U.S. patent application number 10/032693 was filed with the patent office on 2003-07-17 for odor control cassette.
This patent application is currently assigned to Playtex Products, Inc.. Invention is credited to Brown, Jeffrey, Chomik, Richard S., Yoho, Mark.
Application Number | 20030131569 10/032693 |
Document ID | / |
Family ID | 21866326 |
Filed Date | 2003-07-17 |
United States Patent
Application |
20030131569 |
Kind Code |
A1 |
Chomik, Richard S. ; et
al. |
July 17, 2003 |
Odor control cassette
Abstract
A film is provided for use in a cassette. Preferably, the
cassette is used in a waste disposal system. The film is a high
density polyethylene film resin having both a low melt index and a
high density, thereby providing improved odor control capabilities
and enhanced tear strength and assembly strength.
Inventors: |
Chomik, Richard S.;
(Middlesex, NJ) ; Yoho, Mark; (Chagrin Falls,
OH) ; Brown, Jeffrey; (Charlotte, NC) |
Correspondence
Address: |
Charles N.J. Ruggiero, Esq.
Ohlandt, Greeley, Ruggiero & Perle, L.L.P.
10th Floor
One Landmark Square
Stamford
CT
06901-2682
US
|
Assignee: |
Playtex Products, Inc.
|
Family ID: |
21866326 |
Appl. No.: |
10/032693 |
Filed: |
January 2, 2002 |
Current U.S.
Class: |
53/567 ;
206/576 |
Current CPC
Class: |
B65F 1/062 20130101;
B65F 2240/132 20130101; B65F 2210/1675 20130101; Y10T 428/139
20150115; Y10T 428/31855 20150401; Y10T 428/1397 20150115; B65F
1/0026 20130101; Y10T 428/1362 20150115 |
Class at
Publication: |
53/567 ;
206/576 |
International
Class: |
B65B 009/10 |
Claims
What is claimed is:
1. A non-resilient flexible tubing for use in a cassette for a
disposal system, said tubing being positioned in an annular space
of the cassette and adapted to form discrete areas of enclosure of
waste, said tubing comprising a high density polyethylene film
resin with both a low melt index and a high density.
2. The tubing of claim 1, wherein said film is a high density
polyethylene film resin with a melt index in the range 0.04 g/10
min to 0.50 g/10 min.
3. The tubing of claim 1, wherein said film is a high density
polyethylene film resin with a density in the range 0.90 g/cm.sup.3
to 0.99 g/cm.sup.3.
4. The tubing of claim 1, wherein said film is a high density
polyethylene film resin with an Elmdorf tear strength in a mold
direction in the range 9 g to 20 g.
5. The tubing of claim 1, wherein said film is a high density
polyethylene film resin with an Elmdorf tear strength in a
transverse direction in the range 30 g to 400 g.
6. The tubing of claim 1, wherein said film is a high density
polyethylene film resin with a tensile strength at break in a mold
direction of 7,000 psi to 13,000 psi.
7. The tubing of claim 1, wherein said film is a high density
polyethylene film resin with a tensile strength at break in a
transverse direction of 6,000 psi to 10,000 psi.
8. The tubing of claim 1, wherein said film is a high density
polyethylene film resin with an elongation at break in a mold
direction of 250% to 500%.
9. The tubing of claim 1, wherein said film is a high density
polyethylene film resin with an elongation at break in a transverse
direction of 300% to 700%.
10. The tubing of claim 1, wherein said high density polyethylene
film resin is formed into the tubing with a thickness in the range
of 7 .mu.m to 30 .mu.m.
11. The tubing of claim 1, wherein the high density polyethylene
film resin includes a colorant.
12. The tubing of claim 1, wherein the high density polyethylene
film resin includes a deodorant.
13. The tubing of claim 1, wherein the high density polyethylene
film resin includes a fragrance.
14. A cassette for dispensing film in a waste disposal system
comprising: a body having a top, said body defining an annular
space therein, said body being adapted to rotate in a container of
the system, a length of non-resilient flexible tubing positioned
for use in a tight layer in said annular space, said tubing being a
film having odor control capability and high tear strength, wherein
said tubing is dispensed through the top of said body when said
body rotates to seal said tubing, and wherein said film is formed
of a high density polyethylene film resin with both a low melt
index and a high density.
15. The cassette of claim 15, wherein said film has said melt index
in the range 0.04 g/10 min to 0.50 g/10 min.
16. The cassette of claim 15, wherein said film has a density in
the range 0.90 g/cm.sup.3 to 0.99 g/cm.sup.3.
17. The cassette of claim 15, wherein said film has an Elmdorf tear
strength in a mold direction in the range 9 g to 20 g.
18. The cassette of claim 15, wherein said film has an Elmdorf tear
strength in a transverse direction in the range 30 g to 400 g.
19. The cassette of claim 15, wherein said film has a tensile
strength at break in a mold direction of 7,000 psi to 13,000
psi.
20. The cassette of claim 15, wherein said film has a tensile
strength at break in a transverse direction of 6,000 psi to 10,000
psi.
21. The cassette of claim 15, wherein said film has an elongation
at break in a mold direction of 250% to 500%.
22. The cassette of claim 15, wherein said film has an elongation
at break in a transverse direction of 300% to 700%.
23. The cassette of claim 15, wherein said film is formed into said
tubing with a thickness in the range of 7 .mu.m to 30 .mu.m.
24. The cassette of claim 15, wherein the high density polyethylene
film resin includes a colorant.
25. The cassette of claim 15, wherein the high density polyethylene
film resin includes a deodorant.
26. The cassette of claim 15, wherein the high density polyethylene
film resin includes a fragrance.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a flexible tubing for use
in a cassette dispenser for a diaper or similar waste disposal
device. More particularly, the present invention relates to barrier
films used for flexible tubing in such cassettes.
[0003] 2. Description of the Prior Art
[0004] Diaper disposal devices have become popular for the
convenient and sanitary disposal of diapers and related waste. A
conventional diaper disposal device has a pail that serves as a
storage chamber accessed via a closable lid and, a cassette
positioned in the pail and having a tubular core with a length of
flexible tube stored in the core. The diaper disposal system
operates by depositing a soiled diaper into the pail, rotating the
core, and twisting the flexible tube to create a seal above the
diaper. A second diaper may be disposed of by opening the lid,
inserting the second diaper, and pushing the previous sealed diaper
further into the storage chamber. A new seal is created by twisting
the tube above the newly deposited diaper. The process can continue
until the pail is filled. Consequently, the device stores the
discarded diapers in a series of individually wrapped packages in
the storage chamber. Each package is separated from adjacent
packages by twists in the tubing. Such a packaging and disposal
system is described in U.S. Pat. No. 5,813,200, assigned to Playtex
Products, Inc., the assignee of the present invention. A cassette
for use in a diaper disposal system is described in U.S. Pat. No.
4,934,529 to Richards et al., also assigned to Playtex Products,
Inc.
[0005] Diaper disposal containers, in addition to aiding in the
discrete and sanitary disposal of human waste, also provide a
method of reducing malodor by containing the waste in sealed
packages of flexible tubing. The flexible tubing currently employed
in the art is formed of a substantially air-impermeable material
such as Formosa E905 or Formosa FPC. However, the odor reduction
capability of a tubing formed of Formosa resin is limited by its
permeability. Over time, a significant amount of odiferous gas
permeates through the tubing material into the environment. Less
permeable materials have not been employed in the art because they
are ill-suited for the conversion process in which film from a roll
is inserted into a cassette. Less permeable materials are brittle
and the insertion process creates splits or openings in the film.
Such splits are axially formed, as a result of the molecular
orientation of the film during the blowing process. Also, the
rigidity of less permeable materials renders them ill-suited to the
twisting required for operation of a cassette.
SUMMARY OF THE INVENTION
[0006] It is an object of the present invention to provide a
flexible tube or tubing material for use in a cassette of a waste
disposal system.
[0007] It is another object of the present invention to provide
such a cassette in which the flexible tube has barrier properties
that substantially reduce malodor from discarded diapers.
[0008] It is still another object of the present invention to
provide a flexible tube material for use in a cassette of a waste
disposal system that is resistant to tearing and splitting.
[0009] It is a further object of the present invention to provide
such a flexible tube material that is inexpensive and easy to
manufacture.
[0010] These and other objects and advantages of the present
invention are provided by the use of a flexible tube material for
use in a cassette of a waste disposal system, in which the flexible
tube material has both improved odor control capabilities and
enhanced tear strength. The tube material of the present invention
is made of a high density polyethylene (HDPE) film resin that
exhibits a low melt index in combination with a high molecular
weight. The HDPE film resin exhibits both (1) odor barrier
properties by reducing the amount of odiferous gas that may
penetrate the film, resulting in better odor control, and (2)
enhanced or higher tear strength, enabling the HDPE material's
functionality in a cassette.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The foregoing and still other objects and advantages of the
present invention will be more apparent from the following detailed
explanation of the preferred embodiments of the present invention
in connection with the accompanying drawings.
[0012] FIG. 1 illustrates the cell set-up for the isostatic
permeation test; and
[0013] FIG. 2 illustrates organic transmission rate test
results.
DETAILED DESCRIPTION OF THE INVENTION
[0014] The present invention is described in the context of a
cassette for use in a disposal system, preferably a diaper disposal
pail or system. However, the dimensions and design of the cassette
may be modified to accommodate any waste material having an
unpleasant odor. Other such applications may include use in a trash
can, a medical waste receptacle, or a chemical waste
receptacle.
[0015] The cassette tube or tubing material has improved odor
control capabilities and enhanced tear strength. The cassette tube
material is formed of a high density polyethylene film resin that
exhibits a low melt index in combination with a high molecular
weight. These attributes insure that both barrier properties and
tear strength are retained. The melt index of the tube material is
in the range of 0.04 g/10 min to 0.50 g/10 min, and preferably is
0.10 g/10 min. The density of the tube material is in the range of
0.90 g/cm.sup.3 to 0.99 g/cm.sup.3 and preferably is 0.95
g/cm.sup.3. Additionally, the tube material has an Elmdorf tear
strength, in the range of 9 g to 20 g, and preferably 10 g, in the
molded direction, and in the range of 30 g to 400 g, and preferably
100 g, in the direction transverse to the mold direction. The tube
material also has a tensile strength at break, of 7,000 psi to
13,000 psi, and preferably 10,000 psi, in the molded direction, and
6,000 psi to 10,000 psi, and preferably 9,000 psi, in the direction
transverse to the mold direction. Also, the tube material has an
elongation at break, of 250% to 500%, and preferably 400%, in the
molded direction, and 300% to 700%, and preferably 500%, in the
direction transverse to the mold direction. Tube materials were
selected based on the results of the isostatic organic permeation
study described in the Example below.
[0016] The HDPE resin material selected for the tubing, with a
density in the range of 0.90 g/cm.sup.3 to 0.99 g/cm.sup.3, has
large molecules that, when incorporated into a film, leave gaps
smaller than those of conventional tube materials, thereby reducing
the amount of odiferous gas that may penetrate the film. The result
is better odor control and maximized barrier protection when used
in a cassette.
[0017] The tube material has increased tear strength, in addition
to a high molecular weight, enabling its use in an improved odor
control cassette. Normally, as polyethylene density increases (to
achieve higher modulus) other properties, such as tear strength,
decrease. However, the tube material of the present invention has
enhanced or high or increased tear strength, as well as high
molecular weight. These characteristics enable the tube material to
withstand twisting and insertion dynamics, without resultant
breakage, that is necessary to the function of the cassette.
[0018] The film made from the resin material disclosed has a
thickness in the range of 7 .mu.m to 30 .mu.m, depending on whether
the film is manufactured as an infant film or toddler film. Toddler
film is typically thicker than infant film, thereby providing
superior barrier properties.
[0019] The film is blown to a lay-flat dimension via a blown film
process. The gauge was kept constant thereby increasing barrier
properties. The reduced gauge offers the opportunity for reduced
raw materials, shipping and storage costs for the tubing material.
Additionally, an increased amount of tubing can be fitted into each
cassette, thereby prolonging use. A further benefit to the use of a
HDPE resin material for cassette tubing is that HDPE is less
expensive to manufacture than nylon materials typically employed in
a cassette.
[0020] One commercially available HDPE material suitable for use in
an improved odor control cassette is known as Alathon.RTM. XL5906
HDPE resin, marketed by Equistar. This HDPE is described in U.S.
Pat. Nos. 5,962,598 and 6,147,167, both assigned to Equistar, and
both patents are incorporated herein by reference. Alathon.RTM.
XL5906 HDPE possesses the following typical properties:
1 Property Test Method Units Values Density ASTM D-1505 g/cm.sup.3
0.959 Melt Index ASTM D-1238 g/10 min 0.057 Elmdorf Strength @
Break, 10(34) g D1922 MD(TD) Tensile Strength @ Break,
12,300(9,360) psi D822 MD(TD) Elongation @ Break, MD(TD) 300(350) %
D822 Secant Modulus, MD(TD) 181,000(186,000) psi D822
[0021] Another suitable, commercially available linear polyethylene
material is known as HiD.RTM. 9650 Blown Film Resin, marketed by
Chevron. HiD.RTM. Blown 9650 Film Resin possesses the following
typical properties:
2 Property Test Method Units Value Density ASTM D-1505 g/cm.sup.3
0.952 Melt Index ASTM D-1238 g/10 min 0.034 Elmdorf Tear Strength,
MD(TD) 16(400) g D1922 Tensile Strength @ Break, 50,990(43,410) psi
D822 MD(TD) Elongation @ Break, MD(TD) 460(650) % D822 Secant
Modulus, MD(TD) 709,670(826,800) psi D822
[0022] It should be noted that the odor control capabilities of the
HDPE film used in the cassette may be enhanced by the addition of
one or more deodorizers and/or fragrances. Additionally, for
aesthetic reasons, the HDPE film may have a color or a design
printed thereon.
EXAMPLE
[0023] An organic permeation study was undertaken to provide
barrier characteristics of various films for human fecal matter.
This data was developed by performing an isostatic transmission
rate study.
[0024] The organic compounds shown in Table 1 were combined in
equal amounts by volume. The multi-component mixture and the films
were placed in a remote cell as illustrated in FIG. 1. The top
sides of the films were continuously swept with a nitrogen carrier
gas in order to prevent any decrease in concentration gradient
across the film.
3TABLE 1 Table 1 shows the organic permeants used for the
permeation study. COMPOUND CLASS 1-Pentanethiol C5 mercaptan
Valeric acid C5 organic acid p-cresol Substituted phenol Indole
Aromatic heterocycle
[0025] The carrier gas stream was periodically monitored to
determine whether equilibrium had been reached. Once equilibrium
was achieved, the results were recorded. A MOCON ARMATRAN II
equipped with a capillary column and a flame ionization detector
(FID) was used for the analysis.
[0026] After all test films had reached equilibrium and the results
had been recorded, the measuring instrument was calibrated to the
four individual organic permeants: 1-Pentanethiol, valeric acid,
p-cresol, and indole. A three-point calibration was used for each
permeant.
[0027] The film was challenged with the permeant on one side, while
the flux from the other side is swept to a liquid nitrogen cooled
cryo-trap. The flux was concentrated in the cryo-trap and then
flashed into a capillary column where the individual components
were separated. The components were then quantified at the FID and
the results were recorded. The transmission rate was calculated
based on the component quantification, the area of sample, and the
accumulation time in the cryo-trap.
[0028] A baseline was determined prior to the permeation study in
order to isolate the permeants in question. The results are given
for oxygen, water vapor and organic molecule transmission. For the
results shown, the Chevron HiD.RTM. 9650 and Equistar XL5903 films
exhibited the best barrier properties. Commercially used films,
such as Formosa E905, Formosa FPC and Chevron 9640, behaved in a
manner similar to one another and the co-extruded multiple layer CX
film exhibited the worst barrier properties.
4TABLE 2 Table 2 shows the organic transmission rate results.
Transmission rate (.mu.l/m.sup.2-day) 1- Valeric FILM Pentanethiol
acid p-cresol Indole TOTAL CX 9.22 .times. 10.sup.6 3.11 .times.
10.sup.4 3.27 .times. 10.sup.4 6.84 .times. 10.sup.5 9.97 .times.
10.sup.6 Formosa 4.34 .times. 10.sup.6 8.25 .times. 10.sup.3 2.55
.times. 10.sup.4 3.56 .times. 10.sup.5 4.73 .times. 10.sup.6 E905
Formosa 4.39 .times. 10.sup.6 8.89 .times. 10.sup.3 2.81 .times.
10.sup.4 5.33 .times. 10.sup.5 4.96 .times. 10.sup.6 FPC Chevron
4.51 .times. 10.sup.6 6.18 .times. 10.sup.3 2.70 .times. 10.sup.4
2.61 .times. 10.sup.5 4.80 .times. 10.sup.6 9640 Chevron 3.03
.times. 10.sup.6 1.94 .times. 10.sup.4 2.72 .times. 10.sup.4 2.28
.times. 10.sup.5 3.30 .times. 10.sup.6 9650
[0029] FIG. 2 is an illustration of the organic transmission rate
test results, which shows that the Chevron HiD.RTM. 9650 film has
superior barrier properties as compared to the Formosa films
currently used in Diaper Genie cassettes. FIG. 2 further shows that
Equistar XL5903 also has superior barrier properties as compared to
the Formosa films.
[0030] Equistar Alathon.RTM. XL5906 HDPE resin has similar
properties to Equistar XL5903 and, therefore, similarly provides
improved barrier properties when compared with Formosa films. A
separate study was undertaken to demonstrate the improved barrier
of the Equistar Alathon.RTM. XL5906 HDPE resin as compared to the
Formosa E905 film using pentanethiol as a permeant. The results are
shown below in Table 3.
5TABLE 3 Pentanethiol Transmission rate (.mu.l/m.sup.2-day) at Film
23.degree. C. Formosa E905 28.63 .times. 107 Equistar Alathon .RTM.
CL906 19.59 .times. 107
[0031] The Formosa E905 film produced a transmission rate of
28.63.times.107 .mu.l/m.sup.2-day at 23.degree. C. In contrast, the
Equistar Alathon.RTM. XL906 produced a transmission rate of
19.59.times.107 .mu.l/m.sup.2-day at 23.degree. C. The Equistar
Alathon.RTM. XL906 produced substantially less transmission of
pentanethiol and, therefore, has superior barrier properties
compared to the Formosa E905 film.
[0032] The present invention has been described with particular
reference to the preferred embodiments. It should be understood
that the foregoing descriptions and examples are only illustrative
of the invention. Various alternatives and modifications thereof
can be devised by those skilled in the art without departing from
the spirit and scope of the present invention. Accordingly, the
present invention is intended to embrace all such alternatives,
modifications, and variations that fall within the scope of the
appended claims.
* * * * *