Japanese to a relaxer?

your stylist is right. The chemical ingridient in all the Thermal Reconditioning treatments (or japanese) is Ammonium Thioglycolate (or Thio for short). Regular Relaxers contain Sodium Hydroxide. These 2 do not mix, and in fact might totally destroy your hair. If you want to stop getting your hair TR'd, you need to switch to a system that is also Thio based, such as Redken Vertical, Loreal X-tenso or Rusk Radical Anticurl. I used to  relax my hair with Rusk, and then desided to get my hair TR'd. What a nightmare that was. I decided to go back to Rusk (After my roots were long enoungh) and couln't be happier. It took my hair 2 years to recover from the desaster. If your stylist was able to do the TR on your hair with good results, she should definitly be able to do the Rusk. Is a much more simple process and hundreds of dollars cheaper. Ask your friend what kind of relaxer she used. She might have used a Thio based one, and that's why she had no problem. If she didn't, then she is one in a million, and very lucky to still have hair. I know someone who used a Sodium hydroxide relaxer just along the frontal hair line. Then decided to get TR six months later. all the hair in the frontal hair line was burned, and fell off from the roots. So listen to your stylist. You would not want to ruin your hair after all that hard work.

As far as the difference between japanese straightening and regular ones, the difference is from day to night. Totally different composition , and totally different results. Japanese systems are designed to totally and permanently straighten hair. Once the hair is treated it will defy humidity. You can sweat, work out, go out in a rainy day, and your hair stays permanently straight. Nothing and I mean nothing makes it curl or frizz after is has been blowed dried straight (in my case, since I have super curly hair). If your hair is just wavy, you won't even have to blow dry at all. With Regular relaxers, your hair will still get frizzie (less but still will) and it won't be as soft and smooth. With regular Thio ones such as Rusk, Your curls be relaxed but not totally eliminated, giving you the option to still wear your hair curlie if you want to. But when you blow dry, it will be super straight, super soft and shiny, and in my case it stays that way even in the worst humidity. No frizz at all. However it won't defy frizz. If you work out for example and sweat alot, like I do your hair will curl. I like it better than when I had it TR, since TR'd hair won't shine much even thought is super straight. If you would like more info, go to verticalsinhair.com.