'HE' Series dyes: These are bifunctional reactive he dyes which are having two reactive molties of the same type viz monochloro triazinyl. The chromogen of the colour is supported through a stilbene in the molecule. This structure provides good light fastness and as well good washing fastness because of having high molecular weight. 'HE' series dyes give good yields irrespective the m:l ratio and having high substantival. These are having high fixation and tinctorial value. All shades of 'HE' are mutually compatible in combination with good shade reproducibility. The optimum fixation temperature of 'HE' dyes is 80-85 deg c.
