Note: Descriptions are shown in the official language in which they were submitted.
21~2~7~
WO 94/27648 PCT/US94/05417
WATER REPELLENT ORTHOPEDIC DRESSING
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continll~tion-in-part of U.S. patent
application Serial Number 08/069,868 filed June 1, 1993, which is a
c4~ u~1;nn-in-part of U.S. patent application Serial Number 07/703,038 filed
10 May 17, 1991, pen~ling~ which is a con~ tion of U.S. patent application
Serial Number 07/242,120 filed September 9, 1988, Ah~nrlQn
BACKGROUND
The present invention generally relates to me~ l dressings and
15 particularly relates to orthopedic dres~in~.~, such as padding and stocLinPttps~
which are used with casting m~tPri~l. The dressings of the present invention
are especi~lly useful when in contact with skin because the dressings are water
repell~nt and soil resistant but allow air and vapor to pass through the
dres~in~ ocesses to pr~a~e the m~tPriAl~ used to make the dressings of this
20 invention are described in the copending U.S. patent application Serial Number
07l703,038 filed May 17, 1991 which is incorporated by reference herein.
SUMMARY OF THE INVEN~ON
The present invention provides a water repellent orthopedic
25 dressing. The dressing is made from a soft, smooth, conformable,
air-pP-rmP~hle, hydrophobic fabric. The fabric contains polymeric fibers of an
extruded blend of thermoplastic polymer and a fluorochemie~l oxazolidinone.
These extruded fibers may be used to make a nonwoven fabric which is
particularly suited for use in cast or splint p~ ing. ~lle~ ely, the fibers
30 may be spun into yarns which may be used to make knitted or woven fAhncs.
A knitted fabric made from the extruded fibers is particularly suited for use instocl~inPttP~s and tubular stoc~ nettes.
Unexpectedly, the dressings made of the present extruded fibers
are .~ignific~ntly softer, smoother and more conformable when compared to
35 similar dressing that are surface only treated with water repellent mAtPri~l~ such
as fluor~chPmic~ls as described in U.S. Patent 4,989,593. The enhAnrP~ tactile
pl.)~.Lies of the present dressings provide water repellent fabrics which may bein direct contact with a patient's skin and provide both increased comfort to the
patient and reduced initAtion to the skin.
WO 94/27648 21~ 2 3 7 2 PCT/US94/05417
--2--
In addition, the pn)cessability and/or pe,ro,ll-ance of the extruded
fibers may be enh~nc~d by surface treating or coating the fibers with a
hydlophilic ~ntict~tic lubricant and a fluor~!chPmi~l water repellent. In the
embo limPnt of the invention, the hydr~l ilic lubricant aids pr~ g of the J
S fibers while the fluorochP-mi~l water repellent gives improved initial water
resi~t~nce.
P~ef~l~ thermoplastic polymers which are used to make the
present fibers include polyethylene, poly~ropylene and polyesters such as
polyethylene le~ephtl.Al~te as well as blends or copolymers thereof. Particularly
plcfe~lcd polymers melt at sufficiently low tclll~l~Llurcs to allow melt blen-lin~
of the polymer with a fluororhP-mic~l ox~7oli~linQne without degr~ tiQn of the
ox~7olidinone. ~lle. .~ re polymers include low mPltin~ non-reactive
colllpa~ible polymers. Polyethylene and polypropylene are plesel lly most
plcÇ~lcd polymers.
Suitable oxa_olidinones are described in U.S. Patents 5,025,052
and 5,099,026, which are incorporated by reference herein. A preferred
fluor~rhPmic~l ox~7o~ inQnp~ (available from 3M, St. Paul, MN) is
s~ AIi~lly r~)rcsented by the formula
C
o/ \N C18~7
C8~l,SO2N(~
This ~l~rt;lled oxazolidinone (referred to herein as ODOX) is
pf~ared according to le~l~d methods. Briefly, a perfluoroalkylsulfon~mide,
C8Fl7SO2N(CH3)H, is reacted with epichlorohydrin to provide the chlorohydrin,
C8Fl7SO2N(CH3)CH2CH(CH2Cl)OH. The chlorohydrin is then reacted with an
octadecylisocy~late, Cl8H37NCO, to provide an interme~ tP urethane which
cycliæs in the presence of base to provide the ox~70li(linQne listed above.
To pr~c; fibers for use in this invention, the polymer and
fluorot~hPmic~l oxazoli~inonP are melt blende~ and then extruded into fibers
using known appal~lus and processes to provide fibers having belwæll about
~ wo 94,27648 2 1 fi 2 3 7 ~ PCT/US94/05417
--3 - .
0.1-10.0 wt. % oY~7oli~linone, and more preferably between about 0.3-3.0 wt. %
oxazoli(linone. These fibers may then be used to pr~ale nonwoven, woven or
knitted fabrics using known procedures. In ~ lition, extruded fibers which
have been çrim~ and oven-dried may be coated with a ~ u~e of ~nti~t~tic
S lubricant and fluorochPmir~l water repPllçnt and then cut into staple fibers to be
used to l,re~a.~ nonwoven, woven or knitted fabrics using known procedures.
- DETAILED DESCRIPr'ION
Orthopedic casts and splints may be made from a water curable
10 resin ipreg,-~ted casting m~t~ri~l that is used in combination with a soft layer
of p~1flin~ applied between the load-bearing casting m~tt~ri~l and a patient's
skin. The p~lrling is used to provide cushioning and protection to the skin and
is pre~,ed to be comfortable, easy to apply, non-irritating as well as quick
drying. When a cast is made, generally a stretchy knit tubular stockinPtte is
applied over a patient's limb, a p~ ling is then wrapped over the stockinette,
and the casting m~t.ori~l is then applied over the cast padding. When a splint is
made, a layer of padding alone is typically used
In the present spe~ific~tinn, the following terms are defined as
follows.
NWater Repellent" means the ability of a fabric to cause water to
bead or be repelled from a surface as well as c~u~ing water which is
m~h~ni~-~lly or otherwise forced into the fabric to readily run out, leach out or
be removed from the interstices of the fabric.
"Conformability" means the ability of a fabric to easily or readily
deform around an object. A qu~ntit~tive measure of conformability is provided
by the HANDLE-O-METER stiffn~cs test set out in Example 2, below.
NSmooth" means the tactile feel or texture of the surface and may
be co.ll~aldlively measured using a surface friction test set out in Example 3,
below.
"Soft" means the subjective tactile sen~tion of the fabric on the
skin. Comp~rative softness of the present invention in relation to other water
repellent fabrics or dressings is described in Example 4, below.
"Hydrophobic" is a measure of the ability of the fabric to hold or
absorb water on the fabric surface. A measure of hydrophobicity is provided
by a measurement of a m~t~ri~l's surface energy which is readily determined
wo 94/2764~ 1 ~ 2 3 7 ~ PCT/US94/05417
using the modifi~ AATCC Test l~eth~d 118-1983 set out in U.S. Patent
5,027,803. P~erel~ed dressings of this invention have surface energies less thanabout 40 erg/cm2 and more preferably less than about 30 erg/cm2.
Suitable fluoroçh~omi~l water rep~llent~ for use in the present
S invention are those used in the m~mlf~rtllre of textile ar~cles. In the
m~nl~f~ctl~re of textile articles, such as carpet and apparel, or for eY~mple,
other fibrous ~ubsll~tes such as paper and leather, it is common to treat such
~ulJ~ tes with fluo~or~ r~l~ to impart oil and water repellency to the surface
of such m~ri~l~ Suitable fluorochemi~ for this use and their application to
fibrous substrates are described in various publications, e.g., U.S. Patent Nos.2,803,615 (Ahlbrecht et al.), 2,934,450 (Brown), 3,068,187 (Bolstad et al.),
3,094,547 (Heine), 3,329,661 (Smith et al.), 3,341,497 (Sherman et al.),
3,398,182 (Guenthner et al.), 3,458,571 (Tokoli), 3,462,296 (Raynolds et al.),
3,574,791 (Sherm~n et al.), 3,728,151 (ShPrm~n et al.), 3,896,251 (T~n~lcci),
3,916,053 (Sherman et al.), 4,013,627 (Temple), 4,024,178 (T~n~ucci),
4,029,585 (Dettre), 4,034,964 (Sherman et al.), 4,144,367 (Landucci),
4,160,777 (Loudas), 4,165,338 (R~t~uchim~ et al.), 4,190,545 (Marshall),
4,215,205 (T~n~ cci), 4,264,484 (Patel), 4,325,857 (Ch~mp~neri~ et al.),
4,340,749 (Patel), 4,401,780 (Steel), 4,426,476 (Chang), 4,525,305 (Patel),
4,525,423 (Lynn et al.), 4,529,658 (Schwartz et al.), 4,540,497 (Chang et al.),
4,560,487 (Brinkley), 4,564,366 (Patel), 4,565,641 (Chang et al.)
4,566,981 (Howells), 4,579,924 (Schwartz et al.), 4,582,882 (Lynn et al.),
4,606,737 (Stern), 4,668,406 (Chang), 4,668,726 (Howells) and Banks, R. E.,
Ed., "Organofluorine Chemif~l~ and their In~llstri~l Applications", Ellis
Horwood, Ltd., West Sussex, Fn~l~n~, 226-230 (1979).
The ~fe~led fluo~ e..~ic~l water repellent is SCOTCHGARD
brand carpet pr~te~;lor (FC-359) an aqueous emnl.~ion of a fluorinated
polycarbo liimi~e of the type described in U.S. Patent 4,560,487, a flllo. ;~ edemul~ifier, CH3
C8F~7SO2N (CH2) 2N (CH3) 3Cl
and a fluorochPmic~l copolymer of the type generally described in U.S. Patent
3,916,053 and more specifically described in U.S. Patents 3,574,791 and
3,728,151.
Suitable hydrophilic lubricant ~nti~t~tic agents for use in the
invention are any such agents conventio~lly used in the fiber industry such as
Sipo Lube GS-1031, Synthetic Tnr~lstri~s, Inc., Chick~m~llg~, GA.
~WO 94/27648 21 ~ ~ 3 7 2 PCT/US94/05417
The following eY~mples provide ~lef~lled methods and
procedures for pr~-ticing the present invention. These examples further
illustrate various emboAim~Pnt~ of the present invention and should not be
construed to limit the scope of the invention which is set out in the appended
claims.
E~m~le 1 - Fiber Preparation
A poly~r~ylene/oY~7~ 1inone conr~ lt~ was made using a
40 mm twin screw extruder (l~estorff, Charlotte, NC) from virgin
poly~l~ylene (90 wt. % polypr~lene, #3661-Fiber Grade, Fina Oil &
ChPrnit~l Co., Dallas, TXl and a fluor~h~mif~l oxa_olidinone (10 wt.%
oY~7~ inone, ODOX described above, Protective Chemi~ Division, 3M, St.
Paul, MN). The res-llting polyl,lo~ylene/oxa_olidinone concentrate (10 wt. %)
was metered into a 160 mm barrier-type double flight extruder with additional
poly~r~ylene (90 wt.%, #3661-Fiber Grade, Fina Oil & Chemical Co.), and
the blend was melted with mixing at about 232-249C for about 1-3 minutes.
The melted Illi~Ul'~; of poly~lopylene and oxazolidinone was extruded into 3
denier fibers. The extruded fibers were crimped, oven dAed and cut to staple
fibers of 3.81 cm or 4.76 cm in length. A fluorine analysis of the staple fibersin~ ~ted that the fluorochemical content of the fibers was between about
0.88-1.2 wt. ~o .
This measurement provides an index of the amount of flllorine
present on a fiber. Briefly, organic fluorine is converted to inorganic fluorideion by burning a test sample in a sealed polycarbonate flask, via an electronic
ignition system, in the presence of oxygen and a known volume of deionized
water. The inorganic fluoride ion is absorbed into the water. The fluoride ion
is measured using a fluoride ion sE~-ific electrode, Model #94-09 Fluoride Ion
Electron commercially available from Orion Research Inc., Boston, MA.
The shorter 3.81 cm extruded fibers were then processed into
nonwoven cast p~l~ling using standard methods by Astro-Form Corporation,
Danielson, CT, using commercially available Randoweb Equipment. Padding
rolls 7.62 cm and 10.16 cm wide were also ~l~ared and evaluated.
The extruded polypropylene/oxazolidinone fiber pa~ing had a
lower than normal, compared to un~eated polyester p~-lding (Synthetic Cast
J 35 Padding, MW 03, 3M, St. Paul, MN), tear strength as determined by m~ml~lly
tearing the fabric ~rr.su.l-ably because of the fiber length. The coextruded
wo 94,27~ 2 1 6 2 3 7 ~ PCT/US94/05417
-6-
~1fling was very soft, c~nform~hle and had a very good re~ t; nre to water.
When 4.76 cm extruded fibers were used to make a p~drling the tear strength
was equivalent to that of the u ,-t.~ted polyester pad-~ing.
The longer 4.76 cm extruded fibers were spun into 20 (cotton
5 count) single yarn using well-known processes by Doran Textiles, Shelby, GA.
The yarn was then knitted into stoc~inPtte rolls 5.08 cm and 7.62 cm wide by
Balfour, Inc., Rockwood, TN, using commercially available circular Rib-Knit
iplllellt. The poly~r~lene/oY~7nli~inone stocl~inPtte was also very soft,
c4nfo~ hle and had a very good re~i~t~nce to water.
FY~mple 2 - Conformability Test
This test measured the stiffnP~ or hand of a nonwoven fabric.
Confol...able fabrics were more flexible and less stiff when cG-.,pa cd to fabrics
which were not as conformable. To measure the stiffnPss of a nonwoven
15 fabric, the nonwoven m~tçri~l was deformed through a restricted opening usinga plunger and the force required to do this was measured using the INDA
Standard Test, HANDLE-O-METER Stiffness Test, IST 90.3 - 92 following
Lcd procedures.
The confo,...ability was measurPd for three different pi.~i~inf~.
20 An extruded polypropylene/oxazolidinone p~lrling was prcparcd from 3.81 cm
fibers according to Example 1.
Surface treated p~ linp was prepared using standard polyester
p;1~-1ing (Synthetic Cast Padding, MW 03, 3M, St. Paul, MN) that was dipped
in a 2 wt. % aqueous fluorochemical solution (FC-270 fluorochPmir~l water
25 repellPnt 3M, St. Paul, MN). The excess fluoroc-h~prni~i~l solution was
removed by wringing between two rollers and the surface treated padding was
then dried in an oven at 65.6C for about 24 hours.
Ur L-eated polyester p~dding was a commercially available
standard polyester p~ ling (Synthetic Cast Padding, MW 03, 3M, St. Paul,
30 MN).
The conformability data measured for the three p~d~ing~
(~mples evaluated were 7.62 cm x 15.24 cm) are provided in Table 1, below.
The data (the average force calculated from three runs) in~iri te that the
extruded poly~r~ylene/oxazolidinone p~ ling was more confo,.,.able when
35 co..,~arcd to a p~dding that was surface treated with only a fluor~hrmir~l
water repellrnt
~WO 9~127C48 ~ PCTIUS94/05417
TABLE 1
PADDING AVERAGE FORCE
unlleated polyester 2~.5 g
surface treated polyester 46.5 g
Sextruded polypr~l)ylene/oxazolidinone blend 31 g
P.~nlple 3 - Surface Friction Test
This test measured the surface friction of a sample which may be
10 used to evaluate the feel of the fabric. The test involves pulling a st~inlP-~s steel
boat covered with TRANSPORE tape (3M, St. Paul, MN) across a surface of
the sample and m~uring the force required to move the boat. The more force
~uilcd to move the boat across the sample, the greater the surface friction of
the sample. The requisite details for p~lrOl".il~g this test are described in U.S.
15 Patent 4,667,661.
The surface friction was measured for both nonwoven p~Ming
and knitted storlrinettes. The extruded p~lding and stockinette were l,l~ared
according to FY~mrl~ 1, above. The surface treated p~ ing and stockin~-tt~
were prt;~ d as described in Example 2. The untreated Synthetic Cast
20 Padding, MW 03, and unlleated MS 03 stor~in~tte were both available from
3M, St. Paul, MN.
The data measured for the different m~t~ns~l~ are provided in
Table 2, below. The data (the average force calculated from three runs)
in~ te that the extruded polypropylene/oxazolidinone pad~ing and stockinptte
25 both had greater surface friction when compared to the corresponding p~drlingor stoc~in~o-tte that was surface treated with water repellent m~t~ri~ d
according to Example 2.
TABLE 2
AVERAGE FORCE TO
PADDING MOVE BOAT
ul~r~ted polyester 68.25 ~
surface treated polyester 85.19 g
extruded polyl,r~,l)ylene/oxazolidinone blend 58.10
STOCKINElT~
untreated polyester 76.51 g
surface treated polyester 80.71 ~
extruded polyl .oL)ylene/oxazolidinone blend 63.80 g
Wo 94/27648 216 ~ 3 7 2 ` PCTIUS94/05417
. . - ~ - --8--
~ .
F~ ?le 4 - Softness Test
This eY~mrle provided the results of a test panel that subjectively
evaluated and col-lpa~ed the sorl-~ess of different p~ ing and stocL in~otte
m~t~ri~ls In this example, three p~d-lin.~ m~t.ori~l~ (an extruded
S poly~ ylene/oxazoli~linrn~ p~ ling, a surface treated p~ iin~, and an
u~ cated p~ lin~ p~ ed according to Example 3) and three stoc-Li.~lles (a
stoe~ e made with extruded poly~r~ylene/oxazolidinone fabric, a surface
treated ~locL;,~ tte, and an unLIeated stocLin~tte also p~t;d according to
FY~mrle 3) were ev~ t~
Briefly, each evaluator was asked to rank the p~rling or
SI~L ;l~ette m~t~ri~l in order of softness. The identity of the m~t~.ri~l~ was not
provided to the evaluators. After the m~tP.ri~ls were ranked, the ev~ tor~
were then asked to assign a softness value to the m~ l using a softness scale
of 1-20, with a value of 1 being the softest and co",pa,~ble to the softness of a
15 cotton ball. The results of this evaluation are listed in Tables 3 and 4.
TABLE 3
Padding Softness Test
Softness Softness Softness Softness Softness Softness
Rank Value Rank Value Rank Value
Evaluator first 1-20 second 1-20 third 1-20
C 1 B 2 A 15
2 C 1 s 3 A 10
3 c lo B 14 A 19
4 C S s lo A 20
s C 2 B 4 A 10
6 C 2 B s A 10
7 c 2 s 3 Al 15
average 3.29 5.86 14.14
value
M lC- A - ~urface treated polyester padding
B - e~kuded polypropylene/~ 7~ lin~ nP padding
C - ullh~ d polyester padding (MW 03 padding)
~Wo 94/27648 2 i 6 ~ 3 7 ~ PCT/US94/05417
g
TABLE 4
Sfockinette Softness Test
Sof~ess Sohless Sof~ess SohnessSoftness Soh~ess
Ranlc Value Ran~ Value Rank Value
S Evaluator first 1-20 second 1-20 third 1-20
A 4 C 6 B 10
2 A 2 C 3 B 15
3 A 8 C 12 B 18
4 A 5 C 10 B 15
A 5 C 10 B 15
6 A 3 C 10 B 15
7 A 5 C 8 B 10
average 4.57 8.43 14.0
value
r~ A - ~ t~ ~ polyester ~ (MS 03 rl~Y~
B - surface treated polyester ~ Y L ;... ~
C - e~truded pol~.u~J ¦~,.,C/~ ~7n~ ;nf~ IR
The data in Tables 3 and 4 inrlic~te that the extruded p~d-ling and
stockinette are significantly softer than a surface treated p~d~ling or stoc~in~tte.
Example S - Extruded Polypropylene/Oxazolidinone Splint Padding
Multi-layer immobilization splints were constructed and evaluated
for water absorption and water retention.
Briefly, the bottom layer of each splint was a 30.48 cm long and
8.89 cm wide p~d~ling made either from needle-tacked
poly~f~ylene/oxazolidinone fibers (99.3 wt % polyL,lo~ylene, 0.7 wt. %
oY~7~1idinone, ODOX described above, 3M, St Paul, MN) or from
needle-tacked untreated polypropylene fibers. Needle-tacking was carried out
using a Hunter Needletacker (Morse and Berkshire Company, North Adams,
MA). Both of the above fibers were needle tacked into nonwoven felts of about
340.2 g per 0.84 square meters.
t A strip of 1.27 cm transfer tape No. 950 (3M, St. Paul, MN)
was adhered to the long edges of the p~dtling and a strip of 3.81 cm transfer
tape No. 927 (3M, St. Paul, MN) was adhered to the short edges of the
p~r1rling, Next, eight layers of 25.4 cm long and 7.62 cm wide resin
i",~l~n~t~ SCOTCHCAST 2 brand fiberglass casting tape (3M, St. Paul,
216237~
WO 94/27648 PCT/US94/05417
-10-
MN) was cenl~ed on the layer of p~lding. Finally, a layer of commercially
available spun-laced, hydr~ gled nonwoven polyester fabric (SONTARA
8000, DuPont, Wilmington, DE treated with 2% fluoroc-h~mi~l water
repell~nt FC- 270, as described in U.S. Patent 5,027,803) was adhered to the
5 ~d~ling layer using the transfer tapes.
The water absorption and retention was dete ...in~d for each
splint. The splints were weighed dry, placed in a pan of water and im~
for 0.5 minute (hol~ing the splint under water if n~s~.y) while squ~.~ing
twice, removing the splint from the water, sque~ing the splint twice using two
10 hands, ~en weighing again. Each splint was set in a dry pan to cure and
allowed to air dry for 5 hours and weighed again.
When cured, the multiple layers of the splint bonded to~ether to
form a cohesive l~min~tç and the extruded polypropylene/oxazolidinone pad-ling
was softer and smoother when co--,pared to the u~ eale;d p~ ling. The splint
15 also had desirable water absorption and retention ~-o~lLies.
TABLE 5
Splint Padding Water Absorped (%) After 5 Hours - Retained (%)
1.875 inch (4.7625 cm) 67 SS
20 pol~ u~ ,c/0~7~ in~n~ fibers
needle-tacked at 128 needles/in2
3.25 inch (8.255 cm) pol~.u~ 72 61
fibers needle-tacked at 128 needles/in2
25 Percent water ~ or retained was ~ using the formula
(wet splint-dry splint) ~ 100
dry splint
30 Fy~mple 6 - Lubricated Water Repellent Fibers
Using the method and m~t~ lc described in Example 1, 4364 kg
of polypr~ylene and 1091 kg of a ~,.ixlure of 90% polypropylene and 10%
fluoroçh~mi-~l oxazolidinone was mixed to give a 98/2
poly~l~ylene/oxazolidinone mi~lule which was extruded into 3 denier fibers.
35 The extruded fibers were crimped, oven-dried, and then treated by kiss coating
using a convehlional smooth cylinder-type coating apparatus with a nli~lUr~, of
205.6 kg of a hydrophilic ~nti~t~tic lubricant Sipo Lube GS-1031 commercially
available from Synthetic Tndllstrips~ Inc., Chi~m~l-g~, GA and 36.4 kg of
~ wO 94n7648 2 ~ ~ 2 ~ 7 2 p(~Tllrss4lo54l7
SCOTCHGARD brand fabric ~r~t~;l~r, FC-359, a fluorochP-mic~l n~ lur~
commercially available from 3M, St. Paul, MN. The fber was then cut as in
F~mrle 1 into staple fibers 3.81 cm and 4.76 cm in length.
Some of the 3.81 cm fiber was l)roc~ into nonwoven cast
S p~lclinE using a co-,ve-.t;on~1 Randoweb E~luipment by Astro-Form
Co,~l~lion, n~niel~on~ CT. Padding rolls 7.62 cm and 10.2 cm wide were
ple~r~d and evaluated using the mndifi~ AATCC Test Method describe~
above. The surface energy of the fibers was found to be in the range of 26.4 to
27.3 ergs/cm.
Some of the 4.76 cm fiber was spun into 20 (cotton count) single
yarn using well-known pr~cesses by Southern Indl-~tri~l, Rossville, GA. The
yarn was then knitted into stocl~inette rolls 5.08 cm and 7.62 cm wide by
Balfour, Inc., Rockwood, TN, using commercially available circular Rib-Knit
Equirment The stoc~inlotte was evaluated using the modified AATCC Test
Method and found to have a surface energy in the range 26.4 to 27.3 erg/cm.
