Easily made flexible optical waveguide with good light transmission

摘要

Optical waveguide tube comprises a tubular mantle and a solid core with a higher refractive index than the mantle. The core consists of a resin (I) with a Tg of up to 50 deg C and an elastic modulus of up to 10<9> dyne/cm<2>. Also claimed is a method of making the waveguide. Pref. (I) is a copolymer of (a) (meth)acrylic acid or a lower alcohol (meth)acrylate with (b-1) an alkoxy- or aryloxy-(poly)alkylene glycol (meth)acrylate of formula H2C=C(R<1>)-CO-(OC-nH2n)m-OR<2> (II) or (b-2) a higher alkyl (meth)acrylate of formula H2C=C(R<1>)-COOR<3> (III) (where R<1> = H or Me; R<2> = alkyl or aryl; n, m = 1-10; R<3> = 8-20C alkyl). Esp. (I) is a copolymer of methyl (meth)acrylate with 2-methoxyethyl (meth)-acrylate or phenoxypolyethylene glycol (meth)acrylate; or a copolymer of methyl (meth)acrylate with a mixt. of 12 and 13C alkyl (meth)acrylates, opt. mixed with a phosphate, aromatic carboxylate, aliphatic carboxylic acid or carboxylate, glycol and/or glycol (meth)acrylate.