Watchmaking — even if it sounds trite — is a combination of art and science. The most compelling watches are those that push forward the frontiers of scientific inquiry and do so with artistic expressions that stimulate and enlighten. But even rarer are the ones in which the two distinct natures are, by necessity, one and the same. In the modern landscape of watchmaking, only a small number of watches are built on this precept and a fine example are the watches of Ressence. 

Ressence, which stands for “renaissance de l’essentiel” or “rebirth of the essential,” was founded in 2010 by Belgian industrial designer Benoît Mintiens. By that time, contemporary independent watchmaking — the kind the Opus series helped foster — had reached its apogee. Complicated mechanical contraptions that pushed the technological and aesthetic limits of horology, oftentimes at the expense of function, were much welcomed developments in a trade that was starting to seem parochial. But for Mintiens, whose past work covered the span from medical devices to high-speed trains, what was crucial was revisiting the basic functions of a mechanical watch, especially since technology had, well, become a real aid in technical development.

Benoît Mintiens, the founder and creative genius behind Ressence

Mintiens’ idea was to improve the visual passage of time and display it in a more organic and efficient way. To tell time on an analog watch, hands are necessary as they act as revolving pointers. However, watch hands are layered, which makes reading the time from an angle slightly more inconvenient. For optimal legibility, the solution was then to create a two-dimensional dial with hands that sat laterally on the same plane. To that end, the hands still had to traverse the dial but yet could not overlap.

The result are watches that are exotic inside out, with a string of proprietary technologies that have cemented their place in watchmaking. Time is presented by a nested set of satellite disks that rotate while maintaining an upright position. The whole assembly revolves once per hour, displaying the minutes, while the subdials are geared to turn faster to display the seconds and slower for the hours. In essence, it was a progressive take on regulator dial displays. 

Even 12 years on, what remains outstanding is the strength of Mintiens’ organic design philosophy, which permeates all levels of the watches — from the case and dial right down to the axles of the movement. A testament to the design’s versatility and ability to evolve, Ressence has introduced six different models to date, not counting initial experimental models such as the Zero and One Series that were produced in limited editions. 

A Cohesive Whole

The essential principle of Ressence traverses all aspects of a watch, giving signature to a holistically intuitive design that reflects the unique genius of its creator. While the watches may vary in shape, they all have an immaculate pebble-like appearance. As you’ll come to find, nothing is incidental on a Ressence watch; rather, everything is visually and structurally purposeful. 

An organic form is believed to be more relatable and comfortable as it closely resembles nature, and when worn on the wrist, it becomes a natural visual extension of your physical presence. Hence, the soft flowing curves from the case to the domed crystal form a visual continuity that sets the stage for the orbital dial display. In addition, Ressence watches are designed without a crown to achieve a seamless and completely symmetrical case. In its place is a retractable lever on a rotatable caseback. Winding and setting are done by turning the lever, which has been scaled to the user’s fingers, making it convenient to hold the watch and rotate its back, regardless of their handedness. Setting the time also winds the movement. This intuitive design is based on the precept that the watch only needs to be set when it has stopped running. 

It is impossible to delve further into a Ressence watch without acknowledging the central role the movement itself plays on the design of the dial. At the heart of all Ressence watches is a unique patented module for displaying the time known as ROCS, which stands for Ressence Orbital Convex System. The orbital display relies on a planetary gear system with biaxial satellite disks that are inclined to varying degrees. While they may look flat on certain models, the dial is actually slightly domed to match the curvature of the crystal above. A flush-mounted revolving dial plate, which is driven by the minute axle of an ETA base caliber, rotates once per hour, displaying the minutes. An arrangement of satellite gears drives the co-planar subdials inside the main dial plate at varying speeds to indicate the hours, seconds and so on, depending on the model. 

While planetary gear systems are relatively common in watchmaking, often used to drive power reserve indicators, the module in a Ressence watch is notably complex and unusual. The vast majority of movements are constructed with a 2.5-dimensional architecture, meaning they are made up of gears arranged on different layers that are parallel to each other with axles that are perpendicular to the base plate and parallel to each other. Because the dial is slightly curved, the axles in the ROCS module also had to be inclined. Thus, the module is effectively three-dimensional, which on top of being complex to manufacture, poses a challenge for watchmakers who are accustomed to assembling 2.5-dimensional movements.

type 3

In 2013, Ressence introduced the Type 3, which was where the brand’s now-iconic design language took root. Beyond the unique characteristics inherent in a Ressence watch, the Type 3 was the first ever oil-filled mechanical timepiece. 

Ressence introduced its oil-filled technology with the Type 3, a world first in watchmaking

Handling the Type 3, as any number of first timers can attest, is a confounding experience, because the dial appears as if it is directly printed on the dramatically domed crystal, yet the small seconds hand is visibly ticking. This extraordinary effect is achieved by filling the entire module with transparent oil, eliminating refraction. Because the refractive index of the oil is near identical to that of the sapphire crystal, the gap becomes invisible, and the dial appears to be propped up against the crystal — three-dimensional yet planar and legible from any angle. This, in turn, also means that the wheels of the module are permanently lubricated, eliminating inertia and improving efficiency.  

When it comes to the ROCS 3 module developed for this model, two key words might set off alarm bells: “liquid” and “magnets” — one a solution to the other but both mortal enemies of watch movements. 

As mentioned, the orbital time display module in a standard Ressence is directly driven by the cannon pinion of the base movement. But because the ROCS is suspended in oil, it had to be completely isolated from the base movement.
Thus, with both layers no longer mechanically coupled, Ressence had to develop a magnetic transmission to link both chambers.

The chambers are separated by a hermetically sealed titanium membrane with several strong but tiny magnets positioned on either side, so energy can be transmitted from the base caliber to the module when two disks, on which the magnets are located, rotate together. To reduce the spread of magnetic fields, these magnets are further bookended by large magnetic conductors that concentrate the field in loops. On top of that, the entire base movement is shielded from residual magnetic fields by a Faraday cage, made from a proprietary alloy to protect the regulating organ.

Clockwise from top: Ressence’s patented module for displaying the time, known as the Ressence Orbital Convex system; The magnetic transmission used to connect the oil-filled module with the base movement in the Type 3 and 5; An ingenious system comprising of seven bellows is used to compensate for oil volume changes caused by temperature fluctuations

In addition to the hours, minutes, seconds and day, the watch incorporates a subdial for a mechanical thermal gauge. As oil is highly sensitive to temperature variations, the gauge is used to precisely indicate the optimal running temperature. A 0.5mm bimetal spiral is installed 0.1mm under the subdial. It changes in length with temperature, accounting for -5 to +55 degrees Celsius.

Notably, a semicircular structure located below the titanium membrane holds seven bellows that extend and compress to compensate for oil volume fluctuations as temperature rises and falls. This system also prevents the formation of air bubbles on the dial, which has to be filled tightly to achieve the unique optical illusion.

The effect is further enhanced by the massive size of the watch; the titanium case measures 44mm across, and because of the layered complexity of the movement as well as its double domed design, it is 15mm high. However, its form factor and tactile quality make it irresistibly wearable.

Type 1 

The Type 1 arrived a year later in 2014. It was a pure, pared-back alternative that has since evolved into the Type 1 Squared and Type 1 Slim. 

While the base movement and ROCS module are connected through a system of permanent magnets in the Type 3, they are mechanically coupled in the Type 1, allowing a more robust direct connection as well as a slimmer movement overall. As such, both watches have a modest case height of 11mm.

The Type 1 in two disparate nuanced forms; The Slim (left) with a tonneau case and the Squared (right) with cushion-shaped case

The Ressence Type 1 Squared marks a significant departure from previous Ressence designs in terms of its form. Ressence watches generally have a circular or ovoid form, which is an extension of the curvature of the crystal. The Type 1 Squared, however, as its name suggests, is almost a square. It has a cushion-shaped form with edges that extend just slightly from the dial, retaining its pebble-like appearance. Measuring 41mm across, it is made in stainless steel and has a polished finish that enhances the facets of the case and provides a beautiful contrast against the concentrically brushed dial.

On the other hand, the Type 1 Slim has a tonneau-shaped titanium case that is 42mm in diameter. Its lugless design and the nuanced geometry of its concave flanks, which expand outwards onto the wrist, make for an eminently sleeker, more modern profile.

Type 5 

To make the most out of the ingenious oil-filled display that offered vivid clarity, Mintiens soon developed a dive watch, launched in 2015 as the Type 5. Depth rated to 100m, the Type 5 is substantial in size at 46mm but manages to maintain a sleek and elegant profile due to its clean graphics, rear-mounted crown and distinctively domed dial. The case is in titanium, making it lightweight despite its diameter. It is paired with a black dial with engraved indications that are filled with Super-LumiNova for utmost legibility at depth.

The use of oil in the Type 5 dive watch ensures complete legibility when viewed from any angle underwater; It is equipped with a unidirectional bezel that has raised notches for easy grip as well as a locking system that prevents accidental winding of the case back

Like the Type 3, the ROCS 5 module is submerged in oil, creating the optical illusion of the dial merging with the crystal. This effect is particular fitting for a dive watch as it cancels out refractions that make most watches appear as mirrors underwater, unless viewed from the right angle. Additionally, because liquid cannot be compressed, the oil chamber maintains pressure equilibrium underwater.

Alongside the conventional hours, minutes and seconds, there is both a unidirectional bezel for dive timing and a temperature gauge. Further, a locking system, dubbed the Ressence Compression Lock System (RCLS), has been implemented to prevent accidental winding of the caseback while underwater. It locks as well as compresses the gasket to ensure water resistance.

Type 2 

Unveiled in 2018, with serial production beginning the following year, the Type 2 e-Crown was the first mechanical watch to feature a smart crown. It is an exemplar of how digital electronics and traditional mechanics can be artfully melded to form one paradigm-shifting package. Developed in collaboration with Tony Fadell, a Silicon Valley luminary best known as the “Father of the iPod,” the watch incorporates a solar-powered electronic module on an ETA caliber, enabling it to keep time autonomously.

The Type 2 e-Crown was the first mechanical watch to feature a smart crown, made possible by installing a solar-powered electronic module on top of mechanical movement

The e-Crown is activated and controlled via touch; double tapping the crystal awakens the electronic system, at which point it automatically resets to the correct time regardless of how much time has elapsed since it was left dormant. A single tap controls a function selector with four modes displayed on a colored subdial — time zone 1, time zone 2, e-Crown mode, and mechanical mode.

In e-Crown mode, the watch has to be paired, via Bluetooth, with an accompanying app, through which time is set automatically, adjusting itself for daylight savings, and where alternate time zones can also be controlled. On the other hand, in mechanical mode, the e-Crown function is disabled, and the watch runs purely mechanically.

Despite its 45mm diameter, the Type 2 makes for a comfortable experience on the wrist thanks to its slim, curved and crown less case

The automatic ETA movement powers the time display whereas the e-Crown module itself is charged by both the kinetic energy produced by the automatic rotor as well as solar energy via solar panels hidden beneath a dial with 10 micro-shutters that open to allow light in.

Though it relies on the brand’s signature nested set of rotating, satellite disks driven by planetary gears below the dial, the disks are mounted on jewel micro ball bearings for a slimmer architecture. The titanium case is a contemporary 45mm but a modest 12mm in height. 

Type 8

This year, Ressence has unveiled the Type 8 — a minimalist marvel and the most affordable Ressence model to date. It reprises many of the brand’s aesthetic and functional attributes but does away with a seconds subdial and features a simpler case construction. 

A distillation of Ressence’s unique language, the Type 8 forgoes the seconds sub-dial and features a streamlined and undeniably sleek case

Although it is 42.9mm large, the case is made of titanium, allowing the watch to clock in at a featherweight 42g overall with the strap included. The tapered case has a sandwich construction with satin-finished flanks that contrast nicely with a polished top surface. In classic Ressence style, its profile is characterized by a continuous flow from the case to the domed crystal, while the integrated lugs, which are cleverly obscured by a “skirt,” make for a seamless connection between case and strap. The winding and setting functions are done via the caseback, which is notched for better grip.

Like the Type 2, the signature orbital display is mounted on micro ball bearings, allowing for tighter tolerances between disks as well as a compact construction; the watch measures a slight 11mm in height.

Cheryl Chia

Cheryl Chia is a watch writer based in Singapore and is currently serving as Editor-at-Large of Revolution. Having spent the last seven years covering watches across various horological titles, she has cultivated a deep passion for independent watchmaking. Even though watches have elevated from lowly tools to luxury goods with an emotional dimension, she believes they can still be assessed objectively in terms of effort with respect to price.