Stretchable conductive inks have been in the commercialization mode for multiple years now. Arguably, it all started as a technology push. The big trend at the time was wearable technology and e-textiles. And, naturally, ink and paste suppliers did not want to be left behind. In this article we look at why conductive inks could have a compelling proposition to this market, at some of the reasons which have hindered market progress, and at the current state of progress.
To learn more please consult Conductive Ink Markets 2019-2029: Forecasts, Technologies, Players. This report provides the most comprehensive and authoritative view of the conductive inks and paste market. It provides insights based on primary intelligence obtained through interviews, visits, conference exhibition interactions, personal communications, and so on. It also offers detailed ten-year market forecasts segmented by application and material type as well as coverage of some 130 companies.
Conductive ink technology can offer a compelling proposition to this market. It is intrinsically an adaptable technology. This is an important capability because the requirements are varied and, in most cases, unknown even by the users. In fact, many variables exist including the substrate of choice, the degree of stretchability, the washability, the conductivity level, the cost, and so on.
An important advantage of ink technology is that it can be customized to cater to a broad spectrum of needs. This is a technological advantage that outperformers alternative choices with rigid and fixed performance characteristics. To exploit this, the suppliers should develop the organization capability and mindset to offer customized solutions.
The ink solutions can also be applied after the textile product has been manufactured following normal processes. In other words, the integration of the paste-based electronics need not interfere with the production of the textile part itself. This is possible because inks could be laminated, and heat transferred much as graphics are today. There is also ongoing innovation on the use of sacrificial layers.
Market and technology challenges
An ink or paste however is not a final product. To commercialize these solutions, the value chain therefore had to be first established. This has been (almost inevitably) a slow process. The product ideas have often been vague with uncertain prospects. This increase the risk of ink suppliers to go all-in into the development process. The paste amount per item is also small and likely to remain so. Inevitably, this necessitates a business model in which the ink is used across millions of items developed and sold by many.
The market exploration and segmentation phase was, and is not, straightforward. The paste-based solution is not a replacement of an existing component. New products need to be designed, created, and commercialized. This demand creation process requires patience as well as the organizational capability to conduct detailed strategic market segmentations.
The process is further complicated by the fact that a single product will not win the day. It might act as a catalyst and a useful market reference, but more wins will be needed. In fact, a robust sustained and diverse pipeline of successful products will be needed. This is inevitable because paste content per item is low and products themselves can be short-lived.
Furthermore, the textile market itself is diverse. Indeed, many at first have focused on wearable consumer textiles, neglecting other opportunities that might lie in the rear view including protective clothing, automotive textiles, and many other areas. Despite these challenges, the ultimate prize remains attractive because the textile market is enormous and fast paced with rapid product development cycles and a highly responsive value chain.
The ink technology itself was and is not a finished or perfect product. At first, the inks' conductivity changed too much with elongation. This change was also non-linear showing significant hysteresis. The inks were not really washable or that washability was very limited. In addition, the solutions were not elegant. The inks were applied on a planarizing plastic like TPU and then encapsulated after curing. As such, there was no, and there is still largely no, direct on-textile printing. The price is also an issue limiting the user to cases where the value can be justified.
The state of progress thus far
Despite these challenges, progress has been steady. The supplier base is now global and broad. This helps with the market exploration phase as it accelerates the market seeding phase and the suppliers collectively are likely to conduct a more effective strategic market segmentation. The value chain is also better established, and the users are somewhat more familiar with the reality vs the hype of e-textiles and are now better able to assess different enabling solutions. Indeed, our forecasts suggest that the e-textile market itself will grow in the medium and long term, thus lifting the market for all supply components too.
Left: snapshot of the market split in e-textiles in 2018. It shows that the majority of the market lies outside consumer use cases, e.g., fashion and sports/fitness. Right: Trend in growth of e-textiles. For more details please contact us.
Furthermore, the progress is evident in the number of prototypes and products being launched. The image below shows a few examples. The applications are diverse but seem to coalesce around a few specific functionalities. The most prominent is using stretchable Ag pastes as high-conductivity stretchable dry sensor electrodes. The first use cases were for measuring ECG and other signals in fitness clothing or in animals and now further use cases, e.g., monitoring pregnancy, are emerging. Given the diversity of the textile market, it may be that the first major success stories emerge in sectors outside consumer e-textiles, e.g., automotive.
In general, the market is still growing only in trickles. The wait for the major success story that will catalyse growth still goes on. Given the state of the technology and the experience of the industry, however, it is reasonable to think that such a win will arrive in the near future and that 2021/2022 can reasonably be considered as inflection years.
To learn more about stretchable conductive pastes please consult Conductive Ink Markets 2019-2029: Forecasts, Technologies, Players (www.IDTechEx.com/inks). This report provides the most comprehensive and authoritative view of the conductive inks and paste market, giving detailed ten-year market forecasts segmented by application and material type. The market forecasts are given in tonnage and value at the ink level. It provides a detailed assessment of more than 25 application sectors. It analyses the market needs/requirements, discuss the business dynamics, market leadership and technology change trends, competing solutions, latest product/prototype launches, key players and market forecasts in tonnes and value.
Examples of stretchable conductive ink applications. Arguably occupancy sensors in vehicles must offer some stretchability as the sensor film adopts to the weight and shape of the occupant. This conformability is achieved by pattern design, e.g., cut-out flexible film, and somewhat stretchable inks. This sensor is not included in our analysis. Source: IDTechEx Research
Top image: Ralph Lauren