GRAPHENE AQUEOUS SUSPENSION FOR CONDUCTIVE INK PRODUCTION METHOD Russian patent published in 2018 - IPC C01B32/194 C09D11/52 C25B1/00 B82B3/00 B82Y40/00 

FIELD: nanotechnologies.

SUBSTANCE: invention relates to the electronics and nanotechnology, and can be used in the 2D printing. First, producing the graphene particles by the graphite electrochemical stratification, characterized by the flakes mass of about 10 mg, in the liquid phase using aqueous as the electrolyte 0.00005–0.05 M (NH₄)₂S₂O₈ solution, for 10 minutes or less, at voltage of not more than 15 V and the positive voltage supply to the graphite electrode. Resulting suspension is washed. Next, adding the graphene particles adhesion preventing additive, Trilon B or surfactant, for example, alkyl benzene sulfonic acid, or 70 % sodium laureth sulfate, or diethanolamide, or 40 % cocamidopropyl betaine. After that, proceeding to the mechanical stratification by dispersing or ultrasonic action, by centrifugation. Dispersing is carried out in the disperser mode from 2,500–20,000 rpm, inclusive, at power of 500 W for 0.5–2 h, inclusive. With mechanical stratification by ultrasonic action, centrifugation, using the 5–10 cycles, involving an ultrasonic action for about 30 min with ultrasound power from 100 to 240 W, inclusive, and subsequent centrifugation for about 30 minutes, with the rotor speed of 6,000 rpm and more. After mechanical stratification, adding the suspension stability ensuring additive, ethylene glycol, or N-methylpyrrolidone, or propylene glycol or diethylene glycol.

EFFECT: producing the suspension comprising the graphene monolayer and bilayer particles with thickness of up to 1 nm, suitable for use as the conductive ink; at that, preventing the resulting graphene particles oxidation and their adhesion.

7 cl, 5 dwg, 7 ex