Several methods for making plate negatives

Screen printing requires a set of printing plates, and the plates must be made to meet the requirements. Therefore, the preparation of the film can be said to be the first process of screen printing. According to the quality standards required for prints and the size and fineness of printed patterns, the following methods can be used separately.

First, hand-painting method

This method is generally applied to a relatively thick line, a relatively simple structure, and a large format. The most commonly used ink is depicted. The best choice of ink brand name products, characterized by moderate viscosity, strong adhesion, no precipitation, no cracks. It is also possible to use thicker advertising paints, oil paints, etc. that have a certain hiding power to paint, but their adhesion and solvent properties are different, and they can be flexibly selected according to the material of the film.
Materials that can be used as a film include glass, transparencies (such as slide films, transparencies, laser films, etc., which are generally available at stationery stores and computer consumables stores), sulfate paper (Tracing Paper), and polyester film (available at surveying and mapping supplies). .
Among the materials listed above, the most important polyester film is the most useful. It is very smooth on one side and has a matte surface like frosted glass on the other. This polyester film has the advantages of good light transmission, easy ink, no shrinkage, and not easily deformed (sulfuric acid paper is easy to meet the water deformation wrinkles). When handling, do not use your fingers to directly touch the hair, otherwise the sweat or oil on your hands will leave a fingerprint on it, and the convenience of fingerprints is not easy to ink. When the film is finished, a light transmission inspection is required. In areas where the ink is thin and where the coverage is poor, it is necessary to redraw the correction until the dark area is not translucent. The transparent area is free from dirt (if the stain is not carefully contaminated, it can be dirty. The dirt is scraped off with a blade.)

Second, manual engraving method

The scope of application of this method is similar to the manual drawing method, except that the lines of the pattern are required to be consecutive. Otherwise, the carved pattern will be scattered and difficult to locate the printing plate. Therefore, the pattern is scattered with the drawing method, the pattern is consistent with the knife carving method. There is no special requirement for the cutting knife, as long as you use it, you can use it smoothly and sharply. The choice of film material can be very large, as long as a certain degree of shading is achieved, such as thicker paper and cardboard. The edges of the film pattern produced by this method are neat, the lines are smooth and smooth, and the film produced by the drawing method is finer.

Third, the computer engraving method

The development of computers and related equipment has also provided many convenient conditions for the production of negatives, of which the computer cutting plotter is one of them. The computer cutting plotter can not only engrave a variety of fonts, but also can engrave some line patterns, and its engraving space can be from one to two centimeters to more than one meter square. The characters carved by the cutting plotter are usually instant sticky papers, and the characters or patterns carved can be directly printed on the screen, or they can be collaged on a piece of transparent paper or glass. Computer lettering service can be found in some decoration stores or computer service stores. However, in order to engrave more complicated patterns, the computer cutting plotter shall be required to be equipped with a corresponding scanning device, and the existing pattern scanned into the computer can be engraved.

Fourth, the copying method

The use of copiers to make negatives, the biggest advantage is that you can zoom in and out. If the original in the hand is not the same size as the one you are about to make, scaling with a copy machine is the easiest solution. When copying, you should find a copy machine with good contrast. You can use transparencies (slide film, transparencies, etc.) or sulfate paper for the film material. Transparencies can generally be copied directly. Sulfuric acid paper is thin because of the paper, copying may be prone to failure, you can use the following solution: the sulfuric acid paper tape with a copy paper, and then copy the sulfuric acid paper into the copier, can be like ordinary copy paper It was photocopied.

Five, laser printer method

Laser printers have become very popular and are the easiest way to create text negatives. It has replaced much of the traditional photographic method of plate making. Laser printers can not only produce a variety of font negatives, but also can produce a variety of line pattern negative film under the support of scanning equipment, and the production process can be freely arranged, arbitrarily modified, very convenient, and can be both positive and negative sheet. The produced negative film can also achieve higher accuracy. The film material can be a special film for laser printers, or it can be replaced with sulfuric acid paper.

Six, photo-making

Fine, complex patterns still require the use of industrial photographic methods to make negatives, especially tone films, which must be photographicly processed. Conditions can be self-photographic plate, can also commission a special plate-making center or a larger printing plant on behalf of the processing. To do the color tone printing, you need to electronic color separation of manuscripts, but also need special color separation equipment and technology can be completed, and its work is only large printing or platemaking center can bear.

Source: I love Hanchuan