JP2024010516A - Packaging container for ink - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new packaging container for ink which is durable to deformation at high temperature and contains ink for a writing instrument.

SOLUTION: A packaging container for ink is filled with ink for an aqueous writing instrument, wherein the ink for the aqueous writing instrument contains water, a coloring material and an organic solvent having a hydroxyl group, the packaging container has an ink storage part having at least a paper layer and an inside resin layer brought into contact with the ink for the aqueous writing instrument, a vapor pressure at 20°C of the organic solvent having the hydroxyl group is 93 mmHg or less, and air is contained in the packaging container for the ink.

SELECTED DRAWING: None

COPYRIGHT: (C)2024,JPO&INPIT

Description

The present invention relates to a packaging container for ink.

In recent years, from the viewpoint of consideration to environmental issues, writing instruments having paper as a base material have been proposed in order to suppress the use of disposable plastics.

Patent Document 1 discloses a paper base material laminate including an inner layer of a paper base material, an intermediate layer formed on the outer peripheral surface of the inner layer and which is a metal layer or a silica vapor deposited layer, and a Further, a liquid storage member for an applicator is disclosed, which has at least three layers consisting of an outer layer made of a paper base material, and the paper base material of the inner layer has a density of 0.8 g/cm ³ or more. ing.

Patent Document 2 is characterized in that an ink storage tube is constructed using paper as a base material, and one end of the ink storage tube is coupled to a connecting portion formed on a writing member or a relay member that supports the writing member. An ink storage member for a writing instrument is disclosed.

Patent Document 3 discloses a brush having a lean inside, a bottle containing paint to be supplied to the brush, and a lid attached to the bottle, including an opening connected to the lean in the center, and the bottle. A brush type with a paint container, comprising a screw-on lid provided with a paint reservoir disposed externally adjacent to the opening and having a volume for storing paint, and a valve for supplying the paint from the bottle to the paint reservoir. A paint applicator is disclosed.

Note that Patent Document 4 discloses a paper container with a spout.

JP 2021-16976 Publication Japanese Patent Application Publication No. 2020-172044 Japanese Patent Application Publication No. 2000-51772 Japanese Patent Application Publication No. 2020-151832

The present invention provides a novel ink packaging container containing ink for writing instruments that can withstand deformation at high temperatures.

After intensive study, the present inventors found that the above-mentioned problem could be solved by the following means, and completed the present invention. That is, the present invention is as follows:
<Aspect 1> An ink packaging container filled with aqueous writing instrument ink,
The aqueous writing instrument ink contains water, a coloring material, and an organic solvent having a hydroxyl group,
The ink packaging container has at least an ink storage portion having at least a paper layer and an inner resin layer in contact with the aqueous writing instrument ink,
The organic solvent having a hydroxyl group has a vapor pressure of 93 mmHg or less at 20°C,
The ink packaging container contains air.
Packaging container for ink.
<Aspect 2> The ink packaging container according to aspect 1, wherein the organic solvent having a hydroxyl group has a vapor pressure of 50 mmHg or less at 20°C.
<Aspect 3> The ink packaging container according to aspect 1 or 2, wherein the content of the organic solvent is 20% by mass or less based on the mass of the aqueous writing instrument ink.
<Aspect 4> The ink packaging container according to any one of aspects 1 to 3, wherein the inner resin layer is a polyolefin resin.
<Aspect 5> The ink packaging container according to any one of aspects 1 to 4, which is a writing instrument.

According to the present invention, it is possible to provide a novel ink packaging container containing ink for writing instruments that can withstand deformation at high temperatures.

FIG. 1 is an overall perspective view of an ink packaging container of the present invention, which is a writing instrument. FIG. 1(a) is a perspective view of the state in which the cap part is fitted, FIG. 1(b) is a perspective view of the state in which the cap part is removed, and FIG. 1(c) is a perspective view of the state in which the writing part is removed. FIG. 3 is a perspective view of the removed state. FIG. 2 is an overall view of the ink packaging container of the present invention. FIG. 2(a) is a top view of the ink packaging container of the present invention. FIG. 2(b) is a front view of the ink packaging container of the present invention. FIG. 2(c) is a side view of the ink packaging container of the present invention. FIG. 2(d) is a side sectional view of the ink packaging container of the present invention. FIG. 3 is an explanatory diagram of writing using the ink packaging container of the present invention. FIG. 4 is a diagram showing carton blanks for obtaining an ink storage portion of the ink packaging container of the present invention. FIG. 5 is a diagram showing the structure of the writing part of the ink packaging container of the present invention. FIG. 5(a) is a top view of the writing section. FIGS. 5(b) and 5(c) are perspective views of the writing section. FIG. 5(d) is a front view of the writing section. FIG. 5(e) is a side view of the writing section. FIG. 5(f) is a cross-sectional view of the writing section taken along line ff in FIG. 5(a). FIG. 5(g) is a bottom view of the writing section. FIG. 5(h) is a cross-sectional view of the writing section taken along line hh in FIG. 5(a). FIG. 6 is a diagram showing the structure of an assembly consisting of a cap part, a writing part, and a spout part of the ink packaging container of the present invention. FIG. 6(a) is a top view of the assembly. FIG. 6(b) is a perspective view of the assembly. FIG. 6(c) is a front view of the assembly. FIG. 6(d) is a side view of the assembly. FIG. 6(e) is a cross-sectional view of the assembly taken along line ee of FIG. 6(a). FIG. 6(f) is a bottom view of the assembly. FIG. 6(g) is a cross-sectional view of the assembly taken along line gg in FIG. 6(a). FIG. 7 is a diagram showing the structure of the spout of the ink packaging container of the present invention. FIG. 7(a) is a perspective view of the plug portion. FIG. 7(b) is a top view of the spout. FIG. 7(c) is a sectional view of the spout section taken along line cc in FIG. 7(b). FIG. 7(d) is a front view of the plug part. FIG. 7(e) is a side view of the plug portion. FIG. 7(f) is a bottom view of the spout. FIG. 7(g) is a perspective view of the plug portion.

《Ink packaging container》
The ink packaging container of the present invention includes:
An ink packaging container filled with an aqueous writing instrument ink,
The aqueous writing instrument ink contains water, a coloring material, and an organic solvent having a hydroxyl group,
The ink packaging container has at least an ink storage portion having at least a paper layer and an inner resin layer in contact with the aqueous writing instrument ink,
The organic solvent having a hydroxyl group has a vapor pressure of 93 mmHg or less at 20°C,
The ink packaging container contains air.

The ink packaging container contains air in the space that exists between the aqueous writing instrument ink and the ink accommodating portion. When paper packaging containers are filled with ink containing organic solvents and stored for long periods of time, they may be exposed to high temperature environments during the long storage period. Container deformation may occur.

In response, the present inventors have developed packaging for ink that can suppress the volatilization of the organic solvent into the air by using the organic solvent in the ink as described above, and thereby can withstand deformation at high temperatures. Found out that you can get a container.

Each component of the present invention will be explained below.

<Water-based writing instrument ink>
Water-based writing instrument ink contains water, a coloring material, and an organic solvent having a hydroxyl group.

The aqueous writing instrument ink of the present invention may contain an optional surfactant.

The aqueous writing instrument ink of the present invention can be obtained by mixing the above-mentioned materials.

(water)
As water, purified water, ion-exchanged water, etc. can be used.

(color material)
As the colorant, various colorants that can be used in conventional inks can be used, such as dyes, pigments, or mixtures of dyes and pigments. These colorants may be used alone or in combination.

As the dye, all dyes that can be dissolved or dispersed in water can be used, such as acid dyes such as eosin, fuxin, water yellow #6-C, acid red, water blue #105, brilliant blue FCF, and nigrosine NB. Direct dyes such as Direct Black 154, Direct Sky Blue 5B, and Violet BB; Basic dyes such as Rhodamine and Methyl Violet.

Pigments include conventionally known inorganic and organic pigments such as titanium oxide, resin particle pigments containing pigments or dyes, pseudo-pigments obtained by coloring resin emulsions with dyes or pigments, white plastic pigments, bright pigments, and silica. Pigments, thermochromic pigments, photochromic particles, etc., which are based on mica or mica and whose surface is multilayer coated with iron oxide, titanium oxide, etc., can be used without limitation.

Examples of inorganic pigments include carbon black, titanium black, zinc white, red iron, aluminum, chromium oxide, iron black, cobalt blue, iron oxide yellow, viridian, zinc sulfide, lithopone, cadmium yellow, vermilion, cadmium red, and yellow. Lead, molybdade orange, zinc chromate, strontium chromate, white carbon, clay, talc, ultramarine, precipitated barium sulfate, barite powder, calcium carbonate, white lead, dark blue, dark blue, manganese violet, aluminum powder, brass powder, etc. Can be used.

Examples of organic pigments include azo lakes, insoluble azo pigments, chelate azo pigments, phthalocyanine pigments, perylene and perinone pigments, and nitroso pigments. Examples of such organic pigments include C.I. I. Pigment Blue 17, C. I. Pigment Blue 15, C. I. Pigment Blue 17, C. I. Pigment Blue 27, C. I. Pigment Red 5, C. I. Pigment Red 22, C. I. Pigment Red 38, C. I. Pigment Red 48, C. I. Pigment Red 49, C. I. Pigment Red 53, C. I. Pigment Red 57, C. I. Pigment Red 81, C. I. Pigment Red 104, C. I. Pigment Red 146, C. I. Pigment Red 245, C. I. Pigment Yellow 1, C. I. Pigment Yellow 3, C. I. Pigment Yellow 12, C. I. Pigment Yellow 13, C. I. Pigment Yellow 14, C. I. Pigment Yellow 17, C. I. Pigment Yellow 34, C. I. Pigment Yellow 55, C. I. Pigment Yellow 74, C. I. Pigment Yellow 95, C. I. Pigment Yellow 166, C. I. Pigment Yellow 167, C. I. Pigment Orange 5, C. I. Pigment Orange 13, C. I. Pigment Orange 16, C. I. Pigment Violet 1, C. I. Pigment Violet 3, C. I. Pigment Violet 19, C. I. Pigment Violet 23, C. I. Pigment Violet 50, C. I. Pigment Green 7 and the like.

The thermochromic pigment includes a leuco dye that functions as a color former, a color developer that is a component that has the ability to develop color from the leuco dye, and a color change temperature that can be controlled in the coloring of the leuco dye and color developer. Examples include thermochromic pigments produced by microencapsulating a thermochromic composition containing at least a discoloration temperature adjusting agent to a predetermined average particle size (for example, 0.1 to 6 μm). be able to. This average particle size may be, for example, 0.1 μm or more, 0.2 μm or more, 0.3 μm or more, 0.5 μm or more, 0.7 μm or more, or 0.9 μm or more, or 6 μm or less, 5 μm or less, 4 μm or less. Below, it may be 3 μm or less, 2 μm or less, or 1 μm or less.

As the photochromic particles, for example, photochromic particles composed of at least one kind selected from photochromic substances such as photochromic dyes (compounds) and fluorescent dyes, and a resin such as terpene phenol resin are used. be able to. In addition, the photochromic particles include at least one kind selected from photochromic substances such as photochromic dyes (compounds) and fluorescent dyes, an organic solvent, and antioxidants, light stabilizers, sensitizers, etc. Examples include photochromic particles produced by microencapsulating a photochromic composition containing an additive to a predetermined average particle size (for example, 0.1 to 6 μm). .

By suitably using the photochromic substance described above, the photochromic particles are colorless in, for example, an indoor lighting environment (indoor lighting equipment selected from incandescent lamps, fluorescent lamps, lamps, white LEDs, etc.). It may have the property of developing color in an ultraviolet irradiation environment (irradiation with a wavelength of 200 to 400 nm, irradiation environment with sunlight containing ultraviolet light).

In the present invention (including Examples, etc.), the "average particle diameter" is appropriately selected depending on the size of the particles to be measured, and in the case of particles of approximately less than 1 μm, the scattering intensity measured by dynamic light scattering method. In the distribution, it is the value of the histogram average particle diameter (D50) calculated on a volume basis, and in the case of particles of 1 μm or more, it is the value of the median diameter (D50) calculated on a volume basis in the laser diffraction method. The average particle diameter can be measured using a particle size analyzer [Microtrac HRA9320-X100 (Nikkiso Co., Ltd.)].

Examples of the microencapsulation method for the thermochromic pigment and the photochromic particles include interfacial polymerization, interfacial polycondensation, in situ polymerization, in-liquid curing coating, phase separation from an aqueous solution, and organic solvent. Examples include a phase separation method, a melt dispersion cooling method, an air suspension coating method, a spray drying method, etc., and can be appropriately selected depending on the application.

For example, in a phase separation method from an aqueous solution, a thermochromic microcapsule pigment can be produced by a method including the following steps, particularly a method including performing the following steps in this order:
(1) Heating and melting the leuco dye, color developer, and color change temperature regulator;
(2) Adding heated and melted leuco dye, color developer, and discoloration temperature adjusting agent to an emulsifier solution, heating and stirring to disperse in the form of oil droplets to prepare a dispersion liquid;
(3) As a capsule film agent, a resin material capable of forming a wall film such as urethane resin, epoxy resin, or amino resin, such as an amino resin solution, specifically, an amino resin such as an aqueous methylolmelamine solution, a urea solution, or a benzoguanamine solution A thermochromic microcapsule pigment is obtained by gradually adding a solution to the above-mentioned dispersion liquid and reacting the resin raw material to form a capsule film, and (4) producing a thermochromic microcapsule pigment. Filtering this dispersion containing.

In this thermochromic pigment, the coloring temperature and decoloring temperature of each color can be set to suitable temperatures by suitably combining the types and amounts of the leuco dye, color developer, and color change temperature regulator.

These coloring materials can be used alone or in combination of two or more. In addition, among these coloring materials, the average particle diameter of water-dispersible pigments, resin particle pigments, pseudo pigments, white plastic pigments, multilayer coated pigments, thermochromic pigments, photochromic particles, etc. Although it varies depending on the diameter, ink composition, viscosity, etc., it is desirable that the average particle diameter is 0.02 to 6 μm. This average particle diameter is, for example, 0.02 μm or more, 0.05 μm or more, 0.07 μm or more, 0.10 μm or more, 0.20 μm or more, 0.30 μm or more, 0.50 μm or more, 0.70 μm or more, or 0. It may be 90 μm or more, or it may be 6 μm or less, 5 μm or less, 4 μm or less, 3 μm or less, 2 μm or less, or 1 μm or less.

The content of these colorants can be increased or decreased as appropriate depending on the line density of the ink, but may be 0.1% by mass or more, 0.3% by mass or more, 0. .5% by mass or more, 0.7% by mass or more, 0.9% by mass or more, or 1.0% by mass or more, and 40% by mass or less, 35% by mass or less, 30% by mass or less, 25% by mass % or less, 20% by mass or less, 15% by mass or less, or 10% by mass or less.

(Organic solvent)
The organic solvent is an organic solvent having a vapor pressure of 93 mmHg or less at 20° C. among organic solvents having a hydroxyl group. This vapor pressure is 90 mmHg or less, 80 mmHg or less, 70 mmHg or less, 60 mmHg or less, 50 mmHg or less, 45 mmHg or less, 40 mmHg or less, 30 mmHg or less, 20 mmHg or less, 18 mmHg or less, 17.5 mmHg or less, 15 mmHg or less, 14 mmHg or less, 13 mmHg or less, 10 mmHg or less. g Below, it may be 8 mmHg or less, 5 mmHg or less, 4 mmHg or less, 3 mmHg or less, 2 mmHg or less, or 1 mmHg or less, or it may be more than 0 mmHg. The vapor pressure is preferably 50 mmHg or less, particularly 17.5 mmHg or less, from the viewpoint of suppressing deformation of the packaging container in a high-temperature environment.

As such an organic solvent, for example, hydroxyl group-containing aromatics, alcohols, polyhydric alcohols, glycol ethers, etc. can be used. These solvents may be used alone or in combination.

As the hydroxyl group-containing aromatic, for example, benzyl alcohol, ethylene glycol monophenyl ether, ethylene glycol monobenzyl ether, propylene glycol monophenyl ether, diethylene glycol monophenyl ether, diethylene glycol dibenzoate, dipropylene glycol dibenzoate, etc. can be used. .

Examples of alcohols include ethanol, n-propanol, isopropanol, n-butanol, isobutanol, tert-butyl alcohol, 1-pentanol, isoamyl alcohol, sec-amyl alcohol, 3-pentanol, tert-amyl alcohol, n- -Hexanol, methylamyl alcohol, 2-ethylbutanol, n-heptanol, 2-heptanol, 3-heptanol, n-octanol, 2-octanol, 2-ethylhexanol, 3,5,5-trimethylhexanol, nonanol, n- Decanol, undecanol, n-decanol, trimethylnonyl alcohol, tetradecanol, heptadecanol, cyclohexanol, 2-methylcyclohexanol, etc. can be used.

Examples of polyhydric alcohols include ethylene glycol, diethylene glycol, 3-methyl-1,3-butanediol, triethylene glycol, dipropylene glycol, 1,3-propanediol, 1,3-butanediol, 1,5- Pentanediol, hexylene glycol, octylene glycol, etc. can be used.

Examples of glycol ethers include ethylene glycol monohexyl ether, ethylene glycol mono-2-ethyl butyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, and diethylene glycol monomethyl ether. Butyl ether, triethylene glycol monobutyl ether, tetraethylene glycol monobutyl ether, 3-methyl-3-methoxy-1-butanol, 3-methoxy-1-butanol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether , propylene glycol monobutyl ether, propylene glycol tertiary butyl ether dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monobutyl ether, tripropylene glycol monomethyl ether, tripropylene glycol monobutyl ether, tetra Propylene glycol monobutyl ether and the like can be used.

The content of the organic solvent may be 3% by mass or more, 5% by mass or more, 7% by mass or more, or 10% by mass or more, and 30% by mass or less, 25% by mass or more, based on the entire mass of the aqueous ink composition. It may be less than or equal to 20% by weight, less than or equal to 17% by weight, less than or equal to 15% by weight, or less than or equal to 13% by weight. Among these, the content of the organic solvent is preferably 20% by mass or less from the viewpoint of suppressing deformation of the packaging container in a high-temperature environment.

(Adhesive resin component)
The adhesive resin component is a resin used for adjusting viscosity and improving adhesive strength, if necessary. As the fixing resin, for example, water-soluble resins, resin emulsions, etc. can be used. These adhesive resins may be used alone or in combination.

Examples of water-soluble resins include polyacrylic acid, water-soluble styrene-acrylic resin, water-soluble styrene-maleic acid resin, polyvinyl alcohol, polyvinylpyrrolidone, water-soluble maleic acid resin, water-soluble styrene resin, and water-soluble ester-acrylic resin. , ethylene-maleic acid copolymer, polyethylene oxide, water-soluble urethane resin, and the like can be used.

As the resin emulsion, at least one selected from polyolefin emulsions, acrylic emulsions, vinyl acetate emulsions, urethane emulsions, styrene-butadiene emulsions, styrene acrylonitrile emulsions, etc. can be used.

The content of the adhesive resin component is 3% by mass or more, 4% by mass or more, 5% by mass or more, or 6% by mass or more based on the mass of the writing instrument ink to improve the adhesiveness of the writing instrument ink. The content is preferably 20% by mass or less, 15% by mass or less, or 12% by mass or less from the viewpoint of making the viscosity of the writing instrument ink appropriate.

(other ingredients)
As other components, for example, surfactants, pH adjusters, viscosity adjusters, preservatives, etc. can be used.

<Packaging container>
In the present invention, the packaging container is a packaging container in which the above-mentioned writing instrument ink is stored. This packaging container may be composed only of the ink storage section, or may include other members.

Moreover, the packaging container of the present invention may be in the form of a writing instrument. In this case, the other member may be, for example, a writing section. One embodiment of the packaging container of the present invention, which is a writing instrument, will be described with reference to the drawings.

<Writing instruments>
As shown in FIGS. 1 and 2, the packaging container 100 of the present invention may include an ink storage section 10, a writing section 20, a cap section 30, and a spout section 40.

According to the packaging container 100 of this aspect, as shown in FIG. 3, writing can be performed with the writing part 20 pressed against the writing surface 200.

(Ink storage section)
The ink storage section is a member that stores ink.

The ink storage portion has at least a paper layer and an inner resin layer in contact with the water-based writing instrument ink.

The ink storage section is composed of a laminate having at least a paper layer and an inner resin layer. For example, the ink storage section is formed by forming a carton blank 10a as shown in FIG. 4, which is made of the above-mentioned laminate, into a cylindrical shape, with the solid line in FIG. 4 being a mountain fold and the broken line being a valley fold. can be manufactured by adhering. For a specific manufacturing method, the description in Patent Document 3 can be referred to.

(Ink storage section: paper layer)
As the paper layer, a paper layer commonly used in paper containers can be used.

(Ink storage section: inner resin layer)
The inner resin layer is a resin layer that is in contact with the water-based writing instrument ink.

Examples of the resin constituting the inner resin layer include polyolefin resin, ketone resin, sulfamide resin, maleic acid resin, terpene resin, terpene phenol resin, ester gum, xylene resin, alkyd resin, phenol resin, rosin, polyvinylpyrrolidone, and polyvinyl butyral. , polyvinyl alcohol, acrylic resin, urethane resin, melamine resin, cellulose resin, etc., and derivatives thereof can be used.

As the polyolefin resin, polyethylene, polypropylene, etc. can be used.

The arithmetic mean roughness Sa of the surface of the inner resin layer in contact with the aqueous writing instrument ink measured in accordance with ISO 25178 may be 50 μm or less, 40 μm or less, 30 μm or less, 20 μm or less, or 10 μm or less. , or 1 μm or more, 3 μm or more, or 5 μm or more.

(Ink storage section: other layer)
As other layers, a barrier layer, an adhesive layer, etc. can be used.

As the barrier layer, a metal foil layer such as an aluminum foil, a metal vapor deposition layer such as an aluminum oxide vapor deposition film, a silica layer, etc. can be used. These layers may be laminated separately to the paper layer or the inner resin layer, or may be laminated in advance to the paper layer or the inner resin layer.

As the adhesive layer, for example, a dry lamination adhesive or the like can be used.

(writing department)
As shown in FIG. 5, the writing section 20 may include an ink supply section 22 and a joint section 24.

The ink supply section may have a structure that is joined to the joint section and can supply ink from the ink storage section, for example, by capillary action. Examples of the ink supply section include cores used in common writing instruments, such as fiber cores and plastic cores, molded into a shape that can fit into the joint.

Fiber cores include natural fibers, animal hair fibers, polyacetal resins, acrylic resins, polyester resins, polyamide resins, polyurethane resins, polyolefin resins, polyvinyl resins, polycarbonate resins, polyether resins, and polyphenylene resins. The core is a parallel fiber bundle made of one type or a combination of two or more types of resin, a fiber bundle such as felt, or a core made by processing these fiber bundles with a resin.

The plastic core is a core in which an ink groove for supplying ink from an ink storage portion is formed in the longitudinal direction of a rod-shaped resin. This rod-shaped resin may be composed of the resins listed for the fiber core.

The joining part is a part for joining the writing part to the spout part. Thereby, only the writing part can be removed from the spout part. According to this aspect, when the writing part is worn out, only the writing part can be replaced with a new one, and when the ink in the container is used up, a new ink storage part filled with ink can be attached. This allows the writing section to be reused and the ink storage section to be used repeatedly.

(Cap part)
The cap part is a member for hiding the writing part. As shown in FIG. 6, the cap portion 30 may have a joint portion 32 for joining to the outer joint portion 46 of the spout portion 40, or a structure for joining to the writing portion (not shown). .

The joint portion is a portion for joining the cap portion to the outer joint portion of the spout portion. This joining portion may be a portion that allows joining by fitting, screwing, or the like.

(Spout part)
The spout portion may be coupled to the ink storage portion. As shown in FIG. 7, the plug portion 40 may be constructed of one member, and may have an opening 42, an inner joint portion 44, and an outer joint portion 46.

The opening is a portion for supplying ink from the ink storage section to the ink supply section of the writing section. Through this opening, it is possible to refill the ink reservoir with ink or to pour ink into another container.

The inner joint part is a part for joining the writing part to the spout part. The outer joint part is a part for joining the cap part to the spout part. These joint parts may be parts that enable joining by fitting, screwing, or the like.

The present invention will be specifically explained with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

《Preparation of ink for writing instruments》
Inks for writing instruments of Examples 1 to 6 and Comparative Examples 1 to 2 were prepared by mixing the materials shown in Table 1 in the amounts shown in Table 1.

Details of each component are as follows:
Titanium oxide: titanium oxide, GT-100, Sakai Chemical Industry Co., Ltd.)
Aluminum: Aluminum pigment, EMR-D6390, Toyo Aluminum Co., Ltd. Red dye: FUJI RED 2510, Fuji Shiki Co., Ltd. Pink dye: Pink, NKW3207E, Japan Fluorescent Co., Ltd. Thermochromic MC: Black, thermochromic microcapsule pigment (3 μm)
PGM: Propylene glycol monomethyl ether Styrene acrylic: Joncryl 63J, BASF

Each of the produced inks was filled into paper packaging containers to produce packaging containers of Examples 1 to 6 and Comparative Examples 1 to 2. A polyethylene film with a surface roughness of 5.4 μm was used as the inner resin layer of the packaging container.

《Evaluation of deformation resistance at high temperatures》
The packaging container was allowed to stand for one week in an environment with a temperature of 40° C. and a humidity of 30%, and after returning to room temperature, the appearance of the packaging container was visually confirmed. The evaluation criteria are as follows.
A: No deformation occurred, and no deformation occurred even after being left for one week.
B: No deformation occurred.
C: Slightly deformed.
D: Obviously deformed.

Table 1 shows the configurations and evaluation results of Examples and Comparative Examples.

Table 1 shows that the packaging containers of Examples 1 to 6 filled with writing instrument inks that have hydroxyl groups and have a vapor pressure of 93 mmHg or less at 20°C have good deformation resistance at high temperatures. You can understand something.

100 Ink packaging container 10 Ink storage section 10a Carton blanks constituting the ink storage section 20 Writing section 22 Ink supply section 24 Joint section 30 Cap section 32 Joint section 40 Spout section 42 Opening section 44 Inner joint section 46 Outer joint section 200 writing surface

Claims (5)

An ink packaging container filled with an aqueous writing instrument ink,
The aqueous writing instrument ink contains water, a coloring material, and an organic solvent having a hydroxyl group,
The ink packaging container has at least an ink storage portion having at least a paper layer and an inner resin layer in contact with the aqueous writing instrument ink,
The organic solvent having a hydroxyl group has a vapor pressure of 93 mmHg or less at 20°C,
The ink packaging container contains air.
Packaging container for ink. The ink packaging container according to claim 1, wherein the organic solvent having a hydroxyl group has a vapor pressure of 50 mmHg or less at 20°C. The ink packaging container according to claim 1 or 2, wherein the content of the organic solvent is 20% by mass or less based on the mass of the aqueous writing instrument ink. The ink packaging container according to claim 1 or 2, wherein the inner resin layer is a polyolefin resin. The ink packaging container according to claim 1 or 2, which is a writing instrument.

Images