Grinding of pigments
US4196016A · kind A · utility
Inventor
Key dates
| Filing date | Nov 30, 1977 |
| Grant date | Apr 1, 1980 |
| Priority date | — |
| Expiry date | Nov 30, 1997 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09B67/0001
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A method of salt grinding pigments wherein the material to be ground is milled with an inorganic salt, an organic conditioner, and larger particles such as balls or nails for comminuting the pigment to the desired state of subdivision and is subsequently recovered from the ground mass wherein the mass is treated after grinding with an organic liquid which is a solvent for the organic conditioner but which is inert to the pigment and to the inorganic grinding aid. The dispersion resulting is then centrifuged to remove solids constituting over-size pigment and inorganic grinding aid without separating the dispersed pigment particles of desired state of subdivision. The sediment is removed from the liquid dispersion of pigments and the liquid is subsequently separated from the dispersed pigment as by filtering or other appropriate means. The conditioner is separated from the liquid solvent by distillation and is returned to a succeeding batch of material along with the over-sized pigment and inorganic grinding aid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.