-
Packaging compatibility problem
Hi all,
I’ve just finished developing a liquid lipstick formulation for a client and during the stability testing, I’ve noticed an incompatibility with the client’s packaging. On about 50% of the tubes, the “bottlenecks” have developed visible cracks while the remaining tubes seem to be fine. This is after 3 months at 40° C.
I would normally suggest changing the packaging, but the client literally has hundreds of thousands of the tubes in a warehouse (they also sell lipgloss) and asked me if there’s any other way.The tubes are low-density polyethylene and the liquid lipstick formulation is fairly “standard” (Isododecane, a silicone-based film former, carnauba wax and hectorite, phenoxyethanol, ethylhexylglycerin, Vitamin E + various metal oxides, lakes and micas). I’ve done some initial research and can’t find any known incompatibilities with the ingredients and the LDPE plastic.
I was wondering if any of you have had similar experiences with LDPE and if there’s incompatibilities that I have missed or if this is a common problem. Any ideas would be much appreciated.
Thank you!
P.S.: English is not my first language so I’m sorry if I translated anything wrong.
-
7 Replies
-
We have had a similar experience, although not with the product type you mention. In our case it was not an issue of product incompatability, but an issue of defective packaging.
-
Sometimes the manufacturers use a blend of plastics to make it cheaper. You don’t notice except in cases like this. I buy bottles that are not 100% PET and are much cheaper. In this case you can see it, the transparency is not the same, but in the case of hundreds of thousands even less than 1% would make a huge profit.
Send the bottles to a lab.
-
Thank you very much for your helpful replies. That’s definitely something I’m going to investigate.
Quick follow-up question: which material would you deem best for a liquid lipstick with the ingredients I have mentioned? -
if the cracking is random and not consistently reproducible, it does strongly suggest the problem is caused by the workmanship of the packaging rather than the material itself
a systematic incompatibility between the formula and the packaging material would affect all the packs tested, rather than around 50%
-
I agree with Bill. I’d suspect that the plastic mix is inconsistent, and that the solvent is probably leaching out some of the plasticizer, leading to the plastic cracking in areas of high stress/low plasticizer - but I’d need it tested to confirm.
If I’m right, you won’t be able to use these components with any formula containing Isododecane.
If I got to pick, I’d suggest PET for containers, but the cost is high.
-
Phenoxyethanol - LDPE combination.
-
My bet is also on isododecane. Put some packaging into a jar filled with it and see if the plastic deteriorates
.
Log in to reply.