The product information of the wristwatch may include the use of "sapphire crystal" or "sapphire glass".What kind of material does this mean?Here, we will introduce the use and characteristics of sapphire glass (officially sapphire crystal), focusing on watches.
What is sapphire glass?
Sapphire glass is a kind of artificial sapphire.Although it is the same composition as a jewel sapphire, it is not a natural jewel, as is artificial.
Here's how sapphire glass is made and what characteristics are.
1枚のサファイアクリスタルでコーティングを変えた写真。右が外側と内側に無反射コーティングを掛けており、中央は片面のみ、左がコーティングなしの状態。Sapphire glass is also an artificially large crystal of high purity aluminum (aluminum oxide).The manufacturing is heated by heating aluminum powder with almost 100%purity and a small amount of iron oxide at a high temperature of 2,000 ° C or higher, and the liquid forms a single crystal.
This single crystal is an artificial sapphire and a sapphire glass.
There are other artificial sapphire manufacturing methods include kiloplus manufacturing, CZ methods, and EFG methods.
The glass is a liquid that is superceded to the viscosity and the same as the individual, which is said to be a non -crystallized state.On the other hand, sapphire glass is a single crystal substance and its structure is different, but it uses the word "glass" for convenience.In the clock, the name of the material is "sapphire crystal", and if it is used in the windshield, it is often used as sapphire glass.
High -purity sapphire crystal is a very good material.It is hard to get scratched and hard to break.In addition, the heat -resistant temperature is very high at 2,000 ° C, and it has a characteristic that it is hard to corrode and has high light permeability.
Gorilla glass is listed as a hard glass material.This is a type of reinforced glass widely used for smartphones and tablets.Using a method of replacing the manufacturing method, the surface strength is said to be several tens of times the plastic.It is manufactured by Corning, a base in Corning, New York.
When a glass material containing sodium (Na) ion is immersed in a potassium (K) ion solution, a small K ion is replaced with a large NA ion, and the K ion fills the gap.It generates strength that cannot easily destroy this ion layer.
Sapphire glass is 9 with a standard "mour hardness" that indicates the hardness, and it is a diamond with a Mohn hardness of 10 that can be damaged.On the other hand, the gorilla glass hardness is 5, and it is easily damaged by the quartz of 7 with the mour hardness 7, which also exists in dust.
現在、もっとも複雑な形状のサファイアクリスタル製風防を装備するのが2019年、オーデマ ピゲから登場した「CODE 11.59 バイ オーデマ ピゲ」だ。角度によって風防は波打つような表情を見せるが、これは内側に施された立体的な削り加工によりつくられる。高度な加工技術により実現した新たな表現手法である。写真は「CODE 11.59 バイ オーデマ ピゲ トゥールビヨン・オープンワーク」。手巻き。19石。2万1600振動／時。パワーリザーブ約80時間。18KPGケース。ケース径41mm、ケース厚10.7mm。時価。In terms of cost, sapphire glass is 5 to 10 times that of gorilla glass.This is the weakness of the Bernoui Law, which takes the energy of combustion reactions and the time for crystal growth.
In addition to this, it is necessary to process sapphire crystal, which is an artificially made stick -shaped crystal (blue).However, it is very difficult to cut and polish due to the strength and hardness that is the characteristic of the material.
Laser cutting equipment requires a process such as cutting out of the boule and then polished with a diamond polished machine, so the product price is higher in proportion to the manufacturing cost.
Sapphire glass as a watch material
Let's look at examples of use on watches based on the characteristics of sapphire glass.A transparent material that protects the clock dial is called "windshield" or "windshield glass".At present, it is a common material that is used as a windshield for many models with more than middle range.
ジャガー・ルクルト「マスター・グランド・トラディショナル・ジャイロ・トゥールビヨン・ウェストミンスター・パーペチュアル」サファイアクリスタルの堅牢性により、裏蓋をシースルー仕様にすることも可能になり、精緻なムーブメントを存分に楽しむことができるようになった。手巻き。126石。2万8800振動／時。パワーリザーブ約52時間。18KWGケース。ケース径43mm、厚さ14mm。3気圧防水。世界限定18本。予価80万ユーロ。Until the 1970s, the windshield was generally plastic.However, plastic is inexpensive and easy to form, and it is difficult to crack, while there is a disadvantage that it is easily damaged and corroded.
Therefore, in the 70's, some manufacturers used mineral glass.This is a so -called general glass and 3 to 6 moars hardness.He was less likely to be damaged than plastic, but was vulnerable to impact, so he did not actively adopt it on luxury watches.It was a material that was not suitable.
In the 1980s, sapphire glass, which is hard to be damaged and hard to break, began to be used.
In modern times, it is generally used for sapphire glass for luxury watches and mineral glass for casual watches.
ウブロ「スピリット オブ ビッグ・バン イエローサファイア」。ウブロではカラードサファイアクリスタルの採用に積極的で、ケースに同素材を使った先駆でもある。最新カラーが写真のイエロー。銅と酸化アルミニウムを融解させることで鮮やかな発色を得ている。自動巻き。31石。3万6000振動／時。パワーリザーブ約50時間。ケース径42mm、厚さ15.2mm。5気圧防水。世界限定100本。1114万円。Sapphire glass may have a reflective coating processing to increase the visibility of the dial.There is a difference between processing only inside or both sides, and when double -sided reflective coating is made, a clear view can be secured almost without light.
However, in the case of double -sided processing, the outer coating may be peeled off, so it is safe to choose one -sided processing if you are concerned about deterioration.
In addition, many models have sapphire glass processed into a dome.This is 5 to 10 times the cost of a flat finish, but it is a commonly used method to give a classic texture of the plastic windshield.
The use of the factory of the processing technology is that some models do not touch the dial three -dimensional decoration, so that only the inside is made into a dome, or a sapphire crystal is adopted for cases and bezels.
ぜんまい知恵袋〜時計の疑問に答えます〜／風防のコーティングについてhttps://www.webchronos.net/features/24931/