How to integrate packaging design with printing

Packaging and decorating design is a multidisciplinary discipline integrating packaging materials and printing technology. To achieve good results, designers need to be familiar with various aspects such as printing plate making process, printing process, and printing and packaging materials. In actual production, there are often cases where design effects that the designer wants to exhibit cannot be reproduced. This article combines the common printing methods to talk about the relationship between packaging and decorating design and printing.

1 Flexo printing

1) In the color design should be as simple, bright, bright, reduce the overprint of the design, and more use of spot colors to make up for the lack of four-color printing.

2) The increase in flexo dots is more serious than that of both plain and gravure, and there are also difficulties in contrast processing. In the layout design, large color blocks, small texts, fine meshes, etc. should be avoided in the same layout, even if the same color is divided into two versions. Due to the increase of flexographic dots, highlights can only reproduce 8% to 10% of dots. In addition, the gradient of color should be avoided to "0" in the packaging design.
3) Excessively fine text and line flexo printing cannot be printed, especially against white characters, which should be avoided when designing.

4) Flexo printing with gold and silver printing is rather dark.

5) Pay attention to two points when separating colors. First of all, the color separation line angle should avoid the network line angle of the anilox roller. The four-color screen line angle adopted by the flexographic plate is 7.5°, 37.5°, 67.5°, and 82.5° in order to avoid moire. Second, we must consider the number of screen lines and the number of lines of the anilox roller (1:4 to 1:6).
2 lithography

1) The number of screen lines:

Newspaper printing 80 ~ 100lpi;
General mid-range products 150 ~ 175lpi;
High-grade album 200lpi.

2) Consider the largest area that can be printed by a common printer and the size of a commonly used copy. Take into account the size of the paper, the size of the mouthpiece, the size of the bleeding, and the position of the control strip.

3) The same tone-based picture is placed on the same page as much as possible to facilitate the adjustment of ink color.

4) It is necessary to take into account the requirements for the post-press processing of die-cutting, stamping, foil stamping, film coating, and ticket numbering. For example, in the printing of tickets for some tourist attractions, we must pay attention to the number of links, to take into account the relationship between the size of the printer and the size of the ticket, the arrangement of the number in the face of the ticket and whether to play double number and other issues.

3 Gravure printing

Gravure printing rich color, strong color reproduction, high print rate. Can print on web, plastic film, metal foil and other substrates, but the plate making and printing costs are high, the plate making process is more complicated, and small batch prints are not suitable.

1) Minimize the use of over-printing lines that are too thin and too miscellaneous to avoid the font size being too small. In order to avoid overprinting and inaccurate lines caused by text, text aliasing.

2) Small text should be monochrome, and it should not use multi-colored cutouts, and it should avoid using the background of images (photos) to hollow out directly.

3) Spot color patches should be used as far as possible for shades that are not shaded.

4) Gold and silver printing should be used to make hollowed-out version. If lines and characters are printed in gold and silver, they should not be too fine or too small to avoid the ill-effects of writing and sticking.

5) Familiar with the performance of printing materials and printing methods. The color sequence in India is deep and shallow first, generally K, C, M, Y, and W. The color sequence of the table print is shallow and deep, generally W, Y, M, C, and K.

6) The circumferential length of the plate cylinder must have a positive increment in plate making. Such as OPP (unidirectionally-stretched polypropylene), PET (polyester) should have 0.02 ~ 0.03mm addition and release, and PE (polyethylene) about 0.05mm addition and release.

4 Screen printing

Screen printing and flat, convex, concave and other printing methods, there are many special places, mainly for the printing adaptability, thick ink layer, a strong sense of three-dimensional, strong adaptability to the ink.
1) It should be noted that the reproduction range of screen printing is small, generally 20 to 80%, small outlets are easily lost, and large outlets are easy to expand and paste.

2) Should pay attention to the relationship between screen and tone. Try to use high mesh screen printing.

3) Should pay attention to the relationship between ink and tone. Using UV ink, flat screen printing.

4) Due to the thick ink layer of the screen printing and the serious dot expansion, the thickness of the ink layer can be appropriately reduced. The GCR process can be used in color separation and plate making to reduce the ink volume of the three primary colors and reduce the dot gain value. It can also reduce the thickness of the photosensitive film and increase the viscosity of the ink.

5 Bar Code Design

1) In the design and printing, colors and images can be artistically processed, and bar codes cannot be handled arbitrarily. They must be operated in strict accordance with national standards (GB12904-1998). The magnification and reduction ratio of the product barcode can be changed within the basic size range of 0.8 to 2.0 times.

2) The line direction of the bar code should be consistent with the printing direction. The maximum circle diameter of the stain should be less than 0.4 times the standard width of the bar code strip.

3) The bigger the contrast between the bars of the bar code and the empty color, the better. Generally speaking, white is the background color and black is the bar color. The bar color of the bar code should be dark, and the light color should be light color. Since the reading beam of the barcode reading device is a red light having a wavelength of 633 nm, care is taken to avoid the red stripe color.

4) The position of the bar code should ensure that the symbol is not deformed and easy to read and operate. In the product packaging with curved surfaces, the bar code symbol shall be perpendicular to the surface bus bar. When the bar code is parallel to the printing direction and parallel to the bus bar, the curvature of the surface of the bar code symbol shall not exceed 30%. If the package diameter is too small, the bar code symbol shall be Rotate by 90°.

5) When designing the plastic film packaging bag, care should be taken not to design the bar code directly on the transparent film, and the backing color must be designed.

In short, to improve the level of design, packaging and decorating design must be combined with the printing process, and the designers of the decoration must be familiar with the professional knowledge of the printing plate making process, printing process, printing materials, etc., so that the originals designed can have good printing effects.