Abstract: A cable of this invention includes a core comprising a plurality of coated optical fibers and a filling composition of matter that is disposed about the fibers. Typically, the fibers and the filling material are disposed within a tubular member that is disposed within a sheath system. The sheath system includes longitudinally extending strength members and a plastic jacket. The filling composition that fills interstices in the core is one that includes an oil constituent that is a relatively high molecular weight aliphatic hydrocarbon. A relatively small percent by weight of a stereochemically hindered antioxidant system is used to prevent thermal oxidative degradation of the filling material as well as of materials in contact with the filling material. Such stereochemically hindered antioxidants will not migrate out of filling material into other cable and fiber materials, thereby increasing their effectiveness.

Abstract: A buffer encasement has a longitudinally extending interior surface that extends around and defines a longitudinally extending passage containing a stack of optical fiber ribbons. The interior surface closely bounds the stack, and the buffer encasement is easily removable from the stack. The buffer encasement can be is easily removable from the stack because the buffer encasement is thin and is constructed of a material that is capable of being easily torn. The buffer encasement can be is easily removable from the stack because the buffer encasement defines a longitudinally extending weakened portion that is capable of being more easily torn than the remainder of the buffer encasement. The weakened portion is operative so that when the weakened portion is torn the buffer encasement defines longitudinally extending edges on the opposite sides of the tear. The edges can be separated from one another to define an opening therebetween through which the stack of optical fiber ribbons can be accessed.

Abstract: A buffer encasement has a longitudinally extending interior surface that extends around and defines a longitudinally extending passage containing a stack of optical fiber ribbons. The interior surface closely bounds the stack, and the buffer encasement is easily removable from the stack. The buffer encasement can be is easily removable from the stack because the buffer encasement is thin and is constructed of a material that is capable of being easily torn. The buffer encasement can be is easily removable from the stack because the buffer encasement defines a longitudinally extending weakened portion that is capable of being more easily torn than the remainder of the buffer encasement. The weakened portion is operative so that when the weakened portion is torn the buffer encasement defines longitudinally extending edges on the opposite sides of the tear. The edges can be separated from one another to define an opening therebetween through which the stack of optical fiber ribbons can be accessed.

Abstract: An optical fiber cable having a core which includes at least one optical fiber transmission medium, a sheath system which is disposed about said core, and a filling material disposed within said core. The filling material of the optical fiber cable includes both a hydrocarbon carrier means, and a thickening system disposed within the hydrocarbon carrier means. The thickening system may include an inorganic constituent, either alumina or fumed alumina, and a polymer.

Abstract: An optical module includes a stack of optical fiber ribbons that are within a buffer encasement, such as a thin sheath, that closely bounds the periphery of the stack. The optical modules can be rectangular, so that the optical modules can be readily stacked in a manner that results in a very space efficient fiber optic cable. The optical modules can be tested prior to being incorporated into the fiber optic cable so as to maximize the probability of the fiber optic cable being fully operable. The sheath cushions all of the sides of the stack. In some optical modules, the stack is movable relative to the sheath and the optical fiber ribbons are movable relative to one another.

Abstract: A fiber optic cable includes multiple differently sized stacks of optical fiber ribbons. The stacks include a central stack that is approximately centrally located in a jacket passage and peripheral stacks positioned radially around the central stack. A difference exists between the dimensions of the central stack and the dimensions of one or more of the peripheral stacks. Another fiber optic cable has multiple longitudinally extending stacks of optical fiber ribbons that are within a jacket passage. The stacks include a central stack that is approximately centrally located in the jacket passage, and peripheral stacks positioned radially around the central stack. Buffer encasements that respectively contain the peripheral stacks are longitudinally stranded around the central stack.

Abstract: A family of lubricants for use in fabricating optical fiber cables having stacked optical fiber ribbons is disclosed. Each of the lubricants, is characterized by a surface tension less than 34 dynes per centimeter, a contact angle of less than 44 degrees and a viscosity appropriate for the cabling application.

Abstract: A stack of optical fiber ribbons is enclosed in a buffer encasement having a relatively soft inner portion and an relatively hard outer portion. The inner portion has an interior surface extends around and defines a longitudinally extending passage that contains the stack, and the interior surface closely bounds the stack. The outer portion extends around, closely bounds and contacts the inner portion, and has a modulus of elasticity that is greater than the modulus of elasticity of the inner portion. In accordance with one example of the invention, the inner portion has an exterior surface that extends around and is spaced apart from the passage, and the outer portion has an interior surface that extends around, closely bounds, and engages the exterior surface of the inner portion, whereby the buffer encasement has multiple plies. In contrast, in accordance with another example of the invention, a surface is not defined between the inner portion and the outer portion.

Abstract: An optical cable [100] having one or more optical fibers [11] that are surrounded by an improved filling material [10] is disclosed. The filling material includes one or more synthetic oil(s) that are present in an amount, which is 80 to 95 percent by weight of the filling material and which have an average molecular weight that is greater than about 350. The filling material further includes an organic gelling agent, which is a diblock copolymer that is present in an amount of about 5 to 20 percent by weight. However, no more than 1.5 percent by weight of inorganic gelling agents may be used without impairing the long-term stability of the viscosity and the yield stress of the filling material. Preferably, a blend of two different polyalphaolefin oils are used while inorganic gel ling agents are completely avoided. Critical-yield stress is kept appropriately low (i.e., less than 0.01 psi) by the use of diblock copolymers.

Abstract: A cable 20 of this invention includes at least one core 22 comprising a plurality of coated optical fibers 25 and a filling material 26 which is disposed about the fibers 25. Typically, the fibers 25 and the filling material 26 are disposed within a tubular member 28 which is disposed within a sheath system 27. The sheath system 27 may include longitudinally extending strength members 30 in addition to a plastic jacket 32. The filling material made in accordance with the preferred embodiment of the present invention is one which comprises at least two different hydrocarbons as an oil constituent and/or two different fumed silicas as part of a thickening agent. The hydrocarbon(s) may be a synthetic oil such as polyalphaolefin, for example, or a mineral oil, or a combination of synthetic oils and/or mineral oils. The combination of oils is used to help low temperatures properties as well as better incorporate a gelling system which may include a copolymer. A copolymer is used mainly to reduce oil separation.