FIBC Liner Types: LDPE, EVOH and Aluminium Barrier Guide

What is an FIBC Liner?

An FIBC liner is a plastic film lining placed inside the big bag or fixed to its body.

Main Functions

• Moisture barrier — Protects hygroscopic (moisture-attracting) products from absorbing moisture
• Oxygen barrier — Prevents oxidation and spoilage
• Contamination prevention — Separates the product from its surroundings
• Product retention — Prevents dust from escaping and allows clean discharge

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Liner Materials

1. LDPE (Low-Density Polyethylene)

The most widely used liner material.

Property	Value
Flexibility	High
Transparency	High
Moisture Barrier	Medium
Oxygen Barrier	Low
Sealability	Easy

Advantages:

• Economical
• Flexible and easy to fit
• Suitable for food contact

Disadvantages:

• Limited oxygen barrier
• Low UV resistance

Suitable Products: Flour, sugar, grain, plastic granules, general purpose

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2. HDPE (High-Density Polyethylene)

A more rigid liner material that is resistant to chemicals.

Property	Value
Flexibility	Medium
Moisture Barrier	Good
Chemical Resistance	High
Puncture Resistance	High

Advantages:

• Better moisture barrier than LDPE
• High resistance to chemicals
• Mechanical strength

Disadvantages:

• Less flexible

Suitable Products: Chemical powders, fertiliser, industrial minerals

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3. EVOH (Ethylene Vinyl Alcohol)

A material providing a high oxygen and aroma barrier.

Property	Value
Oxygen Barrier	Very high
Aroma Barrier	Very high
Moisture Barrier	Low (on its own)
Structure	Multi-layer

Multi-Layer Structures:

• PE/EVOH/PE (standard barrier)
• PA/EVOH/PE (high strength + barrier)

Advantages:

• Very high oxygen barrier
• Aroma protection

Disadvantages:

• Sensitive to moisture on its own; requires a multi-layer structure
• High cost

Suitable Products: Coffee, spices, food additives, aroma-sensitive products

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4. PA (Polyamide / Nylon)

Combines mechanical strength with barrier properties.

Property	Value
Mechanical Strength	Very high
Puncture Resistance	Very high
Oxygen Barrier	High
Moisture Barrier	Medium

Advantages:

• Excellent mechanical properties
• Good oxygen barrier

Disadvantages:

• Absorbs moisture
• High cost

Suitable Products: Sharp-edged products, pharmaceutical ingredients

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5. Aluminium Foil Laminate

Used when the highest barrier is required.

Property	Value
Oxygen Barrier	Very high (practically impermeable)
Moisture Barrier	Very high (practically impermeable)
Light Barrier	Complete
Structure	PE/ALU/PE or similar

Advantages:

• Highest protection against moisture, oxygen and light
• Longest shelf life

Disadvantages:

• Highest cost
• Risk of pinholes at folds
• Difficult to recycle

Suitable Products: Milk powder, enzymes, vitamins, sensitive pharmaceutical ingredients

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Barrier Performance Comparison

Actual transmission rates depend on film thickness, temperature and humidity. The table below compares the materials relative to one another:

Material	Moisture barrier	Oxygen barrier	Light barrier
LDPE	Medium	Low	None
HDPE	Good	Low to medium	None
PA	Medium	High	None
EVOH (multi-layer)	Good	Very high	None
Aluminium laminate	Very high	Very high	Complete

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Choosing Liner Thickness

Thickness is determined by the weight of the product, whether it has sharp edges, the storage time and the barrier required.

Karaca Ambalaj manufactures liners in the range of 50 - 200 micron.

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Liner Fitting Methods

1. Loose (Tubular) Liner

• Placed loosely inside the big bag
• Easy to fit
• Low cost
• May crease during filling

2. Form-Fit Liner

• Made to the shape of the big bag
• Less creasing and folding during filling and discharge
• Uses the volume more efficiently

3. Tabbed Liner (Tab-In)

• Fixed to the loops or body with tabs
• Stays in place during discharge

4. Sewn-In Liner

• Fixed to the body by sewing
• No risk of being pulled out during discharge

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Liner Recommendations by Industry

Food Industry

Product Type	Recommended Liner
Flour, sugar, grain	LDPE
Milk powder	Aluminium laminate
Coffee, spices	PA/EVOH/PE
Additives	EVOH multi-layer

Food-contact liners are expected to comply with (EC) 1935/2004 and (EU) 10/2011, and with FDA requirements.

Chemical Industry

Product Type	Recommended Liner
General chemicals	HDPE
Corrosive substances	PA/PE multi-layer
Moisture-sensitive	Aluminium laminate

Pharmaceutical Industry

Product Type	Recommended Liner
Raw materials	PA/EVOH/PE
Sensitive active ingredients (API)	Aluminium laminate

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Karaca Ambalaj Liner Options

Liner Types We Manufacture

• LDPE, HDPE
• Multi-layer barrier liners (EVOH, PA)
• Aluminium laminate
• Thickness: 50 - 200 micron

Made to Order

• To customer specification
• Loose, form-fit, tabbed and sewn-in options

Technical Consultancy

• Liner recommendation based on the product
• Selection according to storage conditions
• Balance of cost and performance

Request a technical consultation to determine the best liner solution for your application.