The role of colour in silicone
Written by Robbie Droman, Director of New Market Development, GSDI, Colormatrix Group
The role of colour in silicone has changed dramatically over the past three decades. The functional properties of silicone are being embraced by manufacturers and the polymer now features in increasing numbers of cosmetics, medical devices and everyday consumer items. These non-traditional applications see colour used for both aesthetic and identification purposes. The industry is opening its eyes to new possibilities for colour and custom colours and effects such as tints, glitters or even scents are growing in popularity as a result.
Colour is an art, but in silicone polymers it is also a science. Silicone colour dispersions add custom colours and effects to high consistency silicone, liquid silicone and RTVs and there are specific products available for manufacturers working within particular industries such as healthcare. Technical expertise is required to incorporate colour into silicone. Heat stability is a key factor and there are a number of variables that need to be taken into consideration when selecting a pigment. Will the pigment affect the cure system? Is the finished article post cured? Does the finished article require pigments that are FDA approved?
New uses for silicone
Non-reactive, stable and resistant to extreme environments and temperatures, it is no surprise that silicone is being used in an ever-expanding range of applications. Thirty years ago, silicone was an expensive new polymer selected only for its high level performance in extreme heat environments. From engineering parts and silicone-based coatings to kitchenware and DIY materials, its uses in today’s world are diverse. The tactile feel of silicone means it is featuring in a growing number of consumer goods. Silicone can be sterilised and does not support bacteria growth, making it perfect for medical devices such as skin tone prosthetics, catheters and grommets.
Long seen as an identification tool, colour continues to play a critical role in distinguishing specific parts in automotive, aviation or electronic devices. Uses for colour have evolved as applications for silicone have broadened and recent years have seen a growth in the number of customers looking to have their corporate identity incorporated into finished products. Protecting brand integrity is becoming ever more important and aesthetic considerations are increasingly relevant to silicone fabricators as a result. This is particularly the case for consumer goods where the success of a product often relies on the strength of a brand.
Colour considerations
Colour consistency is vital and silicone colour dispersions offer excellent pigment dispersion and high pigment concentrations. Easy to handle and quick to incorporate into products, dispersions used in liquid silicone injection moulding applications also offer suitable viscosity for metering systems. An extensive range of standard and custom colours are available for customers to choose. Typically, Pantone and RAL colours - the standard references for designers and marketers – are requested, but colours can be matched according to almost any standard.
Whether needing to make products stand out on the shelves, match the latest colour trends or ensure a corporate identity is reflected in the finished item, colour requirements can put manufacturers and brand owners under pressure. Technicians can turnaround custom colour matches in a matter of days and deliver in virtually any quantity. Colour repeatability is also a key consideration. A company may need to reproduce a colour many years later that matches the original standard to a very tight colour tolerance and exact same specification. Prosthetics is a good example of where this can be particularly important.
Tints, glitters and scents
Colour technologies are becoming more advanced and new effects are being launched. Metallic effect pigments can be incorporated into silicone to add sparkles to consumer goods, while scents can be added to items such as baby pacifiers. Tints and translucent colours are examples of new effects that are growing in popularity. Such innovations are not without their challenges, but silicone colour dispersions suppliers can work with customers to ensure that translucent colours match corporate brand guidelines, can be processed viably and meet regulatory requirements.
Technology is also advancing to cope with the requirements of specific industries. For medical applications, for example, the true healthcare colour pallet provides standard colours for both high consistency and liquid silicone. Colours are more limited than the options offered by Pantone or RAL, but it is still possible to match custom colours for both short term and unrestricted use in the human body.
Applications for silicone are continuing to evolve and, with new ideas for the polymer constantly being tested, demand for custom colours and effects will continue to rise. In future, there will be a clear need for an international outlook as companies in the United States, Europe and Asia continue to develop products. Opportunities are now global and the industry must expand its capabilities to continue to service both new and existing customers.