FD&C Red 40
This gorgeous water soluble bath bomb dye is a vibrant red in water, as well as in product, depending on how much is used. (Note it does take a lot to get red in bath bombs.)
-This dye is safe for use in bath bombs, bubble bars, melt and pour soap, bath salts, etc.
-Use less for more pastel colours, use more for vibrant colors.
-Most often 1/8 of a tsp per 4 cups of baking soda is enough as our dyes are all very concentrated, but this is up to you and what you are wanting to achieve. ALWAYS TEST YOUR PRODUCT BEFORE SELLING.
-Poly 80 is NOT required for these water soluble dyes, but if you use a high amount of oil we reccommend it. Poly 80 helps mix the oils with the water so you don't have oil slicks on top of the water.
-Many people like to "bloom" their baking soda ahead of time. Blooming means adding water to the dye to make it "pop" or "come to life". Since this colour is alkaline stable this is a good option. To do this either add your dye to your baking soda and spritz with water, or add your dye to a small amount of water in a cup, mix well, then add to your baking soda. Mix very well then let dry for 24 hours. Use your coloured baking soda as you would normally.
The other option is to add your colour to a small amount of water, add your other liquids to the dye water and mix, then add to your dry ingredients and mix as you would normally.
-These are concentrated dyes so it is best to always wear gloves as particles spread easily.
- Water soluble dyes do not normally stain bathtubs unless the bathtub is lacking enamel, painted, or is scratched/coating worn off. Even then it is rare and usually too much color has been used. We have a painted bathtub that stains easily. It takes a lot of dc red 28 to stain our tub. If colours are used in reasonable amounts there should be no issues. This is also why we use poly 80 ourselves. This ensures no dye gets stuck in the oils and stick to the tub. If this happens a little bleach spray and a warm wet cloth should clear this up.
-Most dyes are light and UV sensitive. Some will fade in sunlight/UV light.
FD&C Red 40