Armored cable with improved crush resistance

Abstract

Embodiments of the disclosure relate to an optical fiber cable. The optical fiber cable includes an outer jacket defining a central bore extending along a longitudinal axis of the optical fiber cable. An armor layer is disposed within the first central bore and defines a second central bore extending along the longitudinal axis. A plurality of buffer tubes are disposed within the second central bore. Bedding is disposed between the plurality of buffer tubes and the armor layer. In some embodiments, a binder layer is disposed within the armor layer.

Description

Attorney Docket No.: HI24-045PCTARMORED CABLE WITH IMPROVED CRUSH RESISTANCECROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of priority of U.S. Provisional Application No. 63 / 723,154, filed on November 21, 2024, the content of which is relied upon and incorporated herein by reference in its entirety.BACKGROUND

[0002] The disclosure relates generally to optical fiber cables and, in particular, to optical fiber cables with improved crush resistance and flame-retardant performance. Optical fiber cables are deployed in a variety of different operating environments, including aerial, subterranean, underwater, and over the ground. The optical fiber cable must be configured to withstand the conditions of its respective environment. This can involve exposure to extreme temperature (hot or cold), tensile forces, crush forces, corrosive agents, rodents, fire, and weather, among others. The cable construction can vary to account for the conditions to which the optical fiber cable is exposed with the general goal of maintaining optical transmission despite being subjected to the harshest conditions of that environment, even if such conditions may be rare.SUMMARY

[0003] According to an aspect, embodiments of the disclosure relate to an optical fiber cable. The optical fiber cable includes a jacket with an interior surface and an exterior surface. The interior surface defines a central bore extending along a longitudinal axis of the optical fiber cable. The exterior surface defines an outermost surface of the optical fiber cable. The optical fiber cable includes a plurality of buffer tubes disposed in the central bore, each buffer tube of the plurality of buffer tubes contains at least one optical fiber. The optical fiber cable includes an armor layer and a bedding compound. The armor layer includes at least one corrugation and is disposed in the central bore between the plurality of buffer tubes and the interior surface. The bedding compound surrounds the plurality of buffer tubes and is positioned between the plurality of buffer tubes and the corrugated armor layer. The bedding compound at least partially fills a space defined by the at least one corrugation.

[0004] In another aspect, embodiments of the disclosure relate to an optical fiber cable. The optical fiber cable includes a jacket with an interior surface and an exterior surface. TheAttorney Docket No.: HI24-045PCT interior surface defines a central bore extending along a longitudinal axis of the optical fiber cable. The optical fiber cable includes a plurality of buffer tubes disposed in the central bore, each buffer tube of the plurality of buffer tubes contains at least one optical fiber. The optical fiber cable further includes an armor layer, a bedding compound, and a binder film. The armor layer includes at least one corrugation and is disposed in the central bore between the plurality of buffer tubes and the interior surface. The bedding compound surrounds the plurality of buffer tubes and is positioned between the plurality of buffer tubes and the corrugated armor layer. The binder film surrounds the plurality of buffer tubes and has a thickness less than 0.5 mm.

[0005] In another aspect, embodiments of the disclosure relate to an optical fiber cable. The optical fiber cable includes a cable core. The cable core includes at least one optical fiber disposed within a buffer tube and a bedding compound surrounding the buffer tube. The optical fiber cable includes a flame-retardant cable jacket surrounding the cable core. The cable jacket includes a multilayered structure including a first layer and a second layer surrounding the first layer. The first layer includes an interior surface and an exterior surface. The interior surface defines a central bore extending along a length of the optical fiber cable. The exterior surface defines an outermost surface of the cable jacket. The optical fiber cable further includes a binder and an armor layer. The binder surrounds the cable core and is disposed within the central bore defined by the first layer. The armor layer is positioned between the interior surface of the first layer and the binder film.

[0006] Additional features and advantages will be set forth in the detailed description that follows, and in part will be readily apparent to those skilled in the art from the description or recognized by practicing the embodiments as described in the written description and claims hereof, as well as the appended drawings.

[0007] It is to be understood that both the foregoing general description and the following detailed description are merely exemplary, and are intended to provide an overview or framework to understand the nature and character of the claims.

[0008] The accompanying drawings are included to provide a further understanding and are incorporated in and constitute a part of this specification. The drawings illustrate one or more embodiment(s), and together with the description serve to explain principles and the operation of the various embodiments.Attorney Docket No.: HI24-045PCTBRIEF DESCRIPTION OF THE DRAWINGS

[0009] FIG. 1 is a perspective view of an optical fiber cable according to an exemplary embodiment.

[0010] FIG. 2 is a front perspective view of the cable of FIG. 1 according to an exemplary embodiment.

[0011] FIG. 3 is a detailed perspective view of steel tape for an optical cable, according to an exemplary embodiment.

[0012] FIG. 4 is a cross-sectional view of an optical fiber cable, according to an exemplary embodiment.DETAILED DESCRIPTION

[0013] Referring generally to the figures, various embodiments of an optical fiber cable with improved crush performance and good flame-retardant performance are provided. As will be discussed in greater detail below, in one or more embodiments, the optical fiber cable includes an armor layer, such as steel tape, with bedding around a core of the cable. In one or more embodiments, the armor layer is corrugated and the bedding will fill in areas between the corrugations such that during a crush event, the bedding between the corrugations and / or around the cable core will resist the force on the optical fiber cable. Furthermore, because the bedding provides water blocking, water blocking tape, threads and / or yarns may not be utilized in certain embodiments of the optical fiber cable. The disclosed optical fiber cable including the bedding compound has fewer components available for burning than various existing optical fiber cables, and particularly, the removal of water blocking components that are formed of polyester improves flame-retardant performance. Additionally, bedding with desirable burn properties can be chosen to improve both crush performance and the flameretardant performance of the optical fiber cable.

[0014] In one or more embodiments, the optical fiber cable includes a core with bedding positioned around buffer tubes, which buffer tubes may be surrounded by a thin film binder. In such embodiments, the bedding can fill in and be pressed into corrugations of the armor layer. In one or more embodiments, the thin film binder is a flame-retardant thin film binder. In one or more embodiments, the optical fiber cable includes one or more stranded tube layers with bedding surrounding the buffer tubes. Exemplary embodiments of the opticalAttorney Docket No.: HI24-045PCT fiber cable(s) with improved crush and flame-retardant performance will be described in greater detail below and in relation to the figures provided herewith, and these exemplary embodiments are provided by way of illustration, and not by way of limitation.

[0015] FIGS. 1-2 depict an example embodiment of an optical fiber cable 10. The optical fiber cable 10 includes a cable jacket 12 having an inner surface that defines a bore. Disposed within the cable jacket 12 is an armor layer 14. In one or more embodiments, the armor layer 14 is a metal tape. In one or more embodiments, armor layer 14 is steel tape. In one or more embodiments, armor layer 14 has corrugations 16.

[0016] A cable core 20 is disposed within the bore of the cable jacket 12. The armor layer 14 is formed around the cable core 20 and between the cable core 20 and the cable jacket 12, so that the armor layer 14 protects the cable core 20 from damage due to external forces acting on the cable jacket 12. Disposed within the core 20 are one or more optical fibers 24. In one or more embodiments, including the embodiment of FIG. 1, the optical fibers 24 are contained within buffer tubes 22. In one or more embodiments the optical fibers 24 are in a loose tube configuration within the buffer tubes 22. In various embodiments, the buffer tubes 22 are stranded in one or more layers around a central strength member. In one or more embodiments, each buffer tube 22 contains an optical fiber 24 in a tightly buffered configuration. In still further embodiments, each buffer tube 22 can contain a plurality of optical fibers arranged in an intermittently-bonded optical fiber ribbon. In yet further embodiments, the buffer tubes 22 may be omitted from the cable 10, and the cable 10 can instead have loose fibers 24 disposed therein. In still further embodiments, the optical fibers 24 can be disposed in thin-film polymeric binders (not shown) that, like the buffer tubes 22, surround groups of the optical fibers 24 to facilitate distinguishing the groups of optical fibers 24 from one another. However, unlike the buffer tubes 22, the thin-film polymeric binders are capable of deforming in response to stresses on the cable 10, allowing the fibers 24 to shift to lower-stress positions within the cable 10 while maintaining a high fiber density in the cable 10.

[0017] In various embodiments, cable jacket 12 may comprise or be formed of any of a variety of materials such as, but not limited to, polyethylene (e.g., high, medium, or low density polyethylene), polyvinyl chloride (PVC), polyvinylidene difluoride (PVDF), nylon, polyester or polycarbonate and their copolymers. In addition, the material of the cable jacket 12 may include small quantities of other materials or fillers that provide different propertiesAttorney Docket No.: HI24-045PCT to the material of the cable jacket 12. For example, the material of the cable jacket 12 may include materials that provide for coloring, UV / light resistance (e.g., carbon black), burn resistance, etc.

[0018] In one or more embodiments, cable jacket 12 includes one or more intumescent materials or flame-retardant materials. In an exemplary embodiment, cable jacket 12 comprises a flame-retardant non-corrosive (FRNC) material or low-smoke zero-halogen (LSZH) material. In such embodiments, the cable jacket 12 is formed from a material that includes a polymer component and at least one of an intumescent material (such as, but not limited to, ammonium polyphosphate (APP), intumescent graphite, or triazine) or a flameretardant additive (such as, but not limited to, alumina trihydrate (ATH) or magnesium dihydroxide (MDH)).

[0019] In one or more embodiments, a bedding compound 18 is disposed within the core 20 and at least partially between the core 20 and the armor layer 14. For example, and as shown in FIGs. 1 and 2, in embodiments wherein the cable 10 includes buffer tubes 22, the bedding compound 18 can be disposed between the buffer tubes 22 and the armor layer 14. In one or more embodiments, bedding compound 18 is positioned around buffer tubes 22 in interstitial spaces between the buffer tubes 22. In one or more embodiments, bedding compound 18 fills substantially an entire area between the buffer tubes 22 and a central strength member around which the buffer tubes 22 are arranged. In one or more embodiments, bedding compound 18 at least partially fills corrugations 16 of armor layer 14. In one or more embodiments, bedding compound 18 entirely fills the corrugations 16 of the armor layer 14. Stated differently, a surface of the layer of bedding compound 18 can be substantially conformal to an inside surface profile of the armor layer 14. As is referenced below, the bedding compound 18 is relatively soft, and once the bedding compound 18 is extruded about the core 20 (e.g., around the buffer tubes 22) it remains deformable. Accordingly, when the armor layer 14 is formed around the core 20, the corrugations 16 of the armor layer 14 deform the bedding compound 18, causing the bedding compound 18 to at least partially conform to the shape of the corrugations 16.

[0020] FIG. 3 depicts a detailed example embodiment of armor layer 14 that can be utilized with optical fiber cable 10. In one or more embodiments, the armor layer 14 has a plurality of corrugations 16. A distance between a first edge 28 and a second edge 30 of a corrugation 16 defines a height, H. In one or more embodiments, H is about 0.45 mm. In one or moreAttorney Docket No.: HI24-045PCT embodiments, H is about 0.60 mm. In one or more embodiments, H is between 0.3 mm and 0.78 mm.

[0021] As previously discussed, Applicant believes the use of bedding compound 18 discussed herein, provides improved crush performance, and improved flame-retardant performance of the optical fiber cable 10 due to the position and material properties of bedding compound 18. When a force, such as a crushing force, is placed on optical fiber cable 10, bedding compound 18 provides resistance against deflection of the armor layer 14. Therefore, a greater crushing force is required to press or deform optical fiber cable 10. As will be generally understood, as optical fiber cables are pressed or bent, buffer tubes may collapse and cause signal attenuation. Applicant surmises the use of the bedding compound 18 between the armor layer 14 and a remainder of the cable core 20 distributes the loads on the optical cable 10 to reduce signal attenuation.

[0022] In one or more embodiments, bedding compound 18 is formed from a soft material. In one or more embodiments, bedding compound 18 has a Shore A hardness between 60 and 80 and more specifically a Shore A hardness between 70 and 80 measured according to ISO 7619-1. In one or more embodiments, bedding compound has a Shore A hardness of about 74 measured according to ISO 7619-1. As will be generally understood, the softness of bedding compound 18 means bedding compound 18 deforms easily and therefore absorbs energy generated by a crushing force. Furthermore, the inventors surmise the use of bedding compound 18 in combination with armor layer 14 improves bending and torsion performance of the optical cable.

[0023] In one or more embodiments, bedding compound 18 is formed from greater than 80% inorganic component(s) and less than 20% of organic component(s). In one or more embodiments, bedding compound 18 is formed from greater than 80% flame-retardant filler and less than 20% of polymer, such as thermoplastic olefin elastomer. By way of example, the bedding compound 18 comprises the material FM 0474 / 5 (available from Melos GmbH, Melle, Germany).

[0024] In one or more embodiments, the Young’s modulus of bedding compound 18 decreases with increasing temperature.

[0025] In one or more embodiments, bedding compound 18 has a relatively low viscosity, where viscosity is defined as the resistance of a polymer to flow. In one or moreAttorney Docket No.: HI24-045PCT embodiments, bedding compound 18 has a Mooney viscosity between 20 to 40 MU and more specifically between 25 and 35 MU measured at 100 degrees Celsius. In one or more embodiments, bedding compound 18 has a Mooney viscosity of about 32 MU measured at 100 degrees Celsius. Mooney viscosity is measured according to ISO 289-1.

[0026] As will be generally understood, density is defined as mass divided by volume, expressed as g / cm3. In one or more embodiments, bedding compound 18 has a density of about 1.82 g / cm3measured according to ISO 1183-1A. Limiting oxygen index (LOI) describes the minimum oxygen concentration of an oxygen / nitrogen atmosphere needed to sustain a “candle light” flame burning on a sample and indicates the degree of flame retardancy. In one or more embodiments, bedding compound 18 has an LOI between 40% and 80%, more specifically between 55% and 75%. In one or more embodiments, bedding compound 18 has an LOI of about 63% measured according to ASTM D 2863 A.

[0027] In one or more embodiments, bedding compound 18 has a relatively low coefficient of thermal expansion (CTE). In one or more embodiments, bedding compound 18 has a CTE less than 200 pm / m° C, specifically less than 150 pm / m° C, and more specifically less than 130 pm / m°C. In one or more embodiments, bedding compound 18 has a CTE of about 123.6 pm / m°C (e.g., about 123.6 pm / m°C plus or minus 0.8 °C).

[0028] In one or more embodiments, bedding compound 18 does not increase the thickness of optical fiber cable 10. In other words, bedding compound 18 fills in spaces within cable 10 (e.g., between and around the buffer tubes 22) without increasing the outer diameter of optical fiber cable 10. In one or more embodiments, bedding compound 18 is utilized with optical fiber cable 10 and forms a layer that is disposed between the buffer tubes 22 and the armor layer 14. In such embodiments, the bedding compound 18 may increase the thickness or outer diameter of optical fiber cable 10 (relative to a similarly configured cable having the bedding compound 18 omitted).

[0029] In one or more embodiments, optical fiber cable 10 is formed using two extruders. In one or more embodiments, a first extruder is used to apply the bedding compound 18 (e.g., around a stranded bundle of the buffer tubes 22). The armor layer 14 may then be formed around the bedding compound, and a second extruder used to apply cable jacket 12 around the armor layer 14. In one or more embodiments, tandem extrusion is used to apply theAttorney Docket No.: HI24-045PCT bedding compound 18 over and around the buffer tubes 22 and then to apply the cable jacket 12 after the armor layer 14 has been formed around the bedding compound 18.

[0030] FIG. 4 depicts another example embodiment of an optical fiber cable 100. The optical fiber cable 100 includes a jacket 112 having an interior surface 114 that defines a bore, shown as central bore 118. The optical fiber cable 100 includes a cable core 120 that is disposed within the central bore 118. Jacket 112 further includes an exterior surface 116. In one or more embodiments, exterior surface 116 defines an outermost surface of optical fiber cable 100. In one or more embodiments, optical fiber cable 100 optionally includes an outer layer 134 disposed on exterior surface 116. As will be generally understood, such an outer layer 134 is configured to facilitate deployment of optical fiber cable 100. For example, the outer layer 134 can be formed from a low-friction material to facilitate air jetting of the optical fiber cable 100.

[0031] In one or more embodiments, the cable core 120 can include anywhere from one to several hundred or even thousands of optical fibers 126. Further, the optical fibers 126 may be in a loose tube or ribbon configuration within buffer tubes 124. In various embodiments, the buffer tubes 124 may be stranded around a central strength member 122. The strength member 122 may be configured as a dielectric strength member, for example an up jacketed glass-reinforced composite rod. In other embodiments, the strength member 122 may be, or may include, a steel rod, a stranded steel wire, tensile yarn or fibers, for example bundled aramid, or other strengthening materials. Still further, the optical fibers 126 may be divided into other subunit structures, such as grouped within binding films or thin membranes 128.

[0032] In one or more embodiments, the cable 100 has a multilayered jacket structure. In one or more embodiments, cable core 120 includes an internal jacket structure. In one or more embodiments, cable core 120 and optical fibers 126 are surrounded by a multi-layered cable jacket that comprises a first layer (see e.g., jacket 112) and at least a second layer 110 disposed within the first layer 112. In one or more embodiments, at least one of first layer 112 and second layer 110 includes at least one flame-retardant additive. In one or more embodiments, the flame-retardant additives include at least one of an intumescent-acting material and a filler material and a gas-phase active material and a condensed-phase active material. In one or more embodiments, the density of the intumescent-acting material is lower than 1.2 g / cm3. In one or more embodiments, the density of the mineral-based flame-Attorney Docket No.: HI24-045PCT retardant compound can be above 1.3 g / cm3 due to the filler. In one or more embodiments, the mineral filler material is between 40 and 65 wt % of the layer material.

[0033] In one or more embodiments, the intumescent-acting material may include a phosphorous-nitrogen combination or ammonium polyphosphate (APP) or intumescent graphite or triazine or combinations thereof. In one or more embodiments, ATH or MDH may be used as possible metal hydrate filler materials or metal hydroxide filler materials. In one or more embodiments, Boehmite (AMH) may be used a possible metal hydroxide filler material. Metal oxide hydroxide filler materials decompose at higher temperature compared to the corresponding hydroxides. Thus, by using metal hydroxides and / or metal oxide hydroxide, the decomposition temperature of the mineral filler can be controlled.

[0034] In one or more embodiments, two stranded layers of buffer tubes 124 are disposed within second layer 110. In such embodiments, a third layer of stranded buffer tubes 124 are positioned between second layer 110 and first layer 112. In one or more embodiments, a bedding compound 130 is disposed within the second layer 110. In other words, bedding compound 130 is positioned within second layer 110 around buffer tubes 124. In one or more embodiments, bedding compound 130 is disposed within first layer 112 and between first layer 112 and second layer 110 around buffer tubes 124. In one or more embodiments, bedding compound 130 is disposed within first layer 110 and second layer 112.

[0035] In one or more embodiments, optical fiber cable 100 includes a thin film binder 128 surrounding the cable core 120 and positioned between jacket 112 and cable core 120. In one or more embodiments, optical fiber cable 100 includes thin film binder 128 and an armor layer 132, with the armor layer positioned between first layer 112 and thin film binder 128. In one or more embodiments, armor layer 132 is steel tape. In one or more embodiments, armor layer 132 is low carbon electrolytic chrome coated steel tape. In one or more embodiments, armor layer 132 includes corrugations. In one or more embodiments, armor layer 132 has an interior surface and an exterior surface. In one or more embodiments, armor layer 132 has a coating on the exterior surface. In one or more embodiments, armor layer 132 has a coating on the interior surface. In one or more embodiments, armor layer 132 has a coating on the exterior surface and the interior surface. In one or more embodiments, the coating on the armor layer 132 is a copolymer. In one or more specific embodiments, the coating is an ethylene acrylic acid copolymer (EAA).Attorney Docket No.: HI24-045PCT

[0036] In one or more embodiments, thin film binder 128 has a thickness less than 0.5 mm, specifically less than 0.2 mm or less, and more specifically less than 0.15 mm. In one or more embodiments, thin film binder 128 has a thickness between 0.05 mm and 0.15 mm. In one or more embodiments, thin film binder 128 has a thickness between 0.5 mm and 1.0 mm.

[0037] In one or more embodiments, thin film binder 128 is a flame-retardant thin film binder. In one or more embodiments, thin film binder 128 includes flame-retardant additives. In one or more embodiments, film binder 128 is not a flame-retardant binder. In one or more embodiments, binder 128 is formed from a polymeric material such as polyethylene (e.g., low-density polyethylene, medium-density polyethylene, high-density polyethylene), polypropylene, polyurethane, etc. In one or more embodiments, binder 128 includes at least 70% by weight polyethylene and may include stabilizers, nucleation initiators, fillers, fire- retardant additives, fiberglass fibers and / or other reinforcement elements.

[0038] Applicant believes the thin film binder 128 still allows for pressing of bedding compound 130 into corrugations on armor layer 132. Therefore, in one or more embodiments, bedding compound 130 entirely fills corrugations on armor layer 132. In one or more embodiments, bedding compound 130 at least partially fills corrugations on armor layer 132.

[0039] Unless otherwise expressly stated, it is in no way intended that any method set forth herein be construed as requiring that its steps be performed in a specific order. Accordingly, where a method claim does not actually recite an order to be followed by its steps or it is not otherwise specifically stated in the claims or descriptions that the steps are to be limited to a specific order, it is in no way intended that any particular order be inferred. In addition, as used herein, the article "a" is intended to include one or more than one component or element, and is not intended to be construed as meaning only one.

[0040] It will be apparent to those skilled in the art that various modifications and variations can be made without departing from the spirit or scope of the disclosed embodiments. Since modifications, combinations, sub-combinations and variations of the disclosed embodiments incorporating the spirit and substance of the embodiments may occur to persons skilled in the art, the disclosed embodiments should be construed to include everything within the scope of the appended claims and their equivalents.

Claims

Attorney Docket No.: HI24-045PCTWhat is claimed is:

1. An optical fiber cable, comprising: a jacket comprising: an interior surface, the interior surface defining a central bore extending along a longitudinal axis of the optical fiber cable; and an exterior surface, the exterior surface defining an outermost surface of the optical fiber cable; a plurality of buffer tubes disposed in the central bore, each buffer tube of the plurality of buffer tubes containing at least one optical fiber; an armor layer comprising at least one corrugation, the armor layer disposed in the central bore between the plurality of buffer tubes and the interior surface; and a bedding compound surrounding the plurality of buffer tubes and positioned between the plurality of buffer tubes and the armor layer, wherein the bedding compound at least partially fills a space defined by the at least one corrugation.

2. The optical fiber cable of claim 1, wherein the bedding compound has a Shore A hardness between 60 and 80.

3. The optical fiber cable of claim 1, wherein the armor layer comprises a steel tape.

4. The optical fiber cable of claim 1, wherein the bedding compound comprises more than 80% flame-retardant filler and less than 20% polymer.

5. The optical fiber cable of claim 1, wherein the bedding compound entirely fills a space defined by the at least one corrugation.

6. The optical fiber cable of claim 1, wherein the bedding compound has a Mooney viscosity between 20 to 40 MU at 100 °C.

7. The optical fiber cable of claim 1, wherein the bedding compound has a coefficient of thermal expansion less than 150 pm / m°C.Attorney Docket No.: HI24-045PCT8. The optical fiber cable of claim 1, wherein the bedding compound has a limiting oxygen index between 55% and 75%.

9. The optical fiber cable of claim 1, wherein the armor layer further comprises an interior surface and an exterior surface, and wherein the armor layer includes a coating on at least one of the interior surface and the exterior surface.

10. An optical fiber cable, comprising: a jacket comprising: an interior surface, the interior surface defining a central bore extending along a longitudinal axis of the optical fiber cable; and an exterior surface; a plurality of buffer tubes disposed in the central bore, each buffer tube of the plurality of buffer tubes containing at least one optical fiber; an armor layer comprising at least one corrugation, the armor layer disposed in the central bore between the plurality of buffer tubes and the interior surface of the jacket; a bedding compound surrounding the plurality of buffer tubes and positioned between the plurality of buffer tubes and the armor layer; and a binder film surrounding the plurality of buffer tubes, the binder film having a thickness less than 0.5 mm.

11. The optical fiber cable of claim 10, wherein the bedding compound at least partially fills a space defined by the at least one corrugation.

12. The optical fiber cable of claim 10, further comprising a central strength member, and wherein the plurality of buffer tubes are stranded around the central strength member.

13. The optical fiber cable of claim 12, wherein the bedding compound fills substantially an entire area between the plurality of buffer tubes and the central strength member.

14. The optical fiber cable of claim 13, wherein the bedding compound fills substantially an entire space between the plurality of buffer tubes and the binder film.Attorney Docket No.: HI24-045PCT15. The optical fiber cable of claim 10, wherein the binder film comprises flame-retardant additives.

16. The optical fiber cable of claim 10, wherein the bedding compound has a Shore A hardness between 70 and 80 and wherein the bedding compound has a coefficient of thermal expansion less than 150 pm / m°C.

17. An optical fiber cable, comprising: a cable core comprising: a buffer tube; at least one optical fiber disposed within the buffer tube; and a bedding compound surrounding the buffer tube; a flame-retardant cable jacket surrounding the cable core, wherein the cable jacket comprises a multilayered structure comprising: a first layer comprising: an interior surface, the interior surface defining a central bore extending along a length of the optical fiber cable; and an exterior surface defining an outermost surface of the cable jacket; and a second layer surrounded by the first layer; a binder surrounding the cable core and disposed within the central bore defined by the first layer; and an armor layer positioned between the interior surface of the first layer and the binder.

18. The optical fiber cable of claim 17, wherein the buffer tube is a first buffer tube, wherein the cable core comprises: a plurality of buffer tubes that includes the first buffer tube, each of the plurality of buffer tubes having at least one optical fiber disposed therein; and a strength member, wherein the plurality of buffer tubes are positioned around the strength member, and wherein the bedding compound is positioned in a space around the plurality buffer tubes.

19. The optical fiber cable of claim 18, wherein the cable core further comprises a second plurality of buffer tubes each having at least one optical fiber disposed therein, the secondAttorney Docket No.: HI24-045PCT plurality of buffer tubes positioned between the first layer and the second layer of the cable jacket, and wherein the second plurality of buffer tubes are surrounded by the bedding compound.

20. The optical fiber cable of claim 17, wherein the armor layer is a steel tape.

21. The optical fiber cable of claim 17, wherein the binder is a flame-retardant binder.

22. The optical fiber cable of claim 17, wherein the binder is a film having a thickness less than 0.2 mm.

23. The optical fiber cable of claim 17, wherein the cable jacket includes a flameretardant additive that includes at least one of: an intumescent-acting material; a filler materi l, a gas-phase active material, or a condensed-phase active material.

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