Note: Descriptions are shown in the official language in which they were submitted.
1g~9~i3il
Background of the Invention
Air fresheners or space deodorants have come into
increasing use in the household market in recent years. Their
sales and use have increased rapidly and represent a substan-
tial market. Such products usually consist of liquid, aerosol,
or more generally, a semi-solid composition comprising various
oils and other components packaged in a container provided
with openings to expose the fragrance composition to the
atmosphere. The fragrance components volatilize into the
atmosphere -to mask or otherwise decrease the perception of
malodor that may be presen-t therein.
Almost invariably the freshener compositions are
comprised of volatile materials that lend a distinct fragrance
of their own to the atmospheric environment. While the
fragrances preferred by consumers change from time -to time
they usually fall into categories such as those of "floral
scents", "citrus scents", "pine scents", and "herbal scents"
and other less distinct groupings referred to as "fantasies".
All such scents impart their own distinct fragrance to the
atmosphere and all rely upon a number of theoretical mutually
operative mechanisms to lower the perceived strength of
malodor.
Since all such fragrances rely upon these effects,
they are only effective to the extent that they volatilize
efficiently to impart a significant amount of active material
to the atmosphere to combat malodors present in their vicinity.
While such compositions at the present state of the art, are
quite effective in producing a high or adequate level of
active volatile material in the atmosphere when new and
fresh, they usually rapidly lose their potency, or are so
volatile that the active materials are completely evaporated
within a short period of time, say within a few days when
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1~96311
continuously exposed to the ambient atmosphere.
It is therefore of interest to produce compositions
that retain their effectiveness over longer periods of time
whereby space deodorants may have an extended effective life
and the resultant economic benefit will be realized by the
consumer.
In the past, efforts to solve this problem have
resorted to compositions utilizing less volatile fragrances,
or formulations wherein the fragrances tend to be relatively
"immobilized". In the first instance, the less volatile
fragrances may be so non-volatile as to fail to produce an
effective level of fragrance or active material in the
ambient atmosphere. In the second instance, resort is
often made to solid or semi-solid gels or similar formulations
which reduce the volatility of the active components by
requiring that they migrate through the mass of the gel or
semi-solid toward its atmospheric interface prior to vola-
tilization, thereby increasing the active life of the composi-
tion. Such solid or semi-solid compositions, however, are
tedious to formulate; requiring mixing, heating, pouring into
moulds, or otherwise forming the gels and semi-solids, so that
the active components are effectively volatile without being
too tightly bound within the formulation such that their
activity is unduly depressed. In the case of aqueous alginate
and carrageenan based gels, the unsightly shrinkage over a
period of time of the semi-solids thus produced is, in
practice, impossible to avoid.
It will become obvious to one skilled in the art
that the above disadvantages are avoided by use of the present
invention.
Brief Description of the Invention
The present invention relates to air freshener
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;3~
formulations and more specifically to air freshener formula-
tions wherein the following benefits beyond those of the
current state of the art are realized:
1. Reduction of the rate of volatilization of
the active components of the odor counteractant composition.
2. Prevention of migration of the perfume oil,
caused by repeated vaporization and condensation in an
enclosed space to surfaces other than those to which the
oil was applied.
3. Stabilization of the aesthetic qualities of
the fragrance of the active composition by the reduction of
the rate of its degradation due to heating, aging and intrinsic
or extrinsic chemical reaction or instability.
4. Stabilization of the aesthetic quality by
"rounding" or "smoothing" of perfume oils, when said
stabilizers are judiciously applied by one skilled in the
perfumery art.
The above listed benefits are achieved by incor-
porating an effective quantity of an alkylphenol ether of
polyethylene glycol into the formulation. In particular,
alkyl phenoxy polyethoxy ethanols averaging from 9 to 12
moles ethylene oxide, and alkyl radicals ranging from 8 to 9
carbon atoms therein are especially effective in achieving
the above enumerated benefits.
The addition of such alkyl phenoxy polyethoxy
ethanols to "air freshener" quality formulations also
appears to improve the olfactory quality of the formulation
and to "round out" or to "smooth" the fragrance to make it
more pleasing to the person receiving the fragrance, providing
the fragrance composition is judiciously chosen, preferably
by one skilled in the art of perfumery. In some instances
the result of the addition of said "ethoxylates" can result
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- ~96311.
in an effect which might be termed "dulling" or as suppression
of "topnote" resulting in a "flatting" effect. Judgement must
be exercised in such a case, whether the benefits of 1, 2,
and 3, above, outweigh the possible undesirable effect in
4 above. The case more often, however, is one of enhancing
the aesthetic value of "air freshener" quality oil; making
it perceived as less "harsh" or less "chemical" smelling.
The addition of alkyl phenoxy polyethoxy ethanols
to the formulation also reduces the undesirable characteris-
tics of fragrance oil formula-tions to evaporate and recondense
in a closed space such as a package to form beads or droplets
of pure fragrance oil. The "evaporation - condensation"
phenomenon in the past has hindered the marketing of such
formulations in other than semi-solid form or in pressurized
containers and has prevented their being effectively marketed
by the simple absorption of said fragrance oils onto any
number of inexpensive absorbent substrates such as paper
pads, etc. Addition of the alkyl phenoxy polyethoxy ethanols
reduces this undesirable characteristic to the extent that
the liquid formulations may be absorbed on any suitable
porous material and be packaged in a closed container without
the evaporation and recondensation of the fragrance oil to
adjacent inner surfaces of the package.
It is therefore an object of this invention to
prepare air freshener formulations having a longer effective
life.
It is another object of the invention to extend
the useful life of fragrance oils.
It is another object of the invention to stabilize
fragrance oils against the effect of degradation due to
heating, aging, intrinsic or extrinsic chemical instability.
It is still another object of the invention to
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provide air freshener formulations that do not migrate in
the container thereof but tend to remain in the substrate
into which they were absorbed.
Other benefits and advantages of the invention will
become apparent from a review of the following specification
and claims as well as -the drawings wherein:
FIGS. 1, 2, 3 and 4 are all representations of the
loss in weight with time of four different fragrance oil
formulations, as compared with the same fragrance formulations
compounded with an added quantity of alkyl phenoxy polyethoxy
ethanols.
Detailed Description of the Invention
Air freshener formulations generally comprise as an
essential component, one or more fragrance oils; or in lieu
of these, what could be considered dS being more commonly
practiced in the present state of the art of "air freshener"
fragrance technology, man-made "synthetic" mixtures. These
"synthetics" approximate essential oils in their olfactory
impression and often consist of essential oil fractions, and
chemical odorants of which there is no counterpart found in
nature, and chemical odorants known to have odor counteractant
activity. The substances function in an air freshener device
by an evaporative action to distribute their fragrance and
active materials into the surrounding air spaces. These
essential oils are standard articles of commerce and are
derived from a great number of plant and animal sources, and
virtually all have their "synthetic" counterparts as a result
of advances in synthetic organic chemistry. Generally, many
fragrance oils or "synthetics" are compounded together to
produce the fragrance effects desired by the compounder.
The fragrance oils and synthetics, in turn, are
compounded with additional components that serve several
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96~11
functions; often the fragrance oils and "synthetics" themselves
serve in these functions. Among these functions are so called
"fixation" of the fragrance to increase its permanence, solu-
bilization of the oils, and volatilization control agents,
etc. In addition, in many instances, these components, are
combined with other materials such as alginates and carrageenans
in an aqueous medium to produce a semi-solid gel in the event
that the fragrances are to be packaged as non-liquid formula-
tions.
It has now been determined that the addition of a
quantity of alkyl phenoxy polyethoxy ethanol, to the fragrance
oil formulation, results in a stabilization of the fragrance
oils whereby the effective "life" therefore is considerably
~xtended. In this context, "life" is taken to mean the
extension of the fragrance oils ability to produce effective
levels of fragrance in the surrounding environment over a
period of time greater than is the-case in the absence of
these ethoxylates.
The presence of these materials results moreover in
additional advantages. Specifically, the recondensation of
the fragrance oils on nearby surfaces, i.e., the package, is
essentially eliminated whereby the formulation may be prepared
in a liquid form and absorbed on any porous material, such as
blotting paper and the like thereby to produce a "dry" product.
This effect could be thought of as a corollary to the extension
of the life of the composition due to its depression of over-
all vapor pressure and the high affinity that alkyl phenoxy
polyethoxy ethanols have for organic vapors in general. Either
or both of these effects are operative to prevent migration of
the fragrance oil from the absorbent substrate to other areas
where condensation of the oil is undesirable.
In the preferred formulations of the invention,
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~.~9~311.
fragrance oils, man-made "synthetic" mixtures, essential oil
"fractions" and "chemical odorants", and chemical odorants
known to have counteractant activity generally received, in
practice as, a "finished" composition are combined with alkyl
phenoxy polyethoxy ethanols to produce the desired air
freshener product. These materials may be in any standard
formulation or variation thereof; the formulation, in this
respect, is prepared to produce the desired fragrance or odor
counteractant activity in accordance with state of the art
of perfumery technology.
Any number of fragrances are useful in the air
freshener`formulation. Some examples are: Citronellol,
hydroxy-citronellol, rhodinl, eugenol, genanoil, rose oil,
heliptropine, peru balsam, ylang-ylang oil, isoeugenol,
bergamot, coumarin, musk, and all or any of the "synthetic"
counterparts of the foregoing, and odorant chemicals of
which there is no counterpart in nature. These materials
are generally used in combination to achieve the desired
fragrance and odor counteractant effect.
Components to enhance or vary fragrances are
multitudinous and are comprised of virtually all organic
functional groups including alcohols, esters, ketones,
aldehydes, acids, terpines, ethers and other materials of
a highly complex nature, to name a few. Some of the fore-
going materials function not only as odorants but to dual
purposes such as solvents, viscosity controlling agents,
etc.; while others used in trace amounts may serve as
fragrance modifiers. All of the above may be included in
the present state of the art of perfumery in the formulation
of an odor counteractant compound in accordance with the
desires of the formulator.
To this prepared, sometimes very complex composition
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of fragrances, enhancers and modifiers is added from about 5%
to 95% by weight of alkylphenol ethers of polyethylene glycol
stabilizer. In the preferred formulations the compounds of
the class octylphenyl ethers of polyethylene glycol are used.
Such compounds have the general formu]a:
C8H17 ~ (OCH2CH2)xOH. Those agents of the above
-
structure wherein X is from 9 to 12 are especially preferred
in the formulation.
The octylphenol ethers of polyethylene glycols are
commercially available (Rohm and Haas, under the Trade Mark
Tritons) as a mixture of polyoxy e-thylene chains of length
of 1 to 30 oxyethylene units. These are generally secured
as mixtures of varying polyoxyethylene chain lengths distri-
buted according to the Poisson distribution, and in practice,
chain length can be reasonably well specified and are articles
of commerce. Those agents having an average chain length
from 9 to 12 moles of ethyleneoxide are especially preferred
in the formulations of the invention.
The alkylphenol ethers of polyethylene glycol are
often used, due to their surface-active properties, to render
perfume oils soluble in, dispersed in, or otherwise integrated
into aqueous media.
Most generally, the "stabilized" fragrance formula-
tion is, in the context of this invention, absorbed in a
porous matrix, that is generally a type of blotting paper
which is then packaged in a sealed container for storage and
subsequent distribution for retail sales. In use, the
container is unsealed and opened to release the fragrance
into the surrounding environment.
It has been found that the addition of alkyl
phenoxy polyethoxy ethanol stabilizes the fragrance components
so as to appreciably extend their useful life, i.e., prolong
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the time during which the formulation xetains its ability to
effectively provide the desired level of fragrance in its
surroundings while being continuously or continually exposed
to the ambient atmosphere; protect the aesthetic qualities
of the fragrance of the active compound by reduction of the
rate of its degradation due -to heating, aging, and intrinsic
and extrinsic chemical reaction or instability; prevention
of migration of the perfume oil caused by repeated vaporiza-
tion and condensation to surfaces other than those to which
the oil was applied; and improvement of the aesthetic quality
or "smoothing" of the perfume oil when said invention is
judiciously applied by one skilled in the perfumery art.
One method of determining the "life" of the
fragrance oil formulation absorbed as described in the
foregoing, is to measure its weight as a function of time.
Such loss is due to evaporation of the various components
to the surrounding atmosphere. In order to test the
effectiveness of the formulations of the invention, four
fragrance oil test compounds were prepared. Eight grams
of each test fragrance oil formulation were absorbed into
a 4 millimeter thick blotter paper which had a total of 80
sq. inches evaporative surface area. Second, eight gram
samples each of the same 4 fragrance oil formulations were
then mixed with 8 grams each of octylphenol polyethoxy
ethanol (average 9-10 ethylene oxide groups) and the
individual samples were absorbed on said blotter paper
which was identical in size with those previously noted.
All blotter paper samples were then allowed to evaporate at
controlled and identical conditions into the surrounding
atmosphere and were reweighed periodically. The four test
compositions of the fragrance oil formulations were as
follows:
g
9631.1
Formula I
Parts by
weight
225 Amylcinnamic Aldehyde
670 Benzyl Benzoate
3400 Citronellol
450 Diethylphthalate
1460 Hydroxycitronellol
225 Indole 10% in Diethylphthalate
10 2420 Phenylethyl Alcohol
1150 Rhodinol
10000
Formula II
275 Aaldehyde C-8 10~ in Diethylphthalate
1850 Eugenol
600 Geraniol
470 Indole 10% in Diethylphthalate
730 Linalyl Acetate
2500 Methyl Anthranilate
20 3150 Petitgrain Oil
425 Phenylethyl Alcohol
10000
Formula III
324 Acropal (Firmenich*)
39 Bois de Rose Oil, Brazil
26 Heliotropine
114 Tincture Civet 3~ in Alcohol 39-C
229 Iralia, Pure (Firmenich*)
110 Peru Balsam, Decolorized, 10~ in Alcohol 39-C
30129 Violette AC (Ionine Alpha)
14 Ylang Oil II
Irophore (Firmenich*)
10000
Formula IV
225 Amyl Salicylate
91 Benzyl Salicylate
192 Coumarin
248 Isobutyl Salicylate
28 Isoeugenol, Extra
40 25 Musk Ambrette
28 Violette AC (Ionone Alpha)
28 Ylang Oil II
135 Bergamot 136 (Synthetic)
10000
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* Trade Mark
- 1~9631~L
FIGS. 1, 2, 3 and 4 of the drawing present, respec-
tively, plots of the natural logarithins (loge) of the sample
weights as against time (days), for each of the sample
formulations 1, 2, 3 and 4. In each figure the curves
indicated by the O's present data for the fragrance oil-
octylphenoxy polyethoxy ethanol formulations; while the
curves indicated by the X's present data for the fragrance
oil formulations alone.
A review of each of the FIGS. will clearly indicate
that the invention formulations suffered considerably less
weight loss over time as compared to the fragrance oil
formulations alone.
In a second experiment to detect "migration", the
blotters were placed in "cage-like" containers open to the
ambient air. These containers had a covering "jacket" which
could be completely or partially removed to permit access to
the ambient air. But in this experiment the jackets were
sealed and then subjected to temperature fluctuations which
might be typical of those encountered in the course of
distribution and sale of such a device. The temperature
- variations were on the order of 50 (50F - 100F). Many
experiments of this nature were carried out not only with
the above test compounds but with a large number of typical
"air freshener" compounds. At the end of varying amounts of
time (from 1 week to 9 months) the containers were opened
and checked for migration or recondensation of the formulation
on the inner surfaces of the container. No such migration
or recondensation was noted in the case of these compositions
which contained octylphenoxy polyethoxy ethanol. Thus, it
appears that the addition of this material and its analogs
to fragrance oil formulations modifies their vaporization-
condensation properties by either lowering the total vapor
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pressure of the fragrance oil mixture and/or by modifying their
recondensation behavior. This may be explained by the
stabilizer's high affinity for organic vapors, which prevents
the recondensation of the fragrance oil on surrounding
container surfaces.
In addition, the above test formulations and a large
number of typical "air freshener" formulations were sealed
in the above described devices and were subjected to tempera-
tures which normally destroy much of the aesthetic quality
of such fragrance oils. It was found with the above test
mixtures and most commercial "air freshener" fragrance
compounds that one week of a temperature of 140F was
sufficient, by sensory panel evaluation, to seriously impair
the olfactory quality of the oils. On the other hand, when
the same oils and test compounds were mixed in a ratio of l:l
with octyphenol polyethoxy ethanol, there was generally
reported by test panel members a dramatic reduction in the
- amount of degradation due to the heat encountered by the
oils. The upper temperature limit in normal shipping
practices of commercial articles is commonly considered to
be 140F; but even brief periods at this temperature in
devices such as these in which there is a high ratio of air
to oil would result in the degradation of the perfume oil
and an attendant decrease in ove~all aesthetic value.
Similar experiments as the above were carried out
at a constant temperature (100F) with aging as a single
variable. Over a period of nine months to a year at 100F
olfactory panels found distinct, and in some cases dramatic,
differences between fragrance compositions "protected" by
the ethoxylates of this invention compared to those to which
no such protection was afforded. These effects have been
observed in a very large number of "air freshener" compounds
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and in great detail in the test compounds named above. Theabove test compounds were found to be easily degraded by
heating and aging in the absence of the ethoxylates
additives.
The mechanisms as to why ethoxylates of this series
can produce what is essentially a chemical stabilization of
the aesthetic qualities of the fragrance of the compositions
through the reduction of the rate of degradation by heating
and aging, and intrinsic chemical instability may be explained
by the following hypothesis. The individual ingredients
which comprised the fragrance formulation are sequestered
by the alkyl phenoxy ethanol chain so as to separate the
ingredients one from another, to thus prevent the interaction
one with another, and to so bind them along the ethoxylate
molecule such that they are resistant to the oxidative effects
of the atmosphere contained within the device. This apparent
"chemical" stabilizing of what appears to be fragrance oils
in general was a completely unexpected and even startling
outgrowth of experiments designed to prolong the effective
life of air freshener devices.
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