I have created corrosion ink and edging ink. It is for "iron, stainless steel, and aluminum."

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It looks like a blue transparent syrup, but it is ink that turns black when it reacts with iron. Once it reacts, it cannot be erased unless you scrape it off. It is what you call a permanent stamp. At the request of our customers, we made it to react with stainless steel. It is a corrosive ink that also reacts with stainless steel. The color resembles a green transparent syrup, but it reacts black. I intended it for stainless steel, but it also reacted with aluminum. It really does turn black when it reacts. Thank you very much as always. I learned a lot this time as well. I will provide sample ink free of charge, so please feel free to contact us. By the way, the ink for iron is ACL-FS, and the one for stainless steel is ACL-SUS.

