Is there a chemist in the house

I dyed some Trispi sails using Rit Dye. I had to simmer them for about an hour. The dye took quite well and I was pleased. I assembled the sails (6 pieces) with 3M double-sided carpet tape. I cut this tape to 1/4 " and use this tape on all my sails. It hasn’t failed me til now. After about a month or so the dyed sails come unstuck. This happens in the sail box. It hasn’t happened while sailing but this is my “B” rig and I don’t use it much. I thought that the dye left some kind of oil or something on the sails so I wiped the joints with laquer thinner and on another occaision with alcohol.When I put the sails away for the winter I made sure they were all slackened off and when I opened the box for this year one of the seams had come apart. This has never happened with the un-dyed sails. Anyone have any ideas?

Vancouver Island

I sounds like the dye wasn’t set in permanently, which sounds tough on plastic. Remember coloring eggs? That uses vinegar to color (low pH). Maybe easter egg dye will be better? LOL

my 2 sense. I’m a lubrication/soap chemist.