Abstract: A glue, substantially based on chlorolignin, for gluing cellulose materials such as wood, particle board etc. Chlorolignin, which is a waste product from the cellulose industry, is an environmentally dangerous substance. It is recovered by membrane filtering of waste liquor, separating out compounds with a molecular weight lower than 1000-2000. It is then used alone, or mixed with common synthetic glues such as melamine-formaldehyde resins, fillers, hardeners etc. Formaldehyde, paraldehyde or ammonium chloride are suitable hardeners and the chlorolignin can also be prepolymerized with formaldehyde and/or paraldehyde.