Barrier coating for use in recyclable & compostable packaging materials

Freshure® Single Coat

Barrier coating for use in recyclable & compostable packaging materials

Barrier plays a central role in producing recyclable and compostable materials needed for circular packaging. As traditional barrier solutions such as Aluminum foil and fossil based materials (e.g. PVdC and EVOH) are incompatible for use in circular packaging, there is a growing demand for environmentally friendly barrier solutions. As a biodegradable barrier solution, Freshure ® Single Coat offers a unique set of properties suitable for use in recyclable and compostable packaging materials:

High gas barrier
Transparent
Microwavable
UV barrier
Can be converted using standard printing (Flexography & Rotogravure) and lamination techniques
Much more flexible as compared with metal oxides such as AlOx
Compliant with both FDA and EU regulations
Chlorine free, Compostable and biodegradable
No effect on recyclability
Low coating weight (<0.3 g/m2) in combination with inexpensive raw materials resulting in competitive total cost of ownership

Typical oxygen barrier values obtained on polymeric films generally used in
flexible packaging are outlined in the table below:

Substrate	OTR* (cm³/m²/day) 23°C at 50% RH
BOPP (20µm)-freshure®	< 20 (1600)
PET (12µm)-freshure®	< 2 (110)
PLA (20µm)-freshure®	< 5 (800)
BOPA (12µm)-freshure®	< 1 (38)

*Numbers in the brackets indicate the OTR values of uncoated films.

Typical barrier values for Freshure® coated films in the laminated form are outlined in the table below in addition to bond strength values:

Laminate*	Barrier Values		Bond Strength (N/25mm)
Laminate*	WVTR (gr/m²/day) 23°C at 85% RH	OTR(cm³/m²/day) 23°C at 50% RH	Bond Strength (N/25mm)
PET 12µ-Freshure® //PE70µ	0.7	1.0	> 3
OPA 15µ-Freshure® //PE70µ	0.6	0.3	> 3

*Laminates are prepared using standard solventless glues.

A major disadvantage of vacuum coated inorganic layers such as AlOx is their loss of barrier upon elongation. As can be seen in below figure, oxygen barrier of Freshure® Single Coat is stable upon elongation above 6% (for comparison barrier of AlOx deteriorates above 1% elongation):