CN102773933A - Chemical processing method of wire-cutting recovery liquids - Google Patents
Chemical processing method of wire-cutting recovery liquids Download PDFInfo
- Publication number
- CN102773933A CN102773933A CN2011101236605A CN201110123660A CN102773933A CN 102773933 A CN102773933 A CN 102773933A CN 2011101236605 A CN2011101236605 A CN 2011101236605A CN 201110123660 A CN201110123660 A CN 201110123660A CN 102773933 A CN102773933 A CN 102773933A
- Authority
- CN
- China
- Prior art keywords
- liquid
- chemical treatment
- treatment method
- cutting
- polymer
- 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.)
- Granted
Links
Landscapes
- Compositions Of Macromolecular Compounds (AREA)
Abstract
The invention discloses a chemical processing method of wire-cutting recovery liquids. The method comprises adding carboxylic acid polymers and alcohol amine substances into a wire-cutting recovery liquid. The wire-cutting recovery liquids can be directly applied in silicon wafer cutting after treated by additives, and performances equivalent to novel cutting liquids can be obtained, so that the utilization ratio of the recovery liquids is improved and the production cost is reduced.
Description
Technical field
The invention belongs to the line cutting field of Silicon Wafer, be specifically related to the recovery liquid that from the mortar of Silicon Wafer line cutting, reclaims is carried out chemical treatment.
Background technology
Silicon chip is the basis of making solar cell, in the silicon chip cutting process, metal wire is wrapped on the guide roller, and mortar is brought into cutting zone by metal wire, and the driving lead wheel does relative motion to silicon rod (ingot), cuts into certain thickness silicon chip to silicon rod (ingot).In this process, be brought into the amount of mortar and the cut quality that performance has determined silicon chip.Usually mortar mainly is made up of liquid cutting liquid (like polyethylene glycol) and solid-state silicon carbide micro-powder; Wherein the silicon carbide micro-powder of high rigidity is main cutting medium, and polyethylene glycol (PEG) is dispersed in silicon carbide micro-powder on the cutting surface of silico briquette as the carrier of carborundum; Reduced the accumulation of mechanical stress in the cutting process; And, play the effect of cooling because the higher thermal capacitance of polyethylene glycol can be taken away a large amount of frictional heat that produce in the cutting process; Simultaneously the good flowability of polyethylene glycol can in time be taken away the accessory substance that produces in the cutting process, like silica flour and metal impurities, avoids at silicon chip surface influencing the yields of silicon chip because the gathering of large granular impurity causes the silicon chip surface out-of-flatness.
Mortar shared cost proportion in wire cutting technology is bigger, in cutting process, needs constantly to replenish new mortar, discharges waste mortar, and the main component of waste mortar is polyethylene glycol, silicon carbide micro-powder, silica flour and a spot of metal fillings impurity.For these used waste mortars, silicon chip processing enterprise generally carries out recycling to it and reduces cost, and reduces the pollution to environment.But reclaim the polyethylene glycol that obtains at present; Wherein still contain a spot of silica flour and metal fillings impurity, and the existence of silica flour and metal fillings impurity makes that wire cutting technology becomes unstable when reusing, the silicon chip surface quality descends; Therefore; The polyethylene glycol that recovery obtains generally needs could use again with after new polyethylene glycol mixes by proper proportion, and is disclosed like CN101623898A; Even directly use, but the moisture that reclaims in the liquid is had requirement, and the water content that reclaims liquid receives multiple factor affecting, restive and be extended to production.
Summary of the invention
Reclaim the problems referred to above of liquid in view of existing silicon chip line cutting; The present invention provides a kind of line cutting to reclaim the chemical treatment method of liquid; After the inventive method was handled, the line cutting was reclaimed liquid and need not to mix with new cutting liquid again, can directly use fully; And can obtain to cut the performance that liquid phase is worked as, thereby raising is reclaimed the utilization rate of liquid and is reduced production costs with new.
The purpose of this invention is to provide a kind of line cutting and reclaim the chemical treatment method of liquid, said method comprises the step that adds carboxylic acids polymer and alcamines material in the online cutting recovery liquid.
Term of the present invention " liquid is reclaimed in the line cutting " refers to and uses centrifugal separation technology that the waste mortar that produces in the line cutting process is reclaimed; The liquid that recovery obtains partly reclaims liquid for the line cutting; Its composition overwhelming majority is polyethylene glycol, propane diols or isopropanol recovering liquid, still contains the extremely silica flour and the metal fillings impurity of trace.Inorganic acids such as the liquid part of this recovery can use technology general in this area to handle again, for example, adds hydrofluoric acid and combines with silica flour, adds hydrochloric acid, nitric acid and metal reaction generate methods such as water soluble salt, reclaim the purity of liquid with further raising.
According to the present invention one preferred embodiment, said method can also comprise the step of pure ethers of further adding and/or phenylethylene polymer.
Term used in the present invention " polymer " is meant that by many identical simple construction unit is the raw material of synthetic polymer through the compound that covalent bond repeats to be formed by connecting.
According to the present invention one preferred embodiment, liquid is reclaimed in the cutting of said line can be selected from polyethylene glycol, propane diols or isopropanol recovering liquid.Wherein the molecular weight of polyethylene glycol is generally less than 300.
The carboxylic acids polymer is used to regulate viscosity and the pH value that liquid is reclaimed in the line cutting.One preferred embodiment according to the present invention; Described carboxylic acids polymer is an acrylic copolymer; Can be selected from maleic acid acrylic copolymer, acrylic acid-hydroxypropyl acrylate copolymer, acrylic acid-2-acrylamide-2-methyl propane sulfonic acid copolymer and the acrylic acid-acrylic acid ester-phosphonic acids-sulfonate quadripolymer any one; The molecular weight of this acrylic copolymer should be less than 5000; The addition of carboxylic acids polymer can reclaim 0.1～2%, preferred 0.1～1% of liquid gross weight for the line cutting.
Reclaim the decentralization in the liquid for strengthening the online cutting of silicon carbide powder; Can add for example alcamines dispersant of dispersant; The alcamines material can reclaim for example polyethylene glycol generation esterification of liquid with the line cutting; Generate big molecule, produce space steric effect, strengthen the online cutting of silicon carbide powder material and reclaim the dispersiveness in the liquid.According to the present invention one preferred embodiment, described alcamines material can be selected from any one in monoethanolamine, triethanolamine or the triethanolamine oleate.The addition of alcamines material can reclaim 0.1～2%, preferred 0.1～1% of liquid gross weight for the line cutting.
Additive of the present invention can also contain surface active agent alcohol ether class surfactant, and such surfactant can strengthen silicon carbide powder and the silica flour dispersiveness in cutting liquid in the wafer cutting process, prevent particle agglomeration.According to the present invention one preferred embodiment, described pure ethers can be selected from and be NPE, AEO or sodium sulfate of polyethenoxy ether of fatty alcohol.The addition of alcohol ethers can reclaim 0～2%, preferred 0.1～1% of liquid gross weight for the line cutting.
One preferred embodiment according to the present invention; In order further to optimize the dispersiveness and the suspension stability of cutting liquid; Also can add the phenylethylene polymer; The molecular weight of described phenylethylene polymer can be 2000-4000, and the addition of phenylethylene polymer can reclaim 0～2% of liquid gross weight for the line cutting, and preferable range is 0.1-1%.
According to the present invention one preferred embodiment, the total addition level of said carboxylic acids polymer, alcamines material and/or pure ethers and/or phenylethylene polymer can be that the line cutting reclaims the 0.5-8% of liquid gross weight, preferred 1-5%.Various additives should add according to permanent order, to avoid irreversible particle coagulation, influence its dispersiveness and stable.
One preferred embodiment according to the present invention; Under agitation said reagent being joined the line cutting reclaims in the liquid; The time interval that adds carboxylic acids polymer, alcamines material and/or pure ethers and/or phenylethylene polymer is 0.5-3 hour, preferred 1-3 hour.
The concrete steps that additive adds lambda line cutting recovery liquid are: at ambient temperature; At first slowly add the carboxylic acids polymer, in adition process, need to stir apparatus and do not stop to stir, still need stir 0.5-3 after the adding after individual hour; Add the alcamines dispersant again, continued then to stir 0.5-3 hour.
Liquid is reclaimed in the line cutting that has more than added carboxylic acids polymer and alcamines additive; Also can select to continue to add in alcohol ether surfactants, the phenylethylene polymer one or both; The mode such as the above-mentioned requirement that add; Slowly add, do not stop to stir, the joining day of every kind of reagent is spaced apart 0.5-3 hour.
Line cutting through mentioned reagent was handled is reclaimed liquid after recovery is used in cutting, can also handle again through above technical scheme, recycles once more.
The chemical treatment method that liquid is reclaimed in line cutting of the present invention can access the dispersiveness with the required excellence of cutting; Thermal conductivity and mobile cutting liquid; After this cutting liquid and silicon carbide micro-powder (this silicon carbide micro-powder can be the silicon carbide micro-powder of brand-new silicon carbide micro-powder, recovery or both mixtures) mix through means known in the art; Can directly apply to the silicon chip cutting technique; And obtain with new cutting liquid phase when in addition excellent more performance, thereby improve the utilization rate of recovery liquid and reduce production costs.
The specific embodiment
Embodiment 1
600 kilograms of (Liaoning Fine Chemical Industry Co., Ltd. of liquid are reclaimed in the cutting of taking polyethylene glycol line; Name of product KLsi-II, lot number 20110321F41), slowly add 12 kilograms of maleic acid acrylic copolymers then; Do not stop to stir 1 hour; Slowly add 0.6 kilogram of monoethanolamine again, continue to stir after 1 hour, obtain treated line cutting and reclaim liquid.
Liquid and silicon carbide micro-powder (trade name: silicon carbide micro-powder, good bright solar energy new material Co., Ltd in raising, lot number: SD110420-33) mix, after mixing, can directly apply in the line cutting production is reclaimed in the cutting of above-mentioned line.
Embodiment 2
600 kilograms of (Liaoning Fine Chemical Industry Co., Ltd. of liquid are reclaimed in the cutting of taking polyethylene glycol line; Name of product KLsi-II, lot number 20110321F41), slowly add 0.6 kilogram in acrylic acid-hydroxypropyl acrylate copolymer then; Do not stop to stir 3 hours; Slowly add 12 kilograms of monoethanolamines again, continue to stir after 3 hours, obtain treated line cutting and reclaim liquid.
Above-mentioned line cutting is reclaimed liquid and is mixed with silicon carbide micro-powder, after mixing, can directly apply in the line cutting production.
Embodiment 3
600 kilograms of liquid (Liaoning Fine Chemical Industry Co., Ltd., name of product KLsi-II, lot number 20110321F41) are reclaimed in the cutting of taking polyethylene glycol line; Slowly add 6 kilograms of acrylic acid-2-acrylamides-2-methyl propane sulfonic acid copolymer then, do not stop to stir 2 hours, slowly add 6 kilograms of triethanolamines again; Stir after 2 hours; Slowly add 0.6 kilogram of NPE again, continue to stir after 2 hours, obtain treated line cutting and reclaim liquid.
Above-mentioned line cutting is reclaimed liquid and is mixed with silicon carbide micro-powder, after mixing, can directly apply in the line cutting production.
Embodiment 4
600 kilograms of liquid (Liaoning Fine Chemical Industry Co., Ltd., name of product KLsi-II, lot number 20110321F41) are reclaimed in the cutting of taking polyethylene glycol line; Slowly add 0.6 kilogram of maleic acid acrylic copolymer then, do not stop to stir 2 hours, slowly add 6 kilograms of triethanolamine oleates again; Stir after 2 hours; Slowly add 6 kilograms of AEOs again, stir after 2 hours, slowly add 0.6 kilogram of phenylethylene polymer again; Continue to stir after 2 hours, obtain treated line cutting and reclaim liquid.
After above-mentioned line cutting is reclaimed liquid and mixed, can directly apply in the line cutting production.
Embodiment 5
600 kilograms of liquid (Liaoning Fine Chemical Industry Co., Ltd., name of product KLsi-II, lot number 20110321F41) are reclaimed in the cutting of taking polyethylene glycol line; Slowly add 6 kilograms of acrylic acid-acrylic acid ester-phosphonic acids-sulfonate quadripolymer then, do not stop to stir 2 hours, slowly add 0.6 kilogram of triethanolamine oleate again; Stir after 2 hours; Slowly add 0.6 kilogram of sodium sulfate of polyethenoxy ether of fatty alcohol (AES) again, stir after 2 hours, slowly add 6 kilograms of phenylethylene polymers again; Continue to stir after 2 hours, obtain treated line cutting and reclaim liquid.
After above-mentioned line cutting is reclaimed liquid and mixed, can directly apply in the line cutting production.
Embodiment 6
Get the cutting of propane diols line and reclaim liquid (Cologne, Liaoning Fine Chemical Co., Ltd) 600 kilograms, slowly add 3 kilograms of maleic acid acrylic copolymers then, do not stop to stir 2 hours; Slowly add 3 kilograms of triethanolamine oleates again, stir after 2 hours, slowly add 3 kilograms of sodium sulfate of polyethenoxy ether of fatty alcohol (AES) again; Stir after 2 hours; Slowly add 3 kilograms of phenylethylene polymers again, continue to stir after 2 hours, obtain treated line cutting and reclaim liquid.
After above-mentioned line cutting is reclaimed liquid and mixed, can directly apply in the line cutting production.
Embodiment 7
Get the cutting of isopropyl alcohol line and reclaim liquid (Cologne, Liaoning Fine Chemical Co., Ltd) 600 kilograms, slowly add 3 kilograms of maleic acid acrylic copolymers then, do not stop to stir 3 hours; Slowly add 3 kilograms of triethanolamine oleates again, stir after 2 hours, slowly add 3 kilograms of sodium sulfate of polyethenoxy ether of fatty alcohol (AES) again; Stir after 2 hours; Slowly add 3 kilograms of phenylethylene polymers again, continue to stir after 2 hours, obtain treated line cutting and reclaim liquid.
After above-mentioned line cutting is reclaimed liquid and mixed, can directly apply in the line cutting production.
Experimental example 1:
The 100% recovery polyethylene glycol of following table for handling through embodiment of the invention 1-7; With undressed 100% reclaim polyethylene glycol and 100% brand-new polyethylene glycol; After the silicon carbide micro-powder of same type mixed at equal pace, the effect under same line cutting technique parameter condition relatively.What wherein the cutter numerical table was levied is the cutting number of times of each batch metal wire before broken string; What average silicon wafer thickness deviation TTV characterized is the flatness of cutting back silicon chip surface; What the cutting qualification rate characterized is that the silicon chip that cutting obtains satisfies qualified ratio; These parameters all with the quality of mortar: dispersiveness, mobile and cooling property, relevant.
Adopt the cutting of the handled line of technical scheme of the present invention to reclaim liquid, the effect that cutting obtains obviously is superior to undressed recovery liquid, with the result of brand-new cutting liquid much at one.
Claims (13)
1. the chemical treatment method of liquid is reclaimed in line cutting, and said method comprises that online cutting reclaims the step that adds carboxylic acids polymer and alcamines material in the liquid.
2. chemical treatment method as claimed in claim 1 is characterized in that: the addition of said carboxylic acids polymer and alcamines material is the 0.1-2% that the liquid gross weight is reclaimed in the line cutting, preferred 0.1-1%.
3. chemical treatment method as claimed in claim 1 is characterized in that: said method also comprises the step that adds pure ethers and/or phenylethylene polymer.
4. chemical treatment method as claimed in claim 3 is characterized in that: the addition of said pure ethers and/or phenylethylene polymer is the 0-2% that the liquid gross weight is reclaimed in the line cutting, preferred 0.1-1%.
5. like the arbitrary described chemical treatment method of claim 1 to 4, it is characterized in that: said line cutting is reclaimed liquid and is selected from polyethylene glycol, propane diols or isopropanol recovering liquid.
6. like the arbitrary described chemical treatment method of claim 1 to 5; It is characterized in that: described carboxylic acids polymer is an acrylic copolymer, is selected from maleic acid acrylic copolymer, acrylic acid-hydroxypropyl acrylate copolymer, acrylic acid-2-acrylamide-2-methyl propane sulfonic acid copolymer and the acrylic acid-acrylic acid ester-phosphonic acids-sulfonate quadripolymer any one.
7. chemical treatment method as claimed in claim 6 is characterized in that: the molecular weight of said acrylic copolymer is less than 5000.
8. like the arbitrary described chemical treatment method of claim 1 to 7, it is characterized in that: described alcamines material is selected from any one in monoethanolamine, triethanolamine or the triethanolamine oleate.
9. chemical treatment method as claimed in claim 3 is characterized in that: described pure ethers is selected from NPE, AEO or sodium sulfate of polyethenoxy ether of fatty alcohol.
10. chemical treatment method as claimed in claim 3 is characterized in that: the molecular weight of described phenylethylene polymer is 2000～4000.
11. like the arbitrary described chemical treatment method of claim 1 to 10; It is characterized in that: the total addition level of said carboxylic acids polymer, alcamines material and/or pure ethers and/or phenylethylene polymer is the 0.5-8% that the liquid gross weight is reclaimed in the line cutting, preferred 1-5%.
12. like the arbitrary described chemical treatment method of claim 1 to 11; It is characterized in that: under agitation carboxylic acids polymer, alcamines material, optional pure ethers and/or phenylethylene polymer are joined in the line cutting recovery liquid; The time interval that adds all ingredients is 0.5-3 hour, preferred 1-3 hour.
13. like the arbitrary described chemical treatment method of claim 1 to 12, it is characterized in that: the carboxylic acids polymer added before the alcamines material.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110123660.5A CN102773933B (en) | 2011-05-13 | 2011-05-13 | Chemical processing method of wire-cutting recovery liquids |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110123660.5A CN102773933B (en) | 2011-05-13 | 2011-05-13 | Chemical processing method of wire-cutting recovery liquids |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102773933A true CN102773933A (en) | 2012-11-14 |
| CN102773933B CN102773933B (en) | 2014-11-05 |
Family
ID=47119148
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201110123660.5A Active CN102773933B (en) | 2011-05-13 | 2011-05-13 | Chemical processing method of wire-cutting recovery liquids |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102773933B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105462677A (en) * | 2014-09-10 | 2016-04-06 | 新郑市宝德高技术有限公司 | Cutting fluid recovery method |
| CN107098346A (en) * | 2017-06-18 | 2017-08-29 | 郑州东林润光伏材料科技有限公司 | A kind of recovery method of silicon carbide micro-powder |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003041240A (en) * | 2001-05-23 | 2003-02-13 | Fujimi Inc | Cutting grain, cutting composition containing the same, and method for producing silicon wafer using the composition |
| CN101016439A (en) * | 2007-02-06 | 2007-08-15 | 中国科学院上海微系统与信息技术研究所 | Chemical mechanical polishing pulp for sapphire substrate underlay |
| CN101113029A (en) * | 2006-07-26 | 2008-01-30 | 金柏林 | Treatment recovery method for monocrystalline silicon cutting waste liquor |
| CN101368126A (en) * | 2007-08-16 | 2009-02-18 | 江苏海迅实业集团股份有限公司 | Liquid coolant for cutting wire-electrode |
| CN101623898A (en) * | 2009-04-28 | 2010-01-13 | 江西赛维Ldk太阳能高科技有限公司 | Chemical recovery method for mortar in wire cutting technology |
| CN102027100A (en) * | 2008-04-28 | 2011-04-20 | Ppt研究公司 | A cutting and lubricating composition for use with a wire cutting apparatus |
| WO2011044718A1 (en) * | 2009-10-16 | 2011-04-21 | Dow Global Technologies Llc | Aqueous cutting fluid for use with diamond wiresaw |
-
2011
- 2011-05-13 CN CN201110123660.5A patent/CN102773933B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003041240A (en) * | 2001-05-23 | 2003-02-13 | Fujimi Inc | Cutting grain, cutting composition containing the same, and method for producing silicon wafer using the composition |
| CN101113029A (en) * | 2006-07-26 | 2008-01-30 | 金柏林 | Treatment recovery method for monocrystalline silicon cutting waste liquor |
| CN101016439A (en) * | 2007-02-06 | 2007-08-15 | 中国科学院上海微系统与信息技术研究所 | Chemical mechanical polishing pulp for sapphire substrate underlay |
| CN101368126A (en) * | 2007-08-16 | 2009-02-18 | 江苏海迅实业集团股份有限公司 | Liquid coolant for cutting wire-electrode |
| CN102027100A (en) * | 2008-04-28 | 2011-04-20 | Ppt研究公司 | A cutting and lubricating composition for use with a wire cutting apparatus |
| CN101623898A (en) * | 2009-04-28 | 2010-01-13 | 江西赛维Ldk太阳能高科技有限公司 | Chemical recovery method for mortar in wire cutting technology |
| WO2011044718A1 (en) * | 2009-10-16 | 2011-04-21 | Dow Global Technologies Llc | Aqueous cutting fluid for use with diamond wiresaw |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105462677A (en) * | 2014-09-10 | 2016-04-06 | 新郑市宝德高技术有限公司 | Cutting fluid recovery method |
| CN107098346A (en) * | 2017-06-18 | 2017-08-29 | 郑州东林润光伏材料科技有限公司 | A kind of recovery method of silicon carbide micro-powder |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102773933B (en) | 2014-11-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103588414B (en) | High-performance polycarboxylic acid water reducer and special compound admixture containing the water reducer for limestone powder concrete | |
| CN104302596B (en) | Process for manufacturing a hydraulic bonding agent, corresponding additive and its use | |
| CN104926190B (en) | A kind of composite cement grinding aid | |
| CN103553468B (en) | Gold mine tailings and fluorite mine tailing is utilized to make the method for aerated bricks | |
| CN102041138B (en) | Additive for improving utilization ratio of silicon crystal line cutting mortar as well as preparation method and application method of addictive | |
| CN106977129A (en) | Anti- mud collapse protective poly-carboxylic acid high efficiency water reducing agent and preparation method thereof | |
| CN103253886A (en) | Polycarboxylate superplasticizer synergist and preparation method thereof | |
| CN101935579B (en) | Water-base cutting liquid for hard and brittle materials and preparation method and application thereof | |
| CN102773933B (en) | Chemical processing method of wire-cutting recovery liquids | |
| CN108328959A (en) | A kind of three high mother liquor of polycarboxylic acids and its manufacturing method | |
| CN105273823A (en) | Multiline silicon wafer water soluble cutting liquid and preparation method thereof | |
| CN106045243A (en) | Metallurgical water station sludge modifier and preparation method | |
| CN105271880B (en) | Cement grinding aid | |
| CN106566646A (en) | Water based glass cutting fluid and preparation method thereof | |
| CN103639063B (en) | A kind of silicon carbide micro-powder reclaims medicament | |
| CN102229792B (en) | Solar silicon wafer cutting mortar | |
| CN101279860B (en) | Method for improving appearance quality of granules made from diammonium phosphate slurry | |
| CN110713685A (en) | Specific photovoltaic diamond wire-cutting acidic plastic plate and preparation method thereof | |
| CN102234379A (en) | Method for reducing use amount of new silicon carbide abrasive in solar silicon wafer cutting mortar | |
| CN102417664A (en) | Forming agent for hard alloy production | |
| CN103623935A (en) | High-purity silicon carbide recovery floatation agent and preparing method thereof | |
| CN102167968B (en) | Method for nuisanceless resourceful treatment of waste mortar from silicon chip cutting | |
| CN104004174B (en) | A kind of method preparing polycarboxylate water-reducer macromonomer using discarded lithium battery | |
| CN104909598B (en) | A kind of prodan cement grinding aid and preparation method thereof | |
| CN106396462B (en) | A kind of collapse protective poly-carboxylic acid water reducing agent and its preparation method and application |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |