3 ms·

>treating the silver ink on a hot plate at 100–120C produces acceptably conductive patterns Therein lies the rub: >the ideal resistivity of the silver ink tra

by 34679 5y ago

>treating the silver ink on a hot plate at 100–120C produces acceptably conductive patterns Therein lies the rub: >the ideal resistivity of the silver ink traces would be less than 5 times that of bulk silver. >The ideal resistivities were not met, and the resistivity of the sample ink traces ranged from five to ten times the bulk resistivity. https://digitalcommons.calpoly.edu/matesp/162/ https://digitalcommons.calpoly.edu/matesp/162/

kennywinker 5y ago
Could you explain this a bit more - I think I don't quite know enough about electronics to follow the criticism. Are you saying the traces are too resistive, or not resistive enough? How would that manifest - i.e. I see working circuits on the video, but are there classes of circuits that this would not work for?
- KMnO4 5y ago
  Too resistive. Copper, silver, and gold are used because they have very low resistance. Having high resistance in the traces makes anything more complex than a few low speed components not practical.
  - zbrozek 5y ago
    There's a ton of stuff I make (especially for hobby projects) where I'm pretty sure it wouldn't really matter. I'd love to fidget with stuff like this, especially since I just acquired a wide-format inkjet printer.
- wiml 5y ago
  Too resistive, or at least, higher than what they were aiming for. You can compensate by making traces wider to get a lower resistance from the same resistivity, or by running circuits slower (digital circuit speed is often limited by the RC time constant where C is parasitic capacitance of an input somewhere — a higher-resistance trace takes longer to charge up the input gate capacitance). How hard it is to adjust for the higher resistivity will depend on the circuit, of course.
SG16 5y ago
yes that's true, liquid inks usually have more resistance and this is a drawback. This is because the ink contains non-conducting materials which are required for the right viscosity and to prevent the silver to agglomerate. These can usually be removed by heating. One can also use high intensity light to "weld" the silver particles together without damaging the plastic substrate. This requires an expensive setup but improves conductivity drastically... https://en.wikipedia.org/wiki/Photonic_curing https://en.wikipedia.org/wiki/Photonic_curing

by 34679 5y ago

kennywinker 5y ago

Could you explain this a bit more - I think I don't quite know enough about electronics to follow the criticism. Are you saying the traces are too resistive, or not resistive enough? How would that manifest - i.e. I see working circuits on the video, but are there classes of circuits that this would not work for?

KMnO4 5y ago
Too resistive. Copper, silver, and gold are used because they have very low resistance. Having high resistance in the traces makes anything more complex than a few low speed components not practical.
- zbrozek 5y ago
  There's a ton of stuff I make (especially for hobby projects) where I'm pretty sure it wouldn't really matter. I'd love to fidget with stuff like this, especially since I just acquired a wide-format inkjet printer.
wiml 5y ago
Too resistive, or at least, higher than what they were aiming for. You can compensate by making traces wider to get a lower resistance from the same resistivity, or by running circuits slower (digital circuit speed is often limited by the RC time constant where C is parasitic capacitance of an input somewhere — a higher-resistance trace takes longer to charge up the input gate capacitance). How hard it is to adjust for the higher resistivity will depend on the circuit, of course.

SG16 5y ago

yes that's true, liquid inks usually have more resistance and this is a drawback. This is because the ink contains non-conducting materials which are required for the right viscosity and to prevent the silver to agglomerate. These can usually be removed by heating. One can also use high intensity light to "weld" the silver particles together without damaging the plastic substrate. This requires an expensive setup but improves conductivity drastically... https://en.wikipedia.org/wiki/Photonic_curing https://en.wikipedia.org/wiki/Photonic_curing