Note: Descriptions are shown in the official language in which they were submitted.
7~L~
1 S P E C I F I C A T I O N
This invention relates to the art of reclosable bags,
the material for making such ~ags, and method of and means
for making the same, and is more particularly concerned with
bags of the ~ind provided with extruded resiliently flexible
plastic profiled reclosable separable fastener means.
The art of making reclosable bags e~uipped with
extruded plastic profiled reclosable separable fastener
means has seen a long period of development as reflected in
numerous patent disclosures. It has been conventional
practice to extrude plastic material in tubular or strip
sheet or web form with the profiled separable fastener
means coextruded along and parallel to the longitudinal
formation axis of the web, tha-t is, the direction in which
the web is extruded. On the other hand, prefabricated
separable fastener strip means have been secured to
separately formed web and with the fastener strip means
extending longitudinally parallel to the longitudinal
formation axis of the web.
By way of example, patent Re. 29,043 i9 reEerred to
as disclosing coextrusion of web and fastener means and
forming the same into bag sections.
U.S. Patent 3,948,705 exemplifies the technique of
securing reclosable separable fastener strips to plastic
film parallel to the longitudinal formation axis of the web
by fusion or heat seal methods.
Attachment of separable fastener strips parallel to
the longitudinal formation axis of the web by adhesive
means is exemplified in U.S. Patents 4,372,793; 4,354,541;
and 4,355,494-
8874 [3
1 U.S. Patent 4,Q46,408 discloses separably
interlockable fasteners along the edges of the plastic
sheet material having generally arrow shaped profiles, the
fasteners being either integrally extruded with flat sheets
or tubes of plastic film, or supplied in the form ofextruded strips attached to the web or film by heat sealing.
According to all of those prior patent disclosures,
it is necessary to provide at least a pair of spaced
longitudinally extending complementary profile fastener
strips along the longitudinal extent of the bag material
web or film so that when the material is folded upon itself
along one or more folds parallel to the separable fastener
strips, the fastener profiles will be aligned with one
another in interlockable relation and extend along the top
or bag mouth edges of the bag sections into which the
material is suhdivided by sealing the same at spaced
intervals across the length of the material to provide
closed sides for the bag sections.
Where separate matching strips of the web or film
material carrying the complementary profile fastener strips
longitudinally along the long.itudinal extent of the
material are aligned in face-to-face relation to provide
bag sidewalls, the same requirements must be met as
described for the foldable material for fabricating the
same into bag sections, except that all side and bottom
edges of the bag walls must also be secured together in
those completed bags.
Those prior techniques do not necessarily limit the
length of bags to be produced thereby, that is, the length .
from the bag top end to the bottom end of the bag, unless
the bags are supplied for filling by the type of filling
machines commonly referred to as form, fill and seal
--2-
~ 3740
1 machines, such as exemplilied in U.S. Patent 4,355,~g4.
Where the fastenex strip means are located
longitudinally along the length of the bag making web
material, the length of the bags that can be produced in
the form, fill and seal machines is limited to the diameter
of the filling nozzle about which the film or web material
is progessively wrapped. Further, unless the fastener
profiles are interlocked before the bag forming material is
wrapped about the forming extent of the filling nozzle or
at least before the usual longitudinal sealing of the joined
longitudinal edges or margins of the bag forming material,
there is a considerable problem with attaining inter-
lockable registration of the fastener profiles.
Furthermore, if and when used on vertical form, fill,
and seal apparatus, bag material as shown in U.S. Patent
4,355,494 has certain shortcomings, as the material will
produce finished bags having reclosable fastener means
running in the longitudinal formation direction of the
material and, thus, in a vertical direction along the bags.
Such bags may not be commercially acceptable for some
products, eg., some types of candies, potato chips, and
other snack foods.
By the present invention, the problems, disadvantages
and shortcomings inherent in prior techniques are overcome
especially as related to vertical form, fill and seal
arrangements for making and f lling bags, but also for bag
making generally.
An important object of the present invention is to
provide new and improved bags formed from film or other web
material having thereon extruded reclosable plastic fastener
means extending across the longitudinal formation axis of
the web material.
~L2~
Another object of the invention is to provide
a new and improved method of making bags with
reclosable plastic fastener means.
A further object of the invention is to
provide new and improved material adapted ~or making of
reclosable bags having complementary profile extruded
plastic fastener strips extending across the mouth ends
of the bags.
Pursuant to the present invention there is
provided a reclosable bag having a body with top and
bottom ends and confronting walls, and the bag walls
formed from web material having its longitudinal
formation axis extending between the top and bottom
ends of the bag body, and extruded resiliently flexible
plastic profiled reclosable fastener strip means
secured to the bag walls at the top end of the bag body
and extending lengthwise across the longitudinal
formation axis oE the web material.
There is also provided by the present
invention new and improved material for making a
reclosable bag, comprising a web having a longitudinal
formation axis and adapted for forming into a bag with
the formation axis extending between a top end and a
bottom end of the bag, and extruded plastic profiled
reclosable fastener strip means secured to the web
lenthwise across the formation axis of the web and
adapted to be located across the top end of the bag.
This invention further provides a new and
improved reclosable bag having a body with top and
3~ bottom ends and confronting walls, the walls having
formed from web material having the longitudinal
,z ~
7~
formation axis extending between said top and bottom
ends of the bag body, and the material joined to itself
at a joint extending between said top and bottom ends
and along one side of the body, and continuous one-
piece extruded resiliently flexible plastic profiledreclosable fastener strip means extending across said
joint and secured to both of said walls at one end of
the bag body and extending lengthwise across said
longitudinal formation axis of said web material, said
reclosable fastener strip means being folded upon
itself at said joint and having its profiles aligned
and releasably interlockable with one another in the
folded strip means. ::
ON THE DRAWINGS
Other objects, features and advantages of the
present invention will be readily apparent from the
following description of certain representative
embodiments thereof, taken in conjunction with the
accompanying drawings, although variations and
modifications may be effected without departing from
the spirit and scope of the novel concepts embodied in
the disclosure, and in which:
FIG. 1 is a perspective view of a bag
embodying features of the invention;
FIG. 2 is a longitudinal sectional view taken
substantially along the line II-II in FIG. 1;
FIG. 3 is an enlarged fragmentary vertical
sectional view through the top of the bag of FIG. 1
after it has been opened and the reclosable separable
fastener snapped together;
A
` ~2~38'7~L~
1 FIG. 4 is a schematic illustration of means for
applying preformed extruded plastic profiled reclosable
fastener strip means to bag forming web material;
FIG. 5 is a schematic perspective ~iew of a vertical
bag forming, filling and sealing apparatus;
FIG~ 6 is a transverse sectional elevational view
taken substantially along the line VI-VI in FIG. 4;
FIG. 7 is a schematic sectional elevational view
taken substantially along the line VII-VII in FIG. 6;
FIG. 8 is a transverse sectional plan view taken
substantially along the line VIII-VIII in FIG. 5;
FIG. 9 is a view similar to FIG. 8, but showing a
slight modification;
FIG. 10 is another view similar to FIGS. 8 and 9,
but showing still another slight modification;
FIG. 11 is an enlarged fragmentary perspective view
of the extruded plastic profiled closure fastener strip
~eans as applied to the web and provided with a V-notch to
facilitate folding;
FIG. 12 is a fragmentary sectional perspective view
showing the fastener equipped web of FIG. 11 folded and
the fastener interlock;
FIG. 13 is a schematic illustration of a modified
means for applying the fastener strips across the length of
a web;
FIG. 14 is a top plan view of a web which has been
provided across its formation axis, i.e., its length, with :
separable fastener strip means by the apparatus of FIG. 13;
FIG~ 15 is a fragmentary sectional detail view showing
a reclosable bag top having sealing means associated with
the separable fastener; and
1 FIG. 16 is a si~lilar view showing a modification of
the sealing means and fastener combination.
In FIGS. 1-3 is shown a reclosable bag 20 having a
body with a top end 21 and a bottom end 22 and confronting
walls 23 and 24. The walls 23 and 24 are formed from web
material which may, and for some purposes desirably does,
have its longitudinal formation axis extending between the
top and bottom ends 21 and 22 of the bag body, as indicated
by the double ended dashed arrow 25. Elongated, extruded
resiliently flexible plastic profiled reclosable fastener
strip means 27 secured to the walls 23 and 24 at the top
end 21 of the bag body extends across the longitudinal
formation axis 25 of the bag body web material.
~ny material which will suit the purpose for whicn
the bag 20 is intended may be employed. Thin sheet-form
packaging material such as suitable thermoplastic, and if
desired gas impervious single layer or laminated extruded
film formed from polyethylene, polypropylene, and the like,
may be utilized. Such material is adapted to be formed
into bags on a continuous production line wherein the
material is supplied to bag production apparatus which
may or may not be combined with bag filling and sealing
means. Generally, because extrusion can ~e carried out at
a much greater speed then most bag making and filling
apparatus can utilize the material, the sheet film of
whatever character, hereinafter to be generically referred
to as web, is rolled into suitable supply rolls since the
rolling process can be effected at the same speed as the
extrusion and web curing takes place, and then the supply
rolls are utilized for supplying bag making web to the bag
forming apparatus, which may be combined with means for
filling the bags with contents.
~7~
lExtruded products, and in particular extruded web,
regardless of the material from which the web may be
extruded, including plastic materials such as polyethylene,
polypropylene, and the like, and paper which is generally
produced by extruding a paper making fibrous slurry ~rom a
nozzle generally identified as a "slice" onto a porous
forming belt, have certain telltale characteristicswhich
will identify the formation axis of the web to those skilled
in the art. Such telltales may comprise any one or more
of molecular orientation, extrusion die markings, guide
means markings or slight scra~ches, grain orientation, and
the like, and generally extending along the production or
machine direction length of the formed web and herein
referred to as "the formation axis".
15Bags of the kind exemplified in FIGS. 1-3, are
adapted to be made by supplying the desired web material,
whether single ply or laminated, to a form, fill and seal
machine 28 schematically exemplified in FIG. 5. Such
machines are well known in the art and include a combination
bag forming and filling nozzle cylinder 29 adapted to
receive product to be filled into the formed bags from a
hopper 30. Bag making web 31 carrying the reclosable ~:
fastener or zipper means 27 extending across the formation
axis of the web at suitably longitudinally spaced intervals
along the web, is guided as by means of guide roller 32 to
the cylindrical outer surface of the cylinder 29.
At the cylinder 29, a fol~ing or wrapping arm device
33 guides and wraps the web 31 about the cylinder 2g with
the longitudinal margins of the web brought together into a
longitudina~, laminar closure fin ~ssembly 34. Sealing of
the fin assembly 34 into a closure seam is effected by means
such as a pair of vertical sealing bars 35 which are
74q:~
movable from a spaced clearance relation into clamping and
sealing engagement with the closure fin assembly 34, as
indicated by the solid directional arrows 37. The bars 35
are then separable as indicated by the dashed arrows 38 to
release the heat sealed seam section of the fin assembly 34
of the now closed bag forming tube of the web material.
Advancement of the longitudinally sealed tube by
bag length increments is effected by means of a pair of
horizontal, parallel bag end sealing bars 39 which are reci-
procatingly operable, in a manner similar to the fin sealingbars 35, for clampingly engaging the bag web tube below the
end of the cylindrical forming and filling nozzle member 29
for simultaneously sealing the top end of a filled bag
section 20 and the bottom end of the next succeeding bag
section. Then the sealing bars 39 still gripping the bag web
tube, move downwardly a bag section length as indicated by
the directional arrow 40 to pull and advance the entire bag
making tube one bag increment downwardly. As this occurs,
the next succeediny bag is filled with product dropped down
the cylinder 29 from the hopper 30. As the sealing and pull
down bars 39 reach the lower end of their sealing and pull-
down stroke, severance means such as a cutoff bar 41 cuts
midway across the seal 42 that has been effected by the bars
39, thus releasing the previously filled bag 20 which may
then be handled as desired, such as to be packed for market.
Having completed its downstroke, the sealing bar and cutoff
device 39, 41 returns as indicated by the dashed directional
arrow 43 to its starting position adjacent to the lower end
of the cylinder 2~. It will be understood, of course, that
operation of the vertical sealing bars 35, and the hori-
zontal sealing and pulldown bars 39 are operated in coordinated
_9_
D
~Z~387~L~
1 cyclical relation, as is well known in the art for form,fill and seal machines of this type.
One salient aspect of the present invention resides
in having the reclosable fastener means 27 extend across
the longitudinal formation axis 25 of the web material 31,
and so located that as each of the bags 20 is completed,
the reclosable sealing means 27 will be at one end, which
subsequently may become the top end of the bag body and
inside of the top end seal 42 of the completed bag. Through
this arrangement, the bags formed in the machine 28 may be
of any desired length, within the reciprocal range of the
sealing bars 39. On the other hand, the maximum length that
has been attainable heretofore was limited by the diameter
of the cylinder 29 so that for different bag lengths,
different diameter forming cylinders had to be provided. In
the prior bags the reclosable fastener extended longitudin~
ally parallel to the longitudinal seam ~ormed by the vertical
sealing bars 35, rather than extending parallel to the
horizontal sealing and pull down bars 39 as is effected by
the present invention which attains great versatility as to
the length of bag that may be produced for any given width
of bag made on a particular diameter of forming and filling
cylinder.
In one preferred arrangement, the fastener means 27
may be secured to the web material 31 in an assembling and
securing station upstream adjacent to the ~orm, ~ill and
seal machine 28, as exemplified in FIGS. 4, 6 and 7.
Preformed extruded plastic, profiled reclosable fastener
strip 44 may be fed from a supply roll 45 to and across and
secured to the web 31 which in operation is caused to advance
toward the machine 28 as indicated by the directional arrow
45 in FIGS. 4 and 7. Such advance of the web 31 may be
--10--
37~6~
effected step-by-step by means of driven pinch feed r~lls 47
driven as b~ means of a motor 4~ in coordinated relation :~
with the step-by-step advance of the formed bag tube in the
cyclical operation of the machine 28. Coordinated feed of
the fastener strip 44 to the web 31 may be effected by means
of pinch type feed rolls 49 driven step-by-step as by means
of a motor 50 coordinated with operation of the machine 28
and the motor 48.
Upstream from the fastener guide and feed rolls
49, the fastener strip 44 with its base supported on an
elongated anvil or pressure bar 51 and with interlockable
profiles 52 projecting upwardly, is provided with
longitudinally spaced V-notches 53 by the operation of means
such as notching tools 54. These tools are located at
suitably spaced relation to one another along the length of
the fastener strip 44 dependent upon the width of the bags
to be made from the web 31 after the fastener strip 44 has
been secured to the web.
As best visualized in FIGS. 11 and 12, the pro-
files of the fastener stri.p 44 are preferably of generallyarrow shape in cross section and there are a plurality of
the profil.es, such as three, extending in spaced parallel
relation along the fastener strip 44. The notches 53
extending across the profiles are aligned with fold lines 55
at what will be the closed joint sides of one of the
completed bags 20. The notches 53 facilitate bending or
creasing of the base of the fastener strip for interlocking
of the fastener profiles 52 by folding over the assembly
onto itself as indicated in FIG. 12. Further, the notches 53
facilitate interlocking of the profiles 52 when they are
brought into bag closing relation and effect relative
lateral adjustment to one another from the axial alignment
--11--
%~87~0
1 in which they were formed in the fastener strip. Such
lateral adjustment which is minor, but necessary to permit
the profiles to interlock on the folded strip, is indicated
by the directional arrows 57 in ~IG. 12. By having a
plurality of the parallel fastener profiles 52, inter-
engagement of the profiles of the folded section is
facilitated since critical lateral alignment is not
necessary.
In the finished fully sealed bag the profiles 52 may
remain separated as shown in FIG. 2 until the top end or
mouth of the bag has been opened as shown in FIG. 3 for
access to contents in the bag, and then the bag can be
closed by interengagement of the fastener profiles as shown
in FIG. 3. Opening of the bag may be effected either by
pulling the seal 42 at the top end of the bag open, or by
severing the top end of the bag along a line 58 between the
seal 42 and the reclosable fastener 27 and then using the
sidewall portions 59 located outwardly from the fastener 27
as pull flanges for pulling the closed fastener open when
desired. Simple digital pressure applied to the folded over
portions of the strip 44 of the fastener 27 effects inter-
locking of the profiles 52.
Returning to FIGS. 4, 6 and 7, sectional lengths of
the fastener strip 44 which may be equal to the width of
the web 31 are adapted to be guided into position across
D the web by ~e~ comprising a vacuum head 60 carried by a
reciprocatable traverse bar 61 by which the vacuum head 60
is caused to extend across the width of the web 31 to bring
the ~acuum head 60 into position downstream adjacent to the
feed rolls 49. These rolls are sufficiently spaced from the
adjacent edge of the web 31 to pro~ide for a terminal portion
of the fastener strip 44 to be in position in each strip
~12-
~ ^ ~
37~
l section positioning cycle to be en~aged by the vacuum head
60 which is then actuated to shift back across the web 31
as indicated by directional arrow 62 to guide the fastener
strip as engayed by the vacuum head 60 into position across
the web, as shown in FIG. 6. As thus positioned, the
cross-web section of the fastener strip 44 is secured to the
web 31 by fusion bonding or adhesive bonding, as may be
preferred. For example, where the web 31 and the ~astener ~.
strip 44 are of a fusion compatible material such as
polyethylene, direct fusion bonding may be effected. Where
the web 31 and the fastener strip 44 are not fusion
compatible, such as where the fastener strip 44 is a poly-
ethylene extrusion and the web 31, or at least the surface
of the web to which the fastener strip is to be bonded is
polypropylene, the base surface of the fastener strip 44
may carry heat reactivatable adhesive such as a hot melt
adhesive. Then, after the section of the fastener strip 44
that has been guided across the web 31 is in position to
be bonded to the web 31, a sealing head bar 63 underlying
the web 3l, in cooperation with a superjacent retaining and
pressure bar 64, effects fusion bonding, or reactivates the
adhesive carried by the base of the fastener strip, to secure
the fastener strip section permanently to the web 31. In
coordinated relation with its securement to the web 31 the
section of the fastener strip 44 is severed from the strip
supply as by means of a cutoff device 65.
After bonding of the notched fastener strip section 44
to the web 31, and which bonding may be effected in a dwell
in the advance of the web 31 coordinated with operation of
the form, fill and seal machine 28, the sealing bar 63 and
the retaining pressure bar 64 are released, and the vacuum
-13-
~%~87~
head 60 is released, and the web 45 may be advanced a bag
length section toward the machine 28. In order to avoid
damage to the profiles 52 of the fastener section 44 now
bonded to the web 31, as that section passes the feed rolls
47, the roll 47 which engages the fastener strip carrying
face of the web 31 may be covered with a relatively soft
friction material sleeve 67.
Desirably, at the upstream side of the fastener
strip securing means or station, a pair of pinch type guide
rolls 68 extend across and uniformly engage the web 31 and
in cooperation with the feed rolls 47 at the downstream side
of the station maintain a slight stretching tension on the
area of the web 31 between the rolls 47 and the rolls 68 to
facilitate attainment of optimum results in the fastener
strip assembling and bonding steps.
Although as shown in FIGS. 1, 5 and ~, the
longitudinal fin assembly 34 may be located on one wall of
the bag 20, in this instance on the wall 24, and onto which
the fin assembly may be bent over during the bag end cross
sealing effected by the sealing and pull down bars 39, the
longitudinal sealing may alternatively be effected along one
side of the bag as shown in FIG. 9. For this purpose, the
vertical sealing bars 35 are locat~d along what will become
one side of the bag and the lonyitudinal sealing thus
effected may be permitted to remain as that side of the bag.
In such event, only one V-notch 53 need be scored or cut in
each bag section of the fastener strip 44, with such notch
located to be at the opposite side of the bag, that is
directly opposite the fin assembly 34.
On the other hand, if desired, the vertical
closure seal for the bag material may be effected by lapping
D
7~
the longitudinal margins of the web into laminar relation
generally in the plane of the tubular form inta which the
web is shaped about the forming and filling nozzle cylinder.
To effect such a seal, a technique, substantially as ;
exemplified in US Patent 3,789,888 may be employed wherein a
single vertical sealing bar carried by a swing arm may be
employed. For this technique, the web margins are wrapped
into overlapping relation and each succeeding bag section
has the overlapped margins sealed together in what may be
the fin assembly 34, with the adjacent ends of the fastener
strip 44 at the lapped vertical seal along one wall of the
bag. Also for this arrangement the dual V-notches 53 are
utilized across the fastener profiles.
Instead of the vacuum head and sealing bar
applicator arrangement of FIG. 4 for assembling and securing
the fastener strip 44 to the web 31, a rotary fastener strip
applicator 71 as exemplified in FIG. 13 may be employed. For
this purpose, the applicator 71 comprises a rotary drum 72
which is adapted to be rotatably driven in step-by-step
coordination with a form, fill and seal apparatus as
exemplified in FIG. 5, where it is desired to apply fastener
strips 44' to the web 31 at a location adjacent to such a
machine. On the other hand, if it is desired to preform a
large endless sheet quantity of the bag making web 31
equipped with fastener strip sections 44' secured across the
longitudinal forming axis of the web for future use, the
applicator drum 72 may be rotated continuously for applying
the strip sections 44' to the continuously travelling web at
bag length intervals. In any event, the drum 72 is
-15-
1~ 4Q
1 provided at peripherally spaced intervals such as quadrantly
with axially extendiny pockets 73 receptive of the desired
length of fastener section 44'. At a loading station, a
loader 74 loads the proper length fastener strip section
into one of the pockets 73, with the profiles 52 extending
inwardly toward the root of the channel-lik~ pocket. A
pneumatic means comprising a vacuum source may be applied
to the pocket 73 being loaded to assure firm retention of
the fastener strip 44' therein. The loaded pocket then
moves with rotation of the drum 72 to a heating station
where means such as a heating roll 75 heats the exposed
base of the fastener strip. Such heating may be simply to
preheat the base for direct fusion to the web 31, or it may
be for the purpose of reactivating a reactivatable adhesive
carried by the base of the strip. From the heating station,
the strip is carried on by rotation of the drum 72 for
application to the web 31. For this purpose, a heated
rotatably driven roll 77 may be provided to underly the
web 31 in nipping relation to the drum 72 and the pxeheated
fastener strip is brought into position in the roll nip for
bonding to the web 31. At this point, pneumatic explusion
pressure may be applied to the strip carrying pocket 73 to
apply a firm uniform bonding pressure to the strip backed
up by the roll 77. ~he bonded fastener strip then leaves
the pocket 73, and the pocket advances toward the loading
station to be reloaded with another strip 44'.
An advantage of the rotary applicator 71 is that the
fastener strip sections 44' may be of any preferred
differential in length relative to the width of the web 31.
As shown in FIG. 14, for example, the fastener s~rip sections
44' may be shorter than the width of the web so as to leave
a marginal area 78 along each longitudinal edge of the weh
-16-
` ~2~387~L~
1 between such edge and the adjacent erld of the fastener
strip 44' in each instance and with the fastener strip
sections 44' located at the desired spacing 79 along the
length of the web 31. At suitable intervals along the
length of each of the fastener strips ~4', notches 53'
similar to the notches 53 in FIG. 11, are formed across the
profiles of the fastener strip to facilitate bending along
lines 55' when the bag making material assembly is formed
into bags. Since the margins 78 of the material are free
along the entire longitudinal length of the web 31, over-
lapping of such margins during hag formation is facilitated
for sealed seam closure, in the manner described in relation
to FIG. 10.
It will be appreciated, that if instead of having
the fastener strip foldable onto themselves as has been
described, for example as described in connection with
FIGS. 11 and 12, complementary fastener strips may be
secured across the formation axes of separate longitudinally
extending web sheets or panels and the sheets or panels
then brought into face-to-face relation with one another
and with the complementary fastener strips aligned for
reclosable bag interengagement in the bags made from the
material. Equipping the web with the fastener strips at
relatively high speed and to continuously running web may
be ef~ected by means of the applicator 71.
; Where the fastener-carrying web material is fed to a
bag making apparatus immediately after securing of the
fastener strips thereto, a second rotary applicator may be
provided for applying complementary fastener strips to a
second running web and the two w~bs carrying the comple-
mentary fastener strips being then joined downstream from
the applicators in the bag making process line.
-17-
` lZ1~374~
1 Where it is desired to provide a reclosable fastener
bag with bag making material such ~s represented in FIGS. 11
and 12, but further equipped with means for securing a
substantially air tight closure, the arrangement shown in
FIG. 15 may be employed wherein the bag material is provided
adjacent to the separable fastener, or as part of the separ-
able fastener, with a closed cell elastomer sealing rib 80
folded upon itself together with the associated fastener
strip 44 and adapted when the fastener profiles 52 are
snapped together to presssealingly together substantially
D as shown. In one preferred form, the close~cell elastomer
sealing rib 80 may be applied as a coextrusion onto a flange
extension 81 along the side of the strip 44 which will be
located at the innerside of the bag.
On the other hand, an air sealing arrangement such
as shown in ~IG. 16 may be provided wherein complementary
profiled fastener strips 82 and 83 may be securad to the mouth
end portions of a reclosable bag 84 and with closed cell
elastomer sealing strips ribs 85 carried by the fastener
strips 8~ and 83 in a manner to press against one another in
the closed fastener condition of the assembly. In this
arrangement, the fastener strip 82 may have four profiles,
and the fastener strip 83 may carry three complementary
fastener profiles, of generally arrow shape as shown, and
which interhook with one another in the closed condition of
the fastener. If preferred a rib and groove arrangement for
the interlocking fastener profiles such as exemplified in
U.S. Patent 3,440,696 may be employed in the arrangement of
FIG. 16. It may also be noted that this U.S~ Patent 3,440,696
discloses techniques for providing air seal means.
g~2~
1 It will be apparent that although placing o the
extruded resiliently flexible plastic profile reclosable
fastener strips across the longitudinal formation axis of
the web greatly facilitates and improves the ba~ length
capability of form, fill and seal machine techniques, and
attains the important advantage of being able to utilize
single strip reclosable fastener means rather than the
conventional dual complementary fastener strip arrangements,
the single strip technique may also be utilized for reclosable
bags or other products where a foldable closure orientation
of the single strip closure means may be advantageous. For
this purpose the transversely notched profile arrangement as
particularly described in connection with FIGS. 11 and 12
may be utilized, or the fastener strip may be applied to the
web in sections derived from the same continuous supply
strip and properly aligned so that when the web is folded
the fastener strip sections will be in substantially matching,
and thoroughly interlockable relation.
Accordingly, it will be appreciated that the present
invention provides a new dimension for utilization of
extruded resiliently flexible plastic profile reclosable
fasteners. In addition, the present invention affords
substantial economies where dual complementary fastener
strips may be replaced by the single foldable strip technique
of the present invention.
It will be understood that variations and modifications
may be effected without departing from the spirit and scope
of the novel concepts of this invention.
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