Ink Quality

The quality of an ink is derived from its formulation, specifications, raw materials, and quality control procedures.

Ink Formulation

The specific components of the ink formulation would include such things as pigments, solvents, resins, and binders. Every ink formulation is unique based on print head type and printer characteristics.

Ink Specifications

• Particle Size: All of Triangle Digital’s inks are submicron
• Surface Tension: Determined by the print head which usually is between 27-32 dynes.
• Viscosity: Viscosity requirement are determined by the type of print head for which the ink is formulated.*
• Rheology: All pigmented inks are thixotropic by nature. When formulating an ink, it is important to take into consideration rheology and the ink train.
  

Raw materials

Triangle Digital’s IQC (Incoming Quality Control) Program ensures consistency and reliability in all raw materials entering the production facility. Being the second largest manufacturer of digital inkjet inks, Triangle Digital often sets the standards for raw material suppliers globally.

Quality control

Triangle Digital has a progressive Quality Control Program which ensures consistency and reliability from batch to batch. More than 37 measurements are taken during production, filling, and post manufacturing to guarantee consistent jettability, color, viscosity, and aging.

Ink Colors

Digital prints are made up of many colors. Use of more colors will offer a wider color gamut when printing.
Primary Colors: Cyan, Magenta, Yellow, and Black (CMYK). Inkjet ink’s standard color gamut is larger than standard SWAP color.

Light Colors: Using light versions of primary colors will give higher print quality. Light colors are typically 12-15% of the density of the dark colors.
Secondary Colors: Also known as “intermediate” colors. These are typically orange, green and purple. There is a very low demand for these types of colors due to limitations in pre-press and RIP technology.

Outdoor Durability

The outdoor durability of a print is determined by many things but no limited to: pigments quality, and raw materials used in product formulation and production. Triangle Digital has made a commitment to high quality and consistency.

• Quality Pigments will provide a quality product with increased protection against UV light and basic elements of the outdoors. Triangle Digital secures its raw materials from only the industry’s top suppliers to ensure 100% quality.
• Triangle Digital typically will warrant solvent based ink for up to 2 years durability outdoors; 3 if using a recommended ClearFlex UV coating.
  

Adhesion

In the Wide Format market, Triangle Digital has superior formulation in our Mild Solvent inks, offering much greater adhesion to uncoated media. The adhesion of an ink is determined by the binders and the solvents used in the ink formulation.

Printability

The key issues that affect printability are dry time, ink starvation, overspray, wetting, and platen temperature.

Dry Time

This is determined by the evaporation rate of the ink and the solvent retention by the media. When formulating an ink, the following need to be considered: head type and speed of the printer into which the head is being integrated. Developing a properly matched system will limit downtime and increase production output.

Ink starvation

This occurs when ink is not flowing to the head correctly. In many cases, temperature has forced the viscosity out of specification.

Overspray

This occurs due to improper droplet formation caused by either improper voltage to the head, print speed not matched, or a change in viscosity. Often you will see this on the sides of prints or in white text. Another term for this would be satellites.

Wetting/Bleeding/Pooling

This is a direct effect of the surface tension of a substrate not matching that of the ink set. Using the proper media, with the correct settings and the RIP to minimize over inking, will generally resolve this issue.

Platen Temperature

The temperature should be set differently for each media using the lowest possible temperature to ensure longer print head life. Too high of a temperature will result in the ink drying too fast, often leading to clogged print heads.

Ink Shelf Life

Inkjet ink generally has a shelf life of approximately one year. This was a major issue in the industry as aging resulted in sedimentation. Storage conditions are an essential part of maintaining an ink’s jettability. Please see labels for proper storage conditions. All digital inks should be kept on a shelf, at least one meter off of the floor. Once a bottle has been opened, it is important to retighten the lid to keep evaporation from occurring.

Viscosity

Ink viscosity varies with temperature. The higher the temperature, the lower the viscosity. This is the reason why ink should be kept at an ambient temperature for several hours before using in any printer. Room temperature should be kept between 18°C and 25°C. A higher or lower temperature could lead to overspray or starvation as the ink’s viscosity will change. For example, there could be a difference of 3 centipoise for an ink at 23°C whose is standard temperature is 27°.

Return to Support Overview