Knit neckties, like the one worn by the Marquis Luca Cordero di Montezemolo on the left in the photo, make the best neckties for travel. Roll them up in a shoe and they emerge unscathed, unlike most conventional silks of my acquaintance. Black and navy blue versions, with and without dots, should be in every serious dresser's wardrobe.
Perfectly acceptable during the day, knits have the additional advantage of being slightly unexpected. The Italians call it sprezzatura. I call it smart packing.