1. Commercial Manufacture and Application of Micro-Fibrillated Cellulose in Paper and Paperboard
Per Svending, Imerys Mineral AB, Sweden
September 17th 2015
Specialty Papers Conference
Milwaukee WI, USA

2. Publicised images of ”cellulose nanofibrils” show great diversity
A wide range of shapes and sizes
made through different processes
by companies, universities, and
institutes across the world.

3. FiberLean MFC and filler
FiberLean™ microfibrillated cellulose (MFC), a recent addition to the papermakers toolbox
Surface micrograph of
finepaper containing
FiberLean MFC and filler

4. The FiberLean™ MFC process
Co-grinding pulp to MFC in the presence of minerals.
The mineral acts as a very fine grinding media
Robust and reliable equipment of relevant industrial scale.
On-site manufacturing, using a minor side stream of mill pulp.
No pre-treatment of fiber required.
The FiberLean product is a MFC/mineral composite.

5. Co-grinding pulp to MFC in the presence of mineral
Relatively coarse fibrils.
Fibril length is important for wet end addition
A wide range of pulps can be used
Also flexible with regard to the mineral
GCC
PCC
Kaolin
Talc
TiO2
1 μm

6. Commercial scale experience with FiberLean™ MFC
Packaging
Coated Woodfree
Specialty + mechanical
Uncoated Woodfree
Close to 50 full scale trials on 21 paper machines to date
In Europé, North America, South America and Asia.
Trials ranging from a few hours to several days.
Extensive experience across segments
6 mills in UWF
6 mills in speciality and mechanical paper
8 mills in CWF
2 mills in Packaging
3 commercial contracts for on-site MFC plants.

7. Impact of MFC on paper strength
Tensile Burst
Bond Tear
It is possible to increase
filler by 10% or more and
suffer no strength loss.
Lab study
Mesmer recirculating hand sheets (12 sheets)
70% Eucalyptus, 30% NBSK, 550 CSF
Intracarb 60 filler

8. Impact of MFC on paper tensile
Tensile Elongation
TEA Modulus
Lab study
Mesmer recirculating hand sheets (12 sheets)
70% Eucalyptus, 30% NBSK, 550 CSF
Intracarb 60 filler

9. Behaviour of MFC in the tensile stress-strain curve
Pilot study
80% Eucalyptus, 20% NBSK, 500 CSF
Intracarb 60 filler

10. Behaviour of MFC in the tensile stress-strain curve
+ 0,6 %-units of stretch
+ 21%
Pilot study
80% Eucalyptus, 20% NBSK, 500 CSF
Intracarb 60 filler

11. Impact of MFC on paper tensile
Tensile Elongation
TEA Modulus
Lab study
Mesmer recirculating hand sheets (12 sheets)
70% Eucalyptus, 30% NBSK, 550 CSF
Intracarb 60 filler

12. Impact of MFC on optical properties
Brightness Opacity
Scattering Absorption
Lab study
Mesmer recirculating hand sheets (12 sheets)
70% Eucalyptus, 30% NBSK, 550 CSF
Intracarb 60 filler

13. Impact of MFC on other properties
Porosity Density
Initial drainage
The porosity impact can be important for hold-out of ink or coating colour.
Density can be regained by trading the positive impact on smoothness and bond strength with less intense calendering and/or use of coarser fiber, such as CTMP.
While initial drainage slows down there is a positive impact on couch and press solids.
Lab study
Mesmer recirculating hand sheets (12 sheets)
70% Eucalyptus, 30% NBSK, 550 CSF
Intracarb 60 filler

14. FiberLeanTM performance summary
Date
Title of the presentation

15. Full scale results from adding FiberLean to increase filler level in a woodfree paper
2% MFC
+8% filler
4% MFC
+16% filler
The strength of the paper
is maintained at increasing
levels of filler and MFC.

16. Based on porosity reduction
Beyond the primary target application of filler increase in P&W papers there are new product development opportunities to pursue
Based on porosity reduction
Improved hold-out of coatings
Based on strength and opacity
De-materialisation

17. Reduction in coat weight to reach a given gloss level

18. Adding FiberLean™ MFC to specialty paper at constant filler loading all chemical pulp at 250 CSF and 20% filler
To facilitate applications like this FiberLean can be supplied at up to 50% MFC content
with the balance being almost any type of mineral filler.

19. Selecting correct filler loading to reach a given opacity and strength at minimum basis weight
No filler - minimum sheet weight for required opacity
Basis weight (g/m2)
Target strength
and opacity
No filler - minimum sheet weight for required strength
No filler - minimum sheet weight for required opacity
Filler content (%)

20. Selecting correct filler loading and sheet weight with FiberLean™ Pilot paper machine data

21. Selecting correct filler loading and sheet weight with FiberLean™ Pilot paper machine data
Constant opacity

22. Selecting correct filler loading and sheet weight with FiberLean™ Pilot paper machine data
Constant opacity
Constant strength

23. Selecting correct filler loading and sheet weight with FiberLean™ Pilot paper machine data
Paper with no MFC
63 g/m2
8% filler
84% opacity
1,5 kN/m tensile
58 g/m2
Fiber
Paper with 2% MFC
53 g/m2
17% filler
84% opacity
1,5 kN/m tensile
44 g/m2
Fiber
Paper with 4% MFC
48 g/m2
21% filler
84% opacity
1,5 kN/m tensile
38 g/m2
Fiber

24. Summary and conclusions
MFC is now available for commercial use in papermaking
Filler increase in P&W paper is a key application
Several product development projects for packaging and specialty papers are ongoing
Using MFC and filler to tailor a paper grade to required opacity and strength targets with minimum material use offers one of the most exciting opportunities.

25. Acknowledgements
To my colleagues at Imerys FiberLean R&D in Par Moor Centre in the UK who have done most of the test work, and especially to Dr Jon Phipps, who designed and ran the constant opacity/strength experiments.

26. Thank you!
Source: Peter Callesen,