Uchida's Deco just glitter premium pens are ideal for light and dark paper and fabric. Add glitter to journals, planners, cards, paper crafting projects, t-shirts, aprons, back packs, Sneakers, denim and most fabric surfaces. No pigment/color, just glitter. Lightfast, acid free and odorless. When using on fabric: apply to prewashed fabric. Test on small area first. Dry flat overnight. Heat set recommeneded. Wash/dry on delicate cycle. Water/soap cleanup (when wet) Works best on natural fibers like cotton. Uchida recommends a small test in an inconspicuous area since all fabric types are different. Product may bleed through thinner fabrics.