Spout-Equipped Packaging Bag Flange Adhesion for Self-Standing Stability

Instead of narrowing the upper portion of the bag body to attach the spout (conventional approach), the invention inverts the approach by spreading the upper portion in the width direction. This inverted design allows the spout to be attached to a flattened upper portion while maintaining self-standing properties even when contents decrease, as the spread shape provides sufficient structural support to counteract the spout's weight.

Instead of attaching the spout to the bottom portion (which provides self-standing properties but poor cap security), the invention inverts the conventional upper-portion attachment by spreading the upper portion in the width direction to create a flattened shape. This inverted approach maintains the spout's upward orientation for better cap security while achieving self-standing properties through the spread shape of the upper portion.

The invention extracts the harmful annular seal portion that protrudes upward and contacts the user's face. Instead of forming a continuous annular seal throughout the entire circumference, the invention selectively forms seal portions only in specific regions (such as at the corners or edges of the gusset portions), removing the protruding seal from the central area where it would contact the face during drinking, thereby eliminating user discomfort while maintaining necessary sealing functionality.

The invention extracts the harmful Y-shaped seal portion with its hard intersection part that causes discomfort to the hand. Instead of forming seals at all three intersections (top surface to side walls and side walls to each other), the invention selectively forms seals only where necessary for structural integrity, omitting the seal that would create the Y-shaped intersection, thereby eliminating the hard protrusion that causes hand discomfort while maintaining adequate structural stability.