CN105462367A - Flying-dust-free erasable chalk - Google Patents
Flying-dust-free erasable chalk Download PDFInfo
- Publication number
- CN105462367A CN105462367A CN201511011772.6A CN201511011772A CN105462367A CN 105462367 A CN105462367 A CN 105462367A CN 201511011772 A CN201511011772 A CN 201511011772A CN 105462367 A CN105462367 A CN 105462367A
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- CN
- China
- Prior art keywords
- parts
- chalk
- airborne dust
- modified landplaster
- linters
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Classifications
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D13/00—Pencil-leads; Crayon compositions; Chalk compositions
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Wood Science & Technology (AREA)
- Organic Chemistry (AREA)
- Inks, Pencil-Leads, Or Crayons (AREA)
Abstract
The invention discloses a flying-dust-free erasable chalk which is prepared from the following raw materials in parts by weight: 20-60 parts of modified gypsum powder, 20-40 parts of ceramic powder, 5-12 parts of titanium dioxide, 1-5 parts of linters, 2-5 parts of 2-ethyl hexyl ester of epoxidized soybean oil, 2-6 parts of paraffin, 0.5-1.5 parts of pigment and 150-220 parts of water. The preparation process comprises the following steps: uniformly stirring the modified gypsum powder, ceramic powder, titanium dioxide, linters and water according to the proportion, heating to 200-240 DEG C, stirring for 40-60 minutes, adding the 2-ethyl hexyl ester of epoxidized soybean oil, paraffin and pigment, uniformly stirring, injecting into a chalk mold, cooling and curing to obtain the flying-dust-free erasable chalk. The flying-dust-free erasable chalk has moderate hardness and certain roughness, is convenient for writing, can not generate flying dust when being matched with a magnetic blackboard, has an environment-friendly function, and is beneficial to improving the teaching environment.
Description
Technical field
The present invention relates to chalk technical field, particularly relate to a kind of without the easy erasing chalk of airborne dust.
Background technology
Chalk is generally be made up of plaster stone, can add various pigment and make pastel.In general making processes, by plaster stone is heated to certain temperature, makes its partial dehydration age gypsum, then the plaster of Paris is added water and stir into pasty state, pour into model and solidify and form.Teacher often need write on blackboard, draw when explaining, and often on hand, on sleeve, even hair, shoulder all leaves one deck chalk dust, inevitably also can suck some chalk dusts from nostril, cause the various respiratory tract disease of human body.
Summary of the invention
The present invention proposes one without the easy erasing chalk of airborne dust, hardness is moderate, has certain roughness, writes conveniently, with magnet board with the use of producing airborne dust, has environmental-protection function, contribute to improving teaching environment.
The one that the present invention proposes is without the easy erasing chalk of airborne dust, and its raw material comprises by weight: modified landplaster 20 ~ 60 parts, ceramics powder 20 ~ 40 parts, titanium dioxide 5 ~ 12 parts, linters 1 ~ 5 part, ethyl hexyl ester of epoxidized soybean oil 2 ~ 5 parts, 2 ~ 6 parts, paraffin, pigment 0.5 ~ 1.5 part, 150 ~ 220 parts, water; In preparation process, by proportioning, modified landplaster, ceramics powder, titanium dioxide, linters, water are stirred, be warming up to 200 ~ 240 DEG C and stir 40 ~ 60min, add ethyl hexyl ester of epoxidized soybean oil, paraffin, pigment stirs, inject chalk forming die tool, cooling, solidification, obtains without the easy erasing chalk of airborne dust.
Preferably, modified landplaster adopts following technique to prepare: by terra alba, plant ash, iron trichloride, ferrous sulfate, water mixing and stirring, continuing in whipping process, instill potassium hydroxide solution to system pH is 9 ~ 10.5, leave standstill, suction filtration, dry, add ethanolic soln to stir, continuing in whipping process, to add anhydrous acetic acid to system pH is 5.5 ~ 5.9, continue to add dimethyldimethoxysil,ne, zeolite, white carbon black stirs, filter, washing, be placed in ethanolic soln to soak, filter, washing, send in 100 ~ 150 DEG C of baking ovens and be incubated 5 ~ 10h, obtain modified landplaster.
Preferably, in the preparation technology of modified landplaster, the weight ratio of terra alba, plant ash, iron trichloride, ferrous sulfate is 20 ~ 50:20 ~ 30:1 ~ 5:2 ~ 6.
Preferably, in the preparation technology of modified landplaster, the weight ratio of dimethyldimethoxysil,ne, zeolite, white carbon black is 1 ~ 1.8:2 ~ 6:0.5 ~ 4.
Preferably, modified landplaster adopts following technique to prepare: by weight by 20 ~ 50 parts of terra albas, 20 ~ 30 parts of plant ash, 1 ~ 5 part of iron trichloride, 2 ~ 6 parts of ferrous sulfate, 100 ~ 150 parts of water mixing and stirring, continue in whipping process, instill concentration be potassium hydroxide solution to the system pH of 2 ~ 4.5mol/L is 9 ~ 10.5, leave standstill 2 ~ 8 days, suction filtration, dry, adding 50 ~ 80 parts of massfractions is that 50 ~ 60wt% ethanolic soln stirs 40 ~ 60min, continuing in whipping process, to add anhydrous acetic acid to system pH is 5.5 ~ 5.9, continue to add 1 ~ 1.8 part of dimethyldimethoxysil,ne, 2 ~ 6 parts of zeolites, 0.5 ~ 4 part of white carbon black stirs 5 ~ 30min, filter, washing, be placed in ethanolic soln immersion 40 ~ 60h that volume fraction is 50 ~ 65%, filter, washing, send in 100 ~ 150 DEG C of baking ovens and be incubated 5 ~ 10h, obtain modified landplaster.
Preferably, the weight ratio of modified landplaster, ceramics powder, titanium dioxide, linters is 40 ~ 55:30 ~ 36:8 ~ 10:2 ~ 3.5.
Preferably, the weight ratio of modified landplaster, ethyl hexyl ester of epoxidized soybean oil, paraffin is 40 ~ 55:3 ~ 4.2:3 ~ 5.
Preferably, described without the easy erasing chalk of airborne dust, its raw material comprises by weight: modified landplaster 40 ~ 55 parts, ceramics powder 30 ~ 36 parts, titanium dioxide 8 ~ 10 parts, linters 2 ~ 3.5 parts, ethyl hexyl ester of epoxidized soybean oil 3 ~ 4.2 parts, 3 ~ 5 parts, paraffin, pigment 1 ~ 1.2 part, 160 ~ 180 parts, water; In preparation process, by proportioning, modified landplaster, ceramics powder, titanium dioxide, linters, water are stirred, be warming up to 220 ~ 225 DEG C and stir 50 ~ 56min, add ethyl hexyl ester of epoxidized soybean oil, paraffin, pigment stirs, inject chalk forming die tool, cooling, solidification, obtains without the easy erasing chalk of airborne dust.
In the preparation technology of modified landplaster, in iron trichloride, ferrous sulfate ferrous ion and ferric ion can deposit in alkaline system, be adsorbed on terra alba and plant ash surface form one deck magnetic nano-particle, zeolite, white carbon black are grafted on terra alba surface under the effect of dimethyldimethoxysil,ne, ethanolic soln, make that gained modified landplaster not only has magnetic, surfaceness is high, and cost is low, adsorptive power is extremely strong; Modified landplaster is under the effect of ethyl hexyl ester of epoxidized soybean oil, paraffin, cooperatively interact with ceramics powder, titanium dioxide, linters, not only filling properties is fabulous, save cost, there is the writing effect of wax crayon, write facility, and the dust dropped can adsorb formation macrobead immediately mutually, dust macrobead is attracted on magnet board simultaneously, can not produce dust from flying, convenient erasing.
The present invention adopts modified landplaster, ceramics powder, titanium dioxide, linters to cooperatively interact, and gained is moderate without airborne dust easy erasing chalk chalk hardness, has certain roughness, write conveniently, with magnet board with the use of can not airborne dust be produced, there is environmental-protection function, contribute to improving teaching environment.
Embodiment
Embodiment 1
A kind of without the easy erasing chalk of airborne dust, its raw material comprises by weight: modified landplaster 20 parts, ceramics powder 40 parts, titanium dioxide 5 parts, linters 5 parts, ethyl hexyl ester of epoxidized soybean oil 2 parts, 6 parts, paraffin, pigment 0.5 part, 220 parts, water; In preparation process, by proportioning, modified landplaster, ceramics powder, titanium dioxide, linters, water are stirred, be warming up to 200 DEG C and stir 60min, add ethyl hexyl ester of epoxidized soybean oil, paraffin, pigment stirs, inject chalk forming die tool, cooling, solidification, obtains without the easy erasing chalk of airborne dust.
Embodiment 2
A kind of without the easy erasing chalk of airborne dust, its raw material comprises by weight: modified landplaster 60 parts, ceramics powder 20 parts, titanium dioxide 12 parts, linters 1 part, ethyl hexyl ester of epoxidized soybean oil 5 parts, 2 parts, paraffin, pigment 1.5 parts, 150 parts, water; In preparation process, by proportioning, modified landplaster, ceramics powder, titanium dioxide, linters, water are stirred, be warming up to 240 DEG C and stir 40min, add ethyl hexyl ester of epoxidized soybean oil, paraffin, pigment stirs, inject chalk forming die tool, cooling, solidification, obtains without the easy erasing chalk of airborne dust.
Embodiment 3
A kind of without the easy erasing chalk of airborne dust, its raw material comprises by weight: modified landplaster 40 parts, ceramics powder 36 parts, titanium dioxide 8 parts, linters 3.5 parts, ethyl hexyl ester of epoxidized soybean oil 3 parts, 5 parts, paraffin, pigment 1 part, 180 parts, water; In preparation process, by proportioning, modified landplaster, ceramics powder, titanium dioxide, linters, water are stirred, be warming up to 220 DEG C and stir 56min, add ethyl hexyl ester of epoxidized soybean oil, paraffin, pigment stirs, inject chalk forming die tool, cooling, solidification, obtains without the easy erasing chalk of airborne dust.
Modified landplaster adopts following technique to prepare: by weight by 20 parts of terra albas, 30 parts of plant ash, 1 part of iron trichloride, 6 parts of ferrous sulfate, 100 parts of water mixing and stirring, continue in whipping process, instill concentration be potassium hydroxide solution to the system pH of 4.5mol/L is 9, leave standstill 8 days, suction filtration, dry, adding 50 parts of massfractions is that 60wt% ethanolic soln stirs 40min, continuing in whipping process, to add anhydrous acetic acid to system pH is 5.9, continue to add 1 part of dimethyldimethoxysil,ne, 6 parts of zeolites, 0.5 part of white carbon black stirs 30min, filter, washing, be placed in volume fraction be 50% ethanolic soln soak 60h, filter, washing, send in 100 DEG C of baking ovens and be incubated 10h, obtain modified landplaster.
Embodiment 4
A kind of without the easy erasing chalk of airborne dust, its raw material comprises by weight: modified landplaster 55 parts, ceramics powder 30 parts, titanium dioxide 10 parts, linters 2 parts, ethyl hexyl ester of epoxidized soybean oil 4.2 parts, 3 parts, paraffin, pigment 1.2 parts, 160 parts, water; In preparation process, by proportioning, modified landplaster, ceramics powder, titanium dioxide, linters, water are stirred, be warming up to 225 DEG C and stir 50min, add ethyl hexyl ester of epoxidized soybean oil, paraffin, pigment stirs, inject chalk forming die tool, cooling, solidification, obtains without the easy erasing chalk of airborne dust.
Modified landplaster adopts following technique to prepare: by weight by 50 parts of terra albas, 20 parts of plant ash, 5 parts of iron trichlorides, 2 parts of ferrous sulfate, 150 parts of water mixing and stirring, continue in whipping process, instill concentration be potassium hydroxide solution to the system pH of 2mol/L is 10.5, leave standstill 2 days, suction filtration, dry, adding 80 parts of massfractions is that 50wt% ethanolic soln stirs 60min, continuing in whipping process, to add anhydrous acetic acid to system pH is 5.5, continue to add 1.8 parts of dimethyldimethoxysil,ne, 2 parts of zeolites, 4 parts of white carbon blacks stir 5min, filter, washing, be placed in volume fraction be 65% ethanolic soln soak 40h, filter, washing, send in 150 DEG C of baking ovens and be incubated 5h, obtain modified landplaster.
Embodiment 5
A kind of without the easy erasing chalk of airborne dust, its raw material comprises by weight: modified landplaster 48 parts, ceramics powder 33 parts, titanium dioxide 9 parts, linters 3 parts, ethyl hexyl ester of epoxidized soybean oil 3.5 parts, 4 parts, paraffin, pigment 1.1 parts, 170 parts, water; In preparation process, by proportioning, modified landplaster, ceramics powder, titanium dioxide, linters, water are stirred, be warming up to 223 DEG C and stir 53min, add ethyl hexyl ester of epoxidized soybean oil, paraffin, pigment stirs, inject chalk forming die tool, cooling, solidification, obtains without the easy erasing chalk of airborne dust.
Modified landplaster adopts following technique to prepare: by weight by 35 parts of terra albas, 25 parts of plant ash, 3 parts of iron trichlorides, 4 parts of ferrous sulfate, 125 parts of water mixing and stirring, continue in whipping process, instill concentration be potassium hydroxide solution to the system pH of 3mol/L is 10, leave standstill 5 days, suction filtration, dry, adding 65 parts of massfractions is that 55wt% ethanolic soln stirs 50min, continuing in whipping process, to add anhydrous acetic acid to system pH is 5.7, continue to add 1.4 parts of dimethyldimethoxysil,ne, 4 parts of zeolites, 2 parts of white carbon blacks stir 18min, filter, washing, be placed in volume fraction be 58% ethanolic soln soak 50h, filter, washing, send in 120 DEG C of baking ovens and be incubated 8h, obtain modified landplaster.
The above; be only the present invention's preferably embodiment; but protection scope of the present invention is not limited thereto; anyly be familiar with those skilled in the art in the technical scope that the present invention discloses; be equal to according to technical scheme of the present invention and inventive concept thereof and replace or change, all should be encompassed within protection scope of the present invention.
Claims (8)
1. one kind without the easy erasing chalk of airborne dust, it is characterized in that, its raw material comprises by weight: modified landplaster 20 ~ 60 parts, ceramics powder 20 ~ 40 parts, titanium dioxide 5 ~ 12 parts, linters 1 ~ 5 part, ethyl hexyl ester of epoxidized soybean oil 2 ~ 5 parts, 2 ~ 6 parts, paraffin, pigment 0.5 ~ 1.5 part, 150 ~ 220 parts, water; In preparation process, by proportioning, modified landplaster, ceramics powder, titanium dioxide, linters, water are stirred, be warming up to 200 ~ 240 DEG C and stir 40 ~ 60min, add ethyl hexyl ester of epoxidized soybean oil, paraffin, pigment stirs, inject chalk forming die tool, cooling, solidification, obtains without the easy erasing chalk of airborne dust.
2. according to claim 1 without the easy erasing chalk of airborne dust, it is characterized in that, modified landplaster adopts following technique to prepare: by terra alba, plant ash, iron trichloride, ferrous sulfate, water mixing and stirring, continuing in whipping process, instill potassium hydroxide solution to system pH is 9 ~ 10.5, leave standstill, suction filtration, dry, add ethanolic soln to stir, continuing in whipping process, to add anhydrous acetic acid to system pH is 5.5 ~ 5.9, continue to add dimethyldimethoxysil,ne, zeolite, white carbon black stirs, filter, washing, be placed in ethanolic soln to soak, filter, washing, send in 100 ~ 150 DEG C of baking ovens and be incubated 5 ~ 10h, obtain modified landplaster.
3. according to claim 2ly it is characterized in that without the easy erasing chalk of airborne dust, in the preparation technology of modified landplaster, the weight ratio of terra alba, plant ash, iron trichloride, ferrous sulfate is 20 ~ 50:20 ~ 30:1 ~ 5:2 ~ 6.
4. according to claim 2ly it is characterized in that without the easy erasing chalk of airborne dust, in the preparation technology of modified landplaster, the weight ratio of dimethyldimethoxysil,ne, zeolite, white carbon black is 1 ~ 1.8:2 ~ 6:0.5 ~ 4.
5. according to any one of claim 1-4 without the easy erasing chalk of airborne dust, it is characterized in that, modified landplaster adopts following technique to prepare: by weight by 20 ~ 50 parts of terra albas, 20 ~ 30 parts of plant ash, 1 ~ 5 part of iron trichloride, 2 ~ 6 parts of ferrous sulfate, 100 ~ 150 parts of water mixing and stirring, continue in whipping process, instill concentration be potassium hydroxide solution to the system pH of 2 ~ 4.5mol/L is 9 ~ 10.5, leave standstill 2 ~ 8 days, suction filtration, dry, adding 50 ~ 80 parts of massfractions is that 50 ~ 60wt% ethanolic soln stirs 40 ~ 60min, continuing in whipping process, to add anhydrous acetic acid to system pH is 5.5 ~ 5.9, continue to add 1 ~ 1.8 part of dimethyldimethoxysil,ne, 2 ~ 6 parts of zeolites, 0.5 ~ 4 part of white carbon black stirs 5 ~ 30min, filter, washing, be placed in ethanolic soln immersion 40 ~ 60h that volume fraction is 50 ~ 65%, filter, washing, send in 100 ~ 150 DEG C of baking ovens and be incubated 5 ~ 10h, obtain modified landplaster.
6. according to any one of claim 1-4 without the easy erasing chalk of airborne dust, it is characterized in that, the weight ratio of modified landplaster, ceramics powder, titanium dioxide, linters is 40 ~ 55:30 ~ 36:8 ~ 10:2 ~ 3.5.
7. according to any one of claim 1-4 without the easy erasing chalk of airborne dust, it is characterized in that, the weight ratio of modified landplaster, ethyl hexyl ester of epoxidized soybean oil, paraffin is 40 ~ 55:3 ~ 4.2:3 ~ 5.
8. according to any one of claim 1-7 without the easy erasing chalk of airborne dust, it is characterized in that, its raw material comprises by weight: modified landplaster 40 ~ 55 parts, ceramics powder 30 ~ 36 parts, titanium dioxide 8 ~ 10 parts, linters 2 ~ 3.5 parts, ethyl hexyl ester of epoxidized soybean oil 3 ~ 4.2 parts, 3 ~ 5 parts, paraffin, pigment 1 ~ 1.2 part, 160 ~ 180 parts, water; In preparation process, by proportioning, modified landplaster, ceramics powder, titanium dioxide, linters, water are stirred, be warming up to 220 ~ 225 DEG C and stir 50 ~ 56min, add ethyl hexyl ester of epoxidized soybean oil, paraffin, pigment stirs, inject chalk forming die tool, cooling, solidification, obtains without the easy erasing chalk of airborne dust.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201511011772.6A CN105462367A (en) | 2015-12-30 | 2015-12-30 | Flying-dust-free erasable chalk |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201511011772.6A CN105462367A (en) | 2015-12-30 | 2015-12-30 | Flying-dust-free erasable chalk |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN105462367A true CN105462367A (en) | 2016-04-06 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201511011772.6A Pending CN105462367A (en) | 2015-12-30 | 2015-12-30 | Flying-dust-free erasable chalk |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2019019722A1 (en) * | 2017-07-25 | 2019-01-31 | 中国科学院上海硅酸盐研究所 | Chalk for ceramic painting/marking and preparation method therefor |
| CN114031980A (en) * | 2021-12-23 | 2022-02-11 | 浙江理工大学 | Magnetic wax crayon capable of writing |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102911560A (en) * | 2012-11-12 | 2013-02-06 | 山西大学 | Dustless colored chalk dedicated for whiteboard capable of fading chemically |
| CN103468062A (en) * | 2013-08-30 | 2013-12-25 | 龙启知 | Neodymium iron boron magnetic chalk |
-
2015
- 2015-12-30 CN CN201511011772.6A patent/CN105462367A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102911560A (en) * | 2012-11-12 | 2013-02-06 | 山西大学 | Dustless colored chalk dedicated for whiteboard capable of fading chemically |
| CN103468062A (en) * | 2013-08-30 | 2013-12-25 | 龙启知 | Neodymium iron boron magnetic chalk |
Non-Patent Citations (1)
| Title |
|---|
| 袁震等: "疏水超顺磁性四氧化三铁纳米粒子的制备与表征", 《广东化工》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2019019722A1 (en) * | 2017-07-25 | 2019-01-31 | 中国科学院上海硅酸盐研究所 | Chalk for ceramic painting/marking and preparation method therefor |
| CN114031980A (en) * | 2021-12-23 | 2022-02-11 | 浙江理工大学 | Magnetic wax crayon capable of writing |
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Application publication date: 20160406 |