Advanced Research Perpetual Calendar Ref. 5550P in Platinum

Reasons to Bid

The Patek Philippe Ref. 5550P ‘Advanced Research’ is the fourth installment of Patek Philippe’s experimental Advanced Research programme and one of the most important practical demonstrations of the maison’s silicon-based innovations. Unveiled at Baselworld 2011, the 5550P marries a classical perpetual-calendar wristwatch aesthetic with a radical, full-silicon regulating organ assembly, the OscilloMax ensemble, to create a watch that is at once conservative in appearance and revolutionary in technique. The 5550P is based on the 5140, but with a major technical twist. Although visually close to Patek’s standard 5140/5141 family of perpetual calendars, the 5550P is executed in platinum with a restrained, vertically brushed silver dial, applied gold hour markers and a discreet loupe on the on the caseback that highlights the Advanced Research escapement. The reference was produced in a strictly limited edition of 300 pieces. At the heart of the Ref. 5550P sits the automatic Caliber 240 Q Si — a derivation of Patek’s venerable micro-rotor Cal. 240 Q (perpetual calendar) engineered to incorporate an all-silicon regulating and escapement sub-assembly. Patek grouped the silicon components under the trade name OscilloMax®, which for this Caliber comprises:

• Spiromax® balance spring (silicon)

• Pulsomax® escapement (silicon lever and escape wheel geometry)

• GyromaxSi® balance wheel (a new Silinvar® balance wheel with gold poising weights)

Together these elements replace conventional steel/brass escapement parts and deliver tangible performance benefits: improved energy efficiency, higher isochronism, enhanced resistance to magnetic fields, and a substantially increased power reserve of approximately 70 hours for the 240 Q Si versus the standard 240 Q.