Photoactive materials

A diamine compound represented by the general formula I:

• wherein A1 and A2 each independently represent a group represented by general formula II:
• wherein
• C1 to C3 each independently represent an aromatic or an alicyclic group, which is unsubstituted or mono- or poly-substituted by a cyano group or by halogen atoms, or by a cyclic, straight-chain or branched alkyl residue which is unsubstituted, mono- or poly-substituted by fluorine, chlorine, having 1 to 18 carbon atoms, wherein one or more non-adjacent —CH2— groups may independently be replaced by a group B;
• D represents a hydrogen atom, a halogen atom, a cyano group, or a straight-chain or branched alkyl residue which is unsubstituted, mono-substituted by cyano or fluorine, chlorine, or poly-substituted by fluorine, chlorine, having 1 to 24 carbon atoms, wherein one or more non-adjacent —CH2— groups may independently be replaced by a group B, or represents a organic group having a steroid skeleton;
• S1 represents a single bond or straight-chain or branched alkylene group which is unsubstituted, mono or poly-substituted by fluorine, chlorine and cyano, having 1 to 24 carbon atoms, wherein at least in A1 or A2:
• one —CH2— group is replaced by —CH═CH—, and
• wherein one or more —CH2— groups is independently be replaced by —CO—, —CO—O—, —O—CO—, —NR1—, —NR1—CO—, —CO—NR1—, —NR1—CO—O—, —O—CO—NR1—, —NR1—CO—NR1—, —CH═CH—, —C≡C—, —O—CO—O— and —Si(CH3)2—O—Si(CH3)2— and wherein R1 represents a hydrogen atom or lower alkyl;
• Z1, Z2 each independently of the other represent a single bond or a spacer unit which is a straight-chain or branched alkylene group which is unsubstituted, mono or poly-substituted by a cyano group or by halogen atoms, having 1 to 8 carbon atoms, wherein one or more non-adjacent —CH2— groups may independently be replaced by a group B;
• n1 to n3 are each independently 0 or 1;
• and
• B represents a group selected from —O—, —CO—,
• —CO—O—, —O—CO—, —NRS—, —NRS—CO—, —CO—NR1—, —NRS—CO—O—, —O—CO—NRS —, —NR1—CO—NR1—, —CH═CH—, —C≡C—, —O—CO—O— and —Si(CH3)2—O—Si(CH3)2— and wherein R1 represents a hydrogen atom or lower alkyl,
• with the proviso that if n1=n2=n3=0 then D is a straight-chain or branched alkyl residue which is unsubstituted, mono-substituted by cyano or fluorine, chlorine, or poly-substituted by fluorine, chlorine, having 5 to 24 carbon atoms, wherein one or more non-adjacent —CH2— groups may independently be replaced by a group B, or represents a organic group having a steroid skeleton.