Thermoplastic unidirectional tape with discontinuous coating layer

Abstract

This specification describes unidirectional tapes and methods for manufacturing the same. The unidirectional tapes disclosed herein include a unidirectional fiber layer and a discontinuous coating layer having a plurality of discontinuous coating regions on at least one side of the unidirectional fiber layer.

Description

[Technical Field] 【0001】 Cross-reference of related applications This application claims priority to U.S. Provisional Patent Application No. 63 / 469,997, filed on 31 May 2023, the entirety of which is incorporated herein by reference. 【0002】 This disclosure relates to unidirectional tapes and methods for manufacturing such unidirectional tapes. More specifically, to unidirectional tapes having a discontinuous coating layer on at least one side of a unidirectional fiber layer, and methods for manufacturing the same. [Background technology] 【0003】 Unidirectional tape (UD tape) is a composite material with reinforcing fibers aligned in one direction, typically impregnated with a polymer resin. Compared to conventional materials (e.g., aluminum, steel, and various alloys thereof), UD tape offers various structural advantages, such as lower mass and higher rigidity and strength. Thus, UD tape is used in a wide range of applications, including the aerospace, automotive, and consumer electronics industries. Subsequent processing of these UD tapes may include tacking, tape placement, tape laying, compaction, or welding. Specifically, UD tapes are often heated, which melts and / or softens the polymer of the tape, allowing adjacent layers of the tape to bond or laminate. The ease or difficulty of subsequent processing of UD tapes may depend on various properties of such UD tapes. [Overview of the project] 【0004】 This specification discloses unidirectional tapes with improved processability and moldability, as well as methods for manufacturing them. Typically, the use of unidirectional tapes involves melting the polymer resin in the UD tape and assembling a continuous stack or laminate of multiple plies by, for example, stamp molding, thermoforming, and other lamination techniques (e.g., automated fiber placement (AFP), automated tape layup (ATL), etc.). The UD tapes disclosed herein can improve processability and moldability in such processes. Specifically, the unidirectional tapes disclosed herein may include a discontinuous coating layer on at least one side of a unidirectional fiber layer substrate. The discontinuous coating layer may include a plurality of discontinuous coating regions on at least one side of the unidirectional fiber layer substrate. In some embodiments, the discontinuous coating layer may reduce friction between adjacent plies (ply-ply friction), improve or maintain degassing efficiency by maintaining interply channels, improve or maintain thermal and electrical conductivity (e.g., Z conductivity) between plies, and / or improve tackiness during layup. In some embodiments, the unidirectional tape includes a unidirectional fiber layer comprising a plurality of unidirectional fibers and a first polymer; and a discontinuous coating layer comprising a second polymer and comprising a plurality of discontinuous coating regions on at least one side of the unidirectional fiber layer. In some embodiments, the discontinuous coating layer covers 5 to 75% of the surface area on at least one side of the unidirectional fiber layer. In some embodiments, the thickness of the unidirectional tape has a coefficient of variation (CoV) of 5 to 50%. In some embodiments, the first polymer and / or the second polymer includes polyaryl ether ketone (PAEK), polyphenylene sulfide (PPS), polyether sulfone (PES or PESU), polyethyleneimine (PEI), or a combination thereof. In some embodiments, the first and second polymers are identical. In some embodiments, the plurality of unidirectional fibers include carbon fibers, glass fibers, or a combination thereof. In some embodiments, the discontinuous coating layer includes additives such as conductive additives. In some embodiments, the conductive additive includes carbon particles. In some embodiments, the carbon particles have a volume-distributed mean diameter of 10 to 50 microns. In some embodiments, the discontinuous coating layer contains 2 to 10 mass% of carbon particles. In some embodiments, the unidirectional fiber layer contains additives such as conductive additives. In some embodiments, the conductive additives include carbon black, graphene, carbon nanotubes (CNTs), milled carbon fiber, milled carbon fiber prepreg, or a combination thereof. In some embodiments, the conductive additive has a volume-distributed average diameter of 20 nanometers to 1 micron. In some embodiments, the unidirectional fiber layer contains 0.1 to 10 mass% of conductive additives. In some embodiments, the unidirectional tape has an adhesiveness measured by average or maximum weld strength, which is at least about 500 lb / in. In some embodiments, the unidirectional tape has a ply-ply slip, which results in a wrinkle-free laminate surface.In some embodiments, the unidirectional tapes disclosed herein have ply-ply slip, which reduces ply-ply friction by up to 70% compared to tapes without coating. In some embodiments, the unidirectional tapes disclosed herein may have a maximum porosity of about 0.01 to 6%. 【0005】 In some embodiments, a method for manufacturing a unidirectional tape includes the steps of: preparing a unidirectional fiber layer comprising a plurality of unidirectional fibers and a first polymer; discontinuously coating at least one side of the unidirectional fiber layer with a plurality of particles comprising a second polymer; heating the plurality of particles so that they integrate on at least one side of the unidirectional fiber layer to form a plurality of discontinuous regions; and pressurizing at least one side of the coated unidirectional fiber layer to form a unidirectional tape. In some embodiments, the plurality of particles have an average particle diameter of about 5 to 500 microns. In some embodiments, the method includes pressurizing at least one side of the coated unidirectional fiber layer with a pressure of 0.1 to 10 N / mm. In some embodiments, discontinuously coating at least one side of the unidirectional fibers with a plurality of particles includes electrostatically arranging the plurality of particles. 【0006】 In this specification, the singular forms “a,” “an,” and “the” are intended to include the plural form unless explicitly indicated by the context. The term “and / or” in this specification should also be understood to refer to and include any and all possible combinations of one or more related enumerated items. The terms “includes,” “including,” “comprises,” and / or “comprising” as used herein specifically mention the presence of the described features, integers, processes, operations, elements, components, and / or units, but should be further understood not to exclude the presence or addition of one or more other features, integers, processes, operations, elements, components, units, and / or groups thereof. The aspects and embodiments described herein are understood to include "consisting of" and / or "consisting essentially of." For all methods, systems, compositions, tapes and apparatus described herein, these methods, systems, compositions, tapes and apparatus may include the listed components or steps, or may "consist of" or "consisting essentially of" the listed components or steps. If a system, composition, tape or apparatus is described as "consisting essentially of" the listed compositions, the system, composition, tape or apparatus may include the listed components and other components that do not substantially affect the performance of the system, composition, tape or apparatus, but none of them shall include any other components other than those explicitly listed that substantially affect the performance of the system, composition, tape or apparatus; or they shall not include any extra components in a concentration or amount sufficient to substantially affect the performance of the system, composition, tape or apparatus. If a method is described as "consisting essentially of" the listed steps, this method may include the listed steps and other steps that do not substantially affect the results of this method, but this method shall not include any other steps other than those explicitly listed that substantially affect the results of the method. In this disclosure, "substantially free" of a particular component, particular composition, particular compound, or particular component in various embodiments means that the particular component, particular composition, particular compound, or particular component is present in amounts of less than about 5% by mass, less than about 2% by mass, less than about 1% by mass, less than about 0.5% by mass, less than about 0.1% by mass, less than about 0.05% by mass, less than about 0.025% by mass, or less than about 0.01% by mass. Preferably, "substantially free" of a particular component, particular composition, particular compound, or particular component means that the particular component, particular composition, particular compound, or particular component is present in amounts of less than about 1% by mass. Further advantages will be readily apparent to those skilled in the art from the detailed description below. The examples and descriptions herein are illustrative in nature and do not limit the invention. 【0007】 Referring to the accompanying drawings, various embodiments will be described by way of example only. 【Brief Description of the Drawings】 【0008】 [Figure 1A] FIG. 1A is an example of a cross-sectional view of a unidirectional tape according to some embodiments disclosed herein. [Figure 1B] FIG. 1B is an example of a cross-sectional view of a unidirectional tape having a continuous coating layer according to some embodiments disclosed herein. [Figure 2] FIG. 2 is an example of a cross-sectional view of a unidirectional tape having an additive according to some embodiments disclosed herein. [Figure 3A] FIG. 3A is an example of a top view of a UD tape without a coating layer at 200x magnification according to some embodiments disclosed herein. [Figure 3B] FIG. 3B is a cross-sectional view of a UD tape without a coating layer at 500x magnification according to some embodiments disclosed herein. [Figure 4A] FIG. 4A is an example of a top view of a UD tape having a thin coating layer at 200x magnification according to some embodiments disclosed herein. [Figure 4B] FIG. 4B is a cross-sectional view of a UD tape having a thin coating layer at 500x magnification according to some embodiments disclosed herein. [Figure 5A] FIG. 5A is an example of a top view of a UD tape having an intermediate coating layer at 200x magnification according to some embodiments disclosed herein. [Figure 5B] FIG. 5B is a cross-sectional view of a UD tape having an intermediate coating layer at 500x magnification according to some embodiments disclosed herein. [Figure 6A] FIG. 6A is an example of a top view of a UD tape having a thick coating layer at 200x magnification according to some embodiments disclosed herein. [Figure 6B]Figure 6B is a cross-sectional view at 500x magnification of a UD tape having a thick coating layer according to some embodiments disclosed herein. [Figure 7A] Figure 7A is an enlarged and reduced portion of an image of a 15 mm wide UD tape for calculating the roughness (CoV) according to some embodiments disclosed herein. [Figure 7B] Figure 7B is an example of the black and white threshold of Figure 7A according to some embodiments disclosed herein. DETAILED DESCRIPTION OF THE INVENTION 【0009】 In the figures, like references refer to like components unless otherwise noted. 【0010】 In this specification, unidirectional tapes with improved processing and formability in processes such as, in particular, stamping, thermoforming and other advanced lamination techniques (e.g., automated tape laying (ATL) and automated fiber placement (AFP)), and methods of manufacturing unidirectional tapes are described. To achieve improved processing and formability, one or both surfaces of the unidirectional fiber layer substrate of the UD tape can be modified by applying a partial coating to the surface. This partial coating is a discontinuous coating having a plurality of discontinuous coating regions on the unidirectional fiber layer substrate, and is not a continuous coating on the unidirectional fiber layer substrate or no coating on the unidirectional fiber layer. Specifically, the applicant has discovered that a specific amount of surface area coverage and / or surface roughness disclosed herein for the discontinuous coating layer of the UD tape can balance between (1) improved adhesion (for excellent stack positioning) and reduced ply-ply slip / friction or ply-mold slip / friction (for improved part forming); (2) maintain or keep a ply-channel degassing path between the first ply and the mold and / or between two plies, while (3) having a low porosity, and (4) maintaining excellent electrical conductivity and / or thermal conductivity in the next lamination. 【0011】 To manufacture a unidirectional tape, a unidirectional fiber layer may be prepared. In some embodiments, the unidirectional fiber layer may be a base layer, substrate layer and / or core layer for the discontinuous coating layer disclosed herein. In some embodiments, the unidirectional fiber layer may include a layer of fibers (e.g., reinforcing fibers). In some embodiments, the unidirectional fiber layer may include a plurality of unidirectional fibers. In some embodiments, the unidirectional fibers of the fiber layer (and the unidirectional fiber layer) may be arranged to be unidirectionally oriented. In some embodiments, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, or at least 98% of the fibers of the unidirectional fiber layer may be unidirectionally oriented. The types of fibers used in the unidirectional tapes disclosed herein are not particularly limited or restricted. In some embodiments, the fibers may include glass fibers, carbon fibers, graphite fibers, aramid fibers, boron fibers, alumina fibers, silicon carbide fibers, or combinations thereof. In some embodiments, the unidirectional fiber layer may comprise at least one polymer. In some embodiments, multiple unidirectional fibers may be embedded in and / or dispersed within at least one polymer. In some embodiments, the at least one polymer may be a polymer resin such as a pure (neat) polymer resin or a polymer resin compounded with additives disclosed herein. In some embodiments, the at least one polymer may comprise multiple polymer particles. In some embodiments, at least one polymer may be a thermoplastic polymer. In some embodiments, at least one polymer may be a polyamide, polycarbonate, polyacetal, polyphenylene oxide, polyphenylene sulfide, polyaryllate, polyester, polyamide-imide, polyimide, polyetherimide, polyimide having a phenyltrimethylindan structure, polysulfone, polyethersulfone, polyetherketone, polyetheretherketone, polyaramid, polyethernitrile, polybenzimidazole, or a combination thereof. In some embodiments, at least one polymer may be polyaryletherketone (PAEK), polyphenylene sulfide (PPS), polyethersulfone (PES or PESU), polyethyleneimine (PEI), polysulfone (PSU), or a combination thereof. In some embodiments, at least one polymer may include polyether-ketone (PEK), polyether-ether-ketone (PEEK), polyether-ether-ketone-ketone (PEEKK), polyether-ether-ketone-ketone (PEKK), polyether-ketone-ether-ketone-ketone (PEKEKK), polyether-ether-ketone-ether-ketone (PEEKEK), polyether-ether-ether-ketone (PEEEK), and polyether-diphenyl-ether-ketone (PEDEK), polyarylether-ketone (PAEK) polymer materials having reactive (terminal) groups, or combinations thereof. In some embodiments, the PAEK polymer may include various variants commonly referred to as low-melting-temperature polyarylether-ketones (LMPAEK®), which may have lower melting temperatures and faster processing compared to other PAEK polymers such as PEEK and PEKK, while possessing comparable mechanical properties. 【0012】 In some embodiments, the unidirectional fiber layer may contain additives. As described above, in some embodiments, at least one polymer may be mixed with the additive. In some embodiments, the additive may improve the performance of the compacted laminate, for example. In some embodiments, the additive may be a combination of conductive, dielectric, nonconductive, and / or other types of additives. In some embodiments, the additive may provide properties other than conductive or in combination with conductive properties. In some embodiments, the additive may be added to impart insulating, thermal, chemical, and / or mechanical properties. For example, the additive may be added to impart strength, toughness, thermal stability, CTE, and / or resistance to environmental degradation. In some embodiments, the additive may be a conductive additive to improve the conductivity of the unidirectional fiber layer. For example, the conductive additive may include carbon particles, carbon black, graphene, carbon nanotubes (CNTs), milled carbon fibers, milled carbon fiber prepregs, or a combination thereof. In some embodiments, the additive may have a characteristic length or diameter of about 20 nm to 1 micron. In some embodiments, the characteristic length may be the primary dimension of the additive. In some embodiments, the additive may be mixed and / or melt-mixed with at least one polymer before impregnation. In some embodiments, the additive (and at least one polymer) can be well dispersed in the unidirectional fiber layer. In some embodiments, the amount (or concentration) of the additive may depend on how well the additive is dispersed in the unidirectional fiber layer. For example, the amount (or concentration) of penetration may depend on how well the additive is dispersed in the unidirectional fiber layer. As the degree of dispersion of the additive improves, the additive concentration / amount required to achieve a conductive penetration threshold concentration may decrease. In some embodiments, the unidirectional fiber layer may contain at least about 0.001% by mass, at least about 0.1% by mass, at least about 0.5% by mass, at least about 1% by mass, at least about 2% by mass, at least about 5% by mass, at least about 7% by mass, or at least about 9% by mass of the additive (e.g., conductive additive and / or other additives). In some embodiments, the unidirectional fiber layer may contain at most about 15% by mass, at most about 12% by mass, at most about 10% by mass, at most about 8% by mass, at most about 6% by mass, at most about 5% by mass, at most about 3% by mass, or at most about 1% by mass of additives (e.g., conductive additives and / or other additives). In some embodiments, the unidirectional fiber layer may contain about 0.1 to 10% by mass of additives (e.g., conductive additives and / or other additives). 【0013】 In some embodiments, a unidirectional fiber layer can be prepared by impregnating a plurality of unidirectional fibers (i.e., fiber layers) with at least one polymer (and additives). The impregnation of the fiber layer can be carried out using any technique known to those skilled in the art, including wet methods and hot-melt methods (i.e., dry methods). In some embodiments, the hot-melt method can be used to melt the polymer using an extruder and impregnate the fiber layer (e.g., reinforcing fibers). In some embodiments, the impregnation of the fiber layer can be carried out in an impregnation tank (e.g., a container or vessel having an impregnation slurry / solution). In some embodiments, the fiber layer can be impregnated with the impregnation slurry / solution by moving or drawing the fiber layer through the impregnation tank. In some embodiments, a unidirectional fiber layer can be formed by impregnating the fiber layer with at least one polymer. In some embodiments, the wet method may involve immersing the fiber layer (e.g., reinforcing fibers) in an impregnation slurry or solution containing at least one polymer. In some embodiments, the impregnation slurry or solution may contain at least one primary particle and at least one secondary particle, as described in International Publication No. 2022043391 of the PCT, which is incorporated herein in its entirety by reference. In some embodiments, at least one polymer can be mixed and / or melted in a slurry / solution in at least one solvent such as water, methyl ethyl ketone and / or alcohol (e.g., methanol), and then the fiber layer can be immersed in the slurry / solution. After immersion, the solvent is removed by evaporation (e.g., in an oven) to obtain a unidirectional fiber layer. In some embodiments, the hot melt method may include the steps of applying at least one polymer (and additives) by melting it using an extruder, then coating the fiber layer with at least one polymer, and then heating and pressurizing the at least one polymer layer / coating and the fiber layer to impregnate the fiber layer with the at least one polymer. 【0014】 After preparing or providing a unidirectional fiber layer, a discontinuous coating layer may be applied to at least one side / surface of the unidirectional fiber layer. In some embodiments, the unidirectional fiber layer (one or both sides / surfaces of the layer) may be discontinuously coated with at least one polymer. In some embodiments, the at least one polymer may consist of multiple particles. In some embodiments, the discontinuous coating layer is applied to both sides of the unidirectional fiber layer. The discontinuous coating layer may consist of multiple discontinuous coating regions on the surface of the unidirectional fiber layer. For example, the multiple discontinuous coating regions may be regions separated by gaps between the coating material (e.g., polymer and / or additives) on the surface of the unidirectional fiber layer. The multiple discontinuous coating regions may be arranged on the unidirectional fiber layer so as not to come into contact with other coating regions. In other words, the discontinuous coating layer may have a "sea-island" configuration, where the separated coating regions of the coating layer are islands protruding from the surface (i.e., the sea) of the unidirectional fiber layer. Figure 1A shows a cross-sectional view of a unidirectional tape 100 having a unidirectional fiber layer 101 and a discontinuous coating layer 102, with discontinuous coating regions 103 on both sides of the unidirectional fiber layer. Unlike the unidirectional tapes disclosed herein, Figure 1B shows an example of a continuous coating layer 104 on both sides of the unidirectional fiber layer 101. In some embodiments, at least one polymer of the discontinuous coating layer may be any polymer disclosed herein, including those used to prepare the unidirectional fiber layer. In other words, at least one polymer of the discontinuous coating layer may be a polymer resin such as a pure (neat) polymer resin or a polymer resin mixed with additives disclosed herein. In some embodiments, at least one polymer of the discontinuous coating layer may be a plurality of polymer particles. 【0015】 In some embodiments, at least one polymer in the discontinuous coating may be a thermoplastic polymer. In some embodiments, at least one polymer may be a polyamide, polycarbonate, polyacetal, polyphenylene oxide, polyphenylene sulfide, polyalylate, polyester, polyamide-imide, polyimide, polyetherimide, polyimide having a phenyltrimethylindan structure, polysulfone, polyethersulfone, polyetherketone, polyetheretherketone, polyaramid, polyethernitrile, polybenzimidazole, or a combination thereof. In some embodiments, at least one polymer may be a polyamide, polycarbonate, polyacetal, polyphenylene oxide, polyphenylene sulfide, polyalylate, polyester, polyamide-imide, polyimide, polyetherimide, polyimide having a phenyltrimethylindan structure, polysulfone, polyethersulfone, polyetherketone, polyetheretherketone, polyaramid, polyethernitrile, polybenzimidazole, or a combination thereof. In some embodiments, at least one polymer may include polyaryletherketone (PAEK), polyphenylene sulfide (PPS), polyethersulfone (PES or PESU), polyethyleneimine (PEI), polysulfone (PSU), or a combination thereof. In some embodiments, at least one polymer may include poly-ether-ketone (PEK), polyether-ether-ketone (PEEK), poly-ether-ether-ketone-ketone (PEEKK), poly-ether-ether-ketone-ketone (PEKK), poly-ether-ketone-ether-ketone-ketone (PEKEKK), poly-ether-ether-ketone-ether-ketone (PEEKEK), poly-ether-ether-ether-ketone (PEEEK), and poly-ether-diphenyl-ether-ketone (PEDEK), polyaryletherketone (PAEK)-based polymer materials having reactive (terminal) groups, or a combination thereof.In some embodiments, the PAEK polymer may include various variants commonly referred to as low melting temperature polyaryl ether ketones (LMPAEK™), which have lower melting temperatures and faster processing compared to other PAEK polymers such as PEEK and PEKK, but may possess comparable mechanical properties. Accordingly, in some embodiments, the unidirectional fiber layer may contain a first polymer, and the discontinuous coating layer may contain the same polymer or a different polymer. In some embodiments, the polymer (or polymer resin) impregnating the fiber layer may be the same polymer (or polymer resin) used to form the discontinuous coating layer on the unidirectional fiber layer substrate. 【0016】 In some embodiments, a plurality of (polymer) particles may be applied to the surface of a unidirectional fiber layer as a dry powder or liquid. In some embodiments, discontinuous coating of at least one side / surface of a unidirectional fiber layer with a plurality of (polymer) particles may include melt sputter coating, plasma spraying, and / or electrostatic deposition of the plurality of particles onto at least one side / surface of the unidirectional fiber layer. In some embodiments, deposition may be carried out by an applicator 105, as shown in Figures 1A-B. In some embodiments, the plurality of (polymer) particles used in the discontinuous coating layer may have a volume distribution mean diameter of at least about 5 microns, at least about 10 microns, at least about 20 microns, at least about 40 microns, at least about 60 microns, at least about 65 microns, at least about 70 microns, at least about 75 microns, at least about 100 microns, at least about 125 microns, at least about 135 microns, at least about 150 microns, at least about 175 microns, or at least about 200 microns. In some embodiments, the plurality of (polymer) particles used in the discontinuous coating layer may have a volume distribution mean diameter of at most about 500 microns, at most about 475 microns, at most about 450 microns, at most about 425 microns, at most about 400 microns, at most about 350 microns, at most about 325 microns, at most about 300 microns, at most about 250 microns, at most about 225 microns, at most about 200 microns, at most about 175 microns, at most about 150 microns, or at most about 125 microns. In some embodiments, the multiple (polymer) particles used for the discontinuous coating layer may have a volume distribution mean diameter of approximately 5–500 microns, approximately 20–500 microns, approximately 35–400 microns, and approximately 50–300 microns. In some embodiments, if the volume distribution mean diameter of the multiple (polymer) particles used for the discontinuous coating layer is too small, a sand-like discontinuous coating surface may not be achieved, and / or the particle flow may be non-uniform. In some embodiments, the volume distribution mean diameter can be measured by a conventional laser diffraction particle size analyzer, and the mean particle size is reported as mean volume or D50 value. 【0017】 In some embodiments, the discontinuous coating layer may contain additives. As described above, at least one polymer of the discontinuous coating layer may be a pure resin, or at least one polymer of the discontinuous coating layer may be mixed with additives. In some embodiments, at least one polymer resin (which may contain additives) of the discontinuous layer may have the same or a different composition as at least one polymer resin used to form the unidirectional fiber layer. In some embodiments, the additives of the discontinuous coating layer may improve the performance of a compacted laminate formed using, for example, the unidirectional tape disclosed herein. In some embodiments, the additives may be a combination of conductive, dielectric, non-conductive, and / or other types of additives. In some embodiments, the additives may impart properties other than conductivity or properties combined with conductivity. In some embodiments, the additives may be added to impart insulating, thermal, chemical, and / or mechanical properties. For example, the additives may be added to impart strength, toughness, thermal stability, CTE, and / or resistance to environmental degradation. In some embodiments, the additives may be conductive additives to improve the conductivity of the unidirectional tape. For example, conductive additives may include carbon particles, carbon black, graphene, carbon nanotubes (CNTs), milled carbon fibers, milled carbon fiber prepregs, or combinations thereof. 【0018】 Figure 2 is a cross-sectional view of a unidirectional tape 100, which is an example having a unidirectional fiber layer 101 and a discontinuous coating layer 102 including a discontinuous coating region 103, the discontinuous coating region containing an additive 106 dispersed within its polymer. In some embodiments, the additive may have a volume distribution mean diameter of at least about 5 microns, at least about 10 microns, at least about 15 microns, at least about 20 microns, at least about 25 microns, at least about 30 microns, or at least about 35 microns. In some embodiments, the additive may have a volume distribution mean diameter of at most about 100 microns, at most about 75 microns, at most about 60 microns, at most about 65 microns, at most about 50 microns, at most about 45 microns, at most about 40 microns, at most about 35 microns, at most about 30 microns, or at most about 25 microns. In some embodiments, the additive may have a volume distribution mean diameter of about 5 to 100 microns, about 10 to 50 microns, or about 20 to 40 microns. In some embodiments, if the average volume distribution diameter of the additive is less than 5 microns or greater than 100 microns, the overall conductivity and / or ply-price slip of the UD tape may decrease. In some embodiments, the additive may be mixed or blended with a plurality of (at least one polymer) particles before coating the surface of the unidirectional fiber layer. In some embodiments, the conductive additive is carbon particles. In some embodiments, the carbon particles may be spherical carbon particles. In some embodiments, the additive can be well dispersed in the discontinuous coating layer. In some embodiments, the additive can be well dispersed in the polymer of the discontinuous coating layer. In some embodiments, the amount (or concentration) of the additive may depend on how well the additive is dispersed in the discontinuous coating layer. In some embodiments, the discontinuous coating layer may contain at least about 1 mass%, at least about 2 mass%, at least about 5 mass%, at least about 8 mass%, at least about 10 mass%, at least about 12 mass%, at least about 15 mass%, or at least about 18 mass% of the additive (e.g., conductive, dielectric, and / or other additives). In some embodiments, the discontinuous coating layer may contain at most about 25 mass%, at most about 20 mass%, at most about 18 mass%, at most about 15 mass%, at most about 12 mass%, at most about 10 mass%, at most about 8 mass%, or at most about 5 mass% of the additive (e.g., conductive, dielectric, and / or other additives). In some embodiments, the discontinuous coating layer may contain less than 20% by mass or about 2 to 10% by mass of additives (e.g., conductive, dielectric, and / or other additives). In some embodiments, if the amount of additives in the discontinuous coating layer is less than 2% by mass, the overall conductivity and / or ply-price slip of the UD tape may be reduced. 【0019】 In some embodiments, after discontinuously coating at least one surface / side of the unidirectional fiber layer with a plurality of (polymer) particles (regardless of the presence or absence of additives), the plurality of particles can be heated to integrate on at least one surface / side of the unidirectional fiber layer to form a plurality of discontinuous regions. In other words, the plurality of (polymer) particles discontinuously coated on the surface of the unidirectional fiber layer can be heated above the melting temperature to integrate on at least one surface / side of the unidirectional fiber layer to form a plurality of discontinuous regions. In some embodiments, the plurality of discontinuous regions can form a plurality of discontinuous coating regions on the surface of the unidirectional fiber layer. In some embodiments, these plurality of discontinuous regions can be regions separated by gaps of the coating material on the surface of the unidirectional fiber layer. The plurality of discontinuous coating regions can be arranged on the unidirectional fiber layer so as not to contact other regions of the plurality of discontinuous regions. In some embodiments, the plurality of (polymer) particles can integrate to form separated coating regions (i.e., islands) on the surface of the unidirectional fiber layer (i.e., the sea), forming a "sea-island" morphology. In some embodiments, the plurality of discontinuous regions on at least one surface / side of the unidirectional fiber layer can be cooled after heating. In some embodiments, the coated unidirectional fiber layer can be cooled. In some embodiments, the entire unidirectional tape can be cooled. 【0020】 In some embodiments, the average surface area (i.e., size) of the plurality of discontinuous coating regions on at least one side of the unidirectional fiber layer (the average surface area of the discontinuous coating regions) is at least about 500 microns 2 , at least about 1000 microns 2 , at least about 2000 microns 2 , at least about 2500 microns 2 , at least about 3000 microns 2 , at least about 3500 microns 2 , at least about 4000 microns 2 , at least about 5000 microns 2 or at least about 7500 microns 2This is possible. In some embodiments, the average surface area of ​​multiple discontinuous coating regions on at least one side of the unidirectional fiber layer is at most about 300,000 microns. 2 At most, approximately 200,000 microns 2 At most, approximately 100,000 microns 2 At most, approximately 50,000 microns 2 at most 20,000 microns 2 At most, approximately 15,000 microns 2 At most, about 10,000 microns 2 At most, approximately 8000 microns 2 At most, approximately 7500 microns 2 At most, about 6000 microns 2 At most, about 5000 microns 2 At most, approximately 4500 microns 2 At most, about 4000 microns 2 At most, approximately 3500 microns 2 At most, about 3000 microns 2 At most, approximately 2500 microns 2 Or at most about 2000 microns 2 It is possible. In some embodiments, at most about 99%, at most about 90%, at most about 85%, at most about 75%, at most about 70%, at most about 65%, at most about 60%, at most about 55%, or at most about 50% of a plurality of discontinuous coating regions on at least one side of a unidirectional fiber layer are at least about 200 microns. 2 Or at least about 500 microns 2 It may have a surface area of ​​. In some embodiments, at least about 45%, at least about 50%, at least about 55%, or at least about 60% of a plurality of discontinuous coating regions on at least one side of the unidirectional fiber layer is at least about 200 microns. 2 Or at least about 500 microns 2 It may have a surface area of 【0021】 In some embodiments, a unidirectional tape can be formed by pressurizing at least one side of a coated unidirectional fiber layer. In some embodiments, a unidirectional tape can be formed by pressurizing both sides of a coated unidirectional fiber layer. In other words, a unidirectional tape can be formed by compressing a coated unidirectional fiber layer. In some embodiments, the coated unidirectional fiber layer can be cooled under compression. In some embodiments, pressurization (or compression) can be performed with a compression roller. In some embodiments, the pressurization / compression on at least one side of the coated unidirectional fiber layer may be at a pressure of about 0.1–10 N / mm, about 0.1–2 N / mm, about 2–5 N / mm, or about 5–10 N / mm. In some embodiments, the pressure applied to at least one side of the coated unidirectional fiber layer may be at least about 0.1 N / mm, at least about 0.5 N / mm, at least about 1 N / mm, at least about 1.5 N / mm, at least about 2 N / mm, at least about 3 N / mm, at least about 4 N / mm, at least about 5 N / mm, at least about 6 N / mm, at least about 7 N / mm, at least about 8 N / mm, or at least about 9 N / mm. In some embodiments, the pressure applied to at least one side of the coated unidirectional fiber layer may be at most about 10 N / mm, at most about 5 N / mm, at most about 4 N / mm, at most about 3 N / mm, at most about 2 N / mm, at most about 1.5 N / mm, or at most about 1 N / mm. In some embodiments, the pressure applied to the tape may be calculated by dividing the total compressive force on the tape by the tape width. In some embodiments, the discontinuous coating layer covers at least a portion of the surface of at least one side / surface of the unidirectional fiber layer. In other words, at least a portion of the surface of the unidirectional fiber layer is covered by multiple discontinuous coating regions. In some embodiments, the discontinuous coating layer covers at least about 5%, at least about 10%, at least about 15%, at least about 20%, at least about 25%, at least about 27%, at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, or at least about 70% of the surface area of ​​at least one side / surface of the unidirectional fiber layer. In some embodiments, the discontinuous coating layer covers at most about 85%, at most about 80%, at most about 75%, at most about 65%, at most about 55%, at most about 50%, at most about 45%, at most about 40%, at most about 35%, at most about 30%, at most about 25%, or at most about 20% of the surface area of ​​at least one side / surface of the unidirectional fiber layer. In some embodiments, the discontinuous coating layer covers about 5–75%, about 10–75%, about 15–75%, about 20–75%, about 10–50%, about 20–40%, or about 27–35% of the surface area of ​​at least one side / surface of the unidirectional fiber layer. For example, 5–75% of the surface area of ​​one side / surface of the unidirectional fiber layer can be covered by the discontinuous coating layer (i.e., multiple discontinuous coating regions) ("islands"), with the remaining surface being the uncoated unidirectional fiber layer. In some embodiments, the surface coverage of the discontinuous coating layer can be quantified by microscopy (e.g., scanning electron microscopy). 【0022】 In some embodiments, the discontinuous coating layer may impart a specific roughness or "sandy" texture / surface to the UD tape. The roughness of the UD tape can be measured by calculating the coefficient of variation of the thickness of the UD tape. In some embodiments, the coefficient of variation (CoV) of the thickness of the UD tape may be at least about 2%, at least about 5%, at least about 6%, at least about 7%, at least about 8%, at least about 9%, at least about 10%, at least about 12%, at least about 15%, at least about 20%, or at least about 25%. In some embodiments, the CoV of the thickness of the UD tape may be at most about 50%, at most about 40%, at most about 35%, at most about 30%, at most about 25%, at most about 20%, at most about 15%, at most about 12%, or at most about 10%. In some embodiments, the average height or thickness of multiple discontinuous coating regions is approximately 5 to 150 microns. The average height or thickness of multiple discontinuous coating regions can be calculated by measuring the heights of 10 randomly selected discontinuous coating regions using cross-sectional microscopy and averaging these measurements. During the manufacture of UD tape, voids may occur between the base unidirectional fiber layer and the discontinuous coating layer within the range of the unidirectional fiber layer and / or discontinuous coating layer. However, by partially or discontinuously coating the surface of the unidirectional layer, the voids can be reduced compared to continuous coating of the surface of the unidirectional layer, while still maintaining / preserving surface roughness. In some embodiments, the maximum void ratio of the unidirectional tape may be at most about 10%, at most about 8%, at most about 6%, at most about 5%, at most about 2%, at most about 1%, or at most about 0.9%. In some embodiments, the maximum void ratio of the unidirectional tape may be at least about 0.01%, at least about 0.1%, at least about 0.25%, at least about 0.5%, at least about 0.6%, at least about 0.7%, at least about 0.8%, at least about 0.9%, or at least about 1%. In some embodiments, the maximum void ratio of the unidirectional tape may be about 0.01–6%. 【0023】 As described above, discontinuous coating layers can achieve multiple functions, including achieving multiple functions simultaneously. In some embodiments, discontinuous coating layers can reduce ply-mold slip or friction and / or ply-ply slip or friction. For example, by discontinuously coating the surface of a unidirectional fiber layer with an additional polymer, friction between adjacent plies (i.e., ply-ply friction) can be reduced and / or optimized for lateral movement between adjacent plies during the melting stage of laminate consolidation. In other words, the polymer of the discontinuous coating layer can act as a sliding surface for lateral movement between plies. The reduction in friction between plies and / or between tools and composite stacks can improve moldability in various processes (stamping, thermoforming, etc.), especially in tight bending and / or consolidation of complex shapes. Thus, improved moldability can reduce ply buckling and / or waviness, enabling high-speed molding and molding of complex shapes. Furthermore, the reduction / optimization of ply-ply friction can reduce wrinkles and other defects in the consolidated portion. In some embodiments, the ply-ply friction of the unidirectional tapes disclosed herein can be reduced by at least 10%, at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, or at least 70% compared to the use of standard UD tapes without any coating layer. In some embodiments, the peak stress of the unidirectional tapes disclosed herein can be reduced by at least 10%, at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, or at least 70% compared to standard UD tapes without any coating layer. In some embodiments, the unidirectional tapes disclosed herein have ply-ply slip, and the laminated surface of the test part is wrinkle-free. Test parts can be made by stamping identification parts with a sufficient bending radius, and the difference in ply-ply slip between different thermoplastic UD tapes can be determined. Sufficient ply-ply slip can form parts that do not have tactile (out-of-plane) wrinkles on the part surface. Insufficient ply-ply slip can form parts that have tactile wrinkles on the part surface. 【0024】 In some embodiments, discontinuous coating layers can improve and / or maintain degassing efficiency by preserving interply channels. By discontinuously or partially coating the surface of the unidirectional fiber layer (rather than adding a continuous coating layer), voids or channels can be preserved between the first ply and the mold, and / or between subsequent plies in the stack. This can promote degassing efficiency in various lamination processes such as OOA and / or vacuum bag only (VBO), while the ply stack remains below the melting temperature of the polymer in the coating. The degassing effect can produce laminates with low porosity and / or improved productivity. Discontinuous coating layers can preserve interply channels between the first ply and the mold, and / or between subsequent plies, for degassing (e.g., in OOA or VBO consolidation). These voids / channels may be continuous channels that can remove gases (e.g., air, moisture, and / or any residual volatile components) during the degassing / debulking process (of the OOA or VBO process), while the ply stack is still below the melting temperature of the polymer in the UD tape. In the subsequent consolidation process, for example, when a completely degassed ply stack is heated above the melting temperature of the polymer and the stack is consolidated (and cooled) under pressure, the voids may be closed without trapping gases (e.g., air, moisture, and / or any volatile components) within the consolidated UD tape. In some embodiments, discontinuous coating layers can improve and / or maintain interply conductivity and / or thermal conductivity (e.g., Z-direction conductivity). The discontinuous coating layers disclosed herein are formed on the surface of a base unidirectional fiber layer and thus can separate adjacent plies in the next laminate, avoiding the formation of a continuous layer of insulating polymer that would cause a reduction in interply electrical and / or thermal conductivity. Improving and / or maintaining interply conductivity can accelerate processing speed in various lamination processes such as induction heating and induction welding. However, even when induction heating or induction welding is not used, this feature can improve processability by improving thermal conductivity. Furthermore, improving and / or maintaining interply conductivity can help protect the next laminate from damage in areas with a risk of lightning strikes. 【0025】 As described above, the electrical (Z-direction) conductivity between plies of the resulting laminate can be improved by adding additives to the discontinuous coating layer. For example, the conductive pathways between adjacent plies can be improved by preparing (e.g., mixing) polymer particles to be added to the surface of a unidirectional fiber layer in a sufficient amount / concentration of additive (e.g., carbon particles) to exceed the conductivity penetration threshold of the coating layer. In some embodiments, discontinuous coating layers characterized by specific area coverage and / or surface roughness disclosed herein can reduce ply-ply friction while maintaining sufficient electrical and / or thermal conductivity between adjacent plies. While continuous coating layers can reduce ply-ply friction, they form electrical and thermal insulating layers, which can be detrimental to lamination processes such as induction heating and induction welding. Conversely, without coating, tack weld strength may be too low and ply-ply friction too high, which can lead to surface wrinkling in the laminate and negatively impact part formability and quality. 【0026】 In some embodiments, the discontinuous coating layer of the UD tape disclosed herein can improve the adhesion of the first ply to the mold and / or to the next ply. During layup, when close to the melting temperature of the ply stack, the polymer of the discontinuous coating layer can locally improve the adhesion of the first ply to the mold and / or to the next ply compared to a unidirectional fiber base without a coating. This can be beneficial for precise ply alignment in AFP and / or ATP processes. In some embodiments, the unidirectional tape disclosed herein can have an adhesion measured by average or maximum weld strength (lap shear strength measured after thermal welding), which is at least about 100 lb / in, at least about 250 lb / in, at least about 500 lb / in, at least about 750 lb / in, at least about 800 lb / in, at least about 850 lb / in, at least about 900 lb / in, or at least about 1000 lb / in. In some embodiments, the unidirectional tapes disclosed herein may have tackiness measured by average or maximum weld strength (lap shear strength measured after heat welding), which is at most about 5000 lb / in, at most about 2500 lb / in, or at most about 1000 lb / in. In some embodiments, tackiness may be measured by measuring the strength of the weld formed after joining two 2.54 cm (1 inch) × 15.24 cm (6 inch) plies of joined unidirectional tapes with a 2.54 cm (1 inch) overlap using a conventional soldering iron. Using a universal tester, the welded plies were pulled with a tensile force perpendicular to the weld in tensile mode. In some embodiments, the tackiness of the unidirectional tapes disclosed herein (for ply-ply & ply-mold alignment) can be improved by at least 10%, at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, or at least 75% compared to the use of standard UD tapes without any coating layer. In some embodiments, the improved surface roughness of the UD tape due to the discontinuous coating layer can enhance the processability of the UD tape, providing part manufacturers with flexibility in selecting layup and compaction processes. This can be particularly accurate in ultrasonic tape placement and lamination, as well as laser AFP. 【0027】 Examples Eight UD tapes and base tapes were fabricated, and their top and cross-sectional views were analyzed. The base tapes were made from a unidirectional fiberbed of carbon fiber tow and then impregnated with PAEK polymer. The base tapes had no further coatings. Figures 3A-B show a 200x magnification top view and a 500x magnification cross-section representative of this uncoated UD tape (i.e., base tape). Thin-coated UD tapes were fabricated on a unidirectional fiber bed of carbon fiber tow and subsequently impregnated with PAEK polymer. Then, a "thin" discontinuous coating layer of PAEK polymer was applied to both sides of the unidirectional fiber layer. Figures 4A-B show representative top and 500x magnification cross-sectional views of this thin-coated UD tape. The surface coverage of the unidirectional fiber layer by this discontinuous coating layer varied from 11% to 48% depending on the compression pressure, as shown in the table below, with a coefficient of variation ranging from 5% to 7%. An intermediate coating UD tape was fabricated on a unidirectional fiber bed of carbon fiber tow, and subsequently impregnated with PAEK polymer. Then, an "intermediate" discontinuous coating layer of PAEK polymer was applied to both sides of the unidirectional fiber layer. The surface coverage of the unidirectional fiber layer by this discontinuous coating layer varied from 6% to 79% depending on the compression pressure, as shown in the table below, and the CoV ranged from 8% to 12%. Figures 5A and 5B are top views at 200x magnification and cross-sectional views at 500x magnification of this intermediate coating UD tape. Thickly coated UD tapes were fabricated on a unidirectional fiber bed of carbon fiber tow and subsequently impregnated with PAEK polymer. Then, a "thick" discontinuous coating layer of PAEK polymer was applied to both sides of the unidirectional fiber layer. The surface coverage of the unidirectional fiber layer by this discontinuous coating layer varied from 46% to 83% depending on the compression pressure, as shown in the table below, with a CoV of 9%. Figures 6A-B are top views at 200x magnification and cross-sectional views at 500x magnification of this thickly coated UD tape. 【0028】 The applicant prepared the following examples in comparison to a standard UD tape without a coating. The specific configurations and characteristics of the examples and comparative examples are shown in Tables 1 and 2 below. [Table 1] [Table 2] 【0029】 As shown in the table above, tack weld strength can improve with increasing coverage. Ply-ply slip correlates with coverage. In other words, an improvement in ply-ply slip is equal to a decrease in peak stress with increasing coverage. 【0030】 Calculation of surface area coverage ratio of discontinuous coating layer in unidirectional fiber layer An example of a method for calculating the surface area coverage of a discontinuous coating layer in a unidirectional fiber layer is as follows: For each sample of UD tape, 10 1.27 × 1.27 cm (0.5 × 0.5 inch) samples were cut from the UD tape sample at five locations along the tape width. Five samples each from the top and bottom surfaces were imaged using a scanning electron microscope (SEM). The samples were sputter-coated with 5 nm gold to improve image quality. Each sample was imaged at 200x using a PhenomXL scanning electron microscope to produce 1.3 mm × 1.3 mm images. The surface resin was manually identified and marked, and then the images were posterized to increase contrast. The percentage of resin coverage was determined using the number of pixels. Calculation of conductivity in the Z direction To calculate the Z-direction conductivity of the UD tape, a 30.48 cm (12 inch) × 40.64 cm (16 inch) × 10-ply pseudo-isotropic laminate of each UD tape was compacted at 3.5 bar, 365° press, according to standard industry practice. From each panel, smaller 40 mm × 40 mm test specimens were cut, polished, and coated with conductive silver paste. The resistance was measured using the four-probe method, and the corresponding Z-direction conductivity was calculated as conductivity = t / (R × L * W), where t = thickness, R = resistance, L = length, and W = width. In some embodiments, the unidirectional tape has a Z-direction conductivity of at least about 0.01 S / m, at least about 0.02 S / m, at least about 0.03 S / m, at least about 0.04 S / m, at least about 0.05 S / m, at least about 0.06 S / m, at least about 0.07 S / m, at least about 0.08 S / m, at least about 0.09 S / m, or at least about 0.1 S / m. In some embodiments, the unidirectional tape has a Z-direction conductivity of at most about 1.5 S / m, at most about 1.25 S / m, at most about 1 S / m, at most about 0.09 S / m, at most about 0.08 S / m, at most about 0.07 S / m, at most about 0.06 S / m, or at most about 0.05 S / m. 【0031】 Calculation of roughness, degassing efficiency, and void ratio of UD tape An example of a method for calculating the CoV (Coefficient of Variation) of UD tape is as follows: First, a sample is prepared to measure surface roughness. The UD tape sample is cut and mounted perpendicularly to epoxy resin for potting and polishing. After sanding the sample to 1200 grit, it is polished with a 0.3 micron pad. It is imaged at 200x using a Keyence VHX-6000 optical microscope. Then, using standard microscopy techniques, a microscopic image of the UD tape with fibers facing the polished surface is taken. For a typical sample size, an image at least 15 mm wide is taken. Figure 7A shows enlarged and reduced portions of the 15 mm wide image. Next, black and white thresholding is used to distinguish the epoxy potting from the UD tape. As shown in Figure 7B, the polymer of the UD tape (shown in white) has a different color from the potting resin (shown in black). Then, the thickness of the UD tape is measured every 1 to 5 microns to calculate the thickness distribution. From this, the standard deviation, mean, and coefficient of variation (CoV) can be calculated. The roughness of UD tape is the coefficient of variation of the thickness of the UD tape. In some embodiments, the statistical distribution of thickness is bimodal or multimodal, with the primary mode representing the thickness of the base tape and the other mode varying by 25% (±15%) of the base tape thickness (created by discontinuous resin coating regions on the surface). In some embodiments, the distribution can generally be broader than that of a classic composite tape with a CoV of approximately 12% (±4%). In some embodiments, the PDE of the thickness distribution is obtained by counting all measured thicknesses and their frequencies (n>10000) (see Figure 7B). To quantify the degassing efficiency of UD tape, the porosity of thick laminates made from UD tape was measured. Following standard industry practice, 30.48 cm (12 inch) × 30.48 cm (12 inch) × 40-ply cross-ply laminates of each UD tape were compacted by vacuum bagging. Subsequently, the porosity was measured for each laminate according to the industry standard ASTM method for acid digestion and density measurement. Since higher degassing efficiency results in lower porosity of the laminate formed by compacting individual plies of UD tape, degassing efficiency can be measured in terms of porosity. 【0032】 Price-Price Slip Calculation The resistance to sliding between adjacent plies was measured using a ply-ply friction test apparatus. A detailed description of the test apparatus and general test method is obtained from Composites:PartA 179(2024)108040, which is incorporated herein by reference in its entirety. For these specific tests, the specimen consisted of three 50 mm wide plies cut from a sample of UD tape: one 150 mm long central ply and two 120 mm long outer plies with longitudinally oriented fibers. The three plies overlapped by more than 60 mm in length, resulting in two ply-ply interfaces. These plies were in contact area A of 50 × 50 mm. 2 Pressurization was applied between heated platens. The temperature was set to 365°C and a standard pressure of 15 kPa was applied. A constant sliding rate of 25 mm / min was applied, and the center ply was slid against the outer ply. Required tensile force F pull The displacement d and time t were recorded. The shear stress per slip interface is τ = F pull Obtained from / 2A. In some embodiments, the ply-ply slip stress of the unidirectional tapes disclosed herein may be at least about 15 ksi, at least about 20 ksi, at least about 25 ksi, at least about 30 ksi, at least about 35 ksi, at least about 40 ksi, at least about 45 ksi, at least about 50 ksi, or at least about 55 ksi. In some embodiments, the ply-ply slip stress of the unidirectional tapes disclosed herein may be at most about 80 ksi, at most about 75 ksi, at most about 70 ksi, at most about 65 ksi, at most about 60 ksi, at most about 55 ksi, at most about 50 ksi, at most about 45 ksi, at most about 40 ksi, at most about 35 ksi, at most about 30 ksi, or at most about 25 ksi. 【0033】 This application discloses several numerical ranges in the text and drawings. Since this disclosure can be implemented throughout the entire disclosed numerical range, the exact limits of the range are not verbatim stated in the specification; however, the disclosed numerical range essentially supports any range or value within the disclosed numerical range, including the endpoint. 【0034】 The above description is presented so that a person skilled in the art can make and use this disclosure, and is shown in terms of a particular use and its requirements. Various modifications to preferred embodiments will be readily apparent to a person skilled in the art. The general principles defined herein may be applied to other embodiments and uses without departing from the spirit and scope of this disclosure. Accordingly, this disclosure is not intended to limit itself to the embodiments shown, but should be consistent with the broadest scope that does not contradict the principles and features disclosed herein. Finally, all disclosures of patents and publications referenced herein are incorporated herein by reference.

Claims

[Claim 1] A unidirectional fiber layer comprising multiple unidirectional fibers and a first polymer; The discontinuous coating layer includes a plurality of discontinuous coating regions on at least one side of the unidirectional fiber layer, and comprises a second polymer. One-way tape, including [Claim 2] The unidirectional tape according to claim 1, wherein the discontinuous coating layer covers 5 to 75% of the surface area of ​​at least one side of the unidirectional fiber layer. [Claim 3] The unidirectional tape according to claim 1 or 2, wherein the thickness of the unidirectional tape has a coefficient of variation (CoV) of 5 to 50%. [Claim 4] The unidirectional tape according to any one of claims 1 to 3, wherein the first polymer and / or second polymer comprises a polyaryl ether ketone polymer material, polyphenylene sulfide (PPS), polyethersulfone (PES or PESU), polyethyleneimine (PEI), or a combination thereof. [Claim 5] The unidirectional tape according to any one of claims 1 to 4, wherein the first and second polymers are the same. [Claim 6] The unidirectional tape according to any one of claims 1 to 5, wherein the plurality of unidirectional fibers include carbon fibers, glass fibers, or a combination thereof. [Claim 7] The unidirectional tape according to any one of claims 1 to 6, wherein the discontinuous coating layer contains a conductive additive. [Claim 8] The unidirectional tape according to claim 7, wherein the conductive additive contains carbon particles. [Claim 9] The unidirectional tape according to claim 8, wherein the carbon particles have a volume distribution average diameter of 10 to 50 microns. [Claim 10] The unidirectional tape according to claim 8, wherein the discontinuous coating layer contains 2 to 10% by mass of carbon particles. [Claim 11] The unidirectional tape according to any one of claims 1 to 10, wherein the unidirectional fiber layer contains a conductive additive. [Claim 12] The unidirectional tape according to claim 11, wherein the conductive additive includes carbon black, graphene, carbon nanotubes (CNTs), milled carbon fibers, milled carbon fiber prepregs, or a combination thereof. [Claim 13] The unidirectional tape according to claim 11, wherein the conductive additive has a volume distribution average diameter of 20 nanometers to 1 micron. [Claim 14] The unidirectional tape according to claim 11, wherein the unidirectional fiber layer contains 0.1 to 10% by mass of a conductive additive. [Claim 15] A step of preparing a unidirectional fiber layer containing multiple unidirectional fibers and a first polymer; A step of discontinuously coating at least one side of the unidirectional fiber layer with a plurality of particles containing a second polymer; A step of heating the plurality of particles so that they become integrated on at least one side of the unidirectional fiber layer to form a plurality of discontinuous regions; A step of forming a unidirectional tape by applying pressure to at least one side of the coated unidirectional fiber layer, A method for manufacturing a one-way tape, including the method described above. [Claim 16] The method according to claim 15, wherein the plurality of particles have an average particle diameter of 5 to 500 microns.

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