Day-Date 40

228235 - 83415

Brand  : Rolex
Collection  : Oyster Perpetual
Model  : Day-Date 40
Reference  : 228235 - 83415
Complement : Everose gold
On sale : 2015

34 400 €Recorded list price in FranceI WANT IT

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  • Brand  : Rolex
    Collection  : Oyster Perpetual
    Model  : Day-Date 40
    Reference  : 228235 - 83415
    Complement : Everose gold
    On sale : 2015
    List Price : 34 400 €
    Diameter : 40 mm
    Styles : Classical
    Types : Self-winding
    Calibre : Calibre 3255 Manufacture Rolex
    Calibre distinction : Chronometer
    COSC certified
    And Rolex chronometer tests
    Complication : Days Indicator
    Date
    Case material : Everose gold
    Case peculiarity : Screwed-down caseback
    Screwed-down crown
    Shape : Round
    Water-resistance : 100 meters
    Dial : Sun Satin-finished
    Adorned
    Dial color : Pink
    Gold-plated
    Display : Luminescent hands
    Pink gold hands
    Indexes : Baton-type
    Luminescent
    Pink gold index
    Glass : Antireflective coating
    Sapphire
    With lens
    Strap material : Everose gold
    Strap clasp : Crownclasp
    + More characteristics : MOVEMENT
    Perpetual. mechanical. self-winding
    Calibre 3255. Manufacture Rolex
    Bidirectional self-winding via Perpetual rotor
    Official COSC certificate + Rolex chronometer tests
    Oscillator: Paramagnetic blue Parachrom hairsprin gwith Breguet overcoil
    Escapement: Chronergy with optimized energy efficiency
    Frequency:28.800 beats/hour (4 Hz)
    31 rubies
    Approximately 70-hour power

    Functions
    Centre hour. minute and seconds hands Instantaneous day and date in apertures. unrestricted rapid-setting. Stop-seconds for precise time setting

    CASE
    Oyster. Monobloc middle case. screw-down case back and winding crown
    18 ct Everose gold
    Fluted bezel
    Screw-down winding crown. Twinlock double waterproofness system
    Scratch-resistant sapphire crystal. Cyclops lens over the date
     
    DIAL
    Sundust. stripe motif
    18 ct pink gold indexes and hands. with Chromailght

    BRACELET
    President. semi-circular three-piece links
    18 ct Everose gold

    Concealed folding Crownclasp

DESCRIPTION

  • BASELWORLD 2015

    ROLEX

    DAY-DATE 40
    THE ULTIMATE STATUS WATCH


    THE OYSTER PERPETUAL DAY-DATE, ROLEX’S MOST PRESTIGIOUS MODEL, IS A WATCH LIKE NO OTHER. A TRUE WATCHMAKING ICON WITH A FORMIDABLE DESTINY, THIS IS A SUPERLATIVE CHRONOMETER IN EVERY WAY AND HAS BEEN WORN BY MORE HEADS OF STATE, LEADERS AND VISIONARIES THAN ANY OTHER WATCH. CREATED IN 1956, AVAILABLE EXCLUSIVELY IN GOLD OR PLATINUM, THE DAY-DATE IS UNIVERSALLY KNOWN AS THE “PRESIDENTS’ WATCH”, THE ULTIMATE STATUS WATCH CHOSEN BY THE WORLD’S GREAT NAMES FOR ITS PERFORMANCE AND EXCEPTIONAL PRESENCE.

    AT THE SUMMIT OF WATCHMAKING

    The Day-Date owes its reputation and prestige first and foremost to its exceptional horological qualities. It benefits from all the innovations that have given Rolex watches their place at the summit of the contemporary art of watchmaking. Its principal characteristics are, in fact, summed up on the dial: Oyster Perpetual, Day-Date, and Superlative Chronometer Officially Certified. Each of these markings highlights one of the features that make this a truly exceptional timepiece.

    The Day-Date is an Oyster, a worthy heir of the first wristwatch in the world with a waterproof case, which was created by Rolex 30 years earlier in 1926. Thanks to an ingenious patented system consisting of a hermetically screwed-down case back and winding crown, the Oyster brought the definitive response to one of the great challenges for the wristwatch: how to efficiently protect the mechanical movement from the hazards of dust, humidity and other outside elements.

    The Day-Date is also an Oyster Perpetual, which means that it is equipped with the “Perpetual” self-winding system with a free rotor patented by Rolex as of 1931 – a system later adopted by the whole watchmaking industry. The winding mechanism makes use of a half-moon-shaped oscillating weight that turns freely through 360° to transform every movement of the wrist into a source of energy to automatically wind the watch. An ideal complement to the Oyster case, it eliminated the need to unscrew the crown every day to manually wind the watch, thereby avoiding any risk of compromising the water proof ness of the case. The Perpetual system furthermore provides a constant supply of energy to the movement, for signifi cantly greater regularity and precision. With the Oyster Perpetual, Rolex laid the foundations  of the modern waterproof and self-winding wristwatch. The Day-Date, when it was launched, brought the modern wristwatch to its apogee.

    A LEADERS’ CALENDAR

    The Day-Date also carries on its dial the calendar functions that inspired its name. This calendar display, prompted by the founder of Rolex himself, was unique at the time for a wristwatch. With the Day-Date, Hans Wilsdorf designed a high-prestige Oyster Perpetual that offered a particularly useful function for people in positions of responsibility: a clear and legible indication of the day and date at a glance. Essential information required for scheduling, arranging meetings, or signing and dating contracts, which made the Day-Date the perfect watch for decision-makers. Its calendar was quite different from the standard calendars of the day. Like the first “tool watches” created by Rolex from 1953 on the basis of the Oyster Perpetual – such as the Explorer, or the Submariner – the Day-Date stood out for the eminently practical and legible presentation of its functions. Until then, wristwatches displayed the date by means of a hand which pointed to a date marking at the edge of the dial. More sophisticated calendars, known as “complete calendars”, added the month and day shortened to three letters in small windows at 10 and 2 o’clock on the dial, together with a large moon phase at 6 o’clock.

    In 1945, Rolex revolutionized calendar legibility with its Datejust, the first wristwatch chronometer to indicate the date in a window at 3 o’clock. The famous Cyclops lens, invented by Rolex, would be added in 1953 to further facilitate reading of the date. In 1956, with the Day-Date, Hans Wilsdorf perfected his modern calendar by adding the day of the week spelt out in full in a window at 12 o’clock on the dial.

    A carefully considered decision. In a letter a few years earlier, Hans Wilsdorf spoke about the classic calendar and explained that in his view the date and the day were the two most useful displays, because they change daily. So Rolex focused on the layout of this essential information, freeing up space on the dial to give them prominence.

    THE DAY-DATE HAS ALWAYS REPRESENTED THE SUMMIT OF THE ROLEX ART OF WATCHMAKING.


    This allowed the day to be shown in full for the first time on a wristwatch alongside the date – a conside rable advantage in terms of legibility, since it is well-known that the brain deciphers whole words better than abbreviations.

    A MIRACLE AT MIDNIGHT IN 26 LANGUAGES

    Numbers are a relatively universal language for indicating dates, but people of different cultures want to read the day of the week in their own script.

    The Day-Date’s calendar is available in a choice of 26 languages, from European languages to Chinese and Arabic, and including, for example, Hebrew, Russian, Greek, Japanese, Indonesian, Scandi navian languages, and even Latin – still used today in the Vatican. In 1956, the Day-Date became the first wristwatch to speak to heads of state, dignitaries and leaders from all over the world in their own languages.

    By displaying the day and date in windows, calendar reading is made easier: the eye does not need to search for the information around the edge of the dial. And thanks to a Rolex-patented mechanism, the discs bearing this information move forward one position at midnight, in the space of a few milli seconds, to show the new date and day. An instantaneous show that, when it was launched, was called a miracle at midnight.

    SUPERLATIVE CHRONOMETER

    The last marking on the Day-Date’s dial – the celebrated Superlative Chronometer Officially Certified – is probably the most emblematic and is present today on every Rolex Oyster. It is particularly symbolic in the case of the Day-Date because it underlines the exceptional precision of its movement.

    If a chronometer, by definition, is an officially tested high-precision watch that does not deviate from the exact time by more than a few seconds per day,  a Superlative Chronometer must perform even better. The notion of Superlative Chronometer was introduced by Rolex in the late 1950s to mark the elite status of its chronometers, which were required by Hans Wilsdorf to obtain the citation “particularly good results” at the official tests. As the standard-bearer of Rolex excellence, the Day-Date launched in 1956 was one of the first models to satisfy the demands and carry the new denomination, Superlative Chronometer Officially Certified, on its dial.

    Official chronometer testing certificates with the citation disappeared in 1973 with the creation of the Swiss Official Chronometer Testing Institute (COSC), a consolidation of the various Official Watch Rating Centres and which established new, stricter criteria. But the wording formulated by Rolex remains a proud reminder of the pioneering role of the brand and its quest for excellence in the field of chronometric precision for wristwatches ever since 1910.

    Now in 2015, Rolex has redefined the status of Superlative Chronometer with calibre 3255, its new-generation mechanical movement that equips the new Day-Date. Rolex has established a level of chronometric precision that surpasses the level defined by COSC criteria. The new Day-Date’s precision on the wrist satisfies criteria twice as exacting as those for an officially certified chronometer, reconnecting with the brand’s heritage and restoring full weight to the notion of Superlative Chronometer.

    Symbolically, “superlative” remains an emblematic qualifier for the Day-Date, over and above the notion of precision. The Day-Date is the last flagship model created by the founder of Rolex and can be considered Hans Wilsdorf’s ultimate achievement in his pursuit of excellence. And also as the watch that, more than any other, embodies the achievements, prestige and success of the brand – and of those who wear it.

    CALIBRE 3255
    NEW STANDARDS OF PERFORMANCE


    AT BASELWORLD 2015, ROLEX IS INTRODUCING CALIBRE 3255, A NEW-GENERATION MECHANICAL MOVEMENT THAT SETS NEW STANDARDS OF PERFORMANCE FOR THE CORE CHARACTERISTICS OF A WATCH MOVEMENT: PRECISION, POWER RESERVE, RELIABILITY, RESISTANCE TO SHOCKS AND MAGNETISM, AS WELL AS THE EASE AND CONVENIENCE OF ITS ADJUSTMENT.

    Calibre  3255’s criteria for precision in everyday wear are twice as exacting as those for an officially certified chronometer. 
    Its superlative accuracy is tested by Rolex  after the movement has been cased, using high-technology equipment and an exclusive methodology that simulates the conditions in which a watch is actually worn.
    Its power reserve extends to three days (approximately 70 hours), representing an increase of 24 hours (or 50 per cent) compared to that of the previous generation. This means that the watch will easily continue to run over a weekend without needing to be rewound.
    Calibre 3255 is impervious to magnetic interferences beyond the values encountered  in daily life.
    The movement’s resistance to shocks and  its reliability have been optimized at the level of its overall architecture as well as its individual components, and through the use of high- performance lubricants developed and synthesized in-house.
    Calibre 3255 offers enhanced convenience of efficient self-winding, distinct easy- to-sense positions on the winding stem, unrestricted calendar correction at any time and very precise time setting.

    FOURTEEN PATENTS

    A compelling example of avant-garde watch-making technology, this self-winding mechanical movement is entirely developed and manufactured by Rolex. It is backed by 14 patents and a number of innovative technological solutions relating not only to component design but also to processes involving new technologies that push back the limits of current production methods. More than 90 per cent of the movement parts have been redesigned and optimized, from those that produce and store energy (self-winding module and mainspring) to the regulating organ responsible for precision (oscillator), the gear train and the escapement. The escapement, which transmits the impulses required to maintain the oscillator’s steady beat, is enhanced by a major innovation

    CALIBRE 3255 KEY FIGURES

    PRECISION
    Twice as great as that of an official chronometer

    AUTONOMY
    Approximately 70 hours (+50 %)

    CHRONERGY ESCAPEMENT EFFICIENCY
    +15 %

    PATENTS
    14

    NEW COMPONENTS
    > 90 %

    NEW CHRONERGY ESCAPEMENT

    Rolex engineers devised and patented a new escapement that optimizes the efficiency of the Swiss lever escapement, the standard in Swiss watchmaking, but which has seen only limited technical evolution over the last 50 years. While favoured by watchmakers for its great reliability, the Swiss lever escapement has always suffered from low efficiency, relaying to the oscillator barely more than a third of the energy it receives from the mainspring via the gear train.
    The result of extensive research, the geometry of the new Rolex Chronergy escapement im-
    proves the efficiency of this key component by 15 per cent. Almost half of the increased power reserve of calibre 3255 can be ascribed to the escapement itself. Made of nickel- phosphorus, the Chronergy escapement is, furthermore, insensitive to magnetic interferences.

    EXCLUSIVE ROLEX SUPERLATIVE CHRONOMETER TESTS

    With this new-generation movement, Rolex sets a new level of chronometric precision with criteria surpassing those of COSC (the Swiss Official Chronometer Testing Institute). Rolex has developed a new methodology and high-technology equipment to test the precision of its Superlative Chronometers with tolerances that are twice as exacting as those for official certification, and under conditions that simulate the wearer’s real-life experience. These exclusive chronometer tests complement the official COSC certification, to which all Rolex movements continue to be submitted systematically, and are carried out not on the movements alone, but on the assembled watches after the movements have been cased.
    A specific test protocol was designed by Rolex following large-scale statistical studies to determine the actual conditions of daily wear. As a result, the Rolex chronometers equipped with movements tested according to this new methodology demonstrate superlative precision on the wrist.

    AN INDUSTRIAL CHALLENGE

    The exceptional performance of calibre 3255 is the result of years of research and development on horological components by Rolex engineers.
    It is also made possible by the Manufacture’s in-house expertise, covering all processes involved in movement production. This know-how has pushed back the boundaries  of production methods in terms of precision and tolerances, leading to enhanced component quality and perform ance. For example, through high- precision machining, the thickness of the walls of the barrel has been reduced by 50 per cent, resulting in a more than 10-hour gain in autonomy. The synthetic ruby pallet stones on the new Chronergy escapement’s pallet fork measure a mere 125 microns, 50 per cent less than those of the previous generation. A threefold enhancement in the poise of the oscillator balance wheel was  made possible thanks to precision manu facturing. High-technology processes are also used, such as LiGA (micromanu facturing by electro forming) to produce the paramagnetic pallet fork and escape wheel of the new Chronergy escapement.

    AESTHETIC HERITAGE

    Calibre 3255 benefits from new, updated aesthetics, both in the shape and arrangement of the bridges as well as in their meticulous, traditional decoration. The aesthetics have evolved while preserving the characteristic features of Rolex Perpetual movements, such as the red reversing wheels of the self-winding module, the golden yellow sinks, and the traversing balance bridge. Calibre 3255 consequently remains firmly in the aesthetic lineage of Oyster watch movements.

    KEY COMPONENTS OF CALIBRE 3255

    THE ENTIRE MECHANISM OF THE 3255 MOVEMENT HAS BEEN OPTIMIZED, FROM THE OSCILLATOR – THE GUARDIAN OF PRECISION – TO THE SELF-WINDING MODULE THAT SUPPLIES ITS ENERGY.

    PARAMAGNETIC OSCILLATOR WITH PARACHROM HAIRSPRING

    INNOVATIONS
    Optimized Breguet overcoil
    New high-precision-machined balance wheel for improved poise
    New patented balance staff for enhanced resistance to magnetism

    UNDERSTANDING THE OSCILLATOR

    The oscillator is the heart of a mechanical movement. Comprising a hairspring and a balance wheel, this regulating organ determines the precision of the watch by the regularity of its oscillations. The oscillator in a Rolex watch beats eight times per second, or more than 250 million times per year. For an oscillator to maintain its regularity, it must be able to resist external factors that can disrupt its performance, such as temperature variations, shocks, magnetic fields and the varying influence of gravity in different positions.

    THE OSCILLATOR OF CALIBRE 3255

    The oscillator of calibre 3255 is fitted with a blue Parachrom hairspring, patented and manufactured by Rolex in an exclusive alloy of niobium and zirconium. Insensitive to magnetic fields, the Parachrom hairspring offers great stability in the face of temperature variations and remains up to 10 times more precise than a traditional hairspring in case of shocks. It is equipped with an optimized Breguet overcoil, enhancing the isochronism of the oscillations in any position.
    The large balance wheel with variable inertia is fitted with four gold Microstella nuts enabling extremely precise regulating. Its redesigned geometry and the high-precision machining have enhanced the poise threefold.
    The oscillator is attached to a new balance staff with exclusive geometry offering increased resistance to magnetic interferences.
    It is fitted on high-performance Paraflex shock absorbers developed and patented by Rolex for increased resistance to shocks. The oscillator is held firmly in place by a traversing balance bridge, further reinforcing shock resistance. The balance bridge features an optimized height-adjustment system and new integrated protection for the balance wheel.

    CHRONERGY ESCAPEMENT WITH OPTIMIZED EFFICIENCY

    INNOVATIONS
    New geometry offering a 15% improvement in energy efficiency
    Paramagnetic components in nickel-phosphorus
    High-precision manufacturing via LiGA (micromanufacturing through electroforming)
    The new Chronergy escapement patented by Rolex optimizes the efficiency of the traditional Swiss lever escapement.
    The thickness of the pallet stones has been reduced by half while  the contact surfaces of the escape wheel teeth have been doubled.
    The escapement system is no longer in alignment but slightly offset, thus multiplying the lever effect.
    The escape wheel has  a cut-out design to make it lighter and reduce its inertia.

    UNDERSTANDING THE ESCAPEMENT

    The escapement plays a major role in how the movement functions. Its alternating beats produce the familiar “tick-tocks” of mechanical watches. Positioned between the gear train and the oscillator, it is the “key to time”. The escape wheel receives raw energy from the mainspring through the gears and transmits it to the oscillator, via impulses from the pallet fork. The oscillator’s regular back- and-forth motion determines the division of time, which the escapement in turn transmits to the hands via the gear train.
    This crucial system must function reliably  so as not to hinder the movement rate. Its alternating movement and the friction generated between parts occasion considerable energy loss. For this reason, the escapement is one of the parts with the greatest potential for improvement in a mechanical watch.

    THE ESCAPEMENT OF CALIBRE 3255

    The Chronergy escapement of calibre 3255, developed and patented by Rolex, is an optimized version of the Swiss lever escapement, the standard escapement used in mechanical watches. The Chronergy escapement enhances the Swiss lever escapement’s energy efficiency while preserving the reliability for which it is renowned.
    In order to develop greater efficiency, Rolex engineers analysed the functioning of the Swiss lever escapement using cutting-edge observation methods and numerical modelling to isolate the parameters that needed modification. Surprisingly, the solution they arrived at ran counter to prevailing horological thinking: the length ratios between the escape wheel teeth and the pallet stones were reversed.
    While the thickness of the pallet stones has been reduced by half, the contact surfaces of the escape wheel teeth have been doubled.
    Moreover, the escapement system is no longer in alignment but slightly offset, affording greater distance between the pallet fork and the balance wheel, thus multiplying the lever effect.
    The pallet fork and escape wheel are made of nickel-phosphorus to be insensitive to magnetic interferences. The pallet stones are synthetic rubies, as in a conventional escapement. The escape wheel has a cut-out design to make  it lighter and reduce its inertia.
    Together, these modifications to the geometry have increased the efficiency of the escapement by 15 per cent, contributing to almost half of the gain in calibre 3255’s power reserve.

    EFFICIENT GEAR TRAIN

    INNOVATIONS
    Optimized gear train
    High-performance lubricants synthesized by Rolex

    UNDERSTANDING THE GEAR TRAIN

    The gear train is the series of cogwheels that transmits energy from the barrel to the escapement. Through its different wheel sizes and gear ratios, it transforms the beats of the oscillator into the seconds, minutes and hours displayed by the hands. Correct lubrication of this mechanical assembly and high-quality lubricants are essential to ensure the proper functioning of the movement and its continued reliability over many years.

    THE GEAR TRAIN OF CALIBRE 3255

    The efficiency of the gear train has been optimized. Rolex has also developed, and synthesizes in-house, exclusive new high-performance lubricants with a considerably longer useful life and greater stability over time. Rolex is the only independent watch manufacturer to develop and synthesize its own lubricants.

    HIGH-CAPACITY BARREL

    INNOVATIONS
    A thin-walled barrel to accommodate a larger mainspring for increased autonomy

    UNDERSTANDING THE BARREL

    The barrel supplies energy to the movement. It contains the mainspring, whose powerful coils store the energy that is produced when the movement is wound, either manually  or through a self-winding system. As the mainspring uncoils, it releases a continuous flow of energy which is controlled by the alternating beats of the escapement. Energy from the mainspring is transmitted to the escapement and the oscillator through the gear train. The movement’s autonomy or power reserve between windings depends therefore on how much energy the mainspring can store and on the energy efficiency of the gear train and the escapement–oscillator assembly. Increasing the power reserve means either improving the escapement’s efficiency or enlarging the mainspring – or both, as Rolex has done with calibre 3255.

    THE BARREL OF CALIBRE 3255

    Space is at a premium inside a watch movement. To increase the capacity of the mainspring in calibre 3255 without increasing the size of the barrel housing it, Rolex decided to optimize the space inside the barrel by reducing the thickness of its walls by half. This solution represented a considerable challenge both for machining and for the production process, pushing back the boundaries of current production methods. The resulting gain in space allowed for the accommodation of a mainspring with greater capacity, thereby increasing the movement’s autonomy by more than 10 hours.

    ACCELERATED SELF-WINDING

    INNOVATIONS
    New cut-out monobloc oscillating weight on  a ball bearing
    New reversing wheels for faster, more efficient bidirectional winding

    UNDERSTANDING SELF-WINDING

    Energy stored by the mainspring must be regularly renewed, otherwise the movement would stop once it had used up its power reserve. Traditionally, mainsprings were hand wound, via the winding crown. In 1931, Rolex played a pioneering role when it developed a self-winding system for a wristwatch, which it patented as the Perpetual rotor. This mechanism, with its half-moon-shaped oscillating weight, continually winds the mainspring using nothing more than natural wrist movements. This way it supplies the movement with a steady and “perpetual” source of energy for as long as the watch is being worn.


    THE SELF-WINDING MODULE OF CALIBRE 3255

    Calibre 3255 is equipped with a self-winding module with a new-generation Perpetual rotor, for more rapid winding of the new high-capacity mainspring. The reversing wheel system enables winding in either direction of the weight rotation. This system has been optimized to reinforce its efficiency whatever the activity of the wearer. The now monobloc oscillating weight has been cut-out to absorb shocks. It is fitted on a ball bearing and is held at its centre by a single screw, thereby facilitating assembly.

    SIMPLIFIED SETTING MECHANISM

    INNOVATIONS
    Clearly defined, easily located setting positions
    Optimized adjustment speeds
    Correction of the calendar at any time
    Very precise time setting

    UNDERSTANDING THE SETTING MECHANISM

    The winding crown is the main interface between the watch movement and the wearer, who uses it to manually wind the movement or to set the time and functions. A sophisticated mechanism inside the movement activates the settings that correspond to the various positions of the winding stem.

    THE SETTING MECHANISM OF CALIBRE 3255

    The setting interface of calibre 3255 is more ergonomic and user-friendly. The stops marking the positions of the winding crown are distinct and easily sensed. The setting system has been optimized, making for faster day and date adjustment. Time setting is very precise with no play. The calendar can be corrected at any time with no restrictions, thanks to retractable fingers inside the mechanism.

  • BASELWORLD 2015

    ROLEX

    DAY-DATE 40
    THE ULTIMATE STATUS WATCH


    THE OYSTER PERPETUAL DAY-DATE, ROLEX’S MOST PRESTIGIOUS MODEL, IS A WATCH LIKE NO OTHER. A TRUE WATCHMAKING ICON WITH A FORMIDABLE DESTINY, THIS IS A SUPERLATIVE CHRONOMETER IN EVERY WAY AND HAS BEEN WORN BY MORE HEADS OF STATE, LEADERS AND VISIONARIES THAN ANY OTHER WATCH. CREATED IN 1956, AVAILABLE EXCLUSIVELY IN GOLD OR PLATINUM, THE DAY-DATE IS UNIVERSALLY KNOWN AS THE “PRESIDENTS’ WATCH”, THE ULTIMATE STATUS WATCH CHOSEN BY THE WORLD’S GREAT NAMES FOR ITS PERFORMANCE AND EXCEPTIONAL PRESENCE.

    AT THE SUMMIT OF WATCHMAKING

    The Day-Date owes its reputation and prestige first and foremost to its exceptional horological qualities. It benefits from all the innovations that have given Rolex watches their place at the summit of the contemporary art of watchmaking. Its principal characteristics are, in fact, summed up on the dial: Oyster Perpetual, Day-Date, and Superlative Chronometer Officially Certified. Each of these markings highlights one of the features that make this a truly exceptional timepiece.

    The Day-Date is an Oyster, a worthy heir of the first wristwatch in the world with a waterproof case, which was created by Rolex 30 years earlier in 1926. Thanks to an ingenious patented system consisting of a hermetically screwed-down case back and winding crown, the Oyster brought the definitive response to one of the great challenges for the wristwatch: how to efficiently protect the mechanical movement from the hazards of dust, humidity and other outside elements.

    The Day-Date is also an Oyster Perpetual, which means that it is equipped with the “Perpetual” self-winding system with a free rotor patented by Rolex as of 1931 – a system later adopted by the whole watchmaking industry. The winding mechanism makes use of a half-moon-shaped oscillating weight that turns freely through 360° to transform every movement of the wrist into a source of energy to automatically wind the watch. An ideal complement to the Oyster case, it eliminated the need to unscrew the crown every day to manually wind the watch, thereby avoiding any risk of compromising the water proof ness of the case. The Perpetual system furthermore provides a constant supply of energy to the movement, for signifi cantly greater regularity and precision. With the Oyster Perpetual, Rolex laid the foundations  of the modern waterproof and self-winding wristwatch. The Day-Date, when it was launched, brought the modern wristwatch to its apogee.

    A LEADERS’ CALENDAR

    The Day-Date also carries on its dial the calendar functions that inspired its name. This calendar display, prompted by the founder of Rolex himself, was unique at the time for a wristwatch. With the Day-Date, Hans Wilsdorf designed a high-prestige Oyster Perpetual that offered a particularly useful function for people in positions of responsibility: a clear and legible indication of the day and date at a glance. Essential information required for scheduling, arranging meetings, or signing and dating contracts, which made the Day-Date the perfect watch for decision-makers. Its calendar was quite different from the standard calendars of the day. Like the first “tool watches” created by Rolex from 1953 on the basis of the Oyster Perpetual – such as the Explorer, or the Submariner – the Day-Date stood out for the eminently practical and legible presentation of its functions. Until then, wristwatches displayed the date by means of a hand which pointed to a date marking at the edge of the dial. More sophisticated calendars, known as “complete calendars”, added the month and day shortened to three letters in small windows at 10 and 2 o’clock on the dial, together with a large moon phase at 6 o’clock.

    In 1945, Rolex revolutionized calendar legibility with its Datejust, the first wristwatch chronometer to indicate the date in a window at 3 o’clock. The famous Cyclops lens, invented by Rolex, would be added in 1953 to further facilitate reading of the date. In 1956, with the Day-Date, Hans Wilsdorf perfected his modern calendar by adding the day of the week spelt out in full in a window at 12 o’clock on the dial.

    A carefully considered decision. In a letter a few years earlier, Hans Wilsdorf spoke about the classic calendar and explained that in his view the date and the day were the two most useful displays, because they change daily. So Rolex focused on the layout of this essential information, freeing up space on the dial to give them prominence.

    THE DAY-DATE HAS ALWAYS REPRESENTED THE SUMMIT OF THE ROLEX ART OF WATCHMAKING.


    This allowed the day to be shown in full for the first time on a wristwatch alongside the date – a conside rable advantage in terms of legibility, since it is well-known that the brain deciphers whole words better than abbreviations.

    A MIRACLE AT MIDNIGHT IN 26 LANGUAGES

    Numbers are a relatively universal language for indicating dates, but people of different cultures want to read the day of the week in their own script.

    The Day-Date’s calendar is available in a choice of 26 languages, from European languages to Chinese and Arabic, and including, for example, Hebrew, Russian, Greek, Japanese, Indonesian, Scandi navian languages, and even Latin – still used today in the Vatican. In 1956, the Day-Date became the first wristwatch to speak to heads of state, dignitaries and leaders from all over the world in their own languages.

    By displaying the day and date in windows, calendar reading is made easier: the eye does not need to search for the information around the edge of the dial. And thanks to a Rolex-patented mechanism, the discs bearing this information move forward one position at midnight, in the space of a few milli seconds, to show the new date and day. An instantaneous show that, when it was launched, was called a miracle at midnight.

    SUPERLATIVE CHRONOMETER

    The last marking on the Day-Date’s dial – the celebrated Superlative Chronometer Officially Certified – is probably the most emblematic and is present today on every Rolex Oyster. It is particularly symbolic in the case of the Day-Date because it underlines the exceptional precision of its movement.

    If a chronometer, by definition, is an officially tested high-precision watch that does not deviate from the exact time by more than a few seconds per day,  a Superlative Chronometer must perform even better. The notion of Superlative Chronometer was introduced by Rolex in the late 1950s to mark the elite status of its chronometers, which were required by Hans Wilsdorf to obtain the citation “particularly good results” at the official tests. As the standard-bearer of Rolex excellence, the Day-Date launched in 1956 was one of the first models to satisfy the demands and carry the new denomination, Superlative Chronometer Officially Certified, on its dial.

    Official chronometer testing certificates with the citation disappeared in 1973 with the creation of the Swiss Official Chronometer Testing Institute (COSC), a consolidation of the various Official Watch Rating Centres and which established new, stricter criteria. But the wording formulated by Rolex remains a proud reminder of the pioneering role of the brand and its quest for excellence in the field of chronometric precision for wristwatches ever since 1910.

    Now in 2015, Rolex has redefined the status of Superlative Chronometer with calibre 3255, its new-generation mechanical movement that equips the new Day-Date. Rolex has established a level of chronometric precision that surpasses the level defined by COSC criteria. The new Day-Date’s precision on the wrist satisfies criteria twice as exacting as those for an officially certified chronometer, reconnecting with the brand’s heritage and restoring full weight to the notion of Superlative Chronometer.

    Symbolically, “superlative” remains an emblematic qualifier for the Day-Date, over and above the notion of precision. The Day-Date is the last flagship model created by the founder of Rolex and can be considered Hans Wilsdorf’s ultimate achievement in his pursuit of excellence. And also as the watch that, more than any other, embodies the achievements, prestige and success of the brand – and of those who wear it.

    CALIBRE 3255
    NEW STANDARDS OF PERFORMANCE


    AT BASELWORLD 2015, ROLEX IS INTRODUCING CALIBRE 3255, A NEW-GENERATION MECHANICAL MOVEMENT THAT SETS NEW STANDARDS OF PERFORMANCE FOR THE CORE CHARACTERISTICS OF A WATCH MOVEMENT: PRECISION, POWER RESERVE, RELIABILITY, RESISTANCE TO SHOCKS AND MAGNETISM, AS WELL AS THE EASE AND CONVENIENCE OF ITS ADJUSTMENT.

    Calibre  3255’s criteria for precision in everyday wear are twice as exacting as those for an officially certified chronometer. 
    Its superlative accuracy is tested by Rolex  after the movement has been cased, using high-technology equipment and an exclusive methodology that simulates the conditions in which a watch is actually worn.
    Its power reserve extends to three days (approximately 70 hours), representing an increase of 24 hours (or 50 per cent) compared to that of the previous generation. This means that the watch will easily continue to run over a weekend without needing to be rewound.
    Calibre 3255 is impervious to magnetic interferences beyond the values encountered  in daily life.
    The movement’s resistance to shocks and  its reliability have been optimized at the level of its overall architecture as well as its individual components, and through the use of high- performance lubricants developed and synthesized in-house.
    Calibre 3255 offers enhanced convenience of efficient self-winding, distinct easy- to-sense positions on the winding stem, unrestricted calendar correction at any time and very precise time setting.

    FOURTEEN PATENTS

    A compelling example of avant-garde watch-making technology, this self-winding mechanical movement is entirely developed and manufactured by Rolex. It is backed by 14 patents and a number of innovative technological solutions relating not only to component design but also to processes involving new technologies that push back the limits of current production methods. More than 90 per cent of the movement parts have been redesigned and optimized, from those that produce and store energy (self-winding module and mainspring) to the regulating organ responsible for precision (oscillator), the gear train and the escapement. The escapement, which transmits the impulses required to maintain the oscillator’s steady beat, is enhanced by a major innovation

    CALIBRE 3255 KEY FIGURES

    PRECISION
    Twice as great as that of an official chronometer

    AUTONOMY
    Approximately 70 hours (+50 %)

    CHRONERGY ESCAPEMENT EFFICIENCY
    +15 %

    PATENTS
    14

    NEW COMPONENTS
    > 90 %

    NEW CHRONERGY ESCAPEMENT

    Rolex engineers devised and patented a new escapement that optimizes the efficiency of the Swiss lever escapement, the standard in Swiss watchmaking, but which has seen only limited technical evolution over the last 50 years. While favoured by watchmakers for its great reliability, the Swiss lever escapement has always suffered from low efficiency, relaying to the oscillator barely more than a third of the energy it receives from the mainspring via the gear train.
    The result of extensive research, the geometry of the new Rolex Chronergy escapement im-
    proves the efficiency of this key component by 15 per cent. Almost half of the increased power reserve of calibre 3255 can be ascribed to the escapement itself. Made of nickel- phosphorus, the Chronergy escapement is, furthermore, insensitive to magnetic interferences.

    EXCLUSIVE ROLEX SUPERLATIVE CHRONOMETER TESTS

    With this new-generation movement, Rolex sets a new level of chronometric precision with criteria surpassing those of COSC (the Swiss Official Chronometer Testing Institute). Rolex has developed a new methodology and high-technology equipment to test the precision of its Superlative Chronometers with tolerances that are twice as exacting as those for official certification, and under conditions that simulate the wearer’s real-life experience. These exclusive chronometer tests complement the official COSC certification, to which all Rolex movements continue to be submitted systematically, and are carried out not on the movements alone, but on the assembled watches after the movements have been cased.
    A specific test protocol was designed by Rolex following large-scale statistical studies to determine the actual conditions of daily wear. As a result, the Rolex chronometers equipped with movements tested according to this new methodology demonstrate superlative precision on the wrist.

    AN INDUSTRIAL CHALLENGE

    The exceptional performance of calibre 3255 is the result of years of research and development on horological components by Rolex engineers.
    It is also made possible by the Manufacture’s in-house expertise, covering all processes involved in movement production. This know-how has pushed back the boundaries  of production methods in terms of precision and tolerances, leading to enhanced component quality and perform ance. For example, through high- precision machining, the thickness of the walls of the barrel has been reduced by 50 per cent, resulting in a more than 10-hour gain in autonomy. The synthetic ruby pallet stones on the new Chronergy escapement’s pallet fork measure a mere 125 microns, 50 per cent less than those of the previous generation. A threefold enhancement in the poise of the oscillator balance wheel was  made possible thanks to precision manu facturing. High-technology processes are also used, such as LiGA (micromanu facturing by electro forming) to produce the paramagnetic pallet fork and escape wheel of the new Chronergy escapement.

    AESTHETIC HERITAGE

    Calibre 3255 benefits from new, updated aesthetics, both in the shape and arrangement of the bridges as well as in their meticulous, traditional decoration. The aesthetics have evolved while preserving the characteristic features of Rolex Perpetual movements, such as the red reversing wheels of the self-winding module, the golden yellow sinks, and the traversing balance bridge. Calibre 3255 consequently remains firmly in the aesthetic lineage of Oyster watch movements.

    KEY COMPONENTS OF CALIBRE 3255

    THE ENTIRE MECHANISM OF THE 3255 MOVEMENT HAS BEEN OPTIMIZED, FROM THE OSCILLATOR – THE GUARDIAN OF PRECISION – TO THE SELF-WINDING MODULE THAT SUPPLIES ITS ENERGY.

    PARAMAGNETIC OSCILLATOR WITH PARACHROM HAIRSPRING

    INNOVATIONS
    Optimized Breguet overcoil
    New high-precision-machined balance wheel for improved poise
    New patented balance staff for enhanced resistance to magnetism

    UNDERSTANDING THE OSCILLATOR

    The oscillator is the heart of a mechanical movement. Comprising a hairspring and a balance wheel, this regulating organ determines the precision of the watch by the regularity of its oscillations. The oscillator in a Rolex watch beats eight times per second, or more than 250 million times per year. For an oscillator to maintain its regularity, it must be able to resist external factors that can disrupt its performance, such as temperature variations, shocks, magnetic fields and the varying influence of gravity in different positions.

    THE OSCILLATOR OF CALIBRE 3255

    The oscillator of calibre 3255 is fitted with a blue Parachrom hairspring, patented and manufactured by Rolex in an exclusive alloy of niobium and zirconium. Insensitive to magnetic fields, the Parachrom hairspring offers great stability in the face of temperature variations and remains up to 10 times more precise than a traditional hairspring in case of shocks. It is equipped with an optimized Breguet overcoil, enhancing the isochronism of the oscillations in any position.
    The large balance wheel with variable inertia is fitted with four gold Microstella nuts enabling extremely precise regulating. Its redesigned geometry and the high-precision machining have enhanced the poise threefold.
    The oscillator is attached to a new balance staff with exclusive geometry offering increased resistance to magnetic interferences.
    It is fitted on high-performance Paraflex shock absorbers developed and patented by Rolex for increased resistance to shocks. The oscillator is held firmly in place by a traversing balance bridge, further reinforcing shock resistance. The balance bridge features an optimized height-adjustment system and new integrated protection for the balance wheel.

    CHRONERGY ESCAPEMENT WITH OPTIMIZED EFFICIENCY

    INNOVATIONS
    New geometry offering a 15% improvement in energy efficiency
    Paramagnetic components in nickel-phosphorus
    High-precision manufacturing via LiGA (micromanufacturing through electroforming)
    The new Chronergy escapement patented by Rolex optimizes the efficiency of the traditional Swiss lever escapement.
    The thickness of the pallet stones has been reduced by half while  the contact surfaces of the escape wheel teeth have been doubled.
    The escapement system is no longer in alignment but slightly offset, thus multiplying the lever effect.
    The escape wheel has  a cut-out design to make it lighter and reduce its inertia.

    UNDERSTANDING THE ESCAPEMENT

    The escapement plays a major role in how the movement functions. Its alternating beats produce the familiar “tick-tocks” of mechanical watches. Positioned between the gear train and the oscillator, it is the “key to time”. The escape wheel receives raw energy from the mainspring through the gears and transmits it to the oscillator, via impulses from the pallet fork. The oscillator’s regular back- and-forth motion determines the division of time, which the escapement in turn transmits to the hands via the gear train.
    This crucial system must function reliably  so as not to hinder the movement rate. Its alternating movement and the friction generated between parts occasion considerable energy loss. For this reason, the escapement is one of the parts with the greatest potential for improvement in a mechanical watch.

    THE ESCAPEMENT OF CALIBRE 3255

    The Chronergy escapement of calibre 3255, developed and patented by Rolex, is an optimized version of the Swiss lever escapement, the standard escapement used in mechanical watches. The Chronergy escapement enhances the Swiss lever escapement’s energy efficiency while preserving the reliability for which it is renowned.
    In order to develop greater efficiency, Rolex engineers analysed the functioning of the Swiss lever escapement using cutting-edge observation methods and numerical modelling to isolate the parameters that needed modification. Surprisingly, the solution they arrived at ran counter to prevailing horological thinking: the length ratios between the escape wheel teeth and the pallet stones were reversed.
    While the thickness of the pallet stones has been reduced by half, the contact surfaces of the escape wheel teeth have been doubled.
    Moreover, the escapement system is no longer in alignment but slightly offset, affording greater distance between the pallet fork and the balance wheel, thus multiplying the lever effect.
    The pallet fork and escape wheel are made of nickel-phosphorus to be insensitive to magnetic interferences. The pallet stones are synthetic rubies, as in a conventional escapement. The escape wheel has a cut-out design to make  it lighter and reduce its inertia.
    Together, these modifications to the geometry have increased the efficiency of the escapement by 15 per cent, contributing to almost half of the gain in calibre 3255’s power reserve.

    EFFICIENT GEAR TRAIN

    INNOVATIONS
    Optimized gear train
    High-performance lubricants synthesized by Rolex

    UNDERSTANDING THE GEAR TRAIN

    The gear train is the series of cogwheels that transmits energy from the barrel to the escapement. Through its different wheel sizes and gear ratios, it transforms the beats of the oscillator into the seconds, minutes and hours displayed by the hands. Correct lubrication of this mechanical assembly and high-quality lubricants are essential to ensure the proper functioning of the movement and its continued reliability over many years.

    THE GEAR TRAIN OF CALIBRE 3255

    The efficiency of the gear train has been optimized. Rolex has also developed, and synthesizes in-house, exclusive new high-performance lubricants with a considerably longer useful life and greater stability over time. Rolex is the only independent watch manufacturer to develop and synthesize its own lubricants.

    HIGH-CAPACITY BARREL

    INNOVATIONS
    A thin-walled barrel to accommodate a larger mainspring for increased autonomy

    UNDERSTANDING THE BARREL

    The barrel supplies energy to the movement. It contains the mainspring, whose powerful coils store the energy that is produced when the movement is wound, either manually  or through a self-winding system. As the mainspring uncoils, it releases a continuous flow of energy which is controlled by the alternating beats of the escapement. Energy from the mainspring is transmitted to the escapement and the oscillator through the gear train. The movement’s autonomy or power reserve between windings depends therefore on how much energy the mainspring can store and on the energy efficiency of the gear train and the escapement–oscillator assembly. Increasing the power reserve means either improving the escapement’s efficiency or enlarging the mainspring – or both, as Rolex has done with calibre 3255.

    THE BARREL OF CALIBRE 3255

    Space is at a premium inside a watch movement. To increase the capacity of the mainspring in calibre 3255 without increasing the size of the barrel housing it, Rolex decided to optimize the space inside the barrel by reducing the thickness of its walls by half. This solution represented a considerable challenge both for machining and for the production process, pushing back the boundaries of current production methods. The resulting gain in space allowed for the accommodation of a mainspring with greater capacity, thereby increasing the movement’s autonomy by more than 10 hours.

    ACCELERATED SELF-WINDING

    INNOVATIONS
    New cut-out monobloc oscillating weight on  a ball bearing
    New reversing wheels for faster, more efficient bidirectional winding

    UNDERSTANDING SELF-WINDING

    Energy stored by the mainspring must be regularly renewed, otherwise the movement would stop once it had used up its power reserve. Traditionally, mainsprings were hand wound, via the winding crown. In 1931, Rolex played a pioneering role when it developed a self-winding system for a wristwatch, which it patented as the Perpetual rotor. This mechanism, with its half-moon-shaped oscillating weight, continually winds the mainspring using nothing more than natural wrist movements. This way it supplies the movement with a steady and “perpetual” source of energy for as long as the watch is being worn.


    THE SELF-WINDING MODULE OF CALIBRE 3255

    Calibre 3255 is equipped with a self-winding module with a new-generation Perpetual rotor, for more rapid winding of the new high-capacity mainspring. The reversing wheel system enables winding in either direction of the weight rotation. This system has been optimized to reinforce its efficiency whatever the activity of the wearer. The now monobloc oscillating weight has been cut-out to absorb shocks. It is fitted on a ball bearing and is held at its centre by a single screw, thereby facilitating assembly.

    SIMPLIFIED SETTING MECHANISM

    INNOVATIONS
    Clearly defined, easily located setting positions
    Optimized adjustment speeds
    Correction of the calendar at any time
    Very precise time setting

    UNDERSTANDING THE SETTING MECHANISM

    The winding crown is the main interface between the watch movement and the wearer, who uses it to manually wind the movement or to set the time and functions. A sophisticated mechanism inside the movement activates the settings that correspond to the various positions of the winding stem.

    THE SETTING MECHANISM OF CALIBRE 3255

    The setting interface of calibre 3255 is more ergonomic and user-friendly. The stops marking the positions of the winding crown are distinct and easily sensed. The setting system has been optimized, making for faster day and date adjustment. Time setting is very precise with no play. The calendar can be corrected at any time with no restrictions, thanks to retractable fingers inside the mechanism.

  • Brand  : Rolex
    Collection  : Oyster Perpetual
    Model  : Day-Date 40
    Reference  : 228235 - 83415
    Complement : Everose gold
    On sale : 2015
    List Price : 34 400 €
    Diameter : 40 mm
    Styles : Classical
    Types : Self-winding
    Calibre : Calibre 3255 Manufacture Rolex
    Calibre distinction : Chronometer
    COSC certified
    And Rolex chronometer tests
    Complication : Days Indicator
    Date
    Case material : Everose gold
    Case peculiarity : Screwed-down caseback
    Screwed-down crown
    Shape : Round
    Water-resistance : 100 meters
    Dial : Sun Satin-finished
    Adorned
    Dial color : Pink
    Gold-plated
    Display : Luminescent hands
    Pink gold hands
    Indexes : Baton-type
    Luminescent
    Pink gold index
    Glass : Antireflective coating
    Sapphire
    With lens
    Strap material : Everose gold
    Strap clasp : Crownclasp
    More characteristics : MOVEMENT
    Perpetual. mechanical. self-winding
    Calibre 3255. Manufacture Rolex
    Bidirectional self-winding via Perpetual rotor
    Official COSC certificate + Rolex chronometer tests
    Oscillator: Paramagnetic blue Parachrom hairsprin gwith Breguet overcoil
    Escapement: Chronergy with optimized energy efficiency
    Frequency:28.800 beats/hour (4 Hz)
    31 rubies
    Approximately 70-hour power

    Functions
    Centre hour. minute and seconds hands Instantaneous day and date in apertures. unrestricted rapid-setting. Stop-seconds for precise time setting

    CASE
    Oyster. Monobloc middle case. screw-down case back and winding crown
    18 ct Everose gold
    Fluted bezel
    Screw-down winding crown. Twinlock double waterproofness system
    Scratch-resistant sapphire crystal. Cyclops lens over the date
     
    DIAL
    Sundust. stripe motif
    18 ct pink gold indexes and hands. with Chromailght

    BRACELET
    President. semi-circular three-piece links
    18 ct Everose gold

    Concealed folding Crownclasp