Tokunaga on: sapphire vs Hardlex
Authored by petew
I recently emailed Tokunaga about the use of Sapphire in the new 1000M. His response cleared some misconceptions that I and others have been under the assumption of over the past few years. (Ed Rader..you now can say "I told you so."
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Here was his very illuminating response to my question: "I see that Seiko will use sapphire glass in the new 1000M diver. Are you now confident that sapphire is a better material than hardlex?"
First of all, if you have misunderstood because of my shortage of explanation at the last glass explanation on the S&C Forum, I must apologize to you for it. What I meant at the explanation is the reason why Seiko has adopted high-quality Hardlex on 1000m professional diver’s watch is that “cost performance is excellent.” I never said that high-quality Hardlex surpasses Sapphire on the performance of the material itself. And I meant that the loss-rate rises high in case of making a larger and thicker Sapphire glass, as a reason the cost of Sapphire is high.
http://www.network54.com/Forum/message?forumid=78440&messageid=1037842045
OK, I would explain the meaning more concretely.
The resistance to pressure which SEIKO1000m is virtually asked is at least 2000m or more. High-quality Hardlex of 4mm thickness adopted on 1000m clears this standard. On the other hand, in order to secure the resistance to pressure as same level as that of high-quality Hardlex (4mm) by using Sapphire, the thickness of about 3mm is required. Although both performances are same grade, Sapphire (3mm) is higher about the cost, therefore high-quality Hardlex (4mm) is superior to Sapphire (3mm). -- Incidentally, the thickest Sapphire that SEIKO uses now is less than 3mm. The resistance to pressure of Sapphire (less than 3mm) is inferior to that of high-quality Hardlex (4mm) --
Then, how about the Sapphire of 4mm thickness? Compared with the cost of high-quality Hardlex (4mm), that of Sapphire (4mm) rises very high. However, about the resistance to pressure and the durability of Sapphire (4mm), it exceeds that of high-quality Hardlex (4mm). In order for Sapphire (4mm) to exceed high-quality Hardlex (4mm) also at the point of cost performance, we have needed to reduce the manufacture cost of Sapphire (4mm) further.
In recent years, with producing various kinds of PROSPEX watches, the adoption of Sapphire glass has been promoted, and so many Sapphire glasses of 2mm or more thickness can be manufactured stably. By the improvement of manufacture technology which is related to it, SEIKO has succeeded in reducing the manufacture cost of Sapphire (4mm) to a half of that of 1986. And this time, this Sapphire (4mm) has been carried on new 1000m professional diver’s watch.
One of the key concepts of the SEIKO’s watch making is "The highest cost performance watch in the world." As I mentioned before, SEIKO 1000m professional diver’s watch is one of a few saturation diving specifications watches in the world, and has the highest water-tightness and the air-tightness at a price of about 130,000 yen.
By this time’s model change, user’s cost goes up about 30,000 yen, but I judged that the cost performance of the new model exceeded that of the present model, by considering synthetically the merits, such as the further improvement of resistance to pressure and durability, the materials of the world highest performance, user’s attachment to Sapphire glass, and the other various elements.
At the meaning above, yes, I am confident that Sapphire is better than Hardlex.
Sorry for the long message, but I hope this is helpful for you and other S&C Forumers.
Sincerely yours,
Ikuo Tokunaga
Authored by petew
I recently emailed Tokunaga about the use of Sapphire in the new 1000M. His response cleared some misconceptions that I and others have been under the assumption of over the past few years. (Ed Rader..you now can say "I told you so."
Here was his very illuminating response to my question: "I see that Seiko will use sapphire glass in the new 1000M diver. Are you now confident that sapphire is a better material than hardlex?"
First of all, if you have misunderstood because of my shortage of explanation at the last glass explanation on the S&C Forum, I must apologize to you for it. What I meant at the explanation is the reason why Seiko has adopted high-quality Hardlex on 1000m professional diver’s watch is that “cost performance is excellent.” I never said that high-quality Hardlex surpasses Sapphire on the performance of the material itself. And I meant that the loss-rate rises high in case of making a larger and thicker Sapphire glass, as a reason the cost of Sapphire is high.
http://www.network54.com/Forum/message?forumid=78440&messageid=1037842045
OK, I would explain the meaning more concretely.
The resistance to pressure which SEIKO1000m is virtually asked is at least 2000m or more. High-quality Hardlex of 4mm thickness adopted on 1000m clears this standard. On the other hand, in order to secure the resistance to pressure as same level as that of high-quality Hardlex (4mm) by using Sapphire, the thickness of about 3mm is required. Although both performances are same grade, Sapphire (3mm) is higher about the cost, therefore high-quality Hardlex (4mm) is superior to Sapphire (3mm). -- Incidentally, the thickest Sapphire that SEIKO uses now is less than 3mm. The resistance to pressure of Sapphire (less than 3mm) is inferior to that of high-quality Hardlex (4mm) --
Then, how about the Sapphire of 4mm thickness? Compared with the cost of high-quality Hardlex (4mm), that of Sapphire (4mm) rises very high. However, about the resistance to pressure and the durability of Sapphire (4mm), it exceeds that of high-quality Hardlex (4mm). In order for Sapphire (4mm) to exceed high-quality Hardlex (4mm) also at the point of cost performance, we have needed to reduce the manufacture cost of Sapphire (4mm) further.
In recent years, with producing various kinds of PROSPEX watches, the adoption of Sapphire glass has been promoted, and so many Sapphire glasses of 2mm or more thickness can be manufactured stably. By the improvement of manufacture technology which is related to it, SEIKO has succeeded in reducing the manufacture cost of Sapphire (4mm) to a half of that of 1986. And this time, this Sapphire (4mm) has been carried on new 1000m professional diver’s watch.
One of the key concepts of the SEIKO’s watch making is "The highest cost performance watch in the world." As I mentioned before, SEIKO 1000m professional diver’s watch is one of a few saturation diving specifications watches in the world, and has the highest water-tightness and the air-tightness at a price of about 130,000 yen.
By this time’s model change, user’s cost goes up about 30,000 yen, but I judged that the cost performance of the new model exceeded that of the present model, by considering synthetically the merits, such as the further improvement of resistance to pressure and durability, the materials of the world highest performance, user’s attachment to Sapphire glass, and the other various elements.
At the meaning above, yes, I am confident that Sapphire is better than Hardlex.
Sorry for the long message, but I hope this is helpful for you and other S&C Forumers.
Sincerely yours,
Ikuo Tokunaga
