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公开(公告)号:US12054001B2
公开(公告)日:2024-08-06
申请号:US17814144
申请日:2022-07-21
申请人: FABER-CASTELL AG
摘要: A process for the production of impregnated wood pieces for use in pencil production, and pencils with shafts including such impregnated wood pieces, wherein the process comprises two process stages, namely
a) 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., and
b) 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.