It is a
Flexible Packaging container made of multi-layer composite film, featuring a bottom supporting structure for self-standing and a resealable spout. Its internationally recognized name is
Doypack pouch, which achieves three core functions: "standing storage, precise dispensing, and resealing".
- Self-supporting property: It has a specially folded or shaped bottom structure. When filled with contents, it can stand stably, saving storage and display space.
- Sealing property: The spout and pouch body are combined through precision welding, and with a screw-on or push-to-close design, the leakage rate can be controlled below 0.1%.
- Barrier property: The multi-layer composite material provides oxygen resistance, moisture resistance, light resistance, and other functions, extending the shelf life of the contents.
- Compatibility: It is suitable for contents of various forms, including liquids, semi-fluids, and granules, and can accommodate capacities ranging from 10ml to 5L.
Scientific proportioning of composite materials: functional division of layer structure
| Material Hierarchy | Core Functionality | Common material | Adaptation
scenarios |
| Outer layer (printing layer) | Load bearing and scratch resistant, printing carrier, protection | PET (polyethylene terephthalate) BOPP | Need to withstand friction test (50 times without obvious scratches), support 12 color environmentally friendly printing |
| Barrier layer (functional layer) | Oxygen barrier, moisture barrier, light avoidance, corrosion resistance | AL (aluminum foil) EVOH、VMPET、 Nano ceramic layer | High barrier oxygen permeability ≤ 5cm3/(m2 · 24h · 0.1MPa), moisture permeabilitys3g/(m?- 24h) |
| Inner layer (contact layer) | Food contact safety, heat sealing and sealing | PE (polyethylene), RCPP (high temperature resistant polypropylene) | Food grade products must comply with GB4806 standards, and high-temperature resistant products must withstand sterilization at temperatures above 121 ℃ |
- Three-side sealed type (universal, low cost)
- Eight-side sealed type (high load-bearing capacity, can hold over 5kg)
- Zipper-equipped type (more convenient for repeated opening and closing)
- The precision error of the self-supporting bottom heat-sealing knife is ≤ 0.5mm.
- Eight-step edge-sealing process improves structural stability.
- Ultrasonic spot-sealing technology enhances the sealing performance of the four-layer joint.
- Clarify core scenarios: For liquids/semi-fluids, prioritize pouches with an RCPP inner layer (high temperature-resistant); for solid dry goods, prioritize those with a high-barrier layer (AL/EVOH); for repeated use, choose screw-on spouts with zippers.
- Verify qualification standards: For food-contact pouches, request the GB 4806 test report; for medical-use pouches, require medical composite film certification; for eco-friendly pouches, check for biodegradable/recyclable labels.
- Test key performance: Conduct a sealing test (no leakage when inverted for 12 hours), a load-bearing test (no collapse when standing upright for 24 hours after filling), and a spout smoothness test (no jamming after 10 opening-closing cycles).
- Compare cost compatibility: Ordinary pouches cost 0.1-0.3 yuan per piece (suitable for catering takeaways); high-temperature-resistant pouches cost 0.5-1 yuan per piece (suitable for TCM pharmacies); high-barrier pouches cost 0.8-1.5 yuan per piece (suitable for food enterprises).
- Prohibited scenarios: Ordinary PE material cannot be used for high-temperature cooking above 135℃; non-corrosion-resistant pouches should avoid contact with strong acids and alkalis (e.g., toilet cleaners); disposable pouches cannot be reused for holding food.
- Storage key points: Avoid direct sunlight (to prevent material aging); control storage temperature between -20℃ and 40℃; keep away from sharp objects to prevent damage to the barrier layer.
- Safety tips: When cutting open the pouch, avoid the spout welding area; confirm the material’s temperature resistance level before heating; adult supervision is required when children use the pouch to prevent accidental swallowing of the spout parts.
The penetration rate of biodegradable materials continues to rise, and it is expected to reach over 22% by 2025. Technologies for bio-based PE and PLA/PBAT composite films are mature. Enterprises such as BASF have launched bio-based products that reduce carbon emissions by 40%. Meanwhile, the single-material design of full PE promotes the improvement of the recycling system, and some brands have launched closed-loop packaging recycling programs.
Smart labels are gradually becoming popular; embedded temperature and humidity sensor chips can monitor the freshness of contents in real time. Self-healing film technology addresses minor damages, improving transportation safety. Phase-change energy storage materials are applied in scenarios such as coffee concentrates, enabling room-temperature preservation for more than 6 months.
