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Old 12-02-2017, 06:19 PM
Jordan Kube Jordan Kube is offline
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Encapsulated Cd-Se stains

These are the first results experimenting with encapsulated cadmium selenium stains in soft glass. I did some consulting work for a colored borosilicate glass manufacturer in September 2017 and saw some pretty impressive results with these compounds. The ceramics industry moved to this type of coloring for these chemicals a long time ago and could it be huge if this works in soft glass. The documentation I've read suggests 1000 times less emissions and finished glazes that are food safe.

This first experiment was done fairly loose just to give me a base line. Would any color show? If so what and how? I have about 24 of these stains and I chose 5 based on my interest in the color, mostly reds.

I used spectrum regular clear glass fritted into water out of the furnace. I mixed 200 grams clear with about 5% of each colorant. The crucibles were then filled with this mixture and brought up in my kiln to 2150 from room temperature. The kiln was held at temperature for 10 hours, a time I thought reasonable to give the fritted glass enough time to fine out. The crucibles were then cut in half and polished to better see the results.

The colors from left to right:

11.8g 4254 voilet Cr-Sn-Zr
11g 50779 Blood Red Zr-Si-Cd-Se
11.83g CT-1807 Strong Red Zr-Si-Cd-S-Se
10.34g 279615 Red Zr-Si-Cd-Se
10g 50669 Fire Engine Red Zr-Si-Cd-Se

The violet is interesting if one could get it to turn the color as seen at the top of the crucible, otherwise what it shows here in the glass can be achieved with cobalt and copper compounds.

The next step is to mix the stains into milled or powdered glass as the boro guys do and charge into a crucible that is already at temperature, as one normally would. I imagine base glass composition is important and there is literature giving some guidelines for glazes that I'm sure would apply to glass compositions as well. Proper ratios or absence of zinc, calcium, magnesium, etc.

I have a feeling mixing these into raw batches might not show results as good as these but I am purely speculating. If that is the case, custom clears could be melted and milled before additions were made.

Stay tuned.
Attached Images
File Type: jpg Encapsulated cad sel resize.jpg (89.8 KB, 66 views)
File Type: jpg Encapsulated cad sel info resize.jpg (80.9 KB, 39 views)
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