A refill product comprising colored pencil leads and a refill case containing the leads.

Abstract

To provide an extra lead product which suppresses adhesion of a colored pencil lead to a case.SOLUTION: A colored pencil lead includes a colored pencil lead, and an extra lead case containing the same. The colored pencil lead contains a porous lead body containing an extender, an inorganic binder, a coloring agent, and an organic solvent capable of dissolving the coloring agent, and a hardly volatile liquid that cannot dissolve the coloring agent. In an inner surface of the extra lead case, a resin material having a solubility parameter different from the hardly volatile liquid by 1.5 or more is arranged.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a lead refill product, and more specifically to a lead refill product that includes a colored pencil lead that has excellent color development and a smooth writing feel, and a lead refill case that houses the lead. [Background technology]

[0002] Conventionally, colored pencil leads used in mechanical pencils and the like are primarily composed of a filler such as boron nitride and a binder such as clay, optionally containing organic polymer compounds, which are extruded and then baked at high temperatures to produce a white porous substrate, in which the pores are impregnated with dye-containing ink. When such colored pencil leads are used to write on paper, the ink impregnated in the pores penetrates into the paper fibers, forming a handwritten mark. In order to express a variety of colors, it is desirable to use a variety of coloring materials to achieve better color development. Furthermore, improvements are also desired in terms of erasability, stability over time, and writing feel.

[0003] Meanwhile, because colored pencil leads are consumables, refill products are also available commercially. Refill products generally consist of colored pencil leads housed in a case. The case is made of a durable, lightweight resin. Various compounds are blended into colored pencil leads to improve their performance. However, when a particular compound has a high affinity with a particular resin, the colored pencil lead can adhere to the case, making it difficult to remove the lead from the case. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2019-099633 Summary of the Invention [Problem to be solved by the invention]

[0005] To provide a refill lead product which has excellent color development in handwriting, high stability over time, and stores color pencil leads which write smoothly, and which prevents the color pencil leads from adhering to a refill lead case and allows the color pencil leads to be easily taken out. [Means for solving the problem]

[0006] The refill product according to the present invention comprises colored pencil leads and a refill case containing the leads, The colored pencil lead is Body material and an inorganic binder; A colorant; an organic solvent capable of dissolving the colorant; a porous core comprising: A hardly volatile liquid that cannot dissolve the colorant comprising On a part of the inner surface of the refill case where the colored pencil lead may come into contact, The liquid-crystal display device is characterized in that a resin material having a solubility parameter that differs from the solubility parameter of the low-volatility liquid by 1.5 or more is disposed. [Effects of the Invention]

[0007] The refill lead product according to the present invention stores colored pencil leads that can produce handwriting with excellent color development, while preventing the colored pencil leads from adhering to the inner surface of the case and allowing for easy removal and replacement. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a perspective view of a refill product according to the present invention. [Figure 2] FIG. 2 is a longitudinal cross-sectional view of a refill lead case that can be used in the present invention. [Figure 3] FIG. 2 is a cross-sectional view of a refill case that can be used in the present invention. [Figure 4] FIG. 10 is a vertical cross-sectional view of another refill lead case that can be used in the present invention. [Figure 5] FIG. 10 is a cross-sectional view of another refill case that can be used in the present invention. [Figure 6] FIG. 10 is a vertical cross-sectional view of yet another refill lead case that can be used in the present invention. [Figure 7] FIG. 10 is a cross-sectional view of yet another refill lead case that can be used in the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0009] <Refill products> The present invention relates to a lead refill product. The lead refill product is used for mechanical pencils, lead holders, and the like. It refers to a product form of a pencil lead for replacement or refilling. Because these pencil leads are usually fragile, they are distributed in a form housed in a hard case. Therefore, pencil leads are generally considered to be products housed in a case.

[0010] The refill product of the present invention also comprises colored pencil leads and a refill case that contains the leads. These will be explained below.

[0011] <Colored pencil lead> The structure of the color pencil lead used in the present invention will be described below.

[0012] The porous core used in the colored pencil lead of the present invention comprises a filler and an inorganic binder as its main components. Examples of fillers include white materials such as titanium oxide, mica, talc, boron nitride, alumina, and calcium carbonate, as well as colored materials such as molybdenum disulfide, tungsten disulfide, and graphite. It is desirable for the colored pencil lead used in the present invention to produce vivid handwriting. Furthermore, when fluorescent colorants are used as colorants to produce fluorescent handwriting, it is preferable for the filler not to inhibit color development. Therefore, to produce handwriting with high brightness, it is preferable to use a white filler. Boron nitride is particularly preferred because the filler does not inhibit color development and increases the strength of the colored pencil lead.

[0013] Examples of the inorganic binder include clays such as kaolinites, halloysites, montmorillonites, sericites, and bentonites, ceramics, zeolites, diatomaceous earth, activated clay, silica, aluminum phosphate, silicone resins, and silicone rubbers, and these can be used alone or in combination.

[0014] The blending ratio of the filler material, which is the main component of the porous core, to the inorganic binder is not particularly limited, but is preferably 9:1 to 7:3 by mass ratio.

[0015] In the present invention, the porous core is typically a combination of a colorant and a high-boiling organic solvent on a porous substrate. The colorant may be localized in a portion of the porous substrate, primarily composed of an extender or inorganic binder, or may be uniformly dispersed throughout the porous substrate. However, localization within a portion of the porous core is preferred. Specifically, the colorant is preferably attached or adsorbed within the pores of the porous substrate. The colorant may be in the form of fine particles or dissolved or dispersed in a high-boiling organic solvent, as described below. Presence of the colorant in this state in the final colored pencil lead inhibits penetration of the colorant into the paper during writing, improving color development and erasability. Here, the colorant typically forms a layer or phase within the pores. That is, it generally forms a uniform or non-uniform layer on the inner surface of the pores, or adheres in clumps. In the present invention, "pores" refers to the pores in the base material, e.g., the porous substrate, from which the organic solvent, etc., has been removed from the pencil lead. For example, in the case of a porous core, an organic solvent may penetrate into the pores, and the pores of this porous core refer to the pores after the organic solvent has been removed from the porous core.

[0016] In the present invention, the porous core comprises a filler, an inorganic binder, a colorant, and a high-boiling organic solvent. Pencil leads are generally produced by molding a mixture of the filler and binder and then firing the resulting mixture; a similar method can be applied to the present invention. Specifically, pencil leads can be produced by firing a mixture of the filler and inorganic binder, and then adsorbing or attaching a colorant and a high-boiling organic solvent to the resulting porous substrate (details will be described later). Alternatively, a filler, an inorganic binder, a colorant, and a high-boiling organic solvent may be mixed and fired. In such cases, it is preferable to use a colorant with high heat resistance or a high-boiling organic solvent with a boiling point higher than the firing temperature. On the other hand, the former method allows the use of colorants with low heat resistance or high-boiling organic solvents with a boiling point lower than the firing temperature.

[0017] Alternatively, a porous core can be produced by compressing a mixture containing a filler, an inorganic binder, an inorganic substance, a water-soluble resin, and, if necessary, a colorant at high pressure, and then immersing the mixture in water or a solvent to remove the inorganic substance, water-soluble resin, etc.

[0018] The porosity of the porous core used in the present invention is not particularly limited, but is preferably in the range of 1 to 50%, more preferably 5 to 50%, even more preferably 10 to 40%, and particularly preferably 20 to 40%. If the porosity is less than 1%, the amount of colorant and non-volatile liquid present in the pores will be reduced, tending to result in poor color development and slight resistance to writing. If the porosity is greater than 50%, the resulting porous core will tend to be weaker and more prone to breaking. A porosity in the range of 1 to 50% is preferred because it provides good color development, a smooth writing feel, and maintains the strength of the baked color pencil lead.

[0019] The porosity of the porous substrate used in the present invention can be measured by the following method, with reference to JIS R1634 (1998). First, the dry mass (W1) of the porous substrate is measured. Next, the substrate is immersed in a highly permeable liquid (e.g., benzyl alcohol) and the pores of the porous substrate are allowed to absorb the liquid until saturated, after which the immersed mass (W2) is measured. Next, the porous substrate is removed from the liquid, and the liquid adhering to its surface is removed, after which the saturated mass (W3) is measured. Using these measured values, the porosity can be calculated using the following mathematical formula (1).

[0020] Porosity = (W3-W1) / (W3-W2)×100 (1)

[0021] The porosity of colored pencil leads or porous cores can also be measured using a similar method. However, before applying the above-mentioned method for measuring the porosity of porous substrates, it is necessary to remove the organic solvent by heating or reducing the pressure. When measuring the porosity of colored pencil leads or porous cores, even after removing the solvent, some organic solvent may remain in the pores. For this reason, there may be a slight difference between the porosity of the porous substrate and the porosity of the colored pencil leads or porous cores. Taking such differences into consideration, the porosity of the porous substrate is preferably in the range of 5 to 50%, more preferably in the range of 10 to 40%, and particularly preferably in the range of 20 to 40%.

[0022] Dyes or pigments can be used as colorants. Colored pigments obtained by dyeing resins with dyes can also be used. Dyes generally have low heat resistance, but when dissolved in water, they easily penetrate porous substrates, making it easier to manufacture pencil leads.

[0023] The dyes that can be used in the present invention are not particularly limited, and include general dyes and fluorescent dyes.

[0024] Examples of general dyes include oil-soluble dyes, acid dyes, basic dyes, metal-containing dyes, etc. In addition, examples of salt-forming dyes of these dyes include salt-forming dyes of acid dyes and basic dyes, salt-forming dyes of basic dyes and organic acids, and salt-forming dyes of acid dyes and organic amines. More specifically, Balifast Black 1802, Balifast Black 1805, Balifast Black 1807, Balifast Violet 1701, Balifast Violet 1704, Balifast Violet 1705, Balifast Blue 1601, Balifast Blue 1605, Balifast Blue 1613, Balifast Blue 1621, Balifast Blue 1631, Balifast Red 1320, Balifast Red 1355, Balifast Red 1360, Balifast Yellow 1101, Balifast Yellow 1151, Nigrosine Base EXBP, Nigrosine Base EX, BASE OF BASIC DYES ROB-B, BASE OF BASIC DYES RO6G-B, BASE OF BASIC DYES VPB-B, BASE OF BASIC DYES VB-B, BASE OF BASIC DYES MVB-3 (Orient Chemical Industry Co., Ltd.), Aizen Spiron Black GMH-Special, Aizen Spiron Violet CRH, Aizen Spiron Blue GNH, Aizenspiron Blue 2BNH, Aizenspiron Blue C-RH, Aizenspiron Red C-GH, Aizenspiron Red C-PH, Aizenspiron Red C-BH, Aizenspiron Yellow C-GNH, Aizenspiron Yellow C-2GH, SPT Blue 111, SPT Blue GLSH-Special, SPT Red 533, SPT Orange 6, SBN Violet 510, SBN Yellow 530, SRC-BH (Hodogaya Chemical Co., Ltd.), etc.

[0025] Examples of fluorescent dyes include Basic Yellow 1, Basic Yellow 40, Basic Red 1, Basic Red 1:1, Basic Red 13, Basic Violet 1, Basic Violet 7, Basic Violet 10, Basic Violet 11:1, Basic Orange 22, Basic Blue 7, Basic Green 1, Acid Yellow 3, Acid Yellow 7, Acid Red 52, Acid Red 77, Acid Red 87, Acid Red 92, Acid Blue 9, Disperse Yellow 121, Disperse Yellow 82, Disperse Yellow 83, Disperse Orange 11, Disperse Red 58, Disperse Blue 7, Direct Yellow 85, Direct Orange 8, Direct Red 9, Direct Blue 22, Direct Green 6, Solvent Yellow 44, Solvent Red 49, Solvent Blue 5, and Solvent Green 7.

[0026] These dyes may be used alone or in combination of two or more to adjust the color of the writing, etc., as long as the performance of the colored pencil lead is not affected. Furthermore, these dyes may be used in combination with other dyes.

[0027] Any pigment may be used as the colorant, and ultrafine pigments, processed pigments, etc. may also be used.

[0028] It is also possible to use a color pigment obtained by dyeing a resin with a dye, etc. Such a color pigment is preferable because it can improve color development.

[0029] The resin constituting the color pigment can be any resin such as an acrylic resin, a styrene-acrylonitrile resin, a styrene resin, a nitrogen-containing resin, a polyethylene resin, or a polypropylene resin. The dye to be combined with these resins can be selected from those listed above.

[0030] Considering the solubility, dispersibility, and dispersion stability in high-boiling organic solvents, and the dyeability with dyes, etc., among these resins, nitrogen-containing resins or styrene-acrylonitrile resins are preferably used, with nitrogen-containing resins being more preferred. Among nitrogen-containing resins, melamine resins, polyamide resins, urethane resins, urea resins, and benzoquanamine resins are preferred. Furthermore, among these, melamine resins or polyamide resins are preferred, with melamine resins being more preferred, from the viewpoint of solubility stability in high-boiling organic solvents.

[0031] Examples of color pigments include the NKS-1000 series, MPI-500 series (manufactured by Nippon Fluorescent Chemical Co., Ltd.), FNP series, and FM series (manufactured by Shinroihi Co., Ltd.).

[0032] These color pigments may be used in combination of two or more kinds, for example, for the purpose of adjusting the color of handwriting, as long as the effects of the present invention are not impaired. Furthermore, these color pigments may be used in combination with dyes.

[0033] In the present invention, it is also preferable to use a fluorescent colorant. By using such a colorant, it is possible to obtain handwriting with fluorescence and more color development. This makes it easy to use not only for leaving letters but also for drawing and making marks.

[0034] The content of the colorant relative to the total mass of the colored pencil lead varies depending on the type of colorant, but is preferably 0.1 to 30 mass%, more preferably 0.2 to 25 mass%, and even more preferably 1 to 20 mass%.

[0035] When a porous core is formed by combining a colorant with a porous substrate, the porous core can be easily produced by impregnating a porous substrate containing an extender and an inorganic binder with a colorant solution prepared by dissolving the colorant in a solvent, and then removing part of the solvent as necessary (details will be described later). For this reason, it is preferable that the solvent used in the production be capable of dissolving the colorant used.

[0036] The colored pencil leads used in the present invention contain an organic solvent capable of dissolving the colorant contained in the colored pencil lead. The inclusion of this organic solvent allows the colored pencil leads used in the present invention to have excellent performance, such as color development and writing feel. As described below, the colored pencil leads are generally impregnated with an organic solvent and then heated. Therefore, it is preferable for the organic solvent to have a high boiling point so that the organic solvent does not evaporate during heating. Since the organic solvent is selected depending on the heating conditions during the manufacturing process, its boiling point is not particularly limited. However, it is preferable for the organic solvent to have a boiling point of 180°C or higher, more preferably 200°C or higher, and particularly preferably 250°C or higher. In the present invention, this solvent is conveniently referred to as a high-boiling-point organic solvent.

[0037] Here, a high-boiling organic solvent capable of dissolving a colorant means that the solubility of the colorant in the high-boiling organic solvent is 10 g / 100 g or more at 20° C., that is, 10 g or more of the colorant dissolves in 100 g of the high-boiling organic solvent at 20° C. The higher the solubility of the colorant, the higher the storage stability of the colored pencil lead tends to be; the solubility is more preferably 30 g / 100 g or more, and even more preferably 40 g / 100 g or more.

[0038] Such a solvent can be selected arbitrarily taking into consideration the solubility of the colorant used and other properties, but aromatic glycol ethers or aliphatic glycol ethers are preferred. Glycol ethers contain both an ether group and a hydroxyl group in their structure and generally have the characteristics of high solubility for dyes and resins, as well as high affinity for other organic solvents.

[0039] Specific examples of such high boiling point organic solvents include Diethylene glycol monophenyl ether (phenyl diglycol, 298°C), Diethylene glycol monobenzyl ether, (302°C), Diethylene glycol monobutyl ether (231°C), Triethylene glycol monobutyl ether (butyl triglycol, 271°C), Ethylene glycol monobenzyl ether (256°C) Triethylene glycol monomethyl ether (249°C), Phenyl cellosolve (245°C), Propylene glycol monophenyl ether (243°C) The numbers in parentheses indicate boiling points (same below).

[0040] Furthermore, as the high-boiling organic solvent, a carboxylic acid ester of a polyalkylene glycol or a carboxylic acid ester of an alcohol can be used.

[0041] Additionally, higher fatty acids and higher alcohols can also be used. Specific examples include carboxylic acids with 10 or more carbon atoms, such as decanoic acid (259°C) and oleic acid (360°C), and alcohols with 12 or more carbon atoms, such as dodecyl alcohol (259°C), myristyl alcohol (292°C), benzyl alcohol (205°C), and 3-methoxy-3-methyl-1-butanol (174°C). Care must be taken when using higher fatty acids, as they may cause corrosion when colored pencil leads are used in mechanical pencils and come into contact with metal parts.

[0042] Some organic solvents are liquid at room temperature and pressure, but when heated under normal pressure, they sublimate or undergo chemical reactions that denature them, making it impossible to accurately measure their boiling points. Even such organic solvents can be used as high-boiling organic solvents in some cases. In such cases, for example, if the weight loss rate after 30 minutes when held at 180°C under normal pressure is 10% by mass or less, the boiling point of the high-boiling organic solvent can be determined to be 180°C or higher.

[0043] The content of the high-boiling organic solvent contained in the colored pencil lead used in the present invention is adjusted appropriately depending on the purpose, but the content of the high-boiling organic solvent is preferably 0.5 to 20 mass %, and more preferably 1 to 15 mass %, based on the total mass of the colored pencil lead. The content of the high-boiling organic solvent can be measured by any method. For example, the presence of a high-boiling organic solvent in the colored pencil lead can be confirmed by methods such as thermogravimetry.

[0044] The colored pencil lead used in the present invention may contain an organic solvent other than the high-boiling organic solvent (hereinafter, sometimes referred to as a low-boiling organic solvent). The organic solvent referred to here is also different from the low-volatility liquid described below. Specifically, it is an organic solvent with a boiling point of less than 180°C that can dissolve a colorant.

[0045] Among low-boiling-point organic solvents, those with relatively high boiling points, for example, those with a boiling point of 150°C or higher but less than 180°C, are generally expected to complement the effects of high-boiling-point organic solvents, such as improving the writing feel. Furthermore, those with relatively low boiling points, for example, those with a boiling point less than 150°C, are generally effective in reducing the viscosity of the colorant solution when the colorant is impregnated into a porous substrate during the manufacturing process. However, since most or all of these relatively low-boiling-point organic solvents are removed during the manufacturing process, they are often rarely present in colored pencil leads.

[0046] Examples of such low-boiling organic solvents include: Xylene (139°C), Toluene (111°C), Isopropyl alcohol (82°C), Methyl ethyl ketone (79°C), Ethyl alcohol (78°C), Ethyl acetate (77°C), Acetone (56°C) Examples include:

[0047] The colored pencil lead used in the present invention has the pores of the porous lead body filled with a non-volatile liquid, which further improves the writing feel.

[0048] In the present invention, the term "low-volatility liquid" refers to a liquid that is incapable of dissolving a colorant and that is not likely to volatilize at room temperature. Here, "insoluble" does not mean that the solubility of the colorant is zero, but rather that the colorant is substantially insoluble. Here, the solubility of the colorant in a monovolatile liquid is preferably lower than the solubility in the high-boiling organic solvent described above. More specifically, the solubility of the colorant in a low-volatility liquid at 20°C is preferably less than 10 g / 100 g, and more preferably 5 g / 100 g or less.

[0049] In the present invention, the low-volatility liquid has a characteristic solubility parameter (hereinafter sometimes referred to as SP value). The SP value of this low-volatility liquid satisfies a specific relationship with the SP value of the resin material used in the refill case, which will be described later. This relationship will be described later, but generally, the SP value of the low-volatility liquid is preferably 6 to 8. Here, although known SP values ​​include Fedors solubility parameter, Hildebrand solubility parameter, and Hansen solubility parameter, in the present invention, the Fedors solubility parameter is used as the solubility parameter.

[0050] The boiling point of the hardly volatile liquid is not particularly limited, but it is preferable that the liquid does not volatilize at 250°C or less.

[0051] The use of such a non-volatile liquid maintains the stability of the colored pencil lead over time at a high level and improves the writing feel. Furthermore, if the lead of a replacement lead product contains an organic solvent, there is a possibility that the refill lead and the case will adhere to each other inside the case. However, by including a non-volatile liquid in the colored pencil lead, it is possible to improve this adhesion.

[0052] Furthermore, the low-volatility liquid preferably has a low viscosity in order to facilitate impregnation into the pores of the porous core.

[0053] Furthermore, the surface tension of the non-volatile liquid is preferably 35 mN / m or less, more preferably 30 mN / m or less, and even more preferably 25 mN / m or less, because this allows for excellent impregnation into the pores of the porous core and allows the non-volatile liquid to impregnate the entire porous core evenly and without unevenness, resulting in a colored pencil lead with excellent writing feel and erasability. Here, the surface tension can be measured at a temperature of 25°C using the method specified in JIS K2241.

[0054] Specific examples of preferred low-volatility liquids include those selected from the group consisting of silicone oil, fluorine-based oil, mineral oil, vegetable oil, and liquid paraffin, with silicone oil being more preferred. Silicone oil exhibits minimal viscosity change with temperature and excellent stability, making it possible to produce colored pencil leads that are less susceptible to environmental changes and the passage of time. Furthermore, when used in mechanical pencils, colored pencil leads are less likely to corrode metal components such as the tip opening, zipper, and lead holder of the mechanical pencil. Silicone oil is also preferred because it effectively prevents adhesion of colored pencil leads to the case. Silicone oil is also preferred because it can impart excellent writing feel and color development to colored pencil leads. As silicone oils, dimethyl silicone and methylphenyl silicone are particularly preferred, and modified silicones are also preferred. Furthermore, silicones that do not easily dissolve the colorants are preferred. By not easily dissolving the colorants, the colorants are prevented from penetrating into the interior of the paper along with the non-volatile liquid in the written marks, thereby improving erasability. Furthermore, liquid paraffins with a carbon number of 14 or more are preferred. Alpha-olefins can also be used as the non-volatile liquid.

[0055] The content of the low-volatility liquid relative to the total mass of the color pencil lead is preferably 5 to 40 mass %, more preferably 8 to 45 mass %, and even more preferably 10 to 35 mass %.

[0056] The colored pencil lead used in the present invention may contain various additives to the extent that they do not affect the performance of the lead. Specific additives include surfactants, preservatives, antifungal agents, resins, etc.

[0057] The shape of the colored pencil leads used in this invention is not particularly limited, but they are generally linear bodies with circular cross sections. Regarding their size, for example, for colored pencil leads for mechanical pencils, the cross-sectional diameter is preferably 0.2 to 2.0 mm, more preferably 0.3 to 0.7 mm. The length is preferably 30 to 100 mm, more preferably 40 to 70 mm. Colored pencil leads with relatively large cross-sectional diameters can also be held in a lead holder and used for writing. In such writing implements, the cross-sectional diameter of the colored pencil leads is preferably 0.5 to 6.0 mm, more preferably 0.8 to 4.0 mm, and even more preferably 0.8 to 3.0 mm. The length of the colored pencil leads used in such lead holders is not particularly limited, but is generally 8 to 200 mm.

[0058] The colored pencil leads used in the present invention can achieve high physical strength when a porous substrate produced by baking is used. This is thought to be because the colorant forms a uniform or non-uniform layer on the inner surface of the pores or adheres in clumps. The bending strength of the colored pencil leads used in the present invention is preferably 120 MPa or higher, and more preferably 180 MPa or higher. Here, bending strength can be measured using the method specified in JIS S 6005:2007.

[0059] The colored pencil leads used in the present invention can be configured to be free of acidic components. Colored pencil leads are often used in mechanical pencils and the like, and therefore often come into contact with metal materials. Therefore, by configuring them to be free of acidic components, corrosion of the metal parts of the mechanical pencil can be suppressed. Therefore, it is preferable that the colored pencil leads used in the present invention do not contain acidic materials.

[0060] <Manufacturing method of colored pencil lead> There are no particular restrictions on the method for producing the colored pencil leads used in the present invention. (a) a kneading step of kneading an extender and an inorganic binder to prepare a mixture; (b) extrusion of the mixture to form a linear product; (c) a firing step of firing the linear molding to form a porous substrate; (d) an impregnation step of contacting the porous substrate with a colorant solution containing a colorant and a high-boiling organic solvent to impregnate the porous substrate; (e) a drying step in which the porous substrate after the impregnation step is heated, for example, at a temperature lower than the boiling point of the high-boiling organic solvent to form a porous core; (f) a filling step of bringing the porous core body into contact with a hardly-volatile liquid that cannot dissolve the colorant, thereby filling the voids of the porous core body with the hardly-volatile liquid; It is preferable to produce the polymerizable compound by a method comprising the steps of: This method is described below.

[0061] (a) Mixing process First, the filler and inorganic binder are kneaded to prepare a mixture. This mixture will be the main component of the porous substrate. During mixing, organic solvents, plasticizers, etc. can be added as needed. The organic solvent used here is used to impart fluidity to the raw material mixture and to homogenize the mixture. It is almost completely removed during the firing process and is separate from the high-boiling organic solvent, low-boiling organic solvent, and refractory liquid mentioned above.

[0062] (b) Extrusion process The resulting mixture is then extruded to form a linear product. Since the colored pencil leads used in the present invention are generally preferably formed into linear bodies having a circular cross section, the linear product is formed by extrusion.

[0063] (c) Firing process The resulting linear molding is dried as needed and then fired to form a porous substrate. The firing removes the organic solvent contained in the mixture, and the filler and inorganic binder are sintered to form a porous substrate. The firing conditions are not particularly limited as long as they allow the materials to be sintered to form a porous substrate; for example, the maximum temperature can be set to 650 to 1000°C. To avoid sudden temperature changes, the firing temperature can be increased continuously or stepwise. In such cases, the temperature increase rate can be set to, for example, 10 to 100°C / hr. After the temperature is increased to a set value, firing at a constant temperature for a certain period of time, for example, 0.5 to 2 hours, is also preferred. Furthermore, these conditions can be arbitrarily combined depending on the purpose. For example, conditions that can be used include increasing the temperature from room temperature to 650°C at a rate of 10°C / hr in an oxygen atmosphere and then maintaining the temperature at 650°C for one hour, or increasing the temperature from room temperature to 1000°C at a rate of 100°C / hr and then maintaining the temperature at 1000°C for one hour.

[0064] (d) Impregnation process The porous substrate is then cooled as needed, and then contacted with a solution containing a colorant and a high-boiling organic solvent. In this process, the colorant solution penetrates into the pores present in the porous substrate. The impregnation method can be atmospheric pressure impregnation or reduced pressure or pressure impregnation.

[0065] The colorant content of the colorant solution is not particularly limited, but is preferably 5 to 50% by mass, more preferably 5 to 45% by mass, and particularly preferably 10 to 40% by mass, based on the total mass of the solution. If the colorant content is less than this range, the colorant content will be low and color development will tend to be poor. If the content is greater than this range, color development will tend not to improve in proportion to the amount of colorant added, and the colorant may precipitate over time, resulting in poor stability of the solution over time. A surfactant may also be added to the solution to improve the solubility and stability of the colorant.

[0066] Furthermore, using a mixed solvent of a high-boiling organic solvent and a low-boiling organic solvent as the solvent for the colorant solution reduces the viscosity of the colorant solution, facilitating impregnation and facilitating the formation of voids within the pores during the subsequent drying process. In this case, the pores of the core are also easily impregnated with the low-volatile organic solvent, allowing the effects of impregnating the low-volatile organic solvent to be fully achieved. As such a low-boiling organic solvent, a solvent that evaporates at 100°C or less is preferred, more preferably 90°C or less, and even more preferably 80°C or less is preferred. Aliphatic alcohols having 1 to 4 carbon atoms are more preferred. The blending ratio of the high-boiling organic solvent to the low-boiling organic solvent can be adjusted depending on the difference in boiling points and the solubility of the colorant. For example, the ratio of the mass of the high-boiling organic solvent to the mass of the low-boiling organic solvent is preferably 1:1 to 1:15, more preferably 1:1 to 1:12, even more preferably 1:1.5 to 1:10, and particularly preferably 1:1.5 to 1:7.

[0067] (e) Drying process Subsequently, the porous substrate after the impregnation step is heated to remove a portion of the solvent contained in the solution impregnated in the pores. As a result, the colorant and high-boiling organic solvent remain in the pores and are adsorbed or attached. Then, as a portion of the solvent is removed by heating and the impregnation of the solvent into the porous substrate progresses, voids are formed in the pores, forming a porous core. Drying is performed at a temperature lower than the boiling point of the high-boiling organic solvent. However, if the colorant solution contains a solvent with a relatively low boiling point, drying can be performed at a lower temperature, for example, 200°C or less, and preferably 100°C or less. Drying at a low temperature is preferable because it reduces energy costs.

[0068] (f) Filling process If necessary, the formed porous core is cooled and then contacted with a non-volatile liquid. This process fills the voids formed in the porous core with the non-volatile liquid. The conditions for this process are not particularly limited, but for example, a temperature of 60°C for 6 to 12 hours can be used. Impregnation with the non-volatile liquid can be performed by normal pressure impregnation or reduced pressure / pressure impregnation.

[0069] If necessary, further washing or the like can be carried out to obtain color pencil leads.

[0070] <Refill cases and refill products> The refill lead product according to the present invention comprises the aforementioned colored pencil leads housed in a refill lead case. Furthermore, a resin material having a solubility parameter that differs by 1.5 or more from the solubility parameter of the non-volatile liquid is disposed on a portion of the inner surface of the refill lead case that may come into contact with the pencil lead. The refill lead case is made of a relatively hard material to protect the colored pencil leads, but is generally made of resin for ease of manufacturing and cost reasons. However, if an appropriate resin is not selected, the colored pencil leads and the resin material may adhere to each other.

[0071] The inventors' research has shown that such adhesion can be suppressed when there is a sufficiently large difference between the SP value of the non-volatile liquid contained in the colored pencil lead and the SP value of the resin that makes up the lead refill case. Naturally, this adhesion occurs in the area of ​​the lead refill case that comes into contact with the colored pencil lead, so it is sufficient that the SP value of the resin disposed in that area of ​​the lead refill case is sufficiently different from the SP value of the non-volatile liquid. Specifically, the difference between the SP value of the non-volatile liquid and the SP value of the resin material disposed in the area that comes into contact with the colored pencil lead must be 1.5 or more, preferably 2.0 or more, more preferably 3.0 or more, and even more preferably 5.0 or more.

[0072] The difference between the SP value of the non-volatile liquid and the SP value of the resin material must be 1.5 or more, but either one can be larger. Furthermore, as long as these relative differences are satisfied, there are no particular limitations on the SP value of the non-volatile liquid and the SP value of the resin material. For example, if silicone oil with an SP value of 7.2 is used as the non-volatile liquid, the SP value of the resin material must be 5.7 or less or 8.7 or more. Examples of resin materials that satisfy this condition include polystyrene (8.6 to 9.7), vinyl acetate resin (9.4), vinyl chloride (9.5 to 9.7), polycarbonate (9.7), polyacetal (11.1), acrylonitrile-styrene resin (12.8), and acrylonitrile-butadiene-styrene copolymer synthetic resin (12.1 to 15.0). Generally, the SP value of a resin material tends to be higher than that of a non-volatile liquid. The SP value of a resin material is preferably 8.5 to 15.

[0073] Furthermore, it is preferable that the remaining amount of pencil lead contained in the refill product according to the present invention can be seen from the outside. For this reason, it is preferable to use a transparent resin material for the case. Therefore, it is preferable to use a resin that is highly robust, has excellent moldability, and is transparent, and it is particularly preferable to use polycarbonate (9.7) or acrylonitrile styrene resin (12.8).

[0074] In the present invention, the shape of the refill lead case is not particularly limited, and any conventionally known shape can be used. For example, a refill lead case can be used that includes a storage section for storing colored pencil leads and a lid section that temporarily seals the opening of the storage section and can be deformed to allow the colored pencil leads to be removed. Here, the lid section can be any object commonly referred to as a lid section. Specifically, during transportation or storage, the lid section temporarily seals the opening of the storage section to hold the colored pencil leads inside the refill lead case, and when necessary, can be deformed, such as by detaching, moving, or rotating, to allow the colored pencil leads to be removed from the opening of the storage section.

[0075] The simplest example is a lead refill case, as shown in Figure 1. The lead refill case is made up of a cylindrical storage section 101 with one end sealed and a lid 102 that fits into an opening formed at one end of the storage section. The colored pencil leads 103 stored in this lead refill case can be removed from the storage section by removing the lid 102 from the storage section 101. In the refill product according to the present invention, a specific resin material is disposed in a portion of the refill case that may come into contact with the colored pencil lead. In the refill case shown in Fig. 1, the entire inner surface of the space defined by the inner surface of the storage section and the bottom surface 102a of the lid after fitting becomes a portion that may come into contact with the colored pencil lead of the refill case. In the present invention, a specific resin material is disposed in a portion of the refill case that may come into contact with the colored pencil lead.

[0076] Here, disposing a resin material in a specific part means, for example, forming that part with a resin material, disposing a component made of a resin material, or covering that part with a resin material. For example, in the case of a refill case having a shape like that shown in Figure 1, this can be achieved by forming the entire storage compartment with a specific resin material. Of course, the lid may also be formed with a resin material, or the inner surface of the storage compartment may be covered with a resin material.

[0077] In the present invention, if a specific resin material is disposed in a portion of the refill case that may come into contact with the colored pencil leads, adhesion of the colored pencil leads to the refill case can be suppressed. However, it is preferable that the ratio of the area where the specific resin material is disposed to the total area where the colored pencil leads and the refill case may come into contact is high. Specifically, the area where the specific resin material is disposed is preferably 50% or more, more preferably 80% or more, and particularly preferably 90% or more, of the total area of ​​the refill case that may come into contact with the colored pencil leads. Ideally, it is preferable that the specific resin material is disposed in all areas of the refill case that may come into contact with the colored pencil leads. Therefore, in the refill case of Figure 1, although depending on the dimensions, adhesion of the colored pencil leads can be suppressed by molding the storage section from a resin material with a specific SP value.

[0078] A lead refill case such as that shown in Figures 2 and 3 can also be used. This lead refill case has a lid 202 detachably attached to a storage compartment 201 that can store lead refills. In this lead refill case, the lid 202 has an engagement piece 202a protruding from its bottom end, and the storage compartment has a recess 201a that matches the engagement piece 202a. By forming the engagement piece 202a of the lid so that it matches the recess 201a of the storage compartment, the protrusion and recess engage with each other, allowing the lid to be stably attached to the storage compartment. The protrusion and recess can also be interchanged. In this lead refill case, the entire storage compartment 201 can be formed using a specific resin material to prevent colored pencil lead adhesion. The inner surface of the storage compartment 201 may also be coated with a specific resin material.

[0079] It is also possible to employ a lead refill case such as that shown in Figures 4 and 5. This case is also a lead refill case in which a lid 402 is detachably attached to a storage compartment 401 that stores colored pencil leads. The lid 402 has an engagement piece 402a protruding from its bottom end, and the storage compartment 401 has a recess 401a that matches the engagement piece 402a. By forming the engagement piece 402a of the lid so that it matches the recess 401a of the storage compartment, the protrusion and recess engage with each other, allowing the lid to be stably attached to the storage compartment. The protrusion and recess can also be interchanged. Even in this type of lead refill case, the entire storage compartment 401 can be formed using a specific resin material to prevent colored pencil leads from adhering to the storage compartment.

[0080] Furthermore, a lead refill case such as that shown in Figures 6 and 7 can be used. This case contains colored pencil leads in a storage compartment 601. By rotating the lid 602 around a rotation axis 602D, colored pencil leads can be stored in the storage compartment or removed from a lead outlet 603. Specifically, the colored pencil lead outlet 603 can be opened by rotating the lid 602 upright, and the outlet 603 can be closed by tilting the lid 602 sideways. In this lead refill case, a non-circular mounting hole 604E is formed in the lid fixing member 604, and a cutting groove 604F is formed in the lid fixing member 604 that crosses the mounting hole, allowing the mounting hole to be expanded. In addition, a cutting groove consisting of a circular arc is formed in the lid fixing member on the opposite side from the outlet, and a rotation axis 602D with a non-circular cross section is formed in the lid. The end of the case facing the rotating shaft is formed in a semicircular shape, and a raised portion of appropriate width is formed on the edge of the semicircular end from the front wall toward the back, and the rotating shaft of the lid is rotatably attached to the mounting hole of the lid fixing member. When the lid is tilted sideways to close the outlet, the rotating shaft of the lid engages with the mounting hole of the lid fixing member, and the raised portion covers the groove that crosses the mounting hole of the lid fixing member. When the lid is stood upright to open the outlet, the raised portion of the lid abuts against the stopper portion of the groove, which is made of an arc in the lid fixing member, stopping the rotation of the lid. Even in this type of refill lead case, the entire storage compartment 601 can be formed from a specific resin material to prevent colored pencil leads from adhering. [Example]

[0081] Examples of the present invention will be described below, but the present invention is not limited thereto.

[0082] [Manufacturing Example 1] [Kneading process, extrusion process, and firing process] Boron nitride 45 parts by mass Silica 45 parts by mass Polyvinyl alcohol 10 parts by mass 100 parts by mass of water The mixture was heated and kneaded in a kneader and a triple roll while evaporating water, and the resulting mixture was extruded to a predetermined diameter to obtain a linear molded product. This linear molded product was heated to 600°C at a rate of 10°C / hour in an argon gas atmosphere and held for 5 hours, then heated at 100°C / hour in an oxygen atmosphere and fired at 900°C for 1 hour to obtain a porous substrate with a porosity of 25% and a cross-sectional diameter of 0.55 mm.

[0083] [Impregnation process] Colorant (blue dye) 30 parts by weight High-boiling organic solvent (phenyl diglycol) 10 parts by mass Low boiling point organic solvent (ethyl alcohol) 50 parts by mass Resin (ketone resin) 10 parts by mass The above mixture was stirred at 30°C until it was uniformly mixed to obtain a colorant solution.

[0084] The porous substrate obtained in the baking step was immersed in the colorant solution heated to 30° C. and held for 6 hours.

[0085] [Drying process] The porous substrate that had undergone the impregnation step was held at 80° C. for 6 hours to evaporate and remove the low-boiling organic solvent in the pores of the porous substrate, thereby obtaining a porous core.

[0086] [Filling process] The porous core obtained in the drying process was immersed in silicone oil (SP value 7.3) heated to 80°C and held for 6 hours to obtain a colored pencil lead. Next, excess silicone oil adhering to the surface of the colored pencil lead was removed by centrifugation, yielding a colored pencil lead impregnated with 12.5% ​​by mass of silicone oil. Furthermore, thermogravimetry of this colored pencil lead confirmed that it contained phenyl diglycol. Its content was 1% by mass or more.

[0087] [Production Examples 2 to 10, Production Comparative Examples 1 to 3] Colored pencil leads were obtained in the same manner as in Production Example 1, except that the components were changed to those listed in Table 1. Thermogravimetry and the production conditions confirmed that the colored pencil leads of Production Examples 2 to 10 and Production Comparative Example 2 contained a high-boiling organic solvent. Note that in Production Comparative Examples 2 and 3, no low-volatility liquid was filled.

[0088] [Examples 1 to 10, Comparative Examples 1 to 3] The resulting colored pencil leads were placed in the refill case shown in Figure 2 to produce refill products. The resin material used in the storage section of this refill case is shown in Table 1, and more than 90% of the area of ​​the refill case that can come into contact with the colored pencil leads is made up of this resin material.

[0089] [Evaluation method for colored pencil lead adhesion] Each refill product was kept at 50°C for 14 days with the color pencil lead in contact with the inner surface of the refill case, and the adhesion of the lead was evaluated according to the following criteria.

[0090] (Adhesion evaluation criteria) A: The colored pencil lead does not adhere to the holder at all. B: The colored pencil lead slightly adheres to the holder, but is easily removed. C: Colored pencil lead stuck to the container

[0091] [Evaluation method for writing feel and handwriting color development] This paper is made from 100% chemical pulp and has a weight range of 40 to 157 g / m². 2 The writing feel at that time was evaluated by a sensory test (writing feel 1). The color development of the resulting handwriting was also evaluated (handwriting color development 1). Furthermore, after production, the baked colored pencil leads were left to stand in a 25°C environment for 4 weeks, and then used to write on the above-mentioned high-quality paper. The writing feel (writing feel 2) and the color development of the resulting writing (writing color development 2) were evaluated by a sensory test. (Evaluation criteria for writing quality 1 and 2) A: It writes very smoothly. B: Smooth writing possible. C: The writing feel is a bit rough and heavy. D: The writing feel is rough and heavy. (Evaluation criteria for handwriting color development 1 and 2) S: Very good color. A: Good color. B: Color is slightly inferior, but good. C: Poor color development. D: Writing is possible, but color development is very poor. E: Unable to write and handwriting is not visible.

[0092] [Table 1-1]

[0093] [Table 1-2] In the table: Blue dye B: Oil Blue 613 (manufactured by Orient Chemical Industry Co., Ltd.) Pink fluorescent pigment P1: NKS1007 (Nippon Fluorescent Chemical Co., Ltd., a mixture of polyamide resin and CI Basic Violet 11:1) Pink fluorescent pigment P2: MPI-507C (manufactured by Nippon Fluorescent Chemical Co., Ltd., a mixture of melamine, paratoluenesulfonamide, formalin polycondensation, and CI Basic Violet 11:1) Ester A: Adeka Cizer RS-1000 (carboxylic acid ester of polyalkylene glycol, manufactured by ADEKA Corporation, boiling point 250°C or higher) Ester B: Adeka Cizer RS-700 (carboxylic acid ester of polyalkylene glycol, manufactured by ADEKA Corporation, boiling point 250°C or higher) Ester C: Adeka Cizer RS-107 (adipic acid dibutoxyester, manufactured by ADEKA Corporation, boiling point 200°C or higher) SO: Dimethyl silicone oil (manufactured by Shin-Etsu Chemical Co., Ltd., trade name: KF-96-50cs, SP value: 7.3, surface tension: 20.8 N / m) OO: α-olefin (SP value: 8.0) LP: Liquid paraffin (SP value: 7.5~8.0) AS: Styrene acrylic nitrile resin (SP value 12.8) PC: Polycarbonate (SP value: 9.7) [Explanation of symbols]

[0094] 101 Storage unit 102 Lid 102a Bottom of the lid 103 Colored Pencil Lead 201 Storage Unit 201a Engagement piece 202 Lid 202a Recessed part 401 Storage Unit 401a Concavity 402 Lid 402a Engagement piece 601 Storage unit 602 Lid 602D Rotating Axis 603 Exit 604 Lid fixing member 604E mounting hole 604F Cutting groove

Claims

1. A refill product comprising a colored pencil lead and a refill case containing the lead, The colored pencil lead is Body material and an inorganic binder; A colorant; a high-boiling organic solvent capable of dissolving the colorant; a porous core comprising: A hardly volatile liquid that cannot dissolve the colorant comprising the high-boiling organic solvent is an aromatic glycol ether or an aliphatic glycol ether, and has a boiling point of 200°C or higher; the solubility parameter of the low-volatility liquid is 6 to 8; On a part of the inner surface of the refill case where the colored pencil lead may come into contact, A refill product characterized by disposing a resin material having a solubility parameter that differs from the solubility parameter of the low-volatility liquid by 1.5 or more.

2. 2. The refill product according to claim 1, wherein the resin material is disposed in an area of ​​50% or more of the entire area of ​​the refill case that can come into contact with the colored pencil lead.

3. 3. The colored pencil lead according to claim 1, wherein the low-volatility liquid is selected from the group consisting of silicone oil, fluorine-based oil, mineral oil, vegetable oil, and liquid paraffin.

4. The refill product according to any one of claims 1 to 3, wherein the resin material has a solubility parameter of 8.5 to 15.

5. The refill product according to any one of claims 1 to 4, wherein the high-boiling organic solvent is a carboxylic acid ester of a polyalkylene glycol or a carboxylic acid ester of an alcohol.

6. The refill product according to any one of claims 1 to 5, wherein the content of the high-boiling point organic solvent is 0.5 to 20% by mass based on the total mass of the colored pencil core.

7. The replacement lead case is A storage section for storing the color pencil lead; a lid portion that temporarily closes the opening provided in the storage portion and that can be deformed to allow the colored pencil lead to be removed; Equipped with The refill product according to any one of claims 1 to 6, wherein a part of the inner surface of the storage section is a part that can come into contact with the colored pencil lead.

8. The refill product according to any one of claims 1 to 7, wherein the colored pencil lead is a colored pencil lead for a mechanical pencil.

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