CN112125551A - Pretreatment method for plant fibers in concrete - Google Patents
Pretreatment method for plant fibers in concrete Download PDFInfo
- Publication number
- CN112125551A CN112125551A CN202010994569.XA CN202010994569A CN112125551A CN 112125551 A CN112125551 A CN 112125551A CN 202010994569 A CN202010994569 A CN 202010994569A CN 112125551 A CN112125551 A CN 112125551A
- Authority
- CN
- China
- Prior art keywords
- fibers
- air
- nano
- solution
- silicon dioxide
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B20/00—Use of materials as fillers for mortars, concrete or artificial stone according to more than one of groups C04B14/00 - C04B18/00 and characterised by shape or grain distribution; Treatment of materials according to more than one of the groups C04B14/00 - C04B18/00 specially adapted to enhance their filling properties in mortars, concrete or artificial stone; Expanding or defibrillating materials
- C04B20/02—Treatment
- C04B20/023—Chemical treatment
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B18/00—Use of agglomerated or waste materials or refuse as fillers for mortars, concrete or artificial stone; Treatment of agglomerated or waste materials or refuse, specially adapted to enhance their filling properties in mortars, concrete or artificial stone
- C04B18/04—Waste materials; Refuse
- C04B18/18—Waste materials; Refuse organic
- C04B18/24—Vegetable refuse, e.g. rice husks, maize-ear refuse; Cellulosic materials, e.g. paper, cork
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/91—Use of waste materials as fillers for mortars or concrete
Abstract
A method for pretreating plant fibers in concrete comprises the steps of soaking the plant fibers in 2 wt.% of NaOH solution for 5-8 hours, taking out the plant fibers, washing the plant fibers clean, and naturally drying the plant fibers in the air, wherein the mass ratio of the plant fibers to the NaOH solution is 60-80%; filling 5 wt.% of nano-scale silicon dioxide SiO2 solution into a vacuum pressurizing box, putting the air-dried plant fibers obtained in the first step into the nano-scale silicon dioxide SiO2 solution, continuously soaking the plant fibers for 7-9 hours in a vacuum pressurizing state, and naturally air-drying the plant fibers for later use, wherein the mass ratio of the nano-scale silicon dioxide SiO2 solution to the air-dried plant fibers obtained in the first step is 50-70%; after the concrete is solidified and formed, the adhesive strength between the plant fiber and the concrete matrix is improved.
Description
Technical Field
The invention relates to the technical field of building materials, in particular to a pretreatment method for plant fibers in concrete.
Background
Research on plant fibers for concrete has been carried out for many years, wherein one of the problems to be solved in plant fiber concrete is the bonding strength between the plant fibers and the concrete matrix. Chinese patent application CN201911213349.2 discloses a plant fiber concrete, a preparation method and a plant fiber concrete column, wherein the plant fiber concrete with light weight, heat preservation and high strength is prepared by adding materials such as light aggregate consisting of vitrified micro-beads, waste polystyrene foam particles and hollow glass micro-beads, but the preparation method has low stability and does not have remarkable promotion effect, so that the problem of bonding strength between plant fibers and a concrete matrix cannot be solved. Chinese patent application CN201922122808.8 discloses a plant fiber concrete column, which can reduce the weight of the wall and achieve the effect of thermal insulation by adding plant fiber concrete on the basis of the original column, but because the patent application focuses on the thermal insulation function, the problem of the bonding strength between the plant fiber and the concrete matrix is not solved. In order to further put the plant fiber into practical engineering practice, a new plant fiber pretreatment method is urgently needed.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention aims to provide a method for pretreating plant fibers in concrete by adopting a sodium hydroxide NaOH solution and nano-scale silicon dioxide SiO2The solution is used for carrying out combined treatment on the plant fibers under the condition of vacuum pressurization, so that after the concrete is solidified and formed, the bonding strength between the plant fibers and the concrete matrix is improved.
In order to achieve the purpose, the invention adopts the technical scheme that:
a pretreatment method for plant fibers in concrete comprises the following steps:
the method comprises the following steps: soaking the plant fiber in 2 wt.% of sodium hydroxide NaOH solution for 5-8 hours, taking out, washing the plant fiber, and naturally drying in the air, wherein the mass ratio of the plant fiber to the sodium hydroxide NaOH solution is 60-80%;
step two: 5 wt.% of nano-scale silicon dioxide SiO2Pouring the solution into a vacuum pressure tank, and putting the air-dried plant fibers obtained in the step one into the nano-scale silicon dioxide SiO2In the solution, the plant fiber is continuously soaked for 7 to 9 hours under the vacuum pressurization state, and then the plant fiber is naturally dried for standby use, wherein the nano-scale silicon dioxide SiO2The mass ratio of the solution to the plant fiber air-dried in the first step is 50-70%.
The plant fiber is wood fiber or non-wood fiber.
The pressure of the vacuum pressure box is 50-60 MPA.
The invention adopts sodium hydroxide NaOH solution and nano-scale silicon dioxide SiO2The solution is used for carrying out combined treatment on the plant fibers under the condition of vacuum pressurization, so that after the concrete is solidified and formed, the bonding strength between the plant fibers and the concrete matrix is improved.
Drawings
FIG. 1 is a flow chart of the plant fiber pretreatment method of the present invention.
Detailed Description
The invention is described in detail below with reference to the figures and examples.
Referring to fig. 1, a method for pretreating plant fiber in concrete includes the following steps:
the method comprises the following steps: soaking the plant fiber in 2 wt.% of sodium hydroxide NaOH solution for 5-8 hours, taking out, washing the plant fiber, and naturally drying in the air, wherein the mass ratio of the plant fiber to the sodium hydroxide NaOH solution is 60-80%;
step two: pouring 5 wt.% of nano-scale silicon dioxide SiO2 solution into a vacuum pressure tank, and putting the air-dried plant fibers obtained in the first step into the nano-scale silicon dioxide SiO2And (2) continuously soaking the plant fibers in the solution for 7-9 hours under a vacuum pressurization state, and then naturally drying the plant fibers in the air for later use, wherein the mass ratio of the nano-scale silicon dioxide SiO2 solution to the plant fibers dried in the first step is 50-70%.
The plant fiber is wood fiber or non-wood fiber.
The pressure of the vacuum pressure box is 50-60 MPA.
The principle of the invention is as follows: 1. the components harmful to the bonding strength of the fiber and the concrete in the plant fiber can be removed by adopting a sodium hydroxide NaOH solution; 2. because the plant fiber has a cavity in the inner structure and holes on the surface, the nano-scale silicon dioxide SiO can be mixed2Filling the mixture therein; 3. the vacuum pressurization is more beneficial to the nano-scale silicon dioxide SiO2Into the plant fiber cavity structure.
Example 1
A pretreatment method for plant fibers in concrete comprises the following steps:
the method comprises the following steps: soaking the wheat straw fibers in 2 wt.% of sodium hydroxide NaOH solution for 6.5 hours, taking out the wheat straw fibers, washing the wheat straw fibers, and naturally airing the wheat straw fibers, wherein the mass ratio of the wheat straw fibers to the sodium hydroxide NaOH solution is 60%;
step two: filling 5 wt.% of nano-scale silicon dioxide SiO2 solution into a vacuum pressure chamber, and putting the air-dried wheat straw fiber obtained in the first step into the nano-scale silicon dioxide SiO2In the solution, the wheat straw fiber is continuously soaked for 8 hours under the vacuum pressure of 50MPA, and then is naturally dried for standby use, and the nano-scale silicon dioxide SiO2The mass ratio of the solution to the wheat straw fiber air-dried in the first step is 50%.
Example 2
A pretreatment method for plant fibers in concrete comprises the following steps:
the method comprises the following steps: soaking the bamboo fibers in 2 wt.% of sodium hydroxide NaOH solution for 6.5 hours, taking out the bamboo fibers, washing the bamboo fibers, and naturally drying the bamboo fibers in the air, wherein the mass ratio of the bamboo fibers to the sodium hydroxide NaOH solution is 65%;
step two: and (2) filling 5 wt.% of nano-scale silicon dioxide SiO2 solution into a vacuum pressurizing box, putting the bamboo plant fibers air-dried in the first step into the nano-scale silicon dioxide SiO2 solution, continuously soaking the bamboo fibers for 8 hours under the condition that the vacuum pressure is 50MPA, and naturally air-drying the bamboo fibers for later use, wherein the mass ratio of the nano-scale silicon dioxide SiO2 solution to the bamboo fibers air-dried in the first step is 55%.
Example 3
A pretreatment method for plant fibers in concrete comprises the following steps:
the method comprises the following steps: soaking the sisal fibers in 2 wt.% of NaOH solution for 6.5 hours, taking out the sisal fibers, washing the sisal fibers clean, and naturally drying the sisal fibers in air, wherein the mass ratio of the sisal fibers to the NaOH solution is 70%;
step two: and (2) filling 5 wt.% of nano-scale silicon dioxide SiO2 solution into a vacuum pressurizing box, putting the air-dried sisal fibers in the first step into the nano-scale silicon dioxide SiO2 solution, continuously soaking the sisal fibers for 8 hours under the condition that the vacuum pressure is 50MPA, and naturally drying the sisal fibers for later use, wherein the mass ratio of the nano-scale silicon dioxide SiO2 solution to the air-dried sisal fibers in the first step is 60%.
Example 4
A pretreatment method for plant fibers in concrete comprises the following steps:
the method comprises the following steps: soaking the masson pine needle fibers in a 2 wt.% sodium hydroxide NaOH solution for 6.5 hours, taking out the masson pine needle fibers, washing the masson pine needle fibers, and naturally drying the masson pine needle fibers in an air manner, wherein the mass ratio of the masson pine needle fibers to the sodium hydroxide NaOH solution is 75%;
step two: and (2) filling 5 wt.% of nano-scale silicon dioxide SiO2 solution into a vacuum pressurizing box, putting the air-dried masson pine needle fibers in the first step into the nano-scale silicon dioxide SiO2 solution, continuously soaking the masson pine needle fibers for 8 hours under the vacuum pressure of 50MPA, and naturally air-drying the masson pine needle fibers for later use, wherein the mass ratio of the nano-scale silicon dioxide SiO2 solution to the air-dried masson pine needle fibers in the first step is 65%.
Example 5
A pretreatment method for plant fibers in concrete comprises the following steps:
the method comprises the following steps: soaking the cork fibers in 2 wt.% of NaOH solution for 6.5 hours, taking out the cork fibers, washing the cork fibers clean, and naturally drying the cork fibers in air, wherein the mass ratio of the cork fibers to the NaOH solution is 80%;
step two: and (3) filling 5 wt.% of nano-scale silicon dioxide SiO2 solution into a vacuum pressurization box, putting the air-dried softwood fibers obtained in the first step into the nano-scale silicon dioxide SiO2 solution, continuously soaking the softwood fibers for 8 hours under the vacuum pressure of 50MPA, and naturally air-drying the softwood fibers for later use, wherein the mass ratio of the nano-scale silicon dioxide SiO2 solution to the air-dried softwood fibers obtained in the first step is 70%.
Claims (8)
1. A method for pretreating plant fibers in concrete is characterized by comprising the following steps:
the method comprises the following steps: soaking the plant fiber in 2 wt.% of sodium hydroxide NaOH solution for 5-8 hours, taking out, washing the plant fiber, and naturally drying in the air, wherein the mass ratio of the plant fiber to the sodium hydroxide NaOH solution is 60-80%;
step two: 5 wt.% of nano-scale silicon dioxide SiO2Pouring the solution into a vacuum pressure tank, and putting the air-dried plant fibers obtained in the step one into the nano-scale silicon dioxide SiO2In the solution, the plant fiber is continuously soaked for 7 to 9 hours under the vacuum pressurization state, and then the plant fiber is naturally dried for standby use, wherein the nano-scale silicon dioxide SiO2The mass ratio of the solution to the plant fiber air-dried in the first step is 50-70%.
2. The method as claimed in claim 1, wherein the plant fiber is wood fiber or non-wood fiber.
3. The method as claimed in claim 1, wherein the pressure of the vacuum pressure tank is 50-60 MPA.
4. The method for pretreating plant fibers in concrete according to claim 1, wherein the method comprises the following steps:
the method comprises the following steps: soaking the wheat straw fibers in 2 wt.% of sodium hydroxide NaOH solution for 6.5 hours, taking out the wheat straw fibers, washing the wheat straw fibers, and naturally airing the wheat straw fibers, wherein the mass ratio of the wheat straw fibers to the sodium hydroxide NaOH solution is 60%;
step two: filling 5 wt.% of nano-scale silicon dioxide SiO2 solution into a vacuum pressure chamber, and putting the air-dried wheat straw fiber obtained in the first step into the nano-scale silicon dioxide SiO2In the solution, the wheat straw fiber is subjected to vacuum pressure of 50MPAContinuously soaking for 8 hours in the state, and then naturally drying the nano-scale silicon dioxide SiO for later use2The mass ratio of the solution to the wheat straw fiber air-dried in the first step is 50%.
5. The method for pretreating plant fibers in concrete according to claim 1, wherein the method comprises the following steps:
the method comprises the following steps: soaking the bamboo fibers in 2 wt.% of sodium hydroxide NaOH solution for 6.5 hours, taking out the bamboo fibers, washing the bamboo fibers, and naturally drying the bamboo fibers in the air, wherein the mass ratio of the bamboo fibers to the sodium hydroxide NaOH solution is 65%;
step two: and (2) filling 5 wt.% of nano-scale silicon dioxide SiO2 solution into a vacuum pressurizing box, putting the bamboo plant fibers air-dried in the first step into the nano-scale silicon dioxide SiO2 solution, continuously soaking the bamboo fibers for 8 hours under the condition that the vacuum pressure is 50MPA, and naturally air-drying the bamboo fibers for later use, wherein the mass ratio of the nano-scale silicon dioxide SiO2 solution to the bamboo fibers air-dried in the first step is 55%.
6. The method for pretreating plant fibers in concrete according to claim 1, wherein the method comprises the following steps:
the method comprises the following steps: soaking the sisal fibers in 2 wt.% of NaOH solution for 6.5 hours, taking out the sisal fibers, washing the sisal fibers clean, and naturally drying the sisal fibers in air, wherein the mass ratio of the sisal fibers to the NaOH solution is 70%;
step two: and (2) filling 5 wt.% of nano-scale silicon dioxide SiO2 solution into a vacuum pressurizing box, putting the air-dried sisal fibers in the first step into the nano-scale silicon dioxide SiO2 solution, continuously soaking the sisal fibers for 8 hours under the condition that the vacuum pressure is 50MPA, and naturally drying the sisal fibers for later use, wherein the mass ratio of the nano-scale silicon dioxide SiO2 solution to the air-dried sisal fibers in the first step is 60%.
7. The method for pretreating plant fibers in concrete according to claim 1, wherein the method comprises the following steps:
the method comprises the following steps: soaking the masson pine needle fibers in a 2 wt.% sodium hydroxide NaOH solution for 6.5 hours, taking out the masson pine needle fibers, washing the masson pine needle fibers, and naturally drying the masson pine needle fibers in an air manner, wherein the mass ratio of the masson pine needle fibers to the sodium hydroxide NaOH solution is 75%;
step two: and (2) filling 5 wt.% of nano-scale silicon dioxide SiO2 solution into a vacuum pressurizing box, putting the air-dried masson pine needle fibers in the first step into the nano-scale silicon dioxide SiO2 solution, continuously soaking the masson pine needle fibers for 8 hours under the vacuum pressure of 50MPA, and naturally air-drying the masson pine needle fibers for later use, wherein the mass ratio of the nano-scale silicon dioxide SiO2 solution to the air-dried masson pine needle fibers in the first step is 65%.
8. The method for pretreating plant fibers in concrete according to claim 1, wherein the method comprises the following steps:
the method comprises the following steps: soaking the cork fibers in 2 wt.% of NaOH solution for 6.5 hours, taking out the cork fibers, washing the cork fibers clean, and naturally drying the cork fibers in air, wherein the mass ratio of the cork fibers to the NaOH solution is 80%;
step two: and (3) filling 5 wt.% of nano-scale silicon dioxide SiO2 solution into a vacuum pressurization box, putting the air-dried softwood fibers obtained in the first step into the nano-scale silicon dioxide SiO2 solution, continuously soaking the softwood fibers for 8 hours under the vacuum pressure of 50MPA, and naturally air-drying the softwood fibers for later use, wherein the mass ratio of the nano-scale silicon dioxide SiO2 solution to the air-dried softwood fibers obtained in the first step is 70%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010994569.XA CN112125551A (en) | 2020-09-21 | 2020-09-21 | Pretreatment method for plant fibers in concrete |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010994569.XA CN112125551A (en) | 2020-09-21 | 2020-09-21 | Pretreatment method for plant fibers in concrete |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112125551A true CN112125551A (en) | 2020-12-25 |
Family
ID=73843044
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010994569.XA Pending CN112125551A (en) | 2020-09-21 | 2020-09-21 | Pretreatment method for plant fibers in concrete |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112125551A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2758823C1 (en) * | 2021-04-09 | 2021-11-02 | Федеральное государственное бюджетное образовательное учреждение высшего образования "Национальный исследовательский Московский государственный строительный университет" (НИУ МГСУ) | Method for modifying cellulose-containing lightweight concrete aggregate |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5494748A (en) * | 1989-04-17 | 1996-02-27 | Ecco Gleittechnik Gmbh | Reinforcement fibers and/or process fibers based on plant fibers |
| CN105502987A (en) * | 2015-12-24 | 2016-04-20 | 哈尔滨工业大学 | Plant fiber processing method |
| CN105671937A (en) * | 2016-01-23 | 2016-06-15 | 武汉理工大学 | Modification method of ramie fibers using as environment-friendly composite material reinforcement |
| CN108341605A (en) * | 2018-02-26 | 2018-07-31 | 成都新柯力化工科技有限公司 | A kind of toughening biology bagasse fibre and preparation method for building concrete |
| CN108929074A (en) * | 2018-08-07 | 2018-12-04 | 长沙开润新材料科技有限公司 | A kind of silicon dioxide aerogel heat-insulating composite material plate and preparation method thereof |
-
2020
- 2020-09-21 CN CN202010994569.XA patent/CN112125551A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5494748A (en) * | 1989-04-17 | 1996-02-27 | Ecco Gleittechnik Gmbh | Reinforcement fibers and/or process fibers based on plant fibers |
| CN105502987A (en) * | 2015-12-24 | 2016-04-20 | 哈尔滨工业大学 | Plant fiber processing method |
| CN105671937A (en) * | 2016-01-23 | 2016-06-15 | 武汉理工大学 | Modification method of ramie fibers using as environment-friendly composite material reinforcement |
| CN108341605A (en) * | 2018-02-26 | 2018-07-31 | 成都新柯力化工科技有限公司 | A kind of toughening biology bagasse fibre and preparation method for building concrete |
| CN108929074A (en) * | 2018-08-07 | 2018-12-04 | 长沙开润新材料科技有限公司 | A kind of silicon dioxide aerogel heat-insulating composite material plate and preparation method thereof |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2758823C1 (en) * | 2021-04-09 | 2021-11-02 | Федеральное государственное бюджетное образовательное учреждение высшего образования "Национальный исследовательский Московский государственный строительный университет" (НИУ МГСУ) | Method for modifying cellulose-containing lightweight concrete aggregate |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109456003B (en) | Anti-permeability recycled concrete and preparation method thereof | |
| JP5775825B2 (en) | Surface-reinforced natural wood mold material and method for producing the same | |
| CN105418052B (en) | A kind of preparation process of carbon nano-fiber combined oxidation silica aerogel | |
| CN108117370B (en) | Normal-pressure preparation method of silicon dioxide aerogel thermal insulation board | |
| CN112125551A (en) | Pretreatment method for plant fibers in concrete | |
| CN109049215A (en) | A kind of preparation method of the flexible Wood composite material of transparent and electrically conductive | |
| CN111002413B (en) | Modified wood and preparation method and application thereof | |
| CN108585922A (en) | A kind of aeroge ceramic fibre heat-insulating shield and preparation method thereof | |
| CN104098922A (en) | Micronized plant fiber buffer material and preparation method thereof | |
| CN108527572B (en) | Transparent wood with optical regulation and control function and preparation method thereof | |
| CN107043224A (en) | A kind of foam glass SiO2The preparation method of aeroge | |
| CN105382895A (en) | Preparing method of modified composite wood for furniture manufacturing | |
| CN104526803A (en) | Surface-impregnated wood and preparing method thereof | |
| KR101042298B1 (en) | Artificial lumber using bamboo tree and method for manufacturing thereof | |
| CN108530927B (en) | Preparation method of wood fiber transparent high-strength composite material | |
| CN111302685A (en) | Preparation method of wheat straw fiber reinforced cement board and wheat straw fiber reinforced cement board | |
| CN109605516A (en) | A kind of manufacturing method of novel floor surface decoration material | |
| CN114407150A (en) | Energy-saving preparation method of environment-friendly functional wood | |
| CN107415002A (en) | A kind of weather-proof paulownia wood hardening process | |
| CN116160526B (en) | Porous bamboo material with high adsorptivity and composite material thereof, and preparation method and application thereof | |
| CN115319875B (en) | High-strength stable mildew-proof bamboo wood and preparation method thereof | |
| CN115230039A (en) | Bark-based rebound damping ground thermal insulation material | |
| LU500274B1 (en) | Method for preparing bamboo-based fiber composite for furniture from thin-walled bamboo | |
| CN110485193B (en) | Production process of pre-impregnated paper | |
| KR101261812B1 (en) | Laminate wood that is thermally modified and treated by nano material and manufacturing method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WD01 | Invention patent application deemed withdrawn after publication | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20201225 |