Process for the production of stable aqueous solutions of hardenable condensation products of melamine, thiourea, and formaldehyde and product obtained

Claim 1

A PROCESS FOR THE PRODUCTION OF STABLE SOLUTIONS OF HARDENABLE CONDENSATION PRODUCTS OF MELAMINE, THIOUREA AND FORMALDEHYDE, AND WHICH SOLUTIONS HAVE A SOLIDS CONTENT OF 40-65 PERCENT, WHICH COMPRISES HEATING MELAMINE AND THIOUREA IN A MOLECULAR RADIO WITHIN THE RANGE OF 1:0.05 TO 1:0.5 WITH FORMALDEHYDE IN AQUEOUS ALKALINE SOLUTION AT A PH VALUE WITHIN THE RANGE OF 7.0 TO 10.0, WHICH SOLUTION HAS A SOLIDS CONTENT BELOW 40 PERCENT, CONCENTRATING SAID SOLUTION BY DISTILLATION TO GIVE A SOLIDS CONTENT OF 40-65 PERCENT, THEN HEATING THE CONCENTRATED SOLUTION AT A TEMPERATURE NOT SUBSTANTIALLY EXCEEDING 100*C. UNTIL A TEST PORTION OF THE RESIN SOLUTION, WHEN DILUTED WITH WATER AT 20*C. TO A SOLIDS CONTENT OF 30-40 PERCENT, PRODUCES SLIGHT TURBIDITY, AND THEN COOLING THE RESIN SOLUTION TO ROOM TEMPERATURE AND ADJUSTING TO A PH VALUE OF 8.5 TO 10.0, THE FORMALDEHYDE IN SAID PROCESS BEING USED IN A PROPORTION SUCH THAT 0.5 TO 1.0 MOLECULAR PROPORTION THEREOF IS PRESENT FOR EACH-NH2 EQUIVALENT IN THE MIXTURE OF MELAMINE AND THIOUREA.