While we are often eager to look out for potentially revolutionary discoveries in terms of fresh new materials, the substances that we have been exposed to for decades seem to attract less of our attention. However, in light of the current cultural emphasis on reuse and revival it comes as no surprise to learn that materials are subject to the same rejuvenations and make-overs that occur worldwide at the start of a new year.
Cellulose acetate (CA), a thermoplastic from the cellulosics family, this year celebrates its 110th ‘birthday’, but instead of being consigned to the backs of our minds the material has recently been propelled to the forefront of cutting-edge creativity.
History of Cellulose Acetate
The history of cellulose acetate can be traced back to 1865, when Paul Schutzenberger was responsible for first preparing it, but it was not until 1894 that a method for its production was created by Charles Cross and Edward Bevan. Ten years later, it was found that partially hydrolose CA could dissolve in acetone, prompting brothers Camille and Henri Dreyfus (Swiss brothers whose trademark product, Celanese, is still manufactured as a fibre for use in fashion garments) to create CA films and lacquers that were used during World War 1 for waterproofing and stiffening the fabrics used to cover aeroplane wings.
Processing Properties and Applications of Cellulose Acetate
Since then CA, which is formed by the reaction of cellulose, acetic acid and acetic anhydride, has featured strongly in the textiles and clothing industries. It has also traditionally been used for applications such as extruded tape, packaging, rigid transparent containers and electrical insulation, which benefit from the combination of endless mouldability, toughness and low thermal conductivity that characterise all cellulosics. These factors unite to create a highly versatile material, and it is precisely this versatility that has prompted manufacturers to promote its resurgence.
Reinventing Cellulose Acetate
One such company is Eastman, an American chemical production business with a speciality plastics division, who has been prompted to invest in bringing CA into the 21st century. Eastman began producing cellulose esters in 1930, but recent economic disquietude and mounting concerns surrounding the industry’s future growth drove the company to seek creative help from innovation strategists IDEO. Working from a brief that requested a reinterpretation of copolyester and cellulose (including CA), IDEO produced the collective vision project, which moves away from the traditional perception of these materials as being functional and uninspired, and instead envisages them as dynamic, original and highly modern.
Showcasing the unique characteristics of CA, and providing an opportunity for the material’s design possibilities to be rediscovered, the venture presents CA as a material that is yet to be fully fatigued in terms of potential future applications. The project uses copolyester and cellulose in a range of conceptual pieces of eyewear, which not only act as tangible representations of previously unexplored routes for materials use, but also embody the vision and foresight that is paramount to innovation.
Cellulose Acetate in Sunglasses
The application of cellulosics to spectacle production is not necessarily new - the material was used to create the faux tortoise-shell designs that were popular in the 1980s - but the aesthetic qualities have been given a contemporary twist. This interaction between old and new can be noted in ‘Ensemble’, sunglasses with a range of accessories that couple modern technology with colour choices inspired by the 1970s. In another example of reinvention, ‘Extreme’ blurs the line between sportswear and fashion, moving away from the image that plastics are mass produced and soulless, instead emphasising the quality and individuality that can be obtained through CA use.
Figure 1. Contemporary sunglasses design using cellulose acetate.
This is not necessarily where Eastman plan to go in terms of future production, and the Collective Vision range is only conceptual, but it certainly satisfies the company’s objective of encouraging a wide audience to regard CA as a material that facilitates high-end design. By moving away from the notion that CA is purely functional, and promoting the material as something that can instead be regarded as aspirational, Eastman has reshaped the mould that CA was cast in, paving the way for a future where cellulosics are no longer overlooked.
Source: Materials World, Vol. 12, No. 1, pg. 22, January 2004.
For more information on this source please visit The Institute of Materials, Minerals and Mining.