Making the Most of Paperboard
By Tom Kerchiss, RK Print Coat Instruments
Paperboard is for many brand owners and product marketing departments, the dream material. It has great environmental credentials. Unlike many packaging materials it is derived from inherently renewable and recyclable sources. Paperboards impact on the environment is largely positive. Trees, as the saying goes – ‘Are the lungs of the earth’. A well-managed tree plantation has the potential to produce an endless supply of paperboard. Once used, recycled and reprocessed and converted it is possible as either a coated or uncoated material to go on to produce products as diverse as shoe boxes, dry food packaging, soap and laundry detergent packaging, cereal boxes and even composite fibre containers.
Paperboard’s receptive surface provides printers and converters with the opportunity to shine and to interpret design layout according to product requirements and the expectation of the brand owner.
Paperboard is available in a variety of grades; it is a versatile packaging medium, and although generally formatted into a conventional rectangular box shape, it can be shaped into a number of geometric configurations including pyramids and circles.
Cartons can be made for hanging on a retail hook rather than stacked end to end or side to side on a retailing shelf; cartons can be made with curved panels and rounded corners; cartons can be lined or plastic coated in order that the pack or carton or, as is often the case, the beverage container is leak proof and is equipped with specific barrier protective properties, making them suitable for juice or milk products.
With regards to plastic coated paperboard products they may be structured in various ways. The material may be PE-coated on both sides and incorporate heat sealed side and end seals. Paperboard that is subject to PE-coating can also be foil/plastic laminate lined, etc.
Rigid card is used in blister and skin packaging; material can also be shaped as tubs for ice cream tubs and is often supplied with an accompanying circular lid of card.
Value added processes dramatically enhance packaging appearance. Surfaces can be embossed, de-bossed and depending upon the grade and type of material chosen surfaces can be hot stamped and laminated with metallised polyethylene film laminates or printed with metallic inks. Conversion processes enable areas of a product surface to accept holographic images and effect varnishes.
Sometimes its not necessary to incorporate all the decorate bells and whistles, packaging should be appropriate for the environment in which the product is to be displayed and should be in keeping with the product being sold.
To take an example, surface coatings such as varnish may, apart from printing be all that might be necessary for many applications. The varnish provides an attractive gloss and at the same time it also protects the print against scuffs and minor transport knocks.
Paperboard generally provides marketers and designers with one of the largest surface areas for the placement of colour, graphics and informational content. However, it can be all too easy to get carried away during the design stage. One must never lose sight of the fact that there is a great deal of difference between a design that looks good and one that prints well.
A good design is one that can be printed at high speed and for which acceptable colour saturation can be obtained and then maintained throughout the entire tonal range. If processes such as flexography are involved an optimised flexo design would be one that allows for proper traps, colour balance and screening of final proof.
Designs that do not take into account the print process and the characteristics of the substrate do not necessarily spell disaster in terms of ‘final’ product output – but they do slow print output, contribute to machine downtime; increase the need to make adjustments to ink and tend to generate an excessive amount of material and consumable waste. Colour communication or proofing devices such as the FlexiProof and K Printing Proofer can help to minimise these sorts of problems and assist in resolving colour matching and other issues.
According to industry statistics and in terms of market segmentation, the majority of paperboard related output is centred on corrugated, folding carton and containers for liquid packaging with around 10 to 12 per cent destined for hanger, tubs, tubes and specialist items. Because job run requirements still tend to be on the low side (often in the region of 5,000 units), printers and converters need to be masters of the quick changeover.
Productivity enhancers such as the FlexiProof, FlexiProof UV or FlexiProof LED UV can be used for colour matching, determining ink/coating/substrate interaction and for evaluating printability and performance properties including gloss, scuff resistance, chemical resistance, flexibility and durability. Products can be trialled on the FlexiProof often circumnavigating the need to mount a job on a production machine; minimising the need to adjust inks on press, minimising waste and as a consequence speeding production machine make ready and helping to improve profitability.
Colour communication issues, getting colour right time after time is obviously one area of particular concern to printers, converters and their customers, but it’s not the only area of processing that needs long term attention. Products, such as coatings, inks need to be developed and monitored under real world conditions, prior to becoming commercially available.
In the product development environment and in a converting scenario there is a need to determine for example: the best and most economical method of coating. This has lead to the development of new quality control and product development equipment and systems that are adaptable enough so that potentially problematic commercial and productivity issues can be resolved.
Tackling problems on the fly and in the pressroom or coating shop environment is something that most companies would like to keep to the minimum. Manufacturers certainly don’t want to market products that may at some point be returned to them because of complaints. The same applies to products produced in the converting shop on equipment such as a coater or laminator and destined to appear in the retail environment.
The new VCML Lab/Pilot Coater introduced by RK Print Coat Instruments enables operators to trial unfamiliar materials, test various materials and formula and to determine the most suitable and most economically effective print, coat, laminate or drying/curing technology to use for an intended application. This reel-to-reel system is touch screen controlled and is particularly useful for product development, quality control and for low volume production of specialised products.
The VCML Lab/Pilot Coater has a web width of up to 300 mm and can print. Coat and laminate on all type of flexible substrates. A well-rounded and comprehensive system - flexography, offset gravure, gravure, slot die, reverse coating, meter bar, knife-over-roll and many other processing technologies are selectable.
The VCML Lab/Pilot Coater can be configured for hot air drying, infrared and UV curing with performance enhancing accessories such as corona treater, electronic closed loop tension control and ATEX coating zone also available.
Equipped with a cantilevered unwind and rewind, head mounting station with tray lift and trough and a laminator with pneumatic nip the VCML Lab/Pilot Coater enables users to apply various inks, varnishes, adhesives and paint using both water-based and solvent formulations.
The VCML Lab/Pilot Coater and it’s high tech bespoke counterpart, the
VCM Coater provides product developers, converters and manufacturers with coating and other process solutions to meet a wide range of needs. This includes meeting the challenge of producing alternative materials to many of the products used today and which are now considered unacceptable.
RK Print Coat Instruments Ltd
Litlington, Royston, Hertfordshire SG8 0QZ
www.rkprint.com sales@rkprint.com
Source: RK Print Coat Instruments Ltd
