A Brief Analysis of the Characteristics of Mesh Stretching Applied to Screen Printing

[ppzhan Abstract] Screen stretching is an indispensable process in making screen printing plates. Screen stretching is to firmly fix the screen mesh on the screen frame under a certain tension, and to make the stretched screen mesh have a certain tension, so as to meet the requirements of photosensitive agent coating and other plate-making requirements. It is mainly used in the screen printing industry and the printing industry. Screen stretching includes manual screen stretching, mechanical screen stretching, and pneumatic screen stretching, etc.

The level of screen mesh tension and the quality of screen stretching are directly related to the quality of the screen printing plate, and also have a direct impact on printing quality. In color printing, it is required that the screen tension of each color plate of the multicolor screen printing plates be kept basically consistent, so as to ensure accurate registration. Only when the screen is well stretched can plate-making and printing quality be guaranteed. Screen stretching mainly includes two methods: manual screen stretching and mechanical screen stretching. Manual screen stretching is a simple and convenient traditional method. It is usually suitable for wooden screen frames. This method fixes the screen mesh on the wooden frame manually using materials such as nails, wooden strips, and adhesives. The tension of manual screen stretching can generally meet the requirements, but the tension is not uniform, the operation is rather troublesome and time-consuming, and the stretching quality is not easy to guarantee. This method is mostly used for small-volume printing and occasions where printing precision requirements are not high.

Mechanical screen stretching uses mechanical force to tighten the screen mesh and firmly bond it to the screen frame with adhesive. After the adhesive dries, remove the screen frame and seal the edges with polyester film single-sided pressure-sensitive adhesive tape, so as to prevent the adhesive from dissolving and to keep the appearance of the screen printing plate neat. Screen frames of various materials can be used with mechanical screen stretching. Mechanical screen stretching has the characteristics of uniform tension and short stretching time. It is easy to master the required tension. It is suitable for plate making with high precision requirements.

The quality of screen stretching is directly related to the quality of screen printed products, such as registration accuracy, image clarity, uniformity of the ink layer, and the jagged edges of line art and the degree of moire of images. Therefore, it can be said that screen stretching is an important link in screen printing. Because manual screen stretching is rather troublesome, time-consuming, and hard to guarantee in quality, it is used only in cases of small-volume printing and low precision requirements. At present, the most widely used are pneumatic and mechanical screen stretching, but dedicated screen stretching machinery must be provided.

——This article is reprinted from China Packaging Network (pack.cn). Original link: http://news.pack.cn/show-361789.html