As it says in the title.
Amazon is filled with such chairs
THese chairs looks like will help with ergonomics because they have a raised back but in practice the slight curve does absolutely nothing, it can't even keep a child's back straight or more than straight which is what one might assume but they completley bend back and end up just completely bending backward with the strain going back to your neck and the shoulders.
I brought these chairs back to test this and in the past few weeks I have not been able to work properly because I would get massive pains in the back of my head due to bad posture and I went back to an old steel/wood chair that is completely straight and from the moment I have sat on it, it feels very very good.