Sustainable Converting
Rotoflex raises the bar in finishing
By Tom Kerchiss, chairman of RK Print Coat Instruments I
n an age with more than its fair share of anxiety, many converters and brand owners around the world are concerned about the sustainability and recyclability of packaging materials and the ease with which newer and alternative materials to fossil fuel derivatives can be printed or converted. In reality, adapting to new materials and new ways of processing is nothing new. It is not that many decades back that campaigns put in motion by organisations such as Greenpeace and environmentalists resulted in the printing and converting industries replacing ozone depleting chemicals with plant based cleaning materials free from VOCs and HAP emissions.
Paper-based or paperboard hybrids may tick many of the right boxes for fl exibility and ease of processing. Paper from forest-managed resources would seem eminently suitable for meeting sustainability and recycling objectives, but, of course, paper in whatever guise will not meet every requirement. Even so, innovative synthetic paper products are on the point of becoming available for some of the most demanding of applications. These substrates and constructs are being developed in Japan and perhaps elsewhere and are said to off er good moisture or water/chemical resistance for soap and laundry items such as liquid fabric softeners.
The likelihood is that the substrates that the converter will come across and be asked to process will be a mix of paper and others; the biodegradable polymers derived from marine or from plant based or microbial sources. Packaging has always been a mishmash of materials. Whatever is decided upon materials are going to have to meet process circularity requirements and where plastic fi lmic materials must be used, should contain a high percentage of recycled content.
The fact that some of the chemistries and base materials currently being processed will, at the end of a useful life, break down to produce a mixture of water, carbon dioxide and a compost residue for re-use, is obviously being touted as useful, though there is still that CO2 element to contend with. There are various initiatives underway and substrates and consumables being trialled. Many of the materials being developed are associated with coating. For instance, chitosan, a derivative of crustacean shells, is being used as a protective barrier coating for paperboard substrates. Carvacrol, a component of oregano and various essential oils, is also being investigated as a possible coating formula for specifi c segments of packaging where microbial growth needs to be excluded or prevented from gaining hold for as long as possible.
RK Print Coat Instruments has become involved in the supply of a custom confi gured VCML pilot coater for the coating of cannabis-impregnated medical patches. The variety of substrates that this knife-over-roll coater is engaged in trialling includes seaweed polysaccharides such as alginate, agar and carrageenan. These are diffi cult to apply and cure because of the low solids content and high water content. Interestingly, this medical patch needs to be cured using steam rather than hot air. Bio-based materials such as cellulose, PLA, TPS (starch-based, corn, potatoes) and co-polyesters are biodegradable/compostable when they reach the end of their life cycle. Bagasse, derived from sugar cane, is being tried out for food service applications. Compostable, bagasse looks like cardboard and meets waste recycling objectives, but there are drawbacks, one of which is it takes some time to decompose in temperate and northern climes. Too much heat can also reduce the strength of a packaged item. An issue with some plant based material and compostable materials centres around the risk of methane build up. Methane is an even worse pollutant than CO2. Hopefully now that this has been identifi ed, measures will have been put in place to avoid this problem.
38
Dec 2024 / Jan 2025
www.convertermag.com
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58
