Common Problems Of Back Seal Edge Bag

A back-seal gusset bag (or "back-seal gusset bag") is a bag type made by rolling a roll of film into a cylindrical shape and then heat-sealing the back and the top and bottom of the bag. Its biggest feature is that the two sides of the bag are folded inward at two places to form a "clamped edge" structure, allowing the bag to be unfolded into a nearly cubic shape when in use. This design not only increases the capacity of the bag, but also allows the contents to stand more firmly for easy display.

The main difference is the "clip edge". Generally, back-sealed bags are made by simply heat-sealing the film on the back to form a flat bag with a relatively fixed capacity. The back-seal hem bag creates extra space through the inward folding design on both sides, allowing it to expand after being filled with contents, forming a three-dimensional effect. This allows the back-seal gusseted bag to hold more items and provide better stability and presentation on the shelf.

Back-seal bags are widely used in packaging of various products due to their superior capacity and stability, including:

• Snack foods: biscuits, potato chips, nuts, candies, etc.
• Coffee beans/ground: A good seal helps keep the coffee fresh.
• Pet food: cat food, dog food, etc.
• Powdered products: flour, milk powder, condiments, etc.
• Small bulk items: toys, stationery, etc.

Back-seal gusset bags have several advantages that make them a popular packaging choice:

• Increased Capacity: The clip-on design effectively expands the bag's internal space, allowing it to hold more items.
• Good stability: The three-dimensional shape after unfolding allows the bag to stand firmly, making it easy to display and store.
• Good display effect: The three-dimensional appearance makes the product more visually attractive on the shelf and enhances the brand image.
• Strong sealing: The design of the back seal and upper and lower seals ensures that the contents are not easily affected by moisture or deterioration.
• High production efficiency: Compared with some complex bag types, the production process of back-seal and edge-clamped bags is relatively mature and has higher production efficiency.

The material of the back-seal bag depends on the characteristics of the packaged product and the storage requirements. Common material combinations include:

• BOPP/CPP: Economical and affordable, commonly used in general snack foods, with good moisture resistance.
• PET/AL/PE: It has excellent barrier properties (moisture-proof, oxygen-proof, and light-proof), and is very suitable for products that require a high degree of freshness preservation, such as coffee and tea.
• PET/VMPET/PE: VMPET (aluminum-coated film) provides good barrier properties and metallic luster, and its cost is lower than that of aluminum foil. It is suitable for products that require freshness but have limited budgets.
• Kraft Paper/AL/PE or Kraft Paper/VMPET/PE: Suitable for products that pursue environmental protection or natural style while maintaining good barrier properties.