6th Annual Technology Conference

Indian Habitat Centre, New Delhi, 24-26 November 1999

Developments in Packaging and Carton-making

M.S. Gadhok

Packaging is among the ten largest industries in the world. There are various packaging options like metal, glass, paper, plastics and a combination of these, but we will narrow down our survey to the cartons. Interestingly, in the paperboard segment, while cartons form a part of it, 60% of the paperboard segment is the corrugated boxes, and 70% of the metal comes from the beverages and food cans. Glass is shrinking. Interestingly, paperboard is the most easily recyclable, plastics is getting into that mould but it’s still a bit far away. Within paperboards, the metalised and the foil boards are getting replaced and this is where inks come in. The foil board is getting replaced by foil lookalike, and the lookalike comes from inks.

Packaging design is becoming the fifth P of marketing-after product, price, promotion and place. It’s the first impact on the consume., It’s a key instrument for differentiation, and is instrumental in the first buy. There have been major changes happening in packaging design in the last few years. I’ll share some of the information and how we are trying to relate that to branding. Second, there is increased relevance to the ad brands, especially in things like liquor, cigarettes which might get extended further. Whatever you want to communicate, packaging will increasingly become the only means of communication. Branding is very important for any consumer product. What is coming up today is the fact how you use your image to communicate the brand specifics and brand characteristics that you want to highlight. Quick turnaround is another thing that is emerging. A major revolution that is expected to occur now is with the digitised proofs, the digitised linkups.

Printing processes-What do we use for packaging? We’ve heard of offset, gravure, flexo. Offset is used when we have to get off very quickly-new launches, festival packs. Gravure is excellent for metallics, where you need gold and silver, and for long runs. That’s basically the way in which we decide on the technology. Offset can quickly get us to press, in terms of reproduction quality. However this is not entirely true, you can get pretty good quality in gravure as well as on flexo which is fast emerging as an option although it is going to take time to establish itself. . .

Online Document Finishing for Digital Printing

Ron Augustin

I sometimes get the impression that trends and tendencies are publicised in a way as if we printers and publishers are mere followers of these trends or to put it in another way, as if Indian printers and publishers have to follow their colleagues in the West at the very very high end, especially when we are speaking about taking on capital- intensive technologies. Most of the technological breakthroughs that have occurred in the last thirty years have been the result of an integration between printers and publishers on one hand and hardware manufacturers and software developers on the other.

In my view, technologies evolved because there was a necessity and demand for them in terms of higher quality, creativity and productivity, and not merely out of cost considerations. You have seen graphic designers and process bureaus getting into digital printing, you may see book publishers and booksellers getting into digital printing. But you may also soon see enterprises from completely different sectors of the industry getting into digital printing and even finishing.

Historically, in Europe the economics of the printing industry have forced binding and in a larger sense finishing, out of the pressroom and out of the printing house as well. So we have small and large enterprises which are completely independent of the printers and take on finishing work. In the past few years we have seen a lot of mergers in this sector and the emergence of larger, specialised enterprises in the finishing sector. We have also seen a great number of smaller companies which have had to struggle and a lot of binders slide into bankruptcy. Why? Mainly because of over-capacity in this sector or maybe because they have looked at their services a bit more rigidly. Logically, binders started to invest in digital printing equipment.

We see digital printing coming in as an integration with binding in a sector that may directly compete with printers and publishers as well. So, in summary, I feel that the survival of many companies will depend on their move towards integration. &&&&&Nearline finishing was the buzz at IPEX last year, which meant not really the physical distance to the machine, but certain digital data which can be gathered from prepress into the digital printing machine, and can be used in finishing like imposition and folding. . .

Converting Webs Online for Packaging

M.S. Gadhok

The important thing that we are looking at and what we have been moving towards, is offline versus inline.The focus is increasingly going to be towards how to sustain and support the high-speed packers with your packaging. That’s where the criticality comes in because we’re talking of 400-500 packs per minute, you need a flat, very precise product which can run at that speed. There will be slight variations, you’ll find the machines will be jamming up, there will be high wastages, and your products will be unacceptable. That’s where the highest end machines give the best packaging in terms of precision. All your technology has to be geared towards it.

Starting with offline and inline, in inline and offline you have printed sheets which are taken through a punching machine, which punches the product and provides the creases when you make a fold for a carton and since you have punched it, there will be some material that will be taken out which is called stripping, and then you have to bundle them. So there is a huge amount which can’t be handled manually, you have to bundle it and supply it. In inline you have the board that comes in reel form which ends up at the other end as a bundled pack. Inline again has two varieties-flatbed and rotary.

Dies are another area where lot of developments have taken place. Traditionally, we were using wooden dies; There are two alternatives that have come in-one is plastic fibreglass sandwiched between plastic sheets and the other is plastic sandwiched between two steel plates, so that it is free from humidity and temperature variations. As compared to wooden dies the life of these dies is significantly enhanced. They are expensive but their life is also much higher. Let’s move on to inline conversion. Here, you have a flatbed punching press linked to a gravure press. Next is the rotary concept which we are using and have found a lot of benefits with it. Against the flatbed cylinders here you find rotary cylinders. They are again very precise cylinders, in fact the gap between them has to be set to as low as 3 microns. That’s the kind of precision you need to have right across the length. These dies are very expensive, in fact a set of these dies is valued at more than Rs 1 crore. It is more expensive than most of the machines, but the advantage with this is that the life of this die is maybe 50 times more than a typical punching die. Therefore, in the long run, the cost gets amortised very well.

Choice of rotary versus flatbed -- a rotary die is inflexible, fixed and expensive. It can run, can give you very high speeds, and very consistent quality. A flatbed die is flexible, cheaper, but limits the speeds on an online press. An online press will get limited to a speed of about 150 metres per minute whereas the same press can run at a speed of about 250 metres per minute with a rotary die-cutting system.

Types of packers - we have packers ranging from 150 packs to 700 packs per minute. At ITC we’re still at about 400-500 packs but we are moving towards high-speed packers. Even for 400 packs per minute, you need a very precise product, you cannot do with a normal crease which is shallow or varied.

Our experience - Once we changed from flatbed to rotary dies, the productivity at the cigarette factory went up from 4 million to 5 million in about 3-4 months.

Inks provide a key value addition to foil lookalike, foil stamping, foil effect and metallics. Inks is a very touchy subject, the solvents you use are critical. Avoidance of heavy metal is becoming critical even in offset inks as well as in gravure inks from an environmental point of view. . .

Narrow Web Flexo

Sudhir Samant

The basic areas I am going to cover are the narrow web flexo machines, the market and the inking systems and the anilox rollers. With flexo many processes can be handled inline: first and foremost is the printing. You can start with 2-colour printing and go upto 14-colour printing, you can do backside printing by putting the reverse webturn bar, you can do hotfoil stamping. A new development was introduced at the recent Labelexpo, which is called coldfoil transfer. You can do lamination, UV varnishing-either full or spot-converting, that’s again a diecutting feature, coding and many more. A small comparison between flexo and letterpress taking into consideration a flatbed letterpress machine; the rotary letterpress machines in India are predominantly used in the lamitube business. If you see the comparisons, the letterpress machines come with lesser speeds, there are not many drying systems around. Flexo presses can operate at higher speeds-500 + feet per minute-it’s good for medium-to long-run jobs, the dies used are normally imported rotary dies. Flexo is a fast-growing technology for its acceptable printing quality. It is not the machine but the technology which is gaining popularity. The plate is getting thinner-it used to be 2 mm in thickness, now it is available in 1.7, 1.4 or 0.4 mm. Thinner plates have less dot gain and higher quality. The price is affordable compared to letterpress rotary where you have to have a UV rotary and the cost is high.

Some comparisons between flexo versus offset. This is again related to packaging-, we’re not talking about commercial printing. There is better colour consistency in flexo because there is no ink-water balance, you can print on any substrate; after each print station there is a hot air or IR dryer which dries the print completely before it goes to the second station. Printing can be done on any substrate-metalised paper, films, foils, paper. The costs incurred are lower compared to offset because you have to have too many units if you do offline printing. If you do inline printing, considering the repeat cost of the offset unit, the dampening systems and the inking trays of the 20 x 30" rollers, the project cost is very high.

As far as the market trends are concerned, there is a continuous growth of pressure-sensitive labels-these are generally supplied in sheet form, but the end-users, the oil or the cosmetic industry, are applying the label applicators which means that you can’t supply them in the sheet form, they have to have a roll. As I said, there is worldwide acceptance of flexo technology, there is consolidation of the label converter, film labels are taking shape, that is, supported film.

The inking system is fairly simple comprising one, two or three rollers, depending on the technology, size and cost of the machine, and what it is meant for. The simple machines, that is, the central impression type of machines, normally use the 3- roller system, and are good for linework. The metering rolls supply the ink to the anilox rolls which are normally chrome and go onward to the plates and the paper passes through between the plate and the impression cylinder. The pressure between the metering rollers and the anilox rollers determines the amount of ink that you are transferring to the chrome anilox rollers. A problem in the metering system is the possibility of deflection. The higher the printing speed, the higher the hydraulic pumping action and the higher the density, the higher the dot gain. The other system which is used is that of anilox rollers with the doctor blades. After the ink is transferred, the doctor blades remove the excess inks from the ceramic anilox rolls. You can’t use the chrome anilox rolls while using the doctor blades. In order to eliminate the deficiency in the metering system, the doctor blade system has been introduced and has been used widely in various new-generation flexo presses. The doctor blade wipes out the excess ink which is again recirculated back to the tank, filtered out and pumped up again. This gives you precise quality. Among the disadvantages of positive doctoring, hydraulic pressure is deflected and there is a chance of getting more ink than required. The advantage of reverse angle doctoring is that it basically cuts down excess ink.

As far as the ceramic anilox rolls are concerned, they are considered the heart of the flexo presses and determine the exact amount of ink you are transferring to the substrate. . .

Thread Sealing and Sewing for Books and Periodicals

Jurgen Rothe

If we compare books prepared through book sewing and those that are made through the perfect binding technique, we find that the strings and the opening of the books are much better in the book sewing technique, and these strings were responsible for the development of the thread sealing technology. The thread sealing machine can be attached to any kind of folding machine, which can perform at any speed upto 200 metres per minute. A continuous stream of specially twisted thread is being stitched into the signature, and the end of the thread is being melted. Then we go onto the sealing machine. The sealing procedure is done before we do the last fold. For the sealing procedure we need a special thread and the thread is about 50% cotton and 50% nylon. This thread is also available in India and there is a German supplier in New Delhi.

A conveyor chain transport the thread and there is a gear box in which we stitch the thread through the signature. Then the thread ends are sealed with a heating device.Thread sealing costs the same as perfect binding, only the price of the thread has to be calculated. In Asia, more and more binderies are going in for the thread sealing technology. In the last four years many binders worldwide have been going for thread- sealing machines. The shredding knives cut the thread, and by means of needles we push the thread through the plate into the paper. The machine is also controlled by an electronic device. So it’s a very fast setup-to go from the maximum to the minimum size you need only five minutes because all the other things are done by the machine. The machine will calculates how many steps will be required for the responsible length of the sheets.

Through book sewing you save labour costs and time because this is one procedure that is attached with the folding machine. Behind the thread sealer the last fold is made by either a separate folding unit or an attached folding unit. After thread sealing you have to make one fold. The thread sealing unit can be placed anywhere in the folding machine-I can make one, two, or three folds, it makes no difference, is concenred and as far as the speed, with the fastest machine we can go upto speeds that are allowed by the folding machines. We only have to give the length of the paper to the computer and the computer will give us all the other information. The sealing temperature is around 300 degrees centigrade, and there is also a display to see whether all the stitches are done. . .

Developments in Inks and Surface Coatings

Z.A. Lakdawala

I will be talking about recent developments in printing inks and surface coatings. Printing inks as we know it, is a very vast field to talk about. So I will concentrate on recent developments in publication printing inks, particularly those used in the lithographic printing process. In India, publication printing is only being done though the web offset printing process. However, in the Western world gravure and flexography are being used to a certain extent.

As far as the technology of heatset inks is concerned, recent upgradations have been done in two areas. The first development is that of the heatset ink vehicle-ink vehicle in common parlance means ink varnish or ink medium. The modern heatset ink vehicle consists of high molecular weight visco-elastic resins. The selection of these resins are of various types. Depending on what type of ink formulation the ink technician would like to do, he selects the right grade of visco-elastic resins.

The next component in the heatset ink vehicle is the hybrid hydrocarbon resin. These resins in a very thin frame of print, throw the solvent out which is used in the PID-Printing Ink Dissilet. The function of this resin is to drive out the solvent in a thin film when it comes to the paper and goes into the oven at a minimum web temperature of 120 degrees centigrade.

The next technological upgradation in the field of printing inks for the first time in India developed by an Indian ink manufacturing company is that of flush-based pigments. What is a flush-based pigment? A flush pigment is a highly concentrated pigment paste in a selected ink vehicle.

What are the advantages of flush pigments? The advantages are that as compared to dry pigments-the method in which most of the inks are being which manufactured in India and some other countries, where dry pigments are being ground into the ink vehicle-the degree and the quality of the pigment dispersion in the flush- based pigments is distinctly better, more efficient and absolutely uniform.

Now we come to the news black ink. A conventional news black ink is designed for high speed, and continuous printing presses in order to meet the tight schedule of newspaper production. These inks should have good fast-setting properties, good printability, and a desired level of print density. One main ingredient used in the conventional news black inks is high structured carbon black, which is locally available. You need to disperse the carbon black uniformly as fast as possible, for which some wetting and disposing agents are used. The ink should also have a good flow and should be free from misting and flying for which some additives are being incorporated to improve the flow and anti-mist properties. The only negative factor for the conventional news black ink is that it has very low rub resistance properties and the print has got a charcoal-like effect. Though the cost of the ink in relation to the newspaper is below 5%, but due to the large volumes of ink required, the cost is a very important factor.

I will now take up low-rub news black inks. like conventional news blacks inks, these inks are also a requirement to maintain the quality and standard of press performance and its usage depends on the type of machine and the market requirements. Some of the ingredients of low-rub news black inks are, low structure carbon black as compared to conventional news black, which is almost three times costlier than the high structure carbon black. Low structure carbon blacks are not manufactured in our country, they are imported because of which they are costlier. Another development mainly in the US, is that for the use of oil-based products, news black inks are being made.

Then we come to the coldset news inks. The latest coldset web colours or coldset black inks are being manufactured by the flush pigment, vegetable oil-based vehicles. The latest change in the coldset colours is that mineral oils have been replaced now by vegetable oils. . .

High Speed Saddle Stitching for Commercial and Publication Printing

Salich Cibic

My presentation will be on postpress saddle stitching as it preva ils today. Is high speed saddle stitching desirable? Saddle stitching is simply the art of inserting signatures on top of other signatures over a saddle and driving wire stitches, through a gathered piece backbone, holding a finishing product in your hands.

A modern, up to date saddle stitcher should have the possibility of 3-up production. I know of only one supplier who can do the job in the trimmer, not outside of the trimmer, so that you can do the same job in a third of the time that you are using today. Hole punching-you as a specialist in finishing must be able to do that in a trimmer while you cut and not doing it outside because that again costs a lot of time. It should be easy to adjust the transfer table which must provide an accurate and reliable product transfer to the final trimming position. The whole equipment should be designed at a comfortable working height ergonomically. There should be central air supply, for blast air and vacuum flow must be standard, Newest control units on SPS basis with diagnosis of errors is also a must. A central control panel with display and a consequent modular display is absolutely required. Generally speaking, these and other requirements are part of, and aid in, an optimal net output. Yes, it is desirable to have a high speed saddle stitcher, but we can never forget that each product itself tells us finally where the limits are. The laws of physics are also playing a useful role in this game by thinking on all these possibilities and difficulties which are absolutely normal and which you fine daily in your production process.

Such a product can create for me and a lot of our colleagues, the formula for high-speed-if we add all the items that I mentioned before-is the following: a high- speed machine must be equipped with versatile feeders, fastest makeready, as many options or controls as possible, all these should be combined in one tool called a saddle stitcher, should be tailored to your progamme, to your range of products. It is easy to opt for high speed, but you must ask first what you have to do in high speed, and with what. And then you should go to the manufacturer who will sit with you and talk about each individual case. There we can create high speed; if you buy a fast machine of 20,000 per hour, that doesn’t mean that you have to produce each of your products at 18-19,000. Therefore, you must get your queries sorted out individually with the manufacturers or their agents, that’s the only way to achieve high speed, and again, high speed means finally net output depending on the nature of the product you have to produce. The saddle stitching world is interesting and speedy if you use the right instruments focussed to your bussiness. If you have the right machine you will achieve for each of your products the maximum possible speed . . .

Wide, Ultra-wide and New Inkjet Technologies

Naresh Khanna

In the wide-format industry, there are varying estimates about its rate of growth. There was a figure of Rs 900 crores until about two years ago. In the last year and a half or so, since hoardings have been banned, the money that was to go into advertising and publicity and was meant for ultra-wide signage, went into bus shelters as that money could not be entirely spent on store signage-that kind of retail space is not yet available.

This is why there has been an explosion of the 48-inch, 54-inch and the 60-inch inkjet printers. There are varying estimates as to how many of these machines sell in a year. I believe that the market for these kind of machines is 200 in a year, which still represents a considerable growth. At the low end these machines go into CAD/CAM, not into signage. Many of the inkjets-specially the piezo-based inkjets, the 6-colour machines-go into signage.

The key issue in outdoor signage is, resistance to ultra-violet light. The resolution issue, I must point out, is not such a big issue. Resolution is really needed according to the distance of viewing and although we as printers and digital prepress professionals are obsessed with the resolution issue, very high resolutions are not required. However, printers are being offered now with resolutions as high as 720 dpi.

There are varying estimates on the amount of signage that is printed outside India and imported. The Indian ultra-wide printers are still not able to meet the needs of outdoor advertising in the ultra-wide sector. There is considerable interest among international manufacturers in coming into India to supply Indian advertisers with ultr- wide signage.

Most of the wide and ultra-wide printers use either thermal technology or thermal piezo technology. In the piezo technology, there is the drop-on-demand technology and the continuous flow technology. The continuous flow technology is similar to what you see in the digital proofers like the Iris inkjet. What happens in this is that the piezo canon is firing the ink continuously, and where the ink is not needed, it is deflected electrically. This is as opposed to the drop-on-demand technology, where you fire the ink only when it’s needed. The argument in favour of continuous flow is that the ink is cheaper, the machines are faster, and they do not have as much problem with missing areas and streaks.

Inkjet itself, to some people is a very exciting technology. Somebody earlier mentioned online, digital printing to either a packaging machine or a newspaper machine. Actually, this kind of thing is being done by inkjet. Even on the online kind of devices, the inkjets are being widened, the resolutions are being increased. You are very soon going to be able to produce an entire newspaper page, running on a web, with inkjet. That means, in a 16-page newspaper, 15 pages will be done in the normal offset fashion but the 16th page will change with each edition. This is definitely on the cards for inkjets, and the people who are developing inkjet are extremely optimistic and aggressive.

In Israel for example, the feeling among some of the inkjet terchnologists is, that inkjet will rule the world. As you know, some of the other inkjet applications are in wide-format printers for entire signatures, as people get ready for 8-page film or computer-to-plate. Then there is high-speed mono-colour printing for newspaper webs and books.

The thing to remember about inkjet is, the worse the paper, the better the quality of the printing. There are several companies that are active in the Indian packaging market as far as inkjet. The issues about which the inkjet professionals are excited about are the possibility of increasing resolution, the use of different kinds of inks-they are hoping to use UV curable inks.

Greyscale piezo is another area of great interest. That means, you will have eight levels for every drop, and this represents a tremendous possibility as far as photographic reproduction. The first sectors to benefit from the use of UV inks will be plastic cards, CD Roms and variable data applications, and because of the higher resolutions, and the combination of UV and oil-based inks, you will be able to print on packaging, and will be able to do packaging on rough board and recycled board. And there is also a possibility that you can do packaging on films, you’ll have the kind of inks that will dry on non-porous substrates and on coated cartons.

There are some people who think that within two years you will be able to print unit packaging by inkjet directly on packaging, which is about two years down the line. The other possibility for Greyscale piezo and UV cuable inks is that they can be used in textile printing and also in photo labs, for art quality prints. This technology also seems to offer the possibility of indoor signage at very high resolutions and for use at photographic exhibitions and prints, using greyscale colour inkjets . . .

CIP3 in Print Finishing - Achievements and Prospects

Lawrence Wallis

CIP3 is a process for turning printing in a computer-integrated manufacturing process. CIP3 stands for "Cooperation for Integration of Prepress, Press and Postpress". Computer integration of prepress is taking place quickly in my country.

There are several reasons for the low level of activity in the postpress area. Very few finishing machines are computer-controlled. Very few finishing machines incorporate motorised setups, they have manual setups. Both these conditions are essential for the implementation of CIP3, you must be looking for machines which are more automatic, more computer-controlled with motorised setups, otherwise we cannot implement CIP3. Most vendors in the postpress area do not perceive a competitive advantage in adding computer control to their print finishing equipment. Finishing machines generally run slower than presses, accordingly the ratio of setup times to run times, make it difficult to justify automation of makeready on economic grounds. As demand for shorter runs and faster turnaround time grows, the pressure to automate postpress setups will increase. As runs get shorter, as the markets demand faster delivery of jobs, so the pressure to automate postpress will increase.

Compucut is the software provided to automate guillotine. Compucut runs on a PC under Windows with 8 MB of RAM, 10 MB hard disk, a 17-inch colour monitor, a mouse, and a serial interface for online transfer to the machine, you can also do it by means of a smart card or PMS card. The whole box, the sofware and the hardware, is known as the Compubox. There are three ways in which we can feed this information into a guillotine. The Compucut can receive data direct from the prepress system in a CIP3 PPF file for direct use on the guillotine by online transfer. The imposition is the source of all the information or most of the information that we need in print finishing, the imposition scheme is the key. So, one way is to transfer the data from the prepress direct into the Compubox. A cutting programme can be prepared at the Compubox for transmission directly into the guillotine. Another way is that we can prepare cutting programmes offline at the Compubox and write them to a smart card which we can then take to the guillotine which has a reader to decode that card. There are only three moving parts on a guillotine. One is the knife or the blade, the other is the back gauge, and the third is the clamp.

CIP3 transfer of data avoids the need to enter fresh parameters and therefore aids accuracy; we enter the data once, preferably at the prepress stage and we use that throughout the printing and print finishing processes. The printed sheets do not need to be measured at the guillotine because you’ve got all the information in the PPF file. It can be verified with the CIP3 data that’s to hand. . .