The key to choosing FIBC (FIBC/FIBC) liner film lies in determining the material, thickness, and function based on the material characteristics and transportation environment. Here are some frequently asked questions and answers regarding how to choose FIBC liner film for bag packaging.We hope our article can help you.
Q1: What is the core function of an FIBC liner? Can't the outer bag provide moisture protection?
The outer woven polypropylene (PP) FIBC bag is primarily designed to provide structural strength and load-bearing capacity. It is breathable and offers almost no moisture or oxygen barrier. Moisture, oxygen, and dust can freely pass through the woven fabric.
The inner liner is the actual protective barrier. Its core functions are:
Moisture/Oxygen Barrier: Protects sensitive products (e.g., milk powder, chemicals, coffee) from degradation caused by moisture and oxygen.
Containment & Contamination Prevention: Prevents fine powders from sifting through the outer bag's weave, and stops external contaminants from entering.
Advanced Features: Provides additional properties like anti-static protection, high-temperature resistance, and chemical compatibility.
Q2: How do I choose the right liner material based on my product?
The table below summarizes the common material choices:
|
Characteristic |
Recommended Liner Material |
Rationale |
|
Highly sensitive to moisture/oxygen (e.g., milk powder, nuts, coffee, pharmaceuticals) |
EVOH Multi-layer Coextruded Film |
EVOH provides top-tier oxygen barrier; aluminum laminate offers near-perfect total barrier (oxygen, moisture, light) for maximum shelf life. |
|
High strength & puncture resistance needed (e.g., sharp-edged granules, heavy products) |
Polyamide (PA/Nylon) Composite Film |
The PA layer delivers outstanding puncture resistance, tear strength, and impact resistance to prevent damage during transport. |
|
Hot-fill applications (e.g., hot asphalt, hot cement) |
Polypropylene (PP) or PA Composite Film |
Can withstand high filling temperatures up to 140–170°C. |
|
General moisture/dust protection (for non-oxygen-sensitive chemicals, powders) |
Polyethylene (PE) |
Economical, provides basic moisture and contamination protection, and has excellent heat-sealability. |
Q3: What are the key performance metrics for evaluating a liner film's barrier?
A:Oxygen Transmission Rate (OTR) and Water Vapor Transmission Rate (WVTR)
Send your product, packaging machine and shelf-life requirement. Fuya can recommend a suitable multilayer film structure.
