Bulk dyeing of plastics

A process for bulk dyeing of plastics wherein a dyestuff of the formula ##STR88## wherein T represents O or N--R.sub.0

• wherein
• R.sub.0 denotes H, alkyl, aryl or acyl,
• R.sub.2 and R.sub.3 together form a radical of the formula ##STR89## wherein the bond labelled with * identifies the R.sub.2 linkage, and wherein
• X represents O or N--R.sub.16, wherein R.sub.16 denotes H, C.sub.1 -C.sub.6 -alkyl or phenyl,
• R.sub.12 represents H, phenyl or C.sub.1 -C.sub.4 -alkyl,
• R.sub.13 represents H, phenyl, C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxycarbonyl, aminocarbonyl, mono- or dialkylaminocarbonyl, arylaminocarbonyl, C.sub.1 -C.sub.4 -alkylcarbonyl, benzyl or Cl,
• R.sub.14 and R.sub.15 independently of one another represent H, Cl, C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy or C.sub.1 -C.sub.4 -alkoxycarbonyl substituents, or together form the radical of a benzo ring unsubstituted or substituted by these substituents, or
• R.sub.2 and R.sub.3 together form the radical of an unsubstituted or substituted benzo or naphtho ring,
• and
• the ring E carries a C.sub.1 -C.sub.4 -dialkylamino radical, which is substituted by Cl, phenyl, CN, OH, alkoxy, dialkylamino, alkoxycarbonyl wherein said E ring is optionally further substituted by (i) up to 2 C.sub.1 -C.sub.6 alkyl groups or halogen atoms, which are independent of one another, (ii) an acylamino-, acyloxy- or hydroxy-group, (iii) or a combination of (i) and (ii),
• or a dyestuff of the formula ##STR90## wherein R.sub.2, R.sub.3 and T have the above-mentioned meaning,
• R.sub.4 represents H or alkyl,
• R.sub.7 and R.sub.8 independently of one another represent C.sub.1 -C.sub.4 -alkyl or together form the radical of an unsubstituted or substituted carbocyclic 5- or 6-membered ring,
• R.sub.9 denotes a C.sub.1 -C.sub.4 -alkyl group which is unsubstituted or substituted by phenyl, Cl, OH, CN, alkoxycarbonyl, alkoxy, dialkylamino or alkoxy and
• R.sub.10 and R.sub.11 together form the radical of an unsubstituted or substituted benzene or naphthalene ring,
• is incorporated into a molten plastics composition or wherein the dyestuff is already added to starting components for the preparation of the plastic before the polymerization.