The Complete Screen Printing Process Explained

What is Screen Printing?

Screen printing (also called silk screening or serigraphy) is a printing technique where ink is pushed through a mesh screen onto a substrate—typically fabric, but also paper, wood, glass, metal, and plastic. It's one of the oldest and most versatile printing methods, dating back to 10th century China where silk mesh was used as the screen material.

The fundamental concept is simple: create a stencil on a mesh screen, then force ink through the open areas of the stencil onto the material below. What makes modern screen printing powerful is the precision, repeatability, and vibrant results this process achieves.

Why Screen Printing Remains the Industry Standard

Despite the rise of digital printing methods like DTG and DTF, screen printing remains the dominant choice for custom apparel—especially for bulk orders. Here's why:

• Durability: Properly cured screen prints can withstand 100+ washes without significant fading or cracking
• Vibrant colours: The thick ink layer creates bold, opaque colours that pop—even on dark garments
• Cost efficiency at scale: Once screens are made, the per-unit cost drops dramatically with quantity
• Versatility: Works on almost any flat surface and with specialty inks (metallic, puff, glow-in-the-dark)
• Consistency: Produces identical results across thousands of prints

Every screen print begins with artwork—and not just any artwork. Screen printing has specific requirements that differ from digital printing methods.

File Requirements

Having the right file format makes a significant difference in print quality and turnaround time. For a complete overview, see our File Types Guide.

• Vector files preferred: AI, EPS, or PDF with outlined fonts scale infinitely and separate cleanly
• High-resolution raster: If using photos or complex graphics, minimum 300 DPI at actual print size
• Colour separation: Each colour in the design becomes a separate layer/screen
• Spot colours: Designs should be in Pantone (PMS) colours for accurate matching, not RGB or CMYK

Colour Separation

Unlike digital printing which blends colours automatically, screen printing requires separating each colour into its own layer. A 4-colour design means 4 separate film positives, 4 screens, and 4 print passes.

Separation Type	Description	Best For
Spot Colour	Each colour is pre-mixed and printed as a solid	Logos, text, bold graphics
Simulated Process	Uses halftone dots in 6-8 colours to simulate full colour	Photorealistic images on dark shirts
CMYK Process	Four transparent inks create full colour via halftone dots	Full-colour photos on white/light shirts
Index Colour	Limited palette with small square dots (no overlap)	Vintage/artistic effects

Once artwork is separated by colour, each colour layer is printed onto transparent film. These film positives act as the stencil template for creating screens.

Film Positive Requirements

• Dense black coverage: The black areas must be completely opaque to block UV light during exposure
• One film per colour: A 4-colour design requires 4 separate film positives
• Registration marks: Cross-hairs or targets printed on each film ensure precise alignment
• Printed on inkjet film: Special waterproof transparency film designed for screen printing

Modern print shops use high-quality inkjet printers with RIP (Raster Image Processing) software to output film positives with precise halftone dots and registration marks. The quality of your films directly affects the quality of your final prints.

Screens are frames (typically aluminum) stretched with a tight mesh fabric. The mesh count—measured in threads per inch—determines what kind of details and ink deposits the screen can handle.

Mesh Count Selection

Mesh Count	Ink Deposit	Detail Level	Best For
110 mesh	Heavy/thick	Low detail	Underbases, bold text, athletic printing
156 mesh	Medium	Medium detail	General purpose, most spot colour work
200-230 mesh	Light/thin	High detail	Halftones, fine detail, water-based inks
305+ mesh	Very light	Ultra-fine detail	Process printing, ultra-fine halftones

Coating with Emulsion

The screen is coated with a light-sensitive emulsion in a darkroom or low-light environment. Using a scoop coater, the emulsion is applied to both sides of the mesh in thin, even layers. The screen is then dried completely in a dark, dust-free environment.

This is where the magic happens. The film positive is placed on the coated screen, and both are exposed to UV light. The light hardens the emulsion everywhere except where the black film blocks it.

The Exposure Process

1. Position the film: The film positive is placed emulsion-side down on the screen, perfectly aligned
2. Ensure contact: A vacuum or weight ensures the film is in tight contact with the screen (no light gaps)
3. Expose to UV: The screen is exposed to UV light for a precise duration (varies by emulsion and light source)
4. Hardening occurs: UV light hardens (crosslinks) the emulsion, making it water-resistant

Washout (Developing)

After exposure, the screen is sprayed with water. The areas blocked by the film—which didn't receive UV light—remain soft and wash away, creating open areas in the mesh. The exposed areas stay hardened, creating your stencil.

After washout, screens are inspected for pinholes (tiny unwanted open spots) and touched up with blockout fluid if needed. The screen is then dried completely before printing.

With screens ready, it's time to set up the press. Multi-colour designs require precise alignment (registration) so that each colour prints in exactly the right position relative to the others.

Press Types

• Manual press: Operator controls each print stroke; ideal for short runs and specialty work
• Automatic press: Mechanized printing with consistent pressure and speed; essential for large orders
• Carousel press: Multiple print heads rotate around a central point; most common configuration

Registration Process

Each screen is mounted on the press and adjusted until the registration marks align perfectly. Test prints are run on scrap fabric or paper to verify alignment before production begins. For multi-colour work, even a fraction of a millimetre off creates visible misregistration.

The actual printing is surprisingly quick once setup is complete. The garment is loaded onto a platen (flat printing surface), the screen is lowered, ink is applied, and a squeegee pushes the ink through the open mesh areas.

The Print Stroke

1. Flood stroke: The squeegee pushes ink across the screen, filling the mesh
2. Print stroke: The squeegee presses down, forcing ink through the stencil onto the garment
3. Screen lifts: The screen separates from the garment, leaving the printed image

Multi-Colour Printing

For designs with multiple colours, the process involves printing one colour, flash curing (partially drying with a heat source), rotating to the next print station, and repeating. The flash cure "gels" the ink so subsequent colours don't smear or mix.

Printing on Dark Garments

Dark shirts require an additional step: printing a white underbase first. This layer of white ink creates an opaque foundation so that colours appear vibrant rather than being absorbed by the dark fabric. The underbase is flash cured before printing the top colours.

Learn more about different ink options in our Screen Printing Ink Types Guide.

Curing is arguably the most critical step for print durability. Unlike air-drying, curing involves heating the ink to a specific temperature that causes a chemical change, permanently bonding the ink to the fabric fibres.

Curing Requirements by Ink Type

Ink Type	Cure Temperature	Cure Time	Notes
Standard Plastisol	320°F (160°C)	45-90 seconds	Ink must reach full temp throughout
Low-Cure Plastisol	270°F (132°C)	60-90 seconds	For heat-sensitive fabrics
Water-Based	320°F (160°C)	2-3 minutes	Requires full evaporation of water
Discharge	320°F (160°C)	90-120 seconds	Activates bleaching agent

Curing Equipment

• Conveyor dryer: Garments move through a heated tunnel; standard for production
• Flash dryer: Used between colours; partially cures (gels) ink
• Heat press: Can cure single pieces; less common for screen printing

Every quality print shop inspects finished garments before shipping. This catches any defects before they reach the customer.

Quality Checkpoints

• Print coverage: No pinholes, voids, or thin spots in the print
• Registration: All colours aligned properly; no visible gaps or overlaps
• Colour accuracy: Colours match approved proof or Pantone reference
• Cure test: Stretch test (properly cured ink stretches without cracking)
• Garment condition: No stains, damage, or defects in the blank
• Placement: Print is centered and positioned correctly (see our Print Locations Guide for standard placements)

Screen Reclamation

After the job is complete, screens can be reclaimed for reuse. A chemical emulsion remover breaks down the stencil, which is then pressure-washed out. The clean mesh can be recoated and used for the next job. Well-maintained screens can be reclaimed hundreds of times.

Frequently Asked Questions

Related Resources

• Screen Printing Ink Types Explained
• Vector vs Raster Artwork Guide
• DTG vs DTF vs Screen Printing Comparison
• Our Screen Printing Services
• Get a Quote