Plate Making Quiz

Q: What are the meanings of “screening”, “screen”, and “net point” in screen printing books? What does “screen printing” play?

A: The commonly used screen printing plates are screen printing texts, line patterns and color block graphics. The number of such screen printing plates is the largest, accounting for the vast majority of the screen printing volume; the other type is screen printing color images, and the screen consists of Composed of printed ideas, it can reproduce the shades of color in a color photograph or artwork, and can express the color of the original image gradually and gradually. It can not be expressed by lines, but rely on screen printing plate to reproduce the original. This is the role of "screen printing plate" in screen printing.

"Covering" is the abbreviation for making screen printing plates. It includes a screened image on the original (master) and a screened image on the plate. "Screen" is a tool for forming dot images during the manuscript creation process. "Network" is the printing idea printed on the substrate, ie, the smallest unit of the screen image. There are two types of screening: one is the traditional dot-screen image produced by the screen. The dots of this type of image are of different sizes, but each dot has a fixed position, between the dot and the dot. The distance is also fixed, forming a neat network structure, that is, the amplitude of the network; the other forms of the image of the same size, the position of the points are scattered, the number of points in the unit area is different, the number of points gathered A much more area is a dark-colored section, and a less-proportioned area is a light-colored section. This kind of idea is irregularly distributed and there is no "net-like structure". This method of screening is FM screening and is currently applied less frequently.
The "net" mentioned here has nothing to do with the "net" of the screen.

Q: I am a beginner who is new to screen printing technology. I feel that it is difficult to choose the printing materials. Is there any way to see a certain type of printing materials and select certain types of printing materials?

A: This is indeed a problem that is quite difficult and very interesting. If there is a person who “sees (printing) material (printing material)”, then he must be a screen printing expert or a “master” level figure, and I am not able to answer it satisfactorily. However, there are questions and answers must be answered, even if the answer is not very satisfactory. Generally speaking, the printing material is selected according to the surface properties of the printing material. The basic conditions are: 1. Strong binding force; 2. Drying time of the printing material adhered to the printing material, within the allowable time of the process For example, printing and drying are the most ideal. Drying in one or two hours is not bad. Even if it is fully dried in the next day, it can be accepted in practice. However, if you want to dry two or three days, I am afraid we must delay the delivery time; 3. Substrate surface hue, does not affect the reflect the hue and gloss of the printed material (or matt requirements). There are special requirements of the print, such as resistance to stamping, pickling, printing and easy to fall off the protective layer and other properties. From the screen printing material market supply situation, almost every kind of printing material has its corresponding printing material. As a screen printing worker, we must first understand the type of printing materials, such as paper, plastic, metal, glass, wood, Fabrics, etc., At the same time, understand the common inks, plastic inks, paints, colorants, and plastic type printing materials that are suitable for printing with these materials. Where do you know? You can learn a lot of knowledge, including the method of selecting printed materials, through screen printing technology training courses, reading screen printing publications, visiting exhibitions related to screen printing, and sharing information with friends engaged in screen printing. Another important measure is to create conditions for field operations and to accumulate experience. It will take a long time to get through. In the end, I used the "practice to know the truth" and my friends at Beginner Screen Printing to share it.

Q: During the process of making screen printing plates, it was found that the development was very difficult. The shape of the images can be seen on the layout, but the mesh that constitutes the image is not transparent and is still sealed by the photosensitive film. How does it work to prove that it is photosensitive? Latex expired?

A: In the normal exposure time, the screen cleaning operation is correct, and other conditions have not changed under the premise of the above-mentioned phenomenon, often due to photosensitive adhesive expired. The following operations were used to prove that the photosensitive adhesive was expired: The photosensitive adhesive was applied on a clean blank screen plate according to the normal operation, and after drying, the developing operation was performed without exposure, and the result was judged from the status of the layout.
The film on the layout is washed with clean water and there is no residual film, and the original appearance of the screen after cleaning is restored. This is a normal photosensitive adhesive and can be used continuously; the film of the layout is partially dissolved, washed away with water, but the wire The mesh of the net is still firmly sealed by a thin layer of film. This condition indicates that the photosensitive adhesive has expired and cannot be reused.

Q: What is a capillary film?

A: A kind of photosensitive film used in screen printing plate, this film is applied to the film base (commonly used polyester film), this type of film is called capillary film, and some people also called "film" according to the transliteration. Capillarity means a photosensitive film with capillary action. Capillarity manifests itself in the process of film production. When the photosensitive film encounters a wet screen, a capillary phenomenon occurs between the slightly soluble film and the mesh, that is, the sol and the mesh are closely combined, and the glue is absorbed around the mesh. Enclose the mesh, so that the film and the mesh are more firmly bonded. The "capillary photosensitive film" is a photosensitive film having a capillary action.





Author: Zhu Shen Xiang Source: Screen Printing