The Science Of Laundry

Could there be a less enticing title for a blog post? Science and laundry? I know this is a tough sell, but stick with me. I hope to make it worth your while.

I have been navigating my way through a very specific laundry problem since January, using science to diagnose the cause of the problem, testing products that scientifically promised to remedy the issue, and happily discovering a solution that is working and making my niche laundry problem a thing of the past. Today I want to share it with you in case you find yourself in a similar situation.

Let’s start with the problem.

I bought white, 100% cotton sheets for my bed in January. I bought two sets because I always buy two sets of sheets for every bed in our house so that a set of clean sheets is ready to immediately put back on the bed when we change the sheets. And, if you’re curious, I change my sheets weekly, on Sunday, and it is one of the best parts of my week. There is nothing better than heading into a new week with clean sheets.

New white cotton sheets, changed weekly, and washed weekly should be simple enough to keep clean, right? Wrong.

Four weeks in, as I was folding our relatively new, very frequently washed, white cotton pillow cases, I noticed the center of the pillow cases (where we rest our head) was dingy and taking on a yellowish hue. If these sheets had been years old, or if they were rarely washed, I might understand the discoloration. But new sheets that are washed frequently should not begin to look yellow with weekly washing after only four weeks.

Pause for a few background details.

I do not use fabric softener for many reasons, but primarily because all it does is coat the fabric and make it more difficult to clean. It also renders towels less absorbent.

I also want to let you know that about a year ago I switched from commercial laundry detergent to a concentrated spray laundry detergent from Clean Mama. I love it. It works. One thing I have learned about laundry and laundry soap is that more is not better. Imagine if you put a ton of shampoo in your hair but didn’t rinse it all out. Your hair would look dirty despite having a lot of soap in it.

So it goes with laundry detergent. More is not better. Most of us could throw our clothes into the washer without a drop of added soap and have the water suds up due to all of the residual soap hanging out in the fibers of our clothes. Do with that information what you will. It’s not the point of this post, but it is an important detail to mention that the cause of my dingy pillowcases was not a surplus of detergent coating the fibers, nor was it a build up of fabric softener.

Anywho, back to my pillowcases.

I dove deep and did a lot of research on laundry and how soap works and why white cotton fabric would begin to show signs of yellowing so quickly. I got into the chemical attributes of soap, how fibers hold dirt, and discovered the root of my issue is…minerals!

Minerals occur naturally in our tap water, and if you have a high number of minerals in your water, your water is referred to as “hard.” Unless you have a water softening system in your house (which filters out minerals), you have minerals in your water. The degree may vary based on where you live, but we all have a certain amount of minerals in our water.

Minerals are why the flow on your shower head slows with time, why you get a white chalky build up on your shower walls or shower caddy, and, as it turns out, why my pillowcases were dingy. Minerals present a problem when it comes to laundry because minerals present a problem for soap.

Do you know how soap works?

Soap works by chemically attracting and bonding to particles like oil, dirt, and sweat. When the soap is rinsed away, it takes the dirty particles with it, leaving the fabric clean and dirt-free. In a perfect, mineral-free world, this process is very straightforward. However, throw some minerals into the mix, and guess what happens? The soap attaches to the minerals in the water instead of attaching to the dirt. The soap never makes its way to the dirt in your clothes, so the dirt stays put. Minerals hijack the soap, taking up all their chemical bandwidth, leaving very little space for them to cling to dirt and carry it away.

This is happening all the time, but we don’t notice it as quickly in our normal clothes because they are not white. But in my new white sheets, I noticed it almost immediately. With the minerals in my water dominating the cleaning power of my soap, the pillowcases were not getting clean, and the oils deposited from our hair and face were building up instead of being washed away.

At this point, most people would add bleach, thinking the bleach is cleaning the pillowcases. But bleach does not remove dirt. Bleach removes pigment. Bleach is also is very caustic and damages the fibers, causing them to break down more quickly over time. Oddly enough, frequent bleaching also creates a yellowing on white fabrics (probably because at some point all of that dirt begins to show!).

The problem? Minerals.

The solution? Science!

In order for the soap to make its way to the dirt without getting hijacked by minerals, we need to introduce an ingredient into the laundry water that will bind to the minerals, allowing the soap to fully bind to the dirt and do its job. Bonus points if this ingredient will add to the overall effectiveness of laundry soap.

Great news! There are two ingredients that will do this for you, and you can use them independently or together in conjunction with your laundry soap of choice. The ingredients are Sodium Carbonate and Sodium Borate! Let me introduce you to their more familiar retail names.

Sodium Carbonate is sold as Super Washing Soda (Washing Soda is not the same as baking soda, but is manufactured by Arm and Hammer, who also makes baking soda. Don’t get confused.).

Sodium Borate is sold as Borax, and you might remember this ingredient from your grandmother’s laundry room.

I began adding Super Washing Soda and Borax to my laundry (half of a cup of each directly in with the clothes), and to my delight, the dinginess disappeared and my white sheets stayed white! Excited by the results, I began to test these products on our towels, which are also white and about a year old. It worked equally well. Our towels are now sparkling white, and have a texture that feels clean and ready to absorb water instead of coated and dingy.

I know this is a lot of laundry information and a lot of science to boot, but here is the summary statement. To keep your white sheets and towels looking white, add 1/2 cup of Borax or 1/2 cup Super Washing Soda (or, even better, both!) to your laundry along with your soap.

For added effectiveness, make sure you are not overloading your washing machine, wash your white sheets and towels with hot water, and extend the wash cycle time for maximum agitation which gives the soap lots of time and opportunity to get all the dirt out.

Important note: Regardless of the kind of washing machine you have (front loader or top loader) Borax and Super Washing Soda go directly in the drum of your washing machine with the clothes. Both are great for whites, but are also safe to use with colors. They are not meant to replace laundry soap, so you will still need to use a detergent.

While we are talking about laundry, I want to quickly share a few other laundry specifics that I use in my home.

Like I mentioned, I have been using the Clean Mama Super Concentrated Laundry Detergent Spray. This product is sprayed directly into the washing machine with the clothes.

I also use the Clean Mama Oxygen Whitener , which is an enzymatic cleaner and also goes directly in with the clothes.

Instead of fabric softener (which I never use), I add 1/4 cup of white vinegar to the fabric softener cup in my washing machine. No, my laundry does not smell like vinegar, and, you guessed it, yes is a natural fabric softener. I know it sounds crazy, but it’s true.

I store my Super Washing Soda and my Borax in the 3.3 liter size of these acrylic containers. They are the perfect size to hold an entire box and a measuring scoop with ease.

In the dryer, I never use dryer sheets, but I do use wool dryer balls. They help soften fabric as well and keep static electricity at bay.

If you have been a frequent user of too much detergent and fabric softener, chances are your towels and sheets have quite a buildup of product and dirt. I would suggest stripping these items to create a somewhat clean slate before beginning the new regimen. How do you strip laundry? This blog post explains the process. I stripped my clean towels, and I can attest that the water was exceptionally dingy, confirming that my clean towels were not in fact very clean.

If you have any follow up questions or want to hear more about my laundry journey, I am all ears and would love nothing more than to talk soap and science!

If you are curious about how I manage laundry in our home, check out this podcast episode!

Thank you for hanging with me as I share my laundry and science adventure!

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