D1365 P RADIATION-CURABLE PRIMARY COATING FOR OPTICAL FIBRE Russian patent published in 2012 - IPC C03C25/10 

FIELD: chemistry.

SUBSTANCE: invention relates to radiation-curable coatings for use as primary coating for optical fibre. The radiation-curable primary coating composition contains: A) an oligomer; B) a first diluent monomer; C) a second diluent monomer; D) a photoinitiator; E) an antioxidant; and F) an adhesion promoter; wherein said oligomer is a product of reaction of: i) hydroxy ethyl acrylate; ii) aromatic isocyanate; iii) aliphatic isocyanate; iv) polyol; v) catalyst; vi) inhibitor. The oligomer has number-average molecular weight from at least 4000 g/mol to less than or equal to 15000 g/mol. The catalyst is selected from a group comprising dibutyl tin dilaurate, metal carboxylates, sulphonic acids, catalysts based on amines or organic bases, zirconium and titanium alkoxides, and ionic liquid salts of phosphonium, imidazolium and pyridinium. The solidified film of said radiation-curable primary coating composition has tan delta peak T_c from -25°C to -45°C and modulus of elasticity from 0.50 MPa to 1.2 MPa.

EFFECT: improved technological and operational characteristics of the coating.

7 cl, 4 tbl