METHOD FOR PRODUCTION OF FIRE-RETARDANT Russian patent published in 2006 - IPC B27K3/52 C09K21/14 

FIELD: methods for production of fire-retardants for fireproofing treatment of wood materials, applicable in production of fireproof laminated products.

SUBSTANCE: the method is accomplished by interaction of carbamide-formaldehyde concentrate of the following composition, percent by mass: carbamide-21-25; formaldehyde - 54-60; water - the rest with ammonia liquor taken in equimolar relation in formaldehyde and ammonia, at heating in a weak-alkaline medium in the presence of amino alcohol added together with ammonia liquor (0.01-0.2 percent by mass) taking into consideration the carbamide-formaldehyde concentrate with a subsequent introduction of the first portion of carbamide (0.1-10 percent by mass) for 100 percent by mass of carbamide-formaldehyde concentrate, cooling, neutralization of the reaction mixture by ortho-phosphoric acid up to pH=6.0-8.0 and subsequent introduction of the second portion of carbamide (0.1-20 percent by mass), nonionogenic surface-active agent (0.01-0.1 percent by mass), potassium bichromate (0.1-1.5 percent by mass) for 100 percent by mass of carbamide-formaldehyde concentrate.

EFFECT: optimized conditions of synthesis of fire-retardants with preservation of their fireproofing efficiency at a high level.

2 ex, 1 tbl