Formulation containing a highly branched polymer, highly branched polymer and electro-optical device containing this highly branched polymer

A formulation comprising

• A) at least one highly branched polymer which contains
• 30 to 70 mol % of at least one hole-transporting recurring unit A selected from triarylamine units of the following formula (A)
• where
• Ar1 to Ar3 are on each occurrence, in each case identically or differently, a mono- or polycyclic, aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R;
• R is on each occurrence, identically or differently, H, D, F, Cl, Br, I, N(R1)2, CN, NO2, Si(R1)3, B(OR1)2, C(═O)R1, P(═O)(R1)2, S(═O)R1, S(═O)2R1, OSO2R1, a straight-chain alkyl, alkoxy or thioalkoxy group having 1 to 40 C atoms or a branched or cyclic alkyl, alkoxy or thioalkoxy group having 3 to 40 C atoms, which may in each case be substituted by one or more radicals R1, where one or more non-adjacent CH2 groups may be replaced by R1C═CR1, C═C, Si(R1)2, C═O, C═S, C═NR1, P(═O)(R1), SO, SO2, NR1, O, S, or CONR1 and where one or more H atoms may be replaced by D, F, Cl, Br, I or CN, or a mono- or polycyclic, aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which may in each case be substituted by one or more radicals R1, or an aryloxy or heteroaryloxy group having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R1, or an aralkyl or heteroarylaralkyl group having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R1, or a diarylamino group, diheteroarylamino group or arylheteroarylamino group having 10 to 40 aromatic ring atoms, which may be substituted by one or more radicals R1, or a crosslinkable group Q, where two or more radicals R may also form a mono- or polycyclic, aliphatic, aromatic and/or benzo-fused ring system with one another;
• R1 is on each occurrence, identically or differently, H, D, F or an aliphatic hydrocarbon radical having 1 to 20 C atoms, an aromatic and/or heteroaromatic hydrocarbon radical having 5 to 20 C atoms, in which, in addition, one or more H atoms may be replaced by F;
• where two or more substituents R1 may also form a mono- or polycyclic, aliphatic or aromatic ring system with one another;
• and the dashed lines represent bonds to adjacent structural units in the polymer,
• wherein Ar3 is substituted by Ar4 in at least one, of the two ortho positions, where Ar4 is a mono- or polycyclic, aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which may be substituted by one or more radicals R,
• 5 to 30 mol % of at least one branching recurring unit B,
• 5 to 30 mol % of at least one further recurring unit C selected from 4,5-dihydropyrene derivatives, 4,5,9,10-tetrahydropyrene derivatives, fluorene derivatives, 9,9′-spirobifluorene derivatives, phenanthrene derivatives, 9,10-dihydrophenanthrene derivatives, 5,7-dihydrodibenzoxepine derivatives and cis- and trans-indenofluorene derivatives, 1,2-:
• 1,3- or 1,4-phenylene, 1,2-, 1,3- or 1,4-naphthylene, 2,2′-, 3,3′- or 4,4′-biphenylylene, 2,2″-, 3,3″-, or 4,4″-terphenylylene, 2,2′-, 3,3′- or 4,4′-bi-1, 1′-naphthylylene or 2,2′″-, 3,3′″-, or 4,4″′-quaterphenylylene derivatives, and
• 5 to 40 mol % of at least one end group E,
• where the recurring units A, B and C are different from one another, wherein the highly branched polymer has a molecular weight Mw in the range from 25,000 to 500,000 g/mol, and
• B) at least one organic solvent having a boiling point of at least 200° C.,
• wherein the formulation has a viscosity of from 2 to 20 mPas.