Using 2 paint colors in a room, what is product to paint over painters tape to give a clean sharp line?

I have seen on home repair shows that there is a product that you can paint over the edges of painters tape. When you do, it keeps the 2nd color from bleeding onto the first color. The demarc line between the colors is crisp and very, very clean.Using 2 paint colors in a room, what is product to paint over painters tape to give a clean sharp line?
I have never seen this product, if it is aviailable they should know what it is at Lowes, Menards or Home Depot, or any hardware store. The most important thing is to make sure the tape is down good and tight on the edges and to remove while the paint is still wet to avoid peeling the paint off.Using 2 paint colors in a room, what is product to paint over painters tape to give a clean sharp line?
I learned the hard way (by doing it wrong first) how to make clean crisp lines. You can either paint over your tape line with clear acrylic or what I found easier was - paint the base color (lighter color) and let it dry. Put up your tape lines. Then just paint that base color along the tape so it's overlapping the tape. Let that dry and then paint your second color. Remove the tape before the second color is dry. Painting the base color over the tape seals the line so the second color can't bleed through. We painted vertical stripes in our dining room before we learned this method. We just taped the lines and painnted. The second color bled so we had to touch up each individual line with an artist's brush. It took forever! Looks nice now but I wish I would have known before we started.
I haven't seen it, but it sounds like a good idea. I would imagine it would be something like a clear acrylic, matching the gloss index (i.e., Matte, Satin, Flat, Semi-gloss...) of what your color paint is. What it would do, now that you mention it, is seal those little areas where the paint bleeds under---and it always does. The trick would be that it wouldn't pull up the paint when you're done. Yes, blue ';delicate surface'; tape. But the treatment itself may be something other than acrylic, like maybe a fixative, which is less glue-like. I'll be watching this to see if anyone actually gives the correct answer. Good Luck.
I don't think it's anything special just a regular roller. It is a blue painter's tape that is rolled and packaged like masking tape but it's blue and you'll find it in the painting section. The trick is to make sure one layer of paint is dry before you apply the second color and make sure the tape is seated securely first.
You can use a satin clear coat to prevent seepage. This can really help you when you are doing lines on walls that are not perfect. I got extra sharp lines after using this method after watching it on a home %26amp; garden show.