extrusion spun into fibres 10 and 11 bis 10 12 pentacosadiyndioic acid 1 12 dodecadiamide was separately added to ldpe 10 and pp 11 pellets and melt extrusion spun into fibres the fibres prepared in examples 6 to 11 were used to construct a non woven fabric suitable for use in the construction of a nappy sanitary towel or other absorbent pad all the textile fibres prepared above were initially colourless but on exposure to broadband uv light became blue subsequent heating converted the blue into a red colour a uv laser operating with a wavelength of 266 nm linked to an ibm compatible pc with appropriate software was used to print multi coloured text and images onto the above textiles a broadband non coherent uv lamp was used to impart colour to and in combination with a suitable mask print text and images onto the above textiles studies showed that 10 12 docosadiyndioic acid propargyldiamide and bis 10 12 pentacosadiyndioic acid 1 12 dodecadiamide had much less migration from ldpe and pp than 10 12 pentacosadiynoic propargylamide making these diacetylene more suitable and therefore preferred for this application 12 10 12 docosadiyndioic acid propargyldiamide and chp were cold patch batch applied to a variety of fabrics the fabrics were then activated using a nir source and then exposed to a uv source such as a germicidal lamp only those areas.