Posted on July 20, 2017
Technological advances have changed the way we live, work, and play. From smartphones to self-driving cars, scientific advances are quickly opening up new possibilities we could not have imagined only a few decades ago. And, yet, despite the proliferation of the man-made and artificial, we are simultaneously witnessing growing interest in a return to time-honored manufacturing using natural materials. In the world of textiles, the trend toward plant-based dyes marks a profound shift in approach and process.
Since the late 1800s, man-made pigmentation sources have eclipsed natural dyes in popularity owing to their ostensibly superior qualities. But as a research cohort from Kumaruguru College of Technology writes the International Journal for Scientific Research & Development, “Environment-friendly dyes are recently enjoying a resurgence in popularity because of concerns with the carcinogenic, mutagenic, and sensitizing characteristics of many synthetic dyes.”1 According to Georgia Kalivas, who teaches in the textile department at the Fashion Institute of Technology, “the byproducts of industrial dyeing include aromatic solvents, formaldehyde, chlorine bleach, and heavy metal salts.”2. Not only can these synthetic components affect human health, but they can impact entire ecosystems via effluent produced by the textile industry, leading to significant environmental deterioration. Now, a growing number of manufacturers, big and small, are investigating the use of plant materials to create safe, beautiful dyes.
But the turn towards natural textile dyes doesn’t mean eschewing technology. Rather, a marriage between technology and the natural world is helping to perfect the creation of plant-based pigments and dyeing practices to help them compete with synthetic versions. Spectrophotometers, in particular, are playing a critical role in guiding researchers and textile manufacturers as they seek to improve environmentally responsible dye quality and performance.
Using Spectrophotometry to Expand the Color Palette
One of the primary shortcomings of natural dyes tends to be their limited color palette in comparison to synthetic dyes. In order to make natural textile dyes an attractive alternative to synthetic versions, manufacturers must find dye sources and processing techniques that compensate for this shortcoming.
While there is a broad array of traditional plant-based dyes, their color range and intensity is often not able to compete with man-made pigmentation. Additionally, as natural dyes fell out of favor, much of the knowledge regarding plant-based sources and processes has been lost due to lack of documentation and practice. As such, researchers are now looking to discover and rediscover dye sources that expand the possibilities of natural palettes and achieve a greater intensity of color. Spectral analysis is allowing experts to precisely quantify how different dyes behave and distil color quality to objective data to tailor dye formulations in ways that can approximate the qualities of synthetic dyes. The researchers at Kumaraguru, for example, employed spectrophotometry to investigate the behavior of dyes derived from forest trees to identify absorbance levels and determine how to create the most intense hues through plant-based pigmentation, a significant step toward replacing harmful dyes with eco-friendly versions.
Of course, dyes affect different types of fabrics in different ways; the material that produces a vibrant hue in wools can look muddy in a cotton textile due to the nature of the fibers. As such, it is imperative to analyze color in the precise textile type or range of textile types for which it is intended. The sophisticated optical geometries and integrated height measurement capabilities of modern spectrophotometers ensure accurate color measurement in all varieties of textile by accounting for variables such as texture and sheen.
Full article with photos available here: