Patent Application
20200397984
The present invention relates generally to medical devices and to methods for making such devices. In particular, but not by way of limitation, the present invention relates to an infusion set, patch pump or other on-body medical device having an adhesive patch that is secured to the medical device during manufacture of the medical device or during manufacture of a portion of the medical device.
In the management of diabetes, insulin can be administered to a user on a continuous basis using a programmable infusion pump. The pump is small, portable and battery-operated, and can be worn or carried inconspicuously by the user. The pump is attached by a length of tubing to an infusion set, which is a disposable body-worn device having a skin-adhering base, a fluid connector, and a rigid needle or flexible catheter that conducts the insulin into the subcutaneous or intradermal layer of the user's skin. A flexible adhesive patch or pad on the bottom of the infusion set base allows for temporary skin attachment during the period (typically a few days) that the infusion set remains in place before it is removed and replaced for sanitary reasons.
Another type of insulin infusion device, known as a patch pump, has also come into use. Unlike a conventional infusion pump, a patch pump is an integrated device that combines most or all of the required components in a single housing and does not require the use of a separate infusion set or connecting tubing. A patch pump adheres directly to the skin, contains insulin in an internal reservoir, and delivers the insulin via an integrated subcutaneous catheter. As in the case of an infusion set, a patch pump typically includes a flexible adhesive patch on its bottom surface to allow for temporary skin attachment at the infusion site.
The flexible adhesive patch is typically made of a thin fibrous material, similar to a medical dressing, but with adhesive layers on both sides. On the skin contact side, an adhesive suitable for medical or surgical use is provided, and is covered by a removable backing layer or release liner made of silicone-coated kraft paper. The release liner is removed by the user before attaching the infusion set or patch pump to the skin. The skin contact adhesive must be sufficiently strong to secure the infusion set or patch pump to the skin, but must also allow for removal of the device without damaging the skin. On the device side, a different adhesive is used, one which provides for permanent attachment between the patch and the base of the infusion set or patch pump.
Some infusion sets and/or patch pumps employ a flexible material, such as thermoplastic polyurethane (TPU), for at least a part of the device to provide greater freedom of movement to the patient or to better conform to curves of a patient's body. Unfortunately, TPU and some other flexible materials sometimes have difficulty adhering to adhesive patches or pads using only an adhesive. In addition, the manufacturing process for the infusion set or patch pump may require that the adhesive patch be dispensed from a continuous roll for handling by automated equipment. This may impose additional requirements on the types of adhesives that can be used.
Accordingly, it is an aspect of the present invention to provide a medical device having a secured adhesive patch and a method of manufacturing such a medical device.
The foregoing and/or other aspects of the present invention are achieved by providing an on-body medical device, including a flexible base portion having one or more through-holes therein, an adhesive patch, the flexible base portion being disposed on a non-patient side of the adhesive patch with the through-holes in communication with the adhesive patch, and an adhesive plug cured in the one or more through-holes on the adhesive patch and walls of the flexible base portion laterally surrounding the one or more through-holes, the adhesive plug mechanically bonding the flexible base portion to the adhesive patch.
The foregoing and/or other aspects of the present invention are also achieved by providing a method of manufacturing a medical device, including forming a flexible base portion to have a plurality of through-holes therethrough, placing the flexible base portion on a non-patient side of an adhesive patch with the through-holes in communication with the adhesive patch, dispensing an adhesive into the through-holes onto the adhesive patch and walls of the flexible base portion surrounding the through-holes; and curing the adhesive to form an adhesive plug mechanically bonding the flexible base portion to the adhesive patch.
Additional and/or other aspects and advantages of the present invention will be set forth in the description that follows, or will be apparent from the description, or may be learned by practice of the invention.
The above and/or other aspects and advantages of embodiments of the invention will be more readily appreciated from the following detailed description, taken in conjunction with the accompanying drawings, in which:
Reference will now be made in detail to embodiments of the present invention, which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. The embodiments described herein exemplify, but do not limit, the present invention by referring to the drawings.
It will be understood by one skilled in the art that this disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the drawings. The embodiments herein are capable of other embodiments, and capable of being practiced or carried out in various ways. Phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless limited otherwise, the terms “connected,” “coupled,” and “mounted,” and variations thereof herein are used broadly and encompass direct and indirect connections, couplings, and mountings. In addition, the terms “connected” and “coupled”” and variations thereof are not restricted to physical or mechanical connections or couplings. Further, terms such as “up,” “down,” “bottom,” “top,” “front,” “rear,” “upper,” “lower,” “upwardly,” “downwardly,” and other orientational descriptors are intended to facilitate the description of the exemplary embodiments of the present invention, and are not intended to limit the structure of the exemplary embodiments of the present invention to any particular position or orientation. Terms of degree, such as “substantially” or “approximately” are understood by those of ordinary skill to refer to reasonable ranges around and including the given value, for example, general tolerances associated with manufacturing, assembly, and use of the described embodiments.
As shown in
The adhesive patch 16 and release liner 18 are formed with two sets of identical, aligned holes 32, 34 and 36, 38 as shown more clearly in
As shown in
More specifically, the rigid inner hub 40 is injection-molded in a first shot, and the flexible outer disk 42 is molded in a second shot during which the molten plastic material of the outer disk 42 flows around the rim 44 and through the holes 46. The shape of the rim 44 provides a double overlapping joint with the material of the flexible outer disk 42, and the holes 46 provide additional bonding surface area and additional mechanical interlocking.
The flexible outer disk 42 provides improved comfort and mobility of the infusion set base assembly 14 because it moves with the user during physical activity while minimizing contact of the rigid inner hub 40 with the user.
In embodiments of the invention, the patch assembly 19 can be die-cut from commercially available 3M™ Medical Nonwoven Tape (Product No. 1776). In this product, the patch material 16 is a ˜11.5 mil (0.3 mm) thick white spunlace nonwoven tape made of randomly oriented polyester fibers, the skin-contact adhesive 17 is an acrylate adhesive developed for medical/surgical use, and the release liner 18 is 83 lb. poly-coated Kraft paper of 6 mil (0.15 mm) thickness with a silicone release layer on both sides. Another suitable material is 3M™ Single Coated, Extended Wear Nonwoven Medical Tape (Product No. 4076). Still other materials that can be used are various single-coated medical tapes that are available from the Medical Materials and Technologies division of 3M Company. Other types of fibrous, textured, perforated or porous materials that are able to withstand the heat and pressure of the injection molding process can also be used for the adhesive patch 16 in the practice of the present invention.
In embodiments of the invention, the rigid inner hub 40 and flexible outer disk 42 may be made of any plastic materials that are suitable for injection molding. The rigid inner hub 40 is preferably made from a polyester blended material or polycarbonate, although this is not required. The flexible outer disk 42 is preferably made from a thermoplastic elastic material, some examples of which are listed in the table below. Materials that allow for molding of the flexible outer disk 42 at lower temperatures are preferred to avoid adverse effects on the skin contact adhesive 17 provided between the patch 16 and the release liner 18.
As previously noted, TPU and some other flexible materials sometimes have difficulty adhering to adhesive patches or pads such as adhesive patch 16 using only an adhesive. To solve this problem, in embodiments of the present invention, the flexible outer disk 42 is formed with one or more through-holes 60, as best shown in
According to one embodiment, the patch assembly 19 is simply placed in contact with the flexible outer disk 42 and the rigid inner hub 40 by the manufacturer. Preferably, however, the patch assembly 19 is adhered to the flexible outer disk 42 and the rigid inner hub 40 by the manufacturer using a patch adhesive, such as 3M 1522 Double-Coated Adhesive. At this stage, the one or more through-holes 60 are in communication with the top or non-patient side of the adhesive patch 16. Although the through-holes 60 are preferably substantially vertical, and cylindrical, the through-holes 60 can have any shape and angle with respect to the top and bottom surfaces of the outer flexible disk 42 so long as the manufacturer can communicate with the non-patient side of the adhesive patch 16 therethrough.
Adhesive or glue, such as Dymax 1405M or Loctite 3977 visible light cure adhesive, is dispensed by the manufacturer into the through-holes 60 onto the adhesive patch 16 and the walls of the outer flexible disk 42 surrounding the through-holes 60. As shown in
Although only a few embodiments of the present invention have been shown and described, the present invention is not limited to the described embodiments. Instead, it will be appreciated by those skilled in the art that changes may be made to these embodiments without departing from the principles and spirit of the invention. Any of the embodiments and/or elements disclosed herein may be combined with one another to form various additional embodiments not specifically disclosed, as long as they do not contradict each other. In other words, various aspects of the multiple embodiments may be employed independently or in combinations thereof. It is particularly noted that those skilled in the art can readily combine the various technical aspects of the various elements of the various exemplary embodiments that have been described above in numerous other ways, all of which are considered to be within the scope of the invention, which is defined by the appended claims and their equivalents.
This application claims the benefit of U.S. Provisional Application No. 62/864,795, filed Jun. 21, 2019 in the U.S. Patent and Trademark Office, the disclosure of which is incorporated herein by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 62864795 | Jun 2019 | US |
