JP7258978B2 - Pen core for applicator - Google Patents

Description

The present invention relates to a pen core for an applicator (including a writing instrument), and more specifically, an applicator that is highly compatible with porosity, coating liquid (including ink) outflow, and physical strength (shear strength, breaking strength). It relates to pen cores for pens.

Conventionally, pen cores used for writing or applicators include, for example, 1) fiber cores obtained by processing or resin-processing fiber bundles, sintered bodies of thermoplastic resin powder (see, for example, Patent Document 1); ) A pen core composed of two or more types of laminated structures, characterized in that the tip portion is made of a sintered body of thermoplastic resin powder, and the shaft portion has an ink guide hole formed therein in the longitudinal direction. 3) A pen nib for a writing instrument made of a fiber bundle obtained by bundling fibers and bonding and curing with a binder resin, in which at least the writing surface of the fiber bundle and 4) a cylindrical body having a tip shape suitable for application; A tip body having a hole disclosed in the publication, which is formed by sintering ultra-high molecular weight polyethylene powder with a porosity of about 75 to 85%, particularly about 80%, and a hole in the tip body. A tip body (see, for example, Patent Literature 4) is known, which is characterized by comprising a filling embedded in a body.

However, in each of the pen cores and the like in Patent Documents 1 to 4, the sintered body made of thermoplastic resin powder has excellent functions because the shape can be freely designed, but there are problems such as porosity and ink flowability. When trying to increase the physical strength (shear strength, breaking strength), problems such as decrease occur.

JP 2014-50967 A (claims, paragraph 0016) JP 2014-50977 A (Claims, FIG. 1) Japanese Patent Application Laid-Open No. 2004-98518 (Claims, FIGS. 1 and 2) Japanese Patent Laying-Open No. 2014-83699 (Claims, FIGS. 1 to 4, etc.)

In view of the above-mentioned problems of the prior art, the present invention is intended to solve them, and achieves a high degree of compatibility between porosity, coating liquid (including ink) outflow, and physical strength (shear strength, breaking strength). An object of the present invention is to provide a pen core for an applicator.

As a result of intensive studies in order to solve the above-mentioned conventional problems, the inventors of the present invention have found a pen core for an applicator, which comprises a specific thermoplastic resin and a thermoplastic resin having specific physical properties. The inventors have found that a pen core for an applicator for the above-mentioned purpose can be obtained by forming a sintered body obtained by sintering (1) and (2), and have completed the present invention.

That is, the pen core for an applicator of the present invention is a pen core for an applicator, and the pen core for an applicator is a sintered body obtained by sintering a granular thermoplastic resin and a fibrous thermoplastic resin. characterized by consisting of
The thermoplastic resin is polyethylene, polymethyl methacrylate, polypropylene, ethylene-vinyl acetate copolymer, polystyrene, styrene-acrylonitrile copolymer, acrylonitrile-butadiene-styrene copolymer, polyamide, polycarbonate, polytetrafluoroethylene, polyvinylidene fluoride At least one selected is preferable.
The content ratio [(A):(B)] of the granular thermoplastic resin (A) and the fibrous thermoplastic resin (B) is preferably 20-80% by mass:80-20% by mass.
The sintered body preferably has a porosity of 30 to 70%.

ADVANTAGE OF THE INVENTION According to this invention, the pen core for applicator implements highly compatible with porosity, outflow property of coating liquid (including ink), and physical strength (shear strength, breakage strength) is provided.

1 is a front view showing an example of an embodiment of a pen core for an applicator according to the present invention; FIG. 1 shows an example of an applicator using the pen core for an applicator of the present invention, in which (a) is a longitudinal sectional view, (b) is a plan view, and (c) is a front view. (a) to (f) are respective drawings showing an example of a holder that holds the pen core for the applicator in the applicator of FIG. 2, (a) is a plan view, (b) is a front view, ( c) is a vertical cross-sectional view, (d) is a left side view, (e) is a right side view, and (f) is a central transverse cross-sectional view. (a) to (f) are drawings showing an example of a state in which the pen core for the applicator is attached to the holding body of FIG. 3, (a) is a plan view, (b) is a front view, and (c). is a vertical cross-sectional view, (d) is a left side view, (e) is a right side view, and (f) is a central transverse cross-sectional view. (a) to (n) are front views or partial front views respectively showing examples of other embodiments of the pen core for applicator of the present invention. (a) to (j) show other embodiments of the pen core for the applicator of the present invention, and (a) is a sintered core body in which coating liquid grooves (ink grooves) are formed inside in the axial direction. 2(b) to 2(j) are transverse cross-sectional views showing respective examples of coating liquid grooves (ink grooves) formed inside in the axial direction. It is explanatory drawing which shows an example of a direct liquid type applicator which shows the other example of the applicator using the pen core for applicators of this invention in a cross-sectional aspect. FIG. 10 is an explanatory view showing an example of an applicator provided with a valve mechanism, showing another example of the applicator using the pen core for an applicator of the present invention, in a cross-sectional view. Fig. 10 is an explanatory view showing another example of an applicator using the pen core for applicator of the present invention, showing an example of a type of applicator in which a coating liquid is occluded in an occlusive body such as batting, in a cross-sectional view. FIG. 10 is an explanatory view showing an example of a knock-type applicator showing another example of the applicator using the pen core for applicator of the present invention in a cross-sectional mode.

EMBODIMENT OF THE INVENTION Below, it demonstrates in detail, referring drawings for embodiment of this invention.
FIG. 1 is a front view showing an example of an embodiment of the pen core for applicator of the present invention.
The pen core for an applicator of the present invention is composed of a sintered body obtained by sintering a granular thermoplastic resin and a fibrous thermoplastic resin.

Granular thermoplastic resins used in the present invention include polyethylene having an average particle size of 5 to 500 μm, polymethyl methacrylate, polypropylene, ethylene-vinyl acetate copolymer (EVA), polystyrene (PS), styrene-acrylonitrile copolymer (AS ), acrylonitrile-butadiene-styrene copolymer (ABS), polyamide, polycarbonate, polytetrafluoroethylene, and polyvinylidene fluoride.
Particularly preferably, by using a thermoplastic resin having an average particle size of 10 μm or more, the ink outflow property is increased when it is made into a sintered body, and by using a thermoplastic resin having an average particle size of 300 μm or less, the pen tip is improved in writing. The writing feeling when contacting the surface can be improved. In the present invention, the "average particle size" means the average value of the diameters of particles measured with an electron microscope, and the particle size measured for 20 particles in the image projected on the electron microscope. Average value. If the particle is not circular, add the length of the longest line segment and the length of the shortest line segment connecting any two points on the outline forming the pore, and divide the resulting value by 2. The particle size of

The fibrous thermoplastic resin used in the present invention includes polyethylene, polymethyl methacrylate, polypropylene, ethylene-vinyl acetate copolymer (EVA), polystyrene (PS), styrene-acrylonitrile copolymer (AS), acrylonitrile-butadiene- At least one selected from styrene (ABS) copolymers, polyamides, polycarbonates, polytetrafluoroethylene, and polyvinylidene fluoride is made into fibers, preferably having a fineness of 1 to 100 dtex, more preferably 3 to 30 dtex. Those having an average fiber length of 0.1 to 2 mm are preferred, and those having an average fiber length of 0.2 to 1 mm are more preferred.
By using a fibrous thermoplastic resin having these fineness ranges (1 to 100 dtex) and average fiber length (0.1 to 2 mm), it is possible to further achieve both strength and flowability.

The pen core for an applicator of the present invention is produced by sintering the granular thermoplastic resin and the fibrous thermoplastic resin, specifically, the granular thermoplastic resin and the fibrous thermoplastic resin. or kneaded with an additive such as a surfactant, and then pressure-molded in a mold that conforms to the shape of the pen core for the applicator, then dried and then baked, or the above granular thermoplastic resin It is kneaded with a fibrous thermoplastic resin, or kneaded with an additive such as a surfactant, poured into a mold that conforms to the shape of a pen core for an applicator, solidified, dried, baked, etc. is possible.
The baking temperature and baking time vary depending on the shape, size, application, type of thermoplastic resin, etc. of the pen core for the applicator, but in the range of 110 to 180 ° C., the baking time is 10 minutes to 10 hours. Baking is preferred.

In the present invention, the physical properties (average particle diameter, average fiber length, fineness) of the granular thermoplastic resin (A) and the fibrous thermoplastic resin (B) used, the granular thermoplastic resin (A) and the fibrous thermoplastic resin (A) By appropriately combining the content ratio and combination of the plastic resin (B), the sintering temperature and time, etc., a predetermined porosity, coating liquid (including ink) outflow property, and physical strength (shear strength, breaking strength) can be obtained. A satisfactory pen core for applicator can be obtained.
The content ratio of the granular thermoplastic resin (A) and the fibrous thermoplastic resin (B) used [(A):(B)] is preferably 30 to 90% by mass: 10 to 70% by mass. is preferred, more preferably 60 to 90% by mass: 10 to 40% by mass.
By setting the content ratio of (A) and (B) to 60 to 90% by mass and 80 to 20% by mass, it is possible to obtain a pen core for an applicator that further exhibits the effects of the present invention.
Particularly preferably, the granular thermoplastic resin (A) and the fibrous thermoplastic resin (B) are preferably made of the same thermoplastic resin from the viewpoint of sinterability. If the resin (A) is made of polyethylene, the fibrous thermoplastic resin (B) can be made of polyethylene.

The pen core for an applicator of the present invention is obtained by sintering the above-described granular thermoplastic resin and fibrous thermoplastic resin to form a sintered body. It varies depending on the use of the tool (for writing instruments, underline markers, felt-tip pens, writing board pens, and for applicators, cosmetic liquid applicators, correction liquid applicators, chemical liquid applicators, and paint liquid applicators). A porosity of 30 to 70% is preferred, and a porosity of 45 to 65% is particularly preferred. In the present invention, "porosity" refers to the volume ratio of voids to the apparent volume of the porous body, and is calculated as follows. First, a pen core for an applicator having a known mass and apparent volume is immersed in water, and the mass is measured in a state in which the core is taken out of the water after it is sufficiently soaked with water. From the measured mass, the volume of water permeated into the pen core for applicator is derived. Assuming that the volume of this water is the same as the pore volume of the pen core for applicator, the porosity is calculated from the following formula (A).
Porosity (unit: %) = (volume of water) / (apparent volume of pen core for applicator) x 100 (A)

The shape, internal structure, etc. of the pen core for applicator of the present invention are not particularly limited, and it is used for various applicator applications, that is, for writing instruments, such as underline markers, felt-tip pens, and pens for writing boards. A pen core for an applicator having a suitable shape can be used, and if it is for an applicator, it can be used for a cosmetic liquid applicator, a correction liquid applicator, a chemical liquid applicator, a coating liquid applicator, etc. A tool pen core can be used.
Each applicator using these applicator pen cores, such as each shape of the applicator pen core of the present invention, will be described in detail below with reference to the drawings.

Examples of the pen core for an applicator of the present invention include a pen core for an applicator having a shape shown in FIG.
As shown in FIG. 1, the pen core 10 for the applicator has a substantially U-shaped shape as a whole. and an inclined writing part 12 leading out.
The applicator pen core 10 is obtained by sintering the above-described granular thermoplastic resin and fibrous thermoplastic resin by the above-described sintering method to form a sintered body.
The applicator pen core 10 is obtained by sintering a granular thermoplastic resin and a fibrous thermoplastic resin. It becomes a structure in which the body is kneaded. As a result, the porosity, the outflow property of the coating liquid, and the physical strength (shear strength, breakage strength) can be highly compatible (this point will be further described in Examples, etc.).

FIG. 2(a) is a longitudinal sectional view showing an example of an applicator using the pen core 10 for applicator shown in FIG. 1, (b) is a plan view, (c) is a front view, and FIG. 4(a) to 4(f) show an example of a holder for holding the pen core for the applicator in the applicator of FIG. 2, and FIGS. It is each drawing which shows an example of the state which attached the pen core for tools.
The applicator A using the pen core 10 for applicator includes, as shown in FIG.

The shaft 20 is made of, for example, a thermoplastic resin, a thermosetting resin, or the like, and as shown in FIG. and a front barrel 25 to which a holder 40 to which the pen core 10 for applicator is attached is fixed.
The rear barrel 21 is made of resin such as polypropylene (PP) and formed into a cylindrical shape with a bottom, and functions as the main body (barrel) of the writing instrument. As shown in FIG. 2(a), the rear shaft 21 is provided with a holding member 23 consisting of holding pieces 22, 22, . The entire rear barrel and the front barrel, which will be described later, are molded opaque or transparent (and translucent), but either may be adopted from the viewpoint of appearance or practical use. Further, the front barrel 25 is fixed to the front side of the rear barrel 21 by fitting or the like. When thermochromic ink is used as the writing instrument ink, it is preferable to form a thermoplastic elastomer on the outer surface or the rear end of the rear barrel 11 so that the barrel can easily generate frictional heat by rubbing. .
The front barrel 25 is provided with a convex fitting portion 16 for fixing the body portion 41 of the holder 40 for fixing the pen core 10 for applicator. The front barrel 25 having this structure is molded from a resin such as polypropylene (PP), for example.

The application liquid occlusion body 30 is impregnated with ink for writing instruments such as water-based ink, oil-based ink, and thermochromic ink, cosmetic liquid, correction liquid, chemical liquid, and the like. , acrylic resins, polyester resins, polyamide resins, polyurethane resins, polyolefin resins, polyvinyl resins, polycarbonate resins, polyether resins, polyphenylene resins, etc. Fibers made of one or a combination of two or more It includes processed fiber bundles such as bundles and felt, and porous bodies such as sponges, resin particles, and sintered bodies. The coating liquid occluding body 30 is accommodated and held in the rear barrel 21 which is the main body portion of the barrel 20 . In addition, the ink composition to be used is not particularly limited, and suitable formulations such as water-based ink, oil-based ink, and thermochromic ink can be used depending on the application of the writing instrument. Fluorescent dyes such as Basic Violet 11, Basic Yellow 40, thermochromic microcapsule pigments, and the like can be included.

As shown in FIGS. 2(a) and 3(a) to 3(f), the holding body 40 includes a bulging body portion 41, a flange portion 42 on the front side of the body portion 41, and a writing direction. and a rear holding portion 45 having holding pieces 44 connected to the main body portion 41 on the rear side of the main body portion 41 . A holding groove 46 for fitting and holding the U-shaped writing core 30 before deformation is formed on the entire longitudinal outer peripheral surface of the holding body 40 composed of these members.
Further, a recessed fitting portion 41a is formed on the width direction outer peripheral surface of the main body portion 41, and air circulation grooves 41b, 41b are formed on the longitudinal direction outer peripheral surface.
In this form, the front surface portion 47 of the holding groove 46, which is the portion of the pen core 10 for applicator that comes into contact with the writing portion 12, prevents the writing portion 32 from slipping during writing, etc., and reliably holds the writing portion 32. A non-smooth surface portion 48 is formed in which uneven steps for smoothing are formed in a fine uneven shape.

The entire holding body 40 configured in this way is made of a material having visibility and flexibility, such as PP, PE, PET, PEN, nylon (amorphous other than general nylon such as 6 nylon, 12 nylon, etc.). By molding from a material such as nylon, acrylic, polymethylpentene, polystyrene, ABS, etc., characters written in the writing direction can be effectively visually recognized in the visible part 43 . Note that only the visible portion 43 may be made of a material having visibility.
In addition, the holder 40 may be configured using one type of each of the materials described above, or two or more types of materials from the viewpoint of further improving durability and visibility, such as injection molding and blow molding. can be molded by various molding methods.

In the applicator A of this configuration, the applicator portion 12 of the applicator pen core 10 is inclined (knife cut), and the applicator pen core 10 is fitted into the holding groove 46 of the holder 40 to The structure is securely fixed. Also, when the pressure or the like in the shaft 20 increases, ink drips or the like may occur from the pen core. It is adjusted with the outside air. The cap 50 is detachably attached to the distal end side outer peripheral surface of the front barrel 25 by fitting or the like. When thermochromic ink is used as writing instrument ink, it is preferable to form a thermoplastic elastomer on the outer surface of the cap 50 or on the top of the cap 50 so that the cap can easily generate frictional heat by rubbing.

In the applicator A using the pen core 10 for an applicator of the present invention, an occluding body 30 storing ink for a writing instrument or the like is inserted and held in the rear barrel 21 constituting the barrel 20 of the applicator, and the front barrel is held. 25. The applicator A can be easily manufactured by attaching the pen core 10 for the applicator made from the sintered body described above to the holder 40 having the above structure, and the applicator A can be occluded by the application liquid occluding body 20. The applied liquid is efficiently supplied to the application portion 12 of the pen core 10 for the applicator by capillary force, and is used for application.

In the applicator A configured as described above, the applicator pen core 10 is made of a sintered body obtained by sintering a granular thermoplastic resin and a fibrous thermoplastic resin. It is possible to achieve a high degree of compatibility between the coating liquid (including ink) outflow property and physical strength (shear strength, breakage strength), and to obtain an applicator excellent in durability, usability, etc.
Further, in the applicator A, as described above, the holder 40 that holds the pen core 10 for an applicator is made of a material having visibility. , It is a visible part that allows you to visually recognize the writing direction, and it can provide sufficient visibility so that you can reliably see the characters written in that direction and the applied part, and it can be used until the end of application. An applicator will be provided.

In the present invention, other specific shapes of the pen core 10 for applicator include, for example, those shown in FIGS. 5(a) to 5(n). Further, a pen core for an applicator in which an application groove is formed inside in the axial direction [Fig. 6(a)] can also be used. and the like.
Applicators using these pen cores 10 for applicators are used for applicators of various mechanisms, such as direct liquid applicators, batting applicators, applicators equipped with a valve mechanism, knock-type applicators, and the like. Applications include marking pens, sign pens, brush pens, writing board pens, thermochromic pens, etc. For applicators, cosmetic liquid applicators, correction liquid applicators, chemical applicators, paint liquids Examples include applicators.

FIG. 7 shows an example of a direct liquid applicator, and the direct liquid applicator B has an application liquid tank portion 60 serving as a shaft for directly storing the application liquid such as ink without allowing it to be absorbed by a batting or the like. In addition, in the front part of the coating liquid tank part 60, when the air in the coating liquid tank part 60 expands due to a temperature rise, etc., the coating liquid pushed out from the coating liquid tank does not drop from the pen tip or the air hole. An application liquid holding body (collector member) 61 for temporarily holding the liquid is built in, and the tip of the collector member 61 is provided with the above-described pen core 10 for an applicator of the present invention. The application liquid is led out from the application liquid tank section 60 to the applicator pen core 10 through the relay core 62 provided with the application liquid flow path attached to the center hole 61 a of the collector member 61 from the application liquid tank section 60 . This is performed by leading the coating liquid to the pen core 10 for applicator. In FIG. 7, 63 is a holder member, 64 is a rear shaft fixed to the rear portion of the coating liquid tank portion 60, and 65 is a cap. Alternatively, the rear portion of the applicator pen core 10 may be directly placed in the coating liquid tank portion 60 to lead out the coating liquid without interposing the relay core 62 .
The applicator C shown in FIG. 8 is a valve valve type writing instrument with a built-in hard ball 70 serving as an agitation ball. The coating liquid is supplied to the pen core 10 for the applicator of the present invention via the valve mechanism 72 . 8, 73 is a holder member, 74 is a holding member interposed between the valve mechanism 72 and the holder member 73 and holds the rear portion of the applicator pen core 10, and 75 is a cap.

FIG. 9 shows an applicator of a type in which a coating liquid such as ink is absorbed in a coating liquid absorbing member such as cotton. This type of applicator D has a coating liquid occluding body 81 in which a coating liquid is occluded in a fibrous body such as batting inside a shaft body 80 serving as a shaft body. The coating liquid of the coating liquid occluding body 81 is supplied to the pen core 10 for the applicator by abutting the rear end portion 10a of the pen core 10 for the applicator according to the invention. 82 is a tail plug fixed to the rear end of the shaft body 80, and 83 is a cap.
FIG. 10 shows a knock-type applicator that eliminates the need for a pen-type cap, in which the coating liquid is absorbed in a coating liquid occlusion body such as batting. The applicator E includes a coating liquid occluding body 91 in which a coating liquid is occluded in a fibrous body such as batting in a shaft body 90. At the front part of the coating liquid occluding body 91 is the above-described pen core for an applicator of the present invention. The application liquid of the application liquid occlusion body 91 is supplied to the pen core 10 for the applicator by the rear end portion 10a of the applicator 10 being brought into contact. A knock portion 92 is attached to the rear end portion of the shaft 90 . By pushing the knock portion 92 forward, the applicator pen core 10 comes out of the shaft 90 and enters the application state. The applicator pen core 10 is housed in the shaft body 90 by operating .

The pen core for an applicator of the present invention is not limited to the above-described embodiments, and various modifications can be made without changing the technical idea of the present invention.
The technical idea of the present invention is a pen core for an applicator, characterized in that the pen core for an applicator comprises a sintered body obtained by sintering a granular thermoplastic resin and a fibrous thermoplastic resin. Therefore, the shape of the writing lead is the same as that of the above-described embodiment, shown in FIG. For example, it may be a pen core for an applicator having a shape along FIGS. 5 and 6, and its shape, internal structure, size, etc. are not particularly limited.

2 to 10, in the applicator using the pen core for applicator of the present invention, the pen core for applicator 10 is a single type writing instrument. A twin-type applicator provided on both sides of the tool body may also be used.

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples.

[Example 1]
An applicator and ink conforming to the following configuration and FIGS. 1 to 4 were used. The dimensions of the applicator pen core 10, holder 40, etc. were as follows.

(Structure of pen core 10 for applicator)
<Granular thermoplastic resin>
Polyethylene (PE) powder (melting point 130° C.) with an average particle size of 5 μm was used.
<Structure of fibrous thermoplastic resin>
A polyethylene (PE) fiber (melting point 130° C.) having a fineness of 3 dtex and an average fiber length of 1 mm was used.
<Production of sintered body>
80% by mass of the granular thermoplastic resin and 20% by mass of the fibrous thermoplastic resin are kneaded and pressure-molded in a mold conforming to the shape of the pen core for the applicator shown in FIG. After baking at 130° C. for a baking time of 60 minutes, a pen core 10 for applicator made of a sintered body (porosity of 60%) was obtained.
(Configuration of holder 40)
Made of acrylic resin, visible light transmittance 85% [Reflectance was measured with a multi-light source spectrophotometer (MSC-5N) manufactured by Suga Test Instruments Co., Ltd., and was taken as visible light transmittance. ]
Size of visible part 43 (rectangle) after attaching writing lead: 5 mm x 6 mm x 3 mm x 4 mm
Non-smooth surface portion 48: uneven shape: length 2.0 mm, uneven step: 0.1 mm

(Structure of pen core 10 for applicator, writing implement member other than holder 40, and coating liquid)
Ink absorbing material: PET fiber bundle, porosity 85%, φ6×77mm
Writing instrument body, cap: made of polypropylene (PP) (coating liquid composition)
As the coating liquid, an ink for writing instruments having the following composition (100% by mass in total) was used.
Humectant: trimethylglycine (glycine betaine) 7.5% by mass
Pentaerythritol 4.5% by mass
Coloring agent: NKW-4805 yellow (manufactured by Nippon Fluorescent Co., Ltd.) 40.0% by mass
Antiseptic: 0.3% by mass of Bioace (manufactured by Kei Kasei Co., Ltd.)
pH adjuster: triethanolamine 1.0% by mass
Fluorinated surfactant: Surflon 8111N (manufactured by AGC Seimi Chemical Co., Ltd.) 0.2% by mass
Water-soluble organic solvent: Ethylene glycol 3.0% by mass
Water (solvent): ion-exchanged water 43.5% by mass

(Configuration of pen core for applicator for comparison)
As a pen core for an applicator for comparison, a pen core for an applicator (porosity of 60%) composed of a sintered body using the polyethylene (PE) powder (melting point: 130° C.) having an average particle size of 5 μm was produced.

When writing was performed using the applicator A using the pen core 10 for an applicator of Example 1, it was confirmed that the coating liquid flowability was excellent. In addition, shear force measurement for measuring the shear strength and breaking strength, which are physical strengths, of the pen core for the applicator for comparison of the present invention and the pen core for the applicator for comparison (same shape, size, porosity) When compared under the same conditions using a device and a breaking strength measuring device, it was confirmed that the strength was about three times higher in shear strength and about three times higher in breaking strength.
In addition, when writing on the characters, when the appearance of the other side was visually confirmed through the visible part during writing, the visibility was sufficient and easy to see, and writing was performed while reading the characters written in the writing direction. We were able to.

Furthermore, the applicator of Example 1 is set in an automatic writing device, and according to JIS S6037, a straight line is drawn on a high-quality paper at a writing angle of 65 °, a writing load of 1 N, a speed of 7 cm / s, and a distance of 100 m. When the state was visually confirmed, it was found that the pen core 10 for applicator had good writability, no blurring of drawn lines, and a good ink flow rate.

[Example 2]
In Example 1, polypropylene powder having an average particle size of 5 μm (melting point 160° C.) and polypropylene fibers having a fineness of 3 dtex and an average fiber length of 1 mm (melting point 160° C.) were used as the granular thermoplastic resin.
80% by mass of the granular thermoplastic resin and 20% by mass of the fibrous thermoplastic resin are kneaded and fired in the same manner as in Example 1, except that the firing temperature is 155 ° C. and the firing time is 60 minutes to form a sintered body. A pen core 10 for applicator (porosity of 60%) was obtained.
In the applicator according to Example 1 using the obtained pen core 10 for applicator, even if the material of the pen core for applicator is changed, the same effect as in Example 1 can be exhibited. confirmed.

The pen core for applicator of the present invention can be used for underline markers, felt-tip pens, pens for writing boards, etc., as long as it is a writing instrument, and as for applicators, it can be used as a cosmetic liquid applicator, a correction liquid applicator, and a chemical liquid. It can be suitably used for applicators, coating liquid applicators, and the like.

REFERENCE SIGNS LIST 10 applicator pen core 20 barrel 21 rear barrel 25 front barrel 30 application liquid occlusion body 40 holder 50 cap

Claims (3)

A pen core for an applicator, comprising: a granular thermoplastic resin having an average particle diameter of 10 μm or more and 300 μm or less; and the same material as the granular thermoplastic resin having a fineness of 1 to 100 dtex and an average fiber length A pen core for an applicator comprising a sintered body obtained by sintering a fibrous thermoplastic resin having a diameter of 0.1 to 2 mm and forming the whole into a substantially U-shaped shape. A pen core for an applicator, comprising: a granular thermoplastic resin having an average particle diameter of 10 μm or more and 300 μm or less; and the same material as the granular thermoplastic resin having a fineness of 1 to 100 dtex and an average fiber length A pen core for an applicator, comprising a sintered body obtained by sintering a fibrous thermoplastic resin having a diameter of 0.1 to 2 mm, and a porosity of the sintered body being 45 to 65%. The pen core for an applicator according to claim 1 or 2 is used, and the pen core for an applicator is attached to a holder through a shaft containing ink for a writing instrument, and a thermoplastic elastomer is attached to the outer surface or the rear end of the shaft. An applicator characterized in that it is formed in a part, and the writing instrument ink is a thermochromic ink.

Images