Digital Magazine

Holograms continue to gain in converting applications.

The annual conference on holographic technology addresses a wide range of issues facing this industry today. This article presents a recap of some of the papers with an interest to the converting industry that were presented during the 1994 edition of Holo-pack/Holo-print, which was held in London, England, recently.

A wide range of topics centering around embossed holograms was presented during the 1994 Holo-pack/Holo-print Conference held in London, England, under the sponsorship of Pira International, Leatherhead, Surrey UK.

From holographic trends in flexible packaging to security issues to combining holograms and printing, the annual conference presented a roundup of global-holographic activity.

In a discussion of Adding Holographic Materials to Flexible Packaging, Alex E. Smith, marketing manger for Lawson Mardon Flexible in the UK, said holography should be an obvious contender for use in flexible packaging because it's eye catching, novel and has other beneficial characteristics, such as the difficulty of copying.

Despite these benefits, Smith said "there have been relatively few examples where holography has been used as an integral part of flexible packaging." Technical performance and cost implications were among the reasons cited for the limited use of holography in packaging.

"Flexible packaging is a large and highly competitive market," Smith said. "Individual-branded lines can involve hundreds of millions of units per annum. We're also seeing Eurobrands emerging in some markets and, in some cases, decisions on brands can be made worldwide. Most packaging is produced on high-speed conversion equipment and packaging machinery."

These factors mean that for the flexible-packaging converter and packager to be successful, they must be very efficient with their manufacturing processes. "Most conversion is carried out in widths between .8-m and 1.2-m wide," Smith said. "The widths used by the packer tends to be narrower. For instance, a typical crisp pack is around 270-mm wide. The converter will process several widths across the web. Depending on the application, one or more processes will be done, followed by slitting to provide the packer with the narrower material needed for the packaging machine."

Width is the significant factor. "When holographic materials were being produced on narrow reels 6-in. wide, they were of no use to the flexible-packaging industry," Smith said. "The widths we need are now available, and, in fact, we're now entering an era where the embossing widths will exceed the width of conversion and holography suppliers will be slitting down to provide narrow reels to us."

Materials are a factor. "The work-horse materials used by the flexible-packing industry are polypropylene, polyethylene, paper and aluminum foil, and they're often combined with a wide range of variations," he said. "To a lesser extent, polyester, polyamide or nylon, polyvinyl chloride, cellulose film and some of the less-common plastic films are used, but the volume is far smaller.

"Polyester and polyvinyl chloride were the traditional materials used by holographers, but more recently polypropylene has become available down to the ganges we use, and metallized paper is also available. Transfer technology is bringing other materials into the range being offered to us."

Smith issued a warning about the use of holographic materials for food packaging. "The legislation regarding the use of materials for food packaging is complex and will undoubtedly become more so as health and environmental pressures grow," he said. "Don't underestimate the amount of work that will be needed if you attempt to obtain approval for materials that aren't currently accepted. It will almost certainly be easier to change coatings, solvents, inks or additives that you're currently using if they don't have approval rather than attempting the time consuming and costly alternative of obtaining approval. This is an area where converters and materials suppliers can help as these are part of the problems we handle every day of the week."

In return, Smith said converters need help from the holographers. "We run our materials at speeds that are far in excess of your own processing speeds," he said. "We are familiar with control of coating weights, color consistency of inks and many of the other variables that affect our own processing and those of our customers.

"We don't understand the factors governing the replay of holographic images, the types of holographic images and the effect of display in different types of lights. We are beginning to understand what happens when we over-print the hologram to meet the marketing requirements of our customers.

"Much of the above seems to us to be a craft where learning is by experience rather than scientific principles, which we find puzzling as our own industry has moved away from this craft environment," Smith said.

Another factor is that converters "are very unsympathetic to anything that impairs our own efficient operations," he said. "Factors such as poor joins, uneven reel profile, surface-slip characteristics and the length of material on a reel may not be significant at slow running speeds. They can become critical on expensive converting equipment running at the speeds we need to maintain."

Smith said cost is "undoubtedly a deterrent" to hologram use in packaging. "I'm often asked what would be an acceptable cost, and I'm not sure I can answer this. Many innovations in recent years, such as metallized laminates for snacks, have involved a hefty increase in cost. More recently, on-pack promotions involving sophisticated-printing techniques have added costs. My own feeling is that marketing budgets are just about at the limits of acceptability when packaging costs are doubled. At this level, holograms are only considered for short-term promotional needs rather than as an ongoing requirement."

Smith had several suggestions on how more value could be put into holographic packaging, including:

* Better use of continuous designs, resulting in a better marriage between print and holograms.

* Introduction of moving holograms.

* Use of three-dimensional holograms.

* Registering print to the hologram.

"I would stress that any improvement of the hologram must not be at the expense of visual impact," Smith said.

"We have seen a gradual movement away from simple repetitive patterns towards more sophisticated designs, where the holographic features are being used for more than just a sparkle of light and color," Smith said. "Some of the criteria mentioned earlier are now being incorporated into design. The challenge must be to continue down this path, giving more value by improving the replay of holographic images under different lighting conditions while containing or reducing cost. If we can do this, I can see an increased demand for holography as one of the tools available to the flexible-packaging designer leader to a better future for both the holographer and the converter."

Wide-web embossing systems are the latest answer to the growing demand for holographic materials in the packaging section and in industrial-label converting, according to Alessandro Dondi, general manager of Diavy Tecnologie Olograf in Italy. He explained two systems MHT has developed for wide-web embossing systems. One is aimed at the packaging industry and processes transparent film, which is metallized after embossing. The second is designed for the manufacture of security labels and graphics, and it uses premetallized film.

"Material width and productivity directly determine end-product costs and are of tremendous importance to today's market, which is extremely sensitive to the price of flexible packaging," Dondi said. "The ability to adapt to different material types is also essential if a modern manufacturer is to win and hold a share in today's market, in which holographic material represents an added value compared to traditional materials with years of use behind them.

He said a good wide-web embossing system must be able to handle a wide range of materials, including polyvinyl chloride, oriented polypropylene, polyester, nylon and paper. "These materials differ greatly in the ease with which they can be embossed," Dondi said. "Some even require special pre-coating before embossing becomes possible. Wide-web embossing systems must be able to handle all these variables and the differing structures of the materials involved.

Peter Lowe, assistant director of the ICC Counterfeiting Intelligence Bureau in the UK, presented on overview on counterfeiting. Holograms have long been promoted as being effective in deterring counterfeiting.

"Counterfeiting kills innovation, products, jobs, companies and, even, people," Lowe said. "While to some this might sound overdramatic, it is unfortunately true."

Some of the counterfeiting exposed throughout the world in 1993 included a diverse range of products - high-performance automobiles, sun tan lotion, satellite decoders, super glue, washing powder and mozzarella cheese for pizzas. "The financial losses attributable to product counterfeiting, while difficult to estimate precisely, are enormous," Lowe said. "The computer-software industry estimates its global losses at $12 billion (US dollars) per year. The Motion Picture Export Association of America is said to lose US$2 billion annually." Other key counterfeiting areas include perfumes (US$70 million) and pharmaceuticals (US$100 million).

"These statistics are truly alarming and it's not difficult to see why product counterfeiting has been described as the greatest ongoing theft in the world," Lowe said.

Brian J. Monaghan, vice president of sales for Pennsylvania Pulp and Paper Co., discussed Interactive Graphics for Paper and Board. "Taking holographics to another dimension by adding conventional printing techniques can be overwhelming for some, but the results are fantastic," Monaghan said. "By taking a specific image of a hologram of any type and adding quality printing graphics in register to the hologram, powerful effects can be achieved. Add the mixture of translucent and opaque areas of printing and the end result is something unique to secure a product or catch the eye of a consumer."

A key consideration is deciding what substrate to use. "In today's advanced-holographic industry, many choices are available for holographic substrates," Monaghan said. "Just as important as the designing phase, choosing the correct substrate can make a world of difference. Each substrate has its own advantages and disadvantages."

Paper is currently the most popular choice, according to Monaghan. "Holographic paper is converter friendly," he said. "It's designed to be offset printable and react very similar to paper that printers use every day. Current holographic-appear embossers are running wide-web materials with large repeat cylinders."

A disadvantage of embossing onto paper is that it will shrink. "Although the shrinking of the hologram on the paper could be potentially devastating, paper seems to be consistent in shrinkage, which can be anticipated in the mastering phase," Monaghan said. "Paper is cost effective and gives modestly good holographic reproduction,"

Biaxially oriented polypropylene is the second most-popular choice for holograms. "This is one of the most economical substrates giving good holo-graphic reproduction," Monaghan said. "Current holographic embossers can emboss using cylinders up to 72-in. repeats. This would be more conducive to large runs because of the fairly large cost in plating such large cylinders." He said shrinkage of this film is minimized, although stretching can be a factor.

Polyester is also used, but its price of two to three times the cost of biaxially oriented polypropylene means it's used for smaller runs where "quality is the main factor and cost isn't as important," Monaghan said. "Holographic reproduction in polyester gives some of the best quality available, but it isn't converter friendly due to its difficulty in some printing process and because of static electricity."

Hot stamping of foil is another possibility. "High quality and exact registration are the advantages of stamping material," Monaghan said. "Interactive printing after foil standing can be very difficult if too much pressure is involved in the stamping into specific substrates.

"One of the most important factors in choosing a substrate is the optical-reproduction clarity," he said. "Different registration marks can be used for optical sheeting or optical registration for web printing. If the clarity of the registration mark isn't consistent, registration in printing or sheeting can suffer."

The effects of printing and converting in register to holograms are "incredible," according to Monaghan. "In the point-of-purchase field for packaging or displays, the object is to have the consumer to look at the product for two seconds. With holography and lithography, the change of increased sales are overwhelming."

The security-hologram industry in China has been growing quickly during the past eight years, according to a presentation by Xiangsu Zhang, associate professor of physics at Ziamen University in China. The first company producing embossed holograms in China was established in 1986. According to the Chinese Hologram Association, there are currently about 250 companies producing holograms in China.

Zhang cited the following reasons for such fast growth in the Chinese security-hologram industry:

* A large market for security holograms - In China, counterfeiting is so serious that most of the good Chinese products have counterfeits. Wine, clothes, food, medicine and electronic equipment is counterfeited. In 1990, the Beijing government organized a product-quality campaign to crack down on counterfeits. About 80% of the wines being marketed in Beijing were counterfeits. The embossed hologram was regarded as the most-effective weapon against counterfeits.

* Low-cost domestic technology and equipment - The investment to establish a hologram company using domestic technology and equipment is lower than many other types of investments. This allowed the establishment of many hologram companies in a short period.

* A helpful push from abroad - Several foreign companies have been coming to China to exhibit, propagate and sell their equipment, materials and techniques for making embossed holograms. Some foreign firms have established joint ventures with Chinese firms.

Zhang said although there are many hologram companies in China, only a small number are profitable. Reasons for the unsuccessful companies include bad management, poor or limited technology and too large an investment in transferring technology from abroad.

"The Chinese security-hologram industry is a new industry developed under the special circumstances in China," Zhang said. "Because it's new, it's unstable. Many new companies set up, and many old ones are (closed) every year. However, this doesn't stop the progress of the industry itself. Disciplines and legal restrictions in the industry are expected to be made."

Subscribe to PFFC's EClips Newsletter