U.S. patent application number 13/800019 was filed with the patent office on 2014-05-15 for apparatus for gluing the tail of a convolutely wound web material thereto.
The applicant listed for this patent is THE PROCTER & GAMBLE COMPANY. Invention is credited to Wesley Bernard BROKOPP, JR., David Mark RASCH, James Max SMITH.
Application Number | 20140131498 13/800019 |
Document ID | / |
Family ID | 50680754 |
Filed Date | 2014-05-15 |
United States Patent
Application |
20140131498 |
Kind Code |
A1 |
BROKOPP, JR.; Wesley Bernard ;
et al. |
May 15, 2014 |
APPARATUS FOR GLUING THE TAIL OF A CONVOLUTELY WOUND WEB MATERIAL
THERETO
Abstract
An apparatus and method for adhesively bonding the tail of a
convolutely wound log to the body is provided. The apparatus
comprises a tail identifying system, spray nozzle adhesive
application system and tail winding system. The spray nozzle
application system comprises a plurality of nozzles, each nozzle
having a discharge portion configured to spray a foaming adhesive
in a predetermined deposit pattern to form a line of adhesive. The
method comprises the steps of: providing a sealing station with a
tail identifying and a spray nozzle adhesive application system
comprising a plurality of nozzles; spraying the foaming adhesive,
each nozzle spraying the foaming adhesive in a predetermined
deposit pattern to form a line of adhesive; and reattaching the
tail to the body at the line of adhesive. A convolutely wound
material having a tail and a body, where the tail is bonded to the
body with foaming adhesive, is provided.
Inventors: |
BROKOPP, JR.; Wesley Bernard;
(Middletown, OH) ; SMITH; James Max; (West
Chester, OH) ; RASCH; David Mark; (Cincinnati,
OH) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
THE PROCTER & GAMBLE COMPANY |
Cincinnati |
OH |
US |
|
|
Family ID: |
50680754 |
Appl. No.: |
13/800019 |
Filed: |
March 13, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61725155 |
Nov 12, 2012 |
|
|
|
Current U.S.
Class: |
242/160.4 ;
156/184; 156/446; 242/160.1 |
Current CPC
Class: |
B65H 2301/414421
20130101; B65H 19/29 20130101; B65H 2301/414443 20130101; B65H
2301/414436 20130101; B65H 18/28 20130101 |
Class at
Publication: |
242/160.4 ;
156/446; 156/184; 242/160.1 |
International
Class: |
B65H 18/08 20060101
B65H018/08; B65H 18/28 20060101 B65H018/28; A47K 10/16 20060101
A47K010/16; B65H 18/00 20060101 B65H018/00 |
Claims
1. An apparatus for adhesively bonding a tail of a convolutely
wound log of web material to the body of the convolutely wound log
of web material, the apparatus comprising: a tail identifying
system for identifying the presence and position of the tail; a
spray nozzle adhesive application system positioned downstream from
the tail identifying system to receive the log from the tail
identifying system and comprising a plurality of nozzles, each
nozzle having a discharge portion configured to spray a foaming
adhesive in a predetermined deposit pattern at a respective spray
site on one of the tail or the body to form a line of adhesive on
said one of the tail or the body; and a tail winding system,
positioned downstream from the spray nozzle adhesive application
system to receive the log from the spray nozzle adhesive
application system, the tail winding system being capable of
joining the tail with the body at the line of adhesive.
2. The apparatus of claim 1, wherein the tail identifying system
further comprises a tail positioning component capable of
circumferentially displacing the tail from the body.
3. The apparatus of claim 1, wherein the predetermined deposit
pattern comprises a shape having an aspect ratio of about 2 or
more.
4. The apparatus of claim 1, wherein each nozzle is positioned at
an angle of from about 45 degrees to about 135 degrees relative to
the respective spray site.
5. The apparatus of claim 1, wherein each nozzle is positioned from
about 4 inches to about 16 inches away from the respective spray
site.
6. The apparatus of claim 1, wherein the plurality of nozzles is
configured such that there is at least one nozzle per about every
11 inches of width of the convolutely wound log of web
material.
7. The apparatus of claim 1, wherein each nozzle is positioned
generally below the respective spray site and is capable of
spraying the foaming adhesive in a generally upward direction.
8. The apparatus of claim 7, wherein each nozzle is positioned from
about 1 inch to about 16 inches away from the respective spray
site.
9. The apparatus of claim 7, wherein the apparatus is capable
bonding the tail to the body at a rate of not less than 20
convolutely wound logs processed/minute.
10. The apparatus of claim 1, wherein each nozzle further comprises
a body having a liquid inlet and an air inlet port, wherein the
liquid inlet port and the air inlet port are diametrically opposed,
a spray tip affixed the body, and an air cap disposed in
surrounding relation to the spray tip; wherein: the spray tip
comprises a nose portion and a liquid passageway, the liquid
passageway being capable of communicating with the liquid inlet
port and having a spray tip discharge orifice formed in the nose
portion; the air inlet port is capable of communicating with a
first air chamber defined between the body and the spray tip; the
air chamber is capable of communicating with a plurality of air
passageways formed in the spray tip, the air passageways being
disposed in circumferentially surrounding relation to the liquid
passageway and capable of communicating with a second air chamber,
the second air chamber being defined between the spray tip and the
air cap; the air cap comprises an internal mixing chamber and an
opening, the opening being disposed in a surrounding relation to
the nose portion such that an air orifice is defined between the
nose portion and the opening; the air orifice is capable of
communicating with the second air chamber; and the air orifice and
the spray tip discharge orifice are capable of communicating with
the internal mixing chamber simultaneously such that liquid from
the spray tip discharge orifice and air from the air orifice meet
in the internal mixing chamber and generate the foaming
adhesive.
11. A method for adhesively bonding a tail of a convolutely wound
log of web material to the body of the convolutely wound log of web
material, the method comprising the steps of: providing a sealing
station with a tail identifying system for identifying the presence
and position of the tail; providing the sealing station with a
spray nozzle adhesive application system comprising a plurality of
nozzles, each nozzle capable of spraying a foaming adhesive in a
predetermined deposit pattern at a respective spray site on one of
the tail or the body to form a line of adhesive on said one of the
tail or the body; spraying the foaming adhesive, each nozzle
spraying the foaming adhesive in the predetermined deposit pattern
at the respective spray site on the one of the tail or the body to
form the line of adhesive on the one of the tail or the body; and
reattaching the tail to the body at the line of adhesive.
12. The method of claim 11, wherein the method further comprises
the steps of: providing a tail positioning component for
circumferentially displacing the tail from the body; and
circumferentially displacing the tail from the body.
13. The method of claim 11, wherein the predetermined deposit
pattern comprises a shape having an aspect ratio of about 2 or
more.
14. The method of claim 11, wherein each nozzle is positioned at an
angle of about 45 degrees to about 135 degrees relative to the
respective spray site.
15. The method of claim 11, wherein each nozzle is positioned from
about 4 inches to about 16 inches away from the respective spray
site.
16. The method of claim 11, wherein the plurality of nozzles is
provided such that there is at least one nozzle per about every 11
inches of width of the convolutely wound log of web material.
17. The method of claim 11, each nozzle is positioned generally
beneath the respective spray site and wherein the step of spraying
the foaming adhesive further comprises each nozzle spraying the
foaming adhesive in a generally upward direction.
18. The method of claim 17, wherein each nozzle is positioned from
about 1 inch to about 16 inches away from the respective spray
site.
19. The method of claim 17, wherein the tail is bonded to the body
at a rate of not less than 20 convolutely wound logs
processed/minute.
20. A convolutely wound material having a tail and a body, the tail
being bonded to the body with a foaming adhesive.
21. The convolutely wound material of claim 20, wherein the tail
and body are bonded at a line of adhesive.
22. The convolutely wound material of claim 20, where the
convolutely wound material comprises a sanitary tissue product.
23. The convolutely wound material of claim 22, where the sanitary
tissue product comprises embossing.
24. The convolutely wound material of claim 23, wherein the
convolutely wound material further comprises a peak and a valley,
wherein the maximum height distance between the peak and the valley
is from about 365 .mu.m to about 1750 .mu.m.
25. The convolutely wound material of claim 23, wherein the
convolutely wound material further comprises a peak and a valley,
wherein the maximum height distance between the peak and the valley
is from about 180 .mu.m to about 780 .mu.m.
26. The convolutely wound material of claim 20, wherein the
convolutely wound material comprises a peel strength of about 50
g/11 inch roll to about 400 g/11 inch roll, or alternatively 2.5
g/inch of consumer-sized product unit to about 36.4 g/inch of
consumer-sized product unit, at about 5 minutes to about 7 minutes
after application of the foaming adhesive.
Description
FIELD OF THE INVENTION
[0001] The present disclosure provides for an apparatus and method
for gluing the tail or other end of a convolutely wound log of web
material thereto in order to form a roll suitable for consumer
use.
BACKGROUND OF THE INVENTION
[0002] In the manufacture of rolled web products, such as bath
tissue or paper towels, a winder winds a web of material to form a
large parent roll. The parent roll is then subsequently unwound,
subjected to a variety of conversions, such as embossing, and then
rewound by a rewinder into a consumer diameter sized convolutely
wound log. The convolutely wound log is eventually cut into
consumer width sized rolls, such as bath tissue, paper towels and
similar finished products. To efficiently process the convolutely
wound log through converting processes, cutting and packaging, the
loose end of the log (i.e., the tail) is often secured or sealed to
the body (i.e., the non-tail portion).
[0003] Common gluing, moistening and other systems known to those
in the tail gluing art typically require some manipulation of the
tail for correct alignment in adhesive application, proper winding
or rewinding and the like. In most commercially available
embodiments, the tail is laid flat and unwrinkled against the log
with the tail being secured to the log at a position a short
distance from the very end of the tail. This tail sealing
arrangement leaves a small length of the end of the tail unsecured
(the so-called "tab") to enable the end user to grasp, unseal and
unwind the convolutely wound product.
[0004] Known methods and systems for tail sealing face many
undesirable results. For example, many systems dispense excess
adhesive that is not picked up by the convolutely wound roll. Such
excess adhesive is often recovered in an underlying tank and made
to flow back into the system. Other known systems incorporate a
bath or pool of adhesive which is provided in an open condition. In
both situations, the systems allow dust, debris and other foreign
matter to be incorporated into the adhesive, thus polluting the
adhesive flow stream and/or reducing the effectiveness of the
adhesive upon subsequent rolls. Such systems typically incorporate
filtration systems in an effort to remove such pollutants from the
adhesive stream. Such filtration systems add increased cost to the
systems as well as provide routine maintenance issues.
[0005] Many known systems also have been found deficient when
attempting to obtain a sufficient amount of adhesion. Adhesion
problems may arise due to substrate specifications and
enhancements, such as high topography or strength-inducing
chemicals. Modern papermaking and embossing techniques have been
able to provide web substrates that have a high degree of
deflection in the direction orthogonal to the plane formed by the
web substrate. Many known systems can utilize only the portions of
the substrate having a high degree of deflection as a suitable
bonding area because the portions of the substrate having a low
degree of deflection are unavailable or less available to serve as
contact points between surfaces sought to be connected. This
limited bonding area has resulted in insufficient adhesion because
of limited opportunities for adhesive contact. Strength-inducing
chemistries utilized in producing paper web substrates also
contribute to adhesion issues. Manufacturers are increasingly
incorporating strength-inducing chemicals to substrates to enhance
quality. Yet, such chemicals may interfere with the bonding of
adhesives in tail sealing.
[0006] Further, adhesion issues have arisen from the type of
adhesive and method of application. Indeed, known systems often
emit adhesives in such a manner that the adhesives penetrate below
the surface of the paper web substrate as opposed to residing on
the surface. Adhesive absorbed below the surface results in less
adhesive being available for bonding at the surface and therefore
less adhesion.
[0007] Moreover, known tail gluing systems often utilize adhesive
that dries slower than desired. It is desirable that tail seal
adhesive dry quickly, so that the bond is set in time for
downstream converting operations (e.g., wrapping, bundling, etc.).
A log typically is processed through such processes in about 5-10
minutes. Yet, known systems utilize adhesives with drying times of
more than an hour--which fully dry long after the product is cycled
through the manufacturing processes. In such cases, manufacturers
often rely on temporary bonding primarily attributable to cohesive
bonding within the adhesive, which is typically substantially lower
than the final strength of the adhesive when it is fully dried
(i.e., after sufficient time has passed to achieve maximum
bonding).
[0008] Insufficient drying and/or bonding also can occur based on
heavy localized application of the adhesive, where the adhesive is
concentrated in particular areas due to the application design. The
formulation of the adhesive may contribute to adhesion problems as
well, with many typical formulations containing about 85% to 97%
water. Water not only inhibits drying but also interferes with
bonding.
[0009] The lack of sufficient adhesion produces manufacturing
problems such as tearing, wrinkled tails, unsightly bonding areas
and/or delays in production due to loose tails. To compensate for
deficient bonding, manufacturers have over-applied adhesive to the
tail to create some sense of quick adhesion, which is mostly due to
the internal cohesive strength of the glue itself Yet, this can
result in negative end user feedback because, once the adhesive
completely dries, the tail becomes difficult to remove from the
roll and can cause the separation of plies and/or tearing of
sheets.
[0010] In addition, tail sealing processes struggle with precise
placement of adhesive to create the tab of the tail and ensure the
roll does not become unsightly due to the tail sealed portion.
[0011] Thus, it would be advantageous to provide for a tail gluing
system that addresses one or more of these issues. Indeed, it would
be advantageous to minimize or even eliminate the prospect of
contamination of the adhesive. It would also be useful to provide
for a tail gluing system that increases adhesive efficiency, such
that it provides sufficient bonding for substrates having high
surface topography (despite the limited available bonding area)
and/or substrates with strength-inducing chemistries. Likewise, it
would be beneficial to provide for a system that reduces both the
amount of adhesive required and the drying time necessary to
provide suitable bonding. Additionally, it would be beneficial to
provide a tail sealing system that reduces negative end user
feedback and/or allows for adhesive to be applied in a pattern.
Finally, it would be advantageous to provide for a tailing sealing
system that increases throughput, reduces the components required
to operate effectively and provides for a mechanism that reduces
the maintenance required upon such a tail gluing system.
SUMMARY OF THE INVENTION
[0012] The present invention fulfills the needs described above by
providing an apparatus for adhesively bonding the tail of a
convolutely wound log of web material to the body of the log, where
the apparatus comprises a tail identifying system for identifying
the presence and position of the tail, a spray nozzle adhesive
application system positioned downstream from the tail identifying
system to receive the log from the tail identifying system and a
tail winding system positioned downstream from the spray nozzle
adhesive application system to receive the log from the spray
nozzle adhesive application system. The spray nozzle adhesive
application system may comprise a plurality of nozzles, each nozzle
having a discharge portion configured to spray a foaming adhesive
in a predetermined deposit pattern at a respective spray site on
either the tail or the body. The predetermined deposit patterns may
combine to form a line of adhesive on the tail or the body. The
tail winding system may be capable of joining the tail to the body
at the line of adhesive.
[0013] In another embodiment, a method for adhesively bonding a
tail of a convolutely wound log of web material to the body of the
log is provided. The method may comprise the steps of: providing a
sealing station with a tail identifying system for identifying the
presence and position of the tail; providing the sealing station
with a spray nozzle adhesive application system comprising a
plurality of nozzles, each nozzle being capable of spraying a
foaming adhesive in a predetermined deposit pattern at a respective
spray site on the tail or the body. The method may further comprise
the step of spraying the foaming adhesive, each nozzle spraying the
foaming adhesive in a predetermined deposit pattern at a respective
spray site on the tail or the body to form a line of adhesive on
the tail or the body. Further, the method may include the step of
reattaching the tail to the body at the line of adhesive.
[0014] In yet another embodiment, a convolutely wound material
having a tail and a body, where the tail is bonded to the body with
a foaming adhesive, is provided.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a cross-sectional view of an exemplary typical
tail sealing apparatus;
[0016] FIG. 2 is cross-sectional view of an exemplary tail sealing
apparatus in accordance with on embodiment of the present
disclosure;
[0017] FIG. 3 is a cross-sectional view of an exemplary typical
tail sealing apparatus;
[0018] FIG. 4 is a cross-sectional view of an exemplary tail
sealing apparatus in accordance with one embodiment of the present
disclosure;
[0019] FIG. 5 is a perspective view of a plurality of spray nozzles
according to an embodiment of the present disclosure;
[0020] FIG. 6 is a cross-sectional view of a spray nozzle adhesive
application system in accordance with one embodiment of the present
disclosure;
[0021] FIG. 7 is a cross-sectional view of an exemplary spray
nozzle system in accordance with the present disclosure;
[0022] FIG. 8 is a plan view of the spray nozzle system of FIG.
7;
[0023] FIG. 9 is a cross-sectional view of an exemplary nozzle
suitable for use with the present disclosure;
[0024] FIG. 10 is a plan view of the exemplary nozzle of FIG.
9;
[0025] FIG. 11 is a schematic representation of a method for tail
sealing according to an embodiment of the present disclosure;
[0026] FIG. 12 is a schematic representation of an exemplary
material according to one embodiment of the present disclosure;
[0027] FIG. 13 is a graph displaying wet strength tail seal values
in accordance with one embodiment of the present disclosure;
and
[0028] FIG. 14 is a cross-sectional view of a consumer-sized
convolutely wound roll of web material according to one embodiment
of the present disclosure.
DETAILED DESCRIPTION
[0029] The present disclosure provides for equipment, methods and
products using foaming adhesive for tail sealing a convolutely
wound log of material. Various nonlimiting embodiments of the
present disclosure will now be described to provide an overall
understanding of the principles of the function, design and use of
the tail sealing apparatuses and methods as well as the tail sealed
convolutely wound products disclosed herein. One or more examples
of these nonlimiting embodiments are illustrated in the
accompanying drawings. Those of ordinary skill in the art will
understand that the apparatuses, methods and products described
herein and illustrated in the accompanying drawings are nonlimiting
example embodiments and that the scope of the various nonlimiting
embodiments of the present disclosure are defined solely by the
claims. The features illustrated or described in connection with
one nonlimiting embodiment can be combined with the features of
other nonlimiting embodiments. Such modifications and variations
are intended to be included within the scope of the present
disclosure.
Definitions
[0030] "Fibrous structure" as used herein means a structure that
comprises one or more filaments and/or fibers.
[0031] Nonlimiting examples of processes for making fibrous
structures include known wet-laid papermaking processes and
air-laid papermaking processes. Such processes typically include
steps of preparing a fiber composition in the form of a suspension
in a medium, either wet, more specifically aqueous medium, or dry,
more specifically gaseous, i.e. with air as medium. The aqueous
medium used for wet-laid processes is oftentimes referred to as a
fiber slurry. The fibrous slurry is then used to deposit a
plurality of fibers onto a forming wire or belt such that an
embryonic fibrous structure is formed, after which drying and/or
bonding the fibers together results in a fibrous structure. Further
processing the fibrous structure may be carried out such that a
finished fibrous structure is formed. For example, in typical
papermaking processes, the finished fibrous structure is the
fibrous structure that is wound on the reel at the end of
papermaking and may subsequently be converted into a finished
product (e.g., a sanitary tissue product such as a paper towel
product).
[0032] The fibrous structures of the present invention may be
homogeneous or may be layered. If layered, the fibrous structures
may comprise at least two and/or at least three and/or at least
four and/or at least five layers.
[0033] The fibrous structures of the present invention may be
co-formed fibrous structures.
[0034] "Fiber" and/or "Filament" as used herein means an elongate
particulate having an apparent length greatly exceeding its
apparent width (i.e., a length to diameter ratio of at least about
10). In one example, a "fiber" is an elongate particulate as
described above that exhibits a length of less than 5.08 cm (2 in.)
and a "filament" is an elongate particulate as described above that
exhibits a length of greater than or equal to 5.08 cm (2 in.).
[0035] Fibers are typically considered discontinuous in nature.
Nonlimiting examples of fibers include wood pulp fibers and
synthetic staple fibers such as polyester fibers.
[0036] Filaments are typically considered continuous or
substantially continuous in nature. Filaments are relatively longer
than fibers. Nonlimiting examples of filaments include meltblown
and/or spunbond filaments. Nonlimiting examples of materials that
can be spun into filaments include natural polymers, such as
starch, starch derivatives, cellulose and cellulose derivatives,
hemicellulose, hemicellulose derivatives, and synthetic polymers
including, but not limited to polyvinyl alcohol filaments and/or
polyvinyl alcohol derivative filaments, and thermoplastic polymer
filaments, such as polyesters, nylons, polyolefins such as
polypropylene filaments, polyethylene filaments, and biodegradable
or compostable thermoplastic fibers such as polylactic acid
filaments, polyhydroxyalkanoate filaments and polycaprolactone
filaments. The filaments may be monocomponent or multicomponent,
such as bicomponent filaments.
[0037] In one example of the present invention, "fiber" refers to
papermaking fibers. Papermaking fibers useful in the present
invention include cellulosic fibers commonly known as wood pulp
fibers. Applicable wood pulps include chemical pulps, such as
Kraft, sulfite, and sulfate pulps, as well as mechanical pulps
including, for example, groundwood, thermomechanical pulp and
chemically modified thermomechanical pulp. Chemical pulps, however,
may be preferred since they impart a superior tactile sense of
softness to tissue sheets made therefrom. Pulps derived from both
deciduous trees (hereinafter, also referred to as "hardwood") and
coniferous trees (hereinafter, also referred to as "softwood") may
be utilized. The hardwood and softwood fibers can be blended, or
alternatively, can be deposited in layers to provide a stratified
web. Also applicable to the present invention are fibers derived
from recycled paper, which may contain any or all of the above
categories as well as other non-fibrous materials such as fillers
and adhesives used to facilitate the original papermaking
[0038] "Sanitary tissue product" as used herein means a soft, low
density (i.e., <about 0.15 g/cm.sup.3) web useful as a wiping
implement for post-urinary and post-bowel movement cleaning (toilet
tissue), for otorhinolaryngological discharges (facial tissue) and
multi-functional absorbent and cleaning uses (absorbent towels).
The sanitary tissue product may be convolutely wound upon itself
about a core or without a core to form a sanitary tissue product
roll.
[0039] The sanitary tissue products and/or fibrous structures of
the present invention may exhibit a basis weight of greater than 15
g/m.sup.2 (9.2 lbs/3000 ft.sup.2) to about 120 g/m.sup.2 (73.8
lbs/3000 ft.sup.2) and/or from about 15 g/m.sup.2 (9.2 lbs/3000
ft.sup.2) to about 110 g/m.sup.2 (67.7 lbs/3000 ft.sup.2) and/or
from about 20 g/m.sup.2 (12.3 lbs/3000 ft.sup.2) to about 100
g/m.sup.2 (61.5 lbs/3000 ft.sup.2) and/or from about 30 (18.5
lbs/3000 ft.sup.2) to 90 g/m.sup.2 (55.4 lbs/3000 ft.sup.2). In
addition, the sanitary tissue products and/or fibrous structures of
the present invention may exhibit a basis weight between about 40
g/m.sup.2 (24.6 lbs/3000 ft.sup.2) to about 120 g/m.sup.2 (73.8
lbs/3000 ft.sup.2) and/or from about 50 g/m.sup.2 (30.8 lbs/3000
ft.sup.2) to about 110 g/m.sup.2 (67.7 lbs/3000 ft.sup.2) and/or
from about 55 g/m.sup.2 (33.8 lbs/3000 ft.sup.2) to about 105
g/m.sup.2 (64.6 lbs/3000 ft.sup.2) and/or from about 60 (36.9
lbs/3000 ft.sup.2) to 100 g/m.sup.2 (61.5 lbs/3000 ft.sup.2).
[0040] The sanitary tissue products of the present invention may
exhibit a total dry tensile strength of greater than about 59 g/cm
(150 g/in) and/or from about 78 g/cm (200 g/in) to about 394 g/cm
(1000 g/in) and/or from about 98 g/cm (250 g/in) to about 335 g/cm
(850 g/in). In addition, the sanitary tissue product of the present
invention may exhibit a total dry tensile strength of greater than
about 196 g/cm (500 g/in) and/or from about 196 g/cm (500 g/in) to
about 394 g/cm (1000 g/in) and/or from about 216 g/cm (550 g/in) to
about 335 g/cm (850 g/in) and/or from about 236 g/cm (600 g/in) to
about 315 g/cm (800 g/in). In one example, the sanitary tissue
product exhibits a total dry tensile strength of less than about
394 g/cm (1000 g/in) and/or less than about 335 g/cm (850
g/in).
[0041] In another example, the sanitary tissue products of the
present invention may exhibit a total dry tensile strength of
greater than about 196 g/cm (500 g/in) and/or greater than about
236 g/cm (600 g/in) and/or greater than about 276 g/cm (700 g/in)
and/or greater than about 315 g/cm (800 g/in) and/or greater than
about 354 g/cm (900 g/in) and/or greater than about 394 g/cm (1000
g/in) and/or from about 315 g/cm (800 g/in) to about 1968 g/cm
(5000 g/in) and/or from about 354 g/cm (900 g/in) to about 1181
g/cm (3000 g/in) and/or from about 354 g/cm (900 g/in) to about 984
g/cm (2500 g/in) and/or from about 394 g/cm (1000 g/in) to about
787 g/cm (2000 g/in).
[0042] The sanitary tissue products of the present invention may
exhibit an initial total wet tensile strength of less than about 78
g/cm (200 g/in) and/or less than about 59 g/cm (150 g/in) and/or
less than about 39 g/cm (100 g/in) and/or less than about 29 g/cm
(75 g/in). The sanitary tissue products of the present invention
may exhibit an initial total wet tensile strength of greater than
about 118 g/cm (300 g/in) and/or greater than about 157 g/cm (400
g/in) and/or greater than about 196 g/cm (500 g/in) and/or greater
than about 236 g/cm (600 g/in) and/or greater than about 276 g/cm
(700 g/in) and/or greater than about 315 g/cm (800 g/in) and/or
greater than about 354 g/cm (900 g/in) and/or greater than about
394 g/cm (1000 g/in) and/or from about 118 g/cm (300 g/in) to about
1968 g/cm (5000 g/in) and/or from about 157 g/cm (400 g/in) to
about 1181 g/cm (3000 g/in) and/or from about 196 g/cm (500 g/in)
to about 984 g/cm (2500 g/in) and/or from about 196 g/cm (500 g/in)
to about 787 g/cm (2000 g/in) and/or from about 196 g/cm (500 g/in)
to about 591 g/cm (1500 g/in).
[0043] The sanitary tissue products of the present invention may
exhibit a density (measured at 95 g/in.sup.2) of less than about
0.60 g/cm.sup.3 and/or less than about 0.30 g/cm.sup.3 and/or less
than about 0.20 g/cm.sup.3 and/or less than about 0.10 g/cm.sup.3
and/or less than about 0.07 g/cm.sup.3 and/or less than about 0.05
g/cm.sup.3 and/or from about 0.01 g/cm.sup.3 to about 0.20
g/cm.sup.3 and/or from about 0.02 g/cm.sup.3 to about 0.10
g/cm.sup.3.
[0044] The sanitary tissue products of the present invention may
comprise additives such as softening agents, such as quaternary
ammonium softening agents, temporary wet strength agents, permanent
wet strength agents, bulk softening agents, lotions, silicones,
wetting agents, latexes, dry strength agents, and other types of
additives suitable for inclusion in and/or on sanitary tissue
products.
[0045] The embodiments discussed herein may be utilized with a
convolutely wound log of web material, such as a convolutely wound
log of a fibrous structure. The fibrous structure may comprise a
sanitary tissue product.
[0046] "Consumer-sized product unit" as used in herein means the
width of a finished product of convolutely wound web material, as
measured in the cross machine direction, as such product will be
sold, distributed or otherwise provided to end users.
[0047] "Spray site" as used herein means the desired location at
which adhesive emitted from a given nozzle in accordance the
present disclosure is to be deposited on the web material. The
spray site may be located on the tail, the body (i.e., the non-tail
portion of the log) or the crevice where the tail and the body
meet.
[0048] "Machine direction" or "MD" as used herein means the
direction parallel to the flow of the web material through the
manufacturing equipment.
[0049] "Cross machine direction" or "CD" as used herein means the
direction parallel to the width of the manufacturing equipment and
perpendicular to the machine direction.
[0050] The Z-direction is orthogonal both the machine direction and
cross machine direction, such that the machine direction, cross
machine direction and Z-direction form a Cartesian coordinate
system.
[0051] "Line of adhesive" as used herein means a macroscopically
linear shape that may be essentially continuous (or unbroken) or
semi-continuous (wherein the line of adhesive is intermittent, such
as a dotted line). In one embodiment of the present invention, the
line of adhesive extends in the cross machine direction. As used
herein, a shape is "macroscopically linear" if, when viewed with
the unaided human eye at a distance of about 12 inches, such shape
appears to form a substantially straight line (continuous or
semi-continuous) or a substantially repeating pattern (continuous
or semi-continuous).
[0052] "Above", "over", "top", "up", "below", "beneath", "bottom"
and "under" and similar orientational words and phrases, except
upstream and downstream, as used herein to describe embodiments are
to be construed relative to the normal orientation, where the floor
is located in the Z-direction below, beneath or under a tail
sealing apparatus and the ceiling is located in the Z-direction
above or over a tail sealing apparatus. Articles expressed as being
above, over, on top and the like are located (or moving) in the
Z-direction closer to the ceiling than the items to which they are
being compared. Similarly, articles expressed as being below,
beneath or under and the like are located (or moving) in the
Z-direction closer to the floor than their respective comparators.
One of skill in the art will recognize that the relationship
between the article and its respective comparator is more
significant than the relationship between the article and the floor
or the ceiling. As such, inverted arrangements of articles as
disclosed herein are included within the scope of this disclosure.
Said differently, to the extent such configurations are workable,
this disclosure is intended to include an apparatus and/or method
where everything expressed as "below" is inverted to be "above" and
everything expressed as "above" is inverted to be "below" and
similar reversals or inversions.
[0053] "Downstream" as used herein means a step or system occurring
or present later in a processing continuum. "Upstream" as used
herein means a step or system occurring or present earlier in a
processing continuum.
Typical Tail Sealers
[0054] A short description of typical tail sealers follows to
provide context for the present invention.
[0055] A. Typical Spray Application Style
[0056] As shown in FIG. 1, an exemplary prior art tail sealer is a
"conventional spray system" style 10. In a conventional spray
system 10, the tail sealer apparatus is mounted directly downstream
of a rewinder and is an integral part of a converting operation.
Generally, the apparatus 10 is provided with a: 1. Log in-feed; 2.
Log index to sealing station; 3. Tail detection and positioning; 4.
Spray application of adhesive; 5. Tail rewinding; and 6. Log
discharge. An exemplary conventional spray system sealer 10 is the
T30-Spray.RTM. tail sealing apparatus, commercially available from
Paper Converting Machine Co.
[0057] As shown in FIG. 1, in an exemplary conventional spray
system 10, the log 12 enters through the in-feed conveyer 14. An
in-feed kicker 16 then indexes the log 12 into a plurality of
rotating turn rollers 18. The log 12 settles between turn rollers
18, and the turn rollers 18 rotate the log 12 in place. A blow pipe
20 emits a burst of air, causing the tail 22 to separate from the
body 13 of the log 12 and move towards a table 24. As the turn
rollers 18 continue to rotate the log 12, the tail 22 moves within
range of the tail detection mechanism 26 (e.g., a photo eye sensor)
and rests on or near the table 24. Once the tail 22 is detected, a
plurality of glue guns 28 simultaneously emit liquid adhesive at an
application pressure of about 2,000 psi and a viscosity of about
15,000 cps to about 23,000 cps.
[0058] The number of glue guns 28 may correspond to the number of
finished consumer-sized product units anticipated to be cut from
the log 12. For example, there may be nine glue guns 28 for a log
12 expected to produce nine finished consumer-sized product units
(i.e., one glue gun per position of the anticipated finished
product). Adhesive may cause build up on saws that are used to cut
the log 12 into consumer-sized product units. It is believed that
less liquid adhesive will be found on the areas that will be cut by
the saws if only one glue gun is positioned to cover one
anticipated consumer-sized product unit. This reduces the amount of
overlapping deposits of adhesive at the cutting areas.
Consequently, the amount of adhesive the saw may encounter during
cutting the log 12 into consumer-sized product units is reduced as
is the likelihood for build up.
[0059] The glue guns 28 are arranged such that they extend through
the width of the log 12 in the cross machine direction and may be
positioned above the table 24 at an angle of about 90 degrees
relative to the table 24, or any other angle suitable to emit the
glue at the desired location. After the glue is applied, the turn
rollers 18 continue to roll, causing the tail 22 to rewind and
reconnect to the body 13 as the weight of the log 12 presses the
tail 22 and body 13 together. After the tail 22 is reconnected to
the log 12, an auxiliary kicker 30 ejects the log 12 toward the
next converting operation--typically an accumulator in-feed.
Conventional spray system tail sealers 10 may operate at a rate of
up to about 22 logs processed/minute. Such systems 10 may include
timers and/or other control features to manage the rate of
operation and/or prevent backlog or overfeeding of the logs 12 into
the tail sealer 10.
[0060] B. Typical Blade-In-Pan or Plate Style Apparatus
[0061] As shown in FIG. 3, an exemplary prior art tail sealer is a
"blade-in-pan" or "plate" style tail sealer 100 that provides an
in-line style tail sealer. As with the conventional spray system
style 10, the tail sealer apparatus in the blade-in-pan style 100
is also mounted directly downstream of a rewinder and is an
integral part of a converting operation. Likewise, the apparatus
100 has many of the same basic steps of the conventional spray
system 10, except a blade, bar or wire operation exists in lieu of
the spray application step. In other words, the apparatus 100 for
applying an adhesive to a convolutely wound log of web material is
provided with a: 1. Log in-feed; 2. Log index to sealing station;
3. Tail detection and positioning; 4. A "blade-in-pan" or "plate
style" adhesive application; 5. Tail rewinding; and 6. Log
discharge. An exemplary blade-in-pan or plate style tail sealer 100
is the ROTOSEAL.RTM. tail sealing apparatus, commercially available
from Paper Converting Machine Co. Other examples of a typical plate
style tail sealer include the 560C.RTM. and 561 DLX.RTM. tail
sealing apparatus models, both commercially available from Fabio
Perini S.p.A.
[0062] As shown in FIG. 3, the log 120 enters at the in-feed
conveyor 140. An incoming log detector 160 (e.g., a photo eye
sensor) detects when the log 120 is in position on the in-feed
conveyor 140 and activates a rotary kicker 180 that pushes the log
120 off the conveyor 140 toward the index paddle 200. The index
paddle 200 receives the log 120 and holds it until the in-feed
rolls 210 are clear. The index paddle 200 then indexes about 90
degrees, moving the log 120 into the in-feed rolls 210. In-feed
rolls 210 will typically comprise an upper in-feed roll 212 and a
lower in-feed roll 214 (typically a vacuum roll).
[0063] The in-feed rolls 210 initially rotate in the same direction
but at mismatched speeds, with the upper in-feed roll 212 rotating
faster than the lower in-feed (or vacuum) roll 214. The distance of
upper in-feed roll 212 relative to lower in-feed roll 214 can be
adjusted to accommodate the log 120 diameter. However, the upper
in-feed roll 212 is typically positioned to create some
interference with the log 120. When the log 120 is fed into the
in-feed rolls 210, the log 120 may be controlled at the top and
bottom log 120 positions because of the interference and rate of
log 120 travel is controlled by the speed difference between the
in-feed rolls 210. If there is too little or no interference, the
log 120 could slide through the in-feed rolls 210. Conversely, if
there is too much interference, the logs 120 may not feed into the
in-feed rolls 210 correctly and could cause a jam up at the index
paddle 200.
[0064] As the log 120 contacts the in-feed rolls 210, it is pulled
into the nip between the in-feed rolls 210 by the differential
speed. As the log 120 reaches the diagonal center of the in-feed
rolls 210, it blocks the log in-feed rollers detector 216 (e.g.,
photo eye sensor) at which time the in-feed rolls 210 rotate at a
matched speed. This holds the log 120 in position while an airblast
nozzle 259 emits a stream of air to separate the tail 220 from the
log 120 and position the tail 220 flat onto the table 240 where a
tail detector 260 (e.g., a PEC) becomes blocked by the tail 220. As
the log 120 rotates and rewinds the separated tail 220, the tail
detector 260 becomes unblocked when the edge of the tail 220 has
been located.
[0065] After the edge of the tail 220 is detected, the tail 220 is
rewound onto the log 120 until the edge of the tail 220 is directly
underneath the body 130 of the log 120. The in-feed rolls 210 stop
and reverse direction, which unrolls the tail 220 from the body
130. The tail 220 is held by vacuum to the lower in-feed roll 214
and follows the lower in-feed roll 214 as it is unwound until a
calculated length of tail 220 has been separated from the body 130.
The in-feed rolls 210 then stop and the upper in-feed roll 212
starts rotating back in the forward direction to eject the body 120
from the in-feed rolls 210. The tail length centerline controls the
amount of tail 220 that is unwound from the log 120 and is
typically adjusted to get the target tab length. The speed of
in-feed rolls 210 can impact consistent tail detection. Higher
speeds can reduce the time to rotate the log 120 but may not
increase rate capability. The speed of in-feed rolls 210 can be
adjusted to consistently detect the tail 220 on the first
revolution.
[0066] While the tail 220 is being detected, the glue blade (or bar
or wire) 280 of the blade-in-pan assembly (or bar or wire and pan
assembly) 290 is submerged in the glue pan 292. After the tail of
log 220 is detected, the glue blade 280 is raised out of the glue
pan 292 and is timed so that the body 130 rolls over glue blade 280
after being ejected from the in-feed rolls 210. After the log 120
passes, the glue blade 280 is lowered back into the glue pan 292.
The glue blade 280 height can be adjusted so that the top of the
glue blade 280 is slightly higher than the adjacent table 240.
[0067] After glue application, the log 120 rolls down the table 240
to the out-feed rolls 294 which compress the tail 220 to the body
130. The lower out-feed roll 296 runs slower than the upper
out-feed roll 298, which moves the log 120 through the out-feed
rolls 294 for a controlled duration, similar to the in-feed rolls
210. The lower out-feed roll 296 speed is controlled as a
percentage of the upper out-feed roll 298 speed. More closely
matching the upper out-feed roll 298 and lower out-feed roll 296
speeds will allow the out-feed rolls 294 to hold the log 120
longer.
[0068] When the log 120 is released from the out-feed rolls 294, it
rolls down the table 240 to the next converting
operation--typically an accumulator in-feed. A typical blade-in-pan
style tail sealer 100 may operate at a rate of not less than about
20 logs processed/minute, or at rate of about 30 to about 60 logs
processed/minute, or a rate of about 50 to about 60 logs
processed/minute.
Spray Application of Foamed Adhesive
[0069] In one embodiment of the present invention, the tail sealer
apparatus 10a, 100a may involve some of the same components as the
description above in combination with a tail identifying system for
identifying the presence and position of the tail, a spray nozzle
application system 400 that is capable of spraying a foaming
adhesive 406 in a predetermined pattern to form a line of adhesive
402 and a tail winding system capable joining the tail 12a, 120a to
the body 13a, 130a at the line of adhesive 402. In one embodiment,
the tail sealer 10a, 100a may include a tail positioning component
that is capable of circumferentially displacing the tail 22a, 220a
from the body 13a, 130a. The tail positioning component may be part
of the tail identifying system.
[0070] In one nonlimiting example, as shown in FIG. 2, a tail
sealing apparatus 10a has an in-feed conveyer 14a where the log 12a
enters the tail seal apparatus 10a. An in-feed kicker 16a may then
index the log 12a into a plurality of rotating turn rollers 18a.
The log 12a may then settle between turn rollers 18a, and the turn
rollers 18a may rotate the log 12a in place. A blow pipe 20a can
emit a burst of air, causing the tail 22a to separate from the log
12a and move towards a table 24a. The turn rollers 18a can continue
to rotate the log 12a, such that the tail 22a moves within range of
the tail detection mechanism 26a (e.g., a photo eye sensor) and
rests on or near the table 24a generally beneath the spray nozzle
application system 400.
[0071] In an alternative embodiment, the tail sealer 10a may
identify the tail 22a by using a counting mechanism. In one
nonlimiting example, the tail sealer 10a is capable of anticipating
the tail 22a by counting the number of sheets processed through the
system. The apparatus 10a may count the number of sheets required
to produce the desired log 12a and identify the tail 22a as the
last sheet in the count.
[0072] Once the tail 22a is detected, the spray nozzle application
system 400 may emit a line of adhesive 402. The log 12a may be held
stationary while the line of adhesive 402 is being emitted or the
log 12a may be moving.
[0073] In one embodiment, the spray nozzle application system 400
includes a nozzle 404 that is capable of dispensing a foaming
adhesive 406 and that has a discharge portion 408. The discharge
portion 408 may be configured to spray the foaming adhesive 406 in
a predetermined deposit pattern. Such predetermined deposit pattern
may form part of the line of adhesive 402. In one nonlimiting
example, the discharge portion 408 is configured to spray the
foaming adhesive 406 such that it will deposit on a spray site in a
generally two-dimensional circular pattern. In another nonlimiting
example, the deposit pattern may be generally two-dimensionally
ovular. In yet another nonlimiting example, the discharge portion
408 is configured such that the deposit pattern has a
two-dimensional shape, such as an oval, egg shape or ellipse,
having an aspect ratio of about 1.1 or more, or about 2 or more.
For purposes of this disclosure, the aspect ratio of a shape is
measured in the MD-CD plane and is the ratio of the length of the
longest dimension or diameter of the shape, in any direction, that
intersects the shape's midpoint and length of the shortest
dimension or diameter of the shape, in any direction, that
intersects the shape's midpoint.
[0074] The configuration of the discharge portion 408 may be a
function of the several factors, including but not limited to spray
pressure and velocity, the distance between the discharge portion
408 and the spray site and/or table 24a, the angle of the discharge
portion 408 relative to the spray site and/or table 24a, the
desired density of the adhesive applied or the desired deposit
pattern.
[0075] In one embodiment, the nozzle 404 is positioned at an angle
of about 45 degrees to about 135 degrees relative to the spray
site. In another embodiment, the nozzle 404 is positioned at an
angle of about 45 degrees to about 135 degrees relative to the
table 24a. In a further embodiment, the nozzle 404 is positioned
from about 4 to about 16 inches from the spray site, or from about
6 inches to about 12 inches from the spray site, or from about 6
inches to about 8 inches from the spray site. In yet another
embodiment, the nozzle is positioned from about 4 to about 16
inches from the table 24a, or from about 6 to about 12 inches from
the table 24a, or from about 6 inches to about 8 inches from the
table 24a.
[0076] For purposes of this disclosure, angles and/or distances
from the spray site are measured as follows: Where the spray site
is found on the tail 22a, 220a, the distance and/or the angle of
the nozzle 404 in relation to the spray site is measured from the
outermost edge 410 of the discharge portion 408 to the plane of a
section of the spray site that is macroscopically monoplanar. As
used herein a section is "macroscopically monoplanar" if such
section appears to be contained within one plane when viewed with
the unaided human eye at a distance of about 12 inches.
[0077] Where the spray site is found on the body 13a, 130a, the
distance and/or the angle of the nozzle 404 in relation to the
spray site is measured from the outmost edge 410 of the discharge
portion 408 to a plane created by a tangent line running through
the circumference of the body 13a, 130a at the point most proximate
to the outmost edge 410 of the discharge portion 408.
[0078] Where the spray site is found in the crevice where between
the tail 22a, 220a and the body 13a, 130a, the distance and/or
angle of the nozzle 404 in relation to the spray site is measured
from the outmost edge 410 of the discharge portion 408 to a point
within of the spray site where the tail 22a, 220a and the body 13a,
130a meet.
[0079] In yet another embodiment, the spray nozzle application
system 400 comprises a plurality of nozzles 404 of the present
disclosure that are mounted or otherwise connected to the tail
sealing apparatus 10a such that they are substantially spaced apart
in a generally linear manner in the cross machine direction. In
another embodiment, the nozzles 404 may be positioned in a pattern
such that they do not form a straight line in the cross machine
direction. In one embodiment, the plurality of nozzles 404 includes
from about 9 to about 12 nozzles for about a 100-inch log 12a as
measured in the cross machine direction. In another embodiment,
there is at least one nozzle 404 per about every 11 inches of the
log 12a as measured in the cross machine direction, or per about
every 8 inches of the log 12a as measured in the cross machine
direction. In one embodiment, the number of nozzles 404 is
equivalent to the anticipated number finished consumer-sized
product units expected to be produced. In other words, if nine
finished products were to be created from one log 12a, then nine
nozzles 404 may be used. In another embodiment, the number of
nozzles 404 is greater than the number of anticipated finished
consumer-sized product units, as the foaming adhesive 406 does not
create the same potential for build up log saws as seen with
conventional tail sealers 10. In one nonlimiting example, the
nozzles 404 are equidistant from each other. In an alternative
nonlimiting example, the distances between adjacent nozzles 404 may
vary throughout the plurality. In a further nonlimiting example,
each nozzle 404 may be positioned between about 4 inches and about
16 inches, or between about 6 inches to about 12 inches, or between
about 6 inches to about 8 inches from a respective spray site upon
which it will deposit the foaming adhesive 406 and/or from a table
24a. In another embodiment, each nozzle 404 may be positioned about
45 degrees to about 135 degrees relative to the respective spray
site upon which it may deposit the foaming adhesive 406 or about 45
degrees to about 135 degrees relative to the table 24a. It is
believed that in combination at a given pressure, the nozzles 404
may create a relatively long, thin line of adhesive 402.
[0080] A line of adhesive 402 may be formed by a combination of the
emissions from a plurality of spray guns, which may include one or
more nozzles 404 of the present disclosure. In one nonlimiting
example, the line of adhesive 402 extends through the width of the
log 12a and/or the tail 22a as measured in the cross machine
direction. In one nonlimiting example, the line of adhesive 402 may
be formed by overlapping predetermined deposit patterns from
nozzles 404 of the present disclosure. In another nonlimiting
example, the line of adhesive 402 is formed from adjacent,
connecting predetermined deposit patterns from the nozzles 404. In
yet another nonlimiting example, the line of adhesive 402 is formed
from a series of unconnected predetermined deposit patterns from
such nozzles 404. The line of adhesive 402 may also be formed by a
combination of the foregoing examples. In yet another embodiment,
the line of adhesive 402 is in elongated elliptical pattern.
[0081] Without being bound by theory, it is believed that the
dimensions of the desired line of adhesive 402 are a function of
several factors including the type of spray guns, the number of
spray guns, each spray gun's fan angle, the distance of the spray
guns from the spray site, the angle of the spray guns relative to a
respective spray site, the pressure and velocity at which the
foaming adhesive is sprayed, the anticipated pattern of emission of
the adhesive (such as the predetermined deposit pattern of a nozzle
404 of the present invention) and the desired density of the
adhesive in the line 402. One of skill in the art will recognize
that such variables can be adjusted in a number of possible
combinations to accomplish the desired line of adhesive 402.
[0082] After the line of adhesive 402 is deposited, turn rollers
18a may continue to roll, causing the tail 22a to rewind and
reconnect to the body 13a. Alternatively, the body 13a and the tail
22a may be wound together for the first time after the line of
adhesive 402 has been deposited. The body 13a and the tail 22a may
be connected at the line of adhesive 402.
[0083] The weight of the log 12a may be used to press the tail 22a
and body 13a together. In an alternative embodiment, an arm or
other machine part may be used to compress the tail 22a and the
body 13a together. In another nonlimiting example, air and/or a
change in pressure can be used to press the tail 22a and the body
13a together. Those of skill in the art will recognize that such
compression may be achieved in different ways.
[0084] After the tail 22a is reconnected to the log 12a, an
auxiliary kicker 30a may eject the log 12a toward the next
converting operation--such as an accumulator in-feed. Timers and/or
other control features may be used to manage the rate of operation
and/or prevent backlog or overfeeding of the logs 12a into the tail
sealer 10a.
[0085] In another embodiment, shown in FIG. 4, the nozzle 404 of
the present disclosure is inverted such that the nozzle 404 may
spray the foaming adhesive 406 in a generally upward direction. The
spray site can be positioned generally above the nozzle 404. The
inverted spray nozzle 404 may be placed in the area generally where
a blade, bar or wire and pan assembly 290 could be found in
exemplary typical tail sealers 100.
[0086] In one nonlimiting example, as illustrated in FIG. 4, the
log 120a may enter the tail sealer 100a at in-feed conveyor 140a.
An incoming log detector 160a can detect when the log 120a is in
position on the in-feed conveyor 140a and activate a rotary kicker
160a to push the log 120a off the conveyor 140a toward the index
paddle 200a. The index paddle 200a can then receive the log 120a
and hold it until the in-feed rolls 210a are clear. The index
paddle 200a may then index about 90 degrees, moving the log 120a
into the in-feed rolls 210a. In-feed rolls 210a may comprise an
upper in-feed roll 212a and a lower in-feed roll 214a (such as a
vacuum roll).
[0087] The in-feed rolls 210a may initially rotate in the same
direction but at mismatched speeds, with the upper in-feed roll
212a rotating faster than the lower in-feed (or vacuum) roll 214a.
The distance of upper in-feed roll 212a relative to lower in-feed
roll 214a can be adjusted to accommodate the log 120a diameter.
However, upper in-feed roll 212a may be positioned to create some
interference with the log 120a. When the log 120a is fed into the
in-feed rolls 210a, the log 120a may be controlled at the top and
bottom log 120a positions because of the interference and rate of
log 120a travel is controlled by the speed difference between the
in-feed rolls 210a. If there is too little or no interference, the
log 120a could slide through the in-feed rolls 210a. Conversely, if
there is too much interference, the logs 120a may not feed into the
in-feed rolls 30a correctly and could cause a jam up at the index
paddle 200a.
[0088] As the log 120a contacts the in-feed rolls 210a, it is
pulled into the nip between the in-feed rolls 210a by the
differential speed. As the log 120a reaches the diagonal center of
the in-feed rolls 210a, it blocks the log in-feed rollers detector
216a (e.g., photo eye sensor) at which time the in-feed rolls 210a
rotate at a matched speed. This holds the log 120a in position
while an airblast nozzle 259a may emit a stream of air to separate
the tail 220a from the log 120a and position the tail 220a flat
onto the table 240a where a tail detector 260a (e.g., a PEC) can
become blocked by the tail 220a. As the log 120a rotates and
rewinds the separated tail 220a, the tail detector 260a becomes
unblocked when the edge of the tail 220a has been located.
[0089] After the edge of the tail 220a is detected, the tail 220a
may be rewound onto the body 130a until the edge of the tail 220a
is directly underneath the body 130a. The in-feed rolls 210a may
then stop and reverse direction, resulting in the tail 220a
unrolling from body 130a. The tail 220a may then be held by vacuum
to the lower in-feed roll 214a and follow the lower in-feed roll
214a as it is unwound until a calculated length of tail 220a has
been separated from the body 130a. The in-feed rolls 210a can then
stop and the upper in-feed roll 212a can start rotating back in the
forward direction to eject the log 120a from the in-feed rolls
210a. The tail length centerline can control the amount of tail
sheet 220a that is unwound from the log 120a and be adjusted to get
the desired tab length. In one nonlimiting example, the tab length
is about 1 inch as measured from the edge of the tail 220a in the
machine direction. The speed of in-feed rolls 210a may be adjusted
to achieve consistent tail detection. Higher speeds can reduce the
time to rotate the log 120a but may not increase rate capability.
The speed of in-feed rolls 210a can be adjusted to consistently
detect the tail 220a on the first revolution.
[0090] In an alternative embodiment, the tail sealer 100a may
identify the tail 220a by using a counting mechanism. In one
nonlimiting example, the tail sealer 100a is capable of
anticipating the tail 220a by counting the number of sheets
processed through the system. The apparatus 100a may count the
number of sheets required to produce the desired log 120a and
identify the tail 220a as the last sheet in the count.
[0091] After the tail 220a is detected, the spray nozzle
application system 400 may spray a line of adhesive 402. The spray
nozzle application system 400 may be provided underneath a table
240a. The log 120a may be held stationary while the line of
adhesive 402 is being emitted or the log 120a may be moving.
[0092] In one nonlimiting example, the nozzle 404 may emit a stream
of foamed adhesive 406 onto a spray site in a generally upward
direction through an aperture 300a disposed within table 240a. The
discharge portion 408 of the nozzle 404 may be configured to emit
the foaming adhesive 406 in a predetermined deposit pattern. Such
predetermined deposit pattern may form part of the line of adhesive
402. In one nonlimiting example, the discharge portion 408 is
configured to spray the foaming adhesive 406 such that it will
deposit on a spray site in a generally two-dimensional circular
pattern. In another nonlimiting example, the deposit pattern may be
generally two-dimensionally ovular. In yet another nonlimiting
example, the discharge portion 408 is configured such that the
deposit pattern has a two-dimensional shape, such as an oval, egg
shape or ellipse, having an aspect ratio (in a two-dimensional
context) of about 1.1 or more, or about 2 or more. The aspect ratio
is measured as explained above.
[0093] The nozzle 404 may be provided at an angle relative to the
table 240a ranging from about 45 degrees to about 135 degrees in
order to allow for the rolling progression of a log 120a through
the tail sealer apparatus 100a and achieve a suitable line of
adhesive 402. In another embodiment, the nozzle 404 is positioned
at an angle of about 45 degrees to about 135 degrees relative to
the spray site. In a further embodiment, the nozzle 404 is
positioned from about 1 to about 16 inches from the spray site, or
from about 3 to about 4 inches from the spray site. Measurements of
such angles and distances are to be performed as explained
above.
[0094] In yet another embodiment, shown in FIG. 5, the spray nozzle
application system 400 comprises a plurality of nozzles 404 of the
present disclosure that are mounted or otherwise connected to the
tail sealing apparatus 100a such that are positioned generally
beneath the table 240a and/or respective spray sites. In another
embodiment, the nozzles 404 are substantially spaced apart in a
generally linear manner in the cross machine direction. In yet
another embodiment, the nozzles 404 may be positioned in a pattern
such that they do not form a line in the cross machine direction.
In a nonlimiting example, the plurality of nozzles 404 comprises
from about 12 to about 33 nozzles 404, or from about 27 to about 33
nozzles 404 for about a 100-inch log 120a as measured in the cross
machine direction. In another embodiment, there is at least one
nozzle 404 per about every 11 inches of the log 120a as measured in
the cross machine direction. In one embodiment, the number of
nozzles 404 is equivalent to the anticipated number of final
finished products expected to be produced. In other words, if nine
finished products were to be created from one log 120a, then nine
nozzles 404 may be used. In another embodiment, the number of
nozzles 404 is greater than the number of anticipated final
finished products, as the foaming adhesive 406 does not create the
same potential for build up on the log saw as seen with
conventional tail sealers 10, 100. In a nonlimiting example, each
nozzle 404 may be positioned between about 1 and about 16 inches,
or about 3 to about 4 inches from a respective spray site upon
which it will deposit the foaming adhesive 406. In one nonlimiting
example, the nozzles 404 are equidistant from each other. In an
alternative nonlimiting example, the distances between adjacent
nozzles 404 may vary throughout the plurality. In a further
embodiment, each nozzle 404 may be positioned about 45 degrees to
about 135 degrees relative to the respective spray site upon which
it may deposit the foaming adhesive 406 or from about 45 degrees to
about 135 degrees relative to the table 240a. It is believed that
in combination at a given pressure, the nozzles 404 may create a
relatively long, thin line of adhesive 402.
[0095] A line of adhesive 402 may be formed by a combination of the
emissions from a plurality of spray guns, which may include one or
more nozzles 404 of the present invention. In one nonlimiting
example, the line of adhesive 402 extends through the width of the
log 120a and/or the tail 220a as measured in the cross machine
direction. In one nonlimiting example, the line of adhesive 402 may
be formed by overlapping predetermined deposit patterns from
nozzles 404 of the present disclosure. In another nonlimiting
example, the line of adhesive 402 is formed from adjacent,
connecting predetermined deposit patterns from the nozzles 404. In
yet another nonlimiting example, the line of adhesive 402 is formed
from a series of unconnected predetermined deposit patterns from
such nozzles 404. The line of adhesive 402 may also be formed by a
combination of the foregoing examples. In yet another embodiment,
the line of adhesive 402 is in elongated elliptical pattern.
[0096] Without being bound by theory, it is believed that the
dimensions of the desired line of adhesive 402 are a function of
several factors including the type of spray guns, the number of
spray guns, each spray gun's fan angle, the distance of the spray
guns from the spray site, the angle of the spray guns relative to a
respective spray site, the pressure and velocity at which the
foaming adhesive is sprayed, the anticipated pattern of emission of
the adhesive (such as the predetermined deposit pattern of a nozzle
404 of the present invention) and the desired density of the
adhesive in the line 402. One of skill in the art will recognize
that such variables can be adjusted in a number of possible
combinations to accomplish the desired line of adhesive 402.
[0097] After application of the foaming adhesive 406, the log 20a
may roll down the table 240a to the out-feed rolls 210a which may
press the tail 220a to the body 130a. The body 130a may be
reconnected to the tail 220a at the line of adhesive 402. The lower
out-feed roll 296a may run slower than the upper out-feed roll
298a, causing the log 120a to move through the out-feed rolls 294a
for a controlled duration, similar to the in-feed rolls 210a. The
speed of lower out-feed roll 296a may be controlled as a percentage
of the speed of upper out-feed roll 298a. Increasing the setting
will more closely match the upper out-feed roll 298a and lower
out-feed roll 296a speeds. This can hold the log 120a in the
out-feed rolls 294a longer.
[0098] When the log 120a is released from the out-feed rolls 294a,
it can roll down the table 240a to the next converting
operation--typically an accumulator in-feed.
[0099] In an alternative embodiment, the tail 220a and body 130a
may be compressed using an arm or other type of machine part to
press pieces together. In another nonlimiting example, air and/or a
change of pressure may be used to cause the body 130a and the tail
220a to press together. One of skill in the art will recognize that
compression can be achieved in different ways.
[0100] In yet another embodiment, the body 130a and the tail 220a
may be wound together for the first time after the line of adhesive
402 has been deposited. The body 130a and the tail 220a may be
connected at the line of adhesive 402.
[0101] The spray nozzle application system 400 of the present
disclosure may bond the tail 220a at a rate that allows the tail
sealer 100a to process logs 120a at a rate not less than 20 logs
processed/minute, or at a rate between about 30 logs
processed/minute to about 60 logs processed/minute, or from about
50 logs processed/minute to about 60 logs processed/minute. It was
discovered that technical improvements of the adhesive components
of the tail sealer 100a did not result in rate reduction. This
solves the problem of the expected rate decrease based on
improvements to the adhesive system.
[0102] As one of skill in the art will recognize, other
arrangements of portions of the exemplary tail sealers 10a, 100a
can be used. For instance, the relative speeds of the upper in-feed
rolls 212a and lower in-feed rolls 214a may be changed, the table
24a, 240a placement as well as the presence of a log in-feed
section, log index to sealing station, tail identifying, tail
winding and log discharge portions may be modified. As a
nonlimiting example, belts may be used in lieu of rolls. Likewise,
the angles and distances of the nozzle 404 relative to the spray
site and/or table 24a, 240a may be altered as may the application
pressure or velocity. Additionally, timers and/or other control
features may be used to manage the rate of operation and/or prevent
backlog or overfeeding of the logs 12a, 120a into the tail sealer
10a, 100a.
[0103] Further, the skilled person can recognize different
arrangements, presentation or placement of the various components
of this disclosure may be used to achieve the desired density of
adhesive 406 and/or line of adhesive 402.
Foamed Adhesive Spray Nozzle
[0104] FIGS. 6-9 illustrate an exemplary spray nozzle application
system 400 shown in a configuration where the foamed adhesive 406
would be sprayed in a generally upward position. The spray nozzle
application system 400 generally may comprise a nozzle 404, air
valve 412, adhesive supply 414, inert gas (e.g., air) supply 416
and control lines 418. It was found that the nozzle 404 and an air
valve 412 could be intimately connected so that the solenoids
disposed within the air valve 412 may control the rate of inert gas
entering the chamber of the nozzle 404 in a controlled fashion.
This control was found suitable to allow for the production of
convolutely wound logs 12a, 120a of web material in traditional
bath tissue and paper toweling manufacturing operations.
[0105] In function, an inert gas may be presented at the outside
position of a solenoid provided internally to air valve 412. As a
log 12a, 120a is detected by the tail identifying system, the
solenoid within the air valve 412 may open and pressurize the
nozzle 404 with inert gas from the inert gas supply 416. Another
solenoid disposed internally to the nozzle 404 may then open to
allow the egress of adhesive from the adhesive supply 414 and inert
gas from the inert gas supply 416 into the nozzle 404 where
integral mixing can occur.
[0106] Referring now to FIGS. 9-10, there is shown one nonlimiting
example of a foam generating nozzle 404 in accordance with the
present invention. The nozzle 404 may include a nozzle body 311
formed with diametrically opposed liquid inlet 312 and pressurized
air inlet ports 314, a nozzle spray tip 315 affixed to the forward
or downstream end of the nozzle body 311 by a threaded stem 316 of
the nozzle spray tip 315, and an air cap 318 disposed in
surrounding relation to the nozzle spray tip 315 and retained
thereon by a retaining nut 319. The nozzle spray tip 315 may have a
liquid passageway 320 extending along a central axis 321 of the
nozzle 404 and communicating with the liquid inlet port 312. The
liquid passageway 320 may include a relatively large diameter
upstream portion 320a and an inwardly tapered conical portion 320b
that communicates with a relatively small diameter discharge
orifice 320c formed in a forwarding extending relatively small
diameter, cylindrical nose portion 322 of the nozzle spray tip
315.
[0107] The nozzle 404 can be mounted to a rod 325 positioned into a
mounting opening 326 in a rear side of the nozzle body 311 in
coaxial alignment with the central liquid passageway 320. It will
be appreciated by one skilled in the art that alternatively the
nozzle body 311 can be supported by other means and the central
rear opening 326 may receive a valve needle for controlling the
liquid flow through the spray nozzle 404 under the control of a
pneumatically actuated piston, such as disclosed in U.S. Pat. No.
5,899,387. While in the illustrated embodiment, the nozzle body 311
and nozzle spray tip 315 are separate parts, it also will be
understood that alternatively they may be formed as an integral
single part.
[0108] The air inlet port 314 in this instance communicates with a
first annular air chamber 330 defined between the nozzle body 311
and nozzle spray tip 315, which in turn communicates with a
plurality of inwardly tapered air passageways 331 formed in the
nozzle spray tip 315 in circumferentially spaced relation about the
central liquid passageway 320. The nozzle spray tip air passageways
331 each communicate with a second air chamber 332, which may be
conically configured and annular. The second air chamber 332 may be
defined between the upstream side of the air cap 318 and a
downstream inwardly tapered end of the nozzle spray tip 315.
[0109] In one embodiment, the air cap 318 has a central opening 335
disposed in surrounding relation to the spray tip nose portion 322,
which defines an annular air orifice 336 that communicates between
the tapered second air chamber 332 and an internal mixing chamber
338 of the air cap 318. The air cap 318 may be further formed with
the plurality of circumferentially spaced discharge orifices 339
which each communicate with the internal air cap mixing chamber
338. Hence, the direction of pressurized liquid and air to the
inlet ports 312, 314, respectfully, can result in the simultaneous
discharge of liquid from the nozzle spray tip discharge orifice
320c and pressurized air from the annular air discharge orifice 336
for intermixing within the mixing chamber 338 and ultimate
discharge through the plurality of the air cap discharge orifices
339.
[0110] In accordance with one aspect of the illustrated embodiment
of the invention, the air cap internal mixing chamber 338 may be
larger in diameter than the annular air discharge orifice 336 so as
to permit enhanced intermixing and pre-atomization of the
pressurized liquid and air streams directed into the internal
mixing chamber 338 prior to discharge from the circumferentially
spaced air discharge orifices 339. The air cap mixing chamber 338
may have a diameter of at least 30% greater than the outer diameter
of the annular air discharge orifice 336, or at least 50% greater,
so as to permit intermixing of the liquid and air streams in an
area both downstream and radially outwardly of the pressurized
liquid and air streams directed into the mixing chamber 338. In the
illustrated embodiment, the internal air cap mixing chamber 338 may
be defined by a cylindrical wall 341 of the air cap 318 having a
conically configured downstream end 342 and an annular insert 344
positionable in an upstream end of the air cap 318 that defines the
central air cap opening 336.
[0111] The air cap discharge orifices 339 can extend in skewed
relation to the central axis 321 of air cap 318 and nozzle spray
tip liquid passageway 320, which unexpectedly has been found to
minimize negative pressures between the discharging flow streams
and reduce undesirable bearding of solid particulate material on
external surfaces of the air cap 318, while enhancing intermixing
of the flow streams discharging from the air cap discharge orifices
339. As used in the specification and claims, the term "skewed"
means that the axes 340 of the discharge orifices 339 are oriented
at an compound angle with respect to the central air cap and liquid
passageway axis 321, namely at an acute angle both to a horizontal
plane extending through the central axis 321 of the nozzle and a
vertical plane extending through the central axis 321 of the air
cap 318. With the flow streams discharging from the air cap 318
directed both radially and tangentially with respect to the central
air cap axis 321, the fine pre-atomized liquid particles tend to
migrate more readily into a full cone spray pattern.
[0112] In keeping with still a further feature of this embodiment
of the invention, the relatively large diameter internal air cap
mixing chamber 338 and the skewed relation of the air cap discharge
orifices 339 enable the air cap 318 to be formed with a greater
number of discharge orifices 339, which may additionally facilitate
intermixing of the discharging liquid particles into a full spray
pattern with reduced negative pressures between the discharging
flow streams. The closer spacing between the skewed discharge
orifices 339 is believed to both facilitate intermixing of the
discharging flow stream into a conical spray pattern and minimize
negative pressure between the discharging flow streams which
otherwise create undesirable bearding of solid particulate material
on the air cap 318.
[0113] The nozzle 404 design permits foaming adhesive 406 to be
generated just before emission, such that foam 406 will not need to
be stored within the nozzle 404 for a period of time. Storage of
foam 406 inside a nozzle could lead to difficulties in generating
additional foam due to lack of available space and build up from
foam 406 residue.
[0114] The referenced nozzle 404 may be provided with a fluid at
about 10 psi to about 60 psi and air at about 10 psi to about 60
psi.
[0115] A nozzle suitable for use with the tail sealer 10a, 100a for
the present disclosure is Pulse-Jet AA10000JJAU-VI (applicator
nozzle gun) in combination with applicator tip parts PFJ60100-SS
FLUID CAP,SS,1/8JJ and SPECCP98327-SS SPECIAL 70DEGREE AIR CAP, all
of which are available from Spraying Systems Co. One of skill in
the art will recognize that the nozzles of the present invention
may be used in combination with other known sprayers.
Foaming Adhesive
[0116] A suitable adhesive 406 for the present invention may be
aqueous and capable of forming a fine bubble foam when pressurized
or otherwise atomized at the conditions discussed above. It may
also comprise preservatives. In an embodiment, the adhesive 406 may
comprise foaming control agents to control the type and amount of
foam.
[0117] The adhesive 406 may be water-based. In another embodiment,
the adhesive 406 may comprise polyvinyl alcohol. In an alternative
embodiment, the adhesive 406 may be starch-based, such as a
polysaccharide or polyhydroxyl composition. Typically, polyvinyl
alcohol-based and starch-based adhesives are known to demonstrate
poor releasability, which can result in negative feedback when end
users attempt to remove the tail 22a, 220a from the body 13a, 130a.
It was surprising found, however, that polyvinyl alcohol or
starch-based adhesives in combination with a foaming agent as used
in the present disclosure work well as a tail sealing adhesive 406
due to reasons discussed below.
[0118] The adhesive 406 may have a viscosity of about 450 cps to
about 550 cps, or about 500 cps, at point of delivery into the
nozzle 404. The adhesive 406 may have a pH of about 2.5 to about
5.5, or from about 3 to about 5, or a pH of about 4. The adhesive
406 can have about 30% to about 44% solids content, or about 36% to
about 38% solids content, or about 37% solids content. Typical tail
seal adhesives (outside of the scope of the present invention) may
comprise 3-15% solids. Nonlimiting examples of suitable adhesives
are TT5000B.RTM., TT5000BX.RTM. or TT5001, all of which are
available from HB Fuller Company.
[0119] In one embodiment, air is provided as the gas material
and/or foaming agent.
[0120] It is believed that foaming the adhesive 406 significantly
increases adhesive efficiency for a combination of reasons. First,
the density of any given volume of adhesive 406 is reduced by
replacing it with a gas (e.g., air), so the amount of adhesive 406
used may be decreased compared to typical tail sealing adhesives.
Second, the foamed adhesive 406 is distributed in droplets, each
droplet having less glue than particles of non-foaming adhesives.
The viscosity and consistency of the adhesive 406 results in the
size of each droplet being more uniform as compared to non-foaming
tail seal adhesives. Third, the droplets' lower density permits the
droplets to be distributed onto the web material in a generally
uniform manner when emitted from the nozzle 404 versus a
distribution of a non-foaming adhesive. As such, the foaming
adhesive 406 can reach more surface area than a non-foamed
adhesive.
[0121] Fourth, foaming adhesive 406 may comprise significantly less
water than comparative non-foaming adhesives. Indeed, because less
adhesive is used and faster drying times are achievable, adhesive
formulations that typically would result in excessive bonding and
releasability issues, such as polyvinyl alcohols and starches, can
be used successfully. As a result, less water may be used.
Moreover, the increased solid content versus non-foaming adhesives
may result in up to about 75% less water being used.
[0122] Fifth, the foamed adhesive 406 may permit drying at a
relatively fast rate compared to known tail sealing processes. In
one nonlimiting example, the foamed adhesive 406 of the present
disclosure may dry within about 1 minute to about 5 minutes, or
about 1 minute to about 2 minutes. It is believed that the rapid
drying is a function of the structure of the foam 406, which
generally may have more uniform particle size compared to
non-foamed adhesive. The uniform particle size is believed to
permit more consistent and thorough drying as each particle is
expected to dry in generally the same amount of time. Moreover, it
is believed that the foam 406 structure permits internal and
external drying because air is entrapped inside each particle and
air flows on the outside of each particle as well. Such dual
internal/external drying may permit accelerated drying when
compared to non-foamed adhesive. In addition, the reduced water
content contributes to quicker drying as well. The faster drying
time permits maximum bonding during the converting processes as
opposed to typical tail seal adhesives which achieve maximum bond
strength after such processes are complete.
[0123] Sixth, the reduced water content in each droplet and lower
density enables each droplet to stay more on the surface of the web
substrate where bonding is desired. Non-foaming adhesives tend to
be pulled into the web material by capillary forces which pull
water and thereby adhesive into the structure of the sheet.
Adhesive within the structure of the web material is unavailable or
significantly less available for bonding, causing adhesive benefits
to be significantly reduced.
[0124] All of these factors result in increased adhesive efficiency
compared to existing tail glue processes. In other words, more
effective bonding may be achieved with less adhesive. In one
nonlimiting example, adhesive quantity was reduced by about 80 to
about 90% as compared to known tail sealing adhesives. Such
increased adhesive efficiency is achievable even where there is
limited available bonding area. Moreover, the use of less adhesive
406 as well as lighter density adhesive 406 (as compared to
non-foaming adhesives) results in less potential for build up on
log saws used to cut logs 12a, 120a into finished consumer-sized
product units.
[0125] In one embodiment, the available bonding area is limited by
Z-direction textures on the web material, such as texture created
by embossing. In one nonlimiting example, the convolutely wound
material 600 has a peak 602 and a valley 604. In some instances,
the peak 602 is the only available bonding area as the valley 604
is positioned too far away from body 13a, 130a and/or tail 22a,
220a to which it is being bonded and/or because the pressure used
for compressing the body 13a, 130a and/or tail 22a, 220a is not
sufficient to allow the valley 604 to reach the area to which it is
to be bonded. This is especially true in instances where only the
weight of the log 12a, 120a provides compression pressure for
pressing the tail 22a, 220a and the body 13a, 130a together. The
foaming adhesive 406, for the reasons described herein, may
increase the number of adhesive contact points on the surface of
the peak 602, within a given spray site of the web material. As a
result, more efficient bonding may be achieved as compared to
non-foaming adhesive.
[0126] It is also believed that the faster dry time reduces the
tackiness of the adhesive in a manner that significantly reduces
the amount of time that any airborne contaminants (such as debris
and dust) have the opportunity to contaminate the applied adhesive.
It is also believed that the use of inert gas in a mechanical
foaming process is a more sustainable solution than chemical
multi-component foaming processes, many of which produce VOCs or
employ isocyanates.
Method of Applying Foaming Adhesive
[0127] In one embodiment of the present disclosure, a method 500
for tail sealing is provided. A schematic illustration of the steps
that may be involved is shown in FIG. 11. The steps may be
performed in the order disclosed or in any other order suitable for
tail sealing a convolutely wound log of web material 12a, 120a. An
initial step 510 may comprise providing a convolutely wound log
12a, 120a to a sealing station or another suitable portion of a
tail sealer. In one embodiment, the method 500 includes a sealing
station step 512, comprising providing a sealing station having a
tail identifying system. The sealing station may further comprise a
tail positioning component capable of circumferentially displacing
the tail 22a, 220a from the body 13a, 130a by, for example,
emitting air or liquid to displace the tail 22a, 220a. In another
nonlimiting example, the tail identifying system may include an arm
or other suitable structure to push or pull the tail 22a, 220a away
from the body 13a, 130a. In yet another nonlimiting example, the
tail identifying system may include a vacuum or similar suction
apparatus which may draw the tail 22a, 220a away from the body 13a,
130a. The tail positioning component may be part of the tail
identifying system.
[0128] The method 500 may further comprise a spray system step 514
of providing the sealing station with a spray nozzle adhesive
application system 400. The spray nozzle adhesive application
system 400 may be capable of spraying a line of adhesive 402. The
spray nozzle adhesive application system 400 may also comprise a
plurality of nozzles 404, each nozzle 404 capable of spraying a
foaming adhesive 406 in a predetermined deposit pattern. The method
500 may also comprise a displacing step 516 of circumferentially
displacing the tail 22a, 220a from the body 13a, 130a. In one
nonlimiting example, the displacing step 516 may be accomplished
using the tail positioning component.
[0129] In another embodiment, the displacing step 516 is
unnecessary as the tail 22a, 220a and the body 13a, 130a are not
initially connected and therefore they do not require separation.
In one nonlimiting example, the tail 22a, 220a may be identified by
using a counting mechanism. The tail sealer 10a, 100a may be
capable of anticipating the tail 220a by counting the number of
sheets processed through the system and identify the tail 220a as
the last sheet in the count necessary to complete the log 12a,
120a.
[0130] The method 500 may further include a foam spray step 518
comprising spraying the foaming adhesive 406, where a nozzle 404
sprays the foaming adhesive 406 in a predetermined deposit pattern
at a respective spray site to form a line of adhesive 402. The
method 500 may also comprise a reattachment step 520 of reattaching
the tail 22a, 220a to the body 13a, 130a at the line of adhesive
402. The reattachment step 520 may be accomplished through a tail
winding system.
[0131] In one nonlimiting example, the predetermined deposit
pattern of the foaming adhesive 406 is generally a two-dimensional
circular or ovular pattern. In another nonlimiting example, the
predetermined deposit pattern of the foaming adhesive 406 comprises
a shape having an aspect ratio of about 1.1 or more, or about 2 or
more as measured above.
[0132] In another embodiment, the nozzle 404 is positioned at an
angle of about 45 degrees to about 135 degrees relative to a
respective spray. In another embodiment, the nozzle 404 is
positioned at an angle of about 45 degrees to about 135 degrees
relative to a table 24a, 240a, which may be provided as part of the
sealing station. In yet another embodiment, the nozzle 404 is
positioned from about 4 to about 16 inches, or from about 6 inches
to about 12 inches, or from about 6 inches to about 8 inches from
the respective spray site. In yet another embodiment, the nozzle is
positioned from about 4 to about 16 inches, or from about 6 inches
to about 12 inches, or from about 6 inches to about 8 inches from
the table 24a, 240a, which may be provided as part of the sealing
station.
[0133] In another embodiment, the foam spray step 518 includes a
plurality of nozzles 404, where the nozzles 404 may be
substantially spaced apart in a generally linear manner in the
cross machine direction. In another embodiment, the nozzles 404 may
be positioned in a pattern such that they do not form a straight
line in the cross machine direction. In one nonlimiting example,
the plurality of nozzles 404 comprises from about 9 to about 12
nozzles for about a 100-inch log 12a, 120a as measured in the cross
machine direction. In another embodiment, there is at least one
nozzle 404 per about every 11 inches of the log 12a, 120a as
measured in the cross machine direction, or per about every 8
inches of the log 12a, 120a as measured in the cross machine
direction. In one embodiment, the number of nozzles 404 is
equivalent to the anticipated number of final finished products
expected to be produced. In other words, if nine finished
consumer-sized product units were to be created from one log 12a,
120a, then nine nozzles 404 may be used. In another embodiment, the
number of nozzles 404 is greater than the number of anticipated
final finished products. In a nonlimiting example, each nozzle 404
may be positioned between about from about 4 to about 16 inches
from a respective spray site, or from about 6 inches to about 12
inches, or from about 6 inches to about 8 inches from the spray
site upon which it will deposit the foaming adhesive 406 and/or
from a table 24a, 240a which may be provided as part of the sealing
station. It is believed that in combination at a given pressure,
the nozzles 404 may create a relatively long, thin line of adhesive
402.
[0134] In an alternative embodiment, the spray system step 514 may
involve providing the spray nozzle application system 400 in an
inverted position, such that the nozzle 404 is positioned to emit
the foaming adhesive 406 in a generally upward direction. The
nozzle 404 may be provided at an angle relative to a table 240a
(which may be provided as part of the sealing station) ranging from
about 45 degrees to about 135 degrees. In another embodiment, the
nozzle 404 is positioned at an angle of about 45 degrees to about
135 degrees relative to its respective spray site. In a further
embodiment, the nozzle 404 may be positioned from about 1 to about
16 inches from the respective spray site, or from about 3 to about
4 inches from the respective spray site.
[0135] In yet another embodiment, the foam spray step 518 may
involve a plurality of inverted nozzles 404, where the nozzles 404
are substantially spaced apart in a generally linear manner in the
cross machine direction. In a nonlimiting example, the nozzles 404
may be positioned in a pattern such that they do not form a
straight line in the cross machine direction. In another
nonlimiting example, the plurality of nozzles 404 comprises from
about 12 to about 33 nozzles 404, or from about 27 to about 33
nozzles 404 for about a 100-inch log 12a, 120a as measured in the
cross machine direction. In another embodiment, there is at least
one nozzle 404 per about every 11 inches of the log 12a, 120a as
measured in the cross machine direction. In one embodiment, the
number of nozzles 404 is equivalent to anticipated number of final
finished products expected to be produced. In other words, if nine
finished consumer-sized product units were to be created from one
log 12a, 120a, then nine nozzles 404 may be used. In another
embodiment, the number of nozzles 404 is greater than the number of
anticipated final finished products. In a nonlimiting example, each
nozzle 404 may be positioned between about 1 and about 16 inches,
or from about 3 to 4 inches from the respective spray site upon
which it will deposit the foaming adhesive 406. In another
embodiment, each nozzle 404 may be positioned about 45 degrees to
about 135 degrees relative to respective spray site upon which it
may deposit the foaming adhesive 406. It is believed that in
combination at a given pressure, the nozzles 404 may create a
relatively long, thin line of adhesive 402.
[0136] In one embodiment, the method 500 is performed at a rate of
not less than 20 logs processed per minute, or at a rate between
about 30 logs processed per minute to about 60 logs processed per
minute, or from about 50 logs processed per minute to about 60 logs
processed per minute.
Product Tail Sealed with Foaming Adhesive
[0137] In one embodiment of the present disclosure, a convolutely
wound material has a tail 22a, 220a and a body 13a, 130a. The tail
22a, 220a and the body 13a, 130a may be bonded with a foaming
adhesive 406. The foaming adhesive 406 may be deposited on the tail
22a, 220a and/or the body 13a, 130a. The foaming adhesive 406 may
be emitted in a predetermined deposit pattern. The predetermined
deposit pattern may be generally two-dimensional circular or ovular
pattern. The predetermined deposit pattern may have shape with an
aspect ratio of about 1.1 or more, or about 2 or more. In another
embodiment, the tail portion 22a, 220a and body portion 13a, 130a
are bonded by a line of adhesive 402.
[0138] In one nonlimiting example, the convolutely wound web
material 600 is a fibrous structure. The material 600 may be
provided as a single-ply or multi-ply sanitary tissue product. In
another nonlimiting example, the sanitary tissue product may be a
paper towel product or a bath tissue product. The sanitary tissue
product may comprise embossing or otherwise comprise textural
elements such as peaks 602 or valleys 604.
[0139] As shown in FIGS. 12, the material 600 may have a peak 602
and a valley 604. The peak 602 and/or valley 604 may be formed at
various stages during the process of making the web material 600.
In one nonlimiting example, creping may cause such peaks 602 and/or
valleys 604 in a fibrous structure. Likewise, the peaks 602 and/or
valleys 604 may be wet-formed, (occurring while the fibers of a
fibrous structure are wet) by, for example, a belt having
particular shapes or holes. In another nonlimiting example, the
peaks 602 and/or valleys 604 of a fibrous structure may be
dry-formed (i.e., formed after the fibrous structure is dry) which
typically occurs during converting processes such as embossing. In
another nonlimiting example, the peaks 602 are formed as a
by-product of the formation of valleys 604 in the material 600.
Similarly, the valleys 604 may be formed as a by-product of the
formation of peaks 602 in the material 600.
[0140] Generally, the peaks 602 and valleys 604 extend in opposite
directions in Z-direction. In one nonlimiting example, a peak 602
extends upward in the Z-direction. The valley 604 in this case may
extend downward in the Z-direction, away from the peak 602. In one
embodiment, the peak 602 is located on the tail 22a, 220a. In
another embodiment, the peak 602 is located on the body 13a, 130a
(i.e., the non-tail portion). Alternatively, the peaks 602 may be
found on both the body 13a, 130a and the tail 22a, 220a. Likewise,
valleys 604 may be located on the tail 22a, 220a, the body 13a,
130a or both the portions of the web material 600. The peaks 602
and/or valleys 604 may be found on one or multiple sides of the
material 600. Where multiple peaks 602 are found on the material
600, said peaks 602 may comprise different heights, shapes and/or
sizes. Likewise, where multiple valleys 604 are found on a material
600, the valleys 604 may comprise different heights, shapes and/or
sizes.
[0141] In one nonlimiting example, a peak 602 and valley 604 are
adjacent and have a maximum height distance, H, of about 365
microns to about 1750 microns between them. In another nonlimiting
example, the maximum height distance, H, is from about 180 microns
to about 730 microns. The height distance is measured by measuring
distance between the furthest points on the peak 602 and the valley
604 in the Z-direction. In one nonlimiting example, as shown in
FIG. 12, the peak 602 has a maximum height, P, as measured in the
Z-direction when the material 600 having the peak 602 is laid
against a flat surface. In such instance, P is measured from the
point furthest away from the flat surface in the Z-direction. An
adjacent valley 604 may have a minimum height, M, which may be the
furthest point from P in the Z-direction within the valley 604. The
maximum height distance, H, would be the distance from P to M,
along the Z-axis.
[0142] In some instances, the peak 602 is the only available
bonding area because the valley 604 is positioned too far away from
body 13a, 130a and/or tail 22a, 220a to which it is being bonded
and/or because the pressure for compressing the body 13a, 130a
and/or tail 22a, 220a is not sufficient to allow the valley 604 to
reach the area to which it is being bonded. This is especially true
in instances where only the weight of the log 12a, 120a provides
compression pressure for pressing the tail 22a, 220a and the body
13a, 130a together. The foaming adhesive 406, for the reasons
described herein, may increase the number of adhesive contact
points on the surface of the peak 602, within a given spray site of
the web material. As a result, more efficient bonding may be
achieved as compared to non-foaming adhesive.
[0143] In one embodiment, the foaming adhesive 406 is uniformly
distributed, such that a sufficient number of bonding sites exist
on the peak 602 to ensure maximum bonding of the tail 22a, 220a to
the body 13a, 130a within about 1 minute to about 10 minutes, or
within about 1 minute to about 5 minutes, or within about 1 minute
to about 2 minutes after application.
[0144] Once cut into consumer-sized product units of 11-inch width,
the convolutely wound log 12a, 120a having its tail 22a, 220a
bonded with foaming adhesive 406 in accordance with the present
disclosure may have a peel strength ranging from about 50 g/11 inch
roll to about 400 g/11 inch roll, or from about 80g/11 inch roll to
about 300 g/11 inch roll, or from about 100g/11 inch roll to about
200 g/11 inch roll as determined by the Wet Tail Seal Strength Test
described herein. In one embodiment, rolls having a consumer-sized
product unit different than 11 inches may have a peel strength
equating to the product of the width of the consumer unit in inches
multiplied by a factor of about 4.5 g/inch to about 36.4 g/inch, or
from about 7 g/inch to about 27 g/inch, or from about 9 g/inch to
about 18 g/inch.
[0145] As shown in FIG. 13, consumer product units bonded with
foaming adhesive in accordance with the present disclosure
demonstrate higher peel strengths as determined by the Wet Strength
Tail Seal Test when compared to consumer product units bonded with
nonfoaming adhesive. In FIG. 13, the conventional line represents
the performance of typical, non-foaming water-based adhesives over
time regardless of the application mechanism.
Wet Strength Tail Seal Test Method
[0146] Tail seal wet strength of typical paper towel sample sealed
in accordance with the apparatus and method described above can be
evaluated using this method. Time should be chosen to correlate
with approximate residence time in the accumulator. 5-7 minutes may
be used but a higher number can be used if necessary. With
non-foaming adhesive and approaches, longer times will typically
increase the value of the resulting measurement as the adhesive has
the opportunity to dry and bond. Typically, an average range of
about 100 grams to about 200 grams per 11 inch roll of wet strength
tail seal as measured by this method is expected from a typical
paper towel sample sealed in accordance with the apparatus and
method described supra.
[0147] A) Start timing from the glue application to the wound
log.
[0148] B) Collect the roll once it is in consumer-sized finished
roll format.
[0149] C) Once 5-7 minutes has elapsed after glue application,
begin testing. Hold roll in a horizontal position with the tail
disposed at the 3 o'clock position, where the tail is pointed
upwards as shown in FIG. 14.
[0150] D) While holding roll in position attach binder clips having
known weights to the center of the tail. Successive clips are
attached to alternating sides of the preceding clip. Alternatively,
a single binder clip having a known weight can be used in
combination with a set of known weights which can be added to the
single clip either singly or in combination. (See FIG. 14 generally
showing the movement of the tail once a clip is attached.)
[0151] E) Once the tail fully releases from the roll, stop and
remove clips and/or weights.
[0152] F) Sum up the masses of the clips attached to the roll and
total the weight of all of the clips or alternatively, the clip and
the weights.
[0153] G) Enter the total weight in the summary sheet for
comparison of condition wet strength.
[0154] The dimensions and/or values disclosed herein are not to be
understood as being strictly limited to the exact numerical
dimension and/or values recited. Instead, unless otherwise
specified, each such dimension and/or value is intended to mean
both the recited dimension and/or value and a functionally
equivalent range surrounding that dimension and/or value. For
example, a dimension disclosed as "40 mm" is intended to mean
"about 40 mm".
[0155] Every document cited herein, including any cross referenced
or related patent or application is hereby incorporated herein by
reference in its entirety unless expressly excluded or otherwise
limited. The citation of any document is not an admission that it
is prior art with respect to any invention disclosed or claimed
herein or that it alone, or in any combination with any other
reference or references, teaches, suggests or discloses any such
invention. Further, to the extent that any meaning or definition of
a term in this document conflicts with any meaning or definition of
the same term in a document incorporated by reference, the meaning
or definition assigned to that term in this document shall
govern.
[0156] While particular embodiments of the present invention have
been illustrated and described, it would be obvious to those
skilled in the art that various other changes and modifications can
be made without departing from the spirit and scope of the
invention. It is therefore intended to cover in the appended claims
all such changes and modifications that are within the scope of
this invention.
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