SKIN PATCH TEST DEVICE
United States Patent 3703890
A plurality of individual applicators for performing skin patch tests are arrayed in spaced relation on an adhesively coated sheet of material for attachment to a patient's skin. A plurality of rupturable capsules or ampules are mounted with the adhesively coated sheet, each containing a different prepared test material or contactant, e.g. solid, particulate, etc., for contact with the subjects skin to enable a determination of whether the preselected contactant substances produce any local reactions with the patient's skin. The capsules or ampules are effectively isolated from each other to prevent interaction between the various test materials contained in each of the capsules or ampules.
US Patent References:
BANDAGE CONTAINING A MEDICINAL MATERIAL AND METHOD OF USING
Stuart - May 1971 - 3580254
Medical appliance
Laub - March 1941 - 2235436
Sensitivity test patches
Osbourn et al. - October 1965 - 3212495
TEST PATCH FOR DIAGNOSING ALLERGIES
Fregert - June 1970 - 3515126
Article of manufacture for intracutaneous injections
Wagner et al. - July 1959 - 2893392
BANDAGE CONTAINING A MEDICINAL MATERIAL AND METHOD OF USING
Stuart - May 1971 - 3580254
Medical appliance
Laub - March 1941 - 2235436
Sensitivity test patches
Osbourn et al. - October 1965 - 3212495
TEST PATCH FOR DIAGNOSING ALLERGIES
Fregert - June 1970 - 3515126
Article of manufacture for intracutaneous injections
Wagner et al. - July 1959 - 2893392
Application Number:
05/062480
Publication Date:
11/28/1972
Filing Date:
08/10/1970
View Patent Images:
Export Citation:
Primary Class:
Other Classes:
604/307, 604/289
International Classes:
A61B10/00; A61B10/00
Field of Search:
128/2W,2R,253,268 23/253TP 429/7
US Patent References:
Primary Examiner:
Howell, Kyle L.
Claims:
What is claimed is
1. A device for performing simultaneously a plurality of skin patch tests to determine the sensitivity of a subject to substances which the skin may be sensitive, comprising a structure having an exposed adhesive surface adapted for being attached to the skin and having disposed on the said adhesive surface a plurality of reservoir means each containing a different one of said substances, each said reservoir means comprising an outer dome-shaped member and a rupturable capsule means disposed within said dome-shaped member, said capsule means containing said test substances, restraining means including an isolation groove and an annular ring surrounding each of said reservoir means for isolating each of said reservoir means from each other to prevent interaction between the different ones of said substances contained within each of said reservoir means
2. A device according to claim 1 wherein said rupturable capsule means contain a liguid substance and said restraining means includes means for effectively preventing leakage of said liquid substances beyond a predetermined local area.
3. A device according to claim 2 wherein said annular ring comprises similar material as said dome-shaped member.
4. A device according to claim 3 wherein ventilation apertures are provided within said isolation groove whereby air can be admitted to the area being tested to diminish masceration of the subject's skin.
5. A device according to claim 1 wherein said capsule means have a means disposed therein for puncturing said capsule when the device is ready for use.
6. A device according to claim 1 wherein said reservoir means includes seal means disposed about said dome shaped member so as to provide a substantially liquid tight compartment for said substance, and further including removable cover means disposed over said dome shaped member to provide a liquid tight device, whereby said device is ready for use by removal of said cover.
7. A device according to claim 1 wherein said reservoir means comprises a multi-lobate type configuration.
8. A device according to claim 7 wherein ventilation apertures are operably associated with each of said reservoir means.
9. A device according to claim 1 wherein said device includes a removable foldable closure disposed in sealed relation with said exposed adhesive surface thereby to form a completely enclosed package containing a battery of skin sensitivity patch tests.
10. A device for performing simultaneously a plurality of skin patch tests to determine the sensitivity of a subject to substances to which the skin may be sensitive, comprising a structure having an adhesive surface adapted for attachment to the skin and having disposed thereon an array of independent reservoir means containing different ones of said test substances, wherein said test substances are contained as an impregnated inert substance on a fabric patch, outer and inner sheet member, each of said patches being sealed in a substantially air and liquid tight compartment formed by individual patch-encompassing seals between said outer and inner sheet members, the inner one of said members being removable prior to the application of the array of said reservoir means to the subject's skin, and means for isolating each of said reservoir means from each other to prevent interaction between the different one of said substances contained within each of said reservoir means said means for isolating including an isolation groove and an annular ring.
11. A device according to claim 10 wherein said reservoir means comprises an outer member and rupturable capsule means disposed within said outer member for containing the test substance.
12. A device according to claim 10 wherein said reservoir means comprises an outer sheet member; said reservoir means having capsule means disposed therein; and said capsule means having means disposed therein for puncturing said capsule when the device is ready for use.
1. A device for performing simultaneously a plurality of skin patch tests to determine the sensitivity of a subject to substances which the skin may be sensitive, comprising a structure having an exposed adhesive surface adapted for being attached to the skin and having disposed on the said adhesive surface a plurality of reservoir means each containing a different one of said substances, each said reservoir means comprising an outer dome-shaped member and a rupturable capsule means disposed within said dome-shaped member, said capsule means containing said test substances, restraining means including an isolation groove and an annular ring surrounding each of said reservoir means for isolating each of said reservoir means from each other to prevent interaction between the different ones of said substances contained within each of said reservoir means
2. A device according to claim 1 wherein said rupturable capsule means contain a liguid substance and said restraining means includes means for effectively preventing leakage of said liquid substances beyond a predetermined local area.
3. A device according to claim 2 wherein said annular ring comprises similar material as said dome-shaped member.
4. A device according to claim 3 wherein ventilation apertures are provided within said isolation groove whereby air can be admitted to the area being tested to diminish masceration of the subject's skin.
5. A device according to claim 1 wherein said capsule means have a means disposed therein for puncturing said capsule when the device is ready for use.
6. A device according to claim 1 wherein said reservoir means includes seal means disposed about said dome shaped member so as to provide a substantially liquid tight compartment for said substance, and further including removable cover means disposed over said dome shaped member to provide a liquid tight device, whereby said device is ready for use by removal of said cover.
7. A device according to claim 1 wherein said reservoir means comprises a multi-lobate type configuration.
8. A device according to claim 7 wherein ventilation apertures are operably associated with each of said reservoir means.
9. A device according to claim 1 wherein said device includes a removable foldable closure disposed in sealed relation with said exposed adhesive surface thereby to form a completely enclosed package containing a battery of skin sensitivity patch tests.
10. A device for performing simultaneously a plurality of skin patch tests to determine the sensitivity of a subject to substances to which the skin may be sensitive, comprising a structure having an adhesive surface adapted for attachment to the skin and having disposed thereon an array of independent reservoir means containing different ones of said test substances, wherein said test substances are contained as an impregnated inert substance on a fabric patch, outer and inner sheet member, each of said patches being sealed in a substantially air and liquid tight compartment formed by individual patch-encompassing seals between said outer and inner sheet members, the inner one of said members being removable prior to the application of the array of said reservoir means to the subject's skin, and means for isolating each of said reservoir means from each other to prevent interaction between the different one of said substances contained within each of said reservoir means said means for isolating including an isolation groove and an annular ring.
11. A device according to claim 10 wherein said reservoir means comprises an outer member and rupturable capsule means disposed within said outer member for containing the test substance.
12. A device according to claim 10 wherein said reservoir means comprises an outer sheet member; said reservoir means having capsule means disposed therein; and said capsule means having means disposed therein for puncturing said capsule when the device is ready for use.
Description:
BACKGROUND OF THE INVENTION
The present invention relates to devices for performing tests on the skin to determine the sensitivity thereof to various substances and in particular to determine the presence or absence of local reaction to various substances.
More particularly, the invention relates to an improved and novel time-saving method and device for applying skin sensitivity patch tests, such tests being utilized by persons such as dermatologists and allergists to determine whether a selected contactant substance produces a local reaction with a subject's skin.
A common expedient for determining whether a subject is sensitive to a particular substance or substances involves the use of patch tests. Typically, a physician will prepare a skin area and then is obliged to separately apply the test solutions to fabric patches whereupon the patches are applied to the skin surface with the aid of adhesive strips. The manual application of these test materials is a slow and tedious operation because of the relatively great amount of care required in order to avoid any cross-contamination between the various applied substances. Such time consuming operations place a practical limit on the number of tests performed for each patient and thus, on the number of patients to whom these tests can be applied.
According to the present invention there exists a capability for applying a single operation a complete prefabricated battery of related or diversified screening tests which essentially makes it practical to obtain required diagnostic information quickly and easily. Briefly, the present invention overcomes the deficiencies and faults of the prior art by providing a novel and improved device comprising a plurality of individual applicators for use in performing skin patch tests arrayed in predetermined fashion on an adhesively coated sheet, which sheet is adapted for attachment to the patients's skin. A backing sheet, which attaches each of the individual applicators to the adhesive sheet, comprises preferably a non-thermoplastic material such as cotton or glass fiber fabric, and mounted on the backing sheet are a plurality of arrayed rupturable capsules or ampules. The capsules may be mounted either directly on the backing sheet or preferably a thermoplastic sheet may be employed for the mounting. A thermoplastic cover sheet is secured over the ampules, with the sheet being constructed and arranged to provide a plurality of isolation grooves or channels which surround the central portion of each of the capsules. By isolating the capsules cross contamination, between the various test materials or contactant substances contained within each of the capsules, is prevented effectively. Further, holes or apertures can be provided in each of the isolation grooves or channels for purpose of ventilation.
A preferred embodiment envisions a substantially central dome overlying each of the rupturable capsules. However, the capsules of the present invention may take other various forms, such as a multi-lobate arrangement wherein the patches are formed in a rosette configuration which permits the ventilation apertures to be located closer to the center of each test site and thus assures a maximum test area with close spacing of air vents. This is designated to admit air as a means of diminishing skin masceration which results from long soaking. A further modification contemplates elimination of the rupturable capsule or ampule in its entirety and comprises impregnating the contactant test material onto the patch proper. In this case the contactant is sealed between sheets of thermoplastic film in a manner later described. Another modification envisions that the contactant material itself might be utilized as a solid or semi-solid with the absorbant patch proper.
Accordingly, it is a primary object of the present invention to provide a novel and improved device for applying skin sensitivity patch tests in a single operation.
Another object of the present invention is to provide a novel and improved method and device for applying a pre fabricated battery of related skin sensitivity patch tests in a single operation.
A further object of the present invention is to provide a novel and improved device for performing skin sensitivity patch tests in a single operation wherein the test material is contained in a plurality of rupturable capsules arranged on an adhesively coated sheet for attachment to a subject's skin.
Still yet a further object of the present invention is to provide a novel and improved device for applying a battery of skin sensitivity related or screening patch tests in a single operation, wherein the test solutions are contained in isolated compartments, thereby preventing any cross-contamination between the various tests.
Having in mind the above and other objects that will be evident from an understanding of this disclosure, the invention comprises the combinations and arrangements and method of operation as illustrated and disclosed in the presently preferred embodiments of the invention which is hereinafter set forth in such detail as to enable those skilled in the art readily to understand the function, operation, construction and advantages of it when read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a top plan view of a device for applying a battery of skin sensitivity patch tests constructed in accordance with the present invention;
FIG. 2 illustrates a cross-sectional view taken substantially on the line 2--2 of FIG. 1 showing an enlargement of one of the individual applicators;
FIG. 3 illustrates a disassembled view of the various components of each individual applicator prior to assembly into the final individual patch or applicator;
FIG. 4 illustrates a third type of applicator;
FIG. 5 illustrates a second embodiment of the individual applicator of FIG. 1; and
FIG. 6 illustrates still yet another applicator embodiment comprising a self-rupturable capsule.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Having reference to the drawings wherein like reference numerals designate similar parts, the present invention is illustrated in FIG. 1 as comprising a skin sensitivity patch test device, generally designated 9, including a sheet 10 of adhesively coated material having the adhesive side exposed for attachment to a patient's skin. As illustrated, there are provided a plurality of individual applicators or patches 11, each of which contains a different test material or substance corresponding to the particular test to be performed. Since these patches are identical in construction only one need be described for purposes of understanding the present invention.
As illustrated in FIGS. 1 and 2 the device includes an impervious seal sheet 12 and 12 1 which folds so as to protect the mounted battery of applicators or patches during storage and handling. This folded sheet could be sealed along its free edges to form an enclosing envelope.
Each of the patches comprises a skin contact material and capsule cover, which may comprise a suitable material, for example, a knit thermoplastic fabric such as gauze for absorbing the contactant and transferring it to the subject's skin and also for effectively forming a cushion when the patch tests are applied to the skin. The central portion of the sheet 14 is formed in the shape of a central dome as best shown in FIG. 2. Within the central dome 14 there is provided a rupturable capsule or ampule 15 which contains the contactant preparation 25 for performing the particular test. In forming the patch in addition to the sheet 14 being formed into the aforementioned central dome portion, there also is formed and outer annular ring 14' which effectively is isolated from the central portion 14 by a buffer zone comprising an isolation groove 16 of annular shape. About the periphery of the central dome portion 14 there is provided an annular seal or dike for preventing leakage of the contactant beyond that boundary and which effectively defines the patch proper. The isolation groove or channel 16 is formed in a manner to be described in greater detail hereinafter and serves to break the fluid film of the contactant at the outer periphery 17 of the central dome portion 14 and thus, prevent any spread of the contactant beyond the desired local test area. As mentioned before, there is provided an annular outer ring or buffer zone 14', which provides additional protection in the event that inadvertant or accidental pressure is applied such as, for example, when the subject is sleeping and turns so as to place his weight directly on the test area, which may result in squeezing out of an excess amount of contactant from the patch proper or in other words, the area desired to be tested. Thus, by virtue of this buffer ring 14' the contactant is retained within the desired local area and is prevented from encroaching upon adjacent test areas. Further, the buffer zone 14' extends a neutral zone around each patch to a point where the adhesive 10 is in contact with the patient's skin. This is advantageous since many adhesives are irritants if not actual sensitizers and any skin reaction produced thereby and which might be contiguous to the edge of the test area, readily could interfere with the interpretation of the test.
Disposed within the patch or central dome portion is the rupturable capsule or ampule 15, which is made from a suitable material such as polypropylene or fluorohalocarbon film or laminate and which in this embodiment contains the contactant for performing the desired tests. As illustrated in FIGS. 1 and 2 there is provided a plurality of circumferentially arranged spaced ventilation holes or apertures 18 disposed within the isolation grooves 16. These ventilation holes extend through the ventilated adhesive sheet 10 and terminate at an impervious adhesive sheet 13. After the battery of tests is applied to the patient's skin; by leaving the sheet 13 in place each of the patches is completely occlusive, that is, sealed to the skin, permitting no air to circulate between patch and skin. By removing this outer backing, sheet 13, the patches become ventilated, allowing relatively free air passage between patch and skin.
As illustrated in FIG. 2, it should be noted that in the formation of the isolation groove 16 the central and outer portions 14, 14' of each applicator or patch 11 are effectively unitarily or integrally formed. The disassembled view shown in FIG. 3 illustrates the elements of the patch prior to its assembly into final form. Thus, the central dome portion 14 and the outer ring 14' are formed from a single sheet of suitable fabric material. The capsule or ampule 15, as mentioned herein before, is filled with the contactant material 25 and may comprise any suitable glass or plastic, such as polypropylene or fluorohalocarbon film or laminate. The sheet 19 made of a compatible material is optional and may be employed depending upon whether additional fusible material is desirable to thicken and strengthen the dike and seal area. The backing material 20 which forms the back of the patch 11, comprises a non-thermoplastic fabric such as woven vegetable fiber or glass fiber. By application of a suitable die of the heated variety in the vicinity of the isolation groove or channel 16 the various thermoplastic sheets will be fused against the backing sheet 20 and effectively will form the dike or isolation wall 17 at the periphery of the central dome portion 14 thereby making the back and sides of the patch proper liquid tight as well as securing and bonding all of the patch components together. By arranging a suitable cutting die in proper fashion the patch can be completed by cutting it free from the surrounding material as illustrated. It should be noted at this point that the particular type of machinery employed in the formation of the patch does not form part of the present invention; suffice it to say that any suitable, conventional type sealing system for thermoplastics, employing contact heating of continuous, or thermal impulse types; or high frequency hypersonic, or radio frequency methods will be satisfactory. To facilitate an understanding of the present invention, the method of forming the patches will be briefly described herein.
First, the capsules may be formed by deeply embossing a sheet of thermoplastic 15' to form the particular chambers. A flat plate template, with machined recesses of the desired shape located at pre-determined intervals, constitutes the lower and fixed half of the embossing die. The sheet of thermoplastic then is stretched over the template and male projections on the upper half of the die will enter the matching recesses of the lower half, thus stretching and deforming the sheet at these particular points. The embossed sheet remains in the lower template after the upper half has been lifted. The desired contactant substances then are measured into the cavities which are allowed to be filled about three-quarters full. Then a sheet of compatible thermoplastic 15" is laid over the whole area and is heat sealed to the embossed sheet in small areas surrounding the now complete filled capsules. The sheet of filled capsules so formed then is lifted out of the lower template and turned over. Under it is placed a sheet 19 of compatible thermoplastic material and still further directly beneath this sheet is a layer of non-thermoplastic material, 20 preferably of a woven, largely vegetable fiber or glass fabric. A layer of one or more thicknesses of the thermoplastic woven or knit fabric then is laid over the assembled parts previously described above. A heated die then is applied to the stacked materials whereupon the thermoplastic materials are compressed and fused against the backing fabric, 20 which, being infusible, functions to bind the entire patch together. As the die is withdrawn the fused material along the periphery of the central dome portion 14 solidifies so as to form a liquid tight barrier or dike 17 which will prevent the loss of any contactant solution from the test site after the capsule has been ruptured and the test patch applied to the patient. At this point in the manufacture of the device the individual patches may be cut out of the sheet and a plurality of perforations may be made in the sealed area. The entire sheet then is transferred to the adhesive face of the tape 10 and thus, a complete battery of test patches is mounted at desired spacing intervals. The cut-out waste material between individual patches is pealed away leaving an adhesive surface surrounding each patch for holding the unit firmly in contact with the patient's skin during performance of the test.
Although it has been disclosed that the capsule or ampule 15 may comprise a plastic material, it is also within the scope of this invention to make the capsule of glass or other suitable material. In the latter case the heretofore mentioned optional thermoplastic sheet 19 is necessary for having the glass ampule suitably attached thereto to facilitate assembly.
As illustrated in FIG. 5 there is shown a variation of the circular patch heretofore described and illustrated in FIGS. 1 to 3 inclusive. This particular embodiment places greater emphasis on the ventilation and accordingly, comprises a multilobate shaped central dome 21 having the vent holes 18 located in the annular isolation groove or channel 16 at the cusp point where each of the lobes intercept adjacent lobes. Thus, it is apparent that the vent holes will be nearer the center of the test area as compared with the previously described circular patch, assuming that the areas were made to be equal, and secondly, improvements result because of the contour of the surface of the lobe-shaped dome which tend to more readily admit air to the test site. The ventilation holes or apertures 18 extend completely through the backing material 20, as well as through the adhesive sheet 10, for communication with the surrounding atmosphere. It should be noted that the impervious adhesive sheet 13 is removed when the fully ventilated patch is desired. Thus, this is advantageous since the patches are likely to be worn by the patient for forty-eight hours or occasionally longer, and it is likely that variable pressures due to changes in the subject's position and movement of clothing will occur, thereby causing air to flow in and out, which is desired for a fully ventilated patch.
A variation of the patches described heretofore is illustrated in FIG. 4, where the patch dome portion 14 is per se encapsulated with the contactant material impregnated onto the pad. In this embodiment it is essential that there be provided a suitable preformed front seal sheet 22 over the entire patch and which would be peeled off so as to expose the patch when ready for use, that is, just prior to application. Thus, in peeling off this seal 22 it is important that the various parts be separated cleanly without any mutilation of the battery of patches. This has the advantages of ease of application since it is not required that individual capsules be ruptured in preparation for application.
A still yet further embodiment illustrated in FIG. 6 comprises the use of a cutting member, or members 23, which may comprise plastic or other suitable material, having raised relatively sharp edges or burrs 24 about its periphery. By employing this type of patch construction the capsule 15 readily can be ruptured merely be exerting pressure on the central dome portion 14 whereupon the plastic material forming the capsule will be punctured by the sharp edges or burrs 24 of the insert 23.
Another possibility that falls within the scope of the present invention is the use of micro-encapsulation wherein micro-capsules would be properly secured (e.g. by adhesive) to the front surface of the patch and would be ruptured by exerting a force thereon before or as the patch is applied to the patient's skin.
ORIENTATION MARKS
Transferrable identification or orientation markings may be included in or on the adhesive surface surrounding test sites. Skin markings thus produced will be visible after removal of the test battery, exactly locating and/or identifying each test substance. Perforations, sufficiently closely spaced, will be made along lines, 28, FIG. 1 to permit removal of any patch, prior to, or during the test period without disturbing adjacent patches.
It will be appreciated from the foregoing description that there has been provided a novel and improved device and method for applying skin sensitivity patch tests in a single operation, which enjoys significant advantages over previously available devices.
It should be under stood that the construction and arrangement herein illustrated and described is intended to be representative of preferred embodiments only and that certain changes may be made therein without departing from the clear teachings of the present disclosure. Accordingly, reference should be made to the following appended claims in determining the full scope of the invention.
The present invention relates to devices for performing tests on the skin to determine the sensitivity thereof to various substances and in particular to determine the presence or absence of local reaction to various substances.
More particularly, the invention relates to an improved and novel time-saving method and device for applying skin sensitivity patch tests, such tests being utilized by persons such as dermatologists and allergists to determine whether a selected contactant substance produces a local reaction with a subject's skin.
A common expedient for determining whether a subject is sensitive to a particular substance or substances involves the use of patch tests. Typically, a physician will prepare a skin area and then is obliged to separately apply the test solutions to fabric patches whereupon the patches are applied to the skin surface with the aid of adhesive strips. The manual application of these test materials is a slow and tedious operation because of the relatively great amount of care required in order to avoid any cross-contamination between the various applied substances. Such time consuming operations place a practical limit on the number of tests performed for each patient and thus, on the number of patients to whom these tests can be applied.
According to the present invention there exists a capability for applying a single operation a complete prefabricated battery of related or diversified screening tests which essentially makes it practical to obtain required diagnostic information quickly and easily. Briefly, the present invention overcomes the deficiencies and faults of the prior art by providing a novel and improved device comprising a plurality of individual applicators for use in performing skin patch tests arrayed in predetermined fashion on an adhesively coated sheet, which sheet is adapted for attachment to the patients's skin. A backing sheet, which attaches each of the individual applicators to the adhesive sheet, comprises preferably a non-thermoplastic material such as cotton or glass fiber fabric, and mounted on the backing sheet are a plurality of arrayed rupturable capsules or ampules. The capsules may be mounted either directly on the backing sheet or preferably a thermoplastic sheet may be employed for the mounting. A thermoplastic cover sheet is secured over the ampules, with the sheet being constructed and arranged to provide a plurality of isolation grooves or channels which surround the central portion of each of the capsules. By isolating the capsules cross contamination, between the various test materials or contactant substances contained within each of the capsules, is prevented effectively. Further, holes or apertures can be provided in each of the isolation grooves or channels for purpose of ventilation.
A preferred embodiment envisions a substantially central dome overlying each of the rupturable capsules. However, the capsules of the present invention may take other various forms, such as a multi-lobate arrangement wherein the patches are formed in a rosette configuration which permits the ventilation apertures to be located closer to the center of each test site and thus assures a maximum test area with close spacing of air vents. This is designated to admit air as a means of diminishing skin masceration which results from long soaking. A further modification contemplates elimination of the rupturable capsule or ampule in its entirety and comprises impregnating the contactant test material onto the patch proper. In this case the contactant is sealed between sheets of thermoplastic film in a manner later described. Another modification envisions that the contactant material itself might be utilized as a solid or semi-solid with the absorbant patch proper.
Accordingly, it is a primary object of the present invention to provide a novel and improved device for applying skin sensitivity patch tests in a single operation.
Another object of the present invention is to provide a novel and improved method and device for applying a pre fabricated battery of related skin sensitivity patch tests in a single operation.
A further object of the present invention is to provide a novel and improved device for performing skin sensitivity patch tests in a single operation wherein the test material is contained in a plurality of rupturable capsules arranged on an adhesively coated sheet for attachment to a subject's skin.
Still yet a further object of the present invention is to provide a novel and improved device for applying a battery of skin sensitivity related or screening patch tests in a single operation, wherein the test solutions are contained in isolated compartments, thereby preventing any cross-contamination between the various tests.
Having in mind the above and other objects that will be evident from an understanding of this disclosure, the invention comprises the combinations and arrangements and method of operation as illustrated and disclosed in the presently preferred embodiments of the invention which is hereinafter set forth in such detail as to enable those skilled in the art readily to understand the function, operation, construction and advantages of it when read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a top plan view of a device for applying a battery of skin sensitivity patch tests constructed in accordance with the present invention;
FIG. 2 illustrates a cross-sectional view taken substantially on the line 2--2 of FIG. 1 showing an enlargement of one of the individual applicators;
FIG. 3 illustrates a disassembled view of the various components of each individual applicator prior to assembly into the final individual patch or applicator;
FIG. 4 illustrates a third type of applicator;
FIG. 5 illustrates a second embodiment of the individual applicator of FIG. 1; and
FIG. 6 illustrates still yet another applicator embodiment comprising a self-rupturable capsule.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Having reference to the drawings wherein like reference numerals designate similar parts, the present invention is illustrated in FIG. 1 as comprising a skin sensitivity patch test device, generally designated 9, including a sheet 10 of adhesively coated material having the adhesive side exposed for attachment to a patient's skin. As illustrated, there are provided a plurality of individual applicators or patches 11, each of which contains a different test material or substance corresponding to the particular test to be performed. Since these patches are identical in construction only one need be described for purposes of understanding the present invention.
As illustrated in FIGS. 1 and 2 the device includes an impervious seal sheet 12 and 12 1 which folds so as to protect the mounted battery of applicators or patches during storage and handling. This folded sheet could be sealed along its free edges to form an enclosing envelope.
Each of the patches comprises a skin contact material and capsule cover, which may comprise a suitable material, for example, a knit thermoplastic fabric such as gauze for absorbing the contactant and transferring it to the subject's skin and also for effectively forming a cushion when the patch tests are applied to the skin. The central portion of the sheet 14 is formed in the shape of a central dome as best shown in FIG. 2. Within the central dome 14 there is provided a rupturable capsule or ampule 15 which contains the contactant preparation 25 for performing the particular test. In forming the patch in addition to the sheet 14 being formed into the aforementioned central dome portion, there also is formed and outer annular ring 14' which effectively is isolated from the central portion 14 by a buffer zone comprising an isolation groove 16 of annular shape. About the periphery of the central dome portion 14 there is provided an annular seal or dike for preventing leakage of the contactant beyond that boundary and which effectively defines the patch proper. The isolation groove or channel 16 is formed in a manner to be described in greater detail hereinafter and serves to break the fluid film of the contactant at the outer periphery 17 of the central dome portion 14 and thus, prevent any spread of the contactant beyond the desired local test area. As mentioned before, there is provided an annular outer ring or buffer zone 14', which provides additional protection in the event that inadvertant or accidental pressure is applied such as, for example, when the subject is sleeping and turns so as to place his weight directly on the test area, which may result in squeezing out of an excess amount of contactant from the patch proper or in other words, the area desired to be tested. Thus, by virtue of this buffer ring 14' the contactant is retained within the desired local area and is prevented from encroaching upon adjacent test areas. Further, the buffer zone 14' extends a neutral zone around each patch to a point where the adhesive 10 is in contact with the patient's skin. This is advantageous since many adhesives are irritants if not actual sensitizers and any skin reaction produced thereby and which might be contiguous to the edge of the test area, readily could interfere with the interpretation of the test.
Disposed within the patch or central dome portion is the rupturable capsule or ampule 15, which is made from a suitable material such as polypropylene or fluorohalocarbon film or laminate and which in this embodiment contains the contactant for performing the desired tests. As illustrated in FIGS. 1 and 2 there is provided a plurality of circumferentially arranged spaced ventilation holes or apertures 18 disposed within the isolation grooves 16. These ventilation holes extend through the ventilated adhesive sheet 10 and terminate at an impervious adhesive sheet 13. After the battery of tests is applied to the patient's skin; by leaving the sheet 13 in place each of the patches is completely occlusive, that is, sealed to the skin, permitting no air to circulate between patch and skin. By removing this outer backing, sheet 13, the patches become ventilated, allowing relatively free air passage between patch and skin.
As illustrated in FIG. 2, it should be noted that in the formation of the isolation groove 16 the central and outer portions 14, 14' of each applicator or patch 11 are effectively unitarily or integrally formed. The disassembled view shown in FIG. 3 illustrates the elements of the patch prior to its assembly into final form. Thus, the central dome portion 14 and the outer ring 14' are formed from a single sheet of suitable fabric material. The capsule or ampule 15, as mentioned herein before, is filled with the contactant material 25 and may comprise any suitable glass or plastic, such as polypropylene or fluorohalocarbon film or laminate. The sheet 19 made of a compatible material is optional and may be employed depending upon whether additional fusible material is desirable to thicken and strengthen the dike and seal area. The backing material 20 which forms the back of the patch 11, comprises a non-thermoplastic fabric such as woven vegetable fiber or glass fiber. By application of a suitable die of the heated variety in the vicinity of the isolation groove or channel 16 the various thermoplastic sheets will be fused against the backing sheet 20 and effectively will form the dike or isolation wall 17 at the periphery of the central dome portion 14 thereby making the back and sides of the patch proper liquid tight as well as securing and bonding all of the patch components together. By arranging a suitable cutting die in proper fashion the patch can be completed by cutting it free from the surrounding material as illustrated. It should be noted at this point that the particular type of machinery employed in the formation of the patch does not form part of the present invention; suffice it to say that any suitable, conventional type sealing system for thermoplastics, employing contact heating of continuous, or thermal impulse types; or high frequency hypersonic, or radio frequency methods will be satisfactory. To facilitate an understanding of the present invention, the method of forming the patches will be briefly described herein.
First, the capsules may be formed by deeply embossing a sheet of thermoplastic 15' to form the particular chambers. A flat plate template, with machined recesses of the desired shape located at pre-determined intervals, constitutes the lower and fixed half of the embossing die. The sheet of thermoplastic then is stretched over the template and male projections on the upper half of the die will enter the matching recesses of the lower half, thus stretching and deforming the sheet at these particular points. The embossed sheet remains in the lower template after the upper half has been lifted. The desired contactant substances then are measured into the cavities which are allowed to be filled about three-quarters full. Then a sheet of compatible thermoplastic 15" is laid over the whole area and is heat sealed to the embossed sheet in small areas surrounding the now complete filled capsules. The sheet of filled capsules so formed then is lifted out of the lower template and turned over. Under it is placed a sheet 19 of compatible thermoplastic material and still further directly beneath this sheet is a layer of non-thermoplastic material, 20 preferably of a woven, largely vegetable fiber or glass fabric. A layer of one or more thicknesses of the thermoplastic woven or knit fabric then is laid over the assembled parts previously described above. A heated die then is applied to the stacked materials whereupon the thermoplastic materials are compressed and fused against the backing fabric, 20 which, being infusible, functions to bind the entire patch together. As the die is withdrawn the fused material along the periphery of the central dome portion 14 solidifies so as to form a liquid tight barrier or dike 17 which will prevent the loss of any contactant solution from the test site after the capsule has been ruptured and the test patch applied to the patient. At this point in the manufacture of the device the individual patches may be cut out of the sheet and a plurality of perforations may be made in the sealed area. The entire sheet then is transferred to the adhesive face of the tape 10 and thus, a complete battery of test patches is mounted at desired spacing intervals. The cut-out waste material between individual patches is pealed away leaving an adhesive surface surrounding each patch for holding the unit firmly in contact with the patient's skin during performance of the test.
Although it has been disclosed that the capsule or ampule 15 may comprise a plastic material, it is also within the scope of this invention to make the capsule of glass or other suitable material. In the latter case the heretofore mentioned optional thermoplastic sheet 19 is necessary for having the glass ampule suitably attached thereto to facilitate assembly.
As illustrated in FIG. 5 there is shown a variation of the circular patch heretofore described and illustrated in FIGS. 1 to 3 inclusive. This particular embodiment places greater emphasis on the ventilation and accordingly, comprises a multilobate shaped central dome 21 having the vent holes 18 located in the annular isolation groove or channel 16 at the cusp point where each of the lobes intercept adjacent lobes. Thus, it is apparent that the vent holes will be nearer the center of the test area as compared with the previously described circular patch, assuming that the areas were made to be equal, and secondly, improvements result because of the contour of the surface of the lobe-shaped dome which tend to more readily admit air to the test site. The ventilation holes or apertures 18 extend completely through the backing material 20, as well as through the adhesive sheet 10, for communication with the surrounding atmosphere. It should be noted that the impervious adhesive sheet 13 is removed when the fully ventilated patch is desired. Thus, this is advantageous since the patches are likely to be worn by the patient for forty-eight hours or occasionally longer, and it is likely that variable pressures due to changes in the subject's position and movement of clothing will occur, thereby causing air to flow in and out, which is desired for a fully ventilated patch.
A variation of the patches described heretofore is illustrated in FIG. 4, where the patch dome portion 14 is per se encapsulated with the contactant material impregnated onto the pad. In this embodiment it is essential that there be provided a suitable preformed front seal sheet 22 over the entire patch and which would be peeled off so as to expose the patch when ready for use, that is, just prior to application. Thus, in peeling off this seal 22 it is important that the various parts be separated cleanly without any mutilation of the battery of patches. This has the advantages of ease of application since it is not required that individual capsules be ruptured in preparation for application.
A still yet further embodiment illustrated in FIG. 6 comprises the use of a cutting member, or members 23, which may comprise plastic or other suitable material, having raised relatively sharp edges or burrs 24 about its periphery. By employing this type of patch construction the capsule 15 readily can be ruptured merely be exerting pressure on the central dome portion 14 whereupon the plastic material forming the capsule will be punctured by the sharp edges or burrs 24 of the insert 23.
Another possibility that falls within the scope of the present invention is the use of micro-encapsulation wherein micro-capsules would be properly secured (e.g. by adhesive) to the front surface of the patch and would be ruptured by exerting a force thereon before or as the patch is applied to the patient's skin.
ORIENTATION MARKS
Transferrable identification or orientation markings may be included in or on the adhesive surface surrounding test sites. Skin markings thus produced will be visible after removal of the test battery, exactly locating and/or identifying each test substance. Perforations, sufficiently closely spaced, will be made along lines, 28, FIG. 1 to permit removal of any patch, prior to, or during the test period without disturbing adjacent patches.
It will be appreciated from the foregoing description that there has been provided a novel and improved device and method for applying skin sensitivity patch tests in a single operation, which enjoys significant advantages over previously available devices.
It should be under stood that the construction and arrangement herein illustrated and described is intended to be representative of preferred embodiments only and that certain changes may be made therein without departing from the clear teachings of the present disclosure. Accordingly, reference should be made to the following appended claims in determining the full scope of the invention.