Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C17/00—Preparation of halogenated hydrocarbons
  • C07C17/25—Preparation of halogenated hydrocarbons by splitting-off hydrogen halides from halogenated hydrocarbons
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C17/00—Preparation of halogenated hydrocarbons
  • C07C17/35—Preparation of halogenated hydrocarbons by reactions not affecting the number of carbon or of halogen atoms in the reaction
  • C07C17/357—Preparation of halogenated hydrocarbons by reactions not affecting the number of carbon or of halogen atoms in the reaction by dehydrogenation
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C23/00—Compounds containing at least one halogen atom bound to a ring other than a six-membered aromatic ring
  • C07C23/02—Monocyclic halogenated hydrocarbons
  • C07C23/06—Monocyclic halogenated hydrocarbons with a four-membered ring
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
  • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
  • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
  • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
  • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
  • H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
  • H01L21/302—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to change their surface-physical characteristics or shape, e.g. etching, polishing, cutting
  • H01L21/306—Chemical or electrical treatment, e.g. electrolytic etching
  • H01L21/3065—Plasma etching; Reactive-ion etching

Definitions

• the present disclosure relates to a method for producing cyclobutene.
• Cyclobutene containing a halogen atom is a compound useful as a dry etching gas for semiconductors, various refrigerants, foaming agents, heat transfer media, and the like.
• 1H-pentafluorocyclobutene is known to be a method for producing 1H-pentafluorocyclobutene from 1H,2H-hexafluorocyclobutane by dehydrofluorination reaction (for example, Non-Patent Documents 1 and 2).
• This technology synthesizes 1H-pentafluorocyclobutene in an open reaction system using glassware.
• the present disclosure aims to produce cyclobutene containing a halogen atom with high selectivity.
• the present disclosure includes the following configurations.
• X 1 , X 2 , X 3 , X 4 and Y are the same as above.
• X 5 and X 6 are the same or different and each represents a hydrogen atom, a halogen atom or a perfluoroalkyl group. .) Including a step of removing cyclobutane represented by A manufacturing method, wherein the step of performing the elimination reaction is performed in a gas phase.
• Item 2 The production method according to Item 1, wherein X 5 is a hydrogen atom, X 6 is a halogen atom, and the elimination reaction is a dehydrohalogenation reaction.
• Item 4 The content of 1H-perfluorocyclobutene (1H-cC 4 F 5 H) is 99 mol% or more, the content of 3H-perfluorocyclobutene (3H-cC 4 F 5 H) is 1 mol% or less, Item 4.
• Item 5. The composition according to Item 3 or 4, which is used as a cleaning gas, an etching gas, a deposit gas, or a building block for organic synthesis.
• cyclobutene containing a halogen atom can be produced with high selectivity.
• the inventors of the present invention performed a step of eliminating a raw material compound in a gas phase to obtain cyclobutene containing a halogen atom represented by the general formula (1) with high selectivity. It was found that it can be manufactured.
• the present disclosure includes the following embodiments.
• X 1 , X 2 , X 3 , X 4 and Y are the same as above.
• X 5 and X 6 are the same or different and each represents a hydrogen atom, a halogen atom or a perfluoroalkyl group. .
• the step of performing the elimination reaction is performed in the gas phase.
• cyclobutene containing a halogen atom can be produced with high selectivity.
• the “selectivity” refers to the target compound (halogen atom is included in the effluent gas with respect to the total molar amount of compounds other than the raw material compound (cyclobutene containing a halogen atom) in the effluent gas from the reactor outlet. (Including cyclobutene) means the ratio (mol %) of the total molar amount.
• the “conversion rate” means a compound other than the raw material compound (halogen atom is included in the outflow gas from the reactor outlet, with respect to the molar amount of the raw material compound (cyclobutane containing a halogen atom) supplied to the reactor. (Including cyclobutene, etc.) means the ratio (mol%) of the total molar amount.
• the method for producing cyclobutene according to the present disclosure has a merit that it is not a batch reaction but a gas phase reaction of a distribution system, and therefore a solvent is not required and industrial waste does not occur.
• Raw material compound In the present disclosure, the raw material compound is represented by the general formula (2):
• X 1 , X 2 , X 3 , X 4 , X 5 and X 6 are the same or different and represent a hydrogen atom, a halogen atom or a perfluoroalkyl group.
• Y represents a halogen atom.
• X 1 , X 2 , X 3 , X 4 , X 5 and X 6 are the same or different and each represents a hydrogen atom, a halogen atom or a perfluoroalkyl group.
• Y represents a halogen atom
• Examples of the halogen atom of X 1 , X 2 , X 3 , X 4 , X 5 , X 6 and Y include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.
• the perfluoroalkyl group of X 1 , X 2 , X 3 , X 4 , X 5 and X 6 is an alkyl group in which all hydrogen atoms are replaced by fluorine atoms.
• the perfluoroalkyl group is, for example, a perfluoroalkyl group having 1 to 20 carbon atoms, preferably 1 to 12 carbon atoms, more preferably 1 to 6 carbon atoms, further preferably 1 to 4 carbon atoms, particularly preferably 1 to 3 carbon atoms. It is preferably a fluoroalkyl group.
• the perfluoroalkyl group is preferably a linear or branched perfluoroalkyl group.
• the perfluoroalkyl group is preferably a trifluoromethyl group (CF 3 -) and a pentafluoroethyl group (C 2 F 5 -).
• cyclobutane containing a halogen atom represented by the general formula (2) which is a raw material compound
• X 1 , X 2 , X 3 and X 4 are the same or different and each independently represent a hydrogen atom, a halogen atom or a perfluoroalkyl group
• X 5 is a hydrogen atom
• X 6 is a fluorine atom
• Y is more preferably a fluorine atom.
• cyclobutane represented by the general formula (2) which is a raw material compound, include:
• the cyclobutane represented by the general formula (2) can be used alone or in combination of two or more kinds. As such cyclobutane, a commercially available product can be adopted.
• X 1 , X 2 , X 3 , X 4 and X 6 are, in that cyclobutene containing a halogen atom can be produced with high selectivity. More preferably, it is a fluorine atom, X 5 is a hydrogen atom, and Y is a fluorine atom.
• the elimination reaction is performed in a gas phase.
• the step of the desorption reaction in the present disclosure is preferably carried out in a gas phase, particularly preferably in a gas phase continuous flow system using a fixed bed reactor.
• the apparatus, operation, etc. can be simplified, and it is economically advantageous.
• X 5 is a hydrogen atom
• X 6 is a halogen atom
• the elimination reaction is a dehydrohalogenation reaction.
• X 5 is a hydrogen atom
• X 6 is a fluorine atom
• the elimination reaction is a dehydrofluorination reaction.
• X 1 , X 2 , X 3 , X 4 and X 6 are fluorine atoms and X 5 is a hydrogen atom.
• Y is preferably a fluorine atom.
• the elimination reaction is preferably a dehydrofluorination reaction.
• Catalyst In the step of the elimination reaction in the present disclosure, it is preferable to perform the elimination reaction in the gas phase in the presence of a catalyst.
• the catalyst used in this step is preferably activated carbon.
• the catalyst used in this step is preferably a metal catalyst.
• a metal catalyst chromium oxide, chromium fluoride oxide, chromium fluoride, aluminum oxide, aluminum fluoride oxide, aluminum fluoride, iron oxide, iron oxide fluoride, iron fluoride, nickel oxide, nickel fluoride oxide, fluoride It is preferably at least one selected from the group consisting of nickel, magnesium oxide, magnesium fluoride oxide and magnesium fluoride.
• activated carbon, chromium oxide, chromium fluoride oxide, aluminum oxide, and aluminum fluoride oxide are more preferable because the target compound can be obtained with higher selectivity. It is also possible to further improve the conversion rate of the raw material compound.
• the catalyst may be in powder form, but pellet form is preferable for gas phase continuous flow reaction.
• the specific surface area of the catalyst measured by the BET method (hereinafter, also referred to as BET specific surface area) is usually 10 to 3,000 m 2 /g, preferably 10 to 400 m 2 /g, and more preferably 20 to 375 m. 2 /g, more preferably 30 to 350 m 2 /g.
• BET specific surface area of the catalyst is in such a range, the density of the catalyst particles is not too small, and thus the target compound can be obtained with high selectivity. It is also possible to improve the conversion rate of the raw material compound.
• powdered activated carbon such as crushed coal, shaped coal, granulated coal, spherical charcoal.
• powdered activated carbon it is preferable to use powdered activated carbon having a particle size of 4 mesh (4.76 mm) to 100 mesh (0.149 mm) in the JIS test.
• a metal catalyst When a metal catalyst is used as the catalyst, it is preferably supported on a carrier.
• the carrier include carbon, alumina (Al 2 O 3 ), zirconia (ZrO 2 ), silica (SiO 2 ), titania (TiO 2 ), and the like.
• carbon activated carbon, amorphous carbon, graphite, diamond or the like can be used.
• Chromium oxide and fluorinated chromium oxide will be described as an example of the catalyst in the present disclosure.
• chromium oxide for example, when chromium oxide is represented by Cr 2 O 3 .nH 2 O, the value of n is preferably 3 or less, more preferably 1 to 1.5.
• the chromium oxide is preferably one in which m is usually in the range of 1.5 ⁇ m ⁇ 3.
• fluorinated chromium oxide can be prepared by fluorinating chromium oxide. Examples of the fluorination include fluorination with hydrogen fluoride (HF) and fluorination with fluorocarbon and the like.
• Fluorinated chromium oxide as a catalyst can be obtained, for example, according to the method described in Japanese Patent No. 3412165.
• a fluorinated chromium oxide can be obtained by fluorinating chromium oxide with hydrogen fluoride (HF treatment).
• the fluorination temperature is preferably 100 to 460° C., for example.
• the pressure for fluorination is preferably the pressure at which it is subjected to a catalytic reaction.
• the highly fluorinated-chromium oxide catalyst can be obtained by fluorinating chromium oxide at a higher temperature than usual for a long time.
• the highly fluorinated-chromium oxide catalyst preferably has a fluorine content of 30% by mass or more, more preferably 30 to 45% by mass.
• the fluorine content can be measured by a mass change of the catalyst or a general quantitative analysis method of chromium oxide.
• the lower limit of the reaction temperature is such that the elimination reaction proceeds more efficiently and the target compound can be obtained with higher selectivity, and the conversion rate decreases. From the viewpoint of suppressing the above, it is usually 50° C., preferably 200° C., more preferably 250° C., further preferably 300° C., particularly preferably 350° C.
• the upper limit of the reaction temperature in the elimination reaction is selected from the viewpoint that the dehydrofluorination reaction can proceed more efficiently and the target compound can be obtained with higher selectivity, and that the reaction product decomposes or polymerizes. From the viewpoint of suppressing the decrease in the rate, it is usually 500° C., preferably 450° C., and more preferably 400° C.
• the reaction time of the desorption reaction is defined as the contact time of the starting compound with the catalyst (W/F 0 )[W: weight of metal catalyst (g), F 0 : flow rate of starting compound (cc/sec)] If the length is increased, the conversion rate of the raw material compound can be increased, but the amount of the catalyst is increased and the equipment becomes large, which is inefficient.
• the reaction time of the dehydrofluorination reaction is 5 g ⁇ sec for the contact time (W/F 0 ) of the raw material compound with the catalyst from the viewpoint of improving the conversion rate of the raw material compound and suppressing the equipment cost.
• /Cc to 300 g ⁇ sec/cc is preferable, 10 g ⁇ sec/cc to 200 g ⁇ sec/cc is more preferable, 15 g ⁇ sec/cc to 150 g ⁇ sec/cc is further preferable, It is particularly preferable that it is 20 g ⁇ sec/cc to 100 g ⁇ sec/cc.
• the contact time of the raw material compound with the catalyst means the time of contact between the raw material compound and the catalyst.
• the reaction temperature and the reaction time are appropriately adjusted particularly according to the catalyst, so that the target compound can be obtained with higher selectivity. Obtainable.
• the reaction temperature is preferably 300°C or higher, more preferably 350°C or higher.
• the contact time is preferably 10 g ⁇ sec/cc or more, more preferably 20 g ⁇ sec/cc or more, and further preferably 40 g ⁇ sec/cc or more.
• the reaction temperature is preferably 300°C or higher, and the contact time is preferably 5 g ⁇ sec/cc or higher.
• the reaction temperature is preferably 300°C or higher, more preferably 350°C or higher, and further preferably 400°C or higher.
• the contact time is preferably 5 g ⁇ sec/cc to 55 g ⁇ sec/cc, more preferably 5 g ⁇ sec/cc to 50 g ⁇ sec/cc, and more preferably 5 g ⁇ sec/cc to 40 g ⁇ sec/ More preferably cc.
• the reaction pressure of the desorption reaction is preferably -0.05MPa to 2MPa, more preferably -0.01MPa to 1MPa, from the viewpoint of promoting the desorption reaction more efficiently, and at atmospheric pressure. More preferably, the pressure is up to 0.5 MPa. Note that in the present disclosure, the pressure is a gauge pressure unless otherwise noted.
• the reactor for contacting the raw material compound and the catalyst (metal catalyst etc.) to react with each other is not particularly limited in shape and structure as long as it can withstand the above temperature and pressure.
• the reactor include a vertical reactor, a horizontal reactor, a multitubular reactor and the like.
• the material of the reactor include glass, stainless steel, iron, nickel, iron-nickel alloy and the like.
• the desorption reaction can be carried out by any of a flow system and a batch system in which a starting compound is continuously charged into a reactor and the target compound is continuously withdrawn from the reactor. If the target compound remains in the reactor, the elimination reaction can proceed further, so that it is preferably carried out in a flow system.
• the step of the desorption reaction in the present disclosure is preferably carried out in a gas phase, particularly preferably in a gas phase continuous flow system using a fixed bed reactor. When the gas phase continuous flow system is used, the apparatus, operation, etc. can be simplified, and it is economically advantageous.
• the atmosphere during the desorption reaction is preferably in the presence of an inert gas and/or hydrogen fluoride from the viewpoint of suppressing the deterioration of the catalyst (metal catalyst etc.).
• the inert gas is preferably at least one selected from the group consisting of nitrogen, helium, argon and carbon dioxide. Among these inert gases, nitrogen is more preferable from the viewpoint of cost reduction.
• the concentration of the inert gas is preferably 0 to 50 mol% of the gas component introduced into the reactor.
• a cyclobutene containing a halogen atom represented by the general formula (1) can be obtained by performing a purification treatment according to a conventional method as needed.
• Target compound The target compound in the present disclosure has the general formula (1):
• X 1 , X 2 , X 3 and X 4 are the same or different and each represents a hydrogen atom, a halogen atom or a perfluoroalkyl group.
• Y represents a halogen atom.
• It is a cyclobutene containing a halogen atom represented by.
• X 1 , X 2 , X 3 and X 4 , and Y are the same as defined above.
• Cyclobutene represented by the general formula (1) to be produced is, for example,
• X 1 , X 2 , X 3 and X 4 are the same or different and each represents a hydrogen atom, a halogen atom, or a perfluoroalkyl group, and Y is It is preferably a fluorine atom.
• X 1 , X 2 , X 3 and X 4 are more preferably a fluorine atom, and Y is more preferably a fluorine atom.
• the starting compound is a cyclobutane containing a halogen atom represented by the general formula (2), X 1 , X 2 , X 3 , X 4 and X 6 are fluorine. Atoms, X 5 is a hydrogen atom, and Y is a fluorine atom, which is preferably an elimination reaction.
• the elimination reaction is preferably a dehydrofluorination reaction.
• X 1 , X 2 , X 3 and X 4 are fluorine atoms, and Y is a fluorine atom.
• a composition containing a cyclobutene containing a halogen atom As described above, a cyclobutene containing a halogen atom represented by the general formula (1) can be obtained. It may be obtained in the form of a composition containing a cyclobutene containing a halogen atom represented by the formula and a cyclobutane containing a halogen atom represented by the general formula (2).
• X 1 , X 2 , X 3 and X 4 are fluorine atoms and Y is a fluorine atom.
• the content of the cyclobutene containing a halogen atom represented by the general formula (1) with the total amount of the composition being 100 mol %. Is preferably 95 mol% or more, and more preferably 99 mol% or more.
• the content of the cyclobutene containing a halogen atom represented by the general formula (1) with the total amount of the composition being 100 mol %. Is preferably 1 mol% to 99.9 mol%, more preferably 5 mol% to 99.9 mol%, still more preferably 10 mol% to 99.9 mol%.
• the following compounds may be produced as impurities in the above elimination reaction.
• the content of 1H-perfluorocyclobutene (1H-cC 4 F 5 H) is defined as 100 mol% of the total amount of the composition.
• the amount is 99 mol% or more, and the content of 3H-perfluorocyclobutene (3H-cC 4 F 5 H) is preferably 1 mol% or less.
• the halogen atom represented by the general formula (1) is contained.
• Cyclobutene can be obtained with a particularly high selectivity, and as a result, it is possible to reduce the components other than cyclobutene containing the halogen atom represented by the general formula (1) in the composition.
• labor for purification for obtaining a cyclobutene containing a halogen atom represented by the general formula (1) can be reduced.
• a composition containing a cyclobutene containing a halogen atom represented by the general formula (1) of the present disclosure has the same composition as a semiconductor, a liquid crystal, etc., as in the case of cyclobutene containing a halogen atom represented by the general formula (1) alone.
• the etching gas for forming the fine structure of the tip it can be effectively used for various purposes such as a deposit gas, a building block for organic synthesis, and a cleaning gas.
• the deposit gas is a gas that deposits the etching resistant polymer layer.
• the building block for organic synthesis means a substance that can be a precursor of a compound having a highly reactive skeleton.
• a fluorine-containing organosilicon compound such as CF 3 Si(CH 3 ) 3 , CF 3
• a fluoroalkyl group such as a group into a substance that can be a detergent or a fluorine-containing pharmaceutical intermediate.
• the starting compound is a cyclobutane containing a halogen atom represented by the general formula (2), X 1 , X 2 , X 3 , X 4 and X 6 are , A fluorine atom, X 5 was a hydrogen atom, and Y was a fluorine atom.
• the desorption reaction was dehydrofluorination reaction.
• the target compound is a cyclobutene containing a halogen atom represented by the general formula (1), wherein X 1 , X 2 , X 3 and X 4 are fluorine atoms, and Y is a fluorine atom.
• the following compounds may be produced as impurities in the above elimination reaction.
• Examples 1 to 3 (chromium oxide catalyst)
• a SUS pipe (outer diameter: 1/2 inch) was used as a reaction tube, and 10 g of chromium oxide containing Cr 2 O 3 as a main component was filled as a catalyst.
• anhydrous hydrogen fluoride was passed through the reactor, and the fluorination treatment was performed by setting the temperature of the reactor to 200°C to 300°C.
• the fluorinated chromium oxide was taken out and used for the dehydrofluorination reaction.
• the BET specific surface area of the fluorinated chromium oxide was 75 m 2 /g.
• the reaction proceeded in the gas phase continuous flow system.
• the reactor was heated at 250°C or 350°C to start the dehydrofluorination reaction.
• mass spectrometry is performed by gas chromatography/mass spectrometry (GC/MS) using gas chromatography (manufactured by Shimadzu Corporation, product name “GC-2014”), and NMR (manufactured by JEOL, product name “400YH”). ]) was used for structural analysis by NMR spectrum.
• GC/MS gas chromatography/mass spectrometry
• Example 1 the conversion rate from cC 4 F 6 H 2 (raw material compound) was 3.34 mol%, and the selectivity (yield) for cC 4 F 5 H (target compound) was 45.9 mol%.
• Example 2 the conversion was 29.1 mol% and the selectivity was 98.6 mol%.
• Example 3 the conversion was 26.1 mol% and the selectivity was 97.2 mol%.
• Examples 4 and 5 (alumina catalyst) Following the experimental method of Example 1, alumina containing Al 2 O 3 as a main component was used as a catalyst. Following the experimental method of Example 1, the contact time (W/F 0 ) between cC 4 F 6 H 2 (raw material compound) and alumina (catalyst) should be 10 g ⁇ sec/cc or 40 g ⁇ sec/cc. Then, the raw material compound was passed through the reactor. Following the experimental method of Example 1, the reactor was heated at 400° C. to start the dehydrofluorination reaction. Dehydrofluorination reaction, mass spectrometry and structural analysis were carried out in the same manner as in Example 1 except for the above conditions.
• Example 4 From the results of mass spectrometry and structural analysis, it was confirmed that cC 4 F 5 H was produced as the target compound.
• the conversion from cC 4 F 6 H 2 (raw material compound) was 7.92 mol%, and the selectivity of cC 4 F 5 H (target compound) was 45.1 mol%.
• the conversion rate was 4.11 mol% and the selectivity rate was 35.0 mol%.
• Examples 6 to 10 (activated carbon catalyst) Following the experimental method of Example 1, activated carbon was used as a catalyst. Following the experimental method of Example 1, the contact time (W/F 0 ) between cC 4 F 6 H 2 (raw material compound) and activated carbon (catalyst) was 10 g ⁇ sec/cc, 27 g ⁇ sec/cc or 47 g ⁇ sec. The raw material compound was passed through the reactor so as to be sec/cc. Following the experimental method of Example 1, the reactor was heated at 300° C., 350° C. or 400° C. to start the dehydrofluorination reaction. Dehydrofluorination reaction, mass spectrometry and structural analysis were carried out in the same manner as in Example 1 except for the above conditions.
• Example 6 the conversion from cC 4 F 6 H 2 (raw material compound) was 57.6 mol%, and the selectivity of cC 4 F 5 H (target compound) was 95.3 mol%.
• Example 7 the conversion was 97.7 mol% and the selectivity was 68.3 mol%.
• Example 8 the conversion was 84.1 mol% and the selectivity was 83.8 mol%.
• Example 9 the conversion rate was 72.3 mol% and the selectivity was 94.6 mol%.
• Example 10 the conversion was 84.7 mol% and the selectivity was 95.7 mol%.
• the contact time (W/F 0 ) means at what rate the flowing raw material gas is flown, that is, the time during which the catalyst and the raw material gas are in contact with each other.

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