Note: Descriptions are shown in the official language in which they were submitted.
1 333952
SHEET M~TERIAL FOR FORMING THE LOOP PORTION
FOR ~IOOK AND LOOP FASTENE~S
Technical Field
The present invention relates to sheet materials
adapted to be cut lnto pieces to form the loop portlons for
fasteners of the type lncluding releasably engageable hook
and loop portions, and methods for making such sheet
materlals.
~ackground of the Inventlon
Many sheet materials are known that are adapted to
be cut into pieces to form the loop portions for fasteners
of the type comprising releasably engageable hook and loop
portions. Such sheet materials typically comprise a backing
and a multlplicity of loops anchored in the backlng and
projectlng a front surface of the backinq so that they may
be releasably engaged with the hooks on the hook portion of
such a fastener, and can be made by many methods including
conventional weaving, or knitting techniques. Such a sheet
material in which the loops are stitched into the backing is
described both in U.S. Patent No. 4,609,581, and in U. S.
Patent 4,770,917. While the loop fastener
portions made from many such loop materials work well with
many dlfferent hook fastener portions, many of the processes
by which they are made are more expensive than may be
desired, particularly when the loop fastener portions are
intended for a limited amount of use, such as to attach a
disposable diaper to an infant, or to attach an abrasive
disk to a backing pad by which it is driven.
Disclosure of Invention
The present inventlon provides a sheet material
adapted to be cut into pieces to form the loop portions for
fasteners of the type comprising releasably engageable hook
and loop portions, which sheet material provides effective
loop fastener portions for such fasteners while belng very
A
-
1333952 60557-3640
inexpensive to manufacture so that they are economical to use when
the loop fastener portions are intended for a limited amount of
use, such as to releasably attach a disposable diaper or other
garment, or to attach an abrasive disk to a backing pad by which
it is driven.
According to the present invention there is provided a
method for forming a sheet material adapted to be cut into pieces
to form loop portions for fasteners of the type having releasably
engageable hook and loop portions, said method comprising:
providing a sheet comprising fibers that are generally aligned in
the same direction and a backing having front and rear major
surfaces, the fibers having a basis weight in the range of 5-200
grams per square meter measured along said front surface of the
backing to provide sufficient open area between the fibers to
afford ready engagement of the hook portion of a said fastener
with the fibers in the sheet material; forming the sheet to have
arcuate portions projecting in the same direction from spaced
anchor portions of the sheet, said arcuate portions being formed
with a height from the anchor portions of less than 0.64 cm;
bonding the spaced anchor portions of the sheet to the front
surface of the backing with the arcuate portions projecting from
said front surface.
The arcuate portions have a height from the backing of
preferably less than about 0.318 centimeters (0.125 inch). The
width of the bonding locations should be between about 0.005 and
0.075 inch, and the width of the arcuate portions of the fibers
should be between about 0.06 and 0.35 inch. The fibers in the
arcuate portions project to about the same height above the front
surface, which height is at least one third, and preferably one
C
3 1 3 3 3 9 5 2 60557-3640
half to one and one half the distance between the bonding
locations, the individual fibers are less than 15 denier in size,
and the fibers collectively have a basis weight preferably in the
range of 10 to 75 grams per square meter measured along the front
surface of the backing to provide sufficient open area between the
fibers along the arcuate portions (i.e., between about 10 to 70
percent open area) to afford ready engagement of the fibers along
the arcuate portions by the hook portion of the fastener.
Forming of the fibers is preferably done by providing
first and second generally cylindrical corrugating members each
including a plurality of uniformly spaced ridges defining its
periphery, mounting the corrugating members in axially parallel
relationship with portions of the ridges of the corrugating
members in mesh with each other, rotating at least one of the
corrugating members, feeding the sheet of fibers between the
meshed portions of the ridges of the rotating corrugating members
to generally conform the sheet of fibers to the periphery of the
first corrugating member, thereby forming the arcuate portions of
the sheet of fibers in spaces between the ridges of the first
corrugating member and the anchor portions of the sheet of fibers
along outer surfaces of the ridges of the first corrugating
member, and retaining the formed sheet of fibers along the
periphery of the first corrugating member after it has moved past
the meshing portions of the ridges. The anchor portions of the
sheet of fibers are then bonded to the front surface of the
backing while they are on the end surfaces of the ridges on the
first corrugating member, and the thus formed sheet material is
separated from the first corrugating member.
_ 3a t 3 3 3 9 5 2 60557-3640
The invention provides a sheet material adapted to be
cut into pieces to form loop portions for fasteners of the type
having releasably engageable hook and loop portions, said material
comprising: a sheet comprising fibers that are generally aligned
in the same direction and a backing having front and rear major
surfaces, the fibers having a basis weight in the range of 5-200
grams per square meter measured along said front surface of the
backing to provide sufficient open area between the fibers to
afford ready engagement of the hook portion of a said fastener
with the fibers in the sheet material; said sheet having arcuate
portions projecting in the same direction from spaced anchor
portions of the sheet, said arcuate portions being formed with a
height from the anchor portions of less than 0.64 cm, and said
spaced anchor portions of the sheet being bonded to the front
surface of the backing with the arcuate portions projecting from
said front surface.
The ridges can be elongate and generally parallel so
that the bonding locations are also elongate and generally
parallel and are continuous in one direction across the front
surface of the backing so that continuous rows of the arcuate
portions extend across the backing of the sheet material; or
alternately the ridges can be elongate, generally parallel, and in
a regular pattern of diæcontinuous lengths so that the parallel
bonding locations are also in a regular pattern of discontinuous
lengths to form a regular pattern of discontinuous rows of the
arcuate portions along the front surface of the backing. Also it
is contemplated that the ridges of the first corrugating member
can form interlocking closed patterns (e.g., circular, diamond
shaped, octagonal, etc.) to form corresponding
1 333952
--4--
patterns for the arcuate portions of the fibers along the
front surface of the backing, in which case the second
corrugating member will be formed with post like ridges to
press the fibers into the centers of the closed patterns.
Elongate ridges on the corrugating members can be
oriented at any angle in the range of 0 to 90 degrees with
respect to their axes so that the rows of arcuate portions,
whether continuous or discontinuous, can be oriented along
or transverse to the sheet of fibers fed between the
corrugating member or at any angle therebetween.
The backing could be a woven, knitted, random
woven, nonwoven or other layer of intertwined fibers, but
preferably is a continuous polymeric film in the range of
about 0.0025 to 0.013 centimeters (0.001 to 0.005 inch)
thick which is generally less expensive than a backing of
entwined fibers and allows the backing to be printed by
conventional methods along one of its surfaces with graphics
(such as advertising, instructions or locating marks) which
will be visible through the loop portions of the fibers due
to their large percentage of open area. The film may be a
single layer of a polymeric material such as polypropylene,
polyester, or polyamide; or may have a plurality of layers
such as a central layer of a relatively high strength
material such as polyester, a layer defining the first
surface of a material more easily bonded to the fiber such
as ethylene vinyl acetate or polyethylene, and a layer
defining its second surface adapted to adhere the backing to
a substrate such as polyethylene or a bonding layer of
room-temperature non-tacky thermoplastic material adapted to
adhere a fastener portion to a polyolefin layer (such as may
be found on a disposable diaper) that can be bonded to the
polyolefin layer under heat and pressure that leaves the
polyolefin layer substantially undeformed and will hold the
fastener portion to the polyolefin layer with greater force
than that which is required to separate an engaged fastener,
which bonding layer of room-temperature non-tacky
thermoplastic material is described in U.S. Patent
1 3339~
No. 4,973,326, and can
include from about 40% to about 100% of a thermoplastic
material having a softening polnt of generally below 120
degrees Centiqrade and preeerably below 100 degrees
5 Centigrade, and from about 60% to about 0% of a tacklfylng
resin that has a softening point below about 105 deqrees
Centlgrade and preferably below 95 degrees Centigrade.
Suitable thermoplastic materials include ethylene and
propylene based copolymers such as ethylene/vinyl acetate
copolymers, ethylene/acryllc acld copolymers, and
ethylene/methacryllc acld copolymers. Preferred
thermoplastic materials include ethylene/vinyl acetate
copolymers, especially those with a melt flow index from
about 40 to about 2500, and preferably with a melt flow
index between about 50 and abou' 1000. Such materlals are
available commercially as Elvax*40W, Elvax 150, Elvax 210W,
Elvax 220W, Elvax 310, Elvax 410, and Elvax 4980W from E. I.
DuPont de Nemours and Co. of Wllmington, Delawaret Escorene*
UL7710 and Escorene UL7720 from Exxon Chemlcal Co., Houston,
Texas; and Ultrathene*639-35 and Ultrathene 649-04,
available from USI Chemical Co. of Cincinnatl, Ohio.
Suitable tackifying resins are preferably solid or
semisolid, however liquid tackifylng resins can also be
used. The tackifying resin, when used, should be compatlble
with the thermoplastic material and may include rosin
esters, rosin aclds, and derlvatlves of these; hydrogenated
rosin esters and rosin acids and derivatives of these;
aliphatlc hydrocarbon resins; mixed aliphatic/aromatlc
hydrocarbon resins, polyterpene resins; resins made from the
polymerlzation and hydrogenatlon of a dicyclopentadlene feed
stream; polyterpene reslns and aromatic-modlfied polyterpene
resins; resins made from the polymerization and
hydrogenation of a C9 hydrocarbon stream; and resins made
from the polymerlzatlon and hydrogenatlon Oe a mlxture of
alphamethyl styrene, styrene, and vlnyl toluene. Preferred
tackifylng resins include allphatic hydrocarbon reslns such
as Escorez~15a0 and Escorez 1310, available from Exxon
.* Trademarks
A
1 333952
--6--
Chemlcal of Houston, Texas; Hercotac*95, avallable from
Hercules Chemical Co. of Wilmington, Delaware; and Wingtack*
Plus and Wingtack 95, avallable from the Goodyear Tire and
Rubber Company of Akron, Ohio. Additional preferred solid
tackifying resins include the aromatic-modified polyterpene
res~ns such as Wingtack 86, available from Goodyear; 20natac *
105, available from Arizona Chemical Co. of Panama Clty,
Flor1da; and Res D-20~3, available from Hercules1 res1ns
made from the polymerlzatlon and hydrogenatlon of a
dicyclopentadiene feed stream such as Escorez 5380,
available from Exxon; resins made from the polymerization
and hydrogenation of a C9 hydrocarbon stream such as Arkon*
P-90, available from Arakawa Chemical Co. USA of Chicago,
Illinois; and resins made from the polymerizatlon and
hydrogenation of mixtures of alphamethyl styrene, styrene,
and vinyl toluene such as Regalrez*1065, Regalrez 1078, and
Regalrez 1094, available from Hercules. Conventional
additives for hot-melt adhesives may also be incorporated
into the bonding layer, including, but not limited to,
waxes, fillers, oils, pigments, antioxidants, ultraviolet
light stabilizers, and heat stabilizers.
The individual fibers may be of many polymerlc
materials such as polypropylene, polyethylene, polyester, or
polyamlde, or comblnatlons of such materlals such as a core
25 of polyester and a sheath of polypropylene whlch provldes
relatlvely high strength due to its core material and ls
easily bonded due to its sheath material. Fibers of one
material or fibers of different materials or material
combinations may be used in the same sheet material.
The sheet of fibers may be fed between the meshed
ridges of the corrugating members in the form of a non woven
or random woven sheet or web in which the fibers may or may
not be bonded together. In such a sheet the fibers may be
disposed in various directlons with respect to the directlon
the sheet of fibers is fed between the corrugating members
so that in the resultant sheet material the fibers are
disposed in various directions with respect to the spaced
* ~rademarks
7 1 333~52
bonding locations. In such a sheet to be fed between
corrugating members with spaced parallel ridges, preferably
a majority of the fibers (e.g., over 90 percent) project in
one direction along the web and the web is fed between the
5 corrugating members with that direction at about a right
angles to the ridges on the corrugating members so that in
the resultant sheet material a majority of the fibers
project generally at about right angles to the parallel
bonding locations.
Alternatively, the fibers may be provided in the
form of yarns in the range of 50 to 300 denier, the yarns
distributed to provide a sheet of generally uniformly
distributed fibers by passing them through a comb, and the
sheet of fibers fed between corrugating members having
elongate parallel ridges oriented in the range of 0 to 45
degrees with respect to their axes in a direction
perpendicular to their axes, which results in a sheet
material in which the fibers all extend in directions at
about the same angles with respect to the parallel bonding
locations.
When the contacting portions of the backing and
the fibers are of the same thermoplastic material, bonding
of the fibers to the backing can be done by sonic welding or
other means of applying heat and pressure to fuse the fibers
to the backing at the bonding location. Alternatively, or
when the contacting portions of the backing and the fibers
are of different materials, the fibers may be adhesively
bonded to the backing such as by softening a thermoplastic
adhesive layer of the backing by sonic energy or other means
of applying heat and pressure to adhere the fibers to the
backing at the bonding locations.
Brief Description of Drawing
The present invention will be further described
with reference to the accompanying drawing wherein like
reference numerals refer to like parts in the several views,
and wherein:
-8- l 3 33qS2
Figure 1 is a perspective view of a sheet material
according to the present invention;
Figure 2 is a much enlarged top plan view of the
sheet material of Figure 1;
Figure 3 is a much enlarged end view of the sheet
material of Figure l;
Figure 4 is a schematic view illustrating an
apparatus and a method according to the present invention
for making the sheet material of Figure l;
Figures 5 and 6 are top and side views
respectively illustrating a first alternate embodiment of
the apparatus of Figure 4;
Figures 7 and 8 are top and side views
respectively illustrating a second alternate embodiment of
the apparatus of Figure 4; and
Figures 9 and 10 are top and side views
respectively of an alternate embodiment of a sheet material
according to the present invention made by the apparatus of
Figures 7 and 8.
Detailed Description
Referring now to the drawing, there is shown in
Figures 1, 2 and 3 a sheet material according to the present
invention, generally designated by the reference numeral 10,
which sheet material 10 is adapted to be cut into pieces to
form the loop portions for fasteners of the type having
releasably engageable hook and loop portions.
Generally the sheet material 10 comprises a
transparent thermoplastic film backing 12 (e.g., of
polypropylene or polyester) in the range of about 0.0025 to
0.013 centimeters (0.001 to 0.005 inch) thick having front
and rear major surfaces 13 and 14, and a multiplicity of
fibers 16 having portions bonded (i.e., by being fused or
adhesively attached) to the front surface 13 of the backing
12 at spaced elongate generally parallel bonding locations
18 that are continuous in one direction along the front
9 1 333~52
surface 13 to form arcuate portions 20 of the fibers 16
projecting from the front surface 13 of the backing 12
between the bonding locations 18 in continuous rows
transversely across the sheet material 10. The arcuate
5 portions 20 of the fibers 16 have a generally uniform height
from the backing 12 of less than about 0.64 centimeters
(0.250 inch) and preferably less than about 0.318
centimeters (0.125 inch), the height of the fibers 16 is at
least one third, and preferably one half to one and one half
times the distance between the bonding locations 18, the
individual fibers 16 are less than 15 denier (preferably in
the range of 1 to 10 denier) in size, and the fibers 16
without the backing 12 have a basis weight in the range of 5
to 200 grams per square meter (and preferably in the range
of 10 to 75 grams per square meter) measured along the first
surface 13 to provide sufficient open area between the
fibers 16 along the arcuate portions 20 (i.e., between about
10 and 70 percent open area) to afford ready engagement of
the fibers 16 along the arcuate portions 20 by the hook
portion of the fastener.
The fibers 16 can be disposed in various
directions with respect to the parallel bonding locations 18
and may or may not be bonded together at crossover points in
the arcuate portions 20; can be disposed in various
directions with respect to the parallel bonding locations 18
with the majority of the fibers 16 (i.e., over 90 percent)
extending in directions at about a right angle to the
bonding locations 18; or all of the fibers 16 can extend in
directions generally at right angles to the spaced generally
parallel bonding locations 18.
The backing 12 may have printing 22 along either
one or both of its surfaces 13 or 14 applied by conventional
printing techniques, which printing 22 is readily visible
through the arcuate portions 20 of the fibers 16.
Figure 4 schematically illustrates a method
according to the present invention for forming the sheet
material 10 which generally comprises forming the fibers 16
1 333~52
--10--
into a sheet of fibers having arcuate portions projecting in
the same direction from spaced generally parallel anchor
portions 24 of the sheet, and bonding the spaced generally
parallel anchor portions 24 of the sheet of fibers 16 to the
front surface 13 of the backing 12 with the arcuate portions
of the fibers 16 projecting from the front surface 13 of the
backing 12. This method is preferably performed by
providing first and second heated (e.g., 280 degrees F)
corrugating members or rollers 26 and 27 each having an axis
and including a plurality of circumferentially spaced
generally axially extending ridges 28 around and defining
its periphery, with the ridges 28 having outer surfaces and
defining spaces between the ridges 28 adapted to receive
portions of the ridges 28 of the other corrugating member in
meshing relationship with the sheet of fibers between the
meshed ridges 28 and to afford rolling engagement between
the ridges 28 and spaces of the corrugating members in the
manner of gear teeth. The corrugating members 26 and 27 are
mounted in axially parallel relationship with portions of
the ridges 28 of the corrugating members 26 and 27 meshing
generally in the manner of gear teeth; at least one of the
corrugating members 26 or 27 is rotated; and the sheet of
fibers is fed between the meshed portions of the ridges 28
of the corrugating members 26 and 27 to generally conform
the sheet of fibers to the periphery of the first
corrugating member 26 and form the arcuate portions of the
fibers 16 in the spaces between the ridges 28 of the first
corrugating member 26 and the generally parallel anchor
portions 24 of the sheet of fibers along the outer surfaces
of the ridges 28 on the first corrugating member 26. The
formed sheet of fibers is retained along the periphery of
the first corrugating member 26 after it has moved past the
meshed portions of the ridges 28; the backing 12 is bonded
to the parallel anchor portions 24 of the sheet of fibers on
the end surfaces of the ridges 28 on the first corrugating
member 26 as by the action of a sonic welder 30 or by other
sources of heat and pressure such as heat from within the
-11- 1 333~52
first corrugating member 26; and the bonded backing 12 and
fibers 16 or sheet material 10 is separated from the first
corrugating member 26.
The sheet of fibers fed between the meshed
5 portions of the ridges 28 of the corrugating members 26 and
27 can be in the form of a non woven web or sheet, or, as
illustrated in Figure 4, in the form of yarns 33 distributed
to provide a sheet of uniformly distributed fibers by
passing the yarns 33 through a comb 34 and fed between the
10 meshed portion of the ridges 28 of the corrugating members
26 and 27 with all of the fibers 16 extending generally
perpendicular to the axes of the corrugating members 26 and
27. Corrugating members 26 and 27 adapted to have such a
sheet of fibers 32 fed into them can have their ridges 28
oriented generally in the range of 0 to 45 degrees with
respect to their axes, but preferably have their ridges 28
oriented at about 5 degrees with respect to their axes so
that the sonic welder 30 will always be adjacent and heating
the parallel portions 29 of the sheet of fibers along a
portion of at least one of the ridges 28 to help even out
the energy output of the sonic welder 30 and so that the
fibers 16 in the sheet material 10 all extend in directions
at about right angles (i.e., 85 degrees) to the parallel
bonding locations 18.
Additionally, the method can further include
printing the backing along one of its surfaces prior to the
bonding step, as along its rear surface 14 with a printer
36, which may preferably be done at a location remote from
the corrugating members 26 and 27.
Figures 5 and 6 schematically illustrate a first
alternate way to perform the method according to the present
invention for forming a sheet material 40 according to the
present invention, which method generally comprises forming
fibers 38 into a sheet having arcuate portions 41 projecting
in the same direction from spaced generally parallel anchor
portions of the sheet, and bonding the spaced anchor
portions of the sheet of fibers with the fibers along a
1 333952
-12-
front surface of a backing 43 with the arcuate portions 41
projecting from the front surface of the backing 43. As
illustrated, the method can be performed by providing first
and second cylindrical heated corrugating members or rollers
44 and 45 each having an axis and including a plurality of
generally annular, circumferentially extending, axially
spaced ridges 46 around and defininq its periphery, with the
ridges 46 having outer surfaces and defining spaces between
the ridges 46 adapted to receive portions of the ridges 46
of the other corrugating member 44 or 45 in meshing
relationship with the sheet of fibers between the meshed
portions of the ridges 46. The corrugating members 44 and
45 are mounted in axially parallel relationship to mesh
portions of the ridges 46 of the corrugating members 44 and
45; at least one of the corrugating members 44 or 45 is
rotated; and the sheet of fibers is fed between the meshed
portions of the ridges 46 of the corrugating members 44 and
45 to generally conform the sheet of fibers to the periphery
of the first corrugating member 44 and form the arcuate
portions 41 of the fibers in the spaces between the ridges
46 of the first corrugating member 44 and the generally
parallel anchor portions of the fibers along the outer
surfaces of the ridges 46. The formed sheet of fibers is
retained along the periphery of the first corrugating member
44 after separation of the ridges 46; the backing 43 is
bonded to the parallel anchor portions 92 of the sheet of
fibers on the end surfaces of the ridges 46 of the first
corrugating member 44 at spaced elongate generally parallel
bonding locations corresponding to the end surfaces of the
ridges 46 on the first corrugating member 44 as by the
action of a sonic welder 50 or by other sources of heat and
pressure such as heat from within the first corrugating
member 44; and the thus completed sheet material 40 is
separated from the first corrugating member 44.
The fibers 38 fed between the meshed ridges 46 of
the corrugating members 44 and 45 can be in the form of a
non woven web formed by adhering the fibers together, or
-13- ~ 333952
another sheet formed of the fibers that has sufficient
internal strength so that the sheet of fibers will corrugate
longitudinally to conform to the ridges 46 as it is pulled
into the nip between the meshing ridges 46 of the
5 corrugating members 44 and 45. Preferably a majority of the
fibers 38 in such a non woven sheet of fibers are oriented
transversely of the direction the sheet of fibers is fed
between the corrugating members 44 and 45 so that a majority
of the fibers in the resultant sheet material 40 extend in
10 directions at about right angles to the parallel bonding
locations. Additionally, the method can further include
printing the backing along one of its surfaces prior to the
bonding step (not shown).
Like the sheet material 10, the sheet material 40
15 made by the method illustrated in Figures 5 and 6 comprises
the backing 43 (which can be a thermoplastic film), and the
fibers 38 which are bonded (i.e., by being fused or
adhesively attached) to the backing 43 at the spaced
elongate generally parallel bonding locations along the
20 front surface, which bonding locations are continuous in one
direction across the sheet material 40 to form arcuate
portions 54 of the fibers 38 projecting from the front
surface of the backing 43 between the bonding locations in
continuous rows, except that the continuous rows of arcuate
25 portions 54 in the sheet material 40 extend longitudinally
along the sheet material 40 instead of transversely across
the sheet material as in the case of the sheet material 10.
Figure 7 and 8 schematically illustrate a second
alternate way to perform the method according to the present
30 invention for forming a sheet material 60 illustrated in
Figures 9 and 10, which method illustrated in Figures 7 and
8 generally comprises forming fibers 59 into a sheet having
arcuate portions 61 projecting in the same direction from
spaced generally parallel anchor portions 62 of the sheet of
35 fibers, and bonding the spaced generally parallel anchor
portions 62 of the sheet of fibers to a front surface 58 of
a backing 63 to form bonding locations 68 with the arcuate
portions 61 projecting from the front surface 58. As
-14- 1 33 3q52
illustrated, the method can be performed by providing first
and second cylindrical heated corrugating members or rollers
64 and 65 each having an axis and including a plurality of
circumferentially spaced generally axially extending
5 discontinuous ridges 66 around and defining its periphery,
with the ridges 66 on each corrugating member 64 or 65
having outer surfaces and defining spaces between the ridges
66 adapted to receive a portion of the ridges 66 of the
other corrugating member 64 or 65 in meshing relationship in
10 the manner of a pair of gears with the sheet of fibers S9
between the meshed portions of the ridges 66. The
corrugating members 64 and 65 are mounted in axially
parallel relationship to mesh portions of the ridges 66 of
the corrugating members 64 and 65 in the manner of gear
15 teeth; at least one of the corrugating members 64 or 65 is
rotated; and the sheet of fibers 59 is fed between the
meshed portions of the ridges 66 of the corrugating members
64 and 65 to generally conform the sheet of fibers to the
periphery of the first corrugating member 64 and form the
20 arcuate portions 61 of the fibers in the spaces between the
ridges 66 of the first corrugating member 64 and the
generally parallel anchor portions 62 of the sheet of fibers
along the outer surfaces of the ridges 66. The formed sheet
of fibers is retained along the periphery of the first
25 corrugating member 64 after it moves past the meshing
portions of the ridges 66; the backing 63 is bonded to the
parallel anchor portions 62 of the sheet of fibers on the
end surfaces of ridges 66 of the first corrugating member 64
as by the action of a sonic welder 67 or by other sources of
30 heat and pressure such as heat from within the first
corrugating member 64; and the thus completed sheet material
60 is separated from the first corrugating member 64.
The fibers 59 can be fed between the meshed
portions of the ridges 66 of the corrugating members 64 and
35 65 in the form of yarns 70 distributed to provide a sheet of
uniformly distributed fibers 59 by passing the yarns 70
through a comb 72 and fed between the meshed ridges 66 of
-15- 1 333~52
the corrugating members 64 and 65 with all of the fibers
extending generally perpendicular to the axes of the
corrugating members 64 and 65, in which case the corrugating
members 64 and 65 can have their ridges 66 oriented in the
5 range of 0 to 45 degrees with respect to their axes, but
preferably have their ridges 66 oriented at about 5 degrees
with respect to their axes so that the sonic welder 67 will
always be adjacent and heating the parallel anchor portions
62 of fibers along a portion of one of the ridges 66 to~help
10 even out the energy output of the welder 67 and so that in
the sheet material 60 the fibers all extend in directions at
about right angles (i.e., 85 degrees) to parallel bonding
locations 68 between the fibers 59 and the backing 63.
Alternatively, the fibers 59 fed between the meshed ridges
15 66 of the corrugating members 64 and 65 can be in the form
of a non woven or random woven web formed by adhering fibers
together or laying unattached fibers together. In that case
the ridges 66 may be oriented at any angle with respect to
the axes of the corrugating members 64 and 65, and
20 preferably a majority of the fibers in such a sheet of
fibers are oriented at right angles to the ridges 66 so that
a majority of the fibers in the resultant sheet material 60
extend in directions at about right angles to the parallel
bonding locations 68. Additionally, the method can further
25 include printing the backing along one of its surfaces prior
to the bonding step (not shown). Additionally, the method
can further include printing the backing along one of its
surfaces prior to the bonding step (not shown).
Like the sheet materials 10 and 40, the sheet
30 material 60 made by the method illustrated in Figures 7 and
8 and illustrated in Figures 9 and 10 Comprise the backing
63 (which can be a thermoplastic film), and the fibers 59
which are bonded (i.e., by being fused or adhesively
attached) to the front surface 58 of the backing 63 at the
35 spaced elongate generally parallel bonding locations 68 to
form rows of the arcuate portions 61 of the fibers 59
projecting from the front surface 58 of the backing 63
1 333952
-16-
between the bonding locations 68, except that the rows of
arcuate portions 69 are discontinuous and form a regular
pattern along the sheet material 60 instead of being
continuous in one direction across the sheet material as in
5 the case of the sheet materials 10 and 40.
The following are illustrative examples of sheet
materials according to the present invention formed by the
method described above.
10 Example 1
A sheet material according to the present
invention was made using 2.4 denier individual polypropylene
fibers commercially available as style 80/2 yarn, 70/34
denier Solution-dyed Stuffer Crimped Olefin Fibers from
15 Roselon Industries of New York, N.Y., and a backing of
conventional polypropylene film (some of which was printed
on one surface) with a thickness of about 50 microns. The
yarns of polypropylene filaments were passed through a comb
having 6.3 teeth per centimeter (16 teeth per inch) to form
20 a sheet of uniformly distributed filaments that was then fed
between two corrugating rollers with meshing ridges of the
type described above with reference to Figure 4, carried
along the periphery of a first one of the corrugating
rollers, and had the parallel anchor portions of the sheet
25 of fibers carried along the outer surfaces of the ridges
ultrasonically fused to the backing in the manner described
above. The ridges and spaces between the ridges were shaped
to cause a feed rate of the sheet of fibers about twice that
of the film backing and to result in sheet material having
30 parallel elongate bonding locations generally perpendicular
to all of the fibers, having a transverse width of about
0.076 centimeter and spaced every 0.381 centimeter along the
sheet material; and having projecting arcuate portions of
the fibers roughly semicircular in shape with heights of
about 0.381 centimeter (0.15 inch) between the parallel
bonding locations. The printing on the backing could be
easily seen through the arcuate portions of the fibers. The
1 333952
sheet material was tested for Dynamic Shear and T-Peel in
accordance with the test methods described at the end of
this specification when engaged with a 2 inch by 1 inch
sized piece of both the mushroom headed hook material sold
under the trade designation SJ-3492, "SCOTCHMATE" Fastener,
by Minnesota Mining and Manufacturing Co., St. Paul, Minn.,
and a hook material (called "Extruded Hook Materlal" herein)
made
by
extruding a thermoplastic resln through a die shaped to form
a base layer and spaced rldges pro~ectlnq above an upper
surface of the base layer that have the cross sectlonal
shape of the hook portions to be formed, transversely
cutting the ridges at spaced locations along their length to
form discrete portions of the ridges, and stretching the
backing layer to separate those portions of the rldges which
are then the spaced hook members, which hook members each
comprise a stem portion attached at one end to the backing,
and a head portion at the end of the stem portion opposite
the backlng, the hook members each have a helght dimension
from the upper surface of the backing of 0.102 centlmeter
(0.04 inch); the stem and head portions each have generally
the same thickness dimension of about 0.025 centimeter (0.0l
inch) in a first direction parallel to the surfaces of the
backing; the stem portions each have a width dimenslon of
about 0.027 centimeter (0.01 inch) in a second direction
generally at a right angle to the first direction and
parallel to the surfaces of the backing, and the head
portions each have a width dimension in the second direction
that is about 0.066 centimeter (0.026 inch) greater than the
width dimension of the stem portlon and a total width of
about 0.066 centimeter (0.026 inch); the fastener portion
includes about 70 hook members per square centimeter (450
hook members per square inch); while the total cross
sectional area occupied by the head portions in a plane
parallel to the upper surface is about 11.7 percent of the
area of the upper surface.
* Trademark
- -18- l 3 3 3 9 5 2
The average results obtained are tabulated in
table 1 below.
Example 2
A sheet material according to the present
invention was made as described in Example 1 except that the
individual fibers used were 6.2 denier polypropylene fibers
commercially available in the form of 420/68 yarn from
Phillips Fibers Incorporated, Greenville, SC. The printing
on the backing of the sheet material could be easily seen
through the arcuate portions of the fibers. The sheet
material was tested as in Example 1, and the average results
obtained are tabulated in table 1 below.
Example 3
A sheet material according to the present
invention was made as described in Example 1 except that the
individual fibers used were 6.2 denier polypropylene fibers
commercially available as 420/68 yarn from Phillips Fibers
Incorporated, Greenville, SC., and the ridges and spaces
between the ridges of the corrugating rollers were shaped to
cause projecting arcuate portions of the fibers roughly
semicircular in shape with heights of about 0.318 centimeter
(0.125 inch) between the parallel bonding locations. It was
noted that the printing on the backing could be easily seen
through the arcuate portions of the fibers. The sheet
material was tested as in Example 1, and the average results
obtained are tabulated in table 1 below.
Example 4
A sheet material according to the present
invention was made as described in Example 1 except that no
comb was used and the individual fibers used were 11 denier
polypropylene sheath and polyester core fibers commercially
available from BASF Corporation, Williamsburg VA, a nonwoven
web having a basis weight of approximately 35 grams per
square meter was formed from the fibers after orienting the
- 1 333952
1 9
majority or about 90 percent of the fibers in one direction
by standard carding techniques and the nonwoven web was fed
into the rollers with said one direction perpendicular to
the axes of the rollers, and the ridges and spaces between
the ridges of the corrugating rollers were shaped to cause
projecting arcuate portions of the fibers roughly
semicircular in shape with heights of about 0.318 centimeter
(0.125 inch) between the parallel bonding locations. The
sheet material was~tésted as in Example 1, and the average
results obtained are tabulated in table 1 below.
TABLE 1
Extruded Hook Material Scothmate Hooks
Dynamic Shear T-Peel Dynamic Shear T-Peel
(pounds) (pounds) (pounds) (pounds)
Example
1 15.0 * 1.5 9.8 0.6
2 10.9 * 0.9 9.9 0.4
3 10.9 * 0.8 7.5 0.3
4 9.8 * 1.5 6.2 0.6
* backings elongated and hooks did not release
from loops
Comparative Examples 5-19
A series of sheet materials according to the present
invention, Examples 5-13, were made as described in Example
4 except that the individual fibers used were a mixture of
65 percent of the 11 denier polypropylene sheath and
polyester core fibers commercially available from BASF
Corporation, Williamsburg VA, and 35 percent 6 denier
polypropylene fibers commercially available from Hercules
Inc., Wilmington, Del. The nonwoven webs made from those
1 333i,~f~
-20-
fibers were varied in their densities to produce a series of
basis weights for the fibers (not including the backing)
measured along the first surfaces of the backing of the
sheet material.
Also, sheet materials according to the present invention,
Examples 14-19, were made as described in Example 1 except
that the individual fibers used were 2.9 denier
polypropylene fibers commercially available in the form of
100/34 yarn from Amoco Fabrics and Fibers Company, Atlanta,
10 GA, the backing of the sheet material was not printed, and
the fiber contents of the sheet materials were varied in
their densities or basis weights by varrying the nuber of
yarns per width to produce a series of basis weights for the
fibers (not including the backing) measured along the first
15 surfaces of the backing of the sheet material.
All of the sheet materials thus made were tested for T-Peel
in accordance with the test method attached at the end of
this specification when engaged with a 2 inch by 1 inch
sized piece of both the mushroom headed hook material sold
20 under the trade designation SJ-3492, "SCOTCHMATE" Fastener,
by Minnesota Mining and Manufacturing Co., St. Paul, Minn.,
and the average results obtained are tabulated in table 2
below.
Additionally, the arcuate portions of the fibers on certain
25 of the sheet materials were measured on an IBAS image
analyzer using routine #455, with 6 fields 2.2 square
centimeters in size being measured for each sheet material,
and the average results for percent open area obtained are
tabulated in table 2 below.
-21- 1 33~9~2
TABLE 2
Fiber
Basis Wt. Open
Fiber Source (gms/sq. T-Peel Area
Example (see above) meter) (pounds) (%)
Non Woven Mixture 20 64
6 Non Woven Mixture 35 176 48.5
7 Non Woven rlixture 50 336
8 Non Woven Mixture 63 314 41.9
9 Non Woven Mixture 77 516
Non Woven Mixture 78 324
11 Non Woven Mixture 80 240
12 Non Woven Mixture 85 210
13 Non Woven Mixture 139 118 9.3
14 Yarn 6.5 80
Yarn 12 168
16 Yarn 25 160
17 Yarn 50 282
18 Yarn 120 284
19 Yarn 140 82
Example 20
A sheet material according to the present
30 invention was made
to demonstrate adhesively bonding fibers to a backing. The
sheet material was made as described in Example 1 except
that no comb was used; the fibers used were 9 denier
polypropylene st.aple fibers commercially available from
35 Hercules Incorporated, Norcross, GA; the backing used was
0.0056 centimete~ (0.0022 inch) polypropylene film extrusion
coated with about 0.005 centimeter (0.002 inch) of low melt
1 333952
-22-
temperature tackified ethylene vinyl acetate hot melt
adhesive; a nonwoven web having a basis weight of
approximately 17 grams per square meter was formed from the
fibers by heat fusing them together after orienting the
5 majority or about 90 percent of the fibers in one direction
and the nonwoven web was fed into the corrugating rollers
with said one direction perpendicular to the axes of the
corrugating rollers; the backing was adhesively bonded to
the parallel portions of the fibers carried along the outer
10 surfaces of the ridges by heating the first roller to soften
the ethylene vinyl acetate coating rather than by sonic
welding; and the ridges and spaces between the ridges on the
corrugating rollers were shaped to cause projecting arcuate
portions of the fibers roughly semicircular in shape with
15 radii of about 0.318 centimeter (0.125 inch) between the
parallel bonding locations. The sheet material was not
tested, although it appeared to work as well as the better
examples described above.
20 Example 21
A sheet material according to the present
invention was made generally as described in Example 1
except that the fibers used were those commercially
available from Hercules as lOd T-181 fibers. A very open
25 non woven web having a basis weight in the range of about 20
to 25 grams per square meter was formed from the fibers by
randomly orienting the fibers and point bonding about 4 to
6% of the fibers together at their cross over points, and
that web was then fed between the two corrugating rollers
30 with meshing ridges of the type described above with
reference to Figure 4, carried along the periphery of a
first one of the corrugating rollers, and had the parallel
anchor portions of the web or sheet of fibers carried along
the outer surfaces of the ridges ultrasonically fused to the
backing in the manner described above.
1 333~52
-23-
Example 22
A sheet material according to the present
invention was made generally as described in Example 1
except that the backing of the sheet material was a
5 bilayered film including a layer of low melt tackified ethyl
vinyl acetate with a softening point of 150 degrees
Fahrenheit and a layer of polypropylene similar to the film
of example one; and that a rubber roll was used in place of
the sonic horns to achieve adhesive bonding of the fibers to
10 the layer of ethyl vinyl acetate through the application of
heat and pressure.
Example 23
A sheet material according to the present
15 invention was made generally as described in Example 1
except that no comb was used and the multiplicity of fibers
used to form the sheet of fibers were those commercially
available from Hercules as 9d T-101 fibers. The fibers were
used in an amount to provide a basis weight of 45 grams per
square meter for the sheet of fibers, and the orientation of
the fibers in the sheet was estimated to be in a ratio of
about seven in the longitudinal direction to one in the
cross direction.
-24- l 333952
PEEL TEST
EQUIPMENT:
5 1. Tensile Tester Instron Model TM equipped with "CT"
load cell or tensile tester (Thwing Albert) Model
"Intelect".
2. 11 + 1/4 lb. (5.0 + 0.1 kg) roller with a 4 1/8"
(104.8 mm) diameter and a 3" (76 mm) length capable of
being rolled by hand or mechanically.
3. Hook and loop material in the width supplied, not to
exceed 2" (51 mm) width; materials greater than 2" (51
mm) in width should be slit to a 2" (51 mm) width.
4. Scissors
SAMPLE:
A strip of the appropriate hook or mushroom material at
least 7" (178 mm) long by width and an equal length of the
loop to which it will be mated. If the samples are removed
20 from a roll of material remove the outer lap of material
before selecting the required number of strips. On each
strip the end closest to the center of the roll must be
marked. These markings are used to mark the directionality
of the specimens.
INSTRUMENT PREPARATION:
1. See TM App. #3 for load cell calibration procedure
using "CT" load cell.
2. See Instron for the following conditions:
a. Crosshead speed: 12 in./min. (305 mm/min.)
b. Chart speed: 5-12 in./min. (127-305 mm/min.)
c. Gauge length: 3 + 1/8" (76.2 + 3.2 mm)
d. Load range: 10 lbs. (44.5 N) full scale load
e. Peel distance: 3" (76.2 mm)
CONDITIONS:
All hook and loop samples should be laid functional side up
-25- l 333952
and conditioned for at least 24 hours at 70 + 2F
(21.1 + 1.1C) and 65 + 2% relative humidity prior to
testing specimens.
PROCEDURE:
l. Carefully align and superimpose the hook strip over
the loop strip so that the hook strip covers the loop
strip, and the marked ends are matched. Join the
strips together lightly using finger pressure.
2. Using the roller, engage the entire length of the
mated strips by rolling over surface at a rate of
approximately 12" (305 mm)/min. making one pass in
each direction 3 times. Then hand separate at least
2-1/2" (63.5 mm) but no more than 3" (76.2 mm) of the
combined specimens.
3. Place the free ends of the specimen to be tested in
the Instron with the hook strip end in the upper clamp
and the free end of the loop strip in the lower clamp.
The peel line should be centered.
4. ~urn on the pen and chart and start the peel test.
5. Ignore the first peak and from the remaining peaks,
select the five highest peaks and calculate an average
for the peel force value.
60 A total of 6 separate specimen combinations will be
tested, 3 with marked ends together and 3 with marked
ends opposite.
3 each: hook x
loop X
hook X
loop X
7. The average value of the 6 peel tests should be
recorded in pounds per inch width to the nearest tenth
of a pound. This value characterizes one sample.5
-26- 1 333952
SHEAR STRENGTH TEST
5 EQUIPMENT:
1. Tensile Tester Instron Model TM equipped with "CT"
load cell or tensile tester, (Thwing Albert) Model
"Intelect".
2. 11 + 1/4 lb. (5.0 + 0.1 kg) roller with a 4-1/8" (105
mm) diameter and a 3" (76 mm) length capable of being
rolled by hand or mechanically.
3. Hook and loop material in the width supplied, not to
exceed 2" (51 mm) width. Materials greater greater
than 2" (51 mm) in width should be slit to a 2" (51
mm) width.
4. Scissors.
5. Bell jar with a super saturated solution of magnesium
acetate and water in bottom to keep R.H. at 65% at
70F (21C).
SAMPLE:
A strip of the appropriate hook or mushroom material at
least 4" (102 mm) long by width and an equal length of the
loop to which it will be mated. If the samples are removed
25 from a roll of material remove the outer lap of material
before selecting the required number of strips.
INSTRUMENT PREPARATION:
1. Calibrate the load cell.
30 2. Set the Instron for the following conditions:
. Crosshead speed: 12" (305 mm)/min.
b. Chart speed: 5-12" (127-305 mm)/min.
c. Guage length: 3 + 1/8" (76 + 3 mm)
d. Load range: 100 lbs. (445 N) full scale load5
-27- l 3 3 3 9 52
CONDITIONING:
All hook and loop samples should be laid functional side up
and conditioned for at least 24 hours at 70 t 2F (21 +
1C) and 65 + 2% relative humidity prior to testing.
PROCEDURE:
1. Place the 4" (102 mm) long strip of loop material,
loop side up, on a flat rigid surface. Fasten end of
the loop to the surface with pressure sensitive tape
to prevent movement.
2. Carefully align and superimpose 2 + 1/16" (50 + 2 mm)
of the hook strip over the loop strip. Join the
strips together lightly using finger pressure.
3. Using the roller, engage the mated strips by rolling
over the surface at a rate of approximately 12" per
minute (305 mm/min.) making one pass in each direction
3 times.
4. Place the free ends of the specimen to be tested in
the instron with the hook strip end in the upper clamp
and the free end of the loop strip in the lower clamp.
The shear line should be centered.
5. Turn on the pen and chart. Then start the shear test.
6. Observe and record the maximum value obtained during
the complete separation of each of the specimen
combinations.
7. A total of 4 separate specimens will be tested and the
average calculated to characterize one sample.
