According to Nice classification heading for class 23 states Yarns and threads, for textile use are include in Class 23. The heading gives you a brief broad overview about what exactly is including in a particular class.
Class 24 includes mainly textiles (piece goods) and textile covers for household use. This Class includes, in particular: – bedding linen of paper. This Class does not include, in particular: – certain special textiles (consult the Alphabetical List of Goods); – electrically heated blankets, for medical purposes (Cl. 10) and not for medical purposes (Cl. 11); – table linen of paper (Cl. l6); – horse blankets (Cl. 18).