Application of special gloss pigments in packaging printing
We are a big printing company in Shenzhen China . We offer all book publications, hardcover book printing, papercover book printing, hardcover notebook, sprial book printing, saddle stiching book printing, booklet printing,packaging box, calendars, all kinds of PVC, product brochures, notes, Children's book, stickers, all kinds of special paper color printing products, game cardand so on.
For more information please visit
http://www.joyful-printing.com. ENG only
http://www.joyful-printing.net
http://www.joyful-printing.org
email: info@joyful-printing.net
For many print users, special gloss pigments are a relatively unfamiliar concept, but if you talk about pearlescent pigments and pearlescent effects, the printing industry is much more familiar, such as the Merck series. The traditional "pearl pigment" has a very limited semantics, and it is easy to make people think that the effect of this pigment is like pearl: white, translucent, soft and elegant. In fact, even if there are many variations in the series, such as S-grade (10~100μm) pigments, the particles are relatively thick, and the texture is exactly the same as the soft-gloss pearl. For example, 300 and 500 series of iron oxide pigments, the performance is that there is no metallic luster in the pearl.
Therefore, for such layered structures, products that exhibit gloss on the principle of refraction/interference are more accurately or representatively represented by "special gloss pigments".
At present, in the domestic packaging field, the application of special gloss pigments is more and more common, not only in the unique gloss effect, but also because it is simple, flexible, economical and environmentally friendly. For the packaging of most high-end consumer goods, such as cigarettes, alcohol, candy and cosmetics, this decoration is more reasonable.
The following is a new procedure that the author tests on special gloss pigments in packaging and printing for reference.
First, Sheet paper gravure printing process
It is customary for most users to use the method of engraving gravure printing because the particle size of the pigment is relatively large, and it is necessary to use a large ink transfer method to transfer a certain amount of pigment to the packaging material, so that the printing achieves an ideal gloss effect. .
However, in the paper making process, the traditional gravure printing cost is high, the main reasons are: First, the printing plate printing cost is high; Second, the roll paper feeding method wastes a large amount. On the other hand, the cost pressure of packaging customers is getting bigger and bigger, and the packaging style changes rapidly, and the short version work is more and more. In this way, printers have to adopt a workaround, such as sheetfed gravure is an effective solution.
Sheet-fed gravure can be combined with offset printing. Uncolored gravure pigments can be offset, which greatly reduces the cost and wastes paper much less, but for special glossy pigments with large flaky particles. A gravure plate can be used to form an effective ink layer thickness to achieve a satisfactory effect.
Special gloss inks are used as a base color in the packaging design. Making a solid plate cylinder can cope with the use of different special gloss inks on multiple jobs, thus saving a lot of money from the printing plate.
Another advantage is that it can be used for printing proofs, wasteful, and the effect is basically the same as the product. It is very effective for the pearly special gloss proofs and is more conducive to packaging customer communication.
However, it should be noted that the printing speed and printing pressure of the single-sheet gravure are somewhat different from those of the conventional web gravure. Sometimes it is necessary to adjust the performance of the ink to ensure the effect.
Second, offset printing online / offline glazing process
If you do not use sheetfed gravure, another method that can be combined with offset printing using a special gloss effect is glazing. Glazing, also known as "over-oil" or "covering", is traditionally a type of post-printing process that protects the ink layer from smudging, bruising, and provides additional shine. Said to be "glazing", in fact, the use of the process "printing", the transfer of special glossy ink, because the offset printing ink layer is very thin, can not form a good gloss effect, so this is a kind of "decorative glazing ".
Such glazing can be arranged after other ink colors are printed as needed, or can be arranged before use as a primer.
There are several ways of glazing in packaging and printing. The author suggests using water-based or solvent-based glazing of a special glazing mechanism instead of using the printing unit “offset varnish” in offset printing, which is too viscous. Moreover, the transfer property of large particle pigments is poor.
In recent years, the glazing development equipment uses a "closed scraper type" mechanism to transfer varnish through an anilox roll or a photosensitive resin plate. In addition to saving the amount of varnish, this mechanism has the greatest advantage of being able to perform proficient partial glazing and unique decorative effects. This is very important for the application of special glossy materials. In fact, it is also a flexographic printing unit. Here, the anilox roller has a great influence on the transferability of the pigment. The too small number of mesh lines cannot guarantee effective transmission, and it is too thick and causes drying problems.
The old-fashioned "double roll" mechanism can also be used for the construction of special glossy pigments, but it is not possible to perform precise local glazing. If you use water-based glazing, you must pay attention to the drying problem. On the one hand, the water-based varnish is relatively slow to dry. If you want to increase the printing speed, you must adjust the gloss parameters. On the other hand, if the water-based varnish is difficult to remove on the plate roll, it will stop. For a little longer time, the plate roller must be carefully cleaned first. Considering that customers can use them in different ink systems, different pearl pigments were produced for water, solvent and curability, respectively, and the abbreviations W, S and UV are respectively indicated in the pigment names.