i need to dye some poly cotton, it takes the dye well and looks great when wet but when it dries it has these dark pink speckles all over it. i need it to be light pink what am i doing wrong, i thought i didnt‘ mix the salt in properly, but i am pretty sure i did
The problem with polyester and all synthetics is that they are basically plastic; they are nonporous and will not absorb. Microscopically, it's like the difference between a cotton woven dishcloth and a plastic colander. If you put water in the colander, it basically runs through, water on the cloth will be absorbed. Now if you put honey on the colander, you will notice that the honey will stick to the colander and coat it. (It still will not be absorbed, but it will stick.) That's the same with dyes. On a microscopic level, the dye sticks to and coats the polyester fiber. Since cotton absorbs the dye, it will always take the dye better. It's like dying your hair. If the ends are bleached, they will take the dye better while the roots will not, even if you let it set a long long time, the ends will always take more dye and be a different color. That's why it's always hard to get an even color when dying cotton blends. You could try disperse dyes which basically are built to imitate absorption by dispersing throughout the fibers to coat the deeper fibers as well as those on the very surface. Use super, boiling water. This will help the dye to penetrate the fibers and coat deeper. Instead of mixing with water, try using rubbing alcohol. 7 parts alcohol to 1 part dye. Again, the alcohol will allow the dye to coat and stick better. Added: yes, you could try heating the water to melt the salt, let it cool and mix the dye without hurting it anything.
