One of our most frequently asked questions is what colours to use for certain products.
So here is part 3 of our quick guide to using colourants by product, this week we look at Bath Bombs and dry toiletries.
You can find part 1 colour, cp soap here
Part 2 colour, melt and pour soap here
There is no definitive usage rate for colours in cosmetic products. How much you add depends on a number of factors, including the type of colourant and the recipe used. The depth of colour will vary with the amount added. Start off with a few drops and build up to the required colour, remember to keep a note of how much you used ready for next time.
Colouring Bath Bombs & Dry Toiletries
When choosing a suitable colour for bath bombs the main thing to remember is that it needs to be stable in acid environments. So before you make a large batch always test your planned colourants in a small batch.
Mineral pigments have high tolerance to acid and alkali (with a few exceptions), and generally they give pale colours to bath bombs. Although they are synthetically produced, they are “nature identical”, meaning they have the same molecular makeup as the once mined pigment from the earth. Insoluble pigments are not intended for use in bath bombs or dry toiletries.
- Ultramarines and oxides are powdered pigments and very strong, a little goes a long way.
- Pigments will give pale pastel colours, do not be tempted to add more to the mixture in increase colours, you risk staining the bath and towels.
- Add a little colour at a time and mix in well.
- Ultramarine blue is not suitable in acid environments such as Bath Bombs where citric acid will produce sulphur dioxide gas.
Water Soluble Dyes (powder/granules/liquid) have small particle size and lend their colour to products by solublising. Some dyes are less tolerant of extreme pH environments than others which means that not all are suitable for use in acid products like bath bombs. Dyes should always be used sparingly and never added to any dry toiletries in their powdered form. Dyes are synthetic and are not considered natural or “nature identical”.
- If bought in powdered form it will need to be diluted in water, to make a concentrate use a maximum of 5% by weight in 95% water. When diluted in water, dyes often appear a different colour from that of their concentrated liquid or powdered forms.
- Blues tend to fade quickly in acid products
- As they are liquid they can cause the bath bomb mix to bubble, so mix in quickly and thoroughly.
- Some of the names can be confusing; labels such as D&C mean it’s suitable for drugs and cosmetics, FD&C means it can also be used in food.
Natural Dyes are similar to synthetic dyes in that they have small particle size and lend their colour to products by solubilising, but they are derived from natural sources as is evident from many of their descriptions. Some dyes are less tolerant of extreme pH environments than others which means not all are suitable for use in bath bombs
- Natural Dyes can come in powdered, granular or liquid form. When dilute or further diluted in water, dyes often appear a different colour from that of their concentrated liquid or powdered/granular form. Dyes should always be used sparingly and never added to any dry toiletries in their powdered/granular form.
Natural Colours (Spices & Botanicals)
Dried botanicals are a great way to decorate bath bombs giving them a great natural finishing touch. Unfortunately many will fade quite quickly.
- The list is endless but a few to try are:
- Spices, like Ground cinnamon Paprika and Turmeric
- Cocoa, coffee and Green tea powder
- Seaweed & Algae. Kelp, bladder wrack and spirulina as well as using for their concentration of minerals and nutrients can also add colour and texture.
- Fruit & Flower powders, such as cranberry, rose and lavender
Coloured Micas are fine pigment-coated mica powders which can be used in bath bombs but have a tendency to float on top and then cling to surfaces such as the bath itself or your skin. A better alternative are Coated Mica Pigments which differ from regular mica in that their coating allows the mica to freely suspend in water.
- Coated micas give brighter richer colours than mineral pigments.
- Can be added to the mixture as a powder, can be also be added to the mould for highlighting detail before adding the bath bomb mixture.
- Mica is considered natural but the type of colour used would determine if it is synthetic or natural. Dye coloured mica is synthetic, pigment coloured mica would be synthetic but “nature identical”, meaning they have the same molecular makeup as the once mined pigment from the earth.
Cosmetic Glitters and Crystalina are now unable to be used in rinse off products such as Bath Bombs, Soaps, Body Butters etc. due to the Microbead Ban from January 2018. They are fine to use to use in Leave On products, but the ban has come into force for rinse off products.
Bio-glitter® can be widely used in most cosmetic products and add a decadent sparkle to bath bombs and bath salts. They are made on a cellulose base which is completely biodegradable and as such have huge environmental advantage over standard cosmetic grade poly-glitters.
- A little goes a long way, so use sparingly.
To view the colours and application chart, click here