Fabrics can acquire shiny patches if they are ironed at high temperatures, especially if the garment surface being ironed is uneven, such as a pocket or a fold line below the garment.
The shine or imprint is not permanent and will come off if you wash the garment.
You can avoid these shiny patches by doing the following:
- avoid ironing over seams or folds, or
- place a cotton cloth over the area to be ironed to avoid imprints.