PVD vs DLC coatings, which one is the best for a black watch?

When you’re choosing a new wristwatch, especially when you decide a small fortune on some handsome model, you may want to pay attention to its coating. You see, coating isn’t just a stylish caprice that adds to the charm of your watch, but it also determines the look of your watch over time - including aging, scratches and hit marks.

In this article, we’ll mention popular wristwatch coatings and give you more details on each, so you can make a smart decision when buying your first or next black watch. Later, we’ll discuss which of them are most wanted, most expensive and why. But before anything else, let us explain the difference between the watch finish and the watch coating, as some may get confused by the use of terms PVD finish or PVD plated, which are not exactly correct. Let us explain why.

What is watch finish?

Let’s start by explaining what a watch finish is. As the majority of wristwatches are made of stainless steel (and usually come with the default stainless steel watch bands), the finish resembles the way how the top layer of the watch case is processed, in case there is no other material (coating) over the steel.

World class Zaratsu is the mirror polishing process used on all Grand Seiko

There are three most common finishes they usually come with: polished, brushed and blasted.

• The polished finishing is shiny and is most often described as it resembles a mirror. It is made by careful and long polishing process, but it’s probably the most common out there, so there isn’t any specialty or exclusiveness attached to it.
• Brushed watch finish is also called satin coating and means the stainless steel has been polished by using steel brushes and other tools. Hence, you can see tiny lines on the watch case (or even the watch strap). Brushed watch finishes can be done fully or partially, to put an accent on some part of the watch case or a watch band.
• Blasted wristwatch finish barely reflects any light and gives the matte look to the watch. It is made by blasting the watch with tiny glass or sand grains and it is most often found on dive watches.

Three most common metal finishes on watch buckle : polished, brushed and sandblasted

What is watch coating?

Coating means putting some other material over the watches' stainless steel case or turning a top layer of stainless steel case into something else by different processes. The most common coatings are the yellow and rose gold and, in this case, gold is applied to the watch case via process called electrolysis or electrode-plating. For those less familiar with it, simply stated, electrolysis is a process of using a direct electrical current to start a chemical reaction. These coatings are made mostly for decorative use and have no protective function. So, let us head to those coatings that protect the watch case.

As the demand for so called ‘black watch’ (including black metal watch band) is increasing in the past few years, we’ll elaborate two main ways to get that black stainless steel watch look. Aside from the two mentioned below, the black color of the watch can be achieved with methods as simple coloring, powdering, ceramic coating or ion-plating, but we won’t talk about these methods here, as they are usually used on lower-end watches. If you’re looking for the long-term wristwatch protection, the two coating techniques below are the real thing. Take note that these coating methods are not just applied to the watch cases but also to metal watch bands, which explains why you may run across PVD or DLC coated black watch bands or black mesh watch bands, for example.

Seiko Tuna SRPA82K1 Black watch and PVD black stainless steel watch bands by MiLTAT

What is PVD coating?

The first way to get the robust, cool, black watch is to coat the stainless steel with PVD (PVD meaning Physical Vapor Deposition). The process of physical vapor deposition can, in short, be explained as vaporizing the surface of the metal and then turning the vapor back to the metal surface in a vacuum environment. That way, the top layer of the case gets a thin film that serves as a harder, more resistant, protective layer. Due to its ability to improve the durability of the surface to outside influences such as oxidation or shocks, this process is used not only in watchmaking, but also in aeronautics, automotive and optics production. Since the process can be costly, watches with PVD coating are usually somewhat higher in prices compared to those without it, but does it cost justifies the price? Absolutely. Not only will your PVD coated watch last longer, but will be more resistant to environment factors such as scratches, oxidation or temperature. This is especially important in diver watches, where PVD may preserve your watch in harsh sea conditions. When you do a search for, let’s say, black watches for men, you’ll notice that the majority of them are diver timekeepers. As we said, these things are not only for the sake of looks. As this coating layer is very thin, the finish of the metal still usually stays visible beneath it, except that the coating determines the color of the case.

What is DLC coating?

The second method for getting a robust, cool, black watch is the DLC Coating. The DLC stands for Diamond-Like Carbon Coating, which has the same function as PVD - to make the watch case more resistant to environmental factors, but with the significant difference - of doing it much better than the latter. All of it happens because of the difference in the coating process. The DLC is made similar to synthetic diamonds - by blasting carbon particles onto the watches' metal surface - which gives it significantly harder and more resistant protective layer than in case of PVD. As you probably know, diamond is one of the hardest materials on Earth, which may ring some bells on the levels of protection we speak of. This gets the closest to the diamond coating, or better said diamond like coating, as it gets. Therefore, DLC coating is used not only just on diver watches, but in all watches made for all kinds of adventurous activities involving extreme outside conditions, such as watches made for military, explorative or space use. You may have also heard for DLC blades, which is the nickname for the knives with DLC coating on their blades, usually of a military grade.

DLC coating on watch band replacement custom made for Seiko Sumo, Seiko Turtle and Orient Kamasu

PVD vs DLC

Honestly, we at Strapcode didn't get up to the moment where any of our PVD or DLC coated watches gave in, so we don’t have the first-hand experience. It may be just that we're geeks and rarely take our timepieces into extreme conditions. Judging by the forums and user experiences online, PVD is surely less resistant and, especially in case of more active people, wears out much earlier than the DLC coating. How much earlier? We probably speak of years, at least judging by the use of both coating methods in both watchmaking and other areas of use.

When it comes to color, the PVD coating used in watchmaking can be made into gold, rose gold, bronze, blue, dark red and, the most common, black color. Color range for DLC goes from anthracite to deep black. As we know that PVD coating will wear out earlier, some metal color may peek beneath it with time, which probably won't happen anytime soon with DLC, but there’s a price to it. Since DLC coating is much harder, making it bond to a metal surface is a much more complicated process, hence, it is pricier than the PVD.

On the other side, the DLC coating may be less attractive than PVD for some, as it adds somewhat matte-like look to the watch case, which really turns this competition into a taste-deciding. If you don’t expose your watch to extreme conditions too much and care more about the finish and the look of it, then PVD is the way to go. Otherwise, for those of you more interested in extreme longevity of your timepiece, quality DLC coating will keep your watch safe for a lifetime of adventures, hence it will be worth the price.

Take note that, besides buying pre-coated watches, you can also get your stainless steel watch coated in order to customize it and give it more protection. The DLC coating will, again, be more pricier than PVD, but if you’re heading to extreme adventures quite often, it may be well worth the investment.

 SHOP BLACK COATING WATCH BANDS

Written by M.H. , Photo by Toni 

Related topics:

• What is PVD Coating on your wristwatch

External references:

• Wiki/Physical vapor deposition
• Wiki/Diamond like carbon
• Bobswatches.com/../ pvd vs dlc coating worthit
• Bespokeunit.com/../pvd dlc
• Millenarywatches.com/dlc coating watches
• Millenarywatches.com/pvd coating watches
• Johndesmond.com/../what is pvd coating
• Semicore.com/what is pvd coating
• Watchpro.com/.. behind black watches
• Atimelyperspective.com/.. black color pvd dlc ceramic
• Theoandharris.com/.. what is pvd dlc coating
• Watchandbullion.com/watch coating pvd vs dlc
• Wryst-timepieces.com/../pvd and dlc black coating for watches