Information
-
Patent Grant
-
6607799
-
Patent Number
6,607,799
-
Date Filed
Thursday, October 15, 199826 years ago
-
Date Issued
Tuesday, August 19, 200321 years ago
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Inventors
-
Original Assignees
-
Examiners
Agents
-
CPC
-
US Classifications
Field of Search
US
- 428 401
- 428 417
- 428 418
- 428 422
- 428 423
- 428 43
- 602 52
- 602 54
- 602 55
- 602 57
- 602 58
- 602 59
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International Classifications
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Abstract
Adhesive composite dressings with simple and inexpensive delivery systems and methods of manufacturing the dressings are disclosed. The dressings include liners having a release surface and a retention surface. The bond strength between the liner and the pressure sensitive adhesive in the area of the retention surface is greater than the bond strength between the liner and the pressure sensitive adhesive in release surface. The increased bond strength in the area of the retention surface allows the backing to be held taut during delivery to assist in smooth aseptic delivery of the dressing. The retention surfaces can be provided by abrasion, embossing, perforating the liner, or combinations thereof. In addition, the methods of manufacturing the dressings can be practiced in-line with other converting operations using standard release liners.
Description
FIELD OF THE INVENTION
The present invention relates to pressure-sensitive adhesive composites having a delivery system and methods of using the composites as well as methods of manufacturing the composites. In particular, the present invention is useful in connection with very thin high moisture vapor permeable film wound dressings.
BACKGROUND OF THE INVENTION
The use of transparent film dressing continues to grow at an accelerated rate. In addition to their use as protective layers over wounds, where they facilitate healing in a moist environment while acting as a barrier to contaminating liquids and bacteria, the films are also used over catheters to prevent contamination of the catheter insertion site by contaminating liquids and bacteria. The films may also be used as surgical drapes because of their barrier properties. Dressings and drapes fitting the above description are available under a number of trade names such as TEGADERM™ (3M Company, St. Paul, Minn.), BIOCLUSIVE™ (Johnson & Johnson Company, New Brunswick, N.J.), OP-SITE™ (T.J. Smith & Nephew, Hull, England), and UNIFLEX™ (How Medica, Largo, Fla.).
The polymeric films used in those dressings and drapes, referred to as dressings below, are typically conformable. In other words, the films are extremely flimsy, flexible, and supple. They are typically supplied with a releasable protective liner covering the adhesive coated surface of the film. When the liner is removed, the adhesive coated film tends to wrinkle and adhere to itself, interfering with the smooth aseptic application of the dressing to a patient's skin. Various delivery systems have been proposed to address this problem.
U.S. Pat. No. 5,153,040 (Faase, Jr.) discloses dressing delivery systems in which a two-part liner is provided to protect the pressure sensitive adhesive on the bottom face of the film. Each liner includes an adhesion enhancement strip which is preferably permanently affixed to the pressure sensitive adhesive and film backing. During delivery, the adhesion enhancement strips are separated from the remainder of the film along perforation lines on opposite ends of the dressing. One disadvantage with this process is that it requires additional components, i.e., the adhesion enhancement strips located between the liner and the film, to accomplish the delivery system. Those additional components add to the cost and complexity of manufacturing the dressings.
U.S. Pat. No. 4,513,739 (Johns) discloses dressing delivery systems which also include a two-part liner and means for retarding weakness of the release liner from the adhesive on the film at opposite ends of the dressing. Like the delivery system described above, however, this system also requires the addition of components to the dressing to provide the differential release characteristics at the ends of the dressing. Among the additional components are different adhesives, backings with varying layer thicknesses, additional layers secured to the backing, folds in the liner such that the liner is directly connected to the backing over the ends of the dressing (see FIG.
5
), and additional components added to the ends of the dressing that attach the liner to the backing (see FIG.
6
). As above, the additional components add to the cost and complexity of manufacturing the dressings.
U.S. Pat. No. Re. 33,353 (Heinecke) discloses a dressing delivery system in which the liners are strip-coated with a release agent such that the ends of the liners are free of release coatings, which increases their adhesion to the pressure-sensitive adhesive on the bottom face of the backing. As a result, the backing can be suspended between two liners during delivery. After delivery, the end portions of the backing are preferably removed along with the attached liner. One disadvantage with this approach is that the strip-coated liner material must be stocked separately from liners in which the entire surface includes a release coating, thereby adding to the cost of manufacturing the dressings.
SUMMARY OF THE INVENTION
The present invention provides adhesive composite dressings with simple and inexpensive delivery systems. The dressings include liners having a release surface and a retention surface. The bond strength between the liner and the pressure sensitive adhesive in the area of the retention surface is greater than the bond strength between the liner and the pressure sensitive adhesive in release surface. The increased bond strength in the area of the retention surface allows the backing to be held taut during delivery to assist in smooth aseptic delivery of the dressing. The retention surfaces can be provided by abrasion, embossing, perforating the liner, or combinations thereof.
Advantages of the delivery systems provided by the present invention include the simplicity and ease with which the dressings can be manufactured. For example, a standard liner with a fully coated release surface can be used with the retention surfaces being formed in-line during the converting process. As a result, no special liners are needed in inventory.
A further advantage of the notched dressings of the present invention is that the notched portions of the dressing are maintained in tension, thereby assisting in delivery of the notched dressings over catheter insertion sites.
In one aspect, the present invention provides an adhesive composite dressing including a backing having top and bottom faces and opposing first and second edges; a pressure sensitive adhesive located on the bottom face of the backing; a liner comprising a release surface and an abraded surface, wherein the abraded surface is attached to the pressure sensitive adhesive along the first edge of the backing; and a handle attached to the backing along the second edge of the backing.
In another aspect, the present invention provides an adhesive composite dressing including a backing having top and bottom faces and opposing first and second edges; a pressure sensitive adhesive located on the bottom face of the backing; a first liner sheet including a first release surface attached to a portion of the pressure sensitive adhesive and a first abraded surface attached to the pressure sensitive adhesive along the first edge of the backing, wherein the strength of the bond between the first abraded surface and the pressure sensitive adhesive is greater than the strength of the bond between the first release surface and the pressure sensitive adhesive; and a second liner sheet including a second release surface attached to a portion of the pressure sensitive adhesive and a second abraded surface attached to the pressure sensitive adhesive along the second edge of the backing, wherein the strength of the bond between the second retainer and the pressure sensitive adhesive is greater than the strength of the bond between the second release surface and the pressure sensitive adhesive.
In another aspect, the present invention provides an adhesive composite dressing including a backing having top and bottom faces and opposing first and second edges; a pressure sensitive adhesive located on the bottom face of the backing; a liner comprising a release surface and a retention surface, the retention surface including a discontinuous release coating, wherein the retention surface is attached to the pressure sensitive adhesive along the first edge of the backing; and a handle attached to the backing along the second edge of the backing.
In another aspect, the present invention provides an adhesive composite dressing including a backing having top and bottom faces and opposing first and second edges; a pressure sensitive adhesive located on the bottom face of the backing; a first liner sheet including a first release surface attached to a portion of the pressure sensitive adhesive and a first retention surface including a discontinuous release coating, the first retention surface being attached to the pressure sensitive adhesive along the first edge of the backing, wherein the strength of the bond between the first retention surface and the pressure sensitive adhesive is greater than the strength of the bond between the first release surface and the pressure sensitive adhesive; and a second liner sheet including a second release surface attached to a portion of the pressure sensitive adhesive and a second retention surface including a discontinuous release coating, the second retention surface being attached to the pressure sensitive adhesive along the second edge of the backing, wherein the strength of the bond between the second retention surface and the pressure sensitive adhesive is greater than the strength of the bond between the second release surface and the pressure sensitive adhesive.
In another aspect, the present invention provides an adhesive composite dressing including a backing having top and bottom faces and opposing first and second edges; a pressure sensitive adhesive located on the bottom face of the backing; and a liner including a release surface attached to the pressure sensitive adhesive and a void formed through the liner, the void exposing a portion of the pressure sensitive adhesive, wherein the bond strength between the liner and the pressure sensitive adhesive is increased proximate the void.
In another aspect, the present invention provides an adhesive composite dressing including a backing having top and bottom faces and opposing first and second edges; a pressure sensitive adhesive located on the bottom face of the backing; a first liner sheet including a first release surface attached to a portion of the pressure sensitive adhesive and a first void exposing a first portion of the pressure sensitive adhesive; and a second liner sheet including a second release surface attached to a portion of the pressure sensitive adhesive and a second void exposing a portion of the pressure sensitive adhesive.
In another aspect, the present invention provides an adhesive composite dressing including a backing having top and bottom faces, opposing first and second edges; a pressure sensitive adhesive located on the bottom face of the backing; a liner attached to the pressure sensitive adhesive; means for increasing the bond strength between the liner and the pressure sensitive adhesive proximate the first edge of the backing; and a notch formed in the backing, pressure sensitive adhesive, and the liner, wherein the notch opens along the first edge of the backing and extends towards the second edge of the backing.
In another aspect, the present invention provides a method of manufacturing an adhesive composite dressing by providing a backing having top and bottom faces; providing pressure sensitive adhesive on the bottom face of the backing; providing a liner having a release surface and at least one retention surface; and attaching the release surface and the retention surface of the liner to the pressure sensitive adhesive on the backing.
These and other features and advantages of the articles and methods of the present invention are discussed below.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is a perspective view of one adhesive composite dressing according to the present invention.
FIG. 1A
is a perspective view of a liner.
FIG. 2
is a perspective view of the dressing of
FIG. 1
with the liner partially removed from the pressure-sensitive adhesive on the bottom of the backing such that the dressing is ready for placement on a patient.
FIG. 3
is a perspective view of a dressing according to the present invention located over a catheter on a patient.
FIG. 4
is a side view of the dressings of
FIGS. 1 and 2
.
FIG. 5
is a plan view of an alternative dressing according to the present invention.
FIG. 6
is a perspective view of one dressing according to the present invention including an abraded two-part liner.
FIG. 7
is a perspective view of another dressing according to the present invention including a two-part liner with voids formed therein.
FIG. 8
is a schematic diagram of one process for manufacturing dressings with an abraded liner according to the present invention.
FIG. 9
is an illustration of one abrading process for abrading a liner.
FIG. 10
is a schematic diagram of one process for manufacturing dressing with a perforated liner according to the present invention.
FIG. 11
is a schematic diagram of one process for perforating a liner.
DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS OF THE INVENTION
The present invention is particularly useful in the field of pressure sensitive adhesive dressings having high moisture vapor permeable film backings. Issued U.S. Pat. Nos. 3,645,835 and 4,595,001 and European Patent Application Publication No. 0 437 944 describe methods of making such films and methods for testing their permeability. Preferably, the film/adhesive composite dressings should transmit moisture vapor at a rate equal to or greater than human skin. In one aspect, the adhesive coated film may advantageously transmit moisture vapor at a rate of at least 300 g/m
2
/24 hrs/37° C./100-10% RH, more preferably at least 700 g/m
2
/24 hrs/37° C./100-10% RH, and most preferably at least 2000 g/m
2
/24 hrs/37° C./100-10% RH using the inverted cup method as described in U.S. Pat. No. 4,595,001.
The backing film is also preferably conformable to anatomical surfaces. As such, when the backing is applied to an anatomical surface, it conforms to the surface even when the surface is moved. The preferred backing is also conformable to anatomical joints. When the joint is flexed and then returned to its unflexed position, the backing stretches to accommodate the flexion of the joint, but is resilient enough to continue to conform to the joint when the joint is returned to its unflexed condition. A description of this characteristic of backings preferred for use with the present invention can be found in issued U.S. Pat. Nos. 5,088,483 and 5,160,315.
A description of some backings that may be preferred for use in the adhesive composite security articles of the present invention can be found in issued U.S. Pat. Nos. 5,088,483 and 5,160,315, as well as European Patent Application Publication No. 0 437 944.
Particularly preferred film backings may be selected from the group of elastomeric polyurethane, polyester, or polyether block amide films, or combinations thereof. These films combine the desirable properties of resiliency, high moisture vapor permeability, and transparency that may be preferred in the backings. Also, although the backings are depicted below as monolayer articles, it will be understood that they could include multiple layers as described in, e.g., European Patent Application Publication No. 0 437 944.
The preferred pressure sensitive adhesives which can be used in the adhesive composites of the present invention are the normal adhesives which are applied to the skin such as the acrylate copolymers described in U.S. Pat. No. RE 24,906, the disclosure of which is hereby incorporated by reference, particularly a 97:3 iso-octyl acrylate:acrylamide copolymer. Also preferred is an 70:15:15 isooctyl acrylate: ethyleneoxide acrylate:acrylic acid terpolymer, as described in U.S. Pat. No. 4,737,410 (see Example 31). Other useful adhesives are described in U.S. Pat. Nos. 3,389,827; 4,112,213; 4,310,509; and 4,323,557; as well as UK Patent No. 1280631 (see, e.g., polyvinyl ether adhesives) and European Patent Nos. 35399 and 51935. Inclusion of medicaments or antimicrobial agents in the adhesive is also contemplated, as described in U.S. Pat. Nos. 4,310,509 and 4,323,557.
The preferred pressure sensitive adhesives described above preferably transmit moisture vapor at a rate greater to or equal to that of human skin. While such a characteristic can be achieved through the selection of an appropriate adhesive, it is also contemplated in the present invention that other methods of achieving a high relative rate of moisture vapor transmission may be used, such as pattern coating the adhesive on the backing, as described in U.S. Pat. No. 4,595,001.
In the preferred embodiments according to the present invention, the choice of adhesives is limited to those that are safe to use on human or animal skin, and preferably to those that are of the class known as “hypoallergenic” adhesives. The preferred acrylate copolymers are adhesives of this class.
In addition to moisture vapor permeability and hypoallergenicity, it may also be preferred that the adhesives used in connection with the adhesive composite security articles of the present invention exhibit high initial tack upon application to the skin or the surface of a nail. One such adhesive is described in commonly-assigned, co-pending U.S. Pat. No. 5,849,325, titled “Moisture-Regulated Adhesive Dressing” and other useful adhesives may include polyvinyl ether adhesives as discussed in, e.g., UK Patent No. 1280631. One advantage of an adhesive exhibiting high initial tack is additional securing of, e.g., a catheter by the dressing may be ore quickly enhanced as opposed to adhesives that have a lower initial tack.
Liners are available from a variety of manufacturers in a wide variety of proprietary formulations. Those skilled in the art will normally test those liners in simulated use conditions against an adhesive of choice to arrive at a product with the desired release characteristics. The materials used to supply the handles and liners for dressings manufactured according to the present invention is preferably substantially more rigid than the backing.
The adhesive composite dressings of the present invention may also include a low adhesion coating on a top face of the backing, which is preferably coated as a solution of polyvinyl N-octadecyl carbamate and a blend of silicone resins, as described in U.S. Pat. No. 5,531,855. While it is preferred that the top face of the adhesive composites of the present invention include a low adhesion coating, adhesive composites without such a coating are also considered to be within the scope of the present invention.
FIG. 1
is a perspective view of one embodiment of an adhesive composite dressing according to the present invention. The dressing
10
includes a backing
12
having a top and bottom face, with a pressure sensitive adhesive
14
located on the bottom face. A liner
16
is located over the adhesive
14
to protect it until delivery to a patient. The liner
16
preferably includes a liner tab
17
whose purpose will be described more completely below.
Also attached to the pressure sensitive adhesive
14
is a handle
18
useful in delivery of the dressing
10
to a patient. The handle
18
and the liner tab
17
preferably overlap each other such that they provide a convenient location to separate the liner
16
from the pressure-sensitive adhesive
14
to deliver the dressing
10
to a patient.
The backing
12
also preferably includes a first line of weakness
22
located along a first edge of the backing
12
. The line of weakness
22
is preferably provided as a line of perforations, although other lines of weakness are contemplated. The line of weakness
22
defines a portion of the backing
12
which will be referred to below as the delivery strip
20
. The handle
18
is preferably connected to the delivery strip
20
of the backing
12
such that it does not overlap the backing
12
past the location of the first line of weakness
22
.
At the opposing second edge of the backing
12
, a pair of delivery strips
24
a
and
24
b
(referred to collectively as delivery strip
24
) are defined by lines of weakness
26
a
and
26
b
located on each side of the notch
28
formed in the dressing
10
. The lines of weakness
26
a
and
26
b
will be collectively referred to as the second line of weakness
26
below.
In the illustrated embodiment of the dressing
10
, notch
28
is provided through the backing
12
, pressure-sensitive adhesive
14
, and liner
16
. The notch
28
include an opening in the second edge of the dressing
10
and extend generally towards the first edge of the dressing
10
. The notch
28
is useful in connection with ported catheters, as will be described more completely below.
FIG. 2
illustrates the delivery process in which the liner
16
has been substantially removed from contact with the pressure-sensitive adhesive
14
on the backing
12
. Although not shown, the user preferably holds the handle
18
and tab
17
of the liner
16
and separates them to suspend the backing
12
between the handle
18
and liner
16
.
Because the backing is preferably held taut between the handle
18
and liner
16
to prevent the backing
12
from folding or wrinkling after removal of the liner
16
, the bond strength between the liner
16
and the pressure-sensitive adhesive
14
in the area of the delivery strips
20
and
24
is preferably greater than the bond strength between the liner
16
and the remainder of the pressure-sensitive adhesive
14
located between the delivery strips
20
and
24
. As a result, as the user separates the liner
16
from the pressure-sensitive adhesive
14
, tension can be applied to the backing
12
as the release line between the liner
16
and pressure sensitive adhesive
14
reaches the delivery strip
24
along the second edge of the backing
12
. The result is that during delivery a user may grasp the liner
16
and the handle
18
and remove the liner
16
from a substantial portion of the backing
12
to place it in tension, thereby reducing the likelihood that the backing will fold or wrinkle during delivery.
The top face of one liner
16
is illustrated in FIG.
1
A and includes a release coating located on a release surface
15
and a retention surface
19
located along an edge of the liner
16
. It is preferred that the retention surface
19
be located along an edge of the backing
12
and, more preferably, that the retention surface correspond roughly to the delivery strip
24
of the backing
12
in size and location. To place the backing
12
in tension as described above, the bond strength between the release surface
15
and the pressure sensitive adhesive
14
is lower than the bond strength between the retention surface
19
and the pressure sensitive adhesive
14
. Similarly, the bond strength between the handle
18
and the backing
12
/pressure sensitive adhesive
14
composite is preferably greater than the bond strength between the release surface
15
and the pressure sensitive adhesive
14
.
The increased bond strength between the liner
16
and the pressure sensitive adhesive
14
in the area of the retention surface
19
can be provided through a number of techniques for disrupting the continuity of a release coating on the liner
16
. By disrupting the continuity of the release coating, the pressure sensitive adhesive
14
may be able to bond with the underlying liner
16
directly which typically results in a stranger bond as compared to the bond strength of the pressure sensitive adhesive
14
and the release coating.
In one embodiment, the increased bond between the pressure sensitive adhesive
14
and the retention surface
19
can be provided by abrading a release coating from the liner
16
to form an abraded surface in which at least a portion of the release coating, or potentially all of the release coating, is removed from the liner
16
in the area of the retention surface
19
. The amount of release coating removed by abrasion in the retention surface
19
can be varied to control the strength of the bond between the retention surface
19
and the pressure sensitive adhesive
14
.
Where smaller portions of the release coating are removed by abrasion, the bond strength may be only slightly increased, allowing the retention surface
19
to separate or release from the pressure sensitive adhesive
14
/backing
12
composite. In those embodiments, the lines of weakness
26
illustrated in connection with the dressing
10
may not be required. One advantage to such embodiments is that all of the backing
12
is delivered to the patient, with none of the backing
12
being discarded with the liner
16
after delivery.
Where larger amounts of the release coating, such as all or substantially all of the release coating, are removed from the liner
16
in the area of the retention surface
19
, the bond strength between the retention surface
19
and the pressure sensitive adhesive
14
may be too great to allow removal of the retention surface
19
from the pressure sensitive adhesive
14
without undesirable stretching of the backing
12
. In those situations, it may be preferred that a line of weakness
26
be provided in the backing
12
as illustrated to allow separation of the backing
12
before the bond between the pressure sensitive adhesive
14
and a patient's skin is compromised by stretching of the backing
12
during removal of the liner
16
.
Where a line of weakness
26
is provided in the backing
12
, the bond strength between the retention surface
19
of the liner
16
and the pressure sensitive adhesive
14
in the area of the delivery strip
24
is preferably greater than the tensile strength of the backing
12
across the line of weakness
26
. As a result, after proper location of the dressing
10
on a patient's skin such that the exposed pressure-sensitive adhesive
14
is adhered to the skin, the backing
12
can be smoothed down and increased tension is applied to the backing
12
by pulling the liner
16
away from the backing
12
. The increased tension preferably causes the film backing
12
to separate along line of weakness
26
. After separation, the delivery strip
24
is removed from the backing
12
along with liner
16
, without separation of the retention surface
19
of the liner
16
from the delivery strip
24
.
In those dressings in which it is desired that the handle
18
be separable from the remainder of the dressing
10
after delivery and in which the handle
18
is attached to the pressure sensitive adhesive
14
on the backing
12
, the bond strength between the handle
18
and the pressure-sensitive adhesive
14
may also be controlled through abrasion of a release coating on the handle as described with respect to the liner
16
above. In other words, the bond between the handle
18
and the pressure sensitive adhesive
14
can be controlled to allow removal of the handle
18
from the pressure sensitive adhesive
14
without significantly stretching the backing
12
to the point at which the bond between the pressure sensitive adhesive and the patient's skin is unacceptably compromised. In such embodiments where the bond between the handle
18
and the pressure sensitive adhesive
14
is releasable, no line of weakness is required and none of the backing
12
is removed with the handle
18
.
In other embodiments such as the one depicted in
FIGS. 1 and 2
, the handle
18
is not releasably attached to the pressure sensitive adhesive
14
and a line of weakness
22
is provided. In such an embodiment, the handle
18
may include an abraded surface from which substantially all of a release coating has been removed from the handle
18
. The backing
12
preferably separates preferably separates along the line of weakness
22
during removal of the handle
18
because the strength of the bond between the handle
18
and the pressure sensitive adhesive
14
is greater than the tensile strength of the backing
12
across the line of weakness
22
. As a result, removal of the handle
18
also removes the delivery strip
20
portion of the backing
12
along the line of weakness
22
.
The lines of weakness
22
and
26
in the illustrated embodiment of dressing
10
may be provided in the form of perforations. The dimensions of the perforations vary based on the backing
12
and other factors, although too few perforations or perforations that are too small can result in stretching, deformation and uneven weakness of the backing
12
. At the other end of the spectrum, too many perforations or perforations that are too large can result in backings
12
that separate too easily, thereby inhibiting the tension that can be applied to the backing
12
between the handle
18
and liner
16
. The result is that smooth delivery of the backing
12
can be inhibited.
Although the liner
16
and handle
18
have been described as including abraded surfaces from which a portion or all of a release coating has been removed, the dressings according to the present invention may alternatively be manufactured with embossed liners
16
and handles
18
to increase the strength of the bond between the pressure sensitive adhesive
14
and the liner
16
and/or handle
18
.
Embossing a release coated surface can increase the bond strength between that surface and a pressure sensitive adhesive by disrupting the continuity of the release coating in the embossed areas. That discontinuous release coating increases bond strength by allowing tie pressure sensitive adhesive
14
access the materials underneath the release coating. For example, a liner
16
could include a retention surface
19
that is embossed instead of, or in addition to, abrading as discussed above. The exact nature of the embossing used in the retention surface
19
can vary based on, e.g., the pressure sensitive adhesive
14
, the release coating, the liner material, whether the dressing is gamma sterilized (which can increase the bond strengths), etc.
The embossed retention surface
19
could be releasably attached to the pressure sensitive adhesive
14
in which case no line of weakness
26
is required to allow removal of the liner
16
from the dressing
10
. Alternatively, the embossing could cause enough disruption in the release coating such that a line of weakness
26
would be desirable to prevent excessive stretching of the backing
12
when removing the liner
16
.
The handle
18
could include an embossed surface similar to that used in connection with the liner
16
to achieve either a desired releasable handle
18
or a handle
18
that is more securely attached to the backing
12
, thereby requiring a line weakness
22
along which the backing
12
separates during removal of the handle
18
.
FIG. 3
illustrates the backing
12
of
FIGS. 1 and 2
in place over a catheter
30
after the release liner
16
and the handle
18
have been removed. The edges
23
,
27
a,
and
27
b
of the backing
12
are formed along the lines of weakness
22
and
26
, as described above. The backing
12
is preferably sized to assure that the insertion site
31
of the catheter
30
is covered by the backing
12
and pressure-sensitive adhesive
14
. It is further preferred that the backing
12
and pressure-sensitive adhesive
14
offer adequate support to the wings
34
of the catheter
30
. The notch
28
, formed in the second edge of the backing
12
, is positioned over the catheter hub
32
and allows connection of the extension tubing set
36
to the catheter
30
as desired.
Returning to
FIG. 2
, the notch
28
formed through the backing
12
, pressure-sensitive adhesive
14
, and liner
16
preferably opens into a void defined by a backing notch
28
a
and a liner notch
28
b.
It is preferred that the larger opening formed during delivery of the dressing
10
assists in its placement over a catheter
30
, as depicted in FIG.
3
. Furthermore, it is advantageous that the backing
12
is supported on both sides of the notch
28
a
by the unitary liner
16
to reduce the likelihood of wrinkling or folding of the backing
12
in the area around the notch
28
a.
It will be understood that although the notch
28
formed in the dressing
10
includes a liner notch
28
b,
it may be possible in some instances to remove only the backing and pressure-sensitive adhesive in the area of the notch
28
while leaving substantially all of the liner
16
in place.
FIGS. 4 and 5
illustrate an alternative embodiment of the adhesive composite dressings according to the present invention. One variation in the dressing
110
is that the handle
118
is attached to the top face of the backing
112
, i.e., on the opposite face on which the pressure sensitive adhesive
114
is located. The handle
118
preferably extends beyond the edge
113
of the backing
112
as best seen in FIG.
4
. Another variation is that the dressing
110
does not include a notch designed to adapt the dressing
110
for placement over a catheter or other device.
As with the dressing
10
described in connection with
FIGS. 1 and 2
, it is preferred that the bond strength between the handle
118
and the backing
112
preferably be stronger than the bond strength between the release surface of the liner
116
and the pressure-sensitive adhesive
114
. As a result, a user can grasp the handle
118
and the tab portion
117
of the liner
116
to separate the release surface of the liner
116
from the pressure-sensitive adhesive
114
and backing
112
.
The bond strength between the release surface of the liner
116
and the pressure-sensitive adhesive
114
along the edge of the backing
112
is greater than the bond strength between the release surface of the liner
116
and the pressure-sensitive adhesive
114
over the remainder of the backing
112
. As a result, a user can deliver the backing
112
and pressure-sensitive adhesive
114
by holding the backing
112
taut between the handle
118
and the liner
116
in a manner similar to that discussed above with respect to dressing
10
.
In those dressings in which a line of weakness
126
is provided in the backing
112
, it may be preferred that the bond strength between the liner
116
and the pressure-sensitive adhesive
114
along the edge of the backing
112
(generally corresponding to the area of the delivery strip
124
) be greater than the tensile strength of the backing
112
across the line of weakness
126
. As a result, after application of the backing
112
and pressure-sensitive adhesive
114
to the skin of a patient, the liner
116
can be removed by separating the backing
112
along the line of weakness
126
. At the opposite edge of the backing
112
, it is also preferred that the handle
118
be removable from the backing
112
. The handle
118
may be removed by using a line of weakness or by releasably bonding the handle
118
to the pressure sensitive adhesive
114
as described in connection with dressing
10
above.
A removable handle
118
may alternatively be attached to the backing
112
using a releasable heat seal bond. Such releasable heat seal bonds are described in, e.g., U.S. Pat. No. 5,738,642 (Heinecke et al.). Briefly, however, any releasable heat seal bond should be secure, yet releasable, i.e., the handle
118
and backing
112
can be separated without destroying the integrity of the backing
112
or the bond between the pressure sensitive adhesive
114
on the backing
112
and the skin of a patient. That is, the bond strength between the handle
118
and the backing
112
is lower than the bond strength between the adhesive
114
and the skin of a patient. In addition, the bond between the handle
118
and the backing
112
should be stronger than the bond between the adhesive
114
and the liner
116
to facilitate separation of the liner
116
from the pressure sensitive adhesive
114
during delivery.
FIG. 6
illustrates another dressing
210
according to present invention that includes a backing
212
and pressure sensitive adhesive
214
. Although optional, the illustrated dressing
210
includes a notch
228
opening along the first edge
223
of the backing
212
. The notch
228
is preferably adapted to fit over a catheter or other similar medical device.
The pressure sensitive adhesive
214
is protected before delivery by a two-part liner including liner sheets
216
a
and
216
b.
The two liner sheets
216
a
and
216
b
are preferably, but not necessarily provided with a J-fold to assist a user in grasping the liner sheets
216
a
and
216
b
to deliver the dressing
210
. It is further preferred that the liner sheet
216
a,
through which the notch
228
is formed, extend towards the opposite edge
221
of the backing
212
far enough to contain the entire notch
228
. In other words, the apex of the notch
228
is preferably formed in the liner sheet
216
a.
The liner sheet
216
a
includes a release surface
215
a
in contact with a portion of the pressure sensitive adhesive
214
on backing
212
and a first retention surface
219
a
in contact with the pressure sensitive adhesive
214
near the edge
223
of the backing
212
. The strength of the bond between the pressure sensitive adhesive
214
and the retention surface
219
a
is greater than the strength of the bond between the pressure sensitive adhesive
214
and the release surface
215
a.
The retention surface
219
a
can be formed by, e.g., abrasion, embossing, abrasion and embossing, etc. in which the release coating on the liner sheet
216
a
is disrupted.
The backing
212
may include a line of weakness
226
if the bond between the retention surface
219
a
and pressure sensitive adhesive
214
is not releasable without excessive stretching of the backing
212
. The line of weakness
226
and the first edge
223
of the backing
212
define a delivery strip
224
as illustrated in the drawing. It is preferred that the retention surface
219
a
be located substantially within the area of the delivery strip
224
, if provided.
The liner sheet
216
b
is constructed similar to the liner sheet
216
a
above and includes a release surface
215
b
and retention surface
219
b
in contact with the pressure sensitive adhesive
214
near the edge
221
of the backing
212
. The illustrated backing
212
also includes an optional line of weakness
222
defining a delivery strip
220
. The details regarding the construction of that side of the dressing
210
are the same as those described with respect to the side of the dressing including liner
216
a
above.
Because of the differential bonding strengths between the release surfaces
215
a
/
215
b
and the retention surfaces
219
a
/
219
b,
the backing
212
of the dressing
210
can be delivered in a manner similar to that illustrated in FIG.
2
. In other words, the user can grasp both liner sheets
216
a
and
216
b
and pull them in opposite directions until the lines of release between the pressure sensitive adhesive
214
and the liner sheets
216
a
and
216
b
reach the retention surfaces
219
a
and
219
b.
At that point the backing
212
can be held taut between the two liner sheets
216
a
and
216
b,
with the pressure sensitive adhesive
214
adhered to the retention surfaces
219
a
and
219
b.
The dressing can then be placed in a desired location and the backing
212
smoothed down to adhere the exposed pressure sensitive adhesive
214
to the patient's skin.
After location of the backing
212
on a patient, the retention surfaces
219
a
and
219
b
can be separated from the pressure sensitive adhesive
214
. In dressings in which the bond between the retention surfaces
219
a
and
219
b
is higher, the backing
212
can be separated along the lines of weakness
222
and
226
by placing further tension on the backing
212
using the liner sheets
216
a
and
216
b.
In those dressings, the tensile strength of the backing
212
across the lines of weakness
222
and
226
is preferably less than the strength of the bond between the pressure sensitive adhesive
214
and the respective retention surface
219
a
or
219
b.
As a result, increasing the tension in the backing
212
using the liner sheets
216
a
and
216
b
typically causes separation of the backing
212
along the corresponding lines of weakness
222
and
226
. That separation further results in removal of the corresponding delivery strips (
220
and/or
224
) from the remainder of the backing
212
.
FIG. 7
illustrates another dressing
310
according to present invention that includes a backing
312
and pressure sensitive adhesive
314
. Although optional, the illustrated dressing
310
includes a notch
328
opening along the first edge
323
of the backing
312
. The notch
328
is preferably adapted to fit over a catheter or other similar medical device.
The pressure sensitive adhesive
314
is protected before delivery by a two-part liner including liner sheets
316
a
and
316
b.
The two liner sheets
316
a
and
316
b
are preferably, but not necessarily provided with a J-fold to assist a user in grasping the liner sheets
316
a
and
316
b
to deliver the dressing
310
. It is further preferred that the liner sheet
316
a,
through which the notch
328
is formed, extend towards the opposite edge
321
of the backing
312
far enough to contain the entire notch
328
. In other words, the apex of the notch
328
is preferably formed in the liner sheet
316
a.
The liner sheet
316
a
includes a release surface
315
a
in contact with a portion of the pressure sensitive adhesive
314
on backing
312
and at least one void
340
a
formed completely through the liner sheet
316
a.
As illustrated in
FIG. 7
, it is preferred that a plurality of voids
340
a
be formed along the edge of the liner sheet
316
a
proximate the edge
321
of the backing
312
. It is further preferred that, where a line of weakness
322
is provided in the backing
312
, all of the voids
340
a
be located within the delivery strip
320
defined by the line of weakness
322
and the edge
321
of the backing
312
.
A retainer
342
a
can be located over the voids
340
a
in the liner sheet
316
a
such that the portions of the pressure sensitive adhesive
314
exposed by the voids
340
a
bond with the portions of the retainer
342
a
located over the voids
340
a.
The strength of the bond between the pressure sensitive adhesive
314
and the retainer
340
a
is greater than the strength of the bond between the pressure sensitive adhesive
314
and the release surface
315
a
on the liner sheet
316
a.
It is preferred, but not required, that the retainer
342
a
also be bonded to the liner sheet
316
a
(on the opposite face from the release surface
315
a
). It may be further preferred that the retainer
342
a
itself include a pressure sensitive adhesive on the surface facing the liner sheet
316
a
to bond the retainer
342
a
to the liner sheet
316
a.
That additional adhesive on the retainer
342
a
may also enhance the bond between the retainer
342
a
and the pressure sensitive adhesive
314
on the backing.
The opposing edge
323
of the backing
312
includes a similar construction including voids
340
b
formed in the other liner sheet
316
b
and a retainer
342
b
bonded to the pressure sensitive adhesive
314
exposed within the voids
340
b.
Although not explicitly illustrated in
FIG. 7
, it will be understood that voids
340
b
are formed on each side of the notch
328
along the edge
323
of the dressing
310
. It is further preferred that, where a line of weakness
326
is located proximate the edge
323
, the voids
340
b
be located within the delivery strip
324
defined by the line of weakness
326
and the edge
323
of the backing
312
.
As along edge
321
of the backing
312
, the strength of the bond between the pressure sensitive adhesive
314
and the retainer
340
b
is greater than the strength of the bond between the pressure sensitive adhesive
314
and the release surface
315
b
on the liner sheet
316
b.
It is preferred, but not required, that the retainer
342
b
also be bonded to the liner sheet
316
b
(on the opposite face from the release surface
315
b
).
It may be further preferred that the retainer
342
b
itself include a pressure sensitive adhesive on the surface facing the liner sheet
316
b
to bond the retainer
342
b
to the liner sheet
316
b.
That additional adhesive on the retainer
342
b
may also enhance the bond between the retainer
342
b
and the pressure sensitive adhesive
314
on the backing
312
.
Because of the differential bonding strengths between the release surfaces
315
a
/
315
b
and the retainers
342
a
/
342
b,
the backing
312
of the dressing
310
can be delivered in a manner similar to that illustrated in FIG.
2
. In other words, the user can grasp both liner sheets
316
a
and
316
b
and pull them in opposite directions until the lines of release between the pressure sensitive adhesive
314
and the liner sheets
316
a
and
316
b
reach the voids
340
a
and
340
b.
At that point the backing
312
can be held taut between the two liner sheets
316
a
and
316
b,
with the pressure sensitive adhesive
314
adhered to the retainers
342
a
and
342
b
through the voids
340
a
and
340
b
in the liners sheets
316
a
and
316
b.
The dressing can then be placed in a desired location and the backing
312
located between the lines of weakness
322
and
326
smoothed down to adhere the exposed pressure sensitive adhesive
314
.
After location of the backing
312
on a patient, the liner sheets
316
a
and
316
b
and the retainers
342
a
and
342
b
can be separated from the pressure sensitive adhesive
314
. In dressings in which the bond between the retainers
342
a
and
342
b
is higher, the backing
312
is preferably separated along the lines of weakness
322
and
326
by placing further tension on the backing
312
using the liner sheets
316
a
and
316
b.
In this embodiment, the tensile strength of the backing
312
across the lines of weakness
322
and
326
is preferably less than the strength of the bond between the pressure sensitive adhesive
314
and the respective retainers
342
a
or
342
b
through the respective voids
340
a
or
340
b.
As a result, increasing the tension in the backing
312
using the liner sheets
316
a
and
316
b
typically causes separation of the backing
312
along the corresponding lines of weakness
322
and
326
.
In a further variation, the dressing
310
could be provided without the retainers
342
a
and
342
b
placed over the voids
340
a
and
340
b.
Increased bond strength is obtained in those dressings at the areas around the voids
340
a
and
340
b
by interaction of the pressure sensitive adhesive
314
with the edges of the voids. As discussed above, the lines of weakness
322
and
326
are optional depending on the strength of the bonds between the liner sheets
316
a
and
316
b
at the edges of the backing
312
.
In some respects, the voids
340
a
and
340
b
provided in liner sheets
316
a
and
316
b
(and retainers
342
a
and
342
b,
if present) define retention surfaces as discussed above with respect to the abraded and embossed liners and handles discussed above. Like the retention surfaces discussed above, the retention surfaces defined by the voids
340
a
and
340
b
provide increased bonding to the pressure sensitive adhesive
314
as compared to the strength of the bonds between the release surfaces
315
a
and
315
b.
In one respect, the voids
340
a
and
340
b
can be thought of as disrupting the continuity of the release coating, resulting in a retention surface having a discontinuous release coating that contributes to increased adhesion between the liner sheets and the pressure sensitive adhesive in the area of the voids.
All of the dressings described above include optional notches formed therein to assist in placement of the dressings over a catheter insertion site. All of the notches in the dressings open on an edge of the dressing along which the bond strength between the pressure sensitive adhesive on the backing and the liner or retainer is increased as compared to the strength of the bond between the pressure sensitive adhesive and the remainder of the liner. In some of the embodiments described above, the means for increasing the bond strength between the liner and the pressure sensitive adhesive proximate the edge is an abraded liner surface. In other embodiments, the means for increasing the bond strength takes the form of one or more voids in the liner, through which a retainer is adhered to the pressure sensitive adhesive. The retainer serves to effectively increase the strength of the bond between the liner and pressure sensitive adhesive by interfering with removal of the liner from the pressure sensitive adhesive in the area around the void or voids.
Although two illustrative examples of means for increasing the bond strength between the pressure sensitive adhesive and the liner are provided herein, when used in connection with a notched dressing, the present invention may also rely on other techniques of increasing the bond strength between a pressure sensitive adhesive on a backing and a liner. Examples of other suitable techniques include those described in, e.g., U.S. Pat. Nos. Re. 33,353 (Heinecke); U.S. Pat. No. 4,513,739 (Johns); U.S. Pat. No. 5,153,040 (Faasse, Jr.); and U.S. Pat. No. 5,520,629 (Heinecke et al.).
Any technique that results in increased bond strength between a liner and a backing/pressure sensitive adhesive composite along an edge that includes a notch opening can provide the advantage of assisting in the placement of the dressing over a catheter insertion site. The dressings provide that advantage by allowing the user to maintain tension on both portions of the backing that flank the notch formed therein. By maintaining tension on those backing portions, smooth, aseptic delivery of the dressing is enhanced. The specific techniques of increasing bond strength using abraded liner surfaces, embossed liners, and/or liner voids can, however, provide additional advantages as compared to those techniques of increasing bond strength as discussed in the patents listed above.
For example, the techniques of increasing bond strength as specifically discussed herein (abrasion/embossing/perforating) provide advantages in terms of manufacturing cost and simplicity by allowing the dressings to be manufactured with a single liner material having a release coating over one entire surface, thereby reducing inventory requirements. Furthermore, the operations (abrasion, embossing, perforating, etc.) used to disrupt the continuity of the release coating on the liner can typically be performed in-line with other converting processes, further simplifying manufacturing and reducing cost.
FIG. 8
is a schematic diagram of one method of manufacturing adhesive composite dressings
80
according to the present invention. The method and system depicted in
FIG. 8
include a supply of liner
50
, including a release surface
52
. The liner
50
is preferably directed into a station
61
where a portion of the release surface
52
of the liner
50
is abraded and/or embossed to disrupt the release coating. If the liner
50
is abraded, it is preferred that the station
61
also include an enclosure
66
in which a vacuum is provided to remove debris generated by the abrasion process. After the liner
50
has been abraded and/or embossed, it is directed into a nip roll station
76
along with a supply of backing
70
including a pressure-sensitive adhesive
72
on one surface thereof and a handle material supply
74
. The resulting composite, which includes a release liner, pressure-sensitive adhesive, handle, and backing, is then directed into a sheeting station
78
where individual adhesive composite dressings
80
are sheeted from the web. The sheeting station
78
may also be used to form notches in the dressings
80
if so desired. Alternatively, the notches may be formed after lamination of the liner
50
and backing
70
and before sheeting if so desired.
FIG. 9
is a diagram of one particular abrasion process useful in producing adhesive composite dressings according to the present invention. The depicted process involves directing a release liner
50
having a release surface
52
into a nip formed by a pair of abrasion rolls
56
rotating in direction
48
. The abrasion rolls
56
are preferably forced against a backing roll
60
that is rotating in the direction
54
in which the liner
50
is moving. The composition of the abrasion rolls
56
can vary, although it is preferred that they have a sufficiently rough surface to remove the release coating
52
on the liner
50
. Examples of suitable abrasion rolls
56
can be manufactured from abrasive materials such as those marketed under the tradename SCOTCHBRITE™ Paint & Varnish Remover (Catalog No. 9414NA) by Minnesota Mining and Manufacturing Company, St. Paul, Minn.
As a result of the operation of the abrasion rolls
56
on the liner
50
, a central area
64
of the liner
50
remains coated with the release coating while the release coating in areas
62
on each edge of the release liner
50
is at least partially removed. After abrading, the liner
50
can be slit along the machine direction to supply either a handle and liner sheet combination as depicted in, for example,
FIG. 1
or the liner
50
can be slit along the machine direction and folded to form a two-part liner as illustrated in, for example, FIG.
6
.
If embossing is used in place of abrasion, the edges of the liner
50
can be embossed in a manner similar to that depicted in the abrasion process illustrated in FIG.
9
. As discussed above, the embossing disrupts continuity of the release coating on the liner to increase adhesion to the pressure sensitive adhesive on the backing film. It may be advantageous to beat one or both rolls used in embossing to assist in disrupting the release coating.
FIG. 10
is a schematic diagram of another method of manufacturing adhesive composite dressings
380
according to the present invention. The method and system depicted in
FIG. 10
include a supply of liner
350
including a release surface
352
. The liner
350
is preferably directed into a station
360
where a series of voids can be formed in the liner
350
. After the liner
350
has been perforated, it is directed into a slitting station
368
where the liner
350
can be slit along the machine direction and a J-fold formed in one side of the slit liner
350
. After slitting and folding, the liner
350
is directed into a nip roll station
376
along with a supply of backing
370
including a pressure-sensitive adhesive
372
on one surface thereof and a supply of retainer material
377
. The resulting composite, which includes a backing, pressure sensitive adhesive, release liner, and retainers, is then directed into a sheeting station
378
where individual adhesive composite dressings
380
are sheeted from the web.
FIG. 11
illustrates one process of forming voids
440
in a continuous web of liner
416
using two perforating nip stations
444
. Each of the perforating nip stations
444
includes a male and female die roll
446
and
448
, respectively, that mesh to form the desired voids in the liner
416
. Other methods of forming voids in sheet material will be known to those skilled and the art and may be substituted for the illustrated apparatus and method.
Although various illustrative embodiments of dressings and methods of manufacturing the same have been described above, it should be understood that additional variations are possible. As one example, additional components may be added to the dressings, such as the catheter support strips discussed in U.S. Pat. No. 5,520,629. Furthermore, although the dressings illustrated above are generally rectangular in shape, dressings according to the present invention may be manufactured with any desired shape.
The patents, patent documents, and publications cited herein are incorporated by reference in their entirety, as if each were individually incorporated by reference. Various modifications and alterations of this invention, other than those explicitly discussed above, will become apparent to those skilled in the art without departing from the scope of this invention, and it should be understood that this invention is not to be unduly limited to the illustrative embodiments set forth herein.
Claims
- 1. An adhesive composite dressing comprising:a backing having top and bottom faces and opposing first and second edges; a pressure sensitive adhesive located on the bottom face of the backing; a liner comprising a release surface and a retention surface, the retention surface including a discontinuous release coating that is embossed, wherein the retention surface is attached to the pressure sensitive adhesive along the first edge of the backing; and a handle attached to the backing along the second edge of the backing.
- 2. A dressing according to claim 1, further comprising a notch formed in the backing, pressure sensitive adhesive, and liner, wherein the notch opens along the first edge of the backing and extends towards the second edge of the backing.
- 3. An adhesive composite dressing comprising:a backing having top and bottom faces and opposing first and second edges; a pressure sensitive adhesive located on the bottom face of the backing; a first liner sheet including a first release surface attached to a portion of the pressure sensitive adhesive and a first retention surface including a discontinuous release coating that is embossed, the first retention surface being attached to the pressure sensitive adhesive along the first edge of the backing, wherein the strength of the bond between the first retention surface and the pressure sensitive adhesive is greater than the strength of the bond between the first release surface and the pressure sensitive adhesive; and a second liner sheet including a second release surface attached to a portion of the pressure sensitive adhesive and a second retention surface including a discontinuous release coating that is embossed, the second retention surface being attached to the pressure sensitive adhesive along the second edge of the backing, wherein the strength of the bond between the second retention surface and the pressure sensitive adhesive is greater than the strength of the bond between the second release surface and the pressure sensitive adhesive.
- 4. An adhesive composite dressing comprising:a backing having top and bottom faces and opposing first and second edges; a pressure sensitive adhesive located on the bottom face of the backing; a liner including a release surface attached to the pressure sensitive adhesive and a void formed through the liner, the void exposing a portion of the pressure sensitive adhesive, wherein the bond strength between the liner and the pressure sensitive adhesive is increased proximate the void.
- 5. A dressing according to claim 4, further comprising a retainer attached to the exposed portion of the pressure sensitive adhesive through the void in the liner, wherein the strength of the bond between the retainer and the pressure sensitive adhesive is greater than the strength of the bond between the release surface and the pressure sensitive adhesive.
- 6. A dressing according to claim 5, wherein the retainer is attached to the liner.
- 7. An adhesive composite dressing comprising:a backing having top and bottom faces and opposing first and second edges; a pressure sensitive adhesive located on the bottom face of the backing; a first liner sheet including a first release surface attached to a portion of the pressure sensitive adhesive and a first void exposing a first portion of the pressure sensitive adhesive; and a second liner sheet including a second release surface attached to a portion of the pressure sensitive adhesive and a second void exposing a portion of the pressure sensitive adhesive.
- 8. A dressing according to claim 7, further comprising:a first retainer attached to the portion of the pressure sensitive adhesive exposed through the first void in the first liner sheet, wherein the strength of the bond between the first retainer and the pressure sensitive adhesive is greater than the strength of the bond between the first release surface and the pressure sensitive adhesive; and a second retainer attached to the portion of the pressure sensitive adhesive exposed through the second void in the second liner sheet, wherein the strength of the bond between the second retainer and the pressure sensitive adhesive is greater than the strength of the bond between the second release surface and the pressure sensitive adhesive.
- 9. A dressing according to claim 8, wherein the first retainer is attached to the first liner sheet and the second retainer is attached to the second liner sheet.
- 10. A dressing according to claim 1, wherein the handle is removably attached to the top face of the backing.
- 11. A dressing according to claim 1, further comprising a first line of weakness in the backing proximate the first edge of the backing.
- 12. A dressing according claim 11, wherein the tensile strength of the backing across the first line of weakness is less than the strength of the bond between the pressure sensitive adhesive and the retention surface on the liner.
- 13. A dressing according to claim 1, wherein the handle includes an abraded surface, and further wherein the abraded surface of the handle is attached to the pressure sensitive adhesive along the second edge of the backing.
- 14. A dressing according to claim 1, further comprising a second line of weakness in the backing proximate the second edge of the backing.
- 15. A dressing according to claim 3, further comprising a first line of weakness in the backing proximate the first edge of the backing and a second line of weakness proximate the second edge of the backing.
- 16. A dressing according claim 15, wherein the tensile strength of the backing across the first line of weakness is less than the strength of the bond between the pressure sensitive adhesive and the first retention surface on the first liner sheet; and wherein the tensile strength of the backing across the second line of weakness is less than the strength of the bond between the pressure sensitive adhesive and the second retention surface on the second liner sheet.
- 17. An adhesive composite dressing comprising:a backing having top and bottom faces and opposing first and second edges; a pressure sensitive adhesive located on the bottom face of the backing; a liner comprising a release surface and a retention surface, the retention surface including a discontinuous release coating that is abraded, wherein the retention surface is attached to the pressure sensitive adhesive along the first edge of the backing; and a handle attached to the backing along the second edge of the backing.
- 18. A dressing according to claim 17, further comprising a notch formed in the backing, pressure sensitive adhesive, and liner, wherein the notch opens along the first edge of the backing and extends towards the second edge of the backing.
- 19. A dressing according to claim 17, wherein the handle is removably attached to the top face of the backing.
- 20. A dressing according to claim 17, further comprising a first line of weakness in the backing proximate the first edge of the backing.
- 21. A dressing according to claim 20, wherein the tensile strength of the backing across the first line of weakness is less than the strength of the bond between the pressure sensitive adhesive and the retention surface on the liner.
- 22. A dressing according to claim 17, wherein the handle includes an abraded surface, and further wherein the abraded surface of the handle is attached to the pressure sensitive adhesive along the second edge of the backing.
- 23. A dressing according to claim 17, further comprising a second line of weakness in the backing proximate the second edge of the backing.
- 24. An adhesive composite dressing comprising:a backing having top and bottom faces and opposing first and second edges; a pressure sensitive adhesive located on the bottom face of the backing; a first liner sheet including a first release surface attached to a portion of the pressure sensitive adhesive and a first retention surface including a discontinuous release coating that is abraded, the first retention surface being attached to the pressure sensitive adhesive along the first edge of the backing, wherein the strength of the bond between the first retention surface and the pressure sensitive adhesive is greater than the strength of the bond between the first release surface and the pressure sensitive adhesive; and a second liner sheet including a second release surface attached to a portion of the pressure sensitive adhesive and a second retention surface including a discontinuous release coating that is abraded, the second retention surface being attached to the pressure sensitive adhesive along the second edge of the backing, wherein the strength of the bond between the second retention surface and the pressure sensitive adhesive is greater than the strength of the bond between the second release surface and the pressure sensitive adhesive.
- 25. A dressing according to claim 24, further comprising a first line of weakness in the backing proximate the first edge of the backing and a second line of weakness proximate the second edge of the backing.
- 26. A dressing according to claim 25, wherein the tensile strength of the backing across the first line of weakness is less than the strength of the bond between the pressure sensitive adhesive and the first retention surface on the first liner sheet; and wherein the tensile strength of the backing across the second line of weakness is less than the strength of the bond between the pressure sensitive adhesive and the second retention surface on the second liner sheet.
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Number |
Date |
Country |
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EP |
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0 051 935 |
May 1982 |
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0 437 944 |
Jul 1991 |
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1280631 |
Jul 1972 |
GB |
WO 9829516 |
Jul 1998 |
WO |