Frequently Asked Questions

Q: I'm confused about inks! What are some tips that I should know?

We've compiled a list of tips to help relieve your confusion:

Ink Tip #1: Ink Components
One basic formula is common to all printing inks: pigment + vehicle + additives. Pigment yields colour, vehicle makes it flow. Additives contribute special qualities that help pigment and vehicle achieve a desired effect. Three simple elements; a universe of possibilities.

PIGMENT These tiny solid particles give printing ink its colour, and also affect the ink’s opacity and permanence. The source of pigment can be minerals or mineral compound colours like Titanium Dioxide White, Chrome Yellow, Iron Blue — or organic compounds — Yellow Lake, Rhodamine Red or Peacock Blue.

VEHICLE The vehicle is the fluid component in ink. These days soya oil is a common vehicle, but linseed oil, petroleum and resin vehicles are also widely used. The vehicle carries the pigment, and binds it to the printed surface. Its properties also affect the gloss and hardness of the dried ink. Different vehicles have different viscosity, consistency and flow characteristics — the ink’s "body". These result from adjusting the blend of "long" or more liquid varnishes and "short" or stickier gelled varnishes. The perfect blend varies from job to job, relative to other factors such as paper stock. The goal is to create a vehicle which will print a crisp, sharp dot, or a perfect solid.

• ADDITIVES Colour and varnishes alone will not make an ink that stands up well in a high-speed, high-volume printing press. A range of additives is blended in for different applications and end use requirements — basically, to enhance printability.
• ANTISKINNING AGENTS Without these, some inks will dry too rapidly, forming a thin skin on top of the ink.
• BINDING VARNISHES and BODY GUMS These help produce a sharper image. They also improve drying properties and prevent chalking — pigment powder separating from the vehicle.
• DRIERS, OILS OR MINERAL COMPOUNDS The most common include maganese or cobalt — that help ink dry more quickly and consistently.
• SOLVENTS and REDUCING OILS These reduce the tack or stickiness of the ink, and also help the ink to penetrate and to set rapidly.

Ink Tip #2: Ink Sequence
Some say ink sequence makes a discernible difference. Others say it doesn’t. They are probably both right, depending upon the type and composition of ink and paper stock used. A common rule of thumb for ink sequence is "dirty to clean" — darker to lighter — in four-colour process, Black-Cyan-Magenta-Yellow. Some like to print the Yellow first, to allow its light to shine up through the other colours. But this can lead to trapping problems or contamination of the subsequent colours by the Yellow.

Ink Tip #3: Fluorescent Inks
For colours that you want to vibrate off the page, fluorescent inks may do the trick. The pigment in fluorescent inks is composed of fluorescent dye pulverized into a powder. There are 14 fluorescent colours to choose from, each a colour too bright to be natural, but too brilliant to ignore. Amazing results can be achieved by replacing Cyan, Magenta, and Yellow with their fluorescent equivalents. Or, using one fluorescent ink in combination with process colours can give a real boost to the result.

Strange as it seems, the inks that carry these surreal hues tend to be weak — they lack saturation. So a double hit is often necessary to bring a fluorescent ink up to its full vibrant potential. Also, consider the intended shelf life of your job. If it is a poster, for example, that will see a lot of sun, its best to steer clear of fluorescent — red, especially. They have poor light fast qualities.

Ink Tip #4: Metallic Inks
Metallic inks add a touch of class to a print job, simulating the lustre of precious metals. But all that glitters is not gold. "Copper" ink does contain copper, but what looks like gold in "gold" ink is really a mixture of copper and zinc; aluminum gives "silver" ink its silvery sheen. Metallic powders — actually microscopic flakes — are added to specially formulated vehicles which will cause these flakes to "leaf" properly — lie flat and not edge-on — and bind to the paper stock.

There are stock metallic inks, but any colour can be turned into a metallic by adding an appropriate metallic paste to it. Silver works best with blues, gold with yellows, etc. The resulting combination will, however, have a different hue from the basic colour.

Just as your silverware can tarnish, oxidation and fingerprinting can be a problem with metallic inks. A solution to eliminate this is to add a press varnish printing over the areas. The metallic will be protected by its lustre but will be toned down.

Metallic inks are especially prone to metamerism, an optical effect in which colours appear different in different lighting conditions. Be aware of this when attempting to achieve a custom metallic colour. A match that may look exact in the lab, or even under colour-corrected lights, may shift away when placed in the lighting environment where your job will be used most. So check out your ink sample under the light in which the finished product will be used.

To help eliminate the dull appearance of metallic ink on uncoated stock, consider printing a sealer coat or a varnish under the metallic first.

Ink Tip #5: Getting the Colour You Want
Painting the rainbow using only a handful of colours is part of the wonder of four-colour printing, but blending colours can only take you so far. A good rule of thumb is to not allow the total tint percentage to exceed 300%. A higher total leads to muddy colour: in this case, the sum is less than its parts.

A hunt for a perfect colour match is really the pursuit of the hidden formula. The chase starts with the desired colour sample. Pull out your colour swatch books, and chances are you’ll meet your match. But sometimes the quarry is more elusive. In that case, an ink specialist will add increments of the basic printing colours to a standard colour ink, usually 5% at a time, until the match is exact.

To avoid specifying a CMYK combination that is unprintable, we encourage: 1) Referring to the Pantone Process Colour Imaging Guide 1000. This printed system shows side by side 1000 spot colours and their CMYK simulation. 2) Better communication of your expectations with your printer. By following these recommendations you can assist in eliminating this problem.

Ink Tip #6: Pearlescent Inks
Pearlescent inks, used tastefully, yield a wonderful three-dimensional sheen, — especially when used on highlights. Their base pigment is mica powder of a flaky consistency that is treated with titanium dioxide, and is used much like a varnish. These flakes are part of what gives pearlescents their sense of depth, but they do not always run well on press, and tend to pile. Pearlescent inks also have a tendency to yellow over time. So use them sparingly and advisedly — for that special touch.

Ink Tip #7: Gas Ghosting
The first printed side of a sheet must be completely dry before printing on the other side. Otherwise, there is potential for "gas ghosting". As ink dries, gases are released. On occasion the gases from the first pass get trapped between the sheets in the paper pile. These trapped gases leave a ghosted image in the ink on the sheet above. So, if your design creates a situation like this, make sure your job schedule allows for the required time to dry.

Ink Tip #8: Matte Press Varnish
The powdery surface of matte inks is prone to scuffing. So if you are printing a piece that will undergo wear — like a catalogue cover — consider using a matte press varnish instead. Or, used in combination with matte inks, a matte varnish can produce a rich, matte glow.

Ink Tip #9: Clear Extender
If you are using a special colour which contains very little translucent white in its formula, and the effect you desire is a weaker or translucent colour, ask for a clear extender to be added to the special ink.

Ink Tip #10: Foil Stamping
If foil stamping is part of the manufacturing process, the need for careful ink formulation is even more meaningful. One important ink additive is wax. This wax component makes it difficult for the foil to adhere to the stock. Reducing the wax solves the problem of foil adhesion, but adds another problem. To combat this, a low percentage of Teflon is added to the ink mix instead.

Ink Tip #11: Printing Solids
Printing large areas of solid colour is often a risky proposition. There’s something about that vast monotone expanse that seems to exaggerate printing limitations. There are solutions to assist in reproducing large solids. The simplest route to consider is choice of paper stock. Premium grades have printability qualities: a smoother surface, superior fibre construction, better quality coating. These attributes give the printer a head start in the difficult task of laying a solid colour evenly. Another consideration is the introduction of a booster or a second hit of ink. This provides a much thicker layer of ink making the printed colour appear richer. Combining these two solutions will assist in achieving your expectations.

Ink Tip #12: Process vs. Special Colour Inks
The three process colours Cyan (a blue), Magenta (a red), and Yellow — used in combination, along with black, are the primary colours of four-colour printing known in shorthand as CMYK.

But, for simulating some shades along the spectrum, they fall short. If the colour you want is one of these, then you may opt for a special premixed ink colour, often as a fifth colour. How do you make the call?

A question to ask, "Is matching an exact colour really important?" If yes, then a special colour will supply the expected results. The appropriate colour can be selected by consulting a colour matching system, the most popular being the Pantone Matching System. If an exact colour match is not as important to you, or budget constrains, then results can be achieved by simulating actual Pantone colours with percentage screens of the process colours. The limitation is that only 60% of Pantone colours can be simulated using this method. Some colours, such as Pantone 2727 blue, are especially problematic to create using process colour. If that’s your colour choice — or a characteristic colour in the original art you want to reproduce — you will need to go beyond the limitations of process colour by using a custom spot colour. Printing a large area of one solid is usually best achieved using a special ink, rather than a match of process colours. Likewise, to achieve sharp character definition when printing coloured type, you’ll have better success using a special colour.

Ink Tip #13: Translucent, Opaque and Matte Inks
Most press inks are inherently transparent and glossy, which enables the ink layers in a four-colour process job to work together to create a wide gamut of colours. Sometimes a more subtle, low-key matte effect is desired, or you don’t want underlying colours to show through. These are the times to specify matte or opaque inks.

Matte ink granules possess a powdery consistency. As the ink dries, they float up to the surface, giving it a rough texture, unlike the smooth outer skin of normal inks. This rough texture diffuses more light, muting the ink’s gloss.

Opaque ink pigments block more light, so less will show through. They can be used alone, but some — especially Opaque White — are used to ad opacity to other colours. Say you want to print a light colour — like yellow — on a dark stock, printing an opaque white first — often two hits, dry trap are required — will help prevent the stock colour from influencing the ink colour printed on it.