Key points in the selection of raw materials for aluminum-clad packaging and process control
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
The aluminum-washed composite packaging film product has a bright pattern, high transparency at the window opening, excellent shelf display effect, and can be adapted to high-grade packaging of various contents, and has a great development space in the field of high-end composite flexible packaging. This paper summarizes the selection elements of the aluminum-clad packaging raw materials and their key process control elements.
First, the choice of raw materials related to aluminum packaging
When companies need to develop aluminum-washed packaging, they must first choose high-temperature varnish and water-solvent varnish.
1, the choice of high temperature varnish
During the printing process, the high temperature varnish is applied to the ink on the printing area and is plated on the surface of the varnish. Therefore, the following requirements need to be met:
1) no reaction with the color ink, does not dissolve the color ink.
2) The temperature in the aluminum plating process is very high, so the varnish should have a good high temperature resistance effect, and can effectively protect the printing ink from being corroded by aluminum vapor during the evaporation process.
3) strong adhesion with ink, and aluminum layer also has good adhesion, to ensure good appearance after washing aluminum.
2, the choice of water-soluble varnish
The water-soluble varnish is applied to the blank of the non-printing area, and it needs to be washed away with the aluminum layer attached thereto during the aluminum washing process. Therefore, the following requirements need to be met:
1) It is fully and densely combined with the film itself, and there are no problems such as uncovered dots or particle lines.
2) Good water solubility, can be quickly and completely peeled off from the film when exposed to water.
3) The varnish has good leveling and easy to coat evenly.
4) Determination of the number of varnishes and the parameters of the net depth: the number of net lines and the depth of the net are the main parameters of the mesh roll. If the net is shallow, when the varnish is applied, the varnish is insufficient, and when the aluminum is plated, the effect on the high temperature is not good, and the printed pattern is affected. If it is too deep, it will cause the cost to be too high, and it will easily cause the problem of uneven thickness of the glazing oil.
Second, the key process control of aluminum washing packaging
In the production of aluminum-washed packaging, it often encounters inaccurate color registration, insufficient cleanliness of varnish, resulting in varnish knife; high residual solvent; washing and washing is not clean. If these quality problems are not discovered in time, they will not be discovered until the subsequent process, and the production losses will be even greater. Therefore, it is necessary to particularly strengthen the key point control of the aluminum washing printing, and reduce the quality loss caused by the printing process.
1, overprint accuracy guarantee
At the time of printing, in addition to the transparent inks of the respective colors required for the normal pattern, it is also necessary to print a layer of high-temperature resistant varnish at the position of the pattern, and uniformly deposit a layer of water-soluble varnish in the blank area. Therefore, it is necessary to strengthen the color monitoring and control of ink, high temperature varnish, and water-soluble varnish.
2, high temperature varnish quality control
1) The ratio of varnish to oil is accurate, otherwise it is easy to produce poor ink, and the ink layer is destroyed after aluminum plating;
2) Matching time of varnish and oil, and then configure after being proofed during production. This process requires special personnel to configure, otherwise it will easily lead to glue curing;
3) Clean control of varnish. Before printing, filter mesh should be used to filter high temperature varnish to reduce the problem of varnish.
3, water-soluble varnish control
1) The water-soluble varnish is poorly inked, resulting in penetration of the aluminum layer;
2) Drying of water-soluble varnish, try to use original ink to print;
3) Cleanliness control of water-soluble varnish. Before printing, it is necessary to filter the water-soluble varnish with a filter to reduce the problem of knife and plate printing.
4, residual solvent control
It is necessary to control the residual solvent, otherwise it will directly affect the degree of vacuum.
5, printing roller control
1) Use a new rubber wheel to ensure even ink on the varnish and washing ink;
2) Check the quality of the ink transfer roller to ensure uniform ink transfer.
6, scraper control
Scraper control: Reduces the occurrence of chipping and poor inking caused by scraper wear, using a ceramic scraper.