Why is white ink so difficult to print?Updated 2 hours ago
There are several reasons white ink can be difficult to print, and before making adjustments, it's important to understand that white ink needs to be thicker and more opaque than most other colors to provide good coverage. White ink relies on a high concentration of pigment to create an opaque print, so thinning it too much can reduce its coverage and opacity. This can leave your print looking faded, transparent, or more vintage than intended.
How to Tell If Your White Ink Is Too Thick
Before reaching for a reducer, start by checking the temperature of your ink. Plastisol ink can become noticeably stiffer in cooler temperatures, making it harder to push through the screen. Allow the ink to reach a comfortable working temperature, around 80°F, and mix it thoroughly before printing. This can help improve its consistency without changing the ink's formulation.
If your plastisol ink is still too thick to print comfortably, check the manufacturer's recommendations before adding a curable reducer. If the ink is compatible with one, start with a very small amount and mix thoroughly. A starting point of 1-3% by weight may be appropriate for some products, but the recommended amount varies by ink. Avoid exceeding the manufacturer's maximum, as adding too much can compromise opacity, coverage, and cure times. Always test print after making an adjustment.
Be careful about adding reducer to cold ink. Cold ink can feel much stiffer than it will at normal working temperatures. If you add reducer before allowing the ink to warm up, you may add more than necessary. Once the ink reaches its working temperature, it could become too thin, reducing the opacity and coverage you're trying to achieve.
What About Water-Based White Ink?
Water-based inks, such as Green Galaxy Comet White, behave differently from plastisol inks and require different adjustments. Avoid applying excessive heat directly to the ink, as this can cause water to evaporate and the ink to dry out. Keep the ink mixed regularly during production to help maintain a consistent working texture.
If Comet White feels too thick, check the product's recommended mixing instructions before making adjustments. Depending on the specific formulation and the issue you're experiencing, a compatible additive or a small amount of water may help. However, adding water or clear base can affect the ink's consistency and printing performance, so use only manufacturer-approved additives and amounts. Don't assume that a reducer intended for plastisol ink is suitable for water-based ink.
Understanding Different Plastisol Ink Textures
Not all plastisol inks have the same consistency. Two terms you'll often hear are short-bodied and long-bodied. These describe how an ink behaves when it's moved or sheared, rather than simply how thick it is.
Short-bodied ink: Tends to break and flow more readily under the pressure of a squeegee, often making it feel smoother and easier to print. FN-INK is known for its smooth, creamy consistency.
Long-bodied ink: Tends to feel more elastic or stringy and may resist movement differently under a spatula or squeegee. Some formulations can feel especially stiff when cold and become easier to work with as they warm up. Certain Wilflex inks may behave this way, depending on the specific product.
Keep in mind that ink behavior varies by formulation, and not every ink within a brand will have the same body or printing characteristics. Temperature, mixing, mesh count, stencil thickness, and squeegee technique can all affect how easily white ink prints.
To learn more about handling white inks in cooler temperatures, read this article.