|This high quality Franke sink is a heavy gauge, type 304 (18/10), surgical grade, stainless steel for maximum durability – 18% chromium (for shine) and 10% nickel (for rust resistance) with a titanium coating adhered to the surface of the stainless. The titanium is a combination of titanium and Nitrogen. The process is a thin-film technology with a coating thickness of 2/1000 millimeter (2 u) only. The coating is very hard a 2,600 to 4,200 HV (HV = hardness according to Vicker). As a comparison, gold has a hardness of 240 HV and hard metal one of 1,100 HV.
Recommended Daily Care
Regular cleaning is important to maintain the appearance of your Franke sink.
Wipe with a soft, soapy cloth, rinse and dry after every use. Drying is very important to eliminate any film build-up that may develop from hard water deposits.
Tough Stains and Rust
Most stains are a result of water-borne minerals. Rust stains area result of iron particles from an outside source (i.e., water, cookware, etc.) and can be removed with cleaners containing oxalic acid (such as Bar Keepers Friend®). Steel wool pads leave tiny particles that will develop into rust spots. Stainless steel is, by itself, metallurgically incapable of rusting. Persistent stains, including rust, can be removed with a variety of mild non-abrasive stainless steel cleaners such as Franke’s Inox cream, Shiny Sinks Plus®, Flitz and others. Always rinse thoroughly after using any cleaner.
The significance of the PVD coating is that it is very hard. Our stainless steel has a surface hardness of 400 HV and the coating which we apply one of approx. 3,000. Harder by factor of almost 8 under normal use as a bowl in the kitchen. In spite of this the coating is not brittle and cannot chip even with a massive deformation (dent). The reason for this is that the coating is very thin and that the building up of the structure is stoichiometric (=Stalk structure = one metal ion grows on top of another one.) The coating is only as good as the base material to which it is applied. The coating is “scratch resistant” not indestructible.
What to Avoid
- Bleaches containing hypochlorite will attack stainless steel and cause pitting and staining.
- Silver dip cleaners contain acids that attack stainless steel and leave a permanent stain.
- Certain foods, when left for prolonged periods, can cause pitting and corrosion. Examples are citric fruit juices, salt, vinegar, mustard, pickles, and mayonnaise.
- Strong acids can damage stainless steel (i.e., photographic developing liquids or denture cleanser). If they come in contact with the sink, they should be washed away immediately with clean water
- Scotch Brite pads (green or brown). The coating can be scratched by using either Scotch Brite pad, a saw, a file, granite stone, or anything similar thereby destroying the finish.
There might be a certain abrasion visible when putting cutlery into the bowl. This comes from the cutlery itself since these pieces are usually much softer than our coating. This can be easily removed with a fine detergent.