Note: Descriptions are shown in the official language in which they were submitted.
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THERAPEUTIC FILM FORMING COMPOSITION
AND TREATMENT SYSTEM THEREFOR
TECHNICAL FIELD
This invention relates to diseases found in and beneath fingernails, toe-nails
and on skin surfaces and, more particularly, to a fully integrated treatment
system
for delivering drug therapy to diseases affecting nails and skin surfaces.
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BACKGROUND ART
Diseases which affect the skin surfaces and/or the fingernails and/or toenails
of individuals are extremely common and often create substantial difficulties
for the
individuals who are effected. As detailed herein, a wide variety of the
diseases have
been found to afflict individuals in this manner, with no realistically
effective
remedy being available.
In order to recognize the difficulties encountered in this area, it is
important
to understand the unique structure of nails. As is well known, the nail is a
unique
keratinous appendage that is produced by the germinative epithelium of the
matrix.
The construction of a typical nail is similar to the construction of the skin
surface in
which the basal epidermal cells produce the stratum corneum. However, the nail
has a harder keratin than the skin because of the higher concentration of
sulfur
matrix protein.
The nail grows continuously without a resting phase by adding new cells
from the matrix. The epithelial components of the nail unit include the
proximal
nail fold that is similar to the skin or slightly acanthotic, with a granular
layer
having active mitotic activity. The horny end product is the cuticle. The
matrix is
acanthotic without a granular layer with very inactive mitotic activity. The
horny
end product is the nail plate. The nail bed is very flat without a granular
layer with
very inactive mitotic activity and only a few horny cells added to the
underside of
the nail plate as it moves distally. Finally, the hyponychium is acanthotic,
with a
granular layer having active mitotic activity, with only a few horny cells
added to
the underside of the nail plate distally, similar to the cuticle.
A wide variety of problems can be incurred either in the nail itself or below
the nail surface in treating nails and diseases of the nail. In order to fully
understand the magnitude of this problem, the following tables are provided as
representative sample listings of various diseases, disorders, and medical
problems
that can be experienced and are in need of effective treatment:
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TABLE A
Dermatolo~ical Diseases that Affect the Nail
Psoriasis/pustular psoriasis
Lichen Planus
Idiopathic Atrophy of the nail
Lichen Nitidus
Lichen Striatus
Inflammatory Linear Verrucous Epidermal News
Alopecia Areata
Twenty-Nail Dystrophy (Trachyonychia)
Eczema with nail involvement
Pornpholyx with nail involvement
Parakeratosis pustalosa
Pemphigus Vulgaris
Bullous Pemphigoid
Acquired Epidermolysis Bullosa
Erythema Multiforme with nail involvement
Darier's Disease
Pityriasis Rubra Pilaris
Palmoplantar Keratoderma
Bazex Syndryome
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TABLE B
Nail Involvement in Systemic Diseases
Onycholysis which is the third most common nail disorder seen in
dermatology, after onychomycosis and warts.
Chromonychia
Hemorrhagic condition
Onychomadesis (complete onyholysysis or spontaneous nail shedding)
Hapalonychia (soft nail)
Onychorrhexis (senile, old nail)
Trachyonychia
TABLE C
Tumors of the Nails
Epidermal Tumors
Benign
Subungual corn
Wart
Cysts (Epidermal Inclusion/Epidermoid cyst)
Onychomatricoma
Melanocytic Tumors
Glomus Tumor
Myxoid Cyst
Pyogenic Granuloma
Malignant
Bowen's disease/squamous cell carcinoma
Maligant Melonoma
Dermal Tumors
Benign
Fibroma
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Vascular Tumors
Glomus Tumor
Pyogenic Granuloma
Splinter Hemorrhages
Subungeal Tumors
Subungeal exostosis
Subungeal Hematomas
Pigmented Disorders
Hypo/Hypermelanosis/melanonychia
Infections
Fungal infections (dermatophytes, yeast, deep fungus)
Bacterial infections (gram positive, gram negative bacteria, etc.)
Viral Infections (herpes simplex, warts, etc.)
Other Infections (Atypical Mycobacteria, sporotrichosis,
leishmaniasis etc.)
Mixed Infection (paronichia)
TABLE D
Congenital Keratinizing Disorders
Darier-White Disease
Pachonichia Congenita
Congenital Onychodysplasia
Epidermolysis bullosa
Twenty-Nail Dystrophy
Pityriasis Rubra Pilaris
Lamellar Ichthyosis
Epidermolytic Hyperkeratosis
Porokeratosis
Palmoplantar keratoderma
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Periodic Shedding of the the nails
Ectodermal Dysplasia
Rothmund-Thompson Syndrome
Dyskeratosis Congenita
Acrodermatitis enteropatica
Goldtz' Syndrome
Kid Syndrome
TABLE E
Nail Chan~es/Disorders Associated with Aging
Changes
Discoloration
Contour/Shape
Surface abnormality
Thickness
Decreased Linear Growth
Disorders
Brittle Nails
Onychodystrophy - exogenous
Onychauxis
Onychoclavus (subungeal corn)
Onychocryptosis (Ingrown nail)
Onychogryphosis
Splinter Hemorrhages
Subungeal Hematoma
2 5 Nail Infection
One of the areas that has proven to be extremely difficult for individuals to
obtain an effective remedy is found in the treatment of psoriasis,
particularly
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psoriasis associated with fingernails or toenails. It is estimated that there
are more
than 6.4 million cases of psoriasis in the United States, affecting about 2 %
to 3 % of
the general American population. According to the National Psoriasis
Foundation,
about 200,000 new cases are diagnosed every year, with an annual total
outpatient
cost of between about $1.6 in $3.2 billion being incurred. Furthermore, it is
estimated that 56 million hours of work are lost each year by patients with
psoriasis.
Psoriasis of the nails is very common and has been found in up to 50% of all
patients. The fingernails seem to be affected more often than toenails, which
presents an additional problem since patients are more likely to complain
about nail
changes which are readily visible. As a result, the effects of psoriatic nail
disease
are both physical and psychological.
The clinical signs of psoriasis of the nails are dependent upon the anatomic
sites of the nail unit that is involved. The defects vary greatly and include
pitting of
one or more nails, discoloration, thickening, and onycholysis (separation from
the
nail bed). The effect of onycholysis can also involve the underlying subungual
build-up similar to onychomycoses. Other changes commonly found are nail plate
dystrophy, Mee's lines (transverse white lines in the nail plate), Muehrcke's
lines
(transverse white lines due to abnormal vascular pattern in the nail bed
visible
through the nail plate), splitting of the nail plate, Beau's lines (transverse
furrow in
the nail plate generally due to intermittent matrix psoriasis), splinter
hemorrhage,
and subungual hyperkerertosis.
The objective of treating psoriatic nail disease is to improve the physical
and
physchosocial debilitation associated with nail dystrophy. Unfortunately, no
treatment presently in use is capable of curing psoriatic nails. Although
numerous
attempts and treatment modalities presently exist in the prior art, there is
no specific
consistently effective treatment for nail psoriasis.
Many modalities have been used, including topical, intralesional, and
systemic modalities, radiation therapy, etc. However, most of these prior art
treatment modalities had substantial risks and complications, including
systemic
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_g_
toxicity, post-radiation complications, atrophy of the surrounding skin, pain,
etc. In
addition, nail lacquers have been proposed in various prior art formulations
for
application to the nail for treating psoriasis, as well as many other nail
disorders.
However, these prior art nail lacquers have also proven to be ineffective in
resolving the nail diseases for which they were intended. As a result, a long-
felt
need has continued to exist for a safe, effective treatment system for nails
and nail
diseases, with no satisfactory proposal being found until the present
invention that
will be easy to use, safe, and cost efficient.
Therefore, it is a principal object of the present invention to provide a
treatment system for humans which is capable of being conveniently and easily
employed on any desired surface of a human, including the nail surface and
skin
surface, providing a quick drying film, which incorporates desired therapeutic
agents for treating various medical problems.
Another object of the present invention is to provide a highly effective
treatment system having the characteristics featured detailed above which also
employs a heat gradient to further enhance the delivery of the therapeutic
agents.
Another object of the present invention is to provide a highly effective
treatment system having the characteristics featured detailed above which is
capable
of being easily and effectively employed for treating a wide variety of
medical
conditions.
Another object of the present invention is to provide a highly effective
treatment system having the characteristics featured detailed above which also
incorporates a holding and supporting member constructed or cooperation with
the
film forming composition and the heat producing member to assure ease of
application and use.
Other and more specific objects will in part be obvious and will in part
appear hereinafter.
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DETAILED DESCRIPTION
By employing in the present invention, all of the difficulties and drawbacks
found in prior art compositions, systems, methods and procedures are
eliminated,
and a local, easily employed, convenient, consumer-oriented treatment system
is
achieved for treating nails and/or skin surfaces having a wide variety of
medical
problems. In the present invention, a treatment system is attained which
comprises
a film forming composition incorporating one or more therapeutic substances
for
application to nails and/or skin surfaces which can be employed independently
or, if
desired, in combination with an easily employed holding or support member for
delivering heat directly to the application site.
The treatment system of the present invention possesses broad applicability
for a wide range of medical conditions. In particular, the numerous diseases,
disorders, and medical problems detailed above are all capable of being
treated
using the present invention. In particular, diseases, disorders, and medical
conditions including, but not limited to psoriasis, skin cancers, warts,
leishmaniasis,
mycobacteria, and granuloma annulare can be specifically treated or improved
due
to the efficacy of the present invention and, when employed, the efficacy of
heat
penetration in treating these disorders.
In this regard, it has been established that the application of heat slows,
inhibits, or reverses metabolic processes, immunological processes, or
biological
conditions or processes which depend upon heat or are affected by heat. As a
result,
numerous medical conditions are effectively treated by employing the
therapeutic or
drug bearing film forming compositions detailed herein in combination with a
heating source, in accordance with the embodiment of this invention which
comprises the integrated treatment system.
It has also been found that the use of heat produces a positive, synergistic
effect on the targeted, controlled delivery of predetermined amounts of drugs,
and/or penetration enhancing agents. In this regard, the topical use of the
drugs
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and/or penetration enhancing agents for the treatment of the nail diseases,
disorders,
and medical conditions and/or skin and subcutaneous surfaces, as fully
detailed
above, are improved or effectively treated by the use of the present
invention.
Furthermore, the delivery of drugs and/or penetration enhancing agents to the
nail,
or through the nail to the underlying tissue, for the purpose of achieving a
non-oral
and/or non-parenteral, systemic, transdermal delivery is effective on its own
and is
further enhanced by the presence of a controlled heat gradient.
Generally, the treatment system of the present invention is detailed below in
association with its application to nails and the underlying tissue associated
with
nails. However, the present invention has equal applicability to diseases,
disorders,
and medical problems found on skin surfaces which are unassociated with nails.
Consequently, it is to be understood that the present invention and the
disclosure
provided herein is equally applicable to use on any skin surface.
Consequently, the
detailed use and application to the nails is provided for exemplary purposes
only
and, as a result, the present invention is intended to encompass application
and use
on both nails and skin surfaces.
One principal component of the present invention is a film forming
composition which is specifically formulated for delivering one or more
therapeutic
substances to the site on which it is applied. While usable on any surface of
the
human body, the film forming position is particularly usable on nails for
treating
any desired nail disease.
In addition to comprising one or more therapeutic substances, the film
forming composition of this invention also preferably comprises a film former,
a
plasticizer, and urea, all of which are in a volatile carrier. By referring to
Table I,
the formulation ranges for each ingredient are readily apparent. In this
Table, both
the overall usable ranges and preferred ranges are provided.
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TABLE I
Ingredient Overall Range Preferred Range
( % w/v) ( % w/v)
Film Former 0.5 - 25 5 - 10
Plasticizer 0.5 - 25 1 - 5
Urea 0.5 - 20 1 - 6
Therapeutic SubstancesRequired EffectiveRequired Effective
Amt. Amt
Solvent/Volatile Carrier40 - 90 50 - 80
In forming the composition of the present invention, any desired film former
may be employed. However, in the preferred composition, the film former
comprises at least one selected from the group consisting of polyvinyl
acetate, mixed
polymers of vinyl acetate and acrylic acid, mixed polymers of (meth) acrylic
acid
and (meth) acrylate esters, polyvinyl acetate, polyvinyl butyryl, polyvinyl
alcohols,
cellulose derivatives such as cellulose acetate phthalate, cellulose acetate
butyrate,
cellulose acetate propionate, cellulose nitrate, cellulose sulfate,
ethylcellulose, and
cellulose acetate. In this regard, one preferred film former is ammonio
methacrylate
copolymer (II) sold under the brand name "Eudragit RL-100" by Rohm Pharma
GmbH, Weiterstadt, Germany.
In addition, any desired plasticizers may be employed. However, in the
preferred composition, the plasticizer composition comprises as least one
selected
from the group consisting of triacetin, polyhydric alcohols such as propylene
glycol
and butylene glycol, castor oil, camphor and phthalates. In this regard, one
preferred plasticizer comprises dibutyl phthalate, sold under the brand name
"Eastman DBT Plasticizer" by Eastman Chemicals.
In formulating the compositions of the present invention, any suitable solvent
or volatile carrier may be employed. However, it has been found that the
solvent/volatile carrier preferably comprises one or more selected from the
group
consisting of alcohols (such as ethanol), ketones (such as acetone), ethers
(such as
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chloroform), aromatic hydrocarbons (such as toluene), esters (such as ethyl
acetate),
and water.
In selecting or formulating a combination of ingredients for the
solvent/volatile carrier, it has been found that the preferred compound or
compounds should act as a solvent for the carrier and at an evaporation rate
which is
slow enough to allow a complete application of the active ingredients to nail
or skin
surfaces, as well as being fast enough to prevent rub-off of the composition
in the
event the nail or skin surface comes into contact with another surface.
One preferred formulation for the therapeutic film forming composition is
detailed in Table II. In forming this preferred composition, the film former
namely
Eudragit RL-100, is first dissolved in the acetone/ethanol/water carrier.
After a
clear solution is formed, the other ingredients are added and intermixed
therein until
completely dissolved. In addition, the desired therapeutic agents are also
added and
intermixed therewith to form the desired therapeutic film forming composition
for
application to the nails or skin.
TABLE II
INGREDIENT
QUANTITY
Clobetasol propionate 0.05 % w/v
Urea 3 % w/v
Dibutyl phthalate 1.5 % w/v
Eudragit RL-100 7 % w/v
Ethanol 70 % w/v
Water q.s. to 100%
In completing the therapeutic film forming composition of this invention, one
or more therapeutic substances are incorporated into the compositions in
sufficient
quantity to provide the effect desired. In general, the therapeutic substance
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employed comprises one or more selected from the group consisting of
coTticosteroids, chemotherapeutic agents, anesthetics, antihistamines, anti-
bacterials, anti-parasitics, anti-viral agents, anti-oxidants, tar,
anthralines,
immunomodulators, keratolytics, and anti-neoplastics. Although a wide variety
of
chemical products come within the scope of these medications, the following
list
provides typical compositions that are effectively employed as a part of the
treatment system of the present invention. However, this listing is provided
for
exemplary purposes only, and is not intended to limit the present invention
thereto.
In this regard, corticosteroids may comprise one or more selected from the
group consisting of hydrocortisone, triamcinolone, betamethasone, and any
other
steroids commonly used in topical applications to the skin; chemothera-peutic
agents
may comprise one or more selected from the group consisting of SFU, Bleomycin,
methotrexate, cytotoxic agents; anesthetics may comprise one or more selected
from
the group consisting of lidocaine, prilocaine, and pramoxine, antihistamines
may
comprise one or more selected from the group consisting of diphenhydramine and
its
salts; or doxepin, anti-bacterials may comprise one or more selected from the
group
consisting of gentamicin, tetracycline, erythromycin, and clindamycin;
anoxicillin,
anti-parasitics may comprise one or more selected from the group consisting of
metronidazole, permethrin, and crotamiton; anti-virals may comprise one or
more
selected from the group consisting of acyclovir; antioxidants may comprise one
or
more selected from the group consisting of ascorbic acid and tocopherol;
immunomodulators may comprise one or more selected from the group consisting
of
imiquimod and beta glucan; keratolytics may comprise one or more selected from
the group consisting of salicylic acid; and anti-neoplastics may comprise one
or
more selected from the group consisting of cytotoxic agents and
immunomodulators.
Furthermore, as detailed herein, it has also been discovered that the use of a
heat gradient, as provided by one of the alternate embodiments of the present
invention, is effective in causing enhancing agents to be more efficiently
employed.
In this regard, as is fully detailed below, enhancing agents which
particularly benefit
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from the use of this embodiment of the present invention comprise one or more
selected from the group consisting of solvents, surfactants, ethers, esters,
fatty acid
glycerides, urea, oleates, liposomes, retinoids, and occlusive compounds.
As discussed above, the present invention comprises the use of a therapeutic
film forming composition independently in one embodiment, and also comprises
the
use of a heat delivery member which is employed in combination with the
therapeutic film forming composition. In the use of the present invention on a
nail
and/or skin surfaces, the therapeutic film forming composition is applied to
the nail
and/or skin surface. Once the film layer is established, the heat delivery
member,
when employing this embodiment, is placed over the nail to provide a
continuous
heat gradient directly to the affected nail and/or skin surface.
As stated above, the application of heat has been found to enhance the
delivery and efficacy of many therapeutic substances. When employing this
embodiment, heat delivery is preferably achieved by employing a heat delivery
pad
used in combination with a holding member. In the preferred construction, an
exothermic pad or heat delivery patch is employed for the heat source.
Exothermic
pads or heat delivery patches have been previously developed and typically
comprise
a porous film or pad of woven or non-woven material incorporating chemicals
which will react exothermically to generate heat in the presence of oxygen.
Although any desired chemicals can be employed, exothermic pads or heat
delivery
patches typically contain moxa or a mixture of iron powder, activated
charcoal,
wood fibers, water and salt. Alternatively, a mixture of alkaline sulfides and
iron
carbide are employed with the chemicals stored in an inert, oxygen-free,
chamber to
prevent exposure to oxygen prior to use. In addition, the pores of the pad are
of
sufficient size to assure that the required air flow is achieved. If desired,
any
alternate heat producing pad, product, or construction can be employed.
Prior to use, the patch/pad is typically sealed within a pouch which is
odorless or formed with an inert gas, such as nitrogen. As long as the
patch/pad
remains in the sealed container until use, no chemical reaction takes place.
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However, once the pouch is open, the presence of the oxygen in the air causes
the
chemicals to react and the desired exothermic reaction is produced.
In this embodiment of the present invention, the exothermic pad or heat
delivery patch is separately employed by having the user place the pad or
patch on
the desired site where heat treatment is being sought. If desired, the heat
delivery
patch or exothermic pad is separately secured to the desired site by adhesive
means
associated therewith.
Once the patch/pad is secured in the precisely desired location, the holding
member of the treatment system of the present invention is affixed to the
desired
location, peripherally surrounding and securely maintaining the heating pad or
exothermic patch in the desired location, assisting in regulating and
controlling the
heat level and air transmission to the exothermic pad or heat delivery patch.
In this
way, the desired, controlled heat delivery or heat gradient is realized,
enabling a
broad range of medical conditions to be effectively treated. In addition to
providing
controlled heat delivery for the direct treatment of certain medical
conditions, the
use of a heat gradient as provided by this embodiment of the fully integrated
treatment system of the present invention is effective, improving and
enhancing the
penetration of the systemic and topical medications incorporated in the
therapeutic
film forming composition.
As is evident from the foregoing, a wide variety of broadly diverse medical
conditions are effectively and efficiently treated using the treatment system
of the
present invention. As detailed above, one embodiment of the treatment system
of
the present invention incorporates a heat delivery patch or exothermic pad in
combination with a holding member which maintains the heat delivery patch or
exothermic pad in a precisely desired location where the particular medical
problem
is manifested or where heat delivery or a heat gradient is desired. In
addition, nail
or skin penetration enhancing agents may be integrated into the treatment
system of
this invention for further enhancement of its efficacy.
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One area in which the use of heat has been widely documented is in the
treatment of warts. In this regard, heat treatment for warts is fully
disclosed in
Dvoretzky. U.5. Patent 5,053,024. However, the use of heat in treating other
skin
disorders or medical conditions as well as the use of heat for assisting in
the
transmission and/or absorption of medicines and nail/skin penetration
enhancing
agents is generally unknown and represents an advance in this technological
area,
particularly in combination with a therapeutic film forming composition.
By employing this embodiment of the treatment system of the present
invention, which comprises a therapeutic film forming composition in
combination
with a holding member and a heat delivery patch or exothermic pad, the
temperature
of the nail or skin is elevated and maintained between about 39° to
45°C., for
periods of time ranging between about 1 and 10 hours. In addition, by
employing
the present invention, the heat level to which the nail or skin is exposed is
maintained in a small, controlled range, which represents the optimum heat
exposure for treating the medical condition and delivering the precisely
desired
medicines. As a result, optimum performance and treatment is realized.
In accordance with the present invention, the support member is specifically
designed for being quickly and easily mountable to a part of the body, such as
a
finger, in peripheral, surrounding engagement with the nail being treated, and
remain in the precisely desired location in cooperating association with the
film
forming composition and the heat delivery patch or exothermic pad.
Furthermore,
the support member of the present invention is also specifically constructed
from
material particularly designed for cooperating with a heat delivery patch or
exothermic pad to synergistically interact therewith for assuring that the
precisely
required temperature levels are maintained and optimum oxygen flow is realized
for
the precisely desired period of time.
The support member forming a component of the holding system of the
present invention may be constructed in a variety of alternate configurations
for
providing the desired, quicky, easy, secure mounting thereof directly to any
forger
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or toe, or any other portion of the human anatomy where treatment is likely to
be
needed. In this regard, one embodiment of the holding system of the present
invention comprises a continuous, substantially cylindrically shaped tube
member.
By employing a cylindrically shaped member, the holding system of the present
invention is able to be easily mounted onto the hands or feet of the user,
peripherally surrounding the nail to be treated, securely maintaining and
cooperating
with the pre-mounted exothermic pad or heat delivery patch in the precisely
desired
location.
One feature of the present invention is the material employed for forming the
treatment system of this invention. In this regard, most woven or non-woven
materials are capable of being employed for forming the holding member.
However, it has been found that the preferred material comprises an elastomer
in its
entirety or formed therein, in order to provide flexibility in easily mounting
and
securing the holding system in place. In one preferred construction, the
elastomer is
integrally formed as a part of the material, such as a thermoplastic
elastomer. In
this regard, the preferred thermoplastic material comprises a foamed
thermoplastic
elastomer selected from the group consisting of polyurethane, polyolefins,
polybutylenes, polyethylenes, polyesters, ethylene-propylene rubbers,
polypropylenes, silicones, and vinyl based resins.
By employing a foamed thermoplastic elastomer, a precisely desired
combination of closed cells and open cells is obtained, with the ratio of
closed cells
to open cells being controlled within a preferred range. In this way, the heat
retention and/or insulation capabilities of the material are precisely
controlled as
well as the ability of the material to transmit oxygen from the surrounding,
ambient
air directly to the location of the heat delivery patch or exothermic pad.
In accordance with the embodiment of present invention wherein heat
delivery is employed, the temperature delivered directly to the nail or skin
surface
by the exothermic pad or heat delivery patch is precisely controlled in a
narrow
range, for a predetermined length of time, due to the insulation provided by
the
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holding system. In addition, oxygen is circulated continuously through the
holding
system to provide proper operation of the exothermic pad/patch as well as
provide
air circulation to the surface of the nail or skin being treated.
It will must be seen that the object set forth above, among those made
apparent from the preceding description, are efficiently obtained and, since
certain
changes may be made in carrying out the above process, in the described
product,
and in the constructions set forth without departing from the scope of the
invention,
it is intended that all matter contained in the above description shall be
interpreted as
illustrative and not in a limiting sense.
It is also to be understood that the following claims are intended to cover
all
of the generic and specific features of the invention herein described, and
all
statements of the scope of the invention which, as a matter of language, might
be
said to fall therebetween.
Particularly, it is to be understood that in said claims, ingredients or
compounds recited in the singular are intended to include compatible mixtures
of
such ingredients whenever the sense permits.
Having described our invention, what we claim as new and desired to secure
by Letters Patent is:
