Pigments – colorful multi-talents

Whether it is in relation to streets, houses, garden fences or sports facilities, paints and coatings embellish and protect everyday objects. LANXESS pigments, colorants and biocides often have a part to play.

Moving on from the everyday grey

There’s no let-up in the multitude of people being drawn to the cities. Conurbations are growing increasingly larger. Whereas urban development in its early days was merely driven by the purpose of providing space, aesthetics has nowadays been assuming a greater role. Architects, therefore, are now thinking about how they can make concrete building material more attractive. In doing so, they are coming across chromophoric pigments more and more often. Whether in the form of  paving stone, roof tiling, wall coating, laminate or artificial turf, the demand is there for low-maintenance and sustainable coloured objects.
The extensive range of Bayferrox iron oxide pigments from LANXESS – with over 40 shades – and the Colortherm-brand chrome oxide pigments are making cities colorful and pleasant to live in. The color gamut extends from yellow to red, green, brown and black. More than 100 gradations of colour are available from within these color series. The most diverse building materials, such as in-situ concrete, precast concrete, concrete roof tiles, concrete paving stones or asphalt surfaces can thus be designed in an aesthetically pleasing and sustainable manner.

LANXESS brings color to cities

2_LANXESS_Eurobruggen_01-bearbLANXESS high-quality color pigments can be seen all over the world. Take, for instance, the Eurobruggen bridge in the Dutch town of Spijkenisse, near Rotterdam. Graphic designer Robin Stam had the seven fictitious bridges found on the reverse side of Euro bank notes replicated. In order to give the design of these bridges a characteristic feature, he chose concrete that is integrally coloured with Bayferrox pigments, which realistically reproduces the shade of color that the well-known bridges on the Euro notes have.
Color pigments were used as part of a redevelopment measure in urban planning in Osnabrück, Germany. Due to car traffic and heavy use as a multi-lane thoroughfare, Rose Plaza, in the Lower Saxon city, was not doing itself any credit. Over time, the rose beds that once gave the plaza its name gradually gave way to dreary colorless asphalt and concrete. Following the implementation of a design from architects Oliver Borman (yellow z urbanism architecture) and Martin Diekmann (lad+ Landschaftsarchitektur Diekmann), Rose Plaza now invites one to linger for a while longer.

3_LANXESS_Bauma_Preview_Rosenplatz_01_bearbConcrete integrally colored with Bayferrox pigments in four different shades of pink serves as the design medium for the roadway surface. Sporadically interspersed planted trees and island-like arranged green spaces combine with the integrally colored road surface to burst through the monotony of conventional road surfaces. The result is  unparalleled in Germany – both from the artistic and technological viewpoint. Thanks to  a two-layer concrete, the color scheme, which is extremely unusual for a road space, meets the high mechanical requirements set for federal highways used by heavy trucks.
“Our colour-stable and weather-resistant pigments bring long-lasting color to architecture and infrastructure. As a result, integrally colored building materials retain their visual effect and appeal even when they are exposed to weathering for long periods, and require virtually no maintenance”, says Thomas Pfeiffer, Head of Marketing & Sales EMEA, in the LANXESS Inorganic Pigments business unit.
Iron oxide pigments can be used universally in almost all paints and lacquers. A prominent example is the landmark of the French capital, Paris, the Eiffel Tower. It has been provided with coatings containing lightfast, weather-resistant and highly chemically resistant Bayferrox pigments. The combination of three different shades of brown lends the tower its unique look.

Coloring plastics

72_produktion_colorants_03_bearbColortherm iron oxide and chrome oxide pigments, specially developed for the plastics industry, are available in shades of  yellow, red, brown, black and green. There are numerous gradations of color available within the various color series. The areas of application for Colortherm range from packaging materials, tubes or connecting elements, cockpits or imitation leather in vehicles and plastics for the electronics and electrical industry, through to tartan tracks and artificial turfs for sports grounds, and wood-plastic composites (WPC). For plastic coloration, high demands are placed on  pigments. Good dispersibility has to be ensured where there are short dwell times and relatively low shear forces in the processing equipment. The pigments have to be easily dispersible and reach final tinting strength quickly, have high thermal stabilty, show no migration and have a lightfastness and a weather resistance which are adequate for the intended application. Colortherm iron oxide and chrome pigments from LANXESS meet these specifications.
For coloring break-proof and light weight PET bottles, such as for drinks or cosmetics, Macrolex dyes are suited because of their high brilliance and transparency.  These dyes from the Rhein Chemie Additives business unit of LANXESS also comply with the safety regulations for many of these applications, in particular for food packaging. With the Macrolex and Bayplast product ranges, LANXESS also provides the foundation for implementing the most diverse design concepts for mobile phones, notebooks and flat screens. From piano black for housings of flat screens to other brilliant hues, thermoplastics can be colored for such applications.
Macrolex dyes are also characterised by high thermal stability and lightfastness. In addition, they enjoy very high color strength so that very rich colors can be achieved very economically with the use of low concentrations.

Brilliant colours for interior and exterior

72_fcc_red_chair_01-bearbFurthermore, LANXESS produces Levanyl and Levanox pigment preparations using organic and inorganic high-performance pigments. They are particularly suitable for coatings and paints for interior and exterior paintings. In interior coating, the brilliance, tinting strength and hiding power of coating colours are of particular importance. The pigment dispersions used also have to be very compatible with the commonly used base systems. With Levanyl and Levanox aqueous pigment dispersions, LANXESS offers a range of high-quality, color-intensive and brilliant products, characterised by tight particle size distributions, small particle sizes and outstanding storage stability. Dispensing with volatile organic compounds (VOC) is a key criterion for keeping interior pollutants to an absolute minimum. In this regard, LANXESS products, as solvent-free and APEO (alkyl phenol ethoxylates)-free preparations, meet the highest standards.
In contrast, exterior coatings face are exposed to special loading due to  weathering and solar radiation. Particularly when cleaning, the high pH value of a base material is another factor which adversely affects the long-term stability of pigments used.  Levanox’s highly concentrated aqueous inorganic pigment dispersions are characterised by high lightfastness and weather resistance, also for outdoors areas. These are also solvent- and APEO-free and hence suitable for producing low-VOC coatings.


That’s how colors stay fresh for longer

So that the coatings also enjoy a long shelf-life, the Material Protection Products (MPP) business unit of LANXESS produces both biocidal active ingredients and biocide formulations for a broad range of applications involving paints and coatings. Among others, these include formulations for water-based wood coatings, emulsion paints and lacquers and plasters. With proven brands Preventol, Sporgard, Veriguard and Biochek, preservatives from LANXESS provide for a longer shelf-life for paints during storage by preventing decomposition by micro-organisms. In addition, further microbiocides ensure that paints and lacquers also provide long-lasting protection when applied as they prevent algal and fungal penetration of the surface.

In many European countries, architects and construction companies are legally bound to ensure buildings are free of defects. This entails protecting the surfaces of buildings from microbial coverage for a defined period. The use of biocides is indispensable in many cases in order to increase the durability of facade coatings and at the same time legally satisfy growing expectations  of the construction industry. However, the effectiveness of biocides is slowly diminishing over time.

Researchers of the MPP business unit have developed an algicide product formulation utilising modern ‘slow-release technology’, which provides for notably improved retention of the active ingredient in the colour matrix when compared with standard dry-film preservation products. Widely recognized test methods provide proof of this  superiority. Considerably smaller amounts of active ingrediants are required to achieve results which are comparable to a product using a conventional formulation technology. In many cases, only half or even a third of what is originally metered is actually needed to protect surfaces effectively against algae growth.