Biodegradable, recyclable flexible packaging container - comprises paper sack or bag with coating or sheet of thermoplastic starch

摘要

Container (I) comprises sack or bag of paper with coating or sheet of thermoplastic starch (II). (II) forms laminate with paper covering, pref. with film of (II) bonded to paper covering, or with heat-coated sheet of (II) on paper. (I) is formed by applying molten extruded sheet of (II) on paper layer. Paper layer is of sulphate or sulphite paper, pref. with surface wt. 20-250 g/sq.m. Surface wt. of (II) is 10-150 g/sq.m. Laminate has thin protective coat of polymer resin over (II). (I) comprises 2 or more layers, at least one being self-supporting sheet of (II), and pref. this sheet of (II) is between 2 adjacent further packaging layers, or else sheet of (II) forms sack or bag-shaped inner cladding of (I). Sheet of (II) is extruded. Film of (II) is 0.01-0.25mm thick. (I) has filling valve having part consisting of sheet of (II) for sealing (I), pref. with sheet of (II) being formed from tubular section of extruded sheet. ADVANTAGE - (II) forms barrier against moisture, smells, etc. and is biologically degradable and recyclable with the paper