Toby Burnett discusses the need for multicolour printing and the importance of accurate proofing…
A continuing trend in packaging printing is the increasing complexity of jobs and the use of multicolour printing, while meeting brand owner demands to reduce time to market at the same time. Many packaging jobs require different combinations of inks, substrates, screening, and other variables. A chocolate wrapper might have two browns; fruit juice cartons may have oranges, greens and reds.
The inability to accurately proof spot colour halftones and overprints either conventionally or as part of extended colour gamut process poses one of the biggest challenges for packaging producers. There has not been an effective and accurate way to predict the behaviour of overprinted spot colours without physically printing them together.
For example, if a 40% spot colour green interacts with an 80% spot colour ‘red’ (green on top of red), what is the resulting colour on a flexo press? Until now, we didn’t know. The underlying technology to accurately measure and proof this behaviour had been missing.
To make it even more complex, each printing process overprints differently. Flexo offset and gravure all overprint differently producing different end results. Then, consider the unique information needed to accurately predict the overprint behaviour of two custom spot colours: on a given flexo press, with a given anilox, at a given line screen, with food grade inks. The industry has become adept at making solid colours appear similar across different printing processes, but that’s about it.
Typically for printing processes that rely on a combination of inks you need to print a complex test chart. This will enable the production of an accurate ‘fingerprint’ of the press that is used to create profiles for colour management processes. Not only is this costly but it is also time-consuming, and designs that rely on having fingerprint profiles can be held up while this data is produced. Additionally some proofing systems will still struggle to show the effect of printing multiple inks together due to the limitations of current technology. So, in these cases press passes or wet proofs are unavoidable, further lengthening the process and increasing production costs.
This is why many brands and creative houses work in the FOGRA 39L standard with generic spot colour information and send the files to a repro house. Usually creative stakeholders will not see how their designs will really look on press until the job is back from repro, where a more accurate proof is generated. Not only does this cost both time and money, but in cases where the result is not satisfactory, delays in production or increased costs can occur as the job is reproduced. Consequently brands and their respective agencies will often utilise a known set of colours, or suppliers; potentially limiting their creative aspirations and competitiveness.
With GMG OpenColor a new methodology has been introduced that predicts actual ink behaviour, on a specific substrate for each printing process without the costs or delays of traditional press fingerprinting. It resolves this complex packaging problem and provides better results, with less information.
New spectral modeling algorithms are coupled with spectral ink measurements that analyse the properties of each ink colour, as well as the substrate’s colorimetric properties. This information is applied to a specific printing process (flexo, offset, gravure). A profile could be created with just the solid patches of the spot colours on the substrate, although better results would be achieved if multiple steps (50%, 30%, 10%, etc.) of the colour were measured, improving the end result. Traditional press fingerprinting charts are supported, and the new technology can use existing press characterisations to refine accuracy.
The technology also allows the substitution of the substrate within the profile so it can be used to demonstrate the effect of stock changes early in the creative cycle. In this case, the colour values of one substrate can be replaced by the values of another substrate. In many cases, the required spectral data can be gathered from control patches included in actual production runs or previously printed products.
Profiles can be archived, and re-used for future designs, or edited simply by the addition of new inks, the removal of unused inks or a change in print sequence; making the system extremely versatile in product design and creative processes. Allowing users to get the proof right first time around.
For a printer, this has a profound effect on performance. It allows for more packaging standardisation and shorter production cycles. Special products made for a limited time such as Valentine’s Day or Christmas could be more economical, because colour testing would be quicker and easier. Colour and ink combinations that are affected by food safety can be tested much more quickly. Ultimately, with less time spent on make-readies and press passes, wastage is reduced.
Brand owners and creative houses alike benefit from accelerated production times. A colour correct proof first time around has the knock-on effect of giving more time to the creative process, meaning users can experiment with swapping colours in a design and get an accurate proof in-house, increasing creativity in a demanding sector.
For the repro house, it means having accurate proofs without incurring the fingerprinting costs typically associated with establishing a client; reducing production times and overheads while increasing client satisfaction.
What does this mean to the packaging industry?
Globally, current press fingerprinting within offset, flexo and gravure packaging printing costs millions of pounds every year, and delays production. This high cost often yields poor results, thus raising costs even further. If the cost of press passes and re-prints is factored in, the actual cost is many millions of pounds annually. GMG’s latest technology removes the unpredicatbility, and accelerates production cycles, improves quality, and reduces cost.
Once the ability to predict overprint behaviour is available, the next step will be for producers of packaging to eliminate any inks that are not needed. By letting brand owners eliminate colours within a job without changing its appearance, or compromising the brand identity, production costs will reduce. Currently the creation of this type of artwork is very expensive and is often created with trial and error methods. However, with GMG’s improved proofing, producing these colour separations will become easier to manage.
OpenColor gives users in the FMCG marketplace the ability to create more dynamic designs, while benefitting from accelerated production times.