Dry toners containing fanal pigments based on cationic dyes
US4869989A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 12, 1988 |
| Grant date | Sep 26, 1989 |
| Priority date | — |
| Expiry date | Apr 12, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G9/0914
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A dry toner for developing latent electrostatic images in electrostatic recording and printing methods contains, as charge-control substance, a pigment of the formula ##STR1## in which A.sup.- represents an anion of a heteropolyacid based on tungsten and/or molybdenum with phosphorus, vanadium, cobalt, aluminium, manganese, chromium and/or nickel or a copper(I) hexacyanoferrate anion, PA1 R.sup.1 and R.sup.3, independently of one another, represent hydrogen, alkyl or aralkyl, PA1 R.sup.2 and R.sup.4 independently of one another, represent hydrogen, alkyl, aralkyl or aryl, or PA1 R.sup.1, R.sup.2, R.sup.3 and R.sup.4, independently of one another, through linking to the o-position of the benzene ring, represent members of a five- or six-membered ring, or PA1 R.sup.1 and R.sup.2 or R.sup.3 and R.sup.4 together represent members of a five- or six-membered ring, PA1 B represents oxygen or N-R, PA1 R represents hydrogen, alkyl or aryl and PA1 D represents CH or C-CN, in which the two benzene rings may be fused to a further benzene ring and then hydrogen can also replace NR.sup.3 R.sup.4 and D can also denote N, and in which the cyclic and acyclic radicals and the benzene rings may be su…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.