Method of flameproofing wood with inorganic ammonium salts and dicyandiamide/formaldehyde reaction products
AssigneeCiba-Geigy Corporation
InventorsPeter Rohringer, Hans Wegmuller
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Abstract
A process for flameproofing wood is claimed, which comprises treating the wood with aqueous preparations which contain (a) at least one water-soluble ammonium salt of a non-volatile inorganic acid, e.g. ammonium sulfate or ammonium phosphate, (b) at least one water-soluble cationic reaction product of dicyandiamide, formaldehyde, optionally an ammonium salt and/or an alkylenepolyamine containing at most 18 carbon atoms, or the acid salt thereof. Components (a) and (b) are applied in succession or preferably simultaneously and the wood is subsequently dried. The flameproof finish obtained is resistant to rinsing. The wood provided with the flameproof finish is used in particular as mine timber.
Claims9
A process for flameproofing wood, which comprises impregnating wood with aqueous preparations containing
- (a) 50 to 300 g/l of a water-soluble ammonium salt of a non-volatile inorganic acid, and
- (b) 3 to 300 g/l of a water-soluble cationic reaction product of
- (b.sub.1) dicyandiamine;
- (b.sub.2) formaldehyde or formaldehyde donor;
- and at least one of
- (b.sub.3) an ammonium salt, or
- (b.sub.4) an alkylenepolyamine containing at most 18 carbon atoms, or the acid salts thereof,
- and subsequently drying the wood.
Dependencies are inferred from the claim text.