WO2024056217A1

WO2024056217A1 - Pen tip

Info

Publication number: WO2024056217A1
Application number: PCT/EP2023/063378
Authority: WO
Inventors: Kathy Fernande Odette VUILLAUME; Vinod Hiru TAMBE; Dinesh Madhukar TALEKAR; Xueyong CHENG; Sudhir Kanaiyalal BANIA
Original assignee: Societe Bic; Bic Cello (India) Private Ltd.
Priority date: 2022-09-12
Filing date: 2023-05-17
Publication date: 2024-03-21

Abstract

A writing tip (10) comprises a tubular writing tip body (100) comprising longitudinal axis (x), a distal end (110), a writing orifice (130) at the distal end (110), and a distal end face (140) extending at the distal end (110) and surrounding the writing orifice (130). The writing tip (10) further comprises a writing ball (200) comprising a writing ball diameter (d1). A distal end face angle (α), measured between a first plane (p1) defined by the distal end (110) and the distal end face (140), is between 5° to 14°, and a ratio of the ball support diameter (d2) and the writing ball diameter (d1) is larger than 0,80.

Description

PEN TIP

This application claims benefit from Indian patent application IN202211051962, filed on 12- Sep-2022, its content being incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to a writing tip, a writing tip system, a writing instrument, and a method of assembling a writing instrument.

BACKGROUND

Writing instruments, e.g., like a ballpoint pen, comprise a writing tip with a writing ball and can be used to apply a writing ink (e.g., an aqueous ink) to a writing surface. During a writing operation, writing ink is supplied to a writing orifice at a distal end of the writing tip and may surround the writing ball. When the writing ball is moved on the writing surface during a user’s writing operation, the writing ball may rotate and dispense writing ink onto the writing surface.

It may be important for a user to experience a high degree of smoothness when writing on a writing surface with the writing instrument. Smoothness characteristics may include scratching, pressure, gliding, cushioning, and/or ink flow. Scratching, for example, may be caused by the contact of a body of the writing tip or other components than the writing ball with the writing surface. Furthermore, it is important to the user that a writing instrument (almost) keeps the same level of performance over its lifetime, e.g., consistent line width. In addition to smoothness and level of performance, it is desirable to have a writing tip which may reduce or prevent ink bleed-through (i.e., ink that may be visible on the back of a writing surface after a writing operation, additionally depends on type of paper), clogging of the writing tip by paper fibers, blobbing (i.e., a random drop of ink on the writing surface during a writing operation), dotting (i.e., a drop of ink on the writing surface which can occur especially at the ends or tight curves of written letters) or gooping (i.e., an accumulation of ink on the outside of the writing ball or tip after a writing operation). However, existing writing instruments may not have a writing tip that provides the user with an improved sense of smoothness during a writing operation while reducing or preventing ink bleed-through, clogging of the writing tip, blobbing, dotting and/or gooping. Thus, the object of the present disclosure is to provide a writing tip which provides improved performance during a writing operation of a user.

SUMMARY

The present disclosure relates to a writing tip as defined in claim 1, a writing tip system as defined in claim 11, a writing instrument as defined in claim 12, and a method of assembling a writing instrument as defined in claim 13. The dependent claims depict advantageous embodiments of the present disclosure.

Based on various testing and validation, a writing tip has been developed that solves the object of the present disclosure and meets the targeted requirements. According to a first aspect of the present disclosure, a writing tip comprises a tubular writing tip body. The writing tip body comprises a longitudinal axis, a distal end, a writing orifice at the distal end, and a distal end face extending at the distal end and surrounding the writing orifice. Furthermore, the writing tip comprises a writing ball comprising a writing ball diameter, and the writing tip body comprises a ball support in the writing orifice, wherein the writing ball is rotatably arranged in the ball support. The ball support comprises a lower ball support section having a curved shape. The ball support defines a ball support diameter, measured in a radial direction at an upper edge of the lower ball support section. A distal end face angle, measured between a first plane defined by the distal end and the distal end face, is between 5° to 14°, and a ratio of the ball support diameter and the writing ball diameter is larger than 0,80. Thereby, smoothness during a writing operation can be improved while reducing or preventing clogging of the writing orifice, ink bleed-through a writing surface, blobbing, dotting and/or gooping. Furthermore, the performance of the writing tip can be improved and maintained (as best as possible) during its lifetime.

In embodiments, the distal end face angle may be between 6° to 11°, more specifically between 7° to 10°, in particular 9°. The distal end face angle of 9° may be a preferred angle that may lead to increased smoothness during a writing operation while further reducing clogging and/or gooping of the writing tip. More specifically, clogging may be reduced due to a lower intake of paper fibers in the writing tip during a writing operation. The ball support diameter may be larger than 0,56 mm. In embodiments, a ratio of the ball support diameter and the ball diameter may be between about 0,857 and about 0,914, more specifically between about 0,871 and about 0,907, in particular between about 0,874 and about 0,906. In embodiments, the ball support diameter may be between 0,600 mm and 0,640 mm, more specifically between 0,610 mm and 0,635 mm, in particular between 0,612 mm and 0,634 mm. In a preferred embodiment, the ball support diameter may be 0,614 mm, or the ball support diameter may be 0,632 mm. Together with the distal end face angle, particularly of 9° as defined above, smoothness during a user’s writing operation can be improved, while clogging of the writing orifice of the writing tip, blobbing, dotting, gooping of the writing tip and/or ink bleed- through the writing surface can be reduced or prevented.

The longitudinal axis may extend in the longitudinal direction of the writing tip body, and the radial direction may be perpendicular to the longitudinal axis. In embodiments, the distal end face may comprise a planar shape. The distal end face may be inclined inwardly the writing tip body and towards the longitudinal axis.

The ball support may comprise an upper ball support section having a curved shape. The writing tip body may comprise a proximal end opposite the distal end. Starting from the distal end in the direction of the longitudinal axis towards the proximal end, the writing tip body may comprise the upper ball support section followed by the lower ball support section. In embodiments, viewed from the distal end towards the proximal end in the direction of the longitudinal axis, the lower ball support section may comprise a convexly curved shape. Additionally or alternatively, viewed from the distal end towards the proximal end in the direction of the longitudinal axis, the upper ball support section may comprise at least partially a concavely curved shape.

In embodiments, the writing tip body may comprise a capillary extending from the proximal end to the writing orifice. The capillary may comprise a first capillary section and a second capillary section, more specifically wherein the first capillary section may be arranged between the ball support and the second capillary section. The first capillary section may comprise a first capillary section diameter and the second capillary section may comprise a second capillary section diameter, both measured in radial direction between respective inner circumferential surfaces. In embodiments, the first capillary section diameter may be smaller than the second capillary section diameter. The first capillary section diameter may be between 0,35 mm and 0,50 mm, more specifically between 0,40 mm and 0,45 mm, in particular 0,42 mm. An increased difference between the first capillary section diameter and the ball support diameter as defined above may lead to an improved ink flow through the writing tip. In embodiments, a combination of the defined first capillary section diameter together with the values and/or ratios for the ball support diameter and distal end face angle as defined above may lead to an improved ink flow through the writing tip while reducing or preventing blobbing, gooping and/or ink bleed-through. In addition, dotting may be reduced or prevented.

In embodiments, the writing tip body may comprise at least one ink channel, extending through the first capillary section substantially parallel to the direction of the longitudinal axis. The at least one ink channel may comprise an ink channel width, measured parallel to a tangential direction with respect to the longitudinal axis. In embodiments, the ink channel width may be between 0,10 mm and 0,15 mm, more specifically between 0,11 mm and 0,13 mm, in particular 0,12 mm. The at least one ink channel may comprise an ink channel diameter, measured in radial direction to an outer extent of the at least one ink channel. In embodiments, the ink channel diameter may be larger than the ball support diameter. In embodiments, a ratio of the ink channel diameter and the ball diameter may be between about 0,929 and about 1,000, more specifically between about 0,957 and about 0,971, in particular about 0,966. The ink channel diameter may be between 0,650 mm and 0,700 mm, more specifically between 0,670 mm and 0,680 mm, in particular 0,676 mm. In an embodiment, the writing tip body may comprise five ink channels uniformly distributed by an ink channel angle on an inner circumferential surface of the first capillary section.

In embodiments, the writing tip body may comprise an ink distribution section between the upper ball support section and the lower ball support section in the direction of the longitudinal axis. In an embodiment, the at least one ink channel may fluidly connect the ink distribution section and the first capillary section and/or the second capillary section. The ink distribution section may comprise an ink distribution section diameter, measured in the radial direction at a position where the ink distribution section has a maximum diameter. In an embodiment, ink distribution section diameter may be larger than the ball support diameter. In embodiments, the ink distribution section diameter may be between 0,750 mm and 0,765 mm, more specifically between 0,755 mm and 0,760 mm, in particular 0,758 mm. In embodiments, a ratio of the ink distribution section diameter and the ball diameter may be between about 1,071 and about 1,093, more specifically between about 1,079 and 1,086, in particular about 1,083. In embodiments, the ink distribution section may comprise a first tapered portion extending from the upper edge of the lower ball support section towards the position where the ink distribution section has a maximum diameter. More specifically, the first tapered portion may extend from the upper edge of the lower ball support section to the ink distribution section diameter. A first tapered portion angle, measured between the longitudinal axis and the first tapered portion, may be between about 40° and 50°, more specifically between about 43° and 47°, in particular 45 °. In embodiments, the ink distribution section may comprise a second tapered portion extending from the first tapered portion to a lower edge of the upper ball support section.

In embodiments, the ink distribution section may comprise a maximum diameter distance, measured parallel to the longitudinal axis between the position where the ink distribution section comprises a maximum diameter and the first plane. A ratio of the maximum diameter distance to the ball diameter may be between about 0,264 and about 0,314, more specifically about 0,274 and about 0,286, in particular about 0,280. In embodiments, a maximum diameter distance may be between 0,185 mm and 0,220 mm, more specifically between 0,192 mm und 0,200 mm, in particular 0,196 mm. In a preferred embodiment, the writing tip may comprise a first tapered portion angle of 45° and a maximum diameter distance of 0,196 mm. The combination of the parameters for first tapered portion angle, the distal end face angle and the maximum diameter distance as defined above may lead to increased smoothness during a writing operation while reducing or preventing clogging of the writing tip, blobbing, gooping and/or ink bleed through. In addition, dotting may be reduced or prevented.

The geometry of the ink distribution section, more specifically the parameter values of the ink distribution section diameter, the first tapered portion angle, the maximum diameter distance and the number of ink channels as defined above may define how ink spreads around (and lays down on) the writing ball in the ink distribution section when the writing ball rotates during a writing operation. With the combination of parameter values as defined above for ink channels, ink distribution section diameter, maximum diameter distance, first tapered portion angle and the defined ink channel diameter, an ink lay down on the writing ball (and in turn on the writing surface) can be improved. This can also have an effect on inner friction that may occur between the writing ball and the ball support (in particular the upper ball support section and/or the lower ball support section). Together with a distal end face angle of 9°, the writing tip may lead to increased smoothness during a writing operation while further reducing clogging, ink bleed- through, blobbing and/or gooping. The combination of the parameter values for the first capillary section diameter and the ball support diameter as defined above together with the first tapered portion angle as defined above may lead to an improved ink flow through the writing tip, resulting in reduced or prevented blobbing, gooping and/or ink bleed-through. Furthermore, dotting may be reduced or prevented.

In embodiments, a ball support gap, measured between the upper ball support section and the writing ball in the radial direction, may be between 20 pm and 26 pm, more specifically between 22 pm and 24 pm, in particular 23 pm. Due to the support ball gap as defined above, a rotation of the writing ball within the ball support may be ensured. Furthermore, cushioning (or dampening) of ink in the ball gap may lead to increased smoothness during a writing operation. Less contact (and thus reduced friction) of the writing ball with the walls of the ball support during a writing operation can lead to a faster writing experience and better control of the writing instrument for the user.

In embodiments, the writing tip body may comprise a first outer circumferential section extending from the distal end, more specifically from the distal end face, towards the proximal end, wherein the first outer circumferential section may be inclined with respect to the longitudinal axis. More specifically, the first outer circumferential section may comprise a planar shape and/or may, viewed from the distal end towards the proximal end, extend away from the longitudinal axis. In embodiments, a first outer circumferential section inclination angle, measured between the first plane and the first section, may be larger than 65°, more specifically larger than 69°, in particular 70°.

In embodiments, a writing ball protrusion distance, measured in the direction of the longitudinal axis between the first plane and an outer circumferential writing ball surface, may be between 0,240 mm and 0,255 mm, more specifically between 0,245 mm and 0,250 mm, in particular 0,248 mm. The combination of the writing ball protrusion distance and the first outer circumferential section inclination angle as defined above can increase smoothness during a writing operation by ensuring that, over a wide range of a user’ s writing angle, only the writing ball is in contact with the writing surface, but not other components of the writing tip, such as the writing tip body. According to a second aspect of the present disclosure, a writing tip system comprises a writing tip according to the first aspect of the present disclosure as defined above, and a cartridge configured to store a writing ink. The cartridge is coupled to a proximal end of the writing tip body.

In embodiments, the writing orifice may be in fluid communication with the cartridge, more specifically via a capillary extending through the writing tip body between the proximal end and the writing orifice. The writing tip system may further comprise writing ink stored in the cartridge, wherein the writing tip may be configured to apply ink onto a writing surface.

According to a third aspect of the present disclosure, a writing instrument comprises a tubular main body and a writing tip system according to the second aspect of the present disclosure as defined above. The tubular main body is coupled to the writing tip system.

In embodiments, the tubular main body may comprise a recess, and the cartridge and/or the writing tip may be at least partially inserted in the recess.

In embodiments, the writing tip system may be coupled to the tubular main body via a coupling member, which may be releasably coupled to the tubular main body and configured to retain the writing tip system in the tubular main body.

The writing instrument may further comprise at least one cap connectable to the tubular main body at a distal end of the main body. The at least one cap may be configured to be secured on the main body such that the writing tip may be covered by the cap.

In embodiments, the writing instrument may be a pen, more specifically a ballpoint pen.

According to a fourth aspect of the present disclosure, a method of assembling a writing instrument is provided. The method may comprise the steps of: a) providing a writing tip according to the first aspect of the present disclosure as defined above, a cartridge storing a writing ink, and a tubular main body; b) assembling the writing tip to the cartridge thereby forming a writing tip system; and c) coupling the writing tip system to the tubular main body. In an embodiment, the method may further comprise providing at least one cap, and securing the cap on the main body such that the writing tip may be covered by the cap.

In embodiments, coupling the writing tip system to the tubular body may comprise inserting the cartridge and/or the writing tip of the writing tip system at least partially into the tubular main body, and releasably coupling the writing tip system to the tubular main body.

In other embodiments, coupling the writing tip system to the tubular main body may comprise: a) providing a tubular coupling member, b) inserting the writing tip and/or the cartridge at least partially into the coupling member such that a distal end of the writing tip protrudes at least partially from the coupling member, c) inserting the cartridge and/or the writing tip at least partially into the tubular main body, and d) coupling the coupling member to the tubular main body, thereby releasably attaching the writing tip system to the tubular main body.

BRIEF DESCRIPTION OF THE DRAWINGS

Other characteristics will be apparent from the accompanying drawings, which form a part of this disclosure. The drawings are intended to further explain the present disclosure and to enable a person skilled in the art to practice it. However, the drawings are intended as non-limiting examples. Common reference numerals on different figures indicate like or similar features.

Figs. 1A to 1C are schematic views of a writing instrument and a writing tip system comprising a writing tip according to the present disclosure;

Fig. 2A is a more detailed schematic view of the writing tip according to the first aspect of the present disclosure;

Fig. 2B is a schematic cutaway side view of the writing tip, wherein the writing tip shown in Fig. 2A is cut along the longitudinal axis (x);

Figs. 3A and 3B are more detailed schematic cutaway views of the writing tip shown in Figs. 2A and 2B;

Fig. 3C is a schematic cutaway view of the writing tip shown in Fig. 3 A and 3B, cut at section A-A. DETAILED DESCRIPTION

Embodiments of the writing tip, the writing tip system, the writing instrument, and the method of assembling a writing instrument according to the present disclosure will be described in reference to the drawings as follows.

Figs. 1A to 1C are schematic views of a writing instrument 1 and a writing tip system comprising a writing tip 10 according to the present disclosure. As shown, the writing instrument 1, the writing tip system and the writing tip 10 comprise a longitudinal axis x, which extends in a longitudinal direction of the respective components. A radial direction r extends from and perpendicular to the longitudinal axis x.

The writing instrument 1 comprises a tubular main body 30 and a writing tip system comprising the writing tip 10 as defined in detail below. The tubular main body 30 is coupled to the writing tip system. The writing instrument 1 may be a handheld writing instrument for dispensing a writing ink, e.g., an aqueous ink, on a writing surface. In embodiments, the writing instrument 1 may be a pen, more specifically a ballpoint pen. As shown, e.g., in Fig. 1C, the writing instrument 1 may be moved onto a writing surface 60 (e.g., paper) during a writing operation of a user. A writing angle a may be defined between a vertical axis z, which is perpendicular to a plane defined by the writing surface 60, and the longitudinal axis x, when the writing instrument 1 is moved onto the writing surface 60. The writing angle a can vary depending on the hand position of the writing instrument 1 by the user on the writing surface in a writing operation.

Fig. 2A is a more detailed schematic view of the writing tip 10 according to an aspect of the present disclosure. Fig. 2B is a schematic cutaway side view of the writing tip 10, wherein the writing tip 10 shown in Fig. 2A is cut along the longitudinal axis x. The writing tip 10 comprises a tubular writing tip body 100 comprising the longitudinal axis x, which extends in the longitudinal direction of the writing tip body 100 and/or through a geometric center of the writing tip body 100. Furthermore, the writing tip body 100 comprises a distal end 110 and a proximal end 120 opposite the distal end 110 (i.e., on an opposite side of the writing tip body 100). The distal end 110 may be defined as the end furthest from the user's hand during a writing operation. In other words, the distal end 110 may be defined as the end of the writing tip body 100 that is closest to the writing surface 60 during a writing operation. Again, in other words, the distal end 110 may be the end of the writing tip body 100 furthest from the main body 30 when the writing tip 10 is coupled to the main body 30. The writing tip body 100 may further comprise a writing orifice 130 at the distal end 110 through which ink may be applied to the writing surface 60 when the writing tip 10 is moved onto the writing surface 60. Referring to Fig. 2B, the writing tip body 100 comprises a capillary 160 extending through the writing tip body 100 between the proximal end 120 and the writing orifice 130, more specifically in the direction of the longitudinal axis x. The present disclosure describes various effects associated with a writing operation, the writing tip 10, and the writing surface 60. “Blobbing” may be defined as a random drop of ink on the writing surface 60 during a writing operation of a user. “Gooping” may be defined as an accumulation of ink on the outside of a writing ball 200 of the writing tip 10 and/or on the writing tip 10 (e.g., on a part of the writing tip body 100) subsequent to a writing operation. “Clogging” of the writing orifice 130 may occur due to an accumulation of paper fibers in the writing orifice 130 subsequent to one or more writing operations, particularly between writing ball 200 and writing tip body 100. “Dotting” may be defined as a drop or drops of ink on the writing surface 60 which can occur especially at the ends or tight curves of written letters. “Ink bleed-through” may be defined as an accumulation of ink on a writing surface 60 that occurs during a writing operation, and which may be visible on a back side of a writing surface 60 subsequent to a writing operation. The extent of ink bleed-through may additionally depend on a type and characteristics of the writing surface 60, such as a specific type of paper of a particular thickness. Ink bleed-through may be the result of dotting or blobbing.

As shown, e.g., in Fig. IB, the writing tip system comprises the writing tip 10, which will be described in detail below. The writing tip system further comprises a cartridge 20 which is configured to store a writing ink. The cartridge 20 is coupled to the proximal end 120 of the writing tip body 100. In embodiments, the cartridge 20 may be releasably coupled to the proximal end 120 of the writing tip body 100. In still other embodiments, the cartridge 20 may be permanently coupled to the proximal end 120 of the writing body 100. The coupling between the proximal end 120 and the cartridge 20 may be fluid tight. The writing orifice 130 of the writing tip body 100 may be in fluid communication with the cartridge, more specifically via the capillary 160. The writing tip system may further comprise writing ink stored in the cartridge 20, wherein the writing tip 10 may be configured to apply writing onto a writing surface 60. In other words, during a writing operation, the writing ink may be supplied to the writing orifice 130 from the cartridge 20 via the capillary 160. Referring to Fig. 1A, the tubular main body 30 may comprise a recess, wherein the cartridge 20 and/or the writing tip 10 is at least partially inserted in the recess (not shown). In embodiments, the writing tip system may be coupled to the tubular main body 30 via a coupling member 40, which may releasably coupled to the tubular main body 30 and configured to retain the writing tip system in the tubular main body 30. As shown, e.g., in Fig. 1A, the writing instrument 1 may further comprise at least one cap 50 connectable to the tubular main body 30 at a distal end of the main body 30. The at least one cap 50 may be configured to be secured on the main body 30 such that the writing tip 10 is covered by the cap 50. In embodiments, the at least one cap may comprise a clip (not shown) to attach the writing instrument 1 to a suitable surface.

Figs. 3 A and 3B are more detailed schematic cutaway views of the writing tip 10 shown in Figs. 2 A and 2B. The writing tip 10 comprises a distal end face 140 extending at the distal end 110 and surrounding the writing orifice 130. As shown, e.g., in Fig. 3 A, the writing tip 10 comprises a writing ball 200 which defines a writing ball diameter dl . The writing tip body 100 comprises a ball support 300 in the writing orifice 130, wherein the writing ball 200 is rotatably arranged in the ball support 300. The ball support 300 comprises a lower ball support section 310 having a curved shape. Furthermore, the ball support 300 comprises an upper ball support section 320 having a curved shape. The curved shape of the lower ball support section 310 and/or the curved shape of the upper ball support section 320 may at least partially extend parallel to an outer contour, in particular an outer circumferential writing ball surface 210, of the writing ball 200. The upper ball support section 310 may be distanced to the lower ball support section 320 in the direction of the longitudinal axis x. Starting from the distal end 110 in the direction of the longitudinal axis x towards the proximal end 120, the writing tip body 100 comprises the upper ball support section 320 followed by the lower ball support section 310. Viewed from the distal end 110 towards the proximal end 120 in the direction of the longitudinal axis x, the lower ball support section 310 may comprise a convexly curved shape. Viewed from the distal end 110 towards the proximal end 120 in the direction of the longitudinal axis x, the upper ball support section 310 may comprise at least partially a concavely curved shape. The upper ball support section 310 may thus be configured to retain the writing ball 200 in the ball support 300, more specifically in the writing orifice 130. In other words, the writing ball 200 may be retained in the ball support 300 in such a way that it is prevented from moving out of the writing tip body 100 in the direction of the longitudinal axis x. The lower ball support section 310 may define a lower edge and an upper edge 311, wherein the upper edge 311 of the lower ball support section 310 is located more proximal to the distal end 110 in the direction of the longitudinal axis x than the lower edge of the lower ball support section 310. The upper ball support section 320 may define a lower edge 321 and an upper edge, wherein the upper edge of the upper ball support section 320 is located more proximal to the distal end 110 in the direction of the longitudinal axis x than the lower edge 321 of the upper ball support section 320.

Referring to Figs. 3 A and 3B, the ball support 300 defines a ball support diameter d2, measured in radial direction r at the upper edge 311 of the lower ball support section 310. A ratio of the ball support diameter d2 and the writing ball diameter dl is larger than 0,80 (i.e., d2/d 1 > 0,80). In embodiments, a ratio of the ball support diameter d2 and the ball diameter dl may be between about 0,857 and about 0,914, more specifically between about 0,871 and about 0,907, in particular between about 0,874 and about 0,906. The ball support diameter d2 may be larger than 0,56 mm. Thereby, dotting, gooping and/or blobbing of the writing tip 10 during a writing operation can be reduced or prevented. In embodiments, the ball support diameter d2 may be between 0,600 mm and 0,640 mm, more specifically between 0,610 mm and 0,635 mm, in particular between 0,612 mm and 0,634 mm. In an embodiment, the ball support diameter d2 may be between 0,610 mm and 0,620 mm, more specifically between 0,612 mm and 0,616 mm. In a preferred embodiment, the ball support diameter d2 may be 0,614 mm. In other embodiments, the ball support diameter may be between 0,625 mm and 0,640 mm, more specifically between 0,630 mm and 0,635 mm. In another preferred embodiment, the ball support diameter d2 may be 0,632 mm.

Referring to Figs. 3 A and 3B, the writing tip body 100 comprises a first outer circumferential section 190 extending from the distal end 110 (and/or the distal end face 140) towards the proximal end 120. More specifically, viewed from the distal end 110 towards the proximal end 120, the first outer circumferential section 190 extends away from the longitudinal axis x (i.e., in the radial direction r). In the embodiments shown in the Figs., an outer diameter of the writing tip body 100 measured in the radial direction r at the distal end 110 may be smaller than an outer diameter of the writing tip body 100 measured in the radial direction r at the distal end 120. Thus, the writing tip body 100, more specifically an outer circumferential surface of the writing tip body 100, may widen from the distal end 110 towards the proximal end 120. As shown in Figs. 3 A and 3B, the first outer circumferential section 190 is inclined, more specifically inclined outwardly, with respect to the longitudinal axis x. In the embodiment shown in Figs. 3 A and 3B, the first outer circumferential section 190 comprises a planar shape. A first outer circumferential section inclination angle 6 is defined between the first plane pl and the first outer circumferential section 190. In preferred embodiments, the first outer circumferential section inclination angle 6 may be larger than 65°, more specifically larger than 69°, in particular 70°. The above-mentioned values for inclination angle 6 may lead to increased smoothness during a writing operation.

As shown, e.g., in Figs. 3A and 3B, the distal end face 140 extends at the distal end 110 and surrounds the writing orifice 130. In other words, the distal end face 140 extends between the upper ball support section 320 and the first outer circumferential section 190 of the writing tip body 100, wherein the outer circumferential section 190 extends from the distal end 110 towards the proximal end 120 in the direction of the longitudinal axis x. The distal end 110 can be defined by a circumferential line, extending on the tubular writing tip body 100 between the distal end face 140 and the first outer circumferential section 190. However, in other embodiments (not shown in the Figs.), the distal end 110 may be defined by a circumferential line, extending on the tubular writing tip body 100 between the distal end face 140 and the upper ball support section 320.

The distal end 110 defines a first plane pl, which extends perpendicular to the longitudinal axis x. In embodiments, the first plane pl may extend parallel to a second plane defined by the proximal end 120. The distal end face 140 may comprise a planar shape. The distal end face 140 is inclined inwardly into the writing tip body 100 and extends from the distal end 110 and/or the first outer circumferential section 190 towards the longitudinal axis x. The expression “inclined inwardly” means that the distal end face 140 substantially extends towards a geometric center of the writing tip body 100. In other words, starting from the distal end 110 (and/or the first outer circumferential section 190), the distal end face 140 extends radially (i.e., in the radial direction r) towards the longitudinal axis x and axially (i.e., in the direction of the longitudinal axis x) towards the proximal end 120 or the geometric center of the writing tip body 100. However, in other embodiments (not shown in the Figs.), the distal end face 140 may be inclined outwardly the writing tip body 100. The expression “inclined outwardly” may mean that, starting from the first outer circumferential section 190, the distal end face 140 may extend away axially (i.e., in the direction of the longitudinal axis x) from a geometric center of the writing tip body 100 in the direction of the longitudinal axis x, and radially (i.e., in the radial direction r) towards the longitudinal axis x. A distal end face angle a, measured between the first plane pl defined by the distal end 110 and the distal end face 140, is between 5° to 14°. Together with the ball support diameter d2 as defined above, smoothness during a writing operation can be improved (due to decreased friction with a writing surface 60) while clogging of the writing orifice of the writing tip 10 with paper fibers, ink bleed-through a writing surface 60, blobbing, dotting and/or gooping of the writing tip 10 can be reduced or prevented. Based on the parameter values (i.e., concrete values or ranges) as defined above, improved performance of the writing tip 10 can be achieved and an improved balance between smoothness, and blobbing and/or dotting, can be achieved. In preferred embodiments, the distal end face angle a may be between 6° to 11°, more specifically between 7° to 10°, in particular 9°. In a preferred embodiment, the distal end face angle a is 9° and the ball support diameter is 0,632 mm or 0,614 mm.

As shown in Figs. 2B, 3 A and 3B, and as described above, the writing tip body 100 comprises a capillary 160 extending from the proximal end 120 to the writing orifice 130. The capillary 160 comprises a first capillary section 161 and a second capillary section 162. More specifically, the first capillary section 161 is arranged between the ball support 300 and the second capillary section 162. In other words, the second capillary section 162 is arranged between the first capillary section 161 and the proximal end 120. The lower ball support section 310 may be arranged at an upper end of the first capillary section 161. The first capillary section 160 comprises a first capillary section diameter cl and the second capillary section 162 comprises a second capillary section diameter c2, both measured in radial direction r between respective inner circumferential surfaces of the first capillary section 161 and the second capillary section 162. The first capillary section diameter cl is smaller than the second capillary section diameter c2. In embodiments, the first capillary section diameter cl may be between 0,35 mm and 0,50 mm, more specifically between 0,40 mm and 0,45 mm, in particular 0,42 mm. The first capillary section diameter cl and/or the second capillary section diameter c2 (together with the at least one ink channel) may determine the amount of ink flow from the cartridge 20 into the writing tip 10. An increased difference between the first capillary section diameter cl and the ball support diameter d2 as defined above may lead to an improved ink flow through the writing tip, resulting in reduced or prevented blobbing, dotting, gooping and/or ink bleed-through. Fig. 3C is a schematic cutaway view of the writing tip 10 shown in Fig. 3A and 3B, cut at section A-A. As shown in Figs. 3A to 3C, the writing tip body 100 comprises at least one ink channel 170, extending through the first capillary section 161 substantially parallel to the direction of the longitudinal axis x. More specifically, the at least one ink channel 170 may be provided as a groove on the inner circumferential surface of the first capillary section 161 and extending in the direction of the longitudinal axis x. In embodiments, the writing tip body 100 may comprise two, three, four, five, six or more ink channels 170. The ink channels 170 may be uniformly distributed by an ink channel angle P on an inner circumferential surface of the first capillary section 161. In a preferred embodiment as shown in Fig. 3C, the writing tip body 100 comprises five ink channels 170a-e uniformly distributed by an ink channel angle P on an inner circumferential surface of the first capillary section 161. In another preferred embodiment, the writing tip body 100 comprises six ink channels 170 uniformly distributed by an ink channel angle P on an inner circumferential surface of the first capillary section 161 (not shown in the Figs.).

The at least one ink channel 170 may comprise an ink channel width wl, measured parallel to a tangential direction with respect to the longitudinal axis x. The ink channel width wl may be between 0,10 mm and 0,15 mm, more specifically between 0,11 mm and 0,13 mm, in particular 0,12 mm. The width wl may be measured proximal a bottom of the at least one ink channel 170, viewed in the radial direction r. In embodiments, the at least one ink channel 170 may comprise a conical shape in the radial direction r. Starting from width wl at the bottom of the at least one ink channel 170, the width wl may at least partially decrease in the radial direction r towards the longitudinal axis x (not shown in the Figs.).

The at least one ink channel 170 comprises an ink channel diameter d3, measured in radial direction r to an outer extent of the at least one ink channel 170. More specifically, the ink channel diameter d3 is larger than the ball support diameter d2. In embodiments, a ratio of the ink channel diameter d3 and the ball diameter dl is between about 0,929 and about 1,000, more specifically between about 0,957 and about 0,971, in particular about 0,966. In preferred embodiments, the ink channel diameter d3 may be between 0,650 mm and 0,700 mm, more specifically between 0,670 mm and 0,680 mm, in particular 0,676 mm.

In a preferred embodiment, the distal end face angle a is 9°, the ball support diameter is 0,632 mm or 0,614 mm, and the ink channel diameter d3 is 0,676 mm. With these parameters, smoothness during a writing operation can be improved while clogging of the writing orifice of the writing tip 10, ink bleed-through a writing surface 60, blobbing, dotting and/or gooping of the writing tip 10 can be reduced or prevented. In other words, based on the parameter values defined above, improved performance of the writing tip 10 can be achieved.

Referring to Figs. 3 A and 3B, the writing tip body 100 comprises an ink distribution section 150 between the upper ball support section 320 and the lower ball support section 310 in the direction of the longitudinal axis x. The at least one ink channel 170 as defined above fluidly connects the ink distribution section 150 and the first capillary section 161 and/or the second capillary section 162. Due to the ink channel diameter d3, which is larger than the ball support diameter d2, ink flowing through the capillary 160, more specifically the first capillary section 161, can enter the ink distribution section 150 and spread around the writing ball 200. The ink distribution section 150 comprises an ink distribution section diameter d4, measured in the radial direction r at a position where the ink distribution section 150 has a maximum diameter. As shown, the ink distribution section diameter d4 is larger than the ball support diameter d2. In embodiments, a ratio of the ink distribution section diameter d4 and the ball diameter dl may be between about 1,071 and about 1,093, more specifically between about 1,079 and 1,086, in particular about 1,083. In preferred embodiments, the ink distribution section diameter d4 may be between 0,750 mm and 0,765 mm, more specifically between 0,755 mm and 0,760 mm, in particular 0,758 mm.

In the embodiments shown in Figs. 3 A and 3B, the ink distribution section 150 comprises a first tapered portion 151 extending from the upper edge 311 of the lower ball support section 310 towards (or to) the position where the ink distribution section 150 has a maximum diameter, more specifically to the ink distribution section diameter d4. In other words, the first tapered portion 151 extends from the upper edge 311 of the lower ball support section 310 towards (or to) a position where the ink distribution section 150 comprises the ink distribution section diameter d4. A first tapered portion angle y is defined between the longitudinal axis x and the first tapered portion 151. The first tapered portion angle y may be between about 40° and 50°, more specifically between about 43° and 47°, in particular 45 °. Alternatively, in embodiments, the first tapered portion angle may be measured between opposing sides of the first tapered portion 151. In this case, a double first tapered portion angle (i.e., a double first tapered portion angle 2y) may be between 80° and 100°, more specifically about 86° and 94°, in particular 90°. The ink distribution section 150 comprises a second tapered portion 152 extending from the first tapered portion 151 (i.e., from the position where the ink distribution section 150 has a maximum diameter) to the lower edge 321 of the upper ball support section 320. The combination of the parameter values for the first capillary section diameter cl and the ball support diameter d2 as defined above together with the first tapered portion angle y as defined above may lead to an improved ink flow through the writing tip 10, resulting in reduced or prevented blobbing, dotting, gooping and/or ink bleed-through.

As shown in Fig. 3B, the ink distribution section 150 comprises a maximum diameter distance xl, measured parallel to the longitudinal axis x between the position where the ink distribution section 150 comprises a maximum diameter and the first plane pl. In embodiments, a ratio of the maximum diameter distance xl to the ball diameter dl may be between about 0,264 and about 0,314, more specifically about 0,274 and about 0,286, in particular about 0,280. In preferred embodiments, the maximum diameter distance xl may be between 0,185 mm and 0,220 mm, more specifically between 0,192 mm und 0,200 mm, in particular 0,196 mm. The maximum diameter distance xl and the first tapered portion angle y may correlate to provide a uniform ink lay down on the writing ball 200 in the ink distribution section 150. In other words, if the maximum diameter distance xl is increased, the first tapered portion angle y may also be increased. A preferred combination may be a maximum diameter distance xl of 0,196 mm and a first tapered portion angle y of 45°. Thereby, an ink flow through the writing tip 10 may be improved while reducing or avoiding dotting, blobbing and/or gooping.

The combination of the parameters for the first tapered portion angle, the distal end face angle and the maximum diameter distance as defined above may lead to increased smoothness during a writing operation while reducing or preventing clogging of the writing tip 10, dotting, blobbing, gooping and/or ink bleed through. With the combination of parameter values as defined above for ink channels 170, ink distribution section diameter d4, maximum diameter distance xl, first tapered portion angle y and/or the defined ink channel diameter d3, an ink lay down on the writing ball 200 (in particular ink spread around the writing ball 200; and in turn on the writing surface 60) can be improved. This can also have an effect on an inner friction that may occur between the writing ball 200 and the ball support 300 (in particular the upper ball support section 320 and/or the lower ball support section 310).

As shown in Fig. 3A, a ball support gap 330 is defined between the upper ball support section 320 and the writing ball 200 in the radial direction r. In embodiments, the ball support gap 330 may be between 20 pm and 26 pm, more specifically between 22 pm and 24 pm, in particular 23 pm. The ball gap 330 can vary during a writing operation, i.e. during contact of the writing ball 200 with the writing surface 60. However, the ball gap 330 allows that the writing ball 200 can rotate within the ball support 300 in response to a contact with the writing surface 60, and that ink, laid down in the ink distribution section 150 on the writing ball 200, can be applied to the writing surface 60. Furthermore, cushioning (or dampening) of ink in the ball gap 330 may lead to increased smoothness during a writing operation. Less contact (and thus reduced friction) of the writing ball 200 with the walls of the ball support 300 during a writing operation can lead to a faster writing experience and better control of the writing instrument 1 for the user.

As shown, e.g., in Fig. 3 A, a writing ball protrusion distance x2 may be defined in the direction of the longitudinal axis x between the first plane pl and an outer circumferential writing ball surface 210. In other words, the protrusion distance x2 may be the distance, the writing ball 200 protrudes over the distal end 110 in the direction of the longitudinal axis x and/or away from the writing tip body 100. In embodiments, the writing ball protrusion distance x2 may be between 0,240 mm and 0,255 mm, more specifically between 0,245 mm and 0,250 mm, in particular 0,248 mm. The writing ball protrusion distance x2 and first outer circumferential section inclination angle 6 effect the smoothness perception of a user performing a writing operation. These parameters can ensure that, even when a user operates the writing instrument 1 and/or the writing tip 10 in a writing angle a larger than 60° (measured between the longitudinal axis x and the vertical axis z as described above) there is only writing ball 200 contact with the writing surface 60 (i.e., no or less contact of other components/parts like the writing tip body 100 which may result in scratching). This can lead to increased smoothness during a writing operation and low or zero friction of the writing tip body 100 (or components other than the writing ball 200) on the writing surface 60.

Testing and validating of the writing tip 10 has shown the following combination of parameter values, resulting in highly improved performance of the writing tip 10 during a writing operation. Thereby, smoothness during a writing operation (and the perception of smoothness to a user) can be greatly increased while reducing or preventing clogging with fibers (e.g., paper fibers) of the writing orifice 130 of the writing tip 10, ink bleed-through the writing surface 60, dotting, blobbing and/or gooping of the writing tip 10. In the preferred embodiment, the distal end face angle a is 9°, the ball support diameter is 0,632 mm or 0,614 mm, the ink channel diameter d3 is 0,676 mm, and the first outer circumferential section inclination angle 6 is 70°. In addition, the writing ball protrusion distance x2 is 0,248 mm and the first capillary section diameter cl is 0,42 mm. Furthermore, the geometry of the ink distribution section 150, more specifically the parameter values of the ink distribution section diameter d4, the first tapered portion angle y, the maximum diameter distance xl and the number of ink channels define how ink spreads around (and lays down on) the writing ball 200 in the ink distribution section 150 when the writing ball 200 rotates during a writing operation. With the combination of five ink channels 170a-e, an ink distribution section diameter d4 of 0,758 mm, a maximum diameter distance xl of0,196 mm, a first tapered portion angle y of 45° and the above defined ink channel diameter d3 of 0,676 mm, an ink lay down on the writing ball 200 (and in turn on the writing surface 60) can be improved. This can also have an effect on inner friction that occurs between the writing ball 200 and the ball support 300 (in particular the upper ball support section 320 and/or the lower ball support section 310). More specifically, cushioning (or dampening) of ink in the ball gap 330 may lead to increased smoothness during a writing operation. Furthermore, the performance of the writing tip 10 can be improved by using a specific writing ink with defined properties such as viscosity and density, together with the parameter values defined above for the writing tip 10. In other words, the properties of the writing ink may be tailored to the writing tip 10 as defined above to improve the performance of the writing tip 10, in particular to maintain a level of performance and to increase smoothness while reducing or preventing clogging, blobbing, dotting, gooping and/or ink bleed-through.

According to a further aspect, a method of assembling a writing instrument 1 as defined above comprises the following steps of a) providing a writing tip 10 as described above, a cartridge 20 storing a writing ink, and a tubular main body 30, b) assembling the writing tip 10 to the cartridge 20 thereby forming the writing tip system as described above, and c) coupling the writing tip system to the tubular main body 30.

In embodiments, the method may further comprise providing at least one cap 50, and securing the cap on the main body 30 such that the writing tip 10 is covered by the cap 50.

In embodiments, coupling the writing tip system to the tubular body 30 may comprise inserting the cartridge 20 and/or the writing tip 10 at least partially into the tubular main body 30, and releasably coupling the writing tip system to the tubular main body 30. Alternatively, coupling the writing tip system to the tubular main body 30 may comprise the following steps of: a) providing a tubular coupling member 40, b) inserting the writing tip 10 and/or the cartridge 20 at least partially into the coupling member 40 such that a distal end of the writing tip 10 protrudes at least partially from the coupling member 40, c) inserting the cartridge 20 and/or the writing tip 10 at least partially into the tubular main body 30, and d) coupling the coupling member 40 to the tubular main body 30, thereby releasably attaching the writing tip system to the tubular main body 30.

Although the present invention has been described above and is defined in the attached claims, it should be understood that the invention may alternatively be defined in accordance with the following embodiments:

1. A writing tip (10), comprising: a tubular writing tip body (100) comprising longitudinal axis (x), a distal end (110), a writing orifice (130) at the distal end (110), and a distal end face (140) extending at the distal end (110) and surrounding the writing orifice (130), characterized in that a distal end face angle (a), measured between a first plane (pl) defined by the distal end (110) and the distal end face (140), is between 5° to 14°.

2. The writing tip (10) according to embodiment 1, further comprising a writing ball (200) comprising a writing ball diameter (dl), wherein the writing tip body (100) comprises a ball support (300) in the writing orifice (130) and wherein the writing ball (200) is rotatably arranged in the ball support (300).

3. The writing tip (10) according to embodiment 2, wherein the ball support (300) comprises a lower ball support section (310) having a curved shape, and wherein the ball support (300) defines a ball support diameter (d2), measured in a radial direction (r) at an upper edge (311) of the lower ball support section (310).

4. The writing tip (10) according to embodiment 3, wherein a ratio of the ball support diameter (d2) and the writing ball diameter (dl) is larger than 0,80.

5. The writing tip (10) according to any one of the preceding embodiments, wherein the distal end face angle (a) is between 6° to 11°, more specifically between 7° to 10°, in particular 9°.

6. The writing tip (10) according to any one of embodiments 3 to 5, wherein the ball support diameter (d2) is larger than 0,56 mm.

7. The writing tip (10) according to any one of embodiments 3 to 6, wherein a ratio of the ball support diameter (d2) and the ball diameter (dl) is between about 0,857 and about 0,914, more specifically between about 0,871 and about 0,907, in particular between about 0,874 and about 0,906. The writing tip (10) according to any one of embodiments 3 to 7, wherein the ball support diameter (d2) is between 0,600 mm and 0,640 mm, more specifically between 0,610 mm and 0,635 mm, in particular between 0,612 mm and 0,634 mm. The writing tip (10) according to any one of embodiments 3 to 8, wherein the ball support diameter (d2) is 0,614 mm, or, wherein the ball support diameter (d2) is 0,632 mm. The writing tip (10) according to any one of the preceding embodiments, wherein the distal end face (140) comprises a planar shape. The writing tip (10) according to any one of the preceding embodiments, wherein the longitudinal axis (x) extends in the longitudinal direction of the writing tip body (100), and wherein the radial direction (r) is perpendicular to the longitudinal axis (x). The writing tip (10) according to any one of the preceding embodiments, wherein the distal end face (140) is inclined inwardly into the writing tip body (100) and towards the longitudinal axis (x). The writing tip (10) according to any one of embodiments 2 to 12, wherein the ball support (300) comprises an upper ball support section (320) having a curved shape. The writing tip (10) according to any one of the preceding embodiments, wherein the writing tip body (100) comprises a proximal end (120) opposite the distal end (110). The writing tip (10) according to embodiment 14, when dependent on embodiments 3 and 13, wherein, starting from the distal end (110) in the direction of the longitudinal axis (x) towards the proximal end (120), the writing tip body (100) comprises the upper ball support section (320) followed by the lower ball support section (310). 16. The writing tip (10) according to embodiment 14 or embodiment 15, when dependent on embodiment 3, wherein, viewed from the distal end (110) towards the proximal end (120) in the direction of the longitudinal axis (x), the lower ball support section (310) comprises a convexly curved shape.

17. The writing tip (10) according to any one of embodiments 14 to 16, when dependent on embodiment 13, wherein, viewed from the distal end (110) towards the proximal end (120) in the direction of the longitudinal axis (x), the upper ball support section (310) comprises at least partially a concavely curved shape.

18. The writing tip (10) according to any one of embodiments 14 to 17, wherein the writing tip body (100) comprises a capillary (160) extending from the proximal end (120) to the writing orifice (130).

19. The writing tip (10) according to embodiment 18, when dependent on embodiment 2, wherein the capillary (160) comprises a first capillary section (161) and a second capillary section (162), more specifically wherein the first capillary section (161) is arranged between the ball support (300) and the second capillary section (162).

20. The writing tip (10) according to embodiment 19, wherein the first capillary section (160) comprises a first capillary section diameter (cl) and the second capillary section (162) comprises a second capillary section diameter (c2), both measured in radial direction (r) between respective inner circumferential surfaces, wherein the first capillary section diameter (cl) is smaller than the second capillary section diameter (c2).

21. The writing tip (10) according to embodiment 20, wherein the first capillary section diameter (cl) is between 0,35 mm and 0,50 mm, more specifically between 0,40 mm and 0,45 mm, in particular 0,42 mm.

22. The writing tip (10) according to any one of embodiments 19 to 21, wherein the writing tip body (100) comprises at least one ink channel (170), extending through the first capillary section (161) substantially parallel to the direction of the longitudinal axis (x). 23. The writing tip (10) according to embodiment 22, wherein the at least one ink channel (170) comprises an ink channel width (wl), measured parallel to a tangential direction with respect to the longitudinal axis (x), which is between 0,10 mm and 0,15 mm, more specifically between 0,11 mm and 0,13 mm, in particular 0,12 mm.

24. The writing tip (10) according to embodiment 22 or embodiment 23, when dependent on embodiment 3, wherein the at least one ink channel (170) comprises an ink channel diameter (d3), measured in radial direction (r) to an outer extent of the at least one ink channel (170), wherein the ink channel diameter (d3) is larger than the ball support diameter (d2).

25. The writing tip (10) according to embodiment 24, when dependent on embodiment 2, wherein a ratio of the ink channel diameter (d3) and the ball diameter (dl) is between about 0,929 and about 1,000, more specifically between about 0,957 and about 0,971, in particular about 0,966.

26. The writing tip (10) according to embodiment 24 or embodiment 25, wherein the ink channel diameter (d3) is between 0,650 mm and 0,700 mm, more specifically between 0,670 mm and 0,680 mm, in particular 0,676 mm.

27. The writing tip (10) according to any one of embodiments 22 to 26, wherein the writing tip body (100) comprises five ink channels (170a-e) uniformly distributed by an ink channel angle (P) on an inner circumferential surface of the first capillary section (161).

28. The writing tip (10) according to any one of embodiments 13 to 27, when dependent on embodiment 3, wherein the writing tip body (100) comprises an ink distribution section (150) between the upper ball support section (320) and the lower ball support section (310) in the direction of the longitudinal axis (x).

29. The writing tip (10) according to embodiment 28, when dependent on any one of embodiments 22 to 27, wherein the at least one ink channel (170) fluidly connects the ink distribution section (150) and the first capillary section (161) and/or the second capillary section (162). The writing tip (10) according to embodiment 28 or embodiment 29, when dependent on embodiment 3, wherein the ink distribution section (150) comprises an ink distribution section diameter (d4), measured in the radial direction (r) at a position where the ink distribution section (150) has a maximum diameter, which is larger than the ball support diameter (d2). The writing tip (10) according to embodiment 30, wherein the ink distribution section diameter (d4) is between 0,750 mm and 0,765 mm, more specifically between 0,755 mm and 0,760 mm, in particular 0,758 mm. The writing tip (10) according to embodiment 30 or embodiment 30, when dependent on embodiment 2, wherein a ratio of the ink distribution section diameter (d4) and the ball diameter (dl) is between about 1,071 and about 1,093, more specifically between about 1,079 and 1,086, in particular about 1,083. The writing tip (10) according to any one of embodiments 30 to 33, when dependent on embodiment 3, wherein the ink distribution section (150) comprises a first tapered portion (151) extending from the upper edge (311) of the lower ball support section (310) towards the position where the ink distribution section (150) has a maximum diameter, more specifically to the ink distribution section diameter (d4). The writing tip (10) according to embodiment 30, wherein a first tapered portion angle (y), measured between the longitudinal axis (x) and the first tapered portion (151), is between about 40° and 50°, more specifically between about 43° and 47°, in particular 45°. The writing tip (10) according to embodiment 33 or embodiment 34, when dependent in embodiment 13, wherein the ink distribution section (150) comprises a second tapered portion (152) extending from the first tapered portion (151) to a lower edge (321) of the upper ball support section (320). The writing tip (10) according to any one of embodiments 28 to 35, wherein the ink distribution section (150) comprises a maximum diameter distance (xl), measured parallel to the longitudinal axis (x) between the position where the ink distribution section (150) comprises a maximum diameter and the first plane (pl). The writing tip (10) according to embodiment 36, when dependent on embodiment 2, wherein a ratio of the maximum diameter distance (xl) to the ball diameter (dl) is between about 0,264 and about 0,314, more specifically about 0,274 and about 0,286, in particular about 0,280. The writing tip (10) according to embodiment 36 or embodiment 37, wherein the maximum diameter distance (xl) is between 0,185 mm and 0,220 mm, more specifically between 0,192 mm und 0,200 mm, in particular 0,196 mm. The writing tip (10) according to any one of embodiments 13 to 38, when dependent on embodiment 2, wherein a ball support gap (330), measured between the upper ball support section (320) and the writing ball (200) in the radial direction (r), is between 20 pm and 26 pm, more specifically between 22 pm and 24 pm, in particular 23 pm. The writing tip (10) according to any one of embodiments 14 to 39, wherein the writing tip body (100) comprises a first outer circumferential section (190) extending from the distal end (110) towards the proximal end (120), wherein the first outer circumferential section (190) is inclined with respect to the longitudinal axis (x), more specifically wherein the first outer circumferential section (190) comprises a planar shape. The writing tip (10) according to embodiment 40, wherein a first outer circumferential section inclination angle (6), measured between the first plane (pl) and the first outer circumferential section (190), is larger than 65°, more specifically larger than 69°, in particular 70°. The writing tip (10) according to any one of the preceding embodiments, wherein a writing ball protrusion distance (x2), measured in the direction of the longitudinal axis (x) between the first plane (pl) and an outer circumferential writing ball surface (210) of the writing ball (200), is between 0,240 mm and 0,255 mm, more specifically between 0,245 mm and 0,250 mm, in particular 0,248 mm. 43. A writing tip system, comprising: a writing tip (10) according to any one of the preceding embodiments, and a cartridge (20) configured to store a writing ink, wherein the cartridge (20) is coupled to a proximal end (120) of the writing tip body (100).

44. The writing tip system according to embodiment 43, wherein the writing orifice (130) is in fluid communication with the cartridge (20), more specifically via a capillary (160) extending through the writing tip body (100) between the proximal end (120) and the writing orifice (130).

45. The writing tip system according to embodiment 43 or embodiment 44, further comprising writing ink stored in the cartridge (20), wherein the writing tip (10) is configured to apply ink onto a writing surface (60).

46. A writing instrument (1), comprising: a tubular main body (30), and a writing tip system according to any one of embodiments 43 to 45, wherein the tubular main body (30) is coupled to the writing tip system.

47. The writing instrument (1) according to embodiment 46, wherein the tubular main body (30) comprises a recess, and wherein the cartridge (20) and/or the writing tip (10) is at least partially inserted in the recess.

48. The writing instrument (1) according to embodiment 46 or embodiment 47, wherein the writing tip system is coupled to the tubular main body (30) via a coupling member (40), which is releasably coupled to the tubular main body (30) and configured to retain the writing tip system in the tubular main body (30).

49. The writing instrument (1) according to any one of embodiments 46 to 48, further comprising at least one cap (50) connectable to the tubular main body (30) at a distal end of the main body (30). 50. The writing instrument (1) according to embodiment 49, wherein the at least one cap (50) is configured to be secured on the main body (30) such that the writing tip (10) is covered by the cap (50).

51. The writing instrument (1) according to any one of embodiments 46 to 50, wherein the writing instrument (1) is a pen, more specifically a ballpoint pen.

52. Method of assembling a writing instrument (1), comprising: providing a writing tip (10) according to any one of embodiments 1 to 42, a cartridge (20) storing a writing ink, and a tubular main body (30), assembling the writing tip (10) to the cartridge (20) thereby forming a writing tip system, and coupling the writing tip system to the tubular main body (30).

53. The method according to embodiment 52, further comprising: providing at least one cap (50), and securing the cap on the main body (30) such that the writing tip (10) is covered by the cap (50).

54. The method according to embodiment 52 or embodiment 53, wherein coupling the writing tip system to the tubular body (30) comprises inserting the cartridge (20) and/or the writing tip (10) at least partially into the tubular main body (30), and releasably coupling the writing tip system to the tubular main body (30).

55. The method according to embodiment 52 or embodiment 53, wherein coupling the writing tip system to the tubular main body (30) comprises: providing a tubular coupling member (40), inserting the writing tip (10) and/or the cartridge (20) at least partially into the coupling member (40) such that a distal end of the writing tip (10) protrudes at least partially from the coupling member (40), inserting the cartridge (20) and/or the writing tip (10) at least partially into the tubular main body (30), and coupling the coupling member (40) to the tubular main body (30), thereby releasably attaching the writing tip system to the tubular main body (30). REFERENCE NUMERALS

1 writing instrument 300 ball support

10 writing tip 310 lower ball support section 20 cartridge 311 upper edge of lower ball support

30 tubular main body 30 section

40 coupling member 320 upper ball support section

50 cap 321 lower edge of upper ball support

60 writing surface section 100 tubular writing tip body 330 ball support gap

110 distal end 35 x longitudinal axis

120 proximal end r radial direction

130 writing orifice dl writing ball diameter

140 distal end face d2 ball support diameter 150 ink distribution section d3 ink channel diameter

151 first tapered portion 40 d4 ink distribution section diameter

152 second tapered portion cl first capillary section diameter

160 capillary c2 second capillary section diameter

161 first capillary section wl ink channel width 162 second capillary section a distal end face angle

170 ink channel 45 P ink channel angle

170a-e ink channels y first tapered portion angle

190 first outer circumferential section 6 first outer circumferential section

200 writing ball inclination angle 210 outer circumferential writing ball 8 writing angle surface

Claims

CLAIMS A writing tip (10), comprising: a tubular writing tip body (100) comprising longitudinal axis (x), a distal end (110), a writing orifice (130) at the distal end (110), and a distal end face (140) extending at the distal end (110) and surrounding the writing orifice (130), and a writing ball (200) comprising a writing ball diameter (dl), wherein the writing tip body (100) comprises a ball support (300) in the writing orifice (130) and wherein the writing ball (200) is rotatably arranged in the ball support (300), wherein the ball support (300) comprises a lower ball support section (310) having a curved shape, and wherein the ball support (300) defines a ball support diameter (d2), measured in a radial direction (r) at an upper edge (311) of the lower ball support section (310), characterized in that a distal end face angle (a), measured between a first plane (pl) defined by the distal end (110) and the distal end face (140), is between 5° to 14°, and in that a ratio of the ball support diameter (d2) and the writing ball diameter (dl) is larger than 0,80. The writing tip (10) according to claim 1, wherein the distal end face angle (a) is between 6° to 11°, more specifically between 7° to 10°, in particular 9°. The writing tip (10) according to claim 1 or claim 2, wherein the ball support diameter (d2) is between 0,600 mm and 0,640 mm, more specifically between 0,610 mm and 0,635 mm, in particular between 0,612 mm and 0,634 mm. The writing tip (10) according to any one of the preceding claims, wherein the writing tip body (100) comprises a proximal end (120) opposite the distal end (110), and wherein the writing tip body (100) comprises a capillary (160) extending from the proximal end (120) to the writing orifice (130). The writing tip (10) according to claim 4, wherein the capillary (160) comprises a first capillary section (161) and a second capillary section (162), more specifically wherein the first capillary section (161) is arranged between the ball support (300) and the second capillary section (162), and wherein the writing tip body (100) comprises at least one ink channel (170), extending through the first capillary section (161) substantially parallel to the direction of the longitudinal axis (x).

6. The writing tip (10) according to claim 5, wherein the at least one ink channel (170) comprises an ink channel diameter (d3), measured in radial direction (r) to an outer extent of the at least one ink channel (170), wherein the ink channel diameter (d3) is larger than the ball support diameter (d2).

7. The writing tip (10) according to claim 6, wherein the ink channel diameter (d3) is between 0,650 mm and 0,700 mm, more specifically between 0,670 mm and 0,680 mm, in particular 0,676 mm.

8. The writing tip (10) according to any one of the preceding claims, wherein the ball support (300) comprises an upper ball support section (320) having a curved shape, and wherein the writing tip body (100) comprises an ink distribution section (150) between the upper ball support section (320) and the lower ball support section (310) in the direction of the longitudinal axis (x), wherein the ink distribution section (150) comprises an ink distribution section diameter (d4), measured in radial direction (r) at a position where the ink distribution section (150) has a maximum diameter, which is larger than the ball support diameter (d2).

9. The writing tip (10) according to claim 8, wherein the ink distribution section (150) comprises a first tapered portion (151) extending from the upper edge (311) of the lower ball support section (310) towards the position where the ink distribution section (150) has a maximum diameter, more specifically to the ink distribution section diameter (d4), wherein a first tapered portion angle (y), measured between the longitudinal axis (x) and the first tapered portion (151), is between about 40° and 50°, more specifically between about 43° and 47°, in particular 45°.

10. The writing tip (10) according to any one of claims 4 to 9, wherein the writing tip body (100) comprises a first outer circumferential section (190) extending from the distal end (110) towards the proximal end (120), wherein a first outer circumferential section inclination angle (6), measured between the first plane (pl) and the first outer circumferential section (190), is larger than 65°, more specifically larger than 69°, in particular 70°. A writing tip system, comprising: a writing tip (10) according to any one of the preceding claims, and a cartridge (20) configured to store a writing ink, wherein the cartridge (20) is coupled to a proximal end (120) of the writing tip body (100). A writing instrument (1), comprising: a tubular main body (30), and a writing tip system according to claim 11, wherein the tubular main body (30) is coupled to the writing tip system. Method of assembling a writing instrument (1), comprising: providing a writing tip (10) according to any one of claims 1 to 10, a cartridge (20) storing a writing ink, and a tubular main body (30), assembling the writing tip (10) to the cartridge (20) thereby forming a writing tip system, and coupling the writing tip system to the tubular main body (30). The method according to claim 13, further comprising: providing at least one cap (50), and securing the cap on the main body (30) such that the writing tip (10) is covered by the cap (50). The method according to claim 13 or claim 14, wherein coupling the writing tip system to the tubular main body (30) comprises: providing a tubular coupling member (40), inserting the writing tip (10) and/or the cartridge (20) at least partially into the coupling member (40) such that a distal end of the writing tip (10) protrudes at least partially from the coupling member (40), inserting the cartridge (20) and/or the writing tip (10) at least partially into the tubular main body (30), and coupling the coupling member (40) to the tubular main body (30), thereby releasably attaching the writing tip system to the tubular main body (30).