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Self-made EL segment displays

How to make your own display with almost any configuration just using a paintbrush

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It took me three whole months and a hundred samples before I started to get something bearable. I think sometime later I will be able to write an already Comprehensive guide for the manufacture of homemade electroluminescence panels, with a detailed justification of all possible combinations of materials, but for now, I will limit myself to a description of the experiments carried out and the current results obtained of revealing the technology from 60s
  • Experiment No. 4

    Artem Kashkanov12/26/2021 at 15:17 0 comments

     Winners of the fourth experiment.

    In this experiment, I decided to grind the phosphor layer into the plane, and then immediately glued the back electrode without applying an additional dielectric layer. And lo and behold - samples No. 62 (EL-455 + EP-2146) and No. 68 (EL + 455 + Boxepox) really glow much brighter than samples No. 29 or No. 44, respectively, having the same composition, but at 3-4 times the thicker of the package:

    The composition of the samples is the same (EL-455 + EP-2146), but No. 29 has a thicker dielectric layer and was not polished

    The thickness of the package here was 70 and 150 µm for No. 62 and No. 68, respectively - therefore No. 68, based on epoxy, boxepox glows weaker

    But you can see that No. 62, based on EP-2146, is covered in stains, and on the basis of epoxy Boxepox glows very evenly.

    By the way, thermo nozzles can also be used as a substance for gluing, although the brightness will be very poor. The main thing is to glue on an electric stove so that the thermo nozzles are really liquid. Somehow I'll have to try mixing barium titanate in them and see what happens ...

    Samples glued with thermo-nozzles. The glass of No. 69 cracked during gluing, but this did not prevent it from starting at least halfway.

  • Experiment No.3

    Artem Kashkanov12/24/2021 at 17:11 0 comments

    For the third experiment, I bought three different two-component epoxy resins, which ended up with 4 binders for the phosphor and three for the dielectric layer, plus titanium dioxide and barium titanate as the filler for the dielectric layer - a total of 12 combinations. For each of them, I made 4 samples, having received a total of 48 indicators. They all worked - I turned them on on the stream on the live channel. Together with the audience, we chose one sample in each group, turned them on in parallel, and left them overnight. Until the sun rose, the brightness was kept at the same level, which is already fine

    And I got the leaders - epoxy parquet varnish and boxepox epoxy.

    The main mistake of this experiment was that I did not grind the phosphor layer, but applied a rather thick dielectric layer on top of it, and then glued it to it! As a result, the total layer thickness was over 300 micrometers! This is a lot.

  • Experiment No.2

    Artem Kashkanov12/23/2021 at 18:20 0 comments

    As part of the second experiment, I decided to play a little with the compositions, application methods, colors, and conductive glue.

    As a result, I realized that alkyd varnish cannot be used. After drying, the brightness really goes to almost zero. The likely reason is the low dielectric constant - the higher the binder has - the brighter the phosphor will glow.

    But I discovered EP-2146 epoxy parquet varnish. It gives excellent brightness, although it sins with stains. True, they cannot glue the bag together, since it will not dry out between the electrodes, and if it does dry, it will leak out; and the indicator will be covered with beautiful patterns. But it will continue to work. So for gluing the package, it is necessary to use strictly two-component compositions:

    Sample No.2 after 10 and 30 hours of gluing.

    I also found out that barium titanate must be added to the dielectric layer. It's, like a ferroelectric, significantly reduces the ignition voltage of the indicator and, therefore, increases the brightness. If, for example, you glue the indicator on a pure epoxy and epoxy with an admixture of BaTi, the second option will glow many times brighter.

    In addition, I checked that you can apply the emitting layer just with a regular brush. Especially if the phosphor is coarse, it will immediately clog the airbrush.

    And also, conductive glue can be used as a back electrode. For example, the silver-containing KONTAKTOL. Only apply in several layers and let dry:

  • Experiment No.1

    Artem Kashkanov12/22/2021 at 19:56 0 comments

    In Experiment One, I just decided to test the technology's viability.

    To do this, I mixed barium titanate in an alkyd yacht varnish in a 1: 1 ratio and applied it with an airbrush in a thin layer on a PCB strip. Then I applied a layer of a mixture of blue phosphor EL-455, again in alkyd yacht varnish in a ratio of 2: 1, and then glued conductive glass on top with a drop of alkyd varnish. This sample No. 1 worked, although, after a week of lying on the shelf, it darkened noticeably and almost completely lost its brightness. In attempts to squeeze at least something out of him, he burned out and will never shine again.

  • self-made EL Derpy Hooves

    Artem Kashkanov12/21/2021 at 19:32 0 comments

    I made four 2x7 segment displays, two lighting panels and two Derpy hooves.

View all 5 project logs

  • 1
    Step 1: Prepare transparent top layer

    ITO glass is the best solution for top plate. I use glass 50x50mm or 100x100mm with conductive layer 10-20 Om resistance

    Кinse the glass thoroughly

  • 2
    Step 2: Prepare back conductive layer

    PCB with proper etched image - is the best solution for back plate.  Double-side is better, but single-side is also ok - but you need to apply  mask when fill emitting layer.

    Use immersion gold instead of lead or HASL - to avoid any interactions between EL powder and pcb coating

  • 3
    Step 3: Apply emitting layer

    Mix the electroluminescence phosphor in epoxy resin in a ratio of 1.5: 1

    You can use ZnS phosphor or Zn2[SiO4

    Epoxy resin must be two-component and has the dielectric constant from 7 to 10. Higher is better. two-component Polyurethane also show good results.

    Apply thin layer of the mix to conductive glass. Good thickness is 50-70um

    applied emitting layer under UV light

View all 5 instructions

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