Shapoo bars and simple bath bars

[Giangxamar]

I have look for an answer but all I found was just recipe of shampoo bar. I really want to know what is the clearest difference between these bars so that next time I can create my own recipe. I have some concrete question:
_Why some bath bar cant be used for hair?
_What is the ingredient that cant be absent in shampoo bar?
_What is the character that make the difference in shampoo and bath bars?
Do anyone know about this?

 

[ToniD]

It is what you prefer to be in a bar, or what is good for your hair type. I used shampoo bars for a bit more than a year, and I have two friends that use them now. We all like totally different recipes. I like a bar that is softer and has a lot of lather for my hair. I also like a fairly high superfat level.

 

[dcornett]

I don't make a special bar for my hair...I use my regular bath bar for both with great results, but I've always wondered what set shampoo bars apart. I know each persons individual needs are different because even though my soap does great on my hair my daughter (who has oily hair) says it leaves her hair feeling a bit oily. I'll have to check back and see what others have to say, sorry I couldn't answer all your questions. But if there was one ingredient that "can't be absent" I'd say that would be castor oil, because it's GREAT for lather and good for your hair.