GB/T 38153.3-2019 is Part 3 of the series of standards for "Graphic technology — Laboratory preparation of test prints," specifically addressing screen (porous) printing inks. This standard provides a comprehensive, unified, and standardized methodology for preparing screen ink test prints in the laboratory for performance evaluation. Its core purpose is to assess various key properties of inks and substrates through these standardized prints, including optical characteristics such as colorimetry, transparency, and optical reflection density as described in ISO 2846-4, as well as gloss, lightfastness, and resistance to chemical, physical, and mechanical factors. During the preparation of such test prints, screen printing proofing machines (such as those equipped with squeegees and flood coaters with controllable pressure) are typically used to ensure the uniformity and consistency of the prints. Subsequent performance evaluations are carried out using relevant testing instruments such as reflection densitometers (for measuring optical density), spectrophotometers (for color and transparency measurements), and gloss meters.