〔Screen Printer〕How is a screen printing screen made?

The production of screen printing screens mainly includes the following steps and methods: 

I. Classification of Plate-Making Methods 

- Direct Plate-Making Method 

Process flow: Mesh stretching → Degreasing → Drying → Photoresist coating → Exposure → Development → Drying → Plate repairing → Mesh sealing 

Feature: Photoresist is directly coated on the mesh, suitable for high-precision printing 

- Indirect Plate-Making Method 

Process flow: Indirect film exposure → Hardening → Development → Laminating to mesh → Blow-drying → Plate repairing → Mesh sealing 

Feature: Transfer via pre-made photoresist film, suitable for complex patterns 

- Direct-Indirect Hybrid Plate-Making Method 

Process flow: Transferring photoresist layer to mesh → Drying → Peeling off base film → Exposure → Development 

Feature: Combines advantages of direct and indirect methods with high stability 

II. Key Process Details 

- Mesh Stretching & Tension Control 

Aluminum alloy frames are dominant; tension must be uniform (20-30N/cm²). 

Polyester/stainless steel meshes: High mesh counts (100-500) for fine printing. 

- Photomaterial Coating 

"2+2" double-sided coating to fill mesh holes; "0+4" for thickening the printing surface. 

SBQ single-liquid photoresist achieves a resolution of 50μm. 

- Exposure & Development 

Vertical UV irradiation; check ink passage rate after development (graphic area >98%). 

Moderate water pressure to avoid photoresist film damage. 

III. Material Selection 

- Mesh Types: 

Nylon (3% elongation): For curved surface printing. 

Polyester (solvent-resistant): For high-precision graphics. 

Stainless steel (100,000-print durability): For long-term mass production. 

PI film screens: With neat edges, line width can be below 15μm. 

IV. DIY Simple Process (for beginners) 

Coat photoresist after mesh stretching (light-proof operation). 

Expose film (5-20 minutes with UV lamp). 

Rinse for development and repair edges. 

Print with water-based/oil-based inks. 

V. Quality Control 

Exposure requires anti-light scattering devices.  

High-temperature baking of metal plates enhances adhesion. 

Knot-free meshes reduce ghosting and grid breaking. 

For specific processes (e.g., LTCC circuits or photovoltaic grid lines), further optimization of tension and film thickness parameters is required.