Impregnating agent for the thermochemical modification of wood, and process for its preparation

摘要

Impregnating agent for the thermochemical modification of wood which represents an equilibrium solution of water and alcohol and has the following chemical composition in parts by weight: water-soluble crude phenols from bituminous shale 100 urea 28-36 formaldehyde 35-40 ammonia 13-15 ethylene glycol, its homologue, or glycerol 3-10 ethyl alcohol 5-1750 water 100-3370 The process for the preparation of the impregnating agent consists in heating the mixture of 100 parts by weight of the abovementioned water-soluble crude phenols from bituminous shale, 28-36 parts by weight of urea, 3-10 parts by weight of ethylene glycol, its homologue or glycerol, 6-1025 parts by weight of ethylene glycol and 3-1492 parts by weight of water to 60-95 DEG C and obtaining an aqueous alcohol solution A; the mixture of 95-107 parts by weight of 37% strength aqueous formaldehyde solution, 54-92 parts by weight of 24% strength aqueous ammonia solution, 1-725 parts by weight of ethyl alcohol and 1-1764 parts by weight of water is kept at a temperature of 20-60 DEG C, giving an aqueous alcohol solution B. The solutions A and B are mixed at a ratio by weight of 1:1.