Writing instrument barrel and method of forming a writing instrument

An writing instrument having an elongated tubular body formed from a thin sheet of material being rolled upon itself. A marking substance positioned within a bore of the body is prevented from leaking through the body by the application of a coating to at least one side of the sheet so that a lining is formed in the bore.

BACKGROUND OF THE INVENTION 
FIELD OF THE INVENTION 
This invention relates to writing instruments and more particularly, this 
invention relates to the barrel portion of a writing instrument and a 
method of constructing a writing instrument. 
DISCUSSION OF THE RELATED ART 
In the past, writing instruments, such as pencils, have been made by 
winding a sheet material around a solid core such as a graphite 
composition commonly known as lead or crayon. Other similar instruments 
have been made using a wax based substance such as those used for 
so-called china markers where the sheet material used for wrapping the 
marking material could be peeled away or sharpened with a knife to 
continually expose new marking material. These types of marking or writing 
instruments have been known and are disclosed in, for example, U.S. Pat. 
No. 2,469,049 to Miller. 
However, none of these prior writing instruments are suitable for use with 
a marking or writing material in a liquid form such as is used in ink pens 
and felt tip markers. Previously, the only way to accommodate such a 
writing material was to provide a separate structural container such as a 
cartridge or tubular shaped container, typically made of plastic or metal. 
The novel writing instrument according to the present invention obviates 
the disadvantages encountered in the prior art and discloses an instrument 
which is easy to manufacture and efficient to use, which eliminates 
unnecessary structure required by prior art devices. The instrument 
incorporates many features including a sheet of material which may have a 
lining which avoids the need for providing separate conventional ink 
cartridges or inserts. 
SUMMARY OF THE INVENTION 
The present invention relates to a writing instrument having an elongated 
tubular barrel which is formed by rolling a thin sheet upon itself thereby 
forming an inner bore therethrough. The material of which the barrel is 
constructed is preferably a fibrous material such as paper. A lining may 
be applied to the thin sheet to prevent the writing substance from leaking 
therethrough and a writing tip is provided in communication with the 
writing substance. Coupling means such as, for example, friction fitting, 
adhesives or the like are provided on the writing tip for coupling to a 
first end of the elongated barrel. The coupling means may include, for 
example, a tapered writing substance receiving end such that when the 
writing tip is inserted into the opening at the first end, an interference 
or friction fit holds the writing tip in place. An opening at the other 
end of the elongated barrel is sealed by any suitable sealing means, such 
as, for example, a vented plug inserted in the opening. 
The present invention further relates to a method for forming a writing 
instrument by applying a coating to a portion of at least one side of a 
thin, sheet material, drying the coating, rolling the sheet material upon 
itself to form an elongated tubular barrel having an inner wall defining a 
longitudinal bore therethrough, such that the inner wall is lined with the 
coating, inserting a writing tip into the bore at a first end of the 
elongated tubular barrel, and inserting a sealing means into the bore at a 
second end of the elongated tubular barrel. 
An advantage of the above described writing instrument of the present 
invention is that the writing substance is supplied directly to the body 
so that additional process steps of making and filling separate cartridges 
with a writing substance and then inserting those cartridges are avoided.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Referring now to the drawings, wherein like reference numerals designate 
identical or corresponding parts throughout the several views, and more 
particularly to the embodiment of the invention illustrated in FIGS. 1-4, 
writing instrument 10 is illustrated having a barrel shown as elongated 
tubular body 12 formed as a result of thin sheet material 14 being rolled 
upon itself. Sheet 14 may be any suitable material, preferably for 
example, cellulosic paper or any non-woven paper material. Inner wall 16 
is thereby formed defining longitudinal bore 18. Writing tip 20 having 
writing substance receiving end 22 and writing substance delivery end 24 
is securely coupled to elongated tubular body 12 at opening 26 of first 
end 28. Writing tip 20 may be coupled to elongated tubular body 12 by any 
suitable means such as, for example, by interference fit resulting from 
writing substance receiving end 22 having a diameter slightly larger than 
that of opening 26. Other suitable mounting means may obviously be 
substituted therefor. 
A writing substance, for example, ink 30 is contained in longitudinal bore 
18. While the generic term "ink", for the purposes used in this 
description, is used to describe the writing substance, it should be 
understood that the term "ink" includes: water based inks or solvent based 
inks, e.g., glycol based or glycol ether based inks. It is within the 
scope of the present invention that ink 30 may be omitted and supplied to 
longitudinal bore 18 at a later time by a separate supplier. In such an 
embodiment, writing instrument 10 could be shipped without ink and 
separate sealing means such as, for example, vented plug 36, could be 
provided for insertion after longitudinal bore 18 is filled with ink 30. 
Ink 30 may be delivered to longitudinal bore 18 by any suitable means such 
as, for example, by injection. Vented plug 36 is then inserted in opening 
34 at second end 32 of elongated tubular body 18. 
Thin sheet material 14 has two substantially parallel edges 38 and 40 so 
that when thin sheet material 14 is rolled upon itself to form elongated 
tubular body 18, flat ends 42 and 44 are formed. Prior to rolling, sheet 
material 14 may have graphics or text pre-printed thereon such that when 
tubular body 18 is formed the graphics or text will be visible. Such 
printing may include slogans, symbols, and organization logos, among 
others. 
Furthermore, it is contemplated that sheet material 14 may be embossed or 
coated on what will become its outer surface to provide a textured surface 
which enhances the grip and feel of the writing instrument. The addition 
of the textured surface to the sheet material 14 also reduces the amount 
of sheet material necessary to construct the writing instrument. The 
coating of embossed material may be any suitable coating which is flexible 
to permit rolling of sheet material 14. 
Referring now to FIG. 3, which shows thin sheet material 14 of the present 
invention having lining means such as, for example, coating 48 which could 
be made of a typical polymeric lining material. The lining preferably 
contains components that maintain the liquid inks in body 18 while being 
compatible with the main carrier component of the ink. For example, 
polyethylene and polypropylene coating materials may also be used. Coating 
48 is applied to one side of sheet material 14 so that when thin sheet 
material 14 is rolled upon itself lining 17 is formed along inner wall 16 
(FIG. 2) of elongated tubular body 12. Coating 48 may be applied in a 
strip or may cover any length of the side it is applied to. By providing 
such a barrier, ink 30 (FIG. 2) is prevented from leaking through thin 
sheet material 14. 
Referring now to FIG. 4, coating 48 is shown applied to thin sheet material 
14. Any suitable known application method may be used to apply coating 48, 
for example, spreading or spraying with subsequent drying taking place 
either naturally or by known drying means. Coating 48 is preferably a thin 
pliable layer, therefore allowing for rolling of thin sheet material 14. 
It is within the scope of the present invention that coating 48 may also 
serve as an adhesive, holding thin sheet material 14 in its rolled 
position. Alternatively, any conventional suitable adhesive means may be 
used, if needed, to retain the shape of elongated tubular body 50. For 
example, adhesives of the muselage or starch type may also be used. 
Referring now to the embodiment of the invention illustrated in FIG. 5, 
wherein elongated tubular body 50 is formed from thin sheet material 52 
having one tapered edge 54 and one straight edge 56. Conical end 58 is 
formed at the tapered edge side 54 of thin sheet material 52 as the 
material is rolled upon itself. Vented plug 36 is inserted in the fiat end 
side 56 of elongated tubular body 50. Conical end cap 62 may be removably 
fitted over conical end 58. Alternatively, conical end cap 62 may be 
omitted. A writing tip such as, for example, ball point tip 64 is coupled 
to elongated tubular body 50 by coupling means on writing substance 
receiving end 22 in opening 66. The coupling means on writing substance 
receiving end 22 of ball point tip 64 may be of any suitable means such 
as, for example, by interference fit resulting from writing substance 
receiving end 22 having a diameter slightly larger than that of opening 
66. 
Referring now to the embodiment of the invention illustrated in FIG. 6, 
writing instrument 68 is shown having two writing tips 70 and 72. Conical 
ends 74 and 76 for receiving writing tips 70 and 72 are formed from thin 
sheet material 78, with substantially non-parallel tapered edges 80 and 
82, being rolled upon itself. Inner wall 16 is shown surrounding porous 
ink-retainers 84 and 86 and barrier 88. Porous ink retainers 84 and 86 may 
be of any suitable known felt-marker types. Barrier 88 may be any suitable 
sealing means such as, for example, a cylindrical plug or the like made of 
rubber. Barrier 88 provides a break between porous ink retainers 84 and 86 
to prevent the flow of ink therebetween. Sleeve 90 may be provided to 
cover body 68 and may be slid over body 68 or shrink fitted by, for 
example, heat shrinking or similar known processes. Additionally, sleeve 
90 may be provided with pre-printed text and/or graphics including 
messages, slogans, organization or individual names, symbols or the like. 
Such printing and graphics may be arranged so that the same are readily 
visible on the exterior of the writing instrument. A vent hole 91 may be 
provided on both sides adjacent barrier 88 to facilitate the flow of ink. 
Referring now to FIG. 7, thin sheet material 78 is shown with a lining 
material such as, for example, coating 48 applied along broad end 92. Thin 
sheet material 78 has tapered edges 80 and 82 for forming conical ends 74 
and 76 (as seen in FIG. 6). Coating 48 may be applied to broad end 92 in a 
width corresponding to at least one circumference of bore 94 to assure 
full coverage of inner wall 16. The width of coating 48 may, however, be 
any multiple greater than the circumference of inner wall 16 to provide 
additional protection against leakage of ink 30. 
While the invention has been particularly shown and described with 
reference to the preferred embodiments, it will be understood by those 
skilled in the art that various modifications in form and detail may be 
made therein without departing from the scope and spirit of the invention. 
Accordingly, modifications such as those suggested above, but not limited 
thereto, are to be considered within the scope of the invention.