Creating a cosmetic lab - Heating and Cooling equipment

Here’s the next article in our series about starting a cosmetic lab.  Here is the basic equipment you’ll need.

• Containers
• Weighing equipment
• Mixers
• Heating & Cooling equipment
• Lab supplies
• Testing equipment

We have already covered the first three topics. In this post we will cover the topic of Heating and Cooling equipment.

Why you need lab heating / cooling equipment

There are a few reasons why you need a way to control the temperature of your prototypes. These include…

• Melting water-insoluble solid ingredients
• Creating emulsions
• Reducing air entrapment
• Reducing viscosity
• Speeding up production

Since many cosmetic ingredients are solids that aren’t soluble in water and most finished products are liquids or creams, when formulating you need a way to melt them.  This is particularly true when creating emulsions.  Creams & liquids are typically emulsions and these need to be heated above the melting point of some of their ingredients, then mixed at a high temperature to ensure you get a small particles size when finished.  It takes energy to make an emulsion.

From a production standpoint there are good reasons to have lab heating and cooling abilities. If you don’t have the proper mixing equipment it is likely that you’ll trap air in your batch. When you make products at a higher temperature the air is less likely to get trapped.  Also, if you are producing a product that is very thick often heating will reduce the viscosity making it easier to incorporate other ingredients.  Finally, your production people like batches to be a little warmer than room temperature because this makes it easier to pump and fill the bulk formula.

Lab Temperature Control Systems

To set up a proper cosmetic lab you’ll need a way to easily heat and cool your batch. The best option for heating your batches is a hot plate.  The best option for cooling your batches is a water bath.  Additionally, you’ll need a thermometer to be able to measure the temperature inside your batch.

Cosmetic lab hotplates

Hotplates have a number of features that are variable such as their top temperature, the heating surface, and temperature controls. For a cosmetic lab it is useful to have 

• A ceramic coated plate for chemical resistance which is also easy to clean
• A temperature range of at least 200C. Since most formulas don’t require you to go higher than 100C, this is more than adequate.
• Stirring capacity of at least 3L. Depending on the size of your batches you may need a larger hot plate than this.
• Temperature control - so you can modify the speed at which your batch heats.
• Lightweight - Since you will often be moving your hot plate it is useful to be lightweight

One options suggested by one of the chemists in our forum is the Scilogex MS-H280.

I personally don’t like to heat beakers or other containers directly on the heating plate.  For this reason I like to use a metal bowl filled with water. That way you ensure that the batch never goes over 100C.  Also, when you are ready to cool down the batch you can simply add cold water to do that.

Cooling water bath

As I said, I don’t like to heat directly on the hot plate but rather use a bath full of water to surround the beaker and heat up the water around it. This gives you much better temperature control and allows you to cool the batch without relying on only air.  To do this you need a container that has a wide opening and is also shorter than your mixing container. 

A stainless steel pan like this would work well.

You fill the container with water, place it on the hotplate then put your beaker container in it so the water surrounds it.  Only fill it as high with water so it covers about an inch of the beaker. This controls the heat well enough and you don’t have to worry about it boiling over.  When cooling, you can add cold water and ice.  You can also change the water if it gets too hot again.  Just remember to remove it from the hot plate.

Lab water bath

Speaking of water baths, these are useful for storing samples that you are trying to cool or even heat up. A water bath like this one is helpful in a cosmetic formulation lab.

The heating and cooling equipment in your lab is crucial to have for setting up a cosmetic lab. Fortunately, it will be one of the less expensive things that you have to get.