| 摘要 |
PURPOSE:To provide a titled medium having excellent mechanical and optical properties and resistance to heat, moisture and weather by sticking two sheets of substrates to each other by a reactive hot melt adhesive agent prepd. by incorporating an urethane prepolymer having isocyanate groups at both terminals into a tackiness imparting resin. CONSTITUTION:The recording media 4 formed with recording layers 2 and protective films covering the same on two sheets of the transparent substrate 1 are joined to one body on the protective film 3 side by the adhesive agent 5. The adhesive agent t is constituted by the reactive hot melt adhesive agent prepd. by incorporating the urethane prepolymer having the isocyanate groups at both terminals into the tackiness imparting resin at a prescribed ratio. Said adhesive agent contains 30-69.8wt% urethane prepolymer, 30-55wt% tackiness imparting resin of at least one kind among a cumarone resin or cumarone-indene resin (a), terpene-phenolic resin (b), specific rosin deriv. (c) and styrene resin (d), and 0.2-25wt% arom. oil. |
