Jet printing of textiles with equipment based on the charged drop, piezo and bubblejet technologies, which were originally developed for paper reprographics, is now fairly common, particularly for making sample prints in a rapid response environment. However, compared with conventional screen printing, these systems impose some limitations in the number and gamut of shades that can be produced and in fabric preparation, productivity and cost. The underlying principles of the formation of the coloured pixels which make up the printed design using a jet printer have been studied both at the microscopic level and colorimetrically. A wider appreciation of the reasons for the present limitations of jet printing systems for textiles should help overcome misunderstandings between designers, specifiers and their customers alike.

Many of the principles of the relatively new science of Green Chemistry, which aims to use resources efficiently and minimise waste, are applicable in the field of textiles. Improving product quantity and reducing environmental impact in the production and subsequent coloration of textile fibres is a realistic goal. Public interest in organically produced natural fibres has followed on from that in organically grown food, although the market for organic fibres is still relatively small. In recent years, fibre manufacturers have played their part in introducing a number of more ecologically regenerated cellulosic fibres, as well as new totally synthetic polymer fibres based on renewable raw materials. The methods that can be adopted aimed at reducing the environmental impact of fibre, dye manufacture and subsequent coloration processes, are described with particular reference to these newer fibres.

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Consumers today are increasingly demanding goods which not only conform to the public’s image of being ‘eco‐friendly’ and ‘organic’ but of having been produced ‘ethically’. Meeting such high ideals has a down side, both in higher costs and often in that of having to accept more distant suppliers. Present trends in the coloration of foods with natural dyes rather than synthetic ones, increasing consumption of organic products (including fibres) and energy‐saving trends in dye application methods, fuels and lighting, as well as the means of capturing solar energy, are discussed. The discovery of some interesting and historic green colours, the wider use of green (in both senses of the word) products and green chemistry’s future role in producing them are also reviewed.

The mechanism by which the coloured image is formed by digital ink jet printing is very different from that of conventional screen printing methods and success depends on the use of sophisticated software and hardware. Some commercially available systems are listed in this paper and the basic principles of the standardisation of scanners, monitors and jet printers given. Ink jet printing machines at present available for textiles are reviewed and their limitations with regard to dye selection, shade gamuts and reproducibilty are quantified. Repeatability and shade reproducibility tests of digitally printed textiles are reported showing that improvements are required in the transformation of pattern data to the printed output.