U.S. patent application number 12/576024 was filed with the patent office on 2010-03-25 for writing instrument.
This patent application is currently assigned to MITSUBISHI PENCIL KABUSHIKI KAISHA. Invention is credited to Takao Koyama.
Application Number | 20100074672 12/576024 |
Document ID | / |
Family ID | 29422412 |
Filed Date | 2010-03-25 |
United States Patent
Application |
20100074672 |
Kind Code |
A1 |
Koyama; Takao |
March 25, 2010 |
WRITING INSTRUMENT
Abstract
In a writing instrument in which an ink for a writing instrument
such as a water-based ink and an oil-based ink impregnated into an
ink occlusion body in a barrel is fed to a pen tip in a writing
part, in order to provide a writing instrument in which a sign of
exhausting the ink can readily and surely be detected, the above
writing instrument is provided with a structure in which the ink
impregnated into the ink occlusion body in the barrel is fed to the
pen tip in the writing part, wherein the ink impregnated into the
ink occlusion body described above is fed to the pen tip via an ink
guiding feed having visibility, and a sign of exhausting the ink
fed from the ink occlusion body is detected by visually observing
the ink guiding feed described above via a visible part formed in
the barrel.
Inventors: |
Koyama; Takao; (Fujioka-shi,
JP) |
Correspondence
Address: |
BUCHANAN, INGERSOLL & ROONEY PC
POST OFFICE BOX 1404
ALEXANDRIA
VA
22313-1404
US
|
Assignee: |
MITSUBISHI PENCIL KABUSHIKI
KAISHA
Shinagawa-ku
JP
|
Family ID: |
29422412 |
Appl. No.: |
12/576024 |
Filed: |
October 8, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10511304 |
Oct 15, 2004 |
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PCT/JP03/05952 |
May 13, 2003 |
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12576024 |
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Current U.S.
Class: |
401/198 |
Current CPC
Class: |
B43K 7/06 20130101; C09D
11/16 20130101; B43K 7/10 20130101; B43K 8/04 20130101; B43K 7/005
20130101; B43K 7/08 20130101; B43K 27/08 20130101; B43K 8/003
20130101 |
Class at
Publication: |
401/198 |
International
Class: |
B43K 8/06 20060101
B43K008/06 |
Foreign Application Data
Date |
Code |
Application Number |
May 14, 2002 |
JP |
2002-138517 |
May 14, 2002 |
JP |
2002-138518 |
Claims
1-20. (canceled)
21. A writing instrument comprising: an ink occlusion body disposed
in a barrel, the ink occlusion body including a capillary material
impregnated with ink; a pen tip including a capillary material
disposed in a writing part of the writing instrument, wherein the
ink impregnated in the ink occlusion body is fed to the pen tip via
an ink guiding feed; wherein ink flows from the capillary material
of said occlusion body by virtue of capillary force and ink flows
into the capillary material of said pen tip by virtue of capillary
force, said ink guiding feed lacking any capillary material
therewithin; wherein said ink guiding feed is tubular and has a
cross-sectional area of 0.5 to 20 mm.sup.2 such that it does not
have capillary force and said ink guiding feed is disposed within
the barrel between the ink occlusion body and the pen tip so as to
prevent outside air from flowing in when the ink occlusion body is
impregnated with ink, and allowing outside air to flow into the
barrel as ink in the ink occlusion body is depleted; and wherein
said ink guiding feed has visibility such that a sign of exhausting
the ink fed from the ink occlusion body to the pen tip is detected
by visually observing the empty ink guiding feed via a visible part
formed in the barrel.
22. A writing instrument of a twin type in which an ink impregnated
into an ink occlusion body in a barrel is fed to respective pen
tips in writing parts disposed at both sides of the barrel, wherein
the ink fed to either of the pen tips is fed to the pen tip via an
ink guiding feed having visibility, and a sign of exhausting the
ink fed from the ink occlusion body is detected by visually
observing the ink guiding feed described above via a visible part
formed in the barrel.
23. The writing instrument as described in claim 21, wherein the
ink impregnated into the ink occlusion body is fed to the ink
guiding feed having visibility via an inter-feeder.
24. The writing instrument as described in claim 22, wherein the
ink impregnated into the ink occlusion body is fed to the ink
guiding feed having visibility via an inter-feeder.
25. The writing instrument as described in claim 23, wherein the
inter-feeder is brought into contact with the inside of the ink
occlusion body in a length of 5% or more based on an overall length
of the ink occlusion body.
26. The writing instrument as described in claim 24, wherein the
inter-feeder is brought into contact with the inside of the ink
occlusion body in a length of 5% or more based on an overall length
of the ink occlusion body.
27. The writing instrument as described in claim 23, wherein the
inter-feeder has a cross-sectional area of 1 to 90% based on a
cross-sectional area of the ink occlusion body.
28. The writing instrument as described in claim 24, wherein the
inter-feeder has a cross-sectional area of 1 to 90% based on a
cross-sectional area of the ink occlusion body.
29. The writing instrument as described in claim 23, wherein the
inter-feeder has larger capillary force than that of the ink
occlusion body.
30. The writing instrument as described in claim 24, wherein the
inter-feeder has larger capillary force than that of the ink
occlusion body.
31. The writing instrument as described in claim 23, wherein the
inter-feeder has a cross-section structure comprising an inner
layer and an outer layer, and the outer layer has larger capillary
force than that of the inner layer.
32. The writing instrument as described in claim 24, wherein the
inter-feeder has a cross-section structure comprising an inner
layer and an outer layer, and the outer layer has larger capillary
force than that of the inner layer.
33. The writing instrument as described in claim 23, wherein the
ink fed to the ink guiding feed having visibility via the
inter-feeder is fed to the pen tip further via a pen tip
feeder.
34. The writing instrument as described in claim 24, wherein the
ink fed to the ink guiding feed having visibility via the
inter-feeder is fed to the pen tip further via a pen tip
feeder.
35. The writing instrument as described in claim 23, wherein the
inter-feeder comprises any one of a fiber bundle feed, porous
sintered body of resin particles and a sliver feed, and a passage
cross-sectional area for an ink flowing through the ink guiding
feed can substantially be controlled by providing the inter-feeder
with continuous passages while maintaining an apparent
cross-sectional area of the ink guiding feed.
36. The writing instrument as described in claim 24, wherein the
inter-feeder comprises any one of a fiber bundle feed, porous
sintered body of resin particles and a sliver feed, and a passage
cross-sectional area for an ink flowing through the ink guiding
feed can substantially be controlled by providing the inter-feeder
with continuous passages while maintaining an apparent
cross-sectional area of the ink guiding feed.
37. The writing instrument as described in claim 21, wherein a
surface of the ink guiding feed which is brought into contact with
the ink is formed of a material or the ink guiding feed itself is
formed of a material having a smaller surface tension than that of
the ink.
38. The writing instrument as described in claim 22, wherein a
material of a face of the ink guiding feed having visibility which
is brought into contact with the ink or a material of the ink
guiding feed itself has a smaller surface tension than that of the
ink.
39. The writing instrument as described in claim 21, wherein the
occlusion body has a distribution in capillary force such that it
is increased toward a pen tip side.
40. The writing instrument as described in claim 22, wherein the
occlusion body has a distribution in capillary force such that it
is increased toward a pen tip side.
41. The writing instrument as described in claim 21, wherein an
inner diameter of the barrel is narrower toward the pen tip
side.
42. The writing instrument as described in claim 22, wherein an
inner diameter of the barrel is narrower toward the pen tip
side.
43. The writing instrument as described in claim 21, wherein plural
ribs are formed in an axial direction on an inner wall of the pen
tip side of the barrel.
44. The writing instrument as described in claim 22, wherein plural
ribs are formed in an axial direction on an inner wall of the pen
tip side of the barrel.
45. The writing instrument as described in claim 21, wherein a
plurality of the ink guiding feeds having visibility is
provided.
46. The writing instrument as described in claim 22, wherein a
plurality of the ink guiding feeds having visibility is
provided.
47. The writing instrument as described in claim 21, wherein the
ink impregnated into the ink occlusion body is fed to the pen tip
through an ink-feeder in addition to the ink guiding feed having
visibility.
48. The writing instrument as described in claim 22, wherein the
ink impregnated into the ink occlusion body is fed to the pen tip
through an ink-feeder in addition to the ink guiding feed having
visibility.
49. The writing instrument as described in claim 21, wherein a
passage cross-sectional area for the ink flowing through the ink
guiding feed and flow resistance of the ink can substantially be
controlled by filling the ink guiding feed having visibility with a
fiber bundle feed or a porous sintered body of resin particles
which has a smaller surface tension than that of the ink and has a
color which is different from that of the ink while maintaining an
apparent cross-sectional area of the ink guiding feed.
50. The writing instrument as described in claim 22, wherein a
passage cross-sectional area for the ink flowing through the ink
guiding feed and flow resistance of the ink can substantially be
controlled by filling the ink guiding feed having visibility with a
fiber bundle feed or a porous sintered body of resin particles
which has a smaller surface tension than that of the ink and has a
color which is different from that of the ink while maintaining an
apparent cross-sectional area of the ink guiding feed.
51. The writing instrument as described in claim 21, wherein the
visible part in the barrel has a length of 1 mm or more and not
longer than an overall length of the writing instrument.
52. The writing instrument as described in claim 22, wherein the
visible part in the barrel has a length of 1 mm or more and not
longer than an overall length of the writing instrument.
53. The writing instrument as described in claim 21, wherein the
ink guiding feed has an ink passage cross-sectional area of
8.times.10.sup.-2 to 80 mm.sup.2.
54. The writing instrument as described in claim 22, wherein the
ink guiding feed has an ink passage cross-sectional area of
8.times.10.sup.-2 to 80 mm.sup.2.
55. The writing instrument as described in claim 21, wherein the
ink has a surface tension of 18 mN/or more at 25.degree. C.
56. The writing instrument as described in claim 22, wherein the
ink has a surface tension of 18 mN/or more at 25.degree. C.
57. The writing instrument as described in claim 21, wherein the
ink has a viscosity of 500 mPas or less at 25.degree. C.
58. The writing instrument as described in claim 22, wherein the
ink has a viscosity of 500 mPas or less at 25.degree. C.
59. A writing instrument comprising: a barrel having a visible
portion; an ink occlusion body disposed in the barrel; a writing
part including a pen tip; and an ink guiding feed defined by a
hollow tubular body without any capillary material within the
hollow tubular body and lacking capillary force therethrough, and
formed of a transparent or translucent material disposed between
the ink occlusion body and the pen tip in the barrel; wherein ink
impregnated in the ink occlusion body is fed to the pen tip under
capillary force via the ink guiding feed, and a sign of exhausting
the ink fed from the ink occlusion body is detected by visually
observing an empty tubular body of the ink guiding feed through the
visible portion of the barrel.
60. The writing instrument as described in claim 59, wherein the
visible portion of said barrel generally corresponds at least to a
location of said ink guiding feed within said barrel, said barrel
further including a non-visible portion generally corresponding to
a location of at least one of said writing part and said ink
occlusion body.
61. The writing instrument as described in claim 21, wherein the
ink guiding feed is a hollow tube having a front end part, a rear
end part, and an intermediate part therebetween, the rear end part
of the ink guiding feed being disposed within the ink occlusion
body, the front end part of the ink guiding feed being inserted
into a rear end part of the pen tip, and the intermediate part
being visible via the visible part formed in the barrel.
Description
TECHNICAL FIELD
[0001] The present invention relates to a writing instrument in
which an ink for a writing instrument such as a water-based ink and
an oil-based ink impregnated into an ink occlusion body in a barrel
is fed to a pen tip in a writing part, more specifically to a
writing instrument which can readily detect a sign of exhausting an
ink in a writing instrument having the above structure.
BACKGROUND ART
[0002] A free ink type writing instrument having a collector
structure in which a liquid ink is stored directly in a barrel, a
writing instrument having a structure in which an ink is stored in
an ink reservoir of a cartridge type and a ballpoint pen of a type
in which an ink for a ballpoint pen is filled in a transparent
refill have so far been known as a writing instrument in which a
remaining amount of an ink and a sign of exhausting an ink can be
detected.
[0003] On the other hand, in a writing instrument in which a pen
tip in a writing part is fed with an ink for a writing instrument
such as a water-based ink and an oil-based ink impregnated into an
ink occlusion body in a barrel, a so-called writing instrument of a
sliver type, it is the existing situation that writing instruments
equipped a mechanism in which a sign of exhausting an ink can be
detected have not so far been available.
[0004] Accordingly, in the writing instruments having the above
structures, it is not before an ink is used until starving is
caused during writing that the ink is found to be exhausted, and
then the writing instrument is disposed or reused with
supplementing the ink. However, starving is caused as well due to
drying of the pen tip, and therefore if starving is caused due to
drying of the pen tip though the ink impregnated into the ink
occlusion body sufficiently remains, it is not a substantial sign
of exhausting the ink, and a problem on use is involved
therein.
[0005] On the other hand, disclosed in Japanese Patent Application
Laid-Open No. 270585/1994 is a writing instrument in which a sliver
working as an ink occlusion body is mounted in a transparent barrel
to feed a pen tip in a writing part with an ink impregnated in the
above sliver and in which the inside of the writing instrument can
be visually observed from the sliver up to the pen tip.
[0006] However, in a writing instrument having the above structure,
when an amount of an ink occluded in a sliver is decreased, an
remaining amount of the ink can be observed to some extent by the
degree in the color of the ink occluded in the sliver, but a sign
of exhausting the ink can not surely be detected. Accordingly, a
problem on use is involved as well in the above writing
instrument.
[0007] In light of the problems of the conventional techniques and
the existing situation each described above, the present invention
intends to solve them, and an object of the present invention is to
provide a writing instrument in which a pen tip in a writing part
is fed with an ink for a writing instrument such as a water-based
ink or an oil-based ink impregnated into an ink occlusion body in a
barrel, wherein a sign of exhausting the ink can readily and surely
be detected, and another object thereof is to provide a writing
instrument in which a consumption rate of the ink impregnated into
an ink occlusion body is further improved.
DISCLOSURE OF THE INVENTION
[0008] Intensive researches repeated by the present inventors on
the problems of the conventional techniques described above have
resulted in finding that a writing instrument which meets the
objects described above can be obtained by providing a specific
structure of a barrel in a writing instrument in which an ink
impregnated into an ink occlusion body in a barrel is fed to a pen
tip in a writing part and a specific mechanism for feeding an ink
to a pen tip from an ink occlusion body, and thus the present
invention has come to be completed.
[0009] That is, the writing instrument of the present invention
comprises the following items (1) to (20). [0010] 1. A writing
instrument in which an ink impregnated into an ink occlusion body
in a barrel is fed to a pen tip in a writing part, wherein the ink
impregnated into the ink occlusion body described above is fed to
the pen tip via an ink guiding feed having visibility, and a sign
of exhausting the ink fed from the ink occlusion body is detected
by visually observing the ink guiding feed described above via a
visible part formed in the barrel. [0011] 2. A writing instrument
of a twin type in which an ink impregnated into an ink occlusion
body in a barrel is fed to respective pen tips in writing parts
disposed at both sides of the barrel, wherein the ink fed to either
of the pen tips is fed to the pen tip via an ink guiding feed
having visibility, and a sign of exhausting the ink fed from the
ink occlusion body is detected by visually observing the ink
guiding feed described above via a visible part formed in the
barrel. [0012] 3. The writing instrument as described in the above
item (1) or (2), wherein the ink impregnated into the ink occlusion
body is fed to the ink guiding feed having visibility via an
inter-feeder. [0013] 4. The writing instrument as described in the
above item (3), wherein the inter-feeder is brought into contact
with the inside of the ink occlusion body in a length of 5% or more
based on an overall length of the ink occlusion body. [0014] 5. The
writing instrument as described in the above item (3) or (4),
wherein the inter-feeder has a cross-sectional area of 1 to 90%
based on a cross-sectional area of the ink occlusion body. [0015]
6. The writing instrument as described in any of the above items
(3) to (5), wherein the inter-feeder has larger capillary force
than that of the ink occlusion body. [0016] 7. The writing
instrument as described in any of the above items (3) to (6),
wherein the inter-feeder has a cross-section structure comprising
an inner layer and an outer layer, and the outer layer has larger
capillary force than that of the inner layer. [0017] 8. The writing
instrument as described in any of the above items (3) to (7),
wherein the ink fed to the ink guiding feed having visibility via
the inter-feeder is further fed to the pen tip via a pen tip
feeder. [0018] 9. The writing instrument as described in any of the
above items (3) to (8), wherein the inter-feeder comprises any one
of a fiber bundle feed, a porous sintered body of resin particles
and a sliver feed, and a passage cross-sectional area for an ink
flowing through the ink guiding feed can substantially be
controlled by providing the inter-feeder with continuous passages
while maintaining an apparent cross sectional area of the ink
guiding feed. [0019] 10. The writing instrument as described in any
of the above items (1) to (9), wherein a material of a face of the
ink guiding feed which is brought into contact with the ink or a
material of the ink guiding feed itself has a smaller surface
tension than that of the ink. [0020] 11. The writing instrument as
described in any of the above items (1) to (10), wherein the ink
occlusion body has a distribution in capillary force such that it
is increased toward a pen tip side. [0021] 12. The writing
instrument as described in any of the above items (1) to (11),
wherein an inner diameter of the barrel is narrower toward the pen
tip side. [0022] 13. The writing instrument as described in any of
the above items (1) to (12), wherein plural ribs are formed in an
axial direction on an inner wall of the pen tip side of the barrel.
[0023] 14. The writing instrument as described in any of the above
items (1) to (13), wherein a plurality of the ink guiding feeds
having visibility is provided. [0024] 15. The writing instrument as
described in any of the above items (1) to (14), wherein the ink
impregnated into the ink occlusion body is fed to the pen tip
through an ink-feeder in addition to the ink guiding feed having
visibility. [0025] 16. The writing instrument as described in any
of the above items (1) to (15), wherein a passage cross-sectional
area for the ink flowing through the ink guiding feed and flow
resistance of the ink can substantially be controlled by filling
the ink guiding feed having visibility with a fiber bundle feed or
a porous sintered body of resin particles which has a smaller
surface tension than that of the ink and has a color which is
different from that of the ink while maintaining an apparent
cross-sectional area of the ink guiding feed. [0026] 17. The
writing instrument as described in any of the above items (1) to
(16), wherein the visible part in the barrel has a length of 1 mm
or more and not longer than an overall length of the writing
instrument. [0027] 18. The writing instrument as described in any
of the above items (1) to (17), wherein the ink guiding feed has an
ink passage cross-sectional area of 8.times.10.sup.-2 to 80
mm.sup.2. [0028] 19. The writing instrument as described in any of
the above items (1) to (18), wherein the ink has a surface tension
of 18 mN/or more at 25.degree. C. [0029] 20. The writing instrument
as described in any of the above items (1) to (19), wherein the ink
has a viscosity of 500 mPas or less at 25.degree. C.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] FIG. 1 is a longitudinal cross section of a writing
instrument showing the first embodiment of the present invention,
and
[0031] FIG. 2(a) to (h) are cross sections showing the respective
forms of an ink guiding feed 30.
[0032] FIG. 3 is a partial longitudinal cross section of the
writing instrument showing the first embodiment of the present
invention, and
[0033] FIG. 4(a) is a partial longitudinal cross section showing a
variant example of an ink occlusion body 20; (b) is a partial
longitudinal cross section showing a variant example of a barrel 10
and the ink occlusion body 20; and (c) is a partial longitudinal
cross section showing a variant example of the barrel 10.
[0034] FIG. 5(a) is a partial longitudinal cross section of a
writing instrument showing the second embodiment of the present
invention, and (b) is a partial longitudinal cross section showing
an essential part thereof.
[0035] FIG. 6(a) is a partial longitudinal cross section of a
writing instrument showing the third embodiment of the present
invention, and (b) is a partial longitudinal cross section showing
an essential part thereof.
[0036] FIG. 7(a) is a partial longitudinal cross section of a
writing instrument showing the fourth embodiment of the present
invention; (b) is a perspective view showing an ink guiding feed
thereof; and (c) is a perspective view of the ink guiding feed
showing another embodiment.
[0037] FIG. 8 is a partial longitudinal cross section of a writing
instrument showing the fifth embodiment of the present
invention;
[0038] FIG. 9 is a partial longitudinal cross section of a writing
instrument showing the sixth embodiment of the present invention;
and
[0039] FIG. 10 is a partial longitudinal cross section of a writing
instrument of a twin type showing the seventh embodiment of the
present invention.
[0040] FIG. 11(a) is a partial longitudinal cross section of a
writing instrument showing the eighth embodiment of the present
invention, and (b) is a partial longitudinal cross section showing
an essential part thereof, that is, a connecting state between an
ink guiding feed, an inter-feeder and an ink occlusion body.
[0041] FIG. 12(a) is a partial longitudinal cross section showing a
variant example of an ink occlusion body 20 having an inter-feeder
25; (b) is a partial longitudinal cross section showing a variant
example of the barrel 10 and the ink occlusion body 20 having the
inter-feeder 25; and (c) is a partial longitudinal cross section
showing a variant example of the barrel 10.
[0042] FIG. 13(a) is a partial longitudinal cross section of a
writing instrument showing the ninth embodiment of the present
invention, and (b) is a partial longitudinal cross section showing
an essential part thereof.
[0043] FIG. 14(a) is a partial longitudinal cross section of a
writing instrument showing the tenth embodiment of the present
invention, and (b) is a partial longitudinal cross section showing
an essential part thereof.
[0044] FIG. 15(a) is a partial longitudinal cross section of a
writing instrument showing the eleventh embodiment of the present
invention; (b) is a perspective view showing an ink guiding feed
thereof; and (c) is a perspective view of the ink guiding feed
showing another embodiment.
[0045] FIG. 16 is a partial longitudinal cross section of a writing
instrument showing the twelfth embodiment of the present
invention;
[0046] FIG. 17 is a partial longitudinal cross section of a writing
instrument showing the thirteenth embodiment of the present
invention; and
[0047] FIG. 18 is a partial longitudinal cross section of a writing
instrument showing the fourteenth embodiment of the present
invention.
BEST MODE FOR CARRYING OUT THE INVENTION
[0048] The embodiments of the present invention shall be explained
below in details with reference to the drawings.
[0049] The writing instrument of the present invention comprises:
[0050] (1) a writing instrument in which an ink impregnated into an
ink occlusion body in a barrel is fed to a pen tip in a writing
part, wherein the ink impregnated into the ink occlusion body
described above is fed to the pen tip via an ink guiding feed
having visibility, and a sign of exhausting the ink fed from the
ink occlusion body is detected by visually observing the ink
guiding feed described above via a visible part formed in a barrel
(for example, FIG. 1 to FIG. 9), [0051] (2) a writing instrument of
a twin type in which an ink impregnated into an ink occlusion body
in a barrel is fed to respective pen tips in writing parts disposed
at both sides of the barrel, wherein the ink fed to either of the
pen tips is fed to the pen tip via an ink guiding feed having
visibility, and a sign of exhausting the ink fed from the ink
occlusion body is detected by visually observing the ink guiding
feed described above via a visible part formed in the barrel (for
example, FIG. 10) and
[0052] (3) and (4) the writing instruments as described in the
above item (1) or (2), wherein the ink impregnated into the ink
occlusion body is fed to the ink guiding feed having visibility via
an inter-feeder (for example, FIG. 11 to FIG. 18).
[0053] FIG. 1 to FIG. 3 show the first embodiment of the present
invention, and it can suitably be applied to a felt-tip pen, a
marker and a marker for a white board.
[0054] As shown in FIG. 1 and FIG. 3, the writing instrument A of
the first embodiment is equipped with a barrel 10 which is a
writing instrument main body, an ink occlusion body 20, an ink
guiding feed 30, a pen tip 40 and plug 50.
[0055] The barrel 10 is constituted of, for example, a synthetic
resin, and a small diameter part 10a having a taper part at a tip
side and a large diameter part 10b are integrated. Adopted is a
structure in which an fitting part 11 into which a pen tip 20 is
fitted is present in the small diameter part 10a and in which the
ink occlusion body 20 impregnated with an ink for a writing
instrument and the ink guiding feed 30 are mounted in the inside of
the large diameter part 10b.
[0056] As shown in FIG. 1 and FIG. 3, the tip side of the large
diameter part 10b in the barrel 10 has a visible part 12
constituted of a transparent material or a translucent material so
that the inside of the barrel can visually be observed, and the
other parts are non-visible parts constituted of different
materials.
[0057] The whole part of the barrel 10 may be constituted of a
transparent material or a translucent Material having visibility so
that the whole part of the barrel 10 can visually be observed.
Further, the whole part of the barrel 10 may be constituted of a
transparent material or a translucent material having visibility,
and the other parts than the visible part 12 may be non-visible
parts in the form of a colored part and a decorated part.
[0058] An overall length of the above visible part 12 may be such a
length that the ink guiding feed 30 held in the barrel 10 can
visually be observed through the visible part 12, and it is
preferably 1 mm or more and not longer than an overall length of
the writing instrument main body (barrel in the present
embodiment), more preferably 5 mm or more. If an overall length of
the above visible part 12 is less than 1 mm, a sign of exhausting
the ink is less liable to be visually detected, and the detection
function can not be attained.
[0059] The ink occlusion body 20 is impregnated with an ink for a
writing instrument such as a water-based ink and an oil-based ink,
and it comprises, for example, a fiber bundle comprising a single
one or a combination of two or more of a natural fiber, an animal
hair fiber, a polyacetal base resin, an acryl base resin, a
polyester base resin, a polyamide base resin, a polyurethane base
resin, a polyolefin base resin, a polyvinyl base resin, a
polycarbonate base resin, a polyether base resin and a
polyphenylene base resin, a matter obtained by processing a fiber
bundle such as a felt, and a porous body such as a sponge, a
sintered body of resin particles and a sintered matter. The ink
occlusion body 20 is mounted between a rear holder 21 sealing a
front part of the barrel 10 and the plug 50 in the barrel.
[0060] As shown in FIG. 1, the ink guiding feed 30 is a cylindrical
(tubular) ink passage member having visibility and constituted of,
for example, a transparent material or a translucent material made
of a resin, a rubber or glass. To be specific, the transparent or
translucent resin includes polyolefin base resins such as
polypropylene, polyethylene, cyclic polyolefin and
poly(1-methyl-4-pentene), polycarbonate, polystyrene, polyethylene
terephthalate, polyethylene naphthalate, polybutylene terephthalate
and fluorinated plastics such as a fluororesin and polyvinylidene
fluoride. Further, the transparent or translucent rubber includes
fluorinated rubber and silicone rubber. In the present embodiment,
the ink guiding feed is constituted of polypropylene.
[0061] Further, in the transparent material or translucent material
made of a resin, a rubber or glass described above, at least a face
which is brought into contact with an ink may be subjected to
surface treatment so that a surface energy of the face is reduced
smaller than that of the ink. To be specific, it includes fluorine
coating, fluororesin coating or coating treatment with a silicone
resin comprising a skeleton of dimethylsilicone.
[0062] A rear end part 30a of the above ink guiding feed 30 passes
through the rear holder 21 and is inserted into the ink occlusion
body 20, and a front end part 30b passes through a front holder 22
sealing the inside of the small diameter part 10a in the barrel 10
and is inserted into a rear end part of the pen tip 40. This allows
a visible space part 13 to be formed in the barrel 10, and the ink
guiding feed 30 is held in a central part of the above visible
space part 13 by the rear holder 21 sealing the inside of the
barrel 10 and the front holder 22. An air flow groove in which air
can flow is formed on an inner wall face in the small diameter part
10a and the front part of the large diameter part 10b in the barrel
10 from an atmospheric side of the pen tip 40 to the front part of
the barrel 10 in which the ink occlusion body 20 is mounted, and
air can flow from an atmospheric side of the pen tip 40 to the
inside of the barrel 10 as is the case with a conventional writing
instrument of a sliver type.
[0063] The above structure makes it easy to visually observe the
ink guiding feed 30 via the visible part 12 in the barrel 10. The
ink impregnated into the ink occlusion body 20 flows in the ink
guiding feed 30 by virtue of capillary force and is fed to the pen
tip 40 via the above ink guiding feed 30.
[0064] An overall length of the above ink guiding feed 30 is
suitably determined depending on the kind of the pen tip 40, and
since usually a length from a front end of the ink occlusion body
20 up to the pen tip 40 is determined by capillary force thereof,
the overall length of the ink guiding feed is determined to be a
length reaching the above length. An ink passage cross-sectional
area of the ink guiding feed 30 is preferably 8.times.10.sup.-2 to
80 mm.sup.2, more preferably 0.5 to 20 mm.sup.2 in order to allow
the ink to more smoothly flow in it.
[0065] If the above ink passage cross-sectional area is less than
8.times.10.sup.-2 mm.sup.2, the ink flow amount is decreased, and
the ink followability in writing is inferior. On the other hand, if
it exceeds 80 mm.sup.2, the ink guiding feed 30 can not be long,
and it is difficult to visually detect a sign of exhausting the
ink. If the ink guiding feed 30 is long in the case of a
cross-sectional area exceeding 80 mm.sup.2, it is easy to visually
detect a sign of exhausting the ink. In this case, however, an
excess amount of the ink discharges from the pen tip in writing
with the pen tip turning downward.
[0066] Further, in order to feed smoothly the ink from the ink
occlusion body 20 up to the pen tip 40, a surface tension of a face
of the ink guiding feed 30 brought into contact with the ink or the
material itself of the ink guiding feed 30 is preferably smaller
than that of the ink. When a surface tension of the face of the ink
guiding feed 30 brought into contact with the ink is larger than
that of the ink, a surface tension of the face of the ink guiding
feed 30 brought into contact with the ink can be smaller than a
surface tension of the ink by subjecting the face of the ink
guiding feed to fluorine treatment or silicon treatment.
[0067] Further, as shown in FIG. 2(a) to (h), cross-sectional
patterns of the ink guiding feed 30 include, for example, a circle
form [FIG. 2(a)], polygonal forms such as a triangular form [FIG.
2(b)], a quadrangular form [FIG. 2(c)], a pentagonal form [FIG.
2(d)], a hexagonal form [FIG. 2(e)] and a rhombic form [FIG. 2(g)],
an elliptic form [FIG. 2(f)] and a star form [FIG. (h)]. It shall
not specifically be restricted as long as the ink is smoothly fed
from the ink occlusion body 20 up to the pen tip 40 and the
visibility is not obstructed. The ink guiding feed 30 of the
present embodiment has a circular cross-sectional form.
[0068] The pen tip 40 comprises, for example, a parallel fiber
bundle comprising a single one or a combination of two or more of a
natural fiber, an animal hair fiber, a polyacetal base resin, an
acryl base resin, a polyester base resin, a polyamide base resin, a
polyurethane base resin, a polyolefin base resin, a polyvinyl base
resin, a polycarbonate base resin, a polyether base resin and a
polyphenylene base resin, a fiber feed obtained by processing a
fiber bundle such as a felt or obtained by processing the above
fiber bundles with a resin or a pen tip comprising a porous body
obtained by fusing various plastic powders. Various forms are
selected as a form thereof depending on a form of the writing
instrument, for example, a marking pen, a felt-tip pen and the
like.
[0069] The ink impregnated into the ink occlusion body 20 described
above shall not specifically be restricted as long as it is an ink
for a writing instrument such as a water-based ink and an oil-based
ink having the respective blend compositions which are usually
used, and it includes water-based ink and oil-based inks for a
felt-tip pen, a marking pen, a ballpoint pen and a white board
depending on uses. A surface tension of the ink is controlled
preferably to 18 mN/m or more, more preferably to 20 to 50 mN/m at
25.degree. C. in order to detect well a sign of exhausting the ink
in the ink guiding feed 30. A surface tension of the ink can be
controlled by blending, if necessary, the ink with a
surfactant.
[0070] Further, a viscosity of the ink is controlled preferably to
500 mPas or less, more preferably 200 mPas or less and particularly
preferably 1 to 100 mPas at 25.degree. C. in order to smoothly feed
the ink to the ink occlusion body 20, the ink guiding feed 30 and
the pen tip 40. If the above viscosity of the ink exceeds 500 mPas,
the ink is deteriorated in fluidity and does not discharge in a
sufficiently large amount, so that starving of the drawn lines and
incapability of quick writing due to a shortage in the discharge
amount are brought about in a certain case. A viscosity of the ink
can be controlled by blending, if necessary, the ink with a
thickener.
[0071] In the writing instrument A of the present first embodiment
which is constituted in the manner described above, the ink
impregnated in the ink occlusion body 20 passes through the ink
guiding feed 30 and penetrates into the pen tip 40 by virtue of a
capillary phenomenon, as shown in FIG. 1 and FIG. 3, whereby
writing becomes possible.
[0072] The above writing instrument A of the first embodiment has a
structure in which the ink impregnated into the ink occlusion body
20 always passes through the ink guiding feed 30 and is fed to the
pen tip 40, and therefore when the ink impregnated into the ink
occlusion body 20 is decreased and exhausted by writing, that can
be found by the absence of the ink passing through the ink guiding
feed 30.
[0073] That is, in the writing instrument A of the present
embodiment, a sign of exhausting the ink fed from the ink occlusion
body 20 can be detected by visually observing the ink guiding feed
30 via the visible part 12 formed in the barrel 10. Accordingly, it
can clearly and easily be judged from visual observation whether or
not starving at the pen tip 40 is caused by drying at the pen tip
40 or substantial exhaustion of the ink due to consumption.
[0074] In the present embodiment, the plug 50 is fixed at the rear
end part in the barrel 10, however a mechanism in which the plug 50
can detachably be mounted at the rear end part of the barrel 10 is
adopted and, the plug is detached to replenish the ink after
detecting exhaustion of the ink by visually observing the ink
guiding feed 30, whereby the writing instrument can be reused.
Further, in order to prevent the ink from being fed excessively
from the ink guiding feed 30 to the pen tip 40 and leaking from the
pen tip 40 when the above writing instrument A is used under the
environment of a high temperature, an ink absorber may be provided
in the periphery of the rear end part of the pen tip 40. The above
ink absorber is disposed at a space 14 formed in the periphery of
the rear end part of the pen tip 40 in the small diameter part
10a.
[0075] Further, in the present embodiment, the end faces of the ink
occlusion body 20 are closed against the outside air by the plug 50
and the front holder 22 which closes the end face of the ink
occlusion body 20 at the side where the ink guiding feed 30 and the
ink occlusion body 20 are joined, and therefore the outside air
does not flow in, so that the air can be prevented from flowing
into the ink guiding feed 30.
[0076] FIG. 4(a) to (h) are variant examples of the first
embodiment described above. FIG. 4(a) is a form in which capillary
force of the ink occlusion body is increased toward a pen tip side,
for example, a structure in which a space between the fiber bundles
constituting the ink occlusion body 20 is narrower toward the pen
tip side, that is, the ink occlusion body is constituted of a
coarse part 20a and a fine part 20b.
[0077] FIG. 4(b) is of a structure in which an inner diameter of
the barrel 10 is narrower toward the pen tip side (tapering form),
and the ink occlusion body 20 is as well of a structure in which it
is narrower toward the pen tip side. FIG. 4(c) is of a structure in
which plural ribs 15, 15--are formed in an axial direction on an
inner wall part in the barrel 10 mounting the ink occlusion body
20.
[0078] The ink impregnated into the ink occlusion body 20 flows
well into the ink guiding feed 30 and is fed well to the pen tip 40
by employing the respective structures of FIG. 4(a) to (c) or a
combination thereof in the writing instrument A of the first
embodiment described above.
[0079] FIGS. 5(a) and (b) show the second embodiment of the present
invention. The writing instrument B of the present second
embodiment is different from the writing instrument A of the first
embodiment described above only in the point that provided are
plural ink guiding feeds 31, 32 having visibility, to the specific,
two ink guiding feeds 31, 32 which are constituted of a transparent
member or a translucent member and which have different lengths. In
FIGS. 5(a) and (b), the explanation of the same structure as in the
first embodiment described above shall be omitted by affixing the
same reference numerals.
[0080] In the present second embodiment, rear end parts 31a, 32a of
both the ink guiding feed 31 having a long overall length and the
ink guiding feed 32 having a short overall length are inserted, as
shown in FIG. 5(b), into the inside of an ink occlusion body 20
with a difference X in length passing through a rear holder 21, and
front end parts 31b, 32b are inserted into a rear end part of a pen
tip 40 with the end parts thereof being arranged respectively to
the same level passing through a front holder 22 sealing a small
diameter part 10a in a barrel 10. This allows the ink guiding feeds
31, 32 to be held in the central part of the above visible space
part 13.
[0081] In the above writing instrument B of the present second
embodiment, the ink impregnated in the ink occlusion body 20 passes
through the ink guiding feeds 31, 32 and is fed to the pen tip 40
as is the case with the first embodiment described above, whereby
writing becomes possible. Further, in the above writing instrument
B, the respective end parts 31a, 32a are inserted into the ink
occlusion body 20 with a difference X in length. Thus, the ink
impregnated into the ink occlusion body 20 at the maximum rate is
gradually consumed by writing, and when the ink stops flowing
through the long ink guiding feed 31, it is detected via the
visible part 12 that, for example, about 90% of the ink remains in
the ink occlusion body 20. Then, the ink is consumed more by
further writing, and when the ink stops flowing through the short
ink guiding feed 32, it can be detected via the visible part 12
that the ink is exhausted from the ink occlusion body 20.
[0082] Accordingly, in the writing instrument B of the present
second embodiment, the respective end parts 31a, 32a of the ink
guiding feeds inserted into the ink occlusion body 20 are disposed
with a difference in length, whereby an amount of the ink remaining
in the ink occlusion body 20 and a sign of exhausting the ink can
be detected by visually observing the ink guiding feeds 31, 32
described above via the visible part 12 formed in the barrel
10.
[0083] In the second embodiment described above, the ink guiding
feeds 31, 32 each having a different length are used, but the ink
guiding feeds having the same length may be used. In this case, the
ink can further smoothly be fed to the pen tip 40.
[0084] In the second embodiment described above, the number of the
ink guiding feeds is set to two feeds, but three or more ink
guiding feeds each having a different length or the same length may
suitably be disposed depending on the uses of the writing
instrument.
[0085] Further, the variant examples shown in FIG. 4(a) to (c) may
be applied to the writing instrument B of the second embodiment
described above (the same shall apply to the following
embodiments).
[0086] FIGS. 6(a) and (b) show the third embodiment of the present
invention. The writing instrument C of the present third embodiment
is different from the writing instrument A of the first embodiment
described above only in the point that an ink impregnated into an
ink occlusion body 20 is fed to a pen tip 40 via an ink feeder 34
in addition to an ink guiding feed 33 having visibility. In FIGS.
6(a) and (b), the explanation of the same structure as in the first
embodiment described above shall be omitted by affixing the same
reference numerals.
[0087] In the present third embodiment, both the ink guiding feed
33 and the ink feeder 34 are inserted, as shown in FIG. 6(b), into
the ink occlusion body 20 passing through a rear holder 21, and
both front end parts thereof are inserted respectively into a rear
end part of the pen tip 40 with the end parts thereof being
arranged to the same level passing through a front holder sealing a
small diameter part 10a in a barrel 10. This allows the ink guiding
feed 33 and the ink feeder 34 to be held in the central part of the
above visible space part.
[0088] In the writing instrument C of the above present second
embodiment, the ink impregnated into the ink occlusion body 20
passes through the ink guiding feed 33 having visibility which is
constituted in the same manner as in the first embodiment described
above and the ink feeder 34 comprising a fiber bundle and the like
and is fed to the pen tip 40, whereby writing becomes possible. In
the above writing instrument C, the ink can be fed to the pen tip
40 via the ink feeder 34 in addition to the ink guiding feed 33,
and therefore the ink can further smoothly be fed to the pen tip
40. In order to surely detect a sign of exhausting the ink by
visually observing the ink guiding feed 33 via a visible part 12,
ink-feeding force of the ink feeder 34 to the pen tip is set
preferably weaker than ink-feeding force of the ink guiding feed
33.
[0089] FIG. 7 (a) to (c) show the fourth embodiment of the present
invention. The writing instrument D of the present fourth
embodiment is different from the writing instrument A of the first
embodiment described above only in the point that an ink guiding
feed 35 is filled with a fiber bundle or a porous sintered body of
resin particles which has a smaller surface tension than that of an
ink impregnated into an ink occlusion body 20 and has a different
color from that of the ink, for example, a fiber bundle or a porous
sintered body of resin particles 36 comprising polyethylene
tetrafluoride [FIG. 7(b)] or a fiber bundle or a porous sintered
body of resin particles 37 comprising polyvinylidene fluoride [FIG.
7(c)], whereby a passage cross-sectional area for the ink flowing
through the ink guiding feed 35 and flow resistance of the ink can
substantially be controlled while maintaining an apparent
cross-sectional area of the ink guiding feed 35. In FIGS. 7(a) and
(b), the explanation of the same structure as in the first
embodiment described above shall be omitted by affixing the same
reference numerals. Preferably used is the foregoing fiber bundle
or porous sintered body of resin particles in which a material
itself has a lower surface energy than that of the ink or in which
a surface energy is reduced to a lower level than that of the ink
by subjecting to surface treatment.
[0090] The fiber bundle or porous sintered body of resin particles
36 or 37 of the present fourth embodiment has preferably a
different color from that of the ink impregnated into the ink
occlusion body 20, more preferably a color which is masked by the
color of the ink used. For example, it is white when the ink is
black, blue when the ink is red and black when the ink is yellow,
and it may be transparent or translucent but does not necessarily
have to be colored.
[0091] In the writing instrument D of the present fourth
embodiment, the ink impregnated into the ink occlusion body 20
passes through the ink guiding feed 35 having visibility into which
the bar-like fiber bundle or porous sintered body of resin
particles 36 or 37 is inserted without bringing into contact with
an inner wall of the ink guiding feed 35, and it is fed to the pen
tip 40, whereby writing becomes possible. In the above writing
instrument D, the fiber bundle or porous sintered body of resin
particles 36 or 37 which has a smaller surface tension than that of
the ink and has a different color from that of the ink is inserted
into the inside of the ink guiding feed 35 without bringing into
contact with an inner wall of the ink guiding feed 35, that is, a
space in which the ink can flow is secured, whereby a passage
cross-sectional area for the ink flowing through the ink guiding
feed 35 can be reduced to thereby substantially reduce the
cross-sectional area while maintaining an apparent cross-sectional
area of the ink guiding feed. Thus, a volume of the ink flowing
through the ink guiding feed 35 can be reduced as well, and
therefore a function of detecting a sign of exhausting the ink and
a problem of ink excess discharge at that time can be solved at the
same time.
[0092] Further, in the writing instrument D of the present fourth
embodiment, when the ink is exhausted (run out), the color of the
fiber bundle or porous sintered body of resin particles 36 or 37
having a different color from that of the ink can be visually
observed from the ink feed 35, and therefore a sign of exhausting
the ink can more surely be visually observed, which is different
from that a sign of exhausting the ink in the writing instruments
of the first to third embodiments is detected by visually observing
exhaustion of the ink in the ink guiding feed.
[0093] FIG. 8 shows the fifth embodiment of the present invention.
The writing instrument E of the present fifth embodiment is
different from the writing instrument A of the first embodiment
described above in the point that a pen tip 40 is for underline,
the point that a front barrel 41 for holding the pen tip comprises
a different member and is fixed at a front end of a barrel 10, the
point that a rear holder 21 and a front holder 22 are omitted and
the point that a holding stage 23 for holding an ink occlusion body
20 is provided peripherally in place of the rear holder 21. Feeding
of the ink and a sign of exhausting the ink are detected by
visually observing an ink guiding feed via a visible part 12 as is
the case with the writing instrument A.
[0094] FIG. 9 shows the sixth embodiment of the present invention.
The writing instrument F of the present sixth embodiment is
different from the writing instrument A of the first embodiment
described above in the point that a pen tip 40 is for a ballpoint
pen equipped with an ink guiding feed, the point that a front
barrel 42 for holding the pen tip comprises a different member and
is fixed at a front end of a barrel 10 and the point that a front
holder 22 is omitted. Feeding of the ink and a sign of exhausting
the ink are detected by visually observing an ink guiding feed 30
via a visible part 12 as is the case with the writing instrument
A.
[0095] FIG. 10 shows the seventh embodiment of the present
invention, and it is a writing instrument G of a twin type in which
an ink impregnated into an ink occlusion body 20 in a barrel 10 is
fed to a pen tip 40 for underline and a pen tip 45 for a felt-tip
pen which are writing parts provided at both sides of the barrel
10.
[0096] The ink is fed from the ink occlusion body 20 via an ink
guiding feed 30 having visibility at a pen tip 40 side as is the
case with the fifth embodiment shown in FIG. 8, and at a pen tip 45
side, a rear end part of the pen tip 45 is inserted into the ink
occlusion body 20 and brought into contact therewith, whereby the
ink is fed directly from the ink occlusion body 20. The reference
numeral 46 shows a front barrel part molded integrally with the
barrel 10. Further, air can flow into the barrel 10 from an
atmospheric side of the pen tip 45 as well through an air flow
groove formed on an inner wall of the front barrel part 46 as is
the case with a conventional writing instrument of a sliver
type.
[0097] In the above writing instrument G of a twin type, the ink is
consumed at the respective pen tips 40, 45, and as is the case with
the fifth embodiment, a sign of exhausting the ink in the ink
occlusion body 20 is detected by visually observing an ink guiding
feed 30 via a visible part 12.
[0098] The visible part 12, the ink guiding feed 30 and the like
are provided at a pen tip 40 side in the embodiment described
above. On the contrary, it is allowed that the visible part 12, the
ink guiding feed 30 and the like are provided at a pen tip 45 side
and that a rear end part of the pen tip 40 is inserted into and
brought into contact with the ink occlusion body 20, whereby the
ink is fed directly from the ink occlusion body 20.
[0099] FIG. 11 to FIG. 18 show respective embodiments having a
structure in which an ink impregnated into an ink occlusion body 20
is fed to an ink guiding feed 30 having visibility via an
inter-feeder 25 in the writing instruments A to G of the respective
embodiments shown in FIG. 1 to FIG. 10. In the writing instruments
of the respective embodiments shown in FIG. 11 to FIG. 18, the
explanation of the same structures as in the writing instruments A
to G of the first to seventh embodiments described above shall be
omitted by affixing the same reference numerals.
[0100] FIG. 11 shows the eighth embodiment of the present
invention. The writing instrument H of the above eighth embodiment
has a structure in which an ink impregnated into an ink occlusion
body 20 is fed to an ink guiding feed 30 having visibility via an
inter-feeder 25 in the writing instrument A of the first embodiment
shown in FIGS. 1 to 3.
[0101] The inter-feeder 25 comprises, as is the case with the ink
occlusion body 20, a fiber bundle, a fiber bundle feed obtained by
processing a fiber bundle such as felt, a hard sponge, a porous
sintered body of resin particles comprising resin particle-sintered
matter or a sliver feed each having continuous pores (passages),
and a form and a structure thereof shall not specifically be
restricted as long as the ink impregnated into the ink occlusion
body 20 can be fed to the ink guiding feed 30 having visibility via
the inter-feeder 25. It includes, for example, a structure in which
as shown in FIGS. 11(a) and (b), the inter-feeder 25 has at a front
end part, an inserting part 26 which is inserted into a rear end
part 30a of the ink guiding feed 30 and has an acute angle part 27
having an acute angular form at a rear end part thereof. Further, a
cavity part 20a which can bring into contact with an outer face of
the inter-feeder 25 described above is provided at a front end side
of the ink occlusion body 20. The ink impregnated into the ink
occlusion body 20 can more efficiently be fed to the ink guiding
feed 30 having visibility via the inter-feeder 25 owing to the
structure of the inter-feeder 25 having the inserting part 26 and
the acute angle part 27 and the ink occlusion body 20 having the
cavity part 20a each shown in FIGS. 11(a) and (b).
[0102] Further, the ink impregnated into the ink occlusion body 20
can efficiently be fed to the ink guiding feed 30 by making
capillary force of the inter-feeder 25 larger than capillary force
of the ink occlusion body 20, providing the inter-feeder 25 with a
cross-sectional structure having an inner layer part and an outer
layer part and making capillary force of the outer layer part
larger than capillary force of the inner layer part, for example,
making a density of the fiber bundle in the outer layer fine and
making a density of the fiber bundle in the inner layer coarse.
[0103] In the above case, the inter-feeder 25 is brought into
contact with the ink occlusion body 20 in a length of 5% or more,
preferably 10% or more and 100% or less based on an overall length
(L) of the ink occlusion body 20, that is, a length L.sub.1 of the
inter-feeder 25 brought into contact with the ink occlusion body 20
is 5% or more, preferably 10% or more based on an overall length L
of the ink occlusion body 20, and the inter-feeder 25 is brought
into contact with the ink occlusion body 20 in a length of more
preferably 20% or more and 100% or less, particularly preferably
50% or more and 100% or less. This makes it possible to more
efficiently feed the ink contained in the ink occlusion body 20 to
the ink guiding feed 30. A length L.sub.1 of the inter-feeder 25
shown in FIGS. 11(a) and (b) is set to 20% based on an overall
length L of the ink occlusion body 20. If the length brought into
contact with the ink occlusion body 20 is less than 5%, the ink
consumption rate is reduced to the same level of a conventional
writing instrument of a sliver type in a certain case.
[0104] Further, a cross-sectional area W.sub.1 of the inter-feeder
25 is 1 to 90%, preferably 5 to 50% and more preferably 10 to 25%
based on a cross-sectional area W of the ink occlusion body 20.
[0105] If a cross-sectional area W.sub.1 of the above an
inter-feeder 25 is less than 1%, an amount of the ink fed from the
ink occlusion body 20 is short, though depending on the form of the
pen tip 40, and brought about are the problems that the drawn lines
cause starving and that the followability to quick writing is
inferior. On the other hand, if it exceeds 90%, not only the
inter-feeder 25 is less liable to be inserted into the ink
occlusion body 20, but also the function of the ink occlusion body
20 decreases, and the writing instrument can not be distinguished
from a conventional writing instrument of a sliver type having the
inter-feeder 25 in place of the occlusion body 20.
[0106] A cross-sectional area W.sub.1 of the inter-feeder 25 is set
to 1 to 90% based on a cross-sectional area W of the ink occlusion
body 20, whereby the ink impregnated into the ink occlusion body 20
can efficiently be fed to the ink guiding feed 30. A
cross-sectional area W.sub.1 of the inter-feeder 25 shown in FIGS.
11(a) and (b) is set to 60% based on a cross-sectional area W of
the ink occlusion body 20.
[0107] In the writing instrument H of the present eighth embodiment
constituted in the manner described above, the ink impregnated into
the ink occlusion body 20 passes through, as shown in FIG. 11, the
ink guiding feed 30 via the inter-feeder 25 and penetrates into the
pen tip 40 to make writing possible. In the present embodiment, the
ink impregnated into the ink occlusion body 20 is not introduced
directly into the ink guiding feed by virtue of capillary force,
and it is introduced into the ink guiding feed 30 via the
inter-feeder 25, so that the ink impregnated into the ink occlusion
body 20 is introduced efficiently and smoothly into the ink guiding
feed 30.
[0108] In the above writing instrument H of the eleventh
embodiment, employed is a structure in which the ink impregnated
into the ink occlusion body 20 usually passes through the ink
guiding feed 30 via the inter-feeder 25 and is fed to the pen tip
40, and therefore when the ink impregnated into the ink occlusion
body 20 is decreased and exhausted by writing, that can be found by
the absence of the ink passing through the ink guiding feed 30.
[0109] That is, in the writing instrument H of the present
embodiment, a sign of exhausting the ink fed from the ink occlusion
body 20 can be detected by visually observing the ink guiding feed
30 described above via the visible part 12 formed in the barrel 10.
Accordingly, it can clearly and easily be judged from visual
observation whether or not starving at the pen tip 40 is caused by
drying at the pen tip 40 or substantial exhaustion of the ink due
to consumption.
[0110] In the writing instrument H of the present eighth embodiment
described above, the inter-feeder 25 comprises any one of a fiber
bundle feed, a porous sintered body of resin particles and a sliver
feed, and the above an inter-feeder 25 is provided with continuous
passages, whereby a passage cross-sectional area for the ink
flowing through the ink guiding feed 30 can substantially be
controlled while maintaining an apparent cross-sectional area of
the ink guiding feed. That is, controlling of the ink passage
cross-sectional area makes the ink contained in the ink guiding
feed 30 less liable to move due to passage resistance when impact
is exerted by falling of the writing instrument to make it possible
to inhibit the ink from dropping from a pen tip 40. Further,
controlling of the ink passage cross-sectional area makes it
possible to suppress the ink discharge amount after detecting
exhaustion of the ink to inhibit inferior writing caused by excess
flowing of the ink.
[0111] FIG. 12(a) to (c) are variant examples of the eighth
embodiment described above. FIG. 12(a) has a form in which
capillary force of the ink occlusion body is increased more toward
a pen tip side, for example, a structure in which a space between
the fiber bundles constituting the ink occlusion body 20 is
narrower toward the pen tip side, that is, the occlusion body is
constituted from a coarse part 20a and a fine part 20b.
[0112] FIG. 12(b) is of a structure in which an inner diameter of
the barrel 10 is narrower toward the pen tip side (tapering form),
and the ink occlusion body 20 is as well of a structure in which it
is narrower toward the pen tip side. A width (diameter) of the
inter-feeder 25 is approximately the same as an inner diameter of
the ink guiding feed 30.
[0113] FIG. 12(c) is of a structure in which plural ribs 15,
15--are formed in an axial direction on the inner wall of the
barrel 10 mounting the ink occlusion body 20.
[0114] The ink impregnated into the ink occlusion body 20 flows
well into the ink guiding feed 30 via the inter-feeder 25 and is
fed well to the pen tip 40 by employing the above respective
structures of FIG. 12(a) to (c) or a combination thereof to the
writing instrument H of the eighth embodiment described above.
[0115] FIGS.. 13(a) and (b) show the ninth embodiment of the
present invention. The writing instrument I of the present ninth
embodiment is different from the writing instrument H of the ninth
embodiment described above only in the point that it is of a
structure in which an ink fed to an ink guiding feed 30 having
visibility from an inter-feeder 25 is fed to a pen tip 40 via a pen
tip feeder 28 inserted into a front end part 30b of the ink guiding
feed 30.
[0116] In the writing instrument I of the present ninth embodiment,
the ink impregnated into the ink occlusion body 20 passes through
the ink guiding feed 30 via the inter-feeder 25 and is smoothly fed
to the pen tip 40 via the pen tip feeder 28 as is the case with the
eighth embodiment described above, whereby writing becomes
possible. In the above writing instrument I, a sign of exhausting
the ink contained in the ink occlusion body 20 can be detected by
visually observing the ink guiding feed 30 described above via a
visible part 12 formed in a barrel 10.
[0117] In the embodiment described above, the pen tip feeder 28 is
separately provided, and it may be of a structure in which the pen
tip 40 is integrated with the pen tip feeder 28, that is, an
integrated structure in which a rear end part of the pen tip 40 is
the pen tip feeder 28.
[0118] Further, variant examples shown in FIG. 12(a) to (c) may be
applied to the writing instrument I of the ninth embodiment
described above (the same shall apply to the following
embodiments).
[0119] FIGS. 14(a) and (b) show the tenth embodiment of the present
invention, and the writing instrument J of the above tenth
embodiment has a structure in which the writing instrument B of the
second embodiment shown in FIG. 5 is provided with inter-feeders
25b, 25c.
[0120] The writing instrument J of the present tenth embodiment is
different from the writing instrument H of the eighth embodiment
described above only in the point that provided are plural ink
guiding feeds 31, 32 having visibility, to be specific two ink
guiding feeds 31, 32 which are constituted of transparent members
or translucent members having different lengths, the point that an
ink impregnated into an ink occlusion body 20 is fed to the ink
guiding feeds 31, 32 having visibility via respective inter-feeders
25b, 25c having different lengths and the point that the widths
(diameters) of the inter-feeders 25b, 25c are controlled to
approximately the same as the respective inner diameters of the ink
guiding feeds 31, 32.
[0121] In the writing instrument J of the present tenth embodiment,
rear end parts 31a, 32a of both the ink guiding feed 31 having a
long overall length and the ink guiding feed 32 having a short
overall length are inserted, as shown in FIG. 14(b), into the
inside of the ink occlusion body 20 with a difference X.sub.1 in
length passing through a rear holder 21, and front end parts 31b,
32b are inserted into a rear end part of the pen tip 40 with the
end parts thereof being arranged to the same level passing through
a front holder 22 sealing a small diameter part 10a in a barrel 10.
This allows the ink guiding feeds 31, 32 to be held in the central
part of the above visible space part 13.
[0122] In the writing instrument J of the above present tenth
embodiment, the ink impregnated into the ink occlusion body 20
passes through the ink guiding feeds 31, 32 via the inter-feeders
25b, 25c and is fed to the pen tip 40 as is the case with the
eighth embodiment described above, whereby writing becomes
possible. Further, in the above writing instrument B, the
respective end parts 31a, 32a of the ink guiding feeds are inserted
into the ink occlusion body 20 with a difference X.sub.1 in length,
and the respective end parts of the inter-feeders 25b, 25c are
inserted into the ink occlusion body 20 with a difference X.sub.2
in length. Accordingly, the ink impregnated into the ink occlusion
body at the maximum rate is gradually consumed by writing, and when
the ink stops flowing through the long ink guiding feed 31 via the
inter-feeder 25b, it is detected via the visible part 12 that, for
example, about 80% of the ink remains in the ink occlusion body 20.
Then, the ink is consumed by further writing, and when the ink
stops flowing through the short ink guiding feed 32 via the
inter-feeder 25c, it can be detected via the visible part 12 that
the ink is exhausted from the ink occlusion body 20.
[0123] Accordingly, in the writing instrument J of the present
tenth embodiment, the respective end parts 31a, 32a of the ink
guiding feeds are disposed with a difference of X.sub.1 in length,
and the respective end parts of the inter-feeders 25b, 25c are
disposed with a difference of X.sub.2 in length, whereby an amount
of the ink remaining in the ink occlusion body 20 and a sign of
exhausting the ink can be detected by visually observing the ink
guiding feeds 31, 32 described above via the visible part 12 formed
in the barrel 10.
[0124] In the tenth embodiment described above, the ink guiding
feeds 31, 32 each having a different length are used, but if the
ink guiding feeds having the same length and the inter-feeders 25b,
25c each having a different length are used, a remaining amount of
the ink and a sign of exhaustion can be detected in the same manner
described above.
[0125] In the tenth embodiment described above, the number of the
ink guiding feeds has been set to two feeds, but three or more ink
guiding feeds each having different lengths or the same length may
suitably be disposed depending on the uses of the writing
instrument.
[0126] FIG. 15(a) to (c) show the eleventh embodiment of the
present invention, and the writing instrument K of the above
eleventh embodiment is of a structure in which the writing
instrument D of the fourth embodiment shown in FIG. 7 is provided
with an inter-feeder 25d.
[0127] The writing instrument K of the present eleventh embodiment
is different from the writing instrument H of the eighth embodiment
described above only in the point that an ink guiding feed 35 is
filled with a fiber bundle or a porous sintered body of resin
particles which has a smaller surface tension than that of an ink
impregnated into an ink occlusion body 20 and has a different color
from that of the ink, for example, a fiber bundle or a porous
sintered body of resin particles 36 comprising polyethylene
tetrafluoride [FIG. 15(b)] or a fiber bundle or a porous sintered
body of resin particles 37 comprising polyvinylidene fluoride [FIG.
15(c)], whereby a passage cross-sectional area for the ink flowing
through the ink guiding feed and flow resistance of the ink are
substantially controlled while maintaining an apparent
cross-sectional area of the ink guiding feed 35. Since an inserted
part of an inter-feeder 25 is inserted into a rear end part of the
ink guiding feed 35, a length of the fiber bundle or the porous
sintered body of resin particles 36 or 37 is shorter than a length
of the ink guiding feed 30.
[0128] Preferably used is the foregoing fiber bundle or porous
sintered body of resin particles the material itself of which has a
lower surface energy than that of the ink or in which a surface
energy is reduced to a lower level than that of the ink by
subjecting to surface treatment.
[0129] The fiber bundle or porous sintered body of resin particles
36 or 37 of the present eleventh embodiment has preferably a
different color from that of the ink impregnated into the ink
occlusion body 20, more preferably a color which is masked by the
color of the ink used. For example, it is white when the ink is
black, blue when the ink is red and black when the ink is yellow,
and it may be transparent or translucent but does not necessarily
have to be colored.
[0130] In the writing instrument K of the present eleventh
embodiment, the ink impregnated into the ink occlusion body 20
passes, via the inter-feeder 25d, through the ink guiding feed 35
having visibility into which the bar-like fiber bundle or porous
sintered body of resin particles 36 or 37 is inserted without
bringing into contact with an inner wall of the ink guiding feed
35, and it is fed to the pen tip 40, whereby writing becomes
possible. In the above writing instrument D, the fiber bundle or
porous sintered body of resin particles 36 or 37 which has a
smaller surface tension than that of the ink and has a different
color from that of the ink is provided in the inside of the ink
guiding feed 35 without bringing into contact with an inner wall of
the ink guiding feed 35, whereby a passage cross-sectional area for
the ink flowing through the ink guiding feed 35 can be reduced to
thereby substantially reduce the cross-sectional area of the ink
guiding feed while maintaining an apparent cross-sectional area.
Thus, a volume of the ink flowing through the ink guiding feed 35
can be reduced as well, and therefore a function of detecting a
sign of exhausting the ink and a problem of ink excess discharge at
that time can be solved at the same time.
[0131] Further, in the writing instrument K of the present eleventh
embodiment, when the ink is exhausted (run out), the color of the
fiber bundle or porous sintered body of resin particles 36 or 37
which has a different color from that of the ink can be visually
observed from the ink guiding feed 35, and therefore a sign of
exhausting the ink can more clearly be observed, which is different
from that a sign of exhausting the ink in the writing instruments
of the eighth to tenth embodiments is detected by visually
observing the exhaustion of the ink in the ink guiding feed.
[0132] FIG. 16 shows the twelfth embodiment of the present
invention, and the writing instrument M of the above twelfth
embodiment is of a structure in which the writing instrument E of
the fifth embodiment shown in FIG. 8 is provided with an
inter-feeder 25e.
[0133] The writing instrument M of the present twelfth embodiment
is different from the writing instrument H of the eighth embodiment
described above in the point that a pen tip 40 is for a
highlighter, the point that a front barrel 41 for holding the pen
tip comprises a different member and is fixed at a front end of a
barrel 10, the point that the rear holder 21 and the front holder
22 are omitted, the point that a holding stage part 23 is provided
peripherally in place of the front holder 22 and the point that the
inter-feeder 25e has a different form and size. Feeding of the ink
and a sign of exhausting the ink are detected by visually observing
an ink guiding feed 30 via a visible part 12 as is the case with
the writing instruments A and H.
[0134] FIG. 17 shows the thirteenth embodiment of the present
invention, and the writing instrument N of the above thirteenth
embodiment is of a structure in which the writing instrument F of
the sixth embodiment shown in FIG. 9 is provided with an
inter-feeder 25f.
[0135] The writing instrument N of the present thirteenth
embodiment is different from the writing instrument H of the eighth
embodiment described above in the point that a pen tip is for a
ballpoint pen equipped with an ink guiding feed, the point that a
front barrel 42 for holding the pen tip comprises a different
member and is fixed at a front end of a barrel 10, the point that
the front holder 22 is omitted and the point that the inter-feeder
25f has a different form and size. Feeding of the ink and a sign of
exhausting the ink are detected by visually observing an ink
guiding feed 30 via a visible part 12 as is the case with the
writing instruments A and H.
[0136] FIG. 18 show the fourteenth embodiment of the present
invention, and the writing instrument P of the above fourteenth
embodiment is of a structure in which the writing instrument G of
the seventh embodiment shown in FIG. 10 is provided with an
inter-feeder 25g. The above writing instrument is a writing
instrument of a twin type in which an ink impregnated into an ink
occlusion body 20 in a barrel 10 is fed to a pen tip 40 for
underline and a pen tip 45 for a felt-tip pen which are writing
parts provided at both sides of the barrel 10.
[0137] The ink is fed smoothly and efficiently from the ink
occlusion body 20 via an ink guiding feed 30 having visibility and
the inter-feeder 25 at a pen tip 40 side, and at a pen tip 45 side,
a rear end part of the pen tip 45 is inserted into the ink
occlusion body 20 and brought into contact therewith, whereby the
ink is fed directly from the ink occlusion body 20. The reference
numeral 46 shows a front barrel part molded integrally with the
barrel 10.
[0138] In the above writing instrument P of a twin type, the ink is
consumed at the respective pen tips 40, 45, and a sign of
exhausting the ink in the ink occlusion body 20 is detected by
visually observing the ink guiding feed 30 via a visible part
12.
[0139] The visible part 12, the ink guiding feed 30 and the like
are provided at the pen tip 40 Side in the embodiment described
above. On the contrary, it is allowed that the visible part 12, the
ink guiding feed 30 and the like are provided at the pen tip 45
side and that a rear end part of the pen tip 40 is inserted into
and brought into contact with the ink occlusion body 20, whereby
the ink is fed directly from the ink occlusion body 20.
[0140] It is a matter of course that the writing instrument of the
present invention shall not be restricted to the respective
embodiments 1 to 14 described above and that it can be modified to
various forms as long as the scope of the present invention is not
changed.
[0141] For example, the respective embodiments of the first
embodiment (including the variant example shown in FIG. 4) to the
fourteenth embodiment each described above may suitably be
combined; for example, the third or fourth embodiment may be
applied to the writing instrument of the fifth or sixth embodiment;
the second to fourth embodiments may be applied respectively to the
writing instrument of the seventh embodiment; further, the writing
instrument C of the seventh embodiment may be provided with an
inter-feeder; and in the respective writing instruments A to G of
the respective embodiments of the first to seventh embodiments, a
pen tip feeder for efficiently feeding the ink contained in the ink
guiding feed 30 to the pen tip 40 may be further added separately
or integrally with the pen tip.
[0142] Further, the respective embodiments of the eighth embodiment
(including the variant example shown in FIG. 12) to the thirteenth
embodiment each described above may suitably be combined; for
example, the tenth or eleventh embodiment may be applied to the
writing instruments of the twelfth, thirteenth and fourteenth
embodiments; and in the respective writing instruments H to P of
the tenth to fourteenth embodiments, a pen tip feeder for
efficiently feeding the ink contained in the ink guiding feed 30 to
the pen tip 40 may be further added separately or integrally with
the pen tip.
[0143] The writing instrument of the present invention has a
structure as a scope, in which the ink impregnated into the ink
occlusion body 20 is fed to the pen tip via the ink guiding feed 30
having visibility or the inter-feeder 25 and the ink guiding feed
30 having visibility and in which a sign of exhausting the ink fed
from the ink occlusion body 20 can be detected by visually
observing the ink guiding feed 30 described above via the visible
part 12 formed in the barrel 10. Accordingly, a structure in which
the above scope is not changed shall not specifically be
restricted, and various structures publicly known for writing
instruments can be adopted. The present invention can suitably be
applied to writing instruments of various uses by changing the pen
tip and the kind of the ink according to uses such as a ballpoint
pen, a felt-tip pen, a marking pen, a writing brush pen and the
like.
[0144] Further, the writing instrument may be applied for an
applicator by using a correction liquid, a coating liquid; liquid
toiletries such as cosmetics instead of the ink.
EXAMPLES
[0145] Next, the present invention shall more specifically be
explained with reference to specific examples, but the present
invention shall not be restricted to the following examples. A
surface tension of an ink and the like was measured by a Wilhelmy
method (CBVP-Z type, manufactured by Kyowa Interface Science Co.,
Ltd.), and a viscosity of an ink was measured by means of a
rotational viscometer (TV-20L, manufactured by Tokimec Inc.).
Example 1
Felt-Tip Pen
[0146] A barrel, an ink occlusion body, an ink guiding feed, a pen
tip and an ink composition each having the following constitutions
were used to prepare a felt-tip pen according to FIG. 1 and FIG.
3.
(1) Barrel
[0147] Made of polypropylene, a diameter of a large diameter part:
10 mm, a length of a visible part: 15 mm (the part other than the
visible part was a non-visible part by coloring it), an overall
length: 120 mm
[0148] (2) Ink Occlusion Body
[0149] Constituted from a sliver made of polyethylene terephthalate
(porosity: 80%), a diameter: 9 mm, a length: 60 mm
[0150] (3) Ink Guiding Feed
[0151] Made of PFA (tetrafluoroethylene-perfluoroalkyl vinyl ether
copolymer), an inner diameter: 3 mm, a length: 20 mm, an ink
passage cross-sectional area: about 7 mm.sup.2, a surface tension
(25.degree. C.) of a material itself for the ink guiding feed: 20
mN/m, a length by which a rear end part was inserted into the ink
occlusion body 20: 3 mm
[0152] (4) Pen Tip
[0153] Constituted from a sliver feed of an acryl fiber (porosity:
55%), a length: 15 mm
[0154] (5) Ink Composition (Total Amount: 100% by weight)
TABLE-US-00001 Water soluble dye (C.I. Direct Black-154) 4.5 Water
soluble dye (C.I. Direct Black-19) 1.5 Ethylene glycol 10.0
Glycerin 10.0 pH controlling agent 0.3 Preservative (Proxel GXL)
0.5 Adhesive resin (styrene acrylic acid 3.0 resin, neutralized
with ammonia) Surfactant (Ingen P, manufactured by 0.2 Daiichi
Kogyo Seiyaku Co., Ltd.) Refined water balance
[0155] A surface tension (25.degree. C.) of the ink: 37 mN/m, a
viscosity (25.degree. C.) of the ink: 8 mPas, an amount of the ink
impregnated into the ink occlusion body: 2.5 g.
[0156] In a felt-tip pen A obtained in the constitution described
above, it could be visually observed via a visible part 12 that
after assembling, an ink passed through an ink guiding feed 30, and
then it was found that the ink penetrated into a pen tip 40 and
that an ink discharge amount of the felt-tip pen was almost
constant until the ink was exhausted as was the case with a free
ink type writing instrument and good drawn lines could be
written.
[0157] Writing was continued until the ink impregnated into an ink
occlusion body 20 was exhausted to find that the ink run out from
the ink guiding feed 30, that is, a sign of exhausting the ink fed
from the ink occlusion body 20 could readily and surely be detected
by visually observing the ink guiding feed 30 described above via
the visible part 12 formed in a barrel 10.
[0158] Further, after detecting the exhaustion of the ink from the
ink guiding feed 30, a discharge amount of the ink was suddenly
decreased, and writing became impossible.
Example 2
Felt-Tip Pen
[0159] A barrel, an ink occlusion body, an ink guiding feed, a pen
tip and an ink composition each having the following constitutions
were used to prepare a felt-tip pen according to FIG. 5.
(1) Barrel
[0160] Made of polypropylene, a diameter of a large diameter part:
10 mm, a length of a visible part: 15 mm (the part other than the
visible part was a non-visible part by coloring it), an overall
length: 120 mm
(2) Ink Occlusion Body
[0161] Constituted from a sliver made of polyethylene terephthalate
(porosity: 80%), a diameter: 9 mm, a length: 60 mm
(3) Two Ink Guiding Feeds Having Different Lengths
[0162] i) Made of polypropylene, an inner diameter: 3 mm, a length:
20 mm, an ink passage cross-sectional area: about 7 mm.sup.2, a
surface tension (25.degree. C.) of a material itself for the ink
guiding feed: 31 mN/m, a length by which a rear end part was
inserted into the ink occlusion body 20: 3 mm. [0163] ii) Made of
polypropylene, an inner diameter: 3 mm, a length: 30 mm, an ink
passage cross-sectional area: about 7 mm.sup.2, a surface tension
(25.degree. C.) of a material itself for the ink guiding feed: 31
mN/m, a length by which a rear end part was inserted into the ink
occlusion body 20: 3 mm. [0164] iii) X: 10 mm
(4) Pen Tip
[0165] Constituted from a sliver feed of a polyethylene
terephthalate fiber (porosity: 55%), a length: 15 mm
(5) Ink Composition (Total Amount: 100% by weight)
TABLE-US-00002 Water soluble dye (C.I. Direct Black-154) 5.0
Thiodiethanol 10.0 Glycerin 5.0 Urea 4.0 Surfactant (Dobanox 25N,
manufactured by 0.05 Lion Corporation) Refined water balance
[0166] A surface tension (25.degree. C.) of the ink: 55 mN/m, a
viscosity (25.degree. C.) of the ink: 2 mPas, an amount of the ink
impregnated into the ink occlusion body: 2.5 g.
[0167] In a felt-tip pen B obtained in the constitution described
above, it could be visually observed via a visible part 12 that
after assembling, an ink passed through ink guiding feeds 31, 32,
and then it was found that the ink penetrated into a pen tip 40 and
that good drawn lines could be written as a felt-tip pen.
[0168] Writing was continued until the ink impregnated into the ink
occlusion body 20 was exhausted to find that firstly, the ink run
out from the ink guiding feed 31, that is, a sign of a remaining
amount (90% in the present example) of the ink fed from the ink
occlusion body 20 could readily and surely be detected by visually
observing the ink guiding feed 30 described above via the visible
part 12 formed in a barrel 10. Further, writing was continued to
find that the ink was exhausted from the ink guiding feed 32, that
is, a sign of exhausting the ink fed from the ink occlusion body 20
could readily and surely be detected by visually observing the ink
guiding feed 32 described above via the visible part 12 formed in
the barrel 10. The same evaluation results as in Example 1 were
obtained for the others.
Example 3
Felt-Tip Pen
[0169] A barrel, an ink occlusion body, an ink guiding feed, a pen
tip and an ink composition each having the following constitutions
were used to prepare a felt-tip pen according to FIG. 6.
(1) Barrel
[0170] Made of polypropylene, a diameter of a large diameter part:
10 mm, a length of a visible part: 15 mm (the part other than the
visible part was a non-visible part by coloring it), an overall
length: 120 mm
(2) Ink Occlusion Body
[0171] Constituted from a sliver made of polyethylene terephthalate
(porosity: 80%), a diameter: 9 mm, a length: 60 mm
(3) Ink Guiding Feed
[0172] Made of polypropylene, an inner diameter: 3 mm, a length: 20
mm, an ink passage cross-sectional area: about 7 mm.sup.2, a
surface tension (25.degree. C.) of a material itself for the ink
guiding feed: 31 mN/m, a length by which a rear end part was
inserted into the ink occlusion body 20: 3 mm
(4) Ink-Feeder
[0173] Constituted from a sliver made of polyethylene terephthalate
(porosity: 50%), a diameter: 3 mm, a length: 20 mm
(5) Pen Tip
[0174] Constituted from a sliver feed of an acryl fiber (porosity:
55%), a length: 15 mm
(6) Ink Composition (Total Amount: 100% by weight)
TABLE-US-00003 Carbon black 6.0 Thiodiethanol 15.0 Glycerin 5.0
Urea 5.0 Surfactant (Pluronic PE3100, manufactured 0.03 by BASF
AG.) Refined water balance
[0175] A surface tension (25.degree. C.) of the ink: 54 mN/m, a
viscosity (25.degree. C.) of the ink: 2.5 mPas, an amount of the
ink impregnated into the ink occlusion body: 2.5 g.
[0176] In a felt-tip pen C obtained in the constitution described
above, it could be visually observed via a visible part 12 that
after assembling, an ink passed through an ink guiding feed 33, and
then it was found that the ink penetrated into a pen tip 40 and
that good drawn lines could be written as a felt-tip pen.
[0177] Writing was continued until the ink impregnated into the ink
occlusion body 20 was exhausted to find that the ink run out from
the ink guiding feed 33, that is, a sign of exhausting the ink fed
from the ink occlusion body 20 could readily and surely be detected
by visually observing the ink guiding feed 33 described above via
the visible part 12 formed in a barrel 10. The same evaluation
results as in Example 1 were obtained for the others.
Example 4
Felt-Tip Pen
[0178] A barrel, an ink occlusion body, an ink guiding feed, a pen
tip and an ink composition each having the following constitutions
were used to prepare a felt-tip pen according to FIG. 7.
(1) Barrel
[0179] Made of polypropylene, a diameter of a large diameter part:
10 mm, a length of a visible part: 15 mm (the part other than the
visible part was a non-visible part by coloring it), an overall
length: 120 mm
(2) Ink Occlusion Body
[0180] Constituted from a sliver made of polyethylene terephthalate
(porosity: 80%), a diameter: 8 mm, a length: 60 mm
(3) Ink Guiding Feed
[0181] Made of PFA (tetrafluoroethylene-perfluoroalkyl vinyl ether
copolymer), an inner diameter: 3 mm, a length: 20 mm, an ink
passage cross-sectional area: about 7 mm.sup.2, a surface tension
(25.degree. C.) of a material itself for the ink guiding feed: 20
mN/m, a length by which a rear end part was inserted into the ink
occlusion body 20: 3 mm
(4) Bar-Like Body
[0182] Made of Teflon (trade name), a diameter: 1 mm, a length: 25
mm, white
(5) Pen Tip
[0183] Constituted from a sliver feed of an acryl fiber (porosity:
50%), a length: 15 mm
(6) Ink Composition (Total Amount: 100% by weight)
TABLE-US-00004 Color pigment (C.I. Pigment Blue 15:3) 4.0
Thiodiethanol 5.0 Diethylene glycol 5.0 Isopropyl alcohol 3.0 Urea
3.0 Surfactant (Pluronic PE3100, manufactured 0.03 by BASF AG.)
Refined water balance
[0184] A surface tension (25.degree. C.) of the ink: 55 mN/m, a
viscosity (25.degree. C.) of the ink: 2 mPas, an amount of the ink
impregnated into the ink occlusion body: 2.5 g.
[0185] In a felt-tip pen D obtained in the constitution described
above, it could be visually observed via a visible part 12 that
after assembling, an ink passed through an ink guiding feed 35, and
then it was found that the ink penetrated into a pen tip 40 and
that good drawn lines could be written as a felt-tip pen.
[0186] Writing was continued until the ink impregnated into the ink
occlusion body 20 was exhausted to find that the ink run out from
an ink guiding feed 30, that is, a sign of exhausting the ink fed
from the ink occlusion body 20 could readily and surely be detected
by visually observing a white color of the bar-like body inserted
into the ink guiding feed 35 described above via the visible part
12 formed in a barrel 10. The same evaluation results as in Example
1 were obtained for the others.
Example 5
Ballpoint Pen
[0187] A barrel, an ink occlusion body, an ink guiding feed, a pen
tip and an ink composition each having the following constitutions
were used to prepare a ballpoint pen according to FIG. 9.
(1) Barrel
[0188] Made of polypropylene, a diameter of a large diameter part:
8 mm, a length of a visible part: 15 mm (the part other than the
visible part was a non-visible part by coloring it), an overall
length: 120 mm
(2) Ink Occlusion
[0189] Constituted from a sliver made of polyethylene terephthalate
(porosity: 80%), a diameter: 6 mm, a length: 60 mm
(3) Ink Guiding Feed
[0190] Made of polypropylene, an inner diameter: 3 mm, a length: 20
mm, an ink passage cross-sectional area: about 7 mm.sup.2, a
surface tension (25.degree. C.) of a material itself for the ink
guiding feed: 31 mN/m, a length by which a rear end part was
inserted into an ink occlusion body 20: 3 mm
(4) Pen Tip
[0191] Constituted from a sliver feed of an acryl fiber (porosity:
50%), a length: 15 mm, a ball diameter: 0.5 mm
(5) Ink Composition (Total Amount: 100% by Weight)
TABLE-US-00005 [0192] Water soluble dye (C.I. Direct Black-154) 5.0
Thiodiethanol 10.0 Glycerin 5.0 Urea 4.0 Surfactant (Dobanox 25N,
manufactured by 0.05 Lion Corporation) Refined water balance
[0193] A surface tension (25.degree. C.) of the ink: 55 mN/m, a
viscosity (25.degree. C.) of the ink: 2 mPas, an amount of the ink
impregnated into the ink occlusion body: 2.5 g.
[0194] In a ballpoint pen E obtained in the constitution described
above, it could be visually observed via a visible part 12 that
after assembling, an ink passed through ink guiding feed 30, and
then it was found that the ink penetrated into a pen tip 40 and
that good drawn lines could be written as a ballpoint pen.
[0195] Writing was continued until the ink impregnated into the ink
occlusion body 20 was exhausted to find that the ink run out from
an ink guiding feed 30, that is, a sign of exhausting the ink fed
from the ink occlusion body 20 could readily and surely be detected
by visually observing the ink guiding feed 30 described above, via
the visible part 12 formed in a barrel 10. The same evaluation
results as in Example 1 were obtained for the others.
Example 6
Felt-Tip Pen
[0196] In Example 1 described above, two elements of the ink
occlusion body and the ink composition were changed to an ink
occlusion body and an ink composition (oil-based ink) having the
following constitutions to prepare a felt-tip pen according to FIG.
1 and FIG. 3.
(1) Ink Occlusion Body:
[0197] Constituted from a sliver made of polypropylene (porosity:
80%), a diameter: 9 mm, a length: 60 mm
(2) Ink Composition (Total Amount: 100% by Weight)
TABLE-US-00006 [0198] n-Propyl alcohol 75.0 Laropal A-101
(condensation product of 7.5 aldehyde and urea, manufactured by
BASF AG.) Alresat KM400 (maleic acid resin, 10.0 manufactured by
Hoechst AG.) Victoria Blue BSA (dye, manufactured by 2.5 Zeneca
Co., Ltd.) Rhodamine 6JHSA (dye, manufactured by 2.5 Zeneca Co.,
Ltd.) Flex YELLOW 105 (dye, manufactured by 2.5 Zeneca Co.,
Ltd.)
[0199] A surface tension (25.degree. C.) of the ink: about 22 mN/m,
a viscosity (25.degree. C.) of the ink: about 4 mPas, an amount of
the ink impregnated into the ink occlusion body: 2.5 g.
[0200] In a felt-tip pen A obtained in the constitution described
above, it could be visually observed via a visible part 12 that
after assembling, an ink passed through an ink guiding feed 30, and
then it was found that the ink penetrated into a pen tip 40 and
that an ink discharge amount of the felt-tip pen was almost
constant until the ink was exhausted as was the case with a free
ink type writing instrument and good drawn lines could be
written.
[0201] Writing was continued until the oil-based ink impregnated
into an ink occlusion body 20 was exhausted to find that the
oil-based ink run out from the ink guiding feed 30, that is, a sign
of exhausting the ink fed from the ink occlusion body 20 could
readily and surely be detected by visually observing the ink
guiding feed 30 described above via the visible part 12 formed in a
barrel 10.
[0202] Further, after detecting the exhaustion of the ink from the
ink guiding feed 30, a discharge amount of the ink was suddenly
decreased, and writing became impossible.
Example 7
Felt-Tip Pen
[0203] A barrel, an ink occlusion body, an ink guiding feed, an
inter-feeder, a pen tip and an ink composition each having the
following constitutions were used to prepare a felt-tip pen
according to FIG. 11.
(1) Barrel
[0204] Made of polypropylene, a diameter of a large diameter part:
10 mm, a length of a visible part: 15 mm (the part other than the
visible part was a non-visible part by coloring it), an overall
length: 120 mm
(2) Ink Occlusion Body
[0205] Constituted from a sliver made of polyethylene terephthalate
(porosity: 80%), a diameter: 9 mm, a length: 60 mm
(3) Ink Guiding Feed
[0206] Made of PFA (tetrafluoroethylene-perfluoroalkyl vinyl ether
copolymer), an inner diameter: 3 mm, a length: 20 mm, an ink
passage cross-sectional area: about 7 mm.sup.2, a surface tension
(25.degree. C.) of a material itself for the ink guiding feed: 20
mN/m, a length by which a rear end part was inserted into the ink
occlusion body 20: 3 mm
(4) Inter-Feeder
[0207] Constituted from a sliver made of acryl (porosity: 55%), a
diameter: about 3 mm, a length: 20 mm, a form of an inserted part:
cylindrical, a form of acute angle part: conical
(5) Pen Tip
[0208] Constituted from a sliver feed of an acryl fiber (porosity:
50%), a length: 15 mm
(5) Ink Composition (Total Amount: 100% by Weight)
TABLE-US-00007 [0209] Water soluble dye (C.I. Direct Black-154) 4.5
Water soluble dye (C.I. Direct Black-19) 1.5 Ethylene glycol 10.0
Glycerin 10.0 pH controlling agent 0.3 Preservative (Proxel GXL)
0.5 Adhesive resin (styrene acrylic acid 3.0 resin, neutralized
with ammonia) Surfactant (Ingen P, manufactured by 0.2 Daiichi
Kogyo Seiyaku Co., Ltd.) Refined water balance
[0210] A surface tension (25.degree. C.) of the ink: 37 mN/m, a
viscosity (25.degree. C.) of the ink: 8 mPas, an amount of the ink
impregnated into the ink occlusion body: 2.5 g.
[0211] In a felt-tip pen obtained in the constitution described
above, it could be visually observed via a visible part 12 that
after assembling, an ink passed through an ink guiding feed 30, and
then it was found that the ink penetrated into a pen tip 40 and
that an ink discharge amount of the felt-tip pen was almost
constant until the ink was exhausted as was the case with a free
ink type writing instrument and good drawn lines could be
written.
[0212] Writing was continued until the ink impregnated into the ink
occlusion body 20 was exhausted to find that the ink run out from
the ink guiding feed 30, that is, a sign of exhausting the ink fed
from the ink occlusion body 20 could readily and surely be detected
by visually observing the ink guiding feed 30 described above via
the visible part 12 formed in a barrel 10.
[0213] Further, after detecting the exhaustion of the ink from the
ink guiding feed 30, a discharge amount of the ink was suddenly
decreased, and writing became impossible.
Example 8
Felt-Tip Pen
[0214] A barrel, an ink occlusion body, an ink guiding feed, an
inter-feeder, a pen tip feed, a pen tip and an ink composition each
having the following constitutions were used to prepare a felt-tip
pen according to FIG. 13.
(1) Barrel
[0215] Made of polypropylene, a diameter of a large diameter part:
10 mm, a length of a visible part: 15 mm (the part other than the
visible part was a non-visible part by coloring it), an overall
length: 120 mm
(2) Ink Occlusion Body
[0216] Constituted from a sliver made of polyethylene terephthalate
(porosity: 80%), a diameter: 9 mm, a length: 60 mm
(3) Ink Guiding Feed
[0217] Made of polypropylene, an inner diameter: 3 mm, a length: 20
mm, an ink passage cross-sectional area: about 7 mm.sup.2, a
surface tension (25.degree. C.) of a material itself for the ink
guiding feed: 31 mN/m, a length by which a rear end part was
inserted into an ink occlusion body 20: 3 mm
(4) Inter-Feeder
[0218] Constituted from a sliver made of acryl (porosity: 55%), a
diameter: about 3 mm, a length: 30 mm, a form of an inserted part:
cylindrical, a form of acute angle part: conical
(5) Pen Tip Feeder
[0219] Constituted from a sliver made of acryl (porosity: 50%), a
diameter: about 3 mm, a length: 8 mm, a form of an inserted part:
cylindrical, a form of acute angle part: conical, a length: 15
mm
(6) Pen Tip
[0220] Constituted from a sliver feed of polyethylene terephthalate
(porosity: 50%), a length: 15 mm
(7) Ink Composition (Total Amount: 100% by Weight)
TABLE-US-00008 [0221] Water soluble dye (C.I. Direct Black-154) 5.0
Thiodiethanol 10.0 Glycerin 5.0 Urea 4.0 Surfactant (Dobanox 25N,
manufactured by 0.05 Lion Corporation) Refined water balance
[0222] A surface tension (25.degree. C.) of the ink: 55 mN/m, a
viscosity (25.degree. C.) of the ink: 2 mPas, an amount of the ink
impregnated into the ink occlusion body: 2.5 g.
[0223] In a felt-tip pen obtained in the constitution described
above, it could be visually observed via a visible part 12 that
after assembling, an ink passed through an ink guiding feed 30, and
then it was found that the ink penetrated into a pen tip 40 via a
pen tip feeder 28 and that an ink discharge amount of the felt-tip
pen was almost constant until the ink was exhausted as was the case
with a free ink type writing instrument and good drawn lines could
be written.
[0224] Writing was continued until the ink impregnated into the ink
occlusion body 20 was exhausted to find that the ink run out from
the ink guiding feed 30, that is, a sign of exhausting the ink fed
from the ink occlusion body 20 could readily and surely be detected
by visually observing the ink guiding feed 30 described above via
the visible part 12 formed in a barrel 10.
[0225] Further, after detecting the exhaustion of the ink from the
ink guiding feed 30, a discharge amount of the ink was suddenly
decreased, and writing became impossible.
Example 9
Felt-Tip Pen
[0226] A barrel, an ink occlusion body, an ink guiding feed,
inter-feeders, a pen tip and an ink composition each having the
following constitutions were used to prepare a felt-tip pen
according to FIG. 14.
(1) Barrel
[0227] Made of polypropylene, a diameter of a large diameter part:
10 mm, a length of a visible part: 15 mm (the part other than the
visible part was a non-visible part by coloring it), an overall
length: 120 mm
(2) Ink Occlusion Body
[0228] Constituted from a sliver made of polyethylene terephthalate
(porosity: 80%), a diameter: 9 mm, a length: 60 mm
(3) Ink Guiding Feeds
[0229] i) Long ink guiding feed: made of polypropylene, an inner
diameter: 3 mm, a length: 35 mm, an ink passage cross-sectional
area: about 7 mm.sup.2, a surface tension (25.degree. C.) of a
material itself for the ink guiding feed: 31 mN/m, a length by
which a rear end part was inserted into an ink occlusion body 20:
15 mm. [0230] ii) Short ink guiding feed: made of polypropylene, an
inner diameter: 3 mm, a length: 25 mm, an ink passage
cross-sectional area: about 7 mm.sup.2, a surface tension
(25.degree. C.) of a material itself for the ink guiding feed: 31
mN/m, a length by which a rear end part was inserted into the ink
occlusion body 20: 5 mm.
(4) Inter-Feeder
[0230] [0231] i) Long feeder: constituted from a sliver made of
polyethylene terephthalate (porosity: 55%), a diameter: 3 mm, a
length: 20 mm, a form: cylindrical [0232] ii) Short feeder:
constituted from a sliver made of polyethylene terephthalate
(porosity: 55%), a diameter: 3 mm, a length: 10 mm, a form:
cylindrical [0233] iii) X.sub.1: 10 mm, X.sub.2: 15 mm
(5) Pen Tip
[0234] Constituted from a sliver feed of an acryl fiber (porosity:
50%), a length: 15 mm
(6) Ink Composition (Total Amount: 100% by Weight)
TABLE-US-00009 [0235] Carbon black 6.0 Thiodiethanol 15.0 Glycerin
5.0 Urea 5.0 Surfactant (Pluronic PE3100, manufactured 0.03 by BASF
AG.) Refined water balance
[0236] A surface tension (25.degree. C.) of the ink: 54 mN/m, a
viscosity (25.degree. C.) of the ink: 2.5 mPas, an amount of the
ink impregnated into the ink occlusion body: 2.5 g.
[0237] In a felt-tip pen obtained in the constitution described
above, it could be visually observed via a visible part 12 that
after assembling, an ink passed through ink guiding feeds 31, 32,
and then it was found that the ink penetrated into a pen tip 40 and
that good drawn lines could be written as a felt-tip pen.
[0238] Writing was continued until the ink impregnated into the ink
occlusion body 20 was exhausted to find that firstly, the ink run
out from the ink guiding feed 31, that is, a sign of a remaining
amount (70% in the present example) of the ink fed from the ink
occlusion body 20 could readily and surely be detected by visually
observing the ink guiding feed 31 described above via the visible
part 12 formed in a barrel 10. Further, writing was continued to
find that the ink run out from the ink guiding feed 32, that is, a
sign of exhausting the ink fed from the ink occlusion body 20 could
readily and surely be detected by visually observing the ink
guiding feed 32 described above via the visible part 12 formed in
the barrel 10. The same evaluation results as in Example 1 were
obtained for the others.
Example 10
Felt-Tip Pen
[0239] A barrel, an ink occlusion body, an ink guiding feed, an
inter-feeder, a pen tip, a bar-like body and an ink composition
each having the following constitutions were used to prepare a
felt-tip pen according to. FIG. 15.
(1) Barrel
[0240] Made of polypropylene, a diameter of a large diameter part:
10 mm, a length of a visible part: 15 mm (the part other than the
visible part was a non-visible part by coloring it), an overall
length: 120 mm
(2) Ink Occlusion Body
[0241] Constituted from a sliver made of polyethylene terephthalate
(porosity: 80%), a diameter: 8 mm, a length: 60 mm
(3) Inter-Feeder
[0242] Constituted from a sliver made of acryl (porosity: 55%), a
diameter: about 3 mm, a length: 30 mm, a form of an inserted part:
cylindrical, a form of acute angle part: conical
(4) Ink Guiding Feed
[0243] Made of PFA (tetrafluoroethylene-perfluoroalkyl vinyl ether
copolymer), an inner diameter: 3 mm, a length: 20 mm, an ink
passage cross-sectional area: about 7 mm.sup.2, a surface tension
(25.degree. C.) of a material itself for the ink guiding feed: 20
mN/m, a length by which a rear end part was inserted into the ink
occlusion body 20: 3 mm
(5) Bar-Like Body
[0244] Made of Teflon (trade name), a diameter: 1 mm, a length: 25
mm, white
(6) Pen Tip
[0245] Constituted from a sliver feed of an acryl fiber (porosity:
50%), a length: 15 mm
(7) Ink Composition (Total Amount: 100% by weight)
TABLE-US-00010 Color pigment (C.I. Pigment Blue 15:3) 4.0
Thiodiethanol 5.0 Diethylene glycol 5.0 Isopropyl alcohol 3.0 Urea
3.0 Surfactant (Pluronic PE3100, manufactured 0.03 by BASF AG.)
Refined water balance
[0246] A surface tension (25.degree. C.) of the ink: 55 mN/m, a
viscosity (25.degree. C.) of the ink: 2 mPas, an amount of the ink
impregnated into the ink occlusion body: 2.5 g.
[0247] In a felt-tip pen obtained in the constitution described
above, it could be visually observed via a visible part 12 that
after assembling, an ink passed through an ink guiding feed 35, and
then it was found that the ink penetrated into a pen tip 40 and
that good drawn lines could be written as a felt-tip pen.
[0248] Writing was continued until the ink impregnated into the ink
occlusion body 20 was exhausted to find that the ink run out from
an ink guiding feed 30, that is, a sign of exhausting the ink fed
from the ink occlusion body 20 could readily and surely be detected
by visually observing a white color of the bar-like body inserted
into the ink guiding feed 35 described above via the visible part
12 formed in a barrel 10. The same evaluation results as in Example
1 were obtained for the others.
Example 11
Ballpoint Pen
[0249] A barrel, an ink occlusion body, an ink guiding feed, an
inter-feeder, a pen tip and an ink composition each having the
following constitutions were used to prepare a felt-tip pen
according to FIG. 17.
(1) Barrel
[0250] Made of polypropylene, a diameter of a large diameter part:
8 mm, a length of a visible part: 15 mm (the part other than the
visible part was a non-visible part by coloring it), an overall
length: 120 mm
(2) Ink Occlusion Body
[0251] Constituted from a sliver made of polyethylene terephthalate
(porosity: 80%), a diameter: 6 mm, a length: 60 mm
(3) Inter-Feeder
[0252] Constituted from a sliver made of polyethylene terephthalate
(porosity: 55%), a diameter: 3 mm, a length: 20 mm, a form of an
inserted part: cylindrical, a form of an acute angle part:
conical
(4) Ink Guiding Feed
[0253] Made of polypropylene, an inner diameter: 3 mm, a length: 20
mm, an ink passage cross-sectional area: about 7 mm.sup.2, a
surface tension (25.degree. C.) of a material itself for the ink
guiding feed: 31 mN/m, a length by which a rear end part was
inserted into an ink occlusion body 20: 3 mm
(5) Pen Tip
[0254] Made of stainless steel, a length: 10 mm, a ball diameter:
0.5 mm
(6) Ink Composition (Total Amount: 100% by Weight)
TABLE-US-00011 [0255] Water soluble dye (C.I. Direct Black-154) 5.0
Thiodiethanol 10.0 Glycerin 5.0 Urea 4.0 Surfactant (Dobanox 25N,
manufactured by 0.05 Lion Corporation) Refined water balance
[0256] A surface tension (25.degree. C.) of the ink: 55 mN/m, a
viscosity (25.degree. C.) of the ink: 2 mPas, an amount of the ink
impregnated into the ink occlusion body: 2.5 g.
[0257] In a ballpoint pen obtained in the constitution described
above, it could be visually observed via a visible part 12 that
after assembling, an ink passed through an ink guiding feed 30, and
then it was found that the ink penetrated into a pen tip 40 and
that good drawn lines could be written as a felt-tip pen.
[0258] Writing was continued until the ink impregnated into the ink
occlusion body 20 was exhausted to find that the ink run out from
the ink guiding feed 30, that is, a sign of exhausting the ink fed
from the ink occlusion body 20 could readily and surely be detected
by visually observing the ink guiding feed 30 described above via
the visible part 12 formed in a barrel 10. The same evaluation
results as in Example 1 were obtained for the others.
Example 12
Felt-Tip Pen
[0259] In Example 7 described above, two elements of the ink
occlusion body and the ink composition were changed to an ink
occlusion body and an ink composition (oil-based ink) having the
following constitutions to prepare a felt-tip pen according to FIG.
11.
(1) Ink Occlusion Body:
[0260] Constituted from a sliver made of polyethylene terephthalate
(porosity: 80%), a diameter: 9 mm, a length: 60 mm
(2) Ink Composition (Total Amount: 100% by Weight)
TABLE-US-00012 [0261] n-Propyl alcohol 75.0 Laropal A-101
(condensation product of 7.5 aldehyde and urea, manufactured by
BASF AG.) Alresat KM400 (maleic acid resin, 10.0 manufactured by
Hoechst AG.) Victoria Blue BSA (dye, manufactured by 2.5 Zeneca
Co., Ltd.) Rhodamine 6JHSA (dye, manufactured by 2.5 Zeneca Co.,
Ltd.) Flex YELLOW 105 (dye, manufactured by 2.5 Zeneca Co.,
Ltd.).
[0262] A surface tension (25.degree. C.) of the ink: about 22 mN/m,
a viscosity (25.degree. C.) of the ink: about 4 mPas, an amount of
the ink impregnated into the ink occlusion body: 2.5 g.
[0263] In a felt-tip pen obtained in the constitution described
above, it could be visually observed via a visible part 12 that
after assembling, an ink passed through an ink guiding feed 30, and
then it was found that the ink penetrated into a pen tip 40 and
that an ink discharge amount of the felt-tip pen was almost
constant until the ink was exhausted as was the case with a free
ink type writing instrument and good drawn lines could be
written.
[0264] Writing was continued until the oil-based ink impregnated
into an ink occlusion body 20 was exhausted to find that the ink
run out from the ink guiding feed 30, that is, a sign of exhausting
the ink fed from the ink occlusion body 20 could readily and surely
be detected by visually observing the ink guiding feed 30 described
above via the visible part 12 formed in a barrel 10.
[0265] Further, after detecting the exhaustion of the ink from the
ink guiding feed 30, a discharge amount of the ink was suddenly
decreased, and writing became impossible.
INDUSTRIAL APPLICABILITY
[0266] According to the present invention, provided is a writing
instrument in which an ink impregnated into an ink occlusion body
in a barrel is fed to a pen tip in a writing part, wherein a sign
of exhausting the ink can readily and surely be detected by a
simple structure; an ink discharge amount is almost constant until
the ink is exhausted as is the case with a free ink type writing
instrument, and good drawn lines can be written.
[0267] Further, in a writing instrument in which an ink impregnated
into an ink occlusion body is fed to an ink guiding feed via an
inter-feeder, provided is a writing instrument in which an ink
impregnated into an ink occlusion body can more efficiently and
smoothly be introduced into an ink guiding feed.
* * * * *