[Claudia Eicker]

Claudia Eicker  asked the Naked Scientists:
   
Hi Chris
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For the past few years, we've made trophies for a client.  Each trophy is a resin ball inside which a sheet of clear acetate with a logo printed on it is set.

This year, for no apparent reason, the acetate seems to be disintegrating; tiny bubbles form and then that part of the acetate seems to disappear.

Whereas in previous years, the acetate has been clear with only black ink used for the logo, the logo this year is primarily purple and maybe the purple ink is what's having this effect?

But where do these pieces of purple acetate go?  Or is it just the ink that's being "eaten" by the resin?

Can you solve the mystery of the acetate-eating resin??
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Thanks
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Regards,
Claudia

What do you think?

[Horseradish_5000]

From you description it sound like there's definitely a reaction happening.

If it just the dye that's affected perhaps you could protect it with another layer of acetate?

Think I would need more info on your process and more detail about the reaction how fast it was etc. To really tell what's happening.

[RD]

Possibly the ingredients of the (polyester ?) resin were not sufficiently mixed this year,
and an unmixed, unset, chemical ingredient is reacting with the encapsulated item.
(or perhaps the ratio of ingredients was different this year, e.g. too much catalyst).

Dilute solutions of 30 to 60% MEKP are used in industry and by hobbyists as the catalyst which initiates the polymerization of polyester resins used in glass-reinforced plastic, and casting.
 MEKP is a severe skin irritant and can cause progressive corrosive damage or blindness.

http://en.wikipedia.org/wiki/Methyl_ethyl_ketone_peroxide

Organic peroxides, like their inorganic counterparts, are powerful bleaching agents.

http://en.wikipedia.org/wiki/Organic_peroxide