Duct, And Other Tapes.

[Khandro]

Why does duct tape not stick to itself on the roll?

[Clanad]

One site states "...The final coating -- the release -- emphasizes an interesting distinction in the world of stickiness: adhesion versus cohesion. In adhesion, one type of molecule is sticking to another type of molecule; in cohesion, one type of molecule is sticking to itself. Tape uses both [source: Scientific American]. The molecules of the adhesive stick to the molecules of the substrate, or adhere, but they also stick to each other, or cohere. If this weren't the case, the adhesive substance wouldn't hold together. The release coating prevents cohesion at the surface of the tape so it can be unrolled easily..."

By the way, one of the most useful products in my shop is WD-40 ... meant as a lubricant, it will clean up the Duct Tape residure, clean ones hands after working in an oily, dirty environment, etc.

Additionally re: Duct Tape... ever twist off a light bulb from its metal base when removing it? After assuring the light fixture is isolated from electricity at the circuit breaker or fuse box, wad a small amount of duct tape into a ball small enough to be pushed into the broken fixture's base with enough left over to hold onto. Just twist it out as you would normally... works great every time...

[Khandro]

Thanks clanad, I have also proved beyond any doubt that it has also removed a verruca from the sole of my foot (details given if required).
The latest research, should anyone other than OG and Builder be interested ; I have abraded the shiny surface using coarse steel wool lubricated with meths, and I then gave it a thin coat of Hammerite quick drying satin radiator paint, which seems to have made a good bond, all I need do tomorrow is glue the paper to it with PVA, which must surely stick to the painted surface. Watch this space! :0)

[heathfield]

The 'release agent' on the backing of most sticky tapes is silicone. Almost impossible to remove.

[Khandro]

The coarse wire-wool and meths worked well enough for it to accept the paint (see above) and I glued thin card to that surface with PVA which has worked well, thanks to all for interest.
Mrs Khandro pleased with her mirror, though having reversed her car into another this morning, my efforts today have not fully received the attention and accolade they perhaps deserve :0)