Inside G&F Châte­lain, the ceram­ics man­u­fac­tur­ing fa­cil­ity of Chanel time­pieces

Revolution (Hong Kong) - - WATCH CULTURE - By Suzanne Wong


he trou­ble with ce­ramic isn’t that it’s brit­tle — its fre­quent pres­ence in var­i­ous ex­ter­nal watch com­po­nents to­day, such as cases, bezels and dial crys­tals, tells us it isn’t so. Nor is the prob­lem that it’s tremen­dously hard to pro­duce in com­plex shapes. Pre­vi­ously, per­haps, this was a con­cern, but one look around you at the var­i­ous ce­ramic time­pieces avail­able now will dis­pel this fal­lacy. Its limited color range? That’s chang­ing as well, and in any case, it’s not as if any other com­pa­ra­ble watch­mak­ing ma­te­rial comes in a rainbow pal­ette. No, the real trou­ble with ce­ramic is that — even now, with ce­ramic watches hav­ing been around since the mid-1980s — no one re­ally knows the first thing about ce­ramic as a ma­te­rial. It doesn’t help that the term en­com­passes so many com­pletely dif­fer­ent def­i­ni­tions. That cof­fee mug on your desk is ce­ramic, just as those ther­mal shields on space shut­tles are. You can ob­tain su­per-hard drill bits made of ce­ramic, just as eas­ily as you can find an ul­tra-ex­pen­sive fine porce­lain din­ner ser­vice (yes, also ce­ramic) that you’ll get screamed at by the other half for putting in the dish­washer. You may not see much of a con­nec­tion be­tween ad­vanced bal­lis­tics body ar­mor and that slop that Pa­trick Swayze and Demi Moore were mess­ing about with in Ghost, but (as you may have guessed by now) they’re both ac­com­plished with ce­ramic ma­te­ri­als. Ce­ramic can be trans­par­ent (sap­phire crys­tal, that is, monocrys­talline alu­minium ox­ide, is a great ex­am­ple) or it can be ut­terly opaque. Its atomic struc­ture can be monocrys­talline, or it can be poly­crys­talline, or it doesn’t have to be crys­talline at all, in which case it is fully amor­phous, and some — though not all — ma­te­ri­als sci­en­tists will gri­mace and state their pref­er­ence for the term “glass” un­der such cir­cum­stances. Therein lies an en­tirely new story, which we can ex­plore some other time when im­me­di­ate som­no­lence is re­quired. If you cut away all the things that it is not, how­ever, then it be­comes rel­a­tively straight­for­ward to iden­tify the tech­ni­cal lim­its of what con­sti­tutes a ce­ramic. A ce­ramic is a non-metal­lic, in­or­ganic solid formed by the ap­pli­ca­tion of heat and sub­se­quent cool­ing. Large boules of sap­phire crys­tal, for ex­am­ple, are formed through heat­ing pure pow­dered alu­mina and oxy­gen in a large fur­nace and al­low­ing it to re­form as a sin­gle crys­tal. Zir­co­nium ox­ide, which is the ma­te­rial used in the vast majority of ce­ramic watch­cases, goes through high-tem­per­a­ture sin­ter­ing in its cru­cial fi­nal stages to ren­der it a dense, ex­tremely hard solid. One of the most con­sis­tently stel­lar man­u­fac­tur­ers of ce­ramic watches is Chanel, with the popular J12 line of time­pieces. Chanel first de­buted the J12 watch in 2000 in black ce­ramic, with a white ver­sion join­ing the col­lec­tion in 2003. Since 2010, Chanel have also in­tro­duced a third color to the black-and-white spec­trum of ce­ramic avail­able for their watches — the metal­lic gray sheen of the J12 Chro­matic. The company that pro­duces the black and white ce­ramic cases and bracelets for Chanel, G&F Châte­lain, was ac­quired by the for­mer in 1993, a key in­vest­ment that would al­low Chanel to con­trol ev­ery as­pect of the fea­ture that de­fined their iconic watch col­lec­tion. Châte­lain is tucked away in the light in­dus­trial area of

La Chaux-de-Fonds, count­ing as its neigh­bors fa­cil­i­ties be­long­ing to other com­pa­nies such as Greubel Forsey, Patek Philippe, Ja­quet Droz, Bre­itling and Cartier. Inside the sprawl­ing in­te­rior of G&F Châte­lain, one of Europe’s most so­phis­ti­cated and ex­pe­ri­enced man­u­fac­ture pro­cesses of zir­co­nium ox­ide ce­ramic takes place. The first step of cre­at­ing the in­cred­i­bly high-per­for­mance and hard­wear­ing ce­ramic cases that house the Chanel J12 is to se­cure the best-qual­ity pre­cur­sor. This in­cludes raw ce­ramic pow­der sourced from Ja­pan and Châte­lain’s own in-house ex­per­tise in blend­ing the ce­ramic pow­der with or­ganic bin­der in a for­mula that is ex­clu­sive to Chanel. The raw ce­ramic ma­te­rial, known as feed­stock, is then shaped us­ing in­jec­tion mold­ing tech­niques into what is known as green forms, and it is the or­ganic bin­der that al­lows the raw ce­ramic pow­der to be thus plas­ti­cally shaped. Th­ese stages have to be ex­tremely care­fully reg­u­lated, as the in­tegrity of the fi­nal ce­ramic prod­uct de­pends largely upon the green ce­ramic form be­ing com­pletely ho­moge­nous in terms of ma­te­rial com­po­si­tion. The green forms un­dergo ma­chin­ing to get them more or less into their fi­nal shapes. This is how ce­ramic cases are now able to hold such com­plex forms, whereas in the past the method of milling cases out of solid ce­ramic blanks was un­der­stand­ably la­bor- and time in­ten­sive, lead­ing to sim­pler case ge­ome­tries. Once the ma­chin­ing is done, the green forms un­dergo de­bind­ing, which leaches the or­ganic ma­te­rial out of the forms and leaves only the ce­ramic in a loose, por­ous ma­trix. At Châte­lain, a pro­pri­etary bin­der for­mula is used so that harm­ful chem­i­cal pro­cesses can be avoided. In this in­stance, the de­bind­ing is ac­com­plished only with wa­ter and heat. Part of the bin­der is leached away in a tem­per­a­ture-con­trolled wa­ter bath, and the rest is elim­i­nated overnight in a 300°C kiln. At this stage, the ce­ramic forms are cu­ri­ously frag­ile, dis­in­te­grat­ing and crum­bling upon the pres­sure of a fin­ger­nail, rather like class­room chalk. The forms are then sin­tered in an oven that is set at 1,200°C. This is where the im­por­tance of get­ting the ini­tial feed­stock for­mula ex­actly right comes to bear. When sin­ter­ing, the ce­ramic un­der­goes den­si­fi­ca­tion and molec­u­lar bond­ing, which means the forms shrink. This shrink­age can be cal­cu­lated very pre­cisely ac­cord­ing to the ra­tios of ce­ramic pow­der to bin­der — typ­i­cally they are cal­cu­lated to shrink at a rate of 20–30 per­cent. Th­ese cal­cu­la­tions are ob­vi­ously es­sen­tial to keep­ing the fi­nal ce­ramic prod­uct within the di­men­sions re­quired by the watch de­sign. The im­por­tance of hav­ing a feed­stock that is per­fectly uni­form, will also tell at this pre­cise stage. Un­evenly dis­trib­uted feed­stock el­e­ments can lead to sec­tions of the green forms be­ing denser than oth­ers, which at the sin­ter­ing stages will cre­ate un­even shrink­age. When the ce­ramic forms emerge from the sin­ter­ing stages, they are in­cred­i­bly hard and dense. Grind­ing and pol­ish­ing — the lat­ter process tak­ing place in a ro­tat­ing drum laced with ce­ramic beads and abra­sive liq­uid con­tain­ing syn­thetic di­a­mond — take them into their fi­nal stages, and they are ready to be as­sem­bled into cases, bracelets or buck­les. By the stan­dards of some other com­pa­nies that have been in the watch­mak­ing business for cen­turies, the his­tory of time­pieces at Chanel may seem rel­a­tively short. How­ever, this hasn’t stopped them from pro­duc­ing some truly ex­cep­tional pieces, such as this year’s J12 Fly­ing Tour­bil­lon with asym­met­ri­cal tour­bil­lon cage. By align­ing their best-sell­ing col­lec­tion — the J12 — with a com­pletely in-house com­pe­tency such as high-tech ceram­ics man­u­fac­ture, Chanel have en­sured their on­go­ing pro­duc­tion of qual­ity, con­tem­po­rary time­pieces.

Chanel care­fully con­trols the raw ma­te­ri­als that go into cre­at­ing the in­cred­i­bly high-per­for­mance and hard-wear­ing ce­ramic cases of the J12 time­pieces The limited- edi­tion J12 In­tense Black fea­tures 724 baguette- cut high-tech ce­ramic pieces that...

Newspapers in English

Newspapers from China

© PressReader. All rights reserved.