This application claims the benefit of priority to Taiwan Patent Application No. 110138296, filed on Oct. 15, 2021. The entire content of the above identified application is incorporated herein by reference.
Some references, which may include patents, patent applications and various publications, may be cited and discussed in the description of this disclosure. The citation and/or discussion of such references is provided merely to clarify the description of the present disclosure and is not an admission that any such reference is “prior art” to the disclosure described herein. All references cited and discussed in this specification are incorporated herein by reference in their entireties and to the same extent as if each reference was individually incorporated by reference.
The present disclosure relates to an antimicrobial and adhesion-proof titanium tableware and a manufacturing method of the same, and more particularly to an antimicrobial and adhesion-proof titanium tableware that is used in drinking water, eating foods, or cooking foods, and a manufacturing method of the same.
Due to the pursuit of a healthy lifestyle, tableware used in modern households is required to be non-toxic and cause zero pollution. Since titanium has the characteristics of light weight, high temperature resistance, corrosion resistance, and low heat conductivity, more and more tableware pieces are made of titanium.
When titanium comes into contact with air, an oxidation layer is formed on a surface of the titanium, and the protective effect of the oxidation layer can improve the wear resistance and corrosion resistance characteristics of titanium tableware. However, a thickness of the oxidation layer naturally generated by titanium in the air is only a few angstroms (Å), so that the oxidation layer is easily worn out. In addition, since a crystalline form of the oxidation layer on the titanium is polycrystalline, the surface of the titanium that has not undergone a surface treatment is matte and has limited catalytic activity, which results in being not adhesion-proof and having limited antimicrobial capability.
For the abovementioned reasons, the antimicrobial and adhesion-proof ability of the titanium tableware is limited and in need of further improvement.
In response to the above-referenced technical inadequacies, the present disclosure provides an antimicrobial and adhesion-proof titanium tableware and a manufacturing method of the same, so as to address insufficient antimicrobial and anti-adhesion properties of existing containers for drinking or eating.
In one aspect, the present disclosure provides an antimicrobial and adhesion-proof titanium tableware. The antimicrobial and adhesion-proof titanium tableware is made of a titanium substrate. The antimicrobial and adhesion-proof titanium tableware includes a contact portion and an oxidation layer structure. The contact portion is used for contacting foods, food ingredients, drinking water, beverages, or body parts of a user. The oxidation layer structure is formed on one part of a surface of the titanium substrate corresponding to the contact portion. The oxidation layer structure is a titanium dioxide film generated by a combination of the titanium substrate and oxygen atoms. The titanium substrate is made of titanium in α phase, and the oxidation layer structure is the titanium dioxide film in a rutile crystalline form that is formed by oxidation of the titanium in α phase. The oxidation layer structure has a roughened surface, and an oxygen diffusion layer is formed at an interface of the oxidation layer structure and the titanium substrate.
In certain embodiments, a thickness of the oxidation layer structure is greater than 3 μm, and a thickness of the oxygen diffusion layer is greater than 1 μm.
In certain embodiments, the oxygen diffusion layer is formed by a solid solution of titanium oxide (TiO) in α phase that is generated by a combination of the oxygen atoms and titanium atoms.
In certain embodiments, an average grain size of the oxidation layer structure is greater than 0.3 μm.
In certain embodiments, 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.
In certain embodiments, the antimicrobial and adhesion-proof titanium tableware further includes an outer portion that is located outside an area of the contact portion and not in contact with the foods, the food ingredients, the drinking water, and the beverages. An outer protective film is formed on another part of the surface of the titanium substrate corresponding to the outer portion, and the outer protective film is formed by technical means different from technical means used to produce the oxidation layer structure, or is formed under processing conditions different from processing conditions from which the oxidation layer structure is produced. The outer protective film is a film made of a titanium-based compound selected from titanium oxide, titanium nitride, or titanium oxynitride.
In another aspect, the present disclosure provides a manufacturing method of an antimicrobial and adhesion-proof titanium tableware. The antimicrobial and adhesion-proof titanium tableware is made of a titanium substrate, and has a contact portion for contacting food, food ingredients, drinking water, beverages, or body parts of a user. The manufacturing method includes a preparation step, an annealing step, a surface treatment step, and an oxidation step. The preparation step includes: using the titanium substrate to produce a tableware preform. The annealing step 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. The surface treatment step includes: washing a surface of the tableware preform and removing a primary oxidation layer on the surface of the tableware preform. The oxidation step 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 in 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. The oxidation layer structure is a titanium dioxide film in a rutile crystalline form, and has a roughened surface. 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.
Therefore, in the antimicrobial and adhesion-proof titanium tableware and the manufacturing method of the same provided by the present disclosure, by virtue of the oxidation layer structure being in the rutile crystalline form, the antimicrobial and anti-adhesion properties of tableware can be improved.
These and other aspects of the present disclosure will become apparent from the following description of the embodiment taken in conjunction with the following drawings and their captions, although variations and modifications therein may be affected without departing from the spirit and scope of the novel concepts of the disclosure.
The described embodiments may be better understood by reference to the following description and the accompanying drawings, in which:
The present disclosure is more particularly described in the following examples that are intended as illustrative only since numerous modifications and variations therein will be apparent to those skilled in the art. Like numbers in the drawings indicate like components throughout the views. As used in the description herein and throughout the claims that follow, unless the context clearly dictates otherwise, the meaning of “a”, “an”, and “the” includes plural reference, and the meaning of “in” includes “in” and “on”. Titles or subtitles can be used herein for the convenience of a reader, which shall have no influence on the scope of the present disclosure.
The terms used herein generally have their ordinary meanings in the art. In the case of conflict, the present document, including any definitions given herein, will prevail. The same thing can be expressed in more than one way. Alternative language and synonyms can be used for any term(s) discussed herein, and no special significance is to be placed upon whether a term is elaborated or discussed herein. A recital of one or more synonyms does not exclude the use of other synonyms. The use of examples anywhere in this specification including examples of any terms is illustrative only, and in no way limits the scope and meaning of the present disclosure or of any exemplified term. Likewise, the present disclosure is not limited to various embodiments given herein. Numbering terms such as “first”, “second” or “third” can be used to describe various components, signals or the like, which are for distinguishing one component/signal from another one only, and are not intended to, nor should be construed to impose any substantive limitations on the components, signals or the like.
Referring to
As shown in
In this embodiment, the antimicrobial and adhesion-proof titanium tableware 1 is a cup for holding drinking water or beverages. A concave-shaped holding space 13 is formed inside the antimicrobial and adhesion-proof titanium tableware 1, and can be used for holding drinking water, beverages, or foods. The contact portion 11 is formed on a surface of the holding space 13 inside the antimicrobial and adhesion-proof titanium tableware 1. For the antimicrobial and adhesion-proof titanium tableware 1, the oxidation layer structure 12 is at least formed on the one part of the surface of the titanium substrate 10 corresponding to the contact portion 11.
It should be noted that, although the antimicrobial and adhesion-proof titanium tableware 1 is the cup in this embodiment, the present disclosure is not limited thereto. For example, in the embodiment shown in
As shown in
As shown in
In the embodiment shown in
It should be noted that, in addition to those described in the abovementioned embodiments, the antimicrobial and adhesion-proof titanium tableware 1 of the present disclosure can be other types of tableware. For example, the antimicrobial and adhesion-proof titanium tableware 1 can also be a knife, a spoon, a spatula, a tea strainer, or tableware of other types.
The following description relates to the oxidation layer structure 12 on a surface of the antimicrobial and adhesion-proof titanium tableware 1 of the present disclosure. As shown in
Since the rutile type of titanium dioxide is a crystalline form with high stability, and the rutile type of titanium dioxide has a high specific surface area (as calculated by using Brunauer-Emmett-Teller (BET) theory), the oxidation layer structure 12 has good photocatalytic activity, and the photocatalytic activity thereof is stable and not easily decayed. In addition, since the oxidation layer structure 12 is a film that is ceramicized and has a crystalline form, characteristics of the oxidation layer structure 12 include having a high hardness, being abrasion resistant, and being anti-sticking. Therefore, the antimicrobial and adhesion-proof titanium tableware 1 of the present disclosure is not easily scratched, and foods or drinks are not easily adhered to the surface of the contact portion 11, so as to achieve effects of anti-adhesion and pollution reduction.
In more detail, the oxidation layer structure 12 of the present disclosure is formed on the one part of the surface of the titanium substrate 10 corresponding to the contact portion 11 by a thickness greater than a thickness of a primary oxidation layer made of titanium, and the oxidation layer structure 12 of the present disclosure has a roughened surface 121. In an exemplary embodiment of the present disclosure, the thickness of the oxidation layer structure 12 is greater than 3 μm, and an average grain size of the oxidation layer structure 12 is greater than 0.3 μm. Further, an arithmetic average roughness (Ra) and a maximum roughness depth (Rmax) of the roughened surface 121 are greater than 0.2 μm and 0.8 μm, respectively.
Since the thickness of the oxidation layer structure 12 is far greater than the thickness of the primary oxidation layer naturally formed on the surface of the titanium metal, the oxidation layer structure 12 has a large crystalline grain size, and gaps are easily formed in the crystal lattice. Furthermore, since the oxidation layer structure 12 has the roughened surface 121, a surface of the oxidation layer structure 12 is roughened and in a jagged shape, so that the oxidation layer structure 12 can have an increased contact area and a better catalytic activity.
Furthermore, as shown in
The oxygen diffusion layer 122 is tightly bonded between the titanium substrate 10 and the oxidation layer structure 12. A density of the oxygen diffusion layer 122 is greater than that of the oxidation layer structure 12, and a hardness of the oxygen diffusion layer 122 is greater than that of the oxidation layer structure 12. Therefore, corrosion of titanium substrate 10 can be effectively prevented, and the bonding between the oxidation layer structure 12 and the titanium substrate 10 is more stable.
The manufacturing method of the antimicrobial and adhesion-proof titanium tableware of the present disclosure is described as follows. As shown in
As shown in
The annealing step S120 includes: removing, after the tableware preform 40 is processed, residual stresses through processes of heating and slow cooling, so that a crystalline structure of α-titanium is formed in the tableware preform 40. In more detail, the annealing step S120 is to place the tableware preform 40 in a vacuum calcination furnace, so that the tableware preform 40 is placed in a vacuum environment and heated to reach a temperature ranging from 600° C. to 800° C. The temperature is maintained for 1 hour to 3 hours, so that the tableware preform 40 is annealed and a crystalline structure of α-titanium is formed in the tableware preform 40.
As shown in
In this embodiment of the present disclosure, the surface treatment step S130 can further include a roughening sub-step S133, through which one part of the surface of the tableware preform 40 corresponding to the contact portion 11 and predetermined to form the oxidation layer structure 12 has an increased surface roughness and is formed into a roughened surface. For example, the roughening sub-step S133 can treat the one part of the surface of the tableware preform 40 that is predetermined to form the oxidation layer structure 12 by acid etching and sandblasting, so that the surface of the tableware preform 40 is roughened.
Particularly, although the surface treatment step S130 in this embodiment is arranged after the annealing step S120, the surface treatment step S130 can also be arranged before the annealing step S120 in other embodiments of the present disclosure.
Through the oxidation step S140, the oxygen atoms are combined with the titanium atoms of the one part of the surface of the tableware preform 40 corresponding to the contact portion 11, so that the oxidation layer structure 12 and the oxygen diffusion layer 122 are formed, and the tableware preform 40 is further formed into a finished product of the antimicrobial and adhesion-proof titanium tableware 1.
Reference is made to
As shown in
In the oxidation step S140, firstly, a titanium surface of the tableware preform 40 adsorbs oxygen atoms from the decomposition of oxygen gas, and then the oxygen atoms diffuse in a titanium lattice. When the oxygen atoms reach saturation in the titanium lattice, titanium oxide is formed on the surface of the tableware preform 40. As the oxidation continues, an oxidation layer gradually becomes thicker to form into the oxidation layer structure 12. The oxidation step S140 continues to allow the oxygen atoms to pass through the oxidation layer structure 12, and the titanium dioxide located at an inner side of the oxidation layer structure 12 can form anoxic titanium dioxide due to continuous heating and lack of oxygen. Further, a portion of the oxygen atoms are dissociated and penetrate into the titanium atoms of the titanium substrate 10, which results in formation of the oxygen diffusion layer 122.
Upon completion of the oxidation step S140, the oxidized tableware preform 40 can form into the finished product of the antimicrobial and adhesion-proof titanium tableware 1. The antimicrobial and adhesion-proof titanium tableware 1 has the oxidation layer structure 12 that is titanium dioxide in the rutile crystalline form formed on the surface of the titanium substrate 10 and the oxygen diffusion layer 122 that is located at the inner side of the oxidation layer structure 12.
In more detail, through controlling of an oxidation temperature and an oxidation duration, the oxidation step S140 of the present disclosure is capable of achieving the following goals: the thickness of the oxidation layer structure 12 being greater than 3 μm, the average grain size of the oxidation layer structure 12 being greater than 0.3 μm, the oxidation layer structure 12 having the roughened surface 121, and the arithmetic average roughness (Ra) and the maximum roughness depth (Rmax) of the roughened surface 121 being greater than 0.2 μm and 0.8 μm, respectively.
In this embodiment, the oxidation temperature of the oxidation step S140 ranges from 700° C. to 850° C., and the oxidation duration is between 3 hours and 12 hours. Particularly, the oxidation temperature and the oxidation duration in the oxidation step S140 of this embodiment can be used to control the thickness of the oxidation layer structure 12. As the oxidation temperature gets higher and the oxidation duration gets longer, a surface roughness and a surface porosity of the oxidation layer structure 12 can be increased. However, it should be noted that the oxidation temperature needs to be lower than a temperature at a transformation point of the titanium substrate 10 that transforms from α phase to β phase, and the oxidation duration needs to be shorter than a critical time at which the oxidation layer structure 12 has a flaking phenomenon.
By the abovementioned arrangements, in the oxidation step S140 of the present disclosure, the oxidation layer structure 12 formed on the surface of the titanium substrate 10 can be made of stable titanium dioxide in the rutile crystalline form, and the thickness and the surface roughness of the oxidation layer structure 12 can be as expected. Moreover, after the oxidation layer structure 12 is formed, the oxygen diffusion layer 122 can further be formed at the interface of the inner side of the oxidation layer structure 12 and the titanium substrate 10.
As shown in
In the oxidation step S140, the tableware preform 40 is placed into the vacuum chamber 36, so that the tableware preform 40 is positively charged. The oxygen gas passes through the ion generation device 35 by entering the inlet tube 33, so that the oxygen gas is transformed into a plasma state having separated atoms and electrons. The oxygen atoms in the oxygen gas are ions that are positively charged. Accordingly, when the plasma gas is in contact with the tableware preform 40, electrons of the oxygen ions are attached to the positively charged titanium and cause electron attachment, so that the titanium atoms of the titanium on the surface of the tableware preform 40 are tightly bonded with the negatively charged oxygen ions to form the oxidation layer structure 12.
In this embodiment, the oxidation step S140 is to oxidize the surface of the tableware preform 40 in the vacuum chamber 36 (which is a vacuum environment of 5.0×10−3 Torr) with an oxygen flow rate of 30 sccm and a power ranging from 200 W to 300 W. In addition, the oxidation duration ranges from 1 hour to 3 hours.
As shown in
In this embodiment, the antimicrobial and adhesion-proof titanium tableware 1 has an outer portion 16 that is located outside an area of the contact portion 11 and not in contact with the foods, the food ingredients, the drinking water, or the beverages, and an outer protective film 17 is formed on another part of the surface of the titanium substrate 10 corresponding to the outer portion 16. The outer protective film 17 is formed on a surface of the outer portion 16 of the antimicrobial and adhesion-proof titanium tableware 1 by technical means different from technical means used to produce the oxidation layer structure 12, or is formed under processing conditions different from processing conditions from which the oxidation layer structure 12 is produced, so as to protect the titanium substrate 10 at the outer portion 16 from corrosion and abrasion. Moreover, the outer protective film 17 can also be a decorative film having a decorative function.
In more detail, the outer protective film 17 can be formed on the surface of the outer portion 16 of the antimicrobial and adhesion-proof titanium tableware 1 by using ionic oxidation, micro-arc oxidation, electrochemical treatment, and other technical means, or thermal oxidation having the processing conditions different from the processing conditions from which the oxidation layer structure 12 is produced after the oxidation layer structure 12 is formed. The outer protective film 17 can be a film made of a titanium-based compound selected from titanium oxide, titanium nitride, or titanium oxynitride. The outer protective film 17 has a high density, and the outer protective film 17 can have different light reflection rates and produce visual effects of different colors, so as to achieve the effect of improving the aesthetic appearance of the antimicrobial and adhesion-proof titanium tableware 1.
Since the manufacturing method of the second embodiment of the present disclosure is similar to the manufacturing method of the first embodiment, similarities therebetween will not be reiterated herein.
As shown in
The manufacturing method S200 of this embodiment further includes a first protective layer disposing step S240 arranged before the oxidation step S250, and a first protective layer removal step S260, a second protective layer disposing step S270, and an outer protective film forming step S280 that are arranged after the oxidation step S250.
The first protective layer disposing step S240 is to dispose a first protective layer (not shown in the figures) on the another part of the surface of the tableware preform 40 corresponding to the outer portion 16. The first protective layer can cover the another part of the surface of the tableware preform 40 corresponding to the outer portion 16, so that the another part of the surface of the tableware preform 40 corresponding to the outer portion 16 does not react with oxygen during the oxidation step S250, thereby allowing the oxidation layer structure 12 to be formed only on the one part of the surface of the tableware preform 40 corresponding to the contact portion 11.
The first protective layer removal step S260 is to remove the first protective layer from the surface of the tableware preform 40 after the oxidation step S250 is completed, so that the another part of the surface of the tableware preform 40 corresponding to the outer portion 16 is exposed.
The second protective layer disposing step S270 is to dispose a second protective layer (not shown in the figures) on the one part of the surface of the tableware preform 40 corresponding to the contact portion 11 and the oxidation layer structure 12 after the oxidation step S250 is completed, and the second protective layer can cover the surface of the oxidation layer structure 12. The second protective layer is used to protect the oxidation layer structure 12 in the subsequent outer protective film forming step S280, so as to prevent the oxidation layer structure 12 from being damaged or contaminated in the outer protective film forming step S280.
The outer protective film forming step S280 is to protect the oxidation layer structure 12 via the second protective layer, to form the outer protective film 17 on the another part of the surface of the tableware preform 40 corresponding to the outer portion 16 by thermal oxidation, plasma treatment, micro-arc oxidation, or electrochemical treatment, and to remove the second protective layer after the outer protective film 17 is formed.
The second embodiment of the manufacturing method of the present disclosure is characterized in that the outer protective film 17 is formed by technical means other than technical means used to produce the oxidation layer structure 12, so that films made of different types of titanium-based compounds (e.g., titanium oxide, titanium nitride, titanium oxynitride) can be used according to requirements. In this way, the oxidation layer structure 12 and the outer protective film 17 can have different characteristics. Furthermore, when the outer protective film 17 is being formed, the oxidation layer structure 12 of the contact portion 11 is protected by the second protective layer and is not exposed to the working gas or liquid used in the outer protective film forming step S280. Accordingly, the oxidation layer structure 12 can be prevented from being damaged due to having reaction with the working gas or liquid, and can also be prevented from being contaminated by the working gas or liquid.
One of the beneficial effects of the present disclosure is that, in the antimicrobial and adhesion-proof titanium tableware and the manufacturing method of the same provided by the present disclosure, by virtue of “an oxidation layer structure being formed on a surface of the titanium substrate,” “the oxidation layer structure being a titanium dioxide film in a rutile crystalline form,” and “the oxidation layer structure having a roughened surface,” the oxidation layer structure has good, long-lasting and stable catalytic activity, so that the antimicrobial and adhesion-proof titanium tableware of the present disclosure can effectively inhibit the growth of microorganisms. Furthermore, a crystallized and ceramicized surface is formed on the antimicrobial and adhesion-proof titanium tableware to have the adhesion-proof property.
The foregoing description of the exemplary embodiments of the disclosure has been presented only for the purposes of illustration and description and is not intended to be exhaustive or to limit the disclosure to the precise forms disclosed. Many modifications and variations are possible in light of the above teaching.
The embodiments were chosen and described in order to explain the principles of the disclosure and their practical application so as to enable others skilled in the art to utilize the disclosure and various embodiments and with various modifications as are suited to the particular use contemplated. Alternative embodiments will become apparent to those skilled in the art to which the present disclosure pertains without departing from its spirit and scope.
Number | Date | Country | Kind |
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110138296 | Oct 2021 | TW | national |
Number | Date | Country |
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113260734 | Aug 2021 | CN |
216569396 | May 2022 | CN |
200181544 | Mar 2001 | JP |
2020183551 | Nov 2020 | JP |
WO2020223376 | Nov 2020 | WO |
Entry |
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Machine Translation of CN 216569396 (Year: 2022). |
Number | Date | Country | |
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20230123871 A1 | Apr 2023 | US |