In the circuit boardTechnical specifications of dry filmWhat are they?

  smtChip processing factoryIn order to be able to better select and use dry films, it is necessary to understand the technical properties and indicators of dry films as well as their processability. The following technical requirements of dry films should usually be understood primarily.

(1) Appearance Quality

Chip processing factoryBy visual inspection, the appearance of the dry film should be uniform, transparent, free of runoff, bubbles, foreign impurities, and free of surface scratches and wrinkles. If dry film with these defects is used, it will cause quality problems of the mask or cannot be used. For dry film in rolls, the winding should be tight and the edges neat so that the film can be applied continuously on the laminating machine.

(2) The thickness of the dry film resist layer should be selected according to the purpose of use

 If the resist layer is used for etching, the thickness should be25～30μmIf the resist layer is used for graphic plating, the thickness should be38～50μmIf the resist is used for hole masking, the thickness should be25～50μm. The thinner the resist film used to make ultra-fine printed wire graphics, the better, the higher the accuracy of the graphics made, the general thickness of the resist layer in the dry film is only a dozen microns.

Different usesSUNFDRTThe thickness of the resist layer of the dry film is shown in Table

As you can see from the table, the uses are similar but differentpcbaManufacturersThe thickness of the product varies, the application should be based on the needs and specificChip processing factoryThe product description of the dry film is selected to suit the thickness of the film. The width of the dry film can be cut according to the applicable requirements and the length of each roll Generally not less than100m.

(3) The lamination processability is usually achieved at the temperature of the hot press rollers of the laminating machine at105℃±10℃, line pressure is0. 54kgf/ cmand the transmission speed is0. 9～1. 8m/ minThe dry film can be firmly applied on the substrate of copper foil under the condition of

(4) The spectral absorption region of photoresist in dry films with spectral properties at wavelengths310～420nmThe wavelength of the safe light region is greater than or equal to460nmThe high pressure mercury lamp and the halide lamp have higher radiation intensity in the near UV region. High-pressure mercury lamps and halide lamps have higher radiation intensity near the near-UV region, and most of the wavelengths are in the spectral absorption region of photoresist, which can be used as light sources for dry film exposure. Low-pressure sodium lamps mainly radiate energy in the wavelength of589. 0～589.6nmIt is a good monochromatic range, in line with the operating safety light of the dry film, and the yellow light emitted is more sensitive to the human eye, bright, and easy to operate.

(5) The light-sensitive properties of light-sensitive dry films include light-sensitive speed, exposure time tolerance and depth exposure.

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