Special Applications

Specialty Silica

Pigment Blacks

Special applications for pigment blacks cover all applications whose specifications go beyond coloring, UV protection and electrical conductivity. Here, the pigment black also serves as a carbon feedstock, a heat insulator, carrier system, a reinforcing additive etc.
In the special applications section you will mainly find predispersed pigment black preparations (in most cases water-based systems) that are marketed under the Derussol® brand.

Mineral systems
Mineral binding agent systems can be colored or tinted with either pigment blacks (e.g. lamp black) or Derussol® dispersions, though suitability as color stability under conditions of extensive exposure to weather has to be verified. Derussol® dispersions are also effective in improving antistatic properties while at the same time facilitating the process and avoiding dust build-up.

Polymer dispersions, emulsions and other pastes and suspensions
The increased use of water-based polymer dispersions and emulsions requires pigment black dispersions that have to be compatible (antistatic properties, coloring, tinting) and can easily injected into the process. Derussol® dispersions meet these requirements as they are available with different types of pigment black and come in different formulations with dispersing additives.
Special ceramics are just one example of an application area where Derussol® dispersions can be used as the reactive component for manufacturing carbidic materials.

Fibrous products (paper, leather, wood, glass, fibers)
Pigment blacks come with a series of properties important in applications involving these products:

• high color strength and coverage
• high temperature stability
• high light and weather fastness
• no bleeding

Depending on the application, the various pigment blacks – gas black, lamp black and furnace black – can be used to achieve the optimum specification for end-product requirements or specific fiber types (viscose, polyester, polyacrylnitrile etc.) Not to be neglected is the fact that using Derussol® dispersions greatly reduces the risk of soiling.

Molded graphite molded goods
Pigment blacks are used in manufacturing molded graphite goods such as carbon brushes, carbon connectors, carbon sanding arcs, carbon bearings, graphite kilns, graphite molds, sinter bearings, sinter molds etc.
Pigment blacks have a positive effect on the following properties of such molded goods:

• Temperature stability versus gases (reactivity)
• Thermal and electrical conductivity
• Mechanical stability
• Coating behavior
• Porosity

and thus also on durability.

Pigment Blacks for thermal insulation and in metal casting
Pigment Blacks are used for thermal insulation both in high-temperature furnaces (induction ovens for ceramics or sinter ovens for graphite mold manufacturing) and in metal foundries. Here, lamp black in powder or bead form is most commonly used.

Powder blacks show a thermal conductivity that is lower than that of beaded blacks by a factor of 3. This is offset by the significant advantages of working with beaded blacks (dosage, filling, packaging, dust build-up), so that advantages must be weighed against each other depending on the application.

Lamp black is also a favorite in metal foundry operations, where, in addition to effective thermal insulation, this pigment black also:

• blocks oxidation
• extends coquille lifetime
• binds slurry

Pigment blacks for improving porosity of flameproof materials
One important application area for low-structured furnace blacks is the manufacture of basic flameproof elements used for lining converters, electrosteel ovens and Siemens-Martin furnaces. Here, reduced coverage and penetration by the molten metal serves to extend the longevity of the stone used. The main cause for this is the reduced porosity of the stone.
When used to line waste incinerators, reduced porosity results in reduced permeability to caustic gases that would otherwise damage the steel construction (piping etc.).
Lamp black has also been used successfully in reshaped fireproof systems (e.g. gutter fillers, coating compounds, puncture plugging).

Iron Blue Pigments
Applications Properties / Suitability
Sodium ferrocyanide / YPS Further applications Sodium ferrocyanide is also used in various other areas, e.g. for curing special paper types, pharmaceutical preparations, textile dyeing, flotation additives.