Significance of consumables
in newspaper printing
In newspaper printing, alongwith other consumables, the performance of the inks plays a vital role in achieving substantial economy in the overall production cost. SS Kulkarni, general manager, Technical at Micro Inks | Huber Group describes the phenomenon in this regard since the inception of printing process.
S S Kulkarni and Sunil Jadli during Printpack India 2011 in New Delhi
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One of the most important events for the world that took place during the Tang (618-907) dynasty was the invention of printing, sometime between the 4th and 7th century AD. It began as blocks cut from wood used to print textiles and then used to reproduce short Buddhist religious texts that were carried as charms by believers. Later long scrolls and books were produced, first by wood-block printing and then, beginning in the 11th century, by using movable type. Inexpensive printed books became widely available in China during the Song (960-1279) dynasty. Since then the printing has undergone tremendous changes and has evolved with many printing processes starting from simple letter press block printing through screen printing, offset, gravure, flexography, intaglio and now even digital printing. It involves lots of mechanics and electronics.
The history of newspapers begins with the handwritten sheets covering news and events, posted daily in the public places of ancient Rome. However, the first printed newspaper was produced in China during the Tang dynasty (AD 618-907).
The main function of the newspapers is to report news. However, many newspapers publish the expertise on various subjects like sports, arts and entertainment, education, finance and investments, etc. Daily general circulation of newspapers averages about 36 pages during the week and more than 100 pages for the weekend edition. Commercial advertising takes up about two third of both weekday and weekend editions, and news and features fill the remaining third. This is largely because rather than the selling price of the newspaper, the main source of income for most of the newspapers is the revenue from advertisements.
Production of Newspapers
Most newspapers are printed on grainy, lightweight paper, called newsprint, which comes generally in one of two sizes. Broadsheet newspaper pages measure 33 cm by 55 cm (13 in by 21.5 in). The pages of tabloid newspapers measure about 25 cm by 37 cm (10 in by 14.5 in). The staff of a large newspaper works under the constant pressure of meeting the deadlines to offer the latest news and events to readers. Reporters, photographers, artists, and editors compile articles and graphics sometimes in just a few hours. Page designers assemble articles, photos, illustrations, advertisements, and eye-catching headlines into page layouts, and then rush their work to the printer. Printing technicians may work through the night operating printing presses that can churn out more than 80,000 copies per hour. And this is where the crucial role of the suppliers of various consumables to newspaper printing begins.
| Cost structure of the different consumables |
| The approximate cost structure of the different consumables required in offset printing is as given below: |
| Consumables | Cost |
| Papers | 73% |
| Plates | 14% |
| Blankets | 07% |
| Inks | 03% |
| Fount concentrates | 01% |
| Others | 02% |
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There are mainly two types of print runs in newspaper production. One is very long run, which prints over several lakhs of copies at a stretch. In second type, several small editions of thousands of copies are printed in a total print run of several lakhs of copies. In first case unless the situation demands, the machine need not be stopped till the completion of job. However, the uncoated stock used in newspaper production which normally contains the loose fluff, adheres to the blanket, and keeps on accumulating. This in turn deteriorates the print quality, and hence it becomes necessary to stop the machine intermittently, to clean up the blankets. In second case, the machine needs to be stopped several times, for changing the plates for various editions. When the machine is stopped and restarted after cleaning the blankets, or after changing the plates, whatever may be the case, it takes few seconds to achieve the same print results, as it was prior to stopping the machine. In these few seconds, few hundreds of copies are wasted resulting into the increment in the cost of the job. In both the cases, the performance of the inks plays a vital role in achieving the substantial reduction in cost.
Though the printing technology has emerged out as one of the branches of the technology, nonetheless, two consumables remain constant – substrates and inks, without which printing is not possible.
Consumables
Inspite of many changes and evolvement of various raw materials, the basic composition of inks – pigments, binders, solvents and additives has not changed. However, these materials have changed quite a lot in their respective technologies. pigments have changed from natural organic and inorganic to mainly synthetic organic, binders from vegetable oils to synthetic resins and numerous types of additives to get that something ‘extra’.
The composition for the inks for newspaper printing process is same and consists of pigments, binders, vegetable and petroleum oils, solvents and additives.
After manufacturing, the inks are tested for various parameters like dispersion, viscosity, tack, setting and drying, shade and strength and also for the functional properties like rub resistance. The formulation of printing inks starts from the knowledge and selection of key raw materials – pigments and resins, by the R&D chemists.
At Micro Inks
Micro Inks, due to its backward integration in resins and pigments, R&D starts right from these raw materials in the laboratories equipped with modern analytical and testing instruments. This is further supported by the process development carried out in the state-of-the-art manufacturing plants. These activities at Micro Inks are carried out in its EOU plant located in GIDC-Vapi. Well equipped ink development laboratories are under the plants located at Silvassa and Daman.
With the latest ‘!NKredible printing-ink technology’, MICRO - HUBER offers ‘GOOD NEWS’ series of cold set process colours, for newspaper printing. These are based on new generation resin technology, which helps to achieve the quicker than quickest ink water balance, resulting into faster restoring of print quality, at restart of the machine after every stoppage. Unique varnish formulation, based on these meticulously designed resins employed in GOOD NEWS inks, giving additional lubrication helps to minimize the fluff accumulation on the blankets and thereby reducing the frequency of cleaning them during the long run jobs. Reduced stoppages in long run jobs and achievement of fastest ink water balance helps to reduce number of waste copies. It can be well estimated that though the cost of the inks is less than 5%, but, since the cost of the paper is highest of the total cost of the consumables, reduction in printed waste at every restart, can help to achieve substantial reduction in cost of printing. That is why it has been experienced that, ‘GOOD NEWS’ inks though little higher priced, are not expensive.
Three varieties viz. PREMIUM, INTENSIVE and HIGH SPEED are made available confirming to the colour values as per ISO 2846 – 2 standard, to cater the various printing needs.
Process Standardisation
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Offset printing process though complex is a highly scientific process. By adopting the process of standardization not only quality consistency is maintained, but in long term it also helps for overall cost reduction. Printing ink is one of the consumables and hence is a part of this process. Apart from proper selection of consumables like inks and newsprints, monitoring ink deposition by way of controlling print density is essential. In any process apparent cost is often decisive and consumables chosen based on this can lead to heavy losses. Ink optimization, GCR/UCR/UCA and other such pre press soft wares certainly have promising feature and can be used very effectively to avoid certain problems during and post printing. SWOP, IFRA, ISO are the various standards which can be adopted for the total control over the entire printing process right from designing through pre press to consumables and the print quality. However, these should be adopted fully rather than just some part of it. Process of standardization is continuous process. Print quality should be evaluated constantly by measuring the parameters using proper instruments like spectrodensitometer. Deviation in the final readings should be controlled by rechecking all the parameters of the entire process. This of course can be done only after establishing the total process standardization. Micro Inks has been extending its cooperation in this process by recommending the right grade of inks meeting to certain standards like ISO 2846 and also extending the technical service support at the time of test chart printing to meet the standards laid down by IFRA or ISO.
The difference in the cost of black and CMY colours is fairly large only in case of news inks. News inks are used for printing absorbent stocks like SNP. Since the stock is too absorbent, inks do not print with glossy finish. Moreover, readability is the prime requirement in case of newspapers printing. Glossy inks often hamper the readability due to the glare from the text. Considering this, the pigments used for producing news black ink are relatively cheaper than CMY and are also cheaper than pigments used in producing black ink for other processes like sheetfed or heatset. This makes news black inks less costly than the news colours. More use of colours and less of black for four colour brown/black or shadow areas reproduction has commercial and technical disadvantages. Higher ink coverage often leads to problems during and/or after printing like ink accumulation on guide rollers/turner bars, set off, rub off and slower drying. Printers are forced to print with high ink coverage because advertisers demand richness in colour and often compare the results of the one printing process with the other. Every printing process has its own advantages and limitations. Ignoring the limitations of one printing process the results similar to other printing process are demanded from the printers and many times printers succumb to this pressure.
There is a difference between Soya inks and non VOC inks. As per international norms to qualify any inks to be called or labelled as Soya ink, it should contain 28% (Roughly – figure may vary) of Soya oil. Mineral oils which are required to meet the physical parameters like tack and viscosity are often used in addition to Soya oil. This means the product labelled as Soya oil may not be - and most of the time is not free from mineral oils. Mineral oils are VOC (Volatile Organic Compound), and hence the ink labelled as Soya oil may not free from VOC. As against this VOC free inks do not contain mineral oils and are based only on vegetable oils. However, VOC free inks are more expensive. The difference in cost of VOC free cold set black and conventional cold set black ink is much higher than the colour inks.
As a social commitment, the raw materials used for news inks are non toxic in nature. To reduce the dependency on non renewable petroleum oils and to help the printers to print ‘GREEN’ Micro-Huber has developed and established the products which ‘do not contain petrolium oils’ and are based on renewable and eco friendly vegetable derivatives. Micro Inks has also installed a state-of-the-art water treatment plant and has invested heavily on incinerators as a part of waste management system at EOU plant located in Vapi.
Ultimately, it depends on newspaper printers how they select their consumables, especially what sort of inks they use to make the newspaper printing economical without compromising on quality.
