The first feature in issue 116 (January 2025) of Chronos Japan focuses on brands that are concentrating on developing their own movements, in an era where design and materials are often the main topics of discussion in the watch market. Under the title "In-Depth Appraisal of New Movements," it highlights noteworthy new movements and the models that incorporate them. A column from that feature is being reprinted on webChronos.
Text by Masayuki Hirota (Chronos-Japan)
Text & Edited by Yukiya Suzuki (Chronos-Japan)
Edited by Yuto Hosoda (Chronos-Japan)
[Article published in the July 2025 issue of Kronos Japan]
How widespread will silicone parts become now that they're legalized?
Silicon components are becoming commonplace. While they have become widely used, particularly in escapements, their adoption in the crucial hairspring remains elusive. However, the patent for silicon hairsprings is nearing its expiration. Silicon hairsprings are resistant to temperature changes and magnetism. The lifting of this patent could significantly alter the future of mechanical watches.
Silicone parts that will dramatically change the way mechanical watches are made.
The dramatic improvement in mechanical watch performance was undoubtedly rooted in the ETA 2020 problem. Unable to use ETA movements anymore, some manufacturers shifted to developing their own in-house movements. As a result, the performance of in-house movements changed dramatically in just 20 years. Who would have imagined that a standard automatic watch could have a power reserve of approximately three days?
Another reason is the widespread adoption of new materials. For example, parts molded with UV-LIGA have resulted in more precise gears, leading to the creation of unprecedentedly complex watches. However, the most important factor was the proliferation of silicon parts.
Initially, this was adopted to avoid using steel or Dalnico escape wheels and pallets. However, its properties of being non-magnetic and freely deformable made it ideal not only for escapements but also for hairsprings. Yet, there is still considerable opposition. Although more stable than before, it still does not have the same reliability as metal parts. Nevertheless, it is an undeniable fact that silicon has dramatically changed mechanical watches.
The patent for the use of such silicon material is about to expire. Previously, this patent was exclusively held by Ulysse Nardin, Rolex, Patek Philippe, and the Swatch Group. The Richemont Group experimentally used silicon balance springs, but it is said that they voluntarily withdrew the patent, probably to avoid a dispute with the Swatch Group. When that patent is released, it will cause a major upheaval in the watch industry.
A source within the Richemont Group stated that they will actively adopt silicon balance springs once the patents are lifted. One reason the group is promoting the sharing of core movements is the ease of introducing silicon balance springs. As preparation, each company within the Richemont Group is first changing the escapements to non-magnetic materials.
The LVMH Group is no exception. It is said that Tag Heuer abandoned the development of carbon hairsprings because the imminent deregulation of silicon materials was anticipated. At least high-end manufacturers will likely incorporate silicon hairsprings.
Incidentally, a regulator cannot be attached to a silicon hairspring, which is prone to cracking. This means that any movement that incorporates silicon hairsprings in the future will likely use a free-sprung balance. If that happens, the stability of mechanical watches on the market will likely become incomparably higher than it is now.
