Etching Technology For Making Stainless Steel Filters

Firstly, the mesh size of the filter varies, and the thickness of the material determines the manufacturing method and processing accuracy of the stainless steel filter. Senloong offers a wide range of stainless steel filter products, with filter material thicknesses ranging from 0.05mm to 1mm and mesh sizes up to 0.1mm.

Etching process flow of stainless steel filters：

 

1. Surface pretreatment

Cleaning: Use acetone and alcohol to ultrasonically clean stainless steel foil and remove grease.

Dehydration drying: Dry in a 100 ℃ oven for 10 minutes to avoid moisture affecting the photoresist.

2. Apply photoresist

Uniform coating: Drop photoresist onto the metal surface, and rotate the coating machine at 1000-3000rpm to form a uniform coating film.

Pre baking: Bake at 90-100 ℃ for 1-2 minutes (to remove solvents and enhance adhesion).

3. Exposure and development

Mask alignment: Place the designed filter pattern mask tightly against the surface of the photoresist.

Pattern design: The aperture and spacing need to consider the lateral corrosion caused by etching, and the aperture is usually designed to be 10% to 20% larger than the target.

Exposure: Exposure to UV light for 5-60 seconds, depending on the thickness of the adhesive and the intensity of the light source.

Development: Soak in developer solution, dissolve the unexposed part, and expose the metal substrate.

4. Etching

Etching solution immersion: Place the developed metal into an etching solution, such as 40 ℃ FeCl ∝, with a corrosion rate of about 10-50 μ m/minute.

Neutralization and cleaning: After etching, neutralize the residual acid solution with NaOH solution or clean water.

5. De gluing and post-processing

Remove photoresist: Use acetone or specialized photoresist remover to peel off the remaining photoresist.

Polishing: If necessary, electrolytic polishing is used to reduce burrs on the edges of the hole.

 

As shown in the figure below, the stainless steel filter screen made by etching process has dense and uniform mesh holes. At the same time, it does not have any impact on the material of the product. No heat is generated during the processing, and it will not cause deformation or distortion of the filter screen. The aperture accuracy can reach different levels depending on the thickness of the material, and currently can stably achieve an error of plus or minus 0.02mm.