HEPI Academy
? What is the difference between Water based ink and Solvent based ink
Water-based and solvent-based inks are two different types of inks used for flexographic printing. Here are some differences between them
Composition: Water-based inks are made from water, resins, and pigments. Solvent-based inks are made from solvents, resins, and pigments
Drying time: Water-based inks take longer to dry compared to solvent-based inks. This means that printed materials using water-based inks may require more time to dry before they can be handled or packaged
Environmentally friendly: Water-based inks are considered more environmentally friendly than solvent-based inks because they have a lower VOC (volatile organic compound) content. This means that they release fewer harmful gases into the environment
Ink penetration: Water-based inks tend to penetrate the substrate more than solvent-based inks. This can be an advantage or disadvantage depending on the type of material being printed on
Print quality: Both types of inks can produce high-quality prints, but solvent-based inks tend to have better color intensity and clarity, especially on non-porous materials like plastic and metal
Clean-up: Water-based inks are easier to clean up than solvent-based inks, as they can be cleaned up using water. Solvent-based inks require more care when cleaning up, as they can be harmful if not handled properly
In summary, water-based inks are more environmentally friendly and easier to clean up, but they take longer to dry and may not produce as vivid colors as solvent-based inks. Solvent-based inks are better suited for printing on non-porous materials and offer more intense color clarity, but they have higher VOC content and require more care during cleanup. The choice between the two types of inks ultimately depends on the specific requirements of the printing application
Flexographic printing machines, types and differences
There are different types of flexographic printing machines, each with its own advantages and disadvantages. Here are some of the most common types
Stack Press: Stack presses are the most basic type of flexographic printing machine. They consist of multiple printing units stacked on top of each other, with each unit printing a different color. Stack presses are relatively inexpensive and easy to operate, making them a good choice for small or medium-sized print runs. However, they have limited printing capabilities and are not suitable for printing on non-absorbent materials
Central Impression Press (CI Press): CI presses use a single large cylinder that rotates, with each printing unit mounted around the circumference of the cylinder. The substrate is fed through the center of the cylinder and is printed as it passes through each printing unit. CI presses are versatile and can print on a wide range of materials, including non-absorbent materials like plastic films. They also offer high printing quality and precision. However, they are more expensive than stack presses, require more skilled operators, and have a longer set-up time
In-line Press: In-line presses are similar to stack presses but are designed for high-speed production. They consist of printing units that are placed in-line with other finishing processes, such as die-cutting or laminating. In-line presses can produce large volumes of printed material quickly and efficiently, making them suitable for large-scale production. However, they require a significant investment and can be difficult to operate
Wide Web Press: Wide web presses are designed for printing on large materials, such as packaging materials or paper rolls. They can print up to eight colors and produce high-quality prints. However, they are expensive and require a large production space
In summary, each type of flexographic printing machine has its own advantages and disadvantages. Stack presses are inexpensive and easy to operate but have limited printing capabilities. CI presses are versatile and can print on a wide range of materials but are more expensive and require skilled operators. In-line presses are designed for high-speed production but require a significant investment. Wide web presses are suitable for printing on large materials but are expensive and require a large production space. The choice of machine depends on the specific printing needs and budget of the printing project