Surgical dressing with delivery system and method of manufacture

Information

  • Patent Grant
  • 6607799
  • Patent Number
    6,607,799
  • Date Filed
    Thursday, October 15, 1998
    25 years ago
  • Date Issued
    Tuesday, August 19, 2003
    21 years ago
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.
US Referenced Citations (34)
Number Name Date Kind
2532011 Dahlquist et al. Nov 1950 A
RE24906 Ulrich Dec 1960 E
3389827 Abere et al. Jun 1968 A
3645835 Hodgson Feb 1972 A
4112213 Waldman Sep 1978 A
4310509 Berglund et al. Jan 1982 A
4323557 Rosso et al. Apr 1982 A
4472480 Olson Sep 1984 A
4513739 Johns Apr 1985 A
4545371 Grossmann et al. Oct 1985 A
4595001 Potter et al. Jun 1986 A
4598004 Heinecke Jul 1986 A
4726972 Instance Feb 1988 A
4737410 Kantner Apr 1988 A
4753232 Ward Jun 1988 A
4832008 Gilman May 1989 A
4884563 Sessions Dec 1989 A
4926850 Lott et al. May 1990 A
4941882 Ward et al. Jul 1990 A
RE33353 Heinecke Sep 1990 E
5088483 Heinecke Feb 1992 A
5153040 Faasse, Jr. Oct 1992 A
5160315 Heinecke et al. Nov 1992 A
5266371 Sugii et al. Nov 1993 A
5411295 Bates et al. May 1995 A
5520629 Heinecke et al. May 1996 A
5531855 Heinecke et al. Jul 1996 A
5722943 Sessions Mar 1998 A
5733251 Johns Mar 1998 A
5738642 Heinecke et al. Apr 1998 A
5849325 Heinecke et al. Dec 1998 A
5951505 Gilman et al. Sep 1999 A
5968000 Harrison et al. Oct 1999 A
6197397 Sher et al. Mar 2001 B1
Foreign Referenced Citations (8)
Number Date Country
0 035 399 Sep 1981 EP
0 035 399 Sep 1981 EP
0 051 935 May 1982 EP
0 051 935 May 1982 EP
0 437 944 Jul 1991 EP
0 437 944 Jul 1991 EP
1280631 Jul 1972 GB
WO 9829516 Jul 1998 WO