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.

Renewable and recyclable material for PRINTED packaging, facilitated by Nanotechnology