Plastic bag has two outer transverse seams in its base and parallel central seam connected by slanting outer seams, forming two flaps which spread as bag is filled to give flat base

摘要

The plastic bag has two outer transverse seams (8) in its base and a central seam (9) which is parallel to these. They are connected by slanting outer seams (12), forming two flaps which spread as the bag is filled to give a flat base.