Uncoated Paper and Board

Consumer behavior and developments in electronic media challenges the industry for higher manufacturing efficiency. Uncoated paper and board can be made from a variety of furnishes, with variable levels of mineral filler and a range of finishing processes (e.g. surface sizing and calendering). Economics through continuous process and product optimizations is a key driver in this industry.

New Discoveries for the Wet End.

The wet end is a complex dynamic system that is gaining increased attention as an area for improving efficiency, reducing effluent load and improving paper machine profitability. CALEXIS® Strength Agent is an additive designed to provide improvements in strength to allow paper and board producers multiple ways to improve economics, machine performance and end product benefits.

Improving Paper Strength

Through proprietary manufacturing techniques, CALEXIS improves paper strength by the following mechanisms.

  • CALEXIS increases the bonded area by forming bonds between fibers and other chemicals. The CALEXIS molecules set on the fiber surface, increasing the amount of active groups available.
  • CALEXIS disperses the micro fibrils increasing the specific bonding areas.
  • CALEXIS disperses and lubricates fibers, which leads to reduced frictional forces between the fibers. This leads to reduced floc size and therefore a better formation can be achieved.

The degree of effectiveness, however, depends upon correct CALEXIS product choice, which is dependent upon the individual paper and board making process, and the use of CP Kelco’s Wet End Analysis Tool.

Controlling Charge Balance

Due to its anionic nature, CALEXIS provides possibility for more efficient charge balance control.

Saving Refining Energy

When added before refining CALEXIS protects and dispersed the fibers improving the strength and uniformity of the refining result. Desired strength levels can be reached with less refining, as less damaged fibers provide better strength.

Reducing Dusting and Linting
Linting and dusting of uncoated paper can be effectively controlled with CALEXIS. This is based on the ability of CALEXIS to bind the fine fiber and filler fractions, even with low addition levels.


On-Machine and Quality Benefits

  • Savings in refining energy
  • Improved retention of cationic additives
  • Maximized filler levels
  • Incorporation of weaker or cheaper fibers
  • Control charge balance to achieve desired runnability
  • Retention adjustment
  • Improved runnability
  • Less foaming (especially in the presence of PAE)

Established Benefits to Surface Sizing

Water retention

The water retention capability of FINNFIX® CMC reduces migration of the surface sizing solution into the paper allowing both better economical performance and surface characteristics.


FINNFIX is an excellent carrier of fluorescent whitening agents (FWA) and optical brightening agents (OBA). Addition of FINNFIX to the size press will boost the efficiency of these products, giving the maximum benefit for the papermaker. graph-optical