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Need help in Identifying this resin 1

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May 8, 2013
6
PH
Hello,

This is my post here, i heard great things about this forum.

I make plastic varnish here in the Philippines . This is made up of Almaciga resin ( Manila Copal) combined with strong lacquer thinners. Uses of this Plastic Varnish is as a substitute for the more expensive Clear Gloss Lacquer. Used on Wood and Rattan Products. I have secured another source of Almaciga resin and the good thing is i am the exclusive buyer. My problem is that in the production of Plastic varnish, this new resin obviously from another place in the Philippines, does not dissolve completely in Lacquer thinner. Instead it turns into gel. Unlike the Almaciga from Palawan which can easily be dissolved.

I am thinking it is another kind of resin that natives here mistakenly identified it a as Almaciga. Its main difference is the color . this new "Almaciga" is whiter or paler and less shiny than the our Approved Almaciga which is more darker yellow color and much shinnier.

Hope you guys can enlighten me on this buffling question.


Chris
 
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Lots of variation, even just within Copal resin. If it even is Copal. Older semi or fully "fossilized" Copal tend to be darker and harder.

You can get more information by having a good natural resins guy perform FTIR on each sample and compare them. Of course, a good natural resins guy will probably look at the samples, sniff them, fiddle under a microscope with some solvents and give you an answer faster than the FTIR.

Given your solubility characteristics, your source is pretty obviously not the same stuff.

Can you make it work with a different solvent system? Does it form a good hard film when dry? Or a "good enough" film? Is the lower cost worth the hassle?
 
Second thought - does the resin still need to be fused, or "run"?
 
It dries to a hard film unfortunately it does not form a clear film, i agreeits not from the same specie,

Regarding natural resins guy where can we find him? I already approach guys in the Philippines , scientist actually and they could not give a solution.

Hope to hear from you soon,


Chris
 
Copal is usually processed to increase solubility, and the process is usually referred to as fusing, or in common terms being "run." My references give an estimate of 25% mass loss on fusion, but no details on the process itself. Likely some type of heating/cooking process.
 
Our process is quite simple, no cooking or heating needed. We just take certain amount of copal almaciga , then mix it with lacquer thinner , then let it stand over night , the following day we filter the bark, dirt and other impurities. Filter using silkscreen cloth, then we have plastic varnish , its that simple.

So thats why we have problem with this new resin that would not easily dissolve in lacquer thinner.

Thanks for the info about fusing and run

Hope to hear from,

By the way another guy by seeing the picture,says its more of a gum damar

Chris
 
Yes, your supplier of the original resin could be taking care of the fusion, while your new source is supplying raw resin.
 
Dear tom,

Both resin are from natives , taken from tapping trees, but they are from diffferent places in the Philippines
 
Hi there,

It looks as though you have a higher molecular weight resin although it is of the same type, I have seen this is supposed equivalent grades of epoxy resins.

It looks like we need several tests to ensure the NATURAL product is at least within some spec before using it;
1. Each batch of resin must be tested so start by listing the parameters of a typical sample.
2. Always test before use.
3. Now that we have a standardised product we can look at replacement or alternative sources.
4. The thinners should also be QC'ed for cutting power on each batch or delivery

On the point of solubility you can add 5% Butanol or Toluene to the lacquer thinners. 3% MEK anded to the standard thinners is really great for boosting the cutting power of lacquer thinners.

On the point of film clarity things get a little tricky but you could try a small amount of plasticizer such as Dibutyl Phthalate or similar but not a natural oil such as linseed as overcoating could be a problem with such a strong solvent.

Remember that 0 to 5% plasticiser is what we are talking about. I consider any addition of >5% a change to the system and not an addition.
Regards, Ken.
 
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