Nazdar Implements G7 Methodology For DTG Printing

The introduction of inkjet printing into the Direct-to-Garment (DTG) market now allows for the implementation of the G7 methodology of colour control. This globally accepted method enhances colour consistency for printing processes on non-standardized substrates like textiles, which fall outside the Characterized Reference Printing Conditions (CRPC) used in commercial offset lithography.

Nazdar’s Pioneering Role
Nazdar conducted the first G7 training focused on inkjet and screen printers in 2009. Nazdar remains the only company to achieve G7 qualification for screen printing. The G7 methodology, endorsed by ANSI and CGATS, ensures neutral gray balance across all CMYK images, making it the most accepted colour control process for substrates beyond CRPC standards.

Application to Screen and Inkjet Printing
Nazdar identified G7 as the ideal colour control process for both screen and inkjet printing, given their unique challenges compared to offset printing on paper. Implementing G7 in DTG printing, however, presents specific challenges, primarily due to the variation in garment substrates.

Achieving G7 in DTG Printing

1. White Point: Most DTG prints are on coloured garments, requiring a white ink base. To meet G7 standards, the target white point should be an L* of 92 or higher.
2. Pretreatment: Proper pretreatment is crucial for achieving a stable white ink layer, with a drying process ensuring the ink gels correctly for subsequent coloured inks.
3. Garment Selection: Ideal garments have a tight weave and high cotton content to reduce fibrillation and dye migration.
4. Hydrophobic vs. Hydrophilic: Garments should be hydrophobic but not super hydrophobic, ensuring the fabric accepts ink without excessive spreading.

Expanded Tolerances
Nazdar worked with IDEAlliance to expand G7 tolerances for DTG printing due to its unique variables. This adjustment allows DTG printing to conform within a tolerance range of 2.5 – 5.0 dE, similar to screen printing.

By integrating the G7 methodology, Nazdar continues to lead in colour control, ensuring predictable and consistent results for the DTG printing industry.