Non-baked pencil lead

Abstract

To provide a non-fired pencil lead in which the gloss of a drawn line is not conspicuous even when viewed from any direction and a drawn line having no difference between a coated color and a visible hue can be obtained.SOLUTION: The non-fired pencil lead includes: a wax that is solid at normal temperature; a coloring material; an extender; a water-soluble resin; and a cellulose fiber, wherein a proportion of a scaly substance in the extender is 20 mass% or less, and a proportion of massive particles in the extender is 80 mass% or more.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to non-baked pencil leads. [Background technology]

[0002] Until now, the development of non-baked pencil leads, such as colored pencil leads, has focused on improving the color of the drawn line, the writing feel, and strengthening the tip strength of the lead. Typically, gloss is added to the drawn line by using wax as the main material of the colored pencil lead. For example, the colored pencil described in Patent Document 1, which can also be used in cosmetics, has a formulation and manufacturing method that takes into consideration issues such as color transfer.

[0003] Meanwhile, Patent Document 2 discloses a crayon containing calcium carbonate as a hardener. Patent Document 3 discloses a solid drawing material containing calcium carbonate, talc, and barium sulfate as extenders. Patent Document 4 discloses a non-baked pencil lead containing calcium carbonate, kaolin, talc, precipitated barium sulfate, mica, and potassium titanate whiskers as extenders. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Special Publication No. 2005-514463 [Patent Document 2] Japanese Patent Publication No. 52-41028 [Patent Document 3] Japanese Patent Application Publication No. 57-153060 [Patent Document 4] Japanese Patent Application Laid-Open No. 2008-45043 Summary of the Invention [Problem to be solved by the invention]

[0005] Patent Document 1 describes how the gloss of a line can be adjusted by changing the type of wax added to a color pencil. However, it does not describe a formula that produces no gloss at all. Glossy lines can have the problem of appearing different from their actual hue depending on the angle at which the gloss appears, a problem that is often brought to mind when viewing artworks at exhibitions. In recent years, it has become common for artists to photograph their own pencil or colored pencil drawings with a smartphone or other camera and post them on social media. When photographing, if the angle between the light and the camera is not properly adjusted, the lines will shine, and the hues may not appear properly in the image.

[0006] The graphite particles contained in the pencil lead are one of the reasons for the glossiness of the drawn lines. In addition, in conventional colored pencils, the extenders blended in addition to the waxes, especially talc, are thin and flaky, which reflect light depending on the angle of the light source, causing glossiness.

[0007] An object of the present invention is to provide a non-baked pencil lead that produces drawn lines with an inconspicuous gloss when viewed from any direction and with a hue that is consistent with the applied color. [Means for solving the problem]

[0008] The non-baked pencil lead of an embodiment of the present application comprises a wax that is solid at room temperature, a coloring material, a filler material, a water-soluble resin, and cellulose fiber, and is characterized in that the proportion of scale-like substances in the filler material is 20% by mass or less, and the proportion of aggregate particles in the filler material is 80% by mass or more.

[0009] Here, it is desirable to use at least one of the group consisting of calcium carbonate, magnesium sulfate, aluminum hydroxide, and magnesium carbonate as the aggregate particles.

[0010] Furthermore, it is desirable that the filler has a visual reflectance, defined as the ratio of the incident light intensity at an angle of 45° to the reflected light intensity at an angle of 90°, of less than 0.1, on a smooth surface formed by mixing molten sumac wax and the filler in a mass ratio of 1:1 and bringing the mixture into contact with a glass surface to solidify. [Effects of the Invention]

[0011] The embodiment of the present application is configured as described above, and therefore can provide a non-baked pencil lead that produces drawn lines with an inconspicuous gloss when viewed from any direction and with no difference in hue between the painted color and the visible color. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a perspective view schematically illustrating the appearance of a non-baked pencil lead according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0013] The non-baked pencil lead of an embodiment of the present application contains wax that is solid at room temperature, a color material, a filler material, a water-soluble resin, and cellulose fiber, and the proportion of scale-like substances in the filler material is 20% by mass or less, and the proportion of aggregate particles in the filler material is 80% by mass or more.

[0014] Here, the term "scaly substance" refers to a flaky mineral substance with an aspect ratio of 2 or more, and examples include talc, kaolin, mica, and boron nitride. The thickness of the scaly substance can be, for example, less than 5 μm. In other words, the scaly substance as an extender material is prone to reflecting light, which causes the gloss of drawn lines. In the non-baked pencil lead of the present embodiment, the proportion of this scaly substance in the extender material is 20% by mass or less, and the proportion of agglomerated particles that do not reflect light is 80% by mass or more, thereby suppressing the gloss of drawn lines.

[0015] It is desirable that no scale-like substance is contained as an extender, but if the proportion of scale-like substance in the extender is 20% by mass or less, the gloss of the drawn lines is sufficiently suppressed. Note that when no scale-like substance is contained as an extender, i.e., when the proportion is 0% by mass, it is desirable that the aggregate particles account for the total amount of the extender, i.e., 100% by mass.

[0016] The aggregate particles as the filler are preferably at least one selected from the group consisting of calcium carbonate, magnesium sulfate, aluminum hydroxide, and magnesium carbonate.Furthermore, the filler has a luminous reflectance of less than 0.1, which is defined as the ratio of the intensity of incident light irradiated at an angle of 45° to the intensity of reflected light at an angle of 90°, when the smooth surface is formed by mixing molten sumac wax and the filler in a mass ratio of 1:1 and bringing the mixture into contact with a glass surface to solidify.

[0017] Waxes that are solid at room temperature refer to waxes with a melting point of 45°C or higher, for example. For example, stearic acid glyceride with a melting point of 61°C, paraffin wax 135F with a melting point of 57°C, microcrystalline wax with a melting point of 84°C, and rosin ester with a softening point of 76°C can be used as waxes in the present embodiment. In addition, waxes classified as glycerin fatty acid esters and pentaerythritol fatty acid esters with a melting point of 45°C or higher can also be used as waxes in the present embodiment.

[0018] Coloring materials can be pigments or dyes commonly used in colored pencils. Examples of pigments include graphite, titanium oxide, iron black, carbon black, Prussian blue, ultramarine, Blue No. 1, red iron oxide, yellow iron oxide, chromium oxide, chromium hydroxide, zinc oxide, zirconium oxide, cobalt oxide, fish scale foil, bismuth oxychloride, and titanium mica; azo organic pigments such as Disazo Yellow AAA and Pyrazolone Orange; cyanine organic pigments such as Phthalocyanine Blue and Phthalocyanine Green; high-grade organic pigments such as Quinacridone Red; dye pigments such as Fanal Color; and fluorescent pigments. In addition to pigments, dyes such as Blue No. 2, Blue No. 404, Red No. 2, Red No. 3, Red No. 102, Red No. 104, Red No. 105, Red No. 106, DPP Red, Yellow No. 4, Yellow No. 5, and Green No. 3 can also be used, either alone or in combination.

[0019] The water-soluble resin is used as a binder, and water-soluble organic polymers such as sodium carboxymethylcellulose, ammonium carboxycellulose, polyvinyl alcohol, and methylcellulose can be used.

[0020] The cellulose fiber is made by pulverizing natural wood cellulose and preferably has an average particle size of 100 μm or less. The cellulose fiber is contained in the non-baked pencil lead of this embodiment to increase the mechanical strength.

[0021] The non-baked pencil lead of this embodiment can be manufactured, for example, by the following manufacturing method. That is, an equal mass of water is added to a mixture of wax, colorant, extender, water-soluble resin, and cellulose fiber, and the mixture is mixed and dispersed in a kneader. The mixture is then kneaded with a twin-roll mill to adjust the moisture content. The resulting mixture is pelletized and extruded into a pencil lead of the desired diameter using a single-screw extruder. The molded lead is then dried to remove moisture, resulting in a non-baked pencil lead 10 having a roughly cylindrical lead body 11, as shown in FIG. 1.

[0022] Lines drawn with the non-baked pencil lead manufactured as described above contain a low content of the scale-like substance that causes gloss in the extender, so the gloss is not noticeable no matter what camera angle the photograph is taken from, and the original color is well expressed in the photographed image. In addition, the loss of mechanical strength caused by the bulk of the extender being made up of agglomerated particles is reinforced by the inclusion of cellulose fiber. [Example]

[0023] (1) Body material We investigated how the visual reflectance of the filler varies depending on the blending ratio of calcium carbonate, barium sulfate, aluminum hydroxide, or magnesium carbonate as the aggregate particles that are the raw materials of the filler, and talc as the scaly substance.

[0024] The calcium carbonate, barium sulfate, aluminum hydroxide, and magnesium carbonate used had average particle sizes of 3.2 μm, 1 μm, 1.4 μm, and 5 μm, respectively. The average particle size of the talc flakes was 10 μm.

[0025] As fillers, calcium carbonate and talc were blended in the blending ratios shown in Recipes 1-1 to 1-7 in Table 1 below, barium sulfate and talc were blended in the blending ratios shown in Recipes 2-1 to 2-7 in Table 2 below, aluminum hydroxide and talc were blended in the blending ratios shown in Recipes 3-1 to 3-7 in Table 3 below, and magnesium carbonate and talc were blended in the blending ratios shown in Recipes 4-1 to 4-7 in Table 4 below.

[0026] Each filler powder was mixed with molten sumac wax at a 1:1 mass ratio. The molten wax mixture was then poured into a glass petri dish, cooled, solidified, and formed into pellets measuring 20 mm in diameter and 5 mm thick to prepare measurement samples. The smooth surface of the sample that came into contact with the glass surface was used as the measurement surface. The sample was placed face up, and the luminous reflectance, defined as the ratio of the reflected light intensity at a 90° angle to the incident light intensity irradiated at a 45° angle relative to the measurement surface, was measured using a PD-7 (Konica Minolta). The results are also shown in Tables 1 and 2.

[0027] [Table 1]

[0028] [Table 2]

[0029] [Table 3]

[0030] [Table 4]

[0031] As shown in Tables 1 and 2 above, it was found that regardless of whether the aggregate particles blended as an extender are calcium carbonate, barium sulfate, aluminum hydroxide, or magnesium carbonate, the luminous reflectance is less than 0.1 as long as the blending ratio of talc is 20% by mass or less. From this, it was inferred that, from the perspective of suppressing the gloss of drawn lines, the appropriate ratio of talc as a scaly substance in the extender is 20% by mass or less.

[0032] (2) Raw materials The non-baked pencil leads in each Example and Comparative Example had the following composition: Stearic acid glyceride (Poem V-200, Riken Vitamin) with a melting point of 61°C and rosin ester with a softening point of 76°C were used as the wax, and sodium carboxymethylcellulose (F10MC, Nippon Paper Industries Co., Ltd.) was used as the water-soluble resin. The black pigment was carbon black (MA-100, Mitsubishi Chemical), the blue pigment was phthalocyanine blue (CHROMOFINE Blue HS-3, Dainichiseika Color & Chemicals Mfg. Co., Ltd.), the red pigment was permanent red (SEIKAFAST RED 4R-4016, Dainichiseika Color & Chemicals Mfg. Co., Ltd.), and the green pigment was phthalocyanine green (CHROMOFINE GREEN 2GO, Dainichiseika Color & Chemicals Mfg. Co., Ltd.). Titanium dioxide (JR-701, Teika) and lithopone (B311, ANHUI UNION TITANIUM ENTERPRISE) were used as white pigments to enhance brightness. The fillers used were calcium carbonate (PC calcium carbonate, Shiraishi Kogyo Co., Ltd.), barium sulfate (P-30, Takehara Chemical Industry Co., Ltd.), aluminum hydroxide (RH-30, Iwatani Corporation), magnesium carbonate (MS-S, Konoshima Chemical Industry Co., Ltd.), and talc (Himicron, Takehara Chemical Industry Co., Ltd.), or a combination of two or more of these. KC Flock W-50 (Nippon Paper Industries) was used as the cellulose fiber, and basic magnesium sulfate (MOS-HIGE, Ube Materials) was used as the auxiliary additive.

[0033] (2-1) Example 1 The composition of Example 1 as a blue pencil lead was 33% by mass of glyceride stearate, 2% by mass of rosin ester, 4% by mass of sodium carboxymethylcellulose, 10% by mass of phthalocyanine blue and 10% by mass of titanium dioxide as colorants, 36% by mass of barium sulfate as an extender, and 5% by mass of cellulose fiber.

[0034] (2-2) Example 2 The composition of Example 2 as a red pencil lead was 33% by mass of glyceride stearate, 2% by mass of rosin ester, 4% by mass of sodium carboxymethylcellulose, 10% by mass of permanent red and 10% by mass of titanium dioxide as colorants, 36% by mass of barium sulfate as an extender, and 5% by mass of cellulose fiber.

[0035] (2-3) Example 3 The composition of Example 3 as a green pencil lead was 33% by mass of glyceride stearate, 2% by mass of rosin ester, 4% by mass of sodium carboxymethylcellulose, 10% by mass of phthalocyanine green and 10% by mass of titanium dioxide as colorants, 36% by mass of barium sulfate as an extender, and 5% by mass of cellulose fiber.

[0036] (2-4) Example 4 The composition of Example 4 as a black pencil lead was 33% by mass of glyceride stearate, 2% by mass of rosin ester, 4% by mass of sodium carboxymethylcellulose, 15% by mass of carbon black as a coloring material, 41% by mass of calcium carbonate as an extender, and 5% by mass of cellulose fiber.

[0037] (2-5) Example 5 The composition of Example 5 as a black pencil lead was 33% by mass of glyceride stearate, 2% by mass of rosin ester, 4% by mass of sodium carboxymethylcellulose, 15% by mass of carbon black as a coloring material, 36% by mass of calcium carbonate, 5% by mass of cellulose fiber, and 5% by mass of basic magnesium sulfate as extenders.

[0038] (2-6) Example 6 The composition of Example 6 as a black pencil lead was 33% by mass of glyceride stearate, 2% by mass of rosin ester, 4% by mass of sodium carboxymethylcellulose, 15% by mass of carbon black as a coloring material, 33% by mass of barium sulfate as an extender, 8% by mass of cellulose fiber, and 5% by mass of basic magnesium sulfate.

[0039] (2-7) Example 7 The composition of Example 7 as a black pencil lead was 33% by mass of glyceride stearate, 2% by mass of rosin ester, 4% by mass of sodium carboxymethylcellulose, 15% by mass of carbon black as a coloring material, 5% by mass of talc and 36% by mass of calcium carbonate as extenders, and 5% by mass of cellulose fiber.

[0040] (2-8) Example 8 The composition of Example 8 as a blue pencil lead was 33% by mass of glyceride stearate, 2% by mass of rosin ester, 4% by mass of sodium carboxymethylcellulose, 10% by mass of phthalocyanine blue and 10% by mass of lithopone as colorants, 36% by mass of barium sulfate as an extender, and 5% by mass of cellulose fiber.

[0041] (2-9) Example 9 The composition of Example 9 as a black pencil lead was 33% by mass of glyceride stearate, 2% by mass of rosin ester, 4% by mass of sodium carboxymethylcellulose, 15% by mass of carbon black as a coloring material, 38% by mass of aluminum hydroxide as an extender, and 8% by mass of cellulose fiber.

[0042] (2-10) Example 10 The composition of Example 10 as a black pencil lead was 33% by mass of glyceride stearate, 2% by mass of rosin ester, 4% by mass of sodium carboxymethylcellulose, 15% by mass of carbon black as a coloring material, 38% by mass of magnesium carbonate as an extender, and 8% by mass of cellulose fiber.

[0043] (2-11) Comparative Example 1 The composition of Comparative Example 1 as a black pencil lead was 33% by mass of glyceride stearate, 2% by mass of rosin ester, 4% by mass of sodium carboxymethylcellulose, 15% by mass of carbon black as a coloring material, 10% by mass of talc and 31% by mass of calcium carbonate as extenders, and 5% by mass of cellulose fiber.

[0044] (2-12) Comparative Example 2 The composition of Comparative Example 2 as a black pencil lead was 33% by mass of glyceride stearate, 2% by mass of rosin ester, 4% by mass of sodium carboxymethylcellulose, 15% by mass of carbon black as a coloring material, 20% by mass of talc and 21% by mass of calcium carbonate as extenders, and 5% by mass of cellulose fiber.

[0045] (2-13) Comparative Example 3 The composition of the black pencil lead of Comparative Example 3 was 33% by mass of glyceride stearate, 2% by mass of rosin ester, 4% by mass of sodium carboxymethylcellulose, 15% by mass of carbon black as a coloring material, 41% by mass of talc as an extender, and 5% by mass of cellulose fiber.

[0046] (2-14) Comparative Example 4 The composition of the black pencil lead of Comparative Example 4 was 33% by mass of glyceride stearate, 2% by mass of rosin ester, 4% by mass of sodium carboxymethylcellulose, 15% by mass of carbon black as a coloring material, and 46% by mass of calcium carbonate as an extender.

[0047] (2-15) Comparative Example 5 The composition of Comparative Example 5 as a blue pencil lead was 33% by mass of glyceride stearate, 2% by mass of rosin ester, 4% by mass of sodium carboxymethylcellulose, 10% by mass of phthalocyanine blue and 10% by mass of titanium dioxide as coloring materials, and 41% by mass of talc as an extender.

[0048] (2-16) Comparative Example 6 The composition of the red pencil lead of Comparative Example 6 was 33% by mass of glyceride stearate, 2% by mass of rosin ester, 4% by mass of sodium carboxymethylcellulose, 10% by mass of permanent red and 10% by mass of titanium dioxide as coloring materials, and 41% by mass of talc as an extender.

[0049] (2-17) Comparative Example 7 The composition of Comparative Example 7 as a green pencil lead was 33% by mass of glyceride stearate, 2% by mass of rosin ester, 4% by mass of sodium carboxymethylcellulose, 10% by mass of phthalocyanine green and 10% by mass of titanium dioxide as colorants, and 41% by mass of talc as an extender.

[0050] (3) Manufacturing of non-baked pencil leads The raw materials of each of the above Examples 1 to 10 and Comparative Examples 1 to 7 were mixed in a kneader with the same mass of water, and then the moisture content was adjusted while kneading with a twin roll mill. This mixture was pelletized and formed into thin wires using a single-screw extruder. Examples 1 to 3, 8, and Comparative Examples 5 to 7 were dried at 45°C for 24 hours to remove moisture, while Examples 4 to 7, 9, and 10, and Comparative Examples 1 to 4 were dried at 50°C for 24 hours to remove moisture, resulting in 2.5 mm diameter blue non-baked pencil leads (Examples 1 and 8, and Comparative Example 5), red non-baked pencil leads (Example 2 and Comparative Example 6), green non-baked pencil leads (Example 3 and Comparative Example 7), and black non-baked pencil leads (Examples 4 to 7, 9, and 10, and Comparative Examples 1 to 4).

[0051] (4) Line drawing The hand-drawn lines were created using the sample creation method specified in JIS S 6006:2020, 8.9a. Specifically, the drawing paper (basis weight 78.3 to 205 g / m) was spread on a flat glass plate. 2 A measurement sample was prepared by repeatedly hand-painting a non-baked pencil lead onto a sheet of paper (whiteness of 75% or more) in both the left-right and top-bottom directions so that the paper surface was uniformly filled in.

[0052] The machine-drawn lines were created using Method A specified in 8.7.2 of JIS S 6006:2020. Specifically, measurement samples were created by drawing spiral lines resembling record grooves on drawing paper using a record-type drawing machine equipped with a non-baked pencil lead, according to the following writing conditions. Drawing paper: basis weight 128±5g / m 2 Kent Paper Writing load: 3N Writing speed: 3.0m / min Line pitch: 0.5 mm Image distance: 6±1m Writing angle: 75° Tip shape of core: truncated cone shape with a taper angle of 17±1° and a tip diameter of 0.6±0.1mm Core rotation: once per rotation of the stroke

[0053] (5) Brightness measurement The brightness was measured as follows: For each of the examples and comparative examples, hand-drawn lines and instrument-drawn lines were measured using a color meter (SC-P, Suga Test Instruments Co., Ltd.).

[0054] (6) Gloss measurement The gloss was measured as follows: For each example and comparative example, the gloss at 60° and 85° to the hand-drawn line and the machine-drawn line was measured using a digital variable angle gloss meter UGV-5 (manufactured by Suga Test Instruments Co., Ltd.).

[0055] (7) Bending strength measurement Ten non-baked pencil leads from each of the above examples and comparative examples were subjected to a bending strength test according to JIS S 6006:2020, 8.6, and the average value was calculated. Specifically, a Tensilon universal material testing machine (RTC-1150A, Orientec) was used to apply a load at 10 mm / min to the center of a non-baked pencil lead supported at a fulcrum distance of 60 mm. The load (F, unit: N) at which the non-baked pencil lead broke was measured, and the bending strength (σ, unit: MPa) was calculated using the following formula (1). The tip where the load was applied and the tips of both fulcrums were arc-shaped, with a radius (R) of R = 0.2 ± 0.02 (mm).

[0056] σ=8Fl / πd 3 ...Equation (1)

[0057] In the above formula (1), "l" is the distance between the fulcrums (mm), which is 60 mm in this case. Also, "d" in the above formula is the diameter (mm) of the unbaked pencil lead, which is 2.5 mm in this case. The bending strength was measured immediately after production.

[0058] (8) Measurement results For each of the above examples and comparative examples, the results of brightness measurement, gloss measurement, and bending strength measurement are shown in Table 5 below.

[0059] [Table 5]

[0060] First, Examples 1 and 8, which have the same hue, are compared with Comparative Example 5, Example 2 and Comparative Example 6, and Example 3 and Comparative Example 7. In all Examples, the proportion of barium sulfate, which is an aggregated particle, in the filler was 100% by mass, while in all Comparative Examples, the proportion of talc, which is a scaly substance, in the filler was 100% by mass. Furthermore, in all Comparative Examples, the gloss value at 85° in hand-drawn lines exceeded 10, and in Comparative Examples 5 and 7, the gloss value at 85° also exceeded 10 in machine-drawn lines. In contrast, in all Examples, the gloss value measured under all conditions was below 10. Furthermore, there was no clear difference in lightness between the Examples and Comparative Examples. From the above, it was found that in colored non-baked pencil leads, replacing the scaly substance in the filler with aggregated particles suppressed gloss without affecting lightness.

[0061] Although both Examples 1 and 8 had the same blue color, different white pigments, titanium dioxide and lithopone, were used. However, there was no significant difference in the measurement results. Therefore, it was inferred that lithopone can be used as a white pigment instead of titanium dioxide.

[0062] Next, we will examine Examples 4 to 7, 9, and 10, as well as Comparative Examples 1 to 3, which are black non-baked pencil leads. In all Examples, the proportion of calcium carbonate, barium sulfate, aluminum hydroxide, or magnesium carbonate, which are aggregate particles, in the filler was 80% by mass or more, while in all Comparative Examples, the proportion of talc, which is a scaly substance, in the filler was 20% by mass or more. That is, the proportion of talc in the filler was 0% by mass in Examples 4 to 6, 9, and 10, and 12.2% by mass (talc 5% by mass, calcium carbonate 36% by mass) in Example 7. In contrast, the proportions were 24.4% by mass (talc 10% by mass, calcium carbonate 31% by mass) in Comparative Example 1, 48.8% by mass (talc 20% by mass, calcium carbonate 21% by mass) in Comparative Example 2, and 100% by mass in Comparative Example 3.

[0063] In Comparative Examples 1 to 3, the gloss value at 85° in machine-drawn lines exceeded 10, and in Comparative Examples 2 and 3, the gloss value at 85° in hand-drawn lines also exceeded 10, and in Comparative Example 3, the gloss value also exceeded 10 at 60°. In contrast, in Examples 4 to 7, 9, and 10, the gloss value measured under all conditions was below 10. There was no clear difference in brightness between the Examples and Comparative Examples. From the above, it was found that even in non-baked pencil leads used as black pencil leads, gloss was suppressed without affecting brightness by replacing the scaly substance in the filler with aggregated particles.

[0064] In Comparative Example 4, the proportion of calcium carbonate in the filler was 100% by mass, but since it did not contain cellulose fiber, the bending strength was significantly reduced. This shows that the mechanical strength of the non-baked pencil lead, which was previously provided by talc as a filler, is compensated for by the cellulose fiber. [Industrial Applicability]

[0065] The present invention can be used as a non-baked pencil lead. [Explanation of symbols]

[0066] 10 Non-baked pencil lead 11 Lead body

Claims

1. The composition contains a wax that is solid at room temperature, a coloring material, an extender, a water-soluble resin, and cellulose fiber, the proportion of the scale-like substance in the filler is 20% by mass or less, and the proportion of the aggregate particles in the filler is 80% by mass or more; The filler is a non-baked pencil lead in which the luminous reflectance, defined as the ratio of the intensity of incident light irradiated at an angle of 45° to the intensity of reflected light at an angle of 90°, is less than 0.1 when the smooth surface is formed by mixing molten sumac wax and the filler in a mass ratio of 1:1 and bringing the mixture into contact with a glass surface to solidify.

2. 2. The non-fired pencil lead of claim 1, wherein the agglomerated particles are at least one of the group consisting of calcium carbonate, magnesium sulfate, aluminum hydroxide, and magnesium carbonate.

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