Paper industry

THIN STOCK PREPARATION AND WHITE WATER SYSTEMS

High-efficiency, waterfree concentrates
Due to the fact, that the consumption of water-based dispersion defoamers/deaerators in the paper- and paperboard production has been increased rapidly during the past few decades (water system closure, higher machine speed rates and therefore high white water temperatures, application of waste paper as a significant raw material source, etc.) the usage of high-efficiency, waterfree concentrates becomes more and more interesting. Consisting of 100 % active components only (no water, no emulsifiers which tend to decrease the defoaming activity) these concentrates can offer both more effective defoaming/deaeration and a significant reduction in costs and handling.

The most important properties are mentioned:

  • Very effective dosage levels at 1/2 up to 1/3 compared to the well-known water-based dispersion antifoam agents.
  • Very effective combination of both deaeration and surface-defoaming: due to the unique combination of active components, we can offer the most balanced combination of a.m. properties for each specific application.
  • Applicable at all pH-levels and temperature ranges from 30°C to 80°C.
  • Indifferent against hydrophobing agents and wet strength resins.
  • Due to the non-ionic character no effect on cationic/anionic additives.
  • Application at the usual dosage points: white water, prior to the dilution pump, thin stock cleaners etc., it is recommended to use the mentioned products undiluted.
  • Low viscosity medium, without non-Newtonian viscosity effects, i. e. easily pumpable.
  • Clear homogeneous products, no mixing in storage tank is necessary, no separation
  • At least 12 months shelf life, no danger of freeze

Dosages rates depend on the kind of paper/paperboard produced, the nature of the raw materials used, machine speed rates etc. Our technical personal is prepared to support our customer with application optimizing.


SIZE-PRESS AND COATING 

Normal and highly filled coatings
Until recently, foam build-up and air entrainment during the preparation and the application of coating formulations could quite easily be prevented with defoamers using tri-N-butylphosphate or simple esters as active components. However, in the last few years, due to increased machine speeds and the development of coating formulations with higher solid contents (> 68 % dry substance), these defoamers are not sufficient anymore. During the preparation of these so-called highly filled coatings air is entrained quite often and, due to the high viscosity of the formulation, the entrained air causes surface failures during the coating application.

As our special high solid coating defoamers are added already during the first phase of the coating preparation, they prevent the coating substance from air entrapment during the complete preparation process, thus avoiding the formation of dispersed air particles in the coating.

As the products have proven to have outstanding long-lasting defoaming capabilities, the necessity of further defoamer addition during the coating application can most often be avoided.

In general, the properties of the mentioned products are:

  • Addition during the preparation of the coating.
  • Due to the compatibility with the other coating components spot-building does not occur.
  • Outstanding long-term defoaming properties, avoiding additional dosages.
  • 100% active components only, do not contain silicones

Low dosage rates are sufficient in most situations (0,01-0,2 parts on 100 parts pigment). Exact dosage levels should be determined during evaluations in practice.

Products