Non-calcined pencil lead

Abstract

A non-calcined pencil lead containing a colorant containing a pigment, a wax, a body material, and a water-soluble resin, the pigment containing both C.I. Pigment Yellow 74 (PY-74) and C.I. Pigment Red 254 (PR-254), the ratio of the total amount of PY-74 and PR-254 in the pigment being 50% by mass or more.

Description

Technical Field

[0001] The present invention relates to non-calcined pencil leads. Background Art

[0002] In the past, unburned pencil leads such as colored pencil leads have been designed to have smooth writing and excellent coloring properties as well as mechanical strength, as described in the technique disclosed in Japanese Patent Application Laid-Open No. 2008-45043. On the other hand, unburned pencil leads often contain a pigment as a colorant. WO 2013 / 099730 A1 discloses CI Pigment Yellow 74, an insoluble azo dye having excellent storage stability of a coloring composition. Summary of the invention

[0003] Problem that the invention aims to solve

[0004] An object of an embodiment of the present application is to provide a non-calcined pencil lead which has light fastness and coloring power and in which the color tone of a drawn line is unlikely to change over time.

[0005] Solutions for solving problems

[0006] The non-calcined pencil lead according to an embodiment of the present application contains: a colorant including a pigment, a wax, a body material, and a water-soluble resin, wherein the pigment includes both CI Pigment Yellow 74 (PY-74) and CI Pigment Red 254 (PR-254), and the total amount of the PY-74 and the PR-254 in the pigment is 50% by mass or more.

[0007] Here, it is desirable that the ratio of the PR-254 in the CI pigment red series pigment among the pigments is 50% by mass or more.

[0008] Effects of the Invention

[0009] Since the embodiment of the present application is configured as described above, it is possible to provide a non-calcined pencil lead which has light fastness and coloring power and in which the color tone of the drawn line is unlikely to change over time. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 This is a perspective view schematically showing the appearance of a non-calcined pencil lead according to an embodiment. DETAILED DESCRIPTION

[0011] The non-calcined pencil lead according to an embodiment of the present application contains: a colorant including a pigment, a wax, a body material, and a water-soluble resin, wherein the pigment includes both CI Pigment Yellow 74 (PY-74) and CI Pigment Red 254 (PR-254), and the total amount of PY-74 and PR-254 in the pigment is 50% by mass or more.

[0012] As pigments, PY-74 and PR-254 are included as described above. The unburned pencil lead containing PY-74 and PR-254 as colorants is excellent in light resistance and coloring power, and has the property of being less likely to discolor over time (hereinafter referred to as "discoloration resistance").

[0013] As the pigment, only PY-74 and PR-254 may be used, but the total ratio of PY-74 and PR-254 in the pigment is 50% by mass or more. Pigments other than these may be contained, for example, one or a mixture of two or more of CI Pigment Yellow 1 (PY-1), CI Pigment Yellow 154 (PY-154), CI Pigment Red 170 (PR-170), CI Pigment Red 48:2 (PR-48:2), CI Pigment Green 7 (PG-7), CI Pigment Blue 15 (PB-15) and CI Pigment Red 122 (PR-122).

[0014] When a CI Pigment Red pigment other than PR-254 (e.g., PR-170, PR-48:2, PR-122) is added to the pigment, it is desirable to make the ratio of PR-254 in the CI Pigment Red pigment 50 mass % or more from the viewpoint of discoloration resistance.

[0015] In addition to the above pigments, pigments other than PY-74 and PR-254 that are usually used for coloring colored pencils, such as 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, coloring pigments such as fanal colors, and fluorescent pigments may be contained.

[0016] In addition, as a colorant, in addition to the above-mentioned pigments, it can also contain one or a mixture of two or more of 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.

[0017] The wax refers to a substance generally classified as a wax among the constituent components of the non-calcined pencil lead. Specifically, rosin, paraffin, microcrystalline wax, lacquer wax, beeswax, wood wax, montan wax, hydrogenated castor oil, hydrogenated palm oil, fatty acid glyceride (e.g., stearic acid glyceride), polyglycerol fatty acid ester, etc. can be used as the wax in this embodiment.

[0018] The base material is a component that contributes to improving the strength of the unfired pencil lead and improving the writing properties. Specifically, talc, kaolin, mica, boron nitride, calcium carbonate, potassium titanate whiskers, etc. can be used as the base material in this embodiment.

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

[0020] In addition to the above, various additives may be used depending on the purpose. For example, in order to improve the strength, cellulose fibers as an additive may be used as a component of the non-calcined pencil lead together with the above components.

[0021] The non-calcined pencil lead of the present embodiment can be manufactured, for example, by the following manufacturing method. That is, an equal amount of water is added to a mixture of a colorant, wax, a body material, a water-soluble resin, and other additives as required, and the mixture is mixed and dispersed in a kneader, and then the water content is adjusted while kneading in a double-roll mill. The mixture obtained by the preparation is pelletized and extruded in a single-screw extruder to form a pencil lead of a desired thickness. Then, the formed lead is dried without calcining to remove the water content, thereby obtaining a pencil lead. Figure 1 The unfired pencil lead 10 shown has a core body 11 which is generally cylindrical in shape.

[0022] The lines drawn with the unfired pencil lead manufactured as described above have light fastness and coloring power, and the color tone of the lines is unlikely to change over time. Specific embodiments

[0024] (1) Orange non-calcined pencil lead

[0025] (1-1) Raw material composition

[0026] The lightfastness, tinting strength and discoloration resistance of the unburned pencil lead containing only CI pigment yellow and CI pigment red as colorants to present an orange color tone were verified. The raw material compositions of Examples 1 to 3 and Comparative Examples 1 and 2 described below were as shown in Table 1 below.

[0027] [Table 1]

[0028]

[0029] In Table 1, stearic acid glyceryl used was POEM V-200 (RIKEN VITAMIN CO., LTD., melting point 61°C), carboxymethyl cellulose sodium salt used was F10MC (Nippon Paper), and talc used was High Micron (Takehara Chemical Industry). The softening point of rosin is 76°C.

[0030] (1-2) Pigment composition

[0031] The details of the pigment compositions in Table 1 in Examples 1 to 3 and Comparative Examples 1 and 2 are shown in Table 2 below. All the pigments in Table 2 below are made of DCL.

[0032] [Table 2]

[0033]

[0034] (1-3) Manufacturing method

[0035] Based on the above composition, non-calcined pencil leads of Examples 1 to 3 and Comparative Examples 1 and 2 were manufactured according to the manufacturing method mentioned in the aforementioned embodiment.

[0036] The non-calcined pencil leads of Examples 1 to 3 and Comparative Examples 1 and 2 all contain a CI pigment yellow pigment and a CI pigment red pigment, and all show an orange color. In Examples 1 to 3, according to the ratio of PY-74 to PR-254, Example 1 shows a reddish orange, Example 3 shows a yellowish orange, and Example 2 shows an orange color in between. In addition, Examples 1 to 3 contain both PY-74 and PR-254, and the total content of PY-74 and PR-254 in the pigment is 50% by mass or more, which is 100% by mass. On the other hand, in Comparative Examples 1 and 2, neither PY-74 nor PR-254 is contained (Comparative Example 1), or only one (specifically, PY-74) is contained (Comparative Example 2), and it is not a non-calcined pencil lead containing both PY-74 and PR-254.

[0037] (1-4) Evaluation method

[0038] The non-calcined pencil leads of Examples 1 to 3 and Comparative Examples 1 and 2 were evaluated for light resistance and discoloration resistance. The details are as follows.

[0039] (1-4-1) Line drawing

[0040] The drawing lines to be evaluated were prepared according to the method described in 8.9(a) of JIS S 6006:2020. Specifically, on drawing paper (weight per unit area 78.3 g / m 2 ~205g / m 2, whiteness 75% or more), make each non-calcined pencil lead according to the hand coating along the left and right direction and the up and down direction repeatedly, evenly coating the paper surface with a smooth glass surface as a backing plate to make the drawing line.

[0041] (1-4-2)Light resistance

[0042] Light fastness was evaluated as follows. First, the color fastness of the lines drawn as described above using the non-calcined pencil lead was confirmed in accordance with JIS L 0841:2021, 7-3-c, third exposure method, and those with no visual discoloration were evaluated as "A", those with slight visible discoloration were evaluated as "B", and those with significant discoloration were evaluated as "C".

[0043] (1-4-3) Discoloration resistance

[0044] The color change resistance is evaluated as follows. First, the L*a*b* value is measured using a colorimeter (SC-P, Suga Test Instruments Co., Ltd.) for the line drawn as described above by the non-calcined pencil lead just after manufacture. Next, the test paper with the drawn line is stored in a dark place at a temperature of 23°C and a humidity of 65% for one week, and the L*a*b* value is measured in the same manner. Then, for the ΔE value calculated from the L*a*b* values ​​before and after storage, if it is less than 4, it is recorded as evaluation A, and if it is 4 or more, it is recorded as evaluation B. In other words, the color change resistance item evaluates the difficulty of color change caused by the passage of time after the drawn line.

[0045] (1-5) Evaluation results

[0046] The evaluation results of light resistance and discoloration resistance of the non-calcined pencil leads of Examples 1 to 3 and Comparative Examples 1 and 2 are shown in Table 3 below.

[0047] [Table 3]

[0048]

[0049] As shown in Table 3, Examples 1 to 3 were excellent in all evaluation items and were rated A. On the other hand, the non-calcined pencil leads of Comparative Examples 1 and 2 were poor in all evaluation items and were rated B or C.

[0050] As described above, it is known that the orange-based unburned pencil lead contains both PY-74 and PR-254 as pigments, and the total content of PY-74 and PY-254 in the pigment is 50 mass % or more, thereby improving light resistance and discoloration resistance.

[0051] (2) Non-calcined pencil leads other than orange

[0052] (2-1) Raw material composition

[0053] The lightfastness, tinting strength and discoloration resistance of the unfired pencil lead containing pigments of other color systems as colorants in addition to CI pigment yellow and CI pigment red to present a color tone other than orange were verified. It should be noted that the raw material compositions of Examples 4 to 6 and Comparative Example 3 described below are as shown in Table 1 above.

[0054] (2-2) Pigment composition

[0055] The details of the pigment compositions in Table 1 in Examples 4 to 6 and Comparative Example 3 are shown in Table 4 below. All the pigments in Table 4 below are made of DCL.

[0056] [Table 4]

[0057]

[0058] (2-3) Manufacturing method

[0059] Based on the above composition, non-calcined pencil leads of Examples 4 to 6 and Comparative Example 3 were manufactured according to the manufacturing method mentioned in the aforementioned embodiment.

[0060] The non-calcined pencil leads of Examples 4 to 6 and Comparative Example 3 all contain pigments of other color systems in addition to CI pigment yellow and CI pigment red, and all show colors other than orange. That is, Example 4 and Comparative Example 3 show green due to PG-7, Example 5 shows light blue due to PB-15, and Example 6 shows reddish purple due to PR-122. In addition, Examples 4 to 6 contain both PY-74 and PR-254, and the total content of PY-74 and PR-254 in the pigment is 50% by mass or more. On the other hand, Comparative Example 3 contains only PY-74, and does not contain both PY-74 and PR-254.

[0061] (2-4) Evaluation method

[0062] The light resistance and discoloration resistance of the non-calcined pencil leads of Examples 4 to 6 and Comparative Example 3 were evaluated. The details are as described in (1-4) above.

[0063] (2-5) Evaluation results

[0064] The evaluation results of the light resistance and discoloration resistance of the non-calcined pencil leads of Examples 4 to 6 and Comparative Example 3 are shown in Table 5 below.

[0065] [Table 5]

[0066]

[0067] As shown in Table 5, Examples 4 to 6 were evaluated as A in all evaluation items. On the other hand, the evaluation of the discoloration resistance of the non-calcined pencil lead of Comparative Example 3 was poor, and was evaluated as B or C.

[0068] As can be seen from the above, non-calcined pencil leads other than orange series, containing both PY-74 and PR-254 as pigments, and the total content of PY-74 and PY-254 in the pigment being 50 mass % or more, also improve light resistance, coloring properties and discoloration resistance.

[0069] (3) Dark color

[0070] (3-1) Raw material composition

[0071] The change in color tone of an unburned pencil lead with a high content of pigment and a dark orange core color was measured. The raw material compositions of Examples 7 to 11 and Comparative Examples 4 to 8 described below are as shown in Table 1 above.

[0072] (3-2) Pigment composition

[0073] The details of the pigment compositions in Table 1 in Examples 7 to 11 and Comparative Examples 4 to 8 are shown in Table 6 below.

[0074] [Table 6]

[0075]

[0076] (3-3) Manufacturing method

[0077] Based on the above composition, non-calcined pencil leads of Examples 7 to 11 and Comparative Examples 4 to 8 were manufactured according to the manufacturing method mentioned in the aforementioned embodiment.

[0078] Examples 7 to 11 contain both PY-74 and PR-254, and the total content of PY-74 and PR-254 in the pigment is 50% by mass or more, which is 100% by mass. On the other hand, Comparative Examples 4 to 8 are obtained by replacing PR-254 in Examples 7 to 11 with PR-170 at the same content. Thus, Comparative Examples 4 to 8 are non-calcined pencil leads containing only PY-74.

[0079] (3-4) Color measurement method

[0080] The non-fired pencil leads of Examples 7 to 11 and Comparative Examples 4 to 8 were evaluated for their resistance to discoloration. Specifically, the L*a*b* value and L*C*H* value were measured using a colorimeter (SC-P, Suga Test Instruments Co., Ltd.) for the lines drawn as described above using the non-fired pencil leads immediately after production. Next, the test paper on which the lines were drawn was stored in a dark place at a temperature of 23°C and a humidity of 65% for one week, and the L*a*b* value and L*C*H* value were measured in the same manner. Then, the ΔE value was calculated from the L*a*b* values ​​before and after storage, and the ΔH value was calculated from the L*C*H* values ​​before and after storage.

[0081] (3-5) Results

[0082] The color measurement results of the non-calcined pencil leads of Examples 7 to 11 and Comparative Examples 4 to 8 are shown in the following Table 7. In addition, the L* value, a* value, b* value, C* value, and H* value in the following table only show the values ​​measured before storage.

[0083] [Table 7]

[0084]

[0085] As shown in Table 7, all Examples had lower ΔE and ΔH values ​​than all Comparative Examples. Therefore, it is known that a dark orange-colored non-calcined pencil lead containing both PY-74 and PY-254, where the total content of PY-74 and PY-254 in the pigment is 50% by mass or more, is less likely to discolor over time.

[0086] (4) When the color is medium

[0087] (4-1) Raw material composition

[0088] The change in color tone of an unburned pencil lead having a medium-depth orange color and a pigment content of 1 / 4 of that in (3) above was measured. It should be noted that in the raw material compositions of Examples 12 to 16 and Comparative Examples 13 to 17 described below, the content of talc was 58.5% by mass, to which 7.5% by mass of talc was added, as the pigment content in Table 1 above became 2.5% by mass.

[0089] (4-2) Pigment composition

[0090] The details of the pigment compositions in Examples 12 to 16 and Comparative Examples 9 to 13 are shown in Table 8 below.

[0091] [Table 8]

[0092]

[0093] (4-3) Manufacturing method

[0094] Based on the above composition, non-calcined pencil leads of Examples 12 to 16 and Comparative Examples 9 to 13 were manufactured according to the manufacturing method mentioned in the aforementioned embodiment.

[0095] Examples 12 to 16 contain both PY-74 and PR-254, and the total content of PY-74 and PR-254 in the pigment is 50% by mass or more, which is 100% by mass. On the other hand, Comparative Examples 9 to 13 are obtained by replacing PR-254 in Examples 12 to 16 with PR-170 at the same content. Thus, Comparative Examples 9 to 13 are non-calcined pencil leads containing only PY-74.

[0096] (4-4) Color measurement method and results

[0097] The non-calcined pencil leads of Examples 12 to 16 and Comparative Examples 9 to 13 were evaluated for discoloration resistance in the same manner as in (3-4). The results are shown in Table 9 below. It should be noted that the L* value, a* value, b* value, C* value, and H* value in the following table only show the values ​​measured before storage.

[0098] [Table 9]

[0099]

[0100] As shown in Table 9, all Examples had lower ΔE and ΔH values ​​than all Comparative Examples. Therefore, it is known that a dark orange-colored non-calcined pencil lead containing both PY-74 and PY-254, where the total content of PY-74 and PY-254 in the pigment is 50% by mass or more, is less likely to discolor over time.

[0101] (5) Light color

[0102] (5-1) Raw material composition

[0103] The change in color tone of a non-calcined pencil lead having a light orange color and a pigment content of 1 / 20 of that in (3) above was measured. It should be noted that in the raw material compositions of Examples 17 to 21 and Comparative Examples 18 to 22 described below, the content of talc was set to 60.5% by mass, with the addition of 9.5% by mass of talc, as the pigment content in Table 1 above became 0.5% by mass.

[0104] (5-2) Pigment composition

[0105] The details of the pigment compositions in Examples 17 to 21 and Comparative Examples 14 to 18 are shown in Table 10 below.

[0106] [Table 10]

[0107]

[0108] (5-3) Manufacturing method

[0109] Based on the above composition, non-calcined pencil leads of Examples 17 to 21 and Comparative Examples 14 to 18 were manufactured according to the manufacturing method mentioned in the aforementioned embodiment.

[0110] Examples 17 to 21 contain both PY-74 and PR-254, and the total content of PY-74 and PR-254 in the pigment is 50% by mass or more, which is 100% by mass. On the other hand, Comparative Examples 14 to 18 are obtained by replacing PR-254 in Examples 17 to 21 with PR-170 at the same content. Thus, Comparative Examples 14 to 18 are non-calcined pencil leads containing only PY-74.

[0111] (5-4) Color measurement method and results

[0112] The non-calcined pencil leads of Examples 17 to 21 and Comparative Examples 14 to 18 were evaluated for discoloration resistance in the same manner as in (3-4). The results are shown in Table 11 below. It should be noted that the L* value, a* value, b* value, C* value, and H* value in the following table only show the values ​​measured before storage.

[0113] [Table 11]

[0114]

[0115] As shown in Table 11, all Examples had lower ΔE and ΔH values ​​than all Comparative Examples. Therefore, it is known that a dark orange-colored non-calcined pencil lead containing both PY-74 and PY-254, where the total content of PY-74 and PY-254 in the pigment is 50% by mass or more, is less likely to discolor over time.

[0116] (6) Low brightness

[0117] (6-1) Raw material composition

[0118] The change in color tone was measured for an orange-based non-calcined pencil lead containing a small amount of pigments of other color systems as colorants in addition to CI pigment yellow and CI pigment red to reduce brightness. It should be noted that in the raw material composition of Examples 22 to 24 and Comparative Examples 23 to 25 described below, the content of talc was set to 56.5% by mass, which was added with 5.5% by mass, as the pigment content in Table 1 above became 4.5% by mass.

[0119] (6-2) Pigment composition

[0120] The details of the pigment compositions in Examples 22 to 24 and Comparative Examples 19 to 21 are shown in Table 12 below.

[0121] [Table 12]

[0122]

[0123] (6-3) Manufacturing method

[0124] Based on the above composition, non-calcined pencil leads of Examples 22 to 24 and Comparative Examples 19 to 21 were manufactured according to the manufacturing method mentioned in the aforementioned embodiment.

[0125] Examples 22 to 24 contain both PY-74 and PR-254, and the total content of PY-74 and PR-254 in the pigment is 50% by mass or more, which is 88.9% by mass. On the other hand, Comparative Examples 19 to 21 are obtained by replacing PR-254 in Examples 22 to 24 with PR-170 at the same content. Thus, Comparative Examples 19 to 21 are non-calcined pencil leads containing only PY-74.

[0126] (6-4) Color measurement method and results

[0127] The non-calcined pencil leads of Examples 22 to 24 and Comparative Examples 19 to 21 were evaluated for discoloration resistance in the same manner as in (3-4). The results are shown in Table 13 below. It should be noted that the L* value, a* value, b* value, C* value, and H* value in the following table only show the values ​​measured before storage.

[0128] [Table 13]

[0129]

[0130] As shown in Table 13, all Examples showed lower ΔE and ΔH values ​​than all Comparative Examples. Therefore, it is known that unburned pencil leads of orange color with low brightness contain both PY-74 and PY-254, and the total content of PY-74 and PY-254 in the pigment is 50 mass % or more, so that discoloration over time is less likely to occur.

[0131] (7) Verification of PR-254 content

[0132] (7-1) Raw material composition

[0133] The effect of the PR-254 content in the CI Pigment Red pigment was verified by measuring the change in color tone as described below. It should be noted that the raw material compositions of Examples 25 to 27 and Comparative Examples 22 and 23 described below are as shown in Table 1 above.

[0134] (7-2) Pigment composition

[0135] The details of the pigment compositions in Examples 25 to 27 and Comparative Examples 22 and 23 are shown in Table 14 below.

[0136] [Table 14]

[0137]

[0138] (7-3) Manufacturing method

[0139] Based on the above composition, non-calcined pencil leads of Examples 25 to 27 and Comparative Examples 22 and 23 were manufactured according to the manufacturing method mentioned in the aforementioned embodiment.

[0140] The content of PR-254 in the red pigments of Examples 25 to 27 was 50% by mass or more. On the other hand, the content of PR-254 in the red pigments of Comparative Examples 22 and 23 was less than 50% by mass.

[0141] (7-4) Color measurement method and results

[0142] The non-calcined pencil leads of Examples 25 to 27 and Comparative Examples 22 and 23 were evaluated for discoloration resistance in the same manner as in (3-4). The results are shown in Table 15 below. It should be noted that the L* value, a* value, b* value, C* value, and H* value in the following table only show the values ​​measured before storage.

[0143] [Table 15]

[0144]

[0145] As shown in Table 15, all Examples had lower ΔE and ΔH values ​​than all Comparative Examples. This shows that the PR-254 content in the red pigment is 50% by mass or more, which makes it difficult to discolor over time.

[0146] (8) Verification of the total content of PY-74 and PR-254

[0147] (8-1) Raw material composition

[0148] The effect of the total content of PY-74 and PR-254 in the total content was verified by measuring the change in color tone as described below. It should be noted that the raw material compositions of Examples 8, 28 and 29 and Comparative Examples 5, 24 and 25 described below are as shown in Table 1. Here, Example 8 and Comparative Example 5 are the same as those mentioned in (3) above.

[0149] (8-2) Pigment composition

[0150] The details of the pigment compositions in Examples 8, 28 and 29 and Comparative Examples 5, 24 and 25 are shown in Table 16 below.

[0151] [Table 16]

[0152]

[0153] (8-3) Manufacturing method

[0154] Based on the above composition, non-calcined pencil leads of Examples 8, 28 and 29 and Comparative Examples 5, 24 and 25 were manufactured according to the manufacturing method mentioned in the aforementioned embodiment.

[0155] Examples 8, 28, and 29 contain both PY-74 and PR-254, and the total content of PY-74 and PR-254 in the pigment is 50% by mass or more. Comparative Example 5 contains PY-74 but does not contain PR-254. Comparative Examples 24 and 25 contain both PY-74 and PR-254, but the total content of PY-74 and PR-254 in the pigment is less than 50% by mass.

[0156] (8-4) Color measurement method and results

[0157] The non-calcined pencil leads of Examples 8, 28 and 29 and Comparative Examples 5, 24 and 25 were evaluated for discoloration resistance in the same manner as in (3-4). The results are shown in Table 13 below. It should be noted that the L* value, a* value, b* value, C* value and H* value in the following table only show the values ​​measured before storage.

[0158] [Table 17]

[0159]

[0160] As shown in Table 17, all Examples had lower ΔE and ΔH values ​​than all Comparative Examples. Therefore, it can be seen that when both PY-74 and PR-254 are contained, the total content of PY-74 and PY-254 in the pigment is 50% by mass or more, and thus discoloration over time is less likely to occur.

[0161] Industrial Applicability

[0162] The invention can be used as a non-calcined pencil lead.

Claims

1. A non-calcined pencil lead comprising: a colorant including a pigment, a wax, a body material and a water-soluble resin, The pigments include CI Pigment Yellow 74, namely PY-74, and CI Pigment Red 254, namely PR-254. The total amount of the PY-74 and the PR-254 in the pigment is 50% by mass or more.

2. The non-calcined pencil lead according to claim 1, wherein: In the CI pigment red pigment among the above pigments, the ratio of PR-254 is 50% by mass or more.

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