| 摘要 |
The process comprises association of formaldehyde and melamine in the ratio 17-21:1 and reaction with an initial phase at 90-100 and with a second phase at 70-80 deg. C. The second reaction time exceeds 3 hrs. with a total time of 5-7 hrs. up to attainment of not less than 1/05 compatibility of the resin in water. - Before, during or after the reaction, plasticisers and/or stabilisers are added, for cooling of the resin, adjustment of the pH when cold to 80-100, and filtration.
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