Silk Screen Printing T Shirts

First: Confirm the design vector file (AI, EPS, PDF) or high-resolution bitmap (300 DPI or higher).

Processing: Separate colors into printing plates (one screen per monochrome); if gradients or photographs are included, consider color separation or offline processing (lamination/gradient halftone dots).

Select Fabric: Confirm the fabric type (cotton, polyester, blends, stretch fabrics, etc.), color, and finishing (coatings, waterproofing, etc.). Test with a sample garment first to avoid color differences or adhesion issues between the finished product and the sample.

Select Inks and Additives: Select the ink type based on the fabric and requirements (e.g., general PVC/silicone/elastic silicone/environmentally friendly water-based or low-temperature curing formulations). Select the appropriate formulation and record the mixing ratio.

Select Mesh: Large blocks of color or thick paste: Low mesh (e.g., 40–80T) to facilitate the passage of thick paste; Details or high precision: High mesh (e.g., 120T, 156T) to maintain sharp edges.

Note: Elastic fabrics usually also require a lower mesh to ensure adhesion.

Emulsion Application and Exposure: Apply the photosensitive emulsion evenly to a clean screen and dry in a darkroom.

Exposure using a screen-making machine or exposure lamp for the designed exposure time (adjust the time according to the emulsion and lamp source).

After exposure, rinse and develop with water, checking for sharp edges and no leakage.

Screen Repair and Edge Sealing: Check for small holes or rough edges in the image, repairing with repair fluid if necessary.

Seale the edges of the screen to prevent paste leakage, install the frame, and test the tension.

Mix inks according to color charts or samples.
a. Visually inspect and calibrate using a standard color chart (Pantone or customer-specified sample), if applicable.

b. Keep records (batch number, additives, dilution ratio) for subsequent mixing.

Strike-off sample printing.
c. Print on a sample fabric to check color, opacity, dot stretch, and detail reproduction.

d. If printing on dark fabric, apply a white underbase and check coverage.

Secure and position the garment.
a. Place the T-shirt flat on the pallet and secure it with positioning clips or tape.

b. Registration: For multi-color printing, ensure each color screen is correctly registered (aligned) to avoid misalignment.

c. Set the screen height and squeegee angle.

d. Adjust the screen-to-fabric off-contact distance to a suitable level. The squeegee angle is usually around 45°, fine-tuned according to ink viscosity.

Inking and Squeegeeing: Pour an appropriate amount of ink onto the screen and squeegee it evenly in one pass (bottom squeegee + top squeegee) to ensure a consistent ink layer.

For thick ink or special effects, multiple ink applications or overprinting may be necessary.

Item-by-Item Inspection: Perform random checks on the first 5-10 items of each batch to inspect for coverage, edges, details, color difference, and position.

Multi-Color Sequence: From light to dark or from bottom to top (depending on the process), paying attention to the curing or pre-drying time of each color to avoid color mixing or smudging.

Choose a suitable curing method. Commonly used: conveyor belt dryer (hot air curing) or hot press/hot air gun (small batches). Note: Curing conditions vary depending on the ink formulation; follow the ink manufacturer's instructions.

Cure Quality Inspection: After curing, perform hand feel, tensile, and care label tests. Common tests include: scratch test, 50-wash simulation, and tensile test (no cracks in the printed layer).