Invented in 1955 by Dupont, Tyvek is a high-density non-woven polyethylene which bears the property of selective barrier and is recyclable. Tyvek is light weight and strong, having features of water, chemical, termite, rodent-resistance. In the five decades since its introduction, Tyvek has been put to several versatile applications like durable documents, tags and labels, travelers and military maps, protective  envelopes for postal services,  car covers for UV protection, etc.
 

The applications have also made their way to protective clothing which include laboratory coats and aprons; and suits for mechanics and painters, for one-time use. Apart from this, Tyvek has also made its mark in the fashion industry by being used in the crafting of clothes and accessories.

 

Tyvek as a print substrate

Tyvek has a density that is half of the paper at the same thickness and size. It is tougher than paper in terms of tear resistance, puncture resistance, scratch and rip resistant and also bears a higher strength-to-weight ratio than paper.
 

Tyvek is one of the printing materials with the highest opacity. The opacity range is 90-98%. Besides high opacity, Tyvek also has good dimensional stability. The dimensions of the sheet change by less than 0.01% between a relative humidity of 0-100% at a constant temperature.
 

Patnaik says, “Due to the light weight, smooth surface, high dimensional stability and opacity, together with the toughness and durability, Tyvek is well suited as a printing substrate. It can be printed by offset lithography, letterpress, flexography, gravure, screen process, dot matrix, thermal transfer, ion deposition, digital press applications and inkjet processes, using standard commercial printing equipment. Spunbonded Olefin can be printed either sheet- or web-fed.”

 

Tyvek as a packaging material

Tyvek is a unique packaging material providing light-weight, breathable and protection from thermal excursion with high strength.
 

Speaking on the latest trend in the application of Tyvek, Shyam Patnaik, segment leader for Tyvek at Dupont India, emphasises its increasing usage for perishable temperature sensitive products (PTSP).  

“India is a country which experiences extreme climatic fluctuations, with the temperatures soaring as high as 45 degree celsius and with rainfall of more than 150mm in some regions. With such conditions, it is essential to use appropriate packaging, which is the sole barrier in avoiding spoilage. Tyvek with its heat reflecting properties, resistance to water and breathability serves as the ideal substrate for packaging in the PTSP segment,” says Patnaik.
 

Illustrating via a pie-chart (fig-1), Patnaik says, “We observe that 36.3% rejections of PTSPs, the highest of all, are caused as a result of spoilage due to extreme temperatures.”

Emphasising on the cause of rejections, Patnaik adds, “Most of the perishable products are spoiled when they are packed and kept in storage, waiting to be transported. When the products are exposed to heat for a long time, they begin to perspire, which results in the release of ethylene and carbon dioxide. This activates metabolism in such products, which in turn reduces the shelf life. ”
 

Tyvek absorbs little or no moisture and the liquid simply runs off its smooth surface as it is made from high-density polyethylene fibres. Being a non-woven fabric, it also enables scattering of light, posing less operational hazards during handling.
 

“When an electromagnetic radiation wave of multiple wavelengths, such as sunlight, falls on a packaged product, there can be three types of interactions. Either the wavelength would be absorbed and converted to heat, or the wavelength would be reflected or it would be transmitted through the object. When perishables are packed in Tyvek, which reflects 98% of the solar spectrum, it helps to keep away the heat and thus avoid perishability and enhances the shelf life,” says Patnaik.

With an example of a leading pharmaceutical company in India(fig-2), Patnaik observes the journey of a PTSP from its production to its delivery to the final destination, with once the PTSP being transported is wrapped in Tyvek as compared to when wrapped in traditional stretch wrap.  “The observation illustrates that thermal  fluctuation of PTSP wrapped in Tyvek was much lesser as compared to the one wrapped in stretch wrap film or no cover in the ambient condition. Thus Tyvek can be used as a better alternative in the transportations of PTSP’s, to prevent thermal excursion and thus ensuring longer life to PTSP products during transportation” concludes Patnaik.

Tyvek at DesignYatra

Sidhesh Kanade of PrintWeek India spoke to Sudarshan Kullur, sales manager for Tyvek, at the recently held Kyoorius DesignYatra in Goa. Kullur highlighted the versatile applications of the substrate and gives an insight on its adaptations   Sidhesh V Kanade (SVK): So what are you displaying at DesignYatra and who are you targeting? Sudarshan Kullur (SK): We are displaying a host of Tyvek applications, a non-woven, tear resistant, recyclable, and 100% eco-friendly substrate by Dupont. These applications include using Tyvek for producing carry bags, calendars, posters, photo albums, car covers, umbrellas, etc. DesignYatra is an event where CEOs, designers and students congregate to celebrate the best in design. Our motive here is to spread awareness of Tyvek’s versatile applications.    SVK: What are the salient features of Tyvek? SK: Tyvek has a density that is half of the paper at the same thickness and size. We want people know that Tyvek can be used for mainstream printing, die-cutting. Plus, it can be slit, scored, laminated, embossed, grommeted and sewn. It can do anything that you do with the substrates available in the market.   SVK: What is the feedback from designers? SK: The response has been good. People in the design field are always in search of new substrates to experiment with. We are also distributing free sample sheets of Tyvek so that users can get acquainted with the nature of the substrate and can use it in their work.   SVK:  Dupont has been promoting Tyvek in government institutions. What segment are you focussing on? SK: Durable document segment promotes use Tyvek’s in production of mark-sheets, certificates, envelopes, which contain confidential documents. We supply Tyvek to government as well as private institutions. We have undertaken government projects in the south for three universities as well as taken up projects for some universities in the north. We have also provided Tyvek to print health cards for school children in Assam. We are targeting institutions which focus on retaining the aesthetics and at the same time see the need to preserve them without laminating them. Apart from this, we have been doing Rakhi envelopes for India Post since the past six years.    SVK: What is your feedback on DesignYatra? SK: In the past, printing exhibitions has been the only channel for promoting Tyvek. This was our first year at DesignYatra and in spite of not being a print-centric exhibition, the response has surpassed our expectations.  As a manufacturer, it’s not just the promotions, but the hands-on experience that helps in sales volumes. Here at DesignYatra, we have been able to directly interact and understand the expectations of our end-users, the ones who will conceive product ideas out of Tyvek. The exhibition has enabled us to reach a new segment of substrate users.