With the increasing market penetration of biodegradable bags, choosing the right packaging format has become a practical issue for consumers. Which is more environmentally friendly and meets usage needs: roll packaging (such as pull-out roll packaging) or flat packaging (such as stackable flat packaging)?
I. Comparison of Packaging Material Consumption and Environmental Impact
Roll bags require paper cores and connecting materials, consuming an average of 15%-20% more packaging materials. Flat packaging primarily uses cardboard boxes; using recycled pulp can significantly reduce the environmental impact. From a life-cycle perspective, simplifying packaging design and using renewable materials are key paths to reducing environmental impact.
1. Material Structure Characteristics of Roll Bags
(1) Bags are usually connected by tear-off joints with an overlap of about 2-3mm.
(2) Requires paper or plastic core tube support; the core tube diameter is usually 3-5cm.
(3) Mostly wrapped in plastic film; some high-end products use biodegradable film.
2. Flat Packaging Methods
(1) Bags are stacked flat, with no connecting material consumption.
(2) Anti-stick coating or spacer paper may be used between bags.
(3) Packed in cardboard boxes or soft bags; cardboard boxes are usually recyclable. 3. Material Consumption Quantitative Comparison
Taking 100 standard-sized pet bags as an example:
(1) Total weight of roll packaging: bag weight + core tube (approx. 15g) + connecting material (approx. 8g)
(2) Total weight of flat packaging: bag weight + wrapping paper (approx. 5g)
(3) Difference Analysis: Roll packaging consumes an average of 15%-20% more packaging material.
II. Transportation and Storage Efficiency Analysis
In terms of transportation and storage efficiency, flat packaging, with its regular rectangular shape, achieves a space utilization rate of over 85%, making it easier to standardize stacking and storage. In contrast, roll packaging, due to its cylindrical shape, requires anti-roll measures in storage, and the single-box load-bearing limit may reduce the loading capacity.
Comprehensive calculations show that flat packaging can reduce carbon emissions per unit of product transportation by approximately 18%, and also has lower storage management costs. 
1. Space Utilization Efficiency
(1) Cylindrical shape provides good filling properties and is less prone to deformation during transportation.
(2) Rectangular packaging facilitates standardized stacking, achieving a space utilization rate of over 85%.
2. Weight Distribution Comparison
(1) Roll packaging: Weight is concentrated, and the load-bearing capacity of a single box may affect the loading volume.
(2) Flat packaging: Weight is dispersed, making it more suitable for the load-bearing requirements of large-scale warehousing.
3. Transportation Carbon Emission Calculation
Based on transporting 10,000 products in a standard 40-foot container:
(1) Roll packaging: Can load approximately 120 boxes, each with a volume of 0.025 m³
(2) Flat packaging: Can load approximately 150 boxes, each with a volume of 0.018 m³
(3) Carbon emission difference: Flat packaging can reduce carbon emissions per unit of product transportation by approximately 18%
4. Warehousing management costs
(1) Roll packaging: Requires anti-roll devices, higher warehousing requirements
(2) Flat packaging: Can be stored on standard shelves, with good compatibility with warehousing systems
III. Ease of use and user experience
Roll packaging design facilitates quick one-handed extraction, especially suitable for mobile scenarios such as dog walking; flat packaging facilitates accurate counting and separate carrying, and is neater when used in fixed locations. Both are environmentally friendly and practical, but the choice should be based on matching specific usage scenarios and personal habits.
1. Advantages of Roll Packaging
(1) One-handed operation: Hold the roll with one hand and pull it out with the other, suitable for mobile scenarios such as walking the dog
(2) Continuous use: Quick and efficient continuous bag retrieval
(3) Vehicle use: The roll can be placed in the car door storage compartment, and it is not easy to scatter
2. Applicable scenarios for Flat Packaging
(1) Fixed locations at home: Such as the entrance cabinet and storage room, stacked neatly and beautifully
(2) Accurate counting: The remaining quantity is clear at a glance
(3) Small quantity carrying: A number of bags can be taken out as needed and put into the bag, reducing the burden of carrying them
3. Special usage needs
(1) Outdoor activities: Roll packaging is more suitable for windy and rainy weather, and the bags are more protected
(2) Multi-scene switching: Flat packaging can be divided into small bags and flexibly allocated to different usage points
(3) Elderly users: Flat packaging is easier to grasp one bag at a time, and the coordination requirements are lower
IV. Product protection and preservation performance
The roll packaging structure can effectively block external pollution and is suitable for humid environments; the flat packaging is affected by temperature and humidity evenly, which is more conducive to long-term stable preservation.
Both have their own focuses on dust and moisture protection, but both require attention to avoidance of light and moisture to ensure the stable performance of biodegradable materials within their shelf life.
1. Pollution Protection
(1) Roll Packaging: Only the outermost bag is exposed, and the inner bags are kept clean.
(2) Flat Packaging: The stacking design may cause dust to accumulate on the edge bags.
2. Temperature and Humidity Influence
(1) Roll Packaging: Temperature differences between the inside and outside may cause condensation on the inner layer.
(2) Flat Packaging: More uniformly affected by ambient temperature and humidity.
(3) Degradation Sensitive Period: In humid environments, the inside of the roll may begin to degrade before the outside of the PLA material.
3. Shelf Life Differences
Under standard storage conditions (25℃, RH50%):
(1) Roll Packaging Packaging: The degradation rate of the central part is 15-20% slower than that of the outside.
(2) Flat packaging: The degradation rate is uniform throughout.
(3) Actual shelf life: Roll packaging may be 3-6 months longer than flat packaging.
V. Production cost and price factors Production process comparison:
1. Roll packaging production process
(1) Bag making → Printing → Point break connection → Winding → Core tube installation → Outer packaging
(2) Requires special winding equipment, high equipment investment
(3) Production speed: Medium, about 60-80 meters/minute
2. Flat packaging production process:
(1) Bag making →Printing→Stacking and counting→Boxing and packaging
(2) The equipment is highly versatile and can be shared with other flexible packaging lines
(3) Production speed: High, up to 100-120 meters/minute
Cost composition analysis:
1. Based on a production volume of 10,000 units
(1) Roll packaging: Equipment depreciation accounts for 12%, labor accounts for 18%, and materials account for 65%
(2) Flat packaging: Equipment depreciation accounts for 8%, labor accounts for 15%, and materials account for 72%
(3) Total cost difference: Roll packaging is usually 10%-15% higher than flat packaging
2. Retail price Factors influencing price:
(1) Consumer perception: Roll packaging is often seen as “convenience-oriented,” with high acceptance of premium pricing.
(2) Packaging cost pass-through: Roll packaging costs account for 8%-12% of the selling price, while flat packaging accounts for 5%-8%.
(3) Market positioning: Roll packaging is mostly sold in high-premium channels such as convenience stores, while flat packaging is mostly sold in low-price channels such as supermarkets.
VI. Conclusion: The choice depends on the core needs of the usage scenario.
Roll packaging is suitable for outdoor mobile scenarios, providing quick and continuous access convenience; flat packaging is more suitable for fixed-point home use, facilitating precise control and packaging management. Both forms have their own environmental characteristics and usage advantages, and there is no absolute superiority or inferiority.
Consumers should make rational choices based on their main usage scenarios, environmental preferences, and storage conditions to ensure a balance between environmental benefits and user experience.
