Insulating ink

The plastic substrate of polyethylene terephtalate (PET) Polifoil Bias is purchased from Policrom Screen. PEDOT:PSS Clevios SV3, purchased from Heraeus, serves as the electrochemically active transistor channel and gate electrodes, as well as the pixel and counter electrodes of the electrochromic displays. The electrolyte AFI VV009, which is based on poly(diallyldimethylammonium chloride) dissolved in water, solid particles providing opacity, initiator molecules and binder molecules capable of forming a cross-linked network through radical polymerization upon UV light irradiation, is provided by RISE Acreo on commercial terms. The screen printable and UV-curable electrolyte is used for both OECTs and electrochromic displays. Carbon ink 7102 and 7082 printing pastes (purchased from DuPont) are used for drain/source contacts (to minimize the reduction front) and printed resistors, respectively. To obtain printed resistors with approximately five times higher sheet resistance, and thereby lower the footprint of the printed resistors, the 7082 paste was diluted by adding ~20% of the 5036 paste from DuPont (Supplementary Fig. 7). Silver ink (Ag 5000 purchased from DuPont) and insulating ink (5018 purchased from DuPont) are used for printed interconnects and isolation, respectively.

The polyethylene terephtalate (PET) substrate Polifoil Bias is purchased from Policrom Screen. Ag 5000, DuPont Silver Ink is used for printed interconnects. Carbon ink 7102 printing paste from DuPont is used for the electrode contacts. Insulating ink (5018, DuPont) is used for electrode isolation. PQ-10, PSSNa, and BBL were purchased from Sigma-Aldrich and used as received. The P(g42T-T) and BBL inks are fabricated through a solvent exchange method. P(g₄2T-T) (30 mg) dissolved in chloroform (15 mL) is added dropwise to isopropanol (75 mL) under high speed stirring (1500 rpm) to obtain bright blue nanoparticles of P(g₄2T-T). BBL (30 mg) dissolved in methanesulfonic acid (15 mL) is added dropwise to isopropanol (75 mL) under high-speed stirring (1500 rpm) to obtain dark purple BBL nanoparticles. The P(g₄2T-T) and BBL nanoparticles are respectively collected by centrifugation (5000 rpm, 30 min) and washed in IPA six times until neutral. The neutral P(g₄2T-T) and BBL nanoparticles are re-dispersed in IPA to obtain dispersion inks (about 0.006 mg/mL for P(g₄2T-T) and 0.1 mg/mL for BBL)^{34 ,46 (link)}.