Colourant types? Colourants are used in everything from clothing to toys and cosmetics to food. There are two main types:
Natural – They come from natural sources such as plants and minerals and, in some cases, insects.
Artificial – They are chemically made colourants. Most of the ones we use fall into this category.
In this post we will talk about artificial colourants.
The difference between dyes, pigments and lakes? A dye is a chemical powder that is water soluble. When it is dissolved in water it produces colour. Dyes are highly concentrated. They will colour your water. Below is a perfect example of how you cannot really tell this was blue until water was added to it. Initially it looked purple.
An Aluminium Lake is a dye mixed with a metallic salt or some other compound in order to make it insoluble – it is a dye that has been turned into a pigment. Lakes are not water-soluble OR oil soluble, they are oil dispersible. This means that the oils will disperse the lake colourant through the water but it won’t actually dissolve it. Lakes are produced in different concentrations. Low Dye (generally 15-17% pure dye) and High Dye (generally 36-42% pure dye). Lakes are a lot less concentrated than a true dye. This is why when you look at lakes, the powder looks nice and bright, like the colour you are expecting but when you look at a dye it looks very unlike the colour you are expecting UNTILL you add it to water.
A pigment is water insoluble and oil insoluble. They do not dissolve but they will disperse. An example of pigments are Oxides and Ultramarines.
I could be wrong but I believe Lakes only come in small variety colours. Blue 1, Yellow 5, Yellow 6 (orange), Red 40 are the ones you will usually see for Bath Bombs. There are some other reds available and Blue 2, but it isn't approved for cosmetic use in some places.
There is a Violet no 2 in a dye, which is beautiful, but it’s expensive. There is Manganese Violet, which is a pigment. It’s quite bright and pretty but as it’s a pigment, it’s water insoluble so you need to disperse it.
You can mix lilacs or purples either Red 33 or Red 28 (or both) with Blue 1. Greens can be done in the same manner using blue and yellow.
Using food colour gels in bath products If you are making your bath bombs and products for personal use it is fine. If you are making products to sale then it is required that you use the proper colourants.
What are “Bath Bomb Colourants”? They are not really a separate category of colours - they are Lakes or Dyes. They work well in bath bombs as they colour the water BUT if you use Lakes then you will need to use Polysorbate as they are not water soluble as mentione earlier.
Does Food Colouring stain the bath? It depends on how much you use. BUT Dyes can also stain – if you don’t use them correctly. If you placed a little bit of Blue no 1 onto your hand and added water your hand would end up stained for a little bit of time.
Red 28 dye is notorious for staining.
Now, don’t let this turn you off using dyes. Dyes are our go to colourant in bath products. We use a mini scoop of dye in a batch of bath bombs to make a nice colour. We use more when making colour embeds. If you grab a bath bomb and squish it while it’s fizzing away, then you could end up with coloured hands.
As for staining the bath tub, we haven’t had any instances of this and we use dyes in our bath bombs. We have been known to put our bath bombs on the edge of the bath and leave them overnight for use the next day.
Dyes might stain your bath tub is if the enamel was badly damaged or scratched.
As Lakes are made with dyes you may find that they will stain if overused. Lakes are generally a lot less concentrated than a true dye so people probably believe ‘lakes don’t stain but dyes do’ when really it’s just that lakes aren’t as powerful.
Dyes/Lakes put a ring around my bath. If you are getting stains around the water edge and it is a little oily this could be the oils and butters in your recipe. If you have used Mica in your bath products you may have seen this happen, that’s why people use Polysorbate to disperse the oils so they don't stick to the edge.
Basically, if you are making bath bombs with oils, go easy on the Lake or Dye. If you want really vivid colour, make sure you include something like SLS or Polysorbate.
Is it a Dye or a Lake - they all look like powders? Look at the INCI for the product you want to buy. If you are purchasing Brilliant Blue and it is a Dye it will say “FD&C Blue No. 1”. If it says “FD&C Blue No. 1 Al Lake” then you are buying a LAKE. If it says “C.I. 42090” then you are buying a DYE. If it says “C.I. 42090:2” then you are buying a LAKE.
The colon with a number following the colour index number means you are looking at a Lake because there has been a chemical change indicated by the colon number.
If you buy a powder and aren’t sure if it’s a dye or a lake, throw it in water. The dye will instantly give you a very concentrated colour and dissolve but the Lake will give a little colour and the powder may be floating on the top or sink to the bottom.
At Riverlea we use Dyes and we call the Fizz Colours.
Tips for using Lakes and Dyes Dye powders are water soluble so they won’t “bloom” colour until water or some kind of water based product is added to them. When it comes to bath bombs this means if you aren’t using water or something water based in your bath bomb mix, your bath bombs aren’t going to look brightly coloured until they hit the water. Do not think that they are not strong so you add more dye powder to your mix if you only using oils to bind. We recommend you add a tiny bit of water to the dye first. If you spritz the mix with water you will see instant colour. If you do use some water or a water-based ingredient to bind your bath bomb mix, you will get a vibrant looking bath bomb that also colours the bath well.
If you use Lakes, they will show good colour in a bomb mix regardless of what your binding ingredient. Usually you will get a bright coloured bath bomb when using Lake powder which will then colour the water nicely. You need more powder than you would a Dye and the lake won’t dissolve in the water, You will also never get as vibrant a bath colour with a lake as you would a dye. Unless you use a lot of that powder.
Working with the dye powders remember LESS IS MORE. They are POTENT.