U.S. patent number 3,716,430 [Application Number 04/871,131] was granted by the patent office on 1973-02-13 for tampon and process and apparatus for making the same.
Invention is credited to Nils Verner Blomqvist, Ingemar Croon.
United States Patent |
3,716,430 |
Croon , et al. |
February 13, 1973 |
**Please see images for:
( Certificate of Correction ) ** |
TAMPON AND PROCESS AND APPARATUS FOR MAKING THE SAME
Abstract
A composite tampon is provided comprising an absorbent layer of
cellulose pulp fibers, preferably cellulose fluff fibers, enclosed
within a wrapper layer which can be a non-woven material, or a
laminate between nonwoven material and cellulose pulp tissue.
Apparatus is also provided for preparing such tampons in a
continuous manner from cellulose fluff fibers and the wrapper
materials, folding or rolling the absorbent layer within the
wrapper in the form of a continuous elongated tampon, and then
cutting the column into lengths to form the tampon.
Inventors: |
Croon; Ingemar (Alfredshem,
SW), Blomqvist; Nils Verner (Ornskoldsvik,
SW) |
Family
ID: |
25356793 |
Appl.
No.: |
04/871,131 |
Filed: |
October 15, 1969 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
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662843 |
Aug 15, 1967 |
3523535 |
Aug 11, 1970 |
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606956 |
Jan 3, 1967 |
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Current U.S.
Class: |
156/62.4; 28/121;
156/203; 156/276; 28/118; 156/269; 425/82.1 |
Current CPC
Class: |
A61F
13/2085 (20130101); Y10T 156/1084 (20150115); Y10T
156/1013 (20150115) |
Current International
Class: |
A61F
13/20 (20060101); A61f 013/20 () |
Field of
Search: |
;128/260,263,270,285
;156/184,276,62.4,269,201,203 ;19/144.5 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Quarforth; Carl D.
Assistant Examiner: Lehmann; E. E.
Parent Case Text
This application is a division of Ser. No. 662,843, filed Aug. 15,
1967, now U.S. Pat. No. 3,523,535, patented Aug. 11, 1970, which is
a continuation-in-part of Ser. No. 606,956, filed Jan. 3, 1967, and
now abandoned.
Claims
Having regard to the foregoing disclosure, the following is claimed
as the inventive and patentable embodiments thereof:
1. A continuous process for preparing tampons which comprises
continuously and stepwise, in sequence, forming an extended layer
of loose cellulose pulp fibers having a length of up to 5 mm. on a
porous base; laying a sheet of wrapper material on the layer;
folding the layer and wrapper tightly lengthwise to form a column,
with the lapped ends of the wrapper sheet outermost, forming a
lapped seam, with the cellulose pulp fibers under compression
within the wrapper; bonding the lapped edges together to seal the
seam; and cutting the resulting column into lengths to form
tampons, each of the aforesaid steps being carried out
simultaneously with respect to each other, and stepwise with
respect to the tampons being prepared.
2. A process in accordance with claim 1, which comprises applying a
bonding agent to the lapped seam, to bond the lapped edges
together.
3. A process in accordance with claim 1, in which the cellulose
fibers are cellulose fluff fibers.
4. A process in accordance with claim 1, in which the wrapper is of
high wet-strength fibrous material.
5. A process in accordance with claim 4, which comprises bonding
the high wet-strength fibers together to aid in retaining the shape
imparted to the tampon.
Description
This invention relates to a tampon having an absorbent layer
composed of cellulose pulp fibers, and particularly cellulose fluff
fibers, and to a process and apparatus for preparing tampons of
this type, and more particularly to tampons made of absorbent
cellulose pulp fibers less than about 5 mm. in length, and enclosed
within a sheath of non-absorbent fibrous woven or nonwoven material
or a laminate between nonwoven fabric and cellulose pulp tissue,
and to a process and apparatus for forming the same.
It is generally accepted that a satisfactory tampon must have a
sufficient initial stiffness and rigidity to facilitate its
insertion in the body cavity, but at the same time should be
sufficiently soft or softenable in the body cavity so that its
presence is acceptable there without irritation. The tampon must
also have a high capacity for absorption of the desired body
fluids, and it must be capable of absorbing the desired body fluids
without disintegration, so that when it is necessary to remove it,
it can be removed intact.
After many years of development and evolution, the tampon in common
use today is made of absorbent cotton fibers, usually in the form
of cotton wadding, which is wound into the form of a cylinder, with
the aid of reinforcing material, and finally provided with a gauze
covering that resists disintegration in the body cavity. However,
it must be conceded that as a practical matter, tampons of this
type can nonetheless liberate cotton fibers in the body cavity, and
they also have a tendency to become far too soft, and lose their
shape, upon absorption of an appreciable amount of body fluids.
Typical tampons of this type are described in U.S. Pat. No.
2,099,931, dated Nov. 23, 1937, to Fourness, and U.S. Pat. No.
2,900,980, dated Aug. 25, 1959, to Harwood. Tampons are also known
which consist altogether of absorbent cotton fibers, the outer
layers of which are bonded together with glue. These tampons also
show the disadvantages mentioned above.
It has been suggested that synthetic mainly nonabsorbent fibers
such as acetate rayon be employed in place of cotton. Such fibers
are not capable of absorbing aqueous fluids, and consequently are
not softened by body fluids. However, a large proportion of the
absorbent capacity of a tampon made of cotton fibers is due to the
absorption by the fibers themselves, and consequently, tampons made
of acetate rayon, or other nonabsorbent synthetic fibers of this
type, have an insufficient capacity for absorption to make them
generally acceptable as a substitute for cotton fiber tampons. It
has also been suggested that fibers of regenerated cellulose (rayon
staple fibers) be employed in place of cotton. Such tampons show,
however, the same disadvantages as the cotton tampons described
above.
In accordance with the invention, tampons are provided in which the
absorbent material consists essentially of cellulose pulp fibers
that are less than 5 mm. in length. Such fibers due to their short
length give a dense, relatively noncompressible mass. The fibers
are quite absorbent. The absorbent material composed of these
fibers is enclosed within a wrapper or sheath of fibers having a
high wet strength, such as high wet modulus viscose or acetate
rayon fibers, associated as a nonwoven fabric. This sheath,
accordingly, is relatively unaffected by body fluids. The result is
a tampon that although highly absorbent is more dimension-stable
than prior tampons, and is therefore not readily susceptible to
disintegration after absorption of body fluids. Moreover, the wet
strength of the fibers of the wrapper makes it possible to employ a
synthetic resin binder therefor that is also unaffected by body
fluids, thus substantially preventing disintegration of the wrapper
while in use in the body cavity. This means that the cellulose
fibers of the absorbent layer can be prevented from detachment from
the tampon in use.
In a preferred embodiment of the invention, the cellulose pulp
fibers are enclosed within a sheath composed of a laminate between
nonwoven fabric and cellulose pulp tissue. Such a sheath has
superior strength and durability.
Further in accordance with the invention, process and apparatus are
provided for preparing such tampons in the form of an elongated
column, such as a cylinder. The process is susceptible of
continuous operation. Cellulose pulp fibers of the required length
are fed onto and laid down upon a porous base, and are held on the
base by suction from below and by some air pressure from above. The
fiber layer is built up to the desired thickness, and then the
layer is brought in contact with the sheet or wrapper material. The
composite is folded or rolled lengthwise, forming a bilayered
column with the wrapper as the outer layer forming a seam, which is
then bonded. If the fiber layer and the wrapper sheet are
continuously fed, it is possible to form an endlessly elongated
column of absorbent cellulose pulp fibers with the wrapper
constituting the outer layer, and this can be cut into any desired
length to form the finished tampon.
If a multiply sheath is employed, as in the preferred embodiment
described above, the multiple plies thereof are brought together
preferably with heat and pressure before they are brought into
contact with the layer of cellulose pulp fibers. The tampon is then
completed using the described procedure and apparatus.
The composite tampon that is obtained by this process is a
cylinder, comprising the absorbent layer of cellulose pulp fibers
on the wrapper layer wound about itself, with the wrapper layer
outermost, so that it serves as a protective outer layer. The
wrapper layer also serves as a reinforcing layer for the tampon,
and imparts rigidity. If the composite is tightly wound, the
absorbent layer can be compressed within the wrapper, increasing
the density of the composite. It is preferred that the density be
within the range from about 0.05 to about 0.3 g/cc., preferably
from 0.1 to 0.2 g/cc., which illustrates the high degree of fiber
packing that characterizes the tampons of the invention.
The tampon of this process will usually be cylindrical in
cross-sectional configuration, but of course any configuration can
be fashioned, such as polygonal, square, rectangular, or
elliptical, according to the end use intended. A cylindrical
composite is preferred. It is, of course, also possible to compress
only the absorbent layer of cellulose pulp fibers, and then in
another step enclose this material in an outer encircling wrapper
of wet strength fibers.
The apparatus in accordance with the invention comprises, in
combination, a porous base, preferably in the form of an endless
porous belt, means for laying down cellulose pulp fibers upon the
belt and forming a layer thereon, means for applying suction upon
the layer on the belt from below and a small air pressure upon the
layer on the belt from above, so as to hold the layer on the belt,
means for bringing a sheet of wrapping material into contact with
the fiber layer, means for folding or rolling the composite or
wrapper and fiber layer longitudinally to form a column, means for
sealing and bonding the lengthwise seam of the resulting column,
and means for cutting the column into lengths to form the
tampon.
It is important that the cellulose pulp fibers employed in forming
the absorbent layer of the tampons of the invention be less than 5
mm. in length. Fibers that are longer than this are too long to
form a dense relatively non-compressible layer. They are also
subject to breaking under wet conditions and therefore give a
weaker structure. It is preferred that the pulp fibers be less than
about 3 mm. in length. For maximum density and non-swellability, at
least 40 percent of the weight of the fibers should be less than
about 0.8 mm. in length.
Such cellulose pulp fibers are obtained by disintegration of wood
pulp in sheet or flash dried form, using mechanical disintegrating
apparatus. Such processes are well known, and form no part of the
instant invention. The process and apparatus must be of the type
that separates the fibers in an efficient way without cutting the
fiber too much. Over-cutting the pulp fibers results in cellulose
flour which is unsuitable for this invention, and the proportion of
which is therefore held to a minimum.
As a source of such cellulose pulp fibers, there can be used any
pulping wood, such as spruce wood, pine wood, hemlock wood, fir
wood, birch wood, and other types of coniferous and hard woods.
The cellulose pulp fibers that are preferred for use in the
invention are of the type called fluff. These are obtained by
disintegrating chemical cellulose pulp prepared by the sulphate or
sulphite method in such a way that the fibers are set free from the
pulp while at the same time avoiding the formation of fiber bundles
or knots and cutting of the fibers. This disintegration can be
carried out in a shredder or hammer mill or in a disk refiner or in
an apparatus comprising a set of circular sawblades mounted on a
rotating axis, or in a combination of these. For instance, the
chemical pulp in the form of sheets can be first roughly
dry-disintegrated in a shredder or hammer mill and then further
disintegrated in a disk refiner. If the pulp is in the form of
rolls, it is possible to disintegrate it directly in one step in a
hammer mill. It is not necessary, and in fact it is undesirable to
materially shorten the fibers of the cellulose pulp after such
disintegration, and therefore the disintegration technique and
apparatus used should be specially adapted to avoid this, using the
known techniques.
It is preferred that the cellulose fibers fall within the following
ranges of fiber length distribution, measured by the Bauer NcNett
method:
TABLE 1
Fiber Length Range (mm) Percent Distribution Less than 5 mm. but
more than 0.833 mm. 30 to 60 less than 0.833 mm. but more than
0.417 mm. 10 to 40 less than 0.417 mm. but more than 0.208 mm. 10
to 40 less than 0.208 mm. but more than 0.104 mm. 10 to 40 less
than 0.104 mm. 0 to 20
In fluff, the proportion of the median fraction of the fibers is
somewhat greater than in ordinary chemical pulp. As a result of
this difference, small as it is, in the distribution of fibers,
fluff fibers have a higher bulk and a greater absorption than
ordinary chemical pulp fibers.
Fluff fibers are rather different in physical nature from fibers of
cellulose pulp tissue which are also obtained from cellulose pulp,
but are prepared by a different process. Cellulose pulp tissue are
obtained by placing sheets or bales of chemical or mechanical
cellulose pulp in hollanders, where the pulp is beaten with water.
The suspension obtained can then be stored and is next transported
to beaters, after dilution to a pulp concentration of 0.5 to 1.5
percent. The beater can be a disk refiner, or a Jordan mill
employing a rotating cone, and the beating is mild. After the
beating, water is removed from the suspension in an uptaking
machine. The fiber length distribution of the resulting tissue
fibers is similar to that of fluff fibers, but the product is
paper-like, and not bulky. The absorption capacity of tissue fibers
is from one-third to one-fourth that of fluff fibers.
Consequently, cellulose pulp tissue are not desireable in the
absorbent layer of tampons in accordance with the invention,
because of their low absorption capacity.
Cotton cellulose fibers differ materially from cellulose pulp
fibers. They are materially longer, greatly exceeding 5 mm. in
length. Because of their length, they are subject to breakage and
rupture, and give tampons which are not as rigid as those obtained
using cellulose pulp fibers. Moreover, they are more expensive.
Consequently, they are not employed in the tampons of the
invention.
The wrapper or outer layer can be any porous sheet material that
has a high wet strength. By high wet strength according to the
present invention is meant from 3 to 6 kilograms per 50 millimeters
strip in the length direction and from 0.3 to 1 kilograms per 50
millimeters strip in the transverse direction as measured according
to TAPPI 456 m-49. Nonwoven mats, sheets and fabrics of
nonabsorbent synthetic fibers or impregnated or coated natural
fibers are preferred wrapper materials. The nonwoven materials are
cheap, and would normally be employed. These materials can be made
of any type of synthetic fiber, such as acetate rayon, nylon,
polyacrylamides, polyvinyl chloride, polyvinylidene chloride,
terephthalic acid-ethylene glycol polymers (Dacron),
polyacrylonitrile (Orlon and Vinyon N), polyethylene, and
polypropylene, or of natural fibers impregnated or coated with a
sufficient amount of such materials to render them nonabsorbent, or
of high wet modulus viscose rayon fibers.
For greatest strength and resistance to disintegration in use, the
fibers of the nonwoven wrapper material are preferably bonded at
their points of crossing by a synthetic resin binder material, such
as a thermoplastic or thermosetting resin. The amount of binder
that is employed should not materially reduce the porosity of the
wrapper, nor should the resiliency thereof be greatly affected,
since an unduly rigid wrapper material is hard to roll and handle
in the processing. Flexibility of the wrapping material is
desirable and has very little effect on the stiffness of the final
product, since the relative non-compressibility is obtained because
of the nature of the cellulose pulp fiber layer. This layer can be
rolled very tightly, and consequently is responsible for the
relative rigidity and non-compressibility of the tampons of the
invention as compared to the known products.
Among the binder materials that can be used are polyvinyl chloride,
polyethylene, polypropylene, nylon, polyacrylonitrile, ethylene
glycol-terephthalic acid copolymers, polyvinyl acetate, copolymers
of vinyl acetate and vinyl chloride, polyvinyl butyral,
polytrifluorochloroethylene, urea-formaldehyde,
melamine-formaldehyde, phenol-formaldehyde, and alkyd resins. It is
very suitable to use a binder comprising the same material as the
fibers. These can be formulated into binder compositions of
conventional type, including plasticizers, pigments, and fillers.
Such compositions are well known, and form no part of the instant
invention. In all cases, however, the binder composition should be
resistant to and insoluble in body fluids.
A multiply wrapper can have superior strength and durability, and
is preferred in many instances. Two or more plies of the same or
different materials can be employed. Nonwoven fibrous materials can
be used.
One preferred type of multiply wrapper is made of an outer layer of
nonwoven fibrous material, as described above, and of one or more
inner layers of cellulose pulp tissue. Cellulose pulp tissue is
made as previously described, and is distinct from fluff fibers
because of the different preparatory procedure. It is used to
strengthen the wrapper, and not to impart greater absorbency, nor
does it form a part of the absorbent fluff fiber layer.
The cellulose pulp tissue can be formed as separate tissue paper
layer and then combined with the nonwoven material with heat and
pressure to form the wrapper. Bonding of the tissue fibers to the
outer nonwoven ply is desirable. Any of the binding agents
mentioned above can be used for this purpose.
The cellulose pulp tissue ply and the outer plies can each have a
thickness ranging from 0.05 mm. to about 2.5 mm. The wrapper
overall can have a thickness of from about 0.1 mm. to about 5 mm.
The tampon's absorbent fluff fiber layer will have a diameter of
from three to fifty times the thickness of the wrapper.
The tampons in accordance with the invention can easily be prepared
on any base by laying down a layer of the cellulose pulp fibers,
and then rolling up the layer into an elongated column. Preferably,
the layer is laid down on the wrapper, and the composite folded
together so that the wrapper layer is outermost. This operation can
be conducted manually or by machine. The lap at the outer edge of
the column that is thus obtained is then bonded, so as to prevent
unrolling. However, for economy of production costs and greater
rate of production, it is preferred to prepare the tampons by a
continuous process, using apparatus provided in accordance with the
invention.
FIG. 1 represents a side view of a typical apparatus in accordance
with the invention designed to form an elongated continuous
cylinder that can be cut in sections according to the length of
tampon desired.
FIG. 2 represents a perspective view of a tampon produced by the
apparatus of FIG. 1.
The apparatus includes a disintegrator 1 for pulp sheets of the
hammer mill, disk refiner, or circular sawblade type, capable of
disintegrating the pulp sheets into separate fibers less than 5 mm.
in length. Pulp 2 is continuously supplied to the disintegrator
through line 3. In operating the disintegrator, air is sucked in
together with the pulp sheets, at the same time causing compression
of the air on the outlet side 5 of the disintegrator. The air
entrains the cellulose pulp fibers 6 as they emerge from the mill,
carrying the fibers, now airborne, through line 7 to an endless
wire mesh belt 10. The belt passes over drive rolls 8 and idler
rolls 9, which are adjustable to control belt tension. The eductor
fan 11 below the belt draws the air across the belt. The diameter
of the mesh openings of the belt, which can be made of stainless
steel wire mesh, is less than 0.1, preferably from 0.05 to 0.01
mm., which corresponds to from about 150 to about 800 mesh, so that
the fibers are filtered out from the air as it passes across the
belt, and are deposited on the belt in the form of a layer 12,
usually 1 to 10 mm. thick, which is held firmly down on the belt
under the air pressure of the air stream passing to eductor fan 11.
The rate of flow of the air stream in the line, and the rate of
production of fibers by the disintegrator, are matched with the
travel speed of the endless belt, so that a uniform layer of
cellulose pulp fibers is formed on the belt. This layer serves as
the absorbent layer of the tampons of the invention, as is best
seen in FIG. 2.
A sheet of wrapper and reinforcing material, in this case, a
nonwoven highly porous gauze 13 made of acetate rayon fibers bonded
together by a cellulose acetate binder, provided, if desired, with
a laminate between the nonwoven fabric and cellulose pulp tissue,
is fed from a rolled source of supply 15 over an idler roll 16 and
tensioning roll 17, and then over three guide rolls 18 to the top
of an endless feed belt 21 running over drive roll 19, and idler
roll 20. Roll 19 can be adjusted to control tension. Directly above
the belt 21 is a second endless belt 22, spaced therefrom by a gap
equal to or slightly less than the thickness of the layer 12 plus
the gauze 13. Belt 22 is driven by roll 23 at the same travel speed
as belt 21, and passes over two guide rolls 24 and a tensioning
roll 25.
The wrapper material 13 is arranged to enter the nip between the
belts 21,22 beneath the layer 12 of cellulose pulp fibers which is
fed in from belt 10. The composite layer of wrapper material and
cellulose pulp fibers, slightly compressed, if desired, in the nip
between belts 21,22, then passes through the former die 28, where
the composite is folded over on itself, wrapper layer outermost,
into a tampon cylinder 30, with the ends of the lapped sheet on
top, forming a longitudinal seam 31 (best seen in FIG. 2) running
the length of the cylinder. The kissing roll 32 applies a band of
adhesive 33 to the longitudinal seam, and sealing is completed by
the heated pressure rolls 35,36, which apply sufficient heat and
pressure to effect the bonding of the seam by the adhesive. This
secures the cylinder against unwinding. The knife blade cutter 37
is provided to cut the cylinder into the desired size of
tampon.
The apparatus as illustrated is intended to form tampons that are
cylindrical in cross-section. If a different type of cross-section
or configuration is desired, all that is necessary is to substitute
a suitably shaped forming die for the cylindrical forming die 28.
Thus, for example, a rectangular die will form a rectangular
tampon, an elliptical die will form an elliptical tampon, and so
on. The tampon will be set in this configuration by the
adhesive.
An adhesive is not needed to seal the longitudinal seam, if the
binder and/or some or all of the fibers of the wrapper are
softenable by heat. In this case, the temperature of the pressure
rolls is elevated to a point at which the fibers are softened, so
that the pressure rolls will bond the fibers at the lapped ends of
the sheet together, forming a seal. The bonded fibers when they are
hardened will retain this position. Moreover, the fibers will also
be set in the configuration of the tampon. In this way, it is
possible to produce a tampon having any desired cross-sectional
configuration, that will retain this configuration in use.
The following examples in the opinion of the inventors represent
preferred embodiments of this invention.
EXAMPLE 1
Employing the apparatus of FIG. 1, tampons were prepared made of
cellulose fluff fibers from spruce wood pulp, prepared by the
sulfite process. The spruce wood pulp in sheet form was fed to a
hammer mill disintegrator, where it was reduced to fluff.
The fluff fibers had the following fiber length distribution:
TABLE II
Percent by Weight Pulp Fibers Fluff Fibers Fiber Length Before
After Distribution Disinte- Disinte- (mm) gration gration less than
5 mm. but more than 0.833 mm. 59.3 55.7 less than 0.833 mm. but
more than 0.417 mm. 20.7 19.1 less than 0.417 mm. but more than
0.208 mm. 9.7 12.5 less than 0.208 mm. but more than 0.104 mm. 3.3
4.6 less than 0.104 mm. 8.0 8.0 Bulk (cc/g) -- 11.5
These fibers were made airborne, and carried thus from the
disintegrator to a stainless steel 320 mesh wire belt, where they
were laid down to form a mat, 8 mm. thick. This mat was brought
into contact with a nonwoven wet strength viscose rayon gauze, 0.1
mm. thick, having an average pore size of 100 microns, and bonded
by a polyvinyl acetate binder. The resulting composite was tightly
pressed together, and then formed longitudinally into a tightly
wound cylinder. A polyethylene emulsion adhesive was applied to the
longitudinal seam of the resulting cylinder, and this was set by
heat and pressure, so as to seal the seam and retain the
cylindrical configuration. The cylinder was then cut into one inch
lengths, to form tampons.
The wet strength of the tampons thus prepared was determined by
subjecting them to the following test procedure.
The tampon was transferred with a pair of nippers to the perforated
plate of a Buchner funnel, connected at the bottom to a niveau tube
placed at an equal level to the Buchner funnel. Water was added
with a burette to the niveau tube, so that the level of water was
at the upper part of the perforated plate of the Buchner funnel. By
means of capillary forces, water was then absorbed into the tampon.
The amount of water that was absorbed was noted, as well as the
physical condition of the tampon after the water had been
absorbed.
The tampon of the invention absorbed 9.7 g. of water per gram of
tampon. The tampon retained its shape and its strength
thereafter.
Using the same test, a commercially available tampon was evaluated
composed of rolled cotton, the outer side of which was glued
together with a water-soluble glue. This tampon swelled and burst
after absorbing 10.2 g. of water per gram. Another tampon of this
type, but from a different manufacturer, was tested. This one
swelled, and then went to pieces completely, so that it was
impossible to determine the amount of water absorbed.
It is apparent from the results of this test that the tampon of the
invention is quite desirable for use in dentistry. It is capable of
absorbing the saliva of the mouth during surgical operations. The
outer commercially available tampons tested would have been
unsatisfactory for this purpose, because bundles of fibers would be
separated from the tampons, and probably would find their way into
the wound, after which it would be necessary to pick out the fibers
with a pair of nippers.
EXAMPLE 2
Using the procedure of Example 1, tampons were prepared, elliptical
in cross-section, from cellulose fluff fibers prepared from sulfate
process pine wood pulp, disintegrated using a disk refiner to a
fiber length distribution similar to Table II. These were made
airborne, and laid down on a composite wrapper composed of an inner
(upper) ply of cellulose pulp tissue fibers, and an outer (lower)
ply of polyethylene fiber nonwoven mat, in which the fibers were
bonded to each other by application of heat and pressure. The
cellulose pulp tissue layer and the mat were each 0.1 mm. thick,
and the layer of cellulose fluff fibers was 6 mm. thick. This was
wound up longitudinally, to form an elliptical tampon with the
polyethylene mat outermost, and the entire mass subjected to heat
and pressure at a temperature just above the softening point of the
polyethylene fibers of the wrapper, so as to bond the lapped edges
of the longitudinal seam together, and retain the elliptical shape.
These tampons were cut into lengths 5 inches long, for use as
catamenial appliances.
It is apparent from the preceding disclosure that in accordance
with the invention tampons can be provided for any medical or
surgical use. The cellulose pulp fibers that are employed in the
absorbent layer have bulk and very high absorption capacity, and
because of its construction and the short length of the fibers, the
tampon retains its rigidity and strength even after absorption of a
considerable proportion of body fluids.
* * * * *