Functional inks designed for printed electronics

FAQ

Which substrates are compatible with VFP printed electronics inks?

VFP conductive inks are validated on PET (125-250 µm), polyimide (Kapton), polycarbonate, treated paper and PEN films. For in-mold electronics (IME) applications, stretchable variants are available for thermoformable PETG and ABS substrates. Compatibility is verified by cross-cut adhesion test (ISO 2409) and dynamic bending.

What are the recommended curing and drying conditions?

VFP silver conductive inks cure in a convection oven at 80-150°C for 15 to 30 minutes, depending on deposit thickness and substrate. For heat-sensitive substrates (thin PET, packaging films), low-temperature curing formulations (80-100°C) are available. Carbon inks dry at 80-120°C in 10-20 minutes. None of our formulations are UV-cured: thermal curing is required to develop final conductivity and adhesion.

What resistivity can I achieve with a VFP silver ink?

In standard screen printing on PET at 25 µm dry deposit, our silver inks achieve a sheet resistivity below 10 mΩ/sq. For thinner deposits (15 µm), the typical value is 15 to 25 mΩ/sq. Silver-carbon hybrid formulations provide resistivities of 100 mΩ/sq to 10 Ω/sq for applications requiring controlled resistive dissipation. All values are measured in accordance with IPC-TM-650.

Silver ink or carbon ink: how do I choose?

The choice depends primarily on the required resistivity and target cost. Silver ink is essential for low-resistance conductive tracks (RFID antennas, power circuits, current collectors): its resistivity is 1,000 to 10,000 times lower than carbon. Carbon ink is preferred for contacts, resistors and low-current signal tracks, where its lower cost and long-term stability are decisive. For membrane keypads, the standard combination is: silver tracks, carbon contacts, dielectric insulator.

What are your sample and MOQ conditions?

Samples of 100 to 500 g are available on request for qualification. Standard lead time is 5 to 10 business days. The MOQ for regular orders is 1 kg per reference for silver conductive inks, and 500 g for carbon and dielectric inks. For development projects requiring custom formulation, a co-development phase is proposed with progressive volume commitments. Contact our sales team for a personalised quotation.

Are there low temperature inks for printed electronics?

Yes. VFP develops low temperature conductive ink formulations designed for heat-sensitive substrates. The choice of ink and curing cycle depends on the substrate, the deposited thickness and the constraints of the final device.

Does VFP offer non-CMR and PFAS-free inks for printed electronics?

Yes. Depending on the grade, VFP develops non-CMR functional inks and PFAS-free technologies to meet evolving regulations and industrial formulation requirements. Regulatory characteristics should be checked in the technical documentation of each grade.

How do I choose the right ink for my printed electronics project?

The choice depends on several parameters: the electrical function, the substrate, the printing process, the maximum curing temperature, flexibility, chemical and thermal resistance, deposit thickness and industrialisation constraints. VFP Ink Technologies supports manufacturers in selecting and qualifying conductive inks, carbon inks, piezoelectric inks and dielectric varnishes, from prototype to production.