Electrically conductive liquids based on metal-diphosphonate complexes

Electrically conductive liquid comprising an aqueous solution of a metal complex,

• wherein the metal complex is a complex of
• (i) one or more metals selected from the group consisting of Cu, Zn, Mn, In, Sn, Sb, Bi, Fe, Ni, Co, Ti, Zr, Nb, Y, Ce, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and mixtures thereof, and
• (ii) one or more diphosphonate ligands of the general formula (I)
• O═P(OH)2—X—(OH)2P═O (I)
• wherein:
• X=O, NR1 or CR1R2,
• R1=H, C1-C18-n-alkyl or C3-C18-isoalkyl, Cs-C6-cycloalkyl, unsubstituted or substituted benzyl and substituted or unsubstituted phenyl,
• R2=R1, —OR3 or —NHR3, and
• R3=H, C1-C4-n-alkyl or C3-C4-isoalkyl, and wherein
• the OH groups in the general formula (I) which are bonded to the two phosphorus atoms independently of each other are protonated (OH) or deprotonated (O−),
• wherein the liquid furthermore optionally comprises an additive of the general formula (II):
• R10—CHR8—CHR9—Z—(CHR4—CHR5—Z)n—CHR6—CHR7—R10 (II)
• wherein:
• n=an integer from 1 to 11,
• Z=S or O,
• R4=H, C1-4-alkyl or phenyl,
• R5=H, C1-4-alkyl or phenyl,
• R6=H, C1-4-alkyl or phenyl,
• R7=H, C1-4-alkyl or phenyl,
• R8=H, C1-4-alkyl or phenyl,
• R9=H, C1-4-alkyl or phenyl,
• R10=OH, COOH or COOR11 and
• R11=C1-4-alkyl, Li, Na, or K.

The liquid according to claim 1, wherein the liquid comprises an additive of the formula (II), wherein

• n=an integer from 1 to 3,
• Z=S,
• R4=H, methyl, ethyl, n-propyl or n-butyl,
• R5=H, methyl, ethyl, n-propyl or n-butyl,
• R6=H, methyl, ethyl, n-propyl or n-butyl,
• R7=H, methyl, ethyl, n-propyl or n-butyl,
• R8=H, methyl, ethyl, n-propyl or n-butyl,
• R9=H, methyl, ethyl, n-propyl or n-butyl,
• R10=OH, COOH or COOR11, and
• R11=K, methyl, ethyl or n-propyl.