Methods for obtaining colored or chromic substrates

A method for the fabrication of a halochromic wound dressing comprising:

• (i) covalently linking a functionalized halochromic dye to a carrier, comprising the steps of:
• (a) providing a carrier having a surface made up of an organic polymeric material, and, optionally, subjecting said surface of the carrier to a gas plasma pre-treatment step before performing step (b);
• (b) providing or fabricating the functionalized halochromic dye, wherein said functionalized halochromic dye comprises a halochromic dye linked to an organic moiety having a polymerizable functional group or a thiol group, wherein said polymerizable functional group is a substituted or unsubstituted alkenyl or alkynyl moiety, wherein said halochromic dye has a pKa value between 6 and 8;
• (c) applying said functionalized halochromic dye on the surface of said carrier;
• and
• (d) subjecting said surface of the carrier with said functionalized halochromic dye applied thereon to a non-thermal gas plasma treatment with an inert gas to form covalent bonds between said functionalized halochromic dye and the organic polymeric material of the surface of the carrier, thus obtaining a halochromic carrier, and
• (ii) incorporating said halochromic carrier in a wound dressing.

A method for the fabrication of a safety product for the detection of acidic or alkaline vapors comprising

• (i) covalently linking a functionalized halochromic dye to the surface of an object, comprising the steps of:
• (a) providing an object having a surface made up of an organic polymeric material, and, optionally, subjecting said surface of the object to a gas plasma pre-treatment step before performing step (b);
• (b) providing or fabricating a functionalized halochromic dye, wherein said functionalized halochromic dye comprises a halochromic dye linked to an organic moiety having a polymerizable functional group or a thiol group, wherein said polymerizable functional group is a substituted or unsubstituted alkenyl or alkynyl moiety;
• (c) applying said functionalized halochromic dye on the surface of said object;
• and
• (d) subjecting said surface of the object with said functionalized halochromic dye applied thereon to a non-thermal gas plasma treatment with an inert gas to form covalent bonds between said functionalized halochromic dye and the organic polymeric material of the surface of the object, thus obtaining a halochromic object, and
• (ii) manufacturing a safety product from said halochromic object.