Abstract: A single-mode transmission optical fibre includes a central core region radially outwardly from a centerline to a radius r1 and having a positive relative refractive index ?1; a first inner cladding region extending radially outwardly from the central core to a radius r2 and having a negative relative refractive index ?2; a second inner cladding region extending radially outwardly from the first inner cladding region to a radius r3 and having a non-negative relative refractive index ?3; an intermediate cladding region extending radially outwardly from the second inner cladding region to a radius r4 having a negative relative refractive index ?4 larger in absolute value than the relative refractive index ?2; and an outer cladding region extending radially outwardly from the intermediate cladding region and having a non-negative relative refractive index ?5; wherein the relative refractive index ?2 of the first inner cladding region is ?0.1·10?3 to ?1.

Abstract: An optical fiber includes an optical waveguide, a first coating layer disposed to surround the optical waveguide and a second coating layer disposed to surround the first coating layer, wherein the first coating layer is formed by a cured polymeric material obtained by curing a radiation curable composition including at least one (meth)acrylate monomer esterified with at least one branched alcohol having from 9 to 12 carbon atoms, and the second coating layer is formed by a cured polymeric material obtained by curing a radiation curable (meth)acrylate composition including from 0.8% to 1.5% by weight of silica, based on the total weight of the composition.

Abstract: An optical fiber includes a glass core and a protective coating consisting of a single coating layer disposed to surround the glass core, wherein the single coating layer is formed from a cured polymeric material obtained by curing a radiation curable composition including: (i) a radiation curable urethane(meth)acrylate oligomer, preferably including a backbone derived from polyoxytetramethylene glycol, (ii) at least one monofunctional reactive monomer, (iii) at least one multifunctional reactive monomer, and (iv) an adhesion promoter.

Abstract: An apparatus for coloring optical fibers, includes: a first reservoir for containing a natural coating material to be applied onto an optical fiber being drawn; a second reservoir for containing a colorant to be mixed with the natural coating material; a mixer in fluid communication with the first and second reservoirs to receive a first flow of natural coating material and a second flow of colorant and to mix the first and second flows to obtain a colored coating material; a coating die in fluid communication with the mixer to receive the flow of colored coating material and to apply it onto the optical fiber being drawn.

Abstract: An optical fiber having: a) a glass portion; and b) at least one protective coating layer disposed to surround the glass portion, the protective coating layer having a modulus of elasticity value between ?40° C. and +60° C. between 5 MPa and 600 MPa, preferably not higher than 500 MPa, more preferably not higher than 450 MPa and much more preferably not higher than 300. Preferably the protective coating layer is a single protective coating layer which is disposed in contact with the glass portion.

Abstract: The present invention relates to a radiation curable coating composition comprising a radiation curable oligomer comprising a backbone derived from polypropylene glycol and a dimer acid based polyester polyol, wherein said coating composition, when cured, is having: a) a hardening temperature (Th) of from ?10° C. to about ?20° C. and a modulus measured at said Th of lower than 5.0 MPa; or b) a hardening temperature (Th) of from ?20° C. to about ?30° C. and a modulus measured at said Th of lower than 20.0 MPa; or c) a hardening temperature (Th) of lower than about ?30° C. and a modulus measured at said Th of lower than 70.0 MPa.

Abstract: An optical fiber having an internal glass portion, a first coating layer surrounding the glass portion and a second coating layer surrounding the first coating layer. The first coating layer is formed from a cured polymeric material obtained by curing a radiation curable composition having a radiation curable oligomer having a backbone derived from polypropylene glycol and a dimer acid based polyester polyol. The cured polymeric material has: (a) a hardening temperature (Th) from ?10° C. to about ?20° C. and a modulus measured at the Th lower than 5.0 MPa; or (b) a hardening temperature (Th) from ?20° C. to about ?30° C. and a modulus measured at the Th lower than 20.0 MPa; or (c) a hardening temperature (Th) lower than about ?30° C. and a modulus measured at the Th lower than 70.0 MPa.

Abstract: An optical fiber having: a) a glass portion; and b) at least one protective coating layer disposed to surround the glass portion, the protective coating layer having a modulus of elasticity value between ?40° C. and +60° C. between 5 MPa and 600 MPa, preferably not higher than 500 MPa, more preferably not higher than 450 MPa and much more preferably not higher than 300. Preferably the protective coating layer is a single protective coating layer which is disposed in contact with the glass portion.

Abstract: Optical fiber capable of controlling attenuation losses caused by microbending on the signal transmitted thereby. The optical fiber comprises: a) an internal glass portion; b) a first coating layer of a first polymeric material surrounding said glass portion; and c) a second coating layer of a second polymeric material surrounding said first coating layer, wherein said first polymeric material has a hardening temperature lower than ?10° C., an equilibrium tensile modulus lower than 1.5 MPa, wherein said first coating layer has a thickness of from 18 ?m to 28 ?m and wherein said second coating layer has a thickness of from 10 ?m to 20 ?m.

Abstract: Optical fiber having a glass portion; at least one protective coating of thermoplastic material having at least one thermoplastic elastomer; the thermoplastic material having the following characteristics: a modulus of elasticity value at +25° C. lower than 150 MPa, preferably at least 10 Mpa, more preferably higher than 20 Mpa, and a Vicat point higher than 85° C., preferably higher than 120° C., more preferably lower than 350° C. Preferably, the coating is a single protective coating directly positioned onto the glass portion.

Abstract: Optical fiber capable of controlling attenuation losses caused by microbending on the signal transmitted thereby. The optical fiber comprises: a) an internal glass portion; b) a first coating layer of a first polymeric material surrounding said glass portion; and c) a second coating layer of a second polymeric material surrounding said first coating layer, wherein said first polymeric material has a hardening temperature lower than ?10° C., an equilibrium tensile modulus lower than 1.5 MPa, wherein said first coating layer has a thickness of from 18 ?m to 28 ?m and wherein said second coating layer has a thickness of from 10 ?m to 20 ?m.

Abstract: An optical fiber having at least one epoxidized polyolefin based polymer coating. The coating is formed from a crosslinkable composition having (a) at least one epoxidized polydiene oligomer having a first and a second end, the oligomer having at least one hydrocarbon chain that is substantially free of ethylenic double bonds, at least one epoxide group at the first end and at least one reactive functional group at the second end; (b) at least one hydrogenated polydiene oligomer having at least one reactive functional group capable of reacting with the epoxide groups; and (c) at least one photo-initiator. Preferably, the coating is a primary coating coated with a secondary coating.

Abstract: A method for controlling attenuation losses caused by microbending on the signal transmitted by an optical fiber having an internal glass portion. A first coating layer of a first polymeric material surrounds the glass portion and a second coating layer of a second polymeric material surrounds the first coating layer. The first polymeric material has a hardening temperature lower than 10° and an equilibrium modulus lower than 1.5 MPa.

Abstract: Optical fiber having a glass portion; at least one protective coating of thermoplastic material having at least one thermoplastic elastomer; the thermoplastic material having the following characteristics: a modulus of elasticity value at +25° C. lower than 150 MPa, preferably at least 10 Mpa, more preferably higher than 20 Mpa, and a Vicat point higher than 85° C., preferably higher than 120° C., more preferably lower than 350° C. Preferably, the coating is a single protective coating directly positioned onto the glass portion.

Abstract: An optical fiber having an internal glass portion, a first coating layer surrounding the glass portion and a second coating layer surrounding the first coating layer. The first coating layer is formed from a cured polymeric material obtained by curing a radiation curable composition having a radiation curable oligomer having a backbone derived from polypropylene glycol and a dimer acid based polyester polyol. The cured polymeric material has: (a) a hardening temperature (Th) from ?10° C. to about ?20° C. and a modulus measured at the Th lower than 5.0 MPa; or (b) a hardening temperature (Th) from ?20° C. to about ?30° C. and a modulus measured at the Th lower than 20.0 MPa; or (c) a hardening temperature (Th) lower than about ?30° C. and a modulus measured at the Th lower than 70.0 MPa.

Abstract: An optical fiber having at least one epoxidized polyolefin based polymer coating. The coating is formed from a crosslinkable composition having (a) at least one epoxidized polydiene oligomer having a first and a second end, the oligomer having at least one hydrocarbon chain that is substantially free of ethylenic double bonds, at least one epoxide group at the first end and at least one reactive functional group at the second end; (b) at least one hydrogenated polydiene oligomer having at least one reactive functional group capable of reacting with the epoxide groups; and (c) at least one photo-initiator. Preferably, the coating is a primary coating coated with a secondary coating.

Abstract: An optical fiber having at least one epoxidized polyolefin based polymer coating. The coating is formed from a crosslinkable composition having (a) at least one epoxidized polydiene oligomer having a first and a second end, the oligomer having at least one hydrocarbon chain that is substantially free of ethylenic double bonds, at least one epoxide group at the first end and at least one reactive functional group at the second end; (b) at least one hydrogenated polydiene oligomer having at least one reactive functional group capable of reacting with the epoxide groups; and (c) at least one photo-initiator. Preferably, the coating is a primary coating coated with a secondary coating.

Abstract: The present invention relates to a radiation curable coating composition comprising a radiation curable oligomer comprising a backbone derived from polypropylene glycol and a dimer acid based polyester polyol, wherein said coating composition, when cured, is having: a) a hardening temperature (Th) of from ?10° C. to about ?20° C. and a modulus measured at said Th of lower than 5.0 MPa; or b) a hardening temperature (Th) of from ?20° C. to about ?30° C. and a modulus measured at said Th of lower than 20.0 MPa; or c) a hardening temperature (Th) of lower than about ?30° C. and a modulus measured at said Th of lower than 70.0 MPa.

Abstract: A method for controlling attenuation losses caused by microbending on the signal transmitted by an optical fiber having an internal glass portion. A first coating layer of a first polymeric material surrounds the glass portion and a second coating layer of a second polymeric material surrounds the first coating layer. The first polymeric material has a hardening temperature lower than 10° and an equilibrium modulus lower than 1.5 MPa.

Abstract: An optical fiber having at least one epoxidized polyolefin based polymer coating. The coating is formed from a crosslinkable composition having (a) at least one epoxidized polydiene oligomer having a first and a second end, the oligomer having at least one hydrocarbon chain that is substantially free of ethylenic double bonds, at least one epoxide group at the first end and at least one reactive functional group at the second end; (b) at least one hydrogenated polydiene oligomer having at least one reactive functional group capable of reacting with the epoxide groups; and (c) at least one photo-initiator. Preferably, the coating is a primary coating coated with a secondary coating.