What is the difference between separated lining film woven bags and laminated plastic woven bags?

Waterproof and Sealed Plastic Woven Bags: Separated Lining Film vs. Laminated Plastic

In the cement, fertilizer, and sugar industries, plastic woven bags are not only packaging materials but also an important barrier to protecting product quality. To meet the special requirements of these industries for waterproof and sealing functions, plastic woven bags must have excellent moisture resistance and sealing properties. Two main types of waterproof and sealed woven bags are widely used in China today: separated lining film woven bags and laminated plastic woven bags. This article provides a detailed analysis of the production process, advantages and disadvantages, and application scenarios of these two woven bag types.

1. Separated Lining Film Woven Bags

1.1. Structure and Characteristics

Separated lining film woven bags consist of an inner bag and an outer bag:

• Inner Bag: A plastic film bag made by a film blowing process, providing good waterproofness and sealing properties.
• Outer Bag: Made of plastic woven cloth, offering high strength and wear resistance.
• Size Design: The length and width of the inner bag are slightly larger than the outer bag to ensure complete coverage.

1.2. Production Process

• Film Blowing Process: The inner bag is made using a film blowing machine to ensure uniformity and sealing.
• Manual Bagging: The inner bag and the outer bag are manually put together, with the bag openings aligned for sewing.
• Equipment Investment: The production equipment is relatively simple, and the investment cost is low.

1.3. Advantages

• Good Waterproofness: The plastic film of the inner bag provides excellent moisture resistance and sealing.
• Low Cost: The simple production process and small equipment investment make it suitable for small and medium-sized enterprises.

1.4. Disadvantages

• Low Production Efficiency: The manual bagging and sewing process is time-consuming and labor-intensive, preventing continuous and efficient production.
• Easy to Break: The outer bag is easily damaged when force is unevenly applied, affecting the packaging’s durability.

2. Laminated Plastic Woven Bags

2.1. Structure and Features

Laminated plastic woven bags are made by coating the outer surface of the woven cylindrical cloth with a layer of plastic film (0.02~0.04mm thick) to form an integrated waterproof sealing structure.

2.2. Production Process

• Lamination Process: A laminator combines the plastic film extruded at high temperatures (around 300℃) with the woven cloth, bonding them firmly through a cooling roller.
• High-Temperature Effect: High-temperature lamination reduces the strength and elasticity of the woven cloth, increasing the bag’s brittleness.

2.3. Advantages

• Integrated Design: The inner and outer layers are tightly combined, avoiding the bagging problem of separated woven bags.
• High Production Efficiency: The lamination process enables continuous production, improving efficiency.

2.4. Disadvantages

• Brittleness Problem: High-temperature lamination reduces the woven cloth’s strength, making the bag body easily damaged when dropped or under pressure.
• High Equipment Investment: The laminating equipment and technology requirements are high, resulting in a large initial investment cost.

3. Comparison Between Separated Lining Film and Laminated Woven Bags

4. Application Scenarios of Waterproof and Sealed Woven Bags

1. Cement Industry:
   Cement packaging requires high moisture resistance and sealing, and both separated lining film woven bags and laminated woven bags can meet these needs.
2. Fertilizer Industry:
   Fertilizer packaging requires woven bags with excellent waterproof and chemical corrosion resistance, making laminated woven bags a better choice.
3. Sugar Industry:
   Sugar products easily absorb moisture and require highly sealed packaging. Separated lining film woven bags offer better waterproof performance.

5. How to Choose Suitable Waterproof and Sealed Woven Bags

1. Choose According to Purpose:
   • Cement and Fertilizer: Prefer laminated woven bags, considering waterproofness and production efficiency.
   • Sugar Products: Choose separated lining film woven bags to ensure high sealing.
2. Consider Production Efficiency:
   If large-scale production is required, laminated woven bags are a more efficient choice.
3. Evaluate Cost and Durability:
   Separated woven bags have low cost but poor durability, while laminated woven bags have high cost but high production efficiency.

6. Future Development Trends

1. Application of Environmentally Friendly Materials:
   With increasing environmental protection requirements, degradable plastic films and environmentally friendly laminating technology will become the trend.
2. Intelligent Production:
   Introducing intelligent equipment can improve the accuracy and efficiency of the laminating process and reduce the impact of high temperatures on woven fabrics.
3. Multifunctional Design:
   In the future, waterproof and sealed woven bags will not only have waterproof functions but may also integrate features such as UV protection and antibacterial properties.

Conclusion

Waterproof and sealed woven bags play an important role in industries such as cement, fertilizer, and sugar. Understanding the production process, advantages and disadvantages, and application scenarios of separated liner film woven bags and laminating plastic woven bags enables you to choose the most suitable packaging solution according to your specific needs. With the advancement of technology, waterproof and sealed woven bags will play an increasingly important role, providing efficient and reliable packaging support for various industries.