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MANUFACTURE OF SELF-DETAILED PHOTORESISTORS
Photoresistor based on gelatin also potassium dichromate
15 g of gelatin to pour 60 ml. Boiled water will also leave for swelling for 2-3 hours . Later, swelling gelatin put the container on a water steamer at a temperature of 30-40 degrees until the gelatin is completely dissolved.
In 40 ml of boiled water dissolve 5 g of potassium dichromate (chrome powder, bright orange powder), Dissolve in low light.
Pour the other into the main solution with vigorous stirring. Add a few drops of ammonia to the stubble obtained by pipetting until a straw color is obtained.
Before applying a layer on the board, it must be carefully prepared - to process the "nouveau" is also good to degrease.
The photo emulsion is applied to the prepared reward by the irrigation route, or by a soft brush in very low light. The remuneration is dried up to "detach" at room temperature.
The dried template is applied to the dried fee (by drawing to the board) also pressed with a piece of thin glass.
Later, the exposure (in low light) is rinsed in warm running water until the gelatin is removed. In order to better estimate the result, it is possible to color the non-removed sections with a solution of potassium permanganate.
17d. Joiner's glue, 6g. 100ml. Water, 3ml. The aqueous solution of ammonia is left to swell for a day, but then heated on a water steamer at t 80 ° C until the solution is completely filled.
2.5g. Potassium dichromate is also 2.5 g of ammonium dichromate , 3ml. Aqueous ammonia solution, 30ml. Water 6ml. Alcohol.
At which time the main solution will cool down to 50 ° C , with vigorous stirring, pour in the other solution in it another filtered (this also needs to be done in a darkened room, sunlight is inadmissible!)
The emulsion is applied at a temperature of 30-40 ° C. Further as if in the main recipe.
Photoresistor based on ammonium dichromate and polyvinyl alcohol
Prepare the solution:
Polyvinyl alcohol - 70-120 g / l
Ammonium bichromate 8-10 g / l , Ethyl alcohol 100-120 g / l.
Avoid bright light!
It is applied in 2 layers:
The first layer - drying 20-30min. At t = 30-45 ° C.
Second layer - drying 60min. At t 35-45 ° C. It appears as if it were also in the first one.
Developer - 40% alcohol solution