JP2002226761A - Production method for nonbaked color pencil lead - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method capable of producing a metallic nonbaked color pencil lead having sufficient strengths and giving written lines with gloss and distinctness. SOLUTION: In this method for producing a nonbaked color pencil lead, at least a binder and a flaky aluminum powder are compounded and molded, the flaky aluminum powder having an aspect ratio (mean particle size/mean thickness) of 10-40 and an average thickness of 0.6-3.5 μm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a colored pencil lead obtained by blending at least a binder and a scale-like aluminum powder, kneading the mixture, and molding without firing. The present invention relates to a method for producing a colored pencil lead having a metallic luster and vividness while having handwriting.

[0002]

2. Description of the Related Art Conventionally, non-fired colored pencil leads are generally made of a binder,
3 bottles of extender such as talc and calcium carbonate, waxes such as carnauba and paraffin, lubricants composed of aliphatic metal salts such as calcium stearate, coloring materials such as various inorganic and organic pigments, plasticizers and organic solvents It is obtained by kneading with a roll mill or the like, forming into a core shape by an extruder or the like, and performing a drying treatment as necessary. Also,
As a method for producing a non-baked colored pencil lead, a wet production method and a dry production method are generally known. The wet process uses water, a plasticizer or a thermoplastic resin that is soluble in an organic solvent as a binder, and is mixed with other ingredients using a stirrer or the like under a solvent, while adjusting the amount of the solvent to be volatilized. After kneading with a three-roll mill and dispersing uniformly, the mixture is molded to a desired core diameter using an extruder or the like in the presence of these solvents, and the solvent remaining in the cores is completely removed by a drying treatment. It is a manufacturing method to remove. The dry manufacturing method is a manufacturing method in which a thermoplastic resin is heated and melted together with another compound without using a solvent, kneaded, and then extruded to obtain a finished product.

[0003] In producing these unfired colored pencil leads, metal powder such as aluminum or bronze is used as a coloring material, and various inorganic or organic pigments are added as necessary to adjust the color. Accordingly, there has been proposed a method for producing a colored pencil lead whose handwriting has a metallic luster such as gold or silver. For example, Japanese Patent Publication No. 34-137
Japanese Patent Application Publication No. 55-29554 describes a method for producing a visually colored gold pencil lead by combining an aluminum powder and a yellow pigment.
A method is described in which an emulsified polyethylene having a softening point of 110 ° C. or less is mixed with a flaky metal powder such as aluminum and a heat-resistant pigment.

[0004]

By the way, the quality characteristics of a colored pencil lead whose handwriting has a metallic luster are as follows.
The strength of the core, the glossiness of the handwriting, and the vividness of the handwriting are required. However, the color pencil core obtained by the above-mentioned conventionally known technique does not satisfy all the quality characteristics of the strength of the core body, the glossiness of the handwriting, and the vividness of the handwriting. This is a problem that, when a colored pencil lead is manufactured by a general manufacturing method including the above method, the aluminum powder is deformed or broken during the manufacturing process, whereby the quality characteristics of the colored pencil lead are significantly reduced. This is because it has occurred.

In view of the above problems, the present inventor has satisfactorily satisfied the strength of the core, the glossiness of the handwriting, and the quality characteristics of the vividness of the handwriting in a colored pencil lead that can obtain a metallic handwriting using aluminum powder. As a result of intensive research and development aimed at providing a method for manufacturing a colored pencil lead, which aims at suppressing deformation and breakage of the aluminum powder, the aspect ratio (average particle diameter) of the aluminum powder used for the colored pencil lead was determined. (Average thickness) and the average thickness were controlled to suppress the deformation and breakage of the aluminum powder, and the present invention was achieved by obtaining a completely new finding that the above-mentioned quality characteristics can be simultaneously improved.

[0006]

That is, the present invention relates to a method for producing a non-fired colored pencil lead formed by blending at least a binder and scale-like aluminum powder, wherein the scale-like aluminum powder has an aspect ratio ( (Average particle diameter / average thickness) is 10 to 40, and the average thickness is 0.6 to
A gist of the present invention is a method for producing a non-fired colored pencil lead, characterized by using at least 3.5 μm aluminum powder.

The details will be described below. The aluminum powder used in the present invention is used to make the handwriting metallic, the shape is scale-like, the aspect ratio (average particle diameter / average thickness) is 10 to 40, Further, the average thickness needs to be 0.6 to 3.5 μm. This is because, when the aspect ratio is less than 10, the aluminum powder is less deformed and broken, but the strength of the core and the glossiness of the handwriting are greatly reduced.
If it exceeds 0, the deformation and breakage of the aluminum powder increases, which causes a problem that the overall quality characteristics are significantly reduced. In addition, when the average thickness is less than 0.6 μm, the deformation and breakage of the aluminum powder increases, causing a problem that the overall quality characteristics are remarkably deteriorated. This is because the powder has little deformation and breakage, but causes a problem that the strength of the core body and the glossiness of the handwriting are greatly reduced.
The amount of the aluminum powder used is preferably about 5 to 50% by weight based on the total amount of the colored pencil lead composition. 5
When the content is less than 50% by weight, the glossiness of the handwriting is small and 50% by weight.
If it exceeds 3, the core body becomes brittle, the strength is reduced, and the vividness of the handwriting is also lost. Further, it is preferable to use aluminum powder in which the thickness of the end portion with respect to the thickness of the center portion of the aluminum powder (thickness of the end portion / thickness of the center portion) is 1 to 0.3. More preferably, the thickness of the end portion with respect to the thickness of the center portion is closer to 1. This means that the thickness of the end portion is 0.3
If it is smaller, even if the aspect ratio and the average thickness are preferable, the thin end portion is easily deformed and broken locally, and as a result, the overall quality characteristics of the color pencil core deteriorates. This is because a problem occurs.

In the present invention, the aspect ratio (average particle diameter / average thickness) and the average thickness used as characteristics indicating the shape of the aluminum powder are calculated by the following methods. Average particle diameter: The median diameter measured by a laser diffraction particle size analyzer was used. Average thickness: Calculated by the following equation 1.

[0009]

(Equation 1)

Here, the density of the aluminum powder was set to 2.5, and the hiding power was determined by measuring the area covered by 1 g of the aluminum powder at the maximum in terms of the water surface diffusion area. Further, the thickness of the end portion with respect to the thickness of the center portion of the aluminum powder (thickness of the end portion / thickness of the center portion) is the thickness of the center portion of each of the 20 aluminum particles arbitrarily selected and viewed from any direction. And the thickness of the end portion were measured, the thickness of the end portion was calculated with respect to the thickness of the center portion for each aluminum particle, and the average was calculated. Incidentally, the thickness of the center part and the thickness of the end part were measured by observing aluminum particles with a scanning electron microscope.

The scaly aluminum powder used in the present invention is used in combination with an aluminum powder obtained by a stamping method in which an aluminum piece is pulverized with a lubricating agent such as stearic acid by a stamp mill or an aluminum powder obtained by a spraying method in a drum. It is obtained by a ball mill method in which a material and an appropriate liquid are charged together with a hard sphere, ground and polished. This aluminum powder
It is needless to say that a powder that does not contain a high-boiling point solvent (such as mineral spirits) can be used, but in consideration of safety and easy handling, a paste containing a high-boiling point solvent was used. Aluminum paste can be used as well.

As an example of the flaky aluminum powder used in the present invention, TCR3010 (average particle diameter 31 μm) is used.
m, average thickness 2.7 μm, aspect ratio 11), TCR
3030 (average particle diameter 21 μm, average thickness 1.2 μm,
Aspect ratio 18), TCR3040 (average particle size 1)
6.7 μm, average thickness 0.8 μm, aspect ratio 2
1), MG1300 (average particle diameter 44 μm, average thickness 2.0 μm, aspect ratio 22), MG1000 (average particle diameter 30 μm, average thickness 0.9 μm, aspect ratio 3)
3), 54-497 (average particle diameter 51 μm, average thickness 2.3 μm, aspect ratio 22), 7410NS (average particle diameter 29 μm, average thickness 0.8 μm, aspect ratio 3)
6), 54-452 (average particle diameter 34 μm, average thickness 1.0 μm, aspect ratio 34), 1900 M (average particle diameter 28 μm, average thickness 0.8 μm, aspect ratio 3)
5) and the like (these are manufactured by Toyo Aluminum Co., Ltd.). These can be used alone or in combination of two or more. In the present invention, it is preferable to use only the aluminum powder having an appropriate aspect ratio and average thickness as described above, alone or in combination, but it is also possible to use other aluminum powder in combination. For example, it is conceivable that aluminum powder is not used for obtaining the glossiness of the handwriting, but is used for enhancing the concealment of the handwriting or as a kind of gray colorant. In such a case, generally, particles having a very small particle diameter and thickness are used, and these aluminum powders and the aluminum powder according to the present invention are used in combination to adjust the glossiness and color of the handwriting. This is also an effective method.

Examples of the binder used in the present invention include cellulose derivatives such as carboxymethylcellulose, nitrocellulose, cellulose acetate and cellulose nitrate, polymethyl methacrylate, polyvinyl alcohol, polyvinyl butyral, polyethylene, epoxy resin, polyvinyl chloride, and the like. There are synthetic resins such as vinyl chloride-vinyl acetate copolymer, polystyrene, acrylonitrile-styrene copolymer, acrylonitrile-butadiene-styrene copolymer, tragacanth rubber, gum arabic, and guar gum, and natural resins. These can be used in combination.

In the method of producing a non-fired color pencil lead of the present invention, the essential point is to use the above-mentioned essential components, and the step of forming the above-mentioned essential components into a non-fired color pencil lead may be a conventionally known step. . For example, the above essential components are blended and kneaded with a three-roll mill or a Hensyl mixer,
A method may be employed in which after forming into a core by an extruder or the like, a drying treatment is performed as necessary.

The non-fired color pencil lead obtained by the method for producing a non-fired color pencil lead of the present invention can use various additives in addition to the above essential components. For example, fatty acid amide has a property that it is easily peeled off from the core due to the frictional force between the core and the paper surface, and is an excellent wear material to promote the wear of aluminum powder and organic pigments. Furthermore, since fatty acid amide is a plate-shaped crystal and has high cleavage properties, it has an effect of lowering the viscosity of the material in the process of manufacturing a colored pencil core, such as stirring, kneading, and extrusion molding, thereby causing shearing force applied to the aluminum powder and the like. Can be reduced. Therefore, by using a fatty acid amide in the present invention, wear can be promoted, deformation and breakage of the aluminum powder can be further reduced, and a core having excellent glossiness and vividness of the handwriting can be obtained. The amount of the fatty acid amide to be used is preferably about 5 to 40% by weight based on the total amount of the colored pencil lead composition. When the content is less than 5% by weight, the effect of reducing the stress applied to the aluminum powder is small. When the content is more than 40% by weight, the amount of the aluminum powder and the coloring material is relatively reduced. This is because it may cause a decrease. Examples of fatty acid amides include lauric amide, stearic amide, erucamide, oleic amide, Nε-lauroyl lysine, lauroyl-β-alanine, myristoyl-β-alanine, palmistol-β-alanine,
Lithium lauroyl-β-alanine, myristoyl-β
Lithium alanine, sodium lauroyl-β-alanine, sodium myristoyl-β-alanine, potassium lauroyl-β-alanine, magnesium lauroyl-β-alanine, magnesium myristoyl-β-alanine, magnesium lauroyl-β-alanine alanine,
Myristoyl-β-alanine calcium, palmistol-β-alanine calcium, and the like.

Further, it is preferable to use an aluminum soap. When aluminum soap is used in combination with aluminum powder, a phenomenon has been observed in which abrasion is greatly improved and glossiness of handwriting is remarkably improved. Also, the aluminum powder is not deformed or broken during the manufacturing process of the colored pencil lead. The amount of the aluminum soap used is preferably about 3 to 40% by weight based on the total amount of the composition of the colored pencil lead. When the amount is less than 3% by weight, the improvement in abrasion is small, and when it exceeds 40% by weight, the core becomes soft,
This is because the strength is reduced. Examples of the aluminum soap include aluminum stearate, aluminum palmitate, and aluminum oleate.

If necessary, known dyes and pigments, whether inorganic or organic, may be used alone or in combination as a coloring material used for toning. Specific examples thereof include rhodamine B base (C.I. 45170B) and Soldan Red 3R (C.I.
I. 21260), methyl violet 2B base (CI. 42535B), Victoria Blue F4R
(CI. 42563B), Nigrosine base LK
(CI. 50415), Bali Fast Yellow # 3
104 (CI. 13900A), Bali Fast Yellow # 3105 (CI. 18690), Orient
Spirit Black AB (CI. 50415), Bali First Black # 3804 (CI. 1219)
5), Bali Fast Yellow # 1109, Bali Fast Orange # 2210, Bali Fast Red # 13
20, Balifast Blue # 1605, Balifast Violet # 1701, Spiron Black GMH
Special, Spiron Yellow C-2GH, Spiron Red C-GH, Spiron Red C-BH, Spiron Blue BPNH, Spiron Blue C-RH, Spiron Violet C-RH, S.P. P. T. Orange 6, S.I. P.
T. Oil-based dyes such as Blue-111, Japananol Fast Black D Conc (CI Direct Black 1
7), Water Black 100L (19), Water Black L-200 (19), Water Black # 7 (19), Kayaset Black W9 (1)
9), Direct Fast Black B (22), Direct Fast Black AB (32), Direct Deep Black EX (38), Direct Deep Black (38 similar products), Direct Fast Black Conch (51), Kaya Rath Sprague VGN (7
1), Kayak Direct Brilliant Yellow G (C.I.
I. Direct Yellow 4) Direct Fast Yellow 5
GL (26), Aizen Brimura Yellow GCLH (44), Direct Fast Yellow R (50), Aizen Direct Fast Red FH (CI Direct Red 1), Nippon Fast Scarlet GSX
(4), Direct Fast Scarlet 4BS (23), Eisen Direct Durin BH (31),
Direct Scarlet B (37), Kayak Direct Scarlet 3B (39), Aizen Murabin Conch 2BLH (75), Sumilight Red F3B
(80), Eisen Burimura Red 4BH (81)
Kayalas Sprarubin BL (83), Kayalas Light Red F5G (225), Kayalas Light Red F5
B (226), Kayasu Light Rose FR (22)
7) Direct Sky Blue 6B (CI Direct Blue 1), Direct Sky Blue 5B (15),
Benzo Brilliant Sky Blue 8GS (41), Sumilite Supra Blue BRR Conc (71), Diebogen Turquoise Blue S (86), Water Blue # 3 (86), Kayara Star Coy Blue GL (86), Direct dyes such as Daiwa Blue 215H (87), Kayalas Supra Blue FF2GL (106), Kayaras Supra Blue FFRL (108), Kayaras Splatter Turquoise Blue FBL (199) and Acid Blue Black 10B (C.I. I. Acid Black 1),
Nigrosine (2), Water Black R455 (2), Water Black R510 (2), Suminol Milling Black 8BX (24), Kayanol Milling Black VLG (26), Kayanol Milling Black BR Conc (2) 31), Mitsui Nylon Black GL (52), Eisen Opal Black WH Extra Conch (52), Sumilan Black WA (5)
2), Ranyl Black BG Extra Conc (10
7), Kayanol Milling Black TLB (10
9), Suminol Milling Black B (109), Kayanol Milling Black TLR (110), Aizen Opal Black New Conc (119), Water Black 187-L (154) Acid Yellow # 10 (CI) Acid Yellow 1), Kayak Acid Brilliant Flavin FF (7: 1), Kayasil Yellow GG (17), Xylene Light Yellow 2G 140%
(17), Suminol Leveling Yellow NR (1)
9), Water Yellow # 1 (23), Daiwa Torazine (25), Kayaktor Trazine (23),
Suminol Fast Yellow R (25) Diacid Light Yellow 2GP (29), Suminol Milling Yellow O (38), Suminol Milling Yellow MR (4)
2), Water Yellow # 6 (42), Kayanol Yellow NFG (49), Suminol Milling Yellow 3
G (72), Suminol Fast Yellow G (6)
1), Suminol Milling Yellow G (78), Kayanol Yellow N5G (110), Suminol Milling Yellow 4G 200% (141), Kayanol Yellow NG
(135), Kayanol Milling Yellow 5GW (1
27), Kayano Lumiling Yellow 6GW (14
2), Sumitomo Fast Scarlet A (CI Acid Red 8), Kayak Silk Scarlet (9),
Solar Rubin Extra (14), Daiwa New Koksin (18), Water Scarlet (1)
8), Daiwa Red No. 102 (18), Eisenbon Saw RH (26), Daiwa Red 2 (27), Suminol Leveling Brilliant Red S3B (35),
Kayasil rubinol 3GS (37), Aizen erythrosine (51), kayak acid rhodamine FB (52), Daiwa red No. 106 (52), Suminol leveling rubinol 3GP (57), Diacid alizarin rubi Nord F3G 200% (82), Alizarin Rubinol 5G (83), Eizen Eosin GH
(87), Water Red # 2 (87), Daiwa Red 103WB (87), Water Pink # 2 (92), Eisen Acid Phloxine PB (92),
Daiwa Red No. 104 (92), Rose Bengal (9)
4), Kayanol milling scarlet FGW (11
1), Kayanol Milling Rubin 3BW (129)
Suminol Milling Brilliant Red 3BN Conc (131), Suminol Milling Brilliant Red BS (138), Aizen Opal Pink BH (1)
86), Suminol Brilliant Red B Conch (2
49), Kayak Acid Brilliant Red 3BL (254), Kayak Acid Brilliant Red BL (265), Kayanol Milling Red GW (27)
6), Mitsui Acid Violet 6BN (CI Acid Violet 15), Mitsui Acid Violet BN (17), Water Violet # 1 (4)
9), Water Violet # 5 (49), Daiwa Purple No. 1 (49), Ink Violet L10 (4)
9), Sumitomo Patent Pure Blue VX (CI Acid Blue 1), Water Blue # 106 (1), Patent Blue AF (7), Water Blue # 9 (9), Daiwa Blue 1 ( 9), Ink Blue L20 (9), Spranol Blue B (15), Water Blue # 116 (15), Orient Soluble Blue OBC (22), Orient Soluble-
OBX (22), Sumino-le leveling blue 4GL
(23), Mitsui Nylon Fast Blue G (2)
5), Kayasil Blue AGG (40), Kayasil Blue BR (41), Mitsui Alizarin Safirol SE
(43), Suminol Leveling Sky Blue R Extra Conc (62), Mitsui Nylon Fast Sky Blue R (78), Sumitomobrilliant Indocyanine 6Bh / e (83), Sandrancyanin N-
6B350% (90), Water Blue # 115
(90), Water Blue # 105 (90), Orient Soluble Blue OBB (93), Spranol Cyanine 7BF (100), Sumitomobrilliant Blue 5G (103), Acid Blue (10)
3), Asilane brilliant blue FFR (10
4), Kayanol Milling Ultra Sky SE (11
2), Kayanol milling cyanine 5R (113);
Aizen Opal Cyanine 2GLH (158), Daiwa Guinea Green B (CI Acid Green 3) Acid Brilliant Milling Green (9), Daiwa Green # 70 (16), Kayanol Cyanine Green G (25) ), Suminol Milling Green G (2
7), acid dyes such as water orange # 17 (CI acid orange 56), water yellow # 2
(CI Food Ero-3), Food Yellow No. 5 (C.I.
I. Food Yellow 3) Food Red No. 3 (CI Food Red 14), Food Blue 2 (CI Acid Blue 74), Food Green 2 (CI Acid Green 5), etc. Food dye, malachite green (CI.4
2000), Victoria Blue FB (CI. 4404)
5), methyl violet FN (C.I.
5), basic dyes such as rhodamine F4G (CI. 45160) and rhodamine 6GCP (CI. 45160).

As the pigment, conventionally known pigments can be used.
As specific examples, SpecialBlack 6 and S
170, S610, 5, 5, 4, 4A, 550,
35, 250, 100, Printex 150
T, U, V, 140U, 140V, 95, 90, 85, 80, 75, 55, 45, 45, P, XE2, L6, L, 300 30, 30, 35, 25, 200, A, G (all manufactured by Degussa Japan KK), # 2400B, # 235
0, # 2300, # 2200B, # 1000, # 95
0, # 900, # 850, # MCF88, MA600,
MA100, MA7, MA11, # 50, # 52, # 4
5, # 44, # 40, # 33, # 32, # 30, CF
9, # 20B, # 4000B (Mitsubishi Chemical Industries, Ltd.), MONARCH 1300, 1100,
1000, 900, 880, 800, 70
0, MOGULL, REGAL 400R, 660
R, 500R, 330R, 300R, 99R,
ELFTEX 8, 12 and BLACK PEARLS
2000 (above, USA, Cabot Co. LTD
Manufactured), Raven7000, 5750, 5250,
5000, 3500, 2000, 1500, 1255, 1250, 1200, 1170, 1
060, 1040, 1035, 1020, 10
00, 890H, 890, 850, 790, 780, 760, 500, 450, 430, 420, 410, 22, 16, 16, and 825
Oil Beads, H20, C, Conduc
carbon blacks such as tex 975, 900, and SC (all manufactured by Colombian Carbon Japan Co., Ltd.);
KA-10, 10P, 15, 15, 20, 30, 3
5, 60, 80, 90, KR-310, 38
0, 460, 480 (Titanium Industry Co., Ltd.
Titanium oxide such as P25 (manufactured by Nippon Aerosil Co., Ltd.), inorganic pigments such as black iron oxide, yellow iron oxide, red iron oxide, ultramarine, navy blue, cobalt blue, chrome green, chromium oxide, etc .; 10G, 5G, 3G, 4, GR and A
G, para brown, permanent red 4R, fire red, brilliant carmine BS, pyrazolone red, lake red C, quinacridone red, brilliant carmine 6B, bordeaux 5B, thioindigo red,
Organic pigments such as Fast Violet B, Dioxane Violet, Alkaline Blue Lake, Phthalocyanine Blue, Indigo, Acid Green Lake, and Phthalocyanine Green. In addition, inorganic fluorescent pigments such as zinc sulfide, zinc silicate, zinc cadmium sulfate, calcium sulfide, strontium sulfide, calcium tungstate, and other known organic fluorescent pigments may be used. These colorants can be used alone or in combination with others. Further, a processed pigment in which a resin is attached around the pigment can also be used. Examples of the processed pigment include MICROLITHA, MICROLITH K,
MICROLITH T, MICROLITHWA, M
ICROLITH AB (above, CIBA-GEIGY
(Switzerland).

As other materials, those conventionally added to a color pencil lead can be used without any particular limitation.
By way of example, talc, calcium carbonate, calcium carbonate containing mica, magnesium phosphate, barium sulfate, mica, bentonite, kaolin clay, boron nitride, fluorinated graphite, etc., potassium titanate whiskers, calcium carbonate whiskers, and carbon dioxide Fibrous reinforcing materials such as titanium whisker, aluminum borate whisker, magnesium sulfate whisker, calcium sulfate whisker, paraffin wax, vaseline, microcrystalline wax, Cadillara wax, carnauba wax, caster wax, montan wax, polyethylene wax, distearyl ketone , Ketone wax, waxes such as beeswax and wood wax, oils such as lard, hardened tallow oil, hardened fish oil, and higher fatty acids such as stearic acid and metallic stearic acid. Salts can be mentioned, as the plasticizer, tricresyl phosphate, dimethyl phthalate, diallyl phthalate, dibutyl phthalate, dioctyl phthalate and propylene carbonate. Further, other compounding agents include liquid oils such as liquid paraffin, spindle oil and machine oil, and solvents such as methyl ethyl ketone, acetone, methyl isobutyl ketone and water.

[0020]

[Action] Aluminum powder has a scale-like shape and generally has a small thickness and a large particle size compared to other core compounding materials. Therefore, mechanical shear during stirring and kneading of materials, pressure during extrusion molding. The particles are liable to be deformed or broken by various forces such as shrinkage of the core due to drying and drying. When a colored pencil lead is manufactured using such aluminum powder, the glossiness of the originally obtained aluminum powder is largely lost. However, by controlling the aspect ratio (average particle diameter / average thickness) and average thickness of the aluminum powder, the non-baked color pencil lead of the present invention has found a shape that is not easily deformed or broken even after the color pencil lead manufacturing process. We were able to. This makes it possible to obtain a colored pencil lead that maintains the scale-like shape of the aluminum powder, has excellent core strength, and has excellent glossiness and vividness on paper when writing.

[0021]

【Example】 The above materials were kneaded with a three-roll mill while controlling the amount of solvent, extruded into a thin line, dried at 80 ° C. for about 8 hours in a drier to remove the solvent, and a metallic blue core having a diameter of 1.3 mm was obtained. I got

<Examples 2 to 6> In Example 1, a metallic blue core was obtained in the same manner as in Example 1 except that aluminum powder having the following shapes was used as the aluminum powder. Example 2: Aluminum powder (average particle diameter 30 μm, aspect ratio 10, average thickness 3.0 μm, edge thickness 0.6 with respect to center thickness) Example 3: Aluminum powder (average particle diameter 30 μm, aspect ratio 30) Example 4: Aluminum powder (average particle diameter: 23 μm, aspect ratio: 38, average thickness: 0.6 μm, thickness of edge relative to thickness of center) Example 5: Aluminum powder (average particle diameter: 30 μm, aspect ratio: 15, average thickness: 2.0 μm, thickness of end part to thickness of center part: 0.4) Example 6: Aluminum powder (average particle diameter) 30 μm, aspect ratio 15, average thickness 2.0 μm, end thickness 0.2 with respect to center thickness)

<Example 7> [0023] The procedure of Example 1 was repeated except that 35 parts by weight of Nε-lauroyl lysine (fatty acid amide) was used instead of 35 parts by weight of calcium carbonate (building material). A metallic blue core was obtained.

Example 8 In Example 1, 35 parts by weight of Nε-lauroyl lysine (fatty acid amide) and 5 parts by weight of aluminum stearate (aluminum soap) were mixed with N
A metallic blue core was obtained in the same manner as in Example 1 except that 40 parts by weight of ε-lauroyl lysine (fatty acid amide) and 0 parts by weight of aluminum stearate (aluminum soap) were used.

Example 9 In Example 1, 35 parts by weight of Nε-lauroyl lysine (fatty acid amide) and 40 parts by weight of calcium carbonate (body material) were used instead of 5 parts by weight of aluminum stearate (aluminum soap). Except for the above, a metallic blue core was obtained in the same manner as in Example 1.

<Comparative Examples 1 to 6> In Example 1, aluminum powder having the following shapes was used as the aluminum powder, and all other conditions were the same as in Example 1 to obtain a metallic blue core. Comparative Example 1: Aluminum Powder (Average Particle Diameter 30 μm, Aspect Ratio 8, Average Thickness 3.6 μm, Edge Thickness 0.6 to Central Thickness) Comparative Example 2: Aluminum Powder (Average Particle Diameter 30 μm, Aspect Ratio 50) Comparative Example 3: Aluminum powder (average particle diameter: 30 μm, aspect ratio: 60, average thickness: 0.5 μm, thickness of end portion with respect to thickness of center portion) Comparative Example 4: Aluminum Powder (Average Particle Diameter: 23 μm, Aspect Ratio: 58, Average Thickness: 0.4 μm, Edge Thickness: 0.6 at Center Part) Comparative Example 5: Aluminum Powder (Average Particle Diameter) Comparative Example 6: Aluminum powder (average particle diameter 30 μm, aspect ratio 50) Average thickness 0.6 .mu.m, thickness 0.2 ends to the thickness of the center)

As described above, the bending strength (unit: MP) of the core of the non-fired colored pencil cores obtained in each of the above Examples and Comparative Examples.
a), the glossiness of the writing line (unit:%), and the saturation of the writing line (unit: none) were measured. Table 1 shows the results.

The bending strength (unit: MPa) of the core is determined by JI
S Measured according to the measuring method of S6005. The glossiness of the writing line (unit:%) was determined by using a non-fired colored pencil lead and applying a surface to Kent paper with a load of 600 g so that there was no gap as a sample piece according to JIS Z8741-1983.
The mirror gloss was measured at 60 degrees using a variable angle gloss meter VGS-300A (manufactured by Nippon Denshoku Industries Co., Ltd.). The larger the value of the gloss, the higher the metallic gloss. The chroma (unit: none) of the writing line is obtained by measuring the C value (chroma) of the sample piece used for measuring the glossiness using a spectrophotometer CM-3700d (manufactured by Minolta Co., Ltd.). It was measured. The higher the saturation, the brighter the color.

[0029]

[Table 1]

[0030]

As described above, the method for producing a non-fired colored pencil lead according to the present invention provides a metallic-colored pencil lead that has less deformation and breakage of the aluminum powder, and has excellent core strength, handwriting glossiness and vividness. A colored pencil lead can be provided.

Claims (4)

[Claims] 1. A method for producing a non-fired colored pencil lead formed by blending at least a binder and flaky aluminum powder, wherein the flaky aluminum powder has an aspect ratio (average particle diameter / average thickness) of 10%. A method for producing a non-fired colored pencil lead, characterized by using at least aluminum powder having an average thickness of 0.6 to 3.5 [mu] m. 2. An aluminum powder having a thickness at an end portion (thickness at an end portion / thickness at a center portion) with respect to a thickness at a central portion of 1 to 0.3 is used as the flaky aluminum powder. Item 4. The method for producing a non-fired colored pencil lead according to Item 1. 3. The method for producing a non-fired colored pencil lead according to claim 1, further comprising a fatty acid amide. 4. The method according to claim 1, further comprising using an aluminum soap.