Patent ID: 6534557
Filing Date: 2003-03-18
Classification: C03C,Y10T

Abstract:
A system for coating an optical glass fiber comprising:(i) a radiation-curable inner primary coating composition comprising at least one slip enhancing component, wherein said slip enhancing component is a high molecular weight polymeric oligomer comprising one or more polymeric blocks each having a molecular weight of at least about 2,000; said one or more polymeric blocks being independently selected from the group consisting of polyethers prepared from tetrahydrofuran, methyl-substituted tetrahydrofuran, and/or epoxybutane; polyolefins; polycarbonates; polyesters; polyamides; and copolymers thereof; and if said oligomer comprises more than one polymeric block, said more than one polymeric blocks being linked by urethane, urea, or thiourethane groups; (ii) a radiation-curable outer primary coating composition comprising an oligomer having at least one functional group capable of polymerizing under the influence of radiation, and wherein said inner primary coating composition, after radiation cure, has the following combination of properties: (a) a glass transition temperature of below 0Â° C.; and (b) adhesion to glass of at least 5 g/in when conditioned at 95% relative humidity; wherein said outer primary coating composition, after radiation cure, has a secant modulus of greater than 1000 MPa at 23Â° C.