WO2024072537A1

WO2024072537A1 - Edge seal coating for metal armoring tape

Info

Publication number: WO2024072537A1
Application number: PCT/US2023/028544
Authority: WO
Inventors: Eddy R. Houston; Jason N. MORROW
Original assignee: Commscope Technologies Llc
Priority date: 2022-09-30
Filing date: 2023-07-25
Publication date: 2024-04-04

Abstract

An armoring or shielding layer for a communication cable is primarily formed of an elongated strip of conductive material having a first side and an opposite, second side. As provided to the cable manufacturing facility on a reel, the first and second sides of the elongated strip of conductive material may be bare and exposed surfaces, or one or both of the first and second sides may include a mono-layer to allow for controlled jacket bonding, such as polypropylene. During cable manufacturing, a strip of adhesive material, such as a copolymer of ethylene acrylic acid (EAA) may be applied to the first side proximate a first side edge, the second side proximate a second side edge, or both. The armoring or shielding layer is wrapped around a cable core to form an overlapped portion at the first and second edges and adhered to itself to seal the cable core.

Description

EDGE SEAL COATING FOR METAL ARMORING TAPE

BACKGROUND OF THE INVENTION

1. Field of the Invention

[001] The present invention generally relates to a shielding or armoring layer for a communication cable. More particularly, the present invention relates to a coating and/or adhesive pattern to be employed on a metallic, shielding or armoring layer.

2. Description of the Background

[002] Shielding and armoring layers for communication cables are well known in the art. With electrical communication cables an encircling metallic shielding layer can prevent electromagnetic interference (EMI) from entering or exiting the cable. An encircling armoring layer is also made of a metal and is often corrugated for added strength. The armoring layer can provide crush resistance, rodent chew-though protection and water ingress protection for a communication cable. Such protections are needed for optical communication cables, where EMI is not an issue, and may also be useful for some electrical and hybrid cables, where the armoring layer may simultaneously serve the functions of crush resistance, rodent protections and EMI shielding.

[003] FIGS. 1 and 2 show a typical shielded twisted pair cable 1 including a first twisted pair A, a second twisted pair B, a third twisted pair C and a fourth twisted pair D. A dielectric isolator 3 separates twisted pair A from twisted pairs B, C and D, separates twisted pair B from twisted pairs C and D, and also separates twisted pair C from twisted pair D. The isolator 3 may also be referred to as a flute, star-shaped separator or plus-shaped separator.

[004] The twisted pairs A, B, C and D in combination with the isolator 3 may be twisted in the direction of arrow 5 (e.g., opposite to the twist direction of the twisted pairs A, B, C and D) to form a stranded core. The stranded core is surrounded by a shielding layer 7. The shielding layer 7 may be formed of a conductive foil, and the foil's edges may partially overlap at area 9. A dielectric outer jacket 11 then surrounds the shielding layer 7. [005] FIG. 3 shows a fiber optic cable 8, having many buffer tubes 17 and/or filler rods 21 bundled together, as is known in the prior art. The fiber optic cable 8 has a six-around-one configuration, wherein six buffer tubes 17 and/or filler rods 21 are located around a central strength member 25. In FIG. 3, reference numeral 10 denotes an outer jacket. The outer jacket 10 surrounds an armoring layer 13. The armoring layer 13 surrounds a cable core 15 and has an overlapped portion 14.

[006] In practice, the cable core 15 is made up of separate cabling elements, such as one or more buffer tubes 17 with loose optical fibers 19 and/or one or more filler rods 21 and/or one or more insulated power conductors. FIG. 3 shows a six-around-one configuration, or more precisely six cable elements around the central strength member 25. The strength member 25 may be formed as a glass-reinforced plastic (GRP) rod or a fiber-reinforced plastic (FRP) rod. First and second binding tapes 35 and 37 wrap around the cable core 15 to hold the core 15 together as the armoring layer 13 and jacket 10 are applied. Commonly, the first and second binding tapes 35 and 37 are made of flat, polyester tape.

[007] As shown in the perspective view of FIG. 4, the armoring layer 13, prior to being corrugated, is formed as a flat, elongated strip of material having a with W. Typical values for the width W are greater than 25 mm, such as 50 mm, 101mm, 152 mm and 203 mm. The armoring layer 13 arrives at the manufacturing factory on a reel in a length exceeding 1,000 meters, such as 1,500 to 2,500 meters.

[008] The FIG. 5 is a cross sectional view taken along line V— V in FIG. 4, which is not to scale but demonstrates a thickness of several coating layers residing on the armoring layer 13. An overall thickness t of the armoring layer 13 is about 0.22 to 0.40 mm, such as 0.27 mm. A substrate thickness S of the central metallic layer 41 is about 0.12 to 0.25 mm, such as approximately 0.15 mm Typically, the metallic layer 41 is formed of a corrosion resistant metal, such as electrolytically chrome-coated steel (ECCS).

[009] A first copolymer coating on a top of the metallic layer 41 is known as a first coextrusion (COEX) layer and comprises two or more different resins extruded one atop the other into a sandwich-like film with distinguishable individual layers. One or more of the films may be colored by a tint, and a green tint is common in the cabling art. The simultaneous co-extrusion of two or more resins layered together produces a film which has improved strength and puncture and scratch resistance and also allows different resins to have different functions, such that an outer resin may be removed to reveal an inner resin, with different characteristics, e.g., more adhesive in nature than the outer resin. A COEX layer is distinguishable from a mono-extrusion wherein a single resin is extruded onto the metallic layer 41.

[010] A first thickness tl of the first COEX layer is about 0.010 to 0.015 mm, such as 0.013 mm. The top-most layer 43 is typically formed of polypropylene, or some other non-tacky or non-adhesive type of material . A first intermediate layer 45 between the top-most layer 43 and the metallic layer 41 is typically formed of a copolymer of ethylene and acrylic acid (EAA), or some other type of tacky or much more adhesive substance as compared to polypropylene. EAA’s ionic nature allows for excellent adhesive bonding to metal foils and other surfaces.

[011] A second copolymer coating on a bottom of the metallic layer 41 is known as a second COEX layer and comprises two or more different resins extruded one atop the other into a sandwich-like film with distinguishable individual layers. A second thickness t2 of the second COEX layer is about 0.010 to 0.015 mm, such as 0.013 mm, and may be formed like the first COEX layer. The bottom-most layer 47 is typically formed of polypropylene, or some other non- tacky or non-stick type of polymer. A second intermediate layer 49 between the bottom-most layer 47 and the metallic layer 41 is typically formed of a copolymer of EAA, or some other type of tacky or adhesive substance.

[012] During manufacturing, the armoring layer 13 is corrugated before being wrapped around the cable core 15. The corrugations increase the crush resistance of the armoring layer 13. The armoring layer 13 has the overlapped portion 14, which is preferably sealed. Sealing the armoring layer 13 back onto itself at the overlapped portion 14 creates a moisture barrier in case a rodent, e g., bird, squirrel or rat, chews through portions of the jacket 10, or in case the jacket 10 is slightly tom during installation.

[013] The sealing operation includes applying a heat source, via a flame or flames, to one or both of the edges of the armoring layer to be sealed together at the overlapped portion 14. The flame burns off or melts away a strip of the top-most layer 43 and/or the bottom-most layer 47, e.g., the polypropylene layer, to expose the first intermediate layer 45 and/or the second intermediate layer 49, e.g., the EAA layer. Once, the strip of EAA is exposed by the flame, the EAA will function to adhere and seal the armoring layer 13 back onto itself at the overlapped portion 14.

[014] The remaining top-most layer 43, formed of polypropylene or some other nonadhesive compound, is the surface of the armoring layer 13 contacting the inside surface of the jacket 10 as the jacket 10 is extruded over the armoring layer 13. This interface produces what is known as a controlled jacket bond (CJB). The hot, extruded jacket material is bonded to the topmost layer 43 to produce a water-resistant seal. However, the extent of bonding is controlled so that the jacket 10 can be cleanly peeled off of the armoring layer 13 during a termination or midspan access.

[015] The remaining bottom-most layer 47, formed of polypropylene or some other nonadhesive compound, is the surface of the armoring layer 13 contacting the cable core 15. The hot, extruded jacket material may cause the armoring layer 13 to become hot itself and bond the bottom-most layer 47 to one or more of the elements of the cable core 15. The bottom -most layer 47, which is formed of polypropylene or another non-adhesive material, will assist in keeping the armoring layer 13 from sticking to the elements of the cable core 15 so that the armoring layer 13 can be cleanly peeled off of the cable core 15 during a termination or mid-span access.

SUMMARY OF THE INVENTION

[016] The applicant has appreciated drawbacks with the armoring layer 13 of the prior art and the method by which the armoring layer 13 is adhered back onto itself at the overlapped portion 14. It is an object of the present invention to address one or more of the appreciated drawbacks.

[017] A basic disadvantage in the prior art is the added cost to fully coat both sides of the metallic layer 41 with the first and second COEX layers when the functions of the coatings are not needed on all surface areas of the metallic layer 41. For example, an adhesive layer is only needed at the overlapped portion 14. The top-most and bottom-most polypropylene layers 43 and 47 may not be needed (except to cover the adhesive layer). In the case of many fiber optic cables 8, the elements of the cable core 15 will not stick to the bare metallic layer 41 at all, or at least to any extent as to hinder a termination or mid-span access. For example, buffer tubes 17 are typically formed of polypropylene which does not adhere to the bare metallic layer 41 to any extent which would cause damage to the buffer tubes 17 or hinder a termination or midspan access.

[018] Moreover, the first and second COEX layers produce smoke and gases when burned, and an armoring layer with less coatings will produce less smoke and gases when burned Therefore, the cable is more likely to pass a required smoke and noxious gases test for a particular use or standard.

[019] Another important drawback is that the flame method of removing the top-most and/or bottom-most layers 43 and 47 to expose the adhesive, first and/or second intermediate layers 45 and 49 is not 100% accurate in removing a uniform and even strip of the top-most layer 43 and/or the bottom-most layer 47. Sometimes excessive EAA is exposed on the inside surface of the armoring layer 13 facing the cable core 15, beyond the overlapped portion 14. The EAA will tend to adhere the armoring layer 13 to the cable components, e g., the buffer tubes 17, which will make a termination or mid-span access more difficult.

[020] Also, the flame applied to the bottom-most layer 47 of the armoring layer 13 to expose the EAA for the overlap 14 can make the polypropylene on the top-most layer 43 of the armoring layer 13 melt to expose a portion of EAA on the outside surface of the armoring layer 13 facing to the jacketing material. If the polypropylene of the top-most layer 43 is not present, a controlled jacket bond (CJB) is not fully achieved. The areas where the EAA of the armoring layer 13 contact the jacketing material may cause the armoring layer 13 to stick to the jacket 10 proximate the overlap 14, which makes it more difficult to remove the jacket 10 from the armoring layer 13 for a termination or mid-span access. Also, water ingress between the jacketing layer and the armoring layer may be compromised because there was a lack of controlled jack bonding (CJB) at points where the top-most layer 43 was inadvertently melted/removed due to the flame method of removing the layers 43 and 47.

[021] To address these and other drawbacks, the present invention provides a new armoring layer and a new method of adhering and sealing the overlapped portion 14 of the armoring layer. The principals of the present invention may also be applicable to the creation of a new shielding layer and a new method of forming the overlap 7 of the shielding layer, which may be beneficial for EMI shielding in an electrical cable, e.g., a twisted pair cable or a coaxial cable.

[022] These and other objects are accomplished by an armoring or shielding layer for a communication cable, which is primarily formed of an elongated strip of conductive material having a first side and an opposite, second side As provided to the cable manufacturing facility on a reel, the first and second sides of the elongated strip of conductive material may be bare and exposed surfaces, or one or both of the first and second sides may include a mono-layer to allow for controlled jacket bonding, such as polypropylene. During cable manufacturing, a strip of adhesive material, such as a copolymer of ethylene acrylic acid (EAA) may be applied to the first side proximate a first side edge, the second side proximate a second side edge, or both. The armoring or shielding layer is wrapped around a cable core to form an overlapped portion at the first and second edges and adhered to itself to seal the cable core.

[023] Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

[024] For a better understanding of the invention, and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which:

[025] FIG. 1 is a perspective view of a shielded, twisted pair cable, in accordance with the prior art;

[026] FIG. 2 is a cross sectional view taken along line II-II in FIG. 1;

[027] FIG. 3 is a perspective view of a fiber optic cable end with a portion of an outer jacket and an armoring layer removed to show the elements of the cable core, in accordance with the prior art; [028] FIG. 4 is a perspective view of an end of a flat armoring layer prior to corrugation, in accordance with the prior art;

[029] FIG. 5 is a cross sectional view taken along line V— V in FIG. 4;

[030] FIG. 6 is a perspective view of an end of a flat armoring layer prior to corrugation, in accordance with the present invention;

[031] FIG. 7 is a cross sectional view taken along line A— A in FIG. 6, illustrating a first embodiment of the present invention;

[032] FIG. 8 is a cross sectional view taken along line A— A in FIG. 6, illustrating a second embodiment of the present invention;

[033] FIG. 9 is a cross sectional view taken along line A- A in FIG. 6, illustrating a third embodiment of the present invention;

[034] FIG. 10 is a cross sectional view taken along line A— A in FIG. 6, illustrating a fourth embodiment of the present invention;

[035] FIG. 11 is a cross sectional view taken along line A— A in FIG. 6, illustrating a fifth embodiment of the present invention;

[036] FIG. 12 is a perspective view of a fiber optic cable end with a portion of an outer jacket and a portion of an armoring layer removed to show the elements of the cable core, in accordance with the present invention; and

[037] FIG. 13 is a flowchart illustrating a method of making a communication cable in accordance with the present invention.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

[038] The present invention now is described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. [039] Like numbers refer to like elements throughout. In the figures, the thickness of certain lines, layers, components, elements or features may be exaggerated for clarity. Broken lines illustrate optional features or operations unless specified otherwise.

[040] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the specification and relevant art and should not be interpreted in an idealized or overly formal sense unless expressly so defined herein. Well-known functions or constructions may not be described in detail for brevity and/or clarity.

[041] As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items. As used herein, phrases such as "between X and Y" and "between about X and Y" should be interpreted to include X and Y. As used herein, phrases such as "between about X and Y" mean "between about X and about Y." As used herein, phrases such as "from about X to Y" mean "from about X to about Y."

[042] It will be understood that when an element is referred to as being "on", "attached" to, "connected" to, "coupled" with, "contacting", etc., another element, it can be directly on, attached to, connected to, coupled with or contacting the other element or intervening elements may also be present. In contrast, when an element is referred to as being, for example, "directly on", "directly attached" to, "directly connected" to, "directly coupled" with or "directly contacting" another element, there are no intervening elements present. It will also be appreciated by those of skill in the art that references to a structure or feature that is disposed "adjacent" another feature may have portions that overlap or underlie the adjacent feature.

[043] Spatially relative terms, such as “under”, “below”, “lower”, “over”, “upper”, “lateral”, “left”, “right” and the like, may be used herein for ease of description to describe one element or feature’s relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is inverted, elements described as “under” or “beneath” other elements or features would then be oriented “over” the other elements or features. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the descriptors of relative spatial relationships used herein interpreted accordingly.

[044] FIG. 6 is a perspective view of an end of an armoring layer 51 prior to corrugation or a shielding layer 51, in accordance with the present invention. The armoring layer 51 is generally similar in its outer appearance to the armoring layer 13 prior to corrugation, as shown in the prior art of FIG. 4. However, the armoring layer 51 prior to corrugation (or a shielding layer 51) may have a thinner overall thickness and a different layering structure in cross section. FIG. 7 is a cross sectional view taken along line A— A in FIG. 6, illustrating a first embodiment of the present invention.

[045] In FIGS. 6 and 7, an elongated strip of conductive material 53 has a first side 55 and an opposite, second side 57. The first side 55 is substantially planar, and the second side 57 is substantially planar and parallel to the first side 55. A thickness S of the elongated strip of conductive material 53 is defined as a distance between the first and second sides 55 and 57, along a line, which is perpendicular to both of the first and second sides 55 and 57. The thickness S is between 0.10 mm to 0.30 mm, more preferably about 0.12 to 0.25 mm, such as approximately 0.15 mm.

[046] A width W of the elongated strip of conductive material 53 extends between a first side edge 59 and a second side edge 61. As will be described in greater detail below, the width W is sufficient in dimension to wrap around a cable core and overlap back onto itself. Typical values for the width W are greater than 10 mm and less than 550 mm, such as 25 mm, 50 mm, 101 mm, 152 mm and 203 mm. The armoring layer 51 arrives at the manufacturing factory with an overall length L exceeding 1,000 meters, such as 1,500 to 3,000 meters and is stored on a reel.

[047] The elongated strip of conductive material 53 is formed of a corrosion resistant metal. In a preferred embodiment, the corrosion resistant metal is electrolytically chrome-coated steel (ECCS), however other corrosion resistant metals, such as aluminum and/or stainless steel may be used.

[048] A first layer 63 is formed of a mono-extrusion polymer. The first layer 63 is applied directly onto an entirety of the first side 55 of the elongated strip of conductive material 53. The first layer 63 forms a first exposed surface 65 of the armoring or shielding layer 51. The first layer 63 is much thinner than the thickness S of the elongated strip of conductive material 53, and may have a thickness of less than 0.07 mm, such as less than 0.05 mm, or about 0.01 mm to 0.04 mm. The mono-extrusion polymer may include polypropylene, so as to form a controlled jacket bond (CJB) with a material of a jacket 10 of the communication cable 50, as shown in FIG. 12.

[049] The second side 57 of the elongated strip of conductive material 53 forms a second exposed surface 67 of the armoring or shielding layer 51, as fed into the cable manufacturing equipment. Typically, the armoring or shielding layer 51 is wound onto a reel with the first exposed surface 65 contacting the second exposed surface 67 to form a spiral on the reel. The armoring or shielding layer 51 is paid off of the reel and into the cable manufacturing equipment.

[050] In FIG. 7, an adhesive material 69, which is much more adhesive than the monoextrusion polymer material forming the first layer 63, is applied to a first portion 71 of the first layer 63 on the first exposed surface 65. In a preferred embodiment, the adhesive material 69 is formed of a copolymer of ethylene acrylic acid (EAA). Other adhesives may also be used to adhere, bond and/or seal the armoring or shielding layer 51 back to itself at overlapped portions OP when the second exposed surface 67 near the second side edge 61 is overlapped on top of the first exposed surface 65 near the first side edge 59.

[051] The first portion 71 is proximate to the first side edge 59 of the elongated strip of conductive material 53. However, in a preferred embodiment, there is a first gap 73 where no adhesive is applied between the first portion 71 and the first side edge 59. Likewise, there is a second gap 75, where no adhesive is applied, on the opposite side of the first portion 71 within the overlapped portion OP.

[052] FIG. 12 shows a communication cable 50 produced by the cable manufacturing equipment and specifically the overlapped portion OP when the armoring layer 51 surrounds the cable core 15. The armoring layer 51 has been corrugated by the cable manufacturing equipment to have annular ridges and valleys extending between the first and second side edges 59 and 61. The cable core 15 may include the elements as outlined in the background section in relation to FIG. 3, including first and second buffer tubes 17 and at least one optical fiber 19 contained within each of the first and second buffer tubes 17.

[053] The first gap 73 within the overlapped portion OP will help to keep adhesive material 69 from escaping past the first side edge 59. Such escaped adhesive material 69 could contact with one or more elements 17, 21, 35 and/or37 of the cable core 15 and cause an adherence between the armoring layer 51 and one or more elements 7, 21, 35 and/or 37 of the cable core 15. The second gap 75 will help to keep adhesive material 69 from escaping outside of the overlapped portion OP and being present on the first exposed surface 65. Such escaped adhesive material 69 would contact the extruded jacket 10 and could interfere with the controlled jacket bond (CJB) and make the separation of the armoring layer 51 from the jacket 10 more difficult.

[054] FIG. 8 is a cross sectional view taken along line A— A in FIG. 6, illustrating a second embodiment of the present invention. The second embodiment illustrates that the adhesive material 69 may be placed on a second portion 77 of the second exposed surface 67 of the armoring or shielding layer 51 A. The adhesive material 69 is used to adhere, bond and/or seal the armoring or shielding layer 51 A back to itself at the overlapped portions OP when the second exposed surface 67 near the second side edge 61 is overlapped on top of the first exposed surface 65 near the first side edge 59.

[055] Like a mirror image of the embodiment of FIG. 7, the second portion 77 is proximate to the second side edge 61 of the elongated strip of conductive material 53. Similarly, there is a third gap 79 where no adhesive is applied between the second portion 77 and the second side edge 61. Likewise, there is a fourth gap 81, where no adhesive is applied, on the opposite side of the second portion 77 within the overlapped portion OP. [056] FIG. 9 is a cross sectional view taken along line A— A in FIG. 6, illustrating a third embodiment of the present invention. The third embodiment illustrates that the adhesive material 69 may be placed on both the first portion 71 of the first exposed surface 65 and the second portion 77 of the second exposed surface 67 of the armoring or shielding layer 5 IB. The adhesive material 69 is used to adhere, bond and/or seal the armoring or shielding layer 5 IB back to itself at the overlapped portions OP when the second exposed surface 67 near the second side edge 61 is overlapped on top of the first exposed surface 65 near the first side edge 59.

[057] Like the embodiments of FIGS. 7 and 8, the first, second, third and fourth gaps 73, 75, 79 and 81 exist where no adhesive is applied. The first, second, third and fourth gaps 73, 75, 79 and 81 assist in preventing adhesive material 69 from escaping outside of the overlapped portions OP, when the second exposed surface 67 near the second side edge 61 is overlapped on top of the first exposed surface 65 near the first side edge 59.

[058] FIG. 10 is a cross sectional view taken along line A— A in FIG. 6, illustrating a fourth embodiment of the present invention. The only difference between the fourth embodiment and the first through third embodiments of FIGS. 7-9 is that the first layer 63 formed of a monoextrusion polymer is not present. Now, the first exposed surface 65A of the armoring or shielding layer 51C is formed by the first side 55 of the elongated strip of conductive material 53. The second exposed surface 67 is still formed by the second side 57 of the elongated strip of conductive material 53.

[059] The fourth embodiment of FIG. 10 would be useful in a situation where the extruded material used form the jacket 10 forms a controlled jacket bond (CJB) with, yet does not excessively stick to, the first side 55 of the elongated strip of conductive material 53. The jacket 10 is typically formed of medium-density or high-density polyethylene. Under such circumstances, the armoring or shielding layer 51 will typically benefit from the first layer 63 formed of a mono-extrusion polymer, e.g., polypropylene. However, some jackets 10 may be formed of other materials like nylon and certain specialty materials for producing zero halogen under burning conditions. In these instances, it may be possible to eliminate the need to cover the first side 55 of the elongated strip of conductive material 53 with the first layer 63, e.g., polypropylene. [060] FIG. 11 is a cross sectional view taken along line A— A in FIG. 6, illustrating a fifth embodiment of the present invention. The only difference between the fifth embodiment and the first through third embodiments of FIGS. 7-9 is that a second layer 83 formed of the monoextrusion polymer, e.g., polypropylene, has been applied to the second side 57 of the elongated strip of conductive material 53. Now, the second exposed surface 67A of the armoring or shielding layer 5 ID is formed by the second layer 83. The first exposed surface 65 is still formed by the first layer 63.

[061] The fifth embodiment of FIG. 11 would be useful in a situation where the elements 17, 21, 35 and 37 of the cable core 15 tend to stick to the second side 57 of the elongated strip of conductive material 53. In the embodiments shown in FIGS. 7-10, as the jacket 10 is the extruded onto the armoring or shielding layer 5 ID, the heat can transfer through the elongated strip of conductive material 53 and heat the elements 17, 21, 35 and 37 of the cable core 15 and cause them to adhere to the second side 57 of the elongated strip of conductive material 53. Typically, this is not an issue with buffer tubes 17 since the buffer tubes 17 are formed of polypropylene. However, some cable cores 15 may include insulated conductors, e.g., a hybrid cable, or other specialty components for a particular use, e.g., a jacketed coaxial cable. These elements may tend to adhere to the second side 57 of the elongated strip of conductive material 53, which could complicate a mid-span access or termination of the cable 50.

[062] In the fourth and fifth embodiments of FIGS. 10 and 11, the adhesive material 69 is applied to at least one of the first portion 71 and the second portion 77, as taught in the description of FIGS 7-9. It is also worth noting that if the elements 17, 21, 35 and 37 of the cable core 15 tend to stick to the elongated strip of conductive material 53, while the material of the jacket 10 does not need the first layer 63 to achieve a good CJB and prevent sticking, then the armoring or shielding layer 51 , 51 A, 5 IB of FIGS. 7-9 may be flipped such that the second side 57 of the elongated strip of conductive material 53 contacts the jacket 10, while the first layer 63 contacts the cable core 15.

[063] FIG. 13 is a flowchart illustrating a method of making a communication cable 50 in accordance with the present invention. The method includes paying SI 01 an elongated strip of material 51, 51A, 51B, 51C, 51D having a first exposed side 65, 65A and an opposite, second exposed side 67, 67A, and a width W defined between a first side edge 59 and a second side edge 61, into a cable forming machine.

[064] The method continues with corrugating SI 03 the elongated strip of material 51, 51A, 51B, 51C, 51D. The corrugating S103 may include forming annular ridges and valleys extending between the first and second side edges 59 and 61. Next, the method continues with engaging SI 05 a cable core 15 against the second exposed side 67, 67A of the elongated strip of material 51, 51 A, 5 IB, 51C, 5 ID, between the first and second sides edges 59 and 61 and bringing S 107 at least one of the first and second side edges 59 and 61 of the elongated strip of material 51 , 51 A, 5 IB, 51C, 5 ID around the cable core 15.

[065] An optional operation of heating SI 09 one or both of first and second facing portions 71 and 77 of the first and second exposed sides 65, 65 A and 67, 67A at an overlapped portion OP may be included in the method. The heating SI 09 may be included to remove or soften any layer on the elongated strip of material 51, 51 A, 5 IB, 51C, 5 ID.

[066] The method continues with applying Si l l an adhesive material 69 to one or both of the facing first and second portions 71 and 77. The first and second side edges 59 and 61 are brought past each other as the cable core 15 is surrounded, causing an overlapping SI 13 to form an overlapped portion OP where the first and second portions 71 and 77 face each other.

[067] Then, the method continues with adhering SI 15 the elongated strip of material 51, 51A, 5 IB, 51C, 5 ID to itself at the overlapped portion OP. Finally, the operation finishes with extruding SI 17 a jacket 10 over the elongated strip of material 51, 51A, 51B, 51C, 51D after the adhering SI 15 of the elongated strip of material 51, 51A, 51B, 51C, 51D to itself at the overlapped portion OP.

[068] It should be noted that the applying Si l l of the adhesive material 69 may occur prior to the bringing SI 07 at least one of the first and second edges 59 and 61 of the elongated strip of material 51, 51A, 51B, 51C, 51D around the cable core 15. Further, adhering SI 15 the elongated strip of material 51, 51A, 51B, 51C, 51D to itself at the overlapped portion OP may include sealing the elongated strip of material 51, 51A, 51B, 51C, 51D to itself at the overlapped portion OP to prevent water infiltration. [069] As previously mentioned, the structures and methods described herein offer several advantages such as a reduction in material costs, as an EAA adhesive is not deployed over an entirety of the armoring or shielding layer 51. The reduction in material can lead to less produced smoke and gases when burned and assist a cable in passing a required smoke and noxious gases test for a particular use or standard. The application of a narrow strip of adhesive can be more precise than the structures and methods of the prior art, where a flame can overexpose an EAA layer and complicate the mid-span access and termination of a cable. Also, the overall thickness T3 and T4 of the embodiments of the armoring or shielding layer 51, 51A, 51B, 51C, 51D of the present invention are all thinner than the thickness t of the armoring layer 13 of the prior art shown in FIG. 5. Hence, a longer length of the armoring or shielding layer 51, 51A, 51B, 51C, 51D of the present invention can fit onto a currently-used reel for the cable manufacturing equipment.

[070] The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.

Claims

We claim:

1. An armoring or shielding layer for a communication cable comprising: an elongated strip of conductive material having a first side and an opposite, second side, and a width defined between a first side edge and a second side edge, where said width is sufficient to wrap around a cable core and overlap back onto itself; a first layer formed of an extruded polymer, wherein said first layer is applied directly onto an entirety of said first side of said elongated strip of conductive material and forms a first exposed surface of said armoring or shielding layer, as fed into cable manufacturing equipment, and wherein said second side of said elongated strip of conductive material forms a second exposed surface of said armoring or shielding layer, as fed into the cable manufacturing equipment; and an adhesive material, which is more adhesive than said extruded polymer, wherein said adhesive material is applied to at least one of: a first portion on said first exposed surface of said armoring or shielding layer proximate said first side edge of said elongated strip of conductive material; and a second portion on said second exposed surface of said armoring or shielding layer proximate said second side edge of said elongated strip of conductive material.

2. An armoring or shielding layer for a communication cable comprising: an elongated strip of conductive material having a first side and an opposite, second side, and a width defined between a first side edge and a second side edge, where said width is sufficient to wrap around a cable core and overlap back onto itself; a first layer formed of a first extruded polymer, wherein said first layer is applied directly onto an entirety of said first side of said elongated strip of conductive material and forms a first exposed surface of said armoring or shielding layer, as fed into cable manufacturing equipment; a second layer formed of a second extruded polymer, wherein said second layer is applied directly onto an entirety of said second side of said elongated strip of conductive material and forms a second exposed surface of said armoring or shielding layer, as fed into cable manufacturing equipment; and an adhesive material, which is more adhesive than said mono-extrusion polymer, wherein said adhesive material is applied to at least one of: a first portion on said first exposed surface of said armoring or shielding layer proximate said first side edge of said elongated strip of conductive material; and a second portion on said second exposed surface of said armoring or shielding layer proximate said second side edge of said elongated strip of conductive material.

3. An armoring or shielding layer for a communication cable comprising: an elongated strip of conductive material having a first side and an opposite, second side, and a width defined between a first side edge and a second side edge, where said width is sufficient to wrap around a cable core and overlap back onto itself, wherein said first side of said elongated strip of conductive material forms a first exposed surface of said armoring or shielding layer, as fed into cable manufacturing equipment, and wherein said second side of said elongated strip of conductive material forms a second exposed surface of said armoring or shielding layer, as fed into the cable manufacturing equipment; and an adhesive material, wherein said adhesive material is applied to at least one of: a first portion on said first exposed surface of said armoring or shielding layer proximate said first side edge of said elongated strip of conductive material; and a second portion on said second exposed surface of said armoring or shielding layer proximate said second side edge of said elongated strip of conductive material.

4. The armoring or shielding layer according to any one of claims 1 or 2, wherein said extruded polymer is a mono-extrusion of polypropylene.

5. The armoring or shielding layer according to any one of claims 1, 2 or 3, wherein said adhesive material is formed of a copolymer of ethylene acrylic acid.

6. The armoring or shielding layer according to any one of claims 1, 2 or 3, wherein said width is between 10 and 550 mm.

7. The armoring or shielding layer according to any one of claims 1, 2 or 3, wherein said conductive material is formed of a corrosion resistant metal.

8. The armoring or shielding layer according to claim 7, wherein said corrosion resistant metal is electrolytically chrome-coated steel (ECCS).

9. The armoring or shielding layer according to any one of claims 1, 2 or 3, wherein said first side is substantially planar, wherein said second side is substantially planar and is parallel to said first side, and wherein a thickness of said elongated strip of conductive material is defined as a distance between said first and second sides along a line which intersects said first side and said second side perpendicularly.

10. The armoring or shielding layer according to claim 9, wherein said thickness of said elongated strip of conductive material is between 0.10 mm to 0.30 mm.

11. The armoring or shielding layer according to any one of claims 1, 2 or 3, wherein a gap exists on said first and/or second exposed surfaces and said adhesive material, such that said adhesive material is not applied immediately adjacent to said first and/or second side edges.

12. A communication cable comprising: a cable core including first and second buffer tubes and at least one optical fiber contained within each of said first and second buffer tubes; and an armoring layer according to one of claims 1 , 2 or 3 surrounding said cable core

13. The communication cable according to claim 12, wherein said armoring layer is corrugated to have annular ridges and valleys extending between said first and second side edges of said elongated strip of conductive material.

14. A method of making a communication cable comprising: paying an elongated strip of material, having a first exposed side and an opposite, second exposed side, and a width defined between a first side edge and a second side edge, into cable manufacturing equipment; engaging a cable core against the second exposed side of the elongated strip of material, between the first and second sides edges; bringing at least one of the first and second side edges of the elongated strip of material around the cable core; overlapping the first and second side edges to form an overlapped portion of the elongated strip of material; applying an adhesive material to one or both of facing first and second portions of the first and second exposed sides at the overlapped portion; adhering the elongated strip of material to itself at the overlapped portion; and extruding a jacket over the elongated strip of material after said adhering the elongated strip of material to itself at the overlapped portion.

15. The method according to claim 14, wherein said applying the adhesive material occurs prior to said bringing at least one of the first and second edges of the elongated strip of material around the cable core.

16. The method according to claim 14, wherein said adhering the elongated strip of material to itself at the overlapped portion incudes sealing the elongated strip of material to itself at the overlapped portion.

17. The method according to claim 14, further comprising: heating one or both of the first and second facing portions of the first and second exposed sides at the overlapped portion, wherein said heating occurs prior to said applying the adhesive material.

18. The method according to claim 14, wherein the first and second portions are distanced from the first and second side edges.

19. The method according to claim 14, further comprising: corrugating the elongated strip of material prior to said extruding a jacket over the elongated strip of material.

20. The method according to claim 19, wherein said corrugating includes forming annular ridges and valleys extending between the first and second side edges.