| abstract |
The invention relates to modified alkali or ammonium humates by oxidation of compounds according to the general formulas are prepared, wherein R₁, R₃ and R₄ are identical or different and represent an OH group or hydrogen, R₂ represents a CO or CH₂ group and R₅ and R₆ are identical or different and represent hydrogen, an OH group or methoxy group, where R₄, R₅ and R₆ are not all hydrogen at the same time. |