Newsgroups: sci.chem
From: B.Hamilton@irl.cri.nz (Bruce Hamilton)
Subject: Re: WD 40 Ingredients
Date: Thu, 12 Jun 1997 15:41:41 +12

In article <5n9c5h$5vt@freenet-news.carleton.ca>
ca805@FreeNet.Carleton.CA (Everett J. Harriman) writes:
...
>Does anyone know the composition of the product, "WD 40"?  I'm
>especially interested in identifying the ingredient used to give
>the penetrating property to WD 40.

The WD stands for Water Displacing. I haven't analysed it,
( not commonly sold here ) but somebody ( Professor Toraki? )
squirted some down a GC/MS and confirmed the solvent was
boiling around 150-200C and only contained a minor % of
aromatics, which means it is either a narrow boiling range
kerosine fraction, or a special narrow boiling range solvent
like low aromatics white spirits.

I've analysed a similar product, and it was around 80%
kerosine, 10% acidless tallow oil, and 10% lubricating
oil light base gade - with some additional antioxidants
added to improve durability. When the composition of
WD-40 last came up in sci.chem, I wasn't sure if it was a
water displacing solvent only, but subsequently there
has been a long discussion about the film left behind in
some rec.* groups - which is why it should not be used as
a lubricant, the film is only a temporary corrosion protective
layer.

That would make WD-40 like the formulation above.
The kerosine is the solvent, the tallow oil and lubricating
base grade provide the means for the fluid to displace
water from surfaces and, when the kerosine has evaporated,
leave a thin, protective film on the surface that provides
temporary corrision protection. It is possible that it may
have some solid lubricant in it ( PTFE,Graphite,MoS2 ),
but I suspect there would not be enough to provide any
useful lubrication - and thus should not be used to wash
"proper lubricants" off bearing surfaces, chains etc..

Note that the light lubricant base grade is just the vacuum
distilled, high boiling, hydrocarbon fraction used in light
lubricants, but has minimal lubrication properties ( until all
the Extreme Pressure and other compounds are added ) other
than those conferred by the viscosity. It is not a "lubricant",
just a base grade.

So, in summary, it is a water-displacing formulation which
deposits a film that provides temporary corrosion protection
( temporary usually means days to months, depending on the
environment).  The 40 is supposed to mean that it was the
40th formulation evaluated - not certain if true or not.

             Bruce Hamilton

Newsgroups: sci.chem
Subject: Re: WD 40 Ingredients
From: rtore00@pop.uky.edu (Professor Robert Toreki)
Date: 10 Jun 1997 12:50:44 GMT

I answered this a while back...Here it is again, courtesy of Deja News:

>Subject:      GC-MS analysis of WD-40 (was Re: WD-40: what's in it?)
>From:         rtore00@pop.uky.edu (Rob Toreki)
>Date:         1995/07/03
>Message-Id:   <3t9hed$94t@service1.uky.edu>
>Newsgroups:   sci.chem,sci.materials,sci.engr
>
>As I don't recall seeing a decent answer yet in this thread, I shot
>some WD-40 into a vial of ether and then shot the sample into my GC-MS.
> This minimal analysis will have missed any nonvolatile species
>(inorganics, polymers) as well as any components (propellants etc.)
>with approximately the same volatility of ether (the detector is shut
>off during passage of the solvent front).  I then matched some of the
>major peaks against our computer's 138,000 compound database.
>
>The GC-MS shows about 45 different components in the C9-C11 range.
>Decane and undecane are the two largest peaks in the spectrum.  Most of
>the C9-C11 appear to be straight or minimally branched hydrocarbons,
>although one peak had a pretty good match for decahydronaphthalene.
>C9-C11 make up approximately 99% of the detected signal, but I also
>picked up a small amount of higher alkanes such as hexdecane and
>eicosane (C16-C20 range).  Overall, it doesn't quite match Merck's
>desription of kerosene, but the idea is more or less the same.

The kerosene reference was in response to another reader's suggestion.
Bruce Hamilton also pointed out that if there were any non-volatiles
you could easily test for it by evaporating the solvent.

Enjoy.

Rob

-----------------------
Professor Robert Toreki, Dept. of Chemistry,  University of Kentucky.
Inorganic, Organometallic and Materials Chemistry while you wait.
rtore00@pop.uky.edu   Way cool web server: http://www.chem.uky.edu/
Major research funding cheerfully accepted; inquire within.

Newsgroups: sci.chem
Subject: Re: WD 40 Ingredients
From: B.Hamilton@irl.cri.nz (Bruce Hamilton)
Date: Fri, 13 Jun 1997 10:18:38 +12

Well, I'll be a little crass and add to my post.

In article <...> B.Hamilton@irl.cri.nz (Bruce Hamilton) writes:
>The WD stands for Water Displacing. I haven't analysed it,
>( not commonly sold here ) but somebody ( Professor Toraki? )
>squirted some down a GC/MS and confirmed the solvent was
>boiling around 150-200C and only contained a minor % of
>aromatics, which means it is either a narrow boiling range
>kerosine fraction, or a special narrow boiling range solvent
>like low aromatics white spirits.

It is listed as Stoddard Solvent - which is actually a low aromatics
White Spirit. It would have a boiling range between 150C - 200C
and an aromatics content below 20%. According to various
sources, the typical liquid product contains:-

70% low aromatic white spirits ( stoddard solvent )
~20% lubricant base grade ( solvent de-waxed, paraffinic type )
<10% of corrosion inhibitor ( some formulations use 2 inhibitors,
   normally they would only be present at low concentrations, so
   it's possible that the inhibitor could be something crude like
   an oil that produces a hard film with synthetic additives )
<5% of wetting agent ( probably quite low concentration, other the
   formulation would emulsify some water which could affect the
   protective film's durability and performance )
<5% of fragrance.

The aerosol versions adds 25% of LPG as propellant to the above
( probably with less of the wetting agent to minimise foam )

My earlier suggestions aren't too different from the above.

             Bruce Hamilton