We present some bialgebras and their monoid of characters. We entend, to the case of some rings, the well-known theorem (in the case when the scalars form a field) about linear independence of characters. Examples of algebraic independence of subfamilies and identites derived from their groups (or monoids) of characters are *provided. In this framework, we detail the study of one-parameter groups of characters. It is a joint work (arXiv:2009.10970) with Darij Grinberg (Drexel Universiy, Philadelphia, US / currently Germany) and Hoang Ngoc Minh (LIPN, Paris XIII University).