GEOTECH® speciality pigments for thermoplastics

Bringing pearlescence, marble and holographic effects to plastics

Geopearl® Pearlescent Pigments

Pearlescent pigments can be added to transparent resins such as PS, PP, PE and PVC to provide a gentle sheen or soft glow to the plastic. Geopearl® is a traditional mica-based pearlescent pigment which has been developed to match the lustre of natural pearls. In plastic products, it provides unrivalled elegance and a luxurious aesthetic.

Many ethical issues are associated with the use of traditional mica, however, GEOTECH is a member of the responsible Mica Initiative (RMI), which ensures that their mica is mined responsibly and ethically.

How does Geopearl® pigment give a pearlescent effect?

Geopearl® has an incredible lustre, due to a phenomenon called interference. This occurs when visible light passes through thin layers of various refractive indices.

Figure 1: The structure of Geopearl® as a backbone made from Mica which gives the pearlescent effect and then a coating of titanium dioxide or iron oxide to give a colour to the pearlescence.

The base of Geopearl® consists of natural mica in a lamellar structure. On the sides, titanium dioxide or iron oxide is used to coat the transparent flakes which make the entire structure perfect for reflecting and bending light. Accordingly, Geopearl® pearlescent pigments offer unsurpassed performance in terms of colour play and brightness.

Formulating with Geopearl®

Over 75 pearlescent pigments are available in the Geopearl® collection. The range is separated into five categories silver/white, interference, golden, metallic and colour pigments which are detailed below.

Geopearl® silver/white pigments combine pearlescent effects with reflection, lustre and transparency. Two main particle sizes are available which are 1-15 micron and 50-500 micron to create effects varying from soft/satin to a twinkling aesthetic.

Figure 2: This electric razor shows the kind of effect that can be achieved through the use of GEOTECH speciality pigments within plastic. 

For a broader colour range, Geotech® supply Geopearl® interference pigments. Various colours are available in the interference range such as gold, red, fuchsia, violet, green and blue which can be combined with other pigments, creating an endless range of shades. As three main particle size ranges are available (5-25 micron, 10-60 micron, and 10-100 micron), the effect can range from subtle silk to bright effects.

Colour travel pigments by Geotech® offer a more creative design, as these pigments change colour based on the viewing angle. Five shades are available of these pigments including red to gold, fuchsia to gold, violet to orange, blue to red and green to red.

Products such as espresso machines generally incorporate metallic pigments rather than colourful pigments to achieve a more sophisticated finish. Geopearl® offer metallic pigments composed of natural mica, coated with iron oxide, to help create this luxurious effect. Warm earth-toned colours are available in this collection such as bronze, copper, russet and warm red.

Geopearl® pearlescent pigments are temperature resistant up to 900°C, with the metallic range having a temperature resistance of up to 450°C. They comply with the regulations for plastics including food contact and provide batch-to-batch consistency. Consequently, these pigments are perfect for extrusion, co-extrusion or injection moulding and can be integrated into colour concentrates and masterbatches. Overall, this range can give effects and colour to plastics such as PVC, PE, PC, PMMA, PS, ABS and PP.

Geopearl® Crystal

Geopearl® Crystal is a range of premium quality synthetic pearlescent pigments suitable for plastic. Rather than using traditional mica, synthetic mica is used to provide a higher degree of reflectivity and colour purity. Typically, the particle sizes of these pigments are 1-15 micron and 100-260 micron. These assist in creating an array of visual effects from a matte softness to a glittering reflection.

How does Geopearl® Crystal give a pearlescent effect?

For Geopearl® Crystal the mechanism behind the pigment effect is also interference. However, unlike traditional Geopearl®, the basic structure of Geopearl® Crystal consists of synthetic mica platelets called fluorophlogopite. On either side of this, transparent flakes of titanium dioxide and/or iron oxide assist in reflecting and bending the light.

Figure 3: Geopearl® Crystal differs from Geopearl® as the Mica backbone is synthetic rather than natural. It still has the same coating for colour and interacts in a similar way with light.

Formulating with Geopearl® Crystal

The Geopearl® Crystal range consists of an incredible variety of synthetic mica-based pearlescent pigments in the categories of crystal silver/icy white/rainbow, crystal interference, crystal golden, crystal metallic and crystal colour. Similar to traditional Geopearl®, Geopearl® crystal provides batch-to-batch consistency and complies with plastic regulations. It is also produced using a calcination process hence is resistant to temperatures of up to 900 °C, and is non-toxic making it ideal for masterbatches.

Geometal®

These days, water heaters, coffee machines and toothbrushes can be designed with artificial marble effects or silver spots to add a level of elegance to the product. Geometal® is an aluminium glitter containing coloured particles precision cut from aluminium foil. It can be incorporated into colour concentrates and masterbatches to help create these marble effects. In ABS plastics for dashboards, it can also create a brilliant metallic sparkling design.

Figure 4: Geometal® can give either a marble effect or silver spots. Here the silver spot look can be seen with silver Geometal®.

How does Geometal® give an effect?

Geometal® is comprised of thin aluminium film as the base, layered with a transparent coating. Reflection of light through this transparent coating creates the colour and glitter effect observed in Geometal®. During production, the film is precisely cut to generate a broad selection of glitter sizes and sparkling effects.

Formulating with Geometal®

Geometal® is available in two colours, silver and black. For each colour, three particle sizes are available; 100 micron, 200 micron and 400 micron which are resistant to temperatures of up to 240°C. Likewise to other Geotech® pigments, Geometal® is compliant with plastic regulations making it excellent in applications such as extrusion, co-extrusion and injection moulding.

Geoglit® SP glitters

Geoglit® SP glitters are ultra-stable PET-based pigments that in contrast to aluminium glitters do not use a coating layer. They create fantastic marble effects and are available in two colours, Geoglit® SP Black and SP White.

How does Geoglit® SP give a marble effect?

A newly developed proprietary process is used to create Geoglit®. During production, the black or white pigment is directly mixed into the PET foil. For Geoglit® SP glitters the absence of any coating means they are very stable toward shear forces and have a high-temperature resistance.

Figure 5: Geoglit® SP in black within different coloured plastics to show the effects that can be achieved. Different particle sizes will achieve slightly different effects.

Formulating with Geoglit® SP

Geoglit® SP Black and SP White are available in 3 different particle sizes: 008 HEX (200 microns), 015 HEX (400 microns) and 025 HEX (600 microns). For Geoglit® SP white, a fibrous shape has also been developed to create white sparkle effects on grey or black backgrounds. All products in this range are non-toxic, compliant with global regulations for plastics and stable up to 220°C so are perfect for injection moulding.

Geofiber®

Microfibres are used as a decorative additive in various types of masterbatches such as PP, PE and ABS. In contrast to traditional glitter flakes, microfibres give a more matte, sophisticated marble effect. As a result of this, many products such as electric razors, coffee machines and waste baskets utilise these additives. Geofiber® by Geotech® are very fine, thin polyamide cellulose-based microfibres that offer various special effects in plastics.

Figure 6: Geofiber® can be used to create a subtle and sophisticated marble effect.

How does Geofiber® give a marble effect?

Geofiber® microfibres are coloured particles based on either polyamide or cellulose. During the manufacturing process, a TOW (bundle of long strands of fiber) is cut using a guillotine to produce separate particles. These particles are then classified by sieving and obtain their final visual colour through a drying process.

Formulating with Geofiber®

Geofiber® has a total of six colours in the collection. These are black, brown, red, yellow, green and blue and are available in thicknesses of 17 micron and 38 micron. In the cellulose range, Geofiber® black complies with all the FDA regulations for indirect food contact, whilst the entire Geofiber® PA (polyamide) range complies with these regulations. All Geofiber® products have a high-temperature resistance making them ideal for incorporating into masterbatches.

Galaxy®

Galaxy® by Geotech are holographic pigments that provide exclusive glitter photochromic effects. These pigments are comprised of very reflective particles and hence can offer unique, endless styling possibilities for high-end plastic applications.

How does Galaxy® give photochromic glitter effects?

Galaxy® consists of an ultra-thin film as the base with an opaque reflector layer (aluminium). This film is embossed with a very fine grating and when light diffracts on the surface a luxurious rainbow spectrum effect is observed.

Figure 7: The holographic effect from Galaxy® can be seen here with a domed plastic showing how the plastic shape changes the way the light hits the pigment and reflects it.

Formulating with Galaxy®

Incorporating Galaxy® hologram silver M is fairly straightforward as it is UV-light resistant, non-toxic, non-sensitive to friction and can withstand high temperatures of up to 400°C. It can be used in applications such as extrusion, co-extrusion and injection moulding. Also, it can be added to colour concentrates, named masterbatches, to give a hologram effect to various plastics such as PVC, PE, PC, PMMA, PS, ABS and PP.

Summary

Geotech® offers a vast array of special effect pigments that comply with plastic regulations and are resistant to high temperatures. This helps to create remarkable effects and meet the ever-changing needs of consumers. With so many different options for colours and effects, if you'd like to talk through the options for your formulations, get in contact or give us a call on 01827 314151.