Radiation Curable Coating Composition

Abstract

The invention relates to a radiation curable composition including a polyester urethane (meth)acrylate oligomer prepared from ortho-carboxylic polyester polyols, where the composition, after cure, has a secant modulus greater than about 600 MPa and an elongation at break of at least about 10%. The invention also relates to coated optical fibers and optical fiber ribbon including at least one coating derived from this composition, and to a process of making these coated optical fibers.

1 . A radiation curable composition comprising a polyester urethane (meth)acrylate oligomer prepared from ortho-carboxylic polyester polyols, wherein said composition, after cure, has a secant modulus greater than 600 MPa and an elongation at break of at least 10%. 
   
   
       2 . The composition according to  claim 1 , wherein said composition has a glass transition temperature greater than 45° C. 
   
   
       3 . The composition according to  claim 1 , wherein said composition has a viscosity of 1400 mPa·s to 4000 mPa·s at 25° C. 
   
   
       4 . The composition according to  claim 1 , wherein said composition, when cured, maintains mechanical integrity when aged at 85° C. and 85% Relative Humidity for 12 weeks. 
   
   
       5 . The composition according to  claim 1 , wherein the composition when cured and aged for 12 weeks under 85° C. and 85% Relative Humidity shows a change in equilibrium modulus of 28% or less. 
   
   
       6 . The composition according to  claim 1 , wherein said composition further comprises one or more monomers and optionally, one or more photoinitiators. 
   
   
       7 . The composition according to  claim 1 , wherein said polyester urethane (meth)acrylate oligomer contains an aromatic urethane moiety. 
   
   
       8 . The composition according to  claim 7 , wherein said oligomer has a molecular weight of 1000 to 1400. 
   
   
       9 . The composition according to  claim 1 , wherein said polyester urethane (meth)acrylate oligomer contains an aliphatic urethane moiety. 
   
   
       10 . The composition according to  claim 9 , wherein said oligomer has a molecular weight of 1100 to 1300. 
   
   
       11 . The composition according to  claim 1 , wherein said composition is a secondary coating, colored secondary coating, ink, matrix or upjacketing composition. 
   
   
       12 . The composition according to  claim 1 , wherein said ortho-carboxylic polyester polyols have a viscosity higher than 4,000 mPa·s at 25° C. 
   
   
       13 . A radiation-curable composition comprising:
 i) 40 wt %-80 wt % of a polyester urethane (meth)acrylate oligomer, relative to the total weight of the composition, prepared from ortho-carboxylic polyester polyols;   ii) 10wt %-60 wt %, relative to the total weight of the composition, of one or more monomers;   iii) 0 wt %-5 wt %, relative to the total weight of the composition, of one or more photoinitiators;   wherein said composition, after cure, has a secant modulus greater than 600 MPa and an elongation at break of at least 10%.   
   
   
       14 . The composition according to  claim 13 , wherein said composition has a glass transition temperature greater than 45° C. 
   
   
       15 . The composition according to  claim 13 , wherein said one or more monomers are selected from the group consisting of PEA, HDDA, IBOA, IBXA, SR-531, EONPA, BPAEDA, TPGDA, and TMPTA. 
   
   
       16 . The composition according to  claim 13 , wherein said composition, after cure, maintains mechanical integrity when aged at 85° C. and 85% Relative Humidity for 12 weeks. 
   
   
       17 . A radiation curable composition comprising:
 i) 40 wt %-80 wt % of a polyester urethane (meth)acrylate oligomer, relative to the total weight of the composition, prepared from ortho-carboxylic polyester polyols;   ii) 10 wt %-60 wt %, relative to the total weight of the composition, of one or more of monomers;   iii) 0 wt %-10_wt %, relative to the total weight of the composition, of one or more photoinitiators; wherein said composition, after cure, has: a) a secant modulus of 600 MPa to 1800 MPa;   b) an elongation at break of from 10% to 30%; and wherein said composition has:   c) a glass transition temperature of from 45° C. to 100° C.; and   d) a viscosity of from 1300 mPa·s to 6000 mpa·s at 25° C.   
   
   
       18 . The composition according to  claim 17 , wherein said composition further comprises one or more pigments. 
   
   
       19 . The composition according to  claim 17 , wherein said composition further comprises one or more dyes. 
   
   
       20 . A coated optical fiber comprising a coating formed from the radiation-curable composition according to  claim 1 .. 
   
   
       21 . An optical fiber ribbon comprising a plurality of coated optical fibers according to  claim 20 . 
   
   
       22 . The coated optical fiber of  claim 20  wherein said coating is a secondary coating, an ink coating, an upjacketing coating, or a matrix material coating. 
   
   
       23 . A process for forming a coated optical fiber comprising applying the composition according to  claim 1  as a secondary coating, ink coating, upjacketing coating or matrix material coating.