Zippers leaving brown stain and residue on P2Z?

[abean3 0]

I have a new Phantom 2Z with approximately 25 jumps on it. I did 5 jumps with it this last weekend and when i unhooked it to put it up I noticed a thick brown stain/residue on the flaps that cover the shoulder/arm detachment zippers. The stains and residue were on both sides of the flap. The stains had the same pattern and lines of the zipper. The fabric is neon green parapack. I had all stand up landings and packed on clean carpet so that fabric only came in contact with the zipper and the container which is also clean and brand new.

What could cause this? The zippers are clean and not rusty in the least, but I was located in Delaware and the day was hot and humid.

Any information about the cause, or if this could affect the structural integrity of the fabric would be great.

I washed it with mild detergent in cold water, but it did not help :(

[ifell 0]

I got a new P2z last summer and since then I jump in less than dry conditions (thick clouds, border line rain, humid days and so on) and I also packed on grass and damp carpet... Never had any stains or issues other than the effects of downwind landings

[johnmatrix 21]

I know what you're talking about, the same thing is on mine, which are/were white. I assumed it was just ordinary wear and tear.

[DSE 5]

I have these same stains on most of my rental suits and personal suits. f you're packing in an area with much dirt/debris (even if it appears to be clean) some colors reveal this more than others. It's not affected the integrity of my Ghost, which has over 800 jumps on it, nor my Phantom2's, one of which has about the same number of jumps on it.