STPP revisited

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DADoES

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I recently bought a batch of STPP. I know it has been discussed ad nauseum, but I'd appreciate clarification on a few points.

1. The purpose of it (mainly) is water softening/conditioning?

2. How does one determine the appropriate dosage for local conditions? Dose to achieve "slippery" water without detergent? Or is that not necessarily enough in proportion to the detergent dose? I've been using a 1 oz. scoop of STPP with about 1/2 the recommended dose of detergent (Tide HE powder, Wisk HE 2X liquid, Fab powder).

3. I assume it's compatible with oxybooster and LCB?

4. My water is fairly hard at ~11 grains. Could a smidgeon be used as a rinse conditioner? The Calypso does 4 or 5 to as many as 7 rinses (some shower/spray, some fill/nutated), the final rinse dispenses softener. Perhaps 1 teaspoon STPP in one of the interim nutated rinses?
 
Phosphates not only soften "hard" water, but work in many other ways to make for great laundry. Things such as keeping soils in suspension and away from laundry, and also "charging" wash water so it cleans better.

In general, one adds enough phosphates to soften water so it feels slippery, which is probably the most easy test for domestic users. Normally one can decrease detergent use by 1/3 to 1/2 in ratio of STPP, depending upon factors such as soil and stain levels, and water hardness.

If one has hard water, then yes, water softener can be added to the rinse water as well, just not too much as too soft water is just as bad for rinsing as too hard. When soap was the queen of wash day, women doing laundry in hard water areas, would soften rinse water, if they couldn't get rain water, as hard water would cause soap scum on their laundry.

Yes, STPP is fine to use with either oxygen or LCB. Just remember many oxi-boosters contain washing soda, surfactants and such, therefore you may need to reduce your detergent level even more if adding a healthy dose of oxy-booster product.
 
I'd say it depends on your water. Here in ATL, I use 2-3 tablespoons in a standard toploader to get slippery water, maybe 1 teaspoon in my Miele.

For the Calypso, I'd dose it like a frontloader. I know TX has pretty hard water. Can you start the washer with STPP and check under the recirc stream, adjust, add clothes, then detergent?
 
Hi Glenn

Phosphates principal function is to bind up calcium , magnesium and other minerals in hard water. Detergents(read surfactants) Surfactants are really surface active agents that make water wetter by reducing surface tension of water.
If only surfactants are introduced into hard water then all their detergency goes into binding up with the minerals in the water and not in reducing surface tension to clean.
Water is the solvent that does most of the cleaning so the deeper it penetrates the clothes the cleaner they will be. Surfactans allow the water to penetrate under and around and between the dirt=(grease or dust) and the fabric thus releasing the dirt from the clothing. This process is called "roll up". Because the water & surfactant actually roll the dirt up and off the fibers.
Different surfactants work in different ways with different fibers. That all depends on wether the fibers are plant, animal or synthetic derivatives.
Surfactants are classed by their charge, anionic (negative) cationic (positive) non ionic no charge. If I remember this right the non ionics are used for fabric softeners.

All your dirt should be out of the clothes by rinse time so adding phosphate then will have no cleaning effect but adding a non ionic will add to the cleaning and softening of your undies. Non ionics do clean certain dirts as well as lubricate natural fibers, don't use them with any synthetics though.

In the 60's formulations contained all kinds of mixes with phosphates, even calcium carbonate was used to reduce the amount of phosphates needed as CC was cheaper than STPP.

Jet
 
STPP and Soft Water

Hi. I have been wanting to try STPP. My home has a water softener and I was wondering if this would be overkill, or would the STPP still aid in cleaning. WOuld I just have to use a smaller amount?

Thanks for your help.

Ray
 
Slippery water

Gosh, I'm almost embarresed to admit this, but my knowledge of detergents (what they are and how they work) is basically limited to the one thing I "know"...that when adding detergent, the water should be slippery. That's how you tell if you have enough detergent. So I often stick my hand in the load to see if it is slippery. If it isn't enough, I add more detergent. So if you acheive slippery water with detergent, does that mean you don't need STTP? If you still do need it, then how do you tell if you have added enough STTP if your water is already slippery?
I have used it before. When I first moved to sacramento 13 years ago, a friend was using it for his whites. I've tried it and don't seem to remember any amazing results. The last time I bought a box (about 6 months ago) at the 98 cent store, it made my clothes smell like it. And I had washed a load of darks on hot water and a tshirt I had came out a different color!! But when it dried, it went back to it's normal color. What was that all about?!
As for buying it, you can get it at Home Depot I believe, and usually any old hardware store will have it. But mostly I see it at the 98 cent store for a large box.
Oh, is Borax the same thing? I usually throw in a 1/2 cup of borax with my laundry. I don't know why I do...the box said it cleans better with the use of it..so like any ignorant consumer, I believe the box and use it! LOL! Same goes for Clorox 2!!
Thanks everyone. -Laurent
 
Nope, you cannot get it at Home Depot or any hardward store. That product is TSP, usually used for pressure washing stains off of concrete. Laundress will know, but it is not suitable for laundry...
 
The Master Weighs In

1. The purpose of it (mainly) is water softening/conditioning?

Answer: It would depend on your water quality. If your water is hard, then STPP would be of value for softening the water. However, STPP also aids in cleaning regardless of water quality. This is because much dirt is like hard water minerals, and STPP helps to break it away from the fabric and hold it in suspension so that it can be rinsed away.

2. How does one determine the appropriate dosage for local conditions? Dose to achieve "slippery" water without detergent? Or is that not necessarily enough in proportion to the detergent dose? I've been using a 1 oz. scoop of STPP with about 1/2 the recommended dose of detergent (Tide HE powder, Wisk HE 2X liquid, Fab powder).

Answer: Whatever works. By trial and error, depending on your water quality, your washer, and your laundry type, you'll find what works best. I just premix a powdered detergent with some STPP, to about a 67% detergent 33% STPP ratio by weight. I do about 20 lbs of detergent at a time this way, and I use a little 1 cu ft roll-on-the-floor plastic cement mixer barrel for this. Quick and easy. This ratio seems to work fine for all types of laundry in my Neptune 7500 and also in my Miele 1918. For detergent, I use Sears Ultra Plus HE. I generally use about 2 oz of the resulting mix per load - more if there's a lot of dirt/oil in the laundry (like for soiled work clothes). For use with liquid, 1 oz of STPP per load sounds about right, although I generally only use liquid for items like bath towels, with no STPP added.

3. I assume it's compatible with oxybooster and LCB?

Yes.

4. My water is fairly hard at ~11 grains. Could a smidgeon be used as a rinse conditioner? The Calypso does 4 or 5 to as many as 7 rinses (some shower/spray, some fill/nutated), the final rinse dispenses softener. Perhaps 1 teaspoon STPP in one of the interim nutated rinses?

My water is relatively soft (3 to 5 grains) and so I haven't detected any difference in final laundry quality by rinsing with/without STPP. If you do use it, I would dissolve it in a small amount of cold water prior to adding to the rinse dispenser. Most rinses are fairly short and you want to make sure the STPP is completely dissolved by the time it drains. I would not, however, make a large batch of dissolved STPP to sit on the shelf, because it will be unstable and deteriorate into much less desirable TSP over time.
 
Addendum

The much discussed "slippery" feel is a result of the alkalinity of the wash water. Washing soda (sodium carbonate) is the usual main ingredient in most detergent powders, and it is actually more alkaline than STPP, so it alone will result in a slippery feel. Many liquids, in my experience, in the amounts needed to avoid oversudsing, don't impart a very slippery feel to the water. They generally use the less alkaline sodium citrate as the water softener.

Borax is a mild water softener and has some ability to suspend soil and keep it suspended to be rinsed away. But it's nowhere near as effective as STPP for these things. It does a good job of deodorizing, however.

TSP is a breakdown product of STPP. Technically it's called the "orthophosphate" while STPP is the "complex phosphate" or "polyphosphate". TSP could be used in laundry but it will cause minerals to precipitate just as washing soda does. This precipitate looks like white lint and will tend to cling to fabrics as it gets caught by the weave. TSP is best used to clean and degrease hard surfaces, where a precipitate that can be easily wiped or rinsed away will not be as much of an issue. It's normally used to clean old paint to etch it and give it a "tooth" for new paint to stick to - but it must be thoroughly rinsed off as any residual alkalinity will interfere with most paints (a mild vinegar rinse may help neutralize the etched paint surface prior to repainting).
 
Where to buy...

Chemistry Store is good. I've seen people buy it from Candlelight as well.

I bought a large amount some years ago in 50 lb sacks from a local chemical warehouse in Oakland. If you're in Sacramento, you should be able to find a warehouse that will sell to you direct, since STPP is perfectly legal to use in home laundry in California.
 
OK, so STPP is basically putting the phosphates back into the laundry that detergent manufacturers had to stop including back in the 70's or 80's? And it's perfectly legal? Then why not just have the phosphates included with the detergents again?

And yeah, I was lucky to maintain a C average in chemistry class.
 
The current arrangement is better IMO. Phosphates aren't needed for every washload, and the amount of it released into our environment has been greatly reduced. It and nitrogen (from farming runoff) were the two biggest causes of water pollution in lakes and rivers in the U.S.

Most dishwasher detergents still contain phosphates, because nothing else has been found to effectively replace it.
 
I will say that when using soap (grated Fels Naptha bars) in the washer, using some STPP in the first rinse does help suspend soap out of the clothes and prevent soap scum (tattletail gray).
 
Running a small load of sheets this evening, I let the machine fill before adding 1/2 oz. STPP. The water immediately got "slippery." Is that really enough to have the full effect of "charging" the water and helping to hold soil in suspension? I added another tsp for good measure, LOL. Then 2 oz. of Fab powder.
 
Cheaper in person!

I've been buying it for years at my local cleaning product company/janitorial supply, 50lb bag for $44. At a teaspoon or so per load, it lasts and lasts. I recently sent some to a friend in Cleveland and he was amazed at the results with standard, non-phosphated detergent. The supply house I buy it from also makes their own STPP fortified detergent that is incredible, I've almost been using that exclusively now for everyday washing.
 
You really don't need to use lots of STPP, just enough to get the job done. Remember too soft water for washing is just as bad as too hard. If water is too soft you will have to rinse and rinse to get detergent out.

On this same principle, if one is already using softened water form a whole house system, then adding STPP is not required. Indeed many persons find using even small amounts of their regular detergent with mechanically softened water causes problems. Some water softener makers have their own laundry product lines, designed to work with softened water.

Really only use STPP for whites and perhaps light coloured laundry, and even then only with certian detergents. Find many European detergents give excellent results on their own without any additives, including STPP. However just to stretch the stuff out, will cut detergent dosage and add some STPP.

STPP really does shine when one is using soap such as Lux flakes or STPP for laundry.
 

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