Packaging Technology and Engineering. Dipak Kumar Sarker

Figure 1.2 Survey of packaging use: the needs fulfilled by packaging.

Figure 1.2 shows that the role of packaging is associated with a cluster of needs. The packaging needs include technological requirements that fit societal or speciality requirements, such as multiple opening and resealing. Legal requirements and political compliance include wastage and recycling guidelines; social and cultural requirements are also important, often mapping to creeds and cultures such as halal or kosher foods (and the guarantee of freedom from animal‐derived materials, e.g. gelatin or dairy produce). Further needs for most packaging also involve cost minimisation, which is linked to financial accessibility and economic drivers [3], and ubiquitously sourced materials with no restrictions on availability. Demographic requirements, which might include easy access or restriction‐to‐access packaging for the elderly and infants, often define the needs for some high‐risk products. Finally, and of increasingly important decision‐informing status, concerns about environmental impact, issues covering material sustainability, and efforts to recycle and reuse without impact on the anthrosphere, geosphere, or biosphere have a powerful role in product engineering and composition. All these needs amalgamate to dictate the overall requirements placed on packaging materials and their routine use in the commercial sector.

Central to the use of various types of packaging are the pivotal notions of their role (primary, secondary, and tertiary) and what type of environment might be appropriate for the packaging (Figure 1.2). For example, plastic may be the best first choice but then, given the informing nature of the container, use of printed paperboard may present the best financial choice. The selection of packaging use is modelled against maintenance of standards, conveyance of identity, mechanical strength, product quality (both required and obtainable), and the purity required of the contained goods (particularly true of medicines). A good pack, therefore, needs to provide full information, be familiar or instantly recognisable, be based on a design for frequent or intermittent use (as required), and demonstrate suitability for its intended use. Additionally, where portioning of the product is required, such as multi‐vitamins, infant formula, dietary or meal replacements, or traditional pharmaceuticals, careful control of doses leads to medical and therapeutic compliance. Marketing and identity, aligned with matching product trends in pack volume, size, and form, are often indicators of product success. Because of the nature of the commercial sector packages need to be able to conform to high‐output manufacturing but also need some thought embedded in the design as a ‘superior’ quality product can have an associated cost. Reliable packaging universally prevents water and humidity breach and demonstrates mechanical resistance (shock, strength), chemical resistance (absorption; corrosion; air and gas exclusion; chemical, sterilant, or pH resistivity), microbial resistance, ease of handling, ease of repeated processing, and light exclusion. Regulation adherence of the materials used and framed pragmatically within the commercial goals of high‐numbered product sales must consider materials, product manufacture, and logistical cost – this usually means the pack should be lightweight, easily packed, and yet physically robust. The unit cost of the product given its manufacturing and shipping costs gives rise to the idea of lean manufacturing and cost trimming, some of which might arise from contact with a regular supplier and specific business approaches, such as just‐in‐time manufacturing.

      In order to satisfy the requirements of intimate contact with the contents, all packaging should ideally be chemically inert, unreactive, non‐additive, non‐absorptive, and, therefore, does not add to or corrupt the pack contents. Additionally, the package is required by the manufacturer and customer alike to offer protection against deterioration and contamination during handling and transport. Storage and transport conditions are likely to vary considerably and will include alterations in freezer conditions, cold‐room conditions, and ambient or room temperature handling. Strict control of the physical and spatial separation of packs is needed during storage as this may encourage temperature and pressure gradients in the pack, possibly leading to weaknesses, pinholes, tears, and cracks. A regular part of the development of commercial products will, therefore, consist of inspections, history‐marking steps, label scrutiny, sampling procedures, establishment of non‐conformance or rejection criteria, record‐keeping for shipments, and product security during transportation and the distribution chain. As a ‘protector’ of the product within, the packaging has a key role in resisting physical impacts, such as is seen with perishables in the squashing, wetting, and bruising of shipped fruit. Packaging, therefore, allows for the product to reach the consumer in the most economical and ideal way possible despite the transit time and variable conditions experienced during shipment and storage. As a result of modern societal changes, including changes in family dynamics and time spent in traditional activities, such as cooking, there have been a number of changes required for commercial products, such as foods. Highly packaged goods are often preferred in modern times because people have less time to pursue ‘traditional’ preparatory activities in the household and there is a higher need for convenience but with the guarantee of safety and hygiene. Consequently, packaging consumption is higher in developed than in developing countries, the latter of which in turn consume more packaging than underdeveloped countries. This must be balanced against sociopolitical notions, such as global warming (from incineration and refining), recycling, and environmental pollution, which are more evident and higher on the political agenda in the developed world.

      1.2.1 Primary, Secondary, and Tertiary Packaging

Packaging type is classified into three rather subjective categories based entirely on their areas of use. Primary packaging (cf. sales packaging) is defined as the packaging that surrounds the product when sold to and received by the final consumer. In essence, it includes the packaging material substance or product that is in direct contact with the fill product and the other packaging components (i.e. lid, instructions). Secondary packaging, also referred to as group or grouping packaging, is packaging used to collate or hold together the primary packaging or units being sold and is used for ease