A method of waterproofing paper using an n{40 -alkyl, n{hd 1{l {40 n{hd 1{l {40 -alkylene-n,n{hd 1{l -bis-urea
Abstract
Abstract which is in situ, or subsequently, with the aid of an emulsifying agent dispersed in water. In the formula each R'' is a group such as hydrogen, methyl or ethyl, which are independently selected and which contain from zero to not more than two carbon atoms. R is generally a divalent organic radical, namely an arylene, alkylarylene, arylalkylene, cycloalkylene, or alkylene radical, which may or may not contain ethylenic double bonds. R1 is alkyl, alkenyl, aralkyl, alkylaryl, cycloalkyl or cycloalkenyl and X is independently selected from the same groups or is aryl or hydrogen. The carbon atoms of R, R1 and X combined should total at least eight and preferably not more than 52 carbon atoms. Aqueous paper sizing compositions are prepared by combining an N''-alkyl,N-substituted urea containing an isocyanate group with an alpha, beta-alkylenimine to form an (N''-alkyl),(N1''N1'' -alkylene)-N,N1-bis-urea of the formula Formula I
Inventors
- 👤 Gerhard Ewald Sprenger
Bibliographic Details
Claims Analysis
Total Claims: 2References Cited (Backward Citations)
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