CURRENT-CONDUCTING PASTE FOR LOW-TEMPERATURE SINTERING AND METHOD OF PRODUCING CURRENT-CONDUCTING PASTE Russian patent published in 2025 - IPC H01B1/24 

FIELD: chemistry.

SUBSTANCE: invention relates to conductive paste and method of its production and can be used for production of electroconductive layers by method of screen printing in production of silicon solar cells, flexible displays, elements of electric circuits of printed electronics. Paste contains fine silver powder with a degree of purity of not less than 98% and particle size of 1-10 mcm and an organic binder from 5 to 35 wt.%, wherein the organic binder used is alpha-terpineol. Silver powder is pre-treated with a surfactant to prevent agglomeration of silver microparticles, ratio of components used in conductive paste is: silver powder – from 65 to 95 wt.%; organic binder – from 5 to 35 wt.%; surfactant – from 0.1 to 5 wt.%. Method involves addition of a solvent and a surfactant to fine silver powder with particle size of 1-10 mcm, which prevents agglomeration of silver microparticles, and subsequent ultrasonic treatment for 60-90 minutes. Isopropyl alcohol can be used as a solvent. After ultrasonic treatment, the solvent is removed to obtain a dry substrate. Solvent can be removed in a rotary evaporator at temperature of 40-50 °C. Organic binder is then added to the substrate and the obtained composition is homogenised for 120 minutes, followed by ultrasonic treatment for 20-30 minutes.

EFFECT: elimination of agglomeration of silver microparticles during production of current-conducting paste, reduction of porosity of sintered current-conducting layer and increase of electrical conductivity, ensuring purity of the sintered layer due to exclusion of carbon residues from the organic binder, exclusion of the effect of the current-conducting paste and the sintered current-conducting layer on the silicon plates.

5 cl, 1 tbl, 1 ex