CN113930099A - Low-cost and environment-friendly pencil lead and preparation method and application thereof - Google Patents
Low-cost and environment-friendly pencil lead and preparation method and application thereof Download PDFInfo
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- CN113930099A CN113930099A CN202111330789.3A CN202111330789A CN113930099A CN 113930099 A CN113930099 A CN 113930099A CN 202111330789 A CN202111330789 A CN 202111330789A CN 113930099 A CN113930099 A CN 113930099A
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- pencil lead
- molecular weight
- graphite powder
- pencil
- weight polyethylene
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- 238000002360 preparation method Methods 0.000 title claims abstract description 17
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 43
- 239000004699 Ultra-high molecular weight polyethylene Substances 0.000 claims abstract description 38
- 229920000785 ultra high molecular weight polyethylene Polymers 0.000 claims abstract description 38
- 239000002994 raw material Substances 0.000 claims abstract description 20
- 238000000034 method Methods 0.000 claims abstract description 10
- 230000006835 compression Effects 0.000 claims description 5
- 238000007906 compression Methods 0.000 claims description 5
- 238000012360 testing method Methods 0.000 abstract description 10
- 238000005299 abrasion Methods 0.000 abstract description 7
- 238000002835 absorbance Methods 0.000 abstract description 5
- 238000004040 coloring Methods 0.000 abstract description 5
- 230000000694 effects Effects 0.000 abstract description 4
- 238000002156 mixing Methods 0.000 abstract description 4
- 238000005265 energy consumption Methods 0.000 abstract description 3
- 238000001816 cooling Methods 0.000 abstract description 2
- 229910002804 graphite Inorganic materials 0.000 description 7
- 239000010439 graphite Substances 0.000 description 7
- 238000004519 manufacturing process Methods 0.000 description 7
- 239000011347 resin Substances 0.000 description 7
- 229920005989 resin Polymers 0.000 description 7
- 239000000203 mixture Substances 0.000 description 6
- 238000012545 processing Methods 0.000 description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 2
- 239000011230 binding agent Substances 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- YADSGOSSYOOKMP-UHFFFAOYSA-N dioxolead Chemical compound O=[Pb]=O YADSGOSSYOOKMP-UHFFFAOYSA-N 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000003912 environmental pollution Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 239000003960 organic solvent Substances 0.000 description 2
- 239000004372 Polyvinyl alcohol Substances 0.000 description 1
- 239000004927 clay Substances 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 235000014113 dietary fatty acids Nutrition 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000000194 fatty acid Substances 0.000 description 1
- 229930195729 fatty acid Natural products 0.000 description 1
- -1 fatty acid ester Chemical class 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- 238000004898 kneading Methods 0.000 description 1
- 239000011133 lead Substances 0.000 description 1
- 239000000314 lubricant Substances 0.000 description 1
- 239000011812 mixed powder Substances 0.000 description 1
- 239000002105 nanoparticle Substances 0.000 description 1
- QIQXTHQIDYTFRH-UHFFFAOYSA-N octadecanoic acid Chemical compound CCCCCCCCCCCCCCCCCC(O)=O QIQXTHQIDYTFRH-UHFFFAOYSA-N 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 239000002574 poison Substances 0.000 description 1
- 231100000614 poison Toxicity 0.000 description 1
- 229920002635 polyurethane Polymers 0.000 description 1
- 239000004814 polyurethane Substances 0.000 description 1
- 229920002451 polyvinyl alcohol Polymers 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- 235000012239 silicon dioxide Nutrition 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 239000004408 titanium dioxide Substances 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
Images
Classifications
-
- 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 belongs to the technical field of pencils, and particularly relates to a low-cost and environment-friendly pencil lead as well as a preparation method and application thereof. The pencil lead provided by the invention comprises the following raw materials in percentage by mass: 35-72% of graphite powder and 28-65% of ultra-high molecular weight polyethylene. The preparation method of the pencil lead comprises the following steps: uniformly mixing graphite powder and ultrahigh molecular weight polyethylene, pouring into a die cavity, compacting, baking at the baking temperature of 180-220 ℃ for 5-10 minutes, cooling and demolding to obtain the graphite powder. The method has the advantages of simple process, low energy consumption, no emission and quick forming. The pencil lead manufactured by the invention is compact and writing-resistant, and has low cost and convenient and quick use. Tests show that the appearance, the size specification, the drop test, the hardness, the stress of the core tip, the abrasion and the absorbance of the pencil core prepared by the invention all accord with the standard, and the pencil core has good strength and coloring effect and good scribbling performance.
Description
Technical Field
The invention relates to the technical field of pencils, in particular to a low-cost and environment-friendly pencil lead and a preparation method and application thereof.
Background
The pencil is a special pen for writing and drawing sketches, and the pencil lead is an essential important accessory. The traditional pencil lead is processed by mixing graphite, clay and water according to a certain proportion, extruding a certain specification and size through a lead pressing machine after mixing by a kneading machine and a three-roller machine, heating (50-150 ℃) for drying and roasting at high temperature (800-1100 ℃), and finally performing oil immersion treatment. The traditional process has high energy consumption, long production period, high cost and great environmental pollution in the production process. With the development of the pencil manufacturing technology, resin pencil leads, including common resin pencil leads and water-soluble resin pencil leads, appear on the market. The common resin pencil lead is produced by dissolving resin by an organic solvent and then mixing the resin with graphite, the production process is complex, the production period is long, and toxic and harmful organic solvents are used in the processing process, so that a series of safety problems such as operator poison and environmental pollution are easily caused. The water-soluble resin pencil lead adopts raw materials such as polyvinyl alcohol, waterborne polyurethane and the like as a binder, stearate, fatty acid ester and the like are often added as a lubricant for improving the coloring performance of the pencil lead, and silicon dioxide, titanium dioxide and other nano particles are often added for improving the strength of the pencil lead, so that the formula is complex, the raw materials are required to be added in batches during preparation, different processing conditions are set, and the process is also complex.
Therefore, under the current production situation of reducing energy and reducing consumption and paying attention to environmental protection, the study on the pencil lead which is simple in formula, simple in processing technology, short in production period and more environment-friendly is urgently needed.
Disclosure of Invention
According to the first aspect of the invention, a low-cost and environment-friendly pencil lead is provided, which is composed of the following raw materials in percentage by mass: 25 to 50 percent of graphite powder and 50 to 75 percent of ultra-high molecular weight polyethylene. Wherein, the ultra-high molecular weight polyethylene is used as a binder to play a role in binding graphite powder. Because the ultra-high molecular weight polyethylene has no fluidity after being melted, the original form is kept, the graphite is not coated, the coating performance of the graphite is not influenced, and the ultra-high molecular weight polyethylene has certain cohesiveness and can bond the graphite together, so the ultra-high molecular weight polyethylene can fully exert the coating performance of the graphite.
When the content of the graphite powder is low and the content of the ultra-high molecular weight polyethylene is high, the strength of the obtained pencil lead is better; when the graphite powder content is high and the ultra-high molecular weight polyethylene content is low, the obtained pencil lead has a good coloring effect. Therefore, the use amounts of the graphite powder and the ultra-high molecular weight polyethylene can be determined according to actual requirements.
In some embodiments, the composition consists of the following raw materials in percentage by mass: 75% of graphite powder and 25% of ultra-high molecular weight polyethylene.
In some embodiments, the composition consists of the following raw materials in percentage by mass: 70% of graphite powder and 30% of ultra-high molecular weight polyethylene.
In some embodiments, the composition consists of the following raw materials in percentage by mass: 65% of graphite powder and 35% of ultra-high molecular weight polyethylene.
In some embodiments, the composition consists of the following raw materials in percentage by mass: 60% of graphite powder and 40% of ultra-high molecular weight polyethylene.
In some embodiments, the composition consists of the following raw materials in percentage by mass: 55% of graphite powder and 45% of ultra-high molecular weight polyethylene.
In some embodiments, the graphite powder has a fineness of 50 to 150 mesh and the ultra-high molecular weight polyethylene has a molecular weight of 250 to 350 ten thousand. Preferably, the fineness of the graphite powder is about 100 meshes, and the molecular weight of the ultrahigh molecular weight polyethylene is about 300 ten thousand. Thus, the writing performance of the obtained pencil lead is optimal.
According to a second aspect of the invention, the preparation method of the low-cost and environment-friendly pencil lead is provided, wherein graphite powder and ultra-high molecular weight polyethylene are uniformly mixed, poured into a mold cavity, compacted and then baked, the baking temperature is 180-220 ℃, the baking time is 5-10 minutes, and the pencil lead is obtained after cooling and demolding.
In some embodiments, the baking temperature is 190 ℃ and the baking time is 8 minutes.
In some embodiments, the compression ratio is (1.8-2.2): 1. The compression ratio referred to in the invention is: the bulk ratio of the mixed powder of graphite powder and ultra-high molecular weight polyethylene before and after compression in the die cavity.
In some embodiments, the pencil lead is cylindrical, square cylindrical, elongated with one end tapered. In order to obtain pencil leads with different shapes, molds with different structures are required to be used for preparation, and the structure of the mold is required to be selected according to the shape and the model size of the pencil lead.
According to a third aspect of the present invention, there is provided the use of a low cost, environmentally friendly pencil lead as described above in the preparation of a pencil. Specifically, when the pencil lead is cylindrical or square-column-shaped, the pencil lead can be embedded in the middle of the wood strip and assembled into a pencil according to the prior art; when the pencil lead is in a long strip shape with one conical end, the pencil lead can be inlaid on the penholder and assembled into a pencil according to the prior art.
The preparation method has the advantages of simple process, low energy consumption, no emission and quick forming. The pencil lead prepared by the invention is compact and writing-resistant, and has low cost and convenient and quick use.
Tests show that the appearance, the size specification, the drop test, the hardness, the stress of the pencil lead tip, the abrasion and the absorbance of the pencil lead prepared by the invention all accord with the standard, wherein the stress of the pencil lead tip of HB type pencil lead and F type pencil lead accord with the standard of high-grade products, which shows that the pencil lead of the invention has high strength; the concentration (absorbance) of HB type pencil leads and F type pencil leads is more than 0.3, which shows that the pencil lead has good coloring effect and good writing performance; the abrasion of HB type pencil leads and F type pencil leads both meet the high-grade product standard, which shows that the pencil leads of the invention are compact and have writing resistance.
Drawings
Fig. 1 is a schematic view of a pencil lead mold used in the preparation of pencil leads according to example 1 of the present invention.
Fig. 2 is a schematic structural view of a pencil lead prepared in example 1 of the present invention and a pencil assembled therewith.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings, and it should be noted that the following examples are only for better explaining the contents of the present invention, and do not limit the scope of the present invention. The process steps not disclosed in the examples are prior art. The following starting materials are all commercially available unless otherwise specified.
Example 1
The low-cost and environment-friendly pencil lead is prepared from the following raw materials in percentage by mass: 65% of graphite powder and 35% of ultra-high molecular weight polyethylene, wherein the fineness of the graphite powder is about 100 meshes, and the molecular weight of the ultra-high molecular weight polyethylene is about 300 ten thousand.
The preparation method comprises the following steps:
the pencil lead mold comprises a top mold 1, a mold cavity 2 and a bottom mold 3, the structure is schematically shown in figure 1, the mold cavity 2 and the bottom mold 3 are closed when the pencil lead is prepared, graphite powder and ultra-high molecular weight polyethylene are uniformly mixed and poured into the mold cavity 2, then a rod of the top mold 1 is aligned with the mold cavity 2 and pressed downwards, the compression ratio is 2:1, the compacted mixture is placed into an oven for baking, the baking temperature is 190 ℃, the baking time is 8 minutes, the mold is cooled and removed, and the long strip-shaped pencil lead with one conical end is obtained, and the structure is schematically shown in figure 2.
The prepared pencil lead is inlaid on a pencil holder and assembled into a pencil according to the prior art, and the structural schematic is shown in figure 2.
Example 2
The low-cost and environment-friendly pencil lead is prepared from the following raw materials in percentage by mass: 75% of graphite powder and 25% of ultra-high molecular weight polyethylene, wherein the fineness of the graphite powder is about 100 meshes, and the molecular weight of the ultra-high molecular weight polyethylene is about 300 ten thousand.
The preparation process is similar to example 1.
Example 3
The low-cost and environment-friendly pencil lead is prepared from the following raw materials in percentage by mass: 70% of graphite powder and 30% of ultra-high molecular weight polyethylene, wherein the fineness of the graphite powder is about 100 meshes, and the molecular weight of the ultra-high molecular weight polyethylene is about 300 ten thousand.
The preparation process is similar to example 1.
Example 4
The low-cost and environment-friendly pencil lead is prepared from the following raw materials in percentage by mass: 60% of graphite powder and 40% of ultra-high molecular weight polyethylene, wherein the fineness of the graphite powder is about 100 meshes, and the molecular weight of the ultra-high molecular weight polyethylene is about 300 ten thousand.
The preparation process is similar to example 1.
Example 5
The low-cost and environment-friendly pencil lead is prepared from the following raw materials in percentage by mass: 55% of graphite powder and 45% of ultrahigh molecular weight polyethylene, wherein the fineness of the graphite powder is about 100 meshes, and the molecular weight of the ultrahigh molecular weight polyethylene is about 300 ten thousand.
The preparation process is similar to example 1.
In order to test the performance of the pencil leads prepared in examples 1-5, the pencil leads prepared in examples 1-5 were taken and tested according to the method of GB/T26704-2011.
The standard GB/T26704-2011 describes that graphite pencils are classified into seventeen types of 6B, 5B, 4B, 3B, 2B, HB, F, H, 2H, 3H, 4H, 5H, 6H, 7H, 8H and 9H according to different hardness, wherein part of test standards of HB and F type pencil leads are shown in Table 1.
TABLE 1 test standards for HB and F pencil leads
The results of testing the pencil leads prepared in examples 1-5 are shown in Table 2.
TABLE 2 test results of the properties of the pencil leads prepared in examples 1 to 5
As can be seen from Table 2, the appearance, dimensional specifications, drop test, hardness, stress on the pencil tip, abrasion and absorbance of the pencil leads prepared in examples 1 to 5 all meet the standards, wherein the stress on the pencil tip of the HB type pencil lead is 11 to 12N, the stress on the pencil tip of the F type pencil lead is 13 to 14N, and the stress on the pencil tips of the HB type pencil lead and the F type pencil lead all meet the standards of high-grade products, which indicates that the pencil leads of the invention have high strength; the concentration (absorbance) of HB type pencil leads and F type pencil leads is more than 0.3, which shows that the pencil lead has good coloring effect and good writing performance; the abrasion of the HB type pencil lead is 1.1-1.5mm, the abrasion of the F type pencil lead is 1.1-1.2mm, and the abrasion of the HB type pencil lead and the F type pencil lead both meet the high-grade product standard, which indicates that the pencil lead is compact and writing-resistant.
What has been described above are merely some specific embodiments of the present invention. It will be apparent to those skilled in the art that various changes and modifications can be made without departing from the inventive concept thereof, and these changes and modifications can be made without departing from the spirit and scope of the invention.
Claims (10)
1. The pencil lead is characterized by comprising the following raw materials in percentage by mass: 50-75% of graphite powder and 25-50% of ultra-high molecular weight polyethylene.
2. The low-cost and environment-friendly pencil lead according to claim 1, characterized by comprising the following raw materials in percentage by mass: 75% of graphite powder and 25% of ultra-high molecular weight polyethylene.
3. The low-cost and environment-friendly pencil lead according to claim 1, characterized by comprising the following raw materials in percentage by mass: 70% of graphite powder and 30% of ultra-high molecular weight polyethylene.
4. The low-cost and environment-friendly pencil lead according to claim 1, characterized by comprising the following raw materials in percentage by mass: 65% of graphite powder and 35% of ultra-high molecular weight polyethylene.
5. The low-cost and environment-friendly pencil lead according to claim 1, characterized by comprising the following raw materials in percentage by mass: 60% of graphite powder and 40% of ultra-high molecular weight polyethylene.
6. The low-cost and environment-friendly pencil lead according to claim 1, characterized by comprising the following raw materials in percentage by mass: 55% of graphite powder and 45% of ultra-high molecular weight polyethylene.
7. The low-cost and environment-friendly pencil lead as defined in any one of claims 1 to 6, wherein the fineness of the graphite powder is 50 to 150 meshes, and the molecular weight of the ultra-high molecular weight polyethylene is 250 to 350 ten thousand.
8. A method for preparing a low-cost and environment-friendly pencil lead as defined in any one of claims 1 to 7, characterized in that graphite powder and ultra-high molecular weight polyethylene are mixed uniformly, poured into a mold cavity, compacted and then baked at 180 ℃ to 220 ℃ for 5 to 10 minutes, cooled and taken out of the mold to obtain the pencil lead.
9. The method for preparing the low-cost and environment-friendly pencil lead according to claim 8, wherein the compression ratio is (1.8-2.2): 1 when the pencil lead is compressed.
10. Use of the low-cost, environmentally friendly pencil lead of any one of claims 1-7 in the preparation of a pencil.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111330789.3A CN113930099A (en) | 2021-11-10 | 2021-11-10 | Low-cost and environment-friendly pencil lead and preparation method and application thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111330789.3A CN113930099A (en) | 2021-11-10 | 2021-11-10 | Low-cost and environment-friendly pencil lead and preparation method and application thereof |
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| Publication Number | Publication Date |
|---|---|
| CN113930099A true CN113930099A (en) | 2022-01-14 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111330789.3A Pending CN113930099A (en) | 2021-11-10 | 2021-11-10 | Low-cost and environment-friendly pencil lead and preparation method and application thereof |
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| Country | Link |
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BR102015032455A2 (en) * | 2015-01-09 | 2016-11-29 | Faber Castell Ag | filler or chalk containing graphite and a polymeric binder and pencil with a graphite filler |
| CN106215527A (en) * | 2016-08-22 | 2016-12-14 | 广州康瑞环保科技有限公司 | Filter medium, its sintering method and the sintering equipment of enforcement the method |
| CN108159783A (en) * | 2018-01-12 | 2018-06-15 | 广州康瑞环保科技有限公司 | Utilize the sintering method of self-heating sintered filter medium and the sintering equipment of implementation this method |
-
2021
- 2021-11-10 CN CN202111330789.3A patent/CN113930099A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BR102015032455A2 (en) * | 2015-01-09 | 2016-11-29 | Faber Castell Ag | filler or chalk containing graphite and a polymeric binder and pencil with a graphite filler |
| CN106215527A (en) * | 2016-08-22 | 2016-12-14 | 广州康瑞环保科技有限公司 | Filter medium, its sintering method and the sintering equipment of enforcement the method |
| CN108159783A (en) * | 2018-01-12 | 2018-06-15 | 广州康瑞环保科技有限公司 | Utilize the sintering method of self-heating sintered filter medium and the sintering equipment of implementation this method |
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Application publication date: 20220114 |
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