may exist as of the time of this application.

[0048]

[0049] The slot die coater of the present invention is a device for coating a coating liquid on a substrate. The 'substrate' described below may be a current collector, and the coating liquid may be an 'active material slurry'. The slot die coater of the present invention may be a device for coating one or two types of coating liquids. At this time, the two types of coating liquids may refer to active material slurries that are the same or different from each other in composition (type of active material, conductive material, and binder), content (amount of active material, conductive material, and binder), and physical properties. The slot die coater of the present invention may be applied to the manufacture of electrodes by simultaneously applying one or two types of coating liquids, or by alternately applying two types of active material slurries and performing pattern coating. However, the scope of the present invention is not necessarily limited thereto.

[0050] For example, the substrate may be a porous support constituting a membrane, and the first and second coating solutions may be organic materials with different compositions and properties. In other words, if a thin film coating is required, the substrate, first and second coating solutions may be any materials.

[0051]

[0052] Fig. 3 is a schematic perspective view of a slot die coater according to one embodiment of the present invention. Fig. 4 is an exploded perspective view of a portion of the slot die coater illustrated in Fig. 3. Fig. 5 is an exploded perspective view of the slot die module illustrated in Fig. 3. Fig. 6 is a cut-away perspective view of the slot die illustrated in Fig. 3. Fig. 7 is a cut-away perspective view of a slot die according to another embodiment of the present invention. Fig. 8 is a schematic configuration diagram for explaining a module driving unit according to one embodiment of the present invention.

[0053] Referring to FIGS. 3 to 8, the slot die coater (1000) according to the present embodiment may include a slot die module (500) and a module driving unit (600).

[0054]

[0055] A plurality of slot die modules (500) may be provided. For example, as illustrated in FIG. 3, two slot die modules (500) may be provided. However, in FIG. 3, two slot die modules (500) are illustrated for simplicity and clarity of explanation, and it is obvious that the number of slot die modules (500) may be changed in consideration of the width of the substrate (20), productivity, etc. For example, three, four, nine, or ten slot die modules (500) may be provided, and an even greater number of slot die modules may be provided. In addition, a plurality of slot die modules (500) may be individually operable.

[0056] In order to use a wide current collector as a substrate (20) to increase production, the width of a single slot die (100) may be increased, but in that case, it is difficult to achieve uniformity of the coating gap in the width direction. In the present invention, in order to precisely control the coating gap so that uniform application can be achieved in the width direction, the use of multiple slot dies (100) is proposed, and in particular, a precise individual control configuration of each slot die (100) is proposed.

[0057]

[0058] Specifically, each slot die module (500) may include a slot die (100), a first driving unit (200), and a rotating unit (300).

[0059] The slot die (100) is for supplying a coating liquid, for example, an active material slurry, from an external source and applying the same on a substrate (20). Specifically, as illustrated in FIG. 6, the slot die (100) may include a plurality of die blocks (110, 120), for example, two die blocks. A slot is formed between the die blocks (110, 120), and this slot may serve as a passage through which the coating liquid is discharged, i.e., a discharge portion. In addition, at least one die block (120) among the die blocks (110, 120) may be provided with an injection hole (150) through which the coating liquid is supplied from an external source. The slot die configured in this manner can apply one type of coating liquid on a substrate.

[0060] Meanwhile, the slot die may be configured to apply two types of coating solutions. Specifically, as illustrated in FIG. 7, the slot die (100A) may include three or more die blocks (110, 120, 130). For example, when three die blocks (110, 120, 130) are included, a first slot may be formed between the upper die block (110) and the middle die block (130), and a second slot may be formed between the middle die block (130) and the lower die block (120). In addition, injection holes (150) may be formed in each of the middle die block (130) and the lower die block (120). The slot die configured in this manner may apply two types of coating solutions onto the substrate (20).

[0061] Meanwhile, the structure of the slot die is not limited to the structure described above, and may be configured to apply three or more types of coating solutions. In addition, it may include various structures applicable to the slot die at the time of filing of the present application.

[0062]

[0063] The first driving unit (200) is for moving the slot die (100) in the first axis direction, and more specifically, may be for moving the slot die (100) in a straight line in the first axis direction. Here, the first axis direction may mean the Y-axis direction with reference to FIG. 4. Hereinafter, the first axis direction may be referred to as the front-back direction on a horizontal plane (XY-axis plane). The first driving unit (200) may be connected to the slot die (100). Here, the connection may mean a state in which the first driving unit (200) is directly connected to the slot die (100) or the first driving unit (200) is connected to another configuration that is connected to the slot die (100), so that the driving force of the first driving unit (200) can be transmitted to the slot die (100). In other words, it can mean a combination in which the driving force of the first driving unit (200), that is, the driving force in the Y-axis direction, is transmitted to the slot die (100), thereby enabling the slot die (100) to move linearly in the Y-axis direction. For example, the first driving unit (200) can be coupled to a rotating unit (300) described below, and the slot die (100) can be coupled to the rotating unit (300). In this case, the first driving unit (200) can be connected to the slot die (100) through the rotating unit (300).

[0064] The first driving unit (200) may include a linear actuator (210') that moves the object (i.e., the slot die) in a linear manner. For example, the linear actuator (210') may be implemented in the form of a linear motor, a ball screw, a hydraulic or pneumatic actuator, etc. However, it may be more preferable to utilize a linear motor or a ball screw, etc., which enable precise control of the movement displacement. In addition, the first driving unit (200) may include a first support plate (220). In addition, the linear actuator (210') described above may be coupled to the upper side of the first support plate (220).

[0065]

[0066] The rotating unit (300) may be configured to rotate the slot die (100) with the second axis direction as the rotation axis direction. Here, the second axis direction may refer to the Z-axis direction with reference to FIG. 4. Hereinafter, the second axis direction may be referred to as an up-and-down direction perpendicular to the horizontal plane (XY plane). The rotating unit (300) may be connected to the slot die (100). The meaning of the connection may be similar to that described in the first driving unit (200). The rotating unit (300) may rotate the slot die (100) with the up-and-down direction as the rotation axis direction.

[0067] Specifically, the rotating part (300) may include a rotating plate (320) connected to a motor and a drive shaft of the motor. A slot die (100) may be coupled to the rotating plate (320). For example, the slot die (100) may be coupled and fixed to the upper side of the rotating plate (320). In addition, the rotating part (300) may include a second support plate (310). The second support plate (310) may be arranged on the lower side of the motor to support the motor. In describing the rotating part described above, the motor itself may be a known structure. In addition, the arrangement method of the motor or the structure for connecting the motor to the rotating plate may be changed depending on the relationship with the surrounding structures. Therefore, in this specification, the specific structure of the rotating part (300, and other driving parts are also the same) is omitted and expressed schematically.

[0068]

[0069] The module driving unit (600) may be configured to move the slot die module (500). More specifically, the module driving unit (600) may be configured to move the slot die module (500) linearly in a third-axis direction. Herein, the third-axis direction is a direction orthogonal to the first axis on a horizontal plane, and may refer to the X-axis direction with reference to FIG. 4. Hereinafter, the third-axis direction may be referred to as a left-right direction. The module driving unit (600) is connected to a plurality of slot die modules (500) and may move the slot die modules (500) linearly in a left-right direction. For example, the module driving unit (600) may be coupled to the lower side of each slot die module (500) to support each slot die module (500). The module driving unit (600) may move each slot die module (500) linearly in a left-right direction.

[0070] The above module driving unit (600) may include various configurations that move the object in a straight line, such as a linear motor or a ball screw.

[0071]

[0072] In summary, in the above-described slot die coater (1000), a plurality of slot die modules (500) are provided and can be coupled to the upper side of the module driving unit (600). Each slot die module (500) can be linearly moved left and right (X-axis direction) by the module driving unit (600). In addition, each slot die module (500) can be linearly moved and rotated individually. Specifically, the slot die (100) provided in each slot die module (500) can be linearly moved in the front-back direction (Y-axis direction) by the first driving unit (200). In addition, the slot die (100) can be rotated in the up-and-down direction (Z-axis direction) as the rotation axis direction by the rotation unit (300).

[0073] According to the present embodiment, each slot die (100) can move linearly and rotate. In particular, referring to FIG. 3, each slot die (100) can individually move forward and backward and rotate up and down along the rotation axis. At this time, when the slot die (100) moves forward and backward or rotates, the gap between the slot die (100) and the substrate (20) can be adjusted. Accordingly, if a defect occurs in any one of the plurality of patterns formed on the substrate (20), the pattern defect can be corrected by moving or rotating the slot die (100) forming the corresponding pattern. That is, when forming a plurality of patterns on the substrate (20) with the slot die coater (1000), if a defect occurs in any one of the patterns, the pattern defect can be corrected by controlling the position (posture) of the individual slot die (100) without stopping the entire device. Therefore, the productivity of the slot die coater can be improved.

[0074] In addition, for one substrate (20), two or more slot dies (100) can be applied in the width direction. Each slot die (100) can form one or more patterns. Each slot die (100) can be precisely controlled. For example, each slot die (100) can move linearly and rotate. In addition, it may be possible to control the flow rate of the coating liquid supplied to each slot die (100) differently. Accordingly, the left / right coating gap, width direction position, slurry supply flow rate, etc. can be controlled for each slot die (100), thereby improving the coating quality, for example, coating thickness, coating width, mismatch, etc.

[0075] Meanwhile, a specific example of controlling the slot die to correct the above pattern defect will be described later.

[0076]

[0077] According to the present embodiment, a plurality of slot die modules (500) can be arranged on the same straight line along the third axis direction. In addition, each slot die module (500) can be individually moved in the third axis direction.

[0078] Specifically, a plurality of slot die modules (500) can be arranged on the same straight line along the third axis direction, i.e., the left-right direction. In this regard, when applying an active material slurry to a substrate (20), for example, a current collector, the active material slurry can be applied simultaneously to a plurality of points of a current collector having a wide width, and a portion where a pattern is formed by the active material slurry can be cut and used as a current collector (slitting). At this time, if the interval between the patterns, that is, the interval between the slot dies (100), is wide, the amount of the current collector that is discarded increases, and thus the plurality of slot dies (100) can be arranged at a narrow interval. In particular, since a plurality of patterns are formed on one current collector, the interval between each slot die (100) and the current collector (20) can be initially set to the same interval, and thus, each slot die module (500) can be arranged on the same straight line along the left-right direction.

[0079] In addition, the module driving unit (600) can individually move each slot die module (500) in the left-right direction. For example, as illustrated in FIG. 4, the module driving unit (600) can include a plurality of moving parts (612') that can move linearly in the left-right direction (X-axis direction). Each moving part (612') can individually move in the left-right direction. In addition, one slot die module (500) can be connected to each moving part (612'). More specifically, a moving plate (620) can be coupled to each moving part (612'), and a slot die module (500) can be coupled on the moving plate (620). According to this configuration, each slot die module (500) can independently move in the left-right direction.

[0080] According to the embodiment of the above configuration, the left-right direction (X-axis direction) position of each slot die (100) can be individually controlled. Therefore, when the pattern shape is poor or the gap between patterns needs to be adjusted, the position (position in the X-axis direction) of each slot die (100) can be individually adjusted.

[0081]

[0082] In particular, according to the present embodiment, the module driving unit (600) may include a stator (611) and a mover (612). Specifically, the module driving unit (600) may include a linear motor (610). The linear motor (610) may be configured to include a stator (611) and a mover (612). The stator (611) includes a magnet (or coil) and may be formed to be long in one direction, that is, in a linear movement direction. In particular, in the case of the present embodiment, the stator (611) may be arranged to be long in the left-right direction (X-axis direction). The mover (612) is coupled to the stator (611) and may be linearly moved along the longitudinal direction of the stator (611) by an electromagnetic force with the stator (611). That is, the mover (612) of the linear motor (610) may be the moving part (612') of the module driving unit (600) described above.

[0083] In particular, in the present embodiment, the module driving unit (600) can individually move a plurality of slot die modules (500) in a linear manner, and thus, the module driving unit (600) can include a plurality of movers (612) that move individually. A module driving unit (600) of this type can be configured in two forms.

[0084] First, as illustrated in (A) of FIG. 8, the module driving unit may include a linear motor (610) including one stator (611) and a plurality of movers (612). The stator (611) may be formed and arranged to be elongated in the left-right direction. The plurality of movers (612) may be coupled to the stator (611) so as to be spaced apart from each other. The current supplied to each mover (612) is individually controlled, and thus each mover (612) can independently move in the left-right direction. In this way, a linear motor (610) in which a plurality of movers (612) are provided on one stator (611) may be referred to as a multi-mover linear motor or a multi-slide linear motor.

[0085] The linear motor (610) above can precisely drive multiple movers (612) with a single stator (611), and may have an advantage in space efficiency in particular. However, multiple movers (612) must be controlled simultaneously, and there may be a need to consider interference between movers (612), which is a phenomenon in which electromagnetic force changes according to a change in the position of adjacent movers (612). However, the distance by which the actual slot die (100) must move to correct a pattern defect may be a very small distance. For example, the movement distance of the slot die (100) to correct an actual pattern defect may be in the unit of micrometers. Therefore, the interference between the movers (612) may not be large, and thus it may be sufficiently possible to implement the module drive unit in the form of a multi-mover linear motor.

[0086] Second, as illustrated in (B) of FIG. 8, the module driving unit may include a plurality of linear motors (610A). For example, the module driving unit may include three linear motors (610A), which may in turn include three stators (611) and three movers (612). The three stators (611) may be arranged to be connected in a row in the left-right direction. The three movers (612) may be coupled to each stator (611), one by one. The three linear motors (610A) are each individually controlled, and accordingly, the slot die module coupled to each mover (612) can move individually.

[0087] Meanwhile, referring to FIG. 4, the linear motor (610) may be placed on the upper side of the base part (640). Specifically, the stator (611) may be coupled to the upper side of the base part (640). In addition, linear guides (630) may be installed on both sides of the stator (611). Each linear guide (630) may be formed to be long in the longitudinal direction of the stator (611), that is, in the left-right direction. A pair of linear guides (630) may be installed on both sides of the stator (611). When the mover (612) moves, the mover (612) is supported by the linear guide (630) and can stably move in the left-right direction along the linear guide (630). More specifically, a moving plate (620) may be coupled to the upper side of the mover (612). Both ends of the moving plate (620) can be supported by linear guides (630), and in this state, the moving plate (620) can be moved left and right together with the mover (612). Meanwhile, the above-described base portion (640), moving plate (620), and linear guide (630) can be included as a component of the module driving portion (600).

[0088]

[0089] Again, referring to FIG. 5, the first driving unit (200) described above may include a pair of linear actuators (210'). Each linear actuator (210') may have a driving part (212'). The driving part (212') may refer to a part of the linear actuator (210') that moves in a straight line. The driving part (212') may be called by different names depending on the type of the linear actuator (210'). For example, in a linear motor, the mover may be the driving part (212'). And, in a ball screw, the nut may be the driving part (212').

[0090] The above pair of linear actuators (210') can be connected to the slot die (100). In particular, the driving part (212') is connected to the slot die (100), and the slot die (100) can move linearly in conjunction with the linear movement of the driving part (212'). For example, the driving part (212') can be connected to the lower surface of the rotating part (300), more specifically, the second support plate (310), and the slot die (100) can be connected to the rotating part (300). Then, the driving part (212') can be connected to the slot die (100) through the rotating part (300).

[0091] The above driving parts (212') are provided in pairs, and the pair of driving parts (212') can be connected to the slot die (100) at positions spaced apart from each other. For example, the pair of driving parts (212') can be connected to the lower surface of the second support plate (310), but can be connected at positions spaced apart from each other. At this time, the portion where the driving parts (212') and the second support plate (310) are connected can be referred to as a connecting point. In addition, these connecting points can be spaced apart from each other, and in particular, can be spaced apart in the left-right direction, that is, in the X-axis direction.

[0092] According to the embodiment of the above configuration, the first driving part (200) is connected to the slot die (100) at two connection points instead of one, and the slot die (100) can be moved in the forward and backward direction through the two driving parts (212'). Therefore, the slot die (100) can be stably moved in a straight line.

[0093]

[0094] In particular, the first driving unit (200) may include a ball screw (210). In other words, the linear actuator (210') included in the first driving unit (200) may be a ball screw (210). The ball screw (210) may include a screw shaft (211), a nut (212), and a ball bearing. The screw shaft (211) may have threads formed along the longitudinal direction. The screw shaft (211) may be connected to a servo motor and rotate. The nut (212) is coupled to the screw shaft (211) and may move linearly along the longitudinal direction of the screw shaft (211) in conjunction with the rotation of the screw shaft (211). The ball bearing may be arranged between the screw shaft (211) and the nut (212). For reference, the drawings in this specification schematically illustrate the configuration of a ball screw (210), and thus may differ from the actual shape of the ball screw. However, since the ball screw is a well-known configuration, even if it is simplified in the drawings, those in the relevant industry will be able to sufficiently understand it, and further detailed descriptions of the ball screw may be omitted.

[0095] In the present embodiment, the nut (212) of the ball screw (210) may correspond to the aforementioned driving part (212'). The nut (212) is connected to the slot die (100), and the slot die (100) may move according to the linear movement of the nut (212).

[0096] In particular, the ball screw (210) can precisely control its movement distance. Furthermore, the ball screw (210) is not large in size and can be relatively simple in structure. Therefore, utilizing the ball screw (210) allows for a compact and efficient implementation of the first drive unit (200).

[0097]

[0098] Meanwhile, the slot die can be tilted at a predetermined angle depending on the driving method of the first driving unit. This will be described below with reference to FIGS. 9 and 10.

[0099] Fig. 9 is a schematic diagram illustrating the coupling structure of the first driving unit in a slot die coater according to another embodiment of the present invention. Fig. 10 is a schematic cross-sectional view in the VV' direction of Fig. 9.

[0100] Referring to Fig. 9, the nut (212) of the ball screw (210) can be coupled to the rotating part (300), more specifically, the second support plate (310). For example, the nut (212) may be provided with a coupling protrusion (213). The coupling protrusion (213) may be formed integrally with the nut (212), or alternatively, may be mechanically coupled to the nut (212) through a separate coupling means, for example, a coupling means such as a screw or a pin. A fastening part (311) may be provided on the lower surface of the second support plate (310). In addition, the fastening part (311) may be provided with a coupling groove that is concavely formed upward. The coupling protrusion (213) of the nut (212) is inserted into the coupling groove of the fastening part (311), and thus the nut (212) and the fastening part (311) can be coupled to each other. At this time, although not shown in the drawing, the joining projection (213) and the fastening part (311) can be joined using additional joining means such as screws or pins.

[0101] As described above, the nuts (212) are provided in pairs and can be coupled to the second support plate (310) at two coupling points. At this time, the two coupling points can be spaced apart from each other in the left-right direction (X-axis direction). In other words, as illustrated in FIG. 10, the nuts (212), more precisely, the coupling protrusions (213) provided on the nuts (212) and the fastening parts (311) of the second support plate (310) can be coupled. In this coupled state, as illustrated in FIG. 10 (A), when the two nuts (212) move forward or backward by the same distance, the second support plate (310) (and the slot die coupled thereto) can move forward or backward by the same distance.

[0102] Meanwhile, among the two nuts (212), only one nut (212) can be moved while the other nut (212) is stationary. For example, as illustrated in (B) of FIG. 10, the nut (212) positioned on the left is fixed while only the nut (212) on the right can advance. In this case, as illustrated in (B) of FIG. 10, the second support plate (310) can be tilted at a predetermined angle with the Z-axis as the rotation axis direction.

[0103] In this regard, if the coupling projection (213) and the fastening part (311) are completely joined without any tolerance, the two nuts (212) may theoretically not be able to move to different distances. Alternatively, if the nuts (212) are forced to move to different distances with a stronger driving force, the ball screw (210) or a portion of the coupling point may be damaged.

[0104] However, in reality, there may be a predetermined assembly tolerance at the point where the coupling protrusion (213) and the fastening part (311) are coupled (i.e., the coupling point). For example, the space between the coupling protrusion (213) and the fastening part (311) in FIG. 10, i.e., the area indicated by reference numeral 312', may be an assembly tolerance. In addition, because there is this tolerance (312'), when only the right nut (212) is further rotated, the second support plate (310) may tilt with the Z-axis direction as the rotational axis direction, as illustrated in (B) of FIG. 10. At this time, the degree of tilting may correspond to the difference in the movement distance of a pair of nuts (212).

[0105] For reference, in order to help visual understanding, the gap of the tolerance (312') is expressed broadly in FIG. 10, but the actual tolerance may be finer. In this regard, during the process of applying a coating solution to a substrate (20), for example, a current collector, the gap between the slot die (100) and the current collector may be very small, for example, several to several tens of micrometers (μm). Accordingly, the distance or angle by which the slot die (100) is moved or tilted to correct a pattern defect may be much smaller than that. For example, in an actual work process, the difference in the moving distance for tilting may be several μm, and the degree to which the slot die (100) is tilted accordingly may be very small. Therefore, even if the size of the tolerance (312') is very small, the slot die (100) can be tilted by utilizing this tolerance space, and this tilting can be sufficiently utilized to control the slot die (100).

[0106] Meanwhile, the above description is intended to explain the principle or phenomenon that the slot die may tilt due to the tolerance when there is a tolerance between the two components, i.e., the coupling projection (213) and the fastening part (311), and the moving distances of the two nuts (212) are different. For this purpose, a simple and easy-to-understand coupling structure is explained as an example. Therefore, it is self-evident that the structure or form in which the nut (212) and the second support plate (310) are coupled may be changed in various forms during the actual product manufacturing process.

[0107] According to the present embodiment, the slot die (100) can be tilted. Therefore, when a pattern defect occurs, the pattern defect can be efficiently corrected by tilting the slot die (100). In particular, in the case of the present embodiment, a separate component, such as a motor for rotating the slot die (100), may not be provided to tilt the slot die (100). In other words, by utilizing the first driving unit (200), the slot die (100) can be moved linearly in the Y-axis direction and also tilted. Therefore, the slot die coater (1000) can be manufactured compactly and efficiently.

[0108]

[0109] Meanwhile, the slot die coater (1000) may further include an elastic member (312). The elastic member (312) may be for more precisely controlling the tilting of the slot die (100). Specifically, as described above, if there is a difference in the moving distance of the two nuts (212), the slot die (100) may tilt. At this time, the tilting may occur by utilizing the tolerance (312') space at the point where the coupling protrusion (213) and the fastening part (311) are coupled. To put it more directly, the position of the coupling protrusion (213) may be misaligned within the tolerance range (space), and as a result, the slot die (100) may tilt.

[0110] However, when using a tolerance (312') in this way, it may be difficult to precisely control the degree of tilting according to the difference in moving distance. In other words, the degree of tilting corresponding to the difference in moving distance must be functionalized and utilized for slot die control. However, when tilting using a tolerance, there may be limitations in its accuracy (accuracy of the functionalization, repeatability, etc.). This may be because the tolerance itself is set by taking into account a certain error range.

[0111] The elastic member (312) may be intended to solve the above-described problem. Specifically, the elastic member (312) has elasticity and can be compressed and restored. As the elastic member (312) is compressed and restored, it can compensate for the difference in the movement distance of a pair of nuts (212). Specifically, if a difference occurs in the movement distance of the nuts (212), the position of the engaging protrusion (213) may be misaligned as described above. In this case, in the above-described embodiment, the tolerance (312') provided this space, i.e., the space in which the engaging protrusion (213) may be misaligned. On the other hand, in the present embodiment, the elastic member (312) can provide this space by being compressed and restored.

[0112] Again, referring to FIG. 10, for example, the elastic member (312) may be formed in a ring shape. This elastic member (312) may be coupled to the engaging projection (213) by surrounding it. In other words, the engaging projection (213) may be inserted into the elastic member (312). At this time, the engaging projection (213) may be coupled in a forced-fit manner so as to be completely in close contact with the elastic member (312). Then, the elastic member (312) may be placed between the engaging projection (213) and the fastening part (311).

[0113] For reference, in the above-described embodiment, the reference numeral 312' was described as a tolerance space, but in the case of the present embodiment, the reference numeral 312 may mean an elastic portion. That is, the elastic portion (312) may be arranged in the space where the tolerance (312') in the previous embodiment is formed, that is, the space between the coupling protrusion (213) and the fastening part (311). For reference, in this specification, the same parts in the drawings are described as a tolerance and an elastic portion by changing only the reference numerals to more clearly explain the difference in effect in the two embodiments by directly comparing the meanings of the tolerance (312') and the elastic portion (312) in the same structure (position). However, this does not mean that the thickness of the elastic portion (312) is as thin as the tolerance (312'), and the elastic portion (312) may have a predetermined thickness.

[0114] Returning again, in the state where the elastic members (312) are arranged as described above, when a pair of nuts (212) move forward (or backward) equally as shown in (A) of Fig. 10, the second support plate (310) can move forward without tilting to either side. At this time, both elastic members (312) can maintain the same shape, for example, a circular shape.

[0115] Meanwhile, as illustrated in (B) of FIG. 10, when only the right nut (212) advances a certain distance further, the two elastic parts (312) may be compressed respectively. For example, the right elastic part (312) may be compressed at the upper right side, and the left elastic part (312) may be compressed at the lower left side. In addition, when the elastic parts (312) are compressed in this way, the position of the coupling protrusion (213) may be changed, and accordingly, the second support plate (310) may be tilted. At this time, the degree of tilting may be functionalized according to the difference in movement distance by considering the shape (thickness), elastic strength, etc. of the elastic part (312).

[0116] According to the present embodiment, the slot die (100) can be tilted by utilizing the elastic deformation of the elastic member (312). At this time, the elastic deformation of the elastic member (312) can be linear and have high reproducibility or reliability. Therefore, the tilting of the slot die (100) can be controlled more precisely.

[0117]

[0118] Meanwhile, although not shown in the drawing, the slot die coater (1000) according to the present invention may further include a measuring unit and a control unit.

[0119] The measuring unit may be a device that measures the shape of a pattern formed on a substrate (20), for example, the thickness or width of the pattern. For example, the measuring unit can measure the thickness or width of the pattern by irradiating a laser toward the pattern and receiving the laser reflected from the pattern surface. The measuring unit may be installed to be movable in the width direction of the substrate (20), so as to measure the shapes of a plurality of patterns. Alternatively, by providing a plurality of measuring units, the shapes of a plurality of patterns can be measured.

[0120] The control unit can receive the shape of each pattern measured by the measurement unit. If the shape of the pattern is defective, the control unit can correct the pattern shape by controlling the motion of the slot die (100) forming the pattern. To this end, the control unit is electrically connected to the driving unit that controls the motion of each slot die (100), i.e., the first driving unit (200), the rotation unit (300), and the module driving unit (600), and can control the driving thereof.

[0121]

[0122] Hereinafter, an embodiment of controlling the motion of the slot die (100) to correct a defect that occurs in some patterns during the process of forming a pattern using a slot die coater (1000) according to the present invention will be described.

[0123] First, in the slot die coater (1000) according to the present invention, each slot die (100) is capable of linear movement in the Y-axis direction (by the first driving unit) and linear movement in the X-axis direction (by the module driving unit), and is capable of rotation (by the rotating unit) with the Z-axis direction as the rotation axis direction. In addition, tilting with the Z-axis direction as the rotation axis may also be possible.

[0124] Figures 11 to 14 are drawings for explaining the process of correcting a pattern defect.

[0125] As in (A) of Fig. 11, the thickness of the pattern (P2) formed by the right slot die (102) may be thinner than the normal pattern (P1) (P2 <P1). 이 경우, 도 11의 (B)에서와 같이, 우측 슬롯다이(102)를 Y축 방향으로 이동시켜, 슬롯다이(102)와 기재(20) 사이의 간격을 넓힐 수 있다. 즉, 좌측 슬롯다이(101)와 별개로 우측 슬롯다이(102)의 코팅 갭을 변화시킬 수 있다. 그러면, 우측 슬롯다이(102)에 의해 형성되는 패턴(P2)의 두께가 정상적인 두께로 변경될 수 있다(P2=P1). 이와 같이 좌측 슬롯다이(101)와 우측 슬롯다이(102)를 개별 제어하여 패턴(P1)과 패턴(P2)을 적합하게 형성할 수 있다.

[0126]

[0127] As illustrated in (A) of Fig. 12, the pattern (P1) formed by the left slot die (101) can be formed to be inclined. In this case, as illustrated in (B) of Fig. 12, if the left slot die (101) is tilted in the opposite direction to the incline, the shape of the pattern (P1) can be corrected. In other words, left / right coating gap adjustment is possible even within one slot die (101). In this way, the left slot die (101) and the right slot die (102) can be individually controlled to suitably form the pattern (P1) and the pattern (P2).

[0128]

[0129] At this time, the tilting method can rotate the left slot die (101) around the Z-axis through the rotating part (300). Alternatively, the left slot die (101) can be tilted by utilizing the first driving part (200) (i.e., by moving only one of the two nuts).

[0130] Alternatively, the rotation by the rotating part and the tilting by the first driving part can be used in combination. For example, if the shape of the pattern requires the left slot die (101) to be tilted by about 10 degrees, the left slot die (101) can be tilted by about 5 degrees through the first driving part, and the left slot die (101) can be rotated (tilted) by about 5 degrees in the same direction through the rotating part. Then, the left slot die (101) can be tilted by about 10 degrees.

[0131] In particular, when these two methods are used in combination, there may be advantages over using either method alone. Specifically, tilting by the first drive unit fundamentally utilizes the phenomenon of the coupling point being misaligned within a tolerance range, and thus, there may be limitations to the degree of tilting.

[0132] Also, tilting by the first driving unit and rotation (tilting) by the rotating unit may have different tilting patterns of the slot die. To simplify the explanation for easier understanding, tilting by the rotating unit is a method of rotating based on the center of the slot die. For example, when the slot die is rotated counterclockwise, the center position of the slot die is fixed, and when the right end moves forward by 3 degrees, the left end moves backward by 3 degrees. On the other hand, the method of tilting by the first driving unit is a method in which, when the left end is fixed and the right end moves forward by 3 degrees, the slot die rotates around the left end as the rotation center axis, and at this time, the center of the slot die may also move forward by about 1.5 degrees. Of course, in actual tilting, the slot die may tilt in a slightly different way during the process of twisting, but it is clear that the slot die tilts in a different way from when it rotates by the rotating unit. Therefore, by controlling the motion of the slot die by combining tilting by the first driving unit and rotation by the rotating unit, the slot die can be controlled in a more efficient and diverse manner, and as a result, pattern defects can be corrected more efficiently.

[0133]

[0134] As illustrated in (A) of FIG. 13, the width (length in the X-axis direction) of the pattern (P1) formed by the left slot die (101) may be narrower than the reference value, and the width of the pattern (P2) formed by the right slot die (102) may be wider than the reference value. In this case, as illustrated in (B) of FIG. 13, if the left slot die (101) is moved closer to the substrate (20) (i.e., the coating gap is reduced), the width of the pattern (P1) may be widened and adjusted to the reference value. Conversely, if the right slot die (102) is moved to widen the gap with the substrate (20), the width of the pattern (P2) may be narrowed and adjusted to the reference value. In this way, the left slot die (101) and the right slot die (102) may be individually controlled to suitably form the pattern (P1) and the pattern (P2).

[0135]

[0136] When coating on both sides of the substrate (20), a pattern is first formed on one side of the substrate (20) and then on the opposite side. However, as illustrated in (A) of FIG. 14, the patterns (P2) formed on both sides of the substrate (20) in the right slot die (102) may mismatch, i.e., not be aligned. In this case, as illustrated in (B) of FIG. 14, the mismatch phenomenon can be corrected by moving the right slot die (102) in a direction that offsets the mismatch, i.e., to the left. By adjusting the movement of the right slot die (102) in the width direction in this way, the left slot die (101) and the right slot die (102) can be individually controlled to suitably form the pattern (P1) and the pattern (P2).

[0137] As another example, the slot die's individual left / right coating gap and slurry flow rate can be adjusted independently, so that the coating width can be changed while maintaining a flat coating thickness profile.

[0138]

[0139] FIG. 15 is a schematic perspective view of a slot die module according to another embodiment of the present invention, and FIG. 16 is an exploded perspective view of the slot die module illustrated in FIG. 15.

[0140] Referring to FIGS. 15 and 16, the slot die module (500A) according to the present embodiment may further include a second driving unit (400) compared to the slot die module (500) illustrated in FIG. 5 described above. Hereinafter, the second driving unit (400) will be described.

[0141] The slot die module (500A) according to the present embodiment may include a first driving unit (200), a rotating unit (300), a second driving unit (400), and a slot die (100).

[0142] The first driving unit (200) may be positioned at the lowest side. The rotating unit (300) may be coupled to the upper side of the first driving unit (200). The specific configurations and functions of the first driving unit (200) and the rotating unit (300) may be substantially the same as those described above, and thus a detailed description thereof will be omitted.

[0143] The second driving unit (400) is for moving the slot die (100) linearly in the second axis direction, i.e., the up-down direction (Z-axis direction). The second driving unit (400) may be connected to the slot die (100). Specifically, the second driving unit (400) may include a third support plate (410) coupled to the upper side of the rotating unit (300), and a linear actuator (420) coupled to the third support plate (410). At this time, the linear actuator (420) may be arranged so that its driving part can move linearly in the Z-axis direction. For example, the linear actuator (420) may be arranged in a vertically erected form. The linear actuator (420) may be implemented in the form of a ball screw.

[0144] For example, the nut of the ball screw may be coupled to the rear of the slot die (100). When the ball screw moves, the slot die (100) may move up and down. The configuration or coupling method of the ball screw may be similar to or substantially the same as the configuration or coupling method of the ball screw in the first driving unit described above (however, the arrangement direction of the ball screw is different).

[0145] The slot die module (500A) configured in this manner is coupled to a module driving unit, and each slot die module (500A) can individually move in the left and right directions by the module driving unit.

[0146] According to the embodiment of the above configuration, the slot die (100) can be moved in the up and down direction. That is, the movement of the slot die (100) can be controlled in a more diverse manner (the degree of freedom of the slot die (100) is increased), and accordingly, the structure or shape of the pattern formed on the substrate (20) can be controlled (changed) more efficiently.

[0147] Figure 17 is a drawing explaining a process of forming a pattern using the slot die coater of the present invention.

[0148] Referring to FIG. 17, as illustrated in (A) of FIG. 17, when forming a pattern on a substrate (20), for example, a current collector, through a plurality of slot dies (101, 102), two adjacent patterns (P1, P2) may be spaced apart from each other by a certain distance. This may be because the slot dies (101, 102) are arranged to be spaced apart from each other, and also because the discharge portion (T) of the slot dies has a narrower width than the slot dies (101, 102). In this case, since the portion between the patterns (P1) and the patterns (P2) is discarded after cutting, a large amount of current collector may be wasted.

[0149] However, as illustrated in (B) of FIG. 17, if the right slot die (102) is moved upward and then moved to the left by a certain distance and then the pattern (P1, P2) is formed, the gap between the two patterns (P1, P2) can be narrowed. Therefore, the amount of wasted current collector can be reduced, and as a result, productivity can be improved. Furthermore, if the position of the right slot die (102) is well adjusted, the patterns (P1, P2) formed by the two slot dies (101, 102) can be combined to form one pattern, or the two patterns (P1, P2) can be overlapped to a certain extent. That is, various types of patterns can be formed, such as a pattern wider than the width of the discharge portion (T) of the slot die (for example, twice).

[0150]

[0151] Meanwhile, the slot die (100) may be configured to tilt with the Y-axis as the rotation axis direction. Such tilting may be implemented by the second driving unit (400). Hereinafter, this will be described with reference to FIG. 16, FIG. 9, and FIG. 10.

[0152] Referring to Fig. 16, the second driving unit (400) may be equipped with a pair of linear actuators (420). At this time, the linear actuators (420) may be implemented in the form of ball screws. The nuts of each ball screw may be coupled to the rear of the slot die (100), but may be coupled at coupling points spaced apart from each other in the X-axis direction.

[0153] For example, although not shown in the drawing, a coupling projection may be provided on the ball screw constituting the second driving unit, and a fastening part to which the coupling projection is coupled may be provided on the rear of the slot die. In addition, an elastic part may be arranged between the coupling projection and the fastening part. That is, the structure in which the ball screw constituting the second driving unit and the slot die are coupled may be similar to or substantially the same as the coupling structure of the first driving unit and the second support plate described above with reference to FIGS. 9 and 10.

[0154] According to the embodiment of the above configuration, if there is a difference in the movement distance of a pair of nuts coupled to the slot die (100), the slot die (100) can be tilted corresponding to this difference. At this time, the slot die (100) can be tilted in the Y-axis direction toward the rotational axis direction. In addition, if the degree of freedom of the slot die (100) increases in this way, the structure or shape of the pattern formed on the substrate (20) can be controlled (changed) more efficiently.

[0155] In particular, in the case of the present embodiment, rather than adding a separate configuration, for example, a rotating section, to tilt the slot die (100) in the Y-axis direction, a second driving section (400) for moving the slot die (100) in the Y-axis direction can be utilized. Accordingly, the degree of freedom of the slot die (100) can be increased without further complicating the configuration of the device.

[0156]

[0157] Hereinafter, with reference to FIG. 18, an embodiment of controlling a pattern shape in a slot die coater according to the present embodiment will be described. FIG. 18 is a drawing explaining a process of changing a pattern shape using the slot die coater of the present invention.

[0158] In (A) of Fig. 18, the slot die (100) is arranged parallel to the X-axis direction. In this state, when the slot die (100) is tilted with the Y-axis direction as the rotation axis direction as in (B) of Fig. 18, the width of the pattern can be narrowed. For example, if the width of the pattern (P1) shown in (A) of Fig. 18 is W and the angle at which the slot die (100) is tilted is θ, the width of the pattern (P1) shown in (B) of Fig. 18 can theoretically be narrowed to Wcosθ. In addition, when the amount of the coating liquid discharged from the slot die (100) is constant, if the width of the pattern is narrowed in this way, the width of the pattern can become thicker by that amount. Of course, the width or thickness of the pattern may not change in accordance with the geometric theory described above, but it can be clearly seen that the width of the pattern can be changed by this principle.

[0159]

[0160] As described above, in the slot die coater (1000) according to the present invention, when a pattern defect occurs, the control unit can individually control only the corresponding slot die (100) to resolve the pattern defect. Specifically, when there is a defect in the pattern shape measured by the measuring unit, the control unit controls the position and posture of the slot die so that the defect can be resolved. In other words, the coating gap between the slot die and the substrate can be adjusted, thereby correcting the pattern defect.

[0161] In particular, in the case of the present invention, each slot die (100) can individually move linearly in the X-axis, Y-axis, and Z-axis directions. In addition, rotation (rotation by the rotating unit) and tilting (tilting by the first driving unit) with the Z-axis direction (second axis direction) as the rotation axis are possible. Furthermore, tilting (tilting by the second driving unit) with the Y-axis direction as the rotation axis is possible. That is, according to the present invention, there are various options (for example, 6 degrees of freedom) that can control the position and attitude of the slot die, and the control unit can efficiently control the slot die by appropriately utilizing these options.

[0162] For example, as described above in FIG. 12, when the pattern (P1) is formed to be inclined (i.e., the thickness of the pattern is different in the width direction (X-axis direction)), the shape of the pattern (P1) can be corrected by rotating or tilting the slot die (101) in the Z-axis direction. In particular, when the slot die is controlled by combining tilting and rotation, the slot die can be controlled more efficiently. This may be because the rotation and tilting behave in different ways, as described above. Accordingly, the control unit can control the slot die using this method.

[0163] In addition, as described in FIG. 18, if the pattern (P1) is wider (in the X-axis direction) and thinner than the reference value, this can be corrected by tilting the slot die (100) about the Y-axis direction (first axis direction) as the rotation axis. Of course, as in the case of correcting the P2 pattern shape in FIG. 11, a method of increasing the coating gap between the slot die (P2) and the substrate (20) can be used, but tilting the slot die (100) as in FIG. 18 may be a more efficient method. Accordingly, the control unit can control the slot die using this method. For reference, the reference value may mean the width and thickness of a normal pattern (i.e., a pattern set by the user).

[0164]

[0165] Meanwhile, in the above-described embodiment, it was described that one discharge port was formed in each slot die. However, if a core having multiple openings is used, two or more discharge ports may be formed in each slot die.

[0166] For example, each slot die is commonly applied to one substrate. One slot die may be configured to form one or more patterns. Preferably, slot dies are provided in a number corresponding to the number of patterns in order to control each of the multiple patterns formed in the width direction. For example, the number of openings in the core may be one, and two slot dies may be placed side by side in the width direction of the substrate, thereby forming two patterns in the width direction. For another example, the number of openings in the core may be one, and four slot dies may be placed side by side in the width direction of the substrate, thereby forming four patterns in the width direction. For yet another example, the number of openings in the core may be two, and two slot dies may be placed side by side in the width direction of the substrate, thereby forming four patterns in the width direction.

[0167] In addition, although the above-described embodiment describes a plurality of slot die modules being arranged in a row, some of the plurality of slot die modules may be arranged horizontally, and the remaining some may be arranged vertically.

[0168] In addition, in the above-described embodiment, it was described that a plurality of slot dies are arranged to face the same direction. In other words, it was described that a plurality of slot dies dispense a coating solution toward a single substrate. Alternatively, some of the plurality of slot dies may be arranged to face forward and some may be arranged to face backward. This arrangement may be implemented by rotating the slot dies using a rotating unit. In addition, when the slot dies are arranged in this manner, a process may be performed in which some of the slot dies dispense a coating solution to a first substrate disposed in the front, and the remaining slot dies dispense a coating solution to a second substrate disposed in the rear. In other words, a process of forming patterns on different substrates or on different areas on the same substrate may be performed.

[0169]

[0170] Hereinafter, a method for coating an active material slurry using a slot die coater of the present invention will be briefly described with an example. The slot die coater is applied to the manufacture of a positive electrode of a secondary battery. The positive electrode has a structure in which a lower active material layer formed by a lower slurry layer and an upper active material layer formed by an upper slurry layer are sequentially laminated on a current collector. The lower active material layer contains a high content of a conductive material, and the upper active material layer contains a relatively low content of a conductive material. In this case, the conductive material content of the lower active material layer can be controlled within the range of 0.5 to 5 wt%. By reducing the conductive material content of the upper active material layer, the active material content on the electrode surface can be increased and the electrical conductivity can be lowered to a certain level. In particular, when the conductive material content of the upper active material layer is controlled to a very low level of 0.02 wt% or less, the exothermic reaction during a short circuit inside the cell can be reduced.

[0171] In another example, the average particle size (P1) of the active material forming the lower active material layer is in the range of 50 to 95% of the average particle size (P2) of the active material forming the upper active material layer. In this case, an active material having a relatively small particle size is applied to the lower active material layer. By applying an active material having a relatively large particle size to the upper active material layer, electrolyte impregnation can be facilitated and smooth ion and hole movement can be induced.

[0172] Here, the flow rate ratio of the first coating liquid and the second coating liquid may be 1:1. The viscosity of the first coating liquid and the second coating liquid may be 1000 cps or more. Since it is necessary to be able to coat a coating liquid having a viscosity of 1000 cps or more, the slot die coater of the present invention has a different structure from a device that applies a general resin liquid such as a photosensitive emulsion liquid, a magnetic liquid, a liquid that provides anti-reflection or anti-glare properties, a liquid that provides a viewing angle expansion effect, a pigment liquid for a color filter, etc. It is not a device that can be achieved by changing it. The first coating liquid and the second coating liquid may contain graphite, a conductive agent, CMC, and a binder.

[0173] For example, the present invention can be applied to the manufacture of a positive electrode of a secondary battery by coating a positive electrode active material slurry using a slot die coater. The positive electrode includes a current collector and a positive electrode active material layer formed on the surface of the current collector. The current collector may be an electrically conductive material such as Al or Cu, and may be used appropriately according to the polarity of the current collector electrode known in the secondary battery field. The positive electrode active material layer may further include one or more of a plurality of positive electrode active material particles, a conductive material, and a binder. In addition, the positive electrode may further include various additives for the purpose of supplementing or improving electrochemical characteristics.

[0174] The active material is not limited to a specific component as long as it can be used as a positive electrode active material of a lithium ion secondary battery. Non-limiting examples thereof include layered compounds such as lithium manganese oxide (LiMn2O4, LiMnO2, etc.), lithium cobalt oxide (LiCoO2), lithium nickel oxide (LiNiO2), or compounds substituted with one or more transition metals; chemical formula Li 1+x Mn 2-x Lithium manganese oxides such as O4 (where x is 0 to 0.33), LiMnO3, LiMn2O3, LiMnO2; lithium copper oxide (Li2CuO2); vanadium oxides such as LiV3O8, LiV3O4, V2O5, Cu2V2O7; chemical formula LiNi 1-x M x Ni-site type lithium nickel oxide represented by O2 (where M = Co, Mn, Al, Cu, Fe, Mg, B or Ga and x = 0.01 to 0.3); chemical formula LiMn 2-x M x A lithium manganese composite oxide represented by O2 (wherein M = Co, Ni, Fe, Cr, Zn or Ta, and x = 0.01 to 0.1) or Li2Mn3MO8 (wherein M = Fe, Co, Ni, Cu or Zn); LiMn2O4 in which a part of the Li in the chemical formula is replaced with an alkaline earth metal ion; a disulfide compound; and Fe2(MoO4)3 may include one or a mixture of two or more thereof. In the present invention, the positive electrode may include at least one of a polymer-based solid electrolyte, an oxide-based solid electrolyte and a sulfide-based solid electrolyte as a solid electrolyte material.

[0175] The conductive material can be added typically in an amount of 1 wt% to 20 wt% based on the total weight of the mixture including the active material. The conductive material is not particularly limited as long as it has conductivity without causing a chemical change in the battery, and for example, it may include one or a mixture of two or more selected from the following conductive materials: graphite such as natural graphite or artificial graphite; carbon black such as carbon black, acetylene black, Ketjen black, channel black, furnace black, lamp black, and summer black; conductive fibers such as carbon fiber or metal fiber; metal powders such as fluorinated carbon, aluminum, and nickel powder; conductive whiskers such as zinc oxide or potassium titanate; conductive metal oxides such as titanium oxide; and conductive materials such as polyphenylene derivatives.

[0176] The above binder is not particularly limited as long as it is a component that assists in the bonding of the active material and the conductive material and the bonding to the current collector, and examples thereof include polyvinylidene fluoride, polyvinyl alcohol, carboxymethyl cellulose (CMC), starch, hydroxypropyl cellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene, polyethylene, polypropylene, ethylene-propylene-diene monomer (EPDM), sulfonated EPDM, styrene butadiene rubber, fluororubber, and various copolymers. The binder may typically be included in an amount of 1 wt% to 30 wt%, or 1 wt% to 10 wt%, relative to 100 wt% of the electrode layer.

[0177] The present invention can also be applied to the manufacture of a negative electrode of a secondary battery by coating a negative electrode active material slurry using a slot die coater. The negative electrode includes a current collector and a negative electrode active material layer formed on the surface of the current collector. The negative electrode active material layer may further include one or more of a plurality of negative electrode active material particles, a conductive material, and a binder. In addition, the negative electrode may further include various additives for the purpose of supplementing or improving electrochemical characteristics.

[0178] The above negative active material is a carbon material such as graphite, amorphous carbon, diamond-like carbon, fullerene, carbon nanotube, carbon nanohorn, lithium metal material, alloy material such as silicon or tin, Nb2O5, Li5Ti4O 12 , oxide materials such as TiO2, or their composites can be used. For the negative electrode, the conductive material, binder, and current collector, refer to the content described for the positive electrode.

[0179] The active material slurry containing the positive or negative active material has a very high viscosity. For example, the viscosity may be 1000 cps or more. The viscosity of the active material slurry for use in forming a secondary battery electrode may be 2000 cps to 30000 cps. For example, the negative active material slurry may have a viscosity of 2000 cps to 4000 cps. The positive active material slurry may have a viscosity of 8000 cps to 30000 cps. Since it is necessary to be able to coat a coating liquid having a viscosity of 1200 cps or more, the slot die coater of the present invention has a different structure from a device that applies a coating liquid having a lower viscosity than this, such as a photographic photosensitive emulsion, a magnetic liquid, a liquid imparting anti-reflection or anti-glare properties, a liquid imparting a viewing angle expansion effect, a pigment liquid for a color filter, and the like, and it is not a device that can be achieved by changing it. The slot die coater of the present invention is intended for applying an active material slurry that may include, for example, an active material having an average particle size of about 10 ㎛, and therefore differs from the structure of other coating liquids that do not contain particles of such a size, and is not a device that can be achieved by changing it. The slot die coater of the present invention can be used as a coater for electrode manufacturing.

[0180]

[0181] As described above, although the present invention has been described by limited embodiments and drawings, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical idea of ​​the present invention and the equivalent scope of the claims to be described below by a person having ordinary skill in the art to which the present invention pertains.

[0182] Meanwhile, although terms indicating directions such as up, down, left, and right are used in this specification, it is obvious to those skilled in the art that these terms are only for convenience of explanation and may vary depending on the location of the target object or the location of the observer.

[0183]

[0184] [Explanation of symbols]

[0185] 1000: Slot die coater 500: Slot die module

[0186] 100: Slot die 200: First drive unit

[0187] 210: Ball screw 210': Linear actuator

[0188] 212: Nut 212': Drive part

[0189] 213: connecting projection 220: first support plate

[0190] 300: Rotating part 310: Second support plate

[0191] 311: Fastening part 312: Elastic part

[0192] 312': Tolerance 320: Turntable

[0193] 400: Second drive unit 410: Third support plate

[0194] 420: Linear actuator 600: Module drive unit

[0195] 610: Linear motor 611: Stator

[0196] 612: Mover 612': Moving Part

[0197] 620: Moving plate 630: Linear guide

[0198] 640: Bass section

Claims

1. A plurality of slot die modules having a slot die for applying a coating liquid on a substrate, a first driving unit for moving the slot die in a first axis direction, and a rotation unit for rotating the slot die in a second axis direction as a rotation axis direction, and are arranged to be spaced apart from each other; and A slot die coater characterized by including a module driving unit that moves each of the slot die modules in a third axis direction that is orthogonal to the first axis direction.

2. In paragraph 1, A slot die coater, characterized in that the plurality of slot die modules are arranged on the same straight line along the third axis direction, and each slot die module is individually movable in the third axis direction.

3. In paragraph 2, A slot die coater characterized in that the module driving unit includes a stator arranged in the third axis direction and a plurality of movers that are coupled to the slot die module and move along the third axis direction by an electromagnetic force formed between the stator and the slot die module.

4. In paragraph 1, The above first driving part has a driving part that moves along the first axis direction, A slot die coater characterized in that the above driving parts are provided in pairs, and the pair of driving parts are each connected to the slot die at two connecting points spaced apart from each other.

5. In paragraph 4, The above first driving unit includes a ball screw, A slot die coater characterized in that the nut of the ball screw is connected to the slot die at the joining point.

6. In paragraph 4, A slot die coater characterized in that when a difference in the movement distance of the pair of driving parts occurs, the slot die is configured to tilt in response to the difference.

7. In paragraph 6, A slot die coater characterized in that the two connecting points are provided with an elastic member that is compressed or relaxed when the slot die is tilted.

8. In paragraph 7, A slot die coater characterized in that the elastic member is formed in a ring shape.

9. In paragraph 4, The above slot die is coupled to the above rotating part, The driving part of the first driving unit is coupled to the rotating unit, A slot die coater characterized in that when a difference in the movement distance of the above pair of driving parts occurs, the rotating part and the slot die coupled to the rotating part are tilted together in response to the difference.

10. In paragraph 9, The above driving part is provided with a coupling projection, The above rotating part is provided with a fastening part to which the above coupling projection is coupled, A slot die coater characterized in that an elastic part that is compressed or relaxed when the rotating part is tilted is provided between the above-mentioned joining projection and the above-mentioned fastening part.

11. In paragraph 10, A slot die coater characterized in that the elastic member is formed in a ring shape and arranged to surround the coupling projection.

12. In paragraph 1, A slot die coater, characterized in that each of the above slot die modules further includes a second driving unit that moves the slot die in the second axis direction.

13. In paragraph 12, A slot die coater characterized in that the slot die is configured to be tiltable by a second driving unit.

14. In paragraph 13, Each of the above slot die modules, The second driving unit is coupled to the slot die to move the slot die linearly in the second axis direction, The above rotating part is coupled to the second driving part, and rotates the second driving part and the slot die together, A slot die coater characterized in that the first driving unit is coupled to the rotating unit and configured to move the rotating unit, the second driving unit, and the slot die together in a linear direction in the first axis direction.

15. In paragraph 13, The above second driving part has a driving part that moves along the second axis direction, The above driving parts are provided in pairs, and the pair of driving parts are respectively coupled to the slot die at two coupling points spaced apart from each other. A slot die coater characterized in that when a difference occurs in the movement distance of the pair of driving parts, the slot die tilts in response to the difference.

16. In paragraph 13, A measuring unit for measuring the shape of a pattern formed by the coating solution applied on the above substrate; and A slot die coater, characterized in that it further includes a control unit that controls the movement of the slot die according to the pattern shape measured by the measuring unit.

17. In paragraph 16, A slot die coater characterized in that the control unit rotates or tilts the slot die with the second axis direction as the rotation axis direction when the thickness of the pattern is formed to be inclined.

18. In paragraph 16, A slot die coater, characterized in that the control unit tilts the slot die around the first axis direction when the thickness of the pattern is thinner and the width is wider than a reference value.

Images