D1364 bt secondary coatings on optical fiber

Abstract

The invention relates to a Radiation Curable Secondary Coating composition for use on an Optical Fiber. The Radiation Curable Secondary Coating composition is a urethane-free Alpha Oligomer prepared by reaction of the following: (a) an acrylate compound selected from an alcohol-containing acrylate or alcohol-containing methacrylate compound, (b) an anhydride compound, (c) an epoxy-containing compound, (d) optionally an extender compound, and (e) optionally a catalyst. The invention also relates to a coated wire and to a coated optical fiber.

1 . A Radiation Curable Secondary Coating composition comprising a urethane-free Alpha Oligomer prepared by reaction of the following:
 (a) an acrylate compound selected from an alcohol-containing acrylate or alcohol-containing methacrylate compound,   (b) an anhydride compound,   (c) an epoxy-containing compound,   (d) optionally an extender compound, and   (e) optionally a catalyst.   
     
     
         2 . The Radiation Curable Secondary Coating composition of  claim 1  further comprising a Beta Oligomer, and, optionally, a Gamma Oligomer; wherein said Beta Oligomer is different from said Alpha Oligomer. 
     
     
         3 . The Radiation Curable Secondary Coating composition of  claim 2 , wherein said composition further comprises an antioxidant; a first photoinitiator; a second photoinitiator; and optionally a single slip additive or a blend of slip additives;
 wherein said Beta Oligomer is prepared by the reaction of
 β1) hydroxyethyl acrylate; 
 β2) one or more diisocyanates; 
 β3) a polypropylene glycol with a number average molecular weight of about 1000; and 
 β4) a catalyst; 
   wherein the Beta oligomer catalyst is selected from the group consisting of dibutyl tin dilaurate; metal carboxylates, including, but not limited to: organobismuth catalysts such as bismuth neodecanoate, CAS 34364-26-6; zinc neodecanoate, CAS 27253-29-8; zirconium neodecanoate, CAS 39049-04-2; and zinc 2-ethylhexanoate, CAS 136-53-8; sulfonic acids, including but not limited to dodecylbenzene sulfonic acid, CAS 27176-87-0; and methane sulfonic acid, CAS 75-75-2; amino or organo-base catalysts, including, but not limited to: 1,2-dimethylimidazole, CAS 1739-84-0; and diazabicyclo[2.2.2]octane (DABCO), CAS 280-57-9; and triphenyl phosphine; alkoxides of zirconium and titanium, including, but not limited to zirconium butoxide, (tetrabutyl zirconate) CAS 1071-76-7; and titanium butoxide, (tetrabutyl titanate) CAS 5593-70-4; and ionic liquid phosphonium, imidazolium, and pyridinium salts, such as, but not limited to, trihexyl(tetradecyl)phosphonium hexafluorophosphate, CAS No. 374683-44-0; 1-butyl-3-methylimidazolium acetate, CAS No. 284049-75-8; and N-butyl-4-methylpyridinium chloride, CAS No. 125652-55-3; and tetradecyl(trihexyl) phosphonium chloride; and   wherein said Gamma Oligomer is an epoxy diacrylate.   
     
     
         4 . A optical fiber coated with a Radiation Curable Primary Coating and the Radiation Curable Secondary Coating of  claim 1 . 
     
     
         5 . An optical fiber coated with a Radiation Curable Primary Coating and the Radiation Curable Secondary Coating of  claim 2 . 
     
     
         6 . An optical fiber coated with a Radiation Curable Primary Coating and the Radiation Curable Secondary Coating of  claim 3 . 
     
     
         7 . A process for coating an optical fiber, the process comprising:
 a) operating a glass drawing tower to produce a glass optical fiber; and   b) coating said glass optical fiber with a radiation curable Primary Coating composition;   c) optionally contacting said radiation curable Primary Coating composition with radiation to cure the coating;   d) coating said glass optical fiber with the radiation curable Secondary Coating composition of  claim 1 ;   e) contacting said radiation curable Secondary Coating composition with radiation to cure the coating;   
     
     
         8 . The process of  claim 7  wherein said glass drawing tower is operated at a line speed of between about 750 meters/minute and about 2100 meters/minute. 
     
     
         9 . A wire coated with a first and second layer, wherein the first layer is a cured radiation curable Coating that is in contact with the outer surface of the wire and the second layer is a cured radiation curable Secondary Coating of  claim 1  in contact with the outer surface of the Primary Coating,
 wherein the cured Secondary Coating on the wire has the following properties after initial cure and after one month aging at 85° C. and 85% relative humidity:   A) a % RAU of from about 80% to about 98%;   B) an in-situ modulus of between about 0.60 GPa and about 1.90 GPa; and   C) a Tube Tg, of from about 50° C. to about 80° C.   
     
     
         10 . An optical fiber coated with a first and second layer, wherein the first layer is a cured radiation curable Primary Coating that is in contact with the outer surface of the optical fiber and the second layer is a cured radiation curable Secondary Coating of  claim 1  in contact with the outer surface of the Primary Coating,
 wherein the cured Secondary Coating on the optical fiber has the following properties after initial cure and after one month aging at 85° C. and 85% relative humidity:   A) a % RAU of from about 80% to about 98%;   B) an in-situ modulus of between about 0.60 GPa and about 1.90 GPa; and   C) a Tube Tg, of from about 50° C. to about 80° C.   
     
     
         11 . A wire coated with a first and second layer, wherein the first layer is a cured radiation curable Primary Coating that is in contact with the outer surface of the wire and the second layer is a cured radiation curable Secondary Coating of  claim 2  in contact with the outer surface of the Primary Coating,
 wherein the cured Secondary Coating on the wire has the following properties after initial cure and after one month aging at 85° C. and 85% relative humidity:   A) a % RAU of from about 80% to about 98%;   B) an in-situ modulus of between about 0.60 GPa and about 1.90 GPa; and   C) a Tube Tg, of from about 50° C. to about 80° C.   
     
     
         12 . An optical fiber coated with a first and second layer, wherein the first layer is a cured radiation curable Primary Coating that is in contact with the outer surface of the optical fiber and the second layer is a cured radiation curable Secondary Coating of  claim 2  in contact with the outer surface of the Primary Coating,
 wherein the cured Secondary Coating on the optical fiber has the following properties after initial cure and after one month aging at 85° C. and 85% relative humidity:   A) a % RAU of from about 80% to about 98%;   B) an in-situ modulus of between about 0.60 GPa and about 1.90 GPa; and   C) a Tube Tg, of from about 50° C. to about 80° C.   
     
     
         13 . A wire coated with a first and second layer, wherein the first layer is a cured radiation curable Primary Coating that is in contact with the outer surface of the wire and the second layer is a cured radiation curable Secondary Coating of  claim 3  in contact with the outer surface of the Primary Coating,
 wherein the cured Secondary Coating on the wire has the following properties after initial cure and after one month aging at 85° C. and 85% relative humidity:   A) a % RAU of from about 80% to about 98%;   B) an in-situ modulus of between about 0.60 GPa and about 1.90 GPa; and   C) a Tube Tg, of from about 50° C. to about 80° C.   
     
     
         14 . An optical fiber coated with a first and second layer, wherein the first layer is a cured radiation curable Primary Coating that is in contact with the outer surface of the optical fiber and the second layer is a cured radiation curable Secondary Coating of  claim 3  in contact with the outer surface of the Primary Coating,
 wherein the cured Secondary Coating on the optical fiber has the following properties after initial cure and after one month aging at 85° C. and 85% relative humidity.   A) a % RAU of from about 80% to about 98%;   B) an in-situ modulus of between about 0.60 GPa and about 1.90 GPa; and   C) a Tube Tg, of from about 50° C. to about 80° C.