Application of Color Screen Printing Technology in Lightbox Advertisement

In the production of lightbox advertisements, in pursuit of realism and artistry, color reversal magnification films or photo inkjet printing are used, which has the characteristics of high production cost, poor weather resistance, and poor reproducibility. Therefore, its popularity and durability are worse than other advertisements.

For this reason, light box advertisements are currently being made on special papers and plastic films by screen printing methods, so that problems such as cost and weather resistance are solved. This article talks about the application of color screen printing technology in terms of the characteristics of print advertisements and the requirements for common tone printing.

I. Advertising's "visual communication elements"

"Illustration" is the theme and center of advertising. "Photo priority, illustration first", whether it is photos or illustrations, the image is expensive, typical, real, moving and has a strong appeal to consumers. The “illustrations” of advertisements are mainly photography and painting, and all belong to advertisement information. Advertising information can be divided into three types: visual, auditory, and audiovisual. Print ads belong to the visual category, and 70% of human information is obtained from the visual. Advertising media such as newspapers, magazines, publicity cards, posters, road signs, calendars, and packaging papers are basically consistent in their visual communication materials—graphics, manuscripts, and colors. These materials are called visual communication elements. ".

The three major elements that make up "visual communication elements" are:

1. Graphical visual communication elements;

2. Document visual communication elements;

3. Color visual communication elements.

Second, the characteristics of "color visual communication elements" of advertising

"Color" separation and color two meanings. Color, including black, white, gray, or "no color." Color, including red, orange, yellow, green, blue, blue, purple, and mixed with black, white, gray of the intermediate colors, or "color." "Achromatic" and "colored" together, collectively referred to as "color."

People's evaluation of Guangyin is like the packaging of products, first of all with the above colors winning or not, and the quality of the product is the second. Color has become the primary condition for market information and product competition, so it has special appeal in print advertising. For example, there was a comparison of a black and white picture with a color picture for a cosmetic advertisement. As a result of research on “attention effect”, the result was that people paid attention to 46% of products on black and white pictures, and attention was paid to the products on color pictures. %, color is about 2 times better than black and white.

The colors on print ads, called design colors, are similar to those of painters in terms of color, but their purposes are very different. The painter can play as he likes, and the advertising color will be constrained by various factors such as product, cost, market, advertiser, consumer, printing, and paper.

Third, the main features and uses of screen printing

Printing is a highly specialized technique for copying originals. The vocabulary printed in the printing industry is actually the collective name for making plates, printing, and binding.

Modern print advertising consists of three elements: color, graphics, and manuscripts. Both graphics and manuscripts are inseparable from the expression of color. In contrast, color is superior to graphics and documents in visual communication. Whether or not the three elements can truly reproduce the intentions of the advertising designer and achieve the best effect of visual communication is achieved through various printing methods. Screen printing has features that other printing methods do not have. which is:

1. The printing ink is very pragmatic;

2. Can use a variety of ink printing;

3. Printing pressure is very small;

4. The layout is soft;

5. There is no limit to the shape and size of the substrate.

Therefore, screen printing can be performed in the case where printing using letterpress, lithographic, or gravure printing is very difficult or impossible, so its use is very extensive. For example: various outdoor signs, billboards, road signs, various decoration items related to commercial art, and various industrial-related electronic circuit boards, aluminum plates, instrument panels, thick film integrated circuits, and touch switch panels, etc. Products can be made by screen printing. In addition, due to its bright color effect and excellent light resistance, silk screen prints are suitable for printing long-term outdoor advertising and expressive and eye-catching posters and posters. At the same time, because of the thickness of the screen printing ink layer and the advantages of using various inks, it is very suitable for printing products with high visual effect requirements.

Fourth, the production of halftone screen points

Color or black-and-white manuscripts with shades of tones that need color separation and screening to achieve color and shade reproduction. Different from other printing methods, screen printing separation and screening have certain requirements and conditions.

For example, screen printing is difficult to reproduce over 100 lines/inch of screen dots. Therefore, 55 line/inch, 60 line/inch, and 80 line/inch magenta contact screens are often used. If you use a thin line like 150 lines/inch to touch the screen, you can make the negative film magnify 2 to 3 times and make a 75 line/inch screen feature as the original. In addition, when the monochrome screen is 45°, the mesh angle should be staggered when the two colors are used, so as to avoid moire after development. In the case of four-color printing, the red, blue, and black meshes are staggered at an angle of 30°, and the insignificant yellow is in between. Boxed screens and mesh negatives also produce moire, and the number of holes in the screen should be higher than 4 times that of the image screen in order to prevent this malady.

Table 1 shows the relationship among the layout, the observation distance, the number of screen dots, and the number of screen meshes:

(a) The original system:

1. The photo or artwork pattern adopts electronic color separation or photographic color separation technology to produce the halftone original in proportion (the number of screen lines is 50 to 80 lines/inch for hanging nets), and the yellow, blue, green, and black colors are positive. positive.

2. The text of the text shall be produced by phototypesetting or hand-painted black-and-white draft photography.

3. The manuscripts and designs are typeset according to the platemaking requirements and become the original version for printing.

(b) Network edition:

1. Select the screen size and mesh number according to the screen number of the original pattern.

2. Prepare the number of mesh frames according to the requirements for overprinting:

Monochrome printing: 1 frame

Two-color printing: 2 frames

Tri-color printing: 3 frames

Four-color printing: 4 frames

The tense force of each frame is measured with a tension gauge and is basically the same.

3. Photosensitive adhesive coating thickness should be uniform, the thickness is generally 8-10μm.

4. When printing, it is necessary to grasp the screen line and the screen latitude and longitude lines have a certain angle, generally 30 ° ~ 45 °, to avoid the appearance of moire after development.

Fifth, printing materials and printability, durability

1. Printing materials:

Choose a special printing paper that is similar to coated paper and translucent, or use a sand, semi-transparent plastic film or plastic base of PE, PP, or PC.

2. Ink:

The difference from general printing ink is that under the irradiation of transmitted light, the screen halftone print should produce a similar effect of the reversal film. Whether transparent ink can be used after being tested can be determined. In addition, different printing materials should be selected for different printing applications (for transparent printing materials).

3. Printability:

The printability should consider the following points:

(1) Printability;

(2) Printing effect.

4. Durability:

Durability should consider the following points:

(1) Hue and gloss retention

(2) Lightfastness;

(3) weather resistance;

(4) physical strength;

(5) secondary processing;

(6) Toxicity and others.