Note: Descriptions are shown in the official language in which they were submitted.
2~76359
REINFORCED EXPANDABLE FOLD~R
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to paper
office supplies, and, in particular, to expandable
folders having reinforced sides, corners, and edges
for making the file stronger and more durable.
2. Description of the Prior Art
Expandable folders are a necessary tool in
the modern office or business and are also commonly
used in homes and schools. These folders are
typically constructed of rectangular front and rear
panel members having accordion-like folds along the
bottom and sides, commonly called gussets, which allow
the folder to expand from front to back. The folders
are shipped and stored in their compact state. When
put into use, the gussets allow the folder to expand
gradually as the folder becomes filled with documents,
papers or other items.
A typical five piece construction is used
for many expandable folders. This construction
includes first front and rear panel members and a
combination side and bottom gusset attached thereto,
with second front and rear panel members attached to
the first front and rear panel members, respectively.
Typically, the gusset ends are secured between the
first and second panel members.
These expandable folders are often filled
(or overfilled) with documents until the gussets are
completely extended and no additional documents can be
placed in the folder. ~owever, filling an expandable
folder in this manner often leads to premature failure
of the folder due to tearing at certain critical or
highly stressed locations. These critical locations
207~3~9
are most commonly at the point of intersection of the
gusset with the front and rear panel members, at the
corners of the folder, along th~ top edge of the
gusset, and in the gusset itself.
Fully expanded folders usually tear at the
point of intersection of the gusset with the front and
rear panel m~mbers because when these expanded folders
are subsequently looked through to locate a particular
document, the searcher often tries to expand the
folder further in order to see and retrieve the
documents stored therein. Also, when the retrieved
document must be returned to the folder, the searcher
will again stretch the folder to make room so that the
document may be easily placed therein. However,
because the gusset is already fully expanded, the only
way for the folder to expand further is for the folder
to tear at the point where the gussets are joined to
the front and rear panel members of the folder.
A fully expanded folder is also relatively
heavy, and this weight contributes to failure of the
folder in variety of ways. For instance, the folders
are often picked up by only the front or rear panel
member, which causes the panel member to completely
tear away from the gusset. Further, when a fully
expanded folder is repeatedly placed on a desk or
tabletop, the rubbing of the corners, sides and bottom
of the folder on the tabletop surface causes these
areas of the folder to fray or wear away. This
fraying and wearing away detracts from the neat
appearance the folders should have, further weakens
the folder and can cause the loss of small items
stored therein. Finally, when a full folder is
dropped, the folder will burst or split along the seam
between the gusset and front or rear panel members,
scattering the folder or contents around the place of
impact.
_ 3 _ 2~ 76~59
Expandable folders are also normally stor~d
on shelves with their front and rear faces
perpendicular to the length of the shelf. When these
folders are retrieved, fingers are usually placed over
the top edge of the gusset so that the folder can be
pulled off the shelf. However, because the fully
expanded folder is relatively heavy, pulling the
folder in this manner often leads to separation of the
gusset from the front and rear panel members.
Further, the fingers usually pull khe folder from the
same place on the gusset over and over again. Over
time, dirt and sweat will accumulate on the gusset,
thereby fraying and weakening the gusset and causing
the gusset to unexpectedly tear when the folder is
retrieved.
These folders often become wet during use,
either by being exposed to rain or snow during
transport from one location to another, or when water
or beverages such as coffee, tea, or soda are
accidentally spilled on them, or due to moisture in
the air when the folder is stored. When these folders
become moist or wet, they weaXen considerably and are
very susceptible to tearing. Further, the wet folders
become deformed, weakened and deteriorate rapidly when
they become dry, and are also very susceptible to
tearing in this condition.
Finally, these folders are often identified
by pressure-sensitive adhesive labels attached to the
front or rear panel member. However, when it is
desired to remove these labels, the folders often
become disfigured due to the inability to separate the
adhesive on the label from the fibers in the panel
members. Thus, these folders are often discarded
simply because they no longer have a neat appearance.
The applicants have identified the above
problems and have established that a need exists for
an expandable folder that solves such problems. In
_ 4 _ 2~763~
particular, there is a need for an expandable folder
of superior strength that is durable, will not fail
when it is filled to capacity, is resistant to
liquids, and which will maintain a neat, sturdy
appearance.
~U~MARY OF TXE INVENq~ION
The present invention provides an expandable
folder which includes reinforcing material to increase
the strength and durability of the folder. This
folder comprises a front panel member having first and
second surfaces, opposed sides and a bottom, a rear
panel member having first and second surfaces, opposed
sides and a bottom, and an expandable gusset member
having a top, bottom, opposed side gussets, and two
corners. The bottom and opposed side gussets of the
gusset member connect peripheral portions of the
bottom of the front and rear panel memb~rs and at
least a portion of the sides thereof so that the first
surfaces of the panel members face each other to
define the inner boundaries of the folder, which form
a cavity for receiving file materials.
The gusset member comprises a sheet ha~ing a
plurality of accordion-like folds, preferably, with
the terminal folds of the sheet being wider than the
other folds. These terminal folds are connected to
the front and rear panel members to enhance the
connection therebetween.
Interior reinforcing means may be applied to
the first surfacQs of the front and rear panel members
in order to prevent separation of the front and rear
panel members from the gusset members when the folder
is used. Preferably, the interior reinforcing means
is positioned adjacent to at least part of the
connection between the sides of the gusset member and
panel member peripheral portions.
- 5 - 2~7~35~
Reinforcing means may also be applied to the
corners of the gusset member. This reinforcing means
extends along the corner and a portion of the side and
bottom of the gusset member to enhance the wear
resistance of the folder.
In one embodimsnt, reinforcing material is
applied across a portion of each side gusset of the
folder and onto a portion of the front and rear panels
to strengthen and increase the connection of each side
gusset to the panel members and the durability of the
folder.
In another embodiment, the side gusset
members include a top edge, and the reinforcing
material is applied in the form of a band to the side
gusset members at the top edge thereof.
The reinforcing material may be affixed to
the outer surface of the side gussets and onto the
outer surfaces of the panel members of the folder,
preferably in the form of a band which extends across
the side gusset members and the outer surfaces of the
panel members to completely engage the outside
perimeter of the entire folder. If desired, the
reinforcing material can completely cover the gusset
member and portions of the panel members.
Alternatively, the reinforcing material may
be affixed to the inner surface of the side gusset
member and onto at least a portion of the inner
surfaces of the panel members. Again, the reinforciny
material may be applied in the form of a band which
extends across the side gusset members and the inner
surfaces of the panel members to completely engage the
inside perimeter of the entire folder, or to
completely cover the gusset member and portions of the
panel members.
The reinforcing material may also be used in
the form of reinforcing strips which are placed
adjacent the top edge of the side gusset member at
- 6 - 2~7~359
each connection of the side gusset member to the front
and rear panel members. Preferably, a first
reinforcing strip is affixed to each outer layer of
the front panel member, extending at an angle over the
top edge of the adjacent side gusset member and onto
the inner layer of the front panel member; and a
second reinforcing strip is af~ixed to each outer
layer of the rear panel member, extendinc; at ~n angle
over the top edge of the adjacent side gusset member
and onto the inner layer of the rear panel member.
These reinforcing strips should extend onto the panel
members beyond the width of the terminal ends of the
gusset connected thereto. Also, these strips may
extend over the side gusset members at any angle
betwaen 30 and 60 degrees.
Another aspect of the present invention
relates to an expandable folder that has reinforcing
means applied to the top edge of the side gusset
members, which may also be applied to the front and
rear panel members, for providing resistance against
tearing of the top edge of the side gusset members, as
well as resistance to separation of the side gusset
members from the front and rear panel members when the
folder is used.
One type of such reinforcing means may be
prepared by folding the top edge of each side gusset
member onto itself to form a double layer of material.
If desired, each folded top edge may be secured to the
side gusset member with an adhesive. Alternatively,
the reinforcing means may be a strip of reinforcing
material which extends over the top edge of each side
gusset member and onto a portion of each side thereof.
In yet anothar embodiment, each side gusset
member comprises a multiple layer composite structure
and the reinforcing means is prepared by folding the
top edge of each side gusset member onto itself and,
2~7~9
-- 7
if desired, secured with an adhesive to form a double
multiple layer construction.
Alternatively, the terminal end portions of
each side gusset member and the applied reinforcing
means described above do not have to be secured or
attached to each other. In this arrangement, multiple
end portions are provided at each end of the side
gusset member and each may be attached to a different
panel member surface. Also, more than one terminal
end portion may be applied to one panel member
surface.
Another embodiment of the present invention
relates to reinforcing means which is applied upon the
peripheral portions of the front and rear panel
members, wherein the gusset member is attached to the
reinforcing means to enhance the tear resistance
between the connection of the gusset member an the
panel members.
This reinforcing means preferably comprises
a band of reinforcing material which is applied to a
portion of the sides of the outer surfaces of the
front and rear panel members and is at least as wide
as the terminal end portions of the gusset member.
Advantageously, the reinforcing means may also be a
strip of reinforcing material on each panel member
which extends from the bottom to a location above the
point of attachment of the gusset member, and, if
desired, to substantially cover the entire outer
surface of each panel member.
For the preceding embodiments, the
reinforcing material preferably comprises a
thermoplastic film, a thermoplastic fabric or a
thermoplastic film/paper composite.
Another expandable folder has an integral
front panel member, bottom gusset and rear panel
member and is formed from a single blank of material.
Thus, separate side gussets are provided for
2~7~359
-- 8 --
attachment to the front and rear panel members to form
the folder. The single blank of material and the side
gussets may each be formed of paper, a thermoplastic
film, a thermoplastic fabric or a thermoplastic film
or fabric/paper composite. If desired, the side
gussets may include bottom tab members and a bottom
portion for attachment to the bottom gusset, and the
reinforcing means may extend from the front panel
member across the bottom gusset to the rear panel
member.
Yet another expandable folder in accordance
with the invention is formed from components which
have terminal end portions for attachment to one of
the panel members or the side gusset members to
strengthen and increase the connection of each side
gusset to the panel members as well as the durability
of the folder. Again, the front panel member, gusset,
rear panel member and terminal portions may be
integral and formed from a single blank of material.
These terminal portions can extend from side gussets
and be connected to the panel members, or can extend
from a panel member and across an adjacent side gusset
for attachment to the other panel member.
Advantageously, four terminal portions are present,
two of which extend from the side gussets and are
connected to the panel members, and two of which
extend from a panel member and across an adjacent
side gusset for attachment to the other panel member.
A preferred expandable folder includes
reinforcing means in the form of a sheet of
reinforcing material which substantially covers the
entire outer surface of each panel member to enhance
the tear resistance of the connection of the gusset
member to the panel members. Additional panel members
are secured to each reinforcing means on the outer
surfaces of the panel members to retain the gusset
attachment therebetween.
9 2~7~3~9
Advantageously, the front panel member and
additional panel members are made of red wallet
material, the rear panel member is made of manilla
paper, the gusset is made of plastic film reinforced
paper, the reinforcing means comprises a thermoplastic
film or a thermoplastic film/paper compo~ite, and the
rear panel member has a height which is greater than
the front panel member for viewing the top portion
thereof for purposes of viewing filing indicia which
may be placed thereupon.
Finally, a coating may also be applied on to
the second surfaces of the front and rear panel
members to improve the resistance of the folder to
penetration by liquids and to prevent disfigurement of
the folder due to repeated labeling and relabeling.
The coating and reinforcing means may be
applied alone or in combination to impart the desired
improvements to the folder. The optimum design
includes the combination of all the reinforcing means
and the coating.
BRIEF DE~CRIPTION OF THE DRAWING8
The foregoing and other features of the
present invention will be more readily apparent from
the following detailed description and drawings of an
illustrative embodiment of the invention in which:
Fig. 1 is a perspective view of the
expandable folder of the present invention.
Fig. 2 is a perspective detail view of a
bottom corner of the expandable folder of the present
invention.
Fig. 3 is a longitudinal section of the
gusset of the expandable folder taken along line III-
III of Fig. 1.
Fig. ~ is a transverse cross section of the
gusset taken along line IV-IV of Fig. 1.
Fig. 5 is a plan view of an unfolded gusset.
- lo- 2~7~3~9
Fig. 6 is a longitudinal section of the
gusset taken along line VI-VI of Fig. 5.
Fig. 7 is a schematic drawing of the
flexographic printing process.
Fig. 8 is an enlarged detail view of the
anilox metering roll used in the flexographic printing
distribution system.
Fig. 9 is an additional schematic drawing of
the flexographic printing process.
FIG. 10 is a perspective view of an
expandable folder having a band of reinforcing
material which extends completely around the folder;
FIG. 11 is a perspective view of an
expandable folder having reinforcing s~rips which are
positioned across the gusset at each side of the
folder;
FIG. 12 is a perspective view of an
expandable folder having reinforcing strips positioned
diagonally over the top edge of the gusset where
attached to the front and rear panel members;
FIG. 13 is a perspective view of an
e~pandable folder having a cover and reinforcing
strips which are positioned at the top of the gusset
and the corners of the folder;
FIGS. 14-19 illustrate various gusset top
reinforcements for use in the expandable folders of
the invention, with FIG. 14 providing a perspective
view of the top portion of a gusset and FIGS. 15-ls
representing cross-sectional views of various
reinforcement arrangements taken along line A--A of
FIG. 14;
FIG. 20 is a front view of an integral front
panel, bottom gusset and rear panel blank in a flat
position prior to creasing the gusset folds and panel
member-gusset fold lines;
763~
FIG. 21 illustrates a side gusset for
joining the front and rear panels of the blank of FIG.
20;
FIG. 22 is a perspective view of the
inteyral blank of FIG. 20 which is provided with two
side gussets of FIG. 21;
FIG. 23 illustrates the use of front and
rear panel reinforcemenk in a five-piece expandable
folder which optionally includes gusset top and gusset
corner reinforcement;
FIG. 24 is a front view of a three piece
expandable folder which is made from a blank having
less than full outer reinforcement;
FIG. 25 is a cross-sectional view of the
front panel member of the folder of FIG. 24 taken
along line 25--25 thereof;
FIG. 26 is a front view of an integral front
panel, bottom gusset, side gussets and rear panel
blank in a flat position prior to creasing the gusset
folds and panel member-gusset fold lines;
FIG. 27 is a perspective view of a folder
assembled from the blank of FIG 26;
FIG. 28 is a front view of a portion of a
blank which is similar to that of FIG. 26, except that
the four corners of the blank are cut away; and
FIG. 29 is a perspective view of a folder
assembled from the blank of FIG 28.
DETAII.ED DESCRIPTION OF THE PREFE:RRED EMBODIMENT~
A more complete understanding of certain
features of the present invention can be found in U.S.
Patenk 5,066,045, the disclosure of which is expressly
incorporated herein by reference thereto for the
purpose of further describing and defining such
features.
The term "expandable folder" is used herein
to mean and include expandable pockets, wallets, files
` - 12 - 2~7~3~
and jackets, with or without covers or partitions
which are separate or attached to one of the panel
members.
Referring to the drawings and particularly
ko Figs. 1 and 2, there is illustrated al first
embodiment o~ an expandable folder 10 in accordance
with the present invention. Folder 10 c:omprises a
front panel member 11, a rear panel member 12, an open
top 13 and connection means between front panel
member 11 and rear panel member 12 in the form of a z-
folded expandable gusset 14. Gusset 14 forms a
portion of the sides 15 and the entire bottom 16 of
folder lo.
Front panel member 11 comprises an inner
layer lla and an outer layer llb which are cut or
stamped from a web 35 of heavy paper or cardboard such
as red wallet, red rope, or manila. Inner layer lla
and outer layer llb are glued, stamped or otherwise
attached to each other to form front panel member 11.
Likewise, rear panel member 12 comprises an inner
layer 12a and an outer layer 12b which are cut or
stamped from a web 35 of heavy paper or cardboard such
as red wallet, red rope or manila. Inner layer 12a
and outer layer 12b are also attached to each other by
gluing, stamping, or the like to form rear panel
m~mber 12. In addition, the material of the panels
can be folded upon itself and adhered together to form
both the outer and inner panel members. A typical
arrangement combines manilla paper for the inner layer
12a of the rear panel member 12 and red wallet for the
other three members, but any combination can be made
depending upon the anticipated usage of the folder 10.
However, before outer layers llb, 12b are
stamped from web 35, web 35 is preferably treated on
one side with a liquid resistant acrylic coating 27.
The treated side of web 35 will form the outer surface
of outer layers llb, 12b, and coating 27 will act to
- 13 - 2~7~3~9
prevent moisture permeation into folder 10. Further,
coating 27 will allow for easy labeling and relabeling
of folder 10 by preventing the adhesive on the labels
from actually contacting the surface of folder 10,
thereby preventing disfigurement of folder 10 due to
repeated labeling and relabeling. Preferably, coating
27 will be a styrenated acrylic water based emulsion
36, purchased from Roymal, Inc. of NPwport, New
Hampshire, which is applied by a flexographic press
procedure, as discussed herein.
As shown in Figs. 3, 4, 5 and 6, gusset 14
comprises a sheet of laminated, flat paper 19 that is
repeatedly folded on top of itself in a well known
manner to give it an accordion-like expanding
capability that permits the folder 10 to gradually
expand as it is filled with items to be stored. The
paper forming gusset 14 is of sufficient length to
extend around the sides 15 and bottom 16 of the folder
10, and the width of the paper is selected in
accordance with the desired expanded thickness of the
folder. Gusset 14 ends in terminal folds 17, 18 which
are approximately the same size as the gusset folds.
Alternatively, these terminal folds 17, 1~ may be at
least twice as wide as inner folds 28 of gusset 14, or
at least 7/8 of an inch wide, whichever is greater.
It is preferred to use the extended width terminal
folds 17, 18 to increase the surface area over which
the gusset 14 contacts the panel members 11, 12, thus
strengthening the bond therebetween. However, gussets
having side portions 15 with terminal folds of double
width in combination with bottom portions 16 with
terminal folds of standard width, i.e., as wide as the
inner folds, could also be used for certain folders,
since the stress on the terminal folds of the bottom
portion 16 o~ the gusset 14 is not as great as the
stress on the terminal folds oE the side portions 15.
Of course, the greatest strength joint of the gusset
- 14 -
3 ~ ~
to the panels is when all of the terminal folds are of
double width.
The extended or double width gusset terminal
folds 17, 18 can be achieved by unfolding the last
gusset fold on each end of the gusset so as to provide
the required width prior to attachment t:o the front
and rear panels 11, 12. Alternative]y, the extended
width can be provided by allowing the unfolded end
portions to be of the appropriat~ dimensions. The
latter arrangement is preferred when plastic or
polymer reinforcement is provided on the gusset,
because folded plastic material has a memory which
encourages the material to retain its folded shape,
thus causing difficulty during the subsequent assembly
and manufacture of the gusset onto the panels.
These terminal folds 17, 18 of the gusset 14
may be attachPd to the front and rear panels 11, 12 in
a number of configurations. If desired, the end
portions may be attached to the outer or inner
surfaces of the panels, provided that the entire
surface area of the end portion is attached to the
panel. Since a typical panel includes inner and outer
members, it is preferred from an aesthetic viewpoint
to attach the end portions between the panel members.
To do this, the end portions are positioned between
the inner and outer layers of the front and rear
panels 11, 12 prior to attachment of the members, such
that when the members are attached in the manner
described above, the terminal folds 17, 18 of the
gusset 14 are joined to the front and rear panels 11,
12. In addition, the end portions of the gusset }4
may be provided with a suitable adhesive to increase
the strength of their connection to the panels.
Before flat paper 19 is folded into gusset
14, a reinforcing material, preferably Tyvek~ (DuPont
registered trademark for spun bonded olefin~ or some
other water resistant and durable material, may ba
- 15 - 2~76~5~
affixed to flat paper 19. This reinforcing material
will provide enhanced strength and resistance to
tearing to folder 10, as compared to expandable
folders available in the prior art.
A first location for gusset reinforcing
material is along the entire length and width on one
side of the flat paper 19~ This reinforcement will be
identified as a reinforcement layer 20. Although
reinforcement layer 20 is preferably attached to only
the side of flat paper l9 that will become the outer
surface of gusset 14, a similar reinforcement layer 20
may also be attached to the other side of the flat
paper 19 so that both sides are rein*orced.
Reinforcement layer 20 will prevent the re-shaping of
folds 28 through repeated expansions and contractions
of folder 10 and will protect gusset 14 from liquids.
A second location for reinforcing material
is upon a portion of th~ reinforcement layer 20 at the
~ocations where corners 23 will subsequently be formed
in folder 10. Corners 23 are formed when flat paper
19 is folded to form gusset 14 and gusset 14, in turn,
is attached to the periphery of both the front panel
member 11 and rear panel member 12. This
reinforcement will be referred to as corner strips 21.
Preferably, these corner strips 21 extend along the
entire width of reinforcement layer 20, as shown in
Figure 4. Corner strips 21, in conjunction with
reinforcement layer 20, reinforce and provide
exceptional wear resistance to corners 23, as
discussed hereinbelow.
A third location for reinforciny material is
over the common edge 25 of flat paper 19 and
reinforcement layer 20. This reinforcement will be
referred to and as edge strip 24. Edge strip 24 is
affixed along the entire width of the upper portion of
flat paper 19, over common edge 25, and along the
entire width of the upper portion of reinforcement
2~7~3~
layer 20 (see Figs. 3, 4 and 6). Edge strip 24, in
conjunction with coating layer 20, will protect the
upper portion of gusset 14 from dirt and moisture and
will provide additional resistance tear to gusset 14.
As noted above, the most pre~erred
reinforcemant material is a Tyvek~ thermoplastic film
which includes an adhesive to attach it to panel
members 11, 12 or gusset 14. It is possible, however,
to use other thermoplastic ~ilms or tape to achieve
similar results. Also, paper strips, which are glued
or otherwise attached to the area to be reinforced,
may be used. If so, it is preferred to use a paper
material which is treated by a polymer coating or is
laminated to a plastic material in order to be
resistant to moisture penetration.
Gusset 14 is preferably attached to front
panel member 11 and rear panel member 12 by gluing,
stamping, or otherwise attaching terminal fold 17 in
between inner layer lla and outer layer llb while
layers lla, llb are attached to each other, and by
gluing, stamping, or otherwise attaching terminal fold
18 in between inner layer 12a and outer layer 12b
while layers 12a, 12b are attached to each other.
Thus, inner layers lla, 12a extend to substantially
the out.ermost ends 17a, 18a of the firs~ and last
gusset folds, respectively. It is also contemplated
that terminal folds 17, 18 may be attached solely to
the interior surfaces of inner layers lla, 12a,
resp~ctively, or to the exterior surfaces of outer
layers llb, 12b, respectively. With either method of
attachment, terminal fold 17 will be positioned along
vertical edges llc and bottom edge lld of front panel
member 11, and terminal fold 18 will be position along
vertical edges 12c and bottom edge 12d of rear panel
member 12.
As discussed above, terminal folds 17, 18
preferably have an extended width which is at least
- 17 - 2~7~
twice the width of interior folds 28 or at least about
7/8 of an inch, whichever is greater. Thus, the
surface area over which gusset 14 is att~ched to front
panel member 11 and rear panel member 12 is very
large, as compared with attachment surface areas of
prior art folders, and the bond between terminal folds
17, 18 and front panel member 11 and rear panel member
12, respectively, is exceptionally strong.
Accordingly, if folder 10 were pulled by gusset 14 in
a direction parallel to front panel member 11 or rear
panel member 12, gusset 14 would not separate or tear
away from front panel member 11 or rear panel member
12 as would the gussets of prior art folders.
After folder lO has been assembled,
additional reinforcement is applied to provide even
greater strength and tear resistance to folder 10, as
compared to prior art expandable folders. This
reinforcement is in the form of int rior reinforcing
strips 26 which are affixed to the exposed surface of
inner layer lla from bottom edge lld to top edge lle
along vertical edges llc. Likewise, interior
reinforcing strips 22 are added to the exposed surface
of inner layer 12a from bottom edge l~d to top edge
12e along vertical edges 12c. Interior reinforcing
strips 26, 22 insure that when folder 10 is stretched
after gussets 14 are already fully expanded, i.e. when
folder lO is hyper-expanded, inner layers lla, 12a
have greater resistance to separation from gusset 14.
Additionally, exterior reinforcing strips 2
are added to the exposed surface of outer layer llb
from bottom edge lld to top edge lle along vertical
edges llc. Likewise, exterior reinforcing strips 30
are added to the exposed surface of outer layer 12b
from bottom edge 12d to top edge 12e along vertical
edge 12c. Exterior reinforcing strips 29, 30, may
provide even greater structural stability and
durability to folder 10.
- 18 - 2~7~3~
As discussed above, coating 27 is applied to
web 35 before outer layers llb, 12b of panel members
11, 12, respectively, are formed therefrom by a
flexographic printing procedure. Flexographic
printing is a well-known form of rotary printing in
which aniline inks or layers of other chemicals are
applied to various surfaces by means of rubber or
other elastomeric plates. Flexographic printing is
particularly well suited for applying coating layers
27 on relatively coarse surfaces.
The f lexographic printing process used in
the present invention is preferably repeated twice to
form coating 27. Thus, layer 27 will preferably
comprise an inner layer 27a and an outer layer 27b.
As shown in Fig. 7, the flexographic printing process
typically employs a fountain 40; a reverse-angle
doctor blade assembly 31 attached to fountain 40; an
anilox metering roll 32 in operative relation with
fountain 40 and doctor blade 31; a plate cylinder 33
in operative relation with anilox metering roll 32;
and an impression cylinder 34 which presses web 35
between impression cylinder 34 and plate cylinder 33.
As discussed above, coating 27 will be a
styrenated acrylic water based emulsion 36. However,
because emulsion 36 typically has a viscosity greater
than 3 minutes through a No. 2 Zahn cup, it is
desirable to reduce this viscosity before forming
inner layer 27a and outer layer 27b. Thus, on the
first pass of web 35 through the flexographic printing
process to form inner layer 27a, fountain 40 will be
filled with a fluid 36a which comprises water and
emulsion 36. ~luid 36a has a viscosity between 55 to
60 seconds through the same No. 2 Zahn cup.
Similarly, on the second pass of web 35 to form outer
layer 27b, ~ountain 40 will be filled with a fluid 36b
which comprises water and emulsion 36. Fluid 36b has
a viscosity o~ 25 seconds through the same Zahn cup.
2~76~59
-- 19 --
As shown in Fig. 8, small indentations or
cells 38 are engraved into the entire surface of a
flexible rubber plate 39 by means of well-known
plastic molding techniques. The average number of
cells 38 per square inch of surface area is typically
about lOO,Ooo, but, depending on the application
intended, the number of cells 38 may vary from 30,000
to 300,000. Rubber plate 39 is then affixed to the
circumference of anilox metering roll 32 with the
opening of cells 38 extending radially outward.
The flexographic system operates by rotating
anilox metering roll 32 against fluid 36a in fountain
40, thereby filling cells 38 on the surface of anilox
roll 32 with fluid 36a. As anilox roli 32 rotates,
doctor blade 31 shaves excess fluid 36a off the
surface of anilox roll 32. Anilox roll 32, which
rotates in contact with plate cylinder 33, then
transfers the contents of cells 38 to the surface of
plate cylinder 33 to form a layer of fluid 37a
thereon. Since the size of cells 38 are accurately
controlled, the density of fluid 37a on plate cylinder
33 is relatively uniform to within a variation of
about 2% or less.
Plate cylinder 33 continues to rotate,
thereby transferring the uniform layer of fluid 37a to
web 35. The complementary rotation of impression
cylinder 34, which squeezes web 35 between plate
cylinder 33 and impression cylinder 34, secures the
layer of fluid 37a to web 35 to form inner layer 27a
on web 35.
As shown in Fig. 9, the flexographic
printing process described above is then repeated with
fluid 36b in fountain 40 to form layer ~7b on top of
inner layer 27a, thereby forming coating 27 on web 35.
Web 35 will then pass to a cutting or stamping station
where web 35 will be formed into outer layers llb,
12b. Thus, coating layer 27, which will be on the
- 20 - 2~7~35~
outer surfaces of folder 10, will prevent liquids from
penetrating into folder 10 and will prevent
disfigurement of folder 10 due to repeated labeling
and relabeling
Fig. 10 illustrates an expandable folder 110
of the same basic construction and matexials as folder
10 in Fig. 1. Folder 110 comprises a front panel 112
and a rear panel 114 connected by an expandable gusset
116 which forms the bottom and the sides 118 of the
folder 110. The front panel 112 comprises an inner
member 120 and an outer member 112. Similarly, the
rear panel 114 comprises an inner membrane 124 and an
outer m~mber 126. The folder is open along the top to
facilitate insertion of papers, documents, and other
items which are to be stored in the folder.
To reinforce the joint between the top of
the gusset and the panels, a band of reinforcing
material 134 is applied to the outer surfaces of the
front panel 112, the side portions ll~ of the gusset
116, and the rear panel 114, thus surroundin~ the
entire folder 110. The reinforcing band 134 is
positioned adjacent the top edges of the sides of the
folder 110 and over the end portions 130 of the
gussets attached thereto. The band 134 preferably has
a width of about one inch, although other dimensions
can be utilized.
The band 134 is preferably formed of a
plastic material, such as TYVEK~ thermoplastic
material which includes an adhesive thereon for
attachment of the band to the panel members 112, 114
and side portions 118 of the gusset 116.
Alternatively, if the TYVEK~ material is not adhesive-
backed, the reinforcing band could be aXfixed to the
folder 110 using a suitable glue or other adhesive.
This TYVEK~ material is generally formed as a tape or
fabric which is commonly laminated onto a substrate
such as paper. In addition, other thermoplastic films
2~7~3~9
- 21 -
or tapes could also be used to form the band 134.
These films or tapes could also be adhesive-backed or
affixed to the folder 110 with a suitable adheslve or
glue that is applied either to the band 134 or to the
folder 110. Fiberglass or other filament containing
tape could also be used as the reinforcing material.
Furthermore, a plastic film/paper laminate of
composite, with or without an adhesive kacking, can be
used to form a band having even further increased
strength.
As discussed above, the expandable folder
110 is typically filled to capacity or over-filled
with documents and items to be stored. Often, the
filled folders are stretched or expanded beyond their
limits as documents are retrieved and then returned to
the folder, putting stress on certain locations of the
folder 110, such as where the gusset 11~ is attached
to the panels 112, 114, and often causing tearing at
this connection. Further, when the folders are
retrieved from filing drawers or shelving units, the
folder 110 is often pulled by one of the panels,
frequently resulting in separation of the gusset 116
from the panels 112, 114. Tearing can also result
when a full folder is dropped. The presence of the
reinforcing band 134 at the intersections between the
gusset 116 and panel members 112, 114 strengthens the
folder 110 and prevents separation of the gusset from
the panel members when these types of pulling or
expansion forces are applied to the folder. Thus, the
present invention provides an expandable folder having
increased strength and durability which will increase
the life of the folder.
In another embodiment of the invention, the
band of reinforcing material may be applied to the
inner surfaces of the folder 110 either alone or in
combination with the outer reinforcing band 134. The
inner band is preferably the same width as the outer
2~7~3~
- 22 -
band described above and is preferably positioned
ad~acent the top edges of the side portions 118 of the
gusset 116, across the inner layers 120, 124 of the
panels 112, 114, respectively, and over the end
portions ~30 of the gusset 116 attached thereto~ In
this manner, the inner band reinforces the
intersections of the side portions of the gusset 116
and panels 112, 114 at locations where pulling and
expansion forces ar most often applied to the folder,
thus providing additional strength and durability at
these locations.
The inner reinforcing band is also
preferably formed of a strip of TYVEK~ material which
has an adhesive backing and is applied to the front
panel 112, rear panel 114, and side portions of the
gusset 116. As discussed above, other suitable
reinforcing materials with or without adhesive backing
may also be used as this band.
FIG. 11 illustrates another embodiment of a
reinforced expandable folder 140 wherein like parts
have been numbered correspondingly. In this folder
140, two separate reinforcing bands 142 are provided
to strengthen the locations where the gusset 116 is
attached to the front and rear panels 112, 114 of the
folder. Each band 142 is made of the same material
and has the same width as the other bands discussed
above, but these bands 142 are applied only across a
portion of the outer layer 126 of the rear panel 114,
the side portion 118 of the gusset 116, and a portion
of the outer layer 122 of the front panel 112. The
reinforcing strips 142 are positioned on the outer
surfaces 122, 126 of the front and rear panel 112,
114, respectively, to extend beyond the width of the
terminal ends 130 of the gussets 116 which are
attached therato. In this manner, the reinforcing
bands 142 provide addi~ional strength and support when
pulling and expanding forces are applied to the
- 23 - 2~7~
gussets 116 at its intersection with the panel members
112, 114. Thus, the bands 142 prevent tearing and
separation of the gusset 116 from the panel members
112, 114 and increase the durability and longevity of
the folder.
If desired, the ends of these bands 142 can
be placed between the panel members for aesthetic
purposes. In this embodiment, the gusset would be
attached only to the inner panel members prior to
attachment of the bands 142 and the outer panel
members. Alternatively, these bands 142 can be
attached to the outer panel members prior to the
attachment of the gusset thereto, followed by the
attachment of the inner panels to the outer panels. A
third aspect contemplates the attachment of the bands
142 to the inner panel members after the gusset and
panels are attached together. In this arrangement,
the bands 142 would extend to the top of the gusset to
provide resistance against tearing at that location.
Yet another embodiment of an expandable
folder 150 is illustrated in FIG. 12 where again like
parts have been numbered correspondingly. The top
corners 152 of expandable folder 150 where the top
edge of the gusset 116 is connected to the panel
members 112, 114 has been found to be a highly
stressed location which is prone to failure by
tearing. Thus, folder 150 includes reinforcing
;naterial applied to these top corners 152 to increase
the tearing resistance at these locations. The
reinforcing material is applied in four bands or
strips preferably about one to two inches in width
which are placed over the corner junctions 152 at an
angle of about 45 degrees. Placing these bands at an
angle provides additional resistance against vertical
separation forces, as well as similar resistance to
horizontal forces, compared to the horizontally
applied bands of FIGS. 10-11.
- 24 - 2~7~5~
Preferably, a first pair of bands 154
extends over the top corners of the side portions 118
of the gusset 116 adjacent the front panel 112. Each
band 154 is applied to the outer surface 122 of the
front panel 112 and extends diagonally over the corner
intersection 152 of the gusset 116 for attachment to
the inner surface 120 of the panel. Similarly, a
second pair of bands 156 extends over the top corners
152 adjacent the rear panel 11~, wherein each band is
applied to the outer surface 126 of the rear panel 114
~nd extends diagonally over the top corners 152 for
attachment to the inner surface 124 of the rear panel.
These bands can be placed at any desired angle between
30 and 60 degrees.
The bands 154, 156 are applied to both the
inner and outer surfaces of the panels 112, 114 such
that the reinforcing material extends beyond the width
of the terminal ends 130 of the gusset 116 connected
thereto. The extension of the reinforcing material
past this location provides additional reinforcement
and strength when pulling and expansion forces are
applied to the gusset 116, advantageously increasing
the durability and longevity of the expandable folder
150 .
When inner and outer panel members are
utilized, bands lS4, 156 can be applied after the
gusset is attached to the outer surface of the inner
panel members and prior to attachment of the outer
panel members thereto. Thus, after connection of the
outer panel members, bands 154, 156 would be visible
only on the inside of the folder. If desired, these
visible portions of bands 154, 156 can be covered with
inner strips.
Alternatively, these bands 154, 156 can be
attached to the outer panel members after the gusset
is attached to the inside surfaces of the outer panel
members. Next, the inner panel members are attached
- 25 - 207~9
to the outer panel members to cover the yusset and
bands. In this arrangement, the bands 154, 156 would
be visible only on the outside of the folder. If
desired, these visible portions of bands 154, 156 can
be covered by the cover strips described above or by
additional panel members which are secured to the
outer panel members.
As in previous embodiments desc:ribed herein,
the reinforcing material preferably comprises TYVEK~
material, although other suitable reinforcing
materials may be used. Again, the reinforcing
material may be adhesive-backed or may be attached to
the folder with a glue or adhesive which is applied to
the bands or the folder. The most preferred material
for this band is a TYVEK0 material reinforcéd paper
that includes an adhesive backing.
All embodiments of the invention of FIGS.
10-12 may further include additional reinforcement at
the bottom corners and on the panels at the outer and
inner sides thereof.
FIG. 13 illustrates another folder 160 where
again like parts have been numbered correspondingly.
This folder includes such corner reinforcement 162 for
providing additional wear and abrasion resistance to
those areas of the folder. Also, the top portion of
the rear panel 114 is configured to be a cover which
can be used to protect the paper receiving cavity of
the folder. This cover preferably has a plurality of
score lines therein to conform to various expanded
sizes of the folder. Also, the cover may include tie
members, elastic bands or other means for securing it
in a closed position on the file. If desired, this or
other folders according to the present invention can
also be designed to include or accommodate internal
partitions or separators.
To prevent tearing of the top of the gusset
and to reinforce the joint made between the sides of
2~7~3~
- 26 -
the gusset to the panels near the top of the gusset,
various types of reinPorcement can be applied to the
top of the gusset, as shown in FIGS. 14-lg.
FIG. 14 shows gusset 116 before end portions
130 are attached to the panels. ~einforcement 170 is
provided at the top of the gusset 116 to provide
resistance to tearing or detachment from the panels.
In one embodiment, the top portion of the gusse~ is
folded over itself and secured with glue or an
adhesive to provide the reinforcement 170. It is
immaterial as to whi~h direction the top portion is
folded, i.e., inside or outside as shown. When the
gusset is made of a single sheet of material, such as
paper, the top of the gusset will then have a double
layer of material which is held together by the glue
and which provides increased resistance to tearing.
The inner surfaces of the end portions 130 are also
provided with glue or an adhesive backing o~ one or
both sides for attachment to the panels. The
reinforced gusset can be attached to the inside or
outside~of the panels. When inner and outer panels
are used, the reinforced gusset can be attached to any
surface of either panel member, although, as noted
above, attachment of the gusset between the panels is
commonly used.
Instead of folding the top of gus~et 116
upon itself, a strip of reinforcement can be applied
to one side of the gusset 116 at the top thereof.
Such reinforcement may be made of a wide variety of
materials, including paper, cardboard, a plastic film
of polyethylene, polypropylene, TYVEK~ material, or
the like. The plastic film may contain natural,
synthetic of glass fibers or strands therein to
provide further resistance to tearing or wear. The
desired reinforcing material can be applied to the
gusset using a suitable adhesive, which may be placed
either on the reinforcement or on the qusset. Alæo,
2~7~35~
- 27 -
the reinforcing material can include an adhesive
backing to facilitate attachment to the gusset.
Again, a double layer is provided at the top of the
gusset~
For a greater degree of tear resistance, the
reinforcement material can be applied over the top of
the gusset and onto both the inside and outside top
portions thereo~. A cross section of onP side of the
gusset of this embodiment is shown in FIG. 15, with
the use of a paper gusset 172 and TYVEK~ film
reinforcing layer 174 being illustrated. The paper
gusset 172 is provided with two layers of
reinforcement 174. Again, end portion 130 has a
double width compared to the width of the gusset folds
for a more secure attachment to the panel members.
When one panel member 178 is used, end portion 130 is
provided with a glue or suitable adhesive for
attachment thereto. When two panel members-178, 178A
are used, glue 176, 176A is provided on each side of
the gusset end portion 130 for secure attachment to
the panel members 178, 178A.
An alternative attachment arrangement for
the reinforcement 170 to two panel members 178, 178A
is shown in FIG. 16. In this arrangement,
reinforcement 170 is not attached to end portion 130.
Instead, the end portion of reinforcement 170 is
attached to panel member 178A, while end portion 130
of gusset 116 is attached to panel member 178. As
described above with regard to ~IG. 15, glue 176, 176A
or other suitable adhesive is placed upon the end
portions to assist in obtaining a secure bond to the
panel members 178, 178A.
FIGS. 17-19 show another way that the top of
the gusset can be reinforced. In this embodiment, the
gusset is made of a plastic film reinforced paper
construction, and the top of the gusset i5 folded upon
itself and secured together. This arrangement
- 28 -
2~7~359
provides for a laminate 180 having four layers at the
top of the gusset, namely, paper layers :L82, 182A and
TYVEK~ material layers 184, 184A. FIG. :L7 shows the
end portion 130 of the laminate attached to panel
member 186 by the use of adhesive 188.
An alternative attachment arrangement for
this laminate 18~ to two panel members 186, 186A is
shown in FIG. 18. In this arrangement, the end
portion 130 of the gusset member is cut to provide
dual end portions, each having a TYVEK~ material
reinforcement upon paper. This arrangement can also
be achieved by not adhering the folded over portion to
the other portion of the gusset. Thereafter, one end
portion, made of paper 182 and film 184, is attached
to panel member 186, while the other, which is made of
paper 182A and film 184A, is attached to panel member
186A. As described above, glue 188, 188A or other
suitable adhesive is placed upon these end portions to
assist in obtaining a secure bond to the panel members
186, 186A.
FIG. 19 shows another attachment
arrangement, where none of the layers 182, 182A, 184,
184A of the laminate 180 are secured to each other.
This provides a great degree of versatility in
connecting these layers to the panel members. For
example, one preferred arrangement adheres the TYVEK0
materials 184, 184A to the panel members 186, 186A,
respectively. Since the TYVEK~ material has greater
strength than the paper layers, a stronger joint would
be made. Depending upon the design of the folder, the
TYVEK~ material could be applied to either side of the
respective panel members. In addition, the panel
members could also be sandwiched between the TYVEK~
materials and paper layers. Other arrangements can be
devised depending on the desired configuration of the
~older, and all possibilities are contemplated by this
invention.
- 29 - 2~7~9
If even further attachment strength is
desired for the gusset to panel member connections,
additional layers of plastic material can be added to
these gusset top portions. The designer can best
select the appropriate layers of reinforcement for the
folder depending upon the specific end uses
contemplated.
It should be noted that for each of the
attachment arrangements of FIGS. 14-19, the sid~s of
the panel members extend to the first fold line of the
gusset so that the entire surface area of the
appropriate side of the end portion of the gusset is
adhered to the panel member. As noted above, the most
secure attachments, i.e., those connections having the
greatest strength, are achieved when the areas of the
end portions which are adhered or attached to the
panel members are maximized.
Referring now to FIG. 20, there is
illustrated an integral blank 200 which includes a
front panel member 202, bottom gusset 204 and rear
panel member 206 for forming the folder. The back
side of the blank, i.e., the side which forms the
outer surfaces of the folder, is shown in a flat
position prior to creasing the gusset folds 208 and
panel member-gusset fold lines 210. This blank 200
can be made of a single sheet of any flat, flexible
material, of which paper stock of the desired weight
is typical. For expandable folders requiring greater
strength, the blank 200 can be made of a plastic film
of polyethylene, polypropylene, TYVEK~, or the like,
or a plastic coated paper composite or laminate.
A reinforcing layer is provided at least on
the outer surface of the gusset and onto the front and
side panels to protect against frequent handling of
the folder. The minimum amount of reinforcement to be
applied would be a band or strip which covers the
bottom gusset of the folder and the gusset-panel fold
- 30 - 2~7~
lines. This reinforcement, which is shown in FIG. 20
as the area between dotted lines A and B and the sides
212, 214 of the blank 200, strengthens and protects
the folder from abrasion, such as when it is dragged
along a file drawer bottom or a work station surface
while carrying the weight of heavy stored papers or
other file items. This strip can be easily applied by
lamination onto the bl~n~ as the paper passes through
the cutting machine. Alternatively, the strip can be
glued to the paper, or can be applied as a liquid
coating, as described herein.
The integral blank 200 of FIG. 20 has a
multiplicity of horizontal depressions 208 which are
folded or creased to form the bottom gusset. These
gusset folds 208 are used to expand the folder to
receive larger amounts or quantities of paper.
Previous non-reinforced gussets were known to fail at
these fold lines, with the paper tearing aiong the
fold line during extended folding and unfolding. It
was believed that the reinforcement would be
advantageous in holding together the torn sections of
paper as the folder deteriorates when used. However,
it has been unexpectedly found that the application of
reinforcement along the gusset fold lines
substantially increases the useful life of the folder,
because the paper does not break or tear at the fold
line as it can when it is not reinforced as described
herein.
It is advantageous to extend the
reinforcement to the sides of the front and rear panel
members in the areas where the side gussets are to be
attached. These areas, shown in FIG. 20 as the area
between dotted lines C and D and the sides 212, 214 of
the blank 200, can be reinforced by application of
strips of reinforcing material. These strips should
be wider than the gusset ends which are to be attached
to the panel sides.
- 31 - 2~7~3~
A plurality of these strips can be applied
along portions of the sides of the panels as shown, or
a single strip can be applied along each side of the
blank in a direction perpendicular to the bottom
strip. The side strips can be placed adjacent to the
bottom strip, or they can overlap. The order or
placement of the strips is not critical to the
invention. For hand assembly of the folder, the
reinforcing material along the sides and bottom can be
prepared as an integral piece in the shape of an H and
then applied to the blank.
Preferably, this reinforcing layer is
applied as a single sheet or piece of a reinforcing
material. In one embodiment, the sheet would extend
from the front panel at a location above the
attachment location of the side gussets, over the
bottom gusset and onto the rear panel to location
above the attachment location of the side gussets.
This arrangement is similar to the application of the
bottom reinforcement, except that a wider strip of
reinforcement is utilized, i.e., one which extends
between dotted lines C and D and the sides 212, 214 of
the blank 200. This arrangement is advantageous
because the gusset side attachment locations, which
are a stress point of the folder, would also be
reinforced along with the bottom gusset attachment
location.
Alternatively, the sheet of reinforcing
material can extend along and cover the entire
exterior surface of the blank 200 to provide the full
exterior reinforcement. In this construction, the
bottom gusset, the sides of the front and rear panels
where the side gussets are attached, and the top
portions of the panel members where tabs, labels or
other ~iling indicia are usually attached are all
reinforced. The reinforcing layer serves to
strengthen and protect the entire outer surfaces of
- 32 - 2~7~
the folder from wear associated with frequent
handling. In addition, the reinforcing layer provides
resistance to tearing which can occur when full and/or
heavy folders are moved within the file drawer.
The reinforcing material may be made of a
wide variety of materials, including paper, cardbaard,
a plastic film of polyethylene, polypropylene, TYVEK~,
or the like. The plastic film may contain natural,
synthetic of glass fibers or strands therein to
p ovide further resistance to tearing or wear. The
reinforcing material can be simply laminated to the
blank prior to folding the appropriate lines therein.
The desired reinforcing material can also be applied
to the folder using a suitable adhesive, which may be
placed either on the reinforcement or on the folder.
Also, the reinforcing material can include an adhesive
backing to facilitate attachment to the blank.
Instead of a single sheet or film, a plurality of
reinforcing strips of such materials may be utilized
to provide reinforcement in the desired locations.
Again, these strips can be secured to the blank by
lamination or use of glue or an adhesive.
The application of reinforcement by
lamination is easily accomplished by applying the
reinforcing material onto the paper using pressure.
For this embodiment, the reinforcing material and
paper may simply be passed between two rollers which
supply the necessary pressure to adhere the materials
to each other. It is also possible to apply the
reinforcement as a liquid or solution of a polymer or
resin which may be cured after application to the
paper, if necessary. Other polymer or resin coatings
may be used as reinforcement. Moreover, sheets of
plastic reinforcement may be extruded directly onto
the paper.
Furthermore, when polymeric or plastic
materials are used as the reinforcing layer, the
33 - 2~7~9
folder will be resistant to liquids, such as coffee
and water, which may be spilled onto the folder in an
office environment when the folder is removed from the
file drawer. Yet another advantage can be achieved by
using full reinforcement of a clear plast:ic or
polymeric layer on the outermost panel members so that
the panel members can be pigmented or co}ored more
easily and inexpensively than prior fold~rs, because
the reinforcing material protects the pigmented or
colored portions so that less expensive pigments,
colorants, or dyes can be used. In addition, less
expensive methods can be used for applying such
pigments, colorants and dyes. Also, colored
reinforcement can be used to impart the desired color
to the folder.
FIG. 21 shows a side gusset 220 that is used
with the blank 200 of FIG. 20. This gusset is made of
a material which is resistant to tearing or ripping,
such as a plastic film of polyethylene, polypropylene,
TYVEK~, or the like. The plastic film may contain
natural, synthetic of glass fibers or strands therein
to provide further resistance to tearing or wear. In
addition, the gusset can be made of a plastic coated
paper composite or laminate.
The side gusset of FIG. 21 has a
multiplicity of vertical depressions 222 which are
folded or creased to form the gusset folds that are
used to expand the folder to receive larger amounts or
quantities of paper. Previous non-reinforced gussets
were prone to failure at these fold lines, due to the
paper tearing along the fold line during extended
expanding and collapsing. As noted above, the
reinforcement of this gusset Z20 substantially
increases the useful life of the folder, because the
paper does not break or tear at the fold line as it
can when it is not reinforced as described herein.
- 34 - 2~7~
The side gusset of FIG. 21 can also be
utili~ed to reinforce the side gusset of a
conventional folder. This gusset 220 can be attached
to the panel members of any folder after the
conventional gusset is attached. For a ~ive piece
folder construction, the gusset 220 can be attached to
the outer surfaces of the inner panel members after
attachment of the conventional gusset. Other
arrangements can be devised in accordance with the
teachings of the alternative embodiments of the
present invention.
The end portions 230 of the side gusset can
be of standard width, i.e., substantially the same
width as the gusset folds, or of double width as
described above for additional strength when attached
to the panels. For the specific blank of FIG. 20, it
is preferred to have the end portions of the side
gussets attached to the outer sides of the panel
members upon the reinforcement. Two of these side
gussets are utilized for each blank to form the
folder. These end portions 230 can be applied to the
panel members using a suitable adhesive, which may be
placed either on the end portions or the panel
members. Also, the side gusset end portions 230 can
include an adhesive backing to facilitate attachment
to the sides of the panel members. Although it is
preferred to apply the end portions to the outside of
the panel members, they can instead be attached to the
inside of the panel members for certain folder
designs.
In one arrangement, the corners where the
bottom of the side gusset meets the bottom gusset are
not connected, and the folder resulting form this
construction is shown as 240 in FIG. 22. Although
this construction is acceptable for certain expandable
folders, it is preferred to connect these components
at the corner junction as well as to reinforce the
2~763~9
resulting connection. One connection can be made by
simply extending the length of the side gusset,
forming tabs 224 by cutting the end portions of the
side gusset along the lines 226 shown in FIG. 21,
folding the side gusset bottom along the dotted line
228 which extends between the cuts, attaching the tabs
to the panel members and attaching the lower portion
232 of the side gusset which extends between the tabs
to the bottom gusset. As noted above, the tabs 224
and lower portion 23~ of the side gusset 220 can be
attached to the panel members and bottom gusset with
glue or an adhesive, which may be applied to either
component.
Alternatively, the corner reinforcement can
be made by adding a separate piece or strip of
reinforcement material which extends from the side
gusset to the bottom gusset and partially onto the
panel members. This corner reinforcement can be made
of a material which is resistant to tearing or
ripping, such as those described above for use as the
side gusset. Preferably, the corner reinforcement is
made of a plastic coated paper composite or laminate
which and is applied with glue or an adhesive.
The most preferred folder construction 250
for the integral blank embodiment is shown in FIG. 23
wherein like parts to those described in F~GS. 20-22
have been numbered correspondingly. In addition to
the full outer reinforcement of the blank and the use
of side gussets 220 which include tabs 224 for
attachment to the bottom gusset, there are additional
features present to further reinforce the folder and
achieve an optimum service life. The tops of the side
gussets are reinforced with one of the additional
constructions 252 of FIGS. 14-19, while the corners of
the folder are further reinforced with an additional
piece of a plastic coated paper composite 254. To
enhance the external appearance of the folder,
- 36 - 2~7~3~9
additional front and rear panel members 256 are
secured to the outer surfaces of panel members 202,
206 of the blank 200.
Alternatively, the cover strips can be
placed along the sides of the panel members 202, 206
of the blank over the side gusset/panel member
connections rather than utilizing the additional panel
members 256. In this arrangement, the cover strips
can be made of one of the reinforcement materials
described above to impart wear resistance to these
areas of the folder.
A similar folder can be assembled using the
conventional five piece folder construction, i.e.,
front and back panels, each having inner and-outer
panel members and being connected by a gusset. In
this arrangement, the outer surfaces of the inner
front and back panels would include a layer of plastic
reinforcement covering the entire outer surfaces. The
gusset is preferably made of TYVEK~ material laminated
paper. It is most advantageous to utilize red wallet
as the material for the outer panel members, as well
as for the inner front panel member, with the inner
rear panel member being made of manilla. The gusset
end portions are attached to the reinforcement on the
outer surfaces of the inner panel members before
attachment of the outer panel members thereto. As
noted above, additional reinforcement can be applied
to the top of the gusset, the corners of the gusset,
the outer surfaces of the outer panel members or the
inner surfaces of the inner panel members.
An additional preferred expandable folder
260 is shown in FIGS. 24 and 25, wherein like parts to
those described in FIGS. 20-21 have been numbered
correspondingly. The outer sur~ace reinforcement 262
of the blank extends from just above the side gusset
attachment location 264 on one panel member, across
the bottom gusset and onto the other panel member to a
- 37 - 2~7~3~9
location just above where the side gusset is attached.
If desired, additional panel members or cover strips
can be applied to enhance the appearance of the folder
by hiding the side gusset connection 230. Alsol the
outer surface reinforcement 262 of the blank could be
extended to the top of the outer surface of rear panel
member 206 to reinforce the area where labels or other
filing indicia would be applied and to reduce the
likelihood of crushing or bending that top portion of
the rear panel member.
A similar folder can again be assembled
using the conventional five piece folder construction.
In this arrangement, the outer surfaces of the inner
front and back panels would include a layer of plastic
reinforcement covering the lower outer surfaces as
shown in FIG. 24. The gusset is preferably made of
TYVEK~ material laminated paper, with red wallet as
the material of the outer panel members, as well as
for the inner front panel member, and with the inner
rear panel member being made of manilla. The gusset
end portions are attached to the reinforcement on the
outer surfaces of the inner panel members before
attachment of the outer panel members thereto. As
noted above, additional reinforcement can be applied
to the top of the gusset, the corners of the gussetl
the outer surfaces of the outer panel members or the
inner surfaces of the inner panel members.
Although the preferred constructions of
FIGS. 22 25 include the attachment of the side gussets
to the reinforcement on the outer surface of the
blank, it is also possible to make this connection on
the inside surface of the blank. In this arrangement,
reinforcement material is applied to the inside
surface of the blank in the same manner described
above for the outer areas. For this embodiment, the
previously described blank would simply be reversed,
- 38 - 2~7~3~
i.e., the outer surface would become the inner
surface.
The glues and adhesives of the present
invention represent yet another advancement over the
current state of the art. Generally, cold glues or
adhesives are currently utilized to jvin the
components of a standard expandable ~older. Due to
the structural modifications of the components of the
present invention, such conventional glues are also
suitable for use in assembling the present folders.
For even greater improvement in the joints between
components such as the gussets and panel members,
however, hot melt adhesives are preferred. These
adhesives effectively seal one component to the other,
so that the possibility of failure due to the adhesive
joint is essPntially eliminated. In most instances,
the strength of the joint is greater than the strength
of the component.
Another advantageous manner to secure two
plastic films together is with the use of a cohesive
joint. Again, the strength of the joint is equal to
the strength of the plastic material, so that joint
failures rarely, if ever, occur without also tearing
or damaging the panel members.
Furthermore, the materials utili~ed for the
components of the folders are anther novel aspect of
the invention. For example, the panels, gussets and
reinforcement can be made of a synthetic paper such as
DURALON~ (a registered trademark of Arlon, Inc.),
which includes a sheet of polyester between two layers
of conventional paper. The DURALON~ material
possesses a high strength and is resistant to tearing.
Also, these components can be made entirely from
plastic, with the joints made by ultrasonic welding.
This construction provides the highest degree of
moi~ture and wear resistance oP any of the folder
materials mentioned herein. Since the components are
- 39 - 2~7~3~
welded together, the joint is again as strong as the
materials used to make the components. Another
advantage when using these improved adhesive and
joining systems is that the structural reinforcements
described above can be avoided since these features
are built into the component materials. Also, gusset
end extensions or other joint integrity maintainlng
means can be eliminated, since the strength of the
joints with these systems is essentially equal to that
of the materials of the components.
Referring now to FIG. 26, there is
illustrated an integral blank 270 which includes a
front panel member 272, bottom and side gusset 274 and
rear panel member 276 for forming the folder. The
back side of the blank, i.e., the side which forms the
outer surfaces of the folder, is shown in a flat
position prior to creasing the gusset folds 278 and
panel member-gusset fold lines 280. This blank 270
can be made of any of the materials described above
with respect to the blank 200 of FIG. 20. For
expandable folders requiring the greatest strength,
the blank 270 can be made of a plastic such as
polyethylene, polypropylene, TYVEK~, or the like, or a
plastic coated paper composite or laminate.
If paper is used as the material of the
blank, a reinforcing layer is provided at least on the
outer surface of the gusset and onto the front and
side panel members in the same manner described above
with respect to the blank 200 of FIG. 20.
Preferably, the reinforcing layer extends
along and covers the entire exterior surface of the
blank 270 to provide the full exterior reinforcement.
This allows the entire folder to be made of plastic or
of a plastic film coated paper laminate or composite.
With such materials, everl a conventional five piece
folder structure has component connections of
enhanced strength and increased wear and abrasion
- 40 - 2~7~
resistance. When made out of plastic, the components
can be ultrasonically welded to assemble the folder.
The side yussets are formed by cutting the
blank 270 along lines A, B, C, and D up to their point
of intersection with lines 280. After these cuts are
made, the folder is formed by making the folds in the
gusset, bending the front and rear panel members
upwardly by folding line 280, bending the side gussets
upwardly by folding along the lines which extend
between cuts A-C and B-D, respectively, and then by
bending side gusset end portions 282 so that they fold
either behind the panel members as shown, or
alternatively in front of the panel members, along
line 280. These end portions may then be secured to
the panel members by glue or an adhesive, by cohesive
bonding or by ultrasonic welding, depending upon the
material of the blank. FIG. 27 illustrates the final
folder after assembly. If desired, the corners of the
rear panel member can be rounded by cutting.
Another folder configuration can be achieved
by utilizing the same blank 270 of FIG. 26, but with
the side gusset end portions 282 being cut out
differently. In one ~lternative, these end portions
282 can be cut along lines 280 from the sides of the
blank 270 to the junction with lines A, 8, C, and D,
respectively. The folder is then formed by making the
folds in the gusset, bending the front and rear panel
members upwardly by folding line 280, bending the side
gussets upwardly by folding along the lines which
extend between A-C and B-D, respectively, attaching
the side gussets to the panel members by use of an
adhesive or other means, bending the end portions 2~2
along lines A, B, C, and D, respectively, so that they
extend around the outside of the side gussets, and
then by attaching these end portions 282 to the outer
surface panel members by glue or an adhesive, by
`` - 41 - ~7~35~
cohesive bonding or by ultrasonic welding, depending
upon the material of the blank.
In this arrangement, the side gussets are
protected by two end portions, which do not have to be
attached to the side gusset. Advantageously, the end
portions can be provided with folds that correspond to
the folds 278 of the side gusset 274. If desired, an
adhesive can be used to attach the end portions to the
side gusset. Since the height of the panel members is
generally greater than the width of the side gusset,
the end portions will be taller than the side gusset.
To remedy this difference, the corners of the blank
can be cut away so that the heights of both the side
gusset and the end portions will be the same.
Yet another folder configuration can be
achieved by utilizing the same blank 270 of FIG. 26,
but with some of the side gusset end portions 282
being cut out differently. In one of these
alternatives, two end portions 282 can be cut along
lines A and D, while the two remaining end portions
can be cut along lines 280 from the sides of the blank
270 to the junction with lines B and C, respectively.
The folder is then formed by making the folds in the
gusset, bending the front and rear panel members
upwardly by folding line 280, bending the side gussets
upwardly by folding along the lines which extend
between A-C and B-D, respectively, attaching the side
gussets and first end portions to the panel members by
use of an adhesive or other means, bending the
remaining end portions 282 along lines B and C,
respectively, so that they extend around the outside
of the side gussets, and then by attaching the.se
remaining end portions 282 to the outer surface panel
members by glue or an adhesive, by cohesive bonding or
by ultrasonic welding, depending upon the material of
the blank. In this arrangement, each side gusset is
protected by one end portion, while the other end
2~7~3~9
- 42 -
portions are attached to the outer surfaces of the
panel members. As above, the end portions which
protect the side gussets can be in spaced ad~acent
relation or attached to the side gusset. If desired,
two corners of the blank can be cut away so that the
heights of both the side yusset and the protective end
portions will be the same.
FIG. 28 illustrates another embodiment of
the one-piece folder. In this arrangement, the gusset
end portions 286 are reduced in size by cutting a
portion away along line E. While only one corner of
the blank 290 is illustrated in FIG. 28, it is
understood that each corner of the blank would be
treated in the same fashion. The gusset end portions
can be of standard width, i.e., substantially the same
width as the gusset folds, or of double width as
described above for additional strength when attached
to the panel members. If an all plastic construction
is used, these end portions 286 can be attached either
to the outer or inner sides of the panel members.
Where a plastic/paper laminate or composite is used,
the gusset should be attached so that plastic is
joined to plastic ~or optimum joint strength. The
final folder for this embodiment is shown in FIG. 29.
When the folder of FIG. 29 is made from a
relatively inexpensive material such as paper, the
side gusset 220 of FIG. 21 can also be utilized to
reinforce the side gusset 274 of the folder. This
gusset 220 can be attached to the panel members after
the side gusset 274 is attached. As noted above,
other arrangements can be devised in accordance with
the teachings of the alternative embodiments of the
present invention.
For aesthetic purposes, the outer sides of
the panel members of the folders of FIGS. 27 and 29,
as well as the alternative embodiments of those FIGS.,
may be provided with the cover strips described above
_ 43 - 2~7~3~
or by additional panel members which are secured
thereto.
Expandable folders formed according to this
invention provide a number of advantages to the user.
Various types of reinforcement are provided about and,
preferably, over the top of the gusset to prevent
tearing or other failure when the folder is
overstuffed with file materials. In addition, the end
portions of the gussets along the sides and, where
applicable, the bottom, have a width which is at least
twice the width of the gusset folds to provide a more
secure joint with the panel members, which joint is
capable of providing increased resistance to tearing
away or otherwise separating from the panel members.
The outer surfaces of the inner front and rear panel
members are also reinforced to strengthen the folder
at least in the areas where the gusset is attached,
and, for best results, on the entire outer surfaces of
the panels.
If desired, the corners of the gusset may be
reinforced to prevent wearing due to abrasion with
file drawer or work surfaces such as would be caused
by sliding the file bottom across those surfaces. It
is also possible to reinforce or coat the surfaces of
the outer front and rear panel members in critical
areas which are subject to stress, wear or abrasion.
For an optimum construction, substantial~y
all outer surfaces of the folder are provided with
reinforcement to prevent degradation from moisture or
other contaminants. Such outer rein~orcement also
allows less expensive pigmentation or colorants to be
utilized on the paper substrate. The edges of the
inner front and rear panel members can be reinforced
at the areas where the gusset is attached to further
prevent tearing or detachment. All these advantages
add to the durability of the file and prolongs its
useful life.
44 20763~9
The strength and resistance to tearing of
expandable folder 10 according to the present
invention was compared to other expandable folders
available on the market. The following test results
clearly and unequivocally demonstrate the! superior
durability and enhanced strength of the expandable
folder of the present invention.
FRONT AND REAR PANEL MEMBER PULL_ TEST
This first test demonstrates the enhanced
resistance to tearing of gusset 14 from front panel
member 11 or rear panel member 12 when folder 10 is
stretched after gusset 14 is already fully expanded.
In this test, a rectangular metal box with a
hinged top was fit into different types of expandable
folders. The box was as wide as the folders ~hen the
folders were fully expanded and was as long as the
distance between the points of connection of the
gusset with the front and rear panel members. A pull
ring was attached to the top of the box, which
extended out of the folder, opposite the hinge, and a
scale was attached to the pull ring.
A pulling force was then applied to the pull
ring through the scale. ~his pulling force opened the
top of the box and pulled the front panel member and
rear panel member away from the gusset, thereby
simulating hyper-expansion of the folder. The folders
were considered to have failed when the gusset
separated from the front or rear panel member, and the
force required to cause the failure was measured with
the scale.
The results of this test are tabulated
below:
_ 45 - 2~7~359
_
Manufacturer ~ ~ Product~ ~ 5'e~t R~ault~ _
Company A File pocket with~ailed at 9 lbs.
conventional 3~"
¦_ paper gusset
Company A File pocket wi~hFailed at 8 lb~.
conventional 3~"
cloth qus~et
I _ . .
Company A File pork~t wlthFalled at 21 lb~.
newly developsd 3~"
TvvekD ~u~et
I _ . ., _ _
Company B File pocket withFailed at 12 lb~.
conventional 3~"
paper gusset
_ ~ _ . _ . I
Company B File pocket withFailed at lO lb~.
conventional 3~"
Tyvek0 gussot
_ I
Company 8 File pocket withNo ~ilur~ at 50
reinforced 3~" lbs.
gu~et according to
the present
invention
_ I
Company B Expansion walletNo failur~ at 50
with reinforced 3~" lb~.
gus~et according to
the present
invention
_ _
CORNER RUB TEST
The corner rub test demvnstrates the
increased wear resistance of corner 22 of folder 10.
In this test, various expandable folders
were filled with nine pounds of paper. An oscillating
arm rubbed the loaded folder with an abrasive crocus
cloth at a rate of 654 strokes per hour and at a
fifteen degree angle with respect to the bottom of the
folder. The cloth was changed every 2500 cycles. The
folders were considered to have failed when a hole
appeared in the corner.
The results of the test are tabulated below:
- 46 - 2~ 7~3~
. _ _ _ _ _
Manufacturer . ~ Product ~ . ` Test Reault~
_
Company A Conventional Hole developed at
3~" Tyvek~ gus~et 6000 cycle~
Company A Conventional 3~" }lole developed at
cloth gu~set 4000 cycle3
_. .
Company B Conventlonal 3%~ Hole d~veloped at
Tyvek~ gus~et 11000 cycle~
_
Company 8 Reinforced 3~" No hol~ at 17000
gusset according to cy~l~#
the present ~ole developod at
invention ~ 44,000 cycl~s
_ . _ -
DROP TEST
This test demonstrates the enhanced ~oad
bearing capacity and improved loaded performance of
folder 10.
Various folders were filled with ten pounds
of paper and dropped from a height of four feet. The
folders were dropped on the gussets, on the corners,
on the front panel member, and on the rear panel
member. The folders were considered to have faile~
when they split or tore.
The results of the test are tabulated below:
Manufacturer ~ ~ Product~ ~ Te t e~ul g_~
Company 8 Conventional 3~ Failure in each drop
Tyvek3 gusset te~t
_ _ _
Company B Conventional 3~" Failure ln each drop
paper gusset te~t
Company B Reinforced 3%1- No fail~rn aftar 14
gu~et according to total drops (5 on
the present gu~ets, 5 on corner
invention 4 on panel member~)
_
REPEATED MEÇHANICAL OPENINGS
This test demonstrates the enhanced
durability in use of folder 10.
An arm which had two diametrically opposed
cams thereon was supported between two leaf springs.
2~76~9
47 -
Attached to each spring was a plate that was as high
as the front and rear panel member and as long as the
distance between the points of connection of the
gusset with khe front and rear panel member.
This apparatus was placed inside di$ferent
types of expandable folders with the plates flush
against the front and rear panel members. The low
portions of the cam lobes were against the leaf
springs when the expandable folder was in its relaxed
position.
The arm was then rotated at a rate of 9.6
revolutions per minute, thereby causing the cam lobes
to open and close the springs 19.2 times per minute.
The springs, through the plates, thereby fully
expanded and relaxed the expandable folder to simulate
use of the folder. The folders were considered to
have failed when the gussets separated from the front
or rear panel member.
The results of the tests are tabulated
beIow:
. _ - - I
-Manufacturer:~ Product ~ ~ Te~t ~esults
, _ _ . _
comPanY B Conventional 3~" Failed within 24
paper gusset hrs.
Company B ~ Reinforced 3~ No fallur~ aftsr 72
gus~et according to hrs. of continuou~
the present testing
inventi~n
_
GUSSET PULL TEST
This test demonstrates the enhanced
resistance to separation of gusset 14 from the front
or rear panel members 11, 12 when a pulling force is
applied to gusset 14 in a direction parallel to the
front or rear panel member 11, 12.
In this test, various types of expandable
folders were filled to capacity. A clamp was then
attached to the upper edge of the fully expanded
- 48 -
2~3~
gusset, and a pull ring was attached to the clamp
through a scale.
A pulling force which pulled the gusset away
from the panel member was then applied to the gusset
through the pull ring. The folder was considered to
have ~ailed when the gusset tore or was pulled away
from the front or rear panel member. The force
required to cause the failure was measured with the
scale.
~ The results of this test are tabulated
below:
Manufacturer ~ _Product : ~Test Results
Company A with 3~" Failed at 32 lbs. l
g u g g e t I
,
Company A with 3~1' Failed at 40 lb~.
conventional paper
lusset
. _ I
Company B File pocket with Failed at 27 lbs.
conventional 3~"
paper gusset l
~ _ _ I
Company B File pocket wlth Failed at 31 lb~.
conventional 3~"
Tyvek~ gu B aet
_ _
Company B File pocket with ~o failuro with
reinforced 3~" pulling forco#
gusset according to greater than 50 lb~.
the present
invention
Company B with 3~ Failed at 28 lbs.
conventional paper
. . gusset
Company 8 Expan~ion wallet No failure with
with reLnforced 3~" pull~ng forco3 of
gusset accordlng to 50+ lbs.
the present
invention
_ _ . .
GUSSET TEAR TEST
The gusset tear test demonstrated the
increased resistance to tearing of gusset 14.
- 49 - ~763
This test employed a method and apparatus
known as the Elmendorf-type method to measure the
internal tearing resistance of paper. The ElmPndorf
method measures the force perpendicular to a plane of
paper that is required to tear sheets of paper through
a specified distance after a tear has been started. A
complete description of the method and apparatus is
disclosed in TAPP1 T 414 Test Methods, Vol. 1, pages
1-6 (1991), which is incorporated herein by reference.
The results of the test are tabulated below:
r ~ ~ l
~ . Manufa~turer ~ Product ~ T~B~ ~e~ult~ l
~ -- ~ _ I
Company A Conventional 3~" Failed at 700 gram~-
paper guq~et force
Company 8 Conventional 3~" Failed at 750 gr~m~-
¦ paper gus~et for~e
Company B Conventional 3~" Failed at 770 grams-
Tyvek0 gu~set force
¦ Company B ReLnforced 3~ No failur~ at
gu~set accordiny to grPater than 1,OOO
the present gra~s-force
inventio~
. _
Accordingly, the above tests demonstrate the
greatly enhanced durability, strength, and resistance
to tearing of the expandable folder of the present
invention as compared to other expandable folders.
Folder 10 has increased resistance to failure when
gusset 14 is hyper-expanded, when it is picked up by
either front panel member 11 or rear panel member 12,
or when it is dropped. Further, gusset 14 has
increased resistance to separation from front panel
member 11 or rear panel member 12 when gusset 14 is
pulled, and gusset 14 has increased resistance to
tearing. Finally, folder 10 has increased resistance
to penetration of liquids and corners 22 have
increased resistance to wear. Applicants have
designed the expandable folder 10 of the present
2~7635~
- 50 -
invention to include these features 50 that its useful
life will be significantly prolonged.
While the present invention has been
particularly shown and described with re~erence to the
preferrad embodiments thereof, it will be understood
by those skilled in the art that various changes in
form and details may be made thereto. For example,
the gusset can be reinforced with both an outer and
inner reinforcement, or a layer of plastic film can be
applied to the gusset after assembly of the folder as
reinforcement.
It is also contemplated by the present
invention that reinforcements 20, 21, 24, 27, 28, 29,
30 be used with other types of expandable folders,
namely elastic-tie expandable folders, filing jackets,
hanging folders, and wallet-type folders. Further,
individual compartments or pockets may be formed
within folder 10, as disclosed in United States Patent
No. 1,698,841.
According to the provisions of the Patent
Statutes, we have explained the principle, preferred
construction and mode of operation of our invention
and have illustrated and described what we now
consider to represent its best embodiments. However,
it should be understood, that within the scope of the
appended claims, the invention may also be practiced
otherwise than as specifically illustrated and
described.
