Flame-retardant finishing of thermoplasts

Claim 1

PROCESS FOR APPLYING RED PHOSPHORUS TO GRANULES OF INFLAMMABLE THERMOPLASTS TO GIVE THEM A FLAME-RETARDANT FINISHING, WHICH COMPRISES INTENSELY MIXING THE GRANULES IN AN ATMOSPHERE OF AN INERT GAS WITH 0.5 TO 45% OF THEIR WEIGHT OF FINELY PULVERIZED RED PHOSPHORUS AND 2 TO 15% BY WEIGHT, CALCULATED ON THE PHOSPHORUS, OF A MONO-, DI-, TRIESTER OF ORTHOPHOSPHORIC ACID LIQUID AT THE PROCESSING TEMPERATURE OF FROM 10* TO 160*C HAVING AT THIS TEMPERATURE A VISCOSITY NOT EXCEEDING 1,000 CPS AND HAVING THE FORMULAE H2ROP4, HR2PO4 AND R3PO4 IN WHICH R REPRESENTS THE RADICAL OF A STRAIGHT CHAIN OR BRANCHED ALIPHATIC ALCOHOL HAVING FROM 2 TO 18 CARBON ATOMS, THE RADICAL OF A PHENOL CARRYING AT MOST THREE ALKYL SIDE CHAINS HAVING FROM 1 TO 9 CARBON ATOMS, OR THE RADICAL OF AN ALCOHOL OBTAINED BY REACTING THE ALCOHOLS OR PHENOLS FROM WHICH THE AFORESAID RADICALS RE DERIVED WITH 1 TO 8 MOLES OF ETHYLENE OXIDE, UNTIL THE TOTAL AMOUNT OF PHOSPHORUS USED FORMS A FIRM COATING ON THE GRANULES, THE RED PHOSPHORUS AND THE PHOSPHORIC ACID ESTER OR ESTER MIXTURE BEING APPLIED TO THE GRANULES ONE AFTER THE OTHER IN ANY ORDER OF SUCCESSION.