| 摘要 |
To which NH4 salts, preferably of amino acids, and divalent phenols or monovalent phenols unsubstituted in the o- and p- positions, which are partly or wholly substituted by NH3 are added. The NH3: phenol wt. ratio is 1:3 to 3:1 and the wt. ratio of phenol to NH3 plus NH4 salt is 1:9 to 6:4. The products have improved mech. properties, and when mixed with up to 25% of fillers such as kaolin, chalk or ground stone are suitable as abrasives. |
