BACKGROUND OF THE INVENTION
Field of the Invention
[0001] This invention is directed to alkyl cyanoacrylate compositions which are specifically
formulated for topical application onto intact or broken human skin. The compositions
of this invention are further formulated for single or repeated/intermittent use and
are resistant to premature polymerization.
State of the Art
[0002] Cyanoacrylates are well known in the art and can be represented by formula I:

wherein R is an alkyl or other suitable substituent. Such cyanoacrylates are disclosed
in U.S. Patent Nos. 3,527,224; 3,591,676; 3,667,472; 3,995,641; 4,035,334; and 4,650,826.
Typically, when applied onto living tissue, the R substituent is alkyl of from 2 to
10 carbon atoms and most often is butyl (e.g., n-butyl).
[0003] Suggested uses for alkyl cyanoacrylate compositions include their use in topical
application onto intact skin in order to form a polymer layer which inhibits blister
and pressure ulcer formation as described in U.S. Patent No. 5,306,490 and U.S. Patent
Application Serial No. 08/082,927. Still other suggested uses includes inhibiting
irritation arising from prosthetic devices as described in U.S. Patent No. 5,653,769
as well as inhibiting skin irritation and infection due to incontinence as described
in concurrently filed U.S. Patent No. 5,580565 entitled "USE OF CYANOACRYLATE ADHESIVES
FOR PROVIDING A PROTECTIVE BARRIER FILM FOR THE SKIN", Attorney Docket No. 026446-037.
When so employed, the cyanoacrylate adhesive composition is applied topically onto
intact skin and, after curing, a cyanoacrylate polymer coating is formed which coating
adheres strongly to the skin.
[0004] Other uses of alkyl cyanoacrylates include their use with small wounds as described
in U.S. Patent Application Serial No. 08/231,638 where the cyanoacrylate composition
is applied onto the surface of a topical wound (one which does not penetrate the dermal
layer) where, after curing, a protective coating or layer is formed over the wound.
[0005] Ideally, for topical applications as recited above, the alkyl cyanoacrylate compositions
should meet as many of the following criteria as possible:
(1) the alkyl cyanoacrylate composition should be formulated to be stable against
premature polymerization. Such formulations would therefore be suitable for storage
in applicators for multiple use applications and in spray applicators where unintended
polymerization can clog the spray mechanism;
(2) the alkyl cyanoacrylate composition should be of suitable viscosity for desired
application onto the skin;
(3) once applied to the skin, the alkyl cyanoacrylate should not polymerize so quickly
as to generate sufficient heat as to impart a "burning" sensation to the patient but
should cure within from about 10 seconds to about 1 minute after application;
(4) the resulting cured polymer should possess sufficient flexibility such that the
integrity of the polymer coating is not compromised by, for example, cracking;
(5) the resulting cured polymer should possess sufficient durability such that the
polymer does not prematurely shed from the patient's skin; and
(6) is non-toxic when applied to skin.
[0006] In contrast to topical applications, it is also known that alkyl cyanoacrylate compositions
can be employed in surgical environments as suture replacements or hemostats. When
employed in these environments, the parameters of the alkyl cyanoacrylate composition
for such applications often diverge from the compositional parameters for topical
application. For example, unlike topical application over large areas of skin, surgical
application of the alkyl cyanoacrylate composition is typically over very specific,
small total surface area internal parts of the human body and, accordingly, parameters
such as viscosity, curing time, flexibility, durability, etc., are often different
for this application as opposed to the parameters required for topical application.
Accordingly, while it is recognized in the Robertson, et al., U.S. Patent No. 3,722,599
to combine a polymerization inhibitor, a thickener, and a plasticizer with a fluoroalkyl
cyanoacrylate, these compositions are disclosed for use as suture replacements or
as hemostats and such compositions are not always suitable for topical application
onto the skin surface.
SUMMARY OF THE INVENTION
[0007] This invention is directed to novel alkyl cyanoacrylate compositions suitable for
topical application to human skin. The compositions of this invention are characterized
by the use of both a specific polymerization inhibitor and amount of this inhibitor
which effectively inhibits both premature and too rapid polymerization of the cyanoacrylate
adhesive component of the composition and by the use of a critical amount of a specific
plasticizer so as to maintain the integrity of the polymer over the skin surface.
In a preferred embodiment, the composition further comprises a suitable amount of
a thickening agent to provide for a compositional viscosity suitable for certain applications
onto human skin.
[0008] Specifically, in a first composition aspect, this invention is directed to an alkyl
cyanoacrylate composition which comprises
(a) from 75 to 82 weight percent of an alkyl cyanoacrylate;
(b) from 50 to 500 parts per million of SO2 as a polymerization inhibitor based on the entire weight of the composition; and
(c) from 18 percent to 25 percent by weight of a biocompatible plasticizer which biocompatible
plasticizer is a dialkyl phthalate wherein each alkyl group is independently from
1 to 10 carbon atoms
wherein the alkyl cyanoacrylate, in monomeric form, is represented by formula
I:

where R is alkyl of 4 to 10 carbon atoms
with the proviso excluding for the Contracting states AT, BE, CH, LI, DK, ES, GR,
IE, LU, MC, NL, PT, SE a composition containing n-butyl cyanoacrylate, 20 weight percent
of dioctyl phthalate as said biocompatible plasticizer and 200 ppm of sulfur dioxide
each based on the total weight of the composition, and with the proviso excluding
for the Contracting states DE, GB, FR, IT a composition containing 20 weight percent
of dioctyl phthalate as said biocompatible plasticizer and 200 ppm of sulfur dioxide
each based on the total weight of the composition.
[0009] In a second composition aspect, this invention is directed to an alkyl cyanoacrylate
composition which comprises
(a) from 75 to 80 weight percent of n-butyl cyanoacrylate;
(b) about 200 parts per million of SO2 based on the entire weight of the composition as a polymerization inhibitor; and
(c) from 20 percent to 25 percent by weight of a dialkyl phthalate independently having
from 1 to 10 carbon atoms in each alkyl group
wherein the n-butyl cyanoacrylate, in monomeric form, is represented by formula
I:

with the proviso excluding a composition containing n-butyl cyanoacrylate, 20
weight percent of dioctyl phthalate as said biocompatible plasticizer and 200 ppm
of sulfur dioxide each based on the total weight of the composition.
[0010] A composition containing n-butyl cyanoacrylate, 20 weight percent of dioctyl phthalate
as said biocompatible plasticizer and 200 ppm of sulfur dioxide each based on the
total weight of the composition is disclosed in, for example, International Patent
Application Serial No. PCT/US95/02241. 54 (3) and (4) EPC document WO95/22998 discloses
such compositions containing and alkyl α-cyanoacrylate, 20 weight percent of dioctyl
phtalate and 200 ppm of sulfur dioxyde, wherein the alkyl group contains from 2 to
10, more preferably from 2 to 8 carbone atoms and even more preferably butyl, pentyl
or octyl, but not for topical applications.
[0011] In the compositions of this invention, an amount of a biocompatible plasticizer of
from 18 to 25 weight percent is essential to provide for a polymer coating (film formation)
having the requisite degree of flexibility for the resulting polymer coating such
that the coating does not crack upon movement of the skin area to which it was applied
while also maintaining suitable durability in the polymer coating and an adequate
curing time of from about 10 to 60 seconds. In a preferred embodiment, the biocompatible
plasticizer is employed from 20 to 25 weight percent based on the total weight of
the alkyl cyanoacrylate composition.
[0012] Likewise, it has been found that the use of from 50 to 500 ppm of SO
2, for example from about 150 to about 250 ppm SO
2, as the polymerization inhibitor is essential in providing for an alkyl cyanoacrylate
composition having a curing time which is neither too fast (i.e., less than about
10 seconds) so as to cause a "burning" sensation when applied to the skin nor too
slow (greater than 60 seconds) as to interfere with effective application. Additionally,
as opposed to other polymerization inhibitors such as methane sulfonic acid, sulfur
dioxide is biocompatible with topical application onto human skin and does not produce
discernible skin irritation when employed in the amounts recited herein.
[0013] In a preferred embodiment, the alkyl cyanoacrylate composition of this invention
further comprises a sufficient amount of a thickening agent to provide for a viscosity
of from about 2 to 50,000 centipoise at 20°C. The thickening agent employed is any
biocompatible material which increases the viscosity of the alkyl cyanoacrylate composition
and includes, by way of example, a partial polymer of the alkyl cyanoacrylate, polymethyl
methacrylate (PMMA) or other preformed polymers soluble in the alkyl cyanoacrylate,
a suspending agent such as fumed silica, and the like with PPMA being preferred.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0014] This invention relates to specific alkyl cyanoacrylate compositions that are particularly
well suited for topical application to human skin.
[0015] As used herein, the following terms have the following meanings:
[0016] The term "cyanoacrylate" refers to an adhesive compound or mixture of compounds based
on cyanoacrylate monomers of formula I:

where R is selected from the group consisting of alkyl of 4 to 10 carbon atoms.
Partial polymers (i.e., oligomers) of such cyanoacrylates are also encompassed within
this definition.
[0017] Preferred R alkyl group are from 4 to 8 carbon atoms and include, by way of example,
n-butyl, iso-butyl, sec-butyl, n-pentyl, iso-pentyl, n-hexyl, iso-hexyl, 2-ethylhexyl,
n-heptyl, and octyl. More preferably, R is butyl or octyl and most preferably, R is
n-butyl.
[0018] These cyanoacrylates are known in the art and are described in, for example, U.S.
Patent Nos. 3,527,224; 3,591,676; 3,667,472; 3,995,641; 4,035,334; and 4,650,826.
[0019] Preferred cyanoacrylates for use in this invention are n-butyl-2-cyanoacrylate and
octyl-2-cyanoacrylate.
[0020] The "biocompatible plasticizers" used in this invention are dialkyl phthalates independently
having from 1 to 10 carbon atoms in each alkyl group. They are soluble or dispersible
in alkyl cyanoacrylate, which increases the flexibility of the resulting polymer coating
on the skin surface, and which is compatible with the skin as measured by the lack
of skin irritation. Suitable plasticizers are well known in the art. The stabilizers
include dibutyl phthalate, diethyl phthalate, dimethyl phthalate and dioctylphthalate.
The particular plasticizer employed does not produce skin irritation as measured by
well known assays such as primary skin-irritation (rabbit) as described in Example
3. A particularly preferred plasticizer is dioctylphthalate.
Compositions
[0021] As noted above, the compositions of this invention comprise from 75 to 82 weight
percent of an alkyl cyanoacrylate having 4 to 10 carbon atoms in the alkyl group,
from 50 to 500 parts per million of SO
2 as a polymerization inhibitor, and from 18 percent to 25 percent by weight of a biocompatible
plasticizer. The compositions are prepared generally by bubbling in the SO
2 and mixing the requisite amounts of the liquid plasticizer until a homogeneous mixture
is obtained. The mixing procedures are conventional and is typically conducted at
room temperature under anhydrous conditions to ensure against water contamination
of the composition. At the amounts employed, sulfur dioxide and the biocompatible
plasticizer are soluble in the alkyl cyanoacrylate and, accordingly, after mixing
a uniform solution is produced which solution can be optionally filtered to remove
insolubles.
[0022] The resulting composition can optionally contain a sufficient amount of a thickening
agent to provide for a viscosity of from about 2 to 50,000 centipoise at 20°C. The
thickening agent employed is any biocompatible material which increases the viscosity
of the alkyl cyanoacrylate composition and includes, by way of example, a partial
polymer of the alkyl cyanoacrylate, polymethyl methacrylate (PMMA) or other preformed
polymers soluble in the alkyl cyanoacrylate, a suspending agent such as fumed silica
and the like with PMMA being preferred. Thickening agents are deemed to be biocompatible
if they are both soluble in the alkyl cyanoacrylate composition and are compatible
with the skin as measured by the lack of skin irritation. As before, the lack of skin
irritation can be measured by conventional procedures such as primary skin irritation
(Rabbit).
[0023] The specific viscosity employed for the alkyl cyanoacrylate composition depends,
in part, on the intended application of the composition. For example, relatively low
viscosities are often preferred where application is to be made to a large surface
area. This preference results from the fact that those forms are less viscous and,
accordingly, will permit more facile large surface area application of a thin application.
Contrarily, where application is to be made to a specific position on the skin, higher
viscosity materials are preferred to prevent "running" of the material to unintended
locations.
[0024] The particular thickening agent employed to enhance the viscosity of the composition
is not critical. Preferred thickening agents include polymethyl methacrylate (PMMA),
partially polymerized cyanoacrylate adhesives as disclosed in U.S. Patent Nos. 3,654,239
and 4,038,345. Another preferred thickening agents for alkyl cyanoacrylate compositions
having a viscosity of from about 1500 to 50,000 is fumed silica and the use of this
material produces a gel for topical application.
[0025] For purposes of this invention, monomeric or partially polymerized n-butyl-2-cyanoacrylate
and/or iso-butyl-2-cyanoacrylate are particularly preferred cyanoacrylate and are
capable of effectively bonding to human skin tissue without causing histoxicity or
cytotoxicity.
[0026] Upon contact with skin moisture and tissue protein, the alkyl cyanoacrylate will
polymerize or, in the case of partially polymerized alkyl cyanoacrylate, will further
polymerize, at ambient conditions (skin temperature) over about 10 seconds to 60 seconds
to provide a solid layer which forms over and strongly adheres to the surface of the
skin.
[0027] The compositions may additionally contain one or more optional additives such as
colorants, perfumes, anti-diffusion agents, rubber extenders, modifying agents. In
practice, each of these optional additives should be both miscible and compatible
with the cyanoacrylate adhesive. Compatible additives are those that do not prevent
the use of the cyanoacrylate adhesives in the manner described herein.
[0028] In general, colorants are added so that the polymerized film will contain a discrete
and discernable color. Perfumes are added to provide a pleasant smell to the formulation.
Rubber extenders are added to further enhance the flexibility of the resulting polymer
coating. The amount of each of these optional additives employed in the cyanoacrylate
adhesive composition is an amount necessary to achieve the desired effect.
[0029] The resulting composition is generally stored in an applicator for use in a single
dose application or for use in repeated applications. Single dose applicators include
those having breakable or removable seals that prevent moisture, including atmospheric
moisture, from contacting the formulation and causing
in situ polymerization.
[0030] For repeated and intermittent usage, minimal exposure to atmospheric moisture is
required. This can be achieved by devices having very narrow outlets and low initial
dead space. One applicator for such repeated intermittent use is described in U.S.
Patent No. 4,958,748.
[0031] Another applicator comprises a conventional spray applicator wherein the cyanoacrylate
composition is sprayed onto the surface skin area. The spray rate of the applicator
can be controlled so that application of a metered quantity of this composition per
unit area of skin surface over a set period of time is controlled.
[0032] Still another applicator comprises a brush or solid paddle applicator wherein the
alkyl cyanoacrylate composition is "painted" onto the surface skin area containing
the superficial wound.
[0033] A preferred applicator for repeated and intermittent usage is an applicator suitable
for the non-sterile storage and metered dispersement of a alkyl cyanoacrylate composition
after opening of the applicator wherein the applicator is characterized as having
a resealable opening of no more than about 0.0516 square centimeters (0.008 square
inches) so as to permit the metered dispersement of the composition from the applicator
and which is capable of multiple administrations of the composition and is further
characterized as having resealing means such as a cap which either tightly mates with
the applicator or which screws onto the applicator.
[0034] Preferably, the opening of the applicator is about 0.0103 to about 0.0194 square
centimeters about (0.0016 to about 0.003 square inches).
[0035] In another preferred embodiment, the walls of the applicator are made of a pliable
material, so that upon application of pressure onto the walls, the walls depress sufficiently
to force the composition contained in the applicator through the opening. Preferably,
the applicator is manufactured with its opening covered by a metal foil or other similar
construction which closes this opening until the device is ready for use. The opening
is then reinstated by use of a pin or similar device which punctures the covering.
[0036] In applicators suitable for repeated intermittent uses, the alkyl cyanoacrylate composition
is stored at ambient conditions and is selected to be bacteriostatic. See, for example,
Rabinowitz et al., U.S. Patent No. 3,527,224. When the selected composition is bacteriostatic,
prolonged storage at ambient conditions is without regard to the sterility of the
formulation because there is no adverse buildup of bacteria during storage.
[0037] After application, the resulting coating will adhere to the skin for a period of
more than 24 hours, and preferably for at least about 2-4 days after which time it
sloughs off. Additional applications can be made if desired.
[0038] The coating protects the underlying skin because the adhesive forms a polymer coating
which extends over the entire surface of the skin. Because the coating is waterproof,
the patient is not prevented from bathing and other activities involving exposure
to water during the period the adhesive layer covers the skin.
Utility
[0039] The compositions of this invention are useful in inhibiting the formation of blisters
and the formation of pressure ulcers as described in U.S. Patent No. 5,306,490 and
U.S. Patent Application Serial No. 08/082,927. Additionally, the compositions are
also useful in inhibiting irritation arising from prosthetic devices as described
in U.S. Patent No. 5,653,769 the disclosures of such patent and patent applications
being incorporated herein by reference in its entirety. When so employed, the alkyl
cyanoacrylate composition described herein is applied topically onto intact skin and,
after curing, a cyanoacrylate polymer coating is formed which coating adheres strongly
to the skin. In each case, the resulting coating inhibits formation of blisters, pressure
ulcers and irritation arising from the prosthetic device.
[0040] Additionally, the alkyl cyanoacrylate compositions described herein can be employed
to form a protective coating over small wounds as described in U.S. Patent Application
Serial No. 08/231,638. When so used, the alkyl cyanoacrylate composition is applied
onto the surface of a topical wound and, after curing, a protective coating or layer
is formed over the wound.
EXAMPLES
Example 1
[0041] The purpose of this example is to evaluate the effect of the amount of plasticizer
in the alkyl cyanoacrylate composition on the properties of the resulting polymer
coating. In this regard, seven alkyl cyanoacrylate compositions were prepared. The
formulations comprised n-butyl α-cyanoacrylate in monomeric form, dioctyl phthalate
(DOP) as a representative plasticizer ranging from 15% to 50% by weight and 200 ppm
SO
2. The formulations were packaged in individual bottles.
[0042] One drop from each bottle was applied to the skin of a hand. The appearance, curing
time, film formation, flexibility and durability of each coating formed were evaluated
and the results are shown in Table 1.
[0043] In this example, curing times of greater than 1 minute were deemed unacceptable because
such curing times would interfere with effective application of the composition onto
human skin. Likewise, compositions which failed to polymerize and thereby form a coating
on the skin were rated as unsatisfactory. The durability criteria refers to the ability
of the composition to be retained on the skin for at least 24 hours and coatings which
failed to meet this criteria were deemed unsatisfactory. Lastly, the flexibility criteria
refers to the ability of the polymer coating to be retained on the skin without cracking
for a period of at least 24 hours and coatings which failed to meet this criteria
were also deemed to be unsatisfactory.
[0044] The example in table 1, where used is made of 20 weight percent of dioctyl phtalate,
is outside of the scope of the claims.
Table 1
| % DOP |
15 |
20 |
25 |
30 |
35 |
40 |
50 |
| Appearance |
+ |
+ |
+ |
+ |
+ |
+ |
+ |
| Curing Time (1 min.) |
+ |
+ |
+ |
+/- |
- |
- |
- |
| Film Formation |
+ |
+ |
+ |
+/- |
- |
- |
- |
| Flexibility |
- |
+ |
+ |
+ |
+ |
+ |
+ |
| Durability |
- |
+ |
+ |
+/- |
- |
- |
- |
[0045] A "+" indicates satisfactory; a "-" indicates unsatisfactory. All of these seven
samples appeared clear, water- white and dispensed cleanly in a dropwise fashion.
At dioctylphthalate levels of 35 weight percent or more, the n-butyl cyanoacrylate
was overwhelmed by the plasticizer and did not form an integral, physical film. Instead,
an oily residue resulted. At dioctylphthalate levels of 15 weight percent or less,
flexibility and durability suffered. The only coatings providing acceptable results
were those employing 20% and 25% plasticizer.
[0046] In addition, samples of n-butyl α-cyanoacrylate compositions containing 0% and 10%
DOP plasticizer were evaluated and found to form rigid, glass-like coatings, which
were uncomfortable, cracked and peeled from the skin.
Example 2
[0047] N-butyl cyanoacrylate compositions were prepared which compositions used either 100
ppm methane sulfonic acid or 200 ppm sulfur dioxide as the polymerization inhibitor.
Application of these compositions onto human skin indicated that compositions comprising
the methane sulfonic acid caused reddening and irritation of the skin within 6 hours
whereas the compositions comprising sulfur dioxide did not.
Example 3
[0048] The following assays demonstrate that the cyanoacrylate adhesive compositions tested
are safe when applied topically.
A. Cytotoxicity testing by the USP Elution Method
[0049] With the use of cell culture techniques, this test determines the lysis (cell death),
the inhibition of cell growth, and other toxic effects on cells caused by test materials
and/or extracts from the material. For this test, barrier film formed from an alkyl
cyanoacrylate composition of Example 1 (20% DOP) was extracted for 72 hours at 50°C
in normal saline. Mouse fibroblast cells were exposed to this extract for 48 hours
at 37°C. No reactivity of any kind (a "0" score) was observed.
B. Acute Systemic Toxicity -- Current USP
[0050] This test estimates the harmful effects of intimate exposure to test materials or
extracts in an animal model. Here, the barrier film formed from an alkyl cyanoacrylate
composition of Example 1 (20% DOP) was extracted in normal saline and cotton seed
oil for 72 hours at 50°C. Five young albino mice were injected I.V. with the saline
extract and five mice I.P. with the cotton seed oil extract. The animals were examined
at 4, 24, 48, and 72 hours. No reactions, weight loss or deaths were found in any
of the test animals.
C. Primary Skin Irritation Test (FHSA) in the Rabbit
[0051] This test estimates the irritation potential of test materials using appropriate
site tissue, such as skin, in an animal model. Six drops of the alkyl cyanoacrylate
composition of Example 1 (20% DOP) were applied to the intact and abraded skin of
six healthy albino rabbits and left in place for 24 hours. Test sites were graded
for erythema and edema at 24 and 72 hours. The skin irritation index was scored as
"0". There was no irritation observed on the skin of any of the rabbits.
D. Delayed Contact Sensization (Repeated Patch Method) in the Guinea Pig
[0052] This test estimates the potential for sensitization of a test material using an animal
model. Specifically, a film derived of the cyanoacrylate composition of Example 1
(20% DOP) was repeatedly applied to the intact and shaved skin of ten guinea pigs
over a three week period, for a total of nine applications. Prior to each product
reapplication, the film was removed from the animal by wiping with acetone. After
a recovery period of 14 days, the film was again applied to the same animals. Throughout
the study, all sites were observed for evidence of dermal reaction. Test results showed
a mild or faint skin reaction due to product removal with acetone. There was no evidence
of delayed dermal contact sensitization.
Claims for the following Contracting State(s): AT, BE, CH, LI, DK, ES, GR, IE, LU,
MC, NL, PT, SE
1. An alkyl cyanoacrylate composition which comprises
(a) from 75 to 82 weight percent of an alkyl cyanoacrylate;
(b) from 50 to 500 parts per million of SO2, based on the entire weight of the composition, as a polymerization inhibitor; and
(c) from 18 percent to 25 percent by weight of a biocompatible plasticizer which biocompatible
plasticizer is a dialkyl phthalate wherein each alkyl group is independently from
1 to 10 carbon atoms
wherein the alkyl cyanoacrylate, in monomeric form, is represented by formula
I:

where R is alkyl of 4 to 10 carbon atoms
with the proviso excluding a composition containing n-butyl cyanoacrylate, 20 weight
percent of dioctyl phthalate as said biocompatible plasticizer and 200 ppm of sulfur
dioxide each based on the total weight of the composition.
2. The alkyl cyanoacrylate composition according to Claim 1 which comprises from 150
to 250 ppm SO2.
3. The alkyl cyanoacrylate composition according to Claim 2 which comprises 200 ppm SO2.
4. The alkyl cyanoacrylate composition according to Claim 1 wherein R is alkyl of from
4 to 8 carbon atoms.
5. The alkyl cyanoacrylate composition according to Claim 3 wherein R is butyl or octyl.
6. The alkyl cyanoacrylate composition according to Claim 4 wherein R is n-butyl.
7. The alkyl cyanoacrylate composition according to Claim 1 wherein the dialkyl phthalate
is dioctyl phthalate.
8. An alkyl cyanoacrylate composition which comprises
(a) from 75 to 80 weight percent of n-butyl cyanoacrylate;
(b) 200 parts per million of SO2, based on the entire weight of the composition, as a polymerization inhibitor; and
(c) from 20 percent to 25 percent by weight of a dialkyl phthalate independently having
from 1 to 10 carbon atoms in each alkyl group
wherein the n-butyl cyanoacrylate, in monomeric form, is represented by formula
I:

with the proviso excluding a composition containing n-butyl cyanoacrylate, 20
weight percent of dioctyl phthalate as said biocompatible plasticizer and 200 ppm
of sulfur dioxide each based on the total weight of the composition.
9. The alkyl cyanoacrylate composition according to Claim 8 wherein said dialkyl phthalate
is dioctyl phthalate.
Patentansprüche für folgende(n) Vertragsstaat(en): AT, BE, CH, LI, DK, ES, GR, IE,
LU, MC, NL, PT, SE
1. Alkylcyanoacrylatzusammensetzung, umfassend
(a) 75 - 82 Gew.-% eines Alkylcyanoacrylats;
(b) 50 - 500 ppm (parts per million) SO2, bezogen auf das Gesamtgewicht der Zusammensetzung, als Polymerisationsinhibitor
und
(c) 18 - 25 Gew.-% eines biologisch kompatiblen Plastifizierungsmittels, das ein Dialkylphthalat
ist, worin jede Alkylgruppe voneinander unabhängig 1 - 10 Kohlenstoffatome aufweist,
wobei sich das Alkylcyanoacrylat in monomerer Form durch die Formel I:

mit R gleich Alkyl mit 4 - 10 Kohlenstoffatomen darstellen läßt,
mit dem Vorbehalt, dass eine Zusammensetzung, die n-Butylcyanoacrylat, 20 Gew.-% Dioctylphthalat
als das biologisch kompatible Plastifizierungsmittel und 200 ppm Schwefeldioxid, jeweils
bezogen auf das Gesamtgewicht der Zusammensetzung, enthält, ausgeschlossen ist.
2. Die Alkylcyanoacrylatzusammensetzung gemäß Anspruch 1, die 150 - 250 ppm SO2 umfasst.
3. Die Alkylcyanoacrylatzusammensetzung gemäß Anspruch 2, die 200 ppm SO2 umfasst.
4. Die Alkylcyanoacrylatzusammensetzung gemäß Anspruch 1, wobei R ein Alkyl mit 4 - 8
Kohlenstoffatomen ist.
5. Die Alkylcyanoacrylatzusammensetzung gemäß Anspruch 3, wobei R Butyl oder Octyl ist.
6. Die Alkylcyanoacrylatzusammensetzung gemäß Anspruch 4, wobei R n-Butyl ist.
7. Die Alkylcyanoacrylatzusammensetzung gemäß Anspruch 1, wobei das Dialkylphthalat Dioctylphthalat
ist.
8. Alkylcyanoacrylatzusammensetzung, umfassend
(a) 75 - 80 Gew.-% n-Butylcyanoacrylat;
(b) 200 ppm (parts per million) SO2, bezogen auf das Gesamtgewicht der Zusammensetzung, als Polymerisationsinhibitor
und
(c) 20 - 25 Gew.-% eines Dialkylphthalats, das in jeder Alkylgruppe unabhängig voneinander
1 - 10 Kohlenstoffatome besitzt,
wobei sich das n-Butylcyanoacrylat in monomerer Form durch die Formel I:

darstellen läßt,
mit dem Vorbehalt, dass eine Zusammensetzung, die n-Butylcyanoacrylat, 20 Gew.-% Dioctylphthalat
als das biologisch kompatible Plastifizierungsmittel und 200 ppm Schwefeldioxid, jeweils
bezogen auf das Gesamtgewicht der Zusammensetzung, enthält, ausgeschlossen ist.
9. Die Alkylcyanoacrylatzusammensetzung gemäß Anspruch 8, wobei das Dialkylphthalat Dioctylphthalat
ist.
Patentansprüche für folgende(n) Vertragsstaat(en): DE, FR, GB, IT
1. Alkylcyanoacrylatzusammensetzung, umfassend
(a) 75 - 82 Gew.-% eines Alkylcyanoacrylats;
(b) 50 - 500 ppm (parts per million) SO2, bezogen auf das Gesamtgewicht der Zusammensetzung, als Polymerisationsinhibitor
und
(c) 18 - 25 Gew.-% eines biologisch kompatiblen Plastifizierungsmittels, das ein Dialkylphthalat
ist, worin jeder Alkylgruppe unabhängig voneinander 1 - 10 Kohlenstoffatome aufweist,
wobei sich das Alkylcyanoacrylat in monomerer Form durch die Formel I:

mit R gleich Alkyl mit 4 - 10 Kohlenstoffatomen darstellen läßt,
mit dem Vorbehalt, dass eine Zusammensetzung, die 20 Gew.-% Dioctylphthalat als das
biologisch kompatible Plastifizierungsmittel und 200 ppm Schwefeldioxid, jeweils bezogen
auf das Gesamtgewicht der Zusammensetzung, enthält, ausgeschlossen ist.
2. Die Alkylcyanoacrylatzusammensetzung gemäß Anspruch 1, die 150 - 250 ppm SO2 umfasst.
3. Die Alkylcyanoacrylatzusammensetzung gemäß Anspruch 2, die 200 ppm SO2 umfasst.
4. Die Alkylcyanoacrylatzusammensetzung gemäß Anspruch 1, wobei R ein Alkyl mit 4 - 8
Kohlenstoffatomen ist.
5. Die Alkylcyanoacrylatzusammensetzung gemäß Anspruch 3, wobei R Butyl oder Octyl ist.
6. Die Alkylcyanoacrylatzusammensetzung gemäß Anspruch 4, wobei R n-Butyl ist.
7. Die Alkylcyanoacrylatzusammensetzung gemäß Anspruch 1, wobei das Dialkylphthalat Dioctylphthalat
ist.
8. Alkylcyanoacrylatzusammensetzung, umfassend
(a) 75 - 80 Gew.-% n-Butylcyanoacrylat;
(b) 200 ppm (parts per million) SO2, bezogen auf das Gesamtgewicht der Zusammensetzung, als Polymerisationsinhibitor
und
(c) 20 - 25 Gew.-% eines Dialkylphthalats, das in jeder Alkylgruppe unabhängig voneinander
1 - 10 Kohlenstoffatome besitzt,
wobei sich das n-Butylcyanoacrylat in monomerer Form durch die Formel I:

darstellen läßt,
mit dem Vorbehalt, dass eine Zusammensetzung, die n-Butylcyanoacrylat, 20 Gew.-% Dioctylphthalat
als das biologisch kompatible Plastifizierungsmittel und 200 ppm Schwefeldioxid, jeweils
bezogen auf das Gesamtgewicht der Zusammensetzung, enthält, ausgeschlossen ist.
9. Die Alkylcyanoacrylatzusammensetzung gemäß Anspruch 8, wobei das Dialkylphthalat Dioctylphthalat
ist.
Revendications pour l'(les) Etat(s) contractant(s) suivant(s): AT, BE, CH, LI, DK,
ES, GR, IE, LU, MC, NL, PT, SE
1. Composition de cyanoacrylate d'alkyle qui comprend
a) de 75 à 82 pour cent en poids d'un cyanoacrylate d'alkyle ;
b) de 50 à 500 parties par million de SO2, sur la base du poids total de la composition, en tant qu'inhibiteur de polymérisation
; et
c) de 18 pour cent à 25 pour cent en poids d'un plastifiant biocompatible lequel plastifiant
biocompatible est un phtalate de dialkyle dans lequel chaque groupe alkyle est indépendamment
de 1 à 10 atomes de carbone
dans laquelle le cyanoacrylate d'alkyle, sous forme monomérique, est représenté
par la formule I :

où R est un alkyle de 4 à 10 atomes de carbone
à la condition que la composition ne soit pas une composition contenant du cyanoacrylate
de n-butyle, 20 pour cent en poids de phtalate de dioctyle en tant que dit plastifiant
biocompatible et 200 ppm de dioxyde de soufre en se basant dans chaque cas sur le
poids total de la composition.
2. Composition de cyanoacrylate d'alkyle selon la revendication 1 qui comprend de 150
à 250 ppm de SO2.
3. Composition de cyanoacrylate d'alkyle selon la revendication 2 qui comprend 200 ppm
de SO2.
4. Composition de cyanoacrylate d'alkyle selon la revendication 1 dans laquelle R est
un alkyle de 4 à 8 atomes de carbone.
5. Composition de cyanoacrylate d'alkyle selon la revendication 3 dans laquelle R est
le butyle ou l'octyle.
6. Composition de cyanoacrylate d'alkyle selon la revendication 4 dans laquelle R est
le n-butyle.
7. Composition de cyanoacrylate d'alkyle selon la revendication 1 dans laquelle le phtalate
de dialkyle est le phtalate de dioctyle.
8. Composition de cyanoacrylate d'alkyle qui comprend
a) de 75 à 80 pour cent en poids de cyanoacrylate de n-butyle ;
b) 200 parties par million de SO2, sur la base du poids total de la composition, en tant qu'inhibiteur de polymérisation
; et
c) de 20 pour cent à 25 pour cent en poids d'un phtalate de dialkyle ayant indépendamment
de 1 à 10 atomes de carbone dans chaque groupe alkyle
dans laquelle le cyanoacrylate de n-butyle, sous forme monomérique, est représenté
par la formule I :

à la condition que la composition ne soit pas une composition contenant du cyanoacrylate
de n-butyle, 20 pour cent en poids de phtalate de dioctyle en tant que dit plastifiant
biocompatible et 200 ppm de dioxyde de soufre en se basant dans chaque cas sur le
poids total de la composition.
9. Composition de cyanoacrylate d'alkyle selon la revendication 8 dans laquelle ledit
phtalate de dialkyle est le phtalate de dioctyle.