Selecting paperboard for packaging
- CD covers
- MC inserts, audio cassettes
- Photographic products
- Computer software
Light, strong covers with visual impact
The use of CD and other media to convey knowledge and entertainment is increasing rapidly for a growing variety of purposes at work, at school and at home. Since there is no other distinct way, except by the cover, to display in advance what kind of information is stored on those media, this application of both informative and protective paperboard packaging is expanding.
This is a demanding application. CDs are fragile and sensitive to handling and the environment - they need good protection. Strength and light weight - not adding significantly to the weight of their contents - are important features of media covers. So are all characteristics which enhance a distinct and durable graphical presentation; there is often just a small area available to present an image of the often complex contents of the media.
Choice of paperboard
Discs for information storage are promoted by brand identity. In contrast, shelf appeal is the main promotional feature of media as carriers of, for example, artistic and intellectual works. The shelf appeal is primarily achieved by the visual impact of the surface decoration. Although the size of the cover is usually small, fold out panels may be used to increase the freedom of design. A huge variety of decorative means are available to create a distinct and expressive visual impact; printed illustrations and photographs, embossing, hot foil stamping or foil lamination can be used.
Important promotional characteristics of paperboard for media covers are whiteness, smoothness and surface finish, often required on both sides. Very high print quality, with good contrast between the surface and the print, is required to achieve excellent presentation of sharp half-tone illustrations or bold, strong colours in large solid areas. Accurate registration of printed text is also necessary. Embossing, lamination and hot foil stamping require surface strength. The choice of a special surface finish is part of the visual impact - high gloss or a smooth, silky surface. The structural shape of the cover calls for a strong and tough multiply paperboard.
Media covers are required to be strong and tough, yet light in weight, not adding too much weight to their fragile contents. The protective characteristics need not only last through distribution, storage and handling at the point of sale - but also for years in use. The shape, function and graphical presentation of the covers are required to endure for many years without deteriorating. An additional important requirement is that no chemical interaction or dust should affect the surface of the packed product. The use of virgin fibres and selected coatings secure this aspect of protection.
Important protective characteristics of paperboard for media covers are strength and toughness, together with folding rigidity and tearing resistance. Good stiffness, creasing and gluing properties ensure a strong cover. A smooth surface provides for ease of handling, good rub and abrasion resistance. The use of virgin fibres provides for creases which are durable to repeated opening and closing. Together with selected coating ingredients, the use of virgin fibres also ensures good light stability, preventing the graphical presentation from yellowing due to ageing.
Printing and conversion
To obtain efficiency in printing and conversion a flat, stable and dust free paperboard is required. Good absorption and drying properties, as well as good cutting, creasing and gluing properties are important. Thus a high print quality is ensured, whilst process stoppages and material waste are minimised. For prestigious covers, produced in a multi-step process, paperboard with extremely good dimensional stability and sheet squareness is needed, to achieve perfect registration.
Media covers usually have a narrow, rectangular cross section. They are packed mechanically at high speed. CD covers require deep, narrow creases which fold easily.