I had some information up earlier that I got from an Asian online newspaper, but some of it was not accurate regarding shine and here is an update from Shapings.com. Here is the correction by Robert.
Does lycra make pantyhose shiny?
Lycra does not make it shine, you can still have a matte pantyhose with tons of lycra and it does not shine. Here is an example – Total Comfort 10 by Platino.
The shine actually comes from the shape of the nylon fibre. If the cross section is triangular then it shines, if it’s circular then it is mat as the light refraction is the key to the shine.
Thank you, Robert, for keeping an eye on my content and submitting a correction!