INKS

Dyeing to be natural

Inks generally have two components: a pigment and a solvent (or put differently: a colourant and a vehicle). They fall into one of four separate classes, namely aqueous, liquid, paste or powder. We have compiled a guide as to how the different inks are formed and how their characteristics differ.

Colourants

With ink, either natural pigments or dyes are used, each with their separate characteristics.

Pigment

Pigment inks are more colour-fast, but they are also more expensive, less consistent in colour, and have less of a colour range than dyes. Pigments are solid, opaque particles suspended in ink to provide colour. The pigment molecules typically link together in crystalline structures that are 0.1–2 µm in size and comprise 5–30 percent of the ink volume. Qualities such as hue, saturation, and lightness vary depending on the source and type of pigment.

Benefits of using pigment-based inks

• Resistant to most exterior factors. • Can last for decades on paper. • Doesn’t fade out over time. • Dry and adhere fast to surfaces.

Disadvantages

• Colour can be a bit dull. • Quite expensive & difficult to find. • Dye

A dye is a colourant. Dye-based inks refer to a colourant that is dissolved in a liquid. Most dyes are dissolved in water, but other liquids like alcohol or other chemicals can also be used to increase durability or enhance the colour, or just make the ink easier to use.

Most dye-based inks come in a broad palette of colours and offer outstanding visual results. Transversely they are prone to fading and oxidise easily over time.

Benefits of using dye-based inks

• Beautiful colour quality. • Easy to spread and paint with. • Affordable and easy to find. • Adheres to almost any surface.

Disadvantages

• Tends to fade out fast. • Not resistant to external factors.

Colour Quality

Considering the overall quality of the print or traces, dye-based inks perform amazingly well. The vibrancy, brightness, and overall density make dye inks outstanding for printing that rely heavily on colour quality. In fact, dye-based inks have a broader colour palette and more shades than pigment-based dyes.

Additionally, dye-based inks don’t have what’s called “metamerism.” This refers to an effect which occurs in pigmentbased inks. Metamerism changes the colour appearance depending on the light. Dye-based inks will always look the same, but whilst pigment-based inks are not as bright or vibrant and don’t hold colour the same way against the light, they’re still decent.

Durability

Durability and resilience are important factors and dye-based inks are not the best in this regard. This is because the dye does not hold to the fibres but instead gets absorbed. When it is absorbed, the ink is more likely to break down as the paper breaks down, which leads to fading and smudging.

Dye-based inks are less resistant to UV rays and water. Constant exposure to sun and moisture can make dye-based inks lose colour and blur. Conversely, pigment-based inks hold much better

onto paper and other surfaces because they don’t get absorbed. Instead, it adheres to the surface, and can withstand different factors that may affect the paper but not the ink.

Pigment-based inks are much more resilient against sun and water and can handle most exterior factors, making it much more durable than dye-based inks. Dye-based inks begin to fade out after the first 10 years. After 50 years, the ink may not be the same anymore, losing much of its vibrancy and looking totally different from the original version.

Pigment-based inks can be unaltered after 50 years and in some cases have lasted 200 years. In short, we can say that pigment inks are more durable and resistant overall.

TYPES

Pen ink - Oil or water based using dyes for colour.

Printer ink - Most colour printers follow the CMYK (cyan, magenta, yellow, black) model. To make new colours and create an image, the printers will layer tiny dots of the four printer colours.

Edible ink - This is made from water, sugar, and approved colorants. They're safe to eat and can be used as cake toppers for instance.

Tattoo ink - Most tattoo ink solutions use pigments rather than dyes to achieve the desired hue.

Erasable ink - The ink is made of a liquid rubber cement, which is removable via friction and heat.

Phosphorescent ink - Use strontium aluminate phosphors. These absorb and store light energy. Once it's dark, the energy is converted into visible light known as “the glow”.

Fluorescent ink - Fluorescein is used to make highlighter ink and it gives it a neon colour. Different additives are used for colours. Pyronine is used to make yellow highlighters.

Adhesive ink - Temporary tattoos and decals are made from regular ink with a Invisible ink - Can be used to write a secret message and then uncover it using heat or light.

Invisible ink in the home

Many items in your kitchen can be used to create invisible ink, including lemon juice, milk, clear soda, and vinegar. Use an earbud dipped in the liquid to write on paper and then hold it over a candle or other heat source to reveal the writing. �

ACKNOWLEDGEMENT

Cdw.com, Wikipedia