25-01-2023 дата публикации
Номер: EP4122661A1
The present invention relates to a process for the production of impregnated wood pieces, in particular for use in pencil production, wherein the process comprises two process stages, namelya) a first process stage, comprising- a first impregnation step, in which an untreated wood piece is at least partially, impregnated with a first aqueous impregnating solution of an impregnating agent selected from the group consisting of 1,3-dimethylol-4,5-dihydroxyethylene urea or a derivative or modification thereof, and a catalyst, and- a subsequent curing step, in which the impregnated wood piece is cured in a hot steam atmosphere at an elevated temperature above 100°C, andb) a second process stage comprising a second impregnation step, whereby the impregnated, cured wood piece is at least partially impregnated with a second aqueous impregnating solution of a wax emulsion paraffin based as an impregnating agent.The invention further relates to an impregnated wood piece obtainable by such a process and a pencil having a lead and a shaft, wherein the shaft is made from or comprises such an impregnated wood piece obtainable by such a process.
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