What is Discharge Screen Printing?

What is Discharge? - Screen Print Direct

Discharge printing. A lot of printers have heard the term but don’t know what it is or understand exactly what it does. In this post we will discuss what discharge printing is, why printers love it, the differences between standard and fluorescent discharge inks and how to use it.

What is Discharge Printing?

Discharge screen printing is a specialized method of screen printing used in the textile and apparel industry to create designs on fabric. Unlike traditional screen printing, which involves applying ink on top of the fabric, discharge printing removes or discharges the dye from the fabric to create a design. This results in a soft and breathable print that is often preferred for high-quality, long-lasting designs on garments. This process is done with water-based ink and requires the addition of a discharge activator. Screen Print Direct offers standard water-based discharge ink and fluorescent colors.

Why use water-based discharge ink compared to normal water-based ink?

When you are silk screening with water-based inks there are a few things to know.

Softer Feel: Discharge printing results in a much softer and more breathable print. Traditional screen printing typically involves a thicker layer of ink that can feel heavy and stiff on the fabric, especially when multiple colors are applied.
No Additional Layers: In traditional screen printing, multiple layers of ink may be required to achieve the desired color opacity, which can make the print feel thicker and less comfortable. Discharge printing removes the existing fabric dye to create the design, so there's no additional layer of ink on top of the fabric.
Vintage or Faded Look: Discharge printing often produces a slightly faded or vintage appearance, which is popular for creating retro or distressed designs. This can be challenging to achieve with traditional screen printing.
Color Matching: Discharge printing is ideal for printing on dark-colored fabrics because it removes the original color and replaces it with the desired print color. Traditional screen printing on dark fabrics often requires an additional layer of white ink as a base, which can affect color accuracy and feel.
Longevity: Discharge prints tend to be more durable than traditional screen prints because the design becomes part of the fabric, rather than sitting on top of it. This means the print is less likely to crack, peel, or fade over time.
Detailed Designs: Discharge printing is well-suited for intricate and detailed designs, as it allows for fine lines and small details to be printed accurately.

Similarities and Differences between Standard Water-based Discharge Inks and Fluorescent Colored Ink

Fluorescent Ink Under Black Light

Standard Water-based and Fluorescent Discharge Inks share most of the same properties as they are both water-based inks that can be activated with discharge. However there are a few differences worth noting.

Color Mixing System: Screen Print Direct offers a color mixing system for standard water-based ink colors. With these inks you can create 1000’s of different colors found in the Pantone book. Fluorescent inks do not have this ability and are not inks included within this color mixing system.
Opacity: Fluorescent inks are more opaque than standard inks. There is more pigment in these inks giving them the bright vibrant color desired when printing.
UV Reactivity: Fluorescent inks contain pigments that respond to UV light by emitting visible light, resulting in a glowing effect under blacklight or UV light. Standard water-based discharge ink does not have these properties.
Compatibility with Additives: Fluorescent water-based inks can be mixed with additives to achieve specific effects or adjust ink characteristics. However, the fluorescent pigments themselves are less amenable to modification compared to standard water-based inks.
Cost: Fluorescent inks may be slightly more expensive due to the specialized pigments used to achieve their unique colors.

How to use Discharge Activator?

Add 3-5% discharge activatorto your ink. For example, if you have 8oz of ink you will want to add .24-.40 ounces (6.8-11.4 grams) of discharge to your ink.
When using as a discharge ink, add enough discharge powder to the amount of ink you need for the print run. Mix thoroughly to make sure no chunks or grains are visible. Once the activator is mixed in, the product has an eight hour lifespan. Therefore we suggest only mixing enough for the print run on hand, wasted ink is wasted money.
As mentioned above, when you first print with discharge the color will look muted. When you cure it the color will come to life.

Pictured above: Measured ink with activator

Tips when printing with discharge ink:

Printing on a light-colored garment? Use water-based ink straight from the container, no need to discharge the ink
Printing on a dark colored garment? Mix your discharge ink with its discharge activator so it can bleach the shirt back to its original color and dye the fabric with the colored ink chosen.