Abstract: A vacuum cleaner filter bag formed from a blank including a sheet of air permeable filter paper, and which is folded to define a tubular container having closed ends with an access opening formed in the container for permitting the passage of air into the interior of the bag so that the air can be filtered. The bag is formed by folding the blank and applying adhesive material onto specific areas during the folding operation in order to form the bag. On the blank itself there is also pre-applied, by preprinting or extruding, a heat, self-stick or pressure sensitive type of adhesive material on specified areas, these areas being susceptible to tears. After the bag is formed, it is passed through a heat or pressure applying station which activates the preprinted or extruded adhesive material thereby providing reinforcement to the bag at the areas which tend to tear.

Abstract: A vacuum cleaner filter bag formed from a blank including a sheet of air permeable filter paper, and which is folded to define a tubular container having closed ends with an access opening formed in the container for permitting the passage of air into the interior of the bag so that the air can be filtered. The bag is formed by folding the blank and applying adhesive material onto specific areas during the folding operation in order to form the bag. On the blank itself there is also pre-applied, by preprinting or extruding, a heat, selfstick or pressure sensitive type of adhesive material on specified areas, these areas being susceptible to tears. After the bag is formed, it is passed through a heat or pressure applying station which activates the preprinted or extruded adhesive material thereby providing reinforcement to the bag at the areas which tend to tear.