Thin braided jacket

Abstract

A method for producing a core-sheath structure by shaping at least one filament bundle including a plurality of filaments to form at least one shaped-filament strand, and braiding a plurality of strands including the at least one shaped-filament strand to form a core-sheath structure including a braided sheath of strands over and surrounding a core, wherein the shaped-filament strand is a no-twist strand having a twist level of less than 1 turn per meter, the shaped-filament strand has a cross-sectional aspect ratio of at least 3:1 as measured at the braided sheath, at least a portion of the braided sheath has a thickness in the range of about 10 to about 200 pm, and the braided sheath includes synthetic fibers having a tensile strength greater than 12 cN / dtex. Also disclosed herein are core-sheath structures formed by such a method.

Description

[Technical Field]

[0001] This application relates generally to materials technology, and more specifically to the manufacture of braided core-sheath structures with improved surface properties. More specifically, this application discloses core-sheath structures having a central core at least partially surrounded by a braided jacket (sheath) of low thickness and high strength. The core-sheath structures disclosed herein include cords that are useful, for example, as tensile structures in medical applications. [Background technology]

[0002] Braided cords having a central core surrounded by a braided jacket (sheath) have been known for some time and are used in a wide variety of applications. These braided materials, often described as "core-sheath" constructions, are useful in applications such as fishing line, netting, blind cordage, rope, and medical fabrics.

[0003] In contrast to core-sheath constructions, cords that do not include a braided jacket are more susceptible to loss of integrity due to untwisting and are more susceptible to damage to the load-bearing fibers due to abrasion, cutting, or strand pull-out.

[0004] In certain applications, such as surgical cords, the properties of the braided jacket can greatly affect the functionality and usefulness of a cord having a core-sheath structure. For example, because conventional sheath structures are typically formed by braiding twisted strands that are resistant to flattening, conventional braided jackets tend to be stiff, thick structures that behave differently than the underlying core structure.

[0005] In compact core-sheath cords for specialized applications, such as medical cords, where the volume available for cord passage is limited, the thickness of the protective jacket can be a limiting factor. The ability to selectively flatten the strands of the protective jacket (sheath) can minimize the volume occupied by the jacket, thereby allowing the use of a larger core structure (braid or twist) to increase load-bearing capacity within the same volume. The ability to selectively flatten the strands of the protective jacket may allow the diameter of the core-sheath cord to be reduced while maintaining the load-bearing capacity of conventional core-sheath cords with larger diameters.

[0006] The use of a flattened jacket in a core-sheath construction may also allow the sheath to better conform to the cross-sectional shape of the core, particularly in applications where the cross-sectional shape of the core-sheath cord is preferably controlled to allow for better maneuverability of the cord during use. The ability to control the shape of the jacket in a core-sheath construction may allow the surface texturing of the core-sheath structure to be tailored to specific applications where surface texture and / or roughness is a factor. Summary of the Invention [Problem to be solved by the invention]

[0007] The present inventors have recognized a need to discover methods and materials for manufacturing core-sheath structures with thin braided sheaths that exhibit greater flexibility and control compared to conventional sheath structures. For example, a need exists for manufacturing core-sheath cords in which the braided sheath is in the form of a low-profile jacket that dynamically conforms to the outer surface of an underlying central core while protecting the cord from damage. There is also a need for manufacturing core-sheath structures in which the texture of the braided jacket can be controlled to increase or decrease surface roughness compared to conventional jackets, which can be used to impart improved properties to medical textiles and other cord-like structures. [Means for solving the problem]

[0008] The following disclosure describes the manufacture and utility of a core-sheath structure having a selectively flattened braided sheath that can dynamically conform to the outer surface of the core while simultaneously serving to protect the core.

[0009] Embodiments of the present disclosure are described herein to enable one of ordinary skill in the art to make and use them, and include: (1) One aspect relates to a method for manufacturing a cord having a core-sheath structure by shaping at least one filament bundle including a plurality of filaments to form at least one filament-shaped strand, and then braiding a plurality of strands including the at least one filament-shaped strand to form a core-sheath structure including a core over which a braided sheath of strands surrounds the core. In some embodiments, (a) the filament-shaped strand is a no-twist strand having a twist level of less than 1 turn per meter, (b) the cross-sectional aspect ratio of the filament-shaped strand is at least 3:1 as measured at the braided sheath, (c) at least a portion of the braided sheath has a thickness in the range of about 10 to about 200 μm, and / or (d) the braided sheath includes synthetic fibers having a tensile strength greater than 12 cN / dtex; and (2) Another aspect relates to a cord having a core-sheath structure including a core and a braided sheath of strands surrounding the core, the braided sheath including strands having a braid angle of 5° or greater in a relaxed state, wherein the strands having a braid angle of 5° or greater in a relaxed state include at least one shaped filament strand. In some embodiments, (a) the shaped filament strand is a no-twist strand having a twist level of less than 1 turn per meter, (b) the shaped filament strand has a cross-sectional aspect ratio of at least 3:1 as measured at the braided sheath, (c) at least a portion of the braided sheath has a thickness of about 20 to about 200 μm, and / or (d) the braided sheath includes synthetic fibers having a tensile strength of greater than 12 cN / dtex.

[0010] Additional objects, advantages, and other features of the present disclosure are set forth in part below, and in part will become apparent to those skilled in the art upon examination of the following or may be learned from the practice of the present disclosure. The present disclosure encompasses embodiments other than those described in detail below, as well as different embodiments, and the details herein can be modified in various respects without departing from the present disclosure. In this regard, the description herein is to be understood as illustrative in nature and not as restrictive.

[0011] Embodiments of the present disclosure are explained in the following description with reference to the figures in which: [Brief explanation of the drawings]

[0012] [Figure 1] Figure 1 shows a cross section of a core-sheath structure with a central core partially surrounded by a biaxially braided jacket (sheath) formed from strands braided in the left (Z) and right (S) directions; [Figure 2] FIG. 2 shows a cross section of a conventional core-sheath construction having a central core surrounded by a braided jacket (sheath) formed from twisted Z strands and twisted S strands that are flatten-resistant and form thick bulges where the Z and S strands overlap; [Figure 3] FIG. 3 shows a cross-section of a core-sheath structure of the present disclosure having a central core surrounded by a flat braided jacket (sheath) formed from untwisted Z strands and untwisted S strands shaped to have a cross-sectional aspect ratio of at least 3:1; [Figure 4A] FIG. 4A shows one embodiment of a 12-carrier braiding device capable of producing the core-sheath structure of the present disclosure; [Figure 4B] FIG. 4B shows one embodiment of an improved braided carrier that can be used to manufacture the core-sheath structure of the present disclosure; [Figure 4C] FIG. 4C illustrates one embodiment of a molding apparatus that can be used to manufacture the core-sheath structure of the present disclosure; [Figure 5]FIG. 5 shows the cross-section of an unshaped filament bundle (strand) compared to the shaped strands of the present disclosure having curved and flat cross-sections; [Figure 6] Figure 6 shows the aspect ratio of a filament-shaped strand with a curved cross section; [Figure 7A] Figure 7A shows the surface of a non-optimized braided jacket (sheath) with gaps; [Figure 7B] Figure 7B shows the surface of the optimized braided jacket (sheath) with no gaps and higher surface coverage compared to the non-optimized braided jacket in Figure 7A; [Figure 8] FIG. 8 shows a cross-section of a core-sheath structure of the present disclosure having a triangular central core surrounded by a flat braided jacket (sheath) formed from untwisted Z-strands and untwisted S-strands shaped to have a cross-sectional aspect ratio of at least 3:1; [Figure 9] FIG. 9 shows a cross-section of a core-sheath structure of the present disclosure having a circular central core formed from shaped S-strands having a cross-sectional aspect ratio of at least 3:1 and surrounded by a hybrid braided jacket (sheath) formed from unshaped Z-strands having a cross-sectional aspect ratio of less than 2:1; and [Figure 10] Figure 10 shows a cross section of a core-sheath structure with a central core partially surrounded by a triaxial jacket (sheath) formed from strands braided in the Z and S directions and longitudinal strands with a braid angle of less than 5° in the relaxed state. DETAILED DESCRIPTION OF THE INVENTION

[0013] Embodiments of the present disclosure include various methods for manufacturing core-sheath structures, as well as cords obtained by these methods. Specific, non-limiting uses of the core-sheath structures of the present disclosure are also described herein.

[0014] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the relevant art. In case of conflict, the present specification, including definitions, will control.

[0015] Unless otherwise stated, all percentages, parts, ratios, etc. are by weight.

[0016] When amounts, concentrations, or other values ​​or parameters are described as ranges or lists of upper and lower limits, they should be understood to specifically disclose all ranges formed from any pair of upper and lower range limits, regardless of whether the ranges are individually disclosed. When a range of numerical values ​​is described herein, unless otherwise specified, the range is intended to include its endpoints, and all integers and fractions within the range. It is not intended that the scope of this disclosure be limited to the specific values ​​recited when defining a range.

[0017] The use of "a" or "an" to describe various elements and components herein is merely for convenience and to give a general sense of the disclosure. The description should be understood to include one or at least one, and the singular also includes the plural unless it is clear that otherwise is meant.

[0018] Unless expressly stated to the contrary, "or" and "and / or" are inclusive, not exclusive. For example, condition A or B, or A and / or B, may satisfy any of the following: A is true (or exists) and B is false (or does not exist), A is false (or does not exist) and B is true (or exists), and A and B are both true (or exist).

[0019] As used herein, the terms "about" and "approximately" mean approximately the same as a referenced amount or value and should be understood to encompass ±5% of the specified amount or value.

[0020] As used herein, unless otherwise defined, the term "substantially" means all or nearly all or the majority as would be understood by one of ordinary skill in the art in the context in which it is used. This is intended to allow for some reasonable variation from 100% that typically occurs in industrial or commercial scale situations.

[0021] Throughout this specification, unless otherwise defined and explained, the technical terms and methods used to measure relevant measurements are as described in ASTM D855 / D885M -10A(2014), Standard Test Methods for Tire Cords, Tire Cord Fabrics, and Industrial Filament Yarns Made From Man-made Organic-base Fibers, published October 2014.

[0022] For convenience, many elements of the various embodiments disclosed herein are described separately. Although lists of options may be provided and numerical values ​​may be within ranges, the disclosure should not be considered limited to the separately described lists and ranges. Unless otherwise stated, each and every combination possible within the disclosure should be considered expressly disclosed for all purposes.

[0023] The materials, methods, and examples herein are illustrative only and, unless otherwise specified, are not intended to be limiting. Methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the present disclosure.

[0024] <Core-sheath structure with shape-controlled jacket> Embodiments described herein include methods and materials for manufacturing core-sheath structures with shape-controlled jackets (sheaths) that exhibit improved properties compared to conventional braided sheaths. In some cases, the reduced thickness of the shape-controlled jacket allows the sheath shape to more closely conform to the outer surface of the core in order to control the texturing and surface roughness of the resulting core-sheath structure.

[0025] As used herein, the term "core-sheath structure" refers to a cord-like structure having an outer sheath (jacket) of braided strands at least partially surrounding a central core. Different views and embodiments of such core-sheath structures are shown in Figures 1-3, 7A, 7B, and 8-10.

[0026] FIG. 1 shows the basic configuration of a core-sheath structure 5, which includes a central core 10 partially surrounded in this depiction by a biaxially braided jacket (sheath) 15 formed from S strands 20 braided in a left-hand direction along the braid axis 25 of the core 10 and Z strands 30 braided in a right-hand direction along the braid axis 25.

[0027] As shown in FIG. 1, the surface of the braided jacket (sheath) 15 includes protrusions 35 where the S and Z strands 20 and 30 overlap. The distance (S) 40 between adjacent protrusions 35 along the braid axis 25 of the braided jacket (sheath) 15 is indirectly related to the pick count of the braid. In a braided rope or jacket, "pick count" is defined as the number of strands (i.e., S strands 20 or Z strands 30 in FIG. 1) rotating in one direction over one cycle length, divided by the cycle length. Pick count is typically expressed as the number of crossovers per inch or per meter. Thus, as the distance (S) 40 in FIG. 1 increases, the pick count of the braided jacket (sheath) 15 decreases.

[0028] 1 is only partially surrounded by the braided jacket (sheath) 15, there are also numerous gaps 45 in the braided sheath 15, which exhibits less than 100% surface coverage. In other core-sheath structures, where the braided jacket (sheath) 15 has a surface coverage approaching or exceeding 100%, there are no gaps 45 in the braided sheath 15.

[0029] Also depicted in Figure 1 is a "plane P" 50 that defines a cross-section of the core-sheath structure 5 at a point along the braid axis 25 where there is a protrusion 35 formed by the overlapping S and Z strands 20 and 30. A similar "plane P" 50 is defined as the plane of the paper in Figures 2, 3, 8 and 9.

[0030] As explained above, embodiments of the present disclosure include a core-sheath structure with a shape-controlled (flattened) jacket of reduced thickness that can more closely conform to the outer surface of the core in order to control the texturing and surface roughness of the outer surface of the core-sheath structure. A comparison of Figures 2 and 3 illustrates this feature.

[0031] 2 shows a cross section of a conventional core-sheath structure 5 having a central core 10 surrounded by a biaxial braided jacket (sheath) 15 formed from twisted S-strands and twisted Z-strands 55 and 60 braided along a braid axis (not shown) extending outward in a direction perpendicular to "plane P" 50 of the core 10. As shown in FIG. 2, the sides of the braided jacket (sheath) 15 include protrusions 35 where the S-strands and Z-strands 55 and 60 overlap.

[0032] FIG. 2 also shows the maximum and minimum diameters (D max and D min ) 65 and 70. D max 65 is the maximum diameter measured between the projections 75 and 75′ located on opposite sides of the braided sheath 15, while D min70 is the smallest diameter measured between non-overlapping S or Z strands 80 and 80' located on opposite sides of braided sheath 15.

[0033] Because the braided sheath 15 in the conventional core-sheath structure 5 shown in Figure 2 is formed using stiff, flattening-resistant twisted S-strands and twisted Z-strands, there are large protrusions 35 on the sides of the braided sheath 15 that result in significant texturing and surface roughness of the core-sheath structure 5. In contrast, Figure 3 shows an embodiment of the present disclosure in which the use of shaped S-strands and Z-strands results in a flattened braided sheath with reduced texturing and surface roughness compared to the conventional core-sheath structure 5 shown in Figure 2.

[0034] 3 shows a cross-section of a core-sheath structure 85 of the present disclosure having a central core 10 surrounded by a flat braided jacket (sheath) 90 formed from shaped untwisted S-strands and untwisted Z-strands 95 and 100 having a cross-sectional aspect ratio of at least 3:1. The shaped S-strands and Z-strands 95 and 100 are braided along a braid axis (not shown) that extends outward in a direction perpendicular to the "plane P" 50 of the core 10. As shown in FIG. 3, the side of the braided jacket (sheath) 90 includes significantly smaller protrusions 105 (where the shaped S-strands and Z-strands 95 and 100 overlap) compared to the protrusions 35 in the braided jacket 15 shown in FIG. 2.

[0035] FIG. 3 also shows the maximum and minimum diameters (D max &D min ) 110 and 115. D max 110 is the maximum diameter measured between the projections 120 and 120′ located on opposite sides of the braided sheath 90, while D min 115 is the smallest diameter measured between non-overlapping S or Z strands 125 and 125' located on opposite sides of braided sheath 90.

[0036] Importantly, the D of the braided sheath 90 in FIG. max and D min The difference between 100 and 115 (△D) (△D=D max -D min ) is significantly less than the difference ΔD for the braided sheath 15 shown in FIG. 2 due to the presence of the shaped S and Z strands 95 and 100 in the braided sheath 90 shown in FIG.

[0037] The flattened braided sheath 90 in the core-sheath structure 85 shown in Figure 3 is formed using untwisted strands 95 and 100 in both the S and Z directions that are shaped to have a cross-sectional aspect ratio of at least 3:1, resulting in significantly smaller protrusions 105 compared to the protrusions 35 shown in Figure 2. As a result, the use of shaped S and Z strands 95 and 100 in Figure 3 results in a flattened braided sheath 90 that has reduced texturing and surface roughness compared to the conventional core-sheath structure 5 shown in Figure 2.

[0038] <Method for manufacturing core-sheath structure> Embodiments described herein include methods for manufacturing a core-sheath structure having a shape-controlled jacket with regions of reduced thickness. Some embodiments relate to methods that include (i) shaping at least one filament bundle comprising a plurality of filaments to form at least one shaped-filament strand, and then (ii) braiding a plurality of strands, including the at least one shaped-filament strand, onto a core to form a core-sheath structure comprising a braided sheath of strands surrounding the core. Such methods may be implemented such that (a) the shaped-filament strands are no-twist strands having a twist level of less than 1 turn per meter, (b) the shaped-filament strands have a cross-sectional aspect ratio of at least 3:1 as measured at the braided sheath, (c) at least a portion of the braided sheath has a thickness in the range of about 10 to about 200 μm, and / or (d) the braided sheath comprises synthetic fibers having a tensile strength greater than 12 cN / dtex.

[0039] 4A-4C show a braiding device that can be used to manufacture the core-sheath structures of the present disclosure.

[0040] FIG. 4A illustrates one embodiment of a braiding device 130 that can be used to manufacture the core-sheath structure of the present disclosure. The braiding device 130 includes a main enclosure 135 that rotates during operation and carries twelve (12) carriers 140 that move independently along the top surface of the main enclosure 135 in a circular carrier path 145 that allows the carriers 140 to describe a continuous "figure eight" pattern. Each carrier 140 includes a bobbin 150 that allows distribution of a filament bundle 155 via a guide 160 that directs the filament bundle 155 toward a central winding shaft 165 that moves axially under the control of a winding shaft movement mechanism 170. While FIG. 4A illustrates a drawing direction for each bobbin 150, a winding direction for each bobbin 150 can also be used.

[0041] Aside from modifications to the braiding device 130 regarding the central winding shaft 165, which may be implemented to allow for more efficient shaping of the at least one filament bundle 155 prior to braiding, the braiding device 130 functions in a manner similar to conventional braiding devices. That is, a tubular braided sheath may be formed on a core (depicted in FIG. 4A as the central winding shaft 165) by diagonally crossing the strands (including at least one preformed strand) in such a way that each group of strands alternately passes over and under a group of strands laid in the opposite direction.

[0042] In some embodiments, modifications may be made to commercially available braiding devices that allow the braiding device to more efficiently form at least one filament bundle. Braiding devices are commercially available, and units with different capabilities may be available. Suitable braiding devices include commercially available braiding devices from Steeger USA (Inman, South Carolina, USA), Herzog GmbH (Oldenburg, Germany), and other manufacturers that are designed for braiding fine-denier filaments and bundles. However, the devices available for modification are not limited to a particular manufacturer. Integral to the sheath core design is a braiding device capable of braiding around a central core. The upper and lower limits for the number of carriers included in the braiding device are not limited and may be determined according to the desired braid parameters and design. As described in more detail below, some embodiments include the use of a braiding device capable of producing a triaxial braid including longitudinal strands.

[0043] In some embodiments, improvements may be implemented in at least one carrier 140 that enable the braiding device to more efficiently shape at least one filament bundle 155. FIG. 4B shows one embodiment of an improved braid carrier 175, including a carrier plate 180, a bobbin 150, at least one strand guide 160 (two are depicted in the embodiment of FIG. 4B), a self-adjusting swivel 185, and a forming device 190. The improved braid carrier 175 includes the additional functionality of directing unshaped filament bundles 195 to the forming device 190, which forms the filament bundles 195 into shaped filaments 200 before the shaped strands 200 are braided about a central take-up shaft (core) 165 (see FIG. 4A).

[0044] In some embodiments, at least one filament-shaped strand may be formed by molding a heated filament bundle, an agitated filament bundle, or a combination thereof. The molding process may be improved to obtain a filament-shaped strand with a higher cross-sectional aspect ratio, for example, by using a heated filament bundle containing at least one of a lubricant, a fiber, and a surface-coated filament. The presence of a lubricant can improve the heat molding process by reducing the viscosity of the lubricant. For example, an agitated filament bundle may be obtained by subjecting the filament bundle to ultrasound.

[0045] Many designs and functions of forming apparatus 190 may be used in the improved braid carrier 175 of the present disclosure. For example, FIG. 4C illustrates an embodiment in which the forming apparatus 205 includes two rollers 210 over which the unshaped filament bundle 195 passes sequentially under tension to produce the filament-shaped strand 200. In other embodiments, the forming apparatus 190 functions by applying tension to the filament bundle 195 on at least one surface (e.g., at least one roller) to compress the filament bundle, or by applying tension to the filament bundle 195 on at least one curved surface so that the filaments separate from one another to form flattened fiber bands. In other embodiments, forming may include forcing the filament bundle between two surfaces (e.g., two rollers). In still other embodiments, forming may include a gating step in which the filaments in the filament bundle pass through separate spaces (e.g., gates, openings) to separate the filaments (as single filaments or as groups of filaments) from one another to form flattened fiber bands.

[0046] The molding process of the present disclosure is not limited to molding performed on the carrier 140, but may also include the use of a molding device disposed between the carrier 140 and the central winding shaft (core) 165 (see FIG. 4A). That is, the molding process may occur on the carrier, between the carrier and the central winding shaft (core), or a combination thereof. The molding device disposed between the carrier and the central winding shaft (core) may employ a similar design and functionality to the molding device on the carrier, or may employ a different design and functionality.

[0047] The shaping process of the present disclosure can be used to form filament-shaped strands having a wide variety of different cross-sectional shapes. For example, shaping can be performed so that the filament-shaped strands have cross-sections that include curved surfaces, so that the filament-shaped strands have cross-sections that include flat surfaces, or a combination thereof. In some embodiments, the filament-shaped strands can have elliptical cross-sections, and in other embodiments, the filament-shaped strands can have curved cross-sections that include convex and / or concave portions. In other embodiments, shaping can be performed so that the filament-shaped strands are flat fiber bands having cross-sections that include flat surfaces.

[0048] FIG. 5 illustrates two non-limiting embodiments in which shaping of a filament bundle 215 containing multiple filaments 220 produces a filament oval-shaped strand 225 or a flat fiber band 230 having a cross-section that includes a plane. As shown in filament oval-shaped strand 225, in some embodiments, the width of a filament shaped strand having a curved cross-section may include at least two monofilaments 235 stacked in a direction transverse to the width of the shaped strand. As shown in flat fiber band 230, in some embodiments, the width of a filament shaped strand may include a single layer of monofilaments 240 arranged side by side. FIG. 6 illustrates the aspect ratio calculation for a filament shaped strand 245 having a curved (oval) cross-section.

[0049] In some embodiments, the braided sheath of the present disclosure may include at least one filament oval-shaped strand having an aspect ratio in the range of about 67% to about 98%. The aspect ratio (%) is calculated by the following formula:

number

[0050] As explained above, when surface coverage is less than 100%, gaps 45 (see FIG. 1) may exist within the braided sheath 15. The braiding method of the present disclosure may include techniques for optimizing the braid pattern of the braided sheath 15 to eliminate gaps 45 and maximize surface coverage. Figures 7A and 7B show the before and after effects of implementing the optimization technique on the braiding method of the present disclosure.

[0051] FIG. 7A shows the surface of a non-optimized braided sheath 250 having less than 85% surface coverage and containing numerous gaps 45. In this particular example, the braided sheath 250 is formed from four filament-shaped strands, including two right-handed braided Z strands 255 and 260 (shown as strands "A" and "C" in FIG. 7A) and two left-handed braided S strands 265 and 270 (shown as strands "B" and "D" in FIG. 7A). The actual braid pattern may vary according to the pattern of crossovers. Common patterns may include plain weave, twill weave, and Panama weave, as well as other braid patterns known to those skilled in the relevant art.

[0052] Factors that may be varied to adjust and optimize the properties of the braided sheath include the pick count of the braiding process, the number of braid ends (strands), and the width of the filament-shaped strands in the braided sheath. Assuming the number of braid ends and shaped strand width are held constant, increasing the pick count during the braiding process tends to increase the surface coverage (and decrease the size of the gaps) of the resulting braided sheath. Assuming the braid pick count and shaped strand width are held constant, increasing the number of braid ends also tends to increase the surface coverage (and decrease the size of the gaps) of the resulting braid. Assuming the braid pick count and number of braid ends are held constant, increasing the shaped strand width also tends to increase the surface coverage (and decrease the size of the gaps) of the resulting braid.

[0053] As an example of braid optimization, a core-sheath structure having a four-strand braided sheath is formed on a colored (high-visibility) core material using the method of the present disclosure. The four strands include two right-handed braided Z-strands (designated as strands "A" and "C") and two left-handed braided strands (designated as strands "B" and "D") (see FIG. 7A). During the two-step method (forming and then braiding) of the present disclosure, the pick count of the braided sheath is gradually increased while keeping the number of braid ends and the width of the formed strands constant. The width of the formed strands is kept constant by maintaining constant tension on the filament bundle passing through the forming device 190 (see, e.g., FIG. 4B) during the forming process. As the pick count is gradually increased, a core-sheath (cord) structure is produced, including different sections corresponding to the different pick counts produced.

[0054] The resulting core-sheath (cord) structure is then visually analyzed using a microscope to measure the size of the gaps 45 in different sections corresponding to different pick counts. For example, the size of the gaps 45 can be measured using a digital microscope with an optical magnification of about 200x, such as a DINO-LITE™ USB digital microscope. The optimal pick count is determined based on sections where the gaps 45 are small enough to result in about 95% surface coverage. In another example, the optimal pick count is where the gaps 45 are small enough to result in a surface coverage ranging from about 80% to about 99%.

[0055] Using an optimal pick count, another core-sheath structure having a four-strand braided sheath is formed on a colored (high-visibility) core material using the method of the present disclosure. While the pick count is held constant at the optimal pick count during the two-step process (forming and then braiding), the width of the formed strand is gradually increased by increasing the tension on the filament bundle passing through the forming device 190 (see, e.g., FIG. 4B) during the forming process. As the tension on the filaments passing through the forming device 190 is gradually increased, a core-sheath (cord) structure is produced that includes different sections corresponding to different widths of the formed strand.

[0056] The resulting core-sheath (cord) structure is then visually analyzed using a microscope to measure the size of the gaps 45 in different sections corresponding to different widths of the filament-formed strand. The optimal width is determined based on the section where the gaps 45 disappear, corresponding to approximately 100% surface coverage. In other examples, the optimal width is where the gaps 45 are small enough to produce a surface coverage ranging from approximately 90% to approximately 100%. Some core-sheath structures may be optimized so that gaps are intentionally contained within the jacket (sheath) or so that the strands forming the jacket (sheath) can overlap. Thus, the surface coverage of an optimized core-sheath structure may range from approximately 25% to approximately 150%, depending on the intended application.

[0057] 7B shows the surface of the optimized braided sheath 275 with approximately 100% surface coverage, with the right-hand braided Z strands 255 and 260 (designated as strands "A" and "C") and the left-hand braided S strands 265 and 270 (designated as strands "B" and "D") closely packed together without gaps or significant overlap. FIG. 7B also shows the braid axis 280 of the core-sheath structure, along with the optimized braid angle (θ) 285, directional bias 290, distance (S) 295, and strand width (W) 300 of the optimized braided sheath 275.

[0058] Other braid optimization methods may be used, where pick count, number of ends, and strand width are adjusted in different orders to achieve different levels of surface coverage, with or without gaps. In some embodiments, the surface coverage of the braided sheath over the core is at least 85%. In other embodiments, the surface coverage may range from about 25% to about 100%. In still other embodiments, the surface coverage may be greater than 100%, such that adjacent strands at least partially overlap one another. As discussed above, in some embodiments, the surface coverage may range from about 25% to about 150%. For example, the surface coverage may range from about 50% to about 125%, or from about 75% to about 110%, or from about 85% to about 105%, or from about 90% to about 100%.

[0059] As explained above, in some optimized core-sheath structures, the surface coverage may be significantly less than 100% (due to the intentional presence of gaps) or significantly more than 100% (due to overlapping strands of the jacket (sheath)). Such embodiments may be advantageous, for example, when it is beneficial to have a higher surface roughness of the jacket (sheath) (due to the presence of gaps and / or protrusions) or when additional protection for the core is desired (due to the presence of overlapping strands).

[0060] The pick count of the braided sheath in a relaxed state (i.e., in its natural, resting state with no tension applied to the core-sheath structure) may range from 30 to 3000 filament-unit crossovers per meter. In other embodiments, the pick count of the braided sheath in a relaxed state may range from about 30 to 3000 crossovers per meter, or from about 50 to about 2000 crossovers per meter, or from about 50 to 1000 crossovers per meter.

[0061] The number of strands (ends) in the braided sheath is determined by the requirements of the core-sheath structure and the performance of the braided device. Depending on the particular application, strand counts ranging from 4 to over 200 can be employed. In some embodiments, the number of strands (ends) in the braided sheath can range from 4 to 96 ends, while in other applications, a number limited to about 24 ends may be appropriate. For example, the number of strands (ends) in the core-sheath structures of the present disclosure can range from 4 to 24 ends, or 4 to 16 ends, or 4 to 12 ends, or 4 to 8 ends, or 4 to 6 ends. In medical applications, the core-sheath structures of the present disclosure often range from 4 to 24 ends.

[0062] The braid angle of the braided sheath in a relaxed state is generally in the range of about 5° to about 85°. In other embodiments, the braid angle of the S-strands and Z-strands of the braided sheath in a relaxed state can be in the range of about 5° to about 60°, or about 10° to about 75°, or about 15° to about 60°, or about 20° to about 45°, or about 5° to about 45°.

[0063] The selection of the braid angle can have a significant effect on the properties of the core-sheath structures of the present disclosure. For example, a smaller braid angle tends to increase the modulus and / or strength of the resulting core-sheath structure because the load-bearing fibers of the jacket (sheath) are more aligned in the direction of the load (i.e., along the braid axis 25). The selection of the braid angle can also be used to control the load sharing between the core and jacket (sheath). In some embodiments, balancing the load sharing between the core and jacket (sheath) is important to obtain a core-sheath structure with optimal tensile strength and durability properties.

[0064] <Articles with core-sheath structure> Embodiments of the present disclosure also include core-sheath structures manufactured by the above-described methods. For example, some embodiments relate to core-sheath structures including (I) a core and (II) a braided sheath of strands surrounding the core, wherein the braided sheath includes strands having a braid angle of 5° or greater in a relaxed state, and the strands having a braid angle of 5° or greater in a relaxed state include at least one shaped filament strand. Such core-sheath structures may be manufactured such that (A) the shaped filament strands are untwisted strands having a twist level of less than 1 turn per meter, (B) the shaped filament strands have a cross-sectional aspect ratio of at least 3:1 as measured at the braided sheath, (C) at least a portion of the braided sheath has a thickness in the range of about 20 to about 200 μm, and / or (D) the braided sheath includes synthetic fibers having a tensile strength greater than 12 cN / dtex.

[0065] The core-sheath structures of the present disclosure include embodiments in which the braided sheath includes at least one untwisted filament shaped strand having a twist level of less than 0.75 turns per meter, or less than 0.5 turns per meter, or less than 0.25 turns per meter.

[0066] In some embodiments, the cross-sectional aspect ratio of the filament shaped strands is in the range of 3:1 to 50:1, or in the range of 3:1 to 20:1, or in the range of 4:1 to 15:1, or in the range of 5:1 to 10:1. In other examples, the cross-sectional aspect ratio of the filament shaped strands can be in the range of about 3:1 to about 50:1 (about 68 to 98% flattening), or about 4.1:1 to about 50:1 (about 75.5 to 98% flattening), or about 5.6:1 to about 50:1 (about 82 to 98% flattening), or about 8:1 to about 22.2:1 (about 87.5 to 95.5% flattening).

[0067] The thickness of at least a portion of the braided sheath can range from about 16 μm to about 250 μm, or from about 40 μm to about 200 μm, or from about 50 μm to about 175 μm, or from about 60 μm to about 150 μm, or from about 50 μm to about 125 μm.

[0068] As discussed above, the braided sheath of the present disclosure may include synthetic fibers having a tensile strength greater than 12 cN / dtex. The synthetic fibers may have a tensile strength of at least 13 cN / dtex, or at least 15 cN / dtex, or at least 20 cN / dtex. In some embodiments, the synthetic fibers included in the braided sheath may have a tensile strength in the range of 13 cN / dtex to 50 cN / dtex, or 15 cN / dtex to 45 cN / dtex.

[0069] In addition to synthetic fibers having a tensile strength greater than 12 cN / dtex, the braided sheath in the core-sheath structures of the present disclosure may include other synthetic and non-synthetic fibers and filaments having a tensile strength ranging from about 1 cN / dtex to about 30 cN / dtex. For example, some embodiments include core-sheath structures that include a braided sheath that includes synthetic fibers having a tensile strength greater than 12 cN / dtex and synthetic or non-synthetic fibers having a tensile strength less than 12 cN / dtex. In other embodiments, the braided sheath does not include synthetic fibers having a tensile strength less than 12 cN / dtex. The braided sheath of the present disclosure may also include both synthetic fibers having a tensile strength greater than 12 cN / dtex and non-synthetic fibers having a tensile strength greater than 12 cN / dtex.

[0070] The filament shaped strand may have a tensile strength greater than 12 cN / dtex, or may have a tensile strength in the range of about 1 cN / dtex to about 45 cN / dtex.

[0071] As described above, the methods of the present disclosure include shaping at least one filament bundle including a plurality of filaments to form at least one shaped filament strand. In some embodiments, the plurality of filaments included in the filament bundle may include at least one filament having a non-circular cross-section. Such a filament having a non-circular cross-section may be formed by an extrusion process using an extrusion die having a non-circular cross-sectional profile. For example, the filament bundle of the present disclosure may include at least one filament having an elliptical cross-section, a triangular cross-section, a square cross-section, a polygonal cross-section, a hollow cross-section, or any other cross-section known to be produced by extrusion.

[0072] Core-sheath structures of the present disclosure may also include core-sheath structures having a maximum diameter (outer diameter) ranging from about 15 μm to about 20 mm. In other embodiments, the outer diameter of the core-sheath structure may range from about 20 μm to about 8 mm, or from about 30 μm to about 5 mm, or from about 50 μm to about 3 mm, or from about 50 μm to about 1 mm.

[0073] A wide variety of core sizes may be used in embodiments of the present disclosure. For example, the maximum diameter of the core may range from about 10 μm to about 20 mm. In other embodiments, the maximum diameter of the core may range from about 15 μm to about 10 mm, or from about 25 μm to about 5 mm, or from about 50 μm to about 1 mm, or from about 50 μm to about 500 μm.

[0074] The core-sheath structures of the present disclosure may employ twisted or untwisted cores, as well as monofilament cores. In some embodiments, the core comprises at least two core strands twisted together at a twist level of greater than 0 to 1600 turns per meter. The number of core strands included in a twisted or untwisted core may range from 1 to 500, and the twist level of the core or core strands used to produce a multi-strand core may range from 1 to 1600 turns per meter. Combinations of twisted, untwisted, and / or braided filaments may also be used to produce the core in the core-sheath structures of the present disclosure.

[0075] 8 shows a cross-section of one embodiment of the present disclosure in which core-sheath structure 305 includes a twisted three-strand core including three strands 310 twisted together at a twist level of greater than 0 to 1600 turns per meter so that the core has a triangular cross-section. In this embodiment, the triangular three-strand core is surrounded by a flat braided jacket (sheath) 315 formed from untwisted S- and Z-strands 320 and 325 shaped to have a cross-sectional aspect ratio of at least 3:1. Due to the relatively small size of the projections 330 where the S- and Z-strands 320 and 325 overlap, the flat braided sheath 315 closely conforms to the outer surface of the core such that the cross-sectional shape of the outer surface of the sheath 315 generally mimics the shape of the outer surface of the triangular core.

[0076] As explained above, the manufacturing method of the present disclosure can be advantageous because the ability to form the filament bundle into at least one shaped filament strand allows the resulting core-sheath structure to have a thinner braided sheath with less texturing and less surface roughness compared to conventional core-sheath structures. For example, as shown in a comparison of Figures 2 and 3, the maximum diameter (D max ) 110 and the minimum diameter of the braided sheath (D min )115 and the difference between (△D)(△D=D max -D min ) is significantly smaller than the difference ΔD of the braided sheath 15 shown in FIG. max :D min In another embodiment, the ratio of D max :D min is in the range of about 1.1:1 to about 1.5:1, or about 1.05:1 to about 1.35:1, or about 1.1:1 to about 1.3:1, or about 1.1:1 to about 1.2:1.

[0077] Another measure of the ability to form a bundle of filaments into a shaped strand is the flattening factor of the filament-shaped strand. For a core-sheath structure comprising a circular core with a circular cross section and a braided sheath made of shaped strands with a surface coverage of 100% or less, the flattening factor is:

number

[0078] Embodiments of the present disclosure include core-sheath structures including a circular core having a circular cross section and a braided sheath of shaped strands, wherein the shaped strands have a flatness factor ranging from about 0.05 to about 0.45. In other embodiments, the flatness factor may range from about 0.1 to about 0.35, or from about 0.10 to about 0.30, or from about 0.1 to about 0.25.

[0079] In some embodiments, the core in the core-sheath structure is a surface-treated core. For example, the surface of the core component may be corona- or plasma-treated prior to application of the braided sheath. Such treatments may create surface imperfections or modifications that enhance contact (surface interaction) between the core and the inner surface of the braided sheath, further enhancing the interaction between the core and the braided sheath.

[0080] Another aspect of the present disclosure relates to the percentage of strands used in the braiding process that are shaped strands. In some embodiments, all of the strands used in the braiding process are shaped strands, while in other embodiments, only a portion of the strands used in the braiding process are shaped strands. For example, in some embodiments, all of the S strands braided in the left-hand direction are shaped strands, while all of the Z strands braided in the right-hand direction are non-shaped strands that have not been subjected to a shaping process prior to the braiding process, or vice versa. In still other embodiments, only a portion of one or both of the S and Z strands may be shaped strands. Embodiments of the present disclosure include core-sheath structures that include only one shaped strand in the braided sheath, or core-sheath structures that include all (100%) shaped strands in the braided sheath, or core-sheath structures that include any combination between one shaped strand and 100% shaped strands in the braided sheath.

[0081] Embodiments of the present disclosure also include core-sheath structures in which the braided sheath is a hybrid jacket comprising at least one shaped strand of filaments having a cross-sectional aspect ratio of at least 3:1 and at least one unshaped strand of filaments having a cross-sectional aspect ratio of less than 2:1. For example, in some embodiments, the braided sheath is a hybrid jacket comprising at least one shaped strand of filaments having a cross-sectional aspect ratio of at least 3:1 and at least one twisted (unshaped) strand of filaments having a twist level of greater than 0 to 1600 turns per meter. As explained above, twisted filament bundles (i.e., twisted strands) are more rigid and less moldable than untwisted filament bundles.

[0082] Hybrid jackets of the present disclosure may be formed using filament bundles (strands) containing filaments of different diameters (different linear densities). For example, a hybrid jacket may be formed by interweaving high-density strands (formed with high-density filaments, e.g., 10-30 denier per filament (dpf) filaments) and low-density strands (formed with low-density filaments, e.g., 2.5-10 dpf filaments). Filament bundles formed with high-density (high dpf) filaments are stiffer and more resistant to crushing, but may be more difficult to shape (flatten) using a compression mechanism, while filament bundles formed with low-density (low dpf) filaments are softer and more flexible, but may be more fragile. Core-sheath structures in some embodiments of the present disclosure include hybrid jackets formed with high-dpf filament-shaped strands (10 dpf or greater) woven in the S direction and low-dpf filament-shaped strands (less than 10 dpf) woven in the Z direction, or vice versa. Embodiments also include the use of non-shaped strands of high dpf filaments and / or low dpf filaments. The use of high dpf strands woven in only one direction can result in a core-sheath structure that exhibits high torsional stiffness in only one rotational direction.

[0083] FIG. 9 shows a cross-section of a core-sheath structure 335 of the present disclosure, having a circular core 10 surrounded by a hybrid braided jacket (sheath) 340 formed from shaped S-strands 345 having a cross-sectional aspect ratio of at least 3:1 and non-shaped Z-strands 350 having a cross-sectional aspect ratio of less than 2:1. A comparison of FIG. 3 and FIG. 9 indicates that the presence of non-shaped Z-strands 350 in the embodiment shown in FIG. 9 results in larger protrusions 355 where the shaped S-strands 345 and non-shaped Z-strands 350 overlap, compared to the embodiment shown in FIG. 3, which includes only shaped S-strands and shaped Z-strands 95 and 100 in the braided sheath 90. Thus, an embodiment such as the example shown in FIG. 9, having a hybrid braided sheath, may allow for control over the texture and surface area of ​​the outer surface of the resulting core-sheath structure.

[0084] The core-sheath structure of the present disclosure may also include a triaxially braided sheath including longitudinal strands having a braid angle of less than 5° in a relaxed state in addition to the left-handed braided S-strands 20 and right-handed braided Z-strands 30 (see FIG. 1 ). In some embodiments, the triaxially braided sheath may include at least one shaped longitudinal strand formed by shaping at least one longitudinal strand prior to braiding multiple strands. For example, the triaxially braided sheath of the present disclosure may include one shaped longitudinal strand, all shaped longitudinal strands, or any combination in between, in addition to the S-strands and Z-strands.

[0085] FIG. 10 shows a core-sheath structure 360 ​​including a central core 10 partially surrounded by a triaxial braided jacket (sheath) 365 formed from S strands 20 braided in a left-handed twist direction along the braid axis 25 of the core 10, Z strands 30 braided in a right-handed twist direction along the braid axis 25, and longitudinal strands 370 braided along the braid axis 25 and having a braid angle of less than 5° in the relaxed state.

[0086] The core-sheath structure of the present disclosure may be formed such that the filament bundle further comprises a lubricant, a fiber, a surface-coated filament, or a combination thereof. The lubricant used in the filament bundle of the present disclosure may comprise at least one of a lubricant filament and a lubricant fiber. The surface-coated filament may comprise a crosslinked or non-crosslinked silicone polymer as a surface coating.

[0087] The mass ratio of the braided sheath to the core per unit length of the core-sheath structure may range from about 2 / 98 to about 98 / 2. In other embodiments, the mass ratio of the braided sheath to the core per unit length of the core-sheath structure is from about 2 / 98 to about 80 / 20, or from about 3 / 98 to about 75 / 25, or from about 4 / 98 to about 60 / 40, or from about 5 / 95 to about 45 / 55, or from about 20 / 80 to about 90 / 10, or from about 30 / 70 to about 80 / 20, or from about 40 / 60 to about 70 / 30. In some embodiments, the linear mass density of the braided sheath is greater than the linear mass density of the core. In other embodiments, the linear mass density of the braided sheath is equal to the linear mass density of the core, or the linear mass density of the braided sheath is less than the linear mass density of the core.

[0088] The core-sheath structures of the present disclosure may have a linear mass density ranging from about 30 denier to about 10,000 denier. In other embodiments, the linear mass density of the core-sheath structure may range from about 40 denier to about 4500 denier, or from about 50 denier to about 4000 denier, or from about 100 denier to about 3000 denier, or from about 70 denier to about 2000 denier, or from about 80 denier to about 1500 denier, or from about 90 denier to about 1000 denier.

[0089] As discussed above, methods of the present disclosure may include shaping at least one filament bundle comprising a plurality of filaments to form at least one shaped filament strand. In some embodiments, the plurality of filaments comprises filaments having a linear mass density ranging from about 0.1 to about 30 denier. In other embodiments, the linear mass density of the filaments may range from about 0.2 to about 10 denier, or from about 0.4 to about 8.0 denier, or from about 0.6 to about 6.0 denier.

[0090] The shaped and / or unshaped strands of a braided sheath may be identical in size, structure, and composition, or the strands may differ in any or all of size, structure, and composition. Thus, a braided sheath may be composed of strands of different denier, braid, or twist. Furthermore, a braided sheath may include strands of different chemical compositions. Thus, the braided sheaths of the present disclosure may be designed to control the strength and torque characteristics of the core-sheath structure.

[0091] The chemical composition of the strands (or filaments) of the braided sheath may be any high performance polymer known to provide a combination of high tensile strength, high tenacity, and low creep, and may be selected from, but is not limited to, liquid crystal polyester filaments, aramid filaments, copolymer aramid filaments, polyether ether ketone filaments, poly(p-phenylene benzobisoxazole) (PBO) filaments, ultra-high molecular weight polyethylene filaments, high modulus polyethylene filaments, polypropylene filaments, polyethylene terephthalate filaments, polyamide filaments, high tenacity polyvinyl alcohol filaments, polyhydroquinone diimidazopyridine (PIPD) filaments, and combinations thereof, to name just a few.

[0092] Polyhydroquinone diimidazopyridine (PIPD) filament fibers are based on a polymer of the following repeating units: [ka]

[0093] In some embodiments, the plurality of filaments included in the braided sheath comprise at least one selected from liquid crystal polyester filaments, aramid filaments, copolymer aramid filaments, polyetheretherketone filaments, poly(p-phenylenebenzobioxazole) filaments, ultra-high molecular weight polyethylene filaments, high modulus polyethylene filaments, polypropylene filaments, polyethylene terephthalate filaments, polyamide filaments, polyhydroquinone diimidazopyridine filaments, and high strength polyvinyl alcohol filaments, while in other embodiments, the plurality of filaments comprise at least two of these materials.

[0094] In some embodiments, the shaped and / or non-shaped strands of the braided sheath may comprise at least one fiber selected from liquid crystal polyester fibers, aramid fibers, PBO fibers, ultra-high molecular weight polyethylene fibers, and high-strength polyvinyl alcohol fibers. In other embodiments, the shaped and / or non-shaped strands of the braided sheath may be selected from liquid crystal polyester fibers and aramid fibers, particularly liquid crystal polyester fibers.

[0095] The core-sheath structure of the present disclosure, in some embodiments, may include a core comprising at least one selected from the group consisting of liquid crystal polyester filaments, aramid filaments, copolymer aramid filaments, polyether ether ketone filaments, poly(phenylene benzobisoxazole) filaments, ultra-high molecular weight polyethylene filaments, polypropylene filaments, high modulus polyethylene filaments, polyethylene terephthalate filaments, polyamide filaments, and high strength polyvinyl alcohol filaments.

[0096] Polymerized units include those shown in Table 1.

[0097] [Table 1]

[0098] With respect to the polymerized units shown in Table 1 above, the number of substituents Y is equal to the maximum number of substitutable positions in the ring structure, and each Y independently represents a hydrogen atom, a halogen atom (e.g., a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc.), an alkyl group (e.g., an alkyl group having 1 to 4 carbon atoms, such as a methyl group, an ethyl group, an isopropyl group, or a t-butyl group), an alkoxy group (e.g., a methoxy group, an ethoxy group, an isopropoxy group, an n-butoxy group, etc.), an aryl group (e.g., a phenyl group, a naphthyl group, etc.), an aralkyl group [benzyl group (phenylmethyl group), phenethyl group (phenylethyl group), etc.], an aryloxy group (e.g., a phenoxy group, etc.), an aralkyloxy group (e.g., a benzyloxy group, etc.), or a mixture thereof.

[0099] Liquid crystal polyester fibers can be obtained by melt-spinning a liquid crystal polyester resin. The spun fibers may be further heat-treated to improve mechanical properties. The liquid crystal polyester may be composed of repeating polymerized units derived from, for example, an aromatic diol, an aromatic dicarboxylic acid, or an aromatic hydroxycarboxylic acid. The liquid crystal polyester may optionally further contain polymerized units derived from an aromatic diamine, an aromatic hydroxyamine, and / or an aromatic aminocarboxylic acid.

[0100] More specific polymer units are shown in the structures shown in Tables 2 to 4 below.

[0101] When the polymerized unit in the formula is a unit that can represent a plurality of structures, two or more units may be used in combination as the polymerized unit that constitutes the polymer.

[0102] In the polymerization units in Tables 2, 3, and 4, n is an integer of 1 or 2, and each unit n=1 and n=2 may exist alone or in combination; Y1 and Y2 each independently represent a hydrogen atom, a halogen atom (e.g., a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc.), an alkyl group (e.g., an alkyl group having 1 to 4 carbon atoms, such as a methyl group, an ethyl group, an isopropyl group, or a t-butyl group), an alkoxy group (e.g., a methoxy group, an ethoxy group, an isopropoxy group, an n-butoxy group, etc.), an aryl group (e.g., a phenyl group, a naphthyl group, etc.), an aralkyl group (e.g., a benzyl group (phenylmethyl group), a phenethyl group (phenylethyl group), etc.), an aryloxy group (e.g., a phenoxy group), an aralkyloxy group (e.g., a benzyloxy group), or a mixture thereof. Of these groups, Y is preferably a hydrogen atom, a chlorine atom, a bromine atom, or a methyl group.

[0103] [Table 2]

[0104] [Table 3]

[0105] [Table 4]

[0106] Z in type (14) of Table 3 may include a divalent group represented by the formula: [ka]

[0107] In some embodiments, the liquid crystal polyester may be a combination containing a naphthalene skeleton as a polymerized unit. In particular, the liquid crystal polyester may contain both polymerized units (A) derived from hydroxybenzoic acid and polymerized units (B) derived from hydroxynaphthoic acid. For example, the units (A) may be represented by formula (A), and the units (B) may be represented by formula (B). From the viewpoint of improving melt moldability, the ratio of the units (A) to the units (B) may be in the range of 9 / 1 to 1 / 1, preferably 7 / 1 to 1 / 1, and more preferably 5 / 1 to 1 / 1. [ka]

[0108] The sum of the polymerized units (A) and the polymerized units (B) may be, for example, about 65 mol % or more, about 70 mol % or more, or about 80 mol % or more, based on the total polymerized units. In some embodiments, the braided sheath may include a liquid crystal polyester containing about 4 to about 45 mol % of the polymerized units (B) in the polymer.

[0109] The melting point used herein refers to the main absorption peak temperature measured and observed using a differential scanning calorimeter (DSC) (e.g., a "TA3000" manufactured by METTLER Co.) in accordance with the JIS K7121 test method. Specifically, a 10-20 mg sample is used in the DSC apparatus. The sample is sealed in an aluminum dish, and then nitrogen is flowed as a carrier gas at a flow rate of 100 cc / min. The endothermic peak is measured when the sample is heated at a rate of 20°C / min. Depending on the type of polymer, if no clear peak appears in the initial DSC measurement, the temperature is increased to a temperature 50°C higher than the expected flow temperature at a heating rate of 50°C / min, and then the polymer is completely dissolved at the same temperature for 3 minutes. The endothermic peak may then be measured at a heating rate of -80°C / min.

[0110] Commercially available LCPs for inclusion in the braided sheaths of the present disclosure may include VECTRAN® HT BLACK manufactured by Kuraray Co., Ltd., VECTRAN® HT manufactured by Kuraray Co., Ltd., SIVERAS® manufactured by Toray Industries, Inc., ZEUS Monofilament, and ZXION® manufactured by KB SEIREN, LTD.

[0111] The liquid crystalline polyesters may be used alone or in combination in the core-sheath structures of the present disclosure.

[0112] In the present invention, "aramid fiber" refers to a polyamide fiber having high heat resistance and high strength and containing a molecular skeleton composed of aromatic (benzene) rings. Aramid fibers may be classified into para-aramid fibers and meta-aramid fibers depending on their chemical structure, and some braided sheaths of the present disclosure preferably contain para-aramid fibers.

[0113] Examples of commercially available aramid and copolymer aramid fibers include: para-aramid fibers, such as KEVLAR® manufactured by EI du Pont de Nemours and Company, HERACRON® manufactured by Kolon Industries Inc., and TWARON® and TECHNORA® manufactured by Teijin Limited; and meta-aramid fibers, such as NOMEX® manufactured by EI du Pont de Nemours and Company and CONEX® manufactured by Teijin Limited.

[0114] When included in the braided sheath of the present disclosure, aramid fibers may be used alone or in combination. In some embodiments, the filaments included in the shaped and / or unshaped strands used to prepare the braided sheath may comprise copolymer aramid filaments. For example, in some embodiments, the shaped and / or unshaped strands comprise copolyparaphenylene / 3,4'-oxydiphenylene terephthalamide filaments. This material is conventionally referred to as TECHNORA® and is available from Teijin.

[0115] Polyparaphenylene benzobisoxazole (poly(p-phenylene-2,6-benzobisoxazole) (PBO) fibers are commercially available from Toyobo Co., Ltd. under the trade names ZYLON® AS and ZYLON® HM.

[0116] The core-sheath structures of the present disclosure may also be formed from polyetheretherketone (PEEK) materials, such as VICTREX® PEEK polymer. In some embodiments, the use of high dpf PEEK polymer as a component of the jacket (sheath) and / or core can impart improved tensile properties to the core-sheath structure.

[0117] The ultra-high molecular weight polyethylene fibers used in the core-sheath structure of the present disclosure may have an intrinsic viscosity in the range of about 5.0 dL / g or more, or about 7.0 dL / g or more, or about 10 dL / g or more, and about 30 dL / g or less, or about 28 dL / g or less, or about 24 dL / g or less. When the intrinsic viscosity of the "ultra-high molecular weight polyethylene fibers" is in the range of about 5.0 dL / g to about 30 dL / g, fibers with good dimensional stability can be obtained.

[0118] For certain polymers, such as nylon, polyvinyl chloride, polyethylene, and poly(ethylene terephthalate), ASTM standards describing procedures for measuring dilute viscosity (e.g., Test Methods D789, D1243, D1601, and D4603, and Practice D3591) can be used. Typically, the polymer is dissolved in a dilute solution and the fall time through a capillary tube is measured against a control sample at a particular temperature.

[0119] The weight-average molecular weight of the "ultra-high molecular weight polyethylene fiber" may be about 700,000 or more, or about 800,000 or more, or about 900,000 or more, and about 8,000,000 or less, or about 7,000,000 or less, or about 6,000,000 or less. When the weight-average molecular weight of the "ultra-high molecular weight polyethylene fiber" is in the range of about 700,000 to about 8,000,000, high tensile strength and elastic modulus can be obtained.

[0120] Since it is difficult to measure the weight average molecular weight of "ultra-high molecular weight polyethylene fiber" using the GPC method, the following formula described in "Polymer Handbook Fourth Edition, Chapter 4 (John Wiley, published 1999)" was used:

number

[0121] In some embodiments, it may be preferable for the repeating units of "ultra-high molecular weight polyethylene fibers" to substantially contain ethylene. However, in addition to ethylene homopolymers, copolymers of ethylene with small amounts of other monomers, such as α-olefins, acrylic acid and its derivatives, methacrylic acid and its derivatives, and vinylsilane and its derivatives, may be used. The polyethylene fibers may have a partially crosslinked structure. The polyethylene fibers may be a blend of high-density polyethylene and ultra-high molecular weight polyethylene, a blend of low-density polyethylene and ultra-high molecular weight polyethylene, or a blend of high-density polyethylene, low-density polyethylene, and ultra-high molecular weight polyethylene. The polyethylene fibers may be a combination of two or more ultra-high molecular weight polyethylenes having different weight average molecular weights, or a combination of two or more polyethylenes having different molecular weight distributions.

[0122] Commercially available "ultra-high molecular weight polyethylene fibers" include: DYNEEMA® SK60, DYNEEMA® SK, IZANAS® SK60, and IZANAS® SK71 manufactured by Toyobo Co., Ltd.; and SPECTRA FIBER 900® and SPECTRA FIBER 1000 manufactured by Honeywell, Ltd.

[0123] These "ultra-high molecular weight polyethylene fibers" can be used alone or in combination.

[0124] The core composition may be any of the high performance polymer filaments described above, and may be filaments selected from the group consisting of liquid crystal polyester filaments, aramid filaments, copolymer aramid filaments, polyether ether ketone filaments, poly(p-phenylene benzobisoxazole) filaments, ultra-high molecular weight polyethylene filaments, high modulus polyethylene filaments, polypropylene filaments, polyethylene terephthalate filaments, polyamide filaments, high tenacity polyvinyl alcohol filaments, and combinations thereof.

[0125] The composition of the filaments of the core component may be selected and configured for specific properties related to the end use of the core-sheath structure.

[0126] The weave or knit and / or twist of the braided sheath (jacket), along with the polymer composition of the core, may also be adjusted to control the load-sharing contribution of the core and braided sheath. In this way, the overall tensile strength and dimensional stability of the core-sheath structures of the present disclosure can be increased while maintaining or reducing the overall diameter of the core-sheath structure.

[0127] In some embodiments, the core-sheath structures of the present disclosure may include an LCP-based core and an LCP-based braided sheath.

[0128] In some embodiments, the performance and properties of the core-sheath structures of the present disclosure may be improved and tailored by applying a final composition to the core and / or braided sheath. For example, at least one of the core and braided sheath may comprise filaments, fibers, or strands having a coating of a cross-linked silicone polymer, or a non-cross-linked silicone polymer or a long-chain fatty acid. Suitable long-chain fatty acids may include stearic acid.

[0129] The application of cross-linked silicone polymers, particularly to the filaments contained in the strands of the braided sheath and / or core, can provide advantageous performance improvements to the tensile strength of the core-sheath structures of the present invention.

[0130] Generally, there are three crosslinking reaction methods that can be used to prepare silicone resins: 1) peroxide cure, in which thermal activation of polymerization occurs under the generation of peroxide free radicals; 2) condensation in the presence of tin salt or titanium alkoxide catalysts under the influence of heat or moisture; and 3) addition reaction chemistry, which can be initiated by temperature or light and is catalyzed by platinum or rhodium complexes.

[0131] The cross-linked silicone coating may increase the moisture resistance of the coated strands and may also increase the lubricity of the strands so that the braid responds more efficiently when the core-sheath structure is under longitudinal stress compared to an uncoated structure, which may need to overcome frictional interactions.

[0132] The coating composition of the present disclosure may be applied by surface application techniques known to those skilled in the art. These surface application techniques may include simple pumping of the finish solution through a finish guide, where the fiber contacts the finish and is wicked up into the fiber bundle by capillary action. Alternatively, other techniques may include spraying, roll coating, or dip coating techniques such as dip coating. Subsequent treatment of the fiber containing the applied finish solution may include contact with a roller to set the finish and / or control the degree of crosslinking of the finish composition. The roller may be heated or unheated. The coating composition may then be cured to effect crosslinking of the crosslinkable silicone polymer. If heat curing is used, the temperature may be about 20°C or higher, or about 50°C or higher, or about 120°C or higher, or about 200°C or lower, or about 170°C or lower, or about 150°C or lower. The curing temperature may be determined by the thermal stability characteristics of the filament, fiber, or strand used and the crosslinking system.

[0133] The degree of crosslinking obtained may be controlled to impart different degrees of flexibility or other surface properties to the filaments, fibers, or strands. The degree of crosslinking may be measured by the method described in US 8881496 B2, in which the coating is extracted with a solvent that dissolves the monomer but not the crosslinked polymer. The degree of crosslinking may be determined from the difference in weight before and after extraction.

[0134] The degree of cross-linking can be at least about 20%, or at least about 30%, or at least about 50%, based on the total weight of the coating. The maximum degree of cross-linking can be about 100%. The weight of the cross-linked coating can be about 1% by weight or more and about 20% by weight or less, or about 10% by weight or less, or about 5% by weight or less, based on the total weight of the filament, fiber, or strand.

[0135] <Cords and tension members> Another aspect relates to a cord obtained by the method disclosed herein for producing a core-sheath structure. In some embodiments, the maximum diameter of the cord may range from about 15 μm to about 20 mm. In other embodiments, the maximum diameter of the cord may range from about 20 μm to about 5 mm, or from about 30 μm to about 4 mm, or from about 40 μm to about 3.5 mm, or from about 50 μm to about 3 mm, or from about 50 μm to about 2 mm.

[0136] The cords of the present disclosure may be designed to meet a variety of characteristics, including breaking strength. In some embodiments, the cord has a breaking strength of at least 15 cN / dtex. In other embodiments, the cord's breaking strength may range from about 4 cN / dtex to about 40 cN / dtex, or from about 13 cN / dtex to about 31 cN / dtex, or from about 15 cN / dtex to about 26 cN / dtex.

[0137] Cords of the present disclosure include tensile members useful in a variety of applications, including medical cords. For example, embodiments of the present disclosure include sutures having a core-sheath structure manufactured by the methods described herein, as well as catheter navigation cables and assemblies, steering cables and assemblies, device development control cables and assemblies, and torque and tension transmission cables and assemblies, to name but a few.

[0138] Tensile members of the present disclosure may comprise cords having a linear mass density ranging from about 30 denier to about 10,000 denier. In other embodiments, the linear mass density of the tensile members may range from about 40 denier to about 4500 denier, or from about 50 denier to about 4000 denier, or from about 100 denier to about 3000 denier, or from about 70 denier to about 2000 denier, or from about 80 denier to about 1500 denier, or from about 90 denier to about 1000 denier.

[0139] <Embodiment> Embodiment [1] of the present disclosure relates to a method for manufacturing a cord having a core-sheath structure, the method including: shaping at least one filament bundle including a plurality of filaments to form at least one filament-shaped strand; and braiding a plurality of strands including the at least one filament-shaped strand onto a core to form the core-sheath structure including a braided sheath of strands surrounding the core, wherein: the filament-shaped strand is a no-twist strand having a twist level of less than 1 turn per meter; the cross-sectional aspect ratio of the filament-shaped strand is at least 3:1, measured at the braided sheath; at least a portion of the braided sheath has a thickness in the range of about 10 to about 200 μm; and the braided sheath includes synthetic fibers having a tensile strength greater than 12 cN / dtex.

[0140] Embodiment [2] of the present disclosure relates to the method of embodiment [1], wherein the shaping is performed so that the filament shaped strand has a cross-section that includes a curved surface, the shaping is performed so that the filament shaped strand has a cross-section that includes a flat surface, or a combination thereof.

[0141] Embodiment [3] of the present disclosure relates to at least one of the methods of embodiments [1] and [2], wherein the filament-shaped strands have an elliptical cross-section, the filament-shaped strands have a curved cross-section including a convex portion and a concave portion, or the filament-shaped strands are flat fiber bands having a cross-section including a flat surface.

[0142] An embodiment [4] of the present disclosure relates to at least one of the methods of embodiments [1] to [3], wherein the plurality of filaments included in the filament bundle includes at least one filament having a non-circular cross-section.

[0143] Embodiment [5] of the present disclosure relates to at least one of the methods of embodiments [1]-[4], wherein the forming includes tensioning at least one filament bundle on at least one surface.

[0144] Embodiment [6] of the present disclosure relates to at least one of the methods of embodiments [1]-[5], wherein the forming includes tensioning at least one filament bundle with at least one roller.

[0145] Embodiment [7] of the present disclosure relates to at least one of the methods of embodiments [1]-[6], wherein the forming includes tensioning at least one filament bundle in at least one curved surface such that the filaments separate from one another to form flattened fiber bands.

[0146] An embodiment [8] of the present disclosure relates to at least one of the methods of embodiments [1] to [7], wherein the forming includes tensioning at least one filament bundle with at least two rollers.

[0147] Embodiment [9] of the present disclosure relates to at least one of the methods of embodiments [1]-[8], wherein the forming includes forcing at least one filament bundle between two surfaces.

[0148] An embodiment

[10] of the present disclosure relates to at least one of the methods of embodiments [1]-[9], wherein the forming includes pressing at least one filament bundle between two rollers.

[0149] An embodiment

[11] of the present disclosure relates to at least one of the methods of embodiments [1] to

[10] , wherein the maximum diameter of the cord ranges from about 40 μm to less than about 5 mm.

[0150] An embodiment

[12] of the present disclosure relates to at least one of the methods of embodiments [1] to

[11] , wherein the maximum diameter of the core is in the range of about 20 μm to about 5 mm.

[0151] An embodiment

[13] of the present disclosure relates to at least one of the methods of embodiments [1] to

[12] , wherein the ratio of the maximum diameter of the braided sheath to the minimum diameter of the braided sheath is in the range of 1.05:1.0 to 2.5:1.0.

[0152] An embodiment

[14] of the present disclosure relates to at least one of the methods of embodiments [1] to

[13] , wherein the plurality of strands comprises at least one filament shaped strand.

[0153] An embodiment

[15] of the present disclosure relates to at least one of the methods of embodiments [1] to

[14] , wherein the filament shaped strand has a flatness factor (F) in the range of 0.05 to 0.45, wherein the flatness factor (F) is:

number

[0154] Embodiment

[16] of the present disclosure relates to at least one of the methods of embodiments [1]-

[13] and

[15] , wherein the plurality of strands includes at least one unshaped strand having a cross-sectional aspect ratio of less than 2:1.

[0155] An embodiment

[17] of the present disclosure relates to at least one of the methods of embodiments [1]-

[16] , wherein the plurality of strands includes at least one twisted strand having a twist level of greater than 0 to 1600 turns per meter.

[0156] An embodiment

[18] of the present disclosure relates to at least one of the methods of embodiments [1]-

[17] , wherein the core comprises at least two core strands twisted together at a twist level of greater than 0 to 1600 turns per meter.

[0157] An embodiment

[19] of the present disclosure relates to at least one of the methods of embodiments [1] to

[18] , wherein the core is a braided core.

[0158] Embodiment

[20] of the present disclosure relates to at least one of the methods of embodiments [1]-

[19] , wherein: the core comprises at least two core strands twisted together at a twist level of greater than 0 to 1600 turns per meter, the core is a braided core, or a combination thereof; or the plurality of strands comprises at least one unshaped strand having a cross-sectional aspect ratio of less than 2:1.

[0159] Embodiment

[21] of the present disclosure relates to at least one of the methods of embodiments [1] to

[20] , wherein the braided sheath is a triaxial braid including: angled strands having a braid angle in a relaxed state ranging from 5° to less than 90°, the angled strands including at least one filament-shaped strand; and longitudinal strands having a braid angle of less than 5° in a relaxed state.

[0160] An embodiment

[22] of the present disclosure relates to at least one of the methods of embodiments [1] to

[21] , further comprising shaping at least one longitudinal strand to form at least one shaped longitudinal strand before braiding the plurality of strands.

[0161] Embodiment

[23] of the present disclosure relates to at least one of the methods of embodiments [1]-

[22] , wherein the filament bundle further comprises a lubricant, a fiber, a surface-coated filament, or a combination thereof.

[0162] Embodiment

[24] of the present disclosure relates to at least one of the methods of embodiments [1] to

[23] , wherein the filament bundle includes at least one of a lubricating filament and a lubricating fiber.

[0163] An embodiment

[25] of the present disclosure relates to at least one of the methods of embodiments [1] to

[24] , wherein the forming is performed using at least one of a heated filament bundle and an agitated filament bundle.

[0164] An embodiment

[26] of the present disclosure relates to at least one of the methods of embodiments [1] to

[25] , wherein the surface coverage of the braided sheath on the core is at least 85%.

[0165] An embodiment

[27] of the present disclosure relates to at least one of the methods of embodiments [1] to

[26] , wherein the tensile strength of the filament shaped strand is greater than 12 cN / dtex.

[0166] An embodiment

[28] of the present disclosure relates to at least one of the methods of embodiments [1] to

[27] , wherein the braided sheath does not include synthetic fibers having a tensile strength of less than 12 cN / dtex.

[0167] An embodiment

[29] of the present disclosure relates to at least one of the methods of embodiments [1]-

[28] , wherein the pick count of the braided sheath in a relaxed state is between 30 and 3000 filament unit crossovers per meter.

[0168] An embodiment

[30] of the present disclosure relates to at least one of the methods of embodiments [1] to

[29] , wherein the number of strands (ends) of the braided sheath is 4 to 24 ends.

[0169] An embodiment

[31] of the present disclosure relates to at least one of the methods of embodiments [1] to

[30] , wherein the mass ratio of the mass of the braided sheath to the mass of the core per unit length of the cord is from about 5 / 95 to about 45 / 55.

[0170] An embodiment

[32] of the present disclosure relates to at least one of the methods of embodiments [1] to

[31] , wherein the linear mass density of the cord is from about 30 to about 10,000 denier.

[0171] An embodiment

[33] of the present disclosure relates to at least one of the methods of embodiments [1] to

[32] , wherein the linear mass density of the braided sheath is greater than the linear mass density of the core.

[0172] An embodiment

[34] of the present disclosure relates to at least one of the methods of embodiments [1]-

[33] , wherein the plurality of filaments comprises filaments having a linear mass density ranging from about 0.1 to about 30 denier.

[0173] An embodiment

[35] of the present disclosure relates to at least one of the methods of embodiments [1] to

[34] , wherein the core is a surface-treated core.

[0174] An embodiment

[36] of the present disclosure relates to at least one of the methods of embodiments [1] to

[35] , wherein the braid angle of the braided sheath in the relaxed state ranges from about 5° to about 85°.

[0175] Embodiment

[37] of the present disclosure relates to at least one of the methods of embodiments [1] to

[36] , wherein the plurality of filaments comprises at least one selected from the group consisting of liquid crystal polyester filaments, aramid filaments, copolymer aramid filaments, polyether ether ketone filaments, poly(p-phenylene benzobisoxazole) filaments, ultra-high molecular weight polyethylene filaments, high modulus polyethylene filaments, polypropylene filaments, polyethylene terephthalate filaments, polyamide filaments, polyhydroquinone diimidazopyridine filaments, and high-strength polyvinyl alcohol filaments.

[0176] Embodiment

[38] of the present disclosure relates to at least one of the methods of embodiments [1] to

[37] , wherein the plurality of filaments comprises at least two selected from the group consisting of liquid crystal polyester filaments, aramid filaments, copolymer aramid filaments, polyether ether ketone filaments, poly(p-phenylene benzobisoxazole) filaments, ultra-high molecular weight polyethylene filaments, high modulus polyethylene filaments, polypropylene filaments, polyethylene terephthalate filaments, polyamide filaments, polyhydroquinone diimidazopyridine filaments, and high-strength polyvinyl alcohol filaments.

[0177] An embodiment

[39] of the present disclosure relates to at least one of the methods of embodiments [1]-

[38] , wherein the plurality of filaments comprises copolymer aramid filaments.

[0178] Embodiment

[40] of the present disclosure relates to at least one of the methods of embodiments [1]-

[39] , wherein the plurality of filaments comprises copolyparaphenylene / 3,4'-oxydiphenylene terephthalamide filaments.

[0179] Embodiment

[41] of the present disclosure relates to at least one of the methods of embodiments [1] to

[40] , wherein the core comprises at least one selected from the group consisting of liquid crystal polyester filaments, aramid filaments, copolymer aramid filaments, polyether ether ketone filaments, poly(phenylene benzobisoxazole) filaments, ultra-high molecular weight polyethylene filaments, polypropylene filaments, high modulus polyethylene filaments, polyethylene terephthalate filaments, polyamide filaments, and high-strength polyvinyl alcohol filaments.

[0180] An embodiment

[42] of the present disclosure relates to at least one of the methods of embodiments [1] to

[41] , wherein the flattening ratio of the filament shaped strand is in the range of about 67% to about 98%.

[0181] An embodiment

[43] of the present disclosure relates to at least one of the methods of embodiments [1] to

[42] , wherein the breaking strength of the cord is at least 15 cN / dtex.

[0182] An embodiment

[44] of the present disclosure relates to a cord obtained by the method of at least one of embodiments [1] to

[43] , wherein the maximum diameter of the cord is in the range of about 40 μm to about 10 mm.

[0183] An embodiment

[45] of the present disclosure relates to a tensile member including the cord of embodiment

[44] , wherein the cord has a linear mass density of about 30 to about 10,000 denier.

[0184] An embodiment

[46] of the present disclosure relates to the tension member of embodiment

[45] , wherein the tension member is a medical cord.

[0185] An embodiment

[47] of the present disclosure relates to the tension member of at least one of embodiments

[45] and

[46] , wherein the tension member is a suture.

[0186] An embodiment

[48] of the present disclosure relates to a cord having a core-sheath structure, the cord including a core and a braided sheath of strands surrounding the core, the braided sheath including strands having a braid angle of 5° or greater in a relaxed state, wherein the strands having a braid angle of 5° or greater in a relaxed state include at least one shaped filament strand, the shaped filament strand being a no-twist strand having a twist level of less than 1 turn per meter, the cross-sectional aspect ratio of the shaped filament strand being at least 3:1 as measured at the braided sheath, the thickness of at least a portion of the braided sheath being in the range of about 20 to about 200 μm, and the braided sheath including synthetic fibers having a tensile strength greater than 12 cN / dtex.

[0187] An embodiment

[49] of the present disclosure relates to the cord of embodiment

[48] , wherein the filament shaped strands have a cross-section that includes a curved surface, the filament shaped strands have a cross-section that includes a flat surface, or a combination thereof.

[0188] An embodiment

[50] of the present disclosure relates to the cord of at least one of embodiments

[48] and

[49] , wherein the filament-shaped strands have an elliptical cross-section, the filament-shaped strands have a curved cross-section including convex portions and concave portions, or the filament-shaped strands are flat fiber bands having a cross-section including a flat surface.

[0189] An embodiment

[51] of the present disclosure relates to at least one cord of embodiments

[48] -

[50] , wherein the filament shaped strand includes at least one filament having a non-circular cross section.

[0190] An embodiment

[52] of the present disclosure relates to at least one cord of embodiments

[48] -

[51] , wherein the filament-shaped strand is formed by tensioning the filament bundle on at least one surface.

[0191] An embodiment

[53] of the present disclosure relates to at least one cord of embodiments

[48] -

[52] , wherein the filament shaped strand is formed by tensioning the filament bundle with at least one roller.

[0192] Embodiment

[54] of the present disclosure relates to at least one cord of embodiments

[48] -

[53] , wherein the filament-shaped strand is formed by tensioning the filament bundle in at least one curved surface such that the filaments separate from one another to form flattened fiber bands.

[0193] An embodiment

[55] of the present disclosure relates to at least one cord of embodiments

[48] -

[54] , wherein the filament shaped strand is formed by tensioning a filament bundle with at least two rollers.

[0194] An embodiment

[56] of the present disclosure relates to at least one cord of embodiments

[48] -

[55] , wherein the filament shaped strand is formed by forcing a bundle of filaments between two surfaces.

[0195] An embodiment

[57] of the present disclosure relates to at least one cord of embodiments

[48] -

[56] , wherein the filament shaped strand is formed by pressing a bundle of filaments between two rollers.

[0196] An embodiment

[58] of the present disclosure relates to at least one of the cords of embodiments

[48] -

[57] , wherein the maximum diameter of the cord ranges from about 40 μm to less than about 5 mm.

[0197] An embodiment

[59] of the present disclosure relates to at least one cord of embodiments

[48] -

[58] , wherein the maximum diameter of the core ranges from about 20 μm to about 5 mm.

[0198] An embodiment

[60] of the present disclosure relates to at least one cord of embodiments

[48] -

[59] , wherein the ratio of the maximum diameter of the braided sheath to the minimum diameter of the braided sheath is in the range of 1.05:1.0 to 2.5:1.0.

[0199] An embodiment

[61] of the present disclosure relates to at least one cord of embodiments

[48] -

[60] , wherein the strand having a braid angle of 5° or greater comprises at least one shaped filament strand.

[0200]

[0023] Embodiment

[62] of the present disclosure relates to at least one cord of embodiments

[48] -

[61] , wherein the filament shaped strand has a flatness factor (F) in the range of 0.05 to 0.45, wherein the flatness factor (F) is:

number

[0201] Embodiment

[63] of the present disclosure relates to at least one cord of embodiments

[48] -

[62] , wherein the braided sheath includes at least one unshaped strand having a cross-sectional aspect ratio of less than 2:1.

[0202] Embodiment

[64] of the present disclosure relates to at least one cord of embodiments

[48] -

[63] , wherein the braided sheath includes at least one twisted strand having a twist level of greater than 0 to 1600 turns per meter.

[0203] Embodiment

[65] of the present disclosure relates to at least one cord of embodiments

[48] -

[64] , wherein the core comprises at least two core strands twisted together at a twist level of greater than 0 to 1600 turns per meter.

[0204] An embodiment

[66] of the present disclosure relates to at least one cord of embodiments

[48] to

[65] , wherein the core is a braided core.

[0205] Embodiment

[67] of the present disclosure relates to at least one cord of embodiments

[48] -

[66] , wherein: the core comprises at least two core strands twisted together at a twist level of greater than 0 to 1600 turns per meter, the core is a braided core, or a combination thereof; or the braided sheath comprises at least one unshaped strand having a cross-sectional aspect ratio of less than 2:1.

[0206] An embodiment

[68] of the present disclosure relates to at least one cord of embodiments

[48] -

[67] , wherein the braided sheath further comprises longitudinal strands having a braid angle of less than 5° in a relaxed state.

[0207] Embodiment

[69] of the present disclosure relates to at least one cord of embodiments

[48] -

[68] , wherein the braided sheath further comprises longitudinal strands having a braid angle of less than 5° in a relaxed state, and the longitudinal strands comprise at least one shaped longitudinal strand having a cross-sectional aspect ratio of at least 3:1.

[0208] Embodiment

[70] of the present disclosure relates to at least one cord of embodiments

[48] -

[69] , wherein the filament shaped strand further comprises a lubricant, a fiber, a surface-coated filament, or a combination thereof.

[0209] An embodiment

[71] of the present disclosure relates to at least one cord of embodiments

[48] -

[70] , wherein the filament shaped strand comprises at least one of a lubricating filament and a lubricating fiber.

[0210] An embodiment

[72] of the present disclosure relates to at least one cord of embodiments

[48] -

[71] , wherein the surface coverage of the braided sheath on the core is at least 85%.

[0211] An embodiment

[73] of the present disclosure relates to at least one cord of embodiments

[48] -

[72] , wherein the tensile strength of the filament shaped strand is at least about 12 cN / dtex or more.

[0212] An embodiment

[74] of the present disclosure relates to at least one cord of embodiments

[48] -

[73] , wherein the braided sheath does not include synthetic fibers having a tensile strength less than 12 cN / dtex.

[0213] An embodiment

[75] of the present disclosure relates to at least one cord of embodiments

[48] -

[74] , wherein the pick count of the braided sheath in a relaxed state is between 30 and 3000 filament-unit crossovers per meter.

[0214] An embodiment

[76] of the present disclosure relates to at least one cord of embodiments

[48] to

[75] , wherein the number of strands (ends) of the braided sheath is 4 to 24 ends.

[0215] An embodiment

[77] of the present disclosure relates to at least one of the cords of embodiments

[48] to

[76] , wherein the mass ratio of the mass of the braided sheath to the mass of the core per unit length of the cord is from about 5 / 95 to about 45 / 55.

[0216] An embodiment

[78] of the present disclosure relates to at least one cord of embodiments

[48] -

[77] , wherein the cord has a linear mass density of about 30 to about 10,000 denier.

[0217] An embodiment

[79] of the present disclosure relates to the cord of at least one of embodiments

[48] to

[78] , wherein the linear mass density of the braided sheath is greater than the linear mass density of the core.

[0218] An embodiment

[80] of the present disclosure relates to at least one cord of embodiments

[48] -

[79] , wherein the filament shaped strands include filaments having a linear mass density ranging from about 0.1 to about 30 denier.

[0219] An embodiment

[81] of the present disclosure relates to at least one code of embodiments

[48] to

[80] , wherein the core is a surface-treated core.

[0220] An embodiment

[82] of the present disclosure relates to at least one cord of embodiments

[48] -

[81] , wherein the braid angle of the braided sheath in the relaxed state ranges from about 5° to about 85°.

[0221] Embodiment

[83] of the present disclosure relates to at least one cord of embodiments

[48] to

[82] , wherein the filament-shaped strand comprises at least one selected from the group consisting of liquid crystal polyester filaments, aramid filaments, copolymer aramid filaments, polyether ether ketone filaments, poly(p-phenylene benzobisoxazole) filaments, ultra-high molecular weight polyethylene filaments, high modulus polyethylene filaments, polypropylene filaments, polyethylene terephthalate filaments, polyamide filaments, polyhydroquinone diimidazopyridine filaments, and high-strength polyvinyl alcohol filaments.

[0222] Embodiment

[84] of the present disclosure relates to at least one cord of embodiments

[48] to

[83] , wherein the filament-shaped strand comprises at least two selected from the group consisting of liquid crystal polyester filaments, aramid filaments, copolymer aramid filaments, polyether ether ketone filaments, poly(p-phenylene benzobisoxazole) filaments, ultra-high molecular weight polyethylene filaments, high modulus polyethylene filaments, polypropylene filaments, polyethylene terephthalate filaments, polyamide filaments, polyhydroquinone diimidazopyridine filaments, and high-strength polyvinyl alcohol filaments.

[0223] Embodiment

[85] of the present disclosure relates to at least one cord of embodiments

[48] -

[84] , wherein the filament shaped strands comprise copolymer aramid filaments.

[0224] Embodiment

[86] of the present disclosure relates to at least one cord of embodiments

[48] -

[85] , wherein the plurality of filaments comprises copolyparaphenylene / 3,4'-oxydiphenylene terephthalamide filaments.

[0225] Embodiment

[87] of the present disclosure relates to at least one cord of embodiments

[48] -

[86] , wherein the core comprises at least one selected from the group consisting of liquid crystal polyester filaments, aramid filaments, copolymer aramid filaments, polyether ether ketone filaments, poly(phenylene benzobisoxazole) filaments, ultra-high molecular weight polyethylene filaments, polypropylene filaments, high modulus polyethylene filaments, polyethylene terephthalate filaments, polyamide filaments, and high-strength polyvinyl alcohol filaments.

[0226] An embodiment

[88] of the present disclosure relates to at least one cord of embodiments

[48] -

[87] , wherein the aspect ratio of the filament shaped strand ranges from about 67% to about 98%.

[0227] Embodiment

[89] of the present disclosure relates to at least one cord of embodiments

[48] -

[88] , wherein the cord has a breaking strength of at least 15 cN / dtex.

[0228] An embodiment

[90] of the present disclosure relates to the cord of at least one of embodiments

[48] -

[89] , wherein the maximum diameter of the cord ranges from about 40 μm to about 10 mm.

[0229] Embodiment

[91] of the present disclosure relates to a tensile member comprising at least one cord of embodiments

[48] -

[90] , wherein the cord has a linear mass density of about 30 to about 10,000 denier.

[0230] An embodiment

[92] of the present disclosure relates to the tension member of embodiment

[91] , wherein the tension member is a medical cord.

[0231] An embodiment

[93] of the present disclosure relates to the tension member of at least one of embodiments

[91] and

[92] , wherein the tension member is a suture.

[0232] The above description is presented to enable any person skilled in the art to make and use the invention, and is provided in the context of a particular application and its requirements. Various modifications to the embodiments disclosed herein will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein. In this regard, certain embodiments within the present disclosure may not represent all of the benefits of the invention, broadly considered. [Explanation of symbols]

[0233] 5 Core-sheath structure in Figures 1 and 2 10 cores 15 Braided jacket (sheath) 20 Z-Strands 25 Braided shaft 30 S-Strands 35 Braided strands overlapping protrusions 40 Distance (S) 45 Gap 50 Section plane P 55 Stiff and flattening resistant twisted S-strand 60 stiff, flattening-resistant twisted Z-strands 65 Figure 2 D max 70 D in Figure 2 min 75 The projection on one side of the braided sheath in Figure 2, where the untwisted S-strands and Z-strands overlap. 75' The projection on the opposite side of the braided sheath in Figure 2 where the S-strand and Z-strand overlap. 80 Non-overlapping S-strands on one side of the braided sheath in Figure 2 80' Non-overlapping S-strands on the opposite side of the braided sheath in Figure 2 85 Core-sheath structure in Fig. 3 90 Flat braided jacket (sheath) in Figure 3 95 S-strand in Figure 3 100 Z-strand in Figure 3 105 The small protrusion in Figure 3 110 Dmax in Figure 3 115 Dmin in Figure 3 120 A protrusion on one side of the braided sheath of FIG. 3, in which the untwisted S-strands and Z-strands overlap. 120' The projection on the opposite side of the braided sheath of FIG. 3, where the untwisted S-strands and Z-strands overlap. 125 Non-overlapping S-strands on one side of the braided sheath in Figure 3 125' Non-overlapping S-strands on the opposite side of the braided sheath in Figure 3 130 Braiding device 135 Main Enclosure 140 Career 145 Career Path 150 bobbins 155 filament bundle 160 Guide 165 Central winding shaft 170 Winding shaft moving mechanism 175 Improved Braided Carrier 180 Carrier Plate 185 Auto Adjust Swivel 190 Molding equipment 195 filament bundle 200 filament shaped strands 205 The molding device of Figure 4C 210 Roller 215 Filament Bundle 220 filament 225 filament oval shaped strand 230 Flat Fiber Band 235 Monofilaments stacked transversely across the width of the oval-shaped strand Monofilaments arranged side by side as a single layer in a flattened strand of 240 filaments 245 Filament-shaped strand with curved cross section 250 Braided Sheath 255 Right-Handed Z-Strand, shown as Strand "A" in Figure 7A 260 Right-Handed Z-Strand, Shown as Strand "C" in Figure 7A 265 The left-handed S-strand shown as strand "B" in Figure 7A 270 Left-Handed S-Strand, Shown as Strand "C" in Figure 7A 275 Optimized Braided Sheath 280 Braided shaft 285 Braid angle (θ) 290 Directional Bias 295 Distance (S) 300 strand width (W) 305 Core-sheath structure 310 twisted strands 315 Flat Braided Jacket (Sheath) 320 Untwisted S-Strand 325 Untwisted Z-Strand 330 Protrusion 335 Core-sheath structure 340 Hybrid Braided Jacket (Sheath) 345 Molded S-Strand 350 Non-Forming Z-Strand 355 Protrusion 360 Core-sheath structure with triaxial braided sheath 365 Triaxial Braided Jacket (Sheath) 370 Vertical Strands

Claims

1. Core; and a braided sheath of strands surrounding the core, the braided sheath including strands having a braid angle of 5° or more in a relaxed state; A cord having a core-sheath structure comprising: where: The strands having a braid angle of 5° or greater in a relaxed state include at least one filament-shaped strand; The filament-shaped strand is a no-twist strand having a twist level of less than 1 turn per meter; the cross-sectional aspect ratio of the filament shaped strands, measured at the braided sheath, is at least 3:1; The thickness of at least a portion of the braided sheath is in the range of 19 to 210 μm; and The cord, wherein the braided sheath comprises synthetic fibers having a tensile strength greater than 12 cN / dtex.

2. The filament shaped strand has a cross section that includes a curved surface; The filament shaped strand has a cross section that includes a plane; or The code according to claim 1, which is a combination thereof.

3. The filament shaped strand has an elliptical cross section; the filament shaped strand has a curved cross section including protrusions and depressions; or 3. The cord according to claim 1 or 2, wherein the filament-shaped strand is a flat fiber band having a cross section including a plane.

4. The cord according to any one of claims 1 to 3, wherein the filament shaped strand comprises at least one filament having a non-circular cross section.

5. The cord according to any one of claims 1 to 4, wherein the maximum diameter of the cord is in the range of 38 µm to less than 5.25 mm.

6. The cord according to any one of claims 1 to 5, wherein the maximum diameter of the core is in the range of 19 µm to 5.25 mm.

7. The cord according to any one of claims 1 to 6, wherein the ratio of the maximum diameter of the braided sheath to the minimum diameter of the braided sheath is in the range of 1.05:1.0 to 2.5:1.

0.

8. The cord according to any one of claims 1 to 7, wherein the strand having a braid angle of 5° or more is made up of at least one filament shaped strand.

9. The filament shaped strand has a flatness factor (F) in the range of 0.05 to 0.45, where F is the flatness factor: [Equation 1] [In the formula, D ｍａｘ is the maximum diameter of the braided sheath in micrometers (μm), measured in a cross-sectional plane of the cord that is perpendicular to the longitudinal axis of the cord; D ｍｉｎ is the minimum diameter of the braided sheath in micrometers (μm), measured in a cross-sectional plane of the cord that is perpendicular to the longitudinal axis of the cord; and D ｓ is the minimum diameter of the filament bundle before forming, in micrometers (μm), measured in a cross-sectional plane of the filament bundle that is perpendicular to the longitudinal axis of the filament bundle. The code according to any one of claims 1 to 8, wherein

10. The cord of any one of claims 1 to 9, wherein the braided sheath comprises at least one unshaped strand having a cross-sectional aspect ratio of less than 2:

1.

11. The cord according to any one of claims 1 to 10, wherein the braided sheath comprises at least one twisted strand having a twist level of from greater than 0 to 1600 turns per metre.

12. The cord according to any one of claims 1 to 11, wherein the core comprises at least two core strands twisted together at a twist level of from greater than 0 to 1600 turns per metre.

13. The cord according to any one of claims 1 to 12, wherein the core is a braided core.

14. The cord according to any one of claims 1 to 13, wherein the tensile strength of the filament shaped strand is at least 11.4 cN / dtex or more.

15. The cord according to any one of claims 1 to 14, wherein the mass ratio of the mass of the braided sheath to the mass of the core per unit length of the cord is 5 / 95 to 45 / 55.

16. The cord according to any one of claims 1 to 15, wherein the filament-shaped strand comprises at least one selected from the group consisting of liquid crystal polyester filaments, aramid filaments, copolymer aramid filaments, polyether ether ketone filaments, poly(p-phenylene benzobisoxazole) filaments, ultra-high molecular weight polyethylene filaments, high-modulus polyethylene filaments, polypropylene filaments, polyethylene terephthalate filaments, polyamide filaments, polyhydroquinone diimidazopyridine filaments, and high-strength polyvinyl alcohol filaments.

17. The cord according to any one of claims 1 to 16, wherein the core comprises at least one selected from the group consisting of liquid crystal polyester filaments, aramid filaments, copolymer aramid filaments, polyether ether ketone filaments, poly(phenylene benzobisoxazole) filaments, ultra-high molecular weight polyethylene filaments, polypropylene filaments, high modulus polyethylene filaments, polyethylene terephthalate filaments, polyamide filaments, and high-strength polyvinyl alcohol filaments.

18. A tension member comprising the cord of any one of claims 1 to 17, wherein the cord has a linear mass density of 28.5 to 10,500 denier.

19. 20. The tension member of claim 18, wherein the tension member is a medical cord.

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