Thursday, September 17, 2009

Dear Laundry Soap Manufacturer

How come your "perfume free, dye free" detergent turned red when I poured it into my washing machine filled with water and bleach?

Nope.  I had no clothes in the washer at the time.

Explain, please.


Bob said...

Interesting question. I found this explanation. So I'm guessing this was "Liquid Tide" (a.k.a., "Tide Free") that you were using.

Google also turned up this description in Proctor and Gamble's patent of how Tide Liquid's "brightening agent" works (which isn't directly related to your question of what makes the water turn red, but it's interesting nonetheless).

Optical brightener deposited onto the fabric results in a perceived enhancement of overall whiteness owing to their inherent properties of generally absorbing ultraviolet wavelengths of incident light (and hence are colorless to the human eye from an absorptive contribution) and emitting longer wavelength light via a fluorescence mechanism. This fluorescence emission, typically at lower energies and hence at visible bluish to reddish wavelengths, effectively contributes a bluish to reddish colored tint to the incident light that is reflected from the fabric surface under illumination, which is then perceived by the human eye and hence the fabric surface is perceptually seen as being a "whiter" white. Since cotton and other fabrics tend to have a slightly yellow or grayish cast, particularly with age and wear of their respective fibers, the use of optical brighteners that deposit onto their surfaces during the wash process can significantly mask this discoloration and provide a pleasing overall white appearance to such treated fabrics.

To put it plain, Tide Liquid masks the yellowing of fabric by leaving behind a deposit that fluoresces in the red and blue spectrum. Check it out by shining a black light directly on a spot of the detergent. Tide glows in the dark!

Anonymous said...

in simple terms......EVERY unscented liquid I have used does the same thing when i have bleach involved. Has never stained my clothes... "yet"

Thumper said..., the truth is, your washer is possessed by the devil, and every time you use it a small piece of your soul dies. I wouldn't lie to you. Really.

Andy said...

Roses, I'm with Thumper on this one. Thumper would not lie to you. Really.

Bob said...

Okay, I know when to admit I was wrong. It really is demon possession.

Green-Eyed Momster said...

Seriously? I've never heard of that! Yikes!


Roses said...

Thumper: You've never led me wrong.

Andy and Bob: In any case, why take chances, right?

Harvey said...

Good to hear I'm not alone. I thought it was just me having a washerful of mysterious contaminants.