Special format labels have been available for many years now, appearing in a variety of different industries most notably chemical, cosmetic,

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2 Special format labels have been available for many years now, appearing in a variety of different industries most notably chemical, cosmetic, healthcare and pharmaceutical. Dual and multi layer labels have been used for applications where the product space available has been inadequate to present the required information on a standard label format. Whether driven by marketing desire or regulatory needs, a label which has more than one layer significantly increases the label presentation area. Dual or multi layer labels are commonly known as leaflet labels, booklet labels or fix-a-form labels and are constituted from a single or multi page leaflet incorporated on top of a self adhesive label with another self adhesive cover. From a pharmaceutical industry perspective, multi page labels have been especially noticeable as the strict regulatory control from the likes of the FDA and MHRA has increased the need for more product information and in many cases in multiple languages. Where historically a single layer paper label has been deemed adequate, it is now not unusual to find special peelable labels which are more like mini booklets in some cases including up to 40 internal pages behind a sealable cover label. Leaflet labels are commonly found on a variety of pharmaceutical products including over the counter (OTC) medicines such a cough syrups; prescription based solid dose products, clinical trial products and also unit dose injectables. The production of these products requires the application of such leaflet labels onto glass and plastic bottles, square pots, vials and even ampoules. Such booklet or leaflet labels are of great benefit to manufacturers in providing much needed extra space for product information especially when they can - in theory - be applied to existing products using standard existing automated label application technology. Another significant benefit is that a multi page leaflet label can replace the requirement for a separate outsert booklet (US pharmaceutical applications) or a product carton, thus saving considerable cost and packaging time. In practice however, these labels can cause production problems for a good number of automatic application systems, as their initial design did not consider the use of anything other than a single ply label. So what are the problems? In the first instance we shall consider a standard reel of paper labels. The reel might be mm in diameter and contain several thousand labels. The labels are die cut with radiussed corners. They are lightweight, flexible and are only a few microns in thickness. It is also worth noting that such labels will have a clear, level area for lot, batch and expiry information which will be printed by coding system as part of the application process. Compare this to a similar sized reel of leaflet or multi layer labels. The same diameter reel will contain only a few hundred labels; the labels are relatively heavy, inflexible and can be several millimetres thick. In addition to this, leaflet labels have been designed specifically to allow the product user to open them, this requires that the label cover layer adhesive is nonpermanent and forms a relatively weak bond. Taking each feature in turn we consider the quantity issue. For example; a labeller operating in a production line at 100 bottles per minute will continue for 50 minutes with 5000 labels. If the production is changed to leaflet labels at the same speed, it is quite possible the label reel will only hold 1000 labels, giving the operator just 10 minutes of production between label reel changes. This smaller reel capacity causes significantly lower line efficiencies, especially if buffer feeding systems are not used on either side of the labelling system. It is possible in some instances to

3 use larger diameter label reels with larger capacities but these can be problematic for the operators if they are not handled very carefully the label cores may fall out and render the reel useless. dispensing phase. The labels may effectively be required to move though a series of tight turns as they negotiate these rollers. Normally this is not a major problem as The next potential issue is the label thicknesses. As mentioned before, a standard paper or polymer based label is a fraction of a millimetre in thickness whereas a booklet label may be several millimetres thick. A typical labeller will rely on the use of a fork style sensor or even a microswitch system to measure the distances between the labels on the carrier paper and hence allow accurate control of the label steps as they are dispensed onto the product. Such sensors are also used to recognise and signal when the label reel has run out. Fork sensors by their very nature have a limited gap size which is often smaller than the label thickness so alternatives must be found. Such untested non-standard items may cause initial set up and control issues and also introduce untried and hence unknown reliability factors. Label thickness may also affect the way the labeller is able to drive the labels towards the product. Many label dispensing systems use a nip roller system to push and pull the labels; this works very well if the labels are very thin as the float required in the nip roller system is minimal. With leaflet labels the difference between the label thickness and the backing paper is significant, this means that the floating roller system must cope with big steps between the label and backing paper as the labels pass through. This causes unreliable feeding, especially at elevated speeds and in the long term adds extra loading and premature wear to the drive system. This type of positive drive is also quite likely to force the leaflet labels to open up within the dispenser the cover layer of the label is designed to be peelable by the end user and hence uses a low tack adhesive; unfortunately this is also peelable by the applicator. Along with the additional label thickness come significant rigidity and material memory. Many label applicators feature a relatively complex series of rollers to control the movement of the labels through the standard labels are flexible. When the same is attempted with leaflet labels, the labels have a significant tendency to delaminate from the carrier web. This basically means that the web material is flexible and may form a curve around each roller easily whereas the label does not want to follow and peels away from its carrier within the labelling system. Once again this causes mechanical jamming and additional ongoing maintenance. The label material memory is also something to watch for, especially if the leaflet label is being applied to a square or rectangular product which has small radius corners. Although many leaflet labels are designed with some flexibility to allow application onto round products, the material memory when stretched around the corners of a square product may well cause the label cover piece to spring open even after the label has been applied effectively and passed by quality controls. Once again the low tack adhesive on the label cover does not help this situation because it sometimes cannot overcome the force generated by the materials memory. On new labelling systems during machine testing it is possible to observe these labels spring open which is not something the applicator can overcome and must be resolved with the label manufacturer.

4 overprint area which is very important for contact printers such as hot foil or thermal transfer technologies. A thick leaflet label cannot be overprinted onto the leaflet portion as this gives inconsistent results so the overprint code must be positioned onto the trailing edge of the label where it is flat and single layered. It is critical this area is large enough for the required text but when using a thermal transfer coding system the print head must engage the label vertically to allow enough run in to the coding phase. It is important that the coder print head will retract far enough from the print surface between codes to allow the thick booklet section to pass with damage to the coder or the label. With multi layer labels here to stay and their usage likely to increase, selecting label application systems that can cope with large variations in label thicknesses without any serious modification work is a high priority. So what should manufacturers look for to minimise the risk? The weight of leaflet labels is again another area that may cause difficulties. It is possible some leaflet labels fall open under their own weight while in position on a label dispenser during machine start up generally these labels can be closed again during the labelling phase but this is not to be relied upon as the application tolerance is not good. The application tolerance problem is compounded further if a flag and wrap style of application is used. In this case the label is applied onto one side of a product and dispensed so that it looks like a flag, the system will then wrap the label around the product within a side belt applicator system or similar. When heavy leaflet labels are applied in this way they have a tendency to sag before they are wrapped which may causes label creasing and a skewed application. The label overprint must also be considered. As mentioned above, standard labels have a flat clear One of the key factors in meeting this is the design of the label drive. Ideally the system should not drive the backing material until the label has already been removed from the web; this will ensure the labels do not open up during the process and will avoid damage to the label finish. Newman Labelling Systems achieve this by the use of a drive roller system which controls the label backing paper only, leaving the labels untouched on the carrier web until the point of application onto the product. Another important means of identifying a system that can genuinely handle heavy, inflexible labels is the label path; the shorter and simpler the better! Ideally the label web path from the reel unwinder to the applicator plate should be straight and unhindered by rollers or drive points to reduce the risk of label damage or peeling open systems with a complex series of tightly located rollers should be avoided. A straight label arm offers the ideal solution to this but care must be taken to offer adequate support to the heavy label web.

5 Good access to the label dispensing area should also be considered; a clear area with plenty of space for ancilliary equipment such as coders, sensors and cameras is important, especially if these items have to be adjusted regularly or even changed over to accommodate the leaflet labels. Special sensors in tight access areas should also be avoided as it may not be possible to change them as needed. Newman Labelling Systems, established in 1943, is a leading supplier of specialist pharmaceutical labelling systems. Customers include major global pharmaceutical manufacturers as well as many smaller biotech companies and locally-based manufacturers throughout the world. For more information please go to The system must also have robust control throughout the application phase to ensure the best possible placement accuracy of the label. For booklet labels applied onto round products, the flag and wrap method of application should be avoided. It is much better that the label dispensing is synchronised with the label application to minimise label sagging and ensure the application tolerance is kept to a minimum. The line efficiency may be maintained or improved by the use of system infeed and outfeed buffer tables which will allow the rest of the production line to function during the high frequency label reel changes. With leaflet labels offering real advantages to the manufacturer, we can expect increased usage over the coming years. But you cannot automatically expect your existing label application methods to cope with the demands they place on machinery, in terms of line efficiency, quality application and increased maintenance, especially if you haven t purchased at the quality end of the market. Well designed and manufactured labelling systems should not find the majority of leaflet labels an issue as they have been designed to accommodate label diversity through a short label path and appropriate label drive design.