Aluminum foil was so printed!
Aluminum foil is a very popular packaging material.
Features: non-toxic, with excellent thermal conductivity and shading performance; moisture, airtight, fresh.
In the field of modern printing, aluminum foil products as printed materials are:
Aluminum foil, aluminum foil composite materials, aluminum materials.
Aluminum foil composite material is the most common aluminum foil. Today, Xiaohui for everyone to introduce is the aluminum foil printing process.
Aluminum foil is a high-grade packaging paper, it can replace a large area of Dian Hualv hot stamping, product color, not only improve the grade of the product, but also improve the value-added products, widely used in high-end merchandise trademarks and packaging.
Aluminized paper in some developed countries has been as a new environmentally friendly materials, widely used in product packaging, in the country has become a development trend.
1. The structure of aluminum foil
Composite aluminum foil mainly by the paper (aluminum foil backing), aluminum foil, coating and other components.
Aluminum foil backing paper is a high demand for processing paper, the quantitative range of 21 ~ 50 g / m2.
2. Aluminum foil performance
First: with a smoother surface, is not conducive to the transfer and absorption of ink.
Aluminum foil layer structure is tight, the surface almost no gap, do not have the paper as the absorption and permeability. Therefore, the contact material, solvent and moisture in the ink layer after printing can not be absorbed and remain on the surface of the aluminum foil, which affects the initial drying speed of the ink layer, resulting in imprinting stickiness.
Second, the aluminum foil due to the surface of the aluminum foil layer and the density between the density, strength and stability of the physical properties of the larger difference between the two properties of different materials together, the expansion rate is inconsistent, vulnerable to ambient temperature and humidity Affect the occurrence of curl.
When the ambient air moisture content is greater than the moisture content in the backing paper, the liner absorbs and elongates, aluminum foil to the foil curl;
When the water content in the ambient air is less than the moisture content in the backing sheet, the backing paper is dehydrated and contracted, and the aluminum foil is curled toward the backing sheet.
3. Requirements for prepress design
First: the use of ordinary ink printed on aluminum foil, the imprint on the color of non-metallic or metallic luster.
Natural (silver) aluminum foil + transparent yellow ink presents gold
To Yinban version of the way printing, not only can get metal shiny graphics, but also with a variety of color graphic composition of the screen.
Second: the ink with different transparency were printed, can get different degrees of imprinting gloss.
Silver foil + white ink is better
But the golden aluminum foil + white ink is khaki
Design should be based on the characteristics of aluminum foil, the different shiny applied to the same screen, will get a unique artistic reproduction effect.
Third: If there are four-color overlay network images, should be designed for a small area, should not use a large area of four-color overprint.
Beause aluminum foil paper absorption performance is poor, ink drying slow. Should be used in a variety of spot color printing, both simple and can make India after the pattern is more saturated, the effect is better.
In short, the design of printed on the aluminum foil, aluminum foil and its printing technology should understand some of the characteristics of the full use of the characteristics of aluminum foil itself, as far as possible reflects the metallic luster.
Design patterns should not use a large block hood strong hue, or neither reflect the aluminum foil metallic luster, but also a lot of consumption of ink.
Design of color with a transparent ink on the aluminum foil for monochrome or color printing, should avoid more than three times ink printing.
4. Aluminum foil printing process
1, printing methods
Aluminum foil printing requirements are relatively high, can be offset, gravure, flexographic printing.
Gravure printing: suitable for printing large quantities of roll material. The surface of the impression cylinder is wrapped with a layer of elastic blanket with a certain elasticity so that the ink at the pits is smoothly transferred to the surface of the aluminum foil.
Flexible printing: more advantages than gravure, plate speed, low cost, high efficiency, not only for large quantities of printed copies, the bulk of small, more varieties of printed the same applies to be promoted.
Offset: Because of its easy plate making, network clear, printing speed.
2, printing color arrangement
Aluminum foil on the color printing, the foil foil foil itself has a color, in order to ensure the correct reduction of ink hue, pre-printed must be printed background.
Can not cover the color of the foil to live, so that the white ink on the more colorful ink;
The polar groups of white ink can be used to increase the adsorption capacity of the surface.
If the earth version of the overprint, should be shallow after the deep;
Anatomical version of the color printing, ink should be covered with a large print;
Small area of text or line version should be printed, such as text version, bar code, the main color after the Indian;
Registration accuracy requires a high color should be printed (because aluminum foil paper both the physical properties of metal, but also the physical properties of paper, the first printed because the paper deformation is small, easy registration).
Method of arrangement:
① white, yellow (opaque), magenta, blue, black;
② white, yellow (opaque), black, magenta, green;
③ white, yellow (opaque), black, blue, magenta;
④ white, yellow (opaque), green, black, magenta