tabbie
I checked AI.
"Washing your new tea towels with vinegar before their first use is a great practice. Manufacturers often treat fabrics with chemical softeners or waxes that make the towels water-resistant. Vinegar breaks down this residue, allowing the cotton fibers to reach maximum absorbency immediately."
My new ones say they're 100% cotton.
They feel a bit shiny.
Fabric manufacturers do often apply what sewists call ‘dressing’ to materials. Naturally, this would be present on new towels and tea towels - try drying yourself on a new bath towel that hasn’t been through the washing machine!
Personally, I don’t think there’s any need to use vinegar to remove this ‘dressing’ …….just put the new tea towels through a normal, colour appropriate, wash programme.
As a side note……vinegar is great for removing the buildup of soap in facecloths. I just put about 100ml in with the normal detergent.