Brookfield BROOKFIELD: Viscosity control saves considerable inks

There is a problem with the ink film, it is easy to see if it is very thin, but it is difficult to detect by eye when it is too thick. Once the main color is achieved, the main color will not change even if the ink film becomes thicker. For the naked eye, the difference between 0.001 inch and 0.0001 inch thick film is very small, and without accurate viscosity control, a lot of expensive ink may be wasted.

The automatic control system continuously senses the viscosity of the ink, and will output a signal when solvent needs to be added, thus preventing the accumulation of wasted ink. Controlling the slightest change in viscosity can make all the difference to successful ink management, especially in the low-viscosity area of ​​thinner inks in use today.

important variable

Modern flexographic printing operations put pressroom supervisors, plant managers and quality control managers in charge of saving time and ensuring proven performance in flexographic printing. It is very important that the ink adheres to different substrates without fluctuations and maintains the correct color density. Whether producing corrugated boxes, flexible packaging, color boxes, or pre-printed linerboard or labels, reliable viscosity and pH control is required to ensure uniform application of ink.

Viscosity may be an important variable in printing. Unless it is closely controlled continuously, good color, uniform ink coating and accurate color matching will not be obtained. With today's higher cost solvent-based or water-based inks, controlling ink viscosity can provide considerable cost savings for medium to large or even small print runs.

There are other variables that can affect the quality of the final product, but none as quickly or as dramatically as viscosity. After establishing other mechanical and setup parameters for printing, such as nip, speed, paper selection, etc., the first parameter that controls ink transfer to the substrate is viscosity.

In order to meet the needs of modern printing, very complex ink products have been formulated today. The properties of the printing substrate determine the properties the ink needs to have, whether it is a water-blocking ink for outdoor use, a scratch-resistant ink for shipping containers or a special odorless ink for food packaging. Satisfactory printing performance is usually achieved by strictly adhering to the ink manufacturer's specifications, otherwise printing problems will occur. The effect on print quality and color values ​​is very noticeable.

increase product profit

Numerous papers can demonstrate that a 1 second increase in viscosity leads to a 25% increase in ink consumption. Other aspects of the operation that can increase product profit when properly controlled should be kept in mind:

• Reduced setup waste

• Conserves ink and solvents

• Reduced setup time

• Eliminates off-spec product and, regardless of the wide range of printing press ink variations, standardized viscometer setups have many inherent cost efficiencies including:

• Uniform ink application, less ink waste

• Less downtime

• easy to clean

real application

Recently, an operation station that prints lottery tickets for government, corporate and retail outlets installed an in-line viscometer on a narrow web flexo press. The company currently runs 12-hour shifts and produces millions of lotteries each year for many multinational corporations. “We used to use Zahn cups, but there was so much inconsistency,” explained the pressman, “You get different measurements depending on the operator guide reading. Sometimes you get a thicker film and sometimes a thinner film, and the flow behavior of the ink deviates from the .We also have problems with the pump, sometimes the ink is too thin and results in a clear layer instead of opaque. But since installing the in-line viscometer, the viscosity has held up really well. As long as the solvent tank is full, I can run it all day with no worries Leave it alone."

Choose an Automatic Viscometer

Print managers must select a viscometer based on product needs, which depend on many factors, including operator approval, consistent measurement and control, compatibility with existing machines, expected cost savings, and maintenance. Uniform viscosity measurement and control achieves ink reduction and cost savings, and long-term running excellence is also a cost savings for operations and service.

Some of the major viscometer manufacturers offer a number of warranties and maintenance contracts to ensure maintenance of the in-line viscometer to get the consistent product you need.

advantage

In a pressroom, the primary function of a viscometer is not simply to measure viscosity accurately, but to maintain ink ratios at a predetermined level thereby ensuring the economical use of expensive inks and of course in line with the quality of the final product. In summary, as a print manager or operator, installing a modern viscosity measurement and control device allows you to:

• New print quality and consistency.

• Significantly reduces waste while driving.

• Reduce non-conforming product.

• Quick payback through ink and solvent savings.

• Reduce flushing.

• Better ink adhesion.