Of course, following the development of SMT, the demand for stencils has also increased, and the steel mesh has followed. Affected by the cost of materials and the difficulty of manufacturing, the original stencil was made of iron/copper, but it was also rust-resistant, and stainless steel stencils replaced them, which is what we call SMT stencil.

     The manufacturing process of the steel mesh includes: a chemical etching method, a laser cutting method, and an electroforming method.

First, chemical etching

    Process flow: data file PCB→film manufacturing→exposure→development→etching→steel sheet cleaning→opening

    Features: It is a molding, faster speed; the price is relatively cheap.

    Defects: easy to form the shape of the hourglass (not etched) or the size of the opening (over-etching); objective factors (experience, pharmacy, film) have great influence, more manufacturing links, large cumulative errors, not suitable for fine pitch stencil manufacturing The manufacturing process is polluted and is not conducive to environmental protection.

Second, the laser incision method

    Process flow: film manufacturing PCB → taking coordinates → data file → data processing → laser cutting → grinding → Zhang Net

    Features: The data manufacturing precision is relatively high, the objective factors have little influence; the trapezoidal opening is good for demoulding; the fine cutting can be done; the price is moderate.

    Defect: Open all the way, the manufacturing speed is slow.

Third, electroforming method

    Process flow: coating the substrate on the photosensitive film → exposure → development → electroforming nickel → forming → steel sheet cleaning → Zhang Net

    Features: Hole wall lubrication, especially suitable for ultra-fine distance steel mesh manufacturing method.