It can. The chemicals can damage your hair and remove its elasticity, changing your curl pattern. Use lots of hydrating products after you color it. Oils, butters, deep conditioners.
Will dying hair cause you to loose or change your curl pattern..What should You do after dying it?
I baby my hair after I color it. I leave it alone for a couple days after, then hit it with deep conditioner and my fave hydrating oils, like jojoba or olive.
I have experienced this first hand. With all over permanent color, my curl patterns changed and especially if I hit the salon versus at home color.
Depending on what look/color you are going for, try something 100% natural like Henna Powder. This is a natural plant that has organic dyeing agents in it, which can turn the darkest curl into a reddish tone. If you don't want red, opt for a natural lifter after your henna powder treatment with honey, cinammon, and water. Let it soak your hair from root to tip for about 45 minutes to an hour. This will turn your curls golden brown. It's a safer alternative to at-home or salon hair dye.
I would say research henna, I haven't tried it but as Devri1 said its can work to dye hair. I heard good and bad things about it so thats why I said research it. I colored my hair and I used a box color by Clairol texture and tones. After I colored, I made sure to deep condition my hair. I left it on for about an hour or so but as curlycoriander stated, you should use hydrating products because the hair could become dried out after color.
I have never noticed any curl pattern changes, my hair is usually softer and more shinny after I dye it. I use a box from the store, usually garneir nutries but had good results from others too