Three aspects of the hottest self-adhesive label

All aspects of self-adhesive labels (III)

label printing of self-adhesive labels

at present, self-adhesive label printing in the world is basically divided into three situations:

1. The printing method based on flexo

North America, represented by the United States and Canada, is a typical representative of using flexo to print self-adhesive labels. Its equipment is a unit type printing unit, which mainly uses oil ink ink and adopts round pressing and die cutting. The processing method of materials is web printing and web receiving

2. Letterpress and flexography account for about 50% of the printing methods

this processing method is represented by Europe. The situation of flexography printing labels is the same as that of the United States, but letterpress printing accounts for a considerable proportion. Relief printing uses UV ink, and the equipment is mostly laminated or satellite. The processing method of materials is also roll printing and web receiving

3. The printing method based on letterpress

this processing method is represented by the Asia Pacific region. In the Asia Pacific region, there are many home furnishings in developing countries, and label printing is relatively backward. Only a few devices use UV ink in letterpress printing, and most label devices still use traditional resin ink. The processing method of materials is web paper,

now, let's introduce the specific printing and processing technology of paper self-adhesive labels:

1. Printing and processing process

different kinds of materials and labels for different purposes use different process flows. Generally, the label printing machine is a multi-function equipment, and the processing factory can formulate the printing process according to the requirements of customers. The process flow of self-adhesive label printing is as follows:

(1) unwinding

a intermittent type: there is no tension change when the web is unwinded, so it does not need to be adjusted. It is used in flat and round flattening label machines, and the unwinding speed is slow. Since such equipment has no paper positioning correction device, the end face of the web is required to be clean to ensure accurate overprint during printing

b continuous type: it is applied to the rotary label press. As the tension of the paper changes when the diameter and speed of the web change, this device has automatic or manual tension control. I hope it can bring you a help mechanism, as well as a web deviation correction device to ensure stable paper feeding and ensure the printing quality

(2) bronzing

flattening: it is applied to the circular flattening and flattening label machine with low speed

round pressing: it is applied to the round pressing label printing machine, which is fast and can be bronzed continuously. It is rarely used, and the gold printing process is widely used instead of bronzing

(3) printing

flattening: suitable for small-area, simple pattern printing, such as price labels, bar codes, etc

round flattening: it is suitable for label printing with field and general patterns, and can be used for simple color eye tone printing

round pressing is suitable for all kinds of pattern label printing, especially for high-grade color eye tone label printing

uv printing: in the above three printing methods, film adhesive materials can be printed after UV drying

(4) bronzing first and then printing

on equipment without UV drying, ordinary ink is used, but the disadvantage is that the design of printing pattern is limited. But

(5) printing first and then bronzing

it is applied to the equipment with UV drying device. The ink is quickly dried and then bronzed on the ink. The bronzing pattern is arbitrarily designed, which is not limited by the ink. It is suitable for the printing of high-grade labels. It is an advanced production process

(6) glazing

field glazing: apply a layer of varnish on the surface of the ink to protect the ink layer from moisture, water and improve the surface gloss. It can replace the lamination process and adopt UV drying method

(7) laminating

laminating on paper or film materials is to protect ink, waterproof and moisture-proof, increase label strength and increase the three-dimensional sense of patterns. Lamination is divided into backing paper lamination and backing paper lamination, which is widely used at present because of its low cost. According to the requirements of the process, there is a composite packaging machine 'target=_ Blank> there are two kinds of transparent film and matte film. The former is widely used

(8) punching

is not widely used and is mainly used for labels printed by computers. It is required to punch positioning driving holes on both sides of the label, or for the label applied on the price gun, it is required to punch holes in the middle of the label for positioning and driving

(9) die cutting

the die cutting of self-adhesive labels is a semi cutting process, that is, only the surface material is cut through and the bottom paper is retained. There are two processing methods that can complete the change of plunger position in a few seconds:

such as flat die cutting, which is suitable for all kinds of label printing machines. Manual plate making, with low cost, short plate making cycle, but low viscosity, is suitable for short plate printing processing. At present, almost all domestic label factories use flat die-cutting. The other is circular die-cutting, which is applied to circular pressing label equipment. It has fast speed and high die-cutting viscosity, and is suitable for long-term printing. The disadvantage is that the cost of plate making is large and the cycle is long. At present, the die-cutting rollers of domestic manufacturers are generally processed abroad

(10) paper receiving

can be roughly divided into cutting paper receiving and folding paper receiving

2. Processing methods of paper self-adhesive labels

(1) among the printing methods of sheet fed

self-adhesive materials, offset printing accounts for 95%, embossment printing accounts for 2%, silk screen printing accounts for 2%, and computer and printing accounts for 1%. The self-adhesive label printing of single sheet paper is the same as that of ordinary printed matter. Each process is completed on a single machine, which has low production efficiency, high consumption and high cost, but the printing quality is good. If the offset printing process is adopted, the quality of labels printed by four-color color printing is much better than that of similar products printed by label printing machine. However, since the self-adhesive finished product printed on sheet fed paper is in the form of sheet fed paper and cannot be rewound, this kind of product can only be labeled manually, and cannot be automatically labeled on the automatic labeling machine. Its influence on mechanical properties is discussed. Sheet fed printing is suitable for large-area self-adhesive color printing. Such as posters, posters, large-area labels, etc., are not limited to label products. It can be said that sheet fed self-adhesive printing is an important part of the self-adhesive printing industry

(2) web paper

among the printing methods of Web self-adhesive materials, embossing accounts for 97%, silk screen printing accounts for 1%, offset printing accounts for 1%, and flexo printing accounts for 1%. Due to the use of web printing processing, all processes are completed on one machine, so the production efficiency is high, the consumption is low, and the cost is low. At present, the label printing machine in China is in the form of relief printing, with few functions. It is only suitable for printing labels with simple color blocks and line patterns, and its printing quality is not as good as that of sheet fed offset printing labels. However, labels processed with web paper can be rewound into rolls, which can be applied to automatic labeling machines, bar code printers, electronic scales and other equipment for automatic production. Web printed self-adhesive labels are the mainstream of self-adhesive printing in the world