JP4155660B2

JP4155660B2 - Marking pen and method for preventing crystal precipitation from pen core of marking pen

Info

Publication number: JP4155660B2
Application number: JP08943999A
Authority: JP
Inventors: 和弘小柳津; 秀永見
Original assignee: Mitsubishi Pencil Co Ltd
Current assignee: Mitsubishi Pencil Co Ltd
Priority date: 1999-03-30
Filing date: 1999-03-30
Publication date: 2008-09-24
Anticipated expiration: 2019-03-30
Also published as: JP2000280685A

Description

【０００１】
【発明の属する技術分野】
本発明は、インキを貯蔵するインキ貯蔵部を有する本体軸と、インキ貯蔵部からインキを吐出させるように本体軸の前端側に前方へ突出して装着されたペン芯と、ペン芯の前方突出部分を覆うように本体軸の前端側に着脱自在に装着されるキャップとが備えられたマーキングペン及びマーキングペンのペン芯からの結晶析出防止方法に関する。
【０００２】
【従来の技術】
マーキングペンには、インキを貯蔵するインキ貯蔵部を有する本体軸と、インキ貯蔵部からインキを吐出させるように本体軸の前端側に前方へ突出して装着されたペン芯と、ペン芯の前方突出部分を覆うように本体軸の前端側に着脱自在に装着されるキャップとが備えられている。
【０００３】
【発明が解決しようとする課題】
マーキングペンのペン芯の前方突出部分に浸透したインキは、本体軸の前端側にキャップを装着すると、キャップ外の空気との接触は防止されるが、キャップ内の空気との接触は防止されない。従って、低温（主に０°Ｃ前後以下）でのマーキングペンの保管時に、ペン芯からインキが結晶として析出する花咲が生じて、製品特性を著しく損なう場合がある。従来は、このようなペン芯からのインキの結晶析出（花咲）をインキ自体により防止するため、温度低下により溶解度が極端に低下する有効成分をインキへ添加することが制限されていた。
【０００４】
例えば、描線濃度の向上を目的としてインキの染料濃度を高くしたマーキングペンでは、低温保管時に、ペン芯から染料が結晶析出して、析出物の影響で所望の描線幅が得られず、また、析出物が黴と間違えられるなどの問題が発生する。また、耐乾燥性に優れた添加剤を含むインキを使用したマーキングペンでは、低温保管時に、ペン芯の先端のインキ吐出部分が結晶析出した添加剤により塞がれ、インキの吐出に支障をきたすなどの問題が発生する。従って、マーキングペンのインキの染料濃度を高くしたり、インキに耐乾燥性添加剤を添加することが制限されていた。
【０００５】
本発明は、このような問題に鑑み、マーキングペンのペン芯からのインキの結晶析出（花咲）を、ペン芯及びキャップの構造により防止し、インキ設計上の制限を緩和することができるマーキングペン及びマーキングペンのペン芯からの結晶析出防止方法を提供することを目的とする。
【０００６】
【課題を解決するための手段】
請求項１に記載の発明は、染料あるいは耐乾燥性に優れた添加剤を含むインキを貯蔵するインキ貯蔵部を有する本体軸と、
前記インキ貯蔵部からインキを吐出させるように前記本体軸の前端側に前方へ突出して装着されたペン芯と、
前記ペン芯の前方突出部分を覆うように前記本体軸の前端側に着脱自在に装着されるキャップとが備えられ、
前記ペン芯は、前端部及び後端部が露出して後端側から前端側へインキを浸透させる基質部と、前記基質部の外周を被覆して外周面へのインキの浸出を阻止し、その外周表面の研磨加工を行わない外皮部とを有し、
前記キャップの内側前端には、前記ペン芯の前記基質部の前端露出部分を被覆してインキを吸収する吸液部材が装着され、
前記ペン芯の前記外皮部と前記吸液部材とにより、前記ペン芯の前記基質部中のインキと前記キャップ内の空気との接触を防止することを特徴とするマーキングペンである。
【０００７】
請求項１に記載の発明によれば、マーキングペンの低温保管時等の不使用時に、本体軸の前端側にペン芯を覆うキャップを装着すると、ペン芯の基質部がペン芯の外皮部と吸液部材とにより被覆されて、ペン芯の基質部に浸透したインキがキャップ内の空気と接触しないため、インキが結晶として析出する花咲を防止することができ、インキの結晶析出（花咲）による外観の悪化、運筆状態への悪影響を防止することができる。従って、ペン芯からのインキの結晶析出防止のためのインキ設計上の制限を緩和することができ、例えば、描線濃度の向上を目的として、インキの染料濃度を高くすることができ、また、耐乾燥性に優れた添加剤を添加することもできる。
【０００８】
また、請求項２に記載の発明においては、ペン芯の外皮部は、基質部を透視し得るように透明に、即ち、センターレス表面研磨加工等を行わずに形成されている。請求項２に記載の発明によれば、ペン芯の外皮部を透明に形成したため、マーキングペンの使用中に、ペン芯の基質部内に浸透したインキの色を外皮部と通して容易に判別することができる。
【０００９】
また、請求項３に記載の発明においては、ペン芯の外皮部の材質は、アクリル樹脂、ポリカーボネイト等の透明性の高い樹脂である。請求項３に記載の発明によれば、ペン芯の外皮部を好適に透明に形成することができる。
請求項４に記載の発明は、染料あるいは耐乾燥性に優れた添加剤を含むインキを貯蔵するインキ貯蔵部を有する本体軸と、
前記インキ貯蔵部からインキを吐出させるように前記本体軸の前端側に前方へ突出して装着されたペン芯と、
前記ペン芯の前方突出部分を覆うように前記本体軸の前端側に着脱自在に装着されるキャップとを備え、
前記ペン芯は、前端部及び後端部が露出して後端側から前端側へインキを浸透させる基質部と、前記基質部の外周を被覆して外周面へのインキの浸出を阻止し、その外周表面の研磨加工を行わない外皮部とを設け、
前記キャップの内側前端には、前記ペン芯の前記基質部の前端露出部分を被覆してインキを吸収する吸液部材を装着し、
前記ペン芯の前記外皮部と前記吸液部材とにより、前記ペン芯の前記基質部中のインキと前記キャップ内の空気との接触を防止することを特徴とするマーキングペンのペン芯からの結晶析出防止方法である。
【００１０】
【発明の実施の形態】
以下、図面を参照して本発明の実施の形態を説明する。図１は、本発明の実施の形態に係るマーキングペンの縦断面図である。
【００１１】
図１に示すように、本発明の実施の形態に係るマーキングペンには、インキを貯蔵するインキ貯蔵部１４を有する本体軸１０と、インキ貯蔵部１４からインキを吐出させるように本体軸１０の前端側に前方へ突出して装着されたペン芯（被覆ペン芯）２０と、ペン芯２０の前方突出部分を覆うように本体軸１０の前端側に着脱自在に装着されるキャップ３０とが備えられている。
【００１２】
本体軸１０は、前後方向に伸延した細長い円筒状に形成されており、本体軸１０の内周側のインキ貯蔵部１４には、中綿１６が収容され、中綿１６にインキが吸蔵されている。なお、インキ貯蔵部１４は、中綿１６を使用せずに、インキをそのまま貯留するタンク状（インキ直接貯留方式）にしてもよい。
【００１３】
そして、本体軸１０の前端側には、前側が縮経したテーパー円筒状の先軸部１２が設けられており、先軸部１２には、前後方向に伸延した円柱状（棒状）のペン芯２０が、前側部分を先軸部１２より前方に突出させると共に、後端部分をインキ貯蔵部１４の中綿１６に食い込ませるようにして装着されている。
【００１４】
ペン芯２０は、内周側の基質部２２と外周側の外皮部２４とが一体化された構造になっており、基質部２２は、前端部（インキ吐出部分）及び後端部（インキ吸入部分）が外皮部２４から露出して、後端側から前端側へインキを浸透させるようになっており、外皮部２４は、基質部２２の外周を被覆して、基質部２２から外周面へのインキの浸出を阻止するようになっている。
【００１５】
ペン芯２０の基質部２２と外皮部２４とは、同一の材料により同時に形成することができ、異なる材料により個別に形成することもできる。ペン芯２０の基質部２２と外皮部２４とを同一の材料により同時に形成する場合には、例えば、ポリアセタール樹脂をダイスにより押出成形して伸延させ、ダイスの形状により内周側に複雑な形状の毛細管を形成することによって、内周側を基質部２２とすることができる。
【００１６】
一方、ペン芯２０の基質部２２と外皮部２４とを異なる材料により個別に形成する場合には、例えば、基質部２２は、アクリル系繊維、ポリエステル系繊維等の合成繊維を集束し、合成樹脂系接着剤を含浸させて乾燥、固化させることによって形成する。そして、外皮部２４は、ポリエチレン、ポリプロピレン、ポリアセタール、塩化ビニール、アクリル、ポリカーボネイト等の合成樹脂により、基質部２２の外周を被覆するように形成する。
【００１７】
また、ペン芯２０の外皮部２４は、基質部２２に浸透したインキを透視し得るように、透明に形成されており、外皮部２４としては、アクリル樹脂、ポリカーボネイト等の透明性の高い樹脂が好ましい。また、ペン芯２０においては、外皮部２４の透明性を確保するため、外周表面のセンターレス研磨加工（棒状被研磨物の中心を決めずに複数の砥石で被研磨物を外周から包囲して外周表面を研磨する）を行わない。なお、通常のペン芯は、外径寸法調整のために外周表面のセンターレス研磨加工が施され、ペン芯の外周表面に無数の研磨痕が残る。
【００１８】
キャップ３０は、外周壁部３２と前壁部３４とからなる後端が開口した円筒状に形成されており、キャップ３０は、本体軸１０の前端側に着脱自在に装着されて、ペン芯２０の前方突出部分及び本体軸１０の先軸部１２を覆うようになっている。
【００１９】
そして、キャップ３０の前壁部３４の後面側（内面側）には、後端が開口した円筒状の吸液部材支持部３６が設けられており、吸液部材支持部３６には、インキを吸収する吸液部材４０が装着されており、吸液部材４０の後面は、吸液部材支持部３６の後端開口を介して露出するようになっている。なお、吸液部材支持部３６の後端開口の内周縁は、吸液部材４０の脱落防止のため、内周側に突出した鍔状に形成されている。
【００２０】
そして、キャップ３０を本体軸１０の前端側に装着すると、吸液部材４０の後面側にはペン芯２０の基質部２２の前端部（インキ吐出部分）が食い込む形で密着し、ペン芯２０の基質部２２の前端部は吸液部材４０により被覆されるようになっている。
【００２１】
吸液部材４０としては、例えば、繊維を束ねた芯、ウレタン、フェルト、焼結体等、インキを吸収する任意な材料が使用可能であるが、吸液部材４０は、ペン芯２０の強度、形状に対応した適度な硬さ、弾力性を有することが必要である。
【００２２】
このように構成されるマーキングペンの使用時には、本体軸１０のインキ貯蔵部１４のインキが、ペン芯２０の基質部２２の後端側から前端側に浸透して、基質部２２の前端部から吐出するが、ペン芯２０の外皮部２４が透明に形成されているので、基質部２２中のインキを透視することができ、使用者が、インキの色を容易に認識することができる。
【００２３】
そして、マーキングペンの低温保管時等の不使用時には、キャップ３０を本体軸１０の前端側に装着すると、ペン芯２０の基質部２２の前端部分が吸液部材４０に密着して被覆され、また、基質部２２の外周は外皮部２４により被覆されているので、ペン芯２０からインキが浸出してキャップ３０内の空気と接触して結晶として析出する花咲を防止することができる。従って、インキの結晶析出（花咲）による外観の悪化、運筆状態への悪影響を防止することができる。
【００２４】
また、上述のように、マーキングペンのペン芯２０からのインキの結晶析出（花咲）を、インキ自体ではなく、ペン芯２０及びキャップ３０の構造により防止することによって、インキ設計上の制限を緩和することができる。例えば、描線濃度の向上を目的として、インキの染料濃度を高くすることができ、また、耐乾燥性に優れた添加剤を添加することもできる。
【００２５】
なお、上述の実施の形態では、ペン芯が本体軸の前端側に設けられた場合について述べたが、２つのペン芯が本体軸の前後両端側に設けられた構造（ツイン型）にしてもよい。また、上述の実施の形態では、ペン芯の前方突出部分及び先軸部を覆うキャップが着脱自在に本体軸に装着される場合について述べたが、ペン芯の前方突出部分を覆う内キャップと、内キャップ及び先軸部を覆う外キャップとが装着されるようにしてもよい。
【００２６】
【実施例】
本発明に係る実施例１〜３のマーキングペンと、比較例１〜４のマーキングペンとについて、ペン芯、吸液部材、インキの仕様を表１に示す。なお、実施例１〜３のマーキングペンの具体的形状等は、上述の実施の形態（図１）と同様であり、また、比較例１〜４のマーキングペンの具体的形状等は、ペン芯、吸液部材を除いて、上述の実施の形態と同様である。
【００２７】
【表１】

【００２８】
本発明に係る実施例１〜３のマーキングペンと、比較例１〜４のマーキングペンとを、０°Ｃの恒温槽に横向きに保管し、３日後、７日後、１４日後に恒温槽から取り出して、ペン芯の結晶析出状態、運筆状態を試験した。試験結果を表２に示す。
【００２９】
【表２】

【００３０】
表２に示すように、本発明に係る実施例１〜３のマーキングペンでは、キャップ装着時に、ペン芯に浸透したインキがキャップ内の空気と非接触となるため、低温下に置かれた場合でも、インキ中の有効成分又は染料がペン芯の表面に析出することがなく、従って、外観を悪化させることがなく、また、運筆状態に悪影響を及ぼさない。
【００３１】
一方、比較例１のマーキングペンでは、ペン芯の先端部（前端部）及び側面部（外周部）共に結晶析出が著しく、運筆状態にも悪影響を及ぼしている。また、比較例２、３のマーキングペンでは、ペン芯の側面部からの結晶析出はないが、ペン芯の先端部からの結晶析出により運筆状態に悪影響がでている。また、比較例４のマーキングペンでは、ペン芯の先端部が吸液部材により被覆されるため、運筆への影響は見られないが、ペン芯側面部からの析出により外観の悪化を生じている。
【００３２】
また、実施例１、３のマーキングペンのペン芯について、センターレス表面研磨加工の実施品及び未実施品の対比確認を行ったが、センターレス表面研磨加工の実施品は、外皮部の表面が荒らされて白く見えるたため、基質部内のインキの視認性が悪く、一方、未実施品は、外皮部の透明性が確保されているため、基質部内のインキの判別が可能である。
【００３３】
【発明の効果】
請求項１に記載の発明によれば、マーキングペンの低温保管時等の不使用時に、本体軸の前端側にペン芯を覆うキャップを装着すると、ペン芯の基質部がペン芯の外皮部と吸液部材とにより被覆されて、ペン芯の基質部に浸透したインキがキャップ内の空気と接触しないため、インキが結晶として析出する花咲を防止することができ、インキの結晶析出（花咲）による外観の悪化、運筆状態への悪影響を防止することができる。また、ペン芯からのインキの結晶析出防止のためのインキ設計上の制限を緩和することができ、例えば、描線濃度の向上を目的として、インキの染料濃度を高くすることができ、また、耐乾燥性に優れた添加剤を添加することもできる。
【００３４】
また、請求項２に記載の発明によれば、ペン芯の外皮部をセンターレス表面研磨加工等を行わずに透明に形成したため、マーキングペンの使用中に、ペン芯の基質部内に浸透したインキの色を外皮部と通して容易に判別することができる。また、請求項３に記載の発明によれば、ペン芯の外皮部を好適に透明に形成することができる。
【図面の簡単な説明】
【図１】本発明の実施の形態に係るマーキングペンの縦断面図である。
【符号の説明】
１０本体軸
１２先軸部
１４インキ貯蔵部
１６中綿
２０ペン芯
２２基質部
２４外皮部
３０キャップ
３２外周壁部
３４前壁部
３６吸液部材支持部
４０吸液部材[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a main body shaft having an ink storage section for storing ink, a pen core that protrudes forward on the front end side of the main body shaft so as to eject ink from the ink storage section, and a forward protruding portion of the pen core The present invention relates to a marking pen provided with a cap that is detachably mounted on a front end side of a main body shaft so as to cover the surface of the main body shaft and a method for preventing crystal precipitation from the pen core of the marking pen .
[0002]
[Prior art]
The marking pen has a main body shaft having an ink storage section for storing ink, a pen core that protrudes forward on the front end side of the main body shaft so as to eject ink from the ink storage section, and a front protrusion of the pen core. A cap is detachably attached to the front end side of the main body shaft so as to cover the portion.
[0003]
[Problems to be solved by the invention]
If the ink penetrating into the front protruding portion of the pen core of the marking pen is attached to the front end side of the main body shaft, contact with the air outside the cap is prevented, but contact with the air inside the cap is not prevented. Accordingly, when the marking pen is stored at a low temperature (mainly around 0 ° C. or less), a flower blooms in which the ink precipitates as crystals from the pen core, which may significantly impair the product characteristics. Conventionally, in order to prevent such ink crystal precipitation (Hanazaki) from the pen core by the ink itself, it has been limited to add an active ingredient whose solubility is extremely lowered due to a temperature drop to the ink.
[0004]
For example, in a marking pen that increases the dye concentration of the ink for the purpose of improving the line density, the dye crystallizes out of the pen core during storage at low temperature, and the desired line width cannot be obtained due to the influence of the precipitate. Problems such as deposits being mistaken for soot occur. In addition, in marking pens that use inks containing additives with excellent drying resistance, the ink discharge part at the tip of the pen core is blocked by the crystallized additive during low-temperature storage, which may hinder ink discharge. Problems occur. Therefore, it has been restricted to increase the dye concentration of the marking pen ink or to add a drying resistance additive to the ink.
[0005]
In view of such a problem, the present invention prevents the ink crystal precipitation (Hanazaki) from the pen core of the marking pen by the structure of the pen core and the cap, and can ease restrictions on the ink design. Another object of the present invention is to provide a method for preventing crystal precipitation from a pen core of a marking pen .
[0006]
[Means for Solving the Problems]
The invention according to claim 1 is a main shaft having an ink storage section for storing ink containing an additive having excellent dye resistance or drying resistance ;
A pen core mounted to protrude forward on the front end side of the main body shaft so as to eject ink from the ink storage unit;
A cap that is detachably attached to the front end side of the main body shaft so as to cover the front protruding portion of the pen core,
The pen core, the front end portion and the rear end portion are exposed and the substrate portion that permeates ink from the rear end side to the front end side, and the outer periphery of the substrate portion is covered to prevent the ink from leaching to the outer peripheral surface , It has an outer skin portion that does not polish the outer peripheral surface ,
A liquid absorbing member that covers the front end exposed portion of the substrate portion of the pen core and absorbs ink is attached to the inner front end of the cap,
The marking pen is characterized in that contact between the ink in the substrate portion of the pen core and the air in the cap is prevented by the outer skin portion of the pen core and the liquid absorbing member.
[0007]
According to the first aspect of the present invention, when a cap that covers the pen core is attached to the front end side of the main body shaft when the marking pen is not used at low temperature storage or the like, the substrate portion of the pen core is separated from the outer skin portion of the pen core. The ink covered with the liquid absorbing member and penetrating into the substrate portion of the pen core does not come into contact with the air in the cap, so that it is possible to prevent the flower blooming in which the ink is precipitated as crystals, and by the ink crystal deposition (flower blooming) Deterioration of the appearance and adverse effects on the stroke state can be prevented. Accordingly, it is possible to relax restrictions on the ink design for preventing the precipitation of ink crystals from the pen core. For example, the ink dye density can be increased for the purpose of improving the line density, and An additive having excellent drying properties can also be added.
[0008]
In the invention described in claim 2, the outer skin portion of the pen core is formed transparent so that the substrate portion can be seen through, that is, without performing centerless surface polishing or the like. According to the second aspect of the present invention, since the outer skin portion of the pen core is formed transparently, the color of the ink that has penetrated into the substrate portion of the pen core is easily determined through the outer skin portion during use of the marking pen. be able to.
[0009]
In the invention described in claim 3, the material of the outer skin portion of the pen core is a highly transparent resin such as an acrylic resin or polycarbonate. According to invention of Claim 3, the outer skin part of a pen core can be formed suitably transparently.
The invention according to claim 4 is a main shaft having an ink storage section for storing ink containing an additive having excellent dye resistance or drying resistance;
A pen core mounted to protrude forward on the front end side of the main body shaft so as to eject ink from the ink storage unit;
A cap that is detachably attached to the front end side of the main body shaft so as to cover the front protruding portion of the pen core,
The pen core, the front end portion and the rear end portion are exposed and the substrate portion that permeates ink from the rear end side to the front end side, and the outer periphery of the substrate portion is covered to prevent the ink from leaching to the outer peripheral surface, Provide a skin part that does not polish the outer peripheral surface,
At the inner front end of the cap, a liquid absorbing member that covers the front end exposed part of the substrate part of the pen core and absorbs ink is attached,
A crystal from a pen core of a marking pen, which prevents contact between ink in the substrate portion of the pen core and air in the cap by the outer skin portion of the pen core and the liquid absorbing member. This is a precipitation prevention method.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view of a marking pen according to an embodiment of the present invention.
[0011]
As shown in FIG. 1, the marking pen according to the embodiment of the present invention includes a main body shaft 10 having an ink storage section 14 that stores ink, and a main shaft 10 that discharges ink from the ink storage section 14. A pen core (covered pen core) 20 that protrudes forward and attached to the front end side, and a cap 30 that is detachably attached to the front end side of the main body shaft 10 so as to cover the front protruding portion of the pen core 20 are provided. ing.
[0012]
The main body shaft 10 is formed in an elongated cylindrical shape extending in the front-rear direction, and the inner cotton storage 16 is accommodated in the ink storage portion 14 on the inner peripheral side of the main body shaft 10, and the ink is occluded in the inner cotton 16. The ink storage unit 14 may be in the form of a tank that stores ink as it is (ink direct storage system) without using the batting 16.
[0013]
The front end of the main body shaft 10 is provided with a tapered cylindrical front shaft portion 12 whose front side is contracted, and the front shaft portion 12 has a columnar (bar-shaped) pen core extending in the front-rear direction. 20 is mounted so that the front portion protrudes forward from the front shaft portion 12 and the rear end portion bites into the batting 16 of the ink storage portion 14.
[0014]
The pen core 20 has a structure in which an inner peripheral side substrate portion 22 and an outer peripheral side outer skin portion 24 are integrated. The substrate portion 22 has a front end portion (ink ejection portion) and a rear end portion (ink suction portion). Part) is exposed from the outer skin part 24 and allows the ink to permeate from the rear end side to the front end side. The outer skin part 24 covers the outer periphery of the substrate part 22 and extends from the substrate part 22 to the outer peripheral surface. The ink is prevented from leaching.
[0015]
The substrate portion 22 and the outer skin portion 24 of the pen core 20 can be formed simultaneously with the same material, or can be formed individually with different materials. In the case where the substrate portion 22 and the outer skin portion 24 of the pen core 20 are simultaneously formed of the same material, for example, polyacetal resin is extruded and extended by a die, and a complicated shape is formed on the inner peripheral side by the shape of the die. By forming a capillary tube, the inner peripheral side can be used as the substrate portion 22.
[0016]
On the other hand, when the substrate portion 22 and the outer skin portion 24 of the pen core 20 are individually formed of different materials, for example, the substrate portion 22 converges synthetic fibers such as acrylic fibers and polyester fibers to form a synthetic resin. It is formed by impregnating with a system adhesive and drying and solidifying. The outer skin portion 24 is formed so as to cover the outer periphery of the substrate portion 22 with a synthetic resin such as polyethylene, polypropylene, polyacetal, vinyl chloride, acrylic, and polycarbonate.
[0017]
Further, the outer skin portion 24 of the pen core 20 is formed to be transparent so that the ink that has permeated the substrate portion 22 can be seen through, and the outer skin portion 24 is made of a highly transparent resin such as acrylic resin or polycarbonate. preferable. Further, in the pen core 20, in order to ensure the transparency of the outer skin portion 24, centerless polishing of the outer peripheral surface (the polishing object is surrounded from the outer periphery with a plurality of grindstones without determining the center of the rod-shaped polishing object). The outer peripheral surface is not polished). In addition, the normal pen core is subjected to centerless polishing on the outer peripheral surface for adjusting the outer diameter, and innumerable polishing marks remain on the outer peripheral surface of the pen core.
[0018]
The cap 30 is formed in a cylindrical shape having an open rear end composed of an outer peripheral wall portion 32 and a front wall portion 34, and the cap 30 is detachably attached to the front end side of the main body shaft 10, and the pen core 20. The front protruding portion of the main body shaft 10 and the front shaft portion 12 of the main body shaft 10 are covered.
[0019]
A cylindrical liquid-absorbing member support portion 36 having an open rear end is provided on the rear surface side (inner surface side) of the front wall portion 34 of the cap 30, and ink is supplied to the liquid-absorbing member support portion 36. A liquid absorbing member 40 to be absorbed is mounted, and the rear surface of the liquid absorbing member 40 is exposed through the rear end opening of the liquid absorbing member support portion 36. The inner peripheral edge of the rear end opening of the liquid absorbing member support portion 36 is formed in a bowl shape protruding toward the inner peripheral side to prevent the liquid absorbing member 40 from falling off.
[0020]
When the cap 30 is attached to the front end side of the main body shaft 10, the front end portion (ink discharge portion) of the substrate portion 22 of the pen core 20 is in close contact with the rear surface side of the liquid absorbing member 40. The front end portion of the substrate portion 22 is covered with the liquid absorbing member 40.
[0021]
As the liquid absorbing member 40, for example, any material that absorbs ink, such as a fiber bundled core, urethane, felt, and sintered body, can be used. It is necessary to have appropriate hardness and elasticity corresponding to the shape.
[0022]
When the marking pen configured as described above is used, the ink in the ink storage unit 14 of the main body shaft 10 penetrates from the rear end side to the front end side of the substrate portion 22 of the pen core 20, and from the front end portion of the substrate portion 22. Although the outer cover 24 of the pen core 20 is formed transparently, the ink in the substrate 22 can be seen through, and the user can easily recognize the color of the ink.
[0023]
When the marking pen is not used at low temperature storage or the like, when the cap 30 is attached to the front end side of the main body shaft 10, the front end portion of the substrate portion 22 of the pen core 20 is in close contact with the liquid absorbing member 40, and Since the outer periphery of the substrate portion 22 is covered with the outer skin portion 24, it is possible to prevent flower blooms that are leached out of the pen core 20 and contact with the air in the cap 30 to precipitate as crystals. Accordingly, it is possible to prevent the deterioration of the appearance and the bad influence on the handwriting state due to the ink crystal precipitation (Hanazaki).
[0024]
In addition, as described above, ink crystal precipitation (flower bloom) from the pen core 20 of the marking pen is prevented not by the ink itself but by the structure of the pen core 20 and the cap 30, thereby relaxing the restrictions on the ink design. can do. For example, for the purpose of improving the drawn line density, the dye concentration of the ink can be increased, and an additive having excellent drying resistance can also be added.
[0025]
In the above-described embodiment, the case where the pen core is provided on the front end side of the main body shaft has been described. However, the structure (twin type) in which two pen cores are provided on both the front and rear end sides of the main body shaft is used. Good. Moreover, in the above-described embodiment, the case where the cap that covers the front protruding portion and the tip shaft portion of the pen core is detachably attached to the main body shaft has been described, but the inner cap that covers the front protruding portion of the pen core; You may make it mount | wear with the outer cap which covers an inner cap and a front-axis | shaft part.
[0026]
【Example】
Table 1 shows the specifications of the pen core, liquid-absorbing member, and ink for the marking pens of Examples 1 to 3 and the marking pens of Comparative Examples 1 to 4 according to the present invention. In addition, the specific shape etc. of the marking pen of Examples 1-3 are the same as that of the above-mentioned embodiment (FIG. 1), Moreover, the specific shape of the marking pen of Comparative Examples 1-4 is a pen core. Except for the liquid absorbing member, it is the same as the above embodiment.
[0027]
[Table 1]

[0028]
The marking pens of Examples 1 to 3 and the marking pens of Comparative Examples 1 to 4 according to the present invention are stored sideways in a thermostatic bath at 0 ° C., taken out from the thermostatic bath after 3, 7 and 14 days. The pen core crystal deposition state and the stroke state were tested. The test results are shown in Table 2.
[0029]
[Table 2]

[0030]
As shown in Table 2, in the marking pens of Examples 1 to 3 according to the present invention, when the cap is mounted, the ink that has penetrated the pen core is not in contact with the air in the cap, and therefore when placed under a low temperature. However, the active ingredient or the dye in the ink does not deposit on the surface of the pen core, and thus the appearance is not deteriorated, and the stroke state is not adversely affected.
[0031]
On the other hand, in the marking pen of Comparative Example 1, crystal precipitation is remarkable at both the tip end portion (front end portion) and the side surface portion (outer peripheral portion) of the pen core, which adversely affects the handwriting state. In the marking pens of Comparative Examples 2 and 3, there is no crystal precipitation from the side surface of the pen core, but the pendant state is adversely affected by crystal precipitation from the tip of the pen core. Further, in the marking pen of Comparative Example 4, since the tip of the pen core is covered with the liquid absorbing member, there is no influence on the brush stroke, but the appearance is deteriorated due to precipitation from the side surface of the pen core. .
[0032]
In addition, for the pen cores of the marking pens of Examples 1 and 3, the centerless surface polishing processed product and the unimplemented product were compared, but the centerless surface polishing processed product has a surface of the outer skin portion. Since it looks rough and white, the visibility of the ink in the substrate portion is poor. On the other hand, in the unimplemented product, the transparency of the outer skin portion is ensured, so that the ink in the substrate portion can be discriminated.
[0033]
【The invention's effect】
According to the first aspect of the present invention, when a cap that covers the pen core is attached to the front end side of the main body shaft when the marking pen is not used at low temperature storage or the like, the substrate portion of the pen core is separated from the outer skin portion of the pen core. The ink covered with the liquid absorbing member and penetrating into the substrate portion of the pen core does not come into contact with the air in the cap, so that it is possible to prevent the flower blooming in which the ink is precipitated as crystals, and by the ink crystal deposition (flower blooming) Deterioration of the appearance and adverse effects on the stroke state can be prevented. In addition, it is possible to relax restrictions on ink design to prevent ink crystal precipitation from the pen core. For example, the ink dye concentration can be increased for the purpose of improving the line density, and An additive having excellent drying properties can also be added.
[0034]
According to the second aspect of the present invention, since the outer skin portion of the pen core is formed transparent without performing centerless surface polishing or the like, the ink that has penetrated into the substrate portion of the pen core during use of the marking pen Can be easily discriminated through the skin part. Moreover, according to the invention of Claim 3, the outer skin part of a pen core can be formed suitably transparently.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a marking pen according to an embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Main body axis | shaft 12 Tip axis part 14 Ink storage part 16 Filling pad 20 Pen core 22 Substrate part 24 Outer part 30 Cap 32 Outer peripheral wall part 34 Front wall part 36 Liquid absorbing member support part 40 Liquid absorbing member

Claims

A main body shaft having an ink storage section for storing ink containing a dye or an additive excellent in drying resistance ;
A pen core mounted to protrude forward on the front end side of the main body shaft so as to eject ink from the ink storage unit;
A cap that is detachably attached to the front end side of the main body shaft so as to cover the front protruding portion of the pen core,
The pen core, the front end portion and the rear end portion are exposed and the substrate portion that permeates ink from the rear end side to the front end side, and the outer periphery of the substrate portion is covered to prevent the ink from leaching to the outer peripheral surface , It has an outer skin portion that does not polish the outer peripheral surface ,
The inner front end of the cap is mounted with a liquid absorbing member that covers the front end exposed portion of the substrate portion of the pen core and absorbs ink,
A marking pen characterized in that contact between the ink in the substrate portion of the pen core and the air in the cap is prevented by the outer skin portion of the pen core and the liquid absorbing member.

The marking pen according to claim 1, wherein the outer skin portion of the pen core is formed to be transparent so that the substrate portion can be seen through.

The marking pen according to claim 2, wherein a material of the outer skin portion of the pen core is a highly transparent resin such as an acrylic resin or polycarbonate.

A main body shaft having an ink storage section for storing ink containing a dye or an additive excellent in drying resistance;
  A pen core mounted to protrude forward on the front end side of the main body shaft so as to eject ink from the ink storage unit;
  A cap that is detachably attached to the front end side of the main body shaft so as to cover the front protruding portion of the pen core,
  The pen core has a substrate portion that exposes the front end portion and the rear end portion and allows ink to permeate from the rear end side to the front end side, and covers the outer periphery of the substrate portion to prevent ink from leaching to the outer peripheral surface, Provide a skin part that does not polish the outer peripheral surface,
  At the inner front end of the cap, a liquid absorbing member that covers the front end exposed part of the substrate part of the pen core and absorbs ink is attached,
  A crystal from a pen core of a marking pen, which prevents contact between the ink in the substrate portion of the pen core and the air in the cap by the outer skin portion of the pen core and the liquid absorbing member. Precipitation prevention method.