Composite foil for book-binding - coated with pref. syrtene-butadiene-styrene copolymer-contg. melt adhesive

Abstract

Abstract Composite foil for book-binding consists of a carrier layer of synthetic polymer, pref. corona-treated polyvinyl acetate-primed biaxially oriented polyethylene terephthalate foil, coated on >=1 side with a mainly continuous melt-adhesive layer of synthetic, organic, thermoplastic-ealstomeric polymer (I) which on extension at room temp. at strain-rate 12.7 cm/min. causes a tensile stress 18 (11-14) kg/cm2 in 50-4000% extension-range and has stress-relaxation value 40% after 1 min. and viscosity >12000 (15000) cP at 177 degrees C. Pref. (I) is a segmented polymer having structure A-B-A (where each A is a non-elastomeric polymer segment having av. mol. wt. 2000-100000 and vitreous transition temp. >25 degrees C, pref. a polymerised alkenyl aromatic cpd. partic. styrene and each B is an elastomeric polymer segment having av.mol.wt. 25000-1000000 and vitreous transition temp. 10 degrees C pref. a polymerised conjugated diene, partic. butadiene). Melt-adhesive pref. contains 30-50% styrene-butadiene-styrene copolymer, a colophonic acid adhesive agent and a petroleum wax.

Inventors

• 👤 Thomas W Featherstone
• 👤 Edward L Schulke

Bibliographic Details