A fabric-based item may have fabric with conductive strands of material. The conductive strands of material may include conductive yarn formed from insulating fibers and conductive fibers. The conductive fibers may be metal wires. The insulating fibers in the conductive yarn may hide the conductive fibers from view. The fabric may be woven fabric or other fabric with intertwined strands of material. The woven fabric may include conductive and insulating warp yarns and conductive and insulating weft yarns. Conductive yarn may be coupled to capacitive touch sensor circuitry and may form a capacitive touch sensor grid or other capacitive touch sensor electrode structures. Conductive yarn may also be soldered or otherwise coupled to electrical components.

A method is provided for removing silver mirroring from the surface of a black-and-white negative film by: mixing 80-100 parts by mass of triethanolamine, 0-10 parts by mass of glycerol and 0-10 parts by mass of a surfactant uniformly under stirring to produce a silver mirroring remover, where the surfactant is one or more of isomeric tridecanol polyoxyethylene (8) ether, polyethylene glycol 200, polyethylene glycol 400 or alkylphenol polyoxyethylene (10) ether; applying the silver mirroring remover onto the region of the surface of the negative film, where the silver mirroring occurs, allowing the film to stand for at least 30 minutes, and then blotting up the residual solution on the negative film; and soaking the negative film in n-butanol and cleaning it, and then blotting the residual solvent on the negative film, followed by air drying, to complete the removal of silver mirroring on the surface of the negative film.