Tween 20 - 10ml

Tween 20 – Wetting Agent for Alternative Photographic Processes, 10 ml

Tween 20 is a surfactant that reduces the surface tension of solutions. It helps the sensitizer spread evenly over the paper, improves wetting, and facilitates penetration into the paper fibres.

Even a very small amount of Tween 20 can significantly change the way a solution behaves on the paper surface. It helps prevent the solution from beading up and makes it easier to achieve an even coating.

Tween 20 is particularly useful in processes in which the paper is sensitized with a single light-sensitive solution, such as:

• cyanotype,

• Van Dyke brown,

• kallitype,

• platinum and palladium printing,

• other processes requiring an even application of sensitizer to paper.

Tween 20 should not be used for processes such as albumen printing or salted paper printing.

Important

Not every paper requires a wetting agent. With some papers, particularly those that are lightly or delicately sized, Tween 20 may be unnecessary and can even produce undesirable effects. We recommend making a test before preparing the final print.

Recommended working concentration of Tween 20 solution: 20%.

Only a very small amount of the prepared working solution is added to the sensitizer – usually just a few drops, depending on the type of paper and the volume of sensitizer being used.

Volume: 10 ml