ENGOBE Russian patent published in 2013 - IPC C04B41/87 

FIELD: chemistry.

SUBSTANCE: invention relates to ceramic building materials and can be applied in engobing of brick, tiling, tile. Engobe contains Cambrian clay, broken glass and neutralised galvanic sludge with humidity 80% with the following ratio of components, wt %: Cambrian clay 34.0-36.0; broken glass 14.0-20.0; neutralised galvanic sludge with humidity 80% 46.0-50.0. Galvanic sludge is product of purification of galvanic production sewage waters and consists of molecular and colloidal particles of chromium, iron, nickel, copper, zinc hydroxides, as well as phosphates and sulfates. Engobe has brown colour.

EFFECT: increased impact strength of engobe.

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