The ABCs of CIJ Ink Formulation

There’s a lot to love about continuous inkjet printers. From high printing speeds to wide substrate compatibility, CIJ printers have been prized by industrial line operators ever since they arrived on the market nearly 60 years ago. 

Capable of 24/7 uninterrupted marking even in harsh facility conditions, continuous inkjet printers are used to complete some of today’s most challenging marking/coding applications, including:

In these scenarios and others, CIJ users rely on their printers to mark thousands of products a day on a consistent basis. With the help of proper maintenance, line operators can successfully use their CIJ printers to efficiently mark their goods with variable data and traceable batch codes. 

However, even if one uses the best CIJ printer available, they won’t be able to mark their products without the right ink formula. After all, printing success is only possible when one uses an ink that is specifically formulated to work with their materials.

The Goals of CIJ Ink Formulation

When creating an ink formula, developers aim to meet a few core objectives. The most important goal is for the ink to work in the intended printer and printhead.

Today’s printer market is filled with different technologies that pressurize and propel ink in different ways. Thermal inkjet printers, for example, use heating elements to pressurize ink and expel droplets onto a substrate. When creating a TIJ ink formula, developers work to ensure that the ink can remain stable when exposed to consistent heating cycles. 

CIJ printers don’t use heat during the printing process. Instead, they use pumps to pressurize ink into a stream, electric plates to stratify the ink stream into individual droplets, and piezoelectric printheads to propel the ink onto materials. As such, all CIJ ink formulas must be able to:

  • Remain stable while being pressurized
  • Resist blocking the nozzle
  • Reliably form into droplets

Beyond these basic necessities, CIJ inks are also formulated with specific applications in mind. For example, a formula made for wire/cable extrusion must have:

  • Compatibility with non-porous materials
  • Transfer-resistant properties
  • High-contrast appearance 
  • Solvent-resistant properties

In many cases, certain CIJ inks can be used for multiple applications if they require the same properties. Inks designed for cold-fill applications are often recommended for other applications in which condensation is a main concern. 

Generally speaking, CIJ ink developers will focus on the following properties to develop application-specific formulas:

  • Substrate compatibility
  • Drying times
  • Image resolution
  • Color choice
  • Resistance against specific elements (e.g., light, humidity, temperature, touch, etc.)

Next, we’ll take a look at what substances are included in CIJ ink formulation and how developers turn them into ink formulas. 

CIJ Ink Formulation: Essential Components and the Creation Process

Although CIJ ink components will naturally vary from formula to formula, certain elements will be found in nearly every ink on the market. These substances include:

  1. Dyes or pigments to color the ink
  2. Dispersing agents (for pigmented inks) to aid ink drop stratification 
  3. Wetting agents to help control surface tension
  4. Humectants to prevent dryness
  5. Penetration enhancers to improve application properties
  6. Polymer binders to enhance substrate adherence
  7. Solvent to improve viscosity and dry time

As a trade secret to many in the industry, the basics of ink development start with a proprietary process. Using these components and others, ink developers create formulas using the following steps:

  1. Consider the substrate and application: As the base of the printing, the substrate needs to be compatible with the process.
  2. Introduce Solvent: Solvent is used to dissolve the resin and dye in order to form a viscous mixture.
  3. Introduce Resin as the Base of the Formula: All subsequent materials will bind to the resin in order to form a proper mixture.
  4. Add Dye or Pigment: The dye or pigment will give the formula its color and enable visibility on the substrate.
  5. Mix Fluid: All other ingredients are added together and mixed to create a homogenous solution.
  6. Filter the Solution: The ink solution is placed through a filtration system to remove all insoluble elements.
  7. Test: The filtered ink solution is tested to ensure that it can successfully complete the intended application. 

After these six steps, the ink is ready to be packaged and sold. 

Searching for a New CIJ Ink Formula? InkJet, Inc. Can Help You Find It

For over 30 years, InkJet, Inc. has been developing and selling CIJ inks for a wide range of applications. Today, our portfolio is filled with specialty inks, aftermarket alternatives to popular OEM formulas, and custom-built products. Whether you need ink for glass bottle marking or cardboard box printing, InkJet, Inc. can help you find the perfect ink solution to meet your printing needs. 

To find the perfect CIJ ink formulation for your needs, contact us online today or call 1(800) 280-3245