Multi-Texture Stamp

Abstract

The present invention relates to a flexible stamp for use in an imprinting process, the flexible stamp comprising a support including a first surface and at least two spots of flexible material adhered to the first surface of the support and having a surface that is parallel to a front surface of the support and that is textured with an imprinting pattern.

Description

[Technical field]

[0001] The present application relates to a flexible stamp, a method for making the same, and an apparatus for using the flexible stamp.

[0002] The use of functional textured layers (the term "texture" includes, for example, pyramidal, lenticular, prism, cone and flat layers) in devices is an important topic. Such layers can be used appropriately to improve performance, reduce costs or improve the appearance of a product. For example, diffusive layers are used in displays, which allow the use of thin LED backlight concepts that illuminate the display from the side. Other new and cutting-edge possibilities include incorporating functional textured layers into solar panels to improve their efficiency or into organic light-emitting diode (OLED) lighting panels to capture more light.

[0003] Functional texture layers can be produced by the use of UV imprinting. In this case, the substrate, the stamp or both are coated with lacquer (resin or resist). After pressing the stamp against the substrate with the lacquer in between, the textured lacquer is cured to a solid phase. The curing method can be thermal or by the use of UV light. This technique was already mentioned in 1978 in US Pat. No. 4,128,369. Further pioneering work was done by Chou in 1995. He demonstrated that by using a rigid stamp, textures of less than 25 nm can be replicated with high throughput for mass production (US Pat. No. 5,772,905, or the paper by Stephen Y. Chou, Peter R. Krauss and Preston J. Renstrom (Appl. Phys. Lett. 67 (1995) 3114-3116)). It was subsequently demonstrated that textures could be replicated using a roller to apply pressure to a rigid stamp or a bent thin metal sheet (Hua Tan, Andrew Gilbertson, Stephen Y. Chou, J. Vac. Sci. Technol., B 16 (1998) 3926-3928).

[0004] Many research institutes and companies have continued this research, resulting in various technologies. In the semiconductor industry, plate-to-plate imprinting is applied by using a rigid stamp in combination with the transfer process, material and precise positioning, as described in U.S. Pat. No. 6,334,960, U.S. Pat. Appl. Pub. No. 2004 / 0065976, and U.S. Pat. No. 8,432,548. In roll-to-roll imprinting technology, a texture roller is used in combination with a flexible substrate to impart texture to foils or films in a continuous process, as described in U.S. Pat. No. 8,027,086.

[0005] The plate-to-plate technique mentioned above is designed for precise wafer-scale imprinting of small textures (feature sizes below 100 nm) on uniform and flat wafers with high positional accuracy, but as described in Chinese Patent Application No. 103235483, this technique is difficult to scale to large areas.

[0006] Using roll-to-roll technology, textured foils can be produced continuously at high production rates. These textured foils can be used as substrates for flexible applications or laminated to rigid substrates. The latter, however, entails the additional cost of an intermediate adhesive layer to bond the flexible textured foil to the rigid substrate or product. A third new technology is therefore being developed: direct roll-to-plate imprinting. Hereby, a functional textured layer is applied directly to a separate substrate without the use of an auxiliary film with an additional intermediate adhesive layer of tens or hundreds of microns in thickness. In contrast to the plate-to-plate technology, imprinting is performed by using a textured roller or a textured foil, also called a flexible stamp, wrapped around a roller.

[0007] Thus, roll-to-plate imprinting has become established as the standard technique for the direct texturing of large rigid substrates, while plate-to-plate imprinting has become the standard technique for the direct texturing of small rigid substrates.

[0008] In a recent development, roll-to-plate imprinting of small periodic structures has been extended to large substrates by using a small flexible stamp that is repeatedly rolled over the large substrate, as shown in EP 2823356.

[0009] All these developments indicate that roll-to-plate imprinting is evolving into the imprinting technique of choice for large substrates, while small substrates are usually textured by plate-to-plate imprinting.

[0010] However, plate-to-plate imprinting of small substrates is challenging because each substrate typically has a different height. These differences can be small, typically on the order of a few microns or tens of microns. Nevertheless, small height differences at the sharp edges of the substrates can damage the flexible stamp when pressure is applied to it during the roll-to-plate imprinting process.

[0011] Textured regions made of highly sensitive polymers can be severely damaged when contacting the edge of a substrate when imprinting multiple substrates with one flexible stamp, whereas when imprinting a single substrate, the substrate edge can be positioned so that it does not contact the textured region. Damage to the textured region can result in scratches, loose particles, and reduced yields and must be prevented.

[0012] The objective of this paper is to provide a fast and efficient technique for roll-to-plate imprinting on multiple small substrates at once without damaging any part of the flexible stamp.

[0013] This object is achieved by a flexible stamp for use in an imprinting process, the flexible stamp comprising a support having a first surface and at least two spots of flexible material, the spots adhered to the first surface of the support and having a surface, the surface being parallel to the front surface of the support and textured with an imprinting pattern.

[0014] In one embodiment, bonding may also include embossing the support with a flexible material.

[0015] Throughout this application, the term "flexible" means that the material or part thereof has a Young's modulus of 0.1 gigapascals (GPa) to 10 gigapascals (GPa). In one embodiment, the Young's modulus is 0.5 gigapascals (GPa) to 5 gigapascals (GPa). Young's modulus is measured according to ASTM E111.

[0016] Throughout this application, the term "parallel" in relation to two surfaces, planes or regions means that said two surfaces, planes or regions do not intersect or intersect at an angle of up to 6° with respect to each other.

[0017] A stamp according to the present application is any means that can be used for texturing, imprinting or embossing a surface. Typically, the stamp comprises an imprinting surface that is textured with an imprinting pattern of recesses and protrusions, which is then transferred to a substrate. This transfer can be done in three different ways. Firstly, the imprinting surface can be treated with an imprinting material such as ink, colorant or resin, so that only the protrusions pick up the imprinting material and transfer it to the substrate, according to the principle of so-called relief imprinting, which is used for example in clerical stamps and in classical typewriters or in historical book printing with lead type. In all these imprinting processes, only the protrusions of the imprinting surface transfer the imprinting medium to the substrate. Secondly, the imprinting surface can be coated with an imprinting material such as ink, colorant or resin, so that the recesses of the imprinting surface are filled with the imprinting material. The imprinting surface can then be scraped off, for example using a doctor blade, so that only the recesses remain with the imprinting medium, from which it can be transferred to the substrate. If the substrate is paper, this imprinting technique is known as intaglio imprinting. The stamp can also be used to texture spots or layers of a liquid or viscous imprinting medium, such as a resin, lacquer or wax, so that the recesses of the imprinting pattern become protruding areas on the substrate and the protruding areas of the imprinting pattern become recesses on the substrate. This is similar to the use of a sealing matrix with a traditional engraving in a sealing wax or sealing lacquer.

[0018] Third, a stamp can be pressed into a solid but formable surface to emboss a pattern therein, similar to an embossed seal on paper.

[0019] The flexible stamp according to the present application can be used for all the above mentioned imprinting techniques.

[0020] The support according to the present application forms a kind of skeleton of the flexible stamp and can be any flexible material. In one embodiment, the support is a plastic foil, for example of polyethylene terephthalate or other flexible but robust polymeric material. The support can also be a thin sheet, for example a glass sheet, a metal sheet. The support can also be a composite material, for example a thin glass, metal or polymer sheet embedded on or between polymeric materials.

[0021] In another embodiment, the support is a plastic foil or thin sheet or embedded sheet in combination with an adhesive layer thereon, which may in particular be a polymer layer or a pressure sensitive adhesive.

[0022] In one embodiment, the support may be transparent to visible and / or UV light to allow radiation induced curing of the resin through the support.

[0023] In one embodiment, the support may contain a UV protectant to prevent degradation during radiation-induced curing. Possible UV protectants may be from the group of hindered amine light stabilizers (HALS).

[0024] In one embodiment, the support can be heat resistant so that it is not damaged or loses mechanical stability at typical curing temperatures of the curable resin.

[0025] The support comprises a first surface and a second surface. By definition, the first surface is considered to be the surface that is directed towards the substrate during the imprinting process.

[0026] The flexible stamp further comprises at least two spots of flexible polymeric material, the spots being adhered to the first surface of the support. The adhesive connection between the spots and the support can be achieved by an additional adhesive material located between the spots of flexible polymeric material and the first surface of the support, or by an inherent adhesive connection between the polymeric material of the spots and the material of the support. The spots can also comprise multiple layers, with the layer facing away from the first surface of the support being textured with the imprinting pattern.

[0027] A spot according to the present application is an area on a support that is much smaller than the support, which is usually made of a material different from the support and which forms a separate layer on the support. Thus, a spot according to the present application can be interpreted as an area on a support that is smaller than the support and forms a second layer on the support. A spot on a support can also have the form of a coating. A spot can also be a textured piece of foil, for example plastic, glass or thin metal sheet, which is adhesively connected to the support in the manner of a textured label and has a polymer layer on it.

[0028] The spots may be any flexible polymeric material such as polymeric materials based on acrylates, methacrylates, fluorinated acrylates, epoxides, thiols, vinyl-containing monomers, ethers, fluorinated ethers, siloxanes, siloxane-acrylates or blends of two or more of these materials.

[0029] In one embodiment, the flexible polymeric material is selected from polymer classes such as epoxides, thiols, polyvinyl resins, polyethers, fluorinated acrylates, fluorinated methacrylates, fluorinated polyethers, siloxanes, siloxane acrylates, or blends thereof.

[0030] In one embodiment, the material of the spots may be the product of a solidification or hardening process of a material that is contacted with the support in liquid or viscous form and then solidified or hardened while in contact with the support. The materials of the different spots may be the same or different.

[0031] The spots can have an additional intermediate base layer, such as polycarbonate, PET, a thin glass sheet or a thin metal sheet, in which case the combination of the spots and the base layer is glued to the material of the support with an adhesive layer.

[0032] All spots according to the present application have a flat surface parallel to the first surface of the support. The flat surfaces of all spots on the support have the same height, such that the surfaces of the spots are part of one imaginary plane parallel to the plane of the first surface of the support. The surfaces of all spots are at least partially textured with an imprinting pattern that forms recesses and protrusions on the surface of the spots. The recesses may or may not be configured to reach the material of the support throughout the spot. The texture may or may not cover the entire flat surface of the spot. Preferably, the size of the length and width of the spots is large compared to the preferred textured area on the substrate.

[0033] The spots may overlap each other or may be separate from each other. Separate, according to the pending application, means that the spots are completely surrounded by the areas of the support where the "bare" or uncovered material faces the substrate. Thus, the separate spots are like islands on the support.

[0034] The spots may have a regular shape, such as a circle, an ellipse, a rectangle or a polygon, or the shape of the spots may be irregular. The imprinting pattern may have both a size and a shape that deviates from the size and shape of the spots, but the size of the spots will always be at least as large as the size of the imprinting pattern. In one embodiment, the imprinting pattern may be rectangular, while the spots with the imprinting pattern may have a circle, an ellipse or an irregular shape.

[0035] The surface texture of the spots may be the same or different. A flexible stamp according to the present application may have groups of adjacent spots with the same texture. Groups of adjacent spots with the same texture may form lines, rows, diagonals or other types of designs on the substrate. It is also possible for the spots to be randomly arranged.

[0036] According to the pending application, the flexible stamp can be used to texture multiple substrates at once by providing multiple spots on the flexible stamp. This requires providing multiple substrates to the method according to the application, with the substrate surface directly under the textured surface of the spots. Using this approach, multiple small substrates can be textured during one imprinting process. This is advantageous for substrate types that only have small sizes, and it avoids the need to separate large textured substrates, which can cause damage or contamination of the textured surface. Thus, the flexible stamp according to the application can be used to increase the throughput and efficiency of the imprinting process of small substrates, which are typically textured using a plate-to-plate process. Rigid stamps in plate-to-plate processes are much more difficult and expensive to replicate than the flexible stamp according to the application, especially using the methods described below in this application.

[0037] The robust design of the flexible stamp does not limit its use to imprinting a substrate with a single spot of similar size. In an embodiment, the flexible stamp can be used to imprint a substrate covering multiple spots. The imprinting substrate can be of a similar size to the flexible stamp. In such a case, the substrate is imprinted with multiple separate textures, which can be the same, different or part of a periodic texture. The texturing is done by a single pass of the large-scale substrate underneath the flexible stamp. The textured substrate can be further used as is or separated into smaller pieces. This can be a method of multiple replication of a small master on a large substrate.

[0038] The robust design of the flexible stamp does not limit its use for imprinting substrates smaller than a spot: such use is still possible, although yield may be impacted.

[0039] The number of spots on the flexible stamp is not limited.

[0040] When an intermediate adhesive layer is used, the adhesive connection between the spot and the support can be either permanent or reversible. A reversible connection means that the spot can be detached from the support, for example by using a chemical agent such as a solvent, by heating, by mechanical stress or any combination thereof. The detachment can be performed in such a way that the support is not damaged. In one embodiment, the spot can be completely detached from the support, and the support can be reused, for example by gluing a new spot to the support.

[0041] In one embodiment, the polymeric material of the spot has a resistance of 50 mN / m 2In one embodiment, the surface free energy is less than 35 mN / m 2 Less than or equal to 30mN / m 2 In one embodiment, the polymeric material of the spots is selected to exhibit adhesion that allows easy release from hardened resins typically used in imprinting processes using flexible stamps, such as epoxides, thiols, polyvinyl resins, acrylates, methacrylates, polyethers, fluorinated acrylates, fluorinated methacrylates, fluorinated polyethers, siloxanes, siloxane acrylates, or blends thereof.

[0042] The polymeric material of the spots may have anti-adhesive properties. If not, the flexible stamp may be treated with an anti-adhesive treatment before use. Such surface treatment of the flexible stamp may be a plasma treatment or an anti-adhesive coating treatment by a wet process, a vapor process, a gas-phase process or a combination of these processes.

[0043] The support material between the spots and not covered by the spots can have the same low surface free energy as the spots, e.g., 50 mN / m 2 Less than or equal to 35mN / m 2 The support may have a surface free energy of about 100 nm or even less. The low surface energy may be an inherent property of the support material or may be produced on the support material by an additional surface treatment process. Such surface treatment of the support may be a plasma treatment or an anti-stick coating treatment by a wet process, a vapor process, a gas-phase process or a combination of these processes.

[0044] In another preferred embodiment, the support material between the spots and not covered by the spots can have a hard-coated upper surface to protect the flexible stamp from damage by the edges of multiple small substrates processed in a single imprinting step.

[0045] In one embodiment, the surface of the spot is above the first surface of the support. Such a spot is as if added to the support. In one embodiment, the top surface of the spot is above the first surface of the support at a height higher than the depth of the deepest recess of the imprinting pattern. In another embodiment, the surface of the spot is above the first surface at a height higher than the thickness variation of the layer of imprintable medium to be textured by the flexible stamp depending on the application. Both of these embodiments, which can also be combined, have the objective of preventing the material of the support from coming into contact with the imprintable medium.

[0046] In one embodiment, channels are formed between spots on the support. Said channels can be interpreted as boundaries between different spots, and said channels can have a function during the imprinting process, which can be performed using the flexible stamp depending on the application. Either excess imprintable medium or air trapped in the system of flexible stamp, substrate and imprintable medium can escape through said channels. A similar effect to channels can also be achieved by clearing between different spots of material. In contrast to channels, clearings according to the present application are void areas that are larger than channels. In contrast to channels, clearings are more area-like, in contrast to channels, which are more linear. In general, both channels and clearings are void areas, and channels are more linear while clearings are more space-like. Throughout this application, the terms "channel" and "clearing" are used interchangeably, i.e., unless otherwise stated, both terms are meant when either term is used.

[0047] The present application further relates to a method for manufacturing a flexible stamp according to claim 14. In one embodiment, the method further comprises the steps of providing at least one master comprising a textured region, providing a support having a width and length that are the same size as or larger than the width and length of the textured region of the one or more masters, providing a curable resin on the master and / or the support, contacting the support and the master with the resin therebetween, optionally applying pressure to the support such that the resin fills the textured region and forms a layer over the textured region, curing the resin while it is in contact with both the master and the support, separating the support with the cured resin from the master, and moving the at least one master relative to the contact surface and in a plane parallel to the plane of the support or vice versa, the steps of contacting the support and the master with the resin, applying pressure to the support, curing the resin and separating the support with the cured resin from the master being performed at least twice.

[0048] The support according to the present application forms a kind of skeleton for the flexible stamp to be produced and can be any flexible material. In one embodiment, the support is a plastic foil, for example of polycarbonate, polyethylene terephthalate or other flexible but robust polymeric material. The support can also be a thin glass sheet, a thin metal sheet or a composite material, for example of a thin piece embedded in one or more polymeric materials.

[0049] In one embodiment, the support may be transparent to visible and / or UV light to allow radiation induced curing of the resin through the support.

[0050] In one embodiment, the support may contain a UV protectant to prevent degradation during radiation-induced curing. Possible UV protectants may be from the group of hindered amine light stabilizers (HALS).

[0051] In one embodiment, the support can be heat resistant so that it is not damaged or loses mechanical stability at typical curing temperatures of the curable resin.

[0052] The master is typically a rigid flat plate of a durable material. In one embodiment, the master may be made of a metal such as steel, nickel, copper or aluminum. In one embodiment, the master may be made of silicon, quartz or glass. In one embodiment, the master may be a plastic foil or sheet. In one embodiment, the master is a silicon wafer. The master can have any shape, such as a circle, oval, rectangle, triangle, polygon or irregular shape.

[0053] The master includes a textured region. The textured region is a region on the surface of the master that includes recesses and protrusions that form a texture, which may be regular or random and may form any type of drawing, image or pattern. The textured region may be formed by engraving into the surface of the master by any engraving technique, such as milling. Other techniques include, but are not limited to, laser ablation, grayscale lithography, wafer-scale lithography and etching. The textured region has a surface area that is at most half the surface area of ​​the support. The textured region may have any shape, such as rectangular, triangular, polygonal, circular, elliptical or irregular. The textured region may have a different shape than the master. The textured region may be smaller than the master. Thus, for example, a rectangular textured region may be provided inside a circular master.

[0054] The master can include detection markers. A detection marker according to the present application is a structure that is detected by a detection system, e.g., with a camera and a computer, so that the location and orientation of the master can be precisely determined. A detection marker can be a specific pattern that can be engraved into the surface of the master, or that can be drawn or painted on the master, e.g., with permanent ink. A detection marker can also be a small piece of material that is visually different from the material of the master and that is glued, welded or soldered to the master.

[0055] To allow easy separation of the support with the cured resin from the master, the master can be treated with an anti-sticking agent before being fed to the method for producing a flexible stamp. Possible anti-sticking agents can include low-viscosity silicone oils, paraffin oils, fatty oils, aliphatic surfactants, fluorinated surfactants, aliphatic siloxanes, fluorinated phosphonic acids, siloxanes or aliphatic or fluorinated silanes. For the proper performance of the method for producing a flexible stamp, it is necessary that the anti-sticking agent and the curable resin on the master do not mix with each other. The surface of the master, including the textured areas, can have a surface free energy of at most 50 mN / m. In one embodiment, the surface free energy of the master's surface, including the textured areas, is at most 35 mN / m. In another embodiment, the surface free energy of the master's surface, including the textured areas, is at most 25 mN / m or at most 15 mN / m.

[0056] The curable resin can be applied to the master and / or the support by any possible dispensing technique, such as dip coating, dripping, slit coating, roll coating, waterfall coating, spray coating, deposition or inkjet printing. The curable resin can be applied directly to the master or it can be coated on the support and then applied to the master when the support is in contact with the master. The curable resin can be dispensed in a controlled manner either to the master or to the support, to avoid on the one hand overflow of the resin and on the other hand to ensure the formation of a resin layer covering the textured areas. In an embodiment, the curable resin can be applied to the master as one or more droplets, puddles, lines, circles, ellipses or any other geometric dispensing pattern that is dispensed after application. One or more droplets can be arranged on the master and / or the support such that, upon application, a layer is formed covering the textured areas of the master. The curable resin may be selected from the group consisting of epoxides, thiols, monomers for polyvinyl resins, acrylates, methacrylates, polyethers, fluorinated acrylates, fluorinated methacrylates, fluorinated polyethers, siloxanes, siloxane acrylates, or blends thereof.

[0057] The support is brought into contact with the resin on the master. In one embodiment, the method steps are performed such that the support and the master are not in direct contact, but the resin forms a layer that separates the support and the master from each other. By adjusting the distance between the support and the master, the thickness of the resin layer between the support and the master can be adjusted and the distribution of the resin can be controlled. The smaller the distance between the master and the support is selected, the thinner the resin layer will be. The resin can be selected such that after curing, the resin forms strong adhesion with the material of the support, but on the other hand does not form adhesion with the surface of the master.

[0058] The support is brought into contact with the resin on the master, such that the resin fills the textured areas of the master and forms a layer over the textured areas. Depending on the viscosity of the resin, the pressure on the support and the resin may cause the resin to overflow onto the master including the textured areas, and this flow of resin plays an important role in distributing the resin. Thus, pressure can be applied in a very well controlled manner to control the flow of the resin. For example, pressure can be applied using rollers equipped with a means of applying pressure in a very well controlled manner, such as a linear motor or a hydraulic or pneumatic press.

[0059] The resin is cured while it is in contact with both the master and the support. Curing can be performed in any way known to those skilled in the art, such as thermal curing, where the system of master, resin and support is heated to a curing temperature, for example using an oven or infrared heating. Thermal curing is simplified if either the master or the support has a high thermal conductivity, as for example many metals have. Curing can also be performed using visible or ultraviolet light emitted by a suitable lamp. Curing with visible or ultraviolet light is only possible if at least the master or the support is transparent to visible or ultraviolet light, as for example the support is a polymer foil or the material of the master is quartz. Curing while the master and the support are in contact with the resin ensures that the resin is cured in a shape that corresponds to the shape of the textured areas of the master.

[0060] After curing is complete, the support is separated from the master with the cured resin still adhering to the support, forming a spot of cured resin on the support, which can have at least the size of the textured area and up to the size of the master.

[0061] After the support has been separated from the master, the master is moved relative to the support and in a plane parallel to the plane of the support, for example by moving the master on a stage, or by moving the support while the master remains fixed on a stage or mount, such that the support shifts at least by the extension of the textured region in the shift direction.

[0062] The movement of the master can be performed, for example, by using a robot, such as a delta robot, which places the master in a predetermined position, for example, on a stage. The master can also be attached to a mount that is movable in at least one direction and can be positioned, for example, by using a stepper motor or a servo motor. The movement of the master can be controlled by an optical detection device, such as a camera, connected to a computer that can also be connected to the robot that moves the master. Detection markers on the master can be tracked by the camera to ensure that the master is properly positioned and oriented.

[0063] Additionally, the position of the flexible stamp can be monitored, for example using an optical detection device, allowing the position of the master to be located relative to the position of the flexible stamp.

[0064] After the transfer, the steps of supplying resin to the master, contacting the support with the resin on the master and / or the support, possibly applying pressure, curing the resin, and separating the support with the cured resin from the master are repeated to form a second spot on the support after the support with the cured resin is again separated from the master. In one embodiment, the second spot is distinct from the first spot. Depending on the size of the master and the support and the number of spots on the support required, this process can be repeated as many times as necessary, shifting the master at least by the extension of the textured area in the shift direction. Each time this process is performed, a new spot is formed on the support, thus resulting in a flexible stamp with a large number of spots with molded images of the textured areas of the master.

[0065] The polymer material and / or support of the spot is 50 mN / m 2 If the support does not have a surface free energy less than 0.1 mm, an additional anti-stick treatment can be applied after detaching the support from the master having one or more spots.

[0066] In the roll-to-plate process, a roller is used to bring the support into contact with the master, with resin between the master and the support. During imprinting with the roll-to-plate imprint process, either the roller moves, or the support and master move with resin between them, or both move in the opposite direction. To avoid frictional hick-ups between the moving roller, or the moving support and master with resin between them, it is suggested to either drive the movement of the support and / or master, or to move the center point of the roller axis, but in all cases the roller is a free-rolling roller. The rotation of the roller is not actively driven.

[0067] The present invention further relates to an apparatus for manufacturing a flexible stamp, the apparatus comprising a stage for receiving at least one master, at least one roller, a flexible sheet-like material, means for curing a curable resin, means for moving the master over the stage, and means for selectively dispensing the curable resin onto the master and / or the flexible sheet-like material.

[0068] Flexible stamps can also be manufactured by a cut-and-paste process, where multiple available flexible stamps or masters are cut or machined into spots of the desired size, also called tiles, which are then grouped and pasted onto a support foil. The spots can already have anti-stick properties or the anti-stick properties can be added in a downstream anti-stick process.

[0069] In another downstream process, additional material can be provided in the areas between the spots. The material added between the spots or tile areas serves to protect the surface areas at these locations from mechanical or other damage or contamination. This material can consist of an anti-stick material, or a hard coat resin or lacquer. The method of adding the material can be any dispensing process, such as a printing process. [Brief description of the drawings]

[0070] [Figure 1] FIG. 1a illustrates a fundamental problem with the roll-to-plate imprint process, and FIG. 1b illustrates a solution to said problem by providing two separate spots of polymer material 102B that do not contact the edge of the substrate. [Diagram 2] FIG. 2a shows a flexible stamp having a support 102 with four spots of polymer material 201 each having a textured layer 202, and FIG. 2b shows a flexible stamp having a support 102 with four spots of polymer material 201 each having a textured region 202. [Diagram 3] FIG. 1 shows the design of a flexible stamp according to the proposed solution, consisting of a support 102 with four spots, each consisting of a foil 301 with a polymeric overlayer 303 . [Figure 4] FIG. 1 shows an apparatus for manufacturing a flexible stamp with multiple spots from one master according to the proposed solution.

[0071] Figure 1a shows the basic problem of the roll-to-plate imprint process, in which a flexible stamp 102 having a support 102A and a textured layer 102C in polymer material 102B is brought into contact with resin 104 on two different substrates 103 by the use of a roller 101. These substrates have different substrate heights, which can result in angular contact at the contact area 105 and damage the fragile polymer layer 102B. In Figure 1b, this problem is solved by providing two separate spots of polymer material 102B that do not contact the edges of the substrate.

[0072] Figure 2 shows different flexible stamp designs according to the proposed solution. Figure 2a shows a flexible stamp with a support 102 with four spots of polymer material 201, each with a textured layer 202. This textured layer has the inverse of the preferred texture, also called active area, on the substrate. Figure 2b shows a flexible stamp with a support 102 with four spots of polymer material 201, each with a textured area 202. Between the spots of polymer material 201 a method optimization material 203 is added. This can be a hard coat material or a material with anti-stick properties.

[0073] 3 shows the design of a flexible stamp according to the proposed solution, which consists of a support 102 with four spots, each consisting of a foil 301 with a polymer top layer 303. The polymer layer 303 has a textured layer 302.

[0074] Fig. 4 shows an apparatus for manufacturing a flexible stamp with multiple spots from one master according to the proposed solution. A master 401 with textured areas 401A is placed on an imprint stage 402, which supports the master 401 in the imprint process and transports it through the apparatus using a glider 403, where the imprint direction is indicated by an arrow. The position of the master 401 can be adjusted by a robot 412. In this figure, a dispensing tool 410 prints resin droplets 409 on the master. The master 401 with resin 409 is brought into contact with a support 404 by a lamination roller 408A, forming a polymer layer 404A with a textured layer 404B. In this case, the support is held by two clamps 405A and 405B attached to two belts 406. The movement of the support is driven by the belts. In the next step, the polymer layer 404A is cured with UV light from a UV light source 411 and a peel roller 408B is used to remove the support 404 with the polymer layer 404A and the textured layer 404B from the master 401. This process can be repeated after the imprint sledge 402 and master 401 are returned to their initial positions. Before a new cycle, the master 401 can be repositioned by the robot 412.

Claims

1. A flexible stamp (102) for use in an imprinting process, said flexible stamp (102) comprising: a support (102A) comprising a first surface; At least two spots of flexible material (201, 301, 303); wherein the spot comprises - spaced apart from each other and attached to the first surface of the support (102A); and - has a surface, said surface comprising: above the first surface of the support (102A), - parallel to the front face of said support (102A), and textured with an imprinting pattern (202, 302), said imprinting pattern (202, 302) having a size smaller than the size of said spots; Flexible stamp (102).

2. The flexible stamp (102) of claim 1, wherein the flexible material is a polymeric material.

3. The flexible stamp (102) of claim 1, wherein the surface of the spot is located above the first surface of the support (102A) at a position higher than the depth of the deepest recess of the imprinting pattern (202, 302).

4. The flexible stamp (102) of claim 1, wherein all the spots have the same texture.

5. The flexible stamp (102) of claim 1, wherein the spots are reversibly adhered to the support (102A).

6. The polymer material of the spot has a resistance of 50 mN / m ２ , preferably 35 mN / m ２ , and even more preferably 30 mN / m ２ The flexible stamp (102) of claim 1 having a surface free energy of:

7. 10. The flexible stamp (102) of claim 1, wherein the flexible polymeric material is selected from the group consisting of epoxides, thiols, polyvinyl resins, acrylates, methacrylates, polyethers, fluorinated acrylates, fluorinated methacrylates, fluorinated polyethers, siloxanes, siloxane acrylates, or blends thereof.

8. The flexible stamp (102) of claim 1, wherein at least one spot comprises multiple layers.

9. 9. The flexible stamp (102) of claim 8, wherein at least one layer is a thin glass sheet, a thin metal sheet or a thin layer of polymer material, more particularly a thin layer of polycarbonate or polyethylene terephthalate.

10. The flexible stamp (102) of claim 1, wherein the flexible stamp includes channels or other void areas between the spots on the support (102A).

11. The flexible stamp (102) of claim 1, wherein the areas between the spots are filled with additional material.

12. The flexible stamp (102) of claim 11, wherein the additional material is an anti-stick material or a hard coat resin.

13. 13. A method for manufacturing a flexible stamp (102) according to any one of claims 1 to 12, said method comprising the steps of: a. providing at least one master including a textured region; b. Providing a support (102A); c. providing a curable resin on the master or the support (102A); d. Bringing said support (102A) and said master into contact with said resin therebetween; e. Optionally, applying pressure to the support (102A), the pressure being applied so that the resin fills the textured area and forms a layer over the textured area; f. Curing the resin while it is in contact with both the master and the support (102A); g. Separating the support (102A) with the cured resin from the master; h) moving said at least one master relative to a contact surface and in a plane parallel to the plane of said support (102A); Including, - by carrying out steps d) to g) at least twice, a flexible stamp (102) is obtained, said flexible stamp (102) comprising a support (102A) comprising a first surface and at least two spots of flexible material, said spots being spaced apart from one another and adhering to said first surface of said support (102A), and having a surface, said surface comprising: above the first surface of the support (102A), - parallel to the front face of said support (102A), and A method in which the surface is textured with an imprinting pattern (202, 302), said imprinting pattern (202, 302) having a size smaller than the size of said spots.

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