Urea lotion simple

# Urea, Xylitol, Farnesol Lotion (Simple)

This is 'simplified' version of the Urea, Xylitol, Farnesol lotion that I made based on studies regarding biofilm disruption and ezcema.

I have removed:

- Double buffer
- Feel and effect factors
- Thickener
- Dimethicone
- Multiple humectants

It is going to feel basic. It will not have a nice glide, has longer rub-in and may have some soaping. However, it is perfectly useable and will have similar (if not  the same) skin results.

Since there are less stability factors in this version, the airless pump containers are highly recommended. Unfortunately there are no other ways of dispensing the product without exposing it to air and contamination. Check at the end of this document for more information about airless pumps.

## FORMULA

| Ingredient | Percentage |
|------------|------------|
| Distilled or deionized water | remaining% |
| Xylitol | 5.00% |
| Xanthan | 0.30% |
| Glycerin | 5.00% |
| Petrolatum | 10.00% |
| Mineral oil | 5.00% |
| Emulsifying wax NF | 4.00% |
| Citric acid monohydrate | 0.23% |
| Farnesol | 0.20% |
| Urea | 8.00% |
| Sodium citrate | 1.10% |
| Germaben II | 1% |

## Ingredient Notes:

- ALL INGREDIENTS ARE NECESSARY
- Citric acid monohydrate is the typical form of citric acid available to consumers, if your source doesn't specify, assume monohydrate
- Germaben II is the preservative tested to work with this formula. Using other preservatives must be done with the formulation in mind according to the preservative's compatability. Possible alternates have not been tested but could include euxyl k 940, Phenonip, and Geogard ECT aka Preservative Eco.
- For a calculator to compute weights and water percentage head to http://lotioncalculator.com
- Despite 'general knowledge' mineral oil and petrolatum are NOT comedogenic
- If your urea comes as prills, you will need to crush or grind the prills using a coffee grinder or mortal and pestle and sift it to remove any chunks which can be reground
- Zero-water filters contain mixed-bed deionizing resin which will provide you with a way to turn tap water into deionized water on demand
- This formulation uses ingredients that are generally accessible by consumers in the USA. Other countries may not be able to source some ingredients, and alterations could have an effect on the end result

## EQUIPMENT

- Stick blender
- Scales:
  - Accurate to a gram or lower and capable of multiple kilograms (normal kitchen scale)
  - Accurate to a tenth of a gram or lower and capable of up to a kilogram (milligram scale)
- Large heavy bottom pot with medium high walls or double boiler
- Instant read thermometer
- Measuring spoons
- Small whisk or stick
- Airless pump product containers 100mL to 150mL in size (assume 100g product is equal to 100mL)
- Glassware:
  - 1x very large (2L+) glass bowl with spout for final mix
  - 2x large (1L or 2 cups) glass measuring cups
  - 4x medium containers for weighing and mixing ingredients
  - 4x small containers for weighing ingredients
- Spray bottle filled with 70% to 92% isopropyl alcohol
- pH meter
- Timer
- Calculator

## PROCESS

The first thing that needs to be done is washing the equipment that will be in contact with the product and setting up the production area. To clean these items you want to wash with a detergent, rinse thoroughly with tap water, then spray heavily using the spray bottle of isopropyl (warning: it is highly flammable, do not do this near a gas stove), then place on a rack to dry.

Have a print out or a written copy of the formula on a clipboard with a pen handy.

Have all ingredients out and ready to access. Have paper towels and dispensing tools handy and easily grabbable. Have a calculator nearby.

Place your scales in a flat, out of the way area. Weigh the large (2L+) glass bowl and write the weight with a sharpie on the side of the bowl – this will easily come off with isopropyl, don't worry.

Place a large measuring cup on the scale and tare (zero) it – after adding each ingredient you are going to tare the scale again so you don't have to add the numbers each time. Add petrolatum (you can scrape it on the side if you like, it will turn into liquid and flow down when it heats up) until weight is reached and tare the scale (remember to do this every ingredient addition), then add mineral oil, then emulsifier.

Fill the heavy bottomed pan about ¼ full with tap water and set it on med heat, when the water starts bubbling turn it down until it stops. Place the measuring cup with the oils in it in the water and put a thermometer in it.

Put the other large measuring cup on the scale and tare it. Add about 3/4 of the water needed for the entire product in the vessel (remember to use purified or deionized water). Place the vessel in the water bath.

Weigh and add xylitol, farnesol, citric acid and sodium citrate to the water.

In separate vessels, weigh out the urea and the preservative and set them both aside.

### Xanthan Gum

Xanthan gum is notorius for clumping unless you mix it properly. Always mix it into the glycerin before adding it to the rest of the ingredients.

Put a medium size container on the scale and add the glycerin.

Weigh the xanthan gum using a small container.

Now very gradually add bits of xanthan to the glycerin while sitrring until all the xanthan is incorporated and there are no clumps.

Add the xanthan and glycerin to the rest of the water ingredients and mix.

### Temperature Control

Monitor the temp of the oil vessel and the water vessel. You will need to lift the thermometer so that it is not touching the vessel to get a proper reading of the liquid. When they reach 70C (160F) set a timer for 10 minutes. Make sure the temp does not drop below 70C (160F) during this time. You will need to monitor the water level in the pot and add water to it if needed. It is helpful to have an electric tea kettle running on the side so you can add already boiling water and not have to cool down the whole pot every time water is added.

**Why 70C for 10 minutes?**

Technically, all we need to do to get a good emulsion is bring the water and oil phases to the same temperature and mix them, so why hold at 70C? Well, boiling water is a good way to kill the microbes in it but there is nothing magical about 100C that kills microbes – if we get it up to 70C and leave it there for a while it will be almost as effective as boiling it, and it won't cause nearly as much harm to the ingredients.

### pH Check

Check the pH of the water ingredients by putting the pH meter into the vessel. Let the reading stabilize. If it is over 6, add a tiny pinch of citric acid. If it is below 5, add a small pinch of sodium citrate. Mix and check again.

### Final Mix

When the timer goes off, pour the water vessel contents into the large bowl, place the blender in it and turn it on low, then dump the oils in and let it run, blending everything together. DO NOT LIFT UP AND LOWER THE BLENDER WHILE MIXING, this will incorporate air into the product. You do not want to let the mixer blade to ever come into contact with air while spinning.

When the temp of the product goes below 60C (140F), add the urea and preservative and continue to mix.

Tare the scale and put the vessel on it and add water until it reaches product weight.

```
SCALE_WEIGHT - MARKED_WEIGHT = X
DESIRED_END_WEIGHT - X = AMOUNT_WATER_TO_ADD
```

Take it off the scale and mix it.

If it starts getting thick it is time to dispense. If it remains liquid then as long as you have mixed for at least two minutes you can dispense.

Pour the product into the containers. If you are using airless pumps, you will want to fill as much to the top as possible while leaving room for the pump to fit. You don't want to spill over so do one and put the pump on to see how much to leave at the top, then fill the rest of the containers until you run out of product and then cap them. About 100g of product is about 100mL of volume, and plan to make about ½ of a container extra for the batch.

### Quality Control

In a week check your product with the pH meter by dispensing some in a vessel and mixing it up to 50% with warm deionized water. If it is below 4.5 or above 6.5, something is wrong and you need to figure out what before you keep using that batch.

Check again in another few days and then every week for a few weeks and then every month until that batch is done. If you are consistently making stable batches you can skip the regular post-production pH checks but you still want to check each batch in its mid-lifetime at least once to make sure something hasn't gone horribly wrong.

It isn't guaranteed that a problem will make the pH change a lot, but if the pH does change a lot then it is guaranteed that there is a problem.

### Airless Pumps

Normal lotion and soap pumps work by pushing the product out of a nozzle by creating a vacuum. You can compare this to sucking liquid through a straw. If you try to suck liquid with a straw out of a perfectly sealed container, the container will collapse, so there must be an air intake to replace the product when it is removed. This is why normal pumps are not suitable for products that have to stay sealed from external elements.

An airless pump uses a piston at the bottom of the container so that air doesn't need to ingress. Imagine a tube with an endcap at the bottom and a dispenser on top. When the pump is pressed and product is dispensed, the endcap at the bottom moves up, so there is never any empty space in the container. The piston effectively makes the container smaller so that the product always takes up exactly enough room inside of it to not leave any air.

Empty airless pumps are generally available wherever you source product containers. However they are sometimes limited in size. Try to find 150mL containers if you can or 100mL if you cannot.

If in the USA you can obtain good quality ones from a distributor of pharmacy equipment called PharmaPump-USA. An order for 25 154mL bottles and 25 pumps aka 'engines' (bottles and pumps are separate items) with taxes and warehouse fees cost around $70 or $2.80 per container. They are not supposed to be reused, but there is nothing preventing a person from popping the engine off, pushing the piston down, cleaning the bottle and refilling it.