Packaging container for receiving bulk material, and method of and apparatus for making a flat packaging container as well as ventilating and sealing the filled packaging container

A method of packaging powdery material, comprising the steps of:

• shaping a moisture-proof, thermoplastic layer such that opposite ends overlap each other to form an inner layer and an outer layer in an overlap zone;
• sealing the inner layer and the outer layer along a longitudinal seam at a spaced location from the end of the outer layer to form a packaging container;
• that has one closed end and a material receiving end
• forming a ventilation zone between said longitudinal seam and the end of the outer layer in the overlap zone;
• filling the packaging with powdery material through said material receiving end while said air escapes through said ventilation zone;
• and
• closing said material receiving end and sealing the ventilation zone of the thermoplastic layer along a further longitudinal seam through heat sealing or welding immediately before transferring the packaging container to a subsequent peripheral unit.