Method and system for controlled application of primer liquid and resin to a substrate for roll-to-plate nanoimprinting

Abstract

The present invention relates to a method for controlled application of a primer and a resin to a substrate in roll-to-roll nanoimprinting, comprising the steps of: applying at least one primer to at least one substrate by spraying, and subsequently applying at least one resin to the at least one substrate by droplet application, wherein the at least one primer is applied to the at least one substrate in a first predetermined pattern, and the at least one resin is applied to the at least one substrate in a second predetermined pattern, wherein at least a portion of the second predetermined pattern overlaps with the first predetermined pattern.

Description

Technical Field

[0001] This invention relates to a method for controlled application of a primer and resin onto a substrate for roll-to-roll nanoimprinting. The invention also relates to a system for controlled application of a primer and resin onto a substrate for roll-to-roll nanoimprinting. Background Technology

[0002] Primers are typically used to promote adhesion between a substrate (e.g., glass) and a resin layer subsequently applied for (nano)imprinting. Typically, the primer is applied as an ultrathin layer across the entire surface of the substrate, with a thickness constant between 0.1 nanometers and several micrometers. Conventional primer application methods include spin coating and blade coating. However, spin coating is difficult to apply to large (>300 mm) and non-circular substrates commonly used in roll-to-roll nanoimprinting, while blade coating may not produce a sufficiently thin primer layer. Furthermore, both of these coating techniques struggle to achieve localized control over the liquid distribution. Alternatively, spray coating can be a preferred technique. This technique allows the entire surface of the substrate to be imprinted to be covered with a primer, and the primer thickness is designed to maintain a generally constant thickness on the surface. Imprinting resin is then applied to the primer-treated substrate, after which imprinting can be performed. A drawback of these current techniques is that they typically require relatively large amounts of primer and resin to ensure the production of the final product. This results in high costs due to the use of excessive material and limits process controllability. Summary of the Invention

[0003] Therefore, the object of the present invention is to provide an optimized method and system for applying a primer and resin to a substrate for roll-to-roll nanoimprinting, or at least to provide an alternative to known methods and systems.

[0004] Therefore, the present invention provides a method for controlled application of a primer and resin onto a substrate, preferably for nanoimprinting, particularly for roll-to-roll nanoimprinting, comprising the following steps: At least one primer is applied to at least one substrate by spraying, wherein the viscosity of the at least one primer is in the range of 0.001 to 1000 mPa·s, particularly 0.01 to 100 mPa·s, and more particularly 0.1 to 10 mPa·s; subsequently Optionally, at least one resin is applied to the at least one substrate by droplet application, preferably wherein the viscosity of the at least one resin is in the range of 0.1 to 50,000 mPa·s, particularly 1 to 2,000 mPa·s, more particularly 5 to 1,000 mPa·s, and even more particularly 10 to 200 mPa·s. The at least one primer is applied to the at least one substrate in a first predetermined pattern, and the at least one resin is preferably applied to the at least one substrate in a second predetermined pattern, wherein at least a portion of the second predetermined pattern overlaps with the first predetermined pattern.

[0005] The method according to the invention has several advantages over conventional methods for applying a primer and resin to a substrate for roll-to-roll nanoimprinting. By spraying at least one primer into at least one substrate in a first predetermined pattern, and by droplet application into at least one resin into the at least one substrate in a second predetermined pattern, wherein at least a portion of the second predetermined pattern overlaps with the first predetermined pattern, this combination allows both the primer and resin to be applied precisely and efficiently. The method according to the invention allows specific designated areas of the substrate to be imprinted to be coated with a primer and subsequently coated with resin. In this way, by applying these substances in a predetermined pattern, the amount of primer and / or resin applied can be optimized and, in particular, reduced. Conventional methods typically apply excessive amounts of primer, covering the entire substrate, while the method according to the invention only requires supplying primer to predetermined areas. The method according to the invention allows portions of the substrate to remain free of primer. This is desirable, for example, in areas where resin adhesion to the substrate is undesirable, particularly in areas where the substrate should remain bare. This may be the case, for example, at the entrance pupil of the optical waveguide in an augmented reality (AR) device. Another example illustrating the benefits of this approach is applying the primer to a relatively large substrate assembly containing multiple small components that require separate primer supply. This allows for scaling up production, as multiple small products can be contained within a single large substrate. The areas between these components should generally not be supplied with primer, as this could negatively impact the overall product. Yet another example is that, for aesthetic and / or optical reasons, a product may require locally applied higher or lower amounts of primer.

[0006] When applying a primer with a viscosity range of 0.001 to 1000 mPa·s, particularly 0.01 to 100 mPa·s, and even more particularly 0.1 to 10 mPa·s, it is advantageous to apply the at least one primer by spraying. The relatively high viscosity of the primer allows for controlled application of the primer to a predetermined area onto the surface by spraying it in a predetermined pattern. Therefore, spraying is superior to application techniques such as spin coating or blade coating.

[0007] When the resin viscosity ranges from 0.1 to 50,000 mPa·s, particularly 1 to 1,000 mPa·s, and even more particularly 10 to 200 mPa·s, it is advantageous to apply the at least one resin by droplet placement. This viscosity is low enough to achieve droplet formation and its specific and controlled positioning. When referring to droplet placement, it means applying droplets of at least one resin to a substrate. When referring to a predetermined pattern, it may also refer to a predetermined template. In alternative embodiments, it is conceivable that the at least one resin is applied to the at least one substrate by coating techniques, particularly slot die coating, blade coating, spin coating, and / or combinations thereof. It is also conceivable that droplet placement is combined with coating techniques.

[0008] Preferably, at least a portion of the first predetermined pattern is different from at least a portion of the second predetermined pattern. Specifically, the first predetermined pattern and the second predetermined pattern are different patterns. It is conceivable that at least a portion of the first predetermined pattern and at least a portion of the second predetermined pattern are similar or identical to each other. Specifically, the first predetermined pattern and the second predetermined pattern can be similar or identical patterns. The second predetermined pattern and the first predetermined pattern can completely overlap. Specifically, the second predetermined pattern can completely overlap with the first predetermined pattern. This embodiment helps control resin adhesion to desired areas of the substrate, particularly areas where the substrate should remain exposed.

[0009] At least one substrate used in the method according to the invention is specifically a substrate to be imprinted. The at least one substrate is preferably a plate-shaped substrate or a sheet-like substrate, configured and / or suitable for roll-to-roll imprinting. It is conceivable that the at least one substrate to be imprinted comprises a plurality of imprinted sections. Therefore, it is conceivable that at least one primer is applied to each imprinted section. It is conceivable that a first predetermined pattern is substantially identical in construction to the imprinted sections. The method according to the invention also enables the application of primer to multiple substrates subsequently or even substantially simultaneously using the same apparatus or system. For example, it is conceivable to mount multiple substrates on a carrier. This method enables the efficient and controlled application of primer and resin to multiple substrates substantially simultaneously or at least sequentially.

[0010] The method according to the invention may also be referred to as an imprinting method. At least one primer liquid may also be referred to as a primer. In the context of the invention, the primer liquid is configured to increase and / or promote adhesion between the substrate to be imprinted and the resin applied for imprinting.

[0011] At least one primer is specifically applied to a predetermined portion of at least one substrate such that the area defined by the primer is smaller than the total area of ​​the at least one substrate. In this way, a portion of the surface of at least one substrate will not be covered by the primer. For example, the predetermined portion of the substrate covered by the primer may be at least 10% smaller than the total area of ​​the at least one substrate, preferably at least 20% smaller, more preferably at least 30% smaller. Applying the primer only to a predetermined portion of the substrate results in a significantly reduced amount of primer to be applied compared to conventional methods in which the entire surface of the substrate is completely covered by the primer. As mentioned above, for certain applications, it is undesirable to completely cover the substrate with the primer. By applying the primer in a predetermined spray pattern, the use of a stencil can be omitted. The latter still results in the application of excessive primer and is more prone to defects due to alignment difficulties and / or liquid leakage.

[0012] The primer region may be defined by at least one primer liquid applied to at least one substrate. The resin region may be defined by at least one resin applied to at least one substrate. Preferably, the primer region is larger than the resin region. The primer region is larger than the resin region, especially at least before an optional subsequent imprinting step is performed on at least a portion of the resin. This embodiment is advantageous because it provides a sufficient amount of primer liquid on the substrate for coating the primer-treated substrate with resin. This embodiment further helps to optimize the amount of primer liquid and / or resin applied.

[0013] When referring to spraying in the context of this invention, it can also be expressed as the application of a primer via spraying techniques and / or via at least one spraying operation. At least one primer is typically applied via at least one spray valve. Using at least one spray valve can positively influence the controlled application of the primer to the substrate to be imprinted. When referring to a spray valve, it may also mean a spray nozzle, or at least one spray valve may include at least one spray nozzle. At least one primer is preferably applied via multiple spray valves. Using multiple spray valves allows for the efficient and effective delivery of a relatively large amount of primer.

[0014] This method may involve at least a portion of a first predetermined pattern having a non-uniform thickness distribution of a primer. Therefore, at least one primer can be applied such that at least a portion of the first predetermined pattern has a non-uniform thickness distribution of the primer. For example, at least a portion of the first predetermined pattern may have a variable layer thickness. It is conceivable that the at least one substrate is provided with a primer such that a portion of it has a locally higher or lower amount of primer compared to other portions of the substrate. For example, it is conceivable that at least a portion of the at least one primer is applied to the at least one substrate with a variable layer thickness. This can be achieved, for example, by spraying portions of the substrate multiple times with the primer. Therefore, it is conceivable that a portion of the substrate is sprayed with the primer once, while another portion of the substrate is sprayed with the primer at least two or more times. It is also possible that the method and / or system is configured to provide different amounts of primer during its application, particularly to achieve a variable layer thickness of the primer. This can be achieved, for example, by adjusting the amount of primer sprayed by at least one spray valve, preferably each individual spray valve. For example, it may be advantageous to apply an increased primer layer thickness in the area surrounding the area to be imprinted. For example, these areas could be resin outflow areas outside the effective areas. In these areas, it's necessary to ensure that excess resin adheres to the substrate rather than to the imprinting stencil, as adhesion to the stencil could contaminate the system. Therefore, a thicker primer layer may be required in the outflow areas than in the effective areas, where the primer thickness is typically kept to a minimum in the effective areas.

[0015] It is possible that at least a portion of at least one primer is applied to at least one substrate with a substantially non-uniform layer thickness, and / or at least a portion of at least one primer is applied to at least one substrate with a substantially uniform layer thickness. Preferably, at least a portion of at least one primer is applied to at least one substrate with a controlled and / or predetermined thickness. It is possible that at least a portion of at least one primer is applied to at least one substrate such that a layer thickness gradient exists. The uniformity of the applied primer layer is important, particularly the thickness and distribution of the primer, as well as its optical properties such as refractive index, to obtain a consistent and uniform final imprinted product. This is especially important for products that require a relatively thin resin layer (typically 1 µm or less). Therefore, control of the primer layer thickness is relevant.

[0016] At least one primer is applied to the substrate to be imprinted via at least one spray valve, preferably via multiple spray valves. During the application of the at least one primer to the at least one substrate, the spray valve height, displacement speed, orientation, and / or displacement pattern of the at least one spray valve can be controlled and / or adjusted. Preferably, during the application of the at least one primer to the at least one substrate, the spray valve height, displacement speed, orientation, and / or displacement pattern of the at least one spray valve can be controlled and / or adjusted such that the at least one primer is applied to the at least one substrate with a first predetermined pattern and / or a generally non-uniform layer thickness. It is advantageous if the parameters of the at least one spray valve can be controlled and / or adjusted, as this provides greater flexibility in the achievable primer pattern and layer thickness. For example, increasing the displacement speed of the at least one spray valve may result in a decrease in layer thickness. Similarly, increasing the spray valve height of the at least one spray valve, or increasing the distance between the substrate to be imprinted and the at least one valve, may also result in a decrease in layer thickness. Adjusting the displacement pattern of the at least one spray valve can simultaneously affect both the layer thickness and the pattern of the applied primer. Adjusting the orientation of at least one spray valve, preferably multiple spray valves, helps improve the controllability of the spray pattern, especially the first predetermined pattern. It is also conceivable that the orientation of at least some of the spray valves, preferably each spray valve, can be adjusted individually.

[0017] At least a portion of at least one resin is preferably applied via droplet distribution technology. At least a portion of at least one resin is typically applied via at least one jet valve or piezoelectrically actuated valve. Alternatively, at least one inkjet nozzle may be used. In this manner, the resin can be applied in a controlled and precise manner. Possibly, at least a portion of at least one resin is applied to the at least one substrate in an intermittent pattern. For example, at least a portion of at least one resin may be applied in a discontinuous pattern. For example, at least one resin may be applied to the substrate via droplet distribution, thereby obtaining dots or droplets of resin on the substrate. It is also conceivable that the resin may be applied via droplet distribution, thereby forming a resin layer on the substrate.

[0018] At least a portion of the second predetermined pattern preferably overlaps with the first predetermined pattern. In this way, resin can be applied at least to the area where the primer has been applied. For example, it is conceivable that the first predetermined pattern and the second predetermined pattern are substantially identical. Thus, the second predetermined pattern can be defined by a non-uniform and / or dotted layer. The resin is preferably applied such that the imprinting of the resin, particularly roll-to-roll imprinting using a flexible stencil, results in the first predetermined pattern being substantially completely covered by the resin. It is possible that, during application, at least a portion of the resin defining the second predetermined pattern is displaced relative to the first predetermined pattern. It is possible that at least a portion of the resin droplets is applied in a repeating configuration. Thus, at least a portion of the resin droplets or dots may be arranged in lines and / or shapes. It is possible that at least a portion of the droplets, preferably substantially all of the resin droplets, have substantially the same volume. However, it is also conceivable that the applied resin volume may deviate, for example, from the second predetermined pattern.

[0019] In one possible embodiment, the first pattern comprises at least two pattern segments spaced apart from each other. At least one pattern segment may have a different layer thickness and / or shape than the other pattern segment. Alternatively, at least one pattern segment may have a substantially the same layer thickness and / or shape as the other pattern segment. In yet another possible embodiment, the first pattern comprises at least two pattern segments aligned with each other, wherein the at least two segments have different layer thicknesses.

[0020] At least one primer liquid preferably has a viscosity in the range of 0 to 100,000 mPa·s, more preferably in the range of 0 to 100 mPa·s, and most preferably in the range of 0.1 to 10 mPa·s. Possibly, at least one primer liquid has a viscosity in the range of 0.3 to 8 mPa·s, preferably in the range of 0.5 to 5 mPa·s, and more preferably in the range of 1 to 3 mPa·s. However, it is also conceivable that at least one primer liquid has a viscosity in the range of 0.5 to 3 mPa·s. At least one primer liquid may, for example, have a viscosity of less than 10 mPa·s, preferably less than 5 mPa·s, and more preferably less than 2.5 mPa·s.

[0021] At least one resin preferably has a viscosity in the range of 0.1 to 50,000 mPa·s, particularly 1 to 1,000 mPa·s, and even more particularly 10 to 200 mPa·s. However, it is also conceivable that at least one resin has a viscosity in the range of 0.2 to 2,500 mPa·s, or possibly in the range of 10 to 100 mPa·s, or in the range of 5 to 2,000 mPa·s. In one possible embodiment, at least one resin has a viscosity in the range of 15 to 150 mPa·s, preferably in the range of 20 to 100 mPa·s, and more preferably in the range of 25 to 75 mPa·s.

[0022] The method according to the invention may further include a step of (nano)imprinting at least a portion of the resin. Imprinting is preferably nanoimprinting performed by roll-to-plate imprinting using a generally flexible template. Imprinting is configured, for example, to provide an imprinted texture. Typically, the generally flexible template includes textured areas. The texture may, for example, include textures with dimensions typically ranging from 500 micrometers to 25 nanometers. The texture may, for example, include repeating patterns and / or the texture may be configured to optimize the optical properties of the imprinted (cured) resin or the imprinted product. For example, at least a portion of the texture may be applied for optical purposes. The flexible template is particularly configured for nanoimprint lithography transfer processes. It is also conceivable that at least one flexible template is attached to at least one roller and / or at least one flexible template is disposed on at least one roller. For example, the roller may be at least partially covered by at least one flexible template.

[0023] At least a portion of the first predetermined pattern and at least a portion of the second predetermined pattern may be adjacent to each other and / or spaced apart. A transition region may exist on at least a portion of at least one side edge of the first predetermined pattern, wherein the transition region can be defined as a region where the portion of the second predetermined pattern adjacent to a portion of the first predetermined pattern transitions to the overlapping portion of the first and second predetermined patterns. A portion of the first predetermined pattern and a portion of the second predetermined pattern may be arranged to be adjacent to each other and / or spaced apart. Therefore, a portion of the first predetermined pattern and a portion of the second predetermined pattern may not overlap. Specifically, at least a portion of the transition region is formed as a front edge in an optional imprinting step. The front edge may be defined as the starting position of the imprint. During the optional imprinting step, at least a portion of the resin is imprinted from the front edge of the first predetermined pattern along the imprinting direction until its rear edge. The rear edge preferably has no transition region. Optionally, at least before the imprinting step, the rear edge does not have a second predetermined pattern. This embodiment is advantageous because during imprinting, the resin flows along the imprinting direction, particularly from the front edge to the rear edge. Therefore, during imprinting, the resin layer moves and / or spreads on the primer along its imprinting direction. This helps to provide an optimized method for applying resin to a substrate.

[0024] The present invention also relates to a method for controlled application of a primer onto a substrate prior to roll-to-roll nanoimprinting, comprising applying at least one layer of at least one primer onto at least one substrate via at least one spray valve, wherein the viscosity of at least one primer is in the range of 0.001 to 1000 mPa·s, particularly 0.01 to 100 mPa·s, more particularly 0.1 to 10 mPa·s, wherein at least one layer of at least one primer is applied to a first predetermined region of at least one substrate and / or has a predetermined (variable) layer thickness. Any of the described embodiments of primer application are applicable to the above method.

[0025] The present invention also relates to a system for controlled application of a primer and resin to a substrate, particularly for roll-to-roll nanoimprinting, preferably by a method according to any one of the preceding claims, comprising: At least one (displaceable) primer applicator for applying at least one primer to at least one substrate to be imprinted, the primer applicator comprising at least one spray valve configured to spray at least one primer with a viscosity in the range of 0.001 to 1000 mPa·s, particularly 0.01 to 100 mPa·s, more particularly 0.1 to 10 mPa·s; Preferably, at least one (displaceable) resin applicator is used to apply at least one resin, preferably by droplet distribution, to the at least one substrate, the viscosity of which is in the range of 0 to 50,000 mPa·s, particularly 1 to 2,000 mPa·s, more particularly 5 to 1,000 mPa·s, and even more particularly 10 to 200 mPa·s; and At least one control unit is configured to control and / or adjust at least one parameter, and preferably to control and / or adjust at least two parameters of the at least one primer applicator, particularly during the application of primer to the at least one substrate, wherein the parameter is selected from the group consisting of: the spray valve height of at least one spray valve, the primer flow rate from at least one spray valve, the displacement velocity of the at least one primer applicator, the orientation of at least one spray valve and / or at least one spray valve, and the displacement pattern of the at least one primer applicator and / or at least one spray valve.

[0026] The present invention also relates to a system for controlled application of a primer liquid onto a substrate for roll-to-roll nanoimprinting. The system according to the invention enables at least one primer liquid to be applied to at least one substrate in a first predetermined pattern and at a predetermined layer thickness. Furthermore, the method allows at least one resin to be applied to at least one substrate in a second predetermined pattern via droplet placement, particularly such that at least a portion of the second predetermined pattern overlaps with the first predetermined pattern. At least one control unit is preferably configured to control and / or adjust at least one parameter, preferably at least two parameters, more preferably at least three parameters, belonging to at least one primer liquid applicator, substantially simultaneously during the application of the primer liquid to the substrate.

[0027] It is also conceivable that at least one (displaceable) resin applicator is configured to apply at least one resin to at least one substrate by coating, particularly by slit die coating, blade coating, spin coating, and / or combinations thereof. It is also conceivable that droplet placement is combined with coating techniques.

[0028] The at least one control unit is preferably configured to control and / or adjust at least one parameter during the displacement of the at least one primer applicator and / or at least one spray valve. In this way, a first predetermined pattern and / or desired layer thickness can be obtained efficiently and in a controlled manner. The at least one system particularly provides a start / stop configuration in which the application of at least one primer and / or at least one resin to the substrate can be substantially fully controlled. Specific parameters adjustable by the at least one control unit have individual and / or synergistic effects on the pattern and layer thickness of the applied primer. Increasing the spray valve height of the at least one spray valve reduces the layer thickness, while increasing the primer flow rate from the at least one spray valve increases the layer thickness. These two parameters may also further affect the obtained spray pattern. The displacement velocity and displacement pattern of the at least one primer applicator and / or at least one spray valve generally affect the pattern and layer thickness. The system and method according to the invention enable the application of a primer with variable thickness to a substrate.

[0029] In one possible embodiment, at least one primer applicator includes at least one liquid channel for supplying at least one primer to at least one spray valve. The control unit may be configured to control and / or adjust the size of at least one opening in the at least one liquid channel supplying the primer to the spray valve. It is also contemplated that the control unit is configured to control and / or adjust the size of at least one nozzle opening of the at least one spray valve. In practice, a larger liquid channel opening and / or nozzle opening will result in a higher primer flow rate. For example, at least one opening may be controlled by a stroke. The stroke setting determines the size of the opening in the liquid channel supplying the primer to the (nozzle) opening.

[0030] It is also conceivable that at least one control unit is configured to control at least one parameter of at least one spray valve, wherein the at least one parameter is selected from the group consisting of: fan-shaped air pressure (in bar), primer flow rate (in milliliters / second), spray valve stroke setting, liquid pressure (in bar), and / or spray shape. The spray shape is related to the shape of the jet, particularly when it contacts the surface, and therefore to the area to be covered. It is also conceivable that at least one control unit is configured to control and / or adjust the spray volume, spray volume distribution, and / or spray pattern of at least one spray valve. For example, a system, particularly at least one primer applicator, may include at least two spray valves, wherein the spray jet of the first spray valve is larger than that of the second spray valve, and / or wherein the spray shape of the first spray valve differs from that of the second spray valve.

[0031] It is conceivable that a system, particularly at least one primer applicator, includes multiple spray valves. At least two spray valves may be positioned substantially parallel to each other. The system, particularly at least one primer applicator, may also include multiple spray valves arranged in a spatial configuration. Each spray valve is preferably configured to spray at least one primer with a viscosity in the range of 0.001 to 1000 mPa·s, particularly 0.01 to 100 mPa·s, and more particularly 0.1 to 10 mPa·s. It is possible that at least one control unit is configured to control the mutual distance between at least two adjacent spray valves, and preferably control the mutual distance between multiple adjacent spray valves. Adjusting the mutual distance between at least two spray valves allows the primer flow distribution to be optimized. For example, it is possible that at least two adjacent spray valves are positioned such that the primer is applied to the substrate, thereby causing at least partial overlap of the spray jets. In this way, a variable layer thickness of the primer can be formed in a relatively simple and controlled manner. It is also conceivable that at least two spray valves are positioned to apply the primer liquid substantially uniformly and / or consistently onto the substrate.

[0032] In one possible embodiment, at least one control unit is configured to control at least one parameter of at least one resin applicator during the application of resin to at least one substrate, said parameter being selected from the group consisting of: the height of at least one resin applicator, the displacement speed of at least one applicator, the displacement pattern of at least one resin applicator, resin pressure supply, and / or resin flow rate. Specific parameters adjustable by at least one control unit have individual and / or synergistic effects on the pattern and layer thickness of the applied resin. For example, it is possible to adjust at least one parameter based on at least one output characteristic.

[0033] In one possible embodiment, the system, particularly the primer applicator, and more specifically at least one spray valve, includes at least one liquid channel for supplying at least one primer to the at least one spray valve. At least one control unit may be configured to control and / or adjust the size of an opening in the at least one liquid channel supplying the primer to the at least one spray valve. It is also contemplated that at least one primer applicator, particularly its at least one spray valve, is configured to apply at least one primer with a non-uniform thickness distribution to the surface of at least one substrate to be imprinted. This can be achieved, for example, by providing an overlapping spray configuration for at least two spray valves of the at least one primer applicator. It is also possible to control the spray pattern of at least one spray valve, preferably multiple spray valves, by adjusting the size of the channel. It is also possible that at least two (adjacent) spray valves are positioned at different heights relative to the surface to be imprinted. It is also contemplated that non-uniform output, such as a variable layer thickness, can be obtained by individually controlling and / or adjusting at least two spray valves of the primer applicator.

[0034] The system may include at least one carrier for carrying at least one substrate to be imprinted. Alternatively, the carrier may be configured to carry multiple substrates. The system may be configured such that the distance between at least one spray valve and at least one carrier is adjustable. It is also possible that the distance between at least one primer applicator and at least one carrier is adjustable, and / or the distance between at least one resin applicator and at least one carrier is adjustable. This can further optimize control of the primer and / or resin application process. The system may also include at least one transport unit for transporting at least one carrier and / or at least one substrate. The transport unit may, for example, include at least one air cushion, multiple rollers, a belt, an interface with a substrate handler, and / or combinations thereof.

[0035] Preferably, at least one spray valve includes an air atomizing nozzle. Therefore, at least one spray valve may include at least one fan-shaped element configured to optimize the primer jet. It is conceivable that at least one control unit is configured to control and / or regulate the fan-shaped air pressure of at least one fan-shaped element of at least one air atomizing nozzle. The fan-shaped air pressure is the pressure of the air near the primer nozzle opening, which causes the sprayed primer to be atomized or sprayed. Higher fan-shaped air pressure will cause the spray pattern to stretch, for example, become more elliptical. It is also conceivable that at least one control unit is configured to control and / or regulate the orientation of the fan-shaped element of at least one air atomizing nozzle. This can further optimize the control of the primer distribution process.

[0036] The system according to the invention may further include at least one flexible template configured for nanoimprinting, particularly roll-to-roll nanoimprinting. Any embodiment described for the system according to the invention is also applicable to the method according to the invention, and vice versa. The invention also relates to a system for nanoimprinting, comprising at least one flexible template configured for nanoimprinting, particularly roll-to-roll nanoimprinting. Attached Figure Description

[0037] The present invention will be further illustrated by the following non-limiting exemplary embodiments shown in the accompanying drawings, wherein: - Figure 1a and Figure 1b A substrate subjected to a primer application process according to the prior art is shown; - Figures 2a-2d A method for controlled application of a primer and resin to a substrate for roll-to-roll nanoimprinting according to the present invention is shown; - Figure 3 A substrate according to the invention is shown, on which a primer and resin for nanoimprinting are applied; and - Figures 4a-4cA spray valve is shown that is used in the method and system according to the invention.

[0038] In these figures, similar reference numerals correspond to similar or equivalent elements or features. Detailed Implementation

[0039] Figure 1a and Figure 1b Schematic diagrams are shown of a substrate 10 treated with a primer 11 according to the prior art. These figures show a top view of the substrate 10. In the left portion of the figures, the substrate 10 to be imprinted does not contain the primer or resin. The figures then show the substrate 10 with the primer 11 applied by spraying. From Figure 1a As can be seen, the entire surface of the substrate 10 is not covered by the primer liquid. The further primer liquid layer is preferably disposed substantially uniformly on the surface of the substrate 10. Figure 1b As shown, an excessive amount of primer 11 is applied to ensure that the substrate 10 is completely covered by the primer 11.

[0040] Figure 2a , 2b Figures 2c and 2d illustrate schematic diagrams of a method according to the invention for controlled application of a primer and resin to a substrate for roll-to-roll nanoimprinting. All figures show a top view of at least one substrate 110, which is subsequently provided with a primer 11 and a resin 12. Figure 2a A sequence is shown, in which a bare substrate 110 is first shown, followed by the application of a primer 11 to the substrate by spraying using at least one spray valve 120. Typically, the viscosity of the primer 11 is in the range of 0.001 to 1000 mPa·s, particularly 0.01 to 100 mPa·s, and even more particularly 0.1 to 10 mPa·s. The primer 11 is applied to the substrate 110 in a first predetermined pattern, wherein the layer thickness of the applied primer 11 varies by segment. It can be seen that the first primer segment 11a has a first layer thickness, the second primer segment 11b has a second layer thickness, and the third primer segment 11c has a third layer thickness. In the next step, at least one resin 12 is applied to the substrate 110 by droplet application. The resin typically has a viscosity in the range of 0.1 to 50000 mPa·s, particularly 1 to 1000 mPa·s, and even more particularly 10 to 200 mPa·s. Resin 12 is applied to the substrate 110 that has been primed with a second predetermined pattern by a resin droplet applicator 121, the second predetermined pattern overlapping the first predetermined pattern formed by the primer liquid. Figure 2b It shows the relationship with Figure 2aA similar configuration is seen in [the previous section]. However, in this process, the primer 11 is applied in excess to ensure that the substrate 110 is completely covered by the primer 11. Furthermore, the first predetermined pattern is formed by two first primer segments 11a having a first layer thickness, which surround a second primer segment 11b having a second layer thickness. The second layer thickness can, for example, be twice the thickness of the first layer. Figure 2c A substrate 110 is shown, defining multiple sections 110a-110f, namely the effective regions 110a-110f. These specific sections 110a-110f are configured for imprinting, while the rest of the substrate 110 should remain clean. Therefore, a primer 11 is specifically applied to the effective regions 110a-110f of the substrate 110. In the illustrated embodiment, the primer 11 is applied in such a way that the area outside the effective regions 110a-110f has a greater primer layer thickness. These so-called outflow / overflow areas are located outside the effective regions 110a-110f, and applying a thicker primer layer ensures that excess resin 12 adheres to the substrate 110, rather than to the imprinting stencil used for imprinting. The right-hand portion of the figure shows that the resin 12 is applied in droplet form to a portion of the effective regions 110a-110f. The flexible template applied during the roll-to-roll embossing process will spread the resin 12 onto the effective areas 110a-110f during the embossing process. Figure 2d Another embodiment is shown, in which a plurality of substrates 110 are provided and positioned on a carrier 130. A primer 11 is applied with three different layer thicknesses 11a, 11b, and 11c, each substrate 110 having a different thickness. It can be seen that the amount of resin 12 applied is based on the applied primer layer thicknesses 11a, 11b, and 11c.

[0041] Figure 3 Another example of a substrate 210 is shown, in which a primer 11 and resin 12 are applied for nanoimprinting purposes. The figure shows a generally straight and flat substrate 210, on which four effective regions 210a-210d are marked. Resin 12 is spread over the regions that completely cover the effective regions 210a-210d. Primer 11 is applied to a larger area, which is larger than the area defined by resin 12. However, the area defined by primer 11 is smaller than the total area of ​​substrate 210. The boundary of the first predetermined pattern defined by the primer is a distance d1, d2 from the outer edge of substrate 210.

[0042] Figures 4a-4cA spray valve is shown for use in the methods and systems according to the invention. These figures show a schematic representation from a side view. These figures show a spray valve 120 configured to spray a primer 11 onto a substrate, particularly a primer 11 with a viscosity in the range of 0.001 to 1000 mPa·s, especially 0.01 to 100 mPa·s, and more particularly 0.1 to 10 mPa·s. The spray valve 120 may be included in a primer applicator. The spray valve 120 includes a liquid passage 122 or fluid supply line 122 for supplying the primer. The size of at least one opening in at least one of the liquid passage 122 and / or nozzle opening 123 can be adjusted, in particular, by a stroke 124. The spray valve 120 also includes a control air hose 125 and a nozzle fan-shaped air hose 126.

[0043] Figure 4a Two adjacent spray valves 120 are shown, separated by a distance Da (i.e., pitch). The spray valves 120 are configured to spray a generally elliptical jet of primer liquid. Figure 4a In this configuration, the positioning of the spray valve 120 ensures that the primer liquid 11 supplied by adjacent spray valves 120 does not overlap. Figure 4b The configuration shows a small distance Db (i.e., pitch) between adjacent spray valves 120, causing partial overlap of the primer 11 supplied by adjacent spray valves 120. This allows for a greater thickness of the primer 11 layer during a single spray application. Within the scope of the invention, a control unit can be used to control the mutual distance, i.e., the pitch, between at least two adjacent spray valves 120, and preferably between multiple adjacent spray valves 120. Figure 4c The effect of adjusting at least one parameter of the spray valve 120 is shown. The influence of fan-shaped air pressure on the primer spray shape can be seen. Higher fan-shaped air pressure results in a smaller beam H, while lower fan-shaped air pressure results in a wider beam L.

[0044] It should be understood that the present invention is not limited to the exemplary embodiments illustrated and described herein, but numerous variations may exist within the framework of the appended claims, as will be apparent to those skilled in the art. In such cases, it is conceivable that different inventive concepts and / or technical measures of the above-described variant embodiments can be combined, in whole or in part, without departing from the inventive concept described in the appended claims.

[0045] The verb “comprise” and its variations used in this patent document should be understood to mean not only “comprise”, but also expressions such as “contain”, “substantially contain”, “formed by” and their variations.

Claims

1. A method for controlled application of a primer and resin to a substrate for roll-to-roll nanoimprinting, comprising the following steps: At least one primer is applied to at least one substrate by spraying, wherein the viscosity of the at least one primer is in the range of 0.1 to 10 mPa·s; and subsequently At least one resin is applied to the at least one substrate by droplet application, wherein the viscosity of the at least one resin is in the range of 5 to 2000 mPa·s. At least one primer is applied to the at least one substrate in a first predetermined pattern, and at least one resin is applied to the at least one substrate in a second predetermined pattern, wherein at least a portion of the second predetermined pattern overlaps with the first predetermined pattern.

2. The method of claim 1, wherein at least one primer is applied to a predetermined portion of the at least one substrate such that the area defined by the primer is smaller than the total area of ​​the at least one substrate.

3. The method according to any one of the preceding claims, wherein at least a portion of the first predetermined pattern has a non-uniform thickness distribution of the primer liquid.

4. The method according to any one of the preceding claims, wherein at least a portion of at least one primer liquid is applied to the at least one substrate with a layer thickness that can vary.

5. The method according to any one of the preceding claims, wherein at least a portion of the first predetermined pattern is different from at least a portion of the second predetermined pattern.

6. The method according to any one of the preceding claims, wherein at least one primer is applied through at least one spray valve, and preferably through a plurality of spray valves.

7. The method of claim 6, wherein during the application of at least one primer to the at least one substrate, the spray valve height of at least one spray valve, the displacement speed of at least one spray valve, the orientation of at least one spray valve, and / or the displacement pattern of at least one spray valve are controlled and / or adjusted.

8. The method according to any one of the preceding claims, wherein at least one resin is applied via at least one injection valve and / or a piezoelectric actuation valve.

9. The method according to any one of the preceding claims, wherein at least one resin is applied to the at least one substrate in an intermittent pattern.

10. The method according to any one of the preceding claims, wherein the first pattern comprises at least two pattern segments spaced apart from each other.

11. The method according to any one of the preceding claims, wherein at least one primer has a viscosity in the range of 0.3 to 8 mPa·s, preferably in the range of 0.5 to 5 mPa·s, more preferably in the range of 1 to 3 mPa·s.

12. The method according to any one of the preceding claims, wherein at least one resin has a viscosity in the range of 5 to 150 mPa·s, preferably in the range of 10 to 100 mPa·s, more preferably in the range of 15 to 75 mPa·s.

13. The method according to any one of the preceding claims, comprising the step of imprinting at least a portion of the resin.

14. The method according to any one of the preceding claims, wherein at least a portion of the first predetermined pattern is adjacent to at least a portion of the second predetermined pattern, and wherein a transition region exists at at least a portion of at least one side edge of the first predetermined pattern, wherein the transition region is defined as a region in which a portion of the second predetermined pattern adjacent to a portion of the first predetermined pattern transitions into the overlapping portion of the first predetermined pattern and the second predetermined pattern.

15. A system for controlled application of a primer and resin to a substrate, particularly for roll-to-roll nanoimprinting by the method according to any one of the preceding claims, comprising: At least one primer applicator for applying at least one primer to at least one substrate to be imprinted, the primer applicator comprising at least one spray valve configured to spray at least one primer with a viscosity in the range of 0.1 to 10 mPa·s; At least one resin applicator is used to apply at least one resin with a viscosity in the range of 5 to 2000 mPa·s to the at least one substrate by droplet application; as well as At least one control unit is configured to, particularly during the application of a primer to the at least one substrate, control and / or adjust at least two parameters of the at least one primer applicator, wherein the parameters are selected from the group consisting of: the spray valve height of at least one spray valve, the primer flow rate from at least one spray valve, the displacement speed of the at least one primer applicator, the orientation of at least one spray valve and / or the orientation of at least one spray valve, and the displacement pattern of the at least one primer applicator and / or at least one spray valve.

16. The system of claim 15, wherein at least one control unit is configured to control and / or adjust at least one parameter of at least one spray valve, wherein the at least one parameter is selected from the group consisting of: fan-shaped air pressure, primer pressure, spray valve stroke setting, primer flow rate, and / or spray shape.

17. The system of claim 15 or 16, comprising a plurality of spray valves, wherein at least two spray valves are positioned substantially parallel to each other.

18. The system of claim 17, wherein at least one control unit is configured to control the mutual distance between at least two adjacent spray valves.

19. The system according to any one of claims 15 to 18, wherein at least one control unit is configured to control at least one parameter of the at least one resin applicator during the application of resin to the at least one substrate, wherein the parameter is selected from the group consisting of: the height of the at least one resin applicator, the displacement speed of the at least one applicator, the displacement pattern of the at least one resin applicator, and the resin flow rate.

20. The system according to any one of claims 15 to 19, comprising at least one liquid channel for supplying at least one primer liquid to at least one spray valve, wherein at least one control unit is configured to control and / or adjust the size of an opening in the at least one liquid channel for supplying primer liquid to the spray valve.

21. The system according to any one of claims 15 to 20, wherein at least one primer applicator, in particular at least one spray valve thereof, is configured to apply at least one primer having a non-uniform thickness distribution to the surface of at least one substrate to be imprinted.

22. The system according to any one of claims 15 to 21, comprising at least one carrier for carrying at least one substrate to be imprinted.

23. The system of claim 22, wherein the distance between at least one spray valve and at least one carrier is adjustable.

24. The system according to any one of claims 15 to 23, wherein at least one spray valve comprises an air atomizing nozzle.

25. The system according to any one of claims 15 to 24, comprising at least one flexible template for nanoimprinting.

Images