FIELD: chemistry.
SUBSTANCE: packaging is suitable for sealing aluminium or polyethylene terephthalate films, as well as aluminium coated or polyethylene terephthalate coated films relative polypropylene, polystyrene or polyvinyl chloride substrates. The heat sealing system for coating consists of a film-forming dispersion of at least three different types of polymers A, B, AB and C, a system of organic solvents L containing the following mixture: L1) esters of aliphatic carboxylic acid with aliphatic alcohols and L2) aliphatic hydrocarbons. The weight ratio of L1 to L2 lies between 1 and 200 and the boiling point of the system of solvents under normal conditions is at most 105°C. Type A polymer is ethylene-propylene-diene rubber, type B polymer is a copolymer of (meth)acrylates, containing standard (meth)acrylates and a total of up to 15 wt % methacrylic acid and/or acrylic acid per type B polymer, type AB polymer is a graft polymer of type A and type B polymers and type C polymer is saturated polyester with hydroxyl number equal to 3-25 mg KOH/g.
EFFECT: heat sealing system is characterised by high heat resistance, good protective properties and short sealing time.
4 cl
