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The Truth About Latex
We have spoken with many people
representing many companies about latex--how it’s processed, what’s added to
it, how it’s shipped, how it’s tested, what all the numbers mean—and we know
how confusing it can be. It’s partly because we are thousands of miles from
rubber farms and partly because companies pitch whatever they sell as the
best and everything else as inferior. |
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Let’s start with what everyone seems
to agree on:
- Rubber trees grow only within
about 10 degrees of the equator, and they grow best on hilly slopes.
- The trees are sliced at an angle,
and a small amount of serum is collected daily.
- The trees can be sliced about 180
days per year. During the rainy season and in the summer trees cannot be
cut. The trees are cut about 3 feet in length, and the serum runs for
about an hour. The tree heals in about an hour and the serum stops
flowing.
- Latex was originally harvested in
Brazil, but for a variety of reasons the only rubber trees in Brazil these
days are wild and not cultivated. Almost all latex nowadays comes from the
far east.
- When the serum is harvested, it is
about 1/3 dry latex content. In other words, it is mostly water.
- The latex in the pure state needs
to be processed. (The processing is not like maple syrup. Maple
syrup is boiled down from watery sap to a thicker, sweeter syrup, then
filtered.)
- All but one company we have asked
has told us that a small proportion of ammonia is added to the serum so
that it does not coagulate. (One company told us that their factory is
next to the farm so they process it right there. Because latex is grown
in the countryside and because it coagulates so fast, it’s hard to imagine
a factory in a 3rd world country next to a farm. So we have concluded that
everyone adds ammonia at first.) Ammonia is a naturally occurring product
and is washed out later in processing.
- From here the latex needs
to be expanded and concentrated. This is done by adding ingredients and
whipping or frothing or centrifuging the material.
- Latex has in
it natural proteins that some people are allergic to. Everyone says that
their process, whatever it is, washes out the proteins, and this is
verified by testing.
How the expansion and concentration
happen, what ingredients are added, and working conditions on the farm—these
are all things we are still investigating:
- What’s added? We’ve heard lots of
things—sulphur, soap, anti-oxidants, food grade anti-oxidants, gelling
agents, and “other” chemicals.
- Fair Trade? Everyone says that
their plantation is family owned, that there are no child workers, and
that all the workers receive a fair wage. This is difficult to verify.
- Dunlop Process vs. Talalay
Process? Talalay is a process used when frothing the latex. The
process involves vacuuming the latex while it is being frothed, then
freezing it to stabilize the material. This process is more
expensive than the Dunlop process and it makes sense that it produces a
more consistent product as some of the weaker air bubbles in the latex are
removed. In the Talalay process chemicals are usually added, but not
always. It is possible to make natural Talalay, synthetic Talalay, natural
Dunlop, and synthetic Dunlop. This is where it gets confusing.
- What’s better? All Dunlop process
companies claim that their product is purer and superior to Talalay
process companies, and all Talalay process companies claim that their
product is more consistent and therefore superior to Dunlop process
companies…and they all have reasons to back it up.
- What other variables are there?
Some companies add “fillers” such as clay to make the latex go
further. (If you find a queen size natural latex mattress selling for
$1200 or less, there are fillers.) Some companies use “perimeter
support.” That means they use cheaper materials, usually chemical, around
the outside of the latex. This does allow you to sit more easily on the
side of the bed. It also reduces the sleeping surface by up to 20%.
- What if I want 100% pure, natural
latex? You are probably going to find at best 98% or 99% natural latex or
salespeople stretching the truth.
- What’s left in the 1% or 2% that’s
not latex? Of course everyone says it’s harmless which it probably is.
However, because it’s the same thing that memory foam guys and synthetic
guys say, we are still investigating and getting test results and spec
sheets. We feel that testing the end product is what matters most, not how
it’s processed.
- How will the 1.5% other materials
affect me? What is left is likely to be sulfur and other natural
stabilizing compounds; their effect should be negligible for almost
everyone. Moreover, we think that latex is the best sleep surface because
of its pressure relieving quality, and improved sleep outweighs any
possible negative effect of a tiny bit of non-rubber material.
- How does it affect the life of the
mattress? Whether it’s Dunlop or Talalay, natural latex or synthetic, and
you like the feel of it, your mattress is going to last a long time. Latex
mattresses made in the 1950s lasted 30 years and longer. Latex is
extremely durable. If you are happy with your mattress for 10 - 15 years
or longer, you’ve made a great purchase. Longer warranties like 20 or 30
years are more about marketing than reality. How long it lasts depends on
a number of factors—how it’s made, of course, but also about how it’s
used, who is using it, etc.
Want to read WHAT goes into
our latex?
Dunlop Proces Eco Report
Natural Talalay
Guarantee |