Depsafesp

In the summer, dust and smoke from forest fires often comes in through the windows of my house. They have screens, but the screens are only to keep insects out; the holes are much larger than the dust and smoke particles. Therefore, I would like the screen to act as an electrostatic precipitator. I'm pretty sure that idea isn't new, but how do you assemble said electrostatic precipitator window screen?

Start with a frame, where each side of the frame is electrically conductive but isolated from the two sides with which it shares corners. String wires across from one side to the other, such that the horizontal and vertical wires are in different planes. In other words, the wires are attached to both the front and back of the frame, but on the front they're all horizontal (attached to the left and right frame members) and on the back they're all vertical (attached to the top and bottom frame members). Make the separation between the two planes small, like a millimeter or less. Now, if you connect high voltage to the two planes (one positive and one negative) it will act as an electrostatic precipitator.

However, it will not be very durable, it could short out if something pushes on it, and an insect could squeeze through by pushing the wires apart (when the HV is turned off, anyway). So we need something to hold the wires in place.

To accomplish that, put the screen as built so far into a vat, and fill the vat with a special liquid. The liquid consists of a photopolymer resin (i.e. something that will become solid when exposed to ultraviolet light) and a solvent. The resin molecules must be more electrically polarizable than the solvent molecules. Then apply a voltage to the screen, as before, except it may be an AC voltage now. This will cause the resin molecules to assemble themselves between the two planes of wires, where the wires cross over each other.

Then, very carefully, lift the screen out of the vat while maintaining the voltage (to hold the resin molecules in place), and allow the excess resin and the solvent to drip off/evaporate. Then expose the screen to UV, and turn off the voltage. Now you have a screen where the horizontal wires and the vertical wires are in different planes, but with a tiny plastic support attached at each intersection. Now you can use this as an electrostatic precipitator in your window.

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