| The thesis's purpose is to study on the technologic parameters of color halftone screen printing, obtain the optimized value of technologic parameters, ensure the consistency between printed matter and manuscript, provide theory and experimental basis for implementing datumization and standardization. It's beneficial to standard process flow of enterprise and it can enhance the quality of printed matter, reduce the production cost, and increase economic benefit.The main parameters were studied according to screen printing technology principles combining with the control strip and the halftone screen printing test target; studying moirédistribution law by geometrical optics and bonding the principle of space visual compounding to choose dot/line and screen parameters. The dot gain and dot compensation models were established based on experimental result.The test target of the color halftone screen printing technologic parameters was designed. The right emulsion exposure parameter was obtained and relational expression of screen printing resolution was verified. The curves of dot gain, printing gradation and dot compensation under different screen frequency were established. The dot/line relational expression was verified by experiment and the rational dot/line ratio was defined.The conclusions: The color of emulsion is changed from yellow green to grey green by different exposure time, so, the exposure time can be judged by the color of emulsion. The relationship between resolution and mesh indicates that higher mesh counts and thinner mesh diameter is better for reproduction. The phenomenon of dot gain and moiréis more serious because of higher screen frequency, so that, the value should be the less the better in screen printing. When dot/line below 3.5, the screen angles in screen printing should be 4 to 8 degree different from lithographic printing's screen angle; Reasonable dot/line value is defined by the scope of gradation, range from 3.5 to 4.7.
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