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公开(公告)号:DE2358856A1
公开(公告)日:1975-05-28
申请号:DE2358856
申请日:1973-11-26
Applicant: BASF AG
Inventor: DIEM HANS DIPL CHEM DR , LIBOWITZKY HERBERT DIPL ING DR , MATTHIAS GUENTHER DIPL CHEM DR , DUDECK CHRISTIAN DIPL CHEM DR , LEHMANN GUNTER
IPC: C07C45/00 , C07C45/86 , C07C47/058 , C07C67/00 , C07C47/04 , C07C45/24 , C07D251/48
Abstract: 1480921 Stabilizing aqueous formaldehyde BASF AG 25 Nov 1974 [26 Nov 1973] 50896/74 Heading C2C Aqueous formaldehyde solutions are stabilized by means of a bis-guanamine of formula wherein the two substituent on the phenylene ring are in m or p-position to each other. 0À001 to 0À5% by weight of stabilizer may be used and the formaldehyde solution may contain 28-65% by weight of formaldehyde. The stabilizer may be added as a stock solution in a formaldehyde solution of higher strength than that to be stabilized and having a pH of 2À5 to 5À8 and the latter is preferably kept at 40-80‹ C. for 10-30 hours before adding the stock solution.