Method of increasing the wet strength of paper
Abstract
Abstract A PROCESS FOR PREPARING WET-STRENGTH PAPER WHEREIN THE PAPER IS TREATED WITH A CATIONIC THERMOSETTING RESIN COMPRISES OF A WATER-SOLUBLE REACTION PRODUCT OF EPICHLOROHYDRIN AND A POLYAMIDE. THE POLYAMIDE IS THE REACTION PRODUCT OF A NITRILOTRIACETIC ACID AND A POLYALKYLENE POLYAMINE CONTAINING TWO PRIMARY AMINE GROUPS AND AT LEAST ONE SECONDARY AMINE GROUP, THE AMOUNT OF REACTANTS AND TEMPERATURE AND TIME OF REACTION BEING AS FOLLOWS: AN AMOUNT OF NITRILOTRIACETIC ACID SUFFICIENT TO REACT COMPLETELY WITH THE PRIMARY AMINE GROUPS OF THE POLYALKYLENE POLYAMINE REACTANT, BUT INSUFFICIENT TO REACT SUBSTANTIALLY WITH THE SECONDARY AMINE GROUPS; THE REACTION CARRIED OUT AT 25*-50*C. AND FOR 1-3 HOURS WHEN CARRIED OUT AT ATMOSPHERIC PRESSURE.
Inventors
- 👤 Norman W Dachs
- 👤 George M Wagner
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
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