After the first five material developments described in part 01, in the second part of Developments in Packaging Material, I will highlight the following developments:
1. Ready-to-use peel polymers offer resilience and easy opening,
2. New non-aluminium foil packaging for food and drink products,
3. Scientists create biodegradable Styrofoam from milk,
4. Amazing printing technique achieves stunning graphics on natural kraft paper,
5. Synthetic labelling adhesives for glass bottle labelling.
Ready-to-use peel polymers offer resilience and easy opening,
Dow Chemical claims its Sealution polyolefin-based, single pellet formulations offer a raft of advantages compared to conventional resins and blends. The ready-to-use material is suitable for use in blown and cast film applications and with polyethylene (PE) or polypropylene (PP) substrates. They can also be utilised across a broad range of peel seal applications, as Dow claims versatility, seal reliability and easy opening for its new range of peel polymer formulations for food packaging.
The polymer offers ease of opening with no tear stringing, while peel polymer technology keeps bags reliably intact through the packaging and shipping process, and yet also allows the bags to peel open easily and reliably where it should, when consumers pull to open them.
The polymers come fully formulated and therefore require no further on-line blending by packaging converters.
New non-aluminium foil packaging for food and drink products,
A new transparent, non-aluminium foil barrier film line for stick pack and flow wrapped food and drink applications is launched by Rollprint Packaging Products.
According to the packaging supplier, any product that is currently in a flow wrapped package, either with aluminium foil in the structure or a film that has been metalized, can use Overture One. Overture One is suitable for a wide variety of granular, powdered, liquid and solid applications such as stick packaging for powdered drinks.
Rollprint said the Overture One lamination is based on the company’s ClearFoil barrier-coated polyester and is coupled with an “aggressive sealant”.
The company claims that oxygen barrier levels are available as low as 0.0008 cc/100in2/24 hrs and moisture barrier properties are available down to 0.0008 g/100in2/24 hrs.
Scientists create biodegradable Styrofoam from milk,
US scientists have used the protein in milk and clay to develop a new lightweight biodegradable styrofoam material which they claim could be a substitute for traditional foamed plastics.
The results of the study, published in Biomacromolecules, shows that a material produced using cows milk is both biodegradable and strong enough for commercial uses with almost a third of the material breaking down within 30 days.
80 percent of the protein in cow milk is a substance called casein, which is already used in making adhesives and paper coatings.
“Casein shows good film-forming and coating properties as well as excellent barrier properties to non-polar substances (oxygen, carbon dioxide, and aromas). This makes it an excellent candidate for numerous applications, such as paper coatings, adhesives, and food packaging”, said the researchers.
However, casein on its own has limited mechanical strength and is water sensitive, which can restrict its practical applications. To make the casein more resilient and boost its resistance to water, the scientists blended in a small amount of clay and a reactive molecule called glyceraldehyde, which links casein’s protein molecules together.
The scientists freeze-dried the resulting mixture, removing the water to produce a spongy aerogel, a lightweight material. To make the gossamer foam stronger, they cured it in an oven and then tested its sturdiness.
“These foam-like materials hold promise for a wide range of applications where the low density and environmental friendliness are of great importance; the ultra-low-density layered architectures result in favourable mechanical and thermal insulation properties,” the study concluded.
Biomacromolecules (2010) – “Development of Biodegradable Foamlike Materials Based on Casein and Sodium Montmorillonite Clay”
Authors: Tassawuth Pojanavaraphan, Rathanawan Magaraphan, Bor-Sen Chiou and David A. Schiraldi
Printing technique achieves stunning graphics on natural kraft paper,
The granola-style food line of Kaytee Products targets consumers seeking natural pet food. Therefore Kaytee Products, also wanted a natural look and feel for its packaging.
The solution was a paperboard carton from Great Northern Corp., made from 100% FSC-certified controlled wood sources. The carton is 100% recyclable, and pets also can use it for foraging, shredding, and tunnelling.
The kraft packaging, designed by design agency Directions Inc, features an exceptional graphic printing quality. achieved through a process built around the use of UV inks and UV dry trapping of inks and coatings in web-based StrataGraph processes. First, a thin coat of white is laid down on the kraft-paperboard carton for silhouetting the image. This base layer makes brilliant whites, skin tones, and other colours pop on the carton.
As each colour of ink is applied, the carton moves through a fast-dry process. The dried ink forms a polymer that sits on top of the paperboard rather than being absorbed into it, also acting as a base for the next layer of ink. After printing is finished, the top layer is a lamination on the paperboard.
Synthetic labelling adhesives for glass bottle labelling.
For many years the brewing industry has relied on tried and trusted water-based casein adhesives to label its glass beverage bottles. Given that casein is a raw material derived from cow’s milk, the beverage industry’s adhesives budgets are affected by sharp periodic swings. The logical alternative is to use adhesives based on synthetic polymers, which offer the additional advantage of longer storage stability and lower consumption. Up to now, however, the products available on the market showed certain limitations when compared directly with casein adhesives.
German manufacturer Henkel developed a new range of high performance synthetic adhesives for glass bottle labelling. Henkel claims to have achieved a technological breakthrough with its new casein-free product series, Optal XP.
In addition to wet tack strength, the synthetic Optal XP adhesives have a high resistance to ice-water and condensation and, therefore, exhibit good adhesion to chilled glass surfaces. They also offer economic and ecological processing advantages when it comes to labelling re-usable bottles as deficits previously experienced with casein-free labelling adhesives have been overcome through significantly improved cleaning and wash-off performance.