06 Jun Microfibrillated Cellulose Outside of the Box
Per Svending, Johannes Kritzinger, Tania Selina and Jon Phipps, all FiberLean Technologies Ltd.
Presented by:
Per Svending
VP Marketing
FiberLean Technologies Ltd
Renewable and recyclable material for packaging!
Global containerboard consumption growth
The corrugated box market is being transformed
- The primary function of corrugated boxes is to protect goods during transport.
- The market is huge with some 160 Mton per year of linerboard and medium made worldwide.
- Growth is broadly in line with GDP.
- Demand for PRINTED boxes is growing significantly faster and will drive a transformation of the industry.
Growing demand for printed white boxes
Key drivers:
- Support product exposure
- Regional, seasonal or target group adaption
- E-commerce
Growing demand for “Point of Sale” displays
Key drivers:
- Reducing man-hour cost for filling shop shelves
- Support product exposure
Most high quality white boxes do not rely on White Top Liner as the print surface
- Post-Print is restricted to low/no impact print methods, i.e. Flexo and Inkjet, in order not to crush the medium.
- Pre-Print offers higher quality but is more costly.
- Labeling – A pre-printed paper or board is glued on top of the corrugated board.
- Laminating – A pre-printed board or WTL is used as the top layer in the corrugated board.
- Pre-Print also allows use of other high quality print methods, such as Offset and Rotogravure.
Current approaches to white corrugated boxes
Digital printing destined to take over for packaging
- Falling average print job volume.
- Cost of digital print dropping with lower cost ink and growth in size and speed of printing presses.
- The break-even point in cost is moving rapidly.
Inkjet printing for packaging is evolving rapidly
- Wider!
- Faster!
- Higher quality!
- Pre-Print
- Post-Print
The water challenge in printing
Offset
Water from Fountain solution only
4×100% CMYK => ~ 1-2 g/m2 of water ~1% moisture in 120 g/m2 linerboard
Flexography
Water content of Ink is about 50%
4×100% CMYK => ~ 4-8 g/m2 water ~5% moisture in 120 g/m2 linerboard
Inkjet
Water content of ink is about 90%
4×100% CMYK => ~ 16 g/m2 water ~13% moisture in 120 g/m2 linerboard
Thinking outside of the box…
- MFC is a strong and sustainable binder.
- As a composite with mineral it can bring good light scattering to cover a dark base.
- The MFC-mineral composite can be tailored to an ideal pore structure.
- MFC-mineral composites are today commercially available in the kind of volumes needed for this application.
- Actually, MFC-mineral composites would be an ideal ”coating” to make White Top Liner, if it could only be run on a coater.
MFC-mineral composite coating at the wet-end
- Applied as a low solids slurry on to the consolidating base layer.
- The composite of MFC and mineral has the ability to stay on the surface without penetrating into the base.
- The top layer can be drained using existing foils and vacuum boxes.
- Pressing and drying works as normal.
- So far, the concept is proven only in pilot scale.
The composite structure prevents penetration into the base and makes wet-end coating possible
SEM pictures of a composite with 20% MFC from NBSK and 80% GCC at different magnifications.
Suitable composites can be made in relevant scale, 10 kton/year to 100 kton/year, using similar on-site co-grinding plants as “FiberLean for filler increase” as practiced by Printing & Writing paper mills.
Generic mass balance, including water, on the wire
Increased press solids with the composite on top
Similar couch solids
+3% press solids
MFC-mineral composite coating at the wet-end

Pilot paper machine samples of FiberLean on Top on Kraftliner.
The different bases used in three trials visible on the right edge
The coating has interesting properties
- High opacity for good optical coverage.
- Good adhesion and Z-directional strength.
- Excellent surface smoothness.
- Very low permeability.
- Microporous structure suitable for printing.
- Ideal for making white boxes.
Pilot scale results as a function of coat weight
Base substrate:
86 g/m2 unbleached kraft linerboard.
White Top Linerboards
White Top Liner made with MFC-mineral composite on top
Smooth and micro-porous surface
- Pilot trial run with wet-end coating made up of 20% MFC and 80% of a range of minerals
- Minerals 1, 2, 3 and 4
- Neutral and acid pH
- Internal and surface sizing
- WTL in reels for benchmark print test vs Commercial, high quality, WTL products.
- Double coated White Top Testliner (CWTTL)
- White Top Testliner (WTTL)
- White Top Kraftliner (WTKL)
Flexography printing results
Smearing overview
- Sized MFC-mineral composite coatings compared to quality White Top Liner brands.
- Smearing from 2*100% C+M wet-on-wet with printed web going through double rollers 0,3 seconds after print.
Roll to roll aqueous Inkjet printing results
MFC-mineral composite on top is well above WTL in ink density.
Roll to roll aqueous Inkjet printing results
Bleeding overview
- Sized MFC-mineral composite coatings compared to quality White Top Liner brands.
- 33% extra drying had to be applied to CWTTL to avoid sticking.
Print properties as function of pore diameter of coating
Coated WTTL and MFC-mineral composite coated WTL
MFC-mineral composite pore structure can be adjusted to optimum performance.