Plastic film gravure water-based ink

At present, domestic plastic gravure inks are mainly based on solvent-based inks, and low-solvent residue alcohol-soluble plastic gravure inks are gradually being promoted. However, the cooperating performance of gravure printing machines and the quality of printed products need to be improved. The ink has just been put into use. Plastic film gravure water-based ink is an environment-friendly liquid ink made of water as a solvent. Non-flammable, non-explosive, non-toxic, non-irritant, stable ink, bright color, high gloss, non-corrosive printing plate, easy to operate, low printing cost, good post-print adhesion, strong water resistance, fast drying, etc. .

Water-based inks, because they do not contain volatile solvent, improve the working environment, completely eliminate toxic and harmful substances in solvent-based inks, and eliminate the contamination of packaged goods. It is mainly used for rotogravure printing machine in PE, PP, PET, PVC and other thin-film printing food bags processed by EDM, shopping bags, milk packaging bags, medicine packaging bags, sausage bags, candy bags, beverage bags, children Toy packaging bags and other packaging printing products. Adapt to print speed 20-100 meters / min.

According to relevant reports, the CNCA will implement food product packaging products such as food packaging bags and beverage packaging bags from 2006 onwards. It will enforce the product certification control system (ie, 3C certification) and must achieve the hygiene of composite food packaging bags. standard. Only plastic food packaging products that meet the 3C standard can be listed. This is a great challenge and a great opportunity for more than 10,000 color printing and packaging companies and ink manufacturers across the country.

Ink ink applications are mainly based on flexographic printing and gravure printing. The inks widely used abroad have good environmental protection and good ink performance. They are mainly characterized by stable ink, high brightness, strong coloring power, high attachment fastness, and the drying speed can be adapted to the needs of printing speed. Four-color overprinting and spot color printing Can be. Water-based gravure inks have been widely used in the printing of packaging papers, cardboards, paperboards, and other paper products. This is due to the fact that paper products are evaporatively dry and absorbable and dry. Water-based inks are used in flexographic printing. China is currently developing rapidly in China. More than a dozen ink factories have developed flexographic inks. The proportion of ink in the flexo press has increased. However, the application of water-based gravure ink in plastic film printing is still in its infancy. This is mainly due to the fact that water-based inks have the ability to adhere in gravure printing, and the speed of printing, the speed of light, etc., cannot fully meet the requirements of solvent-based inks. The WE-type gravure water-based ink has enabled new products in the field of plastic film gravure printing that can completely meet the required standards.

Plastic film gravure water ink performance comparison table:
(The film used was corona-treated with a surface tension of 38 dyne/cm BOPP film)
Color tinctorial strength Gloss fineness (micron) Coating -4 Viscosity seconds / 25 °C Initial dryness mm/30S25 °C Depth 5/28 °C Paste fastness Knead fastness Domestic company sample Red big 20 115 6 123 Poor Good sample for a foreign company is very good, big, red, very good. 22 22 12 215
WE ink sample is very good, big, red <10 26 17 202

The conclusions of the use of the three types of water-based gravure inks in testing and production: The main deficiency of 1# products is poor adhesion, slow drying, and can be used in production, but fundamental problems are not solved. The 2# product can be used on a 30-100m/min gravure press, but there is a lack of attachment fastness.
The BOPP film printed with the concave WE-type water-based gravure ink is boiled (100°C) and boiled for half an hour. The BOPP film is then taken out and blow-dried. If the stickiness is the same as before boiling, the ink does not fall out. It was put into a 30% concentration of hydrogen peroxide solution at 40°C and then removed after drying for 2 minutes. The gloss was unchanged and the adhesiveness was unchanged. The use of production proof in the printing, WE type water gravure ink its performance has fully meet the requirements of gravure printing machine, in the attachment fastness, drying speed, color concentration and gloss and other major performance indicators have reached the international advanced level of similar products .

Plastic film gravure water-based ink use matters needing attention:
When used, the viscosity of the ink can be adjusted with water, and the viscosity of the ink is controlled to be 15-25 seconds/25°C. If the viscosity is too high, the transfer performance of the ink may be poor, and the defects such as a dirty plate and a paste plate may be easily caused. If the viscosity is too low, the color may be light, the dots may be enlarged, and the ink may be uneven. Plates are either electro-engraved or laser-engraved, and the plate depth should be between 15-25mm. The shallow version can increase printing speed and save ink. Excessive printing will affect the print speed, and it consumes a large amount of ink and is prone to blocking. The drying temperature is 50-60, and the air volume is large, so that the ink transferred to the film can be dried quickly. Before printing, after the ink is poured into the ink tank, allow the plate to idle for 2-3 minutes, playing the role of humidity plate and stirring. If the printing process is temporarily stopped while observing the print product, the printing plate must not be stopped in order to prevent the ink on the plate from drying and making the cork plate. Such as plug version can be used special wet cleaning liquid washing. Before printing, adjust the viscosity of the ink according to the depth of the printing plate, and try not to add water to the ink during the printing process. Just add new ink to ensure consistent color and color density before and after printing. Immediately after the printing, the plate should be cleaned, the remaining ink should be installed, the clean water should be put into the tank, and the plate should be rotated to wash the ear, or 3% detergent solution should be added for cleaning.

The WE type water-based gravure printing ink launched by Beijing Inco Chemicals Co., Ltd. is willing to work together with friends in the packaging and printing industry to achieve mutual benefit and win-win, and to serve our country's green packaging printing wholeheartedly.