How to mask imagepac

Masking is a useful way of making your stamps be separate on the sheet. To do this you use two negatives, the upper, or masking one is an outline of the stamps with the area outside the outline coloured black.

This double negative technique avoids the need to cut out stamps manually.  This is particularly useful in organisations where they make a lot of the same size of business stamps, for automatically cutting out the centre of daters or cutting around difficult shapes such as circles or ovals, and of course for making craft stamps.  This is very powerful for the hobby and craft market where the finished sheet can be sold to the user, straight from the machine. The crafter can just peel the stamps off, mount them onto an acrylic block, stamp them, and replace many times for storage. The back will stay sticky for ever, as long as it’s not subjected to excessive light.

Step 1
When you are typesetting your negative create a second negative with just the outline surrounding each design.  Widen the outline by about 5mm and make the area outside this outline black. This can be done with a click with Corel or any artwork modifying program using the magic wand function. Print this second masking negative to create a matched pair with the original one.

Step 2
Place your negative down on the exposure bed so that you can read the text as normal.  Lay your imagepac sachet on top of it as normal.  Place the second ‘mask’ negative on top of the sachet so that the two negatives line up exactly when you look through them.  Close the upper glass. If you are running this process many times you can tape the upper and lower negatives in place.

Step 3
Expose front and back (the back exposure time will have to be increased to account for the extra negative stopping a bit of light).  Then process as normal- wash out in hot water with wash out agent and post expose as normal.  Do not wash out for too long or leave under water too long as the stamps are separated and can be swollen easily with water.

Step 4
Peel the stamps of the sheet and attach to the self-inkers, or sell the sheet to customers for them to peel off and use themselves.