Manufacturing method of an antimicrobial and adhesion-proof titanium tableware

A manufacturing method of an antimicrobial and adhesion-proof titanium tableware having a contact portion for contacting foods, food ingredients, drinking water, beverages, or body parts of a user, the manufacturing method comprising:

• a preparation step which includes:
• using a titanium substrate to produce a tableware preform;
• an annealing step which includes:
• heating the tableware preform to reach a temperature ranging from 600° C. to 800° C. in a vacuum environment, and maintaining the temperature for 1 hour to 3 hours, so that the tableware preform is annealed and a crystalline structure of α-titanium is formed in the tableware preform;
• a surface treatment step which includes:
• washing a surface of the tableware preform and removing a primary oxidation layer on the surface of the tableware preform;
• an oxidation step which includes:
• placing the tableware preform in a vacuum calcination furnace, heating the tableware preform to reach a temperature ranging from 700° C. to 850° C., and introducing oxygen for allowing one part of the surface of the tableware preform corresponding to the contact portion to be exposed to the oxygen for 3 hours to 12 hours, so that oxygen atoms are combined with titanium atoms of the one part of the surface of the tableware preform corresponding to the contact portion, an oxidation layer structure is formed on the one part of the surface of the tableware preform corresponding to the contact portion, an oxygen diffusion layer is formed at an interface of the oxidation layer structure and the tableware preform, and the tableware preform is further formed into the finished antimicrobial and adhesion-proof titanium tableware;
• a second protective layer disposing step which includes:
• disposing a second protective layer on a surface of the oxidation layer structure that is formed on the one part of the surface of the tableware preform corresponding to the contact portion;
• and
• an outer protective film forming step which includes:
• protecting the oxidation layer structure via the second protective layer, having an outer protective film formed on the another part of the surface of the tableware preform corresponding to the outer portion by thermal oxidation, plasma treatment, or electrochemical treatment, and removing the second protective layer after the outer protective film is formed, wherein the outer protective film is a film made of a titanium-based compound selected from titanium oxide, titanium nitride, or titanium oxynitride,
• wherein the oxidation layer structure is a titanium dioxide film in a rutile crystalline form, a thickness of the oxidation layer structure is greater than 3 μm, a thickness of the oxygen diffusion layer is greater than 1 μm, the oxidation layer structure has a roughened surface, and an arithmetic average roughness (Ra) and a maximum roughness depth (Rmax) of the roughened surface of the oxidation layer structure are greater than 0.2 μm and 0.8 μm, respectively.