Advantages and disadvantages of water-based inks

When it comes to the advantages of water-based inks, it is environmentally friendly, and the disadvantages are that the printing effect is not as good as solvent inks, and the price is not high.

1. Advantages of water-based ink:

1. The main components of water-based ink are acrylic resin, pigment and water, plus a small amount of additives. According to the CNAS test report, the VOCs content is even lower than 1%. It can be said that the emission of VOCS is very small, which is enough to prove It has great advantages in environmental protection, not only reducing air pollution, but also not harmful to users and printing operators. More demanding fields such as children’s toys have been widely used, and even some pharmaceutical industries have begun to use water-based inks for printing.

2. Disadvantages of water-based ink:

The effect of water-based ink prints is mainly reflected in the following three aspects: low adhesion, poor gloss, and slow drying. We only do one analysis at a time.

1. The adhesion of water-based ink is low

The size of the adhesive strength is closely related to the surface tension of the material. For example, the surface tension of PE and BOPP is 32 dyne, while the surface tension of water is 70 dyne, so usually water-based inks cannot be printed on plastic films. With the development of corona technology, the surface tension of plastic film can be increased to 38, wax in water based ink additives, which can well meet the printing requirements of water-based ink, and can resist scratches and water after printing. Therefore, the adhesion of water-based inks is indeed worse than that of inks, but the requirements can be achieved through some auxiliary means, so the adhesion problem is not big.

2. The gloss of water-based ink is poor

Glossiness is a natural disadvantage of water-based inks, but this disadvantage has gradually narrowed, and it is not as obvious as some people say. In order to solve the problem of glossiness when producing water-based inks, manufacturers have done a lot of work on color, such as the use of After several years of hard work, it can be seen that the improvement effect is very obvious.

3, water-based ink drying speed is slow

Water-based ink evaporates water, solvent ink evaporates solvent, there is an essential difference between the two, so the evaporation of water must be slower than the evaporation of solvent, but now with the technical progress of various high-speed flexographic printing machines, the printing speed can be Up to 450 m/min (as shown in the video), so the drying speed figure has now been broken. It can be said that there is no longer the problem of slow drying.

The water-based ink must be more expensive than the ink, which is determined by the raw materials of the two inks. Although the water-based ink uses less oil than the solvent-based ink due to the same printing area, the actual oil consumption of the combined ink is not higher than that of the solvent. There are more type inks, and the larger the printing area, the smaller the gap between the two inks. In addition, because of the pollution of solvent-based ink to the environment and the damage to the operator’s body, these are the reasons why we choose water-based ink, even if it increases a little cost, it is acceptable.