Why Blockout Is Important

Preventing Colour Bleed-Through

Without proper blockout, dark garment colours can dull or alter the printed design. Blockout ensures the printed colours remain accurate and visible.

Maintaining Design Clarity

Blockout helps preserve fine details and contrast, especially in logos and text that rely on sharp edges and lighter colours.

Common Blockout Methods

White Underbase Printing

A white underbase is printed first to create a neutral layer between the garment and the coloured inks. This is a standard blockout method in screen printing.

Blockout Inks

Specialised blockout inks are formulated with higher opacity to prevent dye migration and colour interference, particularly on polyester garments.

Blockout Transfer Films

In DTF and heat transfer printing, blockout films are used to stop garment colour from affecting the transferred image.

Benefits of Using Blockout Techniques

Enhanced Colour Vibrancy

Blockout allows colours to appear brighter and more accurate, regardless of the garment colour.

Improved Print Consistency

By neutralising the fabric colour, blockout helps achieve consistent results across different batches and garment types.

Professional Finish

Blockout contributes to a cleaner, more polished look, which is essential for branded apparel and commercial use.

Printing Methods That Use Blockout

Screen Printing

Screen printing commonly uses blockout through underbases and high-opacity inks, especially for dark garments.

DTF Printing

DTF transfers often include a built-in white layer to provide effective blockout on coloured fabrics.

Vinyl and Heat Transfers

Certain vinyl materials are designed with blockout properties, making them suitable for dark or patterned garments.

Practical Considerations for Blockout

Fabric Type

Polyester and blended fabrics are more prone to dye migration, making blockout especially important for these materials.

Ink Thickness and Feel

Additional blockout layers can increase print thickness, which should be balanced against comfort and flexibility.

Curing Requirements

Blockout inks may require specific curing temperatures to ensure durability without damaging the garment.

Blockout vs Non-Blockout Printing

Printing without blockout may work on light-coloured garments but can lead to dull or inconsistent results on dark fabrics. Blockout ensures reliable quality across a wider range of applications.

Why Blockout Matters in Professional Printing

Blockout is a vital part of producing high-quality custom apparel. For Australian garment printers, using proper blockout techniques ensures colour accuracy, durability, and a professional finish—helping brands stand out on any fabric colour or garment type.