Why should the surface of printed matter be treated with varnish?
Who knows printing are no strangers to varnish. After we finish printing, we need to use varnish on the surface of the printed matter. What is the reason behind this? Next, a professional China printing company will introduce the characteristics of varnishing, which is colorless, odorless, strong gloss, fast drying, and chemical resistance.
1. Have a certain degree of flexibility
Any bright film formed on the surface of the printed matter must maintain good elasticity to conform to the flexibility of the paper or cardboard without causing cracks or cracks or shedding.
2. The film has high transparency and does not change color.
For decorative prints, depending on the surface of the printed sheet to form a colorless and transparent film, an excellent glazing effect is obtained, and the image does not change color after drying. Moreover, it will not change color or turn yellow due to the sun or long-term use.
3. Wide applicability of post-press processing
After glazing the printed matter, it usually needs to be processed by post-processing, such as: stamping processing, hot stamping and aluminum processing. therefore. The glazing film layer is required to have a wide range of applicability after printing. For example: good heat resistance, hot stamping of aluminum, no adhesion phenomenon; high solvent resistance, the dried film layer cannot be foamed, wrinkled or fluffed due to the influence of the adhesive in the post-processing. Sticky phenomenon.
4. The film layer has better environmental performance
Some printing materials behind the glass are used to make various types of packaging cartons. In order to provide good protection for packaging products, it must have good environmental resistance of the glazed film. For example, the packaging of food, cigarettes, cosmetics, clothes, etc. must be moisture-proof and mildew-proof. In addition, the chemical properties of the film should be stable after drying. By contacting chemical substances such as weak acids or weak bases in the environment, the performance cannot be changed.
5. There is a certain degree of adhesion to the surface of the printed matter
Due to the influence of the integral density value of the ink layer on the surface, the surface viscosity is greatly reduced. In order to prevent the film from drying and peeling during use, film adhesion is required, and various types of inks and inks are used. The auxiliary materials have certain adhesion.
6. The film has a certain degree of wear resistance
Some glass prints require a certain degree of abrasion resistance and scratch resistance after glazing. Due to the high-speed cartoning machine, carton packaging machine, book cover and other assembly lines in the production process, the surface of the printed matter is rubbed, so it must have abrasion resistance.
7. Good leveling, smooth paint film surface
Various printing materials, combined with the influence of printed graphics, surface absorbency, smoothness, wettability, etc., in order to make the glaze coating form a smooth film on the surface of different products, a varnish is required. The leveling performance is good, and the film surface is smooth after film formation.